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1.
This study addresses whether or not nematode assemblages inhabiting the soft sediment in abyssal nodule fields are unique and differ from those occurring in the nodule-free abyssal areas. This question is important for the evaluation of possible diversity losses caused by nodule mining operations. The analysis involved seven datasets at genus-level of nematode assemblages from three nodule-bearing abyssal areas in the Pacific (the Clarion-Clipperton Fracture Zone or CCFZ, and the Peru Basin) and the Indian Ocean (CIOB), and five datasets from nodule-free abyssal regions (the Atlantic Ocean). Only individuals identified to valid genera were used in the analysis. Overall, more than 20,000 nematode individuals from 90 samples were analysed. The analyses showed that the nematode communities in the nodule fields did differ from those in the nodule-free abyss. The nodule fields are characterized by a higher microhabitat heterogeneity, which resulted in a higher diversity of nematode communities inhabiting the nodule fields. However, one set of dominant taxa (Monhysteridae, Microlaimus, Acantholaimus, Theristus and Desmoscolex) was identical for both the nodule-bearing and nodule-free abyss, although some genera were strongly and significantly associated with either the nodule-free abyss (Microlaimus) or the nodule-bearing abyssal regions (Capsula). On the other hand, nematode assemblages at nodule-bearing and nodule-free sites within the nodule-bearing abyss proved to be similar at the genus level. This makes it possible for the nodule-free sites to serve as donors of colonizers for the mining-impacted nodule-bearing abyss. However, this suggestion has to be treated with caution, because the species-level differences have not been tested yet.  相似文献   

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Abundance and composition of the near-bottom zooplankton between 10 and 100 metres above the bottom (mab) were studied in the Levantine Basin, eastern Mediterranean, during four cruises of RV Meteor in June 1993, January 1998, April/May 1999 and October 2001. Copepoda made up 91% of all zooplankton caught. A strong dominance of one single species was observed on all cruises, with Lucicutia longiserrata reaching 50–90% of all Copepoda except in 1993, when Subeucalanus monachus was the most abundant species, with more than 90% of all Copepoda. The year 1993 was also exceptional in terms of total zooplankton abundance, being more than one order of magnitude higher than in the other years. Vertical differences in abundance and composition were small and did not indicate a near-bottom effect or a specialized benthopelagic zooplankton community in the layers sampled.  相似文献   

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We examined four species of sea pen (Anthoptilum grandiflorum, Halipteris finmarchica, Pennatula aculeata and Pennatula grandis) collected from the Gulf of St. Lawrence and mouth of the Laurentian Channel, eastern Canada. An exponential length–weight relationship was found for all four species, where growth in weight was progressively greater than growth in length with increasing colony size. Halipteris finmarchica, P. grandis and P. aculeata presented the better allometric fits, explaining over 80% of the variance. In addition, a count of growth increments visible in transverse sections in 86 A. grandiflorum and 80 P. aculeata samples was made. Presumed ages ranged between 5 and 28 years for A. grandiflorum and 2 and 21 years for P. aculeata. Radiocarbon assays were inconclusive and could not be used to confirm these ages; further age validation is required. Radial growth of the rod is slow during the first years, increasing at intermediate sizes of the colony and slowing down again for large colonies. Similar results were obtained from the relationship between colony length and number of growth increments where a logistic model was the best fit to the data. On average Spearman’s rank correlations showed 11% of shared variance between sea pen length or weight and environmental variables. Bottom temperature and salinity, depth and summer primary production were significantly correlated to sea pen size for most species.  相似文献   

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The Dodo Raphus cucullatus, a giant flightless pigeon endemic to Mauritius, became extinct in the late seventeenth century, and so rapid was the birds’ disappearance, that by the beginning of the nineteenth century even its very existence was questioned. Only four specimens were then recorded in European museums, of which the most famous was the Tradescant or Oxford Dodo, now in the Oxford University Museum of Natural History. It comprised the head and one foot, and unique soft tissue in the form of skin and traces of feathers. The history of this specimen is reviewed, including the still unresolved question of how it came to Britain, and we provide evidence to show that it was stuffed but probably never mounted. The changes of ownership, and its cataloguing and curation in the different museums are also described, along with its varying roles in entertainment, education and research from the earliest years until the nineteenth century. This is part one of a two-part article; the second deals with the Tradescant Dodo from its dissection in the 1840s until the present day.  相似文献   

6.
The authors characterize the filmed dreamscapes of John Sayles though a structured interview with the screenwriter/director and an analysis of cinematographic and story line techniques utilized in creating dreamscapes in two of his films. The filmmaker uses complex techniques to produce believable dreams in otherwise naturalistic films by isolating the dream sequence and altering sound, color, cinematography, story, time, visual perspective and physical properties of the perceived external reality of the dream. This perceptual and orienting framework required to produce a believable dream on film may reflect innate characteristics of the dream state.  相似文献   

