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1.
Various types of sequences in the human genome are known to play important roles in different aspects of genomic functioning. Among these sequences, palindromic nucleic acid sequences are one such type that have been studied in detail and found to influence a wide variety of genomic characteristics. For a nucleotide sequence to be considered as a palindrome, its complementary strand must read the same in the opposite direction. For example, both the strands i.e the strand going from 5'' to 3'' and its complementary strand from 3'' to 5'' must be complementary. A typical nucleotide palindromic sequence would be TATA (5'' to 3'') and its complimentary sequence from 3'' to 5'' would be ATAT. Thus, a new method has been developed using dynamic programming to fetch the palindromic nucleic acid sequences. The new method uses less memory and thereby it increases the overall speed and efficiency. The proposed method has been tested using the bacterial (3891 KB bases) and human chromosomal sequences (Chr-18: 74366 kb and Chr-Y: 25554 kb) and the computation time for finding the palindromic sequences is in milli seconds.  相似文献   

2.
The Brown’s Grayling (Pseudochazara amymone) is one of the most enigmatic and sought after species among European butterflies. Hiding its exact distribution for almost 40 years with the idea of protecting it, resulted in an increasing collector’s interest, with market prices reaching up to 1,000 euro for a single female after its discovery in Albania. Aiming to demystify this butterfly and enable entomologists and conservationists to see the species in its natural environment, we provide detailed information on its distribution in south-eastern Albania. In addition, we modelled the potential species distribution to facilitate further surveys within its potential range. The modelled range of P. amymone is highly fragmented stretching from the central part of eastern Albania to northern Greece and is strongly bound to ophiolite geological strata. The species was re-assessed as Endangered according to the IUCN criteria, with a predicted population decline due to construction of hydroelectric power plants in one of the locations. We argue that hiding valuable information regarding threatened insect species may have negative effects and we advocate publishing available distribution data so that conservation measures may be undertaken where and when necessary.  相似文献   

3.
The neural processing loop of language is complex but highly associated with Broca''s and Wernicke''s areas. The left dominance of these two areas was the earliest observation of brain asymmetry. It was demonstrated that the language network and its functional asymmetry during resting state were reproducible across institutions. However, the temporal reliability of resting-state language network and its functional asymmetry are still short of knowledge. In this study, we established a seed-based resting-state functional connectivity analysis of language network with seed regions located at Broca''s and Wernicke''s areas, and investigated temporal reliability of language network and its functional asymmetry. The language network was found to be temporally reliable in both short- and long-term. In the aspect of functional asymmetry, the Broca''s area was found to be left lateralized, while the Wernicke''s area is mainly right lateralized. Functional asymmetry of these two areas revealed high short- and long-term reliability as well. In addition, the impact of global signal regression (GSR) on reliability of the resting-state language network was investigated, and our results demonstrated that GSR had negligible effect on the temporal reliability of the resting-state language network. Our study provided methodology basis for future cross-culture and clinical researches of resting-state language network and suggested priority of adopting seed-based functional connectivity for its high reliability.  相似文献   

4.
5.
WHO is under pressure from all sides to justify its existence. Donors want to know what they are getting for their money, and health professionals question the relevance of the organisation''s work. The pressure to justify itself is perhaps strongest of all in Europe, where most member countries have fully fledged health infrastructures and high overall levels of health. Now there is the additional threat of encroachment into the field of public health by the European Union. The disintegration of the Soviet bloc has given WHO''s regional office in Europe a new sense of purpose and led to a major shift in resources towards the countries of central and eastern Europe. But WHO''s critics are calling for a different shift in the way its European office works: from its current concentration on broad based policy issues to the nitty-gritty of health care management and delivery.  相似文献   

6.
WHO says it has three main functions: to set normative standards; to provide technical advice and assistance on medical matters; and to advocate changes in health policy. During its 46 year history the first two functions have been a constant and uncontroversial backbone through which WHO has earned its reputation for scientific excellence. The third function, advocacy, came to the fore with the launch of Health for All in 1977, after which WHO took a key role in influencing international health policy. WHO''s friends and critics alike now say that the organisation is losing its influence and retreating into its technical and biomedical shell. This article maps the changes in WHO''s approach over the past 46 years and considers whether fears about its loss of influence are justified.  相似文献   

