bluuebunny/crossref_metadata_2025 huggingface dataset:
Human Joint Torque Estimation Based on Mechanomyography for Upper Extremity Exosuit
Authors: Shi Yongjun , Dong Wei , Lin Weiqi , He Long , Wang Xinrui , Li Pengjie , Gao Yongzhuo
Published: April 2022

Human intention recognition belongs to the algorithm basis for exoskeleton robots to generate synergic movements and provide corresponding assistance. In this article, we acquire and analyze the mechanomyography (MMG) to estimate the current joint torque and apply this method to the rehabilitation training research of the upper extremity exosuit. In order to obtain relatively pure biological signals, a MMG processing method based on the Hilbert-Huang Transform (HHT) is proposed to eliminate the mixed noise and motion artifacts. After extracting features and forming the dataset, a random forest regression (RFR) model is designed to build the mapping relationship between MMG and human joint output through offline learning. In addition, an upper extremity exosuit is constructed for multi-joint assistance. Based on the above research, we develop a torque estimation-based control strategy and make it responsible for the intention understanding and motion servo of this customized system. Finally, an actual test verifies the accuracy and reliability of this recognition algorithm, and an efficiency evaluation experiment also proves the feasibility for power assistance.
Optimal Power Allocation and Cooperative Relaying under Fuzzy Inference System (FIS) Based Downlink PD-NOMA
Authors: Mahmood Asif , Marey Mohamed , Nasralla Moustafa M. , Esmail Maged A. , Zeeshan Muhammad
Published: April 2022

Optimal power allocation (PA) is a decisive part of the power domain non-orthogonal multiple access (PD-NOMA) technique. In PD-NOMA, users are served at the same time and using the same frequency band, but at differing power levels. In this paper, the optimization problem for PA is formulated with distance (d), signal-to-noise ratio (SNR), and foliage depth (df) constraints. A fuzzy inference system (FIS) addresses the optimization problem by allocating the optimal power factors (power levels) to each user in the vicinity of a 5G base-station (gNodeB). The proposed system incorporates a cooperative relaying technique at the near-user to assist the far-user facing signal degradation and greater path losses. A realistic 5G micro-cell is analyzed for downlink PD-NOMA where superposition coding (SC) is used at the transmitter side, a successive interference cancellation (SIC) scheme at the near-user, and a maximum ratio combining (MRC) technique at the far-user’s receiver, respectively. For both simple PD-NOMA and cooperative relaying PD-NOMA, the presented technique’s bit-error-rate (BER) performance is evaluated against various SNR values, and it is concluded that cooperative PD-NOMA outperforms simple PD-NOMA. By combining the presented FIS system with cooperation relaying, the proposed FIS method guarantees user fairness in PD-NOMA systems while also significantly improving performance.
T3OMVP: A Transformer-Based Time and Team Reinforcement Learning Scheme for Observation-Constrained Multi-Vehicle Pursuit in Urban Area
Authors: Yuan Zheng , Wu Tianhao , Wang Qinwen , Yang Yiying , Li Lei , Zhang Lin
Published: April 2022

Smart Internet of Vehicles (IoVs) combined with Artificial Intelligence (AI) will contribute to vehicle decision-making in the Intelligent Transportation System (ITS). Multi-vehicle pursuit (MVP) games, a multi-vehicle cooperative ability to capture mobile targets, are gradually becoming a hot research topic. Although there are some achievements in the field of MVP in the open space environment, the urban area brings complicated road structures and restricted moving spaces as challenges to the resolution of MVP games. We define an observation-constrained MVP (OMVP) problem in this paper and propose a transformer-based time and team reinforcement learning scheme (T3OMVP) to address the problem. First, a new multi-vehicle pursuit model is constructed based on Decentralized Partially Observed Markov Decision Processes (Dec-POMDPs) to instantiate this problem. Second, the QMIX is redefined to deal with the OMVP problem by leveraging the transformer-based observation sequence and combining the vehicle’s observations to reduce the influence of constrained observations. Third, a simulated urban environment is built to verify the proposed scheme. Extensive experimental results demonstrate that the proposed T3OMVP scheme achieves improvements relative to the state-of-the-art QMIX approaches by 9.66~106.25%, from simple to difficult scenarios.
Analysis of Defects and Electrical Characteristics of Variable-Temperature Proton-Irradiated 4H-SiC JBS Diodes
Authors: Zhao Liansheng , Tang Yidan , Bai Yun , Qiu Menglin , Wu Zhikang , Yang Yu , Yang Chengyue , Tian Xiaoli , Liu Xinyu
Published: April 2022

