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The availability of food, and hence energy, is known to influence the abundance, habitat choice and growth of individuals. In contrast, there is a paucity of knowledge on how the interaction of energy supply and social status determines patterns of residency and movement. This study tests whether the presence of conspecifics and an individual’s social status in relation to food supply influence the fitness and movement of a drift-feeding fish (Galaxias fasciatus). Using an information-theoretic approach (AIC), our analysis indicated that the most parsimonious model of fish movement among pools was one that included food supply, social rank and fish relative growth rate. Our results indicated that subordinate fish relocated more frequently compared to dominant fish, most likely as a consequence of intra-specific competition that limited the access of these smaller fish to resources and constrained their growth. Our results suggest that energy constraints may force individuals to explore new habitats in an effort to find more energetically profitable patches. We conclude that intra-specific competition mediated through the social hierarchy amongst closely interacting individuals plays a key role in determining individual growth, residency and relocation.  相似文献   

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The cycle of duplication and division, known as the cell cycle, is the essential mechanism by which all living organisms reproduce. This activity allows students to develop an understanding of the main events that occur during the typical eukaryotic cell cycle mostly in the process of mitotic phase that divides the duplicated genetic material creating two genetically identical daughter cells.  相似文献   

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The morphological, molecular and pathological characters of 34 isolates identified as Ascochyta pinodes, A. phaseolorum, and Phoma medicaginis var. pinodella were determined. Initial molecular findings, based on PCR fragment size and RFLPs of sections of the mitochondrial genome, the rRNA gene cluster and the beta-tubulin gene complex, were further investigated by sequencing of the total rRNA ITS regions. Isolates were homogenous for all characteristics determined, with the exception of conidial size and septation, and RFLPs of AT rich (presumptive mitochondrial) DNA. The results suggest that the isolates represent host preferential forms of a single taxon, and this finding is discussed in relation to the known teleomorphs and reference material of the species studied.  相似文献   

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As neoliberalism continues to influence environmental governance, it affects notions about the appropriate level of community involvement in resource management. Under more recent iterations, hybrid forms of governance are emphasized, including government–civil society partnerships and approaches geared towards harnessing the strengths of local communities. Here we explore the characteristics of different resource management rights, strategies, and tools through which communities can find political space to assert their own agendas within a neoliberalized policy environment. We examine the successful use of some of these approaches by communities during the initial development of community forests policy and practice in British Columbia, Canada. While we confirm the complex, contingent and case-specific nature of opportunities for comanagement created through neoliberal policy elements, we suggest that space does exist for community forest bodies to assert local values, goals and strategies, demonstrating the creativity, ingenuity and determination of communities to attain a real voice in management.
Evelyn PinkertonEmail:
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Aadhaar (literally ‘foundation’) is the largest national biometric identification drive the world has witnessed. An Aadhaar is a twelve-digit ID number linked to its holder's iris scans, fingerprints, facial photograph, and demographic information in a centralized database. In but a decade, India has expeditiously enrolled over 90 per cent of its billion-strong population into a Central Identities Data Repository. This essay is an ethnographic consideration of the processes by which Aadhaar enrollees become data, focusing on the sociopolitical valence of biometric data. It argues that the datafication of the body via Aadhaar occasions re-examinations of – and contestations over – the idea of the individual in postcolonial India, a country often deemed sociocentric in popular and scholarly discourse alike. Further, it suggests that biometric socialization facilitates belonging in a ‘Digital India’, often rendered as a data cosmopolis in emergent technocratic imaginations.  相似文献   

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The concepts of biocitizenship and biosociality, in many ways developed as a reaction to the former critique of genetification and fears of a return of eugenics, have gained a stronghold in much of the current debates on the social effects of modern-day genetics. In contrast to claims of a return to eugenics, the literature on biocitizenship highlights the new choice-enhancing possibilities involved in present-day biomedicine, underlining the break with past forms of biopower. In this analysis, hope becomes a life-inducing and vitalizing force, opening new avenues of civic participation and engagement. Most critics of this analysis have attacked the claims to novelty attributed to these concepts, arguing that more traditional forms of biopower remain as important as ever. In contrast, we argue that the biocitizenship literature underestimates the radical nature of this break with the past, ending up with a too narrow and one-sided interpretation of the ramifications of the new discourse of hope. On the basis of two different case stories, the “Portraits of Hope” campaign from California, USA and the “Mehmet Case” from Norway, we indicate an alternative “darker” reading of the new discourse of hope, arguing that its driving force is not so much future possibilities as present despair.  相似文献   

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What we consider “nature” is always historical and relational, shaped in contingent configurations of representational and social practices. In the early twentieth century, the English ecologist A.G. Tansley lamented the pervasive problem of international misunderstandings concerning the nature of “nature.” In order to create some consensus on the concepts and language of ecological plant geography, Tansley founded the International Phytogeographical Excursion, which brought together leading plant geographers and botanists from North America and Europe. The first IPE in August 1911 started with the Norfolk Broads. It was led by Marietta Pallis, Tansley’s former student at Cambridge. This trip and the work of Pallis, neglected in other accounts of this early period of the history of ecology, influenced the relations between Tansley and important American ecologists H.C. Cowles and F.E. Clements. Understanding “place” as a network of relations, our regional focus shows how taking international dialogue, travel and interchange into account enriches understanding of ecological practice.  相似文献   

