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Rivers in Southeast Brazil are essential as sources of drinking water, energy production, irrigation, and industrial processes. The Piracicaba, Capivari, and Jundiaí rivers basin, known as the PCJ basin, comprises major cities, industrial hubs, and large agricultural areas, which have impacted the water quality in the region. Emerging contaminants such as pesticides, hormones, pharmaceuticals, industrial chemicals, and per- and polyfluoroalkyl substances (PFAS) are likely to be released into the rivers in the PCJ basin; however, the current Brazilian legislation does not require monitoring of most of these chemicals. Thus, the extent of emerging contaminants pollution and their risks to aquatic and human life in the basin are largely unknown. In this study, we investigated the occurrence of several pesticides, hormones, pharmaceuticals, and personal care products in 15 sampling points across the PCJ basin, while industrial chemicals and PFAS were assessed in 11 sampling points. The results show that agriculture and industrial activities are indeed causing the pollution of most rivers. Multivariate analysis indicates that some sampling points, such as Jundiaí, Capivari, and Piracicaba rivers, are largely impacted by pesticides used in agriculture. In addition, to the best of our knowledge, this is the first study reporting the presence of PFAS in rivers in São Paulo, the most populous state in Brazil. Four out of eight species of PFAS assessed in our study were detected in at least 5 sampling points at concentrations ranging from 2.0 to 50.0 ng L-1. The preliminary risk assessment indicates that various pesticides, caffeine, industrial chemicals, and PFAS were present at concentrations that could threaten aquatic life. Notably, risk quotients of 414, 340, and 178 were obtained for diuron, atrazine, and imidacloprid, respectively, in the Jundiaí River. Our study suggests that establishing a comprehensive monitoring program is needed to ensure the protection of aquatic life and human health.

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Surface-enhanced Raman spectroscopy (SERS) has gained increasing attention because it provides rich chemical information and high sensitivity, being applicable in many scientific fields including medical diagnosis, forensic analysis, food control, and microbiology. Although SERS is often limited by the lack of selectivity in the analysis of samples with complex matrices, the use of multivariate statistics and mathematical tools has been demonstrated to be an efficient strategy to circumvent this issue. Importantly, since the rapid development of artificial intelligence has been promoting the implementation of a wide variety of advanced multivariate methods in SERS, a discussion about the extent of their synergy and possible standardization becomes necessary. This critical review comprises the principles, advantages, and limitations of coupling SERS with chemometrics and machine learning for both qualitative and quantitative analytical applications. Recent advances and trends in combining SERS with uncommonly used but powerful data analysis tools are also discussed. Finally, a section on benchmarking and tips for selecting the suitable chemometric/machine learning method is included. We believe this will help to move SERS from an alternative detection strategy to a general analytical technique for real-life applications.

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The present work shows the synergistic application of reflectance spectroscopy and core-shell molecularly imprinted polymer (MIP) for rapid quantification of tartrazine in soft drinks. Studies evaluated the performance of the MIPs synthesized in the presence of silica nanoparticles unfunctionalized and functionalized with [3-(methacryloyloxy)propyl]trimethoxysilane. Although the use of functionalized silica nanoparticles promoted the highest adsorption capability of tartrazine, the material was found to be less selective when it was applied in real samples. Interestingly, the most accurate results were obtained via the application of the MIP synthesized in the presence of unfunctionalized silica nanoparticles (SiO2@MIP). The optimized core-shell MIP was also characterized by Raman spectroscopy and scanning electron microscopy. The use of direct reflectance spectroscopy in the analyte detection strategy after the template extraction from the MIPs resulted in faster and more accurate results than conventional UV-Visible spectroscopy. With regard to the analysis of the soft drink samples, no significant differences were found between the results obtained from the proposed reflectance spectroscopy-based technique and those obtained from the comparative high-performance liquid chromatography technique. Under optimized conditions, this method displayed a linear range of 1.0-12.5 µmol L-1 with LOD and LOQ values of 0.303 and 1.0 µmol L-1, respectively. The selectivity factor (ß) ranged between 1.4 up to 264 showed better recognition of tartrazine in front of other dyes. Based on the results obtained, the proposed method is found to be suitable for rapid determination of tartrazine in food samples with complex matrices without the need of applying tedious sample preparation and cost-demanding instruments.

