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Post-disaster medical rescue strategy in tropical regions 被引量:3
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作者 Xiang-hui Li Shi-ke Hou +2 位作者 Jing-chen Zheng Hao-jun Fan Jian-qi Song 《World Journal of Emergency Medicine》 CAS 2012年第1期23-28,共6页
BACKGROUND:Earthquakes,floods,droughts,storms,mudslides,landslides,and forest wild fires are serious threats to human lives and properties.The present study aimed to study the environmental characteristics and pathoge... BACKGROUND:Earthquakes,floods,droughts,storms,mudslides,landslides,and forest wild fires are serious threats to human lives and properties.The present study aimed to study the environmental characteristics and pathogenic traits,recapitulate experiences,and augment applications of medical reliefs in tropical regions.METHODS:Analysis was made on work and projects of emergency medical rescue,based on information and data collected from 3 emergency medical rescue missions of China International Search and Rescue Team to overseas earthquakes and tsunamis aftermaths in tropical disaster regions — Indonesia-Aceh,Indonesia-Yogyakarta,and Haiti-Port au Prince.RESULTS:Shock,infection and heat stroke were frequently encountered in addition to outbreaks of infectious diseases,skin diseases,and diarrhea during post-disaster emergency medical rescue in tropical regions.CONCLUSIONS:High temperature,high humidity,and proliferation of microorganisms and parasites are the characteristics of tropical climate that impose strict requirements on the preparation of rescue work including selective team members suitable for a particular rescue mission and the provisioning of medical equipment and life support materials.The overseas rescue mission itself needs a scientific,efficient,simple workflow for providing efficient emergency medical assistance.Since shock and infection are major tasks in post-disaster treatment of severely injured victims in tropical regions,the prevention and diagnosis of hyperthermia,insect-borne infectious diseases,tropic skin diseases,infectious diarrhea,and pest harms of disaster victims and rescue team staff should be emphasized during the rescue operations. 展开更多
关键词 DISASTERS tropical regions EARTHQUAKE Emergency medical rescue
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Follow-up study on ThinPrep cytology test-positive patients in tropical regions
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作者 Yun-Chun Chen Chong-Nan Liang +3 位作者 Xiang-Feng Wang Min-Fa Wang Xu-Ning Huang Jian-Dong Hu 《World Journal of Clinical Cases》 SCIE 2022年第34期12543-12550,共8页
BACKGROUND As shown in the statistics from the World Health Organization,it is estimated that approximately 75000 new cases of cervical cancer occur every year in China.In 2008,33000 people died of cervical cancer in ... BACKGROUND As shown in the statistics from the World Health Organization,it is estimated that approximately 75000 new cases of cervical cancer occur every year in China.In 2008,33000 people died of cervical cancer in China.It is proven that most women are at risk of cervical cancer.The progression from human papillomavirus(HPV)infection to cervical cancer can be several years or decades,which offers a unique opportunity to prevent cancer.AIM To observe the changes in ThinPrep cytology tests(TCT)and HPV infection in patients who were detected to be positive via TCT screening of cervical cancer and further explore the biopsy results.METHODS This paper performed a follow-up study on 206 cervical cancer screening-positive patients of 12231 total cases from our previous research.We conducted an observational study on the TCT results based on the interpretation of The Bethesda System.RESULTS Over a 5-year period,10 cases received consistent follow-up.The proportions of cases in which glandular epithelial lesions were detected increased over the follow-up period.The differences between the years were statistically significant(P<0.01).Over the 5 years,the proportion of patients whose squamous epithelial lesions transformed into glandular epithelial lesions increased yearly.Annual positive rates of HPV infection were:year 1,73%(24/33);year 2,43%(6/14);year 3,36%(9/25);year 4,50%(9/18);and year 5,25%(6/24).The positive detection rate after biopsy over a 9-year period was 29%.CONCLUSION The follow-up study for 5 years to 9 years revealed a tendency to change from squamous epithelial lesions to glandular epithelial lesions and an improvement of the disease(which had not been reported previously).The HPV test indicated a high negative conversion ratio of the viral infection.However,the follow-up cases were not found to have persistent infection of high-risk HPV.Therefore,early intervention of cervical cancer screening is necessary.Low re-examination compliance,patient education,and preventive measures should be enhanced. 展开更多
关键词 Cervical cancer ThinPrep cytology test screening Human papillomavirus Follow-up study SCREENING tropical regions
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Weather Yield Model for the Semi Tropical Region (Pakistan)
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作者 Syed Faizan Haider K.H.Asif Amjad Hussain Gilani 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1992年第3期367-372,共6页
