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1.
Chemistry ; : e202402023, 2024 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-39032086

RESUMEN

This study presents the design, synthesis, and comprehensive characterization of a novel series of D-π-A type malononitrile-derived chromophores, BTC-1 to BTC-4. Combining various spectroscopic techniques, nonlinear Z-scan measurements, and quantum chemical calculations, we revealed the intricate relationship between nonlinear optical properties and the interplay of molecular structure, intramolecular charge transfer (ICT), and dipole moments (µ). Our experimental and computational findings corroborate that the polarization degree in the ground state, the charge separation in the excited state and ICT collectively dictate the nonlinear optical properties of the compounds. Notably, BTC-1 exhibits an exceptional nonlinear absorption coefficient ß value (2 × 10-8 m W-1), attributed to its optimized charge transfer efficiency and pronounced degree of charge separation. Our findings provide actionable insights for the rational design of high-performance organic NLO materials with potential applications in advanced photonic devices.

2.
BMC Public Health ; 24(1): 209, 2024 01 17.
Artículo en Inglés | MEDLINE | ID: mdl-38233763

RESUMEN

BACKGROUND: In many areas of China, over 30% of tuberculosis cases occur among the elderly. We aimed to investigate the spatial distribution and environmental factors that predicted the occurence of tuberculosis in this group. METHODS: Data were collected on notified pulmonary tuberculosis (PTB) cases aged ≥ 65 years in Zhejiang Province from 2010 to 2021. We performed spatial autocorrelation and spatial-temporal scan statistics to determine the clusters of epidemics. Spatial Durbin Model (SDM) analysis was used to identify significant environmental factors and their spatial spillover effects. RESULTS: 77,405 cases of PTB among the elderly were notified, showing a decreasing trend in the notification rate. Spatial-temporal analysis showed clustering of epidemics in the western area of Zhejiang Province. The results of the SDM indicated that a one-unit increase in PM2.5 led to a 0.396% increase in the local notification rate. The annual mean temperature and precipitation had direct effects and spatial spillover effects on the rate, while complexity of the shape of the greenspace (SHAPE_AM) and SO2 had negative spatial spillover effects. CONCLUSION: Targeted interventions among the elderly in Western Zhejiang may be more efficient than broad, province-wide interventions. Low annual mean temperature and high annual mean precipitation in local and neighboring areas tend to have higher PTB onset among the elderly.


Asunto(s)
Tuberculosis Pulmonar , Tuberculosis , Anciano , Humanos , Tuberculosis/epidemiología , Tuberculosis Pulmonar/epidemiología , China/epidemiología , Análisis Espacio-Temporal , Análisis Espacial , Incidencia
3.
Angew Chem Int Ed Engl ; : e202405839, 2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38801294

RESUMEN

Triggering the lattice oxygen oxidation mechanism is crucial for improving oxygen evolution reaction (OER) performance, because it could bypass the scaling relation limitation associated with the conventional adsorbate evolution mechanism through the direct formation of oxygen-oxygen bond. High-valence transition metal sites are favorable for activating the lattice oxygen, but the deep oxidation of pre-catalysts suffers from a high thermodynamic barrier. Here, taking advantage of the Jahn-Teller (J-T) distortion induced structural instability, we incorporate high-spin Mn3+ ( t 2 g 3 e g 1 ${{t}_{2g}^{3}{e}_{g}^{1}}$ ) dopant into Co4N. Mn dopants enable a surface structural transformation from Co4N to CoOOH, and finally to CoO2, as observed by various in situ spectroscopic investigations. Furthermore, the reconstructed surface on Mn-doped Co4N triggers the lattice oxygen activation, as evidenced experimentally by pH-dependent OER, tetramethylammonium cation adsorption and online electrochemical mass spectrometry measurements of 18O-labelled catalysts. In general, this work not only offers the introducing J-T effect approach to regulate the structural transition, but also provides an understanding about the influence of the catalyst's electronic configuration on determining the reaction route, which may inspire the design of more efficient catalysts with activated lattice oxygen.

