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BACKGROUND: Metabolic syndrome increases the risk of heart disease and diabetes. Early identification and management are crucial, especially in economically challenged regions with limited healthcare access. AIMS: To develop nomograms for individualized risk estimation for metabolic syndrome in young people from low-income regions. METHODS: We assessed 496 college students from two Brazilian cities with Gini indices ≤0.56. Of these, 69.9% were female, 65.1% were younger than 20 years, 71.8% were non-white, and 64.3% were enrolled in health-related courses. For external validity, we assessed metabolic syndrome in a subset of 375 students. RESULTS: We found 10 variables associated with abdominal obesity by logistic regression: age, biological sex, physical education facilities, enrollment in sports competitions during elementary school, grade retention, physical education as the preferred subject, physical education classes per week, and enrollment in sports training in secondary school (score A); adherence to 24 h movement behaviors (B score); and body weight (score C). We designed three nomograms (for scores A, B, and C), all of which showed acceptable performance according to the area under the receiver operating characteristic curve (≥0.70) and calibration (Hosmer-Lemeshow test, p > 0.05). In the external validation, we observed higher predictive capability for the A and B scores, while the C score had lower but still acceptable predictive ability. CONCLUSIONS: User-friendly self-reported data accurately predict metabolic syndrome among youths from economically challenging areas.

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BACKGROUND: Ischemic stroke is an important cause of death in the world. The malignant middle cerebral artery infarction (MMCAI) has mortality as high as 80% when clinically treated. In this setting, decompressive craniectomy is a life-saving measure, in spite of high morbidity among survivors. OBJECTIVE: To evaluate the outcomes of patients with MMCAI treated with decompressive craniectomy in a Brazilian academic tertiary stroke center. METHODS: A prospective stroke database was retrospectively evaluated, and all patients treated with decompressive craniectomy for MMCAI between January 2014 and December 2017 were included. The demographics and clinical characteristics were evaluated. The functional outcome, measured by the modified Rankin Scale (mRS), was assessed at hospital discharge, after 3-months and 1-year of follow-up. RESULTS: We included 53 patients on the final analysis. The mean age was 54.6 ± 11.6 years and 64.2% were males. The median time from symptoms to admission was 4.8 (3-9.7) hours and the mean time from symptoms to surgery was 36 ± 17 hours. The left hemisphere was the affected in 39.6%. The median NIHSS at admission was 20 (16-24). The in-hospital mortality was 30.2%. After a median of 337 [157-393] days, 47.1% of patients had achieved favorable outcome (mRS ≤ 4) and 39.6% had died. CONCLUSION: Decompressive craniectomy is a life-saving measure in the setting of MMCAI, and its effects remains important in the scenario of a middle-income country in real-world situations.

ANTECEDENTES: O acidente vascular cerebral (AVC) isquêmico é uma causa importante da morte em todo o mundo. O infarto maligno da artéria cerebral média (IMACM) tem mortalidade de até 80% quando tratado clinicamente. Nesse contexto, a craniectomia descompressiva é uma medida salvadora de vidas, apesar da alta morbidade entre os sobreviventes. OBJETIVO: Avaliar os desfechos dos pacientes com IMACM tratados com craniectomia descompressiva em um centro acadêmico terciário de AVC no Brasil. MéTODOS: Um banco de dados prospectivo de AVC foi avaliado retrospectivamente e todos os pacientes tratados com craniectomia descompressiva para IMACM entre janeiro de 2014 e dezembro de 2017 foram incluídos. As características clínicas e demográficas foram avaliadas. Os desfechos funcionais, medidos pela escala modificada da Rankin (mRS), foram avaliados na alta hospitalar, após 3 meses e após 1 ano de seguimento. RESULTADOS: Foram incluídos 53 pacientes na análise final. A idade média foi 54,6 ± 11,6 anos e 64,2% eram homens. A mediana do tempo dos sintomas à admissão foi 4,8 (3­9,7) horas e o tempo médio dos sintomas à cirurgia foi 36 ± 17 horas. O hemisfério esquerdo foi o afetado em 39,6%. A pontuação na escala de AVC do National Institute of Health (NIHSS) à admissão foi 20 (16­24). A mortalidade hospitalar foi 30,2%. Após uma mediana de 337 (157­393) dias, 47,1% dos pacientes tinham atingido um desfecho favorável (mRS ≤ 4) e 39,6% tinham morrido. CONCLUSãO: Craniectomia descompressiva é uma medida salvadora de vidas no contexto do IMACM e seus efeitos permanecem importantes no cenário de um país em desenvolvimento em situação de vida real.

