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We investigate the physical state of H?i absorbing gas at low redshift (z = 0.25) using a subset of cosmological, hydrodynamic simulations from the OverWhelmingly Large Simulations project, focusing in particular on broad (bHI=40 km s-1) H?i Lya absorbers (BLAs), which are believed to originate in shock-heated gas in the warm-hot intergalactic medium (WHIM). Our fiducial model, which includes radiative cooling by heavy elements and feedback by supernovae and active galactic nuclei, predicts that by z = 0.25 nearly 60?per cent of the gas mass ends up at densities and temperatures characteristic of the WHIM and we find that half of this fraction is due to outflows. The standard H?i observables (distribution of H?i column densities NH?I, distribution of Doppler parameters bHI, bHINH?I correlation) and the BLA line number density predicted by our simulations are in remarkably good agreement with observations. BLAs arise in gas that is hotter, more highly ionized and more enriched than the gas giving rise to typical Lya forest absorbers. The majority of the BLAs arise in warm-hot [log?(T/?K) similar to 5] gas at low (log?? < 1.5) overdensities. On average, thermal broadening accounts for at least 60?per cent of the BLA linewidth, which in turn can be used as a rough indicator of the thermal state of the gas. Detectable BLAs account for only a small fraction of the true baryon content of the WHIM at low redshift. In order to detect the bulk of the mass in this gas phase, a sensitivity at least one order of magnitude better than achieved by current ultraviolet spectrographs is required. We argue that BLAs mostly trace gas that has been shock heated and enriched by outflows and that they therefore provide an important window on a poorly understood feedback process.
We experimentally analyze collective dynamics of a population of 20 electronic Wien-bridge limit-cycle oscillators with a nonlinear phase-shifting unit in the global feedback loop. With an increase in the coupling strength we first observe formation and then destruction of a synchronous cluster, so that the dependence of the order parameter on the coupling strength is not monotonic. After destruction of the cluster the ensemble remains nevertheless coherent, i.e., it exhibits an oscillatory collective mode (mean field). We show that the system is now in a self-organized quasiperiodic state, predicted in Rosenblum and Pikovsky [Phys. Rev. Lett. 98, 064101 (2007)]. In this state, frequencies of all oscillators are smaller than the frequency of the mean field, so that the oscillators are not locked to the mean field they create and their dynamics is quasiperiodic. Without a nonlinear phase-shifting unit, the system exhibits a standard Kuramoto-like transition to a fully synchronous state. We demonstrate a good correspondence between the experiment and previously developed theory. We also propose a simple measure which characterizes the macroscopic incoherence-coherence transition in a finite-size ensemble.
Time-dependent escape of cosmic rays from supernova remnants, and their interaction with dense media
(2012)
Context. Supernova remnants (SNRs) are thought to be the main source of Galactic cosmic rays (CRs) up to the "knee" in CR spectrum. During the evolution of a SNR, the bulk of the CRs are confined inside the SNR shell. The highest-energy particles leave the system continuously, while the remaining adiabatically cooled particles are released when the SNR has expanded sufficiently and decelerated so that the magnetic field at the shock is no longer able to confine them. Particles escaping from the parent system may interact with nearby molecular clouds, producing.-rays in the process via pion decay. The soft gamma-ray spectra observed for a number of SNRs interacting with molecular clouds, however, challenge current theories of non-linear particle acceleration that predict harder spectra.
Aims. We study how the spectrum of escaped particles depends on the time-dependent acceleration history in both Type Ia and core-collapse SNRs, as well as on different assumptions about the diffusion coefficient in the vicinity of the SNR.
Methods. We solve the CR transport equation in a test-particle approach combined with numerical simulations of SNR evolution.
Results. We extend our method for calculating the CR acceleration in SNRs to trace the escaped particles in a large volume around SNRs. We calculate the evolution of the spectra of CRs that have escaped from a SNR into a molecular cloud or dense shell for two diffusion models. We find a strong confinement of CRs in a close region around the SNR, and a strong dilution effect for CRs that were able to propagate out as far as a few SNR radii.
