bluuebunny/crossref_metadata_2025 huggingface dataset:
Pulmonary Embolism in Women: A Systematic Review of the Current Literature
Authors: Thachil Rosy , Nagraj Sanjana , Kharawala Amrin , Sokol Seth I.
Published: July 2022

Cardiovascular disease is the leading cause of death in women. Pulmonary embolism (PE) is the third most-common cause of cardiovascular death, after myocardial infarction (MI) and stroke. We aimed to evaluate the attributes and outcomes of PE specifically in women and explore sex-based differences. We conducted a systematic review of the literature using electronic databases PubMed and Embase up to 1 April 2022 to identify studies investigating PE in women. Of the studies found, 93 studies met the eligibility criteria and were included. The risk of PE in older women (especially >40 years of age) superseded that of age-matched men, although the overall age- and sex-adjusted incidence of PE was found to be lower in women. Risk factors for PE in women included age, rheumatologic disorders, hormone replacement therapy or oral contraceptive pills, pregnancy and postpartum period, recent surgery, immobilization, trauma, increased body mass index, obesity, and heart failure. Regarding pregnancy, a relatively higher incidence of PE has been observed in the immediate postpartum period compared to the antenatal period. Women with PE tended to be older, presented more often with dyspnea, and were found to have higher NT-proBNP levels compared to men. No sex-based differences in in-hospital mortality and 30-day all-cause mortality were found. However, PE-related mortality was higher in women, particularly in hemodynamically stable patients. These differences form the basis of future research and outlets for reducing the incidence, morbidity, and mortality of PE in women.
Identifying Patients with Familial Chylomicronemia Syndrome Using FCS Score-Based Data Mining Methods
Authors: Németh Ákos , Harangi Mariann , Daróczy Bálint , Juhász Lilla , Paragh György , Fülöp Péter
Published: July 2022

Background: There are no exact data about the prevalence of familial chylomicronemia syndrome (FCS) in Central Europe. We aimed to identify FCS patients using either the FCS score proposed by Moulin et al. or with data mining, and assessed the diagnostic applicability of the FCS score. Methods: Analyzing medical records of 1,342,124 patients, the FCS score of each patient was calculated. Based on the data of previously diagnosed FCS patients, we trained machine learning models to identify other features that may improve FCS score calculation. Results: We identified 26 patients with an FCS score of ≥10. From the trained models, boosting tree models and support vector machines performed the best for patient recognition with overall AUC above 0.95, while artificial neural networks accomplished above 0.8, indicating less efficacy. We identified laboratory features that can be considered as additions to the FCS score calculation. Conclusions: The estimated prevalence of FCS was 19.4 per million in our region, which exceeds the prevalence data of other European countries. Analysis of larger regional and country-wide data might increase the number of FCS cases. Although FCS score is an excellent tool in identifying potential FCS patients, consideration of some other features may improve its accuracy.
The Influence of Periodontal Diseases and the Stimulation of Saliva Secretion on the Course of the Acute Phase of Ischemic Stroke
Authors: Pawlukowska Wioletta , Baumert Bartłomiej , Meller Agnieszka , Dziewulska Anna , Zawiślak Alicja , Grocholewicz Katarzyna , Nowacki Przemysław , Masztalewicz Marta
Published: July 2022

