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1.
Biosens Bioelectron ; 234: 115366, 2023 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-37148802

RESUMEN

Due to their pivotal roles in many biological functions, cell surface proteins (CSPs) are often used for cancer prognosis, as evidenced by a number of studies that have reported significant changes in the expression levels of specific surface proteins depending on the stage of tumorigenesis and selection/variety of reprogrammed cells during cell fate conversion. Current CSP detection strategies suffer from poor selectivity and lack the ability for in situ analysis but maintain the spatial information between cells. Here, we have fabricated nanoprobes for surface-enhanced Raman scattering (SERS) immunoassays by conjugating a specific antibody onto silica-coated gold nanoparticles incorporating an individual Raman reporter (Au-tag@SiO2-Ab NPs) for highly sensitive and selective in situ detection in different types of cells. When multiple HEK293 cell lines stably expressing different levels of the CSP, ACE2, were investigated by the SERS immunoassay, we demonstrated that the level of ACE2 expression in each cell line could be statistically distinguished from that in the other cell lines, indicating the quantitative feature of this biosensing system. When detecting living cells without cell lysis or fixation, as well as fixed cells, the levels of the epithelial CSPs, EpCAM (epithelial cell adhesion molecule) and E-cadherin, were successfully determined using our Au-tag@SiO2-Ab NPs and SERS immunoassay system in a highly selective and quantitative manner without significant cytotoxicity. Hence, our work provides technical insight into the development of a biosensing platform for a variety of biomedical applications, such as cancer metastasis prognosis and the in situ monitoring of stem cell reprogramming and differentiation.


Asunto(s)
Técnicas Biosensibles , Nanopartículas del Metal , Neoplasias , Humanos , Proteínas de la Membrana , Oro , Dióxido de Silicio , Enzima Convertidora de Angiotensina 2 , Células HEK293 , Espectrometría Raman , Inmunoensayo
2.
Sensors (Basel) ; 23(4)2023 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-36850384

RESUMEN

This article describes chemical and physical parameters, including their role in the storage, trade, and processing of potatoes, as well as their nutritional properties and health benefits resulting from their consumption. An analysis of the share of losses occurring during the production process is presented. The methods and applications used in recent years to estimate the physical and chemical parameters of potatoes during their storage and processing, which determine the quality of potatoes, are presented. The potential of the technologies used to classify the quality of potatoes, mechanical and ultrasonic, and image processing and analysis using vision systems, as well as their use in applications with artificial intelligence, are discussed.


Asunto(s)
Dispositivos Ópticos , Solanum tuberosum , Inteligencia Artificial , Procesamiento de Imagen Asistido por Computador , Tecnología
3.
Ciênc. rural (Online) ; 52(10): e20210403, 2022. tab, graf
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1364724

RESUMEN

The plants physiological processes such as transpiration and photosynthetic efficiency are directly related to leaf area, which is difficult to quantify in a nondestructive manner. To generate a model to estimate the total leaf area of plants of banana cv. Vitória, simple and multiple linear regressions utilizing the length and width of the third leaf, the product of length and width of the third leaf, and the total number of leaves of 'Vitória' plants, were tested. The data to develop the model were obtained from 'Vitória' banana plants from different edafoclimatic conditions and management. The best performance of the model was obtained using stepwise multiple regression with r2=0.93 and r2= 0.94. Validation of the model resulted in an r2 of 0.74.


Processos fisiológicos das plantas como transpiração e eficiência fotossintética estão diretamente relacionados à área foliar, a qual é difícil quantificar de forma não destrutiva. Para gerar um modelo para estimar a área foliar total de plantas da cv. Vitória, foram testadas regressões lineares simples e múltiplas utilizando comprimento e largura da terceira folha, o produto comprimento e largura da terceira folha e número total de folhas. Os dados para desenvolver o modelo foram obtidos de cultivos com diferentes condições edafoclimáticas e de manejo. O melhor modelo foi obtido por meio de regressão múltipla stepwise com r2 = 0,93 e r2 = 0,94. A validação do modelo resultou em r2 de 0,74.


