Mierocystis aeruginosa FACHB 905 was used as a model organism to study the ellects oI small water clusters (SWCs) on the growth and microcystin (MC) production of toxic cyanobacteria. The results showed that SWCs ...Mierocystis aeruginosa FACHB 905 was used as a model organism to study the ellects oI small water clusters (SWCs) on the growth and microcystin (MC) production of toxic cyanobacteria. The results showed that SWCs were able to stimulate the growth of Microcystis aeruginosa, which resulted in increased cell numbers and higher specific growth rates after a 30-d treatment. The cell morphology indicated that Microcystis aeruginosa was in a better state of growth, and it was more prone to divide in SWCs than in normal water clusters. The SWCs treatment up-regulated MC synthesis and exudation in 10 d in Microcystis aeruginosa, and the intra-cellular MC content de- creased after the 20th day subsequently. Moreover, the cellular photosynthetic pigment contents were temporarily stimulated by SWCs. A possible reason is that SWCs stimulated the growth by promoting photosynthesis, whereas the increased MC production was relevant to pigment contents.展开更多
The intermolecular clusters of sulfur dioxide with water, SO2(H2O)n (n = 2~5), are studied by using B3LYP density functional theory and MP2 ab initio methods along with the large basis sets (6-311++G(d,p) an...The intermolecular clusters of sulfur dioxide with water, SO2(H2O)n (n = 2~5), are studied by using B3LYP density functional theory and MP2 ab initio methods along with the large basis sets (6-311++G(d,p) and aug-cc-pVDZ). The equilibrium geometries, intermolecular binding energies, and anharmonic frequencies of the clusters are calculated and compared with those of pure water clusters and available experiments. SO2 tends to form cyclic hydrogen-bonded complexes with two or three water molecules. In the larger clusters, however, water molecules begin to retain the structure of pure water clusters and segregate from SO2. Infrared absorption assignments for the small clusters are discussed to resolve a possible incorrect assignment in a recent spectroscopic experiment on the clusters.展开更多
The study was conducted to determine the socioeconomic impact two (2) Small Water Impounding Projects (SWIPs) namely Burgos SWIP in Cabarroguis and Divisoria Norte SWIP in Maddela, both in the Province of Quirino, Phi...The study was conducted to determine the socioeconomic impact two (2) Small Water Impounding Projects (SWIPs) namely Burgos SWIP in Cabarroguis and Divisoria Norte SWIP in Maddela, both in the Province of Quirino, Philippines. The study made use of structured questionnaire to gather the socio-demographic profile and determined the socioeconomic impact of the SWIPs to the farmer-beneficiaries. Most of the farmer-beneficiaries of Burgos and Divisoria Norte SWIPs are male, 40 - 59 years old, married, have below four household members, Roman Catholic, high school graduates and some are members of cooperatives. They are rice farmers, and have attended one to two training courses related to farming and own a 1.00 to 1.99 hectares farm. “Utilization of water in the reservoir for other purposes like wallowing pool for carabaos” and “integration of fish production and livestock raising” were the identified benefits at the farmer’s level while “introduction of new techniques in farming by the Local Government Units,” “availability of cheap fish and additional income as a result of integration of fish production” and “construction of better roads” were the identified benefits at the community level. The SWIPs have positive impact as confirmed by the increase in the annual mean yield and in the annual gross income of the farmer-beneficiaries. It contributed a significant increase of 2.14 tons/year in the mean yield generating an additional income of PhP 32,113.64 for Burgos SWIP. On the other hand, it contributed a significant increase of 2.08 tons/year giving an additional income of PhP 31,313.60 for Divisoria Norte farmer-beneficiaries. The result of this study will provide strategic information to policy makers of agricultural and irrigation agencies on the existing weaknesses of irrigation systems in the country and determine in a more quantifiable terms level of potential improvement and investment targets.展开更多