4.
Clin Infect Dis ; 77(10): 1468-1475, 2023 11 17.
Artículo en Inglés | MEDLINE | ID: mdl-37506258

RESUMEN

BACKGROUND: Mass tuberculosis (TB) screening has been recommended in certain high-risk populations. However, population-based screening interventions have rarely been implemented. Whether mass screening improves health equity is unknown. METHODS: We implemented a mass TB screening intervention among elderly persons (>60 years old) in Lanxi County, China. Standardized questionnaires, physical examinations, and chest radiographs (CXRs) were administered to all participants. Systematic testing with computed tomography, smear, culture, or Xpert was performed among persons with an abnormal CXR. We assessed TB prevalence per 100 000 persons and constructed multivariable regression models among subgroups that were and were not screened. Medical insurance was categorized as participation in either a basic program with limited coverage or a more comprehensive coverage program. RESULTS: In total, 49 339 individuals (32% of the elderly population in Lanxi) participated in the screening. One hundred fifteen screened persons were diagnosed with TB (233 cases per 100 000 persons), significantly higher than persons not screened (168 cases among 103 979 person-years; prevalence-to-case notification ratio, 1.44 [95% confidence interval {CI}, 1.14-1.83]). This increase was largely driven by diagnosis of asymptomatic disease during mass screening (n = 57 [50% of participants with TB]). Participants with basic medical insurance were much more likely to be diagnosed through mass screening than by passive detection (adjusted odds ratio, 4.52 [95% CI, 1.35-21.28]). CONCLUSIONS: In a population-based, mass TB screening intervention encompassing >30% of the elderly population in a county in rural China, case finding was 44% higher than background detection, driven by diagnosis of TB without recognized symptoms. Importantly, mass screening identified TB in people with limited healthcare options who were less likely to be found through background case detection.


Asunto(s)
Tuberculosis , Humanos , Anciano , Persona de Mediana Edad , Tuberculosis/diagnóstico , Tuberculosis/epidemiología , Tamizaje Masivo/métodos , Factores de Riesgo , China/epidemiología , Prevalencia
5.
J Am Chem Soc ; 144(31): 14005-14011, 2022 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-35904545

RESUMEN

The carbon-carbon (C-C) bond formation is essential for the electroconversion of CO2 into high-energy-density C2+ products, and the precise coupling pathways remain controversial. Although recent computational investigations have proposed that the OC-COH coupling pathway is more favorable in specific reaction conditions than the well-known CO dimerization pathway, the experimental evidence is still lacking, partly due to the separated catalyst design and mechanistic/spectroscopic exploration. Here, we employ density functional theory calculations to show that on low-coordinated copper sites, the *CO bindings are strengthened, and the adsorbed *CO coupling with their hydrogenation species, *COH, receives precedence over CO dimerization. Experimentally, we construct a fragmented Cu catalyst with abundant low-coordinated sites, exhibiting a 77.8% Faradaic efficiency for C2+ products at 300 mA cm-2. With a suite of in situ spectroscopic studies, we capture an *OCCOH intermediate on the fragmented Cu surfaces, providing direct evidence to support the OC-COH coupling pathway. The mechanistic insights of this research elucidate how to design materials in favor of OC-COH coupling toward efficient C2+ production from CO2 reduction.

