Limitations to photosynthesis of lettuce grown under tropical conditions: alleviation by root-zone cooling

Aerial parts of lettuce plants were grown under natural tropical fluctuating ambient temperatures, but with their roots exposed to two different root-rone temperatures (RZTs): a constant 20 degreesC-RZT and a fluctuating ambient (A-) RZT from 23-40 degreesC, Plants grown at A-RZT showed lower photosynthetic CO2 assimilation (A), stomatal conductance (g(s)), midday leaf relative water content (RWC), and chlorophyll fluorescence ratio F-v/F-m than 20 degreesC-RZT plants on both sunny and cloudy days. Substantial midday depression of A and g(s) occurred on both sunny and cloudy days in both RZT treatments, although F-v/F-m did not vary diurnally on cloudy days. Reciprocal temperature transfer experiments investigated the occurrence and possible causes of stomatal and non-stomatal limitations of photosynthesis. For both temperature transfers, light-saturated stomatal conductance (g(s) (sat)) and photosynthetic CO2 assimilation (A(sat)) were highly correlated with each other and with midday RWC, suggesting that A was limited by water stress-mediated stomatal closure, However, prolonged growth at A-RZT reduced light- and CO2-saturated photosynthetic O-2 evolution (P-max), indicating non-stomatal limitation of photosynthesis. Tight temporal coupling of leaf nitrogen content and P-max during both temperature transfers suggested that decreased nutrient status caused this non-stomatal limitation of photosynthesis.

Minimum acceptable standards for digital compression of a fetal ultrasound video-clip

If the Internet could be used as a method of transmitting ultrasound images taken in the field quickly and effectively, it would bring tertiary consultation to even extremely remote centres. The aim of the study was to evaluate the maximum degree of compression of fetal ultrasound video-recordings that would not compromise signal quality. A digital fetal ultrasound videorecording of 90 s was produced, resulting in a file size of 512 MByte. The file was compressed to 2, 5 and 10 MByte. The recordings were viewed by a panel of four experienced observers who were blinded to the compression ratio used. Using a simple seven-point scoring system, the observers rated the quality of the clip on 17 items. The maximum compression ratio that was considered clinically acceptable was found to be 1:50-1:100. This produced final file sizes of 5-10 MByte, corresponding to a screen size of 320 x 240 pixels, running at 15 frames/s. This study expands the possibilities for providing tertiary perinatal services to the wider community.

On-line analysis of froth surface in coal and mineral flotation using JKFrothCam

The personal computer revolution has resulted in the widespread availability of low-cost image analysis hardware. At the same time, new graphic file formats have made it possible to handle and display images at resolutions beyond the capability of the human eye. Consequently, there has been a significant research effort in recent years aimed at making use of these hardware and software technologies for flotation plant monitoring. Computer-based vision technology is now moving out of the research laboratory and into the plant to become a useful means of monitoring and controlling flotation performance at the cell level. This paper discusses the metallurgical parameters that influence surface froth appearance and examines the progress that has been made in image analysis of flotation froths. The texture spectrum and pixel tracing techniques developed at the Julius Kruttschnitt Mineral Research Centre are described in detail. The commercial implementation, JKFrothCam, is one of a number of froth image analysis systems now reaching maturity. In plants where it is installed, JKFrothCam has shown a number of performance benefits. Flotation runs more consistently, meeting product specifications while maintaining high recoveries. The system has also shown secondary benefits in that reagent costs have been significantly reduced as a result of improved flotation control. (C) 2002 Elsevier Science B.V. All rights reserved.

