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1.
Annelies Moors 《Ethnic and racial studies》2013,36(5):871-887
This article deals with the cultural politics of nationalism. It is argued that both the production and display of embroidered dresses and the particular ways in which these are presented on one set of picture postcards are part of the material formation of the Palestinian nation. Whereas the dresses on these postcards draw attention to a rural heritage that stands for territory and rootedness, the women-bodies presenting these dresses, both in their appearance and through the act of public presentation, express urban modernity. Such a style of representation avoids associations of the rural with “backwardness” and enables the inclusion of elements of the rural in the modern national project. 相似文献
2.
Fruitful exchanges of ideas existed between early 20th century anthropology (volkenkunde) and folklore studies (volkskunde) in the Netherlands. Folklorists proposed using the fieldwork methods and comparative approach of ethnography. Anthropologists thought folklore studies might be able to shed light on survivals of earlier stages in their own society. During the 1930s, however, anthropologists turned their backs on the evolutionist paradigm, while in the wake of National Socialism and its quest for a common Germanic race and culture folklorists limited their cross-cultural comparisons to Europe. Cultural politics in Germany and other European countries in the 1930s and early 1940s directed the concepts, methods and institutionalization of folklore studies, and consequently led to a distancing from the concepts and practice of cultural anthropology. 相似文献
3.
Long-term field studies have revealed considerable behavioural differences among groups of wild Pan troglodytes. Here, we report three sets of cladistic analyses that were designed to shed light on issues relating to this interpopulation variation that are of particular relevance to palaeoanthropology.In the first set of analyses, we focused on the proximate cause of the variation. Some researchers have argued that it is cultural, while others have suggested that it is the result of genetic differences. Because the eastern and western subspecies of P. troglodytes are well differentiated genetically while groups within the subspecies are not, we reasoned that if the genetic hypothesis is correct, the phylogenetic signal should be stronger when data from the eastern and western subspecies are analysed together compared to when data from only the eastern subspecies are analysed. Using randomisation procedures, we found that the phylogenetic signal was substantially stronger with in a single subspecies rather than with two. The results of the first sets of analyses, therefore, were inconsistent with the predictions of the genetic hypothesis.The other two sets of analyses built on the results of the first and assumed that the intergroup behavioural variation is cultural in nature. Recent work has shown that, contrary to what anthropologists and archaeologists have long believed, vertical intergroup transmission is often more important than horizontal intergroup transmission in human cultural evolution. In the second set of analyses, we sought to determine how important vertical transmission has been in the evolution of chimpanzee cultural diversity. The first analysis we carried out indicated that the intergroup similarities and differences in behaviour are consistent with the divergence of the western and eastern subspecies, which is what would be expected if vertical intergroup transmission has been the dominant process. In the second analysis, we found that the chimpanzee cultural data are not only comparable to a series of modern human cultural data sets in terms of how tree-like they are, but are also comparable to a series of genetic, anatomical, and behavioural data sets that can be assumed to have been produced by a branching process. Again, this is what would be expected if vertical inter-group transmission has been the dominant process in chimpanzee cultural evolution.Human culture has long been considered to be adaptive, but recent studies have suggested that this needs to be demonstrated rather than assumed. With this in mind, in the third set of analyses we investigated whether chimpanzee culture is adaptive. We found the hypothesis that chimpanzee culture is adaptive was supported by an analysis of data from the Eastern African subspecies, but not by an analysis of data from the eastern and western subspecies.The results of our analyses have implications for the number of subspecies in Pan troglodytes, the relationship between hominin taxa and Palaeolithic industries, and the evolution of hominin cognition and behaviour. 相似文献
4.