Particle spectra from acceleration at forward and reverse shocks of young Type Ia Supernova Remnants
(2012)
We study cosmic-ray acceleration in young Type Ia Supernova Remnants (SNRs) by means of test-particle diffusive shock acceleration theory and 1-D hydrodynamical simulations of their evolution. In addition to acceleration at the forward shock, we explore the particle acceleration at the reverse shock in the presence of a possible substantial magnetic field, and consequently the impact of this acceleration on the particle spectra in the remnant. We investigate the time evolution of the spectra for various time-dependent profiles of the magnetic field in the shocked region of the remnant. We test a possible influence on particle spectra of the Alfvenic drift of scattering centers in the precursor regions of the shocks. In addition, we study the radiation spectra and morphology in a broad band from radio to gamma-rays. It is demonstrated that the reverse shock contribution to the cosmic-ray particle population of young Type la SNRs may be significant, modifying the spatial distribution of particles and noticeably affecting the volume-integrated particle spectra in young SNRs. In particular spectral structures may arise in test-particle calculations that are often discussed as signatures of non-linear cosmic-ray modification of shocks. Therefore, the spectrum and morphology of emission, and their time evolution, differ from pure forward-shock solutions.
Many agriculture-based economies are increasingly under stress from climate change and socio-economic pressures. The excessive exploitation of natural resources still represents the standard procedure to achieve socio-economic development. In the area of the Moulouya river basin, Morocco, natural water availability represents a key resource for all economic activities. Agriculture represents the most important sector, and frequently occurring water deficits are aggravated by climate change. On the basis of historical trends taken from CRU TS 2.1, this paper analyses the impact of climate change on the per capita water availability under inclusion of population trends. The Climatic Water Balance (CWB) shows a significant decrease for the winter period, causing adverse effects for the main agricultural season. Further, moisture losses due to increasing evapotranspiration rates indicate problems for the annual water budget and groundwater recharge. The per capita blue water availability falls below a minimum threshold of 500 m(3) per year, denoting a high regional vulnerability to increasing water scarcity assuming a no-response scenario. Regional development focusing on the water-intense sectors of agriculture and tourism appears to be at risk. Institutional capacities and policies need to address the problem, and the prompt implementation of innovative water production and efficiency measures is recommended.
The globally threatened Aquatic Warbler Acrocephalus paludicola is a Palearctic-African long-distance migrant that undergoes a complete moult while wintering in Africa. Little is known about the timing of moult and the birds' mobility during moulting periods. We conducted the first study on the moult of Aquatic Warblers, in the Djoudj area of Senegal, West Africa. Wing moult scores from 36 to 90 and raggedness scores from 0 to 25 were recorded in December and January. No moulting Aquatic Warblers were caught after January. Body-feather moult was observed during and shortly after wing moult until January. We conclude that Aquatic Warblers follow the typical sequence of passerine moult, with remige moult starting in October or November. To find out how moult affects their mobility, we measured the net distance that Aquatic Warblers equipped with radio transmitters travelled in 15-min intervals. In our small sample of eight birds, the mean path length was 34 m, and there was no obvious difference between the path lengths in moulting and non-moulting individuals. We conclude that, possibly, moult does not affect the mobility and flight ability of Aquatic Warblers in general. Further research is needed to locate other wintering grounds, e.g. in the Inner Niger Delta, and reproduce our study in other populations.
The well-known cationic surfactant hexadecyltrimethylammonium bromide (CTAB) was used as a model carrier to study drug-carrier interactions with fluorescence probes (5-hexadecanoylaminofluorescein (HAF) and 2,10-bis-(3-aminopropyloxy)dibenzo[aj]perylene-8,16-dione (NIR 628) by applying ensemble as well as single molecule fluorescence techniques. The impact of the probes on the micelle parameters (critical micelle concentration, average aggregation number, hydrodynamic radius) was investigated under physiological conditions. In the presence of additional electrolytes, such as buffer, the critical micelle concentration decreased by a factor of about 10. In contrast, no influence of the probes on the critical micelle concentration and on average aggregation number was observed. The results show that HAF does not affect the characteristics of CTAB micelles. Analyzing fluorescence correlation spectroscopy data and time-resolved anisotropy decays in terms of the "two-step" in combination with the "wobbling-in-cone" model, it was proven that HAF and NIR 628 are differently associated with the micelles. Based on ensemble and single molecule fluorescence experiments, intra- and intermicellar energy transfer process between the two dyes were probed and characterized.
The sensing potential of CuO nanoparticles synthesized via. precipitation from a water/ionic liquid precursor (ILP) mixture was investigated. The particles have a moderate surface area of 66 m(2)/g after synthesis, which decreases upon thermal treatment to below 5 m(2)/g. Transmission electron microscopy confirms crystal growth upon annealing, likely due to sintering effects. The as-synthesized particles can be used for ethanol sensing. The respective sensors show fast response and recovery times of below 10 s and responses greater than 2.3 at 100 ppm of ethanol at 200 degrees C, which is higher than any CuO-based ethanol sensor described so far.
