An audiovisual material for the teaching of the statistics. 'Un material audiovisual didáctico para la enseñanza de la estadística'.

Resumen basado en el de la publicación

Sample size planning for multiple correlation : reply to Shieh (2013)

Resumen tomado de la publicaci??n

The mapping of the local contributions of Fermi and Coulomb correlation into intracule and extracule density distributions

The contributions of the correlated and uncorrelated components of the electron-pair density to atomic and molecular intracule I(r) and extracule E(R) densities and its Laplacian functions ∇2I(r) and ∇2E(R) are analyzed at the Hartree-Fock (HF) and configuration interaction (CI) levels of theory. The topologies of the uncorrelated components of these functions can be rationalized in terms of the corresponding one-electron densities. In contrast, by analyzing the correlated components of I(r) and E(R), namely, IC(r) and EC(R), the effect of electron Fermi and Coulomb correlation can be assessed at the HF and CI levels of theory. Moreover, the contribution of Coulomb correlation can be isolated by means of difference maps between IC(r) and EC(R) distributions calculated at the two levels of theory. As application examples, the He, Ne, and Ar atomic series, the C2-2, N2, O2+2 molecular series, and the C2H4 molecule have been investigated. For these atoms and molecules, it is found that Fermi correlation accounts for the main characteristics of IC(r) and EC(R), with Coulomb correlation increasing slightly the locality of these functions at the CI level of theory. Furthermore, IC(r), EC(R), and the associated Laplacian functions, reveal the short-ranged nature and high isotropy of Fermi and Coulomb correlation in atoms and molecules

Systematic study of the static electrical properties of the CO molecule: influence of the basis set size and correlation energy

The influence of the basis set size and the correlation energy in the static electrical properties of the CO molecule is assessed. In particular, we have studied both the nuclear relaxation and the vibrational contributions to the static molecular electrical properties, the vibrational Stark effect (VSE) and the vibrational intensity effect (VIE). From a mathematical point of view, when a static and uniform electric field is applied to a molecule, the energy of this system can be expressed in terms of a double power series with respect to the bond length and to the field strength. From the power series expansion of the potential energy, field-dependent expressions for the equilibrium geometry, for the potential energy and for the force constant are obtained. The nuclear relaxation and vibrational contributions to the molecular electrical properties are analyzed in terms of the derivatives of the electronic molecular properties. In general, the results presented show that accurate inclusion of the correlation energy and large basis sets are needed to calculate the molecular electrical properties and their derivatives with respect to either nuclear displacements or/and field strength. With respect to experimental data, the calculated power series coefficients are overestimated by the SCF, CISD, and QCISD methods. On the contrary, perturbation methods (MP2 and MP4) tend to underestimate them. In average and using the 6-311 + G(3df) basis set and for the CO molecule, the nuclear relaxation and the vibrational contributions to the molecular electrical properties amount to 11.7%, 3.3%, and 69.7% of the purely electronic μ, α, and β values, respectively

Variational calculation of vibrational linear and nonlinear optical properties

A variational approach for reliably calculating vibrational linear and nonlinear optical properties of molecules with large electrical and/or mechanical anharmonicity is introduced. This approach utilizes a self-consistent solution of the vibrational Schrödinger equation for the complete field-dependent potential-energy surface and, then, adds higher-level vibrational correlation corrections as desired. An initial application is made to static properties for three molecules of widely varying anharmonicity using the lowest-level vibrational correlation treatment (i.e., vibrational Møller-Plesset perturbation theory). Our results indicate when the conventional Bishop-Kirtman perturbation method can be expected to break down and when high-level vibrational correlation methods are likely to be required. Future improvements and extensions are discussed

Basis set and electron correlation effects on initial convergence for vibrational nonlinear optical properties of conjugated organic molecules

