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Unraveling the distinctive gut microbiome of khulans (Equus hemionus hemionus) in comparison to their drinking water and closely related equids

Abstract The microbial composition of host-associated microbiomes is influenced by co-evolutionary interactions, host genetics, domestication, and the environment. This study investigates the contribution of environmental microbiota from freshwater bodies to the gastrointestinal microbiomes of wild khulans (Equus hemionus hemionus, n = 21) and compares them with those of captive khulans (n = 12) and other equids—Przewalski’s horse (n = 82) and domestic horse (n = 26). Using PacBio technology and the LotuS pipeline for 16S rRNA gene sequencing, we analyze microbial diversity and conduct differential abundance, alpha, and beta diversity analyses. Results indicate limited microbial sharing between wild khulans and their waterhole environments, suggesting minimal environmental influence on their gut microbiomes and low levels of water contamination by khulans. Wild khulans exhibit greater microbial diversity and richness compared to captive ones, likely due to adaptations to the harsh nutritional conditions of the Gobi desert. Conversely, captive khulans show reduced microbial diversity, potentially affected by dietary changes during captivity. These findings highlight the significant impact of environment and lifestyle on the gut microbiomes of equids.

Dual-channel near-field holographic MIMO communications based on programmable digital coding metasurface and electromagnetic theory

Proper 5’-3’ cotranslational mRNA decay in yeast requires import of Xrn1 to the nucleus

The budding yeast Xrn1 protein shuttles between the nucleus, where it stimulates transcription, and the cytoplasm, where it executes the major cytoplasmic mRNA decay. In the cytoplasm, apart from catalyzing 5’→3’ decay onto non translated mRNAs, Xrn1 can follow the last translating ribosome to degrade the decapped mRNA template, a process known as “cotranslational mRNA decay”. We have previously observed that the import of Xrn1 to the nucleus is required for efficient cytoplasmic mRNA decay. Here by using an Xrn1 mutant that cannot enter the nucleus, but is otherwise functional in ribonuclease activity, we show that nuclear import is necessary for proper global cotranslational decay of mRNAs along coding regions and also affects degradation in the of 5’ region of a large group of mRNAs, which comprise about 20% of the transcriptome. Furthermore, a principal component analysis of the genomic datasets of this mutant and other Xrn1 mutants also shows that lack of a cytoplasmic 5’→3’ exoribonuclease is the primary cause of the physiological defects seen in a xrn1Δ mutant, but also suggests that Xrn1 import into the nucleus is necessary for its full in vivo functions.

A comparative machine learning study of schizophrenia biomarkers derived from functional connectivity

Abstract Functional connectivity holds promise as a biomarker of schizophrenia. Yet, the high dimensionality of predictive models trained on functional connectomes, combined with small sample sizes in clinical research, increases the risk of overfitting. Recently, low-dimensional representations of the connectome such as macroscale cortical gradients and gradient dispersion have been proposed, with studies noting consistent gradient and dispersion differences in psychiatric conditions. However, it is unknown which of these derived measures has the highest predictive capacity and how they compare to raw functional connectivity specifically in the case of schizophrenia. Our study evaluates which connectome features derived from resting state functional MRI — functional connectivity, gradients, or gradient dispersion — best identify schizophrenia. To this end, we leveraged data of 936 individuals from three large open-access datasets: COBRE, LA5c, and SRPBS-1600. We developed a pipeline which allows us to aggregate over a million different features and assess their predictive potential in a single, computationally efficient experiment. We selected top 1% of features with the largest permutation feature importance and trained 13 classifiers on them using 10-fold cross-validation. Our findings indicate that functional connectivity outperforms its low-dimensional derivatives such as cortical gradients and gradient dispersion in identifying schizophrenia (Mann–Whitney test conducted on test accuracy: connectivity vs. 1st gradient: U = 142, p < 0.003; connectivity vs. neighborhood dispersion: U = 141, p = 0.004). Additionally, we demonstrated that the edges which contribute the most to classification performance are the ones connecting primary sensory regions. Functional connectivity within the primary sensory regions showed the highest discrimination capabilities between subjects with schizophrenia and neurotypical controls. These findings along with the feature selection pipeline proposed here will facilitate future inquiries into the prediction of schizophrenia subtypes and transdiagnostic phenomena.

