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Studying the temporal variability of BL Lac objects at the highest energies provides unique insights into the extreme physical processes occurring in relativistic jets and in the vicinity of super-massive black holes. To this end, the long-term variability of the BL Lac object PKS 2155 304 is analyzed in the high (HE, 100MeV < E < 300 GeV) and very high energy (VHE, E > 200 GeV) gamma-ray domain. Over the course of similar to 9 yr of H. E. S. S. observations the VHE light curve in the quiescent state is consistent with a log-normal behavior. The VHE variability in this state is well described by flicker noise (power-spectral-density index beta(VHE) = 1 .10(+ 0 : 10) (0 : 13)) on timescales larger than one day. An analysis of similar to 5.5 yr of HE Fermi-LAT data gives consistent results (beta(HE) = 1 : 20(+ 0 : 21) (0 : 23), on timescales larger than 10 days) compatible with the VHE findings. The HE and VHE power spectral densities show a scale invariance across the probed time ranges. A direct linear correlation between the VHE and HE fluxes could neither be excluded nor firmly established. These long-term-variability properties are discussed and compared to the red noise behavior (beta similar to 2) seen on shorter timescales during VHE-flaring states. The difference in power spectral noise behavior at VHE energies during quiescent and flaring states provides evidence that these states are influenced by different physical processes, while the compatibility of the HE and VHE long-term results is suggestive of a common physical link as it might be introduced by an underlying jet-disk connection.
Measurement of the EBL spectral energy distribution using the VHE gamma-ray spectra of HESS blazars
(2017)
Very high-energy gamma rays (VHE, E greater than or similar to 100 GeV) propagating over cosmological distances can interact with the low-energy photons of the extragalactic background light (EBL) and produce electron-positron pairs. The transparency of the Universe to VHE gamma rays is then directly related to the spectral energy distribution (SED) of the EBL. The observation of features in the VHE energy spectra of extragalactic sources allows the EBL to be measured, which otherwise is very difficult. An EBL model-independent measurement of the EBL SED with the H.E.S.S. array of Cherenkov telescopes is presented. It was obtained by extracting the EBL absorption signal from the reanalysis of high-quality spectra of blazars. From H.E.S.S. data alone the EBL signature is detected at a significance of 9.5 sigma, and the intensity of the EBL obtained in different spectral bands is presented together with the associated gamma-ray horizon.
We search for high-energy gamma-ray emission from the binary neutron star merger GW170817 with the H.E.S.S. Imaging Air Cherenkov Telescopes. The observations presented here have been obtained starting only 5.3 hr after GW170817. The H.E.S.S. target selection identified regions of high probability to find a counterpart of the gravitational-wave event. The first of these regions contained the counterpart SSS17a that has been identified in the optical range several hours after our observations. We can therefore present the first data obtained by a ground-based pointing instrument on this object. A subsequent monitoring campaign with the H.E.S.S. telescopes extended over several days, covering timescales from 0.22 to 5.2 days and energy ranges between 270 GeV to 8.55 TeV. No significant gamma-ray emission has been found. The derived upper limits on the very-high-energy gamma-ray flux for the first time constrain non-thermal, high-energy emission following the merger of a confirmed binary neutron star system.
Discovery of Very-high-energy Emission from RGB J2243+203 and Derivation of Its Redshift Upper Limit
(2017)
Very-high-energy (VHE; > 100 GeV) gamma-ray emission from the blazar RGB J2243+203 was discovered with the VERITAS Cherenkov telescope array, during the period between 2014 December 21 and 24. The VERITAS energy spectrum from this source can be fitted by a power law with a photon index of 4.6 +/- 0.5, and a flux normalization at 0.15 TeV of (6.3 +/- 1.1) x 10(-10) cm(-2) s(-1) TeV-1. The integrated Fermi-LAT flux from 1 to 100 GeV during the VERITAS detection is (4.1 +/- 0.8) x 10(-8) cm(-2) s(-1), which is an order of magnitude larger than the four-year-averaged flux in the same energy range reported in the 3FGL catalog, (4.0 +/- 0.1 x 10(-9) cm(-2) s(-1)). The detection with VERITAS triggered observations in the X-ray band with the Swift-XRT. However, due to scheduling constraints Swift-XRT observations were performed 67 hr after the VERITAS detection, rather than simultaneously with the VERITAS observations. The observed X-ray energy spectrum between 2 and 10 keV can be fitted with a power law with a spectral index of 2.7 +/- 0.2, and the integrated photon flux in the same energy band is (3.6 +/- 0.6) x 10(-13) cm(-2) s(-1). EBL-model-dependent upper limits of the blazar redshift have been derived. Depending on the EBL model used, the upper limit varies in the range from z < 0.9 to z < 1.1.
B2 1215+30 is a BL-Lac-type blazar that was first detected at TeV energies by the MAGIC atmospheric Cherenkov telescopes and subsequently confirmed by the Very Energetic Radiation Imaging Telescope Array System (VERITAS) observatory with data collected between 2009 and 2012. In 2014 February 08, VERITAS detected a large-amplitude flare from B2. 1215+30 during routine monitoring observations of the blazar 1ES. 1218+304, located in the same field of view. The TeV flux reached 2.4 times the Crab Nebula flux with a variability timescale of <3.6 hr. Multiwavelength observations with Fermi-LAT, Swift, and the Tuorla Observatory revealed a correlated high GeV flux state and no significant optical counterpart to the flare, with a spectral energy distribution where the gamma-ray luminosity exceeds the synchrotron luminosity. When interpreted in the framework of a onezone leptonic model, the observed emission implies a high degree of beaming, with Doppler factor delta > 10, and an electron population with spectral index p < 2.3.
Die vorliegende Arbeit trägt den Titel: Intellektuellen-Rolle in Günter Grass Werken : „Die Plebejer proben den Aufstand“(1966), „Örtlich betäubt“(1969), „Aus dem Tagebuch einer Schnecke“(1972), und „Ein weites Feld“(1995).
Das erste Kapitel befasst sich insgesamt mit drei Haupttiteln
II. Der Intellektuelle
II.1 Das allgemeine Umfeld
In diesem Teil der Dissertation sollen Aussagen getroffen werden, die auf folgende und weitere Fragen eine Antwort geben: Was ist ein Intellektueller? Wie kam der Begriff zustande? Gibt es Unterschiede zwischen den Intellektuellen und wie werden sie eingeteilt?
II.2 Das deutsche Umfeld
Die Behandlung des Nazisystems und dessen historische Hintergründe vermittelt bedeutsame Lehren. Aber wozu braucht man diese Lehren? Gibt es Spuren von Nationalsozialismus heutzutage? Wo waren die Intellektuellen bei der Bildung des Nationalsozialismus? Ist der Nationalsozialismus erst mit Hitler aufgetaucht? Wenn zuvor, in welcher Phase hat er sich im Bewusstsein der Deutschen verankert? Ob theoretische bzw. geistige Tendenzen dazu beigetragen haben?
II.3 Das Bild von Grass als Intellektueller
II.3.1 Positionierung
Eine Hauptthese für Grass intellektuelle Positionierung wird durch die Verbindung zwischen Grass’ Grundkonzeption der gesellschaftspolitischen Intellektualität und der Gruppe 47 ermittelt. Dann bezweckt die Behandlung von Grass Bild nach Erscheinen seines autobiographischen Werks: „Beim Häuten der Zwiebel“ (2006), dass seine Intellektualität nicht nur aus dem positiven, sondern auch aus dem negativen Profil beleuchtet wird.
Aus der Darstellung zahlreicher Ansichten von Günter Grass werden fünf thematische Kernpunkte als Konzepte behandelt. Unter jedem Konzept sollen spezifische Vorschläge zur gesellschaftlichen Positionierung aufgezeigt werden.
II.3.2 Grass’ politische Merkmale
Es handelt sich hier um die intellektuellen Charaktereigenschaften. Dadurch kommen manche Fragen zu Wort: Hat Günter Grass gesellschaftliche Aktivitäten? Hat er die Voraussetzungen dafür? Wie ist der Umfang seiner Aktivitäten? Hat die Gruppe 47 Einfluss auf Grass intellektuelle Merkmale? Steht bei Grass eine Methode der gesellschaftspolitischen Arbeit zur Verfügung?
Dann wird die politische Sprache von Günter Grass und ihre Wirkung auf den Rezipienten untersucht. Danach wird nach Grass’ Auffassung von der Revision gefragt und ob sie mit seiner Auffassung der Aufklärung zusammenpasst. Darauf wird die Funktion der Revision in seinem literarischen Werk und in seiner gesellschaftspolitischen Aktivität gezeigt.
Abschließend werden die Argumente seiner Intellektualität untersucht:
Wie hat Grass’ gesellschaftspolitische Aktivität den konkreten politischen Rahmen berücksichtigt? Um diese Frage zu beantworten, muss der Zusammenhang zwischen Politik und Moral verdeutlicht werden.
III. Historischer Kontext und Inhalt der Werke
Unter diesem Titel wird erstens der historische Zusammenhang der untersuchten Werke skizziert. Dann werden meistens durch Argumente aus jedem Werk selbst nicht nur der Kern des Werkes und sein Handlungsverlauf, sondern auch die dafür angewandte Methode dargestellt.
IV. Bezug der untersuchten Werke zu konkreten gesellschaftspolitischen Fragen
IV.1 Interaktionswege des Intellektuellen mit der Gesellschaft, vor allem beim Wandel gesellschaftspolitischer Prozesse
Zentralkonzepte des ersten Werkes sind: Vermittlung, Engagement, Solidarität und die Aktualität als Maßstab. Diese werden durch zwei Konzepte des zweiten Werkes: Appell an Generationen beim Wechsel und Zusammenhaltsprinzip an Revision gebunden, sowie durch die Behandlung vom Prozess der Meinungsbildung im vierten Werk ausgearbeitet.
IV.2 Thematische Aspekte zur Vermeidung eines Naziregimes
Aus den thematischen Perspektiven der drei letzten Werke geht eine bunte Sammlung intellektueller Konzepte aus, die zur Bekämpfung von Nazivorsprünge verwendet werden können.
V. Pädagogische Strategien der untersuchten Werke
Die pädagogischen Aspekte der untersuchten Werke sollen intellektuelle Werte vermitteln, die einen bedeutenden Beitrag zur Lösung gesellschaftspolitischer Probleme und Konflikte leisten.
VI. Entwicklung der literarischen und gesellschaftspolitischen Vision
Hier wird die Entwicklungslinie der gesellschaftspolitischen Vision in den untersuchten Werken verfolgt.
VII. Zur Rezeption der vier Werke
Durch die Auseinandersetzung mit der negativen Kritik wird angestrebt, ihre Subjektivität darzulegen, damit der gesellschaftspolitische Wert der vier Werke enthüllt wird.
Six N-alkylpyridinium salts [CnPy](2)[MCl4] (n = 4 or 12 and M = Co, Cu, Zn) were synthesized, and their structure and thermal properties were studied. The [C4Py](2)[MCl4] compounds are monoclinic and crystallize in the space group P2(1)/n. The crystals of the longer chain analogues [C12Py](2)[MCl4] are triclinic and crystallize in the space group P (1) over bar. Above the melting temperature, all compounds are ionic liquids (ILs). The derivatives with the longer C12 chain exhibit liquid crystallinity and the shorter chain compounds only show a melting transition. Consistent with single-crystal analysis, electron paramagnetic resonance spectroscopy suggests that the [CuCl4](2-) ions in the Cu-based ILs have a distorted tetrahedral geometry.
Six N-alkylpyridinium salts [CnPy](2)[MCl4] (n = 4 or 12 and M = Co, Cu, Zn) were synthesized, and their structure and thermal properties were studied. The [C4Py](2)[MCl4] compounds are monoclinic and crystallize in the space group P2(1)/n. The crystals of the longer chain analogues [C12Py](2)[MCl4] are triclinic and crystallize in the space group P (1) over bar. Above the melting temperature, all compounds are ionic liquids (ILs). The derivatives with the longer C12 chain exhibit liquid crystallinity and the shorter chain compounds only show a melting transition. Consistent with single-crystal analysis, electron paramagnetic resonance spectroscopy suggests that the [CuCl4](2-) ions in the Cu-based ILs have a distorted tetrahedral geometry.
Pollination syndromes and their predictive power regarding actual plant-animal interactions have been controversially discussed in the past. We investigate pollination syndromes in Balsaminaceae, utilizing quantitative respectively categorical data sets of flower morphometry, signal and reward traits for 86 species to test for the effect of different types of data on the test patterns retrieved. Cluster Analyses of the floral traits are used in combination with independent pollinator observations. Based on quantitative data we retrieve seven clusters, six of them corresponding to plausible pollination syndromes and one additional, well-supported cluster comprising highly divergent floral architectures. This latter cluster represents a non-syndrome of flowers not segregated by the specific data set here used. Conversely, using categorical data we obtained only a rudimentary resolution of pollination syndromes, in line with several earlier studies. The results underscore that the use of functional, exactly quanitified trait data has the power to retrieve pollination syndromes circumscribed by the specific data used. Data quality can, however, not be replaced by sheer data volume. With this caveat, it is possible to identify pollination syndromes from large datasets and to reliably extrapolate them for taxa for which direct observations are unavailable.
Prospects for Cherenkov Telescope Array Observations of the Young Supernova Remnant RX J1713.7-3946
(2017)
We perform simulations for future Cherenkov Telescope Array (CTA) observations of RX J1713.7-3946, a young supernova remnant (SNR) and one of the brightest sources ever discovered in very high energy (VHE) gamma rays. Special attention is paid to exploring possible spatial (anti) correlations of gamma rays with emission at other wavelengths, in particular X-rays and CO/H I emission. We present a series of simulated images of RX J1713.7-3946 for CTA based on a set of observationally motivated models for the gamma-ray emission. In these models, VHE gamma rays produced by high-energy electrons are assumed to trace the nonthermal X-ray emission observed by XMM-Newton, whereas those originating from relativistic protons delineate the local gas distributions. The local atomic and molecular gas distributions are deduced by the NANTEN team from CO and H I observations. Our primary goal is to show how one can distinguish the emission mechanism(s) of the gamma rays (i.e., hadronic versus leptonic, or a mixture of the two) through information provided by their spatial distribution, spectra, and time variation. This work is the first attempt to quantitatively evaluate the capabilities of CTA to achieve various proposed scientific goals by observing this important cosmic particle accelerator.
Particle filters (also called sequential Monte Carlo methods) are widely used for state and parameter estimation problems in the context of nonlinear evolution equations. The recently proposed ensemble transform particle filter (ETPF) [S. Reich, SIAM T. Sci. Comput., 35, (2013), pp. A2013-A2014[ replaces the resampling step of a standard particle filter by a linear transformation which allows for a hybridization of particle filters with ensemble Kalman filters and renders the resulting hybrid filters applicable to spatially extended systems. However, the linear transformation step is computationally expensive and leads to an underestimation of the ensemble spread for small and moderate ensemble sizes. Here we address both of these shortcomings by developing second order accurate extensions of the ETPF. These extensions allow one in particular to replace the exact solution of a linear transport problem by its Sinkhorn approximation. It is also demonstrated that the nonlinear ensemble transform filter arises as a special case of our general framework. We illustrate the performance of the second-order accurate filters for the chaotic Lorenz-63 and Lorenz-96 models and a dynamic scene-viewing model. The numerical results for the Lorenz-63 and Lorenz-96 models demonstrate that significant accuracy improvements can be achieved in comparison to a standard ensemble Kalman filter and the ETPF for small to moderate ensemble sizes. The numerical results for the scene-viewing model reveal, on the other hand, that second-order corrections can lead to statistically inconsistent samples from the posterior parameter distribution.