7.
During the 1940s, as part of its investigation of 'Communist Infiltration Into the Motion Picture Industry', the Federal Bureau of Investigation [FBI] borrowed criteria for determining if a motion picture contained communist propaganda from the Motion Picture Alliance for the Preservation of American Ideals [MPAPAI], a private, anti-communist organization located in Hollywood. An analysis of the FBI's interpretation of movies that featured black characters or explored racial themes reveals how the agency racialized its investigation of subversiveness in the early Cold War period. In the FBI's application of the MPAPAI criteria, blackness became synonymous with subversiveness and whiteness with Americanism. The FBI's racial project, as revealed in these reviews, is linked to its framing of the Communist threat and contrasted to the Truman administration's racial project and framing of the Communist threat  相似文献   

8.
The acid test of WHO''s effect on the world''s health is its impact at country level. Unless it has an impact there, all of its declarations, its debates at the World Health Assembly, its conferences, its pamphlets, its political manouvering in Geneva and the regions, all of these come to nothing. Working as it does through national governments, WHO insists that it has no role in directly managing or delivering health care. Judging WHO''s impact in individual countries is therefore difficult--its approaches are largely indirect, and initiatives may take years to bear fruit. But from the meagre resources that WHO makes available at country level it is clear why its country operations are criticised as the weakest link in an already weak chain of influence from its headquarters in Geneva to the people in its member states. Poorly funded, undertrained, and with no clear strategy to follow, its staff at country level stand little chance of making an impact.  相似文献   

9.
Nucleolar Organizer ultrastructure in Allium cepa   总被引:1,自引:0,他引:1  
The Nuoleolar Organizer Region (NOR) was studied in Allium cepa. The cells analyzed were: meristematic root tip cells, cells from the layers of the anther (exothecium, intermediate layer cells, endothecium and tapetum) and meiocytes from preleptotene to diptotene. Conventional electron microscope techniques and serial section were used in the study. Ultracytochemical tests, using preferential techniques for nucleic acids were also applied. The results show that: a) Although the NOR may have a very variable form in the different cells analyzed, in each case its fine structure is similar, being constituted of chromatin differentiated in high and low density zones. b) In each case, its cytochemical characteristics are similar; highly positively to EDTA (preferential stain for RNP) being observed in the low density zones. As scattered chromatin these would constitute the active regions of the NOR. c) In certain cases a clear relationship is seen between NOR volume and the size of the nucleolus. d) The chromatin associated to the NOR always appears as very dense zones. e) The NOR-Nucleolus relationships are established exclusively with the latter's fibrillar pars. f) The nucleolar segregation phenomenon takes place sometimes as a result of a NOR contraction and in other cases depends on the position of the NOR in relation to the nucleolus. g) In preleptotene, the NOR shows its characteristic morphology and is positive to EDTA, while from zygotene to diplotene the structure of the NOR presents no differences from the rest of the chromatin and only the lateral elements of the synaptonemal complex or its remnants are positive to EDTA. h) The synaptonemal complex runs through the NOR with no differentiation and on occasions its lateral elements show associations with the nucleolus.  相似文献   

10.
Ryk pseudokinase receptors act as important transducers of Wnt signals, particularly in the nervous system. Little is known, however, of their interactions at the cell surface. Here, we show that a Drosophila Ryk family member, DERAILED (DRL), forms cell surface homodimers and can also heterodimerize with the two other fly Ryks, DERAILED-2 and DOUGHNUT ON 2. DERAILED homodimerization levels increase significantly in the presence of its ligand, WNT5. In addition, DERAILED displays ligand-independent dimerization mediated by a motif in its transmembrane domain. Increased dimerization of DRL upon WNT5 binding or upon the replacement of DERAILED''s extracellular domain with the immunoglobulin Fc domain results in an increased recruitment of the Src family kinase SRC64B, a previously identified downstream pathway effector. Formation of the SRC64B/DERAILED complex requires SRC64B''s SH2 domain and DERAILED''s PDZ-binding motif. Mutations in DERAILED''s inactive tyrosine kinase-homologous domain also disrupt the formation of DERAILED/SRC64B complexes, indicating that its conformation is likely important in facilitating its interaction with SRC64B. Finally, we show that DERAILED''s function during embryonic axon guidance requires its Wnt-binding domain, a putative juxtamembrane extracellular tetrabasic cleavage site, and the PDZ-binding domain, indicating that DERAILED''s activation involves a complex set of events including both dimerization and proteolytic processing.  相似文献   

