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141.
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143.
Ghada Kchour SA Rahim Rezaee Reza Farid Akram Ghantous Houshang Rafatpana Mahdi Tarhini Mohamad-Mehdi Kooshyar Hiba El Hajj Fadwa Berry Roudaina Nasser Abbas Shirdel Zeina Dassouki Mohamad Ezzedine Hossein Rahimi Ardeshir Ghavamzadeh Hugues de Thé Olivier Hermine Mahmoud Mahmoudi Ali Bazarbachi 《Retrovirology》2014,11(Z1):O4
144.
Alan Gray David Odee Stephen Cavers Julia Wilson Annika Telford Fiona Grant Mayécor Diouf John Ochieng Helen Grant Andy Stott 《Plant and Soil》2013,369(1-2):479-496
Background and aims
Acacia senegal, a leguminous dryland tree, is economically and ecologically important to sub-Saharan Africa. Water-use efficiency (WUE) and biological nitrogen fixation (BNF) are fundamental to plant productivity and survival. We quantify provenance differences in WUE, BNF, photosynthesis, biomass and gum arabic production from A. senegal assessing genetic improvement potential.Methods
Using stable isotope ratios, we determined WUE (δ13C) and BNF (δ15N) from provenances of mature A. senegal in field-trials (Senegal), sampling leaves at the beginning (wet) and end (dry) of the rainy season. Seedling provenance trials (UK) determined photosynthesis, and biomass and δ13C in relation to water table. Environmental data were characterised for all provenances at their sites of origin.Results
Provenances differed in both δ13C and δ15N. Gum yield declined with increasing WUE. Virtually no BNF was detected during the dry season and seedlings and mature trees may have different WUE strategies. Wind speed and soil characteristics at provenance origin were correlated with isotope composition and gum production.Conclusion
Provenance differences suggest that selection for desirable traits, e.g., increased gum production, may be possible. As ecological strategies relate to native locality, the environmental conditions at plantation site and provenance origin are important in assessing selection criteria. 相似文献145.
为了解不同玉米品种对草地贪夜蛾生长发育的影响,本文通过比较草地贪夜蛾Spodoptera frugiperda取食2种糯质型玉米(明玉1203和苏玉糯5号)与3种普通玉米(苏玉29、苏玉30和郑单958)后的发育历期、死亡率、蛹重、成虫畸形率、繁殖力与幼虫取食选择率等生物学参数,分析了草地贪夜蛾对不同品种玉米的适应性差异.结果表明:以糯质型玉米饲养的草地贪夜蛾幼虫发育历期与成虫寿命均长于取食普通玉米的个体,而蛹重与单雌产卵量低于取食普通玉米的个体.草地贪夜蛾最高总体死亡率(50.82%)与成虫畸形率(41.38%)均来自于取食糯质型玉米明玉1203处理,而最低总体死亡率(37.29%)与成虫畸形率(12.50%)则分别来自于取食糯质型玉米苏玉糯5号和普通玉米苏玉30处理组.此外,仅6龄幼虫对不同玉米品种的取食偏好性存在显著差异,更倾向于取食普通玉米.综合可见,草地贪夜蛾对普通玉米的适应性好于糯质型玉米,且对糯质型玉米明玉1203的适应性最差.研究结果为所选品种玉米的安全生产与草地贪夜蛾的发生为害评估奠定了研究基础. 相似文献
146.
Kye Chung Park Junwei Zhu Jennifer Harris Samuel A. Ochieng Thomas C. Baker 《Physiological Entomology》2001,26(1):69-77
The parasitic wasp Microplitis croceipes (Cresson) (Hymenoptera: Braconidae) showed its own characteristic electroantennogram (EAG) response profiles to 13 host‐related (cis‐3‐hexenol, α‐pinene (R)‐(+)‐limonene (S)‐(–)‐limonene, trans‐β‐ocimene (±)‐linalool, (–)‐trans‐caryophyllene, α‐humulene, nerolidol, trans‐nerolidol, cis‐nerolidol, methyl jasmonate and indole) and four anthropogenic (2‐diisopropylaminoethanol, 2,2′‐thiodiethanol, 2‐methyl‐5‐nitroaniline and cyclohexanone) volatile compounds. These profiles were similar between males and females except for 2‐diisopropylaminoethanol, which elicited significantly larger EAG responses in males. Among the compounds tested, cis‐3‐hexenol, linalool and cyclohexanone elicited the largest EAG responses. EAG responses were not influenced by the age of wasps between 1 and 13 days after emergence. EAG responses were dose‐dependent, and highly EAG‐active compounds elicited significant EAG responses with less than 10 μg of the compounds at source. Quantification of compounds released from an odour cartridge indicates that release rate is highly dependent on the chemical nature of stimuli, showing up to 10 000‐fold differences in the amount released between different compounds when the same amount was loaded in the odour cartridge. Wasps having undergone a behavioural training regime to be attracted to either cyclohexanone or methyl jasmonate did not show any differences in EAG responses from those of untrained wasps. 相似文献
147.
