bluuebunny/crossref_metadata_2025 huggingface dataset:
Fungos anamórficos (Hyphomycetes) no Semi-árido do Estado da Bahia, Brasil
Authors: Barbosa Flavia Rodrigues , Gusmão Luís Fernando Pascholati , Barbosa Fabio Fernandes
Published: May 2008

Durante o levantamento de fungos anamórficos associados à folhas em decomposição de diferentes plantas na região semi-árida do Estado da Bahia, 23 espécies, pertencentes a 19 gêneros foram encontradas. Dessas, uma espécie constitui novo registro para a Bahia e três para o Brasil, respectivamente: Drechslera victoriae (F. Meehan & H.C. Murphy) Subram. & B.L. Jain, Ochroconis crassihumicola (Matsush.) de Hoog & Arx, Pyricularia caffera Matsush. e Tretopileus sphaerophorus (Berk & M.A. Curtis) Hughes & Deighton. Descrições, comentários e ilustrações são apresentados para essas espécies.
Características morfoanatômicas da epiderme foliar de plantas variantes e não variantes somaclonais de bananeiras (Musa sp. Colla cv. Prata-anã) cultivadas in vitro
Authors: Lacerda Guilherme Araújo , Silva Janaina de Oliveira Costa e , Abreu Juscélio Clemente de , Alves Eduardo , Paiva Luciano Vilela
Published: May 2008

A variação somaclonal corresponde ao aparecimento de plantas anormais durante o processo de multiplicação in vitro, principalmente relacionada à estatura, no caso o gigantismo. O objetivo deste trabalho foi averiguar as diferenças morfoanatômicas da epiderme foliar na tentativa de diferenciar as plantas de 'Prata-anã' em relação aos seus variantes somaclonais. A análise por microscopia eletrônica de varredura mostrou uma diferença significativa entre o diâmetro polar dos estômatos da 'Prata-anã' não variante e suas variantes, ambas em condições in vitro, observando-se que o mesmo não ocorre para as plantas in vivo. O número médio de estômatos é menor nas plantas variantes somaclonais, porém sem diferenças significativas a não ser para a planta PIII. A descamação de cera é evidente somente nas plantas variantes de ambos os materiais (in vitro e in vivo). Conclui-se que os caracteres morfoanatômicos da epiderme foliar, como densidade estomática, diâmetro estomático polar e a uniformidade da cera atuam como marcadores morfológicos para caracterizar as plantas micropropagadas de 'Prata-anã' em relação aos seus variantes somaclonais para a característica gigantismo.
Ocorrência de Euglenophyceae pigmentadas em rizipiscicultura na Região do Vale do Itajaí, SC, Sul do Brasil
Authors: Alves-da-Silva Sandra Maria , Tamanaha Márcio da Silva
Published: May 2008

O estudo de uma amostra oriunda do cultivo de arroz irrigado (Oriza sativa L.) associado com criação de carpa comum (Cyprinus carpio Linnaeus, 1758), em um ambiente raso (20 m² × 0,30 m de prof.), na Região do Vale do Itajaí, Santa Catarina (26º53'33''S, 048º49'41''W), resultou na identificação de 48 morfoespécies da classe Euglenophyceae, representados pelos gêneros Euglena, Lepocinclis, Phacus, Strombomonas e Trachelomonas. O gênero Trachelomonas foi o que apresentou o maior número de táxons (26%). Destacou-se Euglena caudata Hübnere Euglena sanguinea Ehr. pelo elevado número de indivíduos por lâmina. Vinte e oito táxons são primeiras citações de ocorrência para o estado de Santa Catarina. São fornecidas descrições, chaves dicotômicas, dimensões, relação entre o comprimento e a largura celular (Rc/l), ilustrações dos táxons e distribuição geográfica mundial.
A aplicação precoce de nitrogênio em cobertura não aumenta o rendimento de grãos do trigo cultivado na presença do alumínio
Authors: Sangoi Luís , Almeida Milton Luiz de , Pucci Ana Lúcia Ramos , Strieder Marciane , Zanin Claitson Gustavo , Silva Leonardo Cury da , Vieira Rogério Junior
Published: May 2008

A época de realização da adubação nitrogenada de cobertura pode interferir sobre a participação dos afilhos no rendimento de grãos do trigo em solos ácidos. Este trabalho objetivou avaliar a interação entre o efeito inibidor do alumínio e a época de aplicação do nitrogênio sobre o desempenho agronômico do trigo. Foram conduzidos três experimentos, em telado, a campo e em câmara de crescimento, nos anos de 2000, 2002 e 2003. A campo e em telado, foram testados três níveis de correção do solo (sem correção, ¼ da dose e dose integral de calcário para elevar o pH até 6,0) e quatro épocas de aplicação de nitrogênio em cobertura (emergência, estádios 1,5, 3,1 e 4,1 da escala Haun). Em câmara de crescimento, testaram-se três doses de alumínio (0, 8 e 32mg L-1) e quatro épocas de aumento da concentração de nitrogênio na solução nutritiva. Avaliaram-se o rendimento de grãos, o acúmulo de matéria seca e o teor de N no colmo principal e afilhos. Não houve efeito da interação entre os níveis de correção do solo e a época de aplicação do nitrogênio sobre o rendimento de grãos. Independentemente da presença do alumínio, a aplicação precoce de N (emergência ou 1,5 folhas) não incrementou o rendimento de grãos do trigo, em relação às coberturas mais tardias. Assim, a antecipação da cobertura nitrogenada não foi capaz de mitigar os efeitos inibitórios do alumínio, nem de aumentar o acúmulo de matéria seca nos afilhos e a sua participação no rendimento de grãos.
Microenxertia e sua caracterização morfológica em Araucaria angustifolia
Authors: Anselmini Justina Inês , Zanette Flávio
Published: May 2008

