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BACKGROUND: The current techniques for determining carbon and nitrogen content to provide information about the nutritional status of plants are time-consuming and expensive. For this reason, the objective of this study was to develop an analytical method for the direct and simultaneous determination of nitrogen and carbon elemental content in soybean leaves using near-infrared spectroscopy and compare the performance of conventional (1100-2500 nm spectral range) and portable equipment (1100-1700 nm spectral range). Partial least-squares regression models were developed using 27 soybean leaf samples collected during the 2021 harvest and applied for the simultaneous determination of carbon and nitrogen in 13 samples collected during the 2022 harvest. RESULTS: The root-mean-square error of prediction values for nitrogen and carbon were low (2.42 g kg-1 and 4.37 g kg-1 respectively) for the benchtop method yielded low but higher for the portable method (3.82 g kg-1 and 10.7 g kg-1 respectively). The benchtop method did not show significant differences when compared with the reference method for determining nitrogen and carbon. In contrast, the portable methodology showed potential as a screening method for determining nitrogen levels, particularly in fieldwork. CONCLUSION: The methodologies evaluated in this study were implemented and evaluated under real crop monitoring conditions, using independent sets of calibration and prediction samples. Their utilization enables the acquisition of cost-effective, safe analytical data aligning with the principles of green analytical chemistry. © 2023 Society of Chemical Industry.
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Glycine max , Nitrogênio , Nitrogênio/análise , Carbono/análise , Folhas de Planta/química , Análise dos Mínimos Quadrados , CalibragemRESUMO
In this work, the in-tip thermal infrared enthalpimetry (in-tip TIE) method is proposed for fast enthalpimetric analysis. In this method, the reactions inside the tips of a multichannel pipette were combined with temperature monitoring by an infrared camera. The filter paper was used inside the tips to retain reagents as solutions (wetted paper mode) or as solids (dried paper mode) to perform neutralization, redox, or precipitation reactions. The dried reagents inside the tips were obtained by oven drying a solution retained in the filter paper. The determination of the total acidity of the vinegar, ascorbic acid in vitamin C tablets, and chloride in soy sauces and saline inhalation solutions was performed as examples of the application of the proposed method. The agreement with reference methods ranged from 98 to 107%. The use of reagents dried inside the tip was feasible, leading to a simple aspiration of sample solution within the 12 tips of the pipette to perform a rapid analysis (1 min). Therefore, up to 720 measurements in 1 h were feasible for in-tip TIE over up to 12 measurements for the reference methods. Moreover, miniaturization reduced reagent consumption and residue generation. For example, for in-tip TIE, only 3.6 mL of residues was generated (n = 12) over 60-240 mL in reference methods (n = 3). Contrarily to other TIE methods, no microplates or stirring was required, opening possibilities for field analysis since the multichannel pipette and the infrared camera are both operated with batteries.
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BACKGROUND: Excessive sweating is a clinical condition that can be improved with type-A botulinum toxin (BTX-A). OBJECTIVES: To evaluate and compare the largest diameter of sweating inhibition halo (SIH) of 5 different commercially available BTX-A, in five different doses, in a 6-month-long clinical evaluation. METHODS: Twenty-five adult female volunteers were injected in the dorsal trunk area with both 100 units (100UI) and 500 units (500UI) BTX-A products, reconstituted in a ratio of 1:2.5 IU, respectively. Products were applied in five different concentrations (1:2.5U, 2:5U, 3:7.5U, 4:10U, and 5:12.5U). After 30, 60, 90, 120, 150, and 180 days, a starch-iodine test was performed to obtain the largest diameter of each SIH. RESULTS: The higher the number of units used, the larger the SIH p < 0.05 for all BTX-A. However, Botox®, Botulift®, Dysport®, and Prosigne® have pretty likewise SIH along the study, with some few differences for some doses and months between one and another. However, Xeomin® is the BTX-A with the smallest SIH, in comparison with all others, in any dose and period. CONCLUSIONS: Differences were observed among all brands of BTX-As, based on dose and time after injection. Xeomin® provides the smallest SIH in comparison with others BTX-A.
