Genetic parameters of total milk yield and factors describing the shape of lactation curve in dairy buffaloes

The objective of this study was to apply factor analysis to describe lactation curves in dairy buffaloes in order to estimate the phenotypic and genetic association between common latent factors and cumulative milk yield. A total of 31 257 monthly test-day milk yield records from buffaloes belonging to herds located in the state of São Paulo were used to estimate two common latent factors, which were then analysed in a multi-trait animal model for estimating genetic parameters. Estimates of (co)variance components for the two common latent factors and cumulated 270-d milk yield were obtained by Bayesian inference using a multiple trait animal model. Contemporary group, number of milkings per day (two levels) and age of buffalo cow at calving (linear and quadratic) as covariate were included in the model as fixed effects. The additive genetic, permanent environmental and residual effects were included as random effects. The first common latent factor (F1) was associated with persistency of lactation and the second common latent factor (F2) with the level of production in early lactation. Heritability estimates for Fl and F2 were 0.12 and 0.07, respectively. Genetic correlation estimates between El and F2 with cumulative milk yield were positive and moderate (0.63 and 0.52). Multivariate statistics employing factor analysis allowed the extraction of two variables (latent factors) that described the shape of the lactation curve. It is expected that the response to selection to increase lactation persistency is higher than the response obtained from selecting animals to increase lactation peak. Selection for higher total milk yield would result in a favourable correlated response to increase the level of production in early lactation and the lactation persistency.

Enhancement of thermal stability, strength and extensibility of lipid-based polyurethanes with cellulose-based nanofibers

Cellulose was extracted from lignocellulosic fibers and nanocrystalline cellulose (NC) prepared by alkali treatment of the fiber, steam explosion of the mercerized fiber, bleaching of the steam exploded fiber and finally acid treatment by 5% oxalic acid followed again by steam explosion. The average length and diameter of the NC were between 200-250 nm and 4-5 nm, respectively, in a monodisperse distribution. Different concentrations of the NC (0.1, 0.5, 1.0, 1.5, 2.0 and 2.5% by weight) were dispersed non-covalently into a completely bio-based thermoplastic polyurethane (TPU) derived entirely from oleic acid. The physical properties of the TPU nanocomposites were assessed by Fourier Transform Infra-Red spectroscopy (FTIR), Thermo-Gravimetric Analysis (TGA), Differential Scanning Calorimetry (DSC), X-Ray Diffraction (XRD), Dynamic Mechanical Analysis (DMA) and Mechanical Properties Analysis. The nanocomposites demonstrated enhanced stress and elongation at break and improved thermal stability compared to the neat TPU. The best results were obtained with 0.5% of NC in the TPU. The elongation at break of this sample was improved from 178% to 269% and its stress at break from 29.3 to 40.5 MPa. In this and all other samples the glass transition temperature, melting temperature and crystallization behavior were essentially unaffected. This finding suggests a potential method of increasing the strength and the elongation at break of typically brittle and weak lipid-based TPUs without alteration of the other physico-chemical properties of the polymer. (C) 2012 Elsevier Ltd. All rights reserved.

Desenvolvimento e caracterização de nanocompósito de resina epóxi com nanopartículas de sílica para revestimento de dutos para transporte de petróleo

The use of polymer based coatings is a promising approach to reduce the corrosion problem in carbon steel pipes used for the transport of oil and gas in the oil industry. However, conventional polymer coatings offer limited properties, which often cannot meet design requirements for this type of application, particularly in regard to use temperature and wear resistance. Polymer nanocomposites are known to exhibit superior properties and, therefore, offer great potential for this type of application. Nevertheless, the degree of enhancement of a particular property is greatly dependent upon the matrix/nanoparticle material system used, the matrix/nanoparticle interfacial bonding and also the state of dispersion of the nanoparticle in the polymer matrix. The objective of the present research is to develop and characterize polymer based nanocomposites to be used as coatings in metallic pipelines for the transportation of oil and natural gas. Epoxy/SiO2 nanocomposites with nanoparticle contents of 2, 4, and 8 wt % were processed using a high-energy mill. Modifications of the SiO2 nanoparticles‟ surfaces with two different silane agents were carried out and their effect on the material properties were investigated. The state of dispersion of the materials processed was studied using Scanning and Transmission Electron Microscopy (SEM and TEM) micrographs. Thermogravimetric analysis (TG) were also conducted to determine the thermal stability of the nanocomposites. In addition, the processed nanocomposites were characterized by dynamic mechanical analysis (DMA) to investigate the effect of nanoparticles content and silane treatment on the viscoelastic properties and on the glass transition temperature. Finally, wear tests of the pin-on-disc type were carried out to determine the effects of the nanoparticles and the silane treatments studied. According to the results, the addition of SiO2 nanoparticles treated with silane increased the thermal stability, the storage modulus and Tg of the epoxy resin and decreased wear rate. This confirms that the interaction between the nanoparticles and the polymer chains plays a critical role on the properties of the nanocomposites

