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Current density imaging is helpful for discovering interesting electronic phenomena and understanding carrier dynamics, and by combining pressure distributions, several pressure-induced novel physics may be comprehended. In this work, noninvasive, high-resolution two-dimensional images of the current density and pressure gradient for graphene ribbon and hBN-graphene-hBN devices are explored using nitrogen-vacancy (NV) centers in diamond under high pressure. The two-dimensional vector current density is reconstructed by the vector magnetic field mapped by the near-surface NV center layer in the diamond. The current density images accurately and clearly reproduce the complicated structure and current flow of graphene under high pressure. Additionally, the spatial distribution of the pressure is simultaneously mapped, rationalizing the nonuniformity of the current density under high pressure. The current method opens a significant new avenue to investigate electronic transport and conductance variations in two-dimensional materials and electrical devices under high pressure as well as for nondestructive evaluation of semiconductor circuits.
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BACKGROUND: Associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) is an innovative surgical approach for the treatment of massive hepatocellular carcinoma (HCC), the key to successful planned stage 2 ALPPS is future liver remnant (FLR) volume growth, but the exact mechanism has not been elucidated. The correlation between regulatory T cells (Tregs) and postoperative FLR regeneration has not been reported. AIM: To investigate the effect of CD4+CD25+ Tregs on FLR regeneration after ALPPS. METHODS: Clinical data and specimens were collected from 37 patients who developed massive HCC treated with ALPPS. Flow cytometry was performed to detect changes in the proportion of CD4+CD25+ Tregs to CD4+ T cells in peripheral blood before and after ALPPS. To analyze the relationship between peripheral blood CD4+CD25+ Treg proportion and clinicopathological information and liver volume. RESULTS: The postoperative CD4+CD25+ Treg proportion in stage 1 ALPPS was negatively correlated with the amount of proliferation volume, proliferation rate, and kinetic growth rate (KGR) of the FLR after stage 1 ALPPS. Patients with low Treg proportion had significantly higher KGR than those with high Treg proportion (P = 0.006); patients with high Treg proportion had more severe postoperative pathological liver fibrosis than those with low Treg proportion (P = 0.043). The area under the receiver operating characteristic curve between the percentage of Tregs and proliferation volume, proliferation rate, and KGR were all greater than 0.70. CONCLUSION: CD4+CD25+ Tregs in the peripheral blood of patients with massive HCC at stage 1 ALPPS were negatively correlated with indicators of FLR regeneration after stage 1 ALPPS and may influence the degree of fibrosis in patients' livers. Treg percentage was highly accurate in predicting the FLR regeneration after stage 1 ALPPS.
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Improving intergenerational mobility is crucial for enhancing the efficacy of human capital, ensuring social vitality, and supporting sustainable long-term economic growth. Based on the China Labor-force Dynamic Survey (CLDS) of 2014, this paper empirically examines the effect of adolescent household migration on intergenerational educational mobility by using a fixed-effect model. The study found that: (1) Household migration in the adolescent period significantly improves intergenerational educational mobility. (2) The quality and quantity of education of offspring are the channels through which household migration improves the intergenerational educational mobility of the household. (3) There are significant differences between urban and rural areas, gender, and household resource allocation in the effect of adolescent household migration on intergenerational educational mobility. As the majority of poor households are unable to improve intergenerational mobility through migration due to its costs and institutional barriers, this paper suggests that the government should concentrate on reducing regional disparities in educational resources, advancing rural education reform, and enhancing social security.
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Desarrollo del Adolescente , Movilidad Social , Adolescente , Humanos , Escolaridad , Composición Familiar , EmpleoRESUMEN
Crystalline organic metal chalcogenides (OMCs) are a class of organic-inorganic hybrid semiconducting materials with continuous M-X (X = S, Se, Te) networks formed by the combination of metal nodes and chalcogen atoms from the organic ligands, which display great potentials in the fields of optoelectronics, catalysis, sensing, as well as energy conversion and storage. Here, we synthesized a wave-like 2D OMC material, [(AgBF4)2Me6BHS]n (Ag-BHSMe), from AgBF4 and 1,2,3,4,5,6-hexa(methylselanyl)benzene (Me6BHS) through a simple homogeneous reaction. In the solid state, Ag-BHSMe exhibits both fluorescence emission at room temperature and phosphorescent emission at 77 K. TEM, SEM, and confocal microscopy revealed that it is an intrinsic blue luminescent microcrystalline material. In addition, we found that it exhibited a highly selective fluorescence enhancement response to Pb2+ in an aqueous solution in the range of 10-4 to 10-2 mol L-1, which demonstrates its potential as a turn-on probe for the detection of lead ions.
