Kinetic Monte Carlo simulation of the nitridation of the GaAs (100) surfaces

We present, in this work, our preliminary results of a systematic theoretical study of the adsorption of N over As-terminated GaAs (100) (2$\times$1) surfaces. We analyzed the changes in the bond-lenghts, bond-angles and the energetics involved before and after deposition. Our results show that the N-atoms will prefer the unoccupied sites of the surface, close to the As dimer. The presence of the N pushes the As dimer out of the surface, leading to the anion exchange between the N and As atoms. Based on our results, we discussed about the kinetics of the N islands formation during epitaxial growth of the III-Nitrides.Comment: 4 pages, 7 figures, accepted for publication in Braz. J. Phys., special number, Proceedings of BWSP-12, 12th Brazilian Workshop on Semiconductor Physic

A third sector in the core-periphery model: non-tradable goods

We extend an analytically solvable core-periphery model by introducing a monopolistically competitive sector of non-tradable goods. We study how trade costs affect the spatial distribution of economic activity. Trade costs have no effect when the elasticity of substitution among non-tradable goods is low. In this case, concentration of all production (of tradable and non-tradable goods) is the unique equilibrium. When the elasticity of substitution among non-tradable goods is high, we find two equilibrium configurations: symmetric dispersion of the production of tradable and non-tradable goods, if trade costs are high; and concentration of production of tradable goods with asymmetric dispersion of production of non-tradable goods, if trade costs are low.New economic geography, Core-periphery model, Footloose entrepreneur, Nontradable goods

The core periphery model with asymmetric inter-regional and intra-regional trade costs

We generalize the model of Krugman (1991) to allow for asymmetric trade costs between regions and for (asymmetric) trade costs that are internal to the regions. We find that industrial activity, in a region, is enhanced by higher costs of importing and lower costs of exporting (more precisely, by a higher ratio between the two trade costs). This suggests that countries may impose tariffs on imported goods and seek to remove the import tariffs in other countries (unilateral protectionism) in order to foster industrial activity. Industrial activity is also promoted by lower domestic internal trade costs and higher foreign internal trade costs (more precisely, by a lower ratio between the two trade costs).New Economic Geography, Core-Periphery, Trade costs, Unilateral protectionism.

Extensive oral melanoma on the hard palate: case report

Trabalho de Conclusão de Curso (Graduação)Oral mucosa melanoma (OMM) is a rare malignant neoplasm of aggressive character, and it accounts for fewer than 1% of malignant oral lesions. This paper presents a case of OMM manifesting as a large focal pigmentation on the hard palate. A 54-year-old male patient was referred by a general dentist for specific assessment of the detected lesion. During anamnesis, the patient reported smoking for twenty years and abstaining from the habit for twenty years. On oral examination, a focal black pigmentation with red areas was observed in the median region of the hard palate, extending from the canine to upper second molars region. The diagnostic hypothesis was OMM. Upon incisional biopsy, the tissue fragment revealed mucosa covered by stratified epithelial tissue and partially ulcerated, as well as the presence of neoplasia containing melanin pigments, compatible with OMM. After diagnostic confirmation, the patient was referred to the head and neck surgery service of the local cancer center, where 27 sessions of radiotherapy and 4 sessions of brachytherapy were performed. Systematic clinical examinations of the oral cavity for the detection of asymptomatic and isolated pigmentations are necessary, and it is important to improve dentists' knowledge of the nature of these lesions, since early diagnosis is essential to increase the chances of curing this aggressive malignancy

