Investigando o uso do sentido háptico na visualização de dados multivariados em gráficos de dispersão bidimensionais

Data Visualization is widely used to facilitate the comprehension of information and find relationships between data. One of the most widely used techniques for multivariate data (4 or more variables) visualization is the 2D scatterplot. This technique associates each data item to a visual mark in the following way: two variables are mapped to Cartesian coordinates so that a visual mark can be placed on the Cartesian plane; the others variables are mapped gradually to visual properties of the mark, such as size, color, shape, among others. As the number of variables to be visualized increases, the amount of visual properties associated to the mark increases as well. As a result, the complexity of the final visualization is higher. However, increasing the complexity of the visualization does not necessarily implies a better visualization and, sometimes, it provides an inverse situation, producing a visually polluted and confusing visualization—this problem is called visual properties overload. This work aims to investigate whether it is possible to work around the overload of the visual channel and improve insight about multivariate data visualized through a modification in the 2D scatterplot technique. In this modification, we map the variables from data items to multisensoriy marks. These marks are composed not only by visual properties, but haptic properties, such as vibration, viscosity and elastic resistance, as well. We believed that this approach could ease the insight process, through the transposition of properties from the visual channel to the haptic channel. The hypothesis was verified through experiments, in which we have analyzed (a) the accuracy of the answers; (b) response time; and (c) the grade of personal satisfaction with the proposed approach. However, the hypothesis was not validated. The results suggest that there is an equivalence between the investigated visual and haptic properties in all analyzed aspects, though in strictly numeric terms the multisensory visualization achieved better results in response time and personal satisfaction.

Impact on quality of life of removable partial denture wearers after 2 years of use

The use of clinical indicators of satisfaction (OHIP) can be applied to evaluate the impact of denture use on patient quality of life, since dental problems and disorders interfere in the normal life of individuals. Aim: This study aimed at evaluating the satisfaction level of patients rehabilitated with removable partial dentures (RPD) after 2 years of use. Methods: An observational study was carried out on 28 patients with a mean age of 45 years, treated with RPD at the Department of Dentistry of the Federal University of Rio Grande do Norte in 2005. Patients signed informed consent and answered the Oral Health Impact Profile (OHIP) questionnaire on three occasions: prior to rehabilitation and at 3 months and 2 years of denture use. Repeated-measures ANOVA was applied for data analysis. Results: A difference was found between data obtained at the moment of fitting and three months after denture use (p<0.001). However, no variation was observed when comparing data from 3 months and 2 years of use (p>0.05). The variables of gender and age did not interfere in the result (p>0.05). Conclusions: The degree of patient satisfaction after RPD installation was significant at the moment of fitting and 3 months after denture use, but no significant difference was found between 3 months and 2 years of denture use.

Impact on quality of life of removable partial denture wearers after 2 years of use

The use of clinical indicators of satisfaction (OHIP) can be applied to evaluate the impact of denture use on patient quality of life, since dental problems and disorders interfere in the normal life of individuals. Aim: This study aimed at evaluating the satisfaction level of patients rehabilitated with removable partial dentures (RPD) after 2 years of use. Methods: An observational study was carried out on 28 patients with a mean age of 45 years, treated with RPD at the Department of Dentistry of the Federal University of Rio Grande do Norte in 2005. Patients signed informed consent and answered the Oral Health Impact Profile (OHIP) questionnaire on three occasions: prior to rehabilitation and at 3 months and 2 years of denture use. Repeated-measures ANOVA was applied for data analysis. Results: A difference was found between data obtained at the moment of fitting and three months after denture use (p<0.001). However, no variation was observed when comparing data from 3 months and 2 years of use (p>0.05). The variables of gender and age did not interfere in the result (p>0.05). Conclusions: The degree of patient satisfaction after RPD installation was significant at the moment of fitting and 3 months after denture use, but no significant difference was found between 3 months and 2 years of denture use.