The defects and electrical characteristics of 4H-SiC JBS diodes irradiated by 2 MeV protons under irradiation temperatures of 100–400 K were studied. Forward and reverse current–voltage (I–V), capacitance–voltage (C–V), and deep-level transient spectroscopy (DLTS) measurements were performed to study the changes in the characteristics of the device before and after variable-temperature proton irradiation. As the irradiation temperature increased from 100 to 400 K, the on-resistance decreased from 251 to 204 mΩ, and the carrier concentration gradually increased. The reverse current–voltage experiment results showed that the leakage current increased after proton irradiation at each irradiation temperature compared to before irradiation. The DLTS spectra analyses showed that proton irradiation mainly introduced a carbon vacancy related to the Z1/2 center (E0.68 and E0.72), which may have been the main reason for the changes in the forward and reverse electrical characteristics. The intensity of the DLTS spectrum decreased with the increasing irradiation temperature, indicating that the concentration of defects gradually decreased, due to the increase in the radius of the recombination of a vacancy with a related interstitial atom.
Finite-Time Neural Network Fault-Tolerant Control for Robotic Manipulators under Multiple Constraints
Authors: Zhang Zhao , Peng Lingxi , Zhang Jianing , Wang Xiaowei
Published: April 2022

In this study, a backstepping-based fault-tolerant controller for a robotic manipulator system with input and output constraints was developed. First, a barrier Lyapunov function was adopted to ensure that the system output satisfied time-varying constraints. Subsequently, the actuator input saturation and asymmetric dead-zone characteristics were also considered, and the actuator characteristics were described using a continuous function. The impacts of actuator failures and unknown dynamical parameters of the system were eliminated by employing Gaussian radial basis function neural networks. The external disturbances were compensated for, using a disturbance observer. Meanwhile, a finite-time dynamic surface technique was adopted to accelerate the convergence of the system errors. Finally, simulation of a 2-degrees-of-freedom robotic manipulator system showed the effectiveness of the proposed controller.
ARMatrix: An Interactive Item-to-Rule Matrix for Association Rules Visual Analytics
Authors: Varu Rakshit , Christino Leonardo , Paulovich Fernando V.
Published: April 2022

Amongst the data mining techniques for exploratory analysis, association rule mining is a popular strategy given its ability to find causal rules between items to express regularities in a database. With large datasets, many rules can be generated, and visualization has shown to be instrumental in such scenarios. Despite the relative success, existing visual representations are limited and suffer from analytical capability and low interactive support issues. This paper presents ARMatrix, a visual analytics framework for the analysis of association rules based on an interactive item-to-rule matrix metaphor which aims to help users to navigate sets of rules and get insights about co-occurrence patterns. The usability of the proposed framework is illustrated using two user scenarios and then confirmed from the feedback received through a user test with 20 participants.
Research on Joint Extraction Model of Financial Product Opinion and Entities Based on RoBERTa
Authors: Liao Jiang , Shi Hanxiao
Published: April 2022

With the rapid development of the Internet, and its enormous impact on all aspects of life, traditional financial companies increasingly focus on the user’s online reviews, aiming to promote competitiveness and quality of service in the products of this enterprise. Due to the difficulty of extracting comment text compared with structured data itself, coupled with the fact that it is too colloquial, the traditional model insufficiently semantically represents sentences, resulting in unsatisfactory extraction results. Therefore, this paper selects RoBERTa, a pre-trained language model that has exhibited an excellent performance in recent years, and proposes a joint model of financial product opinion and entities extraction based on RoBERTa multi-layer fusion for the two tasks of opinion and entities extraction. The experimental results show that the performance of the proposed joint model on the financial reviews dataset is significantly better than that of the single model.
Mixed-Integer Linear Programming Model to Assess Lithium-Ion Battery Degradation Cost
Authors: Oliveira Débora B. S. , Glória Luna L. , Kraemer Rodrigo A. S. , Silva Alisson C. , Dias Douglas P. , Oliveira Alice C. , Martins Marcos A. I. , Ludwig Mathias A. , Gruner Victor F. , Schmitz Lenon , Coelho Roberto F.
Published: April 2022

This work proposes a mixed-integer linear programming model for the operational cost function of lithium-ion batteries that should be applied in a microgrid centralized controller. Such a controller aims to supply loads while optimizing the leveled cost of energy, and for that, the cost function of the battery must compete with the cost functions of other energy resources, such as distribution network, dispatchable generators, and renewable sources. In this paper, in order to consider the battery lifetime degradation, the proposed operational cost model is based on the variation in its state of health (SOH). This variation is determined by experimental data that relate the number of charge and discharge cycles to some of the most important factors that degrade the lifespan of lithium-ion batteries, resulting in a simple empirical model that depends on the battery dispatch power and the current state of charge (SOC). As proof-of-concept, hardware-in-the-loop (HIL) simulations of a real microgrid are performed considering a centralized controller with the proposed battery degradation cost function model. The obtained results demonstrate that the proposed cost model properly maintains the charging/discharging rates and the SOC at adequate levels, avoiding accelerating the battery degradation with use. For the different scenarios analyzed, the battery is only dispatched to avoid excess demand charges and to absorb extra power produced by the non-dispatchable resources, while the daily average SOC ranges from 48.86% to 65.87% and the final SOC converges to a value close to 50%, regardless of the initial SOC considered.
Vapour Sorption on Coal: Influence of Polarity and Rank
Authors: Czerw Katarzyna , Krzyżanowski Andrzej , Baran Paweł , Zarębska Katarzyna
Published: April 2022

