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1.
This paper examines a Martinican theatrical troupe's development of a play about Haitian peasant life for an annual cultural festival. It examines why such a play was chosen for a festival which is dedicated to showcasing and celebrating Martinican culture. It also charts and analyses differences between the theatrical elite (playwright, director and experienced actors) and ‘debutants’ (new members of the company) over the significance of Haiti in Martinique and the representation of Haitian peasants in rehearsals leading up to the opening night. I argue that although the ‘quest for the authentic’ may be common to all theatre participants, the content and objectives of such a quest differ depending on an individual's theatrical experience and relationship to specific cultural ideologies. For those with a significant political and/or emotional investment in the cultural ideology of Negritude, Haiti's successful revolution against France in 1804 signifies a heroic past (of an independent black republic) that Martinique lacks. For those without such investments, Haiti is viewed more critically as a poverty stricken and illiterate society. For this latter group, authenticity, rather than being achieved through a narrative of displaced history (based upon an assumption of cultural identity), can be attained through the act of acting (based upon an assumption of individual identity).  相似文献   

2.
Sinorhizobium meliloti DctB is a typical transmembrane sensory histidine kinase, which senses C4‐dicarboxylic acids (DCA) and regulates the expression of DctA, the DCA transporter. We previously reported the crystal structures of its periplasmic sensory domain (DctBp) in apo and succinate‐bound states, and these structures showed dramatic conformational changes at dimeric level. Here we show a ligand‐induced dimeric switch in solution and a strong correlation between DctBp's dimerization states and the in vivo activities of DctB. Using site‐directed mutagenesis, we identify important determinants for signal perception and transduction. Specifically, we show that the ligand‐binding pocket is essential for DCA‐induced ‘on’ activity of DctB. Mutations at different sections of DctBp's dimerization interface can lock full‐length DctB at either ‘on’ or ‘off’ state, independent of ligand binding. Taken together, these results suggest that DctBp's signal perception and transduction occur through a ‘ligand‐induced dimeric switch’, in which the changes in the dimeric conformations upon ligand binding are responsible for the signal transduction in DctB.  相似文献   

3.
Sustained divisions of protoplast-derived cells obtained from cell suspension cultures of Rosa‘Paul's Scarlet’ leading to colony and callus formation was achieved. The rather low plating efficiencies observed for agar-plated protoplasts were partly due to early arrests in further development of dividing protoplast-derived cells and cell clusters. Successful cultivation of dividing protoplast-derived cells was particularly dependent upon frequent subculturing of the precultures and on an efficient procedure for viable protoplast isolation. Colony formation was largely independent of medium composition.  相似文献   

4.
It is nearly two decades now since the publication of Godfrey Tangwa's article, ‘Bioethics: African Perspective’, without a critical review. His article is important because sequel to its publication in Bioethics, the idea of ‘African bioethics’ started gaining some attention in the international bioethics literature. This paper breaks this relative silence by critically examining Tangwa's claim on the existence of African bioethics. Employing conceptual and critical methods, this paper argues that Tangwa's account of African bioethics has some conceptual, methodic and substantive difficulties, which altogether do not justify the idea of African bioethics, at least for now. Contra Tangwa, this article establishes that while African bioethics remains a future possibility, it is more cogent that current efforts in the name of ‘African bioethics’ be primarily re‐intensified towards ‘Healthcare ethics in Africa’.  相似文献   

5.
Haldane's rule is one of the ‘two rules of speciation’. It states that if one sex is ‘absent, rare or sterile’ in a hybrid population, then that sex will be heterogametic. Since Haldane first made this observation, 100 years have passed and still questions arise over how many independent examples exist and what the underlying causes of Haldane's rule are. This review aims to examine research that has occurred over the last century. It seeks to do so by discussing possible causes of Haldane's rule, as well as gaps in the research of these causes that could be readily addressed today. After 100 years of research, it can be concluded that Haldane's rule is a complicated one, and much current knowledge has been accrued by studying the model organisms of speciation. This has led to the primacy of dominance theory and faster-male theory as explanations for Haldane's rule. However, some of the most interesting findings of the 21st century with regard to Haldane's rule have involved investigating a wider range of taxa emphasizing the need to continue using comparative methods, including ever more taxa as new cases are discovered.  相似文献   