Queilite actínica: expressão imuno-histoquímica da cox-2 e avaliação do diclofenaco sódico gel como uma terapia alternativa

Actinic cheilitis (AC) is a potentially malignant disorder which affects the lip vermilion and results from chronic exposure to sunlight. Currently, it is not possible to predict which cases of AC may progress to squamous cell carcinoma, and therefore, some biomolecular markers have been researched. Cyclooxygenase 2 (COX-2) is an enzyme associated with inflammatory response which is overexpressed in oral cancer; however, little is known about the role of this protein in actinic cheilitis. About the treatment of this lesion, currently available therapeutic modalities to AC may cause cytotoxic effects and deleterious results to patients. Therefore, the aim of this study was to evaluate the immunoexpression of COX-2 in AC of different risks of malignant transformation and analyse, through clinical follow-up, the efficacy of diclofenac sodium 3% gel in the treatment of this condition. Epithelial immunoexpression of COX-2 was analysed semi-quantitatively in 90 cases of AC classified as low risk (n = 55) and high risk (n = 35) of malignant transformation, in which the scores were assigned: (0) 0 to 5% of positive cells - Negative; (1) 6 to 30% of positive cells - Low expression; (2) 31 to 100% of positive cells - High expression. The chi-square test of Pearson was conducted to verify possible associations between immunoexpression of COX-2 and histologic grade of actinic cheilitis. The weighted kappa coefficient denoted a good interobserver agreement (0.677). Nineteen patients diagnosed with AC were instructed to perform topical application of the gel three times a day for a period of 90 days. In each biweekly visit, a follow-up record was accomplished through digital photographs and after treatment was completed, two researchers analysed all the images to assess clinical aspects of the lip. Furthermore, tolerability to the drug and patient satisfaction after treatment were evaluated. COX-2 was overexpressed in 74.4% of AC cases. Both low and high-risk groups revealed predominance of score 3, followed by scores 2 and 1. There was no significant association (p = 0.315) between COX-2 expression and histological grading. Among the total number of participants of this clinical study, ten showed total remission of all clinical features of the lesion and three had partial improvement of these characteristics. One participant presented worsening of the clinical condition. In five cases, the treatment was discontinued due to development of mild adverse effects at the site of gel application. Regarding analysis of satisfaction and tolerability to the drug, most patients were fully satisfied with the therapy (n = 11) and reported that the drug was not irritating to the lips (n = 9). Our study demonstrates that high expression of COX-2 is common in AC; however, this protein was not associated with malignant transformation risk of the analysed cases. Topical application of diclofenac sodium 3% gel provided a convenient and well tolerated approach in most cases, and may be a promising alternative for the treatment of actinic cheilitis.

The intersectorial approach in providing guidance and school support. The perspective of counsellors, tutors and principals

The provision of guidance and educational support requires joint work and the collaboration of different professionals and institutions, especially when we face complex problems that require a high level of specialization and the combination of knowledge from different areas. The research has aimed to examine the proximity of the institutional system of guidance and support to school in nine Autonomous Communities, to the intersectorial approach of counselling. We present the results of a descriptive study using the survey method, which allows knowing the opinions of counsellors, tutors and principals of Primary and Secondary Compulsory Education about the collaboration with the local public services (social, health, education, and employment) in the specialized support to students and schools. The final sample consisted of 9732 subjects who were selected from a random sampling proportional to the size of the subpopulations of each Autonomous Community. Results indicate how, in general terms, there is collaboration among the school and the local public services, although not as frequently as it would be desirable. In the same way, the professionals that were interviewed believe that the collaboration with social and educational services is quite adequate, but the assessment is not as positive when health and employment services are analysed. Finally, taking into account the different professionals considered, tutors from both educational stages are the ones that show a higher degree of satisfaction with the collaboration between the school and the local public services, except in the case of social services.

