Based on meteorological data of Zhumadian City in the past 56 years, the damage of flood-causing rainstorm to towns in Zhumadian City as well as its cataclysm form, influencing system, cataclysm characteristics and ac...Based on meteorological data of Zhumadian City in the past 56 years, the damage of flood-causing rainstorm to towns in Zhumadian City as well as its cataclysm form, influencing system, cataclysm characteristics and action mechanism were analyzed to discuss the characteristics and rules of damage caused by flood-causing rainstorm. Meanwhile, countermeasures against flood-causing rainstorm cataclysm in Zhumadian City were proposed to provide scientific references for early warning and monitoring of flood-causing rainstorm as well as flood control and disaster mitigation.展开更多
Flood disasters pose serious threats to human life and property worldwide.Exploring the spatial drivers of flood disasters on a macroscopic scale is of great significance for mitigating their impacts.This study propos...Flood disasters pose serious threats to human life and property worldwide.Exploring the spatial drivers of flood disasters on a macroscopic scale is of great significance for mitigating their impacts.This study proposes a comprehensive framework for integrating driving-factor optimization and interpretability,while considering spatial heterogeneity.In this framework,the Optimal Parameter-based Geographic Detector(OPGD),Recursive Feature Estimation(RFE),and Light Gradient Boosting Machine(LGBM)models were utilized to construct the OPGD–RFE–LGBM coupled model to identify the essential driving factors and simulate the spatial distribution of flood disasters.The SHapley Additive ExPlanation(SHAP)interpreter was employed to quantitatively explain the driving mechanisms behind the spatial distribution of flood disasters.Yunnan Province,a typical mountainous and plateau area in Southwest China,was selected to implement the proposed framework and conduct a case study.For this purpose,a flood disaster inventory of 7332 historical events was prepared,and 22 potential driving factors related to precipitation,surface environment,and human activity were initially selected.Results revealed that flood disasters in Yunnan Province exhibit high spatial heterogeneity,with geomorphic zoning accounting for 66.1%of the spatial variation in historical flood disasters.The OPGD–RFE–LGBM coupled model offers clear advantages over a single LGBM in identifying essential driving factors and quantitatively analyzing their impacts.Moreover,the simulation performance shows a slight improvement(a 6%average decrease in RMSE and an average increase of 1%in R2)even with reduced factor data.Factor explanatory analysis indicated that the combination of the essential driving factor sets varied across different subregions;nevertheless,precipitation-related factors,such as precipitation intensity index(SDII),wet days(R10MM),and 5-day maximum precipitation(RX5day),were the main driving factors controlling flood disasters.This study provides a quantitative analytical framework for the spatial drivers of flood disasters at large scales with significant heterogeneity,offering a reference for disaster management authorities in developing macro-strategies for disaster prevention.展开更多
The seismic intensities, lithologic characteristics and terrain features from a 3000 km2-region near the epicenter of the Lushan earthquake are used to analyze earthquake-induced geological disaster. The preliminary r...The seismic intensities, lithologic characteristics and terrain features from a 3000 km2-region near the epicenter of the Lushan earthquake are used to analyze earthquake-induced geological disaster. The preliminary results indicate that secondary effects of the earthquake will affect specific areas, including those with glutenite and carbonate bedrock, a seismic intensity of IX, slopes between 40° and 50°, elevations of less than 2500 m, slope change rates between 20° and 30°, slope curvatures from - 1 to -0.5 and 0. 5 to 1, and relief between 50 and 100 m. Regions with susceptibility indices greater than 0.71 are prone to landslides and collapses. The secondary features are mainly distributed on both sides of the ridges that extend from Baosheng to Shuangshi and from Baosheng to Longxing. Other features are scattered on both sides of the ridges that extend from Qishuping to Baosheng and from Masangping to Lingguan. The distribution of the earthquake-related features trends in the NE direction, and the area that was most affected by the Lushan earthquake covers approximately 52.4 km^2.展开更多
[ Objective] The research aimed to study climatic characteristics of hail and dsk zoning of its disaster factor in Anhui Province. [Method] Based on the hail-day records from 82 weather stations in Anhui Province, Chi...[ Objective] The research aimed to study climatic characteristics of hail and dsk zoning of its disaster factor in Anhui Province. [Method] Based on the hail-day records from 82 weather stations in Anhui Province, Chinese Meteorologica/Disaster Dictionary （1951 to 2005） and The Yearbook of Meteorological Disaster in Anhui Province （2006 to 2009）, we discussed the climatic characteristic and dsk zoning of hail disaster in Anhui Province. [Result] The hail days exhibited significant interdecadal variability, and it had a significant negative correlation with annual mean minimum temperature. The hail usually occurred from March to August, most frequently in June but less in autumn and winter. It most likely took place from aftemoon to sunset. The spatial distribution showed that the hail occurred more in northeast of Huaibei, south of Dabie Mountain and some areas of Huangshan Mountain, but less in Jianghuai region. The index of hail intensity was defined by three factors, the diameter, duration and gust grade, and the percentile method was used to grade the intensity of the hail disaster. This work provided a possibility for quantitative assessment of the intensity of hail disaster. The results of hail disaster risk zoning in Anhui Province showed that high dsk zones were concentrated in northeast of Huaibei, and low risk zones were mainly in south of Huaihe River. Finally, vedfied by historic disaster, it showed that the results of risk zoning had a certain rationality and feasibility. Conclusion The research could provide reference basis for hail disaster defense and assessment.展开更多
[Objective] The research aimed to analyze temporal and spatial variation of strong precipitation caused flood and agricultural disaster loss in Huaihe River basin of Anhui Province during Meiyu period of 2007.[Method]...[Objective] The research aimed to analyze temporal and spatial variation of strong precipitation caused flood and agricultural disaster loss in Huaihe River basin of Anhui Province during Meiyu period of 2007.[Method] On the basis of rainfalls of each station in Huaihe River basin of Anhui,rainfall data during Meiyu period of 2007 and flood disaster data in the same period,the temporal and spatial distribution characteristics of strong precipitation caused flood during Meiyu period of 2007 and its harm on agriculture were analyzed.The variation rule,distribution characteristics of strong precipitation during Meiyu period in Huaihe River basin of Anhui and its relationship with agricultural disaster loss were discussed.[Result] During Meiyu period of 2007 in Huaihe River basin of Anhui,the rainstorm was more,and the rainfall was large.The precipitation variation showed 'three-peak' trend.Rainfall in Huaihe River basin during Meiyu period of 2007 was greatly more than that homochronously in Yangtze River basin.The rain area over 400.0 mm during Meiyu period mainly located in Huaihe River basin,and the rain area over 600.0 mm mainly located from area along Huaihe River to central Huaibei.The rainfall during Meiyu period gradually decreased toward south and north by the north bank of Huaihe River as the symmetry axis.The rainfall in area along Huaihe River showed wavy distribution in east-west direction.The flood disaster loss index and disaster area of crops in Huaihe River basin of Anhui both increased as rainfall in Meiyu period.[Conclusion] The research provided theoretical basis for flood prevention,disaster reduction and agricultural flood-avoiding development in Huaihe River basin.展开更多
