OPEN SOURCE SOFTWARE PROJECTS\u27 ATTRACTIVENESS, ACTIVENESS, AND EFFICIENCY AS A PATH TO SOFTWARE QUALITY: AN EMPIRICAL EVALUATION OF THEIR RELATIONSHIPS AND CAUSES

An organizational strategy to develop software has appeared in the market. Organizations release software source code open and hope to attract volunteers to improve their software, forming what we call an open source project. Examples of organizations that have used this strategy include IBM (Eclipse), SAP (Netweaver) and Mozilla (Thunderbird). Moreover, thousands of these projects have been created as a consequence of the growing amount of software source code released by individuals. This expressive phenomenon deserves attention for its sudden appearance, newness and usefulness to public and private organizations. To explain the dynamics of open source projects, this research theoretically identified and empirically analyzed a construct – attractiveness – found crucial to them due to its influence on how they are populated and operate, subsequently impacting the qualities of the software produced and of the support provided. Both attractiveness\u27 causes and consequences were put under scrutiny, as well as its indicators. On the side of the consequences, it was theoretically proposed and empirically tested whether the attractiveness of these projects affects their levels of activeness, efficiency, likelihood of task completion, and time for task completion, though not linearly, as task complexity could moderate the relationships between them. Also, it was argued at the theoretical level that activeness, efficiency, likelihood of task completion, and time for task completion mediate the relationship between attractiveness and software/support quality. On the side of attractiveness\u27 causes, it was proposed and tested that five open software projects\u27 characteristics (license type, intended audience, type of project and project’s life-cycle stage) impact attractiveness directly. Additionally, these projects\u27 characteristics were argued to influence projects\u27 levels of activeness, efficiency, likelihood of task completion, and time for task completion (and so an empirical evaluation of their associations was performed). The empirical tests of all these relationships between constructs were carried out using Structural Equation Modeling with Maximum Likelihood on three samples of over 4,600 projects each, collected from the largest repository of open source software, Sourceforge.net (a repeated cross-sectional approach). The results confirmed the importance of attractiveness, suggesting a direct influence on projects\u27 dynamics, as opposed to the moderated-by-task complexity indirect paths first proposed. Furthermore, all four projects\u27 characteristics studied were found to significantly influence projects\u27 attractiveness, activeness, efficiency, likelihood of task completion, and time for task completion (with the exception of license type and time for task completion). Besides providing a statistical test of these propositions, this study discovered the direction of the influence of each project characteristic on projects\u27 attractiveness, activeness, efficiency, likelihood of task completion and time for task completion. Lastly, conclusions, limitations, and future directions are discussed based on these findings

Demand, supply and markup fluctuations

Markup cyclicality has been central for debating policy effectiveness and understanding business cycle fluctuations. However, there are two empirical challenges: separating supply (TFP) from demand shocks, and properly measuring the markups. In this article, we use a panel of Portuguese manufacturing firms for 2004-2014. Since it contains information on product- level prices, we can separate supply from demand shocks. We overcome the markup measurement by using the share of intermediate inputs on revenues, instead of the labor share. Our results suggest that markups are pro-cyclical with TFP shocks, and counter-cyclical with demand shocks. We also show that labor-based markups are pro-cyclical.info:eu-repo/semantics/publishedVersio

Reductive decarboxylation of bicyclic prolinic systems: a new approach to the enantioselective synthesis of the Geissman-Waiss lactone. X-ray structure determination of a key lactone intermediate

