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1.
J Colloid Interface Sci ; 677(Pt A): 820-830, 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-39121666

RESUMEN

Controlling interfacial charge transfer behavior of heterojunction is an arduous issue to efficiently drive separation of photogenerated carriers for improving the photocatalytic activity. Herein, the interface charge transfer behavior is effectively controlled by fabricating an unparalleled VO-NiWO4/PCN heterojunction that is prepared by encapsulating NiWO4 nanoparticles rich in surface oxygen vacancies (VO-NiWO4) in the mesoporous polymeric carbon nitride (PCN) nanosheets. Experimental and theoretical investigations show that, differing with the traditional p-n junction, the direction of built-in electric field between p-type NiWO4 and n-type PCN is reversed interestingly. The strongly codirectional built-in electric field is also produced between the surface defect region and inside of VO-NiWO4 besides in the space charge region, the dual drive effect of which forcefully propels interface charge transfer through triggering Z-Scheme mechanism, thus significantly improving the separation efficiency of photogenerated carriers. Moreover, the unique mesoporous encapsulation structure of VO-NiWO4/PCN heterostructure can not only afford the confinement effect to improve the reaction kinetics and specificity in the CO2 reduction to CO, but also significantly reduce mass transfer resistance of molecular diffusion towards the reaction sites. Therefore, the VO-NiWO4/PCN heterostructure demonstrates the preeminent activity, stability and reusability for photocatalytic CO2 reduction to CO reaction. The average evolution rate of CO over the optimal 10 %-VO-NiWO4/PCN composite reaches around 2.5 and 1.8 times higher than that of individual PCN and VO-NiWO4, respectively. This work contributes a fresh design approach of interface structure in the heterojunction to control charge transfer behaviors and thus improve the photocatalytic performance.

2.
Inorg Chem ; 63(6): 3199-3206, 2024 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-38286822

RESUMEN

A deep insight into surface structural evolution of the catalyst is a challenging issue to reveal the structure-activity relationship. In this contribution, based on a surface alloying strategy, the dual-functional Pd@NiPd catalyst with a unique core-shell hierarchical structure is developed through selective crystal growth, surface cocrystallization, directional self-assembly, and reduction process. The surface defects are created in situ on the outer NiPd alloy layer in the electrochemical redox processes, which endow the Pd@NiPd catalyst with excellent electrocatalytic activity of hydrogen generation reaction (HER) and oxygen generation reaction (OER) in alkaline media. The optimal Pd@NiPd-2 catalyst requires an overpotential of only 18 mV that is far lower than Pt/C benchmark (43 mV) at the current density of 10 mA cm-2 for the HER, and 210 mV that is far lower than RuO2 benchmark (430 mV) at 50 mA cm-2 for the OER. Density functional theory (DFT) calculations reveal that the outstanding electrocatalytic activity is originated from the creation of surface defect structure that induces a significant reduction in the adsorption and dissociation energy barriers of H2O molecules in the HER and a decrease in the conversion energy from O* to OOH* that resulted from the synergy of two adjacent Pd sites by forming O-bridge. This work affords a typical paradigm for exploiting efficient catalysts and investigating the dependence of electrocatalytic activity on the surface structural evolution.

3.
Prev Vet Med ; 220: 106043, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37890218

RESUMEN

Bovine paratuberculosis is a chronic infectious disease caused by Mycobacterium avium subspecies paratuberculosis (MAP). Here, a systematic literature review was conducted to investigate the bovine paratuberculosis distribution and associated risk factors in China before 2022. The databases CNKI, VIP, WanFang, PubMed, and ScienceDirect were used to search for articles. The random effect model of the "Meta" package of "R" software was used, and the Arcsine transformation was chosen for the rate conversion analysis. To reveal the factors that led to research heterogeneity, the research data were used for subgroup analysis and univariate meta-regression analysis. Among the 1238 identified articles, 54 met the eligibility criteria. Based on data obtained from the selected articles, the combined positive rate of bovine paratuberculosis was 6.95% in China. In the sampling year subgroup, the positive rate of bovine paratuberculosis before 2013 was 4.94%, which was lower than in other time periods. In the sampling season subgroup, the highest positive rate of bovine paratuberculosis in cattle was 14.60% in the autumn. Furthermore, in the detection method subgroup, the highest positive rate of bovine paratuberculosis was 7.21%, which was detected by using ELISA. In the age subgroup, the positive rate of bovine paratuberculosis was 17.47% in cattle > 12 months old, significantly higher than other age subgroups. The highest positive rate of bovine paratuberculosis was 11.35% for female cattle in the gender subgroup, while in the geographic region subgroup, the highest positive rate was 8.12% for East China, which was significantly higher than in other regions. The highest positive rate of bovine paratuberculosis was for dairy cattle (8.00%), and the highest positive rate by rearing method was 11.03% for non-scale farming. The effects of different geographical and climatic factors on the positive rate of bovine paratuberculosis were evaluated. In summary, we recommend focusing on screening cattle infected with MAP in warm and humid areas.


