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1.
In the unique situation of the Korean Peninsula, which is still technically in a state of war, maritime issues are increasingly becoming critical in the relations between South Korea and North Korea. While cooperation in maritime affairs has helped to ease tensions and paved a way to reconciliatory efforts, maritime disputes adjacent to the Northern Limit Lines in the West and East Seas and maritime security issues such as South Korea's engagement in the Proliferation Security Initiative remain a source of conflict. This article looks at maritime affairs on the Korean Peninsula—a leading area of cooperation between the South and the North as well as a potential conflict flash point.  相似文献   

2.
This article examines the 2008 Sino-Japanese Consensus on the East China Sea in the context of the seemingly vague obligations in the Law of the Sea Convention regarding overlapping claims for states to “make every effort to enter into provisional arrangements of a practical nature.” The conclusion reached is that, while the claims of the two states in the East China Sea are based in good faith, there is a lack of reciprocity in the Consensus that helps explain it's fragile nature.  相似文献   

3.
Futility is not a purely medical concept. Its subjective nature requires a balanced procedural approach where competing views can be aired and in which disputes can be resolved with procedural fairness. Law should play an important role in this process. Pure medical models of futility are based on a false claim of medical sovereignty. Procedural approaches avoid the problems of such claims. This paper examines the arguments for and against the adoption of a procedural approach to futility determination.  相似文献   

4.
In this study the depth of the atmospheric boundary layer (ABL) over the Tibetan Plateau was measured during a regional radiosonde observation campaign in 2008 and found to be deeper than indicated by previously measurements. Results indicate that during fair weather conditions on winter days, the top of the mixed layers can be up to 5 km above the ground (9.4 km above sea level). Measurements also show that the depth of the ABL is quite distinct for three different periods (winter, monsoon-onset, and monsoon seasons). Turbulence at the top of a deep mixing layer can rise up to the upper troposphere. As a consequence, as confirmed by trajectory analysis, interaction occurs between deep ABLs and the low tropopause during winter over the Tibetan Plateau.  相似文献   

5.
6.
A nationwide survey was performed to know the distribution and prevalence of human Gymnophalloides seoi infection on western and southern coastal islands in the Republic of Korea. A total of 4,178 fecal specimens were collected from residents on 45 (24 western and 21 southern) islands, and examined by Kato-Katz and formalin-ether sedimentation techniques. Eggs of G. seoi were detected from 160 (3.8%) people living on 22 (13 western and 9 southern) islands. The prevalence varied by the location of islands; higher on western islands than on southern islands. The highest prevalence was found on Amtaedo (25.3%), followed by Cheungdo (25.0%), and Anchwado (20.9%) (Shinan-gun). A little lower prevalence was observed on Munyodo (13.3%), Shinshido (12.9%), and Sonyudo (10.3%) (Kunsan-shi). Of the remaining islands, the regions showing the prevalence greater than 5% included Kohado, Dallido (Mokpo-shi), Pyeongildo, Kogumdo (Wando-gun), and Keogumdo (Kohung-gun). A strong age predilection was noted (p < 0.05); 95% of the infected people were over 40 years old. Females showed a little higher prevalence than males. The results indicate that human G. seoi infection is more widely distributed than previously considered. Nine of 11 islands (excluding the 2 known areas Munyodo and Sunyudo) that showed greater prevalence than 5% are regarded as new endemic foci of G. seoi.  相似文献   

7.
分析了纤维蛋白胶存在的问题,如蛋白胶不同供体来源、成份来源、应用的简易性与有效性、止血功效局限、机械强度与纤溶抑制剂的选择等,并提出相应的解决方案。  相似文献   

8.
The phase change for an amylose solution in the binary solvent system of dimethylsulfoxide (DMSO) with water was investigated under various conditions from sol to gel. The phase change was determined with measurements of the fluorescent depolarization and other methods by varying the solvent constitution at 25°C, and then varying the temperature at 10% of DMSO concentration.

The phase diagrams obtained with both variables were substantially similar and were also similar to those for an aqueous agarose solution. This similarity in phase diagram suggests a similar gel formation mechanism of amylose to agarose.

