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Pegivirus-Associated Encephalomyelitis in Immunosuppressed Patients

Canada’s election: what Mark Carney’s win means for science

BCG Revaccination for the Prevention of <i>Mycobacterium tuberculosis</i> Infection

Complete sequencing of ape genomes

Abstract The most dynamic and repetitive regions of great ape genomes have traditionally been excluded from comparative studies 1–3 . Consequently, our understanding of the evolution of our species is incomplete. Here we present haplotype-resolved reference genomes and comparative analyses of six ape species: chimpanzee, bonobo, gorilla, Bornean orangutan, Sumatran orangutan and siamang. We achieve chromosome-level contiguity with substantial sequence accuracy (&lt;1 error in 2.7 megabases) and completely sequence 215 gapless chromosomes telomere-to-telomere. We resolve challenging regions, such as the major histocompatibility complex and immunoglobulin loci, to provide in-depth evolutionary insights. Comparative analyses enabled investigations of the evolution and diversity of regions previously uncharacterized or incompletely studied without bias from mapping to the human reference genome. Such regions include newly minted gene families in lineage-specific segmental duplications, centromeric DNA, acrocentric chromosomes and subterminal heterochromatin. This resource serves as a comprehensive baseline for future evolutionary studies of humans and our closest living ape relatives.

Classification of very low birth weight infants as small for gestational age: International vs. national standards

Background It is not precisely known whether the use of national (Carrascosa 2008) and international growth standards (INTERGROWTH-21) shows good concordance in classifying very low birth weight infants as small-for-gestational-age or whether with the same degree of morbidity and mortality. The aims of this study were a) to evaluate the concordance between small-for-gestational-age neonates weighing &lt;1500 g classified using the national and international standards, and b) to compare the morbidity and mortality of small-for-gestational-age neonates classified by both standards. Methods A retrospective cohort study was conducted with very low birth weight infants. The concordance between the INTERGROWTH-21 and Carrascosa 2008 standards was analyzed, along with differences in gestational age, weight, medical requirements, morbidity, and mortality, among small-for-gestational-age neonates classified by both standards. Small-for-gestational-age was defined as a birth weight z score ≤ −1.28. Results A total of 250 neonates weighing &lt;1500 g, who were born between 26 and 36 weeks of gestation, were included. There was a high level of concordance in the classification of small-for-gestational-age between the two standards (Cohen’s kappa = 0.80, p &lt; 0.001). A lower incidence was observed when the INTERGROWTH-21 standard was used (31.6%) compared to the Carrascosa 2008 standard (40.8%), p = 0.03. No significant differences were found in mortality or morbidity among neonates classified as small-for-gestational-age by both standards. Conclusion The Carrascosa 2008 and INTERGROWTH-21 standards classify small-for-gestational-age infants with comparable morbidity and mortality. We recommend the use of the INTERGROWTH-21 standard for its inclusion of multiple pregnancies, diverse ethnicities, and international comparability.

Vutrisiran in Patients with Transthyretin Amyloidosis with Cardiomyopathy

Effects of different irrigation amounts on soil structure in newly cultivated land on the Loess Plateau

It is imperative to promote water-saving irrigation technology and develop newly cultivated land in the Loess Plateau. This study focused on the interaction between roots and soil to examine the effects of different amounts of irrigation on soil structure of newly cultivated land. Herein, five irrigation levels were set, i.e., sufficient irrigation (W100), mild deficit irrigation (W80), moderate deficit irrigation (W60), severe deficit irrigation (W40), and rain-fed (RF). Physical properties and structural stability indexes of the rhizosphere soil were measured, and their relationship with plant root morphology were analyzed. The results showed that the soil structure under the high irrigation amount group (W80 and W100) was relatively stable. The average particle density of soil in each plot decreased significantly after the experiment, while the soil total porosity remained unchanged in W80 and W100 treatments. The proportion of large aggregates, the mean weight diameter, and the geometric mean diameter of soil significantly reduced in the low irrigation amount group (RF, W40, and W60). In contrast, the W100 and W80 treatments inhibited the decline in soil aggregate stability. Change in the generalized soil structure index (GSSI) and soil three-phase structure distance (STPSD) of W100 and W80 treatments were not significant, before and after the experiment. These results suggested that the soil in newly cultivated land treated with sufficient and mild deficit irrigation was closer to the ideal state for crops growing. Path analysis identified the average soil moisture content had the greatest negative effect on STPSD primarily through the root length, root surface area, and root dry weight. In conclusion, irrigation amount occupies a dominant position among all factors influencing soil structure considered in the study. And the mild deficit irrigation is suitable for agricultural cultivation in the Loess Plateau area, from the soil structure protection and water-saving perspectives.

