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À medida que oportunidades de emprego para toda a vida escasseiam, altas taxas de desemprego têm despertado o interesse por empreendedorismo. A salvação passa a ser a empregabilidade, sendo a educação empreendedora apontada como uma das áreas chave para fazer com que todos descubram potencialidades inovadoras e criativas despertando comportamentos empreendedores. A inserção dos jovens no mercado de trabalho é neste momento um dos maiores problemas da ilha de São Vicente com 23,3% de desempregados numa população maioritariamente jovem (65,7%) segundo INE (Instituto Nacional de Estatística). É neste contexto marcado por instabilidade e incerteza, que o Centro de Juventude de São Vicente tem vindo a promover a formação profissional oferecendo cursos de curta duração visando a inserção sócio económica de jovens carenciados e em situação de risco. Com base num suporte teórico que revela a possibilidade de desenvolver o espírito empreendedor através do ensino, optou-se pela metodologia de estudo de caso para analisar de que forma o Centro de Juventude de São Vicente contribui na formação para a empregabilidade e/ou no despertar do espírito empreendedor. Os resultados revelam que o Centro está dando os primeiros passos nesse sentido e que terá um papel importante no estímulo e incentivo ao trabalho por conta própria através da formação profissional, desde que em estreita articulação com o IEFP (Instituto do Emprego e Formação Profissional) e o mercado de trabalho. Visando uma mudança de mentalidade tem propiciado aos jovens um contexto de estímulo à iniciativa sobretudo através do apoio psicológico e na busca de financiamento. While opportunities for lifetime jobs are decreasing, high unemployment rates have aroused the interest in entrepreneurship. Employability will be the solution, being entrepreneurial education pointed out as one of the key factors in finding out innovative and creative potentialities as well as in stimulating entrepreneurial behaviours. Inserting young people in the labour market is, at present, one of the biggest problems in S.Vicente, an island with 23,3% of unemployed in a population mostly constituted by young people (65,7%), according to INE (National Institute of Statistics). In this context characterised by instability and uncertainty, the Youth Centre in S.Vicente has been promoting professional training through short courses aimed at socioeconomic insertion of young people in vulnerable and risky situations. Based on a theoretical support which points out the possibility of developing entrepreneurial spirit through education, the case study methodology was selected in order to analyse how the Youth Centre contributes through its training courses to employability and/or entrepreneurial spirit. The results obtained indicate that the Centre is taking its first steps in this direction and will play an important role in encouraging self-employment, through professional training. This has to be carried out in close relationship with both IEFP (Institute of Employment and Professional Training) and the labour market. With a view to changing mentalities, the Centre has been providing young people with a context capable of stimulating initiative, especially by supplying psychological support and helping them find financing sources.