It was found that the phase separation point for the amylose solution agreed with the gel formation point and also with the starting point of retrogradation.  相似文献   

9.
Kurt Michael Shusterich, Resource Management and the Oceans: The Political Economy of Deep Seabed Mining (Boulder, Colorado: Westview Press, 1982), 344 pp.

Manjula R. Shyam, Metals from the Seabed: Prospects for Mining Polymetallic Nodules by India (New Delhi: Oxford and IBH Publishing Co., 1982), 165 pp.  相似文献   

10.
InhibitionofAcrosomalEnzymesbyGossypolIsRelatedtoItsAntifertilityActionYUANYu-ying;(袁玉英)ZHANGYan-lin;(张燕林)SHIQi-xian(石其贤)(Zhe...  相似文献   

11.
在中国石蕊属种类的研究中,依据形态特征及nrD NA ITS序列数据,鉴定出采自海南的一新记录种——粗糙石蕊(Cladonia rudis)。提供了描述及图片,依据序列数据估计了其与近缘谱系的分化时间。  相似文献   

12.
DNA甲基化是表观遗传修饰的重要形式之一,是植物中较早发现的DNA共价修饰方式。在植物的正常生长发育中,DNA甲基化与植物基因组维持、体细胞无性系变异、外来基因防御、内源基因的表达、转基因沉默以及基因印迹之间有着极大的关系,因此,植物DNA甲基化的研究对植物基因工程的发展有着举足轻重的作用。本文介绍了参与DNA甲基化的各种酶和蛋白质,阐述了DNA甲基化相关机制的最新研究进展。  相似文献   

13.
Pno1 is a protein that plays a role in proteasome and ribosome neogenesis in yeast. So far, its functions in mammalian cells have not been investigated. To understand its function in mammals, we performed in situ hybridization analysis of Pno1 expression in different development stages and generated Pno1 gene knockout (KO) and transgenic (Tg) mice lineages. The results showed early lethality of homozygous Pno1 KO lineage caused, as demonstrated in parallel by ex vivo experiments, by arrest of embryo development before compaction stage. Though, heterozygous (HET) mice with 50% of normal Pno1 mRNA concentration were fertile and showed no obvious anomalies. The lymphoid organs of HET mice were normal in size, weight and cellularity, with normal T and B cell subpopulations. TCR-triggered activation and proliferation of HET T cells were normal. Proteasome activities in HET organs were uncompromised. Tg mice with actin promoter-driven Pno1 expression were also fertile, with no apparent anomalies, although they expressed 2–5-fold higher Pno1 mRNA levels. The lymphoid organs of Tg mice were of normal size, weight and cellularity with normal T and B cell sub-populations. TCR-triggered activation and proliferation of Tg T cells were normal. Tg organs and tissues presented normal proteasome activity as did their wild type counterparts. Tagged Pno1 over-expression in L cells and density gradient fractionation established that Pno1 existed in large complexes with sedimentation rates between 20S and 26S, bigger than mature 26S proteasomes. Pno1 in fractions did not coincide with 40S or 60S ribosome subunits. Our study indicates that Pno1 is essential for cellular functions, but only a small percentage of its normal level is sufficient, and excessive amounts are neither harmful nor useful. The nature of the large complexes it associates with remains to be identified, but it is certain that they are not mature proteasomes or ribosomes.  相似文献   

14.
To determine the status of Enterobius vermicularis infection among children living on western and southern coastal islands of the Republic of Korea, children (3-10 years) in 39 kindergartens and primary schools were examined using the cello-tape anal swab method, during July and August 2000. Of 1,661 children examined, 307 (18.5%) were found to be positive for E. vermicularis eggs. The highest infection rate (59.3%) was found in a kindergarten and a branch school of Shinyang primary school on Chujado, Jeju-do (Province). Remarkable differences in egg positive rates were observed in different localities. The egg positive rate for boys (21.3%) was significantly higher than that of girls (15.4%) (P = 0.02). However, positive rates were not significantly dependent on age. The results of the present study show that E. vermicularis infection is highly prevalent among pre-school and primary school children living on the western and southern coastal islands of the Republic of Korea, and indicate the need for efforts to control this infection.  相似文献   

