Characterization and classification of oleogels and edible oil using vibrational spectroscopy in tandem with one-class and multiclass chemometric methods.

Oleogel represents a promising healthier alternative to act as a substitute for conventional fat in various food products. Oil selection is a crucial factor in determining the technological properties and applications of oleogels due to their distinct fatty acid composition, molecular weight, and thermal properties, as well as the presence of antioxidants and oxidative stability. Hence, the relevance of monitoring oleogel properties by non-destructive, eco-friendly, portable, fast, and effective techniques is a relevant task and constitutes an advance in the evaluation of oleogels quality. Thus, the present study aims to classify oleogels rapidly and reliably, without the use of chemicals, comparing two handheld near infrared (NIR) spectrometers and one portable Raman device. Furthermore, two different multivariate methods are compared for oleogel classification according to oil type. Three types of oleogels were prepared, containing 95 % oil (sunflower, soy, olive) and 5 % beeswax as a structuring agent, melted at 90 °C. Polarized light microscopy (PLM) images were acquired, and fatty acid composition, peroxide index and free fatty acid content were determined using official methods. A total of 240 oleogel and 92 oil spectra were obtained for each instrument. After spectra pretreatment, Principal Component Analysis (PCA) was performed, and two classification methods were investigated. The Data Driven - Soft Independent Modelling of Class Analogy (DD-SIMCA) and Partial Least Squares Discriminant Analysis (PLS-DA) models demonstrated 95 % to 100 % of accuracy for the external test set. In conclusion, the use of vibrational spectroscopy using handheld and portable instruments in tandem with chemometrics showed to be an efficient alternative for classifying oils and oleogels and could be extended to other food samples. Although the classification of vegetable oils by NIR is widely used and known, this work proposes the classification of different types of oil in oleogel matrices, which has not yet been explored in the literature.

Uncovering the impact of agricultural activities and urbanization on rivers from the Piracicaba, Capivari, and Jundiaí basin in São Paulo, Brazil: A survey of pesticides, hormones, pharmaceuticals, industrial chemicals, and PFAS.

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.

Unraveling surface-enhanced Raman spectroscopy results through chemometrics and machine learning: principles, progress, and trends.

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.

Roxborough Park Community Wildfire Evacuation Drill: Data Collection and Model Benchmarking.

Wildfires are increasing in scale, frequency and longevity, and are affecting new locations as environmental conditions change. This paper presents a dataset collected during a community evacuation drill performed in Roxborough Park, Colorado (USA) in 2019. This is a wildland-urban interface community including approximately 900 homes. Data concerning several aspects of community response were collected through observations and surveys: initial population location, pre-evacuation times, route use, and arrival times at the evacuation assembly point. Data were used as inputs to benchmark two evacuation models that adopt different modelling approaches. The WUI-NITY platform and the Evacuation Management System model were applied across a range of scenarios where assumptions regarding pre-evacuation delays and the routes used were varied according to original data collection methods (and interpretation of the data generated). Results are mostly driven by the assumptions adopted for pre-evacuation time inputs. This is expected in communities with a low number of vehicles present on the road and relatively limited traffic congestion. The analysis enabled the sensitivity of the modelling approaches to different datasets to be explored, given the different modelling approaches adopted. The performance of the models were sensitive to the data employed (derived from either observations or self-reporting) and the evacuation phases addressed in them. This indicates the importance of monitoring the impact of including data in a model rather than simply on the data itself, as data affects models in different ways given the modelling methods employed. The dataset is released in open access and is deemed to be useful for future wildfire evacuation modelling calibration and validation efforts. Supplementary Information: The online version contains supplementary material available at 10.1007/s10694-023-01371-1.

Phenotypic and Genetic Components for Growth, Morphology, and Flesh-Quality Traits of Meagre (Argyrosomus regius) Reared in Tank and Sea Cage.

