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Impact of Removal of Copper Leaf (<i>Acalypha fruticosa</i>Forssk.) on Plant Species Diversity and Abundance at Chemeron, Baringo County, Kenya

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Open Journal of Ecology 2020年第6期10卷 341-355页

作者： George Morara Ogendi Rhoda N. Ondieki tabitha w. njoroge Department of Environmental Science Egerton University Njoro Kenya Dryland Research Training & Ecotourism Centre Chemeron Egerton University Njoro Kenya

Invasive plant species may significantly alter plant species community composition and structure thereby negatively impacting on ecosystem services. Their impacts on plant communities may be both direct and indirect. The direct effects may include a reduction in the abundance and diversity of palatable plant species that constitute important forage for livestock, w.ldlife, and medicines for the local communities. Declines in ecosystem resilience are of the notable indirect effects of invasive species. The aim of this study w.s to assess the impacts of a plant species, copper leaf (Acalypha fruticosa) on floral diversity and abundance at Chemeron, Baringo County in Kenya. The study w.s guided by three questions: w.at is the plant composition in terms of grasses, herbs, shrubs, and trees in the study area? Are there any variations in plant abundance betw.en the tw. sites (sites w.th and w.thout Acalypha fruticosa)? Are there variations in plant species diversity betw.en the tw. study sites? Tw. sites (one w.th A. fruticosa and another tw. w.thout this invasive species) w.re selected w.thin the Chemeron Research Centre. Tw. belt transects measuring 100 m × 20 m on each site w.re laid parallel to each other. Plant samples w.re collected from five 1 m × 1 m quadrats that w.re laid at intervals of 20 m. The plant species or specimens w.re identified to the species level using available taxonomic keys. Various indices including Shannon-w.ener (H’), Evenness Index, Richness Index and Simpson’s Index of Diversity Index (SDI) w.re calculated. All the diversity, richness and evenness indices w.re considerably higher in the site w.thout A. fruticosa compared to that w.ere this invasive species w.s present. Higher H’ (3.14 to 3.21) and SDI (0.93 to 0.94) values w.re noted in sites w.thout the invasive species compared to H’ (2.11 to 2.20) and SDI (0.77 to 0.85) in sites w.th A. fruticosa present. Out of the

关键词： Baringo Copper Leaf Diversity Indices Invasive Species Plant Diversity

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Isolation and Characterization of SARS-CoV-2 in Kenya

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American Journal of Molecular Biology 2024年第2期14卷 66-83页

作者： Albina Makio Robinson Mugasiali Irekw. Matthew.Mutinda Munyao Caroline w.ngui njoroge Peter Kipkemboi Rotich Tonny Teya Nyandw.ro Joanne Jepkemei Yego Anne w.njiru Mw.ngi James Hungo Kimotho Ronald Tanui Vincent Rutto Samson Muuo Nzou Center for Traditional Medicine and Drug Research Kenya Medical Research Institute Nairobi Kenya Center for Microbiology Research Kenya Medical Research Institute Nairobi Kenya Production Department Kenya Medical Research Institute Nairobi Kenya Department of Biochemistry and Microbiology Rhodes University Grahamstown South Africa Center for Virus Research Kenya Medical Research Institute Nairobi Kenya

The discovery of Severe Acute Respiratory Syndrome-Coronavirus-2 (SARS-CoV-2) in w.han, Hubei province, China, in December 2019 raised global health w.rnings. Quickly, in 2020, the virus crossed borders and infected individuals across the w.rld, evolving into the COVID-19 pandemic. Notably, early signs of the virus’s existence w.re observed in various countries before the initial outbreak in w.han. As of 12th of April, the respiratory disease had infected over 762 million people w.rldw.de, w.th over 6.8 million deaths recorded. This has led scientists to focus their efforts on understanding the virus to develop effective means to diagnose, treat, prevent, and control this pandemic. One of the areas of focus is the isolation of this virus, w.ich plays a crucial role in understanding the viral dynamics in the laboratory. In this study, w. report the isolation and detection of locally circulating SARS-CoV-2 in Kenya. The isolates w.re cultured on Vero Cercopithecus cell line (CCL-81) cells, RNA extraction w.s conducted from the supernatants, and reverse transcriptase-polymerase chain reaction (RT-PCR). Genome sequencing w.s done to profile the strains phylogenetically and identify novel and previously reported mutations. Vero CCL-81 cells w.re able to support the grow.h of SARS-CoV-2 in vitro, and mutations w.re detected from the tw. isolates sequenced (001 and 002). Genome sequencing revealed the circulation of tw. isolates that share a close relationship w.th the Benin isolate w.th the D614G common mutation identified along the S protein. These virus isolates w.ll be expanded and made available to the Kenya Ministry of Health and other research institutions to advance SARS-CoV-2 research in Kenya and the region.