6.
BMC Infect Dis ; 22(1): 109, 2022 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-35100983

RESUMEN

BACKGROUND: Internal migrants have an enormous impact on tuberculosis (TB) epidemic in China. Zhejiang Province, as one of the developed areas, also had a heavy burden caused by TB. METHODS: In this study, we collected all cases in Zhejiang Province through the TB Management Information System from 2013 to 2017. Description analysis and Spatio-temporal analysis using R software and ArcGIS were performed to identify the epidemiological characteristics and clusterings, respectively. RESULTS: 48,756 individuals in total were notified with TB among the migrant population (TBMP), accounting for one-third of all cases identified. The primary sources of TB from migrants outside the province were from Guizhou, Sichuan, and Anhui. Wenzhou, Taizhou, and Lishui were the three mainly outflowing cities among the intra-provincial TBMP and Hangzhou as the primarily inflowing city. Also, results implied that the inconsistency of the TBMP in spatial analysis and the border area of Quzhou and Lishui city had the highest risk of TB occurrence among the migrants. Additionally, one most likely cluster and four secondary clusters were identified by the spatial-temporal analysis. CONCLUSION: The effective control of TB in extra-provincial MP was critical to lowering the TB burden of MP in Zhejiang Province. Also, it is suggested that active TB screening for migrant employees outflowed from high epidemic regions should be strengthened, and further traceability analysis needs to be investigated to clarify the mechanism of TB transmission in clustered areas.


Asunto(s)
Migrantes , Tuberculosis , China/epidemiología , Análisis por Conglomerados , Humanos , Análisis Espacio-Temporal , Tuberculosis/epidemiología
7.
Epidemiol Infect ; 149: e79, 2021 03 19.
Artículo en Inglés | MEDLINE | ID: mdl-33736739

RESUMEN

Tuberculosis (TB) is a common infectious disease, and the present study aims to explore the associations of single nucleotide polymorphisms (SNPs) at rs1135216 and rs1057141 of transporter-associated antigen processing (TAP1) and rs2228396 of TAP2 with pulmonary tuberculosis (PTB) risk. A case-control study including 168 smear-positive PTB cases and 251 controls was conducted. Genotyping of the SNPs at rs1135216, rs1057141 and rs2228396 was performed, and their associations with PTB risk were analysed with SPSS software version 19.0. After conducting stratification for age, a significant association was detected for rs1057141 with increased PTB risk (OR = 0.17, 95% CI 0.04-0.79) among those aged ≥60 years. For those aged <60 years, a marginally significant association was detected between rs1135216 TC/CC and PTB risk (OR = 1.97, 95% CI 0.93-4.19). Haplotype analysis revealed that the haplotype AT at rs1135216 and rs2228396, as well as AAT at rs1057141, rs1135216 and rs2228396, was associated with increased PTB risk, and the ORs were 2.83 (95% CI 1.30-6.14) and 2.89 (95% CI 1.34-6.27), respectively. Rs1057141 is a genetic predictor of reduced PTB risk for those aged ≥60 years, while rs1135216 might be a potential genetic predictor for those aged <60 years. Haplotype AT at rs1135216 and rs2228396, as well as AAT at rs1057141, rs1135216 and rs2228396, is a genetic marker that may predict PTB risk.


Asunto(s)
Transportador de Casetes de Unión a ATP, Subfamilia B, Miembro 2/genética , Miembro 3 de la Subfamilia B de Transportadores de Casetes de Unión a ATP/genética , Predisposición Genética a la Enfermedad , Variación Genética , Tuberculosis Pulmonar/epidemiología , Tuberculosis Pulmonar/genética , China/epidemiología , Femenino , Haplotipos , Humanos , Masculino , Persona de Mediana Edad , Oportunidad Relativa
8.
Trop Med Int Health ; 22(10): 1328-1333, 2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-28746979

