973 resultados para Lawrence, C. W.


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Structures of poly(ether ether ketone ketone)-poly(ether biphenyl ether ketone ketone) copolymers were studied by using small angle X-ray scattering and the one-dimensional electron density correlation function method. The results revealed that structures of the aggregated state of the copolymers depend closely on the biphenyl content (n(b)). When n(b) = 0.35, invariant Q, long period L, average thickness of crystal lamellae (d) over bar, electron density difference eta(c) - eta(a) and degree of crystallinity W-c,W-x assume minimum values.

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The blend polyamide 1010/N,N'-(diphenylmethane-4,4'-diyl)bismaleimide (PA1010/ BMI) has been investigated by means of WAXD and SAXS. The results obtained with the help of the Ruland, variance and 1D EDCF analysis showed that the degree of crystallinity (W-c,W-x), crystallite size (L(hikl)), long period (L) and thickness of average crystal lamellae (d) decrease with BMI content. Experimental and calculated density values (rho(c)) are in good agreement. Addition of BMT to PA1010 causes an increase in structural distortion. The results from SAXS analysis also supported that a crystalline amorphous interphase exists in the lamellae of semicrystalline polymers, so that a three-phase model instead of the traditional two-phase model should be used.

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The influence of gamma-radiation on polyamide 1010 aggregate structures and crystal damage were examined by using wide angle X-ray diffraction (WAXD) and small angle X-ray scattering (SAXS) techniques. The results revealed that some structural parameters of the aggregated state, the density differences and the degree of crystallinity W-c,W-x, essentially decreased with increasing radiation dose, but the specific surface O-s increased. Crosslinking and scission of irradiated polyamide 1010 samples occurred mainly in amorphous and interphase regions, and crystal damage and amorphization induced by gamma-radiation spread from the interphase and extended into the crystal phase with increasing radiation dose. This result also indicated that the (010) reflection with the hydrogen bond was more susceptible to the action of radiation.

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The structural parameters of the aggregated state under various heat treatment for PA-1010 samples were computed by means of the desmearing intensity from SAYS, and by using the concept of the distance distribution function and 1D EDCF method. The results revealed that the maximum values of Q, I(0), P-max(Z), dtr, Rg and W-c,W-x were obtained nearby T=175 degreesC for PA-1010 samples with various annealing treatment. The higher degree of the crystallinity, the greater values of all the structural parameters of the aggregated state for PA-1010 samples were.

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RNA interference (RNAi) is an evolutionarily conserved mechanism by which double-stranded RNA (dsRNA) initiates post-transcriptional silencing of homologous genes. Here we report the amplification and characterisation of a full length cDNA from black tiger shrimp (Penaeus monodon) that encodes the bidentate RNAase III Dicer, a key component of the RNAi pathway. The full length of the shrimp Dicer (Pm Dcr1) cDNA is 7629 bp in length, including a 51 untranslated region (UTR) of 130 bp, a 3' UTR of 77 bp, and an open reading frame of 7422 bp encoding a polypeptide of 2473 amino acids with an estimated molecular mass of 277.895 kDa and a predicted isoelectric point of 4.86. Analysis of the deduced amino acid sequence indicated that the mature peptide contains all the seven recognised functional domains and is most similar to the mosquito (Aedes aegypti) Dicer-1 sequence with a similarity of 34.6%. Quantitative RT-PCR analysis showed that Pm Dcr1 mRNA is most highly expressed in haemolymph and lymphoid organ tissues (P 0.05). However, there was no correlation between Pm Dcr1 mRNA levels in lymphoid organ and the viral genetic loads in shrimp naturally infected with gill-associated virus (GAV) and Mourilyan virus (P > 0.05). Treatment with synthetic dsRNA corresponding to Pm Dcr1 sequence resulted in knock-down of Pm Dcr1 mRNA expression in both uninfected shrimp and shrimp infected experimentally with GAV. Knock-down of Pm Dcr1 expression resulted in more rapid mortalities and higher viral loads. These data demonstrated that Dicer is involved in antiviral defence in shrimp. (c) 2007 Elsevier Ltd. All rights reserved.