Characteristics of Friction Stir Welding of 3 mm thick ABS and PC thermoplastic polymers: An experimental approach

The utilization of thermoplastics is extensively prevalent in modern industrial sectors owing to their distinctive mechanical features. Friction stir welding is recognized as a distinctive joining technology that addresses the weaknesses of heat-induced fusion welding. This friction-stirred solid-state welding technology can be effectively employed to join various difficult-to-weld polymeric materials. This paper examines the weldability of friction stir butt welding utilizing a cylindrical tapered threaded tool on a 3 mm thick Acrylonitrile Butadiene Styrene (ABS) and Polycarbonate (PC) polymers. The impact of tool rotational speed (800 and 1200 rpm) and tool traverse speed (10 mm/min to 50 mm/min) on the joint strength of welded samples has been analyzed. The maximum joint efficiency achieved is 52.71% for ABS while using a rotational speed of 1200 RPM and a traverse speed of 10 mm/min. For PC, the maximum joint efficiency is 54% with a rotational speed of 800 RPM and a traverse speed of 40 mm/min. The joint efficiency of polymer is significantly improved as a result of the effective heat distribution and fusion during the welding. The tensile strength of ABS polymer decreases as the traverse speed increases from 10 mm/min to 50 mm/min at both rotational speeds of 800 and 1200 rpm. However, the tensile strength of PC polymer exhibits fluctuations as the traverse speed increases from 10 mm/min to 50 mm/min. This behavior may be attributed to the fluctuating heating and cooling conditions that occur during the welding process at varying rotation and traverse speeds. In contrast to the polymeric base material, the weld zone demonstrated a lower hardness value. The heated tool induces material softening, which results in a reduction in hardness. An examination of alterations in the microstructure of the weld zone was conducted using scanning electron microscopy and stereo microscopy. The observed microstructures were applied to determine the reasons for the decrease in strength. The micrographs illustrate the formation of a fragmentation, attributable to the residual stress generated during the rapid cooling of the liquid polymer. Moreover, a highly increased temperature or traverse speed may result in the formation of voids at the joint interface.

RETRACTED: Optimizing the impact of time domain segmentation techniques on upper limb EMG decoding using multimodal features

Neurological disorders, such as stroke, spinal cord injury, and amyotrophic lateral sclerosis, result in significant motor function impairments, affecting millions of individuals worldwide. To address the need for innovative and effective interventions, this study investigates the efficacy of electromyography (EMG) decoding in improving motor function outcomes. While existing literature has extensively explored classifier selection and feature set optimization, the choice of preprocessing technique, particularly time-domain windowing techniques, remains understudied posing a significant knowledge gap. This study presents upper limb movement classification by providing a comprehensive comparison of eight time-domain windowing techniques. For this purpose, the EMG data from volunteers is recorded involving fifteen distinct movements of fingers. The rectangular window technique among others emerged as the most effective, achieving a classification accuracy of 99.98% while employing 40 time-domain features and a L-SVM classifier, among other classifiers. This optimal combination has implications for the development of more accurate and reliable myoelectric control systems. The achieved high classification accuracy demonstrates the feasibility of using surface EMG signals for accurate upper limb movement classification. The study’s results have the potential to improve the accuracy and reliability of prosthetic limbs and wearable sensors and inform the development of personalized rehabilitation programs. The findings can contribute to the advancement of human-computer interaction and brain-computer interface technologies.