Weather models are essential tools for checking of the effect of the weather elements in terms of their effect on the production of the crop. This research is an attempt to see the effect of only two variables i.e., t... Weather models are essential tools for checking of the effect of the weather elements in terms of their effect on the production of the crop. This research is an attempt to see the effect of only two variables i.e., temperature and rainfall for the division Faisalabad (semitropical region of Pakistan).The model fitted is of the linear form:the values of a,b, c have been found. The expected yield has been calculated by using the aridity indices (X1 and X2 ) and the result in the form of coefficient of determination R2 has been found equal to 0.166. The significance of the regression coefficient has been tested, which shows that the contribution to the yield from aridity index at germination and that at ripening is significant.The wheat yields are the results of a wide variety of variables, most of which show varying degree of relationship with one another, some positive and some negative in terms of output. These variables may be technology, fertilizers, pesticides, epidemics, kinds of seeds used, market price of crop and the area under cultivation etc, which can be the source of variation in the wheat yield. Since rainfall during germination and temperature at the ripening periods are the necessary factors for the yield of wheat, for this purpose these parameters have been studied in order to their contribution. 展开更多
关键词 Weather Yield Model for the Semi tropical region Pakistan
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Investigation of the Effects of Glazed Balconies uponThermal Comfort in Hot Tropical Region
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作者 Érica Coelho Pagel Edna Aparecida Nico Rodrigues +4 位作者 Cristina Engel de Alvarez Neyval Costa Reis Júnior Bruna Perovano Sirtuli Filipe Galina Costalonga Jordana BernabéCoelho 《Journal of Civil Engineering and Architecture》 2019年第12期762-779,共18页
The balcony is responsible to a series of effects on the environmental behavior of a building,mainly in relation of thermal comfort and air distribution to their indoor spaces.Currently a very common practice in sever... The balcony is responsible to a series of effects on the environmental behavior of a building,mainly in relation of thermal comfort and air distribution to their indoor spaces.Currently a very common practice in several metropolitan areas is the closing with retractable glass panels in balcony openings.This work analyzed the effects of glazed balconies upon thermal comfort in a hot tropical region.Environmental parameters were carried out in a flat alternating the conditions of retractable glass panels to balconies.Thermal simulations were performed considering closing or not the glass door that divides the balcony room;the building material used on the balcony sill;and the use of curtains or shading devices.The results show the maximum mean hourly temperatures recorded on the balcony during the period when the retractable glass panels were closed,reaching peaks between 31.7 and 39.2°C,above the comfort range recommended by ASHRAE 55.All situations simulated show the thermal discomfort prevails in the use of the closed glass panels reaching DhTD of 94.55°C/day.Thus,this practice of using most of the closed retractable glass panels in the balconies presents disadvantages and inefficiencies especially in hot and humid tropical climate regions. 展开更多
关键词 Glazed balconies thermal comfort hot tropical region.
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INSTABILITY OF THE OCEANIC WAVES IN THE TROPICAL REGION 被引量:1
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作者 季振刚 巢纪平 《Acta meteorologica Sinica》 SCIE 1990年第2期135-145,共11页
In this paper, the effects of the large-scale mean sea temperature fields of the tropical ocean and the zonal current field (southern equatorial current) have been comprehensively entered in consideration on the basis... In this paper, the effects of the large-scale mean sea temperature fields of the tropical ocean and the zonal current field (southern equatorial current) have been comprehensively entered in consideration on the basis of Chao and Ji (1985), and Ji and Chao (1986), the equatorial oceanic waves of the tropical ocean have been discussed by use of linearized primitive equations, then, the significant influence of the climatic back- ground fields of the tropical ocean upon the oceanic waves of this region has been further testified. When very cold water appears in the tropical region, and the southern equatorial current is also relatively strong, the effect of the Rossby wave weakens, as a consequence, there are substitutive slow waves (i.e. thermal waves) which travel in opposite direction (eastward) to the Rossby wave. The characteristics of the slow wave are similar to those of Rossby waves, only the travelling direction is opposite. Under a certain environ- mental background field, the slow wave and the modified Rossby wave may be instable. With this conclu- sion, the mechanism of the occurrence, development and propagation of El Nino events has been studied. It is pointed out that the opposite travelling direction of the thermal wave and Rossby wave will bring re- pectively into action under different marine environmental background fields. The physical causes for that the abnormal warm water inclines to occur along the South American coast have also been explored in this paper. 展开更多
