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1.
One of the leading challenges for contemporary anthropology is to try to contribute to an understanding of the interaction between indigenous and exogenous socio‐cultural orders, especially at the frontiers of globalisation. Here I review three recent attempts to do so: (1) a model of structural transformation as developed by Marshall Sahlins; (2) a model of articulation as developed by James Clifford; (3) a model of ‘adoption’ proposed by Joel Robbins. As a test case for these models, I consider them in relation to some recent developments in local segmentary politics and verbal art in the Ku Waru region of Highland New Guinea. I show that all three models are in certain respects inadequate for understanding those developments, and offer some proposals as to what kinds of theory might be more adequate to the task.  相似文献   
2.
Two seemingly disparate areas of English language structure—the grammar of reported speech and of textual cohesion—are functionally related in that both entail a distinction between "wording" and "meaning." This is consistent with the Western ideological disjunction between language and reality, talk and action. Neither these language structures nor this linguistic ideology are found among the Ngarinyin people of northwestern Australia, suggesting a Whorfian hypothesis about their possible interrelationship.  相似文献   
3.
The oxygen dependence of mitochondrial respiration was investigated using suspensions of mitochondria and quiescent ventricular myocytes isolated from adult rat hearts. A new optical method was used to determine oxygen concentration in the suspending media. The P50 for respiration for coupled mitochondria at a high [ATP]/[ADP].[Pi] ratio and oxidizing glutamate/malate was 0.45 +/- 0.03 microM but was increased to 0.57 +/- 0.02 microM by the addition of succinate to the substrate mixture. This value was decreased to less than 0.06 +/- 0.01 microM when the ATP/ADP.Pi ratio was decreased with the uncoupler, carbonyl cyanide p-trifluoromethoxyphenylhydrazone. The P50 value in resting myocytes was 2.23 +/- 0.13 microM at a Vmax of 13.22 +/- 1.38 nmol of O2/g, dry weight/min. During resting conditions, the creatine phosphate/creatine and ATPfree/ADPfree ratios were high in these cells, 6.81 +/- 1.11 and 1131 +/- 185, respectively. Addition of 1 mM Ca2+ to the suspending media increased the P50 by 50% whereas respiration rose by only 10%. Respiratory rate was increased up to about 10-fold by uncoupling the cells, but the P50 increased by less than 3-fold. When these uncoupled cells were inhibited with Amytal to lower the rate of oxygen consumption to that of resting cells, the P50 fell to 1.25 +/- 0.14 microM. Diffusion models indicate that in resting myocytes, the oxygen concentration difference from sarcolemma to cell core was approximately 1.84 microM with an additional difference of about 0.27 microM attributed to the unstirred layer of media surrounding each cell. The intracellular oxygen diffusivity coefficient in myocytes was calculated to be 0.30 x 10(-5) cm2/s. The results show that the oxygen dependence of respiration is modulated by the cellular metabolic state. At near maximal levels of respiration or on recovery from hypoxic episodes, oxygen diffusion may become an important determinant of the oxygen dependence of myocardial respiration.  相似文献   
4.
The biocontrol properties of Trichoderma species are well documented, but their effectiveness in antagonism of the problematic Sclerotium cepivorum, the causal agent of white rot in Allium species, appears limited with reports of significant control only relating to deliberately-mutated strains of Trichoderma. Our previous studies have indicated the possibility of using selected naturally-occurring strains of the antagonist in the suppression of other diseases; now in vitro and controlled environment in vivo studies have indicated that a degree of control of Onion White Rot is possible, and that the selected antagonist strains can be used in integrated treatments with Iprodione to good effect. The possible value of such treatments is considered in light of other approaches to the suppression of this continuing problem.  相似文献   
5.
Previously we reported on the synthesis and properties of a series of highly potent piperidinyl 2-subsituted-3-cyano-1-naphthamide NK1 antagonists that includes 3 and 4. Here we report our efforts to alleviate a troublesome atropisomeric property of those derivatives by introduction of a tethering bridge that, in addition, could be used to lock the resulting cyclic derivatives in a purported NK1 pharmacophore conformation. Using 3 as a starting point, the naphtho[2,1-b][1,5]oxazocine, 17, was found to contain the optimal ring tether size (8) for retaining NK1 activity, was more NK1 versus NK2 selective, and reduced the number of atropisomers from four to two. Cyclic derivatives 29 and 32, which exist as essentially single atropisomers in the purported pharmacophore conformation, were prepared in the closely related naphtho[1,2-f][1,4]oxazocine series as part of an effort to use mono methyl substitution of the tethering bridge as a conformation stabilizing factor. Both 29 and 32 were found to be less active as NK1 antagonists than the non-methylated parent 28 possibly due to methyl group destabilization of receptor interaction. We discuss the above findings in the context of a previously proposed NK1 pharmacophore model and present a further refinement of that model.  相似文献   
6.
