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Monodisperse Chemical Oligophosphorylation of Peptides via Protected Oligophosphorimidazolide Reagents
No full textProtein poly‐ and oligophosphorylation are recently discovered post‐translational modifications that remain poorly characterized due to (1) the difficulty of extracting endogenously polyphosphorylated species without degradation and (2) the absence of synthetic and analytical tools to prepare and characterize poly‐ and oligophosphorylated species in biochemical contexts. Herein, we report a methodology for the selective oligophosphorylation of peptides with monodisperse phosphate chain lengths (Pn=3–6). A library of oligophosphorimidazolide (oligoP‐imidazolide) reagents featuring benzyl and o‐nitrophenylethyl protecting groups was synthesized in moderate‐to‐good yields (65–93 %). These oligoP‐imidazolide reagents enabled the selective and simultaneous conjugation of multiple phosphate units to phosphoryl nucleophiles, circumventing tedious iterative processes. The generalizability of this approach is illustrated by a substrate scope study that includes several biologically relevant phosphopeptide sequences, culminating in the synthesis of >60 examples of peptide oligophosphates (Pn=2–6). Moreover, we report the preparation of oligoP‐diimidazolides (Pn=3–5) and discuss their application in generating unique condensed phosphate‐peptide conjugates. We also demonstrate that human phospho‐ubiquitin (pS65‐Ub) is amenable to functionalization by our reagents. Overall, we envision the methods described here will enable future studies that characterize these newly discovered but poorly understood phosphorylation modes.Foundation for the National Institutes of Health http://dx.doi.org/10.13039/100000009Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung http://dx.doi.org/10.13039/501100001711Peer Reviewe
Towards understanding the crystallization of photosystem II: influence of poly(ethylene glycol) of various molecular sizes on the micelle formation of alkyl maltosides
No full textThe influence of poly(ethylene glycol) (PEG) polymers H–(O–CH2–CH2)p–OH with different average molecular sizes p on the micelle formation of n-alkyl-β-D-maltoside detergents with the number of carbon atoms in the alkyl chain ranging from 10 to 12 is investigated with the aim to learn more about the detergent behavior under conditions suitable for the crystallization of the photosynthetic pigment–protein complex photosystem II. PEG is shown to increase the critical micelle concentration (CMC) of all three detergents in the crystallization buffer in a way that the free energy of micelle formation increases linearly with the concentration of oxyethylene units (O–CH2–CH2) irrespective of the actual molecular weight of the polymer. The CMC shift is modeled by assuming for simplicity that it is dominated by the interaction between PEG and detergent monomers and is interpreted in terms of an increase of the transfer free energy of a methylene group of the alkyl chain by 0.2 kJ mol−1 per 1 mol L−1 increase of the concentration of oxyethylene units at 298 K. Implications of this effect for the solubilization and crystallization of protein–detergent complexes as well as detergent extraction from crystals are discussed.Open access funding provided by Johannes Kepler University Linz.Austrian Science Fundhttp://dx.doi.org/10.13039/501100002428Germany's Excellence StrategyDeutsche Forschungsgemeinschafthttp://dx.doi.org/10.13039/501100001659Johannes Kepler University LinzPeer Reviewe
Mechanochemical ZIF-9 formation: in situ analysis and photocatalytic enhancement evaluation
No full textEfficient treatment of persistent pollutants in wastewater is crucial for sustainable water management and environmental protection. This study addresses this challenge by investigating the mechanochemical synthesis and photocatalytic performance of ZIF-9, a cobalt-based zeolitic imidazolate framework. Using synchrotron-based powder X-ray diffraction, we provide real-time insights into the formation dynamics of ZIF-9 during mechanosynthesis. Our results show that mechanochemically synthesised ZIF-9 exhibits superior photocatalytic activity compared to its solvothermally prepared counterpart, achieving a 2-fold increase in methylene blue degradation rate. This research not only advances our understanding of the synthesis and properties of ZIF-9, but also demonstrates the potential of mechanochemical approaches in the development of high-performance, sustainably produced materials for water treatment and other environmental applications.Peer Reviewe
