Linear Theory of Electron-Plasma Waves at Arbitrary Collisionality

The dynamics of electron-plasma waves are described at arbitrary collisionality by considering the full Coulomb collision operator. The description is based on a Hermite-Laguerre decomposition of the velocity dependence of the electron distribution function. The damping rate, frequency, and eigenmode spectrum of electron-plasma waves are found as functions of the collision frequency and wavelength. A comparison is made between the collisionless Landau damping limit, the Lenard-Bernstein and Dougherty collision operators, and the electron-ion collision operator, finding large deviations in the damping rates and eigenmode spectra. A purely damped entropy mode, characteristic of a plasma where pitch-angle scattering effects are dominant with respect to collisionless effects, is shown to emerge numerically, and its dispersion relation is analytically derived. It is shown that such a mode is absent when simplified collision operators are used, and that like-particle collisions strongly influence the damping rate of the entropy mode.Comment: 23 pages, 10 figures, accepted for publication on Journal of Plasma Physic

The ionizing sources of luminous compact HII regions in the RCW106 and RCW122 clouds

Given the rarity of young O star candidates, compact HII regions embedded in dense molecular cores continue to serve as potential sites to peer into the details of high-mass star formation. To uncover the ionizing sources of the most luminous and compact HII regions embedded in the RCW106 and RCW122 giant molecular clouds, known to be relatively nearby (2-4 kpc) and isolated, thus providing an opportunity to examine spatial scales of a few hundred to a thousand AU in size. High spatial resolution (0.3"), mid-infrared spectra (R=350), including the fine structure lines [ArIII] and [NeII], were obtained for four luminous compact HII regions, embedded inside the dense cores within the RCW106 and RCW122 molecular cloud complexes. At this resolution, these targets reveal point-like sources surrounded by nebulosity of different morphologies, uncovering details at spatial dimensions of <1000AU. The point-like sources display [ArIII] and [NeII] lines - the ratios of which are used to estimate the temperature of the embedded sources. The derived temperatures are indicative of mid-late O type objects for all the sources with [ArIII] emission. Previously known characteristics of these targets from the literature, including evidence of disk or accretion suggest that the identified sources may grow more to become early-type O stars by the end of the star formation process

Crafting a Systematic Literature Review on Open-Source Platforms

This working paper unveils the crafting of a systematic literature review on open-source platforms. The high-competitive mobile devices market, where several players such as Apple, Google, Nokia and Microsoft run a platforms- war with constant shifts in their technological strategies, is gaining increasing attention from scholars. It matters, then, to review previous literature on past platforms-wars, such as the ones from the PC and game-console industries, and assess its implications to the current mobile devices platforms-war. The paper starts by justifying the purpose and rationale behind this literature review on open-source platforms. The concepts of open-source software and computer-based platforms were then discussed both individually and in unison, in order to clarify the core-concept of 'open-source platform' that guides this literature review. The detailed design of the employed methodological strategy is then presented as the central part of this paper. The paper concludes with preliminary findings organizing previous literature on open-source platforms for the purpose of guiding future research in this area.Comment: As presented in 10th IFIP WG 2.13 International Conference on Open Source Systems, OSS 2014, San Jos\'e, Costa Rica, May 6-9, 201

Thermal comfort evaluation of an operating room through CFD methodology

Different studies have been evidencing that the surgeon, working with a high metabolic rate, feels uncomfortable after a time. This enforces the study of indoor thermal conditions in health care facilities. The main objective of the present work is the evaluation of the thermal comfort sensation experienced by surgeons and nurses inside a Portuguese orthopaedic surgical room, using the PMV index. Through CFD tools and a post-processing routine, it was obtained the PMV index in each domain node, in opposite to the typical use of average climate values. The use of average ventilation values, to calculate the index, does not provide a correct and enough descriptive evaluation of the surgical room thermal environment. It is noticeable that surgeons and nurses feel different thermal sensations in the same surgical room. For the studied case, the surgeon feels the room environment hotter than the nurse. The nurses feel a slightly cold sensation under the air supply diffuser and a neutral zone is located in the air stagnation zones close to the walls. As expected for both cases, lamps provide an uncomfortable sensation. The clothing used by both classes, as well as the ventilation conditions, shall be revised accordingly to the amount of persons in the room and the type of activity performed

Biodiversidade de actinobactérias do solo da caatinga para controle biológico de pragas.