关键词 SSTA INSTABILITY OF THE OCEANIC WAVES IN THE tropical region Nino
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A New Algorithm for a Condenser Design for Large-Scale Nuclear Power Plants in Tropical Region
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作者 KHAN Abid Hossain ISLAM Md.Shafiqul 《Journal of Thermal Science》 SCIE EI CAS CSCD 2020年第5期1370-1389,共20页
This work presents a new velocity search algorithm for designing a condenser of a 1200 MWe large-scale nuclear power plant situated in tropical region.For this,the condenser pressure was considered in the range of 7.5... This work presents a new velocity search algorithm for designing a condenser of a 1200 MWe large-scale nuclear power plant situated in tropical region.For this,the condenser pressure was considered in the range of 7.5-15 kPa while its tube inner diameter was taken as 28 mm with 1 mm tube wall thickness.Both longitudinal and transverse condensers with multiple shell tanks and varied shell tank lengths from 8-14 m have been considered in this work.Three different tertiary coolant temperature rises were chosen as 4°C,8°C and 12°C by considering tropical region average reservoir water temperature range of 28°C to 32°C during summer.Velocity of tertiary coolant was kept within 0.75-1.5 m/s to ensure sufficient turbulence to avoid erosion-corrosion of the tubes.Numerical simulation has been employed to obtain tube-side pressure drop and convection heat transfer coefficient directly from tertiary coolant inlet velocity using κ-ω turbulent flow model.A new iterative“Velocity-search algorithm”has been developed that focuses on finding the correct tertiary coolant velocity instead of overall heat transfer coefficient.Results revealed that velocity-search algorithm yielded very close to the important physical and thermal parameters of condenser compared to the existing design data in large scale nuclear power plants.Velocity-search algorithm has given less number of condenser design physical parameters that meets the velocity acceptance criteria for longitudinal condenser compared to the transverse condenser.Finally,velocity-search algorithm is found to be more reliable,robust,and consistent for condenser design compared to the conventional design algorithm used in Log-Mean Temperature Difference method. 展开更多
关键词 nuclear power plant vacuum condenser velocity-search algorithm tropical region
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Simulation and Analysis about the Effects of Geopotential Height Anomaly in Tropical and Subtropical Region on Droughts or Floods in the Yangtze River Valley and North China
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作者 黄燕燕 钱永甫 万齐林 《Acta meteorologica Sinica》 SCIE 2006年第4期426-436,共11页
Previous study comes to the conclusion: based on the anomalies of the South Asian high (SAH), 100-hPa geopotential height, and 100-hPa circulation over tropical and subtropical regions, we can predict precipitation... Previous study comes to the conclusion: based on the anomalies of the South Asian high (SAH), 100-hPa geopotential height, and 100-hPa circulation over tropical and subtropical regions, we can predict precipitation anomaly in the Yangtze River Valley and North China. To test its validity, a series of experiments have been designed and operated, which include controlled experiment, sensitivity experiment (which has added anomalies into 100-hPa geopotential height and wind field), and four-composite experiments. Experiments based on the composed initial field such as EPR-CF, EPR-CD, EPR-HF, and EPR-HD, can reproduce the floods or droughts in the Yangtze River Valley and North China. It suggests that anomalies of the SAH, 100- hPa geopotential height, and circulation over tropical and subtropical regions may probably imply summer precipitation anomalies in the two regions. Sensitivity experiment results show that anomalies of the SAH, 100-hPa geopotential height, and southwest flow in the previous period is a signal of droughts or floods for the following summer in the Yangtze River Valley and North China. And it is also one of the factors that have impact on summer precipitation anomaly in the two regions. Positive anomaly of 100-hPa geopotential height and the anomalous intensifying of the SAH and southwest flow will induce floods in the Yangtze River Valley and droughts in North China; while negative anomaly of 100-hPa geopotential height and anomalous weakening of the SAH and southwest flow will induce droughts in the Yangtze River Valley and floods in North China. 展开更多
关键词 geopotential height anomalies tropical and subtropical regions South Asian high (SAH) droughts or floods in the Yangtze River Valley droughts or floods in North China simulation and analysis
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Climatological Features of the Global Tropical Subsidence Region Based on Satellite Observations 被引量:4
