bluuebunny/crossref_metadata_2025 huggingface dataset:
Drug-Coated Balloon versus Drug-Eluting Stent in Patients with Small-Vessel Coronary Artery Disease: A Meta-Analysis of Randomized Controlled Trials
Authors: Wu Xinying , Li Lun , He Li
Published: April 2021

Background. Percutaneous coronary intervention (PCI) with drug-eluting stents (DES) of small-vessel coronary artery disease (SVD) is related to an increased risk of in-stent restenosis (ISR) and stent thrombosis (ST). The application of the drug-coated balloon (DCB) for patients with SVD remains controversial. Objectives. Assess the outcomes of DCB in the treatment of SVD compared with DES in patients with SVD. Methods. A meta-analysis of randomized controlled trials (RCTs) published up to June 2020, reporting the outcomes of DCB versus DES in the treatment of SVD, was performed. Results. Four RCTs with 1227 patients were included. The results indicated that DCB was associated with the decreased risk for myocardial infarction (MI) compared with the DES, but the difference showed no significance (OR 0.50, 95% CI 0.24–1.03,

P
=
0.06

). And, there was no significant difference in death (OR 0.76, 95% CI 0.17–3.43,

P
=
0.72

), cardiac death (OR 1.92, 95% CI 0.74–4.98,

P
=
0.18

), target vessel revascularization (TVR) (OR 0.81, 95% CI 0.51–1.28,

P
=
0.36

), target lesion revascularization (TLR) (OR 1.29, 95% CI 0.66–2.52,

P
=
0.46

), and major adverse cardiac events (MACE) (OR 0.92, 95% CI 0.61–1.38,

P
=
0.69

) between the DCB group and DES group. Conclusion. Compared with DES, DCB was associated with a decreased risk of MI among patients with SVD, but the difference showed no significance. The application of DCB in SVD is associated with comparable outcomes of death, TVR, and MACE when compared with DES.
Dirac Equation on the Kerr–Newman Spacetime and Heun Functions
Authors: Dariescu Ciprian , Dariescu Marina-Aura , Stelea Cristian
Published: April 2021

By employing a pseudoorthonormal coordinate-free approach, the Dirac equation for particles in the Kerr–Newman spacetime is separated into its radial and angular parts. In the massless case to which a special attention is given, the general Heun-type equations turn into their confluent form. We show how one recovers some results previously obtained in literature, by other means.
Recent Progress about Flight Delay under Complex Network
Authors: Zhixing Tang , Shan Huang , Songchen Han
Published: April 2021

Flight delay is one of the most challenging threats to operation of air transportation network system. Complex network was introduced into research studies on flight delays due to its low complexity, high flexibility in model building, and accurate explanation about real world. We surveyed recent progress about flight delay which makes extensive use of complex network theory in this paper. We scanned analyses on static network and temporal evolution, together with identification about topologically important nodes/edges. And, we made a clarification about relations among robustness, vulnerability, and resilience in air transportation networks. Then, we investigated studies on causal relations, propagation modellings, and best spreaders identifications in flight delay. Ultimately, future improvements are summarized in fourfold. (1) Under Complex Network, flight operation relevant subsystems or sublayers are discarded by the majority of available network models. Hierarchical modelling approaches may be able to improve this and provide more capable network models for flight delay. (2) Traffic information is the key to narrow the gap between topology and functionality in current situations. Flight schedule and flight plan could be employed to detect flight delay causalities and model flight delay propagations more accurately. Real flight data may be utilized to validate and revise the detection and prediction models. (3) It is of great importance to explore how to predict flight delay propagations and identify best spreaders at a low cost of calculation complexity. This may be achieved by analyzing flight delay in frequency domain instead of time domain. (4) Summation of most critical nodes/edges may not be the most crucial group to network resilience or flight delay propagations. Effective algorithm for most influential sequence is to be developed.
Interleukin‐27 as a Diagnostic Biomarker for Patients with Sepsis: A Meta‐Analysis
Authors: Wang Ying , Zhao Jingyi , Yao Yinhui , Zhao Dan , Liu Shiquan
Published: April 2021

Background. The present study was aimed to investigate the value of blood interleukin‐27 (IL‐27) as a diagnostic biomarker of sepsis. Methods. We searched PubMed, EMBASE, the Cochrane Library, and the reference lists of relevant articles. All studies published up to October 21, 2020, which evaluated the accuracy of IL‐27 levels for the diagnosis of sepsis were included. All the selected papers were assessed using the Quality Assessment of Diagnostic Accuracy Studies‐2 (QUADAS‐2). We used a bivariate random effects model to estimate sensitivity, specificity, diagnostic odds ratios (DOR), and a summary receiver operating characteristic curve (SROC). Deeks’ funnel plot was used to illustrate the potential presence of publication bias. Results. This meta‐analysis included seven articles. The pooled sensitivity, specificity, and DOR were 0.85 (95% CI, 0.72‐0.93), 0.72 (95% CI, 0.42‐0.90), and 15 (95% CI, 3‐72), respectively. The area under the summary receiver operating characteristic curve was 0.88 (95% CI, 0.84‐0.90). The pooled I2 statistic was 96.05 for the sensitivity and 96.65 for the specificity in the heterogeneity analysis. Deeks’ funnel plot indicated no publication bias in this meta‐analysis (P = 0.07). Conclusions. The present results showed that IL‐27 is a reliable diagnostic biomarker of sepsis, but it should be investigated in combination with other clinical tests and results.
[Retracted] Flat Panel CT Scanning Is Helpful in Predicting Hemorrhagic Transformation in Acute Ischemic Stroke Patients Undergoing Endovascular Thrombectomy
Authors: Chen Liuwei , Xu Yi , Shen Rui , Sun Jiping , Zhang Xiang , Zhang Quanbin , Wang Feng
Published: April 2021