Background and purpose: The course of an ischemic stroke depends on many factors. The influence of periodontal diseases and the stimulation of salivation on the course and severity of stroke remains unresolved. Therefore, the aim of the study was to analyze the severity of ischemic stroke depending on the occurrence of periodontal diseases and saliva stimulation. Methods: The severity of the neurological condition was assessed using the NIHSS scale on days one, three and seven of stroke. The incidence of periodontal diseases was classified using the Hall’s scale in the first day of stroke. On days one and seven of stroke, the concentration of IL-1β, MMP-8, OPG and RANKL in the patients’ saliva was assessed using the Elisa technique. At the same time, the level of CRP and the number of leukocytes in the peripheral blood were tested on days one, three and seven of the stroke, and the incidence of upper respiratory and urinary tract infections was assessed. Results:100 consecutive patients with their first ever ischemic stroke were enrolled in the study. 56 randomly selected patients were subjected to the stimulation of salivation, the remaining patients were not stimulated. In the study of the severity of the neurological condition using the NIHS scale on days three and seven of stroke, the degree of deficit in patients without periodontal disease significantly improved compared to patients with periodontal disease, respectively (p < 0.01 and p = 0.01). Patients from the stimulated group had more severe neurological deficit at baseline (p = 0.04). On days three and seven of neurological follow-up, the condition of patients from both groups improved with a further distinct advantage of the unstimulated group over the stimulated group, respectively (p = 0.03 and p < 0.001). In patients from both groups, a statistically significant decrease in CRP and lymphocyte levels was observed on day seven in relation to day one. Conclusions: The occurrence of periodontal disease in a patient with stroke affects the severity of stroke. Stimulation of the mouth and salivary glands in these patients may have a positive effect on the course of stroke, taking into account the dynamics of neurological symptoms.
European Kidney Function Consortium Equation vs. Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) Refit Equations for Estimating Glomerular Filtration Rate: Comparison with CKD-EPI Equations in the Korean Population
Authors: Kim Hanah , Hur Mina , Lee Seungho , Lee Gun-Hyuk , Moon Hee-Won , Yun Yeo-Min
Published: July 2022

The Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation is the most commonly used equation for estimated glomerular filtration rate (eGFR). Recently, the European Kidney Function Consortium (EKFC) announced a full-age spectrum equation, and the CKD-EPI announced the CKD-EPI refit equations (CKD-EPI-R). We compared CKD-EPI, EKFC, and CKD-EPI-R equations in a large-scale Korean population and investigated their potential implications for CKD prevalence. In a total of 106,021 individuals who received annual check-ups from 2018 to 2020, we compared the eGFR equations according to the Clinical and Laboratory Standards Institute guidelines. Weighted kappa (κ) agreement was used to compare the potential implications for CKD prevalence across the equations. The median value of eGFR tended to increase in the order of EKFC, CKD-EPI, and CKD-EPI-R equations (92.4 mL/min/1.73 m2, 96.0 mL/min/1.73 m2, and 100.0 mL/min/1.73 m2, respectively). The EKFC and CKD-EPI-R equations showed a very high correlation of eGFR and good agreement for CKD prevalence with CKD-EPI equation (r = 0.98 and 1.00; κ = 0.80 and 0.82, respectively). Compared with the CKD-EPI equation, the EFKC equation overestimated CKD prevalence (3.5%), and the CKD-EPI-R equation underestimated it (1.5%). This is the first study comparing CKD-EPI, EKFC, and CKD-EPI-R equations simultaneously. The EKFC and CKD-EPI-R equations were statistically interchangeable with CKD-EPI equations in this large-scale Korean population. The transition of eGFR equations, however, would lead to sizable changes in the CKD prevalence. To improve kidney health, in-depth discussion considering various clinical aspects is imperative for the transition of eGFR equations.
Immunomodulation Effect of Biomaterials on Bone Formation
Authors: Zhao Tong , Chu Zhuangzhuang , Ma Jun , Ouyang Liping
Published: July 2022

Traditional bone replacement materials have been developed with the goal of directing the osteogenesis of osteoblastic cell lines toward differentiation and therefore achieving biomaterial-mediated osteogenesis, but the osteogenic effect has been disappointing. With advances in bone biology, it has been revealed that the local immune microenvironment has an important role in regulating the bone formation process. According to the bone immunology hypothesis, the immune system and the skeletal system are inextricably linked, with many cytokines and regulatory factors in common, and immune cells play an essential role in bone-related physiopathological processes. This review combines advances in bone immunology with biomaterial immunomodulatory properties to provide an overview of biomaterials-mediated immune responses to regulate bone regeneration, as well as methods to assess the bone immunomodulatory properties of bone biomaterials and how these strategies can be used for future bone tissue engineering applications.
Online Assessment of Morphological Awareness in Grades 2–4: Its Development and Relation to Reading Comprehension
Authors: Varga Szilvia , Pásztor Attila , Stekács János
Published: July 2022