Asunto(s)
Hojas de la Planta/anatomía & histología , Musa/anatomía & histología , Genotipo , Análisis de Regresión
4.
Materials (Basel) ; 13(13)2020 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-32605042

RESUMEN

The static elastic modulus (Ec) and compressive strength (fc) are critical properties of concrete. When determining Ec and fc, concrete cores are collected and subjected to destructive tests. However, destructive tests require certain test permissions and large sample sizes. Hence, it is preferable to predict Ec using the dynamic elastic modulus (Ed), through nondestructive evaluations. A resonance frequency test performed according to ASTM C215-14 and a pressure wave (P-wave) measurement conducted according to ASTM C597M-16 are typically used to determine Ed. Recently, developments in transducers have enabled the measurement of a shear wave (S-wave) velocities in concrete. Although various equations have been proposed for estimating Ec and fc from Ed, their results deviate from experimental values. Thus, it is necessary to obtain a reliable Ed value for accurately predicting Ec and fc. In this study, Ed values were experimentally obtained from P-wave and S-wave velocities in the longitudinal and transverse modes; Ec and fc values were predicted using these Ed values through four machine learning (ML) methods: support vector machine, artificial neural networks, ensembles, and linear regression. Using ML, the prediction accuracy of Ec and fc was improved by 2.5-5% and 7-9%, respectively, compared with the accuracy obtained using classical or normal-regression equations. By combining ML methods, the accuracy of the predicted Ec and fc was improved by 0.5% and 1.5%, respectively, compared with the optimal single variable results.

5.
J Forensic Sci ; 65(1): 238-247, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31107554

RESUMEN

Thermal paper is widely used as a print medium for different applications but it constitutes a tricky substrate for fingermark visualization. An earlier work (J Forensic Sci 2015;60:1034) reported how to visualize fingermarks on untreated thermal paper by illuminating the item with a UV-A light source. In the present paper, the potential of the near infrared (NIR) luminescence has been tested on thermal paper compared to the mentioned method. A controlled study was carried out utilizing eccrine enriched fingermarks. The promising outcomes obtained were further confirmed by performing a pseudo-operational trial. Data clearly showed that the use of the NIR filter gave better results. Finally, preliminary tests suggested a different mechanism of reaction induced by fingermarks with respect to the one behind the thermal printing. Thus, NIR luminescence represents a refinement to the suite of optical examination processes, including the potential to increase the number of marks recovered in a noncontact, nondestructive way.

6.
J Food Prot ; 82(5): 796-803, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30986363

RESUMEN

The objective of this research was to apply near-infrared spectroscopy, with a short-wavelength range of 950 to 1,650 nm, for the rapid detection of aflatoxin B1 (AFB1) contamination in polished rice samples. Spectra were obtained by reflection mode for 105 rice samples: 90 samples naturally contaminated with AFB1 and 15 samples artificially contaminated with AFB1. Quantitative calibration models to detect AFB1 were developed using the original and pretreated absorbance spectra in conjunction with partial least squares regression with prediction testing and full cross-validation. The statistical model from the external validation process developed from the treated spectra (standard normal variate and detrending) was most accurate for prediction, with a correlation coefficient (r) of 0.952, a standard error of prediction of 3.362 µg/kg, and a bias of -0.778 µg/kg. The most predictive models according to full cross-validation were developed from the multiplicative scatter correction pretreated spectra (r = 0.967, root mean square error in cross-validation [RMSECV] = 2.689 µg/kg, bias = 0.015 µg/kg) and standard normal variate pretreated spectra (r = 0.966, RMSECV = 2.691 µg/kg, bias = 0.008 µg/kg). A classification-based partial least squares discriminant analysis model of AFB1 contamination classified the samples with 90% accuracy. The results indicate that the near-infrared spectroscopy technique is potentially useful for screening polished rice samples for AFB1 contamination.