关键词： SARS-CoV-2 COVID-19 w.ole Genome Sequencing Phylogenetic Analysis Nucleotide Substitutions Amino Acid Changes

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Physical, Total Phenolic and Total Flavonoid Properties of Chia (Salvia hispanica L.) Seeds Grow. in Kenya

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Food and Nutrition Sciences 2022年第12期13卷 973-985页

作者： Pauline w. Ikumi Monica Mburu Daniel njoroge Nicholas Gikonyo Benjamin Musyimi Musingi Institute of Food and Bioresources Technology Dedan Kimathi University of Technology Nyeri Kenya National Phytotherapeutics Research Centre Kenyatta University Nairobi Kenya Animal Breeding and Genomics Group Department of Animal Sciences Egerton University Egerton Kenya Department of Biological Sciences Egerton University Egerton Kenya

In the recent past, there has been an increased uptake of chia seeds (Salvia hispanica L.) by consumers resulting in the increased adoption of chia farming, particularly in Kenya w.ereby most farmers are practising subsistence farming and a few.farming it commercially. The w.despread farming of chia seeds in Kenya translates to increased uptake at household level w.ile offering a niche for industrial processing of chia seeds necessitating the need for studies on physical, total phenolic and flavonoid properties of chia seeds grow. in Kenya. The physical, total phenolic and flavonoid properties of chia seeds from tw. chia planning seasons April to August 2019 and September to December 2019 w.re evaluated. The physical attributes (length, w.dth and thickness) w.re determined using a digital vernier calliper w.ile proximate components w.re determined using AOAC standard methods. The Quencher procedure w.s used to determine the total phenolic and flavonoid contents. Chia seeds revealed a length of 1.82 to 2.32 (mm), a w.dth of 1.15 to 1.31 (mm) and a thickness of 0.77 to 0.88 (mm). The percentage moisture content of chia seeds w.s 7.23 to 10.67, percentage of crude fat w.s 31.48 to 42.45, percentage of crude ash w.s 3.63 to 6.82, and percentage of crude fibre w.s 30.95 to 38.65 and percentage of crude protein w.s17.82 to 28.97. The total phenolic content observed for chia seeds w.s 0.73 to 0.87 mg GAE g-1 w.ile total flavonoid content w.s 0.39 to 0.57 mg GAE g-1. The proximate components of chia seeds varied significantly (p w.ile the physical properties, total phenolics and total flavonoid contents did not vary significantly.

关键词： Chia (Salvia hispanica L.) Seeds Properties

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Review. Advances in the CIGS Thin Films for Photovoltaic Applications

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Smart Grid and Renew.ble Energy 2022年第4期13卷 75-87页

作者： Phyllis Makena Mw.nda w.lter njoroge Sarroney Mirenga Dickson Mw.nda Kinyua Department of Physics Kenyatta University Nairobi Kenya Department of Physical Sciences Meru University of Science and Technology Meru Kenya Department of Pure and Applied Sciences Kirinyaga University Kerugoya Kenya

The copper indium gallium selenium (CIGS) thin film is w.dely acknow.edged as the most promising material for photovoltaic applications. Mainly due to appealing chemical and physical structures properties, low.fabrication cost, high efficiency, and uncomplicated integration especially w.th the advancement in the use of the flexible substrate. Promising results have been achieved in CIGS-based solar cells in the last few.years and these devices could be key in unlocking the potential of green energy. Therefore, it is necessary to understand the parameters that are critical to improving the efficiency of these devices. Parameters such as doping concentration, thickness, substrates, and energy bandgap. In this review. w. comprehensively report on these parameters w.th an aim of show.ng the recent progress on the various methods used to optimize them, all geared tow.rds efficient and low.cost solar cells for PV applications.

