This is an initial study using infrared (IR) in silico data as a standard database in preliminary method for new synthetic seized drugs. For this purpose, ten of the most common synthetic illicit seized substances on the Brazilian market were compared and computational chemistry was used as a tool for theoretical standard database. Infrared data from standard electronic library, experimental data from seized samples and data simulated by Density Functional Theory (DFT) were evaluated. The feasibility of the method was based on the degree of correlation of evaluated data. The results suggest that the computational methodology can be a viable way to analyze the structures of new synthetic drugs and obtain preliminary infrared profiles. Correlations data indicated a presumptive identification of the analyzed samples and it was also possible to observe a preliminary identification of drugs in five classes. However, it was observed that some synthetic cathinones and phenylethylamines were confused with amphetamines. Therefore, new studies must be developed to optimize the use of these data, because the simulated IR spectra can be advantageous to evaluate the profile of possible substances that may be synthesized in the future. (IR purpose library DFT (DFT profiles classes However amphetamines Therefore future

Chemically modified imidazole molecules: 4-(1H-imidazol-1-yl)aniline, 4-(1H-imidazol-1-yl)benzaldehyde, 4-(1H-imidazol-1-yl)phenol and (4-(1H-imidazol-1-yl)phenyl)methanol were investigated as inhibitors of the copper (Cu0) corrosion in 0.5 mol L-1 H2SO4 medium. The electrochemical corrosion data were obtained by monitoring open circuit potential, linear potentiodynamic polarization and electrochemical impedance spectroscopy techniques, while the computational density functional theory (DFT) method was applied to correlate the electronic properties of the molecules with corrosion inhibition efficiencies. All molecules had inhibited the Cu corrosion, and the inhibition values lied between 80 and 94%. A good correlation between the inhibition efficiencies values and Gibbs adsorption energy was found, showing that the more negative Gibbs energy, better interaction between the corrosion inhibitor with the Cu0 surface, diminishing its corrosion in 0.5 mol L-1 H2SO4 medium. The DFT calculations showed significative differences in electronic and reactivity properties of imidazole and other molecules. The higher corrosion inhibition of imidazole derivates could be explained by electrophilic characteristic of these molecules, since there are empty molecular orbitals spread over mainly in benzene rings that make a metal-ligand charge transfer, receiving electronic density from the copper surface by backbonding, according to the electronic Fukui functions and the potential charge distribution considering the map of electrostatic potential.

RESUMO OBJETIVO Analisar a associação entre fatores de risco comportamentais modificáveis para doenças não transmissíveis e parâmetros do sono em adolescentes brasileiros. MÉTODOS Estudo transversal que utilizou dados do Consórcio de Coortes RPS, São Luís, Brasil para o seguimento de adolescentes de 18-19 anos (n = 2.515). Os desfechos foram a sonolência diurna excessiva (Escala de Sonolência de Epworth – ESE) e a qualidade do sono (Índice de Qualidade do Sono de Pittsburgh – IQSP). As exposições de interesse foram os fatores de risco comportamentais para doenças não transmissíveis (DNT): tempo de tela, inatividade física, álcool, cigarro, drogas ilícitas, consumo de cafeína, consumo de bebidas adoçadas com açúcar. O excesso de peso foi considerado um possível mediador dessa associação entre as exposições de interesse e os desfechos. Os modelos foram analisados por modelagem com equações estruturais. RESULTADOS A inatividade física (Coeficiente padronizado, CP = 0,112; p = 0,001), maior consumo de álcool (CP = 0,168; p = 0,019) e de bebidas adoçadas com açúcar (CP = 0,128; p < 0,001) foram associados a sonolência diurna excessiva nos adolescentes; a melhor situação socioeconômica também foi associada a este desfecho (CP = 0,128; p < 0,001). A inatividade física (CP = 0,147; p < 0,001) e o maior consumo de bebidas adoçadas com açúcar (CP = 0,089; p = 0,003) também se associaram com a qualidade do sono ruim. O excesso de peso não foi mediador e nem associado à qualidade do sono ou à sonolência diurna excessiva. CONCLUSÕES Os principais fatores de risco comportamentais modificáveis para DNT estão associados a piores parâmetros do sono já na adolescência; alertando para um quadro de acúmulos de riscos para distúrbios de sono no futuro.

