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Records with Subject: Biosystems
Showing records 296 to 320 of 1206. [First] Page: 1 9 10 11 12 13 14 15 16 17 Last
Cardoon Hydrolysate Detoxification by Activated Carbon or Membranes System for Bioethanol Production
Ana P. M. Tavares, Matthew J. A. Gonçalves, Teresa Brás, Gaetano R. Pesce, Ana M. R. B. Xavier, Maria C. Fernandes
March 1, 2023 (v1)
Subject: Biosystems
Keywords: activated carbon adsorption, bioethanol, cardoon hemicellulosic hydrolysate detoxification, membrane nanofiltration, microbial fermentation, modified Escherichia coli, Scheffersomyces stipites
Advanced biofuels incorporation into the transportation sector, particularly cellulosic bioethanol, is crucial for attaining carbon neutrality by 2050, contributing to climate changes mitigation and wastes minimization. The world needs biofuel to be commercially available to tackle the socioeconomic challenges coming from the continued use of fossil fuels. Cynara cardunculus (cardoon) is a cheap lignocellulosic raw biomass that easily grows in Mediterraneous soils and is a potential renewable resource for a biorefinery. This work aimed to study the bioethanol production from cardoon hemicellulosic hydrolysates, which originated from dilute sulfuric acid hydrolysis pretreatment. A detoxification step to remove released microbial fermentative inhibitors was evaluated by using both activated carbon adsorption and a nanofiltration membrane system. The Scheffersomyces stipitis CBS5773 yeast and the modified Escherichia coli MS04 fermentation performances at different experimental conditions... [more]
Fundamental Investigation on a Foam-Generating Microorganism and Its Potential for Mobility Reduction in High-Permeability Flow Channels
Miu Ito, Yuichi Sugai
March 1, 2023 (v1)
Subject: Biosystems
Keywords: bacterial cell number, enhanced oil recovery, ferrous sulfate, flooding experiment, foam, nanobubbles, permeability, protein, Pseudomonas aeruginosa, sand pack core
This study proposed a novel foam EOR technique using Pseudomonas aeruginosa to generate the foam and investigated the potential of the microbial foam EOR to modify the permeability of a high-permeability porous system. We investigated oxygen nanobubble, carbon dioxide nanobubble and ferrous sulfate concentrations to discover the optimal levels for activating the foam generation of the microorganism through cultivation experiments. We also clarified the behavior of the microbial foam generation and the bioproducts that contribute to the foam generation. The potential of the foam to decrease the permeability of high-permeability porous systems was evaluated through flooding experiments using sand pack cores. The foam generation became more active with the increase in the number of nanobubbles, while there was an optimal concentration of ferrous sulfate for foam generation. The foam was identified as being induced by the proteins produced by the microorganism, which can be expected to bri... [more]
Experimental Study of Power Generation and COD Removal Efficiency by Air Cathode Microbial Fuel Cell Using Shewanella baltica 20
Subhashis Das, Rajnish Kaur Calay
February 28, 2023 (v1)
Subject: Biosystems
Keywords: COD removal efficiency, energy harvest, microbial fuel cell, power density, Shewanella baltica 20
Microbial fuel cells (MFCs) are a kind of bioreactor for generating electricity, facilitated by exoelectrogens while treating wastewater. The present article focuses on the performance of an air cathode plexiglass MFC in terms of chemical oxygen demand (COD) removal efficiency and power output by performing two sets of experiments. The proton exchange membrane and electrode materials were Nafion 117 and carbon felts, whereas, for stable biofilm formation on the anode surface, a pure culture of Shewanella baltica 20 was used. Firstly, sterile Luria-Bertani (LB) media containing lactate, ranging from 20 to 100 mM, was continuously fed to an MFC, and a maximum power density of 55 mW/m2 was observed. Similarly, artificial wastewater with COD ranging from 3250 mg/L to 10,272 mg/L was supplied to the MFC in the second set of experiments. In this case, the maximum power density and COD removal efficiency were 12 mW/m2 and 57%, respectively. In both cases, the hydraulic retention time (HRT) wa... [more]
Optimization Study on Microwave-Assisted Hydrothermal Liquefaction of Malaysian Macroalgae Chaetomorpha sp. for Phenolic-Rich Bio-Oil Production
Mei Yin Ong, Saifuddin Nomanbhay
February 28, 2023 (v1)
Subject: Biosystems