This paper takes Hebei province of small water conservancy facilities construction project as the research object, the performance evaluation purposes of construction of farmland water conservancy facilities project, ...This paper takes Hebei province of small water conservancy facilities construction project as the research object, the performance evaluation purposes of construction of farmland water conservancy facilities project, the data sources when carry out performance evaluation, performance evaluation procedures and limitations of farmland water conservancy facilities construction project performance evaluation were discussed.展开更多
The small and scattered enterprise pattern in the county economy has formed numerous sporadic pollution sources, hindering the centralized treatment of the water environment, increasing the cost and difficulty of trea...The small and scattered enterprise pattern in the county economy has formed numerous sporadic pollution sources, hindering the centralized treatment of the water environment, increasing the cost and difficulty of treatment. How enterprises can make reasonable decisions on their water environment behavior based on the external environment and their own factors is of great significance for scientifically and effectively designing water environment regulation mechanisms. Based on optimal control theory, this study investigates the design of contractual mechanisms for water environmental regulation for small and medium-sized enterprises. The enterprise is regarded as an independent economic entity that can adopt optimal control strategies to maximize its own interests. Based on the participation of multiple subjects including the government, enterprises, and the public, an optimal control strategy model for enterprises under contractual water environmental regulation is constructed using optimal control theory, and a method for calculating the amount of unit pollutant penalties is derived. The water pollutant treatment cost data of a paper company is selected to conduct empirical numerical analysis on the model. The results show that the increase in the probability of government regulation and public participation, as well as the decrease in local government protection for enterprises, can achieve the same regulatory effect while reducing the number of administrative penalties per unit. Finally, the implementation process of contractual water environmental regulation for small and medium-sized enterprises is designed.展开更多
Inland water bodies,including ponds,lakes,reservoirs,and rivers,provide extensive ecosystem services for human beings.Among these,small water bodies(SWBs),such as ponds and small reservoirs,are more common landscape f...Inland water bodies,including ponds,lakes,reservoirs,and rivers,provide extensive ecosystem services for human beings.Among these,small water bodies(SWBs),such as ponds and small reservoirs,are more common landscape features and important biogeochemical reactors.SWBs can significantly influence biogeochemical processes and hydrologic cycles.However,due to their small size,SWBs(<10 ha)have been largely ignored in natural resource surveys,leading to a limited understanding of their spatial distribution in China.Insufficient geospatial datasets of SWBs limit the accurate assessments of resource utilization and fluxes of biogenic elements in both aquatic and terrestrial ecosystems.To address this,in this study,we applied a convolutional neural network and a visual interpretation approach to extract SWBs from high-resolution satellite images from Google Earth.The spatial distribution of SWBs in China was mapped,and drivers of the spatial pattern of SWBs were also identified.As a result,a total of 5.18 million water bodies with a surface area larger than 0.1 ha,including ponds,lakes,and reservoirs,were identified.These water bodies(>0.1 ha)cover approximately 179300 km^(2),which is approximately 1.8%of the land area in China.In addition,the combined shoreline length of the water bodies was approximately 2157400 km.Of these water bodies,96.85%were SWBs,accounting for 17.85%of the total water area and 76.4% of the total shoreline length.Precipitation,terrain,and human activity cumulatively explained 45% of the variance in SWB distribution,with precipitation being the strongest climatic explanatory factor.Our results provide important data for determining the roles of SWBs in biogeochemical cycles,habitat protection,and hydrological cycles.展开更多
