As a new mode for Chinese overseas investment and a growth pole for industrialization and urbanization of the host countries,the overseas economic and trade cooperation zone(OETCZ) or overseas free economic zone(OFEZ)...As a new mode for Chinese overseas investment and a growth pole for industrialization and urbanization of the host countries,the overseas economic and trade cooperation zone(OETCZ) or overseas free economic zone(OFEZ) of China plays an important role under the Belt and Road Initiative.With the rising attention on OETCZ,studies regarding OETCZ have also increased.However,there is a lack of studies reviewing this topic’s progress,challenges and future directions.This paper employs a systematic review to examine the literature on the OETCZ along the Belt and Road,based on domestic and overseas studies.The results show that domestic studies account for a large proportion of the collected literature,compared to overseas studies.Interdisciplinary research focus includes inductive case studies from a classification perspective,deductive studies based on cultural and institutional perspectives,trade network and bilateral trade relations based on the perspectives of international trade and regional economy,spatial planning studies from urban planning perspective,and overseas comments and earlier studies on Japan’s and Singapore’s overseas parks from the geopolitical and international political perspectives.Despite diverse research contents and dramatic progress,limitations exist in current OETCZ-related studies,including a lack of exploration of the mechanism,questions and concerns from overseas scholars,sustainable development and other problems.Future studies should broaden and deepen research insights,including the “overseas free economic zones(OFEZ)” as a general designation to cover all other types of OETCZs,studies on the primary conditions of host countries,exploration of the theoretical issues behind China’s OETCZ,comparative study of OETCZs such as management structures,profit models,environmental standards and legal systems as well as popular issues questioned internationally.展开更多
Based on remote sensing and GIS techniques, land use maps in 2000, 2005 and 2010 in China′s coastal zone were produced, and structural raster data of land use were further generated to calculate land use intensity co...Based on remote sensing and GIS techniques, land use maps in 2000, 2005 and 2010 in China′s coastal zone were produced, and structural raster data of land use were further generated to calculate land use intensity comprehensive index(LUICI) for analyzing land use spatial-temporal characteristics at 1 km scale. Results show that: 1) from the perspective of spatial patterns of landforms at a macro scale, there is a significant difference in land use intensity between the north and the south of China′s coastal zone. Hotspots of changes mainly concentrated in metropolitan areas, estuaries and coastal wetlands; 2) elevation is an important factor that controlling land use spatial patterns at local scale. Land use intensity is much higher within areas below the elevation of 400 m and it decreased significantly as the elevation increasing; 3) there is a significant land-ocean gradient for land use intensity, which is low in island and near-shore areas, but high in the regions that 4–30 km far away the coastline because of much intensive human activities; however, in recent decades land use intensity had been promoted significantly in low near-shore area due to extensive sea reclamations; 4) significant differences of land use intensity were also found among provincial administrative units. A rising trend of land use intensity was found in provincial-level administrative units from 2000 to 2010. To sum up, elevation, land-ocean gradient, socio-economic status and policy are all influencing factors to the spatial patterns and temporal variations of land use intensity in China′s coastal zone.展开更多
China's overseas industrial parks contribute to political and economic cooperation, cultural exchange between home and host countries. Current studies mainly discuss the effect of overseas industrial parks from th...China's overseas industrial parks contribute to political and economic cooperation, cultural exchange between home and host countries. Current studies mainly discuss the effect of overseas industrial parks from the perspective of institutional and cultural difference, multi-scale coupling, as well as key partnerships, while little attention has been paid to the comprehensive analysis of overseas industrial parks. Based on a theoretical framework, this paper explores the overall effect of China's overseas industrial parks from the geo-effects perspective by using field interviews and a case study approach. The research shows that:(1) the geo-effects reveal the over effect of overseas industrial parks from the multiple and complementary dimensions of geopolitics, geo-economics, geo-society and geo-culture;(2) the Cambodia Sihanoukville Special Economic Zone, as a flagship BRI project, has produced the prominent and positive geo-effects;(3) the institutional-economic-cultural-environmental adaptability of overseas industrial parks is becoming important. Overseas industrial parks must be rooted in the politics, economy, society, and culture of host country;embedded in local social networks;balance the rights and interests of all stakeholders;and form the community of interests, community of destiny, and community of responsibility with political mutual trust, economic integration, cultural inclusiveness, and social harmony. The paper not only deepens the understanding about the overall effect of overseas industrial parks, but also provides decision support and theoretical reference for government policy makers and the overseas investment of enterprises.展开更多
Increased human activities in China's coastal zone have resulted in the depletion of ecological land resources.Thus,conducting current and future multi-scenario simulation research on land use and land cover chang...Increased human activities in China's coastal zone have resulted in the depletion of ecological land resources.Thus,conducting current and future multi-scenario simulation research on land use and land cover change(LUCC)is crucial for guiding the healthy and sustainable development of coastal zones.System dynamic(SD)-future land use simulation(FLUS)model,a coupled simulation model,was developed to analyze land use dynamics in China's coastal zone.This model encompasses five scenarios,namely,SSP1-RCP2.6(A),SSP2-RCP4.5(B),SSP3-RCP4.5(C),SSP4-RCP4.5(D),and SSP5-RCP8.5(E).The SD model simulates land use demand on an annual basis up to the year 2100.Subsequently,the FLUS model determines the spatial distribution of land use for the near term(2035),medium term(2050),and long term(2100).Results reveal a slowing trend in land use changes in China's coastal zone from 2000–2020.Among these changes,the expansion rate of construction land was the highest and exhibited an annual decrease.By 2100,land use predictions exhibit high accuracy,and notable differences are observed in trends across scenarios.In summary,the expansion of production,living,and ecological spaces toward the sea remains prominent.Scenario A emphasizes reduced land resource dependence,benefiting ecological land protection.Scenario B witnesses an intensified expansion of artificial wetlands.Scenario C sees substantial land needs for living and production,while Scenario D shows coastal forest and grassland shrinkage.Lastly,in Scenario E,the conflict between humans and land intensifies.This study presents pertinent recommendations for the future development,utilization,and management of coastal areas in China.The research contributes valuable scientific support for informed,long-term strategic decision making within coastal regions.展开更多
Aiming at the requirements of structural steel in Gen-IV nuclear reactor, the high-chromium martensitic heat-resistant steels containing 10–12% chromium were developed. The toughness of heat-affected zones(HAZs) is o...Aiming at the requirements of structural steel in Gen-IV nuclear reactor, the high-chromium martensitic heat-resistant steels containing 10–12% chromium were developed. The toughness of heat-affected zones(HAZs) is one of the important factors for evaluating the weldability of steels. In this paper, the simulated HAZs were fabricated using tempered SIMP steels. The effects of microstructures on the impact toughness of materials were analyzed using Vickers hardness tester, optical microscope, transmission electron microscope. Experimental results demonstrated that the HAZs of weldment were poor in toughness, much lower than that of the base metal. However, after experiencing post-weld heat treatment, the toughness of the HAZs increased greatly. The toughness became better in terms of CG-HAZ, FG-HAZ and IC-HAZ for the two steels, regardless of as-welded or after PWHT. Compared with SIMP7 steel, chemical compositions, such as C, Si, Mn and Cr, were adjusted to a lower content;the toughness of base metal and simulated HAZs was better in the case of SIMP11. The conjunct roles of dislocation density and carbon contents retained in the martensite led to poor impact toughness of the aswelded HAZs, because dislocations and carbon atoms affected the inner stresses within lattices.展开更多
