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Seasonal variations in landslide activity remain understudied compared to recent advances in landslide early warning at hourly to daily timescales.
Here, we learn the seasonal pattern of monthly landslide activity in the Pacific Northwest from five heterogeneous landslide inventories with differing spatial and temporal coverage and reporting protocols combined in a Bayesian multi-level model.
We find that landslide activity is distinctly seasonal, with credible increases in landslide intensity, inter-annual variability, and probability marking the onset of the landslide season in November.
Peaks in landslide probability in January and intensity in February lag the annual peak in mean monthly precipitation and landslide activity is more variable in winter than in summer, when landslides are rare.
For a given monthly rainfall, landslide intensity at the season peak in February is up to 10 times higher than at the onset in November, underlining the importance of antecedent seasonal hillslope conditions.
The development of interface technologies is driven by the goal of making interaction more positive through natural action-control mappings.
In Virtual Reality (VR), the entire body is potentially involved for interaction, using such mappings with a maximum of degrees of freedom. The downside is the increase in interaction complexity, which can dramatically influence interface design.
A cognitive perspective on detailed aspects of interaction patterns is lacking in common interface design guidelines, although it can be helpful to make this complexity controllable and, thus, make interaction behavior predictable.
In the present study, the distinction between grounding, embodiment, and situatedness (the GES framework) is applied to organize aspects of interactions and to compare them with each other.
In two experiments, zooming into or out of emotional pictures through changes of arm span was examined in VR. There are qualitatively different aspects during such an interaction: i) perceptual aspects caused by zooming are fundamental for human behavior (Grounding: closer objects appear bigger) and ii) aspects of gestures correspond to the physical characteristics of the agents (Embodiment: little distance of hands signals little or, in contrast, "creating more detail").
The GES-framework sets aspects of Grounding against aspects of Embodiment, thus allowing to predict human behavior regarding these qualitatively different aspects.
For the zooming procedure, the study shows that Grounding can overrule Embodiment in interaction design.
Thus, we propose GES as a cognitive framework that can help to inform interaction guidelines for user interface design in VR.
Sulfur mustard (SM) and its derivatives are potent genotoxic agents, which have been shown to trigger the activation of poly (ADP-ribose) polymerases (PARPs) and the depletion of their substrate, nicotinamide adenine dinucleotide (NAD+). NAD+ is an essential molecule involved in numerous cellular pathways, including genome integrity and DNA repair, and thus, NAD+ supplementation might be beneficial for mitigating mustard-induced (geno)toxicity. In this study, the role of NAD+ depletion and elevation in the genotoxic stress response to SM derivatives, i.e., the monofunctional agent 2-chloroethyl-ethyl sulfide (CEES) and the crosslinking agent mechlorethamine (HN2), was investigated with the use of NAD+ booster nicotinamide riboside (NR) and NAD+ synthesis inhibitor FK866. The effects were analyzed in immortalized human keratinocytes (HaCaT) or monocyte-like cell line THP-1. In HaCaT cells, NR supplementation, increased NAD+ levels, and elevated PAR response, however, did not affect ATP levels or DNA damage repair, nor did it attenuate long- and short-term cytotoxicities. On the other hand, the depletion of cellular NAD+ via FK866 sensitized HaCaT cells to genotoxic stress, particularly CEES exposure, whereas NR supplementation, by increasing cellular NAD+ levels, rescued the sensitizing FK866 effect. Intriguingly, in THP-1 cells, the NR-induced elevation of cellular NAD+ levels did attenuate toxicity of the mustard compounds, especially upon CEES exposure. Together, our results reveal that NAD+ is an important molecule in the pathomechanism of SM derivatives, exhibiting compound-specificity. Moreover, the cell line-dependent protective effects of NR are indicative of system-specificity of the application of this NAD+ booster.
kappa-casein (kappa-CN) is one of the key components in bovine milk, playing a unique role in the structuration of casein micelles.
It contains in its chemical structure up to sixteen amino acid residues (mainly serine and threonine) susceptible to modifications, including glycosylation and phosphorylation, which may further be formed during milk processing.
In this study, changes in post-translational modification (PTM) of kappa-CN during bovine milk fermentation were investigated. One-to-five-day fermented milk samples were produced.
A traditional bottom-up proteomics approach was used to establish a multiple-reaction monitoring (MRM) method for relative quantification of kappa-CN PTM. Endoproteinase Glu-C was found to efficiently digest the kappa-CN molecule.
The developed LC-MS method was validated by performing assessments of linearity, precision, repeatability, reproducibility, limit of detection (LOD), and limit of quantification (LOQ).
Among the yielded peptides, four of them containing serine and threonine residues were identified and the unmodified as well as the modified variants of each of them were relatively quantified. These peptides were (1) IPTINTIASGEPTSTTE ([140, 158]), (2) STVATLE ([162, 168]), (3) DSPE ([169, 172]), and (4) INTVQVTSTAV ([180, 190]). Distribution analysis between unmodified and modified peptides revealed that over 50% of kappa-CN was found in one of its modified forms in milk.
The fermentation process further significantly altered the composition between unmodified/modified kappa-CN, with glycoslaytion being predominant compared to phosphorylation (p < 0.01).
Further method development towards alpha and beta-CN fractions and their PTM behavior would be an asset to better understand the changes undergone by milk proteins and the micellar structure during fermentation.
This international curricular review provides a structured overview of the particle physics content in 27 state, national, and international high-school physics curricula. The review was based on a coding manual that included 60 concepts that were identified as relevant for high-school particle physics education.
Two types of curricula were reviewed, namely curricula with a dedicated particle physics chapter and curricula without a dedicated particle physics chapter.
The results of the curricular review show that particle physics concepts are explicitly or implicitly present in all reviewed curricula.
However, the number of particle physics concepts that are featured in a curriculum varies greatly across the reviewed curricula. We identified core particle physics concepts that can be found in most curricula. Here, elementary particles, fundamental interactions, and charges were identified as explicit particle physics concepts that are featured in more than half of the reviewed curricula either as content or context. Indeed, theoretical particle physics concepts are more prominent in high-school physics curricula than experimental particle physics concepts.
Overall, this international curricular review provides the basis for future curricular development with respect to particle physics and suggests an increased inclusion of experimental particle physics concepts in high-school physics curricula.
We consider the initial value problem for the Navier-Stokes equations over R-3 x [0, T] with time T > 0 in the spatially periodic setting.