ABSTRACT OBJECTIVE To analyze the association between modifiable behavioral risk factors for non-communicable diseases and sleep parameters in Brazilian adolescents. METHODS This was a cross-sectional study that used data from the RPS Cohort Consortium, São Luís, Brazil for the follow-up of adolescents aged 18–19 years (n = 2,515). The outcomes were excessive daytime sleepiness (Epworth Sleepiness Scale – ESS) and sleep quality (Pittsburgh Sleep Quality Index – PSQI). The exposures of interest were the behavioral risk factors for non-communicable diseases (NCDs): screen time, physical inactivity, alcohol, smoking, illicit drugs, caffeine intake, and consumption of sugar-sweetened beverages. Excess weight was considered a possible mediator of this association between the exposures of interest and the outcomes. The models were analyzed by modeling with structural equations. RESULTS Physical inactivity (standardized coefficient, SC = 0.112; p = 0.001), higher consumption of alcohol (SC = 0.168; p = 0.019) and of sugar-sweetened beverages (SC = 0.128; p < 0.001) were associated with excessive daytime sleepiness in adolescents; better socioeconomic status was also associated with this outcome (SC = 0.128; p < 0.001). Physical inactivity (SC = 0.147; p < 0.001) and higher consumption of sugar-sweetened beverages (SC = 0.089; p = 0.003) were also associated with poor sleep quality. Overweight was neither a mediator nor associated with sleep quality or excessive daytime sleepiness. CONCLUSIONS The main modifiable behavioral risk factors for NCDs are associated with worse sleep parameters already in adolescence, which serves as a warning toward the accumulation of risks for sleep disorders in the future.

ABSTRACT OBJECTIVE To analyze the association between modifiable behavioral risk factors for non-communicable diseases and sleep parameters in Brazilian adolescents. METHODS This was a cross-sectional study that used data from the RPS Cohort Consortium, São Luís, Brazil for the follow-up of adolescents aged 18–19 years (n = 2,515). The outcomes were excessive daytime sleepiness (Epworth Sleepiness Scale – ESS) and sleep quality (Pittsburgh Sleep Quality Index – PSQI). The exposures of interest were the behavioral risk factors for non-communicable diseases (NCDs): screen time, physical inactivity, alcohol, smoking, illicit drugs, caffeine intake, and consumption of sugar-sweetened beverages. Excess weight was considered a possible mediator of this association between the exposures of interest and the outcomes. The models were analyzed by modeling with structural equations. RESULTS Physical inactivity (standardized coefficient, SC = 0.112; p = 0.001), higher consumption of alcohol (SC = 0.168; p = 0.019) and of sugar-sweetened beverages (SC = 0.128; p < 0.001) were associated with excessive daytime sleepiness in adolescents; better socioeconomic status was also associated with this outcome (SC = 0.128; p < 0.001). Physical inactivity (SC = 0.147; p < 0.001) and higher consumption of sugar-sweetened beverages (SC = 0.089; p = 0.003) were also associated with poor sleep quality. Overweight was neither a mediator nor associated with sleep quality or excessive daytime sleepiness. CONCLUSIONS The main modifiable behavioral risk factors for NCDs are associated with worse sleep parameters already in adolescence, which serves as a warning toward the accumulation of risks for sleep disorders in the future.

