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Review of Innovative Agricultural Market Creation in Africa and the Study of Three-tier Model for Soybean Development and Promotion in Kenya

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Journal of Life Sciences 2010年第3期4卷 43-51页

作者： Jonas Nwankwo Chianu bernard vanlauwe Akinwumi Adesina Justina Nwanganga Chianu NteranyaSanginga Tropical Soil Biology and Fertility Institute of the International Center for Tropical Agriculture （TSBF-CIA T） c / o Worm Agroforestry Center （ICRAF） UN Avenue Nairobi 00100 Kenya Department of Agriculture and Agro-industry （OSAN） Agricultural Fertilizer Financing Mechanism （AFFM） Belvedere Tunis 1002 Tunisia Alliance for a Green Revolution in Africa Westlands Nairobi 00800 Kenya

Agricultural market creation was critical for rural growth in Africa. How to achieve this based on crops other than major staples （e.g. maize） and traditional export crops （e.g., tea, coffee, cotton） remained a problem since most African countries did not give them policy attention. This study used a three-tier-model, developed based on successful strategies in Nigeria and Zimbabwe, to develop multi-level soybean market creation in Kenya. Data were from secondary sources, formal and informal interviews, farm-level data, and participant observations. Analysis was carried out using Microsoft Excel and SPSS. Result showed increasing in farmers＇ confidence to produce, process, consume, and sell more soybeans than before. Trained farmers＇ groups were developing new soybean products for cash, poverty reduction and improvements in livelihoods. Net returns had been increased from 4 to 14 times from processed products. Selected farmers＇ groups had begun to supply large-scale processors with soybean grains, substituting imports. The overall project＇s impact on number of participating farmer groups and the actual land area devoted to soybean cultivation ranged from a factor of 2.3 to a factor of 77.4 between the long rainy seasons of 2005 / 2006 and the short rainy seasons of 2009. Farmers had given testimonies on live improvements.

关键词： Agricultural market creation three-tier-model soybean Africa Kenya.

Soil Properties Degradation Assessment Using Infrared Scanning Technique of Soils （Case Study： Eastern of Congo）

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Journal of Agricultural Science and Technology(A) 2013年第9期3卷 677-688页

作者： Bashagaluke Janvier Mulumuna Janvier Pieter Pypers Walangululu Jean Shepherd Keith MochogeBenson Mugwe Jayne vanlauwe bernard Boeckx Pascal Universite Catholique De Bukavu (UCB) DR Congo Kenyatta University Nairobi Kenya Laboratory of Applied Physical Chemistry--lSOFYS Faculty of Bioscience Engineering Ghent University Coupure 6539000Gent Belgium Tropical Soil Biology and Fertility of the International Institute of Tropical Agriculture (TSBF-CIA T) Nairobi Kenya World Agro-forestry Center (ICRAF) Nairobi Kenya

Recently, near infrared reflectance （NIR） and mid-infrared （MIR） spectroscopy techniques are increasingly introduced as convenient and simple non-destructive techniques for quantifying several soil properties. This study uses MIR method to predict pH, soil organic C, total N, AI, Ca, Mg and K, CEC and soil texture for soil samples collected in Sud-Kivu, Congo. A total of 536 composite soil samples were taken from two locations （Burhale and Luhihi） at two depths （0-20 cm and 20-40 cm） using a spatially-stratified random sampling design within an area of 200 km2. Differences in characteristics were evaluated between the two locations, land use （cultivated vs. non-cultivated land） with soil depths. A random subset of the samples （10%） were analyzed using standard wet chemistry methods, and calibration models developed by MIR data to estimate soil properties for the full soil sample set. Partial least squares regression （PLS） method gave acceptable coefficients of determination between 0.71 and 0.93 for all parameters. Soil organic matter levels were higher in cultivated plots in Luhihi （3.9% C） than in Burhale （3.0% C）, suggesting lower levels of soil fertility in the later area. This indicates high levels of acidity, which are likely to limit crop production in the area. Phosphorus deficiency is acute in Burhale （2.4 mg P/kg） but less in Luhihi （5.4 mg P/kg）. In both locations, low levels of Ca and Mg indicate that soils may be susceptible to deficiencies in both *** findings provide new opportunities for monitoring soil quality in the region which can benefit multiple actors and scientists involved in the agricultural and environmental sectors.

关键词： Parameter depth infrared correlation prediction landuse.