The aims of the study are to construct an online instrument to assess different aspects of morphological awareness and to examine its development and its relation to reading comprehension in grades 2–4 in Hungarian children. Altogether, 4134 students were tested. The online test evaluated inflectional, derivational, and compound morphological skills with five subtests. The instrument proved to be reliable. CFA examinations revealed that the five subtests were empirically distinguishable dimensions. Inflectional, derivational, and compound morphology as the three main dimensions of morphological awareness were also empirically supported by our data. Morphological awareness skills improved significantly and developed in parallel with reading skills throughout grades 2–4. The increase in the development of morphological awareness from grade 2 to grade 3 tends to be faster than the growth between grade 3 and 4. Positive moderate correlations were found between morphological skills and reading comprehension and the relationships seem to be stable throughout the three grades. The most significant predictor of reading comprehension is the Affix Identification for Nonwords subtest. Our study showed that morphological awareness could be assessed efficiently through online media and drew attention to the importance of morphological awareness in the development of reading comprehension and linguistic intelligence.
Diet of Adult Sardine Sardina pilchardus in the Gulf of Trieste, Northern Adriatic Sea
Authors: Borme Diego , Legovini Sara , de Olazabal Alessandra , Tirelli Valentina
Published: July 2022

Food availability is thought to exert a bottom-up control on the population dynamics of small pelagic fish; therefore, studies on trophic ecology are essential to improve their management. Sardina pilchardus is one of the most important commercial species in the Adriatic Sea, yet there is little information on its diet in this area. Adult sardines were caught in the Gulf of Trieste (northern Adriatic) from spring 2006 to winter 2007. Experimental catches conducted over 24-h cycles in May, June and July showed that the sardines foraged mainly in the late afternoon. A total of 96 adult sardines were analysed: the number of prey varied from a minimum of 305 to a maximum of 3318 prey/stomach, with an overall mean of 1259 ± 884 prey/stomach. Prey items were identified to the lowest possible taxonomical level, counted and measured at the stereo-microscope. Overall, sardines fed on a wide range of planktonic organisms (87 prey items from 17 μm to 18.4 mm were identified), with copepods being the most abundant prey (56%) and phytoplankton never exceeding 10% of the prey. Copepods of the Clauso-Paracalanidae group and of the genus Oncaea were by far the most important prey. The carbon content of prey items was indirectly estimated from prey dry mass or body volume. Almost all carbon uptake relied on a few groups of zooplankton. Ivlev’s selectivity index showed that sardines positively selected small preys (small copepods < 1 mm size), but also larger preys (such as teleost eggs, decapod larvae and chaetognaths), confirming their adaptive feeding capacity.
Preservation of Transgressive System Tract Geomorphic Elements during the Holocene Sea Level Rise in the South-Eastern Sicilian Tyrrhenian Margin
Authors: Distefano Salvatore , Gamberi Fabiano
Published: July 2022