The flow characteristics and cavitation effects of water passing throughsmall sharp-edged cylindrical orifices and valves of different shapes in water hydraulics areinvestigated. The test results using orifices with d...The flow characteristics and cavitation effects of water passing throughsmall sharp-edged cylindrical orifices and valves of different shapes in water hydraulics areinvestigated. The test results using orifices with different aspect ratios and different diametersshow that the flow coefficients in the case of non-cavitating flow are larger than that of flow inthe case of cavitation occurrence. The flow coefficients of flow with cavitation initially decreaseas Reynolds number increases and ultimately tend to be of constant values close to contractioncoefficient. Large aspect ratio has an effect of suppressing cavitation. The experimental resultsabout disc valves illustrate that the valves with sharp edge at large opening are less affected bycavitation than that at small opening. Throttle with triangle notch has better anti-cavitationability than that with square notch. The flowrate of the throttle with square notch is significantlyaffected by the flow direction or the flow passage shape.展开更多
Background: Following the intake of Fusarium mycotoxin-contaminated feed,small intestines may be exposed to high levels of toxic substances that can potentially damage intestinal functions in livestock.It is well know...Background: Following the intake of Fusarium mycotoxin-contaminated feed,small intestines may be exposed to high levels of toxic substances that can potentially damage intestinal functions in livestock.It is well known that Fusarium mycotoxins will lead a breakdown of the normally impeccable epithelial barrier,resulting in the development of a "leaky" gut.H2 administration with different methods has been proved definitely potentials to prevent serious intestinal diseases.The goal of this study is to investigate the roles of lactulose(LAC) and hydrogenrich water(HRW) in preventing intestinal dysfunction in piglets fed Fusarium mycotoxin-contaminated feed.Methods: A total of 24 female piglets were evenly assigned to 4 groups: negative control(NC) group,mycotoxincontaminated(MC) feed group,MC feed with LAC treatment(MC + LAC),and MC feed with HRW treatment(MC +HRW),respectively.Piglets in the NC group were fed uncontaminated control diet,while remaining piglets were fed Fusarium mycotoxin-contaminated diet.For the NC and MC groups,10 mL/kg body weight(BW) of hydrogen-free water(HFW) was orally administrated to piglets twice daily;while in the MC + LAC and MC + HRW groups,piglets were treated with the same dose of LAC solution(500 mg/kg BW) and HRW twice daily,respectively.On d 25,serum was collected and used for biochemical analysis.Intestinal tissues were sampled for morphological examination as well as relative genes and protein expression analysis.Results: Our data showed that Fusarium mycotoxins induced higher serum diamine oxidase(DAO) activities(P < 0.05),D-lactic acid levels(P < 0.01),and endotoxin status(P < 0.01),lower villus height(P < 0.01) and ratio of villus height to crypt depth(P < 0.05) in small intestine,greater apoptosis index and higher mRNA expression related to tight junctions(P < 0.05).In addition,the distribution and down-regulation of claudin-3(CLDN3) protein in the small intestinal was also observed.As expected,oral administrations of HRW and LAC were found to remarkably provide beneficial effects against Fusarium mycotoxin-induced apoptosis and intestinal leaking.Moreover,either HRW or LAC treatments were also revealed to prevent abnormal intestinal morphological changes,disintegrate tight junctions,and restore the expression and distribution of CLDN3 protein in the small intestinal mucosal layer in female piglets that were fed Fusarium mycotoxins contaminated diet.Conclusions: Our data suggest that orally administrations of HRW and LAC result in less Fusarium mycotoxininduced apoptosis and leak in the small intestine.Either HRW or LAC treatments could prevent the abnormal changes of intestinal morphology and molecular response of tight junctions as well as restore the distribution and expression of CLDN3 protein of small intestinal mucosa layer in female piglets that were fed Fusarium mycotoxins contaminated diet.展开更多
Taking the water ecosystem of Small Xingkai Lake as research object,through the survey and analysis of aquatic organism indicators,this paper established an ecosystem integrity evaluation system with the biological in...Taking the water ecosystem of Small Xingkai Lake as research object,through the survey and analysis of aquatic organism indicators,this paper established an ecosystem integrity evaluation system with the biological integrity as the criterion layer. Using the index of biological integrity and comprehensive health index,it evaluated the health status of water ecosystem of Small Xingkai Lake.展开更多
