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A data fusion strategy based on hyperspectral imaging (HSI) and electronic nose (e-nose) systems was developed in this study to inspect the postharvest ripening process of Hayward kiwifruit. The extracted features from the e-nose and HSI techniques, in single or combined mode, were used to develop machine learning algorithms. Performance evaluations proved that the fusion of olfactory and reflectance data improves the performance of discriminative and predictive algorithms. Accordingly, with high classification accuracies of 100% and 94.44% in the calibration and test stages, the data fusion-based support vector machine (SVM) outperformed the partial least square discriminant analysis (PLSDA) for discriminating the kiwifruit samples into eight classes based on storage time. Moreover, the data fusion-based support vector regression (SVR) was a better predictor than partial least squares regression (PLSR) for kiwifruit firmness, soluble solids content (SSC), and titratable acidity (TA) measures. The prediction R 2 and RMSE criteria of the SVR algorithm on the test data were 0.962 and 0.408 for firmness, 0.964 and 0.337 for SSC, and 0.955 and 0.039 for TA, respectively. It was concluded that the hybrid of e-nose and HSI systems coupled with the SVM algorithm delivers an effective tool for accurate and nondestructive monitoring of kiwifruit quality during storage.

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Soil pollution with heavy metals is a serious threat to the environment. However, soils polluted with heavy metals are considered good sources of native metal-resistant Trichoderma strains. Trichoderma spp. are free-living fungi commonly isolated from different ecosystems, establishing endophytic associations with plants. They have important ecological and biotechnological roles due to their production of a wide range of secondary metabolites, thus regulating plant growth and development or inducing resistance to plant pathogens. In this work we used indigenous Trichoderma strains that were previously isolated from different soil types to determine their tolerance to increased copper and nickel concentrations as well as mechanisms of metal removal. The concentrations of bioavailable metal concentrations were determined after extraction with diethylene-triamine pentaacetate (DTPA)-extractable metals (Cd, Cr, Co, Cu, Pb, Mn, Ni, and Zn) from the soil samples by inductively coupled plasma-optical emission spectrometry (ICP-OES). Two indigenous T. harzianum strains were selected for copper tolerance, and three indigenous T. longibrachiatum strains were selected for nickel tolerance tests. Strains were isolated from the soils with the highest and among the lowest DTPA-extractable metal concentrations to determine whether the adaptation to different concentrations of metals affects the mechanisms of remediation. Mechanisms of metal removal were determined using Fourier-transform infrared spectroscopy (FTIR) and X-ray fluorescence spectroscopy (XRF), non-destructive methods characterized by high measurement speed with little or no need for sample preparation and very low costs. Increased DTPA-extractable metal content for nickel and copper was detected in the soil samples above the target value (TV), and for nickel above the soil remediation intervention values (SRIVs), for total metal concentrations which were previously determined. The SRIV is a threshold of metal concentrations indicating a serious soil contamination, thus confirming the need for soil remediation. The use of FTIR and XRF methods revealed that the presence of both biosorption and accumulation of metals in the Trichoderma cells, providing good bioremediation potential for Ni and Cu.

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Siamese bat catfish (Oreoglanis siamensis Smith, 1993) has been listed as an endangered species, and its abundance has been severely declining due to habitat degradation and overfishing. To establish an appropriate management strategy, it is crucial to gain information about the distribution of this endangered species. As O. siamensis live under rocks in streams, detecting their presence is difficult. Recently, environmental DNA (eDNA)-based detection has been demonstrated to be a valid tool for monitoring rare species, such as O. siamensis. Therefore, this study developed an eDNA assay targeting a 160 bp fragment of the COI region to detect the presence of this species in its natural habitat. An amount of 300 mL of water samples (0.7 µm filtered) were collected from 15 sites in the Mae Klang sub-basin, where this fish species was visually detected at two locations. O. siamensis eDNA was detected at 12 of the 15 sites sampled with varying concentrations (0.71-20.27 copies/mL), including at the sites where this species was visually detected previously. The developed O. siamensis eDNA assay was shown to be effective for detecting the presence of this endangered species in the Klang Phat and Klang Rivers within the Doi Inthanon National Park.

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Owing to their health-boosting properties and other appreciable properties, citrus fruit is widely consumed and commercialized worldwide. Destination markets around the world vary in their fruit quality requirements and are also highly influenced by climatic conditions, agronomical and postharvest practices. Hence, harvesting decisions are arduous. Maturity indices in citrus fruit are highly variable and dependent on the species and varieties, growing regions, and destination markets. For decades, determination of the maturity of citrus fruit and predicting the near time of harvesting was a challenge for producers, researchers, and food safety agencies. Thus, the current review provides a correlation between maturity and internal components and an overview of techniques of maturity determination for citrus fruits. Also, stress has been given to the destructive and nondestructive methods to determine the maturity level of different citrus species. The techniques presented in this review portray continuous productiveness as an excellent quality assessment, particularly as ripening and maturity analysis tools for citrus fruits. Traditional techniques are time-consuming, laborious, costly, destructive, and tedious. Thus, these nondestructive techniques hold great potential to replace conventional procedures.