O objetivo deste trabalho foi determinar a melhor técnica para microenxertia em Araucaria angustifolia. Para isto, foram realizadas auto-enxertias em plantas germinadas in vitro, com 2, 6 e 12 meses de idade. Foram testados dois locais de enxertia no porta-enxerto: caule e hipocótilo, e dois tipos de enxertia: garfagem de topo com e sem fenda. A maior porcentagem de microenxertos com fenda aberta ocorreu nas microenxertias realizadas no hipocótilo. As maiores porcentagens de microenxertos sobreviventes foram obtidas nas microenxertias realizadas no caule, e o tipo de enxertia mais eficiente foi a garfagem de topo sem fenda. A presença de calo aparente foi resultado da interação dos três fatores testados, com maior presença de calo nas enxertias realizadas no hipocótilo. O crescimento dos microenxertos indicou o restabelecimento das conexões vasculares. O maior crescimento dos microenxertos foi obtido nas enxertias realizadas no caule em porta-enxertos de 6 meses com a garfagem de topo. As metodologias testadas permitem concluir que o processo de microenxertia em Araucaria angustifolia é eficiente e factível, podendo ser utilizado para a produção de mudas microenxertadas.
Relationship between clinical and postmortem evaluation in repeat breeder beef cows
Authors: Ferreira Rogério , Oliveira João Francisco Coelho de , Antoniazzi Alfredo Quites , Pimentel Cláudio Alves , Moraes José Carlos Ferrugem , Henkes Luiz Ernani , Bordignon Vilceu , Gonçalves Paulo Bayard Dias
Published: May 2008

The objective of this study was to investigate the causes of the repeat breeder syndrome comparing clinical signs and postmortem findings in beef cows. The identification of factors affecting the reproductive tract can support decisions as to whether treatment of repeat breeder cows is justifiable than culling. Since all animals were submitted to clinical examination before being slaughtered, this study has a differential approach when compared with others, where genital tracts from abattoir were examined. In this study, 130 crossbred cows and heifers that have failed to conceive after three or more services were identified, submitted to a clinical examination and blood collection for karyotyping and sent to an abattoir. postmortem examinations included macroscopic evaluation of the genital tracts, bacteriology and histopathology of the uterus. Uterine alterations were predominant followed by oviduct and ovarian pathologies. Histopathological examination was more sensitive as a diagnostic tool than clinical examination. Repeat breeder cows had a predominance of uterine abnormalities (95%), such as inflammatory (42.9%) and degenerative (59.7%) conditions. Oviduct abnormalities were found in 29.8 % of animals. Furthermore, 1 out 10 karyotyped cows showed aneuploidy. Thus, this study stressed the importance of laboratory exams in the diagnosis of the causes of infertility of repeat breeder cows.
Parcelamento da adubação nitrogenada na cultura do milho e utilização do N residual pela sucessão aveia preta-milho
Authors: Fernandes Flávia Carvalho Silva , Libardi Paulo Leonel , Trivelin Paulo César Ocheuze
Published: May 2008

Com o objetivo de avaliar a eficiência de utilização do N pela cultura de milho (Zea mays L.), usando-se fertilizante marcado com 15N, aplicado parceladamente (duas formas), e o efeito residual deste fertilizante nas duas culturas subseqüentes em sucessão (aveia preta e milho), sob implantação do sistema plantio direto, foi conduzido um experimento, no sudeste do Brasil, nos anos agrícolas 2003/2004 e 2004/2005, sob um solo de textura areno-argilosa (Hapludox). Os tratamentos consistiram da dose de 120kg ha-1 de N, na forma de sulfato de amônio marcado (15N) e dois parcelamentos de N 30-90 e 60-60kg ha-1. Nas plantas de milho e aveia preta, avaliaram-se o N total acumulado, o N proveniente do fertilizante e a recuperação de N-fertilizante. O incremento da dose de fertilizante nitrogenado aplicado na semeadura (60kg ha-1 de N), no ano agrícola 2003/2004, proporcionou aumento no aproveitamento de N pela planta (65%) em relação ao tratamento que recebeu 30kg ha-1 de N na semeadura (45%).
Profundidades de semeadura para emergência de plântulas de juazeiro
Authors: Alves Edna Ursulino , Bruno Riselane de Lucena Alcântara , Alves Anarlete Ursulino , Alves Adriana Ursulino , Cardoso Edson de Almeida , Dornelas Carina Seixas Maia , Galindo Evio Alves , Braga Júnior Joel Martins
Published: May 2008

Juazeiro (Zizyphus joazeiro Mart.) é uma árvore brasileira típica dos sertões nordestinos. Endêmica da Caatinga, ela ocorre nos diversos Estados do Nordeste do Brasil e apresenta grande potencial econômico e é importante para a região semi-árida. Assim, este estudo teve como objetivo determinar a melhor profundidade de semeadura para a emergência de plântulas de Zizyphus joazeiro. O experimento foi realizado em casa-de-vegetação, tendo como substrato areia lavada e esterilizada contida em bandejas de plástico, com 4 repetições de 25 unidades de dispersão cada uma, nas seguintes profundidades (um, dois, três, quatro e cinco centímetros). A semeadura de juazeiro em ambiente protegido deve ser feita na profundidade entre 1,0 e 1,6cm, resultando em elevado aproveitamento das unidades de dispersão. A profundidade de 1cm resultou em menor tempo para a germinação total.
Leito de drenagem: sistema natural para redução de volume de lodo de estação de tratamento de água
Authors: Achon Cali Laguna , Barroso Marcelo Melo , Cordeiro João Sérgio
Published: May 2008