We prove that it induces open injective mappings A(s): B-1(s) -> B-2(s-1) where B-1(s), B-2(s-1) are elements from scales of specially constructed function spaces of Bochner-Sobolev typeparametrized with the smoothness index s is an element of N.
Finally, we prove that a map Asis surjective if and only if the inverse image A(s)(- 1) (K) of any pre compact set K from the range of the map Asis bounded in the Bochner space L-s([0, T], L-r(T-3))with the Ladyzhenskaya-Prodi-Serrin numbers s, r.
Information regarding the spatial distribution of soil water content is key in many disciplines and applications including soil and atmospheric sciences, hydrology, and agricultural engineering.
Thus, within the past decades various experimental methods and strategies have been developed to map spatial variations in soil moisture distribution and to monitor temporal changes.
Our study examines the combination of electrical resistivity mapping and point observations of soil moisture to infer the spatial and the temporal variability of soil moisture.
Over a period of around two years, we performed field measurements on six days to collect repeated electrical resistivity mapping data for a nine-hectare test site south-east of Berlin, Germany.
Permanently installed TDR probes, temporary TDR measurements within permanently installed tubes, and gravimetric measurements using soil samples provided soil moisture data at various selected points.
In addition, soil analysis and classification results are available for 132 regularly distributed positions up to depths of 1.2 m.
We compare and link three-dimensional resistivity models obtained via data inversion to soil composition and soil moisture as provided by our point data.
Both the soil samples and the resistivity models indicate a two-layer medium characterized by a sandy top layer with varying thickness and a loamy bottom soil.
For all six field campaigns, we observe similar resistivity patterns reflecting the temporally stable influence of soil texture.
While the overall patterns are stable, the range of resistivity values changes with soil moisture. Finally, to estimate spatial models of soil moisture, we link our soil moisture and resistivity data using empirical petrophysical models relying on a second order polynomial function.
We observe a mean prediction error for soil moisture of +/-0.034 m3 & BULL; m? 3 using all observation points while we notice that point-specific models further reduce the error.
Thus, we conclude that our experimental and data analysis strategies represent a reliable approach to establish site-specific models and to estimate three-dimensional moisture distribution including temporal variations.
The work is devoted to the use of electrokinetic phenomena in liquid crystals to create a new class of microfluidics devices - optofluidics, designed to control electromagnetic radiation, including the THz frequency range.
To achieve the goal, an optical method is used to study changes in the orientational structure in LC layers caused by a shear flow generated by electroosmotic pumps. Simula-tion of LC behaviour in an experimental cell containing electroosmotic pumps and flat layers of a nematic liquid crystal is fulfilled.
The experimental depend-ences of the intensity of polarized radiation passing through flat LC layers on the control voltage applied to the electroosmotic pump and the results of calcu-lations of the hydrodynamic and mechano-optical characteristics of the experi-mental LC cell are presented.
The propagation of THz irradiation across the multilayer structure of the optofluidic cell is considered taking into account the minimum number of re-reflections of waves from different layers and the ab-sorption of THz irradiation in a propylene and a liquid crystal.
A remarkable peculiarity of videoconferencing (VC) applications – the self-view – a.k.a. digital mirror, is examined as a potential reason behind the voiced exhaustion among users. This work draws on technostress research and objective self-awareness theory and proposes the communication role (sender vs. receiver) as an interaction variable. We report the results of two studies among European employees (n1 = 176, n2 = 253) with a one-year time lag. A higher frequency of self-view in a VC when receiving a message, i.e., listening to others, indirectly increases negative affect (study 1 & 2) and exhaustion (study 2) via the increased state of public self-awareness. Self-viewing in the role of message sender, e.g., as an online presenter, also increases public self-awareness, but its overall effects are less harmful. As for individual differences, users predisposed to public self-consciousness were more concerned with how other VC participants perceived them. Gender effects were insignificant.
We consider Bayesian inference for large-scale inverse problems, where computational challenges arise from the need for repeated evaluations of an expensive forward model.
This renders most Markov chain Monte Carlo approaches infeasible, since they typically require O(10(4)) model runs, or more.
Moreover, the forward model is often given as a black box or is impractical to differentiate.
Therefore derivative-free algorithms are highly desirable. We propose a framework, which is built on Kalman methodology, to efficiently perform Bayesian inference in such inverse problems.
The basic method is based on an approximation of the filtering distribution of a novel mean-field dynamical system, into which the inverse problem is embedded as an observation operator.
Theoretical properties are established for linear inverse problems, demonstrating that the desired Bayesian posterior is given by the steady state of the law of the filtering distribution of the mean-field dynamical system, and proving exponential convergence to it.
This suggests that, for nonlinear problems which are close to Gaussian, sequentially computing this law provides the basis for efficient iterative methods to approximate the Bayesian posterior.
Ensemble methods are applied to obtain interacting particle system approximations of the filtering distribution of the mean-field model; and practical strategies to further reduce the computational and memory cost of the methodology are presented, including low-rank approximation and a bi-fidelity approach.
The effectiveness of the framework is demonstrated in several numerical experiments, including proof-of-concept linear/nonlinear examples and two large-scale applications: learning of permeability parameters in subsurface flow; and learning subgrid-scale parameters in a global climate model.
Moreover, the stochastic ensemble Kalman filter and various ensemble square-root Kalman filters are all employed and are compared numerically.
The results demonstrate that the proposed method, based on exponential convergence to the filtering distribution of a mean-field dynamical system, is competitive with pre-existing Kalman-based methods for inverse problems.
Nature conservation is currently shaping many terrestrial ecosystems in Africa.
This is particularly evident in Sub-Saharan Africa (SSA), where conservation is intended to recover wildlife populations, with special focus on elephants.
Rising numbers of elephants induce woody biomass losses but increase soil organic carbon (SOC) stocks from decaying wood and dung.
We hypothesized that these increases under wildlife conservation in SSA go along with rising contents of plant residues in SOC, traceable by the molecular markers lignin and n-alkanes.
In contrast, agricultural intensification would reduce them due to lower C input and faster SOC turnover through tillage.
To test this, we analyzed lignin by the CuO oxidation method and n-alkanes by fast pressurized solvent extraction in topsoils (0-10 cm) of Arenosols and corresponding plant samples (trees, grasses and crops).
Sampling sites followed conservation gradients with low, medium and high elephant densities and intensification gradients with rangeland and cropland in the woodland savanna of the Namibian Zambezi Region.
Patterns of lignin-derived phenols were retained in the soil, whereas n-alkanes showed shifts in chain lengths. n-Alkanes also showed no clear increase or decrease under conservation or intensification, respectively.