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Cocoa (Theobroma cacao L.) and its derivatives are appreciated for their aroma, color, and healthy properties, and are commodities of high economic value worldwide. Wide ranges of conventional methods have been used for years to guarantee cocoa quality. Recently, however, demand for global cocoa and the requirements of sensory, functional, and safety cocoa attributes have changed. On the one hand, society and health authorities are increasingly demanding new more accurate quality control tests, including not only the analysis of physicochemical and sensory parameters, but also determinations of functional compounds and contaminants (some of which come in trace quantities). On the other hand, increased production forces industries to seek quality control techniques based on fast, nondestructive online methods. Finally, an increase in global cocoa demand and a consequent rise in prices can lead to future cases of fraud. For this reason, new analytes, technologies, and ways to analyze data are being researched, developed, and implemented into research or quality laboratories to control cocoa quality and authenticity. The main advances made in destructive techniques focus on developing new and more sensitive methods such as chromatographic analysis to detect metabolites and contaminants in trace quantities. These methods are used to assess cocoa quality; study new functional properties; control cocoa authenticity; or detect frequent emerging frauds. Regarding nondestructive methods, spectroscopy is the most explored technique, which is conducted within the near infrared range, and also within the medium infrared range to a lesser extent. It is applied mainly in the postharvest stage of cocoa beans to analyze different biochemical parameters or to assess the authenticity of cocoa and its derivatives.

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The paper describes an experiment focusing on the way the material system influences the bond strength of large-format tiles installed on concrete substrate during mechanical loading under conditions that correspond to real-life application. This involves a controllable mechanical load applied over an area of a test model while observing its condition using non-destructive methods (ultrasonic pulse velocity test, acoustic emission method, strain measurement, and acoustic tracing). The model consisted of a concrete slab onto which were mounted four different systems with large-format tiles with the dimensions of 3 m × 1 m. The combinations differed in the thickness of the tile, the adhesive, and whether or not a fabric membrane was included in the adhesive bed. The experiment showed that the loading caused no damage to the ceramic tile. All the detected failures took place in the adhesive layer or in the concrete slab.

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Fiber-cement building products are increasingly used in construction. They are used as building and finishing material for facades, internal walls and roofs. Numerous advantages such as relatively low weight, low absorbability and relatively high strength allow to use these materials in bulky constructions and in buildings which are commonly considered tall. Safety reasons, however, point to the need to control the condition of materials used to erect such structures. It is also in line with the more and more widely implemented concept of monitoring the state of the structure and its components over their entire period of use (SHM). The article presents the results of experimental tests on flexural strength of cement-fiber boards in an air-dry state, which have been soaked in water for 24 hours and subjected to high temperature. The paper also presents a possibility to use a non-invasive method of acoustic emission and wavelet analysis for testing cement boards reinforced with cellulose fibers. Obtained results allow to track the change of mechanical parameters in boards subjected to environmental and exceptional factors. These results also confirm the applicability of the presented methods as instruments for observing the condition of the panels used.

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This study aimed to use chemometrics to evaluate the influence of lipid and protein oxidation on the color and texture characteristics of Brazilian dry-cured loin (Socol, BDL). Upon exploration using hierarchical cluster analysis (HCA), two clusters were formed, indicating that higher water activity (aw) was associated with higher lipid and protein oxidation. However, this fact was associated with softening and low color quality (a*, chroma, and cured color). In a more in-depth exploration, using principal component analysis (PCA) for each cluster separately, connections between protein and lipid oxidation were found in high aw, as demonstrated by their statistical association. In the same way, relationships between high hardness and carbonyl contents were obtained only in high aw. In addition, an overall relationship (p < 0.05) between nondestructive measurements, such as hardness, and destructive methods (malonaldehyde and carbonyl contents) demonstrate that nondestructive techniques can be promising for further studies in the method replacement field. In this study, reasonable explanations of the connections between oxidative damage and quality traits in Socol are provided.

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Hydrogels are extensively used for tissue engineering, cell therapy or controlled release of bioactive factors. Nondestructive techniques that can follow their viscoelastic properties during polymerization, remodeling, and degradation are needed, since these properties are determinant for their in vivo efficiency. In this work, we proposed the viscoelastic testing of bilayered materials (VeTBiM) as a new method for nondestructive and contact-less mechanical characterization of soft materials. The VeTBiM method measures the dynamic displacement response of a material, to a low amplitude vibration in order to characterize its viscoelastic properties. We validated VeTBiM by comparing data obtained on various agar and chitosan hydrogels with data from rotational rheometry, and compression tests. We then investigated its potential to follow the mechanical properties of chitosan hydrogels during gelation and in the presence of papain and lysozyme that induce fast or slow enzymatic degradation. Due to this nondestructive and contactless approach, samples can be removed from the instrument and stored in different conditions between measurements. VeTBiM is well adapted to follow biomaterials alone or with cells, over long periods of time. This new method will help in the fine tuning of the mechanical properties of biomaterials used for cell therapy and tissue engineering. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 2565-2573, 2017.

