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921.
The extensive local and regional market for traditional, handcrafted twig and grass brooms in the Bushbuckridge municipality, South Africa, provides an important means of livelihood security for several hundred poor households in the face of increasing economic hardship. Participants in this trade were a vulnerable group of middle-aged to elderly women with poor levels of education and few assets. Over half headed their own house-holds, and several came from households affected by AIDS. Entry into the broom trade was mainly a coping strategy in response to crisis, becoming long-term in the absence of alternatives. Average net annual incomes for producers and traders were modest at ZAR 2,000 and ZAR 1,000 respectively (ZAR=South African Rand), although some were earning considerably more. While unlikely to provide a way out of poverty, the trade was critical in allowing diversification and in providing a safety net, assisting poor households to overcome adversity, meet several basic needs, and educate their children.  相似文献   
922.
中国宠物商店出售的2种越南异蝎   总被引:1,自引:0,他引:1  
朱明生  杨啸风 《蛛形学报》2007,16(2):92-103
本文研究了中国宠物商店出售的产自越南南部的2种异蝎,其中1种鉴定为彼得异蝎Heterometrus petersii(Thorell,1876),另外1种系新种,命名为梁氏异蝎Heterometrus liangisp.nov.  相似文献   
923.
Sexual development in malaria parasites involves multiple signal transduction pathways mediated by reversible protein phosphorylation. Here, we functionally characterised a protein phosphatase, Ser/Thr protein phosphatase 5 (PbPP5), during sexual development of the rodent malaria parasite Plasmodium berghei. The recombinant protein phosphatase domain displayed obvious protein phosphatase activity and was sensitive to PP1/PP2A inhibitors including cantharidic acid (IC50 = 122.2 nM), cantharidin (IC50 = 74.3 nM), endothall (IC50 = 365.5 nM) and okadaic acid (IC50 = 1.3 nM). PbPP5 was expressed in both blood stages and ookinetes with more prominent expression during sexual development. PbPP5 was localised in the cytoplasm of the parasite and highly concentrated beneath the parasite plasma membrane in free merozoites and ookinetes. Targeted deletion of the pbpp5 gene had no influence on asexual blood-stage parasite multiplication or the survival curve of the infected hosts. However, male gamete formation and fertility were severely affected, resulting in almost complete blockade of ookinete conversion and oocyst development in the Δpbpp5 lines. This sexual development defect was rescued by crossing Δpbpp5 with the female defective Δpbs47 parasite line, but not with the male defective Δpbs48/45 line, thus confirming the essential function of the pbpp5 gene in male gamete fertility. Furthermore, the aforementioned PP1/PP2A inhibitors all had inhibitory effects on exflagellation of male gametocytes and ookinete conversion. In particular, endothall, a selective inhibitor of PP2A, completely blocked exflagellation and ookinete conversion at ~548.3 nM. This study elucidated an essential function of PbPP5 during male gamete development and fertility.  相似文献   
924.
We radio-tracked 15 black-backed jackals (Canis mesomelas) from 8 adjacent family groups on Benfontein Game Farm (i.e., Benfontein) in South Africa to investigate their movement patterns and social organization. Jackal family groups consisted of mated pairs (alphas), 0–3 nonbreeding adults (betas), and pups, depending on the season. Mean (±SE) home-range size of alphas (9.4 ± 1.2 km2, n = 6) did not differ (P = 0.766) from betas (9.8 ± 0.7 km2, n = 8). Most beta jackals (8 of 10) remained philopatric on Benfontein, apparently because of the high density of springbok (Antidorcas marsupialis), their preferred prey. Three of 5 alphas and all 8 betas went on extraterritorial forays (i.e., forays). Generally, betas spent more of their active time on forays (2–20% of time) than alphas (0–3%; P = 0.048), and betas went farther on forays (2–8 km) than alphas (2–3 km; P = 0.003). The number of forays differed (P < 0.001) among seasons; most forays occurred during summer (64%) when jackals visited neighboring livestock farms, apparently to predate on domestic sheep. Overall, our results indicate forays by jackals are affected by social status, seasonal availability of preferred prey, and the reproductive cycle of jackals. To reduce jackal predation on livestock farms near reserves, we recommend that preventative measures (e.g., use of herders, jackal control activities) be increased during summer when jackals are most likely to travel outside reserves. © 2019 The Wildlife Society.  相似文献   
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926.
The African Penguin Spheniscus demersus is an endangered seabird endemic to southern Africa, and killing sprees by terrestrial predators have been one of the main threats for its mainland colonies. The methods employed to manage predators may differ depending on the species involved, therefore the implementation of strategies to limit the impacts of predation relies on the correct identification of the culprit predator. We report and quantify the lesions seen in African Penguins killed by four species of terrestrial predators: Caracal Caracal caracal (52 kills), Leopard Panthera pardus (27 kills), Domestic Dog Canis lupus familiaris (10 kills), and Cape Grey Mongoose Galerella pulverulenta (4 kills). We discuss patterns of necropsy findings that can be used to identify the predator species involved. Traditional forensic methods are useful tools to direct species-specific management actions for the conservation of the African Penguin and other seabirds so that effective mitigating measures can be deployed quickly to prevent further losses. It should be borne in mind, however, that the age, size and previous hunting experience of the predator are likely to influence the pattern of lesions that will be observed, and not all carcasses will have hallmark lesions or recognisable bite marks.  相似文献   
927.
Background/Objective: Recently, several studies have reported that DNA methylation changes in tissue are reflected in blood, sparking interest in the potential use of global DNA methylation as a biomarker for gestational diabetes mellitus (GDM). This study investigated whether global DNA methylation is associated with GDM in South African women.