Avaliação tribológica dos polímeros NBR, PTFE e PTFE gravitado em contato com aço AISI 52100

Low cost seals are made of NBR, Nitrile Butadiene Rubber, a family of unsaturated copolymers that is higher resistant to oils the more content of nitrile have in its composition, although lower its flexibility. In Petroleum Engineering, NBR seal wear can cause fluid leakage and environmental damages, promoting an increasing demand for academic knowledge about polymeric materials candidate to seals submitted to sliding contacts to metal surfaces. This investigation aimed to evaluate tribological responses of a commercial NBR, hardness 73 ± 5 Sh A, polytetrafluoroethylene (PTFE), hardness 60 ± 4 HRE and PTFE with graphite, 68 ± 6 HRE. The testings were performed on a sliding tribometer conceived to explore the tribological performance of stationary polymer plane coupons submitted to rotational cylinder contact surface of steel AISI 52100, 20 ± 1 HRC Hardness, under dry and lubricated (oil SAE 15W40) conditions. After screening testings, the normal load, relative velocity and sliding distance were 3.15 N, 0.8 m/s and 3.2 km, respectively. The temperatures were collected over distances of 3.0±0.5 mm and 750±50 mm far from the contact to evaluate the heating in this referential zone due to contact sliding friction by two thermocouples K type. The polymers were characterized through Thermogravimetric Analysis (TGA), Differential Scanning Calorimetry (DSC) and Dynamic Mechanical Analysis (DMA). The wear mechanisms of the polymer surfaces were analyzed by Scanning Electron Microscopy (SEM) and EDS (Energy-Dispersive X-ray Spectroscopy). NBR referred to the higher values of heating, suggesting higher sliding friction. PTFE and PTFE with graphite showed lower heating, attributed to the delamination mechanism

Escala de atitudes frente ao HIV/AIDS: análise de fatores

OBJETIVO: Este trabalho apresenta resultados acerca das propriedades psicométricas da Escala de atitudes frente ao HIV/AIDS. Os dados, provenientes de uma amostra de 549 alunos entre universitários, ensinos médio e ensino fundamental. MÉTODOS: Os dados foram tratados pelo método dos componentes principais da análise fatorial. A análise final, postulado um eigenvalue mínimo de 2, resultou cinco fatores. Foram eliminados itens que apresentaram carga fatorial menor que 0,30. Neste estudo, o menor alfa observado foi de 0,79. Portanto, é provável que todos os 47 itens do instrumento final elaborado meçam o mesmo construto: atitude frente ao HIV/AIDS. RESULTADOS: Escores inferiores a 96 foram considerados fraco grau de conhecimento sobre HIV/AIDS; entre 96 e 192 moderado grau de conhecimento e acima de 192 alto grau de conhecimento sobre HIV/AIDS. Foram estabelecidos os fatores: 1, 2 e 3, sendo fator geral de percepção da informação técnico-científica; fator de percepção da informação técnico-científica versus sexualidade e preconceito; fator de percepção da informação técnico-científica no uso de drogas, respectivamente. CONCLUSÕES: O alfa de Cronbach encontrado para a escala como um todo foi de 0,859, sugerindo fortemente a existência da fidedignidade do instrumento que se mostrou útil para avaliar o grau de conhecimento acerca do HIV/AIDS e o risco decorrente do desconhecimento, entre estudantes.

