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1.
Ying Yong Sheng Tai Xue Bao ; 31(5): 1487-1495, 2020 May.
Artículo en Chino | MEDLINE | ID: mdl-32530225

RESUMEN

The ENSO events affect climate and fire danger of China. It would be helpful for improving fire danger forecast to understand the impacts of ENSO events on fire weather for various ecological zones in the country. We calculated the fire weather index (FWI) using the daily climatic dataset (V3.0) of international exchange weather stations in China during 1951-2016. The burned areas in forests for each ecological zone in 2001-2016 were derived from MODIS fire products. Temperature, precipitation, FWI and burned areas in fire season were estimated for each ecological zone by ENSO events (weak, medium, strong, and super strong El Niño events and weak, medium, and strong La Niña events). The results showed that there were 19 El Niño events and 14 La Niña events during 1950-2016. The average daily maximum temperature of the spring fire season increased significantly in the northwestern region with the influence of strong or super strong El Niño event, while the temperature reduced significantly in the medium El Niño event for mid-temperate semi-arid grassland. Precipitation in fire season generally increased in El Niño events in southern and southwestern forest regions. It would be reduced in most areas affected by the low and medium intensity La Niña event, but be increased during the strong La Nina event. The fire weather indices of southern forest regions decreased due to the weak El Niño event. The FWI of the northern forest regions increased with the strong or super strong El Niño event, and reduced in the southern and southwestern forest areas. There was a significant spatial difference on the FWI for some ecological zones with the impacts of the El Niño/La Niña events. The burned areas showed a consistent change trend with seasonal severity rating (SSR) during 2001-2016 when the SSR changed significantly for the regions of deciduous broad-leaved forest in humid/semihumid areas of warm temperate zone, broad-leaved forest in the middle north subtropical humid areas, and broad-leaved forest in tropical and subtropical humid areas. The burned areas in the rest regions were not affected by the ENSO events.


Asunto(s)
Incendios Forestales , China , El Niño Oscilación del Sur , Estaciones del Año , Tiempo (Meteorología)
2.
Ying Yong Sheng Tai Xue Bao ; 28(10): 3144-3154, 2017 Oct.
Artículo en Chino | MEDLINE | ID: mdl-29692131

RESUMEN

As an important technical reference for efficient prevention and fighting against forest fire, forest fire behavior parameters are mainly obtained from fire behavior simulators in some deve-loped countries. This study selected two simulators, the Farsite from USA and the Prometheus from Canada, which were both widely used in local area. Through comparing simulated results and relative data of the '3·29 Fire' occurred in Anning City, Southwestern China, we tried to evaluate accuracy of the simulators in a quantitative way. The results indicated that, in the simulation of peri-meter, the precision of Farsite under Scott fuel model was the highest, while Prometheus was the lowest, but the difference was not significant. The difference in simulative perimeter between Farsite and Prometheus mainly concentrated in the distribution area of Pinus yunnanensis. In the simulation of rate of spread (ROS), the mean ROS results of Farsite under both fuel models were close to the actual situation, while the results of Prometheus were far away from the actual situation. The diffe-rent simulative area of ROS between Farsite and Prometheus mainly concentrated in the distribution area of P. yunnanensis. In the simulation of fireline intensity (FLI), the mean FLI results of Farsite under both fuel models were similar, and Prometheus obtained significantly different FLI results from Farsite, while the different simulative area of FLI between Farsite and Prometheus mainly concentrated in the distribution area of Quercus.


Asunto(s)
Ecosistema , Incendios , Canadá , China , Bosques , Árboles
3.
Ying Yong Sheng Tai Xue Bao ; 27(3): 769-776, 2016 Mar.
Artículo en Chino | MEDLINE | ID: mdl-29726181

RESUMEN

Forest fire risk depends on the hazard factors, affected body, and hazard prevention and reduction ability. The integrated risk assessment is the foundation for developing scientific fire mana-gement policies and carrying out the forest fire prevention measures. A forest fire risk assessment model and index system were established based on the classic natural disaster risk model and available data, and the model was used to assess the forest fire risks in past and future. The future climate scenario data included outputs from five global climate models (GFDL-ESM2M, HadGEM2-ES, IPSL-CM5A-LR, MIROC-ESM-CHEM and NorESM1-M) for RCP 2.6, RCP 4.5, RCP 6.0 and RCP 8.5, respectively. Each component index of Fire Weather Index (FWI) system was calculated daily for each grid in 1987-2050 for the historical observations and future climate scenarios according to the maximum temperature, minimum relative humidity, wind speed and daily precipitation. The results showed that areas with high and very high fire danger ratings in 1987-2010 accounted for 21.2% and 6.2%, respectively, which were distributed in Greater Xing'an Mountains and the Changbai Mountain area, most parts of Yunnan, and many fragment areas in southern China. The areas with high and very high burn possibilities were mainly distributed in the northeast and southwest region, accounting for 13.1% and 4.0%, respectively. Compared with the observation period, the areas with high and very high fire danger ratings in 2021-2050 would increase by 0.6%, 5.5%, 2.3%, and 3.5% under RCP 2.6, RCP 4.5, RCP 6.0, and RCP 8.5 respectively, and North China would show significant increase. The regions with high-risk forest fires would also increase due to climate change, with the most significant increase under RCP 8.5 scenario (+1.6%).