»Darum gibt es im Grunde keine andre Beredsamkeit als die göttliche«. The Sermon and the Crisis of Rhetoric around 1800 – in the Perspectives of Literary Studies and Theology
No full textDer Beitrag betrachtet die verbreitete Diagnose einer ›Krise der Rhetorik‹ um 1800 aus der bisher weitgehend vernachlässigten Perspektive der Predigt. An vier exemplarischen Fällen wird gezeigt, wie die Rhetorik in der Predigt fortwirkt und sich transformiert. Franz Theremin bekräftigt noch einmal die Funktion der Rhetorik und repräsentiert die weitgehend ungebrochene Kontinuität rhetorischen Wissens in Homiletik und Predigtpraxis des 19. Jahrhunderts. Johann G. Fichte entwickelt das Format einer philosophischen Predigt, die gerade als Propädeutik der an sich antirhetorischen kritischen Philosophie dienen soll. Friedrich D. E. Schleiermacher entwickelt aus dem Problem der Mitteilbarkeit religiösen Wissens eine neue Konzeption der Predigt und auch ein höchst einflussreiches Konzept der Religion. Karl P. Moritz erzählt die Verkündigung kunstreligiöser Überlegungen und stellt im komischen Misslingen dieser Verkündigung gerade die Grenzen dieser Überlegungen aus. In der Zusammenschau der vier Fallstudien lässt sich die ›Krise der Rhetorik‹ differenzierter beschreiben und eine Predigtforschung entwerfen, die literaturwissenschaftliche und theologische Perspektiven verbindet.This article examines the widespread diagnosis of a »crisis of rhetoric« around 1800 from the hitherto largely neglected perspective of the sermon. Four exemplary cases are used to show how rhetoric continues and transforms itself. Franz Theremin reaffirms the function of rhetoric and represents the largely unbroken continuity of rhetorical knowledge in 19th century homiletics and preaching practice. Johann G. Fichte develops the format of a philosophical sermon supposed to serve precisely as a propaedeutic of critical philosophy, which is in itself anti-rhetorical. Friedrich D.E. Schleiermacher develops a new conception of the sermon and also a highly influential conception of religion from the problem of the communicability of religious knowledge. Karl P. Moritz proclaims a religion of art in the form of a sermon and narrates the comical failure of this proclamation, thus exposing the very limits of a sacralization of art. Through these four case studies we can gain a more precise understanding of the »crisis of rhetoric« and envision an interdisciplinary research on the sermon in which literary studies and theology would cooperate closely.Open Access funding enabled and organized by Projekt DEAL.Martin-Luther-Universität Halle-Wittenberg (1043)Peer Reviewe
Sich vorstellen (‘imagine’) as a Fiction Verb and as a Verb of Thinking
No full textI argue that sich vorstellen (‘imagine’) in German, similar to English imagine , has a use as a fiction verb and a use as a verb of thinking. I follow Vendler (Rev Métaphys Morale 84(2):161–173, 1979) in assuming that the fiction verbs like vorstellen can be used to report acts of subjective imagination (imagined inner experiences) and acts of objective imagination (imagined outer experiences). For sich vorstellen as a verb of thinking we have to distinguish between a use on which it introduces an activity and takes interrogative complements and DPs on a concealed question interpretation as arguments and a use on which it introduces an attitudinal state that can be characterized as betting on the truth of a proposition in a given subject matter. Given the differences in grammar and interpretation I argue that we have to distinguish four lexical entries for German sich vorstellen : imagine EXP-SBJ, imagine EXP-OBJ, imagine PROP-ACT, imagine PROP-STATE. Having laid out all the necessary distinctions to account for the data, I discuss the prospects of reducing the number of lexical entries. I propose that imagine EXP-SBJand imagine EXP-OBJcould be reduced to imagine PROP-ACTif we assume that all reports of experiential imagining can be reduced to reports of propositional imagining that combine the predicate imagine PROP-ACTwith a question of the kind ‘what would it be like?’, following an idea in D’Ambrosio and Stoljar (Synthese 199:12923–12944, 2021). Under this assumption only two lexical entries are needed: an entry for imagine PROP-ACT, a rogative predicate that introduces activities, and imagine PROP-STATEan attitude predicate that takes propositions as arguments and introduces an attitudinal state. The overall result is that the grammar and interpretation of the fiction verb sich vorstellen is much closer to verbs of thinking than one might imagine.Open Access funding enabled and organized by Projekt DEAL.Humboldt-Universität zu Berlin (1034)Peer Reviewe