Differently, lignin-derived phenols showed lower values under intensification than under conservation. Confirming our hypothesis, rising SOC contents with rising elephant densities (from 4.4 at low to 5.7 g kg(-1) SOC at high elephant densities) went along with an increasing accumulation of lignin-derived phenols (24.4-34.8 g kg(-1) VSCOC).
This increase is associated with the input of woody debris to the soil, as indicated by V-units and carbon isotopes, modulated by clay and woody biomass.
We conclude, that increasing input of woody residues into soil by browsing behaviour of elephants is an important mechanism for controlling SOC supply in the context of wildlife conservation and is traceable with lignin-derived phenols, but not with n-alkanes.
We report on the effect of spatially correlated noise on the velocities of self-propelled particles.
Correlations in the random forces acting on self-propelled particles can induce directed collective motion, i.e., swarming.
Even with repulsive coupling in the velocity directions, which favors a disordered state, strong correlations in the fluctuations can align the velocities locally leading to a macroscopic, turbulent velocity field.
On the other hand, while spatially correlated noise is aligning the velocities locally, the swarming transition to globally directed motion is inhibited when the correlation length of the noise is nonzero, but smaller than the system size.
We analyze the swarming transition in d-dimensional space in a mean field model of globally coupled velocity vectors.
Rhizophagus irregularis is one of the most extensively studied arbuscular mycorrhizal fungi (AMF) that forms symbioses with and improves the performance of many crops. Lack of transformation protocol for R. irregularis renders it challenging to investigate molecular mechanisms that shape the physiology and interactions of this AMF with plants.
Here, we used all published genomics, transcriptomics, and metabolomics resources to gain insights into the metabolic functionalities of R. irregularis by reconstructing its high-quality genome-scale metabolic network that considers enzyme constraints. Extensive validation tests with the enzyme-constrained metabolic model demonstrated that it can be used to (i) accurately predict increased growth of R. irregularis on myristate with minimal medium; (ii) integrate enzyme abundances and carbon source concentrations that yield growth predictions with high and significant Spearman correlation (rS = 0.74) to measured hyphal dry weight; and (iii) simulate growth rate increases with tighter association of this AMF with the host plant across three fungal structures.
Based on the validated model and system-level analyses that integrate data from transcriptomics studies, we predicted that differences in flux distributions between intraradical mycelium and arbuscles are linked to changes in amino acid and cofactor biosynthesis.
Therefore, our results demonstrated that the enzyme-constrained metabolic model can be employed to pinpoint mechanisms driving developmental and physiological responses of R. irregularis to different environmental cues.
In conclusion, this model can serve as a template for other AMF and paves the way to identify metabolic engineering strategies to modulate fungal metabolic traits that directly affect plant performance.
IMPORTANCE Mounting evidence points to the benefits of the symbiotic interactions between the arbuscular mycorrhiza fungus Rhizophagus irregularis and crops; however, the molecular mechanisms underlying the physiological responses of this fungus to different host plants and environments remain largely unknown.
We present a manually curated, enzyme-constrained, genome-scale metabolic model of R. irregularis that can accurately predict experimentally observed phenotypes.
We show that this high-quality model provides an entry point into better understanding the metabolic and physiological responses of this fungus to changing environments due to the availability of different nutrients.
The model can be used to design metabolic engineering strategies to tailor R. irregularis metabolism toward improving the performance of host plants.
Using novel longitudinal data, this paper studies the short- and medium-term effects of Russia's invasion of Ukraine on February 24, 2022 on social trust of adolescents in Germany. Comparing adolescents who responded to our survey shortly before the start of the war with those who responded shortly after the conflict began and applying difference-in-differences (DiD) models over time, we find a significant decline in the outcome after the war started. These findings provide new evidence on how armed conflicts influence social trust and well-being among young people in a country not directly involved in the war.
Der Beitrag beleuchtet die Perspektiven von DaF und DaZ im Kontext von Mehrsprachigkeit.
Zunächst wird ein Verständnis von ‚Mehrsprachigkeitʻ erarbeitet und diskutiert. Anschließend wird gezeigt, wie sich DaZ, DaF und die Forschung zu Varietäten des Deutschen im Ausland im Rahmen dieses Verständnisses von Mehrsprachigkeit positionieren lassen.
Der Beitrag schließt mit einem Plädoyer für ein neues, integratives Konzept von ‚Deutsch im Mehrsprachigkeitskontextʻ.
Language development in children with a heritage language background is often characterized by a shift towards the majority language once children enter formal educational contexts.
In Germany, educational programs that target heritage languages are scarce.
It is therefore of interest whether children with a heritage language background can benefit from a bilingual program targeting their heritage language.
In this paper, we report data on the lexical skills of Italian heritage children in two educational contexts, bilingual Italian-German kindergartens and a bilingual Italian-German elementary school.
We examine (1) developmental trajectories of children's lexical skills in German and Italian, (2) differences between noun and verb development, (3) differences between lexical production and comprehenand Italian, kindergarteners showed balanced receptive vocabulary skills.
By contrast, elementary school-children had a larger German than Italian vocabulary. Both groups demonstrated a clear dominance of nouns over verbs.
While school children already performed at ceiling in German at the end of first grade, across the school years, their Italian vocabulary increased, nouns in particular.
Critical anthropology? On the relation between philosophical anthropology and critical theory
(2022)
This article compares Max Horkheimer's and Theodor W. Adorno's foundation of the Frankfurt Critical Theory with Helmuth Plessner's foundation of Philosophical Anthropology.
While Horkheimer's and Plessner's paradigms are mutually incompatible, Adorno's << negative dialectics >> and Plessner's << negative anthropology >> (G. Gamm) can be seen as complementing one another.
Jurgen Habermas at one point sketched a complementary relationship between his own publicly communicative theory of modern society and Plessner's philosophy of nature and human expressivity, and though he then came to doubt this, he later reaffirmed it. Faced with the << life power >> in << high capitalism >> (Plessner), the ambitions for a public democracy in a pluralistic society have to be broadened from an argumentative focus (Habermas) to include the human condition and the expressive modes of our experience as essentially embodied persons. The article discusses some possible aspects of this complementarity under the title of a << critical anthropology >> (H. Schnädelbach).