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ABSTRACT: The leaf area determination are extremely important in agronomic and physiological studies, as they provide valuable information in vegetable metabolism, methods used for this purpose should be accurate. This study aimed to develop polynomial models to estimate leaf area (LA). The methods used were leaf discs and ImageJ(r) software, with measures of length (L), width (W), and relationship between length times width (LW) in leaves of the bell pepper crop in two field trials with two hybrids: Arcade and Impacto, as well as, the correlation of values found when using the two methods. Through a random sampling, 560 leaves from each hybrid were selected, at different stages of crop growth. Regression analysis of LA versus measures L, W and LW were performed by linear and quadratic models. The variable that best estimated LA was the relationship between LW with linear model (r2=0.98). Measurements of length and width of leaves presented adjustment to quadratic model r2=0.93 and r2=0.91, respectively. The integrator model for all samples and both hybrids was: LA=0.57×LW. The destructive method of leaf discs showed high correlation (r2=0.99) with the non-destructive method of ImageJ(r) software.

RESUMO: A determinação da área foliar é importante, em estudos agronômicos e fisiológicos, para a obtenção de informações sobre o metabolismo vegetal e as técnicas utilizadas devem ser simples. O objetivo deste estudo foi desenvolver modelos polinomiais para estimar a área foliar (AF). Foram utilizados os métodos de discos foliares e software ImageJ, com as medidas do comprimento (C) e da largura (L), e a relação entre o comprimento vezes a largura (CL) em folhas da cultura do pimentão, em dois ensaios com dois híbridos, Arcade e Impacto, e correlacionar os valores encontrados pelos dois métodos. Através de amostragem aleatória simples, foram selecionadas 560 folhas de cada híbrido, em diferentes estágios de crescimento da cultura. A análise de regressão da área foliar versus as medidas de C, L e CL foi realizada por modelos lineares e quadráticos. A variável que melhor estimou a AF foi a relação entre o CL, pelo modelo linear com r2=0,98. As medidas do comprimento e da largura das folhas apresentou ajustamento do modelo quadrática de r2=0,93 e r2=0,91, respectivamente. O modelo integrador de todas as amostras, para ambos os híbridos, foi: AF=0,57×CL. O método destrutivo por discos mostrou alta correlação (r2=0,99) com o método não destrutivo pelo ImageJ.

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For many years, scientists have been searching for nondestructive methods for the measurement of plant root system parameters. The measurement of electrical capacitance (EC) across the root has been proposed as one such nondestructive method. This article presents a study on the determination of relationships between EC measurement and the shape and size of the electrodes immersed in medium that are used for measurement. Measurement of EC and the parameters characterizing root systems of 1-year-old seedlings of the common beech Fagus sylvatica L. was conducted under laboratory conditions. The measurements of EC were performed between seedling root systems and two different electrodes in the form of a cylinder or a rectangular plate. Statistically significant correlations were found between the capacitance and root system parameters in both the variants; however, the correlations were higher in the case of the flat rectangular plate. Correlation coefficient (r) between EC and total root length was  0.688 for cylindrical electrode and  0.802 for rectangular plate, for total root area 0.641 and 0.818, and for dry weight of root system 0.502 and 0.747. The best-fitted linear regression relationships between the EC and the measured parameters were characterized by low determination coefficients in variants with cylindrical electrodes, and higher with flat rectangular plate electrodes. The results indicated that a two-dielectric media concept is a better model than Dalton's model when attempting to interpret the behavior of root and soil capacitance. The different electrodes probably allow root capacitance measurements to be interpreted from different aspects. However, this hypothesis requires further verification.

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BACKGROUND: In cell-based therapies, in vitro studies on biomimetic cell-scaffold constructs can facilitate the determination of the cell dose, a key factor in guaranteeing the effectiveness of the treatment. However, highly porous scaffolds do not allow a nondestructive evaluation of the cell number. Our objective was to develop a nondestructive method for human mesenchymal stem cells dose evaluation in a highly porous scaffold for bone regeneration. MATERIALS & MEASUREMENT METHOD: Proliferation trend of human mesenchymal stem cells on Biocoral® scaffolds was measured by a resazurin-based assay here optimized for 3D cultures. The method allows to noninvasively follow the cell proliferation on biocorals over 3 weeks with very high reproducibility. CONCLUSION: This reliable method could be a powerful tool in cell-based therapies for cell dose determination.