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1.
J Evid Based Med ; 6(3): 157-66, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24325372

RESUMEN

BACKGROUND: Managing compliance in a clinical research, especially in a multi-centre randomized clinical trial (MRCT) is vital. We now feel the need to take a look at the once overlooked area of investigator compliance as it may provide resources necessary for producing satisfactory trial outcomes. OBJECTIVES: To analyze investigator performance and examine their adherence behavior using data collected and information gained from the MISPS-TCM, a Chinese national research project. METHODS: Four researchers were responsible for collecting relevant information and investigating the compliance behavior of participants in MISPS-TCM. The Data Management Committee of MISPS-TCM offered us the number of withdrawal at each site and other site information. Reports on investigator compliance events were provided by the Monitoring Committee. Records of any misconduct of or errors made by the investigator were collected from the Center's daily management diary. Other information sources included trial managers and investigators at the Center or at different sites of the study. RESULTS: Investigator compliance can be an important determinant of trial outcomes and the degree of compliance may have detrimental effects on the reliability of findings of an MRCT, directly or indirectly. CONCLUSIONS: Trial managers of future MRCTs should take a firm grip on investigator compliance from the following aspects. First, physicians should be provided with more opportunities. Second, we created and recommended the 'Five Step Method' for evaluating investigators. Third, measures must be taken to secure investigator compliance. Fourth, evaluation of investigator compliance in an MRCT needs to be made.


Asunto(s)
Ensayos Clínicos como Asunto , Adhesión a Directriz , Investigadores , Conducta Cooperativa , Quimioterapia , Medicina Basada en la Evidencia , Humanos , Control de Calidad
2.
Environ Monit Assess ; 180(1-4): 303-11, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21210216

RESUMEN

In this study, 16 polycyclic aromatic hydrocarbons (PAHs) were detected in sewage sludge samples from four wastewater treatment plants (WWTPs) in Qingdao, China. These WWTPs differ in the type of treatment used and in the origin of the wastewater. The total amounts of PAHs in digested sludges ranged from 1.9645 to 6.5752 mg/kg, which did not exceed the projected European Union cut-off limits (6 mg/kg) for sludge found in farmland, except for the Haibohe WWTP. Significant differences were observed in overall PAH values between WWTPs receiving domestic effluents and those receiving industrial effluents. The total amounts of PAHs in digested sludge from the Licunhe and Haibohe WWTPs, which mainly received industrial effluents, were markedly higher than those of the Tuandao and Huangdao WWTPs, which received only domestic effluents. The distribution of PAH compounds in digested sludges were analysed. At the Tuandao, Huangdao and Licunhe WWTPs, 2-, 3-, 4-benzene rings were predominant, accounting for 100%, 99.8% and 99.0% of the sum concentration of 16 PAHs (∑PAHs), respectively. At the Haibohe WWTP, a large number of high molecular weight PAHs (5-, 6-benzene rings) were observed, accounting for 30% of the ∑PAHs. The sum of seven carcinogenic PAHs (∑PAHs-c) ranged from 0.8694 to 3.0389 mg/kg in four WWTPs. The highest value was found in the Haibohe WWTP. Moreover, the PAH concentrations in sludges from the different treatment processes in the Licunhe and Tuandao WWTPs are discussed.


Asunto(s)
Hidrocarburos Policíclicos Aromáticos/análisis , Aguas del Alcantarillado/análisis , Contaminantes Químicos del Agua/análisis , China , Monitoreo del Ambiente , Eliminación de Residuos Líquidos , Contaminación Química del Agua/estadística & datos numéricos
3.
Huan Jing Ke Xue ; 29(5): 1308-12, 2008 May.
Artículo en Chino | MEDLINE | ID: mdl-18624198

RESUMEN

The biofilm process using a new-type elasticity plastic filler was adopted in a typical polluted stream entering the Tai Lake (the Linzhuanggang). The experiments at pilot scale ran for about 0.5 years. Results show the average removal percentage of permanganate index by biofilm attached to the elasticity plastic filler is about 5.4%, the biggest removal percentage is 9.9%, the average removal percentage of NH(4+) -N is approximately 5.35%-39.91%, the biggest removal percentage of TP is 28.6%. And the bacteriological experimental results show there is the same change laws between the removal percentage of permanganate index and the numbers of heterotrophic bacteria; the numbers of ammonia-oxidizing bacteria (AOB) and nitrite-oxidizing bacteria (NOB) are matching with removal of NH(4+) -N.