RESUMEN

OBJECTIVES: The poor detection rate of multidrug-resistant tuberculosis (MDR-TB) highlights the urgent need to explore new case finding model to improve the detection of MDR-TB in China. The aim of this study was to evaluate the feasibility of a new model that combines molecular diagnostics and sputum transportation for early detection of patients with MDR-TB in Zhejiang. METHODS: From May 2014 to January 2015, TB suspects were continuously enrolled at six county-level designated TB hospitals in Zhejiang. Each patient gave three sputum samples, which were submitted to laboratory for smear microscopy, solid culture and GeneXpert. The specimens from rifampin (RIF)-resistant cases detected by GeneXpert, and positive cultures were transported from county-level to prefecture-level laboratories for line probe analysis (LPA) and drug susceptibility testing (DST). The performance and interval of MDR-TB detection of the new model were compared with those of conventional model. RESULTS: A total of 3151 sputum specimens were collected from TB suspects. The sensitivity of GeneXpert for detecting culture-positive cases was 92.7% (405/437), and its specificity was 91.3% (2428/2659). Of 16 RIF-resistant cases detected by DST, GeneXpert could correctly identify 15 cases, yielding a sensitivity of 93.8% (15/16). The specificity of GeneXpert for detecting RIF susceptibility was 100.0% (383/383). The average interval to diagnosis of the conventional DST model was 56.5 days, ranging from 43 to 71 days, which was significantly longer than that of GeneXpert plus LPA (22.2 days, P < 0.01). CONCLUSION: Our data demonstrate that the combination of improved molecular TB tests and sputum transportation could significantly shorten the time required for detection of MDR-TB, which will bring benefits for preventing an epidemic of MDR-TB in this high-prevalence setting.


Asunto(s)
Mycobacterium tuberculosis/genética , Manejo de Especímenes/normas , Tuberculosis Resistente a Múltiples Medicamentos/diagnóstico , Técnicas de Tipificación Bacteriana/métodos , China , Farmacorresistencia Bacteriana Múltiple/efectos de los fármacos , Farmacorresistencia Bacteriana Múltiple/genética , Diagnóstico Precoz , Estudios de Factibilidad , Técnicas de Genotipaje , Humanos , Modelos Biológicos , Técnicas de Diagnóstico Molecular , Reacción en Cadena de la Polimerasa Multiplex , Mycobacterium tuberculosis/efectos de los fármacos , Mycobacterium tuberculosis/aislamiento & purificación , Sensibilidad y Especificidad , Manejo de Especímenes/métodos , Esputo/microbiología , Tuberculosis Resistente a Múltiples Medicamentos/genética
9.
Chem Sci ; 15(10): 3530-3538, 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38455020

RESUMEN

Stimuli-responsive optical materials have provided a powerful impetus for the development of intelligent optoelectronic devices. The family of organic-inorganic hybrid metal halides, distinguished by their structural diversity, presents a prospective platform for the advancement of stimuli-responsive optical materials. Here, we have employed a crown ether to anchor the A-site cation of a chiral antimony halide, enabling convenient control and modulation of its photophysical properties. The chirality-dependent asymmetric lattice distortion of inorganic skeletons assisted by a crown ether promotes the formation of self-trapped excitons (STEs), leading to a high photoluminescence quantum yield of over 85%, concomitant with the effective circularly polarized luminescence. The antimony halide enantiomers showcase highly sensitive stimuli-responsive luminescent behaviours towards excitation wavelength and temperature simultaneously, exhibiting a versatile reversible colour switching capability from blue to white and further to orange. In situ temperature-dependent luminescence spectra, time-resolved luminescence spectra and theoretical calculations reveal that the multi-stimuli-responsive luminescent behaviours stem from distinct STEs within zero-dimensional lattices. By virtue of the inherent flexibility and adaptability, these chiral antimony chlorides have promising prospects for future applications in cutting-edge fields such as multifunctional illumination technologies and intelligent sensing devices.