This research aims to understand more closely the damage to the lake environment and the factors that cause pollution in Lake Santa Maria are the first factor of increasing urbanization, the use of the land around the...This research aims to understand more closely the damage to the lake environment and the factors that cause pollution in Lake Santa Maria are the first factor of increasing urbanization, the use of the land around the lake as a place to live, the absence of maximum control from the local government this case, the Dili municipal authority. Types of solid waste consist of iron from car accidents, motorcycles, used building materials, plastic, used drink bottles and clothes, mosquito nets, food scraps from household waste, as well as old fishing nets from residents. In addition, household waste such as bath and bath, dishwashing, detergents, and waste from tempeh and tofu factories, including burnt oil from cars and motorcycles, are thrown into the lake. Municipal waste management is based on environmental standards to determine the quality of waste management in Dili Municipality. It is possible to identify the composition of waste and waste, as well as predict its environmental impact. Human (Anthropic) factors Domestic Liquid Waste, Domestic Solid Waste: Composed of organic and inorganic waste. Synthetic Waste, Disposal of Used Oil, Disposal of Domestic Animal Waste, Shallow Drains and Septic Tanks, Mountain Garbage, Garbage Thrown by Visitors, Natural Factors, Climate change, Prolonged drought, Low rainfall, El Niño and La Niña factors, Wind speed, Heat (high daily temperature pressure), Greater water evaporation, Dry wind. The occurrence of contamination necessarily implies an ecological imbalance. The impact introduced by residual compounds and waste that may be associated with the toxicity.展开更多
With the development of the time and the progress of economy,great changes have taken place in the environment.In recent years,it is common to see bad weather,such as hurricane,drought,lightning and so on.The emergenc...With the development of the time and the progress of economy,great changes have taken place in the environment.In recent years,it is common to see bad weather,such as hurricane,drought,lightning and so on.The emergence of these weather has the greatest impact on farmers and crops,especially the lightning weather,not only that,but also sometimes cause personal injury.In face of the frequent occurrence of bad weather in recent years and its harm and threat to China's agriculture,rural areas,personnel,etc.,the author makes a detailed study on the causes of rural lightning weather,analyzes the lightning protection measures in rural areas and their shortcomings,and summarizes the relevant improvement measures.展开更多
[Objective] The aim was to analyze the causes of low-temperature rain and snow disasters in 2008.[Method] Based on the basic meteorological observation data,a primary study was implemented about the severe cold air an...[Objective] The aim was to analyze the causes of low-temperature rain and snow disasters in 2008.[Method] Based on the basic meteorological observation data,a primary study was implemented about the severe cold air and frozen rain event.The importance of factors causing disaster,territory and human activity in the formation of low-temperature rain and snow disasters were expounded.[Result] The factors triggering the disasters were so strong that were rarely seen in previous (stronger than that in 1954);the specific terrain was beneficial to the occurrence of the frozen rain;the human being’s action amplified the impacts of disaster events while suffering it.Furthermore,a point of view to minimize the climate disaster damage like this severe frozen rain was proposed.Improvement of forecast capability and accuracy,implementation of the demonstration about climatic feasibility,and propagation to public about the natural disaster’s protection and mitigation and so on were functional aspects.[Conclusion] The study provided theoretical basis for the prediction and forecast of low-temperature rain and snow disasters.展开更多
Henan Province is not only one of the provinces with the most POpulation, but also one of the provinces with the most disabled people in China. The characteristics of the disabled People, the distribution law of six t...Henan Province is not only one of the provinces with the most POpulation, but also one of the provinces with the most disabled people in China. The characteristics of the disabled People, the distribution law of six typeS of the disabled, and the reason c展开更多
Natural disasters usually involve a phenomenon with consequences that exceed the response capabilities of local communities and have a significant impact on the region’s socioeconomic development. Droughts, floods, a...Natural disasters usually involve a phenomenon with consequences that exceed the response capabilities of local communities and have a significant impact on the region’s socioeconomic development. Droughts, floods, and hurricanes are all natural disasters that jeopardize the environment and the lives of Somalis. Severe floods have devastated the south and central parts of the country multiple times, destroying infrastructure and homes and killing many vulnerable people. Droughts in the south and central parts of the country, particularly in the Middle Shebelle region, have killed a number of children and mothers. It also had a negative influence on crops and cattle. Objective of this study is to know the recurrence of Natural Disasters in Jowhar, Middle Shabelle region, Somalia: The Causes and Impacts. The Somali people are completely aware of natural disasters such as droughts and floods, and they are self-sufficient in dealing with the consequences of these disasters. Furthermore, the Somali government has not fully created environmental laws to protect and conserve the environment, and the majority of laws, rules, acts, and regulations are not used or administered effectively. We also found that the Somali government is not yet financially prepared to deal with these crises, and that there are no strategic plans in the central government or even state administrations to prevent or at least control these disasters from causing extreme harm to the community and the environment.展开更多
Objective:To identify the influential factors of healthcare staff resilience in disasters.Methods:In this qualitative study,the influential factors of healthcare staff resilience in disasters were investigated through...Objective:To identify the influential factors of healthcare staff resilience in disasters.Methods:In this qualitative study,the influential factors of healthcare staff resilience in disasters were investigated through interviewing 20 experts.The interviews were conducted face-to-face,and MAXQDA software version 10 was used to organize the data and thematic analysis.Results:The participants included 5 medical emergency technicians,5 physicians,2 Red Crescent technicians,and 8 nurses.The main influential factors of healthcare providers’resilience were limited relief infrastructure,supportive empowerment,organizational capitals,and contradictory consequences.Other important factors were resource limitation,confusion and uncertainty,empowerment training,comprehensive support,human and value capital,social capital,physical capital,suffering,disability,calm,and excellence.Conclusion:Improving healthcare providers’resilience can be achieved by reducing uncertainty,providing the physical,economic,and human resources,strengthening motivation and comprehensive supports.It is suggested that disaster managers consider all identified dimensions to improve the resilience of healthcare providers to serve better in disasters.Moreover,researchers should study each dimension to provide profound knowledge regarding resilience in disasters.展开更多
BACKGROUND Low serum albumin levels are established predictors of adverse outcomes in various cardiovascular conditions.However,the role of serum albumin in mortality among elderly patients with chronic aortic regurgi...BACKGROUND Low serum albumin levels are established predictors of adverse outcomes in various cardiovascular conditions.However,the role of serum albumin in mortality among elderly patients with chronic aortic regurgitation(AR)has not been thoroughly investigated.This study aims to assess the relationship between serum albumin levels and mortality in this specific patient population.METHODS Our analysis included 873 elderly AR patients from the China Valvular Heart Disease study,with baseline serum albumin measured at enrollment.Mortality outcomes were monitored for two years post-enrollment,employing a Cox proportional hazards model with a two-piecewise Cox proportional hazards framework to investigate the nonlinear relationship between serum albumin levels and all-cause mortality.RESULTS During the 2-year follow-up period,we observed 63 all-cause deaths.The association between serum albumin levels and all-cause mortality displayed an approximating L-shaped curve,indicating a mortality threshold at 35 g/L.For serum albumin levels below 35 g/L,each 1 g/L decrease was associated with a 25%higher risk of all-cause mortality(HR=1.25,95%CI:1.07–1.45).In contrast,no significant change in mortality risk was observed when serum albumin levels were greater than or equal to 35 g/L.Moreover,when serum albumin is classified as hypoproteinemia(serum albumin<35 g/L),the higher risks of all-cause death were observed in hypoproteinemic patients(HR=2.93,95%CI:1.50–5.74).More importantly,the association between serum albumin and death was significantly stronger in overweight/obese patients(≥24 kg/m^(2)vs.<24 kg/m^(2),Pinteraction=0.006).CONCLUSIONS In elderly patients with AR,serum albumin levels showed an approximating L-shaped relationship with all-cause death,with thresholds of 35 g/L.Body mass index was significant effect modifiers of the association.These results suggest that serum albumin,as an inexpensive and readily available biochemical marker,may further improve the stratified risk of mortality in older AR patients.展开更多