Comparison of single and double chest drains following pulmonary lobectomy

Background Chest tubes are commonly used to empty the chest cavity after pulmonary lobectomy. Although two drains have traditionally been used to guarantee proper air and fluid evacuation, they frequently cause patients more pain and lengthen their hospital stays. This study set out to compare the effectiveness of using a single chest drain versus using two chest drains after a pulmonary lobectomy. Methods This retrospective trial was performed on 50 patients aged ≥18 years, both sexes, scheduled for Video-Assisted Thoracic Surgery (VATS) lobectomy. Patients were divided into two equal groups: Group S: single chest tube was used and Group D: double chest tubes were used. Results The duration of drainage was 3.32 ± 0.69 days in group S and was 4.2 ± 1.29 days in group D (P &lt; 0.05). The amount of drainage was 593.64 ± 45.94 ml in group S and was 910.04 ± 71.42 ml in group D (P &lt; 0.05). Assessment of the pain using the visual analog scale on second day was insignificantly different between both groups and was significantly lower at the second postoperative week in group S than in group D (P = 0.005). Length of hospital stays and complications (pneumonia, re-drainage, and persistent air leak (&gt; 7 days)) were insignificantly different between both groups. Conclusions The effectiveness of inserting one chest tube following a pulmonary lobectomy is comparable to that of inserting two tubes. Furthermore, employing a single tube is more advantageous than two tubes, as it is associated with lower postoperative pain, duration and amount of drainage.

Gene delivery of AGAT and GAMT boosts creatine levels in creatine transporter deficiency patient fibroblasts

Creatine is a critical metabolite used to buffer cellular energy demands in highly energetic tissues such as the brain and muscle. Genetic defects in endogenous creatine synthesis or transport across cellular membranes lead to a common set of phenotypes referred to as Cerebral Creatine Deficiency Syndrome (CCDS). The most common form of CCDS is Creatine Transporter 1 (CT1) Deficiency (CTD). It accounts for ~ 70% of cases and results from loss-of-function mutations in the X-linked gene SLC6A8. Affected individuals suffer from intellectual disability, autistic-like behaviors, and epilepsy. There are currently no effective therapies for this disorder, but gene therapy has emerged as a potential approach. The two enzymes which comprise the endogenous creatine synthetic pathway (AGAT and GAMT) are selectively expressed by specific cell types throughout the body. However, after synthesized, creatine uptake relies on the protein product of SLC6A8, CT1, to transport creatine into target cell types. We hypothesized that gene delivery of GATM (encoding AGAT) and GAMT into end-user cell types would bypass the need for CT1, allowing for intracellular synthesis of creatine. We tested this strategy in two human cell types: HEK293T cells and primary fibroblasts. Co-delivery of GATM and GAMT increased internal creatine concentrations by 7.6-fold in HEK293T cells and 12.3-fold in healthy control fibroblasts. We then employed this approach to primary fibroblasts from patients with CTD. This resulted in an up to 11.6-fold increase in intracellular creatine concentrations, far exceeding the intracellular concentration of creatine in healthy control fibroblasts. Importantly, overexpression of AGAT and GAMT resulted in proper targeting of these enzymes to their natural cellular compartment and did not impair the growth of patient fibroblasts. These findings establish gene therapy with GATM and GAMT as a potential strategy for patients with CTD.

Help! – you need your hands: Contribution of arm movements on balance performance in healthy individuals: A systematic review with meta-analysis

Background Emerging evidence highlights that arm movements exert a substantial and functionally relevant contribution on postural control in healthy individuals. However, performance differences between free versus restricted arm movement for different balance categories with varying levels of task difficulty have not been systematically investigated yet. Objective The objective of this systematic review and meta-analysis was to characterise, aggregate, and quantify performance discrepancies between free and restricted arm movement conditions for diverging balance categories with varying levels of task difficulty in healthy individuals. Methods A systematic search of the literature according to the PRISMA guidelines was performed on the electronic databases PubMed, Web of Science, and SPORTDiscus from their inception date till 1st September 2024. To be applicable for analysis, studies had to report at least one measure of balance performance in healthy individuals. The included studies were coded according to the following criteria: age, sex, status, arm movement conditions, balance test, and test modality. Methodological study quality was assessed using the Appraisal tool for Cross-Sectional Studies. Weighted standardized mean differences (SMD) were calculated and classified according to their magnitude. Results The literature search identified a total of N = 941 records, 25 of which met the inclusion criteria and were analysed in this review. A total of 725 participants (n = 331 females) participated in the studies. The free use of arm movement resulted in moderate (static: SMD = 0.51, dynamic: SMD = 0.66, proactive: SMD = 0.52, reactive: SMD = 0.50) improvements of balance performance. In addition, the performance enhancements were more pronounced for balance tasks with a high (static: SMD = 0.89, dynamic: SMD = 1.04) compared to a low (static: SMD = 0.20, dynamic: SMD = 0.76) difficulty level. Due to a lack of studies, no analysis for measures of proactive and reactive balance was performed. Conclusions The findings revealed that the free use of arm movement positively affects several measures of balance performance, and this is effect is more pronounced for balance tasks with a high difficulty level.

