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This study evaluated the genetic diversity and antimicrobial susceptibility of Staphylococcus aureus isolates from dairy cows in Minas Gerais, Brazil. Thirty-seven isolates from five municipalities (8 herds) were genotyped using multi-locus sequence typing (MLST) and susceptibility to 12 antimicrobial agents was tested using the disk diffusion method. High resistance rates for penicillin [75.68% (28/37)], ampicillin [70.27% (26/37)], and tetracycline [70.27% (26/37)] were detected. Multidrug resistance was observed in seven [18.92% (7/37)] isolates, and two were suggestive of Methicillin-resistant Staphylococcus aureus (MRSA). Among the 37 isolates, 33 novel sequence types (ST) and two known STs (ST126 and ST746) were identified in MLST. The clonal complexes more frequently observed were: CC97 [78.38%; (29/37)], CC1 [8.11%; (3/37)] and CC5 [5.40%; (2/37)]. Minimum?spanning tree (MST) analysis according to data from municipalities, herds, and resistance patterns for all isolates did not show any clustering pattern. However, the MST comparing all Brazilian S. aureus isolates deposited in the PubMLST database and from this study depicted an association between the genotype and strain origin (clinical sample). Isolates from this study that belong to CC97 were close to database isolates from milk and dairy products, while those that belong to CC1 and CC5 were close to database isolates from human sources and the environment of dairy farms or industries. In conclusion, our results showed a high rate of resistance to penicillins and tetracyclines and great genetic diversity among the S. aureus isolates from bovine mastitis genotyped in the present study. RESUMO - Este estudo teve como objetivo avaliar a diversidade genética e a suscetibilidade a antimicrobianos de cepas de Staphylococcus aureus isoladas de vacas leiteiras em Minas Gerais, Brasil. Trinta e sete cepas provenientes de cinco municípios (oito rebanhos) foram genotipadas usando a técnica multi-locus sequence typing (MLST) e a suscetibilidade a 12 antimicrobianos foi avaliada pelo método de difusão em disco. Foram detectadas altas taxas de resistência para penicilina [75,68% (28/37)], ampicilina [70,27% (26/37)] e tetraciclina [70,27% (26/37)] entre os isolados. A multirresistência foi observada em sete [18,92% (7/37)] isolados e dois foram classificados como sugestivos de Staphylococcus aureus resistente à meticilina (MRSA). Entre os 37 isolados, 33 novos sequence types (ST) e dois STs conhecidos (ST126 e ST746) foram identificados pelo MLST. Os complexos clonais mais frequentemente observados foram: CC97 [78,38%; (29/37)], CC1 [8,11%; (3/37)] e CC5 [5,40%; (2/37)]. Foi construída uma minimum?spanning tree (MSTs) com todos isolados estudados e esta não mostrou padrão de agrupamento quando comparada com dados epidemiológicos como municípios e rebanho, do qual foi isolado, e perfis de resistência a antimicrobianos. Uma segunda MST foi construída comparando os isolados deste estudo e todas as cepas de S. aureus depositadas no banco de dados PubMLST provenientes do Brasil, que mostrou associação entre o genótipo, STs e a origem da cepa. Foi possível observar entre os isolados do estudo que, aqueles que pertenciam ao CC97, eram geneticamente mais próximos das cepas depositadas no PubMLST isoladas de leite e de produtos lácteos, enquanto aqueles que pertenciam aos CC1 e CC5 estavam mais próximos a cepas isoladas de humanos ou do ambiente de fazendas e indústrias de laticínios. Em conclusão, nossos resultados mostraram um alto índice de resistência às penicilinas e tetraciclinas e grande diversidade genética entre as cepas de S. aureus isoladas de casos de mastite bovina. Made available in DSpace on 2022-07-21T11:19:21Z (GMT). No. of bitstreams: 1 Genetic-diversity-and-antimicrobial-susceptibility-of-Staphylococcus-aureus.pdf: 1189969 bytes, checksum: 7d02b2551a4c2c2287f83cc00c8d4562 (MD5) Previous issue date: 2023

