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1.
Paul D. Spencer Anne B. Hollowed Michael F. Sigler Albert J. Hermann Mark W. Nelson 《Global Change Biology》2019,25(11):3954-3971
Trait‐based climate vulnerability assessments based on expert evaluation have emerged as a rapid tool to assess biological vulnerability when detailed correlative or mechanistic studies are not feasible. Trait‐based assessments typically view vulnerability as a combination of sensitivity and exposure to climate change. However, in some locations, a substantial amount of information may exist on system productivity and environmental conditions (both current and projected), with potential disparities in the information available for data‐rich and data‐poor stocks. Incorporating this level of detailed information poses challenges when conducting, and communicating uncertainty from, rapid vulnerability assessments. We applied a trait‐based vulnerability assessment to 36 fish and invertebrate stocks in the eastern Bering Sea (EBS), a data‐rich ecosystem. In recent years, the living marine resources of the EBS and Aleutian Islands have supported fisheries worth more than US $1 billion of annual ex‐vessel value. Our vulnerability assessment uses projections (to 2039) from three downscaled climate models, and graphically characterizes the variation in climate projections between climate models and between seasons. Bootstrapping was used to characterize uncertainty in specific biological traits and environmental variables, and in the scores for sensitivity, exposure, and vulnerability. The sensitivity of EBS stocks to climate change ranged from “low” to “high,” but vulnerability ranged between “low” and “moderate” due to limited exposure to climate change. Comparison with more detailed studies reveals that water temperature is an important variable for projecting climate impacts on stocks such as walleye pollock (Gadus chalcogrammus), and sensitivity analyses revealed that modifying the rule for determining vulnerability increased the vulnerability scores. This study demonstrates the importance of considering several uncertainties (e.g., climate projections, biological, and model structure) when conducting climate vulnerability assessments, and can be extended in future research to consider the vulnerability of user groups dependent on these stocks. 相似文献
2.
Leading invasion biologists sometimes dismiss critics and criticisms of their field by invoking “the straw man” fallacy. Critics of invasion biology are also labelled as a small group of “naysayers” or “contrarians”, who are sometimes engaging in “science denialism”. Such unfortunate labels can be seen as a way to possibly suppress legitimate debates and dismiss or minimize reasonable concerns about some aspects of invasion biology, including the uncertainties about the geographic origins and complex environmental impacts of species, and the control programs against species perceived as “invasive”. In assessing the quality of the debate in this area, we examine the validity of the use of various strategies, including the “straw man” concept, and explore a range of potential logical fallacies present in some recent prominent discussions about invasion biology and so-called “invasive” species. The goal is to add some clarity to the concepts involved, point out some problematic issues, and improve the quality of the debates as the discussions move forward. 相似文献
3.
Drug dependence is a serious health and social problem. Social factors can modify vulnerability to developing drug dependence, acting as risk factors or protective factors. Whereas stress and peer environment that encourage substance use may increase drug taking, strong attachments between family members and peer environment that do not experience drug use may protect against drug taking and, ultimately, drug dependence. The rewarding effects of drug abuse and social interaction can be evaluated using animal models. In this review we focus on evaluating social interaction reward in the conditioned place preference paradigm. We give an overview of how social interaction, if made available within the drug context, may facilitate, promote and interact with the drug’s effects. However, social interaction, if offered alternatively outside the drug context, may have pronounced protective effects against drug abuse and relapse. We also address the importance of the weight difference parameter between the social partners in determining the positive or “agonistic” versus the hostile or “antagonistic” social interaction. We conclude that understanding social interaction reward and its subsequent effects on drug reward is sorely needed for therapeutic interventions against drug dependence. 相似文献
4.
