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Chemical evolution models predict a gradual build-up of 13C in the Universe, based on empirical nuclear reaction rates and assumptions on the properties of stellar populations. However, old metal-poor stars within the Galaxy contain more 13C than is predicted, suggesting that further refinements to the models are necessary. Gas at high-redshift provides important supplementary information at metallicities |$-2\lesssim \left[{\rm Fe/H}\right]\lesssim -1$|⁠ , for which there are only a few measurements in the Galaxy. We obtained new, high-quality, VLT/ESPRESSO observations of the QSO B1331 |$+$| 170 and used them to measure 12C/13C in the damped Lyman- |$\alpha$| system (DLA) at |$z_{\rm abs}=1.776$|⁠ , with |$\left[{\rm Fe/H}\right]$| = −1.27. ai-vpfit , an artificial intelligence tool based on genetic algorithms and guided by a spectroscopic information criterion, was used to explore different possible kinematic structures of the carbon gas. Three hundred independent ai-vpfit models of the absorption system were produced using pre-set 12C/13C values, ranging from 4 to 500. Our results show that |${\rm ^{12}C / ^{13}C}=28.5^{+51.5}_{-10.4}$|⁠ , suggesting a possibility of 13C production at low metallicity. [ABSTRACT FROM AUTHOR]

Astronomical precision spectroscopy underpins searches for life beyond Earth, direct observation of the expanding Universe and constraining the potential variability of physical constants on cosmological scales. Laser frequency combs can provide the required accurate and precise calibration to the astronomical spectrographs. For cosmological studies, extending the calibration with such astrocombs to the ultraviolet spectral range is desirable, however, strong material dispersion and large spectral separation from the established infrared laser oscillators have made this challenging. Here, we demonstrate astronomical spectrograph calibration with an astrocomb in the ultraviolet spectral range below 400 nm. This is accomplished via chip-integrated highly nonlinear photonics in periodically-poled, nano-fabricated lithium niobate waveguides in conjunction with a robust infrared electro-optic comb generator, as well as a chip-integrated microresonator comb. These results demonstrate a viable route towards astronomical precision spectroscopy in the ultraviolet and could contribute to unlock the full potential of next-generation ground-based and future space-based instruments. Here the authors demonstrate ultraviolet astronomical frequency combs, derived from the near-infrared domain via efficient harmonic generation in nanophotonic waveguides, to provide precision calibration to astronomical spectrographs for exoplanet science and precision cosmology. [ABSTRACT FROM AUTHOR]

Coevolution is often found in parasite–host interactions, but has not yet been described for hemiparasitic plants and their hosts. Root hemiparasites like Rhinanthus alectorolophus perform photosynthesis but also parasitize other plant species, some of which (e.g. Plantago lanceolata) may defend themselves against parasite attack by blocking the haustoria of the parasites. We grew seedlings of the hemiparasite R. alectorolophus and the potential host P. lanceolata from seven grassland sites in a factorial design. To detect differences in host defence, we also included hosts from two 'naïve' populations from regions where the parasite does not occur. R. alectorolophus grew consistently larger and had higher fitness with sympatric than with allopatric hosts, suggesting parasite adaptation to local host populations. Moreover, R. alectorolophus remained smallest with allopatric hosts from the same region and reached intermediate sizes with allopatric hosts from other regions or naïve hosts, suggesting host adaptation to parasites at the regional scale. Parasite presence reduced the size of the host plants already after four weeks, but only that of hosts with 'experience' of the parasite, suggesting an early host response. Follow‐up experiments confirmed that parasites attach to hosts already after four weeks and hosts respond by changing belowground allocation patterns. However, parasite roots did not preferentially grow towards sympatric hosts. Our results suggest that local adaptation to hosts can occur even in generalist parasites and does not require specialization on individual hosts. We discuss the role of potential mechanisms, including variation in chemical signalling (early) and in host defence (late effects). [ABSTRACT FROM AUTHOR]