Assimilation of pseudo-tree-ring-width observations into an atmospheric general circulation model
(2017)
Paleoclimate data assimilation (DA) is a promising technique to systematically combine the information from climate model simulations and proxy records. Here, we investigate the assimilation of tree-ring-width (TRW) chronologies into an atmospheric global climate model using ensemble Kalman filter (EnKF) techniques and a process-based tree-growth forward model as an observation operator. Our results, within a perfect-model experiment setting, indicate that the "online DA" approach did not outperform the "off-line" one, despite its considerable additional implementation complexity. On the other hand, it was observed that the nonlinear response of tree growth to surface temperature and soil moisture does deteriorate the operation of the time-averaged EnKF methodology. Moreover, for the first time we show that this skill loss appears significantly sensitive to the structure of the growth rate function, used to represent the principle of limiting factors (PLF) within the forward model. In general, our experiments showed that the error reduction achieved by assimilating pseudo-TRW chronologies is modulated by the magnitude of the yearly internal variability in themodel. This result might help the dendrochronology community to optimize their sampling efforts.
Assimilation of pseudo-tree-ring-width observations into an atmospheric general circulation model
(2017)
Paleoclimate data assimilation (DA) is a promising technique to systematically combine the information from climate model simulations and proxy records. Here, we investigate the assimilation of tree-ring-width (TRW) chronologies into an atmospheric global climate model using ensemble Kalman filter (EnKF) techniques and a process-based tree-growth forward model as an observation operator. Our results, within a perfect-model experiment setting, indicate that the "online DA" approach did not outperform the "off-line" one, despite its considerable additional implementation complexity. On the other hand, it was observed that the nonlinear response of tree growth to surface temperature and soil moisture does deteriorate the operation of the time-averaged EnKF methodology. Moreover, for the first time we show that this skill loss appears significantly sensitive to the structure of the growth rate function, used to represent the principle of limiting factors (PLF) within the forward model. In general, our experiments showed that the error reduction achieved by assimilating pseudo-TRW chronologies is modulated by the magnitude of the yearly internal variability in themodel. This result might help the dendrochronology community to optimize their sampling efforts.
This article considers Isabella Bird’s representation of medicine in Unbeaten Tracks in Japan (1880) and Journeys in Persia and Kurdistan (1891), the two books in which she engages most extensively with both local (Chinese/Islamic) and Western medical science and practice. I explore how Bird uses medicine to assert her narrative authority and define her travelling persona in opposition to local medical practitioners. I argue that her ambivalence and the unease she frequently expresses concerning medical practice (expressed particularly in her later adoption of the Persian appellation “Feringhi Hakīm” [European physician] to describe her work) serves as a means for her to negotiate the colonial and gendered pressures on Victorian medicine. While in Japan this attitude works to destabilise her hierarchical understanding of science and results in some acknowledgement of traditional Japanese traditions, in Persia it functions more to disguise her increasing collusion with overt British colonial ambitions.
For the processing of goal-directed actions, some accounts emphasize the importance of experience with the action or the agent. Other accounts stress the importance of agency cues. We investigated the impact of agency cues on 11-month-olds’ and adults’ goal anticipation for a grasping-action performed by a mechanical claw. With an eyetracker, we measured anticipations in two conditions, where the claw was displayed either with or without agency cues. In two experiments, 11-month-olds were predictive when agency cues were present, but reactive when no agency cues were presented. Adults were predictive in both conditions. Furthermore, 11-month-olds rapidly learned to predict the goal in the agency condition, but not in the mechanical condition. Adults’ predictions did not change across trials in the agency condition, but decelerated in the mechanical condition. Thus, agency cues and own action experience are important for infants’ and adults’ online processing of goal-directed actions by non-human agents.
The title compound was prepared by the reaction of 1,4,10,13-tetraoxa-7,16-diazacyclo-octadecane with 4-chloro-2-methyl-phenoxyacetic acid in a ratio of 1:2. The structure has been proved by the data of elemental analysis, IR spectroscopy, NMR ( 1 H, 13 C) technique and by X-ray diffraction analysis. Intermolecular hydrogen bonds between the azonium protons and oxygen atoms of the carboxylate groups were found. Immunoactive properties of the title compound have been screened. The compound has the ability to suppress spontaneous and Con A-stimulated cell proliferation in vitro and therefore can be considered as immunodepressant.
The predictions of two contrasting approaches to the acquisition of transitive relative clauses were tested within the same groups of German-speaking participants aged from 3 to 5 years old. The input frequency approach predicts that object relative clauses with inanimate heads (e.g., the pullover that the man is scratching) are comprehended earlier and more accurately than those with an animate head (e.g., the man that the boy is scratching). In contrast, the structural intervention approach predicts that object relative clauses with two full NP arguments mismatching in number (e.g., the man that the boys are scratching) are comprehended earlier and more accurately than those with number-matching NPs (e.g., the man that the boy is scratching). These approaches were tested in two steps. First, we ran a corpus analysis to ensure that object relative clauses with number-mismatching NPs are not more frequent than object relative clauses with number-matching NPs in child directed speech. Next, the comprehension of these structures was tested experimentally in 3-, 4-, and 5-year-olds respectively by means of a color naming task. By comparing the predictions of the two approaches within the same participant groups, we were able to uncover that the effects predicted by the input frequency and by the structural intervention approaches co-exist and that they both influence the performance of children on transitive relative clauses, but in a manner that is modulated by age. These results reveal a sensitivity to animacy mismatch already being demonstrated by 3-year-olds and show that animacy is initially deployed more reliably than number to interpret relative clauses correctly. In all age groups, the animacy mismatch appears to explain the performance of children, thus, showing that the comprehension of frequent object relative clauses is enhanced compared to the other conditions. Starting with 4-year-olds but especially in 5-year-olds, the number mismatch supported comprehension-a facilitation that is unlikely to be driven by input frequency. Once children fine-tune their sensitivity to verb agreement information around the age of four, they are also able to deploy number marking to overcome the intervention effects. This study highlights the importance of testing experimentally contrasting theoretical approaches in order to characterize the multifaceted, developmental nature of language acquisition.
The predictions of two contrasting approaches to the acquisition of transitive relative clauses were tested within the same groups of German-speaking participants aged from 3 to 5 years old. The input frequency approach predicts that object relative clauses with inanimate heads (e.g., the pullover that the man is scratching) are comprehended earlier and more accurately than those with an animate head (e.g., the man that the boy is scratching). In contrast, the structural intervention approach predicts that object relative clauses with two full NP arguments mismatching in number (e.g., the man that the boys are scratching) are comprehended earlier and more accurately than those with number-matching NPs (e.g., the man that the boy is scratching). These approaches were tested in two steps. First, we ran a corpus analysis to ensure that object relative clauses with number-mismatching NPs are not more frequent than object relative clauses with number-matching NPs in child directed speech. Next, the comprehension of these structures was tested experimentally in 3-, 4-, and 5-year-olds respectively by means of a color naming task. By comparing the predictions of the two approaches within the same participant groups, we were able to uncover that the effects predicted by the input frequency and by the structural intervention approaches co-exist and that they both influence the performance of children on transitive relative clauses, but in a manner that is modulated by age. These results reveal a sensitivity to animacy mismatch already being demonstrated by 3-year-olds and show that animacy is initially deployed more reliably than number to interpret relative clauses correctly. In all age groups, the animacy mismatch appears to explain the performance of children, thus, showing that the comprehension of frequent object relative clauses is enhanced compared to the other conditions. Starting with 4-year-olds but especially in 5-year-olds, the number mismatch supported comprehension—a facilitation that is unlikely to be driven by input frequency. Once children fine-tune their sensitivity to verb agreement information around the age of four, they are also able to deploy number marking to overcome the intervention effects. This study highlights the importance of testing experimentally contrasting theoretical approaches in order to characterize the multifaceted, developmental nature of language acquisition.
The predictions of two contrasting approaches to the acquisition of transitive relative clauses were tested within the same groups of German-speaking participants aged from 3 to 5 years old. The input frequency approach predicts that object relative clauses with inanimate heads (e.g., the pullover that the man is scratching) are comprehended earlier and more accurately than those with an animate head (e.g., the man that the boy is scratching). In contrast, the structural intervention approach predicts that object relative clauses with two full NP arguments mismatching in number (e.g., the man that the boys are scratching) are comprehended earlier and more accurately than those with number-matching NPs (e.g., the man that the boy is scratching). These approaches were tested in two steps. First, we ran a corpus analysis to ensure that object relative clauses with number-mismatching NPs are not more frequent than object relative clauses with number-matching NPs in child directed speech. Next, the comprehension of these structures was tested experimentally in 3-, 4-, and 5-year-olds respectively by means of a color naming task. By comparing the predictions of the two approaches within the same participant groups, we were able to uncover that the effects predicted by the input frequency and by the structural intervention approaches co-exist and that they both influence the performance of children on transitive relative clauses, but in a manner that is modulated by age. These results reveal a sensitivity to animacy mismatch already being demonstrated by 3-year-olds and show that animacy is initially deployed more reliably than number to interpret relative clauses correctly. In all age groups, the animacy mismatch appears to explain the performance of children, thus, showing that the comprehension of frequent object relative clauses is enhanced compared to the other conditions. Starting with 4-year-olds but especially in 5-year-olds, the number mismatch supported comprehension—a facilitation that is unlikely to be driven by input frequency. Once children fine-tune their sensitivity to verb agreement information around the age of four, they are also able to deploy number marking to overcome the intervention effects. This study highlights the importance of testing experimentally contrasting theoretical approaches in order to characterize the multifaceted, developmental nature of language acquisition.
Quality attributes of fruit determine its acceptability by the retailer and consumer. The objective of this work was to investigate the potential of absorption (μa) and reduced scattering (μs’) coefficients of European pear to analyze its fruit flesh firmness and soluble solids content (SSC). The absolute reference values, μa* (cm−1) and μs’* (cm−1), of pear were invasively measured, employing multi-spectral photon density wave (PDW) spectroscopy at preselected wavelengths of 515, 690, and 940 nm considering two batches of unripe and overripe fruit. On eight measuring dates during fruit development, μa and μs’ were analyzed non-destructively by means of laser light backscattering imaging (LLBI) at similar wavelengths of 532, 660, and 830 nm by means of fitting according to Farrell’s diffusion theory, using fix reference values of either μa* or μs’*. Both, the μa* and the μa as well as μs’* and μs’ showed similar trends. Considering the non-destructively measured data during fruit development, μa at 660 nm decreased 91 till 141 days after full bloom (dafb) from 1.49 cm−1 to 0.74 cm−1 due to chlorophyll degradation. At 830 nm, μa only slightly decreased from 0.41 cm−1 to 0.35 cm−1. The μs’ at all wavelengths revealed a decreasing trend as the fruit developed. The difference measured at 532 nm was most pronounced decreasing from 24 cm−1 to 10 cm−1, while at 660 nm and 830 nm values decreased from 15 cm−1 to 13 cm−1 and from 10 cm−1 to 8 cm−1, respectively. When building calibration models with partial least-squares regression analysis on the optical properties for non-destructive analysis of the fruit SSC, μa at 532 nm and 830 nm resulted in a correlation coefficient of R = 0.66, however, showing high measuring uncertainty. The combination of all three wavelengths gave an enhanced, encouraging R = 0.89 for firmness analysis using μs’ in the freshly picked fruit.
The cross-linguistic finding of greater demands in processing object relatives as compared to subject relatives in individuals with aphasia and non-brain-damaged speakers has been explained within the Relativized Minimality approach. Based on this account, the asymmetry is attributed to an element intervening between the moved element and its extraction site in object relatives, but not in subject relatives. Moreover, it has been proposed that processing of object relatives is facilitated if the intervening and the moved elements differ in their internal feature structure. The present study investigates these predictions in German-speaking individuals with aphasia and a group of control participants by combining the visual world eye-tracking methodology with an auditory referent identification task. Our results provide support for the Relativized Minimality approach. Particularly, the degree of featural distinctness was shown to modulate the occurrence of the effects in aphasia. We claim that, due to reduced processing capacities, individuals with aphasia need a higher degree of featural dissimilarity to distinguish the moved from the intervening element in object relatives to overcome their syntactic deficit. (C) 2017 Elsevier Ltd. All rights reserved.
The temporal dynamics of climate processes are spread across different timescales and, as such, the study of these processes at only one selected timescale might not reveal the complete mechanisms and interactions within and between the (sub-) processes. To capture the non-linear interactions between climatic events, the method of event synchronization has found increasing attention recently. The main drawback with the present estimation of event synchronization is its restriction to analysing the time series at one reference timescale only. The study of event synchronization at multiple scales would be of great interest to comprehend the dynamics of the investigated climate processes. In this paper, the wavelet-based multi-scale event synchronization (MSES) method is proposed by combining the wavelet transform and event synchronization. Wavelets are used extensively to comprehend multi-scale processes and the dynamics of processes across various timescales. The proposed method allows the study of spatio-temporal patterns across different timescales. The method is tested on synthetic and real-world time series in order to check its replicability and applicability. The results indicate that MSES is able to capture relationships that exist between processes at different timescales.
The temporal dynamics of climate processes are spread across different timescales and, as such, the study of these processes at only one selected timescale might not reveal the complete mechanisms and interactions within and between the (sub-) processes. To capture the non-linear interactions between climatic events, the method of event synchronization has found increasing attention recently. The main drawback with the present estimation of event synchronization is its restriction to analysing the time series at one reference timescale only. The study of event synchronization at multiple scales would be of great interest to comprehend the dynamics of the investigated climate processes. In this paper, the wavelet-based multi-scale event synchronization (MSES) method is proposed by combining the wavelet transform and event synchronization. Wavelets are used extensively to comprehend multi-scale processes and the dynamics of processes across various timescales. The proposed method allows the study of spatio-temporal patterns across different timescales. The method is tested on synthetic and real-world time series in order to check its replicability and applicability. The results indicate that MSES is able to capture relationships that exist between processes at different timescales.
Natural products and their semisynthetic derivatives are an important source of drugs for the pharmaceutical industry. Bacteria are prolific producers of natural products and encode a vast diversity of natural product biosynthetic gene clusters. However, much of this diversity is inaccessible to natural product discovery. Here, we use a combination of phylogenomic analysis of the microviridin biosynthetic pathway and chemo-enzymatic synthesis of bioinformatically predicted microviridins to yield new protease inhibitors. Phylogenomic analysis demonstrated that microviridin biosynthetic gene clusters occur across the bacterial domain and encode three distinct subtypes of precursor peptides. Our analysis shed light on the evolution of microviridin biosynthesis and enabled prioritization of their chemo-enzymatic production. Targeted one-pot synthesis of four microviridins encoded by the cyanobacterium Cyanothece sp. PCC 7822 identified a set of novel and potent serine protease inhibitors, the most active of which had an IC50 value of 21.5 nM. This study advances the genome mining techniques available for natural product discovery and obviates the need to culture bacteria.
