190 research outputs found
Luz através de coberturas coloridas transparentes sobre Corynespora cassiicola causador da mancha-alvo no tomateiro
Luz através de coberturas coloridas transparentes sobre Corynespora cassiicola causador da mancha-alvo no tomateiro </htm
Design and validation of an innovative 3D printer containing a co-rotating twin screw extrusion unit
This paper presents the design and validation of an innovative 3D printer containing a co-rotating twin screw extrusion unit (Co-TSE). Single screw print heads were developed in the mid-2000s as an alternative to filament-based 3D printers, but they have limited process flexibility and mixing capacity. The new design accepts material in powder or micro-pellet form, and its dispersive and distributive mixing capacity can be fine tuned by setting output and screw rotation speed independently. The design combines a miniaturized modular Co-TSE operated under starve-fed conditions with a benchtop Cartesian platform. Numerical calculations were performed to ascertain whether the appropriate thermomechanical environment for polymer processing could be created by the proposed design. A prototype was built and extrusion tests were performed under different operating conditions, using polypropylene and a 90/10 wt% polypropylene/polystyrene blend. Two screw configurations were used, with and without kneading discs, to assess the response of the extrusion unit in terms of flow characteristics and mixing performance. The restriction to flow created by the mixing elements determines the starting melt position, and the average residence times, while their shearing and extensional action enhances homogenization effectiveness. The screw configuration and rotation speed do not affect the output, which depends only on the feed rate. Preliminary deposition tests were conducted to determine the feasible printing parameters. A standard tensile test specimen, a square scaffold and a multicolored rectangular box were successfully printed, validating the innovative design. The mechanical properties of printed test specimens were within the expected values.This work was supported by the National Council for Scientific and
Technological Development (CNPq), grants 2016-4/442109 and
142348/2018-0, and by the Coordination for the Improvement of
Higher Education Personnel (CAPES), finance code 001
Sclerosing mesenteritis as an unusual cause of fever of unknown origin: a case report and review
The Aspergillus fumigatus transcription factor RglT is important for gliotoxin biosynthesis and self-protection, and virulence
This is the final version (corrected proof). The final published version is available from Public Library of Science via the DOI in this recordData Availability: Short reads were submitted to the NCBI’s Sequence Read Archive under accession number SRP154617 (https://www.ncbi.nlm.nih.gov/sra/?term=SRP154617). The ChIPseq data are available from NCBI SRA (sequence read archive) database under accession number PRJNA574873 (https://www.ncbi.nlm.nih.gov/Traces/study/?acc=PRJNA574873&o=acc_s%3Aa).Aspergillus fumigatus is an opportunistic fungal pathogen that secretes an array of immune-modulatory molecules, including secondary metabolites (SMs), which contribute to enhancing fungal fitness and growth within the mammalian host. Gliotoxin (GT) is a SM that interferes with the function and recruitment of innate immune cells, which are essential for eliminating A. fumigatus during invasive infections. We identified a C6 Zn cluster-type transcription factor (TF), subsequently named RglT, important for A. fumigatus oxidative stress resistance, GT biosynthesis and self-protection. RglT regulates the expression of several gli genes of the GT biosynthetic gene cluster, including the oxidoreductase-encoding gene gliT, by directly binding to their respective promoter regions. Subsequently, RglT was shown to be important for virulence in a chemotherapeutic murine model of invasive pulmonary aspergillosis (IPA). Homologues of RglT and GliT are present in eurotiomycete and sordariomycete fungi, including the non-GT-producing fungus A. nidulans, where a conservation of function was described. Phylogenetically informed model testing led to an evolutionary scenario in which the GliT-based resistance mechanism is ancestral and RglT-mediated regulation of GliT occurred subsequently. In conclusion, this work describes the function of a previously uncharacterised TF in oxidative stress resistance, GT biosynthesis and self-protection in both GT-producing and non-producing Aspergillus species.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESPConselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior – Brasil (CAPES)Wellcome TrustUniversity of MacauNational Science Foundation (NSF)Vanderbilt UniversityHoward Hughes Medical Institut
SARS-CoV-2 antibody dynamics in blood donors and COVID-19 epidemiology in eight Brazilian state capitals: A serial cross-sectional study
