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Records Added in June 2021
Records added in June 2021
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Showing records 1 to 25 of 101. [First] Page: 1 2 3 4 5 Last
Design Strategies for Oxy-Combustion Power Plant Captured CO2 Purification
Ikenna J. Okeke, Tia Ghantous, Thomas A. Adams II
June 28, 2021 (v1)
Keywords: Aspen Plus, Carbon Dioxide Capture, CO2 Purification, Oxy-combustion, Petroleum Coke
This submission contains Aspen Plus files for the design and systems performance analysis of oxy-combustion power plant captured CO2 purification using different techniques.
Design, Overproduction and Purification of the Chimeric Phage Lysin MLTphg Fighting against Staphylococcus aureus
Feng Wang, Xiaohang Liu, Zhengyu Deng, Yao Zhang, Xinyu Ji, Yan Xiong, Lianbing Lin
June 29, 2021 (v1)
Subject: Biosystems
Keywords: antibiotic-resistant bacteria, antimicrobial drug, bacteriophage, bioengineering, biotechnology, endolysin, pathogen control, Staphylococcus aureus
With the increasing spread of multidrug-resistant bacterial pathogens, it is of great importance to develop alternatives to conventional antibiotics. Here, we report the generation of a chimeric phage lysin, MLTphg, which was assembled by joining the lysins derived from Meiothermus bacteriophage MMP7 and Thermus bacteriophage TSP4 with a flexible linker via chimeolysin engineering. As a potential antimicrobial agent, MLTphg can be obtained by overproduction in Escherichia coli BL21(DE3) cells and the following Ni-affinity chromatography. Finally, we recovered about 40 ± 1.9 mg of MLTphg from 1 L of the host E. coli BL21(DE3) culture. The purified MLTphg showed peak activity against Staphylococcus aureus ATCC6538 between 35 and 40 °C, and maintained approximately 44.5 ± 2.1% activity at room temperature (25 °C). Moreover, as a produced chimera, it exhibited considerably improved bactericidal activity against Staphylococcus aureus (2.9 ± 0.1 log10 reduction was observed upon 40 nM MLTphg... [more]
From Cardoon Lignocellulosic Biomass to Bio-1,4 Butanediol: An Integrated Biorefinery Model
Isabella De Bari, Aristide Giuliano, Maria Teresa Petrone, Giovanni Stoppiello, Vittoria Fatta, Cecilia Giardi, Francesco Razza, Alessandra Novelli
June 29, 2021 (v1)
Keywords: 2G sugars, BDO, bioeconomy, integrated biorefinery, lignocellulosic biomass
Biorefineries are novel, productive models that are aimed at producing biobased alternatives to many fossil-based products. Biomass supply and overall energy consumptions are important issues determining the overall biorefinery sustainability. Low-profit lands appear to be a potential option for the sustainable production of raw materials without competition with the food chain. Cardoon particularly matches these characteristics, thanks to the rapid growth and the economy of the cultivation and harvesting steps. An integrated biorefinery processing 60 kton/y cardoon lignocellulosic biomass for the production of 1,4-butanediol (bio-BDO) is presented and discussed in this work. After designing the biorefinery flowsheet, the mass and energy balances were calculated. The results indicated that the energy recovery system has been designed to almost completely cover the entire energy requirement of the BDO production process. Despite the lower supply of electricity, the energy recovery syste... [more]
Biosorption: A Review of the Latest Advances
Enrique Torres
June 29, 2021 (v1)
Subject: Materials
Keywords: bioaccumulation, biocomposite, Biomass, biosorption, dyes, emerging organic contaminants, metals, pollutants
Biosorption is a variant of sorption techniques in which the sorbent is a material of biological origin. This technique is considered to be low cost and environmentally friendly, and it can be used to remove pollutants from aqueous solutions. The objective of this review is to report on the most significant recent works and most recent advances that have occurred in the last couple of years (2019−2020) in the field of biosorption. Biosorption of metals and organic compounds (dyes, antibiotics and other emerging contaminants) is considered in this review. In addition, the use and possibilities of different forms of biomass (live or dead, modified or immobilized) are also considered.