White matter diffusion estimates in obsessive-compulsive disorder across 1653 individuals: machine learning findings from the ENIGMA OCD Working Group
No full textWhite matter pathways, typically studied with diffusion tensor imaging (DTI), have been implicated in the neurobiology of obsessive-compulsive disorder (OCD). However, due to limited sample sizes and the predominance of single-site studies, the generalizability of OCD classification based on diffusion white matter estimates remains unclear. Here, we tested classification accuracy using the largest OCD DTI dataset to date, involving 1336 adult participants (690 OCD patients and 646 healthy controls) and 317 pediatric participants (175 OCD patients and 142 healthy controls) from 18 international sites within the ENIGMA OCD Working Group. We used an automatic machine learning pipeline (with feature engineering and selection, and model optimization) and examined the cross-site generalizability of the OCD classification models using leave-one-site-out cross-validation. Our models showed low-to-moderate accuracy in classifying (1) “OCD vs. healthy controls” (Adults, receiver operator characteristic-area under the curve = 57.19 ± 3.47 in the replication set; Children, 59.8 ± 7.39), (2) “unmedicated OCD vs. healthy controls” (Adults, 62.67 ± 3.84; Children, 48.51 ± 10.14), and (3) “medicated OCD vs. unmedicated OCD” (Adults, 76.72 ± 3.97; Children, 72.45 ± 8.87). There was significant site variability in model performance (cross-validated ROC AUC ranges 51.6–79.1 in adults; 35.9–63.2 in children). Machine learning interpretation showed that diffusivity measures of the corpus callosum, internal capsule, and posterior thalamic radiation contributed to the classification of OCD from HC. The classification performance appeared greater than the model trained on grey matter morphometry in the prior ENIGMA OCD study (our study includes subsamples from the morphometry study). Taken together, this study points to the meaningful multivariate patterns of white matter features relevant to the neurobiology of OCD, but with low-to-moderate classification accuracy. The OCD classification performance may be constrained by site variability and medication effects on the white matter integrity, indicating room for improvement for future research.Peer Reviewe
Koszul modules with vanishing resonance in algebraic geometry
No full textWe discuss various applications of a uniform vanishing result for the graded components of the finite length Koszul module associated to a subspace K⊆⋀2V, where V is a vector space. Previously Koszul modules of finite length have been used to give a proof of Green’s Conjecture on syzygies of generic canonical curves. We now give applications to effective stabilization of cohomology of thickenings of algebraic varieties, divisors on moduli spaces of curves, enumerative geometry of curves on K 3 surfaces and to skew-symmetric degeneracy loci. We also show that the instability of sufficiently positive rank 2 vector bundles on curves is governed by resonance and give a splitting criterion.Peer Reviewe
The Handprint Initiative: Attitudes Towards the Environment in Mexican High Schools
No full textUNESCO’s new social contract for education states that we are at a turning point, facing multiple overlapping crises, and emphasizes the need to rebuild education so that it is relevant and adequate to meet today’s global challenges. According to Sustainable Development Goal 4.7, it is essential to have the knowledge and skills needed to promote sustainable development. The Handprint Initiative was born out of this need. It is founded on the social responsibility of educators and learners to actively participate in the decision-making process of our society. The objective of this research was to present the results of a large-scale implementation of the Handprint Initiative Instrument to identify the attitudes towards the environment. A 19-item survey was used to determine five key attitudes in several high schools in Mexico City. Based on the statistical tools (including principal component analysis, Kaiser–Meyer–Olkin and others), it was possible to measure Environmental Sensitivity, Ecocentrism, Techno-hope, Eco-apathy and Eco-indifference attitudes.Peer Reviewe
The elites of digitalisation. A change of leadership in the German economy?