Evaluation of thermal behavior of latex membranes from genetically improved rubber tree (Hevea brasiliensis)

Thermal stability, thermal decomposition process, residual mass, temperature of glass transition (T-g) and temperature dependence of storage modulus (E'), were determined for latex membranes prepared from six clones of Hevea brasiliensis: IAC 331, IAC 332, IAC 333 and IAC 334 grown at experimental plantations of Instituto Agronomico de Campinas (IAC) in Votuporanga, São Paulo State, Brazil. Latex membranes from GT1 and RRIM 600 Asian matrix clones were used as references. The thermal behavior of latex membranes from genetically improved rubber trees was characterized using thermogravimetry/derivative thermogravimetry (TG/DTG), differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA). The thermal behavior of latex from clones studied in the present work showed similar features of the clones previously reported (IAC 40, IAC 300, IAC 301, IAC 328, IAC 329 and IAC 330), with mass loss in four consecutive steps, except IAC 333, which showed an additional mass loss step. (c) 2006 Elsevier B.V. All rights reserved.

Tradução, adaptação cultural e avaliação psicométrica da prova cognitiva de leganés em uma população idosa brasileira com baixo nível de escolaridade

Introdução: The scales of cognitive screening are important tools for early detection of dementia, creating the possibility of developing measures to slow this process and assist in the management of the disease. Objective: To validate the Leganés Cognitive Test (Prueba Cognitive de Leganés) (PCL) for cognitive screening in low educated elderly Brazilians. Methods: The study sample was composed of 59 elderly residents from the city of Santa Cruz, Brazil with low schooling levels. Reliability was analyzed with a 2-day interval between assessments, and concurrent validity was assessed using the Mini Mental State Examination (MMSE). Results: According to the PCL, the prevalence of dementia was 11.8%. The scale items showed a moderate to strong correlation between domains (p <0.01), and inter-rater reliability exhibited ICC = 0.81, 95% CI (0.72-0.88). Factor analysis resulted in two factors: memory and orientation. Interscale agreement was considered poor (k = - 0.02), supporting the hypothesis of an educational impact on final MMSE scores. Conclusion: The results suggest that PCL has acceptable levels of reliability for use in low educated elderly Brazilians

Versão breve da social rhythm metric: um instrumento para avaliar ritmo social de pacientes com acidente vascular cerebral

Stroke is a neurological disorder caused by restriction of blood flow to the brain, which generates directly a deficit of functionality that affects the quality of life of patients. The aim of this study was to establish a short version of the Social Rhythm Scale (SRM), to assess the social rhythm of stroke patients. The sample consisted of 84 patients, of both sexes, with injury time exceeding 6 months. For seven days, patients recorded the time held 17 activities of SRM. Data analysis was performed using a principal components factor analysis with varimax rotation of the full version of SRM in order to determine which activities could compose brief versions of SRM. We then carried out a comparison of hits, the ALI (Level Activity Index) and SRM, between versions, by Kruskal-Walls and the Mann-Whitney test. The Spearman correlation test was used to evaluate the correlation between the score of the full version of SRM with short versions. It was found that the activities of SRM were distributed in three versions: the first and second with 6 activities and third with 3 activities. Regarding hits, it was found that they ranged from 4.9 to 5.8 on the first version; 2.3 to 3.8 in version 2 and 2.8 to 6.2 in version 3, the first the only version that did not show low values. The analysis of ALI, in version 1, the median was 29, in version 2 was 14 and in version 3 was 18. Significant difference in the values of ALI between versions 1 and 2, between 2 and 3 and between versions 1 and 3. The highest median was found in the first version, formed by activities: out of bed, first contact, drink coffee, watch TV in the evening and go to bed. The lowest median was observed in the second version and this was not what had fewer activities, but which had social activities. The medians of the SRM version 1 was 6, version 2 was 4 and version 3 was 6. Significant difference in the values of SRM between versions 1 and 2 and between 2 and 3, but no significant difference between versions 1 and 3. Through analysis, we found a significant correlation only between the full version and the version 1 (R2 = 0.61) (p <0.05), no correlation was found with version 2 (R2 = 0.007) nor with version 3 (R2 = 0.002), this was finally a factor to consider version 1 as the short brazilian version of the Social Rhythm Metric for stroke patients