Knowledge, Attitude and Practices Used in the Control of Striga in Maize by Smallholder Farmers of Western Kenya

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Journal of Agricultural Science and Technology(B) 2014年第3期4卷 237-248页

作者： Godfrey Nakitare Nambafu Richard Ndemo Onwonga George Njomo Karuku Emmanuel Safaris Ariga bernard vanlauwe Kristina Roing de Nowina Department of Land Resource Management and Agricultural Technology University of Nairobi Nairobi 29053 Kenya International Institute of Tropical Agriculture (IITA) Nairobi 30772-00100 Kenya Department of Plant Science and Crop Protection University of Nairobi Nairobi 29053 Kenya Department of Soil and Environment Swedish University of Agricultural Science Uppsala 7070 SE-750 07 Sweden

The production of maize is constrained by parasitic weeds, particularly Striga. A study was carried out to document farmers＇ knowledge, attitude and practices on Striga control among smallholder farmers across three districts： Kisumu West, Busia and Teso South of Western Kenya. A multistage sampling technique was used to select the locations and farmers to be interviewed. A semi structured, open and closed ended questionnaire was administered leading to field experiment. Besides village meetings （39.2%）, farmers got informed on farming methods under Striga weed farms and its control technologies through neighbours （2.5%）, workshops and trainings （5.0%）, field schools （3.7%）, media （7.5%） and extension agents （10.8%）. The attitudes of farmers towards Striga control varied but frequently cited： long term viability of the Striga seed （12.5%）, difficult to control sharing of farm tools （10.8%）, expensive technologies （13.3%）, lack of adequate information （18.3%）, labour intensive （15.0%）, large farms for use of push and pull technology （1.7%） and time consuming （12.5%）. Framers used various Striga control practices but traditional methods （25%） were among the most used （25%）. Concerted effort involving researchers, extension agents and private sector are, therefore, required for wide scale dissemination and adoption of the existing modem control technologies.

关键词： Attitude knowledge practice striga control technologies.

由标准气象站数据估计出的非洲撒哈拉以南土壤的气候和分解者活动:土壤碳平衡计算的一个简单气候指数

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AMBIO－人类环境杂志 2007年第5期36卷 361-368页

作者： Olof Andrén Job Kihara André Bationo bernard vanlauwe Thomas Ktterer 王胜瑞典农业大学(SLU)土壤科学系热带农业国际中心热带土壤生物和肥力研究所 TSBF-CIAT 瑞典农业大学(SLU)

本文逐日计算了土壤的生物学活动,使用的是非洲气象站的标准气象数据、一个简单的土壤水分模型,并且使用了关于温度、土壤含水量和生物学活动之间关系的一般性假设。活动系数r_(e_clim)由日土壤湿度和温度计算得出,从而考虑了温度与湿... 详细信息

本文逐日计算了土壤的生物学活动,使用的是非洲气象站的标准气象数据、一个简单的土壤水分模型,并且使用了关于温度、土壤含水量和生物学活动之间关系的一般性假设。活动系数r_(e_clim)由日土壤湿度和温度计算得出,从而考虑了温度与湿度之间的交互作用。瑞典中部(粘壤土,无作物)r_(e_clim)的年均值标准化为1,在那里进行了最初的校准。由于土壤在储水能力和植物覆被上的差异会对蒸腾作用产生影响,所以我们选择的样地均为无作物的该土壤,这样就只包括了气候差异。瑞典r_(e_clim)值,1,相当于诸如表土中含有的谷类秸杆等的年质量亏损约50%。非洲r_(e_clim)年均值在干热地点(法亚,乍得)为1.1,温湿地点(布拉柴维尔,刚果)为4.7之间变动。肯尼亚样地的r_(e_clim)值为2.1(高海拔,Matanya)至4.1(肯尼亚西部,Ahero)。这意味着假如土壤类型和经营相同,那么必须有4.1倍于瑞典的碳输入才能将Ahero的土壤碳水平维持在瑞典水平。对每一块样地都绘制了r_(e_clim)日动态图,并讨论了年内动态差异。模拟实验表明,如果将土壤碳平衡的瑞典土壤移至肯尼亚的Ahero,30年内其土壤碳将损失41%。如果将Ahero保持碳平衡的土壤移至瑞典,30年内其土壤碳含量将增加64%。本文讨论了方法与结论的有效性,并将r_(e_clim)与其它气候指数进行了对比。本文还提出了一种对r_(e_clim)值进行粗略估计的简易方法。