BACKGROUND: The COVID-19 situation in Brazil is complex due to large differences in the shape and size of regional epidemics. Understanding these patterns is crucial to understand future outbreaks of SARS-CoV-2 or other respiratory pathogens in the country. METHODS: We tested 97,950 blood donation samples for IgG antibodies from March 2020 to March 2021 in 8 of Brazil's most populous cities. Residential postal codes were used to obtain representative samples. Weekly age- and sex-specific seroprevalence were estimated by correcting the crude seroprevalence by test sensitivity, specificity, and antibody waning. RESULTS: The inferred attack rate of SARS-CoV-2 in December 2020, before the Gamma variant of concern (VOC) was dominant, ranged from 19.3% (95% credible interval [CrI] 17.5-21.2%) in Curitiba to 75.0% (95% CrI 70.8-80.3%) in Manaus. Seroprevalence was consistently smaller in women and donors older than 55 years. The age-specific infection fatality rate (IFR) differed between cities and consistently increased with age. The infection hospitalisation rate increased significantly during the Gamma-dominated second wave in Manaus, suggesting increased morbidity of the Gamma VOC compared to previous variants circulating in Manaus. The higher disease penetrance associated with the health system's collapse increased the overall IFR by a minimum factor of 2.91 (95% CrI 2.43-3.53). CONCLUSIONS: These results highlight the utility of blood donor serosurveillance to track epidemic maturity and demonstrate demographic and spatial heterogeneity in SARS-CoV-2 spread. FUNDING: This work was supported by Itaú Unibanco 'Todos pela Saude' program; FAPESP (grants 18/14389-0, 2019/21585-0); Wellcome Trust and Royal Society Sir Henry Dale Fellowship 204311/Z/16/Z; the Gates Foundation (INV- 034540 and INV-034652); REDS-IV-P (grant HHSN268201100007I); the UK Medical Research Council (MR/S0195/1, MR/V038109/1); CAPES; CNPq (304714/2018-6); Fundação Faculdade de Medicina; Programa Inova Fiocruz-CE/Funcap - Edital 01/2020 Number: FIO-0167-00065.01.00/20 SPU N°06531047/2020; JBS - Fazer o bem faz bem
The sub-basin springs of Poxim river, state of Sergipe: the degradation to restoration
Estudos ambientais em bacias hidrográficas são fundamentais para o entendimento do uso dos recursos naturais e dos problemas relacionados à ocupação do espaço. Em Sergipe, há necessidade de se obter informações para fins de planejamento e gestão futura de suas bacias hidrográficas, uma vez que gradualmente observa-se uma redução do volume produzido nos cursos d'água e da qualidade de suas águas, que são imprescindíveis para o abastecimento humano, a utilização na agricultura e na indústria. Devido ao acelerado processo de supressão da vegetação na sub-bacia hidrográfica do rio Poxim, formada pelos rios Poxim-mirim, Poxim-açu, e Pitanga e seus pequenos tributários, foi realizado um diagnóstico para se verificar o estado de conservação das suas principais nascentes, a situação quanto ao fluxo de água, as formas de uso e ocupação do solo no entorno destas e os tipos fisionômicos de vegetação remanescentes. As informações obtidas serão úteis para a realização de projetos de restauração ambiental, a promoção de melhorias no ambiente e nas comunidades rurais e resgate da diversidade da flora e fauna nestas áreas. Observou-se que as 20 principais nascentes dos rios e tributários que compõem a sub-bacia hidrográfica do rio Poxim, apresentam alterações decorrentes da acelerada antropização (90%), a maioria delas (65%) com elevada degradação (sem raio mínimo de 50m de vegetação) e ocupadas por agricultura (50%) e pastagens (35%). Somente duas nascentes encontram-se preservadas. Quanto à composição florística, as espécies identificadas (43) podem ser utilizadas em projetos futuros para restauração das nascentes e dos cursos d'água nesta sub-bacia hidrográfica. _________________________________________________________________________________________ ABSTRACT: Environmental studies on river basins are fundamental to understanding the natural resources use and the problems related to the space occupation. In Sergipe, it is necessary to obtain information for planning purposes and future management of their watersheds, once the watercourses volume and its quality are reducing gradually, which are essential for human supply and use in agriculture and industry. Due to the accelerated removal of vegetation in the river Poxim sub-basin, formed by the Poxim-Mirim, Poxim-Açu, Pitanga rivers, and its small tributaries, a diagnosis was carried out to verify the conservation status of their main sources, the situation on the water flow, the different uses, and land use around these sources and the remaining vegetation physiognomic types. The information is useful for carrying out environmental restoration projects, promoting improvements in the environment and in the rural communities and for the flora and fauna diversity rescue in these areas. It was observed that the 20 rivers sources top and tributaries that compose the river Poxim sub-basin showed changes from accelerated human anthropization (90%), most (65%) with high degradation (no vegetation in the minimum radius of 50 m), being occupied by agriculture (50%) and pastures (35%). Only two sources were preserved. The floristic composition, the identified species (43) can be used in future projects for sources and watercourses restoration in this sub-basin
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