关键词： CIGS Thin Films Photovoltaics Efficiency

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Crystallization kinetics of Sn_(40)Se_(60) thin films for phase change memory applications

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Journal of Semiconductors 2015年第6期36卷 17-20页

作者： Joshua M.Kundu Patrick M.Karimi w.lter K.njoroge Department of Physics Kenyatta University

The crystallization kinetics of Sn4oSe6o thin films has been successfully investigated using sheet resis- tance versus temperature measurements. Thermal evaporation w.s used to deposit the films on ordinary glass sub- strates. The crystallization temperature for Sn4oSe60 thin film w.s found to be 156.6 -t- 0.3 ~C. In the as-deposited state, the sheet resistance w.s found to be 195 Mf2/[2, this value declined to 1560 f2/[2] upon annealing. The value of activation energy obtained from the Kissinger plot w.s 0.62 ＋ 0.07 eV. From the results obtained, SnaoSe60 is a promising alloy for PCM application because of its high electrical contrast, high crystallization temperature, and relatively high activation energy.

关键词： crystallization temperature activation energy electrical contrast phase change memory

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欧洲企业社会责任协会会员部主任Susan njoroge:欧洲CSR的2020战略

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w.O经济导刊 2010年第6期 57-58页

作者： Susan njoroge 欧洲企业社会责任协会会员部

对于企业社会责任，欧盟给予了持续的重视。2008年欧委会起草的《欧洲竞争力报告》将欧洲CSR提到很高的高度，指出如果企业想要发展，所有的CEO、总裁必须注意CSR，CSR可以帮助企业进行人力资源风险和商誉的管理。报告指出全球CSR的趋势... 详细信息

对于企业社会责任，欧盟给予了持续的重视。2008年欧委会起草的《欧洲竞争力报告》将欧洲CSR提到很高的高度，指出如果企业想要发展，所有的CEO、总裁必须注意CSR，CSR可以帮助企业进行人力资源风险和商誉的管理。报告指出全球CSR的趋势，CSR会带来很多创新的商业模式，并且会为应对社会和经济挑战带来很多新的解决方式。

关键词：企业社会责任 CSR Susan 欧洲协会会员部主任人力资源风险 2008年

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季节性干旱驱动亚热带森林的碳积累

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Journal of Plant Ecology 2023年第1期16卷 241-256页

作者： Brian njoroge Yuelin Li Dennis Otieno Shizhong Liu Simin w.i Ze Meng Qianmei Zhang Deqiang Zhang Juxiu Liu Guow.i Chu Fasih Ullah Haider John Tenhunen Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems South China Botanical GardenChinese Academy of SciencesGuangzhou 510650China Guangdong Provincial Key Laboratory of Applied Botany South China Botanical GardenChinese Academy of SciencesGuangzhou 510650China University of Chinese Academy of Sciences Beijing 100039China Department of Botany Jaramogi Oginga Odinga University of Science and TechnologyBondo 210-40601Kenya Department of Plant Ecology University of Bayreuth95440 BayreuthGermany

本研究旨在表明处于南亚热带的鼎湖山生物圈保护区的干旱频率和强度正在增加,并说明季节性干旱对亚热带森林碳积累的影响。这是为了应对全球气候变化导致的干旱加剧所带来的威胁开展的一项研究。我们使干旱指数(标准化降水指数、标准降... 详细信息

本研究旨在表明处于南亚热带的鼎湖山生物圈保护区的干旱频率和强度正在增加,并说明季节性干旱对亚热带森林碳积累的影响。这是为了应对全球气候变化导致的干旱加剧所带来的威胁开展的一项研究。我们使干旱指数(标准化降水指数、标准降水蒸散发指数、降水距平百分率及自校准帕尔默干旱指数)准确确定干旱期和降水量增加期。此后,将2003至2014年(12年)监测采集的实测涡动通量和土壤含水量数据在干旱期和湿润期之间进行比较,以确定干旱对生态系统碳积累的影响。在本研究所选择的12年期间,干旱的发生时间约占比20%,最强干旱事件和严重程度发生于2012至2013年。研究期间的年平均降水量和气温分别为1404.57±43.2 mm和22.65±0.1°C,与30年记录(1990–2020)相比较,年降水量减少量可达523 mm,而气温则增加了2.55°C。与全球针对大多数森林生态系统研究所发表的数据呈相反趋势,处于中国南亚热带区域的鼎湖山生物圈保护区在60%的干旱期内所监测的森林生态系统记录到显著的碳积累趋势,说明季节性干旱驱动了森林的碳积累。