Asunto(s)
Enfermedades de los Bovinos , Mycobacterium avium subsp. paratuberculosis , Paratuberculosis , Bovinos , Animales , Femenino , Paratuberculosis/microbiología , Prevalencia , Enfermedades de los Bovinos/microbiología , China/epidemiología
4.
Clin Lab ; 67(10)2021 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-34655193

RESUMEN

BACKGROUND: As a serious public universal health issue, metabolic syndrome (MetS) has a high prevalence world-wide. Some studies illustrated that GCKR modulated insulin action and serum lipids are critical diagnostic criteria of MetS. The goal of this study is to investigate the association between GCKR polymorphisms with metabolic syndrome (MetS) in a Han population from northeast China. METHODS: Four single nucleotide polymorphisms (SNPs, rs1260326, rs8179206, rs780094, and rs2293571) were genotyped in 3,754 participants. MetS was defined according to International Diabetes Federation criteria (2009). Genotype and allele frequency distributions were compared between two groups by chi-squared test. The associations of the four SNPs under different genetic models with MetS were tested by multivariate logistic regression analysis adjusted for age, gender, location, education, occupation alcohol consumption, and smoking. p-values of no more than 0.003125 [0.05/(4 SNPs*4 different genetic models)] after Bonferroni correction were considered statistically significant. Linkage disequilibrium (LD) and haplotype analysis were evaluated by the Haploview software (version 4.2) and SNPStats program. RESULTS: Logistic regression analysis revealed that after Bonferroni correction, rs780094 was associated with MetS under the recessive model (p = 0.002). Weak LD was found for the four SNPs, and the CAGC haplotype appeared to be significantly decreased the risk of MetS (p = 0.026, OR = 0.88, 95% CI = 0.79 - 0.98). CONCLUSIONS: GCKR rs780094 was associated with MetS in northeast Han population, and haplotype CAGC generated by rs1260326, rs8179206, rs780094, and rs2293571 may decrease the risk of the disease.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales , Síndrome Metabólico , Proteínas Adaptadoras Transductoras de Señales/genética , Pueblo Asiatico/genética , Estudios de Casos y Controles , China/epidemiología , Frecuencia de los Genes , Predisposición Genética a la Enfermedad , Haplotipos , Humanos , Síndrome Metabólico/diagnóstico , Síndrome Metabólico/genética , Polimorfismo de Nucleótido Simple
5.
PLoS One ; 16(9): e0257425, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34520494

RESUMEN

BACKGROUND: This novel meta-analysis was conducted to systematically and comprehensively evaluate the prognostic role of the pretreatment PNI in patients with head and neck neoplasms (HNNs) undergoing radiotherapy. METHODS: Three databases, PubMed, Embase, and Web of Science, were used to retrieve desired literature. Hazard ratios (HRs) with 95% confidence intervals (CIs) were extracted and pooled by fixed-effects or random-effects models to analyze the relationship between the PNI and survival outcomes: overall survival (OS), distant metastasis-free survival (DMFS), and progression-free survival (PFS). RESULTS: Ten eligible studies involving 3,458 HNN patients were included in our analysis. The robustness of the pooled results was ensured by heterogeneity tests (I2 = 22.6%, 0.0%, and 0.0% for OS, DMFS, and PFS, respectively). The fixed-effects model revealed a lower pretreatment PNI was significantly related to a worse OS (HR = 1.974; 95% CI: 1.642-2.373; P<0.001), DMFS (HR = 1.959; 95% CI: 1.599-2.401; P<0.001), and PFS (HR = 1.498; 95% CI: 1.219-1.842; P<0.001). The trim-and-fill method (HR = 1.877; 95% CI: 1.361-2.589) was also used to prove that the existing publication bias did not deteriorate the reliability of the relationship. CONCLUSION: The pretreatment PNI is a promising indicator to evaluate and predict the long-term prognostic survival outcomes in HNN patients undergoing radiotherapy.


Asunto(s)
Neoplasias de Cabeza y Cuello/diagnóstico , Neoplasias de Cabeza y Cuello/radioterapia , Carcinoma Nasofaríngeo/diagnóstico , Carcinoma Nasofaríngeo/radioterapia , Evaluación Nutricional , Radioterapia/métodos , Supervivencia sin Enfermedad , Femenino , Neoplasias de Cabeza y Cuello/mortalidad , Humanos , Sistema Inmunológico , Masculino , Carcinoma Nasofaríngeo/mortalidad , Metástasis de la Neoplasia , Pronóstico , Modelos de Riesgos Proporcionales , Reproducibilidad de los Resultados , Resultado del Tratamiento
6.
Artículo en Inglés | MEDLINE | ID: mdl-33429886

