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1.
Environ Technol ; 42(27): 4317-4323, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32290784

RESUMEN

In the present study, the H2S photolysis using the self-made high-frequency discharge electrodeless lamp (light distribution was 90% at 254 nm and 10% at 185 nm) was studied and simulated by MATLAB software. Firstly, the effects of the initial H2S concentration, irradiation time, oxygen content and relative humidity on H2S photolysis efficiency were experimentally investigated. The results indicated that the photolysis efficiency decreased from 100% to 90.13% with the increase in the initial concentration from 3 to 30 mg/m3, and the main product was H2SO4. With the relative humidity increased from 0% to 99%, H2S photolysis efficiency was obviously improved under different atmospheres (O2 > air > Ar), indicating the significant effect of relative humidity and oxygen concentration. The simulation results were consistent with the experimental results, indicating the feasibility of the simulation model. Moreover, based on the photoreactions, model simulation and equilibrium analysis of sulphur species, the photodegradation pathway of H2S was further inferred. H2S was oxidized to H2SO4 by O3 and other strong oxidizing radicals excited by 185 nm UV light.


Asunto(s)
Rayos Ultravioleta , Oxidación-Reducción , Fotólisis
2.
Neural Regen Res ; 14(8): 1419-1429, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30964068

RESUMEN

Previous studies on brain functional connectivity networks in children have mainly focused on changes in function in specific brain regions, as opposed to whole brain connectivity in healthy children. By analyzing the independent components of activation and network connectivity between brain regions, we examined brain activity status and development trends in children aged 3 and 5 years. These data could provide a reference for brain function rehabilitation in children with illness or abnormal function. We acquired functional magnetic resonance images from 15 3-year-old children and 15 5-year-old children under natural sleep conditions. The participants were recruited from five kindergartens in the Nanshan District of Shenzhen City, China. The parents of the participants signed an informed consent form with the premise that they had been fully informed regarding the experimental protocol. We used masked independent component analysis and BrainNet Viewer software to explore the independent components of the brain and correlation connections between brain regions. We identified seven independent components in the two groups of children, including the executive control network, the dorsal attention network, the default mode network, the left frontoparietal network, the right frontoparietal network, the salience network, and the motor network. In the default mode network, the posterior cingulate cortex, medial frontal gyrus, and inferior parietal lobule were activated in both 3- and 5-year-old children, supporting the "three-brain region theory" of the default mode network. In the frontoparietal network, the frontal and parietal gyri were activated in the two groups of children, and functional connectivity was strengthened in 5-year-olds compared with 3-year-olds, although the nodes and network connections were not yet mature. The high-correlation network connections in the default mode networks and dorsal attention networks had been significantly strengthened in 5-year-olds vs. 3-year-olds. Further, the salience network in the 3-year-old children included an activated insula/inferior frontal gyrus-anterior cingulate cortex network circuit and an activated thalamus-parahippocampal-posterior cingulate cortex-subcortical regions network circuit. By the age of 5 years, nodes and high-correlation network connections (edges) were reduced in the salience network. Overall, activation of the dorsal attention network, default mode network, left frontoparietal network, and right frontoparietal network increased (the volume of activation increased, the signals strengthened, and the high-correlation connections increased and strengthened) in 5-year-olds compared with 3-year-olds, but activation in some brain nodes weakened or disappeared in the salience network, and the network connections (edges) were reduced. Between the ages of 3 and 5 years, we observed a tendency for function in some brain regions to be strengthened and for the generalization of activation to be reduced, indicating that specialization begins to develop at this time. The study protocol was approved by the local ethics committee of the Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences in China with approval No. SIAT-IRB-131115-H0075 on November 15, 2013.

3.
J Huazhong Univ Sci Technolog Med Sci ; 35(3): 333-336, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26072069

RESUMEN

Non-alcoholic fatty liver disease (NAFLD) is a common liver disease and it represents the hepatic manifestation of metabolic syndrome, which includes type 2 diabetes mellitus (T2DM), dyslipidemia, central obesity and hypertension. Glucagon-like peptide-1 (GLP-1) analogues and dipeptidyl peptidase-4 (DPP-4) inhibitors were widely used to treat T2DM. These agents improve glycemic control, promote weight loss and improve lipid metabolism. Recent studies have demonstrated that the GLP-1 receptor (GLP-1R) is present and functional in human and rat hepatocytes. In this review, we present data from animal researches and human clinical studies that showed GLP-1 analogues and DPP-4 inhibitors can decrease hepatic triglyceride (TG) content and improve hepatic steatosis, although some effects could be a result of improvements in metabolic parameters. Multiple hepatocyte signal transduction pathways and mRNA from key enzymes in fatty acid metabolism appear to be activated by GLP-1 and its analogues. Thus, the data support the need for more rigorous prospective clinical trials to further investigate the potential of incretin therapies to treat patients with NAFLD.