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Methylmercury (MeHg+) is a mercury species that is very toxic for humans, and its monitoring and sorption from environmental samples of water are a public health concern. In this work, a combination of theory and experiment was used to rationally synthesize an ion-imprinted polymer (IIP) with the aim of the extraction of MeHg+ from samples of water. Interactions among MeHg+ and possible reaction components in the pre-polymerization stage were studied by computational simulation using density functional theory. Accordingly, 2-mercaptobenzimidazole (MBI) and 2-mercaptobenzothiazole (MBT), acrylic acid (AA) and ethanol were predicted as excellent sulfhydryl ligands, a functional monomer and porogenic solvent, respectively. Characterization studies by scanning electron microscopy (SEM) and Brunauer-Emmett-Teller (BET) revealed the obtention of porous materials with specific surface areas of 11 m2 g-1 (IIP-MBI-AA) and 5.3 m2 g-1 (IIP-MBT-AA). Under optimized conditions, the maximum adsorption capacities were 157 µg g-1 (for IIP-MBI-AA) and 457 µg g-1 (for IIP-MBT-AA). The IIP-MBT-AA was selected for further experiments and application, and the selectivity coefficients were MeHg+/Hg2+ (0.86), MeHg+/Cd2+ (260), MeHg+/Pb2+ (288) and MeHg+/Zn2+ (1510), highlighting the material's high affinity for MeHg+. The IIP was successfully applied to the sorption of MeHg+ in river and tap water samples at environmentally relevant concentrations.

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SUMMARY: The aim of this research was to analyze the morphology of the nasal septum and inferior nasal concha bone in class III facial deformities prior to orthodontic treatment in orthognathic surgery candidates. 40 subjects were included in this research. The inclusion criteria were an Angle class III, negative overjet and SNA angle less than 80º. Patients with facial asymmetry, facial trauma or who had undergone maxillofacial or ENT procedures were excluded. CBCT images were obtained for all the patients and the nasal septum deviation, morphology of inferior nasal concha bone and ostium of the maxillary sinus were analyzed and related to the complexity of the facial deformity expressed by the ANB angle and dental relations. The measurement was standardized by ICC and the data was analyzed using a chi square test and Spearman's coefficient with a p value < 0.005 for statistical significance. Nasal septal deviation was observed in 77.5 %. The deviation angle was 13.28º (±4.68º) and the distance from the midline to the most deviated septum was 5.56 mm (±1.8 mm) with no statistical relation to the complexity of the facial deformity. The deviated nasal septum showed inferior nasal concha bone hypertrophy on the concave side of the nasal septum deviation (p=0.049). The open or closed condition of the maxillary sinus ostium was not related to any conditions in the septum or complexity of the facial deformity. Inferior nasal concha bone hypertrophy could be related to nasal septal deviation. The nasal condition in a class III facial deformity could not differ from the general population; careful in orthognathic surgery as to be assume in the Le Fort I Osteotomy and nasal approach related to nasal septum deviation and inferior nasal concha bone.