Using blogs to enhance the capacity of mathematical communication in High School

The aim of this investigation is to analyze the use of the blog as an educational resource for the development of the mathematical communication in secondary education. With this aim, four aspects are analyzed: organization of mathematical thinking through communication; communication of mathematical thinking; analysis and evaluation of the strategies and mathematical thought of others; and expression of mathematical ideas using mathematical language. The research was conducted from a qualitative approach on an exploratory level, with the case study method of 4 classrooms of second grade of secondary education in a private school in Lima. The observational technique of 20 publications in the blog of the math class was applied; a study of a focal group with a sample of 9 students with different levels of academic performance; and an interview with the academic coordinator of the school was conducted. The results show that the organization of mathematical thinking through communication is carried out in the blog in a written, graphical and oral way through explanations, schemes and videos. Regarding communication of mathematical thinking, the blog is used to describe concepts, arguments and mathematical procedures with words and examples of the students. The analysis and evaluation of the strategies and mathematical thinking is performed through comments and debates about the publications. It was also noted that the blog does not facilitate the use of mathematical language to express mathematical ideas, since it does not allow direct writing of symbols nor graphic representation.

Evolution of the diatoms: major steps in their evolution and a review of the supporting molecular and morphological evidence.

Over the years, many reviews of different aspects of diatom biology, ecology and evolution have appeared. Since 1993 many molecular trees have been produced to infer diatom phylogeny. In 2004, Medlin & Kaczmarska revised the systematics of the diatoms based on more than 20 years of consistent recovery of two major clades of diatoms that did not correspond to a traditional concept of centrics and pennates and established three classes of diatoms: Clade 1 = Coscinodiscophyceae (radial centrics) and Clade 2 = Mediophyceae (polar centrics + radial Thalassiosirales) and Bacillariophyceae (pennates). However, under certain analytical conditions, an alternative view of diatom evolution, a grades of clades, has been recovered that suggests a gradual evolution from centric to pennate symmetry. These two schemes of diatom evolution are evaluated in terms of whether or not the criteria advocated by Medlin & Kaczmarska that should be met to recover monophyletic classes have been used. The monophyly of the three diatom classes can only be achieved if (1) a secondary structure of the small subunit (SSU) rRNA gene was used to construct the alignment and not an alignment based on primary structure and (2) multiple outgroups were used. These requirements have not been met in each study of diatom evolution; hence, the grade of clades, which is useful in reconstructing the sequence of evolution, is not useful for accepting the new classification of the diatoms. Evidence for how these two factors affect the recovery of the three monophyletic classes is reviewed here. The three classes have been defined by clear morphological differences primarily based on gametangia and auxospore ontogeny and envelope structure, the presence or absence of a structure (tube process or sternum) associated with the annulus and the location of the cribrum in those genera with loculate areolae. New evidence supporting the three clades is reviewed. Other features of the cell are examined to determine whether they can also be used to support the monophyly of the three classes.

Evolution of the diatoms: major steps in their evolution and a review of the supporting molecular and morphological evidence.

Over the years, many reviews of different aspects of diatom biology, ecology and evolution have appeared. Since 1993 many molecular trees have been produced to infer diatom phylogeny. In 2004, Medlin & Kaczmarska revised the systematics of the diatoms based on more than 20 years of consistent recovery of two major clades of diatoms that did not correspond to a traditional concept of centrics and pennates and established three classes of diatoms: Clade 1 = Coscinodiscophyceae (radial centrics) and Clade 2 = Mediophyceae (polar centrics + radial Thalassiosirales) and Bacillariophyceae (pennates). However, under certain analytical conditions, an alternative view of diatom evolution, a grades of clades, has been recovered that suggests a gradual evolution from centric to pennate symmetry. These two schemes of diatom evolution are evaluated in terms of whether or not the criteria advocated by Medlin & Kaczmarska that should be met to recover monophyletic classes have been used. The monophyly of the three diatom classes can only be achieved if (1) a secondary structure of the small subunit (SSU) rRNA gene was used to construct the alignment and not an alignment based on primary structure and (2) multiple outgroups were used. These requirements have not been met in each study of diatom evolution; hence, the grade of clades, which is useful in reconstructing the sequence of evolution, is not useful for accepting the new classification of the diatoms. Evidence for how these two factors affect the recovery of the three monophyletic classes is reviewed here. The three classes have been defined by clear morphological differences primarily based on gametangia and auxospore ontogeny and envelope structure, the presence or absence of a structure (tube process or sternum) associated with the annulus and the location of the cribrum in those genera with loculate areolae. New evidence supporting the three clades is reviewed. Other features of the cell are examined to determine whether they can also be used to support the monophyly of the three classes.

