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1.
Mikrochim Acta ; 191(10): 603, 2024 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-39284926

RESUMO

A simple method has been developed for semi-quantitative analysis of the colorimetric output of loop-mediated isothermal amplification (LAMP) using a 3D-printed tube holder with a smartphone and notebook for the detection of Raillietina, which is the cause of Raillietiniasis affecting free-range chicken farming. In this method, a light is directed from a notebook screen to the LAMP products in the tube holder and the color absorption of the LAMP products is measured by using the appropriate smartphone application. It was found that the malachite green dye-coupled LAMP (MaG-LAMP) assay showed the highest sensitivity and specificity for detecting Raillietina without any cross-reaction with other related parasites and hosts. The limit of detection was 10 fg/µL of DNA. A total of 60 fecal samples were infectively confirmed by microscopic examination and the results of microscopy compared with those of MaG-LAMP and triplex PCR assays. Microscopy and MaG-LAMP based on the color absorption demonstrated high agreement in Raillietina detection with kappa = 1. Rapid, simple, cost-effective, and easy interpretation of colorimetric LAMP assays and their high sensitivity make them superior to PCR and morphological investigation, demonstrating the feasibility of this assay in point-of-care screening to support farm management and solve chicken health problems. Our study presents is an alternative diagnostic method using semi-quantitative analysis of colorimetric LAMP based on the differing solution color absorptions between positive and negative reactions for infectious disease diagnosis.


Assuntos
Galinhas , Colorimetria , Técnicas de Amplificação de Ácido Nucleico , Impressão Tridimensional , Smartphone , Colorimetria/métodos , Colorimetria/instrumentação , Técnicas de Amplificação de Ácido Nucleico/métodos , Animais , Limite de Detecção , Corantes de Rosanilina/química , Técnicas de Diagnóstico Molecular/instrumentação , Técnicas de Diagnóstico Molecular/métodos , Fezes/química , Fezes/microbiologia
2.
J Prosthodont ; 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38872321

RESUMO

PURPOSE: Many factors can affect the aesthetics of dental restorations, including the instrumental techniques used in shade matching, and can lead to clinical failure. The aim of this study was to investigate the effectiveness of using the cross-polarization digital photograph technique and intraoral scanners for shade matching, and also evaluate the effect of the level of clinical experience on shade matching success. MATERIALS AND METHODS: Color analysis was performed on the maxillary right central incisors of 10 subject models with Vita Easyshade. Intraoral scanning was performed 10 times on each model using TRIOS 3 and color analysis was performed from the same spot. Then cross-polarized and non-polarized photographs of the models were taken with standard settings using a gray reference card. Each shade tab of the Vita System 3D-Master scale was also photographed with two different polarization techniques. Four groups (n = 12), including prosthodontics faculty staff, postgraduate students in prosthodontics, undergraduate students, and dental technicians matched the shade tabs and the model photographs obtained with both techniques on a standardized computer screen. Finally, the color differences between the shade tabs and maxillary central incisors matched by observers from four different groups were recorded using a colorimeter, Classic Color Meter, in accordance with the CIELAB system and CIEDE2000 (ΔE00) values were calculated. The data were compared with the acceptability threshold of 1.80 for ΔE00. The data obtained from the observers were analyzed with IBM SPSS Statistics 26.0 Release Notes program. Independent Samples t-test was used to compare normally distributed data according to binary groups. The level of significance was 0.05. RESULTS: A statistically significant difference was found in the shade matching on photographs taken with different techniques in postgraduate students (p = 0.02). Also, there was a statistically significant difference in success between the groups that made shade matching based on photographs obtained with the non-polarization technique (p = 0.00). The undergraduate students achieved statistically significantly lower results than all other groups (ΔE00 = 5.57 ± 1.07). The kappa value between the intraoral scanner and spectrophotometer results was 0.10, and this value was not statistically significant (p = 0.32). CONCLUSIONS: The cross-polarization technique used especially for shade matching is not superior to the non-polarization technique. Academic and clinical experience might be correlated with shade-matching success with the non-polarization technique. The clinical acceptability threshold could not be achieved in the shade matchings made on digital photographs taken with both techniques. Shade matching performed with an intraoral scanner did not yield reliable results.