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Abstract Background Ischemic stroke is an important cause of death in the world. The malignant middle cerebral artery infarction (MMCAI) has mortality as high as 80% when clinically treated. In this setting, decompressive craniectomy is a life-saving measure, in spite of high morbidity among survivors. Objective To evaluate the outcomes of patients with MMCAI treated with decompressive craniectomy in a Brazilian academic tertiary stroke center. Methods A prospective stroke database was retrospectively evaluated, and all patients treated with decompressive craniectomy for MMCAI between January 2014 and December 2017 were included. The demographics and clinical characteristics were evaluated. The functional outcome, measured by the modified Rankin Scale (mRS), was assessed at hospital discharge, after 3-months and 1-year of follow-up. Results We included 53 patients on the final analysis. The mean age was 54.6 ± 11.6 years and 64.2% were males. The median time from symptoms to admission was 4.8 (3-9.7) hours and the mean time from symptoms to surgery was 36 ± 17 hours. The left hemisphere was the affected in 39.6%. The median NIHSS at admission was 20 (16-24). The in-hospital mortality was 30.2%. After a median of 337 [157-393] days, 47.1% of patients had achieved favorable outcome (mRS ≤ 4) and 39.6% had died. Conclusion Decompressive craniectomy is a life-saving measure in the setting of MMCAI, and its effects remains important in the scenario of a middle-income country in real-world situations.

Resumo Antecedentes O acidente vascular cerebral (AVC) isquêmico é uma causa importante da morte em todo o mundo. O infarto maligno da artéria cerebral média (IMACM) tem mortalidade de até 80% quando tratado clinicamente. Nesse contexto, a craniectomia descompressiva é uma medida salvadora de vidas, apesar da alta morbidade entre os sobreviventes. Objetivo Avaliar os desfechos dos pacientes com IMACM tratados com craniectomia descompressiva em um centro acadêmico terciário de AVC no Brasil. Métodos Um banco de dados prospectivo de AVC foi avaliado retrospectivamente e todos os pacientes tratados com craniectomia descompressiva para IMACM entre janeiro de 2014 e dezembro de 2017 foram incluídos. As características clínicas e demográficas foram avaliadas. Os desfechos funcionais, medidos pela escala modificada da Rankin (mRS), foram avaliados na alta hospitalar, após 3 meses e após 1 ano de seguimento. Resultados Foram incluídos 53 pacientes na análise final. A idade média foi 54,6 ± 11,6 anos e 64,2% eram homens. A mediana do tempo dos sintomas à admissão foi 4,8 (3-9,7) horas e o tempo médio dos sintomas à cirurgia foi 36 ± 17 horas. O hemisfério esquerdo foi o afetado em 39,6%. A pontuação na escala de AVC do National Institute of Health (NIHSS) à admissão foi 20 (16-24). A mortalidade hospitalar foi 30,2%. Após uma mediana de 337 (157-393) dias, 47,1% dos pacientes tinham atingido um desfecho favorável (mRS ≤ 4) e 39,6% tinham morrido. Conclusão Craniectomia descompressiva é uma medida salvadora de vidas no contexto do IMACM e seus efeitos permanecem importantes no cenário de um país em desenvolvimento em situação de vida real.

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Natural polymeric nanobiocomposites hold promise in repairing damaged bone tissue in tissue engineering. These materials create an extracellular matrix (ECM)-like microenvironment that induces stem cell differentiation. In this study, we investigated a new cytocompatible nanobiocomposite made from cotton cellulose nanofibers (CNFs) combined with chitosan polymer to induce osteogenic stem cell differentiation. First, we characterized the chemical composition, nanotopography, swelling properties, and mechanical properties of the cotton CNF/chitosan nanobiocomposite scaffold. Then, we examined the biological characteristics of the nanocomposites to evaluate their cytocompatibility and osteogenic differentiation potential using human mesenchymal stem cells derived from exfoliated deciduous teeth. The results showed that the nanobiocomposite exhibited favorable cytocompatibility and promoted osteogenic differentiation of cells without the need for chemical inducers, as demonstrated by the increase in alkaline phosphatase activity and ECM mineralization. Therefore, the cotton CNF/chitosan nanobiocomposite scaffold holds great promise for bone tissue engineering applications.

