bluuebunny/crossref_metadata_2025 huggingface dataset:
Determinants of COVID-19-related knowledge and preventive behaviours among students in reopened secondary schools: cross-sectional study
Authors: Handebo Simegnew , Adugna Asmamaw , Kassie Ayenew , Shitu Kegnie
Published: April 2021

Purpose

In Ethiopia, more than 26 million students have been out of the classroom for nearly 9 months. On 18 September, the Ethiopian Minister of Health advised the Parliament the possibility of reopening schools provided certain conditions were met. Schools are currently reopening in the country for the first time since March 2020.

Objective

This study assessed the knowledge and preventive health behaviours toward COVID-19 and associated factors among secondary school students.

Design, setting, participants and outcome measures

An institution-based cross-sectional study was conducted from October to December 2020 in Gondar city, Northwest Ethiopia. A total of 370 secondary school students were included. Bivariable and multivariable ordinal logistic regression model were fitted to identify the predictors of knowledge about COVID-19. Simple and multiple linear regression analysis were done to identify factors associated with preventive behaviour. A p<0.05 was used to declare statistical significance.

Results

Only one-fourth (23.5%, 95% CI 19.5% to 28.1%) of the participants had a good knowledge about COVID-19. The mean score of preventive behaviour was 22.8±SD 6.2. Marital status, religion, father education, living arrangement and sources of information were significantly associated with knowledge about COVID-19. Being female and using health professionals as source of information increased the engagement in preventive behaviours. On the other hand, student whose father employed in non-governmental organisation and other jobs had decreased engagement in preventive health behaviours.

Conclusion

Significant number of the students had inadequate knowledge about COVID-19 and poorly engaged in COVID-19 preventive behaviour. Thus, it is suggested to include and disseminate about COVID-19 in related academic sessions, using school clubs and minimedias. The sources of COVID-19-related information need to strengthen the dissemination of tailored, credible and timely message to enhance the knowledge and engagement of the students in preventive behaviours.
Recovery of Iridium by Solvent Extraction and Direct Electrodeposition Using Phosphonium-Based Ionic Liquids
Authors: Matsumiya Masahiko , Kinoshita Ryoma , Tsuchida Yusuke , Sasaki Yuji
Published: April 2021

The extraction behavior of Ir(IV) in a phosphonium-based ionic liquid (IL) system, triethyl-n-pentyl phosphonium bis(trifluoromethyl-sulfonyl)amide ([P2225][NTf2]), was investigated using an amine extractant. In addition, the electrochemical behavior of the extracted Ir(IV) species in [P2225][NTf2] during electrodeposition was studied. Voltammetry-based electrochemical analysis revealed that the reduction of Ir(IV) proceeded via an intermediate Ir(III) species in two steps, namely, Ir(IV) + e− → Ir(III) and Ir(III) + 3e− → Ir(0). Diffusion coefficients of the extracted Ir(IV) species in the IL were determined over the temperature range of 298–373 K using semi-integral and semi-differential analyses, and values obtained from the two analyses were consistent with each other. Furthermore, consecutive solvent extraction and electrodeposition of Ir metal in the IL bath were performed for 10 cycles. The entire Ir electrodeposit was in the metallic state, as is evident from the 4f
7/2 spectrum obtained by XPS.
A Critical Examination of the Mott–Schottky Model of Grain-Boundary Space-Charge Layers in Oxide-Ion Conductors
Authors: Usler Adrian L. , De Souza Roger A.
Published: April 2021

The electrical properties of grain boundaries in ionic conductors are studied most frequently and most easily by Electrochemical Impedance Spectroscopy (EIS). The resistance data obtained in this manner are typically analyzed with the Mott–Schottky space-charge model to extract a space-charge potential. In this study, taking CeO2 containing acceptor-dopant cations and oxygen vacancies as our model system, we calculate impedance spectra by solving the drift–diffusion equation for oxygen vacancies for a bicrystal geometry with space-charge layers at the grain boundary. Three different cases are considered for the behavior of the acceptor-dopant cations: a uniform distribution (Mott–Schottky), an equilibrium distribution (Gouy–Chapman), and a distribution frozen-in from a much higher temperature (restricted equilibrium). Analyzing our impedance data for the restricted-equilibrium case with the Mott–Schottky model, we find that the obtained space-charge potentials are substantially underestimated. In view of such a discrepancy not normally being apparent (the true values being unknown), we propose a specific set of EIS experiments that allow the Mott–Schottky model to be discounted.
New Inexpensive Simple Experimental Setup for Anodic Bonding of Silicon-Glass
Authors: Sundaresh Sreeram , Deshpande Mamatha G. , Sundaram Kalpathy B.
Published: April 2021