15.
Cathepsin D (CD) plays an important role in both biological and pathological processes, although the cleavage characteristics and substrate selection of CD have yet to be fully explored. We employed liquid chromatography-tandem mass spectrometry (LC-MS/MS) to identify the CD cleavage sites in bovine serum albumin (BSA). We found that the hydrophobic residues at P1 were not only a preferential factor for CD cleavage but that the hydrophobicity at P1’ also contributed to CD recognition. The concept of hydrophobic scores of neighbors (HSN) was proposed to describe the hydrophobic microenvironment of CD recognition sites. The survey of CD cleavage characteristics in several proteins suggested that the HSN was a sensitive indicator for judging the favorable sites in peptides for CD cleavage, with HSN values of 0.5–1.0 representing a likely threshold. Ovalbumin (OVA), a protein resistant to CD cleavage in its native state, was easily cleaved by CD after denaturation, and the features of the cleaved peptides were quite similar to those found in BSA, where a higher HSN value indicated greater cleavability. We further conducted two-dimensional gel electrophoresis (2DE) to find more proteins that were insensitive to CD cleavage in CD-knockdown cells. Based on an analysis of secondary and three-dimensional structures, we postulated that intact proteins with a structure consisting of all α-helices would be relatively accessible to CD cleavage.  相似文献   

16.
Chlorine dioxide gas and vaporous hydrogen peroxide sterilant have been used in the cleanup of building interiors contaminated with spores of Bacillus anthracis. A systematic study, in collaboration with the U.S. Environmental Protection Agency, was jointly undertaken by the U.S. Army-Edgewood Chemical Biological Center to determine the sporicidal efficacies of these two fumigants on six building structural materials: carpet, ceiling tile, unpainted cinder block, painted I-beam steel, painted wallboard, and unpainted pinewood. Critical issues related to high-throughput sample processing and spore recovery from porous and nonporous surfaces included (i) the extraction of spores from complex building materials, (ii) the effects of titer challenge levels on fumigant efficacy, and (iii) the impact of bioburden inclusion on spore recovery from surfaces and spore inactivation. Small pieces (1.3 by 1.3 cm of carpet, ceiling tile, wallboard, I-beam steel, and pinewood and 2.5 by 1.3 cm for cinder block) of the materials were inoculated with an aliquot of 50 μl containing the target number (1 × 106, 1 × 107, or 1 × 108) of avirulent spores of B. anthracis NNR1Δ1. The aliquot was dried overnight in a biosafety cabinet, and the spores were extracted by a combination of a 10-min sonication and a 2-min vortexing using 0.5% buffered peptone water as the recovery medium. No statistically significant drop in the kill efficacies of the fumigants was observed when the spore challenge level was increased from 6 log units to 8 log units, even though a general trend toward inhibition of fumigant efficacy was evident. The organic burden (0 to 5%) in the spore inoculum resulted in a statistically significant drop in spore recovery (at the 2 or 5% level). The effect on spore killing was a function of the organic bioburden amount and the material type. In summary, a high-throughput quantitative method was developed for determining the efficacies of fumigants, and the spore recoveries from five porous materials and one nonporous material ranged between 20 and 80%.Biological terrorism has become a major concern in the United States since the anthrax spore-tainted letters in the fall of 2001 resulted in contamination and closure of the U.S. Postal Service Curseen-Morris Processing and Distribution Center (Brentwood Post Office), the Hart Senate Office Building, and the American Media Inc. office building in Boca Raton, FL. The contamination of infrastructure posed an unprecedented challenge of decontaminating over 20,000,000 cubic feet (∼1 million sq. ft.) of combined building interior space (6). The incident required concerted action from the government of the United States and the private sector to develop technologies for building interior cleanup. A number of liquid (29) and gaseous (3) products were granted crisis exemptions under the Federal Insecticide, Fungicide, and Rodenticide Act by the U.S. Environmental Protection Agency (EPA) for use as sterilants against Bacillus anthracis spores, but their application and efficacy in the context of large three-dimensional spaces and complex building material surfaces were not fully understood. No products were (or currently are) registered for use in such applications, involving large volumes and complex (porous and nonporous) structural building materials.In early 2005, a systematic study of laboratory-scale decontamination of five porous surfaces (carpet, ceiling tile, cinder block, painted wallboard, and unpainted wood) and one nonporous surface (painted I-beam steel) was initiated by the U.S. EPA in collaboration with the U.S. Army Edgewood Chemical Biological Center (ECBC). The overall objective of this collaborative study was to systematically investigate the abilities of fumigants to effectively decontaminate building materials contaminated with anthrax spores. This unprecedented systematic investigation involved the determination of efficacy (or log reduction in the number of viable spores) as a function of fumigant technology, technology operating parameters (e.g., fumigant concentration and exposure time), environmental conditions (temperature and relative humidity [RH]), and building material types. The magnitude and scope of this study required that new methods be developed to incorporate the use of complex materials in sporicidal efficacy testing and the processing of an unprecedented number of complex samples.Current standardized sporicidal test methods include the Association of Official Analytical Chemists (AOAC International) sporicidal activity of disinfectant test (AOAC Official Method 966.04) (4) and the American Society for Testing and Materials (ASTM) 2414-05 (3) and quantitative carrier test (QCT) (2). All of these methods are based on testing hard-surface carrier-based spores, which are submerged in a disinfectant for a desired contact time, followed by the addition of a neutralizer and enumeration of viable spores recovered from the carrier. Almost all standard test methods for liquid disinfectants use small coupons, e.g., 5- by 5-mm squares or 1-cm discs, on which 1 million to 10 million (6 to 7 log) spores are inoculated. While AOAC Official Method 966.04 is qualitative, the other two test methods are quantitative and provide log reduction estimates. Currently, demonstration of a >6-log-unit inactivation of B. anthracis or an appropriate surrogate spore (e.g., Bacillus subtilis) using a quantitative test method, such as QCT, which is also known as ASTM 2197-02, or the three-step method (TSM), also known as ASTM 2414-05, by a decontaminant is a requirement for product registration as a sporicidal agent against spores of B. anthracis Ames (18).Key information on three critical issues was lacking at the start of this study. First, optimal spore extraction protocols that could be scaled to process over 200 samples per run (or day) were lacking. Second, the appropriate spore challenge level for fumigation studies was unknown, even though a range between 5 and 8 log spores/coupon has been used in a number of recent disinfection studies (12, 13, 14, 16, and 17). Finally, it was not known if protein serum (an organic burden is included in standard procedures, such as AOAC Official Method 966.04) should be included in the testing performed with the fumigants. The specific objectives of this study, therefore, were to (i) develop scalable coupon-processing/spore extraction protocols from six building materials that would result in recovery of >20% of the spores inoculated per coupon, (ii) investigate the effects of three spore challenge levels on spore extraction and the efficacy of chlorine dioxide (CD) gas and vaporous hydrogen peroxide (VHP), and, finally, (iii) investigate the effect of organic burden inclusion on spore recovery and sterilization using CD gas.  相似文献   