RESUMEN: El objetivo de esta investigación fue analizar la morfología del septum y la concha nasal inferior en sujetos con deformidad facial clase III previo al tratamiento de ortodoncia preparatorio para cirugía ortognática. Fueron incluidos 40 sujetos en esta investigación. Los criterios de inclusión fueron la de presentar una clase III de Angle, overjet negativo y ángulo SNA menor que 80º. Sujetos con asimetría facial, trauma facial o quienes presentaron algún tipo de procedimiento maxilofacial o de otorrinolaringología fueron excluidos. Tomografía computadorizada cone beam (CBCT) fueron obtenidas para todos los sujetos donde le morfología del septum nasal, morfología de la concha nasal inferior y el ostium del seno maxilar fueron analizados y relacionados con la complejidad de la deformidad facial expresada como ángulo ANB y relaciones dentales. Las medidas fueron estandarizadas por el ICC y los datos fueron analizados utilizando la prueba chi cuadrado y coeficiente de Spearman con un valor de p<0,05 para obtener relaciones significativas. La desviación del septum nasal se observó en el 77,5 %; el ángulo de desvío fue de 13,28º (±4,68º) y la distancia de desvío del septum desde la línea media fue de 5,56 mm (±1,8 mm) sin diferencias estadísticas en relación a la complejidad de la deformidad. El desvío de septum nasal demostró hipertrofia de la concha nsal inferior en el lado cóncavo del septum desviado (p=0,049). La condición de ostium abierto o cerrado no fue relacionado con ninguna condición del septum nasal o complejidad de la deformidad facial. La hipertrofia de la concha nasal inferior se relacionó con el desvío de septum nasal. La condición nasal en deformidad facial de clase III no es diferente de la observada en la población general; cuidados deben ser realizados en cirugía ortognática para el desarrollo de la osteotomía de Le Fort I y aproximación nasal en relación al desvío de septum y probable alteración de la concha nasal inferior.

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Introducción. La motivación conduce a las personas a ejecutar acciones en pro de alcanzar una meta u objetivo. Este estudio buscó examinar la correlación entre la motivación autodeterminada para la actividad física y la composición corporal, en una cohorte de sujetos adultos con sobrepeso. Métodos. Se utilizó la herramienta BREQ 2 de autoinforme y para la antropometría fue medida por un técnico ISAK 1 y la composición corporal con báscula Tanita BC 420. Resultados. 46% (n = 18) de los participantes eran mujeres y 54% (n = 21) hombres. Edad promedio 31 ± 11 años, IMC: 25 ± 3 kg/m2, masa muscular 49 ± 9%, masa grasa 27 ± 16%, circunferencia de cintura (CC) 80 ± 7cm, cadera 98 ± 6cm, ICC 0,8 ± 0,05 cm. Conclusión. Se observó una correlación negativa entre variables antropométricas como IMC e ICC con el índice de autodeterminación en mujeres (r = -1 p < 0,05). La evaluación de la motivación autodeterminada debe ser la base para la programación de actividad física en población con sobrepeso.

Introduction: Motivation leads people to carry out actions in order to achieve a goal or objective. This study tried to examine the correlation between self-determined motivation for physical activity and physical composition, in a cohort of overweight adults. Method: We used the tool BREW 2 of self-report and anthopometry was measured with an ISAK 1 techinician. Body composition was measured with a Tanita BC 420 scale. Results: 46% (n=18) of patients were women and 54% (n=21) were men. The average age was 31 ±, MMI: 25 ± 3 kg/m2, muscular mass 49 ± 9%, fat, 27 ± 16%, waist circumference 80 ± 7cm, hip 98 ± 6cm, CCI 0.8 ± 0.05 cm. Conclusions: we observed a negative correlation among anthropometric variables, such as MMI and CCI with the rate of self-determination in women. Evaluating the self-determined motivation must be the base to program any physical activity in an overweight population.

Introdução: a motivação leva as pessoas a agirem em prol de atingir uma meta. Nesse sentido, este estudo tem o objetivo de analisar a correlação entre a motivacão autodeterminada para a atividade física e a composição corporal, em um grupo de sujeitos adultos com obesidade. Métodos: foi utilizada a ferramenta BREQ 2 de autorrelato; a antropometria foi medida por um técnico ISAK 1, e a composição corporal, com báscula Tanita BC 420. Resultados: 46% (n = 18) dos participantes eram mulheres e 54% (n = 21), homens. A idade média foi de 31 ± 11 anos, IMC: 25 ± 3 kg/m2; massa muscular 49 ± 9%; massa gorda 27 ± 16%; circunferencia de cintura (CC) 80 ± 7cm; quadril 98 ± 6cm, ICC 0,8 ± 0,05 cm. Conclusões: foi observada correlação negativa entre variáveis antropométricas como IMC e ICC com o índice de autodeterminação em mulheres (r = -1 p < 0,05). A avaliação da motivacão autodeterminada deve ser a base para programar atividades físicas em população com obesidade.