10.
Mol Genet Genomic Med ; 12(2): e2386, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38337161

RESUMEN

BACKGROUND: Pulmonary tuberculosis (PTB) is a common infectious disease caused by mycobacterium tuberculosis (MTB) and the present study aims to explore the associations of genetic variants within tyrosine kinases 2 (TYK2) with PTB incidence. METHODS: A population-based case control study including 168 smear-positive PTB cases and 251 controls was conducted. Five single nucleotide polymorphisms (SNPs) including rs280520, rs91755, rs2304256, rs12720270, rs280519 located within TYK2 gene were selected and MassARRAY® MALDI-TOF system was employed for genotyping. SPSS 19.0 was adopted for statistical analysis, non-conditional logistic regression was conducted. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were computed to estimate their contributions to PTB incidence. RESULTS: In the overall study population, rs91755 TT and rs280519 AA genotypes were found to be associated with reduced PTB risk (OR = 0.34, 95% CI: 0.16-0.72; OR = 0.38, 95% CI: 0.18-0.79, respectively). After stratification for sex, we found that among the male population, rs91755TG/TT, rs12720270AG/GG and rs280519AG/AA genotypes were associated with reduced PTB risk (OR = 0.41, 95% CI: 0.21-0.80; OR = 0.44, 95% CI: 0.21-0.94; OR = 0.42, 95% CI: 0.21-0.82, respectively). After stratification for age, we found that among those aged <60 years, rs91755TT and rs280519AA genotype were associated with reduced PTB risk (OR = 0.29, 95% CI: 0.09-0.90; OR = 0.34, 95% CI: 0.11-1.08, respectively); while rs2304256AC/AA genotype was associated with increased PTB risk (OR = 2.68, 95% CI: 1.05-6.85). Haplotype analysis revealed that AGAAG and ATCGA (Combined with rs280520, rs91755, rs2304256, rs12720270 and rs280519) were associated with increased (OR = 1.54, 95% CI: 1.01-2.37) and decreased PTB risk (OR = 0.70, 95% CI: 0.52-0.94), respectively. CONCLUSIONS: The genetic variants located within TYK2 including rs91755, rs12720270 and rs280519 were found to be associated with modified PTB risk and the SNPs had potential to be the biomarkers to predict PTB incidence risk.


Asunto(s)
Predisposición Genética a la Enfermedad , Tuberculosis Pulmonar , Humanos , Masculino , Persona de Mediana Edad , Estudios de Casos y Controles , Genotipo , TYK2 Quinasa/genética , Tuberculosis Pulmonar/epidemiología , Tuberculosis Pulmonar/genética , China/epidemiología
11.
Infect Genet Evol ; 121: 105603, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38723983

RESUMEN

In the mountainous, rural regions of eastern China, tuberculosis (TB) remains a formidable challenge; however, the long-term molecular epidemiological surveillance in these regions is limited. This study aimed to investigate molecular and spatial epidemiology of TB in two mountainous, rural counties of Zhejiang Province, China, from 2015 to 2021, to elucidate the recent transmission and drug-resistance profiles. The predominant Lineage 2 (L2) Beijing family accounted for 80.1% of total 532 sequenced Mycobacterium tuberculosis (Mtb) strains, showing consistent prevalence over seven years. Gene mutations associated with drug resistance were identified in 19.4% (103/532) of strains, including 47 rifampicin or isoniazid-resistant strains, eight multi-drug-resistant (MDR) strains, and five pre-extensively drug-resistant (pre-XDR) strains. Genomic clustering revealed 53 distinct clusters with an overall transmission clustering rate of 23.9% (127/532). Patients with a history of retreatment and those infected with L2 strains had a higher risk of recent transmission. Spatial and epidemiological analysis unveiled significant transmission hotspots, especially in densely populated urban areas, involving various public places such as medical institutions, farmlands, markets, and cardrooms. The study emphasizes the pivotal role of Beijing strains and urban-based TB transmission in the western mountainous regions in Zhejiang, highlighting the urgent requirement for specific interventions to mitigate the impact of TB in these unique communities.


Asunto(s)
Mycobacterium tuberculosis , Tuberculosis , Humanos , China/epidemiología , Mycobacterium tuberculosis/genética , Femenino , Masculino , Adulto , Persona de Mediana Edad , Estudios Prospectivos , Incidencia , Tuberculosis/epidemiología , Tuberculosis/transmisión , Tuberculosis/microbiología , Análisis Espacial , Adulto Joven , Adolescente , Anciano , Tuberculosis Resistente a Múltiples Medicamentos/epidemiología , Tuberculosis Resistente a Múltiples Medicamentos/transmisión , Tuberculosis Resistente a Múltiples Medicamentos/microbiología , Epidemiología Molecular , Antituberculosos/farmacología , Genómica/métodos , Filogenia
12.
Nat Commun ; 15(1): 1749, 2024 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-38409130

