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1.
C. Blut J. Wilbrandt D. Fels E.I. Girgel K. Lunau 《Entomologia Experimentalis et Applicata》2012,143(3):231-244
Many species of lepidoptera bear conspicuous circular patterns on their wings, known as eyespots, that are hypothesised to protect their bearers against predatory birds. In this study, we focus on a small but ubiquitous feature occurring naturally in lepidopteran eyespots, namely the so‐called ‘sparkle’. The ‘pupil’ in an eyespot is often highlighted by a ‘sparkle’, which is hypothesised to mimic a natural corneal total light reflection evident as a highlight, twinkle, or sparkle in the vertebrate eye. In a study exploring the presence of such sparkles, we found that 53% of lepidopteran eyespots exceeding 1 mm in diameter have a central, pinpoint‐like ‘sparkle’, 12% have a marginal, crescent‐shaped ‘sparkle’, 13% have a semi‐circular ‘sparkle’, and 22% have an intermediate semi‐circular to crescent‐shaped ‘sparkle’. In the lepidopterans’ natural resting position, the marginal ‘sparkles’ are positioned in the upper part of the eyespots’‘pupil’ and thus may create the illusion of a spherical eyeball. The ‘sparkles’ in lepidopteran eyespots do not only appear white to humans, but also reflect ultraviolet light. White and UV‐reflecting ‘sparkles’ also appear ‘white’ for UV‐sensitive viewers such as birds, and thus may effectively mimic the natural highlight in vertebrate eyes as an area of total light reflection. In field experiments using lepidopteran dummies baited with a mealworm, we show that the ‘sparkle’ is one of several components of eyespots eliciting a deterrent effect and that eyespots with a ‘sparkle’ in a natural position have a stronger deterrent effect than those with a ‘sparkle’ in an unnatural position. These findings support the eye mimicry hypothesis that better vertebrate eye mimicry improves the deterrent effect of eyespots. 相似文献
2.
Paolo Heywood 《The journal of the Royal Anthropological Institute》2015,21(4):855-871
This article addresses a classic ethnographic problem in the study of Italy: how is it that people can subscribe simultaneously to seemingly contradictory ideologies, such as Catholicism and Communism? It does so by describing examples from Italy's ‘showcase city’ of the left, ‘Red Bologna’, in which to be ‘red’ is ubiquitous but each person's ‘red’ is a different thing: being ‘red’ (differently) is the idiom in which real political distinctions are expressed over issues like religion or immigration. In parallel, I discuss the relationship between the ‘field’ as a location and the ‘field’ as a conceptual topic. My account replicates internal ethnographic differences at the analytical level by highlighting the differences between being left‐wing in Bologna and its meaning as a concept in anthropology. Hence the ‘equivocal location’: a field‐site that is productively different, from what an inexperienced ethnographer expected from it, from conceptual discussions in anthropology, and from itself. 相似文献
3.
Companion plants grown as ‘trap crops’ or ‘intercrops’ can be used to reduce insect infestations in field crops. The ways in which such reductions are achieved are being described currently using either a chemical approach, based on the ‘push‐pull strategy’, or a biological approach, based on the ‘appropriate/inappropriate landing theory’. The chemical approach suggests that insect numbers are reduced by chemicals from the intercrop ‘repelling’ insects from the main crop, and by chemicals from the trap‐crop ‘attracting’ insects away from the main crop. This approach is based on the assumptions that (1) plants release detectable amounts of volatile chemicals, and (2) insects ‘respond’ while still some distance away from the emitting plant. We discuss whether the above assumptions can be justified using the ‘appropriate/inappropriate landing theory’. Our tenet is that specialist insects respond only to the volatile chemicals released by their host plants and that these are released in such small quantities that, even with a heightened response to such chemicals, specialist insects can only detect them when a few metres from the emitting plant. We can find no robust evidence in the literature that plant chemicals ‘attract’ insects from more than 5 m and believe that ‘trap crops’ function simply as ‘interception barriers’. We can also find no evidence that insects are ‘repelled’ from landing on non‐host plants. Instead, we believe that ‘intercrops’ disrupt host‐plant finding by providing insects with a choice of host (appropriate) and non‐host (inappropriate) plant leaves on which to land, as our research has shown that, for intercropping to be effective, insects must land on the non‐host plants. Work is needed to determine whether non‐host plants are repellent (chemical approach) or ‘non‐stimulating’ (biological approach) to insects. 相似文献
4.