Aims. We present an extensive study of the BL Lac object Mrk 501 based on a data set collected during the multi-instrument campaign spanning from 2009 March 15 to 2009 August 1, which includes, among other instruments, MAGIC, VERITAS, Whipple 10 m, and Fermi-LAT to cover the gamma-ray range from 0.1 GeV to 20 TeV; RXTE and Swift to cover wavelengths from UV to hard X-rays; and GASP-WEBT, which provides coverage of radio and optical wavelengths. Optical polarization measurements were provided for a fraction of the campaign by the Steward and St. Petersburg observatories. We evaluate the variability of the source and interband correlations, the gamma-ray flaring activity occurring in May 2009, and interpret the results within two synchrotron self-Compton (SSC) scenarios. Methods. The multiband variability observed during the full campaign is addressed in terms of the fractional variability, and the possible correlations are studied by calculating the discrete correlation function for each pair of energy bands where the significance was evaluated with dedicated Monte Carlo simulations. The space of SSC model parameters is probed following a dedicated grid-scan strategy, allowing for a wide range of models to be tested and offering a study of the degeneracy of model-to-data agreement in the individual model parameters, hence providing a less biased interpretation than the "single-curve SSC model adjustment" typically reported in the literature. Results. We find an increase in the fractional variability with energy, while no significant interband correlations of flux changes are found on the basis of the acquired data set. The SSC model grid-scan shows that the flaring activity around May 22 cannot be modeled adequately with a one-zone SSC scenario (using an electron energy distribution with two breaks), while it can be suitably described within a two (independent) zone SSC scenario. Here, one zone is responsible for the quiescent emission from the averaged 4.5-month observing period, while the other one, which is spatially separated from the first, dominates the flaring emission occurring at X-rays and very-high-energy (> 100 GeV, VHE) gamma-rays. The flaring activity from May 1, which coincides with a rotation of the electric vector polarization angle (EVPA), cannot be satisfactorily reproduced by either a one-zone or a two-independent-zone SSC model, yet this is partially affected by the lack of strictly simultaneous observations and the presence of large flux changes on sub-hour timescales (detected at VHE gamma rays). Conclusions. The higher variability in the VHE emission and lack of correlation with the X-ray emission indicate that, at least during the 4.5-month observing campaign in 2009, the highest energy (and most variable) electrons that are responsible for the VHE gamma rays do not make a dominant contribution to the similar to 1 keV emission. Alternatively, there could be a very variable component contributing to the VHE gamma-ray emission in addition to that coming from the SSC scenario. The studies with our dedicated SSC grid-scan show that there is some degeneracy in both the one-zone and the two-zone SSC scenarios probed, with several combinations of model parameters yielding a similar model-to-data agreement, and some parameters better constrained than others. The observed gamma-ray flaring activity, with the EVPA rotation coincident with the first gamma-ray flare, resembles those reported previously for low frequency peaked blazars, hence suggesting that there are many similarities in the flaring mechanisms of blazars with different jet properties.
The German Enlightenment
(2017)
The term Enlightenment (or Aufklärung) remains heavily contested. Even when historians delimit the remit of the concept, assigning it to a particular historical period rather than to an intellectual or moral programme, the public resonance of the Enlightenment remains high and problematic—especially when equated in an essentialist manner with modernity or some core values of ‘the West’. This Forum has been convened to discuss recent research on the Enlightenment in Germany, different views of the term and its ideological use in public discourse outside academia (and sometimes within it).
Climate or land use?
(2017)
This study intends to contribute to the ongoing discussion on whether land use and land cover changes (LULC) or climate trends have the major influence on the observed increase of flood magnitudes in the Sahel. A simulation-based approach is used for attributing the observed trends to the postulated drivers. For this purpose, the ecohydrological model SWIM (Soil and Water Integrated Model) with a new, dynamic LULC module was set up for the Sahelian part of the Niger River until Niamey, including the main tributaries Sirba and Goroul. The model was driven with observed, reanalyzed climate and LULC data for the years 1950–2009. In order to quantify the shares of influence, one simulation was carried out with constant land cover as of 1950, and one including LULC. As quantitative measure, the gradients of the simulated trends were compared to the observed trend. The modeling studies showed that for the Sirba River only the simulation which included LULC was able to reproduce the observed trend. The simulation without LULC showed a positive trend for flood magnitudes, but underestimated the trend significantly. For the Goroul River and the local flood of the Niger River at Niamey, the simulations were only partly able to reproduce the observed trend. In conclusion, the new LULC module enabled some first quantitative insights into the relative influence of LULC and climatic changes. For the Sirba catchment, the results imply that LULC and climatic changes contribute in roughly equal shares to the observed increase in flooding. For the other parts of the subcatchment, the results are less clear but show, that climatic changes and LULC are drivers for the flood increase; however their shares cannot be quantified. Based on these modeling results, we argue for a two-pillar adaptation strategy to reduce current and future flood risk: Flood mitigation for reducing LULC-induced flood increase, and flood adaptation for a general reduction of flood vulnerability.
Sedimentary lipid biomarkers have become widely used tools for reconstructing past climatic and ecological changes due to their ubiquitous occurrence in lake sediments. In particular, the hydrogen isotopic composition (expressed as delta D values) of leaf wax lipids derived from terrestrial plants has been a focus of research during the last two decades and the understanding of competing environmental and plant physiological factors influencing the delta D values has greatly improved. Comparatively less attention has been paid to lipid biomarkers derived from aquatic plants, although these compounds are abundant in many lacustrine sediments. We therefore conducted a field and laboratory experiment to study the effect of salinity and groundwater discharge on the isotopic composition of aquatic plant biomarkers. We analyzed samples of the common submerged plant species, Potamogeton pectinatus (sago pondweed), which has a wide geographic distribution and can tolerate high salinity. We tested the effect of groundwater discharge (characterized by more negative delta D values relative to lake water) and salinity on the delta D values of n-alkanes from P. pectinatus by comparing plants (i) collected from the oligotrophic freshwater Lake Stechlin (Germany) at shallow littoral depth from locations with and without groundwater discharge, and (ii) plants grown from tubers collected from the eutrophic Lake Muggelsee in nutrient solution at four salinity levels. Isotopically depleted groundwater did not have a significant influence on the delta D values of n-alkanes in Lake Stechlin P. pectinatus and calculated isotopic fractionation factors epsilon(l/w) between lake water and n-alkanes averaged -137 +/- 9%(n-C-23), -136 +/- 7%(n-C-25) and -131 +/- 6%(n-C-27), respectively. Similar epsilon values were calculated for plants from Lake Muggelsee grown in freshwater nutrient solution (-134 +/- 11% for n-C-23), while greater fractionation was observed at increased salinity values of 10 (163 +/- 12%) and 15(-172 +/- 15%). We therefore suggest an average e value of -136 +/- 9% between source water and the major n-alkanes in P. pectinatus grown under freshwater conditions. Our results demonstrate that isotopic fractionation can increase by 30-40% at salinity values 10 and 15. These results could be explained either by inhibited plant growth at higher salinity, or by metabolic adaptation to salt stress that remain to be elucidated. A potential salinity effect on dD values of aquatic lipids requires further examination, since this would impact on the interpretation of downcore isotopic data in paleohydrologic studies. (C) 2017 Elsevier Ltd. All rights reserved.
CPS and the Worker
(2017)
The idea of interlinked, sensor-augmented, self-governing Cyber Physical System (CPS) production processes is gaining momentum. At the same time, the impact of this concept on the workforce remains surprisingly vague. This can be explained by the fact that man is not at the centre of these developments and—even more importantly—automation is geared towards eliminating human activity. Based on the first views in the 1980s, the label of the “process worker” assumed an almost exclusive focus on control and maintenance tasks for this new type of worker in the automated factory. Recent experiences show, however, that as long as robots are not self-learning, man will be the template for these machines and we can already notice the emerging parallelism of fully automated production lines and human workshops. The changing nature of the workforce will gain further momentum if one depicts new, open formats of production. Here, the worker will have to assume new roles in reconfiguring the production processes.
Although it has become common practice to build applications based on the reuse of existing components or services, technical complexity and semantic challenges constitute barriers to ensuring a successful and wide reuse of components and services. In the geospatial application domain, the barriers are self-evident due to heterogeneous geographic data, a lack of interoperability and complex analysis processes.
Constructing workflows manually and discovering proper services and data that match user intents and preferences is difficult and time-consuming especially for users who are not trained in software development. Furthermore, considering the multi-objective nature of environmental modeling for the assessment of climate change impacts and the various types of geospatial data (e.g., formats, scales, and georeferencing systems) increases the complexity challenges.
Automatic service composition approaches that provide semantics-based assistance in the process of workflow design have proven to be a solution to overcome these challenges and have become a frequent demand especially by end users who are not IT experts. In this light, the major contributions of this thesis are:
(i) Simplification of service reuse and workflow design of applications for climate impact analysis by following the eXtreme Model-Driven Development (XMDD) paradigm.
(ii) Design of a semantic domain model for climate impact analysis applications that comprises specifically designed services, ontologies that provide domain-specific vocabulary for referring to types and services, and the input/output annotation of the services using the terms defined in the ontologies.
(iii) Application of a constraint-driven method for the automatic composition of workflows for analyzing the impacts of sea-level rise. The application scenario demonstrates the impact of domain modeling decisions on the results and the performance of the synthesis algorithm.
Agricultural landscapes safeguard ecosystem services (ES) and biodiversity upon which human well-being depends. However, only a fraction of these services are generally considered in land management decisions, resulting in trade-offs and societally inefficient solutions. The TEEB Study (The Economics of Ecosystems and Biodiversity) spearheaded the development of assessments of the economic significance of ES and biodiversity. Several national TEEB follow-ups have compiled case studies and derived targeted policy advice. By synthesizing insights from "Natural Capital Germany - TEEB DE" and focusing on rural areas, the objectives of this study were (i) to explore causes of the continued decline of ES and biodiversity, (ii) to introduce case studies exemplifying the economic significance of ES and biodiversity in land use decisions, and (iii) to synthesize key recommendations for policy, planning and management. Our findings indicate that the continued decrease of ES and biodiversity in Germany can be explained by implementation deficits within a well-established nature conservation system. Three case studies on grassland protection, the establishment of riverbank buffer zones and water-sensitive farming illustrate that an economic perspective can convey recognition of the values of ES and biodiversity. We conclude with suggestions for enhanced consideration, improved conservation and sustainable use of ES and biodiversity. (C) 2017 Elsevier B.V. All rights reserved.
Objective:Common genetic variants in the gene encoding uromodulin (UMOD) have been associated with renal function, blood pressure (BP) and hypertension. We investigated the associations between an important single nucleotide polymorphism (SNP) in UMOD, that is rs12917707-G>T, and estimated glomerular filtration rate (eGFR), BP and cardiac organ damage as determined by echocardiography in patients with arterial hypertension.Methods:A cohort of 1218 treated high-risk patients (mean age 58.5 years, 83% men) with documented cardiovascular disease (81% with coronary heart disease) was analysed.Results:The mean values for 24-h SBP and DBP were 124.714.7 and 73.9 +/- 9.4mmHg; mean eGFR was 77.5 +/- 18.3ml/min per 1.73m(2), mean left ventricular ejection fraction was 59.3 +/- 9.9% and mean left ventricular mass index in men and women was 53.9 +/- 23.2 and 54.9 +/- 23.7g/m(2.7) with 50.4% of patients having left ventricular hypertrophy. A significant association between rs12917707 and eGFR was observed with T-allele carriers showing significantly higher eGFR values (+2.6ml/min per 1.73m(2), P=0.006) than noncarriers. This SNP associated also with left atrial diameter (P=0.007); homozygous carriers of the T-allele had smaller left atrial diameter (-1.5mm) than other genotype groups (P=0.040). No significant associations between rs12917707 and other cardiac or BP phenotypes were observed.Conclusions:These findings extend the previously documented role of UMOD for renal function also to treated high-risk patients with arterial hypertension and reveal a novel association with left atrial remodelling and thus a potential cardiorenal link modulated by UMOD.
The substantial booms and busts in agricultural prices marked by extreme events across commodities lead to heated debates about the effects of speculative trading on commodity price fluctuations. This study proposes a new approach to understanding extreme events and boom-bust processes in agricultural markets. Using weekly futures data for twelve indexed agricultural commodities during 2006 to 2016, we find that extreme price changes, located in the 10% tails of the distribution, cluster across agricultural markets. We then implement a multinomial logit model to investigate which factors are associated with the propagation of extreme events. Specifically, we disentangle three transmission conduits. (1) The macroeconomic conduit captures the possibility that the synchronized extreme price events are generated by business-cycle driven demand shifts mainly in emerging economies. (2) The financial conduit refers to potential links between extreme returns and the increasing flow of money from financial participants into agricultural futures markets. (3) Finally, the energy conduit accounts for possible spillover effects due to oil price shocks. Our results indicate an important role of managed money positions and oil prices while the real demand channel remains mostly insignificant. (C) 2017 Elsevier Ltd. All rights reserved.
Successful delivery of the United Nations sustainable development goals and implementation of the Paris Agreement requires technologies that utilize a wide range of minerals in vast quantities. Metal recycling and technological change will contribute to sustaining supply, but mining must continue and grow for the foreseeable future to ensure that such minerals remain available to industry. New links are needed between existing institutional frameworks to oversee responsible sourcing of minerals, trajectories for mineral exploration, environmental practices, and consumer awareness of the effects of consumption. Here we present, through analysis of a comprehensive set of data and demand forecasts, an interdisciplinary perspective on how best to ensure ecologically viable continuity of global mineral supply over the coming decades.
Selection of initial points, the number of clusters and finding proper clusters centers are still the main challenge in clustering processes. In this paper, we suggest genetic algorithm based method which searches several solution spaces simultaneously. The solution spaces are population groups consisting of elements with similar structure. Elements in a group have the same size, while elements in different groups are of different sizes. The proposed algorithm processes the population in groups of chromosomes with one gene, two genes to k genes. These genes hold corresponding information about the cluster centers. In the proposed method, the crossover and mutation operators can accept parents with different sizes; this can lead to versatility in population and information transfer among sub-populations. We implemented the proposed method and evaluated its performance against some random datasets and the Ruspini dataset as well. The experimental results show that the proposed method could effectively determine the appropriate number of clusters and recognize their centers. Overall this research implies that using heterogeneous population in the genetic algorithm can lead to better results.
In sub-Saharan Africa, infectious diseases and malnutrition constitute the main health problems in children, while adolescents and adults are increasingly facing cardio-metabolic conditions. Among adolescents as the largest population group in this region, we investigated the co-occurrence of infectious diseases, malnutrition and cardio-metabolic risk factors (CRFs), and evaluated demographic, socio-economic and medical risk factors for these entities. In a cross-sectional study among 188 adolescents in rural Ghana, malarial infection, common infectious diseases and Body Mass Index were assessed. We measured ferritin, C-reactive protein, retinol, fasting glucose and blood pressure. Socio-demographic data were documented. We analyzed the proportions (95% confidence interval, CI) and the cooccurrence of infectious diseases (malaria, other common diseases), malnutrition (underweight, stunting, iron deficiency, vitamin A deficiency [VAD]), and CRFs (overweight, obesity, impaired fasting glucose, hypertension). In logistic regression, odds ratios (OR) and 95% CIs were calculated for the associations with socio-demographic factors. In this Ghanaian population (age range, 14.4-15.5 years; males, 50%), the proportions were for infectious diseases 45% (95% CI: 38-52%), for malnutrition 50% (43-57%) and for CRFs 16% (11- 21%). Infectious diseases and malnutrition frequently co-existed (28%; 21-34%). Specifically, VAD increased the odds of non-malarial infectious diseases 3-fold (95% CI: 1.03, 10.19). Overlap of CRFs with infectious diseases (6%; 2-9%) or with malnutrition (7%; 3-11%) was also present. Male gender and low socio-economic status increased the odds of infectious diseases and malnutrition, respectively. Malarial infection, chronic malnutrition and VAD remain the predominant health problems among these Ghanaian adolescents. Investigating the relationships with evolving CRFs is warranted.
