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Rechargeable lithium-ion batteries are integral to contemporary energy storage, yet current anode material systems struggle to meet the increasing demand for extended range capabilities. This work introduces a novel composite anode material composed of one-dimensional 2H-phase tin disulfide (SnS2) nanoribbons enclosed within cavities of single-walled carbon nanotubes (SnS2@SWCNTs), achieved through precise atomic engineering. Employing aberration-corrected transmission electron microscopy, we precisely elucidated the crystal structure of SnS2 within the confines of the SWCNTs. This deliberate design effectively addresses the inherent limitations of SnS2 as a lithium-ion anode material, including its low electrical conductivity, considerable volume expansion effects, and unstable solid electrolyte interface membrane. Testing confirmed that SnS2 transforms into the Li5Sn2 alloy phase after full lithiation and back to SnS2 after delithiation, showing excellent reversibility. The composite also benefits from edge effects, improving lithium storage through stronger binding and lower migration barriers, which were supported by calculations. This pioneering work advances high-performance anode materials for applications.
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Bismuth oxyselenide (Bi2O2Se), an emerging 2D semiconductor material, has garnered substantial attention owing to its remarkable properties, including air stability, elevated carrier mobility, and ultrafast optical response. In this study, we conduct a comparative analysis of electron excitation and relaxation processes in monolayer and bilayer Bi2O2Se. Our findings reveal that monolayer Bi2O2Se exhibits parity-forbidden transitions between the band edges at the Γ point, whereas bilayer Bi2O2Se demonstrates parity activity, providing the bilayer with an advantage in light absorption. Employing nonadiabatic molecular dynamics simulations, we uncover a two-stage hot-electron relaxation process-initially fast followed by slow-in both monolayer and bilayer Bi2O2Se within the conduction band. Despite the presence of weak nonadiabatic coupling between the CBM + 1 and CBM, limiting hot electron relaxation, the monolayer displays a shorter relaxation time due to its higher phonon-coupled frequency and smaller energy difference. Our investigation sheds light on the layer-specific excitation properties of 2D Bi2O2Se layered materials, providing crucial insights for the strategic design of photonic devices utilizing 2D materials.
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A widely used type II pyrethroid pesticide cypermethrin (CYP) is one of endocrine disrupting chemicals (EDCs) with anti-androgenic activity to induce male reproductive toxicology. However, the mechanisms have not been fully elucidated. This study was to explore the effects of CYP on apoptosis of mouse Sertoli cells (TM4) and the roles of endoplasmic reticulum (ER)-mitochondria coupling involving 1,4,5-trisphosphate receptor type1-glucose-regulated protein 75-voltage-dependent anion channel 1 (IP3R1-GRP75-VDAC1). TM4 were cultured with different concentrations of CYP. Flow cytometry, calcium (Ca2+) fluorescent probe, transmission electron microscopy and confocal microscopy, and western blot were to examine apoptosis of TM4, mitochondrial Ca2+, ER-mitochondria coupling, and expressions of related proteins. CYP was found to increase apoptotic rates of TM4 significantly. CYP was shown to significantly increase expressions of cleaved caspase-3, cleaved poly ADP-ribose polymerase (PARP). Concentration of mitochondrial Ca2+ was increased by CYP treatment significantly. CYP significantly enhanced ER-mitochondria coupling. CYP was shown to increase expressions of IP3R, Grp75 and VDAC1 significantly. We suggest that CYP induces apoptosis in TM4 cells by facilitating mitochondrial Ca2+ overload regulated by ER-mitochondria coupling involving IP3R1-GRP75-VDAC1. This study identifies a novel mechanism of CYP-induced apoptosis in Sertoli cells.
