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1.
This article examines the potential threat of marine pollution caused by offshore oil and gas development activities in the disputed areas of the South China Sea (SCS) and the Spratly Islands. After addressing the potential threat of marine pollution, it discusses the legal obligations and political commitment of the SCS littoral states regarding the protection of the marine environment in the area. The role that Taiwan can play in these matters is also examined.  相似文献   

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The two states in the Philippines v. China Case have continually reaffirmed in multiple documents and the 2002 Declaration on the Conduct of Parties in the South China Sea that they agreed to resolve their disputes in the South China Sea through consultations and negotiations. However, the Arbitral Tribunal in its Award on Jurisdiction held that no obligation of negotiation was provided for in these instruments because they were not legally binding agreements. Moreover, the Tribunal found that the Philippines had satisfied the “obligation to seek a solution through pacific means, including negotiation.” There are problems and deficiencies in the reasoning of the Tribunal respecting these findings.  相似文献   

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A psittacosis epidemic linked to fulmar hunting occurred on the Faroe Islands in the 1930s. This study investigates a plausible explanation to the 20% human mortality in this outbreak. Phylogenetic analysis showed that Chlamydia psittaci isolated from fulmars were closely related to the highly virulent 6BC strains from psittacines and are compatible with an acquisition by fulmars of an ancestor of the 6BC clade in the 1930s. This supports the hypothesis that the outbreak on the Faroe Islands started after naïve fulmars acquired C. psittaci from infected dead parrots thrown overboard when shipped to Europe in the 1930s.  相似文献   

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Two species of neotropical frog, Eleutherodactylus coqui and E. planirostris, have been introduced into the State of Hawaii via the horticulture trade. E. coqui was introduced prior to 1988 and E. planirostris was first reported in 1994. Since these dates frog colonies have rapidly spread accidentally and intentionally and frog abundance within colonies has grown rapidly. Although these frogs were originally restricted to horticulture sites, they are now found in residential areas, resorts and hotels, and public lands. Due to the high potential biomass of introduced frogs there are realistic anthropogenic and ecological concerns associated with the spread of these frogs. Though there currently is a tool that can be used for localized control of frogs in limited circumstances, overall efforts by Federal, State, and County agencies to control the frog in Hawaii have been hampered by limited authorities and funds, disbelief in the threat, and the reluctance to act.  相似文献   

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This article examines China's domestic legal regime for the prevention of vessel source pollution. It pays special attention to the recently adopted Regulation on Prevention and Control of Marine Pollution from Vessels. Potential challenges and emerging issues that China has to confront are addressed, including: application of the legislation to disputed sea areas between China and its neighbors, freedom of navigation in the exclusive economic zone, reduction of emission from ships, and prevention of invasive species from ballast water.  相似文献   

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《Journal of bryology》2013,35(2):154-157
Abstract

We revised both the holotype and an isotype of Riccia teneriffae S.W.Arnell 1962 and additionally revised our own collections of Riccia cavernosa Hoffm. 1795 from the Canary Islands. Since the types of R. teneriffae represent R. cavernosa, and the latter name precedes the former, R. teneriffae should be treated as a synonym of R. cavernosa. In the Canary Islands, R. cavernosa appears to be rare. It has been found on La Gomera, Gran Canaria, Lanzarote, and Tenerife. We report it as new to Fuerteventura. R. cavernosa inhabits ephemeral, thin layers of mud. Very rarely it occurs on basaltic pyroclasts. SEM images of spores are presented. The local distribution is mapped.  相似文献   