As Estações de Tratamento de Água (ETAs) tem funcionamento semelhante a uma indústria e podem em diversas etapas gerar resíduos que, na maioria das ETAs, são lançados nos corpos d’água sem tratamento. Neste trabalho avaliou-se o desempenho de Leitos de Drenagem, para o desaguamento de lodo, provenientes de ETAs de ciclo completo que empregam sulfato de alumínio e cloreto de polialumínio (PACl), como coagulantes. Analisou-se as características, a drenagem e secagem dos amostras de lodo e característica do drenado. Os Leitos de Drenagem mostraram-se eficientes para desaguamento e redução de volume de lodo de ETA, de forma natural, sem consumo de energia ou adição de produtos químicos. Obteve-se, aos sete dias, reduções da ordem de 87 % em volume para os lodos de PACl e 83 % para o lodo de Sulfato de Alumínio e teor de sólidos totais 28% e 31% respectivamente.
Responses of six Brachiaria spp. accessions to root zone flooding
Authors: Caetano Luana Pabla de Souza , Dias-Filho Moacyr Bernardino
Published: May 2008

Some morphophysiological responses of Brachiaria brizantha cv. Marandu, cv. Piatã, cv. Arapoty, B163, B166 and B. ruziziensis R124 were compared in plants grown in pots, under flooded and well-drained conditions. Flooding reduced leaf elongation rate in all accessions. Leaf dry mass production was lower under flooding than in the control plants in all the studied accessions, except in cv. Piatã. Root dry mass production was reduced by flooding in cv. Marandu and in R124, while the proportion of biomass allocated to roots was reduced by flooding only in R124. It was not possible to detect significant differences between water regimes in the percentage of biomass allocated to culms and leaves for all accessions. Flooding decreased the number of tillers in cv. Marandu, in B163, B166 and in R124. Relative growth rate was decreased by flooding in cv. Marandu, in B163 and in R124. Flooding reduced gas exchange parameters in all accessions, but cv. Arapoty. The accessions tested differ in their relative tolerance to flooding. B. brizantha cv. Arapoty is considered the most tolerant. B. ruziziensis R124 is the most sensitive, followed by B. brizantha cv. Marandu. B. brizantha cv. Piatã, B163 and B166 are intermediate in flooding tolerance.
Divergência genética entre linhagens de matrizes de corte por meio de análise de agrupamento
Authors: Yamaki Marcos , Menezes Gilberto Romeiro de Oliveira , Teixeira Rafael Bastos , Barbosa Leandro , Paiva André Luis da Costa , Torres Robledo de Almeida
Published: May 2008

Este trabalho foi realizado com o objetivo de avaliar a divergência genética de três linhagens de matrizes de corte do Programa de Melhoramento Genético da UFV. Foram avaliados dados de 270 aves, 90 de cada linhagem, para estudo das características dias para o primeiro ovo (DPPO), taxa de postura da 22ª à 56ª semana (TP), peso médio individual na 32ª (PMI1), 40ª (PMI2), 48ª (PMI3), 56ª (PMI4) e 64ª semanas de idade (PMI5); e peso médio do ovo, obtido pela média da pesagem de três ovos na 32ª (PMO1), 40ª (PMO2), 48ª (PMO3), 56ª (PMO4) e 64ª semanas de idade (PMO5). Para avaliar a divergência, foram utilizados dois métodos: hierárquico do vizinho mais próximo e otimização de Tocher. Pelo método hierárquico do vizinho mais próximo, utilizando-se a distância de Mahalanobis ao quadrado (D²) como medida de dissimilaridade, formou-se um único grupo. Pelo método de otimização de Tocher, foram formados dois grupos, comprovando que os dois métodos foram discordantes na avaliação da divergência genética de linhas de aves de corte. As características que apresentaram as contribuições relativas mais expressivas para a divergência foram, respectivamente, PMO1 (25,71%), DDPO (21,76%), PMI4 (17,65%) e PMI2 (13,04%).
Níveis de concentrado na dieta de bovinos Nelore de três condições sexuais: consumo, digestibilidades total e parcial, produção microbiana e parâmetros ruminais
Authors: Véras Robson Magno Liberal , Valadares Filho Sebastião de Campos , Azevêdo José Augusto Gomes , Detmann Edenio , Paulino Pedro Veiga Rodrigues , Barbosa Analívia Martins , Marcondes Marcos Inácio
Published: May 2008

Doze bovinos Nelore de três condições sexuais (CS) - quatro fêmeas, quatro machos castrados e quatro machos não-castrados - com idade aproximada de 15 meses e peso corporal médio de 235, 249 e 239 kg, respectivamente, foram distribuídos em delineamento inteiramente casualizado, em esquema fatorial 2 × 3, composto de dois níveis de concentrado (25 ou 50%) e três CS, objetivando-se estudar o consumo, as digestibilidades total e parcial dos nutrientes, a produção microbiana e os parâmetros ruminais. As coletas de líquido ruminal, para determinação do pH e da concentração de amônia, foram realizadas imediatamente antes do fornecimento da dieta e 2, 4 e 6 horas após a alimentação. Não houve interação significativa de níveis de concentrado e CS para nenhum dos consumos observados. Os consumos de MS, MO, EE, PB, CNF e NDT, em kg/dia, e de MS em % do PC ou em g/kg0,75, não foram influenciados pelos níveis de concentrado ou pela condição sexual. Não houve interação de níveis de concentrados × CS para as digestibilidades totais e parciais dos nutrientes, com exceção do EE. O aumento do nível de concentrado reduziu a digestibilidade da FDN. Os teores médios de N nas bactérias variaram de 7,39 a 6,91%. O fluxo de nutrientes e a eficiência microbiana expressa de diferentes formas, com exceção de gNmic/kgMODR, não foram influenciados pelos níveis de concentrados ou pela condição sexual. A concentração de NH3 máxima de 14,55 mg/dL foi estimada 1,83 hora após a alimentação. O aumento dos níveis de concentrado na dieta não resultou em respostas positivas para os consumos, as digestibilidades parciais e totais da maioria dos nutrientes e a produção microbiana.
Predição das propriedades elásticas de compósitos termoestruturais com reforço multidirecional
Authors: Ribeiro J.L.P. , Gregori M.L. , Pardini L.C.
Published: May 2008