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Proteínas HSP70 de Choque Térmico , Proteínas de la Membrana , Piretrinas , Células de Sertoli , Ratones , Animales , Masculino , Células de Sertoli/metabolismo , Mitocondrias , Retículo Endoplásmico/metabolismo , Piretrinas/toxicidad , Apoptosis , Calcio/metabolismoRESUMEN
This study developed a machine learning-based force field for simulating the bcc-hcp phase transitions of iron. By employing traditional molecular dynamics sampling methods and stochastic surface walking sampling methods, combined with Bayesian inference, we construct an efficient machine learning potential for iron. By using SOAP descriptors to map structural data, we find that the machine learning force field exhibits good coverage in the phase transition space. Accuracy evaluation shows that the machine learning force field has small errors compared to DFT calculations in terms of energy, force, and stress evaluations, indicating excellent reproducibility. Additionally, the machine learning force field accurately predicts the stable crystal structure parameters, elastic constants, and bulk modulus of bcc and hcp phases of iron, and demonstrates good performance in predicting higher-order derivatives and phase transition processes, as evidenced by comparisons with DFT calculations and existing experimental data. Therefore, our study provides an effective tool for investigating the phase transitions of iron using machine learning methods, offering new insights and approaches for materials science and solid-state physics research.
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Cypermethrin (CYP) has been identified as one kind of endocrine-disrupting chemicals (EDCs) to induce male reproduction damage. This study aimed to investigate the effects and mechanisms of miR-30a-5p on CYP induced apoptosis of TM4 mouse Sertoli cells in vitro. In the present study, 0 µM, 10 µM, 20 µM, 40 µM and 80 µM CYP were used to treat TM4 cells for 24 h. The apoptosis of TM4 cells, the expression level of miR-30a-5p, the protein expressions and the interaction between miR-30a-5p and KLF9 were detected by flow cytometry, quantitative Real-Time PCR, Western blot and luciferase reporter assays. CYP induced apoptosis of TM4 cells, inhibited expression of miR-30a-5p in TM4 cells, and overexpression of miR-30a-5p partially recovered CYP induced cells apoptosis. Furthermore, KLF9 was a potential downstream target of miR-30a-5p predicted by publicly available databases. KLF9 expression level in TM4 cells was significantly elevated after treatment with CYP, and the induction was inhibited by miR-30a-5p mimics transfection. Meanwhile, dual-luciferase reporter assay demonstrated that miR-30a-5p directly targeted KLF9-3'UTR. Moreover, in the presence of CYP, the apoptosis regulator p53 expression was also increased in TM4 cells. Overexpression miR-30a-5p or down-regulation of KLF9 both attenuated the induction of CYP on p53 expression. Overall, the present study demonstrated that miR-30a-5p regulated CYP induced TM4 cells apoptosis by targeting KLF9/p53 axis.
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MicroARNs , Animales , Ratones , Masculino , MicroARNs/genética , Células de Sertoli/metabolismo , Proteína p53 Supresora de Tumor/genética , Línea Celular Tumoral , Proliferación Celular , ApoptosisRESUMEN
INTRODUCTION: This study aimed to understand the transcriptome characteristics of the skeletal muscle of elderly (EL) men with metabolic syndrome (MS) and to find the hub genes and insight into the molecular mechanisms of skeletal muscle in the occurrence and development of MS. METHODS: In this study, the limma package of R software was used to analyze the differentially expressed genes in the skeletal muscle of healthy young (YO) adult men, healthy EL men, and EL men diagnosed with MS (SX) for at least 10 years. Bioinformatics methods, such as GO enrichment analysis, KEGG enrichment analysis, and gene interaction network analysis, were used to explore the biological functions of differentially expressed genes, and weighted gene coexpression network analysis (WGCNA) was used to cluster differentially expressed genes into modules. RESULTS: Among the YO group, EL group, and SX group, 65 co-differentially expressed genes were found maybe regulated by age factor and MS factor. Those co-differentially expressed genes were enriched into 25 biological process terms and 3 KEGG pathways. Based on the WGCNA results, a total of five modules were identified. Fifteen hub genes may play an essential role in regulating the function of skeletal muscle of EL men with MS. CONCLUSIONS: 65 differentially expressed genes and 5 modules may regulate the function of skeletal muscle of EL men with MS, among which fifteen hub genes may play an essential role in the occurrence and development of MS.
