Sialylated glycans and glycoproteins are involved in cellular communication and are crucial for distinguishing between signal pathways. Sialylation levels and patterns modulate recognition events and are regulated by the enzymatic activity of sialyltransferases and neuraminidases. Abnormal activity of these enzymes is related to diseases such as cancer and viral infection. Monitoring these enzymatic activities offers valuable diagnostic tools. This work presents an impedimetric biosensing platform for following and detecting sialylation and desialylation processes. This platform is based on a native biantennary N-glycan substrate attached to a glassy carbon electrode. Changes in the molecular layer, as a result of enzymatic reactions, were detected by electrochemical impedance spectroscopy, displaying high sensitivity to the enzymatic surface reactions. Increase in the molecular layer roughness in response to the sialylation was visualized using atomic force microscopy. After enzymatic sialylation, the presence of sialic acid was confirmed using cyclic voltammetry by coupling of the redox active marker aminoferrocene. The sialylation showed selectivity toward the N-glycan compared to another glycan substrate. A time dependent sialylation was followed by electrochemical impedance spectroscopy, proving that the new system can be applied to evaluate the enzymatic kinetics. Our findings suggest that analyzing sialylation processes using this platform can become a useful tool for the detection of pathological states and pathogen invasion.
Sialylated glycans and glycoproteins are involved in cellular communication and are crucial for distinguishing between signal pathways. Sialylation levels and patterns modulate recognition events and are regulated by the enzymatic activity of sialyltransferases and neuraminidases. Abnormal activity of these enzymes is related to diseases such as cancer and viral infection. Monitoring these enzymatic activities offers valuable diagnostic tools. This work presents an impedimetric biosensing platform for following and detecting sialylation and desialylation processes. This platform is based on a native biantennary N-glycan substrate attached to a glassy carbon electrode. Changes in the molecular layer, as a result of enzymatic reactions, were detected by electrochemical impedance spectroscopy, displaying high sensitivity to the enzymatic surface reactions. Increase in the molecular layer roughness in response to the sialylation was visualized using atomic force microscopy. After enzymatic sialylation, the presence of sialic acid was confirmed using cyclic voltammetry by coupling of the redox active marker aminoferrocene. The sialylation showed selectivity toward the N-glycan compared to another glycan substrate. A time dependent sialylation was followed by electrochemical impedance spectroscopy, proving that the new system can be applied to evaluate the enzymatic kinetics. Our findings suggest that analyzing sialylation processes using this platform can become a useful tool for the detection of pathological states and pathogen invasion.
The aim of this publication is to critically rethink Manfred Böcker’s classic notion of “Antisemitismus ohne Juden” (Böcker, M. 2000. Antisemitismus ohne Juden: Die zweite Republik, die antirepublikanische Rechte und die Juden. Spanien 1931 bis 1936. Berlin: Peter Lang) and to translate it within the contemporary context of the Spanish Nationalpopulismus (Hirschmann, K. 2017. Der Aufstieg des Nationalpopulismus. Wie westliche Gesellschaften polarisiert werden. Bonn: Bundeszentrale für politische Bildung; Wilp, M. 2019. “Konfrontation statt Konsens: Der Aufschwung des Nationalpopulismus in den Niederlanden: Die politische Auseinandersetzung um Migration und Integration.” In Rechtspopulismus in Einwanderungsgesellschaften, edited by H. U. Brinkmann, and I. Panreck, 187–215. Wiesbaden: VS Verlag für Sozialwissenschaften) represented by the radical party Vox España. The existence of a formula of “Anti-Semitism without Jews and without Anti-Semites” (Botsch, G., and C. Kopke. 2016. “Antisemitismus ohne Antisemiten?” In Wut, Verachtung, Abwertung Rechtspopulismus in Deutschland, edited by R. Melzer, D. Molthagen, A. Zick, and B. Küpper, 178–194. Berlin: Friedrich Ebert Stiftung; Wodak, R. 2018. “The Radical Right and Antisemitism.” In The Oxford Handbook of the Radical Right, edited by J. Rydgren, 1–33. Oxford: Oxford Handbooks Online) seems to acquire corporeity in the “Civil-War-like” lexical arsenals (Rivas Venegas, M. 2018. Propaganda activities of Willi Münzenberg in Support of the Spanish Republic during the Spanish Civil War. An Approximation to His Visual and Rhetorical Communication Strategies. Berlin: Rosa Luxemburg Stiftung / Münzenberg Forum, 2019) of a party acutely connected to its Francoist past and to the paranoia of the “Francmason-Jewish-Bolshevist” conspiracy. This article aims to offer new perspectives on the study of national-populism via the parallel analysis of its “lexical arsenals” and visual-performative dispositives, what we here and in further publications identify as the messa in scena populista. It aims to fulfill the complex task of identifying the latent or indirect traces of Anti-Semitism in a party that chose the Muslim community as its preferred and most visible scapegoat, applied the tested political formula of the transnational nouvelle droite, yet never fully abandoned certain aspects of the Francoist and Spanish fascist worldview.