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The problem of small Island Developing States (SIDS) is quite recent, end of the 80s and 90s, still looking for a theoretical consolidation. SIDS, as small states in development, formed by one or several islands geographically dispersed, present reduced population, market, territory, natural resources, including drinkable water, and, in great number of the cases, low level of economic activity, factors that together, hinder the gathering of scale economies. To these diseconomies they come to join the more elevated costs in transports and communications which, allies to lower productivities, to a smaller quality and diversification of its productions, which difficult its integration in the world economy. In some SIDS these factors are not dissociating of the few investments in infrastructures, in the formation of human resources and in productive investments, just as it happens in most of the developing countries. In ecological terms, many of them with shortage of natural resources, but integrating important ecosystems in national and world terms, but with great fragility relatively to the pollution action, of excessive fishing, of uncontrolled development of tourism, factors that, conjugated and associated to the stove effect, condition the climate and the slope of the medium level of the sea water and therefore could put in cause the own survival of some of them. The drive to the awareness of the international community towards its problems summed up with the accomplishment by the United Nations in the Barbados’s Conference, 1994 where the right to the development was emphasized, through the going up the appropriate strategies and the Programme of Action for the Sustainable Development of the SIDS. The orientation of the regional and international cooperation in that sense, sharing technology (namely clean technology and control and administration environmental technology), information and creation of capacity-building, supplying means, including financial resources, creating non discriminatory and just trade rules, it would drive to the establishment of a world system economically more equal, in which the production, the consumption, the pollution levels, the demographic politics were guided towards the sustainability. It constituted an important step for the recognition for the international community on the specificities of those states and it allowed the definition of a group of norms and politics to implement at the national, regional and international level and it was important that they continued in the sense of the sustainable development. But this Conference had in its origin previous summits: the Summit of Rio de Janeiro about Environment and Development, accomplished in 1992, which left an important document - the Agenda 21, in the Conference of Stockholm at 1972 and even in the Conference of Ramsar, 1971 about “Wetlands.” CENTRO DE ESTUDOS AFRICANOS Occasional Papers © CEA - Centro de Estudos Africanos 4 Later, the Valletta Declaration, Malta, 1998, the Forum of Small States, 2002, get the international community's attention for the problems of SIDS again, in the sense that they act to increase its resilience. If the definition of “vulnerability” was the inability of the countries to resist economical, ecological and socially to the external shocks and “resilience” as the potential for them to absorb and minimize the impact of those shocks, presenting a structure that allows them to be little affected by them, a part of the available studies, dated of the 90s, indicate that the SIDS are more vulnerable than the other developing countries. The vulnerability of SIDS results from the fact the they present an assemblage of characteristics that turns them less capable of resisting or they advance strategies that allow a larger resilience to the external shocks, either anthropogenic (economical, financial, environmental) or even natural, connected with the vicissitudes of the nature. If these vulnerability factors were grouped with the expansion of the economic capitalist system at world level, the economic and financial globalisation, the incessant search of growing profits on the part of the multinational enterprises, the technological accelerated evolution drives to a situation of disfavour of the more poor. The creation of the resilience to the external shocks, to the process of globalisation, demands from SIDS and of many other developing countries the endogen definition of strategies and solid but flexible programs of integrated development. These must be assumed by the instituted power, but also by the other stakeholders, including companies and organizations of the civil society and for the population in general. But that demands strong investment in the formation of human resources, in infrastructures, in investigation centres; it demands the creation capacity not only to produce, but also to produce differently and do international marketing. It demands institutional capacity. Cape Verde is on its way to this stage.

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Abstract OBJECTIVE To identify the factors associated with involuntary hospital admissions of technology-dependent children, in the municipality of Ribeirão Preto, São Paulo State, Brazil. METHOD A cross-sectional study, with a quantitative approach. After an active search, 124 children who qualified under the inclusion criteria, that is to say, children from birth to age 12, were identified. Data was collected in home visits to mothers or the people responsible for the children, through the application of a questionnaire. Analysis of the data followed the assumptions of the Generalized Linear Models technique. RESULTS 102 technology-dependent children aged between 6 months and 12 years participated in the study, of whom 57% were male. The average number of involuntary hospital admissions in the previous year among the children studied was 0.71 (±1.29). In the final model the following variables were significantly associated with the outcome: age (OR=0.991; CI95%=0.985-0.997), and the number of devices (OR=0.387; CI95%=0.219-0.684), which were characterized as factors of protection and quantity of medications (OR=1.532; CI95%=1.297-1.810), representing a risk factor for involuntary hospital admissions in technology-dependent children. CONCLUSION The results constitute input data for consideration of the process of care for technology-dependent children by supplying an explanatory model for involuntary hospital admissions for this client group.

