767 research outputs found
Diversity of porcine rotavirus genotypes in São Paulo State, Brazil
Rotavírus é uma das causas mais comuns de diarréia tanto em humanos quanto em diferentes espécies animais. Foi conduzido um estudo transversal a partir de 144 amostras fecais diarréicas colhidas de leitões, provenientes de 16 criações comerciais distribuídas por 10 municípios do Estado de São Paulo, Brasil, com o objetivo de se detectar a ocorrência de rotavírus e realizar sua caracterização molecular quanto seus genotipos G e P. Um total de 43 amostras (29,86%) foram positivas para rotavírus por Eletroforese em Gel de Poliacrilamida (PAGE) e ELISA, num esquema de triagem em paralelo. A caracterização mediante reações do tipo nested-multiplex RT-PCR demonstrou que, isoladamente, o genotipo P[6] foi o mais frequente, detectado em 25,58% das amostras, seguido pelo P[1] (11,63%) e P[7] (9,3%). Infecções concomitantes de genotipos P[6]+P[7] (9,3%), P[1]+P[6] (4,65%), P[1]+P[6]+P[7] (2,33%) foram também observadas. Analogamente, o genotipo G[5] foi detectado em 30,23% das amostras, seguido pelo G[10] (20,93%) e G[6] (4,65%) e G[5]+G[10] (18,6%). O genotipo G[5]P[6] foi o mais frequente (11,63%), porém outras combinações e amostras não tipificáveis também foram observadas. Considerando-se a diversidade de rotavírus suínos encontrada na população estudada, medidas profiláticas específicas devem levar em conta, para sua efetividade, o grau de proteção cruzada entre os genotipos presentes nas formulações vacinais e aqueles que realmente são circulantes numa região.Rotavirus is one the most common causes of diarrhea both in humans and different animal species. It was carried out a transversal study with 144 diarrheic fecal samples of piglets, from 16 commercial swine-producing units distributed among 10 municipalities of São Paulo State, Brazil, aiming at the detection of rotavirus occurrence and its molecular characterization according to G and P genotypes. A total of 43 samples (29.86%) were positive for rotavirus by Polyacrylamide Gel Electrophoresis (PAGE) and ELISA, in a parallel screening scheme. The nested-multiplex RT-PCR characterization revealed that, separately, the P[6] genotype was the most frequent, detected in 25.58% of the samples, followed by P[1] (11.63%) and P[7] (9.3%). Concomitant infection of the genotypes P[6]+P[7] (9.3%), P[1]+P[6] (4.65%), P[1]+P[6]+P[7] (2.33%) were also found. Similarly, the G[5] genotype was detected on 30.23% of the samples, followed by G[10] (20.93%), G[6] (4.65%) and G[5]+G[10] (18.6%). The genotype G[5]P[6] was the most frequent (11.63%), but other combinations and untypeable samples were also observed. Considering the diversity porcine rotavirus found in the surveyed population, specific prophylactic measures should take in charge, for its effectiveness, the cross-protection degree between the genotypes present on vaccine formulations and those that really circulates on a region.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP
Entropic Upper Bound on Gravitational Binding Energy
We prove that the gravitational binding energy {\Omega} of a self gravitating
system described by a mass density distribution {\rho}(x) admits an upper bound
B[{\rho}(x)] given by a simple function of an appropriate, non-additive
Tsallis' power-law entropic functional Sq evaluated on the density {\rho}. The
density distributions that saturate the entropic bound have the form of
isotropic q-Gaussian distributions. These maximizer distributions correspond to
the Plummer density profile, well known in astrophysics. A heuristic scaling
argument is advanced suggesting that the entropic bound B[{\rho}(x)] is unique,
in the sense that it is unlikely that exhaustive entropic upper bounds not
based on the alluded Sq entropic measure exit. The present findings provide a
new link between the physics of self gravitating systems, on the one hand, and
the statistical formalism associated with non-additive, power-law entropic
measures, on the other hand
Enhancement of a solar photo-Fenton reaction by using ferrioxalate complexes for the treatment of a synthetic cotton-textile dyeing wastewater
Biological, photo-Fenton (PF) and photo-Fenton mediated by ferrioxalate complexes (PF/Ferrioxalate) processes were examined for the degradation of a synthetic cotton-textile dyeing wastewater. Aerobic biological treatment had a negligible effect on discolouration whereas total organic content decreased mainly due to the biodegradation of acetic acid initially present in the wastewater. PF process yielded a fast and pronounced dissolved organic carbon concentration decay, mostly associated to the abrupt precipitation of Fe(III)-organic complexes. The addition of oxalic acid limited iron precipitation, allowing mineralization of most organic contaminants. The influence of the different dyes and main dyeing auxiliary constituents of the synthetic textile wastewater on the PF and the PF/Ferrioxalate efficiency was systematically analysed. The suitability of combining PF/Ferrioxalate with conventional biological processes as a pre and/or post treatment was evaluated.This study highlights the potential of PF/Ferrioxalate reaction to mineralize the synthetic cotton-textile wastewater under appropriate experimental conditions, the best being: [Fe3+]=40mgL-1, iron/oxalate molar ratio=1:3, pH=4.0 and [H2O2]=50-100 (1.5-2.9)mgL-1 (mmolL-1). At these conditions, the PF/Ferrioxalate treatment was carried out under natural sunlight in a pilot plant equipped with compound parabolic collectors.Fil: Doumic, Lucila Inés. