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Climate change and its association with the expansion of vectors and vector-borne diseases in the Hindu Kush Himalayan region:A systematic synthesis of the literature

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Advances in Climate Change Research 2021年第3期12卷 421-429页

作者： meghnath DHImAL Isabelle marie KRAmER Parbati PHUYAL Shyam Sundar BUDHATHOKI Juliane HARTKE Bodo AHRENS Ulrich KUCH David AGRONEBERG Santosh NEPAL Qi-Yong LIU Cun-Rui HUANG Gueladio CISSE Kristie LEBI Doris KLINGELHOFER ruth mULLER Nepal Health Research Council(NHRC) Kathmandu44600Nepal Global Institute for Interdisciplinary Studies(GIIS) Kathmandu44600Nepal Institute of Occupational Social and Environmental MedicineGoethe UniversityFrankfurt am Main60590Germany Institute for Atmospheric and Environmental Sciences(IAU) Goethe UniversityFrankfurt am Main60438Germany Department of Biomedical Sciences Institute of Environment and Sustainable DevelopmentUniversity of AntwerpAntwerp2000Belgium Department of Primary Care and Public Health School of Public HealthImperial College LondonLondonW2 IPGUnited Kingdom Department of Biomedical Sciences Institute of Tropical MedicineAntwerp2000Belgium International Centre for Integrated mountain Development(ICImOD) Kathmandu44600Nepal Department of Vector Biology and Control National Institute for Communicable Disease Control and PreventionChina CDCBeijing102206China WHO Collaborating Centre for Vector Surveillance and management Beijing102206China Department of Health Policy&management School of Public HealthSun Yat-sen UniversityGuangzhou510275China Department of Epidemiology and Public Health(EPH) Swiss Tropical and Public Health Institute(Swiss TPH)Basel4051Switzerland University of Basel Basel4001Switzerland Department of Global Health University of WashingtonSeattleWA98104USA

Observed weather and projected climate change suggest an increase in the transmission of vector-borne diseases(VBDs)in the Hindu Kush Himalayan(HKH)*** this study,we systematically explore the literature for empiric associations between the climate variables and specific VBDs and their vectors in the HKH *** conducted a systematic synthesis of the published literature on climate variables,VBDs and vectors in the HKH region until the 8th of December *** majority of studies show significant positive associations of VBDs with climatic factors,such as temperature,precipitation,relative humidity,*** systematic review allowed us to identify the most significant variables to be considered for evidence-based trend estimates of the effects of climate change on VBDs and their vectors in the HKH *** evidence-based trend was set into the context of climate change as well as the observed expansion of VBDs and disease vectors in the HKH *** geographic range of VBDs expanded into previously considered non-endemic areas of highlands(mountains)in the HKH region.B ased on scarce,but clear evidence of a positive relationship of most climate variables and VBDs and the observed climatic changes,we strongly recommend an expansion of vector control and surveillance programmes in areas of the HKH region that were previously considered to be non-endemic.

关键词： Chikungunya Dengue Filariasis High altitude Himalayas Leishmaniasis mountain mosquito malaria Sandfly

Use of Kostiakov’s Infiltration model on michael Okpara University of Agriculture, Umudike Soils, Southeastern, Nigeria

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Journal of Water Resource and Protection 2014年第10期6卷 888-894页

作者： magnus U. Igboekwe ruth U. Adindu Department of Physics Michael Okpara University of Agriculture Umudike Nigeria Department of Physics/Electronics Abia State Polytechnic Aba Nigeria

The main purpose of this study is to obtain the water infiltration parameters of the soils of michael Okpara University of Agriculture, Umudike. This could be used in simulating infiltration for these soils when designing irrigation projects, thereby saving time and cost of field measurement. Field measurements of infiltration were first made using a double ring infiltrometer. The test lasted for 180 mins in each location. Infiltration values ranged from 0.03 cm/min to 0.1 cm/min. The highest value was obtained in the Forest Block. Kostiakov’s infiltration model was then applied on the field data in order to determine the soils’ infiltration parameters and equations. The model empirical constants or parameters obtained were “m” and “n”. For “m” the values were: 0.53 for the soil of Forest Block, 0.42 for Poultry block, 0.50 for P.G. block, 0.41 for the soils of Staff School and Guest House. The corresponding “n” values were: 1.37, 1.12, 0.37, 1.79, and 1.38. Infiltration equations: 0.4It1.38, 0.4lt1.79, 0.42t1.12, and 0.53t1.37 were determined for the locations. These were used to simulate data which were evaluated by comparing them with the field data. The two data sets showed closed relationships. This implied that the model could be used to simulate water infiltration during irrigation projects in the farms of michael Okpara University of Agriculture, Umudike.

