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The nature of the periplastidial pathway of starch biosynthesis was investigated with the model cryptophyte Guillardia theta. The storage polysaccharide granules were shown to be composed of both amylose and amylopectin fractions with a chain length distribution and crystalline organization very similar to those of starch from green algae and land plants. Most starch granules displayed a shape consistent with biosynthesis occurring around the pyrenoid through the rhodoplast membranes. A protein with significant similarity to the amylose-synthesizing granule-bound starch syntbase 1 from green plants was found as the major polypeptide bound to the polysaccharide matrix. N-terminal sequencing of the mature protein proved that the precursor protein carries a nonfunctional transit peptide in its bipartite topogenic signal sequence which is cleaved without yielding transport of the enzyme across the two inner plastid membranes. The enzyme was shown to display similar affinities for ADP and UDP-glucose, while the V-max measured with UDP-glucose was twofold higher. The granule-bound starch synthase from Guillardia theta was demonstrated to be responsible for the synthesis of long glucan chains and therefore to be the functional equivalent of the amylose- synthesizing enzyme of green plants. Preliminary characterization of the starch pathway suggests that Guillardia theta utilizes a UDP-glucose-based pathway to synthesize starch
Formation of epithermal Sn-Ag-(Zn) vein-type mineralization at the Pirquitas deposit, NW Argentina
(2018)
The Pirquitas Sn-Ag-(Zn) deposit in northwestern Argentina is thought to be an analogue to the Miocene polymetallic epithermal Sn-Ag deposits of the southern Bolivian Tin Belt, but little is known in detail about the origin and evolution of ore-forming fluids at Pirquitas. This paper reports on a microthermometric study of fluid inclusions in quartz, sphalerite, Ag-Sn sulfides, and Ag-rich sulfosalts using transmitted near infrared and visible light, combined with noble gas isotope analyses of fluids released from mineral separates. The study focused on the vein-hosted mineralization, which formed during two major mineralization events, whereby the first event I comprises two stages (I-1 and I-2). All studied minerals exclusively contain aqueous two-phase inclusions, indicating that the ore-forming fluids did not undergo two-phase phase separation (boiling). Salinity of fluid inclusions in I-1 quartz that precipitated along with pyrite and pyrrhotite ranges between 0 and 7.5 wt% NaCl equiv. and homogenization temperatures (Th) are between 233 and 370 degrees C. Stage I-2 is characterized by abundant Sn-Ag-Pb-Zn-sulfides and a variety of Ag-rich sulfosalts. Fluid inclusions in stage I-2 Ag-Sn sulfides have salinities up to 10.6 wt% NaCl equiv. and Th between 213 and 274 degrees C. The deposition of stage I-2 ore is likely related to a new pulse of saline magmatic fluids to the hydrothermal system. The mineralization event II deposited the richest Ag ores at Pirquitas. Colloform sphalerite and pyrargyrite deposited during event II contain two-phase aqueous fluid inclusions with homogenization temperatures between 190 and 252 degrees C and salinities between 0.9 and 4.3 wt% NaCl equiv. Noble gas concentrations and isotopic compositions of ore-hosted fluid inclusions were determined from crushing hand-picked ore minerals from both mineralization events. With one exception, all samples yielded He-3/He-4 ratios between 1.9 and 4.1 Ra, which is within the range of published data from the volcanic arc and somewhat higher than typical values of meteoric water-derived hot-springs in the region. This demonstrates a significant contribution of magmatic fluids to the Pirquitas mineralization although no intrusive rocks are exposed in the mine region. Taking the noble gas evidence for a magmatic fluid source, we interpret the trends of decreasing Th and salinity values in fluid inclusions from events I and II to represent waning of the magmatic-hydrothermal system and/or increased admixing of meteoric water to the magmatic fluids.
The Central Andes host large reserves of base and precious metals. The region represented, in 2017, an important part of the worldwide mining activity. Three principal types of deposits have been identified and studied: 1) porphyry type deposits extending from central Chile and Argentina to Bolivia, and Northern Peru, 2) iron oxide-copper-gold (IOCG) deposits, extending from central Peru to central Chile, and 3) epithermal tin polymetallic deposits extending from Southern Peru to Northern Argentina, which compose a large part of the deposits of the Bolivian Tin Belt (BTB). Deposits in the BTB can be divided into two major types: (1) tin-tungsten-zinc pluton-related polymetallic deposits, and (2) tin-silver-lead-zinc epithermal polymetallic vein deposits.
Mina Pirquitas is a tin-silver-lead-zinc epithermal polymetallic vein deposit, located in north-west Argentina, that used to be one of the most important tin-silver producing mine of the country. It was interpreted to be part of the BTB and it shares similar mineral associations with southern pluton related BTB epithermal deposits. Two major mineralization events related to three pulses of magmatic fluids mixed with meteoric water have been identified. The first event can be divided in two stages: 1) stage I-1 with quartz, pyrite, and cassiterite precipitating from fluids between 233 and 370 °C and salinity between 0 and 7.5 wt%, corresponding to a first pulse of fluids, and 2) stage I-2 with sphalerite and tin-silver-lead-antimony sulfosalts precipitating from fluids between 213 and 274 °C with salinity up to 10.6 wt%, corresponding to a new pulse of magmatic fluids in the hydrothermal system. The mineralization event II deposited the richest silver ores at Pirquitas. Event II fluids temperatures and salinities range between 190 and 252 °C and between 0.9 and 4.3 wt% respectively. This corresponds to the waning supply of magmatic fluids. Noble gas isotopic compositions and concentrations in ore-hosted fluid inclusions demonstrate a significant contribution of magmatic fluids to the Pirquitas mineralization although no intrusive rocks are exposed in the mine area.
Lead and sulfur isotopic measurements on ore minerals show that Pirquitas shares a similar signature with southern pluton related polymetallic deposits in the BTB. Furthermore, the major part of the sulfur isotopic values of sulfide and sulfosalt minerals from Pirquitas ranges in the field for sulfur derived from igneous rocks. This suggests that the main contribution of sulfur to the hydrothermal system at Pirquitas is likely to be magma-derived. The precise age of the deposit is still unknown but the results of wolframite dating of 2.9 ± 9.1 Ma and local structural observations suggest that the late mineralization event is younger than 12 Ma.
The transfer of Microcystis aeruginosa from freshwater to estuaries has been described worldwide and salinity is reported as the main factor controlling the expansion of M. aeruginosa to coastal environments. Analyzing the expression levels of targeted genes and employing both targeted and non-targeted metabolomic approaches, this study investigated the effect of a sudden salt increase on the physiological and metabolic responses of two toxic M. aeruginosa strains separately isolated from fresh and brackish waters, respectively, PCC 7820 and 7806. Supported by differences in gene expressions and metabolic profiles, salt tolerance was found to be strain specific. An increase in salinity decreased the growth of M. aeruginosa with a lesser impact on the brackish strain. The production of intracellular microcystin variants in response to salt stress correlated well to the growth rate for both strains. Furthermore, the release of microcystins into the surrounding medium only occurred at the highest salinity treatment when cell lysis occurred. This study suggests that the physiological responses of M. aeruginosa involve the accumulation of common metabolites but that the intraspecific salt tolerance is based on the accumulation of specific metabolites. While one of these was determined to be sucrose, many others remain to be identified. Taken together, these results provide evidence that M. aeruginosa is relatively salt tolerant in the mesohaline zone and microcystin (MC) release only occurs when the capacity of the cells to deal with salt increase is exceeded.
The transfer of Microcystis aeruginosa from freshwater to estuaries has been described worldwide and salinity is reported as the main factor controlling the expansion of M. aeruginosa to coastal environments. Analyzing the expression levels of targeted genes and employing both targeted and non-targeted metabolomic approaches, this study investigated the effect of a sudden salt increase on the physiological and metabolic responses of two toxic M. aeruginosa strains separately isolated from fresh and brackish waters, respectively, PCC 7820 and 7806. Supported by differences in gene expressions and metabolic profiles, salt tolerance was found to be strain specific. An increase in salinity decreased the growth of M. aeruginosa with a lesser impact on the brackish strain. The production of intracellular microcystin variants in response to salt stress correlated well to the growth rate for both strains. Furthermore, the release of microcystins into the surrounding medium only occurred at the highest salinity treatment when cell lysis occurred. This study suggests that the physiological responses of M. aeruginosa involve the accumulation of common metabolites but that the intraspecific salt tolerance is based on the accumulation of specific metabolites. While one of these was determined to be sucrose, many others remain to be identified. Taken together, these results provide evidence that M. aeruginosa is relatively salt tolerant in the mesohaline zone and microcystin (MC) release only occurs when the capacity of the cells to deal with salt increase is exceeded.
The valediction of Moses
(2021)
Wilhelm Moses Shapira's infamous Deuteronomy fragments have long been deemed forgeries, with Shapira himself serving as the obvious suspect. I provide new evidence that Shapira did not forge the fragments and was himself convinced of their authenticity. Indeed, the evidence for forgery is illusory. In a companion monograph, I show that the Shapira fragments are not only authentic ancient artifacts but are unprecedented in their significance: They preserve a pre-canonical antecedent of the Book of Deuteronomy.