Keywords: bio-oil, Chaetomorpha sp., Folin–Ciocalteu method, microwave-assisted hydrothermal liquefaction, phenolic determination, RSM
There are several methods of biomass conversion, including hydrothermal liquefaction (HTL). The implementation of microwave technology in the HTL process is still new, especially on the conversion of marine biomass into bio-crude. In this work, the macroalgae Chaetomorpha sp. was used as the biomass feedstock to produce phenolic-rich bio-oil through microwave-assisted HTL. Chaetomorpha sp. was abundantly found in Malaysia, creating a green tides issue. By utilizing these algae, the green tide issue can be solved and value-added bio-oil is obtained. However, bio-oil from macroalgae has a relatively low heating value, restricting its fuel application. Therefore, it is suggested to be used for bio-polymer synthesis, including bio-based phenol formaldehyde. In this study, the effect of different parameters, such as reaction temperature, preloaded pressure, water-to-algal biomass ratio, and holding time, on both the bio-oil yield and phenolic yield was evaluated. Folin−Ciocalteu method was... [more]
Mechanism of Electron Acceptor Promoting Propionic Acid Transformation in Anaerobic Fermentation
Hongjing Jing, Wenzhe Li, Ming Wang, Hao Jiao, Yong Sun
February 28, 2023 (v1)
Subject: Biosystems
Keywords: anaerobic fermentation, electron acceptor, function gene, microbial flora, propionic acid conversion
To improve the conversion efficiency of propionic acid in the post-anaerobic fermentation of biogas slurry, the anaerobic fermentation process using biogas slurry with a high acid content was simulated in an anaerobic reactor at 35 ± 0.5 °C using sodium propionate as the sole substrate. The effects of different electron acceptors (NO3−, SO42− and Fe3+) on propionic acid conversion and the succession of microbial community structures were investigated. The results showed that the experimental group with the electron acceptor NO3− exhibited the best anaerobic fermentation effect, with a maximum propionate removal rate of 94%, which was 36% higher than the control group without an electron acceptor. The maximum methane production rate was 307.6 mL/g COD, an increase of 30% compared with the control group. Thauera, Aquabacterium, Desulfomicrobium, Clostridium_sensu_stricto_1, and other functional microorganisms were all enriched. The dominant functional genes related to redox reactions, su... [more]
Accelerating Microbial Activity of Soil Aquifer Treatment by Hydrogen Peroxide
Liron Friedman, Kartik Chandran, Dror Avisar, Edris Taher, Amanda Kirchmaier-Hurpia, Hadas Mamane
February 28, 2023 (v1)
Subject: Biosystems
Keywords: anoxic, denitrification, hydrogen peroxide, nitrification, soil aquifer treatment
Soil aquifer treatment (SAT), as a gravity-based wastewater reuse process, is limited by oxygen availability to the microbial community in the soil. Using oxygen from enzymatic degradation of H2O2 to generate hyper-oxygen conditions can exceed solubility limitations associated with aeration, but little is known about the effect of hyper-oxygen conditions on the microbial community and the dominant bio-reactions. This study examined the impact of H2O2 addition on the community structure and process performance, along with SAT depth. Overall, two soil columns were incrementally fed synthetic secondary effluents to simulate infiltration through SAT. The experimental column received 14 mg/L hydrogen peroxide to double the level of natural oxygen available. The microbial kinetics of nitrifiers and heterotrophs were evaluated. We found that all of the H2O2 was degraded within the top 10 cm of the column, accompanied by a higher removal of COD (23 ± 0.25%) and ammonia (31 ± 3%) in comparison... [more]
Controlling the Hydro-Swelling of Smectite Clay Minerals by Fe(III) Reducing Bacteria for Enhanced Oil Recovery from Low-Permeability Reservoirs
Kai Cui, Chengjun Wang, Li Li, Jungang Zou, Weihong Huang, Zhongzhi Zhang, Heming Wang, Kun Guo
February 28, 2023 (v1)
Subject: Biosystems
Keywords: enhanced oil recovery, Fe(III) reducing microorganisms, inhibiting/shrinking hydro-swelling, low-permeability oil reservoirs, smectite clay minerals