关键词： Kostiakov model Parameters Infiltration Soil Water Irrigation

Structural Controls on the Geochemistry and Output of the Wells in the Olkaria Geothermal Field of the Kenyan Rift Valley

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International Journal of Geosciences 2016年第11期7卷 1299-1309页

作者： ruth N. Wamalwa Christopher m. Nyamai Willis J. Ambusso Josephat mulwa Aaron K. Waswa Kenya Electricity Generating Company—KenGen Naivasha Kenya Department of Geology University of Nairobi Nairobi Kenya School of Pure and Applied Sciences Kenyatta University Nairobi Kenya

The Olkaria geothermal field is located in the Kenya Rift valley, about 120 km from Nairobi. Geothermal activity is widespread in this rift with 14 major geothermal prospects being identified. Structures in the Greater Olkaria volcanic complex include: the ring structure, the Ol’Njorowa gorge, the ENE-WSW Olkaria fault and N-S, NNE-SSW, NW-SE and WNW-ESE trending faults. The faults are more prominent in the East, Northeast and West Olkaria fields but are scarce in the Olkaria Domes area, possibly due to the thick pyroclastics cover. The NW-SE and WNW- ESE faults are thought to be the oldest and are associated with the development of the rift. The most prominent of these faults is the Gorge Farm fault, which bounds the geothermal fields in the northeastern part and extends to the Olkaria Domes area. The most recent structures are the N-S and the NNE-SSW faults. The geochemistry and output of the wells cut by these faults have a distinct characteristic that is the N-S, NW-SE and WNW-ESE faults are characterized by wells that have high Cl contents, temperatures and are good producers whereas the NE-SW faults, the Ring Structure and the Ol’Njorowa gorge appear to carry cool dilute waters with less chloride concentration and thus low performing wells. Though the impacts of these faults are apparent, there exists a gap in knowledge on how wide is the impact of these faults on the chemistry and performance of the wells. This paper therefore seeks to bridge this gap by analysis of the chemical trends of both old wells and newly drilled ones to evaluate the impacts of individual faults and then using buffering technique of ArcGis estimate how far and wide the influence of the faults is. The data was obtained after the sampling and analysis of discharge fluids of wells located on six profiles along the structures cutting through the field. Steam samples were collected with a stainless steel Webre separator connected between the wellhead and an atmospheric silencer on the disc

关键词： Structural Controls Geochemistry Productivity Buffering Olkaria Geothermal Field Kenya

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制作反馈放大器的增益稳定度计算

通信与信息技术 1972年第2期 37-40页

作者： A.m.morgan VOYCE

为了扩大放大器在精密设备中的应用,预先知道它的增益稳定度对于设计者和使用者都是重要的。这里详细的述明一种计算放大器增益稳定度的方法,它立足于开环增益的闭合比:应用于设计和推导固体及电子管放大器两种状态的一种方法。 (?)反... 详细信息

为了扩大放大器在精密设备中的应用,预先知道它的增益稳定度对于设计者和使用者都是重要的。这里详细的述明一种计算放大器增益稳定度的方法,它立足于开环增益的闭合比:应用于设计和推导固体及电子管放大器两种状态的一种方法。 (?)反馈用于稳定一个放大器的增益,其方程式如下:

关键词：限制 IL

ASTROSAT/UVIT Near and Far Ultraviolet Properties of the m31 Bulge

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International Journal of Astronomy and Astrophysics 2021年第2期11卷 151-174页

作者： Denis Leahy Cole morgan Josep Postma megan Buick Department of Physics and Astronomy University of Calgary Calgary Canada