VS30, slope, H800 and f0
(2017)
The aim of this paper is to investigate the ability of various site-condition proxies (SCPs) to reduce ground-motion aleatory variability and evaluate how SCPs capture nonlinearity site effects. The SCPs used here are time-averaged shear-wave velocity in the top 30 m (VS30), the topographical slope (slope), the fundamental resonance frequency (f0) and the depth beyond which Vs exceeds 800 m/s (H800). We considered first the performance of each SCP taken alone and then the combined performance of the 6 SCP pairs [VS30–f0], [VS30–H800], [f0–slope], [H800–slope], [VS30–slope] and [f0–H800]. This analysis is performed using a neural network approach including a random effect applied on a KiK-net subset for derivation of ground-motion prediction equations setting the relationship between various ground-motion parameters such as peak ground acceleration, peak ground velocity and pseudo-spectral acceleration PSA (T), and Mw, RJB, focal depth and SCPs. While the choice of SCP is found to have almost no impact on the median groundmotion prediction, it does impact the level of aleatory uncertainty. VS30 is found to perform the best of single proxies
at short periods (T < 0.6 s), while f0 and H800 perform better at longer periods; considering SCP pairs leads to significant improvements, with particular emphasis on [VS30–H800] and [f0–slope] pairs. The results also indicate significant nonlinearity on the site terms for soft sites and that the most relevant loading parameter for characterising nonlinear site response is the “stiff” spectral ordinate at the considered period.
The aim of this paper is to investigate the ability of various site-condition proxies (SCPs) to reduce ground-motion aleatory variability and evaluate how SCPs capture nonlinearity site effects. The SCPs used here are time-averaged shear-wave velocity in the top 30 m (V-S30), the topographical slope (slope), the fundamental resonance frequency (f(0)) and the depth beyond which V-s exceeds 800 m/s (H800). We considered first the performance of each SCP taken alone and then the combined performance of the 6 SCP pairs [V-S30-f(0)], [V-S30-H-800], [f(0)-slope], [H-800-slope], [V-S30-slope] and [f(0)-H-800]. This analysis is performed using a neural network approach including a random effect applied on a KiK-net subset for derivation of ground-motion prediction equations setting the relationship between various ground-motion parameters such as peak ground acceleration, peak ground velocity and pseudo-spectral acceleration PSA (T), and Mw, RJB, focal depth and SCPs. While the choice of SCP is found to have almost no impact on the median groundmotion prediction, it does impact the level of aleatory uncertainty. VS30 is found to perform the best of single proxies at short periods (T < 0.6 s), while f(0) and H-800 perform better at longer periods; considering SCP pairs leads to significant improvements, with particular emphasis on [V-S30-H-800] and [f(0)-slope] pairs. The results also indicate significant nonlinearity on the site terms for soft sites and that the most relevant loading parameter for characterising nonlinear site response is the "stiff" spectral ordinate at the considered period.
We compare the ability of various site-condition proxies (SCPs) to reduce the aleatory variability of ground motion prediction equations (GMPEs). Three SCPs (measured V-S30, inferred V-S30, local topographic slope) and two accelerometric databases (RESORCE and NGA-West2) are considered. An artificial neural network (ANN) approach including a random-effect procedure is used to derive GMPEs setting the relationship between peak ground acceleration (PGA), peak ground velocity (PGV), pseudo-spectral acceleration [PSA(T)], and explanatory variables (M-w, R-JB, and V-S30 or Slope). The analysis is performed using both discrete site classes and continuous proxy values. All "non-measured" SCPs exhibit a rather poor performance in reducing aleatory variability, compared to the better performance of measured V-S30. A new, fully data-driven GMPE based on the NGA-West2 is then derived, with an aleatory variability value depending on the quality of the SCP. It proves very consistent with previous GMPEs built on the same data set. Measuring V-S30 allows for benefit from an aleatory variability reduction up to 15%.
Nonlinear force-free field (NLFFF) models are thought to be viable tools for investigating the structure, dynamics, and evolution of the coronae of solar active regions. In a series of NLFFF modeling studies, we have found that NLFFF models are successful in application to analytic test cases, and relatively successful when applied to numerically constructed Sun-like test cases, but they are less successful in application to real solar data. Different NLFFF models have been found to have markedly different field line configurations and to provide widely varying estimates of the magnetic free energy in the coronal volume, when applied to solar data. NLFFF models require consistent, force-free vector magnetic boundary data. However, vector magnetogram observations sampling the photosphere, which is dynamic and contains significant Lorentz and buoyancy forces, do not satisfy this requirement, thus creating several major problems for force-free coronal modeling efforts. In this paper, we discuss NLFFF modeling of NOAA Active Region 10953 using Hinode/SOT-SP, Hinode/XRT, STEREO/SECCHI-EUVI, and SOHO/MDI observations, and in the process illustrate three such issues we judge to be critical to the success of NLFFF modeling: (1) vector magnetic field data covering larger areas are needed so that more electric currents associated with the full active regions of interest are measured, (2) the modeling algorithms need a way to accommodate the various uncertainties in the boundary data, and (3) a more realistic physical model is needed to approximate the photosphere-to-corona interface in order to better transform the forced photospheric magnetograms into adequate approximations of nearly force-free fields at the base of the corona. We make recommendations for future modeling efforts to overcome these as yet unsolved problems.
Although without providing a systematical comparison, it has become clear that the sects or party-factions of Japan’s New Left movement are by no means merely copies of their counterparts in the West. On the other hand their conduct may not be judged as to be a unique Japanese phenomenon. What they embody is, on the whole, a complex symbiosis of universal and particularly Japanese features, which can be observed in the fields of social behavior, organizational structure, and group dynamics. The particularity of the New Left factions is mostly revealed through the higher intensity of specific features rather than through pecularities found only in Japan.
Following the extinction of dinosaurs, the great adaptive radiation of mammals occurred, giving rise to an astonishing ecological and phenotypic diversity of mammalian species. Even closely related species often inhabit vastly different habitats, where they encounter diverse environmental challenges and are exposed to different evolutionary pressures. As a response, mammals evolved various adaptive phenotypes over time, such as morphological, physiological and behavioural ones. Mammalian genomes vary in their content and structure and this variation represents the molecular mechanism for the long-term evolution of phenotypic variation. However, understanding this molecular basis of adaptive phenotypic variation is usually not straightforward.
The recent development of sequencing technologies and bioinformatics tools has enabled a better insight into mammalian genomes. Through these advances, it was acknowledged that mammalian genomes differ more, both within and between species, as a consequence of structural variation compared to single-nucleotide differences. Structural variant types investigated in this thesis - such as deletion, duplication, inversion and insertion, represent a change in the structure of the genome, impacting the size, copy number, orientation and content of DNA sequences. Unlike short variants, structural variants can span multiple genes. They can alter gene dosage, and cause notable gene expression differences and subsequently phenotypic differences. Thus, they can lead to a more dramatic effect on the fitness (reproductive success) of individuals, local adaptation of populations and speciation.
In this thesis, I investigated and evaluated the potential functional effect of structural variations on the genomes of mustelid species. To detect the genomic regions associated with phenotypic variation I assembled the first reference genome of the tayra (Eira barbara) relying on linked-read sequencing technology to achieve a high level of genome completeness important for reliable structural variant discovery. I then set up a bioinformatics pipeline to conduct a comparative genomic analysis and explore variation between mustelid species living in different environments. I found numerous genes associated with species-specific phenotypes related to diet, body condition and reproduction among others, to be impacted by structural variants.
Furthermore, I investigated the effects of artificial selection on structural variants in mice selected for high fertility, increased body mass and high endurance. Through selective breeding of each mouse line, the desired phenotypes have spread within these populations, while maintaining structural variants specific to each line. In comparison to the control line, the litter size has doubled in the fertility lines, individuals in the high body mass lines have become considerably larger, and mice selected for treadmill performance covered substantially more distance. Structural variants were found in higher numbers in these trait-selected lines than in the control line when compared to the mouse reference genome. Moreover, we have found twice as many structural variants spanning protein-coding genes (specific to each line) in trait-selected lines. Several of these variants affect genes associated with selected phenotypic traits. These results imply that structural variation does indeed contribute to the evolution of the selected phenotypes and is heritable.
Finally, I suggest a set of critical metrics of genomic data that should be considered for a stringent structural variation analysis as comparative genomic studies strongly rely on the contiguity and completeness of genome assemblies. Because most of the available data used to represent reference genomes of mammalian species is generated using short-read sequencing technologies, we may have incomplete knowledge of genomic features. Therefore, a cautious structural variation analysis is required to minimize the effect of technical constraints.
The impact of structural variants on the adaptive evolution of mammalian genomes is slowly gaining more focus but it is still incorporated in only a small number of population studies. In my thesis, I advocate the inclusion of structural variants in studies of genomic diversity for a more comprehensive insight into genomic variation within and between species, and its effect on adaptive evolution.