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作者 蒋尚城 叶谦 +1 位作者 杨喜峰 安刚 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2000年第3期391-402,共12页
Consisting of subtropical highs and tropical buffer zone, the global tropical subsidence region is the subsidence branches of Hadley cell. Walker circulation and monsoon circulation which are important components of t... Consisting of subtropical highs and tropical buffer zone, the global tropical subsidence region is the subsidence branches of Hadley cell. Walker circulation and monsoon circulation which are important components of the global general circulation. This region is closely connected with Asian monsoon. Based on long-term satellite observations of OLR (Outgoing Longwave Radiation) and HIRS-Tbl2 (the bright temperature from High-resolution Infra-red Radiation Sounder Channel 12 (6.7 Μm)), the climatological features over the global tropical subsidence region are studied in this paper and the main findings are as follows: Key words Satellite observation - OLR - HIRS-Tb12 - Tropical subsidence region - Monsoon This project was supported by the State Key Project of the SCSME and the National NSF No. 49875016. 展开更多
关键词 Satellite observation OLR HIRS-Tb12 tropical subsidence region MONSOON
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Plant Landscape Design Language of Small Street Parks in Tropical Coastal Regions:A Case Study of Zhanjiang City 被引量:1
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作者 HUANG Yanna LIU Jinfang 《Journal of Landscape Research》 2017年第2期63-66,共4页
Small urban street parks play an irreplaceable role in protecting ecological environment of cities and beautifying living spaces of citizens, in these parks plant is an essential landscaping element that can not only ... Small urban street parks play an irreplaceable role in protecting ecological environment of cities and beautifying living spaces of citizens, in these parks plant is an essential landscaping element that can not only improve environmental quality, but also provide visual enjoyment for viewers. There are many small street parks in Zhanjiang City, however, plant landscapes in such parks lack in regional characteristics because of blind copy and random planting. By analyzing plant landscapes in typical street parks in Zhanjiang, and borrowing the theoretical research framework of linguistics, this paper concluded the vocabulary, sentence,chapter and grammatical rules of plant landscape design, in order to explore new methods for the plant landscape design of small parks in tropical coastal regions. 展开更多
关键词 Landscape architecture Plant landscape Small street park Landscape design language tropical coastal region
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Carbon stocks in a highly fragmented landscape with seasonally dry tropical forest in the Neotropics
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作者 N.Mesa-Sierra J.Laborde +1 位作者 R.Chaplin-Kramer F.Escobar 《Forest Ecosystems》 SCIE CSCD 2022年第2期168-177,共10页
Background:Global modeling of carbon storage and sequestration often mischaracterizes unique ecosystems such as the seasonally dry tropical forest of the central region of the Gulf of Mexico,because species diversity ... Background:Global modeling of carbon storage and sequestration often mischaracterizes unique ecosystems such as the seasonally dry tropical forest of the central region of the Gulf of Mexico,because species diversity is usually underestimated,as is their carbon content.In this study,aboveground and soil carbon stocks were estimated to determine the climate mitigation potential of this highly degraded landscape(<25%of forest cover).Results:Tree species in the study area had carbon content values that were 30%–40%higher than the standard value proposed by the IPCC(i.e.,50%).Tropical oak forest in the region,despite its restricted distribution and low species richness,accounted for the highest mean carbon stocks per unit area.The main factors driving spatial variability in carbon stocks were:maximum precipitation,soil organic matter,clay and silt content.No strong relationship was found between aboveground carbon stocks and soil organic carbon in the study area.Quanti-fication of carbon stocks is an important consideration in the assessment of the conservation value of remnants of native vegetation in human-modified landscapes.Conclusions:This study demonstrates the importance of the highly fragmented tropical dry regions of the Neo-tropics in maintaining landscape functionality and providing key ecosystem services such as carbon sequestration.Our results also highlight how crucial field-based studies are for strengthening the accuracy of global models.Furthermore,this approach reveals the real contribution of ecosystems that are not commonly taken into account in the mitigation of climate change effects. 展开更多
关键词 Seasonally dry tropical region Ecosystem services Carbon sequestration Human modified landscapes Climate change mitigation
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Does cryptic dichromatism exist in the Saffron Finch(Sicalis flaveola)?Colorimetric variables and the avian visual model
