Predicting Secondary Structures, Contact Numbers, and Residue-wise Contact Orders of Native Protein Structure from Amino Acid Sequence by Critical Random Networks

Prediction of one-dimensional protein structures such as secondary structures and contact numbers is useful for the three-dimensional structure prediction and important for the understanding of sequence-structure relationship. Here we present a new machine-learning method, critical random networks (CRNs), for predicting one-dimensional structures, and apply it, with position-specific scoring matrices, to the prediction of secondary structures (SS), contact numbers (CN), and residue-wise contact orders (RWCO). The present method achieves, on average, $Q_3$ accuracy of 77.8% for SS, correlation coefficients of 0.726 and 0.601 for CN and RWCO, respectively. The accuracy of the SS prediction is comparable to other state-of-the-art methods, and that of the CN prediction is a significant improvement over previous methods. We give a detailed formulation of critical random networks-based prediction scheme, and examine the context-dependence of prediction accuracies. In order to study the nonlinear and multi-body effects, we compare the CRNs-based method with a purely linear method based on position-specific scoring matrices. Although not superior to the CRNs-based method, the surprisingly good accuracy achieved by the linear method highlights the difficulty in extracting structural features of higher order from amino acid sequence beyond that provided by the position-specific scoring matrices.Comment: 20 pages, 1 figure, 5 tables; minor revision; accepted for publication in BIOPHYSIC

Competing for Refugees: A Market-Based Solution to a Humanitarian Crisis

The current refugee crisis demands novel legal solutions, and new ways of summoning the political will to implement them. As a matter of national incentives, the goal must be to design mechanisms that discourage countries of origin from creating refugees, and encourage host countries to welcome them. One way to achieve this would be to recognize that persecuted refugee groups have a financial claim against their countries of origin, and that this claim can be traded to host nations in exchange for acceptance. Modifications to the international apparatus would be necessary, but the basic legal elements of this proposal already exist. In short, international law can and should give refugees a legal asset, give host nations incentives to accept them, and give oppressive countries of origin the bill

Chaos in cosmological Hamiltonians

This paper summarises a numerical investigation which aimed to identify and characterise regular and chaotic behaviour in time-dependent Hamiltonians H(r,p,t) = p^2/2 + U(r,t), with U=R(t)V(r) or U=V[R(t)r], where V(r) is a polynomial in x, y, and/or z, and R = const * t^p is a time-dependent scale factor. When p is not too negative, one can distinguish between regular and chaotic behaviour by determining whether an orbit segment exhibits a sensitive dependence on initial conditions. However, chaotic segments in these potentials differ from chaotic segments in time-independent potentials in that a small initial perturbation will usually exhibit a sub- or super-exponential growth in time. Although not periodic, regular segments typically exhibit simpler shapes, topologies, and Fourier spectra than do chaotic segments. This distinction between regular and chaotic behaviour is not absolute since a single orbit segment can seemingly change from regular to chaotic and visa versa. All these observed phenomena can be understood in terms of a simple theoretical model.Comment: 16 pages LaTeX, including 5 figures, no macros require

Stellar Oscillons

We study the weakly nonlinear evolution of acoustic instability of a plane- parallel polytrope with thermal dissipation in the form of Newton's law of cooling. The most unstable horizontal wavenumbers form a band around zero and this permits the development of a nonlinear pattern theory leading to a complex Ginzburg-Landau equation (CGLE). Numerical solutions for a subcritical, quintic CGLE produce vertically oscillating, localized structures that resemble the oscillons observed in recent experiments of vibrated granular material.Comment: 12 Latex pages using aasms4.sty, 2 postscript figures, submitted to the proceedings of the Florida Workshop in Nonlinear Astrophysics and Physic

Thirty Years After Michael E. Porter: What Do We Know About Business Exit?