Extreme Learning Machine Based on Firefly Adaptive Flower Pollination Algorithm Optimization
Ting Liu, Qinwei Fan, Qian Kang, Lei Niu
June 29, 2021 (v1)
Keywords: extreme learning machine, firefly algorithm, flower pollination algorithm, Optimization
Extreme learning machine (ELM) has aroused a lot of concern and discussion for its fast training speed and good generalization performance, and it has been used diffusely in both regression and classification problems. However, on account of the randomness of input parameters, it requires more hidden nodes to obtain the desired accuracy. In this paper, we come up with a firefly-based adaptive flower pollination algorithm (FA-FPA) to optimize the input weights and thresholds of the ELM algorithm. Nonlinear function fitting, iris classification and personal credit rating experiments show that the ELM with FA-FPA (FA-FPA-ELM) can obtain significantly better generalization performance (such as root mean square error, classification accuracy) than traditional ELM, ELM with firefly algorithm (FA-ELM), ELM with flower pollination algorithm (FPA-ELM), ELM with genetic algorithm (GA-ELM) and ELM with particle swarm optimization (PSO-ELM) algorithms.
Martensitic Transformation, Thermal Analysis and Magnetocaloric Properties of Ni-Mn-Sn-Pd Alloys
Asma Wederni, Mihail Ipatov, Eloi Pineda, Lluisa Escoda, Julian-Maria González, Mohamed Khitouni, Joan-Josep Suñol
June 29, 2021 (v1)
Subject: Materials
Keywords: entropic change, Heusler alloys, magneto-structural transition, magnetocaloric effect, martensitic transition
Martensitic transition and magnetic response of Ni50−x Pdx,y Mn36 Sn14−y (x = 0, 1, 2 and y = 0, 1) Heusler alloys were analysed. The crystalline structure of each composition was solved by X-ray diffraction pattern fitting. For x = 1 and 2, the L21 austenite structure is formed and, for y = 1, the crystallographic phase is a modulated martensitic structure. From differential scanning calorimetry scans, we determine characteristic transformation temperatures and the entropy/enthalpy changes. The temperatures of the structural transformation increase with the addition of Pd to replace Ni or Sn, whereas the austenitic Curie temperature remains almost unvarying. In addition, the magneto-structural transition, investigated by magnetic measurements, is adjusted by suitable Pd doping in the alloys. The peak value of the magnetic entropy changes reached 4.5 J/(kg K) for Ni50Mn36Sn13Pd1 (external field: 50 kOe).
Optimal Sizing of an Island Hybrid Microgrid Based on Improved Multi-Objective Grey Wolf Optimizer
Wenqiang Zhu, Jiang Guo, Guo Zhao, Bing Zeng
June 29, 2021 (v1)
Keywords: energy management, grey wolf optimizer, hybrid energy system, island microgrid, sizing optimization, tidal current energy
The hybrid renewable energy system is a promising and significant technology for clean and sustainable island power supply. Among the abundant ocean energy sources, tidal current energy appears to be very valuable due to its excellent predictability and stability, particularly compared with the intermittent wind and solar energy. In this paper, an island hybrid energy microgrid composed of photovoltaic, wind, tidal current, battery and diesel is constructed according to the actual energy sources. A sizing optimization method based on improved multi-objective grey wolf optimizer (IMOGWO) is presented to optimize the hybrid energy system. The proposed method is applied to determine the optimal system size, which is a multi-objective problem including the minimization of annualized cost of system (CACS) and deficiency of power supply probability (DPSP). MATLAB software is utilized to program and simulate the hybrid energy system. Optimization results confirm that IMOGWO is feasible to opt... [more]