We establish in this paper the existence of weak solutions of infinite-dimensional shift invariant stochastic differential equations driven by a Brownian term. The drift function is very general, in the sense that it is supposed to be neither small or continuous, nor Markov. On the initial law we only assume that it admits a finite specific entropy. Our result strongly improves the previous ones obtained for free dynamics with a small perturbative drift. The originality of our method leads in the use of the specific entropy as a tightness tool and on a description of such stochastic differential equation as solution of a variational problem on the path space.
We analyse different Gibbsian properties of interactive Brownian diffusions X indexed by the lattice $Z^{d} : X = (X_{i}(t), i ∈ Z^{d}, t ∈ [0, T], 0 < T < +∞)$. In a first part, these processes are characterized as Gibbs states on path spaces of the form $C([0, T],R)Z^{d}$. In a second part, we study the Gibbsian character on $R^{Z}^{d}$ of $v^{t}$, the law at time t of the infinite-dimensional diffusion X(t), when the initial law $v = v^{0}$ is Gibbsian.
We establish in this paper the existence of weak solutions of infinite-dimensional shift invariant stochastic differential equations driven by a Brownian term. The drift function is very general, in the sense that it is supposed to be neither bounded or continuous, nor Markov. On the initial law we only assume that it admits a finite specific entropy and a finite second moment.
The originality of our method leads in the use of the specific entropy as a tightness tool and in the description of such infinite-dimensional stochastic process as solution of a variational problem on the path space. Our result clearly improves previous ones obtained for free dynamics with bounded drift.
In this paper, using an algorithm based on the retrospective rejection sampling scheme introduced in [A. Beskos, O. Papaspiliopoulos, and G. O. Roberts,Methodol. Comput. Appl. Probab., 10 (2008), pp. 85-104] and [P. Etore and M. Martinez, ESAIM Probab.Stat., 18 (2014), pp. 686-702], we propose an exact simulation of a Brownian di ff usion whose drift admits several jumps. We treat explicitly and extensively the case of two jumps, providing numerical simulations. Our main contribution is to manage the technical di ffi culty due to the presence of t w o jumps thanks to a new explicit expression of the transition density of the skew Brownian motion with two semipermeable barriers and a constant drift.
Using an algorithm based on a retrospective rejection sampling scheme, we propose an exact simulation of a Brownian diffusion whose drift admits several jumps. We treat explicitly and extensively the case of two jumps, providing numerical simulations. Our main contribution is to manage the technical difficulty due to the presence of two jumps thanks to a new explicit expression of the transition density of the skew Brownian motion with two semipermeable barriers and a constant drift.
The Widom-Rowlinson model (or the Area-interaction model) is a Gibbs point process in R-d with the formal Hamiltonian defined as the volume of Ux epsilon omega B1(x), where. is a locally finite configuration of points and B-1(x) denotes the unit closed ball centred at x. The model is also tuned by two other parameters: the activity z > 0 related to the intensity of the process and the inverse temperature beta >= 0 related to the strength of the interaction. In the present paper we investigate the phase transition of the model in the point of view of percolation theory and the liquid-gas transition. First, considering the graph connecting points with distance smaller than 2r > 0, we show that for any beta >= 0, there exists 0 <(similar to a)(zc) (beta, r) < +infinity such that an exponential decay of connectivity at distance n occurs in the subcritical phase (i.e. z <(similar to a)(zc) (beta, r)) and a linear lower bound of the connection at infinity holds in the supercritical case (i.e. z >(similar to a)(zc) (beta, r)). These results are in the spirit of recent works using the theory of randomised tree algorithms (Probab. Theory Related Fields 173 (2019) 479-490, Ann. of Math. 189 (2019) 75-99, Duminil-Copin, Raoufi and Tassion (2018)). Secondly we study a standard liquid-gas phase transition related to the uniqueness/non-uniqueness of Gibbs states depending on the parameters z, beta. Old results (Phys. Rev. Lett. 27 (1971) 1040-1041, J. Chem. Phys. 52 (1970) 1670-1684) claim that a non-uniqueness regime occurs for z = beta large enough and it is conjectured that the uniqueness should hold outside such an half line ( z = beta >= beta(c) > 0). We solve partially this conjecture in any dimension by showing that for beta large enough the non-uniqueness holds if and only if z = beta. We show also that this critical value z = beta corresponds to the percolation threshold (similar to a)(zc) (beta, r) = beta for beta large enough, providing a straight connection between these two notions of phase transition.
The CH2Cl2/MeOH (1: 1) extract of the stem bark of Millettia oblata ssp. teitensis showed antiplasmodial activity (IC50 = 10-12 mu g/mL) against the chloroquine-sensitive (D6) and chloroquine-resistant (W2) strains of Plasmodium falciparum. Chromatographic separation of the extract led to the isolation of a new isoflavone, 4'-prenyloxyderrone (1), together with known isoflavones (8-O-methylretusin, durmillone, maximaisoflavone B, maximaisoflavone H and maximaisoflavone J), a rotenoid (tephrosin) and a triterpene (lupeol). Similar investigation of Millettia leucantha resulted in the identification of the isoflavones afrormosin and wistin, and the flavone chrysin. The identification of these compounds was based on their spectroscopic data. Five of the isoflavones isolated from these plants as well as 11 previously reported compounds from Millettia dura were tested and showed good to moderate antiplasmodial activities (IC50 = 13-53 mu M), with the new compound, 4'-prenyloxyderrone, being the most active (IC50 = 13-15 mu M).
Transmission of measles virus (MV) from dendritic to airway epithelial cells is considered as crucial to viral spread late in infection. Therefore, pathways and effectors governing this process are promising targets for intervention. To identify these, we established a 3D respiratory tract model where MV transmission by infected dendritic cells (DCs) relied on the presence of nectin-4 on H358 lung epithelial cells. Access to recipient cells is an important prerequisite for transmission, and we therefore analyzed migration of MV-exposed DC cultures within the model. Surprisingly, enhanced motility toward the epithelial layer was observed for MV-infected DCs as compared to their uninfected siblings. This occurred independently of factors released from H358 cells indicating that MV infection triggered cytoskeletal remodeling associated with DC polarization enforced velocity. Accordingly, the latter was also observed for MV-infected DCs in collagen matrices and was particularly sensitive to ROCK inhibition indicating infected DCs preferentially employed the amoeboid migration mode. This was also implicated by loss of podosomes and reduced filopodial activity both of which were retained in MV-exposed uninfected DCs. Evidently, sphingosine kinase (SphK) and sphingosine-1-phosphate (S1P) as produced in response to virus-infection in DCs contributed to enhanced velocity because this was abrogated upon inhibition of sphingosine kinase activity. These findings indicate that MV infection promotes a push-and-squeeze fast amoeboid migration mode via the SphK/S1P system characterized by loss of filopodia and podosome dissolution. Consequently, this enables rapid trafficking of virus toward epithelial cells during viral exit.
Rhodococcus fascians is a Gram-positive phytopathogen that induces shooty hyperplasia on its hosts through the secretion of cytokinins. Global transcriptomics using microarrays combined with profiling of primary metabolites on infected Arabidopsis (Arabidopsis thaliana) plants revealed that this actinomycete modulated pathways to convert its host into a niche. The transcript data demonstrated that R. fascians leaves a very characteristic mark on Arabidopsis with a pronounced cytokinin response illustrated by the activation of cytokinin perception, signal transduction, and homeostasis. The microarray data further suggested active suppression of an oxidative burst during the R. fascians pathology, and comparison with publicly available transcript data sets implied a central role for auxin in the prevention of plant defense activation. Gene Ontology categorization of the differentially expressed genes hinted at a significant impact of infection on the primary metabolism of the host, which was confirmed by subsequent metabolite profiling. The much higher levels of sugars and amino acids in infected plants are presumably accessed by the bacteria as carbon and nitrogen sources to support epiphytic and endophytic colonization. Hexoses, accumulating from a significantly increased invertase activity, possibly inhibited the expression of photosynthesis genes and photosynthetic activity in infected leaves. Altogether, these changes are indicative of sink development in symptomatic tissues. The metabolomics data furthermore point to the possible occurrence of secondary signaling during the interaction, which might contribute to symptom development. These data are placed in the context of regulation of bacterial virulence gene expression, suppression of defense, infection phenotype, and niche establishment.
El Aleph
(2017)
Der argentinische Schriftsteller Jorge Luis Borges (1899-1986) gilt als ein Literat, der bereits in seinen Werken der 30er und 40er Jahre des 20. Jahrhunderts Strukturen geschaffen hat, die später die Postmoderne prägen sollten. Foucault hat sich auf ihn berufen. Borges Erzählungen sind insbesondere von intertextuellen Bezugnahmen und sich in Paradoxien verstrickende Narrative durchzogen. Die Folge ist ein dezentrierter sowie dialogisierender Text, der keine eindeutige Aussage hervorbringt, sondern in einer vielstimmigen und unabgeschlossenen Textauslegung zur Wirkung kommt.