Employee job satisfaction is an important attitudinal variable for many reasons, and due to the current shortage of workers, it may be even more critical in today's workplace. Job satisfaction is one of the most studied variables in the organizational behavior literature, mainly because researchers understand its impact on employee turnover and organizational effectiveness. The perception of workplace politics impacts job satisfaction. Most of the past research in the organizational behavior literature has found that employees generally perceive workplace politics negatively. However, there are differences in how employees view and react to organizational politics that are, at least partly, based on individual differences. The purpose of this study is to investigate the moderating effects of employee gender and age on the perceptions of organizational politics-job satisfaction relationship. A primary objective of this study is to provide further clarity on the effect of perceptions of politics in work reward decisions on specific job satisfaction facets for different age and gender groups. This study reports findings from a diverse group of 601 employees employed in more than a dozen organizations representing both the service and manufacturing sectors. We use hierarchical moderated regression analysis to test the study hypotheses to control for spurious variable contamination and isolate the study's main effects. The results support the hypothesis that employee perceptions of organizational politics have a different impact on job satisfaction for different gender and age groups. More specifically, results suggest that older employees are likely to be more negatively affected by perceptions of organizational politics than younger employees. Additionally, this study supports the notion that political decisions affect the job satisfaction of female employees more negatively than male employees in certain circumstances. [ABSTRACT FROM AUTHOR]

Geometric morphometrics (GMM) have been applied to understand morphological variation in biological structures. However, research studying cortical bone through geometric histomorphometrics (GHMM) is scarce. This research aims to develop a landmark‐based GHMM protocol to depict osteonal shape variation in the femoral diaphysis, exploring the role of age and biomechanics in bone microstructure. Proximal, midshaft, and distal anatomical segments from the femoral diaphysis of six individuals were assessed, with 864 secondary intact osteons from eight periosteal sampling areas being manually landmarked. Observer error was tested using Procrustes ANOVA. Average osteonal shape and anatomical segment‐specific variation were explored using principal component analysis. Osteon shape differences between segments were examined using canonical variate analysis (CVA). Sex differences were assessed through Procrustes ANOVA and discriminant function analysis (DFA). The impact of osteonal size on osteonal shape was investigated. High repeatability and reproducibility in osteon shape landmarking were reported. The average osteon shape captured was an elliptical structure, with PC1 reflecting more circular osteons. Significant differences in osteon shape were observed between proximal and distal segments according to CVA. Osteon shape differed between males and females, with DFA showing 52% cross‐validation accuracies. No effect of size on shape was reported. Osteonal shape variation observed in this study might be explained by the elderly nature of the sample as well as biomechanical and physiological mechanisms playing different roles along the femoral diaphysis. Although a larger sample is needed to corroborate these findings, this study contributes to the best of our knowledge on human microanatomy, proposing a novel GHMM approach. [ABSTRACT FROM AUTHOR]

The influence of pulping variables on the pulp and black liquor properties for a neutral sulphite semi-chemical pulping system was investigated in a pilot plant pulping setup situated at an industrial paper mill. Eucalyptus chips were used as raw material and the operating variables were Na2SO3 charge (8–18% w/w on oven-dry wood), Na2CO3 charge (0.5–3.0% w/w on oven-dry wood) and maximum cooking temperature (160–180 °C). Response surface methodology was used to parametrize empirical models to find the optimal conditions for maximizing the short-span compression strength index of the pulp. The derived regression models for the black liquor properties and the pulp hypo number had R2-adjusted values above 0.8 and p-values for overall significance below 0.05. The derived regression models for the handsheet strength properties had R2-adjusted values between 0.3 and 0.45 and p-values for overall significance either below 0.05 or between 0.05 and 0.1. The sulphite charge, followed by the carbonate charge, had the most notable effect on the evaluated properties with the effects of temperature being less significant. Optimization of the pilot plant system showed that the short-span compression strength index of the pulp could be maximized to 26.7 N m/g, using a sulphite charge of 9.4% (w/w on oven-dry wood) and a carbonate charge of 1.94% (w/w on oven-dry wood), similar to short-span compression strength indices typically achieved using other pulping processes. [ABSTRACT FROM AUTHOR]