Meagre (Argyrosomus regius) plays an important role in the aquaculture system, with the potential for diversification of European aquaculture, and is characterized by its fast growth rate, low feed conversion ratio, and the high quality of the product. Focusing on the relevance of meagre, the aim of the study was to analyze growth performance, fish morphology, and flesh composition phenotypically and genetically to be considered as a strategy in a breeding program. For this purpose, 633 fish were raised in two different housing systems, in sea cages or in a continental tank, and when they reached harvest size, manual growth traits, automatic morphology by the image analysis program IMAFISH_ML, and flesh chemical composition (fat, protein, moisture, and collagen percentages) were measured. The fish reared in the cages showed a higher body weight and fillet fat percentage than those in the tank. Heritabilities for growth and morphology traits, and for fillet fat percentage were medium, revealing these traits as a possible selection criterion in a breeding program. Phenotypic and genetic correlations between growth and morphology traits were positive and high. Phenotypic correlations between growth or morphology traits with fillet fat percentage were positive and medium; genetic correlations were not estimated accurately.

Eastern Canada Flocks: images and manually annotated bird positions.

The Eastern Canada (ECA) Flocks data set consists of manually annotated images from the Common Eider (COEI, Somateria mollissima) Winter Survey and the Greater Snow Geese (GSGO, Anser caerulescens atlanticus) Spring Survey. The images were taken in eastern Canada using fixed-wing aircraft and manually annotated with ImageJ's Cell counter plugins. We selected and annotated the ECA Flocks images in order to test the precision of the CountEm flock size estimation method. ECA Flocks includes 179 COEI and 99 GSGO single flock images. We cut each image manually to a rectangle that excluded large parts of the image with no birds. Both versions (original and cut) of each image are available in the data set. We manually annotated 637,555 (124,309 COEI and 514,235 GSGO) bird positions in the cut images from both surveys. Each bird has an associated "Type," which refers to species and/or sex. Sex identification was only possible for adult common eiders, because females and immature males are brown birds, whereas adult males have mainly white plumage. In the COEI images 64,484 males and 58,029 females, as well as 1,796 birds of other species, were identified. In the GSGO images 504,891 Snow Geese and 9,344 birds of other species were labeled. A .csv file including all annotated bird positions and types is available for each image. The COEI and GSGO photos of the ECA Flocks data set were taken in the years 2006 and 2018 and 2016-2018, respectively. We selected these photos in order to include images with different quality and resolution. COEI and GSGO flock sizes range from 6 to 4,154 and from 43 to 36,241 respectively. There is high variability in light conditions, backgrounds, and number and spatial arrangement of birds across the images. The data set is therefore potentially useful to test the precision of methods for analyzing imagery to estimate the abundance of animals by directly detecting, identifying, and counting individuals. We release these data into the public domain under a Creative Commons Zero license waiver. When you use the data in your publication, cite this data paper. Should ECA Flocks be a major part of the data analyzed in your study, you should consider inviting the ECA Flocks originators as collaborators. If you plan to use the ECA Flocks data set, we request that you contact the ECA Flocks core team to learn whether updates are available, and whether similar analyses are already ongoing.

Surface molecularly imprinted core-shell nanoparticles and reflectance spectroscopy for direct determination of tartrazine in soft drinks.

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.

Rational Design of an Ion-Imprinted Polymer for Aqueous Methylmercury Sorption.

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.

Nasal septum deviation and inferior nasal concha bone hypertrophy in class III facial deformity / Desviación del septum nasal e hipertrofia de la concha nasal inferior en deformidad facial clase III

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.

SERS-based immunoassay for monitoring cortisol-related disorders.

As a natural response to a stressful situation, the human body produces cortisol. For this reason, cortisol is also called "the stress hormone" and is considered to be the principal stress biomarker. Although cortisol response to stress is essential for survival, abnormal levels in biological fluids may represent serious health risks. In this work, we present a cortisol biosensor which relies on a highly sensitive technique (surface-enhanced Raman spectroscopy, SERS) and a specific recognition (immunoassay). Gold nanostars were used as SERS nanotags, since they provided a better response than nanorods or nanospheres. Using the same concept, two different immunoassay modalities were evaluated, using either magnetic beads or gold-coated glass slides decorated with cortisol antibodies as the capture substrates. The magnetically-assisted SERS immunoassay presented a better performance and was therefore selected to quantify cortisol content in biological fluids (urine and serum). Significant advantages of this assay were found over standard methods such as Ultra Performance Liquid Chromatography-Mass Spectrometry (UPLC-MS) and Enzyme-Linked Immunosorbent Assay (ELISA), including higher sensitivity and repeatability, minimum sample preparation, simplicity, and portability. Therefore, the proposed SERS immunoassay might be implemented as a highly efficient tool for in situ monitoring of human stress levels and cortisol-related disorders (e.g. Cushing's syndrome and Addison's disease).

