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Robust ferroelectricity in nanoscale fluorite oxide-based thin films enables promising applications in silicon-compatible non-volatile memories and logic devices. However, the polar orthorhombic (O) phase of fluorite oxides is a metastable phase that is prone to transforming into the ground-state non-polar monoclinic (M) phase, leading to macroscopic ferroelectric degradation. Here we investigate the reversibility of the O-M phase transition in ZrO2 nanocrystals via in situ visualization of the martensitic transformation at the atomic scale. We reveal that the reversible shear deformation pathway from the O phase to the monoclinic-like (M') state, a compressive-strained M phase, is protected by 90° ferroelectric-ferroelastic switching. Nevertheless, as the M' state gradually accumulates localized strain, a critical tensile strain can pin the ferroelastic domain, resulting in an irreversible M'-M strain relaxation and the loss of ferroelectricity. These findings demonstrate the key role of ferroelastic switching in the reversibility of phase transition and also provide a tensile-strain threshold for stabilizing the metastable ferroelectric phase in fluorite oxide thin films.
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The aggravated mechanical and structural degradation of layered oxide cathode materials upon high-voltage charging invariably causes fast capacity fading, but the underlying degradation mechanisms remain elusive. Here we report a new type of mechanical degradation through the formation of a kink band in a Mg and Ti co-doped LiCoO2 cathode charged to 4.55 V (vs Li/Li+). The local stress accommodated by the kink band can impede crack propagation, improving the structural integrity in a highly delithiated state. Additionally, machine-learning-aided atomic-resolution imaging reveals that the formation of kink bands is often accompanied by the transformation from the O3 to O1 phase, which is energetically favorable as demonstrated by first-principles calculations. Our results provide new insights into the mechanical degradation mechanism of high-voltage LiCoO2 and the coupling between electrochemically triggered mechanical failures and structural transition, which may provide valuable guidance for enhancing the electrochemical performance of high-voltage layered oxide cathode materials for lithium-ion batteries.
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Hypoxia plays an important role in the pathological process of bladder outlet obstruction. Previous research has mostly focused on the dysfunction of bladder smooth muscle cells, which are directly related to bladder contraction. This study delves into the barrier function changes of the urothelial cells under exposure to hypoxia. Results indicated that after a 5-day culture, SV-HUC-1 formed a monolayer and/or bilayer of cell sheets, with tight junction formation, but no asymmetrical unit membrane was observed. qPCR and western blotting revealed the expression of TJ-associated proteins (occludin, claudin1 and ZO-1) was significantly decreased in the hypoxia group in a time-dependent manner. No expression changes were observed in uroplakins. When compared to normoxic groups, immunofluorescent staining revealed a reduction in the expression of TJ-associated proteins in the hypoxia group. Transepithelial electrical resistance (TEER) revealed a statistically significant decrease in resistance in the hypoxia group. Fluorescein isothiocyanate-conjugated dextran assay was inversely proportional to the results of TEER. Taken together, hypoxia down-regulates the expression of TJ-associated proteins and breaks tight junctions, thus impairing the barrier function in human urothelial cells.
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Hipóxia Celular , Proteínas de Junções Íntimas , Junções Íntimas , Urotélio , Humanos , Urotélio/metabolismo , Urotélio/patologia , Junções Íntimas/metabolismo , Proteínas de Junções Íntimas/metabolismo , Proteínas de Junções Íntimas/genética , Linhagem Celular , Proteína da Zônula de Oclusão-1/metabolismo , Proteína da Zônula de Oclusão-1/genética , Ocludina/metabolismo , Ocludina/genética , Claudina-1/metabolismo , Claudina-1/genética , Impedância Elétrica , Regulação da Expressão GênicaRESUMO
BACKGROUND: Quinoa (Chenopodium quinoa Willd.) is valued for its nutritional richness. However, pre-harvest sprouting poses a significant threat to yield and grain quality. This study aims to enhance our understanding of pre-harvest sprouting mitigation strategies, specifically through delayed sowing and avoiding rainy seasons during quinoa maturation. The overarching goal is to identify cold-resistant varieties and unravel the molecular mechanisms behind the low-temperature response of quinoa. We employed bioinformatics and genomics tools for a comprehensive genome-wide analysis of polyamines (PAs) and ethylene synthesis gene families in quinoa under low-temperature stress. RESULTS: This involved the identification of 37 PA biosynthesis and 30 PA catabolism genes, alongside 227 ethylene synthesis. Structural and phylogenetic analyses showcased conserved patterns, and subcellular localization predictions indicated diverse cellular distributions. The results indicate that the PA metabolism of quinoa is closely linked to ethylene synthesis, with multiple genes showing an upregulation in response to cold stress. However, differential expression within gene families suggests a nuanced regulatory network. CONCLUSIONS: Overall, this study contributes valuable insights for the functional characterization of the PA metabolism and ethylene synthesis of quinoa, which emphasize their roles in plant low-temperature tolerance and providing a foundation for future research in this domain.
