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Cryovial versus straw for sheep semen cryopreservation: a comparative study of surface area-to-volume ratio on post-thaw viability and in vitro embryo production
No full textAbstract Semen cryopreservation results in decreased viability and fertilizing ability due to temperature variation-mediated cryodamage limiting its practical application. Though many factors play a role in the success of semen cryopreservation, ice crystal formation plays an important role in post-thaw viability because of the position and surface area to semen volume ratio of the container. The present study was to compare the post-thaw cryo-survivability of sheep semen cryopreserved in cryovials with a smaller surface area to semen volume ratio in the vertical position versus straws with a larger ratio in both horizontal and vertical positions. Significantly (p < 0.05) higher post-thaw functional parameters and subsequent embryo production were observed in the semen cryopreserved in cryovials with LN2 vapour than cryopreserved in straws with a bio-freezer and LN2 vapour. The study concluded that higher post-thaw viability of the sperm cryopreserved in cryovials in the vertical position might be due to gravity-supported settling of the sperm at the bottom, creating a small air gap, and resulting in less ice crystal formation and subsequent embryo production in vitro. Whereas the straws in the horizontal position created a large air gap and faster ice crystal formation, and uneven distribution of temperature along the length of the straw in the vertical position leads to significant (p < 0.05) sperm damage for subsequent embryo production
Evidence of a genomic basis for growth rate variation in a natural kelp population
No full textAbstract Understanding the genetic architecture of functional traits can provide key insights into the ecological dynamics and adaptive potential of species. We investigated whether genetic data can predict growth rate variation in a natural population of the widespread kelp, Ecklonia radiata. We tagged kelps and tracked their growth in situ over spring when growth is maximal. Individual kelps were then genotyped using reduced representation sequencing (ddRAD) and we employed multiple approaches to assess whether genetic variation corresponded with growth rate variation. Despite a limited sample size, we found evidence that growth rate can be strongly predicted from genetic variation, with approximately half of the variation in growth rate predicted by only 18 loci (R2 = 0.499). Leveraging published transcriptomic data, we confirm that most of these loci are expressed or are linked to expressed putative genes. However, many of these genes are of unknown function and do not match well-known gene families. These findings have important implications for understanding natural kelp forest dynamics and for applied approaches such as selective breeding and aquaculture. While our study offers an important first assessment of the possible genomic architecture underlying growth rate in E. radiata, future work is needed to confirm this apparent link between genetic and functional variation
AI based sagittal spinal posture assessment for adolescent screening in low resource school settings
No full textAbstract Adolescent spinal postural deviations are rising across Southeast Asia, driven by prolonged screen exposure and limited access to clinical screening in low-resource environments. To address this gap, we developed PostureGuard, a low-cost AI system that provides real-time posture assessment and school-based screening support. The system incorporates a Southeast Asia–calibrated pose estimation model, benchmarked against radiographic references and validated using wearable sensor measurements. In a field deployment involving 200 students across 15 Indonesian schools, PostureGuard achieved a mean absolute error below 2.3° for forward head angle estimation. We further identified a dose–response association in which each additional hour of daily screen time was associated with an estimated 2.1° increase in forward head angle. A preliminary six-month school implementation suggested improvements in posture-related indicators; however, these observations were not derived from a controlled clinical trial. PostureGuard has since been piloted within Indonesia’s 2024 Digital Wellness Mandate initiative. This work presents a regionally calibrated AI-based posture screening framework with clinical benchmarking and demonstrated scalability for adolescent spinal health monitoring in resource-limited settings
Gut microbiota and resistome profiles of Swiss expatriates in Africa revealed by Nanopore metagenomics