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作者 Lorena Cruz-Bernate Camilo Espinosa-Bravo Hector Fabio Rivera-Gutierrez 《Avian Research》 SCIE CSCD 2023年第3期405-415,共11页
Sexual dichromatism,a particular type of sexual dimorphism,occurs in several species and has been associated with sexual selection.In some cases,the differences are so small that they are imperceptible to humans,but p... Sexual dichromatism,a particular type of sexual dimorphism,occurs in several species and has been associated with sexual selection.In some cases,the differences are so small that they are imperceptible to humans,but possibly detected by birds.The objective measurement of color with spectrophotometers and detailed analyses according to the perception ability of the avian eye have revealed that some species that were once considered to be monochromatic,are in fact dichromatic and able to perceive these differences.In the tropics,the Saffron Finch(Sicalis flaveola) does not present marked sexual dimorphism in coloration,which makes studies in behavioral ecology,natural history and population dynamics difficult.To assess whether there is dichromatism in the species,the reflectance(between 300 and 700 nm) of ten body regions was measured in 196 wild adults in Cali-Colombia.Sex was determined using the CHD1 gene on the sex chromosomes.Reflectance spectra were analyzed using:colorimetric variables and the avian visual model.We found that reflectance shows a bimodal curve in all body regions,except the crown.Males presented higher reflectance at long wavelengths,while for females this occurred in ultraviolet wavelengths.For the visual model,we found that there are significant intrasexual differences;however only in crown coloration is there a possible perceived difference between sexes.We conclude that in the Saffron Finch there are color differences between the sexes in all regions considering the physical phenomenon(reflectance),but in general,when evaluating color perception(avian visual model),there are no differences between the sexes in most of the body regions.The intrasexual differences are significant,indicating the possibility of these being signals that influence social interactions in the species. 展开更多
关键词 Carotenoids Color discrimination Colombia Intrasexual signals Social selection Tanagers tropical region
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Population occurrence of the fall armyworm,Spodoptera frugiperda(Lepidoptera:Noctuidae),in the winter season of China 被引量:10
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作者 YANG Xian-ming SONG Yi-fei +7 位作者 SUN Xiao-xu SHEN Xiu-jing WU Qiu-lin ZHANG Hao-wen ZHANG Dan-dan ZHAO Sheng-yuan LIANG Ge-mei WU Kong-ming 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2021年第3期772-782,共11页
Fall armyworm(FAW),Spodoptera frugiperda(J.E.Smith),has become an important pest in Chinese agricultural systems since its invasion on 11 December 2018.After its establishment,FAW months in the year-round breeding reg... Fall armyworm(FAW),Spodoptera frugiperda(J.E.Smith),has become an important pest in Chinese agricultural systems since its invasion on 11 December 2018.After its establishment,FAW months in the year-round breeding region have become the main source population migrating to other areas in China.Field investigations were conducted in tropical and subtropical regions to improve understanding of its year-round breeding area in China.The results showed that FAW larval density was significantly correlated with the seasonal temperature of the location surveyed.The FAW larvae maintained a high density in the tropical area and were frequently found in sites of the south subtropical region,but were absent from the north subtropical region and the northern part of the central subtropical region.These results indicated that FAW can reproduce annually in the tropical and south subtropical regions of China,including Hainan,Taiwan and the southern area of Fujian,Guangdong,Guangxi,Guizhou,and Yunnan.Hence,great effort should be made to monitor and control FAW in the year-round breeding region to suppress the population density of this area and to reduce migration of moths into northern parts of China.This study clarifies the occurrence area of the pest in winter in China and provides much valuable information for its population forecasting and management. 展开更多
关键词 fall armyworm temperature year-round breeding region tropical region subtropical region
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Activity Recording of Free-Ranging Tri-spine Horseshoe Crabs in the Southeastern Coast of Sabah,Borneo
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作者 WATANABE Shinichi NELSON Bryan Raveen +1 位作者 MANCA Azwarfarid MOHAMAD Faridah 《Journal of Ocean University of China》 SCIE CAS CSCD 2022年第3期549-556,共8页