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Chenopodium quinoa , Chenopodium quinoa/genética , Chenopodium quinoa/metabolismo , Filogenia , Temperatura , Poliaminas/metabolismo , Etilenos/metabolismoRESUMO
Manganese-based oxides (MnOx) suffer from sluggish charge diffusion kinetics and poor cycling stability in sodium ion storage. Herein, an interfacial electric field (IEF) in CeO2/MnOx is constructed to obtain high electronic/ionic conductivity and structural stability of MnOx. The as-designed CeO2/MnOx exhibits a remarkable capacity of 397 F g-1 and favorable cyclic stability with 92.13% capacity retention after 10,000 cycles. Soft X-ray absorption spectroscopy and partial density of states results reveal that the electrons are substantially injected into the Mn t2g orbitals driven by the formed IEF. Correspondingly, the MnO6 units in MnOx are effectively activated, endowing the CeO2/MnOx with fast charge transfer kinetics and high sodium ion storage capacity. Moreover, In situRaman verifies a remarkably increased structural stability of CeO2/MnOx, which is attributed to the enhanced MnâO bond strength and efficiently stabilized MnO6 units. Mechanism studies show that the downshift of Mn 3d-band center dramatically increases the Mn 3d-O 2p orbitals overlap, thus inhibiting the Jahn-Teller (J-T) distortion of MnOx during sodium ion insertion/extraction. This work develops an advanced strategy to achieve both fast and sustainable sodium ion storage in metal oxides-based energy materials.
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BACKGROUND: Mitochondria produce adenosine triphosphate through respiratory activities to power sperm differentiation and motility, and decreased mitochondrial respiratory activity can result in poor sperm motility and asthenospermia. The mitochondrial sheath is a component of the mid-piece of the sperm flagellum, and dysfunction of the sheath can reduce sperm motility and cause male infertility. The membrane occupation and recognition nexus-motif protein 2 (MORN2) is testis enriched in mice, and the MORN motif was reported to play a role in the regulation of bioelectrical signal homeostasis in cardiomyocytes. METHODS: We generated Morn2-/- mice using CRISPR/Cas9 and evaluated the potential functions of MORN2 in spermiogenesis through histological analysis, fertility examination, RT-PCR, CASA, immunofluorescence, TUNEL, electron microscopy analysis, mitochondrial energy metabolism analysis, etc. RESULTS: The Morn2-/- mice were infertile, and their sperm showed severe motility defects. Morn2-/- sperm also had abnormal morphology characterized by bent heads, aberrant mitochondrial sheath formation, lower mitochondrial membrane potential, higher levels of reactive oxygen species, and decreased mitochondrial respiratory activity. CONCLUSIONS: Our study demonstrates that MORN2 is essential for male fertility and indicates that MORN2 functions in mitochondrial sheath formation and regulates mitochondrial respiratory activity.