3.
Sensors (Basel) ; 23(6)2023 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-36992044

RESUMO

Classifying pixels according to color, and segmenting the respective areas, are necessary steps in any computer vision task that involves color images. The gap between human color perception, linguistic color terminology, and digital representation are the main challenges for developing methods that properly classify pixels based on color. To address these challenges, we propose a novel method combining geometric analysis, color theory, fuzzy color theory, and multi-label systems for the automatic classification of pixels into 12 conventional color categories, and the subsequent accurate description of each of the detected colors. This method presents a robust, unsupervised, and unbiased strategy for color naming, based on statistics and color theory. The proposed model, "ABANICCO" (AB ANgular Illustrative Classification of COlor), was evaluated through different experiments: its color detection, classification, and naming performance were assessed against the standardized ISCC-NBS color system; its usefulness for image segmentation was tested against state-of-the-art methods. This empirical evaluation provided evidence of ABANICCO's accuracy in color analysis, showing how our proposed model offers a standardized, reliable, and understandable alternative for color naming that is recognizable by both humans and machines. Hence, ABANICCO can serve as a foundation for successfully addressing a myriad of challenges in various areas of computer vision, such as region characterization, histopathology analysis, fire detection, product quality prediction, object description, and hyperspectral imaging.

4.
Behav Res Methods ; 55(8): 4086-4098, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-36357762

RESUMO

Synesthesia is a phenomenon where sensory stimuli or cognitive concepts elicit additional perceptual experiences. For instance, in a commonly studied type of synesthesia, stimuli such as words written in black font elicit experiences of other colors, e.g., red. In order to objectively verify synesthesia, participants are asked to choose colors for repeatedly presented stimuli and the consistency of their choices is evaluated (consistency test). Previously, there has been no publicly available and easy-to-use tool for analyzing consistency test results. Here, the R package synr is introduced, which provides an efficient interface for exploring consistency test data and applying common procedures for analyzing them. Importantly, synr also implements a novel method enabling identification of participants whose scores cannot be interpreted, e.g., who only give black or red color responses. To this end, density-based spatial clustering of applications with noise (DBSCAN) is applied in conjunction with a measure of spread in 3D space. An application of synr with pre-existing openly accessible data illustrating how synr is used in practice is presented. Also included is a comparison of synr's data validation procedure and human ratings, which found that synr had high correspondence with human ratings and outperformed human raters in situations where human raters were easily mislead. Challenges for widespread adoption of synr as well as suggestions for using synr within the field of synesthesia and other areas of psychological research are discussed.


Assuntos
Transtornos da Percepção , Humanos , Sinestesia , Percepção de Cores/fisiologia
5.
Clin Oral Investig ; 26(3): 2527-2536, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34654942

RESUMO

OBJECTIVES: Although bleaching therapy is considered a dose-dependent treatment, the effect of the volume of product used is yet to be studied. This study thus aimed to evaluate the influence of bleaching gel volume on chromatic alteration and postoperative sensitivity. METHODOLOGY: Thirty patients were selected and allocated into three groups; the lower canines were analyzed according to the volume of gel used: GI-0.025 mL, GII-0.05 mL, and GIII-0.10 mL. Chromatic alteration analysis was performed using a portable digital spectrophotometer by calculating the ΔE, ΔE00, ΔL*, Δa*, and Δb* values and the whiteness index (WID). Spontaneous sensitivity was assessed using a questionnaire, and sensitivity was stimulated by thermo-sensory analysis. Analyses were conducted in five stages: baseline, after 1st, 2nd, and 3rd bleaching sessions, and 14 days after the end. Data were analyzed using the two-way ANOVA test with repeated measures and Tukey's post hoc test (p < 0.05). RESULTS: It was observed that ΔE, ΔE00, and ΔL* were similar between groups at the end of the bleaching therapy; and the values of Δa*, Δb*, and WID were higher in the GIII group. For sensitivity, it was found that the GI was the one with the lowest values; o GII intermediate values; while the GIII group presents the highest values of spontaneous and stimulated sensitivity. CONCLUSION: Gel volume influenced the response to bleaching and significantly influenced the spontaneous sensitivity and cold stimulus. CLINICAL RELEVANCE: The amount of bleaching gel used during therapy is key to both the response to color change and postoperative sensitivity.