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Síndrome Metabólico , Transcriptoma , Masculino , Humanos , Anciano , Síndrome Metabólico/genética , Perfilación de la Expresión Génica , Redes Reguladoras de Genes , Músculo Esquelético/metabolismoRESUMEN
Using density functional theory and the non-equilibrium Green's function method, we theoretically investigated the structures, stabilities, electronic properties, and the direct-current (DC) and alternating-current (AC) transport properties of the line defects in two-dimensional material ß12-borophene. Our results suggest that there exist six line defects that can enhance the stability of ß12-borophene and the line defects have profound influences on the electronic structure of ß12-borophene. Along the zigzag direction, the line defects can change the atomic orbital components of the Dirac cones in perfect ß12-borophene, but the line defects along the armchair direction have complicated influences on the Dirac cones. In the case of DC transport, some of the line defects lead to the constant DC phenomenon and the negative differential resistance effect, and enhance the DC conductances since the line defects exhibit typical one-dimensional characteristics. In the case of AC transport, some of the line defects enhance the AC conductances in the medium-frequency and high-frequency ranges through the photon-assisted tunneling effect. The microscopic mechanisms of the enhanced DC and AC conductances are different. In addition, for a low-frequency range, the equivalent circuits of ß12-borophene and the line defects were also suggested, which will be beneficial for designing borophene-based functional nanodevices.
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OBJECTIVE: In the previous study, we identified bone morphogenetic protein 4 (BMP4) responsible for non-syndromic cleft lip with or without cleft palate (NSCL/P). We aimed to elucidate the effects and mechanisms of BMP4 on epithelial-mesenchymal transition (EMT) through Smad1 signaling pathway to be involved in NSCL/P. METHODS: The human oral epidermoid carcinoma cells (KBs) were transfected with plasmids or small interfering RNA (siRNA) to build the models. The migration of the cells was evaluated by transwell assay. Western blotting and quantitative real-time reverse transcription-polymerase chain reaction (qRT-PCR) were used to detect the expressions of BMP4, E-cadherin, N-cadherin, EMT-related transcription factors snal1 and snal2, matrix metalloproteinase 2 (MMP2), MMP9, Smad1, and phosphorylated Smad1. RESULTS: In the overexpression group, the migration number of cells was increased significantly. The protein expression of E-cadherin was decreased significantly, while the protein expression level of the N-cadherin was increased significantly. The protein and mRNA expressions of MMP2, MMP9, snal1, and snal2 were significantly higher. The expression level of Smad1 was not significantly changed, while the phosphorylation of Smad1 was significantly increased. In the BMP4-siRNA group, the migrating number cells was significantly decreased. The protein expression of E-cadherin was increased significantly, while the expression of N-cadherin was significantly decreased. The protein and mRNA expressions of MMP2, MMP9, snal1, and snal2 were significantly lower than that of the control group. The expressions of Smad1 and phosphorylation of Smad1 were not significantly changed. CONCLUSIONS: BMP4 enhances cell migration and promotes cell EMT through Smad1 signaling pathway. Abnormal BMP4 mediates migration and EMT through other relevant signaling pathways resulting in NSCL/P. The study provides new insight into the mechanisms of NSCL/P associated with BMP4.n.