Fugitive emission from industrial sources may result in ozone formation and health risk,while the exact contribution of this source remains incompletely understood.In this study,emission characteristics,ozone formatio...Fugitive emission from industrial sources may result in ozone formation and health risk,while the exact contribution of this source remains incompletely understood.In this study,emission characteristics,ozone formation potential(OFP)and health risk of fugitive VOCs in7 representative industries were investigated.Chemical material industry was the dominant contributor to VOCs of fugitive emission in comparison with other industries.The OFP of VOCs from fugitive emission was in the range of 1.45×10^(3)-3.98×10^(5)μg/m^(3),with a higher value than that of organized emission in seven industries except for the coking industry and the chemical material industry,suggesting that fugitive VOCs should be taken into account while developing control strategies.Acetaldehyde,m,p-xylene,n-nonane,ethylene,vinyl chloridethe and other high OFP-contributing species were the major reactive species that should be targeted.Health risk assessment investigated non-cancer and cancer risks of fugitive VOCs in 7 industries were all above safe level(HR>1 and LCR>1×10^(-4)),posing remarkable health threats to human health.OVOCs were the main contributor to non-cancer risk,while halohydrocarbons and aromatics contributed most to cancer risks,posing remarkable health threat on human health.Our findings highlighted the contribution of fugitive VOCs on ozone formation and health risk was underestimated,indicating which should be considered in emission control strategies of industrial sources.展开更多
The meiofauna composition and trophic groups of the nematode communities have been studied at a sandy intertidal zone in Sishili Bay along the Yantai coast(Yellow Sea,China).Nematoda was dominant among the 11 groups o...The meiofauna composition and trophic groups of the nematode communities have been studied at a sandy intertidal zone in Sishili Bay along the Yantai coast(Yellow Sea,China).Nematoda was dominant among the 11 groups of meiofauna.The meiofaunal densities were low,ranging between 111±47 and 542±131 ind./10 cm^(2).Results obtained from the correlation analysis made it possible to determine several factors that influence species composition and distribution.Generally,sediment granulometry significantly affected the communities.The highest abundance was found in fine-grained sediments(318.77±126 ind./10 cm^(2))com-pared to coarse-grained sediments(175±82 ind./10 cm2).Nematodes were predominant in all studied sites.A total of 70 species be-longing to 52 genera and 18 families were identified in the study area.There was a significant difference in nematode abundance(ANOVA,F=2.38,P<0.05)between the three sites.Nematode communities were characterized by a high level of species diversity in sediments composed mainly of very-fine sands(>63μm),with dominant species belonging to the genus Bathylaimus,Ptycho-laimellus,Spirinia,and Sabatieria.The trophic groups were dominated by non-selective deposit feeders(40.7%)and epistrate feed-ers(41.29%).In contrast,the species composition in medium grain sands was characterized by a low species diversity index and a high Simpson dominance index.Nematode communities showed similar dominant species compositions belonging to a single genus Bathylaimus,Enoplolaimus,and Oncholaimus,and in terms of trophic structure-representatives of deposit feeders(46.15%),preda-tors,and omnivores(64.71%)prevailed.The divergence of meiofaunal community structures can be explained by abiotic factors such as sediment grain size,salinity,and organic carbon content.Specifically,sediment particle size can explain the diversity of nematodes at the level of in abundance,diversity indices,and trophic structure.The highest nematode density and diversity coincided with the highest percentage of very fine sands.展开更多
Objective: To explore the antibacterial activity of combined use of Shuanghuanglian and cefoperazone sulbactam sodium on resistant strains of Pseudomonas aeruginosa. Methods: The Pseudomonas aeruginosa strains which w...Objective: To explore the antibacterial activity of combined use of Shuanghuanglian and cefoperazone sulbactam sodium on resistant strains of Pseudomonas aeruginosa. Methods: The Pseudomonas aeruginosa strains which were sensitive and resistant to cefoperazone sulbactam sodium were selected to prepare different test bacterial solutions respectively;The experimental liquid of Shuanghuanglian and Cefoperazone Sulbactam Sodium were prepared separately and set as different test groups and control groups;The Drug Sensitivity Tests of Shuanghuanglian and cefoperazone sulbactam sodium at different concentration gradients which were used alone or used in combination were carried out for different strains with sensitivity and resistance, And use standard entry as a reference control. Result: The results of drug sensitivity test of Shuanghuanglian combined with Cefoperazone-Sulbactam sodium against the resistant strains of Pseudomonas aeruginosa were compared with the results of drug sensitivity test of the two separately used, and the difference was statistically significant (P 〈 0.05) [The drug sensitivity test results of Shuanghuanglian and cefoperazone sulbactam sodium to Pseudomonas aeruginosa resistant strains were statistically significant compared with the drug sensitivity test results of Shuanghuanglian and Cefoperazone Sulbactam Sodium used separately (P 〈 0.05)];There was a dependence between strains and concentration in the effect of the combination of the two drugs. Conclusion: The combination of Shuanghuanglian and cefoperazone sulbactam sodium has synergistic antibacterial or bactericidal effect on Pseudomonas aeruginosa resistant strains. .展开更多
The Bohai Sea is a low-lying semi-enclosed sea area that is linked to the Yellow Sea via the Bohai straits(mixed zone). Its of fshore seabed is shallow, which makes it vulnerable to serious marine meteorological disas...The Bohai Sea is a low-lying semi-enclosed sea area that is linked to the Yellow Sea via the Bohai straits(mixed zone). Its of fshore seabed is shallow, which makes it vulnerable to serious marine meteorological disasters associated with the northward passage of Pacific tropical cyclones. Analyses on data of remote sensing and buoy of the mixed zone of the Yellow and Bohai seas indicate that all the wind speed, significant wave height, and salinity(SAL) increased, sea surface temperature decreased, and wind energy density changed considerably during the passage of tropical cyclone Matmo on July 25, 2014. It was found that the SAL inversion layer in the mixed zone of the Yellow and Bohai Seas was caused by the tropical cyclone. Furthermore, it was found that the tropical cyclone transported the northern Yellow Sea cold water mass(NYSCWM) into the mixed zone of the Yellow and Bohai Seas. The NYSCWM has direct influence on both the aquaculture and the ecological environment of the region. Therefore, further research is needed to establish the mechanism behind the formation of the SAL inversion layer in the mixed zone, and to determine the influence of tropical cyclones on the NYSCWM.展开更多
Background: Inadequate human resources are a major constraint to improving global health. The health sector is characterized by a high turnover coupled with internal as well as external brain drain but there is little...Background: Inadequate human resources are a major constraint to improving global health. The health sector is characterized by a high turnover coupled with internal as well as external brain drain but there is little information on intention to leave among health professionals in public health centers of Jimma Zone, Oromia Regional State. The aim of this study is to assess intention to leave and associated factors among health professionals in public health centers of Jimma Zone, southwest Ethiopia. Methods: A cross-sectional quantitative and qualitative study was conducted on seven randomly selected woredas (districts) which have 53 public health centers. All health professionals in sampled district public health centers were included (n = 505). Factor analysis was employed for all Likert scale instruments to extract factor(s) representing each of the scales using SPSS version 16.0. The qualitative data was analyzed by thematic analysis methods. Ethical approval was obtained from Jimma University. Results: Four hundred fifty five (90.1%) health professionals participated in the study;out of this, 290 (63.7%) had intention to leave. Among variables, job satisfaction (Beta = -0.298, (95% CI, -0.568 to -0.029), working environment (Beta = -0.612, (95% CI, -0.955 to -0.270), and organizational management (Beta = -0.552, (95% CI, 0.289 to 0.815) had statistically significant association with intention to leave among health professionals in public health centers of Jimma Zone. Conclusions: The overall intention to leave among health professionals was high. Level of job satisfaction, working environment, work pressure, and organizational management had statistically significant association with intention to leave. Thus, responsible bodies should aggressively work on the concerns identified, like, improvements in salary, promotion in terms of training/educational opportunity, improving working environment, and transfer of health professionals, and improvement of the leadership skills of managers.展开更多
