A teoria da ruína aplicada em um modelo de empresa financeira com risco de crédito

In this work we study a new risk model for a firm which is sensitive to its credit quality, proposed by Yang(2003): Are obtained recursive equations for finite time ruin probability and distribution of ruin time and Volterra type integral equation systems for ultimate ruin probability, severity of ruin and distribution of surplus before and after ruin

Fatores que influenciam a predisposição dos usuários em aderir a uma política de segurança da informação

The information constitutes one of the most valuable strategic assets for the organization. However, the organizational environment in which it is inserted is very complex and heterogeneous, making emerging issues relevant to the Governance of information technology (IT) and Information Security. Academic Studies and market surveys indicate that the origin of most accidents with the information assets is the behavior of people organization itself rather than external attacks. Taking as a basis the promotion of a culture of safety among users and ensuring the protection of information in their properties of confidentiality, integrity and availability, organizations must establish its Information Security Policy (PSI). This policy is to formalise the guidelines in relation to the security of corporate information resources, in order to avoid that the asset vulnerabilities are exploited by threats and can bring negative consequences to the business. But, for the PSI being effective, it is required that the user have readiness to accept and follow the procedures and safety standards. In the light of this context, the present study aims to investigate what are the motivators extrinsic and intrinsic that affect the willingness of the user to be in accordance with the organization's security policies. The theoretical framework addresses issues related to IT Governance, Information Security, Theory of deterrence, Motivation and Behavior Pro-social. It was created a theoretical model based on the studies of Herath and Rao (2009) and D'Arcy, Hovav and Galletta (2009) that are based on General Deterrence Theory and propose the following influencing factors in compliance with the Policy: Severity of Punishment, Certainty of Detection, Peer Behaviour, Normative Beliefs, Perceived Effectiveness and Moral Commitment. The research used a quantitative approach, descriptive. The data were collected through a questionnaire with 18 variables with a Likert scale of five points representing the influencing factors proposed by the theory. The sample was composed of 391 students entering the courses from the Center for Applied Social Sciences of the Universidade Federal do Rio Grande do Norte. For the data analysis, were adopted the techniques of Exploratory Factor Analysis, Analysis of Cluster hierarchical and nonhierarchical, Logistic Regression and Multiple Linear Regression. As main results, it is noteworthy that the factor severity of punishment is what contributes the most to the theoretical model and also influences the division of the sample between users more predisposed and less prone. As practical implication, the research model applied allows organizations to provide users less prone and, with them, to carry out actions of awareness and training directed and write Security Policies more effective.

Avaliação da atividade antimicrobiana das defensinas recombinantes de ervilha (drr230a) e café (cd1) produzidas em Pichia pastoris

The inefficiency of chemical pesticides to control phytopathogenic fungi in agriculture and the frequent incidence of human diseases caused by bacteria which are resistant to antibiotics lead to the search for alternative antimicrobial compounds. In this context, plant defensins are a promising tool for the control of both plant and human pathogenic agents. Plant defensins are cationic peptides of about 50 amino acid residues, rich in cysteine and whose tridimensional structure is considerably conserved among different plant species. These antimicrobial molecules represent an important innate component from plant defense response against pathogens and are expressed in various plant tissues, such as leaves, tubers, flowers, pods and seeds. The present work aimed at the evaluation of the antimicrobial activity of two plant defensins against different phytopathogenic fungi and pathogenic bacteria to humans. The defensin Drr230a, whose gene was isolated from pea (Pisum sativum), and the defensin CD1,whose gene was identified within coffee (Coffea arabica) transcriptome, were subcloned in yeast expression vector and expressed in Pichia pastoris. The gene cd1 was subcloned as two different recombinant forms: CD1tC, containing a six-histidine sequence (6xHis) at the peptide C-terminal region and CD1tN, containing 6xHis coding sequence at the N-terminal region. In the case of the defensin Drr230a, the 6xHis coding sequence was inserted only at the N-terminal region. Assays of the antimicrobial activity of the purified recombinant proteins rDrr230a and rCD1 against Phakopsora pachyrhizi, causal agent of soybean Asian rust, were performed to analyze the in vitro spore germination inhibition and disease severity caused by the fungus in planta. Both recombinant defensins were able to inhibit P. pachyrhizi uredospore germination, with no difference between the antimicrobial action of either CD1tC or CD1tN. Moreover, rDrr230a and rCD1 drastically reduced severity of soybean Asian rust, as demonstrated by in planta assays. In spite of the fact that rCD1 was not able to inhibit proliferation of the human pathogenic bacteria Staplylococcus aureus and Klebsiella pneumoniae, rCD1 was able to inhibit growth of the phytopathogenic fungus Fusarium tucumaniae, that causes soybean sudden death syndrome. The obtained results show that these plant defensins are useful candidates to be used in plant genetic engineering programs to control agriculture impacting fungal diseases.

Toothache and social and economic conditions among adolescents in Northeastern Brazil

O objetivo deste estudo foi relacionar dor de dente com condição socioeconômica, acesso aos serviços de saúde bucal e estilo de vida em adolescentes do município de Sobral, Ceará, desenvolvido com delineamento transversal analítico, com amostra composta por 688 indivíduos. A prevalência de dor de dente no grupo pesquisado foi de 31,8%. Para avaliar a relação entre as variáveis independentes e a dor de dente, realizou-se teste de associação pelo qui-quadrado, estimando-se a razão de prevalências por meio da regressão de Poisson. Os fatores que mais demonstraram relação com a dor de dente foram severidade da cárie, motivo do atendimento odontológico relacionado com urgência, frequência ao dentista e recebimento de escova na escola. Observou-se que a alta prevalência de dor de dente em adolescentes está diretamente relacionada às condições de acesso, assim como às características das ações desenvolvidas pelos serviços de saúde. Assim como há necessidade da implantação de serviços vinculados à promoção de saúde, pautados pela equidade e integralidade, é necessária a implantação de serviços de urgência que não simplesmente intervenham na dor de forma mutiladora, mas a encarem como mecanismo de estímulo ao desenvolvimento de procedimentos de prevenção das doenças bucais.

Síntese de zeólitas e argilas ácidas pilarizadas a partir de matérias primas naturais

Structural changes in waste for zeolites synthesis are subject of many studies carried out in the synthesis of molecular sieves. These materials are named molecular sieves because they have well defined pore sizes and they have the capacity of select molecules by its size. In this work, it was studied the synthesis processes of two types of molecular sieves: pillared acid clays using as starting material one natural montmorillonite clay and the synthesis of zeolites from a silico-aluminous residue. This residue is a byproduct of the extraction of lithium -spodumene. The preparation of pillared acid clays was performed in two steps: 1° acid treatment of clay samples (time and temperature studies) and 2°pilarization of them with Al13 (Keggin ion). The temperature and acid concentration affect the removal of cations in the structure and porosity of the material obtained. The analysis of X-ray diffraction (XRD) and infrared spectroscopy (IR), showed that increasing the severity of the acid treatment compromises the structural material. Also the pore size distribution is approximately uniform. Despite presenting a structural disorganization, the samples were pillared. As evidenced by XRD increasing the basal spacing, specific area and uniform porosity by adsorption of N2. Regarding the microporous molecular sieves were synthesized zeolites A and NaP1 from a silico-aluminous residue, a byproduct of extracting lithium. The temperature and time of agitation during the synthesis were the most important factors for obtaining zeolite A. The aging of the gel and the highest crystallization time promoted the formation of zeolite NaP1 using a Si / Al ratio = 3.2