Os compósitos são uma classe de materiais que apresentam propriedades superlativas em relação aos materiais isotrópicos (metais, cerâmicos, polímeros), se considerarmos sua alta resistência aliada ao baixo peso. O reforço, a matriz e a interface entre ambos, definem o desempenho do componente em serviço e a temperatura de trabalho destes materiais. Particularmente, compósitos de uso a temperaturas superiores à 1000ºC são denominados de compósitos termoestruturais. Estes materiais suportam demandas termo-mecânicas significativas, sendo utilizados em gargantas de tubeira de foguetes, proteções térmicas re-irradiativas e materiais de fricção. Via de regra, esses materiais são manufaturados mediante a utilização de preformas fibrosas, que nada mais são que um "esqueleto" de reforço que translada resistência e rigidez ao material. A utilização de preformas permite a concepção e obtenção de componentes com geometrias complexas e dimensões as mais diversas, permitindo assim uma flexibilidade no projeto do componente a ser obtido. Embora apresentem virtudes incontestáveis, o custo desses materiais ainda é proibitivo para aplicações rotineiras. Também o custo dos testes mecânicos que validem suas propriedades em relação aos materiais de uso convencional torna-se oneroso, além de demandar equipamentos especiais. O presente trabalho aborda a predição das propriedades elásticas de compósitos termoestruturais de Carbono Reforçado com Fibras de Carbono (CRFC), com configurações de reforço tri-direcional (3D) e tetra-direcional (4D). As propriedades foram calculadas à temperatura ambiente para efeito de comparação ao grafite sintético, ainda utilizado em gargantas de tubeira de motores foguete de pequeno porte. Os cálculos de predição de propriedades elásticas foram baseados no método de homogeneização considerando a hipótese de mechas de fibras retas pela rigidez média ponderada.
Identificação e avaliação dos mecanismos de ataque da escória SiO2-CaO-Al2O3-MgO em tijolos refratários de MgO-C
Authors: Trommer R.M. , Correia Lima A.N. , Vicenzi J. , Zimmer A. , Bragança S.R. , Bergamann C.P.
Published: May 2008

O presente trabalho tem como objetivo identificar e caracterizar mecanismos responsáveis pelo desgaste dos tijolos refratários de magnésia-carbono de uma panela de aciaria, devido ao ataque da escória SiO2-CaO-Al2O3-MgO. Para tanto, tijolos refratários MgO-C utilizados na linha de escória de uma panela industrial foram comparados com tijolos após o uso (post mortem). A microestrutura da região interfacial escória / refratário foi avaliada por análises mineralógicas (difração de raios X), microscopia eletrônica de varredura e microscopia óptica (lâminas petrográficas). Foi possível constatar que o tijolo post mortem apresenta, além das fases já existentes in natura, novas fases como a alumina, o silicato de cálcio e a gelenita devido à sua reação com a escória. Os resultados sugerem que o principal meio de degradação do tijolo se estabeleça pela infiltração da escória na matriz entre os grãos do tijolo refratário. Isto ocasiona o arrancamento de grãos, comprometendo a microestrutura original do material refratário, diminuindo seu tempo de vida útil.
NECROMASS PRODUCTION: STUDIES IN UNDISTURBED AND LOGGED AMAZON FORESTS
Authors: Palace Michael , Keller Michael , Silva Hudson
Published: May 2008

Necromass stocks account for up to 20% of carbon stored in tropical forests and have been estimated to be 14–19% of the annual aboveground carbon flux. Both stocks and fluxes of necromass are infrequently measured. In this study, we directly measured the production of fallen coarse necromass (≥2 cm diameter) during 4.5 years using repeated surveys in undisturbed forest areas and in forests subjected to reduced‐impact logging at the Tapajos National Forest, Belterra, Brazil (3.08° S, 54.94° W). We also measured fallen coarse necromass and standing dead stocks at two times during our study. The mean (SE) annual flux into the fallen coarse necromass pool in undisturbed forest of 6.7 (0.8) Mg·ha−1·yr−1 was not significantly different from the flux under a reduced‐impact logging of 8.5 (1.3) Mg·ha−1·yr−1. With the assumption of steady state, the instantaneous decomposition constants for fallen necromass in undisturbed forests were 0.12 yr−1 for large, 0.33 yr−1 for medium, and 0.47 yr−1 for small size classes. The mass weighted decomposition constant was 0.15 yr−1 for all fallen coarse necromass. Standing dead wood had a residence time of 4.2 years, and ∼0.9 Mg·ha−1·yr−1 of this pool was respired annually to the atmosphere through decomposition. Coarse necromass decomposition at our study site accounted for 12% of total carbon re‐mineralization, and total aboveground coarse necromass was 14% of the aboveground biomass. Use of mortality rates to calculate production of coarse necromass leads to an underestimation of coarse necromass production by 45%, suggesting that nonlethal disturbance such as branch fall contributes significantly to this flux. Coarse necromass production is an important component of the tropical forest carbon cycle that has been neglected in most previous studies or erroneously estimated.
SINK POPULATIONS IN CARNIVORE MANAGEMENT: COUGAR DEMOGRAPHY AND IMMIGRATION IN A HUNTED POPULATION
Authors: Robinson Hugh S. , Wielgus Robert B. , Cooley Hilary S. , Cooley Skye W.
Published: May 2008

