The chikungunya virus (CHIKV) is a mosquito‐transmitted alphavirus, which has infected millions of people in Africa, Asia, Americas, and Europe since it remerged in India and Indian Ocean regions in 2005–2006. The purpose of this study was to evaluate the genetic diversity and evolutionary changes in CHIKV from 2016 to 2018 in Pakistan. Blood specimens were collected and processed following the Centers for Disease Control and Prevention Trioplex Protocol. Sequencing and phylogenetic analysis of complete coding sequence of representative isolates from the CHIKV outbreak was carried out during December 2016 to July 2018, a total of 1549 samples were received, out of which 50% (n = 774) were found positive for CHIKV RNA. Mean age of chikungunya positive patients was 31.8 ± 15.7 years and most affected were between 21 and 40 years of age. The Pakistan CHIKV strains clustered with the Indian Ocean sublineage of East/Central/South African with cocirculation of some variants In the structural proteins region, two noteworthy changes (A226V and D284E) were observed in the membrane fusion glycoprotein E1. Key substitutions in the neutralizing epitopes site and a few changes indicative of adaptive to other insect cells were also detected in Pakistani strains. This study provides the emerging trend of CHIKV in the country for early identification of potential variants of high virulence and preventive measures for vector borne disease especially in the endemic areas.
This paper describes the influence of deformation by equal-channel angular pressing (ECAP) on the solid particle erosion resistance of the AlSi7Mg0.3 alloy and AlSi7Mg0.3 based composite material reinforced with the addition of 4 % of fly ash (FA) particles. Both, alloy and composite samples were produced using the compo-casting method. The samples have been subjected to ECAP in multiple passes with the rotation of samples around the vertical axis for the angle of 90° after each pass. Particles of silicon carbide (SiC) have been used as erodent while their impact angle was varied (30° and 90°). Observed samples of AlSi7Mg0.3 alloy generally showed higher wear resistance at 90° angle where material fatigue predominates, than at a 30° angle where abrasion-related phenomena predominate. On the other hand, AlSi7Mg0.3 based composite material exhibited erosion wear at 30° angle less than at 90° angle after one ECAP pass. Evaluation of the erosion resistance has been made based on mass and volume loss. After two passes of ECAP, the matrix structure of the AlSi7Mg0.3 based composite material, as well as that of the AlSi7Mg0.3 alloy was improved from the aspect of erosion resistance.
Excessive use of pesticides and fertilizers in agriculture in order to increase yields has proved unnecessary because a large part of them remain unused and have negative effects on the environment and human health. Therefore, it is a great challenge for farmers to replace the application of pesticides and fertilizers with nanopesticides and nanofertilizers, with the aim of reducing the use of mineral fertilizers and increasing yields, as well as supporting agricultural development. This review provides a detailed overview of the classification of pesticides, commonly used nanoparticles in agriculture and their function, as well as impact of nanopesticides and nanofertilizers on the environment. The application of nanopesticides and nanofertilizers and new delivery mechanisms to improve crop productivity are reviewed and described. Particularly, the advantage of the nanoencapsulation process is emphasized for both pesticides and fertilizers. For hydrophobic pesticides, it may be a tool to provide greater stability, dispersion in aqueous media, and allowing a controlled release of the active compound, which increases its effectiveness. In nanofertilizers, micro- or macronutrients can be encapsulated by nanomaterials which allow to release of nutrients into the soil gradually and in a controlled way maintaining soil fertility, thus preventing eutrophication and pollution of water resources. Risks assessment of application of nanopesticides and nanofertilizers in agriculture are required for their correct and safe application.
O hiperestrogenismo em cães tem várias etiologias, dentre elas, o resultado da excessiva produção de estrógeno por tumores testiculares ou ovarianos. É descrito também que pode ter origem devido a um desequilíbrio entre os hormônios andrógenos e estrógenos. Como resultado do hiperestrogenismo, manifestam-se dermatoses clínicas como, alopecia bilateral simétrica, pelagem rarefeita, facilmente destacáveis, hiperpigmentação variável. O diagnóstico é baseado no histórico, anamnese, sinais clínicos, ultrassonografia testicular, dosagem hormonal de estrógenos séricos e realização de exame histopatológico. O tratamento de eleição é a orquiectomia. O objetivo do presente estudo é relatar a ocorrência de uma dermatose secundária ao hiperestrogenismo em um cão jovem.
Abstract For years, sustainable tourism has commanded the attention of academics and practitioners given its achievement through participatory planning. However, much research in the area has neglected to consider all voices of those (i.e., children) affected by tourism. This study, employing a post-test only experimental design, addresses this gap by including the voices of 498 children from six diverse European destinations concerning perceptions of tourism. Results show that children are willing to express their opinions given the opportunity. Moreover, their attitude towards tourists is negative, while they perceive locals to hold a subordinate position to tourists. In general, this study offers insight into children’s attitudes to tourism from the host perspective, demonstrating that there is a unique insider’s perspective that needs further research.
Enabling System-of-Systems (SoS) security is an important activity when engineering SoS solutions like autonomous vehicles, provided that they are also highly safety-critical. An early analysis of such solutions caters for proper security architecture decisions, preventing potential high impact attacks and ensuring people's safety. However, SoS characteristics such as emergent behavior, makes security decision-making at the architectural level a challenging task. To tackle this challenge, it is essential to first address known vulnerabilities related to each CS, that an adversary may exploit to realize his attacks within the unknown SoS environment. In this paper we investigate how to use Game Theory (GT) approaches to guide the architect in choosing an appropriate security solution. We formulate a game with three players and their corresponding strategies and payoffs. The proposal is illustrated on an autonomous quarry example showing its usefulness in supporting a security architect to choose the the most suitable security strategy.
This paper presents a novel control algorithm for variable speed wind generators (VSWG), designed to provide support to grid frequency regulation. The proposed control algorithm ensures that VSWG ‘’truly’’ emulates response of a conventional generating unit with non-reheat steam turbine (GUNRST) in the first several seconds after active power unbalance. A systematic method of analysis and synthesis of the new control algorithm is described in detail.
OBJECTIVES The physical activity level (PAL) has significantly decreased as a result of the social distancing and lockdown related to the COVID‑19 pandemic, but there is a lack of knowledge on the correlates of PAL during the pandemic. The aim of this research was to examine the influence of pre-pandemic sports participation and substance use and misuse (SUM) on PAL during the COVID‑19 pandemic. MATERIAL AND METHODS The study included 661 high-school students from Bosnia and Herzegovina (aged 15-18 years, 292 females). The investigation included 2 testing waves: before the COVID‑19 pandemic (baseline, January 2020) and during the COVID‑19 lockdown (follow-up, April 2020). The variables included PAL as measured by the Physical Activity Questionnaire for Adolescents, sports factors, and SUM. RESULTS Sports factors at baseline were positively correlated with PALs at both baseline and follow-up. Smoking tobacco negatively affected PALs at both baseline and follow-up. Alcohol consumption was positively correlated with PAL at baseline but had no effect on PAL at follow-up. CONCLUSIONS This study confirmed the importance of sports participation in maintaining PAL during challenging situations, such as the COVID‑19 lockdown. The substance-specific influence of SUM on PAL before and during the lockdown points to evident social and cultural aspects of SUM behaviors in adolescents. Further studies evidencing the cumulative effects of PAL decline during the lockdown are warranted.
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