Mit Spannung wird die Entscheidung des BVerfG zu § 362 Nr. 5 StPO erwartet. Die Verfassungsbeschwerde des Beschuldigten, der vor Jahrzehnten vom Vorwurf des Mordes rechtskräftig freigesprochen worden war und der nun befürchten muss, auf der Grundlage des § 362 Nr. 5 StPO wegen derselben Tat verurteilt zu werden, hat die verfassungsrechtliche Überprüfung der Vorschrift veranlasst. Zuvor waren bereits in zahlreichen Texten von Rechtswissenschaftlern Argumente für und gegen die Regelung ausgetauscht worden. Verständlicherweise steht dabei Art. 103 Abs. 3 GG im Vordergrund. Wer § 362 Nr. 5 StPO ablehnt, begründet das in erster Linie mit einer Verletzung des ne-bis-in-idem-Grundsatzes. Nicht wenige Befürworter der erweiterten Wiederaufnahmemöglichkeit verweisen – gefühlsgeleitet − auf „materielle Gerechtigkeit“ sowie auf „schlechterdings unerträgliche Ergebnisse“. Unbefriedigend ist das für Menschen, die es weder ungerecht noch unerträglich finden, dass ein Tatverdächtiger nach rechtskräftigem Freispruch bis an sein Lebensende als „unschuldig“ gilt und zwar auch, wenn auf Grund neuer Beweismittel aus dem Freigesprochenen ein zu lebenslanger Freiheitsstrafe Verurteilter werden könnte. Dass das Festhalten am rechtskräftigen Freispruch richtig ist, dafür gibt es starke juristische Gründe. Auch für die Durchbrechung des Strafklageverbrauchs in den von § 362 Nr. 5 StPO erfassten Fällen gibt es gewiss beachtliche Gründe. Sie sind meines Erachtens jedoch nicht gewichtig genug. Im vorliegenden Text soll die verfassungsrechtliche Dimension außen vor bleiben. Eine neue Vorschrift, mit der das geltende Strafprozessrecht verändert wird, muss auch eine Prüfung am Maßstab des geltenden Strafprozessrechts durchlaufen, um akzeptiert werden zu können. § 362 Nr. 5 StPO fällt bei dieser Prüfung durch und sollte deshalb aufgehoben werden.
Der untenstehende Text ist eine recht spontane Reaktion auf Bemerkungen, die jüngst von den Kollegen Armin Engländer und Christian Rückert zu einem Kodifizierungsvorschlag für die Regelungsthemen Notwehr, Notwehrexzess und subjektives Rechtfertigungselement in der Zeitschrift „Goltdammer’s Archiv für Strafrecht“ präsentiert wurden. Den Entwurfstext hat eine – kleine – Gruppe von Strafrechtslehrern erarbeitet. Er wurde letztes Jahr mittels eines Aufsatzes von Elisa Hoven und Wolfgang Mitsch – ebenfalls im „Goltdammer’s Archiv“ − vorgestellt und erläutert. Engländer und Rückert äußern stellenweise Zustimmung, üben aber auch zu vielen Punkten des Entwurfs und seiner Begründung Kritik. Da der hiesige Verfasser sowohl an der Entwicklung des Entwurfstextes als auch an dem genannten GA-Aufsatz als Ko-Autor beteiligt war, möchte er − im Folgenden: ich − zu einigen der Kritiken Stellung nehmen.
Lanthanide based ceria nanomaterials are important practical materials due to the redox properties that are useful in the avenues pertaining to technology and life sciences. Sub 10 nm spherical and highly monodisperse Ce1−xYbxO2−y (0.04 ≤ x ≤ 0.22) nanoparticles were synthesized by thermal decomposition, annealed separately at 773 K and 1273 K for 2 hours and characterized. Elemental mapping for Yb3+ doped ceria nanoparticles shows homogeneous distribution of Yb3+ atoms in the ceria with low Yb3+ content annealed at 773 K and 1273 K for 2 hours. However, clusters are observed for 773 K annealed ceria samples with high concentration of Yb3+. These clusters are not detected in 1273 K annealed nanomaterials. Introducing small amounts of Yb3+ ions into the ceria lattice as spectroscopic probes can provide detailed information about the atomic structure and local environments allowing the monitoring of small structural changes, such as clustering. The emission spectra observed at room temperature and at 4 K have a manifold of bands that corresponds to the 2F5/2 → 2F7/2 transition of Yb3+ ions. Some small shifts are observed in the Stark splitting pattern depending on the sample and the annealing conditions. The deconvolution by PARAFAC analysis yielded luminescence decay kinetics as well as the associated luminescence spectra of three species for each of the low Yb3+ doped ceria samples annealed at 773 K and one species for the 1273 K annealed samples. However, the ceria samples with high concentration of Yb3+ annealed at the two temperatures showed only one species with lower decay times as compared to the low Yb3+ doped ceria samples.
Dass unser geltendes Strafrecht eine „Verschlankung“ vertragen könnte, ist nun auch im Bundesjustizministerium bemerkt worden. Aus dem Besonderen Teil sollen Vorschriften entfernt werden, die aus unterschiedlichen Gründen nicht (mehr) benötigt werden. Als weitere Maßnahme der Entkriminalisierung steht möglicherweise die punktuelle Senkung von Strafrahmen auf der Agenda. Dies hat nicht nur eine Reduzierung des Sanktionsniveaus zur Folge, sondern kann dort, wo infolge der niedrigeren Strafrahmenuntergrenze aus Verbrechen Vergehen werden, Straflosigkeit bewirken. Das betrifft § 30 StGB, eine Vorschrift, die Anlass für die Überlegungen sein kann, nicht nur im Besonderen Teil, sondern auch im Allgemeinen Teil des StGB nach entbehrlichen Normen zu suchen. § 30 StGB ist aktuell anwendbar in Kombination mit den Tatbestandsvarianten des § 184b StGB, die Verbrechenscharakter haben. Welche strafrechtlichen Ergebnisse daraus resultieren können, ist in der Debatte um die Strafbarkeit von Kinderpornographie bislang nicht erörtert worden. Dasselbe gilt für den praktisch selten zur Anwendung kommenden § 16 Abs. 2 StGB, der neuerdings in Verbindung mit § 184b StGB und § 184c StGB in Erscheinung getreten ist. Aus der Betrachtung der Zusammenhänge dieser Vorschriften lassen sich einige Empfehlungen an die Gesetzgebung ableiten.