Carnivores are widely hunted for both sport and population control, especially where they conflict with human interests. It is widely believed that sport hunting is effective in reducing carnivore populations and related human–carnivore conflicts, while maintaining viable populations. However, the way in which carnivore populations respond to harvest can vary greatly depending on their social structure, reproductive strategies, and dispersal patterns. For example, hunted cougar (Puma concolor) populations have shown a great degree of resiliency. Although hunting cougars on a broad geographic scale (>2000 km2) has reduced densities, hunting of smaller areas (i.e., game management units, <1000 km2), could conceivably fail because of increased immigration from adjacent source areas. We monitored a heavily hunted population from 2001 to 2006 to test for the effects of hunting at a small scale (<1000 km2) and to gauge whether population control was achieved (λ ≤ 1.0) or if hunting losses were negated by increased immigration allowing the population to remain stable or increase (λ ≥ 1.0). The observed growth rate of 1.00 was significantly higher than our predicted survival/fecundity growth rates (using a Leslie matrix) of 0.89 (deterministic) and 0.84 (stochastic), with the difference representing an 11–16% annual immigration rate. We observed no decline in density of the total population or the adult population, but a significant decrease in the average age of independent males. We found that the male component of the population was increasing (observed male population growth rate, λOM= 1.09), masking a decrease in the female component (λOF= 0.91). Our data support the compensatory immigration sink hypothesis; cougar removal in small game management areas (<1000 km2) increased immigration and recruitment of younger animals from adjacent areas, resulting in little or no reduction in local cougar densities and a shift in population structure toward younger animals. Hunting in high‐quality habitats may create an attractive sink, leading to misinterpretation of population trends and masking population declines in the sink and surrounding source areas.
ASSESSING MODEL STRUCTURE UNCERTAINTY THROUGH AN ANALYSIS OF SYSTEM FEEDBACK AND BAYESIAN NETWORKS
Authors: Hosack Geoffrey R. , Hayes Keith R. , Dambacher Jeffrey M.
Published: May 2008

Ecological predictions and management strategies are sensitive to variability in model parameters as well as uncertainty in model structure. Systematic analysis of the effect of alternative model structures, however, is often beyond the resources typically available to ecologists, ecological risk practitioners, and natural resource managers. Many of these practitioners are also using Bayesian belief networks based on expert opinion to fill gaps in empirical information. The practical application of this approach can be limited by the need to populate large conditional probability tables and the complexity associated with ecological feedback cycles. In this paper, we describe a modeling approach that helps solve these problems by embedding a qualitative analysis of sign directed graphs into the probabilistic framework of a Bayesian belief network. Our approach incorporates the effects of feedback on the model's response to a sustained change in one or more of its parameters, provides an efficient means to explore the effect of alternative model structures, mitigates the cognitive bias in expert opinion, and is amenable to stakeholder input. We demonstrate our approach by examining two published case studies: a host–parasitoid community centered on a nonnative, agricultural pest of citrus cultivars and the response of an experimental lake mesocosm to nutrient input. Observations drawn from these case studies are used to diagnose alternative model structures and to predict the system's response following management intervention.
INCORPORATING PRIVATE LANDS IN CONSERVATION PLANNING: PROTECTED AREAS IN BRITAIN
Authors: Jackson Sarah F. , Gaston Kevin J.
Published: May 2008

Evaluations of the effectiveness of protected areas often report their inadequate representation of regional variation in environmental conditions, land cover, and biological diversity. One frequent contributory explanation is the heavy reliance placed upon the designation of public as opposed to private lands for statutory protection. Given that protected area designation in Britain has no such constraint, and indeed that more than half of such areas are on private lands, we tested the a priori assumption that within this region the representation of environmental conditions and land cover within statutory protected areas would be more equitable. Despite the reduction in land ownership constraints on where protected areas can be established, a marked bias in protected area coverage remains. Protected areas in Britain tend toward regions of higher elevation, soils of lower economic potential, and coastal/estuarine habitat and fail adequately to represent areas of lower elevation and woodland habitats. Improving the current situation requires not only a more systematic approach to site selection, but a more equitable and diverse portfolio of incentives for private landowners to facilitate the decision to manage sites for conservation.
ROLES OF SURVIVAL AND DISPERSAL IN REINTRODUCTION SUCCESS OF GRIFFON VULTURE (GYPS FULVUS)
Authors: Gouar Pascaline Le , Robert Alexandre , Choisy Jean-Pierre , Henriquet Sylvain , Lecuyer Philippe , Tessier Christian , Sarrazin François
Published: May 2008

