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Chromatin loops (or chromatin interactions) are important elements of chromatin structures. Disruption of chromatin loops is associated with many diseases, such as cancer and polydactyly. A few methods, including ChIA-PET, HiChIP and PLAC-Seq, have been proposed to detect high-resolution, specific protein-mediated chromatin loops. With rapid progress in 3D genomic research, ChIA-PET, HiChIP and PLAC-Seq datasets continue to accumulate, and effective collection and processing for these datasets are urgently needed. Here, we developed a comprehensive, multispecies and specific protein-mediated chromatin loop database (ChromLoops, https://3dgenomics.hzau.edu.cn/chromloops), which integrated 1030 ChIA-PET, HiChIP and PLAC-Seq datasets from 13 species, and documented 1 491 416 813 high-quality chromatin loops. We annotated genes and regions overlapping with chromatin loop anchors with rich functional annotations, such as regulatory elements (enhancers, super-enhancers and silencers), variations (common SNPs, somatic SNPs and eQTLs), and transcription factor binding sites. Moreover, we identified genes with high-frequency chromatin interactions in the collected species. In particular, we identified genes with high-frequency interactions in cancer samples. We hope that ChromLoops will provide a new platform for studying chromatin interaction regulation in relation to biological processes and disease.
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Cromatina , Bases de Dados Genéticas , Cromatina/genética , Cromossomos , Genoma , Genômica , Sequências Reguladoras de Ácido Nucleico , Humanos , AnimaisRESUMO
Single-cell RNA sequencing (scRNA-seq) permits researchers to study the complex mechanisms of cell heterogeneity and diversity. Unsupervised clustering is of central importance for the analysis of the scRNA-seq data, as it can be used to identify putative cell types. However, due to noise impacts, high dimensionality and pervasive dropout events, clustering analysis of scRNA-seq data remains a computational challenge. Here, we propose a new deep structural clustering method for scRNA-seq data, named scDSC, which integrate the structural information into deep clustering of single cells. The proposed scDSC consists of a Zero-Inflated Negative Binomial (ZINB) model-based autoencoder, a graph neural network (GNN) module and a mutual-supervised module. To learn the data representation from the sparse and zero-inflated scRNA-seq data, we add a ZINB model to the basic autoencoder. The GNN module is introduced to capture the structural information among cells. By joining the ZINB-based autoencoder with the GNN module, the model transfers the data representation learned by autoencoder to the corresponding GNN layer. Furthermore, we adopt a mutual supervised strategy to unify these two different deep neural architectures and to guide the clustering task. Extensive experimental results on six real scRNA-seq datasets demonstrate that scDSC outperforms state-of-the-art methods in terms of clustering accuracy and scalability. Our method scDSC is implemented in Python using the Pytorch machine-learning library, and it is freely available at https://github.com/DHUDBlab/scDSC.
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Redes Neurais de Computação , Análise de Célula Única , Análise por Conglomerados , Perfilação da Expressão Gênica , RNA-Seq , Análise de Sequência de RNA/métodos , Análise de Célula Única/métodosRESUMO
MOTIVATION: Drug combination therapy has exhibited remarkable therapeutic efficacy and has gradually become a promising clinical treatment strategy of complex diseases such as cancers. As the related databases keep expanding, computational methods based on deep learning model have become powerful tools to predict synergistic drug combinations. However, predicting effective synergistic drug combinations is still a challenge due to the high complexity of drug combinations, the lack of biological interpretability, and the large discrepancy in the response of drug combinations in vivo and in vitro biological systems. RESULTS: Here, we propose DGSSynADR, a new deep learning method based on global structured features of drugs and targets for predicting synergistic anticancer drug combinations. DGSSynADR constructs a heterogeneous graph by integrating the drug-drug, drug-target, protein-protein interactions and multi-omics data, utilizes a low-rank global attention (LRGA) model to perform global weighted aggregation of graph nodes and learn the global structured features of drugs and targets, and then feeds the embedded features into a bilinear predictor to predict the synergy scores of drug combinations in different cancer cell lines. Specifically, LRGA network brings better model generalization ability, and effectively reduces the complexity of graph computation. The bilinear predictor facilitates the dimension transformation of the features and fuses the feature representation of the two drugs to improve the prediction performance. The loss function Smooth L1 effectively avoids gradient explosion, contributing to better model convergence. To validate the performance of DGSSynADR, we compare it with seven competitive methods. The comparison results demonstrate that DGSSynADR achieves better performance. Meanwhile, the prediction of DGSSynADR is validated by previous findings in case studies. Furthermore, detailed ablation studies indicate that the one-hot coding drug feature, LRGA model and bilinear predictor play a key role in improving the prediction performance. AVAILABILITY AND IMPLEMENTATION: DGSSynADR is implemented in Python using the Pytorch machine-learning library, and it is freely available at https://github.com/DHUDBlab/DGSSynADR.