The hydro-swelling of smectite clay minerals in low-permeability reservoirs further decreases the reservoir permeability and results in low oil recovery. Currently, the traditional chemical anti-swelling agents are widely used, but most of them are only effective in the short term and are not environmentally friendly. Here, we report the use of Fe(III) reducing microorganisms (FeRM) as a novel green anti-swelling agent to enhance oil recovery from low-permeability reservoirs. The results showed that FeRM (Proteus hauserifective) inhibited/reduced the hydro-swelling of smectite clay minerals through a three-step biochemical mineralization reaction process. The structural Fe(III) reduction in minerals by FeRM can be an important driving force for illitization. The maximum inhibition efficiency (36.6%) and shrinkage efficiency (69.3%) were achieved at 35 °C and 0.1 Mpa. Furthermore, core displacement tests showed that FeRM reduced the waterflooding injection pressure by 61.1%, increased t... [more]
Continuous Bioethanol Production by Fungi and Yeast Working in Tandem
Valeria Rahamim, Faina Nakonechny, Aharon Azagury, Marina Nisnevitch
February 28, 2023 (v1)
Subject: Biosystems
Keywords: bioethanol, P. stipitis, S. cerevisiae, small bioreactor platform capsules, T. reesei
Biofuel is considered one of the most viable alternatives to fossil fuels derived from the dwindling petroleum resources that damage the environment. Bioethanol could be manufactured from agricultural wastes, thus providing inexpensive natural resources. Several strategies have been utilized to convert lignocellulosic hydrolysate to bioethanol with various suspended microorganisms. In this study, we alternatively propose to encapsulate these microorganisms in bioreactor setups. An immobilized cell system can provide resistance to the inhibitors present in hydrolysates, enhance productivity, facilitate the separation process, and improve microorganism recycling. Herein, we developed a continuous bioethanol production process by encapsulating three types of micro-organisms: T. reesei, S. cerevisiae, and P. stipitis. These microorganisms were encapsulated in SBP (“Small Bioreactor Platform”) capsules and tested for their viability post encapsulation, biological activity, and bioethanol pr... [more]
Effect of a Plasma Burner on NOx Reduction and Catalyst Regeneration in a Marine SCR System
Jaehwan Jang, Seongyool Ahn, Sangkyung Na, Jinhee Koo, Heehwan Roh, Gyungmin Choi
February 28, 2023 (v1)
Subject: Biosystems
Keywords: catalyst, De-NOx, plasma burner, regeneration, selective catalytic reduction
The problem of environmental pollution by the combustion of fossil fuels in diesel engines, to which NOx emission is a dominant culprit, has accelerated global environmental pollution and global and local health problems such as lung disease, cancer, and acid rain. Among various De-NOx technologies, SCR (Selective Catalytic Reduction) systems are known to be the most effective technology for actively responding to environmental regulations set by the IMO (International Maritime Organization) in marine diesel applications. The ammonia mixes with the exhaust gas and reacts with the NOx molecules on the catalyst surface to form harmless N2 and H2O. However, since the denitrification efficiency of NOx can be rapidly changed depending on the operating temperature from 250 °C to 350 °C at 0.1% sur contents of the catalyst used in the SCR, a device capable of controlling the exhaust gas temperature is essential for the normal operation of the catalyst. In addition, when the catalyst is expose... [more]
The Consistency of Yields and Chemical Composition of HTL Bio-Oils from Lignins Produced by Different Preprocessing Technologies
Hilde Vik Halleraker, Konstantinos Kalogiannis, Angelos Lappas, Rafael C. A. Castro, Ines C. Roberto, Solange I. Mussatto, Tanja Barth
February 28, 2023 (v1)
Subject: Biosystems
Keywords: Biomass, hydrothermal liquefaction, lignin, lignin to liquid, solvolysis
This work evaluates the effect of feedstock type and composition on the conversion of lignin to liquid by solvolysis with formic acid as hydrogen donor (LtL), by analyzing the yields and molecular composition of the liquid products and interpreting them in terms of both the type and the preprocessing of the lignocellulosic biomass using chemometric data analysis. Lignin samples of different types and purities from softwood, hardwood, and grasses (rice straw and corn stover) have been converted to bio-oil, and the molecular composition analyzed and quantified using GC-MS. LtL solvolysis was found to be a robust method for lignin conversion in terms of converting all samples into bio-oils rich in phenolic compounds regardless of the purity of the lignin sample. The bio-oil yields ranged from 24−94 wt.% relative to lignin input and could be modelled well as a function of the elemental composition of the feedstock. On a molecular basis, the softwood-derived bio-oil contained the most guaia... [more]
