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As an important disease biomarker, the development of sensitive detection strategies for miRNA, especially intracellular miRNA imaging strategies, is helpful for early diagnosis of diseases, pathological research, and drug development. Hybridization chain reaction (HCR) is widely used for miRNA imaging analysis because of its high specificity and lack of biological enzymes. However, the classic HCR reaction exhibits linear amplification with low efficiency, limiting its use for the rapid analysis of trace miRNA in living cells. To address this problem, we proposed a toehold-mediated exponential HCR (TEHCR) to achieve highly sensitive and efficient imaging of miRNA in living cells using ß-FeOOH nanoparticles as transfection vectors. The detection limit of TEHCR was as low as 92.7 fM, which was 8.8 × 103 times lower compared to traditional HCR, and it can effectively distinguish single-base mismatch with high specificity. The TEHCR can also effectively distinguish the different expression levels of miRNA in cancer cells and normal cells. Furthermore, TEHCR can be used to construct OR logic gates for dual miRNA analysis without the need for additional probes, demonstrating high flexibility. This method is expected to play an important role in clinical miRNA-related disease diagnosis and drug development as well as to promote the development of logic gates.
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MicroRNAs , Hibridização de Ácido Nucleico , MicroRNAs/análise , MicroRNAs/metabolismo , Humanos , Limite de Detecção , Técnicas de Amplificação de Ácido Nucleico/métodos , Compostos Férricos/químicaRESUMO
The identification of a specific tumor cell is crucial for the early diagnosis and treatment of cancer. However, it remains a challenge due to the limited sensitivity and accuracy, long response time, and low contrast of the recent approaches. In this study, we develop a dual miRNA-triggered DNA walker (DMTDW) assisted by APE1 for the specific recognition of tumor cells. miR-10b and miR-155 were selected as the research models. Without miR-10b and miR-155 presence, the DNA walker remains inactive as its walking strand of W is locked by L1 and L2. After miR-10b and miR-155 are input, the DNA walker is triggered as miR-10b and miR-155 bind to L1 and L2 of W-L1-L2, respectively, unlocking W. The DNA walker is driven by endogenous APE1 that is highly catalytic and is highly expressed in the cytoplasm of tumor cells but barely expressed in normal cells, ensuring high contrast and reaction efficiency for specific recognition of tumor cells. Dual miRNA input is required to trigger the DNA walker, making this strategy with a high accuracy. The DMTDW strategy exhibited high sensitivity for miRNA analysis with a detection limit of 44.05 pM. Living cell-imaging experiments confirmed that the DMTDW could effectively respond to the fluctuation of miRNA and specifically identified MDA-MB-231 cells from different cell lines. The proposed DMTDW is sensitive, rapid, and accurate for specific tumor cell recognition. We believe that the DMTDW strategy can become a powerful diagnostic tool for the specific recognition of tumor cells.
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DNA Liase (Sítios Apurínicos ou Apirimidínicos) , MicroRNAs , MicroRNAs/análise , MicroRNAs/metabolismo , MicroRNAs/genética , Humanos , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/metabolismo , DNA/química , Linhagem Celular TumoralRESUMO
Fibrotic hypersensitivity pneumonitis (FHP) is a fatal interstitial pulmonary disease with limited treatment options. Lung macrophages are a heterogeneous cell population that exhibit distinct subsets with divergent functions, playing pivotal roles in the progression of pulmonary fibrosis. However, the specific macrophage subpopulations and underlying mechanisms involved in the disease remain largely unexplored. In this study, a decision tree model showed that matrix metalloproteinase-14 (MMP14) had higher scores for important features in the up-regulated genes in macrophages from mice exposed to the Saccharopolyspora rectivirgula antigen (SR-Ag). Using single-cell RNA sequencing (scRNA-seq) analysis of hypersensitivity pneumonitis (HP) mice profiles, we identified MMP14high macrophage subcluster with a predominant M2 phenotype that exhibited higher activity in promoting fibroblast-to myofibroblast transition (FMT). We demonstrated that suppressing toll-like receptor 2 (TLR2) and nuclear factor kappa-B (NF-κB) could attenuate MMP14 expression and exosome secretion in macrophages stimulation with SR-Ag. The exosomes derived from MMP14-overexpressing macrophages were found to be more effective in regulating the transition of fibroblasts through exosomal MMP14. Importantly, it was observed that the transfer of MMP14-overexpressing macrophages into mice promoted lung inflammation and fibrosis induced by SR-Ag. NSC-405020 binding to the hemopexin domain (PEX) of MMP-14 ameliorated lung inflammation and fibrosis induced by SR-Ag in mice. Thus, MMP14-overexpressing macrophages may be an important mechanism contributing to the exacerbation of allergic reactions. Our results indicated that MMP14 in macrophages has the potential to be a therapeutic target for HP.