Based on the health risk assessment model of water quality recommended by United States Environmental Protection Agency (USEPA), the health risk of five centralized drinking water sources in small towns of Beibei Dist...Based on the health risk assessment model of water quality recommended by United States Environmental Protection Agency (USEPA), the health risk of five centralized drinking water sources in small towns of Beibei District, Chongqing City was evaluated. The results showed that the risk of health hazard of chemical carcinogen arsenic did not exceed the acceptable level recommended by the International Commission on Radiological Protection (ICRP)(5.0×10 -5 a -1 ), but was still at the same order of magnitude as the recommended value of ICRP. The risk of the highest health hazard was 127 times higher than the maximum acceptable level recommended by Sweden EPA and Holland EPA (1.0×10 -6 a -1 ). The health risk of As in genetic toxic substances at monitoring points A, B, and C accounted for 99.99% of the total risk, showing that As was the main pollutant that posed the health risk, so priority should be given to the prevention and control of As pollution in the centralized drinking water sources in Chongqing towns.展开更多
The relationship between the spatiotemporal distribution of three dominant small pelagic fishes,including chub mackerel(Scomber japonicus),horse mackerel(Trachurus trecae)and round sardinella(Sardinella aurita),and th...The relationship between the spatiotemporal distribution of three dominant small pelagic fishes,including chub mackerel(Scomber japonicus),horse mackerel(Trachurus trecae)and round sardinella(Sardinella aurita),and the environmental factors in Mauritanian waters were analyzed by using 4 years of logbook data of commercial purse seine fisheries to improve the efficiency of fishery and management of sustainable exploitation.A Tweedie-generalized additive model(GAM)of 8-day average catches and the monthly geostatistical analysis of daily catches were used in this study to analyze the influence of environmental factors on catch per unit of effort(CPUEs)and to map the spatial distribution of three mixed dominant small pelagic fishes,respectively.A 10'×10' grid was used,and environmental factors were processed from remote sensing,including 8-day average sea surface temperature(SST),the nearest distance between SST fronts and CPUE position(Df),chlorophyll-a(Chl-a)concentration,salinity,and eddy kinetic energy.Results showed that 1)the distribution of three dominant small pelagic fishes might be related to the intensity of upwelling in Mauritanian waters;2)oceanic fronts might play a key role in the ecology of chub mackerel,horse mackerel,and round sardinella;3)Chl-a concentration might be associated with the feeding grounds of chub mackerel;4)the target species distribution appeared sensitive to gradient changes in the amount of salinity;5)three zones(northern,central,and southern)with variable abundances were delineated;and 6)a high concentration of the center of gravity in the central zone might be related to the strong upwelling of nutrient-rich waters.This study can provide new insights to enhance the fishery efficiency and sustainable exploitation management of purse seiners in certain area off Mauritania.展开更多
In karst area water deficit is one of the main factors constraining sustainable economic development. In 1979 the comprehensive karstic observational field station was set up in Houzhai drainage basin located,\ in Pud...In karst area water deficit is one of the main factors constraining sustainable economic development. In 1979 the comprehensive karstic observational field station was set up in Houzhai drainage basin located,\ in Puding county of Guizhou Province, which can represent most of the small karst drainage basins on the dividing line of the Guizhou Plateau. Geomorphology, water resources and water chemistry were investigated and observed. Based on comparisons of water supply with water demand and analysis of the main problems in water exploitation and utilization. it is found out that the water deficiency was not directly caused by the scarcity of natural water resources. The true reason is the insufficient capacity of water supply caused by the dismatch of the water and soil water resources which can be dealt with by building more irrigation works. Some solutions such as to build scientific basis for water exploitation and utilization and sustainable economic development in karst drainage basins on dividing line of the Guizhou Plateau.展开更多