A new reliable, simple, inexpensive experimental setup was built to bond silicon (Si)-glass by anodic bonding under atmospheric conditions. Anodic bonding of silicon-glass samples was carried out using a custom in-house-built inexpensive setup. The bonding tensile strength test confirmed that anodic bonding strongly depends on both the bonding temperature and the bonding voltage. The bonding tensile strength was found to be 1134 × 104 Nm−2 at a temperature of 420 °C and an applied voltage of 800 V. It has also been concluded from this study that to achieve reasonable bond-tensile strength, the typical temperature and voltage to bond Si-Glass is 385 °C and 700 V, respectively.
Antioxidant Activities of Commiphora leptophloeos (Mart.) J. B. Gillett) (Burseraceae) Leaf Extracts Using In Vitro and In Vivo Assays
Authors: Cordeiro Maria Lúcia da Silva , Ribeiro Ana Raquel Carneiro , Melo Luciana Fentanes Moura de , Silva Lucas Felipe da , Fidelis Gabriel Pereira , Silva Larissa Marina Pereira , Caland Ricardo Basílio de Oliveira , Cadavid Cesar Orlando Muñoz , Aragão Cícero Flavio Soares , Zucolotto Silvana Maria , Oliveira Riva de Paula , dos Santos Deborah Yara Alves Cursino , Rocha Hugo Alexandre Oliveira , Scortecci Katia Castanho
Published: April 2021

Commiphora leptophloeos is widely used in folk medicine without any scientific basis. Considering this, the aim of this study was to evaluate the chemical profile and the antioxidant activity of C. leptophloeos leaf extracts using in vitro and in vivo assays. Six extracts were obtained from fresh leaves using a serial extraction (nonpolar to polar solvents). These extracts were first evaluated with the presence of phytochemical compounds using the methods thin layer chromatography (TLC), ultrahigh performance liquid chromatography (UHPLC‐DAD), and high performance liquid chromatography, both with diode array detection (HPLC‐DAD). Based on the compounds identified, it was used some bioinformatics tools in order to identify possible pathway and gene targets. After that, the antioxidant capacity from these extracts was analysed by in vitro assays and in vivo assays using Caenorhabditis elegans model. Phytochemical analyses showed the presence of polyphenols, such as rutin, vitexin, and quercetin diglycosides in all extracts, especially in ethanol extract (EE) and methanol extract (EM). Bioinformatics analysis showed these polyphenols linked to antioxidant pathways. Furthermore, EE and EM displayed a high antioxidant capacity in DPPH and superoxide radical scavenging assays. They also had no effect on cell viability for 3T3 nontumour cell. However, for B16‐F10 tumour cell lines, these extracts had toxicity effect. In vivo assays using C. elegans N2 showed that EE was not toxic, and it did not affect its viability nor its development. Besides, EE increased worm survival under oxidative stress and reduced intracellular reactive oxygen species (ROS) levels by 50%. Thus, C. leptophloeos EE displayed an important in vitro and in vivo antioxidant capacity. The EE extract has polyphenols, suggesting that these compounds may be responsible for a myriad of biological activities having this potential to be used in various biotechnological applications.
Diagnosis of Alzheimer’s Disease by Time-Dependent Power Spectrum Descriptors and Convolutional Neural Network Using EEG Signal
Authors: Amini Morteza , Pedram Mir Mohsen , Moradi AliReza , Ouchani Mahshad
Published: April 2021

Using strategies that obtain biomarkers where early symptoms coincide, the early detection of Alzheimer’s disease and its complications is essential. Electroencephalogram is a technology that allows thousands of neurons with equal spatial orientation of the duration of cerebral cortex electrical activity to be registered by postsynaptic potential. Therefore, in this paper, the time-dependent power spectrum descriptors are used to diagnose the electroencephalogram signal function from three groups: mild cognitive impairment, Alzheimer’s disease, and healthy control test samples. The final feature used in three modes of traditional classification methods is recorded:

k

-nearest neighbors, support vector machine, linear discriminant analysis approaches, and documented results. Finally, for Alzheimer’s disease patient classification, the convolutional neural network architecture is presented. The results are indicated using output assessment. For the convolutional neural network approach, the accurate meaning of accuracy is 82.3%. 85% of mild cognitive impairment cases are accurately detected in-depth, but 89.1% of the Alzheimer’s disease and 75% of the healthy population are correctly diagnosed. The presented convolutional neural network outperforms other approaches because performance and the

k

-nearest neighbors’ approach is the next target. The linear discriminant analysis and support vector machine were at the low area under the curve values.
Library-Based Overview of Multicriteria Decision Making for Continuous Software Improvement for Internet of Software Industry
Authors: Xiaolong He , Nazir Shah , Lunchao Zhong , Jun Deng
Published: April 2021

The revolution in software development is increasing with the use of advanced techniques and tools. Software development organizations are considering standards, methods, approaches, and tools to support them in maintaining the effectiveness of software. An effective implementation of software process improvement (SPI) is important in order to gain effectiveness in the software industry. Disasters are happening in software projects and industry of software, which hinder the success of software and ultimately lead the software to failure. Peoples of organizations are demanding to devise methodological approaches for reducing the failure rate of software, but it perceived slight success. The proposed study’s aim is to offer multicriteria decision making for continuous Internet of software industry and to report the literature to early decision making associated to software developments. The study has devised a comprehensive overview of the existing methodological approaches, tools, and mechanisms applied in software improvement for the software industry and is based on multicriteria decision making. The research has analyzed the available literature from different perspectives and then reported it. The results of the study will help researchers to devise new solutions for effective software process improvement, and the this study will consider as a support of evidence.
Automatic Retinal Vessel Segmentation Based on an Improved U-Net Approach
Authors: Huang Zihe , Fang Ying , Huang He , Xu Xiaomei , Wang Jiwei , Lai Xiaobo
Published: April 2021