Asunto(s)
Inhibidores de la Dipeptidil-Peptidasa IV/uso terapéutico , Péptido 1 Similar al Glucagón/agonistas , Hipoglucemiantes/uso terapéutico , Enfermedad del Hígado Graso no Alcohólico/tratamiento farmacológico , Animales , Ensayos Clínicos como Asunto , Inhibidores de la Dipeptidil-Peptidasa IV/farmacología , Humanos , Hipoglucemiantes/farmacología , Metabolismo de los Lípidos/efectos de los fármacos , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Triglicéridos/metabolismo
5.
Appl Biochem Biotechnol ; 175(7): 3258-70, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25820294

RESUMEN

Denitrifying phosphorus removal is an attractive wastewater treatment process due to its reduced carbon source demand and sludge minimization potential. In the present study, the metagenome of denitrifying phosphorus removal sludge from a lab-scale anaerobic-anoxic SBR was generated by Illumina sequencing to study the microbial community. Compared with the aerobic phosphorus removal sludge, the denitrifying phosphorus removal sludge demonstrated quite similar microbial community profile and microbial diversity with sludge from Aalborg East EBPR WWTP. Proteobacteria was the most dominant phylum; within Proteobacteria, ß-Proteobacteria was the most dominant class, followed by α-, γ-, δ-, and ε-Proteobacteria. The genes involved in phosphate metabolism and biofilm formation reflected the selective pressure of the phosphorus removal process. Moreover, ppk sequence from DPAO was outside the Accumulibacter clusters, which suggested different core phosphorus removal bacteria in denitrifying and aerobic phosphorus removal systems. In a summary, putative DPAO might be a novel genus that is closely related between Accumulibacter and Dechloromonas within Rhodocyclus. The microbial community and metabolic profiles achieved in this study will eventually help to improve the understanding of key microorganisms and the entire community in order to improve the phosphorus removal efficiency of EBPR processes.


Asunto(s)
Betaproteobacteria/genética , Reactores Biológicos , Metagenoma/genética , Biopelículas/crecimiento & desarrollo , Desnitrificación/genética , Metagenómica , Fosfatos/metabolismo , ARN Ribosómico 16S/genética , Aguas del Alcantarillado/microbiología , Aguas Residuales/microbiología
6.
Microbes Environ ; 29(3): 261-8, 2014 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-24964811

RESUMEN

Denitrifying phosphorus removal is an attractive wastewater treatment process due to its reduced carbon source demand and sludge minimization potential. Two lab-scale sequencing batch reactors (SBRs) were operated in alternating anaerobic-anoxic (A-A) or anaerobic-oxic (A-O) conditions to achieve denitrifying enhanced biological phosphate removal (EBPR) and traditional EBPR. No significant differences were observed in phosphorus removal efficiencies between A-A SBR and A-O SBR, with phosphorus removal rates being 87.9% and 89.0% respectively. The community structures in denitrifying and traditional EBPR processes were evaluated by high-throughput sequencing of the PCR-amplified partial 16S rRNA genes from each sludge. The results obtained showed that the bacterial community was more diverse in A-O sludge than in A-A sludge. Taxonomy and ß-diversity analyses indicated that a significant shift occurred in the dominant microbial community in A-A sludge compared with the seed sludge during the whole acclimation phase, while a slight fluctuation was observed in the abundance of the major taxonomies in A-O sludge. One Dechloromonas-related OTU outside the 4 known Candidatus "Accumulibacter" clades was detected as the main OTU in A-A sludge at the stationary operation, while Candidatus "Accumulibacter" dominated in A-O sludge.


Asunto(s)
Bacterias/metabolismo , Restauración y Remediación Ambiental/métodos , Fósforo/metabolismo , Bacterias/clasificación , Bacterias/genética , Bacterias/aislamiento & purificación , Biodegradación Ambiental , Biodiversidad , Reactores Biológicos/microbiología , Desnitrificación , Datos de Secuencia Molecular , Oxígeno/metabolismo , Filogenia , Aguas del Alcantarillado/microbiología
8.
Artículo en Chino | MEDLINE | ID: mdl-22808544