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Proteína Morfogenética Ósea 4 , Labio Leporino , Fisura del Paladar , Humanos , Proteína Morfogenética Ósea 4/genética , Proteína Morfogenética Ósea 4/metabolismo , Cadherinas/genética , Labio Leporino/genética , Labio Leporino/complicaciones , Fisura del Paladar/genética , Fisura del Paladar/complicaciones , Transición Epitelial-Mesenquimal , Metaloproteinasa 2 de la Matriz , Metaloproteinasa 9 de la Matriz , Hueso Paladar , ARN Mensajero , ARN Interferente PequeñoRESUMEN
BACKGROUND: Tetralogy of Fallot (TOF) is the most common cyanotic congenital heart disease in clinical practice. It is mainly due to cardiovascular hypoplasia during embryonic development. The study aimed to find the etiology of TOF. METHODS: Through the mRNA expression profile analysis of the GSE35776 dataset, differentially expressed genes (DEGs) were found, and the functional analysis and protein-protein interaction (PPI) network analysis were then performed on DEGs. Likewise, the hub genes and functional clusters of DEGs were analyzed using the PPI network. Differentially expressed miRNAs were analyzed from the GSE35490 dataset, followed by miRNet predicted transcription factors (TFs) and target genes. The key TF-miRNA-gene interaction mechanism was explored through the found significant difference between genes and target genes. RESULTS: A total of 191 differentially expressed genes and 57 differentially expressed miRNAs were identified. The main mechanisms involved in TOF were mitochondria-related and energy metabolism- related molecules and pathways in GO and KEGG analysis. This discovery was identical in TFs and target genes. The key miRNAs, hsa-mir-16 and hsa-mir-124, were discovered by the Venn diagram. A co-expression network with the mechanism of action centered on two miRNAs was made. CONCLUSION: Hsa-mir-16 and hsa-mir-124 are the key miRNAs of TOF, which mainly regulate the expression of NT5DC1, ECHDC1, HSDL2, FCHO2, and ACAA2 involved in the conversion of ATP in the mitochondria and the metabolic rate of fatty acids (FA). Our research provides key molecules and pathways into the etiology of TOF, which can be used as therapeutic targets.
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MicroARNs , Tetralogía de Fallot , Humanos , Tetralogía de Fallot/genética , Perfilación de la Expresión Génica , Biología Computacional , MicroARNs/genética , Regulación Neoplásica de la Expresión Génica , Hidroxiesteroide Deshidrogenasas/genéticaRESUMEN
Cypermethrin (CP) exhibits anti-androgenic effects through antagonism on androgen receptor (AR) activation. This study was to identify whether AR-mediated disabled 2 interacting protein (DAB2IP)/phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT) pathway was involved in CP-induced mouse Sertoli cells (TM4) proliferation disorder. Real-Time Cell Analysis-iCELLigence system was to measure cell proliferation. Bioinformatic analyses were performed to identify AR-regulated genes. Quantitative Real-Time PCR and western blot were to detect the genes and proteins levels in AR-mediated DAB2IP/PI3K/AKT pathway. Results showed CP suppressed TM4 proliferation and the expression of AR. Activation of AR restored the inhibition efficacy of CP on TM4 proliferation. AR regulated DAB2IP expression and phosphorylation levels of PI3K and AKT in CP-exposed TM4 cells. In addition, knockdown of DAB2IP alleviated the inhibition efficacy of CP on cell proliferation and phosphorylation of PI3K and AKT. Taken together, AR was a modulator in CP-induced inhibition of Sertoli cells proliferation by negatively regulating DAB2IP/PI3K/AKT signaling pathway. The study may provide a new insight for the mechanisms of male reproductive toxicity induced by CP.