Mit Urteil vom 31. Oktober 2023 hat der 2. Senat des BVerfG die im Dezember 2021 durch „Gesetz zur Herstellung materieller Gerechtigkeit“ eingeführte Vorschrift § 362 Nr. 5 StPO für mit dem Grundgesetz unvereinbar und deshalb nichtig erklärt. Erwartungsgemäß waren die Reaktionen auf diese Entscheidung nicht nur zustimmende. Die vorliegende Anmerkung wendet sich nicht gegen das Ergebnis, setzt sich aber − auch kritisch − mit einigen Teilen der Entscheidungsbegründung sowie den Erwiderungen der beiden abweichend votierenden Senatsmitglieder auseinander.
Cell division and the resulting changes to the cell organization affect the shape and functionality of all tissues.
Thus, understanding the determinants of the tissue-wide changes imposed by cell division is a key question in developmental biology.
Here, we use a network representation of live cell imaging data from shoot apical meristems (SAMs) in Arabidopsis thaliana to predict cell division events and their consequences at the tissue level.
We show that a support vector machine classifier based on the SAM network properties is predictive of cell division events, with test accuracy of 76%, which matches that based on cell size alone.
Furthermore, we demonstrate that the combination of topological and biological properties, including cell size, perimeter, distance and shared cell wall between cells, can further boost the prediction accuracy of resulting changes in topology triggered by cell division.
Using our classifiers, we demonstrate the importance of microtubule-mediated cell-to-cell growth coordination in influencing tissue-level topology.
Together, the results from our network-based analysis demonstrate a feedback mechanism between tissue topology and cell division in A. thaliana SAMs.
In plants, the trehalose biosynthetic pathway plays key roles in the regulation of carbon allocation and stress adaptation.
Engineering of the pathway holds great promise to increase the stress resilience of crop plants.
The synthesis of trehalose proceeds by a two-step pathway in which a trehalose-phosphate synthase (TPS) uses UDP-glucose and glucose-6-phosphate to produce trehalose-6 phosphate (T6P) that is subsequently dephosphorylated by trehalose-6 phosphate phosphatase (TPP).
While plants usually do not accumulate high amounts of trehalose, their genome encodes large families of putative trehalose biosynthesis genes, with many members lacking obvious enzymatic activity.
Thus, the function of putative trehalose biosynthetic proteins in plants is only vaguely understood. To gain a deeper insight into the role of trehalose biosynthetic proteins in crops, we assessed the enzymatic activity of the TPS/TPP family from tomato (Solanum lycopersicum L.) and investigated their expression pattern in different tissues as well as in response to temperature shifts. From the 10 TPS isoforms tested, only the 2 proteins belonging to class I showed enzymatic activity, while all 5 TPP isoforms investigated were catalytically active.
Most of the TPS/TPP family members showed the highest expression in mature leaves, and promoter-reporter gene studies suggest that the two class I TPS genes have largely overlapping expression patterns within the vasculature, with only subtle differences in expression in fruits and flowers.
The majority of tomato TPS/TPP genes were induced by heat stress, and individual family members also responded to cold.
This suggests that trehalose biosynthetic pathway genes could play an important role during temperature stress adaptation.
In summary, our study represents a further step toward the exploitation of the TPS and TPP gene families for the improvement of tomato stress resistance.
There is consensus that word retrieval starts with activation of semantic representations.
However, in adults without language impairment, relatively little attention has been paid to the effects of the semantic attributes of to-be-retrieved words.
This paper, therefore, addresses the question of which item-inherent semantic factors influence word retrieval.
Specifically, it reviews the literature on a selection of these factors: imageability, concreteness, number of semantic features, typicality, intercorrelational density, featural distinctiveness, concept distinctiveness, animacy, semantic neighbourhood density, semantic similarity, operativity, valence, and arousal.
It highlights several methodological challenges in this field, and has a focus on the insights from studies with people with aphasia where the effects of these variables are more prevalent.
The paper concludes that further research simultaneously examining the effects of different semantic factors that are likely to affect lexical co-activation, and the interaction of these variables, would be fruitful, as would suitably scaled computational modelling of these effects in unimpaired language processing and in language impairment.
Such research would enable the refinement of theories of semantic processing and word production, and potentially have implications for diagnosis and treatment of semantic and lexical impairments.
For the first time, synchrotron X-ray refraction radiography (SXRR) has been paired with in-situ heat treatment to monitor microstructure and porosity evolution as a function of temperature.
The investigated material was a laser powder bed fusion (LPBF) manufactured AlSi10Mg, where the initial eutectic Si network is known to disintegrate and spherodize into larger particles with increasing temperature.
Such alloy is also prone to ther-mally induced porosity (TIP).
We show that SXRR allows detecting the changes in the Si-phase morphology upon heating, while this is currently possible only using scanning electron microscopy. SXRR also allows observing the growth of pores, usually studied via X-ray computed tomography, but on much smaller fields-of-view.
Our results show the great potential of in-situ SXRR as a tool to gain in-depth knowledge of the susceptibility of any material to thermally induced damage and/or microstructure evolution over statistically relevant volumes.
Photo-iniferter (PI)-RAFT polymerization, the direct activation of chain transfer agents via light, is a fascinating polymerization technique, as it overcomes some restriction of conventional RAFT polymerization.
As such, we elucidated the role of reversible deactivation in this context using a monomer-CTA pair with low chain transfer capabilities.
Tests with varying targeted degrees of polymerization (DP) or monomer concentrations revealed no significant improvement of polymerization control using the PI-process. Control can however be achieved via slow monomer addition, increasing the number of activation/deactivation events per monomer addition.
More importantly, the livingness of the polymerization was found to be extraordinarily high, enabling the straightforward and rapid synthesis of multiblock copolymers with up to 20 blocks and a high number of repeating units per block (DP = 25-100) maintaining an overall excellent definition (M-n = 90 300 g mol(-1), D = 1.29).
This study highlights the enormous potential of PI-RAFT polymerization for the synthesis of polymeric materials.
Klausur im Medienrecht
(2024)
Die Privatsphäre prominenter Personen wird häufig durch eine auf Sensationsgier ausgerichtete Presseberichterstattung gefährdet. Während sich die Presse dabei vordergründig auf ein öffentliches Interesse an solchen Berichten beruft, kann die Reputation der Betroffenen in der Öffentlichkeit stark und dauerhaft beeinträchtigt werden. Jedoch folgen aus dem Allgemeinen Persönlichkeitsrecht mehrere Ansprüche, mit denen diese Rechtsverletzungen abgewehrt und mögliche Schäden kompensiert werden können.
Residential segregation is a wide-spread phenomenon that can be observed in almost every major city.