Two concise and enantioselective syntheses of the necine base precursors (1R,5R)-N-Cbz and N-Boc-2-oxa-6-azabicyclo[3.3.0]octan-3-ones (Geissman-Waiss lactones) were carried out from two enantiomerically pure endocyclic five-membered enecarbamates with overall yields of 23% and 26%, respectively. The synthetic strategy made use of a highly effective and stereoselective [2+2]cycloaddition of enantiomerically pure endocyclic enecarbamates with dichloroketene, as well as an efficient decarboxylation step of a bicyclic alpha-amino acid employing Boger's acyl selenide protocol employing tributyltin hydride. Interesting aspects concerning the regiochemical outcome of Baeyer-Villiger oxidations of bicyclic cyclobutanones are also reported, in which the usual stereoelectronic bias of Baeyer-Villiger oxidation seems to be counterbalanced by steric effects on the putative Criegee intermediate.Duas sínteses do conhecido precursor de bases necínicas, (1R,5R)-N-Cbz e N-Boc 2-oxa-6-azabiciclo[3.3.0]octan-3-onas (lactonas de Geissman-Waiss) foram realizadas com rendimentos globais de 23% e 26%, em seis e cinco etapas respectivamente, a partir de enecarbamatos endocíclicos de cinco membros enantiomericamente puros. A estratégia sintética adotada está fundamentada em uma reação de cicloadição [2+2] eficiente e altamente estereosseletiva de enecarbamatos de cinco membros com diclorocetenos, assim como em uma eficaz descarboxilação de alfa-amino ácidos bicíclicos pelo método de Boger, que utiliza a redução de selenetos de acila por hidretos de estanho. Aspectos relativos a regiosseletividade da reação de oxidação de azabiciclo ciclobutanonas pelo método de Baeyer-Villiger são também descritos, com destaque para um potencial controle regioquímico advindo de aspectos estéreos em contraposição a aspectos estereoeletrônicos.2738Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

The use of interdital areas by foraging waders:constraints on the exploitation of food resources

Tese de doutoramento, Biologia (Ecologia), 2009, Universidade de Lisboa, Faculdade de CiênciasDisponível no documentoFundação para a Ciência e a Tecnologia (SFRH/BD/16991/2004) and the research projects POCTI/BSE/47569/2002 and PTDC/MAR/66319/2006

Estudo da resposta de um dosímetro eletrónico individual

Introdução – A monitorização da exposição ocupacional a doses de radiação ionizante pode ser complementada por dosímetros eletrónicos individuais que permitem uma leitura direta da dose de radiação recebida. Dada a dependência energética e de débito de dose já reportada para estes dosímetros, este trabalho pretende determinar a linearidade da resposta de um dosímetro eletrónico individual e estudar o comportamento da sua resposta em função da energia de radiação e do débito de dose. Metodologia – Para estudar a dependência da energia da radiação do dosímetro eletrónico pessoal Vertec Bleeper Sv procedeu‑se à sua irradiação com um equivalente de dose individual, Hp(10), de 500 μSv de radiação gama do Cobalto – 60 (60C) e Césio – 137 (137Cs) e das qualidades de radiação X da série Narrow (N): N‑30, N‑40, N‑60, N‑80, N‑100 e N‑120. Para investigar a dependência da resposta em função do débito de dose aplicaram‑se à ampola de raios X as intensidades de corrente elétrica de 1 mA, 5 mA, 10 mA, 15 mA e 20 mA. Resultados – Não existe uma relação entre a resposta do detetor e a energia de radiação a que este é exposto. Ocorre uma subestimação superior a 50% na grandeza medida para energias inferiores a 33 keV, mas ostenta uma medida relativamente linear da grandeza Hp(10) para doses inferiores a 100 μSv. Também se constata que, à medida que o débito de dose aumenta, existe uma diminuição na resposta do dosímetro. O menor decréscimo na resposta deste dosímetro eletrónico individual dá‑se para as qualidades de radiação N‑30 (1,1%), N‑40 (4,1%) e N‑120 (20,0%). Conclusão – Verifica‑se que a resposta do dosímetro individual Vertec Bleeper Sv depende fortemente da energia da radiação e do débito de dose. ABSTRACT: Introduction – The measurement of occupational exposure to radiation doses can be completed with an electronic personal dosemeter that allows a direct reading and alarm function of the received radiation dose. Due to the energy and dose rate dependence already reported for this type of dosemeter, it is intended, with this work, to determine the response linearity of an Electronic Personal Dosemeter and to study its response behavior to the dose rate and radiation energy. Methodology – The electronic personal dosemeter Vertec Bleeper Sv energy dependency was evaluated by its irradiation with 500 μSv from the radionuclides Cobalt – 60 (60C) and Cesium – 137 (137Cs) as well as by the radiation qualities of the Narrow (N) series: N‑30, N‑40, N‑60, N‑80, N‑100 e N‑120. To investigate the dose rate dependency, the intensities of electric current of 1 mA, 5 mA, 10 mA, 15 mA and 20 mA were applied to the X‑ray tube. Results – There is no relationship between the response of the detector and the radiation energy. For energies below 33 keV there is an underestimation over 50% of the radiation dose measured but the detector presents a linear response for energies under 100 μSv. A dependency on the dose rate is perceived since as the dose rate increases, the response of the individual monitor decreases. There is a smaller decrease for the radiation qualities of N‑30 (1.1%), N‑40 (4.1%) and N‑120 (20.0%). Conclusion – It is concluded that there is a strong dependence of radiation energy and dose rate on the response of an electronic personal dosemeter