Deep Transfer Learning Techniques-Based Automated Classification and Detection of Pulmonary Fibrosis from Chest CT Images
Asif Hassan Syed, Tabrej Khan, Sher Afzal Khan
February 27, 2023 (v1)
Subject: Biosystems
Keywords: chest computed tomography, classification and detection, pulmonary fibrosis, ResNet50v2, transfer learning techniques
Pulmonary Fibrosis (PF) is a non-curable chronic lung disease. Therefore, a quick and accurate PF diagnosis is imperative. In the present study, we aim to compare the performance of the six state-of-the-art Deep Transfer Learning techniques to classify patients accurately and perform abnormality localization in Computer Tomography (CT) scan images. A total of 2299 samples comprising normal and PF-positive CT images were preprocessed. The preprocessed images were split into training (75%), validation (15%), and test data (10%). These transfer learning models were trained and validated by optimizing the hyperparameters, such as the learning rate and the number of epochs. The optimized architectures have been evaluated with different performance metrics to demonstrate the consistency of the optimized model. At epoch 26, using an optimized learning rate of 0.0000625, the ResNet50v2 model achieved the highest training and validation accuracy (training = 99.92%, validation = 99.22%) and mini... [more]
Special Issue on “Biological Network Approaches and Applications”
Seong Beom Cho
February 27, 2023 (v1)
Subject: Biosystems
Biological phenomena comprise various interactions between genes and molecules [...]
Mannitol-Based Media and Static pH Are Efficient Conditions for Red Pigment Production from Monascus purpureus ATCC 36928 in Submerged Culture
Alan Gomes Lima, Luciana Arantes Dantas, Mariana Buranelo Egea
February 27, 2023 (v1)
Subject: Biosystems
Keywords: bioprocess condition, bioreactor, dye from bioprocess
Fungi of the Monascus species are used in Asia for the production of fermented foods, mainly due to the ability of these fungi to produce secondary metabolites such as pigments. Due to the growing discussion about the use of synthetic dyes and the fact that their ingestion is associated with harm to human health, studies have sought to replace these dyes using natural pigments, and new alternatives for the production of these natural pigments have been presented. In this context, Monascus pigments are a viable alternative for application in the food industry. This study aimed to evaluate different main carbon sources and pH conditions in the red pigment production of Monascus sp. We found that mannitol, when used as the only carbon source, stimulated the production of extracellular red pigment, reaching a concentration of 8.36 AU in 48 h, while glucose and sucrose reached concentrations of 1.08 and 1.34 AU, respectively. Cultivation in a bioreactor using mannitol showed great potential... [more]
Evaluation of the Effect of Deep Compost Application in the Areas around Vineyard Tree Trunks on Selected Soil Chemical Properties and the Vegetative Growth of the Vine
Patrik Burg, Barbora Badalíková, Vladimír Mašán, Štefan Csáki, Jana Burgová, Jan Turan, Arkadiusz Matwijczuk
February 27, 2023 (v1)
Subject: Biosystems
Keywords: annual shoots, compost, grapevine nutrition, soil fertility, vegetative growth, viticulture
In the context of sustainability, viticulture will address issues related to soil fertility in the coming period. Greater attention will therefore be paid to replacing traditional manure-based fertilisers, such as farmyard manure, with new types of fertiliser in the form of composts, digestate, etc. Experience to date suggests that good-quality composts are not only a source of nutrients that the vines take from the soil each year, but also a source of organic matter. The application of compost and its subsequent decomposition in the soil profile can have a positive effect on the growth of the roots and above-ground parts of the vine. However, optimising the effects and action of compost is linked to determining the necessary doses and methods of application. The aim of this three-year study was to provide an overview of the results aimed at evaluating the effects of the application of compost (CO) and compost enriched with the addition of lignohumate (CO+L20), at a rate of 30 t·ha−1,... [more]
In Vitro Evaluation of Commercial Probiotic Products Containing Streptococcus salivarius K12 by Assessment of Probiotic Viability and Inhibitory Potency against Respiratory Pathogens
