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Abstract

The purpose of this work is twofold. First, to analyze the general significance, from an international point of view, of the unilateral establishment by Mexico of its 200‐mile Exclusive Economic Zone as from June 6, 1976, in order to conclude on both its legality and its opportunity, within the framework of, respectively, the present standing of the emerging rules of the new law of the sea and the stage at which the Third United Nations Conference on the Law of the Sea finds itself after four sessions of negotiations. The arguments resorted to by Mexico in order to defend the legality and opportunity of its claim are analyzed in detail. Secondly, a study is made on whether or. not the unilateral claim of establishment of the Exclusive Economic Zone is contrary to Mexico's traditional law of the sea practice, this practice consisting of a permanent policy by Mexico, throughout its independent life, of waiting for international agreements to be concluded, or for international customs to be definitely shaped, before proceeding to the unilateral delimitation of its marine zones.  相似文献   

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Anne Meneley 《Ethnos》2013,78(3):303-326
This article considers the way that a single substance, olive oil, bundles together a set ofqualisigns including luminosity, liquidity, spreadibility, durability, capacity to cleanse, capacity to seal or preserve, capacity to insulate, and notably, a lack of miscibility in water. These qualisigns allow olive oil to operate in several discrete religious contexts in the Mediterranean although the interpretations and the specific qualisigns made salient by particular semiotic metadiscourses are always changing, even though the material substrate remains the same. In contemporary Western discourses of distinction, the positive qualities of olive oil are not those primarily registered by the ordinary senses of taste, touch, and smell, but rather those that are established discursively by expert opinions of various kinds, which attest to olive oil's ‘healthful’ qualities.  相似文献   

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Streptococcus sanguis FW213 carries peritrichous fimbriae (216±28 nm long) and 6 mutants derived from it lack fimbriae but carry peritrichous fibrils with a mean length of 77–4 + 3–9 nm. Both wild type strain and mutants have a ruthenium red staining layer (≤ 14.5±2.9 nm thick) external to the cell wall at the base of the fibrils and fimbriae. The thickness of this layer is strain dependent. Ruthenium red also stains extracellular masses of material, probably extracellular polysaccharide, but not the fimbriae. S. sanguis strain FW 213 adheres to saliva‐coated hydroxyapatite and buccal epithelial cells and is not aggregated by saliva. The 6 non‐fimbriate mutants of FW213 adhered poorly to hydroxyapatite coated in heated whole saliva (S‐SHA) but 3/6 mutants adhered to the same extent or higher than the wild type to S‐SHA coated in unheated saliva, indicating that strain FW213 may carry a non‐fimbriate adhesin and that whole saliva contains a heat sensitive adhesin. All the mutants had a significantly thinner ruthenium red staining layer (RRL) external to the cell wall than the wild type strain FW213, while the cell surface hydrophobicity showed that the mutants were all less hydrophobic than the wild type FW213.  相似文献   

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Abstract

The Third United Nations Conference on the Law of the Sea is addressing problems that involve all of mankind. Yet there are parts of mankind, non‐independent states and special sovereignties, that are not directly represented at the conference, even though their interests will be directly affected by the decisions taken.

There currently arc around 75 non‐independent states and special sovereignties at different stages of political development and with varying forms of association to a metropolitan power. This can create problems of conflicting jurisdiction over ocean space in two areas particularily: the South Pacific and the Caribbean.

The Conference has attempted”; to deal with the problem of the Law of the Sea and non‐independent states in three ways: by granting observer status to national liberation movements and associated states; through the Transitional Provision; and through the Definitional and Final Clauses. However, a universal formula that would guarantee to these states the resource rights recognized in the proposed Treaty has yet to emerge.  相似文献   

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DNA can be divided functionally into three categories: (1) genes — which code for proteins or specify non-messenger RNAs; (2) semons — short specific sequences involved in the replication, segregation, recombination or specific attachments of chromosomes, or chromosome regions (e.g. loops or domains) or selfish genetic elements; (3) secondary DNA — which does not function by means of specific sequences. Probably more than 90% of DNA in the biosphere is secondary DNA present in the nuclei of plants and phytoplankton. The amount of genic DNA is related to the complexity of the organism, whereas the amount of secondary DNA increases proportionally with cell volume, and not with complexity. This correlation is most simply explained by the skeletal DNA hypothesis, according to which nuclear DNA functions as the basic framework for the assembly of the nucleus and the total genomic DNA content functions (together with relatively invariant folding rules) in determining nuclear volumes. Balanced growth during the cell cycle requires the cytonuclear ratio to be basically constant, irrespective of cell volume; thus nuclear volumes, and therefore the overall genome size, have to be evolutionarily adjusted to changing cell volumes for optimal function. Bacteria, mitochondria, chloroplasts and viruses have no nuclear envelope; and the skeletal DNA hypothesis simply explains why secondary DNA is essentially absent from them but present in large cell nuclei. Hitherto it has been difficult to refute the alternative hypothesis that nuclear secondary DNA (whether junk or selfish DNA) accumulates merely by mutation pressure, and that selection for economy is not strong enough to eliminate it, whereas accumulation in mitochondria and plastids is prevented by intracellular replicative competition between their multiple genomes. New data that discriminate clearly between these explanations for secondary DNA come from cryptomonads and chlorarachneans, two groups of algae that originated independently by secondary symbiogenesis (i.e., the merger of two radically different eukaryote cells) several hundred million years ago. In both groups the nucleus and plasma membrane of the former algal symbiont persist as the nucleomorphs and periplastid membrane, respectively. The fact that nucleomorphs have undergone a 200- to 1000-fold reduction in genome size and have virtually no secondary DNA shows that selection against non-functional nuclear DNA is strong enough to eliminate it very efficiently; therefore, the large amounts of secondary DNA in the former host nuclei of these chimaeras, and in nuclei generally, must be being maintained by positive selection. The divergent selection for secondary DNA in the nucleus and against it in nucleomorphs is readily explicable by the skeletal DNA hypothesis, given the different spectrum of gene functions that it encodes.This revised version was published online in October 2005 with corrections to the Cover Date.  相似文献   