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Alveolite Alérgica Extrínseca , Pneumonia , Fibrose Pulmonar , Camundongos , Animais , Fibrose Pulmonar/metabolismo , Metaloproteinase 14 da Matriz/genética , Metaloproteinase 14 da Matriz/metabolismo , Alveolite Alérgica Extrínseca/metabolismo , Alveolite Alérgica Extrínseca/patologia , Macrófagos/metabolismo , Pneumonia/metabolismo , Camundongos Endogâmicos C57BLRESUMO
Fine particulate matter (PM2.5) has been extensively implicated in the pathogenesis of neurodevelopmental disorders, but the underlying mechanism remains unclear. Recent studies have revealed that PM2.5 plays a role in regulating iron metabolism and redox homeostasis in the brain, which is closely associated with ferroptosis. In this study, the role and underlying mechanism of ferroptosis in PM2.5-induced neurotoxicity were investigated in mice, primary hippocampal neurons, and HT22 cells. Our findings demonstrated that exposure to PM2.5 could induce abnormal behaviors, neuroinflammation, and neuronal loss in the hippocampus of mice. These effects may be attributed to ferroptosis induced by PM2.5 exposure in hippocampal neurons. RNA-seq analysis revealed that the upregulation of iron metabolism-related protein Heme Oxygenase 1 (HO-1) and the activation of mitophagy might play key roles in PM2.5-induced ferroptosis in HT22 cells. Subsequent in vitro experiments showed that PM2.5 exposure significantly upregulated HO-1 in primary hippocampal neurons and HT22 cells. Moreover, PM2.5 exposure activated mitophagy in HT22 cells, leading to the loss of mitochondrial membrane potential, alterations in the expression of autophagy-related proteins LC3, P62, and mTOR, as well as an increase in mitophagy-related protein PINK1 and PARKIN. As a heme-degradation enzyme, the upregulation of HO-1 promotes the release of excess iron, genetically inhibiting the upregulation of HO-1 in HT22 cells could prevent both PM2.5-induced mitophagy and ferroptosis. Furthermore, pharmacological inhibition of mitophagy in HT22 cells reduced levels of ferrous ions and lipid peroxides, thereby preventing ferroptosis. Collectively, this study demonstrates that HO-1 mediates PM2.5-induced mitophagy-dependent ferroptosis in hippocampal neurons, and inhibiting mitophagy or ferroptosis may be a key therapeutic target to ameliorate neurotoxicity following PM2.5 exposure.
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Ferroptose , Heme Oxigenase-1 , Hipocampo , Mitofagia , Neurônios , Material Particulado , Regulação para Cima , Animais , Material Particulado/toxicidade , Ferroptose/efeitos dos fármacos , Mitofagia/efeitos dos fármacos , Hipocampo/efeitos dos fármacos , Hipocampo/patologia , Neurônios/efeitos dos fármacos , Neurônios/patologia , Camundongos , Heme Oxigenase-1/metabolismo , Heme Oxigenase-1/genética , Regulação para Cima/efeitos dos fármacos , Masculino , Camundongos Endogâmicos C57BL , Poluentes Atmosféricos/toxicidade , Proteínas de MembranaRESUMO
Rhopalosiphum padi is a global pest that poses a significant threat to wheat crops and has developed resistance to various insecticides. G protein-coupled receptors (GPCRs), known for their crucial role in signaling and biological processes across insect species, have recently gained attention as a potential target for insecticides. GPCR has the potential to contribute to insect resistance through the regulation of P450 gene expression. However, GPCRs in R. padi remained unexplored until this study. We identified a total of 102 GPCRs in R. padi, including 81 receptors from family A, 10 receptors from family B, 8 receptors from family C, and 3 receptors from family D. Among these GPCR genes, 16 were up-regulated in both lambda-cyhalothrin and bifenthrin-resistant strains of R. padi (LC-R and BIF-R). A relaxin receptor gene, RpGPCR41, showed the highest up-regulated expression in both the resistant strains, with a significant increase of 14.3-fold and 22.7-fold compared to the susceptible strain (SS). RNA interference (RNAi) experiments targeting the relaxin receptor significantly increase the mortality of R. padi when exposed to the LC50 concentration of lambda-cyhalothrin and bifenthrin. The expression levels of five P450 genes (RpCYP6CY8, RpCYP6DC1, RpCYP380B1, RpCYP4CH2, and RpCYP4C1) were significantly down-regulated following knockdown of RpGPCR41 in LC-R and BIF-R strains. Our results highlight the involvement of GPCR gene overexpression in the resistance of R. padi to pyrethroids, providing valuable insights into the mechanisms underlying aphid resistance and a potential target for aphid control.