Medana Zamfir, Iulia-Roxana Angelescu, Silvia-Simona Grosu-Tudor
February 27, 2023 (v1)
Subject: Biosystems
Keywords: antimicrobial activity, commercial probiotics, Streptococcus salivarius K12, upper respiratory infections, viability
Upper respiratory infections (URI) are the most frequent illnesses, especially in children. The majority of those infections are prescribed broad-spectrum antibiotics, which are associated with various side effects and with the increase in multi-drug-resistant strains. A promising alternative approach is the administration of the probiotic strain Streptococcus salivarius K12 (SSK12) that colonizes the upper respiratory tract (URT) and produces the salivaricins A2 and B, which strongly antagonize the growth of key respiratory pathogens. However, since for food supplements no quality controls of the active probiotic ingredient are mandatory, the efficacy of commercial products containing SSK12 may vary. This study aimed to investigate the in vitro efficacy of several commercial SSK12-containing probiotics, positioned for the prevention of respiratory infections. The parameters evaluated to determine the in vitro efficacy included the viability of the probiotic bacterial strain and the mi... [more]
The Prospects of Algae-Derived Vitamins and Their Precursors for Sustainable Cosmeceuticals
Neha Arora, George P. Philippidis
February 27, 2023 (v1)
Subject: Biosystems
Keywords: algae, bioactive compounds, skin treatment, vitamins
Aquatic algae are a rich source of a wide range of bioproducts intended to compete for a sizable global market share. Thanks to the gradual shift towards the use of natural products, microalgae-derived bioactive compounds offer an ecofriendly and vegan option to the cosmeceutical sector, whose products aim to improve skin health but currently consist of mostly synthetic chemicals. In particular, algae-derived vitamins and their precursors are being explored and widely used in the cosmeceuticals industry as compounds that contain biologically active ingredients with therapeutic benefits. The present review highlights the current strategies for industrial production of an array of vitamins from algae for cosmeceutical applications. When compared to traditional plant sources, algae have been found to accumulate vitamins, such as A, B1, B2, B6, B12, C and E, in high concentrations. The purpose of this review is to provide context for the development of a green and sustainable algae-derived... [more]
Proteomics Provide Insight into the Interaction between Selenite and the Microalgae Dunaliella salina
Xiaoyu Jiang, Liu Yang, Yinghui Wang, Fajun Jiang, Junxiang Lai, Kailin Pan
February 27, 2023 (v1)
Subject: Biosystems
Keywords: abiotic stress, Dunaliella salina, proteome, selenite
is currently one of the most commercially valuable microalgae species in the world. In reponse to selenite, D. salina is a microalgae with a high selenium content, thereby increasing its value, which is crucial for increasing its economic value as a nutrional supplement. However, the effects of selenite on D. salina are still unclear, and its molecular mechanism of the response to selenite stress is also elusive. Here, in order to study the effects of selenite on D. salina and the corresponding regulatory mechanism, we characterized the physiological phenotypes of D. salina under different selenite concentrations and carried out a quantitative proteomic study. The results showed that the effective concentration for 50% growth inhibition (EC50) of the algae was 192.7 mg/L after 11 days of cultivation. When selenite concentration was lower than 100 mg/L, selenite did not hinder the growth of D. salina in the early stage, but shortened the cell growth cycle, although cell growth was signi... [more]
Hybrid Filter and Genetic Algorithm-Based Feature Selection for Improving Cancer Classification in High-Dimensional Microarray Data
Waleed Ali, Faisal Saeed
February 27, 2023 (v1)
Subject: Biosystems
Keywords: cancer classification, filter feature selection, gene selection, Genetic Algorithm, microarray dataset