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Sêmen , Motilidade dos Espermatozoides , Animais , Masculino , Camundongos , Metabolismo Energético , Fertilidade , MitocôndriasRESUMO
Rhizosphere microbiomes are pivotal for crop fitness, but the principles underlying microbial assembly during root-soil interactions across soils with different nutrient statuses remain elusive. We examined the microbiomes in the rhizosphere and bulk soils of maize plants grown under six long-term (≥ 29 yr) fertilization experiments in three soil types across middle temperate to subtropical zones. The assembly of rhizosphere microbial communities was primarily driven by deterministic processes. Plant selection interacted with soil types and fertilization regimes to shape the structure and function of rhizosphere microbiomes. Predictive functional profiling showed that, to adapt to nutrient-deficient conditions, maize recruited more rhizobacteria involved in nutrient availability from bulk soil, although these functions were performed by different species. Metagenomic analyses confirmed that the number of significantly enriched Kyoto Encyclopedia of Genes and Genomes Orthology functional categories in the rhizosphere microbial community was significantly higher without fertilization than with fertilization. Notably, some key genes involved in carbon, nitrogen, and phosphorus cycling and purine metabolism were dominantly enriched in the rhizosphere soil without fertilizer input. In conclusion, our results show that maize selects microbes at the root-soil interface based on microbial functional traits beneficial to its own performance, rather than selecting particular species.
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Alphaproteobacteria , Microbiota , Zea mays/microbiologia , Microbiologia do Solo , Solo/química , Rizosfera , FertilizaçãoRESUMO
Highly regioselective C-H alkylation reactions of tertiary anilines and tertiary alkyl amines with simple alkenes have been achieved by the use of imidazolin-2-iminato scandium alkyl complexes. This protocol provided an efficient and atom-economical route to structurally diverse tertiary amine derivatives. The basic ligand, a coordinating THF in the catalyst and the substitution of alkene substrates were found to switch the regioselectivity of the C-H alkylation reactions of tertiary anilines presumably due to the generation of different types of catalytically active species or the formation of relatively stable intermediates. On the basis of the deuterium labeling experiments and KIE experiments, possible catalytical cycles were provided to understand the reaction mechanism as well as the regioselectivity.
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Waste biomass is one of the promising feedstocks to supply syngas that can be used as fuels, chemicals, reductants, etc. However, the relationship between the component of biomass and the constituent of pyrolysis gas remains unclear. Here, we study the pyrolysis behaviors of various biomasses and reveal the relationship between the biomass components and gas compositions. Further, different pyrolysis gases are applied for the reduction of spent lithium cobalt oxide (LiCoO2) below 500 °C. The pyrolysis gas with a higher concentration of CO has a higher reductivity to convert LiCoO2 to CoO and Li2CO3 with a conversion rate close to 100% in 1 h at 500 °C. The biomass rich in cellulose and with a lower content of lignin tends to produce pyrolysis gas with a high concentration of CO, which comes from the deliberate breakdown of carboxyl, carbonyl, ether, and ester linkages. Moreover, LiCoO2 exerts catalytic functions over the deoxygenation and enhancement of oxygenates and single-ring aromatics. Overall, this paper offers a tailored approach to regulating biomass pyrolysis gases, enabling highly efficient battery recycling and syngas production.
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Fontes de Energia Elétrica , Pirólise , Biomassa , Lignina/química , Reciclagem , GasesRESUMO
BACKGROUND: In China, the effects of heavy metals and metalloids (HMMs) on liver health are not consistently documented, despite their prevalent environmental presence. OBJECTIVE: Our research assessed the association between HMMs and liver function biomarkers in a comprehensive sample of Chinese adults. METHODS: We analyzed data from 9445 participants in the China National Human Biomonitoring survey. Blood and urine were evaluated for HMM concentrations, and liver health was gauged using serum albumin (ALB), alanine aminotransferase (ALT), and aspartate aminotransferase (AST) metrics. Various statistical methods were employed to understand the relationship between 11 HMMs and liver function, adjusting for multiple factors. We also explored interactions with alcohol intake, gender, and age. RESULTS: Among HMMs, selenium in blood [weighted geometric mean (GM) = 95.56 µg/L] and molybdenum in urine (GM = 46.44 µg/L) showed the highest concentrations, while lead in blood (GM = 21.92 µg/L) and arsenic in urine (GM = 19.80 µg/L) had the highest levels among risk HMMs. Manganese and thallium consistently indicated potential risk factor to liver in both sample types, while selenium displayed potential liver protection. Blood HMM mixtures were negatively associated with ALB (ß = -0.614, 95% CI: -0.809, -0.418) and positively with AST (ß = 0.701, 95% CI: 0.290, 1.111). No significant associations were found in urine HMM mixtures. Manganese, tin, nickel, and selenium were notable in blood mixture associations, with selenium and cobalt being significant in urine. The relationship of certain HMMs varied based on alcohol consumption. CONCLUSION: This research highlights the complex relationship between HMM exposure and liver health in Chinese adults, particularly emphasizing metals like manganese, thallium, and selenium. The results suggest a need for public health attention to low dose HMM exposure and underscore the potential benefits of selenium for liver health. Further studies are essential to establish causality.