Asunto(s)
Agua Dulce/análisis , Contaminantes del Agua/análisis , Purificación del Agua/métodos , Amoníaco/aislamiento & purificación , Amoníaco/metabolismo , Bacterias/crecimiento & desarrollo , Bacterias/metabolismo , Biodegradación Ambiental , Biopelículas , Elasticidad , Filtración/instrumentación , Filtración/métodos , Agua Dulce/microbiología , Nitritos/aislamiento & purificación , Nitritos/metabolismo , Oxidación-Reducción , Plásticos/química
4.
Huan Jing Ke Xue ; 29(10): 2743-8, 2008 Oct.
Artículo en Chino | MEDLINE | ID: mdl-19143364

RESUMEN

The bottom mud in Taihu Lake was simulated indoors in a wave tank. The rules of starting principle of the bottom mud were analyzed under different kinds of disturbing intensity in this paper. The common wave intensity of Tai Lake could be systematically simulated in the wave tank. The critical sheer stress of bottom mud in Tai Lake is 0.050Pa by the experiment. The calculated result of the flow field and suspended solids from the advanced model of FVCOM conforms to the observation data in Taihu Lake very well, which proves validity of the model. Because the conflict of field observation data in time and space greatly influences the accuracy of model parameters, simulating the suspended solids indoors is very important to the cure of Eutrophication in Taihu Lake.


Asunto(s)
Agua Dulce/análisis , Modelos Teóricos , Contaminantes del Agua/análisis , Viento , China , Simulación por Computador , Tamaño de la Partícula
5.
Huan Jing Ke Xue ; 28(9): 1960-4, 2007 Sep.
Artículo en Chino | MEDLINE | ID: mdl-17990539

RESUMEN

The dynamic release of bottom mud in Taihu Lake was simulated indoors in an annular tank. The rules of starting principle, resuspension and release rate of bottom mud were analyzed under different kinds of disturbing intensity. The velocity of flow was basically uniform in the annual tank. Both the rotation rate of the tank and the velocity of flow can be controlled precisely. The relational expression between the release rate of TN, TP (y) and flow velocity (x) was calculated on the basis of the relationship between them. The calculated result from the model of ECOMSED conforms to the observation data in Taihu Lake very well. Because the conflict of field observation data in time and space greatly influences the accuracy of model parameters, simulating the dynamic release of bottom mud indoors is very important to the cure of eutrophication in Taihu Lake.


Asunto(s)
Sedimentos Geológicos/química , Modelos Teóricos , Nitrógeno/análisis , Fósforo/análisis , Contaminantes Químicos del Agua/análisis , China , Monitoreo del Ambiente , Eutrofización , Agua Dulce/análisis , Movimientos del Agua
6.
J Hazard Mater ; 137(3): 1277-83, 2006 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-16716500

RESUMEN

Sludge samples were collected from different treatment steps of Gaobeidian wastewater treatment plant (WWTP) of Beijing City, PR China, to investigate the distributions of total and chemical fractions of Fe, Mn, Ni, Cu, Zn, Cr, Pb, and Mo in different sludges. The highest total concentrations were found for Fe, Mn, Pb, and Mo in digested sludge (DS), Ni and Cr in thickened sludge (TS), Zn in dewatering sludge (DWS), and Cu in active sludge (AS). The lowest concentrations were observed in AS, except for Cu in TS. Significant differences of total metal concentration were observed between AS and TS (or DS), suggesting that sludge thickening and digesting treatments significantly influenced the total metal concentrations. Fe, Cu, Ni, Cr, Mo, and Pb distributed principally in the residual fraction in all sludges, while Zn and Mn presented in a highly available fraction. For same metal in different sludges, the portion of easily mobile fraction decreased significantly along the wastewater treatment process, and metals in AS presented in the highest available fraction. Organic matter contents, TN, and TP of sludges exhibited a significant positive correlation with the concentrations of exchangeable and reducible fraction of Pb, Mo, Cr, Cu, and Fe, while sludge pH demonstrated significant negative correlations with the concentrations of these metals.


Asunto(s)
Metales Pesados/análisis , Metales Pesados/química , Aguas del Alcantarillado/química , Eliminación de Residuos Líquidos , Fenómenos Químicos , Química Física , Eliminación de Residuos Líquidos/instrumentación
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