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Traceable efficiency determination of large‐area perovskite on silicon tandem modules—insights from a calibration laboratories perspective
No full textAs the perovskite on silicon solar cell technology strives towards commercialization, the need to produce large-area devices increases and so does the necessity to traceably determine their efficiency. However, suitable measurement procedures and consequently efficiencies of such devices are rarely published. Due to metastability and the two-terminal tandem architecture, high demands are set on measurement procedures and the equipment used. In this publication, we present a measurement procedure which is fully built on a light emitting diode (LED)-based solar simulator. Besides power measurements, the procedure includes a full module EQE measurement, determination of temperature coefficients as well as investigations under various spectral conditions. We therefore present an approach to conduct a complete tandem module calibration using a single measurement setup by utilizing the spectral variability of the LED solar simulator. The introduced procedure is exemplarily carried out on a large-area perovskite on silicon tandem module which achieves an efficiency of 25%
Search for vector-like leptons coupling to first- and second-generation Standard Model leptons in pp collisions at [[sqrt]s] = 13 TeV with the ATLAS detector
No full textA search for pair production of vector-like leptons coupling to first- and second-generation Standard Model leptons is presented. The search is based on a dataset of proton-proton collisions at √s = 13 TeV recorded with the ATLAS detector during Run 2 of the Large Hadron Collider, corresponding to an integrated luminosity of 140 fb−1. Events are categorised depending on the flavour and multiplicity of leptons (electrons or muons), as well as on the scores of a deep neural network targeting particular signal topologies according to the decay modes of the vector-like leptons. In each of the signal regions, the scalar sum of the transverse momentum of the leptons and the missing transverse momentum is analysed. The main background processes are estimated using dedicated control regions in a simultaneous fit with the signal regions to data. No significant excess above the Standard Model background expectation is observed and limits are set at 95% confidence level on the production cross-sections of vector-like electrons and muons as a function of the vector-like lepton mass, separately for SU(2) doublet and singlet scenarios. The resulting mass lower limits are 1220 GeV (1270 GeV) and 320 GeV (400 GeV) for vector-like electrons (muons) in the doublet and singlet scenarios, respectively
Unuamitovirus fuci2 impact on Fusarium circinatum pathogenicity and pine defence response
No full textMYB68 regulates radial endodermal differentiation and suberin patterning
No full textRoots are composed of concentric layers that surround the vasculature of plants. Of these, the endodermis stands out, as it contains barriers that facilitate selective uptake. In mature root regions, endodermal cells become coated with suberin, a hydrophobic polymer that seals off the inner root parts. Intriguingly, individual endodermal cells, adjacent to the water-conducting xylem, remain unsuberized. These cells are termed “passage cells,” based on the assumption that they can facilitate vasculature access in an otherwise sealed-off area. The existence of passage cells suggests that distinct identities and cell files exist within the endodermis that may have overlooked importance. Here, we investigate this in the model plant Arabidopsis thaliana. Our work identifies a genetic regulator of cell-file-specific suberization and passage cell differentiation connected to the xylem. This provides spatiotemporal insights into the mechanism(s) underlying suberization, establishing a framework for the radial organization of the endodermis and highlighting the putative function(s) of passage cells
Gastrodin enhances stress resilience through promoting Wnt/[beta]-Catenin-dependent neurogenesis
No full textBackgroundEnhancing stress resilience constitutes a pivotal strategy in mitigating the risk of depression, making it a critical component of both prevention and treatment. In the current work, we identified a compound, gastrodin (GAS), as capable of enhancing stress resilience, as demonstrated by its ability to protect against depression following chronic stress exposure.ObjectivesTo elucidate the potential of GAS to promote neurogenesis under chronic stress, along with the associated cellular and molecular processes involved.MethodWe evaluated the effect of GAS on NSPC proliferation and differentiation using both in vitro and in vivo investigations. Neurogenesis was inhibited using temozolomide to verify GAS’s impact on stress resilience. Comprehensive methodologies, including hippocampal transcriptome analysis and western blotting, were utilized to identify the involvement of the Wnt/β-catenin pathway. Immunolocalization was conducted to confirm β-catenin’s nuclear translocation in SOX2+ cells within the hippocampal dentate gyrus subgranular