Die vorliegende Studie stellt zur Diskussion, ob ein wesentlicher Grund für Borges’ innovatives, die literarische Postmoderne prägendes Textkonzept darin gesehen werden kann, dass sich der argentinische Schriftsteller nachweislich mit jüdischer Schriftkultur auseinandergesetzt hat. Geht man davon aus, dass die in jüdischer Tradition kultivierte mehrschichtige Textdeutung zugleich einen permanenten, unendlichen Rezeptionsprozess zur Folge hat wird deutlich, dass diese Tradition nicht nur kompatibel zu Borges’ Literatur ist, sondern auch zahlreiche Reflexionen in der modernen Literatur und Literaturforschung angeregt hat.
The Dansgaard-Oeschger oscillations and Heinrich events described in North Atlantic sediments and Greenland ice are expressed in the climate of the tropics, for example, as documented in Arabian Sea sediments. Given the strength of this teleconnection, we seek to reconstruct its range of environmental impacts. We present geochemical and sedimentological data from core SO130-289KL from the Indus submarine slope spanning the last similar to 80 kyr. Elemental and grain size analyses consistently indicate that interstadials are characterized by an increased contribution of fluvial suspension from the Indus River. In contrast, stadials are characterized by an increased contribution of aeolian dust from the Arabian Peninsula. Decadal-scale shifts at climate transitions, such as onsets of interstadials, were coeval with changes in productivity-related proxies. Heinrich events stand out as especially dry and dusty events, indicating a dramatically weakened Indian summer monsoon, potentially increased winter monsoon circulation, and increased aridity on the Arabian Peninsula. This finding is consistent with other paleoclimate evidence for continental aridity in the northern tropics during these events. Our results strengthen the evidence that circum-North Atlantic temperature variations translate to hydrological shifts in the tropics, with major impacts on regional environmental conditions such as rainfall, river discharge, aeolian dust transport, and ocean margin anoxia.
During the last glacial period, the North Atlantic region experienced pronounced, millennial-scale alternations between cold, stadial conditions and milder interstadial conditions-commonly referred to as Dansgaard-Oeschger oscillations-as well as periods of massive iceberg discharge known as Heinrich events(1). Changes in Northern Hemisphere temperature, as recorded in Greenland(2-4), are thought to have affected the location of the Atlantic intertropical convergence zone(5,6) and the strength of the Indian summer monsoon(7,8). Here we use high-resolution records of sediment colour-a measure of terrigenous versus biogenic content-from the Cariaco Basin off the coast of Venezuela and the Arabian Sea to assess teleconnections with the North Atlantic climate system during the last glacial period. The Cariaco record indicates that the intertropical convergence zone migrated seasonally over the site during mild stadial conditions, but was permanently displaced south of the basin during peak stadials and Heinrich events. In the Arabian Sea, we find evidence of a weak Indian summer monsoon during the stadial events. The tropical records show a more variable response to North Atlantic cooling than the Greenland temperature records. We therefore suggest that Greenland climate is especially sensitive to variations in the North Atlantic system-in particular sea-ice extent-whereas the intertropical convergence zone and Indian monsoon system respond primarily to variations in mean Northern Hemisphere temperature.
Uno de los misterios más persistentes en América ha sido dilucidar el origen de los pueblos vernáculos y de sus edificios. Resolver ese misterio ha sido objetivo de numerosos viajeros. Entre 1832 y 1836, siguiendo la estela de viajeros como Alejandro de Humboldt, un supuesto barón checo, Frédéric de Waldeck, consigue vender al gobierno mexicano una empresa exploratoria por las ruinas mayas de Palenque y Uxmal. De esta expedición deja testimonio en numerosos diarios que permanecen inéditos hasta la fecha, y en el libro Voyage pittoresque et archéologique dans la Province d’ Yucatán (1838). En estos escritos ensaya algunas explicaciones sobre el origen de los mayas y, en sus disquisiciones y supuestos, hace continuas referencias al trabajo de Humboldt. En un artículo previo vimos cómo Waldeck asimila el origen de los mayas a uno de los grandes misterios bíblicos de raíz histórica como es el de las tribus perdidas de Israel. En este trabajo presentamos su segunda gran hipótesis: aquella que vincula a Yucatán con la India a través de un modo de interpretar y representar la realidad americana que tiene en el orientalismo europeo su episteme definitiva.
Genisa-Blätter IV
(2023)
Auch wenn Genisot – jüdische Ablagen nicht mehr verwendeter Bücher und Kultgegenstände – in der bisherigen historischen Forschung selten beachtet werden, sind sie als Quellen aus originär jüdischer Hand von hoher Bedeutung und können unser Verständnis der Umsetzung von Ritualen im Kontext der lokalen Gemeinde vertiefen.
Der Schwerpunkt der ‚Genisa-Blätter IV‘ liegt auf Fragen nach jüdisch-rituellen Praktiken und ihrer Bedeutung, ihren Objekten und Akteuren. Acht wissenschaftliche und ein essayistischer Beitrag nähern sich diesen Themen über konkrete Funde aus Genisot mitteleuropäischer jüdischer Gemeinden, von religiösen Texten wie dem Fragment einer Torarolle und einem Minhagim-Buch über Personaldokumente bis hin zu Musiknoten und Kleidungsstücken.
Einleitung
(2023)
Genisa-Blätter III
(2020)
Ursprünglich sollten die „Genisa-Blätter III“ ein europäisches Projekt werden. Veröffentlicht werden sollten Quellen aus Genisot, die im vormals deutschsprachigen Raum gehoben wurden. Das Vorhaben scheiterte. Nunmehr sind im Band sieben Beiträge versammelt, in denen kenntnisreich Funde aus den Ablagen in Alsenz, Altenschönbach, Memmelsdorf, Reckendorf und Veitshöchheim besprochen werden. Der achte Aufsatz knüpft am internationalen Vorhaben an: Im Mittelpunkt des Artikels stehen drei Genisafunde aus Tschechien, genauer gesagt aus den beiden ostböhmischen Ortschaften Luže und Rychnov nad Kněžnou. Alle acht Beiträge gemeinsam verdeutlichen die inhaltliche Spannbreite von Genisot, die sich die Forschung zunutze machen kann: Sie reicht von Aspekten der Wirtschaft und des Rechts, über die Religion bis hin zum alltäglichen Leben und bietet jeweils eigene Geschichten im Spannungsfeld des möglichen Scheiterns.
Genisa-Blätter II
(2017)
In den acht Beiträgen der „Genisa-Blätter II“ werden Funde aus verschiedenen fränkischen Genisot vorgestellt. Sie wurden im Rahmen eines interdisziplinären Workshops im Genisaprojekt Veitshöchheim von Nachwuchswissenschaftlerinnen und -wissenschaftlern aus ganz Deutschland bearbeitet. Die edierten Quellen sowie deren Einordnung durch die Autorinnen und Autoren geben vielfältige Einblicke in die Komplexität des historischen Judentums in Franken. Der Schwerpunkt dieser Ausgabe liegt auf Text- und Textilfunden aus dem Bereich der Religion.
Geographical turn
(2010)
Editorial
(2011)
Inhalt: Editorial (Deutsch) Editorial (Englisch)
Hirsch, L., Vom Schtetl in den Hörsaal, jüdische Frauen und Kulttransfer; Berlin, Metropol, 2010
(2012)
Bundistinnen
(2009)
Pri ha-Pardes (Früchte des Obstgartens) ist eine Reihe der Vereinigung für Jüdische Studien e.V., welche in Verbindung mit dem Zentrum für Jüdische Studien der Universität Potsdam publiziert wird. Pri ha-Pardes möchte kleineren wissenschaftlichen Studien, Forschungen am Rande der großen Disziplinen und exzellenten Masterarbeiten eine Publikationsplattform bieten. Im fünften Band der Reihe Pri ha-Pardes skizziert Rebekka Denz die Geschichte von Frauen im Allgemeinen Jüdischen Arbeiterbund („Bund“) seit seiner Gründung 1897 bis zum Jahr 1939. Durch das Prisma der gewählten Hauptquelle ─ die Frauenbiographien der „Doires Bundistn“, einer jiddischsprachigen Biographiensammlung verfasst von Mitgliedern des „Bund“ ─ werden das Mitwirken und die Bedeutung von Frauen in dieser sozialistischen, jiddischistischen Bewegung Ost(mittel)europas dargestellt. Zudem wird ein erster Versuch unternommen, diesen Teil der bundischen Parteigeschichtsschreibung hinsichtlich ihrer (Re-) Konstruktionsprinzipien zu lesen. Die Arbeit gliedert sich dabei analog zum bundischen Selbstverständnis und der geographischen Verschiebung seines Hauptwirkungsfeldes in zwei Teile: Frauen im „Russischen Bund“ (1897-1917) und Frauen im „Polnischen Bund“ (1918-1939). Die Auswirkungen der unterschiedlichen historischen Kontexte auf lebensweltliche Aspekte, Tätigkeiten in Bewegung und Partei sowie Tendenzen der Lebensgestaltung der Bundistinnen werden anhand von drei Vergleichskapiteln aufgezeigt; weitere Einzelkapitel behandeln zeitspezifische Aspekte. Die Instabilität der Lebensverhältnisse für die Mitglieder im illegalen „Russischen Bund“ bzw. die größere Stabilität in der Zeit des „Bund“ in Polen als legale Partei bilden wichtige, bislang vernachlässigte Faktoren bei der Betrachtung der weiblichen Lebensmuster.