Christopher Courtheyn 《Ethnic and racial studies》2013,36(15):2641-2660
Despite the institution of multicultural policies and pluriethnic governments across Latin America, racist violence against Indigenous and Afro-descendant groups persists. Yet the racial facets of violence against non-ethnic campesinos remain unexplored. Integrating scholarship on race as a global structure and Latin American racial formations, I offer an account of racialization in Colombia. This article analyzes the racial dynamics of resistance to extractivism in Colombia's Campesino University, uniting Indigenous and campesino groups like the San José de Apartadó Peace Community. While the dominant race lexicon separates “campesinos” like San José's peasants from “Indigenous” and “Black” groups, I argue that the identifier campesino mestizo hides how San José's farmers were “de-indigenized” yet remain racialized as the less-than-human “Indigenous savage”. If racialization works to dominate but also divide the subaltern, then Campesino University participants’ cross-ethnic solidarity network against what they affirm is a shared experience of racist violence both unveils and counters racism. 相似文献
5.
This paper uses semi-structured interviews with Ecuadorian “white mestizos” of the upper classes to provide insights into the nature of racism in Ecuador. Interview data illuminate the specifics of racism and discrimination suffered by some of those labelled as mestizos, demolishing anew the idea of a homogenous mestizaje. Longo and cholo emerge as specific ethnic terminology used to create a racial/class distinctions among mestizos struggling for ethnoracial capital in a newly defined plurinational and intercultural state. These findings are contrasted with recent progressive state policies that address the plight of groups historically marginalized or ignored by the Ecuadorian narrative of mestizaje, but fail to look within mestizaje to battle against the remnants of colonial constructions of power and difference. 相似文献
6.
Assessing household livelihood vulnerability to climate change: The case of Northwest Vietnam 总被引:1,自引:0,他引:1
This study applied livelihood vulnerability index (LVI) and livelihood effect index (LEI) to assess vulnerability from climate variability and change of three agricultural and natural resources dependent commune in northwest Vietnam, a country that is expected to bear some of the most severe impacts of climate change. Based on a survey of 335 farm household data, complemented with secondary data on climate factors, a composite index was calculated and differential vulnerabilities were compared. The results of the analysis suggest that one of the communities, “Pa Vay Su,” was more vulnerable than the others, particularly in relation to housing, knowledge and skills, socio-demographics, health and water security, social networks, and livelihood strategy. “Hien Luong” commune, on the other hand, was more vulnerable in relation to other LVI indicators with the exception of food security, climate variability, and natural disasters. “Moc Chau” community was more vulnerable in relation to water security, social demographic than Hien Luong commune. Overall, the article shows that three different vulnerability assessment indices can be broadly applied in comparable setting in other areas of country and they could usefully establish the basis for a nationally applicable index to identify and prioritize adaptation and mitigation needs. 相似文献
7.
Daniel H. de Vries 《Human ecology: an interdisciplinary journal》2017,45(4):437-448
After major flooding associated with Hurricane Floyd (1999) in North Carolina, mitigation managers seized upon the “window of opportunity” to woo residents to accept residential buyout offers despite sizable community resistance. I present a theoretical explanation of how post-crisis periods turn into “opportunities” based on a temporal referential theory that complements alternative explanations based on temporal coincidence, panarchy, and shock-doctrine theories. Results from fieldwork conducted from 2002 to 2004 illustrate how several temporal influences compromised collective calibration of “normalcy” in local cultural models, leading to an especially heightened vulnerability to collective surprise. Four factors particularly influenced this temporal vulnerability: 1) epistemological uncertainty of floodplain dynamics due to colonization; 2) cultural practices that maintained a casual amnesia; 3) meaning attributed to stochastic timing of floods; and 4) competitive impact of referential flood baseline attractors. 相似文献
8.