Retinal blood vessels are the only deep microvessels in the blood circulation system that can be observed directly and noninvasively, providing us with a means of observing vascular pathologies. Cardiovascular and cerebrovascular diseases, such as glaucoma and diabetes, can cause structural changes in the retinal microvascular network. Therefore, the study of effective retinal vessel segmentation methods is of great significance for the early diagnosis of cardiovascular diseases and the vascular network’s quantitative results. This paper proposes an automatic retinal vessel segmentation method based on an improved U-Net network. Firstly, the image patches are rotated to amplify the image data, and then, the RGB fundus image is preprocessed by normalization. Secondly, after the improved U-Net model is constructed with 23 convolutional layers, 4 pooling layers, 4 upsampling layers, 2 dropout layers, and Squeeze and Excitation (SE) block, the extracted image patches are utilized for training the model. Finally, the fundus images are segmented through the trained model to achieve precise extraction of retinal blood vessels. According to experimental results, the accuracy of 0.9701, 0.9683, and 0.9698, sensitivity of 0.8011, 0.6329, and 0.7478, specificity of 0.9849, 0.9967, and 0.9895, F1-Score of 0.8099, 0.8049, and 0.8013, and area under the curve (AUC) of 0.8895, 0.8845, and 0.8686 were achieved on DRIVE, STARE, and HRF databases, respectively, which is better than most classical algorithms.
Experimental Study of Reinforcing Broken Gangues by Colloid Cement Slurry
Authors: Lyu Xin , Yang Ke , Fu Qiang , Wei Zhen , Liu Shuai
Published: April 2021

Studies on jet grouting materials mainly focus on the aggregates in cement or the environment where they are maintained and rarely deal with the cohesiveness, reinforcement load‐bearing characteristics, and surface spalling. In this study, cement slurries with different colloid contents were prepared to explore the characteristics and reinforcement effect of broken gangues. These were then subjected to mechanical testing to measure the strength and axial strain performance, and the failure modes and failure patterns were discussed. The results indicated that the colloid component has a significant strengthening effect on the early strength of the samples. As the age increased, the sample axial strain and elastic modulus of the colloid cement paste increased as the colloid component provides viscoelasticity when it resists deformation. The sample strength of cement paste decreases after the addition of broken gangue while the strength of class E samples increases significantly during each age. The cement paste sample showed penetrating splitting failure, the colloidal component effectively controlled the peeling of sample surface, and the failure mode after adding gangue was relatively complicated. The instability modes of the samples are divided into dispersed load‐bearing instability and cumulative load‐bearing instability, and the content of colloid components affects the failure mode of the samples. A colloid component proportion of 23.33% is the optimal choice, which has an obvious reinforcement effect on the broken gangue.
Fault Diagnosis of Subway Traction Motor Bearing Based on Information Fusion under Variable Working Conditions
Authors: Xu Yanwei , Cai Weiwei , Xie Tancheng
Published: April 2021

Under the variable working condition, the fault signal of the rolling bearing contains rich characteristic information. In view of the problem that the traditional fault diagnosis method of the rolling bearing depends on the prior knowledge and expert experience too much and the low recognition rate of some faults with the single signal, one method of rolling bearing fault diagnosis based on information fusion under the variable working condition is proposed. Firstly, one test and multi‐information acquisition system of the rolling bearing is built. Secondly, the metro traction motor bearing nu216 is selected as the research object, and to prefabricate the defects, the data of acoustic emission and vibration acceleration signals during the test of the bearing is acquired. Then, the original signal is processed and extracted by the wavelet packet decomposition, and the normalized feature information is fused by the convolution neural network. Finally, the two‐dimensional convolution neural network model is established to diagnose the bearing fault of the metro traction motor under different conditions. The test results show that the intelligent fault diagnosis method of the subway traction motor bearing based on information fusion under variable working conditions can accurately identify the fault type of the bearing, while the load and speed change. When the neural network training set and the test set cover the same working conditions, the accuracy can reach 100%.
Dynamic Stochastic Optimization of Emergent Blood Collection and Distribution from Supply Chain Perspective
Authors: Jin Xiangyu , Tang Huajun , Huang Yuxin
Published: April 2021

In response to emergencies, it is critical to investigate how to deliver emergency supplies efficiently and securely to disaster‐affected areas and people. There is no doubt that blood is deemed one of the vital relief supplies, and ensuring smooth blood delivery may substantially alleviate subsequent impacts caused by the disaster. Taking red blood cell products as the research object, this work proposes a four‐echelon blood supply chain model. Specifically, it includes blood donors, blood donation houses, blood centres, and hospitals. Furthermore, numerical analysis is provided to test the feasibility of blood collection and distribution schemes and conduct sensitivity analysis to test the impacts of the relevant parameters (e.g., apheresis donation proportion of red blood cells (RBCs), distance between blood donors and blood facilities, and times of blood donation) on the scheme. This research provides some scientific and reasonable support for decision makers and managerial implications for emergency departments and contributes to the study of emergent blood supply chain.
Disturbance Effect of Pipe Jacking Group Adjacent Excavation on Surrounding Soil
Authors: Wang Changbai , Liu Jimin , Cheng Hua , Cai Haibing
Published: April 2021