Der „Froyenvinkl“
(2008)
Inhalt: 1. Der „Froyenvinkl“ der „Naye Folkstsaytung“ 2. Die Themenfelder des „Froyenvinkl“ 2.1 Die Berichterstattung über die „Yidishe Arbeter Froy“ (YAF) im „Froyenvinkl“ 2.2 Die Berichterstattung über die (Inter-)Nationalen Frauenbewegungen im „Froyenvinkl“ 2.3 Beiträge von Leserinnen im „Froyenvinkl“ 2.4 Die Diskussionen im „Froyenvinkl“ 2.5 Die Serien im „Froyenvinkl“ Schlussbemerkungen
Rezensiertes Werk:
Anne-Katrin Henkel / Thomas Rahe (Hrsg.): Publizistik in jüdischen Displaced-Persons-Camps. Charakteristika, Medien und bibliothekarische Überlieferung, Zeitschrift für Bibliothekswesen und Bibliographie. Sonderbände, Bd. 112, Frankfurt am Main: Vittorio Klostermann Verlag 2014. 194 S.
Inhalt: BEITRÄGE Catherine Denys Die Renaissance der Militärgeschichte der frühen Neuzeit in Frankreich. Eine historiographische Bilanz der Jahre 1945-2005 Tadashi Suzuki „Befreiung vom Tabu“: Die japanische Forschung zur europäischen Militärgeschichte seit 1945 PROJEKTE Markus von Salisch Die kursächsische Armee und der Siebenjährige Krieg BERICHTE Linda Waack und Rosa Costa Gewalt und Geschlecht. 12. Fachtagung des Arbeitskreises Geschlechtergeschichte der Frühen Neuzeit (2.-4. 11. 2006, Stuttgart-Hohenheim) Katrin Bentz, Nicole Bütow und Thomas Kupka 1806: Jena, Auerstedt und die Kapitulation von Magdeburg. Schande oder Chance? (13.-15. Oktober 2006, Magdeburg) REZENSIONEN Alexander Kästner Stefan Kroll: Soldaten im 18. Jahrhundert zwischen Friedensalltag und Kriegserfahrung. Lebenswelten und Kultur in der kursächsischen Armee, Paderborn u. a. 2006. Max Plassmann Olaf Jessen: Preußens Napoleon? Ernst von Rüchel (1754-1823). Krieg im Lichte der Vernunft, Paderborn 2006 Ulrike Ludwig Cecilia Nubola, Andreas Würgler (Hrsg.), Bittschriften und Gravamina. Politik, Verwaltung und Justiz in Europa (14.-18. Jahrhundert), Berlin 2005 ANKÜNDIGUNGEN Military Studies - Masterstudiengang Militärgeschichte – Militärsoziologie
Pitch Angle Scattering of Sub-MeV Relativistic Electrons by Electromagnetic Ion Cyclotron Waves
(2019)
Electromagnetic ion cyclotron (EMIC) waves have long been considered to be a significant loss mechanism for relativistic electrons. This has most often been attributed to resonant interactions with the highest amplitude waves. But recent observations have suggested that the dominant energy of electrons precipitated to the atmosphere may often be relatively low, less than 1 MeV, whereas the minimum resonant energy of the highest amplitude waves is often greater than 2 MeV. Here we use relativistic electron test particle simulations in the wavefields of a hybrid code simulation of EMIC waves in dipole geometry in order to show that significant pitch angle scattering can occur due to interaction with low-amplitude short-wavelength EMIC waves. In the case we examined, these waves are in the H band (at frequencies above the He+ gyrofrequency), even though the highest amplitude waves were in the He band frequency range (below the He+ gyrofrequency). We also present wave power distributions for 29 EMIC simulations in straight magnetic field line geometry that show that the high wave number portion of the spectrum is in every case mostly due to the H band waves. Though He band waves are often associated with relativistic electron precipitation, it is possible that the He band waves do not directly scatter the sub-megaelectron volts (sub-MeV) electrons, but that the presence of He band waves is associated with high plasma density which lowers the minimum resonant energy so that these electrons can more easily resonate with the H band waves.
L'exil comme patrie
(2017)
Nutrition bioassays in which polyunsaturated fatty acids (PUFA)-deficient diets were supplemented with free long-chain PUFA (>= C20) consistently revealed positive effects on somatic growth and fecundity of Daphnia. However, free PUFA are hardly available in natural diets. In general, PUFA are bound to other lipids, especially to phospholipids and triglycerides. Here, we evaluate the potential of free and phospholipid-bound dietary eicosapentaenoic acid (EPA) to support somatic growth and fecundity of Daphnia magna. In a growth experiment, supplementation of a C20 PUFA-deficient diet with free or phospholipid-bound EPA improved somatic growth rates of D. magna equally. However, the increase in fecundity was significantly more pronounced when phospholipid-bound EPA was provided. Free and phospholipid-bound EPA were provided in the same concentrations in our experiment, suggesting that the allocation to reproduction-related processes is affected differently by phospholipid-bound PUFA and free PUFA. Our finding stresses the need to consider the distribution of dietary PUFA in different lipid classes to gain a better understanding of how PUFA influence life history traits of Daphnids in the field.
Reciprocal selection between aphids, their protective endosymbionts, and the parasitoid wasps that prey upon them offers an opportunity to study the basis of their coevolution. We investigated adaptation to symbiont‐conferred defense by rearing the parasitoid wasp Lysiphlebus fabarum on aphids (Aphis fabae) possessing different defensive symbiont strains (Hamiltonella defensa). After ten generations of experimental evolution, wasps showed increased abilities to parasitize aphids possessing the H. defensa strain they evolved with, but not aphids possessing the other strain. We show that the two symbiont strains encode different toxins, potentially creating different targets for counter‐adaptation. Phenotypic and behavioral comparisons suggest that neither life‐history traits nor oviposition behavior differed among evolved parasitoid lineages. In contrast, comparative transcriptomics of adult female wasps identified a suite of differentially expressed genes among lineages, even when reared in a common, symbiont‐free, aphid host. In concurrence with the specificity of each parasitoid lineages’ infectivity, most differentially expressed parasitoid transcripts were also lineage‐specific. These transcripts are enriched with putative venom toxins and contain highly expressed, potentially defensive viral particles. Together, these results suggest that wild populations of L. fabarum employ a complicated offensive arsenal with sufficient genetic variation for wasps to adapt rapidly and specifically to their hosts’ microbial defenses.
Physiological and genomic variation among cryptic species of a marsh snail (Melampus bidentatus)
(2021)
Background
Parasitoid wasps have fascinating life cycles and play an important role in trophic networks, yet little is known about their genome content and function. Parasitoids that infect aphids are an important group with the potential for biological control. Their success depends on adapting to develop inside aphids and overcoming both host aphid defenses and their protective endosymbionts.
Results
We present the de novo genome assemblies, detailed annotation, and comparative analysis of two closely related parasitoid wasps that target pest aphids: Aphidius ervi and Lysiphlebus fabarum (Hymenoptera: Braconidae: Aphidiinae). The genomes are small (139 and 141 Mbp) and the most AT-rich reported thus far for any arthropod (GC content: 25.8 and 23.8%). This nucleotide bias is accompanied by skewed codon usage and is stronger in genes with adult-biased expression. AT-richness may be the consequence of reduced genome size, a near absence of DNA methylation, and energy efficiency. We identify missing desaturase genes, whose absence may underlie mimicry in the cuticular hydrocarbon profile of L. fabarum. We highlight key gene groups including those underlying venom composition, chemosensory perception, and sex determination, as well as potential losses in immune pathway genes.
Conclusions
These findings are of fundamental interest for insect evolution and biological control applications. They provide a strong foundation for further functional studies into coevolution between parasitoids and their hosts. Both genomes are available at https://bipaa.genouest.org.
Background
Parasitoid wasps have fascinating life cycles and play an important role in trophic networks, yet little is known about their genome content and function. Parasitoids that infect aphids are an important group with the potential for biological control. Their success depends on adapting to develop inside aphids and overcoming both host aphid defenses and their protective endosymbionts.
Results
We present the de novo genome assemblies, detailed annotation, and comparative analysis of two closely related parasitoid wasps that target pest aphids: Aphidius ervi and Lysiphlebus fabarum (Hymenoptera: Braconidae: Aphidiinae). The genomes are small (139 and 141 Mbp) and the most AT-rich reported thus far for any arthropod (GC content: 25.8 and 23.8%). This nucleotide bias is accompanied by skewed codon usage and is stronger in genes with adult-biased expression. AT-richness may be the consequence of reduced genome size, a near absence of DNA methylation, and energy efficiency. We identify missing desaturase genes, whose absence may underlie mimicry in the cuticular hydrocarbon profile of L. fabarum. We highlight key gene groups including those underlying venom composition, chemosensory perception, and sex determination, as well as potential losses in immune pathway genes.