关键词：气候指数土壤碳平衡计算标准化气象站非洲估计分解者

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A Secure Mutual Authentication Protocol Based on Visual Cryptography Technique for IoT-Cloud

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Chinese Journal of Electronics 2024年第1期33卷 43-57页

作者： Brou bernard Ehui Chen CHEN Shirui WANG Hua GUO Jianwei LIU School of Cyber Sciences and Technology Beihang University State Key Laboratory of Software Development Environment Beihang University Sino-French Engineering School Beihang University Beihang Hangzhou Innovation Institute Yuhang

Because of the increasing number of threats in the IoT cloud, an advanced security mechanism is needed to guard data against hacking or attacks. A user authentication mechanism is also required to authenticate the user accessing the cloud services. The conventional cryptographic algorithms used to provide security mechanisms in cloud networks are often vulnerable to various cyber-attacks and inefficient against new attacks. Therefore,developing new solutions based on different mechanisms from traditional cryptography methods is required to protect data and users’ privacy from attacks. Different from the conventional cryptography method, we suggest a secure mutual authentication protocol based on the visual cryptography technique in this paper. We use visual cryptography to encrypt and decrypt the secret images. The mutual authentication is based on two secret images and *** user requests the ticket from the authentication server(AS) to obtain the permission for accessing the cloud services. Three shared secret keys are used for encrypting and decrypting the authentication process. We analyze the protocol using the Barrows-Abadi-Needham(BAN)-logic method and the results show that the protocol is robust and can protect the user against various attacks. Also, it can provide a secure mutual authentication mechanism.

关键词： Visualization Cloud computing Data privacy Protocols Biometrics (access control) Authentication Resists

Spirotetramat reduces fitness of the spotted-wing Drosophila,Drosophila suzukii

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Insect Science 2024年第4期31卷 1222-1230页

作者： Jing Yang Justin Flaven-Pouchon Yiwen Wang bernard Moussian Section of Animal Genetics Interfaculty Institute of Cell BiologyUniversity of TübingenTübingenGermany School of Pharmaceutical Science and Technology Tianjin UniversityTianjinChina INRAE CNRSUniversitéCôte d'AzurInstitut Sophia AgrobiotechSophia AntipolisFrance

With climate change,the spotted-wing Drosophila(SWD,Drosophila suzukii)invades a great number of fruit production regions worldwide.A plethora of insecticides are being applied for management of this *** expected,SWD develops resistance against some potent insecticides or is rather insensitive to some ***,there is an urgent need to identify and characterize alternative insecticides to control SWD ***,we have studied the effects of the orally applied inhibitor of the fatty acid synthesis pathway spirotetramat on SWD fitness with respect to fecundity and surface barrier function at different *** our experiments,we applied spirotetramat mixed with baker's yeast and showed that females and males were not repelled by effective concentrations of this *** found that spirotetramat,by trend,lowers egg numbers laid by fed *** eggs rapidly desiccate,and only a few larvae *** is lethal to larvae and reduces survival of adult flies under low-humidity *** together,based on our data,we propose to use yeast supplemented with spirotetramat and additional SWD-specific attractants in traps in non-crop areas in order to eradicate SWD populations before they infest crop production sites.

关键词： desiccation Drosophila suzuki insecticide lipids

Monitoring absolute vertical land motions and absolute sea-level changes from GPS and tide gauges data over French Polynesia

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Geodesy and Geodynamics 2024年第1期15卷 13-26页

作者： Xianjie Li Jean-Pierre Barriot bernard Ducarme Marania Hopuare Yidong Lou Geodesy Observatory of Tahiti University of French PolynesiaFaa'a 98702French Polynesia Catholic University of Louvain Georges Lemaître Centre for Earth and Climate Research(ELI)1348 Louvain-la-NeuveBelgium GNSS Research Center Wuhan UniversityWuhan 430079China State Key Laboratory of Information Engineering in Surveying Mapping and Remote SensingWuhan UniversityWuhan 430079China