AstroSat has surveyed m31 with the UVIT telescope from 2017 to 2019. The central bulge of m31 was observed in 2750 - 2850 A, 2000 - 2400 A, 1600 - 1850 A, 1450 - 1750 A, and 1200 - 1800 A filters. A radial profile analysis, averaged along elliptical contours which approximate the bulge shape, was carried out in each filter. The profiles follow a Sersic function with an excess for the inner ~8" in all filters, or can be fitted with two Sersic functions (including the excess). The ultraviolet colours of the bulge are found to change systematically with radius, with the center of the bulge bluer (hotter). We fit the UVIT spectral energy distributions (SEDs) for the whole bulge and for 10 elliptical annuli with single stellar population (SSP) models. A combination of two SSPs fits the UVIT SEDs much better than one SSP, and three SSPs fit the data best. The properties of the three SSPs are age, metallicity (m>Zm>) and mass of each SSP. The best fit model is a dominant old, metal-poor (1010 yr, mg src="Edit_***" alt="" />, with mg src="Edit_***" alt="" /> the solar metallicity) population plus a 15% contribution from an intermediate (109.5 yr, ) population plus a small contribution (~2%) from a young high-metallicity (108.5 yr, mg src="Edit_***" alt="" />) population. The results are consistent with previous studies of m31 in optical: both reveal an active merger history for m31.

关键词： UV Astronomy Galaxies: m31

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高灵敏度微流控芯片液压油固体颗粒检测研究

高灵敏度微流控芯片液压油固体颗粒检测研究

作者： ruth GEBRTSADIK CHEGEN（陈庆茹）大连海事大学

学位级别：硕士

在现代工业中,机械维护至关重要,如果没有适当的维护,设备故障或破坏将不可避免的。对于重要的机械来说,故障维修并不具有成本效益,而基于时间的预防性维修可能成本很高。因此,急需一个实用的、可负担的机械维护计划。最常见的故障类型... 详细信息

在现代工业中,机械维护至关重要,如果没有适当的维护,设备故障或破坏将不可避免的。对于重要的机械来说,故障维修并不具有成本效益,而基于时间的预防性维修可能成本很高。因此,急需一个实用的、可负担的机械维护计划。最常见的故障类型是磨损,它是由机械部件的接触带来的,并导致粘着性或研磨性磨损。在机械系统中,被污染的油可能通过加速磨损而加速设备故障。提高油检测传感器的灵敏度对于检测微粒子至关重要,而油液监测对于避免和诊断机械故障至关重要。本篇论文研究了用于通过仔细观察油的状态来防止系统故障的多种技术。然而,这些技术各有缺点,例如敏感性差,可能会降低其有效性。为了克服这些限制,本论文提出了一种极其敏感的传感器。该传感器由单层线圈组成,线圈上附有铁基纳米晶带材。由于铁基纳米晶带材具有很强的磁导率、磁感应强度和较低的磁芯损耗,它有助于提高传感器的灵敏度。利用电感和电阻信号,该系统可以识别磁性和非磁性颗粒。非铁磁性金属颗粒可被电感信号检测和区分,但电阻信号只能检测但不能区分金属颗粒。一项比较有铁基纳米晶带材和无铁基纳米晶带材的传感器的实验表明,铁基纳米晶带材改善了电感和电阻信号中的磁化和涡流效应。因此,这表明带有铁基纳米晶带材的传感器比没有带材的传感器具有更高的灵敏度。实验结果显示,使用电感信号,没有铁基纳米晶带材的传感器无法识别小于40μm的铁颗粒和小于76μm的铜颗粒。然而,带有铁基纳米晶带材的传感器可以检测到铜和铁的颗粒,分别小到60μm和19μm。在使用电阻信号时,有铁基纳米晶带材和无铁基纳米晶带材的传感器都无法检测到本实验中使用的任何铁颗粒。尽管如此,在使用电阻信号时,没有铁基纳米晶带材的传感器能够识别小至55μm的铜颗粒,而有铁基纳米晶带材的传感器也能够使用电阻信号检测到小至45μm的铜颗粒。这项研究表明,使用铁基纳米晶带材可以提高传感器的灵敏度,本研究中采用的传感器有用于机器状态监测和液压系统诊断的前景。

关键词：高灵敏度电感信号电阻信号粒子检测传感器