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The late stage of the North East Atlantic (NEA) spring bloom was investigated during June 2005 along a transect section from 45 to 66 degrees N between 15 and 20 degrees W in order to characterize the contribution of siliceous and calcareous phytoplankton groups and describe their distribution in relation to environmental factors. We measured several biogeochemical parameters such as nutrients, surface trace metals, algal pigments, biogenic silica (BSi), particulate inorganic carbon (PIC) or calcium carbonate, particulate organic carbon, nitrogen and phosphorus (POC, PON and POP, respectively), as well as transparent exopolymer particles (TEP). Results were compared with other studies undertaken in this area since the JGOFS NABE program. Characteristics of the spring bloom generally agreed well with the accepted scenario for the development of the autotrophic community. The NEA seasonal diatom bloom was in the late stages when we sampled the area and diatoms were constrained to the northern part of our transect, over the Icelandic Basin (IB) and Icelandic Shelf (IS). Coccolithophores dominated the phytoplankton community, with a large distribution over the Rockall-Hatton Plateau (RHP) and IB. The Porcupine Abyssal Plain (PAP) region at the southern end of our transect was the region with the lowest biomass, as demonstrated by very low Chla concentrations and a community dominated by picophytoplankton. Early depletion of dissolved silicic acid (DSi) and increased stratification of the surface layer most likely triggered the end of the diatom bloom, leading to coccolithophore dominance. The chronic Si deficiency observed in the NEA could be linked to moderate Fe limitation, which increases the efficiency of the Si pump. TEP closely mirrored the distribution of both biogenic silica at depth and prymnesiophytes in the surface layer suggesting the sedimentation of the diatom bloom in the form of aggregates, but the relative contribution of diatoms and coccolithophores to carbon export in this area still needs to be resolved.

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Oxytropis xinglongshanica C. W. Chang var. obesusi-corollata Y. H. Wu, var. nov. A var. xinglongshanica recedit corollis obesis, vexillis c. 15 mm longis, c. 10 mm latis, limbis late ovatis, unguibus c. 6 mm longis; alis c. 14 mm longis, c. 4.5 mm latis, limbis anguste obovatis.

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2009

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Esse manual para recuperacao de Matas de Galeria da regiao do Brasil Central enfatiza que os plantios devem utilizar especies nativas do local a ser reabilitado, respeitando as condicoes encontradas na microbacia, tais como umidade, fertilidade do solo e luminosidade. As sugestoes propostas procuram reestruturar o ambiente de forma que este retorne o mais rapido e semelhante possivel as condicoes originais, buscando atender a crescente demanda da sociedade e do governo que solicitam subsidios para recuperar matas que foram degradadas por causa das pressoes do desenvolvimento economico. O manual foi elaborado com base na experiencia dos autores, em pesquisas de campo e de laboratorio, alem de sintetizar informacoes disponiveis na literatura. O texto busca auxiliar na elaboracao e na execucao de projetos de revegetacao, fornecendo, por exemplo, elementos para a escolha das especies e as tecnicas mais adequadas de plantio. Assim, o ambiente Mata de Galeria e conceituado em seus dois tipos: inundavel e nao inundavel com suas principais especies. Em seguida, discutem-se aspectos da estrutura e da dinamica da vegetacao e fatores a serem considerados na recuperacao dessas matas. E fornecida tambem a listagem de 89 especies lenhosas, ressaltando suas caracteristicas em relacao a luz, ao porte, a fertilidade e a drenagem do solo, seus usos mais comuns e epoca de maturacao de frutos para a coleta das sementes. Recomendam-se plantios em curva de nivel, procurando respeitar a ocorrencia original das especies na mata, em relacao ao regime hidrico dos rios e suas margens. Sao ainda fornecidos subsidios para coleta de sementes e producao de mudas em viveiro e ainda tres modelos de plantio definitivo no campo, com a distribuicao esquematica de grupos de especies e recomendacoes para a sua manutencao.