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Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias , Humanos , Biologia Computacional/métodos , Combinação de Medicamentos , Neoplasias/tratamento farmacológico , Aprendizado de MáquinaRESUMO
BACKGROUND: Astroviruses (AstVs) are single-stranded RNA viruses that have been detected in a wide range of mammals and birds. They are associated with numerous interspecies transmissions and viral recombination events, posing a threat to human and animal health. METHODS: We collected 1,333 samples from wild animals, including bats, rodents, wild boars, and birds, from various states and cities in the Yunnan Province, China, between 2020 and 2023 to investigate the presence of AstVs. AstVs were detected using a polymerase chain reaction targeting the RdRp gene. Finally, the Molecular Evolutionary Genetics Analysis software was used to construct the phylogenetic tree. RESULTS: The overall positivity rate for AstVs was 7.12% in four species, indicating their widespread occurrence in the region. High genetic diversity among AstVs was observed in different animal species, suggesting the potential for interspecies transmission, particularly among rodents and birds. Additionally, we identified a novel AstV strain and, for the first time, provided information on the presence of bastroviruses in Yunnan, China. CONCLUSIONS: The widespread distribution and high genetic diversity of AstVs, along with the observed potential for interspecies transmission, highlight the importance of further investigation and surveillance in the region. The findings emphasize the need for increased attention to AstVs and their potential impact on human and animal health in Yunnan and other regions.
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Infecções por Astroviridae , Quirópteros , Vírus de RNA , Animais , Humanos , Animais Selvagens , Infecções por Astroviridae/epidemiologia , Infecções por Astroviridae/veterinária , Filogenia , China/epidemiologia , Mamíferos , RoedoresRESUMO
Male Japanese quails (Coturnix japonica) have been found to exhibit a three-phase metabolic change when subjected to prolonged fasting, during which basal thermogenesis is significantly reduced. A study had shown that there is a significant difference in the body temperature between male and female Japanese quails. However, whether female Japanese quails also show the same characteristic three-phase metabolic change during prolonged fasting and the underlying thermogenesis mechanisms associated with such changes are still unclear. In this study, female Japanese quails were subjected to prolonged starvation, and the body mass, basal metabolic rate (BMR), body temperature, mass of tissues and organs, body fat content, the state-4 respiration (S4R) and cytochrome c oxidase (CCO) activity in the muscle and liver of these birds were measured to determine the status of metabolic changes triggered by the starvation. In addition, the levels of glucose, triglyceride (TG) and uric acid, and thyroid hormones (T3 and T4) in the serum and the mRNA levels of myostatin (MSTN) and avian uncoupling protein (av-UCP) in the muscle were also measured. The results revealed the existence of a three-phase stage similar to that found in male Japanese quails undergoing prolonged starvation. Fasting resulted in significantly lower body mass, BMR, body temperature, tissues masses and most organs masses, as well as S4R and CCO activity in the muscle and liver. The mRNA level of av-UCP decreased during fasting, while that of MSTN increased but only during Phase I and II and decreased significantly during Phase III. Fasting also significantly lowered the T3 level and the ratio of T3/T4 in the serum. These results indicated that female Japanese quails showed an adaptive response in basal thermogenesis at multiple hierarchical levels, from organismal to biochemical, enzyme and cellular level, gene and endocrine levels and this integrated adjustment could be a part of the adaptation used by female quails to survive long-term fasting.