The evacuation of people under threat is an effective disaster prevention and mitigation measure in response to flash floods and geological hazards,and it is also an essential element of pre-disaster planning.However,...The evacuation of people under threat is an effective disaster prevention and mitigation measure in response to flash floods and geological hazards,and it is also an essential element of pre-disaster planning.However,the effect of the interactions between perception factors on residents'willingness to evacuate is an urgent problem to be solved.Therefore,this paper introduces risk,stakeholder,and protective action perceptions from the protective action decision model as the main explanatory variables.These three core perceptions are subdivided into affective risk perception,cognitive risk perception,government perception,other-stakeholder perception,resourcerelated attributes,and hazard-related attributes.A questionnaire survey was conducted from June to July 2023 among residents of mountainous communities in nine villages in three towns in Sichuan Province,China.359 cross-sectional data were analyzed using structural equation modeling to explore the effects of six perception factors on evacuation intentions.The results of the study showed that:(1)affective risk perception,government perception,other-stakeholder perception,and hazard-related attributes all directly and positively influence residents'intentions to evacuate;(2)cognitive risk perception is mediated by stakeholder and protective action perceptions,which indirectly and positively affect residents'intentions to evacuate.Based on the hypothesized paths,strategies to improve residents'willingness to evacuate are discussed from the perspective of three core perceptions:strengthening disaster risk education,improving residents'cohesion,and building government credibility.The results of this study can provide theoretical support and practical suggestions for emergency management departments to formulate emergency evacuation strategies,which can aid decision-makers in better understanding residents'intentions to evacuate,optimizing evacuation information dissemination pathways,and strengthening disaster risk management capabilities.展开更多
This paper analyzed the severe drought that took place in the five provinces of Northern China in 1920.Study suggested that the severe damage caused by the drought was resulted from many reasons,such as certain specif...This paper analyzed the severe drought that took place in the five provinces of Northern China in 1920.Study suggested that the severe damage caused by the drought was resulted from many reasons,such as certain specific natural conditions,deterioration of ecological environment,malformations of the rural economy and turbulence of domestic politics.However,some new phenomena took shapes during this time disaster relief activity.展开更多
Landslide susceptibility maps(LSMs) play a vital role in assisting land use planning and risk mitigation. This study aims to optimize causative factors using logistic regression(LR) and an artificial neural network(AN...Landslide susceptibility maps(LSMs) play a vital role in assisting land use planning and risk mitigation. This study aims to optimize causative factors using logistic regression(LR) and an artificial neural network(ANN) to produce a LSM. The LSM is produced with 11 causative factors and then optimized using forward-stepwise LR(FSLR), ANN, and their combination(FSLR-ANN) until eight causative factors were found for each method. The ANN method produced superior validation results compared with LR. The ROC values for the training data set ranges between 0.8 and 0.9. On the other hand, validation with the percentage of landslide fall into LSM class high and very high, ANN method was higher(92.59%) than LR(82.12%). FSLR-ANN with nine causative factors gave the best validation results with respect to area under curve(AUC) values, and validation with the percentage of landslide fall into LSM class high and very high. In conclusion, ANN was found to be better than LR when producing LSMs. The best Optimization was combination of FSLR-ANN with nine causative factors and AUC success rate 0.847, predictive rate 0.844 and validation with landslide fall into high and very high class with 91.30%. It is an encouraging preliminary model towards a systematic introduction of FSLR-ANN model for optimization causative factors in landslide susceptibility assessment in the mountainous area of Ujung Loe Watershed.展开更多
Extreme meteorological disaster effects on grain production is mainly determined by the interaction between danger degree of hazard-induced factors and vulnerability degree of hazard-affected bodies. This paper treats...Extreme meteorological disaster effects on grain production is mainly determined by the interaction between danger degree of hazard-induced factors and vulnerability degree of hazard-affected bodies. This paper treats physical exposure, sensitivity of the response to the impact, and capabilities of disaster prevention and mitigation as a complex system for vulnerability degree of hazard-affected bodies, which included the external shocks and internal stability mechanism. Hazard-induced factors generate external shocks on grain production systems though exposure and sensitivity of hazard-affected body, and the result can be represented as affected area of grain. By quantile regression model, this paper depicts the quantitative relationship between hazard-induced factors of extreme meteorological disaster and the affected area in the tail of the distri- bution. Moreover, the model of production function have also been utilized to expound and prove the quantitative relationship between the affected area and final grain output under the internal stability mechanism of the agricultural natural resources endowment, the input factors of agricultural production, and the capacity of defending disaster. The empirical study of this paper finds that impact effects of drought disaster to grain production system presents the basic law of ＂diminishing marginal loss＂, namely, with the constant improvement of the grade of drought, marginal affected area produced by hazard-induced factors will be diminishing. Scenario simulation of extreme drought impact shows that by every 1% reduction in summer average rainfall, grain production of Jilin Province will fell 0.2549% and cut production of grain 14.69% eventually. In re- sponse to ensure China＇s grain security, the construction of the long-term mechanism of agricultural disaster prevention and mitigation, and the innovation of agricultural risk management tools should be also included in the agricultural policy agenda.展开更多
Low-resistivity oil layers are often missed in logging interpretation because of their resistivity close to or below the resistivity of nearby water layers. Typical low-resistivity oil layers have been found in the pa...Low-resistivity oil layers are often missed in logging interpretation because of their resistivity close to or below the resistivity of nearby water layers. Typical low-resistivity oil layers have been found in the past few years in the Putaohua reservoir of the Puao Oilfield in the south of the Daqing placanticline by detailed exploration. Based on a study of micro-geological causes of low-resistivity oil layers, the macro-geological controlling factors were analyzed through comprehensive research of regional depositional background, geological structure, and oil-water relations combined with core, water testing, well logging, and scanning electron microscopy data. The results showed that the formation and distribution of Putaohua low-resistivity oil layers in the Puao Oilfield were controlled by depositional environment, sedimentary facies, diagenesis, motive power of hydrocarbon accumulation, and acidity and alkalinity of reservoir liquid. The low-resistivity oil layers caused by high bound-water saturation were controlled by deposition and diagenesis, those caused by high free-water saturation were controlled by structural amplitude and motive power of hydrocarbon accumulation. Those caused by formation water with high salinity were controlled by the ancient saline water depositional environment and faulted structure and those caused by additional conductivity of shale were controlled by paleoclimate and acidity and alkalinity of reservoir liquid. Consideration of both micro-geological causes and macro-geological controlling factors is important in identifying low-resistivity oil layers.展开更多