Purpose. Hyperdense lesions are frequently revealed on flat panel CT (FP‐CT) immediately after endovascular thrombectomy in patients with acute ischemic stroke. This study is aimed at discriminating hyperdense lesions caused by extravasation plus hemorrhage from those caused by contrast extravasation alone. Methods. We retrospectively analyzed clinical and radiological data of patients who underwent an immediate postprocedure FP‐CT scan and a follow‐up noncontrast CT 24 hours after thrombectomy. We especially focused on the Maximum Hounsfield Units (HUmax) of each hyperdense lesion. A hyperdense lesion was judged to be hemorrhagic when it persisted on noncontrast CT and/or developed a mass effect. Results. Of 81 patients included in this study, 32 (39.5%) patients presented 41 hyperdense lesions on FP‐CT. The chance of hemorrhagic transformation is higher in patients with hyperdense lesions on FP‐CT than that in patients without hyperdense lesions (23/32 vs. 1/49, p < 0.001). The HUmax of hyperdensity on FP‐CT can predict hemorrhagic transformation with an area under the curve of 0.805 (95% CI: 0.67‐0.94, p = 0.02). The sensitivity, specificity, positive, and negative predictive values of hyperdensity on FP‐CT for hemorrhagic transformation were 96%, 84%, 72%, and 98%, respectively. A HUmax of >600 predicted hemorrhagic transformation with a sensitivity of 50% and a specificity of 100%. Conclusions. The presence of hyperdensity on FP‐CT can predict hemorrhagic transformation with a high sensitivity and negative predictive value. The measurement of HUmax of hyperdense lesion on FP‐CT can be applied to the management of patients undergoing endovascular recanalization.
Difference Analysis of Disaster Types and Grading Control Technologies for Risk of Caving of Coal Roadway Roof
Authors: Feng Jicheng , Cheng Zhiheng , Wang Hongbing , Shi Jianjun , Shi Haoyu , Yin Shuaifeng
Published: April 2021

In view of the problem of a caving roof along different parts of the same roadway in a mine, this study classifies the mechanical characteristics of the local instability of the roof based on differences in the rock mass media and types of damage. We determine the factors influencing the quantitative relationship between the failure height of the roof and the environment to establish an indicator system for classifying the grades of risk of the roof caving. This is used to predict the height at which the roof caves along the roadway in a coal seam through fuzzy variable weighting analysis. We also develop software for the grading system of risks of caving of the roof and draw a grading map to represent this risk for a roadway in coal seam No. III in Zhaogu Coal Mine No. 2 in Jiaozuo City of Henan Province, China. According to the zoning characteristics of the coal mine, a targeted support design test is carried out in the same intake airway of working face 11030 of the mine. The results show that the proposed classification method conforms to safe practices in underground mining. The stability of the roadway during service and the grades determined using the proposed method were consistent. This has important theoretical significance and practical value for designing support for roadways and timely reinforcements in areas with a high‐risk grade to guarantee the safe operation of coal mines.
FPGA Realization of Spherical Chaotic System with Application in Image Transmission
Authors: Nuñez-Perez Jose Cruz , Adeyemi Vincent Ademola , Sandoval-Ibarra Yuma , Pérez-Pinal F. Javier , Tlelo-Cuautle Esteban
Published: April 2021

This paper considers a three-dimensional nonlinear dynamical system capable of generating spherical attractors. The main activity is the realization of a spherical chaotic attractor on Intel and Xilinx FPGA boards, with a focus on implementation of a secure communication system. The first major contribution is the successful synchronization of two chaotic spherical systems, in VHDL program, in a master-slave topology using Hamiltonian forms. The synchronization errors show that the two spherical chaotic systems synchronize in a very short time after which the error signals become zero. The second major contribution is the FPGA realization of a spherical chaotic attractor-based secure communication system, which involves encrypting both grayscale and RGB images with chaos and diffusion key at the transmitting system, sending the encrypted image via the state variables, and reconstructing the encrypted image at the receiving system. The Intel Stratix III and Xilinx Artix-7 AC701 results are the same as those of MATLAB. The statistical analyses of the encrypted and received images show that the implemented system is very effective, as it reveals high degree of randomness in the encrypted images with the entropy test, and the obtained correlation coefficient, which is zero, removes relativity between the original and encrypted images. Finally, the transmission system fully recovers the original grayscale and RGB images without loss of information.
Almost Periodic Functions and Their Applications: A Survey of Results and Perspectives
Authors: Du Wei-Shih , Kostić Marko , Pinto Manuel
Published: April 2021

