841 resultados para Clutch Pedal Linkages.


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In the context of the Ghanaian government’s objective of structural transformation with an emphasis on manufacturing, this paper provides a case study of economic transformation in Ghana, exploring patterns of growth, sector transformation, and agglomeration. We document and examine why, despite impressive growth and poverty reduction figures, Ghana’s economy has exhibited less transformation than might be expected for a country that has recently achieved middle-income status. Ghana’s reduced share of agriculture in the economy, unlike many successfully transformed countries in Asia and Latin America, has been filled by services, while manufacturing has stagnated and even declined. Likely causes include weak transformation of the agricultural sector and therefore little development of agro-processing, the emergence of “consumption cities” and consumption-driven growth, upward pressure on the exchange rate, weak production linkages, and a poor environment for private-sector-led manufacturing.

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It is argued that existing polar prediction systems do not yet meet users’ needs; and possible ways forward in advancing prediction capacity in polar regions and beyond are outlined. The polar regions have been attracting more and more attention in recent years, fuelled by the perceptible impacts of anthropogenic climate change. Polar climate change provides new opportunities, such as shorter shipping routes between Europe and East Asia, but also new risks such as the potential for industrial accidents or emergencies in ice-covered seas. Here, it is argued that environmental prediction systems for the polar regions are less developed than elsewhere. There are many reasons for this situation, including the polar regions being (historically) lower priority, with less in situ observations, and with numerous local physical processes that are less well-represented by models. By contrasting the relative importance of different physical processes in polar and lower latitudes, the need for a dedicated polar prediction effort is illustrated. Research priorities are identified that will help to advance environmental polar prediction capabilities. Examples include an improvement of the polar observing system; the use of coupled atmosphere-sea ice-ocean models, even for short-term prediction; and insight into polar-lower latitude linkages and their role for forecasting. Given the enormity of some of the challenges ahead, in a harsh and remote environment such as the polar regions, it is argued that rapid progress will only be possible with a coordinated international effort. More specifically, it is proposed to hold a Year of Polar Prediction (YOPP) from mid-2017 to mid-2019 in which the international research and operational forecasting community will work together with stakeholders in a period of intensive observing, modelling, prediction, verification, user-engagement and educational activities.

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This study tests predictions of the hypothesis of evolution of paternal care via sexual selection by using the Neotropical harvestman Pseudopucrolia sp. as the model organism. Females use natural cavities in roadside banks as nesting sites, which are defended by males against other males. Females leave the nests after oviposition, and all postzygotic parental care is accomplished by males, which protect the eggs and nymphs from predators. We provided artificial mud nests to individuals in the laboratory and conducted observations on the reproduction of the species. Male reproductive success was directly related to nest ownership time: the longer a male held a nest, the higher his chances of obtaining copulations. All males that succeeded in mating and obtaining one clutch eventually mated with additional females that added eggs to the clutch. Thus, desirable males were not limited to monogamy by paternal care. Experimental manipulations demonstrated that guarding males were more attractive to females than were nonguarding males and also that males guarded unrelated eggs. Finally, we found that females and nonguarding males spent more time foraging than guarding males. We use our data to contrast hypotheses on the origin and maintenance of paternal care and to provide a critical assessment of the hypothesis of the evolution of paternal care via sexual selection. (C) 2009 The Association for the Study of Animal Behaviour. Published by Elsevier Ltd. All rights reserved.

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It is known that large fragment sizes and high connectivity levels are key components for maintaining species in fragments; however, their relative effects are poorly understood, especially in tropical areas. In order to test these effects, we built models for explaining understory birds occurrence in a fragmented Atlantic Rain Forest landscape with intermediate habitat cover (3%). Data from over 9000 mist-net hours from 17 fragments differing in size (2-175 ha) and connectivity (considering corridor linkages and distance to nearby fragments) were ranked under a model selection approach. A total 1293 individuals of 62 species were recorded. Species richness, abundance and compositional variation were mainly affected by connectivity indices that consider the capacity of species to use corridors and/or to cross short distances up to 30 m through the matrix. Bird functional groups were differently affected by area and connectivity: while terrestrial insectivores, omnivores and frugivores were affected by both area and connectivity, the other groups (understory insectivores, nectarivores, and others) were affected only by connectivity. In the studied landscape, well connected fragments can sustain an elevated number of species and individuals. Connectivity gives the opportunity for individuals to use multiple fragments, reducing the influence of fragment size. While preserving large fragments is a conservation target worldwide and should continue to be, our results indicated that connectivity between fragments can enhance the area functionally connected and is beneficial to all functional groups and therefore should be a conservation priority. (C) 2008 Elsevier Ltd. All rights reserved.

