Multiple imputation for body mass index: lessons from the Australian Longitudinal Study on Women's Health

In large epidemiological studies missing data can be a problem, especially if information is sought on a sensitive topic or when a composite measure is calculated from several variables each affected by missing values. Multiple imputation is the method of choice for 'filling in' missing data based on associations among variables. Using an example about body mass index from the Australian Longitudinal Study on Women's Health, we identify a subset of variables that are particularly useful for imputing values for the target variables. Then we illustrate two uses of multiple imputation. The first is to examine and correct for bias when data are not missing completely at random. The second is to impute missing values for an important covariate; in this case omission from the imputation process of variables to be used in the analysis may introduce bias. We conclude with several recommendations for handling issues of missing data. Copyright (C) 2004 John Wiley Sons, Ltd.

The epidemiology of dysphagia: Describing the problem - are we too late?

The assessment and management of dysphagia is a rapidly growing part of speech pathology clinical practice for both adult and paediatric populations, yet there is limited information available regarding the epidemiology of dysphagia. Very few studies have defined the characteristics of the disorder, its incidence/prevalence in various populations, the natural history of the disorder or the relative risks, comorbidities and outcomes associated with dysphagia. The current paper will identify some fundamental questions that as yet remain unanswered and highlight areas of future research that are required in order for us to have a better understanding of dysphagia and inform assessment and management. In conclusion, the authors propose an epidemiological framework and highlight information needs in the field of dysphagia. This framework urges future dysphagia research to be informed and underpinned by sound epidemiological principles.

Body-mass management of Australian lightweight rowers prior to and during competition

Purpose: Although the body-mass management strategies of athletes in high-participation weight-category sports such as wrestling have been thoroughly investigated, little is known about such practices among lightweight rowers. This study examined the body-mass management practices of lightweight rowers before competition and compared these with current guidelines of the International Federation of Rowing Association (FISA). Quantification of nutrient intake in the 1-2 h between weigh-in and racing was also sought. Methods: Lightweight rowers (N = 100) competing in a national regatta completed a questionnaire that assessed body-mass management practices during the 4 wk before and throughout a regatta plus recovery strategies after weigh-in. Biochemical data were collected immediately after weigh-in to validate questionnaire responses. Responses were categorized according to gender and age category (Senior B or younger than 23 yr old, i.e., U23, Senior A or OPEN, i.e., open age limit) for competition. Results: Most athletes (male U23 76.5%, OPEN 92.3%; female U23 84.0%, OPEN 94.1%) decreased their body mass in the weeks before the regatta at rates compliant with FISA guidelines. Gradual dieting, fluid restriction, and increased training load were the most popular methods of body-mass management. Although the importance of recovery after weigh-in was recognized by athletes, nutrient intake and especially sodium (male U23 5.3 ± 4.9, OPEN 7.7 ± 5.9; female U23 5.7 ± 6.8, OPEN 10.2 ± 5.4 mg-kg(-1)) and fluid intake (male U23 12.1 ± 7.1, OPEN 13.5 ± 8.1; female U23 9.4 ± 7.4, OPEN 14.8 ± 6.9 mL.kg(-1)) were below current sports nutrition recommendations. Conclusion: Few rowers were natural lightweights; the majority reduced their body mass in the weeks before a regatta. Nutritional recovery strategies implemented by lightweight rowers after weigh-in were not consistent with current guidelines.

A First Order Predicate Logic Formulation of the 3D Reconstruction Problem and its Solution Space

This paper defines the 3D reconstruction problem as the process of reconstructing a 3D scene from numerous 2D visual images of that scene. It is well known that this problem is ill-posed, and numerous constraints and assumptions are used in 3D reconstruction algorithms in order to reduce the solution space. Unfortunately, most constraints only work in a certain range of situations and often constraints are built into the most fundamental methods (e.g. Area Based Matching assumes that all the pixels in the window belong to the same object). This paper presents a novel formulation of the 3D reconstruction problem, using a voxel framework and first order logic equations, which does not contain any additional constraints or assumptions. Solving this formulation for a set of input images gives all the possible solutions for that set, rather than picking a solution that is deemed most likely. Using this formulation, this paper studies the problem of uniqueness in 3D reconstruction and how the solution space changes for different configurations of input images. It is found that it is not possible to guarantee a unique solution, no matter how many images are taken of the scene, their orientation or even how much color variation is in the scene itself. Results of using the formulation to reconstruct a few small voxel spaces are also presented. They show that the number of solutions is extremely large for even very small voxel spaces (5 x 5 voxel space gives 10 to 10(7) solutions). This shows the need for constraints to reduce the solution space to a reasonable size. Finally, it is noted that because of the discrete nature of the formulation, the solution space size can be easily calculated, making the formulation a useful tool to numerically evaluate the usefulness of any constraints that are added.