The main aim of this survey article is to present several known results about vector-valued almost periodic functions and their applications. We separately consider almost periodic functions depending on one real variable and almost periodic functions depending on two or more real variables. We address several open problems and possibilities for further investigations of almost periodic functions, quoting more than two hundred references about the subject under our consideration.
Using the Mathematical Model on Precision Marketing with Online Transaction Data Computing
Authors: Wu Jun , Shi Li , Xu Guangshu , Yuan Yu-Hsi , Tsai Sang-Bing , Hao Weiyi , Jiang Jiesong
Published: April 2021

In this paper, a decision-making system for precision marketing is presented to deal with real-world problems based on real e-business data collected in a company in Beijing. During the data preprocessing, the authors conducted a cleaning course to make sure the data to be analyzed in the latter part of the paper were credential. Based on the processed data, the authors analyzed consumer purchasing behaviors using three classic recommendation algorithms and made a performance comparison of the three algorithms. At the end of this paper, the authors proposed a series of precision marketing strategies which had been adopted by the data source company and had been proved to be effective in improving the performance.
“Primary Hyperparathyroidism (PHPT) in Children: Two Case Reports and Review of the Literature”
Authors: Tuli Gerdi , Munarin Jessica , Tessaris Daniele , Buganza Raffaele , Matarazzo Patrizia , De Sanctis Luisa
Published: April 2021

Primary hyperparathyroidism (PHPT) is a rare disorder in children and adolescents. Typical biochemical features are hypercalcemia and hypophosphatemia, but the clinical features can be heterogeneous, and in some cases, symptoms are vague and nonspecific, leading to misdiagnosis or late diagnosis. Herein, we report two cases of PHPT in pediatric age with different presenting symptoms, pain in the foot, and progressive alteration of the gait in the first case and recurrent abdominal pain with emotional lability in the second. Biochemical and radiological assessment confirmed PHPT. Both cases were treated surgically as definitive treatment, but in the second case, previous medical treatment with cinacalcet, a calcimimetic agent, was required to reduce serum PTH and calcium levels. After surgery, despite conventional treatment with calcium and calcitriol, case 1 developed a hungry bone syndrome. The analysis of the MEN-1 (Multiple Endocrine Neoplasia) gene was negative in both cases. A diagnosis of PHPT should be considered when children or adolescents present bone pain with radiological imaging of osteolytic lesion and biochemical feature of hypercalcemia associated with hypophosphatemia. In PHPT, the gold standard treatment is represented by surgery followed by strict postoperative endocrine monitoring to maintain adequate homeostasis of calcium and bone metabolism.
Research on Human Motion Recognition Based on Data Redundancy Technology
Authors: Yang Hong-Lan , Huang Meng-Zhe , Cai Zheng-Qun
Published: April 2021

Aiming at the problems of low recognition rate and slow recognition speed of traditional body action recognition methods, a human action recognition method based on data deduplication technology is proposed. Firstly, the data redundancy technology and perceptual hashing technology are combined to form an index, and the image is filtered from the structure, color, and texture features of human action image to achieve image redundancy processing. Then, the depth feature of processed image is extracted by depth motion map; finally, feature recognition is carried out by convolution neural network so as to achieve the purpose of human action recognition. The simulation results show that the proposed method can obtain the optimal recognition results and has strong robustness. At the same time, it also fully proves the importance of human motion recognition.
More on Selective Covering Properties in Bitopological Spaces
Authors: Kočinac Ljubiša D. R. , Özçağ Selma
Published: April 2021

In this study, we continue our investigation of selective covering properties in bitopological spaces. We discuss their behaviour under certain kinds of mappings. We also introduce selective versions of the ccc property and the star-ccc property in bitopological spaces and give few of their relations with other selective properties. Also, we consider preservation of selective covering properties of bitopological spaces under some known relations in bitopological context.
Ink Art Three‐Dimensional Big Data Three‐Dimensional Display Index Prediction Model
Authors: Cao Xiaonan
Published: April 2021

This paper starts with the study of realistic three‐dimensional models, from the two aspects of ink art style simulation model and three‐dimensional display technology, explores the three‐dimensional display model of three‐dimensional model ink style, and conducts experiments through the software development platform and auxiliary software. The feasibility of the model is verified. Aiming at the problem of real‐time rendering of large‐scale 3D scenes in the model, efficient visibility rejection method and a multiresolution fast rendering method were designed to realize the rapid construction and rendering of ink art 3D virtual reality scenes in a big data environment. A two‐dimensional cellular automaton is used to simulate a brushstroke model with ink and wash style, and outlines are drawn along the path of the brushstroke to obtain an effect close to the artistic style of ink and wash painting. Set the surface of the model with ink style brushstroke texture patterns, refer to the depth map, normal map, and curvature map information of the model, and simulate the drawing effect of the method by procedural texture mapping. Example verification shows that the rapid visualization analysis model of ink art big data designed in this paper is in line with the prediction requirements of ink art big data three‐dimensional display indicators. The fast visibility removal method is used to deal with large‐scale three‐dimensional ink art in a big data environment. High efficiency is achieved in virtual reality scenes, and the multiresolution fast rendering method better maintains the appearance of the prediction model without major deformation.
Research on Bearing Characteristics of Open‐Ended Pipe Piles under Static Load
Authors: Feng Haibao , Dai Xingke , Chen Shuiyue , Chen Jianwei
Published: April 2021

