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91.
  1. The protection of evolutionary processes and maintenance of genetic diversity is necessary for the persistence of biodiversity and ecosystem resilience. The importance of genetic diversity has been reflected in a range of marine policy mechanisms, and the genetic ‘toolbox’ has great potential to support marine protection and marine spatial planning (MSP) at multiple scales. Despite scientific advances in the application of genetics in marine protection and management, systematic integration of genetic information has been generally lacking, primarily due to a knowledge and communication disconnect between geneticists and the marine policy and management community.
  2. To meet these outstanding needs, a ‘geospatial genetics’ approach to spatially map species-specific genetic data and associated information in a way that can be readily integrated by practitioners into marine protection and MSP decisions was developed. Techniques to derive geospatial genetic data layers, which can be viewed and mapped alongside other kinds of spatial data commonly used by conservation practitioners, hold promise for increasing the accessibility of genetic data to support policy decisions more fully.
  3. While applicable to many mobile and sessile taxa, an initial focus was placed on marine mammals, and the approach was developed and refined through a series of international meetings and published papers, as well as the development of interactive, expert-reviewed case studies hosted on the MSP tool SeaSketch.
  4. Outcomes of the work to date are currently serving in the policy arena by informing the identification of Important Marine Mammal Areas, an initiative led by the IUCN Marine Mammal Protected Areas Task Force to apply criteria to identify marine mammal habitats across the world's ocean, seas and relevant inland waters through a standardized process.
  5. It has become clear that geospatial genetics has great potential to foster increased collaboration among an intersectional community of geneticists, spatial ecologists, and practitioners. This increased opportunity for dialogue and cooperation will help ensure that evolutionary processes are factored into marine protection and MSP processes, and potentially for freshwater and terrestrial systems.
  相似文献   
92.
海岛棉与陆地棉杂种一代优势利用的研究   总被引:15,自引:0,他引:15  
1959—1962年试验证明,海陆杂种一代具有早熟、丰产、优质的特性。海陆杂种一代的籽棉产量接近陆地棉,而显著高于海岛棉。成熟期较海岛棉早,比陆地棉偏迟。生育特性一般介于两亲之间,不同程度的偏向于海岛棉,有的特性超过两亲范围以外。纤维细长,强度高,可以制成高挡纺织品。在江苏各地示范试种结果良好。在制种技术方面研究证明,采用具有某一隐性指示性状,进行不去雄杂交(人工辅助授粉),杂交率达70%,每工作日可制种6—8斤。  相似文献   
93.
户用风水光直流微电网控制策略与实现   总被引:1,自引:0,他引:1  
分布式能源、微电网和智能电网都是当前电力行业的热点课题。现有微电网研究集中在并网控制、潮流计算、建模与仿真、拓扑结构与控制等方面,实际投入运营的系统不多。该文在利用现有研究成果基础上,设计并研制了一套面向户用的微电网系统。该系统由风水光等电源、储能蓄电池、逆变器等单元构成,由微网调度器和远程SCADA系统进行监控和调度。通过系统分析、建模仿真和完善的功能设计,实现了智能调度与功率自动平衡、故障自愈和即插即用等功能,并在某农村投入试运行。研究成果对智能电网的智能能量管理和调度控制研究也具有借鉴意义。  相似文献   
94.
The nematode fauna of 369 spotted mackerel of the species Scomber australasicus, collected off the northeastern Taiwanese coast of the northwestern Pacific, was investigated monthly from April 2004 to March 2005. The following nematode species were recorded: Anisakis simplex complex, Hysterothylacium aduncum, Porrocaecum decipiens and Raphidascaris trichiuri. The seasonal variation in the infection with A. simplex third stage larva (L3) was studied throughout the 12 months. The prevalence of A. simplex L3 recorded for total fish samples was 93.6%, varying between 86.7 and 100%. There was an increase in the abundance of this nematode in spring, with the peak occurring in April. To reveal whether intrinsic factors of the spotted mackerel host contributed to infection with this nematode, fish were grouped according to their body weight, age and gonad development (reported as gonadoosomatic index, GSI), respectively, and infection parameters (i.e., prevalence, abundance and intensity) were analyzed. Results showed that abundance was significantly higher in both larger (>450 g) and older (>3 years old) fish. The gonad development of the host fish was not correlated with the intensity of the larval infection in both female and male fish. Two distinct Anisakis species were identified by PCR-RFLP, namely A. pegreffii and a recombinant genotype of A. pegreffii and A. simplex sensu stricto. These species occurred with frequencies of 97% and 3%, respectively. The usefulness of using parasites as biomarkers for spotted mackerel stock identification around Taiwanese waters was confirmed herein. A second group of 58 spotted mackerel were obtained from the coastal waters off southwestern Taiwan. In addition to the two species, A. pegreffii and the recombinant one, which were found with frequencies of 63% and 9%, respectively, an additional Anisakis species A. typica was identified with a frequency of 28% from these fish. Two spotted mackerel stocks could thus be identified based on their infrastructure of Anisakis species community and their frequency. To the best of our knowledge, this is the first report of stock identification of spotted mackerel using endoparasite biomarkers.  相似文献   
95.