The advancements in intelligent systems have contributed tremendously to the fields of bioinformatics, health, and medicine. Intelligent classification and prediction techniques have been used in studying microarray datasets, which store information about the ways used to express the genes, to assist greatly in diagnosing chronic diseases, such as cancer in its earlier stage, which is important and challenging. However, the high-dimensionality and noisy nature of the microarray data lead to slow performance and low cancer classification accuracy while using machine learning techniques. In this paper, a hybrid filter-genetic feature selection approach has been proposed to solve the high-dimensional microarray datasets problem which ultimately enhances the performance of cancer classification precision. First, the filter feature selection methods including information gain, information gain ratio, and Chi-squared are applied in this study to select the most significant features of cancer... [more]
Anti-Inflammatory and Anti-Diabetic Activity of Ferruginan, a Natural Compound from Olea ferruginea
Abdur Rauf, Umer Rashid, Zafar Ali Shah, Gauhar Rehman, Kashif Bashir, Johar Jamil, Iftikhar, Abdur Rahman, Abdulrahman Alsahammari, Metab Alharbi, Abdulmajeed Al-Shahrani, Giovanni Ribaudo
February 27, 2023 (v1)
Subject: Biosystems
Keywords: anti-diabetic, anti-inflammatory, ferruginan, molecular docking, Olea ferruginea, Oleaceae
Inflammation is a complex response of the human organism and relates to the onset of various disorders including diabetes. The current research work aimed at investigating the anti-inflammatory and anti-diabetic effects of ferruginan, a compound isolated from Olea ferruginea. Its in vitro anti-inflammatory activity was determined by using the heat-induced hemolysis assay, while the anti-diabetic effect of the compound was studied by the yeast cell glucose uptake assay. Ferruginan exhibited a maximum of 71.82% inhibition of inflammation and also increased the uptake of glucose by yeast cells by up to 74.96% at the highest tested concentration (100 µM). Moreover, ferruginan inhibited α-amylase dose-dependently, by up to 75.45% at the same concentration. These results indicated that ferruginan possesses promising anti-inflammatory and anti-diabetic properties in vitro, even if at high concentrations. To provide preliminary hypotheses on the potentially multi-target mechanisms underlying s... [more]
Formation of Oxidative Compounds during Enzymatic Hydrolysis of Byproducts of the Seafood Industry
Mehdi Nikoo, Joe M. Regenstein, Ali Haghi Vayghan, Noman Walayat
February 27, 2023 (v1)
Subject: Biosystems
Keywords: enzymatic hydrolysis, fish processing byproducts, fish protein hydrolysates, oxidation, storage
There is a significant potential to increase the sustainability of the fishing and aquaculture industries through the maximization of the processing of byproducts. Enzymatic hydrolysis provides an opportunity to valorize downstream fish industry byproducts for the production of protein hydrolysates (FPH) as a source of bioactive peptides (BAP) with health benefits. Deteriorative oxidative reactions may occur during the enzymatic hydrolysis of byproducts, influencing the safety or bioactivities of the end product. Lipid oxidation, autolysis mediated by endogenous enzymes in viscera, protein degradation, and formation of low-molecular-weight metabolites are the main reactions that are expected to occur during hydrolysis and need to be controlled. These depend on the freshness, proper handling, and the type of byproducts used. Viscera, frames, trimmings, and heads are the byproducts most available for enzymatic hydrolysis. They differ in their composition, and, thus, require standardizati... [more]
The Interaction of Programmed Cell Death Protein and Its Ligands with Non-Coding RNAs in Neoplasms: Emerging Anticancer Immunotherapeutics
Mahmoud Kandeel, Duaa Althumairy, Ibrahim M. El-Sabagh, Saad Shousha, Yehia Hussin, Ahmed M. A. Meligy, Mohamed K. Zabady, Khaled M. Zahran, Nawal Elkhair, Abdulrahman Hereba, Mahmoud G. Elsebaei, Aliya Elamin, Faiza Irshad, Muhammad Sufyan, El-Awad M. El-Hassan, Ibrahim Albokhadaim
February 27, 2023 (v1)
Subject: Biosystems
Keywords: apoptosis, cancer, immunotherapy, ligand, noncoding RNA
Recent studies have demonstrated that cancer cells can elude immune cells by creating a sanctuary within the tumor’s microenvironment. Large amounts of immune-suppressing signaling proteins can be expressed by cancer cells. One of the most important mechanisms in this system is immune suppression caused by tumors and the modulation of the immune checkpoint. The immune checkpoint is modulated by both the programmed cell death protein 1 (PD-1) and its ligands, programmed death ligand 1 (PD-L1) and PD-L2. Non-coding RNAs (ncRNA), including the more well-known microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs), all play roles in the regulation of biological processes and extensive diseases such as cancer. Thus, the focus of this study is on the interactions between the programmed death protein and its ligands with miRNAs, lncRNAs, and circRNAs during tumorigenesis and tumor progression. Furthermore, some FDA-approved drugs for the treatment of various cancers... [more]