No full textAbstract The gut microbiota and resistome may change upon exposure to environments with high prevalence of multidrug-resistant pathogens, potentially impacting health and contributing to the spread of antimicrobial resistance genes (ARGs). In this context, expatriates may acquire endemic microbial communities and ARGs while living abroad. In this work, we investigated the microbiota and resistome of Swiss expatriates living in African countries using Nanopore shotgun metagenomics (SMS). Stool samples from expatriates residing in African and European countries (n = 33 and n = 39, respectively) were sequenced using Nanopore V14 chemistry. Taxonomic and resistome profiling was performed with Kraken2 and ResFinder, respectively. Diversity metrics (e.g., Shannon, Simpson) assessed microbial composition. ARG and bacteria associations were determined using GTDB-Tk on metagenome-assembled genomes (MAGs). Plasmid-borne ARGs were characterized with PlasmidFinder. Our results indicated that microbiota composition did not differ between expatriates in African and European countries. However, resistome analysis revealed a higher prevalence of tetracycline (tet) and folate pathway antagonist (dfr, sul) ARGs in those residing in Africa, suggesting adaptation to the local microbial environment or antibiotic policy. Unique plasmid families were also identified in Gram-negative (IncF) and -positive (repUS43) bacteria across African and European cohorts, indicating the potential for ARG dissemination via mobile genetic elements. Overall, Nanopore-based SMS may provide an alternative approach to monitor microbiota and resistome dynamics, and thus assisting early epidemiological surveys
24-hour ambulatory blood pressure and associated factors in women with polycystic ovary syndrome compared with ovulatory controls
No full textAbstract To compare 24-hour ambulatory blood pressure (ABP) between women with polycystic ovary syndrome (PCOS) and ovulatory controls, and to explore potential anthropometric, hormonal, metabolic, and inflammatory correlates of ABP in women with PCOS. In this cross-sectional study, 50 women with PCOS (diagnosed by Rotterdam criteria) and 50 ovulatory controls underwent office and 24-hour ABP monitoring. Clinical, anthropometric, hormonal, metabolic, and inflammatory parameters were assessed. Between-group comparisons were adjusted for body mass index (BMI). LASSO regression was used to identify variables independently associated with ABP in the PCOS group. Women with PCOS showed significantly higher 24-hour and daytime mean arterial pressure and heart rate compared to controls, even after adjustment for BMI (p 0.05). PCOS participants exhibited a more adverse cardiometabolic profile, including higher BMI, waist circumference, insulin, HbA1c, triglycerides, creatinine, and TNF-alfa, along with lower estradiol and progesterone levels. In LASSO models, BMI emerged as the only consistent independent predictor of ABP across all periods. Additional predictors, such as HbA1c (nighttime mean BP), creatinine (daytime diastolic BP), and waist circumference (daytime systolic BP), were retained in specific models, while most hormonal, metabolic, and inflammatory markers were not associated with ABP in the PCOS group. In summary, women with PCOS exhibit higher 24-hour and daytime ABP compared to ovulatory controls, independently of BMI. Adiposity, as assessed by BMI, appears to be a key factor associated with ABP in this population. These findings highlight the importance of 24-hour ABP monitoring and weight management in the cardiovascular risk assessment and care of women with PCOS
Quantum kernel methods for marketing analytics with convergence theory and separation bounds
No full textAbstract This work studies the feasibility of applying quantum kernel methods to a real consumer classification task in the NISQ regime. We present a hybrid pipeline that combines a quantum-kernel Support Vector Machine (Q-SVM) with a quantum feature extraction module (QFE), and benchmark it against classical and quantum baselines in simulation (hardware validation remains future work). Hyperparameters were selected via nested cross-validation on the training partition and then fixed for test evaluation; under these settings, the proposed Q-SVM attains 0.7790 accuracy, 0.7647 precision, 0.8609 recall, 0.8100 F1, and 0.83 ROC AUC, exhibiting higher sensitivity while maintaining competitive precision relative to classical SVM. All headline metrics are obtained via high-fidelity simulation. We interpret these results as an initial indicator and a concrete starting point for NISQ-era workflows and hardware integration, rather than a definitive benchmark. Methodologically, our design aligns with recent work that formalizes quantum–classical separations and verifies resources via XEB-style (Cross-Entropy Benchmarking) approaches, motivating shallow yet expressive quantum embeddings to achieve robust separability despite hardware noise constraints
Broad spectrum antimicrobial nanoparticles with low toxicity to prevent biofilm formation on urologic devices
No full textAbstract Antimicrobial coatings for medical implants are critical in preventing device failures and infections. Antibiotics are often used as prophylactic or coatings but fail to prevent biofilm formation and drive antibiotic resistance. Herein, the antibacterial and antibiofilm activities of different polyhydroxy fullerene-based metal nanoparticle coatings on polyurethane discs were quantified after exposure to Escherichia coli. Gold-silver nanoparticles (GSNP) exhibited superior antibacterial activity compared to other silver-containing nanoparticles. GSNPs were evaluated against Escherichia coli, Enterococcus faecalis, Enterobacter hormaechei, Klebsiella oxytoca, Staphylococcus aureus and Staphylococcus epidermidis isolated from ureteral stents and inflatable penile prostheses and achieved 100% reduction of all tested urologic pathogens at physiological relevant bacterial loads (p < 0.0001). GSNPs inactivate bacteria by reactive oxygen species production with the estimated minimum inhibitory concentrations slightly higher for Gram-positive than Gram-negative bacteria with highest observed for S. epidermidis at 2.23 µg/mL. Safety studies with fibroblasts demonstrate that GSNPs at estimated minimum inhibitory concentrations have minimal effect (< 20%) on cell viability. Further, the GSNPs were able to reduce bacteria by six logs more than commercial nanoparticles. GSNPs represent a promising strategy for preventing biofilm formation on medical devices and implants due to their broad antibacterial activity and low toxicity