In Inderasabah(southeast Sabah),tri-spine horseshoe crab Tachypleus tridentatus was observed for their locomotion activity using data loggers from September to November in 2015.A female with acceleration and depth-tem... In Inderasabah(southeast Sabah),tri-spine horseshoe crab Tachypleus tridentatus was observed for their locomotion activity using data loggers from September to November in 2015.A female with acceleration and depth-temperature loggers and five males with acceleration loggers were recaptured between 10 and 49 days after their release.From the record of 194 activity days that involve all six T.tridentatus,four horseshoe crabs,including the female,were active throughout the 24.0 h cycle,whereas the activity of the remaining two males was consistent with the 12.4 h cycle.Using the 40-day recording,three horseshoe crabs,including the female,were primarily active around the new moon and full moon,but they were dormant around the first and third quarter moon days.The female spent much time in shallow shores(depth<0.3 m)during the new moon and full moon.This result indicated that the female attempted to spawn in a minimum of three spring tide periods while lingering in the vicinity.Meanwhile,after spawning,the female spent time foraging in shallow water(depth 0.3–18 m).As for the two male individuals,their activity was consistent with semi-lunar periodicity.Therefore,both of them were in amplexus.In addition,a solitary male individual was active only during the first and third quarter moon days.Through activity recording,all the T.tridentatus in Inderasabah was active during daytime and nighttime.This result was contrary to T.tridentatus activity cycles in western Japan,where the species was found to be primarily nocturnal.Perhaps,the regional differences in activity cycles for T.tridentatus were related to their population adaptation toward water temperature,depth,and prey-searching periods. 展开更多
关键词 acceleration logger activity cycle depth-temperature logger foraging behavior spawning behavior tropical region Tachypleus tridentatus
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Optimization of Organic Mulches Thickness Improves Soil Moisture Retention under Controlled Conditions
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作者 Jiayi Zhang Guohua Fu +3 位作者 Zhiyang Jin Lihang Chi Guocheng Xu Daran Yue 《Phyton-International Journal of Experimental Botany》 SCIE 2022年第4期841-857,共17页
Organic mulch can improve the moisture,chemical composition,dust,and dust suppression of soil,and beautify the environment.In view of the rapid evaporation rate and serious loss of soil water in tropical areas,this pa... Organic mulch can improve the moisture,chemical composition,dust,and dust suppression of soil,and beautify the environment.In view of the rapid evaporation rate and serious loss of soil water in tropical areas,this paper explored the effect of organic mulch materials with different thickness on the increase of soil water retention rate and the improvement of soil water loss caused by evaporation.Rubberwood sawdust(RWS),rubberwood bark(RWB),coconut fiber(CF),and Mulch(MC)were selected as the mulching materials.Field experiment and laboratory experiment were performed,and soil-moisture content and temperature were continuously monitored.However,from the daily measurement of water content at constant conditions(29℃±0.2℃,74%±1%air RH)in the laboratory experiment,the results of variance analysis(ANOVA)showed that there was no significant difference between the soil-water content of covered samples and bare soil(P>0.05).In the field experiments,the analysis of variance indicated significant differences in the soil-moisture content owing to the effect of the covering material(P<0.01).Mulching increased the soil-moisture content with smaller fluctuations in the deep soil compared with bare soil.The most stable soil-moisture content were achieved by RWS,RWB,CF,and MC,with thicknesses of 5,3,7,and 5 cm,respectively,compared with bare soil,and the average water contents of the 0-40 cm soil layer was 0.58%,0.01%,0.82%,and 0.93%,respectively.Vertically,the intensity of the change in soil moisture decreased gradually with increasing depth,and was more stable than that of bare soil and other treatments.Among them,the difference in water content between the adjacent gradient soil layers(the soil layers are graded every 10 cm in depth)M_(3-7)(0.011±0.004)was the smallest.It can be concluded that CF mulching materials with a thickness of 7 cm would be preferable when selecting mulching materials for controlling soil moisture in tropical cities. 展开更多
关键词 Organic mulch soil moisture content humid tropical region soil improvement
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The Influence of Climate Variability on Holoplanktonic Polychaetes Populations of Ocean Sector of the Colombian Pacific Basin
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作者 José Manuel Gutiérrez-Salcedo Adibe Cárdenas-Oliva Néstor H. Campos 《Open Journal of Ecology》 2021年第4期317-343,共27页