Grid-Connected Microbial Fuel Cell Modeling and Control in Distributed Generation
Fangmei Jiang, Liping Fan, Weimin Zhang, Naitao Yang
February 27, 2023 (v1)
Subject: Biosystems
Keywords: Boost converter, constant power control, double loop control structure, inverter, microbial fuel cells
Water shortages and water pollution have seriously threatened the sustainable development of the community. The grid-connected microbial fuel cell is an effective way to control the cost of wastewater treatment plants. Moreover, it solves the problem of low efficiency and high energy consumption. In view of the characteristics of strong coupling, non-linearity, and internal load in the process of microbial fuel cell grid connection, it is necessary to design the grid-connected unit of power electronic device. Based on the establishment of the microbial fuel cell stack model, the stability control and the constant power control scheme were designed for the chopper and inverter, respectively. The simulation results showed that the control strategy with the combination of voltage stabilizer and constant power can make a grid-connected system of all phase voltage and frequency output. The three-phase voltage Uabc was steady at 7 h and the voltage amplitude was controlled at roughly 380 V,... [more]
Sediment Carbon Sequestration and Driving Factors in Seagrass Beds from Hainan Island and the Xisha Islands
Qiuying Han, Chongyu Qiu, Wenxuan Zeng, Shiquan Chen, Muqiu Zhao, Yunfeng Shi, Xiaoli Zhang
February 27, 2023 (v1)
Subject: Biosystems
Keywords: eutrophic, microbes, oligotrophic, seagrass bed, sediment carbon stocks
Seagrass beds are considered to be substantial sinks of “blue carbon”. However, differentiation in the carbon sink capacities of seagrass beds in different regions with distinct nutrient conditions remains unclear. In this study, sediment carbon stocks, seagrass biomass, and microbial community structures and potential functions of seagrass beds in eutrophic seawater adjacent to Hainan Island and oligotrophic seawater around the Xisha Islands were compared. Our results showed that sediment mineralizable organic carbon and dry bulk density were substantially higher on Hainan Island than on the Xisha Islands (t-test, p < 0.05), while sediment carbon stocks and the total organic carbon were comparable between the two regions (p > 0.05). Similarly, seagrass biomass was much higher on Hainan Island (p < 0.05). Sediment carbon stocks positively correlated with sediment nitrogen and negatively correlated to sediment pH and grain size (p < 0.05). Bacterial diversities were similar in the... [more]
Correction: Xu et al. Preparation of Long-Term Antibacterial SiO2-Cinnamaldehyde Microcapsule via Sol−Gel Approach as a Functional Additive for PBAT Film. Processes 2020, 8, 897
Yangfan Xu, Chongxing Huang, Xiujie Dang, Muhammad Rafiullah Khan, Haohe Huang, Yuan Zhao, Shuangfei Wang
February 27, 2023 (v1)
Subject: Biosystems
In the original publication [...]
Can Celecoxib Assay in Preclinical Studies Be Improved?
Maria Mendes, João Sousa, Alberto Pais, Carla Vitorino
February 27, 2023 (v1)
Subject: Biosystems
Keywords: anticancer, biological matrices, celecoxib, in vivo biodistribution, RP-HPLC
Celecoxib, a cyclooxygenase-2 inhibitor (COX-2), is attracting considerable interest owing to its potential anticancer activity. The repurposing strategy of this drug, however, requires preclinical assessment involving the use of increasingly improved analytical methods. In this work, a rapid, accurate, precise, and sensitive reversed-phase high-performance liquid chromatography (RP-HPLC) method was developed for the quantification of celecoxib in five mouse matrices (plasma, brain, spleen, liver, and kidney). Chromatographic separation was achieved within 8 min on a reversed-phase C18 column at 35 °C using a mixture of acetonitrile and 2% (v/v) acetic acid (50:50) as mobile phase, at a flow rate of 0.6 mL/min. Celecoxib and curcumin, as the internal standard, were analyzed at 425 nm and 250 nm, respectively. Linearity was observed (r2 ≥ 0.996) in the concentration ranges selected for celecoxib. Overall precision was below 14.9%, and accuracy was between −14.9% and 13.2%. The acceptanc... [more]
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