126 research outputs found
Trends and biases in the scientific literature on Brazilian watersheds
Brazilian watersheds have a high species and natural resources biodiversity. To know the features of scientific production on these regions is important to adjust study focus and to determine publication biases. This study aims at characterizing the scientific literature about Brazilian watersheds on scientometric grounds. For this purpose, we performed a search of articles in the ISI Web of Science database of the Institute for Scientific Information (ISI). The search returned 2,945 articles: 1,613 on the Amazon basin, 584 on the La Plata basin, 262 on the São Francisco basin, 190 on the Tocantins basin, 117 on the Southeast Coastal basin, 70 on the Eastern Northeast Coastal basin, 48 on the Parnaíba basin, 45 on the South Coastal basin, 14 on the North Coastal basin and two on the Western Northeast Coastal basin. The highest number of articles, journal diversity and impact factor was for the Amazon basin. Generally, the increase of the number of articles on the coastal basins over the years is lower. A keyword analysis shows that the study of most basins deals with similar subjects. However, researches on the Amazon and La Plata basins follow lines that are very different both from each other and from the other basins. In view of such results, incentives for new studies must focus on coastal basins. It is also recommended to submit works to good quality journals
The Propensity And Intensity Of Export Activities Of Companies Operating In Europe
Previous studies have explored the substantial benefits for companies and governments of exporting. Nevertheless the role of government has been analysed mainly trough export promotion programs and the importance of the subsidiaries of multinational companies to increment a country exports has not been tested together with other variables present in the literature on export performance. This research examines the export performance of companies in Europe. A sample of 239 companies in 12 countries was analysed and their level of exports was examined, using Logit and Tobit models. The contextual variables of the country of operations were combined with company characteristics, including dimension, age, and industry affiliation. The results show that foreign affiliation, age, country of operations and industry are important and that government efficiency is a key element to companies’ propensity and intensity of export
1-Aryl-3-[4-(thieno[3,2-d]pyrimidin-4-yloxy)phenyl]ureas as potential inhibitors of VEGFR-2: synthesis and molecular modelling studies
Angiogenesis is a requirement for tumor growth and metastasis and occurs through several signalling pathways. One key pathway that initiates proliferation and migration of endothelial cells is signalling through the vascular endothelial growth factor receptor-2 (VEGFR-2).1 Therefore, small molecules that block this signalling pathway through inhibition of the VEGFR tyrosine kinase activity could potentially inhibit angiogenesis and tumour growth. Recently works describing thienopyrimidines2 and thienopyridine ureas3 as inhibitors of VEGFR-2 have appeared in the literature. Here we present the synthesis of new 1,3-diarylureas 2 starting by regioselective nucleophilic substitution of the 4-chlorothieno[3,2-d]pyrimidine with 4-aminophenol to obtain 4-(thieno[3,2-d]pyridin-4-yloxy)aniline 1 which reacts with different arylisocyanate
1-aryl-3-(4-(7-methylthieno[3,2-d]pyrimidin-4-yloxy)phenyl)ureas: synthesis and molecular modelling studies using VEGFR-2
The development of anticancer drugs inhibiting angiogenesis has been an area of extensive research in the past decade. Angiogenesis is a requirement for tumor growth and metastasis and occurs through several signalling pathways. One key pathway that initiates proliferation and migration of endothelial cells is signalling through the vascular endothelial growth factor receptor-2 (VEGFR-2).1 Therefore, small molecules that block this signalling pathway through inhibition of VEGFR-2 tyrosine kinase activity could potentially inhibit angiogenesis and tumor growth. Recently works describing thienopyrimidine2 and thienopyrimidine 1,3-diarylureas3 as VEGFR-2 inhibitors have emerged in the literature. Here we present the synthesis of new 1-aryl-3-(4-(7-methylthieno[3,2-d]pyrimidin-4-yloxy)phenyl)ureas 2 in high yields by reaction of 4-[(7-methylthieno[3,2-d]pyridin-4-yl)oxy]aniline 1 with arylisocyanates. The former was prepared by regioselective nucleophilic substitution of 4-chloro-7-methylthieno[3,2-d]pyrimidine with 4-aminopheno
Tendências e lacunas da literatura científica sobre o bioma Cerrado: uma análise cienciométrica
