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1.
Ying Yong Sheng Tai Xue Bao ; 35(2): 354-362, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38523092

ABSTRACT

Forest fires have a significant impact on human life, property safety, and ecological environment. Deve-loping high-quality forest fire risk maps is beneficial for preventing forest fires, guiding resource allocation for firefighting, assisting in fire suppression efforts, and supporting decision-making. With a multi-criteria decision analysis (MCDA) method based on geographic information systems (GIS) and literature review, we assessed the main factors influencing the occurrences of forest fires in Youxi County, Fujian Province. We analyzed the importance of each fire risk factor using the analytic network process (ANP) and assigned weights, and evaluated the sub-standard weights using fuzzy logic assessment. Using ArcGIS aggregation functions, we generated a forest fire risk map and validated it with satellite fire points. The results showed that the areas classified as level 4 or higher fire risk accounted for a considerable proportion in Youxi County, and that the central and northern regions were at higher risk. The overall fire risk situation in the county was severe. The fuzzy ANP model demonstrated a high accuracy of 85.8%. The introduction of this novel MCDA method could effectively improve the accuracy of forest fire risk mapping at a small scale, providing a basis for early fire warning and the planning and allocation of firefighting resources.


Subject(s)
Fuzzy Logic , Wildfires , Humans , Fires/prevention & control , Forests , Geographic Information Systems , Trees , Wildfires/statistics & numerical data
2.
Ying Yong Sheng Tai Xue Bao ; 31(2): 399-406, 2020 Feb.
Article in Chinese | MEDLINE | ID: mdl-32476331

ABSTRACT

Understanding the changes and driving factors of forest fire can provide scientific basis for prevention and management of forest fire. In this study, we analyzed the changes and driving factors of forest fire in Zhejiang Province during 2001-2016 based on trend analysis and Logistic regression model with the MODIS satellite fire point data combined with meteorological (daily ave-rage wind speed, daily average temperature, daily relative humidity, daily temperature difference, daily cumulative precipitation), human activities (distance from road, distance from railway, distance from resident, population, per capita GDP), topographic and vegetation factors (elevation, slope, vegetation coverage). The results showed that the number of forest fires in spring and summer had significantly increased, while the forest fires in the autumn and winter increased first and then decreased. Forest fire in autumn significantly declined. The four seasons' fire occurrence prediction models had good prediction accuracy, reaching 75.8% (spring), 79.1% (summer), 74.7% (autumn) and 79.6% (winter). The meteorological, human activity, topographic and vegetation factors significantly affected fire occurrence in spring and summer, while meteorological factors were the main fire drivers in autumn and winter in Zhejiang. The focus of forest fire management should be on human activities. Fire prevention campaign should be done in spring and summer when high-risk forest fires were scattered in the study area. In autumn and winter, observatory and monitoring equipment could be built to facilitate fire management and detect in the area of high fire risk that was concentrated in the southwest region.


Subject(s)
Fires , Wildfires , China , Climate , Humans , Seasons
3.
Ying Yong Sheng Tai Xue Bao ; 30(12): 4361-4368, 2019 Dec.
Article in Chinese | MEDLINE | ID: mdl-31840483

ABSTRACT

With the intensification of climate change and human activities, megafires frequently occur, with serious impacts on ecosystems, atmospheric environment, and human health. The United States has accumulated a large amount of practical experience in forest fire management. A comprehensive review of the framework of forest fire management in the United States can provide an inspiring reference for forest fire prevention in China. Starting from the process of historical evolution of forest fire policy, we systematically introduced the four stages of policy evolution and the characteristics of each stage in the US. Moreover, a comprehensive analysis of forest fire management situation in the US from four aspects was conducted, including the management of combustible fuels, administrative responsibility, fire suppression and forest fire management research support. We summarized relevant literature and proposed improvement strategies for future combustibles management, policy politics and fire fighting in the United States. Through the comprehensive analysis of forest fire management in the United States, we put forward some inspiring opinions on forest fire management in China to promote the establishment of a sound forest fire management system with Chinese characteristics.


Subject(s)
Fires , Wildfires , China , Ecosystem , Forests , Humans , Trees , United States
4.
Lipids Health Dis ; 17(1): 239, 2018 Oct 17.
Article in English | MEDLINE | ID: mdl-30326894