Matiss Castorena Julieta A Rosell Mark E Olson 《Botanical journal of the Linnean Society. Linnean Society of London》2015,179(3):361-373
Discrete plant habit categories such as ‘tree’, ‘shrub’, and ‘liana’ belie continuous variation in nature. To study the evolution of this continuous variation, we gathered data on stem length, diameter and tissue mechanical stiffness across a highly morphologically diverse highland xerophytic scrub on a lava flow in central Mexico. With stem allometric and mechanical data from 1216 segments from 50 species, we examined relationships between stem length–diameter proportions and tissue mechanical stiffness using linear mixed‐effects models. Rather than a series of discrete clouds in stem length–diameter–tissue stiffness space, corresponding to traditional habit categories, the plants of this xerophytic scrub formed a single continuous one. Within this cloud, self‐supporting plants had stems that became predictably longer and tissues that became stiffer for a given diameter increase, and there was no paucity of intermediates between trees and shrubs (‘trubs’). Non self‐supporting plants had a steeper stem length–diameter slope and their tissues did not increase in stiffness with stem size. The area between self‐ and non self‐supporting plants was sparsely occupied as stem size increased. We predict that this ‘empty’ space between lianas and trees is developmentally accessible but of low fitness, meaning that there should be few ‘trianas’ in nature. © 2015 The Linnean Society of London, Botanical Journal of the Linnean Society, 2015, 179 , 361–373. 相似文献
5.
Dan Rosengren Stefan Permanto Anders Burman 《The journal of the Royal Anthropological Institute》2023,29(4):840-858
Based on the observation that the Anthropocene narrative signifies a departure from the Cartesian nature/culture division dominant within modernist science, this article explores notions of personhood and agency among Amerindian peoples in the Amazon, the Andes, and Mesoamerica in comparison to the corresponding notions in modernist discourses. We discuss the differences in conceptualizations in relation to diverging understandings of climate change and the Anthropocene, focusing on perspectives on agentivity both within our respective ethnographical fields and in modernist social sciences. This leads us to stress the significance of new materialists’ disregard for intentionality in relation to agency and the consequences this neglect has for understanding animist perspectives. We examine the different views in relation to their effects on morality and to perceived forms of accountability. In accordance, the modernist ‘global we’, prominent in the Anthropocene debate stressing the role of humanity as a species, is contrasted with what we call a ‘universal we’, which includes both human and other-than-human persons, in conformance with Amerindian animist perspectives on the world. This approach to the issue does not only mean that we challenge the obvious iniquity in blaming all of humanity for climate change but also that we point to the coloniality of reality implicit in the Anthropocene narrative. 相似文献
6.
David Trigger 《The Australian journal of anthropology》1999,10(2):163-176
Contesting discourses about natural resource development present a rich arena for ethnographic investigation. This paper focuses on interviews with environmental activists and forest industry defenders to document a struggle over the meaning of land, work and nature in the southwest of Western Australia. While Green activists condemn what they regard as crimes against nature, this moral challenge to rural communities from urban-based environmentalism is inverted by those working in the industry, such that local cultural practices are celebrated in the face of what is seen as emotional and non-scientific rhetoric. Conflicts about resource development are thus driven in significant respects by identity politics. The paper argues for the importance of cultural analysis, focused particularly on concepts of identity and ‘place’, in the study of contesting moral claims about what should be done with ‘the environment’. 相似文献
7.
Christine Overall 《Bioethics》2015,29(5):353-361
A serious moral weakness of reproductive ‘surrogacy’ is that it can be harmful to the children who are created. This article presents a proposal for mitigating this weakness. Currently, the practice of commercial ‘surrogacy’ operates only in the interests of the adults involved (the gestator and the commissioning individuals who employ her), not in the interests of the child who is created. Whether ‘surrogacy’ is seen as the purchase of a baby, the purchase of parental rights, or the purchase of reproductive labor, all three views share the same significant flaws. They endorse the transfer, for a fee, of the infant from the woman who gestated it to those who commissioned it, but without justifying such a transfer; they fail to demonstrate that the commissioners have any entitlement to the infant, or, for that matter, suitability to be the infant's parents; and they fail to take any notice of the infant's needs, interests, and wellbeing. A mere genetic connection is not enough to establish that the commissioners are entitled to receive the baby or that they are competent to raise it. Their good intentions, however caring, are not enough. Therefore, just as in the practice of adoption, there should be a formal institutionalized system for screening and licensing the prospective social parents, which would make the infant's needs, interests, and wellbeing paramount. I reply to several potential objections to this proposal, including the objection that genetic parents who raise their own child are not screened and licensed. 相似文献
8.