Conclusions
These findings are of fundamental interest for insect evolution and biological control applications. They provide a strong foundation for further functional studies into coevolution between parasitoids and their hosts. Both genomes are available at https://bipaa.genouest.org.
Die 7. Fachtagung für Hochschuldidaktik, die 2016 erneut mit der DeLFI E-Learning Fachtagung Informatik stattfand, setzte das erfolgreiche Modell einer Tagung fort, die sich mit hochschuldidaktischen Fragen und der Gestaltung von Studiengängen der Informatik beschäftigt.
Thema der Tagung waren alle Fragen, die sich der Vermittlung von Informatikgegenständen im Hochschulbereich widmen. Dazu gehörten u.a.:
• fachdidaktische Konzepte der Vermittlung einzelner Informatikgegenstände
• methodische Lösungen, wie spezielle Lehr- und Lernformen, Durchführungskonzepte
• empirische Ergebnisse und Vergleichsstudien
• E-Learning-Ansätze, wenn sie ein erkennbares didaktisches Konzept verfolgen
• Studienkonzepte und Curricula, organisatorische Fragen, wie Gewinnung von Studierenden, Studieneingangsphase, Abbrecher.
Die Fachtagung widmete sich ausgewählten Fragestellungen dieses Themenkomplexes, die durch Vorträge ausgewiesener Experten, durch eingereichte Beiträge und durch Präsentationen und Poster intensiv behandelt wurden.
Unser besonderer Dank gilt dem Programmkomitee und den hier nicht genannten Helfern für ihren Einsatz bei der Vorbereitung und Durchführung der Tagung.
Das „Startprojekt“
(2016)
Absolventinnen und Absolventen unserer Informatik-Bachelorstudiengänge benötigen für kompetentes berufliches Handeln sowohl fachliche als auch überfachliche Kompetenzen. Vielfach verlangen wir von Erstsemestern in Grundlagen-Lehrveranstaltungen fast ausschließlich den Aufbau von Fachkompetenz und vernachlässigen dabei häufig Selbstkompetenz, Methodenkompetenz und Sozialkompetenz. Gerade die drei letztgenannten sind für ein erfolgreiches Studium unabdingbar und sollten von Anfang an entwickelt werden. Wir stellen unser „Startprojekt“ als einen Beitrag vor, im ersten Semester die eigenverantwortliche, überfachliche Kompetenzentwicklung in einem fachlichen Kontext zu fördern.
Diese Magisterarbeit ist dem bis heute sehr komplexen Geschlechterverhältnis gewidmet. Dieses Verhältnis werde ich analysieren, indem ich das literarische Motiv des Geschlechtertausches ausarbeite. Dabei werde ich seine kulturhistorische Entwicklung berücksichtigen. Das Thema wird interdisziplinär behandelt und zwar mithilfe anthropologischer, psychoanalytischer, literaturwissenschaftlicher sowie ideengeschichtlicher Perspektiven und Methoden – all dies um seine Komplexität zu erfassen. Zunächst wird die menschliche Geschlechtsidentität als ein naturbedingtes Phänomen einerseits und als ein kulturelles Konstrukt andererseits diskutiert. Die Psychoanalyse wird den feministischen Theorien entgegen gestellt, woraufhin sie sich als Versuch der Legitimierung der gesellschaftlichen Ordnung erweist. Die anschließende Analyse der kulturellen Repräsentationsformen des Weiblichen wird es deutlich machen, wie schwer es ist, die über mehrere Jahrhunderte tradierten Weiblichkeitsbilder zu „neutralisieren“. Die literarische Grundlage für die Untersuchung der Geschlechterbeziehungen verschaffen die drei „Geschichten über die Umwandlung der Verhältnisse“ (1980). In allen Texten vollzieht sich ein Geschlechtswandel: die Protagonistinnen schlüpfen in männliche Körper ein und auf einmal erfahren sie die Welt aus der bisher unbekannten Perspektive. Dabei empfindet jede von denen die neue Situation anders und doch so ähnlich. Anhand von Sarah Kirschs „Blitz aus dem heiterm Himmel“, Irmtraud Morgners „Gute Botschaft der Valeska in 73 Strophen“ und Christa Wolfs „Selbstversuch. Traktat zu einem Protokoll“ werden die regressiven patriarchalischen Strukturen aufgedeckt, in denen der Frau eine minderwertige Positionierung in einer Gesellschaft zugeschrieben wird. Da sich die Beziehungen zwischen Männern und Frauen in den gesellschaftlichen Machtverhältnissen widerspiegeln, werden die Geschichten im Kontext der sozialistischen Wirklichkeit der DDR in den 1970er Jahre analysiert. Aus diesen Untersuchungen ergeben sich klare Erkenntnisse: die Realität des „emanzipierten“ DDR-Staates hatte mit dem marxistischen Traum nichts zu tun. Diese in den Erzählungen widerspiegelte historisch-politische Wirklichkeit stellte die propagandistische Gleichberechtigung der Frauen in Frage. Die Sozialpolitik wird als eine der modernen männlichen Legitimationsstrategien für die Erhaltung der patriarchalischen Ordnung entschleiert. Damit die Frau nicht mehr über den Mann definiert wird, müsste eine grundlegende Veränderung der gesellschaftlichen Geschlechtsvorstellungen erfolgen. Alle in dieser Arbeit untersuchten Geschlechtertauschgeschichten beinhalten diverse Utopie-Entwürfe, die jedoch keine perfekte Ordnung darstellen. Ganz im Gegenteil – das sind eher negative Utopien, die fundamentale Kritik an der Ungleichheit der gesellschaftlichen Positionierung der Geschlechter zum Ziel haben. Christa Wolf, Irmtraud Morgner und Sarah Kirsch thematisierten in ihren Erzählungen die Problematik der Geschlechterverhältnisse in der DDR der 1970er Jahre und machten auf die Dringlichkeit des weiblichen Widerstandes aufmerksam. Gleichzeitig soll dieser literarische Diskurs die eigentliche Möglichkeit der Veränderung des gesellschaftlichen Status der Frauen aufzeigen. Daher sind diese imaginierten Geschlechtertauschgeschichten als Manifeste für wahre Gleichstellung der Frauen zu lesen.