Author Correction: Condensin-mediated restriction of retrotransposable elements facilitates brain development in Drosophila melanogaster

Construction of the national fitness public service satisfaction model in China based on American Customer Satisfaction Index

Objective The national fitness initiative in China is a strategic priority, public satisfaction is a key metric for evaluating the effectiveness of public services. The American Customer Satisfaction Index (ACSI) model has proven a robust tool for evaluating satisfaction with public services. The objective of study was to construct a satisfaction model for national fitness public services in China based on the ACSI framework and to explore the complex relationships among its components. Methods Evaluation dimensions and an item pool were carefully developed by referencing the ACSI model and relevant academic literature. After a panel of experts assessed the initial items pool, the study formed the questionnaire to distribute the residents in Guangzhou, a total of 1,133 valid responses were collected. Data analysis was conducted using SPSS 22.0 and AMOS 16.0 software to evaluate the reliability and validity of the measurement model, the goodness-of-fit of the structural model, and analyze the statistical significance of each path coefficient. Results Public expectation does not directly influence satisfaction (path coefficient 0.039, p = 0.103), it exerts a significant and direct influence on perceived quality (path coefficient 0.445, p = 0.003), which in turn demonstrably shapes public satisfaction (path coefficient 0.403, p = 0.005). Perceived quality also directly influences perceived value (path coefficient 0.735, p = 0.006), which in turn significantly impacts public satisfaction (path coefficient 0.554, p = 0.003). Public satisfaction directly and significantly influences both public complaints (path coefficient 0.395, p = 0.003) and public trust (path coefficient 0.699, p = 0.003). Conclusion Perceived quality is the most critical factor influencing public satisfaction, which subsequently affects public complaints and trust. Fitness service providers should consistently improve service quality, aligning actual service delivery with public expectations, and enhancing the perceived value for the public. These efforts will bolster the public’s satisfaction level.

Association between phase angle and all-cause mortality in adults aged 18–49 years: NHANES 1999–2004

The molecular basis of Human FN3K mediated phosphorylation of glycated substrates

Abstract Glycation, a non-enzymatic post-translational modification occurring on proteins, can be actively reversed via site-specific phosphorylation of the fructose-lysine moiety by FN3K kinase, to impact the cellular function of the target protein. A regulatory axis between FN3K and glycated protein targets has been associated with conditions like diabetes and cancer. However, the molecular basis of this relationship has not been explored so far. Here, we determined a series of crystal structures of HsFN3K in the apo-state, and in complex with different nucleotide analogs together with a sugar substrate mimic to reveal the features important for its kinase activity and substrate recognition. Additionally, the dynamics in sugar substrate binding during the kinase catalytic cycle provide important mechanistic insights into HsFN3K function. Our structural work provides the molecular basis for rational small molecule design targeting FN3K.

The impact of social networks on rural residents’ engagement in living environment upgrade: An integrated analysis drawing on social network theory and the theory of planned behavior

The issue of rural living environment is a critical concern for China and the global community, intricately intertwined with regional economic development. The proactive involvement of rural residents, who are both beneficiaries and influencers of the environment, constitutes a cornerstone in improving environmental standards. Therefore, the factors that shape rural residents’ participation in living environment upgrade must be explored. Drawing upon the theory of planned behavior and social capital theory, this study employs a structural equation model (SEM) to comprehensively examine the determinants of rural residents’ engagement in living environment upgrade, utilizing data from 334 households in Hebei Province, China. The findings can be summarized as follows: (1) Social networks, subjective norms, perceived behavioral control, and attitudes towards behavior significantly and positively impact rural residents’ engagement in upgrading the living environment, (2) Attitudes towards behavior act as mediators between perceived behavioral control and rural residents’ engagement in living environment upgrade, as well as between subjective norms and rural residents’ engagement in living environmental upgrade. (3) Social networks could indirectly influence rural residents’ engagement in living environment upgrade through the independent mediating effect of subjective norms and attitudes towards behavior, as well as through the chain mediating effect of the two. In conclusion, several managerial recommendations are proposed to stimulate rural residents’ active participation in living environment upgrade.