5-Fluorouracil Loaded Biogenic and Albumin Capped Gold Nanoparticles Using Bacterial Enzyme—In Vitro-In Silico Gastroplus® Simulation and Prediction
Wael A. Mahdi, Afzal Hussain, Mohd. Ramzan
June 29, 2021 (v1)
Subject: Biosystems
Keywords: 5-fluorouracil, albumin capping, biogenic gold nanoparticles, hemocompatible, in silico GastroPlus® simulation and prediction, MCF-7 cell lines
The study investigated in situ biosynthesis of albumin capped 5-fluorouracil (5-FU) loaded gold nanoparticles (NPs) using bacterial extract for enhanced efficacy against MCF-7 and in silico prediction using a GastroPlus® software. The optimized formulations were characterized for morphology, size, zeta potential, drug loading (%DL) and entrapment (), compatibility, in vitro drug release, in vitro hemolysis, cellular toxicity and apoptosis studies. The results exhibited highly dispersed albumin capped mono-metallic stable NPs. Spherical size, negative zeta potential and polydispersity index were in range of 38.25−249.62 nm, 18.18−29.87 mV and 0.11−0.283, respectively. F11, F7 and F3 showed a progressive increase in %DL and with increased concentration of the cellular lysate (100% > 50% > 10%). The drug release was relatively extended over 48 h as compared to drug solution (96.64% release within 5 h). The hemolysis result ensured hemocompatibility (<14%) at the explored concentration.... [more]
Volatile Fatty Acids and Biomethane Recovery from Thickened Waste Activated Sludge: Hydrothermal Pretreatment’s Retention Time Impact
Farokh laqa Kakar, Ahmed El Sayed, Neha Purohit, Elsayed Elbeshbishy
June 29, 2021 (v1)
Keywords: anaerobic digestion, biomethane, hydrothermal pretreatment, thickened waste activated sludge, volatile fatty acids
The main objective of this study was to evaluate the hydrothermal pretreatment’s retention time influence on the volatile fatty acids and biomethane production from thickened waste activated sludge under mesophilic conditions. Six different retention times of 10, 20, 30, 40, 50, and 60 min were investigated while the hydrothermal pretreatment temperature was kept at 170 °C. The results showed that the chemical oxygen demand (COD) solubilization increased by increasing the hydrothermal pretreatment retention time up to 30 min and stabilized afterwards. The highest COD solubilization of 48% was observed for the sample pretreated at 170 °C for 30 min. Similarly, the sample pretreated at 170 °C for 30 min demonstrated the highest volatile fatty acids yield of 14.5 g COD/Lsubstrate added and a methane yield of 225 mL CH4/g TCODadded compared to 4.3 g COD/Lsubstrate added and 163 mL CH4/g TCODadded for the raw sample, respectively. The outcome of this study revealed that the optimum conditio... [more]
Whispering-Gallery-Mode for Coherent Random Lasing in a Dye-Doped Polystyrene Encapsulated Silica-Glass Capillary
Kai Nie, Yueqi Wang, Zhenzhen Zhang, Gang Zou, Xiaolong Xu, Zhijia Hu, Qijin Zhang
June 29, 2021 (v1)
Subject: Other
Keywords: coherent random lasing (RL), random lasers, whispering gallery modes
Dye-doped polystyrene (DDPS) encapsulated in a silica-glass capillary with a diameter of 300 μm was fabricated through radical polymerization of styrene within the capillary. The coherent random lasing (RL) with full width at half maximum (FWHM) of 0.36 nm and a quality factor of 1608 was produced in the DDPS with the capillary when pumping at 532 nm. However, the incoherent RL with FWHM of 6.62 nm and a quality factor of 92 was produced in the DDPS without the capillary. A detailed investigation on this phenomenon by changing the diameter of the capillary and core refractive index (RI) reveals that there exists a strong whispering gallery mode (WGM) resonance in the capillary, which helps generate the coherent RL. The findings may open up a new approach for the fabrication of highly efficient photonic devices.