The surface properties of coal, interactions with gaseous and vapour media, and knowledge of the pore structure are important in terms of preparation, use, and utilisation of coal. This publication combines new unpublished data with analyses included in earlier publications by the research team to expand and systematise information on the sorption of water vapour, methanol vapour, and the saturated and unsaturated hydrocarbons hexane, 1-hexene, heptane, 1-heptene, octane on coals of different ranks. The study showed that the affinity of coal for water and methanol is related to the content of oxygen in the coal rather than the rank of the coal. Water sorption is a multilayer phenomenon, while methanol sorption is a monolayer phenomenon. The water monolayer is greater than that of methanol for low-rank coal, but for the higher-rank coals it is the opposite. The sorption capacity of the applied hydrocarbons depends on the presence or absence of a double bond and the size of the molecule. It increases in the order: n-octane < n-heptane/n-hexane < 1-heptene < 1-hexene. The effect of a double bond is dominant over the influence of the length and shape of the molecule.
Joint Optimization of Energy Storage Sharing and Demand Response in Microgrid Considering Multiple Uncertainties
Authors: Liu Di , Cao Junwei , Liu Mingshuang
Published: April 2022

Energy storage (ES) is playing an increasingly important role in reducing the spatial and temporal power imbalance of supply and demand caused by the uncertainty and periodicity of renewable energy in the microgrid. The utilization efficiency of distributed ES belonging to different entities can be improved through sharing, and considerable flexibility resources can be provided to the microgrid through the coordination of ES sharing and demand response, but its reliability is affected by multiple uncertainties from different sources. In this study, a two-stage ES sharing mechanism is proposed, in which the idle ES capacity is aggregated on the previous day to provide reliable resources for real-time optimization. Then, a two-layer semi-coupled optimization strategy based on a deep deterministic policy gradient is proposed to solve the asynchronous decision problems of day-ahead sharing and intra-day optimization. To deal with the impact of multiple uncertainties, Monte Carlo sampling is applied to ensure that the shared ES capacity is sufficient in any circumstances. Simulation verifies that the local consumption rate of renewable energy is effectively increased by 12.9%, and both microgrid operator and prosumers can improve their revenue through the joint optimization of ES sharing and demand response.
Electrical Life Assessment of the Low-Voltage Circuit Breaker (LVCB) Considering Arc Voltage
Authors: Liu Zhengjun , Wang Li
Published: April 2022

The low-voltage circuit breaker (LVCB) is commonly utilized in the distribution network. An accurate evaluation of its electrical life is related to the safety and reliability of electric energy output. The traditional arc erosion model only considers the effect of current on contact wear while ignoring the impact of operation conditions (supply voltage and power factor) on electrical life. As a result of the arc voltage, the original circuit topology changes, resulting in an early current zero. At 220–660 V AC supply voltages, arc voltage causes the distortion of the breaking current waveform, and the contact erosion amount (CEA) is smaller than that in the ideal case. This work investigates the effect of arc voltage on breaking current, develops an arc erosion model that includes arc voltage, and compares the CEA curves for various supply voltages and power factors. The electrical life of the LVCB is then simulated using the Monte Carlo approach to determine the distribution of electrical life under various operating situations. The results reveal that the LVCB’s electrical life diminishes as the supply voltage increases under the same power factor; it first declines and then increases as the power factor grows under the same supply voltage. For the combination of two parameters (220 V, 0.95) and (660 V, 0.65), the electrical life difference of the LVCB can reach 21.4%. The method solves the low accuracy problem of the LVCB life assessment under different operation conditions. It improves the efficiency of overhaul and maintenance on the LVCB in power distribution systems.
Comprehensive and Integrated Impact Assessment Framework for Development Policies Evaluation: Definition and Application to Kenyan Coffee Sector
Authors: Golinucci Nicolò , Stevanato Nicolò , Namazifard Negar , Tahavori Mohammad Amin , Sulliman Hussain Lamya Adil , Camilli Benedetta , Inzoli Federica , Rocco Matteo Vincenzo , Colombo Emanuela
Published: April 2022

The coexistence of the need to improve economic conditions and the conscious use of environmental resources plays a central role in today’s sustainable development challenge. In this study, a novel integrated framework to evaluate the impact of new technological interventions is presented and an application to smallholder coffee farms and their supply chains in Kenya is proposed. This methodology is able to combine multiple information through the joint use of three approaches: supply chain analysis, input-output analysis, and energy system modeling. Application to the context of the Kenyan coffee sector enables framework validation: shading management measures, the introduction of eco-pulpers, and the exploitation of coffee waste biomass for power generation were compared within a holistic high-level perspective. The implementation of shading practices, carried out with fruit trees, shows the most relevant effects from the economic point of view, providing farmers with an additional source of income and generating $903 of work for every million of local currency (about $9k) invested in this solution. The same investment would save up to 1.46 M m3 of water per year with the eco-pulpers technology. Investing the same amount in coffee-biomass power plants would displace a small portion of production from heavy-duty oil and avoid importing a portion of fertilizer, saving up to 11 tons of CO2 and around $4k per year. The results suggest the optimal allocation of a $100m budget, which can be affected by adding additional constraints on minimum environmental or social targets in line with sustainable development goals.
Modelling, Analysis and Entropy Generation Minimization of Al2O3-Ethylene Glycol Nanofluid Convective Flow inside a Tube
Authors: Mukherjee Sayantan , Aljuwayhel Nawaf F. , Bal Sasmita , Mishra Purna Chandra , Ali Naser
Published: April 2022