The problem of appraising qualitative research

Qualitative research can make a valuable contribution to the study of quality and safety in health care. Sound ways of appraising qualitative research are needed, but currently there are many different proposals with few signs of an emerging consensus. One problem has been the tendency to treat qualitative research as a unified field. We distinguish universal features of quality from those specific to methodology and offer a set of minimally prescriptive prompts to assist with the assessment of generic features of qualitative research. In using these, account will need to be taken of the particular method of data collection and methodological approach being used. There may be a need for appraisal criteria suited to the different methods of qualitative data collection and to different methodological approaches. These more specific criteria would help to distinguish fatal flaws from more minor errors in the design, conduct, and reporting of qualitative research. There will be difficulties in doing this because some aspects of qualitative research, particularly those relating to quality of insight and interpretation, will remain difficult to appraise and will rely largely on subjective judgement.

Application of ensemble averaging to the analysis of electromyography recordings under whole body vibratory stimulation

The aim of this study is to evaluate the application of ensemble averaging to the analysis of electromyography recordings under whole body vibratory stimulation. Recordings from Rectus Femoris, collected during vibratory stimulation at different frequencies, are used. Each signal is subdivided in intervals, which time duration is related to the vibration frequency. Finally the average of the segmented intervals is performed. By using this method for the majority of the recordings the periodic components emerge. The autocorrelation of few seconds of signals confirms the presence of a pseudosinusoidal components strictly related to the soft tissues oscillations caused by the mechanical waves. © 2014 IEEE.

Investigating the role of capacitive coupling between the operating table and the return electrode of an electrosurgery unit in the modification of the current density distribution within the patients’ body

Background: Electrosurgery units are widely employed in modern surgery. Advances in technology have enhanced the safety of these devices, nevertheless, accidental burns are still regularly reported. This study focuses on possible causes of sacral burns as complication of the use of electrosurgery. Burns are caused by local densifications of the current, but the actual pathway of current within patient's body is unknown. Numerical electromagnetic analysis can help in understanding the issue. Methods: To this aim, an accurate heterogeneous model of human body (including seventy-seven different tissues), electrosurgery electrodes, operating table and mattress was build to resemble a typical surgery condition. The patient lays supine on the mattress with the active electrode placed onto the thorax and the return electrode on his back. Common operating frequencies of electrosurgery units were considered. Finite Difference Time Domain electromagnetic analysis was carried out to compute the spatial distribution of current density within the patient's body. A differential analysis by changing the electrical properties of the operating table from a conductor to an insulator was also performed. Results: Results revealed that distributed capacitive coupling between patient body and the conductive operating table offers an alternative path to the electrosurgery current. The patient's anatomy, the positioning and the different electromagnetic properties of tissues promote a densification of the current at the head and sacral region. In particular, high values of current density were located behind the sacral bone and beneath the skin. This did not occur in the case of non-conductive operating table. Conclusion: Results of the simulation highlight the role played from capacitive couplings between the return electrode and the conductive operating table. The concentration of current density may result in an undesired rise in temperature, originating burns in body region far from the electrodes. This outcome is concordant with the type of surgery-related sacral burns reported in literature. Such burns cannot be immediately detected after surgery, but appear later and can be confused with bedsores. In addition, the dosimetric analysis suggests that reducing the capacity coupling between the return electrode and the operating table can decrease or avoid this problem. © 2013 Bifulco et al.; licensee BioMed Central Ltd.

Toward Prevention of Childhood Sexual Abuse: Preschoolers’ Knowledge of Genital Body Parts

This study examined preschool children’s knowledge of their genital and non-genital body parts. Results indicated that almost all preschool children knew the correct terms for their non-genital body parts, but few knew the correct terminology for their genitals. The importance of this skill in preventing childhood sexual abuse is discussed.