针对水面目标检测中的噪声干扰和小目标的漏检问题,提出一种改进YOLOv8的水面小目标检测算法YOLOv8-WSSOD(YOLOv8-water surface small object detection).首先,为降低水面复杂环境在主干网络下采样过程中产生的噪声干扰,提出基于BiFor...针对水面目标检测中的噪声干扰和小目标的漏检问题,提出一种改进YOLOv8的水面小目标检测算法YOLOv8-WSSOD(YOLOv8-water surface small object detection).首先,为降低水面复杂环境在主干网络下采样过程中产生的噪声干扰,提出基于BiFormer双层路由注意力机制构建的C2fBF(C2f-BiFormer)模块,在特征提取过程中保留细粒度的上下文特征信息;其次,针对水面小目标的漏检问题,新增一个更小的检测头,提升网络对小目标的感知力,并在Neck端引入GSConv和Slim-neck,减轻模型复杂度并保持精度;最后,使用MPDIoU损失函数解决CIoU损失函数的局限性,以提高模型检测准确率.实验结果表明,相较于原始YOLOv8算法,该算法在水面小目标上平均准确率mAP@0.5提升了4.6%,mAP@0.5:0.95提升了2.2%,并且改进后的算法检测速度达到86f/s,能有效实现对水面小目标快速、准确的检测.展开更多
基金Supported by National High Technology Research and Development Program of China ("863" Program,No.2012AA063504)National Natural Science Foundation of China(No.20676094)Scientific Project of Ocean Development of Tianjin Oceanic Administration(No.KJXH2011-10)
文摘Mierocystis aeruginosa FACHB 905 was used as a model organism to study the ellects oI small water clusters (SWCs) on the growth and microcystin (MC) production of toxic cyanobacteria. The results showed that SWCs were able to stimulate the growth of Microcystis aeruginosa, which resulted in increased cell numbers and higher specific growth rates after a 30-d treatment. The cell morphology indicated that Microcystis aeruginosa was in a better state of growth, and it was more prone to divide in SWCs than in normal water clusters. The SWCs treatment up-regulated MC synthesis and exudation in 10 d in Microcystis aeruginosa, and the intra-cellular MC content de- creased after the 20th day subsequently. Moreover, the cellular photosynthetic pigment contents were temporarily stimulated by SWCs. A possible reason is that SWCs stimulated the growth by promoting photosynthesis, whereas the increased MC production was relevant to pigment contents.
基金supported by the National Natural Science Foundation of China (20528706)the China Postdoctoral Science Foundation (20090450385)
文摘The intermolecular clusters of sulfur dioxide with water, SO2(H2O)n (n = 2~5), are studied by using B3LYP density functional theory and MP2 ab initio methods along with the large basis sets (6-311++G(d,p) and aug-cc-pVDZ). The equilibrium geometries, intermolecular binding energies, and anharmonic frequencies of the clusters are calculated and compared with those of pure water clusters and available experiments. SO2 tends to form cyclic hydrogen-bonded complexes with two or three water molecules. In the larger clusters, however, water molecules begin to retain the structure of pure water clusters and segregate from SO2. Infrared absorption assignments for the small clusters are discussed to resolve a possible incorrect assignment in a recent spectroscopic experiment on the clusters.
文摘The study was conducted to determine the socioeconomic impact two (2) Small Water Impounding Projects (SWIPs) namely Burgos SWIP in Cabarroguis and Divisoria Norte SWIP in Maddela, both in the Province of Quirino, Philippines. The study made use of structured questionnaire to gather the socio-demographic profile and determined the socioeconomic impact of the SWIPs to the farmer-beneficiaries. Most of the farmer-beneficiaries of Burgos and Divisoria Norte SWIPs are male, 40 - 59 years old, married, have below four household members, Roman Catholic, high school graduates and some are members of cooperatives. They are rice farmers, and have attended one to two training courses related to farming and own a 1.00 to 1.99 hectares farm. “Utilization of water in the reservoir for other purposes like wallowing pool for carabaos” and “integration of fish production and livestock raising” were the identified benefits at the farmer’s level while “introduction of new techniques in farming by the Local Government Units,” “availability of cheap fish and additional income as a result of integration of fish production” and “construction of better roads” were the identified benefits at the community level. The SWIPs have positive impact as confirmed by the increase in the annual mean yield and in the annual gross income of the farmer-beneficiaries. It contributed a significant increase of 2.14 tons/year in the mean yield generating an additional income of PhP 32,113.64 for Burgos SWIP. On the other hand, it contributed a significant increase of 2.08 tons/year giving an additional income of PhP 31,313.60 for Divisoria Norte farmer-beneficiaries. The result of this study will provide strategic information to policy makers of agricultural and irrigation agencies on the existing weaknesses of irrigation systems in the country and determine in a more quantifiable terms level of potential improvement and investment targets.
