The effects of arterial flow on platelet activation, thrombus growth, and stabilization.

Injury of an arterial vessel wall acutely triggers a multifaceted process of thrombus formation, which is dictated by the high-shear flow conditions in the artery. In this overview, we describe how the classical concept of arterial thrombus formation and vascular occlusion, driven by platelet activation and fibrin formation, can be extended and fine-tuned. This has become possible because of recent insight into the mechanisms of: (i) platelet-vessel wall and platelet-platelet communication, (ii) autocrine platelet activation, and (iii) platelet-coagulation interactions, in relation to blood flow dynamics. We list over 40 studies with genetically modified mice showing a role of platelet and plasma proteins in the control of thrombus stability after vascular injury. These include multiple platelet adhesive receptors and other junctional molecules, components of the ADP receptor signalling cascade to integrin activation, proteins controlling platelet shape, and autocrine activation processes, as well as multiple plasma proteins binding to platelets and proteins of the intrinsic coagulation cascade. Regulatory roles herein of the endothelium and other blood cells are recapitulated as well. Patient studies support the contribution of platelet- and coagulation activation in the regulation of thrombus stability. Analysis of the factors determining flow-dependent thrombus stabilization and embolus formation in mice will help to understand the regulation of this process in human arterial disease.

Intégration de méthodes de data mining dans le renseignement criminel : analyse par des structures issues de la théorie des graphes dans le profilage des stupéfiants

Data mining can be defined as the extraction of previously unknown and potentially useful information from large datasets. The main principle is to devise computer programs that run through databases and automatically seek deterministic patterns. It is applied in different fields of application, e.g., remote sensing, biometry, speech recognition, but has seldom been applied to forensic case data. The intrinsic difficulty related to the use of such data lies in its heterogeneity, which comes from the many different sources of information. The aim of this study is to highlight potential uses of pattern recognition that would provide relevant results from a criminal intelligence point of view. The role of data mining within a global crime analysis methodology is to detect all types of structures in a dataset. Once filtered and interpreted, those structures can point to previously unseen criminal activities. The interpretation of patterns for intelligence purposes is the final stage of the process. It allows the researcher to validate the whole methodology and to refine each step if necessary. An application to cutting agents found in illicit drug seizures was performed. A combinatorial approach was done, using the presence and the absence of products. Methods coming from the graph theory field were used to extract patterns in data constituted by links between products and place and date of seizure. A data mining process completed using graphing techniques is called ``graph mining''. Patterns were detected that had to be interpreted and compared with preliminary knowledge to establish their relevancy. The illicit drug profiling process is actually an intelligence process that uses preliminary illicit drug classes to classify new samples. Methods proposed in this study could be used \textit{a priori} to compare structures from preliminary and post-detection patterns. This new knowledge of a repeated structure may provide valuable complementary information to profiling and become a source of intelligence.

Lineage potential, plasticity and environmental reprogramming of epithelial stem/progenitor cells.

Recent evidence supports and reinforces the concept that environmental cues may reprogramme somatic cells and change their natural fate. In the present review, we concentrate on environmental reprogramming and fate potency of different epithelial cells. These include stratified epithelia, such as the epidermis, hair follicle, cornea and oesophagus, as well as the thymic epithelium, which stands alone among simple and stratified epithelia, and has been shown recently to contain stem cells. In addition, we briefly discuss the pancreas as an example of plasticity of intrinsic progenitors and even differentiated cells. Of relevance, examples of plasticity and fate change characterize pathologies such as oesophageal metaplasia, whose possible cell origin is still debated, but has important implications as a pre-neoplastic event. Although much work remains to be done in order to unravel the full potential and plasticity of epithelial cells, exploitation of this phenomenon has already entered the clinical arena, and might provide new avenues for future cell therapy of these tissues.

