994 resultados para Maupeou, René-Nicolas-Charles-Augustin de, 1714-1792.


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Background: There is growing evidence that microglia are key players in the pathological process of amyotrophic lateral sclerosis (ALS). It is suggested that microglia have a dual role in motoneurone degeneration through the release of both neuroprotective and neurotoxic factors. Results: To identify candidate genes that may be involved in ALS pathology we have analysed at early symptomatic age (P90), the molecular signature of microglia from the lumbar region of the spinal cord of hSOD1(G93A) mice, the most widely used animal model of ALS. We first identified unique hSOD1(G93A) microglia transcriptomic profile that, in addition to more classical processes such as chemotaxis and immune response, pointed toward the potential involvement of the tumour suppressor gene breast cancer susceptibility gene 1 (Brca1). Secondly, comparison with our previous data on hSOD1(G93A) motoneurone gene profile substantiated the putative contribution of Brca1 in ALS. Finally, we established that Brca1 protein is specifically expressed in human spinal microglia and is up-regulated in ALS patients. Conclusions: Overall, our data provide new insights into the pathogenic concept of a non-cell-autonomous disease and the involvement of microglia in ALS. Importantly, the identification of Brca1 as a novel microglial marker and as possible contributor in both human and animal model of ALS may represent a valid therapeutic target. Moreover, our data points toward novel research strategies such as investigating the role of oncogenic proteins in neurodegenerative diseases.

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The population biology and status of the painted sweeplips (Diagramma pictum) and spangled emperor (Lethrinus nebulosus) in the southern Arabian Gulf were established by using a combination of size-frequency, biological, and size-at-age data. Transverse sections of sagittal otoliths were characterized by alternating translucent and opaque bands that were validated as annuli. Comparisons of growth characteristics showed that there were no significant differences (P>0.05) between sexes. There were well defined peaks in the reproductive cycle, spawning occurred from April to May for both species, and the mean size at which females attained sexual maturity was 31.8 cm fork length (LF) for D. pictum and 27.6 cm (LF) for L. nebulosus. The mean sizes at first capture (21.1 cm LF for D. pictum and 26.4 cm LF for L. nebulosus) were smaller than the sizes for both at first sexual maturity and those at which yield per recruit would be maximized. The range of fishing-induced mortality rates for D. pictum (0.37−0.62/yr) was substantially greater than the target (Fopt=0.07/yr) and limit (Flimit=0.09/ yr) estimates. The range of fishing-induced mortality rates for L. nebulosus (0.15/yr to 0.57/yr) was also in excess of biological reference points (Fopt=0.10/yr and Flimit=0.13/yr). In addition to growth overfishing, the stocks were considered to be recruitment overfished because the biomass per recruit was less than 20% of the unexploited levels for both species. The results of the study are important to fisheries management authorities in the region because they indicate that both a reduction in fishing effort and mesh-size regulations are required for the demersal trap fishery.

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Ang 1-7-ak duen eragina giza espermatozoideen mugikortasunean aztertu dugu, baita molekula honek Akt-ren fosforilazioan dituen efektuak ere. Bestalde, Mas hartzailearen presentzia espermatozoideetan ikertu dugu.

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[EUS] Proiektu honen helburua esterasaren lorpena aztertzeaz gain, lorpenerako erabilitako Pseudomona putida mikroorganismoaren hartzidura aztertzea da, ondoren mikroorganismo horri dagokion parametro zinetikoak lortzeko eta erreaktore baten diseinua egin ahal izateko. Horrekin batera, hartziduran eragin dezaketen faktoreak aztertuko dira (tenperatura, aparra, aireztapena, pH …) kontrol eta monitoriazioan kontutan izateko. Horrez guztiaz gain eta prozesua erreaktorean aztertzeaz gain, matrazeetan ere aztertu da, ondoren bi sistemetako hazkuntzak konparatzeko eta aztertzeko helburuarekin. Hartzidura prozesuaren ostean, esterasa proteina lorpena mintzen bidezko prozesuetan oinarrituko da. Proiektu honetan mintzak duten eraginkortasuna kalkulatuko da, baita lortutako emaitzen inguruko hausnarketa bat egin ere.