RESUMO OBJETIVO Analisar a associação entre fatores de risco comportamentais modificáveis para doenças não transmissíveis e parâmetros do sono em adolescentes brasileiros. MÉTODOS Estudo transversal que utilizou dados do Consórcio de Coortes RPS, São Luís, Brasil para o seguimento de adolescentes de 18-19 anos (n = 2.515). Os desfechos foram a sonolência diurna excessiva (Escala de Sonolência de Epworth – ESE) e a qualidade do sono (Índice de Qualidade do Sono de Pittsburgh – IQSP). As exposições de interesse foram os fatores de risco comportamentais para doenças não transmissíveis (DNT): tempo de tela, inatividade física, álcool, cigarro, drogas ilícitas, consumo de cafeína, consumo de bebidas adoçadas com açúcar. O excesso de peso foi considerado um possível mediador dessa associação entre as exposições de interesse e os desfechos. Os modelos foram analisados por modelagem com equações estruturais. RESULTADOS A inatividade física (Coeficiente padronizado, CP = 0,112; p = 0,001), maior consumo de álcool (CP = 0,168; p = 0,019) e de bebidas adoçadas com açúcar (CP = 0,128; p < 0,001) foram associados a sonolência diurna excessiva nos adolescentes; a melhor situação socioeconômica também foi associada a este desfecho (CP = 0,128; p < 0,001). A inatividade física (CP = 0,147; p < 0,001) e o maior consumo de bebidas adoçadas com açúcar (CP = 0,089; p = 0,003) também se associaram com a qualidade do sono ruim. O excesso de peso não foi mediador e nem associado à qualidade do sono ou à sonolência diurna excessiva. CONCLUSÕES Os principais fatores de risco comportamentais modificáveis para DNT estão associados a piores parâmetros do sono já na adolescência; alertando para um quadro de acúmulos de riscos para distúrbios de sono no futuro.

Was supposed a numerical relationship between atoms of Hydrogen and Carbon in a hydrocarbon, assumption valid for all types of chains. In the proposed equation, variables such as number and types of carbon bonds are present, as well as the possible cycles. It was shown that the equation reduces to the known “general formulas” when applied to the type of chain in question. There is also a generalization of the equation to include elements of the group 16 (6A) of the Periodic Table, expanding its application to the molecules containing functional groups of this elements (we used functional groups containing oxygen as examples). This application generates an equation for each functional group, in an effort to study them algebraically; this effort points to the objective of the article, which is to provide algebraic foundations for the countable properties in chemical bonding. Finally, possible generalizations of the equation were mentioned, pointing out ways to be followed by those who are interested in this new subject. Even though it was done as a pure science research, it is easy to ignore non-interesting variables and introduce new interesting ones.

ABSTRACT OBJECTIVE: To analyze the effects of early determinants on adolescent fat-free mass. METHODS: A cohort study with 579 adolescents evaluated at birth and adolescence in a birth cohort in São Luís, Maranhão. In the proposed model, estimated by structural equation modeling, socioeconomic status (SES) at birth, maternal age, pregestational body mass index (BMI), gestational smoking, gestational weight gain, type of delivery, gestational age, sex of the newborn, length and weight at birth, adolescent socioeconomic status, “neither study/nor work” generation, adolescent physical activity level and alcohol consumption were tested as early determinants of adolescent fat-free mass (FFM). RESULTS: A higher pregestational BMI resulted in higher FFM in adolescence (Standardized Coefficient, SC = 0.152; p < 0.001). Being female implied a lower FFM in adolescence (SC = −0.633; p < 0.001). The negative effect of gender on FFM was direct (SC = −0.523; p < 0.001), but there was an indirect negative effect via physical activity level (SC = −0.085; p < 0.001). Women were less active (p < 0.001). An increase of 0.5 kg (1 Standard Deviation, SD) in birth weight led to a gain of 0.25 kg/m2 (0.106 SD) in adolescent FFM index (p = 0.034). Not studying or working had a negative effect on the adolescent's FFM (SC = −0.106; p = 0.015). Elevation of 1 SD in the adolescent's physical activity level represented an increase of 0.5 kg/m2 (0.207 SD) in FFM index (p < 0.001). CONCLUSIONS: The early determinants with the greatest effects on adolescent FFM are gender, adolescent physical activity level, pregestational BMI, birth weight and belonging to the “neither-nor” generation.