Background: Triblock copolymers from hydrophilic oligo(ethylene glycol) segment A and oligo(propylene glycol) segment B, providing an ABA structure (OEG-OPG-OEG triblock), are known to be biocompatible and are used as self-solidifying gels in drug depots. A complete removal of these depots would be helpful in cases of undesired side effects of a drug, but this remains a challenge as they liquefy below their transition temperature. Therefore we describe the synthesis of covalently cross-linked hydrogel networks.
Method: Triblock copolymer-based hydrogels were created by irradiating aqueous solutions of the corresponding macro-dimethacrylates with UV light. The degree of swelling, swelling kinetics, mechanical properties and morphology of the networks were investigated.
Results: Depending on precursor concentration, equilibrium degree of swelling of the films ranged between 500% and 880% and was reached in 1 hour. In addition, values for storage and loss moduli of the hydrogel networks were in the 100 Pa to 10 kPa range.
Conclusion: Although OEG-OPG-OEG triblocks are known for their micellization, which could hamper polymer network formation, reactive OEG-OPG-OEG triblock oligomers could be successfully polymerized into hydrogel networks. The degree of swelling of these hydrogels depends on their molecular weight and on the oligomer concentration used for hydrogel preparation. In combination with the temperature sensitivity of the ABA triblock copolymers, it is assumed that such hydrogels might be beneficial for future medical applications -e.g., removable drug release systems.
Neue Forschungen zur japanischen Militärgeschichte des 16. bis zur Mitte des 19. Jahrhunderts
(2012)
1. Einleitung: Aspekte der Militärgeschicht 2. Militärgeschichtsforschung zur Sengoku- und Oda-Toyotomi-Zeit (1) Zu den Kriegen in der Sengoku- und Oda-Toyotomi-Zeit (1467/77 bis 1600/03) (2) Feuerwaffen (3) Burgen und Schlösser (4) Militärorganisation und Kriegsdisziplin (5) Proviantlieferung, Rüstungsgüter und Handelsverkehr (6) Krieg und Gesellschaft 3. Militärgeschichtsforschung zur Edo-Zeit (1600/03–1868) (1) Kriegsgeschichtliche Untersuchungen (2) Die Schlosspolitik als Herrschaftsmittel (3) Mobilisierung der Truppen (4) Militär und Gesellschaft (5) Waffenbesitz und -gebrauch (6) Die Einführung der abendländischen Kriegstechnik und die Küstenverteidigung (7) Bauernsoldaten am Ende der Edo-Zeit (8) Gedächtnis des Krieges, Gefallenenkult und Ideologie 4. Schlussbetrachtung: Krieg und Frieden, Ausbau der Staatsgewalt
To identify genetic variants associated with head circumference in infancy, we performed a meta-analysis of seven genome-wide association studies (GWAS) (N = 10,768 individuals of European ancestry enrolled in pregnancy and/or birth cohorts) and followed up three lead signals in six replication studies (combined N = 19,089). rs7980687 on chromosome 12q24 (P = 8.1 x 10(-9)) and rs1042725 on chromosome 12q15 (P = 2.8 x 10(-10)) were robustly associated with head circumference in infancy. Although these loci have previously been associated with adult height(1), their effects on infant head circumference were largely independent of height (P = 3.8 x 10(-7) for rs7980687 and P = 1.3 x 10(-7) for rs1042725 after adjustment for infant height). A third signal, rs11655470 on chromosome 17q21, showed suggestive evidence of association with head circumference (P = 3.9 x 10(-6)). SNPs correlated to the 17q21 signal have shown genome-wide association with adult intracranial volume(2), Parkinson's disease and other neurodegenerative diseases(3-5), indicating that a common genetic variant in this region might link early brain growth with neurological disease in later life.
Im Juli des Jahres 1841 kommt es zu einem Treffen zwischen zwei Männern, das zunächst belanglos erscheint, sich aber Jahre später als wichtige historische Begebenheit herausstellen wird. In seinem Pariser Büro empfängt der 71jährige Naturforscher Alexander von Humboldt den jungen Preußen Ludwig Leichhardt. Der angehende Naturwissenschaftler erhofft sich Zuspruch und Empfehlung des berühmten Alexander von Humboldts. Die Unterredung ist kurz und verläuft für Leichhardt ergebnislos. Es wird das einzige Treffen der beiden Naturwissenschaftler bleiben. Aus heutiger Sicht unverständlich, da Ludwig Leichhardt und Alexander von Humboldt mehr verband, als ihre Leidenschaft für die Naturwissenschaften. Viel zu wenig ist sich bis jetzt den biographischen Analogien und den vergleichbaren geographischen Leistungen der beiden Preußen gewidmet worden.