In this study,we estimate the absolute vertical land motions at three tidal stations with collocated Global Navigation Satellite System(GNSS)receivers over French Polynesia during the period 2007-2020,and obtain,as ancillary results,estimates of the absolute changes in sea level at the same *** verify our processing approach to determining vertical motion,we first modeled vertical motion at the International GNSS Service(IGS)THTI station located in the capital island of Tahiti and compared our estimate with previous independent determinations,with a good *** obtained the following estimates for the vertical land motions at the tide gauges:Tubuai island,Austral Archipelago-0.92±0.17 mm/yr,Vairao village,Tahiti Iti:-0.49±0.39 mm/yr,Rikitea,Gambier Archipelago-0.43±0.17 mm/*** absolute variations of the sea level are:Tubuai island,Austral Archipelago 5.25±0.60 mm/yr,Vairao village,Tahiti Iti:3.62±0.52 mm/yr,Rikitea,Gambier Archipelago 1.52±0.23 mm/*** discuss these absolute values in light of the values obtained from altimetric measurements and other means in French Polynesia.

关键词： GPS Tide gauges Sea level changes Vertical land motion

维普期刊数据库

Functional trait composition of carabid beetle communities predicts prey suppression through both mass ratio and niche complementarity mechanisms

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Insect Science 2024年第2期31卷 562-574页

作者： Abdelhak Rouabah Francoise Lasserre-Joulin Sylvain Plantureux Simon Taugourdeau bernard Amiaud Universite de Loraine INRAELAENancyF-54000France UMR SELMET CIRADINRAEInstitut AgroUniversite de MontpellierMontpellier34000France CIRAD UMR SELMET-PPZSDakarSéenegal UMR Siva Universitéde LorraineAgroParisTechINRAEVandoeuvreLes Nancy54506France

Several components of predator functional diversity have been hypothesized to influence prey suppression through either niche complementarity or mass ratio ***,most studies have used a functional group approach when assessing the role of these predators in ecosystem *** adopting a trait-based approach,we evaluated the relative contributions of carabid diversity components in predicting prey *** results highlight the importance of both taxonomic and functional diversity components of carabids as key drivers of prey *** suppression was best predicted by carabid densities,with the dominance of Poecilus cupreus potentially driving the positive effect of community total abundance through the mass ratio *** suppression increased with increasing the density of large *** addition,carabid eye diameter and antennal length were key functional traits for predicting prey ***,prey suppression increased with increasing carabid functional richness following the niche complementarity *** contrast to functional richness,functional evenness and functional divergence of carabid communities were weakly correlated with prey *** identifying which diversity components of carabid communities contribute the most to increase prey suppression,our results can guide efforts aiming to predict the relationship between diversity of these predators and ecosystem functioning.

关键词： abundance distribution biological control body size ecosystem function functional richness predator-prey interactions

Role of CYP311A1 in wing development of Drosophila melanogaster

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Insect Science 2024年第3期31卷 748-758页

作者： Xubo Zhang Mengqi Liu Andi Cheng bernard Moussian Jianzhen Zhang Wei Dong Shanxi Key Laboratory of Nucleic Acid Biopesticides Institute of Applied BiologyShanxi UniversityTaiyuanChina College of Life Science Shanxi UniversityTaiyuanChina INRAE CNRSInstitut Sophia AgrobiotechSophia AntipolisUniversite Cote d'AzurNiceFrance

Lipid homeostasis is crucial for growth and development of *** cytochrome P450 monooxygenases(CYPs)are involved in lipid *** function of Cyp3llal in the anterior midgut as a regulator of phosphatidylethanolamine(PE)metabolism in Drosophila melanogaster has been demonstrated,as depletion of Cyp31lal caused larval growth arrest that was partially rescued by supplying *** this study,we investigated the role of CYP311A1 in wing morphogenesis in *** the GAL4-UAS system,Cyp31lal was selectively knocked down in the wing disc.A deformed wing phenotype was observed in flies with reduced Cyp31lal *** and oil red O staining revealed a reduction of neutral lipids in the wing disc after the depletion of *** addition,we observed an enhanced sensitivity to Eosin Y penetration in the wings of Cyp31lal knocked-down ***,the reduction of CYP311A1 function in developing wings does not affect cell proliferation and apoptosis,but entails disordered Phalloidin or Cadherin distribution,suggesting an abnormal cell morphology and cell cortex structure in wing epithelial *** together,our results suggest that Cyp3llal is needed for wing morphogenesis by participating in lipid assembly and cell homeostasis.

关键词： apoptosis cell cortex cell proliferation Cyp31lal lipid wing