17.
18.
SARS病毒及相关冠状病毒的生物学特征   总被引:7,自引:0,他引:7  
重症急性呼吸综合征 (severeacuterespiratorysyndrome ,SARS) ,临床表现为非典型肺炎。2 0 0 2年底我国广东发现此种当时不明病因的疾病 ,此后在越南、中国香港、加拿大、美国等三十多个国家和地区也相继发现类似病例。由于SARS具有很高的传染性 ,死亡率也高 ,各国和世界卫生组织 (WHO)对此病高度重视。WHO迅速建立起由全球 10个国家的 13个实验室组成的协作研究和监测网络。一种新型的冠状病毒 (coronavirus)被认为极可能是SARS的病原体 ,因为它满足了 6个科赫要点 (Koch’spostulates)。2 0 0 3年 4月 12日 ,加拿大科学家首次公布了SARS病毒Tor2的基因组序列。4月 16日 ,WHO正式确认SARS病毒是SARS的病原体。目前我国SARS的病情仍然十分严峻 ,现就SARS病毒及相关冠状病毒的生物学特征和可能的药物防治靶点作一综述。  相似文献   

19.
20.
李莉  慕晓玲 《生物磁学》2009,(20):3990-3993
砷在自然界分布广泛,主要以砷化物的形式存在,具有较强毒性。可通过多种途径进入人类的生活环境引起健康危害,砷代谢过程涉及到复杂的酶促或非酶促反应过程,近年来以砷代谢为突破口的砷中毒发病机制探索成为新的研究热点,本文就有关砷在生物体内代谢方面的研究做一综述,以期有助于慢性砷中毒作用机制的研究。  相似文献   

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