This study investigates the relationship between demographic characteristics （company type, company ownership, company operating years, and sector） and supply logistics characteristics （source of supplies, average ...This study investigates the relationship between demographic characteristics （company type, company ownership, company operating years, and sector） and supply logistics characteristics （source of supplies, average number of suppliers for their products, replenishment frequency for their orders, and relationship with their suppliers） of companies that are operating in Mersin Free Zone along with their supplier selection criteria based on the 36 companies selected through convenience sampling. The finding implies that the relationships of company type---replenishment frequency, company type---relationship among suppliers, and company ownership---source of supplies are significant at the 95% confidence level. Besides, the most significant three supplier selection criteria are found to be quality, price, and delivery time respectively, while the least important three ones appear to be nationality （foreign/domestic） and the reputation of the supplier respectively.展开更多
Since the 18th National Congress of the Communist Party of China held in 2012,the construction of pilot free trade zone has emerged as a strategically important approach for China’s reform and opening up efforts.Thes...Since the 18th National Congress of the Communist Party of China held in 2012,the construction of pilot free trade zone has emerged as a strategically important approach for China’s reform and opening up efforts.These zones exemplify China’s proactive and open strategy,serving as a key driver for promoting high-quality development.In September 2013,China launched its first pilot free trade zone,China(Shanghai)Pilot Free Trade Zone.Over the past decade,21 additional pilot free trade zones have been established across the country.This expansion has created a comprehensive reform and opening up innovation agenda that spans the eastern,western,southern,northern,and central regions,while integrating coastal,inland,and border areas.展开更多
From April 2008 to November 2009, the nitrogen （N） cycle of plant-soil system in seepweed （Suaeda salsa） wetland in the intertidal zone of the Huanghe （Yellow） River estuary was studied. Results showed that soil...From April 2008 to November 2009, the nitrogen （N） cycle of plant-soil system in seepweed （Suaeda salsa） wetland in the intertidal zone of the Huanghe （Yellow） River estuary was studied. Results showed that soil N had sig- nificant seasonal fluctuations and vertical distribution, and the net N mineralization rates in topsoil were significantly different in growing season （p 〈 0.01）. The N/P ratio （9.87 ±1.23） of S. salsa was less than 14, indicating that plant growth was limited by N. The N accumulated in S. salsa litter at all times during decomposition, which was ascribed to the N immobilization by microbes from the environment. Soil organic N was the main N stock of plant-soil system, accounting for 97.35% of the total N stock. The N absorption and utilization coefficients of S. salsa were very low （0.0145 and 0.3844, respectively）, while the N cycle coefficient was high （0.7108）. The results of the N turnovers among compartments of S. salsa wetland showed that the N uptake amount of aboveground part and root were 7.764 g/m2and 4.332 g/m2, respectively. The N translocation amounts from aboveground part to root and from root to soil were 3.881 g/m2 and 0.626 g/m2, respectively. The N translocation amount from aboveground living body to litter was 3.883 g/m2, the annual N return amount from litter to soil was more than 0.125（-） g/m2 （minus represented immobili- zation）, and the net N mineralization amount in topsoil （0-15 cm） in growing season was 1.190 g/m2. The assessment of N biological cycle status orS. salsa wetland indicated that N was a very important limiting factor and the ecosystem was situated in unstable and vulnerable status. The S. salsa was seemingly well adapted to the low-nutrient status and vulnerable habitat, and the N quantitative relationships determined in the compartment model might provide scientific base for us to reveal the special adaptive strategy orS. salsa to the vulnerable habitat in the following studies.展开更多
The opening of the Panama Canal in 1913 transformed ocean-shipping and the availability of internationally-traded goods, shortened travel time between the Pacific and Atlantic oceans, increased ship tonnage, and spark...The opening of the Panama Canal in 1913 transformed ocean-shipping and the availability of internationally-traded goods, shortened travel time between the Pacific and Atlantic oceans, increased ship tonnage, and sparked the growth of port authorities on both the Atlantic and Pacific coasts of the Panama Canal. Historically, the United States was number one and China was number two in tons of cargo that pass through the canal annually in the high stakes game of import and export markets. Prior to the construction of the Panama Canal, the most efficient way to cross the 82-kilometer isthmus, between the Port of Panama City on the Pacific and the Port of Colon on the Atlantic, was by mule trails through tropical forests and river transportation. Since the construction of the Panama Canal through tropical forests in the 1910s, pesticides have been essential for managing mosquitoes as well as controlling wetland vegetation that blocked lakes, rivers and the canal. The pri<span>mary objective of this research study is to document the long-term environmental impacts of pesticide and herbicide use in the Panama Canal Zone. Many of these chemicals, including 2, 4,-D, 2, 4, 5-T and DDT, have a long half-life under water and some, like arsenic (As), have no half-life. Pesticides </span>and chemicals flowed into Lake Gatun via surface runoff either in solution or attached to the sediment during the rainy season. The by-product 2,3,7,8-tetrachlorodibenzo-<i>p</i>-dioxin (TCDD) is an unanticipated contaminant created during the manufacture of the herbicide 2,4,5-T. TCDD can bio-accumulate in fish and birds and enter into the human food supply. The extent of the current chemical and pesticide contamination on former U.S. military base grounds and in Lake Gatun is unknown. Systematic soil sampling of current and former military bases, chemical disposal sites and Lake Gatun or the Panama Canal sediments is needed to determine if mitigation is necessary.展开更多
Temperature variation and gas generation at diferent depths and positions in the coal combustion process were studied to determine the propagation and evolution of high temperature regions in the process of coal spont...Temperature variation and gas generation at diferent depths and positions in the coal combustion process were studied to determine the propagation and evolution of high temperature regions in the process of coal spontaneous combustion.This study selected coal samples from Mengcun,Shaanxi Province,People’s Republic of China,and developed a semi-enclosed experimental system(furnace)for simulating coal combustion.The thermal mass loss of coal samples under various heating rates(5,10,and 15℃/min)was analyzed through thermogravimetric analysis,and the dynamic characteristics of the coal samples were analyzed;the reliability of the semi-enclosed experimental system was verifed through the equal proportional method of fuzzy response.The results reveal that the high-temperature zone is distributed nonlinearly from the middle to the front end of the furnace,and the temperatures of points in this zone decreased gradually as the layer depth increased.The apparent activation energy of the coal samples during combustion frst increased and then decreased as the conversion degree increased.Furthermore,the proportion of mass loss and the mass loss rate in the coal samples observed in the thermogravimetric experiment is consistent with that observed in the frst and second stages of the experiment conducted using the semi-enclosed system.The research fndings can provide a theoretical basis for the prevention and control of hightemperature zones in coal combustion.展开更多