Under the modern and complicated urban environment, clarifying the interaction mechanism and mutual influence mechanism between the urban tunnel and the surrounding environment is of considerable significance to the construction and operation of the tunnel. To understand and grasp the excavation‐induced disturbance range and mechanism of adjacent pipeline jacking group on surrounding soils, this paper carries out relevant researches. Based on a case history of a three‐hole parallel adjacent jacking pipeline in shallow overburden, a field test and assessment are performed. By setting monitoring points around the monitoring section, the earth pressure and water pressure under different buried depths and different spacing are monitored. For further discussion, the general law of soil disturbance around single‐hole, double‐hole, and three‐hole jacking is investigated, the calculation method of lateral disturbance range and overlapping area range of pipe jacking group is deduced, and the degree of soil disturbance is evaluated as well. The results show that there will be different degrees of disturbance superposition in parallel multihole jacking due to the influence of the spacing, and the disturbance intensity is greatly affected by the parallel distance and buried depth.
On Best Approximations in Hyperconvex Spaces
Authors: George Reny , Mitrović Zoran D. , Aydi Hassen
Published: April 2021

In this manuscript, we present further extensions of the best approximation theorem in hyperconvex spaces obtained by Khamsi.
Delayed Calcium Normalization after Successful Parathyroidectomy in Primary Hyperparathyroidism
Authors: de la Cruz Rodríguez Iván Emilio , García Montesinos Elsy Sarahí , Rodríguez-Delgado María Fernanda , Vargas Ortega Guadalupe , Hernández Lourdes Balcázar , Zubieta Victoria Mendoza , Avendaño Victor Hernández , Virla Baldomero González
Published: April 2021

Introduction. Parathyroidectomy is the curative treatment option in primary hyperparathyroidism (PHPT). The decrease of parathormone (PTH) by 50% or more from levels prior to surgery after excision predicts successful parathyroidectomy. Serum calcium is expected to return to normal within 24–72 hours after the surgery; however, nearly 10% have transient, persistent postoperative hypercalcemia. We present a case report of delayed calcium normalization after successful parathyroidectomy in a 38-year-old patient with PHPT. Methods. Parathyroidectomy was performed, with evidence of a decrease in PTH levels of more than 50% in the first 24 hours postoperatively compared to presurgical PTH; however, despite curative parathyroidectomy, a delayed calcium normalization was evidenced, with hypercalcemia persistence up to 120 hours postoperatively. Results. After the first month postoperatively, serum calcium remained normal. In conclusion, approximately 10% of patients with curative parathyroidectomy have transient, persistent postoperative hypercalcemia, which is more likely to occur in patients with higher preoperative serum calcium and PTH levels. Conclusion. Persistent hypercalcemia after the first month postoperatively is related with persistent PHPT, highlighting the importance of calcium monitoring after parathyroidectomy to predict short-term, medium-term, and long-term outcomes and prognosis.
Fairness of Task Allocation in Crowdsourcing Workflows
Authors: Fu Donglai , Liu Yanhua
Published: April 2021

Fairness plays a vital role in crowd computing by attracting its workers. The power of crowd computing stems from a large number of workers potentially available to provide high quality of service and reduce costs. An important challenge in the crowdsourcing market today is the task allocation of crowdsourcing workflows. Requester-centric task allocation algorithms aim to maximize the completion quality of the entire workflow and minimize its total cost, which are discriminatory for workers. The crowdsourcing workflow needs to balance two objectives, namely, fairness and cost. In this study, we propose an alternative greedy approach with four heuristic strategies to address such an issue. In particular, the proposed approach aims to monitor the current status of workflow execution and use heuristic strategies to adjust the parameters of task allocation. We design a two-phase allocation model to accurately match the tasks with workers. The F-Aware allocates each task to the worker that maximizes the fairness and minimizes the cost. We conduct extensive experiments to quantitatively evaluate the proposed algorithms in terms of running time, fairness, and cost by using a customer objective function on the WorkflowSim, a well-known cloud simulation tool. Experimental results based on real-world workflows show that the F-Aware, which is 1% better than the best competitor algorithm, outperforms other optimal solutions in finding the tradeoff between fairness and cost.
Hermetia illucens Protein Conjugated with Glucose via Maillard Reaction: Antioxidant and Techno-Functional Properties
Authors: Mshayisa Vusi Vincent , Van Wyk Jessy
Published: April 2021

The food industry is considering novel sources of proteins with enhanced functionalities to meet the increasing demand and population growth. Edible insect proteins have emerged as an alternative that is environmentally friendly and economically viable and thus could make a significant contribution to global food security. This study was aimed to establish the effect of conjugation via the Maillard reaction on the antioxidant and techno-functional properties of black soldier fly larvae protein concentrate. Reaction mixtures containing black soldier fly larvae protein concentrate and glucose (2 : 1 weight ratio) were wet-heated at 50, 70, and 90°C for 2, 4, 6, 8, and 10 h, respectively, with an initial pH of 9. The results showed that the browning indices of the black soldier fly larvae-glucose (BSFL-Glu) model system increased with an increase in reaction time and temperature, with conjugates formed at 90°C exhibiting the highest browning intensity at 420 nm. At 50°C, the DPPH-RS of the conjugates ranged from 15.47 to 32.37%. The ABTS+ radical scavenging activity of BSFL-Glu conjugates produced at 90°C exhibited significantly (

p
<
0.05

) higher scavenging activity as a function of reaction time. The foaming capacity of BSFL-Glu conjugates produced at 70°C showed a significant increase (

p
<
0.05

) as a function of reaction time. Principal component analysis was applied to browning and antioxidant indices. Component 1 of the score plot accounted for 89%, while component 2 accounted for 8% of the observed variability and allowed discrimination/differentiation of the samples based on the heating temperature. These findings provide a practical means to improve the functionality of novel edible insect proteins for food application.
Efficient Exponential Time-Differencing Methods for the Optical Soliton Solutions to the Space-Time Fractional Coupled Nonlinear Schrödinger Equation
Authors: Liang Xiao , Tang Bo
Published: April 2021