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Older adults' family networks and social networks are important factors that influence life satisfaction, but their transmission mechanisms have not been adequately discussed. The objective of this study was to examine the mechanisms through which family networks and social networks influence the life satisfaction of older adults. We empirically examined the effects and mechanisms of older adults' family networks and social networks on their life satisfaction using the 2018 China Longitudinal Aging Social Survey with a sample size of 11,418 older adults aged 60 years and older. In the research sample, 6.47% of older adults were subjected to at least one form of mistreatment. The research results indicate that family networks (ß = 0.0060, p < 0.05) and social networks (ß = 0.0122, p < 0.01) have a significant positive effect on older adults' life satisfaction. The mechanism-of-action test found that family networks and social networks enhance older adults' life satisfaction, mainly by reducing the level of physical mistreatment they experience, but these networks cannot improve the life satisfaction of the elderly by reducing their emotional mistreatment. Further research found that community-provided medical escorts, home chores, and meal delivery services can all alleviate the decline in life satisfaction among older adults due to emotional mistreatment. This study deepens our understanding of how older adults' family and social networks affect their life satisfaction as we examine the mediating role of the physical and emotional mistreatment of older adults and discuss the effects of potential policy interventions.
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The environmental Kuznets curve (EKC) expresses the relationship between environmental quality and economic growth. Based on the defects of previous studies on EKC using only environmental pollution indicators, this study holds that environmental quality is the result of pollutants after treatment, absorption, and self-purification, including two dimensions of pollution and absorption. Therefore, the environmental pollution and absorption data of 74 key environmental monitoring cities in China from 2005 to 2017 were selected, and a comprehensive index of environmental quality was constructed using the vertical and horizontal grading method. Then, based on the relevant economic growth indicators of these cities, they were divided into first-tier and new first-tier, second-tier, third-tier, and below. It was found that the EKC of the total sample, the first-tier and new first-tier cities, and the second-tier cities presented an inverted N-shape and had passed the second inflection point, where environmental quality continues to improve with the deepening of economic growth. There was no EKC in the third-tier and below cities. The findings have important implications. China can cross the second inflection point of the EKC and improve environmental quality at a low income level. Therefore, by vigorously developing cleaner production technologies and raising residents' awareness of environmental protection, it is possible to improve environmental quality at a lower income level than expected, which provides a useful reference for other developing countries.
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Contaminantes Atmosféricos , Desarrollo Económico , Contaminantes Atmosféricos/análisis , Dióxido de Carbono/análisis , China , Ciudades , Contaminación Ambiental/análisisRESUMEN
Exorbitant outputs of waste xylose mother liquor (WXML) and corncob residue from commercial-scale production of xylitol create environmental problems. To reduce the wastes, a Saccharomyces cerevisiae strain tolerant to WXML was conferred with abilities to express the genes of xylose reductase, a xylose-specific transporter and enzymes of the pentose phosphate pathway. This strain showed a high capacity to produce xylitol from xylose in WXML with glucose as a co-substrate. Additionally, a simultaneous saccharification and fermentation (SSF) process was designed to use corncob residues and cellulase instead of directly adding glucose as a co-substrate. Xylitol titer and the productivity were, respectively, 91.0 g l-1 and 1.26 ± 0.01 g l-1 h-1 using 20% WXML, 55 g DCW l-1 delignified corncob residues and 11.8 FPU gcellulose -1 cellulase at 35° during fermentation. This work demonstrates the promising strategy of SSF to exploit waste products to xylitol fermentation process.
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Xilitol , Xilosa , Humanos , Madres , Saccharomyces cerevisiae/genética , Zea maysRESUMEN
The purpose of this paper is to examine the impact of village debt on land transfer. Based on the county-level panel data of village finance and land transfer in 90 counties and 4 economic development zones of Zhejiang Province from 2013 to 2017, this paper carried out multivariate statistical analysis and set a fixed effect model to control the endogenous influence of region and time. It found that village debt as a pressure may encourage village committees to promote rural land transfer, and then especially promote land flows into agricultural firms; as a mechanism, the burden of village organization's transactional debt (historical debt and administrative debt) is the key to promoting the rural land flow to agricultural enterprises; through further analysis, it is found that the village committee seeks "win-win" opportunities by intervening in land circulation to ensure the rights and interests of farmers and to obtain village benefits from them. This paper finds that this kind of push effect has the threshold, the debt will play a significant role in promoting when the debt rate is between 4.65% and 7.9%. In addition, there is regional heterogeneity in the contribution of debt, which exists only in plain, non-coastal and high-dependence areas. The results of this paper verify the view that "community mechanism and market mechanism are embedded and supported each other in acquaintance society" in the theory of community governance. In practice, it provides a realistic basis for policy makers to implement the policy of encouraging farmland circulation and properly deal with the problem of village debt.