Entropy generation is always a matter of concern in a heat transfer system. It denotes the amount of energy lost as a result of irreversibility. As a result, it must be reduced. The present work considers an investigation on the turbulent forced convective heat transfer and entropy generation of Al2O3-Ethylene glycol (EG) nanofluid inside a circular tube subjected to constant wall temperature. The study is focused on the development of an analytical framework by using mathematical models to simulate the characteristics of nanofluids in the as-mentioned thermal system. The simulated result is validated using published data. Further, Genetic algorithm (GA) and DIRECT algorithm are implemented to determine the optimal condition which yields minimum entropy generation. According to the findings, heat transfer increases at a direct proportion to the mass flow, Reynolds number (Re), and volume concentration of nanoparticles. Furthermore, as Re increases, particle concentration should be decreased in order to reduce total entropy generation (TEG) and to improve heat transfer rate of any given particle size. A minimal concentration of nanoparticles is required to reduce TEG when Re is maintained constant. The highest increase in TEG with nanofluids was 2.93 times that of basefluid. The optimum condition for minimum entropy generation is Re = 4000, nanoparticle size = 65 nm, volume concentration = 0.2% and mass flow rate = 0.54 kg/s.
Circular Economy Framework for Energy Recovery in Phytoremediation of Domestic Wastewater
Authors: Mustafa Hauwa Mohammed , Hayder Gasim , Mustapa Siti Indati
Published: April 2022

Circular economy (CE) strategy is crucial in developing towards sustainable growth. It was created to promote resource utilization and the elimination of waste production. This article aimed to study the possibilities of using the CE framework in wastewater bioremediation and energy recovery using hydroponic tanks. The integration of phytoremediation with bioenergy, construction and lifespan of hydroponic tanks in phytoremediation of wastewater, selection of aquatic plants and the expected challenges in the implementation of CE in phytoremediation of wastewater were discussed. The plant-based biomass harvested and the relative growth rate (RGR) of the selected plants from the phytoremediation process was evaluated. The findings obtained indicated that the selected plants tripled in weight after 14 days cultivation period at different retention times. E. crassipes recorded the highest growth with 2.5 ± 0.03 g g−1 d−1, followed by S. molesta with 1.33 ± 0.05 g g−1 d−1 and then P. stratiotes recorded 0.92 ± 0.27 g g−1 d−1 at the end of the cultivation period. Therefore, the selected plants have been identified as having the potential to be used in phytoremediation as well as a source of energy production. The outcome of our review suggested the adoption of a lifecycle assessment as the CE framework for the phytoremediation of wastewater.
An Improved Technique of Hybridization of PSO for the Optimal Coordination of Directional Overcurrent Protection Relays of IEEE Bus System
Authors: Habib Kashif , Lai Xinquan , Wadood Abdul , Khan Shahbaz , Wang Yuheng , Xu Siting
Published: April 2022

The use of a directional overcurrent protection relay (DOPR) to protect an electrical power system is a crucial instrument for keeping the system dynamic and avoiding undue interruption. The coordination of a DOPR’s primary and backup relays is modelled as a highly constrained optimization problem. The goal is to determine an ideal value that will reduce the overall working time of all primary relays. The coordination is accomplished by the use of particle swarm optimization hybridization (HPSO). Comprehensive simulation experiments are carried out to evaluate the efficacy of the proposed HPSO by employing the time multiplier setting (TMS) and plug setting (PS) as an optimization variable and constant, respectively. The HPSO has been examined satisfactorily utilizing certain IEEE benchmark test systems (9-bus and 14-bus). The outcomes are contrasted with earlier heuristics and evolutionary approaches. Based on the acquired findings, it is clear that the obtained results exceed the other conventional and state of the art procedures in terms of total DOPR operation and the computing time necessary to achieve the global optimal solution.
Site Selection for Ocean Thermal Energy Conversion Plants (OTEC): A Case Study in Panama
Authors: Lopez Guillermo , Ortega Del Rosario Maria de los Angeles , James Arthur , Alvarez Humberto
Published: April 2022

This research addressed a need for technical evaluation of the oceanic scenario of Panama for the use of Ocean Thermal Energy Conversion (OTEC). Its bathymetry and location can potentially lead to the exploitation of OTEC, diversifying the energy matrix and helping achieve sustainability. Nevertheless, site selection for OTEC can be a complex task since it involves various alternatives, with different quantitative and qualitative criteria, which may conflict in some cases. Optimization and multiple criteria (MCD) methods have been used lately to address these issues; however, their use is still limited. Here, Analytic Hierarchical Analysis (AHP) is proposed as a MCD method for site selection. Six sites of interest were considered as the alternatives for a plant installment. These sites were chosen, excluding the environmentally and aboriginal protected areas. The quantitative criteria considered were surface and deep-water temperatures, coastline distance, gross and net efficiency. Those variables related to the efficiency, such as the water temperatures, can be considered the most influential, leading to Punta Burica, located on Panama’s Pacific coast, as the best option (96.17%).
Energy Efficiency of Conveyor Belts in Raw Materials Industry
Authors: Bajda Mirosław , Hardygóra Monika , Marasová Daniela
Published: April 2022

