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321.
Felix J. Mkonyi Anna B. Estes Maurus J. Msuha Laly L. Lichtenfeld Sarah M. Durant 《Human Dimensions of Wildlife》2017,22(4):314-330
We conducted 300 semi-structured interviews with local people adjacent to Tarangire National Park, northern Tanzania, to determine their attitudes and perceptions toward large carnivores. We analyzed the relationships between attitudes and age, gender, education, occupation, years at residence, income, distance from protected area, livestock owned, livestock lost to predators and knowledge of carnivores. Three-quarters of respondents (79%) held negative attitudes toward large carnivores, while 20% were generally positive. Three variables were positively associated with attitudes towards different species: formal education (all carnivore species), years at residence (lions and cheetahs), and knowledge of carnivores (cheetahs). Attitudes toward large carnivores were not significantly related to distance from protected area, livestock owned. or livestock lost to predators. Findings suggested that interventions aimed at fostering positive attitudes toward large carnivores should focus on improving formal education and securing long-term residency for people in the region. 相似文献
322.
R. C. Siqueira S. C. Rahal L. R. Inamassu M. J. Mamprim M. Felix M. S. Castilho L. R. Mesquita V. L. Ribeiro C. R. Teixeira F. B. Rassy 《Anatomia, histologia, embryologia》2017,46(6):572-581
This study describes the osteology and radiology of the pelvic limb in maned wolves. Ten (five live and five dead) maned wolves (Chrysocyon brachyurus), five males and five females, aged from 2 to 7 years old were used. Digital radiographs were taken and recorded for both pelvic limbs in all animals. Osteology was correlated with the radiographic images. The pelvis had a rectangular shape, and the obturator foramen (foramen obturatum) was oval. The femoral neck (collum femoris) was short and thick. The greater trochanter (trochanter major) extended proximally to near the dorsum of the femoral head (caput ossis femoris). The lateral femoral condyle (condylus lateralis) was larger than the medial condyle (condylus medialis), and the intercondylar fossa (fossa intercondylaris) had a slightly oblique orientation. The proximal tibia displayed medial and lateral condyles with the medial larger. The femur was slightly shorter than the tibia. Seven tarsal bones (ossa tarsi) were present, four long metatarsal bones (ossa metatarsalia II ‐ V) and a short first metatarsal bone (os metatarsal I). 相似文献
323.
324.
Sanjay?K.?JaiswalEmail author Judith?Naamala Felix?D.?DakoraEmail author 《Biology and Fertility of Soils》2018,54(3):309-318
Recent findings on the effect of aluminium (Al) on the functioning of legumes and their associated microsymbionts are reviewed here. Al represents 7% of solid matter in the Earth’s crust and is an important abiotic factor that alters microbial and plant functioning at very early stages. The trivalent Al (Al3+) dominates at pH <?5 in soils and becomes a constraint to legume productivity through its lethal effect on rhizobia, the host plant and their interaction. Al3+ has lethal effects on many aspects of the rhizobia/legume symbiosis, which include a decrease in root elongation and root hair formation, lowered soil rhizobial population, and suppression of nitrogen metabolism involving nitrate reduction, nitrite reduction, nitrogenase activity and the functioning of uptake of hydrogenases (Hup), ultimately impairing the N2 fixation process. At the molecular level, Al is known to suppress the expression of nodulation genes in symbiotic rhizobia, as well as the induction of genes for the formation of hexokinase, phosphodiesterase, phosphooxidase and acid/alkaline phosphatase. Al toxicity can also induce the accumulation of reactive oxygen species and callose, in addition to lipoperoxidation in the legume root elongation zone. Al tolerance in plants can be achieved through over-expression of citrate synthase gene in roots and/or the synthesis and release of organic acids that reverse Al-induced changes in proteins, as well as metabolic regulation by plant-secreted microRNAs. In contrast, Al tolerance in symbiotic rhizobia is attained via the production of exopolysaccharides, the synthesis of siderophores that reduce Al uptake, induction of efflux pumps resistant to heavy metals and the expression of metal-inducible (dmeRF) gene clusters in symbiotic Rhizobiaceae. In soils, Al toxicity is usually ameliorated through liming, organic matter supply and use of Al-tolerant species. Our current understanding of crop productivity in high Al soils suggests that a much greater future accumulation of Al is likely to occur in agricultural soils globally if crop irrigation is increased under a changing climate. 相似文献
325.
Victor Akwu Otene Jacqueline A. C. Ezihe Felix S. Torgenga 《Journal Of Agricultural & Food Information》2018,19(2):141-148
This study assessed the usage of mobile phones among farmers in the Keana Local Government Area of Nasarawa State, Nigeria. One hundred and fifty-eight respondents were selected using purposive and random sampling techniques. Primary data were used, and collected using a structured questionnaire. Research revealed that a majority of the respondents (60.1%) had a medium level of use of mobile phones. The mobile phone network preferred by respondents was MTN (32.3%). The major factor affecting the use of mobile phones is poor network coverage (22.1%). Possession of formal education, income, and sex of the respondents significantly affected their level of use of mobile phones. It is therefore recommended that network providers be supervised by the Government to ensure quality service delivery, and other network providers encouraged to improve on their services. 相似文献
326.
Pitch canker on plantation-grown Pinus species, caused by the fungal pathogen Fusarium circinatum, first appeared in the western and southern Cape regions of South Africa. However, outbreaks have subsequently been reported from the major plantation growing regions of KwaZulu-Natal and Limpopo in the eastern, summer rainfall regions of the country. It is more than 10 years since the last detailed population genetics studies on F. circinatum in the region were conducted. To shed light on the population biology of F. circinatum in this region of South Africa, we used microsatellite markers and mating-type assays to study a collection of 296 isolates from different nurseries and plantation sites. Our results showed that populations in the region are highly diverse, but strongly interconnected, with various genotypes shared across nursery and plantation collection sites. In contrast to nursery populations, those associated with pitch canker outbreaks were characterized by the presence of relatively small numbers of dominant genotypes that were generally widespread across the region. Opposite mating-type individuals occurred in most of the isolate collections, but multilocus linkage disequilibrium analyses pointed towards clonality being the main reproductive mode of F. circinatum in the region. Most of the pathogen's genetic variation could probably have resulted from multiple different introductions into the country and more specifically, into the summer rainfall region. Because the spread and establishment of invasive pathogens are typically driven by aggressive clones, the results of this study provide important considerations for current and future Pinus disease management strategies. 相似文献