The success of reintroduction programs greatly depends on the amount of mortality and dispersal of the released individuals. Although local environmental pressures are likely to play an important role in these processes, they have rarely been investigated because of the lack of spatial replicates of reintroduction. In the present study, we analyzed a 25‐year data set encompassing 272 individuals released in five reintroduction programs of Griffon Vultures (Gyps fulvus) in France to examine the respective roles of survival and dispersal in program successes and failures. We use recent developments in multi‐strata capture–recapture models to take into account tag loss in survival estimates and to consider and estimate dispersal among release areas. We also examined the effects of sex, age, time, area, and release status on survival, and we tested whether dispersal patterns among release areas were consistent with habitat selection theories. Results indicated that the survival of released adults was reduced during the first year after release, with no difference between sexes. Taking into account local observations only, we found that early survival rates varied across sites. However when we distinguished dispersal from mortality, early survival rates became equal across release sites. It thus appears that among reintroduction programs difference in failure and success was due to differential dispersal among release sites. We revealed asymmetrical patterns of dispersal due to conspecific attraction: dispersers selected the closest and the largest population. We showed that mortality can be homogeneous from one program to another while, on the contrary, dispersal is highly dependent on the matrix of established populations. Dispersal behavior is thus of major interest for metapopulation restoration and should be taken into account in planning reintroduction designs.
U-Pb single zircon grain dating of Present fluvial and Cenozoic aeolian sediments from Gabon: consequences on sediment provenance, reworking, and erosion processes on the equatorial West African margin
Authors: Seranne Michel , Bruguier Olivier , Moussavou Mathieu
Published: May 2008

U-Pb ages obtained from detrital zircon from terrigenous sediments are used to determine the sources. Present fluvial sand-bars of the Ogooué river yield age spectra of detrital zircons in agreement with Archean and Early Proterozoic sources found in the drainage. The large proportion of Late Proterozoic zircons cannot be derived from primary erosion of the watershed basement rocks, since there is no formation of that age in the area.

This later group of zircons is in good agreement with reworking of the aeolian Paleogene Batéké Sands, by regressive erosion in the upper reaches of the Ogooué river, as they contain a majority of Late Proterozoic age zircons. The sources of Late Proterozoic zircons in the Batéké Sand are very distant, and transported and reworked – at least in part – by aeolian processes. Our results, together with the widely distributed Paleogene sediments over continental Africa, suggests that Paleogene was a time of subdued erosion of the cratonic areas and extensive reworking, transport and deposition within continental Africa. In contrast, our results from the Ogooué river indicate active present incision of the cratonic area, erosion of the previous continental sediments, and export of the river bed-load to the continental margin. This temporal evolution of erosion-transport-deposition is correlated with the drastic climate change that occurred during the Cenozoic, leading to a more efficient mechanical erosion, and it correlates with the increase of terrigenous flux to the margin, observed during the Neogene.
A possible capture of molybdenum during early diagenesis of dysoxic sediments
Authors: Tribovillard Nicolas , Lyons Timothy W. , Riboulleau Armelle , Bout-Roumazeilles Viviane
Published: May 2008

Molybdenum is a trace metal commonly used as a marker of paleoredox conditions of ancient depositional settings. Pyrite is an important molybdenum (Mo) host for enriched sedimentary rocks. In this paper we study the relationship between Mo and pyrite in the Bancs Jumeaux Formation, a Jurassic succession in northern France consisting of limestone and pyrite-rich marls. This formation is relatively enriched in Mo compared to other redox-sensitive trace metals. Our approach is grounded on bulk rock chemical analysis and delineation of two contrasting types of pyrite that can be extracted from the rocks: polyframboids and nonframboidal concretionary masses. The morphological characteristics of both morphotypes were studied using scanning electronic microscopy. The polyframboids are richer in Mo than the concretions but are not markedly enriched in other trace metals. This discrepancy in geochemical composition could result from pyrite precipitation at different times during early diagenesis. Our results tend to indicate that the polyframboids would have formed very early in reducing “microniches”, within dominantly dysoxic sediment. This early pyrite precipitation occurred at shallow depth below the sediment-water interface close to the abundant Mo source in overlying oxic seawater (molybdate ions), and would have fostered Mo-capture by the polyframboids in relatively large amounts. The concretions would have formed later during early diagenesis (within the sulfidic zone) under conditions of more limited Mo availability.
Late Holocene palaeohydrology of lake Afourgagh (Middle-Atlas, Morocco) from deposit geometry and facies
Authors: Detriche Sebastien , Breheret Jean-Gabriel , Zarki Hamid , Karrat L’houcine , Macaire Jean-Jacques , Fontugne Michel
Published: May 2008

The geometry and facies of deposits in lake Afourgagh (Middle-Atlas, Morocco) provide evidence for successive major lake level fluctuations during the last 2,500 years. Sedimentation is mainly biogenic with the laying down of thick charophyte-rich tufas interbedded with silty layers in distal areas and palaeosols in proximal areas. These alternations point to four major deposit sequences with lowstand phases. The first two phases are dated at ca. 2426 and 1869 cal B.P. These events appear to be linked to major arid episodes on a regional scale. However, climatic impact has been modulated by human activities, particularly during recent decades.
The ‘Mur des douaniers’, an exceptionally well-preserved Early Eifelian fossil site
Authors: Crônier Catherine , van Viersen Allart
Published: May 2008

The ‘Mur des douaniers’ biota at the former French/Belgian border contains a rich and diversified Lower Eifelian benthic fauna, and especially trilobites. Palaeobiodiversity and sedimentological analyses have led to the interpretation of the general palaeoenvironmental/palaeoecological context. This trilobite-rich locality is an exceptionally well-preserved Early Eifelian fossil site with regard to the regional scale. Unfortunately, its growing reputation led to fossil pillage and now this palaeontological site is protected as a Nature Reserve. From now on, no complementary observation of the palaeontological data, the taphonomic analysis, the ichnological, sedimentological and geochemical record can be made to provide a better palaeoecological synthesis.
Role of the Transcription Factor Sox4 in Insulin Secretion and Impaired Glucose Tolerance
Authors: Goldsworthy Michelle , Hugill Alison , Freeman Helen , Horner Emma , Shimomura Kenju , Bogani Debora , Pieles Guido , Mijat Vesna , Arkell Ruth , Bhattacharya Shoumo , Ashcroft Frances M. , Cox Roger D.
Published: May 2008

OBJECTIVES— To identify, map, clone, and functionally validate a novel mouse model for impaired glucose tolerance and insulin secretion.