Tabela de vida de fertilidade de Lysiphlebus testaceipes (Cresson, 1880) (Hymenoptera, Aphidiidae) em Schizaphis graminum (Rondani, 1852) (Hemipera, Aphididae)

Life table analyses have been developed to understanding the impact of various sources of intrinsic and extrinsic mortalities on the rate of population growth. The understanding of the population increase of the parasitoids related to their hosts is important in biological control programs. This work had as objective to evaluate the survival and fertility of the parasitoid Lysiphlebus testaceipes (Cresson, 1880) on Schizaphis graminum (Rondani, 1852) as a host under fertility life table. The experiment were carried out in a climatic chamber at 25 ± 1ºC, RH 60 ± 10% and 10h photophase. To determine the immature mortality, the development time and the sex ratio of the parasitoid, 12 females of the parasitoid (less than one day old) and 240 nymphs of S. graminum (3 days old) were used. To evaluate the longevity and fertility of L. testaceipes, 15 females (less than one day old) were used. Nymphs of S. graminum (3 days old) were offered for each parasitoid female daily, until the female died, being in the 1st day - 300 nymphs; 2nd day - 250 nymphs; 3rd day - 200 nymphs; 4th day - 150 and in the other days a number of 50 nymphs. L. testaceipes had an immature mortality of 22,2%, and a development time of males and females of 9.0 and 9.1 days, respectively. The females of L. testaceipes laid, in it first life day, 257.8 eggs, and they survived up until seven days. The net reproduction rate (Ro) and the intrinsic rate of increase (r m) were respectively, 301.9 and 0.513. The finite rate of increase (l) was 1.67 females per day, the mean length of a generation (T) was 11.13 days and the time to duplicate the population (TD) was 1.35 weeks. The parasitoid L. testaceipes have a high potential of population growth on S. graminum as a host under the analyzed conditions.

Why ethnic fractionalization? Polarization, ethnic conflict and growth

This paper ia an attempt to clarify the relationship between fractionalization,polarization and conflict. The literature on the measurement of ethnic diversityhas taken as given that the proper measure for heterogeneity can be calculatedby using the fractionalization index. This index is widely used in industrialeconomics and, for empirical purposes, the ethnolinguistic fragmentation isready available for regression exercises. Nevertheless the adequacy of asynthetic index of hetergeneity depends on the intrinsic characteristicsof the heterogeneous dimension to be measured. In the case of ethnicdiversity there is a very strong conflictive dimension. For this reasonwe argue that the measure of heterogeneity should be one of the class ofpolarization measures. In fact the intuition of the relationship betweenconflict and fractionalization do not hold for more than two groups. Incontrast with the usual problem of polarization indices, which are ofdifficult empirical implementation without making some arbitrary choiceof parameters, we show that the RQ index, proposed by Reynal-Querol (2002),is the only discrete polarization measure that satisfies the basic propertiesof polarization. Additionally we present a derivation of the RQ index froma simple rent seeking model. In the empirical section we show that whileethnic polarization has a positive effect on civil wars and, indirectly ongrowth, this effect is not present when we use ethnic fractionalization.

Leasing como alternativa de financiamento de empresas em Cabo Verde - Análise prática de efeitos económicos, financeiros e contabilísticos

Criar mecanismos que produzam e dinamizem o alcance de novos produtos financeiros surge como uma condição necessária para estimular o investimento. Além das condições intrínsecas próprias de uma economia o financiamento é quase que a espinha dorsal para favorecer o desenvolvimento e crescimento económicos. Diversificar as fontes de financiamento para que estas se adaptem à realidade económico-financeira das empresas é essencial, pois não só possibilita o crescimento das empresas nacionais, mas também cria um ambiente de negócios propício ao investimento externo. Convicto da relevância, o presente trabalho tem como escopo uma temática que a nível nacional pouco se tem abordado: trata-se locação financeira que na gíria financeira é entendida por leasing - que de forma sintética se traduz num contrato pelo qual uma das partes concede à outra o gozo temporário de uma coisa contra uma retribuição, e que posteriormente pode ser adquirida, num prazo convencionado, mediante pagamento de um preço determinado ou determinável, nos termos do próprio contrato. O enfoque está em estudar a relevância assumida pelo leasing enquanto fonte de financiamento de médio e longo prazo, no contexto cabo-verdiano, comparativamente à outra fonte – empréstimo bancário de médio e longo prazo. O trabalho reveste-se de uma componente teórica e uma prática. Na componente teórica trata-se do tema no geral, abrangendo uma resenha histórica, o enquadramento legal, das sociedades de locação financeira e dos contratos de locação financeira, tratamento contabilístico, as características específicas que se associam ao tema em apreço e igualmente uma breve análise fiscal. A parte prática desenvolve uma análise comparativa do leasing com o empréstimo bancário de médio e longo prazo onde foram retiradas as conclusões chegadas com o estudo. Resumidamente, pode-se que o leasing é certamente uma das melhores opções de financiamento não só para empresas como igualmente para clientes particulares, sendo, uma opção rápida, simples e vantajosa para o cliente bancário, especialmente se o facto de a propriedade do bem não pertencer ao titular do leasing não causar qualquer incómodo. Create mechanisms that produce and streamline the range of new financial products emerges as a necessary condition to stimulate investment. In addition to its own intrinsic conditions of an economy funding is almost the backbone to promote economic development and growth. Diversify the sources of funding for these adapt to the reality of the economic-financial firms is essential because not only enables the growth of domestic companies, but also creates a business environment conducive to foreign investment. Convinced of the relevance, this work is scoped to a theme that nationally there has been little discussed: it is leasing in slang that is understood by financial leasing - which synthetically translates into a contract whereby one party grants to the another the temporary enjoyment of a thing against retribution, and that can later be acquired within the agreed upon payment of a specified or ascertainable under the contract. The focus is on studying the relevance assumed by leasing as a source of financing medium and long term, the Cape Verdean context, compared to other sources - bank loan of medium and long term. The work has a theoretical and a practical component. In the theoretical part it is the theme in general, covering a historical perspective, the legal framework, the leasing companies and financial leasing contracts, accounting treatment, specific characteristics that are associated to the topic at hand and equally a brief fiscal analysis. The practical part develops a comparative analysis of leasing with bank loan of medium and long term which were withdrawn with the conclusions reached with the study. Briefly, it may be that leasing is certainly one of the best financing options not only by companies as also by private customers, being a fast, simple and profitable for the bank customer, especially if the fact that the ownership of the property does not belong the holder of the lease does not cause any discomfort.