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Feral cats have been directly responsible for the extinction of numerous species on islands worldwide, including endemic species of mammals, birds and reptiles. The diet of feral cats in the main habitats of the Canary Islands, as generally occurred on oceanic islands, is mainly composed of introduced mammals, and native species of birds, reptiles and insects. The impact of feral cat upon the endangered species was assessed by evaluating their relative abundance in the cats’ diet and by considering their current conservation status. A total of 68 different preys were identified at species level in all studies carried out in the Canary Islands (5 mammals, 16 birds, 15 reptiles and 32 invertebrates). From all the species preyed by feral cats in the Canary Islands, only four of them are considered threatened by the IUCN Red List of Threatened Species: one endemic bird Saxicola dacotiae and three endemic giant lizards, Gallotia simonyi, Gallotia intermedia, and Gallotia gomerana. Although some efforts on management control have been carried out, it is necessary to enforce these conservation activities on those areas of Tenerife, La Gomera and El Hierro where giant lizards are still present. Furthermore some local areas where endangered bird species are highly predated should be protected. Nevertheless, it is important to take into account the presence of other introduced species such as rats, mice or rabbits in order to avoid problems derived from the hyperpredation process and mesopredator release effect.  相似文献   

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After the first successful transfer of mammalian embryos in 1890, it was approximately 60 years before significant progress was reported in the basic technology of embryo transfer (ET) in cattle. Starting in the early 1970s, technology had progressed sufficiently to support the founding of commercial ET programs in several countries. Today, well-established and reliable techniques involving superovulation, embryo recovery and transfer, cryopreservation, and IVF are utilized worldwide in hundreds, if not thousands, of commercial businesses located in many countries. The mean number of embryos produced via superovulation has changed little in 40 years, but there have been improvements in synchrony and hormonal protocols. Cryopreservation of in vivo-derived embryos is a reliable procedure, but improvements are needed for biopsied and in vitro-derived embryos. High pregnancy rates are achieved when good quality embryos are transferred into suitable recipients and low pregnancy rates are often owing to problems in recipient management and not technology per se. In the future, unanticipated disease outbreaks and the ever-changing economics of cattle and milk prices will continue to influence the ET industry. The issue of abnormal pregnancies involving in vitro embryos has not been satisfactorily resolved and the involvement of abnormal epigenetics associate with this technology merits continued research. Last, genomic testing of bovine embryos is likely to be available in the foreseeable future. This may markedly decrease the number of embryos that are actually transferred and stimulate the evolution of more sophisticated ET businesses.  相似文献   

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There is a growing body of archaeobotanical evidence for the harvesting of millet in Eurasia prior to 5,000 cal. BC. Yet direct evidence for the extent of millet consumption in this time period is rare. This contradiction may be due to millet crops making only a minor contribution to the diet before 5,000 BC. In this article, drawing from recent excavations in North China, we present evidence for millet crops making a substantial contribution to human and animal diets in periods, which correspond chronologically with the time depth of the archaeobotanical record. We infer that in eastern Inner Mongolia, human adoption of millets, which may or may be not related to substantial agriculture, happened at the Early Neolithic, with direct dates between 5,800 and 5,300 cal. BC. Am J Phys Anthropol 149:283–290, 2012. © 2012 Wiley Periodicals, Inc.  相似文献   

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The introduction of several plant pests into Europe in the 19th century with disastrous consequences called for the development of plant quarantine measures to prevent the spread and introduction of pests of plants and plant products. With the purpose of harmonising these measures, and of promoting measures for pest control, the International Plant Protection Convention (IPPC) was developed to address organisms that are both directly and indirectly injurious to plants. It supplies a framework for measures against invasive alien species according to the Convention on Biological Diversity, as far as they are plant pests. Three examples of invasive alien species within the scope of the IPPC are given in the article: the fungus Ceratocystis fagacearum, the pinewood nematode Bursaphelenchus xylophilus and the flatworm Arthurdendyus triangulatus. In its 1997 revision, the IPPC provides for the establishment of International Standards for Phytosanitary Measures, being acknowledged by the Agreement on the Application of Sanitary and Phytosanitary Measures of the World Trade Organisation. Standards most important for invasive alien species are those on pest risk analysis, on requirements for the establishment of pest-free areas, on surveillance, on pest eradication programmes, and on the import and release of exotic biological agents. Phytosanitary regulations in the European Union (EU) have been harmonised and up to now have regulated about 300 plant pests. The requirements also have a protective horizontal effect against the unintentional introduction of many other species, but the existing broader IPPC mandate for alien plant pests is not fully applied by the EU regulations. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