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Exposição Ambiental , Poluentes Ambientais , Fígado , Metaloides , Metais Pesados , Humanos , China , Masculino , Feminino , Adulto , Estudos Transversais , Pessoa de Meia-Idade , Metais Pesados/urina , Metais Pesados/sangue , Metaloides/urina , Metaloides/sangue , Metaloides/análise , Fígado/efeitos dos fármacos , Exposição Ambiental/análise , Poluentes Ambientais/urina , Poluentes Ambientais/sangue , Adulto Jovem , Idoso , Testes de Função Hepática , População do Leste AsiáticoRESUMO
OBJECTIVE: This study aimed to characterize the computed tomography (CT) enterography features of the small bowel gastrointestinal stromal tumors (GIST) and to determine the association with pathological aggressiveness. METHODS: Computed tomography enterography images of 30 patients with the histologically confirmed small bowel GIST were retrospectively enrolled. Tumor size, location, border, growth pattern, enhancement pattern, necrosis, calcification, ulceration, internal air, nodal metastasis, liver metastasis, peritoneal metastasis, and draining vein were evaluated. Relationships between imaging features and pathological aggressiveness were analyzed using χ2 test or Fisher exact test. Correlations among CT features were analyzed using Spearman correlation analysis. RESULTS: There were significant differences in tumor size between different risk levels (F = 8.388, P < 0.001). There were statistically significant differences in the 5 imaging manifestations of necrosis, ulcer, tumor boundary, drainage vein, and intratumoral gas (P < 0.05). There was a significant negative correlation between tumor size and enhancement type as well as clear tumor boundary. There was a significant positive correlation between tumor size and necrosis, ulcer, drainage vein, intratumoral gas, liver metastasis, and peritoneal metastasis. CONCLUSIONS: Some CT enterography imaging features might be useful in the determination of the pathological aggressiveness in the patients with small bowel GIST.
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BACKGROUND: Parathyroid glands are important endocrine glands, and the identification of normal parathyroid glands is crucial for their protection. The aim of this study is to explore the sonographic characteristics of normal parathyroid glands and analyze the factors affecting their display. METHODS: Seven hundred three subjects who underwent physical examination at our hospital were included. The number, location, size, morphology, echogenicity and blood flow distribution of parathyroid glands were recorded. The ultrasound characteristics and display rate were also summarized. Meanwhile, shear wave elastography was performed in 50 cases to provide the stiffness measurements, and 26 cases received contrast-enhanced ultrasonography for the assessment of microcirculatory perfusion. Furthermore, we analyzed the factors affecting parathyroid display, including basic information of the subjects and ultrasound features of the thyroid. RESULTS: â A total of 1038 parathyroid glands were detected, among which, 79.29% were hyperechoic, 20.71% were isoechoic, 88.15% were oval-shaped, and 86.71% had blood flow of grade 0-I. â¡ 81.79% of the subjects had at least one parathyroid gland detected. ⢠The Emean, Emax, PI and AUC of the parathyroid glands were significantly lower than those of the adjacent thyroid tissue (P < 0.05). ⣠The display of normal parathyroid glands was related to BMI, thyroid echogenicity and thyroid volume of the subjects (P < 0.05). CONCLUSIONS: Normal parathyroid glands tend to appear as oval-shaped hyperechoic nodules with blood flow of grade 0-I. BMI, thyroid echogenicity and thyroid volume are independent factors affecting the display of parathyroid glands.