zone.ResultsGAS demonstrated robust stimulation of NSPC proliferation and neuronal differentiation, enhancing adult hippocampal neurogenesis under conditions of chronic stress. Inhibition of neurogenesis negated GAS’s protective effects on stress resilience. Integrated analysis pointed to the Wnt/β-catenin signaling pathway within NSPCs as a crucial mechanism facilitating GAS-promoted neurogenesis. Inhibiting Wnt expression or blocking β-catenin’s nuclear translocation abolished GAS’s neurogenic and stress-resilience enhancing effects.ConclusionThese results suggested that GAS directly activates the Wnt/β-catenin signaling pathway, which promotes the proliferation and neuronal differentiation of NSPCs, thereby enhancing adult hippocampal neurogenesis and promoting stress resilience to mitigate the risk of depression
Validation of two plasma multimetabolite signatures for patients at risk of or with suspected pancreatic ductal adenocarcinoma (METAPAC): a prospective, multicentre, investigator-masked, enrichment design, phase 4 diagnostic study
No full textBackgroundEarlier diagnosis of pancreatic ductal adenocarcinoma is key to improving overall survival in patients with this hard-to-treat cancer. We independently validated two previously identified plasma-based metabolic signatures for exclusion of pancreatic ductal adenocarcinoma in cohorts with an increased annual risk.MethodsThe METAPAC study was a prospective, multicentre, investigator-masked, enrichment design, phase 4 trial done in 23 centres in Germany. Patients with pancreatic lesions identified by diagnostic imaging that required further diagnostic assessment were recruited and followed up for 24 months. Targeted quantitative plasma metabolite analysis was done on a liquid chromatography–tandem mass spectrometry platform. The improved metabolic (i-Metabolic) signature consisted of 12 analytes plus carbohydrate antigen (CA) 19-9, and the minimalistic metabolic (m-Metabolic) signature consisted of four analytes plus CA 19-9. The primary endpoint of the study was the exclusion of pancreatic ductal adenocarcinoma with an 85% specificity and the highest possible diagnostic accuracy. All statistical analyses were done per protocol. This study is registered with the German Clinical Trials Register (DRKS00010866).FindingsBetween Sept 9, 2016, and April 8, 2022, 1370 patients with CT-identified pancreatic lesions necessitating further diagnostic assessment were screened, of whom 1129 patients (489 with pancreatic ductal adenocarcinoma, 640 controls) were included in the primary analysis (median age 67 years [IQR 58–75]; 556 [49%] female, 572 [51%] male). The control group consisted of high-risk individuals with acute pancreatitis (11 [1%] of 1129 participants), chronic pancreatitis (113 [10%]), intraductal papillary mucinous neoplasms (232 [21%]), cystic lesions other than intraductal papillary mucinous neoplasms (271 [24%]), and metastases of extrapancreatic origin (13 [1%]). The i-Metabolic signature detected pancreatic ductal adenocarcinoma with an area under the curve (AUC) of 0·846 (95% CI 0·842–0·849), specificity of 90·4% (89·8–91·1), sensitivity of 67·5% (66·9–68·0), and balanced accuracy of 80·5% (80·2–80·8), compared with CA 19-9 alone (AUC 0·799 [0·797–0·802], pInterpretationTwo plasma-based metabolic signatures showed significant improvement in performance compared with CA 19-9 alone in excluding pancreatic ductal adenocarcinoma in a prospective real-world cohort. These findings could offer a surveillance tool in patients with an annual risk of pancreatic ductal adenocarcinoma of 1% to reduce unnecessary invasive procedures and facilitate earlier detection of resectable disease.FundingFederal Ministry of Education and Research (BMBF, Germany)
Chemoprotection and immunostimulation of alpha‐lipoic acid against chlorpyrifos‐induced toxicosis in Nile Tilapia, Oreochromis niloticus
No full textThis paper examined the chemoprotective and immunomodulatory effects of alpha-lipoic acid (ALA) against chlorpyrifos (CPL)-induced toxicosis in Nile tilapia, Oreochromis niloticus. Fish (n = 120, mean weight = 8.8 ± 0.6 g) were divided into 12 tanks (100-L capacity, 10 fish/tank) to represent two groups. Group 1 (60 fish) was fed a diet (300 g/kg crude protein) containing 40 mg ALA/kg feed, while Group 2 (60 fish) was fed a basal diet without ALA. Then, 30 fish from each group were exposed to 450 μg CPL/L. Thus, the experimental treatments were control, CPL (basal diet and exposed to CPL), ALA (ALA-based diet), and ALA + CPL (ALA-based and exposed to CPL) for 14 days. Fish fed with ALA alone showed significantly (p = 0.001) higher survival rates (100%), improved hematological and biochemical profiles, enhanced antioxidant activity, and stronger immune responses than CPL-exposed fish alone. CPL exposure caused severe physiological disorders and histological damage, particularly in the liver. However, ALA + CPL interactions mitigated these adverse effects, restoring tissue integrity and functionality. The findings underscore ALA’s potential as a dietary intervention to reduce environmental toxicant-induced stress in aquaculture, improving fish health and resilience against toxins