Based on empiric data of breeding success and accurate number trends in The Netherlands, a population model for the black
tern was constructed. This model is based on Leslie matrices. Reproductive parameters from the four most important landscape
types (river landscape, agricultural grasslands, peat marsh and heath land/moors) are used as model input. Highly accurate
national population trend data were used to obtain the best (least square) estimate of overall adult and subadult survival
(resp. 0.849 and 0.595). Estimating survival parameters in this way might be useful for threatened (bird) species, especially
if catching and ringing is difficult or less desired from a conservation perspective. The model shows the actual importance
of the river landscape as the main source for reproductive output of the Dutch black tern population. The prediction model
was subsequently used to test different conservation strategies for the Dutch black tern population. Conservation strategies
ranged from a null scenario (no change in conservation effort) to in- or decreasing the number of rafts in the most productive
landscape (river landscape) to a scenario where breeding success is improved recently in agricultural grasslands via minimizing
disturbance. For all scenarios, the model predicts a slow to rapid population increase in the Dutch black tern population
after 10–20 years. Improving breeding success in agricultural grasslands habitat has the highest added value. 相似文献
5.
Melanin has an important role in the ability of fungi to survive extreme conditions, like the high NaCl concentrations that are typical of hypersaline environments. The black fungus Hortaea werneckii that has been isolated from such environments has 1,8-dihydroxynaphthalene-melanin incorporated into the cell wall, which minimises the loss of glycerol at low NaCl concentrations. To further explore the role of melanin in the extremely halotolerant character of H. werneckii, we studied the effects of several melanin biosynthesis inhibitors on its growth, pigmentation and cell morphology. The most potent inhibitors were a 2,3-dihydrobenzofuran derivative and tricyclazole, which restricted the growth of H. werneckii on high-salinity media, as shown by growth curves and plate-drop assays. These inhibitors promoted release of the pigments from the H. werneckii cell surface and changed the medium colour. Inhibitor-treated H. werneckii cells exposed to high salinity showed both decreased and increased cell lengths. We speculate that this absence of melanin perturbs the integrity of the cell wall in H. werneckii, which affects its cell division and exposes it to the harmful effects of high NaCl concentrations. Surprisingly, melanin had no effect on H. werneckii survival under H2O2 oxidative stress. 相似文献
6.
Prema Kurien 《Ethnic and racial studies》2013,36(2):263-293
This article focuses on the political struggles between Hindu and Muslim Indian immigrant groups in the United States over the definition of "Indianness". Hindu Indian American organizations define India as a Hindu society and are strong supporters of the Hindu nationalist movement in India. Muslim Indian American organizations, on the other hand, view India as a multi-religious and multicultural society. They are striving to safeguard India's secularism and towards this end, have entered into coalitional relationships with lower caste groups. Both types of organizations are working to influence American and Indian politics in line with their respective interests, leading to an exacerbation of the conflict between the two immigrant groups. This article examines the reasons for this development and its implications, both for the development of an Indian American community in the United States and for religion and politics in India. 相似文献
7.
Miles J. A. Leahy Thomas H. Oliver Simon R. Leather 《Agricultural and Forest Entomology》2007,9(2):115-124
1 The feeding behaviour of Hylastes ater was investigated at 15 °C and 20 °C on a range of tree species. The role of an aggregation pheromone and the part played by olfactory cues in food selection was also investigated. 2 A distinct hierarchical preference at both 15 °C and 20 °C such that Pinus radiata > Pinus sylvestris > > Picea abies > > Rubus fruticosus=Betula pendula was shown. 3 Feeding on P. sylvestris led to the highest weight gain, closely followed by P. radiata and P. abies. Slightly elevated feeding was observed at 20 °C compared with 15 °C. 4 Reduced feeding in the presence of B. pendula suggests the possibility of an antifeedant effect and predamaged wood was found to be less nutritious, possibly due to greater plant defences. 5 The role of an aggregation pheromone was not supported. Olfactory cues enabled the detection of woody hosts, although differentiation between host was not observed. 6 These results are likely to be important in helping to design an effective integrated control approach against this pest. 相似文献
8.