Development and Testing of a Block Hydrocyclone
Alexandr Repko, Milan Sága, Boris Sentyakov, Vladislav Sviatskii
June 29, 2021 (v1)
Keywords: block hydrocyclone, filter, filtration unit, flow hydrodynamics, screw swirler, swirl unit
The study aimed to theoretically substantiate the efficiency of liquid purification and obtain corroborating experimental data for a hydrocyclone, consisting of several blocks. Mathematical models of the process of hydrodynamic fluid filtration were developed with the use of screw swirlers. The obtained mathematical models characterize all the main processes of fluid movement in various zones of the functioning of the hydrocyclone. Formulas for calculating the structures of hydrocyclone blocks are included. A block for swirling the flow of the liquid to be cleaned has been made in the form of a three-way screw. For the first time, wear-resistant and high-strength plastic ZEDEX ZX-324 has been used as a material. An experimental study was conducted and the change in the Reynolds number and the coefficient of fluid consumption was shown, using different constructions of the three-way screw. The research results confirmed the correctness and sufficiency of mathematical models for the deve... [more]
Samnamul (Shoots of Aruncus dioicus) Inhibit Adipogenesis by Downregulating Adipocyte-Specific Transcription Factors in 3T3-L1 Adipocytes
Ji Yeon Lee, Jeong-Yong Park, Hyun Taek Seo, Hyun-A Seong, Yun-Jeong Ji, Seung Eun Lee, Kyung Hye Seo, Hyung Don Kim
June 29, 2021 (v1)
Subject: Biosystems
Keywords: adipocytes, adipogenesis, Aruncus dioicus, lipogenesis, phenolics
Adipocyte-specific transcription factors and antioxidants are considered the best target of obesity. Aruncus dioicus var. kamtschaticus (A. dioicus, Samnamul) is easily available owing to edible and inexpensive. However, the anti-adipogenic effects of the underlying mechanism of A. dioicus extract (ADE) have not yet been reported. In the present study, we evaluate anti-adipogenic pathway in 3T3-L1 adipocytes, antioxidant activities and quantified phenolics using high-performance liquid chromatography of ADE. The results revealed ADE had reduced adipocyte differentiation (0.72-fold vs. MDI (media of differentiation) control), triglyceride (TG; 0.50-fold vs. MDI control, p < 0.001), and total cholesterol contents (0.77-fold vs. MDI control) by regulating adipocyte-specific transcription factors (C/EBPα, PPARγ, and SREBP1) and their downstream mRNA (AdipoQ, Ap2, SREBP1-c, and FAS) levels. Furthermore, ADE has higher total phenol and flavonoid contents and scavenging assay in the DPPH a... [more]
The Combination of Simultaneous Plasma Treatment with Mg Nanoparticles Deposition Technique for Better Mung Bean Seeds Germination
Sarunas Varnagiris, Simona Vilimaite, Ieva Mikelionyte, Marius Urbonavicius, Simona Tuckute, Darius Milcius
June 29, 2021 (v1)
Keywords: germination, Mg deposition, non-thermal plasma, plasma treatment, surface modification
A novel method based on the combination of simultaneous cold plasma treatment with Mg nanoparticles deposition, applied to Mung bean seeds by improving their quality, is presented. The SRIM simulation reveals that only the very top layer of the seeds surface can be altered by the plasma. The experimental analysis indicates surface composition changes with a polar groups formation. These groups initiate the shift of surface characteristics from hydrophobic to hydrophilic. The chemical bond analysis shows the formation of MgO and Mg(OH)2 compounds, which acts as a positive factor for seeds germination and growth. The germination experiments showed a 70% outcome with an average of 73.9 mm sprouts length after 30 min of plasma treatment compared to the initial seeds (40% outcome and 71.3 mm sprouts length).
Responsible Design for Sustainable Innovation: Towards an Extended Design Process
Ricardo J. Hernandez, Julian Goñi
June 29, 2021 (v1)
Keywords: design process, innovation, responsible design, sustainable design, sustainable innovation
Design as a discipline has changed a lot during the last 50 years. The boundaries have been expanded partially to address the complexity of the problems we are facing nowadays. Areas like sustainable design, inclusive design, codesign, and social design among many more have emerged in response to the failures of the production and consumption system in place. In this context, social, environmental, and cultural trends have affected the way artefacts are designed, but the design process itself remains almost unchanged. In some sense, more criteria beyond economic concerns are now taken into consideration when social and environmental objectives are pursued in the design process, but the process to reach those objectives responds to the same stages and logic as in traditional approaches motivated only by economic aims. We propose in this paper an alternative way to understand and represent the design process, especially oriented to develop innovations that are aligned with the social, en... [more]