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BACKGROUND: Neurodegenerative diseases, such as Alzheimer's disease patients (AD), Huntington's disease (HD) and Parkinson's disease (PD), are common causes of morbidity, mortality, and cognitive impairment in older adults. OBJECTIVE: We aimed to understand the transcriptome characteristics of the cortex of neurodegenerative diseases and to provide an insight into the target genes of differently expressed microRNAs in the occurrence and development of neurodegenerative diseases. METHODS: The Limma package of R software was used to analyze GSE33000, GSE157239, GSE64977 and GSE72962 datasets to identify the differentially expressed genes (DEGs) and microRNAs in the cortex of neurodegenerative diseases. Bioinformatics methods, such as GO enrichment analysis, KEGG enrichment analysis and gene interaction network analysis, were used to explore the biological functions of DEGs. Weighted gene co-expression network analysis (WGCNA) was used to cluster DEGs into modules. RNA22, miRDB, miRNet 2.0 and TargetScan7 databases were performed to predict the target genes of microRNAs. RESULTS: Among 310 Alzheimer's disease (AD) patients, 157 Huntington's disease (HD) patients and 157 non-demented control (Con) individuals, 214 co-DEGs were identified. Those co-DEGs were filtered into 2 different interaction network complexes, representing immune-related genes and synapserelated genes. The WGCNA results identified five modules: yellow, blue, green, turquoise, and brown. Most of the co-DEGs were clustered into the turquoise module and blue module, which respectively regulated synapse-related function and immune-related function. In addition, human microRNA-4433 (hsa-miR-4443), which targets 18 co-DEGs, was the only 1 co-up-regulated microRNA identified in the cortex of neurodegenerative diseases. CONCLUSION: 214 DEGs and 5 modules regulate the immune-related and synapse-related function of the cortex in neurodegenerative diseases. Hsa-miR-4443 targets 18 co-DEGs and may be a potential molecular mechanism in neurodegenerative diseases' occurrence and development.
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Enfermedad de Alzheimer , Enfermedad de Huntington , MicroARNs , Enfermedades Neurodegenerativas , Humanos , Anciano , Redes Reguladoras de Genes , Perfilación de la Expresión Génica/métodos , Enfermedad de Huntington/genética , Enfermedades Neurodegenerativas/genética , Enfermedad de Alzheimer/genética , MicroARNs/genética , Biología Computacional/métodos , Factores de RiesgoRESUMEN
Sodium ion technology is increasingly investigated as a low-cost solution for grid storage applications. Among the reported cathode materials for sodium-ion batteries, Na3V2(PO4)2FO2 is considered as one of the most promising materials due to its high operation voltage and good cyclability. Here, the de-sodiumization process of Na3V2(PO4)2FO2 has been systematically examined using first-principles calculations to uncover the fundamental questions at the atomic level. Four stable intermediate products during the de-sodiumization process are firstly determined based on the convex hull, and three voltage platforms are then predicted. Except for two voltage platforms (3.37 V and 3.75 V) close to the experimental values, the platform up to 5.28 V exceeds the stability window (4.8 V) of a typical electrolyte, which was not observed experimentally. Excitingly, the change of volume is only 2% during the sodiumization process, which should be the reason for the good cycling stability of this material. Electronic structure analysis also reveals that the valence states of V ions will be changed from V5+ to V4+ during the sodiumization process, resulting in a weak Jahn-Teller distortion in VO5F octahedra, and then making the lattice-constants asymmetrically change. More seriously, combined with a bandgap of 2.0 eV, the conduction band minimum mainly composed of V-t2g non-bonding orbitals has strong localized characteristics, which should be the intrinsic origin of poor electron transport properties for NaxV2(PO4)2FO2. Nonetheless, benefiting from the layer-like structure features with F-segmentation, this material has an ultrafast sodium ionic conductivity comparable to that of NASICON, with an activation energy of only 82 meV. Therefore, our results indicate that maintaining layer-like features and regulating V atoms will be important directions to improve the performance of NaxV2(PO4)2FO2.