In these urban areas residents with different racial or socioeconomic background tend to form homogeneous clusters.
Schelling's famous agent-based model for residential segregation explains how such clusters can form even if all agents are tolerant, i.e., if they agree to live in mixed neighborhoods.
For segregation to occur, all it needs is a slight bias towards agents preferring similar neighbors.
Very recently, Schelling's model has been investigated from a game-theoretic point of view with selfish agents that strategically select their residential location.
In these games, agents can improve on their current location by performing a location swap with another agent who is willing to swap.
We significantly deepen these investigations by studying the influence of the underlying topology modeling the residential area on the existence of equilibria, the Price of Anarchy and on the dynamic properties of the resulting strategic multi-agent system. Moreover, as a new conceptual contribution, we also consider the influence of locality, i.e., if the location swaps are restricted to swaps of neighboring agents.
We give improved almost tight bounds on the Price of Anarchy for arbitrary underlying graphs and we present (almost) tight bounds for regular graphs, paths and cycles. Moreover, we give almost tight bounds for grids, which are commonly used in empirical studies.
For grids we also show that locality has a severe impact on the game dynamics.
The majority of middle-age children do not meet current physical activity guidelines. There is growing evidence that adults' physical activity is partially influenced by automatic affective processes, which are derived from affective experiences with physical activity.
However, little is known about whether these processes are interrelated with children's physical activity level.
A prospective design was used to examine whether automatic affective processes assessed by an evaluative priming procedure predict physical activity of children.
Physical activity of 48 children (8.71 +/- 0.71 years; 65% girls) was measured for 1 week with activity trackers.
In a linear regression model, automatic affective processes (beta = 0.36) significantly predicted physical activity, accounting for 11.02% of variance.
These results indicate that physical-activity-related automatic affective processes are associated with children's physical activity, as has previously been found in adults.
This study emphasizes the importance of fostering positive affective experiences associated with physical activity during childhood.
The educational sector currently faces a massive digital transformation with various digital offerings entering the market. To provide some orientation in this transforming space, a national digital education platform (NDEP) is under development in Germany as part of a nationwide flagship project. On the one hand, in efficiently connecting the relevant stakeholders to each other and to value-adding education-related offerings, various benefits emerge. On the other hand, monopolising the educational sector and influencing the respective market through a state-controlled platform bears potential regulatory risks from misuse of power by the platform to malpractice by the users. Against this background, we aim to identify and systematise these potential drawbacks prior to the platform’s actual development and implementation. We pursue a qualitative, interpretivist approach for policy analysis, based on ten elite interviews and two workshops. Our results are threefold: (1) We capture the consolidated NDEP architecture; (2) We categorise the range of relevant functions and value propositions of the NDEP; (3) We derive 23 regulatory areas of conflict across the three building blocks that result from the potential ecosystem and function scope configurations of the NDEP. As a contribution to research, we shed new interdisciplinary light on the governance and infrastructure of public-private platforms that enable innovation and collaboration while integrating respective market segments. As a contribution to practice, we provide clear guidance for policy-makers in strategizing the development and governance of and through national digital platforms in education.
Purpose
Rehabilitation professionals are faced with judging and describing the social-medicine status of their patients. Rehabilitation professionals must know the core concepts of acute unfitness for work, psychological capacities, and long-term work capacity.
Acquiring and applying this knowledge, requires training. The research question is if and to what extent medical professionals and students' knowledge changes after social medicine training.
Methods
This quasi-experimental study was carried out in the real-life context of social medicine training. Psychology students (n = 42), physicians/psychotherapists (i.e. state-licensed health professionals) (n = 44) and medical assistant professionals (n = 29) were trained. Their social medicine knowledge was measured before and after training by a 10-min expert-approved and content valid knowledge questionnaire.
Three free-text questions had to be answered on the essential aspects of present and prognostic work ability and psychological capacities.
Answers were rated for correctness by two experts. Paired t tests and variance analysis have been calculated for group comparisons.
Results
All groups improved their social medicine knowledge from the pre- to the post-test. The students started with the lowest level of knowledge in the pre-test.
After training, 69% of the physicians/psychotherapists and 56.8% of the medical assistant professionals, but only 7% of the students, obtained maximum scores for naming psychological capacities.
Conclusions
Social medicine knowledge increased after a training course consisting of eight lessons. The increase was greater for medical assistant professionals and physicians/psychotherapists than for students. Social medicine training must be adjusted to the trainee groups' knowledge levels.
Cities and other human settlements are major contributors to climate change and are highly vulnerable to its impacts. They are also uniquely positioned to reduce greenhouse gas emissions and lead adaptation efforts. These compound challenges and opportunities require a comprehensive perspective on the public policy of human settlements. Drawing on core literature that has driven debate around cities and climate over recent decades, we put forward a set of boundary objects that can be applied to connect the knowledge of epistemic communities and support an integrated urbanism. We then use these boundary objects to develop the Goals-Intervention-Stakeholder-Enablers (GISE) framework for a public policy of human settlements that is both place-specific and provides insights and tools useful for climate action in cities and other human settlements worldwide. Using examples from Berlin, we apply this framework to show that climate mitigation and adaptation, public health, and well-being goals are closely linked and mutually supportive when a comprehensive approach to urban public policy is applied.
Tuning systems of traditional Georgian singing determined from a new corpus of field recordings
(2022)
In this study we examine the tonal organization of the 2016 GVM dataset, a newly-created corpus of high-quality multimedia field recordings of traditional Georgian singing with a focus on Svaneti. For this purpose, we developed a new processing pipeline for the computational analysis of non-western polyphonic music which was subsequently applied to the complete 2016 GVM dataset.
To evaluate under what conditions a single tuning system is representative of current Svan performance practice, we examined the stability of the obtained tuning systems from an ensemble-, a song-, and a corpus-related perspective.
Furthermore, we compared the resulting Svan tuning systems with the tuning systems obtained for the Erkomaishvili dataset (Rosenzweig et al., 2020) in the study by Scherbaum et al. (2020). In comparison to a 12-TET (12-tone-equal-temperament) system, the Erkomaishvili and the Svan tuning systems are surprisingly similar.
Both systems show a strong presence of pure fourths (500 cents) and fifths (700 cents), and 'neutral' thirds (peaking around 350 cents) as well as 'neutral' sixths.
In addition, the sizes of the melodic and the harmonic seconds in both tuning systems differ systematically from each other, with the size of the harmonic second being systematically larger than the melodic one.