Methods: Global DNA methylation was quantified in peripheral blood cells of women with (n?=?63) or without (n?=?138) GDM using the MDQ1 Imprint® DNA Quantification Kit.

Results: Global DNA methylation levels were not different between women with or without GDM and were not associated with fasting glucose or insulin concentrations. However, levels were 18% (p?=?0.012) higher in obese compared to non-obese pregnant women and inversely correlated with serum adiponectin concentrations (p?=?0.005).

Discussion: Contrary to our hypothesis, global DNA methylation was not associated with GDM in our population. These preliminary findings suggest that despite being a robust marker of overall genomic methylation that offers opportunities as a biomarker, global DNA methylation profiling may not offer the resolution required to detect methylation differences in the peripheral blood cells of women with GDM. Moreover, global DNA methylation in peripheral blood cells may not reflect changes in placental tissue. Further studies in a larger sample are required to explore the candidacy of a more targeted approach using gene-specific methylation as a biomarker for GDM in our population.  相似文献   

928.
Understanding the drivers of vegetation carbon dynamics is essential for climate change mitigation and effective policy formulation. However, most efforts focus on abiotic drivers of plant biomass change, with little consideration for functional roles performed by animals, particularly at landscape scales. We combined repeat airborne Light Detection and Ranging with measurements of elephant densities, abiotic factors, and exclusion experiments to determine the relative importance of drivers of change in aboveground woody vegetation carbon stocks in Kruger National Park, South Africa. Despite a growing elephant population, aboveground carbon density (ACD) increased across most of the landscape over the 6‐year study period, but at fine scales, bull elephant density was the most important factor determining carbon stock change, with ACD losses recorded only where bull densities exceeded 0.5 bulls/km2. Effects of bull elephants were, however, spatially restricted and landscape dependent, being especially pronounced along rivers, at mid‐elevations, and on steeper slopes. In contrast, elephant herds and abiotic drivers had a comparatively small influence on the direction or magnitude of carbon stock change. Our findings demonstrate that animals can have a substantive influence on regional‐scale carbon dynamics and warrant consideration in carbon cycling models and policy formulation aimed at carbon management and climate change mitigation.  相似文献   
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930.
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