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Morphological map of the northern delta in Jezero crater, Mars
No full textThe dataset contains the morphological map of the northern delta in Jezero crater on Mars in ArcGIS mapfile (.mapx) format, or (in case ArcGIS is not available) as separate shapefiles (then without layer styling). The mapping was done in ArcGIS Pro 3.5.1 using HiRISE Jezero Northern Delta mosaic (DOI: 10.17169/refubium-51196), created from HiRISE data (High Resolution Imaging Science Experiment, McEwen et al., 2007, DOI: 10.1016/j.icarus.2023.115795). The mapping was done at the digitalization scale 1:10000
The annual variation of the M2 gravimetric tidal parameters investigated with nonlinear, time-stepping ocean models
No full textTemporal variations of the M2 tidal parameters in gravity are observed at all superconducting gravimeter stations. We specifically investigate the annual variation of M2 tidal parameters. A similar variation is observed for the parameters from sea surface heights which is larger than expected from astronomical forcing alone. This leads to the hypothesis that the variations of the gravimetric tidal parameters are caused by the loading of the annual variation of M2 in the oceans. Only nonlinear, time-stepping ocean models are able to describe such variations. We use sea surface heights from three global and two regional models of this kind to calculate the loading. The loading time series is then added to synthetic body tides and analyzed by a moving window tidal analysis with ETERNA in the same way as the measured data. We compare the resulting variations of the M2 tidal parameters for synthetic gravity with those observed from measurements. Three of the five ocean models show an annual variation of a similar order of magnitude which supports our hypothesis. The other two ocean models produce smaller or no clear annual variation of the M2 tidal parameters. In the ocean the annual variation of M2 has large amplitudes in shelf areas and small amplitudes in the open ocean. Large areas with small amplitude might contribute to the gravity loading as much as small areas with large amplitudes do. We investigate this with the global Hycom model at three SG stations. The investigation shows that not only close shelf areas but also distant ocean regions, including open ocean areas, contribute significantly to the annual variation of the M2 tidal parameters at the superconducting gravimeter stations
Genetic Encoding of Pentafluorophosphato-Phenylalanine Provides PF5-Proteins as Phosphoprotein Mimetics
No full textProtein phosphorylation is one of the most important posttranslational modifications altering the structure, stability, and activity of more than 13 000 human proteins. In this work, the phosphotyrosine mimetic pentafluorophosphato-difluoromethyl-phenylalanine (PF5CF2Phe) was genetically encoded and incorporated into three different proteins. Screening two libraries of orthogonal aminoacyl-tRNA synthetases identified enzymes enabling the efficient and specific incorporation of PF5CF2Phe into red fluorescent protein (RFP) via amber stop codon suppression. Two model proteins, human ubiquitin (Ubq) and the B1 immunoglobulin-binding domain of streptococcal protein G (GB1), were prepared with PF5CF2Phe mutations and investigated for potential interaction partners. While native GB1 showed no binding to protein tyrosine phosphatases (PTP), PF5-GB1, with PF5CF2Phe at position 17, was a strong inhibitor of the phosphatases PTP1B and SHP2. PF5-Ubq was produced and converted into the first example of a protein carrying the most prominent phosphotyrosine mimetic, phosphono-difluoromethyl phenylalanine (PO3CF2Phe). With increasing need in the biosciences to delineate the functions of complex phosphorylation patterns, genetic encoding of PF5CF2Phe yielding phosphoprotein mimetics opens unique opportunities for precise functional studies where site-specific and homogeneous protein modifications are required
The mechanisms of forced military enlistment amid the intersections of ethnicity, rurality and spatial mobility in Russia
No full textThis paper is focused on the forced mechanisms of military enlistment for participation in Russia’s war in Ukraine. It argues that the structures of spatial mobility determine the greater vulnerability of rural dwellers and other lower strata of the population to coercive military enlistment by the state. It also argues that multi-dimensional barriers to spatial mobility contribute to the intersectional vulnerability when, for example, being an ethnic minority also often overlaps with being a rural resident, which in turn results in fewer opportunities to avoid military conscription. The author’s attention to broader social forces shows that the decision to sign a military contract during wartime is often a forced measure. Combining digital ethnography, expert interviews, regression analysis and autoethnography she explains how the intersections of several forms of inequalities contribute to vulnerability to the forced military enlistment
Crystal structure of Cu2Zn(GexSi1−x)Se4 solid solution: the kesterite to wurtz–kesterite structural phase transition
