Master of Science

This thesis incorporates two different studies investigating occupational exposure to ionizing radiation in veterinary workers. The first study evaluated the frequency of use of protective eyeglasses and gloves, and the frequency of protective behaviors (increasing distance from the body and head eye region to the radiation source), during manual restraint for radiography among small animal workers in a veterinary hospital before and after a video training module. In the second study we evaluated self-reported radiation safety behaviours among small animal veterinary diplomate and resident fluoroscopy users through an electronic questionnaire. The first study demonstrated a significant improvement in all behavior outcomes after the video training (vs before), and also found that sedation or anesthesia reduce the need for workers to be inside the radiography room manually restraining the animal; however, the overall frequency of optimal behaviors was still low. The second study found a low eyeglasses and hand shielding compliance among veterinary fluoroscopy users. Both studies demonstrated that workers with formal training in radiation safety are more likely to adopt behaviours that reduce their dose, such as PPE compliance. In conclusion, this thesis work found that education and formal training on radiation safety increases behaviours that decrease worker dose and help to develop a radiation safety culture in the workplace. However, it also found a low compliance of protective eyeglasses and gloves among veterinary radiology and fluoroscopy users. Finally, sedation or anesthesia should be used more often during diagnostic radiography as it reduces the need for workers to be inside the radiography room, thus reducing their radiation exposure

Concentração Regional do Crédito e Consolidação Bancária no Brasil: Uma Análise Pós-Real

O objetivo deste artigo é analisar como o processo de consolidação bancária brasileiro, a partir da implementação do Plano Real, impactou a distribuição e concessão do crédito regionalmente. A partir da análise de dados estatísticos e da utilização da análise de dados em painel, avaliamos as implicações desse processo sobre o comportamento do setor bancário e seus efeitos sobre a concessão e distribuição de crédito regional. Os resultados obtidos no exercício empírico para o período 1994-2006 mostram indícios a favor da hipótese de que o processo de reestruturação bancária teve efeito negativo sobre a disponibilidade regional do crédito, sobretudo nas regiões periféricas do País. Adicionalmente, há evidências de que fatores monetários são importantes na explicação da tendência a concentração regional do crédito no Brasil.Oferta de Crédito, Economia Regional, Setor Bancário Brasileiro.

Importância da avaliação clínica, anatomopatológica e imuno-histoquímica para o diagnóstico diferencial das neoplasias mesenquimais gastrointestinais não hematopoiéticas em cães: revisão de literatura

As neoplasias gastrointestinais em cães representam casos desafiantes ao clínico e cirurgião, pois são em sua maioria malignas e, quando as primeiras alterações clínicas são notadas pelo proprietário do animal, a doença pode estar em estágio de desenvolvimento muito avançado. Devido à elevada similaridade clínica e histopatológica entre as neoplasias gastrointestinais mesenquimais, muitas vezes não é possível estabelecer o diagnóstico morfológico definitivo apenas com a microscopia de luz. Acrescenta-se que são poucos os artigos que descrevem as características anatomopatológicas e imuno-histoquímicas das neoplasias mesenquimais gastrointestinais que acometem os cães, o que torna premente a caracterização destas em nosso contexto, com o intuito de auxiliar clínico, cirurgião e patologista veterinário a estabelecer o diagnóstico destes tumores.Gastrointestinal neoplasms in dogs represent a challenge for the veterinary clinician and surgeon as they are mostly malignant and when the owner notices the primary clinical changes the disease may already be in an advanced stage. Due to the high clinical and histopathological similarity between mesenchymal gastrointestinal neoplasms, it is often impossible to establish the definitive morphological diagnosis using light microscopy alone. In addition, there are only a few articles describing the anatomopathological and immunohistochemical characteristics, which make its complete characterization urgent and relevant in our context in order to assist the veterinary clinician, surgeon, and pathologist in establishing a precise diagnosis of these tumors

Antioxidant Migration Studies in Chitosan Films Incorporated with Plant Extracts

This work was supported by CNPq/Brazil (grant number 200790/2014-5); CAPES (APQ-1 2009/02 E-26/110.414/2010, APQ-1 2011-2 E-26/110.269.2012, E-26/111.435/2012 - CsF/Brazil - BEX 11943-13-0); CENIMAT/I3N and MEtRiCS through FCT/MCTES (project number and UID/SEM/04077/2013CN).The aim of this work was to develop an active biopolymer based on chitosan by incorporating natural antioxidants. Five essential oils (ginger, rosemary, sage, tea tree and thyme) and six hydro-alcoholic extracts (from ginger, green and black tea, kenaf leaves, rosemary and sage plants) were tested. Migration assays were carried out to evaluate the films’ activity, and total phenolic content and antioxidant activity were monitored in the simulant during storage. Interaction between natural compounds and polymeric matrix was evaluated by FTIR spectroscopy. The diffusion of the phenolic compounds was not detected in the films incorporated with hydro-alcoholic extracts (HAEs), indicating their entrapment in the chitosan. Migration was observed in the films with essential oils (EOs), and biobased films incorporated with ginger, sage or rosemary essential oils, presented the highest diffusion and antioxidant activity in the simulant, highlighting their functionality and potential to be used as food active packaging materialpublishersversionpublishe

Photochemistry of 5-Hydroxy-4'-Dimethylaminoflavylium in the presence of SDS micelles. The role of metastable states of flavylium cation-quinoidal base and trans-chalcones

UIDB/50006/2020 UIDP/50006/2020 PTDC/QUI-OUT/29013/2017 SFRH/BD/143309/2019 SFRH/BD/146549/2019 MEX/Ref. 288188 IF/00225/2015The multistate of species originated by the compound 5-hydroxy-4′-dimethylaminoflavylium was studied in the presence of sodium dodecyl sulfate micelles 0.1 M. A series of pH jumps obtained by addition of base to the equilibrated solutions of the flavylium cation results in a metastable equilibrium between the flavylium cation and the quinoidal base with pKa = 7.6. In neutral to moderately basic medium, only at 60 °C and after 5 days a new distribution involving the flavylium cation and trans-chalcones is achieved. On the other hand, the anionic trans-chalcone can be formed in few minutes in very basic medium at room temperature and from this, another meta-stable state constituted by protonated, neutral and anionic trans-chalcones, pKCt+/Ct = 2.6 and pKCt/Ct- = 10.7 is reached. The equilibrium is apparently attained between flavylium cation, neutral and anionic trans-chalcones respectively for pKAH+/Ct = 4.1 and pKCt/Ct- = 10.7. Irradiation of the neutral (stable or metastable) and protonated (meta-stable) trans-chalcones yields to the appearance of the quinoidal base or the flavylium cation in an extended pH region 1 < pH < 10. The peculiar properties of this flavylium based photochromic system are explained by means of an energy level diagram where cis-chalcone and hemiketal lay above the quinoidal base.authorsversionpublishe

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