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Rapid and reliable identification of bacteria is an important issue in food, medical, forensic, and environmental sciences; however, conventional procedures are time-consuming and often require extensive financial and human resources. Herein, we present a label-free method for bacterial discrimination using surface-enhanced Raman spectroscopy (SERS) and partial least squares discriminant analysis (PLS-DA). Filter paper decorated with gold nanoparticles was fabricated by the dip-coating method and it was utilized as a flexible and highly efficient SERS substrate. Suspensions of bacterial samples from three genera and six species were directly deposited on the filter paper-based SERS substrates before measurements. PLS-DA was successfully employed as a multivariate supervised model to classify and identify bacteria with efficiency, sensitivity, and specificity rates of 100% for all test samples. Variable importance in projection was associated with the presence/absence of some purine metabolites, whereas confidence intervals for each sample in the PLS-DA model were calculated using a resampling bootstrap procedure. Additionally, a potential new species of bacteria was analyzed by the proposed method and the result was in agreement with that obtained via 16S rRNA gene sequence analysis, thereby indicating that the SERS/PLS-DA approach has the potential to be a valuable tool for the discovery of novel bacteria. Graphical abstract This paper describes the discrimination of bacteria at the genus and species levels, after minimal sample preparation, using paper-based SERS substrates and PLS-DA with uncertainty estimation.

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Introducción. La motivación conduce a las personas a ejecutar acciones en pro de alcanzar una meta u objetivo. Este estudio buscó examinar la correlación entre la motivación autodeterminada para la actividad física y la composición corporal, en una cohorte de sujetos adultos con sobrepeso. Métodos. Se utilizó la herramienta BREQ 2 de autoinforme y para la antropometría fue medida por un técnico ISAK 1 y la composición corporal con báscula Tanita BC 420. Resultados. 46 % (n = 18) de los participantes eran mujeres y 54 % (n = 21) hombres. Edad promedio 31 ± 11 años, IMC: 25 ± 3 kg/m2, masa muscular 49 ± 9 %, masa grasa 27 ± 16%, circunferencia de cintura (CC) 80 ± 7cm, cadera 98 ± 6cm, ICC 0,8 ± 0,05 cm. Conclusión. Se observó una correlación negativa entre variables antropométricas como IMC e ICC con el índice de autodeterminación en mujeres (r = -1 p < 0,05). La evaluación de la motivación autodeterminada debe ser la base para la programación de actividad física en población con sobrepeso.

Introduction. Motivation drives people to perform actions in pursuit of a goal or objective. This study sought to examine the correlation between self-determined motivation for physical activity and body composition in a cohort of overweight adult subjects. Methods. The BREQ 2 self-report tool was used and for anthropometry was measured by an ISAK 1 technician and body composition with Tanita BC 420 scale.Results. 46 % (n = 18) of the participants were female and 54 % (n = 21) were male. Mean age 31 ± 11 years, BMI: 25 ± 3 kg/m2, muscle mass 49 ± 9 %, fat mass 27 ± 16%, waist circumference (WC) 80 ± 7cm, hip 98 ± 6cm, ICC 0.8 ± 0.05 cm. Conclusion. A negative correlation was observed between anthropometric variables such as BMI and WC with the self-determination index in women (r = -1 p < 0.05). The evaluation of self-determined motivation should be the basis for physical activity programming in overweight population.