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Coturnix , Codorniz , Feminino , Masculino , Animais , Coturnix/metabolismo , Codorniz/metabolismo , Jejum/metabolismo , Termogênese , RNA Mensageiro/genéticaRESUMO
The monoamine transporters, including the serotonin transporter (SERT), dopamine transporter (DAT), and norepinephrine transporter (NET), are the therapeutic targets for the treatment of many neuropsychiatric disorders. Despite significant progress in characterizing the structures and transport mechanisms of these transporters, the regulation of their transport functions through dimerization or oligomerization remains to be understood. In the present study, we identified a conserved intramolecular ion-pair at the third extracellular loop (EL3) connecting TM5 and TM6 that plays a critical but divergent role in the modulation of dimerization and transport functions among the monoamine transporters. The disruption of the ion-pair interactions by mutations induced a significant spontaneous cross-linking of a cysteine mutant of SERT and an increase in cell surface expression but with an impaired specific transport activity. On the other hand, similar mutations of the corresponding ion-pair residues in both DAT and NET resulted in an opposite effect on their oxidation-induced dimerization, cell surface expression, and transport function. Reversible biotinylation experiments indicated that the ion-pair mutations slowed down the internalization of SERT but stimulated the internalization of DAT. In addition, cysteine accessibility measurements for monitoring SERT conformational changes indicated that substitution of the ion-pair residues resulted in profound effects on the rate constants for cysteine modification in both the extracellular and cytoplasmatic substrate permeation pathways. Furthermore, molecular dynamics simulations showed that the ion-pair mutations increased the interfacial interactions in a SERT dimer but decreased it in a DAT dimer. Taken together, we propose that the transport function is modulated by the equilibrium between monomers and dimers on the cell surface, which is regulated by a potential compensatory mechanism but with different molecular solutions among the monoamine transporters. The present study provided new insights into the structural elements regulating the transport function of the monoamine transporters through their dimerization.
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Cisteína , Proteínas da Membrana Plasmática de Transporte de Serotonina , Dimerização , Proteínas da Membrana Plasmática de Transporte de Serotonina/genética , Biotinilação , Membrana Celular , Proteínas da Membrana Plasmática de Transporte de Norepinefrina , PolímerosRESUMO
DNA methylation plays an important role in gene regulation and genomic stability. However, large DNA hypomethylated regions known as DNA methylation valleys (DMVs) or canyons have also been suggested to serve unique regulatory functions, largely unknown in rice (Oryza sativa). Here, we describe the DMVs in rice seedlings, which were highly enriched with developmental and transcription regulatory genes. Further detailed analysis indicated that grand DMVs (gDMVs) might be derived from nuclear integrants of organelle DNA (NORGs). Furthermore, Domains Rearranged Methylase 2 (OsDRM2) maintained DNA methylation at short DMV (sDMV) shores. Epigenetic maps indicated that sDMVs were marked with H3K4me3 and/or H3K27me3, although the loss of DNA methylation had a negligible effect on histone modification within these regions. In addition, we constructed H3K27me3-associated interaction maps for homozygous T-DNA insertion mutant of the gene (osdrm2) and wild type (WT). From a global perspective, most (90%) compartments were stable between osdrm2 and WT plants. At a high resolution, we observed a dramatic loss of long-range chromatin loops in osdrm2, which suffered an extensive loss of non-CG (CHG and CHH, H = A, T, or C) methylation. From another viewpoint, the loss of non-CG methylation at sDMV shores in osdrm2 could disrupt H3K27me3-mediated chromatin interaction networks. Overall, our results demonstrated that DMVs are a key genomic feature in rice and are precisely regulated by epigenetic modifications, including DNA methylation and histone modifications. OsDRM2 maintained DNA methylation at sDMV shores, while OsDRM2 deficiency strongly affected three-dimensional (3D) genome architectures.