Robotics and their impact in Healthcare Workforce Management

New technologies are increasingly appearing across all sectors. In healthcare, the implementation and growth of robotics is already a reality in several hospitals and is expected to grow exponentially in the coming years. Therefore, organizations have to prepare and rethink their human resources strategies and activities to cope with this new thematic. This qualitative case study focuses on understanding in what extent hospitals are or are not preparing their workforce for the implementation of robots. Through the combination of the existing literature and the interviews conducted, it was possible to identify that there is a clear distinction between the public and private sectors regarding the implementation and growth of robotics in the healthcare sector. While the private sector invests in training, reorganization of teams and creation of taskforces, the public sector does not have as a priority to rethink its human resources strategies and activities because the Public Ministry does not do or plan to do, in the short term, any kind of investment in robotics. Moreover, the fear of losing the human side with the patient allied to the fear of robots replacing human delays the implementation of robotics in hospitals. There are still some workers who are resilient to change and not very supporters of new technologies. This thesis aims to give recommendations to different stakeholders and identifies future opportunities to study the impact of robotics on the workforce.Cada vez mais tem aparecido novas tecnologias transversalmente a todos os setores. Na saúde, a implementação e o crescimento da robótica já é uma realidade em vários hospitais e prevê se que cresça exponencialmente nos próximos anos. Por isto, as organizações têm de preparar e repensar as suas estratégias e atividades de recursos humanos para fazerem face a esta nova temática. Este caso de estudo qualitativo foca-se em perceber até que ponto é que os hospitais estão ou não a preparar a sua força-de-trabalho para a implementação de robôs. Através da combinação da literatura existente e das entrevistas realizadas, foi possível identificar que existe uma clara distinção entre o setor pulico e o setor privado no que toca a implementação e crescimento da robótica no setor da saúde. Enquanto o setor privado investe em formação, reorganização das equipas e criação de taskforces, o setor publico não tem como prioridade repensar as suas estratégias e atividades de recursos humanos porque o Ministério Público não faz nem prevê fazer, no curto prazo de tempo, qualquer tipo de investimento em robótica. Ainda mais, o medo de se perder o lado humano com o paciente aliado ao medo dos robôs substituírem os humanos atrasa a implementação de robótica em hospitais. Ainda há alguns trabalhadores resilientes à mudança e pouco adeptos a novas tecnologias. Esta tese visa dar recomendações aos diferentes stakeholders e identifica futuras oportunidades de estudo do impacto da robótica na força de trabalho

Tradução e adaptação transcultural do World Health Organization Disability Assessment Schedule - WHODAS 2.0

A Organização Mundial da Saúde (OMS) planejou uma nova ferramenta de aferição da funcionalidade - o WHODAS 2.0 (World Health Assessment Disability Schedule 2.0) - um instrumento de aplicação facilitada e baseado no modelo teórico da CIF. Este artigo busca introduzir a versão brasileira do WHODAS para usuários clínicos e acadêmicos interessados na aferição da funcionalidade. O processo foi conduzido de acordo com o Translation Package, oferecido pela OMS, junto com a permissão para tradução do material. Três tradutores trabalharam nesse projeto para produzir a versão final do manual e um conjunto de formulários de avaliação linguística. Em seguida, a versão brasileira foi aprovada pela OMS. Todos os documentos sobre o WHODAS foram traduzidos e estão disponíveis gratuitamente na internet. WHODAS 2.0 aborda a funcionalidade de acordo com os domínios da CIF e mantém a perspectiva multifatorial e biopsicossocial. Como diferencial da CIF, a coleta de dados com o WHODAS é mais rápida (aproximadamente 20 minutos) e mais objetiva. Além disso, ele foi planejado para ser uma ferramenta genérica e transcultural. WHODAS foi traduzido e disponibilizado na internet. É esperado que o uso do WHODAS se dissemine pelo país, em ambientes clínicos e de pesquisa, buscando a abordagem biopsicossocial da funcionalidade, conforme endossado pela OMS.La Organización Mundial de la Salud (OMS) planeó una nueva herramienta de medición de la funcionalidad, la WHODAS 2.0 (World Health Assessment Disability Schedule 2.0) -un instrumento de aplicación basado en el modelo teórico de la CIF. Este artículo busca introducir la versión brasileña de la WHODAS para los usuarios clínicos y académicos interesados en la medición de la funcionalidad. Se realizó el proceso de acuerdo al Translation Package, ofrecido por la OMS, en asociación con el permiso para traducir el material. Tres traductores trabajaron en este proyecto para producir la versión final del manual y un conjunto de formularios de evaluación lingüística. Luego, OMS aprobó la versión brasileña. Todos los documentos sobre WHODAS han sido traducidos y están disponibles libremente en Internet. WHODAS 2.0 trata de la funcionalidad de acuerdo a los dominios de la ICF y mantiene la perspectiva multifactorial y biopsicosocial. Es un diferencial de la ICF la recolección más rápida de datos con el WHODAS (aproximadamente 20 minutos) y más objetiva. Además, ha sido planeado para ser una herramienta genérica y transcultural. WHODAS ha sido traducida y está disponible en Internet. Se espera que el uso de la WHODAS se propague en el país, en ambientes clínicos y de investigación, buscándose en abordaje biopsicosocial de la funcionalidad, según lo endosado por la OMS.The World Health Organization (WHO) planned a new functioning assessment tool - the WHODAS 2.0 (World Health Assessment Disability Schedule 2.0) - a user-friendly application instrument based on the theoretical framework of the ICF. The aim of this article is to introduce the Brazilian version of WHODAS to clinical and academic users interested in the assessment of functioning. The process was conducted according to the Translation Package offered by WHO, in addition to the permission for translating the tool. Three translators worked in this research to produce the definitive version of the manual and a set of linguistic evaluation forms. Finally, the Brazilian version was approved by WHO. All documents about WHODAS were translated and are free to download on the internet. WHODAS 2.0 addresses functioning according to the ICF domains and keeps the multifactorial and biopsychosocial perspective of the phenomenon. As it has an ICF differentiate presentation, the data collection is faster (20 minutes, on average) and more objective. Besides, it was planned to be a generic and transcultural tool. WHODAS was translated and is available on Internet to use. It is expected that the use of WHODAS will be widespread in Brazil, in clinical and research settings, aiming at the biopsychosocial approach of the functioning, as endorsed by WHO