Identification of promising SARS-CoV-2 main protease inhibitor through molecular docking, dynamics simulation, and ADMET analysis

Abstract The COVID-19 pandemic caused by SARS-CoV-2 continues to pose a major challenge to global health. Targeting the main protease of the virus (Mpro), which is essential for viral replication and transcription, offers a promising approach for therapeutic intervention. In this study, advanced computational techniques such as molecular docking and molecular dynamics simulations were used to screen a series of antiviral compounds for their potential inhibitory effect on the SARS-CoV-2 Mpro. A comprehensive analysis of compounds from the ChemDiv and PubChem databases was performed. The physicochemical properties, pharmacokinetics, and ADMET (Absorption, Distribution, Metabolism, Excretion, and Toxicity) profiles were evaluated to determine drug similarity and safety. Compound 4896 − 4038 proved to be the most promising candidate. It exhibited a favorable balance between molecular weight (491.06) and lipophilicity (logP 3.957), high intestinal absorption (92.119%), and broad tissue distribution (VDss of 0.529), indicating good oral bioavailability and therapeutic potential. Molecular docking studies showed that 4896 − 4038 has a strong binding affinity to the active site of Mpro and forms key interactions, such as hydrogen bonds, carbon-hydrogen bonds, pi-sulfur, and multiple van der Waals and pi-pi stacked bonds. The binding energy was comparable to that of the reference drug X77, indicating potential efficacy. Molecular dynamics simulations over 300 ns confirmed the stability of the Mpro/4896 − 4038 complex of protein-ligand. Free energy landscape mapping and MM/PBSA calculations further substantiated the favorable binding and stability of the complex. Importantly, 4896 − 4038 exhibited a comparatively favorable safety profile. In summary, compound 4896 − 4038 shows significant potential as a potent SARS-CoV-2 Mpro inhibitor, combining potent inhibitory activity with favorable pharmacokinetic and safety profiles. These results support the further development of 4896 − 4038 as a promising therapeutic agent in the fight against COVID-19 that warrants experimental validation and clinical investigation.

Promoting in-situ stability of hydroxide exchange membranes by thermally conductive network for durable water electrolysis

What emotions does music express? Structure of affect terms in music using iterative crowdsourcing paradigm

Music is assumed to express a wide range of emotions. The vocabulary and structure of affects are typically explored without the context of music in which music is experienced, leading to abstract notions about what affects music may express. In a series of three experiments utilising three separate and iterative association tasks including a contextualisation with typical activities associated with specific music and affect terms, we identified the plausible affect terms and structures to capture the wide range of emotions expressed by music. The first experiment produced a list of frequently nominated affect terms (88 out of 647 candidates), and the second experiment established and confirmed multiple factor structures, ranging from 21, to 14, and 7 dimensions. The third experiment compared the terms with external datasets looking at discrete emotions and emotion dimensions, which verified the 7-factor structure and identified a compact 4-factor structure. These structures of affects expressed by music did not conform to music-induced emotion structures, nor could they be explained by basic emotions or affective circumplex. The established affect structures were largely positive and contained concepts such as “romantic” and “free”, and terms such as “in love”, “dreamy”, and “festive” that have rarely featured in past research.

Detection and genomic characterisation of foot-and-mouth disease virus serotypes circulating in Cameroon using environmental sampling

Deoxygenative photochemical alkylation of secondary amides enables a streamlined synthesis of substituted amines

Abstract Secondary amines are vital functional groups in pharmaceuticals, agrochemicals, and natural products, necessitating efficient synthetic methods. Traditional approaches, including N-monoalkylation and reductive amination, suffer from limitations such as poor chemoselectivity and complexity. Herein, we present a streamlined deoxygenative photochemical alkylation of secondary amides, enabling the efficient synthesis of α-branched secondary amines. Our method leverages triflic anhydride-mediated semi-reduction of amides to imines, followed by a photochemical radical alkylation step. This approach broadens the synthetic utility of amides, facilitating late-stage modifications of drug-like molecules and the synthesis of saturated N-substituted heterocycles. The pivotal role of flow technology in developing a scalable and robust process underscores the practicality of this method, significantly expanding the organic chemist’s toolbox for complex amine synthesis.