RESEARCH DESIGN AND METHODS— Haploinsufficiency of the insulin receptor and associated mild insulin resistance has been used to sensitize an N-ethyl-N-nitrosourea (ENU) screen to identify novel mutations resulting in impaired glucose tolerance and diabetes. The new impaired glucose tolerance 4 (IGT4) model was selected using an intraperitoneal glucose tolerance test and inheritance of the phenotype confirmed by generation of backcross progeny. Segregation of the phenotype was correlated with genotype information to map the location of the gene and candidates sequenced for mutations. The function of the SRY-related high mobility group (HMG)-box 4 (Sox4) gene in insulin secretion was tested using another ENU allele and by small interfering RNA silencing in insulinoma cells.

RESULTS— We describe two allelic autosomal dominant mutations in the highly conserved HMG box of the transcription factor Sox4. Previously associated with pancreas development, Sox4 mutations in the adult mouse result in an insulin secretory defect, which exhibits impaired glucose tolerance in association with insulin receptor+/−–induced insulin resistance. Elimination of the Sox4 transcript in INS1 and Min6 cells resulted in the abolition of glucose-stimulated insulin release similar to that observed for silencing of the key metabolic enzyme glucokinase. Intracellular calcium measurements in treated cells indicate that this defect lies downstream of the ATP-sensitive K+ channel (KATP channel) and calcium influx.

CONCLUSIONS— IGT4 represents a novel digenic model of insulin resistance coupled with an insulin secretory defect. The Sox4 gene has a role in insulin secretion in the adult β-cell downstream of the KATP channel.
Thymic Stromal Lymphopoietin and Thymic Stromal Lymphopoietin–Conditioned Dendritic Cells Induce Regulatory T-Cell Differentiation and Protection of NOD Mice Against Diabetes
Authors: Besin Gilles , Gaudreau Simon , Ménard Michaël , Guindi Chantal , Dupuis Gilles , Amrani Abdelaziz
Published: May 2008

OBJECTIVE—Autoimmune diabetes in the nonobese diabetic (NOD) mouse model results from a breakdown of T-cell tolerance caused by impaired tolerogenic dendritic cell development and regulatory T-cell (Treg) differentiation. Re-establishment of the Treg pool has been shown to confer T-cell tolerance and protection against diabetes. Here, we have investigated whether murine thymic stromal lymphopoietin (TSLP) re-established tolerogenic function of dendritic cells and induced differentiation and/or expansion of Tregs in NOD mice and protection against diabetes.

RESEARCH DESIGN AND METHODS—We examined the phenotype of TSLP-conditioned bone marrow dendritic cells (TSLP-DCs) of NOD mice and their functions to induce noninflammatory Th2 response and differentiation of Tregs. The functional relevance of TSLP and TSLP-DCs to development of diabetes was also tested.

RESULTS—Our results showed that bone marrow dendritic cells of NOD mice cultured in the presence of TSLP acquired signatures of tolerogenic dendritic cells, such as an absence of production of pro-inflammatory cytokines and a decreased expression of dendritic cell costimulatory molecules (CD80, CD86, and major histocompatibility complex class II) compared with LPS-treated dendritic cells. Furthermore, TSLP-DCs promoted noninflammatory Th2 response and induced the conversion of naïve T-cells into functional CD4+CD25+Foxp3+ Tregs. We further showed that subcutaneous injections of TSLP for 6 days or a single intravenous injection of TSLP-DCs protected NOD mice against diabetes.

CONCLUSIONS—Our study demonstrates that TSLP re-established a tolerogenic immune response in NOD mice and protects from diabetes, suggesting that TSLP may have a therapeutic potential for the treatment of type 1 diabetes.
Migration of faceted high-angle grain boundaries in Zn
Authors: Gottstein G. , Shvindlerman L. S. , Sursaeva V. G.
Published: May 2008

The migration of a faceted high angle tilt grain boundary 85° in Zn was investigated. The migration behavior complies with theoretical predictions of a recently proposed model on the joint motion of curved and faceted boundary segments. The results are compared to data published for a 30° boundary. It is shown that the observed dynamic facet length corresponds to a maximum dissipation rate of free energy.
Ultrasonic study of short-range hydrogen ordering in Pd-hydride
Authors: Safarik D. J. , Schwarz R. B.
Published: May 2008

We used resonant ultrasound spectroscopy to measure the three independent elastic constants of PdH0.71 and PdH0.65 in the temperature range 1.4 K < T < 296 K. Measurements were performed as the crystals were rapidly cooled (∼10 K min− 1) and then slowly heated (∼0.1 K min− 1). During slow heating, the temperature dependence of the shear modulus C′ = (C11 – C12)/2 shows a small peak at ∼55 K, but this peak is absent during fast cooling. We associate the peak with the so-called “50 K anomaly” in palladium hydride. In contrast, the other shear modulus, C44, shows no peak during slow heating. We propose that the 50 K anomaly observed in the elastic constants, and in other thermodynamic and transport properties of Pd-hydride, is a kinetic effect arising from changes in the hydrogen atom short-range order as the alloy is heated.
eCorner: Propulsion by Hub Motors
Authors: Gombert B.
Published: May 2008