Understanding of complex sedimentary records formed by transgressive systems is critical because they provide information on sea level changes which control the evolution of the coastal environment. This paper discusses the preservation of the Transgressive System Tracts (TST) in the south-eastern Sicilian Tyrrhenian margin during the last Holocene eustatic cycle. The available dataset consists of high-resolution bathymetry (multibeam), whose description and interpretation through a Digital Elevation Model (DEM) has been integrated with six seismic profiles (CHIRP). Within the whole study area, four bathymetric contours (−120 m, −100 m, −80 m and −70 m) were identified and assumed as the markers of the main locations of the paleo-coastlines, corresponding with the steps of the main changes in the sea level. The transgressive deposits are preferentially preserved in the 70–100 m bathymetric range, bounded at the top by the maximum flooding surface and consisting of the relict geomorphic elements that represent past landscapes (coastal barrier lagoons, transgressive sheet areas, cuspate beaches, transgressive dune-field systems). Furthermore, with the support of 3D bathymetric maps, a reconstruction of the geomorphological evolution of the past coastal systems during the last transgressive stage is also provided.
Modified Method for Determination of Wear Coefficient of Reciprocating Sliding Wear and Experimental Comparative Study
Authors: Liu Tongmu , Yu Jianxing , Wang Huakun , Yu Yang , Li Haoda , Zhou Baocheng
Published: July 2022

A modified method for predicting the wear coefficient of reciprocating sliding wear was proposed in this study, which is less time-consuming. Based on this method, reciprocating sliding wear tests of three chain alloys (CM490, SS316, and TC4) under different loadings were conducted and the friction coefficient, wear coefficient, and wear morphology were obtained and compared. The results indicated that the time-variant coefficient of friction (CoF) could be used as an indicator for the stable wear state; moreover, it also changes periodically with the wear direction. Statistical analysis of friction coefficient indicated that it follows bimodal distribution or multimodal distribution. The friction and wear behaviors of CM490 and SS316 were different from those of TC4, and a detailed micro-morphological analysis indicated that the discrepancy is caused by the difference in the quantity and size of the wear debris. Furthermore, an upper limit of the contact stress-dependent wear coefficient was also observed, and the variability of the wear coefficient was also analyzed.
Formation Control of Multiple Underactuated Surface Vessels with a Disturbance Observer
Authors: Sun Zhiyuan , Sun Hanbing , Li Ping , Zou Jin
Published: July 2022

To maintain the formation of underactuated surface vessels (USVs), this study designs a formation controller based on a virtual structure strategy. The problem of formation control is transformed into the problems of tracking the USV position and the virtual structure point position. Meanwhile, to eliminate the effects of model parameter uncertainties and external environment disturbances on USV tracking control, a compensation control algorithm based on disturbance estimation is proposed. The Lyapunov theorem is introduced to ensure that the trajectory tracking error of the proposed control algorithm eventually converges to any small region, which confirms global stability of the designed tracking error. The simulation results demonstrate that the proposed controller can eliminate the effect of external uncertain interference and maintain the formation of multiple USVs.
Modeling Bivariate Dependency in Insurance Data via Copula: A Brief Study
Authors: Ghosh Indranil , Watts Dalton , Chakraborty Subrata
Published: July 2022

Copulas are a quite flexible and useful tool for modeling the dependence structure between two or more variables or components of bivariate and multivariate vectors, in particular, to predict losses in insurance and finance. In this article, we use the VineCopula package in R to study the dependence structure of some well-known real-life insurance data and identify the best bivariate copula in each case. Associated structural properties of these bivariate copulas are also discussed with a major focus on their tail dependence structure. This study shows that certain types of Archimedean copula with the heavy tail dependence property are a reasonable framework to start in terms modeling insurance claim data both in the bivariate as well as in the case of multivariate domains as appropriate.
Spatial and Temporal Characteristics of Evapotranspiration in the Upper Minjiang River Basin Based on the SiB2 Model
Authors: Kong Bo , He Bing , Liu Xiangmeng , Yu Huan
Published: July 2022