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Agricultura/economía , Agricultores , Granjas/economía , HumanosRESUMEN
BACKGROUND: Hepatocellular carcinoma (HCC) patients often developed hepatic arterioportal fistula (APF). The aim of this study is to evaluate the impact of APF on future liver remnant (FLR) regeneration and surgical outcomes after the first stage of associating liver partition and portal vein ligation for staged hepatectomy (stage-I ALPPS). METHODS: Consecutive HCC patients who underwent ALPPS at our center between March 2017 and May 2019 were retrospectively studied. Data for the association between APF and clinicopathological details, liver volume, and surgical outcomes were analyzed. RESULTS: The enrolled 35 HCC patients were divided into three groups: 15 patients with preoperative APF were classified as the APF I group, 10 patients developed APF after stage-I ALPPS as the APF II group, whereas the other 10 patients without APF before and after stage-I ALPPS as the control group. After stage-I ALPPS, patients in the APF I and APF II groups had lower kinetic growth rate (KGR) of FLR volume (6.1±3.2%, 11.4±8.4%, 25.0±8.8% per week, respectively, P<0.001) and took longer median time to reach the sufficient FLR volume for stage-II ALPPS (17.5 days, 12 days, 6 days, respectively, P<0.001) than those in the control group. Meanwhile, the incidence of posthepatectomy liver failure (PHLF) in the APF I and APF II groups was significantly higher than that of the control group (P=0.007). There are 27 (77.1%) patients who completed stage-II ALPPS. The overall survival (OS) rates at 1 and 3 years were 59.3% and 35.1%, whereas the disease-free survival (DFS) rates at 1 and 3 years were 44.4% and 22.9%, respectively. CONCLUSIONS: Hepatic APF is significantly associated with decreased FLR regeneration and a higher risk of PHLF after stage-I ALPPS. HCC patients who are to undergo ALPPS may benefit from the timely perioperative intervention of APF.
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Carcinoma Hepatocelular , Fístula , Neoplasias Hepáticas , Carcinoma Hepatocelular/cirugía , Hepatectomía/efectos adversos , Humanos , Ligadura/efectos adversos , Hígado/cirugía , Neoplasias Hepáticas/cirugía , Regeneración Hepática , Vena Porta/cirugía , Estudios RetrospectivosRESUMEN
Vulnerability assessment has been used in the food fraud mitigation based on the subjective judgement of industry participants and simple calculation. To have a more objective result, an improved vulnerability quantitative assessment method was proposed. The overall fraud vulnerability was described by the vulnerability of fraud factors and the health and economic impact of fraud incidents. The fraud factors were related to opportunity, motivation and control measure. Analytic hierarchy process combined with entropy weighting method (AHP-EWM) and artificial neural networking (ANN) to improve judgment accuracy. In the application in Wuchang rice industrial chain, 51 fraud factors were used in the assessment and 10 experts, 36 farmers, 15 suppliers and 15 supervisors were interviewed. Results showed that Wuchang rice industrial chain was highly vulnerable to fraud. The opportunity for fraud was high, the motivation to commit it was moderate, and controls to prevent it needed reinforcing. Fraud vulnerability differed between farmers and suppliers. To reduce the fraud vulnerability, improved regulations and policies and stiffer penalties were strongly recommended.
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Oryza , China , Entropía , Fraude/prevención & control , Humanos , Redes Neurales de la ComputaciónRESUMEN
OBJECTIVE: To explore the mechanism of action of Bu-Fei-Yi-Shen formula (BFYSF) in treating chronic obstructive pulmonary disease (COPD) based on network pharmacology analysis and molecular docking validation. METHODS: First of all, the pharmacologically active ingredients and corresponding targets in BFYSF were mined by the Traditional Chinese Medicine Systems Pharmacology (TCMSP) database, the analysis platform, and literature review. Subsequently, the COPD-related targets (including the pathogenic targets and known therapeutic targets) were identified through the TTD, CTD, DisGeNet, and GeneCards databases. Thereafter, Cytoscape was employed to construct the candidate component-target network of BFYSF in the treatment of COPD. Moreover, the cytoHubba plug-in was utilized to calculate the topological parameters of nodes in the network; then, the core components and core targets of BFYSF in the treatment of COPD were extracted according to the degree value (greater than or equal to the median degree values for all nodes in the network) to construct the core network. Further, the Autodock vina software was adopted for molecular docking study on the core active ingredients and core targets, so as to verify the above-mentioned network pharmacology analysis results. Finally, the Omicshare database was applied in enrichment analysis of the biological functions of core targets and the involved signaling pathways. RESULTS: In the core component-target network of BFYSF in treating COPD, there were 30 active ingredients and 37 core targets. Enrichment analysis suggested that these 37 core targets were mainly involved in the regulation of biological functions, such as response to biological and chemical stimuli, multiple cellular life processes, immunity, and metabolism. Besides, multiple pathways, including IL-17, Toll-like receptor (TLR), TNF, and HIF-1, played certain roles in the effect of BFYSF on treating COPD. CONCLUSION: BFYSF can treat COPD through the multicomponent, multitarget, and multipathway synergistic network, which provides basic data for intensively exploring the mechanism of action of BFYSF in treating COPD.