Der vorliegende Beitrag untersucht das Potential und die Bedingungen alternativer Regulierungsformen vor dem Hintergrund von Better Regulation in Deutschland. Nahezu alle EU- und OECD-Staaten betreiben heute umfassende politische Reformprogramme zur Modernisierung der Regulierungsarchitekturen, die unter dem Label Better Regulation subsumiert werden. Die Zielsetzung dieser Programme besteht zum einen in der wirtschaftsfreundlichen Reduktion von Regulierungskosten und zum anderen in der Effektivitätssteigerung von Regulierung durch Vermeidung unintendierter Nebeneffekte. Better Regulation ist ein Toolkit verschiedener metaregulativer Policy-Instrumente, deren programmatische Zusammensetzung vom nationalen politischen Kontext abhängt. Im Rahmen der parallel verlaufenden Reformagenden werden überdies alternative Regulierungsformen von verschiedenen Advokaten besserer Regulierung thematisiert, und als Alternative zur rein staatlichen, hierarchischen Command-and-Control-Regulierung (CaC-Regulierung) promotet, jedoch weder näher auf deren Bedingungen noch deren Konsequenzen einzugehen. Den optimistischen Vorstellungen eines evidenzbasierten Regulatory Managements folgend, erfolgt die Prüfung und Analyse alternativer Regelungsformen im Zuge der Gesetzesfolgenabschätzung (GFA; Regulatory Impact Assessment RIA). Bisher fristen alternative Regulierungsformen allerdings ein Dasein im Schatten von Standardkosten-Modell, RIA und Co. und werden von den Policy-Makern nicht systematisch in Betracht gezogen oder eingesetzt. CaC-Regulierung ist und bleibt das dominante Steuerungsinstrument des Staates. Es existieren jedoch zahlreiche diskursive Anknüpfungspunkte einschließlich zahlreicher Kritiken an der hierarchisch-regulativen Steuerung, welche die Auseinandersetzung mit alternativen Regulierungsformen begründen. Ziel dieses Papieres ist es daher, die in der Kritik stehende CaC-Regulierung Modellen alternativer Regulierungsformen entgegenzustellen, wobei alternative Regulierung mit den Konzepten Selbstregulierung, Koregulierung und regulierter Selbstregulierung eng definiert wird, und nur jene Konstellationen betrachtet werden, die kooperativ zwischen Regierung und Wirtschaft operieren. Ebenso wird der Versuch unternommen, die mannigfaltigen Konzepte und Erscheinungsformen alternativer Regulierung zu definieren und zu kategorisieren. Im Anschluss an den theoretischen Part erfolgt im nächsten Schritt die Identifikation der Einsatz- und Erfolgsbedingungen alternativer Regulierung. Dies geschieht anhand zweier empirischer Fallbeispiele aus den Politikfeldern Berufsbildungspolitik („der Ausbildungspakt der deutschen Wirtschaft“) sowie Umweltpolitik („die Mehrwegquotenverpflichtung“), wobei gezielt ein erfolgreiches und gescheitertes Beispiel alternativer Regulierung verglichen werden und Erfolgsfaktoren abgeleitet werden. Das Ergebnis ist, dass alternative Regulierung gewisse Potentiale und Anreize für staatliche wie privatwirtschaftliche Akteure bietet, aber der Einsatz dieser Steuerungsformen höchst voraussetzungsvoll ist und nur in wenigen Politikfeldern möglich und zu empfehlen ist. So besteht das Potential alternativer Regulierungsformen vor allem in der ganzheitlichen Senkung von Regulierungskosten (Befolgungs- und Vollzugskosten) und in der Erhöhung der Steuerbarkeit der Adressaten. Allerdings sind die korporativen Akteure auf beiden Seiten zum einen nicht immer hinreichend auf diese Form indirekter Steuerung vorbereitet. Zum anderen wird alternative Regulierung durch die Fragmentierung und Schwäche von Wirtschaftsverbänden sowie durch Interessengegensätze unter den Regelungsadressaten gehindert, die in Trittbrettfahrertum und dem letztlichen Scheitern selbstregulativer Verpflichtungen münden. Als entscheidende, aber anspruchsvolle Erfolgskomponente erweisen sich die politische Kommunikation und die Durchsetzbarkeit staatlicher Sanktionen sowie die Erfolgskontrolle, um die Regelungseinhaltung durch die Wirtschaft zu gewährleisten. Generell ist zu konstatieren, dass alternative Regulierungsformen dort zustande kommen, wo sich konzentrierter Widerstand auf Seiten der Adressaten gegen geplante, autoritative Steuerung abzeichnet, eine gewisse Pfadabhängigkeit bzw. eine Historie sektoraler Selbstregulierung vorliegt und eine Win-Win-Situation bei der Kooperation für Politik und Wirtschaft ersichtlich ist. In der Konsequenz zeigen die Ergebnisse, dass alternative Regulierung nicht nach einem synoptisch-rationalen Modell politischer Prozesse entsteht, sondern ein ursprünglich nicht intendiertes Produkt Garbage Can-artiger Verhandlungen mit einem hohen Konfliktniveau darstellt. Folglich ist das Resultat für die Vorstellung einer „Rational Regulatory Choice“ induzierenden Better Regulation-Agenda desillusionierend.
In high-resolution solar physics, the volume and complexity of photometric, spectroscopic, and polarimetric ground-based data significantly increased in the last decade, reaching data acquisition rates of terabytes per hour. This is driven by the desire to capture fast processes on the Sun and the necessity for short exposure times "freezing" the atmospheric seeing, thus enabling ex post facto image restoration. Consequently, large-format and high-cadence detectors are nowadays used in solar observations to facilitate image restoration. Based on our experience during the "early science" phase with the 1.5 m GREGOR solar telescope (2014–2015) and the subsequent transition to routine observations in 2016, we describe data collection and data management tailored toward image restoration and imaging spectroscopy. We outline our approaches regarding data processing, analysis, and archiving for two of GREGOR's post-focus instruments (see http://gregor.aip.de), i.e., the GREGOR Fabry–Pérot Interferometer (GFPI) and the newly installed High-Resolution Fast Imager (HiFI). The heterogeneous and complex nature of multidimensional data arising from high-resolution solar observations provides an intriguing but also a challenging example for "big data" in astronomy. The big data challenge has two aspects: (1) establishing a workflow for publishing the data for the whole community and beyond and (2) creating a collaborative research environment (CRE), where computationally intense data and postprocessing tools are colocated and collaborative work is enabled for scientists of multiple institutes. This requires either collaboration with a data center or frameworks and databases capable of dealing with huge data sets based on virtual observatory (VO) and other community standards and procedures.
Broad-band imaging and even imaging with a moderate bandpass (about 1 nm) provides a photon-rich environment, where frame selection (lucky imaging) becomes a helpful tool in image restoration, allowing us to perform a cost-benefit analysis on how to design observing sequences for imaging with high spatial resolution in combination with real-time correction provided by an adaptive optics (AO) system. This study presents high-cadence (160 Hz) G-band and blue continuum image sequences obtained with the High-resolution Fast Imager (HiFI) at the 1.5-meter GREGOR solar telescope, where the speckle-masking technique is used to restore images with nearly diffraction-limited resolution. The HiFI employs two synchronized large-format and high-cadence sCMOS detectors. The median filter gradient similarity (MFGS) image-quality metric is applied, among others, to AO-corrected image sequences of a pore and a small sunspot observed on 2017 June 4 and 5. A small region of interest, which was selected for fast-imaging performance, covered these contrastrich features and their neighborhood, which were part of Active Region NOAA 12661. Modifications of theMFGS algorithm uncover the field-and structure-dependency of this imagequality metric. However, MFGS still remains a good choice for determining image quality without a priori knowledge, which is an important characteristic when classifying the huge number of high-resolution images contained in data archives. In addition, this investigation demonstrates that a fast cadence and millisecond exposure times are still insufficient to reach the coherence time of daytime seeing. Nonetheless, the analysis shows that data acquisition rates exceeding 50 Hz are required to capture a substantial fraction of the best seeing moments, significantly boosting the performance of post-facto image restoration.
It is shown that an elliptic scattering operator A on a compact manifold with boundary with operator valued coefficients in the morphisms of a bundle of Banach spaces of class (HT ) and Pisier’s property (α) has maximal regularity (up to a spectral shift), provided that the spectrum of the principal symbol of A on the scattering cotangent bundle avoids the right half-plane. This is accomplished by representing the resolvent in terms of pseudodifferential operators with R-bounded symbols, yielding by an iteration argument the R-boundedness of λ(A − λ)−1 in R(λ)≥ τ for some τ ∈ IR. To this end, elements of a symbolic and operator calculus of pseudodifferential operators with R-bounded symbols are introduced. The significance of this method for proving maximal regularity results for partial differential operators is underscored by considering also a more elementary situation of anisotropic elliptic operators on Rd with operator valued coefficients.
This commentary relates Hoerl & McCormack's dual systems perspective to models of cognitive development emphasizing representational redescription and the role of culturally constructed tools, including language, in providing flexible formats for thinking. We describe developmental processes that enable children to construct a mental time line, situate themselves in time, and overcome the primacy of the here and now.
GrassPlot is a collaborative vegetation-plot database organised by the Eurasian Dry Grassland Group (EDGG) and listed in the Global Index of Vegetation-Plot Databases (GIVD ID EU-00-003). GrassPlot collects plot records (releves) from grasslands and other open habitats of the Palaearctic biogeographic realm. It focuses on precisely delimited plots of eight standard grain sizes (0.0001; 0.001;... 1,000 m(2)) and on nested-plot series with at least four different grain sizes. The usage of GrassPlot is regulated through Bylaws that intend to balance the interests of data contributors and data users. The current version (v. 1.00) contains data for approximately 170,000 plots of different sizes and 2,800 nested-plot series. The key components are richness data and metadata. However, most included datasets also encompass compositional data. About 14,000 plots have near-complete records of terricolous bryophytes and lichens in addition to vascular plants. At present, GrassPlot contains data from 36 countries throughout the Palaearctic, spread across elevational gradients and major grassland types. GrassPlot with its multi-scale and multi-taxon focus complements the larger international vegetationplot databases, such as the European Vegetation Archive (EVA) and the global database " sPlot". Its main aim is to facilitate studies on the scale-and taxon-dependency of biodiversity patterns and drivers along macroecological gradients. GrassPlot is a dynamic database and will expand through new data collection coordinated by the elected Governing Board. We invite researchers with suitable data to join GrassPlot. Researchers with project ideas addressable with GrassPlot data are welcome to submit proposals to the Governing Board.
Lipid-containing adipocytes can dedifferentiate into fibroblast-like cells under appropriate culture conditions, which are known as dedifferentiated fat (DFAT) cells. However, the relative low dedifferentiation efficiency with the established protocols limit their widespread applications. In this study, we found that adipocyte dedifferentiation could be promoted via periodic exposure to cold (10 degrees C) in vitro. The lipid droplets in mature adipocytes were reduced by culturing the cells in periodic cooling/heating cycles (10-37 degrees C) for one week. The periodic temperature change led to the down-regulation of the adipogenic genes (FABP4, Leptin) and up-regulation of the mitochondrial uncoupling related genes (UCP1, PGC-1 alpha, and PRDM16). In addition, the enhanced expression of the cell proliferation marker Ki67 was observed in the dedifferentiated fibroblast-like cells after periodic exposure to cold, as compared to the cells cultured in 37 degrees C. Our in vitro model provides a simple and effective approach to promote lipolysis and can be used to improve the dedifferentiation efficiency of adipocytes towards multipotent DFAT cells.