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Metilação de DNA , Oryza , Metilação de DNA/genética , Cromatina/genética , Histonas/genética , Histonas/metabolismo , Oryza/genética , Oryza/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Metiltransferases/genética , DNA , Regulação da Expressão Gênica de Plantas/genéticaRESUMO
Computer vision-based displacement measurement techniques are increasingly used for structural health monitoring. However, the vision sensors employed are easily affected by optical turbulence when capturing images of the structure, resulting in displacement measurement errors that significantly reduce the accuracy required in engineering applications. Hence, this paper develops a multi-measurement point method to address this problem by mitigating optical-turbulence errors with spatial randomness. Then, the effectiveness of the proposed method in mitigating optical-turbulence errors is verified by static target experiments, in which the RMSE correction rate can reach up to 82%. Meanwhile, the effects of target size and the number of measurement points on the proposed method are evaluated, and the optimal target design criteria are proposed to improve our method's performance in mitigating optical-turbulence errors under different measurement conditions. Additionally, extensive dynamic target experiments reveal that the proposed method achieves an RMSE correction rate of 69% after mitigating the optical-turbulence error. The experimental results demonstrate that the proposed method improves the visual displacement measurement accuracy and retains the detailed information of the displacement measurement results.
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The COVID-19 pandemic has placed the notion of "travel shaming" under the spotlight-tourists are concerned about being criticized for traveling during the pandemic. Yet the broader idea of travel-induced shaming, conceptualized as ethics-based evaluations in this paper, has not drawn much attention as consequence-based assessments in travel-related risk research. This paper presents two studies revealing a) how ethics- and consequence-based risk evaluations influence individuals' travel attitudes/intentions and b) how message framing about responsible travel affects travel shame and individuals' intentions to travel responsibly. Using structural equation modeling, Study 1 suggests that consequence- and ethics-based evaluations play key roles in predicting travelers' attitudes/intentions to travel. Moreover, social trust and self-efficacy significantly affect both types of risk evaluations. Study 2 adopts an experimental design and shows that, compared with loss-framed and controlled message conditions, gain-framed messaging can reduce travel shame and encourage tourists to travel responsibly. Theoretical and practical implications were discussed.
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The microenvironment tuning of Ni species, a promising non-precious catalyst, is significant in the energy and environmentally relevant urea electro-oxidation reaction (UOR). Herein, we found that the high-valent Ni species induced by the inactive MoO2 in mixed nanocrystals of NiO/MoO2 were effective for urea oxidation. The redox interaction of MoO2 and NiO revealed by the spectroscopic analysis well supported the formation of high-valent Ni species and the changes in the surface chemical state. High catalytic activity and stability for urea oxidation were observed by a series of electrochemical measures compared to the counterpart catalysts of MoO2 and NiO. The optimal NiO/MoO2 hybrid catalyst showed a UOR activity of 73.1 mA cm-2 at 1.50 V, which was about 12-fold that of the NiO catalyst. In addition, largely improved catalytic kinetics and catalytic stability for UOR were also demonstrated. Because of the inactive activity of MoO2 and the low performance of NiO, the largely improved preference can be affirmatively attributed to the efficient catalytic synergism of NiO/MoO2 in the mixed nanocrystals. The current finding clarifies the catalytic promotion effect of the inactive Mo species on Ni-based catalysts for urea oxidation, which would be instructive for Ni/Mo-relevant catalyst development.
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Níquel , Ureia , Ureia/análise , Ureia/química , Níquel/química , Catálise , OxirreduçãoRESUMO
Marine bacteriophages frequently possess auxiliary metabolic genes (AMGs) that accelerate host metabolism during phage infection. The significance of AMGs in phage infecting the ecologically important Roseobacter clade, found predominantly in marine environments, remains to be determined. Here, we analysed the distribution and genomic context of 180 AMGs, annotated into 20 types, across 50 roseophage genomes. Roseophages share seven high-frequency AMGs (trx, grx, RNR, thyX, DCD, phoH, and mazG)ï¼ most of them involved in the nucleotide biosynthesis pathway that represent conserved intra and inter operational taxonomic units (OTUs), and share ≥97% full-length DNA sequence similarity. Sporadic AMGs (dUTPase, lexA, degS, Que, NAPRT, AHL, pcnB, ctrA, RTX, RNR-nrdA, RNR-nrdE, wclP, and flgJ), present in only one or two OTUs, show high functional diversity. The roseophage AMG repertoire weakly correlates with environmental factors, while host range partially explains the sporadic AMG distribution. Locally co-linear blocks distribution index (LDI) analysis indicated that high-frequency roseopodovirus AMGs are restricted to particular genomic islands, possibly originating from limited historical acquisition events. Low-frequency roseopodovirus AMGs and all roseosiphovirus AMGs have high LDI values, implying multiple historical acquisition events. In summary, roseophages have acquired a range of AMGs through horizontal gene transfer, and the forces shaping the evolution of roseophages are described.
