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2.
Discourse, and particularly discourse in dialogue form, recently has been proposed as a privileged arena for the interaction of language and society. This article examines the process by which performances of public dialogue have been structured and restructured in Gayo society, Indonesia, from 1900 to 1945. I trace changes in the formal, semantic, and contextual features of Gayo poetic duels. The integration of Gayo society into colonial and postcolonial sociopolitical frameworks is shown to have opened up performance to competing political voices, in Bakhtin's sense. Implications are drawn for current research on dialogues as models for social relations. 相似文献
6.
Phylogeographic lineages are interpreted as the product of repeated isolation in glacial refugia, leading to vicariant differentiation. Being restricted to a given geographic area could also promote adaptive divergence in response to local conditions. The role of phylogeny and climate in the evolution of the bank vole ( Myodes glareolus) was investigated here, focusing on molar tooth shape, a morphological feature related to the exploitation of food resources. A balanced role of phylogeny and climate was demonstrated. Response to environmental factors led to morphological convergence of bank voles from different lineages living in similar environments, and to within-lineage divergence in extreme environments. An important interaction of climate and phylogeny was found, suggesting that each lineage is living in a particular environment. This lineage-specific adaptation to a range of environmental conditions may have conditioned the potential of post-glacial recolonization of each lineage. Morphological covariation with environmental conditions further highlights the potential of adaptation of this species. 相似文献
9.
Market-based economic incentives are increasingly perceived as a cost-effective approach to biodiversity conservation but
empirical evidence to substantiate this claim is lacking. Using both qualitative and quantitative data analysis this paper
investigates the potential role of market incentives to increase venison production as a mechanism to resolve conflicts over
wild red deer management in the Scottish Highlands. Our analysis suggests the approach is unlikely to be effective because
investments in venison production would bring conflict with more important non-pecuniary objectives of landownership such
as ‘sporting quality’ and ‘exclusivity’. At a broader level we urge caution when considering the deployment of economic instruments
to resolve contemporary conservation conflicts where profit maximisation is not the dominant objective and/or where the target
group is extremely wealthy. 相似文献
10.
Computational models of motor control have often explained the straightness of horizontal planar reaching movements as a consequence of optimal control. Departure from rectilinearity is thus regarded as sub-optimal. Here we examine if subjects may instead select to make curved trajectories following adaptation to force fields and visuomotor rotations. Separate subjects adapted to force fields with or without visual feedback of their hand trajectory and were retested after 24 hours. Following adaptation, comparable accuracies were achieved in two ways: with visual feedback, adapted trajectories in force fields were straight whereas without it, they remained curved. The results suggest that trajectory shape is not always straight, but is also influenced by the calibration of available feedback signals for the state estimation required by the task. In a follow-up experiment, where additional subjects learned a visuomotor rotation immediately after force field, the trajectories learned in force fields (straight or curved) were transferred when directions of the perturbations were similar but not when directions were opposing. This demonstrates a strong bias by prior experience to keep using a recently acquired control policy that continues to produce successful performance inspite of differences in tasks and feedback conditions. On relearning of force fields on the second day, facilitation by intervening visuomotor rotations occurred only when required motor adjustments and calibration of feedback signals were similar in both tasks. These results suggest that both the available feedback signals and prior history of learning influence the choice and maintenance of control policy during adaptations. 相似文献
11.
A simple and inexpensive method for monitoring child mortality in association with birth registration was introduced into the Southern Highlands of Papua New Guinea. Eight thousand two hundred and one newborn infants were registered in 1988, approximately 77% of all children born in that year. The risk of death by age 2 was determined from reports given by the mother on the present status of a previously born child at the time of a recent delivery or during clinic registration of the current birth. This was 91 per 1000 for the province and corresponds to a risk of death by age 1 of 77/1000 by extrapolation using standard lifetables. This method was validated by comparison with a continuing demographic surveillance system covering 30,000 people in the western part of the province. The new birth certificate has been an incentive to increase supervised delivery rates and to generate a register that can be used to increase vaccination coverage. 相似文献
12.
This article is based on an ethnographic study I conducted in southern Morocco during 2004. I explore the historical, ideological, and cultural background behind educational specialization among Moroccan university students. I describe how French colonial educational policies and postindependence Moroccan national schooling ideologies have created a national system of double standards that: (1) privileges French-educated urban middle- and upper-class students, (2) emphasizes the Arabization of the national education system, and (3) discriminates against Arabized, largely rural students, which have exacerbated regional educational and socioeconomic inequalities. I finally contend that educational specialization in noncompetitive degrees such as Arabic language and literature, Islamic studies, geography, and general law is the result of an ideological matrix I have termed political coherence of educational incoherence. Political coherence of educational incoherence naturalizes the reliance of certain disfranchised regional groups on a traditional preschool Islamic education that is largely based on memorization and inefficient pedagogy and is unsuitable for the modern educational requirements. [Islamic education, school ethnography, Arabization, school failure, minority education] 相似文献
13.