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Cypermethrin, one kind of pyrethroid pesticides, has been shown to act as endocrine-disrupting chemicals (EDCs). The purpose of this study was to explore the roles of Sertoli cell apoptosis through mitochondrial pathway associated with calcium (Ca2+) in cypermethrin-induced male reproductive toxicology. The mouse Sertoli cells TM4 were cultured with 0 µM, 10 µM, 20 µM, 40 µM and 80 µM of cypermethrin. We used flow cytometry, Fluo-4 AM, western blot and JC-1 Assay Kit to examine apoptosis, intracellular Ca2+, expressions of mitochondrial apoptotic pathway-related proteins and mitochondrial membrane potential. We found cypermethrin increased apoptosis rate of TM4 cells significantly and with a significant increase in intracellular Ca2+ concentration. Cypermethrin significantly decreased the protein expressions of cytosolic B-cell lymphoma-2 (Bcl-2) and mitochondrial cytochrome c (Cyt-c). The protein expressions of cytosolic Bcl-2-associated x (Bax), Cyt-c, cleaved caspase-3, calmodulin (CaM), Ca2+/CaM-dependent protein kinases II (CaMKII) and phosphorylated CaMKII were increased significantly in cypermethrin-exposed TM4 cells. Cypermethrin decreased mitochondrial membrane potential significantly. Then, Bcl-2 family and Ca2+/CaM/CaMKII pathway participate in cypermethrin-induced homeostasis. Ca2+ overload activates mitochondrial pathway by increasing permeability of mitochondrial membrane and decreasing mitochondrial membrane potential. We suggest cypermethrin induces Sertoli cell apoptosis involving mitochondrial pathway associated with Ca2+ regulated by Bcl-2 family and Ca2+/CaM/CaMKII pathway. The study provides a new insight into mechanisms involved in cypermethrin-induced male reproductive toxicology.
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Due to the low cost, high element abundance and intrinsic safety, potassium-ion batteries (KIBs) have attracted a surge of interest in recent years. Currently, the key challenge and obstacle to the development of KIBs is to find suitable anode materials with large capacity, high rate capability and small lattice changes during the charge/discharge process. MXenes with excellent energy storage properties are promising anode materials for KIBs and their energy performance largely depends on the surface termination. Here, two-dimensional O- and S-terminated V2C MXene anode materials are designed to model high performance potassium-ion batteries. Using first-principles calculations, the structural properties and potential battery performance in KIBs of V2CO2 and V2CS2 are systematically investigated. The inherent metallic nature, a small diffusion barrier, a low average open circuit voltage, and a high theoretical specific capacity (489.93 mA h g-1 of V2CO2 and 200.24 mA h g-1 of V2CS2) demonstrate that both of them are ideal anode materials for KIBs. Meanwhile, we also investigated the mechanism of the difference in energy performance between V2CO2 and V2CS2 at atomic and electronic levels, in other words, the energy performance difference introduced by surface O- and S-terminations.
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BACKGROUND: Non-syndrome cleft lip with or without cleft palate (NSCL/P) is the most common congenital defect with a complex etiology involving both genetic and environmental factors. Our previous research has identified susceptibility genes of NSCL/P using whole-exome sequencing. The study was to determine the effects of small interfering RNA (siRNA)-mediated silencing of genes on cell proliferation and migration to confirm the roles of the genes in NSCL/P. METHODS: We silenced the genes by RNA interference (RNAi) with siRNA in human oral keratinocyte (HOK). We used the Cell Counting Kit-8 (CCK8) assay to determine cell proliferation and the wound healing assay to determine cell migration. RESULTS: Migration of HOK was inhibited by RNAi-induced silencing of adenosine triphosphate binding cassette transporter A4 (ABCA4), erythropoietin produces hepatocyte A receptor 3 (EPHA3), alpha-parvin (PARVA), and platelet-derived growth factor C (PDGFC). The change of proliferation was not found. Treated with siRNA-mediated silencing of type IV collagen (COL4A2), eukaryotic translation initiation factor 2B subunit (EIF2B3), fibroblast growth factor receptor 2 (FGFR2), kinesin family member 20B (KIF20B), ß-lactamase serine-like protein (LACTB), SEC16 homolog A (SEC16A) and thyroid adenoma target gene (THADA) had no effects on cell proliferation and migration of HOK. CONCLUSIONS: We suggest mutations of the four susceptibility genes ABCA4, EPHA3, PARVA and PDGFC are involved in NSCL/P through inhibiting cell migration. The study provides new candidates for future study of NSCL/P.