Geographical design of riparian buffers with long-term vegetation cover for environmental restoration in agricultural watersheds needs to assess how much farmland is located in the buffers of a concerned watershed. Tr...Geographical design of riparian buffers with long-term vegetation cover for environmental restoration in agricultural watersheds needs to assess how much farmland is located in the buffers of a concerned watershed. Traditionally, this assessment was done by field surveying and manual mapping, which was a time-consuming and costly process for a large region. In this paper, remote sensing （RS） and geographical information system （GIS） as cost-effective techniques were used to develop a catchments-based approach for identifying critical sites of agricultural riparian buffer restoration. The method was explained through a case study of watershed with ll catchments and results showed that only four of the catchments were eligible in terms of higher priority for riparian buffer restoration. This research has methodological contributions to the spatial assessment of farming intensities in catchments-based riparian buffers across a watershed and to the geographical designs of variable buffering scenarios within catchments. The former makes the catchments-based management strategy possible, and the latter provides alternative restoration scenarios to meet different management purposes, both of which have direct implementations to the environmental restoration of riparian buffers in the real world. This study, thus, highlights the great potential of RS and GIS applications to the planning and management of riparian buffer restoration in agricultural watersheds.展开更多
The Moroccan territory is often exposed to brutal and destructive floods. The latter is triggered by intense rains and sudden duration (rain showers, thunderstorms). The human and material damage caused by these flood...The Moroccan territory is often exposed to brutal and destructive floods. The latter is triggered by intense rains and sudden duration (rain showers, thunderstorms). The human and material damage caused by these floods has always been very high. The violence of the flood (1000 m<sup>3</sup>/s) of Oued Ourika on Aug 17, 1995, killed 730 people. The material damage caused by torrential rain only for the years 2008 and 2009 on the road network (roads and civil engineering works) represents more than 2.9 billion dirhams. The development of flood protection studies requires the values of the instantaneous frequency flow of a certain probability and the corresponding flood hydrogram, generally, these values are not available in the watersheds studied. The objective of this study is to propose for the Moroccan territory a method of calculating flood flows and hydrographs of floods for stream and wadis ungauged for the benefit of engineers and planners for possible studies of flood protection. The proposed method is based on the delimitation of homogeneous regions of Moroccan territory (three homogeneous regions). The frequency analysis carried out for these three zones made it possible to identify the climatic parameters necessary to calculate the flood index and consequently the frequency floods. The proposed Galton type flood hydrograph includes three parameters namely the rise time, the shape parameter and the flood index. These latter parameters are easily calculated by the formulas proposed.展开更多
Lamb morbidity and mortality cause significant loss in a smallholder production system. A longitudinal prospectivesurvey was conducted on 408 randomly selected farmers located in six purposefully selected kebeles in G...Lamb morbidity and mortality cause significant loss in a smallholder production system. A longitudinal prospectivesurvey was conducted on 408 randomly selected farmers located in six purposefully selected kebeles in Gewataworeda from June 2020 to July 2021 to determine the incidence of morbidity and mortality in lambs and to identifyrisk factors. For this purpose, 408 lambs from the Gewata district’s mixed crop-livestock production system wereexamined every day from birth to three months of age. The data was analyzed using the Kaplan-Meier (K-M) method,the log-rank test, and Cox proportional hazards regression. Results showed that the cumulative incidence of allcauseof morbidity and mortality at the end of three month was 12.86% (95% CI: 10.26–16.13%), and 6.86% (95% CI:5.03–9.35%), respectively. Diarrhea was the leading cause of morbidity and mortality, accounting for 49.33 and 50%morbidity and mortality, respectively. Pneumonia was the second most frequent cause of morbidity and death. In theK-M hazard analysis, the greatest risk of lamb morbidity and mortality was observed during the first month of life, andthen the risk decreased significantly as the lamb grew. Of the 17 potential risk factors studied, the multivariable Coxproportional hazards regression model showed that lamb sex, birth weight, umbilical care, time and method of colostrumfeeding were the five predictors that were significantly associated with a higher risk of morbidity, whereas birthweight, lambing difficulty, dams’ parity, method and time of colostrum feeding were the five predictors that weresignificantly associated with a higher risk of mortality. Moreover, a higher risk of morbidity was observed in lambswith methods of colostrum feeding after birth (HR = 3.158;p = 0.000) and with variations in birth weight (HR = 1.418;p = 0.003). Similarly, the mortality risk was 4.926 (p = 0.047), 4.023 (p = 0.012), and 3.206 (p = 0.000) times higher inlambs with lambing difficulties, at the time of colostrum feeding, and by the method of colostrum feeding, respectively.According to this research, lamb morbidity and mortality rates in the study area are significantly high whichhas a great impact on the replacement stock and production. Hence, awareness should be created among farmersconcerning improved lamb management practices.展开更多
Peatlands represent one of the most important economic resources and abandoned peatlands after mining can be considered as ecological resources by re-vegetation restoration or management. However, some environmental p...Peatlands represent one of the most important economic resources and abandoned peatlands after mining can be considered as ecological resources by re-vegetation restoration or management. However, some environmental problems like particles from peatlands and their effects in the water system have to be characterized. Since centuries, artificial drainage has been a current practice for the mining of peatlands. Mainly mined for horticultural purpose, New Brunswick＇s peatlands--predominantly located in the eastern of the province--cover about 140,000 ha. At the downstream end of the drainage system, the water from peatlands flow into sedimentation basins. Drainage waters are often laden with solid particles. Once they have flowed through the ponds to allow sediment settling, the water is released into the water system. This paper describes the spatio-temporal evolution of suspended solids from 12 New Brunswick drained peatlands. The studied sites were characterized by some heterogeneity in the concentration of suspended solids. This study also provides knowledge on the suspended solids amount that can be released by drained peatlands, and it proposes a function to estimate the concentration of suspended solids by using climate variables; and identifies some potential ecological risks.展开更多
Background: Disclosure of HIV sero status is among varies HIV prevention strategy to prevent the spread of HIV. It is the base for accessing care and treatment programs, attains psycho-social support and reduces stigm...Background: Disclosure of HIV sero status is among varies HIV prevention strategy to prevent the spread of HIV. It is the base for accessing care and treatment programs, attains psycho-social support and reduces stigma, adheres to treatment and promotes safer health behavior particularly for couples. Objective: To assess HIV sero status disclosure to sexual partner and associated factors among HIV positive adult patient in Bale Zone hospitals. Method: A cross-sectional study design was conducted among 411 adult HIV positive clients who were selected by using systematic random sampling methods from Bale Zone Hospitals. Data were collected by using pre-tested questionnaire after verbal consent obtained from participants by trained nurse. Multiple logistic regression analysis was done by using SPSS version 20 and P-value of less than 0.05 was taken to declare statistical significance. Result: HIV sero status disclosure to sexual partners was 52.6%. Residence (AOR = 1.62;95% CI, 1.0, 2.60), receiving pre-test counselling related disclosure (AOR = 6.25;95% CI, 3.45, 11.33) and knowledge of partner’s HIV sero status (P-Value = 0.001) were significantly associated with HIV sero status disclosure. Fear of stigma and violence by sexual partner were the main reasons suggested for not disclosing HIV sero-status. Conclusion: The level of HIV sero-status disclosure to sexual partner was low. Disclosure of HIV sero status to sexual partner was significantly associated with clients’ place of residence, receiving pre-test counselling about disclosure and Knowledge of partners HIV sero status.展开更多