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Afídeos , Resistência a Inseticidas , Inseticidas , Piretrinas , Receptores Acoplados a Proteínas G , Animais , Afídeos/efeitos dos fármacos , Afídeos/genética , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Resistência a Inseticidas/genética , Inseticidas/farmacologia , Inseticidas/toxicidade , Nitrilas/farmacologia , Nitrilas/toxicidade , Piretrinas/farmacologia , Piretrinas/toxicidade , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Interferência de RNARESUMO
BiFeO3 is the only material with ferroelectric Curie temperature and Néel temperature higher than room temperature, making it one of the most well-studied multiferroic materials. Based on an ab initio evolutionary algorithm, we predicted a new cubic C-type antiferromagnetic structure (Fd3Ìm-BiFeO3) at ambient pressure. It was found that Fd3Ìm-BiFeO3 is the hardest BiFeO3 (Vickers hardness â¼ 9.12 GPa), about 78% harder than R3c-BiFeO3 (the well-known multiferroic material), which contributes to extending the life of BiFeO3 devices. In addition, Fd3Ìm-BiFeO3 has the largest shear modulus (83.74 GPa) and the largest Young's modulus (214.72 GPa). Besides, we found an interesting phenomenon that among the common multiferroic materials (BiFeO3, BaTiO3, PbTiO3, SrRuO3, KNbO3, and BiMnO3), Pnma-BiMnO3 has the largest bulk modulus, and its bulk modulus is about 15% larger than that of Fd3Ìm-BiFeO3. However, its Vickers hardness (4.47 GPa) is much smaller than that of Fd3Ìm-BiFeO3. This is because the Vickers hardness is proportional to the shear modulus and the shear modulus of Fd3Ìm-BiFeO3 is larger than that of Pnma-BiMnO3. This work provides a deeper and more comprehensive understanding of BiFeO3.
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OBJECTIVE: To evaluate the association between plasma transfusion and bleeding complications in critically ill patients with an elevated international normalized ratios undergoing invasive procedures. METHODS: A retrospective study was conducted to evaluate a consecutive sample of critically ill adult patients undergoing invasive procedures (N = 487) with an international normalized ratio ≥ 1.5 between January 1, 2019 and December 31, 2019. Among the followed patients, 125 were excluded due to incomplete case records and 362 were finally included in this investigation. The exposure was whether plasma had been transfused within 24 h before the invasive procedure. The primary outcome was the occurrence of postprocedural bleeding complications. Secondary outcomes included transfusion of red blood cells within 24 h of the invasive procedure, and additional patient-important outcomes such as mortality and length of stay. Tests were performed with univariate and propensity-matched analyses. RESULTS: Of the 362 study participants, 99 (27.3 %) received a preprocedural plasma transfusion. In the propensity score-matched analysis, the rate of the occurrence of postprocedural bleeding complications between two groups was not statistically different (OR, 0.605[95 % CI, 0.341-1.071]; P = .085). The rate of postoperative red blood cell transfusion in the plasma transfusion group was higher than that in the non-plasma transfusion group (35.5 % vs 21.5 %; P < .05). No statistically significant difference in mortality was observed between the two groups (29.0 % vs 31.6 %; P = .101). CONCLUSIONS: Prophylactic plasma transfusion failed to reduce postprocedural bleeding complications in ill critically patients with a coagulopathy. Meanwhile, it was associated with increased red blood cell transfusion after invasive procedures. Findings suggest that abnormal preprocedural international normalized ratios should be managed more conservatively.
