Effects of herbicides diuron and atrazine on corals of the Great Barrier Reef, Australia

In response to recent reports of contamination of the nearshore marine environment along the Queensland coast by herbicides (including areas inside the Great Barrier Reef Marine Park), an ecotoxicological assessment was conducted of the impact of the herbicides diuron and atrazine on scleractinian corals. Pulse-amplitude modulated (PAM) chlorophyll fluorescence techniques were used to assess the herbicide effects on the symbiotic dinoflagellates within the tissues (in hospite) of 4 species of coral (Acropora formosa, Montipora digitata, Porites cylindrica, Seriatopora hystrix) in static toxicity tests, and in freshly isolated symbiotic dinoflagellates from Stylophora pistillata. Using change in the effective quantum yield (DeltaF/F-m') as an effect criterion, diuron (no observable effect concentration, NOEC = 0.3 mug 1(-1); lowest observable effect concentration, LOEC = 1 mug 1(-1); median effective concentration, EC50 4 to 6 mug 1(-1)) was found to be more toxic than atrazine (NOEC = 1 mug 1(-1), LOEC = 3 mug 1(-1), EC50 40 to 90 mug 1(-1)) in short-term (10 h) toxicity tests. In the tests with isolated algae, significant reductions in DeltaF/F-m' were recorded as low as 0.25 mug 1(-1) diuron (LOEC, EC50 = 5 mug 1(-1)). Time-course experiments indicated that the effects of diuron were rapid and reversible. At 10 mug 1(-1) diuron, DeltaF/F-m' was reduced by 25% in 20 to 30 min, and by 50% in 60 to 90 min. Recovery of DeltaF/F-m' in corals exposed to 10 mug 1(-1) diuron and then transferred to running seawater was slower, returning to within 10% of control values inside 1 to 7 h. The effect of a reduction in salinity (35 to 27%) on diuron toxicity (at 1 and 3 mug 1(-1) diuron) was tested to examine the potential consequences of contaminated coastal flood plumes inundating inshore reefs. DeltaF/F-m' was reduced in the diuron-exposed corals, but there was no significant interaction between diuron and reduced salinity seawater within the 10 h duration of the test. Exposure to higher (100 and 1000 mug 1(-1)) diuron concentrations for 96 h caused a reduction in DeltaF/F-m' the ratio variable to maximal fluorescence (F,1F.), significant loss of symbiotic dinoflagellates and pronounced tissue retraction, causing the corals to pale or bleach. The significance of the results in relation to diuron contamination of the coastal marine environment from terrestrial sources (mainly agricultural) and marine sources (antifouling paints) are discussed.

Asymmetric contribution of α and β subunits to the activation of αβ heteromeric glycine receptors

This study investigated the role of beta subunits in the activation of alphabeta heteromeric glycine receptor (GlyR) chloride channels recombinantly expressed in HEK293 cells. The approach involved incorporating mutations into corresponding positions in alpha and beta subunits and comparing their effects on receptor function. Although cysteine-substitution mutations to residues in the N-terminal half of the alpha subunit M2-M3 loop dramatically impaired the gating efficacy, the same mutations exerted little effect when incorporated into corresponding positions of the beta subunit. Furthermore, although the alpha subunit M2-M3 loop cysteines were modified by a cysteine-specific reagent, the corresponding beta subunit cysteines showed no evidence of reactivity. These observations suggest structural or functional differences between alpha and beta subunit M2-M3 loops. In addition, a threonine-->leucine mutation at the 9' position in the beta subunit M2 pore-lining domain dramatically increased the glycine sensitivity. By analogy with the effects of the same mutation in other ligand-gated ion channels, it was concluded that the mutation affected the GlyR activation mechanism. This supports the idea that the GlyR beta subunit is involved in receptor gating. In conclusion, this study demonstrates that beta subunits contribute to the activation of the GlyR, but that their involvement in this process is significantly different to that of the alpha subunit.

Conformational changes in SP-B as a function of surface pressure

X-ray reflectivity of bovine and sheep surfactant-associated protein B (SP-B) monolayers is used in conjunction with pressure-area isotherms and protein models to suggest that the protein undergoes changes in its tertiary structure at the air/water interface under the influence of surface pressure, indicating the likely importance of such changes to the phenomena of protein squeeze out as well as lipid exchange between the air-water interface and subphase structures. We describe an algorithm based on the well-established box- or layer-models that greatly assists the fitting of such unknown scattering-length density profiles, and which takes the available instrumental resolution into account. Scattering-length density profiles from neutron reflectivity of bovine SP-B monolayers on aqueous subphases are shown to be consistent with the exchange of a large number of labile protons as well as the inclusion of a significant amount of water, which is partly squeezed out of the protein monolayer at elevated surface pressures.