Resumo: Actinobactérias são bactérias gram-positivas e constituem boa parte da população microbiana do solo. Este trabalho teve como objetivo estudar as actinobactérias do solo do Bioma Caatinga, a fim de descobrir espécies que forneçam controle biológico dos fungos Pyricularia grisea e Pythium aphanidermatum, responsáveis por causar doenças em plantas. Do total de isolados obtidos, 14 obtiveram resultado no controle destes fungos, e 2 já foram identificados. Destes 2, um apresenta-se como provável espécie nova, e está sendo objeto de estudo aprofundado. Este trabalho mostra como é importante preservar a Caatinga, pois no seu solo vivem microrganismos que podem ser capazes de desempenhar resultados positivos tanto na agricultura quanto na indústria. Abstract: Actinomycetes are gram-positive bacteria and constitute a large part of the soil microbial population. This work aims to study the soil actinomycetes from the Caatinga, in order to discover species that provide biological control of Pyricularia grisea and Pythium aphanidermatum, fungi responsible for causing diseases in plants. Of the total isolates, 14 obtained result in control of these fungi, and 2 have been identified. Of these two, one is presented as probable new species, and is being studied depth. This work shows how important it is to preserve the Caatinga, as in its soil lives microorganisms that might be able to perform positive results in both agriculture and industry

Third mission activities: university managers' perceptions on existing barriers

In the context of increased international competition and financial austerity, an economic development mission has become an important strategic and policy issue for European higher education. This paper aims to contribute to knowledge regarding universities’ engagement with the external environment and its impact on internal governance and management. Using a qualitative case study approach, the paper explores third mission activities in Portuguese universities and examines university managers’ perceptions about the barriers to their greater effectiveness. The results identified two major types of barriers: external, relating mainly to government regulations and funding allocation, and internal, involving organisational characteristics. The study also highlighted some tensions between a growing emphasis on third mission activities and their institutionalization process within universities. The results are relevant to researchers who would like to continue the debate in a comparative perspective; as well as to policymakers and institutional leaders.info:eu-repo/semantics/publishedVersio

Evaluation of Microencapsulation of The UFV-AREG1 Bacteriophage in Alginate-Ca Microcapsules using Microfluidic Devices

The indiscriminate use of antibiotics and the emergence of resistant microorganisms have become a major challenge for the food industry. The purpose of this work was to microencapsulate the bacteriophage UFV-AREG1 in a calcium alginate matrix using microfluidic devices and to study the viability and efficiency of retention. The microcapsules were added to gel of propylene glycol for use as an antimicrobial in the food industry. The technique showed the number of the phage encapsulation, yielding drops with an average 100-250 $\mu$m of diameter, 82.1 $\pm$ 2% retention efficiency and stability in the gel matrix for 21 days. The gel added to the microencapsulated phage showed efficiency (not detectable on the surface) in reducing bacterial contamination on the surface at a similar level to antimicrobial chemicals (alcohol 70%). Therefore, it was possible to microencapsulate bacteriophages in alginate-Ca and apply the microcapsules in gels for use as sanitizers in the food industry.Comment: 8 pages, 5 figure

Individual actors and embeddedness in business-to-business interactions

Individual actors are hardly ever considered in business-to-business marketing literature. This paper uses Service-dominant Logic and Neo-institutional Theory as the bases for twelve case studies. These case studies provide a better understanding of how individuals who represent firms make sense of the social rules, norms, procedures, values, and beliefs of the network (i.e. institutional logics) where they are embedded and how the business interaction is shaped by those influences, through the individual behaviour. This paper makes two main contributions. First, we develop an empirical model of how individuals consider the institutional logics of the network in interactions with suppliers. Second, we present three patterns of individual behavior in interactions, different from what is often assumed by business-to-business researchers. Managerial contributions are also pointed out.info:eu-repo/semantics/acceptedVersio