RESUMEN

The copper (Cu)-catalyzed electrochemical CO2 reduction provides a route for the synthesis of multicarbon (C2+) products. However, the thermodynamically favorable Cu surface (i.e. Cu(111)) energetically favors single-carbon production, leading to low energy efficiency and low production rates for C2+ products. Here we introduce in situ copper faceting from electrochemical reduction to enable preferential exposure of Cu(100) facets. During the precatalyst evolution, a phosphate ligand slows the reduction of Cu and assists the generation and co-adsorption of CO and hydroxide ions, steering the surface reconstruction to Cu (100). The resulting Cu catalyst enables current densities of > 500 mA cm-2 and Faradaic efficiencies of >83% towards C2+ products from both CO2 reduction and CO reduction. When run at 500 mA cm-2 for 150 hours, the catalyst maintains a 37% full-cell energy efficiency and a 95% single-pass carbon efficiency throughout.

13.
Trop Med Int Health ; 18(11): 1392-9, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24107010

RESUMEN

OBJECTIVE: To report care pathways of tuberculosis (TB) patients under the integrated model, where TB clinical service is provided by a general hospital instead of the TB dispensary, with the aim of providing policy recommendations for TB care reforms in China. METHODS: Six counties implementing the integrated model were randomly selected, and 50 TB patients in each county participated in a questionnaire survey. RESULTS: Of the 301 participants, 82 visited only the TB designated hospital. A patient visited a median of two health providers in total. The median external provider delay and internal provider delay were 1 and 0 day, respectively. The median out-of-pocket medical costs were US$379 in total; US$293 in the TB units and US$0 in other health units in the TB designated hospital. Logistic regression analyses suggested that patients who visited the primary care facilities first tended to have longer external delays (OR = 5.71) than patients who visited the other hospitals (OR = 10.16). CONCLUSION: The integrated model is promising as it reported relatively fewer patient pathways and shorter delays than the dispensary model. However, the integrated model did not reduce patient out-of-pocket costs.


Asunto(s)
Unidades Hospitalarias , Hospitales Generales , Manejo de Atención al Paciente/normas , Atención al Paciente/normas , Atención Primaria de Salud , Derivación y Consulta/estadística & datos numéricos , Tuberculosis/terapia , Adulto , Anciano , China , Femenino , Encuestas de Atención de la Salud , Gastos en Salud , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Aceptación de la Atención de Salud , Atención al Paciente/economía , Derivación y Consulta/economía , Derivación y Consulta/normas , Encuestas y Cuestionarios , Tiempo de Tratamiento , Tuberculosis/economía
14.
Inorg Chem ; 52(12): 6969-74, 2013 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-23742023

RESUMEN

Consideration of the material design and components match on structure and energy, the solid-solid combined nanowires of p-type conductive polymer of poly[3-thiophene carboxylic acid methyl ester] (PTCM) and n-type inorganic semiconductor PbS was prepared with a 2.57 µm(2) heterojunction interface. The axial deeply inserting heterojunction nanowire arrays exhibited excellent rectifying features and diode nature, as well as obvious electrical switching behavior, which are much excelled individual components of PTCM and PbS nanowire arrays for realizing synergistic performance.