RESUMEN

BACKGROUND: At present, most Chinese adults are under great psychological pressure, which seriously affects the improvement of life satisfaction. The purpose of this study was to shed light on the associations between individual social capital and life satisfaction among mainland Chinese adults. METHODS: We used a nationally representative dataset called 2016 China Family Panel Studies, and a total of 26,009 people suited our study requirements. Chi-squared test and binary regression analysis were used to determine the relationship between individual social capital and life satisfaction among mainland Chinese adults. RESULTS: The results indicated that cognitive social capital had significant effects on life satisfaction (p < 0.05), but the impact of structural social capital on life satisfaction became less significant when combined with sociodemographic variables and socioeconomic status (SES) (p > 0.05). Moreover, we also found that life satisfaction was better in married/cohabited (p < 0.05) and in over 65 age group people (p < 0.05). Self-rated income level, self-rated social status, and self-rated health all had positive effects on life satisfaction (p < 0.001). CONCLUSIONS: Given the stabilizing effect of cognitive social capital at the individual level on life satisfaction, the government should attach great importance to this aspect when trying to improve adults' life satisfaction.


Asunto(s)
Capital Social , Adulto , China , Estado de Salud , Humanos , Satisfacción Personal , Clase Social , Apoyo Social , Factores Socioeconómicos
7.
J Affect Disord ; 281: 220-227, 2021 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-33333476

RESUMEN

BACKGROUND: Depression have become a widespread health concern in Chinese society. METHODS: We analyzed the factors influencing the risk of depression among residents aged 16 and over using data from the 2016 China Family Panel Studies (CFPS), in which depression was measured using the Center for Epidemiologic Studies Depression (CES-D20) scale. A total of 26,464 individuals were sampled in a weighted manner to represent the entire country. Univariate and multivariate analysis were used to explore the risk factors for depression and the odds of depression in people with different characteristics. RESULTS: A total of 76.6% of adult residents were mentally healthy. Females had higher rates of depression than males (OR=1.515). There was an "inverted U-shaped" distribution between age and risk of depression. Higher levels of education and better physiological health were associated with a lower risk of depression. Self-evaluated income and social status were not linearly related to the risk of depression but rather had a "U-shaped" distribution. For social capital, better social relationships and a higher level of social trust were associated with a lower risk of depression. Nonsmokers had a lower risk of depression than smokers (OR=0.818). LIMITATIONS: All items were self-reported and some results depend on single item responses. This is a cross-sectional survey so that causative interpretations cannot be drawn. CONCLUSION: These findings suggest potential public health measures whose efficacy needs to be tested and confirmed.


Asunto(s)
Depresión , Composición Familiar , Adolescente , Adulto , China/epidemiología , Estudios Transversales , Depresión/epidemiología , Femenino , Humanos , Masculino , Prevalencia , Factores de Riesgo
8.
Environ Res ; 185: 109471, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32276169

RESUMEN

BACKGROUND: Pregnancy complications, such as gestational diabetes mellitus (GDM) and hypertensive disorders of pregnancy (HDP), have a great impact on public health. Exposure to ambient air pollution during pregnancy may cause pregnancy complications. The aim of our study is to explore the risk of trimester-specific maternal exposure to air pollutants on complications of pregnancy. METHODS: PubMed, EMBASE, Web of Science, and Cochrane were systematically searched for cohort studies published before October 27, 2019 which reported the association between ambient air pollutants (PM2.5, PM10, CO, NO, NO2, NOx, O3, and SO2) and pregnancy complications (GDM, HDP, preeclampsia, and gestational hypertension) during different exposure windows. A meta-analysis was applied to combine relative risks (RRs) and their confidence intervals (CIs) from eligible studies. Quality assessment was conducted and Egger test was used to evaluate the publication bias. All statistical analyses were performed by STATA software (Version 15, StataCorp, College Station, Texas, USA). RESULTS: This meta-analysis consisted of 33 cohort studies conducted on 22,253,277 pregnant women. Meta-analyses showed during the first trimester, there were significant associations of PM10 with gestational hypertension (RR = 1.07, 95% CI: 1.02-1.12 per 10 µg/m3, I2 = 0.0%), of SO2 with GDM (RR = 1.04, 95% CI: 1.00-1.08 per 1 ppb increment, I2 = 54.1%), of PM2.5 with preeclampsia (RR = 0.97, 95% CI: 0.95-1.00 per 5 µg/m3, I2 = 4.1%). During the entire pregnancy, PM2.5 significantly increased the risk of hypertensive disorders of pregnancy (RR = 1.18, 95% CI: 1.02-1.34 per 5 µg/m3, I2 = 85.1%). Egger test indicated that wide-scale publication bias was unlikely. CONCLUSION: Maternal exposure to ambient air pollutants is associated with pregnancy complications especially during the first trimester. Further large multicenter cohort studies considering different constituents of pollutants, levels of disease severity, sensitive populations, and various exposure windows are warranted in the future research.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Complicaciones del Embarazo , Contaminantes Atmosféricos/efectos adversos , Contaminación del Aire/efectos adversos , Contaminación del Aire/análisis , Estudios de Cohortes , Femenino , Humanos , Exposición Materna/efectos adversos , Material Particulado/análisis , Material Particulado/toxicidad , Embarazo , Complicaciones del Embarazo/epidemiología , Texas
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