Amperometric Self-Referencing Ceramic Based Microelectrode Arrays for D-Serine Detection

D-serine is the major D-amino acid in the mammalian central nervous system. As the dominant co-agonist of the endogenous synaptic NMDA receptor, D-serine plays a role in synaptic plasticity, learning, and memory. Alterations in D-serine are linked to neuropsychiatric disorders including schizophrenia. Thus, it is of increasing interest to monitor the concentration of D-serine in vivo as a relevant player in dynamic neuron-glia network activity. Here we present a procedure for amperometric detection of D-serine with self-referencing ceramic-based microelectrode arrays (MEAs) coated with D-amino acid oxidase from the yeast Rhodotorula gracilis (RgDAAO). We demonstrate in vitro D-serine recordings with a mean sensitivity of 8.61 ± 0.83 pA/µM to D-serine, a limit of detection (LOD) of 0.17 ± 0.01 µM, and a selectivity ratio of 80:1 or greater for D-serine over ascorbic acid (mean ± SEM; n = 12) that can be used for freely moving studies

Molecular level understanding of supramolecular gels

Supramolecular gels are complex materials which have an expanding scope of industrial and biomedical applications, due to their unique viscoelastic properties, high biocompatibility and possibility of functionalisation. The hierarchical structure of molecular materials combines domains with drastically different degrees of ordering and molecular mobility. This makes their full characterisation a significant methodological and experimental challenge. The focus of this work was therefore the understanding of a variety of supramolecular semicrystalline gels in which very rigid solid components coexist with a dynamic and highly mobile solution phase. Using the examples of amino acid and urea-derivatives gelators, control of the self-assembly processes was successfully gained and tuning of the mechanical properties of the resulting materials by incorporating molecular structure modifications or introducing a variety of structurally diverse additives was achieved. Modification of the structure of the gel fibres was observed, which modulated the dynamic properties of the gel/solution interfaces and dictated the overall behaviour of the system, an aspect which is not commonly investigated in molecular gels. The resulting single and multi-component gels were used as model materials for the development of an NMR-based general strategy capable of probing the several hierarchical levels present. The multiphasic character of molecular gels required the combined use of solid, solution-state and HR-MAS NMR methods. This project has expanded the understanding of saturation transfer difference NMR experiments, with special focus in their applicability and limitations for the study of supramolecular soft systems. This approach was validated using complementary techniques, more specifically, rheology, microscopy, X-ray diffraction and computational methods. By combining molecular level understanding and measurements of the bulk properties, a methodology which can be applied to other soft materials used in pharmaceutical, biomedical and food science applications was developed. Moreover, this approach might have a generic impact in different fields of science and technology, enabling one to direct the recognition and host-guest properties of soft solids, which is essential for their targeted applications

A internacionalização de Business Schools e o fator cliente, no contexto da pandemia COVID-19