SAMIA HURST 《Bioethics》2010,24(8):439-444
Uncertainty as to how we should articulate empirical data and normative reasoning seems to underlie most difficulties regarding the ‘empirical turn’ in bioethics. This article examines three different ways in which we could understand ‘empirical turn’. Using real facts in normative reasoning is trivial and would not represent a ‘turn’. Becoming an empirical discipline through a shift to the social and neurosciences would be a turn away from normative thinking, which we should not take. Conducting empirical research to inform normative reasoning is the usual meaning given to the term ‘empirical turn’. In this sense, however, the turn is incomplete. Bioethics has imported methodological tools from empirical disciplines, but too often it has not imported the standards to which researchers in these disciplines are held. Integrating empirical and normative approaches also represents true added difficulties. Addressing these issues from the standpoint of debates on the fact‐value distinction can cloud very real methodological concerns by displacing the debate to a level of abstraction where they need not be apparent. Ideally, empirical research in bioethics should meet standards for empirical and normative validity similar to those used in the source disciplines for these methods, and articulate these aspects clearly and appropriately. More modestly, criteria to ensure that none of these standards are completely left aside would improve the quality of empirical bioethics research and partly clear the air of critiques addressing its theoretical justification, when its rigour in the particularly difficult context of interdisciplinarity is what should be at stake. 相似文献
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Although the anthropological literature on ritual is extensive, little theoretical attention has been paid to recent attempts to (re)create rituals among mainstream groups in post-industrial, secularised societies. The authors address this issue by examiuning the annual Fire Event, which is constructed as a ritual climax to the Maleny Folk Festival in southern Queensland, Australia. Using the work of Victor Turner and John MacAloon as a point of departure, we argue that at best such celebrations constitute a neo-liminal framework within which participants can achieve a consensus of belief and action. By showing that some Fire Events have been more successful ‘rituals’ than others, we also highlight the factors which tend to impede participation and ‘con-subjectivity’ in such settings. In the process we identify some of the cultural divisions at Maleny, such as those between artists and ‘folk’, feral hippies and ‘hoons’, Aboriginals and Anglos, and begin to reflect on how these may relate to more general patterns of interaction in Australian society at large. 相似文献
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12.
Site‐specific conjugation of the quencher on peptide's N‐terminal for the synthesis of a targeted non‐spreading activatable optical probe
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Bryan Simard Gleb G. Mironov Boguslaw Tomanek Frank C. J. M. van Veggel Abedelnasser Abulrob 《Journal of peptide science》2016,22(6):415-420
Optical imaging offers high sensitivity and portability at low cost. The design of ‘smart’ or ‘activatable’ probes can decrease the background noise and increase the specificity of the signal. By conjugating a fluorescent dye and a compatible quencher on each side of an enzyme's substrate, the signal remains in its ‘off ’ state until it reaches the area where a specific enzyme is expressed. However, the signal can leak from that area unless the dye is attached to a molecule able to bind to a specific target also presented in that area. The aim of this study was to (i) specifically conjugate the quencher on the α‐amino group of the peptide's N‐terminus, (ii) conjugate the dye on the ε‐amino group of a lysine in C‐terminus, and (iii) conjugate the carboxyl group of the peptide's C‐terminus to an amino group present on an antibody, using carbodiimide chemistry. The use of protecting groups, such as Boc or Fmoc, to allow site‐specific conjugation, presents several drawbacks including ‘on beads labeling’, additional steps required for deprotection and removal from the resin, decreased yield, and dye degradation. A method of preferential labeling of α‐amino N‐terminal group in slightly acidic solution, proposed by Selo et al. (1996) has partially solved the problem. The present study reports improvements of the method allowing to (i) avoid the homo‐bilabeling, (ii) increase the yield of the N‐terminal labeling by two folds, and (iii) decrease the cost by 44‐fold. Copyright © 2016 European Peptide Society and John Wiley & Sons, Ltd. 相似文献
13.