No full textDie Digitalisierung der Wirtschaft sorgt für eine Dynamisierung der politischen Ökonomie. Neue und etablierte Akteur:innen konkurrieren um die Kontrolle digitalisierter Wertschöpfungsketten. Der vorliegende Beitrag unternimmt eine erste Strukturanalyse der Eliten dieses Feldes in Deutschland. Für die Untersuchung werden Lebensläufe und Netzwerke von 254 Personen analysiert, die Schlüsselpositionen im Kontext der Digitalisierung der deutschen Wirtschaft einnehmen. Es wird geprüft, inwiefern die Koordinations- und Personalstruktur des Feldes von Logiken der Transnationalisierung und Finanzialisierung geprägt ist, die für die digitale Ökonomie leitend sind. An einigen Stellen lässt sich eine Anpassung von Reproduktionsstrategien an die veränderten Spielregeln der Digitalisierung beobachten: so bei der zunehmenden Verbreitung kurzer Auslandsaufenthalte oder beim Bedeutungsgewinn finanzialisierter Managementkompetenz in der New Economy. Die Grundpfeiler der deutschen Elitenreproduktion bleiben jedoch unangetastet. Im Gegensatz zu soziologischen Erwägungen, die schon im Kontext der Globalisierung einen Bedeutungsverlust nationaler Eliten erwarteten, zeigt sich: Erstens besteht in Deutschlands digitalisierter Wirtschaft ein nationales industrielles Netzwerk von Spitzenmanager:innen fort, welches über Aufsichtsräte sowie Konsultations- und Verbandsgremien integriert ist. Zweitens konnten kaum Ausländer:innen in die digitale Elite aufrücken und finden prägende Karriereschritte überwiegend im Inland statt. Drittens dominieren weiterhin charakteristische Merkmale der deutschen Elitenformation – wie Hauskarrieren, das Studium an deutschsprachigen Massenuniversitäten oder die Möglichkeit von Karrieren, die auf technischer Kompetenz beruhen. Diese Ergebnisse sprechen dafür, dass die angestammten Eliten der deutschen Wirtschaft durch eine inkrementelle Anpassung ihrer Reproduktionsstrategien ihre Positionen auch im digitalen Kapitalismus behalten.Digitalisation of the economy means dynamisation of the political economy. New and established players are competing for control of digitalised value chains. This article undertakes a first structural analysis of the elites in this field in Germany. The study analyses the CVs and networks of 254 individuals who occupy key positions in the context of the digitalisation of the German economy. It examines to which extent the coordination and personnel structure of the field is shaped by the logics of transnationalisation and financialisation. In some places, an adaptation of reproduction strategies to the changed rules of digitalisation can be observed: for example, in the increasing prevalence of short stays abroad or the growing importance of financialised management skills in the new economy. However, the cornerstones of German elite reproduction remain untouched. In contrast to sociological considerations which already expected a loss of importance of national elites in the context of globalisation, the following is evident: Firstly, a national industrial network of top managers continues to exist in Germany’s digitalised economy, which is integrated via supervisory boards as well as advisory bodies and association structures. Secondly, hardly any foreigners have been able to move up into the digital elite and formative career steps take place predominantly in Germany. Transnationalisation and financialisation have found their way into the personal careers of digital elites in Germany, but to a rather limited extent, especially in the industrial core. Thirdly, characteristic features of the German elite formation continue to dominate – such as careers at home, studying at German-language mass universities, or the possibility of careers based on technical expertise. These results suggest that the traditional elites of the German economy, by incrementally adapting their reproduction strategies, will retain their positions in digital capitalism.Open Access funding enabled and organized by Projekt DEAL.Humboldt-Universität zu Berlin (1034)Peer Reviewe
Identification and amplification of candidate genes for virus defence in common ash (Fraxinus excelsior L.)
No full textAcross various European countries, Fraxinus excelsior L. is facing a decline caused by Hymenoscyphus fraxineus . The underlying mechanisms of the disease are still insufficiently understood in detail. Observations suggest that, in addition to the main pathogen, viral infections may also contribute to the decline of ash trees. We described homologues in the F. excelsior genome of formerly annotated virus resistance genes in model species and tested the applicability of primers on these gene fragments. Further, a prediction of cis-acting regulatory elements and transcription factor binding sites was accomplished, to determine the exact location of the promoters of these genes in the ash genome. After annotation and filtering the low-complexity regions, primers for use with genomic DNA were designed on sequences that showed a high degree of similarity and equality in length to translated regions and promoters of these regions. From the newly designed primers, those with the most favourable primer selection parameters were selected and tested on eight virus infected—four symptomatic and four asymptomatic—samples. The amplified products were analysed by agarose gel electrophoresis. From all producing one-band amplicons, 36 primer pairs amplifying translated, and 36 primers amplifying promoter regions were selected. Our study is the first step of a SNP discovery and marker development test. The further marker development on these sequences could be useful for the selection of ash individuals with various resistance to viral infections, providing a route for a more thorough understanding of the ash dieback–virus resistance interaction.Open Access funding enabled and organized by Projekt DEAL.Waldklimafondshttp://dx.doi.org/10.13039/501100010297Technologie- und Förderzentrum im Kompetenzzentrum für Nachwachsende Rohstoffe (5324)Peer Reviewe