The accurate estimate of the ultimate bearing capacity of a single pile in the vertical direction is an important issue in the design of the pile foundation. This paper presents a static test on a single‐pile model. The test was performed through a large‐scale model casing test equipment that is independently developed. Various factors that affect the different test soil samples have been taken into account. In addition, the test has measured the pile’s internal stress and displacement through the sensors that were installed on the pile. What is more, a series of studies on the settling character of the single pile, pile lateral friction, changing nature of tip resistance, and its development with settling have been carried out. Finally, this paper analyzes the bearing capacity behavior and load transfer mechanism in the compressive static load test on the single pile in the vertical direction. The test results show that, under the same static load, the lateral friction of a pile in the sand is bigger than that in the silty clay, and with the increasing load at the pile tip, the increment speed of tip resistance in the silty clay is much faster than that in the sand, while pile’s bearing capacity in the sand is much bigger than that in the silty clay.
Antioxidant Responses in Hypertensive Postmenopausal Women after Acute Beetroot Juice Ingestion and Aerobic Exercise: Double Blind and Placebo‐Controlled Crossover Trial
Authors: Amaral Ana Luiza , Mariano Igor Moraes , Carrijo Victor Hugo V. , de Souza Tállita Cristina F. , de Souza Adriele V. , Caixeta Douglas C. , Teixeira Renata R. , de Oliveira Erick P. , Espindola Foued S. , Puga Guilherme Morais
Published: April 2021

This study is aimed to analyze the effect of different nitrate concentrations [NO3-] present in beetroot juice (BJ) on salivary oxidative stress markers after acute exercise performance in hypertensive postmenopausal women. Thirteen hypertensive postmenopausal women participated in three experimental sessions, taking different beverages: noncaloric orange flavored drink (OFD), low nitrate (low‐NO3-) BJ, and high nitrate (high‐NO3-) BJ. The participants performed aerobic exercise on a treadmill, at 65–70% of heart rate reserve (HRR), for 40 min. Saliva samples were collected after an overnight fast, 10 minutes before BJ ingestion at 7 : 20 am (0 ′), 120 minutes after beverages ingestion (130 ′), immediately after exercise (170 ′), and 90 min after exercise (260 ′). Salivary total protein (TP), catalase activity (CAT), reduced glutathione (GSH), and total antioxidant capacity by ferric‐reducing antioxidant power (FRAP) concentrations were analyzed. No interaction (session∗time) was found among three sessions over time. Catalase area under the curve (AUC) was lower after both low‐NO3- and high‐NO3- consumption (p < 0.001), and GSH AUC was lower after high‐NO3- (p < 0.001) compared with OFD. So, the acute intake of BJ with aerobic exercise seems to decrease catalase (in high‐NO3- and low‐NO3-) and GSH (in high‐NO3-), besides not interfering with FRAP in hypertensive postmenopausal women.
Effect of Sand Compaction Piles on the Swelling and Shrinkage Behavior of Expansive Soil
Authors: Hussein Mohamed M. A.
Published: April 2021

This study aims to investigate the effect of sand compaction piles on the swelling and shrinkage behavior of expansive clay soil. A series of experimental laboratory tests were carried out using the modified Proctor mold and a circular footing. The diameter of the sand compaction pile was selected to give a replacement area ratio equal to 57%. To model the swelling and shrinkage cycles, water was added to the sample and the heave was recorded at regular time intervals. The shrinkage was obtained by heating the outer surface of the modified Proctor mold at a temperature of 110°C ± 5°C by a development heating system designed for this purpose to accelerate the shrinkage process. The vertical movement was recorded at regular time intervals. The swelling and shrinkage cycles were carried out under an externally applied pressure equal to 120 kPa. The main results of this study showed that, for untreated expansive soil, the swelling potential reaches the highest value at the second cycle and started to decrease for the subsequent cycles. After the fourth cycle, the swelling potential decreases and reaches about half the value of the initial swelling potential and the equilibrium state occurs. For expansive soil treated with a sand compaction pile, it is found that there is a significant reduction in both swelling and shrinkage potential. Moreover, it is observed that after the first cycle both the swelling and shrinkage potential decrease significantly, and both reach a negligible value after the second cycle.
Physical Education Teaching in Colleges and Universities Assisted by Virtual Reality Technology Based on Artificial Intelligence
Authors: Wang Yuqing
Published: April 2021