Assuntos
Clareadores Dentários , Clareamento Dental , Cor , Humanos , Peróxido de Hidrogênio , Ácido Hipocloroso , Espectrofotometria , Clareadores Dentários/uso terapêutico
6.
Molecules ; 27(7)2022 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-35408458

RESUMO

Basil-based semi-finished products, which are mainly used as an intermediate to produce the typical pesto sauce, are prepared and exported all over the world. Color is a fundamental organoleptic requirement for the acceptability of these semi-finished products by the manufacturers of the pesto sauce. Some alternative formulations, which adjust the typical industrial recipe by both changing the preservative agent (ascorbic acid, citric acid, or a mixture of both) and introducing a preliminary thermic treatment (blast chilling), were evaluated. In this work, a fast and non-destructive spectrophotometric analysis, to monitor the color variations in these food products during their shelf-life, was proposed. The raw diffuse reflectance spectra (380-900 nm) obtained by a UV-visible spectrophotometer, endowed with an integrating sphere, together with the CIELab parameters (L*, a*, b*) automatically obtained from these, were considered, and elaborated using multivariate statistical analysis (principal component analysis). From this preliminary study, blast chilling, together with the use of ascorbic acid, proved to be the best solution to better preserve the color of these products during their shelf-life.


Assuntos
Ocimum basilicum , Antioxidantes , Ácido Ascórbico , Cor
7.
Molecules ; 26(4)2021 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-33669220

RESUMO

This study aimed to compare folate contents in hen eggs from four different farming systems, namely organic, free range, barn, and cage one. Folate retention during egg boiling was studied as well. The contents of individual folate vitamers were determined using the high-performance liquid chromatography method (HPLC), following trienzyme treatment. Folate content in eggs differed significantly (p < 0.05) due to the rearing system, with the highest mean content determined in the eggs from organic farming (113.8 µg/100 g). According to this study, one egg (60 g) may provide 40-86 µg of folates, which corresponds to 10-22% of the recommended daily intake for adults, 400 µg according to the Nutrition Standards for the Polish Population. The predominant folate form found in egg was 5-methyltetrahydrofolate, which showed considerably greater stability under boiling compared to 10-formylfolic acid present in a lower amount. In most eggs tested, the losses in total folate content did not exceed 15%. The color of yolk of the most folate-abundant organic eggs, had the highest value of lightness (L*) and the lowest value of redness (a*). This, however, does not correspond to consumer preferences of intense golden yolk color.


Assuntos
Agricultura , Gema de Ovo/química , Ovos/análise , Ácido Fólico/análise , Adolescente , Adulto , Animais , Galinhas , Criança , Pré-Escolar , Cor , Culinária , Feminino , Ácido Fólico/química , Humanos , Lactente , Masculino , Ácido Poliglutâmico/análogos & derivados , Ácido Poliglutâmico/química , Tetra-Hidrofolatos/química , Adulto Jovem
8.
J Sci Food Agric ; 101(10): 4201-4206, 2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-33420739

RESUMO

BACKGROUND: The poor palatability, low digestibility, and unpleasant color of parboiled rice (PR) have severely hampered its acceptance by consumers. It is hence necessary and urgent to develop a new method for producing high-quality PR. In the current study, the effect of high hydrostatic pressure (HHP) pre-soaking on the color, textural properties, and the degree of retrogradation of PR was investigated. RESULTS: With HHP from 100 to 500 MPa, the water adsorption rate increased and cooking time decreased. Parboiled rice samples presented higher lightness scores (L) and had lower color intensity (B). Compared with a control group, PR samples treated with high-pressure pre-soaking showed a reduction of hardness values from 0.69% to 32.99%, and gumminess values also decreased from 8.58% to 33.62%. The differential scanning calorimetry (DSC) results indicated that the enthalpy values of PR samples decreased after high pressure pre-soaking. The molecular structure of PR characterized by Fourier transform infrared spectrometry confirmed that HHP pre-soaking could decrease the retrogradation level. CONCLUSION: The findings outlined above suggest that the texture and retrogradation properties of PR were improved after high-pressure pre-soaking. © 2021 Society of Chemical Industry.


