210 research outputs found

    Cluster approximation solution of a two species annihilation model

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    A two species reaction-diffusion model, in which particles diffuse on a one-dimensional lattice and annihilate when meeting each other, has been investigated. Mean field equations for general choice of reaction rates have been solved exactly. Cluster mean field approximation of the model is also studied. It is shown that, the general form of large time behavior of one- and two-point functions of the number operators, are determined by the diffusion rates of the two type of species, and is independent of annihilation rates.Comment: 9 pages, 7 figure

    Healthcare Professionals' Views on the Management of Medication Complexities in the Elderly With Mental Health Disorders: A Cross-Sectional Study

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    Background: Many challenges in elderly pharmacotherapy are identified, including the use of Potentially Inappropriate Medications (PIMs) which may increase the odds of adverse events, especially in elderly patients with mental health disorders (e. g., behavioral, and psychological symptoms of dementia–BPSD, schizophrenia, bipolar disorder). However, information on the knowledge and practice of healthcare professionals (HCPs) about this topic is still scarce. Methods: A cross-sectional study was undertaken from July-October 2019. An online questionnaire was specifically designed and validated for this study. We sought HCPs (physicians, pharmacists, and nurses) worldwide, using (a) social media, via Facebook, Twitter, and LinkedIn; and (b) email contacts of the research team (convenience sample). Either way participants were asked to share on their social media or via e-mail the questionnaires with other HCPs (snowballing sample). The survey assessed two main domains: knowledge and practice. Knowledge was evaluated by self-report (perceived knowledge by a 5-item Likert confidence scale) and using three clinical cases, scored between 0 and 30 points (each one rated from 0 to 10 points; real knowledge). Barriers in clinical practice were evaluated using a 5-item Likert scale judging practitioners' opinion. Results: A total of 165 questionnaires were collected. HCPs were mainly female (n = 114; 69.1%), with a mean age of 35.3 ± 11.3 years old. Seventy-two percent (n = 118) were pharmacists, 21.1% (n = 35) were physicians, and 7.3% (n = 12) nurses. There was a weak correlation, albeit significant, between perceived and real knowledge (r = 0.199; p = 0.001). The mean score of the clinical vignettes regarding elderly patients with dementia and bipolar disorder were 4.59 ± 4.08 and 4.86 ± 2.97 points, respectively. Most HCPs were classified as having an intermediate knowledge (n = 100; 60.6%) about medication complexities in the elderly with mental disorders. Most HCPs agreed that lack of time (81.6%; n = 138), lack of education and training on elderly pharmacotherapy (72.2%; n = 122), and lack of tools adapted to daily practice (61.8%; n = 105) were the main barriers. Conclusions: Most of the HCPs felt confident to manage medication complexities in elder patients with mental disorders, but only a minority obtained a good score in the knowledge assessment test. The main barriers identified included structural barriers (tools unfit for practice) and process barriers (time)

    Diversity and patterns of marine non‐native species in the archipelagos of Macaronesia

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    Aims The present study is the first attempt to grasp the scale and richness of marine biological invasions in Macaronesia. We pioneered a comprehensive non-native species (NNS), inventory in the region to determine their diversity patterns and native distribution origins. NNS were defined here as the result of both introductions and range expansions. We also used statistical modelling to examine relationships among NNS richness, anthropogenic activities, demographic and geographical variables across Macaronesia. Location Macaronesia. Methods A comprehensive literature search was conducted for marine NNS records in Macaronesia, registering the first record's location and year from 1884 to 2020. We used univariate and multivariate analyses to evaluate differences and similarities in community composition. By applying a Generalized Linear Model (GLM), we tested hypotheses regarding NNS richness as a function of anthropogenic activities, demographic and geographical variables. Results A total of 144 marine non-native species (NNS) were recorded for the whole of Macaronesia. The highest NNS richness was registered in the Canary Islands (76 NNS), followed by the Azores (66 NNS), Madeira (59 NNS) and finally Cabo Verde (18 NNS). Some differences amongst archipelagos were observed, such as the high number of non-native macroalgae in the Azores, fishes in the Canary Islands and tunicates in Cabo Verde. Overall, macroalgae, tunicates and bryozoans were the predominant taxonomic groups in the Macaronesian archipelagos. Madeira and Canary Islands were the archipelagos with more similarity in marine NNS, and Cabo Verde the most divergent. Finally, GLM suggested that non-native richness patterns across Macaronesia were dependent on the considered archipelago and strongly affected by (1) minimum distance to the mainland, (2) the total number of ports and marinas and (3) total marinas area (km2). Conclusions The model results and NNS listing in the present study will likely raise the awareness and response regarding marine NNS in the whole Macaronesia region, serving as a baseline for future research as well as implementing and enforcing regulations related to the introduction of marine NNS in oceanic islands

    Fusarium wilt incidence and common bean yield according to the preceding crop and the soil tillage system

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    The objective of this work was to evaluate the effects of preceding crops and tillage systems on the incidence of Fusarium wilt (Fusarium oxysporum f. sp. phaseoli) and common bean (Phaseolus vulgaris) yield. The cultivar BRS Valente was cultivated under center‑pivot irrigation in the winter seasons of 2003, 2004 and 2005, after several preceding crops established in the summer seasons. Preceding crops included the legumes Cajanus cajan (pigeon pea), Stylosanthes guianensis, and Crotalaria spectabilis; the grasses Pennisetum glaucum (millet), Sorghum bicolor (forage sorghum), Panicum maximum, and Urochloa brizantha; and a consortium of maize (Zea mays) and U. brizantha (Santa Fé system). Experiments followed a strip‑plot design, with four replicates. Fusarium wilt incidence was higher in the no‑tillage system. Higher disease incidences corresponded to lower bean yields in 2003 and 2004. Previous summer cropping with U. brizantha, U. brizantha + maize consortium, and millet showed the lowest disease incidence. Therefore, the choice of preceding crops must be taken into account for managing Fusarium wilt on irrigated common bean crops in the Brazilian Cerrado

    Portuguese Ministers, 1851-1999: Social Background and Paths to Power

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    Disponível em: http://193.136.113.6/Opac/Pages/Search/Results.aspx?SearchText=UID=bb8aa8d5-c6b6-466a-81bb-fe8a67693cee&DataBase=10449_UNLFCSHThis paper provides an empirical analysis of the impact of regime changes in the composition and patterns of recruitment of the Portuguese ministerial elite throughout the last 150 years. The ‘out-of-type’, violent nature of most regime transformations accounts for the purges in and the extensive replacements of the political personnel, namely of the uppermost officeholders. In the case of Cabinet members, such discontinuities did not imply, however, radical changes in their social profile. Although there were some significant variations, a series of salient characteristics have persisted over time. The typical Portuguese minister is a male in his midforties, of middle-class origin and predominantly urban-born, highly educated and with a state servant background. The two main occupational contingents have been university professors - except for the First Republic (1910-26) - and the military, the latter having only recently been eclipsed with the consolidation of contemporary democracy. As regards career pathways, the most striking feature is the secular trend for the declining role of parliamentary experience, which the democratic regime did not clearly reverse. In this period, a technocratic background rather than political experience has been indeed the privileged credential for a significant proportion of minister
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