Critical Evaluation of Possible Contamination by Toxic Metals in Powdered Milk During the Production Process

This study used an interdisciplinary approach to bring together some of the necessary and fundamental knowledge in the processing of powdered milk, mainly in relation to the materials used in the manufacture of equipment used in industrial processing. In order to clarify this issue, questions are presented on problems of corrosion, erosion and contamination by microorganisms that can generate or contribute to toxic metal leaching and consequently contaminate milk powder. In this work, we developed a method using atomic absorption spectroscopy with electro-thermal atomization to determine levels of cadmium, lead and nickel. To evaluate the possibility of contamination, we tested 15 samples of various brands of milk powder purchased in shops. Fortunately, the levels of these elements, in all samples, were lower than the maxima allowed under Brazilian law. However, this method of chemical analysis can be used as a tool of quality as the contamination that may occur during the production process

Bound states in the dynamics of a dipole in the presence of a conical defect

In this work we investigate the quantum dynamics of an electric dipole in a $(2+1)$-dimensional conical spacetime. For specific conditions, the Schr\"odinger equation is solved and bound states are found with the energy spectrum and eigenfunctions determined. We find that the bound states spectrum extends from minus infinity to zero with a point of accumulation at zero. This unphysical result is fixed when a finite radius for the defect is introduced.Comment: 4 page

Inovação, Concorrência e Crescimento Empresarial- Teoria e Política Aplicadas À Indústria de Fitoterápicos no Brasil

O estudo refere-se à análise das políticas de desenvolvimento produtivo no Brasil usando por base as teorias neochumpeterianas e evolucionárias. Para tal demonstra-se a importância da inovação, da concorrência e da regulação para a formulação de uma trajetória de crescimento empresarial para as indústrias nacionais, identificando estratégias inovativas que favoreçam esse crescimento bem como as possíveis trajetórias que esse crescimento pode adotar. Como exemplificação dos impactos da inovação, o estudo verifica a fitoterapia como possível setor industrial a ser beneficiado pelas políticas de inovação no Brasil e como o desenvolvimento do setor pode impulsionar o crescimento nacional. Inovação é o desenvolvimento de novos produtos, serviços, melhoramento de técnicas ou de métodos de produção existentes, da adaptação de tecnologias desenvolvidas bem sucedidas. A introdução da inovação aumenta a concorrência e consequentemente os lucros, levando ao crescimento das empresas. A fitoterapia tem potencial para ser o paradigma tecnológico que levará o Brasil a aproximar-se da fronteira tecnológica mundial e consequentemente viabilizar o desenvolvimento brasileiro, com aumento da renda e do emprego através do fortalecimento da indústria nacional.

CD4 T follicular cells and B cells

© 2023 Wiley-VCH GmbH.Regulatory and effector cell responses to Plasmodium vivax, the most common human malaria parasite outside Africa, remain understudied in naturally infected populations. Here, we describe peripheral CD4 + T- and B-cell populations during and shortly after an uncomplicated P. vivax infection in 38 continuously exposed adult Amazonians. Consistent with previous observations, we found an increased frequency in CD4 + CD45RA - CD25 + FoxP3 + T regulatory cells that express the inhibitory molecule CTLA-4 during the acute infection, with a sustained expansion of CD21 - CD27 - atypical memory cells within the CD19 + B-cell compartment. Both Th1- and Th2-type subsets of CXCR5 + ICOS hi PD-1 + circulating T follicular helper (cTfh) cells, which are thought to contribute to antibody production, were induced during P. vivax infection, with a positive correlation between overall cTfh cell frequency and IgG antibody titers to the P. vivax blood-stage antigen MSP1 19 . We identified significant changes in cell populations that had not been described in human malaria, such as an increased frequency of CTLA-4 + T follicular regulatory cells that antagonize Tfh cells, and a decreased frequency of circulating CD24 hi CD27 + B regulatory cells in response to acute infection. In conclusion, we disclose a complex immunoregulatory network that is critical to understand how naturally acquired immunity develops in P. vivax malaria.publishersversionepub_ahead_of_prin