Reliability of artificial intelligence-driven markerless motion capture in gait analyses of healthy adults

The KinaTrax markerless motion capture system, used extensively in the analysis of baseball pitching and hitting, is currently being adapted for use in clinical biomechanics. In clinical and laboratory environments, repeatability is inherent to the quality of any diagnostic tool. The KinaTrax system was assessed on within- and between-session reliability for gait kinematic and spatiotemporal parameters in healthy adults. Nine subjects contributed five trials per session over three sessions to yield 135 unique trials. Each trial was comprised of a single bilateral gait cycle. Ten spatiotemporal parameters for each session were calculated and compared using the intraclass correlation coefficient (ICC), Standard Error of the Measurement (SEM), and minimal detectable change (MDC). In addition, seven kinematic waveforms were assessed from each session and compared using the coefficient of multiple determination (CMD). ICCs for between-session spatiotemporal parameters were lowest for left step time (0.896) and left cadence (0.894). SEMs were 0.018 (s) and 3.593 (steps/min) while MDCs were 0.050 (s) and 9.958 (steps/min). Between-session average CMDs for joint angles were large (0.969) in the sagittal plane, medium (0.554) in the frontal plane, and medium (0.327) in the transverse plane while average CMDs for segment angles were large (0.860), large (0.651), and medium (0.561), respectively. KinaTrax markerless motion capture system provides reliable spatiotemporal measures within and between sessions accompanied by reliable kinematic measures in the sagittal and frontal plane. Considerable strides are necessary to improve methodological comparisons, however, markerless motion capture poses a reliable application for gait analysis within healthy individuals.

A novel RRT*-Connect algorithm for path planning on robotic arm collision avoidance

Treadmill exercise prevents stress-induced anxiety-like behaviors via enhancing the excitatory input from the primary motor cortex to the thalamocortical circuit

Coordinated human-exoskeleton locomotion emerges from regulating virtual energy

Lower-limb exoskeletons have demonstrated great potential for gait rehabilitation in individuals with motor impairments; however, maintaining human-exoskeleton coordination remains a challenge. The coordination problem, referred to as any mismatch or asynchrony between the user’s intended trajectories and exoskeleton desired trajectories, leads to sub-optimal gait performance, particularly for individuals with residual motor ability. Here, we investigate the virtual energy regulator (VER)’s ability to generate coordinated locomotion in lower limb exoskeleton. Contribution: (1) In this paper, we experimented VER on a group of nine healthy individuals at different speeds (0.6 m / s − 0.85 m / s ) to study the resultant gait coordination and naturalness on a large group of users. (2) The resultant assisted gait is compared to the natural and passive (zero-torque exoskeleton) walking conditions in terms of muscle activities, kinematic, spatiotemporal and kinetic measures, and questionnaires. (3) Moreover, we presented the VER’s convergence proof considering the user contribution to the gait and introduced a metric to measure the user’s contribution to gait. (4) We also compared VER performance with the phase-based path controller in terms of muscle effort reduction and joint kinematics using three able-bodied individuals. Results: (1) The results from the VER demonstrate the emergence of natural, coordinated locomotion, resulting in an average muscle effort reduction ranging from 13.1% to 17.7% at different speeds compared to passive walking. (2) The results from VER revealed improvements in all indicators towards natural gait when compared to walking with a zero-torque exoskeleton, for instance, an enhancement in average knee extension ranging from 3.9 to 4.1 degrees. All indicators suggest that the VER preserves natural gait variability and user engagement in locomotion control. (3) Using VER also yields in 13.9%, 15.1%, and 7.0% average muscle effort reduction when compared to the phase-based path controller. (4) Finally, using our proposed metric, we demonstrated that the resultant locomotion limit cycle is a linear combination of human-intended limit cycle and the VER’s limit cycle. These findings may have implications for understanding how the central nervous system controls our locomotion.

Retraction Note: Association between cytochrome P4501A1 (CYP1A1) gene polymorphisms and the risk of renal cell carcinoma: a meta-analysis

Local polar order controls mechanical stress and triggers layer formation in Myxococcus xanthus colonies

Abstract Colonies of the social bacterium Myxococcus xanthus go through a morphological transition from a thin colony of cells to three-dimensional droplet-like fruiting bodies as a strategy to survive starvation. The biological pathways that control the decision to form a fruiting body have been studied extensively. However, the mechanical events that trigger the creation of multiple cell layers and give rise to droplet formation remain poorly understood. By measuring cell orientation, velocity, polarity, and force with cell-scale resolution, we reveal a stochastic local polar order in addition to the more obvious nematic order. Average cell velocity and active force at topological defects agree with predictions from active nematic theory, but their fluctuations are substantially larger than the mean due to polar active forces generated by the self-propelled rod-shaped cells. We find that M. xanthus cells adjust their reversal frequency to tune the magnitude of this local polar order, which in turn controls the mechanical stresses and triggers layer formation in the colonies.