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Wydział Historyczny: Instytut Etnologii i Antropologii Kulturowej

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Niniejszy tom stanowi zbiór artykułów, które podejmują próbę zarysowania problemów stojących przed współczesną dydaktyką języków obcych w polskim kontekście edukacyjnym, wskazując w wielu przypadkach na bardzo konkretne możliwości ich rozwiązywania, a co za tym idzie, usprawnienia procesu uczenia się i nauczania języka obcego na różnych poziomach kształcenia. Teksty te dotyczą bardzo zróżnicowanej problematyki, poczynając od zagadnień teoretycznych i ich przełożenia na sytuację szkolną, poprzez wyniki różnego typu projektów badawczych wraz z implikacjami dla nauczania języków obcych, po propozycje konkretnych metod i technik, narzędzi dydaktycznych i rozwiązań systemowych. Tom został podzielony na sześć rozdziałów, w których zgrupowane zostały prace poświęcone pokrewnej tematyce, przy czym kluczem przy ustalaniu ich kolejności były poruszane kwestie, a nie porządek alfabetyczny. Tak więc, w części pierwszej, zatytułowanej Między teorią a praktyką, można znaleźć artykuły, które pokazują, w jaki sposób różne dziedziny wiedzy i modele teoretyczne mogą stanowić ważny punkt odniesienia dla dydaktyki języków obcych. Rozdziały drugi i trzeci, zatytułowane Techniki, metody, narzędzia i Wykorzystanie nowoczesnych technologii, poświęcone zostały przedstawieniu różnorodnych metod i środków nauczania, które można wykorzystać we wprowadzaniu i ćwiczeniu podsystemów i sprawnci językowych oraz rozwijaniu autonomii ucznia i umiejętności samooceny. Z kolei rozdział czwarty, Nauczanie dzieci w wieku wczesnoszkolnym, grupuje teksty podejmujące problematykę dydaktyki języka obcego w odniesieniu do małych dzieci, ze szczególnym uwzględnieniem roli nauczyciela w tym obszarze. W rozdziale piątym, tj. Programy nauczania, etapy edukacyjne, egzaminy, zamieszczono artykuły, które podejmują kwestie o charakterze instytucjonalnym, dotyczące udoskonalenia edukacji językowej i ewaluacji postępów na różnych poziomach kształcenia. I w końcu, w części szóstej, zatytułowanej Kształcenie dwujęzyczne i specjalistyczne, znaleźć można prace poświęcone problematyce organizacji procesu nauczania treści merytorycznych przy użyciu języka obcego, specyfice nauczania języka polskiego jako obcego i wyzwaniom stojącym przed nauczycielem języka obcego dla potrzeb zawodowych. Jestem przekonany, że z uwagi na sw zróżnicowaną tematykę, umiejętne powiązanie teorii i badań empirycznych z codzienną praktyką, a co najważniejsze, uwzględnienie uwarunkowań i ograniczeń polskiego kontekstu edukacyjnego, niniejsza praca zbiorowa będzie stanowić ważne źródło inspiracji i refleksji dla wielu neofilologów, zarówno teoretyków i badaczy, jak i studentów filologii oraz nauczycieli różnych języków obcych.

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Wydział Filologii Polskiej i Klasycznej: Instytut Filologii Polskiej

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Building on the planning efforts of the RCN4GSC project, a workshop was convened in San Diego to bring together experts from genomics and metagenomics, biodiversity, ecology, and bioinformatics with the charge to identify potential for positive interactions and progress, especially building on successes at establishing data standards by the GSC and by the biodiversity and ecological communities. Until recently, the contribution of microbial life to the biomass and biodiversity of the biosphere was largely overlooked (because it was resistant to systematic study). Now, emerging genomic and metagenomic tools are making investigation possible. Initial research findings suggest that major advances are in the offing. Although different research communities share some overlapping concepts and traditions, they differ significantly in sampling approaches, vocabularies and workflows. Likewise, their definitions of 'fitness for use' for data differ significantly, as this concept stems from the specific research questions of most importance in the different fields. Nevertheless, there is little doubt that there is much to be gained from greater coordination and integration. As a first step toward interoperability of the information systems used by the different communities, participants agreed to conduct a case study on two of the leading data standards from the two formerly disparate fields: (a) GSC's standard checklists for genomics and metagenomics and (b) TDWG's Darwin Core standard, used primarily in taxonomy and systematic biology.

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A flexible elimination algorithm is presented and is applied to the solution of dense systems of linear equations. Properties of the algorithm are exploited in relation to panel element methods for potential flow and subsonic compressible flow. Further properties in relation to distributed computing are also discussed.