The coupled nonlinear Schrödinger equation is used in simulating the propagation of the optical soliton in a birefringent fiber. Hereditary properties and memory of various materials can be depicted more precisely using the temporal fractional derivatives, and the anomalous dispersion or diffusion effects are better described by the spatial fractional derivatives. In this paper, one-step and two-step exponential time-differencing methods are proposed as time integrators to solve the space-time fractional coupled nonlinear Schrödinger equation numerically to obtain the optical soliton solutions. During this procedure, we take advantage of the global Padé approximation to evaluate the Mittag-Leffler function more efficiently. The approximation error of the Padé approximation is analyzed. A centered difference method is used for the discretization of the space-fractional derivative. Extensive numerical examples are provided to demonstrate the efficiency and effectiveness of the modified exponential time-differencing methods.
An Improved Non-Face-to-Face, Contactless Preference Survey System
Authors: Rim KwangCheol
Published: April 2021

Conventional election-related public opinion polls have utilized the automated response system (ARS) method. The ARS public opinion polls are predicated on the convenience of use and require random telephonic responses. However, the actual response rate is less than 5%. As a result, discrepancies between recent public opinion polls and the actual election results have become an issue. In this study, we propose a system that quantifies the preferences by region, age, and gender by quantifying emotions based on the behaviors and facial expressions of the citizens passing by at the campaign site and utilizes them as basic statistics. Furthermore, a previously published facial recognition artificial intelligence (AI) was used to obtain age, gender, and various facial recognition data, along with citizens’ emotions. The published facial recognition AI produced stability of over 99% recognition rate. The data structure followed a weighted reverse tree structure, and facial expressions, gender, and age were analyzed using the published facial recognition algorithm. Moreover, the expressions as well as the behaviors showing emotions were merged to gather and analyze data with weights.
Strength and Durability Properties of Concrete Containing Pumice and Scoria as Supplementary Cementitious Material
Authors: Chambua Safiel Tumaini , Jande Yusufu Abeid Chande , Machunda Revocatus Lazaro
Published: April 2021

Concrete structures suffer serious deterioration under a corrosive environment. Consequently, the service life of these concrete structures is decreased and deteriorates under combined attack of sulphate and chlorides. Most studies confined on single deteriorating factor such as sulphate attack only or chloride attack only but the current study focused on the influence of natural pumice (NP) and natural scoria (NS) on the strength performance of concrete exposed to the combined attack of sulphate and chloride. Portland cement (PLC) was replaced with NP or NS at a substitution level of 10%. Concrete samples were cured in water for the curing period of 28 days. Afterwards, the specimens were immersed in 5% sodium sulphate (Na2SO4), 5% sodium chloride (NaCl), and combined sodium sulphate and chloride solutions for additional curing of 28, 56, and 90 days. The results were compared between concrete mixes with NP or NS and control mix (CT) with PLC. The effects of sulphate, chloride, and combined sulphate and chloride were evaluated in terms of change in weight, variation in compressive strength, and degree of damage. Conclusively, the application of NP and NS has extraordinary potential to be utilized as a cementitious material in concrete to increase the resistance against aggressive salts.
Impact of Postshock Transcutaneous Pacing on Chest Compression Quality during Resuscitation: A Simulation-Based Pilot Study
Authors: Telec Wojciech , Kłosiewicz Tomasz , Zalewski Radosław , Żukowska-Karolak Julia , Baszko Artur , Puślecki Mateusz
Published: April 2021

Background. Successful defibrillation is commonly followed by a transient nonperfusing state. To provide perfusion in this stagnant phase, chest compressions are recommended irrespective of arrhythmia termination. Implantable cardioverters-defibrillators (ICD) used immediately after delivery of the shock are capable of pacing the heart, and this feature is commonly activated in these devices. Potential utility of external, transcutaneous postshock pacing in patients with SCA in shockable rhythms has not been determined. This study aimed at presenting an impact of a short-term external postshock pacing (ePSP) on a quality of chest compressions (CC) without compromising them. Methods. The study was designed as a high-fidelity simulation study. Twenty triple-paramedic teams were invited. Participants were asked to take part in a 10-minute adult cardiac arrest scenario with ventricular fibrillation. In the first simulation, paramedics had to resume compressions after each shock (control group). In the second, simultaneous with compressions, one of the rescuers started transcutaneous pacing (TCP) with a current output of 200 mA and a pacer rate of 80 ppm. TCP was finished after 30 seconds (experimental group). The primary outcomes were chest compression fraction (CCF), mean depth and rate of compressions, percent of fully recoiled compressions, and percent of compressions of correct depth and their rate. Results. In both experimental and control group, CCF, mean depth, and rate were similar (84.65 ± 3.67 vs. 85.45 ± 4.95,p=0.54; 55.75 ± 3.40 vs. 55.25 ± 2.73,p=0.63; 122.70 ± 4.92 vs. 120.80 ± 6.00,p=0.25, respectively). In turn, percent of CC performed in correct depth, rate, and recoil was unsatisfactory in both groups (51.00 ± 17.40 vs. 52.60 ± 18.72,p=0.76; 122.70 ± 4.92 vs. 120.80 ± 6.00,p=0.25, respectively). Small differences were not statistically significant. Moreover, appropriate hand-positioning was observed more frequently in the control group, and this was the only significant difference (95.60 ± 5.32 vs. 99.30 ± 1.59,p=0.006). Conclusion. This difference was statistically significant (p<0.01). Introducing an ePSP does not influence relevantly the quality of CC.
Kirenol Inhibits B[a]P‐Induced Oxidative Stress and Apoptosis in Endothelial Cells via Modulation of the Nrf2 Signaling Pathway
Authors: Rajendran Peramaiyan , Alzahrani Abdullah M. , Ahmed Emad A. , Veeraraghavan Vishnu Priya
Published: April 2021