The majority of cases of community-acquired pneumonia are caused by Streptococcus pneumoniae and most studies on pneumococcal host interaction are based on cell culture or animal experiments. Thus, little is known about infections in human lung tissue.
Cyclooxygenase-2 and its metabolites play an important regulatory role in lung inflammation. Therefore, we established a pneumococcal infection model on human lung tissue demonstrating mitogen-activated protein kinase (MAPK)-dependent induction of cyclooxygenase-2 and its related metabolites.
In addition to alveolar macrophages and the vascular endothelium, cyclooxygenase-2 was upregulated in alveolar type II but not type I epithelial cells, which was confirmed in lungs of patients suffering from acute pneumonia. Moreover, we demonstrated the expression profile of all four E prostanoid receptors at the mRNA level and showed functionality of the E prostanoid(4) receptor by cyclic adenosine monophosphate production. Additionally, in comparison to previous studies, cyclooxygenase-2/prostaglandin E-2 related pro- and anti-inflammatory mediator regulation was partly confirmed in human lung tissue after pneumococcal infection.
Overall, cell type-specific and MAPK-dependent cyclooxygenase-2 expression and prostaglandin E-2 formation in human lung tissue may play an important role in the early phase of pneumococcal infections.
In Central and NW Europe, the transition from the Permian to the Triassic (i.e., the Zechstein-Buntsandstein boundary interval) is developed mainly in red bed facies. This continental sedimentary succession is marked by relatively high sedimentation rates providing a high temporal resolution favorable for magnetic polarity stratigraphy. Here, we present a Zechstein to Lower Buntsandstein magnetostratigraphy obtained from the c. 100 m thick Everdingen-1 core from the Netherlands. Seven magnetozones (EV1n to EV4n) and five submagnetozones (EV1n.1r to EV3r.1n) have been delineated. The Everdingen-1 magnetostratigraphy has been integrated into the well-established high-resolution Zechstein-Buntsandstein stratigraphic framework, and verifies the geomagnetic polarity record from Central Germany. This confirms the hypothesis of nearly synchronous base-level cycles within the interior of the Central European Basin. These cycles are related to solar-induced similar to 100 ka eccentricity cycles. The most distinctive feature of the Everdingen-1 magnetostratigraphy is a transition from a thin reverse to a thick dominantly normal magnetic polarity interval. This reversal predates both the terrestrial mass extinction, which is indicated by a palynofloral turnover and a major sediment provenance change at the base of the Buntsandstein, and the marine Permian-Triassic Boundary (PTB). The PTB is located within the lowermost Buntsandstein and is approximated by the last occurrence of the conchostracan Falsisca postera and a negative excursion in the carbon isotope record. According to the Buntsandstein cyclostratigraphy, the R/N reversal predates the marine end-Permian extinction event by about 0.1 Ma and the marine biostratigraphic PTB by about 0.2 Ma. The thick normal magnetozone is estimated to have lasted c. 700 ka, and roughly coincides with the main phase of Siberian Trap volcanism.
Cross-dressing took on new political meanings in Germany's Weimar Republic, with the emergence of organizations and periodicals aimed at promoting the interests of self-identified "transvestites." This new sexological category, developed by Magnus Hirschfeld in 1910, formed the basis for a shared sense of identity and belonging among individuals who identified as members of the "opposite" sex. Drawing on the experiences of the homosexual emancipation movement and discourses of bourgeois respectability, middle-class transvestites came together to demand legal and social recognition, including acknowledgement of "transsexual" desires. Their efforts represent a critical but forgotten moment in the history of transgender political activism.
Context. The true mass-loss rates from massive stars are important for many branches of astrophysics. For the correct modeling of the resonance lines, which are among the key diagnostics of stellar mass-loss, the stellar wind clumping has been found to be very important. To incorporate clumping into a radiative transfer calculation, three-dimensional (3D) models are required. Various properties of the clumps may have a strong impact on the resonance line formation and, therefore, on the determination of empirical mass-loss rates.
Aims. We incorporate the 3D nature of the stellar wind clumping into radiative transfer calculations and investigate how different model parameters influence the resonance line formation.
Methods. We develop a full 3D Monte Carlo radiative transfer code for inhomogeneous expanding stellar winds. The number density of clumps follows the mass conservation. For the first time, we use realistic 3D models that describe the dense as well as the tenuous wind components to model the formation of resonance lines in a clumped stellar wind. At the same time, we account for non-monotonic velocity fields.
