983 resultados para Milton, John, 1608-1674. Paradise lost.


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For complex disease genetics research in human populations, remarkable progress has been made in recent times with the publication of a number of genome-wide association scans (GWAS) and subsequent statistical replications. These studies have identified new genes and pathways implicated in disease, many of which were not known before. Given these early successes, more GWAS are being conducted and planned, both for disease and quantitative phenotypes. Many researchers and clinicians have DNA samples available on collections of families, including both cases and controls. Twin registries around the world have facilitated the collection of large numbers of families, with DNA and multiple quantitative phenotypes collected on twin pairs and their relatives. In the design of a new GWAS with a fixed budget for the number of chips, the question arises whether to include or exclude related individuals. It is commonly believed to be preferable to use unrelated individuals in the first stage of a GWAS because relatives are 'over-matched' for genotypes. In this study, we quantify that for GWAS of a quantitative phenotype, relative to a sample of unrelated individuals surprisingly little power is lost when using relatives. The advantages of using relatives are manifold, including the ability to perform more quality control, the choice to perform within-family tests of association that are robust to population stratification, and the ability to perform joint linkage and association analysis. Therefore, the advantages of using relatives in GWAS for quantitative traits may well outweigh the small disadvantage in terms of statistical power.

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Effective and targeted conservation action requires detailed information about species, their distribution, systematics and ecology as well as the distribution of threat processes which affect them. Knowledge of reptilian diversity remains surprisingly disparate, and innovative means of gaining rapid insight into the status of reptiles are needed in order to highlight urgent conservation cases and inform environmental policy with appropriate biodiversity information in a timely manner. We present the first ever global analysis of extinction risk in reptiles, based on a random representative sample of 1500 species (16% of all currently known species). To our knowledge, our results provide the first analysis of the global conservation status and distribution patterns of reptiles and the threats affecting them, highlighting conservation priorities and knowledge gaps which need to be addressed urgently to ensure the continued survival of the world’s reptiles. Nearly one in five reptilian species are threatened with extinction, with another one in five species classed as Data Deficient. The proportion of threatened reptile species is highest in freshwater environments, tropical regions and on oceanic islands, while data deficiency was highest in tropical areas, such as Central Africa and Southeast Asia, and among fossorial reptiles. Our results emphasise the need for research attention to be focussed on tropical areas which are experiencing the most dramatic rates of habitat loss, on fossorial reptiles for which there is a chronic lack of data, and on certain taxa such as snakes for which extinction risk may currently be underestimated due to lack of population information. Conservation actions specifically need to mitigate the effects of human-induced habitat loss and harvesting, which are the predominant threats to reptiles.

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The present study focuses on the translational strategies of Cocksfoot mottle virus (CfMV, genus Sobemovirus), which infects monocotyledonous plants. CfMV RNA lacks the 5'cap and the 3'poly(A) tail that ensure efficient translation of cellular messenger RNAs (mRNAs). Instead, CfMV RNA is covalently linked to a viral protein VPg (viral protein, genome-linked). This indicates that the viral untranslated regions (UTRs) must functionally compensate for the lack of the cap and poly(A) tail. We examined the efficacy of translation initiation in CfMV by comparing it to well-studied viral translational enhancers. Although insertion of the CfMV 5'UTR (CfMVe) into plant expression vectors improved gene expression in barley more than the other translational enhancers examined, studies at the RNA level showed that CfMVe alone or in combination with the CfMV 3'UTR did not provide the RNAs translational advantage. Mutation analysis revealed that translation initiation from CfMVe involved scanning. Interestingly, CfMVe also promoted translation initiation from an intercistronic position of dicistronic mRNAs in vitro. Furthermore, internal initiation occurred with similar efficacy in translation lysates that had reduced concentrations of eukaryotic initiation factor (eIF) 4E, suggesting that initiation was independent of the eIF4E. In contrast, reduced translation in the eIF4G-depleted lysates indicated that translation from internally positioned CfMVe was eIF4G-dependent. After successful translation initiation, leaky scanning brings the ribosomes to the second open reading frame (ORF). The CfMV polyprotein is produced from this and the following overlapping ORF via programmed -1 ribosomal frameshift (-1 PRF). Two signals in the mRNA at the beginning of the overlap program approximately every fifth ribosome to slip one nucleotide backwards and continue translation in the new -1 frame. This leads to the production of C-terminally extended polyprotein, which encodes the viral RNA-dependent RNA polymerase (RdRp). The -1 PRF event in CfMV was very efficient, even though it was programmed by a simple stem-loop structure instead of a pseudoknot, which is usually required for high -1 PRF frequencies. Interestingly, regions surrounding the -1 PRF signals improved the -1 PRF frequencies. Viral protein P27 inhibited the -1 PRF event in vivo, putatively by binding to the -1 PRF site. This suggested that P27 could regulate the occurrence of -1 PRF. Initiation of viral replication requires that viral proteins are released from the polyprotein. This is catalyzed by viral serine protease, which is also encoded from the polyprotein. N-terminal amino acid sequencing of CfMV VPg revealed that the junction of the protease and VPg was cleaved between glutamate (E) and asparagine (N) residues. This suggested that the processing sites used in CfMV differ from the glutamate and serine (S) or threonine (T) sites utilized in other sobemoviruses. However, further analysis revealed that the E/S and E/T sites may be used to cleave out some of the CfMV proteins.