Water-Soluble Carbon Quantum Dots Modified by Amino Groups for Polarization Fluorescence Detection of Copper (II) Ion in Aqueous Media
Anastasia Yakusheva, Dmitry S. Muratov, Dmitry Arkhipov, Gopalu Karunakaran, Sergei A. Eremin, Denis Kuznetsov
June 29, 2021 (v1)
Subject: Other
Keywords: carbon quantum dots, copper cation, fluorescence properties, polarization fluorescent analysis, water samples
Industrialization is serious for changing the environment and natural water composition, especially near cities and manufacturing areas. Logically, the new ultrasensitive technology for precise control of the quality and quantity of water sources is needed. Herein, an innovative method of polarization fluorescence analysis (FPA) was developed to measure the concentration of heavy metals in water. The approach was successfully applied for precise tests with reduced analysis time and increased measurement efficiency among laboratory methods. Based on this work, the investigations established the new type of carbon quantum dots (CQDs) with controllable fluorescence properties and functionalized amino—groups, which is appropriate for FPA. The parameters of one and two-step microwave synthesis routes are adjusted wavelength and fluorescence intensity of CQDs. Finally, under optimized conditions, the FPA is showed the detection of copper (2+) cations in water samples below European Union sta... [more]
Gas Turbine Intercoolers: Introducing Nanofluids—A Mini-Review
Ali Alsayegh, Naser Ali
June 29, 2021 (v1)
Subject: Materials
Keywords: heat exchanger, stability, suspension, thermophysical properties, working fluid
Coolant is one of the main factors affecting the overall thermal performance of the intercooler for the gas turbine intercooled cycle. The thermal conductivity of conventional coolants, such as water, is relatively low when compared to solid conducting materials, and therefore can hinder the progress towards achieving a compact and highly effective intercooler. Nanofluids are advanced types of working fluids that contain dispersed nanoparticles in conventional basefluids, and as such possess superior thermal conductivity compared to their counterparts. In this paper, a short review on the effect of different nanofluids on the thermal performance of gas turbines intercoolers is presented for the first time. Firstly, this work reviews the different designs of intercoolers used in gas turbines intercooled cycles. Then, it explains the different types of nanofluids and their fabrication processes. The effective parameters, such as physical stability, thermal conductivity, and viscosity are... [more]
Fermentation of Organic Residues to Beneficial Chemicals: A Review of Medium-Chain Fatty Acid Production
Panagiota Stamatopoulou, Juliet Malkowski, Leandro Conrado, Kennedy Brown, Matthew Scarborough
June 29, 2021 (v1)
Keywords: carboxylate platform, carboxylic acids, chain elongation, medium-chain fatty acids, mixed culture fermentation
Medium-chain fatty acids (MCFAs) have a variety of uses in the production of industrial chemicals, food, and personal care products. These compounds are often produced through palm refining, but recent work has demonstrated that MCFAs can also be produced through the fermentation of complex organic substrates, including organic waste streams. While “chain elongation” offers a renewable platform for producing MCFAs, there are several limitations that need to be addressed before full-scale implementation becomes widespread. Here, we review the history of work on MCFA production by both pure and mixed cultures of fermenting organisms, and the unique metabolic features that lead to MCFA production. We also offer approaches to address the remaining challenges and increase MCFA production from renewable feedstocks.
Design of a Separation Process for Natural 2-Phenylethanol with Economic and Safety Considerations
Luis E. Puga-Córdova, Zahira A. Pérez-Sánchez, Antíoco López-Molina, Laura Conde-Báez, Arturo Jiménez-Gutiérrez, Carolina Conde-Mejía
June 29, 2021 (v1)
Keywords: bioprocess stream index, natural 2-phenylethanol, safety assessment, separation process design, whey fermentation
The present work aimed to design a separation process for 2-phenylethanol (2-PEA) produced by whey fermentation and to evaluate its economic potential. The separation sequence consisted of a liquid−liquid extraction column followed by two distillation columns for 2-PEA purification and solvent recovery. In addition, the use of ethyl acetate as a solvent for the extraction process was analyzed. The results, aided by the Aspen Plus v.10 process simulator, showed that 2-PEA can be separated with a purity of 96% by weight. The operating cost of the process, estimated at USD 22.70 per kilogram, shows that the separation alternative developed in this work has a high economic potential. The use of ethyl acetate as a solvent was found to efficiently remove 2-PEA from the fermentation mixture. From a process safety analysis point of view, the use of a bioprocess safety index developed in this work identified the separation process sections that could require special attention as part of the saf... [more]