Effect of the processing conditions on the microstructure and properties of rotational molded polyamide 11

Rotomolded containers for solvents and hydrocarbons require the use of high-permeability resins such as polyamide (PA). The published studies with this material are very scarce. In this work, a commercial grade of PA11 was rotational-molded using different processing temperatures and characterized with a range of techniques. The study aims at investigating the influence of the processing conditions on the microstructure and properties of molded parts. The results showed that the spherulitic morphology and the mechanical properties are affected by the processing temperature, the optimum processing range being between 220°C and 240°C. Overheating causes a decrease of the impact strength and a severe increase in the formation of pinholes at the outer surface due to polymer degradation and formation of volatile products. The thermo-oxidation reactions occurring at the inner surface of the samples result in the formation of products that absorb in the UV and visible light regions and cause the microhardness and the melt viscosity of the material to increase. The extent and severity of the degradation at the inner surface may be easily assessed by fluorescence microscopy. © 2008 Wiley Periodicals, Inc.

Public Perceptions of the Midwest's Pavements - Executive Summary: Iowa

This report summarizes Iowa results of a five year, Pooled Fund study involving the Wisconsin, Iowa, and Minnesota Departments of Transportation (DOTs) designed to 1) assess the public's perceptions of the DOTs' pavement improvement strategies and 2) develop customer-based thresholds of satisfaction with pavements on rural two lane highways in each state as related to the DOTs' physical indices, such as pavement ride and condition. The primary objective was to seek systematic customer input to improve the DOTs' pavement improvement policies by 1) determining how drivers perceive the DOTs' pavements in terms of comfort and convenience but also in terms of other tradeoffs the DOTs had not previously considered, 2) determining relationships between perceptions and measured pavement condition thresholds (including a general level of tolerance of winter ride conditions in two of the states), and 3) identifying important attributes and issues that may not have been considered in the past. Secondary objectives were 1) to provide a tool for systematic customer input in the future and 2) to provide information which can help structure public information programs. A University of Wisconsin-Extension survey lab conducted the surveys under the direction of a multi-disciplinary team from Marquette University. Approximately 4500 drivers in the 3 states participated in the 3 phases of the project. Researchers conducted 6 focus groups in each state, approximately 400 statewide telephone interviews in each state and 700-800 targeted telephone interviews in each state. Approximately 400 winter ride interviews were conducted in Wisconsin and Minnesota. A summary of the method for each survey is included. In Phase I, focus groups were conducted with drivers to get an initial indication of what the driving public believes in regards to pavements and to frame issues for inclusion in the more representative statewide surveys of drivers conducted in Phase II. Phase II interviews gathered information about improvement policy tradeoff issues and about preliminary thresholds of improvement in terms of physical pavement indices. In Phase III, a two step recruitment and post-drive interview procedure yielded thresholds of ride and condition index summarized for each state. Results show that, in general, the driving public wants longer lasting pavements and are willing to pay for them. They want to minimize construction delay, improve entire sections of highway at one time but they dislike detours, and prefer construction under traffic even if it stretches out construction time. Satisfaction with pavements does not correlate directly to a high degree with physical pavement indices, but was found instead to be a complex, multi-faceted phenomenon. A psychological model was applied to explain satisfaction to a respectable degree for the social sciences. Results also indicate a high degree of trust in the 3 DOTs which is enhanced when the public is asked for input on specific highway segments. Conclusions and recommendations include a 3-step methodology for other state studies.

Redes Sociais Pessoais de Idosos, Satisfação com as Relações Interpessoais e Confiança