Copper transfer from the Cu(I) chaperone, CopZ, to the repressor, Zn(II)CopY: Metal coordination environments and protein interactions

Extracellular copper regulates the DNA binding activity of the CopY repressor of Enterococcus hirae and thereby controls expression of the copper homeostatic genes encoded by the cop operon. CopY has a CxCxxxxCxC metal binding motif. CopZ, a copper chaperone belonging to a family of metallochaperones characterized by a MxCxxC metal binding motif, transfers copper to CopY. The copper binding stoichiometries of CopZ and CopY were determined by in vitro metal reconstitutions. The stoichiometries were found to be one copper(l) per CopZ and two copper(l) per CopY monomer. X-ray absorption studies suggested a mixture of two- and three-coordinate copper in Cu(1)CopZ, but a purely three-coordinate copper coordination with a Cu-Cu interaction for Cu(1)(2)CopY. The latter coordination is consistent with the formation of a compact binuclear Cu(l)-thiolate core in the CxCxxxxCxC binding motif of CopY. Displacement of zinc, by copper. from CopY was monitored with 2,4-pyridylazoresorcinol. Two copper(l) ions were required to release the single zinc(II) ion bound per CopY monomer. The specificity of copper transfer between CopZ and CopY was dependent on electrostatic interactions. Relative copper binding affinities of the proteins were investigated using the chelator, diethyldithiocarbamic acid (DDC). These data suggest that CopY has a higher affinity for copper than CopZ. However, this affinity difference is not the sole factor in the copper exchange: a charge-based interaction between the two proteins is required for the transfer reaction to proceed. Gain-of-function mutation of a CopZ homologue demonstrated the necessity of four lysine residues on the chaperone for the interaction with CopY. Taken together, these results suggest a mechanism for copper exchange between CopZ and CopY.

Did they read Marx? Marx reception and social democratic party members in imperial Germany, 1890-1914

Did rank-and-file members of the German Social Democratic party before 1914 bother to read Marx? A number of studies of borrowing from trade union and other workers' libraries since the 1970s have indicated that workers who read Marx were rare, although this does not mean that workers' reading habits were not influenced by socialist ideas. However, for a broader understanding of the reception of Marx's writings among rank-and-file German socialists, it is necessary to consider not only books, but the pamphlet literature produced by the SPD in huge quantities, serialisations and other treatments in the party press, and oral communication. When the full range of sources is considered, the extent of the reception of Marx's writings, albeit often in very simplified forms, can be more fully appreciated.

Remitting behaviour of Nepalese rural-to-urban migrants: Implications for theory and policy

This article uses data for Nepal to test contemporary hypotheses about the remitting behaviour and associated motives of rural-to-urban migrants and to consider the likely impact of such remittances on rural development. Possibilities for inheritance, degree of family attachment, likelihood of eventual return to place of origin and family investment in the education of the migrants are found to be significant influences on levels of remittances by Nepalese migrants. However, in Nepal, remittances do not seem to result in long-term capital investment in rural areas and so may not promote long-term development of these areas.

Geography's emerging cross-disciplinary links: Process, causes, outcomes and challenges

In Australian universities the discipline of Geography has been the pace-setter in forging cross-disciplinary links to create multidisciplinary departments and schools, well ahead of other disciplines in humanities, social sciences and sciences, and also to a greater extent than in comparable overseas university systems. Details on all cross-disciplinary links and on immediate outcomes have been obtained by surveys of all heads of departments/schools with undergraduate Geography programs. These programs have traced their own distinctive trajectories, with ramifying links to cognate fields of enquiry, achieved through mergers, transfers, internal initiatives and, more recently, faculty-wide restructuring to create supradisciplinary schools. Geography's `exceptionalism' has proved short-lived. Disciplinary flux is now extending more widely within Australian universities, driven by a variety of internal and external forces, including: intellectual questioning and new ways of constituting knowledge; technological change and the information revolution; the growth of instrumentalism and credentialism, and managerialism and entre-preneurial imperatives; reinforced by a powerful budgetary squeeze. Geographers are proving highly adaptive in pursuit of cross-disciplinary connections, offering analytical tools and selected disciplinary insights useful to non-geographers. However, this may be at cost to undergraduate programs focussing on Geography's intellectual core. Whereas formerly Geography had high reproductive capacity but low instrumental value it may now be in a phase of enhanced utility but perilously low reproductive capacity.