Hazards in reservoirs and lakes arising from subaerial landslides causing impact waves(or ‘lake tsunamis’) are now well known, with several recent examples having been investigated in detail. The potential scale of ...Hazards in reservoirs and lakes arising from subaerial landslides causing impact waves(or ‘lake tsunamis’) are now well known, with several recent examples having been investigated in detail. The potential scale of such hazards was not widely known at the time of the Vaiont dam project in the 1950s and early 1960s, although a small wave triggered by a landslide at another new reservoir nearby in the Dolomites(northern Italy) drew the possible hazard to the attention of the Vaiont project’s managers. The Vaiont disaster in 1963 arose from a combination of disparate and seemingly unrelated factors and circumstances that led to an occurrence that could not have been imagined at that time. The ultimate cause was a very large landslide moving very rapidly into a reservoir and displacing the water. The resulting wave overtopped the dam to a height of around 175 m and around 2000 people were killed. This paper identifies and examines all of the issues surrounding the Vaiont dam and landslide in order to identify causal factors, contributory factors(including aggravating factors) and underlying factors. In doing so, it demonstrates that the disaster arose from the Vaiont dam project and cannot be attributed simply to the landslide. Underlying geological factors gave rise to the high speed of the landslide, which would have occurred anyway at some time. However, without the contributory factors that account for the presence of the reservoir, i.e. the choice of location for the project and management of the project with respect to a possible landslide hazard, there would have been no disaster. Indeed, the disaster could have been avoided if the reservoir could have been emptied pending further ground investigations. Understanding of this case provides many lessons for future dam projects in mountainous locations but also highlights an ongoing and perhaps under-appreciated risk from similar events involving other water bodies including geologically recent lakes formed behind natural landslide dams.展开更多
Haze pollution is a hot research topic at present,and it is of great significance to prevent and control haze pollution.In this paper,specific causes of haze pollution in China are analyzed by literature research and ...Haze pollution is a hot research topic at present,and it is of great significance to prevent and control haze pollution.In this paper,specific causes of haze pollution in China are analyzed by literature research and summary,and impacts of economic structure,energy structure and compound factors on haze pollution are explored.Finally,the prevention and control measures of haze pollution are summarized.展开更多
<strong>Background:</strong><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> Postpartum haemorrhage ...<strong>Background:</strong><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> Postpartum haemorrhage is one of the leading causes of maternal morbidity and mortality worldwide. It occurs predominantly in developing countries due to poorly developed infrastructures and lack of skilled birth attendants.</span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><b><span style="font-family:Verdana;">Objective:</span></b></span></span><span><span><b><span style="font-family:""> </span></b></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">To identify the prevalence, causes and risk factors of primary postpartum haemorrhage following vaginal deliveries in a referral hospital (Douala General Hospital-Cameroon).</span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><b><span style="font-family:Verdana;">Methods:</span></b></span></span><span><span><b><span style="font-family:""> </span></b></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;">This was a descriptive and analytical study carried in the Douala General Hospital (DGH) for which socio-demographic, clinical, obstetric and post-partum data were collected using a pre-tested questionnaire. Descriptive statistics, multivariate analysis and logistic regression allowed us to present and discuss our results, with a 95% confidence interval (CI) and </span><i><span style="font-family:Verdana;">p </span></i><span style="font-family:Verdana;">value <</span></span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">0.05.</span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><b><span style="font-family:Verdana;">Results:</span></b></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> The prevalence of Primary Postpartum Haemorrhage was 1.33%. Quantification of bleeding was reported in only 13.15% of cases. The main causes were: uterine atony (36.18%), placental retention (25.65%), cervical tears (12.50%), perineal tears (10.52%) and cervico-vaginal tears (08.52%). The risk factors were: age between 19</span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">-</span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">35 years aOR = 4.52;95% CI = 2.65</span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">-</span></span></span><span><span><span style="font-family:""> </span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;">7.98;</span><i><span style="font-family:Verdana;">p</span></i><span style="font-family:Verdana;"> = 0.021);unemployment (aOR = 4.74;95% CI = 2.91</span></span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">-</span></span></span><span><span><span style="font-family:""> </span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;">6.02;</span><i><span style="font-family:Verdana;">p</span></i><span style="font-family:Verdana;"> = 0.001);being multigravida (aOR = 9.21;95% CI = 6.43</span></span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">-</span></span></span><span><span><span style="font-family:""> </span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;">12.48;</span><i><span style="font-family:Verdana;">p</span></i><span style="font-family:Verdana;"> = 0.035);history of abortion (aOR = 5.11;95% CI = 2.05</span></span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">-</span></span></span><span><span><span style="font-family:""> </span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;">7.29;</span><i><span style="font-family:Verdana;">p</span></i><span style="font-family:Verdana;"> = 0.004);preterm delivery (aOR = 6.88;95% CI = 2.72</span></span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">-</span></span></span><span><span><span style="font-family:""> </span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;">9.06;</span><i><span style="font-family:Verdana;">p</span></i><span style="font-family:Verdana;"> = 0.002);duration of labour</span></span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">> 12 hours (aOR = 4.05;95% CI = 2.46</span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">-</span></span></span><span><span><span style="font-family:""> </span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;">7.98;</span><i><span style="font-family:Verdana;">p</span></i><span style="font-family:Verdana;"> = 0.003) and macrosomia (aOR = 3.27;95% CI = 1.03</span></span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">-</span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">5</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">.</span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;">68;</span><i><span style="font-family:Verdana;">p</span></i><span style="font-family:Verdana;"> = 0.041).</span></span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><b><span style="font-family:Verdana;">Conclusion:</span></b></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> Primary postpartum haemorrhage remains a poorly assessed obstetric complication in the maternity ward of the Douala General Hospital (DGH);Training staff on quantifying postpartum blood loss and monitoring the second and third stages of labour can help to better manage and reduce its occurrence.</span></span></span>展开更多
文摘Based on meteorological data of Zhumadian City in the past 56 years, the damage of flood-causing rainstorm to towns in Zhumadian City as well as its cataclysm form, influencing system, cataclysm characteristics and action mechanism were analyzed to discuss the characteristics and rules of damage caused by flood-causing rainstorm. Meanwhile, countermeasures against flood-causing rainstorm cataclysm in Zhumadian City were proposed to provide scientific references for early warning and monitoring of flood-causing rainstorm as well as flood control and disaster mitigation.