This study aimed to describe the epidemiological indexes of mastitis, milk quality and udder hygiene in the Compost Barn system, as well as to search for associations between isolated pathogens from milk with compost characteristics. Three dairy herds participated in the study, and the samples were collected during different periods on each farm. Individual milk samples were collected in duplicate for SCC analysis and microbiological culture. Environmental pathogens caused most cases of clinical mastitis on farm 2, and contagious pathogens caused the most cases on farm 1. Bed moisture was not associated with the incidence of environmental pathogens. Most of the animals remained in good udder hygiene during the study. Poor udder hygiene contributed to the increased incidence of environmental pathogens in one of the farms. A higher number of animals with a hygiene score of ≥ 2 were observed during the warmer and rainfall periods. There was no association between hygiene scores and somatic cell counts. The results suggest that pathogens isolated from milk in animals confined in Compost Barn under tropical climate are like other confinement systems adopted elsewhere. The year period influenced the udder hygiene score, reinforcing the importance of bed management throughout the year. RESUMO O objetivo deste estudo foi descrever os índices epidemiológicos da mastite, da qualidade do leite e da higiene do úbere em animais confinados no sistema Compost Barn, bem como buscar associações entre patógenos isolados do leite e características do composto. Três rebanhos leiteiros participaram do estudo e as amostras foram coletadas em diferentes períodos em cada fazenda. Amostras individuais de leite foram coletadas em duplicata para análise de CCS e cultura microbiológica. Patógenos ambientais causaram a maioria dos casos de mastite clínica na fazenda 2, e na fazenda 1 a maioria dos casos foi em decorrência de patógenos contagiosos. Amostras de material da cama foram coletadas em duas fazendas para análise da densidade bacteriana e da umidade. A umidade da cama permaneceu dentro da faixa de controle durante o estudo e não foi associada à incidência de patógenos ambientais. A maioria dos animais permaneceu com boa higiene de úbere durante o estudo. A falta de higiene do úbere contribuiu para o aumento da incidência de patógenos ambientais em uma das fazendas. Durante o período mais quente e mais chuvoso, um número maior de animais com escore de sujidade ≥ 2 foi observado em todos os rebanhos. Não houve associação entre escore de sujidade e contagem de células somáticas em qualquer uma das três fazendas. Os resultados indicam que o perfil de patógenos isolados do leite em animais confinados em Compost Barn sob clima tropical é semelhante a outros sistemas de confinamento adotados em outros lugares. O período do ano influenciou o escore de higiene do úbere, o que reforça a importância do manejo da cama ao longo do ano.

In this article, we used the numerical self-consistent field method of Scheutjens–Fleer to study the micellization of hybrid molecules consisting of one polylysine dendron with charged end groups and several linear hydrophobic tails attached to its root. The main attention was paid to spherical micelles and the determination of the range of parameters at which they can appear. A relationship has been established between the size and internal structure of the resulting spherical micelles and the length and number of hydrophobic tails, as well as the number of dendron generations. It is shown that the splitting of the same number of hydrophobic monomers from one long tail into several short tails leads to a decrease in the aggregation number and, accordingly, the number of terminal charges in micelles. At the same time, it was shown that the surface area per dendron does not depend on the number of hydrophobic monomers or tails in the hybrid molecule. The relationship between the structure of hybrid molecules and the electrostatic properties of the resulting micelles has also been studied. It is found that the charge distribution in the corona depends on the number of dendron generations G in the hybrid molecule. For a small number of generations (up to (Formula presented.)), a standard double electric layer is observed. For a larger number of generations ((Formula presented.)), the charges of dendrons in the corona are divided into two populations: in the first population, the charges are in the spherical layer near the boundary between the micelle core and shell, and in the second population, the charges are near the periphery of the spherical shell. As a result, a part of the counterions is localized in the wide region between them. These results are of potential interest for the use of spherical dendromicelles as nanocontainers for drug delivery.

The design of nanoassemblies can be conveniently achieved by tuning the strength of the hydrophobic interactions of block copolymers in selective solvents. These block copolymer micelles form supramolecular aggregates, which have attracted great attention in the area of drug delivery and imaging in biomedicine due to their easy-to-tune properties and straightforward large-scale production. In the present work, we have investigated the micellization process of linear–dendritic block copolymers in order to elucidate the effect of branching on the micellar properties. We focus on block copolymers formed by linear hydrophobic blocks attached to either dendritic neutral or charged hydrophilic blocks. We have implemented a simple protocol for determining the equilibrium micellar size, which permits the study of linear–dendritic block copolymers in a wide range of block morphologies in an efficient and parallelizable manner. We have explored the impact of different topological and charge properties of the hydrophilic blocks on the equilibrium micellar properties and compared them to predictions from self-consistent field theory and scaling theory. We have found that, at higher degrees of branching in the corona and for short polymer chains, excluded volume interactions strongly influence the micellar aggregation as well as their effective charge., DFG-RBS Russia Cooperation, RFBR

Despite recent progress in terms of cheap computing power, the application of physically-based distributed (PBD) hydrological codes still remains limited, particularly, because some commercial-license codes are expensive, even under academic terms. Thus, there is a need for testing the performance of free-license PBD codes simulating complex catchments, so that cheap and reliable mechanistic modelling alternatives might be identified. The hydrology of a geologically complex catchment (586 km2) was modelled using the free-license PBD code SHETRAN. The SHETRAN evaluation took place by comparing its predictions with (i) discharge and piezometric time series observed at different locations within the catchment, some of which were not taken into account during model calibration (i.e., multi-site test); and (ii) predictions from a comparable commercial-license code, MIKE SHE. In general, the discharge and piezometric predictions of both codes were comparable, which encourages the use of the free-license SHETRAN code for the distributed modelling of geologically complex systems.