Sustained high levels of foliar herbivory of the mangrove Rhizophora stylosa by a moth larva Doratifera stenosa (Limacodidae) in north-eastern Australia

The moth larva, Doratifera stenosa (Lepidoptera: Limacodidae), was observed feeding voraciously in great numbers on mature leaves of Rhizophora stylosa in mangroves at Port Curtis in Central Queensland, NE Australia. This behaviour was considered unusual since mangroves, and the Rhizophora species in particular, reportedly harbour few herbivores and have relatively low levels of herbivory, less than 10%. During a two year period (1996-1998), larvae were observed consuming around 30-40% of leaves in the canopy each year, and the mangroves appeared able to sustain these high levels of herbivory. The impact on trees was assessed in conjunction with a study of the herbivore, its behaviour and life history, in an attempt to explain the occurrence. Larvae were 1-2 cm in length, bright green and gregarious, with numerous small, stinging hairs along their upper bodies. Feeding was in small cohort groups of 5-70 individuals that broke up immediately prior to each moult after which they regrouped in much larger numbers of mixed cohorts to form single-file processions across branches, stems and prop roots. In this way, they moved to neighbouring trees with less affected foliage. One of the outstanding characteristics of this herbivore was its ability to desist from killing host trees although it appeared quite capable of doing so had it remained on individual trees. By moving from tree to tree, the herbivore was able to heavily crop Rhizophora foliage in an apparently sustainable manner. These findings demonstrate the role and importance of foliar herbivory in severely affected forests and how such instances best not be ignored or treated as curiosities in future assessments of herbivory and forest turnover in mangrove ecosystems.

Wall mediated transport in confined spaces: Exact theory for low density

We present a theory for the transport of molecules adsorbed in slit and cylindrical nanopores at low density, considering the axial momentum gain of molecules oscillating between diffuse wall reflections. Good agreement with molecular dynamics simulations is obtained over a wide range of pore sizes, including the regime of single-file diffusion where fluid-fluid interactions are shown to have a negligible effect on the collective transport coefficient. We show that dispersive fluid-wall interactions considerably attenuate transport compared to classical hard sphere theory.

Reflex??es sobre a emerg??ncia da participa????o social na agenda das pol??ticas p??blicas: desafios ?? forma de organiza????o burocr??tica do Estado

No Brasil, a Constitui????o de 1988 institucionalizou a participa????o social em conselhos a serem compostos por representantes de diferentes setores da sociedade, do Estado e, em alguns casos, dos trabalhadores. A partir dos anos 2000, a realiza????o de confer??ncias passou a ser disseminada como mais uma forma de participa????o, que auxilia no mapeamento das demandas e na constru????o de consensos entre os movimentos sociais nos momentos que antecedem a formula????o de pol??ticas pelo poder executivo. Seja qual for a forma de participa????o social institucionalizada, regras e procedimentos regulamentados pelo Estado regem as intera????es com a Sociedade. Esse ensaio se dedica a problematizar a efetividade dos espa??os e mecanismos do ponto de vista do processamento de pol??ticas p??blicas dentro do aparato burocr??tico a partir de conceitos derivados das teorias de complexidade, participa????o e burocracia com a inten????o de contribuir para o debate sobre o aperfei??oamento desse campo

Redes de capacita????o: a experi??ncia da Escola de Governo e das universidades p??blicas do estado do Paran??