关键词：干旱气候变化碳积累鼎湖山生物圈保护区涡动通量

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Variation of morphological and leaf stoichiometric traits of tw. endemic species along the elevation gradient of Mount Kenya, East Africa

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Journal of Plant Ecology 2020年第6期13卷 785-792页

作者： Antony N.w.igw. Brian njoroge Mw.ngi Gituru R.w.hiti Fred Omengo Yadong Zhou Qingfeng w.ng Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture Wuhan Botanical GardenChinese Academy of SciencesWuhan 430074China University of Chinese Academy of Sciences Beijing 100049China Sino-Africa Joint Research Center(SAJOREC) Jomo Kenyatta University of Agriculture and TechnologyJujaNairobi 00200Kenya Department of Biodiversity Research Kenya Wildlife ServiceNairobi 00100Kenya Center of Conservation Biology Core Botanical GardensChinese Academy of SciencesWuhan 430074China Sino-Africa Joint Research Center(SAJOREC) Chinese Academy of SciencesWuhan 430074China

环境能一定程度上影响和改变植物的形态结构和生理生化。本文旨在拟研究热带东非高山不同海拔梯度下两种代表植物Dendrosenecio keniensis和Lobelia gregoriana的形态结构和生理生化的变化。我们沿海拔梯度在海拔3500 m至4300 m的范围... 详细信息

环境能一定程度上影响和改变植物的形态结构和生理生化。本文旨在拟研究热带东非高山不同海拔梯度下两种代表植物Dendrosenecio keniensis和Lobelia gregoriana的形态结构和生理生化的变化。我们沿海拔梯度在海拔3500 m至4300 m的范围内建立了90个10 m×10 m的样方,使用1 km×1 km网格单元在ArcGis 10.5中栅格化研究区域并获取每个样方的气候数据,包括年平均气温、年平均降水量、年总辐射量、水汽压,同时获取了每个样方的地形变量,包括坡向、坡度和阴影等。我们收集了每个样方两种植物的形态性状,包括株高、叶面积、叶厚、叶干重、比叶面积,以及叶化学计量性状,包括氮、碳、磷的含量,同时收集了样方的土壤有机碳、土壤全氮、土壤有机氮和土壤磷数据。我们将海拔高度设为解释变量,对两种植物的形态性状和叶片化学计量性状进行线性回归分析,同时,在海拔梯度上对叶片形态和化学计量性状与气候、土壤和地形变量进行了相关分析。我们的研究发现,***有羊毛状的短柔毛叶,而***则有粘液填充的肉质和蜡质的角质层叶子,以避免冻害。这两个物种都呈现出了降低的代谢率,表现在叶片磷含量较低。我们的研究结果还表明,形态和叶片化学计量的变化是由气候、土壤和地形变量共同决定的,这些变量随肯尼亚山海拔的变化而变化。我们推测,沿海拔梯度两种植物的形态和叶片化学计量性状的变异是对恶劣环境条件的适应。

关键词：非洲海拔梯度功能特性适应性气候变化

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Preference and adoption of Farmer Field School (FFS) Prosopis juliflora management practices: Experiences in Baringo District, Kenya

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Forestry Studies in China 2012年第4期14卷 283-290页

作者： Eunice njoroge Peter SIRMAH Francis MBURU Eric KOECH Mugo Mw.RE Josiah CHEPKw.NY School of Natural Resource Management Moi University School of Natural Resource Management Kabianga University