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Genoma Viral , Roseobacter , Genoma Viral/genética , Genômica , Filogenia , Água do MarRESUMO
Rhizoma Drynariae, the dried rhizome of Drynaria fortunei (Kunze), is rich in flavonoids and has varieties of pharmacological activities. To optimize the extract conditions for bioactive flavonoids, a response surface methodology (RSM) was utilized to assess the effects of three independent variables (liquid-to-solid ratio (mL/g), extract temperature (°C) and ethanol concentration (%) on the total flavonoids content (TFC). To test the chelation with metal ion, the UV-visible spectrophotometer was used to detect metal ion chelation of extracted flavonoids. Regression analysis displayed a good fit of the experimental data. The optimal condition was liquid-to-solid ratio with 50:1, extract temperature with 80 °C and ethanol concentration with 40.22%. The total flavonoids had a better chelation with metal ions Cu2+, Fe2+, Fe3+ than Zn2+. These results suggested that the model employed is suitable and the application of RSM in optimizing the extract conditions is successful. The experimental values were in fine agreement (the yield 24.05±0.69mg/g) with predicted values. The total flavonoids from the extract presented good chelation against four metal ions (Cu2+, Zn2+, Fe2+ and Fe3+), which provided a good evidence for Alzheimer's disease treatments.
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Técnicas de Química Analítica/métodos , Flavonoides/química , Extratos Vegetais/química , Polypodiaceae , Rizoma , Quelantes/farmacologia , Química Farmacêutica , Cobre , Etanol , Compostos Férricos , Compostos Ferrosos , Flavonoides/farmacologia , Raízes de Plantas , Solventes , Temperatura , ZincoRESUMO
OBJECTIVE: To evaluate the effects of Guasha therapy on the rating of perceived exertion (RPE) scale score, and heart rate variability (HRV). METHODS: A randomized controlled trial of Guasha (skin scraping) was compared with a sham scraping group and control group. Sixteen sessions within an 8-week period were completed. Sixty-five male weightlifters who had undergone normal weightlifting training for a mean of 5 years before study commencement were recruited. The RPE scale score of "snatch", "clean and jerk" maneuvers (85% of one-repetition maximum), and HRV were measured before and after the intervention. RESULTS: The RPE scale score for snatch, clean and jerk were reduced significantly after intervention in the Guasha group and sham group. However, there was a significant difference in the low frequency (LF) domain and LF/high frequency (HF) ratio (P < 0.05): the LF domain decreased, and the LF/HF ratio decreased. CONCLUSION: Guasha could be used to reduce the RPE scale score, and increase the response to HRV. Guasha could be considered as an alternative to some types of recovery from sports training.
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Medicamentos de Ervas Chinesas/administração & dosagem , Frequência Cardíaca/efeitos dos fármacos , Esforço Físico/efeitos dos fármacos , Levantamento de Peso/fisiologia , Adulto , Humanos , Masculino , Adulto JovemRESUMO
RNA interference (RNAi) is a process of eukaryotic posttranscriptional gene silencing that functions in antiviral immunity in plants, nematodes, and insects. However, recent studies provided strong supports that RNAi also plays a role in antiviral mechanism in mammalian cells. To combat RNAi-mediated antiviral responses, many viruses encode viral suppressors of RNA silencing (VSR) to facilitate their replication. VSRs have been widely studied for plant and insect viruses, but only a few have been defined for mammalian viruses currently. We identified a novel VSR from coronaviruses, a group of medically important mammalian viruses including Severe acute respiratory syndrome coronavirus (SARS-CoV), and showed that the nucleocapsid protein (N protein) of coronaviruses suppresses RNAi triggered by either short hairpin RNAs or small interfering RNAs in mammalian cells. Mouse hepatitis virus (MHV) is closely related to SARS-CoV in the family Coronaviridae and was used as a coronavirus replication model. The replication of MHV increased when the N proteins were expressed in trans, while knockdown of Dicer1 or Ago2 transcripts facilitated the MHV replication in mammalian cells. These results support the hypothesis that RNAi is a part of the antiviral immunity responses in mammalian cells. IMPORTANCE RNAi has been well known to play important antiviral roles from plants to invertebrates. However, recent studies provided strong supports that RNAi is also involved in antiviral response in mammalian cells. An important indication for RNAi-mediated antiviral activity in mammals is the fact that a number of mammalian viruses encode potent suppressors of RNA silencing. Our results demonstrate that coronavirus N protein could function as a VSR through its double-stranded RNA binding activity. Mutational analysis of N protein allowed us to find out the critical residues for the VSR activity. Using the MHV-A59 as the coronavirus replication model, we showed that ectopic expression of SARS-CoV N protein could promote MHV replication in RNAi-active cells but not in RNAi-depleted cells. These results indicate that coronaviruses encode a VSR that functions in the replication cycle and provide further evidence to support that RNAi-mediated antiviral response exists in mammalian cells.