Asunto(s)
Aflatoxina B1 , Análisis de los Alimentos , Oryza , Espectroscopía Infrarroja Corta , Aflatoxina B1/análisis , Calibración , Análisis de los Alimentos/instrumentación , Análisis de los Alimentos/métodos , Análisis de los Mínimos Cuadrados , Oryza/química
7.
Rev Environ Contam Toxicol ; 246: 65-89, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-29532252

RESUMEN

Persistent organic pollutants (POPs) are present in almost all environments due to their high bioaccumulation potential. Especially species that adapted to human activities, like gulls, might be exposed to harmful concentrations of these chemicals. The nature and degree of the exposure to POPs greatly vary between individual gulls, due to their diverse foraging behavior and specialization in certain foraging tactics. Therefore, in order clarify the effect of POP-contaminated areas on gull populations, it is important to identify the sources of POP contamination in individual gulls. Conventional sampling methods applied when studying POP contamination are destructive and ethically undesired. The aim of this literature review was to evaluate the potential of using feathers as a nondestructive method to determine sources of POP contamination in individual gulls. The reviewed data showed that high concentrations of PCBs and PBDEs in feathers together with a large proportion of less bioaccumulative congeners may indicate that the contamination originates from landfills. Low PCB and PBDE concentrations in feathers and a large proportion of more bioaccumulative congeners could indicate that the contamination originates from marine prey. We propose a nondestructive approach to identify the source of contamination in individual gulls based on individual contamination levels and PCB and PBDE congener profiles in feathers. Despite some uncertainties that might be reduced by future research, we conclude that especially when integrated with other methods like GPS tracking and the analysis of stable isotopic signatures, identifying the source of POP contamination based on congener profiles in feathers could become a powerful nondestructive method.


Asunto(s)
Aves , Contaminantes Ambientales/análisis , Plumas/química , Animales , Monitoreo del Ambiente , Agua de Mar
8.
Plant Reprod ; 30(4): 171-178, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29101473

RESUMEN

KEY MESSAGE: An easy and highly reproducible nondestructive method named the Leaf Collar Method is described to identify and characterize the different stages of pollen development in maize. In plants, many cellular events such as meiosis, asymmetric cell division, cell cycle regulation, cell fate determination, nucleus movement, vacuole formation, chromatin condensation and epigenetic modifications take place during pollen development. In maize, pollen development occurs in tassels that are confined within the internal stalk of the plant. Hence, identification of the different pollen developmental stages as a tool to investigate above biological processes is impossible without dissecting the entire plant. Therefore, an efficient and reproducible method is necessary to isolate homogeneous cell populations at individual stages throughout pollen development without destroying the plant. Here, we describe a method to identify the various stages of pollen development in maize. Using the Leaf Collar Method in the maize inbreed line B73, we have determined the duration of each stage from pollen mother cells before meiosis to mature tricellular pollen. Anther and tassel size as well as percentage of pollen stages were correlated with vegetative stages, which are easily recognized. The identification of stage-specific genes indicates the reproducibility of the method. In summary, we present an easy and highly reproducible nondestructive method to identify and characterize the different stages of pollen development in maize. This method now opens the way for many subsequent physiological, morphological and molecular analyses to study, for instance, transcriptomics, metabolomics, DNA methylation and chromatin patterns during normal and stressful conditions throughout pollen development in one of the economically most important grass species.


Asunto(s)
Polen/crecimiento & desarrollo , Zea mays/crecimiento & desarrollo , Botánica/métodos , Separación Celular , Perfilación de la Expresión Génica , Genes de Plantas , Hojas de la Planta/anatomía & histología , Polen/genética , ARN de Planta/aislamiento & purificación , Reacción en Cadena en Tiempo Real de la Polimerasa , Reproducibilidad de los Resultados , Zea mays/genética
9.
J Forensic Dent Sci ; 9(3): 157-164, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29657494