We present very-high-energy gamma-ray observations of the BL Lac object 1ES 2344+514 taken by the Very Energetic Radiation Imaging Telescope Array System between 2007 and 2015. 1ES 2344+514 is detected with a statistical significance above the background of 20.8 sigma in 47.2 h (livetime) of observations, making this the most comprehensive very-high-energy study of 1ES 2344+514 to date. Using these observations, the temporal properties of 1ES 2344+514 are studied on short and long times-scales. We fit a constant-flux model to nightly and seasonally binned light curves and apply a fractional variability test to determine the stability of the source on different time-scales. We reject the constant-flux model for the 2007-2008 and 2014-2015 nightly binned light curves and for the long-term seasonally binned light curve at the > 3 sigma level. The spectra of the time-averaged emission before and after correction for attenuation by the extragalactic background light are obtained. The observed time-averaged spectrum above 200 GeV is satisfactorily fitted (x(2)/NDF = 7.89/6) by a power-law function with an index Gamma = 2.46 +/- 0.06(stat) +/- 0.20(sys) and extends to at least 8 TeV. The extragalactic-backgroundlight-deabsorbed spectrum is adequately fit (x(2)/NDF = 6.73/6) by a power-law function with an index Gamma = 2.15 +/- 0.06(stat) +/- 0.20(sys) while an F-test indicates that the power law with an exponential cut-off function provides a marginally better fit (x(2)/NDF = 2.56/5) at the 2.1 sigma level. The source location is found to be consistent with the published radio location and its spatial extent is consistent with a point source.
Vitamin E inhibits the propagation of lipid peroxidation and helps protecting photosystem II from photoinhibition, but little is known about its possible role in plant response to Pi availability. Here, we aimed at examining the effect of vitamin E deficiency in Arabidopsis thaliana vte mutants on phytohormone contents and the expression of transcription factors in plants exposed to contrasting Pi availability. Plants were subjected to two doses of Pi, either unprimed (controls) or previously exposed to low Pi (primed). In the wild type, alpha-tocopherol contents increased significantly in response to repeated periods of low Pi, which was paralleled by increased growth, indicative of a priming effect. This growth-stimulating effect was, however, abolished in vte mutants. Hormonal profiling revealed significant effects of Pi availability, priming and genotype on the contents of jasmonates and salicylates; remarkably, vte mutants showed enhanced accumulation of both hormones under low Pi. Furthermore, expression profiling of 1,880 transcription factors by qRT-PCR revealed a pronounced effect of priming on the transcript levels of 45 transcription factors mainly associated with growth and stress in wild-type plants in response to low Pi availability; while distinct differences in the transcriptional response were detected in vte mutants. We conclude that alpha-tocopherol plays a major role in the response of plants to Pi availability not only by protecting plants from photo-oxidative stress, but also by exerting a control over growth-and defense-related transcriptional reprogramming and hormonal modulation.
Context:
Massive binaries play a crucial role in the Universe. Knowing the distributions of their orbital parameters is important for a wide range of topics from stellar feedback to binary evolution channels and from the distribution of supernova types to gravitational wave progenitors, yet no direct measurements exist outside the Milky Way.
Aims:
The Tarantula Massive Binary Monitoring project was designed to help fill this gap by obtaining multi-epoch radial velocity (RV) monitoring of 102 massive binaries in the 30 Doradus region.
Methods:
In this paper we analyze 32 FLAMES/GIRAFFE observations of 93 O- and 7 B-type binaries. We performed a Fourier analysis and obtained orbital solutions for 82 systems: 51 single-lined (SB1) and 31 double-lined (SB2) spectroscopic binaries.
Results:
Overall, the binary fraction and orbital properties across the 30 Doradus region are found to be similar to existing Galactic samples. This indicates that within these domains environmental effects are of second order in shaping the properties of massive binary systems. A small difference is found in the distribution of orbital periods, which is slightly flatter (in log space) in 30 Doradus than in the Galaxy, although this may be compatible within error estimates and differences in the fitting methodology. Also, orbital periods in 30 Doradus can be as short as 1.1 d, somewhat shorter than seen in Galactic samples. Equal mass binaries (q> 0.95) in 30 Doradus are all found outside NGC 2070, the central association that surrounds R136a, the very young and massive cluster at 30 Doradus’s core. Most of the differences, albeit small, are compatible with expectations from binary evolution. One outstanding exception, however, is the fact that earlier spectral types (O2–O7) tend to have shorter orbital periods than later spectral types (O9.2–O9.7).
Conclusions:
Our results point to a relative universality of the incidence rate of massive binaries and their orbital properties in the metallicity range from solar (Z⊙) to about half solar. This provides the first direct constraints on massive binary properties in massive star-forming galaxies at the Universe’s peak of star formation at redshifts z ~ 1 to 2 which are estimated to have Z ~ 0.5 Z⊙.
We elaborate a boundary Fourier method for studying an analogue of the Hilbert problem for analytic functions within the framework of generalised Cauchy-Riemann equations. The boundary value problem need not satisfy the Shapiro-Lopatinskij condition and so it fails to be Fredholm in Sobolev spaces. We show a solvability condition of the Hilbert problem, which looks like those for ill-posed problems, and construct an explicit formula for approximate solutions.
תקציר
מצוות הפריון הינה אחת מן המצוות החשובות ביהדות ומגדירה במובנים רבים את מהות קיומו של האדם היהודי הדתי. זוגות דתיים אשר סובלים מבעיית פריון נקרעים לא פעם בין מחוייבותם הדתית והלחץ החברתי בקהילתם לבין אי יכולתם להביא ילדים לעולם בדרך טבעית. החל מאמצע המאה ה 20- הפכו טכנולוגיות פריון רפואיות לנגישות לציבור הרחב בישראל ובעולם והובילו למהפכה חברתית אשר אפשרה לזוגות חשוכי ילדים להגשים את חלומם בפעם הראשונה ולהפוך להורים. פריצת דרך רפואית זו לא נעלמה מעיני הציבור הדתי על זרמיו השונים וגרמה לטלטלה בתפיסת עולמם של מנהיגיהם, אשר נדרשו לתת מענה הלכתי הולם המאזן בין רווחת קהילותיהם לבין שמירה על ערכי ומצוות הדת היהודית. על רקע תמורות אלו התפתח שיח הלכתי ואקדמי חשוב ומעניין באשר למקומה של טכנולוגיה מודרנית בחברה המתנהלת על פי קודים מסורתיים. עם זאת, הדיאלוג החי המתקיים בין מנהיגי היהדות לבין קהילותיהם, אשר מתועד כאוסף שאלות ותשובות (שו"ת) לבעיות הלכתיות אקטואליות בתחום הפריון, לא נחקר דיו.
עבודתנו עוסקת במחקר ספרות השו"ת ובגישת פוסקי ההלכה להסתייעות בטכנולוגיית ההזרעה המלאכותית ובטיפולי פוריות חדשניים נוספים שהתפתחו בעקבותיה כגון הפריה חוץ גופית, פונדקאות ותרומת ביציות. העבודה סוקרת את התגבשות ועיצוב ההלכה בשאלה זו, כפי שעולה מספרות השו"ת החל מתקופת הראשונים (המאות ה 11- עד ה- 16 ) ועד לפוסקים מתקופת האחרונים (המאה ה- 16 ואילך), ומתמקדת בעיקר בתקופה המודרנית של המאה האחרונה. במרכז העבודה יעמדו מעמדם ההלכתי של האם והוולד בעקבות שימוש בהזרעה והפריה מלאכותית וכן השלכותיהן ההלכתיות של השימוש הרפואי בזרע.
תרומתו של מחקר זה הינה בהצגת וניתוח התמודדות הפוסקים עם העימות הערכי וההלכתי שמעוררות תמורות במבנה המשפחה ובדפוסי הורות מסורתיים כתוצאה משימוש הולך וגובר בטכנולוגיות פריון מתקדמות בחברה המודרנית. יתר על כן, מחקר זה מרחיב את הדיון ההלכתי אל מעבר לעמדות הפוסקים ביהדות האורתודוקסית, הנצמדים לעקרונות ההלכה ההיסטורית, ומציג לראשונה אף את קשת הדעות של רבנים המשתייכים לזרמי היהדות המתקדמת והקונסרבטיבית, הדוגלים בפיתוח ההלכה והתאמתה למציאות החיים המשתנה. כך, מעניקה עבודת מחקר זו תמונה שלמה ומקיפה יותר באשר להתמודדות הרבנים עם שאלת ההזרעה המלאכותית ומציגה את רב גוניותה של ההלכה כפי שמשתקפת בזרמי היהדות השונים בישראל ובתפוצות.
העבודה מחולקת לשישה חלקים אשר יפורטו בקצרה להלן.
חלק ראשון - מבוא לשאלת ההזרעה המלאכותית בספרות השו"ת
חלק זה מהווה מבוא והקדמה תיאורטית ומחקרית לשאלת ההזרעה המלאכותית ומטרתו לצייד את הקורא ברקע ההיסטורי ובכלים המחקריים הדרושים להמשך העבודה. הפרק הראשון סוקר מצוות דתיות והשקפות תרבותיות בנוגע לילודה בחברה היהודית ואילו הפרק השני מניח יסודות מתודולוגיים והיסטוריים הנחוצים לחקר שאלת ההזרעה המלאכותית בספרות השו"ת.
פרק ראשון - מצוות דתיות והשקפות תרבותיות בנוגע לילודה בחברה היהודית
פרק זה מציג את המשנה האידיאולוגית העומדת בבסיס ההצדקה ההלכתית להתרתם של טיפולי הפוריות. הפרק דן בחשיבות מצוות הפריון כפי שעולה ממקורות הלכתיים קדומים וברקע ההיסטורי והתרבותי למרכזיותה של מצווה זו ומצוות נלוות לה בדת היהודית. הפרק מדגים כיצד עיצבה חשיבות המצווה את דפוס המשפחה היהודית לאורך ההיסטוריה ועד לימינו ומסתיים בדיון קצר בשאלות רפואיות מוסריות העולות מהנגשת טכנולוגיות פריון מתקדמות במדינת ישראל המודרנית.
פרק שני - יסודות מתודולוגיים והיסטוריים בחקר שאלת ההזרעה המלאכותית בספרות השו"ת
בפרק זה מוצגים תחילה מטרות ושיטות המחקר אשר נבחרו לשם ניתוח הפסיקה בשאלת ההזרעה המלאכותית. מכיוון שהעבודה עוסקת בשאלה רפואית חדשנית והשפעתה על העולם הדתי, יערך מחקר זה תוך שימוש בניתוח רב מימדי המשלב מספר שיטות מחקר ובראשן השיטה הדוגמטית-היסטורית, כמו גם בניתוח ביקורתי של שיקולי המדיניות העומדים בבסיס שיקולי הפוסקים לפי אסוכלת הריאליזים ההלכתי. לאחר מכן נסקרים ונידונים המקורות ההיסטוריים העיקריים אשר עוסקים בהתעברות על טבעית באמבט או באמצעות שכיבה על סדינים והעומדים בבסיס הכרעות הפוסקים בהשלכות הזרעה מלאכותית על מעמדם ההלכתי של האישה והילוד.
חלק שני- ספרות השו"ת האורתודוקסית בשאלת הזרעה מלאכותית מן הבעל
חלקו שני של המחקר עוסק בניתוח ספרות השו"ת האורתודוקסית בשאלת הזרעה מלאכותית מן הבעל ובוחן את התפתחותו הרעיונית של איסור השחתת זרע ואת עמדות הפוסקים בשאלת הזרעה מלאכותית מן הבעל כפי שנידונה בספרות השו"ת.
פרק ראשון - התפתחותו הרעיונית של איסור השחתת זרע
בפרק זה נסקרים מקורותיו ההיסטוריים של האיסור להשחתת זרע. איסור זה נושק לכל תחומי חייו של הזוג הדתי ובעיקר לתחום המיניות והפריון ובעל השפעה מהותית על מגבלות הצניעות שהוחלו בעקבותיו על המיניות הגברית. קיים ויכוח בין החוקרים האם נובע האיסור מן המקורות העתיקים כגון התלמוד או לחילופין התעצם בעקבות החמרות הרבנים. מחקרינו מציע כי האפשרות השניה היא הסבירה יותר. חכמי התלמוד מפגינים גישה מקלה כלפי האיסור אך מביעים סלידה מהוצאת זרע לבטלה מתוך חשיבה חסידית או אמונה כי עיסוק בעינוג מיני עצמי עלול להסיט את האדם מקיום מצוות הפריון. לעומת זאת, בספרות הקבלה ובמיוחד בזוהר ניכרת החמרה במימדי האיסור החודרת מאוחר יותר אל עולם ההלכה.
פרק שני - דיון בהזרעה מן הבעל בספרות השו"ת
הפרק דן בפסיקותיהם של רבנים בולטים בזרם האורתודוקסי בשאלת ההזרעה מן הבעל. בספרות השו"ת האורתודוקסית ניכרת השפעתו של איסור הוצאת זרע לבטלה על שיקולי הפוסקים באם להתיר את הטיפול בהזרעה מלאכותית מן הבעל. פוסקים מקלים כגון הרבנים פיינשטיין, נבנצל ויוסף מייחסים משקל רב יותר לחשיבות מצוות הפריון ומצמצמים בשל כך את תחולת האיסור. לעומתם, פוסקים מחמירים ובראשם הרבנים טננבוים, קוק, עוזיאל, הדאיה ולדנברג מתנגדים לטיפולי פוריות מחשש השחתת זרע ובשל השלכותיה הרוחניות של העבירה על האיסור. שאלה מהותית נוספת בשיח ההלכתי בה נחלקו הרבנים הינה באשר לאפשרות קיומה של מצוות הפריה והרביה באמצעות הריון שהושג בסיוע רפואי. פוסקים מדור האחרונים, כגון הרבנים טננבוים, סגל ואזולאי (החיד"א), ובעקבותיהם פוסקים בולטים במאה ה- 20 וה- 21 כמו הרבנים עוזיאל, הדאיה, ולדנברג וקניבסקי סברו כי ניתן לקיים את המצווה באופן טבעי בלבד. לעומת זאת, הרבנים נבנצל, יוסף, וינברג ואוירבך ייחסו חשיבות רבה יותר לכוונת העושה ולתוצאה המיוחלת של ההריון אשר מגשימה לדעתם את הרציונל העומד בבסיס מצוות הפרייה הרבייה ובמצוות ישוב העולם.