Improving Ammonium Sorption of Bayah Natural Zeolites by Hydrothermal Method
Teguh Kurniawan, Saiful Bahri, Anita Diyanah, Natasya D. Milenia, Nuryoto Nuryoto, Kajornsak Faungnawakij, Sutarat Thongratkaew, Muhammad Roil Bilad, Nurul Huda
June 29, 2021 (v1)
Subject: Materials
Keywords: Adsorption, clinoptilolite, crystallinity, Freundlich, intraparticle, ion-exchange, isotherm, kinetic, mordenite, surface area
Natural zeolites are easily found and abundant in Indonesia. The natural zeolites are low-cost minerals; however, their ammonium sorption is poor. A hydrothermal method was applied to improve the ammonium sorption. Hydrothermal treatment times were varied 8, 24, and 32 h. The parent and hydrothermal treated samples were characterized by using X-ray diffraction (XRD), Field Emission Scanning Electron Microscopes (FE-SEM), Fourier-transform infrared spectroscopy (FTIR), and nitrogen physisorption. Ammonium adsorption was performed using a batch reactor to evaluate the adsorption performance of the prepared zeolite samples. The 8 h hydrothermal (HT 8 h) treated zeolites showed the highest ammonium removal percentage among others. The XRD analysis of HT 8 h shows a higher crystallinity of mordenite and the Brunauer−Emmett−Teller (BET) model shows a surface area of 105 m2/g, much larger as compared to the parent with a surface area of 19 m2/g. Various kinetic and isotherms models were also... [more]
Quality of Watermelon Juice Concentrated by Forward Osmosis and Conventional Processes
Rebecca R. Milczarek, Carl W. Olsen, Ivana Sedej
June 29, 2021 (v1)
Keywords: concentrate, forward osmosis, juice, watermelon (Citrullus lanatus)
Watermelon (Citrullus lanatus) juice is known for its refreshing flavor, but its high perishability limits its availability throughout the year. Watermelon juice concentrate has extended shelf-life and lower transportation and storage costs, but the conventional thermal evaporation process for concentrating juice degrades the nutritional components and sensory quality of the product. Thus, in this work, a large-scale, non-thermal forward osmosis (FO) process was used to concentrate fresh watermelon juice up to 65°Brix. The FO concentrate was compared to thermal concentrate and fresh juices, and to commercially available refrigerated watermelon juices, in terms of lycopene and citrulline content, total soluble phenolics, antioxidant activity, and sensory properties. The FO concentrate had statistically similar (p < 0.05) levels of all the nutrients of interest except antioxidant activity, when compared to the thermal concentrate. The reconstituted FO concentrate maintained the same a... [more]
Syngas Derived from Lignocellulosic Biomass Gasification as an Alternative Resource for Innovative Bioprocesses
Cosetta Ciliberti, Antonino Biundo, Roberto Albergo, Gennaro Agrimi, Giacobbe Braccio, Isabella de Bari, Isabella Pisano
June 21, 2021 (v1)
Keywords: biorefinery, gasification, lignocellulosic biomass, syngas fermentation, Wood–Ljungdahl pathway
A hybrid system based on lignocellulosic biomass gasification and syngas fermentation represents a second-generation biorefinery approach that is currently in the development phase. Lignocellulosic biomass can be gasified to produce syngas, which is a gas mixture consisting mainly of H2, CO, and CO2. The major challenge of biomass gasification is the syngas’s final quality. Consequently, the development of effective syngas clean-up technologies has gained increased interest in recent years. Furthermore, the bioconversion of syngas components has been intensively studied using acetogenic bacteria and their Wood−Ljungdahl pathway to produce, among others, acetate, ethanol, butyrate, butanol, caproate, hexanol, 2,3-butanediol, and lactate. Nowadays, syngas fermentation appears to be a promising alternative for producing commodity chemicals in comparison to fossil-based processes. Research studies on syngas fermentation have been focused on process design and optimization, investigating th... [more]
Antioxidant Molecules from Plant Waste: Extraction Techniques and Biological Properties
Cynthia E. Lizárraga-Velázquez, Nayely Leyva-López, Crisantema Hernández, Erick Paul Gutiérrez-Grijalva, Jesús A. Salazar-Leyva, Idalia Osuna-Ruíz, Emmanuel Martínez-Montaño, Javier Arrizon, Abraham Guerrero, Asahel Benitez-Hernández, Anaguiven Ávalos-Soriano
June 21, 2021 (v1)
Keywords: bioactive peptides, Extraction, fruit, green technologies, phenolic compounds, phytosterols, residues, terpenes, valorization, vegetable