Participation in a positive youth development program and multi -problem alternative high school students' transformative goals: An investigation of the theoretical and methodological utility and validity of the Transformative Goal Attainment (TGAS)

There is a growing body of literature that provides evidence for the efficacy of positive youth development programs in general and preliminary empirical support for the efficacy of the Changing Lives Program (CLP) in particular. This dissertation sought to extend previous efforts to develop and preliminarily examine the Transformative Goal Attainment Scale (TGAS) as a measure of participant empowerment in the promotion of positive development. Consistent with recent advances in the use of qualitative research methods, this dissertation sought to further investigate the utility of Relational Data Analysis (RDA) for providing categorizations of qualitative open-ended response data. In particular, a qualitative index of Transformative Goals, TG, was developed to complement the previously developed quantitative index of Transformative Goal Attainment (TGA), and RDA procedures for calculating reliability and content validity were refined. Second, as a Stage I pilot/feasibility study this study preliminarily examined the potentially mediating role of empowerment, as indexed by the TGAS, in the promotion of positive development. ^ Fifty-seven participants took part in this study, forty CLP intervention participants and seventeen control condition participants. All 57 participants were administered the study's measures just prior to and just following the fall 2003 semester. This study thus used a short-term longitudinal quasi-experimental research design with a comparison control group. ^ RDA procedures were refined and applied to the categorization of open-ended response data regarding participants' transformative goals (TG) and future possible selves (PSQ-QE). These analyses revealed relatively strong, indirect evidence for the construct validity of the categories as well as their theoretically meaningful structural organization, thereby providing sufficient support for the utility of RDA procedures in the categorization of qualitative open-ended response data. ^ In addition, transformative goals (TG) and future possible selves (PSQ-QE), and the quantitative index of perceived goal attainment (TGA) were evaluated as potential mediators of positive development by testing their relationships to other indices of positive intervention outcome within a four-step method involving both analysis of variance (ANOVA and RMANOVAs) and regression analysis. Though more limited in scope than the efforts at the development and refinement of the measures of these mediators, the results were also promising. ^

Metáforas del amor en la poesía de la Grecia antigua (I): la épica y la lírica arcaicas

Partiendo del concepto de metáfora cognitiva, que complementa al más conocido de metáfora literaria, y analizando la base conceptual que a ambas subyace, pretendemos un cuidadoso análisis de los textos de poesía épica y lírica arcaicas, sin olvidar la importancia fundamental del contexto cultural en que estos surgen, para obtener una mejor comprensión de la forma en que los griegos conceptualizaban el sentimiento amoroso.

A Survey on Mobile Anchor Node Assisted Localization in Wireless Sensor Networks

Localization is one of the key technologies in Wireless Sensor Networks (WSNs), since it provides fundamental support for many location-aware protocols and applications. Constraints on cost and power consumption make it infeasible to equip each sensor node in the network with a Global Position System (GPS) unit, especially for large-scale WSNs. A promising method to localize unknown nodes is to use mobile anchor nodes (MANs), which are equipped with GPS units moving among unknown nodes and periodically broadcasting their current locations to help nearby unknown nodes with localization. A considerable body of research has addressed the Mobile Anchor Node Assisted Localization (MANAL) problem. However to the best of our knowledge, no updated surveys on MAAL reflecting recent advances in the field have been presented in the past few years. This survey presents a review of the most successful MANAL algorithms, focusing on the achievements made in the past decade, and aims to become a starting point for researchers who are initiating their endeavors in MANAL research field. In addition, we seek to present a comprehensive review of the recent breakthroughs in the field, providing links to the most interesting and successful advances in this research field.