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Komissarov  I. V. 《Neurophysiology》2004,36(2):148-159
Modern concepts on the dependence of the efficacy of glutamatergic synaptic transmission on the subunit structure of glutamate (Glu) receptors and their chemical surroundings are described and discussed in the review. The above surroundings can significantly modulate the affinity of these receptors and/or change their number. Peculiarities of the effects exerted by different components of such surroundings (allosteric modulators, redox-active substances, some ions, hormones, etc.) on Glu receptors are analyzed. In the light of the chemical soup concept, the effects of Glu receptor ligands on the cognitive activity of experimental animals and of humans are discussed.  相似文献   

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This essay argues that stable, heritable, habituated semiotics on one scale of life allows for opportunism, origination, and the solving of novel problems on others. This is grounded in how interpretation is neither caused nor determined by its object, such that success at interpretation simply cannot be defined by any comparison between an interpretation and its object. Rather, an interpretation is a reciprocated incorporation of a living thing and its environment, and successful if it furthers the living, interpreting thing. By applying biosemiotic theory to seemingly disparate studies of parasitic infections (Jaroslav Flegr), autonomic nervous systems (Stephen Porges), and social change (Charles Tilly) as well as the classical pragmatic notion that biology, psychology and sociology are disparate approaches to the singular, radically continuous, and perennial question of who (or what) am I (Dewey, James, Mead). I argue that the distinction (e.g.,) between voluntary and autonomic behavior is but a ghost of older dualisms, the pseudo-contradictions of matter v. mind, body v. soul, but also self v. not self. Moreover, all such pseudo-contradictions (individual v. social, sensation v. response, parasite v. host, and etc.) are resolved as scale thick, self-similar examples of semiotic transaction wherein degeneration or habituation on one scale of life allows for generative or novel interaction on another.  相似文献   

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Witdraai is home to a few hundred ≠Khomani who resettled there after the successful land claim of 1999. In all, the first phase of their claim granted them ownership of six farms totaling about 40,000 hectares of land. Before this restitution, the Bushmen had been an “Other-diaspora” dispersed by the forces of apartheid and colonialism. Being a small settlement in the vast Kalahari in Northern Cape Province, close to the Botswana border, Witdraai is rarely a cartographic highlight where the province’s main towns, cities and localities are concerned. For over a decade the ≠Khomani have been involved in trying to find solutions to the problem of appropriate development of the six farms for sustainable communal benefit. Alcohol abuse among many of the residents, however, seems to be complicating the search for lasting solutions. This article uses visual stills, collected during the 2011 trip to the Kalahari by University of KwaZulu–Natal researchers from the Centre for Communication, Media and Society (CCMS), to investigate alcohol use/abuse amongst some of the people living at or near Witdraai. The article applies “cultural mapping” of a different sort, focusing selectively on visual traces of the corporeal existence of “alcohol” in the sand-dune landscape of Witdraai against a backdrop of commercial tourist branding of the landscape.  相似文献   

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This paper addresses and challenges the pronatalist marginalization and oppression of voluntarily childless women in the Global North. These conditions call for philosophical analyses and for sociopolitical responses that would make possible the necessary moral spaces for resistance. Focusing on the relatively privileged subgroups of women who are the targets of pronatalist campaigns, the paper explores the reasons behind their choices, the nature and methods of Western pronatalism, and distinguishes three specific sources of some of the more lasting, and stigmatizing attacks: popular culture, law and policy, and medicine itself. I then argue that because they are construed by motherhood-essentializing, and increasingly popular, pronatalist narratives as, among other things, “failed” or “selfish,” voluntarily childless women are subsequently burdened with damaged identities that can leave them personally othered and uniquely liminal in ways that are destructive to moral agency. Finally, I conclude with a challenge to the pronatalist master narratives by suggesting the possibility of counter narratives to the voluntarily childless woman's liminality that might serve as the ground of moral and political solidarity among differently situated women, regardless of their motherhood status.  相似文献   

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A comparative study was performed of the absorption, the plasma level at equilibrium, and the urinary excretion of digoxin using two types of Lanoxin tablets, those produced before and after the 1972 alteration of the tablet manufacture.After a single dose the absorption rate of the new tablets was about twice as great as the old, both in young subjects and in the elderly patients. There were no significant differences in the plasma levels of digoxin for the two tablets 15 hours after the last administration in patients on an equal maintenance dose. The urinary excretion of digoxin increased about 40% when the “old” Lanoxin was replaced by the “new.” In elderly patients a daily dose of 0·125 mg twice daily of the new tablets should be sufficient to reach the therapeutic range. Young people need a higher dosage. If the kidney function is reduced by as much as 50% the dose should be reduced.  相似文献   

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