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Transfusão de Sangue , Estado Terminal , Adulto , Humanos , Estudos de Coortes , Estudos Retrospectivos , Estado Terminal/terapia , Coeficiente Internacional NormatizadoRESUMO
Solar cell is a kind of devices for renewable and environmentally friendly energy conversion. One of the important things for solar cells is conversion efficiency. While much attention has been drawn to improving efficiency, the role of strain engineering in two-dimensional materials is not yet well-understood. Here, we propose aPmc21-As monolayer that can be used as a solar cell absorbing material. The bandgap of single-layerPmc21-As can be tuned from 1.83 to 0 eV by applying tensile strain, while keeping the direct bandgap characteristic. Moreover, it has high light absorption efficiency in the visible and near-infrared regions, which demonstrates a great advantage for improving the conversion efficiency of solar cells. Based on the tunable electronic and optical properties, a novel design strategy for solar cells with a wide absorption range and high absorption efficiency is suggested. Our results not only have direct implication in strain effect on two-dimensional materials, but also give a possible concept for improving the solar cell performance.
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BiFeO3 is one of the most widely studied multiferroic materials, because of its large spontaneous polarization at room temperature, as well as ferroelasticity and antiferromagnetism. Using an ab initio evolutionary algorithm, we found two new dynamically stable BiFeO3 structures (P63 and P6322) at ambient pressure. Their energy is only 0.0662 and 0.0659 eV per atom higher than the famous R3c-BiFeO3, and they have large spontaneous polarization, i.e., 71.82 µC cm-2 and 86.06 µC cm-2, respectively. The spontaneous polarization is caused by the movement of the Bi3+ atom along the [001] direction and mainly comes from the 6s electron of Bi3+. Interestingly, there is no lone pair electron of Bi3+, which is different from R3c-BiFeO3. The new structures have the same magnetic configurations as R3c-BiFeO3 (G-type antiferromagnetism), but they are characterized by one-dimensional channels linked by a group of two via surface-sharing oxygen octahedra. Due to the similarity of the two structures, both of them have indirect bandgap structures, and the bandgaps are 2.62 eV and 2.60 eV, respectively. This work not only broadens the structural diversity of BiFeO3 but also has constructive significance for the study of spontaneous polarization of new structures of multiferroic materials.
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BACKGROUND: At the global level, dementia is the leading cause of dependence and disability among the elderly. Although the preponderant prevalence in women has been identified, the sex differences in risk factors were unclear. We aimed to evaluate the sex differences in the prevalence of nonvascular cognitive impairment and the risk factors among the elderly in rural China screened with the Mini-Mental State Examination (MMSE). METHODS: Between 2014 and 2015, a population-based cross-section study was conducted to collect basic information among the elderly aged 60 years and over. Those participants with the previous history of stroke or heart disease were excluded in this study. Nonvascular cognitive impairment was assessed using the MMSE scores. RESULTS: The prevalence of cognitive impairment was 32.4% overall, 25.6% in men and 38.1% in women. In the multivariate analysis, older age and lower education were risk factors both in men and in women; older, large waist circumference was a protective factor for cognitive function in men; higher blood pressure was the risk factor in women. CONCLUSION: These findings suggest that it is crucial to manage and control hypertension and improve educational attainment in order to reduce the prevalence and burden of nonvascular cognitive impairment among low-income residents, both men and women, in rural China.
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Cognição , Disfunção Cognitiva/epidemiologia , Caracteres Sexuais , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , China , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pobreza , Prevalência , Fatores de Risco , População Rural , Fatores SexuaisRESUMO
BACKGROUND AND PURPOSE: Although stroke in the young and middle aged accounts for 31% of all strokes in China, the disease burden is unknown. We aimed to determine the secular trends in stroke incidence and the transition of subtypes in rural China over a 24-year period. METHODS: In 1992, 14 920 residents were recruited to participate in the Tianjin Brain Study. Stroke events and all deaths were registered annually. We assessed the trends in incidence of first-ever stroke, including intracerebral hemorrhage and ischemic stroke, among adults aged 35 to 64 years during 1992 to 1999, 2000 to 2007, and 2008 to 2015. The annual proportion of change in stroke incidence was evaluated from 1992 to 2015. RESULTS: The age-standardized incidence of first-ever stroke per 100 000 person-years increased significantly, from 122 in 1992 to 1999, to 215.8 in 2000 to 2007, to 471.8 in 2008 to 2015. The incidence of first-ever stroke increased annually by 11.9% overall (12.4% in men, 9.0% in women, 8.7% for intracerebral hemorrhage, and 10.7% for ischemic stroke; P<0.001). The greatest increases were observed in adults aged 55 to 64 years, with an annual increase of 11.6% for ischemic stroke (10.8% in men and 6.9% in women). However, the proportion of intracerebral hemorrhage has not changed over the past 24 years. CONCLUSIONS: In contrast with that in developed countries, the burden of stroke in China originates primarily from young and middle-aged adults. Thus, control of risk factors in this population is required to reduce the future burden of stroke in China.