"Bad" data has a direct impact on 88% of companies, with the average company losing 12% of its revenue due to it.
Duplicates - multiple but different representations of the same real-world entities are among the main reasons for poor data quality, so finding and configuring the right deduplication solution is essential.
Existing data matching benchmarks focus on the quality of matching results and neglect other important factors, such as business requirements. Additionally, they often do not support the exploration of data matching results.
To address this gap between the mere counting of record pairs vs. a comprehensive means to evaluate data matching solutions, we present the Frost platform.
It combines existing benchmarks, established quality metrics, cost and effort metrics, and exploration techniques, making it the first platform to allow systematic exploration to understand matching results.
Frost is implemented and published in the open-source application Snowman, which includes the visual exploration of matching results, as shown in Figure 1.
How much influence did the former communist state security service Darzhavna sigurnost (DS) have during the transformation period in Bulgaria?
For the first time in history, there is empirical data available that allow for an analysis of the role of the Bulgarian secret police and its "afterlife" after 1990.
Bulgarian intelligence archives, which were made partly accessible following the country's admission to the European Union in 2007, provide an excellent basis for an analysis of the relationship between the DS and the Soviet State Committee for Security, the transformation of the Bulgarian security apparatus in 1990, attempts to disclose the state security archives, and continuous infiltration of Bulgarian politics, institutions, and security apparatus by former agents of the communist intelligence and security apparatus.
The empirical data suggest that personal connections, dependencies, and informal networks of former DS agents and officials played an important role during the transformation period in Bulgaria and are at least partly responsible for political corruption, continuous Russian influence, a high degree of politicization of the Bulgarian security apparatus, misuse of intelligence and illegal surveillance practices, and a high degree of domestic and international mistrust and (dis-)loyalty.
Uncovering the digitalization impact on consumer decision-making for checking accounts in banking
(2022)
Checking account providers must understand the importance of digital and non-digital service attributes across different customer segments to achieve a product-market fit in digitalization. In particular, various latent personal characteristics influence customer choices in digital banking. However, there is only limited research on banking customer behavior beyond the technology acceptance model, and none that explores customer preferences for checking accounts experimentally. Against this background, we present the results of a discrete choice experiment on customer preferences towards checking accounts in Germany. The outcome of the paper is a detailed quantitative assessment of the relationships between checking account service attributes and a set of latent influencing factors on choice. While customer service experience, the scope of services, and professional expertise are identified as re-occurring critical aspects for customers when choosing their banking service provider, the type of provider and digital product innovation showed little impact on customer choice overall. In multigroup analyses, we reveal the moderating impact of influencing factors on the preference of checking account service attributes. Additional segmentation analyses point to six customer segments from which four still prefer a traditional operating model. The largest segment of traditional product-innovative customers prefers digitalized, i.e., data-driven checking accounts in a mixed-mode with human customer advisory and on-site branch services from a traditional bank. At the other end of the spectrum, a small innovative Fintech customer segment, influenced by non-pragmatism and social norms, prefers a purely digital operating model with data-driven applications in banking.
Detecting DNA of novel fungal pathogens using ResNets and a curated fungi-hosts data collection
(2022)
Background:
Emerging pathogens are a growing threat, but large data collections and approaches for predicting the risk associated with novel agents are limited to bacteria and viruses. Pathogenic fungi, which also pose a constant threat to public health, remain understudied.
Relevant data remain comparatively scarce and scattered among many different sources, hindering the development of sequencing-based detection workflows for novel fungal pathogens.
No prediction method working for agents across all three groups is available, even though the cause of an infection is often difficult to identify from symptoms alone.
Results:
We present a curated collection of fungal host range data, comprising records on human, animal and plant pathogens, as well as other plant-associated fungi, linked to publicly available genomes.
We show that it can be used to predict the pathogenic potential of novel fungal species directly from DNA sequences with either sequence homology or deep learning.
We develop learned, numerical representations of the collected genomes and visualize the landscape of fungal pathogenicity.
Finally, we train multi-class models predicting if next-generation sequencing reads originate from novel fungal, bacterial or viral threats.
Conclusions:
The neural networks trained using our data collection enable accurate detection of novel fungal pathogens.
A curated set of over 1400 genomes with host and pathogenicity metadata supports training of machine-learning models and sequence comparison, not limited to the pathogen detection task.
After a long history of floodplain degradation and substantial losses of inundation areas over the last decades, a rethinking of floodplain management has taken place in Germany.
Floodplains are now acknowledged as important areas for both biodiversity and society. This transformation has been significantly supported by nationwide research activities. A systematic assessment of the current floodplain management is still lacking.
We therefore developed a scheme to assess floodplain management through the steps of identification, analysis, implementation, and evaluation.
Reviewing the data and literature on nationwide floodplain-related research and activities, we defined key elements of floodplain management for Germany.
We concluded that research activities already follow a strategic nationwide approach of identifying and analyzing floodplains.
Progress in implementation is slow, however, and potentials are far from being reached.
Nevertheless, new and unique initiatives enable Germany to stay on the long-term path of giving rivers more space and improving floodplain conditions.
Pichia pastoris (syn. Komagataella phaffii) represents a commonly used expression system in the biotech industry. High clonal variation of transformants, however, typically results in a broad range of specific productivities for secreted proteins. To isolate rare clones with exceedingly high product titers, an extensive number of clones need to be screened.
In contrast to high-throughput screenings of P. pastoris clones in microtiter plates, secrete-and -capture methodologies have the potential to efficiently isolate high-producer clones among millions of cells through fluorescence-activated cell sorting (FACS).Here, we describe a novel approach for the non-covalent binding of fragment antigen-binding (Fab) proteins to the cell surface for the isolation of high-producing clones.
Eight different single-chain variable fragment (scFv)-based capture matrices specific for the constant part of the Fabs were fused to the Saccharomyces cerevisiae alpha -agglutinin (SAG1) anchor protein for surface display in P. pastoris. By encoding the capture matrix on an episomal plasmid harboring inherently unstable autonomously replicating sequences (ARS), this secrete-and -capture system offers a switchable scFv display.
Efficient plasmid clearance upon removal of selective pres-sure enabled the direct use of isolated clones for subsequent Fab production. Flow-sorted clones (n = 276) displaying high amounts of Fabs showed a significant increase in median Fab titers detected in the cell-free supernatant (CFS) compared to unsorted clones (n = 276) when cells were cultivated in microtiter plates (fac-tor in the range of-21-49). Fab titers of clones exhibiting the highest product titer observed for each of the two approaches were increased by up to 8-fold for the sorted clone.