Studies of holoplanktonic polychaetes in the Tropical Eastern Pacific have focused on their systematics and distribution however, population responses related to climate variability are non-existent. Therefore, the pr... Studies of holoplanktonic polychaetes in the Tropical Eastern Pacific have focused on their systematics and distribution however, population responses related to climate variability are non-existent. Therefore, the present work described for the first time the influence of the climatic variability 2004-2012 on the holoplanktonic polychaetes populations, as well as their relationship to environmental variables. Species of the Alciopidae, Lopadorrhynchidae and Iospilidae families were identified from 85 samples collected in the Pacific Basin of Colombia, contrasting them with the presence of ENSO, and correlating them with the environmental variables of temperature, salinity and chlorophyll-<em>α</em> concentration. Of the 14 species identified, only <em>Lopadorrhynchus</em> cf. <em>henseni</em> and <em>L</em>. cf. <em>brevis</em> increased their densities under El Ni<span style="white-space:nowrap;"><span style="white-space:nowrap;">&#241;</span></span>o and correlated positively with temperature. <em>Rhynchonereella</em> cf. <em>petersii</em> correlated negatively with temperature;while <em>R</em>. cf. <em>gracilis</em> and <em>Pelagobia</em> cf. <em>longicirrata</em> were positively correlated with chlorophyll-<em>α</em> concentration and salinity, respectively. Additionally, with the first description of the environmental ranges of the 14 species identified for the Colombian Pacific basin, it was found that the most commons species presented broader environmental ranges. The results from the current research are consistent with previous studies in other regions of the Pacific and latitudes. The responses of the organisms suggest trophic and mobility trends that were not known for tropical holoplanktonic polychaete species. 展开更多
关键词 Temperature CHLOROPHYLL Oceanic Province tropical region El Niño Southern Oscillation—ENOS
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Study about Top-Down and Bottom-Up Controls in Regulating the Phytoplankton Biomass in a Eutrophic Reservoir in Northeastern Brazil
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作者 Juliana dos Santos Severiano Ariadne do Nascimento Moura +1 位作者 Enaide Marinho de Melo Magalhaes Viviane Lucia dos Santos Almeida 《Journal of Water Resource and Protection》 2012年第8期616-621,共6页
This study aims to analyze the effects of nutrients and predation by zooplankton on phytoplankton biomass (chlorophyll a) in a eutrophic reservoir in Brazil (Apipucos Reservoir, State of Pernambuco), through experimen... This study aims to analyze the effects of nutrients and predation by zooplankton on phytoplankton biomass (chlorophyll a) in a eutrophic reservoir in Brazil (Apipucos Reservoir, State of Pernambuco), through experiments in microcosms. For this, samples of water were placed in 1 L Erlenmeyer flasks and kept for seven days. Treatments included the addition of nutrients (nitrogen combined with phosphorus and isolated additions of nitrogen and phosphorus), with presence and absence of zooplankton and a control which contained the reservoir water without any manipulation. The addition of nutrients did not stimulate phytoplankton growth. However, zooplankton significantly decreased phytoplankton biomass in the treatments it was added to (p < 0.05). The results of this study showed that for the reservoir studied, predation by zooplankton is the most significant factor in the regulation of phytoplankton, contradicting several studies which show that phytoplankton biomass is more strongly controlled by nutrients (bottom-up control) than by predation (top-down control). 展开更多
关键词 Chlorophyll α NUTRIENTS ZOOPLANKTON tropical regions
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Endophytic Mycodiversity of Sacred Tree-Couroupita guianensis Aubl.
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作者 Velmurugan R Ramesh V +2 位作者 Meenatchi A Bagyalakshmi Rajendran A 《Studies in Fungi》 2017年第1期119-129,共11页
In the present study,a total of 142 fungal strains were isolated from 180 samples of the leaf,stem and bark tissues of sacred tree Couroupita guianensis from an unusual semi-arid tropical region.The tissues of the sam... In the present study,a total of 142 fungal strains were isolated from 180 samples of the leaf,stem and bark tissues of sacred tree Couroupita guianensis from an unusual semi-arid tropical region.The tissues of the samples were grown in potato dextrose agar(PDA)medium and the endophytic mycoflora were identified based on the morphological characteristics.Among all the strains,130 were fertile,which belong to 11 species and 12 sterile morpho species.The relative frequency of isolated individual endophytic fungal group consists of hyphomycetes(41.5%),coelomycetes(32.4%),ascomycetes(13.4%),zygomycetes(4.2%)and sterile fungi(8.5%).Among the fungal isolates,Scytalidium acidophilum and Mycosphaerella sp.were recorded as the most dominant fungal isolates in the leaf tissues,Cladosporium cladosporioides and Colletotrichum falcatum were observed as the dominant endophytic fungal isolates in the stem tissues and Botryodiplodia theobromae was found to be predominant species in bark tissues of C.guianensis.The species of Colletotrichum were found only in stem tissues.Therefore,the endophytic mycodiversity were high and abundant and they were distinctly associated with host plant.All statistical analyses confirmed that leaf tissues contained more endophytes than the stem and bark while Colletotrichum exhibited organ specificity.The present study revealed that the sacred tree C.guianensis is one of the ecological niches for sheltering endophytic mycoflora eventhough in harsh climatic conditions. 展开更多