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Biology of the leaf gall inducer Neotrioza tavaresi Crawford, 1925 (Hemiptera, Psyllidae) on strawberry guava tree (Psidium cattleianum). A field study was conducted in Curitiba region, State of Paraná, southern Brazil, to describe the life cycle of Neotrioza tavaresi Crawford, 1925, a leaf galling insect in strawberry guava trees (Psidium cattleianum). Three cycles were observed (1997, 1998, 1999) during regular field trips and the insects were observed in Piraquara municipality, where 15 samples with 50 infested leaves were sampled in the 1997-98 cycle. Galls were dissected for detailed studies. Neotrioza tavaresi has a univoltine cycle in which adult individuals were found inside the galls from August onwards. The sexually mature insects with sex ratio 1, emerged from the galls after their dehiscence caused by feeding of the adult insects on the gall walls. Adult emergence started in early October and ended by early December, with its peak in November. Copulation took place as soon as adults exit the gall and egg laying started the next day. Females had more than 100 ovarioles containing 218.7±44.7 (n=50) fully formed eggs. This indicated the short sexual adult life-span (aprox. 5-7 days) of the species, also characterized by a concentrated oviposition. Adult individuals fed and laid their eggs on younger shoots of the plant. The bottoms of the yellowish eggs were inserted into the leaf tissue, mainly on its adaxial edge (78.1%). The nymphs hatched and, as they fed on the adaxial side of expanding leaves, modified the cell growth pattern and the round-shape galls developed on the adaxial side with one insect inside. The gall wall showed distinct layers, with the inner one suppliyng the food to the insects, and the outer layer supplying gall protection. Nymphs went through five instars and the exuviae remained stuck on a ball of wax inside the gall. All parasitoids found were Hymenoptera belonging to Chalcidoidea: Eulophidae (1 sp), Pteromalidae (2 spp) and Encyrtidae (3 spp). The findings suggest that leaf gall inducer and parasitoids insects and plant life cycles are closely connected and both leaf sprouting and gall opening seem to be triggered by the same environmental and plant conditions. The high abundance of shoots may favor insect performance as adult individuals can easily find an ideal place for feeding, copulating and laying eggs.

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Apresentam‑se os principais resultados obtidos nas duas missões arqueológicas patrocinadas pelo Centro Português de Actividades Subaquáticas (CPAS) à ilha de São Vicente (República de Cabo Verde), em 1998 e em 2005. Em 1998, confirmou‑se o efectivo interesse arqueológico do sítio, localizado sobre o mar, em local abrigado da vasta baía de Salamansa, situada na parte setentrional da ilha, tendo‑se registado a respectiva extensão e estratigrafia e procedido à colheita de amostras para datação. Embora os resultados dessa campanha tivessem sido publicados, indicando estação de carácter habitacional, revelada pela notável acumulação de conchas, acompanhada de abundantes fragmentos de cerâmicas manuais, de produção africana, mantinha‑se indefinida a sua verdadeira natureza. Impunha‑se, assim, proceder à escavação integral da área que ainda subsistia da estação — sujeita de forma contínua a forte erosão marinha — bem como à colheita de novos materiais para datação, de forma a confirmar as conclusões preliminares anteriormente obtidas, objectivos que se concretizaram em 2005. Deste modo, foi possível concluir que, contrariando a hipótese, de início considerada, de poder corresponder a um testemunho da ocupação da ilha em época anterior à chegada dos Portugueses — hipótese que já as primeiras datas de radiocarbono contradiziam — se trata de um sítio onde uma unidade habitacional construída por muros de pedra seca, de planta ortogonal, revela inspiração europeia, aliás sublinhada pelos materiais exumados, onde estão representados produtos com tal origem, como cachimbos de caulino, vidros, faianças portuguesas, e projécteis de armas de fogo, a par de objectos oriundos do Extremo Oriente, num quadro dominado pelas produções cerâmicas africanas. Esta situação evidencia um estabelecimento cuja ocupação se centrou no século XVII, conforme indicam os materiais recolhidos e os resultados das datações obtidas, francamente aberto aos contactos de longa distância, apesar do isolamento do local escolhido. Os restos faunísticos recolhidos, com a presença deburro e de boi, sugerem um estacionamento sedentário, sendo a alimentação assegurada essencialmente pela captura de tartarugas, pela pesca e pela recolecção de moluscos marinhos (especialmente grandes lapas) e complementada pelo consumo de cabra, que poderia ser doméstica ou caçada, dado o estado selvagem a que retornou ali esta espécie. na última parte do trabalho, discutem‑se as diversas hipóteses susceptíveis de explicar esta estação — desde um entreposto comercial relacionado com a exploração agro‑pecuária da ilha de Santo Antão, passando por pequeno estabelecimento especializado de apoio à navegação, com a produção de carne salgada de tartaruga, até ter constituído refúgio relacionado com a intensa pirataria vigente à época no arquipélago, tendo presente os elementos históricos conhecidos, que, aliás, indicam que o início da ocupação permanente de São Vicente só se produziu a partir da segunda década do século XIX. Seja como for, a forte componente cultural africana revelada pelo espólio destes primeiros ocupantes da ilha expressa‑se também pelos rituais que terão envolvido o abandono do estabelecimento, com o enterramento de dois vasos emborcados sob o chão da habitação explorada, e a deposição de uma pequena taça, nas mesmas circunstâncias, junto à parede da mesma, do lado externo.