Cortex, cognition and the cell: New insights into the pyramidal neuron and prefrontal function

Arguably the most complex conical functions are seated in human cognition, the how and why of which have been debated for centuries by theologians, philosophers and scientists alike. In his best-selling book, An Astonishing Hypothesis: A Scientific Search for the Soul, Francis Crick refined the view that these qualities are determined solely by cortical cells and circuitry. Put simply, cognition is nothing more, or less, than a biological function. Accepting this to be the case, it should be possible to identify the mechanisms that subserve cognitive processing. Since the pioneering studies of Lorent de No and Hebb, and the more recent studies of Fuster, Miller and Goldman-Rakic, to mention but a few, much attention has been focused on the role of persistent neural activity in cognitive processes. Application of modern technologies and modelling techniques has led to new hypotheses about the mechanisms of persistent activity. Here I focus on how regional variations in the pyramidal cell phenotype may determine the complexity of cortical circuitry and, in turn, influence neural activity. Data obtained from thousands of individually injected pyramidal cells in sensory, motor, association and executive cortex reveal marked differences in the numbers of putative excitatory inputs received by these cells. Pyramidal cells in prefrontal cortex have, on average, up to 23 times more dendritic spines than those in the primary visual area. I propose that without these specializations in the structure of pyramidal cells, and the circuits they form, human cognitive processing would not have evolved to its present state. I also present data from both New World and Old World monkeys that show varying degrees of complexity in the pyramidal cell phenotype in their prefrontal cortices, suggesting that cortical circuitry and, thus, cognitive styles are evolving independently in different species.

Purification of post-translationally modified proteins from bacteria: homologous expression and purification of histidine-tagged pilin from Neisseria meningitidis

Until recently, glycosylation of proteins in prokaryotes was regarded as uncommon and thought to be limited to special cases such as S-layer proteins and some archeal outer membrane proteins. Now, there are an increasing number of reports of bacterial proteins that are glycosylated. Pilin of pathogenic Neisseria is one of the best characterised post-translation ally modified bacterial proteins, with four different types of modifications reported, including a novel glycosylation. Pilin monomers assemble to form pilus fibres, which are long protein filaments that protrude from the surface of bacterial cells and are key virulence factors. To aid in the investigation of these modifications, pure pilin is required. A number of pilin purification methods have been published, but none are appropriate for the routine purification of pilin from many different isolates. This study describes a novel, rapid, and simple method of pilin purification from Neisseria meningitidis C311#3, which facilitates the production of consistent quantities of pure, native pilin. A 6 x histidine tag was fused to the C-terminus of the pilin subunit structural gene, pilE, via homologous recombination placing the 6 x histidine-tagged allele in the chromosome of N. meningitidis C311#3. Pilin was purified under non-denaturing conditions via a two-step process using immobilised metal affinity chromatography (IMAC), followed by dye affinity chromatography. Analysis of the purified pilin confirmed that it retained both of the post-translational modifications examined. This novel approach may prove to be a generally applicable method for purification and analysis of post-translationally modified proteins in bacteria. (C) 2003 Elsevier Science (USA). All rights reserved.

Modified logit life table system: Principles, empirical validation, and application

Despite its widespread use, the Coale-Demeny model life table system does not capture the extensive variation in age-specific mortality patterns observed in contemporary populations, particularly those of the countries of Eastern Europe and populations affected by HIV/AIDS. Although relational mortality models, such as the Brass logit system, can identify these variations, these models show systematic bias in their predictive ability as mortality levels depart from the standard. We propose a modification of the two-parameter Brass relational model. The modified model incorporates two additional age-specific correction factors (gamma(x), and theta(x)) based on mortality levels among children and adults, relative to the standard. Tests of predictive validity show deviations in age-specific mortality rates predicted by the proposed system to be 30-50 per cent lower than those predicted by the Coale-Demeny system and 15-40 per cent lower than those predicted using the original Brass system. The modified logit system is a two-parameter system, parameterized using values of l(5) and l(60).