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; Argentina. Universidad de Porto; Portugal. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Industrias; ArgentinaFil: Soares, Petrick A.. Universidad de Porto; PortugalFil: Ayude, María Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; ArgentinaFil: Cassanello Fernandez, Miryam Celeste. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Industrias; ArgentinaFil: Boaventura, Rui A.R.. Universidad de Porto; PortugalFil: Vilar, Vítor J.P.. Universidad de Porto; Portuga
Coronavirus Disease 2019 and Human Reproduction: A Changing Perspective
Since the outbreak of severe acute respiratory coronavirus 2 (SARS-CoV-2), the coronavirus disease 2019 has had a wide range of effects on human health. This paper summarizes the data related to the effects of the SARS-CoV-2 infection on human reproduction.
Both the male and female reproductive tract express high levels of receptors and proteins needed for viral cell entry. There is presently no evidence that gametes are affected by the infection. Male fertility may be temporarily reduced due to inflammatory responses following infection. The endometrium is highly susceptible to SARS-CoV-2 cell entry; however, it remains unclear whether this could alter receptivity and embryo implantation. Menstrual cycle changes were reported in women who experienced severe infection; however, they tended to be reversible. For couples undergoing assisted reproduction treatment, the pandemic led to a significant psychological burden, with changes in lifestyle that could directly affect the success of the treatment. Human reproduction societies recommend screening all patients prior to cycle initiation and avoiding treatment of women with severe comorbidities until the pandemic is under control. Finally, for pregnant women, it is expected that the infection is more severe in women in the third trimester and in those with comorbidities. Those who are symptomatic for SARS-CoV-2 are more likely to have increased rates of prematurity and intrapartum fetal distress than those who are asymptomatic. Vertical transmission cannot be completely ruled out, but neonatal infection rates are low. Vaccination appears to be safe and is indicated for use in pregnant and lactating women because the benefits outweigh the risks
A dual-target herbicidal inhibitor of lysine biosynthesis
Herbicides with novel modes of action are urgently needed to safeguard global agricultural industries against the damaging effects of herbicide-resistant weeds. We recently developed the first herbicidal inhibitors of lysine biosynthesis, which provided proof-of- concept for a promising novel herbicide target. In this study, we expanded upon our understanding of the mode of action of herbicidal lysine biosynthesis inhibitors. We previously postulated that these inhibitors may act as proherbicides. Here, we show this is not the case. We report an additional mode of action of these inhibitors, through their inhibition of a second lysine biosynthesis enzyme, and investigate the molecular determinants of inhibition. Furthermore, we extend our herbicidal activity analyses to include a weed species of global significance.Emily RR Mackie, Andrew S Barrow, Rebecca M Christoff, Belinda M Abbott, Anthony R Gendall, Tatiana P Soares da Cost
Trojan-like internalization of anatase titanium dioxide nanoparticles by human osteoblast cells
Dentistry and orthopedics are undergoing a revolution in order to provide more reliable, comfortable and long-lasting implants to patients. Titanium (Ti) and titanium alloys have been used in dental implants and total hip arthroplasty due to their excellent biocompatibility. However, Ti-based implants in human body suffer surface degradation (corrosion and wear) resulting in the release of metallic ions and solid wear debris (mainly titanium dioxide) leading to peri-implant inflammatory reactions. Unfortunately, our current understanding of the biological interactions with titanium dioxide nanoparticles is still very limited. Taking this into consideration, this study focuses on the internalization of titanium dioxide nanoparticles on primary bone cells, exploring the events occurring at the nano-bio interface. For the first time, we report the selective binding of calcium (Ca), phosphorous (P) and proteins from cell culture medium to anatase nanoparticles that are extremely important for nanoparticle internalization and bone cells survival. In the intricate biological environment, anatase nanoparticles form bio-complexes (mixture of proteins and ions) which act as a kind of ‘Trojan-horse’ internalization by cells. Furthermore, anatase nanoparticles-induced modifications on cell behavior (viability and internalization) could be understand in detail. The results presented in this report can inspire new strategies for the use of titanium dioxide nanoparticles in several regeneration therapies