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Técnicas de Imagem por Elasticidade , Glândulas Paratireoides , Humanos , Glândulas Paratireoides/diagnóstico por imagem , Microcirculação , Ultrassonografia , Glândula Tireoide/diagnóstico por imagemRESUMO
Abiotic stress is a limiting factor in peanut production. Peanut is an important oil crop and cash crop in China. Peanut yield is vulnerable to abiotic stress due to its seeds grown underground. Jasmonic acid (JA) is essential for plant growth and defense against adversity stresses. However, the regulation and mechanism of the jasmonic acid biosynthesis pathway on peanut defense against abiotic stresses are still limitedly understood. In this study, a total of 64 genes encoding key enzymes of JA biosynthesis were identified and classified into lipoxygenases (AhLOXs), alleno oxide synthases (AhAOSs), allene oxide cyclases (AhAOCs), and 12-oxo-phytodienoic acid reductases (AhOPRs) according to gene structure, conserved motif, and phylogenetic feature. A cis-regulatory element analysis indicated that some of the genes contained stress responsive and hormone responsive elements. In addition to proteins involved in JA biosynthesis and signaling, they also interacted with proteins involved in lipid biosynthesis and stress response. Sixteen putative Ah-miRNAs were identified from four families targeting 35 key genes of JA biosynthesis. A tissue expression pattern analysis revealed that AhLOX2 was the highest expressed in leaf tissues, and AhLOX32 was the highest expressed in shoot, root, and nodule tissues. AhLOX16, AhOPR1, and AhOPR3 were up-regulated under drought stress. AhLOX16, AhAOS3, AhOPR1, and AhAOC4 had elevated transcript levels in response to cold stress. AhLOX5, AhLOX16, AhAOC3, AhOPR1, and AhOPR3 were up-regulated for expression under salt stress. Our study could provide a reference for the study of the abiotic stress resistance mechanism in peanut.
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Arachis , Ciclopentanos , Regulação da Expressão Gênica de Plantas , Família Multigênica , Oxilipinas , Proteínas de Plantas , Estresse Fisiológico , Arachis/genética , Arachis/metabolismo , Arachis/crescimento & desenvolvimento , Arachis/fisiologia , Oxilipinas/metabolismo , Ciclopentanos/metabolismo , Estresse Fisiológico/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Filogenia , Estudo de Associação Genômica AmplaRESUMO
Currently, providing patients, particularly those with acute myocardial infarction (AMI), with comprehensive cardiac rehabilitation (CR) has been challenging because of the inadequate availability of medical resources in developing countries. To ensure balance between disease instability and early rehabilitation, strategies for facilitating professional and comprehensive CR opportunities for patients with AMI must be explored.A prospective cohort study was carried out on 1,533 patients with AMI who were admitted to a tertiary hospital between July 2018 and October 2019. Following the principle of voluntarism, 286 patients with AMI participated in home-center-based CR (HCB group), whereas 1,247 patients received usual care (UC group). The primary endpoint of this study was the occurrence of cardiovascular events at 30 months after AMI. Moreover, the study analyzed factors that influence participation rate and effectiveness of the CR model.After analysis, a significant difference in the occurrence of cardiovascular endpoints between the HCB group and the UC group was observed (harzard ratio, 0.68 [95%CI, 0.51-0.91], P = 0.008), with participation in home-center-based CR being an independent influencing factor. Multivariate regression analysis revealed age, gender, smoking history, triglyceride levels, and ejection fraction as independent factors that influence participation rate. Female gender, peak oxygen uptake per kilogram body weight, and ventilation/carbon dioxide production slope were identified as factors that affect the effectiveness of the CR model.In the context of developing countries, this study demonstrates that the home-center-based CR model is efficient and analyzes factors that influence participation rate and effectiveness of the model. These findings provide practical insights for further development of CR programs.