6.
Magnus Course 《Ethnos》2013,78(1):77-101
The amulpüllün biographical oratory which takes place at Mapuche funerals in southern Chile is said to ‘complete’ the person. Such a perspective challenges the assumption that mortuary practices necessarily constitute a form of analysis, a division of the component parts of the social person. In this paper I explore what it is about the Mapuche person which needs to be ‘completed,’ and how funeral oratory achieves this goal. Utilizing Bakhtin's concepts of consummation and transgredience, and Ricoeur's concepts of emplotment and narrative identity, I suggest that it is only from the position of outsidedness that the necessary totalization of the deceased's person can occur. These processes of synthesis and totalization cast light upon an apparent contradiction between the importance which Amerindians place upon biography as an oral form, and theoretical approaches which stress the instability and divisibility of an Amerindian personhood predicated upon the incorporation of the other. Rather than viewing the totalization which occurs in biography as a critique of such an approach, I see it as a solution to the ontological problem which such an approach describes.  相似文献   

7.
In 1936, Erwin Bünning suggested that photoperiodic time measurement was a function of the circadian system. Colin Pittendrigh became an ardent supporter of Bünning's hypothesis, drawing parallels between photoperiodism and his own group's investigations of adult eclosion rhythmicity in the fruit fly Drosophila pseudoobscura. They developed several more modern versions of Bünning's general hypothesis based on the entrainment of circadian oscillations to the light cycle, including ‘external coincidence’, which is a derivation of Bünning's original model, and ‘internal coincidence’, which relied upon seasonal changes in the mutual phase relationship of oscillators within a multi‐oscillator circadian system. This review considers the experimental evidence for the central role of the circadian system in photoperiodic timing and, in some species, for both external and internal coincidence. Pittendrigh, however, pursued the idea of internal coincidence further with his analysis of the pacemaker–slave organization of eclosion rhythmicity in D. pseudoobscura and proposed a similar theoretical model for photoperiodism comprising a group of slave oscillators driven by a light‐sensitive pacemaker. In this model, the phase relationships of the slaves to the pacemaker were affected by (i) the relative periods of the pacemaker and slave(s); (ii) the strength(s) of the coupling between the two; and (iii) the dampening coefficients of the various slaves. Manipulation of these variables showed that the slaves adopted different internal phase relationships (both to each other and to the pacemaker) under the influence of changes in daily photophase, the period of the Zeitgeber and phase shifts of the entraining light cycle.  相似文献   

8.
We investigated the connection between plant species diversity and climate by using a process‐based, generic plant model. Different ‘species' were simulated by different values for certain growth‐related model parameters. Subsequently, a wide range of values were tested in the framework of a ‘Monte Carlo' simulation for success; that is, the capability of each plant with these parameter combinations to reproduce itself during its lifetime. The range of successful parameter combinations approximated species diversity. This method was applied to a global grid, using daily atmospheric forcing from a climate model simulation. The computed distribution of plant ‘species' diversity compares very well with the observed, global‐scale distribution of species diversity, reproducing the majority of ‘hot spot' areas of biodiversity. A sensitivity analysis revealed that the predicted pattern is very robust against changes of fixed model parameters. Analysis of the climatic forcing and of two additional sensitivity simulations demonstrated that the crucial factor leading to this distribution of diversity is the early stage of a plant's life when water availability is highly coupled to the variability in precipitation because in this stage root‐zone storage of water is small. We used cluster analysis in order to extract common sets of species parameters, mean plant properties and biogeographic regions (biomes) from the model output. The successful ‘species' cannot be grouped into typical parameter combinations, which define the plant's functioning. However, the mean simulated plant properties, such as lifetime and growth, can be grouped into a few characteristic plant ‘prototypes', ranging from short‐lived, fast growing plants, similar to grasses, to long‐lived, slow growing plants, similar to trees. The classification of regions with respect to similar combinations of successful ‘species' yields a distribution of biomes similar to the observed distribution. Each biome has typical levels of climatic constraints, expressed for instance by the number of ‘rainy days' and ‘warm days'. The less the number of days favourable for growth, the greater the level of constraints and the less the ‘species' diversity. These results suggest that climate as a fundamental constraint can explain much of the global scale, observed distribution of plant species diversity.  相似文献   

9.
This paper examines claims made about the role of ‘expert knowledge’ in analysing the language of individuals seeking asylum in the UK. I treat policy as a type of power and seek to understand how this policy uses the language of science to further the British government's stated interest to provide ‘secure borders’ and a ‘safe haven’ for refugees. I look at how the Home Office defines, shapes and implements the policy, and at how the policy has influenced judicial decisions. In short I unmask UKBA's claim that it relies upon expert, scientific knowledge to assess asylum claims.  相似文献   