The evapotranspiration (ET) in mountainous watersheds affects the security of downstream water supply and ecological safety. Continuous time-varying ET cannot be obtained by traditional methods such as remote sensing and ground observations. In this study, a simple biosphere model 2 (SiB2) was parameterized in a typical mountainous area, the upper Minjiang River, using field observations and remote sensing data. The performance of SiB2 was then assessed by comparing it with direct measurements of the evaporation dishes. The results showed that (1) at the daily scale, the simulated ET was smaller than the measured ET. At the monthly scale, the relative errors between the simulated and measured values ranged from 1.48% to 20.72%. The relative error between the simulated and measured values of the total annual ET is 6.99%; (2) the ET of Minjiang River was characterized by a “bimodal” variation, with lower daily ET from November to February (non-growing season) and higher daily ET from March to August (growing season); (3) the ET of Minjiang River showed the spatial characteristics of low in the northwest and high in the southeast, with a high-value center located in Dujiangyan City. In summary, SiB2 is suitable for simulating ET in mountainous watersheds with spatial and temporal continuity. This study can contribute to the enhancement of water resources use planning and basin management in the upper Minjiang River.
To Settle Down, or Not? Evaluating the Policy Effects of Talent Housing in Shanghai, China
Authors: Tao Li , Lei Xiaoyan , Guo Wentan , Li Victor Jing , Cheng Min
Published: July 2022

Housing has become pivotal in attracting and retaining talent in first-tier cities. Although numerous cities are actively promoting the provision of talent housing in China, little is known about the talent’s evaluations of talent housing policies or the effect on their urban settlement intention. This paper aims to investigate whether talent housing alleviates the housing difficulties of talent and its role in retaining talent. A questionnaire was conducted face-to-face in talent housing in Shanghai. Binary logistic regression was employed to analyse the factors significantly contributing to the settlement intentions of the talent. Talent housing was confirmed to alleviate the talent’s housing pressures and further increase their urban settlement intention. The local hukou was determined to be crucial in accelerating the willingness of talent to settle in Shanghai. However, housing affordability (including school district housing) may jeopardise such positive effects. It is crucial to provide more choices of talent housing and increase the coverage of good-quality educational resources. In the long run, more talent can be attracted and retained in the locality under a broader coverage of the talent housing scheme.
Nano-Graphite Prepared by Rapid Pulverization as Anode for Lithium-Ion Batteries
Authors: Liu Wei , Zong Kai , Li Ying , Deng Yonggui , Hussain Arshad , Cai Xingke
Published: July 2022

Reducing the particle size of active material is an effective solution to the poor rate performance of the lithium-ion battery. In this study, we proposed a facile strategy for the preparation of nano-graphite as an anode for a lithium-ion battery via the rapid mechanical pulverization method. It is the first time that diamond particle was selected as the medium to achieve high preparation efficiency and low energy consumption. The as-prepared nano-graphite with the size from 10 to 300 nm displays an intact structure and high specific surface area. The introduced oxygen atoms increased the wettability of nano-graphite electrode and lowered its polarization. The nano-graphite prepared from three hours of grinding shows an excellent reversible capacity of 191 mAh g−1, at a rate of 5 C, after 480 cycles, along with an increase of 86% in capacity, at 1 C, in comparison with pristine graphite. The highlight of this strategy is to optimize the current preparation method. The good electrochemical performance comes from the combined effect of nano-scale particle size, large specific surface area, and continuous mesopores.
Transport Property and Spin–Orbit Torque in 2D Rashba Ferromagnetic Electron Gas
Authors: Yang Chao , Zhou Da-Kun , Wang Ya-Ru , Wang Zheng-Chuan
Published: July 2022

In this paper, we investigate the spin–orbit torque and transport property in a 2D Rashba ferromagnetic electron gas. The longitudinal conductivity can be divided into two parts: the first term is determined by the charge density and is independent of the spin degrees of freedom. The second term depends on the two bands that spin in the opposite directions, and it is directly proportional to spin–orbit torque regardless of the band structure and temperature. This is a general and underlying relation between the transport property and spin–orbit torque. Moreover, we show the impacts of the spin–orbit coupling constant and Fermi energy on transverse conductivity and spin–orbit torque, which is helpful for relevant experiments.
A Novel Alveolar Distractor Incorporating Nickel–Titanium Alloy Springs: A Preliminary In Vitro Study
Authors: Chancharoen Sarun , Santiwong Peerapong , Seriwatanachai Dutmanee , Khantachawana Anak , Chintavalakorn Rochaya
Published: July 2022