שאלה נוספת המתעוררת בעניין הזרעה מן הבעל ונידונה בפרק זה עוסקת בבעיית העקרות ההלכתית. התעקשות הרבנים לשמור על הלכות הנידה במתכונתן המסורתית חושפת נשים דתיות לאי ודאות באשר לטהרתן ומכפיפה את חיי המין והפריון של משפחות שלמות למרות הסמכות הרבנית.
חלק שלישי- ספרות השו"ת האורתודוקסית בשאלת הזרעה מלאכותית מתורם
חלקו השלישי של המחקר עוסק בדיון ההלכתי האורתודוקסי בשאלת ההזרעה המלאכותית מתורם יהודי או נוכרי לאישה נשואה. מרבית הפוסקים הסתייגו מתרומת זרע לאישה נשואה מתורם יהודי כמו גם מנוכרי משיקולים הלכתיים ואידיאולוגיים.
פרק ראשון - שאלת ההזרעה המלאכותית מתורם יהודי
תרומת זרע מתורם יהודי זר מעלה חששות הלכתיים רבים לגבי מעמדה ההלכתי של האישה כגון ניאוף וקיום מצוות הייבום והחליצה. כמו כן הועלו חששות לגבי יחוסו וכשרותו ההלכתית של הקטין כגון חשש ממזרות, גילוי עריות בין ילדי התורם, פגיעה במעמד הכהונה ובעיות בתחום המעמד האישי בשל אי ודאות לגבי זהות התורם. בנוסף, משליכה הכרעה בשאלות אלה על זכאות הקטין לזכויות סוציאליות המגיעות לו מאביו, כגון הזכות למזונות ולירושה. פסיקת ההלכה במאה האחרונה אימצה את עמדתו של הרב פיינשטיין, לפיה רק הריון הנובע ממגע מיני ישיר בין אישה נשואה לגבר זר, בניגוד להזרעה מלאכותית, יכול לפגוע במעמד האישה והילוד. עם זאת, פוסקים רבים אסרו לבצע הזרעה מלאכותית מגבר יהודי מטעמי זהירות, בגין חששות אלו.
פרק שני - הזרעה מלאכותית מתורם לא יהודי לאישה נשואה
על אף שבמקרה של תרומת זרע מנוכרי נעדר הילוד יחוס לאביו הנוכרי וכשרותו נקבעת על פי מעמד האם בלבד, מסתייגים פוסקים רבים מן הפעולה. הפוסקים מונים טיעונים רבים לאיסור תרומת זרע מגבר נוכרי וביניהם חילול השם, פגיעה בביצוע מנהג הייבום והחליצה, ספקות לגבי זכויות הירושה, עידוד ההפקרות המינית ופגיעה ביציבות התא המשפחתי המסורתי. בנוסף חוששים הם מבלבול לגבי זהות אבי הילוד ופגיעה במעמד הכהונה. במהלך המאה ה- 20 ניכרת מגמה בקרב פוסקים העוסקים בקבלה לייחוס תכונות שליליות לזרע נוכרי, אשר עוברות לילוד ובאופן זה פוגעות בקדושת העם היהודי. מעבר לשאלות ההלכתיות מועלים בפרק זה קשיים אתיים אשר מעוררת תרומת זרע אנונימית, המונעת מן הילוד לברר את שורשיו הביולוגיים.
חלק רביעי- יחס הפסיקה האורתודוקסית לשינויים במבנה המשפחה המסורתית
בעקבות שימוש בטכנולוגיות פריון חלק זה מנתח את יחס הפסיקה האורתודוקסית לשינויים במבנה המשפחה המסורתית בעקבות שימוש בטכנולוגיות פריון ומורכב משלושה פרקים: הזרעה מלאכותית לאישה פנויה, הפריה חוץ גופית והקמת משפחה אלטרנטיבית בפרספקטיבה הלכתית אורתודוקסית.
פרק ראשון - הזרעה מלאכותית לאישה פנויה
המוסכמה ההלכתית הינה כי ילדה של אישה פנויה לא ייחשב לממזר, אפילו אם אביו הביולוגי הוא יהודי. למרות זאת אסרו פוסקים מסויימים על הזרעה מלאכותית במקרה זה בגין חששות לייחוס הילוד, גילוי עריות וגזילת ירושת שאר האחים. חלק מן הפוסקים קוראים לאסור הזרעה מלאכותית לאישה פנויה בשם טובת הילד ולא מסיבות הלכתיות. אפשרות נוספת אשר השלכותיה ההלכתיות נידונות בפרק זה הינה ביצוע הזרעה מלאכותית באישה רווקה או אלמנה באמצעות שימוש בזרעו של אדם שנפטר. חשוב לציין כי השימוש בטכנולוגיה זו שנוי במחלוקת בקרב הרבנים בגין החשיבות אותה מייחסת היהדות לערך כבוד המת.
פרק שני - הפריה חוץ גופית
הפריית מבחנה יכולה להתבצע בין בני זוג נשואים בסיוע או ללא היזקקות לתרומת ביצית או זרע. פוסקים אשר התירו את השימוש בטכנולוגיה זו הביעו את חששותיהם בנוגע להשלכותיה ההלכתיות של הפריה החוץ גופית בשל הקושי לפקח על התהליך, הנעשה מחוץ לגוף האדם. מתנגדי הפריית המבחנה סברו כי היא מתערבת במלאכת הבריאה האלוהית ועשויה לדרדר את האנושות מבחינה מוסרית לתכנון ולשיבוט בני אדם.
הפריה חוץ גופית מעוררות שאלות הלכתיות חדשניות ובראשן שאלת הגדרת האמהות, כגון במקרי פונדקאות ותרומת ביציות, מהן הסתייגו מרבית פוסקי הדור במאה ה 20- . הקביעה שאומצה בשיח ההלכתי העכשווי גורסת כי אמו של התינוק תהיה האישה שילדה אותו, גם אם נולד מתרומת ביצית. הכרעה זו מובלעת ברציונל החוקים המסדירים את הפונדקאות במדינת ישראל ואשר מטילים מגבלות הלכתיות על בחירת הפונדקאית לשם מניעת חשש ממזרות או שאלה לגבי יהדותו של הילוד.
פרק שלישי - הקמת משפחה אלטרנטיבית בפרספקטיבה הלכתית אורתודוקסית
קיימת בעיה הלכתית מהותית במיסוד הקשר החד-מיני ביהדות האורתודוקסית. ספרות השו"ת האורתודוקסית אינה עוסקת במפורש בשאלת השימוש בהזרעה מלאכותית לצורך הקמת המשפחה החד- מינית. עם זאת, ניתן ללמוד רבות על גישת האורתודוקסיה משו"תים עכשוויים העוסקים בתופעת ההומוסקסואליות ובקיום מצוות הפריון במקרה זה. הדעה הרווחת היום בקרב הפוסקים הינה כי קשר חד- מיני אסור, כמו גם מיסודו וקיום מצוות פרו ורבו במסגרת זו. בשל כך ניתן להסיק כי הרבנים לא יתירו שימוש בהזרעה מלאכותית לצורך קיום מצוות הפריון במשפחה חד-מינית.
חלק חמישי- עמדת רבני הזרם רפורמי והקונסרבטיבי בשאלת ההזרעה המלאכותית
חלק זה מתמקד בזרמי היהדות הרפורמית והקונסרבטיבית ומציג את עמדות רבני זרמים אלו בעניין ההזרעה המלאכותית תוך עימותן עם עמדות פוסקים אורתודוקסיים.
פרק ראשון - עמדת הרבנות הרפורמית בשאלת ההזרעה המלאכותית
חשיבות מצוות הפריון מודגשת בספרות השו"ת הרפורמית, אולם טיפולי פוריות אינם מתפרשים כדרך היחידה לקיומה. על מנת שלא לפגוע במרקם החיים המשפחתי מוצעת לא אחת חלופת האימוץ לטיפולי פוריות מייגעים, תרומת זרע והיזקקות לפונדקאות ותרומת ביציות. שאלת השחתת הזרע, המעסיקה רבות את רבני הזרם האורתודוקסי, כמעט שאינה נידונה על ידי רבני הזרם הרפורמי. באשר לשאלות של כשרות וייחוס, רווחת הדעה בקרב רבנים רפורמיים בולטים כגון הרב הומולקה ורומיין, כי מעמד הממזרות איננו רלוונטי עוד בימינו ולכן ממילא לא נשקפת לילד הסכנה שזכויותיו הדתיות ייפגעו.
ועד הרבנים הרפורמיים התיר לחבריו לפעול לפי שיקול דעתם בעניין עריכת טקס נישואין דתי בין בני זוג בני אותו המין, תוך הדגשת הויכוח הפנימי בתנועה ומורת הרוח הקיימת מצד הזרמים האחרים ביהדות.
פרק שני - עמדת הרבנות הקונסרבטיבית בשאלת ההזרעה המלאכותית
עמדת רבני היהדות הקונסרבטיבית גורסת כי טיפולי פוריות מהווים רשות, אך אינם בגדר חובה עבור זוגות הרוצים לקיים את מצוות הפריה והרבייה ומתקשים בכך. בדומה לביטולה של גזירת הממזרות בזרם הרפורמי, בוטל מעמד זה לאחרונה גם ביהדות הקונסרבטיבית. אוננות במסגרת טיפולי פוריות הינה מותרת ואיננה מוגדרת כהשחתת זרע לבטלה ואף מותרת גם לשם תרומת זרע של יהודי לאישה לא יהודיה. כמו בזרם הרפורמי גם כאן מונחת אופציית האימוץ על סדר היום.
כנסת הרבנים הקונסרבטיבים בארצות הברית קיבלה החלטה ברוב זעום להכרה אזרחית בהומוסקסואלים, אך עם זאת השאירה על כנו את האיסור לקדש זוגות אלה. אין בהחלטה זו הכרה הלכתית בזוגיות החד-מינית אלא קבלתם החברתית של זוגות אלה ועידודם להשתלב בקהילות הקונסרבטיביות.
חלק שישי - סיכום ודיון בהשלכות המחקר
בחלקו השישי והאחרון בעבודת מחקר זו נסכם ונדון בהשלכותיה האתיות והגלובליולת של הפסיקה ההלכית בשאלה הנידונה.
כפי שניתן לראות מעבודת מחקר זו, הרבנים האורתודוקסיים מסתמכים בהכרעותיהם בעיקר על שיקולים הלכתיים ופחות על שיקולים אתיים ואוניברסליים. מחד, מסתייגים פוסקים אורתודוקסיים מסויימים משימוש לרעה בטיפולי פוריות, אך מאידך מוכנים הם בשם עקרונות דתיים להתיר שימוש בטכנולוגיות אלו במקרים שאינם מצריכים זאת משיקולים רפואיים. במיוחד בולט העדר התייחסותם של הפוסקים האורתודוקסיים לשיקולים מוסריים חברתיים, כמו גם לרצונה ולרווחתה של האישה העוברת טיפולי פוריות. לעומתם מביעים רבני הזרם הרפורמי והקונסרבטיבי את דאגתם להשלכותיהם של טיפולים אלו על נשים הנזקקות להתערבות רפואית מעין זו לשם התעברות ואלו העובדות בתעשיית הפריון. יש לציין כי הדיון ההלכתי עוסק בהיבט צר בלבד של שאלת ההזרעה המלאכותית ואינו נוגע ברבות מן השאלות המורכבות שמעוררות טכנולוגיות פריון מתקדמות. עם זאת הדיון ההלכתי הינו חשוב ביותר ומציף אף שאלות נוספות בדבר הסכנה הצפויה מהפיכתן של טכנולוגיות אלה לכלי שרת בידי אידאולוגיות דתיות או פוליטיות.
Sediment resuspension represents a key process in all natural aquatic systems, owing to its role in nutrient cycling and transport of potential contaminants. Although suspended solids are generally accepted as an important quality parameter, current monitoring programs cover quantitative aspects only. Established methodologies do not provide information on origin, fate, and risks associated with uncontrolled inputs of solids in waters. Here we discuss the analytical approaches to assess the occurrence and ecological relevance of resuspended particulate matter in freshwaters, with a focus on the dynamics of associated contaminants and microorganisms. Triggered by the identification of specific physical-chemical traits and community structure of particle-associated microorganisms, recent findings suggest that a quantitative determination of microorganisms can be reasonably used to trace the origin of particulate matter by means of nucleic acid-based assays in different aquatic systems.
Mildred Harnack, geb. Fish, stammte ursprünglich aus Milwaukee, Wisconsin. Zusammen mit ihrem Ehemann Arvid Harnack zog sie nach Deutschland und lebte seit 1930 in Berlin. Hier lehrte die Literaturwissenschaftlerin an der Friedrich-Wilhelms-Universität (heute Humboldt-Universität) und am Berliner Abendgymnasium (heute Peter A. Silbermann-Schule). Bereits kurz nach der Machtübernahme von Adolf Hitler hatte sich um das Ehepaar Harnack ein Kreis von Freunden gebildet, der gegen die Herrschaft der Nationalsozialisten opponierte. Dazu zählten auch Karl Behrens und Bodo Schlösinger, die beide Schüler Mildred Harnacks am Berliner Abendgymnasium waren. Mildred Harnack konnte mit Hilfe ihrer Kontakte zur amerikanischen Botschaft ihren Schülern im nationalsozialistischen Deutschland ansonsten nicht zugängliche Informationen besorgen.
Aufgrund von Funkkontakten des Freundeskreises zur Sowjetunion wurde die Gruppe von den Nationalsozialisten Rote Kapelle genannt – „rot“ bezog sich auf deren linke Haltung und mit „Kapelle“ wurden Funker assoziiert, die wie Pianisten in einer Kapelle spielen. Der Berliner Oppositionszirkel umfasste bis zu seiner Zerschlagung durch die Nationalsozialisten etwa 150 Personen verschiedenster Berufsgruppen, unterschiedlicher parteipolitischer Einstellungen und Konfessionen. Die Gruppe verfertigte oppositionelle Flugblätter und lieferte Informationen an die amerikanische Botschaft sowie an die Sowjetunion. Mildred Harnack wurde – wie viele ihrer Mitstreiterinnen und Mitstreiter – nach ihrer Verhaftung vom Reichskriegsgericht zum Tode verurteilt und am 16. Februar 1943 in Plötzensee guillotiniert.
In diesem Band stellen Studierende der Universität Potsdam sowie Hörerinnen und Hörer der Peter A. Silbermann-Schule (Berlin) nach einem kurzen Überblick zum Widerstand gegen den Nationalsozialismus in Deutschland das Netzwerk der Roten Kapelle sowie die Biographien von Mildred Harnack und ihren Schülern Karl Behrens und Bodo Schlösinger vom Berliner Abendgymnasium eindrücklich vor.
