Tutorial: Multivariate Classification for Vibrational Spectroscopy in Biological Samples

Vibrational spectroscopy techniques, such as Fourier-transform infrared (FTIR) and Raman spectroscopy, have been successful methods for studying the interaction of light with biological materials and facilitating novel cell biology analysis. Spectrochemical analysis is very attractive in disease screening and diagnosis, microbiological studies and forensic and environmental investigations because of its low cost, minimal sample preparation, non-destructive nature and substantially accurate results. However, there is now an urgent need for multivariate classification protocols allowing one to analyze biologically derived spectrochemical data to obtain accurate and reliable results. Multivariate classification comprises discriminant analysis and class-modeling techniques where multiple spectral variables are analyzed in conjunction to distinguish and assign unknown samples to pre-defined groups. The requirement for such protocols is demonstrated by the fact that applications of deep-learning algorithms of complex datasets are being increasingly recognized as critical for extracting important information and visualizing it in a readily interpretable form. Hereby, we have provided a tutorial for multivariate classification analysis of vibrational spectroscopy data (FTIR, Raman and near-IR) highlighting a series of critical steps, such as preprocessing, data selection, feature extraction, classification and model validation. This is an essential aspect toward the construction of a practical spectrochemical analysis model for biological analysis in real-world applications, where fast, accurate and reliable classification models are fundamental

Socioeconomic inequalities in dental health services in Sao Paulo, Brazil, 2003–2008

Abstract\ud \ud Background\ud Access to, and use of, dental health services in Brazil have improved since 2003. The increase of private health care plans and the implementation of the “Smiling Brazil” Program, the largest public oral health care program in the world, could have influenced this increase in access. However, we do not yet know if inequalities in the use of dental health services persist after the improvement in access. The aims of this study are to analyze socioeconomic differences for dental health service use between 2003 and 2008 in São Paulo and to examine changes in these associations since the implementation of the Smiling Brazil program in 2003.\ud \ud \ud Method\ud Data was obtained via two household health surveys (ISA-Capital 2003 and ISA-Capital 2008) which investigated living conditions, lifestyle, health status and use of health care services. Logistic regression was used to analyze associations between socioeconomic factors and dental services use. Additionally, trends from 2003 to 2008 regarding socioeconomic characteristics and dental health service use were explored.\ud \ud \ud Results\ud Overall, dental health service use increased between 2003 and 2008 and was at both time points more common among those who had higher income, better education, better housing conditions, private health care plans and were Caucasian. Inequalities in use of dental health care did not decrease over time. Among the reasons for not seeking dental care, not having teeth and financial difficulty were more common in lower socioeconomic groups, while thinking it was unnecessary was more common in higher socioeconomic groups.\ud \ud \ud Conclusions\ud The Brazilian oral health policy is still in a period of expansion and seems to have contributed slightly to increased dental health service use, but has not influenced socioeconomic inequalities in the use of these services. Acquiring deeper knowledge about inequalities in dental health service use will contribute to better understanding of potential barriers to reducing them.São Paulo Research Foundation-FAPESP. Process 2012/214153-0 and\ud 2013/26687-2.\ud National Council for Scientific and Technological Development (CNPq).\ud The surveys were financed by the Municipal Health Secretary of São Paulo.\ud Researchers from three universities in São Paulo state (University of Sao\ud Paulo, University of Campinas and University of the State of São Paulo)\ud participated in administering the surveys

Constructing public oral health policies in Brazil: issues for reflection

This paper addresses the construction of public oral health policies in Brazil by reviewing the available literature. It includes a discussion of the social responses given by the Brazilian State to oral health policies and the relationship of these responses with the ideological oral health movements that have developed globally, and that have specifically influenced oral health policies in Brazil. The influence of these movements has affected a series of hegemonic practices originating from both Market Dentistry and Preventive and Social Dentistry in Brazil. Among the state activities that have been set into motion, the following stand out: the drafting of a law to regulate the fluoridation of the public water supply, and the fluoridation of commercial toothpaste in Brazil; epidemiological surveys to analyze the status of the Brazilian population's oral health; the inclusion of oral health in the Family Health Strategy (Estratégia de Saúde da Família - ESF); the drawing up of the National Oral Health Policy, Smiling Brazil (Brasil Sorridente). From the literature consulted, the progressive expansion of state intervention in oral health policies is observed. However, there remains a preponderance of hegemonic "dental" practices reproduced in the Unified Public Health Service (Sistema Único de Saúde - SUS) and the Family Health Strategy

Aquisição fonológica de crianças de classe sócio econômica alta Phonological acquisition in socio-economical high-class children

OBJETIVO: investigar a aquisição fonológica em uma população de crianças com desenvolvimento normal. MÉTODOS: foram avaliadas 240 crianças, de ambos os sexos, com idades entre três e oito anos. Foram realizadas análises relativas ao inventário fonético e percentual de consoantes corretas. Os dados foram analisados em relação à faixa etária e sexo. RESULTADOS: aos três anos de idade os fonemas /p/, /b/, /t/, /d/, /k/, /g/, /m/, e /n/ já estão adquiridos e estabilizados no sistema fonológico das crianças. Os fonemas /f/, /v/, /s/, /&#643;/,/z/, /&#658;/, /&#654;/e/&#626;/ e as africadas [t&#643;]e[d&#658;]também são adquiridos nesta faixa etária apesar de ter sido encontrada uma grande variabilidade de produção entre as crianças. A aquisição do fonema /&#638;/ ocorre inicialmente na posição de onset simples (quatro anos) e posteriormente na posição de onset complexo (cinco anos), a aquisição do fonema /l/ em onset simples ocorre aos três anos e em onset complexo aos quatro anos e o fonema /R/ em onset simples é adquirido na faixa etária de três anos e na posição de coda aos quatro anos. CONCLUSÃO: desde a faixa etária de três anos, muitas crianças possuem o inventário fonético completo havendo, porém, uma grande variabilidade entre as crianças. Com relação ao PCC e ao PCC-R, concluiu-se que a média do percentual de consoantes corretas tem um crescimento significativo e gradual de acordo com o aumento da faixa etária. Em relação à variável sexo, não foi observada nenhuma diferença estatisticamente significante em nenhuma das análises realizadas nesta pesquisa.<br>PURPOSE: to investigate phonological acquisition in population of children with normal development. METHODS: the participants of this study were 240 children of both genders, between 3 and 8-year old. Data were analyzed with respect to age and gender. RESULTS: the results allow to conclude that at the age of 3 the phonemes /p/, /b/, /t/, /d/, /k/, /g/, /m/, and /n/ are already acquired and stabilized in the phonological system of the children. Also the phonemes /f/, /v/, /s/, /&#643;/, /z/, /&#658;/, /&#654;/ and /&#626;/ and the affricates [t&#643;]e[d&#658;] are already acquired at that age although we found a great production variability between children. The acquisition of the phoneme /&#638;/ occurs initially in simple onset (age 4) and afterwards in complex onset (age 5), the acquisition of the phoneme /l/ in simple onset occurs at age 3 and in complex onset at age 4 and the phoneme /R/ in simple onset is acquired at age of 3 and in final position at the age of 4. CONCLUSION: as for the total number of phonemes acquired, it can be concluded that from the age of 3 many children have a complete phonetic inventory, there is a great variability among children. As far as PCC and PCC-R is concerned, the mean percentage of correct consonants increases significantly and gradually while age increases. With regard to gender, not a single significant difference was found for any of the analyses performed in the current study