Condições de saúde bucal e capacidade funcional em idosos

Population aging is one of the greatest challenges to contemporary public health and, in this perspective, the functional capacity emerges as an important feature in geriatric assessment. The oral health of elderly, in turn, deserves special attention because, historically, in the dental services, this population group was not considered a priority for attention, which is verified by high rates of edentulism found even among these individuals. The present study proposes to examine the relationship between oral health status and functional capacity in an elderly population. To this end, intra-oral epidemiological examination was performed to assess the degree of dental caries, periodontal status, use and need of prosthesis and the presence of lesions. Functional capacity was assessed by the Independence in Activities of Daily Living, which considers the independence or not in the performance of six self-care functions. Socioeconomic and demographic characteristics and general health status were also investigated, in view of the possibility of intervention of these variables in the investigated relation. An factor analysis of the principal components was conducted which resulted four indicators of oral health conditions, representative of the population studied. 441 seniors were enrolled with mean age of 71.7 (± 8.7) years, the majority being female (68%). Functional capacity was dichotomized into completely independent individuals (89.6%) and dependent on at least one of the functions considered (10.4%). There was an association between functional capacity and the indicators related to the presence of many teeth and dental caries, and to that associated with the use and need of prostheses. These associations in turn, lost statistical significance when adjusting for confounding variables, combined in separate models for each indicator. Some of these variables, however, remained associated with functional capacity. It is considered that the study of oral health status of elderly, associeted with the search for an association with functional capacity is important in the construction of indicators necessary for planning preventive and therapeutic interventions that reduce the risk for loss of ability in daily physical functions and their consequences, as the harm in the oral self-care

About the Use of the HdHr Algorithm Group in Integrating the Movement Equation with Nonlinear Terms

This work summarizes the HdHr group of Hermitian integration algorithms for dynamic structural analysis applications. It proposes a procedure for their use when nonlinear terms are present in the equilibrium equation. The simple pendulum problem is solved as a first example and the numerical results are discussed. Directions to be pursued in future research are also mentioned. Copyright (C) 2009 H.M. Bottura and A. C. Rigitano.

Adaptação e validação da escala de dependência de exercício físico em versão tradicional e informatizada

While providing physical and psychological benefits, excessive exercise could be or cause a compulsive behavior, making the individual dependent on it. In a parallel discussion, computerized psychological instruments, for a hand, reflects the development of information technology and your applicability to other areas, but also shows little advance for Psychological Assessment. In this perspective, this study aims to adapt the Exercise Dependence Scale (EDS-R) in two formats (paper-and-pencil and computerized) and evaluate evidence of factorial and convergent validity, and reliability of each version and compare them with each other. It is also proposed to observe the relationship of some bio-demographic (Sex, age, frequency, duration and intensity of practice exercise) and the exercise dependence (DEF). For this purpose, 709 regular physical activity practitioners, selected by procedures non-probabilistic sampling, responded a adapted version of EDS-R, Muscle Appearance Satisfaction Scale (MASS), Body Modification Scale (BMS) and a demographic questionnaire, analyzed through Exploratory Factor Analysis, Cronbach's Alpha and not parametric tests. Both the traditional version and the computer showed a seven factors structure, explaining 57 and 62% of the variance, respectively, and Cronbach's alphas of 0.83 and 0.89. Factors were: (1) intentionality, (2) continuity, (3) tolerance, (4) reduction of other activities, (5) lack of control, (6) abstinence and (7) time spent on exercise. Relationships were observed between the Exercise Dependence and the variables: age, diets, consumption of food supplements and medicines for weight change, desire to do plastic surgery and body satisfaction. We observed also a positive correlation between the DEF and the frequency, duration and intensity of exercise, and the factor "Dependence on exercising" from MASS, indicating convergent validity of the EDS-R. Finally, comparisons between the two formats were equivalent, with few changes: computerized version achieved higher DEF scores. Based on these results, it can be concluded that the EDS-R has factorial and convergent validity, reliability, to measure exerceise dependence on traditional e computerized formats. DEF is related to actions used to body modification and behaviors toward exercise. Finally, it was found equivalence between the formats, especially in psychometric parameters, thus suggesting feasibility of a computerized assessment. However, it was observed that the computerized data has sample recruiting strategies more limited