15.
Phys Chem Chem Phys ; 15(30): 12660-6, 2013 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-23793230

RESUMEN

Two kinds of D-A molecular of (4-(4-(9H-carbazol-9-yl)phenyl))-7-nitrobenzothiadiazole (BSC) and 4-((4-(9H-carbazol-9-yl)phenyl)ethynyl)-7-nitrobenzothiadiazole (BEC) containing carbazole moieties as the donor were synthesized. X-ray crystal data elucidated the multiple intermolecular interactions. They exhibit distinctly different self-assembly behaviours. The nonlinear optical properties were studied using the top-hat Z-scan technique at 532 nm with a 21 ps pulse. The results indicate that they exhibit large third-order nonlinear absorption effects. The nonlinear absorption coefficients α2 fitting the experimental data are 6.3 × 10(-12) m W(-1) for BSC and 3.6 × 10(-11) m W(-1) for BEC. The time-resolved pump-probe results show that both nonlinear absorption and nonlinear refraction of BEC in CH2Cl2 solution have rapid optical responses, which indicate the nonlinear absorption and nonlinear refraction mechanism are excited-state nonlinear. Moreover, both of these two compounds are observed to be aggregation-induced emission (AIE) active. The aggregates of the well-formed one-dimensional microrods of BEC and BSC endow the material with potential applications in the field of optical devices.

16.
Zhong Yao Cai ; 36(3): 349-53, 2013 Mar.
Artículo en Zh | MEDLINE | ID: mdl-24010311

RESUMEN

OBJECTIVE: To optimize the extraction conditions of polysaccharide from Moerella iridescens with the microwave-assisted extraction technology by Response surface methodology (RSM). METHODS: Extracting temperature, extracting time and the solvent/solid ratio were selected as factors. The yield of polysaccharide was used as the responsive value. Based on the single factors experiments, a three-factor-three-level experiments design was developed by Box-Benhken central composite design method. The response surface method was employed to analyze the results of experiments. RESULTS: The optimum extraction conditions of polysaccharide were as follows: extracting temperature was 45 degrees C, extracting time was 2.7 h and solvent/solid ratio was 50:1. The predictive maximum yield of polysaccharide was 1.17%. The average yield of polysaccharide in 3 validation experiments was 1.19% and the relative error was 1.70%. CONCLUSION: RSM analysis optimizing the extraction conditions for polysaccharide from Moerella iridescens is feasible, which can improve the extraction rate of Moerella iridescens polysaccharide.


Asunto(s)
Bivalvos/química , Microondas , Polisacáridos/aislamiento & purificación , Animales , Modelos Estadísticos , Temperatura , Factores de Tiempo , Agua/química
17.
Org Lett ; 25(4): 676-681, 2023 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-36682056

RESUMEN

Herein we describe a method to produce 2-haloalkoxy-3-substituted quinolines via the cyclization of 2-alkynylanilines with TMSCF3 and THF. This synthetic method uses inexpensive and easy-to-handle TMSCF3 and employs a commercially available CuI catalyst to transform a broad range of 2-alkynylanilines into versatile 2-difluoromethoxy-3-substituted quinolines and 2-iodoalkoxy-3-substituted quinolines with excellent chemoselectivity.

18.
JMIR Public Health Surveill ; 9: e49859, 2023 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-37902822

RESUMEN

BACKGROUND: Tuberculous pleurisy (TP) presents a serious allergic reaction in the pleura caused by Mycobacterium tuberculosis; however, few studies have described its spatial epidemiological characteristics in eastern China. OBJECTIVE: This study aimed to determine the epidemiological distribution of TP and predict its further development in Zhejiang Province. METHODS: Data on all notified cases of TP in Zhejiang Province, China, from 2017 to 2021 were collected from the existing tuberculosis information management system. Analyses, including spatial autocorrelation and spatial-temporal scan analysis, were performed to identify hot spots and clusters, respectively. The prediction of TP prevalence was performed using the seasonal autoregressive integrated moving average (SARIMA), Holt-Winters exponential smoothing, and Prophet models using R (The R Foundation) and Python (Python Software Foundation). RESULTS: The average notification rate of TP in Zhejiang Province was 7.06 cases per 100,000 population, peaking in the summer. The male-to-female ratio was 2.18:1. In terms of geographical distribution, clusters of cases were observed in the western part of Zhejiang Province, including parts of Hangzhou, Quzhou, Jinhua, Lishui, Wenzhou, and Taizhou city. Spatial-temporal analysis identified 1 most likely cluster and 4 secondary clusters. The Holt-Winters model outperformed the SARIMA and Prophet models in predicting the trend in TP prevalence. CONCLUSIONS: The western region of Zhejiang Province had the highest risk of TP. Comprehensive interventions, such as chest x-ray screening and symptom screening, should be reinforced to improve early identification. Additionally, a more systematic assessment of the prevalence trend of TP should include more predictors.