Circulation of private notes during a currency shortage

This paper provides a search theoretical model that captures two phenomena that have characterized several episodes of monetary history: currency shortages and the circulation of privately issued notes. As usual in these models, the media of exchange are determined as part of the equilibrium. We characterize all the different equilibria and specify the conditions under which there is a currency shortage and/or privately issued notes are used as means of payment. There is multiplicity of equilibria for the entire parameter space, but there always exist an equilibrium in which notes circulate, either alone or together with coins. Hence, credit is a self-fulfilling phenomenon that depends on the beliefs of agents about the acceptability and future repayment of notes. The degree of circulation of coins depends on two crucial parameters, the intrinsic utility of holding coins and the extent with which it is possible to find exchange opportunities in the market.

Money, fame and the allocation of talent: Brain drain and the institution of science

The earning structure in science is known to be flat relative to the one in theprivate sector, which could cause a brain drain toward the private sector. In thispaper, we assume that agents value both money and fame and study the role ofthe institution of science in the allocation of talent between the science sector andthe private sector. Following works on the Sociology of Science, we model theinstitution of science as a mechanism distributing fame (i.e. peer recognition). Weshow that since the intrinsic performance is less noisy signal of talent in the sciencesector than in the private sector, a good institution of science can mitigate thebrain drain. We also find that providing extra monetary incentives through themarket might undermine the incentives provided by the institution and therebyworsen the brain drain. Finally, we study the optimal balance between monetaryand non-monetary incentives in science.

Long-run selection and the work ethic

That individuals contribute in social dilemma interactions even when contributing is costly is a well-established observation in the experimental literature. Since a contributor is always strictly worse off than a non-contributor the question is raised if an intrinsic motivation to contribute can survive in an evolutionary setting. Using recent results on deterministic approximation of stochastic evolutionary dynamics we give conditions for equilibria with a positive number of contributors to be selected in the long run.

Concepção de uma Estratégia de Geoconservação para Cabo Verde e sua Aplicação à Ilha de Santiago