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Abstract Purpose: To test the hypothesis that simultaneous closure of at least 2 independent vascular territories supplying the spinal cord and/or prolonged hypotension may be associated with symptomatic spinal cord ischemia (SCI) after thoracic endovascular aortic repair (TEVAR). Methods: A pattern matching algorithm was used to develop a risk model for symptomatic SCI using a prospective 63-patient single-center cohort to test the positive predictive value (PPV) of prolonged intraoperative hypotension and/or simultaneous closure of at least 2 of 4 the vascular territories supplying the spinal cord (left subclavian, intercostal, lumbar, and hypogastric arteries). This risk model was then applied to data extracted from the multicenter European Registry on Endovascular Aortic Repair Complications (EuREC). Between 2002 and 2010, the 19 centers participating in EuREC reported 38 (1.7%) cases of symptomatic spinal cord ischemia among the 2235 patients in the database. Results: In the single-center cohort, direct correlations were seen between the occurrence of symptomatic SCI and both prolonged intraoperative hypotension (PPV 1.00, 95% CI 0.22 to 1.00, p = 0.04) and simultaneous closure of at least 2 independent spinal cord vascular territories (PPV 0.67, 95% CI 0.24 to 0.91, p = 0.005). Previous closure of a single vascular territory was not associated with an increased risk of symptomatic spinal cord ischemia (PPV 0.07, 95% CI 0.01 to 0.16, p = 0.56). The combination of prolonged hypotension and simultaneous closure of at least 2 territories exhibited the strongest association (PPV 0.75, 95% CI 0.38 to 0.75, p<0.0001). Applying the model to the entire EuREC cohort found an almost perfect agreement between the predicted and observed risk factors (kappa 0.77, 95% CI 0.65 to 0.90). Conclusion: Extensive coverage of intercostal arteries alone by a thoracic stent-graft is not associated with symptomatic SCI; however, simultaneous closure of at least 2 vascular territories supplying the spinal cord is highly relevant, especially in combination with prolonged intraoperative hypotension. As such, these results further emphasize the need to preserve the left subclavian artery during TEVAR.

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Revenue management (RM) is a complicated business process that can best be described ascontrol of sales (using prices, restrictions, or capacity), usually using software as a tool to aiddecisions. RM software can play a mere informative role, supplying analysts with formatted andsummarized data who use it to make control decisions (setting a price or allocating capacity fora price point), or, play a deeper role, automating the decisions process completely, at the otherextreme. The RM models and algorithms in the academic literature by and large concentrateon the latter, completely automated, level of functionality.A firm considering using a new RM model or RM system needs to evaluate its performance.Academic papers justify the performance of their models using simulations, where customerbooking requests are simulated according to some process and model, and the revenue perfor-mance of the algorithm compared to an alternate set of algorithms. Such simulations, whilean accepted part of the academic literature, and indeed providing research insight, often lackcredibility with management. Even methodologically, they are usually awed, as the simula-tions only test \within-model" performance, and say nothing as to the appropriateness of themodel in the first place. Even simulations that test against alternate models or competition arelimited by their inherent necessity on fixing some model as the universe for their testing. Theseproblems are exacerbated with RM models that attempt to model customer purchase behav-ior or competition, as the right models for competitive actions or customer purchases remainsomewhat of a mystery, or at least with no consensus on their validity.How then to validate a model? Putting it another way, we want to show that a particularmodel or algorithm is the cause of a certain improvement to the RM process compared to theexisting process. We take care to emphasize that we want to prove the said model as the causeof performance, and to compare against a (incumbent) process rather than against an alternatemodel.In this paper we describe a \live" testing experiment that we conducted at Iberia Airlineson a set of flights. A set of competing algorithms control a set of flights during adjacentweeks, and their behavior and results are observed over a relatively long period of time (9months). In parallel, a group of control flights were managed using the traditional mix of manualand algorithmic control (incumbent system). Such \sandbox" testing, while common at manylarge internet search and e-commerce companies is relatively rare in the revenue managementarea. Sandbox testing has an undisputable model of customer behavior but the experimentaldesign and analysis of results is less clear. In this paper we describe the philosophy behind theexperiment, the organizational challenges, the design and setup of the experiment, and outlinethe analysis of the results. This paper is a complement to a (more technical) related paper thatdescribes the econometrics and statistical analysis of the results.