基金National Natural Science Foundation of China,No.41971161Tianjin Normal University Interdisciplinary Integration Innovation Team Project,No.135205RH08The Fundamental Research Funds for the Central Universities,No.63232160。
文摘As a new mode for Chinese overseas investment and a growth pole for industrialization and urbanization of the host countries,the overseas economic and trade cooperation zone(OETCZ) or overseas free economic zone(OFEZ) of China plays an important role under the Belt and Road Initiative.With the rising attention on OETCZ,studies regarding OETCZ have also increased.However,there is a lack of studies reviewing this topic’s progress,challenges and future directions.This paper employs a systematic review to examine the literature on the OETCZ along the Belt and Road,based on domestic and overseas studies.The results show that domestic studies account for a large proportion of the collected literature,compared to overseas studies.Interdisciplinary research focus includes inductive case studies from a classification perspective,deductive studies based on cultural and institutional perspectives,trade network and bilateral trade relations based on the perspectives of international trade and regional economy,spatial planning studies from urban planning perspective,and overseas comments and earlier studies on Japan’s and Singapore’s overseas parks from the geopolitical and international political perspectives.Despite diverse research contents and dramatic progress,limitations exist in current OETCZ-related studies,including a lack of exploration of the mechanism,questions and concerns from overseas scholars,sustainable development and other problems.Future studies should broaden and deepen research insights,including the “overseas free economic zones(OFEZ)” as a general designation to cover all other types of OETCZs,studies on the primary conditions of host countries,exploration of the theoretical issues behind China’s OETCZ,comparative study of OETCZs such as management structures,profit models,environmental standards and legal systems as well as popular issues questioned internationally.
基金Under the auspices of Strategic Priority Research Program of Chinese Academy of Sciences(No.XDA05130703)Knowledge Innovation Program of Chinese Academy of Sciences(No.KZCX2-YW-224)2020-Planning Project of Yantai Institute of Coastal Zone Research of Chinese Academy of Sciences(No.Y254021031-6)
文摘Based on remote sensing and GIS techniques, land use maps in 2000, 2005 and 2010 in China′s coastal zone were produced, and structural raster data of land use were further generated to calculate land use intensity comprehensive index(LUICI) for analyzing land use spatial-temporal characteristics at 1 km scale. Results show that: 1) from the perspective of spatial patterns of landforms at a macro scale, there is a significant difference in land use intensity between the north and the south of China′s coastal zone. Hotspots of changes mainly concentrated in metropolitan areas, estuaries and coastal wetlands; 2) elevation is an important factor that controlling land use spatial patterns at local scale. Land use intensity is much higher within areas below the elevation of 400 m and it decreased significantly as the elevation increasing; 3) there is a significant land-ocean gradient for land use intensity, which is low in island and near-shore areas, but high in the regions that 4–30 km far away the coastline because of much intensive human activities; however, in recent decades land use intensity had been promoted significantly in low near-shore area due to extensive sea reclamations; 4) significant differences of land use intensity were also found among provincial administrative units. A rising trend of land use intensity was found in provincial-level administrative units from 2000 to 2010. To sum up, elevation, land-ocean gradient, socio-economic status and policy are all influencing factors to the spatial patterns and temporal variations of land use intensity in China′s coastal zone.
基金Tianjin Normal University Doctoral Fund,No.52XB1901National Natural Science Foundation of China,No.41701133, No.41971161+1 种基金Major Program of National Social Science Foundation of China,No.20&ZD138Tianjin Normal University Interdisciplinary Integration Innovation Team Project,No.135205RH08。
文摘China's overseas industrial parks contribute to political and economic cooperation, cultural exchange between home and host countries. Current studies mainly discuss the effect of overseas industrial parks from the perspective of institutional and cultural difference, multi-scale coupling, as well as key partnerships, while little attention has been paid to the comprehensive analysis of overseas industrial parks. Based on a theoretical framework, this paper explores the overall effect of China's overseas industrial parks from the geo-effects perspective by using field interviews and a case study approach. The research shows that:(1) the geo-effects reveal the over effect of overseas industrial parks from the multiple and complementary dimensions of geopolitics, geo-economics, geo-society and geo-culture;(2) the Cambodia Sihanoukville Special Economic Zone, as a flagship BRI project, has produced the prominent and positive geo-effects;(3) the institutional-economic-cultural-environmental adaptability of overseas industrial parks is becoming important. Overseas industrial parks must be rooted in the politics, economy, society, and culture of host country;embedded in local social networks;balance the rights and interests of all stakeholders;and form the community of interests, community of destiny, and community of responsibility with political mutual trust, economic integration, cultural inclusiveness, and social harmony. The paper not only deepens the understanding about the overall effect of overseas industrial parks, but also provides decision support and theoretical reference for government policy makers and the overseas investment of enterprises.
基金Under the auspices of National Natural Science Foundation of China (No.42176221,41901133)Strategic Priority Research Program of the Chinese Academy of Sciences (No.XDA19060205)Seed project of Yantai Institute of Coastal Zone Research,Chinese Academy of Sciences (No.YIC-E3518907)。
文摘Increased human activities in China's coastal zone have resulted in the depletion of ecological land resources.Thus,conducting current and future multi-scenario simulation research on land use and land cover change(LUCC)is crucial for guiding the healthy and sustainable development of coastal zones.System dynamic(SD)-future land use simulation(FLUS)model,a coupled simulation model,was developed to analyze land use dynamics in China's coastal zone.This model encompasses five scenarios,namely,SSP1-RCP2.6(A),SSP2-RCP4.5(B),SSP3-RCP4.5(C),SSP4-RCP4.5(D),and SSP5-RCP8.5(E).The SD model simulates land use demand on an annual basis up to the year 2100.Subsequently,the FLUS model determines the spatial distribution of land use for the near term(2035),medium term(2050),and long term(2100).Results reveal a slowing trend in land use changes in China's coastal zone from 2000–2020.Among these changes,the expansion rate of construction land was the highest and exhibited an annual decrease.By 2100,land use predictions exhibit high accuracy,and notable differences are observed in trends across scenarios.In summary,the expansion of production,living,and ecological spaces toward the sea remains prominent.Scenario A emphasizes reduced land resource dependence,benefiting ecological land protection.Scenario B witnesses an intensified expansion of artificial wetlands.Scenario C sees substantial land needs for living and production,while Scenario D shows coastal forest and grassland shrinkage.Lastly,in Scenario E,the conflict between humans and land intensifies.This study presents pertinent recommendations for the future development,utilization,and management of coastal areas in China.The research contributes valuable scientific support for informed,long-term strategic decision making within coastal regions.