Virtual reality technology has promoted the reform of education. This research mainly discusses college physical education teaching assisted by artificial intelligence-based virtual reality technology. According to the position change of the virtual human’s center of gravity, the spline keyframe interpolation method is used for interpolation, and the model pose obtained in each frame is rendered to obtain the virtual human’s animation. After synthesizing a virtual human animation with three-dimensional human motion data, the animation can have functions such as video storage, fast playback, slow playback, and freeze. At the same time, the system can also display and play the virtual human animation and the video shot by the camera on the same screen, in order to make an intuitive comparison of the athletes’ movements. Coaches can edit by hand or shoot the sports of outstanding domestic and foreign athletes on the spot and then use VC++6.0 as a development tool to analyze and get the simulation video of the 3D virtual human body. The virtual human animation technology in the motion analysis system is to relocate the three-dimensional motion data extracted from the video captured by the camera to the three-dimensional virtual human model we have established, and the three-dimensional virtual human will then simulate the technical actions of the athletes, which indirectly reflects that the three-dimensional movement information of the athletes enables coaches and athletes to observe the athletes’ technical movements in a three-dimensional space in real time, repeatedly, and from multiple angles so that the coach can accurately guide the athletes’ technical movements. Finally, a neural network based on artificial intelligence technology is used to evaluate the teaching effect. In the comparative experiment, 35% of the people in the virtual teaching experiment group were excellent, while the control group had only 10% in this excellent range (90–100). This research contributes to the smooth progress of VR technology teaching in colleges and universities.
On Some Classes with Norms of Meromorphic Function Spaces Defined by General Spherical Derivatives
Authors: El-Sayed Ahmed A. , Ahmed S. Attia
Published: April 2021

The main concerned target of this article is to define and study some concerned classes of meromorphic function spaces using the general spherical derivatives. The general Besov-type classes of meromorphic functions as well as the general normal functions are considered intensively and both are compared deeply with each other. Specifically, multiple results concerning general meromorphic-type classes as well as non-normal classes are obtained by the help of general spherical derivatives. The concerned results are proved by constructing some specific mild conditions on the sequences of points belonging to the concerned meromorphic-type classes. The obtained results generalize and improve the corresponding previous results in some concerned respects. The concerned proofs and methods are simply presented.
Short-Term Load Forecasting Using Neural Network and Particle Swarm Optimization (PSO) Algorithm
Authors: Shafiei Chafi Zahra , Afrakhte Hossein
Published: April 2021

Electrical load forecasting plays a key role in power system planning and operation procedures. So far, a variety of techniques have been employed for electrical load forecasting. Meanwhile, neural-network-based methods led to fewer prediction errors due to their ability to adapt properly to the consuming load's hidden characteristic. Therefore, these methods were widely accepted by the researchers. As the parameters of the neural network have a significant impact on its performance, in this paper, a short-term electrical load forecasting method using neural network and particle swarm optimization (PSO) algorithm is proposed, in which some neural network parameters including learning rate and number of hidden layers are determined in order to forecast electrical load using the PSO algorithm precisely. Then, the neural network with these optimized parameters is used to predict the short-term electrical load. In this method, a three-layer feedforward neural network trained by backpropagation algorithm is used beside an improved gbest PSO algorithm. Also, the neural network prediction error is defined as the PSO algorithm cost function. The proposed approach has been tested on the Iranian power grid using MATLAB software. The average of three indices beside graphical results has been considered to evaluate the performance of the proposed method. The simulation results reflect the capabilities of the proposed method in accurately predicting the electrical load.
Bearing Fault Diagnosis in the Mixed Domain Based on Crossover‐Mutation Chaotic Particle Swarm
Authors: Xu Tongle , Ji Junqing , Kong Xiaojia , Zou Fanghao , Wang Wilson
Published: April 2021

The classification frameworks for fault diagnosis of rolling element bearings in rotating machinery are mostly based on analysis in a single time‐frequency domain, where sensitive features are not completely extracted. To solve this problem, a new fault diagnosis technique is proposed in the mixed domain, based on the crossover‐mutation chaotic particle swarm optimization support vector machine. Firstly, fault features are generated using techniques in the time domain, the frequency domain, and the time‐frequency domain. Secondly, the weighted maximum relevance minimum redundancy (WMRMR) algorithm is adopted to reduce the dimension of the feature set and to establish the representative feature set. Thirdly, a new crossover‐mutation strategy is suggested to reduce the local minima in optimization, and an optimization disturbance is added. Finally, the support vector machine is optimized using the improved chaotic particle swarm to improve fault classification diagnosis. The effectiveness of the proposed new bearing fault diagnostic technique is verified by experimental tests under different bearing conditions. Test results showed that the bearing fault classification accuracy of CMCPSO‐SVM in the mixed domain was much higher than those in a single feature domain.
The Influence of Fracture Strain Energy on the Burst Tendency of Coal Seams and Field Application
Authors: Guo Hongjun , Ji Ming , Liu Dapeng , Liu Mengxi , Zhao Weisheng
Published: April 2021