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Movimiento Celular , Proliferación Celular , Labio Leporino , Fisura del Paladar , ARN Interferente Pequeño , Transportadoras de Casetes de Unión a ATP , Células Cultivadas , Labio Leporino/genética , Fisura del Paladar/genética , Silenciador del Gen , Predisposición Genética a la Enfermedad , Genotipo , Humanos , Cinesinas , Proteínas de la Membrana , Proteínas Mitocondriales , ARN Interferente Pequeño/genética , Proteínas de Transporte Vesicular , beta-LactamasasRESUMEN
The lack of high-performance anode materials has become a major obstacle to the development of Li- and Na-ion batteries. Recently, 2D transition metal borides (e.g. MBenes) have attracted much attention due to their excellent stability and electrical conductivity. Unfortunately, most of the reported MBene phases typically have an intrinsic metal-rich structure with metal atoms exposed on the surface, which harmfully affect the adsorption of Li/Na atoms. Here, through crystal structure prediction combined with the first-principles density functional theory, a novel TiB3 MBene has been determined by altering the proportion of non-metallic element boron to wrap metal atoms and weaken nearest-neighbor electrostatic repulsion. Electrostatic potential analysis visually shows a surface with low potential on the TiB3 monolayer implying high adsorption capacity, and also can be used to quickly screen out the Li/Na adsorption sites. Accurate half-cell battery simulation confirmably shows that the TiB3 monolayer possesses a theoretical specific capacity of 1335.04 and 667.52 mA h g-1 for Li and Na, respectively. The TiB3 monolayer can remain metallic after adsorbing Li/Na atoms, which ensures good conductivity during battery cycling. The ultra-low barrier energy (only 38 meV for Li) and suitable open-circuit voltage indicate excellent charging and discharging capabilities. These results suggest that the TiB3 monolayer could be a promising anode material for Li- and Na-ion batteries, and provide a simple design principle for exposing non-metallic atoms on the surface.
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OBJECTIVE: We aimed to investigate practices of nasogastric tube (NGT) intubation and feeding for adults by clinical nurses in China. METHODS: A self-designed and validated questionnaire comprising 30 questions was distributed to 560 clinical nurses in three comprehensive hospitals of Xiamen, China. The questionnaire covered participants' demographic characteristics, NGT placement, administration of enteral nutrition (EN), and monitoring or management of feeding intolerance. RESULTS: A total 464 (82.9%) questionnaires were completed; 36.2% of nurses used nose-ear-xiphoid and 79.5% forehead-xiphoid measurement to define the internal length of the NGT. Many participants still used traditional methods to confirm NGT placement (auscultation of injected air 50.2%, bubble test 34.7% and observing feeding tube aspirate 34.3%). Bolus feeding was the most commonly used technique to administer EN. A total 97.0% of all nurses used syringes to measure gastric residual volume (GRV), and 62.7% measured GRV every 4-8 hours. The most frequently used GRV threshold values were 200 mL (44.6%) and 150 mL (25.2%). Most nurses stopped feeding immediately when encountering high GRV (84.3%) or diarrhea (45.0%). The nasogastric feeding practices of many clinical nurses were not consistent with international guidelines. CONCLUSIONS: Our study can provide an impetus for nursing administrators to revise their nasogastric feeding procedures, to promote compliance with evidence-based guidelines.