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A relatively large amount of variation occurs in the reproductive ecology of tropical snakes, and this variation is generally regarded as being a consequence of seasonality in climate and prey availability. In some groups, even closely related species may differ in their reproductive ecology; however, in others it seems to be very conservative. Here we explore whether characters related to reproduction are phylogenetically constrained in a monophyletic group of snakes, the subfamily Dipsadinae, which ranges from Mexico to southern South America. We provide original data on reproduction for Leptodeira annulata, Imantodes cenchoa, and three species of Sibynomorphus from southern, southeastern and central Brazil, and data from literature for other species and populations of dipsadines. Follicular cycles were seasonal in Atractus reticulatus, Dipsa, albifrons, Hypsiglena torquata, Leptodeira maculata, L. punctata, Sibynomorphus spp. and Sibon sanniola from areas where climate is seasonal. In contrast, extended or continuous follicular cycles were recorded in Dipsas catesbyi, D. neivai, Imantodes cenchoa, Leptodeira annulata, and Ninia maculata from areas with seasonal and aseasonal climates. Testicular cycles also varied from seasonal (in H. torquiata) to continuous (in Dipsa,5 spp., Leptodeira annulata, L. maculata, N. maculata, and Sibynomorphus spp.). Most dipsadines are small (less than 500 rum SVL), and females attain sexual maturity with similar relative body size than males. Sexual dimorphism occurred in terms of SVL and tail length in most species, and clutch size tended to be small (less than five eggs). Combat behavior occurs in Imantodes cenchoa, which did not show sexual size dimorphism. Reproductive timing, for both females and males, varied among species but in general there were no differences between the tribes of Dipsadinae in most of the reproductive characteristics, such as mean body size, relative size at sexual maturity, sexual size and tail dimorphism, duration of vitellogenesis or egg-carrying in oviducts.

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We studied clutch size, hatching and fledging success, and time necessary for chick Kelp Gulls (Larus dominicanus) to leave the nest throughout two breeding seasons (2004 and 2005) on Guararitama Island, Sao Paulo, Brazil. We followed 93 nests in 2004 and 97 nests in 2005. The average (+/- SD) clutch size was 2.09 +/- 0.64 in 2004 and 1.93 +/- 0.59 in 2005. Hatching success was 74% in 2004 and 53% in 2005, and fledging success was 54% in 2004 and 58% in 2005. Chicks grew quickly, following the linear equation y(t) = 61g + 17.03g X age (in days), and began to fly at 40 days. Received 11 August 2008. Accepted 28 August 2009.

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Fluorescent AlPO(4) xerogels doped with different amounts of Rhodamine 6G (Rh6G) laser dye were prepared by a one-step sal-gel process. In addition, mesoporous AlPO(4) glasses obtained from undoped gels were loaded with different amounts of Rh6G by wet impregnation. Optical excitation and emission spectra of both series of samples show significant dependences on Rh6G concentration, revealing the influence of dye molecular aggregation. At comparable dye concentrations the aggregation effects are found to be significantly stronger in the gels than in the mesoporous glasses. This effect might be attributed to stronger interactions between the dye molecules and the glass matrix, resulting in more efficient dye dispersion in the latter. The interaction of Rh6G with the glassy AlPO(4) network has been probed by (27)Al and (31)P solid-state NMR techniques. New five- and six-coordinated aluminum environments have been observed and characterized by advanced solid-state NMR techniques probing (27)Al-(1)H and (27)Al-(31)P internuclear dipole couplings. The fractional area of these new Al sites is correlated with the combined fractional area of two new Q(3Al)((0)) and Q(2Al)((0)) phosphate species observed in the (31)P MAS NMR spectra. Based on this correlation as well as detailed composition dependent studies, we suggest that the new signals arise from the breakage of Al-O-P linkages associated with the insertion process. (C) 2010 Elsevier B.V. All rights reserved.