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Vírus da Hepatite Murina/genética , Proteínas do Nucleocapsídeo/genética , Interferência de RNA , RNA Interferente Pequeno/genética , Síndrome Respiratória Aguda Grave/genética , Sequência de Aminoácidos , Animais , Proteínas Argonautas/genética , Sequência de Bases , Linhagem Celular , Coronavirus/genética , Coronavirus/imunologia , Proteínas do Nucleocapsídeo de Coronavírus , RNA Helicases DEAD-box/genética , Células HEK293 , Humanos , Células L , Camundongos , Vírus da Hepatite Murina/crescimento & desenvolvimento , Vírus da Hepatite Murina/imunologia , Proteínas do Nucleocapsídeo/biossíntese , Ribonuclease III/genética , Alinhamento de Sequência , Síndrome Respiratória Aguda Grave/virologiaRESUMO
[Purpose] This study was to examine the effects of 12 weeks of Tai Chi (TC) exercise on antioxidant capacity, and DNA damage/repair in young females who did not perform regular physical exercise. [Subjects and Methods] Ten female students from a Chinese university voluntarily participated in this program. All of them practiced the 24-form simplified Tai Chi, 5 times weekly, for 12 weeks. Plasma levels of superoxide dismutase (SOD), glutathione peroxidase (GPx), malondialdehyde (MDA), glutathione (GSH), hydroxyl radical inhibiting capacity (OH·-IC), 8-hydroxy-2'-deoxyguanosine (8-OHdG), and 8-oxoguanine DNA glycosylase (OGG1) were measured at 0, 8, and 12 weeks. Heart rate (HR) was monitored during the last set of the training session at 4, 8, and 12 weeks. [Results] Plasma SOD and OH·-IC levels were increased at 8 and 12 weeks compared to the baseline (0 weeks). Gpx and GSH levels did not change significantly throughout the study period. The plasma MDA level was decreased significantly at 8 weeks but not at 12 weeks compared to the baseline value. While the plasma 8-OHdG level did not change throughout the study period, the plasma OGG1 level was significantly increased at 8 and 12 weeks compared to the baseline value. [Conclusion] TC practice for 12 weeks efficiently improved the oxidative stress response in young females who did not perform regular physical exercise. The TC exercise also increased the DNA repairing capacity.
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About 80% of stroke patients have hand motor dysfunction, and wearing finger rehabilitation machinery can enable patients to carry out efficient passive rehabilitation training independently. At present, many typical finger rehabilitation machines have been developed, and clinical experiments have confirmed the effectiveness of mechanically assisted finger rehabilitation. In this paper, the finger rehabilitation machinery will be classified in the actuation mode, and the terminal traction drive/motor drive/spring drive/rope drive/memory alloy drive/electroactive material drive/hydraulic drive/pneumatic drive technology and its typical applications are analyzed. Study the structure, control methods, overlap between mechanical bending nodes and finger joints, training modes, response speed, and driving force of various types of finger rehabilitation machinery. The advantages and disadvantages of various actuation methods of finger rehabilitation machinery are summarized. Finally, the difficulties and opportunities faced by the future development of finger rehabilitation machinery are prospected. In general, with the continuous improvement of quality of life, stroke patients need flexible, segmented control, accurate bending, multi-training mode, fast response, and good driving force finger rehabilitation machinery. This will also be a future hot research direction.