RESUMEN

INTRODUCTION: Age has been considered as a reliable marker for establishing the identity of a person in the field of forensic medicine. Teeth are useful skeletal indicators of age at death since it can survive for decades. Nondestructive methods ensure the evident preservation of dental hard tissues that reflect age changes from the cradle to the grave. Therefore, an attempt was made for estimating the age using the nondestructive method. AIMS AND OBJECTIVES: The aim of this study to assess whether physiological changes of the teeth allow possible correlation for accurate age estimation and to establish a graduation standard by microscopic observation for a better age correlation. MATERIALS AND METHODS: The study was carried on 209 teeth samples extracted for orthodontic treatment or periodontal diseases comprised both maxillary and mandibular teeth across different age groups. The assessment of these changes was carried out by well-established standard methods with some proposed modifications. RESULTS: Pearson correlation analyses revealed root dentin translucency with the highest correlation (r = 0.97) followed by periodontal ligament attachment (r = 0.95), root dentin color (r = 0.95), and attrition being the least correlated (r = 0.90). All the parameters taken for the study contributed to stepwise linear regression analysis (R = 0.98; P < 0.01) indicating a strongly positive relationship between age and the changes observed. A regression formula was obtained with mean error age difference ±1.0 years. CONCLUSION: The present study showed that extracted tooth is highly significant in identifying the age without being sectioned or further processed and also signifies the use of microscope for observation of these changes, thus reducing the errors of calibrating the age.

10.
J Agric Food Chem ; 64(40): 7658-7666, 2016 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-27653674

RESUMEN

In red grape berries, anthocyanins account for about 50% of the skin phenols and are responsible for the final wine color. Individual anthocyanin levels and compositional profiles vary with cultivar, maturity, season, region, and yield and have been proposed as chemical markers to differentiate wines and to provide valuable information regarding the adulteration of musts and wines. A fast, easy, solvent-free, nondestructive method based on visible, short-wave, and near-infrared hyperspectral imaging (HSI) in intact grape berries to fingerprint the color pigments in eight different grape varieties was developed and tested against HPLC. Predictive models based on modified partial least-squares (MPLS) were built for 14 individual anthocyanins with coefficients of determination of cross-validation (R2CV) ranging from 0.70 to 0.93. For the grouping of total and nonacylated anthocyanins, external validation was conducted with coefficient of determination of prediction (R2P) of 0.86. HSI could potentially become an alternative to HPLC with reduced analysis time and labor costs while providing reliable and robust information on the anthocyanin composition of grape berries.


Asunto(s)
Antocianinas/análisis , Análisis de los Alimentos/métodos , Espectrofotometría/métodos , Vitis/química , Calibración , Frutas/química , Análisis de los Mínimos Cuadrados , Imagen Molecular/métodos , Reproducibilidad de los Resultados
11.
Arch Med Sadowej Kryminol ; 66(1): 65-70, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-28155989

RESUMEN

Commonly used destructive DNA isolation techniques consist of pulverization which leads to the complete destruction of smaller bones or irreversible damage to larger bones through the cutting of extensive fragments. The procedure is totally unacceptable when handling bones which are valuable for anthropological or religious reasons, as museum exhibits or due to emotional factors. Since the Department's team has already resolved this problem in the case of human teeth (A. Pilecka), efforts have been undertaken to develop a similar non-destructive technique for the isolation of DNA from human bones. To the best knowledge of the authors of the report, the study has yielded the world's first STR profile derived from DNA isolated from human bones by a technique that is non-destructive toward the bone surface.


Asunto(s)
Médula Ósea/metabolismo , Huesos/metabolismo , ADN/análisis , ADN/aislamiento & purificación , Medicina Legal/métodos , Humanos , Manejo de Especímenes
12.
Ciênc. rural ; 45(8): 1432-1438, 08/2015. tab, graf
Artículo en Portugués | LILACS | ID: lil-753088

RESUMEN

As propriedades mecânicas por flexão estática da madeira resinada de Pinus elliottii foram avaliadas por meio de testes destrutivos e não destrutivos. Para tanto, foram confeccionados corpos de prova de 10x10x200mm3 (radial, tangencial e longitudinal), levando em consideração dois fatores: lenho (juvenil, próximo à medula e adulto, próximo à casca) e resina, isto é, corpos de prova oriundos de toras com e sem estrias de resinagem. Para a avaliação não destrutiva, utilizou-se um aparelho de ultrassom com transdutores do tipo ponto seco, em que se pode calcular a velocidade da onda ultrassônica e consequentemente o módulo de elasticidade dinâmico (ED). Para obtenção do módulo de elasticidade (MOE) e do módulo de ruptura (MOR), realizou-se o ensaio destrutivo de flexão estática de três pontos. De posse das curvas de força x deformação, calculou-se a fragilidade do material. Os resultados confirmaram que o fator lenho foi significativo para as propriedades analisadas e o fator resina, em especial, para aumento do MOR e da massa específica. A fragilidade aumentou quando analisada a madeira juvenil e o fator resina quando incluso tendeu a aumentar a fragilidade no lenho adulto. O modelo de regressão múltiplo com variáveis Dummies, proposto para estimar o MOE pelo ED, foi significativo em 1% de probabilidade de erro (r2=0,75). Os resultados apresentados no presente trabalho mostraram que os fatores lenho e resina não afetaram negativamente as propriedades mecânicas da madeira de Pinus elliottii, em que, para o segundo fator, conclui-se, de maneira geral, que a madeira serrada oriunda de toras resinadas pode não representar danos significativos quando em serviço estrutural.