Dundi Mitchell 《The Australian journal of anthropology》1996,7(1):258-274
In the last decade there has been much interest in the concepts of ‘racism’ and ‘essentialism’ and the ways in which these notions have been appropriated by Aboriginal people to demarcate a specifically Aboriginal space (Cowlishaw 1986; Lattas 1993; Langton 1981; Morris 1988; Muecke 1992). Central to these concerns is the issue of black/white relations and the specificities of racial oppression. Following these concerns in this article I explore the nexus between the metaphorical dismemberment of self and the corporeal dismemberment of sickness which is reflected in the high mortality rates and disease patterns of Aboriginal people. I extend Fanon's concept that racism has the power to alienate ‘a man of colour’ from his own self-image to argue that it more than metaphorically breaks the human body (Fanon 1991). I provide a window into a much neglected area of research: how notions of illness and social relatedness are constructed in particular socio-historical circumstances. I explore the meanings of illness as expressed at the level of community and as a form of embodiment associated with unequal colonial relations. I focus on indigenous exegeses which articulate Aboriginal women's experience of illness and their sense of identity. I draw on the work of Leder (1990) to foreground a phenomenological view where selfhood is continually confronted by circumstances that make present the ‘body’ as a ‘sharp and searing presence threatening the self’. I also apply Sansom's (1982) model of illness and the significance of carers in an Aboriginal community to demonstrate a world-view of personhood that is diffused with other persons and things rather than a world-view that entails a highly individuated and bounded self. In this world-view adequate healing requires a reconstitution of social relations and a re-ordering of the racialised status quo. 相似文献
14.
John P. Taylor 《The Australian journal of anthropology》2008,19(2):165-178
In the northern Vanuatu town of Luganville a small group of men have responded to social and legal changes engendered by women's rights activists by forming a male support group called ‘Violence Against Men’. Members of this ‘backlash’ movement argue that the insidious promotion of Western‐style ‘women's rights’ is leading to discrimination against men in divorce proceedings, child custody battles, and in domestic violence and rape cases. They directly oppose recent and ongoing legal changes aimed at protecting women from domestic violence, such as Domestic Violence Protection Court Orders, and the repeatedly tabled (but long‐delayed) ‘Family Protection Bill’. Such interventions, they argue, undermine Vanuatu's ‘natural’kastom and Christian patriarchal gender order and, in doing so, pose a serious threat to the socio‐economic productivity of the nation‐state. For other men, however, rather than opposing women's rights activism, such challenges have raised questions about how men might successfully negotiate their identities in ways that are sensitive to contemporary issues of gender equality without undermining existing paradigms. Thus, this paper addresses the value accorded to universalism and relativism in gender activism in Vanuatu, and especially in terms of the linked discourses of kastom, church and modernity. It therefore explores gender relations in terms of the contemporary entanglement of indigenous and exogenous epistemologies, and in doing so argues that the contextual analysis of ‘rights’ should consider the specific historical, political and socio‐cultural circumstances in which they are put to use. 相似文献
15.
Catherine Palmer 《The Australian journal of anthropology》2002,13(3):323-336
This article details the particular commodification of those high‐risk, highadrenalin activities known collectively as ‘extreme sports’. A variety of commercial operators now offer relative sporting neophytes the chance to take part in mountaineering, snow boarding or canyonning adventures that are billed as being ‘high thrill, low risk’. It is the way in which the risk and danger involved in these activities is discursively managed that is of particular interest for this article. The argument developed is that in selling extremity through a range of primarily tourist‐oriented commercial avenues, the very real prospect of death and injury has been stripped from the activity itself. To elaborate this position, this article draws on several sporting disasters, including the much publicised, ill‐fated ascent of Mount Everest in 1996, and the Interlaken canyonning disaster of 1999, as well as the burgeoning literary and media genre—the made‐for‐Hollywood ‘adventure saga’. 相似文献
16.
In the hope of future treatments to prevent or slow down the disease, there is a strong movement towards an ever‐earlier detection of Alzheimer’s disease (AD). In conjunction with scientific developments, this has prompted a reconceptualization of AD, as a slowly progressive pathological process with a long asymptomatic phase. New concepts such as ‘preclinical’ and ‘prodromal’ AD have been introduced, raising a number of conceptual and ethical questions. We evaluate whether these new concepts are theoretically defensible, in light of theories of health and disease, and whether they should be understood as disease or as an at‐risk state. We introduce a pragmatic view on disease concepts and argue that an evaluation of the reconceptualization of AD should also take its aims and effects into account, and assess their ethical acceptability. The reconceptualization of AD is useful to coordinate research into preventive strategies, and may potentially benefit future patients. However, in the short term, early detection and labelling of ‘preclinical AD’ can potentially harm people. Since there is no treatment available and the predictive value is unclear, it may only create a group of ‘patients‐in‐waiting’ who may suffer from anxiety, uncertainty and stigmatization, but will never actually develop dementia. We conclude that only if the promise of preventive medication materializes, will the reconceptualization of AD turn out unequivocally to be for the better. Otherwise, the reconceptualization may do more harm than good. 相似文献
17.