Assuntos
Culinária/métodos , Manipulação de Alimentos/métodos , Oryza/química , Varredura Diferencial de Calorimetria , Culinária/instrumentação , Dureza , Temperatura Alta , Pressão Hidrostática , Sementes/química
9.
Skin Res Technol ; 26(5): 639-647, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32180266

RESUMO

BACKGROUND: Excessive wiping friction in skin care may lead to skin damage. Bed baths are required to remove skin dirt without affecting the skin barrier function; the wiping pressure and number of wipings that satisfy these two requirements have not been clarified. This study aimed to determine the minimum wiping pressure and number of wipings that can remove skin dirt. MATERIALS AND METHODS: In this quasi-experimental study, 50 healthy adults received an adhesion of pseudo-oily and aqueous dirt, randomly assigned to the left and right forearms. Each participant was wiped three times with wiping pressure classified into six randomly assigned categories. The dirt removal rate was calculated by color-analyzing images captured before and after each wiping, and its dependence on the combination of wiping pressure and number of wipings was assessed using a linear mixed model. RESULTS: The combinations achieving oily dirt removal rates of 80% or more were wiping once and pressure ≥50 mmHg, wiping twice and pressure ≥40 mmHg, and wiping thrice and pressure ≥10 mmHg. Aqueous dirt was removed almost completely by wiping once, even with pressure ≥5 mmHg. CONCLUSION: Wiping with at least 10 mmHg or more three times can sufficiently remove both oily and aqueous dirt. Dirt removal rates with weak pressure can be made about as effective as those achieved with strong pressure by increasing the number of wipings. This result can be applied to daily nursing, home care, and long-term care health facilities.


Assuntos
Interpretação de Imagem Assistida por Computador , Higiene da Pele , Pele , Adulto , Fricção , Humanos , Higiene da Pele/métodos , Água
10.
Sensors (Basel) ; 19(9)2019 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-31052169

RESUMO

An algorithm was proposed for automatic tomato detection in regular color images to reduce the influence of illumination and occlusion. In this method, the Histograms of Oriented Gradients (HOG) descriptor was used to train a Support Vector Machine (SVM) classifier. A coarse-to-fine scanning method was developed to detect tomatoes, followed by a proposed False Color Removal (FCR) method to remove the false-positive detections. Non-Maximum Suppression (NMS) was used to merge the overlapped results. Compared with other methods, the proposed algorithm showed substantial improvement in tomato detection. The results of tomato detection in the test images showed that the recall, precision, and F1 score of the proposed method were 90.00%, 94.41 and 92.15%, respectively.


Assuntos
Técnicas Biossensoriais , Cor , Aprendizado de Máquina , Solanum lycopersicum/crescimento & desenvolvimento , Algoritmos , Humanos , Solanum lycopersicum/química , Máquina de Vetores de Suporte
11.
Sensors (Basel) ; 19(21)2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31671690

RESUMO

Saliva has gained considerable attention as a diagnostics alternative to blood analyses. A wide spectrum of salivary compounds is correlated to blood concentrations of biomarkers, providing informative and discriminative data regarding the state of health. Intra-oral detection and assessment of food and beverage intake can be correlated and provides valuable information to forecast the formation and modification of salivary biomarkers. In this context, the present work proposes a novel intra-oral optical fiber sensor, developed around an optical coupler topology, and exemplified on the detection and assessment of wine intake, which is accounted for example for the formation of Nε-carboxymethyllysine Advanced Glycation End-products. A laboratory proof of concept validates the proposed solution on four white and four red wine samples. The novel optical sensor geometry shows good spectral properties, accounting for selectivity with respect to grape-based soft drinks. This enables intra-oral detection and objective quality assessment of wine. Moreover, its implementation exploits the advantages of fiber-optics sensing and facilitates integration into a mouthguard, holding considerable potential for real-time biomedical applications to investigate Advanced Glycation End-products in the saliva and their connection with consumption of wine, for the evaluation of risk factors in diet-related diseases.


Assuntos
Sistemas Computacionais , Óptica e Fotônica/instrumentação , Vinho/análise , Cor , Fibras Ópticas , Análise Espectral , Vitis
12.
J Prosthodont ; 28(1): e96-e102, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29533497

RESUMO

PURPOSE: To determine the effects of age and gender on the color distribution of the right maxillary central, lateral incisors, and canine teeth. MATERIALS AND METHODS: The tooth color was measured using the VITA Easyshade V spectrophotometer with a total of 202 volunteers (89 men, 113 women). The age distribution in this study was between 15 and 70 years old (average: 31). A grey background color was used to prevent background reflection while performing the color measurements. RESULTS: According to the VITAPAN Classical shade guide, the tooth color distribution of the central and lateral incisors showed a maximum of A2, with a maximum of B3 for the canine teeth. When comparing the International Commission on Illumination L* , a* , and b* values (CIELab color space coordinates) of the teeth with subject gender, statistically significant differences were not found between gender and the L* and b* values (p > 0.05); however, a statistically significant difference was observed between gender and the a* values (p < 0.05). CONCLUSION: When the distribution ratio of tooth color was examined, different ratios were determined based on gender and age and between the maxillary central, lateral incisors, and canine teeth. A uniform tooth color should not be chosen for anterior restorations, and factors such as gender and age should be considered when making a color selection for patients.