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Reabilitação Cardíaca , Infarto do Miocárdio , Humanos , Masculino , Feminino , Reabilitação Cardíaca/métodos , Infarto do Miocárdio/reabilitação , Pessoa de Meia-Idade , Estudos Prospectivos , Idoso , Resultado do Tratamento , Serviços de Assistência DomiciliarRESUMO
The occurrence and ecological risks of 16 polycyclic aromatic hydrocarbons (PAHs) in different types of urban road runoff in Beijing during two typical rainfall events were studied. The average concentration of PAHs in road runoff particulate was in the order of Guanyuanqiao Road (ring road, 15,175 ng/L) > Huayuanqiao Road (primary road, 4,792 ng/L) > Dongcheng Alley (alley, 4,774 ng/L) > Nansihuan Viaduct (viaduct, 770 ng/L), much higher than dissolved PAHs. The total concentration of ∑16PAHs decreased with runoff scouring. Rainfall conditions and the accumulation of PAHs in the early rainfall period show a significant impact on PAHs pollution. The event mean concentration range of PAHs is 674-21,596 ng/L, following in the order of ring road > primary road > alley > viaduct. The proportion of four-ring PAHs was the highest. The first flush effect of PAHs is found in both rainfall events, and the effect of different ring PAHs is relatively similar. The content of PAHs is positively correlated with the amount of total organic carbon and suspended substance in runoff (r2> 0.72). The ecological risk assessment indicated that PAHs in road runoff except viaduct road corresponded to high risk.
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Poeira , Hidrocarbonetos Policíclicos Aromáticos , Pequim , Poluição Ambiental , Medição de Risco , Monitoramento AmbientalRESUMO
OBJECTIVE: To explore the correlation between clinical classification and genotype and prognosis among Chinese children with Very-long chain acyl-CoA dehydrogenase deficiency (VLCADD). METHODS: A Chinese pedigree affected with VLCADD admitted at the First People's Hospital of Yunnan Province in February 2019 was selected as the study subject. The characteristics of disease onset, diagnosis and treatment and prognosis were retrospectively analyzed. Relevant literature was also systematically searched and reviewed. RESULTS: The proband, a 1-year-old boy, had the clinical manifestations of frequently vomiting, hypoglycemia, abnormal liver function and myocardial enzymes. Tandem mass spectrometry screening showed significantly elevated C14, C14:1, C16:1, C16:2, C18 and C14/C8. Genetic testing revealed that he has harbored compound heterozygous variants of the ACADVL gene, namely c.664G>A (p.G222R) and c.1345G>A (p.E449K), which were respectively derived from his father and mother. The child was diagnosed with VLCADD cardiomyopathy type and deceased 2 weeks later. Literature review has identified 60 Chinese children with VLCADD. The clinical classifications were mainly cardiomyopathy type and liver disease type, which accounted for 73.3% (43/60). The combination of ACADVL gene variants were correlated with the clinical classifications of VLCAD. Children with one or two loss-of-function (LOF) mutations showed more severe clinical manifestation and a higher mortality. Cardiomyopathy type had the poorest prognosis, with a mortality rate of 76.9% (20/26). C14:1 may be used as an indicator for the diagnosis of VLCADD, but cannot be used for clinical subtyping and prognosis evaluation. The c.1349G>A (p.R450H) variant had the highest frequency among the Chinese patients, accounting for 10.8% (13/120). CONCLUSION: The clinical classifications of VLCADD are strongly correlated with the prognosis, and LOF mutations are more common in those with severe clinical manifestations. c.1349G>A (p.R450H) may be the most common variant among the Chinese patients, and early screening and diagnosis can greatly improve the prognosis of patients.
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Cardiomiopatias , Erros Inatos do Metabolismo Lipídico , Doenças Mitocondriais , Doenças Musculares , Criança , Humanos , Lactente , Masculino , Cardiomiopatias/genética , China , Erros Inatos do Metabolismo Lipídico/diagnóstico , Erros Inatos do Metabolismo Lipídico/genética , Doenças Mitocondriais/genética , Doenças Musculares/diagnóstico , Doenças Musculares/genética , Linhagem , Estudos RetrospectivosRESUMO
Random guessing behaviors are frequently observed in low-stakes assessments, often attributed to factors such as test-takers lacking motivation or experiencing time constraints and fatigue. Existing research suggests that responses stemming from random guessing behaviors introduce biases into the constructs and relationships of interest. This is particularly problematic when estimating the relationship between speed and ability. This study introduces a Mixture Fluency model designed to account for random guessing behaviors while utilizing valid response accuracy and response time to uncover students' latent attribute profiles. The model directly addresses a limitation present in the Fluency cognitive diagnostic model (Wang & Chen, Psychometrika, 85, 600-629, (2020), which assumes that test-takers consistently employ solution behaviors when answering questions. To investigate the effectiveness of the proposed Mixture Fluency model, we conducted a simulation study encompassing various simulation conditions. Results from this study not only confirm the model's ability to detect potential random guessing behaviors but also demonstrate its capacity to enhance the inference of targeted latent constructs within the assessment. Additionally, we showcase the practical utility of the proposed model through an application to real data.