A new design of an alveolar distractor using nickel–titanium (NiTi) open-coil springs was developed and investigated to produce distraction forces against the tensile forces of porcine attached gingiva to simulate human gingiva. We subjected 15 mm long NiTi open-coil springs (Highland and ORMCO) with three levels of forces (light, medium and heavy) to mechanical testing in a 37 ± 1 °C water bath. Ten strips of porcine mandibular attached gingiva were subjected to tensile tests to determine the resistance force. The forces from the springs were compared with the tensile forces from the porcine attached gingiva. Data between groups were analyzed with independent-samples T-tests (p-value < 0.05). The tensile strength and the Young modulus were greater in buccal compared to lingual porcine attached gingiva. Compared to other spring dimensions and companies, forces generated from 0.014 × 0.036″ ORMCO springs were the highest and could overcome the tensile resistance from porcine attached gingiva over the longest distraction range of 1.6 mm. This preliminary in vitro study introduced a new design of an alveolar distractor incorporated with NiTi open-coil springs that could generate light and continuous forces to overcome the resistance from porcine attached gingiva.
Development and Investigation of High Performance PVA/NiO and PVA/CuO Nanocomposites with Improved Physical, Dielectric and Mechanical Properties
Authors: Faiza  , Malik Zahida , Khattak Abraiz , Alahmadi Ahmad , Butt Safi
Published: July 2022

A series of polyvinyl alcohol (PVA)based composites with well dispersed nano fillers were fabricated and compared in terms of dielectric, mechanical, and optical properties. Specifically, NiO and CuO nano-fillers were utilized in a range of 0.2–0.6 wt% for thin film fabrication by solution deposition method. The characterization of nanocomposites was confirmed through FTIR, FESEM, and XRPD, whereas dielectric and mechanical properties were analyzed with respect to the filler concentrations. The bandgap of PVA/nano-filler composites reduced with an increase in NiO and CuO concentration from 0.2 to 0.6 wt%. The increase in the permittivity of the material was observed for 6 wt% of nano-fillers. The toughness of PVA/nano-filler composites was improved by increasing CuO and NiO concentration and Young’s modulus of 30.9 and 27.2 MPa for 0.6 wt% of NiO and CuO-based nanocomposite, respectively, was observed. The addition of nano-fillers showed improved optical, dielectric, and mechanical properties.
Enhancement of Domain Wall Pinning in High-Temperature Resistant Sm2Co17 Type Magnets by Addition of Y2O3
Authors: Liu Zhuang , Zhang Chaoyue , Wu Haichen , Chen Renjie , Yan Aru
Published: July 2022

In this study, the effects of Y2O3 addition on the magnetic properties, microstructure and magnetization reversal behavior of Sm(Co0.79Fe0.09Cu0.09Zr0.03)7.68 magnet were investigated. By addition of Y2O3, the coercivity was increased from 21.34 kOe to 27.42 kOe at 300 K and from 5.14 kOe to 6.27 kOe at 823 K. A magnet with a maximum magnetic energy product of 9.86 MGOe at 823 K was obtained. With the interdiffusion of Y and Sm after appropriate addition, the Cu content within the cell boundary phase close to the oxide was detected to be nearly twice as high as that away from the oxide. We report for the first time that a collection of lamellar phases were formed on both sides of the inserted oxide, providing a strong pinning field against magnetic domain wall motion based on in-situ Lorentz TEM observation. Furthermore, the ordering process of the original magnet was delayed after Y2O3 addition, resulting in the refinement of cellular structure, which can also enhance the domain wall pinning ability of cellular structures based on micromagnetic simulation. However, excessive addition of Y2O3 led to large Cu-rich phase and Zr-rich impurity phase precipitated at the edge of the oxide, resulting in the destruction of cellular structures and a significant reduction in coercivity. This study provides a new technical approach to regulate the microstructure of Sm2Co17 type magnets. Addition of Y2O3 is expected to play a significant role in improvement of high temperature magnetic properties.
Correlation of Bone Material Model Using Voxel Mesh and Parametric Optimization
Authors: Pietroń Kamil , Mazurkiewicz Łukasz , Sybilski Kamil , Małachowski Jerzy
Published: July 2022