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This study compared the cardiac and ventilatory behaviour of disturbed and settled (48 h recovery) ovigerous Cancer pagurus with the behaviour of non‐ovigerous crabs. It also examined the effects of starvation and a sand substrate on ovigerous females. Ovigerous crabs had significantly lower heart rates than non‐ovigerous crabs. This implies that they have a reduced metabolic rate, confirmed by an earlier study which described lower rates of oxygen uptake in ovigerous crabs. Scaphognathite beat frequency was unaffected by either the presence of eggs, starvation or a sand substrate, but the amplitude of ventilatory pressure changes was higher in settled ovigerous females, implying greater force. The duration of periods of reversed ventilation was also substantially extended in ovigerous crabs, and disturbance caused a ten‐fold increase in the frequency of these reversals, resulting in ventilation being carried out in a predominantly reversed direction. It is suggested that these respiratory adaptations serve to ventilate the egg mass. Disturbance also led to a greater elevation of heart rate in ovigerous crabs, indicating that they are more prone to handling stress. Fed ovigerous crabs spent a higher percentage of time ventilating unilaterally; this response was lost following starvation. Starved ovigerous crabs had the lowest mean heart rate, highest mean ventilatory pressures and, when disturbed above a sand substrate, they showed the highest frequency of reversals of ventilation, possibly in association with their efforts to bury their abdomen bearing the egg mass.  相似文献   

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‘Second‐generation decline’ questions the current American faith in the myth of nearly automatic immigrant success. In discussing economic scenarios, positive and negative, for the future of the children of the post‐1965 immigrants, the possibility is proposed that a significant number of the children of poor immigrants, especially dark‐skinned ones, might not obtain jobs in the mainstream economy. Neither will they be willing ‐ or even able ‐ to take low‐wage, long‐hour ‘immigrant’ jobs, as their parents did. As a result, they (and young males among them particularly) may join blacks and Hispanics among those already excluded, apparently permanently, from the mainstream economy. The article also deals with the relations between ethnicity and economic conditions in the USA and with the continued relevance of the assimilation and acculturation processes described by ‘straight‐line theory’. This issue, as well as most others discussed, may also be salient for European countries experiencing immigration, especially those countries with troubled economies.  相似文献   

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The research examines the attitudes of 649 Israeli high school seniors with regard to inter‐ethnic and intra‐ethnic marriage in 1975 and 1990. Gradual but steady increases in the rates of intermarriage over the last decade suggest a lessening of the social distance between the society's major ethnic groups: Sabras (parents born in Israel), Orientals (parents born in Asia or Africa) and Westerners (parents born in America or Europe). On the other hand, a shift in Israel's social ideology ‐ from a melting‐pot policy towards a current emphasis on cultural uniqueness and esprit de corps ‐ may signal a reverse in this trend. The findings of the study indicate significant differences between the attitudes of adolescents in 1975 and 1990 to intra‐ and intermarriage. There is a growing trend towards intramarriage among youth of Oriental and Western origin. In contrast, the second‐generation Sabras of today no longer prefer members of their own group, as they did in 1975, but rather tend to favour intermarrige, especially to Westerners.  相似文献   

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Abstract

The coastal state has jurisdiction over the resources located in the seas and seabed adjacent to its coast. In federal states the question has arisen as to whether the rights in those resources are to be held by the national government or by the subsidiary territorial governments. It has been the focus of political activity and court litigation in the United States and Canada. This paper reviews in detail the status of the offshore claims of the states of the United States and the provinces of Canada. In delimiting these boundaries two systems of law have become relevant—modern public international law and historic common law. Both systems of law have advantages and disadvantages for the courts and interested parties. While the United States has chosen a route that relies very heavily on modern public international law, the Canadian situation is less clear. Litigation now in progress may resolve this issue in Canada by court decree unless a political settlement is reached first. A recent agreement between the Federal Government of Canada and the Gov eminent of Nova Scotia which calls for joint management and revenue sharing may point the way toward such a settlement.  相似文献   