基金the National Key Research and Development Program of China(Grant No.2022YFF1302405)the Yunnan Province Key Research and Development Program(Grant No.202203AC100005)+1 种基金the National Natural Science Foundation of China(Grant No.42061005,42067033)Applied Basic Research Programs of Yunnan Province(Grant No.202101AT070110,202001BB050073).
文摘Flood disasters pose serious threats to human life and property worldwide.Exploring the spatial drivers of flood disasters on a macroscopic scale is of great significance for mitigating their impacts.This study proposes a comprehensive framework for integrating driving-factor optimization and interpretability,while considering spatial heterogeneity.In this framework,the Optimal Parameter-based Geographic Detector(OPGD),Recursive Feature Estimation(RFE),and Light Gradient Boosting Machine(LGBM)models were utilized to construct the OPGD–RFE–LGBM coupled model to identify the essential driving factors and simulate the spatial distribution of flood disasters.The SHapley Additive ExPlanation(SHAP)interpreter was employed to quantitatively explain the driving mechanisms behind the spatial distribution of flood disasters.Yunnan Province,a typical mountainous and plateau area in Southwest China,was selected to implement the proposed framework and conduct a case study.For this purpose,a flood disaster inventory of 7332 historical events was prepared,and 22 potential driving factors related to precipitation,surface environment,and human activity were initially selected.Results revealed that flood disasters in Yunnan Province exhibit high spatial heterogeneity,with geomorphic zoning accounting for 66.1%of the spatial variation in historical flood disasters.The OPGD–RFE–LGBM coupled model offers clear advantages over a single LGBM in identifying essential driving factors and quantitatively analyzing their impacts.Moreover,the simulation performance shows a slight improvement(a 6%average decrease in RMSE and an average increase of 1%in R2)even with reduced factor data.Factor explanatory analysis indicated that the combination of the essential driving factor sets varied across different subregions;nevertheless,precipitation-related factors,such as precipitation intensity index(SDII),wet days(R10MM),and 5-day maximum precipitation(RX5day),were the main driving factors controlling flood disasters.This study provides a quantitative analytical framework for the spatial drivers of flood disasters at large scales with significant heterogeneity,offering a reference for disaster management authorities in developing macro-strategies for disaster prevention.
基金supported by the Director Foundation of the Institute of Seismology,China Earthquake Administration(201056076,201116002)
文摘The seismic intensities, lithologic characteristics and terrain features from a 3000 km2-region near the epicenter of the Lushan earthquake are used to analyze earthquake-induced geological disaster. The preliminary results indicate that secondary effects of the earthquake will affect specific areas, including those with glutenite and carbonate bedrock, a seismic intensity of IX, slopes between 40° and 50°, elevations of less than 2500 m, slope change rates between 20° and 30°, slope curvatures from - 1 to -0.5 and 0. 5 to 1, and relief between 50 and 100 m. Regions with susceptibility indices greater than 0.71 are prone to landslides and collapses. The secondary features are mainly distributed on both sides of the ridges that extend from Baosheng to Shuangshi and from Baosheng to Longxing. Other features are scattered on both sides of the ridges that extend from Qishuping to Baosheng and from Masangping to Lingguan. The distribution of the earthquake-related features trends in the NE direction, and the area that was most affected by the Lushan earthquake covers approximately 52.4 km^2.
基金Supported by Special Project of Science Research in Public ServiceIndustry(Meteorology),China(GYHY200906019)
文摘[ Objective] The research aimed to study climatic characteristics of hail and dsk zoning of its disaster factor in Anhui Province. [Method] Based on the hail-day records from 82 weather stations in Anhui Province, Chinese Meteorologica/Disaster Dictionary （1951 to 2005） and The Yearbook of Meteorological Disaster in Anhui Province （2006 to 2009）, we discussed the climatic characteristic and dsk zoning of hail disaster in Anhui Province. [Result] The hail days exhibited significant interdecadal variability, and it had a significant negative correlation with annual mean minimum temperature. The hail usually occurred from March to August, most frequently in June but less in autumn and winter. It most likely took place from aftemoon to sunset. The spatial distribution showed that the hail occurred more in northeast of Huaibei, south of Dabie Mountain and some areas of Huangshan Mountain, but less in Jianghuai region. The index of hail intensity was defined by three factors, the diameter, duration and gust grade, and the percentile method was used to grade the intensity of the hail disaster. This work provided a possibility for quantitative assessment of the intensity of hail disaster. The results of hail disaster risk zoning in Anhui Province showed that high dsk zones were concentrated in northeast of Huaibei, and low risk zones were mainly in south of Huaihe River. Finally, vedfied by historic disaster, it showed that the results of risk zoning had a certain rationality and feasibility. Conclusion The research could provide reference basis for hail disaster defense and assessment.