文摘This paper takes Hebei province of small water conservancy facilities construction project as the research object, the performance evaluation purposes of construction of farmland water conservancy facilities project, the data sources when carry out performance evaluation, performance evaluation procedures and limitations of farmland water conservancy facilities construction project performance evaluation were discussed.
文摘The small and scattered enterprise pattern in the county economy has formed numerous sporadic pollution sources, hindering the centralized treatment of the water environment, increasing the cost and difficulty of treatment. How enterprises can make reasonable decisions on their water environment behavior based on the external environment and their own factors is of great significance for scientifically and effectively designing water environment regulation mechanisms. Based on optimal control theory, this study investigates the design of contractual mechanisms for water environmental regulation for small and medium-sized enterprises. The enterprise is regarded as an independent economic entity that can adopt optimal control strategies to maximize its own interests. Based on the participation of multiple subjects including the government, enterprises, and the public, an optimal control strategy model for enterprises under contractual water environmental regulation is constructed using optimal control theory, and a method for calculating the amount of unit pollutant penalties is derived. The water pollutant treatment cost data of a paper company is selected to conduct empirical numerical analysis on the model. The results show that the increase in the probability of government regulation and public participation, as well as the decrease in local government protection for enterprises, can achieve the same regulatory effect while reducing the number of administrative penalties per unit. Finally, the implementation process of contractual water environmental regulation for small and medium-sized enterprises is designed.
基金supported by the Strategic Priority Research Program(A)of the Chinese Academy of 502 Sciences(Grant No.XDA23040303)the National Natural Science Foundation of China(Grant No.42071242)the West Light Foundation of the Chinese Academy of Sciences。
文摘Inland water bodies,including ponds,lakes,reservoirs,and rivers,provide extensive ecosystem services for human beings.Among these,small water bodies(SWBs),such as ponds and small reservoirs,are more common landscape features and important biogeochemical reactors.SWBs can significantly influence biogeochemical processes and hydrologic cycles.However,due to their small size,SWBs(<10 ha)have been largely ignored in natural resource surveys,leading to a limited understanding of their spatial distribution in China.Insufficient geospatial datasets of SWBs limit the accurate assessments of resource utilization and fluxes of biogenic elements in both aquatic and terrestrial ecosystems.To address this,in this study,we applied a convolutional neural network and a visual interpretation approach to extract SWBs from high-resolution satellite images from Google Earth.The spatial distribution of SWBs in China was mapped,and drivers of the spatial pattern of SWBs were also identified.As a result,a total of 5.18 million water bodies with a surface area larger than 0.1 ha,including ponds,lakes,and reservoirs,were identified.These water bodies(>0.1 ha)cover approximately 179300 km^(2),which is approximately 1.8%of the land area in China.In addition,the combined shoreline length of the water bodies was approximately 2157400 km.Of these water bodies,96.85%were SWBs,accounting for 17.85%of the total water area and 76.4% of the total shoreline length.Precipitation,terrain,and human activity cumulatively explained 45% of the variance in SWB distribution,with precipitation being the strongest climatic explanatory factor.Our results provide important data for determining the roles of SWBs in biogeochemical cycles,habitat protection,and hydrological cycles.
基金This project is supported by National Natural Science Foundation of China(No.59975031).
文摘The flow characteristics and cavitation effects of water passing throughsmall sharp-edged cylindrical orifices and valves of different shapes in water hydraulics areinvestigated. The test results using orifices with different aspect ratios and different diametersshow that the flow coefficients in the case of non-cavitating flow are larger than that of flow inthe case of cavitation occurrence. The flow coefficients of flow with cavitation initially decreaseas Reynolds number increases and ultimately tend to be of constant values close to contractioncoefficient. Large aspect ratio has an effect of suppressing cavitation. The experimental resultsabout disc valves illustrate that the valves with sharp edge at large opening are less affected bycavitation than that at small opening. Throttle with triangle notch has better anti-cavitationability than that with square notch. The flowrate of the throttle with square notch is significantlyaffected by the flow direction or the flow passage shape.