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Acute hepatic failure is characterized by rapid deterioration of hepatic function with encephalopathy in a patient without pre-existing liver disease. Bispectral index values had a significant correlation with cerebral perfusion. Transcranial Doppler can assess changes in cerebrovascular function and has the advantages of being noteworthy and widely available. This is a case report of a hepatic encephalopathy occurring during a deceased donor liver transplant in a patient presenting fulminant hepatitis. We briefly discuss some diagnostic methods highlighting the challenges of the anesthesiologist in managing this kind of patient in the context of a major surgery.

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BACKGROUND: This study evaluated the effects of systemic administration of Bifidobacterium animalis subsp. lactis HN019 (B. lactis HN019) on experimental periodontitis (EP) in rats. METHODS: Thirty-two rats were allocated to groups C (control), C-HN019 (probiotic), EP (EP only), and EP-HN019 (EP+probiotic). From day 0, the animals of C-HN019 and EP-HN019 groups received B. lactis HN019 (1 × 109 CFU/ml) daily. On the 14th day, the animals of EP and EP-HN019 groups received silk ligature around mandibular molars. Animals were euthanized on the 28th day. Samples of oral biofilm, gingival tissues, blood serum, and mandible were obtained for microtomographic, histomorphometric, microbiological, and immunological analyses. Data were statistically analyzed (p < 0.05). RESULTS: Group EP-HN019 presented significantly less alveolar bone loss when compared with Group EP in histomorphometric and microtomographic analyses. In gingival tissue and serum, Group EP-HN019 presented lower proinflammatory/anti-inflammatory cytokines ratios than Group EP. Group EP-HN019 showed higher expression of beta-defensins and less TRAP-positive cells than Group EP. Group EP presented higher gene expression of Ifng and lower gene expression of Foxp3 when compared with Group EP-HN019 in gingival tissue. In oral biofilm, EP-HN019 group presented a lower percentage of species similar to Fusobacterium periodonticum and a higher percentage of species similar to Actinomyces gereneseriae, Actinomyces israelli, and Streptococcus gordonii when compared with Group EP. There was a significant increase of B. lactis HN019 after administration of probiotic therapy in oral biofilm of Group EP-HN019. CONCLUSION: The consumption of B. lactis HN019 promotes a protective effect against alveolar bone loss by modifying local and systemic microbiological and immunoinflammatory parameters.

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In this research communication we propose a new approach by portable digital microscopy with a 200× objective to improve the visualization of microparticles of pasteurized milk submitted to the alcohol test. Not only did the method reduce the subjectivity of the readings, but also generated high resolution images of the microparticles, which allows the creation of a specific image pattern for each type of final product. In comparison to a control pasteurized milk treatment, the results confirmed the effect and the specificity of added salts (sodium citrate, disodium phosphate or their combination) on the stability of the milk to the alcohol test. Finally, the mixture of stabilizing salts of citrate/phosphate provided the highest degree of stability to pasteurized milk among the treatments studied.

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The azooxanthellate corals Tubastraea coccinea and T. tagusensis invaded the Brazilian coast in the 1980s and is still in expansion, favored by lower predation and competition pressure in their new habitats. Interestingly, the native sponge Desmapsamma anchorata has been observed overgrowing these corals. Considering that competitive displacement is expected to play a major role in the successful outcome of an invasion, the present study tested the physical and chemical mechanisms possibly involved in the competition between D. anchorata and the Tubastraea corals through field and aquaria experiments as well as the Raman spectroscopy technique for chemical analysis. Our results showed that the sponge grew in all directions including over Tubastraea colonies and regardless of its presence. There was no evidence of a specific chemical response among sponges or corals. However, we observed the extrusion of mesenteric filaments and tentacles of corals and the projection of sponge tissue during interspecific interaction, which suggests that physical imposition plays a key role for space competition at micro scales. Given the interspersed nature of benthic species distributions and the fast expansion of Tubastraea, it is unlikely that D. anchorata or any other sponges could serve a biological control against these invasive corals at larger scales, but our results showed that at a microscale they can withstand the corals presence and even outgrow them locally.