The formation of the Pamir is a key component of the India-Asia collision with major implications for lithospheric processes, plateau formation, land-sea configurations and associated climate changes. Although the formation of the Pamir is traditionally linked to Cenozoic processes associated with the India-Asia collision, the contribution of the Mesozoic tectonic evolution remains poorly understood. The Pamir was formed by the suturing of Gondwanan terranes to the south margin of Eurasia, however, the timing and tectonic mechanisms associated with this Mesozoic accretion remain poorly constrained. These processes are recorded by several igneous belts within these terranes, which are not well studied. Within the Southern Pamir, the Albian-Turonian volcanic rocks and comagmatic plutons of the Kyzylrabat Igneous Complex (KIC) provide an important and still unconstrained record of the Pamir evolution. Here we provide the age, origin and the geodynamic setting of the KIC volcanics by studying their petrology, zircon U-Pb geochronology, geochemistry and isotope composition.17 samples from the KIC volcanics yield U-Pb ages spanning from 92 to 110 Ma. The volcanics are intermediate to acidic in composition (SiO2 = 56-69 wt%) and exhibit high-K calc-alkaline and shoshonitic affinity (K2O/Na2O = 12.2 wt%). They show enrichment in LILE and LREE and depletion in HFSE and HREE with negative Ta, Ti and Nb anomalies, suggesting an arc-related tectonic setting for their formation. Low sNd(t) values (from 9.1 to 4.7), relatively high Sr-87/Sr-86(i) ratios (0.7069-0.7096) and broad range of zircon stif values (from 22.6 to 1.5) suggest a mixture of different magma sources. These features suggest that volcanics were derived by crustal under- or intraplating of an enriched subduction-related mantle shoshonitic magmas, by heating and partial melting of the lower crust, and by mixing of both magma components. Our results further imply that the KIC volcanics represent a shoshonitic suite typical of an evolution from active continental arc to post-collisional setting with a steepening of the Benioff zone and thickening of the crust toward the back-arc. This setting is best explained by the subduction- collision transition along the Shyok suture due to accretion of the Kohistan island arc to the Karakoram. This suggests that a significant part of the crustal shortening and thickening accommodated in the Pamir occurred in the Mesozoic before the India-Asia collision with implications for regional tectonic models. This further suggests the Pamir was already a major topographic feature with potentially important paleoclimate forcing such as the monsoonal circulation. (C) 2017 International Association for Gondwana Research. Published by Elsevier B.V. All rights reserved.
Galaxies are among the most complex systems that can currently be modelled with a computer. A realistic simulation must take into account cosmology and gravitation as well as effects of plasma, nuclear, and particle physics that occur on very different time, length, and energy scales. The Milky Way is the ideal test bench for such simulations, because we can observe millions of its individual stars whose kinematics and chemical composition are records of the evolution of our Galaxy. Thanks to the advent of multi-object spectroscopic surveys, we can systematically study stellar populations in a much larger volume of the Milky Way. While the wealth of new data will certainly revolutionise our picture of the formation and evolution of our Galaxy and galaxies in general, the big-data era of Galactic astronomy also confronts us with new observational, theoretical, and computational challenges.
This thesis aims at finding new observational constraints to test Milky-Way models, primarily based on infra-red spectroscopy from the Apache Point Observatory Galactic Evolution Experiment (APOGEE) and asteroseismic data from the CoRoT mission. We compare our findings with chemical-evolution models and more sophisticated chemodynamical simulations. In particular we use the new powerful technique of combining asteroseismic and spectroscopic observations that allows us to test the time dimension of such models for the first time. With CoRoT and APOGEE (CoRoGEE) we can infer much more precise ages for distant field red-giant stars, opening up a new window for Galactic archaeology.
Another important aspect of this work is the forward-simulation approach that we pursued when interpreting these complex datasets and comparing them to chemodynamical models.
The first part of the thesis contains the first chemodynamical study conducted with the APOGEE survey. Our sample comprises more than 20,000 red-giant stars located within 6 kpc from the Sun, and thus greatly enlarges the Galactic volume covered with high-resolution spectroscopic observations. Because APOGEE is much less affected by interstellar dust extinction, the sample covers the disc regions very close to the Galactic plane that are typically avoided by optical surveys. This allows us to investigate the chemo-kinematic properties of the Milky Way's thin disc outside the solar vicinity. We measure, for the first time with high-resolution data, the radial metallicity gradient of the disc as a function of distance from the Galactic plane, demonstrating that the gradient flattens and even changes its sign for mid-plane distances greater than 1 kpc.
Furthermore, we detect a gap between the high- and low-[$\alpha$/Fe] sequences in the chemical-abundance diagram (associated with the thin and thick disc) that unlike in previous surveys can hardly be explained by selection effects. Using 6D kinematic information, we also present chemical-abundance diagrams cleaned from stars on kinematically hot orbits. The data allow us to confirm without doubt that the scale length of the (chemically-defined) thick disc is significantly shorter than that of the thin disc.
In the second part, we present our results of the first combination of asteroseismic and spectroscopic data in the context of Galactic Archaeology. We analyse APOGEE follow-up observations of 606 solar-like oscillating red giants in two CoRoT fields close to the Galactic plane. These stars cover a large radial range of the Galactic disc (4.5 kpc $\lesssim R_{\rm Gal}\lesssim15$ kpc) and a large age baseline (0.5 Gyr $\lesssim \tau\lesssim$ 13 Gyr), allowing us to study the age- and radius-dependence of the [$\alpha$/Fe] vs. [Fe/H] distributions. We find that the age distribution of the high-[$\alpha$/Fe] sequence appears to be broader than expected from a monolithically-formed old thick disc that stopped to form stars 10 Gyr ago. In particular, we discover a significant population of apparently young, [$\alpha$/Fe]-rich stars in the CoRoGEE data whose existence cannot be explained by standard chemical-evolution models. These peculiar stars are much more abundant in the inner CoRoT field LRc01 than in the outer-disc field LRc01, suggesting that at least part of this population has a chemical-evolution rather than a stellar-evolution origin, possibly due to a peculiar chemical-enrichment history of the inner disc. We also find that strong radial migration is needed to explain the abundance of super-metal-rich stars in the outer disc.
Finally, we use the CoRoGEE sample to study the time evolution of the radial metallicity gradient in the thin disc, an observable that has been the subject of observational and theoretical debate for more than 20 years. By dividing the CoRoGEE dataset into six age bins, performing a careful statistical analysis of the radial [Fe/H], [O/H], and [Mg/Fe] distributions, and accounting for the biases introduced by the observation strategy, we obtain reliable gradient measurements. The slope of the radial [Fe/H] gradient of the young red-giant population ($-0.058\pm0.008$ [stat.] $\pm0.003$ [syst.] dex/kpc) is consistent with recent Cepheid data. For the age range of $1-4$ Gyr, the gradient steepens slightly ($-0.066\pm0.007\pm0.002$ dex/kpc), before flattening again to reach a value of $\sim-0.03$ dex/kpc for stars with ages between 6 and 10 Gyr. This age dependence of the [Fe/H] gradient can be explained by a nearly constant negative [Fe/H] gradient of $\sim-0.07$ dex/kpc in the interstellar medium over the past 10 Gyr, together with stellar heating and migration. Radial migration also offers a new explanation for the puzzling observation that intermediate-age open clusters in the solar vicinity (unlike field stars) tend to have higher metallicities than their younger counterparts. We suggest that non-migrating clusters are more likely to be kinematically disrupted, which creates a bias towards high-metallicity migrators from the inner disc and may even steepen the intermediate-age cluster abundance gradient.
Cultural generality versus specificity of media violence effects on aggression was examined in seven countries (Australia, China, Croatia, Germany, Japan, Romania, the United States). Participants reported aggressive behaviors, media use habits, and several other known risk and protective factors for aggression. Across nations, exposure to violent screen media was positively associated with aggression. This effect was partially mediated by aggressive cognitions and empathy. The media violence effect on aggression remained significant even after statistically controlling a number of relevant risk and protective factors (e.g., abusive parenting, peer delinquency), and was similar in magnitude to effects of other risk factors. In support of the cumulative risk model, joint effects of different risk factors on aggressive behavior in each culture were larger than effects of any individual risk factor.
We present a fluorescence excitation-emission-matrix spectrometer with superior data acquisition rates over previous instruments. Light from a white light emitting diode (LED) source is dispersed onto a digital micromirror array (DMA) and encoded using binary n-size Walsh functions ("barcodes"). The encoded excitation light is used to irradiate the liquid sample and its fluorescence is dispersed and detected using a conventional array spectrometer. After exposure to excitation light encoded in n different ways, the 2-dimensional excitation-emission-matrix (EEM) spectrum is obtained by inverse Hadamard transformation. Using this technique we examined the kinetics of the fluorescence of rhodamine B as a function of temperature and the acid-driven demetalation of chlorophyll into pheophytin-a. For these experiments, EEM spectra with 31 excitation channels and 2048 emission channels were recorded every 15 s. In total, data from over 3000 EEM spectra were included in this report. It is shown that the increase in data acquisition rate can be as high as [{n(n + 1)}/2]-fold over conventional EEM spectrometers. Spectral acquisition rates of more than two spectra per second were demonstrated.
Entsorgt und ausgeblendet
(2017)
Die Kluft zwischen Ost- und Westdeutschen ist in den vergangenen Jahren nicht schmaler geworden. Bis heute sind Ostdeutsche nur selten in Führungspositionen in Wirtschaft, Politik und Medien anzutreffen. Offensichtlich ist die Herstellung der inneren Einheit ein schwieriger, langwieriger Prozess der Annäherung, der womöglich nie vollständig vollzogen werden kann. Diesem Prozess nachzugehen und zu zeigen, wie sich Eliten vor dem Hintergrund gesellschaftlicher Umbrüche positionieren, welche Voraussetzungen die beteiligten Generationen und Elitenvertreter in Ost- und Westdeutschland mitbrachten, in welcher Form sie tangiert waren und welche medialen Perspektiven sich daran knüpfen, ist Ziel dieses Buches. Denn der Umgang mit den ostdeutschen Eliten berührt unsere Zukunft.
Befreiung oder Gewalt?
(2017)
Moving Forces
(2017)
Throughout a large part of the twentieth century, the body was interpreted as a field of signs, the meaning of which pointed to an unconscious dimension. At the height of the popularity of structuralism, Jacques Lacan deemed the unconscious to be “structured like a language.” Starting in the early 1990s, however, a deep shift occurred in the way the body was interpreted. A new movement cast tremendous doubt on the hegemony of language and instead advocated a performative, pictorial, and affective approach — the so-called material turn — which encompassed all of these. In the words of Karen Barad, this turn inquired as to why meaning, history, and truth are assigned to language only, whereas the movements of materiality are given less prominence: “How did language come to be more trustworthy than matter? Why are language and culture granted their own agency and historicity while matter is figured as passive and immutable?” With this shift toward the material, bodies began to be seen in a different light and their materiality understood as something that follows its own laws and movements, which cannot be understood exclusively in terms of social-cultural codes. Instead, these laws and movements call into question the very dichotomies of nature/culture and body/spirit.
Ecology of Affect
(2017)
The way we conceive the human today is particularly affected by the shifts in media technology during the 20th century. Affect emerges as the new liminal concept that renders the body compatible in novel ways with the technology and politics of media. By ways of a relational reorganization the organic end technological life is condensed in a new, intense way to an ecology of affects.
The phrase form and function was established in architecture and biology and refers to the idea that form and functionality are closely correlated, influence each other, and co-evolve. We suggest transferring this idea to hydrological systems to separate and analyze their two main characteristics: their form, which is equivalent to the spatial structure and static properties, and their function, equivalent to internal responses and hydrological behavior. While this approach is not particularly new to hydrological field research, we want to employ this concept to explicitly pursue the question of what information is most advantageous to understand a hydrological system. We applied this concept to subsurface flow within a hillslope, with a methodological focus on function: we conducted observations during a natural storm event and followed this with a hillslope-scale irrigation experiment. The results are used to infer hydrological processes of the monitored system. Based on these findings, the explanatory power and conclusiveness of the data are discussed. The measurements included basic hydrological monitoring methods, like piezometers, soil moisture, and discharge measurements. These were accompanied by isotope sampling and a novel application of 2-D time-lapse GPR (ground-penetrating radar). The main finding regarding the processes in the hillslope was that preferential flow paths were established quickly, despite unsaturated conditions. These flow paths also caused a detectable signal in the catchment response following a natural rainfall event, showing that these processes are relevant also at the catchment scale. Thus, we conclude that response observations (dynamics and patterns, i.e., indicators of function) were well suited to describing processes at the observational scale. Especially the use of 2-D time-lapse GPR measurements, providing detailed subsurface response patterns, as well as the combination of stream-centered and hillslope-centered approaches, allowed us to link processes and put them in a larger context. Transfer to other scales beyond observational scale and generalizations, however, rely on the knowledge of structures (form) and remain speculative. The complementary approach with a methodological focus on form (i.e., structure exploration) is presented and discussed in the companion paper by Jackisch et al. (2017).
The phrase form and function was established in architecture and biology and refers to the idea that form and functionality are closely correlated, influence each other, and co-evolve. We suggest transferring this idea to hydrological systems to separate and analyze their two main characteristics: their form, which is equivalent to the spatial structure and static properties, and their function, equivalent to internal responses and hydrological behavior. While this approach is not particularly new to hydrological field research, we want to employ this concept to explicitly pursue the question of what information is most advantageous to understand a hydrological system. We applied this concept to subsurface flow within a hillslope, with a methodological focus on function: we conducted observations during a natural storm event and followed this with a hillslope-scale irrigation experiment. The results are used to infer hydrological processes of the monitored system. Based on these findings, the explanatory power and conclusiveness of the data are discussed. The measurements included basic hydrological monitoring methods, like piezometers, soil moisture, and discharge measurements. These were accompanied by isotope sampling and a novel application of 2-D time-lapse GPR (ground-penetrating radar). The main finding regarding the processes in the hillslope was that preferential flow paths were established quickly, despite unsaturated conditions. These flow paths also caused a detectable signal in the catchment response following a natural rainfall event, showing that these processes are relevant also at the catchment scale. Thus, we conclude that response observations (dynamics and patterns, i.e., indicators of function) were well suited to describing processes at the observational scale. Especially the use of 2-D time-lapse GPR measurements, providing detailed subsurface response patterns, as well as the combination of stream-centered and hillslope-centered approaches, allowed us to link processes and put them in a larger context. Transfer to other scales beyond observational scale and generalizations, however, rely on the knowledge of structures (form) and remain speculative. The complementary approach with a methodological focus on form (i.e., structure exploration) is presented and discussed in the companion paper by Jackisch et al. (2017).
HESS J1826-130
(2017)
HESS J1826-130 is an unidentified hard spectrum source discovered by H.E.S.S. along the Galactic plane, the spectral index being Gamma = 1.6 with an exponential cut-off at about 12 TeV. While the source does not have a clear counterpart at longer wavelengths, the very hard spectrum emission at TeV energies implies that electrons or protons accelerated up to several hundreds of TeV are responsible for the emission. In the hadronic case, the VHE emission can be produced by runaway cosmic-rays colliding with the dense molecular clouds spatially coincident with the H.E.S.S. source.
Chemotactic motion in a chemical gradient is an essential cellular function that controls many processes in the living world. For a better understanding and more detailed modelling of the underlying mechanisms of chemotaxis, quantitative investigations in controlled environments are needed. We developed a setup that allows us to separately address the dependencies of the chemotactic motion on the average background concentration and on the gradient steepness of the chemoattractant. In particular, both the background concentration and the gradient steepness can be kept constant at the position of the cell while it moves along in the gradient direction. This is achieved by generating a well-defined chemoattractant gradient using flow photolysis. In this approach, the chemoattractant is released by a light-induced reaction from a caged precursor in a microfluidic flow chamber upstream of the cell. The flow photolysis approach is combined with an automated real-time cell tracker that determines changes in the cell position and triggers movement of the microscope stage such that the cell motion is compensated and the cell remains at the same position in the gradient profile. The gradient profile can be either determined experimentally using a caged fluorescent dye or may be alternatively determined by numerical solutions of the corresponding physical model. To demonstrate the function of this adaptive microfluidic gradient generator, we compare the chemotactic motion of Dictyostelium discoideum cells in a static gradient and in a gradient that adapts to the position of the moving cell. Published by AIP Publishing.