Robótica'2001 - Festival Nacional de Robótica

O ROBÓTICA’2001 – Festival Nacional de Robótica visa promover desenvolvimentos técnicos e científicos na área da Robótica Móvel e áreas afins (electrónica, mecânica, programação, visão por computador, inteligência artificial, navegação, controlo, etc) através de um problema motivador, a ser resolvido por diferentes grupos de investigadores e estudantes. Procura-se ainda difundir a Ciência e a Tecnologia junto do público em geral e dos jovens em particular, nomeadamente motivando estes últimos para a aprendizagem experimental da Ciência. O objectivo principal dos participantes no evento deverá ser pois aprender e partilhar a sua aprendizagem com os colegas, tendo em vista a evolução da Robótica. Este evento consistiu em três actividades paralelas: uma competição de robótica móvel (em duas modalidades), um encontro científico e ainda várias demonstrações de outros robôs móveis e/ou autónomos

Mobile robot competitions: fostering advances in research, development and education in robotics

Mobile robot competitions are events well suited to experimentation, research and development in many areas concerned with science and technology, ranging from material science to artificial intelligence. Aware of this fact, and for several years now, some Portuguese Universities have been involving some of their Engineering and Computer Science students in such contests, namely those of international level. The performance has been improving both in terms of the results and prizes obtained and the increasingly elaborate technical solutions developed by the teams. The importance recognised in these events has led the authors to submit to the Portuguese Government a proposal for an annual Festival of this kind in Portugal. This paper points out the advances in research, technology and education, which result from this type of events

The Minor Envelope Glycoproteins GP2a and GP4 of Porcine Reproductive and Respiratory Syndrome Virus Interact with the Receptor CD163

Porcine reproductive and respiratory syndrome virus (PRRSV) contains the major glycoprotein, GP5, as well as three other minor glycoproteins, namely, GP2a, GP3, and GP4, on the virion envelope, all of which are required for generation of infectious virions. To study their interactions with each other and with the cellular receptor for PRRSV, we have cloned each of the viral glycoproteins and CD163 receptor in expression vectors and examined their expression and interaction with each other in transfected cells by coimmunoprecipitation (co-IP) assay using monospecific antibodies. Our results show that a strong interaction exists between the GP4 and GP5 proteins, although weak interactions among the other minor envelope glycoproteins and GP5 have been detected. Both GP2a and GP4 proteins were found to interact with all the other GPs, resulting in the formation of multiprotein complex. Our results further show that the GP2a and GP4 proteins also specifically interact with the CD163 molecule. The carboxy-terminal 223 residues of the CD163 molecule are not required for interactions with either the GP2a or the GP4 protein, although these residues are required for conferring susceptibility to PRRSV infection in BHK-21 cells. Overall, we conclude that the GP4 protein is critical for mediating interglycoprotein interactions and, along with GP2a, serves as the viral attachment protein that is responsible for mediating interactions with CD163 for virus entry into susceptible host cell

Preliminary Analysis of the Use of Construction Waste to Replace Conventional Aggregates in Concrete

This work aims to study the influence of using construction and demolition waste in the replacement of coarse and fine aggregate to produce recycled aggregate concrete (RAC). A moderate compressive strength concrete made with usual fine and coarse aggregate was used as a benchmark material. Compressive and split tensile tests were performed using 120 cylindrical concrete specimens with 150 mm diameter and 300 mm length. Four-point flexural tests in reinforced beams made with conventional concrete and RAC were performed. The results obtained showed that the use of recycled fine aggregates, in both percentages of substitution investigated-50% and 100%-did not generate any deleterious influence on the values of compressive strength and split tensile strength of the RACs produced. Tin fact, the mechanical strengths of RACs produced with recycled fine aggregate were equal or higher than those from the reference concrete. The same behavior was not observed, however, when the recycled coarse aggregate was used. For this case, decreases in concrete mechanical strengths were observed, especially in compressive strength, with values around 35% lower when compared to the reference concrete. Tensile mechanical tests results confirmed the excellent behavior of all RACs made with replacement of usual fine aggregates by recycled. Bending tests performed in reinforced RAC beams had as objective to evaluate the deformation profile of the beams. The obtained results showed that RAC beams with full replacement of usual fine aggregate by the recycled aggregates have presented little changes in the global behavior, an aspect that encourages its use