Autocriticismo, Estima Corporal e Sintomas de Perturbação do Comportamento Alimentar em Adolescentes do Sexo Feminino, Praticantes de Ballet e Andebol

Introdução: As Perturbações do Comportamento Alimentar (PCA) constituem um grave problema de saúde pública. Poucos estudos em Portugal ligam esta temática a áreas como o autocriticismo e a estima corporal. Assim, são nossos objetivos principais: explorar, numa amostra de adolescentes do sexo feminino, as diferenças entre praticantes de ballet e praticantes de andebol, nos sintomas de PCA, índice de massa corporal (IMC), dimensões avaliativas da aparência e níveis de autocriticismo; analisar se níveis maiores de autocriticismo e uma visão mais depreciativa em termos de aparência se associam a níveis mais elevados de sintomas de PCA (nas duas modalidades desportivas). Em virtude das associações encontradas, pretendemos realizar análises preditivas, controlando a influência de sintomas de depressão, ansiedade e stress. Metodologia: A amostra é constituída por 105 adolescentes do sexo feminino (n = 52; 49,5% do ballet e n = 53; 50,5% do andebol) com idades compreendidas entre os 12 e 18 anos (M = 14,5; DP = 1,80). As participantes preencheram um protocolo composto por um questionário sociodemográfico, pela Escala de Autocriticismo e Autotranquilização (FSCRS), pelo Teste de Atitudes Alimentares-25 (TAA-25/EAT-25), pela Escala Estima Corporal (BES) e pela Escala Depressão Ansiedade e Stress (DASS-21). Resultados: Verificaram-se percentagens preocupantes de eventual PCA (ponto de corte de 19) nas praticantes de Ballet (7,7%) e de Andebol (9,4%). Quanto ao IMC, na amostra de praticantes de ballet, encontrou-se uma percentagem relevante de jovens com magreza (34,6%). As praticantes de Ballet e de Andebol apenas se diferenciaram no IMC e na dimensão FSCRS_eu inadequado (valores superiores nas praticantes de Andebol). Verificaram-se, na subamostra Ballet, associações significativas entre a Motivação para a Magreza e as formas de autocriticismo FSCRS_eu inadequado, FSCRS_eu detestado, FSCRS_eu tranquilizador e FSCRS_total e entre os Comportamentos Bulímicos e as formas de autocriticismo FSCRS_eu detestado e FSCRS_total. Na subamostra Andebol constataram-se associações significativas entre a Motivação para a Magreza e a forma de autocriticismo FSCRS_eu inadequado e FSCRS_total. A dimensão FSCRS_eu detestado mostrou predizer, na subamostra Ballet, a Motivação para a Magreza e os Comportamentos Bulímicos. Na subamostra Andebol o BES_Peso foi o preditor significativo da Motivação para a Magreza. Discussão: É preocupante a percentagem de eventual PCA (em ambas em subamostras) bem como a percentagem de jovens que praticam Ballet com um IMC indicador de magreza, principalmente por serem jovens atletas e estarem mais focadas no seu corpo e forma física, estando mais vulneráveis ao desenvolvimento da patologia. É um contributo fundamental deste trabalho verificar associações (bem como o papel preditivo) nestas duas modalidades desportivas, separadamente, entre as formas de autocriticismo e as dimensões do TAA-25 Motivação para a Magreza e Comportamentos Bulímicos. Parece essencial o desenvolvimento de ações de sensibilização junto dos professores/treinadores, com o intuito de despertar uma maior atenção para a visão crítica das suas bailarinas/atletas em relação ao seu corpo, que parece influenciar as suas atitudes alimentares. Será importante iniciar estas ações/intervenções precocemente (antes mesmo da adolescência) não esquecendo a inclusão das figuras paternas, com vista a melhorar o seu sucesso, tendo consciência que particularmente no “nicho” desportivo do ballet a imagem/aparência e o peso continuam e continuarão, muito provavelmente, a ser valorizados e reforçados. / Introduction: Eating Disorders are a major public health problem. Few studies in Portugal associate this theme with areas such as self-criticism and body esteem. Thus, our main objectives are: to explore, in a sample of female adolescents, the differences between ballet and handball practitioners as to symptoms of eating disorders, body mass index (BMI) and evaluative dimensions of appearance and self-criticism levels; to analyze whether higher levels of self-criticism and a more derogatory vision in terms of appearance are associated with higher levels of PCA symptoms (in both sports). Having these associations into account, we intend to perform predictive analysis, controlling the influence of symptoms of depression, anxiety and stress. Methodology: Our sample is composed by 105 female adolescents (n = 52; 49.5% from ballet and n = 53; 50.5% from handball) with ages between 12 and 18 years (M = 14.5; DP = 1.80). The participants filled in a protocol composed by a sociodemographic questionnaire, the Forms of Self-Criticizing and Reassuring Scale (FSCRS), the Eating Attitudes Test-25 (TAA-25/EAT-25), the Body Esteem Scale (BES) and Depression, Anxiety and Stress Scale (DASS-21). Results: There were worrying percentages of eventual PCA (cutoff of 19) in Ballet practitioners (7.7%) and Handball (9.4%). As to the BMI, in the sample of practitioners of ballet we found a significant percentage of young people with malnutrition (34.6%). Ballet and Handball practitioners only differed in BMI and in the inadequate self form (higher values in Handball practitioners). In the Ballet subsample there were significant associations between Motivation for thinness and forms of self-criticism, inadequate self form, hated self form, reassure self form and total self criticism and between Bulimic behaviors and inadequate self form and total self criticism. In the Handball subsample, significant associations were found between Motivation for thinness, the inadequate self form and total self criticism. The hated self form predicted, in the Ballet subsample, Motivation for thinness and Bulimic behaviors. In the subsample Handball BES_Weight was the significant predictor of Motivation for thinness. Discussion: The percentage of any Eating Disorders (in both subsamples) and the percentage of young people who practice ballet with a IMC indicating thinness is worrying, especially in young athletes who are more focused on their body and physical form, being more vulnerable to develop these disorders/symptoms. A major contribution of this work is to have shown the associations (as well as the predictive role), in these two sports, separately, between self-criticism forms and the TAA-25 dimensions Motivation for thinness and Bulimic behaviors. It seems essential to develop awareness-raising among teachers/trainers, in order to raise greater attention to the critical view of their dancers / athletes in relation to their body, which seems to influence their eating attitudes. It will be important to start these actions/interventions earlier (even before adolescence) not forgetting the inclusion of parents in order to improve their success, particularly in the ballet “niche”, where image/appearance and weight will most likely continue to be valued and reinforced.