The level of ab initio theory which is necessary to compute reliable values for the static and dynamic (hyper)polarizabilities of three medium size π-conjugated organic nonlinear optical (NLO) molecules is investigated. With the employment of field-induced coordinates in combination with a finite field procedure, the calculations were made possible. It is stated that to obtain reasonable values for the various individual contributions to the (hyper)polarizability, it is necessary to include electron correlation. Based on the results, the convergence of the usual perturbation treatment for vibrational anharmonicity was examined

Incongruence between test statistics and P values in medical papers

Given an observed test statistic and its degrees of freedom, one may compute the observed P value with most statistical packages. It is unknown to what extent test statistics and P values are congruent in published medical papers. Methods: We checked the congruence of statistical results reported in all the papers of volumes 409–412 of Nature (2001) and a random sample of 63 results from volumes 322–323 of BMJ (2001). We also tested whether the frequencies of the last digit of a sample of 610 test statistics deviated from a uniform distribution (i.e., equally probable digits).Results: 11.6% (21 of 181) and 11.1% (7 of 63) of the statistical results published in Nature and BMJ respectively during 2001 were incongruent, probably mostly due to rounding, transcription, or type-setting errors. At least one such error appeared in 38% and 25% of the papers of Nature and BMJ, respectively. In 12% of the cases, the significance level might change one or more orders of magnitude. The frequencies of the last digit of statistics deviated from the uniform distribution and suggested digit preference in rounding and reporting.Conclusions: this incongruence of test statistics and P values is another example that statistical practice is generally poor, even in the most renowned scientific journals, and that quality of papers should be more controlled and valued

Indicadores da individualização de cuidados para o curso de licenciatura em enfermagem

RESUMO: A individualização dos cuidados de enfermagem tem sido associada a uma evolução clínica mais favorável, representando um importante parâmetro de avaliação e de desenvolvimento dos serviços de saúde. A tónica atribuída a esta problemática não só é evidenciada por diversos autores, como se enquadra nas metas de modernização do Sistema Nacional de Saúde e é destaque em vários códigos normativos da profissão nacionais e internacionais, como uma obrigação moral e deontológica. Assim, pretende-se mediante os ganhos em saúde sensíveis às intervenções de enfermagem, identificar quais indicadores do cuidado individualizado, para se efectivar a sua incorporação na formação inicial em enfermagem. Para tal efeito, construiu-se uma bateria de indicadores mediante análise de duas revisões sistemáticas da literatura, que teve por base o Modelo da Eficácia do Papel de Enfermagem, desenvolvido por Irvine et al. (1998). Para à adaptação à realidade portuguesa recorreu-se à técnica de Delphi, com duas rondas, que incluiu respectivamente, 12 e 10 peritos de enfermagem. Na análise de dados utilizou-se o nível de concordância superior ou igual a 90%, na última ronda. Na segunda fase do estudo, aplicou-se um inquérito por questionário (α de Cronbach = 0,919) para testar a sua aplicabilidade dos indicadores, a 156 enfermeiros, do mesmo hospital da área da grande Lisboa, no Serviço de Medicina e Cirurgia. Recorreu-se ao SPSS, versão 19 e realizou-se análise univariada e estatística analítica. Na bateria final de indicadores foram incorporados aqueles com ponderação positiva (≥51%). Os dados qualitativos obtidos foram submetidos a análise de conteúdo. Dos 58 indicadores iniciais, consolidaram-se 8 categorias: cuidado à pessoa em fim de vida e família, toque terapêutico, educação para a auto-gestão da saúde, cuidados de proximidade, gestão de casos, empoderamento/ literacia para a saúde, linha telefónica de apoio permanente/ tele-assistência e apoio psico-emocional, com valorização de 28 indicadores. O tempo de experiência profissional, tipo de serviço e tempo de permanência no mesmo serviço influenciou a percepção dos enfermeiros, confirmando os pressupostos de Irvine et al. (1998) e Benner (2001). A correlação total dos indicadores, no questionário, variou entre 0,248 e 0,650, para p<0,01. O facto de todas as correlações serem positivas significa que provavelmente estão associados à problemática da individualização, pelo que se sugere a sua transposição para o ensino de enfermagem. ABSTRACT: The individualization of nursing care has been associated with a more favorable clinical evolution, an important parameter for the evaluation and development of health services. The emphasis given to this problem is not only evidenced by several authors, as fits the goals of modernizing the National Health System and is featured in several normative codes of the profession nationally and internationally, as a moral and ethical obligation. Thus, it is intended by the gains in health sensitive to nursing interventions, identify indicators of individualized care and give effect to its incorporation into the initial training in nursing. For this purpose, we constructed a series of indicators by analyzing two systematic reviews of literature, which was based on the The Nursing Role Effectiveness Model developed by Irvine et al. (1998). For the adaptation to the Portuguese appealed to the Delphi technique with two rounds, which included, respectively, 10 and 12 nursing experts. In data analysis we used the level of agreement greater than or equal to 90% in the last round. In the second phase of the study, we applied a questionnaire (Cronbach's α = 0.919) to test the applicability of the indicators, the 156 nurses in the same hospital in the Greater Lisbon area, the Department of Medicine and Surgery. Done using the SPSS, version 19 and conducted a univariate analysis and analytical statistics. In the final heat of indicators were incorporated into those with positive weight (≥ 51%). Qualitative data were subjected to content analysis. Of the initial 58 indicators, eight were consolidated categories: care to the person and family life, therapeutic touch education for self-management of health care outreach, case management, empowerment / literacy to health, a telephone line permanent support / tele-assistance and psycho-emotional, with an appreciation of 28 indicators. The length of professional experience, type of service and length of stay in the same service influenced the perception of nurses, confirming the assumptions of Irvine et al. (1998) and Benner (2001). The total correlation of the indicators in the questionnaire ranged between 0.248 and 0.650, p <0.01. The fact that all correlations are positive means that are probably associated with the problem of individuation, which is suggested by its implementation in nursing education.