Atherosclerosis is a persistent inflammatory disorder specified by the dysfunction of the arteries, the world’s leading cause of cardiovascular diseases. We sought to determine the effectiveness of KRL in B[a]P‐induced oxidative stress and programmed cell death in endothelial cells. Western blotting, real‐time PCR, DCFH2‐DA, and TUNEL staining were performed to detect pPI3K, pAKT, Nrf2, HO‐1, NQO‐1, Bcl2, Bax, and caspase‐3 on the HUVECs. Through the pretreatment of KRL, a drastic enhancement was observed in the cell viability of HUVECs, whereas DNA damage and generation of reactive oxygen species induced by B[a]P was suppressed. KRL’s potential use as an antioxidant was observed to have a direct correlation with an antioxidant gene’s augmented expression and the nuclear translocation activation of Nrf2, even during the event when B[a]P was found to be absent. In addition, this study proved that the signaling cascades of PI3K/AKT mediated Nrf2 translocation. Activation of suppressed nuclear Nrf2 and reduced antioxidant genes across cells interacting with an LY294002 confirmed this phenomenon. In addition, knockdown of Nrf2 by Nrf2‐siRNA transfection abolished the protective effects of KRL on HUVECs cells against oxidative damage. Finally, the expression of apoptotic proteins also supported the hypothesis that KRL may inhibit endothelial dysfunction. This study showed that KRL potentially prevents B[a]P‐induced redox imbalance in the vascular endothelium by inducing the Nrf2 signaling via the PI3K/AKT pathway.
Emergency Resource Location and Allocation in Traffic Contingency Plan for Sports Mega‐Event
Authors: Shen Ling , Lu Jian , Deng Ling , Li Manman
Published: April 2021

In view of the transactional and textual features on issue handling in mega‐event traffic contingency plan, this paper gives a quantitative method for emergency resources location and allocation. Given that the requirement on safeguards in the sports mega‐events is temporary and stringent, we first divide the facilities into temporary emergency facilities and fixed emergency facilities and the resources into material resources and human resources. Considering the uncertainty of emergency incidents, we then construct a mixed integer linear programming model. To solve this model, the bisection method is used to import the material quantity placed in each emergency facility, and the shortest path algorithm is used to import the rescue time matrix. Considering the slowness of convergence rate when the road network is large, a modified matrix real‐coded genetic algorithm is designed with the crossover operator based on a greedy algorithm. The application of the model and algorithms is validated by the case based on 2022 Beijing Winter Olympics. Sensitivity analysis of some important parameters is also conducted to provide insights for traffic emergency resources management in sports mega‐event.
Surgical Healthcare Workers Knowledge and Attitude on Infection Prevention and Control: A Case of Tamale Teaching Hospital, Ghana
Authors: Alhassan Abdul Rauf , Kuugbee E. D. , Der E. M.
Published: April 2021

Background. Most morbidities and mortalities related to clinical, diagnostic, and therapeutic procedures are related to infection and the solution to this is good infection prevention and control (IPC) compliance which is influenced by the right knowledge and positive attitude. Aim. This study aimed to assess infection prevention and control (IPC) knowledge and attitude among healthcare workers at the surgical department of Tamale Teaching Hospital (TTH). Methods. This study was conducted using a descriptive cross-sectional survey. Data entry and analysis were done using Statistical Package for the Social Sciences (SPSS) version 20 and Graph Pad Prism version 6.05. Tables, frequencies, and percentages were used for descriptive analysis and chi-square analysis for the associations. Results. Of the 156 participants who responded, 22 (14.1%) were doctors, with 107 (68.6%) nurses, 12 (7.7%) certified registered anesthetics (CRA), and 15 (9.6%) orderlies. Approximately, 50.6% of the respondents were knowledgeable with regard to IPC and 55.1% of the respondents had a good attitude towards IPC. Factors associated with knowledge level were educational level

p
≤
0.001

, occupation

p
≤
0.001

, marital status

p
=
0.030

, and age

p
=
0.030

. The occupation was the only factor associated with the attitude level

p
=
0.048

. Conclusion. More than half of the healthcare providers reported good knowledge and attitude towards IPC. Proportionally, more nurses had good IPC knowledge and attitude as compared to other professional groups. Firming up and assimilating universal precaution with routine services by providing training, protocol, rules, and regulation are recommended.
Investigation on Parameter Calibration Method and Mechanical Properties of Root-Reinforced Soil by DEM
Authors: Bai Hao , Li Ruidong , Wang Wubin , Xie Kang , Wang Xiang
Published: April 2021

