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11.
Getachew Gudero Mengesha Habtamu Terefe Yetayew Asela Kesho Sako 《Archives Of Phytopathology And Plant Protection》2013,46(11-12):575-601
AbstractField surveys were conducted in 2014 and 2015 to determine the distribution and association of wilt incidence with biophysical factors. Spatio-temporal analysis of wilt epidemics in the farms revealed a wide distribution of the disease. Cropping year, district, cultivar, crop density, planting date, weeding, sucker and bud management, source of moisture and planting materials, presence/absence of wilt in neighboring farms, disease management practices, farmers awareness towards wilt diseases, planting date and cropping system were significantly associated with disease incidence in a multiple-variable model. A wilt incidence of ≤30% had high probability of association to good weed, sucker and male bud management practices, high level of farmers awareness towards wilt, low population density, disease-free suckers, rainfed production, absence of wilt in neighboring farms and good disease management schemes. Findings of this study showed Fusarium wilt is a major constraint and need for on-farm trainings to concerned bodies about wilt management schemes. 相似文献
12.
Within and among population genetic diversity of 37 Guizotia abyssinica populations from Ethiopia were analyzed using inter simple sequence repeats (ISSRs). Five primers amplified a total of 118 genomic DNA fragments across a total of 370 individuals of which 106 were polymorphic (89.83%). The average number of polymorphic bands per primer was 21.2. More bands were generated by primer UBC 888 (BDB(CA)(7.) The total genetic diversity (Ht) and the coefficient of genetic differentiation (Gst) were 0.4115 and 0.0918 respectively, while the within population genetic diversity (Hs) and the among population genetic diversity(Dst) were 0.3738 and 0.03776 respectively suggesting more variability within the populations than among them. The standard genetic distances between the G. abyssinica populations of the eight regions ranged from 0.0281 (between Wollo and Gojam) to 0.1148 (between Jimma and Hararghe). Generally, the standard genetic distances are smaller between populations of neighboring regions and highest between those of Jimma and the other regions, ranging from 0.0696 (between Jimma and Shewa) to 0.1148 (between Jimma and Hararghe). The ISSR based UPGMA clustering using the standardized genetic distances matrix also placed populations from neighboring regions closer than those from farther apart areas, while the UPGMA clustering by regions based on the standard genetic distances produced three clusters following the proximity and the contiguity of the regions. The mean Shannon Weaver diversity indices for the populations of the eight regions ranged from 0.8197 (Jimma) to 0.9176 (Hararghe), with a mean of 0.8841 for the whole material. 相似文献
13.
Huang Zhu Khan Manan Xu Jianze Khan Teka Ma Hui Khan Ranjha Hussain Hafiz Muhammad Jafar Jiang Xiaohua Shi Qinghua 《中国科学:生命科学英文版》2019,62(4):544-552
The balanced actions between ubiquitination and deubiquitination precisely control the levels of various proteins vital for spermatogenesis. Ubiquitin-specific processing proteases(USPs) are the largest family of deubiquitinatingenzymes(DUBs),containing more than 50 members. So far, the functions of only a few USPs in male fertility have been studied, the roles of the majority are yet unknown. The present study aimed to explore the function of Usp29(ubiquitin-specific protease 29) in male fertility. We found that Usp29 showed predominant expression in mouse testis, and its m RNA expression started to increase at 14 days postpartum(dpp), with a peak at 28 and 35 dpp. Using CRISPR/Cas9 technology, we generated Usp29 knockout mice(Usp29~(–/–)). Usp29~(–/–)mice exhibited no overt developmental anomalies. Further examination revealed that Usp29~(–/–)mice had normal fertility and showed no detectable difference in the testis/body weight ratio, testicular and epididymal histology as well as epididymal sperm count from the wild-type littermates. Moreover, Usp29 is not a pseudogene in mice. Taken together, our study first reported that though Usp29 is predominantly expressed in the testis, it is not essential for male fertility in mice. 相似文献
14.