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Sodium butyrate (SB) is a histone deacetylase inhibitor that can induce changes in gene expression and secondary metabolite titers by inhibiting histone deacetylation. Our preliminary analysis also indicated that SB significantly enhanced the biosynthesis of carotenoids in the Rhodotorula glutinis strain YM25079, although the underlying regulatory mechanisms remained unclear. Based on an integrated analysis of transcriptomics and metabolomics, this study revealed changes in cell membrane stability, DNA and protein methylation levels, amino acid metabolism, and oxidative stress in the strain YM25079 under SB exposure. Among them, the upregulation of oxidative stress may be a contributing factor for the increase in carotenoid biosynthesis, subsequently enhancing the strain resistance to oxidative stress and maintaining the membrane fluidity and function for normal cell growth. To summarize, our results showed that SB promoted carotenoid synthesis in the Rhodotorula glutinis strain YM25079 and increased the levels of the key metabolites and regulators involved in the stress response of yeast cells. Additionally, epigenetic modifiers were applied to produce fungal carotenoid, providing a novel and promising strategy for the biosynthesis of yeast-based carotenoids.
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Purpose: To address the application requirements of soft actuators in rehabilitation training gloves, and in combination with ergonomic requirements, we designed a segmented soft actuator with bending and elongation modules. This actuator can achieve independent or coupled movements of the finger joints. Methods: A finite element model of the joint actuator was established to compare the driving performance of actuators with different structural forms. Numerical calculations were used to analyze the effects of structural size parameters on the bending characteristics and end output force of the actuator. The design was then refined based on these analyses. Results: The joint actuator designed in this study demonstrated a 71% increase in bending angle compared to the standard fast pneumatic network structure. Key factors affecting the driving performance include the thickness of the constraint layer, the inner wall thickness of the chamber, chamber height, chamber width, chamber spacing, chamber length, and the number of chambers. After improvements, the bending angle of the joint actuator increased by 60.6%, and the output force increased by 145.9%, indicating significant improvement. Conclusion: This study designed and improved a soft actuator for hand rehabilitation training, achieving independent and coupled joint movements. The bending angle, bending shape, and joint driving force of the soft actuator meet the requirements for finger rehabilitation training.
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Multi-boron-embedded multiple resonance thermally activated delayed fluorescence (MR-TADF) emitters show promise for achieving both high color-purity emission and high exciton utilization efficiency. However, their development is often impeded by a limited synthetic scope and excessive molecular weights, which challenge material acquisition and organic light-emitting diode (OLED) fabrication by vacuum deposition. Herein, we put forward a BâN covalent bond-involved π-extension strategy via post-functionalization of MR frameworks, leading to the generation of high-order B/N-based motifs. The structurally and electronically extended π-system not only enhances molecular rigidity to narrow emission linewidth but also promotes reverse intersystem crossing to mitigate efficiency roll-off. As illustrated examples, ultra-narrowband sky-blue emitters (full-width at half-maximum as small as 8 nm in n-hexane) have been developed with multi-dimensional improvement in photophysical properties compared to their precursor emitters, which enables narrowband OLEDs with external quantum efficiencies (EQEmax) of up to 42.6%, in company with alleviated efficiency decline at high brightness, representing the best efficiency reported for single-host OLEDs. The success of these emitters highlights the effectiveness of our molecular design strategy for advanced MR-TADF emitters and confirms their extensive potential in high-performance optoelectronic devices.
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Cellulose is a sustainable natural polymer material that has found widespread application in transformers and other power equipment because of its excellent electrical and mechanical performance. However, the utility of cellulose materials has been limited by the challenge of balancing heat resistance with flexibility. On the basis of the preliminary research conducted by the research team, further proposals have been put forward for a method involving disk milling to create a "micro-nanocollaboration" network for the fabrication of flexible, high-temperature-resistant, and ultrafine fiber-based cellulose insulating films. The resulting full-component cellulose films exhibited impressive properties, including high tensile strength (22 MPa), flexibility (92-263 mN), remarkable electrical breakdown strength (39 KV/mm), and volume resistivity that meets the standards for insulation materials (4.92 × 1011 Ω·m). These results demonstrate that the proposed method can produce full-component cellulose insulation films that offer both exceptional flexibility and high-temperature resistance.