For these bats, eavesdropping is a valuable learnt skill

Self-supervised learning framework for efficient classification of endoscopic images using pretext tasks

Identifying anatomical landmarks in endoscopic video frames is essential for the early diagnosis of gastrointestinal diseases. However, this task remains challenging due to variability in visual characteristics across different regions and the limited availability of annotated data. In this study, we propose a novel self-supervised learning (SSL) framework that integrates three complementary pretext task, colorization, jigsaw puzzle solving, and patch prediction, to enhance feature learning from unlabeled endoscopic images. By leveraging these tasks, our model extracts rich, meaningful representations, improving the downstream classification of Z-line, esophageal, and antrum/pylorus regions. To further enhance feature extraction and model interpretability, we incorporate attention mechanisms, transformer-based architectures, and Grad-CAM visualization. The integration of attention layers and transformers strengthens the model’s ability to learn discriminative and generalizable features, while Grad-CAM improves explainability by highlighting critical decision-making regions. These enhancements make our approach more suitable for clinical deployment, ensuring both high accuracy and interpretability. We evaluate our proposed framework on a comprehensive dataset, demonstrating substantial improvements in classification accuracy, precision, recall, and F1-score compared to conventional models trained without SSL. Specifically, our combined model achieves a classification accuracy of 98%, with high precision and recall across all classes, as reflected in ROC curves and confusion matrices. These results underscore the effectiveness of pretext-task-based SSL, attention mechanism, and transformers for anatomical landmark identification in endoscopic video frames. Our work introduces a scalable and interpretable methodology for improving endoscopic image classification, reducing reliance on large annotated datasets while enhancing model performance in real-world clinical applications. Future research will explore validation on diverse datasets, real-time diagnostic integration, and scalability to further advance medical image analysis using SSL.

Tattoo-making tools used by ancient Maya revealed

Stress dynamically modulates neuronal autophagy to gate depression onset

The spatiotemporal evolution of flight-coupled wind field for a four-rotor plant protection unmanned aerial vehicle

The four-rotor plant protection Unmanned Aerial Vehicle (UAV) is an important piece of equipment for the efficient plant protection field. However, the flight-coupled wind field is unclear, which has become the bottleneck factor limiting the improvement of the spray quality. When the multi-rotor plant protection UAV flew and sprayed, the liquid droplets were accelerated, the stems and branches were shaken, and the leaves were turned over in the disturbance area of the spiral backward flight-coupled wind field. The flight-coupled wind field, liquid droplets and crop canopy were closely related. Only when the flight-coupled wind field was analyzed could the interaction mechanism among the flight-coupled wind field, liquid droplets, and crop canopy be effectively studied, then the flight and spray scheme could be reasonably formulated. By combining the Re-Normalization Group (RNG) k-ε turbulence model, compressible Reynolds Averaged Navier-Stokes (RANS) equation, the dynamic mesh based on the spring smoothing and layering method, pressure-velocity coupling algorithm, a computational fluid dynamics (CFD) model of the flight-coupled wind field for the four-rotor plant protection UAV was established, the dynamic evolution law of the flight-coupled wind field in the spatial and temporal dimensions was also discussed in this paper. Numerical simulations were carried out for flight-coupled wind fields in two working conditions, analysis showed that the maximum relative error between the simulated and measured values of Zb-direction (Z direction in the absolute coordinate system) velocity was less than 12.7% when the flight-coupled wind field was stable. When switching from hover to flight state, the downwash wind field experienced a lateral interruption and developed into the stable flight-coupled wind field after flying for 0.696 s, and the velocity distribution diagram of the cross section evolved from four rings to four horseshoe vortices. When the flight-coupled wind field evolved to stabilize, the dense atmosphere reduced the absolute values of the four Zb-direction velocity peaks at observation line 1 from left to right along the flight direction by 4.5%, 4.2%, 9.0%, and 26.1% respectively. The angles between the horizontal direction and the four curves formed by Zb-direction velocity peaks were also changed from 90° to 72°, 69°, 61°, and 56° respectively at the flight speed of 3 m/s. Therefore, the installation of the nozzle and the formulation of the spray strategy are crucial to improve the spray deposition effect.