No Estado do Paran??, o movimento de forma????o e desenvolvimento dos servidores p??blicos ?? difundido a partir da cria????o da Escola de Governo, em 2004. Este artigo tem como objetivo apresentar a experi??ncia da constru????o de uma rede de capacita????o em pol??ticas p??blicas voltada ?? qualifica????o dos quadros de carreira de n??vel superior, analisando os desdobramentos e os fatores limitadores da rede. Apresenta a rede de capacita????o constru??da em parceria entre a Escola de Governo do Paran?? e seis Institui????es P??blicas de Ensino Superior (Universidade Estadual de Londrina, Universidade Estadual de Maring??, Universidade Estadual de Ponta Grossa, Universidade do Centro-Oeste do Paran??, Universidade do Oeste do Paran??, e a Universidade Federal do Paran??). A metodologia utilizada neste paper ?? o estudo de caso que relatar?? a constru????o da rede de capacita????o com as seguintes etapas: identifica????o dos diversos atores e a institui????o de c??mara t??cnica para a discuss??o e formata????o de curso de especializa????o que atendesse ??s necessidades e especificidades da Escola de Governo do Paran??; o processo seletivo; o desenvolvimento do Curso de P??s-Gradua????o, pelas Universidades p??blicas parceiras; o acompanhamento do Curso pela equipe da Escola de Governo do Paran??; os projetos de interven????o feitos pelos alunos; a dissemina????o do conhecimento produzido. O ponto alto do trabalho em rede se deu com as discuss??es do Curso na C??mara T??cnica: tem??tica do curso, fontes de recursos, projeto do curso, o p??blico-alvo, o ambiente de aprendizagem, o acesso ?? tecnologia, o suporte acad??mico e administrativo, o acompanhamento e avalia????o, a difus??o/dissemina????o do conhecimento. Dos resultados obtidos a partir da intera????o entre os integrantes da rede destacam-se: 19 turmas de um curso de P??s-Gradua????o em Formula????o e Gest??o de Pol??ticas P??blicas num total de 572 especialistas, al??m da realiza????o de um Semin??rio de Gest??o P??blica no Paran??, da cria????o do Reposit??rio Institucional SabeRES em Gest??o P??blica de acesso livre e da publica????o de livros sobre Gest??o de Pol??ticas P??blicas no Paran??, contendo artigos publicados pelos alunos sobre tem??ticas relacionadas ?? gest??o p??blica. Com isso, o Estado do Paran?? iniciou um processo de constru????o de saberes em gest??o p??blica a partir da reflex??o de suas pr??prias viv??ncias e experi??ncias, e de uma rela????o harmoniosa e inovadora entre produtores de saberes ??? a institui????o acad??mica e a administra????o p??blica ??? os quais criaram condi????es para a constru????o do conhecimento, o que n??o teria sido poss??vel de maneira isolada. Essa rede de conhecimento em pol??ticas p??blicas, por ter sido coletivamente constru??da, revelou que mais importante que o conhecimento em si e o processo da sua constru????o, foi a transposi????o desses resultados para a realidade n??o apenas dos produtores desse conhecimento, mas para todos os que atuam e s??o beneficiados pela gest??o p??blica

Federalismo fiscal, atribui????es fiscais constitucionais e equaliza????o regional: EUA, Alemanha e Brasil em perspectiva comparada

Este trabalho aborda aspectos institucional-constitucionais do sistema federal brasileiro com vistas a tratar do problema da equaliza????o regional. O foco de an??lise desta investiga????o ser?? a articula????o entre as atribui????es fiscais constitucionais (incluindo a reparti????o das compet??ncias tribut??rias e as principais transfer??ncias correlatas) e a tarefa de equaliza????o regional no Brasil, a partir de uma perspectiva de estudo institucional comparado envolvendo Estados Unidos, Alemanha e Brasil.

Reforma do setor p??blico e participa????o sindical: o caso do sistema de pens??o italiano