11.
The Committee to Study the Role of Medicine of the California Medical Education and Research Foundation (CMERF) is grateful to Dr. Watts for the following paper which served as the philosophical basis for the Committee''s study and discussions. The Committee is also grateful to CMERF and to its president, James C. Doyle, for the encouragement and cooperation it has received in the course of its intensive study of a problem which is of great interest and concern to the medical profession of California.Dr. Watts'' background paper has served as a potent stimulus in directing the Committee''s attention to the continuing dialogue between medicine and society, and in focussing on problems and issues which will be the subject of the Committee''s Second Progress Report, excerpts from which are scheduled for publication in the next issue of California Medicine.  相似文献   

12.
The guiding idea of Patricia Kitcher's Freud's Dream is that the use of interdisciplinary methodology accounts at the same time for the most central features of Freud's theory of the mind and for its most serious shortcomings. Kitcher proposes to provide an account of Freud's theory that illuminates its interdisciplinary underpinnings. While she indisputably succeeds in providing a subtle and rich reconstruction of Freud's work, her attempt to show up the limitations of interdisciplinary studies does not work. The value of her account is attributable not to the idea that Freud's was a flawed interdisciplinary endeavour but to a contextually and historically sensitive approach that makes explicit and elucidates the norms of explanation at work in his method of theory construction and that takes into account the multifaceted nature of his scientific practice.  相似文献   

13.
A theoretical framework of multiple citizenship discourses is proposed for analysing the transformation of the structure of ethnic relations in the yishuv and Israel. An historical overview indicates how Israel's 'incorporation regime' for its main ethnic and religious groups - ashkenazim, mizrachim, Orthodox-Jews, citizen and non-citizen Palestinians - was constituted through a hierarchical combination of three citizenship discourses: a collectivist republican discourse, based on the civic virtue of 'pioneering' colonization; an ethno-nationalist discourse, based on Jewish descent, and an individualist liberal discourse, based on civic criteria of membership. It is suggested that Israel's historical trajectory has consisted in its gradual transformation from a colonial to a civil society, and concomitantly in the gradual replacement of its republican citizenship discourse by a liberal discourse. Finally, the dilemmas of its ethnic and religious groups in choosing between the liberal and the ethno-nationalist citizenship discourses in the current period are charted.  相似文献   

14.
A strain of Aspergillus sp. is described and proposed as a new species under the name ‘Aspergillus insulicola sp. nov.’ Montemayor & Santiago, 1973. This strain was isolated from soil samples taken in ‘Aves Island’ during a scientific expedition. — Aves Island, situated at 15°, 40′, 42″ N and 63°, 36′, 47″ W, about 665 Km of the coast of Venezuela, has very special ecological conditions. Due to its smallness: 550 m long and 40 to 120 m across and to its low profile only 3 m over sea level, it is swept by the sea during the periodical storms and hurricanes in the area. It has thus a very interesting fauna and flora. We took a series of soil samples to study its mycological flora. Forty samples were inoculated by dilution method. In this first paper a species is described and proposed as a new species because of its macroscopic and microscopic characteristics, as well as by its biological properties, under the name ‘Aspergillus insulicola sp. nov.’. In its study we have tried to follow as closely as possible the methods recommended by Kennet B. Raper & Dorothy Fenell, world authorities on the genera Aspergillus and Penicillium. The strain is being kept in USB under the number T1, and has been sent to ATCC & CBSC to be incorporated in their collections.  相似文献   

15.
C Gray 《CMAJ》1997,156(8):1181-1183
Ottawa''s Carleton University cancelled a February blood-donor clinic after the Red Cross failed to hold sensitivity-training sessions for its volunteers. The sessions were requested after students complained that the organization''s screening procedures are insensitive and offend gay students. The Red Cross maintains that rigorous screening, including questions about high-risk sexual behaviour, is essential if the blood supply is to be protected. In March a compromise was announced: the Red Cross will begin sensitivity training for its volunteer workers in April and blood-donor clinics will return to Carleton in the fall.  相似文献   