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Tempo de Reação , Humanos , Tempo de Reação/fisiologia , Cognição/fisiologia , Modelos Estatísticos , Simulação por Computador , Avaliação Educacional/métodos , Modelos Psicológicos , Psicometria/métodos , Psicometria/instrumentaçãoRESUMO
Transition metal oxides (TMOs) are key in electrochemical energy storage, offering cost-effectiveness and a broad potential window. However, their full potential is limited by poor understanding of their slow reaction kinetics and stability issues. This study diverges from conventional complex nano-structuring, concentrating instead on spin-related charge transfer and orbital interactions to enhance the reaction dynamics and stability of TMOs during energy storage processes. We successfully reconfigured the orbital degeneracy and spin-dependent electronic occupancy by disrupting the symmetry of magnetic cobalt (Co) sites through straightforward strain stimuli. The key to this approach lies in the unfilled Co 3d shell, which serves as a spin-dependent regulator for carrier transfer and orbital interactions within the reaction. We observed that the opening of these 'spin gates' occurs during a transition from a symmetric low-spin state to an asymmetric high-spin state, resulting in enhanced reaction kinetics and maintained structural stability. Specifically, the spin-rearranged Al-Co3O4 exhibited a specific capacitance of 1371â F g-1, which is 38 % higher than that of unaltered Co3O4. These results not only shed light on the spin effects in magnetic TMOs but also establish a new paradigm for designing electrochemical energy storage materials with improved efficiency.
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Transition metal oxides (TMOs) are promising cathode materials for aqueous zinc ion batteries (ZIBs), however, their performance is hindered by a substantial Hubbard gap, which limits electron transfer and battery cyclability. Addressing this, we introduce a heteroatom coordination approach, using triethanolamine to induce axial N coordination on Mn centers in MnO2, yielding N-coordinated MnO2 (TEAMO). This approach leverages the change of electronegativity disparity between Mn and ligands (O and N) to disrupt spin symmetry and augment spin polarization. This enhancement leads to the closure of the Hubbard gap, primarily driven by the intensified occupancy of the Mn eg orbitals. The resultant TEAMO exhibit a significant increase in storage capacity, reaching 351â mAh g-1 at 0.1â A g-1. Our findings suggest a viable strategy for optimizing the electronic structure of TMO cathodes, enhancing the potential of ZIBs in energy storage technology.
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In nucleotide expansion disorders, RNA foci are reportedly associated with neurodegenerative disease pathogeneses. Characteristically, these RNAs exhibit long poly-RNA repeats, such as 47 × CAG, 47 × CUG, or 29 × GGGGCC, usually becoming abnormal pathological aggregations above a critical number of nucleotide repeats. However, it remains unclear whether short, predominantly cellular RNA molecules can cause phase transitions to induce RNA foci. Herein, we demonstrated that short RNAs even with only two repeats can aggregate into a solid-like state via special RNA G-quadruplex structures. In human cells, these solid RNA foci could not dissolve even when using agents that disrupt RNA gelation. The aggregation of shorter RNAs can be clearly observed in vivo. Furthermore, we found that RNA foci induce colocalization of the RNA-binding protein Sam68, a protein commonly found in patients with fragile X-associated tremor/ataxia syndrome, suppressing cell clonogenicity and eventually causing cell death. Our results suggest that short RNA gelation promoted by specific RNA structures contribute to the neurological diseases, which disturb functional cellular processes.