Assuntos
Dente/anatomia & histologia , Adolescente , Adulto , Fatores Etários , Idoso , Cor , Dente Canino/anatomia & histologia , Feminino , Humanos , Incisivo/anatomia & histologia , Masculino , Maxila , Pessoa de Meia-Idade , Fatores Sexuais , Espectrofotometria , Descoloração de Dente/diagnóstico , Adulto Jovem
13.
Molecules ; 23(2)2018 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-29461498

RESUMO

This study was performed to evaluate the metabolite recovery from different extraction methods applied to Thymusalgeriensis aerial parts. A high-performance liquid chromatographic method using photodiode array detector with gradient elution has been developed and validated for the simultaneous estimation of different phenolic compounds in the extracts and in their corresponding purified fractions. The experimental results show that microwave-assisted aqueous extraction for 15 min at 100 °C gave the most phenolics-enriched extract, reducing extraction time without degradation effects on bioactives. Sixteen compounds were identified in this extract, 11 phenolic compounds and five flavonoids, all known for their biological activities. Color analysis and determination of chlorophylls and carotenoids implemented the knowledge of the chemical profile of this plant.


Assuntos
Carotenoides/química , Fenóis/química , Compostos Fitoquímicos/química , Thymus (Planta)/química , Carotenoides/isolamento & purificação , Flavonoides/química , Flavonoides/isolamento & purificação , Fenóis/isolamento & purificação , Compostos Fitoquímicos/isolamento & purificação , Componentes Aéreos da Planta/química , Extratos Vegetais/química
14.
Molecules ; 23(8)2018 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-30082629

RESUMO

A method using high-performance liquid chromatography coupled with a photodiode array detector was proposed for the rapid characterization of different phenolic constituents from the extracts of Atriplex mollis aerial parts. Atriplex species are known for their multiple biological activities, but no information is available in the literature about A. mollis. With the aim to firstly characterize the main secondary metabolites of this plant, so as to orient better the biological evaluation, we applied three different extraction procedures and compared the chromatographic results. Microwave-assisted extraction gave the best yield and recovery of important compounds such as gallic acid, catechin, chlorogenic acid, p-OH benzoic acid, rutin, sinapinic acid, t-ferulic acid, naringenin and benzoic acid. These constituents belong to three important chemical classes: phenolic acids, flavonoids and monoterpenes. Color evaluation and analysis of chlorophylls (a and b) and carotenoids complete the preliminary profile of this plant. From these analyses, Atriplex mollis is a source of bioactive compounds (especially rutin, t-ferulic acid and gallic acid) and could be recommended as a plant of phyto-pharmaceutical relevance, opening new perspectives on this salt-tolerant plant.


Assuntos
Atriplex/química , Componentes Aéreos da Planta/química , Carotenoides/química , Cromatografia Líquida de Alta Pressão/métodos , Flavonoides/química , Hidroxibenzoatos/química , Monoterpenos/química
15.
Skin Res Technol ; 23(2): 186-193, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27514310

RESUMO

BACKGROUND: Rosacea is a common chronic inflammatory disorder affecting facial skin. Currently, no accurate and objective method is available for assessing the severity of rosacea. Most studies use the National Rosacea Society Standard (NRSS) grading method, which lacks objectivity and yields varying results. METHODS: Eighteen patients with rosacea were included. Clinical severity was assessed on the basis of the NRSS grade, Investigators' Global Assessment, Patients' Global Assessment, and Dermatology Quality of Life Index. A skin color analysis system was used to measure the facial area showing erythema, and biophysical parameters of facial skin (transepidermal water loss and skin surface hydration) were examined. To find statistical significant in classification severity of the rosacea, statistical analysis was performed with all parameters. RESULTS: A significant correlation (P < 0.05) was found between the NRSS grade, facial area showing erythema, and biophysical parameters. The latter two factors differed significantly among patients with rosacea of different levels of severity (mild, moderate, severe; P < 0.05). CONCLUSION: Color imaging systems can be useful and reliable for evaluating the severity of rosacea, in addition to biophysical parameter assessment. The combination of these two analytical methods enabled objective and quantitative evaluation of the severity of rosacea.