Although a business exit is an important corporate change initiative, the buyer’s side seems to be more appealing to management researchers than the seller’s because acquisitions imply growth, i.e., success. Yet from an optimistic viewpoint, business exit can effectively create value for the selling company. In this paper we attempt to bring the relevance of the seller’s side back into our consciousness by asking: What do we know about business exit? We start our exploration with Porter (1976), focusing on literature that investigates the antecedents of, barriers to, and outcomes of business exit. We also include studies from related fields such as finance and economics.1 Through this research we determine three clusters of findings: factors promoting business exit, exit barriers, and exit outcomes. Overall, it is the intention of this paper to highlight the importance of business exit for research and practice. Knowing what we know about business exits and their high financial value we should bear in mind that exit need not mean failure but a new beginning for a corporation

Comparing the performance of the SF-6D and the EQ-5D in different patient groups

Introduction: This research aims to explore the performance of the SF-6D and the EQ-5D in patients suffering from asthma, chronic obstructive pulmonary disease, cataracts, and rheumatoid arthritis. In particular, the aim of this research is twofold: 1) to study the level of agreement between the indexes and the descriptive systems of the dimensions of the SF-6D and the EQ-5D, and 2) to analyze the discriminative ability of the instruments. Material and Methods: A sample of 643 patients completed both the SF-36v2 and the EQ-5D. The discriminative ability of the instruments was analyzed. Furthermore, the level of agreement between the indexes and the descriptive systems of the dimensions of the SF-6D and the EQ-5D were studied. The level of agreement between instruments was investigated using correlation coefficients and the Bland-Altman plots, while the influence of medical condition and other socio-demographic variables was analyzed using non-parametric tests. Paired-samples tests were used to identify differences between the scores. Results and Discussion: The results show a strong correlation and agreement between both indexes. Overall, questionnaire indexes differ by medical condition and socio-demographic groups and both instruments are able to discriminate between socio-demographic groups. Conclusion: This study confirmed the hypothesis that the SF-6D generates higher utility values in less healthy individuals. The SF-6D and the EQ-5D seem to perform differently in each of the diseases studied since the descriptive statistics differ between instruments and the level of correlation is not uniform. Results show that the instruments generate different utility values, but there is a strong agreement between both indexes. Thus, the two instruments are not interchangeable and their results cannot be directly comparable.Portuguese Foundation for Science and Technology (Fundacao para a Ciencia e a Tecnologia)info:eu-repo/semantics/publishedVersio

Pneumocéfalo Espontâneo Hipertensivo

info:eu-repo/semantics/publishedVersio

Medical curricula on intimate partner violence in Mozambique

Introduction: The aim of the study described in this paper is to screen medical curricula in relation to the attention paid to intimate partner violence, by applying a framework derived from the international literature. Material and Methods: We screened curricula of five Mozambican medical schools based on a state-of-the-art intimate partner violence curriculum framework. The latter framework was based on a review of the literature. Results: Few medical schools of Mozambique could be identified addressing intimate partner violence in their curriculum. When tackled, intimate partner violence content is mostly dealt within the context of Obstetrics and Gynaecology, Community Health and Forensic Medicine rotations. Intimate partner violence contents are integrated as stand-alone modules in some specific subjects. In none of the schools, specific teachers teaching intimate partner violence could be identified. No time allocation was specified to address the topic; no teaching and learning strategies could be identified invoking awareness or supporting basic knowledge acquisition; additionally, hardly any information about related assessment methods was found. Only in one medical school was the subject part of the formal curriculum. Discussion: Intimate partner violence content is hardly and inconsistently addressed. The limited intimate partner violence content tracked in the Mozambican medical schools’ curricula, mainly addresses violence in general, for instance as identified in Orthopaedics or Surgery contexts and sexual violence in Obstetrics and Gynaecology. The inclusion of elements of intimate partner violence in the curriculum remains restricted, questioning the impact of medical education of future practitioners’ competencies. Conclusion: Critical changes are needed in medical curricula to match the current epidemiology of intimate partner violence in Mozambique