ABSTRACT

BACKGROUND: Although there were many studies reporting the combination therapy of Ezetimibe and Atorvastatin's efficacy and Atorvastatin monotherapy's, the conclusions were controversial. Therefore, a systematic review and meta analysis of combination therapy and monotherapy were conducted. METHODS: PubMed, Cochrane Library and Embase were searched for studies of the combination therapy of Ezetimibe and Atorvastatin and Atorvastatin monotherapy published up to October 20, 2017. Two investigators assessed the articles for eligibility and evaluated quality.The changed values and the efficacy of low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), Total Cholesterol (TC) and Triglyceride (TG) indicators were the outcomes. Four doses of the comparisons were included: the combination therapy of Ezetimibe (10 mg) and Atorvastatin (10 mg) (E10 + A10) versus Atorvastatin (20 mg) monotherapy (A20); E10 + A10 vs. A10; E10 + A20 vs. A40; E10 + A40 vs. A80. Review manager software 5.1 was used for quality assessment and Stata version 12.0 software was used for statistical analysis. RESULTS: eventeen studies (11 publications) were included in the meta analysis. Compared with Atorvastatin monotherapy, the overall efficacy of combination therapy of Ezetimibe and Atorvastatin on lowering LDL-C (MD = - 15.38, 95% CI: -16.17 to - 14.60; I2 = 26.2%, n = 17), TC (MD = - 9.51, 95% CI: -10.28 to - 8.74; I2 = 33.7%, n = 17) and TG (MD = - 6.42, 95% CI: -7.78 to - 5.06; I2 = 0%, n = 15) and raising HDL-C (MD = 0.95, 95% CI: 0.34 to 1.57; I2 = 0%, n = 17) was significant. The efficacy of the comparison on HDL-C was largely significant for the different doses. CONCLUSIONS: The overall efficacy and subgroup's efficacy of combination therapy of Ezetimibe and Atorvastatin on lowering LDL-C, TC and TG was significantly better than Atorvastatin monotherapy's. The overall and the E10 + A10/A20 group's effectiveness of combination therapy on rasing HDL-C were significantly.


Subject(s)
Atorvastatin/therapeutic use , Drug Therapy, Combination , Ezetimibe/therapeutic use , Hypercholesterolemia/drug therapy , Cholesterol, HDL/blood , Cholesterol, LDL/blood , Female , Humans , Hypercholesterolemia/blood , Hypercholesterolemia/pathology , Male , Triglycerides/blood
5.
Sleep Med ; 32: 66-74, 2017 Apr.
Article in English | MEDLINE | ID: mdl-28366344

ABSTRACT

OBJECTIVES: Suboptimal sleep duration has been considered to increase the risk of stroke incidence. Thus we aimed to conduct a dose-response meta-analysis to examine the association between sleep duration and stroke incidence. METHODS: We searched PubMed, Web of science and the Cochrane Library to identify all prospective studies evaluating the association of sleep duration and nonfatal and/or fatal stroke incidence. Then, restricted cubic spline functions and piecewise linear functions were used to evaluate the nonlinear and linear dose-response association between them. RESULTS: We included a total of 16 prospective studies enrolling 528,653 participants with 12,193 stroke events. Nonlinear dose-response meta-analysis showed a J-shaped association between sleep duration and total stroke with the lowest risk observed with sleeping for 7 h. Considering people sleeping for 7 h as reference, long sleepers had a higher predicted risk of total stroke than short sleepers [the pooled risk ratios (95% confidence intervals): 4 h: 1.17 (0.99-1.38); 5 h: 1.17 (1.00-1.37); 6 h: 1.10 (1.00-1.21); 8 h: 1.17 (1.07-1.28); 9 h: 1.45 (1.23-1.70); 10 h: 1.64 (1.4-1.92); pnonlinearity<0.001]. Short sleep durations were only significantly associated with nonfatal stroke and with total stroke in the subgroups of structured interview and non-Asian countries. Additionally, we found a slightly decreased risk of ischemic stroke among short sleepers. For piecewise linear trends, compared to 7 h, every 1-h increment of sleep duration led to an increase of 13% [the pooled risk ratios (95% confidence intervals): 1.13 (1.07-1.20); p < 0.001] in risk of total stroke. CONCLUSION: Both in nonlinear and piecewise linear dose-response meta-analyses, long sleep duration significantly increased the risk of stroke incidence.


Subject(s)
Sleep , Stroke/epidemiology , Cohort Studies , Humans , Incidence , Prospective Studies , Risk Factors , Time Factors
6.
Medicine (Baltimore) ; 96(14): e6569, 2017 Apr.
Article in English | MEDLINE | ID: mdl-28383437