Sistema de Controle log??stico de Medicamentos Antirretrovirais (SICLOM)

O Sistema de Controle Log??stico de Medicamentos Antirretrovirais (Siclom) ?? uma ferramenta criada com o objetivo de gerenciamento log??stico dos medicamentos antirretrovirais (ARV) e de aprimoramento da qualifica????o da dispensa????o. Esse sistema permite que o departamento de DST, Aids e Hepatites Virais, secretarias estaduais e municipais de Sa??de mantenham-se atualizados em rela????o ao fornecimento, dispensa????o de medicamentos aos pacientes em tratamento conforme as recomenda????es existentes no Consenso Terap??utico Brasileiro, al??m do controle dos estoques de cada medicamento nas v??rias regi??es do pa??s. As informa????es de consumo e estoques s??o fundamentais para que o adequado suprimento aos estados ocorra evitando, assim, a ruptura dos estoques locais e preju??zo no atendimento aos pacientes. Atualmente utilizam o sistema 670 unidades dispensadoras de medicamentos, distribu??das em todo o Brasil; 27 coordena????es estaduais de DST/Aids; 61 almoxarifados; e 936 maternidades

Utiliza????o do QFD: Quality Function Deployment como ferramenta de planejamento

A utiliza????o da matriz do QFD (em portugu??s, Desdobramento da Fun????o Qualidade) como entrada para o planejamento estrat??gico regional solidificou o entendimento da Diretoria Regional sobre as expectativas dos clientes ante seus principais processos, avaliados por meio de pesquisa externa realizada bianualmente. Direcionou as a????es a serem tomadas por meio da prioriza????o, da tradu????o e do desdobramento dos requisitos mais importantes para os clientes em todos os n??veis dos processos, alinhando essas a????es com as estrat??gias, a pol??tica da qualidade e o or??amento. Da mesma forma, serviu para estabelecer metas globais de satisfa????o por segmento, de forma mais estruturada, sistematizando a avalia????o dos resultados e focando sempre a satisfa????o dos clientes cujos resultados j?? se comprovaram: ??ndice de 8,6 em 2000 para 9,2 em 2004

Log??stica de distribui????o e entrega dos objetos do Programa Nacional do Livro Did??tico (PNLD)

O Programa Nacional do Livro Did??tico ??? PNLD, administrado pelo Fundo Nacional de Desenvolvimento da Educa????o ??? FNDE, utiliza, desde 1994, os servi??os da Empresa Brasileira de Correios e Tel??grafos - ECT, para levar ??s escolas p??blicas mais de uma centena de milh??es de livros did??ticos. V??rios eram os problemas a serem resolvidos. Antes de a ECT assumir os servi??os, somente 25% dos livros eram entregues antes do in??cio do ano letivo e o restante entregue durante ano, prejudicando de uma sobre maneira, n??o s?? alunos e professores, mas todo o planejamento de ensino. A aus??ncia de um controle efetivo da entrega dos livros, aliado ao endere??amento incorreto, gerava um de alto ??ndice de reclama????o quanto ao n??o recebimento dos objetos. Com as a????es descritas nesse relato, foi poss??vel aumentar o n??mero de crian??as/adolescentes estudantes de escolas p??blicas, com cobertura de todos os munic??pios brasileiros, os quais s??o na realidade os grandes clientes de todo o processo. Certamente que o sucesso da opera????o envolve a FNDE e a ECT, sendo que nesta ??ltima ?? imprescind??vel a perfeita sintonia entre todas as ??reas

Cataloga????o, uma ferramenta para a log??stica

A cataloga????o consiste numa ferramenta de aplica????o nos ??rg??os p??blicos federais, que permite o uso de linguagem ??nica de identifica????o de materiais, de forma que possa ser entendida e manipulada por qualquer sistema, desde que este conhe??a as regras da linguagem. Essa ferramenta, entre outras utilidades, possibilita a execu????o de boa gest??o de material, por meio da intera????o de todos os ??rg??os do governo, permitindo o apoio m??tuo entre eles, e da nacionaliza????o de itens importados, contribuindo para a redu????o de nossa depend??ncia externa e para o incentivo ?? ind??stria nacional. A cataloga????o possibilita, ainda, a descoberta de utiliza????o de itens comuns de material, a perfeita identifica????o de um item, a otimiza????o do planejamento or??ament??rio e a redu????o do custo log??stico dos ??rg??os por melhor compra, armazenagem, aplica????o, destina????o de excessos e otimiza????o de estoques