The behavior of root-soil system has raised more and more attention in both ecological and geotechnical fields. In this study, a two-dimensional discrete element method is employed using PFC2D to simulate the root-reinforced soil. The root system is mimicked by chains of bonded discs, while the soil is modeled by granular particles. The tensile strength of the root is modeled by interdiscs’ bonding strength. Three laboratory tests were studied to calibrate the micromechanical parameters of DEM. Finally, direct shear tests on rooted soil are simulated to investigate the influence of different root characteristics on the root reinforcement effect.
Metabolomics Analysis of the Development of Sepsis and Potential Biomarkers of Sepsis‐Induced Acute Kidney Injury
Authors: Ping Feng , Li Yingchuan , Cao Yongmei , Shang Jiawei , Zhang Zhongwei , Yuan Ziming , Wang Wei , Guo Yong
Published: April 2021

Sepsis‐induced acute kidney injury (SI‐AKI) is a serious condition in critically ill patients. Currently, the diagnosis is based on either elevated serum creatinine levels or oliguria, which partially contribute to delayed recognition of AKI. Metabolomics is a potential approach for identifying small molecule biomarkers of kidney diseases. Here, we studied serum metabolomics alterations in rats with sepsis to identify early biomarkers of sepsis and SI‐AKI. A rat model of SI‐AKI was established by intraperitoneal injection of lipopolysaccharide (LPS). Thirty Sprague‐Dawley (SD) rats were randomly divided into the control (CT) group and groups treated for 2 hours (LPS2) and 6 hours (LPS6) with LPS (10 rats per group). Nontargeted metabolomics screening was performed on the serum samples from the control and SI‐AKI groups. Combined multivariate and univariate analysis was used for pairwise comparison of all groups to identify significantly altered serum metabolite levels in early‐stage AKI in rats with sepsis. Orthogonal partial least squares discriminant analysis (OPLS‐DA) showed obvious separation between the CT and LPS2 groups, CT and LPS6 groups, and LPS2 and LPS6 groups. All comparisons of the groups identified a series of differential metabolites according to the threshold defined for potential biomarkers. Intersections and summaries of these differential metabolites were used for pathway enrichment analysis. The results suggested that sepsis can cause an increase in systemic aerobic and anaerobic metabolism, an impairment of the oxygen supply, and uptake and abnormal fatty acid metabolism. Changes in the levels of malic acid, methionine sulfoxide, and petroselinic acid were consistently measured during the progression of sepsis. The development of sepsis was accompanied by the development of AKI, and these metabolic disorders are directly or indirectly related to the development of SI‐AKI.
Multitier Service Migration Framework Based on Mobility Prediction in Mobile Edge Computing
Authors: Yang Run , He Hui , Zhang Weizhe
Published: April 2021

Mobile edge computing (MEC) pushes computing resources to the edge of the network and distributes them at the edge of the mobile network. Offloading computing tasks to the edge instead of the cloud can reduce computing latency and backhaul load simultaneously. However, new challenges incurred by user mobility and limited coverage of MEC server service arise. Services should be dynamically migrated between multiple MEC servers to maintain service performance due to user movement. Tackling this problem is nontrivial because it is arduous to predict user movement, and service migration will generate service interruptions and redundant network traffic. Service interruption time must be minimized, and redundant network traffic should be reduced to ensure service quality. In this paper, the container live migration technology based on prediction is studied, and an online prediction method based on map data that does not rely on prior knowledge such as user trajectories is proposed to address this challenge in terms of mobility prediction accuracy. A multitier framework and scheduling algorithm are designed to select MEC servers according to moving speeds of users and latency requirements of offloading tasks to reduce redundant network traffic. Based on the map of Beijing, extensive experiments are conducted using simulation platforms and real‐world data trace. Experimental results show that our online prediction methods perform better than the common strategy. Our system reduces network traffic by 65% while meeting task delay requirements. Moreover, it can flexibly respond to changes in the user’s moving speed and environment to ensure the stability of offload service.
The Study for Synchronization between Two Coupled FitzHugh-Nagumo Neurons Based on the Laplace Transform and the Adomian Decomposition Method
Authors: Zhen Bin , Song Zigen
Published: April 2021

The synchronization between two coupled FitzHugh-Nagumo (FHN) neurons with or without external current is studied by using the Laplace transform and the Adomian decomposition method. Different from other researches, the synchronization error system is expressed as sets of Volterra integral equations based on the convolution theorem in the Laplace transform. Then, it is easy to analytically obtain the conditions that synchronization errors disappear based on the successive approximation method in integral equation theorem, the correctness of which is verified by numerical simulations. Furthermore, the synchronous dynamics of the two coupled FHN neurons also can be written in the form of Volterra integral equations, which is more convenient to analytically solve by using the Adomian decomposition method. It is found that the occurrence of synchronization between the two FHN neurons only depends on the coupling strength and is irrelevant to the external current. Only synchronous rest state in the two FHN neurons without external current can be achieved, while synchronous spikes appear if the external current is not zero.
Ugni molinae Fruit as a Source of Bioactive Compounds with Good Quality Traits
Authors: Castro Ricardo I. , Ramos Patricio , Parra-Palma Carolina , Morales-Quintana Luis
Published: April 2021