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Efeitos Psicossociais da Doença , Pobreza/economia , Pobreza/tendências , População Rural/tendências , Acidente Vascular Cerebral/economia , Acidente Vascular Cerebral/epidemiologia , Adulto , China/epidemiologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
BACKGROUND AND PURPOSE: We investigated secular trends in the age of stroke onset and stroke incidence in a low-income population in rural China. METHODS: The study population was recruited from a population-based stroke surveillance study conducted in a township in Tianjin, China, from 1992 to 2014. The trends in mean age and incidence of first-ever stroke were assessed by sex and stroke subtype. Risk factor surveys were conducted in the same population in both 1991 and 2011. RESULTS: A total of 1053 patients experienced first-ever stroke from 1992 to 2014. The mean age of stroke onset in men significantly decreased by 0.28 years annually overall, by 0.56 years for intracerebral hemorrhage, and by 0.22 years for ischemic stroke (P<0.05). However, a similar trend was not observed in women. The age-standardized first-ever stroke incidence in the same population significantly increased across sex and stroke subtypes, increased by 6.3% overall, 5.5% for men, 7.9% for women, 4.6% for intracerebral hemorrhage, and 7.3% for ischemic stroke (P<0.05) during 1992 to 2014. Concurrently, the prevalence of hypertension, diabetes mellitus, obesity, current smoking, and alcohol consumption increased significantly in young and middle-aged adults from 1991 to 2011. CONCLUSIONS: The age of stroke onset tends to be younger among low-income population in China after the dramatic increased incidence of stroke during the gradual extension of life expectancy of population in China. These findings suggested that stroke burden will continue to increase in the long time, unless the risk factors in low-income populations are effectively controlled.
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Isquemia Encefálica/epidemiologia , Expectativa de Vida , Pobreza , Acidente Vascular Cerebral/epidemiologia , Fatores Etários , Idade de Início , Idoso , Idoso de 80 Anos ou mais , China/epidemiologia , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Fatores SexuaisRESUMO
Background: Lower respiratory tract infections represent prevalent ailments. Nonetheless, current comprehension of the microbial ecosystems within the lower respiratory tract remains incomplete and necessitates further comprehensive assessment. Leveraging the advancements in metagenomic next-generation sequencing (mNGS) technology alongside the emergence of machine learning, it is now viable to compare the attributes of lower respiratory tract microbial communities among patients across diverse age groups, diseases, and infection types. Method: We collected bronchoalveolar lavage fluid samples from 138 patients diagnosed with lower respiratory tract infections and conducted mNGS to characterize the lung microbiota. Employing various machine learning algorithms, we investigated the correlation of key bacteria in patients with concurrent bronchiectasis and developed a predictive model for hospitalization duration based on these identified key bacteria. Result: We observed variations in microbial communities across different age groups, diseases, and infection types. In the elderly group, Pseudomonas aeruginosa exhibited the highest relative abundance, followed by Corynebacterium striatum and Acinetobacter baumannii. Methylobacterium and Prevotella emerged as the dominant genera at the genus level in the younger group, while Mycobacterium tuberculosis and Haemophilus influenzae were prevalent species. Within the bronchiectasis group, dominant bacteria included Pseudomonas aeruginosa, Haemophilus influenzae, and Klebsiella pneumoniae. Significant differences in the presence of Pseudomonas phage JBD93 were noted between the bronchiectasis group and the control group. In the group with concomitant fungal infections, the most abundant genera were Acinetobacter and Pseudomonas, with Acinetobacter baumannii and Pseudomonas aeruginosa as the predominant species. Notable differences were observed in the presence of Human gammaherpesvirus 4, Human betaherpesvirus 5, Candida albicans, Aspergillus oryzae, and Aspergillus fumigatus between the group with concomitant fungal infections and the bacterial group. Machine learning algorithms were utilized to select bacteria and clinical indicators associated with hospitalization duration, confirming the excellent performance of bacteria in predicting hospitalization time. Conclusion: Our study provided a comprehensive description of the microbial characteristics among patients with lower respiratory tract infections, offering insights from various perspectives. Additionally, we investigated the advanced predictive capability of microbial community features in determining the hospitalization duration of these patients.