Suruliyandi Vijayan Sankarappan Anbalagan Kalimuthu Rekha Sundaram Dinakaran Muthukalingan Krishnan 《Journal of Asia》2019,22(2):568-574
Simulium (Gomphostilbia) agasthyamalaiense sp. nov. is described based on adults, pupae and mature larvae from a medium-flowing stream of Southern Western Ghats, India. This new species is placed in the Simulium batoense species-group of the subgenus Gomphostilbia Enderlein. This new species is characterized in the female by a scutum with three brownish-black longitudinal vittae and the hind basitarsus 5.7 times as long as wide; in the female by the large facets of upper eye with 20 vertical columns and 19 horizontal rows; in the pupa the respiratory gill with medium-long common basal stalk; and in the larva arrowhead-shaped postgenal cleft. Taxonomic notes are provided for this new species and it can be distinguished from closely related species of S. (G.) peteri. Keys are constructed to distinguish this species from ten species of the batoense species-group recorded in India.www.zoobank.org/urn:lsid:zoobank.org:pub:1D1CFEE5-A762-4F68-9EAE-9E31133146C0 相似文献
9.
James T. Warren Michael B. O'Connor Lawrence I. Gilbert 《Insect biochemistry and molecular biology》2009,39(10):677-687
It has long been hypothesized that the oxidation of 7-dehydrocholesterol (7dC), made from dietary cholesterol (C), to 3-oxo-7dC (3-oxo-Δ5,7C) immediately precedes the unknown “Black Box” oxidations that lead to the formation of the first up-stream intermediate exhibiting the highly characteristic ecdysteroid structure of the steroid molting hormone of insects, crustaceans and some other arthropods. Perhaps rate-limiting and under the control of the prothoracicotropic hormone (PTTH), the biosynthesis of 3-oxo-7dC and its subsequent oxidative modifications have been difficult to study because of their apparent instability, i.e. no intermediates between 7dC and the diketol (3-oxo-25,22,2-trideoxyecdysone) have ever been observed or identified in insect prothoracic gland incubations with radiolabelled precursors. However, we show that 3-oxo-7dC can be converted into lipophilic, photosensitive, ketone-blocked (PSKB) ketal derivatives which will release 3-oxo-7dC when and where desired following brief irradiation with innocuous long-wave (365 nm) UV-light both in vivo and in vitro. In this manner, 3-oxo-7dC is quickly and efficiently incorporated into ecdysteroids by adult male and female Drosophila raised on a diet containing the PSKB ketals and in prothoracic glands of Manduca sexta incubated with the ketals emulsified into media. The instability of 3-oxo-7dC and its spontaneous transformation into extensively electron-delocalized intermediates will be discussed in relation to a possible mechanism of the Black Box oxidations eventually leading to the production of the active molting hormone 20-hydroxyecdysone (20E). 相似文献
10.
The involvement of apoplastic invertase (Ap Inv) and sucrose synthase (SuSy) in the somatic embryo development of black spruce (Picea mariana) was investigated under different maturation conditions. Replacing 6% sucrose with 3% or 1% sucrose in the maturation medium drastically decreased Ap Inv activity and amount in embryogenic tissues. This was accompanied by a decrease in the hexose pool that resulted in a lower starch deposition and protein amount in embryogenic tissues together with a lower embryo production. Conversely, SuSy activity was stable during maturation regardless of the sucrose concentration used in the medium. The presence of an extracellular enzyme responsible for sucrose hydrolysis in the maturation medium was also verified. An immunodetection experiment with anti-acid invertase antibodies revealed the presence of an active 53 kDa polypeptide in the medium, which had a similar molecular mass to that of the Ap Inv polypeptide found in embryogenic tissues. Utilization of sucrose from the medium by the tissues was also studied using labelled 14C-sucrose. Distribution of the radioactivity between tissular sucrose, glucose, and fructose showed that sucrose was diffused into the cell wall of embryogenic tissues and partly hydrolyzed by Ap Inv. These results show that the utilization of sucrose from the medium, the Ap Inv activity in embryogenic tissues, and the release of an active invertase into the medium operate together for the utilization of the carbohydrates during somatic embryo development in black spruce. 相似文献
11.
A distinctive feature of ecological restoration is that the human presence in the natural landscape can be perceived as beneficial and not necessarily as harmful. Consequently, negotiations between heterogeneous actors involved and reactions to developments in different ecosystems become part of the scientific practice of restoration. This paper discusses some implications of restoration practice for the science of ecology in connection with recent debates about a new mode of knowledge production in science. I illustrate how different types of expertise from several backgrounds can be fed into each step of restoration implementation via alternate phases of selection and of corroboration by use to expose it to further observation in order to develop more scientifically and socially robust restoration strategies. 相似文献
12.