The Cerrado (Brazilian savanna) is the second largest Brazilian biome and is considered a biodiversity hotspot, for presenting high endemism and being under intense threat. This study aimed at highlighting publication trends on the Cerrado, detecting possible gaps and indicating future directions for scientific studies on this biome. We searched for articles between 1991 and 2012 in the journal database of the Institute for Scientific Information (ISI). We observed a significant increase in the number of articles throughout the years of the evaluated period (r=0.89; P<0.001), demonstrating an increasing interest of the scientific community in the Cerrado. Largely addressed issues were related to biodiversity (64.75%), followed by abiotic environment (13.38%) and agricultural crops (11.21%). In addition, 10.65% addressed both biodiversity and abiotic environment jointly. The most studied taxonomic group was plants (42%), followed by fungi (18%) and insects (12%). Fishes presented a lower number of studies (0.6%). The main gaps concern the few studies dealing with abiotic aspects and freshwater organisms, such as fishes, and also a low increment in the number of articles on invertebrates, except insects. Based on these gaps, we suggest that future studies must be especially directed towards aquatic environments and their biodiversity.Keywords: biodiversity, hotspot, scientometrics.O Cerrado (Savana brasileira) é o segundo maior bioma brasileiro, sendo considerado um hotspot de biodiversidade, pois apresenta elevado endemismo e está sob intensa ameaça. O objetivo deste trabalho foi destacar as tendências das publicações sobre o Cerrado, detectar possíveis lacunas e indicar direções futuras para trabalhos científicos nesse bioma. Foi realizada uma busca de artigos utilizando-se a base de periódicos do Institute for Scientific Information (ISI), entre os anos de 1991 a 2012. Foi observado um aumento significativo de artigos ao longo dos anos (r=0,89; P<0,001), demonstrando aumento de interesse da comunidade científica sobre o Cerrado. Grande parte dos trabalhos aborda assuntos relacionados à biodiversidade (64,75%), seguida do meio abiótico (13,38%) e de culturas agrícolas (11,21%). Além disso, 10,65% desses trabalhos abordam os temas biodiversidade e meio abiótico conjuntamente. O grupo taxonômico mais estudado foi o das plantas (42%), seguido de fungos (18%) e insetos (12%). Os peixes apresentaram um menor número de estudos (0,6%). As principais lacunas detectadas estiveram relacionadas a aspectos abióticos e organismos límnicos, como, por exemplo, peixes, bem como um baixo incremento no número de artigos enfocando invertebrados, excetuando-se os insetos. Assim, sugere-se que futuros estudos sejam direcionados principalmente aos ecossistemas aquáticos e sua biodiversidade.Palavras-chave: biodiversidade, cienciometria, hotspot
Análise do efeito imunomodulador da prática de atividade física frente ao COVID-19 / Analysis of the immunomodulatory effect of physical activity against COVID-19
A pandemia originada com o surgimento de uma doença respiratória viral denominada Doença do Novo Coronavírus em 2019 (COVID-19) tornou claro que, apesar das medidas de higiene em saúde coletiva e isolamento social impostas pelos órgãos de saúde, fatores como a capacidade de defesa imunológica do hospedeiro são de suma importância na análise da eficácia de medidas para o controle da contaminação popular. Assim sendo, a prática regular de atividade física de moderada intensidade se mostra crucial no aprimoramento do sistema imune em defesa ao Coronavírus. Sua capacidade de estimular uma resposta celular de padrão predominantemente anti-inflamatório (com predomínio essencialmente da interleucina 6 e 10) e modular a distribuição, fenótipo e atuação dos macrófagos e leucócitos no combate do patógeno está diretamente relacionada com a menor chance de contaminação não somente pelo coronavírus, mas também por infecções virais como influenza. Desta forma, a recomendação da prática de pelo menos 150 minutos por semana de atividade física moderada se torna uma das medidas de auxílio na prevenção da contaminação pelo COVID-19 ao promover bom padrão global de saúde e aprimorar a defesa imunológica do indivíduo
Comparative Effectiveness of COVID-19 Vaccines in Preventing Infections and Disease Progression from SARS-CoV-2 Omicron BA.5 and BA.2, Portugal
We estimated comparative primary and booster vaccine effectiveness (VE) of SARS-CoV-2 Omicron BA.5 and BA.2 lineages against infection and disease progression. During April-June 2022, we implemented a case-case and cohort study and classified lineages using whole-genome sequencing or spike gene target failure. For the case-case study, we estimated the adjusted odds ratios (aORs) of vaccination using a logistic regression. For the cohort study, we estimated VE against disease progression using a penalized logistic regression. We observed no reduced VE for primary (aOR 1.07 [95% CI 0.93-1.23]) or booster (aOR 0.96 [95% CI 0.84-1.09]) vaccination against BA.5 infection. Among BA.5 case-patients, booster VE against progression to hospitalization was lower than that among BA.2 case-patients (VE 77% [95% CI 49%-90%] vs. VE 93% [95% CI 86%-97%]). Although booster vaccination is less effective against BA.5 than against BA.2, it offers substantial protection against progression from BA.5 infection to severe disease.The acquisition of sequencing equipment and reagents used