Results. The 3D density and velocity wind inhomogeneities show that there is a very strong impact on the resonance line formation. The different parameters describing the clumping and the velocity field results in different line strengths and profiles. We present a set of representative models for various sets of model parameters and investigate how the resonance lines are affected. Our 3D models show that the line opacity is lower for a larger clump separation and shallower velocity gradients within the clumps.
Conclusions. Our model demonstrates that to obtain empirically correct mass-loss rates from the UV resonance lines, the wind clumping and its 3D nature must be taken into account.
Background: The goal was to study lipid profiles (TG, TC, LDL, HDL), effects on serum leptin, and fat tissue adiponectin, and resistin as well as body weight effects of Shan He Jian Fei Granules (SHJFG) in rats on a high fat diet.
Methods: Rats were randomly divided into five groups: normal control group fed with normal fat diet, rats on high fat diet receiving low dosage, middle dosage, high dosage of Shan He Jian Fei Granules (SHJFG) as well as a high fat diet group receiving placebo. Rats were treated for 8 weeks. Body weight and naso-anal length of each rat were recorded and Lee's index was calculated. Serum TG, TC, LDL, HDL and leptin concentrations were analyzed. The gene expressions of adiponectin and resistin in adipose tissues were tested by RT-PCR.
Results: Compared to the high-fat diet group, body weights, Lee's indexes, weight of fat tissues and serum TG, TC, LDL and leptin of SHJFG groups significantly decreased (p<0.05), whereas mRNA expressions of adiponectin and resistin of SHJFG groups significantly increased (p<0.05).
Conclusions: SHJFG could significantly lower body weight and serum TG, TC, and LDL of obese rats. The effects of SHJFG in lowering leptin synthesis and raising mRNA expression of adiponectin and resistin in fat tissues may act as part of the mechanisms in lowering body weight of obese rats. Further studies are needed to demonstrate whether SHJFG may also reduce overall cardiovascular morbidity and mortality like other lipid lowering drugs.
Reliability tests for wavelength-stabilized compact diode laser systems emitting at 671 nm are presented. The devices were mounted on microoptical benches with the dimensions of 13 mm x 4 mm. Reflecting Bragg gratings were used for wavelength stabilization and emission width narrowing. The reliability tests were performed at 25 degrees C and at an output power up to 10 mW per micrometer stripe width of the gain medium. Reliable operation could be demonstrated over a test time up to 14 500 h at an output power up to 1.0 W. Environmental tests using random vibrations with acceleration up to 29 g were performed without deterioration of the devices.
Analyzing pre-climax positions of everyday affect-laden telling activities, this paper shows that particular facial expressions, such as raised eyebrows with an open mouth or jaw-dropping, are the devices which are preferably deployed by story recipients as a minimal uptake to display affiliation, especially in the case of "scary" stories.
During the course of conversational storytelling, it is structurally necessary that recipients warrant the tellers speakership. At the same time, a particular affective display-not only in response to what has been said but also to what comes at the climax-appears to become relevant. Immediately prior to the climax, when the teller employs elaborate multimodal cues, the recipient's display of an "anticipatory affect" is made relevant. A particular type of affect signals the anticipation of what kind of climax is approaching. The present paper explores how story recipients accomplish this two-fold task, namely to display alignment with the speaker's role allocation and listenership on the one hand and affiliation on the other. The study argues that a minimal uptake is called for, requiring only a minimal slot in the flow of storytelling and facial expressions that are most likely to fit this slot.
Coincident with the intensification of Northern Hemisphere Glaciation (WIG) around 2.73 million years (Ma) ago, sediment cores from both the open subarctic North Pacific and the Antarctic indicate a rapid decline in diatom opal accumulation flux to the seabed, representing one of the most abrupt and dramatic changes in the marine sediment record associated with the development of Pleistocene glacial cycles. In the North Pacific, bulk sediment nitrogen isotope data and alkenone-derived sea surface temperature (SST) estimates suggest that the productivity decline was driven by reduced exchange between surface and deep water, due to weaker wind-driven upwelling and/or a strengthening of the halocline (i.e. "stratification"). In this study of the 2.73 Ma transition at Ocean Drilling Program (ODP) Site 882 in the western subarctic North Pacific, diatom-bound nitrogen isotopes (delta N-15(db)), alkenone mass accumulation rate, and alkenone- and archaeal tetraether-based SST reconstructions support the stratification hypothesis, indicating perennially lower export production, generally higher nitrate consumption, and greater inter-seasonal variation in SST after the 2.73 Ma transition. In addition, the delta N-15(db) of large and small size fractions of Coscinodiscus spp. suggest that these diatoms grew mostly during the spring bloom during the late Pliocene, switching to their current fall-to-winter growth period at the 2.73 Ma transition; this view is consistent with their decline in dominance and provides further evidence for increased stratification (reduced vertical exchange) in the North Pacific after 2.73 Ma. The delta N-15(db) data indicate that, over the similar to 100 kyr period after the 2.73 Ma transition studied here, nitrate consumption did not reach late Pleistocene ice age levels and that nitrate consumption in post-2.73 Ma warm stages was similar to that before the transition, even though productivity was greatly reduced. We tentatively attribute this to relatively weak dust-borne iron inputs in the early post-2.73 Ma period.