Assuntos
Colorimetria/métodos , Dermoscopia/métodos , Rosácea/diagnóstico , Rosácea/fisiopatologia , Índice de Gravidade de Doença , Pigmentação da Pele , Perda Insensível de Água , Diagnóstico por Computador/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
16.
Skin Res Technol ; 21(4): 466-73, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25809473

RESUMO

BACKGROUND/PURPOSE: Early detection of malignant melanoma is an important public health challenge. In the USA, dermatologists are seeing more melanomas at an early stage, before classic melanoma features have become apparent. Pink color is a feature of these early melanomas. If rapid and accurate automatic detection of pink color in these melanomas could be accomplished, there could be significant public health benefits. METHODS: Detection of three shades of pink (light pink, dark pink, and orange pink) was accomplished using color analysis techniques in five color planes (red, green, blue, hue, and saturation). Color shade analysis was performed using a logistic regression model trained with an image set of 60 dermoscopic images of melanoma that contained pink areas. Detected pink shade areas were further analyzed with regard to the location within the lesion, average color parameters over the detected areas, and histogram texture features. RESULTS: Logistic regression analysis of a separate set of 128 melanomas and 128 benign images resulted in up to 87.9% accuracy in discriminating melanoma from benign lesions measured using area under the receiver operating characteristic curve. The accuracy in this model decreased when parameters for individual shades, texture, or shade location within the lesion were omitted. CONCLUSION: Texture, color, and lesion location analysis applied to multiple shades of pink can assist in melanoma detection. When any of these three details: color location, shade analysis, or texture analysis were omitted from the model, accuracy in separating melanoma from benign lesions was lowered. Separation of colors into shades and further details that enhance the characterization of these color shades are needed for optimal discrimination of melanoma from benign lesions.


Assuntos
Colorimetria/métodos , Dermoscopia/métodos , Melanoma/patologia , Reconhecimento Automatizado de Padrão/métodos , Neoplasias Cutâneas/patologia , Aprendizado de Máquina Supervisionado , Algoritmos , Cor , Sistemas Computacionais , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Pigmentação da Pele
17.
Breed Sci ; 64(4): 416-21, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25914598

RESUMO

Chlorosis level is a useful parameter to assess imidazolinone resistance in sunflower (Helianthus annuus L.). The aim of this study was to quantify chlorosis through two different methods in sunflower plantlets treated with imazapyr. The genotypes used in this study were two inbred lines reported to be different in their resistance to imidazolinones. Chlorosis was evaluated by spectrophotometrical quantification of photosynthetic leaf pigments and by a bioinformatics-based color analysis. A protocol for pigment extraction was presented which improved pigment stability. Chlorophyll amount decreased significantly when both genotypes were treated with 10 µM of imazapyr. Leaf color was characterized using Tomato Analyzer(®) color test software. A significant positive correlation between color reduction and chlorophyll concentration was found. It suggests that leaf color measurement could be an accurate method to estimate chlorosis and infer chlorophyll levels in sunflower plants. These results highlight a strong relationship between imidazolinone-induced chlorosis and variations in leaf color and in chlorophyll concentration. Both methods are quantitative, rapid, simple, and reproducible. Thus, they could be useful tools for phenotyping and screening large number of plants when breeding for imidazolinone resistance in this species.

18.
Biosensors (Basel) ; 14(8)2024 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-39194606

RESUMO

Food safety control is a key issue in the food and agriculture industries. For such purposes, developing miniaturized analytical methods is critical for enabling the rapid and sensitive detection of food supplements, allergens, and pollutants. Here, a novel bioanalytical methodology based on DNA-functionalized gold nanoparticles (AuNPs) and colorimetric detection was developed to detect the presence of sesame (a major allergen) through sesame seed DNA as a target, in food samples. The presence of sesame DNA induces controlled nanoparticle aggregation/desegregation, resulting in a color change (from blue to red) proportional to sesame DNA concentration. The incorporation of multicomponent nucleic acid enzymes (MNAzymes) in this strategy has been carried out to perform an isothermal signal amplification strategy to improve the sensitivity of detection. Also, open-source software for color analysis was used to ensure an unbiased visual color-change detection, enhancing detection accuracy and sensitivity and opening the possibility of performing a simple and decentralized analyte detection. The method successfully detected the presence of sesame DNA in sesame seed, sesame oil, olive oil, and sunflower oil. In brief, the developed approach constitutes a simple and affordable alternative to perform a highly sensitive detection of DNA in food without complex methodologies or the requirement of expensive instrumentation.