Colloidal gold clusters formation and chemometrics for direct SERS determination of bioanalytes in complex media.

In this work, we report the sensitive and selective sensing of the purine bases adenine and guanine in urine matrix by using surface-enhanced Raman spectroscopy (SERS) and a colloidal SERS substrate. To identify suitable conditions for quantitative analysis, the pH dependence of spectra of adenine, guanine, urine simulant and their mixtures was studied on gold nanoparticles suspension. Interestingly, although the urine matrix promotes the analytes signal suppression and overlapping bands, it can also cause an improvement in repeatability of the SERS measurements. This effect was associated to the relatively controlled formation of small-sized gold clusters and it was investigated both experimentally and theoretically. Furthermore, a correlation constrained multivariate curve resolution-alternating least squares (MCR-ALS) method was developed to resolve overlapping SERS bands and to quantify physiologically relevant (micromolar) concentrations of the bioanalytes. The performance of the proposed MCR-ALS approach (assessed in terms of figures of merit) was similar to that obtained by using partial least squares regression, but with the additional advantage of retrieving valuable spectral information. Therefore, this method can be used for improving selectivity of colloidal clusters in qualitative and quantitative SERS analysis of complex media, avoiding the need for tedious nanoparticle-surface modification or preliminary chromatographic separation.

Motivación autodeterminada para la actividad física y su correlación con la composición corporal en una cohorte de sujetos adultos con sobrepeso

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.

Fast discrimination of bacteria using a filter paper-based SERS platform and PLS-DA with uncertainty estimation.

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.

Correction: Simplified procedure for efficient and unbiased population size estimation.

[This corrects the article DOI: 10.1371/journal.pone.0206091.].

Simplified procedure for efficient and unbiased population size estimation.

Population size estimation is relevant to social and ecological sciences. Exhaustive manual counting, the density method and automated computer vision are some of the estimation methods that are currently used. Some of these methods may work in concrete cases but they do not provide a fast, efficient and unbiased estimation in general. Recently, the CountEm method, based on systematic sampling with a grid of quadrats, was proposed. It offers an unbiased estimation that can be applied to any population. However, choosing suitable grid parameters is sometimes cumbersome. Here we define a more intuitive grid parametrization, using initial number of quadrats and sampling fraction. A crowd counting dataset with 51 images and their corresponding, manually annotated position point patterns, are used to analyze the variation of the coefficient of error with respect to different parameter choices. Our Monte Carlo resampling results show that the error depends on the sample size and the number of nonempty quadrats, but not on the size of the target population. A procedure to choose suitable parameter values is described, and the expected coefficients of error are given. Counting about 100 particles in 30 nonempty quadrats usually yields coefficients of error below 10%.

Surface-enhanced Raman spectroscopy and MCR-ALS for the selective sensing of urinary adenosine on filter paper.

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.

Coupling of the ring-oven-based preconcentration technique and surface-enhanced Raman spectroscopy: Application for the determination of purine bases in DNA.

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.

Inclinación de incisivos maxilares en sujetos con deformidad facial de clase III: opciones en cirugía primero / Maxillary incisor inclination in subjects with class III facial deformity: options in surgery first

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.

A portable SERS method for the determination of uric acid using a paper-based substrate and multivariate curve resolution.

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.

Comparison of marginal adaptation between a monoincremental resin with sonic activation and a conventional resin / Comparación de adaptación marginal entre una resina compuesta monoincremental activada sónicamente y una resina convencional

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.