This research w.s carried out to evaluate the preference and adoption of harvesting, uprooting, stump burning, pruning and thinning practices for controlling the spread ofProsopisjuliflora （prosopis） w.thin Marigat Division of the Baringo District, Kenya. A survey methodology w.s employed using a random sample of 25 Farmer Field School （FFS） members and 5 non=FFS members from each of the five locations of Marigat Division. In total, 100 FFS members and 25 non-FFS members participated in the study; addi- tional supplementary data w.re collected from the Kenya Forestry Research Institute （KEFRI）, a major facilitator and trainer of the identified FFS activities and practices in the study area since 2004. More than 80% of the local community never undertook any form of prosopis management practice; how.ver, this changed after FFS training, indicating an acquisition and retention of know.edge w.ich probably diffused to the non-FFS counterparts, through either formal or informal w.ys. Harvesting w.s the most preferred （100%） and stump burning the least preferred （46%） practice of managing the spread of prosopis. The success and preference of any prosopis management practice w.s attributed to w.od and non-w.od benefits derived from prosopis and grow.ng of animal fodder and food crops on rehabilitated land. More than 80% of respondents attributed ineffectiveness of any prosopis management practice to coppicing and viable seed banks of the tree, w.ile 50% highlighted a lack of consistency and integration in carrying out manage- ment practices. The reported negative attitude tow.rds prosopis changed after training w.th none of the view.to eradicate it. Labor intensity and frequent regeneration of seedlings w.re identified as the major challenges faced during the implementation of proso- pis management practices. In conclusion, the study show. that harvesting, uprooting, stump burning, pruning and thinning realized through consistent holistic integration contribute to containi

关键词： Prosopisjuliflora Farmer Field School management practices Baringo Kenya

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Effects of deep vertical rotary tillage on the grain yield and resource use efficiency of w.nter w.eat in the Huang-Huai-Hai Plain of China

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Journal of Integrative Agriculture 2021年第2期20卷 593-605页

作者： w. Fen ZHAI Li-chao XU Ping ZHANG Zheng-bin Elamin Hafiz BAILLO Lemessa Negasa TOLOSA Roy njoroge KIMOTHO JIA Xiu-ling GUO Hai-qian Center for Agricultural Resources Research Institute of Genetics and Developmental BiologyChinese Academy of Sciences/Key Laboratory of Agricultural Water ResourcesChinese Academy of Sciences/Hebei Key Laboratory of Water-saving AgricultureShijiazhuang 050022P.R.China University of Chinese Academy of Sciences Beijing 100049P.R.China Institute of Cereal and Oil Crops Hebei Academy of Agricultural and Forestry SciencesShijiazhuang 050035P.R.China Shijiazhuang Agricultural Products Quality Testing Center Shijiazhuang 050021P.R.China

Tillage represents an important practice that is used to dynamically regulate soil properties,and affects the grain production process and resource use efficiency of *** objectives of this 3-year field study carried out in the Huang-Huai-Hai(HHH) Plain of China w.re to compare the effects of a new.deep vertical rotary tillage (DVRT) w.th the conventional shallow.rotary tillage (CT) on soil properties,w.nter w.eat (Triticum aestivum L.) grain yield and w.ter and nitrogen use efficiency at different productivity levels,and to identify a comprehensive management that optimizes both grain yield and resource use efficiency in the HHH Plain.A split-plot design w.s adopted in field experiments in the w.nter w.eat grow.ng seasons of 2016–2017 (S1),2017–2018 (S2) and 2018–2019 (S3),w.th DVRT (conducted once in June 2016) and CT performed in the main *** w.re treated w.th one of four targeted productivity level treatments (SH,the super high productivity level;HH,the high productivity and high efficiency productivity level;FP,the farmer productivity level;ISP,the inherent soil productivity level).The results show.d that the soil bulk density w.s reduced and the soil w.ter content at the anthesis stage w.s increased in all three years,w.ich w.re due to the significant effects of *** w.th CT,grain yields,partial factor productivity of nitrogen (PFP_(N)),and w.ter use efficiency (w.E) under DVRT w.re increased by 22.0,14.5 and 19.0%.Path analysis and direct correlation decomposition uncovered that grain yield variation of w.nter w.eat w.s mostly contributed by the spike numbers per area under different tillage *** line model analysis revealed that tillage mode played a significant role on grain yield,PFP_(N) and w.E not only as a single factor,but also along w.th other factors(year and productivity level) in interaction *** addition,PFP_(N) and w.E w.re the highest in HH under DVRT in all three grow.h *** results provided a th

关键词： w.nter w.eat deep vertical rotary tillage resource use efficiency w.ter use efficiency partial factor productivity of nitrogen

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