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Artificial neural network and kinetic modeling of capers during dehydration and rehydration processes
No full textThis study aimed to investigate the drying kinetics of capers at different temperatures and to examine the morphological changes of capers during the drying and rehydration processes. Computer-aided image processing and Artificial Neural Network models (ANN) were used to analyze the shrinkage and moisture ratio of capers (drying) and the expansion of capers (rehydration). Lewis, Page, Fick's law, and logarithmic models were investigated to describe the conventional drying kinetics of capers at 50, 60, and 70 degrees C; the logarithmic model was shown to be the best describing model (r(2): 0.9996, 0.9996 and 0.9981, respectively). Effective diffusivities varied between 1.91 x 10(-10) and 2.62 x 10(-10) m(2)/s for the temperature range. The activation energy was 14.572 kJ/mol. Image processing revealed that diameter reduction rates were 1 x 10(-4) mm/s for 50 and 70 & DEG;C and 7 x 10(-5) mm/s for 60 degrees C. ANN was applied using multilayer perceptron models with three layers (input: ANN1, hidden: ANN2, and output: ANN3) which were sufficiently valid for predicting the experimental parameters (r(2): 0.9992, 0.9915, and 0.8484, respectively). All morphological properties were reduced with drying, and shrinkage of capers was increased proportionally with the moisture content. The Global Sensitivity Analysis recognized treatment time as the most influential parameter affecting the moisture ratio and the caper diameter changes. Practical applications One of the major problems for humans has been to improve food preservation techniques for long-term storage. The major scope of industry is the drying of fruits and/or vegetables to produce dried foods with high quality and a long shelf life. To the best of our knowledge, drying of capers regarding the drying kinetics, modeling and quality changes has not been published to date. In this study, goal was to better understand drying kinetics and geometric changes that occur to capers during the dehydration and rehydration processes at various drying temperatures. Quantitative information regarding geometrical changes to capers was supplied by the image processing of the acquired pictures, which enabled rapid monitoring of physical changes during dehydration and rehydration. The remarked kinetic model, ANN model, and Quantitative information regarding geometrical changes are valuable information for researchers studying on drying of food and large-scale dryer designers
Artificial Neural Network Prediction of Antiadhesion and Antibiofilm-Forming Effects of Antimicrobial Active Mushroom Extracts on Food-Borne Pathogens
No full textThe problem of microbial biofilms has come to the fore alongside food, pharmaceutical, and healthcare industrialization. The development of new antibiofilm products has become urgent, but it includes bioprospecting and is time and money-consuming. Contemporary efforts are directed at the pursuit of effective compounds of natural origin, also known as "green" agents. Mushrooms appear to be a possible new source of antibiofilm compounds, as has been demonstrated recently. The existing modeling methods are directed toward predicting bacterial biofilm formation, not in the presence of antibiofilm materials. Moreover, the modeling is almost exclusively targeted at biofilms in healthcare, while modeling related to the food industry remains under-researched. The present study applied an Artificial Neural Network (ANN) model to analyze the anti-adhesion and anti-biofilm-forming effects of 40 extracts from 20 mushroom species against two very important food-borne bacterial species for food and food-related industries-Listeria monocytogenes and Salmonella enteritidis. The models developed in this study exhibited high prediction quality, as indicated by high r(2) values during the training cycle. The best fit between the modeled and measured values was observed for the inhibition of adhesion. This study provides a valuable contribution to the field, supporting industrial settings during the initial stage of biofilm formation, when these communities are the most vulnerable, and promoting innovative and improved safety management
Advanced photocatalysis mediated by TiO2/Ag/TiO2 nanoparticles modified cotton fabric
No full textNovel cotton-based TiO2/Ag/TiO2 nanocomposites for wastewater treatment were developed by fine chemical synthesis path with the goal of coping with wastewater issues and environmental remediation. The photocatalytic performances of nanocomposites were tested during photodegradation processes of RB, AO7 and MR under simulated solar light. Double- and single-loaded nanocomposites were synthesized by a simple bottom-up approach implying in situ photoreduction of Ag+ ions on the surface of TiO2 NPs previously deposited on cotton fibers from colloids. The spherical-like colloidal TiO2 NPs (4.5 nm) and TiO2/Ag NPs (8 nm) and the formation of uniform TiO2/Ag and TiO2/Ag/TiO2 nano-coatings on cotton fibers were examined by TEM and FESEM. The reduction of Ag+ ions on TiO2 surface was undoubtedly proven by the appearance of SPR band of Ag NPs in UV/Vis spectra. Raman spectroscopy clearly confirmed the presence of anatase TiO2 in nanocomposites. Quantitative determination of TiO2 and Ag in nanocomposites was accomplished using EDX and ICP-OES. The cotton-based TiO2/Ag/TiO2 nanocomposite showed the highest photocatalytic efficiency (> 90%) and maintained its removal efficiency after three reuse cycles, indicated its exceptional photochemical ability. The initial idea of improved photocatalytic performances of a TiO2 NPs double-layer with immobilized Ag NPs was justified as the TiO2/Ag/TiO2 processed sample contributed additional binding sites for dye molecules. Considering that the photocatalytic activity of the cotton-based TiO2 and TiO2/Ag samples was practically imperceptible, it can be assumed that the synthesized Ag NPs act predominantly as electron traps in the double-loaded synthesized system
Screening of Antifungal Activity of Essential Oils in Controlling Biocontamination of Historical Papers in Archives