Matthew J. Burton Saul N. Rajak Athumani Ramadhani Helen A. Weiss Esmael Habtamu Baye Abera Paul M. Emerson Peng T. Khaw David C. W. Mabey Martin J. Holland Robin L. Bailey 《PLoS neglected tropical diseases》2012,6(12)
Background
Surgery for trachomatous trichiasis (TT) is a key component of the SAFE Strategy for trachoma control. Unfortunately, recurrent TT following surgery is common, probably due to various surgical and disease factors. To develop strategies to reduce recurrence rates it is necessary to understand its pathological basis. In this study we investigated the relationship between recurrent trichiasis and the expression of various cytokines and fibrogenic genes during a two-year follow-up period.Methodology/Principal Findings
Individuals undergoing surgery for TT were examined at baseline (pre-operative), 6, 12, 18 and 24 months. Conjunctival swab samples were collected from the tarsal conjunctiva for RNA isolation on each occasion. Individuals who developed recurrent TT with at least 3 lashes touching the eye on one or more occasion were designated “cases” and an equal number of “controls” were randomly selected from those without recurrent TT, frequency matched for age and baseline TT severity. The expression of the following genes was measured by quantitative RT-PCR: S100A7, IL1B, CXCL5, TNFA, NOS2A, CTGF, MMP7, MMP9 and MMP12. Thirteen hundred individuals were enrolled and underwent surgery. By two years 122 had developed recurrent TT with at least 3 lashes touching the eye. Recurrent TT was consistently associated across multiple time points with about a 2-fold increase in S100A7 expression (p = 0.008). Clinically visible conjunctival inflammation was associated with increased S100A7, IL1B, CXCL5, MMP9 and MMP12 expression.Conclusions/Significance
Increased S100A7 expression was associated with trachomatous conjunctival scarring and may be linked to the pathophysiology of recurrent TT. S100A7 expression could be a potential biomarker for this disease process. As part of the epithelial innate immune response S100A7 has multiple actions, potentially contributing to a chronic pro-inflammatory response, which may lead to ongoing tissue damage and increased scarring. 相似文献15.
Habtamu Giday Dimitrios Fanourakis Katrine H. Kjaer Inge S. Fomsgaard Carl-Otto Ottosen 《Annals of botany》2013,112(9):1857-1867
Background and Aims
Stomata formed at high relative air humidity (RH) respond less to abscisic acid (ABA), an effect that varies widely between cultivars. This study tested the hypotheses that this genotypic variation in stomatal responsiveness originates from differential impairment in intermediates of the ABA signalling pathway during closure and differences in leaf ABA concentration during growth.Methods
Stomatal anatomical features and stomatal responsiveness to desiccation, feeding with ABA, three transduction elements of its signalling pathway (H2O2, NO, Ca2+) and elicitors of these elements were determined in four rose cultivars grown at moderate (60 %) and high (90 %) RH. Leaf ABA concentration was assessed throughout the photoperiod and following mild desiccation (10 % leaf weight loss).Key Results
Stomatal responsiveness to desiccation and ABA feeding was little affected by high RH in two cultivars, whereas it was considerably attenuated in two other cultivars (thus termed sensitive). Leaf ABA concentration was lower in plants grown at high RH, an effect that was more pronounced in the sensitive cultivars. Mild desiccation triggered an increase in leaf ABA concentration and equalized differences between leaves grown at moderate and high RH. High RH impaired stomatal responses to all transduction elements, but cultivar differences were not observed.Conclusions
High RH resulted in decreased leaf ABA concentration during growth as a result of lack of water deficit, since desiccation induced ABA accumulation. Sensitive cultivars underwent a larger decrease in leaf ABA concentration rather than having a higher ABA concentration threshold for inducing stomatal functioning. However, cultivar differences in stomatal closure following ABA feeding were not apparent in response to H2O2 and downstream elements, indicating that signalling events prior to H2O2 generation are involved in the observed genotypic variation. 相似文献16.