It is well established that during muscle regeneration, the satellite cells which are in a state of mitotic arrest, can initiate cell division to produce myoblasts which subsequently fuse to form myotubes. However, whether myonuclei, contained within damaged myotubes, or “freed” as a result of the trauma, play any role in muscle regeneration remains unresolved. In myogenic cultures, it is possible to obtain renewed myogenesis when initial cultures are sub-cultured. The aim of this study, was to obtain evidence of the participation by myonuclei of primary cultures in myogenesis which occurs subsequently in secondary cultures. In culture, myonuclei can be labelled with H3-thymidine and their ultimate fate, either as “free” myonuclei or myonuclei associated with disrupted myotubes can be followed unequivocally. Three types of experiments are performed: (i) Primary myogenic cultures containing only myotubes are subcultured. (ii) Primary myogenic cultures containing myotubes with labelled myonuclei are disrupted and subcultured. (iii) Primary myogenic cultures containing myotubes with unlabelled myonuclei are mixed with labelled mononucleated myogenic cells and sub-cultured. In all instances no evidence of myogenesis from myonuclei is obtained. It is concluded that myonuclei, which were rendered postmitotic during myogenesis, remain so when muscle is disrupted and cannot re-enter the mitotic cycle. 相似文献
9.
Adam Hochman 《Ethnic and racial studies》2013,36(8):1245-1262
This paper defends the concept of racialization against its critics. As the concept has become increasingly popular, questions about its meaning and value have been raised, and a backlash against its use has occurred. I argue that when “racialization” is properly understood, criticisms of the concept are unsuccessful. I defend a definition of racialization and identify its companion concept, “racialized group.” Racialization is often used as a synonym for “racial formation.” I argue that this is a mistake. Racial formation theory is committed to racial ontology, but racialization is best understood as the process through which racialized – rather than racial – groups are formed. “Racialization” plays a unique role in the conceptual landscape, and it is a key concept for race eliminativists and anti-realists about race. 相似文献
10.
Cameron Buckner 《Biology & philosophy》2013,28(1):145-152
Povinelli and colleagues ask whether chimpanzees can understand the concept of weight, answering with a resounding “no”. They justify their answer by appeal to over thirty previously unpublished experiments. I here evaluate in detail Povinelli’s arguments against his targets, questioning the assumption that such comparative questions will be resolved with an unequivocal “yes” or “no”. 相似文献
11.
THE rare existence of organ-specific antisera transcending species differences was pointed out by Coombs1. Similar new organ, or “erythrocyte-specific”, antisera reacting selectively to the erythrocytes of several species of Myomorpha are described here. The antisera, “anti-A”, were prepared by the method of Adachi and Furusawa2: adult guinea-pigs were sensitized with the “antigen-A” (the protein portion of dd mouse erythrocyte membrane). The detailed procedure for preparing labelled antibody, the staining method and its specific reactivity to mouse erythrocytic cells have been reported before3. Circulating erythrocytes from various animals were stained with the fluorescein isothiocyanate-labelled “anti-A”. Smeared cell preparations were fixed with acetone at ? 20° C for 20 min and incubated with the labelled antisera, which had been thoroughly absorbed with the emulsion of mouse liver and kidney to remove the cross-reacting antibodies, at 37° C for 90 min. A light microscope with a darkfield condenser was used for the fluorescent observations using Orsen's interference filter system. Clear fluorescent reactions, though of varied intensities, were observed with those animals classified as Myomorpha, that is, mouse, rat, golden hamster and Chinese hamster (Table 1, Fig. 1). Mammalian erythrocytes other than those of the guinea-pig used as the sensitized animal showed faint fluorescences. Nucleated erythrocytes of the chick, quail, turtle, toad and goldfish were negative to the reaction. The erythrocyte-specific reactivity of the labelled antisera was examined with the liver, kidney and thymus cells of the animals whose erythrocytes displayed intense fluorescences; they showed, however, no fluorescence. 相似文献
12.
Heidi Armbruster 《Ethnic and racial studies》2013,36(15):2680-2699
This article examines the “Syrian Vulnerable Persons Resettlement Programme” (SVPRP) as a specific British response to the “European refugee crisis”. Based on an analysis of media reporting (2014–17) and empirical evidence from agencies and volunteers tasked with implementing the programme, this essay reveals the ethical and political ambiguities at its heart. By focusing on the notion of “vulnerability” I argue that the humanitarian configuration of a refugee worthy of care is implicated in two significant practices: exceptionalising a small group of Syrians as legitimate targets for compassion and constructing compassion itself as a rationed resource in a climate of anti-immigrant hostility, austerity and Brexit. 相似文献
13.