Nodulation abilities of bacteria in the subclasses Gammaproteobacteria and Betaproteobacteria on black locust (Robinia pseudoacacia) were tested. Pseudomonas sp., Burkholderia sp., Klebsiella sp., and Paenibacillus sp. were isolated from surface-sterilized black locust nodules, but their nodulation ability is unknown. The aims of this study were to determine if these bacteria are symbiotic. The species and genera of the strains were determined by RFLP analysis and DNA sequencing of 16S rRNA gene. Inoculation tests and histological studies revealed that Pseudomonas sp. and Burkholderia sp. formed nodules on black locust and also developed differentiated nodule tissue. Furthermore, a phylogenetic analysis of nodA and a BLASTN analysis of the nodC, nifH, and nifHD genes revealed that these symbiotic genes of Pseudomonas sp. and Burkholderia sp. have high similarities with those of rhizobial species, indicating that the strains acquired the symbiotic genes from rhizobial species in the soil. Therefore, in an actual rhizosphere, bacterial diversity of nodulating legumes may be broader than expected in the Alpha-, Beta-, and Gammaproteobacteria subclasses. The results indicate the importance of horizontal gene transfer for establishing symbiotic interactions in the rhizosphere. 相似文献
13.
Luis G. García-Montero Miguel . Casermeiro Jos L. Manjn Isabel Hernando 《Mycological Research》2007,111(6):734-739
There are very few studies on Tuber melanosporum associated with Cistus populations. In central Spain, we confirm that C. laurifolius shows carpophore production of Tuber melanosporum. This study demonstrates a correlation between T. melanosporum production and the size of the 41 burns, with burn size explaining 26 % of the variability in carpophore production. However, statistical analysis of the results indicates that average production of 21 burns with Cistus laurifolius is 73 % lower than the production of 20 burns associated with Quercus/Corylus without Cistus laurifolius in this zone, respectively. C. laurifolius develops small burns, which has an impact on their carpophore production, and their soils have 92 % less active carbonate than the burns associated with Quercus/Corylus in this zone, respectively. The low levels of active carbonate allow Cistus laurifolius to grow, but impair Tuber melanosporum production. We thus provide a mechanism, based on the inability of Cistus laurifolius to grow in highly carbonated soils, which contradicts the well-known fact that C. laurifolius might act as a transmitter of Tuber melanosporum mycorrhizae. These results indicate that this rockrose can not be considered a useful species for truffle culture. We thus recommend that particular attention should be given to the concentration of active carbonate present in the soil in future studies on the relationship between Cistus species and truffles. 相似文献
14.
Somjintana Tourtip Grant D. Stentiford Siriporn Sriurairatana Kallaya Sritunyalucksana 《Journal of invertebrate pathology》2009,102(1):21-29
A new microsporidian species, Enterocytozoon hepatopenaei sp. nov., is described from the hepatopancreas of the black tiger shrimp Penaeus monodon (Crustacea: Decapoda). Different stages of the parasite are described, from early sporogonal plasmodia to mature spores in the cytoplasm of host-cells. The multinucleate sporogonal plasmodia existed in direct contact with the host-cell cytoplasm and contained numerous small blebs at the surface. Binary fission of the plasmodial nuclei occurred during early plasmodial development and numerous pre-sporoblasts were formed within the plasmodium. Electron-dense disks and precursors of the polar tubule developed in the cytoplasm of the plasmodium prior to budding of early sporoblasts from the plasmodial surface. Mature spores were oval, measuring 0.7 × 1.1 μm and contained a single nucleus, 5-6 coils of the polar filament, a posterior vacuole, an anchoring disk attached to the polar filament, and a thick electron-dense wall. The wall was composed of a plasmalemma, an electron-lucent endospore (10 nm) and an electron-dense exospore (2 nm). DNA primers designed from microsporidian SSU rRNA were used to amplify an 848 bp product from the parasite genome (GenBank FJ496356). The sequenced product had 84% identity to the matching region of SSU rRNA from Enterocytozoon bieneusi. Based upon ultrastructural features unique to the family Enterocytozoonidae, cytoplasmic location of the plasmodia and SSU rRNA sequence identity 16% different from E. bieneusi, the parasite was considered to be a new species, E. hepatopenaei, within the genus Enterocytozoon. 相似文献
15.