Sistema de avalia????o log??stica variada

As normas que regem a gratifica????o de Desempenho e Produtividade ??? GDP ??? recebidas pelos servidores da Carreira de Finan??as e Controle da Secretaria Federal de Controle, estabelecem limites pares ao n??mero de servidores que podem ser avaliados com notas superiores a 8. Essa limita????o est?? fixada em 20% para as notas na faixa de 8 a 9 e 10% para as notas acima de 9. O fato da Secretaria Federal de Controle possuir muitas unidades, inviabilizou a escolha dos servidores que, devido ao seu melhor desempenho, mereceriam receber as notas mais altas. A solu????o deste e de outros problemas dele decorrentes foi a implementa????o do Sistema de Avalia????o Log??stica Variada ??? SALVA, que operacionaliza a distribui????o dos valores n??o inteiros da gratifica????o de desempenho e produtividade com exatid??o e igualdade

M??dulo 1 - a import??ncia e a necessidade da lei de licita????es: curso legisla????o aplicada ?? log??stica de suprimentos lei 8.666/93, preg??o e registro de pre??os

Este documento trata de: aspectos conceituais da lei: finalidade, import??ncia e hierarquia da lei.; no????es gerais da lei de licita????es - Lei n?? 8.666/93; tipos de licita????o:menor pre??o, melhor t??cnica, t??cnica e pre??o e maior lance ou oferta; modalidades de licita????o: concorr??ncia, tomada de pre??os, convite, concurso e leil??o; exce????es ?? obrigatoriedade de licita????o: dispensa e inexigibilidade; regime de execu????o indireta; comiss??o de licita????o; etapas do processo licitat??rio: edital, procedimentos/documentos do certame, registro cadastral, habilita????o dos interessados, julgamento e encerramento; preg??o; registro de pre??os

M??dulo 2 - a lei de licita????es: curso legisla????o aplicada ?? log??stica de suprimentos lei 8.666/93, preg??o e registro de pre??os

Este documento trata de: aspectos conceituais da lei: finalidade, import??ncia e hierarquia da lei.; no????es gerais da lei de licita????es - Lei n?? 8.666/93; tipos de licita????o:menor pre??o, melhor t??cnica, t??cnica e pre??o e maior lance ou oferta; modalidades de licita????o: concorr??ncia, tomada de pre??os, convite, concurso e leil??o; exce????es ?? obrigatoriedade de licita????o: dispensa e inexigibilidade; regime de execu????o indireta; comiss??o de licita????o; etapas do processo licitat??rio: edital, procedimentos/documentos do certame, registro cadastral, habilita????o dos interessados, julgamento e encerramento; preg??o; registro de pre??os

M??dulo 3 - tipos de licita????o: curso legisla????o aplicada ?? log??stica de suprimentos lei 8.666/93, preg??o e registro de pre??os

Este documento trata de: aspectos conceituais da lei: finalidade, import??ncia e hierarquia da lei.; no????es gerais da lei de licita????es - Lei n?? 8.666/93; tipos de licita????o:menor pre??o, melhor t??cnica, t??cnica e pre??o e maior lance ou oferta; modalidades de licita????o: concorr??ncia, tomada de pre??os, convite, concurso e leil??o; exce????es ?? obrigatoriedade de licita????o: dispensa e inexigibilidade; regime de execu????o indireta; comiss??o de licita????o; etapas do processo licitat??rio: edital, procedimentos/documentos do certame, registro cadastral, habilita????o dos interessados, julgamento e encerramento; preg??o; registro de pre??os

M??dulo 4 - modalidades de licita????o: curso legisla????o aplicada ?? log??stica de suprimentos lei 8.666/93, preg??o e registro de pre??os

Este documento trata de: aspectos conceituais da lei: finalidade, import??ncia e hierarquia da lei.; no????es gerais da lei de licita????es - Lei n?? 8.666/93; tipos de licita????o:menor pre??o, melhor t??cnica, t??cnica e pre??o e maior lance ou oferta; modalidades de licita????o: concorr??ncia, tomada de pre??os, convite, concurso e leil??o; exce????es ?? obrigatoriedade de licita????o: dispensa e inexigibilidade; regime de execu????o indireta; comiss??o de licita????o; etapas do processo licitat??rio: edital, procedimentos/documentos do certame, registro cadastral, habilita????o dos interessados, julgamento e encerramento; preg??o; registro de pre??os