The present paper investigates potential fiscal and distributional effects which emerge due to four reform scenarios on the German income tax rate. The analysis is based on a static simulation model for the German tax system using income tax micro-data. The data shows that changing the present progressive tax system to a flat-tax, which was proposed by the FDP in 2010, could reduce the tax revenue by 15 billion Euro. Such a tax regime would increase the unequal distribution and polarisation of net incomes. The IW Koln suggested an alternative tax rate in 2008. This regime would increase unequal distribution and polarisation of disposable incomes to a greater extent than the FDP-tax rate. An implementation of this income tax scale would go along with losses in tax revenue of 18.8 billion Euro. Likewise, the implementation of a 2009 SPD tax rate proposal would reduce tax revenue by 14.8 billion Euro. Although this regime would reduce unequal distribution, the effect on the polarization of disposable incomes is not definitely predictable. In contrast to all the other scenarios, the realisation of the recent SPD tax rate proposal from 2011 could enlarge tax revenue by 4.7 billion Euro. This tax regime would reduce unequal distribution and polarisation of disposable incomes even more than the present tax system.
There is an observational correlation between astrophysical shocks and nonthermal particle distributions extending to high energies. As a first step toward investigating the possible feedback of these particles on the shock at the microscopic level, we perform particle-in-cell (PIC) simulations of a simplified environment consisting of uniform, interpenetrating plasmas, both with and without an additional population of cosmic rays. We vary the relative density of the counterstreaming plasmas, the strength of a homogeneous parallel magnetic field, and the energy density in cosmic rays. We compare the early development of the unstable spectrum for selected configurations without cosmic rays to the growth rates predicted from linear theory, for assurance that the system is well represented by the PIC technique. Within the parameter space explored, we do not detect an unambiguous signature of any cosmic-ray-induced effects on the microscopic instabilities that govern the formation of a shock. We demonstrate that an overly coarse distribution of energetic particles can artificially alter the statistical noise that produces the perturbative seeds of instabilities, and that such effects can be mitigated by increasing the density of computational particles.
A temporary seismic network composed of 11 stations was installed in the city of Potenza (Southern Italy) to record local and regional seismicity within the context of a national project funded by the Italian Department of Civil Protection (DPC). Some stations were moved after a certain time in order to increase the number of measurement points, leading to a total of 14 sites within the city by the end of the experiment. Recordings from 26 local earthquakes (M-l 2.2-3.8 ) were analyzed to compute the site responses at the 14 sites by applying both reference and non-reference site techniques. Furthermore, the Spectral Intensity (SI) for each local earthquake, as well as their ratios with respect to the values obtained at a reference site, were also calculated. In addition, a field survey of 233 single station noise measurements within the city was carried out to increase the information available at localities different from the 14 monitoring sites. By using the results of the correlation analysis between the horizontal-to-vertical spectral ratios computed from noise recordings (NHV) at the 14 selected sites and those derived by the single station noise measurements within the town as a proxy, the spectral intensity correction factors for site amplification obtained from earthquake analysis were extended to the entire city area. This procedure allowed us to provide a microzonation map of the urban area that can be directly used when calculating risk scenarios for civil defence purposes. The amplification factors estimated following this approach show values increasing along the main valley toward east where the detrital and alluvial complexes reach their maximum thickness.