RESUMEN

OBJECTIVE: To evaluate the comprehensive workplace health promotion intervention effect in a pharmaceutical company. METHODS: The evaluation was conducted by using questionnaires, access to information, on-site surveys, satisfaction surveys and interviews. RESULTS: After the intervention, the awareness rate of the staff on "Occupational Disease Prevention Law", occupational disease prevention measures, the definition of hypertension, HIV transmission and high blood pressure, coronary heart disease preventive measures, have been raised from 72.4%, 13.8%, 67.5%, 45.8%, 51.7% to 97.8%, 19.9%, 82.3%, 94.7%, 53.1% respectively. The lifestyle of the staff has been improved, the improvement rate of smoking, drinking, having breakfast 4 times a week and above are 98.5%, 70.2% and 30.6% separately. Out of the 47 evaluation indicators, 41 meet the requirements, 5 basically meet the requirements. CONCLUSION: After implementing workplace health promotion activities, the level of occupational safety and health management of the pharmaceutical company has been enhanced, the physical and mental health of the staff have been promoted. The WHP comprehensive interventions are feasible and effective.


Asunto(s)
Promoción de la Salud , Salud Laboral , Lugar de Trabajo , Industria Farmacéutica , Humanos , Encuestas y Cuestionarios
12.
Artículo en Chino | MEDLINE | ID: mdl-21241564

RESUMEN

OBJECTIVE: To compare and analyze the all previous censuses and large-scale surveys on occupational hazard in China, draw lessons from the past, and try to provide references for the development of census or surveys on the occupational hazard in the new period. METHODS: A literature retrieval had been performed mainly on the occupational hazard census and large-scale surveys since the founding of People's Republic of China. Only the survey items carried on a national scale were selected. Some keywords were drawn from these items such as survey time, survey scope, industries, occupational diseases and the rate of examination, organization and technical director, methods and so on. The outcomes and experiences were summarized. RESULTS: Since the founding of People's Republic of China, there were seven occupational hazard census and large-scale surveys carried in China, three of them were about silicosis or pneumoconiosis, two of them were about poison and carcinogens, one was about noise, another one was about the township industrial enterprises. CONCLUSION: Leadership attention was the fundamental guarantee of the success of the survey, sound occupational health management organizations were the base, collaborative relationship with each other was an import factor, and only the interdisciplinary team, scientific design, quality control and incentive mechanism could assure the quality of the survey. The survey should be designed and carried out according to industries.


Asunto(s)
Enfermedades Profesionales/epidemiología , Servicios de Salud del Trabajador/estadística & datos numéricos , China/epidemiología , Humanos
15.
Sci Total Environ ; 396(1): 34-41, 2008 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-18387653

RESUMEN

1,1,1-trichloro-2,2'-bis(4-chlorophenyl)ethane (DDT) exhibits its long persistence in the environment, unusual bioaccumulation, effects on wildlife, and the possibility of long-term adverse effects on human health, especially reproductive toxicity. Despite the prohibition of most persistent organochlorine pesticides in China, the presence of organochlorine residue, including DDT, has been widely indicated in environmental substance. However, scarce information is available about accumulative levels of DDT in human tissues in China. To evaluate levels of DDT and its potential effects on women and children's health in a Chinese pesticide-exposed area, we recruited 50 pairs of mother-child and 50 postpartum women, and determined the levels of total DDT and its four main metabolites (p,p'-DDE, p,p'-DDT, p,p'-DDD, o,p'-DDT) in venous blood, breast milk and umbilical blood cord by gas chromatography. Accordingly, data on reproductive outcomes of mothers and postpartum women and healthy status of children and infants were gathered through a questionnaire and medical examinations. Furthermore, we also assayed the DDT levels of some environmental samples (soil, food, milk, et al.). The levels of DDT in children's blood were higher than that in the women's. As compared to breast milk, the umbilical blood cord and the ventral fat individually demonstrated a significantly lower and higher level of DDT in the postpartum women. DDT was lower in milk and crucian carp than in the soil near the chemical plant. p,p'-DDT and p,p'-DDE were the main metabolites of DDT. Our findings suggested the cumulative effect of DDT in human body in Tianjin, China.


Asunto(s)
DDT/toxicidad , Exposición a Riesgos Ambientales , Transmisión Vertical de Enfermedad Infecciosa , Exposición Materna , Plaguicidas/toxicidad , Periodo Posparto , Adulto , Niño , Preescolar , China , Estudios Transversales , DDT/sangre , DDT/farmacocinética , Femenino , Sangre Fetal/química , Humanos , Lactante , Recién Nacido , Leche Humana/química , Madres , Plaguicidas/sangre , Plaguicidas/farmacocinética , Encuestas y Cuestionarios
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