Stem cells are capable of sensing and processing environmental inputs, converting this information to output a specific cell lineage through signaling cascades. Despite the combinatorial nature of mechanical, thermal, and biochemical signals, these stimuli have typically been decoupled and applied independently, requiring continuous regulation by controlling units. We employ a programmable polymer actuator sheet to autonomously synchronize thermal and mechanical signals applied to mesenchymal stem cells (MSC5). Using a grid on its underside, the shape change of polymer sheet, as well as cell morphology, calcium (Ca2+) influx, and focal adhesion assembly, could be visualized and quantified. This paper gives compelling evidence that the temperature sensing and mechanosensing of MSC5 are interconnected via intracellular Ca2+. Up-regulated Ca2+ levels lead to a remarkable alteration of histone H3K9 acetylation and activation of osteogenic related genes. The interplay of physical, thermal, and biochemical signaling was utilized to accelerate the cell differentiation toward osteogenic lineage. The approach of programmable bioinstructivity provides a fundamental principle for functional biomaterials exhibiting multifaceted stimuli on differentiation programs. Technological impact is expected in the tissue engineering of periosteum for treating bone defects.
Stem cells are capable of sensing and processing environmental inputs, converting this information to output a specific cell lineage through signaling cascades. Despite the combinatorial nature of mechanical, thermal, and biochemical signals, these stimuli have typically been decoupled and applied independently, requiring continuous regulation by controlling units. We employ a programmable polymer actuator sheet to autonomously synchronize thermal and mechanical signals applied to mesenchymal stem cells (MSC5). Using a grid on its underside, the shape change of polymer sheet, as well as cell morphology, calcium (Ca2+) influx, and focal adhesion assembly, could be visualized and quantified. This paper gives compelling evidence that the temperature sensing and mechanosensing of MSC5 are interconnected via intracellular Ca2+. Up-regulated Ca2+ levels lead to a remarkable alteration of histone H3K9 acetylation and activation of osteogenic related genes. The interplay of physical, thermal, and biochemical signaling was utilized to accelerate the cell differentiation toward osteogenic lineage. The approach of programmable bioinstructivity provides a fundamental principle for functional biomaterials exhibiting multifaceted stimuli on differentiation programs. Technological impact is expected in the tissue engineering of periosteum for treating bone defects.
Recruitment of mesenchymal stem cells (MSCs) to damaged tissue is a crucial step to modulate tissue regeneration. Here, the migration of human adipose-derived stem cells (hADSCs) responding to thermal and mechanical stimuli was investigated using programmable shape-memory polymer actuator (SMPA) sheets. Changing the temperature repetitively between 10 and 37 degrees C, the SMPA sheets are capable of reversibly changing between two different pre-defined shapes like an artificial muscle. Compared to non-actuating sheets, the cells cultured on the programmed actuating sheets presented a higher migration velocity (0.32 +/- 0.1 vs. 0.57 +/- 0.2 mu m/min). These results could motivate the next scientific steps, for example, to investigate the MSCs pre-loaded in organoids towards their migration potential.
Die G8 und Chinas Interessen
(2007)
Die G8 besitzt aus chinesischer Sicht große Entwicklungsmöglichkeiten. Verglichen mit anderen zwischenstaatlichen Organisationen hat die G8 einzigartige Vorteile angesichts ihrer Macht und Flexibilität. Um ihren Einfluss und ihre Kontrolle über die Weltangelegenheiten zu verstärken, sollte die Gruppe reformiert und erweitert werden. China ist gegenwärtig nicht an einem Beitritt zur G8 interessiert, wohl aber an einer engen Zusammenarbeit. Langfristig ist es allerdings nur eine Frage der Zeit, bis China der G8 beitreten wird.
Theory of mRNA degradation
(2012)
One of the central themes of biology is to understand how individual cells achieve a high fidelity in gene expression. Each cell needs to ensure accurate protein levels for its proper functioning and its capability to proliferate. Therefore, complex regulatory mechanisms have evolved in order to render the expression of each gene dependent on the expression level of (all) other genes. Regulation can occur at different stages within the framework of the central dogma of molecular biology. One very effective and relatively direct mechanism concerns the regulation of the stability of mRNAs. All organisms have evolved diverse and powerful mechanisms to achieve this. In order to better comprehend the regulation in living cells, biochemists have studied specific degradation mechanisms in detail. In addition to that, modern high-throughput techniques allow to obtain quantitative data on a global scale by parallel analysis of the decay patterns of many different mRNAs from different genes. In previous studies, the interpretation of these mRNA decay experiments relied on a simple theoretical description based on an exponential decay. However, this does not account for the complexity of the responsible mechanisms and, as a consequence, the exponential decay is often not in agreement with the experimental decay patterns. We have developed an improved and more general theory of mRNA degradation which provides a general framework of mRNA expression and allows describing specific degradation mechanisms. We have made an attempt to provide detailed models for the regulation in different organisms. In the yeast S. cerevisiae, different degradation pathways are known to compete and furthermore most of them rely on the biochemical modification of mRNA molecules. In bacteria such as E. coli, degradation proceeds primarily endonucleolytically, i.e. it is governed by the initial cleavage within the coding region. In addition, it is often coupled to the level of maturity and the size of the polysome of an mRNA. Both for S. cerevisiae and E. coli, our descriptions lead to a considerable improvement of the interpretation of experimental data. The general outcome is that the degradation of mRNA must be described by an age-dependent degradation rate, which can be interpreted as a consequence of molecular aging of mRNAs. Within our theory, we find adequate ways to address this much debated topic from a theoretical perspective. The improvements of the understanding of mRNA degradation can be readily applied to further comprehend the mRNA expression under different internal or environmental conditions such as after the induction of transcription or stress application. Also, the role of mRNA decay can be assessed in the context of translation and protein synthesis. The ultimate goal in understanding gene regulation mediated by mRNA stability will be to identify the relevance and biological function of different mechanisms. Once more quantitative data will become available, our description allows to elaborate the role of each mechanism by devising a suitable model.
The dimension of a variety V of algebras of a given type was introduced by E. Graczynska and D. Schweigert in [7] as the cardinality of the set of all derived varieties of V which are properly contained in V. In this paper, we characterize all solid varieties of dimensions 0, 1, and 2; prove that the dimension of a variety of finite type is at most N-0; give an example of a variety which has infinite dimension; and show that for every n is an element of N there is a variety with dimension n. Finally, we show that the dimension of a variety is related to the concept of the semantical kernel of a hypersubstitution and apply this connection to calculate the dimension of the class of all algebras of type tau = (n).
Hyperidentities and clones
(2000)
The theory of hyperidentities generalises the equational theory of universal algebras and is applicable in several fields of science, especially in computer sciences. This book presents the theory of hyperidentities and its relation to clone identities. The basic concept of hypersubstitution is used to introduce the monoid of hypersubstitutions, hyperidentities, M-hyperidentities, solid and M-solid varieties. This work integrates into a coherent framework many results scattered throughout the literature over the last eighteen years. In addition, the book contains some applications of hyperidentities to the functional completenes problem in multiple-valued logic. The general theory is also extended to partial algberas. The last chapter contains a list of exercises and open problems with suggestions of future work in this area of research.
Valuations of Terms
(2003)
Let tau be a type of algebras. There are several commonly used measurements of the complexity of terms of type tau, including the depth or height of a term and the number of variable symbols appearing in a term. In this paper we formalize these various measurements, by defining a complexity or valuation mapping on terms. A valuation of terms is thus a mapping from the absolutely free term algebra of type tau into another algebra of the same type on which an order relation is defined. We develop the interconnections between such term valuations and the equational theory of Universal Algebra. The collection of all varieties of a given type forms a complete lattice which is very complex and difficult to study; valuations of terms offer a new method to study complete sublattices of this lattice
M-solidity testing systems
(2002)
Let v be a valuation of terms of type tau, assigning to each term t of type tau a value v(t) greater than or equal to 0. Let k greater than or equal to 1 be a natural number. An identity s approximate to t of type tau is called k- normal if either s = t or both s and t have value greater than or equal to k, and otherwise is called non-k-normal. A variety V of type tau is said to be k-normal if all its identities are k-normal, and non-k-normal otherwise. In the latter case, there is a unique smallest k-normal variety N-k(A) (V) to contain V , called the k-normalization of V. Inthe case k = 1, for the usual depth valuation of terms, these notions coincide with the well-known concepts of normal identity, normal variety, and normalization of a variety. I. Chajda has characterized the normalization of a variety by means of choice algebras. In this paper we generalize his results to a characterization of the k-normalization of a variety, using k-choice algebras. We also introduce the concept of a k-inflation algebra, and for the case that v is the usual depth valuation of terms, we prove that a variety V is k-normal iff it is closed under the formation of k- inflations, and that the k-normalization of V consists precisely of all homomorphic images of k-inflations of algebras in V
Osnovi na Aritmetikata
(1999)