Belt conveyors are presently the most common transportation machines used in surface and underground mining [...]
Reference Model Adaptive Control Scheme on PMVG-Based WECS for MPPT under a Real Wind Speed
Authors: Yesudhas Anto Anbarasu , Joo Young Hoon , Lee Seong Ryong
Published: April 2022

Over the last few years, improving power extraction from the wind energy conversion system (WECS) under varying wind speeds has become a complex task. The current study presents the optimum maximum power point tracking (MPPT) control approach integrated with neural network (NN)-based rotor speed control and pitch angle control to extract the maximum power from the WECS. So, this study presents a reference model adaptive control (RMAC) for a direct-drive (DD) permanent magnet vernier generator (PMVG)-based WECS under real wind speed conditions. Initially, the RMAC-based rotor speed tracking control is presented with adaptive terms, which tracks a reference model that guarantees the expected exponential decay of rotor speed error trajectory. Then, to reduce the wind speed measurement errors, a recurrent neural network (RNN)-based training model is presented. Moreover, the asymptotic stability of the proposed control method is mathematically proven by Lyapunov theory. In addition, the pitch angle control is presented to efficiently operate the rotor speed within the allowable operating range. Eventually, the proposed control system demonstrates its effectiveness through simulation and experimentation using a prototype of 5 kW DD PMVG-based WECS. After that, the comparative results affirm the superiority of the proposed control method over existing control methods.
Influence of a Better Prediction of Thermal Satisfaction for the Implementation of an HVAC-Based Demand Response Strategy
Authors: Lim Jongyeon , Choi Wonjun
Published: April 2022

Building system operation faces the challenge of reducing energy use and implementing a demand response, which can be defined as a temporary modification in energy loads affecting dynamic energy price and reliability information. The heating, ventilation, and air-conditioning (HVAC) system in buildings provides an opportunity for implementing demand response strategies due to the thermal inertia in building zones. However, an HVAC-based demand response is not a prevalent strategy in actual facility management due to the lack of understanding among building operators of their facilities and occupants. Herein, we focus on developing a better understanding of the occupant side by obtaining a reliable prediction of occupants’ thermal satisfaction. We evaluate the prediction performance of a probabilistic model provided in our previous paper using a case study with a subset of the ASHRAE Global Thermal Comfort Database II. The influence of a better prediction of thermal satisfaction on the implementation of the HVAC-based demand response strategy is further discussed. The conventional method overestimates productivity deterioration due to changes in the thermal environment, making it challenging to implement an HVAC-based demand response strategy aggressively. A robust prediction model using a probabilistic approach can solve this problem, allowing building operators to adopt an aggressive stance for implementing a demand response. The results of this study offer fresh insight into the impact of a probabilistic model in the prediction of thermal satisfaction for establishing an HVAC-based demand response strategy.
Aerial Identification of Amazonian Palms in High-Density Forest Using Deep Learning
Authors: Marin Willintong , Mondragon Ivan F. , Colorado Julian D.
Published: April 2022

This paper presents an integrated aerial system for the identification of Amazonian Moriche palm (Mauritia flexuosa) in dense forests, by analyzing the UAV-captured RGB imagery using a Mask R-CNN deep learning approach. The model was trained with 478 labeled palms, using the transfer learning technique based on the well-known MS COCO framework©. Comprehensive in-field experiments were conducted in dense forests, yielding a precision identification of 98%. The proposed model is fully automatic and suitable for the identification and inventory of this species above 60 m, under complex climate and soil conditions.
Hematogenesis Adaptation to Long-Term Hypoxia Acclimation in Zebrafish (Danio rerio)
Authors: Shi Linghui , Chen Lei , Jiang Shouwen , Wu Zhichao , Zhou Yan , Xu Qianghua
Published: April 2022

When fish live in the wild or are cultured artificially, they will inevitably suffer from hypoxia. At the same time, blood physiological indexes represent the physiological state of fish. In order to study the effect of long-term hypoxia acclimation on fish hematogenesis, we cultured zebrafish embryos into adulthood in a hypoxia incubator (1.5 ± 0.2 mg/L). Then we compared the hematological parameters of zebrafish cultured in normoxia and hypoxia conditions. Transcriptome sequencing analysis of the main hematopoietic tissue, the head kidney, was also compared between the two groups. Results showed that the number of erythrocytes increased significantly in the long-term hypoxia acclimated group, while the size of several cell types, such as red blood cells, eosinophils, basophils, small lymphocytes and thrombocytes, decreased significantly. The transcriptomic comparisons revealed that there were 6475 differentially expressed genes (DEGs) between the two groups. A Gene Ontology (GO) annotation and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis showed that hematopoiesis and cell proliferation signaling were the most significantly enriched pathways in the head kidney of hypoxia acclimated zebrafish. In addition, many genes involved in the hematopoietic process showed significantly higher levels of expression in the hypoxia acclimated zebrafish, when compared to the normoxia zebrafish. When considered together, these data allowed us to conclude that long-term hypoxia can promote the hematopoiesis process and cell proliferation signaling in the zebrafish head kidney, which resulted in higher red blood cell production. Higher numbers of red blood cells allow for better adaptation to the hypoxic environment. In conclusion, this study provides a basis for the in-depth understanding of the effects of hypoxia on hematogenesis in fish species.
Optimization of a Micromixer with Automatic Differentiation
Authors: Jeßberger Julius , Marquardt Jan E. , Heim Luca , Mangold Jakob , Bukreev Fedor , Krause Mathias J.
Published: April 2022