No full textDeveloping low-cost, sustainable, and environmentally friendly top absorber layers for tandem solar cells is essential to advancing photovoltaic technologies and accelerating the transition to renewable energy. In this work, we explore the potential of tetravalent (Cu2Zn(GexSi1−x)Se4) cation mutations in chalcogenide compound semiconductors with the aim of finding a material with increased band gap and reduced structural disorder. A combination of high-resolution synchrotron powder diffraction and neutron powder diffraction was used to determine the atomic positions and monoclinic angles in monoclinic wurtz–kesterite type Cu2Zn(GexSi1−x)Se4 mixed crystals as well as to determine the cation distribution in the crystal structure of Ge-rich kesterite-type and Si-rich wurtz–kesterite type mixed crystals. These investigations enabled us to deduce the structural transition scenario within the Cu2Zn(GexSi1−x)Se4 series. The transition occurs via a region where two phases with different crystal structures, tetragonal and monoclinic and thus a different distortion of the coordination tetrahedra, but the same cation distribution within the element specific cation sites co-exist. Thus, the structural transition between the kesterite and the wurtz–kesterite structure within the Cu2Zn(GexSi1−x)Se4 series is a distortion driven transition. The study identifies cation mutation in quaternary chalcogenides as a promising strategy beyond chalcopyrites and kesterites for low cost and environmentally friendly top absorbers in tandem solar cells
Role of the transmembrane domain in severe acute respiratory syndrome (SARS) coronavirus 2 spike for palmitoylation and membrane fusion
No full textPalmitoylation is a reversible post-translational modification that enhances protein hydrophobicity and regulates cellular functions such as trafficking and signaling. In humans, this modification is catalyzed by 23 DHHC enzymes, but the mechanisms by which they recognize their substrates remain unclear. The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein undergoes palmitoylation primarily by DHHC20 with subsequent modification by DHHC9 at 10 cytoplasmic tail (CT) cysteines, a modification crucial for membrane fusion and viral entry. Using AlphaFold2 modeling and site-directed mutagenesis, we identified three key components critical for efficient spike palmitoylation: (i) Lys1211 at the ectodomain–transmembrane domain (TMD) interface, likely facilitating electrostatic interactions with DHHC20's acidic residues; (ii) a stable trimeric TMD helix, where mutations at the trimer interface impair palmitoylation, in contrast to changes in outward-facing residues; and (iii) a conserved hydrophilic motif in the CT, located between acylated cysteine clusters, likely promoting optimal substrate positioning near DHHC20's catalytic site. Co-immunoprecipitation assays revealed that mutations in these residues disrupt spike-DHHC20 interactions, while leaving spike–DHHC9 binding unchanged, suggesting that they affect enzyme-substrate complex formation. Fusion assays revealed nuanced effects; while palmitoylation generally correlated positively with membrane fusion, certain exceptions highlighted the complex relationship between these processes. Mutations in the CT markedly reduce total spike palmitoylation but only modestly affect cell–cell fusion. Some substitutions in the TMD impair fusion with little change in overall acylation. Our findings elucidate the structural and biophysical determinants of spike palmitoylation and its distinct roles in membrane fusion, offering insights into SARS-CoV-2 pathogenesis and potential antiviral targets
Recognizing stressed chicken signs: A comparison using the Happy Chicken Tool and the Stressed Chicken Scale
No full textThis study investigates the use of deep learning, specifically convolutional neural networks (CNNs), and transfer learning for detecting signs of discomfort in chickens through image analysis.
We present a comprehensive framework that includes data preparation, model training, and evaluation using transfer learning with pre-trained CNN models such as EfficientNet and MobileNet. The methodology includes image extraction from video footage, followed by preprocessing, and augmentation to improve dataset diversity and robustness.
Model performance was evaluated using cross-validation on the original dataset and validation on two separate datasets, with metrics such as accuracy, sensitivity, and specificity. Results of the CNNs were compared to human observers' stress ratings on the same datasets (= images) of chickens using the Stressed Chicken Scale.
We found that AI can detect discomfort in individual chickens in side-view images, comparable to humans. Our findings show that certain CNN models, in particular variants of EfficientNet, show high performance in identifying stress signs in chickens. These results highlight the potential of deep learning for automated animal welfare monitoring.
To enhance model interpretability, we used a Grad-CAM, which provides valuable insights into the decision-making process of the models. We found that the AI “looks” at specific body parts of the chickens when making decisions.