The impact on our valuation when changing critical inputs

In this part I present a scenario analysis on our valuation. In fact, our valuation in highly dependent on four inputs, which we forecast a behavior for them, that we are not sure will happen. Therefore, I used our valuation as a base case scenario, which I gave a probability of 60%. Moreover, I also did a best and worst case scenario, giving 20% of probability of occurrence to which one

Aplicação da tecnologia de homogeneização à alta pressão na modificação de enzimas coagulantes do leite

Orientadores: Marcelo Cristianini, Alline Artigiani Lima TribstDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de AlimentosResumo: A homogeneização à alta pressão (HAP) é um processo capaz de alterar a conformação e funcionalidade de enzimas. Os objetivos deste trabalho foram: (i) avaliar a influência da HAP até 190 MPa nas atividades proteolítica e de coagulação do leite bem como na estabilidade de quatro enzimas coagulantes do leite, (ii) acompanhar o processo de coagulação por ensaios reológicos e (iii) avaliar o desenvolvimento dos géis por 24 horas por meio das análises de proteólise, sinérese, reologia e microscopia. As avaliações foram feitas comparando-se os resultados obtidos com as enzimas processadas e não processadas. O coalho de vitelo processado a 190 MPa apresentou redução de 52% na atividade proteolítica, aumento da taxa de coagulação do leite e gel formado mais consistente. A avaliação deste gel por 24h indicou a formação de uma rede proteica com menor proteólise, maior sinérese, maior consistência e menor porosidade. Após processamento a 150 MPa, o coalho de bovino adulto apresentou redução da atividade proteolítica, aumento da atividade e estabilidade de coagulação do leite, maior taxa de coagulação do leite e formação de gel com maior consistência. O gel se mostrou mais compacto, firme e com maior expulsão do soro da matriz proteica nas 24h em que foi avaliado. A protease fúngica do Rhizomucor miehei foi a enzima mais resistente ao processo de HAP, sofrendo mínima ou nenhuma alteração na atividade proteolítica e de coagulação do leite quando processada até 190 MPa em diferentes concentrações e em múltiplos processos consecutivos. Entretanto, na avaliação reológica da coagulação do leite utilizando-se a protease fúngica homogeneizada a 190 MPa por até 3 ciclos ou quando homogeneizada a 190 MPa em soluções com concetração de 20 % foi observado aumento da consistência do gel. Para pepsina suína, as alterações na atividade proteolítica e de coagulação do leite só foram observadas durante a estocagem, com redução na atividade proteolítica e um aumento na atividade de coagulação do leite para enzima processada a 150 MPa. No entanto, esta enzima processada promoveu uma coagulação do leite mais rápida formando um gel mais consistente, mesmo imediatamente após o processamento por HAP. Durante a observação deste gel por 24h, este se mostrou mais compacto, firme, menos poroso e com maior liberação de soro da matriz proteica. De uma forma geral foi possível concluir que as maiores pressões aplicadas (150 MPa e 190 MPa) afetaram positivamente as enzimas avaliadas, com redução da atividade proteolítica inespecífica e aumento da atividade de coagulação de leite, com consequente formação de géis com menores níveis de proteólise, o que favorece a manutenção da rede proteica rígida, firme e coesa. Desta forma, conclui-se que a HAP é um processo promissor que pode ser aplicado como uma tecnologia para melhorar as características hidrolíticas das enzimas coagulantes do leite, especialmente quando se deseja diminuir atividade proteolítica e aumentar sua atividade de coagulação do leite. Além disso, a menor proteólise no gel pode resultar numa extensão da vida de