As micromixers offer the cheap and simple mixing of fluids and suspensions, they have become a key device in microfluidics. Their mixing performance can be significantly increased by periodically varying the inlet pressure, which leads to a non-static flow and improved mixing process. In this work, a micromixer with a T-junction and a meandering channel is considered. A periodic pulse function for the inlet pressure is numerically optimized with regard to frequency, amplitude and shape. Thereunto, fluid flow and adsorptive concentration are simulated three-dimensionally with a lattice Boltzmann method (LBM) in OpenLB. Its implementation is then combined with forward automatic differentiation (AD), which allows for the generic application of fast gradient-based optimization schemes. The mixing quality is shown to be increased by 21.4% in comparison to the static, passive regime. Methodically, the results confirm the suitability of the combination of LBM and AD to solve process-scale optimization problems and the improved accuracy of AD over difference quotient approaches in this context.
Modeling and Parameterization of the Evaporation and Thermal Decomposition of an Iron(III) Nitrate Nonahydrate/Ethanol Droplet for Flame Spray Pyrolysis
Authors: Narasu Praveen , Gutheil Eva
Published: April 2022

Flame spray pyrolysis (FSP) is a promising approach to generate nanoparticles from precursor solutions, where the convective droplet heating and evaporation of the single precursor solution droplet play a key role. Depending on the precursor solution under consideration, reactions inside the liquid may occur. The present numerical study concerns the heating, evaporation, and thermal decomposition of single droplets of iron(III) nitrate nonahydrate (INN) and ethanol at an initial temperature of 293.15 K in hot convective air at atmospheric pressure. If the ambience is below the thermal decomposition temperature (Tth) of the INN, iron nitrate particles are directly formed inside the particle, whereas at ambient temperatures beyond Tth, the iron nitrate thermally decomposes into gaseous Fe2O3 and N2O5. Vaporization and thermal decomposition govern the process, depending on the droplet surface temperature. If the ambient temperature is larger than a specific value T+, thermal decomposition is very fast and vaporization dominates the total process time, whereas at lower ambient temperatures, the vaporization is slower, which causes a lower final droplet surface temperature, leading to considerably longer thermal decomposition, which dominates the total process time under that condition. The ambient temperature at which this reversed behavior occurs depends on initial INN loading of the particle and the relative velocity but is largely independent of the initial droplet size. These new results are very useful in choosing the process temperature, which is recommended to lie beyond the ambient air temperature of T+ to assure that the total process time is kept short. The numerical results are parameterized for use in more complex simulations of FSP.
Production, Processing, and Protection of Microalgal n-3 PUFA-Rich Oil
Authors: Ren Xiang , Liu Yanjun , Fan Chao , Hong Hao , Wu Wenzhong , Zhang Wei , Wang Yanwen
Published: April 2022

Microalgae have been increasingly considered as a sustainable “biofactory” with huge potentials to fill up the current and future shortages of food and nutrition. They have become an economically and technologically viable solution to produce a great diversity of high-value bioactive compounds, including n-3 polyunsaturated fatty acids (PUFA). The n-3 PUFA, especially eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), possess an array of biological activities and positively affect a number of diseases, including cardiovascular and neurodegenerative disorders. As such, the global market of n-3 PUFA has been increasing at a fast pace in the past two decades. Nowadays, the supply of n-3 PUFA is facing serious challenges as a result of global warming and maximal/over marine fisheries catches. Although increasing rapidly in recent years, aquaculture as an alternative source of n-3 PUFA appears insufficient to meet the fast increase in consumption and market demand. Therefore, the cultivation of microalgae stands out as a potential solution to meet the shortages of the n-3 PUFA market and provides unique fatty acids for the special groups of the population. This review focuses on the biosynthesis pathways and recombinant engineering approaches that can be used to enhance the production of n-3 PUFA, the impact of environmental conditions in heterotrophic cultivation on n-3 PUFA production, and the technologies that have been applied in the food industry to extract and purify oil in microalgae and protect n-3 PUFA from oxidation.
Bioactive Properties, Volatile Compounds, and Sensory Profile of Sauerkraut Are Dependent on Cultivar Choice and Storage Conditions
Authors: Major Nikola , Bažon Iva , Išić Nina , Kovačević Tvrtko Karlo , Ban Dean , Radeka Sanja , Goreta Ban Smiljana
Published: April 2022