Semitransparency is an attractive and important property in solar cells since it opens new possibilities in a variety of applications such as tandem cell configuration and building-integrated photovoltaics. Metal halide perovskite has the optimal properties to function as the light harvester in solar cells and can be made as a thin film, while its chemical composition can change its band gap. However, achieving high transparency usually compromises the solar cell's efficiency. Here we report on a unique approach to fabricating semitransparent perovskite solar cells that does not rely on their composition or their thickness. The approach is based on a scalable process, inkjet printing of arrays of transparent pillars, which are composed of inert photopolymerizable liquid compositions and are partly covered by the perovskite. This material can be printed at specific locations and array densities, thus providing a digital control of both the transparency and efficiency of the solar cells. The new semitransparent device structure shows 11.2% efficiency with 24% average transparency without a top metal contact. Further development including deposition of a transparent contact enabled the fabrication of fully semitransparent devices with an efficiency of 10.6% and average transparency of 19%.
Functional amyloid proteins often appear as fibers in extracellular matrices of microbial soft colonies. In contrast to disease-related amyloid structures, they serve a functional goal that benefits the organism that secretes them, which is the reason for the title “functional”. Biofilms are a specific example of a microbial community in which functional amyloid fibers play a role. Functional amyloid proteins contribute to the mechanical stability of biofilms and mediate the adhesion of the cells to themselves as well as to surfaces. Recently, it has been shown that functional amyloid proteins also play a regulatory role in biofilm development. TasA is the major proteinaceous fibrilar component of the extracellular matrix of biofilms made of the soil bacterium and Gram-positive Bacillus subtilis. We have previously shown, as later corroborated by others, that in acidic solutions, TasA forms compact aggregates that are composed of tangled fibers. Here, we show that in a neutral pH and above a certain TasA concentration, the fibers of TasA are elongated and straight and that they bundle up in highly concentrated salt solutions. TasA fibers resemble the canonic amyloid morphology; however, these fibers also bear an interesting nm-scale periodicity along the fiber axis. At the molecular level, TasA fibers contain a twisted β-sheet structure, as indicated by circular dichroism measurements. Our study shows that the morphology of TasA fibers depends on the environmental conditions. Different fibrilar morphologies may be related with different functional roles in biofilms, ranging from granting biofilms with a mechanical support to acting as antibiotic agents.
This paper characterizes Medieval Hebrew and Aramaic as literary languages and seeks to explain how a 'literary language' namely a language used mainly in literary contexts arises, while utilizing three types of research: comparative philological research, which compares different languages and texts in terms of their vocabulary and grammar; sociolinguistic research, which examines the social functions of language use; and psycholinguistic research, which (in this particular case) examines issues of language acquisition. The paper builds on philological studies of literary languages to explain how the grammar of these languages evolves. It assumes that the acquisition of such languages is similar to second-language acquisition, while taking into account that these languages are both acquired and used in a strictly literary context. The main argument of the paper is that literary languages should be studied the same way as other languages, because ultimately after making some adjustments motivated by their particular functions they are compatible with the standard models of second-language acquisition.
Soil erosion affects agricultural landscapes worldwide, threatening food security and ecosystem viability. In arable environments, soil loss is primarily caused by short, intense rainstorms, typically characterized by high spatiotemporal variability. The complexity of erosive events challenges modeling efforts and explicit inclusion of extreme events in long-term risk assessment is missing. This study is intended to bridge this gap by quantifying the discrete and cumulative impacts of rainstorms on plot-scale soil erosion and providing storm-scale erosion risk analyses for a cropland region in northern Israel. Central to our analyses is the coupling of (1) a stochastic rainfall generator able to reproduce extremes down to 5-minute temporal resolutions; (2) a processes-based event-scale cropland erosion model (Dynamic WEPP, DWEPP); and, (3) a state-of-the-art frequency analysis method that explicitly accounts for rainstorms occurrence and properties. To our knowledge, this is the first study in which DWEPP runoff and soil loss are calibrated at the plot-scale on cropland (NSE is 0.82 and 0.79 for event runoff and sediment, respectively). We generated 300-year stochastic simulations of event runoff and sediment yield based on synthetic precipitation time series. Based on this data, the mean annual soil erosion in the study site is 0.1 kg m−2 [1.1 t ha−1]. Results of the risk analysis indicate that individual extreme rainstorms (>50 return period), characterized by high rainfall intensities (30-minute maximal intensity > $\sim$60 mm h−1) and high rainfall depth (>$\sim$200 mm), can trigger soil losses even one order of magnitude higher than the annual mean. The erosion efficiency of these rainstorms is mainly controlled by the short-duration (≤30 min) maximal intensities. The results demonstrate the importance of incorporating the impact of extreme events into soil conservation and management tools. We expect our methodology to be valuable for investigating future changes in soil erosion with changing climate.