基金Supported by Meteorological Open Research Fund of Huaihe River basin,China(HRM200805)Soft Science Research Plan of Ministry of Science and Technology,China(2007GXS3D087)
文摘[Objective] The research aimed to analyze temporal and spatial variation of strong precipitation caused flood and agricultural disaster loss in Huaihe River basin of Anhui Province during Meiyu period of 2007.[Method] On the basis of rainfalls of each station in Huaihe River basin of Anhui,rainfall data during Meiyu period of 2007 and flood disaster data in the same period,the temporal and spatial distribution characteristics of strong precipitation caused flood during Meiyu period of 2007 and its harm on agriculture were analyzed.The variation rule,distribution characteristics of strong precipitation during Meiyu period in Huaihe River basin of Anhui and its relationship with agricultural disaster loss were discussed.[Result] During Meiyu period of 2007 in Huaihe River basin of Anhui,the rainstorm was more,and the rainfall was large.The precipitation variation showed 'three-peak' trend.Rainfall in Huaihe River basin during Meiyu period of 2007 was greatly more than that homochronously in Yangtze River basin.The rain area over 400.0 mm during Meiyu period mainly located in Huaihe River basin,and the rain area over 600.0 mm mainly located from area along Huaihe River to central Huaibei.The rainfall during Meiyu period gradually decreased toward south and north by the north bank of Huaihe River as the symmetry axis.The rainfall in area along Huaihe River showed wavy distribution in east-west direction.The flood disaster loss index and disaster area of crops in Huaihe River basin of Anhui both increased as rainfall in Meiyu period.[Conclusion] The research provided theoretical basis for flood prevention,disaster reduction and agricultural flood-avoiding development in Huaihe River basin.
文摘This research aims to understand more closely the damage to the lake environment and the factors that cause pollution in Lake Santa Maria are the first factor of increasing urbanization, the use of the land around the lake as a place to live, the absence of maximum control from the local government this case, the Dili municipal authority. Types of solid waste consist of iron from car accidents, motorcycles, used building materials, plastic, used drink bottles and clothes, mosquito nets, food scraps from household waste, as well as old fishing nets from residents. In addition, household waste such as bath and bath, dishwashing, detergents, and waste from tempeh and tofu factories, including burnt oil from cars and motorcycles, are thrown into the lake. Municipal waste management is based on environmental standards to determine the quality of waste management in Dili Municipality. It is possible to identify the composition of waste and waste, as well as predict its environmental impact. Human (Anthropic) factors Domestic Liquid Waste, Domestic Solid Waste: Composed of organic and inorganic waste. Synthetic Waste, Disposal of Used Oil, Disposal of Domestic Animal Waste, Shallow Drains and Septic Tanks, Mountain Garbage, Garbage Thrown by Visitors, Natural Factors, Climate change, Prolonged drought, Low rainfall, El Niño and La Niña factors, Wind speed, Heat (high daily temperature pressure), Greater water evaporation, Dry wind. The occurrence of contamination necessarily implies an ecological imbalance. The impact introduced by residual compounds and waste that may be associated with the toxicity.
文摘With the development of the time and the progress of economy,great changes have taken place in the environment.In recent years,it is common to see bad weather,such as hurricane,drought,lightning and so on.The emergence of these weather has the greatest impact on farmers and crops,especially the lightning weather,not only that,but also sometimes cause personal injury.In face of the frequent occurrence of bad weather in recent years and its harm and threat to China's agriculture,rural areas,personnel,etc.,the author makes a detailed study on the causes of rural lightning weather,analyzes the lightning protection measures in rural areas and their shortcomings,and summarizes the relevant improvement measures.
基金Supported by Chinese Meteorological Bureau Business Program in 2009 " National Meteorological Disaster Risk Zone"Hunan Province Meteorological Bureau Key Science and Research Program (200801)
文摘[Objective] The aim was to analyze the causes of low-temperature rain and snow disasters in 2008.[Method] Based on the basic meteorological observation data,a primary study was implemented about the severe cold air and frozen rain event.The importance of factors causing disaster,territory and human activity in the formation of low-temperature rain and snow disasters were expounded.[Result] The factors triggering the disasters were so strong that were rarely seen in previous (stronger than that in 1954);the specific terrain was beneficial to the occurrence of the frozen rain;the human being’s action amplified the impacts of disaster events while suffering it.Furthermore,a point of view to minimize the climate disaster damage like this severe frozen rain was proposed.Improvement of forecast capability and accuracy,implementation of the demonstration about climatic feasibility,and propagation to public about the natural disaster’s protection and mitigation and so on were functional aspects.[Conclusion] The study provided theoretical basis for the prediction and forecast of low-temperature rain and snow disasters.
文摘Henan Province is not only one of the provinces with the most POpulation, but also one of the provinces with the most disabled people in China. The characteristics of the disabled People, the distribution law of six typeS of the disabled, and the reason c
文摘Natural disasters usually involve a phenomenon with consequences that exceed the response capabilities of local communities and have a significant impact on the region’s socioeconomic development. Droughts, floods, and hurricanes are all natural disasters that jeopardize the environment and the lives of Somalis. Severe floods have devastated the south and central parts of the country multiple times, destroying infrastructure and homes and killing many vulnerable people. Droughts in the south and central parts of the country, particularly in the Middle Shebelle region, have killed a number of children and mothers. It also had a negative influence on crops and cattle. Objective of this study is to know the recurrence of Natural Disasters in Jowhar, Middle Shabelle region, Somalia: The Causes and Impacts. The Somali people are completely aware of natural disasters such as droughts and floods, and they are self-sufficient in dealing with the consequences of these disasters. Furthermore, the Somali government has not fully created environmental laws to protect and conserve the environment, and the majority of laws, rules, acts, and regulations are not used or administered effectively. We also found that the Somali government is not yet financially prepared to deal with these crises, and that there are no strategic plans in the central government or even state administrations to prevent or at least control these disasters from causing extreme harm to the community and the environment.
基金financially supported by Iran University of Medical Sciences,Tehran,Iran.
文摘Objective:To identify the influential factors of healthcare staff resilience in disasters.Methods:In this qualitative study,the influential factors of healthcare staff resilience in disasters were investigated through interviewing 20 experts.The interviews were conducted face-to-face,and MAXQDA software version 10 was used to organize the data and thematic analysis.Results:The participants included 5 medical emergency technicians,5 physicians,2 Red Crescent technicians,and 8 nurses.The main influential factors of healthcare providers’resilience were limited relief infrastructure,supportive empowerment,organizational capitals,and contradictory consequences.Other important factors were resource limitation,confusion and uncertainty,empowerment training,comprehensive support,human and value capital,social capital,physical capital,suffering,disability,calm,and excellence.Conclusion:Improving healthcare providers’resilience can be achieved by reducing uncertainty,providing the physical,economic,and human resources,strengthening motivation and comprehensive supports.It is suggested that disaster managers consider all identified dimensions to improve the resilience of healthcare providers to serve better in disasters.Moreover,researchers should study each dimension to provide profound knowledge regarding resilience in disasters.
基金supported by the Chinese Academy of Medical Sciences Innovation Fund for Medical Sciences(2017-12M-3-002)the Central High Level Hospital Clinical Research Operating Expenses,China(Zero Balance 2022-GSP-GG-15)the Natural Science Foundation Project of the Inner Mongolia Autonomous Region of China(2022LHQN08003).