Lee 《Journal of evolutionary biology》1999,12(4):724-734
Many have argued strongly that incorporation of evolutionary theory into systematics is dangerously circular, while others have maintained that such an integrated approach increases the accuracy of phylogenetic inference. Here, it is demonstrated that such blanket statements regarding exclusion or inclusion of evolutionary principles in systematics fail to distinguish between two very different types of principles. ‘Phylogeny-neutral’ evolutionary principles are those inferred without any recourse to specific phylogenetic hypotheses (e.g. via developmental genetics, biomechanics). In contrast, ‘phylogeny-dependent’ principles are those which can only be inferred on the basis of specific phylogenetic hypotheses (e.g. character associations detected via ‘comparative methods’). Inclusion of phylogeny-neutral principles in systematic studies as a priori assumptions can be justified, since these principles have (often strong) external empirical support from other spheres of investigation. However, inclusion of phylogeny-dependent principles in systematic studies is circular, since such principles have no external empirical support but are themselves derived from systematic studies. Advocating inclusion or exclusion of all (or as many as possible) evolutionary principles from phylogenetic analysis is therefore misguided. Rather, phylogeny-neutral principles are independently supported and can be included, while phylogeny-dependent principles are unjustified assumptions and should be excluded to avoid circularity. However, integration of complex phylogeny-neutral principles in systematics can create operational problems, even though there are no methodological reasons against their inclusion. 相似文献
18.
Martin S. Westwell Mark S. Searle Dudley H. Williams 《Journal of molecular recognition : JMR》1996,9(2):88-94
The cooperativity which exists in crystal melting and many biological molecular recognition phenomena arises from extended arrays of weak interactions. We present a correlation between the melting temperature of a crystal and the intermolecular energy (which is evident only when compounds possessing several or many internal rotors are excluded). The correlation is used as the basis for a model of crystal melting which is capable of estimating the melting temperature of crystals. This model provides the basis for an understanding of the sharpness of the crystal melting transition for organic and inorganic substances. The cooperativity illustrated by the extended arrays of weak interactions, or the ‘n’ effect, is extended to analogous order/disorder transitions in biological systems, such as the ‘melting’ of DNA and RNA duplexes, providing insights into the physical properties of these structures. 相似文献
19.
The purpose of this note is to provide an alternative to the interpretation of multidimensionality in parasite‐induced phenotypic alterations as a set of effectively‐independent traits produced by adaptive evolution. We propose here that infection with so‐called ‘manipulative parasites’ typically results in an ‘infection syndrome’, characterized by several distinctive symptoms corresponding to the alteration of particular phenotypic traits in infected hosts. Based on the available physiological evidence, we argue that symptoms might actually be the consequence of the dysregulation of some key neuromodulator, arising as a byproduct of the subversion of the host's immune system by the parasite. In that respect, it might be inadequate, from a functional point of view, to separate phenotypic effects that appear to increase trophic transmission from those that do not. We suggest that future research should test the validity of the ‘infection syndrome’ hypothesis through focusing on the mechanisms involved in multidimensionality at the intraspecific level, and through looking for the existence of non‐random associations between symptoms at the interspecific level, across host‐parasite associations. 相似文献
20.
Ye Rin Lee Jae Bok Yoon Jundae Lee 《Molecular breeding : new strategies in plant improvement》2016,36(5):61
Capsicum baccatum L., one of five domesticated species of Capsicum, is a valuable species in chili pepper breeding. In particular, it is a source of disease resistance against anthracnose and powdery mildew. Genetic maps and molecular markers are important to improve the efficiency of crop breeding programs. Recently, using genetic maps several researchers have identified quantitative trait loci (QTLs) for important horticultural traits and have cloned genes of interest. In this study, we constructed a genetic map of C. baccatum in an intraspecific population from a cross between ‘Golden-aji’ and ‘PI594137.’ A total of 395 high-resolution melting markers were developed based on single-nucleotide polymorphisms identified by comparing genome sequences generated through next-generation resequencing of the parents, ‘Golden-aji’ and ‘PI594137.’ The genetic linkage map contained 12 linkage groups, covered a total distance of 1056.2 cM, and had an average distance of 2.67 cM between markers. In addition, the final map was compared to the reference physical map of C. annuum ‘CM334.’ Interestingly, two major reciprocal translocations between chromosomes 3 and 5 and between chromosomes 3 and 9 were found, suggesting that these translocations might act as a genetic barrier between C. annuum and C. baccatum. Translocations between chromosomes 1 and 8 were also observed, as were previously reported in C. chinense, C. frutescens, and wild C. annuum. The synteny of other chromosomes was maintained, on the whole, except for several small inversions. The information on this genetic map will be helpful to analyze QTLs for important traits such as anthracnose resistance in C. baccatum and to study the causes of genetic barriers between C. annuum and C. baccatum. 相似文献