A singularidade de certos registos geológicos impressos em rochas, as peculiaridades estruturais e dinâmicas dos diversos elementos dos geossistemas, a análise dos seus valores intrínsecos, bem como da sua vulnerabilidade e dos perigos de degradação que os podem afectar, entre outros parâmetros, são factores que concorrem para a necessidade de assegurar a conservação do património geológico. É neste contexto que surge a geoconservação que preconiza a gestão do património geológico com base num conjunto de medidas e acções para a identificação, manutenção ou recuperação do valor natural dos elementos da geodiversidade numa perspectiva de sustentabilidade dos recursos geológicos que integram a componente abiótica do sistema natural. A geoconservação, à escala internacional, tem um desenvolvimento irregular. Enquanto algumas regiões estão bastante avançadas, como na Europa, outras revelam ainda alguma inércia relativamente à implementação de iniciativas que se devem enquadrar no âmbito da conservação da Natureza e do ordenamento do território. Em África, são ainda pontuais os exemplos de geoconservação pelo que, este trabalho, pretende ser promotor de uma política de geoconservação neste continente. No presente trabalho, concebemos uma estratégia de geoconservação para Cabo Verde e aplicamo-la, a título de exemplo, à ilha de Santiago. A metodologia utilizada, baseada em critérios internacionalmente reconhecidos e aceites para o inventário do património geológico de valor científico, consiste no estabelecimento de “categorias temáticas” que representam as características e evolução geológica do arquipélago. Foram propostas nove categorias para Cabo Verde e, para cada uma delas, foram inventariados diversos locais de interesse, dos quais 40 foram propostos como geossítios na ilha de Santiago. Com base nestes geossítios, propuseram-se linhas metodológicas para as etapas subsequentes que integram uma estratégia de geoconservação, nomeadamente, a quantificação, classificação, conservação, valorização, divulgação e monitorização de geossítios. Embora a conservação da geodiversidade esteja prevista, embora de forma pouco clara, na actual legislação ambiental cabo-verdiana, a execução desta estratégia de geoconservação poderá representar um dos primeiros passos para a definição, caracterização e valorização, sistemáticas, do património geológico nacional e contribuir para a implementação de uma política de sustentabilidade ambiental para o país.

Patterns of calcium-binding proteins support parallel and hierarchical organization of human auditory areas.

The human primary auditory cortex (AI) is surrounded by several other auditory areas, which can be identified by cyto-, myelo- and chemoarchitectonic criteria. We report here on the pattern of calcium-binding protein immunoreactivity within these areas. The supratemporal regions of four normal human brains (eight hemispheres) were processed histologically, and serial sections were stained for parvalbumin, calretinin or calbindin. Each calcium-binding protein yielded a specific pattern of labelling, which differed between auditory areas. In AI, defined as area TC [see C. von Economo and L. Horn (1930) Z. Ges. Neurol. Psychiatr.,130, 678-757], parvalbumin labelling was dark in layer IV; several parvalbumin-positive multipolar neurons were distributed in layers III and IV. Calbindin yielded dark labelling in layers I-III and V; it revealed numerous multipolar and pyramidal neurons in layers II and III. Calretinin labelling was lighter than that of parvalbumin or calbindin in AI; calretinin-positive bipolar and bitufted neurons were present in supragranular layers. In non-primary auditory areas, the intensity of labelling tended to become progressively lighter while moving away from AI, with qualitative differences between the cytoarchitectonically defined areas. In analogy to non-human primates, our results suggest differences in intrinsic organization between auditory areas that are compatible with parallel and hierarchical processing of auditory information.

Drug innovation, prices and health

This article tries to reconcile economic-industrial policy with health policy when dealing with biomedical innovation and welfare state sustainability. Better health accounts for an increasingly large proportion of welfare improvements. Explanation is given to the welfare losses coming from the fact than industrial and health policy tend to ignore each other. Drug s prices reflecting their relative relative effectiveness send the right signal to the industry rewarding innovation with impact on quantity and quality of life- and to the buyers of health care services.The level of drug s public reimbursement indicates the social willingness to pay of the different national health systems, not only by means of inclusion, or rejection, in the basket of services covered, but especially establishing the proportion of the price that is going to be financed publicly.Reference pricing for therapeutic equivalents as the upper limit of the social willingness to pay- and two-tiered co-payments for users (avoidable and inversely related with the incremental effectiveness of de drug) are deemed appropriate for those countries concerned at the same time with increasing their productivity and maintaining its welfare state. Profits drive R&D but not its location. There is no intrinsic contradiction between high productivity and a consolidated National Health Service (welfare state) as the European Nordic Countries are telling us every day.