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Epigean ant communities in Atlantic Forest remnants of São Paulo: a comparative study using the guild concept. The guilds constitute a valuable ecological tool, because they allow conducting comparisons among environments under different conditions. The ants can be used as ecological indicators, mainly for the monitoring of degraded forest areas. The aim of this research was to study guild organization among the epigeous Formicidae living in Atlantic forest remnants of the State of São Paulo, Brazil. Ant collections were performed in three distinct Atlantic forest biome areas: arboreal littoral vegetation ("restinga") (Cananéia), semideciduous seasonal forest (Piracicaba) and dense ombrophylousforest (Pariquera-Açu). After identification, the ants were grouped into guilds, based on the ecological attributes of behavior and habit, according to the literature. Nine guilds were found; the semideciduous seasonal forest ecosystem presented eight of them, followed by the arboreal sandbank (7) and dense ombrophylous forest (6). The guilds found were: litter omnivorous and scavengers, granivorous species, specialist predators living in litter and soil, litter generalist predators, subterranean mealybug-dependent species, army ants, dominant or subdominants arboreal, that occasionally forage on the ground, soil or litter dominant and fungus-growers, using feces and insect body fragments. The guilds found can be used in the monitoring of the mirmecofauna in the Atlantic Forest biome, supplying insights for further ecological studies.

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OBJECTIVE: The objective of our study was to establish a standardized procedure for postmortem whole-body CT-based angiography with lipophilic and hydrophilic contrast media solutions and to compare the results of these two methods. MATERIALS AND METHODS: Minimally invasive postmortem CT angiography was performed on 10 human cadavers via access to the femoral blood vessels. Separate perfusion of the arterial and venous systems was established with a modified heart-lung machine using a mixture of an oily contrast medium and paraffin (five cases) and a mixture of a water-soluble contrast medium with polyethylene glycol (PEG) 200 in the other five cases. Imaging was executed with an MDCT scanner. RESULTS: The minimally invasive femoral approach to the vascular system provided a good depiction of lesions of the complete vascular system down to the level of the small supplying vessels. Because of the enhancement of well-vascularized tissues, angiography with the PEG-mixed contrast medium allowed the detection of tissue lesions and the depiction of vascular abnormalities such as pulmonary embolisms or ruptures of the vessel wall. CONCLUSION: The angiographic method with a water-soluble contrast medium and PEG as a contrast-agent dissolver showed a clearly superior quality due to the lack of extravasation through the gastrointestinal vascular bed and the enhancement of soft tissues (cerebral cortex, myocardium, and parenchymal abdominal organs). The diagnostic possibilities of these findings in cases of antemortem ischemia of these tissues are not yet fully understood.

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Tannery residues and coal mine waste are heavily polluting sources in Brazil, mainly in the Southern States of Rio Grande do Sul and Santa Catarina. In order to study the effects of residues of chrome leather tanning (sludge and leather shavings) and coal waste on soybean and maize crops, a field experiment is in progress since 1996, at the Federal University of Rio Grande do Sul Experimental Station, county of Eldorado do Sul, Brazil. The residues were applied twice (growing seasons 1996/97 and 1999/00). The amounts of tannery residues were applied according to their neutralizing value, at rates of up to 86.8 t ha-1, supplying from 671 to 1.342 kg ha-1 Cr(III); coal waste was applied at a total rate of 164 t ha-1. Crop yield and dry matter production were evaluated, as well as the nutrients (N, P, K, Ca, Mg, Cu and Zn) and Cr contents. Crop yields with tannery sludge application were similar to those obtained with N and lime supplied with mineral amendments. Plant Cr absorption did not increase significantly with the residue application. Tannery sludge can be used also to neutralize the high acidity developed in the soil by coal mine waste.