Assuntos
Colorimetria , Ouro , Nanopartículas Metálicas , Sesamum , Ouro/química , Nanopartículas Metálicas/química , Análise de Alimentos/métodos , Técnicas Biossensoriais , DNA , DNA de Plantas/análise
19.
Materials (Basel) ; 17(10)2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38793280

RESUMO

Electrochromism has emerged as a pivotal technology in the pursuit of energy efficiency and environmental sustainability, spurring significant research efforts aimed at the creation of advanced electrochromic devices. Most electrochromic materials are used for smart window applications. However, current electrochromic materials have been applied to new energy vehicles, cell phone back covers, AR glasses, and so on. More application scenarios put forward more requirements for the color of the colored states. Choosing the right color change in the application will be the trend in the future. In this work, tungsten trioxide (WO3) thin films were prepared by adjusting the in situ heating temperature. WO3 with a crystalline structure showed excellent cyclic stability (5000 cycles), electrochromic performance (ΔT = 77.7% at 633 nm, CE = 37.1 cm2/C), relatively fast bleaching/coloring speed (20.0 s/19.4 s), and the darkest coloring effect (L* = 29.32, a* = 7.41, b* = -22.12 for the colored state). These findings offer valuable insights into the manipulation of smart materials and devices, contributing to the advancement of electrochromic technology.

20.
Food Res Int ; 190: 114638, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38945627

RESUMO

Tea trichomes were regarded as an essential evaluation index for reflecting tea flavor quality in terms of aroma and influence on infusion color. This study reveals the impact of golden oxidized trichomes on the color, volatile and non-volatile metabolites of black teas through comparative metabolomics combined quantitative analysis on hongbiluo (trichomes-deficiency black teas), hongjinluo (trichomes-rich black teas), and trichomes (from hongjinluo). Forty-six volatile components were detected using headspace solid-phase microextraction gas chromatography-mass spectrometry, while the results suggested that the contribution of trichomes to black teas is limited. A total of 60 marker non-volatile compounds were identified, including catechins, catechin oxidation products, flavonoid glycosides, organic acids, hydrolysable tannins and amino acids. Notably, p-coumaroyl-kaempferol glucosides, and catechin dimers demonstrated high levels in independent trichomes and showed a positive correlation with the brightness and yellow hue of black tea infusions, specifically kaempferol 3-O-di-(p-coumaroyl)-hexoside. Furthermore, results from fractional extraction analysis of separated trichomes provided that N-ethyl-2-pyrrolidinone-substituted epicatechin gallates, acylated kaempferol glycosides, and chromogenic catechins dimers, such as theaflavins, were primary color contributors in oxidized trichomes. Especially, we found that epicatechin gallate (ECG) and its derivates, 3'-O-methyl-ECG and N-ethyl-2-pyrrolidinone-substituted ECG, highly accumulated in trichomes, which may be associated with the varieties of hongbiluo and hongjinluo black teas. Eventually, addition tests were applied to verify the color contribution of trichome mixtures. Our findings employed comprehensive information revealing that golden oxidized trichomes contributed significantly to the brightness and yellow hue of black tea infusion, but their contribution to the aroma and metabolic profile is limited. These findings may contribute to the effective modulation of the infusion color during black tea production by regulating the proportion of tea trichomes or screening trichomes-rich or deficiency varieties.


Assuntos
Camellia sinensis , Cor , Cromatografia Gasosa-Espectrometria de Massas , Metabolômica , Oxirredução , Chá , Tricomas , Compostos Orgânicos Voláteis , Metabolômica/métodos , Chá/química , Camellia sinensis/química , Compostos Orgânicos Voláteis/análise , Tricomas/química , Tricomas/metabolismo , Catequina/análise , Catequina/análogos & derivados , Catequina/metabolismo , Microextração em Fase Sólida , Folhas de Planta/química , Metaboloma , Flavonoides/análise
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