Holographic tomography of the diatom Skeletonema pseudocostatum used as a bioindicator of heavy metal-polluted waters

Heavy metal contamination in aquatic environments poses a significant threat to microbial communities, yet the subcellular responses of phytoplankton to metal stress remain poorly understood. In particular, the effects of heavy metal exposure on the structural and physiological properties of diatoms require further investigation. Here, we analyze the impact of cadmium (Cd) and copper (Cu) exposure on the subcellular structures of the diatom Skeletonema pseudocostatum using holographic tomography. This imaging technique enables detailed visualization and quantitative analysis of diatom subcomponents, including frustules, protoplasm, vacuoles, and chloroplasts, under varying metal concentrations. The study aims to understand the changes in the mean refractive index (RI) and concentration (e.g., the ratio among cell dry mass and its biovolume) as indicators of cellular response to metal stress and to infer if such diatom can be used as sentinel species of heavy metal pollution. Findings indicate that diatoms exhibit significant variations in RI and internal cell density when exposed to different metal concentrations. Lower RI values observed at higher metal concentrations, can be considered as a sign of stress due to cytoplasm extrusion and/or vacuolization. The results highlight the potential of using S. pseudocostatum as a bioindicator for monitoring water metal pollution. Moreover, the results show that holographic tomography as useful tool for non-invasive, high-resolution cellular imaging of phytoplankton in environmental studies.

COVID vaccine works faster with both doses in the same arm

Sex differences in alcohol inhibits bone formation and promotes bone resorption in young male and female rats by altering intestinal flora, metabolites, and bone microenvironment

Background Long-term alcohol intake has toxic effects on osteoblasts and osteoclasts, resulting in decreased bone density, which directly disrupts the composition of the gut microbiota and affects bone metabolism and immune activity. The effects of alcohol on the bones may be closely related to sex. This study investigated the effects of long-term alcohol consumption on bone status in different sexes by examining the gut microbiota, bone metabolism, and immune activity. Methods Young male and female rats were administered a Bio-Serv liquid diet containing 5% alcohol. The effects of alcohol metabolism capacity, bone morphology, bone formation, bone resorption, bone marrow immune activity, gut microbiota, and metabolite differences were analyzed in male and female rats using hematoxylin and eosin staining, micro-computed tomography, enzyme-linked immunosorbent assay, western blotting, 16S rRNA sequencing, and untargeted metabolomics. Results Chronic alcohol consumption resulted in excessive osteoclast activation and decreased bone mineral density. Furthermore, alcohol reduced bone metabolism and formation while increasing bone resorption. Bone loss was significantly more severe in female rats than in male rats, indicating that the effects of alcohol on rat bones are related to sex. Chronic alcohol consumption also led to polarization of bone marrow immunoreactivity toward the M1 phenotype. In addition, chronic alcohol consumption affected the composition of gut microbiota, reduced the richness and diversity of intestinal microbiota, and decreased the ratio of Firmicutes/Bacteroidetes. Long-term alcohol consumption also affected fecal metabolites, and 754 differentially expressed metabolites were identified. Conclusions Chronic alcohol consumption increased bone resorption, inhibited bone formation, and affected bone marrow immunoreactivity in young male and female rats. Alcohol can also affect gut microbiota composition and fecal metabolism. Female rats were more susceptible to alcohol, possibly because young female rats have a lower alcohol metabolism, immunomodulatory capacity, and gut microbiota diversity than young male rats.