The fruit, vegetable, legume, and cereal industries generate many wastes, representing an environmental pollution problem. However, these wastes are a rich source of antioxidant molecules such as terpenes, phenolic compounds, phytosterols, and bioactive peptides with potential applications mainly in the food and pharmaceutical industries, and they exhibit multiple biological properties including antidiabetic, anti-obesity, antihypertensive, anticancer, and antibacterial properties. The aforementioned has increased studies on the recovery of antioxidant compounds using green technologies to value plant waste, since they represent more efficient and sustainable processes. In this review, the main antioxidant molecules from plants are briefly described and the advantages and disadvantages of the use of conventional and green extraction technologies used for the recovery and optimization of the yield of antioxidant naturals are detailed; finally, recent studies on biological properties of... [more]
A Genetic Programming Strategy to Induce Logical Rules for Clinical Data Analysis
José A. Castellanos-Garzón, Yeray Mezquita Martín, José Luis Jaimes Sánchez, Santiago Manuel López García, Ernesto Costa
June 21, 2021 (v1)
Keywords: clinical data, data mining, evolutionary computation, feature selection, genetic programming, Machine Learning
This paper proposes a machine learning approach dealing with genetic programming to build classifiers through logical rule induction. In this context, we define and test a set of mutation operators across from different clinical datasets to improve the performance of the proposal for each dataset. The use of genetic programming for rule induction has generated interesting results in machine learning problems. Hence, genetic programming represents a flexible and powerful evolutionary technique for automatic generation of classifiers. Since logical rules disclose knowledge from the analyzed data, we use such knowledge to interpret the results and filter the most important features from clinical data as a process of knowledge discovery. The ultimate goal of this proposal is to provide the experts in the data domain with prior knowledge (as a guide) about the structure of the data and the rules found for each class, especially to track dichotomies and inequality. The results reached by our... [more]
Stability Analysis of Delayed Tumor-Antigen-ActivatedImmune Response in Combined BCG and IL-2Immunotherapy of Bladder Cancer
Svetlana Bunimovich-Mendrazitsky, Leonid Shaikhet
June 21, 2021 (v1)
Subject: Biosystems
Keywords: cancer modeling, combined treatment model, discrete time delay, linear matrix inequalities (LMIs), Lyapunov functionals, stability conditions
We use a system biology approach to translate the interaction of Bacillus Calmette-Gurin (BCG) + interleukin 2 (IL-2) for the treatment of bladder cancer into a mathematical model. The main goal of this research is to predict the outcome of BCG + IL-2 treatment combinations. We examined whether the delay effect caused by the proliferation of tumor antigen-specific effector cells after the immune system destroys BCG-infected urothelium cells after BCG and IL-2 immunotherapy influences success in bladder cancer treatment. To do this, we introduce a system of differential equations where the variables are the main participants in the immune response after BCG installations to fight cancer: the number of tumor cells, BCG cells, immune cells, and cytokines involved in the tumor-immune response. The relevant parameters describing the dynamics of the system are taken from a variety of biological, clinical literature and estimated using the mathematical models. We examine the local stability a... [more]
The Effect of Deinking Process on Bioethanol Production from Waste Banknote Paper
Omid Yazdani Aghmashhadi, Ghasem Asadpour, Esmaeil Rasooly Garmaroody, Majid Zabihzadeh, Lisandra Rocha-Meneses, Timo Kikas
June 21, 2021 (v1)
Keywords: biorefinery, enzymatic hydrolysis, Fermentation, lignocellulose, pretreatment, zero-waste
The aim of this paper is to study the effect of reinking and pretreatment of waste banknote paper on its usability in the bioethanol production process. To this end, the tensile strength of worn banknote paper was first studied at different pH values. The sample with the lowest tensile strength was considered for the next sections. In the deinking process, NaOH at different concentrations (1%, 2%, 3%, and 4%) and in combination with ultrasonic treatment was applied. After deinking the pulp, two acidic and alkaline chemical pretreatments with concentrations of 1%, 2%, 3%, and 4% were used independently and in combination with ultrasonic. Enzymatic hydrolysis, following fermentation with Scheffersomyces stipitis, and crystallinity measurements were used to confirm the efficiency of the pretreatments. RSM Design Expert software was used to determine the optimal values by considering the three variables—enzyme loading, ultrasonic loading, and contact time for waste paper deinked (WPD) and... [more]
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