Background: Ex vivo normothermic machine perfusion (NMP) is a promising tool for assessing an isolated kidney prior to transplantation. However, there is no consensus on the perfusate's optimal oxygen‐carrying capacity to support renal function. To investigate the association of hemoglobin levels with renal function parameters, a retrospective analysis of isolated, normothermically, perfused porcine kidneys was performed. Methods: Between 2015 and 2021, a total of 228 kidneys underwent 4 h of NMP with perfusates that varied in hemoglobin levels. A generalized linear model was used to determine the association of hemoglobin levels with time‐weighted means of renal function markers, such as fractional sodium excretion (FENa) and creatinine clearance (CrCl). Stratified by baseline hemoglobin level (<4.5, 4.5–6, or >6 mmol/L), these markers were modeled over time using a generalized linear mixed‐effects model. All models were adjusted for potential confounders. Results: Until a hemoglobin level of around 5 mmol/L was reached, increasing hemoglobin levels were associated with superior FENa and CrCl. Thereafter, this association plateaued. When hemoglobin levels were categorized, hemoglobin <4.5 mmol/L was associated with worse renal function. Hemoglobin levels were neither significantly associated with proteinuria during NMP nor with ATP levels at the end of NMP. Hemoglobin levels >6 mmol/L showed no additional benefits in renal function. Conclusion: In conclusion, we found an association between baseline hemoglobin levels and superior renal function parameters, but not injury, during NMP of porcine kidneys. Furthermore, we show that performing a retrospective cohort study of preclinical data is feasible and able to answer additional questions, reducing the potential use of laboratory animals. [ABSTRACT FROM AUTHOR]

Ground-based astronomy is unavoidably subject to the adverse effect of atmospheric turbulence, a.k.a. the seeing, which blurs the images and limits the achievable spatial resolution. For spectroscopic observations, it leads to slit or fibre-injection losses, since not all photons distributed over the extended seeing disc can be captured. These losses might have a very substantial impact on the overall efficiency of a spectrograph and are naturally highly variable. Assessing the fibre-injection losses requires accurate information about the image quality (IQ) delivered by the telescope to the instrument over the course of the observations, which, however, is often not directly available. ESPRESSO provides acquisition and field-stabilization images attached to the science data and thus offers the opportunity for a post-processing analysis. Here, we present a novel method to infer the IQ profile and fibre-injection losses from the integrated field-stabilization images, utilizing the spill-over light that does not get injected into the fibre. We validate these measurements against the IQ observed in the acquisition images and determine that our method delivers unbiased estimates with a scatter of 0.11 arcsec for the FWHM of the profile and |$15~{{\ \rm per\ cent}}$| in terms of fibre-injection losses. This compares favourably to the estimates derived from either the differential image motion monitor or the telescope guide probe sensors and therefore represents a valuable tool to characterize the instrument efficiency and to correct raw spectra for fibre-injection losses. [ABSTRACT FROM AUTHOR]

Hand-held devices have revolutionized communication and education in the last decade. Consequently, mobile learning (m-learning) has become popular among medical students. Nevertheless, there are relatively few studies assessing students' learning outcomes using m-learning devices. This observational study presents an anatomy m-learning tool ("eMed"-App), an application developed to accompany an anatomy seminar and support medical students' self-directed learning of the skeletal system. Questionnaire data describe where, how frequently, and why students used the app. Multiple choice examination results were analyzed to evaluate whether usage of the app had an effect on test scores. The "eMed"-App application was used by 77.5% of the students, mainly accessed by Android smartphones, and at students' homes (62.2%) in order to prepare themselves for seminar sessions (60.8%), or to review learning content (67%). Most commonly, students logged on for less than 15 minutes each time (67.8%). Frequent app users showed better test results on items covering "eMed"-App learning content. In addition, users also achieved better results on items that were not related to the content of the app and, thus, gained better overall test results and lower failure rates. The top quartile of test performers used the "eMed"-App more frequently compared to students in lower quartiles. This study demonstrated that many students, especially the high-performing ones, made use of the "eMed"-App. However, the app itself did not result in better outcomes, suggesting that top students might have been more motivated to use the app than students who were generally weak in anatomy.