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This review is centered on the linear conjugated polyenes, which encompasses chromatic biomolecules, such as carotenoids, polyunsaturated aldehydes and polyolefinic fatty acids. The linear extension of the conjugated double bonds in these molecules is the main feature that determines the spectroscopic properties as light-absorbing. These classes of compounds are responsible for the yellow, orange, red and purple colors which are observed in their parent flora and fauna in nature. Raman spectroscopy has been used as analytical tool for the characterization of these molecules, mainly due to the strong light scattering produced by the delocalized pi electrons in the carbon chain. In addition, conjugated polyenes are one of the main target molecular species for astrobiology, and we also present a brief discussion of the use of Raman spectroscopy as one of the main analytical tools for the detection of polyenes extra-terrestrially.

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Two new 2-naphthyl squaramides, 3-methoxy -4-(2-naphtalenylamino)-3-cyclobutene-1,2-dione (SQ-NPh1) and bis-3,4-(2-naphtalenylamino)-3-cyclobutene-1,2-dione (SQ-NPh2) were synthesized via condensation reaction between the dimethylsquarate and 2-naphthylamine. The spectrometric characterization by 13C NMR confirmed the obtaining of the squaramide derivative and nor the squaraine analog. This hypothesis was corroborated by Raman and Infrared spectroscopy since the characteristic vibrational bands related to the oxocarbon portion of both structures have been assigned, such as the ones for SQ-NPh1 and SQ-NPh2. The single-crystal X-ray crystallography for SQ-NPh1 crystal structures have been solved and the structure of SQ-NPh2 have been refined using Powder Diffraction state-of-art. The SQ-NPh1 crystallizes in monoclinic system in P2/c space group. Both squaramides present absorption in the ultra-visible (220-370 nm) and fluorescent emission in the near-infrared (780-800 nm), besides they also presented high thermal stability (around 570 °C). Generally, only squaraines are reported as NIR emitters, this is the first description of NIR emission for squaramides, and since the synthesis of squaramides is very easy and the rational design of small-molecule NIR fluorophores is of high priority and great value, these results are very promising for the development of novel NIR fluorescent dyes.

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Human hair fibre is subjected to various structural modifications due to the application of chemicals such as dyes, shampoos and bleaches and/or physical procedures such as heating, and often more than one procedure is performed on the same hair. The present work aims to analyze the changes incurred in hair samples of two ethnic groups, namely Caucasian and Afro, before and after different treatments such as thermal, bleaching and straightening. In addition to observing the damage caused by each treatment separately, the study of samples that received all three treatments was carried out. For molecular structural characterization, the Raman vibrational spectroscopic technique was used and scanning electron microscopy (SEM) was used for morphological analysis of the hair fibres. This investigation has shown, through vibrational spectroscopy, that several important bonds have been modified, such as the S-S, C-S, C-C and S-O bonds as well as the secondary structures of proteins that have indergone changes in their conformation as a result of the treatment. Hair from the two ethnic groups showed small differences in relation to each applied treatment. Excessive heat generated a higher rate of Raman spectral band intensity changes when compared to the other treatments and it was observed that the action of several treatments on the same hair fibres resulted in even more pronounced structural changes. Finally, scanning electron microscopy showed that each treatment caused a different morphological deformation pattern on the capillary surface of the human hair.

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Few reports describe the effect of lactose hydrolysis on the properties of milk powder during production and storage. Hence, the aim of this study was to evaluate the effects of five different levels of enzymatic lactose hydrolysis during the production and storage of milk powder. As the lactose hydrolysis rate increased, adhesion to the drying chamber also increased, due to higher levels of particle agglomeration. Additionally, more brown powder was obtained when the lactose hydrolysis rate was increased, which in turn negatively affected rehydration ability. Using Raman spectroscopy, crystallization of the lactose residues in various samples was assessed over 6weeks of accelerated aging at a room temperature environment with 75.5% of air moisture. Products with 25% or greater lactose hydrolysis showed no signs of crystallization, in contrast to the non-hydrolyzed sample.