The areca nut is the most widely consumed psychoactive substance in Taiwan, India, and Southeast Asia. It is considered to be an environmental risk factor for the development of oral submucous fibrosis and cancer. Arecoline, the major alkaloid of areca nut, has been known to cause cytotoxicity and genotoxicity in various systems. However, the active compound accounting for arecoline-induced damage in normal human oral cells is still uncharacterized. The present study was undertaken to identify the active metabolite of arecoline that might induce damage in human oral tissues and cause mutagenicity in Salmonella typhimurium tester strains TA 100 and TA 98. It is interesting to find that the major metabolite of arecoline, arecoline N-oxide, is moderately mutagenic to these Salmonella tester strains. This mutagenicity was potently inhibited by sulfhydryl compounds, namely, glutathione, N-acetylcysteine, and cysteine, whereas methionine is inactive in this inhibition. The mutagenicity of arecoline N-oxide was strongly inhibited by the N-oxide reducing agent titanium trichloride. The possible role of arecoline N-oxide in the induction of oral carcinogenesis by areca nut chewing is discussed.  相似文献   
96.
Epithelial to mesenchymal transition (EMT) is critical for the progression, invasion, and metastasis of epithelial tumorgenesis. Here, we provided molecular evidence associated with the antimetastatic effect of green tea polyphenol epigallocatechin-3 gallate (EGCG) in an oral squamous cell culture system by showing a nearly complete inhibition on the invasion (P < 0.001) of squamous cell carcinoma-9 (SCC-9) cells via a reduced expression of matrix metalloproteinase-2 (P < 0.001) and urokinasetype plasminogen activator (P < 0.001). EGCG exerted an inhibitory effect on cell migration (P < 0.001), motility (P < 0.001), spread, and adhesion (P < 0.001). We performed Western blot to find that EGCG inhibited p-focal adhesion kinase (p-FAK), p-Src, snail-1, and vimentin, indicating the anti-EMT effect of EGCG in oral squamous cell carcinoma. EGCG was also sufficient to inhibit phorbol-12-myristate-13-acetate-induced cell invasion and matrix metalloproteinase-9 expression, as evidenced by its inhibition on the tumor growth of SCC-9 cells in vivo via cancer cell xenografted nude mice mode. These results suggested that EGCG could reduce the invasion and cell growth of tumor cells, and such a characteristic may be of great value in developing a potential cancer therapy.  相似文献   
97.
Summary Electronmicroscope microanalyser (EMMA-4) analysis of Poria monticola colonising pine wood treated with a copper-chrome-arsenate preservative has shown that the fungus removes copper chromium and arsenic from the wood and stores these elements within the hyphae to the extent of 3–4% on a mycelial dry weight basis. The total uptake of each element varies from spot to spot examined (each 0.2 m dia.) but is on an average correlated with the concentration of the element in the impregnated wood. It appears that the rate of copper uptake is higher than of arsenic uptake.  相似文献   
98.
Nemertines are a phylum of carnivorous marine worms that possess a variety of alkaloidal, peptidic or proteinaceous toxins that serve as chemical defenses against potential predators. The hoplonemertines additionally envenomate their prey with a mixture of proboscis alkaloids delivered with the help of a calcareous stylet that punctures the skin of the victim. Anabaseine, the first of these alkaloids to be identified, stimulates a wide variety of animal nicotinic acetylcholine receptors (AChRs), especially the neuromuscular [e.g., α12β1γδ (embryogenic) or α12β1γɛ (adult)] and α7 AChRs that are inhibited by the snake peptide α-bungarotoxin. A synthetic derivative, 3-(2,4-Dimethoxybenzylidene)-Anabaseine (DMXBA; also called GTS-21), improves memory in experimental animals and humans and is currently in clinical trials to determine whether it can ameliorate cognitive problems associated with schizophrenia. Here we summarize present knowledge concerning the chemistry and mechanisms of action of these two substances (anabaseine and DMXBA) on AChRs, especially those found in the mammalian brain.  相似文献   
99.
宁南半干旱退化山区抗旱造林技术研究   总被引:3,自引:0,他引:3  
通过在年降水量仅为300~500mm地区的抗旱造林中,集成现有的新材料、新方法、新技术,提高造林成活率,为半干旱退化山区人工营造水土保持林、薪炭林、饲料林、用材林、水源涵养林等的植被恢复、改善生态环境、发挥林业可持续发展提供科技支撑。  相似文献   
100.
Farm ponds provide a home for birds and numerous species of aquatic animals in Taoyuan, Taiwan. Urbanization and development of infrastructure resulted in the gradual disappearance of these ponds. Currently, only 3800 ponds originally approximately 15.4 % remain, and 84.6 % of the surface area of the ponds has vanished. Aiming to protect avian diversity, this study used logistic regression analysis and the geostatistical approach to analyze the relationship between avian diversity and landscape structure, in an effort to elucidate the spatial driving force of avian diversity. We detected that regression-kriging (RK) was even more accurate than logistic regression (LR). In addition, the value of diversity (H′) measures may decrease instead of increase when evenness (J′) is increased. The results of this study also indicated that an exceedingly strong relationship existed among avian diversity and landscape scale, agricultural landscape indices, and pond landscape indices. The models predict that preservation of large areas of waterscapes and paddy landscapes result in greater diversity of avian species. Spatial estimation of the research area indicated that human activity substantially affected avian ecology, leading to reductions in avian diversity. Thus, the reduction of the area of ecological corridors due to urban development is expected to further reduce avian diversity in the Taoyuan region. Our approach can be used to effectively analyze the correlations between characteristics of ecosystems and the environmental landscape, to ensure that pondscapes can be appropriately maintained and ecological reserves designated to prevent further decline in avian diversity.  相似文献   
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