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Bactérias , Líquido da Lavagem Broncoalveolar , Sequenciamento de Nucleotídeos em Larga Escala , Aprendizado de Máquina , Metagenômica , Microbiota , Infecções Respiratórias , Humanos , Metagenômica/métodos , Pessoa de Meia-Idade , Infecções Respiratórias/microbiologia , Infecções Respiratórias/virologia , Idoso , Masculino , Feminino , Adulto , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Líquido da Lavagem Broncoalveolar/microbiologia , Microbiota/genética , Adulto Jovem , Bronquiectasia/microbiologia , Idoso de 80 Anos ou mais , Metagenoma , Adolescente , Pulmão/microbiologia , Pulmão/virologia , HospitalizaçãoRESUMO
A fibrous strong base anion exchanger (QAPPS) was prepared for the first time via chloromethylation and quaternary amination reaction of polyphenylene sulfide fiber (PPS), and its physical-chemical structure and adsorption behavior for Cr(VI) were characterized by FTIR, Energy Dispersive Spectrometry, TG-DTG, elemental analysis and batch adsorptive technique, respectively. The novel fibrous adsorbent could effectively adsorb Cr(VI) over the pH range 1-12, the maximum adsorption capacity was 166.39 mg/g at pH 3.5, and the adsorption behavior could be described well by Langmuir isotherm equation model. The adsorption kinetics was studied using pseudo first-order and pseudo second-order models, and the t1/2 and equilibrium adsorption time were 5 and 20 min respectively when initial Cr(VI) concentration was 100 mg/L. The saturated fibers could be regenerated rapidly by a mixed solution of 0.5 mol/L NaOH and 0.5 mol/L NaCl, and the adsorption capacity was well maintained after six adsorption-desorption cycles.
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Resinas de Troca Aniônica/síntese química , Cromo/química , Polímeros/química , Poluentes Químicos da Água/química , Adsorção , Concentração de Íons de Hidrogênio , Cinética , TermodinâmicaRESUMO
In metal-N-C systems, doped metals have an obvious valence change in the process of Li-ion deintercalation, which is in agreement with the operational principle of traditional anode materials. Doped metals will transfer some electrons to the neighboring N atoms to improve the valence state. Along with Li adsorption, the charge transferred to the nearest N or C from Li is less compared to that transferred to the doped metal. Hence, doped metals have an obvious valence change in the process of Li-ion deintercalation, and doped N just serves as a container for holding electrons. The local states of C and N p electrons in the Co-N-C structure can be fully destroyed, which can effectively improve the electronic properties of graphene.
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Diazinon is one of the most widely used organophosphate insecticides, one that is frequently detected in the environment. In this study, a diazinon-degrading bacterium, DI-6, previously isolated from diazinon-contaminated soil in China has been subsequently identified as Sphingobium sp. on the basis of its physiological and biochemical characteristics, as well as by virtue of a comparative analysis of 16S rRNA gene sequences. This strain is capable of using diazinon as its sole carbon source for growth and was able to degrade 91.8% of 100 mg L-1 diazinon over a 60-h interval. During the degradation of diazinon, the following seven metabolites were captured and identified by gas chromatography/mass spectrometry (GC-MS) analysis: diazoxon, diazinon aldehyde, isopropenyl derivative of diazinon, hydroxyethyl derivative of diazinon, diazinon methyl ketone, O-[2-(1-hydroxyethyl)-6-methylpyrimidin-4-yl] O-methyl O-hydrogen phosphorothioate, and O-(6-methyl pyrimidin-4-yl) O,O-dihydrogen phosphorothioate. Based on these metabolites, a novel microbial biodegradation pathway of diazinon by Sphingobium sp. DI-6 is proposed. This research provides potentially useful information for the application of the DI-6 strain in bioremediation of diazinon-contaminated environments.