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The protective effect of cations, especially Ca and Mg, against aluminum (Al) rhizotoxicity has been extensively investigated in the last decades. The mechanisms by which the process occurs are however only beginning to be elucidated. Six experiments were carried out here to characterize the protective effect of Mg application in relation to timing, location and crop specificity: Experiment 1 - Protective effect of Mg compared to Ca; Experiment 2 - Protective effect of Mg on distinct root classes of 15 soybean genotypes; Experiment 3 - Effect of timing of Mg supply on the response of soybean cvs. to Al; Experiment 4 - Investigating whether the Mg protective effect is apoplastic or simplastic using a split-root system; Experiment 5 - Protective effect of Mg supplied in solution or foliar spraying, and Experiment 6 - Protective effect of Mg on Al rhizotoxicity in other crops. It was found that the addition of 50 mmol L-1 Mg to solutions containing toxic Al increased Al tolerance in 15 soybean cultivars. This caused soybean cultivars known as Al-sensitive to behave as if they were tolerant. The protective action of Mg seems to require constant Mg supply in the external medium. Supplying Mg up to 6 h after root exposition to Al was sufficient to maintain normal soybean root growth, but root growth was not recovered by Mg addition 12 h after Al treatments. Mg application to half of the root system not exposed to Al was not sufficient to prevent Al toxicity on the other half exposed to Al without Mg in rooting medium, indicating the existence of an external protection mechanism of Mg. Foliar spraying with Mg also failed to decrease Al toxicity, indicating a possible apoplastic role of Mg. The protective effect of Mg appeared to be soybean-specific since Mg supply did not substantially improve root elongation in sorghum, wheat, corn, cotton, rice, or snap bean when grown in the presence of toxic Al concentrations.

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The GO annotation dataset provided by the UniProt Consortium (GOA: http://www.ebi.ac.uk/GOA) is a comprehensive set of evidenced-based associations between terms from the Gene Ontology resource and UniProtKB proteins. Currently supplying over 100 million annotations to 11 million proteins in more than 360,000 taxa, this resource has increased 2-fold over the last 2 years and has benefited from a wealth of checks to improve annotation correctness and consistency as well as now supplying a greater information content enabled by GO Consortium annotation format developments. Detailed, manual GO annotations obtained from the curation of peer-reviewed papers are directly contributed by all UniProt curators and supplemented with manual and electronic annotations from 36 model organism and domain-focused scientific resources. The inclusion of high-quality, automatic annotation predictions ensures the UniProt GO annotation dataset supplies functional information to a wide range of proteins, including those from poorly characterized, non-model organism species. UniProt GO annotations are freely available in a range of formats accessible by both file downloads and web-based views. In addition, the introduction of a new, normalized file format in 2010 has made for easier handling of the complete UniProt-GOA data set.

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PURPOSE: Continuous positive airway pressure (CPAP) is the gold standard treatment for obstructive sleep apnea. However, the physiologic impact of CPAP on cerebral blood flow (CBF) is not well established. Ultrasound can be used to estimate CBF, but there is no widespread accepted protocol. We studied the physiologic influence of CPAP on CBF using a method integrating arterial diameter and flow velocity (FV) measurements obtained for each vessel supplying blood to the brain. METHODS: FV and lumen diameter of the left and right internal carotid, vertebral, and middle cerebral arteries were measured using duplex Doppler ultrasound with and without CPAP at 15 cm H(2)O, applied in a random order. Transcutaneous carbon dioxide (PtcCO(2)), heart rate (HR), blood pressure (BP), and oxygen saturation were monitored. Results were compared with a theoretical prediction of CBF change based on the effect of partial pressure of carbon dioxide on CBF. RESULTS: Data were obtained from 23 healthy volunteers (mean ± SD; 12 male, age 25.1 ± 2.6 years, body mass index 21.8 ± 2.0 kg/m(2)). The mean experimental and theoretical CBF decrease under CPAP was 12.5 % (p < 0.001) and 11.9 % (p < 0.001), respectively. The difference between experimental and theoretical CBF reduction was not statistically significant (3.84 ± 79 ml/min, p = 0.40). There was a significant reduction in PtcCO(2) with CPAP (p = <0.001) and a significant increase in mean BP (p = 0.0017). No significant change was observed in SaO(2) (p = 0.21) and HR (p = 0.62). CONCLUSION: Duplex Doppler ultrasound measurements of arterial diameter and FV allow for a noninvasive bedside estimation of CBF. CPAP at 15 cm H(2)O significantly decreased CBF in healthy awake volunteers. This effect appeared to be mediated predominately through the hypocapnic vasoconstriction coinciding with PCO(2) level reduction. The results suggest that CPAP should be used cautiously in patients with unstable cerebral hemodynamics.