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This work used L-tartaric acid as a model molecule to evaluate how the use of inert and oxidizing atmospheres during pyrolysis affected the physical and optical properties of the resulting carbon dots (CDs). Pyrolysis revealed to be a simple procedure that afforded CDs in a single step, dismissed the addition of organic solvents, and involved only one extraction stage that employed water. By X-ray diffraction a dependency between the structure of the CDs and the atmosphere (oxidizing or inert) used during the pyrolysis was found. Potentiometric titration demonstrated that the CDs were largely soluble in water; it also aided characterization of the various groups that contained sp(3) -hybridized carbon atoms on the surface of the dots. Raman spectroscopy suggested that different amounts of sp(2)- and sp(3)-hybridized carbon atoms emerged on the CDs depending on the pyrolysis atmosphere. In conclusion, the pyrolysis atmosphere influenced the physical properties, such as the composition and the final structure.

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FT-Raman spectroscopy has been explored as a quick screening method to evaluate the presence of lactose and identify milk powder samples adulterated with maltodextrin (2.5-50% w/w). Raman measurements can easily differentiate samples of milk powder, without the need for sample preparation, while traditional quality control methods, including high performance liquid chromatography, are cumbersome and slow. FT-Raman spectra were obtained from samples of whole lactose and low-lactose milk powder, both without and with addition of maltodextrin. Differences were observed between the spectra involved in identifying samples with low lactose content, as well as adulterated samples. Exploratory data analysis using Raman spectroscopy and multivariate analysis was also developed to classify samples with PCA and PLS-DA. The PLS-DA models obtained allowed to correctly classify all samples. These results demonstrate the utility of FT-Raman spectroscopy in combination with chemometrics to infer about the quality of milk powder.

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In this work, FT-Raman spectroscopy was explored to evaluate spreadable cheese samples. A partial least squares discriminant analysis was employed to identify the spreadable cheese samples containing starch. To build the models, two types of samples were used: commercial samples and samples manufactured in local industries. The method of supervised classification PLS-DA was employed to classify the samples as adulterated or without starch. Multivariate regression was performed using the partial least squares method to quantify the starch in the spreadable cheese. The limit of detection obtained for the model was 0.34% (w/w) and the limit of quantification was 1.14% (w/w). The reliability of the models was evaluated by determining the confidence interval, which was calculated using the bootstrap re-sampling technique. The results show that the classification models can be used to complement classical analysis and as screening methods.

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There are few studies about different types of chocolate and their chemical characterization by Fourier transform (FT)-Raman spectroscopy and capillary zone electrophoresis (CZE). The aim of this study was to evaluate the lipid profile of different types of Brazilian chocolate through characterization by FT-Raman spectroscopy and identification and quantification of major fatty acids (FAs) by CZE to confirm FT-Raman spectrometry results. It was found that the main spectroscopic profile difference of the chocolate samples analyzed was related to the presence of saturated or unsaturated FAs. Well defined bands at approximately 1660, 1267, and 1274 cm(-1) corresponding to vibrational modes of unsaturated FAs (UnFAs) were found only in the spectra of samples with cocoa butter in their composition according to label specifications, mainly in dark chocolate samples. The FA identification and quantification by CZE found the presence of stearic (18:0) and palmitic (16:0) acids as the major saturated FAs in all chocolate samples. Dark chocolate samples showed the highest levels of oleic (cis-9 18:1) and linoleic (cis, cis -9,12 18:2) UnFAs monitored and the lowest levels of 14:0 in their chemical composition. Samples coded as 02 (with not only cocoa butter in their composition according to label) had the highest levels of 14:0 (FA not present in cocoa butter composition) corresponding to label information and inferring the presence of other fat sources, called cocoa butter substitutes, mainly for milk and white chocolate samples. This study suggests FT-Raman spectroscopy is a powerful technique that can be used to chemically characterize the chocolate lipid fraction, and CZE is a tool able to confirm Raman spectroscopy results and identify and quantify the major FAs in chocolate samples.

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The aim of the present study was to characterize 16 pharmaceutical grade chondroitin sulfate (CS) samples, concerning the structure and presence of contaminants, in comparison to USP and analytical grade CS. Agarose gel electrophoresis has shown that only 5 samples were >90% CS, while 11 contained less than 15% CS. FACE (fluorophore-assisted carbohydrate electrophoresis) revealed that maltodextrin was the main contaminant in nine of them, and lactose in two. Raman spectroscopy corroborated these results. Concerning the structure of the CS present in the five CS-rich samples, the ratios 4-sulfated:6-sulfated disaccharides varied from 0.9 to 1.7, and their modal molecular weight was 20-29 kDa. Also, they were all contaminated by small amounts of keratan sulfate (<1%). In conclusion, our findings indicate that the composition of CS preparations not always corresponds to the manufacturers' descriptions, and indicate that further characterization should be required for the registry and license of pharmaceutical grade CS.