This research contributes to the development of innovative, non-invasive methods for monitoring chicken welfare, and may provide the foundation for a useful tool for early detection of stress and discomfort indicators in chickens at individual animal level
Genotypische und Phänotypische Charakterisierung von Nahrungsmittelallergien und mögliche Strategien in der Diagnostik und Prävention
No full textNahrungsmittelallergien zählen zu den häufigsten chronischen Erkrankungen im Kindesalter, wobei persistierende Formen lebenslang den Alltag der Betroffenen prägen. Ziel dieser Arbeit war es daher, prädiktive Faktoren und Verfahren zur frühzeitigen Diagnostik zu identifizieren, um wirksam und gezielt individualisierte Präventions- und Therapieansätze entwickeln zu können. So wurden in dieser Arbeit genetische Faktoren für die Entwicklung von Nahrungsmittelallergien identifiziert und bezüglich ihrer phänotypischen Auswirkungen auf die mögliche Reaktionsschwere und den Krankheitsverlauf näher charakterisiert. Auf Basis dieser Erkenntnisse, die in Einklang mit der dualen Allergenhypothese zur Entwicklung von Sensibilisierung und Nahrungsmittelallergien stehen, wurde der Präventionsansatz der frühen Einführung von pasteurisiertem Hühnerei in der Allgemeinbevölkerung untersucht, wobei kein präventiver Effekt dargestellt werden konnte. Darüber hinaus wurde die Haltung in der Bevölkerung gegenüber der Prämastikation untersucht, wobei dargestellt werden konnte, dass diese Fütterungsmethode als potentielle Möglichkeit zur Allergieprävention von einem beträchtlichen Anteil der Befragten wahrgenommen wird. Neben adäquaten Maßnahmen zur Primärprävention ist eine frühzeitige Diagnostik von Nahrungsmittelallergien zur Sekundärprävention essentiell. Bislang ist hierfür oftmals eine orale Provokationstestung nötig, die sowohl zeit- als auch kostenintensiv ist und mit einem Anaphylaxierisiko einhergeht. Bezüglich der Diagnostik von Haselnuss- und Erdnussallergien, konnte in dieser Arbeit gezeigt werden, dass die Berechnung des Verhältnisses von Komponenten-spezifischem zu Gesamt-IgE keine höhere diagnostische Treffsicherheit als die alleinige Bestimmung von spezifischem IgE gegenüber Ara h2 und Cor a14, in unserer Population von Kindern mit Verdacht auf eine Erdnuss- oder Haselnussallergie, aufweist. Neben einer akkuraten Diagnostik ist für das Management von Nahrungsmittelallergien auch eine genaue phänotypische Beschreibung des Krankheitsbildes wichtig, um klinische Anzeichen frühzeitig erkennen und einordnen zu können. In einer Studie an nahrungsmittelallergischen Kindern wurde daher das bis dato nur in einzelnen Fallberichten dargestellte Symptom des imperativen Schlafzwangs systematisch charakterisiert. Zusammenfassend konnte in dieser Arbeit gezeigt werden, dass die Untersuchung genetischer Faktoren, präventiver Strategien und moderner diagnostischer Ansätze einen relevanten Beitrag zum besseren Verständnis und zur klinischen Charakterisierung von Nahrungsmittelallergien im Kindesalter liefert
HARPS-N, TESS, and CHEOPS* discover a transiting sub-Neptune and two outer companions around the bright solar analogue HD 85426
No full textWe provide a detailed characterization of the planetary system orbiting HD 85426 (TOI-1774). This bright G-type star ( M∗: 0.99 M ; R∗: 1.13R ; age: 7.4 Gyr; V mag: 8.25) hosts a transiting sub-Neptune, HD 85426 b, with an orbital period of 16.71 d and a blackbody equilibrium temperature of 824+ 11 −11 K. By jointly analysing HARPS-N RVs, TESS , and CHEOPS photometric data and using two different stellar activity mitigation techniques, we constrain planet b’s mass to 6 . 0+ 1 . 5 −1 . 6 M ⊕and 8 . 5+ 1 . 3 −1 . 4 M ⊕, depending on the mitigation technique. We investigate the dependence of these results on the priors, data selection, and inclusion of other Keplerians in the modelling. Using this approach, we identify the presence of two non-transiting planetary companions with minimum masses near 10M ⊕and orbital periods of 35.7 and 89 d. Additionally, we reject the initial hypothesis that the 35.7-d periodic signal was due to stellar activity. We also determine HD 85426 b’s radius to be 2 . 78+ 0 . 05 −0 . 04 R ⊕and compute a transmission spectroscopy metric in the range of 82 to 115, making this planet a highly valuable target for atmospheric characterization
Suzetrigine, a NaV1.8 Inhibitor as a Novel Approach for Pain Therapy—A Medicinal and Chemical Drug Profile
No full textSuzetrigine was approved by the US American Food and Drug Administration in 2025 as the first oral, non-opioid, selective inhibitor of NaV1.8 sodium channel for the treatment of acute pain. Therefore, it represents a groundbreaking advancement in pain management. This review aims to provide an overview of the milestones in the medicinal-chemical development of NaV1.8 inhibitors, eventually leading to suzetrigine. The multi-step synthesis route of suzetrigine is presented. Taking structural features into account, insights are provided into what plays a role for the inhibition of the NaV1.8 channel. In addition, pharmacodynamic and pharmacokinetic aspects of the new drug, such as bioavailability, metabolism, and interaction with CYP450 enzymes, are discussed. A summary based on a large number of clinical trials demonstrating remarkable efficacy completes this comprehensive drug profile of suzetrigine, while also addressing limitations of the clinical trials and suggesting future perspectives