This Letter describes four new 4-trimethylammonio-2,2,6,6-tetramethylpiperidine-1-yloxyls bearing camphorsulfonate, triflate, tosylate, or lactate as counter ions. These spin probes were made by anion metathesis of 4-trimethylammonio-2,2,6,6-tetramethylpiperidine-1-yloxyl iodide using the corresponding silver salts. The latter is made by the alkylation of 4-amino-2,2,6,6-tetramethylpiperidine-1-yloxyl. Furthermore, the Letter gives an improved synthetic way to 4-sulfonamido-2,2,6,6-tetramethylpiperidine-1-yloxyl using chlorosulfuric acid trimethylsilylester and 4-amino-2,2,6,6-tetramethylpiperidine-1-yloxyl. All the spin probes are highly interesting for the investigation of ionic liquids.
Inspired by the results from the PISA study and based on previous intervention programs, the reading competence training LEKOLEMO (Program for Fostering Reading Literacy and Reading Motivation) for 7th-grade students was developed. The training differs from existing programs in two aspects: (1) It comprises tasks pertaining to the PISA reading dimensions retrieving information, text-related interpretation, and reflection and evaluation, and (2) explicitly aims at fostering reading motivation. The present study examined the revised version of LEKOLEMO in a sample of 235 seventh graders. The results confirmed the effectiveness of LEKOLEMO and showed significant effects of medium size on reading competence at the follow-up test. However, effects on intrinsic reading motivation and on self-concept of reading were small and unstable.
Die Freiheit des Geldes
(2012)
Hidden diversity in diatoms of Kenyan Lake Naivasha a genetic approach detects temporal variation
(2012)
This study provides insights into the morphological and genetic diversity in diatoms occurring in core sediments from tropical lakes in Kenya. We developed a genetic survey technique specific for diatoms utilizing a short region (7667 bp) of the ribulose-1,5-bisphosphate carboxylase/oxygenase large subunit (rbcL) gene as genetic barcode. Our analyses (i) validated the use of rbcL as a barcoding marker for diatoms, applied to sediment samples, (ii) showed a significant correlation between the results obtained by morphological and molecular data and (iii) indicated temporal variation in diatom assemblages on the inter- and intra-specific level. Diatom assemblages from a short core from Lake Naivasha show a drastic shift over the last 200 years, as littoral species (e.g. Navicula) are replaced by more planktonic ones (e.g. Aulacoseira). Within that same period, we detected periodic changes in the respective frequencies of distinct haplotype groups of Navicula, which coincide with wet and dry periods of Lake Naivasha between 1820 and 1938 AD. Our genetic analyses on historical lake sediments revealed inter- and intra-specific variation in diatoms, which is partially hidden behind single morphotypes. The occurrence of particular genetic lineages is probably correlated with environmental factors.
Syntheses of thiazolidine-fused heterocycles via exo-mode cyclizations of vinylogous N-acyliminium ions incorporating heteroatom-based nucleophiles have been examined and discussed. The formation of (5,6)-membered systems was feasible with all nucleophiles tried (O, S and N), while the closing of the five-membered ring was restricted to O- and S-nucleophiles. The closure of a four-membered ring failed. Instead, the bicyclic (5,6)-membered acetal derivative and the tricyclic system with an eight-membered central ring were obtained from the substrates containing O and S nucleophilic moieties, respectively. The reaction outcome and stereochemistry are rationalized using quantum chemical calculations at B3LYP/6-31G(d) level. The exclusive cis-stereoselectivity in the formation of (5,6)- and (5,5)-membered systems results from thermodynamic control, whereas the formation of the eight-membered ring was kinetically controlled.
Der Beitrag zeichnet die Beziehungen zwischen dem Dichterpaar Wolfgang Hilbig und Natascha Wodin nach, die auch aufgrund ihrer gemeinsamen östlichen Wurzeln zueinanderfanden. Der Vergleich der romana "Das provisorium" und "Nachtgeschwister" thematisiert beider Beziehungen. Dies wird im Beitrag referiert und mit der besonderen Perspektive der Wechselseitigkeit reflektiert.
We explore the photophysics of P(NDI2OD-T2), a high-mobility and air-stable n-type donor/acceptor polymer. Detailed steady-state UV-vis and photoluminescence (PL) measurements on solutions of P(NDI2OD-T2) reveal distinct signatures of aggregation. By performing quantum chemical calculations, we can assign these spectral features to unaggregated and stacked polymer chains. NMR measurements independently confirm the aggregation phenomena of P(NDI2OD-T2) in solution. The detailed analysis of the optical spectra shows that aggregation is a two-step process with different types of aggregates, which we confirm by time-dependent PL measurements. Analytical ultracentrifugation measurements suggest that aggregation takes place within the single polymer chain upon coiling. By transferring these results to thin P(NDI2OD-T2) films, we can conclude that film formation is mainly governed by the chain collapse, leading in general to a high aggregate content of similar to 45%. This process also inhibits the formation of amorphous and disordered P(NDI2OD-T2) films.