ABSTRACT OBJECTIVE: To analyze the effects of early determinants on adolescent fat-free mass. METHODS: A cohort study with 579 adolescents evaluated at birth and adolescence in a birth cohort in São Luís, Maranhão. In the proposed model, estimated by structural equation modeling, socioeconomic status (SES) at birth, maternal age, pregestational body mass index (BMI), gestational smoking, gestational weight gain, type of delivery, gestational age, sex of the newborn, length and weight at birth, adolescent socioeconomic status, “neither study/nor work” generation, adolescent physical activity level and alcohol consumption were tested as early determinants of adolescent fat-free mass (FFM). RESULTS: A higher pregestational BMI resulted in higher FFM in adolescence (Standardized Coefficient, SC = 0.152; p < 0.001). Being female implied a lower FFM in adolescence (SC = −0.633; p < 0.001). The negative effect of gender on FFM was direct (SC = −0.523; p < 0.001), but there was an indirect negative effect via physical activity level (SC = −0.085; p < 0.001). Women were less active (p < 0.001). An increase of 0.5 kg (1 Standard Deviation, SD) in birth weight led to a gain of 0.25 kg/m2 (0.106 SD) in adolescent FFM index (p = 0.034). Not studying or working had a negative effect on the adolescent's FFM (SC = −0.106; p = 0.015). Elevation of 1 SD in the adolescent's physical activity level represented an increase of 0.5 kg/m2 (0.207 SD) in FFM index (p < 0.001). CONCLUSIONS: The early determinants with the greatest effects on adolescent FFM are gender, adolescent physical activity level, pregestational BMI, birth weight and belonging to the “neither-nor” generation.

Abstract INTRODUCTION The Integrated Program of Leprosy Control was initiated in 2003 in the municipality of Buriticupu, Maranhão, Brazil, an area considered hyperendemic for leprosy. Here, we present the evolution of the indicators of leprosy within the established period in children aged <15 years. METHODS: This is a descriptive study based on an active search for cases and spontaneous healthcare demand for leprosy, with an evolutionary analysis of the detection coefficient of new cases. We considered individuals aged <15 years diagnosed with leprosy from January 2003 to December 2015. To evaluate the factors associated with clinical and operational forms, Chi-square, Fisher’s exact, or Fisher-Freeman-Halton tests were performed. RESULTS A total of 61 new cases were detected (6.9% of the total leprosy cases diagnosed in the municipality during the study period), and the majority was found in males (62.3%). The most frequent operational classification was paucibacillary (67.2%), and this association increased with age. The tuberculoid clinical form was the most prevalent in both sexes and in the age range of 10 to <15 years. There was a reduction in the detection coefficient from 21.84/100,000 inhabitants in 2003 to 2.79/100,000 in 2015. CONCLUSIONS Despite the progress in the control of leprosy, this historical series shows that it is necessary to strengthen educational measures and implement control actions, so that the disease ceases to be a public health problem in the population aged <15 years.

RESUMO Objetivos: avaliar a evolução dos indicadores clínicos que caracterizam a permeabilidade das vias aéreas em pacientes no pós-operatório de cirurgias toracoabdominais e analisar sua relação com a ocorrência do diagnóstico “desobstrução ineficaz das vias aéreas”. Métodos: pesquisa descritiva, quantitativa, longitudinal realizada com 60 pacientes que foram acompanhados por cinco dias consecutivos. Foram utilizados 11 indicadores do resultado de enfermagem “estado respiratório: permeabilidade das vias aéreas”. Resultados: no primeiro dia de avaliação os indicadores mais comprometidos foram: frequência respiratória, tosse, profundidade da respiração e uso de músculos acessórios. Durante o acompanhamento, verificou-se que a maior parte dos indicadores apresentou desvio leve da variação normal e, na última avaliação, houve predomínio de indicadores com algum grau de comprometimento. Conclusões: com auxílio da Classificação dos resultados de enfermagem, observou-se que pacientes submetidos a cirurgias toracoabdominais podem apresentar comprometimento da permeabilidade das vias aéreas mesmo após dias da realização do procedimento cirúrgico.