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The Activist Women's Voices Oral History Project, funded by AT&T, the Ford Foundation, the Ms. Foundation for Education and Communication, and the New York Council for Humanities, is committed to documenting the voices of unheralded activist women in community-based organizations in New York City. The archive was established in 1995 under the direction of Professors Joyce Gelb and Patricia Laurence with the aim of creating linkages between activist women in the New York City community and student and faculty researchers at the City University of New York.

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Objective Levodopa in presence of decarboxylase inhibitors is following two-compartment kinetics and its effect is typically modelled using sigmoid Emax models. Pharmacokinetic modelling of the absorption phase of oral distributions is problematic because of irregular gastric emptying. The purpose of this work was to identify and estimate a population pharmacokinetic- pharmacodynamic model for duodenal infusion of levodopa/carbidopa (Duodopa®) that can be used for in numero simulation of treatment strategies. Methods The modelling involved pooling data from two studies and fixing some parameters to values found in literature (Chan et al. J Pharmacokinet Pharmacodyn. 2005 Aug;32(3-4):307-31). The first study involved 12 patients on 3 occasions and is described in Nyholm et al. Clinical Neuropharmacology 2003:26:156-63. The second study, PEDAL, involved 3 patients on 2 occasions. A bolus dose (normal morning dose plus 50%) was given after a washout during night. Plasma samples and motor ratings (clinical assessment of motor function from video recordings on a treatment response scale between -3 and 3, where -3 represents severe parkinsonism and 3 represents severe dyskinesia.) were repeatedly collected until the clinical effect was back at baseline. At this point, the usual infusion rate was started and sampling continued for another two hours. Different structural absorption models and effect models were evaluated using the value of the objective function in the NONMEM package. Population mean parameter values, standard error of estimates (SE) and if possible, interindividual/interoccasion variability (IIV/IOV) were estimated. Results Our results indicate that Duodopa absorption can be modelled with an absorption compartment with an added bioavailability fraction and a lag time. The most successful effect model was of sigmoid Emax type with a steep Hill coefficient and an effect compartment delay. Estimated parameter values are presented in the table. Conclusions The absorption and effect models were reasonably successful in fitting observed data and can be used in simulation experiments.

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Understanding the genetic basis of traits involved in adaptation is a major challenge in evolutionary biology but remains poorly understood. Here, we use genome-wide association mapping using a custom 50 k single nucleotide polymorphism (SNP) array in a natural population of collared flycatchers to examine the genetic basis of clutch size, an important life-history trait in many animal species. We found evidence for an association on chromosome 18 where one SNP significant at the genome-wide level explained 3.9% of the phenotypic variance. We also detected two suggestive quantitative trait loci (QTLs) on chromosomes 9 and 26. Fitness differences among genotypes were generally weak and not significant, although there was some indication of a sex-by-genotype interaction for lifetime reproductive success at the suggestive QTL on chromosome 26. This implies that sexual antagonism may play a role in maintaining genetic variation at this QTL. Our findings provide candidate regions for a classic avian life-history trait that will be useful for future studies examining the molecular and cellular function of, as well as evolutionary mechanisms operating at, these loci.

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The purpose of this study was to conduct a habitat suitability analysis of the critically endangered Florida panther (Felis concolor coryi) in Florida. We gathered land cover, population and road data from the Florida Geographic Data Library and performed map algebra using ESRI’s ArcGIS to compile a suitable habitat map. We found that there is 20381.7 km² of highly suitable habitat and 557124.4 km² of less desirable but usable habitat for the Florida panther. The highest concentration of highly suitable habitat is in Big Cypress National Park, with smaller patches in Tates Hell State Forest and along the southeast portion of the Panhandle. Due to extensive fragmentation, however, and without establishment of habitat linkages to the existing southern population, there is little chance of survival of additional panther populations in much of northern Florida.