Irradiance from sunlight changes in a sinusoidal manner during the day, with irregular fluctuations due to clouds, and light-dark shifts at dawn and dusk are gradual. Experiments in controlled environments typically expose plants to constant irradiance during the day and abrupt light-dark transitions. To compare the effects on metabolism of sunlight versus artificial light regimes, Arabidopsis thaliana plants were grown in a naturally illuminated greenhouse around the vernal equinox, and in controlled environment chambers with a 12-h photoperiod and either constant or sinusoidal light profiles, using either white fluorescent tubes or light-emitting diodes (LEDs) tuned to a sunlight-like spectrum as the light source. Rosettes were sampled throughout a 24-h diurnal cycle for metabolite analysis. The diurnal metabolite profiles revealed that carbon and nitrogen metabolism differed significantly between sunlight and artificial light conditions. The variability of sunlight within and between days could be a factor underlying these differences. Pairwise comparisons of the artificial light sources (fluorescent versus LED) or the light profiles (constant versus sinusoidal) showed much smaller differences. The data indicate that energy-efficient LED lighting is an acceptable alternative to fluorescent lights, but results obtained from plants grown with either type of artificial lighting might not be representative of natural conditions.
Innovationen sind wie ein Motor, der unser ökonomisches, soziales und ge-sellschaftliches Leben antreibt und laufend verändert. Ob in der Medizin-technik, Luft- und Raumfahrt, Energiegewinnung, im Netz oder in der Schule: In allen Bereichen sorgen Innovationen für die stetige Weiterent-wicklung unser Gesellschaft. Bernd Meier hat die Bedeutung von Innova-tionen und innovativem Denken für die technische Bildung und Schule früh erkannt. Mit einer kurzen Rückschau auf sein Wirken hinsichtlich der Be-deutung von Innovationen für die technische und ökonomische Bildung soll ein wichtiger Bereich seiner Arbeit gewürdigt werden. Zu Beginn wird der Innovationsbegriff allgemein umrissen und dann mit Blick auf Schule präzi-siert. Danach wird dargestellt, welchen Stellenwert die Thematik Innovation und Technologie nicht nur in den Publikationen von Bernd Meier, sondern auch in seinen Lehrkonzeptionen eingenommen hat. Im Anschluss daran wird diskutiert, warum es gerade im Bildungsbereich so schwer ist, innova-tiv zu sein oder dauerhaft Innovationen durchzusetzen.1 Der Beitrag endet mit einem Ausblick, inwiefern Innovationen auch in Zukunft für Schule und das Fach Wirtschaft-Arbeit-Technik (kurz: WAT) eine wichtige Thematik darstellen sollten.
Der Band versammelt 21 Beiträge, die unter dem Titel "Technische Bildung und berufliche Orientierung im Wandel" aus Anlass der Emeritierung von Prof. Dr. paed. habil Bernd Meier, Professur für Technologie und Berufliche Orientierung an der Wirtschafts- und Sozialwissenschaftlichen Fakultät der Universität Potsdam, auf einem Kolloquium 2017 gehalten wurden.
In a recent article in this journal, Ahrne, Brunsson, and Seidl (2016) suggest a definition of organization as a ‘decided social order’ composed of five elements (membership, rules, hierarchies, monitoring, and sanctions) which rest on decisions. ‘Partial organization’ uses only one or a few of these decidable elements while ‘complete organization’ uses them all. Such decided orders may also occur outside formal organizations, as the authors observe. Although we appreciate the idea of improving our understanding of organization(s) in modern society, we believe that Ahrne, Brunsson, and Seidl's suggestion jeopardizes the concept of organization by blurring its specific meaning. As the authors already draw on the work of Niklas Luhmann, we propose taking this exploration a step further and the potential of systems theory more seriously. Organizational analysis would then be able to retain a distinctive notion of formal organization on the one hand while benefiting from an encompassing theory of modern society on the other. With this extended conceptual framework, we would expect to gain a deeper understanding of how organizations implement and shape different societal realms as well as mediate between their particular logics, and, not least, how they are related to non-organizational social forms (e.g. families).
The Star Excursion Balance Test (SEBT) is effective in measuring dynamic postural control (DPC). This research aimed to determine whether DPC measured by the SEBT in young athletes (YA) with back pain (BP) is different from those without BP (NBP). 53 BP YA and 53 NBP YA matched for age, height, weight, training years, training sessions/week and training minutes/session were studied. Participants performed 4 practice trials after which 3 measurements in the anterior, posteromedial and posterolateral SEBT reach directions were recorded. Normalized reach distance was analyzed using the mean of all 3 measurements. There was no statistical significant difference (p > 0.05) between the reach distance of BP (87.2 ± 5.3, 82.4 ± 8.2, 78.7 ± 8.1) and NBP (87.8 ± 5.6, 82.4 ± 8.0, 80.0 ± 8.8) in the anterior, posteromedial and posterolateral directions respectively. DPC in YA with BP, as assessed by the SEBT, was not different from NBP YA.
Over the last few decades, the methodology for the identification of customary international law (CIL) has been changing. Both elements of CIL – practice and opinio juris – have assumed novel and broader forms, as noted in the Reports of the Special Rapporteur of the International Law Commission (2013, 2014, 2015, 2016). This paper discusses these Reports and the draft conclusions, and reaction by States in the Sixth Committee of the United Nations General Assembly (UNGA), highlighting the areas of consensus and contestation. This ties to the analysis of the main doctrinal positions, with special attention being given to the two elements of CIL, and the role of the UNGA resolutions. The underlying motivation is to assess the real or perceived crisis of CIL, and the author develops the broader argument maintaining that in order to retain unity within international law, the internal limits of CIL must be carefully asserted.
The rule of law is the cornerstone of the international legal system. This paper shows, through analysis of intergovernmental instruments, statements made by representatives of States, and negotiation records, that the rule of law at the United Nations has become increasingly contested in the past years. More precisely, the argument builds on the process of integrating the notion of the rule of law into the Sustainable Development Goals, adopted in September 2015 in the document Transforming our world: the 2030 Agenda for Sustainable Development. The main sections set out the background of the rule of law debate at the UN, the elements of the rule of law at the goal- and target-levels in the 2030 Agenda – especially in the SDG 16 –, and evaluate whether the rule of law in this context may be viewed as a normative and universal foundation of international law. The paper concludes, with reflections drawn from the process leading up to the 2030 Agenda and the final outcome document that the rule of law – or at least strong and precise formulations of the concept – may be in decline in institutional and normative settings. This can be perceived as symptomatic of a broader crisis of the international legal order.
The features of Middle Miocene deposits in the Puna-Eastern Cordillera transition (Valles Calchaquies) indicate that Cenozoic deformation, sedimentation and volcanism follow a complex spatiotemporal relationship. The intense volcanic activity recorded in the eastern Puna border between 14 and 11.5 Ma coincides with the occurrence of one of the most important deformation events of the Neogene tectonic evolution in the region. Studies performed across the Puna-Eastern Cordillera transition show different relationships between volcanic deposits of ca. 13.5-12.1 Ma and the Oligocene-Miocene Angastaco Formation. In this paper we describe the ash-flow tuff deposits which are the first of this type found concordant in the sedimentary fill of Valles Calchaquies. Several analyses performed on these pyroclastic deposits allow a correlation to be made with the Alto de Las Lagunas Ignimbrite (ca. 13.5 Ma) of the Pucarilla-Cerro Tipillas Volcanic Complex located in the Puna. Outcrops of the ca. 13.5 Ma pyroclastic deposits are recognised within the Puna and the Valle Calchaqui. However, in the southern prolongation of the Valle de Hualfin (Tiopampa-Pucarilla depression) that separates the Puna from the Valle Calchaqui at these latitudes, these deposits are partially eroded and buried, and thus their occurrence is recorded only by abundant volcanic clasts included in conglomerates of the Angastaco Formation. The sedimentation of the Angastaco Formation was aborted at ca. 12 Ma in the Tiopampa-Pucarilla depression by the Pucarilla Ignimbrite, which unconformably covers the synorogenic units. On the contrary, in the Valle Calchaqui the sedimentation of the Angastaco Formation continued until the Late Miocene. The different relationships between the Miocene Angastaco Formation and the ignimbrites with ages of ca. 13.5 and ca. 12 Ma reveal that in this short period (-1.5 m.y.) a significant deformation event took place and resulted in marked palaeogeographic changes, as evidenced by stratigraphic-sedimentological and chronological records in the Angastaco Formation. (C) 2017 Elsevier B.V. All rights reserved.
Agrammatic speakers of languages with overt grammatical case show impaired use of the morphological cues to establish theta-role relations in sentences presented in non-canonical word orders. We analysed the effect of word order on the sentence comprehension of aphasic speakers of Basque, an ergative, free word order and head-final (SOV) language. Ergative languages such as Basque establish a one-to-one mapping of the thematic role and the case marker. We collected behavioural and gaze-fixation data while agrammatic speakers performed a picture-matching task with auditorily presented sentences with different word orders. We found that people with aphasia (PWA) had difficulties in assigning theta-roles in Theme-Agent order. This result is in line with processing accounts. Contrary to previous findings, our data do not suggest a systematic delay in the integration of morphological information in the PWA group, but strong reliance on the ergative case morphology and difficulties assigning thematic roles into the determiner phrases.
Dark matter constraints from a joint analysis of dwarf Spheroidal galaxy observations with VERITAS
(2017)
We present constraints on the annihilation cross section of weakly interacting massive particles dark matter based on the joint statistical analysis of four dwarf galaxies with VERITAS. These results are derived from an optimized photon weighting statistical technique that improves on standard imaging atmospheric Cherenkov telescope (IACT) analyses by utilizing the spectral and spatial properties of individual photon events. We report on the results of similar to 230 hours of observations of five dwarf galaxies and the joint statistical analysis of four of the dwarf galaxies. We find no evidence of gamma-ray emission from any individual dwarf nor in the joint analysis. The derived upper limit on the dark matter annihilation cross section from the joint analysis is 1.35 x 10(-23) cm(3) s(-1) at 1 TeV for the bottom quark (b (b) over bar) final state, 2.85 x 10(-24) cm(3) s(-1) at 1 TeV for the tau lepton (tau+tau(-)) final state and 1.32 x 10-25 cm(3) s(-1) at 1 TeV for the gauge boson (gamma gamma) final state.
Imaging atmospheric Cherenkov telescopes (IACTs) are equipped with sensitive photomultiplier tube (PMT) cameras. Exposure to high levels of background illumination degrades the efficiency of and potentially destroys these photo-detectors over time, so IACTs cannot be operated in the same configuration in the presence of bright moonlight as under dark skies. Since September 2012, observations have been carried out with the VERITAS IACTs under bright moonlight (defined as about three times the night-sky-background (NSB) of a dark extragalactic field, typically occurring when Moon illumination > 35%) in two observing modes, firstly by reducing the voltage applied to the PMTs and, secondly, with the addition of ultra-violet (UV) bandpass filters to the cameras. This has allowed observations at up to about 30 times previous NSB levels (around 80% Moon illumination), resulting in 30% more observing time between the two modes over the course of a year. These additional observations have already allowed for the detection of a flare from the 1ES 1727 + 502 and for an observing program targeting a measurement of the cosmic-ray positron fraction. We provide details of these new observing modes and their performance relative to the standard VERITAS observations. (C) 2017 Elsevier B.V. All rights reserved.
We present a search for magnetically broadened gamma-ray emission around active galactic nuclei (AGNs), using VERITAS observations of seven hard-spectrum blazars. A cascade process occurs when multi-TeV gamma-rays from an AGN interact with extragalactic background light (EBL) photons to produce electron-positron pairs, which then interact with cosmic microwave background photons via inverse-Compton scattering to produce gamma-rays. Due to the deflection of the electron- positron pairs, a non-zero intergalactic magnetic field (IGMF) would potentially produce detectable effects on the angular distribution of the cascade emission. In particular, an angular broadening compared to the unscattered emission could occur. Through non-detection of angularly broadened emission from 1ES 1218 vertical bar 304, the source with the largest predicted cascade fraction, we exclude a range of IGMF strengths around 10(-14) G at the 95% confidence level. The extent of the exclusion range varies with the assumptions made about the intrinsic spectrum of 1ES. 1218+304 and the EBL model used in the simulation of the cascade process. All of the sources are used to set limits on the flux due to extended emission.
Despite the myriad of organic donor:acceptor materials, only few systems have emerged in the life of organic solar cells to, exhibit considerable reduced bimolecular recombination, with respect to the random encounter rate given by the Langevin equation. Monte Carlo simulations have revealed that the rate constant of the formation of electron-hole bound states depends on the random encounter of opposite charges and is nearly given by the Langevin equation for the domain sizes relevant to efficient bulk heterojunction systems. Recently, three studies :suggested that charge transfer states dissociating much faster than their decay rate to the ground state, can result in reduced bimolecular recombination by lowering the recombination rate to the ground state as a loss pathway. A separate study identified another loss pathway and suggested that forbidden back electron transfer from triplet charge transfer states to triplet excitons is a key to achieving reduced recombination. Herein we further explain the reduced bimolecular recombination by investigating the limitations of these two proposals. By solving kinetic rate equations for a BHJ system with realistic rates, we show that both of these previously presented conditions must only be held at the same time fora system to exhibit non-Langevin behavior. We demonstrate that suppression of both of the parallel loss channels of singlet and triplet states can be achieved through increasing the dissociation rate of the charge transfer states; a crucial requirement to achieve a high charge carrier extraction efficiency.
The sustainability of agro-bioenergy systems is dependent on many factors, some local or regional in implementation, some others global in nature. This study assessed the effects of often ignored local and regional factors (e.g. alternative agronomic factor options, alternative agricultural production systems, alternative biomass flows, alternative conversion technologies etc. The results from this study suggests that key to enhancing the energy efficiency (and by extension the sustainability) of agro-bioenergy systems is paying attention to local and regional factors such as biomass conversion technology, alternative agronomic factor options, alternative agricultural production systems and available biomass flows.
In light of possible future restrictions on the use of fossil fuel, due to climate change obligations and continuous depletion of global fossil fuel reserves, the search for alternative renewable energy sources is expected to be an issue of great concern for policy stakeholders. This study assessed the feasibility of bioenergy production under relatively low-intensity conservative, eco-agricultural settings (as opposed to those produced under high-intensity, fossil fuel based industrialized agriculture). Estimates of the net energy gain (NEG) and the energy return on energy invested (EROEI) obtained from a life cycle inventory of the energy inputs and outputs involved reveal that the energy efficiency of bioenergy produced in low-intensity eco-agricultural systems could be as much as much as 448.5–488.3 GJ·ha−1 of NEG and an EROEI of 5.4–5.9 for maize ethanol production systems, and as much as 155.0–283.9 GJ·ha−1 of NEG and an EROEI of 14.7–22.4 for maize biogas production systems. This is substantially higher than for industrialized agriculture with a NEG of 2.8–52.5 GJ·ha−1 and an EROEI of 1.2–1.7 for maize ethanol production systems, as well as a NEG of 59.3–188.7 GJ·ha−1 and an EROEI of 2.2–10.2 for maize biogas production systems. Bioenergy produced in low-intensity eco-agricultural systems could therefore be an important source of energy with immense net benefits for local and regional end-users, provided a more efficient use of the co-products is ensured.