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The ocellated angelshark, Squatina tergocellatoides, Chen, 1963 is redescribed from the holotype, which was thought to be lost. Its recent recovery has allowed for a revised description, including new data, and comparison to other Western Pacific squatinids. Squatina tergocellatoides can be distinguished from its congeners by three pairs of prominent large black spots, each with a diameter greater than eye length; two on each pectoral fin at anterior and posterior angles and one on each side near the tail base; another three pairs of lesser defined spots, one large spot on base of each dorsal fin and one located laterally on each side of tail located below first dorsal fin. Ventral surface is uniformly white to cream coloured, and margins of pectoral fins and tail similar in colour to dorsal side. Pectoral fins with angular lateral apices and rounded posterior lobe, pelvic fin tips not reaching origin of first dorsal fin, strongly fringed nasal barbels, small inter-orbital space, head and mouth lengths, broad internarial width and pelvic fin base, a very small pelvic girdle width, and a caudal fin with triangular ventral lobe greater in length than dorsal lobe. Comments on additional specimens are provided, as well as observations on biogeography. A review of western Pacific squatinids is also provided.

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Contains correspondence, memoranda, speeches, etc. to various departments on the National Jewish Welfare Board, the Anti-Defamation League, and the Jewish War Veterans of the U.S. relating to Jewish personnel in the U.S. Armed Forces during World War II and concerned with public relations, anti-Semitism and discrimination, the chaplaincy, etc.; includes also published articles and radio addresses for the same period and extensive correspondence with Rabbi Milton Steinberg from 1946 to 1950, as well as material by and about Rabbi Steinberg. The collection also contains personal family correspondence while Weill was serving overseas during World War I, memorabilia and a scrapbook relating to these military experiences, and undated typescript copies of dramatic sketches.

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Digital image

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Digital image

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Tutkielmassa esitellään ja arvioidaan John Searlen teoriaa tietoisuudesta. Tietoisuus (consciousness) on Searlen mukaan tärkein mielenfilosofinen käsite. Searle ei määrittele käsitettä tarkasti, vaan tyytyy esittämään sitä kuvaavia esimerkkejä ja analogioita. Tietoisuuden keskeisimmiksi ominaisuuksiksi Searlen teoriassa näyttävät muodostuvan intentionaalisuus (intentionality), subjektiivisuus (subjectivity) ja kausaalinen vaikutus käyttäytymiseen (mental causation). Näihin ominaisuuksiin liittyvät myös Searlen painavimmat tietoisuudesta esittämät argumentit. Argumenttien analysointi on tutkielman tärkein tavoite. Searlen yhteysperiaatteen (Connection Principle) mukaan intentionaalisia tiloja voi olla vain olennolla, jolla voi olla tietoisia intentionaalisia tiloja, ja jokainen alitajuinen intentionaalinen tila on ainakin potentiaalisesti tietoinen. Toisin sanoen intentionaalisuuden ja tietoisuuden välillä vallitsee välttämätön yhteys seuraavasti: on loogisesti välttämätöntä, että jokainen intentionaalinen tila voi ainakin periaattessa päästä tietoisuuteen.Tutkielmassa kuitenkin osoitetaan, että yhteysperiaateeseen on syytä suhtautua epäillen. Searlen yhteysperiaatteen puolesta esittämä argumentti näyttää nimittäin sisältävän dilemman. Jos erottelu intrinsiseen ja näennäiseen intentionaalisuuteen tulkitaan Searlen tavoin, syyllistytään sen olettamiseen, mikä pitäisi todistaa; jos taas erottelu tulkitaan toisin kuin Searle, argumentti ei tue yhteysperiaatetta. Searlen mukaan mentaaliset tilat ovat aina jonkun mentaalisia tiloja. Tästä väitteestä Searle pyrkii johtamaan toisen, paljon radikaalimman väitteen: mielen ilmiöt kuuluvat omaan ontologiseen kategoriaansa, subjektiivisten mentaalisten tilojen kategoriaan. Searlen käsitystä tukee Thomas Nagelin esittämä, hyvin samansisältöinen argumentti. Yksimielisyys ei kuitenkaan ole erehtymättömyyden tae, sillä Paul Churchlandin kritiikki näyttää pahasti horjuttavan Searlen subjektiivisuusargumentin uskottavuutta. Churchland väittää Searlen syyllistyvän intensionaaliseen virhepäätelmään. Yksittäisen henkilön episteemisen pääsyn rajoittuneisuudesta ei Churchlandin mukaan voida tehdä mitään ontologisia johtopäätöksiä, koska tiedetyksi tuleminen ei ole objektin aito ominaisuus. Vastaväite näyttää olevan kohtalokas Searlen subjektiivisuusargumentille. Subjektiivisuuden ongelma näyttää olevan perustava metafyysinen vedenjakaja, joka jakaa mielenfilosofiset teoriat toisaalta materialistisiin, toisaalta dualistisiin. Searle uskoo, että mieli-ruumis -ongelma (mind-body problem) on ratkaistavissa ilman, että tarvitsee valita kumpaakaan. Ratkaisu sisältyy kahteen Searlen näennäisesti yhteensopimattomaan teesiin. Ensimmäisen teesin mukaan mentaaliset tilat ovat todellisia ilmiöitä, eikä niitä voida redusoida mihinkään muuhun tai eliminoida määrittelemällä ne uudestaan. Toisen teesin mukaan aivojen operaatiot aiheuttavat mentaaliset tilat ja mentaaliset tilat ovat aivojen piirteitä. Teeseistä jälkimmäinen osoittautuu ongelmalliseksi syistä, jotka Jaegwon Kim on esittänyt. Jos mentaaliset tilat olisivat aivojen ominaisuuksia, ei mielen ja aivojen välinen suhde voisi olla kausaalinen, koska kausaatiossa (causation) on aina kyse kahden erillisen entiteetin tai tapahtuman välisestä relaatiosta, jossa suhteen osapuolien välillä on oltava ajallista etäisyyttä. Toiseksi Searlen vertaus tietoisuuden ja aivojen suhteesta kappaleen kiinteyden ja sen mikrorakenteen suhteeseen epäonnistuu, koska tietoisuus ja kiinteys kuuluvat Searlen teoriassa eri ontologisiin kategorioihin, eikä niitä siten voi ongelmattomasti rinnastaa. Searlen analogia kiinteyteen murtuu myös siksi, että kappaleen mikrorakenne ei yksinkertaisesti aiheuta sen kiinteyttä. Tietoisuus ei siis voi olla samanaikaisesti aivojen ominaisuus ja aivojen kausaalisen toiminnan seuraus. Tutkielmassa päädytään puolustamaan kantaa, että Searlen argumentit eivät ole vakuuttavia ja että Searle ei ole onnistunut eksplikoimaan teoriaa, joka välttäisi dualismiin ja materialismiin liittyvät tunnetut ongelmat. Kysymys mikä on mielen suhde ruumiiseen, jää siten avoimeksi. Avainsanat: intentionaalisuus, mentaalinen, mieli-ruumis -ongelma, Searle, subjektiivisuus, tietoisuus