10.
Reliance upon unpaid and committed family labour is said to make many ethnic businesses competitive. However, most analysts' references to this labour have not taken into account the nature of family members' and, in particular, children's work roles or the ways in which their labour is elicited and maintained. Here, the nature of children's labour participation in ethnic businesses is investigated in the case of families running Chinese take‐away businesses in Britain. This article focuses on how children in these families understand their often double‐edged experiences of ‘helping out’, as part of a ‘family work contract’, and on the ways in which families negotiate children's labour over time. Given these families' experiences of migration and ethnic minority status, I argue that Chinese children's work in take‐away businesses must be examined in relation to the intersections of family obligations and relationships, livelihood strategies and pressures, and issues of cultural identity.  相似文献   

11.
We examined the occurrence of six species of meadow birds (four wader species and two songbird species) in relation to the distance to the nest location of an avian predator (three species). We related our findings to the degree of openness of the landscape in which this avian predator nest was located. The degree of openness varied from very open to very closed, depending on the number of view‐obstructing landscape elements in the landscape (none or very few in open ones, but completely covered with forest or built‐up area in very closed landscapes). We used a dataset containing nesting locations of meadow birds and predators in the province of Gelderland, the Netherlands, allowing us to perform the analysis on three grid cell sizes (100×100 m, 250×250 m and 500×500 m). Our results show that, for each grid cell size, all meadow bird species showed highest nesting densities in open landscapes. Lowered densities were found around occupied nests of avian predators, irrespective whether the predator's nest was situated in an open or closed landscape. The preference of meadow birds for open landscapes away from predator's nests suggests that a large visibility, that allows them to scan for predators to be able to chase them away in time, is an important habitat requirement for meadow birds to select a nest site. It also suggests that openness of the landscape, independent from the presence of occupied predator's nests, is a factor in selecting a nest site. In contrast, for two out of three species of avian predator, we found that they chose more closed landscapes to nest because these species nest in landscape elements like wood lots and lone trees which make the landscape more closed by definition. For the third avian predator species, the grid cell size was probably too small to find a consistent result, as that species has territories larger than even the largest grid cell size we used.  相似文献   

12.
Katharine Tyler 《Ethnos》2013,78(3):391-412
This article explores ethnographically the ‘village’ as a stage for the enactment and reproduction of a racialised set of white middle-class social and moral values. To do this I draw upon interview material with middle-class whites who live in a suburban ‘village’ on the border of rural Leicestershire and urban Leicester in England. I explore the way in which my co-conversationalists reflexively and imaginatively defend their area's ‘village’ identity through a discourse that ‘others’ its wealthy Asian residents. Although these raced others have achieved economic parity with the more affluent wealthy white middle-class residents, they are imagined to lack the ‘proper’ middle-class values of respectability and decorum, which are associated with the traditional white rhythms of English village life.  相似文献   

13.
Among horizontally acquired symbioses, the mechanisms underlying microbial strain- and species-level specificity remain poorly understood. Here, confocal-microscopy analyses and genetic manipulation of the squid–vibrio association revealed quantitative differences in a symbiont's capacity to interact with the host during initial engagement. Specifically, dominant strains of Vibrio fischeri, ‘D-type’, previously named for their dominant, single-strain colonization of the squid's bioluminescent organ, were compared with ‘S-type’, or ‘sharing’, strains, which can co-colonize the organ. These D-type strains typically: (i) formed aggregations of 100s–1000s of cells on the light-organ surface, up to 3 orders of magnitude larger than those of S-type strains; (ii) showed dominance in co-aggregation experiments, independent of inoculum size or strain proportion; (iii) perturbed larger areas of the organ's ciliated surface; and, (iv) appeared at the pore of the organ approximately 4×s more quickly than S-type strains. At least in part, genes responsible for biofilm synthesis control the hyperaggregation phenotype of a D-type strain. Other marine vibrios produced relatively small aggregations, while an array of marine Gram-positive and -negative species outside of the Vibrionaceae did not attach to the organ's surface. These studies provide insight into the impact of strain variation on early events leading to establishment of an environmentally acquired symbiosis.  相似文献   

14.
A new regimen for the management of diabetic crises in children using small doses of intramuscular insulin and generous amounts of intravenous fluids has been devised. Insulin dosage was calculated from the patient''s weight and was independent of the degree of hyperglycaemia. Minimum demands were made upon the laboratory.  相似文献   