Matthew A. Hale 《Dialectical Anthropology》2013,37(1):51-82
New Rural Reconstruction is an ongoing alternative development movement in China, with ties to transnational movements for “social economy,” “fair trade,” and “food sovereignty.” It consists of a diverse network of organizations and projects loosely united by the goals of reversing the rural-to-urban flow of resources and (re)constructing sustainable, self-sufficient communities based on cooperation among peasant households, supported by agroecological skill-sharing and alternative marketing. This article examines four peasant organizations in this movement, focusing on their efforts to negotiate the contradictions between their ideals and their relation to capitalism. I argue that, under present conditions, “success” at reversing the flow of resources through commercial means tends to require further integration into capitalist processes, both increasing vulnerability to global economic forces and undermining “alternative” ideals such as equality, sustainability, and participatory democracy. I thus engage critically with the interdisciplinary literature on “social economy” and cooperatives, considering how cooperative experiments might move beyond the limits of alternativism to play a role in the transformation of their socioeconomic context. 相似文献
14.
Zhiwei Xu Perry E. Sheffield Hong Su Xiaoyu Wang Yan Bi Shilu Tong 《International journal of biometeorology》2014,58(2):239-247
Young children are thought to be particularly sensitive to heat waves, but relatively less research attention has been paid to this field to date. A systematic review was conducted to elucidate the relationship between heat waves and children’s health. Literature published up to August 2012 were identified using the following MeSH terms and keywords: “heatwave”, “heat wave”, “child health”, “morbidity”, “hospital admission”, “emergency department visit”, “family practice”, “primary health care”, “death” and “mortality”. Of the 628 publications identified, 12 met the selection criteria. The existing literature does not consistently suggest that mortality among children increases significantly during heat waves, even though infants were associated with more heat-related deaths. Exposure to heat waves in the perinatal period may pose a threat to children’s health. Pediatric diseases or conditions associated with heat waves include renal disease, respiratory disease, electrolyte imbalance and fever. Future research should focus on how to develop a consistent definition of a heat wave from a children’s health perspective, identifying the best measure of children’s exposure to heat waves, exploring sensitive outcome measures to quantify the impact of heat waves on children, evaluating the possible impacts of heat waves on children’s birth outcomes, and understanding the differences in vulnerability to heat waves among children of different ages and from different income countries. Projection of the children’s disease burden caused by heat waves under climate change scenarios, and development of effective heat wave mitigation and adaptation strategies that incorporate other child protective health measures, are also strongly recommended. 相似文献
15.
Walking back the cat: Unsupervised classification as an aid in “remote” fossil prospecting
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Glenn C. Conroy 《Evolutionary anthropology》2014,23(5):172-176
Counterintelligence analysts use a technique called “walking back the cat'' to reveal “moles” or others passing on disinformation in which they compare what they now know as fact against what their agents or informers had told them to expect about certain persons or events. 1 Thus, “walking back the cat” is a perfect metaphor for working backwards; that is, retracing the complex development of an event and examining the “run up” to it in order to gain useful insights about how that event unfolded. Perhaps paleoanthropology can profit from such an approach. 相似文献
16.