Getachew Gudero Mengesha Habtamu Terefe Yetayew 《Archives Of Phytopathology And Plant Protection》2013,46(19-20):1066-1089
AbstractField surveys were conducted to determine the spatiotemporal distribution and the association of disease intensity with cropping systems and other environmental factors in Southern Ethiopia during 2016 and 2017. In both years, a total of 190 bean fields were surveyed in five districts, and common bacterial blight (CBB) was 100% prevalent. But disease incidence and severity varied among districts and between cropping years. Bean planting in Arbaminch suffered from 31% to 38%, 6–13%, 12–17% and 8–12% higher CBB severity than bean cultivation in Burjdi, Mihirab Abaya, Demba Gofa and Konso districts, respectively. The associations of disease parameters with independent factors were assessed using the logistic regression analyses. District, cropping year, altitude, land preparation, cropping system, fertiliser application, planting date, growth stage and weed infestation were associated with both disease incidence and severity with variable levels of significance. Common bean genotype was also significantly (P?<?.005) associated with disease severity in a multiple variable model. Concerning incidence, variable associations were demonstrated by the model. These results indicate that CBB is severe and highly prevalent in Southern Ethiopia. Therefore, efforts should be geared towards crop residue management, optimal tillage and fertiliser application, weeding, clean seed source and early planting approach to manage the disease. 相似文献
17.
Habtamu E Rajak SN Gebre T Zerihun M Genet A Emerson PM Burton MJ 《PLoS neglected tropical diseases》2011,5(4):e1014
Background
In 2006 there were an estimated 645,000 people in Amhara, Ethiopia, with trachomatous trichiasis (TT) who needed surgery. Despite an extensive integrated eye care worker training programme (IECW) and robust support for TT surgical services, productivity has not reached targets. We investigated why surgeon productivity was below target.Methodology/Principal Findings
Confidential interviews were conducted in person with TT surgeons trained from 24 selected districts in Amhara Region and their supervisors. Determinants of attrition and productivity were investigated. We interviewed 225 people who had received IECW training; 139 (59%) had subsequently changed career/job. Staff retention was associated with good road access to their health centre, mobile telephone network and a shorter time from initial training. Amongst the 94 IECW still working in the programme, the average number of patients operated was 41/year, which was mostly (86%) done through outreach campaigns and only 14% of cases were performed in the static facilities where they routinely worked. Spot checks were made of surgical instruments and consumables: only 3/94 IECW had the minimum instruments and consumables to perform surgery. The main barriers to operating were lack of time, shortage of consumables, lack of patients, lack of support and equipment problems. Very few IECW received ongoing supervision or active management.Conclusions/Significance
Surgeon attrition rates are high. Vertical surgery campaigns were effective in treating large numbers of cases, whilst static-site service productivity was low. Good health system management is key to building a well-staffed and well-run service. 相似文献18.
Habtamu K. Benecha John S. Preisser Kimon Divaris Amy H. Herring Kalyan Das 《Biometrical journal. Biometrische Zeitschrift》2018,60(4):845-858
Unlike zero‐inflated Poisson regression, marginalized zero‐inflated Poisson (MZIP) models for counts with excess zeros provide estimates with direct interpretations for the overall effects of covariates on the marginal mean. In the presence of missing covariates, MZIP and many other count data models are ordinarily fitted using complete case analysis methods due to lack of appropriate statistical methods and software. This article presents an estimation method for MZIP models with missing covariates. The method, which is applicable to other missing data problems, is illustrated and compared with complete case analysis by using simulations and dental data on the caries preventive effects of a school‐based fluoride mouthrinse program. 相似文献
19.
Elie A. Padonou Oscar Teka Yvonne Bachmann Marco Schmidt Anne Mette Lykke Brice Sinsin 《African Journal of Ecology》2015,53(1):83-92
Bowalization is a particular form of land degradation and leads to lateral expansion of ferricrete horizons. The process occurs only in tropical regions. In this study, the most adapted and resistant species towards climate change were identified on bowé. The 15 most common bowé species of the subhumid and semi‐arid climate zones of Benin were submitted together with significant environmental variables (elevation, current bioclimatic variables, soil types) to three ecological niche modelling programmes (Maxent, Domain and GARP). For future prediction (2050), IPCC4/CIAT and IPCC5/CMIP5 climate data were applied. Asparagus africanus, Andropogon pseudapricus and Combretum nigricans were identified as the most resistant species for ecological restoration of bowé in the semi‐arid climate zone and Asparagus africanus, Detarium microcarpum and Lannea microcarpa in the subhumid climate zone. The ‘Pull’ strategies were identified as appropriate for ecological restoration of bowé in Benin. 相似文献
20.