Objetivos: O presente estudo tem como objetivo geral caracterizar as redes sociais pessoais dos idosos com idade igual ou superior a 65 anos, analisando-as segundo o nível de satisfação com as relações interpessoais e a confiança nos outros. Metodologia: Este é um estudo descritivo e correlacional, privilegiando a análise bivariada. Os dados foram recolhidos através do Instrumento de Análise da Rede Social Pessoal, IARSP-Idosos (Guadalupe, 2009; Guadalupe & Vicente, 2012) e de uma escala de avaliação da Satisfação com as Relações Interpessoais, construída para o efeito, e de uma questão relacionada com a Confiança. Participantes: A amostra é constituída por 446 indivíduos, maioritariamente do sexo feminino (n=285; 63,9%), com idades compreendidas entre os 65 e os 98 anos; a maioria tem filhos (n = 389; 87,2%), e cerca de 80,0% (n = 357) vivem na sua casa, sendo a zona de residência essencialmente rural (61,2%; n = 273). A maioria tem escolaridade (65,9%; n = 294), sobretudo ao nível do quarto ano (n= 226; 50,7%). Resultados: Os resultados demonstram que os idosos do sexo feminino, com ≤ 75 anos, casado/a ou em união de fato, com filhos, que vivem acompanhados, com o 4ª ano de escolaridade e que não registam qualquer corte relacional, são os que mais confiam nos outros. Registam-se diferenças nas características funcionais da rede segundo esta variável, o que não acontece nas estruturais, com a exceção da proporção das relações com técnicos (p = 0,042) e nas relacionais-contextuais. A confiança nas pessoas com quem se relaciona correlaciona-se de forma positiva e estatisticamente significativa com a satisfação com os filhos, com os netos, com outros parentes, com os amigos e com os vizinhos (p<0,001). Conclusões: Numerosas variáveis sociodemográficas não aparentam estar relacionadas com a confiança nas pessoas com quem os idosos se relacionam, nas múltiplas dimensões consideradas. Em contrapartida, as variáveis que aparecem relacionadas com a confiança, são aquelas que, de forma mais ou menos direta, estão igualmente associadas ao domínio pessoal. É de salientar que no que respeita a esta variável se verificam diferenças nas características funcionais da rede o que não acontece nas estruturais e nas relacionais-contextuais. As relações familiares de filhos, netos e outros parentes são as que mais se associam à confiança e ao apoio social percebido pelos idosos, o qual é complementado por outras relações interpessoais, designadamente as que são estabelecidas com amigos e vizinhos. / Objetives: This study has the general objective to characterize the personal social networks of the elderly aged over 65 years, analyzing them according to the level of satisfaction with interpersonal relationships and trust in others. Methodology: This is a descriptive and correlational study, focusing on bivariate analysis. Data were collected through the Personal Social Networks Analysis Tool, IARSP-Elderly (Guadalupe, 2009; Vicente & Guadalupe, 2012) and a scale measuring satisfaction with interpersonal relations, purpose built, and a question related to the trust. Participants: The sample includes 446 individuals, mostly female (n = 285; 63,9%), aged between 65 and 98 years old; most have sons/daughters (n = 389; 87,2%), and about 80,0% (n = 357) are living in their home, mostly in rural areas (61,2%, n = 273). The majority have education (65,9%, n = 294), especially at the level of the fourth year (n = 226; 50,7%). Results: The results show that the elderly female, with <= 75, married, with children, living together, with the 4th grade, and did not record any relational cut, are the ones that rely in the others. We found differences in the functional characteristics of the network according to this variable, what does not happen on the structural variables, with the exception of the proportion of relations with workers in social services (p = 0,042), and on the relational-contextual. The confidence in the people he meets, correlates positively and statistically significant satisfaction with the children, with grandchildren, other relatives, friends and neighbors (p <0,001) Conclusions: Numerous sociodemographic variables do not appear to be related to trust in the interpersonal relationship, in the multiple dimensions considered. In contrast, the variables which appear related to trust are those which are associated with the personal domain. It is noteworthy that we have found differences in the functional characteristics of the network but not in the structural and the relational-contextual. Family relationships of children, grandchildren and other relatives are the most associated to the confidence and social support perceived by the elderly, which is complemented by other interpersonal relationships, including those with established friends and neighbors.