in this study by the Instituto Nacional de Saúde Doutor
Ricardo Jorge was partially funded by the HERA project
(grant no. 2021/PHF/23776) supported by the European
Commission through the European Centre for Disease
Control, and also partially funded by the GenomePT
project (grant no. POCI-01-0145-FEDER-022184), supported
by COMPETE 2020–Operational Programme for
Competitiveness and Internationalisation, Lisboa Portugal Regional Operational Programme, Algarve
Portugal Regional Operational, under the Portugal 2020
Partnership Agreement, through the European Regional
Development Fund, and by the Portuguese Science and
Technology Foundation. Algarve Biomedical Center
Laboratory received public funding through the Project
ALG-D2-2021-06 Variants Screen in Southern Portugal–
Monitoring Variants of Concern in Southern Portugal and
the Portuguese Science and Technology Foundation
national support through the Comprehensive Health
Research Center (grant no. UIDP/04923/2020)info:eu-repo/semantics/publishedVersio
The Genetics Behind an Emerging Cardiovascular Risk Marker
Publisher Copyright: © The Author(s) 2021.Evidence points epicardial adipose tissue (EAT) as an emerging cardiovascular risk marker. Whether genetic polymorphisms linked with atherosclerosis are associated with higher EAT is still unknown. We aim to assess the role of genetic burden of atherosclerosis and its association to EAT in a cohort of asymptomatic individuals without coronary disease. A total of 996 participants were prospectively enrolled in a single Portuguese center. EAT volume was measured by Cardiac Computed Tomography and participants were distributed into 2 groups, above and below median EAT. SNPs were genotyped and linked to their respective pathophysiological axes. A multiplicative genetic risk score (mGRS) was constructed, representing the genetic burden of the studied SNPs. To evaluate the association between genetics and EAT, we compared both groups by global mGRS, mGRS by functional axes, and SNPs individually. Individuals above-median EAT were older, had a higher body mass index (BMI) and higher prevalence of hypertension, metabolic syndrome, diabetes, and dyslipidemia. They presented higher GRS, that remained an independent predictor of higher EAT volumes. The group with more EAT consistently presented higher polymorphic burden across numerous pathways. After adjustment, age, BMI, and mGRS of each functional axis emerged as independently related to higher EAT volumes. Amongst the 33 SNPs, MTHFR677 polymorphism emerged as the only significant and independent predictor of higher EAT volumes. Patients with higher polymorphism burden for atherosclerosis present higher EAT volumes. We present the first study in a Portuguese population, evaluating the genetic profile of EAT through GWAS and GRS, casting further insight into this complicated matter.publishersversionpublishe
Aplicação do modelo de Scheffé no sistema de microextração líquido-líquido dispersiva de baixa densidade em amostra de soro de ruminantes para determinação de ácido linoleico / Application of the Scheffé model in the low-density dispersive liquid-liquid microextration system in a serum sample of ruminants for the determination of linoleic acid
Este trabalho tem como objetivo avaliar a triagem de uma técnica para a extração de lipídios e esterificação do ácido linoleico, contido no soro sanguíneo de ruminantes, aplicando o modelo polinomial de Scheffé na determinação das proporções de solventes utilizados na técnica de Microextração Líquido-Líquido Dispersiva de Baixa Densidade (LDS DLLME). Os solventes tolueno, metanol e solução salina aquosa de cloreto de magnésio 0,017% (m/v) foram selecionados para extração do ácido linoleico na técnica LDS DLLME. Após a extração, o ácido linoleico foi esterificado e analisado por cromatografia gasosa com detector de ionização em chamas (GC-FID). O modelo polinomial de Scheffé foi aplicado aos dados cromatográficos e o modelo cúbico completo (MCC) representou de maneira eficiente as informações do sistema químico. Os parâmetros e superfície de resposta obtidos indicaram que a melhor condição de extração de ácido linoleico do soro foi: 20,50 % (v/v) de tolueno, 39,75% (v/v) de metanol e 39,75 % (v/v) de solução salina aquosa de MgCl2 0,017 % (m/v).
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