Coal is typically considered a special engineering rock mass because of its low strength, high internal fracture development, good permeability, and random distribution of microparticles and fractures. The results of cyclic loading and unloading tests indicate that the strain energy during the coal deformation process can be divided into three parts: plastic strain energy; fracture strain energy; and base‐material strain energy. The energy composition ratio differs depending on coal strength. Lower proportions of fracture strain energy are associated with higher elastic energy indexes, and there is a negative correlation between fracture strain energy and other coal burst tendency indexes. The results were applied on the 4206 isolated island working face of coal mine A in Yan’an, Shanxi, China, yielding good benefits. The findings presented here provide a theoretical basis for understanding the principle of coal seam bursting and guidance for reducing burst risks.
SETUCOM: Secure and Trustworthy Context Management for Context-Aware Security and Privacy in the Internet of Things
Authors: Sylla Tidiane , Chalouf Mohamed Aymen , Krief Francine , Samaké Karim
Published: April 2021

IoT technologies facilitate the development and the improvement of pervasive computing by enabling effective context-awareness features. These features enable the IoT applications to detect the user’s situation and adapt their behavior. They also enable context-aware security and privacy, which consist in adapting security and privacy mechanisms’ deployment to the user’s situation. Research studies on context-aware security and privacy focus on security and privacy mechanisms’ implementation but do not consider the secure and trustworthy context management. In this paper, we introduce a new secure and trustworthy context management system for context-aware security and privacy in the smart city: “SETUCOM.” SETUCOM is the implementation of the DTM (Device Trust Management) module of the CASPaaS (Context-Aware Security and Privacy as a Service) architecture. It secures context information exchange by using a lightweight hybrid encryption system adapted to IoT devices and manages trust through artificial intelligence techniques such as Bayesian networks and fuzzy logic. A detailed description of the proposed system is provided, and its main performances are evaluated. The results prove SETUCOM feasibility in context-aware security and privacy for the smart city.
Characteristics and Development Mechanisms of Northeast Cold Vortices
Authors: Yang Bo , Wang Lijuan , Guan Yuanhong
Published: April 2021

The northeast cold vortices (NECVs) in May-September during 1989–2018 are classified, based on the 6 h NCEP/NCAR reanalysis data (2.5° × 2.5°) and observational data from the Meteorological Information Comprehensive Analysis and Process System (MICAPS) provided by China Meteorological Administration. Meanwhile, characteristics and development mechanisms for NECVs of different types are also analyzed. In the recent 30 years, the occurrences of NECV processes have been increasing year by year, with an average of 7.4 times per year in Northeast China and a duration of 3–5 days on average for each process. NECVs mostly occur in late spring and early summer, and the longest time influenced by NECVs exceeds 19 days, with annual means of 9.9 days, 8.8 days, and 7.0 days in May, June, and July, respectively. The frequency of weak NECVs is about 1.2 times that of strong NECVs. Strong NCVs in late spring and early autumn as well as weak MCVs in summer are with high-frequency occurrences. It is found that when NCVs occur in late spring and early autumn, the upper-level westerly jets are relatively stronger, thus strengthening the divergence in the upper troposphere and the vortex circulation. The circulation fields in upper and lower levels cooperate with the strong jets, promoting the continuous development and maintenance of the cold vortices. Apart from the jets and circulation, the lower central potential height combined with the obvious cold-core and stronger ascending motions favor the NCV’s development. In addition, the dry intrusion has a strong promotion due to the stronger lower-level cold advection and downward intrusion of high potential vorticity. However, when MCVs occur in summer, things are just the opposite.
Spatial‐Temporal Simulations of Soil Moisture Content in a Large Basin of the Loess Plateau, China
Authors: Wang Zhiqi , Feng Xiaobo , Yao Zhihong , Ma Zhaolong , Ji Guodong
Published: April 2021

Soil moisture is a crucial factor limiting the growth and survival of plants on the Loess Plateau. Its level has a severe impact on plants’ growth and development and the type and distribution characteristics of communities. This study area is the Jihe Basin in the Loess Plateau, China. Multiple linear regression models with different environmental variables (land use, topographic and meteorological factors, etc.) were developed to simulate soil moisture’s spatial and temporal changes by integrating field experiments, indoor analysis, and GIS spatial analysis. The model performances were evaluated in the Jihe Basin, with soil moisture content measurements. The result shows that soil moisture content is positively correlated with soil bulk density, monthly rainfall, topographic wetness index, land use coefficient, and slope aspect coefficient but negatively correlated with the monthly‐averaged temperature and the relative elevation coefficient. The selected variables are all related to the soil moisture content and can account for 75% of the variations of soil moisture content, and the remaining 25% of the variations are related to other factors. Comparing the simulated and measured values at all sampling points shows that the average error of all the simulated values is 0.09, indicating that the simulation has high accuracy. The spatial distribution of soil moisture content is significantly affected by land use and topographic factors, and seasonal variation is remarkable in the year. Seasonal variation of soil moisture content is determined by the seasonal variation of rainfall and the air temperature (determining evaporation) and vegetation growth cycle. Therefore, the proposed model can simulate the spatial and temporal variation of soil moisture content and support developing the soil and water loss model on a basin scale.
Epidemiological Survey of Mycoplasma bovis in Yaks on the Qinghai Tibetan Plateau, China
Authors: Niu Jiaqiang , Li Keiwei , Pan Huachun , Gao Xing , Li Jiakui , Wang Dongjing , Yan Mingshuai , Xu Yefen , Sizhu Suolang
Published: April 2021

