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Gas–Solid Reaction to Rapidly Construct Chiral MOFs for Efficient Enantioselective Sensing
Across-cities transportable 13C hyperpolarization using UV-induced labile radicals
Abstract Hyperpolarized 13 C Magnetic Resonance Spectroscopic Imaging (HP 13 C-MRSI) has the potential to transform diagnostic radiology thanks to its unique ability to noninvasively detect a broad range of diseases entailing aberrant metabolism. However, clinical adoption has been hindered by the short lifetime of 13 C-hyperpolarization and the resulting need for on-site polarizer near the MR scanner. In this work, we present a solution for long-lived transportable HP molecular contrast agents that uses dissolution Dynamic Nuclear Polarization (dDNP) combined with UV-induced labile radicals. This approach allows centralized pre-polarization and transport under hours-long storage T 1 conditions. We validate this concept through the first across-cities HP 13 C-MRSI experiments in vivo, injecting healthy female rats with both a perfusion/angiography ([1- 13 C]HP001) and a metabolic ([U- 13 C, d 7 ]glucose) contrast agent. Our findings advance the feasibility of decentralized, scalable HP MRI workflows, removing the barrier of on-site infrastructure.
Modeling wave scattering in impedance-lined duct networks with expansion chambers
This article presents a general framework for predicting acoustic wave scattering in ducted systems with expansion chambers and dissipative linings, as commonly encountered in engineering noise-control devices. The method represents the acoustic field in each duct segment through orthogonal modal expansions consistent with the local boundary conditions and enforces continuity conditions at the interfaces to determine the reflected and transmitted wave content. Model verification is carried out using representative benchmark configurations excited by a piston-type source. The results show that acoustic linings substantially impact propagation and resonance behavior through changes in modal wavenumbers and coupling between modes. Parametric comparisons between single- and double-lined expansion chamber designs demonstrate that introducing an additional lined cavity strengthens modal interactions, shifts resonance features, and improves attenuation over a broader frequency range. The proposed formulation is computationally efficient, physically interpretable, and readily adaptable to practical duct geometries and lining specifications, making it suitable for the design and optimization of waveguide-based noise mitigation components in applications such as HVAC networks, exhaust systems, and aero-engine ducting.
Lanthanide Tri-Doping Engineered Upconversion Emissions under Dual-Wavelength Excitation toward High-Resolution Imaging
An anti-adhesive compound modulating the production of Staphylococcus aureus cell wall-anchored proteins
Unusual outcome variances as a method to identify potentially problematic clinical trials
An unusual outcome variance contributed to uncovering major cases of research misconduct, leading to over 200 retractions. Detecting such problematic randomized trials early – before they unduly influence clinical guidelines – remains challenging. Empirical evidence indicates that differences in variances between trial arms (DiVBTAs) are usually small and non-significant in properly conducted trials. This study investigated whether the converse – unusually large and statistically significant DiVBTAs - can serve as a red flag for potentially problematic trials. We conducted simulations to assess the sensitivity and specificity of a DiVBTA-based decision rule under realistic scenarios, including proper randomization, heterogeneous treatment effects, and missing-not-at-random data. In parallel, we applied the rule in a real-world analysis of 226 systematically sampled randomized trials in diabetes research to assess whether unusually large and statistically significant DiVBTAs occur with sufficient frequency to warrant screening. Unusually large DiVBTA values were defined as those falling outside the 3-sigma prediction limits. Simulations demonstrated high specificity, with legitimate trials rarely flagged (low false-positive rate), and adequate sensitivity for detecting a specific form of severe fabrication. In the empirical analysis, 19 out of 226 trials (8%) were flagged as potentially problematic demonstrating utility to screening trials for unusually large and statistically significant DiVBTAs. Subsequent screening of the identified trials revealed additional concerns in 18 (out of 19) flagged trials. These findings suggest that screening for unusually large, statistically significant DiVBTAs offers a simple, low-effort tool to identify trials warranting further scrutiny, potentially strengthening the reliability of evidence used in clinical guidelines.
