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11.
Analysis of household's energy consumption,forest degradation and plantation requirements in Eastern Tigray,Northern Ethiopia
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This study examines the link between household's energy consumption, forest degradation and plantation requirements in Eastern Tigray. Data on household's fuelwood, cow‐dung, kerosene and electricity consumption in the study sites were collected from 557 urban and 114 rural households. Deforestation rate was estimated following FAO and Woody Biomass Inventory Strategy Planning Project (WBISPP's) conversion factors. The study showed that household's fuelwood consumption in urban areas (mean = 2.5 kg/day) was about 52% lower as compared to the rural villages (mean = 3.8 kg/day). The estimated area abandoned annually in the vicinity of urban areas as the result of urban fuelwood consumption varies from 217 ha around Maichew town to 12047 ha around Mekelle City. The estimated area abandoned in rural areas annually as the result of tree cutting for fuelwood also varies from 6.5 ha around Sinkata to 127 ha around Dergajen village. It is therefore recommended that an estimated annual tree plantation of area ranging from 286 ha around Maichew town to 21,684 ha around Mekelle city is required. Moreover, an estimated annual tree plantation of area ranging from 16 ha around Sinkata village to 229 ha around the Dergajen village is required taking the existing population into account. 相似文献
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Renato M Salgado Luciane P Capelo Rodolfo R Favaro Jocelyn D Glazier John D Aplin Telma MT Zorn 《Reproductive biology and endocrinology : RB&E》2009,7(1):60
Background
Remodeling of the extracellular matrix is one of the most striking features observed in the uterus during the estrous cycle and after hormone replacement. Versican (VER) is a hyaluronan-binding proteoglycan that undergoes RNA alternative splicing, generating four distinct isoforms. This study analyzed the synthesis and distribution of VER in mouse uterine tissues during the estrous cycle, in ovariectomized (OVX) animals and after 17beta-estradiol (E2) and medroxyprogesterone (MPA) treatments, either alone or in combination. 相似文献14.
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Hua Chen Kassa Semagn Muhammad Iqbal Neshat Pazooki Moakhar Teketel Haile Amidou N’Diaye Rong-Cai Yang Pierre Hucl Curtis Pozniak Dean Spaner 《Molecular breeding : new strategies in plant improvement》2017,37(11):141
We recently reported genomic regions associated with resistance to four wheat diseases and insensitivity to three Pyrenophora tritici-repentis toxins in an association mapping panel consisting of 81 diverse Canadian western spring wheat (Triticum aestivum L.) cultivars. Here, we report genomic regions and SNPs associated with days to heading, plant maturity, plant height, test weight (grain volume weight), grain yield, and grain protein content in the same population using genome-wide association studies (GWAS). The 81 spring wheat cultivars were evaluated for the above six traits across six environments and genotyped with 19,919 polymorphic SNPs and 14 gene-specific markers. Using mixed liner model and a threshold of p ≤ 3.1 × 10?4, we identified a total of 139 significant marker-trait associations that were mapped at 19 genomic regions on 11 chromosomes for heading (3 regions), maturity (2), plant height (3), test weight (3), grain yield (6), and grain protein (2). Each region consisted of clusters of markers ranging from 2 to 33 and individually explained from 4.5 to 26.1% of the phenotypic variation averaged over six environments. Some the genomic regions identified in the present study are novel, while others, such as the regions for grain protein on 1B, days to heading on 5A, plant height on 4B, and test weight on 7A, were located close to either known genes or QTLs reported in previous studies, but direct comparisons in some cases were challenging due to lack of common set of markers and reliable physical positions among the different studies. Results from this study provide additional information to wheat researchers developing improved spring wheat cultivars. 相似文献
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Gonadal and extragonadal sperm reserves were determined in testicular and epididymal tissues obtained from Boran (n=10) and Boran x Friesian (n=12) bulls fed either a high or low plane nutrition diet for a 1-year period. The bulls were 32 months of age at castration. Mean (+/-SEM) daily body weight gains over a 1-year period were 776+/-34 and 264+/-34 g/day (P<0.001) for bulls on high and low nutrition, and their respective body weights at castration were 458+/-17 and 276+/-17 kg (P<0.01). Mean body weights did not differ between Boran and Boran x Friesian bulls. Mean scrotal circumference measurements were 32.1+/-0.6 and 28.8+/-0.6 cm for the high and low planes of nutrition (P<0.01) and 31.8+/-0.7 and 29.2+/-0.6 cm for the Boran and the Boran x Friesian bulls (P<0.05). Paired testes and epididymal weights averaged 432+/-22 and 313+/-22 g (P<0.01) and 46.3+/-2.0 and 32.5+/-2.0 g (P<0.001) for bulls on the high and low planes of nutrition, respectively. Boran x Friesian bulls had significantly heavier (P<0.05) testes, but epididymal weithts did not differ between breeds. Although daily sperm production per gram was not influenced by either plane of nutrition or breed, daily sperm production differed between high (5.3 x 10(9)) and low nutrition (2.9 x 10(9)) bulls (P<0.001) and between Boran (4.6 x 10(9)) and Boran x Friesian (3.5 x 10(9)) bulls (P<0.01). Extragonadal sperm reserves were significantly higher in high than in low nutrition bulls (13.1 x 10(9) vs 6.9 x 10(9); P<0.001) and in Boran than Boran x Friesian bulls (12.9 x 10(9) vs 7.1 x 10(9); P<0.01). The cauda epididymis contributed 50 to 54% to the total epididymal sperm reserves. It was concluded that the plane of nutrition influenced growth rates and testes and epididymal weights, and it improved gonadal and extragonadal sperm reserves in young Boran and Boran x Friesian bulls. 相似文献
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Etotépé A. Sogbohossou Barthélémy D. Kassa Matthias Waltert Igor Khorozyan 《European Journal of Wildlife Research》2018,64(1):1
Large predators in West Africa are threatened with extinction mainly by direct and indirect effects of human activities. Within this context, intraguild competition can limit populations of some species and even play a role in extinction. In this study, we used camera trapping to assess the spatial and temporal patterns of niche partitioning between the African lion Panthera leo leo and the spotted hyena Crocuta crocuta in Pendjari Biosphere Reserve, Benin. We found that these predators are more nocturnal in the hunting zone than in the national park of the biosphere reserve. The temporal overlap between lion and hyena was high in the national park (Pianka overlap index 0.88) and low in the hunting zones (0.39). The spatial overlap was low (0.40 in the national park and 0.38 in the hunting zones). The two predators were distributed independently in the national park, but showed significant positive association (co-occurrence) in the hunting zones. We suggest that anthropogenic activities leading to depletion of predators and their prey limit lion and hyena distribution in the hunting zones to some safety areas which are strongly selected by both predators. We recommend to significantly improve conservation efforts in the hunting zones of Pendjari Biosphere Reserve and to expand research of lion-hyena intraguild relationships to improve predator survival in West Africa. 相似文献
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Josué I. Beltrán-López Andrea Romero-Maldonado Elizabeth Monreal-Escalante Bernardo Bañuelos-Hernández Luz MT Paz-Maldonado Sergio Rosales-Mendoza 《Plant cell reports》2016,35(5):1133-1141