Mycoplasma bovis (M. bovis) is one of the most important pneumonia pathogens in yaks. It may result in more economic losses due to the cold and anoxia condition at Qinghai Tibetan plateau. However, to date, limited information on M. bovis infection in yaks is available in China. For this purpose, the seroprevalence of M. bovis was investigated in yaks living in the mentioned area through commercial ELISA kits. A total of 959 yaks were incorporated into this study. The prevalence of the disease in yaks was 48.70%. The serological results revealed a relatively high prevalence of M. bovis infection in yaks. The present study may greatly contribute to the prevention of this disease. More importance should be given to the potential threat caused by M. bovis in the special plateau.
Support Vector Machine Weather Prediction Technology Based on the Improved Quantum Optimization Algorithm
Authors: Zhang Jinlei , Qiu Xue , Li Xiang , Huang Zhijie , Wu Mingqiu , Dong Yumin
Published: April 2021

Emotion recognition is a research hotspot in the field of artificial intelligence. If the human‐computer interaction system can sense human emotion and express emotion, it will make the interaction between the robot and human more natural. In this paper, a multimodal emotion recognition model based on many‐objective optimization algorithm is proposed for the first time. The model integrates voice information and facial information and can simultaneously optimize the accuracy and uniformity of recognition. This paper compares the emotion recognition algorithm based on many‐objective algorithm optimization with the single‐modal emotion recognition model proposed in this paper and the ISMS_ALA model proposed by recent related research. The experimental results show that compared with the single‐mode emotion recognition, the proposed model has a great improvement in each evaluation index. At the same time, the accuracy of emotion recognition is 2.88% higher than that of the ISMS_ALA model. The experimental results show that the many‐objective optimization algorithm can effectively improve the performance of the multimodal emotion recognition model.
A DEA-Based Decision Support Framework for Organizations’ Performance Evaluation considering TQM and Knowledge Management
Authors: Karami Azin , Shirouyehzad Hadi , Asadpour Milad
Published: April 2021

Total quality management (TQM) and knowledge management (KM) play a significant role in improving the situation of the organization and creating and maintaining competitive advantage (CA). Therefore, harmonizing TQM and KM with the organizational goals and performance leads to the organization’s greater capabilities. The current paper presents a decision support framework to evaluate the performance of organizations based on the success factors (SFs) of TQM and KM using the BCC model of data envelopment analysis (DEA). The SFs of KM are considered as input and the SFs of TQM are considered as output of the BCC model, and the efficiency scores of five pharmaceutical companies in Esfahan, Iran, are obtained. The results show that, among the aforementioned companies, three companies were recognized as efficient, while two of them were introduced as inefficient companies. Furthermore, in order to provide more recommendations for the managers of these companies, two area charts according to SFs of TQM and KM were drawn, and the results were analyzed and discussed.
[Retracted] Molecular Mechanism of Palmitic Acid on Myocardial Contractility in Hypertensive Rats and Its Relationship with Neural Nitric Oxide Synthase Protein in Cardiomyocytes
Authors: Tan Haibo , Song Weiwei , Liu Sha , Song Qing , Zhou Tiangang , Wang Yidan , Hou Yunfeng
Published: April 2021

Objective. It is aimed at investigating the mechanism of palmitic acid (PA) on myocardial contractility in hypertensive rats and its relationship with myocardial neural nitric oxide synthase (nNOS) protein. Methods. The rats were randomly divided into sham operation group and hypertensive group, with thirty rats in each group, to prepare angiotensin II‐induced hypertensive model rats. The blood pressure of rats was measured by the multianimal multichannel tail cuff noninvasive blood pressure system of Kent Coda, USA. The Ionoptix single‐cell contraction detection system was used to detect myocardial cells. ATP level of left ventricular cardiomyocytes was determined by luminescence method, and protein was measured by Western blot. Results. Compared with the sham group, systolic blood pressure and diastolic blood pressure were increased in the hypertensive group over 4 weeks; PA increased the contractility of left ventricular cardiomyocytes in normal rats, but not in hypertensive rats, and PA increased the intracellular ATP level of rats in the sham group but not in the hypertension group. In the hypertension group, the expression of nNOS in the cardiomyocytes was significantly increased, and specific nNOS inhibitor S‐methyl‐L‐thiocitrulline (SMTC) was found to restore the positive inotropic effect of PA in the myocardium of the hypertension group. PA was supplemented after using CPT‐1 inhibitor etomoxir (ETO); it was found that ETO inhibited the positive inotropic effect of PA on left ventricular cardiomyocytes in the sham group, and PA was supplemented after using SMTC and ETO, it was found that SMTC + ETO could inhibit the positive inotropic effect of PA on left ventricular cardiomyocytes in myocardium of hypertensive rats. Conclusion. PA could increase the contractility of healthy cardiomyocytes, but had no obvious positive effect on the cardiomyocytes of hypertensive rats, PA enhanced the contractility of cardiomyocytes by increasing ATP level in them, and the inhibitory effect of PA on myocardial contractility in hypertensive rats may be related to the increased nNOS and CPT‐1 in cardiomyocytes.
Qiangji Jianli Decoction Alleviates Hydrogen Peroxide‐Induced Mitochondrial Dysfunction via Regulating Mitochondrial Dynamics and Biogenesis in L6 Myoblasts
Authors: Song Jingwei , Li Qing , Ke Lingling , Liang Jian , Jiao Wei , Pan Huafeng , Li Yanwu , Du Qun , Song Yafang , Ji Aidong , Chen Zhiwei , Li Jinqiu , Li Lanqi
Published: April 2021