Regionale Sprachgemeinschaften und Sprachdynamik : zwischen Kodifizierung und Schreibtradition
(2012)
The meaning of linguistic connectives has often been characterized in terms of their position in a bipartite (semantic, pragmatic) or a tripartite (content, epistemic, speech act) structure of domains, depending on what kinds of entities are being connected (largely: propositions or speech acts). This paper argues that a more fine-grained analysis can be achieved by directing some more attention to the characterization of the entities being related. We propose an inventory of categories of illocutionary status for labelling the spans that are being connected. On this basis, the distinction between the content and the epistemic domain, in particular, can be made more explicit. Focusing on the group of causal connectives in German, we conducted a corpus annotation study from which we derived distinct pragmatic 'usage profiles' of the most frequent causal connectives. Finally, we offer some suggestions on the role of illocutions in relation-based accounts of discourse structure.
Annotating linguistic data has become a major field of interest, both for supplying the necessary data for machine learning approaches to NLP applications, and as a research issue in its own right. This comprises issues of technical formats, tools, and methodologies of annotation. We provide a brief overview of these notions and then introduce the papers assembled in this special issue.
Cell-free protein synthesis is of increasing interest for the rapid and high-throughput synthesis of many proteins, in particular also antibody fragments. In this study, we present a novel strategy for the production of single chain antibody fragments (scFv) in a eukaryotic in vitro translation system. This strategy comprises the cell-free expression, isolation and label-free interaction analysis of a model antibody fragment synthesized in two differently prepared insect cell lysates. These lysates contain translocationally active microsomal structures derived from the endoplasmic reticulum (ER), allowing for posttranslational modifications of cell-free synthesized proteins. Both types of these insect cell lysates enable the synthesis and translocation of scFv into ER-derived vesicles. However, only the one that has a specifically adapted redox potential yields functional active antibody fragments. We have developed a new methodology for the isolation of functional target proteins based on the translocation of cell-free produced scFv into microsomal structures and subsequent collection of protein-enriched vesicles. Antibody fragments that have been released from these vesicles are shown to be well suited for label-free binding studies. Altogether, these results show the potential of insect cell lysates for the production, purification and selection of antibody fragments in an easy-to-handle and time-saving manner.
In the framework of the Dead Sea Integrated Research project (DESIRE), 59 seismological stations were deployed in the region of the Dead Sea Basin. Twenty of these stations recorded data of sufficiently high quality between May and September 2007 to be used for ambient seismic noise analysis. Empirical Green's functions are extracted from cross-correlations of long term recordings. These functions are dominated by Rayleigh waves, whose group velocities can be measured in the frequency range from 0.1 to 0.5 Hz. Analysis of positive and negative correlation lags of the Green's functions makes it possible to identify the direction of the source of the incoming energy. Signals with frequencies higher than 0.2 Hz originate from the Mediterranean Sea, while low frequencies arrive from the direction of the Red Sea. Travel times of the extracted Rayleigh waves were measured between station pairs for different frequencies, and tomographically inverted to provide independent velocity models. Four such 2D models were computed for a set of frequencies, all corresponding to different sampling depths, and thus together giving an indication of the velocity variations in 3D extending to a depth of 10 km. The results show low velocities in the Dead Sea Basin, consistent with previous studies suggesting up to 8 km of recent sedimentary infill in the Basin. The complex structure of the western margin of the Basin is also observed, with sedimentary infill present to depths not exceeding 5 km west of the southern part of the Dead Sea. The high velocities associated with the Lisan salt diapir are also observed down to a depth of similar to 5 km. The reliability of the results is confirmed by checkerboard recovery tests.
Movement kinematics affect action prediction comparing human to non-human point-light actions
(2012)
The influence of movement kinematics on the accuracy of predicting the time course of another individual's actions was studied. A human point-light shape was animated with human movement (natural condition) and with artificial movement that was more uniform regarding velocity profiles and trajectories (artificial condition). During brief occlusions, the participants predicted the actions in order to judge after occlusion whether the actions were continued coherently in time or shifted to an earlier or later frame. Error rates and reaction times were increased in the artificial compared to the natural condition. The findings suggest a perceptual advantage for movement with a human velocity profile, corresponding to the notion of a close interaction between observed and executed movement. The results are discussed in the framework of the simulation account and alternative interpretations are provided on the basis of correlations between the velocity profiles of natural and artificial movements with prediction performance.