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Toxinas Botulínicas Tipo A/administração & dosagem , Fármacos Neuromusculares/administração & dosagem , Sudorese/efeitos dos fármacos , Adulto , Toxinas Botulínicas Tipo A/efeitos adversos , Relação Dose-Resposta a Droga , Feminino , Voluntários Saudáveis , Humanos , Hiperidrose/tratamento farmacológico , Hiperidrose/fisiopatologia , Pessoa de Meia-Idade , Glândulas Sudoríparas/efeitos dos fármacos , Glândulas Sudoríparas/inervação , Glândulas Sudoríparas/fisiopatologia , Fatores de Tempo , Resultado do Tratamento , Adulto JovemRESUMO
Scientific advances are continually improving the knowledge of acne and contributing to the refinement of treatment options; it is important for clinicians to regularly update their practice patterns to reflect current standards. The Global Alliance to Improve Outcomes in Acne is an international group of dermatologists with an interest in acne research and education that has been meeting regularly since 2001. As a group, we have continuously evaluated the literature on acne. This supplement focuses on providing relevant clinical guidance to health care practitioners managing patients with acne, with an emphasis on areas where the evidence base may be sparse or need interpretation for daily practice.
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Acne Vulgar/tratamento farmacológico , Dermatologistas/normas , Gerenciamento Clínico , Guias de Prática Clínica como Assunto , Acne Vulgar/diagnóstico , Administração Oral , Administração Tópica , Antibacterianos/administração & dosagem , Consenso , Quimioterapia Combinada , Feminino , Humanos , Internacionalidade , Masculino , Melhoria de Qualidade , Retinoides/uso terapêutico , Medição de Risco , Índice de Gravidade de Doença , Resultado do TratamentoRESUMO
This work proposes a new methodology for the detection of discontinuities in the weld bead applied in Shielded Metal Arc Welding (SMAW) processes. The detection system is based on two sensors-a microphone and piezoelectric-that acquire acoustic emissions generated during the welding. The feature vectors extracted from the sensor dataset are used to construct classifier models. The approaches based on Artificial Neural Network (ANN) and Support Vector Machine (SVM) classifiers are able to identify with a high accuracy the three proposed weld bead classes: desirable weld bead, shrinkage cavity and burn through discontinuities. Experimental results illustrate the system's high accuracy, greater than 90% for each class. A novel Hierarchical Support Vector Machine (HSVM) structure is proposed to make feasible the use of this system in industrial environments. This approach presented 96.6% overall accuracy. Given the simplicity of the equipment involved, this system can be applied in the metal transformation industries.
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Background: Hyaluronic acid fillers are used for facial rejuvenation and are classified as non-cross-linked or cross-linked (monophasic mono- or polydensified). Objectives: To histologically assess the intradermal durability of three types of fillers (biphasic, monophasic monodensified, and monophasic polydensified), to compare the durability of the products over 6 months, and to evaluate the structural changes after application. Methods: In all, 25 volunteers received injections of three different fillers in the dermis of the right lumbar region (in one line), and equal amounts of the fillers were injected into three different sites (in the same column), yielding nine points of application in each patient. Each line was biopsied on days 2, 92, and 184; these skin samples were analyzed histologically, and the presence or absence of these fillers was verified by a dermatopathologist. Results: The histological analysis showed that over 182 days, the amount of the injected monophasic polydensified, monophasic monodensified, and biphasic filler products decreased by 62.5%, 25%, and 12.5%, respectively. Conclusions: The biphasic and monophasic monodensified fillers presented greater intradermal durability than did the monophasic polydensified filler at 6 months after intradermal injection.
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Técnicas Cosméticas , Preenchedores Dérmicos/química , Ácido Hialurônico/química , Rejuvenescimento , Biópsia , Preenchedores Dérmicos/administração & dosagem , Módulo de Elasticidade , Feminino , Humanos , Ácido Hialurônico/administração & dosagem , Injeções Intradérmicas , Pessoa de Meia-Idade , Estudos Prospectivos , Pele/anatomia & histologia , ViscosidadeRESUMO
This research aimed at developing the Trophic Water Quality Index (TWQI) for subtropical temperate Brazilian lotic systems based on a review of the indicative values of diatom species obtained using multivariate analysis techniques and considering the environmental gradient defined by a series of measured physical, chemical, and microbiological variables. Sampling was conducted from 2005 to 2009 in the Pardo River Hydrographic Basin, Rio Grande do Sul (RS), Brazil, and in the Andreas Stream Hydrographic Basin, RS, from 2012 to 2013. A total of 140 biological samples and 211 abiotic samples were collected. Data were analyzed by cluster analysis based on the Ward method and canonical correspondence analysis (CCA). The results indicated that total phosphate, turbidity, ammonia nitrogen, electrical conductivity, dissolved oxygen, and thermotolerant coliforms showed a significant correlation with the sample ordination made by CCA, in relation to a gradient of eutrophication. Eutrophication was operationally defined in a broad sense, including the problem of organic pollution and eutrophication of the water. The determination of the different tolerance degrees to eutrophication of the diatom taxa was used to assign trophic values of 1, 2.5, and 4 to species, corresponding to levels of low, medium, and high tolerance, respectively. By using the trophic values obtained for each diatom species, the TWQI constituted a new technological tool for environmental monitoring studies and showed a consistent, robust, and objective database for water quality assessment in subtropical temperate Brazilian lotic systems.