Nigel C. Veitch Peter C. Elliott Geoffrey C. Kite Gwilym P. Lewis 《Phytochemistry》2010,71(4):479-2590
Four flavone glycosides isolated from extracts of the leaves of Robinia pseudoacacia (Leguminosae) were characterised by spectroscopic and chemical methods as the 7-O-β-d-glucuronopyranosyl-(1 → 2)[α-l-rhamnopyranosyl-(1 → 6)]-β-d-glucopyranosides of acacetin (5,7-dihydroxy-4′-methoxyflavone), apigenin (5,7,4′-trihydroxyflavone), diosmetin (5,7,3′-trihydroxy-4′-methoxyflavone) and luteolin (5,7,3′,4′-tetrahydroxyflavone). Assignment of glycosidic 1H and 13C resonances in their NMR spectra was facilitated by 2JHC correlations detected using the H2BC (heteronuclear two-bond correlation) pulse sequence. Spectroscopic analysis of two known triglycosides, acacetin 7-O-β-d-glucopyranosyl-(1 → 2)[α-l-rhamnopyranosyl-(1 → 6)]-β-d-glucopyranoside (previously unrecorded from this species) and acacetin 7-O-β-d-xylopyranosyl-(1 → 2)[α-l-rhamnopyranosyl-(1 → 6)]-β-d-glucopyranoside (‘acacetin trioside’), enabled inconsistencies in the literature relating to these structures to be resolved. Comparison of the flavonoid chemistry of leaves and flowers of R. pseudoacacia using LC-UV and LC-MS showed that flavone 7-O-glycosides, particularly of acacetin, predominated in the former, whereas the latter comprised mainly flavonol 3,7-di-O-glycosides, including several examples new to this species. Tissue dependent differences in flavonoid chemistry were also evident from the glycosylation patterns of the compounds. 相似文献
16.
Black scale Saissetia oleae (Olivier) (Hemiptera: Coccidae) is a widespread olive pest in California and Europe. Metaphycus lounsburyi (Howard) (Hymenoptera: Encyrtidae) is often one of its main parasitoids. Augmentative releases of M. lounsburyi have been proposed in those areas in which biological control is ineffective. In this paper, we study the relationship between black scale and M. lounsburyi in the field. According to our data, M. lounsburyi parasitizes mainly ovipositing females of black scale. Parasitism rates of ovipositing females reach high levels. In those scales, M. lounsburyi develops as a gregarious parasitoid, with an average of 13 and a maximum of 40 parasitoids developing per scale. The secondary sex ratio is female biased (proportion of males = 0.13) and appears to be brood size dependent. Metaphycus lounsburyi eggs are encyrtiform; however, its egg load is much higher than other Metaphycus that also parasitize black scale. The implications of these results on the behavioral ecology of M. lounsburyi and its use in biological control of black scale are discussed. 相似文献
17.
Electron microscopy of ultrathin serial sections was used to determine the structure and anatomy of the eriophyid gall mite, Cecidophyopsis ribis, the vector of the agent of black currant reversion disease. The composite picture derived from these studies has determined the location of the food canal, and major internal organs of the mite. Detailed ultrastructural studies on the anterior of suitably orientated mites has also provided detailed information on the geometry and complex structure of three sets of stylets in the feeding apparatus. No evidence was found of structures resembling virus-like particles or of other described plant pathogens in the feeding apparatus and food canal of mites obtained from black currant plants affected with reversion disease. However, little or no food was apparently present in the food canal of most mites examined. This is the first detailed report of the anatomy and the ultrastructure of the mouthparts of this important plant pest and vector. 相似文献
18.