ABSTRACT

BACKGROUND: A number of studies had reported the association between tumor necrosis factor-alpha (TNF-α) gene polymorphisms and ischemic heart disease (IHD) risk. However, the results remained controversial. Therefore, we performed a systematic review with multiple meta-analyses to provide the more precise estimations of the relationship. METHODS: We systematically searched electronic databases (PubMed, the Web of Science, EMBASE, Medline, Chinese National Knowledge Infrastructure, WanFang and ChongQing VIP Database) for relevant studies published up to February 2017. The odds ratios (ORs) and 95% confidence intervals (CIs) were estimated for assessing the association. The present meta-analysis was performed using STATA 12.0 software. RESULTS: In total, 45 articles with 17,375 cases and 15,375 controls involved were included. Pooled ORs revealed a significant association between TNF-α -308G/A gene polymorphism and IHD (A vs. G: OR = 1.22, 95% CI = 1.10-1.35; (AA + GA) vs. GG: OR = 1.18, 95% CI = 1.03-1.36; (AA vs. (GA+GG): OR = 1.37, 95% CI = 1.08-1.75)), indicating that the TNF-α -308A allele might be an important risk factor for IHD. No association between other TNF-α gene polymorphisms and susceptibility to IHD were observed. No publication bias were found. Sensitivity analyses indicated that our results were stable. CONCLUSION: The present study indicated a possible association between the TNF-α -308G/A gene polymorphism and IHD risk. However, evidence was limited to confirm the role of TNF-α -238G/A, -857C/T, -863C/A, -1031T/C and other TNF-α gene polymorphisms in the risk of IHD.


Subject(s)
Myocardial Ischemia/genetics , Tumor Necrosis Factor-alpha/genetics , Genetic Predisposition to Disease , Humans , Polymorphism, Genetic
7.
Medicine (Baltimore) ; 96(52): e9508, 2017 Dec.
Article in English | MEDLINE | ID: mdl-29384954

ABSTRACT

We aimed to investigate the dose-response associations between chronic kidney disease (CKD), and short and long-term cardiovascular outcomes, to characterize these associations by drawing dose-response curves based on a Chinese rural ST-segment elevation myocardial infarction (STEMI) population.In all, 1067 patients with STEMI were consecutively enrolled from 12 secondary hospitals of China's Liaoning province (from June 2009 to June 2010 and January 2015 to December 2015). The follow-up was regularly performed by telephone. Patients were grouped by estimated glomerular filter rate (eGFR): normal, eGFR ≥90 mL/min/1.73 m; mild CKD, 60 to 90 mL/min/1.73 m; CKD, <60 mL/min/1.73 m. Adjusted logistic or Cox regression models were employed to compare short and long-term cardiovascular outcomes across different eGFR groups. Dose-response curves were plotted using restricted cubic spline functions.About 18.46% of the STEMI patients had CKD. Patients with CKD were more likely to suffer from other comorbidities, but less likely to receive evidence-based therapies. CKD was independently associated with in-hospital mortality and major adverse cardiac events (MACE) as compared with patients with normal renal function (for in-hospital mortality, adjusted odds ratio [OR] 2.39, 95% confidence interval [CI] 1.18-4.85, P = .02; for in-hospital MACE, adjusted OR 2.01, 95% CI 1.09-3.70, P < .01). Likewise, CKD was significantly associated with long-term mortality as well (CKD vs normal, adjusted hazard ratio 2.55, 95% CI 1.17-5.57, P = .02). The dose-response associations between eGFR, and short and long-term cardiovascular outcomes were found to be linear (all with P values for nonlinear associations >.05).CKD is an independent predictor of worse in-hospital and long-term clinical outcomes. The assessment of eGFR is essential to enable risk stratification, tailored therapy, and early and aggressive management.


Subject(s)
Glomerular Filtration Rate , Renal Insufficiency, Chronic/epidemiology , ST Elevation Myocardial Infarction/epidemiology , Adult , Age Factors , Aged , Aged, 80 and over , Biomarkers , Cardiovascular Diseases/epidemiology , China/epidemiology , Comorbidity , Drosophila Proteins , Female , Hospital Mortality , Humans , Hyperlipidemias/epidemiology , Logistic Models , Male , Membrane Proteins , Middle Aged , Prognosis , Proportional Hazards Models , Renal Insufficiency, Chronic/pathology , Rural Population , ST Elevation Myocardial Infarction/mortality , Severity of Illness Index
8.
Appl Opt ; 44(33): 7156-60, 2005 Nov 20.
Article in English | MEDLINE | ID: mdl-16318187

ABSTRACT

We report on a high-power (cw) red laser at 671 nm by intracavity frequency doubling of a double-end-pumped 1342 nm Nd:YVO4 laser based on the nonlinear crystal LiB3O5. A red output power of 3.38 W is obtained for a pump power of 27 W, with corresponding optical-to-optical efficiency of 12.5%. The 671 nm beam is nearly diffraction limited.

9.
Guang Pu Xue Yu Guang Pu Fen Xi ; 24(7): 787-9, 2004 Jul.
Article in Chinese | MEDLINE | ID: mdl-15766071

ABSTRACT

Photoelectrons plays an important role in the latent image formation process of silver halide materials, and the decay characteristic of photoelectrons are dependent on the structure of silver halide microcrystals to a great extent. In this paper, the decay spectra of free photoelectrons and shallow-trapped electrons were obtained by optics and microwave double resonance technology. The depth and density of electron traps in silver halide microcrystals were discussed. Moreover, using the lifetime of free photoelectrons, the optimal doping amount of shallow electron trap dopants was found by analyzing the distribution condition of electron traps in silver halide.

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