Asunto(s)
Cambio Climático , Bosques , Incendios Forestales , China , Desastres , Predicción , Medición de Riesgo , Temperatura , Árboles , Tiempo (Meteorología)
4.
J Nurs Res ; 23(3): 172-80, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25700278

RESUMEN

BACKGROUND: Community nurses are an important component of the community health service system. Job burnout among community nurses not only leads to a decline in satisfaction and an increased turnover rate but also may seriously affect the service quality and professional development of nurses. PURPOSE: This study aims to elicit the conditions and factors that cause job burnout in community nurses in Changchun, Jilin Province, China. METHODS: A questionnaire survey was administered to 420 registered nurses in Changchun using a convenience sampling method. RESULTS: Job burnout was found in 362 community nurses (86.2%), with a total mean job burnout score of 2.27 ± 0.65 points. Job burnout was related to marital status, educational level, job satisfaction, and interpersonal relationship difficulties. CONCLUSIONS: These results indicate that community nurses have a high rate of job burnout. Experts should be employed to train nurses in interpersonal communication skills. The community working environment should also be improved.


Asunto(s)
Agotamiento Profesional , Enfermería en Salud Comunitaria , Personal de Enfermería/psicología , Adulto , China , Femenino , Humanos , Masculino
5.
Ying Yong Sheng Tai Xue Bao ; 25(11): 3279-86, 2014 Nov.
Artículo en Chino | MEDLINE | ID: mdl-25898627

RESUMEN

Climate, vegetation and human activities have influences on regional fire regimes. To understand the fire regimes for ecological zones on national scale is the base for carrying on the forest fire management. Daily observed temperature and precipitation data in 1961-2010 were interpolated into grids for China mainland with spatial resolution of 0.250 x 0.250, which was used to analyze their changes in fire season for eight ecological zones. Mann-Kendall test method was used for trend analysis of climate and fire dynamics. The results indicated that the average temperature for the areas with forests showed a significant linear upward trend in 1961-2010, but the precipitation didn't have the tendency. The average temperature in fire season for all the ecological zones increased significantly in the study period, and the most increment occurred in temperate semi-arid/arid steppe regions. There was no significant change in precipitation in fire season for most regions. Forest fire numbers for the mainland showed obvious fluctuations, but the affected forest areas decreased significantly. The curves of fire numbers and affected forest areas showed a bimodal shape for all ecological zones, except those showed a significant increase in the coniferous forest region in the temperate arid areas.


Asunto(s)
Clima , Incendios , Bosques , Temperatura , China , Cambio Climático , Ecología , Estaciones del Año
6.
Int J Med Sci ; 10(10): 1301-6, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23983589

RESUMEN

BACKGROUND: The Nemo-like kinase (NLK) is a serine/threonine-protein kinase that involved in a number of signaling pathways regulating cell fate. Variation of NLK has been shown to be associated with the risk of cancer. However, the function of NLK in oral adenosquamous carcinoma cells line CAL-27 is unknown. METHODS: In this study, we evaluated the function of NLK in CAL-27 cells by using lentivirus-mediated RNA silence. The targeted gene expression, cell proliferation and cell cycle are investigated by RT-PCR, western-blot, MTT method, colony forming assay and flow cytometry analysis respectively. RESULTS: After NLK silencing, the number of colonies was significantly reduced (54 ± 5 colonies/well compared with 262 ± 18 colonies/well in non-infected or 226 ± 4 colonies/well in negative control group (sequence not related to NLK sequence with mismatched bases). Using crystal violet staining, we also found that the cell number per colony was dramatically reduced. The RNA silencing of NLK blocks the G0/G1 phase to S phase progression during the cell cycle. CONCLUSIONS: These results suggest that NLK silencing by lentivirus-mediated RNA interference would be a potential therapeutic method to control oral squamous carcinoma growth.


Asunto(s)
Carcinoma Adenoescamoso/enzimología , Fase G1/fisiología , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Lentivirus/genética , Proteínas Serina-Treonina Quinasas/metabolismo , Interferencia de ARN/fisiología , Fase de Descanso del Ciclo Celular/fisiología , Fase S/fisiología , Línea Celular Tumoral , Proliferación Celular , Fase G1/genética , Humanos , Péptidos y Proteínas de Señalización Intracelular/genética , Proteínas Serina-Treonina Quinasas/genética , Fase de Descanso del Ciclo Celular/genética , Fase S/genética
7.
Ying Yong Sheng Tai Xue Bao ; 24(3): 853-60, 2013 Mar.
Artículo en Chino | MEDLINE | ID: mdl-23755505

RESUMEN

Cold temperate wetland plays an important role in maintaining regional ecological balance. Fire is an important disturbance factor in wetland ecosystem. Severe burning can induce the marked degradation of the ecological functions of wetland ecosystem. The vegetation restoration, especially the early vegetation restoration, after fires, is the premise and basis for the recovery of the ecological functions of the ecosystem. This paper reviewed the research progress on the factors affecting the vegetation restoration after fires in wetlands. The vegetation restoration after fires in cold temperate wetlands was controlled by the fire intensity, fire size, vegetation types before fires, regeneration characteristics of plant species, and site conditions. It was considered that the long-term monitoring on the post-fire vegetation restoration in cold temperate wetland, the key factors affecting the vegetation restoration, the roles of frozen soil layer on the post-fire vegetation restoration, and the theories and technologies on the vegetation restoration would be the main research directions in the future.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Incendios , Desarrollo de la Planta , Humedales , Frío
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