The He ii transverse proximity effect - enhanced He ii Lyα transmission in a background sightline caused by the ionizing radiation of a foreground quasar - offers a unique opportunity to probe the emission properties of quasars, in particular the emission geometry (obscuration, beaming) and the quasar lifetime. Building on the foreground quasar survey published in Schmidt et al., we present a detailed model of the He ii transverse proximity effect, specifically designed to include light travel time effects, finite quasar ages, and quasar obscuration. We post-process outputs from a cosmological hydrodynamical simulation with a fluctuating He ii ultraviolet background model, with the added effect of the radiation from a single bright foreground quasar. We vary the age t age and obscured sky fractions Ωobsc of the foreground quasar, and explore the resulting effect on the He ii transverse proximity effect signal. Fluctuations in intergalactic medium density and the ultraviolet background, as well as the unknown orientation of the foreground quasar, result in a large variance of the He ii Lyα transmission along the background sightline. We develop a fully Bayesian statistical formalism to compare far-ultraviolet He ii Lyα transmission spectra of the background quasars to our models, and extract joint constraints on t age and Ωobsc for the six Schmidt et al. foreground quasars with the highest implied He ii photoionization rates. Our analysis suggests a bimodal distribution of quasar emission properties, whereby one foreground quasar, associated with a strong He ii transmission spike, is relatively old (22 Myr) and unobscured (), whereas three others are either younger than 10 Myr or highly obscured ().

Recent studies have shown that a subset of nucleoporins (Nups) can detach from the nuclear pore complex and move into the nuclear interior to regulate transcription. One such dynamic Nup, called Nup98, has been implicated in gene activation in healthy cells and has been shown to drive leukemogenesis when mutated in patients with acute myeloid leukemia (AML). Here we show that in hematopoietic cells, Nup98 binds predominantly to transcription start sites to recruit the Wdr82-Set1A/COMPASS (complex of proteins associated with Set1) complex, which is required for deposition of the histone 3 Lys4 trimethyl (H3K4me3)-activating mark. Depletion of Nup98 or Wdr82 abolishes Set1A recruitment to chromatin and subsequently ablates H3K4me3 at adjacent promoters. Furthermore, expression of a Nup98 fusion protein implicated in aggressive AML causes mislocalization of H3K4me3 at abnormal regions and up-regulation of associated genes. Our findings establish a function of Nup98 in hematopoietic gene activation and provide mechanistic insight into which Nup98 leukemic fusion proteins promote AML.

Migraine is a recurrent pain condition traditionally viewed as a neurovascular disorder, but little is known of its vascular basis. In epidemiological studies migraine is associated with an increased risk of cardiovascular disease, including coronary artery disease (CAD), suggesting shared pathogenic mechanisms. This study aimed to determine the genetic overlap between migraine and CAD, and to identify shared genetic risk loci, utilizing a conditional false discovery rate approach and data from two large-scale genome-wide association studies (GWAS) of CAD (C4D, 15,420 cases, 15,062 controls; CARDIoGRAM, 22,233 cases, 64,762 controls) and one of migraine (22,120 cases, 91,284 controls). We found significant enrichment of genetic variants associated with CAD as a function of their association with migraine, which was replicated across two independent CAD GWAS studies. One shared risk locus in the PHACTR1 gene (conjunctional false discovery rate for index SNP rs9349379 < 3.90 x 10-5), which was also identified in previous studies, explained much of the enrichment. Two further loci (in KCNK5 and AS3MT) showed evidence for shared risk (conjunctional false discovery rate < 0.05). The index SNPs at two of the three loci had opposite effect directions in migraine and CAD. Our results confirm previous reports that migraine and CAD share genetic risk loci in excess of what would be expected by chance, and highlight one shared risk locus in PHACTR1. Understanding the biological mechanisms underpinning this shared risk is likely to improve our understanding of both disorders.

We report on a target system supporting automated positioning of nano-targets with a precision resolution of in three dimensions. It relies on a confocal distance sensor and a microscope. The system has been commissioned to position nanometer targets with 1Â Hz repetition rate. Integrating our prototype into the table-top ATLAS 300 TW-laser system at the Laboratory for Extreme Photonics in Garching, we demonstrate the operation of a 0.5Â Hz laser-driven proton source with a shot-to-shot variation of the maximum energy about 27% for a level of confidence of 0.95. The reason of laser shooting experiments operated at 0.5Â Hz rather than 1Â Hz is because the synchronization between the nano-foil target positioning system and the laser trigger needs to improve.