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Zero (or near-zero) Poisson's ratio (ZPR) materials have important applications in the field of precision instruments because one of their faces is stable and will not be affected by strain. However, ZPR materials are extremely rare. Here, we report a novel ZPR material, two-dimensional P2/m arsenene, by first principles calculations. Its Poisson's ratio is -0.00021 (strain along zigzag direction), which is smaller than all the known near-zero Poisson's ratio crystal materials, and even 10 times smaller than Me-graphene (0.002). This feature makes it have huge potential applications in the field of precision instruments such as aviation, medicine, and flexible electronic devices. Besides, the band-gap range of P2/m arsenene is 1.420-2.154 eV (the corresponding wavelength is 873-575 nm) under strain from -5% to 5% along the zigzag direction, which is suitable for infrared and visible optoelectronic devices.
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Background: A number of studies have documented that coronavirus disease 2019 (COVID-19) brought more negative impact on the physical and psychological functioning of frontline healthcare workers. Especially, sleep quality was focused. This study aimed to investigate the sleep quality of frontline healthcare workers, risk factors for sleep quality, and the effect of Tai Chi training. Methods: A total of 98 frontline healthcare workers were recruited, coming from the infection department, fever clinic, laboratory, and medical imaging department in a COVID-19-designated hospital in Shanghai. Of them, 50 participated in a 2-week intervention and were randomized to receive a Tai Chi training or relaxation training. Participants were assessed at baseline, 7 and 14 days after participation. Demographic information, sleep quality, and anxiety were measured by using the demographic questionnaire, Pittsburgh Sleep Quality Index (PSQI) and Beck Anxiety Inventory (BAI). Results: 13.3% participants were above the cut-off score (>10) for the PSQI. Regression analysis showed gender, age, working years, and job category had effect on sleep quality. Compared to the control group, participants in the Tai Chi training group had lower scores on both PSQI (p < 0.05) and BAI (p < 0.01) after the 2-week intervention. Conclusion: It was demonstrated that poor sleep quality existed in the frontline healthcare workers, which was related to gender, age, working years, and job category. Tai Chi training can dramatically improve their sleep quality and reduce anxiety symptoms.
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Recurrent stroke is becoming an increasingly important public health issue owing to the increased risk of disability and death. However, population-based studies investigating the rate of recurrent stroke in China are rare. We explored the rate and determinants of recurrent stroke within 1 and 5 years after the initial stroke in a rural population in China. Data for stroke events were obtained from the Tianjin Brain Study, conducted between 1992 and 2016. The age-standardized rates of recurrent stroke within the first year and the first 5 years after the initial stroke were calculated for this period. Determinants of recurrent stroke were assessed using Cox regression analyses. The overall age-standardized rate of recurrent stroke within 1 year was 5.7% (men, 6.9%; women, 4.6%); within 5 years, the overall recurrent stroke rate was 22.5% (men, 24.0%; women, 20.2%). The recurrence rate increased with advancing age and decreased with increased educational attainment. Age ≥65 years and a history of alcohol consumption were independent risk factors for recurrent stroke within 1 year after the incident stroke, after adjusting for age, sex, education, hypertension, diabetes, smoking, and alcohol consumption. However, the risk of recurrent stroke within 5 years after the incident stroke was positively associated with male sex, age ≥65 years, a lower level of education, known diabetes, and alcohol consumption, after adjusting for the previously indicated covariates. These findings suggest a crucial need to address risk factor management among stroke patients to reduce the burden of stroke, especially among low-income populations. Furthermore, a multicenter, large sample, nationwide study is urgently needed.
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We aimed to explore the impact of blood pressure (BP) levels on atherosclerosis in a rural Chinese population with a low-education level, low income, high incidence of stroke, and high prevalence of hypertension. B-mode ultrasonography was used to measure carotid intima-media thickness (CIMT) in adults aged ≥ 45 years with no history of stroke or cardiovascular disease. A total of 5403 eligible subjects were included in this study. The mean CIMT was 0.57 mm overall, 0.58 mm for men and 0.56 mm for women. Systolic blood pressure (SBP) and hypertension were significantly associated with increased CIMT. CIMT increased by 0.42 µm for every 1 mm Hg-increase in SBP (P < 0.001). The mean CIMT in participants with a history of hypertension was 17.42 µm greater than that in participants with no history of hypertension (P < 0.001). Diastolic blood pressure (DBP) was a protective factor, as CIMT decreased by 0.44 µm with every 1 mm Hg-increase in DBP (P = 0.011).