Exceptionally Fast Heterogeneous Catalysis Using Perovskite Nanocrystals for Hydrocarbon Aromatization
Comparison and optimization of cellular neighbor preference methods for quantitative tissue analysis
Abstract Studying the spatial distribution of cell types in tissues is essential for understanding their function in health and disease. A widely applied measure in spatial omics analysis is the pairwise neighbor preference of cell types, indicating whether two cell types frequently occur in close proximity to each other. While various neighbor preference methods exist, there is no clear guidance for selecting one over another. Here we present a comprehensive comparison of existing neighbor preference analysis methods. We systematically evaluate the method’s underlying analytical steps and introduce COZI, a combination of analysis steps not previously described. We compare results from existing methods and COZI with respect to their ability to distinguish distinct tissue architectures and to recover neighbor preference directionality using two tissue simulations and two biological datasets. Overall, we delineate method-specific strengths and limitations and demonstrate that COZI provides sensitive and directional neighbor preference analysis for quantification of spatial data.
Is early childhood education associated with better midlife cognition, especially for children facing socioeconomic marginalization?
Purpose Education is a strong predictor of cognitive aging, but little work has evaluated the relationship between early childhood education (ECE) specifically and cognition in midlife and beyond. Methods Using data from the National Longitudinal Survey of Youth 1979 Cohort (n = 7,129), we examined the relationship between attending preschool, Head Start (federally-funded free ECE targeted for low-income families), or no ECE, and midlife global cognition. We defined midlife global cognition based on immediate and delayed word recall, serial 7 subtraction, and backwards counting. We used multivariable linear regression models to estimate overall associations and associations among groups more likely eligible for Head Start, and to evaluate heterogeneities by sex, race and ethnicity, and family socioeconomic status (SES). Results Overall, preschool, but not Head Start, was associated with better midlife cognition compared to no ECE in some models. Among families more likely eligible for Head Start, we found not only that preschool (β = 0.26; 95% CI: 0.01, 0.51) was associated with better midlife cognition, but also directionally positive evidence that Head Start (β = 0.09; 95% CI: −0.08, 0.27) was associated with better midlife cognition. Associations varied; Head Start was associated with higher midlife cognition for Black and Hispanic men and people with higher family SES marginalization compared to other groups. Conclusions This study provides initial evidence suggesting that early childhood education may be associated with better cognition more than 40 years later, especially for Black and Hispanic men and people who faced greater socioeconomic marginalization.
Topology-Encoded Asymmetric Tandem Catalysis in BINAP-Based Metal–Organic Frameworks
Discovery of confined two-dimensional Laves tiling in a magnesium alloy
Abstract Laves phases composed of two-dimensional (2D) Laves tilings are prevalent in condensed matter systems, yet the existence of these 2D tilings as isolated structural motifs has remained unverified. Here, we report the discovery of a metastable, confined 2D Laves tiling precipitate in a compositionally dilute Mg alloy, revealed through aberration-corrected high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) in combination with atomic-resolution energy-dispersive X-ray spectroscopy (EDS) mapping. The structure adopts a Laves-type Al 2 Ca configuration confined to the (0001) basal plane of the Mg matrix, with a thickness of merely a single tiling layer (~4.62 Å), stabilized by adjacent Mg/Ca interfacial atomic layers. Theoretical calculations reveal that tensile strain in the surrounding matrix suppresses the diffusion of small-sized Al solutes, thereby inhibiting out-of-plane coarsening. Notably, prolonged thermal exposure leads to the formation of multi-configurational layered Laves structures assembled from these fundamental units. These findings elucidate the precipitation behavior in Mg–Al–Ca alloys and uncover a structurally confined Laves tiling motif, advancing our understanding of Laves phase formation and solute clustering in metallic systems.
The neuroactive potential of the elderly human gut microbiome is associated with mental health status
Ageing is usually associated with physiological decline, increased mental health issues, and cognitive. deterioration, alongside specific changes in the gut microbiome. However, the relationship between the neuroactive potential of the gut microbiome and mental health and cognition among the elderly remains less explored. This study examines a cohort of 153 older Chilean adults with cognitive complaints, assessing anthropometric data, mental health via five distinct tests, and gut microbiome composition through 16SV4 sequencing. Our findings reveal associations between anthropometric factors and depression scores in mental tests of participants with their gut microbiome composition. Notably, depression was associated with changes in the abundance of Lachnospiraceae Eubacterium xylanophilum group and Fusobacteriaceae Fusobacterium . Additionally, bacterial pathways involved in metabolising neuroactive compounds such as tryptophan, short-chain fatty acids, p-cresol, glutamate, and nitric oxide were associated with participant age, sex, and cognitive performance. Moreover, participants’ sex was associated with the neuroactive potential of specific bacteria, suggesting a role of the gut microbiome in sex-related mental health differences in the elderly. Altogether, this study provides the first evidence from a South American cohort linking the inferred neuroactive potential of the gut microbiome to cognitive and psychological function in older adults with cognitive complaints, offering novel insights into microbiota-based mechanisms that may contribute to mental health and ageing.