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Protein systems (PS) are routinely used by companies from Brazil and around the globe to improve the texture, yield, and palatability of processed foods. Understanding the synergistic behavior among the different protein structures of these systems during thermal treatment under the influence of pH can help to better define optimum conditions for products and processes. The interpretation of the reactions and interactions that occur simultaneously among the protein constituents of these systems as dispersions during thermal processing is still a major challenge. Here, using a rapid viscosity analyzer, we observed the rheological changes in the startup viscosities of 5 PS obtained by combining varying proportions of milk protein concentrate and whey protein concentrate under different conditions of pH (5.0, 6.5, and 7.0) and heat processing (85°C/15min and 95°C/5min). The solutions were standardized to 25% of total solids and 17% of protein. Ten analytical parameters were used to characterize each of the startup-viscosity ramps for 35 experiments conducted in a 2×3 × 5 mixed planning matrix, using principal component analysis to interpret behavioral similarities. The study showed the clear influence of pH 5.5 in the elevation of the initial temperature of the PS startup viscosity by at least 5°C, as well as the effect of different milk protein concentrate:whey protein concentrate ratios above 15:85 at pH 7.0 on the viscographic profile curves. These results suggested that the primary agent driving the changes was the synergism among the reactions and interactions of casein with whey proteins during processing. This study reinforces the importance of the rapid viscosity analyzer as an analytical tool for the simulation of industrial processes involving PS, and the use of the startup viscosity ramp as a means of interpreting the interactions of system components with respect to changes related to the treatment temperature.

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This work presents the Raman spectroscopic characterization of synthetic analogs of natural conjugated polyenals found in octocorals, focusing the unequivocal identification of the chemical species present in these systems. The synthetic material was produced by the autocondensation reaction of crotonaldehyde, generating a demethylated conjugated polyene containing 11 carbon-carbon double bonds, with just a methyl group on the end of the carbon chain. The resonance Raman spectra of such pigment has shown the existence of enhanced modes assigned to ν1(CC) and ν2(CC) modes of the main chain. For the resonance Raman spectra of natural pigments from octocorals collected in the Brazilian coast, besides the previously cited bands, it could be also observed the presence of the ν4(CCH3), related to the vibrational mode who describes the vibration of the methyl group of the central carbon chain of carotenoids. Other interesting point is the observation of overtones and combination bands, which for carotenoids involves the presence of the ν4 mode, whereas for the synthetic polyene this band, besides be seen at a slightly different wavenumber position, does not appear as an enhanced mode and also as a combination, such as for the natural carotenoids. Theoretical molecular orbital analysis of polyenal-11 and lycopene has shown the structural differences which are also responsible for the resonance Raman data, based on the appearance of the (CH3) vibrational mode in the resonant transition only for lycopene. At last, the Raman band at ca. 1010 cm(-1), assigned to the (CH3) vibrational mode, can be used for attributing the presence of each one of the conjugated polyenes: the resonance Raman spectrum containing the band at ca. 1010 cm(-1) refers to the carotenoid (in this case lycopene), and the absence of such band in resonance conditions refers to the polyenal (in this case the polyenal-11).

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Frankfurters are widely consumed all over the world, and the production requires a wide range of meat and non-meat ingredients. Due to these characteristics, frankfurters are products that can be easily adulterated with lower value meats, and the presence of undeclared species. Adulterations are often still difficult to detect, due the fact that the adulterant components are usually very similar to the authentic product. In this work, FT-Raman spectroscopy was employed as a rapid technique for assessing the quality of frankfurters. Based on information provided by the Raman spectra, a multivariate classification model was developed to identify the frankfurter type. The aim was to study three types of frankfurters (chicken, turkey and mixed meat) according to their Raman spectra, based on the fatty vibrational bands. Classification model was built using partial least square discriminant analysis (PLS-DA) and the performance model was evaluated in terms of sensitivity, specificity, accuracy, efficiency and Matthews's correlation coefficient. The PLS-DA models give sensitivity and specificity values on the test set in the ranges of 88%-100%, showing good performance of the classification models. The work shows the Raman spectroscopy with chemometric tools can be used as an analytical tool in quality control of frankfurters.

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