Participação Social e Redes Sociais Pessoais de Idosos

Objetivo: O objetivo central deste estudo é caracterizar as redes sociais pessoais de indivíduos com idade igual ou superior a 65 anos, a nível estrutural, funcional e relacional-contextual, analisando-as segundo o nível de participação social dos idosos ao longo da sua vida em estruturas comunitárias ligadas ao lazer, cultura, desporto, religião e voluntariado. Metodologia: Para a avaliação das variáveis em estudo foram utilizados o Instrumento de Análise da Rede Social Pessoal, versão para idosos (IARSP – Idosos) (Guadalupe, 2010; Guadalupe & Vicente, 2012) para avaliar as dimensões da rede social pessoal, um questionário para caracterizar as variáveis sociodemográficas e a participação social e a Satisfaction With Life Scale – SWLS (Diener, 1985) que permite avaliar o grau de satisfação com a vida. Participantes: A amostra é constituída por 567 idosos, com uma média de idades de 75 anos (DP=7,6), entre os 65 anos e os 98 anos, maioritariamente do sexo feminino (63,0%), casados ou em união de facto (53,7%) e com escolaridade (69,8%), sobretudo ao nível do quarto ano (51,3%). A maioria dos idosos inquiridos não vive só (79,4%) numa zona de residência maioritariamente inserida em aglomerado populacional em região rural (57,0%) e não usufrui de qualquer tipo de apoio de resposta social (75,5%). Resultados: A amostra divide-se entre os que participaram comunitariamente ao longo da vida (47,8%; n = 271) e os que não participaram (52,2%; n = 296), sendo que entre os que participam 16,7% fazem-no com elevada frequência. Os idosos do sexo feminino, com idade igual ou inferior a 75 anos, casados, com habilitações literárias e que vivem acompanhados, são os que têm uma maior probabilidade de ter uma participação social mais ativa. Os idosos que apresentam participação social têm uma rede maior, com um membro a mais em média (M = 8,52 vs. 7,51, p = 0,027), e uma composição distinta dos que não participam, com menor peso das relações familiares (M = 72,61% vs. 80,81%, p < 0,001), maior peso e mais relações de amizade (M = 15,43% vs. M = 9,24%, p < 0,001) e maior presença de relações de trabalho (M = 1,11% vs. 0,13%, p = 0,006). Relativamente às características funcionais, podemos constatar que a reciprocidade de apoio é percebida como maior (p = 0,010) entre os idosos que participam comunitariamente, não se verificando diferenças noutras variáveis funcionais e relacionais-contextuais. O nível de participação e a satisfação com o nível de participação correlacionam-se positivamente com a satisfação percebida com a vida (p < 0,001). Conclusão: As conclusões apontam para um efeito da participação social ao longo da vida em estruturas comunitárias nas características estruturais das redes sociais pessoais dos idosos, não se verificando interferência na maioria das características funcionais e nas relacionais-contextuais. Verificámos ainda que há uma associação entre a participação social e a satisfação com a vida, sendo mais satisfeitos os que participam em estruturas comunitárias. É possível constatar que a rede daqueles que referem ter participação social é tendencialmente maior e heterogénea na composição, quando comparada com as redes dos sem participação social, assumindo, assim, relevância na estruturação de uma rede mais diversa e ampla, devendo ser estimulada no sentido de promover uma rede com recursos potencialmente positivos e um envelhecimento mais ativo. / Objectives: The central objective of this study is to characterize the personal social networks of the elderly, aged 65 years or more, analyzing them according to the level of social participation throughout their life in community structures related to leisure, culture, sports, religion and volunteering. Methodology: For the evaluation of the variables we used the Social Network Analysis Tool (IARSP-elderly) (Guadalupe, 2010; Guadalupe Vicente, 2012) to assess the dimensions of the social network; a questionnaire to evaluate social participation; and the Satisfaction With Life Scale SWLS – (Diener, 1985) to acess the degree of satisfaction with life. Participants: The sample consists of 567 elderly, with an average age of 75 years old (SD = 7,595), between 65 and 98 years old, mostly female (63.0 %), married (53.7%) with education (69.8%), mainly with the 4th grade (51.3%). Most of the respondents do not live alone (79.4%) in agglomerations in rural region (57.0%) and are not users of social services (75.5%). Results: The sample is divided between those who had community participation throughout life (47.8 %; n = 271) and those who did not participated (52,2%; n = 296). Between the first, 16.7% do it with high frequency. The elderly women, aged less than 75 years old, married, with educational qualifications and living not alone, are those who have a higher likelihood of having a more active social participation. The elderly that present social participation have a larger network, with one more member (M = 8,52 vs. 7,51, p = 0,027), and a composition distinct from not participating, with less proportion of family relations (M = 72,61% vs. 80,81%, p < 0,001), greater proportion and more friendships (M = 15,43% vs. M = 9,24%, p < 0,001) and greater presence of working relations (M = 1,11% vs. 0,13%, p = 0,006). Regarding the functional dimension, the reciprocity of support is perceived as higher (p = 0.010) among seniors participating in community and there were no differences in other functional and relational-contextual variables. The level of participation and satisfaction with the level of participation correlate positively with perceived satisfaction with life (p <0.001). Conclusion: The findings point to an effect of lifelong social participation in community in structural characteristics of personal social networks of the elderly, not verifying interference in most of the functional and the contextual-relational characteristics. We have also found that there is an association between social participation and life satisfaction, being more satisfied when they participate in community structures. The social network of the elderly who reported having social participation tends to be larger and heterogeneous in composition compared with those without social participation, thus assuming importance in structuring a more diverse and extensive network, should be encouraged in order to promote a network with potentially positive resources and a more active aging.