Since the intake of fruits and vegetables displays important effects on the incidence of several chronic diseases in humans, consumers’ attention worldwide is focused on the identification of functional foods. In this sense, Ugni molinae (murtilla or murta fruit) is an important source of molecules with a strong antioxidant capacity that is widely used as a medicinal plant in Southern Argentina‐Chile. Research on murtilla berries showed that this fruit and its leaves can be an excellent source of polyphenols and bioactive compounds with antibacterial and antioxidant capacity. This review is aimed at providing valuable information and discussing the available literature focused on four principal points: (i) fruit quality and plant physiology, (ii) compound content with bioactive properties, (iii) health properties for consumers of the fruit and leaves, and (iv) challenges for future research. Based on these four points, we propose that murtilla fruit can be a potential ingredient for new functional food products.
Bone Mesenchymal Stem Cells Contribute to Ligament Regeneration and Graft–Bone Healing after Anterior Cruciate Ligament Reconstruction with Silk–Collagen Scaffold
Authors: Bi Fanggang , Chen Yangdi , Liu Junqi , Hu Wenhao , Tian Ke
Published: April 2021

Anterior cruciate ligament (ACL) reconstruction was realized using a combination of bone mesenchymal stem cells (BMSCs) and silk–collagen scaffold, and an in vivo evaluation of this combination was performed. By combining type I collagen and degummed silk fibroin mesh, silk–collagen scaffolds were prepared to simulate ligament components. BMSCs isolated from bone marrow of rabbits were cultured for a homogenous population and seeded on the silk–collagen scaffold. In the scaffold and BMSC (S/C) group, scaffolds were seeded with BMSCs for 72 h and then rolled and used to replace the ACL in 20 rabbits. In the scaffold (S) group, scaffolds immersed only in culture medium for 72 h were used for ACL reconstruction. Specimens were collected at 4 and 16 weeks postoperatively to assess ligament regeneration and bone integration. HE and immunohistochemical staining (IHC) were performed to assess ligament regeneration in the knee cavity. To assess bone integration at the graft–bone interface, HE, Russell–Movat staining, micro-CT, and biomechanical tests were performed. After 4 weeks, vigorous cell proliferation was observed in the core part of the scaffold in the S/C group, and a quantity of fibroblast-like cells and extracellular matrix (ECM) was observed in the center part of the graft at 16 weeks after surgery. At 4 and 16 weeks postoperatively, the tenascin-C expression in the S/C group was considerably higher than that in the S group (4 w,

p
<
0.01

; 16 w,

p
<
0.01

). Furthermore, bone integration was better in the S/C group than in the S group, with histological observation of trabecular bone growth into the graft and more mineralized tissue formation detected by micro-CT (4 w, bone volume fraction (BV/TV),

p
=
0.0169

, bone mineral density (BMD),

p
=
0.0001

; 16 w, BV/TV,

p
=
0.1233

, BMD,

p
=
0.0494

). These results indicate that BMSCs promote ligament regeneration in the knee cavity and bone integration at the graft–bone interface. Silk–collagen scaffolds and BMSCs will likely be combined for clinical practice in the future.
Humoral Acute Rejection in a Kidney Transplant Recipient with Idiopathic Thrombocytopenic Purpura
Authors: Rico-Portillo Ana Paola , Cerrillos-Gutierrez José Ignacio , Andrade-Sierra Jorge , Gutiérrez-Govea Alfredo , Rojas-Campos Enrique , Mendoza-Cerpa Claudia Alejandra , Gómez-Navarro Benjamín
Published: April 2021

A 47-year-old male was diagnosed with chronic kidney disease (CKD) in 2011; idiopathic thrombocytopenic purpura (ITP) was also diagnosed in 2011 refractory to medical treatment and finally treated with splenectomy (2017) without relapses since that date, 5 blood transfusions, and 4 platelet apheresis in 2017. Renal transplant from a living related donor (brother), ABO compatible, crossmatch were negative, sharing 1 haplotype. Donor-specific anti-HLA antibody was negative. Graft function was stable until the 5th day and graft biopsy on the 6th day; thrombotic microangiopathy (TMA), C4D negative and inflammatory infiltration of polymorphonuclear leukocytes inside peritubular capillary, and anti-MICA antibodies were positive. The treatment used were plasmapheresis, intravenous immunoglobulin, and rituximab. Serum creatinine began to decrease since the 14th day, and by day 33, post-RT graft function was restored.
A New Result of Stability for Thermoelastic-Bresse System of Second Sound Related with Forcing, Delay, and Past History Terms
Authors: Ouchenane Djamel , Khalili Zineb , Yazid Fares , Abdalla Mohamed , Cherif Bahri Belkacem , Mekawy Ibrahim
Published: April 2021

We consider a one-dimensional linear thermoelastic Bresse system with delay term, forcing, and infinity history acting on the shear angle displacement. Under an appropriate assumption between the weight of the delay and the weight of the damping, we prove the well-posedness of the problem using the semigroup method, where an asymptotic stability result of global solution is obtained.