Summary : FT is a tool written in C++, which implements the Fourier analysis method to locate periodicities in aminoacid or DNA sequences. It is provided for free public use on a WWW server with a Java interface. Availability : The server address is http://o2.db. uoa.gr/FT Contact : shamodr@atlas.uoa.gr   相似文献   
7.
Length polymorphism in a non-coding spacer (trnLUAA-trnFGAA) in the chloroplast DNA was used in the investigation of the origin of the most common and conspicuous European fern hybrid, Asplenium x alternifolium (Aspleniaceae, Pteridophyta). The origins of A. x alternifolium, the hybrid between A. trichomanes s.l. and A. septentrionale s.l. was studied at three ploidy levels, diploid, triploid and tetraploid. The cpDNA technique allowed us to investigate the mode of hybrid formation between sexual species for the first time over a wide geographic range and with a large sample size. Morphological variation in this hybrid has previously been attributed to different reciprocal parental combinations, and to the influence of chloroplast genes on morphogenesis. Our results demonstrate that one parent, A. septentrionale s.l., acts predominantly as the female parent in these hybrids, with only one population of A. x alternifolium showing reciprocal hybridity. The discovery of predominantly unidirectional hybrid formation in this hybrid may be explained by the different breeding systems of the parental taxa. The role of gametophyte ecology is also assessed.  相似文献   
8.
The Killarney fern Trichomanes speciosum Willd. (Hymenophyllaceae) is unique in possessing both extensive sexual (sporophyte and gametophyte generations present) and asexual (gametophyte only) ranges. It was first discovered in central Europe in 1993 and is represented in this area only by its perennial, vegetatively propagating gametophyte generation. Genetic variation has been investigated at 35 sites. Allozyme diversity is partitioned primarily between, not within, sites. Although genetic variation exists at a fine scale (lt 5 m) within some populations, the results suggest that clones were not intimately associated in these cases. The majority of sites support unique multilocus phenotypes. Where phenotypes were present at more than one site they tended to recur at the next closest site. However, similar phenotypes link eastern and western Pfälzerwald sites up to c. 70 km apart. This pattern of diversity suggests that colonisation was not solely of a “stepping stone” or “leading edge” type. We suggest that during a climatically favourable period, probably the Atlantic hypsithermal, there may have been an explosive colonisation by long-distance dispersal from refugial areas. This was followed by a short period during which sporophyte production, sexual reproduction and local spread were possible. With climatic change, reduction in the available habitat and the loss of the sporophyte generation, different individual genets became fixed within small, favourable, but scattered, sites. The possibility that some central European sites north of the Alps acted as periglacial refugia cannot be discounted, but would appear less likely than (re-) colonisation from the Atlantic fringe.  相似文献   
9.
Sahlins bases his account of Polynesian 'heroic history' partly on the fact that chiefs used the pronoun 'I' in reference to their whole group. Mosko (1992) argues that Sahlins's consequent emphasis on 'encompassment' as the modality of chiefly action is diametrically opposed to Strathern's on 'partibility', the effacement of parts of the person as a condition of action. Drawing on comparative material from the New Guinea Highlands, where big men also use 'I' for their whole group, and on Benveniste's and Urban's accounts of the meaning and use of personal pronouns, I argue instead that moments of both encompassment and partibility are inherent in language, corresponding to two distinct dimensions in which the pronouns are meaningful (the 'direct indexical' and the 'anaphoric'), and that close attention to the interaction between the two can yield new insights into the nature of personhood and social agency.  相似文献   
10.
In a recent paper, two of us discussed diversity patterns and diversification processes in the Azores flora. Triantis et al. (2012, Journal of Biogeography, 39, 1179–1184) challenged our hypothesis that palaeoclimatic differences had an effect on diversification rates and suggested that area, island age and isolation explain diversity patterns. They did not, however, fully address the results from our subsequent paper, in which we showed that diversity patterns evident from phylogeographic studies differ markedly from those suggested by checklists. Checklists are working hypotheses and we suggest that the discrepancies evident between molecular data and checklists may be indicative of deficiencies in our taxonomic understanding of the Azores flora. Patterns of molecular and morphological diversity need to be better understood, and the discrepancies between checklists and molecular data accounted for, before we can establish the relative importance of factors such as palaeoclimate, area, island age or isolation in generating endemic diversity patterns in the Azores flora.  相似文献   
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