Aprendizaje basado en problemas, ABP : una propuesta para transformar la enseñanza-aprendizaje de las aplicaciones de la trigonometría en la solución de triángulos en el grado 10º

El estudio tuvo como propósito determinar la efectividad relativa del ABP, comparado con el método tradicional para desarrollar habilidades de resolución de problemas en el aprendizaje de las aplicaciones de la solución de triángulos en el grado 10º de la Institución Educativa El Progreso, de El Carmen de Viboral, Antioquia. La enseñanza-aprendizaje de las matemáticas sustentadas con la estrategia didáctica Aprendizaje Basado en Problemas permite a los estudiantes y docentes aproximarse al conocimiento de una manera similar a como lo hacen los científicos; el primer paso es una situación de duda, perplejidad del estudiante provocada por la Situación Problema planteada por el docente, el segundo un momento de “sugerencias” en las que la mente salta hacia adelante en busca de una posible solución (Dewey, 1933, p. 102). El tercer paso “intelectualización” de la dificultad que se ha percibido para convertirlo en un problema que debe solucionarse (Dewey, 1933, p. 103). La cuarta es “la idea conductora o hipótesis”, las cuales se basan en la formulación de explicaciones sugeridas o soluciones posibles (Dewey, 1933, p. 104). El quinto paso sería el “razonamiento”, consiste en la elaboración racional de una idea que se va desarrollando de acuerdo a las habilidades de cada persona (Dewey, 1933, p. 105). El paso final es la “comprobación de hipótesis” en situaciones reales. Este proceso se evidenció a través de cuatro Situaciones-Problema enfocadas desde un contexto auténtico “la remodelación del parque principal de El Carmen de Viboral” con el objetivo de motivar a los estudiantes para el aprendizaje de algunos conceptos matemáticos y el desarrollo de habilidades de resolución de problemas. La metodología de la investigación fue un diseño cuasi-experimental con grupo experimental compuesto por 38 estudiantes del grado 10º2 y grupo control con 37 estudiantes del grado 10º1. Se empleó como técnica de recolección de la información una prueba pre-test antes del tratamiento y una prueba post-test que se aplicó después del tratamiento a ambos grupos; se aplicó también una escala de satisfacción de los estudiantes con la metodología tradicional en ambos grupos y una escala de satisfacción con la estrategia didáctica ABP sólo al grupo experimental; la observación directa, y el portafolio que evidenciaba todas las construcciones de los estudiantes. La aplicación de la estrategia didáctica experimental se aplicó durante 4 meses, con una intensidad horaria de cuatro horas semanales, tiempo durante el cual se implementaron las cuatro Situaciones-Problema. Se concluyó entre otros aspectos que el 86,5% de los estudiantes encuentran las clases de matemáticas como interesantes, contextualizadas, aplicables y significativas, mientras que antes del tratamiento sólo el 44,4% se encontraba satisfecho con las clases de matemáticas, con una diferencia en cambio de actitud de 42,1% frente a las clases de matemáticas con la metodología tradicional. En el análisis comparativo de adquisición de competencias específicas se demuestra que el grupo experimental demostró ser matemáticamente más competente con respecto al grupo control en todas las competencias evaluadas: capacidad de modelación, inductiva, comunicativa y habilidad procedimental. Además, el proyecto de investigación tuvo un valor agregado: 10 estudiantes tuvieron la oportunidad de conocer más sobre su cultura ceramista mediante el diseño y construcción de mosaicos que los ofreció la casa de la cultura en forma gratuita.