16.
The Wnt pathway is a key regulator of development and tumorigenesis. Dpr (Dact/Frodo) influences Wnt signaling in part through the interaction of its PDZ-B domain with Dsh''s PDZ domain. Studies have shown that XDpr1a and its close relative, Frodo, are involved in multiple steps of the Wnt pathway in either inhibitory or activating roles. We found that XDpr1a is phosphorylated by casein kinase Iδ/ε (CKIδ/ε), an activator of Wnt signaling, in the presence of XDsh. Abrogating XDpr1a''s ability to bind XDsh through mutation of XDpr1a''s PDZ-B domain blocks CK1δ/ε''s phosphorylation of XDpr1a. Conversely, XDsh possessing a mutation in its PDZ domain that is unable to bind XDpr1a does not promote XDpr1a phosphorylation. Phosphorylation of XDpr1a and XDsh by CKIδ/ε decreases their interaction. Moreover, the phosphorylation of XDpr1a by CKIδ/ε not only abrogates XDpr1a''s promotion of β-catenin degradation but blocks β-catenin degradation. Our data suggest that XDpr1a phosphorylation by CKIδ/ε is dependent on the interaction of XDpr1a''s PDZ-B domain with XDsh''s PDZ domain, and that the phosphorylation state of XDpr1a determines whether it inhibits or activates Wnt signaling.  相似文献   

17.
齐宇  朱坦  高帅  王军锋  汲奕君  张墨  卜欣欣 《生态学报》2016,36(22):7335-7345
产业园区循环化改造是我国在"十二五"期间和今后一个时期内的一项重要工作,也是在园区层面实施循环发展的主要内容。物质流分析(MFA)是产业生态学的核心分析方法,正在成为资源环境管理领域有效的分析工具。通过梳理物质流分析方法的发展历程,指出产业园区循环化改造应用物质流分析存在注重物质规模而忽视环境影响、黑箱过程不利定量研究、小区域研究适用性不强以及隐藏流造成的数据误差等方面问题,同时通过大量调查实践,认为园区循环化改造可从企业开展清洁生产、促进园区内和园区间的产业共生、加强园区资源循环基础设施建设3个领域入手,在将园区全部企业分为生产性企业、再生性企业和资源循环基础设施企业3种类型基础上,提出关键流概念及其识别思路,探索构建物质流路径归类评价方法框架,归纳出8条典型物质流路径,为提升园区物质流管理水平提供方法依据,并选取天津经济技术开发区作为典型案例进行研究,最后对我国产业园区循环化改造应用物质流分析方法进行了展望。  相似文献   

18.
19.
M L Samson 《Genetics》1998,150(2):723-733
The Drosophila locus embryonic lethal abnormal visual system (elav) encodes a nuclear RNA-binding protein essential for normal neuronal differentiation and maintenance of neurons. ELAV is thought to play its role by binding to RNAs produced by other genes necessary for neuronal differentiation and consequently to affect their metabolism by an as yet unknown mechanism. ELAV structural homologues have been identified in a wide range of organisms, including humans, indicating an important conserved role for the protein. Analysis of elav germline transformants presented here shows that one copy of elav minigenes lacking a complete 3'' untranslated region (3'' UTR) rescues null mutations at elav, but that two copies are lethal. Additional in vivo experiments demonstrate that elav expression is regulated through the 3'' UTR of the gene and indicate that this level of regulation is dependent upon ELAV itself. Because ELAV is an RNA-binding protein, the simplest model to account for these findings is that ELAV binds to the 3'' UTR of its own RNA to autoregulate its expression. I discuss the implications of these results for normal elav function.  相似文献   

20.
In mycelial acetone powder of the basidiomyceteOudemansiella mucida, the presence of enzymatic systems of NADH2-oxidase and-dehydrogenase type and of NAD+-dependent alcoholdehydrogenase (using ethanol as substrate) has been detected. NADH2-oxidase has its optimal pH value in the region of 6,0 and is not too active. NADH2-dehydrogenase which reduces 2,6-dichlorophenolindophenol is very active, may be eluted from the mycelial preparation with water and its adequate pH is in the region of 6,2. On the other hand, NADH2-dehydrogenase reducing triphenyltetrazolium chloride is non-eluable with water, its activity depends on the presence of menadione and its adequate pH lies in the region of 7,4.  相似文献   

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