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Nutrición Enteral , Intubación Gastrointestinal , Rol de la Enfermera , Adulto , China/epidemiología , Estudios Transversales , Manejo de la Enfermedad , Nutrición Enteral/métodos , Femenino , Humanos , Intubación Gastrointestinal/métodos , Masculino , Encuestas y CuestionariosRESUMEN
Synthetic pyrethroids are used as insecticides in agriculture and a variety of household applications worldwide. Pyrethroids are widely distributed in all environmental compartments and the general populations are exposed to pyrethroids through various routes. Pyrethroids have been identified as endocrine-disrupting chemicals (EDCs) which are responsible for the male reproductive impairments. The data confirm pyrethroids cause male reproductive damages. The insecticides exert the toxic effects on male reproductive system through various complex mechanisms including antagonizing androgen receptor (AR), inhibiting steroid synthesis, affecting the hypothalamic-pituitary-gonadal (HPG) axis, acting as estrogen receptor (ER) modulators and inducing oxidative stress. The mechanisms of male reproductive toxicity of pyrethroids involve multiple targets and pathways. The review will provide further insight into pyrethroid-induced male reproductive toxicity and mechanisms, which is crucial to preserve male reproductive health.
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Disruptores Endocrinos/efectos adversos , Genitales Masculinos/efectos de los fármacos , Insecticidas/efectos adversos , Piretrinas/efectos adversos , Reproducción/efectos de los fármacos , Salud Reproductiva , Animales , Genitales Masculinos/metabolismo , Genitales Masculinos/patología , Genitales Masculinos/fisiopatología , Humanos , Masculino , Medición de Riesgo , Transducción de SeñalRESUMEN
OBJECTIVE: The purpose of this study was to investigate the anti-androgenic mechanism of cypermethrin involving coactivators. METHODS: Mammalian two-hybrid assays were performed to study the effects of cypermethrin on interactions of the androgen receptor (AR) with the coactivators androgen receptor-associated protein 70 (ARA70) and androgen receptor-associated protein 55 (ARA55). RESULTS: The results showed that AR-ARA70 and AR-ARA55 interactions were remarkably enhanced by dihydrotestosterone (DHT, P ≤ 0.05). Cypermethrin inhibited DHT-induced AR-ARA70 and AR-ARA55 interactions significantly ( P ≤ 0.05). CONCLUSION: The study indicates that cypermethrin exhibits inhibitory effects on AR transcription associated with repression of AR-ARA70 and AR-ARA55 interactions in a ligand-dependent manner. The data show novel anti-androgenic mechanisms of cypermethrin that contribute to male reproductive toxicology.
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Antagonistas de Andrógenos/farmacología , Insecticidas/efectos adversos , Piretrinas/efectos adversos , Receptores Androgénicos/metabolismo , Antagonistas de Receptores Androgénicos/efectos adversos , Animales , Línea Celular , Chlorocebus aethiops , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Proteínas con Dominio LIM/metabolismo , Coactivadores de Receptor Nuclear/metabolismo , Técnicas del Sistema de Dos HíbridosRESUMEN
Oxygen reduction reaction (ORR) is a key microscopic process in many electrochemical applications of materials, where the requirements of their ORR performances may vary strikingly, for example, during the uses of MoS2 as an electrocatalyst and anticorrosion/lubricating coating in aqueous/humid environments, ORR should be activated and inhibited, respectively. To reveal a complete ORR profile of MoS2, using first-principles calculations, we examine the stabilities of various possible zero-dimensional point defects on the surface and one-dimensional edge defects and comprehensively explore the ORR activities on pristine MoS2 surface and those defects in acid/alkaline solutions. It is found that the ORRs on the pristine surface and surfaces with point defects always require large overpotentials (>1.0 V), indicating a defect-immune resistance of the planar MoS2 surface against the ORR. However, the ORR overpotentials on edge defects can reach as low as 0.66 V, corresponding to a relatively high activity close to that of the prototypical catalyst Pt (overpotential â¼0.45 V). Such contrasting ORR behaviors of point and edge defects are also understood in depth by analyzing the underlying thermodynamic and electronic-structure mechanisms. This work not only quantitatively explains the performances of MoS2 in both galvanic corrosion and electrochemical catalysis but also provides a useful structure-ORR map that can facilitate adapting the realistic MoS2 to versatile electrochemical applications.