O conceito de internacionalização nem sempre teve um significado comum a todas as perspetivas e tem vindo a evoluir ao longo dos tempos, na medida em que transcende vários domínios. Foi, por isso, interessante iniciar este trabalho final de mestrado com uma descrição sucinta da evolução do termo em questão, ao longo dos anos, sobre a perspetiva de vários autores, afunilando para a esfera das business schools, de modo que se consiga perceber como é que este conceito era encarado pelas mesmas, de acordo com as perspetivas existentes. Para melhor perceber como é que as business schools responderam à pandemia da COVID-19, foi preponderante descrever o clima em que estas se encontravam, relativamente à conjunção das suas estratégias de internacionalização com a pandemia que se iniciou em 2020. O facto de haver uma pandemia não invalida estipular estratégias de internacionalização, tendo sido possível perceber alguns dos entraves que surgiram. Por último, o objetivo era compreender de que forma os clientes das business schools (os estudantes), encaravam a evolução desta qualidade das business schools, como fator de decisão da sua escolha de instituição para prosseguir os seus estudos, agregado à época pós-pandémica, como na época pré-pandémica. O método utilizado na presente tese é, na sua essência, qualitativo, tendo sido realizadas dez entrevistas a indivíduos que se encontravam atualmente numa business school, que estiveram numa business school e que ambicionavam integrar uma business school, de modo que se perceba as suas escolhas, face à situação em que se encontravam.The concept of internationalization has not always had a common meaning for all the existing perspectives and certainly, has evolved over time. It was, therefore, interesting to begin this final master's work with a succinct description of the evolution of the internationalization term over the years, from the perspective of several authors, narrowing down to the sphere of business schools, so that one can understand the concept, according to the existing perspectives. To better understand how business schools responded to the COVID-19 pandemic, it was important to describe the climate in which they found themselves, in relation to the combination of their internationalization strategies with the pandemic that began in 2020. The fact that there was a pandemic does not invalidate stipulating internationalization strategies, and it was possible to perceive some of the obstacles that arose. Finally, the objective was to understand how the customers of business schools (students) saw the evolution of the reaction of business schools, as a decision factor in their choice of institution to continue their studies, added to the post-pandemic period, never forgetting what motivated them in the pre-pandemic era. The method used in this thesis is, in essence, qualitative, with ten interviews being carried out with individuals who are currently in a business school, who were in a business school and other who wanted to join a business school, so that their choices can be understood, given each situation

Developing and validating a measure of the strength of the HRM system: Operationalizing the construct and relationships among its dimensions

The four studies in this article introduce a questionnaire to measure Strength of the HRM System (HRMSQ), a multidimensional construct, theoretically developed by Bowen and Ostroff (2004). Strength of the HRM System is a set of process characteristics that lead to effectiveness in conveying signals to employees that allow them to create a shared meaning of desired and appropriate work behaviours. Nine characteristics are suggested, grouped in three features: Distinctiveness, Consistency and Consensus. Study 1 developed and tested a questionnaire in a sample of workers from five different sectors. Study 2 cross-validated the measure in a sample of civil servants in a municipality. These two studies used performance appraisal as the reference HRM practice and led to a short version of the HRMSQ. Study 3 and Study 4 extend the HRMSQ to several common HRM practices. The HRMSQ is tested in two samples, of call center and several private and public organizations‟ workers (study 3). In study 4 the questionnaire is refined and tested with a sample from a hotel chain and finally cross-validated with two other samples, in the insurance and batteries sectors, leading to a longer version of the HRMSQ. Content analysis of several interviews with human resource managers and the Rasch model (1960, 1961, 1980), were used to define and select the indicators of the questionnaire. Convergent, discriminant and predictive validity of the measure are tested. The results of the four studies highlight the complexity of the relationships between the proposed characteristics and support the validity of a parsimonious measure of Strength of the HRM System.Research grant by Fundação para a Ciência e Tecnologi

Recognition and uses of Rhea Tarapacensis by residents in the catchment area of the San Guillermo Biosphere reserve (San Juan, Argentina)