Introdução. A motivação leva os indivíduos a realizar acções em busca de uma meta ou objetivo. Este estudo procurou examinar a correlação entre a motivação autodeterminada para a atividade física e a composição corporal numa coorte de adultos com excesso de peso. Métodos. Foi utilizado o instrumento de auto-relato BREQ 2 e a antropometria foi medida por um técnico do ISAK 1 e a composição corporal pela balança Tanita BC 420. Resultados. 46 % (n = 18) dos participantes eram do sexo feminino e 54 % (n = 21) do sexo masculino. Idade média 31 ± 11 anos, IMC: 25 ± 3 kg/m2, massa muscular 49 ± 9 %, massa gorda 27 ± 16 %, perímetro da cintura (PC) 80 ± 7cm, anca 98 ± 6cm, CC 0,8 ± 0,05 cm. Conclusões. Houve uma correlação negativa entre variáveis antropométricas como IMC e CC com o índice de autodeterminação em mulheres (r = -1 p < 0,05). A avaliação da motivação autodeterminada deve ser a base para a programação da atividade física na população com excesso de peso.

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Adenosine is a purine nucleoside that is present in all human cells and is essential for regulating certain physiological activities in tissues and organs. Since adenosine is considered to be a potential cancer biomarker in urine, its determination may be crucial for the early diagnosis and non-invasive monitoring of cancer. Herein, we present a label-free method to quantify urinary adenosine using surface-enhanced Raman spectroscopy (SERS) and multivariate curve resolution-alternating least squares (MCR-ALS). Ring-oven preconcentration and direct deposition of monodisperse gold nanoparticles on filter paper were employed to improve the sampling efficiency. Further, MCR-ALS (assessed with and without a correlation constraint), the standard addition method and pH controls were combined to compensate for the matrix effect and to address overlapping bands in the analysis of human urine samples. As a result, the proposed method showed to be sensitive (LOD varying between 3.8 and 4.9 µmol L-1, S/R = 3), reproducible (RSD less than ±â€¯15%), and selective over other nucleosides (guanosine, cytidine, thymidine and uridine) and unknown interferences (second-order advantage). This is the first report of a SERS-chemometric method applied to urinary adenosine sensing at physiologically relevant concentrations, with minimal sample preparation, and has strong potential to be a valuable tool in cancer research.

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In this paper, we present the advantages and limitations of the coupling of a ring-oven-based preconcentration technique and surface-enhanced Raman spectroscopy (SERS). Three different methods to promote analyte adsorption on gold nanoparticles using crystal violet as a probe molecule were assessed. The results showed significant improvements in sampling process, selectivity, sensitivity, repeatability (less than ± 10%), and detection limits (nanomolar level) using a sample volume as small as 300 µL. Finally, the standard addition method was successfully applied to the quantitative SERS detection of adenine and guanine in calf thymus DNA after ring-oven preconcentration with a calculated value of (G + C)/(A + T) close to the literature value. This work could therefore pave the way to quantifying a wide variety of biologically relevant compounds in real-world samples via the use of a biodegradable, low-cost and disposable paper platform for SERS.

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El objetivo de esta investigación es determinar la inclinación de incisivos maxilares en sujetos con maloclusión de clase III. Se incluyeron 35 sujetos que presentaran deformidad facial de clase III (DF-III) para analizar la tomografía computarizada de haz cónico; las mediciones se realizaron para los cuatro incisivos maxilares identificando el plano palatino considerado entre espina nasal anterior y posterior y el eje axial dentario obtenido por la unión entre punto coronal y punto apical; los resultados mostraron angulaciones de 111,6 a 113,7 para los incisivos, lo cual permite obtener valores cercanos a la normalidad de angulación dentaria. Se concluye que los sujetos seleccionados presentan una angulación dentaria adecuada para la realización de procedimientos de cirugía primero.

The objective of this research was to determine the inclination of maxillary incisors in subjects with class III malocclusion. Were included 35 subjects with Class III facial deformity (DF-III) to analyze cone beam computed tomography; measurements were realized in the four maxillary incisors identifying the palatal plane considered between anterior and posterior nasal spine and dental axial axis from the union between coronal point and apical point; The results showed angulations from 111.6 to 113.7 for the incisors, which allows estimation of values close to normal dental angulation. It is concluded that the selected subjects present adequate dental angulation to perform surgery first.

