Avaliação de progênies de Eucalyptus crebra no norte do Estado de Goiás.

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Evidence for entanglement at high temperatures in an engineered molecular magnet

The molecular compound [Fe$_{2}$($\mu_{2}$-oxo)(C$_{3}$H$_{4}$N$_{2}$)$_{6}$(C$_{2}$O$_{4}$)$_{2}$] was designed and synthesized for the first time and its structure was determined using single-crystal X-ray diffraction. The magnetic susceptibility of this compound was measured from 2 to 300 K. The analysis of the susceptibility data using protocols developed for other spin singlet ground-state systems indicates that the quantum entanglement would remain at temperatures up to 732 K, significantly above the highest entanglement temperature reported to date. The large gap between the ground state and the first-excited state (282 K) suggests that the spin system may be somewhat immune to decohering mechanisms. Our measurements strongly suggest that molecular magnets are promising candidate platforms for quantum information processing

Morphology, mechanical characterization and in vivo neo-vascularization of chitosan particle aggregated scaffolds architectures

The present study intended to evaluate the performance of chitosan-based scaffolds produced by a particle aggregation method aimed to be used in tissue engineering applications addressing key issues such as morphological characteristics, mechanical performance and in vivo behaviour. It is claimed that the particle aggregation methodology may present several advantages, such as combine simultaneously a high interconnectivity with high mechanical properties that are both critical for an in vivo successful application. In order to evaluate these properties, micro-Computed Tomography (micro-CT) and Dynamical Mechanical Analysis (DMA) were applied. The herein proposed scaffolds present an interesting morphology as assessed by micro-CT that generally seems to be adequate for the proposed applications. At a mechanical level, DMA has shown that chitosan scaffolds have an elastic behaviour under dynamic compression solicitation, being simultaneously mechanically stable in the wet state and exhibiting a storage modulus of 4.21 ! 1.04 MPa at 1 Hz frequency. Furthermore, chitosan scaffolds were evaluated in vivo using a rat muscle-pockets model for different implantation periods (1, 2 and 12 weeks). The histological and immunohistochemistry results have demonstrated that chitosan scaffolds can provide the required in vivo functionality. In addition, the scaffolds interconnectivity has been shown to be favourable to the connective tissues ingrowth into the scaffolds and to promote the neo-vascularization even in early stages of implantation. It is concluded that the proposed chitosan scaffolds produced by particle aggregation method are suitable alternatives, being simultaneously mechanical stable and in vivo biofunctional that might be used in load-bearing tissue engineering applications, including bone and cartilage regeneration.The authors would like to acknowledge the Portuguese Foundation for Science and Technology for the PhD Grant to Patricia B Malafaya (SFRH/BD/11155/2002). This work was partially supported and carried out under the scope of the European STREP Project HIPPOCRATES (NMP3-CT-2003-505758) and European NoE EXPERTISSUES (NMP3-CT-2004-500283). The authors also thank Prof. Heinz Redl for the collaboration in the in VIVO Studies, as well as Bernhard Horing for the surgical procedures both from LBI, Austria and Joao Oliveira from 3B's Research Group, Portugal for the initial assistance with the DMA equipment

Sistemas de rotação de culturas com trigo para a região sul do Brasil.

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ANÁLISE DA QUALIDADE DO SERVIÇO: UMA APLICAÇAO DO MODELO SERPERF EM DUAS AGÊNCIAS BANCÁRIAS DE CAMPOS DOS GOYTACAZES