Improved Fab yields of sorted cells vs. unsorted cells were confirmed in an upscaled shake flask cultivation of selected candidates (factor in the range of-2-3). Hence, the developed display-based selection method proved to be a valuable tool for efficient clone screening in the early stages of our bioprocess development.
Die Schulinspektion evaluiert Schulen mit dem Ziel der Qualitätssicherung von Unterrichts- und Schulqualität.
Dies gilt insbesondere für Schulen, an denen „erheblicher Entwicklungsbedarf“ festgestellt wurde.
Diese Schulen bekommen zusätzliche Unterstützung, erfahren aber auch zusätzlichen Druck durch diese Einordnung.
Die weitere Entwicklung dieser Schulen ist bisher kaum erforscht. Diese Studie untersucht mit Daten der Schulinspektion, der amtlichen Statistik und Leistungsdaten von 333 Berliner Grundschulen Veränderungen in Indikatoren der Unterrichts- und Schulqualität, der Schulleistung, und der Zusammensetzung der Schülerschaft (SES und Anteil mit nicht-deutscher Herkunftssprache) nach der Diagnose „erheblicher Entwicklungsbedarf“.
Die empirischen Analysen zeigten, dass sich bei diesen Schulen die Unterrichts- und Schulqualität nur geringfügig veränderte, sich der Leistungsabstand zu allen anderen Grundschulen nicht statistisch signifikant verringerte, und sich die Zusammensetzung der Schülerschaft hinsichtlich des sozioökonomischen Status (SES) nicht veränderte. Jedoch erhöhte sich der Anteil von Kindern mit nicht-deutscher Herkunftssprache statistisch signifikant.
In this paper, we define a variant of Roe algebras for spaces with cylindrical ends and use this to study questions regarding existence and classification of metrics of positive scalar curvature on such manifolds which are collared on the cylindrical end.
We discuss how our constructions are related to relative higher index theory as developed by Chang, Weinberger, and Yu and use this relationship to define higher rho-invariants for positive scalar curvature metrics on manifolds with boundary.
This paves the way for the classification of these metrics.
Finally, we use the machinery developed here to give a concise proof of a result of Schick and the author, which relates the relative higher index with indices defined in the presence of positive scalar curvature on the boundary.
The literature on social inequality in study abroad almost exclusively focuses on university students.
This paper systematically examines the role of socioeconomic status (SES) for study abroad intent (SAI) and uptake across all levels of pre-college education in Japan, thereby also providing a first in-depth empirical study on pre-college study abroad (PSA) in this country.
Drawing on theories of social inequality (especially the effectively main-tained inequality (EMI) thesis) in combination with elements from cumulative advantage and life course research, we understand the intention and final decision to study abroad as an outcome of SES-specific differ-ences in educational biographies, with higher SES families seeking transnational education for their children to achieve status advantages.
Using large-scale cross-sectional data for Japan (N = 15,450) for children aged three to eighteen years, binary and generalized ordered logit regressions show that children from high SES families are generally more likely to (1) express SAI (especially for college) and take up PSA; and (2) choose more exclusive forms of PSA, i.e. earlier and more lengthy stays. Findings further indicate that (3) the SES-gap in the likelihood to show SAI or take up PSA is highest at the pre-and high school levels.
Applying the KHB method we found that (4) the percentage of SES effects on SAI mediated through earlier PSA experience is marginal or even reversed at times. We conclude that early PSA experience is positively related to further SAI, with high SES students likely accumulating transnational human capital to a greater extent, possibly acquiring status advantages.
In sum, our results support the EMI and cumulative advantage perspectives, indicating undetected first-and second-level horizontal inequalities in Japanese education and call for similar research in other national contexts.
In this paper we consider surfaces which are critical points of the Willmore functional subject to constrained area.
In the case of small area we calculate the corrections to the intrinsic geometry induced by the ambient curvature.
These estimates together with the choice of an adapted geometric center of mass lead to refined position estimates in relation to the scalar curvature of the ambient manifold.
In the soil bacterium Pseudomonas putida, the motor torque for flagellar rotation is generated by the two stators MotAB and MotCD.
Here, we construct mutant strains in which one or both stators are knocked out and investigate their swimming motility in fluids of different viscosity and in heterogeneous structured environments (semisolid agar).
Besides phase-contrast imaging of single-cell trajectories and spreading cultures, dual-color fluorescence microscopy allows us to quantify the role of the stators in enabling P. putida's three different swimming modes, where the flagellar bundle pushes, pulls, or wraps around the cell body.
The MotAB stator is essential for swimming motility in liquids, while spreading in semisolid agar is not affected. Moreover, if the MotAB stator is knocked out, wrapped mode formation under low-viscosity conditions is strongly impaired and only partly restored for increased viscosity and in semisolid agar.
In contrast, when the MotCD stator is missing, cells are indistinguishable from the wild type in fluid experiments but spread much more slowly in semisolid agar.
Analysis of the microscopic trajectories reveals that the MotCD knockout strain forms sessile clusters, thereby reducing the number of motile cells, while the swimming speed is unaffected. Together, both stators ensure a robust wild type that swims efficiently under different environmental conditions.
IMPORTANCE
Because of its heterogeneous habitat, the soil bacterium Pseudomonas putida needs to swim efficiently under very different environmental conditions. In this paper, we knocked out the stators MotAB and MotCD to investigate their impact on the swimming motility of P. putida.
While the MotAB stator is crucial for swimming in fluids, in semisolid agar, both stators are sufficient to sustain a fast-swimming phenotype and increased frequencies of the wrapped mode, which is known to be beneficial for escaping mechanical traps. However, in contrast to the MotAB knockout, a culture of MotCD knockout cells spreads much more slowly in the agar, as it forms nonmotile clusters that reduce the number of motile cells.
Because of its heterogeneous habitat, the soil bacterium Pseudomonas putida needs to swim efficiently under very different environmental conditions. In this paper, we knocked out the stators MotAB and MotCD to investigate their impact on the swimming motility of P. putida.
As the loop space of a Riemannian manifold is infinite-dimensional, it is a non-trivial problem to make sense of the "top degree component " of a differential form on it.
In this paper, we show that a formula from finite dimensions generalizes to assign a sensible "top degree component " to certain composite forms, obtained by wedging with the exponential (in the exterior algebra) of the canonical presymplectic 2-form on the loop space.
This construction is a crucial ingredient for the definition of the supersymmetric path integral on the loop space.