Chemical Proteomics Reveal the Inventory of Pyrroloquinoline Quinone Binding Proteins in Bacteria
Two-dimensional p-π conjugated amide-linked polymeric photocatalysts with enhanced carrier separation
Bioinformatics analysis and qRT-PCR validation of iron metabolism-related genes in pediatric asthma
Pediatric asthma (PA) is a chronic airway disease with a complex etiology, and iron metabolism disorder is believed to be involved in its pathogenesis. In this study, we integrated three peripheral blood transcriptome datasets from the GEO database (GSE27011, GSE40888, GSE40732), which included 283 samples (155 in the PA group and 128 in the control group), and conducted a comprehensive analysis after normalization and batch effect correction. Differential expression analysis identified 15 iron metabolism-related differentially expressed genes (IMRDEGs), including C19orf12, IREB2, XK, GDF15 . Functional enrichment analysis showed that these genes mainly participate in cellular energy metabolism, oxidative stress response, and regulation of iron homeostasis. A discrimination model based on machine learning algorithms isolated four key genes, with an area under the receiver operating characteristic curve of 0.69, indicating moderate diagnostic discrimination. qRT-PCR analysis of independent blood samples showed that C19orf12 expression was upregulated in patients with PA, while IREB2 expression was downregulated, consistent with bioinformatics analysis results. Immune infiltration analysis revealed significant differences in the proportions of memory CD4 + T cells and mast cells between high-risk and low-risk groups, suggesting that iron metabolism imbalance may contribute to asthma development via immune regulatory mechanisms. This study provides combined support from transcriptomic and experimental data for the potential role of IMRGs in PA, serving as a basis for further mechanistic research and clinical validation.
Photocatalytic, Regioselective Enone Deconjugation: An Enabling Platform for Terpene Modification
Host genotype and sex shape influenza evolution and defective viral genomes
Clinical factors associated with severe maternal outcomes in two South African hospitals: A case-control study
Background A persistently high maternal mortality ratio (MMR) from direct pregnancy causes of maternal deaths in a district of the Gauteng Province prompted a detailed audit to identify clinical factors associated with severe maternal outcomes (SMOs). Methods A cross-sectional matched case control study design was used to identify clinical factors associated with severe maternal outcomes in two regional hospitals in an urban district in Gauteng. 175 sequential SMO cases (near misses and maternal deaths) were matched to two different controls each. The first control was of women with complications while the second control was of women without complications. Data on individual and clinical obstetric characteristics of cases and controls was extracted from clinical case files. A Firth penalised conditional logistic regression was used to identify the clinical factors associated with severe maternal outcomes. Results The overall SMO incidence ratio and MMR were 34.7 per 1000 live births and 130.8 per 100 000 live births respectively. Haemorrhage (48.8%) and hypertension (46.9%) were the most common underlying causes of SMOs. The SMO incidence ratio was 39.0 and 30.2 per 1000 live births for Hospital 1 and 2 respectively. Not receiving antenatal care was the most significant risk for SMOs (p < 0.001). In women with complications, not initiating ANC attendance (AOR = 11.0; CI = 2.6–46.0) or having less than 4 ANC visits (AOR = 2.2; CI = 1.2–4.2) had the highest risk for SMOs (p < 0.001). In women without complications, anaemia (AORs = 3.0; CI = 1.4–6.6; p < 0.01), and hypertension (AORs = 71; CI = 4.2−1,196.2), significantly increased the odds of SMOs. Conclusions The severe maternal incidence was high in both hospitals. Obstetric haemorrhage and hypertension were significantly associated with most SMOs. Not attending ANC and having few ANC visits were important factors that showed significant association with poor maternal outcomes.