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'Untitled (after Steven and John)' takes inspiration from Spielbergian tracking shots and Baldessarian collages to create ghostly apparitions that explore the affective power of the cinematic close up. By appropriating and obfuscating this common filmic convention, the work investigates the intersubjective potential of the moving image.

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Political communication scholars, journalists, and political actors alike, argue that the political process, and deliberative democracy (democracy founded on informed discussion inclusive of citizens), have lost their rational authenticity in that image and media spectacle have become more central to public opinion formation and electoral outcomes than policy. This entry examines the validity of that perception, and the extent to which “image” has emerged as a more significant factor in the political process. And if image is so important in political culture, what the impacts might be on the functioning of democratic processes.

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Acyl carrier protein is an integral component of many cellular metabolic processes. A number of studies have reported self-acylation behavior in acyl carrier proteins. Although AM exhibit high levels of similarity in their primary and tertiary structures, self-acylation behavior is restricted to only some ACPs that can be classified into two major families based on their function. The first family of ACPs is involved in polyketide biosynthesis, whereas the second family participates in fatty acid synthesis. Facilitated by the growing number of genome sequences available for analyses, large-scale phylogenetic studies were used in these studies to uncover as to how self-acylation behavior of acyl carrier proteins is linked with the evolution of metabolic pathways in organisms. These studies show that self-acylation behavior in acyl carrier proteins was lost during the course of evolution, with certain organisms and organelles viz. plastids, retaining it for specified functions. (C) 2009 IUBMB IUBMB Life, 61(8): 853-859, 2009

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If smart cities run on big data and algorithms that channel only 'relevant' information and opinions to us, how do we maintain the diversity of ideas and possibilities that drives truly smart cities?

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Within the history of twentieth-century design, there are a number of well-known objects and stories that are invoked time and time again to capture a pivotal moment or summarize a much broader historical transition. For example, Marcel Breuer’s Model B3 chair is frequently used as a stand-in for the radical investigations of form and new industrial materials occurring at the Bauhaus in the mid-1920s. Similarly, Raymond Loewy’s streamlined pencil sharpener has become historical shorthand for the emergence of modern industrial design in the 1930s. And any discussion of the development of American postwar “organic design” seems incomplete without reference to Charles and Ray Eames’s molded plywood leg splint of 1942. Such objects and narratives are dear to historians of modern design. They are tangible, photogenic subjects that slot nicely into exhibitions, historical surveys, and coffee-table best sellers...