关键词 COLLETOTRICHUM PDA organ specificity semi-arid region tropical region
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Factors Affecting Adoption of Improved Rice Varieties among Rural Farm Households in Central Nepal 被引量:4
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作者 Raju GHIMIRE HUANG Wen-chi Rudra Bahadur SHRESTHA 《Rice science》 SCIE CSCD 2015年第1期35-43,共9页
The use of improved high yielding crop varieties is an important avenue for reducing hunger and food insecurity in developing countries. Using cross-sectional data obtained from a survey conducted during 2013 crop sea... The use of improved high yielding crop varieties is an important avenue for reducing hunger and food insecurity in developing countries. Using cross-sectional data obtained from a survey conducted during 2013 crop season, we performed a probit model (plot-level analysis) to determine the probability of adopting new improved rice varieties (NIRVs) by smallholder farmers particularly from two main agro-ecological regions (hills and tropical plain terai regions) of Central Nepal. The results revealed that education, extension services and seed access play significant roles in adoption decisions. Additionally, farm and field characteristic variables such as farm size, endowment of favorable land type (e.g. lowlands), and animal power (e.g. oxen) are the key factors influencing the probability of adopting NIRVs. The results showed that technology specific variables (e.g. yield potential and acceptability) are significant for explaining adoption behavior, implying that it is important to take farmers' preferences to varietal characteristics into consideration in the design of a research and development program. Given the significant role played by extension and access related variables, increased emphasis on information dissemination, field demonstration, and farmers' participatory research and training programs to popularize new rice varieties and enhance their adoption rate are required. This also suggests that policy intervention should be made on improving the educational status of farming households, and developing programs on varietal package of rice seed which offer farmers a variety of choices among the appropriate pools of germplasm. Such programs ultimately help farmers develop more profit-oriented behavior which are necessary to enhance adoption rate, production and food security in the long run. 展开更多
关键词 ADOPTION improved rice variety probit model tropical terai region technology specific characteristic
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Ecological intensification of cropping systems enhances soil functions,mitigates soil erosion,and promotes crop resilience to dry spells in the Brazilian Cerrado 被引量:2
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作者 Lucas de Castro Moreira da Silva Junior Cesar Avanzi +5 位作者 Devison Souza Peixoto Marina Neves Merlo Emerson Borghi Alvaro Vilela de Resende Salvador Francisco Acuna-Guzman Bruno Montoani Silva 《International Soil and Water Conservation Research》 SCIE CSCD 2021年第4期591-604,共14页
Water scarcity threatens global food security and agricultural systems are challenged to achieve high yields while optimizing water usage.Water deficit can be accentuated by soil physical degradation,which also trigge... Water scarcity threatens global food security and agricultural systems are challenged to achieve high yields while optimizing water usage.Water deficit can be accentuated by soil physical degradation,which also triggers water losses through runoff and consequently soil erosion.Although soil health in cropping systems within the Brazilian Cerrado biome have been surveyed throughout the years,information about soil erosion impacts and its mitigation are still not well understood;especially concerning the role of cropping system diversification and its effects on crop yield.Thus,the aim of this study was to assess whether ecological intensification of cropping systems-inclusion of a consorted perennial grass and crop rotation-could promote soil coverage and consequently decrease water erosion and soil,water,and nutrient losses.This work studied the effects of crop rotation and consorted Brachiaria,along with different levels of investment in fertilization on soil physical quality and on soil,water,and nutrient losses,and crop yields.Results proved that soybean monoculture(SS)is a system of low sustainability even under no-till in the Brazilian Cerrado conditions.It exhibited high susceptibility to soil,water,and nutrient losses,causing low crop yields.Our results showed that water losses in SS cropping system were approximately 10%of the total annual rainfall,and total K losses would require an additional 35%of K application.Conversely,ecological intensification of cropping systems resulted in enhanced soil environmental and agronomic functions,increased grain yield,and promoted soil and water conservation:high soil cover rate,and low soil,water and nutrient losses.Ecological intensification proved to be an adequate practice to boost crop resilience to water deficit in the Brazilian Cerrado. 展开更多
关键词 Crop rotation Grain production Nutrient losses Soil physical quality tropical region
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