文摘Aiming at the requirements of structural steel in Gen-IV nuclear reactor, the high-chromium martensitic heat-resistant steels containing 10–12% chromium were developed. The toughness of heat-affected zones(HAZs) is one of the important factors for evaluating the weldability of steels. In this paper, the simulated HAZs were fabricated using tempered SIMP steels. The effects of microstructures on the impact toughness of materials were analyzed using Vickers hardness tester, optical microscope, transmission electron microscope. Experimental results demonstrated that the HAZs of weldment were poor in toughness, much lower than that of the base metal. However, after experiencing post-weld heat treatment, the toughness of the HAZs increased greatly. The toughness became better in terms of CG-HAZ, FG-HAZ and IC-HAZ for the two steels, regardless of as-welded or after PWHT. Compared with SIMP7 steel, chemical compositions, such as C, Si, Mn and Cr, were adjusted to a lower content;the toughness of base metal and simulated HAZs was better in the case of SIMP11. The conjunct roles of dislocation density and carbon contents retained in the martensite led to poor impact toughness of the aswelded HAZs, because dislocations and carbon atoms affected the inner stresses within lattices.
基金supported by the National Natural Science Foundation of China (No.42177420)。
文摘Fugitive emission from industrial sources may result in ozone formation and health risk,while the exact contribution of this source remains incompletely understood.In this study,emission characteristics,ozone formation potential(OFP)and health risk of fugitive VOCs in7 representative industries were investigated.Chemical material industry was the dominant contributor to VOCs of fugitive emission in comparison with other industries.The OFP of VOCs from fugitive emission was in the range of 1.45×10^(3)-3.98×10^(5)μg/m^(3),with a higher value than that of organized emission in seven industries except for the coking industry and the chemical material industry,suggesting that fugitive VOCs should be taken into account while developing control strategies.Acetaldehyde,m,p-xylene,n-nonane,ethylene,vinyl chloridethe and other high OFP-contributing species were the major reactive species that should be targeted.Health risk assessment investigated non-cancer and cancer risks of fugitive VOCs in 7 industries were all above safe level(HR>1 and LCR>1×10^(-4)),posing remarkable health threats to human health.OVOCs were the main contributor to non-cancer risk,while halohydrocarbons and aromatics contributed most to cancer risks,posing remarkable health threat on human health.Our findings highlighted the contribution of fugitive VOCs on ozone formation and health risk was underestimated,indicating which should be considered in emission control strategies of industrial sources.
文摘The meiofauna composition and trophic groups of the nematode communities have been studied at a sandy intertidal zone in Sishili Bay along the Yantai coast(Yellow Sea,China).Nematoda was dominant among the 11 groups of meiofauna.The meiofaunal densities were low,ranging between 111±47 and 542±131 ind./10 cm^(2).Results obtained from the correlation analysis made it possible to determine several factors that influence species composition and distribution.Generally,sediment granulometry significantly affected the communities.The highest abundance was found in fine-grained sediments(318.77±126 ind./10 cm^(2))com-pared to coarse-grained sediments(175±82 ind./10 cm2).Nematodes were predominant in all studied sites.A total of 70 species be-longing to 52 genera and 18 families were identified in the study area.There was a significant difference in nematode abundance(ANOVA,F=2.38,P<0.05)between the three sites.Nematode communities were characterized by a high level of species diversity in sediments composed mainly of very-fine sands(>63μm),with dominant species belonging to the genus Bathylaimus,Ptycho-laimellus,Spirinia,and Sabatieria.The trophic groups were dominated by non-selective deposit feeders(40.7%)and epistrate feed-ers(41.29%).In contrast,the species composition in medium grain sands was characterized by a low species diversity index and a high Simpson dominance index.Nematode communities showed similar dominant species compositions belonging to a single genus Bathylaimus,Enoplolaimus,and Oncholaimus,and in terms of trophic structure-representatives of deposit feeders(46.15%),preda-tors,and omnivores(64.71%)prevailed.The divergence of meiofaunal community structures can be explained by abiotic factors such as sediment grain size,salinity,and organic carbon content.Specifically,sediment particle size can explain the diversity of nematodes at the level of in abundance,diversity indices,and trophic structure.The highest nematode density and diversity coincided with the highest percentage of very fine sands.
文摘Objective: To explore the antibacterial activity of combined use of Shuanghuanglian and cefoperazone sulbactam sodium on resistant strains of Pseudomonas aeruginosa. Methods: The Pseudomonas aeruginosa strains which were sensitive and resistant to cefoperazone sulbactam sodium were selected to prepare different test bacterial solutions respectively;The experimental liquid of Shuanghuanglian and Cefoperazone Sulbactam Sodium were prepared separately and set as different test groups and control groups;The Drug Sensitivity Tests of Shuanghuanglian and cefoperazone sulbactam sodium at different concentration gradients which were used alone or used in combination were carried out for different strains with sensitivity and resistance, And use standard entry as a reference control. Result: The results of drug sensitivity test of Shuanghuanglian combined with Cefoperazone-Sulbactam sodium against the resistant strains of Pseudomonas aeruginosa were compared with the results of drug sensitivity test of the two separately used, and the difference was statistically significant (P 〈 0.05) [The drug sensitivity test results of Shuanghuanglian and cefoperazone sulbactam sodium to Pseudomonas aeruginosa resistant strains were statistically significant compared with the drug sensitivity test results of Shuanghuanglian and Cefoperazone Sulbactam Sodium used separately (P 〈 0.05)];There was a dependence between strains and concentration in the effect of the combination of the two drugs. Conclusion: The combination of Shuanghuanglian and cefoperazone sulbactam sodium has synergistic antibacterial or bactericidal effect on Pseudomonas aeruginosa resistant strains. .
基金Supported by the Strategic Priority Research Program of Chinese Academy of Sciences(CAS)(No.XDA11020305)the National Natural Science Foundation of China(No.41576032)the International Cooperation in Key Projects,CAS(Detection of Oil Spill and Its Ecological Impact(No.133337KYSB20160002)
文摘The Bohai Sea is a low-lying semi-enclosed sea area that is linked to the Yellow Sea via the Bohai straits(mixed zone). Its of fshore seabed is shallow, which makes it vulnerable to serious marine meteorological disasters associated with the northward passage of Pacific tropical cyclones. Analyses on data of remote sensing and buoy of the mixed zone of the Yellow and Bohai seas indicate that all the wind speed, significant wave height, and salinity(SAL) increased, sea surface temperature decreased, and wind energy density changed considerably during the passage of tropical cyclone Matmo on July 25, 2014. It was found that the SAL inversion layer in the mixed zone of the Yellow and Bohai Seas was caused by the tropical cyclone. Furthermore, it was found that the tropical cyclone transported the northern Yellow Sea cold water mass(NYSCWM) into the mixed zone of the Yellow and Bohai Seas. The NYSCWM has direct influence on both the aquaculture and the ecological environment of the region. Therefore, further research is needed to establish the mechanism behind the formation of the SAL inversion layer in the mixed zone, and to determine the influence of tropical cyclones on the NYSCWM.