Transfer learning for galaxy morphology from one survey to another
© 2018 The Author(s). Published by Oxford University Press on behalf of the Royal Astronomical Society.Deep Learning (DL) algorithms for morphological classification of galaxies have proven very successful, mimicking (or even improving) visual classifications. However, these algorithms rely on large training samples of labelled galaxies (typically thousands of them). A key question for using DL classifications in future Big Data surveys is how much of the knowledge acquired from an existing survey can be exported to a new dataset, i.e. if the features learned by the machines are meaningful for different data. We test the performance of DL models, trained with Sloan Digital Sky Survey (SDSS) data, on Dark Energy survey (DES) using images for a sample of 5000 galaxies with a similar redshift distribution to SDSS. Applying the models directly to DES data provides a reasonable global accuracy ( 90%), but small completeness and purity values. A fast domain adaptation step, consisting in a further training with a small DES sample of galaxies (500-300), is enough for obtaining an accuracy > 95% and a significant improvement in the completeness and purity values. This demonstrates that, once trained with a particular dataset, machines can quickly adapt to new instrument characteristics (e.g., PSF, seeing, depth), reducing by almost one order of magnitude the necessary training sample for morphological classification. Redshift evolution effects or significant depth differences are not taken into account in this study.Peer reviewedFinal Accepted Versio
Adsorption of Cd, Cu, Ni and Zn in tropical soils under competitive and non-competitive systems
The adsorption of heavy metals in soils affects their behavior in the environment and their bioavailability to plants. The knowledge of the adsorption mechanisms in competitive systems allows a more realistic evaluation of the metals' behavior in the soil than the single metal adsorption. The objectives of this study were (i) to evaluate Cd, Cu, Ni, and Zn adsorption in 14 surface samples (0-0.2 m) of representative soils of the Brazilian humid-tropical region, in competitive and non-competitive systems, and (ii) to establish metal affinity sequences for each soil, based in the maximum adsorption capacity (MAC) estimated by the Langmuir model. The Rhodic Eutrudox, the Kandiudalf Eutrudox, the Arenic Hapludalf, the Arenic Hapludult and the Typic Argiudoll had the highest metals' adsorption capacity, whereas the Typic Quartzipsamment and the sandy-textured Arenic Hapludult had the lowest values. In general, the MAC values for metals were lower in the competitive than in the non-competitive system. In the non-competitive system, the most common affinity sequence was Cu > Zn > Ni > Cd, whereas the most common sequence was Cu > Cd > Zn > Ni in the competitive system. In general, the Langmuir model fitted well the adsorption data of metals on the studied soils.A adsorção de metais pesados em solos afeta seu comportamento e biodisponibilidade às plantas. O conhecimento dos mecanismos de adsorção em sistemas competitivos permite uma avaliação mais realista do comportamento dos metais no solo do que estudos com adsorção de cada metal, isoladamente. Os objetivos desse trabalho foram: (i) avaliar a adsorção de Cd, Cu, Ni e Zn em amostras superficiais (0-0,2 m) de 14 solos representativos da região tropical úmida, em sistema competitivo e não-competitivo, e (ii) estabelecer sequências de afinidade metálica para cada solo, com base nos valores de capacidade máxima de adsorção (CMA) dos metais estimados por meio do modelo de Langmuir. O Rhodic Eutrudox, o Kandiudalfic Eutrudox, o Arenic Hapludalf (Alf2), o Arenic Hapludult (Ult2) e o Typic Argiudoll apresentaram elevadas capacidades de adsorção dos metais, ocorrendo o inverso para o Typic Quartzipsamment e para o Arenic Hapludult textura arenosa. No geral, a CMA dos metais aos solos foi menor no sistema competitivo. A sequência de afinidade mais comumente encontrada no sistema não-competitivo foi Cu > Zn > Ni > Cd. No sistema competitivo, a sequência foi Cu > Cd > Zn > Ni. Em geral, o modelo de Langmuir simulou de maneira satisfatória a adsorção dos metais nas amostras de solo
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