No full textThe main challenge in controlling the microbiological contamination of historical paper is finding an adequate method that includes the use of cost-effective, harmless, and non-toxic biocides whose effectiveness is maintained over time and without adverse effects on cultural heritage and human health. Therefore, this study demonstrated the possibility of using a non-invasive method of historical paper conservation based on plant essential oils (EOs) application. Evaluation of antimicrobial effects of different EOs (lemongrass, oregano, rosemary, peppermint, and eucalyptus) was conducted against Cladosporium cladosporoides, Aspergillus fumigatus, and Penicillium chrysogenum, which are commonly found on archive papers. Using a mixture of oregano, lemongrass and peppermint in ratio 1:1:1, the lower minimal inhibition concentration (0.78%) and better efficiency during a vapour test at the highest tested distance (5.5 cm) compared with individual EOs was proven. At the final step, this EOs mixture was used in the in situ conservation of historical paper samples obtained from the Archives of Vojvodina. According to the SEM imaging, the applied EOs mixture demonstrates complete efficiency in the inhibition of fungi colonization of archive papers, since fungal growth was not observed on samples, unlike the control samples
Sustainable non-woven sorbents based on jute post-industrial waste for cleaning of oil spills
No full textIntensified oil exploitation accompanied with frequent oil spills having a detrimental impact on ecosystems are seeking efficient, environmentally and economically feasible solutions. In an attempt to develop an efficient, reusable, biodegradable and cheap sorbent for oil clean-up non-woven sorbents based on recycled jute postindustrial textile waste were fabricated. The influence of area density of non-woven sorbents and hydrophobicity of fibers on overall oil sorption performance was the focus of this research. All sorbents showed a good reusability after five sorption cycles and buoyancy in water even after 24 h independently of sorbent structure. The area density of sorbents and viscosity of studied oils (crude oil, diesel oil and two types of motor oils) highly affected the oil sorption capacity and oil retention. The sorbent with the lowest area density exhibited the best oil sorption performance. The esterification of jute with stearic fatty acid contributed to decrease in water uptake of sorbents but also to negligible change of oil sorption behavior indicating that the structure of the sorbent in this case plays a crucial role
Comparison of Different Machine Learning Models for Modelling the Higher Heating Value of Biomass
No full textThe aim of this study was to investigate the potential of using structural analysis parameters for estimating the higher heating value (HHV) of biomass by obtaining information on the composition of cellulose, lignin, and hemicellulose. To achieve this goal, several nonlinear mathematical models were developed, including polynomials, support vector machines (SVMs), random forest regression (RFR) and artificial neural networks (ANN) for predicting HHV. The performed statistical analysis “goodness of fit” showed that the ANN model has the best performance in terms of coefficient of determination (R2 = 0.90) and the lowest level of model error for the parameters X2 (0.25), RMSE (0.50), and MPE (2.22). Thus, the ANN model was identified as the most appropriate model for determining the HHV of different biomasses based on the specified input parameters. In conclusion, the results of this study demonstrate the potential of using structural analysis parameters as input for HHV modeling, which is a promising approach for the field of biomass energy production. The development of the model ANN and the comparative analysis of the different models provide important insights for future research in this field
The Role of Isoflavones in the Prevention of Breast Cancer and Prostate Cancer
No full textThis narrative review summarizes epidemiological studies on breast cancer and prostate cancer with an overview of their global incidence distribution to investigate the relationship between these diseases and diet. The biological properties, mechanisms of action, and available data supporting the potential role of isoflavones in the prevention of breast cancer and prostate cancer are discussed. Studies evaluating the effects of isoflavones in tissue cultures of normal and malignant breast and prostate cells, as well as the current body of research regarding the effects of isoflavones attained through multiple modifications of cellular molecular signaling pathways and control of oxidative stress, are summarized. Furthermore, this review compiles literature sources reporting on the following: (1) levels of estrogen in breast and prostate tissue; (2) levels of isoflavones in the normal and malignant tissue of these organs in European and Asian populations; (3) average concentrations of isoflavones in the secretion of these organs (milk and semen). Finally, particular emphasis is placed on studies investigating the effect of isoflavones on tissues via estrogen receptors (ER)
ZnMn2O4 as a Cathode Material in an Aqueous Solution of ZnCl2 and Mn(NO3)2 for Zn-ion Batteries
No full textDue to Li-ion batteries having become the main power source of most portable electronic devices, their waste has also become a significant environmental problem. To find batteries that would be environmentally friendly, this work examines Zn-ion batteries in an aqueous solution of ZnCl2. The ZnMnO4 was synthesized by glycine nitrate combustion of Zn(NO3)2, Mn(NO3)2 and glycine as a chelating agent [1]. The structure of the material obtained was characterized by X-ray powder diffraction (XRPD) showing a spinel structure; the morphology was characterized by scanningelectron microscopy (SEM) showing that nano-particles were obtained. The electrochemical characterization was done by cyclic voltammetry in an aqueous solution of ZnCl2. The mixture pasted on the glossy carbon electrode was prepared by mixing the cathode material, graphite and polyvinyl diene difluoride (PVDF) in a ratio 85:10:5 [2]. Due to the low discharge capacity obtained of ~14 mAh g-1 for 5 mV s-1 , further examination was done by adding 1 ml of 1M Mn(NO3)2 into 10ml of a saturated aqueous solution of ZnCl2. After adding the Mn(NO3)2 , the dischargecapacity increased from ~14 mAh g-1 to ~65 mAh g-1 at the same polarization rate, making this additive a promising one for aqueous Zn-ion batteries. Further investigation needs to be directed to adding the same additive in larger amounts compared to 1ml to the same volume of the electrolyte. The results obtained suggest the aqueous Zn-ion battery described in this work to be a potentially promising “green” battery that may replace harmful commercial organic Li-ion batteries