文摘Background: Inadequate human resources are a major constraint to improving global health. The health sector is characterized by a high turnover coupled with internal as well as external brain drain but there is little information on intention to leave among health professionals in public health centers of Jimma Zone, Oromia Regional State. The aim of this study is to assess intention to leave and associated factors among health professionals in public health centers of Jimma Zone, southwest Ethiopia. Methods: A cross-sectional quantitative and qualitative study was conducted on seven randomly selected woredas (districts) which have 53 public health centers. All health professionals in sampled district public health centers were included (n = 505). Factor analysis was employed for all Likert scale instruments to extract factor(s) representing each of the scales using SPSS version 16.0. The qualitative data was analyzed by thematic analysis methods. Ethical approval was obtained from Jimma University. Results: Four hundred fifty five (90.1%) health professionals participated in the study;out of this, 290 (63.7%) had intention to leave. Among variables, job satisfaction (Beta = -0.298, (95% CI, -0.568 to -0.029), working environment (Beta = -0.612, (95% CI, -0.955 to -0.270), and organizational management (Beta = -0.552, (95% CI, 0.289 to 0.815) had statistically significant association with intention to leave among health professionals in public health centers of Jimma Zone. Conclusions: The overall intention to leave among health professionals was high. Level of job satisfaction, working environment, work pressure, and organizational management had statistically significant association with intention to leave. Thus, responsible bodies should aggressively work on the concerns identified, like, improvements in salary, promotion in terms of training/educational opportunity, improving working environment, and transfer of health professionals, and improvement of the leadership skills of managers.
文摘This study investigates the relationship between demographic characteristics （company type, company ownership, company operating years, and sector） and supply logistics characteristics （source of supplies, average number of suppliers for their products, replenishment frequency for their orders, and relationship with their suppliers） of companies that are operating in Mersin Free Zone along with their supplier selection criteria based on the 36 companies selected through convenience sampling. The finding implies that the relationships of company type---replenishment frequency, company type---relationship among suppliers, and company ownership---source of supplies are significant at the 95% confidence level. Besides, the most significant three supplier selection criteria are found to be quality, price, and delivery time respectively, while the least important three ones appear to be nationality （foreign/domestic） and the reputation of the supplier respectively.
文摘Since the 18th National Congress of the Communist Party of China held in 2012,the construction of pilot free trade zone has emerged as a strategically important approach for China’s reform and opening up efforts.These zones exemplify China’s proactive and open strategy,serving as a key driver for promoting high-quality development.In September 2013,China launched its first pilot free trade zone,China(Shanghai)Pilot Free Trade Zone.Over the past decade,21 additional pilot free trade zones have been established across the country.This expansion has created a comprehensive reform and opening up innovation agenda that spans the eastern,western,southern,northern,and central regions,while integrating coastal,inland,and border areas.
基金Under the auspices of Open Research Fund Program of Shandong Key Laboratory for Yellow River Delta Eco-Environmental Science,Binzhou,China (No.2007KFJJ01)Knowledge Innovation Programs of Chinese Academy of Sciences (No.KZCX2-YW-223)+1 种基金National Natural Science Foundation of China (No.40803023,41171424)Key Program of Natural Science Foundation of Shandong Province (No.ZR2010DZ001)
文摘From April 2008 to November 2009, the nitrogen （N） cycle of plant-soil system in seepweed （Suaeda salsa） wetland in the intertidal zone of the Huanghe （Yellow） River estuary was studied. Results showed that soil N had sig- nificant seasonal fluctuations and vertical distribution, and the net N mineralization rates in topsoil were significantly different in growing season （p 〈 0.01）. The N/P ratio （9.87 ±1.23） of S. salsa was less than 14, indicating that plant growth was limited by N. The N accumulated in S. salsa litter at all times during decomposition, which was ascribed to the N immobilization by microbes from the environment. Soil organic N was the main N stock of plant-soil system, accounting for 97.35% of the total N stock. The N absorption and utilization coefficients of S. salsa were very low （0.0145 and 0.3844, respectively）, while the N cycle coefficient was high （0.7108）. The results of the N turnovers among compartments of S. salsa wetland showed that the N uptake amount of aboveground part and root were 7.764 g/m2and 4.332 g/m2, respectively. The N translocation amounts from aboveground part to root and from root to soil were 3.881 g/m2 and 0.626 g/m2, respectively. The N translocation amount from aboveground living body to litter was 3.883 g/m2, the annual N return amount from litter to soil was more than 0.125（-） g/m2 （minus represented immobili- zation）, and the net N mineralization amount in topsoil （0-15 cm） in growing season was 1.190 g/m2. The assessment of N biological cycle status orS. salsa wetland indicated that N was a very important limiting factor and the ecosystem was situated in unstable and vulnerable status. The S. salsa was seemingly well adapted to the low-nutrient status and vulnerable habitat, and the N quantitative relationships determined in the compartment model might provide scientific base for us to reveal the special adaptive strategy orS. salsa to the vulnerable habitat in the following studies.
文摘The opening of the Panama Canal in 1913 transformed ocean-shipping and the availability of internationally-traded goods, shortened travel time between the Pacific and Atlantic oceans, increased ship tonnage, and sparked the growth of port authorities on both the Atlantic and Pacific coasts of the Panama Canal. Historically, the United States was number one and China was number two in tons of cargo that pass through the canal annually in the high stakes game of import and export markets. Prior to the construction of the Panama Canal, the most efficient way to cross the 82-kilometer isthmus, between the Port of Panama City on the Pacific and the Port of Colon on the Atlantic, was by mule trails through tropical forests and river transportation. Since the construction of the Panama Canal through tropical forests in the 1910s, pesticides have been essential for managing mosquitoes as well as controlling wetland vegetation that blocked lakes, rivers and the canal. The pri<span>mary objective of this research study is to document the long-term environmental impacts of pesticide and herbicide use in the Panama Canal Zone. Many of these chemicals, including 2, 4,-D, 2, 4, 5-T and DDT, have a long half-life under water and some, like arsenic (As), have no half-life. Pesticides </span>and chemicals flowed into Lake Gatun via surface runoff either in solution or attached to the sediment during the rainy season. The by-product 2,3,7,8-tetrachlorodibenzo-<i>p</i>-dioxin (TCDD) is an unanticipated contaminant created during the manufacture of the herbicide 2,4,5-T. TCDD can bio-accumulate in fish and birds and enter into the human food supply. The extent of the current chemical and pesticide contamination on former U.S. military base grounds and in Lake Gatun is unknown. Systematic soil sampling of current and former military bases, chemical disposal sites and Lake Gatun or the Panama Canal sediments is needed to determine if mitigation is necessary.
基金Financial support for this study was kindly provided by the National Natural Science Foundation Project of China(No.51804246,No.52174202)Natural Science Foundation of Xinjiang Province(No.2019D01C057)the Youth Talent Promotion Program of Shaanxi University Association for Science and Technology(No.20200425).
文摘Temperature variation and gas generation at diferent depths and positions in the coal combustion process were studied to determine the propagation and evolution of high temperature regions in the process of coal spontaneous combustion.This study selected coal samples from Mengcun,Shaanxi Province,People’s Republic of China,and developed a semi-enclosed experimental system(furnace)for simulating coal combustion.The thermal mass loss of coal samples under various heating rates(5,10,and 15℃/min)was analyzed through thermogravimetric analysis,and the dynamic characteristics of the coal samples were analyzed;the reliability of the semi-enclosed experimental system was verifed through the equal proportional method of fuzzy response.The results reveal that the high-temperature zone is distributed nonlinearly from the middle to the front end of the furnace,and the temperatures of points in this zone decreased gradually as the layer depth increased.The apparent activation energy of the coal samples during combustion frst increased and then decreased as the conversion degree increased.Furthermore,the proportion of mass loss and the mass loss rate in the coal samples observed in the thermogravimetric experiment is consistent with that observed in the frst and second stages of the experiment conducted using the semi-enclosed system.The research fndings can provide a theoretical basis for the prevention and control of hightemperature zones in coal combustion.