Sauerkraut is produced by cabbage fermentation either spontaneously or by adding lactic acid bacteria. Although commercial cabbage cultivars are more desirable due to their higher yield and uniformity, traditional cultivars are highly prized for their unique sensory characteristics and suitability for fermentation. The aim of this study was to investigate the properties of sauerkrauts from traditional cabbage cultivars (‘Brgujski’ and ‘Žminjski’) compared to commercial samples, and to unravel the effects of ambient (18 °C) and cold storage (4 °C) on sauerkraut properties. Higher total phenolic contents and total antioxidant capacities measured by both FRAP and DPPH methods were observed for sauerkrauts from traditional cultivars. In total, 32 volatile compounds were identified, and differences in the volatile profile were observed among the investigated sauerkrauts. The sensory properties of traditional cabbage cultivars were on par, or even better, compared to those of commercially available sauerkraut products. The cold storage conditions characteristic of commercial environments preserved the total antioxidant capacity, the red to green color ratio (a), as well as the lightness (L) of sauerkraut compared to the ambient temperatures characteristic of domestic conditions, indicating the preservation of bioactive compounds responsible for the purple cabbage head coloration of the investigated traditional cultivars.
Nonlocal ψ-Hilfer Generalized Proportional Boundary Value Problems for Fractional Differential Equations and Inclusions
Authors: Ntouyas Sotiris , Ahmad Bashir , Tariboon Jessada
Published: April 2022

In this paper, we establish existence and uniqueness results for a new class of boundary value problems involving the ψ-Hilfer generalized proportional fractional derivative operator, supplemented with mixed nonlocal boundary conditions including multipoint, fractional integral multiorder and derivative multiorder operators. The given problem is first converted into an equivalent fixed point problem, which is then solved by means of the standard fixed point theorems. The Banach contraction mapping principle is used to establish the existence of a unique solution, while the Krasnosel’skiĭ and Schaefer fixed point theorems as well as the Leray–Schauder nonlinear alternative are applied for obtaining the existence results. We also discuss the multivalued analogue of the problem at hand. The existence results for convex- and nonconvex-valued multifunctions are respectively proved by means of the Leray–Schauder nonlinear alternative for multivalued maps and Covitz–Nadler’s fixed point theorem for contractive multivalued maps. Numerical examples illustrating the obtained results are also presented.
Medical Records in Community Pharmacies: The Cases of UK and Australia
Authors: Pires Carla
Published: April 2022

Background: Lack of access to patients’ digital health records by community pharmacists can negatively impact pharmaceutical care. Access to these records by community pharmacists is only available in some countries. Thus, the study aim was to compare and discuss the shared patients’ health records between the National Health Systems and Community Pharmacies in UK and Australia. Methods: Two platforms were selected: Summary Care Records (SCR) (UK) and My Health Record (MyHR) (Australia). A qualitative and descriptive study was carried out. The type of shared health records was collected in public/official websites. Qualitative classifiers/descriptors were created to classify the shared health records. Results: The common classifiers/descriptors between both SCR and MyHR were medicines, medicines/immunization, and medical history. However, MyHR seems to comprise more details/information, such as patient’s discharge summaries, specialist letters, or documents to communicate significant patient information from one healthcare provider to another. Conclusion: Community pharmacists can update or consult SCR and MyHR to provide direct patient care in UK and Australia, respectively. The profile of shared health records with community pharmacies was not equal between SCR (UK) and MyHR (Australia). More studies are recommended to evaluate the benefits and risks of using these platforms on patients’ outcomes.
The Tracking Control of the Variable-Order Fractional Differential Systems by Time-Varying Sliding-Mode Control Approach
Authors: Jiang Jingfei , Xu Xin , Zhao Kun , Guirao Juan L. G. , Saeed Tareq , Chen Huatao
Published: April 2022

This paper is concerned with the problem of tracking control for a class of variable-order fractional uncertain system. In order to realize the global robustness of systems, two types of controllers are designed by the global sliding-mode control method. The first one is based on a full-order global sliding-mode surface with variable-order fractional type, and the control law is continuous, which is free of chattering. The other one is a novel time-varying control law, which drives the error signals to stay on the proposed reduced-order sliding-mode surface and then converges to the origin. The stability of the controllers proposed is proved by the use of the variable-order fractional type Lyapunov stability theorem and the numerical simulation is given to validate the effectiveness of the theoretical results.
Epidemic Dynamics of a Fractional-Order SIR Weighted Network Model and Its Targeted Immunity Control
Authors: Liu Na , Fang Jie , Sun Junwei , Li Sanyi
Published: April 2022

With outbreaks of epidemics, an enormous loss of life and property has been caused. Based on the influence of disease transmission and information propagation on the transmission characteristics of infectious diseases, in this paper, a fractional-order SIR epidemic model is put forward on a two-layer weighted network. The local stability of the disease-free equilibrium is investigated. Moreover, a conclusion is obtained that there is no endemic equilibrium. Since the elderly and the children have fewer social tiers, a targeted immunity control that is based on age structure is proposed. Finally, an example is presented to demonstrate the effectiveness of the theoretical results. These studies contribute to a more comprehensive understanding of the epidemic transmission mechanism and play a positive guiding role in the prevention and control of some epidemics.
Some New Inequalities on Laplace–Stieltjes Transforms Involving Logarithmic Growth
Authors: Xu Hongyan , Li Hong , Xuan Zuxing
Published: April 2022