Meandering channels and valleys are dominant landscape features on Earth. Their morphology and remnants potentially indicate past base-level fluctuations and changing regional slopes. The prevailing presence of meandering segments in low-slope areas somewhat confuses the physically based relationships between slope and channel meandering. This relationship underlies a fundamental debate: do incised sinuous channels actively develop during steepening of a regional slope, or do they inherit the planform of a preexisting sinuous channel through vertical incision? This question was previously explored through reconstructed evolution of meandering rivers, numerical simulations, and controlled, scaled-down laboratory experiments. Here, we study a rare, field-scale set of a dozen adjacent perennial channels, evolving in recent decades in a homogeneous erodible substrate in response to the Dead Sea level fall (> 30 m over 40 years). These channels are fed by perennial springs and have no drainage basin or previous fluvial history; they initiated straight and transformed into incising meandering channels following the emergence of the preexisting lake bathymetry, which resulted in increased channel lengths and regional slopes at different rates for each channel. This field setting allows testing the impact of changing regional slope on the sinuosity of a stream in the following cases: (a) relatively long and low-gradient shelf-like margins, (b) a sharp increase in the basinward gradient at the shelf-slope transition, and (c) gradually steepening slopes. Under a stable and low valley slope, the channels mainly incise vertically, inheriting a preexisting sinuous pattern. When the regional slope steepens, the channels start to meander, accompanying the vertical incision. The highest sinuosity evolved in the steepest channel, which also developed the deepest and widest valley. These results emphasize the amplifying impact of steepening regional slope on sinuosity. This holds when the flow is confined and chute cutoffs are scarce.
M.-A. Mroginski, S. Adam, G.S. Amoyal, A. Barnoy, A.-N. Bondar, V.A. Borin, J.R. Church, T. Domratcheva, B. Ensing, F. Fanelli, N. Ferré, O. Filiba, L. Pedraza-González, R. González, C.E. González-Espinoza, R.K. Kar, L. Kemmler, S.S. Kim, J. Kongsted, A.I. Krylov, Y. Lahav, M. Lazaratos, Q. NasserEddin, I. Navizet, A. Nemukhin, M. Olivucci, J.M.H. Olsen, A. Pérez de Alba Ortíz, E. Pieri, A.G. Rao, Y.M. Rhee, N. Ricardi, S. Sen, I.A. Solov'yov, L. De Vico, T.A. Wesolowski, C. Wiebeler, X. Yang, and I. Schapiro. 2021. “Frontiers in Multiscale Modeling of Photoreceptor Proteins.” Photochemistry and Photobiology, 97, 2, Pp. 243 - 269. Publisher's Version
Three-dimensional printing (3DP) is considered among the key-technologies for the next industrial revolution, with considerable effects on production processes, economy, and society. In this context, the most relevant part of the market consists of polymeric 3D printing. The 3D printable liquids are composed of various components, among them dyes are usually underrated because they are introduced merely for aesthetical reasons or to enhance the objects' resolution. In recent years, the capability of specific dyes to go beyond conventional use and to confer functional properties to 3D printed objects has become an emerging research area. Modifying elastic moduli upon light irradiation, inducing optical and emitting properties in the matrices or conferring temperature responsivity are just few examples of innovative stimuli-responsive materials that can be produced by combining well-designed dyes with the appropriate 3DP printed matrices. In this Review, we discuss and critically analyze the most relevant recent results achieved in the use of smart dyes in the synthesis of stimuli responsive 3D printed polymers.
Over the past few decades, numerous studies have examined the question of whether women and men tend to use different communicative styles, strategies, and practices. In this study, we employed a high-resolution algorithmic approach to examine the role of gender in structuring conflict news discourse, focusing on a comparison between the texts produced by foreign and domestic women and men journalists in their coverage of the Israeli-Palestinian conflict and the conflict in the Democratic Republic of the Congo. Extracting recurrent semantic patterns from over 80,000 texts, we show that women and men journalists tend to interpret journalistic professionalism in slightly different ways: While women emphasize precision and professional distance, men focus more on certitude and providing orientation. Moreover, women journalists tend to give more centrality to various groups of people in their coverage. We discuss these findings in the context of scholarship on gender and language use, journalism, and conflict.