文摘BACKGROUND Low serum albumin levels are established predictors of adverse outcomes in various cardiovascular conditions.However,the role of serum albumin in mortality among elderly patients with chronic aortic regurgitation(AR)has not been thoroughly investigated.This study aims to assess the relationship between serum albumin levels and mortality in this specific patient population.METHODS Our analysis included 873 elderly AR patients from the China Valvular Heart Disease study,with baseline serum albumin measured at enrollment.Mortality outcomes were monitored for two years post-enrollment,employing a Cox proportional hazards model with a two-piecewise Cox proportional hazards framework to investigate the nonlinear relationship between serum albumin levels and all-cause mortality.RESULTS During the 2-year follow-up period,we observed 63 all-cause deaths.The association between serum albumin levels and all-cause mortality displayed an approximating L-shaped curve,indicating a mortality threshold at 35 g/L.For serum albumin levels below 35 g/L,each 1 g/L decrease was associated with a 25%higher risk of all-cause mortality(HR=1.25,95%CI:1.07–1.45).In contrast,no significant change in mortality risk was observed when serum albumin levels were greater than or equal to 35 g/L.Moreover,when serum albumin is classified as hypoproteinemia(serum albumin<35 g/L),the higher risks of all-cause death were observed in hypoproteinemic patients(HR=2.93,95%CI:1.50–5.74).More importantly,the association between serum albumin and death was significantly stronger in overweight/obese patients(≥24 kg/m^(2)vs.<24 kg/m^(2),Pinteraction=0.006).CONCLUSIONS In elderly patients with AR,serum albumin levels showed an approximating L-shaped relationship with all-cause death,with thresholds of 35 g/L.Body mass index was significant effect modifiers of the association.These results suggest that serum albumin,as an inexpensive and readily available biochemical marker,may further improve the stratified risk of mortality in older AR patients.
基金supported by the National Natural Science Foundation of China(U20A20111)the National key R&D Program(2022YFC3080100)。
文摘The evacuation of people under threat is an effective disaster prevention and mitigation measure in response to flash floods and geological hazards,and it is also an essential element of pre-disaster planning.However,the effect of the interactions between perception factors on residents'willingness to evacuate is an urgent problem to be solved.Therefore,this paper introduces risk,stakeholder,and protective action perceptions from the protective action decision model as the main explanatory variables.These three core perceptions are subdivided into affective risk perception,cognitive risk perception,government perception,other-stakeholder perception,resourcerelated attributes,and hazard-related attributes.A questionnaire survey was conducted from June to July 2023 among residents of mountainous communities in nine villages in three towns in Sichuan Province,China.359 cross-sectional data were analyzed using structural equation modeling to explore the effects of six perception factors on evacuation intentions.The results of the study showed that:(1)affective risk perception,government perception,other-stakeholder perception,and hazard-related attributes all directly and positively influence residents'intentions to evacuate;(2)cognitive risk perception is mediated by stakeholder and protective action perceptions,which indirectly and positively affect residents'intentions to evacuate.Based on the hypothesized paths,strategies to improve residents'willingness to evacuate are discussed from the perspective of three core perceptions:strengthening disaster risk education,improving residents'cohesion,and building government credibility.The results of this study can provide theoretical support and practical suggestions for emergency management departments to formulate emergency evacuation strategies,which can aid decision-makers in better understanding residents'intentions to evacuate,optimizing evacuation information dissemination pathways,and strengthening disaster risk management capabilities.
文摘This paper analyzed the severe drought that took place in the five provinces of Northern China in 1920.Study suggested that the severe damage caused by the drought was resulted from many reasons,such as certain specific natural conditions,deterioration of ecological environment,malformations of the rural economy and turbulence of domestic politics.However,some new phenomena took shapes during this time disaster relief activity.
文摘Landslide susceptibility maps(LSMs) play a vital role in assisting land use planning and risk mitigation. This study aims to optimize causative factors using logistic regression(LR) and an artificial neural network(ANN) to produce a LSM. The LSM is produced with 11 causative factors and then optimized using forward-stepwise LR(FSLR), ANN, and their combination(FSLR-ANN) until eight causative factors were found for each method. The ANN method produced superior validation results compared with LR. The ROC values for the training data set ranges between 0.8 and 0.9. On the other hand, validation with the percentage of landslide fall into LSM class high and very high, ANN method was higher(92.59%) than LR(82.12%). FSLR-ANN with nine causative factors gave the best validation results with respect to area under curve(AUC) values, and validation with the percentage of landslide fall into LSM class high and very high. In conclusion, ANN was found to be better than LR when producing LSMs. The best Optimization was combination of FSLR-ANN with nine causative factors and AUC success rate 0.847, predictive rate 0.844 and validation with landslide fall into high and very high class with 91.30%. It is an encouraging preliminary model towards a systematic introduction of FSLR-ANN model for optimization causative factors in landslide susceptibility assessment in the mountainous area of Ujung Loe Watershed.
基金funded by the National Natural Science Foundation of China (41201551)the Project of Science and Technology Innovation in Chinese Academy of Agricultural Science (CAAS-ASTIP-201X-AII-01)the Central Public-interest Scientific Institution Basal Research Fund in Agricultural Information Institute of CAAS (2015-J-16)
文摘Extreme meteorological disaster effects on grain production is mainly determined by the interaction between danger degree of hazard-induced factors and vulnerability degree of hazard-affected bodies. This paper treats physical exposure, sensitivity of the response to the impact, and capabilities of disaster prevention and mitigation as a complex system for vulnerability degree of hazard-affected bodies, which included the external shocks and internal stability mechanism. Hazard-induced factors generate external shocks on grain production systems though exposure and sensitivity of hazard-affected body, and the result can be represented as affected area of grain. By quantile regression model, this paper depicts the quantitative relationship between hazard-induced factors of extreme meteorological disaster and the affected area in the tail of the distri- bution. Moreover, the model of production function have also been utilized to expound and prove the quantitative relationship between the affected area and final grain output under the internal stability mechanism of the agricultural natural resources endowment, the input factors of agricultural production, and the capacity of defending disaster. The empirical study of this paper finds that impact effects of drought disaster to grain production system presents the basic law of ＂diminishing marginal loss＂, namely, with the constant improvement of the grade of drought, marginal affected area produced by hazard-induced factors will be diminishing. Scenario simulation of extreme drought impact shows that by every 1% reduction in summer average rainfall, grain production of Jilin Province will fell 0.2549% and cut production of grain 14.69% eventually. In re- sponse to ensure China＇s grain security, the construction of the long-term mechanism of agricultural disaster prevention and mitigation, and the innovation of agricultural risk management tools should be also included in the agricultural policy agenda.