ABSTRACT Objectives: to evaluate the evolution of clinical indicators that characterize airway permeability in patients in the postoperative period of thoracoabdominal surgeries and to analyze their relationship with the occurrence of the diagnosis “ineffective airway clearance”. Methods: descriptive, quantitative, longitudinal research with 60 patients who were followed for five consecutive days. Eleven indicators of the nursing outcome “respiratory status: airway permeability” were used. Results: on the first day of evaluation, the most compromised indicators were: respiratory rate, cough, depth of breath and use of accessory muscles. During follow-up, most of the indicators presented a slight deviation from normal variation and, in the last evaluation, there was a predominance of indicators with some degree of impairment. Conclusions: with the aid of the Nursing Outcomes Classification, it was observed that patients submitted to thoracoabdominal surgeries may present compromised airway permeability even days after surgery.

RESUMEN Objetivos: valorar la evolución de los indicadores clínicos que caracterizan la permeabilidad de las vías aéreas en pacientes en el posoperatorio de cirugías toracoabdominales y evaluar su relación con la ocurrencia del diagnóstico “desobstrucción ineficaz de las vías aéreas”. Métodos: investigación descriptiva, cuantitativa, longitudinal en la cual participaron 60 pacientes que recibieron seguimiento por cinco días. Se utilizaron 11 indicadores del resultado de enfermería “estado respiratorio: permeabilidad de las vías aéreas”. Resultados: en el primer día de evaluación, los indicadores más comprometidos fueron: frecuencia respiratoria, tos, profundidad de la respiración y utilización de músculos accesorios. Durante el seguimiento, se verificó que la mayor parte de los indicadores presentó una leve desviación de la variación normal y, en la última evaluación, hubo un predominio de indicadores con algún grado de comprometimiento. Conclusiones: con la ayuda de la Clasificación de los resultados de enfermería, se observó que los pacientes sometidos a cirugías toracoabdominales pueden presentar comprometimiento de la permeabilidad de las vías aéreas incluso después de algunos días de realizar el procedimiento quirúrgico.

ABSTRACT Objectives: to evaluate the evolution of clinical indicators that characterize airway permeability in patients in the postoperative period of thoracoabdominal surgeries and to analyze their relationship with the occurrence of the diagnosis “ineffective airway clearance”. Methods: descriptive, quantitative, longitudinal research with 60 patients who were followed for five consecutive days. Eleven indicators of the nursing outcome “respiratory status: airway permeability” were used. Results: on the first day of evaluation, the most compromised indicators were: respiratory rate, cough, depth of breath and use of accessory muscles. During follow-up, most of the indicators presented a slight deviation from normal variation and, in the last evaluation, there was a predominance of indicators with some degree of impairment. Conclusions: with the aid of the Nursing Outcomes Classification, it was observed that patients submitted to thoracoabdominal surgeries may present compromised airway permeability even days after surgery.

RESUMEN Objetivos: valorar la evolución de los indicadores clínicos que caracterizan la permeabilidad de las vías aéreas en pacientes en el posoperatorio de cirugías toracoabdominales y evaluar su relación con la ocurrencia del diagnóstico “desobstrucción ineficaz de las vías aéreas”. Métodos: investigación descriptiva, cuantitativa, longitudinal en la cual participaron 60 pacientes que recibieron seguimiento por cinco días. Se utilizaron 11 indicadores del resultado de enfermería “estado respiratorio: permeabilidad de las vías aéreas”. Resultados: en el primer día de evaluación, los indicadores más comprometidos fueron: frecuencia respiratoria, tos, profundidad de la respiración y utilización de músculos accesorios. Durante el seguimiento, se verificó que la mayor parte de los indicadores presentó una leve desviación de la variación normal y, en la última evaluación, hubo un predominio de indicadores con algún grado de comprometimiento. Conclusiones: con la ayuda de la Clasificación de los resultados de enfermería, se observó que los pacientes sometidos a cirugías toracoabdominales pueden presentar comprometimiento de la permeabilidad de las vías aéreas incluso después de algunos días de realizar el procedimiento quirúrgico.

