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51.
To date, only three types of full-length mariner elements have been described in ants, each one in a different genus of the Myrmicinae subfamily: Sinvmar was isolated from various Solenopsis species, Myrmar from Myrmica ruginodis, and Mboumar from Messor bouvieri. In this study, we report the coexistence of three mariner elements (Tnigmar-Si, Tnigmar-Mr, and Tnigmar-Mb) in the genome of a single species, Tapinoma nigerrimum (subfamily Dolichoderinae). Molecular evolutionary analyses of the nucleotide sequence data revealed a general agreement between the evolutionary history of most the elements and the ant species that harbour them, and suggest that they are at the vertical inactivation stage of the so-called Mariner Life Cycle. In contrast, significantly reduced levels of synonymous divergence between Mboumar and Tnigmar-Mb and between Myrmar and Botmar (a mariner element isolated from Bombus terrestris), relative to those observed between their hosts, suggest that these elements arrived to the species that host them by horizontal transfer, long after the species?? split. The horizontal transfer events for the two pairs of elements could be roughly dated within the last 2 million years and about 14 million years, respectively. As would be expected under this scenario, the coding sequences of the youngest elements, Tnigmar-Mb and Mboumar, are intact and, thus, potentially functional. Each mariner element has a different chromosomal distribution pattern according to their stage within the Mariner Life Cycle. Finally, a new defective transposable element (Azteca) has also been found inserted into the Tnigmar-Mr sequences showing that the ant genomes have been invaded by at least four different types of mariner elements.  相似文献   
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Introduction  

To use biomarkers in monitoring programmes, potential confounding factors must be considered. In the clam Scrobicularia plana, the influence of size and salinity on biomarkers at different levels of biological organisation has been examined.  相似文献   
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Brian D'Silva  Olivia Tecosky 《Disasters》2007,31(S1):S124-S138
The signing of the Comprehensive Peace Agreement (CPA) in Sudan has created a new opportunity for peace. Approaches to food security must now be reoriented based on the agro-ecological diversity in Sudan. WFP is in a unique position to catalyse an approach to food security that meets immediate needs and contributes to long-term recovery, in collaboration with the Government of National Unity (GNU) and the Government of South Sudan (GOSS). Aggregate food production in Sudan has increased in the past decade. At sub-regional levels, however, many areas remain food insecure. Major research must be undertaken to identify optimum levels of food production and barriers to access to food at sub-regional levels as a first step towards linking deficit areas with areas of surplus. Initiatives must also be undertaken to facilitate increased integration between sub-regions. Increased sub-regional linkages could ensure more efficient delivery of food in the short term as well as recovery and economic growth in the long term.  相似文献   
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Engineered nano-sized Cu oxide particles are extensively used in diverse applications. Because aquatic environments are the ultimate “sink” for all contaminants, it is expected that nanoparticles (NP) will follow the same fate. In this study, two marine invertebrates Scrobicularia plana and Hediste diversicolor were chosen as ecotoxicological models. The aim was to evaluate behavioural (burrowing kinetics, feeding rate) and biochemical (biomarkers) responses of S. plana and H. diversicolor exposed in the laboratory to Cu (10 μg L−1) added in natural seawater either in the form of engineered nanoparticles (NPs) of CuO or as dissolved Cu in 2% HNO3. Exposure was characterized by considering (i) the physico-chemical fate of NP (ii) the fraction of labile Cu in experimental media and (iii) Cu bioaccumulation. Results showed high aggregation of CuO NPs in seawater and no additional bioavailable Cu concentrations. Behavioural impairments were observed in S. plana exposed to CuO NPs or soluble Cu whereas in H. diversicolor, only the exposure to soluble Cu led to a burrowing decrease. No obvious neurotoxicity effects were revealed since in both species, no changes in cholinesterasic activity occurred in response to both forms of Cu exposure. Biomarkers of oxidative-stress catalase and glutathione-S-transferase were enhanced in both species whereas superoxide dismutase was increased only in S. plana exposed to CuO NPs. Metallothionein-like protein was increased in bivalves exposed to both forms of Cu. Since, no detectable release of soluble Cu from CuO NPs occurred during the time of experiment, ecotoxicity effects seem to be related to CuO NPs themselves.  相似文献   
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Olivia Wilkinson 《Disasters》2018,42(3):459-474
While other works have analysed what constitutes a faith‐based approach, this study examines what values and practices are employed in a secular approach to disaster response in communities where religion matters. Evidence of a secular approach is assessed in the context of the disaster response to Typhoon Haiyan (2013) in the Philippines, a country in which more than 90 per cent of the population identify themselves as religious. Using interviews with staff members of non‐governmental organisations (NGOs) and focus groups composed of beneficiaries, this paper provides an overview of how respondents commonly characterise a secular approach to disaster response. Results indicate differing NGO and beneficiary opinions on interaction over efficiency and the impartiality and neutrality of organisations. Secularity had a distinct effect on the disaster response to Haiyan, mostly by creating boundaries vis‐à‐vis when and where religion was permitted in the secularised humanitarian system. An awareness of these effects is encouraged to improve interaction with affected populations and local organisations.  相似文献   
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Regional Environmental Change - This paper reviews the current knowledge of climatic risks and impacts in South Asia associated with anthropogenic warming levels of 1.5–4 °C...  相似文献   
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We augment discussions about the Good Environmental Status of the North Sea by developing two extreme visions and assessing their societal benefits. One vision (‘Then’) assumes restoration of benthic functioning; we contend that trawling had already degraded the southern North Sea a century ago. Available information is used to speculate about benthic functioning in a relatively undisturbed southern North Sea. The second vision (‘Now’) draws on recent benthic functioning. The supply of five ecosystem services, supported by benthic functioning, is discussed. ‘Then’ offers confidence in the sustainable supply of diverse services but restoration of past function is uncertain and likely to be paired with costs, notably trawling restraints. ‘Now’ delivers known and valued services but sustained delivery is threatened by, for example, climate change. We do not advocate either vision. Our purpose is to stimulate debate about what society wants, and might receive, from the future southern North Sea.

Electronic supplementary material

The online version of this article (doi:10.1007/s13280-014-0536-5) contains supplementary material, which is available to authorized users.  相似文献   
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