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Eutrofização , Poluição da Água/estatística & dados numéricos , Qualidade da Água/normas , Brasil , Diatomáceas/classificação , Monitoramento Ambiental/métodos , Análise Multivariada , RiosRESUMO
The main objective of this study was to use infrared spectroscopy to identify vegetable oils used as raw material for biodiesel production and apply multivariate analysis to the data. Six different vegetable oil sources--canola, cotton, corn, palm, sunflower and soybeans--were used to produce biodiesel batches. The spectra were acquired by Fourier transform infrared spectroscopy using a universal attenuated total reflectance sensor (FTIR-UATR). For the multivariate analysis principal component analysis (PCA), hierarchical cluster analysis (HCA), interval principal component analysis (iPCA) and soft independent modeling of class analogy (SIMCA) were used. The results indicate that is possible to develop a methodology to identify vegetable oils used as raw material in the production of biodiesel by FTIR-UATR applying multivariate analysis. It was also observed that the iPCA found the best spectral range for separation of biodiesel batches using FTIR-UATR data, and with this result, the SIMCA method classified 100% of the soybean biodiesel samples.
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Biocombustíveis/análise , Óleos de Plantas/análise , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Análise por Conglomerados , Análise Multivariada , Análise de Componente Principal , Padrões de ReferênciaRESUMO
Analysis of digital images by smartphone was used for copper quantification in sugarcane spirit (cachaça) samples through the formation of blue complex between copper and cuprizone. An experimental design was carried out to evaluate the best complexation reaction conditions. Moreover, different image acquisition procedures (external camera coupled to a smartphone or the smartphone camera) with different regions of interest sizes, distances in image acquisition, and concentration ranges of the calibration curve and the influence of processing the curve in univariate and multivariate modes, by PLS, were evaluated. The results obtained in three real samples and two spikes were compared with those of UV-Vis spectrophotometry, used as a reference method, and they show the potential of the proposed method for the accurate determination of copper. When compared to traditional techniques, the proposed method has the advantages of portability and low cost in addition to requiring a smaller amount of reagents.
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Cobre , Saccharum , Grão Comestível , Projetos de Pesquisa , SmartphoneRESUMO
BACKGROUND: French maritime pine bark (Pinus pinaster) extract (PBE), the registered trade name of which is Pycnogenol® , has been studied for its depigmenting action due to its antioxidant, anti-inflammatory, and anti-melanogenic activity. However, the mechanisms through which PBE are still not fully clear. OBJECTIVE: Evaluate the impact of PBE on four in vitro parameters closely associated with cutaneous pigmentation, including melanin synthesis, tyrosinase activity, endothelin-1 (ED1), and production of peroxisome proliferator-activated receptor α, δ, and γ (PPAR α, δ, and γ), by studying the modulation of action of ultraviolet radiation A (UVA)/ultraviolet radiation B (UVB), infrared-A (IR-A), visible light (VL), and association of UVA/UVB, IR-A, and VL (ASS). METHODS: Human melanocytes were incubated in a dry extract solution of PBE, exposed to UVA/UVB, IR-A, VL, and ASS for subsequent quantification of melanin, ED1, and PPAR α, δ, and γ. The effects of PBE on inhibition of tyrosinase activity were also performed by monophenolase activity assay. RESULTS: UVA/UVB, IR-A, VL, and ASS radiation caused significant increases in the synthesis of melanin, ED1, and PPAR α, δ, and γ when compared to baseline control. However, PBE significantly reduced the production of melanin, ED1, and PPAR α, δ, and γ, as well as reducing about 66.5% of the tyrosinase activity. CONCLUSIONS: PBE reduces in vitro melanin production by downregulating tyrosinase and reducing pigmentation-related mediators, such as ED1 and PPAR α, δ, and γ, therefore contributing to the inhibition of pathways associated with skin hyperpigmentation.