Optical control of magnetization using femtosecond laser without applying any external magnetic field offers the advantage of switching magnetic states at ultrashort time scales. Recently, all-optical helicity-dependent switching (AO-HDS) has drawn a significant attention for potential information and data storage device applications. In this work, we employ element and magnetization sensitive photoemission electron microscopy (PEEM) to investigate the role of heating in AO-HDS for thin films of the rare-earth transition-metal alloy TbFe. Spatially resolved measurements in a 3–5 μm sized stationary laser spot demonstrate that AO-HDS is a local phenomenon in the vicinity of thermal demagnetization in a ‘ring’ shaped region. The efficiency of AO-HDS further depends on a local temperature profile around the demagnetized region and thermally activated domain wall motion. We also demonstrate that the thickness of the film determines the preferential switching direction for a particular helicity.
The 1911 Chon-Kemin (Kebin) earthquake culminated c. 30 years of remarkable earthquakes in the northern Tien Shan (Kyrgyzstan and Kazakhstan). Building on prior mapping of the event, we traced its rupture in the field and measured more than 50 offset landforms. Cumulative fault rupture length is >155-195 km along 13 fault patches comprising six sections. The patches are separated by changes of dip magnitude or dip direction, or by 4-10 km-wide stepovers. One <40 km section overlaps and is parallel to the main north-dipping rupture but is 7 km north and dips opposite (south). Both ends of the rupture are along mountain front thrust faults demonstrating late Quaternary activity. We computed the moment from each fault patch using the surface fault traces, dip inferred from the traces, 20 km seismogenic thickness, rigidity of 3.3 x 10(10) N m(-2) and dip slip converted from our observations of the largely reverse sense of motion vertical offsets. The discontinuous patches with c. 3-4 m average slip and peak slip of <14 m yield a seismic moment of 4.6 x 10(20) Nm (M-w 7.78) to 7.4 x 10(20) Nm (M-w 7.91). The majority of moment was released along the inner eastern rupture segments. This geological moment is lower by a factor of 1.5 from that determined from teleseismic data.
Processing grammatical evidentiality and time reference in Turkish heritage and monolingual speakers
(2017)
The aim of our study was to examine the extent to which linguistic approaches to sentence comprehension deficits in aphasia can account for differential impairment patterns in the comprehension of wh-questions in bilingual persons with aphasia (PWA). We investigated the comprehension of subject and object wh-questions in both Turkish, a wh-in-situ language, and German, a wh-fronting language, in two bilingual PWA using a sentence-to-picture matching task. Both PWA showed differential impairment patterns in their two languages. SK, an early bilingual PWA, had particular difficulty comprehending subject which-questions in Turkish but performed normal across all conditions in German. CT, a late bilingual PWA, performed more poorly for object which-questions in German than in all other conditions, whilst in Turkish his accuracy was at chance level across all conditions. We conclude that the observed patterns of selective cross-linguistic impairments cannot solely be attributed either to difficulty with wh-movement or to problems with the integration of discourse-level information. Instead our results suggest that differences between our PWA’s individual bilingualism profiles (e.g. onset of bilingualism, premorbid language dominance) considerably affected the nature and extent of their impairments.
The aim of our study was to examine the extent to which linguistic
approaches to sentence comprehension deficits in aphasia can
account for differential impairment patterns in the comprehension
of wh-questions in bilingual persons with aphasia (PWA). We investi-
gated the comprehension of subject and object wh-questions in both
Turkish, a wh-in-situ language, and German, a wh-fronting language,
in two bilingual PWA using a sentence-to-picture matching task. Both
PWA showed differential impairment patterns in their two languages.
SK, an early bilingual PWA, had particular difficulty comprehending
subject which-questions in Turkish but performed normal across all
conditions in German. CT, a late bilingual PWA, performed more
poorly for object which-questions in German than in all other condi-
tions, whilst in Turkish his accuracy was at chance level across all
conditions. We conclude that the observed patterns of selective
cross-linguistic impairments cannot solely be attributed either to
difficulty with wh-movement or to problems with the integration of
discourse-level information. Instead our results suggest that differ-
ences between our PWA’s individual bilingualism profiles (e.g. onset
of bilingualism, premorbid language dominance) considerably
affected the nature and extent of their impairments.
This study investigates the comprehension of wh-questions in individuals with aphasia (IWA) speaking Turkish, a non-wh-movement language, and German, a wh-movement language. We examined six German-speaking and 11 Turkish-speaking IWA using picture-pointing tasks. Findings from our experiments show that the Turkish IWA responded more accurately to both object who and object which questions than to subject questions, while the German IWA performed better for subject which questions than in all other conditions. Using random forest models, a machine learning technique used in tree-structured classification, on the individual data revealed that both the Turkish and German IWA’s response accuracy is largely predicted by the presence of overt and unambiguous case marking. We discuss our results with regard to different theoretical approaches to the comprehension of wh-questions in aphasia.
This study investigates the comprehension of wh-questions in individuals with aphasia (IWA) speaking Turkish, a non-wh-movement language, and German, a wh-movement language. We examined six German-speaking and 11 Turkish-speaking IWA using picture-pointing tasks. Findings from our experiments show that the Turkish IWA responded more accurately to both object who and object which questions than to subject questions, while the German IWA performed better for subject which questions than in all other conditions. Using random forest models, a machine learning technique used in tree-structured classification, on the individual data revealed that both the Turkish and German IWA’s response accuracy is largely predicted by the presence of overt and unambiguous case marking. We discuss our results with regard to different theoretical approaches to the comprehension of wh-questions in aphasia.
Systemic trafficking and storage of essential metal ions play fundamental roles in living organisms by serving as essential cofactors in various cellular processes. Thereby metal quantification and localization are critical steps in understanding metal homeostasis, and how their dyshomeostasis might contribute to disease etiology and the ensuing pathologies. Furthermore, the amount and distribution of metals in organisms can provide insight into their underlying mechanisms of toxicity and toxicokinetics. While in vivo studies on metal imaging in mammalian experimental animals are complex, time- and resource-consuming, the nematode Caenorhabditis elegans (C. elegans) provides a suitable comparative and complementary model system. Expressing homologous genes to those inherent to mammals, including those that regulate metal homeostasis and transport, C. elegans has become a powerful tool to study metal homeostasis and toxicity. A number of recent technical advances have been made in the development and application of analytical methods to visualize metal ions in C. elegans. Here, we briefly summarize key findings and challenges of the three main techniques and their application to the nematode, namely sensing fluorophores, microbeam synchrotron radiation X-ray fluorescence as well as laser ablation ( LA) coupled to inductively coupled plasma-mass spectrometry (ICP-MS).
Up until recently, signatures of the ultrarelativistic electron loss driven by electromagnetic ion cyclotron (EMIC) waves in the Earth's outer radiation belt have been limited to direct or indirect measurements of electron precipitation or the narrowing of normalized pitch angle distributions in the heart of the belt. In this study, we demonstrate additional observational evidence of ultrarelativistic electron loss that can be driven by resonant interaction with EMIC waves. We analyzed the profiles derived from Van Allen Probe particle data as a function of time and three adiabatic invariants between 9 October and 29 November 2012. New local minimums in the profiles are accompanied by the narrowing of normalized pitch angle distributions and ground‐based detection of EMIC waves. Such a correlation may be indicative of ultrarelativistic electron precipitation into the Earth's atmosphere caused by resonance with EMIC waves.
In our search for new antiplasmodial agents, the CH2Cl2/CH3OH (1:1) extract of the roots of Tephrosia aequilata was investigated, and observed to cause 100% mortality of the chloroquine-sensitive (3D7) strain of Plasmodium falciparum at a 10 mg/mL concentration. From this extract three new chalconoids, E-2,6-dimethoxy-3,4-(2,2-dimethyl)pyranoretrochalcone (1, aequichalcone A), Z-2,6-dimethoxy-3,4-(2,2-dimethyl)pyranoretrochalcone (2, aequichalcone B), 4-ethoxy-3-hydroxypraecansone B (3, aequichalcone C) and a new pterocarpene, 3,4:8,9-dimethylenedioxy-6a,11a-pterocarpene (4), along with seven known compounds were isolated. The purified compounds were characterized by NMR spectroscopic and mass spectrometric analyses. Compound 1 slowly converts into 2 in solution, and thus the latter may have been enriched, or formed, during the extraction and separation process. The isomeric compounds 1 and 2 were both observed in the crude extract. Some of the isolated constituents showed good to moderate antiplasmodial activity against the chloroquine-sensitive (3D7) strain of Plasmodium falciparum.
Kettle holes are small inland waters formed from glacially-created depressions often situated in agricultural landscapes. Due to their high perimeter-to-area ratio facilitating a high aquatic-terrestrial coupling, kettle holes can accumulate high concentrations of organic carbon and nutrients, fueling microbial activities and turnover rates. Thus, they represent hotspots of carbon turnover in the landscape, but their bacterial activities and controlling factors have not been well investigated. Therefore, we aimed to assess the relative importance of various environmental factors on bacterial and biogeochemical processes in the water column of kettle holes and to disentangle their variations. In the water body of ten kettle holes in north-eastern Germany, we measured several physico-chemical and biological parameters such as carbon quantity and quality, as well as bacterial protein production (BP) and community respiration (CR) in spring, early summer and autumn 2014. Particulate organic matter served as an indicator of autochthonous production and represented an important parameter to explain variations in BP and CR. This notion is supported by qualitative absorbance indices of dissolved molecules in water samples and C: N ratios of the sediments, which demonstrate high fractions of autochthonous organic matter (OM) in the studied kettle holes. In contrast, dissolved chemical parameters were less important for bacterial activities although they revealed strong differences throughout the growing season. Pelagic bacterial activities and dynamics might thus be regulated by autochthonous OM in kettle holes implying a control of important biogeochemical processes by internal primary production rather than facilitated exchange with the terrestrial surrounding due to a high perimeter-to-area ratio.
Integral Fourier operators
(2017)
This volume of contributions based on lectures delivered at a school on Fourier Integral Operators
held in Ouagadougou, Burkina Faso, 14–26 September 2015, provides an introduction to Fourier Integral Operators (FIO) for a readership of Master and PhD students as well as any interested layperson. Considering the wide
spectrum of their applications and the richness of the mathematical tools they involve, FIOs lie the cross-road of many a field. This volume offers
the necessary background, whether analytic or geometric, to get acquainted with FIOs, complemented by more advanced material presenting various aspects of active research in that area.
Obesity is a key component of equine metabolic syndrome, which is highly associated with laminitis. Feed restriction and/or exercise are known to alleviate the detrimental effects of insulin resistance in obese ponies. However, little is known about changes in the serum lipid patterns due to weight reduction and its association with disease outcomes. Therefore, the lipid patterns in the serum of 14 mature ponies before and after a 14-week body weight reduction program (BWRP) were investigated by multi-one-dimensional thin-layer chromatography (MOD-TLC). Additionally, sensitivity to insulin (SI), body condition scores (BCS) and cresty neck scores (CNS) were measured. A BWRP resulted in a significant loss of body weight (P < 0.001), which was associated with beneficial decreases in BCS and CNS (both, P < 0.001). Serum lipid compositions revealed significantly increased free fatty acid (FFA), sphingomyelin (SM; both P < 0.001), total cholesterol (C) and cholesterol ester (CE) (both P < 0.01) and triacylglycerol (TG; P < 0.05) densities. Improvement of SI after the BWRP was associated with increases in neutral lipids (C, CE and TG, all P < 0.01), FFA and the phospholipid SM (both, P < 0.001). The results show that a BWRP in obese ponies was effective and associated with changes in the concentrations of neutral lipids and the phospholipid SM, indicating that SM may play a role in insulin signaling pathways and thus in the pathogenesis of insulin resistance and the progression of metabolic syndrome in obese ponies.
High-pressure/low-temperature (HP/LT) chloritoid-bearing micaschists crop out widely in the central part of northern Turkey and represent deep-seated subduction-accretionary complexes. Three peak metamorphic assemblages are identified in the area studied: (1) garnet-chloritoid-glaucophane with pseudomorphs after lawsonite; (2) chloritoid with pseudomorphs after glaucophane; and (3) chloritoid with pseudomorphs after jadeite in addition to phengite, paragonite, quartz, chlorite, rutile, and apatite. The latter is interpreted as transformation of a chloritoid + glaucophane assemblage to chloritoid + jadeite with increasing pressure; PT modeling indicates similar to 17 and 22-25 kbars for the two peak parageneses. The diversity of peak metamorphic assemblages and the PT estimates suggest that basal accretion occurred at different depths within the wedge. The depth of the basal accretion is possibly controlled by the slab-mantle decoupling depth. Stretching and thinning of the lithospheric fore arc induced by the slab rollback possibly caused shallowing of the slab-mantle decoupling depth which limited depth of the basal accretion from 70-80km to similar to 55km within the subduction channel. A slab-mantle coupling depth-controlled basal accretion may also explain the scarcity of eclogite and high-grade blueschist facies metamorphic rocks in active intraoceanic subduction zones. Because the overriding plate is young and hot in intraoceanic subductions, the slab and mantle are coupled at a relatively shallow depth before eclogitization of the oceanic crust. This prevents accretion and exhumation of eclogite along the subduction channel.
Rezensiertes Werk
Theresa Biberauer u. George Walkden (Hgg.): Syntax over Time: Lexical, Morphological, and Information – Structural Interactions - Oxford, Oxford University Press, 2015, 418 S.
Recent philosophical analyses of the epistemic dimension of images in the sciences show a certain trend in acknowledging potential roles of these images beyond their merely decorative or pedagogical functions. We argue, however, that this new debate has yet paid little attention to a special type of pictures, we call ‘visual metaphor’, and its versatile heuristic potential in organizing data, supporting communication, and guiding research, modeling, and theory formation. Based on a case study of Conrad Hal Waddington’s epigenetic landscape images in biology, we develop a descriptive framework applicable to heuristic roles of various visual metaphors in the sciences.
Mantle Flow as a Trigger for Subduction Initiation: A Missing Element of the Wilson Cycle Concept
(2017)
The classical Wilson Cycle concept, describing repeated opening and closing of ocean basins, hypothesizes spontaneous conversion of passive continental margins into subduction zones. This process, however, is impeded by the high strength of passive margins, and it has never occurred in Cenozoic times. Here using thermomechanical models, we show that additional forcing, provided by mantle flow, which is induced by neighboring subduction zones and midmantle slab remnants, can convert a passive margin into a subduction zone. Models suggest that this is a long-term process, thus explaining the lack of Cenozoic examples. We speculate that new subduction zones may form in the next few tens of millions of years along the Argentine passive margin and the U.S. East Coast. Mantle suction force can similarly trigger subduction initiation along large oceanic fracture zones. We propose that new subduction zones will preferentially originate where subduction zones were active in the past, thus explaining the remarkable colocation of subduction zones during at least the last 400 Myr.