Biological cycle of Tenuipalpus heveae Baker (Acari, Tenuipalpidae) on leaflets of three rubber tree clones

Life cycle of Tenuipalpus heveae Baker (Acari, Tenuipalpidae) on leaflets from three rubber tree clones. The biological cycle of Tenuipalpus heveae Baker, 1945 (Tenuipalpidae), a potential rubber tree pest mite, was studied by the observation of individuals reared on leaflets of the clones GT 1, PB 235 and RRIM 600, in controlled environmental conditions. Three daily observations were done of 60 eggs on leaflets from each clone in order to verify the development of immature stages and the female oviposition. The fertility life table was constructed based in the collected data. Mites reared on PB 235 had faster rate of development, requiring less time in days, to double its population in number (TD), and had the highest values for egg production, female longevity, net reproductive rate (Ro), intrinsic rate of natural increase (r m) and finite rate of increase (λ). Lower reproductive values and the longest time necessary to reach adult stage were recorded for the mites on GT 1. In all studied clones, the deutonymphal phase had the highest viability, while the larval phase had the lowest, highlighted by the survivorship curve that indicated high mortality during this life stage. The clone PB 235 allowed the most suitable conditions for the development of T. heveae, followed by RRIM 600, while GT 1 was the less suitable substratum to rear this mite species.

A influência do e-learning no capital humano

Na Europa e nas últimas décadas do Século XX, a emergência da Sociedade de Informação veio impor às organizações a necessidade de que, para além das inovações tecnológicas, haja uma preocupação relativamente aos bens intangíveis como a informação, as novas metodologias de trabalho e o know how (Batista, 2002). Paralelamente a estas inovações, as Instituições de Ensino Superior têm contribuído para a evolução do Capital Humano, como ativo intangível intrínseco ao Homem. Em Portugal e no contexto do Ensino/Formação a Distância parecem continuar a existir, ainda, em algumas instituições, problemas de identificação, e de descriminação das vantagens no que concerne à estrutura aberta e flexível, com o estudante/formando a ter algumas dificuldades em adaptar o seu perfil e interesses profissionais ao tipo de aprendizagem que mais se lhe adequa. O e-learning surge como um método de Ensino/Formação a Distância, só possível com a especificidade dos processos pedagógicos e em complementaridade com as Tecnologias de Informação e Comunicação (TIC), uma vez que são estas que lhe dão o suporte necessário à sua concretização. O e-learning ao proporcionar novas formas de comunicação, de interação e de confronto de ideias, permite uma aprendizagem baseada na partilha de saberes, tendo em consideração as experiências e os objetivos profissionais dos formandos. Dentro destes pressupostos, achámos importante fazer uma investigação a partir de Instituições de Ensino Superior Portuguesas, de modo a percebermos qual o papel e a influência que o e-learning desempenha nos objetivos das organizações académicas em geral e no Capital Humano dos seus Estudantes/Formandos em particular. A partir da questão da investigação foram definidos os objetivos e hipóteses de investigação de modo a que ao ser enunciada uma metodologia esta englobe fatores que foquem os elementos necessários à confirmação, ou não, dos pressupostos enunciados. Foi analisada documentação diversa, criado um questionário e conduzidas entrevistas, de modo a obter e potenciar a informação necessária e suficiente para o efeito. A recolha de dados para posterior análise e os resultados depois de interpretados, permitirão responder aos propósitos expressos desde o início da investigação.

Reproduction and fertility life table of three aphid species (Macrosiphini) at different temperatures

Temperature is a key abiotic factor influencing the development and reproduction of aphids. The effect of temperature on the reproduction of three aphid species Aulacorthum solani (Kaltenbach), Macrosiphum euphorbiae (Thomas) and Uroleucon ambrosiae (Thomas) (Aphididae, Macrosiphini) has been investigated and fertility life tables were determined. Nymphs were reared in climatic chambers at temperatures of 16, 19, 22, 25, and 28 ± 1ºC, RH 70 ± 10% and 12 h photophase. Female adult aphids developed at these temperatures were then used in experiments in which pre-reproductive and reproductive periods were evaluated every 24 h. In addition, the number of nymphs produced and longevity were determined at each temperature. The reproduction period of A. solani and M. euphorbiae decreased with increasing temperature, whereas that of U. ambrosiae was maintained between 19 and 25ºC. The total number of nymphs produced by the aphids decreased as the temperature increased. The longevities of A. solani and M. euphorbiae decreased with increasing temperature but remained stable for U. ambrosiae between 19 and 25ºC. The largest survival rate (l x) and specific fertility (m x) values were found at 16 and 22ºC for all three species. The most favourable temperature for reproduction of A. solani, M. euphorbiae and U. ambrosiae was 22ºC, as demonstrated by the l x and m x profiles, the high values of net reproductive rates and intrinsic rates of increase, and the short intervals between generation and doubling times.