This article is devoted to exploring the properties on the logarithmic growth of entire functions represented by Laplace–Stieltjes transforms of zero order. In order to describe the growth of Laplace–Stieltjes transforms more finely, we introduce some concepts of the logarithmic indexes of the maximum term and the center index of the maximum term of Laplace–Stieltjes transforms, and establish some new inequalities focusing on the above logarithmic indexes, the logarithmic order, the (lower) logarithmic type and the coefficients of Laplace–Stieltjes transforms. Moreover, we obtain two estimation forms on the (lower) logarithmic type of entire functions represented by Laplace–Stieltjes transform by applying these inequalities. One estimation is mainly by the center indexes of the maximum term, the other is by the logarithmic order, exponent and coefficients. Finally, we obtain the equivalence condition of entire functions with the perfectly logarithmic linear growth. This result shows that the two estimation forms can be equivalent to some extent.
Nonlocal Coupled System for (k,φ)-Hilfer Fractional Differential Equations
Authors: Samadi Ayub , Ntouyas Sotiris K. , Tariboon Jessada
Published: April 2022

In this paper, we study a coupled system consisting of (k,φ)-Hilfer fractional differential equations of the order (1,2], supplemented with nonlocal coupled multi-point boundary conditions. The existence and uniqueness of the results are established via Banach’s contraction mapping principle, the Leray–Schauder alternative and Krasnosel’skiĭ’s fixed-point theorem. Numerical examples are constructed to illustrate the obtained results.
Evaluation of Immune Status in Two Cohorts of Atlantic Salmon Raised in Different Aquaculture Systems (Case Study)
Authors: Lund Hege , Bakke Anne , Boysen Preben , Afanasyev Sergey , Rebl Alexander , Manji Farah , Ritchie Gordon , Krasnov Aleksei
Published: April 2022

Assessment of immune competence of farmed Atlantic salmon is especially important during smoltification and the first several months in the sea. Recently developed tools were applied to salmon raised in a traditional flow-through facility (FT, cohort 1) and in a recirculation aquaculture system (RAS, cohort 2). Fish were sampled at four time-points: parr, smolt, and at three weeks and three months after seawater transfer (SWT); expression of 85 selected immune and stress genes, IgM transcripts (Ig-seq), and circulating antibodies were analyzed. A steady increase in gene expression was seen over time in gill and spleen in both cohorts, and especially in antiviral and inflammatory genes in the gill. Differences between the cohorts were greatest in the dorsal fin but later leveled off. Comparison with a gill reference dataset found a deviation in only three of 85 fish, suggesting a good immune status in both cohorts. Levels of both specific and nonspecific antibodies were higher in cohort 2 in smolts and in growers three weeks after SWT; however, levels evened out after three months in the sea. Ig-seq indicated association between antibody production, expansion of the largest clonotypes, and massive migration of B cells from spleen to gill in smolts. The results suggested greater agitation and higher reactivity of the immune system in RAS-produced salmon, but the difference between the cohorts leveled off over time.
Double-Stranded Break Repair in Mammalian Cells and Precise Genome Editing
Authors: Ali Akhtar , Xiao Wei , Babar Masroor Ellahi , Bi Yanzhen
Published: April 2022

In mammalian cells, double-strand breaks (DSBs) are repaired predominantly by error-prone non-homologous end joining (NHEJ), but less prevalently by error-free template-dependent homologous recombination (HR). DSB repair pathway selection is the bedrock for genome editing. NHEJ results in random mutations when repairing DSB, while HR induces high-fidelity sequence-specific variations, but with an undesirable low efficiency. In this review, we first discuss the latest insights into the action mode of NHEJ and HR in a panoramic view. We then propose the future direction of genome editing by virtue of these advancements. We suggest that by switching NHEJ to HR, full fidelity genome editing and robust gene knock-in could be enabled. We also envision that RNA molecules could be repurposed by RNA-templated DSB repair to mediate precise genetic editing.
Association of SNP rs5069 in APOA1 with Benign Breast Diseases in a Mexican Population
Authors: Domínguez-Díaz Carolina , Morán-Moguel María Cristina , Navarro-Hernandez Rosa Elena , Romo-Vázquez Rebeca , Mendizabal-Ruiz Adriana Patricia
Published: April 2022

Breast cancer (BCa) is the most common type of cancer affecting women worldwide. Some histological subtypes of benign breast disease (BBD) are considered risk factors for developing BCa. Single nucleotide polymorphisms (SNPs) in the genes encoding apolipoproteins A-I (APOA1) and B (APOB) have been associated with BCa in Tunisian, Chinese, and Taiwanese populations. The objective of this pilot study is to evaluate the possible contribution of APOA1 and APOB polymorphisms to BCa and BBD in the Mexican population. We analyzed the association of 4 SNPs in genes encoding apolipoproteins: rs670 and rs5069 in the APOA1 gene, and rs693 and rs1042031 in the APOB gene, by performing PCR-RFLP with DNA extracted from the biopsy tissue of Mexican women with BCa or BBD and whole blood samples obtained from the general population (GP). Our results showed an association between the CT + TT genotypes of the SNP rs5069 and BBD (p = 0.03201). In the A-T haplotype, the frequency of the SNPs rs670 and rs5069 differed significantly between the BBD group and the GP and BCa groups (p = 0.004111; p = 0.01303). In conclusion, the SNP rs5069 is associated with BBD but not with BCa in the Mexican population.