Relação dos centros de pressão dos quatro apoios do cavalo com a conformação dos respetivos membros

A conformação pode modular a predisposição para lesões de um cavalo. Por outro lado, o comportamento dos centros de pressão (CdP) dos cascos do cavalo pode fornecer informação relativa ao desempenho mecânico do seu sistema biológico. O objetivo deste trabalho foi testar a correlação dos CdP dos cascos com os principais defeitos de conformação da população estudada. Oito cavalos Puro Sangue Lusitano (PSL) saudáveis, com a cabeça numa posição neutra foram colocados, durante 15 ensaios de 8 segundos, com os membros anteriores (MA) numa placa de pressão e com os membros posteriores (MP) noutra. Os resultados sincronizados foram usados para caracterizar o deslocamento do CdP de cada casco e estudar a sua correlação com a conformação. Os resultados foram analisados de forma qualitativa, através da interpretação de áreas de contato e estabilogramas, assim como de forma quantitativa utilizando estatística inferencial para determinar uma eventual correlação com a conformação, recorrendo a um índice de conformação (IC). O defeito de conformação mais frequente foi os cavalos serem “esquerdos” e o que menos se observou foi serem “fechados de frente”. O IC variou entre 1 e 7. A média das áreas de contato dos cascos dos 8 cavalos foi maior nos MP do que nos MA, tendo acontecido o mesmo para os valores dos deslocamentos do CdP, que foram significativamente maiores nos MP do que nos MA Não foi detetada correlação entre os deslocamentos totais dos CdP e a conformação. Concluíu-se que o CdP dos PSL em estação não está dependente de variações de conformação em que o IC seja igual ou inferior a 7.

Correlation of the articulation index to the MTS test under different listening conditions

This paper reviews a study to determine the relation between the aided articulation index and the aided speech recognition scores obtained with the Monosyllable, Trochee and Spondee (MTS) Test, when administered to hearing-impaired children.