BackgroundMalaria is a major public health problem in Bangladesh, frequently occurring as epidemics since the 1990s. Many factors affect increases in malaria cases, including changes in land use, drug resistance, malaria control programs, socioeconomic issues, and climatic factors. No study has examined the relationship between malaria epidemics and climatic factors in Bangladesh. Here, we investigate the relationship between climatic parameters [rainfall, temperature, humidity, sea surface temperature (SST), El Niño-Southern Oscillation (ENSO), the normalized difference vegetation index (NDVI)], and malaria cases over the last 20 years in the malaria endemic district of Chittagong Hill Tracts (CHT). Methods and Principal FindingsMonthly malaria case data from January 1989 to December 2008, monthly rainfall, temperature, humidity sea surface temperature in the Bay of Bengal and ENSO index at the Niño Region 3 (NIÑO3) were used. A generalized linear negative binomial regression model was developed using the number of monthly malaria cases and each of the climatic parameters. After adjusting for potential mutual confounding between climatic factors there was no evidence for any association between the number of malaria cases and temperature, rainfall and humidity. Only a low NDVI was associated with an increase in the number of malaria cases. There was no evidence of an association between malaria cases and SST in the Bay of Bengal and NIÑO3. Conclusion and SignificanceIt seems counterintuitive that a low NDVI, an indicator of low vegetation greenness, is associated with increases in malaria cases, since the primary vectors in Bangladesh, such as An. dirus, are associated with forests. This relationship can be explained by the drying up of rivers and streams creating suitable breeding sites for the vector fauna. Bangladesh has very high vector species diversity and vectors suited to these habitats may be responsible for the observed results. 相似文献
14.
Clouet, M, Barrau, C & Gar, J-L. 2000. The diurnal Afro-alpine raptor community of the Ethiopian Bale Highlands. Ostrich 71(3&4): 380-384. The diurnal raptor community of the Afro-alpine level of the Bale Highlands (i.e. 3500-4000 m a.s.l.) Ethiopia was observed during eight expeditions spread over five consecutive years. Among the 25 species recorded, nine are residents, including three which nest at lower altitudes. Small mammal hunters are the most numeraus species, including a unique assemblage of various Aquila species, among which the Golden Eogle Aquila chrysaetos is the outstanding feature. Population densities are high for Golden Eagle and Verreaux's Eagle, Aquila verreauxii, Tawny and Steppe Eagles, Aquila rapox and A. niplensis, Augur Buzzard, Buteo augur and Lanner Falcon, Falco biarmicus. This is related to the abundance of prey, mainly hyraxes, hares and rodents. For the largest species, the start of breeding coincides with the onset of the dry season (Navember). The period with the largest number of young raptors on the nest (February-March) corresponds to the peak in the prey papulation. Migrants and Palaearctic winter visitors are present at the same time and use the same faad resources as the breeders. The main factors isolating closely related species are diet for the Golden and Verreaux's Eagles and the period of habitat use for the Tawny and Steppe Eagles. 相似文献
15.
In this study we analyze the economic feasibility of commercial cultivation of Sarcopeltis skottsbergii, a red seaweed endemic in southern Chile with commercial interest as a source of carrageenan. To this end, a dynamic bioeconomic model was built that comprises three submodels, namely, a biological, a technical, and an economic one. The cultivation was by using a method where they are hung in the sea, with juveniles attached to lines. The site is located in the Bay of Ancud, in the Los Lagos Region of southern Chile. The sensitivity analysis showed that cultivation is profitable for a private investor when the price and growth of the biomass are substantially higher than the parameters established for the baseline model. The results suggest that greater technological development is required to make a culture of this type profitable and, thus, reduce the extractive pressure that is currently exerted on natural habitats. 相似文献
16.
The persistence of life requires populations to adapt at a rate commensurate with the dynamics of their environment. Successful populations that inhabit highly variable environments have evolved mechanisms to increase the likelihood of successful adaptation. We introduce a 64 × 64 matrix to quantify base-specific mutation potential, analyzing four different replicative systems, error-prone PCR, mouse antibodies, a nematode, and Drosophila. Mutational tendencies are correlated with the structural evolution of proteins. In systems under strong selective pressure, mutational biases are shown to favor the adaptive search of space, either by base mutation or by recombination. Such adaptability is discussed within the context of the genetic code at the levels of replication and codon usage.Supplementary material to this paper is available in electronic form.Reviewing Editor: Dr. Edward Trifonov 相似文献
18.
Acculturation, culture fatigue, and cultural evolution have all been offered as explanations of the Hawaiian Cultural Revolution. All of these are concerned with cultural processes. The relevant historical and ethnographic data on this unique event are summarized here, and a different interpretation of them is offered. This interpretation is that the events that precipitated the so-called Cultural Revolution can also be regarded as political responses deliberately made by the legitimate government of Hawaii to alleviate a severe political and economic crisis. 相似文献
19.
Lake Hayq was previously described as having exceptionally clearwater and very low phytoplankton biomass. It is now very different,with a shallow euphotic depth and abundant phytoplankton. Zooplanktonpopulations have changed as well; Daphnia and Diaphanosoma wererecorded before, whereas we found no Cladocera. Among the possiblecauses for this change in trophic status is the introductionof the planktivorous fish Oreochromis niloticus. 相似文献
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