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Medicamentos Herbarios Chinos/farmacología , Enfermedad Pulmonar Obstructiva Crónica/tratamiento farmacológico , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Interleucina-17/metabolismo , Medicina Tradicional China , Simulación del Acoplamiento Molecular , Mapas de Interacción de Proteínas , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Transducción de Señal , Programas Informáticos , Receptores Toll-Like/metabolismo , Factor de Necrosis Tumoral alfa/metabolismoRESUMEN
Metal-bis(dithiolene) is one of the most promising structures showing redox activity, excellent electron transport and magnetic properties as well as catalytic activities. Perthiolated coronene (PTC), an emerging highly symmetric ligand containing the smallest graphene nanoplate was employed to manufacture a hybrid material with fused metal-bis(dithiolene) and graphene nanoplate, and it has been demonstrated as an efficient strategy for the construction of multifunctional materials recently. Herein, Co-PTC, a 2D MOF containing Co-bis(dithiolene) and coronene units is prepared via a homogeneous reaction for the first time as powder samples, which are bar-shaped microparticles composed of nanosheets. A neutral formula of [Co3 (C24 S12 )]n is verified for Co-PTC. Co-PTC plays an ultrahigh conductivity of approximately 45â S cm-1 at room temperature as compressed samples, which is among the highest value ever reported for the compressed powder samples of conducting MOFs. Moreover, Co-PTC exhibits good electrocatalytic performance in the hydrogen evolution reaction (HER) with a Tafel slope of 189â mV decade-1 and an operating overpotential of 227â mV at 10â mA cm-1 with pH=0, as well as a remarkable stability in the extremely acidic aqueous solutions, which is the best hydrogen evolution properties among metal-organic compounds.
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In the latest decade, two-dimensional (2D) π-d conjugated metal organic frameworks (MOFs) constructed from metal ions with square-planar coordination geometry and benzene- or triphenylene-derived ligands with ortho-disubstituted N, O, or S donor atoms have received great research interests because of their exceptional physical properties and promising applications. New MOFs of this class are constantly being reported, but 2D metal bis(diselenolene) MOFs based on organic ligands with ortho-disubstituted Se donor atoms have not been synthesized. Herein, a Lewis-acid-induced dealkylation protocol is introduced to the synthesis of arenepolyselenols and related coordination polymers. A triphenylene-derived diselenaborole compound is synthesized and employed as precursor reagent for the synthesis of 2,3,6,7,10,11-triphenylenehexaselenol (H6TPHS) and the first conductive metal organic framework namely Co-TPHS based on triphenylenehexaselenolate (TPHS6-). Co-TPHS exhibits porous honeycomb 2D structure and electrically conductive and glassy magnetic properties.
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OBJECTIVE: To investigate the interaction of non-coding RNAs (ncRNAs) in hepatocellular carcinoma. METHODS: We compared the ncRNAs and mRNAs expression profiles of hepatocellular carcinoma and adjacent tissue by microarray and RT-PCR. The relationship between different ncRNAs and mRNA was analyzed using bioinformatics tools. A regulatory model of ncRNAs in hepatocellular carcinoma cells was developed. RESULTS: A total of 1,704 differentially expressed lncRNAs, 57 miRNAs, and 2,093 mRNAs were identified by microarray analyses. There is a co-expression relationship between two ncRNAs (miRNA-125b-2-3p and lncRNA P26302). Bioinformatics analysis demonstrated cyclin-dependent kinases 1 and CyclinA2 as potential targets of miR-125b-2-3p and Polo-like kinase 1 as potential target of lncRNAP26302. All three gene are important components in the G2/M phase of cell cycle. Subsequently real-time polymerase chain reaction (PCR) studies confirmed these microarray results. CONCLUSION: MiR-125b-2-3p and lncRNAP26302 may affect the G2/M phase of the cell cycle through the regulation of their respective target genes. This study shows a role of ncRNAs in pathogenesis of hepatocellular carcinoma at molecular level, providing a basis for the future investigation aiming at early diagnosis and novel treatment of hepatocellular carcinoma.