A Violência no Local de Trabalho em Instituições de Saúde: Um Estudo Monocêntrico sobre Causas, Consequências e Estratégias de Prevenção

Introduction: Workplace violence is one of the main risk factors in the professional world. Healthcare workers are at higher risk when compared to other sectors. Our study aimed to characterize physical and verbal violence in a public hospital and to define occupational health prevention and surveillance strategies. Material and Methods: Single center observational cross-sectional study, carried amongst healthcare workers in a public hospital in Lisbon. A qualitative survey was carried out through six in-depth interviews. A quantitative survey was carried through questionnaires delivered to 32 workers. A significance level of 5% was accepted in the assessment of statistical differences. The Mann-Whitney test and the Fisher’s exact test were used to calculate p values. Results: The main results are: (1) 41 violence incidents were reported in the quantitative phase; (2) 5/21 [23.81%] victims notified the incident to the occupational health department; (3) 18/21 [85.71%] victims reported a permanent state of hypervigilance; (4) 22/28 [78.57%] participants self-reported poor or no familiarity with internal reporting procedures; (5) 24/28 [85.71%] participants believed it is possible to minimize workplace violence. Discussion: Workplace violence is favored by unrestricted access to working areas, absence of security guards and police officers or scarce intervention. The low notification rate contributes to organizational lack of action. The state of hypervigilance reported in our study reflects the negative effects of threatening occupational stressors on mental health. Conclusion: Our results show that workplace violence is a relevant risk factor that significantly impacts workers’ health in a noxious manner, deserving a tailored occupational health approach whose priority areas and strategies have been determined.Introdução: A violência no local de trabalho é um dos principais fatores de risco no mundo do trabalho. Os trabalhadores da saúde apresentam um risco superior. O nosso estudo teve como objetivo caracterizar a violência física e verbal num hospital público e definir estratégias de prevenção e vigilância em saúde ocupacional. Material e Métodos: Estudo observacional transversal monocêntrico, conduzido num hospital público em Lisboa com trabalhadores da saúde. Foi realizado um inquérito qualitativo com entrevistas em profundidade a seis trabalhadores e um inquérito quantitativo com questionários a 32 trabalhadores. Aceitou-se um nível de significância de 5% na avaliação das diferenças estatísticas. O teste de Mann-Whitney e o teste exato de Fisher foram usados para calcular os valores de p. Resultados: Os principais resultados são: (1) 41 episódios reportados na fase quantitativa; (2) 5/21 [23,81%] vítimas notificaram o incidente; (3) 18/21 [85.71%] vítimas reportaram estados de hipervigilância permanente; (4) 22/28 [78,57%] participantes não conheciam ou conheciam mal os procedimentos de notificação; (5) 24/28 [85,71%] consideravam possível minimizar o problema. Discussão: A violência é favorecida pelo acesso livre às zonas de trabalho, ausência de agentes de segurança e polícia ou falta da respetiva intervenção. A baixa notificação contribui para a ausência de medidas organizacionais. O estado de hipervigilância relatado reflete o efeito prejudicial da exposição a fontes de stress e ameaça. Conclusão: A violência no local de trabalho é um fator de risco relevante, com impacto negativo na saúde dos trabalhadores e merece uma abordagem individualizada no âmbito da saúde ocupacional, cujas áreas e estratégias prioritárias foram definidas neste estudo. Palavras-chave: Fatores de Risco Profissionais; Prevenção; Saúde Ocupacional; Trabalhadores da Saúde; Violência no Local de trabalho.info:eu-repo/semantics/publishedVersio

Nutrition education in portuguese medical students: impact on the attitudes and knowledge

Nutrition has been underrepresented in the curriculum of many medical schools and therefore physicians do not feel adequately prepared to provide dietary counselling. The aim of the present study is to determine the impact of a Nutrition and Metabolism curricular unit on nutrition attitudes, knowledge and confidence on future clinical practice of medical students.info:eu-repo/semantics/publishedVersio