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Melaninas , Monofenol Mono-Oxigenase , Endotelina-1/metabolismo , Endotelina-1/farmacologia , Humanos , Melanócitos/metabolismo , Monofenol Mono-Oxigenase/metabolismo , Receptores Ativados por Proliferador de Peroxissomo/metabolismo , Receptores Ativados por Proliferador de Peroxissomo/farmacologia , Casca de Planta/metabolismo , Extratos Vegetais/metabolismo , Extratos Vegetais/farmacologia , Raios UltravioletaRESUMO
BACKGROUND: Androgenetic alopecia (AGA) is a common, genetically predisposed condition that begins after puberty and whose frequency increases with age; although biologically benign, AGA can impact patients both psychologically and socially, contributing to an impairment on their quality of life. OBJECTIVE: We sought to evaluate the psychological, social, and quality of life impairments inherent in women with AGA using 5% minoxidil daily for at least six months. DESIGN: Thirty-one women with diffuse central hair thinning and shaft miniaturization who were using 5% minoxidil daily for at least six months responded to a clinical questionnaire and underwent trichoscopy. RESULTS: 83.9 percent (n=26) of the participants reported they were satisfied with the 5% minoxidil treatment and its convenience. Hair loss influenced social life in 54.8 percent (n=17) of the respondents and choice of hair cut/hairstyle in 87.1 percent (n=27) of respondents. For 51.6 percent (n=16) hair loss was slightly increased, although it did not increase after beginning treatment. A frontoparietal pattern (74.2%, n=23), very low capillary density (61.3%, n=19), trichodynia (32.3%, n=10), and negative traction test (100%, n=31) were also observed. Miniaturization occurred in 100 percent (n=31) of patients, frontal/occipital hair thickness was reduced in 83.9 percent (n=26), and more than 10 percent of velus hair in the frontal area was observed in 83.9 percent (n=26) of patients. The number of hair shafts per follicular unit was reduced in 67.7 percent (n=21), and a higher frontal to occipital ratio of follicular units with one hair shaft was seen in 74.2 percent (n=23) of patients. Empty follicles, large numbers of peripillar brownish halo, scalp pigmentation, mild Ludwig's baldness degree, and quality of life scores of 4±3.5 points were observed. CONCLUSION: Our results indicate that patient satisfaction and quality of life of women with AGA on 5% topical minoxidil are high, although hair loss influences daily habits and social life.
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The authors wish to make the following corrections to this paper [...].
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BACKGROUND: Facial filling based on hyaluronic acid (HA) is an esthetic procedure that is widely performed worldwide. METHODOLOGY: Fifty patients underwent facial filling based on HA, and 10 board-certified dermatologists evaluated clinical photographs before and after the procedure and completed a questionnaire to provide information about the procedure. RESULTS: All doctors and 96% of patients were agreed about the pre- and postprocedural photographs. Physicians were more aware of the possibility of frequent pain and erythema. Both groups showed agreement in their responses on the following topics: the possibility of hematoma and edema, a lack of secretion, improvement in patients' self-confidence, recognition of the procedure by third parties, and knowledge of the procedure by the dermatologists themselves. However, physicians tend to overestimate the possibility of erythema, pain, and edema; they also tend to minimize the duration and discomfort of postprocedural edema and the risk of third parties noticing patients' HA filling and how much it bothers patients when third parties do notice. CONCLUSION: Doctors and patients disagree on some questions about what actually happens and what is supposed to happen in facial filling procedures based on HA.
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Técnicas Cosméticas , Médicos , Técnicas Cosméticas/efeitos adversos , Humanos , Ácido Hialurônico , Satisfação do Paciente , AutoimagemRESUMO
A method for determination of propranolol hydrochloride in pharmaceutical preparation using near infrared spectrometry with fiber optic probe (FTNIR/PROBE) and combined with chemometric methods was developed. Calibration models were developed using two variable selection models: interval partial least squares (iPLS) and synergy interval partial least squares (siPLS). The treatments based on the mean centered data and multiplicative scatter correction (MSC) were selected for models construction. A root mean square error of prediction (RMSEP) of 8.2 mg g(-1) was achieved using siPLS (s2i20PLS) algorithm with spectra divided into 20 intervals and combination of 2 intervals (8501 to 8801 and 5201 to 5501 cm(-1)). Results obtained by the proposed method were compared with those using the pharmacopoeia reference method and significant difference was not observed. Therefore, proposed method allowed a fast, precise, and accurate determination of propranolol hydrochloride in pharmaceutical preparations. Furthermore, it is possible to carry out on-line analysis of this active principle in pharmaceutical formulations with use of fiber optic probe.