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RÉSUMÉ L'Organisation Mondiale de la Santé (OMS) recommande d'administrer l'oxygène par concentrateurs dans les pays en voie de développement (PVD), les cylindres posant des problèmes logistiques et financiers trop importants. Cette technologie a été proposée aux enfants d'un hôpital sénégalais (Ndioum) qui présentaient les critères d'oxygénation de l'OMS. Les bénéfices cliniques et financiers ont été majeurs. En revanche, les connaissances des soignants sur les diverses techniques d'administration d'oxygène ainsi que les prestations du service de maintenance étaient insuffisantes. L'implantation de concentrateurs doit être encouragée dans les PVD, mais doit respecter une stratégie englobant enseignement, maintenance et suivi de l'opération. Diverses actions correctrices ont été entreprises à Ndioum où plusieurs concentrateurs fonctionnent désormais régulièrement. Summary: The World Health Organisation (WHO) recommends supplying oxygen in developing countries by concentra¬tors because cylinders pose considerable logistic and financial problems. This technology was employed to treat children in a hospital in Ndioum, Senegal, who met the WHO oxygenation criteria. There were clear clinical and financial benefits, but neither the nurses' knowledge of the various techniques of oxygen supply nor the maintenance service were satisfactory. The use of concentra¬tors should be encouraged in developing countries. A strategy including technical training, maintenance and monitoring should be adopted. Corrective actions were undertaken in Ndioum, and several concentrators are now being used on a regular basis.

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Peripheral nerve regeneration following injury occurs spontaneously, but many of the processes require metabolic energy. The mechanism of energy supply to axons has not previously been determined. In the central nervous system, monocarboxylate transporter 1 (MCT1), expressed in oligodendroglia, is critical for supplying lactate or other energy metabolites to axons. In the current study, MCT1 is shown to localize within the peripheral nervous system to perineurial cells, dorsal root ganglion neurons, and Schwann cells by MCT1 immunofluorescence in wild-type mice and tdTomato fluorescence in MCT1 BAC reporter mice. To investigate whether MCT1 is necessary for peripheral nerve regeneration, sciatic nerves of MCT1 heterozygous null mice are crushed and peripheral nerve regeneration was quantified electrophysiologically and anatomically. Compound muscle action potential (CMAP) recovery is delayed from a median of 21days in wild-type mice to greater than 38days in MCT1 heterozygote null mice. In fact, half of the MCT1 heterozygote null mice have no recovery of CMAP at 42days, while all of the wild-type mice recovered. In addition, muscle fibers remain 40% more atrophic and neuromuscular junctions 40% more denervated at 42days post-crush in the MCT1 heterozygote null mice than wild-type mice. The delay in nerve regeneration is not only in motor axons, as the number of regenerated axons in the sural sensory nerve of MCT1 heterozygote null mice at 4weeks and tibial mixed sensory and motor nerve at 3weeks is also significantly reduced compared to wild-type mice. This delay in regeneration may be partly due to failed Schwann cell function, as there is reduced early phagocytosis of myelin debris and remyelination of axon segments. These data for the first time demonstrate that MCT1 is critical for regeneration of both sensory and motor axons in mice following sciatic nerve crush.