Rhea tarapacensis es una especie amenazada que está ecológicamente extinta en parte de su distribución. Es una de las especies más usadas en medicina tradicional en los alrededores de la Reserva de Biosfera San Guillermo (San Juan, Argentina), quedando aún por evaluar el reconocimiento por parte de los pobladores, los nombres comunes que recibe y otros usos históricos y actuales. Este estudio se llevó a cabo en poblaciones cercanas a la reserva, donde se realizaron entrevistas semiestructuradas a 171 pobladores de ambos sexos mayores de 15 años, con diferentes actividades y niveles educativos. El 95% reconoció a Rhea tarapacensis y localmente es llamada Avestruz, Chure, Churi o Ñandú. Los colaboradores mencionaron un fuerte uso histórico de su carne y sus plumas, y un menor pero importante uso actual. Los hombres, los pobladores de entre 31–45 años de edad y los habitantes de Tudcum fueron los que mencionaron más usos históricos y actuales de la especie. El 60% de los hombres manifestaron haber avistado a Rhea tarapacensis en el último año. Teniendo en cuenta los usos para obtención de carne y plumas y los usos medicinales reconocidos, la presión de caza sobre la población de Rhea tarapacensis podría no estar debidamente considerada en la evaluación de su situación de amenaza. Esto hace necesario un monitoreo continuo de la especie en la región, incluyendo el área protegida, acompañado de la realización de programas de difusión y uso sustentable dirigidos a los pobladores para efectivizar su conservación.Rhea tarapacensis is a threatened species ecologically extinct in part of its distribution range. It is one of the species most used in traditional medicine in the vicinity of the San Guillermo Biosphere Reserve (San Juan, Argentina), and its recognition by residents, the common names it receives and other historical and current uses still remain to be assessed. This study was carried out at four locations close to the reserve. A total of 171 semi-structured interviews were conducted with residents of both sexes, older than age 15, who have different activities and educational levels. Ninety five percent of the people recognized Rhea tarapacensis, which is locally called Avestruz, Chure, Churi or Ñandú.Contributors mentioned a strong historical use of its meat and feathers, and a lower but still important current use. Men, people between 31–45 years old and the residents of Tudcum were the ones who mentioned more historical and current uses of this species. Sixty percent of men claimed to have sighted Rhea tarapacensis over the past year. Considering the uses for obtaining meat and feathers and the recognized medicinal uses, the hunting pressure on Rhea tarapacensis could not be properly considered in the current evaluation of its conservation status. This makes necessary a continuous monitoring of the species in the region, including the protected area, accompanied by the implementation of programs of education and sustainable use directed to the residents, targeted at its conservation

Coordenação de graduação: competências requeridas conforme o processo gerencial

This study aimed to link the necessary competencies to the post of management of undergraduate courses with the four essential phases of the management process: planning, organization, direction, and control. The available scientific literature was analyzed, organized based on semantic and content analysis techniques so that the answers to the guiding questions previously formulated could be visualized. The study points out that the undergraduate coordinator needs to master knowledge from other areas of expertise to act, such as a) analyzing scenarios and generating course production; b) management of materials and services infrastructure, c) leadership, communication, and motivation of your team, and d) assessment of the quality of work and production performed.Neste texto relata-se resultados de estudo que teve por objetivo vincular as competências necessárias ao cargo de gerência de graduações com as quatro fases básicas do processo de gestão: planejamento, organização, direção e controle. Analisou-se a literatura disponível, organizada com base nas técnicas de análises semântica e de conteúdo, para que pudessem ser visualizadas as respostas às questões norteadoras previamente formuladas. Entendeu-se que o coordenador de graduações precisa dominar conhecimentos de outras áreas do conhecimento para atuar, tais como análise de cenários e geração de produção do curso; gestão de infraestrutura de materiais e serviços, liderança, comunicação e motivação do seu time e aferição da qualidade do trabalho e da produção realizada