Real, rubber or virtual: The vision of “one’s own” body as a means for pain modulation. A narrative review

In the last few years a branch of pain research has been focussing on the modulatory effects of the vision of the body on pain perception. So, for instance, the vision of one’s own real body has been proven to induce analgesic effects. On the other hand, bodily illusions such as the rubber hand illusion have provided new tools for the study of perceptual processes during altered body ownership states. Recently, new paradigms of body ownership made use of a technology that is going places both in clinical and in experimental settings, i.e. virtual reality. While the vision of one’s own real body has been proven to yield compelling analgesic effects, slightly more controversial are those attributed to the vision of “owned” dummy bodies. This review will discuss the studies that examined the effects on pain perception of the vision of the own body, with or without body ownership illusions.

Assessments of body composition and bone parameters of lactating rats treated with diet containing flaxseed meal (Linum usitatissinum) during post-weaning period

Introduction: There are few studies on body composition and the effects of diet on weight postpartum women. The aim was to evaluate the body composition and bone parameters in lactating rats treated with diet containing flaxseed flour during postweaning period. Methods: After weaning, the lactating rat were divided in control (n = 6) and experimental (F, n = 6) group, treated with 25% flaxseed flour diet. After 30 days, body composition by dual-energy X-ray absorptiometry, serum analysis, organs and intra-abdominal fat mass, femur and lumbar vertebra parameters were determined. Results: The groups showed similar food intake, body mass and bone parameters. While F group showed the following: lower body (-5%), gonadal (-17%), mesenteric (-23%) and intra-abdominal (-6%) fat mass. Increase of HDL-cholesterol (+10%) and lower glucose (-15%), triglycerides (P < 0.05, -37%) and cholesterol (P < 0.05, -21%). Conclusions: The findings highlight the effects of flaxseed for control of adiposity and to maintain a healthy biochemical profile during the postnatal period.

On the political dimension of political science – a few words about political dimension as the final judgment and reasoning

The subject of the text is the issue of the "political", which is defined as the nature and level of the final judgment and ultimate reasoning. The issues of this kind of the "political" has been attempted to distinguish in political sciences. The text focuses on: (1) the scientist as an agent for the final judgment and reasoning, (2) the subject of study of political science, (3) "theoretical strategies" in the science of politics. The latter problem has been discussed mainly on the example of Polish political science. Discussed were among others: (1) "the dilemma of scale", (2) limited operational capacity (methodological and theoretical), (3) aesthetic imagery of political life, (4) structural ignorance in the field of ontology, epistemology and methodology.