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Recently, two international standard organizations, ISO and OGC, have done the work of standardization for GIS. Current standardization work for providing interoperability among GIS DB focuses on the design of open interfaces. But, this work has not considered procedures and methods for designing river geospatial data. Eventually, river geospatial data has its own model. When we share the data by open interface among heterogeneous GIS DB, differences between models result in the loss of information. In this study a plan was suggested both to respond to these changes in the information envirnment and to provide a future Smart River-based river information service by understanding the current state of river geospatial data model, improving, redesigning the database. Therefore, primary and foreign key, which can distinguish attribute information and entity linkages, were redefined to increase the usability. Database construction of attribute information and entity relationship diagram have been newly redefined to redesign linkages among tables from the perspective of a river standard database. In addition, this study was undertaken to expand the current supplier-oriented operating system to a demand-oriented operating system by establishing an efficient management of river-related information and a utilization system, capable of adapting to the changes of a river management paradigm.

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New business and technology platforms are required to sustainably manage urban water resources [1,2]. However, any proposed solutions must be cognisant of security, privacy and other factors that may inhibit adoption and hence impact. The FP7 WISDOM project (funded by the European Commission - GA 619795) aims to achieve a step change in water and energy savings via the integration of innovative Information and Communication Technologies (ICT) frameworks to optimize water distribution networks and to enable change in consumer behavior through innovative demand management and adaptive pricing schemes [1,2,3]. The WISDOM concept centres on the integration of water distribution, sensor monitoring and communication systems coupled with semantic modelling (using ontologies, potentially connected to BIM, to serve as intelligent linkages throughout the entire framework) and control capabilities to provide for near real-time management of urban water resources. Fundamental to this framework are the needs and operational requirements of users and stakeholders at domestic, corporate and city levels and this requires the interoperability of a number of demand and operational models, fed with data from diverse sources such as sensor networks and crowsourced information. This has implications regarding the provenance and trustworthiness of such data and how it can be used in not only the understanding of system and user behaviours, but more importantly in the real-time control of such systems. Adaptive and intelligent analytics will be used to produce decision support systems that will drive the ability to increase the variability of both supply and consumption [3]. This in turn paves the way for adaptive pricing incentives and a greater understanding of the water-energy nexus. This integration is complex and uncertain yet being typical of a cyber-physical system, and its relevance transcends the water resource management domain. The WISDOM framework will be modeled and simulated with initial testing at an experimental facility in France (AQUASIM – a full-scale test-bed facility to study sustainable water management), then deployed and evaluated in in two pilots in Cardiff (UK) and La Spezia (Italy). These demonstrators will evaluate the integrated concept providing insight for wider adoption.