Study of white spot disease in four native species in Persian Gulf by histopathology and PCR methods

After serious disease outbreak, caused by new virus (WSV), has been occurring among cultured penaeid shrimps in Asian countries like China since 1993 and then in Latin American countries, during June till July 2002 a rapid and high mortality in cultured Penaeus indicus in Abadan region located in south of Iran with typical signs and symptoms of White Spot Syndrome Virus was confirmed by different studies of Histopathology, PCR, TEM, Virology. This study was conducted for the purpose of determination of prevalence(rate of infection)/ROI and grading severity (SOI) of WSD to five species: 150 samples of captured shrimps and 90 samples of cultured ones; Penaeus indicus, P. semisulcatus, P. merguiensis, Parapenaopsis styliferus, and Metapenaeus affinis in 2005. 136 of 240 samples have shown clinical and macroscopical signs & symptoms including; white spots on carapase (0.5-2 mm), easily removing of cuticule, fragility of hepatopancreas and red color of motility limbs. Histopathological changes like specific intranuclear inclusion bodies (cowdry-type A) were observed in all target tissues (gill, epidermis, haemolymph and midgut) but not in hepatopancreas, among shrimps collected from various farms in the south and captured ones from Persian Gulf, even ones without clinical signs. ROI among species estimated, using the NATIVIDAD & LIGHTNER formula(1992b) and SOI were graded, using a generalized scheme for assigning a numerical qualitative value to severity grade of infection which was provided by LIGHTNER(1996), in consideration to histopathology and counting specific inclusion bodies in different stages(were modified by B. Gholamhoseini). Samples with clinical signs, showed grades more than 2. Most of the P. semisulcatus and M. affinis samples showed grade of 3, in the other hand in most of P. styliferus samples grade of 4 were observed, which can suggest different sensitivity of different species. All samples were tested by Nested PCR method with IQTm 2000 WSSV kit and 183 of 240 samples were positive and 3 1evel of infection which was shown in this PCR confirmed our SOI grades, but they were more specified.

The multistage crystallization of zircon in calc-alkaline granitoids : U-Pb age constraints on the timing of Variscan tectonic activity in SW Iberia

CL imaging and U–Th–Pb data for a population of zircons from two of the Évora Massif granitoids (Ossa-Morena Zone, SW Iberia) show that both calc-alkaline granitoids have zircon populations dominated by grains with cores and rims either showing or not showing differences in Th/U ratio, and having ages in the range ca. 350–335 Ma (Early Carboniferous). Multistage crystallization of zircon is revealed in two main growth stages (ca. 344–342 Ma and ca. 336–335 Ma), well represented by morphologically complex zircons with cores and rims with different ages and different Th/U ratios that can be explained by: (1) crystallization from melts with different compositions (felsic peraluminous to felsic-intermediate metaluminous; 0.001 Th/U ratio < 0.5) and (2) transient temperature fluctuations in a system where anatectic felsic melts periodically underwent injection of more mafic magmas at higher temperatures. The two studied calc-alkaline granitoids do not include inherited zircons (pre-Carboniferous), probably because they were formed at the highest grade of metamorphism (T 837 °C; granulite facies) and/or because they were derived from inheritance-poor felsic and mafic rocks from a previous cycle, as suggested by the internal structures of zircon cores. These Variscan magmatic rocks with crystallization ages estimated at ca. 336–335 Ma are spatially and temporally related to high-temperature metamorphism, anatexis, processes of interaction between crustal- and mantle-derived magmas and intra-orogenic extension that acted in SW Iberia during the Early Carboniferous.