Thermal plasticity of the miRNA transcriptome during Senegalese sole development

Several miRNAs are known to control myogenesis in vertebrates. Some of them are specifically expressed in muscle while others have a broader tissue expression but are still involved in establishing the muscle phenotype. In teleosts, water temperature markedly affects embryonic development and larval growth. It has been previously shown that higher embryonic temperatures promoted faster development and increased size of Senegalese sole (Solea senegalensis) larvae relatively to a lower temperature. The role of miRNAs in thermal-plasticity of growth is hitherto unknown. Hence, we have used high-throughput SOLiD sequencing to determine potential changes in the miRNA transcriptome in Senegalese sole embryos that were incubated at 15°C or 21°C until hatching and then reared at a common temperature of 21°C. Results: We have identified 320 conserved miRNAs in Senegalese sole, of which 48 had not been previously described in teleosts. mir-17a-5p, mir-26a, mir-130c, mir-206-3p, mir-181a-5p, mir-181a-3p and mir-199a-5p expression levels were further validated by RT- qPCR. The majority of miRNAs were dynamically expressed during early development, with peaks of expression at pre-metamorphosis or metamorphosis. Also, a higher incubation temperature (21°C) was associated with expression of some miRNAs positively related with growth (e.g., miR-17a, miR-181-5p and miR-206) during segmentation and at hatching. Target prediction revealed that these miRNAs may regulate myogenesis through MAPK and mTOR pathways. Expression of miRNAs involved in lipid metabolism and energy production (e.g., miR-122) also differed between temperatures. A miRNA that can potentially target calpain (miR-181-3p), and therefore negatively regulate myogenesis, was preferentially expressed during segmentation at 15°C compared to 21°C. Conclusions: Temperature has a strong influence on expression of miRNAs during embryonic and larval development in fish. Higher expression levels of miR-17a, miR-181-5p and miR-206-3p and down-regulation of miR-181a-3p at 21°C may promote myogenesis and are in agreement with previous studies in Senegalese sole, which reported enhanced growth at higher embryonic temperatures compared to 15°C. Moreover, miRNAs involved in lipid metabolism and energy production may also contribute to increased larval growth at 21°C compared to 15°C. Taken together, our data indicate that miRNAs may play a role in temperature-induced phenotypic plasticity of growth in teleosts.Peer Reviewe

Association between the histopathologic findings of a zero-time biopsy and the donor kidney function 24 hours and a year after nephrectomy

Background: The living-donor transplantation (LDT) is essential to provide patients with chronic kidney disease (CKD) a superior quality of life and improve their lifespan. Recent investigations prove that the living donors (LD) have a risk of developing CKD, without there being a way to anticipate it. The zero-time biopsies provide valuable information that may contribute to this objective since they report histopathologic findings of subclinical chronic damage. Methods: Retrospective, observational and analytical study. The information from the medical files and pathology department of LD attended at “Dr. Miguel Silva” general hospital from January 2006 to January 2018 was analyzed. The glomerular filtrate rate was obtained 24 hours and a year after nephrectomy and was estimated based on CDK-EPI. The comparison among groups was made through Mann-Whitney testing for continuous numeric. A value of p36 years, the dropping of the GFR >43%, the GFR and the creatinine levels after 24 hours of nephrectomy were associated with a reduction of the GFR the year after nephrectomy

Oral signs of intravenous chemotherapy with 5- Fluorouracil and Leucovorin calcium in colon cancer treatment

Several studies have shown how cytostatics may cause hypofunction of salivary glands but failed to elucidate any potentially related side effects. Keeping in mind the sialochemical assistance and the role of saliva on the homeostasis of the stomatognathic system, the aim of this study was to establish potential gland disorders in patients submitted to 5- Fluorouracil (5-Fu) and Leucovorin calcium(LV) as well as their correlation with certain oral health disorders that diminish the quality of life. Materials and methods: the focus of this research was observational and longitudinal. Twenty-five patients diagnosed with colon cancer at an initial, intermediate and late phase submitted to specifically devised therapy were assessed. Clinical history, oral health indexes and basal or stimulated saliva samples were recorded. Results: Basal and stimulated flow dropped in the intermediate stage. Stimulated saliva pH decreased during treatment. On basal saliva, urea, sodium and potassium rose during the intermediate phase. Löe and Silness rates as well as simplified bleeding increased during therapy but reverted by the end of the treatment. Depth index of the vestibular gingival sulcus rose during the intermediate phase but did not return. Conclusion: This treatment caused functional salivary gland disorders as evidenced by basal and stimulated hyposialia, and acidification of stimulated saliva pH during the intermediate phase. Increase in basal urea may be due to proteic catabolism arising from plasma or glands. Variation in Na+ and K+ of basal saliva concentrates might be assumed as a possible duct disorder. Recovery of bleeding and Löe and Silness rates may point to a transient inflammatory effect associated to a decrease in salivary flow. Increase in the depth rates of the periodontal vestibular sulcus could be correlated with a higher risk of periodontal disease