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This paper presents a portable quantitative method for the on-site determination of uric acid in urine using surface-enhanced Raman spectroscopy (SERS) and gold nanoparticle-coated paper as a substrate. A procedure was developed for the rapid preparation of cost-effective SERS substrates that enabled the adequate control of a homogeneous active area and the use of small quantities of gold nanoparticles per substrate. The standard addition method and multivariate curve resolution-alternating least squares (MCR-ALS) were applied to compensate for the matrix effect and to address overlapping bands between uric acid and interference SERS spectra. The proposed methodology demonstrated better performance than conventional univariate methods (in terms of linearity, accuracy and precision), a wide linear range (0-3.5 mmol L(-1)) and an adequate limit of detection (0.11 mmol L(-1)). For the first time, a portable SERS method coupled with chemometrics was developed for the routine analysis of uric acid at clinically relevant concentrations with minimal sample preparation and easy extension for the on-site determination of other biomarkers in complex sample matrices.

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Abstract: aim: to determine differences in marginal adaptation between a conventional composite resin and a monoincremental resin with sonic activation. Materials and methods: 32 composite resin discs of 2.5mm in diameter and 2mm thick were fabricated in a propylene matrix and distributed in 2 groups of 16 samples each. Groups 1 FiltekTMZ350XT resin; Group 2 SonicFillTM resin with sonic activation. The gap generated between the resin and the matrix as a result of the polymerization shrinkage was analyzed in microns using a microscope at a magnification of 40X. The percentage of the lineal polymerization shrinkage was also calculated. To calculate differences in marginal adaptation between the two resins statistical analysis was performed using the unpaired t-test. Results: The extent of the gaps measured in microns and their respective standard deviations were SonicFillTM 9.95 more less 3.05 and FiltekTMZ350XT 10.21 more less5.14 (p=.86). Conclusion: The use of the monoincremental resin system with sonic activation shows a marginal adaptation similar to that of conventional resin composites, with no statistically significant differences between the studied resins.

Resumen: determinar diferencias de adaptación marginal entre una resina compuesta convencional y una resina monoincremental activada sónicamente. Material y métodos: 32 discos fabricados de resina compuesta de 2.5 mm de diámetro y 2 mm de grosor en una matriz de propileno se distribuyeron en 2 grupos de 16 muestras cada uno: grupo 1 resina FiltekTM Z350X; grupo 2 resina SonicFillTM activada sónicamente. La brecha generada entre la resina y la matriz producto de la contracción de polimerización se midió en micrones en un microscopio con magnificación 40x. Para evaluar las diferencias de adaptación marginal entre las dos resinas se realizó análisis estadístico con un t-test de muestras no pareadas. Resultados: La amplitud de las brechas medidas en micrones y sus respectivas desviaciones estándar fueron: SonicFillTM 9.95 más menos 3.05 y FiltekTM Z350X 10.21 más menos 5.14 (p=.86). Conclusión: El uso del sistema de resina monoincremental activado sónicamente presenta similar adaptación marginal que la resina convencional, no existiendo diferencias estadísticamente significativas entre las resinas estudiadas.

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Cadmium (Cd) and lead (Pb) concentrations and their relationship to the cocoa content of chocolates commercialized in Brazil were evaluated by graphite furnace atomic absorption spectrometry (GF AAS) after microwave-assisted acid digestion. Several chemical modifiers were tested during method development, and analytical parameters, including the limits of detection and quantification as well as the accuracy and precision of the overall procedure, were assessed. The study examined 30 chocolate samples, and the concentrations of Cd and Pb were in the range of <1.7-107.6 and <21-138.4 ng/g, respectively. The results indicated that dark chocolates have higher concentrations of Cd and Pb than milk and white chocolates. Furthermore, samples with five different cocoa contents (ranging from 34 to 85%) from the same brand were analyzed, and linear correlations between the cocoa content and the concentrations of Cd (R(2) = 0.907) and Pb (R(2) = 0.955) were observed. The results showed that chocolate might be a significant source of Cd and Pb ingestion, particularly for children.

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