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To identify new indicators of aquatic environmental parameters, both qualitative (the percentages of curved filaments and filaments with ending separation spines) and quantitative morphological parameters (filament and cell size) of a dominant chain colony-forming planktonic diatom (Aulacoseira granulata) were determined in the large, subtropical Pearl River, China. The qualitative parameters mainly exhibited a spatial pattern. The percentage of curved filaments was a good bioindicator of spatial patterns because it varied along the nutrient gradient. Furthermore, the percentage of filaments with ending separation spines was a good bioindicator of seasonal variation. Although the quantitative parameters exhibited a clear temporal pattern, no single parameter could be used as a bioindicator of either spatial or temporal patterns. The link between qualitative and quantitative parameters reflected the internal adaptation mechanism of filamentous diatoms to the external environment. The methods of the present study can also be applied to ecological indicators in other aquatic ecosystems dominated by chain colony-forming diatoms.  相似文献   

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The reaction of bovine pancreatic trypsin with human plasma α2-macroglobulin (α2M) was studied at 25°C, using equimolar mixtures of E and I in 50 mM potassium phosphate buffer, pH 7. The conformational change in α2M was monitored through the increase in protein fluorescence at 320 nm (exc λ, 280 nm). At [α2M]0 = [E]0 = 11.5-200 nM, the fluorescence change data fit the integrated second-order rate equation, (F - F0)/(F - F1) = 1 + ki,obsd2M]0t, indicating that cleavage of the bait region in α2M was the rate-determining step.

The apparent rate constant (ki,obsd) was found to be inversely related to reactant concentration. The kinetic behavior of the system was compatible with a model involving reversible, non-bait region binding of E to α2M, competitively limiting the concentration of E available for bait region cleavage. The intrinsic value of ki was (1.7±0.24) × 107 M-l s -1. Kp, the inhibitory constant associated with peripheral binding, was estimated to be in the submicromolar range.

The results of the present study point to a potential problem in interpreting kinetic data relating to protease-induced structural changes in macromolecular substrates. If there is nonproductive binding, as in the case of trypsin and α2M, and the reactions are monitored under pseudo first-order conditions ([S]0 ? [E]0), an intrinsically second-order process (such as the rate-limiting bait region cleavage in α2M) may become kinetically indistinguishable from an intrinsically first-order process (e.g. rate-limiting conformational change). Hence an excess of one component over the other should be avoided in kinetic studies addressing such systems.  相似文献   

20.
Conservation umbrellas are charismatic species, the conservation of which also conserves the high diversity of associated plants and animals. The Large Blue butterfly, Phengaris [Maculinea] arion (Lepidoptera, Lycaenidae), is a textbook example of a charismatic endangered invertebrate, intensively studied throughout Europe and protected by the EU Habitat Directive. While surveying P. arion at the westernmost outskirts of the Carpathians (Javorniky and Vsetinske Mts.), within a stronghold of the species in the Czech Republic, we asked whether occupied sites differed from unoccupied ones in the composition of vascular plants and butterfly assemblages. The occupied sites (n = 65) were small pastures, including abandoned ones, with S to W exposure, located on rugged terrain and displaying a high microtopographic heterogeneity; the unoccupied sites (n = 101) were typically mown or intensively grazed. The vegetation of occupied sites was characteristic for non-intensive submountain pasture, butterfly assemblages were species richer, contained more specialised species, and significantly higher proportion of red-listed species. P. arion thus may act as an umbrella for a high number of species associated with traditional land use in the study area and elsewhere. Its survival will depend on the continuation of small-scale land use varying in space and time, and can be threatened by uniformisation of management, even if practised under the guise of agri-environmental payments.  相似文献   

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