Em um ambiente de grande competitividade e constantes instabilidades, as empresas buscam formas inovadoras para atrair e manter seus clientes. A diferenciação destas empresas reside em um atendimento qualificado, tornando esse fator determinante na sobrevivência no mercado, utilizando dessa postura de aproximação com os clientes como estratégia para manter-se lucrativos. Nesse contexto, as empresas precisam suprir os interesses e necessidades de seus stakeholders, pois satisfação reflete seus compromissos com ética e princípios moralmente aceitos pelas comunidades (SANTOS, 2011). O Objetivo deste trabalho de consiste em avaliar o desempenho do serviço prestado por agências bancaria da região Norte Fluminense, utilizando a ferramenta SERVPERF, segundo a percepção dos usuários e gestores. O SERVPERF é o modelo desenvolvido por Cronin e Taylor (1992) para avaliar o desempenho dos serviços prestados, levando em consideração a visão dos clientes. Segundo Junior e Bornia (2011) o SERVPERF utiliza apenas a qualidade percebida na avaliação da satisfação. Já Salomi, Miguel e Abackerli (2005) concluem que o instrumento SERVPERF é mais sensível em retratar as variações de qualidade em relação às outras escalas. A abordagem metodológica deste artigo consiste na coleta de dados primários, de forma quantitativa por meio de questionários de questões fechadas, entregue aos clientes de duas agências de Campos dos Goytacazes. A amostra da pesquisa será composta por 100 clientes de duas agências bancárias do município de Campos dos Goytacazes. Segundo Vicente, Junior e Hora (2014) os dados constantes nos questionários respondidos pelos clientes das agências bancárias serão utilizados não apenas para comprovar a hipótese do bom atendimento ou não da empresa analisada, mas também será usada para a elaboração de gráficos sobre o nível de desempenho do atendimento prestado por essa empresa do setor bancário em Campos dos Goytacazes. A elaboração do questionário foi realizada por meio da adaptação do modelo utilizado pelos autores Junior e Bornia (2011). O questionário é composto por 35 questões das quais espera-se que, após a conclusão da pesquisa seja possível identificar critérios importantes e inerentes a qualidade do desempenho dos serviços prestados nas agências bancárias. Para a composição do questionário, foram selecionadas as seguintes dimensões da qualidade em serviços que compõe o modelo SERVPERF: I) Confiabilidade - Prestar serviço como prometido, com precisão consistência e segurança; II) Rapidez - Velocidade de atendimento e prontidão para atender o cliente; III) Tangíveis – Refere-se a quaisquer evidenciais físicas do serviço, como instalações físicas, aparência dos funcionários e equipamentos utilizados no processo; Empatia - Cordialidade, cuidados e atenções individual fornecidas ao cliente; IV) Flexibilidade - Capacidade de mudar e adaptar o serviço para se ajustar as necessidades dos clientes; V) Acesso - Facilidade de entrar em contato ou acessar fisicamente os serviço; Disponibilidade - Facilidade de encontrar disponível pessoal de atendimento, bens, facilitadores e instalações. Espera-se que por meio da elaboração do questionário e seleção das dimensões estudadas, possa seja apurado o grau do desempenho dos serviços prestados pelas agências estudadas

Natural origin scaffolds with in situ pore forming capability for bone tissue engineering applications

This work describes the development of a biodegradable matrix, based on chitosan and starch, with the ability to form a porous structure in situ due to the attack by specific enzymes present in the human body (a-amylase and lysozyme). Scaffolds with three different compositions were developed: chitosan (C100) and chitosan/starch (CS80-20, CS60-40). Compressive test results showed that these materials exhibit very promising mechanical properties, namely a high modulus in both the dry and wet states. The compressive modulus in the dry state for C100 was 580 ± 33 MPa, CS80-20 (402 ± 62 MPa) and CS60-40 (337 ± 78 MPa). Degradation studies were performed using a-amylase and/or lysozyme at concentrations similar to those found in human serum, at 37 C for up to 90 days. Scanning electron micrographs showed that enzymatic degradation caused a porous structure to be formed, indicating the potential of this methodology to obtain in situ forming scaffolds. In order to evaluate the biocompatibility of the scaffolds, extracts and direct contact tests were performed. Results with the MTT test showed that the extracts of the materials were clearly non-toxic to L929 fibroblast cells. Analysis of cell adhesion and morphology of seeded osteoblastic-like cells in direct contact tests showed that at day 7 the number of cells on CS80-20 and CS60-40 was noticeably higher than that on C100, which suggests that starch containing materials may promote cell adhesion and proliferation. This combination of properties seems to be a very promising approach to obtain scaffolds with gradual in vivo pore forming capability for bone tissue engineering applications.This work was supported by the European NoE EXPERTISSUES (NMP3-CT-2004-500283), the European STREP HIPPOCRATES (NMP3-CT-2003-505758) and the Portuguese Foundation for Science and Technology (FCT) through POCTI and/or FEDER programmes