O paper estuda o caso da recente reforma da Previd??ncia na It??lia, ilustrando a possibilidade de uma participa????o positiva dos sindicatos ??? tradicionalmente contr??rios ??s reformas ??? no processo de transforma????o do setor p??blico. Ap??s uma revis??o do sistema previdenci??rio italiano, altamente fragmentado e particularista na opini??o dos autores, e o apontamento de suas principais defici??ncias, o estudo concentra-se na an??lise de tr??s propostas de reforma ligadas aos governos de Amato (1992-93), Berlusconi (1994) e Dini (1995), respectivamente. O texto aborda tanto as propostas concretas de mudan??a, trazendo contribui????es sobre uma variedade consider??vel de medidas, seu impacto e aceita????o sociais e por categoria, como os objetivos visados e o processo pol??tico relacionado ?? sua discuss??o e tramita????o. Uma preocupa????o constante dos autores ?? a correla????o entre a postura e a participa????o dos sindicatos em mat??ria de reforma previdenci??ria, por um lado, e o avan??o das propostas governamentais, por outro. Segundo o estudo, a ampla participa????o da for??a sindical na negocia????o do projeto de reforma previdenci??ria do governo Dini representou um fator decisivo para sua aprova????o e implementa????o bem-sucedidas. Ao mesmo tempo, a delibera????o democr??tica para concilia????o de prefer??ncias e interesses (m??ltiplos no caso de assuntos norteados pela dicotomia bem comum/interesse particular) ??? objeto da ??ltima sess??o do estudo ??? ?? vista como uma forma de ampliar a participa????o sindical al??m das lideran??as, passando a incluir os rank-and-file trabalhadores, um procedimento que traz, igualmente, a for??a de uma decis??o majorit??ria. A an??lise da reforma da Previd??ncia italiana ?? ilustrada no paper com tabelas que trazem e comparam dados referentes ?? contribui????o previdenci??ria, ??s categorias de beneficiados e ??s diferentes propostas de reforma formuladas por sucessivos governos italianos.

Vantagens e desvantagens do preg??o na gest??o de compras no setor p??blico: o caso da Funasa/PB

O presente artigo ?? parte de um estudo explorat??rio cujo objetivo foi analisar as vantagens e desvantagens na aquisi????o de bens e servi??os por meio das modalidades de licita????o preg??o presencial e eletr??nico no servi??o p??blico. Para isso, foi realizado um estudo de caso na Funda????o Nacional de Sa??de da Para??ba. A parte da pesquisa divulgada neste artigo, al??m de uma s??ntese sobre o referencial te??rico, apresenta as caracter??sticas investigadas da modalidade de licita????o preg??o, comparando suas formas presencial e eletr??nica na institui????o estudada. Os resultados apontam aspectos relevantes quanto ??s quest??es: vantagens e desvantagens do preg??o eletr??nico em rela????o ao preg??o presencial e vice-versa; recursos para atendimento de despesas; planejamento anual da FUNASA/PB; economia de pre??o; economia e repasse de recursos para outras necessidades; prazos de fornecimento; treinamento e capacita????o de pessoal. Conclui a exposi????o destacando alguns pontos fortes e fracos do processo, sugerindo medidas a serem avaliadas no que tange a capacita????o de pessoal e planejamento anual na FUNASA/PB.

Intersetorialidade e transversalidade: a estrat??gia dos programas complementares do Bolsa Fam??lia

O artigo analisa a estrat??gia implementada em 2006 e 2007 pelo Programa Bolsa Fam??lia (PBF) para a articula????o de programas complementares ??s transfer??ncias condicionadas de renda, enfatizando sua contribui????o para o enfrentamento da desigualdade e da exclus??o social no Brasil, e apresenta resultados preliminares alcan??ados por alguns destes programas executados em n??vel federal. A articula????o de programas complementares possibilita o reconhecimento de necessidades de grupos populacionais em situa????o de risco social e promove a oferta de a????es espec??ficas para as suas necessidades, para uma inclus??o cidad?? diferenciada. A estrat??gia implementada em 2006 e 2007 foi caracterizada pela intersetorialidade e transversalidade e a cria????o de um espa??o prop??cio para o desenvolvimento de inova????es no campo das pol??ticas sociais. Apesar do car??ter recente dos programas complementares e das dificuldades de monitoramento, os resultados obtidos em programas federais e o comprometimento dos governos municipais na articula????o de programas municipais demonstram que essa pode ser uma op????o na agenda das pol??ticas sociais dos tr??s n??veis de governo no Brasil.