Alexander Nützel Royal H. Mapes 《Lethaia: An International Journal of Palaeontology and Stratigraphy》2001,34(2):143-162
A horizon in the late Visean Ruddle Shale from Arkansas contains the oldest well-preserved gastropod protoconchs known from the Americas. The gastropod fauna consists of a diverse larval shell assemblage and a low diversity assemblage of juvenile gastropods that probably had a benthic life habit. Gastropod larval shells are always isolated, i.e. the gastropods did not complete their life cycle (no metamorphosis) and were unable to become benthic. This was caused by unfavorable environmental conditions on the soft muddy bottom that was probably due to anaerobic to exaerobic conditions. The absence or scarcity of bioturbation caused by invertebrate detritus or sediment feeders in both shale and concretions (formed before compaction) favored preservation of the delicate larval shells. The lack or scarcity of infauna and bioturbation as well as the low diversity of the presumed benthos supports an interpretation of a quasi-anaerobic to exaerobic benthic environment. The superbly preserved larval shells demonstrate that there are more caenogastropod clades present in the late Palaeozoic than suggested previously. Some larval shell types have an openly coiled first whorl followed by a planktotrophic larval shell; openly coiled initial whorls are unknown from modern caenogastropods. The vetigastropods have a smooth protoconch of two whorls clearly demarked from the following whorls - a pattern unknown in modern vetigastropods which have a protoconch of less than one whorl and build no larval shell during their planktonic stage. This could indicate a link between Palaeozoic vetigastropods and the caenogastropods. 相似文献
19.
Green TB White S Rao S Mertens PP Adler PH Becnel JJ 《Journal of invertebrate pathology》2007,95(1):26-32
A cypovirus from the black fly Simulium ubiquitum (SuCPV) was isolated and examined using biological and molecular techniques. SuCPV produces small (typically 0.25mum), polyhedral shaped inclusion bodies (polyhedra), in which the virus particles become multiply embedded. SuCPV is the third cypovirus isolated from Diptera, but the first from Simuliidae that has been characterized using molecular analyses. SuCPV has a genome composed of 10 segments of dsRNA, with an electrophoretic migration pattern that is different from those of recent UsCPV-17 and CrCPV-17 isolates from the mosquitoes Uranotaenia sapphirina and Culex restuans, respectively. The SuCPV electropherotype appears to show significant differences from those of the previously characterized lepidopteran cypoviruses. Sequence analysis of SuCPV segment 10 shows that it is unrelated to either of the two CPV isolates from Diptera or to the CPV species for which Seg-10 has been previously characterized from Lepidoptera. A comparison of the terminal regions of SuCPV genome segments to those of CPV-1, 2, 4, 5 14, 15, 16, 17, 18, and 19 also revealed only low levels of conservation. We therefore, propose that SuCPV is classified within a new Cypovirus species, which we have tentatively identified as Cypovirus-20. We have therefore referred to this virus isolate as S. ubiquitum CPV-20 (SuCPV-20). 相似文献
20.
A newly discovered microsporidium infecting the black vine weevil, Otiorhynchus sulcatus (F.) (Coleoptera: Curculionidae), provisionally placed in the genus Canningia, was studied to determine its impact on O. sulcatus. O. sulcatus populations from several locations were sampled and evaluated for microsporidiosis. A very low prevalence of the disease was observed in all locations surveyed (<3.0%). Laboratory studies were conducted by orally exposing both larvae and adults of O. sulcatus to varying concentrations of Canningia sp. spores. Larval bioassays at a variety of dosages (0, 10, etc.) were performed to evaluate pathogen infectivity, larval survival and growth. Adult bioassays (dosages: 0, 10, etc.) were performed to evaluate longevity, fecundity and mechanisms of vertical pathogen transmission. Larvae and adults were infected in all spore treatments. Larval growth was significantly reduced at dosages above 10 spores/larva. Adults infected at all dosages experienced high levels of mortality and fecundity was reduced to zero. Greenhouse trials were performed to determine if larvae feeding in soil acquired infections when spores were topically applied as a drench application (0, 105, 106, 107 spores/pot). Established larvae feeding on plant roots in pots developed infections when exposed to drench treatments of 106 and 107 spores/pot after 14-21 days. Canningia sp. is an acute pathogen of O. sulcatus infective to both larvae and adults. Topically applied spores also infected larvae feeding on roots in soilless potting media, suggesting the possibility of using this pathogen in a microbial control program. 相似文献