Asunto(s)
Tuberculosis Pleural , Masculino , Humanos , Femenino , Tuberculosis Pleural/epidemiología , Análisis Espacio-Temporal , Análisis Espacial , China/epidemiología , Estaciones del Año
19.
Front Public Health ; 11: 1114248, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36844836

RESUMEN

Background: Pulmonary tuberculosis (PTB) is a serious chronic communicable disease that causes a significant disease burden in China; however, few studies have described its spatial epidemiological features in students. Methods: Data of all notified PTB cases from 2007 to 2020 in the student population were collected in the Zhejiang Province, China using the available TB Management Information System. Analyses including time trend, spatial autocorrelation, and spatial-temporal analysis were performed to identify temporal trends, hotspots, and clustering, respectively. Results: A total of 17,500 PTB cases were identified among students in the Zhejiang Province during the study period, accounting for 3.75% of all notified PTB cases. The health-seeking delay rate was 45.32%. There was a decreasing trend in PTB notifications throughout the period; clustering of cases was seen in the western area of Zhejiang Province. Additionally, one most likely cluster along with three secondary clusters were identified by spatial-temporal analysis. Conclusion: Although was a downward trend in PTB notifications among students during the time period, an upward trend was seen in bacteriologically confirmed cases since 2017. The risk of PTB was higher among senior high school and above than of junior high school. The western area of Zhejiang Province was the highest PTB risk settings for students, and more comprehensive interventions should be strengthened such as admission screening and routine health monitoring to improve early identification of PTB.


Asunto(s)
Tuberculosis Pulmonar , Humanos , Tuberculosis Pulmonar/epidemiología , Análisis Espacio-Temporal , Análisis Espacial , China/epidemiología , Estudiantes
20.
ACS Appl Mater Interfaces ; 15(27): 32404-32415, 2023 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-37368238

RESUMEN

In the oxidation reaction of volatile organic compounds catalyzed by metal oxides, distinguishing the role of active metal sites and oxygen mobility at specific preferentially exposed crystal planes and diverse temperatures is challenging. Herein, Co3O4 catalysts with four different preferentially exposed crystal planes [(220), (222), (311), and (422)] and oxygen vacancy formation energies were synthesized and evaluated in styrene complete oxidation. It is demonstrated that the Co3O4 sheet (Co3O4-I) presents the highest C8H8 catalytic oxidation activity (R250 °C = 8.26 µmol g-1 s-1 and WHSV = 120,000 mL h-1 g-1). Density functional theory studies reveal that it is difficult for the (311) and (222) crystal planes to form oxygen vacancies, but the (222) crystal plane is the most favorable for C8H8 adsorption regardless of the presence of oxygen vacancies. The combined analysis of temperature-programmed desorption and temperature-programmed surface reaction of C8H8 proves that Co3O4-I possesses the best C8H8 oxidation ability. It is proposed that specific surface area is vital at low temperature (below 250 °C) because it is related to the amount of surface-adsorbed oxygen species and low-temperature reducibility, while the ratio of surface Co3+/Co2+ plays a decisive role at higher temperature because of facile lattice oxygen mobility. In situ diffuse reflectance infrared Fourier spectroscopy and the 18O2 isotope experiment demonstrate that C8H8 oxidation over Co3O4-I, Co3O4-S, Co3O4-C, and Co3O4-F is mainly dominated by the Mars-van Krevelen mechanism. Furthermore, Co3O4-I shows superior thermal stability (57 h) and water resistance (1, 3, and 5 vol % H2O), which has the potential to be conducted in the actual industrial application.

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