The requirements of motor vehicles are constantly increasing, both in terms of consumption and emissions, as well as comfort and safety. Through the integration of sensors, the replacement and the intelligent processing of data and information, a lot of driver assistance functions have emerged. The evolving trend towards intelligent driver assistance systems and self autonomous driving is feasible nowadays. The vision of the car of the future could lie in the realisation of the eCorner. Here, every one of the four wheels can be controlled, steered and braked individually, through "by‐wire" commands.
A Simple Template‐Free Strategy to Synthesize Nanoporous Manganese and Nickel Oxides with Narrow Pore Size Distribution, and Their Electrochemical Properties
Authors: Yu Chichao , Zhang Lingxia , Shi Jianlin , Zhao Jinjin , Gao Jianhua , Yan Dongsheng
Published: May 2008

A facile method has been developed to synthesize nanoporous manganese and nickel oxides with polyhedron particle morphologies, high surface areas and narrow pore distributions by controlled thermal decomposition of the oxalate precursors. This method can be extended to using other kinds of salt precursors to prepare a series of nanoporous metal oxides. The heating rate, calcination temperature and controlled particle size of the oxalate precursors are important factors to get well‐defined pore structures. XRD, TG‐DTA, TEM, SEM, XPS, wet chemical titration and N2 sorption isotherm techniques are employed for morphology and structure characterizations. High surface area microporous manganese oxide (283 m2 g−1) and mesoporous nickel oxide (179 m2 g−1) with narrow pore distribution at around 1.0 nm and 6.0 nm, respectively, are obtained. Especially, we can tune the pore size of manganese oxides from microscope to mesoscope by controlling the thermal procedure. Electrochemical properties of manganese and nickel oxides are studied by cyclic voltammetry measurements in a mild aqueous electrolyte, which shows a high specific capacitance of 309 F g−1 of microporous manganese oxide and a moderately high specific capacitance of 165 F g−1 of mesoporous NiO due to their nanoporous structure, presenting the promising candidates for super capacitors (SC).
Temperature‐Induced Size‐Control of Bioactive Surface Patterns
Authors: Ionov Leonid , Synytska Alla , Diez Stefan
Published: May 2008

We present a novel method to produce bioactive surface patterns whose size can be changed in response to a variation of the environmental conditions, rather than local treatment. Our approach is based on the structured surface‐immobilization of thermoresponsive poly(N‐isopropylacrylamide) (PNIPAM) polymer chains with different transition temperatures. We experimentally demonstrate how the size of an area in which a particular polymer is collapsed or swollen can be controlled by ambient temperature. We show the temperature‐induced size‐control of a bioactive surface pattern by embedding functional motor proteins into the switchable polymer layers.
The role of steroid hormones in the NF1 phenotype: Focus on pregnancy
Authors: Roth Therese M. , Petty Elizabeth M. , Barald Kate F.
Published: May 2008

The Neurofibromatosis Type 1 (NF1) gene functions as a tumor suppressor gene. Loss of its protein, neurofibromin, in the autosomal dominant disorder NF1 is associated with peripheral nervous system tumors, particularly neurofibromas, benign lesions in which the major cell type is the Schwann Cell (SC). Benign and malignant human tumors found in NF1 patients are heterogeneous with respect to their cellular composition. The number and size of neurofibromas in NF1 patients has been shown to increase during pregnancy, with, in some cases, post‐partum regression, which suggests hormonal involvement in this increase. However, in this review, we consider evidence from the literature that both direct hormonal influence on tumor growth and on angiogenesis may contribute to these effects. © 2008 Wiley‐Liss, Inc.
The effects of diabetes and aminoguanidine treatment on endothelial function in a primate model of type 1 diabetes
Authors: Brooks Belinda A. , Heffernan Scott , Thomson Sally , McLennan Susan V. , Twigg Stephen M. , Yue Dennis K.
Published: May 2008

Abnormalities of endothelial function have been demonstrated in diabetes and are thought to play a role in the pathogenesis of diabetic complications. The aims of this study were to determine whether aminoguanidine, an inhibitor of glycation, can prevent endothelial and microcirculation abnormalities in a primate model of type 1 diabetes. Male baboons (Papio hamadryas) were assigned to one of the four groups: control, diabetes, control treated with aminoguanidine or diabetes treated with aminoguanidine. Diabetes was induced by streptozocin (60 mg/kg) and treated with once daily injection of insulin. Aminoguanidine was given subcutaneously (10 mg/kg), once a day. Diabetic animals had a mean duration of diabetes of 8.9±3.4 years and HbA1c of 8.9±1.1%. Microvascular function was measured by laser Doppler velocimetry, with examination of endothelium‐dependent increase in skin blood flow (SkBF) following iontophoresis of acetylcholine (ACh) and endothelium‐independent increase in SkBF in response to the nitric oxide (NO) donor sodium nitroprusside (SNP). Multiple regression analysis identified diabetes (P=0.049) and aminioguanidine treatment (P=0.026) as significant determinants of ACh response. The diabetic baboons treated with aminoguanidine had less Ach‐mediated SkBF response compared with controls (1.39±0.32 vs. 2.26±0.61, F=3.3, P=0.04), but there was no difference between groups in SkBF response to SNP. We conclude that endothelial dysfunction can be demonstrated in this primate model of type 1 diabetes at a stage when overt diabetic complications are not present. This occurred in the absence of insulin resistance or significant hypercholesterolemia. Administration of aminoguanidine from the onset of diabetes was not able to prevent this abnormality and in fact aggravated the endothelial response. Effects of aminoguanidine on NO synthase may contribute to this phenomenon. Am. J. Primatol. 70:796–802, 2008. © 2008 Wiley‐Liss, Inc.