RESUMO Objetivos: avaliar a evolução dos indicadores clínicos que caracterizam a permeabilidade das vias aéreas em pacientes no pós-operatório de cirurgias toracoabdominais e analisar sua relação com a ocorrência do diagnóstico “desobstrução ineficaz das vias aéreas”. Métodos: pesquisa descritiva, quantitativa, longitudinal realizada com 60 pacientes que foram acompanhados por cinco dias consecutivos. Foram utilizados 11 indicadores do resultado de enfermagem “estado respiratório: permeabilidade das vias aéreas”. Resultados: no primeiro dia de avaliação os indicadores mais comprometidos foram: frequência respiratória, tosse, profundidade da respiração e uso de músculos acessórios. Durante o acompanhamento, verificou-se que a maior parte dos indicadores apresentou desvio leve da variação normal e, na última avaliação, houve predomínio de indicadores com algum grau de comprometimento. Conclusões: com auxílio da Classificação dos resultados de enfermagem, observou-se que pacientes submetidos a cirurgias toracoabdominais podem apresentar comprometimento da permeabilidade das vias aéreas mesmo após dias da realização do procedimento cirúrgico.

The corrosion behavior of austenitic and superaustenitic stainless steels was investigated in carbon dioxide-saturated synthetic oil field formation water using cyclic polarization tests. In order to measure the effect of carbon dioxide pressure, the samples were also exposed in a pressurized medium containing carbon dioxide and synthetic air. For this purpose, tests were performed for long exposure time at 80 °C under 8 MPa of a mixture of carbon dioxide and synthetic air both acting togethere. The results indicated that the type of corrosion on the surfaces of the samples after all the tests was pitting corrosion. According to the results, the AL-6XNPLUS™ steel presented the best performance in all experiments. The results also indicated that the conventional austenitic stainless steels are not suitable for the use in carbon dioxide containing environment in aqueous medium.

Abstract INTRODUCTION: The Integrated Program of Leprosy Control was initiated in the municipality of Buriticupu, Maranhão, Brazil, an area considered hyperendemic for leprosy in 2003. It aims at assessing the clinical and epidemiological characteristics of the disease to reduce the detection rate of new cases until 2015. Here, we present the evolution of the indicators of leprosy within the period from 2003 to 2015. METHODS: We conducted a descriptive analytical study based on the active search for and voluntary referral of cases of leprosy. The detection rate of new cases was analyzed over time. We included individuals diagnosed with leprosy between January 2003 and December 2015. The association between categorical variables was assessed using the chi-square test of independence, considering a level of significance of 5%. When the association was significant, the detection rate (with a confidence interval of 95%) was calculated. RESULTS: Overall, 879 new leprosy cases were detected; the majority of the affected individuals were men (65.9%). Multibacillary leprosy was the most common type of the disease, according to the operational classification (55.5%); it showed the strongest association with an age ≥60 years. We also detected an association between the male sex and both, lepromatous and multibacillary leprosy. The detection rate reduced from 211.09/100,000 population in 2003 to 50.26/100,000 population in 2015. CONCLUSIONS: We found an improvement in leprosy control, with a reduction in the detection rate and the absolute number of cases. Strengthening of disease control measures should be prioritized to eliminate leprosy as a public health concern in this municipality.

Resumo Objetivo: o objetivo deste trabalho é analisar o efeito da mediação da satisfação sobre a relação entre a cultura organizacional e o comprometimento no trabalho. Metodologia: Este trabalho adota uma abordagem quantitativa e descritiva com aplicação de questionário on-line a trabalhadores de um banco público de fomento com atuação no Nordeste do Brasil. O método de análise foi o uso de modelagem de equações estruturais. Resultados: Os principais resultados indicam que a satisfação no trabalho apresenta um papel importante no comprometimento, mediando a influência positiva da cultura organizacional no aumento do comprometimento no trabalho em suas dimensões afetiva, instrumental e normativa para a cultura adhocrática e do comprometimento afetivo para a cultura clã. Indicam também que a satisfação de forma direta é preditora do comprometimento organizacional da mesma forma que quando ela é mediadora entre cultura e comprometimento. Contribuição: Este trabalho contribui para ampliar o conhecimento teórico sobre as relações estabelecidas entre cultura, satisfação e comprometimento. Para a área de gestão de pessoas, esse conhecimento pode favorecer o desempenho organizacional, ao permitir aos gestores atuarem de modo mais preciso sobre cada um desses construtos.