Significado do Trabalho e Escolha Acadêmico-Profissional: um estudo com universitários primeiranistas

Relations between the meaning attributed to work by first year university students and their academic and professional choice were analyzed. The participants were 921 students, 17-52 years old (M = 22; SD = 4.9), enrolled in 16 courses common to two college level institutions of the city of Natal, RN, one public, the other private. A questionnaire was designed for collecting data about the academic-professional choice, with open-ended and multiple choice questions. Work meaning was obtained by means of two questions on centrality and two scales pertaining to the Inventory of Motivation and Work Meaning: value and descriptive attributes. A socio-demographic set of questions ended the questionnaire. Data was entered in a SPSS (Statistical Package for the Social Sciences) database, allowing for the pertinent statistical analyses, such as frequency, t test, chi square, factor analysis, cluster analysis and ANOVA. Results indicated that the decision about academic-professional career was made by the majority of the participants (in first option, N = 921) without the adequate consideration of the socio-professional reality (80.7%) and personal internal resources (98.5%). When considering the second option (N = 654), only the first criterion was taken into account, but only by 12.5% of the sample. The main difficulties faced by students during the choosing process were, then, made apparent in the data. 46.8% of the participants were unsatisfied with the course they had started and were anticipating unpromising perspectives in relation to it. The first year students took work as the second most important aspect of their lives and demonstrated an idealized vision about it. Five patterns of work meaning were identified. In relation to centrality and the value and descriptive attributes, the university students displayed differentiation in the attribution of work meaning according to course and area of knowledge

Estudo das propriedades psicométricas da escala WHOQOLold em idosos da região Nordeste

The population aging process increases the number of elderly people worldwide. In Brazil, a country of continental size, this process began in the 40s and happens with specific features in each of the different region s realities. This way, this thesis aimed to evaluate the psychometric properties of a elderly s quality of life (QOL) scale, the WHOQOL-old, in a population of the Northeast of Brazil. We sought to investigate the congruence between the content covered by the scale and the ones deemed as relevant by the participants. It aimed also study the validity evidences of the instrument s internal structure. To achieve the research objectives we adopted the design of multiple methods. The research was organized in two studies. For data collection, both studies used a sociodemographic questionnaire to obtain a profile of the participants and the Mini Mental State Exam (MMSE), used as exclusion criterion. A number of 18 elderly residents of the cities of Natal-RN and Campina Grande-PB, mean age of 73.3 years (SD = 5.9) took part od the study, They were organized into three focal groups (FG) in witch they discussed about the concept of QOL, what enhance and what hinders QOL. For Study II, a quantitative approach, 335 elderly from Campina Grande responded scale WHOQOL-old. They are between 65 and 99 years (M = 74.17, SD = 6.5). The FG data were analyzed by categorical thematic content. For the data analysis of the WHOQOL-old scale were used exploratory factor analysis and calculation of the Akaike and Bayesian information criteria. The results of both studies were triangulated. According to the discussions in the FG, health and social participation have central roles in quality of life. Social participation is related to all the other QOL s influences raised. The participants indicated the relevance of religiosity and were divided about the importance of sexual activity. Exploratory factor analysis (EFA) extracted a model of six factors. Two items (OLD_3 and OLD_9), not loaded on any factor and were excluded. The other items had factor loadings > 0.3. The response categories were reduced from five to three. After the scale changes, the empirical model showed better fit (-2loglikelihood = 8993.90, BIC and AIC = 9183.90 = 9546.24) than the theoretical model (-2loglikelihood = 18390.88, AIC = 18678.88 and BIC = 19228.11). Despite the best information criterion values, the RMESA remained above the ideal (0.06). We conclude that the WHOQOL-old presents psychometric parameters below the ideal when used with the Northeast population, but the improvements made the scale s use acceptable. The WHOQOL-old uses observable variables that matches with the participants' perceptions on quality of life. However, new strategies must be tested for a better sacale refinement