基金supported by grants from the National Nature Science Foundation of China(31501986)Fundamental Research Funds for Central Universities(KJQN201611 and KYDS201809)Earmarked Fund for Jiangsu Agricultural Industry Technology System(SXGC[2018]287)
文摘Background: Following the intake of Fusarium mycotoxin-contaminated feed,small intestines may be exposed to high levels of toxic substances that can potentially damage intestinal functions in livestock.It is well known that Fusarium mycotoxins will lead a breakdown of the normally impeccable epithelial barrier,resulting in the development of a "leaky" gut.H2 administration with different methods has been proved definitely potentials to prevent serious intestinal diseases.The goal of this study is to investigate the roles of lactulose(LAC) and hydrogenrich water(HRW) in preventing intestinal dysfunction in piglets fed Fusarium mycotoxin-contaminated feed.Methods: A total of 24 female piglets were evenly assigned to 4 groups: negative control(NC) group,mycotoxincontaminated(MC) feed group,MC feed with LAC treatment(MC + LAC),and MC feed with HRW treatment(MC +HRW),respectively.Piglets in the NC group were fed uncontaminated control diet,while remaining piglets were fed Fusarium mycotoxin-contaminated diet.For the NC and MC groups,10 mL/kg body weight(BW) of hydrogen-free water(HFW) was orally administrated to piglets twice daily;while in the MC + LAC and MC + HRW groups,piglets were treated with the same dose of LAC solution(500 mg/kg BW) and HRW twice daily,respectively.On d 25,serum was collected and used for biochemical analysis.Intestinal tissues were sampled for morphological examination as well as relative genes and protein expression analysis.Results: Our data showed that Fusarium mycotoxins induced higher serum diamine oxidase(DAO) activities(P < 0.05),D-lactic acid levels(P < 0.01),and endotoxin status(P < 0.01),lower villus height(P < 0.01) and ratio of villus height to crypt depth(P < 0.05) in small intestine,greater apoptosis index and higher mRNA expression related to tight junctions(P < 0.05).In addition,the distribution and down-regulation of claudin-3(CLDN3) protein in the small intestinal was also observed.As expected,oral administrations of HRW and LAC were found to remarkably provide beneficial effects against Fusarium mycotoxin-induced apoptosis and intestinal leaking.Moreover,either HRW or LAC treatments were also revealed to prevent abnormal intestinal morphological changes,disintegrate tight junctions,and restore the expression and distribution of CLDN3 protein in the small intestinal mucosal layer in female piglets that were fed Fusarium mycotoxins contaminated diet.Conclusions: Our data suggest that orally administrations of HRW and LAC result in less Fusarium mycotoxininduced apoptosis and leak in the small intestine.Either HRW or LAC treatments could prevent the abnormal changes of intestinal morphology and molecular response of tight junctions as well as restore the distribution and expression of CLDN3 protein of small intestinal mucosa layer in female piglets that were fed Fusarium mycotoxins contaminated diet.
文摘Taking the water ecosystem of Small Xingkai Lake as research object,through the survey and analysis of aquatic organism indicators,this paper established an ecosystem integrity evaluation system with the biological integrity as the criterion layer. Using the index of biological integrity and comprehensive health index,it evaluated the health status of water ecosystem of Small Xingkai Lake.