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The gut contents of Sardina pilchardus specimens captured in Izmir Bay were examined in order to determine their feeding regimes. Of the 365 stomachs examined, 321 (87.95%) contained food and 44 (12.05%) were empty. Analysis of gut contents verified that S. pilchardus feeds on zooplankton. The most important group in the diet of S. pilchardus was copepods (79.79%). Decapod crustacean larvae (8.17%) and bivalves (3.18%) were second and third, respectively, in order of importance. The application of analysis of variance to monthly data of numerical percentage, weight percentage, frequency of occurrence and index of relative importance indicated that there was no significant difference between months. Oncaea media was the most dominant species for six months of the year. Euterpina acutifrons, Centropages typicus, Calanoida, Oncaea sp. and Corycaeus sp. were the most dominant for March, April, May, September, October and December.

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O objetivo da tese de doutorado consistirá na defesa de uma alternativa para os dilemas políticos concernentes à incomparabilidade no interior de uma comunidade específica ou entre comunidades distintas, presente nas discussões em torno do pluralismo contemporâneo. Esta via é inspirada nos conceitos de bens constitutivos, avaliações fortes e articulação, desenvolvidos pelo filósofo canadense Charles Taylor, e é também uma tentativa de se pensar acerca de um projeto de crítica política que leve em consideração a motivação como elemento incontornável para a filosofia prática. A incomparabilidade, isto é, impossibilidade de critérios no julgamento entre práticas específicas, mas com repercussões públicas, levanta a questão de até que ponto é possível avaliar e deliberar racionalmente sobre modos de vida distintos e, às vezes, auto-excludentes. Tal problemática pode ser vista fortemente no chamado debate liberal-comunitarista, na década de 1980, bem como em seus desdobramentos nas discussões acerca do multiculturalismo, na década seguinte. E ainda, mais recentemente, nos impasses em torno do papel da religião na esfera pública. Mais do que pontos divergentes acerca da questão do julgamento, os que essas discussões também evidenciam é um debate mais central acerca do lugar que pode ocupar a política diante de nossa situação bem como as categorias pelas quais compreendemos o fenômeno do pluralismo. Sob a alcunha de comunitarista, o pensamento de Taylor aparece como uma forma atrativa por não se submeter ao relativismo (a impossibilidade de critério) e tampouco a um universalismo forte (baseado em critérios gerais e anteriores às práticas), ao desenvolver uma ontologia fundada em um conflito de bens constitutivos em disputa, sem desconsiderar o fenômeno do pluralismo. Com efeito, isto se dá na medida em que diante de práticas divergentes e concorrentes há implícita ou explicitamente uma posição acerca de como e a partir de onde podemos nos posicionar criticamente frente ao pluralismo vigente, uma vez que movimentos, discursos e relações são construídos em nome daquilo que se apresenta efetivamente como valioso ou digno de respeito e admiração. Neste sentido, qualquer tentativa de avaliação já diz respeito a nossa compreensão: de nós, do mundo e de nossa relação com o mundo. Um projeto crítico, levando em consideração nossas fontes que impulsionam a ação, requer um olhar detalhado que o pensamento de Taylor pode oferecer, especialmente a partir da relação entre os conceitos supracitados.

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The biography of Charles Bradford Hudson that follows this preface had its seeds about 1965 when I (VGS) was casually examining the extensive files of original illustrations of fishes stored in the Division of Fishes, National Museum of Natural History, Smithsonian Institution. I happened upon the unpublished illustration of a rainbow trout by Hudson and was greatly impressed with its quality. The thought occurred to me then that the artist must have gone on to do more than just illustrate fishes. During the next 20 years I occasionally pawed through those files, which contained the work of numerous artists, who had worked from 1838 to the present. In 1985, I happened to discuss the files with my supervisor, who urged me to produce a museum exhibit of original fish illustrations. This I did, selecting 200 of the illustrations representing 21 artists, including, of course, Hudson. As part of the text for the exhibit, Drawn from the Sea, Art in the Service of Ichthyology, I prepared short biographies of each of the artists. The exhibit, with an available poster, was shown in the Museum for six months, and a reduced version was exhibited in U.S. and Canadian museums during the next 3 years.