7.
John Joly was an Irish engineer and geologist who in the 1880s attempted to explain the formation of Cambrian markings known as Oldhamia to the freezing of sediment and the development of surface frost. He also noted differences in the preservation of two forms of Oldhamia when found together in the same bed; these were either as a positive or negative. Oldhamia also inspired Joly to write a sonnet in which he considered geochronology, denudation and the history of life. A detailed interpretation of Joly's sonnet is provided for the first time.  相似文献   

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In this article, I am interested in how belief and religious materiality—sacred objects, places, infrastructures and digital media—are entangled in globalisation processes. Drawing on a case study of the John of God spiritual movement, I analyse the ways in which places and objects that have recently acquired sacred status enter into older, more established global spiritual networks, and by doing so are able to travel and ‘settle’ elsewhere. I argue that if we want to make sense of the place of religion in the world today, we need to link two fields of research on religion which have mostly developed separately: the fields of Material Religion and Globalisation of Religion. Furthermore, I contend that it is precisely because of its (mostly mobile) materiality that the John of God movement was able to survive somewhat after its charismatic leader was sentenced and jailed for sexual crimes in 2019.  相似文献   

11.
George Gillespie 《Dreaming》2000,10(3):149-160
This is an analysis of a religious experience in the night recorded in the journal of John Woolman, a colonial Quaker. As a basis for analysis, I try to clarify the data of Woolman's experience without presuppositions about causes, states of consciousness, three-dimensional space, or meaning. I then study the phenomena in the light of what we know about perception, dreaming, hallucinatory geometric forms, light, and other people's comparable experiences. Because different modalities of his experience appear to be in different states at the same time, I examine each part of his experience separately. There is discussion of the relationship of dreams to visions and hallucinations, the concept of discrete states of consciousness, and the distinction between simulation and authentic experience while dreaming. The article is both an analysis of a religious experience recorded in 1757 and a discussion of methods of analysis.  相似文献   

12.
Recent research in epidemiology has identified a number of factors beyond access to medical care that contribute to health disparities. Among the so-called socioeconomic determinants of health are income, education, and the distribution of social capital. One factor that has been overlooked in this discussion is the effect that stigmatization can have on health. In this paper, I identify two ways that social stigma can create health disparities: directly by impacting health-care seeking behaviour and indirectly through the internalization of negative interpersonal judgments. I then argue that social arrangements that foster self-respect can reduce the impact of stigmatization on health disparities. I conclude by showing how John Rawls' conception of justice can be used to address the intersection of stigma, health, and self-respect, in contrast to critics of his position, who have seen him as excessively focused on the allocation of material goods.  相似文献   

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Øverland G 《Bioethics》2007,21(7):355-363
In 1975 John Harris envisaged a survival lottery to redistribute organs from one to a greater number in order to reduce number of deaths as a consequence of organ failure. In this paper I reach a conclusion about when running a survival lottery is permissible by looking at the reason prospective participants have for allowing the procedure from a contractual perspective. I identify three versions of the survival lottery. In a National Lottery, everyone within a jurisdiction is a candidate for being a donor for everyone else, disregarding all differences between individuals' eventual possibility of needing an organ. In a Group Specific Lottery, it is a question of running a lottery among members of a specific group who share the same probability of getting organ failure. In a Local Lottery one randomises among individuals who are already in need of a new organ but who happen to be compatible and in need of different organs. While the first is vulnerable to considerations of fairness, it is difficult to perceive a feasible way to implement the second option that does not come with a host of unwelcome consequences. I argue, however, that it is permissible to run Local Lotteries.  相似文献   

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The opsin from the John Dory Zeus faber rod visual pigment (maximum spectral sensitivity =492 nm) was cloned and sequenced. Comparison of the John Dory rod opsin sequence with those from other fish with blue-shifted scotopic spectral sensitivity provides further evidence for the spectral tuning of this group of visual pigments.  相似文献   

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Microbially induced sedimentary structures (MISS) are an important facet of recent paleoichnological work because of their taphonomic implications. MISS are extensively studied in terms of their formation processes, recognition in the ancient record, and their diverse morphologies. Classification and terminology schemes are based on their appearance and mode of formation; however, the taxonomic treatment of MISS remains debated. Traditionally MISS have been considered sedimentary structures, and arguments have been made that they cannot be treated as trace fossils under the International Code of Zoological Nomenclature (ICZN) due to MISS being formed by communities of microbiota including algae, cyanobacteria, and others, rather than a single tracemaker. Here, we reexamine MISS using an ichnotaxonomic approach and apply ichnologic terminology and binomial names. Upon reexamining the holotype of Kinneyia Walcott, a genus commonly used to describe some MISS, we argue it cannot be used to correctly describe wrinkle or ripple-like features seen in MISS, and we agree with previous authors that Kinneyia is likely not biogenic in origin. We here assign a new ichnogenus and ichnospecies, Rugalichnus matthewii, to ripple-like sedimentary wrinkle marks known as MISS, separating them from the nomen dubium genus Kinneyia.  相似文献   

