2 resultados para DETERRENCE

em Universidade Federal do Rio Grande do Norte(UFRN)


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Dengue fever, currently the most important arbovirus, is transmitted by the bite of the Aedes aegypti mosquito. Given the absence of a prophylactic vaccine, the disease can only be controlled by combating the vector insect. However, increasing reports of resistance and environmental damage caused by insecticides have led to the urgent search for new safer alternatives. Twenty - um plant s eed extracts from the Caatinga were prepared , tested and characterized . Sodium phosphate ( 50 mM pH 8.0) was used as extractor. All extracts showed larvicidal and ovipositional deterrence activity . Extracts of D. grandiflora, E. contortisiliquum, A. cearenses , C. ferrea and C. retusa were able to attract females for posture when in low co ncentration . In the attractive concentrations, the CE of E. contortisiliquum and A. cearenses were able to kill 52% and 100% of the larvae respectively . The extracts of A. cearenses , P. viridiflora, E. velutina, M. urundeuva and S. brasiliensis were also pupicides, while extracts of P. viridiflora, E. velutina, E. contortisiliquum , A. cearenses, A. colubrina, D. grandiflora , B. cheilantha , S. spectabilis, C. pyramidalis, M. regnelli e G. americana displayed adulticidal activity. All extracts were toxic to C. dubia zooplankton . The EB of E. velutina and E. contortisiliquum did not affect the viability of fibroblasts . In all extracts were identified at least two potential insecticidal proteins such as enzyme inhibitors, lectins and chitin - binding proteins and components of secondary metabolism . Considering all bioassays , the extracts from A. cearenses, P. viridiflora, E. contortisiliquum , S. brasiliensis, E. velutina and M. urundeuva were considered the most promising . The E. contortisiliquum extracts was the only one who did not show pupicida activity, indicating that its mechanism of action larvicide and adulticidal is related only to the ingesti on of toxic compounds by insect , so it was selected to be fragmenting. As observed for the CE , th e protein fractions of E. contortisiliquum also showed larvicidal activity, highlighting that F2 showed higher larvicidal activity and lower en vironmental toxicity than the CE source. The reduction in the proteolytic activity of larvae fed with crude extra ct and fractions of E. contortisiliquum suggest ed that the trypsin inhibitors ( ITEc) would be resp onsible for larvicidal activity . However the increase in the purification of this inhibitor resulted in loss of larvicidal activity , but the absence of trypsin inhibitor reduced the effectiveness of the fractions , indicating that the ITEC contributes to the larvicidal activity of this extract. Not been observed larvicidal activity and adulticide in rich fraction vicilin, nor evidence of the contribution o f this molecule for the larvicidal activity of the extract. The results show the potential of seeds from plant extracts of Caatinga as a source of active molecules against insects A. aegypti at different stages of its development cycle, since they are comp osed of different active compounds, including protein nature, which act on different mechanisms should result in the death of insec

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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.