Morphometric and mechanical characterization, insulin loading and in-vivo biocompatibility of chitosan particles aggregated scaffolds for tissue engineering

In tissue engineering, scaffolds development presents, among others, 3 key requirements: adequate morphological characteristics, mechanical performance and in-vivo biocompatibility. The aim of the present study was to evaluate chitosan-based scaffolds produced by particle aggregation in these key issues. Furthermore, chitosan scaffolds were loaded with insulin to promote chondrogenic differentiation. Micro-Computed Tomography (m-CT) was carried out for accurate morphometric characterization quantifying porosity, interconnectivity, particles and pores size that shown to be adequate. Dynamical Mechanical Analysis (DMA) showed that scaffolds are mechanically stable in wet state with a storage modulus of 4.21 1.04 MPa at 1Hz frequency. Insulin-loaded scaffolds were characterized and studied with a pre-chondrogenic cell line (ATDC-5). The in-vitro release was carried out mimicking cell culture conditions quantified by micro-BCA. [...]info:eu-repo/semantics/publishedVersio

Breaking Barriers: Bioinspired Strategies for Targeted Neuronal Delivery to the Central Nervous System

Central nervous system (CNS) disorders encompass a vast spectrum of pathological conditions and represent a growing concern worldwide. Despite the high social and clinical interest in trying to solve these pathologies, there are many challenges to bridge in order to achieve an effective therapy. One of the main obstacles to advancements in this field that has hampered many of the therapeutic strategies proposed to date is the presence of the CNS barriers that restrict the access to the brain. However, adequate brain biodistribution and neuronal cells specific accumulation in the targeted site also represent major hurdles to the attainment of a successful CNS treatment. Over the last few years, nanotechnology has taken a step forward towards the development of therapeutics in neurologic diseases and different approaches have been developed to surpass these obstacles. The versatility of the designed nanocarriers in terms of physical and chemical properties, and the possibility to functionalize them with specific moieties, have resulted in improved neurotargeted delivery profiles. With the concomitant progress in biology research, many of these strategies have been inspired by nature and have taken advantage of physiological processes to achieve brain delivery. Here, the different nanosystems and targeting moieties used to achieve a neuronal delivery reported in the open literature are comprehensively reviewed and critically discussed, with emphasis on the most recent bioinspired advances in the field. Finally, we express our view on the paramount challenges in targeted neuronal delivery that need to be overcome for these promising therapeutics to move from the bench to the bedside.This work was financially supported by the project PTDC/CTM-NAN/3547/2014 (POCI-01-0145-FEDER-016639) funded by FEDER funds through the Programa Operacional Competitividade e Internacionalização-COMPETE 2020 and Portuguese funds through FCT–Fundação para a Ciência e a Tecnologia. A.P.S., B.C. and S.D.S. acknowledge FCT for the Ph.D. scholarships (SFRH/BD/137073/2018 and SFRH/BD/145652/2019) and the contract under the Norma Transitória–DL57/2016/CP/CP1360/CT0013, respectively. V.L. acknowledges her contract in the framework of the project NORTE-01-0247-FEDER-033399, funded by FEDER funds through the Sistema de Incentivos à Investigação e Desenvolvimento Tecnológico (SI I&DT), Aviso nº 03/SI/2017, Projetos em Co-promoção do Programa Interfac