17.
This study describes the effects of desiccation and rehydration on the water content, haemolymph volume (per cent), osmolarity, and concentrations of Na, K, Mg, and Ca in the haemolymph of the lone star tick, Amblyomma americanum.The water content percentages of ‘severely desiccated’, ‘moderately’ and ‘fully hydrated’ ticks were 46·0, 52·8, and 60·3 per cent respectively. The lowest and highest of these were near the minimum and maximum possible.The haemolymph volume (per cent) of ‘severely desiccated’ ticks was regulated near the level of ‘moderately hydrated’ ticks despite significant decreases in total body water content and increases in osmolarity and concentration of sodium. Conversely, the change from ‘severely desiccated’ to ‘moderately hydrated’ ticks can be viewed as causing an increase in total body water, decrease in blood osmolarity and sodium, but little change in haemolymph volume (per cent).Most of the water taken up by ‘moderately hydrated’ ticks (while becoming ‘fully hydrated’) was added to the haemolymph. At the same time, there was little change in the blood osmolarity or haemolymph concentration of sodium. Conversely, the change of ‘fully’ to ‘moderately hydrated’ ticks was marked by a substantial loss of haemolymph volume (per cent) but little change in osmolarity and concentration of sodium.The concentration of potassium was regulated over the full range of desiccating and hydrating conditions. The lone star tick appeared less able to regulate its haemolymph concentrations of Ca and Mg; both fluctuated at the same rate, but inversely as the haemolymph volume (per cent).It appears that a carefully controlled movement of solutes (Na the predominant cation) between haemolymph and non-haemolymph tissue is intimately linked with haemolymph volume regulation and movement of water into the haemolymph during hydration.  相似文献   

18.
Dr. John Collier traced the discoveries that elucidated the structure and function of the anthrax toxin in his talk "Anthrax Toxin," which was part of the Microbiology Graduate Program Seminar Series at Yale School of Medicine on February 23, 2012. Dr. Collier, Professor of Microbiology and Immunobiology at Harvard University, began by noting the advantages to studying anthrax pathogenesis in a biosafety level-1 lab. This designation does not merely facilitate his research, but also reflects a larger trend of basic research being leveraged to develop translational applications. Basic research on toxin structure has led to the development of a vaccine by Dr. Collier's group. Next-generation prophylactics also may stem from recent discoveries uncovering a role for cellular cofactors that mediate toxin function. Finally, basic research into the toxin substructure has facilitated efforts to change the receptor tropism to target dysregulated cells for therapeutic purposes. The urgency around biodefense agents makes the choice of research priorities a salient issue. As such, this author submits that basic research occupies a unique and lucrative niche driving clinical applications.  相似文献   

19.
Hepatic microsomal cytochrome P-450 from the untreated coastal marine fish scup, Stenotomus chrysops, was solubilized and resolved into five fractions by ion-exchange chromatography. The major fraction, cytochrome P-450E (Mr = 54,300), was further purified to a specific content of 11.7 nmol heme/mg protein and contained a chromophore absorbing at 447 nm in the CO-ligated, reduced difference spectrum. NH2-terminal sequence analysis of cytochrome P-450E by Edman degradation revealed no homology with any known cytochrome P-450 isozyme in the first nine residues. S. chrysops liver NADPH-cytochrome P-450 reductase, purified 225-fold (Mr = 82,600), had a specific activity of 45–60 U/mg with cytochrome c, contained both FAD and FMN, and was isolated as the one-electron reduced semiquinone.Purified cytochrome P-450E metabolized several substrates including 7-ethoxycoumarin, acetanilide, and benzo[a]pyrene when reconstituted with lipid and hepatic NADPH-cytochrome P-450 reductase from either S. chrysops or rat. The purified, reconstituted monooxygenase system was sensitive to inhibition by 100 μM 7,8-benzoflavone, and analysis of products in reconstitutions with purified rat epoxide hydrolase indicated a preference for oxidation on the benzo-ring of benzo[a]pyrene consistent with the primary features of benzo[a]pyrene metabolism in microsomes. Cytochrome P-450E is identical to the major microsomal aromatic hydrocarbon-inducible cytochrome P-450 by the criteria of molecular weight, optical properties, and catalytic profile. It is suggested that substantial quantities of this aromatic hydrocarbon-inducible isozyme exist in the hepatic microsomes of some untreated S. chrysops. The characterization of this aryl hydrocarbon hydroxylase extends our understanding of the metabolism patterns observed in hepatic microsomes isolated from untreated fish.  相似文献   

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This paper argues that both Michael Banton and John Rex were ‘children of empire’, albeit in starkly different ways, and that these differences were at the core of their querulous exchanges over their long careers. The larger issue, however, concerns the impact of colonialism on sociology, especially in its formative years, and conversely, the role of sociology in providing erudite justification for colonialism.  相似文献   

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