prateleira de queijos frescos, por, possivelmente, reduzir a formação de compostos de sabor indesejávelAbstract: High pressure homogenization (HPH) is a process that can alter the conformation and functionality of enzymes. The objectives of this study were: (i) evaluate the influence of HPH up to 190 MPa on the proteolytic and milk-clotting activities and stability of four milk-clotting enzymes, (ii) monitor the coagulation process by rheological assays and (iii) evaluate the gel development for 24 hours analyzing proteolysis, syneresis, rheological and microstructural behavior. The evaluations were performed by comparing the results between the processed and non-processed enzymes. The calf rennet processed at 190 MPa decreased 52 % its proteolytic activity, increased the rate of milk-clotting and a more consistent gel was formed. The evaluation of the gel for 24 hours indicated the formation of a protein network with lower proteolysis, higher syneresis, higher consistency and lower porosity. After processing at 150 MPa adult bovine rennet showed a reduction proteolytic activity, increase activity and stability of milk-clotting, higher milk-clotting rate and formed more consistent gels. This gel was more compact, firm and higher whey separation of protein matrix during the 24 hours of evaluation. The fungal protease from Rhizomucor miehei was the most resistant enzyme to the HPH process, showing minimal or no change in proteolytic activity and milk coagulation when processed up to 190 MPa at different concentrations and multiple consecutive processes. However, in the rheological evaluation of milk coagulation using fungal protease homogenized to 190 MPa for up 3 cycles or when homogenized in a solution with a concentration of 20% observed increase in the consistency of the gel. For porcine pepsin, changes on proteolytic activity and milk coagulation were only observed during storage, with reduction of proteolytic activity and an increase on the milk-clotting activity for the enzyme processed at 150 MPa. However, this enzyme promoted a faster coagulation of milk forming more consistent gel immediately after the processing by HPH. During the observation of this gel for 24 hours, this was more compact, firm, less porous and more release of whey of the protein matrix. Overall it was concluded that the highest applied pressures (150 MPa and 190 MPa) positively affected the enzymes with reduced nonspecific proteolytic activity and increased milk-clotting activity, with consequent formation of gels with lower levels of proteolysis, which favors the maintenance of a network of protein rigid, firm and cohesive. Thus, it is concluded that HPH is a promising process that can be applied as a technology to improve the hydrolytic characteristics of milk coagulating enzymes, especially to reduce proteolytic activity and increase the milk-clotting activity. Furthermore, the lower proteolysis in the gel may result in an extension of the shelf life of fresh cheese, by possibly reducing the formation of bitterness flavorMestradoTecnologia de AlimentosMestre em Tecnologia de Alimento

Experimental characterization of a 6.7 GHz coaxial Bragg reflector

A coaxial line periodically loaded by circular disks on the inner conductor is designed and constructed to act as Bragg reflector in the 4.0-9.5 GHz frequency range. This is achieved by placing 10 disks (0.35 cm thick and 6.22 cm in diameter) equally spaced by the periodic distance of 1.8 cm on a coaxial waveguide with inner and outer diameters of 6.90 and 4.22 cm. Experiments on a periodic structure made from stainless steel demonstrate a band gap of 5.6 GHz centered at the 6.7 GHz design frequency in close agreement with 3D microwave computer simulations. © 2007 American Institute of Physics