Science needs everyone and everything; therefore, art must be used for its understanding. As the popularity of social media grows, absurd theories have been gaining consensus and, even worse, becoming factual truths without any criticism for many. Thus, aiming to find solutions for a better understanding of our scientific theories, the project “The earth is flat! And, now what?” was created. This project uses performing art as the main communicator to spread science. The first step consisted of calling a meeting to promote integration among the project participants and professionals from different areas of expertise such as geophysicists, art educators, artists, astronomers, and clowns. The meeting was also an occasion for planning the show. The second step consisted of developing the dramaturgy along with the creative process, which involved discussions on scenes and lessons about the theme to be presented, and the third step was the performance. The bibliographical review, the equivalent of the “table's work” for artists, was not based on indexed journals, but rather on social networks and classes for understanding the shape of the Earth. The show impacts the audience in a fun way, offering the opportunity for the general population to experience science in a new way.

Adversarial attacks perturb images such that a deep neural network produces incorrect classification results. A promising approach to defend against adversarial attacks on natural multi-object scenes is to impose a context-consistency check, wherein, if the detected objects are not consistent with an appropriately defined context, then an attack is suspected. Stronger attacks are needed to fool such context-aware detectors. We present the first approach for generating context-consistent adversarial attacks that can evade the context-consistency check of black-box object detectors operating on complex, natural scenes. Unlike many black-box attacks that perform repeated attempts and open themselves to detection, we assume a "zero-query" setting, where the attacker has no knowledge of the classification decisions of the victim system. First, we derive multiple attack plans that assign incorrect labels to victim objects in a context-consistent manner. Then we design and use a novel data structure that we call the perturbation success probability matrix, which enables us to filter the attack plans and choose the one most likely to succeed. This final attack plan is implemented using a perturbation-bounded adversarial attack algorithm. We compare our zero-query attack against a few-query scheme that repeatedly checks if the victim system is fooled. We also compare against state-of-the-art context-agnostic attacks. Against a context-aware defense, the fooling rate of our zero-query approach is significantly higher than context-agnostic approaches and higher than that achievable with up to three rounds of the few-query scheme., Comment: CVPR 2022 Accepted

Stock Markets are one of today ́s greatest asset for investors, nonetheless, Political Events can be one of today ́s biggest challenge, as they add a crucial component: Uncertainty. This study aims to understand the impact of (Portuguese) Political Events on the Portuguese Stock Market. Specifically, it investigates the complex relations between these concepts, while analyzing how developments in each field both influence and are influenced by each other. To provide relevant conclusions, an extensive literature review regarding classical theories and past academic works was carried, as well as, considerations regarding a more recent approach to stock markets: Sentimental Analysis. Furthermore, a statistical analysis was performed using two different methodologies; Event Study and the Regression Analysis. The results obtained show that are significant influences and connections between Political Events and the Portuguese Stock Index (PSI-Geral): On this basis, conclusions were drawn such as Regional Elections impact positively the Index, on the other hand, European Elections have a negative impact. Another main conclusion is that Negative Political News have more weight that Positive Political News. This study intends to provide relevant information to market investors in the evaluation process for future investments. As Bolsas de Valores são um dos maiores trunfos atuais para os investidores, no entanto, os Eventos Políticos podem ser um dos maiores desafios atuais, uma vez que acrescentam uma componente crucial: Incerteza. Este estudo visa compreender o impacto dos Eventos Políticos (portugueses) na Bolsa de Valores Portuguesa. Especificamente, investiga as complexas relações entre estes conceitos, analisando ao mesmo tempo como os desenvolvimentos em cada campo influenciam e são influenciados um pelo outro. De modo a obter conclusões relevantes, foi feita uma extensa revisão bibliográfica sobre teorias clássicas e trabalhos académicos passados, bem como considerações sobre uma abordagem mais recente aos mercados bolsistas: Análise Sentimental. Além disso, foi realizada uma análise estatística utilizando duas metodologias diferentes: o Estudo de Eventos e a Análise de Regressão. Os resultados obtidos indicam que de facto, existem influências e ligações significativas entre Eventos Políticos e o Índice Geral para o mercado acionista Português (PSI-Geral): Nesta base, foram retiradas conclusões, tais como: o impacto positivo das Eleições Autárquicas no Índice e por outro lado, o impacto negativo das Eleições Europeias no Índice. Outra conclusão a mencionar, as Notícias Políticas Negativas têm mais peso que as Notícias Políticas Positivas. Este estudo pretende fornecer informações relevantes aos investidores do mercado no processo de avaliação para investimentos futuros.