Oxidative stress can cause the excessive generation of reactive oxygen species (ROS) and has various adverse effects on muscular mitochondria. Qiangji Jianli decoction (QJJLD) is an effective traditional Chinese medicine (TCM) that is widely applied to improve muscle weakness, and it has active constituents that prevent mitochondrial dysfunction. To investigate the protective mechanism of QJJLD against hydrogen peroxide‐ (H2O2‐) mediated mitochondrial dysfunction in L6 myoblasts. Cell viability was determined with MTT assay. Mitochondrial ultrastructure was detected by transmission electron microscope (TEM). ROS and mitochondrial membrane potential (MMP) were analyzed by fluorescence microscope and flow cytometry. The superoxide dismutase (SOD), glutathione peroxidase (GSH‐Px) activity, and malondialdehyde (MDA) level were determined by WST‐1, TBA, and DTNB methods, respectively. The mRNA and protein levels were measured by quantitative real‐time PCR (qRT‐PCR) and Western blot. The cell viability was decreased, and the cellular ROS level was increased when L6 myoblasts were exposed to H2O2. After treatment with QJJLD‐containing serum, the SOD and GSH‐Px activities were increased. MDA level was decreased concurrently. ROS level was decreased while respiratory chain complex activity and ATP content were increased in L6 myoblasts. MMP loss was attenuated. Mitochondrial ultrastructure was also improved. Simultaneously, the protein expressions of p‐AMPK, PGC‐1α, NRF1, and TFAM were upregulated. The mRNA and protein expressions of Mfn1/2 and Opa1 were also upregulated while Drp1 and Fis1 were downregulated. These results suggest that QJJLD may alleviate mitochondrial dysfunction through the regulation of mitochondrial dynamics and biogenesis, the inhibition of ROS generation, and the promotion of mitochondrial energy metabolism.
Cognitive Aftereffects of Acute tDCS Coupled with Cognitive Training: An fMRI Study in Healthy Seniors
Authors: Šimko P. , Pupíková M. , Gajdoš M. , Rektorová I.
Published: April 2021

Enhancing cognitive functions through noninvasive brain stimulation is of enormous public interest, particularly for the aging population in whom processes such as working memory are known to decline. In a randomized double-blind crossover study, we investigated the acute behavioral and neural aftereffects of bifrontal and frontoparietal transcranial direct current stimulation (tDCS) combined with visual working memory (VWM) training on 25 highly educated older adults. Resting-state functional connectivity (rs-FC) analysis was performed prior to and after each stimulation session with a focus on the frontoparietal control network (FPCN). The bifrontal montage with anode over the left dorsolateral prefrontal cortex enhanced VWM accuracy as compared to the sham stimulation. With the rs-FC within the FPCN, we observed significant

stimulation
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interaction using bifrontal tDCS. We found no cognitive aftereffects of the frontoparietal tDCS compared to sham stimulation. Our study shows that a single bifrontal tDCS combined with cognitive training may enhance VWM performance and rs-FC within the relevant brain network even in highly educated older adults.
Reduced Graphene Oxide/Gold Nanoparticles Modified Screen‐Printed Electrode for the Determination of Palmitic Acid
Authors: Ching Chin Boon , Abdullah Jaafar , Yusof Nor Azah
Published: April 2021

Palm oil is one of the major oils and fats produced in the world today. The quality of palm oil is crucial to be investigated, and one of the quality indices is free fatty acid (FFA) content. Therefore, in this study, an electrochemical approach for the determination of FFA has been explored as an alternative to replace the conventional method (titration method). The electrochemical method was developed based on electrochemically reduced graphene oxide (rGO) coupled with gold nanoparticles (AuNPs) deposited onto a screen‐printed carbon electrode (SPCE) via drop‐casting technique. The voltammetric behaviour of 2‐methyl‐1,4‐naphthoquinone (VK3) in the presence of palmitic acid at the modified electrode was investigated in an acetonitrile/water mixture containing lithium perchlorate (LiClO4). The electrochemical detection of palmitic acid was based on the voltammetric reduction of VK3 to form the corresponding hydroquinone which is proportional to the concentration of palmitic acid. Under optimum conditions, the developed method showed a good linear relationship towards palmitic acid in the concentration ranging from 0.192 mM to 0.833 mM with the detection limit of 0.015 mM. The exploration of the developed system is expected to achieve high sensitivity and excellent selectivity towards the determination of FFA content in palm oil.