Actomyosin modulation by peroxynitrite

In the present work we address the oxidative modifications accounting for the structural and functional impairment of the actomyosin complex under the oxidative stress mediated by peroxynitrite (ONOO-). Experiments on purified myosin and actin have shown that submicromolar ONOO- concentrations produce strong inhibition of the F-actin stimulated myosin ATPase activity. The peroxynitrite-induced actomyosin impairment correlated with structural modifications that decrease the thermal stability of both actin and myosin leading to partially unfolded states. The results suggest a major role for the highly reactive cysteines on actin and on myosin and also for some critical methionines on G-actin. 3-nitrotyrosine does not contribute significantly to the observed functional alterations

Study of the detection efficiency of a surface contamination monitor according to the distance and the surface emission rate

Introdução – No caso de uma eventual contaminação radioativa esta deve ser quantificada, pelo que é necessário garantir que as condições de funcionamento de um monitor de contaminação de superfícies se encontrem adequadamente caracterizadas, através da determinação da sua eficiência de deteção. Este estudo tem como objetivo determinar a eficiência de deteção de um monitor de contaminação e analisar a influência da distância e da atividade. Metodologia – O monitor de contaminação Thermo Mini 900E e as fontes radioativas planas de referência de Carbono – 14 (C-14), Césio – 137 (Cs-137), Estrôncio – 90 (Sr-90), Cloro – 36 (Cl-36) e Amerício – 241 (Am-241) com débito de emissão superficial rastreável ao Physikalish Technischen Bundesanstalt (PTB) foram utilizadas. Fontes de Sr-90 e C-14 com dois débitos de emissão distintos para cada e distâncias de 1 a 20mm foram usados para estudar a sua influência na eficiência de deteção. Resultados – Verificou-se que as fontes radioativas emissoras de partículas de maior energia apresentam uma maior eficiência de deteção e que esta diminui com o aumento da distância do detetor à fonte, sendo que os radioisótopos de maior energia apresentam um decréscimo na eficiência de 15% ao longo de 20mm, enquanto os radioisótopos de menor energia apresentam um decréscimo de 10%. Não se verificou uma influência expressiva do débito de emissão na eficiência de deteção deste monitor de contaminação. Conclusão – A eficiência de deteção de um monitor de contaminação portátil é dependente da distância deste à contaminação bem como do tipo de radiação emitida e energia dos radioisótopos presentes na contaminação. - ABSTRACT - Introduction – A radioactive contamination needs to be quantified in case it eventually occurs. Therefore it is necessary to ensure that the operating conditions of a surface contamination monitor are characterized by determining its detection efficiency. This experimental study aims to determine the detection efficiency of a contamination monitor and evaluate the distance and surface emission rate influence on the detection efficiency. Methodology – A contamination monitor Thermo Mini 900E was tested with reference radiation sources of Carbon – 14 (C-14), Cesium – 137 (Cs-137), Strontium – 90 (Sr-90), Chlorine – 36 (Cl-36) and Americium – 241 (Am-241) with its emission rate traced to the Physikalish Technischen Bundesanstalt (PTB). Sources of Sr-90 and C-14 with two different emission rates for each one and distances of 1 to 20mm were used to study its influence in the detection efficiency. Results – With the increasing of distance, the detection efficiency decreases. The most energetic radiation sources have higher detection efficiency, boasting a 15% decrease over 20mm whereas the sources bearing a smaller efficiency decrease 10%. No influence of the surface emission rate in the detection efficiency was verified. Conclusion – Thus, it is concluded that the detection efficiency of a contamination monitor is dependent of the distance between it and the contamination as well as the type and energy of the radioisotopes present in the contamination