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This article uses representative data on a sample of Australian workers to examine whether non‐English‐speaking‐background [NESB] immigrants are disadvantaged in terms of access to, and participation in, employment‐related training. Results from the estimation of logit models explaining participation in various types of training indicate that NESB immigrant workers have much lower probabilities of receiving training, even after holding other individual and employment characteristics constant. Further, this differential was generally found to be most pronounced for those immigrants with English‐language difficulties. Decomposition of the training differential, however, suggests that part of the explanation for the lesser incidence of training among NESB immigrants may well lie in employer‐based discrimination.  相似文献   

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Abstract

Vital statistics data show a remarkably consistent seasonality in U.S. birth patterns, with peaks in late summer and winter months, and a valley in the spring. An attitude survey of college students suggests that peaks in the actual birth distribution occur in unpopular months in which to give birth; the valley in the actual birth distribution occurs in popular months. This paradoxical finding is named the Season‐of‐Birth Paradox. Explanations to resolve the paradox include biological and psychological components. A psychological mechanism—named the Misinformed Reproducer Hypothesis—is tested using NSFG data from the 1973–75 and 1979–81 cycles. Results suggest that women stop contracepting with the expectation that they will get pregnant almost immediately. When it takes several months on the average for a successful conception to occur, the actual birth distribution is shifted away from the preferred birth distribution. These results suggest that psychological as well as biological mechanisms underlie the consistent seasonality patterns in U.S. births.  相似文献   

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Abstract

Archival data from the MIDUS survey (Brim et al., 2000), a nationally representative sample, on 309 MZ and 333 DZ twin pairs aged 25–74 years were used to test the psychometrics and behavioral genetics of life history strategy. We organized 253 of the originally administered 2,000 questions into 30 scales measuring life history traits (e.g., quality of family relationships and altruism towards kin), medical symptoms (e.g., thyroid problems), personality traits (e.g., neuroticism, extraversion, conscientiousness), and social background (e.g., financial security). A single higher‐order factor, indicating a general life history strategy, composed of three lower‐order factors, was replicated. Factor analyses were then performed on the genetic variance‐covariance matrices. We found that (a) a single higher‐order factor explained the preponderance of the genetic correlations among the scales and (b) this higher‐order factor was itself 68 percent heritable and accounted for 82 percent of the genetic variance among the three component lower‐order factors.  相似文献   

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Fructose1,6diphosphate (FDP) is a glycolytic intermediate which has been theorized to increase the metabolic activity of ischemic tissues. Here we examine the effects of externally applied FDP on cardiomyocyte uptake and metabolism. Adult rat cardiomyocytes were isolated and exposed to varying concentrations (0, 5, 25 and 50 mM) of FDP for either 1, 16 or 24 h of hypoxia (95% N2/5% CO2), each time period followed by a 1 h reoxygenation (95% air/5% CO2). The uptake of FDP by rat cardiomyocytes was more concentrationdependent than timedependent. Furthermore, the uptake of FDP by the cardiomyocytes was similar in the hypoxia and normoxia treated cells. Alamar Blue, a redox indicator that is sensitive to metabolic activity, was used to monitor the effects of the FDP on cardiomyocyte metabolism. In the 1 h hypoxia or normoxia group, the 5, 10 and 25 mM FDP showed a significant increase in metabolism compared to the control cells. When the length of hypoxia was extended to 16 h, all doses of FDP were greater than control. And at the 24 h hypoxia or normoxia time period, only the 10, 25 and 50 mM FDP groups were greater than control. The results indicate a non-linear trend between the external concentration of FDP and the changes noted in metabolism. The findings from this study indicate that a narrow concentration range between 5–10 mM augments cardiomyocyte metabolism, but higher or lower doses may have little additional affect.  相似文献   

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The docking of synaptic vesicles on the presynaptic membrane and their priming for fusion with it to mediate synaptic transmission of nerve impulses typically occur at structurally specialized regions on the membrane called active zones. Stable components of active zones include aggregates of macromolecules, ‘active zone material’ (AZM), attached to the presynaptic membrane, and aggregates of Ca2+-channels in the membrane, through which Ca2+ enters the cytosol to trigger impulse-evoked vesicle fusion with the presynaptic membrane by interacting with Ca2+-sensors on the vesicles. This laboratory has used electron tomography to study, at macromolecular spatial resolution, the structure and function of AZM at the simply arranged active zones of axon terminals at frog neuromuscular junctions. The results support the conclusion that AZM directs the docking and priming of synaptic vesicles and essential positioning of Ca2+-channels relative to the vesicles'' Ca2+-sensors. Here we review the findings and comment on their applicability to understanding mechanisms of docking, priming and Ca2+-triggering at other synapses, where the arrangement of active zone components differs.  相似文献   

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