The mechanical properties for static bending of Pinus elliottii tapped wood were evaluated by nondestructive and destructive tests. To achieve this, samples measuring 10x10x200mm3 (thickness, width and length) were prepared considering two factors: wood (juvenile, near to pith and mature, near to bark) and rosin, i.e., samples from logs with and without tapping grooves. The nondestructive evaluation were performed using an ultrasound equipment with dry-point transducers in order to measure the ultrasonic velocity and, consequently, the dynamic modulus of elasticity (ED). The modulus of elasticity (MOE) and the modulus of rupture (MOR) were measured through static bending tests. The wood brittleness were determined through the analysis of force x deformation plots. The results confirmed the significance of wood factor for the properties analyzed and the factor rosin, especially for MOR and density. The brittleness increased for the juvenile wood and, when included the factor rosin, this property tends to increase for the mature wood. The multiple regression model with Dummies variables proposed to estimate MOE as a function of ED was significant at 1% of probability of error (r2=0.75). Moreover, the results showed that factor wood and factor rosin did not negatively affect the mechanical properties of Pinus elliotti wood. In general, the timber from tapped logs could not represent significant damages when in structural service.

13.
Ciênc. rural ; 43(4): 616-622, abr. 2013. ilus, tab
Artículo en Portugués | LILACS | ID: lil-669357

RESUMEN

O trabalho teve por objetivo estimar o módulo de elasticidade estático da madeira termorretificada de Pinus taeda por meio do método não destrutivo ultrassônico. Foram confeccionados 93 corpos de prova das pranchas de pinus com dimensões de 2,5x2,5x41,0cm (espessura, largura e comprimento). Avaliaram-se corpos de prova submetidos a dois tratamentos térmicos denominados Combinação e Estufa, além daqueles sem tratamento térmico. No tratamento de combinação, as peças foram termorretificadas em autoclave a 130ºC±3°C e pressão de 2kgf cm-², por 3 horas e, após um período de condicionamento, aquecidas em estufa elétrica a 160°C±1°C, pelo mesmo período. Já as peças destinadas apenas ao tratamento em estufa foram submetidas à última condição. Os modelos matemáticos criados apresentaram r2 entre 0,48 e 0,66, sendo significativos em 1% de probabilidade de erro. Dessa forma, com o aprimoramento de metodologias de ensaios não destrutivos ultrassônicos, a presente técnica pode ser útil e eficiente para estimar o módulo de elasticidade estático da madeira de Pinus taeda.


This study aimed to estimate the modulus of elasticity of Pinus taeda thermally modified wood by ultrasonic nondestructive method. To achieve this, 93 samples with dimensions 2.5x2.5x41.0cm (thickness, width and length) from pine boards were prepared. The wood samples were thermally modified through two distinct treatments (Combination and Oven). The Combination treatment was performed in an autoclave at 130ºC±3°C and pressure of 2kgf cm-2 for 3 hours. After a period of conditioning, the wood samples were heated in an electric oven 160°C±1°C for the same time. On the other hand, wood samples of the Oven treatment was modified with only last condition. The mathematical models showed r2 between 0.48 and 0.66 and significance at 1% of probability of error. Thus, improvement of ultrasonic nondestructive tests shows that technique could be useful and efficient in order to estimate modulus of elasticity of Pinus taeda wood.

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