Global changes in coastal wetlands of importance for non-breeding shorebirds

Shorebird declines are occurring worldwide but the causes are not fully understood. Recent literature suggests that the deterioration of habitat quality at their non-breeding areas, mostly located in temperate and tropical coastal wetlands, might be a major contributing factor. However, most studies carried out so far tend to be restricted to a few regions. Remote sensing can help correct such geographical bias on knowledge by providing a standardized approach on how shorebird habitats have been changing over the last few decades at a global scale. Here we analyzed time series of remote sensing classifications of tidal flats and land cover to quantify worldwide habitat changes in coastal Important Bird and Biodiversity Areas (IBAs) relevant for non-breeding shorebirds over the last two decades. Globally, supratidal areas (used as roosting habitat) have changed more significantly than tidal flats (used as feeding habitat). Yet, we found striking losses of tidal flats in IBAs distributed in several regions of the East Asian - Australasian Flyway. At supratidal areas, there was a general expansion of marshland, grassland and urban areas, contrasting with a decline of barren land, woodland and cropland. The expansion of marshland occurred in IBAs of most regions of the world. Urban areas also expanded consistently in supratidal areas within the most populated regions of the world. The loss of barren land is particularly concerning as it may translate into a loss of high-quality roosts and it was highly frequent in IBAs of all migratory flyways. Overall, our results confirm the large losses of shorebird habitat in the East Asian - Australasian Flyway reported in the literature, and highlight unreported generalized changes in supratidal habitats, such as the expansion of marshland and the loss of barren land, that may have negative implications for shorebirds, deserving further research and consideration in conservation programs.info:eu-repo/semantics/publishedVersio

Endoscopic endonasal ligation of the esphenopalatine artery for severe epistaxis

Introduction: Severe epistaxis, usually associated to hypertension and blood dyscrasia, may benefit from surgery when the conservative treatment fails. Aim: to evaluate the results of endoscopic endonasal ligation of the sphenopalatine artery for non-responsive severe epistaxis. Study design: Clinical prospective. Material and Method: chart review of twelve patients submitted to endoscopic endonasal ligation of the sphenopalatine artery regarding clinical aspects, predisposing factors and complications of the procedure. Results: the mean age was 50.9 years, and the male:female: ratio was 2:1. Hypertension was presented in 33% and hematologic disorders in 16.6% of the patients. One patient, 8.3%, presented a new bleeding episode after the surgery. Discussion: the endoscopic endonasal ligation of the sphenopalatine artery, proved to be a safe surgical method and presented 8.3% of bleeding after the procedure in our study. Conclusion: avoiding the complications of previous surgical treatments for severe epistaxis, the endoscopic endonasal ligation of the sphenopalatine artery is an effective technique affordable for otolaryngologists with practice in endoscopic endonasal surgery.Introdução: A epistaxe severa, geralmente associada a fatores predisponentes como hipertensão arterial sistêmica e coagulopatia, é uma doença desafiadora, e pode necessitar de uma abordagem cirúrgica nos casos que não respondem ao tratamento conservador, como cauterização e tamponamento nasal. Objetivo: avaliar os resultados da ligadura endoscópica endonasal da artéria esfenopalatina no tratamento da epistaxe severa refratária à abordagem terapêutica conservadora. Forma de estudo: Clínico prospectivo. Material e Método: foram avaliados doze casos de pacientes submetidos à ligadura endoscópica endonasal da artéria esfenopalatina no tratamento da epistaxe severa não responsiva ao tratamento conservador, observando-se a história clínica, os fatores predisponentes, a evolução e as complicações deste procedimento. Resultados: a idade média foi de 50,9 anos, e a distribuição por sexo foi de 33% do sexo feminino e 67% do sexo masculino; 33% apresentaram HAS e 16,6% coagulopatia (hepatopatia) como fatores predisponentes. Um paciente (8,3%) apresentou ressangramento após o procedimento cirúrgico. Discussão: a ligadura endoscópica endonasal da artéria esfenopalatina representa uma abordagem segura e garante um controle satisfatório do sangramento, com índice de ressangramento de 8,3% entre os nossos casos. Conclusão: a ligadura endoscópica endonasal da artéria esfenopalatina representa uma opção cirúrgica adequada, pois não apresenta as complicações das técnicas anteriores, atinge um controle satisfatório do sangramento e pode ser realizada por otorrinolaringologistas habituados à cirurgia endoscópica nasal.Universidade Federal de São Paulo (UNIFESP) Escola Paulista de MedicinaUniversidade Federal de São Paulo (UNIFESP) Escola Paulista de Medicina Setor de RinologiaUNIFESP, EPM, Setor de RinologiaSciEL