基金Supported by Scientific Research Planning Project of Beibei District,Chongqing City(2017-18)
文摘Based on the health risk assessment model of water quality recommended by United States Environmental Protection Agency (USEPA), the health risk of five centralized drinking water sources in small towns of Beibei District, Chongqing City was evaluated. The results showed that the risk of health hazard of chemical carcinogen arsenic did not exceed the acceptable level recommended by the International Commission on Radiological Protection (ICRP)(5.0×10 -5 a -1 ), but was still at the same order of magnitude as the recommended value of ICRP. The risk of the highest health hazard was 127 times higher than the maximum acceptable level recommended by Sweden EPA and Holland EPA (1.0×10 -6 a -1 ). The health risk of As in genetic toxic substances at monitoring points A, B, and C accounted for 99.99% of the total risk, showing that As was the main pollutant that posed the health risk, so priority should be given to the prevention and control of As pollution in the centralized drinking water sources in Chongqing towns.
基金funded by the Ministry of Agriculture and Rural Affairs of the P.R.China under Project of Fishery Exploration in 2017(No.D-8006-17-0138)
文摘The relationship between the spatiotemporal distribution of three dominant small pelagic fishes,including chub mackerel(Scomber japonicus),horse mackerel(Trachurus trecae)and round sardinella(Sardinella aurita),and the environmental factors in Mauritanian waters were analyzed by using 4 years of logbook data of commercial purse seine fisheries to improve the efficiency of fishery and management of sustainable exploitation.A Tweedie-generalized additive model(GAM)of 8-day average catches and the monthly geostatistical analysis of daily catches were used in this study to analyze the influence of environmental factors on catch per unit of effort(CPUEs)and to map the spatial distribution of three mixed dominant small pelagic fishes,respectively.A 10'×10' grid was used,and environmental factors were processed from remote sensing,including 8-day average sea surface temperature(SST),the nearest distance between SST fronts and CPUE position(Df),chlorophyll-a(Chl-a)concentration,salinity,and eddy kinetic energy.Results showed that 1)the distribution of three dominant small pelagic fishes might be related to the intensity of upwelling in Mauritanian waters;2)oceanic fronts might play a key role in the ecology of chub mackerel,horse mackerel,and round sardinella;3)Chl-a concentration might be associated with the feeding grounds of chub mackerel;4)the target species distribution appeared sensitive to gradient changes in the amount of salinity;5)three zones(northern,central,and southern)with variable abundances were delineated;and 6)a high concentration of the center of gravity in the central zone might be related to the strong upwelling of nutrient-rich waters.This study can provide new insights to enhance the fishery efficiency and sustainable exploitation management of purse seiners in certain area off Mauritania.
文摘In karst area water deficit is one of the main factors constraining sustainable economic development. In 1979 the comprehensive karstic observational field station was set up in Houzhai drainage basin located,\ in Puding county of Guizhou Province, which can represent most of the small karst drainage basins on the dividing line of the Guizhou Plateau. Geomorphology, water resources and water chemistry were investigated and observed. Based on comparisons of water supply with water demand and analysis of the main problems in water exploitation and utilization. it is found out that the water deficiency was not directly caused by the scarcity of natural water resources. The true reason is the insufficient capacity of water supply caused by the dismatch of the water and soil water resources which can be dealt with by building more irrigation works. Some solutions such as to build scientific basis for water exploitation and utilization and sustainable economic development in karst drainage basins on dividing line of the Guizhou Plateau.
文摘针对水面目标检测中的噪声干扰和小目标的漏检问题,提出一种改进YOLOv8的水面小目标检测算法YOLOv8-WSSOD(YOLOv8-water surface small object detection).首先,为降低水面复杂环境在主干网络下采样过程中产生的噪声干扰,提出基于BiFormer双层路由注意力机制构建的C2fBF(C2f-BiFormer)模块,在特征提取过程中保留细粒度的上下文特征信息;其次,针对水面小目标的漏检问题,新增一个更小的检测头,提升网络对小目标的感知力,并在Neck端引入GSConv和Slim-neck,减轻模型复杂度并保持精度;最后,使用MPDIoU损失函数解决CIoU损失函数的局限性,以提高模型检测准确率.实验结果表明,相较于原始YOLOv8算法,该算法在水面小目标上平均准确率mAP@0.5提升了4.6%,mAP@0.5:0.95提升了2.2%,并且改进后的算法检测速度达到86f/s,能有效实现对水面小目标快速、准确的检测.