BD Pascal MJ Chalmers SA Busby CC Mader MR Southern NF Tsinoremas PR Griffin 《BMC bioinformatics》2007,8(1):156
Background
The combination of mass spectrometry and solution phase amide hydrogen/deuterium exchange (H/D exchange) experiments is an effective method for characterizing protein dynamics, and protein-protein or protein-ligand interactions. Despite methodological advancements and improvements in instrumentation and automation, data analysis and display remains a tedious process. The factors that contribute to this bottleneck are the large number of data points produced in a typical experiment, each requiring manual curation and validation, and then calculation of the level of backbone amide exchange. Tools have become available that address some of these issues, but lack sufficient integration, functionality, and accessibility required to address the needs of the H/D exchange community. To date there is no software for the analysis of H/D exchange data that comprehensively addresses these issues. 相似文献148.
Stephen Fredrick Omondi Eunice Wamuyu Githae John Otieno Ochieng 《African Journal of Ecology》2015,53(3):295-303
Conventionally, local seed sources are normally believed to perform better than introduced materials. However, studies show possibility of contrary results with many species such as Acacia senegal. The species is an economically and ecologically important tree of arid and semi‐arid lands of sub‐Saharan Africa. It produces gum arabic, used in land reclamation and agroforestry production. The species is however underutilized in Kenya due to lack of information on growth performance of different seed sources. Glasshouse provenance trial using seeds and soils from seven provenances in Kenya were used to evaluate interactions between seed sources and soils on growth and biomass. Seedling growth was assessed for 12 weeks in a randomized complete block design. Seed length, width, thickness and weight were measured. Seedlings height, root collar diameter, root dry weight, shoot dry weight and biomass were assessed and data subjected to univariate and multivariate analyses. No significant interaction between seed provenance and soils were evident; however, some provenances performed better across all the soils. Significant heritability and relationship between growth and environmental factors are reported. Overall, Ntumburi and Ngarendare provenances showed superior growth and plasticity. These provenances can be used tentatively as seed sources; however, field trials are recommended. 相似文献
149.
S. M. Thumbi M. Kariuki Njenga Thomas L. Marsh Susan Noh Elkanah Otiang Peninah Munyua Linus Ochieng Eric Ogola Jonathan Yoder Allan Audi Joel M. Montgomery Godfrey Bigogo Robert F. Breiman Guy H. Palmer Terry F. McElwain 《PloS one》2015,10(3)
Background
For most rural households in sub-Saharan Africa, healthy livestock play a key role in averting the burden associated with zoonotic diseases, and in meeting household nutritional and socio-economic needs. However, there is limited understanding of the complex nutritional, socio-economic, and zoonotic pathways that link livestock health to human health and welfare. Here we describe a platform for integrated human health, animal health and economic welfare analysis designed to address this challenge. We provide baseline epidemiological data on disease syndromes in humans and the animals they keep, and provide examples of relationships between human health, animal health and household socio-economic status.Method
We designed a study to obtain syndromic disease data in animals along with economic and behavioral information for 1500 rural households in Western Kenya already participating in a human syndromic disease surveillance study. Data collection started in February 2013, and each household is visited bi-weekly and data on four human syndromes (fever, jaundice, diarrhea and respiratory illness) and nine animal syndromes (death, respiratory, reproductive, musculoskeletal, nervous, urogenital, digestive, udder disorders, and skin disorders in cattle, sheep, goats and chickens) are collected. Additionally, data from a comprehensive socio-economic survey is collected every 3 months in each of the study households.Findings
Data from the first year of study showed 93% of the households owned at least one form of livestock (55%, 19%, 41% and 88% own cattle, sheep, goats and chickens respectively). Digestive disorders, mainly diarrhea episodes, were the most common syndromes observed in cattle, goats and sheep, accounting for 56% of all livestock syndromes, followed by respiratory illnesses (18%). In humans, respiratory illnesses accounted for 54% of all illnesses reported, followed by acute febrile illnesses (40%) and diarrhea illnesses (5%). While controlling for household size, the incidence of human illness increased 1.31-fold for every 10 cases of animal illness or death observed (95% CI 1.16–1.49). Access and utilization of animal source foods such as milk and eggs were positively associated with the number of cattle and chickens owned by the household. Additionally, health care seeking was correlated with household incomes and wealth, which were in turn correlated with livestock herd size.Conclusion
This study platform provides a unique longitudinal dataset that allows for the determination and quantification of linkages between human and animal health, including the impact of healthy animals on human disease averted, malnutrition, household educational attainment, and income levels. 相似文献150.
Tabu C Breiman RF Ochieng B Aura B Cosmas L Audi A Olack B Bigogo G Ongus JR Fields P Mintz E Burton D Oundo J Feikin DR 《PloS one》2012,7(2):e31237