基金Supported by the "SUST Spring Bud" (No.2008AZZ110)the National Key Technology R&D Program of China (No.2006BAJ15B02)
文摘Geographical design of riparian buffers with long-term vegetation cover for environmental restoration in agricultural watersheds needs to assess how much farmland is located in the buffers of a concerned watershed. Traditionally, this assessment was done by field surveying and manual mapping, which was a time-consuming and costly process for a large region. In this paper, remote sensing （RS） and geographical information system （GIS） as cost-effective techniques were used to develop a catchments-based approach for identifying critical sites of agricultural riparian buffer restoration. The method was explained through a case study of watershed with ll catchments and results showed that only four of the catchments were eligible in terms of higher priority for riparian buffer restoration. This research has methodological contributions to the spatial assessment of farming intensities in catchments-based riparian buffers across a watershed and to the geographical designs of variable buffering scenarios within catchments. The former makes the catchments-based management strategy possible, and the latter provides alternative restoration scenarios to meet different management purposes, both of which have direct implementations to the environmental restoration of riparian buffers in the real world. This study, thus, highlights the great potential of RS and GIS applications to the planning and management of riparian buffer restoration in agricultural watersheds.
文摘The Moroccan territory is often exposed to brutal and destructive floods. The latter is triggered by intense rains and sudden duration (rain showers, thunderstorms). The human and material damage caused by these floods has always been very high. The violence of the flood (1000 m<sup>3</sup>/s) of Oued Ourika on Aug 17, 1995, killed 730 people. The material damage caused by torrential rain only for the years 2008 and 2009 on the road network (roads and civil engineering works) represents more than 2.9 billion dirhams. The development of flood protection studies requires the values of the instantaneous frequency flow of a certain probability and the corresponding flood hydrogram, generally, these values are not available in the watersheds studied. The objective of this study is to propose for the Moroccan territory a method of calculating flood flows and hydrographs of floods for stream and wadis ungauged for the benefit of engineers and planners for possible studies of flood protection. The proposed method is based on the delimitation of homogeneous regions of Moroccan territory (three homogeneous regions). The frequency analysis carried out for these three zones made it possible to identify the climatic parameters necessary to calculate the flood index and consequently the frequency floods. The proposed Galton type flood hydrograph includes three parameters namely the rise time, the shape parameter and the flood index. These latter parameters are easily calculated by the formulas proposed.
文摘Lamb morbidity and mortality cause significant loss in a smallholder production system. A longitudinal prospectivesurvey was conducted on 408 randomly selected farmers located in six purposefully selected kebeles in Gewataworeda from June 2020 to July 2021 to determine the incidence of morbidity and mortality in lambs and to identifyrisk factors. For this purpose, 408 lambs from the Gewata district’s mixed crop-livestock production system wereexamined every day from birth to three months of age. The data was analyzed using the Kaplan-Meier (K-M) method,the log-rank test, and Cox proportional hazards regression. Results showed that the cumulative incidence of allcauseof morbidity and mortality at the end of three month was 12.86% (95% CI: 10.26–16.13%), and 6.86% (95% CI:5.03–9.35%), respectively. Diarrhea was the leading cause of morbidity and mortality, accounting for 49.33 and 50%morbidity and mortality, respectively. Pneumonia was the second most frequent cause of morbidity and death. In theK-M hazard analysis, the greatest risk of lamb morbidity and mortality was observed during the first month of life, andthen the risk decreased significantly as the lamb grew. Of the 17 potential risk factors studied, the multivariable Coxproportional hazards regression model showed that lamb sex, birth weight, umbilical care, time and method of colostrumfeeding were the five predictors that were significantly associated with a higher risk of morbidity, whereas birthweight, lambing difficulty, dams’ parity, method and time of colostrum feeding were the five predictors that weresignificantly associated with a higher risk of mortality. Moreover, a higher risk of morbidity was observed in lambswith methods of colostrum feeding after birth (HR = 3.158;p = 0.000) and with variations in birth weight (HR = 1.418;p = 0.003). Similarly, the mortality risk was 4.926 (p = 0.047), 4.023 (p = 0.012), and 3.206 (p = 0.000) times higher inlambs with lambing difficulties, at the time of colostrum feeding, and by the method of colostrum feeding, respectively.According to this research, lamb morbidity and mortality rates in the study area are significantly high whichhas a great impact on the replacement stock and production. Hence, awareness should be created among farmersconcerning improved lamb management practices.
文摘Peatlands represent one of the most important economic resources and abandoned peatlands after mining can be considered as ecological resources by re-vegetation restoration or management. However, some environmental problems like particles from peatlands and their effects in the water system have to be characterized. Since centuries, artificial drainage has been a current practice for the mining of peatlands. Mainly mined for horticultural purpose, New Brunswick＇s peatlands--predominantly located in the eastern of the province--cover about 140,000 ha. At the downstream end of the drainage system, the water from peatlands flow into sedimentation basins. Drainage waters are often laden with solid particles. Once they have flowed through the ponds to allow sediment settling, the water is released into the water system. This paper describes the spatio-temporal evolution of suspended solids from 12 New Brunswick drained peatlands. The studied sites were characterized by some heterogeneity in the concentration of suspended solids. This study also provides knowledge on the suspended solids amount that can be released by drained peatlands, and it proposes a function to estimate the concentration of suspended solids by using climate variables; and identifies some potential ecological risks.
文摘Background: Disclosure of HIV sero status is among varies HIV prevention strategy to prevent the spread of HIV. It is the base for accessing care and treatment programs, attains psycho-social support and reduces stigma, adheres to treatment and promotes safer health behavior particularly for couples. Objective: To assess HIV sero status disclosure to sexual partner and associated factors among HIV positive adult patient in Bale Zone hospitals. Method: A cross-sectional study design was conducted among 411 adult HIV positive clients who were selected by using systematic random sampling methods from Bale Zone Hospitals. Data were collected by using pre-tested questionnaire after verbal consent obtained from participants by trained nurse. Multiple logistic regression analysis was done by using SPSS version 20 and P-value of less than 0.05 was taken to declare statistical significance. Result: HIV sero status disclosure to sexual partners was 52.6%. Residence (AOR = 1.62;95% CI, 1.0, 2.60), receiving pre-test counselling related disclosure (AOR = 6.25;95% CI, 3.45, 11.33) and knowledge of partner’s HIV sero status (P-Value = 0.001) were significantly associated with HIV sero status disclosure. Fear of stigma and violence by sexual partner were the main reasons suggested for not disclosing HIV sero-status. Conclusion: The level of HIV sero-status disclosure to sexual partner was low. Disclosure of HIV sero status to sexual partner was significantly associated with clients’ place of residence, receiving pre-test counselling about disclosure and Knowledge of partners HIV sero status.