基金supported by the National Natural ScienceFoundation Project(No.40173023)
文摘Low-resistivity oil layers are often missed in logging interpretation because of their resistivity close to or below the resistivity of nearby water layers. Typical low-resistivity oil layers have been found in the past few years in the Putaohua reservoir of the Puao Oilfield in the south of the Daqing placanticline by detailed exploration. Based on a study of micro-geological causes of low-resistivity oil layers, the macro-geological controlling factors were analyzed through comprehensive research of regional depositional background, geological structure, and oil-water relations combined with core, water testing, well logging, and scanning electron microscopy data. The results showed that the formation and distribution of Putaohua low-resistivity oil layers in the Puao Oilfield were controlled by depositional environment, sedimentary facies, diagenesis, motive power of hydrocarbon accumulation, and acidity and alkalinity of reservoir liquid. The low-resistivity oil layers caused by high bound-water saturation were controlled by deposition and diagenesis, those caused by high free-water saturation were controlled by structural amplitude and motive power of hydrocarbon accumulation. Those caused by formation water with high salinity were controlled by the ancient saline water depositional environment and faulted structure and those caused by additional conductivity of shale were controlled by paleoclimate and acidity and alkalinity of reservoir liquid. Consideration of both micro-geological causes and macro-geological controlling factors is important in identifying low-resistivity oil layers.
文摘Hazards in reservoirs and lakes arising from subaerial landslides causing impact waves(or ‘lake tsunamis’) are now well known, with several recent examples having been investigated in detail. The potential scale of such hazards was not widely known at the time of the Vaiont dam project in the 1950s and early 1960s, although a small wave triggered by a landslide at another new reservoir nearby in the Dolomites(northern Italy) drew the possible hazard to the attention of the Vaiont project’s managers. The Vaiont disaster in 1963 arose from a combination of disparate and seemingly unrelated factors and circumstances that led to an occurrence that could not have been imagined at that time. The ultimate cause was a very large landslide moving very rapidly into a reservoir and displacing the water. The resulting wave overtopped the dam to a height of around 175 m and around 2000 people were killed. This paper identifies and examines all of the issues surrounding the Vaiont dam and landslide in order to identify causal factors, contributory factors(including aggravating factors) and underlying factors. In doing so, it demonstrates that the disaster arose from the Vaiont dam project and cannot be attributed simply to the landslide. Underlying geological factors gave rise to the high speed of the landslide, which would have occurred anyway at some time. However, without the contributory factors that account for the presence of the reservoir, i.e. the choice of location for the project and management of the project with respect to a possible landslide hazard, there would have been no disaster. Indeed, the disaster could have been avoided if the reservoir could have been emptied pending further ground investigations. Understanding of this case provides many lessons for future dam projects in mountainous locations but also highlights an ongoing and perhaps under-appreciated risk from similar events involving other water bodies including geologically recent lakes formed behind natural landslide dams.
基金Supported by Jiaozuo Municipal Government Bidding Project(JZZ201911Z)Public Safety Project of Henan Polytechnic University(660113/016/004)Annual Project of Henan Polytechnic University(SKND2019-19)
文摘Haze pollution is a hot research topic at present,and it is of great significance to prevent and control haze pollution.In this paper,specific causes of haze pollution in China are analyzed by literature research and summary,and impacts of economic structure,energy structure and compound factors on haze pollution are explored.Finally,the prevention and control measures of haze pollution are summarized.
文摘<strong>Background:</strong><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> Postpartum haemorrhage is one of the leading causes of maternal morbidity and mortality worldwide. It occurs predominantly in developing countries due to poorly developed infrastructures and lack of skilled birth attendants.</span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><b><span style="font-family:Verdana;">Objective:</span></b></span></span><span><span><b><span style="font-family:""> </span></b></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">To identify the prevalence, causes and risk factors of primary postpartum haemorrhage following vaginal deliveries in a referral hospital (Douala General Hospital-Cameroon).</span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><b><span style="font-family:Verdana;">Methods:</span></b></span></span><span><span><b><span style="font-family:""> </span></b></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;">This was a descriptive and analytical study carried in the Douala General Hospital (DGH) for which socio-demographic, clinical, obstetric and post-partum data were collected using a pre-tested questionnaire. Descriptive statistics, multivariate analysis and logistic regression allowed us to present and discuss our results, with a 95% confidence interval (CI) and </span><i><span style="font-family:Verdana;">p </span></i><span style="font-family:Verdana;">value <</span></span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">0.05.</span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><b><span style="font-family:Verdana;">Results:</span></b></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> The prevalence of Primary Postpartum Haemorrhage was 1.33%. Quantification of bleeding was reported in only 13.15% of cases. The main causes were: uterine atony (36.18%), placental retention (25.65%), cervical tears (12.50%), perineal tears (10.52%) and cervico-vaginal tears (08.52%). The risk factors were: age between 19</span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">-</span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">35 years aOR = 4.52;95% CI = 2.65</span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">-</span></span></span><span><span><span style="font-family:""> </span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;">7.98;</span><i><span style="font-family:Verdana;">p</span></i><span style="font-family:Verdana;"> = 0.021);unemployment (aOR = 4.74;95% CI = 2.91</span></span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">-</span></span></span><span><span><span style="font-family:""> </span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;">6.02;</span><i><span style="font-family:Verdana;">p</span></i><span style="font-family:Verdana;"> = 0.001);being multigravida (aOR = 9.21;95% CI = 6.43</span></span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">-</span></span></span><span><span><span style="font-family:""> </span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;">12.48;</span><i><span style="font-family:Verdana;">p</span></i><span style="font-family:Verdana;"> = 0.035);history of abortion (aOR = 5.11;95% CI = 2.05</span></span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">-</span></span></span><span><span><span style="font-family:""> </span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;">7.29;</span><i><span style="font-family:Verdana;">p</span></i><span style="font-family:Verdana;"> = 0.004);preterm delivery (aOR = 6.88;95% CI = 2.72</span></span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">-</span></span></span><span><span><span style="font-family:""> </span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;">9.06;</span><i><span style="font-family:Verdana;">p</span></i><span style="font-family:Verdana;"> = 0.002);duration of labour</span></span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">> 12 hours (aOR = 4.05;95% CI = 2.46</span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">-</span></span></span><span><span><span style="font-family:""> </span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;">7.98;</span><i><span style="font-family:Verdana;">p</span></i><span style="font-family:Verdana;"> = 0.003) and macrosomia (aOR = 3.27;95% CI = 1.03</span></span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">-</span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">5</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">.</span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;">68;</span><i><span style="font-family:Verdana;">p</span></i><span style="font-family:Verdana;"> = 0.041).</span></span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><b><span style="font-family:Verdana;">Conclusion:</span></b></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> Primary postpartum haemorrhage remains a poorly assessed obstetric complication in the maternity ward of the Douala General Hospital (DGH);Training staff on quantifying postpartum blood loss and monitoring the second and third stages of labour can help to better manage and reduce its occurrence.</span></span></span>