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John Otterbein Snyder (1867–1943) was an early student of David Starr Jordan at Stanford University and subsequently rose to become an assistant professor there. During his 34 years with the university he taught a wide variety of courses in various branches of zoology and advised numerous students. He eventually mentored 8 M.A. and 4 Ph.D. students to completion at Stanford. He also assisted in the collection of tens of thousands of fish specimens from the western Pacific, central Pacific, and the West Coast of North America, part of the time while stationed as “Naturalist” aboard the U.S. Fish Commission’s Steamer Albatross (1902–06). Although his early publications dealt mainly with fish groups and descriptions (often as a junior author with Jordan), after 1910 he became more autonomous and eventually rose to become one of the Pacific salmon, Oncorhynchus spp., experts on the West Coast. Throughout his career, he was especially esteemed by colleagues as “a stimulating teacher,” “an excellent biologist,” and “a fine man.

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Charles Henry Gilbert (Fig. 1) was a pioneer ichthyologist and, later, fishery biologist of particular significance to natural history of the western United States. Born in Rockford, Illinois on 5 December 1859, he spent his early years in Indianapolis, Indiana, where, in 1874, he came under the influence of his high school teacher, David Starr Jordan (1851-1931). Gilbert graduated from high school in 1875, and when Jordan became a professor of natural history at Butler University in Irvington, Indiana, Gilbert followed, and received his B.A. degree in 1879. Jordan moved to Indiana University, in Bloomington, in the fall of 1879, and Gilbert again followed, earning his M.S. degree in 1882 and his Ph.D. in 1883 in zoology. His doctorate was the first ever awarded by Indiana University.

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Charles Henry Gilbert (1859-1928) was a pioneering ichthyologist who made major contributions to the study of fishes of the American West. As chairman of the Department ofZoology at Leland Stanford Junior University in Palo Alto, Calif., during 1891-1925, Gilbert was extremely devoted to his work and showed little patience with those ofa different mindset. While serving as Naturalist-in-Charge of the U.S. Fish Commission Steamer Albatross during her exploratory expedition to the Hawaiian Islands in 1902, Gilbert engaged in an acrimonious feud with the ship's captain, Chauncey Thomas, Jr. (1850-1919), U.S.N., over what Gilbert perceived to be an inadequate effort by the captain. This essay focuses on the conflict between two strong figures, each operatingf rom different world views, and each vying for authority. Despite the difficulties these two men faced, the voyage of the Albatross in 1902 must be considered a success, as reflected by the extensive biological samples collected, the many new species of animals discovered, and the resulting publication of important scientific papers.

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Fishery science pioneers often faced challenges in their field work that are mostly unknown to modern biologists. Some of the travails faced by ichthyologist and, later, fishery biologist Charles Henry Gilbert (1859-1928) during his service as Naturalist-in-Charge of the North Pacific cruise ofthe U.S. Bureau of Fisheries Steamer Albatross in 1906, are described here, as are accomplishments of the cruise. The vessel left San Francisco, Calif., on 3 May 1906, just after the great San Francisco earthquake, for scientific exploration of waters of the Aleutian islands, Bering Sea, Kamchatka, Sakhalin, and Japan, returning to San Francisco in December. Because the expedition occurred just after the war between Japan and Russia of 1904-05 floating derelict mines in Japanese waters were often a menace. Major storms caused havoc in the region, and the captain of the Albatross, Lieutenant Commander LeRoy Mason Garrett (1857-1906), U.S.N., was lost at sea, apparently thrown from the vessel during a sudden storm on the return leg of the cruise. Despite such obstacles, Gilbert and the Albatross successfully completed their assigned chores. They occupied 339 dredging and 48 hydrographic stations, and discovered over 180 new species of fishes and many new species of invertebrates. The expedition's extensive biological collections spawned over 30 descriptive publications, some of which remain today as standards of knowledge.

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Among the papers of Dr. Charles M. Breder bequeathed to the Mote Marine Laboratory by the Breder family are a series of drawings of larval fish and eggs done from 1917 through 1929. The drawings were made with pencil on half and full sheets of buff colored paper. The half sheet drawings are of larval fish, most of which are not identified. The full sheet drawings often contain comments and notes related to laboratory work on fish egg development, and made during the summer of 1929 when Breder was working in the Dry Tortugas.