Abstract Purpose: The objective of this study is to analyze the mediating effect of satisfaction on the relationship between organizational culture and commitment at work. Design/methodology/approach: This paper adopts a quantitative and descriptive approach, applying an online questionnaire to employees of a public development bank operating in the Northeast of Brazil. The analysis method involved the use of structural equations modeling. Findings: The main results indicate that job satisfaction plays an important role in employee commitment, mediating the positive influence of organizational culture on commitment to work in its affective, instrumental, and normative dimensions in adhocratic cultures, and on affective commitment in clan cultures. They also indicate that satisfaction is a direct predictor of organizational commitment in the same way it mediates the relationship between culture and commitment. Originality/value: This paper contributes to increasing the theoretical knowledge about the relationships established between culture, satisfaction, and commitment. For the area of people management, this knowledge can favor organizational performance, allowing managers to act more accurately in each of these constructs.

ABSTRACT OBJECTIVE To analyze the effects of maternal pre-pregnancy body mass index and weight gain during pregnancy on the baby's birth weight. METHODS We conducted a cross-sectional study with 5,024 mothers and their newborns using a Brazilian birth cohort study. In the proposed model, estimated by structural equation modeling, we tested socioeconomic status, age, marital status, pre-pregnancy body mass index, smoking habit and alcohol consumption during pregnancy, hypertension and gestational diabetes, gestational weight gain, and type of delivery as determinants of the baby's birth weight. RESULTS For a gain of 4 kg/m2 (1 Standard Deviation [SD]) in pre-pregnancy body mass index, there was a 0.126 SD increase in birth weight, corresponding to 68 grams (p < 0.001). A 6 kg increase (1 SD) in gestational weight gain represented a 0.280 SD increase in newborn weight, correponding to 151.2 grams (p < 0.001). The positive effect of pre-pregnancy body mass index on birth weight was direct (standardized coefficient [SC] = 0.202; p < 0.001), but the negative indirect effect was small (SC = -0.076, p < 0.001) and partially mediated by the lower weight gain during pregnancy (SC = -0.070, p < 0.001). The positive effect of weight gain during pregnany on birth weight was predominantly direct (SC = 0.269, p < 0.001), with a small indirect effect of cesarean delivery (SC = 0.011; p < 0.001). Women with a higher pre-pregnancy body mass index gained less weight during pregnancy (p < 0.001). CONCLUSIONS The effect of gestational weight gain on the increase in birth weight was greater than that of pre-pregnancy body mass index.

ABSTRACT OBJECTIVE To analyze the effects of maternal pre-pregnancy body mass index and weight gain during pregnancy on the baby's birth weight. METHODS We conducted a cross-sectional study with 5,024 mothers and their newborns using a Brazilian birth cohort study. In the proposed model, estimated by structural equation modeling, we tested socioeconomic status, age, marital status, pre-pregnancy body mass index, smoking habit and alcohol consumption during pregnancy, hypertension and gestational diabetes, gestational weight gain, and type of delivery as determinants of the baby's birth weight. RESULTS For a gain of 4 kg/m2 (1 Standard Deviation [SD]) in pre-pregnancy body mass index, there was a 0.126 SD increase in birth weight, corresponding to 68 grams (p < 0.001). A 6 kg increase (1 SD) in gestational weight gain represented a 0.280 SD increase in newborn weight, correponding to 151.2 grams (p < 0.001). The positive effect of pre-pregnancy body mass index on birth weight was direct (standardized coefficient [SC] = 0.202; p < 0.001), but the negative indirect effect was small (SC = -0.076, p < 0.001) and partially mediated by the lower weight gain during pregnancy (SC = -0.070, p < 0.001). The positive effect of weight gain during pregnany on birth weight was predominantly direct (SC = 0.269, p < 0.001), with a small indirect effect of cesarean delivery (SC = 0.011; p < 0.001). Women with a higher pre-pregnancy body mass index gained less weight during pregnancy (p < 0.001). CONCLUSIONS The effect of gestational weight gain on the increase in birth weight was greater than that of pre-pregnancy body mass index.