15.
This article examines the significance of pockets for controlling money in Highland Papua New Guinea. Contextualizing elaborate ‘systems’ for compartmentalizing monies in separate pockets, I draw upon the connection Highlanders make between transaction and skin. Pockets, I argue, offer opportunities to hide one's wealth reserves while gifting, keeping intentions opaque and leaving interlocutors guessing at the meaning of donors' speech, and forcing recipients to perceive their gift as ample. The article suggests that expectations are deliberately conventionalized in order to be exceeded, drawing parallels with Roy Wagner's notion of obviation. After characterizing Gorokan pockets and their gifting ‘logic’, I analyse how pocket‐users are themselves conventionalized as forthright or selfish in local discourse, based upon the pockets they display and where their clothes come from. Giving people clothing that includes pockets is therefore a way to regain control over their capacity to reveal wealth from their pockets.  相似文献   

16.
In writing on ‘John Rex's Main Mistake’, Michael Banton reveals more about Banton than he does about Rex. I use Banton's discussion of the differences between his own and John Rex's ‘mistakes’ to explore why, in my view, race continues to have analytical purchase in a purportedly ‘post-racial’ age  相似文献   

17.
The lipophosphoglycan-like (LPG-like) molecules of E. histolytica virulent strains are clearly distinct from those of the avirulent E. histolytica and E. dispar strains. Abundant ‘LPG’ levels are apparently limited to virulent strains, while lipophosphopeptidoglycans (‘LPPG's) are common to both virulent and avirulent strains of E. histolytica and E. dispar. It is therefore conceivable that ‘LPPG’ performs a function that is essential to survival within the host, while the ‘LPG’ performs a more specific function related to virulence.  相似文献   

18.
Neil C. Manson 《Bioethics》2019,33(5):540-549
The biobank consent debate is one with deeply held convictions on both the ‘broad’ and ‘specific’ side with little sign of resolution. Recently, Thomas Ploug and Soren Holm have developed an alternative to both specific and broad consent: a meta‐consent framework. The aim here is to consider whether meta‐consent provides a ‘solution’ to the biobank consent debate. We clarify what ‘meta‐consent’ actually is (arguing that the label is a misnomer and ‘consent à la carte’ is more accurate). We identify problems with Ploug and Holm's arguments, and some challenges for meta‐consent. We focus on whether there is any ethical obligation to provide consent à la carte. There may seem to be so, especially if we draw upon an unclear appeal to the ethical significance of ‘respect for autonomy’. Similarly, there might seem to be an intuitive inference from the fact that ethically legitimate research requires informed consent to the conclusion that it thereby requires consent à la carte. It is shown that this line of inference is mistaken.  相似文献   

19.
And he gave it for his opinion, that whoever could make two ears of corn or two blades of grass to grow upon a spot of ground where only one grew before, would deserve better of mankind, and do more essential service to his country than the whole race of politicians put together. {Jonathan Swift, ‘Gulliver's Travels’, Voyage to Brobdingnag, Ch. 7.)  相似文献   

20.
We investigated the electric organ discharge (EOD) activity of the mormyrid fish Brienomyrus niger during social encounters. The fish were contained in porous ceramic shelters and tested alone and in pairs in an experimental tank designed to restrict communication to the electrosensory modality. We moved one fish toward and away from a stationary conspecific, beginning at a distance known to be outside the range of communication (250 cm). Baseline EOD activity was recorded prior to interaction and categorized as ‘variable’, ‘regular’, and ‘scallop’. When moved closer together, the fish modulated this baseline activity in four ways: (1) At 100–130 cm apart, the stationary fish emitted a maximum of sudden EOD rate increases which defined the outer limit of its communication range. (The associated Electric Field Gradient was 1 μV/cm). (2) Long EOD cessations, which we called social silence, lasted from 5–130 s and occurred most frequently when the fish were 36 to 55 cm apart (EFG: 100 μV/cm). The duration of social silence was negatively correlated (r = ? 0.862) with the responding fish's size, and was independent of the partner's sex and size. Fish whose EOD baseline pattern was ‘scallop’ were least likely to fall electrically silent, and those that were categorized as ‘regular’ or ‘variable’ were most likely to cease discharging. (3) Within electrolocation range, fish ‘regularized’ their EOD activity while the partner was ‘silent’ (EFG: 1 mV/cm). (4) Following long EOD cessations the fish resumed discharging with characteristic EOD rebound patterns. The possible ethological significance of these findings is discussed.  相似文献   

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