Relação das condições socioeconômicas com as condições de saúde bucal em capitais brasileiras

Despite the improvement of Brazilian s living conditions in recent decades, this improvement occurred in a polarized way between groups of better social position. Then, there is still a health inequity´s panorama in Brazil which encompasses the oral health state. This panorama instigated the attainment of this ecological study that aimed to evaluate the relationship of socioeconomic conditions, and public health policies with oral health status in Brazilian capitals. Thus, we performed factor analysis and linear regression using oral health indicators collected from SB Brasil 2010, of socioeconomic conditions from Brazilian Census 2010 and related to water´s supply fluoridation from SISAGUA. Factor analysis with indicators of living conditions revealed two common factors, economic deprivation and socio-sanitary condition. Economic deprivation showed statistically significant positive correlation with DMFT 12 years (p= 0,03) and mean missing teeth (p = 0,002) and negative correlation with caries-free population (p=0,012). Socio-sanitary negatively correlated with DMFT (p <0,0001) and a positive correlation with caries-free population (p = 0.002). Fluoridated water had a significant association with DMFT (p <0,0001), mean missing teeth (p <0,0001) and caries free population (p <0.0001). Multiple linear regression analysis for the DMFT of capital was estimated by socio-sanitary condition and fluoridation, adjusted by economic deprivation, whereas the model for the mean missing teeth was estimated only by fluoridation and economic deprivation, and finally the model the rate for the population free of caries in Brazilian capitals was estimated by economic and socio-sanitary status adjusted fluoridated water supply. Therefore, factors related to living conditions and public policies are intrinsically linked to tooth decay issues. Thus, actions, beyond dental care assistance, must be development to impact positively in social and economic conditions, especially, between the most vulnerable populations

Perfil de mortalidade de idosos no Rio Grande do Norte: estudo comparativo entre duas faixas etárias e fatores relacionados

Measures of mortality represent one of the most important indicators of health conditions. For comprising the larger rate of deaths, the study of mortality in the elderly population is regarded as essential to understand the health situation. In this sense, the present study aims to analyze the mortality profile of the population from 60 to 69 (young elders) and older than 80 years old (oldest old) in the Rio Grande do Norte state (Brazil) in the period 2001 to 2011, and to identify the association with contextual factors and variables about the quality of the Mortality Information System (SIM). For this purpose, Mortality Proportional (MP) was calculated for the state and Specific Mortality Rate by Age (CMId) , according to chapters of ICD- 10, to the municipalities of Rio Grande do Norte , through data from the Mortality Information System (SIM) and the Brazilian Institute of Geography and Statistics (IGBE). In order to identify groups of municipalities with similar mortality profiles, Nonhierarchical Clustering K-means method was applied and the Factor Analysis by the Principal Components Analysis was resort to reduce contextual variables. The spatial distribution of these groups and the factors were visualized using the Spatial Analysis Areas technique. During the period investigated, 21,813 younger elders deaths were recorded , with a predominance of deaths from circulatory diseases (32.75%) and neoplasms (22.9 %) . Among the oldest old, 50,637 deaths were observed, which 35.26% occurred because of cardiovascular diseases and 17.27% of ill-defined causes. Clustering Analysis produced three clusters to the two age groups and Factor Analysis reduced the contextual variables into three factors, also the sum of the factor scores was considered. Among the younger elders, the groups are called misinformation profile, development profile and development paradox, which showed a statistically significant association with education and poverty and extreme poverty factors, factorial sum and the variable related to underreporting of deaths. Misinformation profile remained in the oldest old group, accompanied by the epidemiological transition profile and the epidemiological paradox, that were statistically associated with the development and health factor, as well as with the variables that indicate the SIM quality: proportion of blank fields about the schooling and underreporting. It proposed that the mortality profiles of the younger elders and oldest old differ on the importance of the basic causes and that are influenced by different contextual aspects , observing that 60 to 69 years group is more affected by such aspects. Health inequalities can be reduced by measures aimed to improve levels of education and poverty, especially in younger elders, and by optimizing the use of health services, which is more associated to the oldest old health situation. Furthermore, it is important to improve the quality of information for the two age groups