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O mapeamento da imunorreatividade ao neuropeptídio FMRF-amida no SNC e na musculatura pediosa de Megalobulimus oblongus foi realizado com o objetivo de dar continuidade aos estudos que vem sendo realizados nesta espécie, com o interesse em estabelecê-lo como modelo experimental em estudos neurobiológicos. O neuropeptídio FMRF-amida foi o primeiro peptídio nativo de invertebrados a ser purificado e seqüenciado, a partir do extrato de gânglios cardioativos do molusco Macrocallista nimbosa. Ele atuaria sobre os receptores metabotrópicos, induzindo a abertura dos canais iônicos de K+ tipo S (sensíveis à serotonina (5HT)), hiperpolarizando a membrana celular e assim, aumentando o limiar para o desencadeamento do potencial de ação. A distribuição da imunorreatividade à FMRF-amida em M. oblongus foi investigada empregando-se a técnica imunohistoquímica com anticorpo não-marcado de Sternberger (1979). Todos os gânglios nervosos centrais apresentaram neurônios e fibras FLI (FMRF-amide-like immunoreactivity), assim como suas comissuras, conetivos e a maioria dos nervos emergentes destes gânglios. Nos cortes da musculatura pediosa observou-se também uma intensa imunorreatividade a FMRF-amida. O maior número de neurônios FLI foi encontrado nos gânglios cerebrais com seus tamanhos variando de pequeno a grande. O corpo dorsal apresentou grande quantidade de fibras viii imunomarcadas. No mesocérebro foram detectados alguns agrupamentos FLI junto ao neuropilo e à comissura cerebral e neurônios dispersos na sua porção ântero-medial. O pró-cérebro mostrou-se repleto de neurônios globulosos FLI. Vários agrupamentos foram observados nos lobos pedal, pleural e comissural do pós-cérebro. Nos gânglios pedais houve intensa imunomarcação em agrupamentos neuronais localizados principalmente nas regiões posterior e lateral dos gânglios. Na região anterior foi observado um par de neurônios gigantes FLI. Uma distribuição homogênea de neurônios FLI foi observada por toda a extensão dos gânglios pleurais, com a exceção de apenas um neurônio grande localizado no gânglio pleural esquerdo. A diferença no tamanho dos dois gânglios parietais foi constatada também em M. oblongus. No hemigânglio esquerdo, o menor, foi identificado um neurônio gigante (300 µm). O gânglio direito apresentou um número maior de neurônios FLI, de tamanhos variados. O gânglio visceral foi a estrutura que mais apresentou neurônios grandes e gigantes por toda a sua extensão, com imunorreatividades variáveis. O par de gânglios bucais possuía agrupamentos neuronais FLI médios e grandes. Os neurônios gigantes não se mostraram imunorreativos, ou foram apenas levemente imunomarcados no trofospôngio. Na musculatura pediosa foram observadas fibras nervosas de diferentes calibres nas regiões dorsal, medial e ventral e sobre as células musculares. Identificaram-se gânglios nervosos nos pontos de intersecção dos ramos nervosos e malhas nervosas que formavam plexos nervosos nas regiões ventral e dorsal da musculatura pediosa de M. oblongus.

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O conhecimento referente à inervação da musculatura pediosa do caracol pulmonado Megalobulimus oblongus, é um subsídio importante na complementação de estudos morfológicos, neuroquímicos e comportamentais já realizados e, no fornecimento de informações básicas para trabalhos sobre os repertórios comportamentais básicos deste animal. O presente trabalho teve como objetivos descrever a distribuição anatômica dos nervos provenientes dos gânglios pedais de Megalobulimus oblongus, mapear os neurônios localizados nos gânglios nervosos centrais que enviam projeções para nervos do tronco posterior pedal deste animal, através de marcação retrógrada com cloreto de cobalto e verificar quais áreas periféricas são inervadas pelos ramos dos troncos nervosos posteriores, através de marcação anterógrada com cloreto de cobalto. A descrição dos nervos pedais foi baseada em dissecações dos nervos pedais de animais e secções histológicas da região de projeção dos nervos dos gânglios pedais. Foram descritos dez troncos nervosos, cinco dorsais e cinco ventrais, emergindo de cada gânglio pedal, que se ramificam em 41 nervos pedais, originados próximos ao gânglio. Destes, seis suprem a musculatura retratora do pé, um supre a glândula suprapediosa e 34 suprem a musculatura pediosa e integumento do pé. Neurônios marcados através dos nervos pedais NP7-NP10 foram encontrados em todos os gânglios do complexo ganglionar subesofageal, principalmente nos gânglios ipsilaterais à marcação. Foi possível verificar que as fibras marcadas que penetram através dos nervos ventralmente no gânglio pedal, mostram-se em grande quantidade no neuropilo, comissuras pedais (principalmente a comissura anterior) e conetivos. Algumas fibras que cruzam para o gânglio pedal contralateral seguem através do conetivo pedal-pleural para o gânglio pleural também contralateral à marcação. O maior número de neurônios foi marcado no gânglio pedal ipsilateral à marcação. Os gânglios cerebrais não apresentaram somas neuronais marcados, somente fibras terminando no mesocérebro, pós-cérebro, comissura e neuropilo entre o pró-cérebro e o mesocérebro. As fibras nervosas marcadas foram vistas percorrendo a região póstero-medial da musculatura pediosa e enviando ramificações direcionadas lateralmente e para a superfície dorsal e ventral da porção pediosa. Nestas regiões foram encontradas terminações nervosas diretamente em fibras musculares e entre as células epiteliais da região ventral do pé.