Mechano-stress endorsing heterogeneous lung cancer cells migration into confined channels and investigating tumor spheroids growth of confined space migrating cells
No full textAbstract Cancer cells in the tumor microenvironment and in the metastatic cascade leverage their different intrinsic and extrinsic properties to overcome the confined barriers of the metastatic cascade during metastasis. Although various studies have focused on cell migration under confinement, how the heterogeneity in the stiffness levels of single lung cancer cells affects their migration into confined spaces and the growth of tumor spheroids of confined space migrating cells remains unknown. This study explores how cancer cells with varying stiffness levels steer confined spaces and form post-migration tumor spheroids. Using a single-cell migration platform and a confined trans-well migration setup, the research uncovers that lung cancer cells with lower stiffness and reduced VIM expression exhibit selective migration into confined spaces. These cells, forming irregularly shaped spheroids post-migration, display nuclear shape deformation and downregulated VIM and LMNA genes linked to cell and nuclear stiffness. The findings highlight the heterogeneity of cancer cell migration in confined environments and the subsequent growth of tumor spheroids
Dysfunctional connectivity within hippocampal and entorhinal networks underlies early-life iron deficiency induced social recognition deficits, a preliminary study
No full textAbstract Early-life iron deficiency (EID) has an adverse effect on cognition. Previous MRI studies revealed that EID could produce brain structural changes, while the significance remains elusive. To elucidate correlative functional changes is thus important. A low-iron diet feeding protocol was used to produce EID in rats, and a three-chamber test was used to evaluate social recognitions. T2-weighted and functional MRI (fMRI) were employed to conduct voxel-based morphometry (VBM) and voxel-wise functional connectivity (FC) analyses. Seed-based FC analyses were conducted, and based on the results, the hippocampus and entorhinal cortex (EC) were further respectively subdivided into 8 and 5 subregions, in order to perform deep seed-based FC analyses. EID rats were significantly impaired in social recognition. VBM analyses showed enlarged hippocampus and EC, and the FC between them was significantly decreased. Our deep seed-based analyses of FC further identified the impaired networks (p < 0.001, q < 0.05) between these two brain regions and between each of them and a number of other brain networks individually. All these results, although preliminarily, for the first time revealed the dysfunctional connectivity in three networks within the hippocampus and EC of the brain of EID rats, and may have a translational significance in early-diagnosis of EID
Hybrid quantum–chaotic key expansion enhances QKD rates using the Lorenz system
No full textAbstract Quantum key distribution (QKD) provides a foundation for information-theoretic security based on quantum mechanics, yet its practical deployment is often constrained by intrinsically low secure key generation rates, particularly in high-bandwidth or low-latency settings. This work introduces a hybrid cryptographic technique that integrates conventional QKD with deterministic chaos, modeled using the Lorenz attractor, to provide a software-based enhancement of the effective key expansion rate. From a short 20-bit QKD seed, the system generates long bitstreams within milliseconds; although these streams exhibit high empirical randomness, their fundamental entropy remains bounded by the seed, consistent with standard cryptographic principles. The method employs the exponential divergence of chaotic trajectories, such that even minute uncertainties in an adversary’s estimate of the initial state lead to rapid desynchronization and, as established in Appendix A, an exponential decay of Eve’s mutual information with respect to the expanded key. Simulation results confirm this theoretical behavior and demonstrate an effective rate amplification exceeding two orders of magnitude over the baseline QKD seed rate. The proposed chaotic expansion operates entirely in software and requires no modifications to existing QKD hardware, offering a practical pathway to enhance throughput for applications ranging from secure video communication to low-latency IoT and edge-computing environments
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