The Fintech market has been growing at a fast pace, and the Iberia region is no exception. The trend towards digitization has been accelerated by the pandemic and has forced traditional financial players to adapt. The project firstly depicts the global market environment, assessing the evolution of the number of players, the size of the funding, and the M&A activity. Results indicate the industry has both growing liquidity and variety of innovative offers. Lastly, an analysis of the European regulation landscape shows regulatory authorities are conducting efforts to foster innovation, through the implementation of innovation hubs and regulatory sandboxes.

[EN] The impact of individual and combined pulsed electric field (PEF) and high power ultrasound (HPU) on the inactivation of different microorganisms in emulsions was investigated. The highest inactivation level using PEF was 2.6, 1.2 and 0.1 log-cycles for Escherichia coli, Aspergillus niger and Bacillus pumilus, respectively, achieved at the highest energy level and temperature (152.3-176.3 kJ/kg and 25 degrees C). HPU led to the highest reduction (5.4, 4.3 and 0.3 log-cycles for E. coli, A. niger and B. pumilus, respectively) after the longest treatment time studied (3 min). PEF (152.3-176.3 kJ/kg) followed by HPU (3 min) was found to be the most effective sequence, leading to synergistic effects (6.6 and 1.0 log-cycles for A. niger and B. pumilus, respectively), compared to the individual treatments. PEF-HPU is a promising hurdle technology with which to inactivate vegetative bacteria or fungal spores in emulsions. However, limited inactivation was achieved for bacterial spores., The authors acknowledge the financial support from Fresenius Kabi

RESUMO O estudo analisou a sistematização da Ginástica nas aulas de Educação Física, procurando refletir sobre a necessidade de existir uma sequência do ensino visando às aprendizagens dos estudantes. A investigação ocorreu a partir de uma pesquisa qualitativa, em que foram utilizados questionários, entrevistas e observações. Constatou-se que as dificuldades e problemáticas presentes no contexto escolar são diversas. Identificou-se, ainda, que mesmo diante da complexa realidade nas escolas, existe a preocupação com o ensino do conhecimento Ginástica de maneira sistematizada. Desta forma, tal preocupação tem contribuído com a formação dos estudantes das escolas investigadas, mediante as alternativas e ações criadas pelos professores para a sistematização da Ginástica. ABSTRACT The study analyzed the systematization of Gymnastics in Physical Education classes, seeking to reflect on the need for sequence of teaching aimed at students' learning. The investigation took place from a qualitative research, in which questionnaires, interviews and observations were used. It was found that the difficulties and problems present in the school context are diverse. It was also identified that despite the complex reality in schools, there is a concern with teaching Gymnastics knowledge in a systematic way. In this way, this concern has contributed to the training of students in the investigated schools, through the alternatives and actions created by teachers to systematize Gymnastics. RESUMEN El estudio analizó la sistematización de las clases de Gimnasia en Educación Física, buscando reflexionar sobre la necesidad de una secuencia de enseñanza. La investigación se realizó a partir de una investigación cualitativa, en la que se utilizaron cuestionarios, entrevistas y observaciones. Se encontró que las dificultades y los problemas presentes en el contexto escolar son diversos. También se identificó que, a pesar de la compleja realidad en las escuelas, existe la preocupación de enseñar el conocimiento de gimnasia de manera sistemática. De esta manera, esta preocupación ha contribuido a la formación de los estudiantes en las escuelas investigadas, a través de las alternativas y acciones creadas por los docentes para sistematizar la gimnasia.

Understanding and detecting diseases of amphibians has become vitally important in conservation and ecological studies and prevent and biosecurity a determinant priority in experimental farms, mainly when related with academic and research activities. Ranavirus belongs to the family Iridoviridae, and causes an emergent infectious disease that affects different species, especially fish, reptiles and amphibians, with a significant contribution to the decline of the population. In amphibian systems, Ranaviruses transmission can occur between vertebrate classes through direct contact, by scavenging or through virus particles persisting in the environment. Subclinical infected individuals may serve as reservoirs in the most susceptible anura species. Humans play a significant role in this emergent disease and biosecurity measures are determinant to prevent the introduction of these viruses, either in commercial or experimental farms. A Biosafety Plan is a fundamental tool in the Ranaviruses prevention and include educational and training programs, relevant to the mission of a Higher Education Institution.