《Harmful algae》2014
The detection of dense harmful algal blooms (HABs) by satellite remote sensing is usually based on analysis of chlorophyll-a as a proxy. However, this approach does not provide information about the potential harm of bloom, nor can it identify the dominant species. The developed HAB risk classification method employs a fully automatic data-driven approach to identify key characteristics of water leaving radiances and derived quantities, and to classify pixels into “harmful”, “non-harmful” and “no bloom” categories using Linear Discriminant Analysis (LDA). Discrimination accuracy is increased through the use of spectral ratios of water leaving radiances, absorption and backscattering. To reduce the false alarm rate the data that cannot be reliably classified are automatically labelled as “unknown”. This method can be trained on different HAB species or extended to new sensors and then applied to generate independent HAB risk maps; these can be fused with other sensors to fill gaps or improve spatial or temporal resolution. The HAB discrimination technique has obtained accurate results on MODIS and MERIS data, correctly identifying 89% of Phaeocystis globosa HABs in the southern North Sea and 88% of Karenia mikimotoi blooms in the Western English Channel. A linear transformation of the ocean colour discriminants is used to estimate harmful cell counts, demonstrating greater accuracy than if based on chlorophyll-a; this will facilitate its integration into a HAB early warning system operating in the southern North Sea. 相似文献
17.
W H Kunau 《Chemistry and physics of lipids》1973,11(4):254-269
This article reviews synthetic routes leading to polyunsaturated fatty acids having “skipped” double bonds. Emphasis is placed on the “acetylenic approach”.The suitability of building blocks, their condensation reactions as well as the controlled reduction of triple bonds to cis double bonds are discussed. In addition, the application of the various methods to the preparation of polyunsaturated fatty acids labelled with 3H and/or 14C at distinct positions of the molecules is reviewed. 相似文献
18.
Guillermo Quindós María Villar-Vidal Elena Eraso 《Revista iberoamericana de micología》2009,26(1):49-55
BackgroundMost recalcitrant infections are associated to colonization and microbial biofilm development. These biofilms are difficult to eliminate by the immune response mechanisms and the current antimicrobial therapy.AimTo describe the antifungal of micafungin against fungal biofilms based in the scientific and medical literature of recent years.MethodsWe have done a bibliographic retrieval using the scientific terms “micafungin”, “activity”, “biofilm”, “Candida”, “Aspergillus”, “fungi”, “mycos”*, susceptibility, in PubMed/Medline from the National Library of Medicine from 2006 to 2009.ResultsMost current antifungal agents (amphotericin B and fluconazole) and the new azole antifungals have no activity against fungal biofilms. However, micafungin and the rest of echinocandins are very active against Candida albicans, Candida dubliniensis, Candida glabrata, and Candida krusei biofilms but their activities are variable and less strong against Candida tropicalis and Candida parapsilosis biofilms. Moreover, they have not activities against the biofilms of Cryptococcus y Trichosporon.ConclusionsThe activity of micafungin against Candida biofilms gives more strength to its therapeutic indication for candidaemia and invasive candidiasis associated to catheter, prosthesis and other biomedical devices. 相似文献
19.
Activation of Thymus Cells by Histocompatibility Antigens 总被引:22,自引:0,他引:22
“Educated” or “activated” thymus cells have been shown, by the use of “strong” histocompatibility antigens, to be immunocompetent only against the antigens by which they were originally activated. 相似文献
20.
Within the Asteridae (“Sympetalae Tetracyclicae”) two main developmental patterns can be distinguished as regards the formation of corolla tubes, namely “early” and “late sympetaly”. Since the character “ontogeny of sympetaly”, after intensive studies, proved to be valuable for systematic considerations, we now recognize two blocks of orders within the Asteridae (and related groups): the Asteridae A-block and the Asteridae B-block (Figs. 82 and 83). By and large this bipartition referring mainly to the corolla tube development corresponds well with major lineages indentified by recent molecular data (see, e.g., Chase et al., 1993). Asteridae A-block is characterized predominantely by “late sympetaly” the “early sympetaly” in Rubiales and Oleales can be interpreted as derived within this block or can be linked with that in Asteridae B-block. Asteridae B-block is uniform throughout in its “early sympetaly”. In this block it is a primitive character, as judged from its occasional occurrence in the choripetalous Cornales and Apiales (Apiaceae, Araliaceae, Pittosporaceae), which can be regarded as ancestral for block B. 相似文献