The authors present an algorithm for determining the stiffness of the bone tissue for individual ranges of bone density. The paper begins with the preparation and appropriate mechanical processing of samples from the bovine femur and their imaging using computed tomography and then processing DICOM files in the MIMICS system. During the processing of DICOM files, particular emphasis was placed on defining basic planes along the sides of the samples, which improved the representation of sample geometry in the models. The MIMICS system transformed DICOM images into voxel models from which the whole bone FE model was built in the next step. A single voxel represents the averaged density of the real sample in a very small finite volume. In the numerical model, it is represented by the HEX8 element, which is a cube. All voxels were divided into groups that were assigned average equivalent densities. Then, the previously prepared samples were loaded to failure in a three-point bending test. The force waveforms as a function of the deflection of samples were obtained, based on which the global stiffness of the entire sample was determined. To determine the stiffness of each averaged voxel density value, the authors used advanced optimization analyses, during which numerical analyses were carried out simultaneously, independently mapping six experimental tests. Ultimately, the use of genetic algorithms made it possible to select a set of stiffness parameters for which the error of mapping the global stiffness for all samples was the smallest. The discrepancies obtained were less than 5%, which the authors considered satisfactory by the authors for such a heterogeneous medium and for samples collected from different parts of the bone. Finally, the determined data were validated for the sample that was not involved in the correlation of material parameters. The stiffness was 7% lower than in the experimental test.
Study on Axial Tensile Strain Rate Effect on Concrete Based on Experimental Investigation and Numerical Simulation
Authors: Sun Bi , Chen Rui , Ping Yang , Zhu Zhende , Wu Nan
Published: July 2022

The material of concrete is a three-phase composite material composed of an aggregate, a mortar and an interface transition zone (ITZ). Based on this characteristic, the axial tensile test of mortar, the interface and concrete specimens under intermediate strain rate was carried out in this paper. The sensitivity of these three materials to strain rate was compared and analyzed. The numerical simulation of the axial tension of the concrete materials was studied. The following conclusions are drawn: in the axial tension test, the rate of sensitivity of the specimen interface is the strongest. With the increase in strain rate, the tensile strength and elastic modulus of concrete specimens increase but the effect of the ITZ decreases. The low tensile strength of the ITZ leads to its failure in concrete. The parallel bond strain energy and the dissipated energy of specimens increase with the strain rate. When the strain rate is higher (greater than 1 × 10−2), the increase rate of the dissipated energy is greater than that of the parallel bond strain energy. The results of this research can provide the corresponding basis for the safety evaluation and the stability analysis of concrete engineering in the range of intermediate strain rate.
Corrosion Behavior of Friction Stir Welded AA8090-T87 Aluminum Alloy
Authors: Shyamlal Chandrasekaran , Shanmugavel Rajesh , Jappes J. T. Winowlin , Nair Anish , Ravichandran M. , Abuthakeer S. Syath , Prakash Chander , Dixit Saurav , Vatin N. I.
Published: July 2022

Aerospace alloys with reduced wall thickness but possessing higher hardness, good tensile strength and reasonable corrosion resistance are essential in manufacturing of structures such as fuselage. In this work, friction stir welding has been carried out on such an aerospace aluminum alloy AA8090 T87 which contains 2.3% lithium. Tool rotational speed of 900 rpm and traverse speeds of 90 mm/min., 110 mm/min. are the welding parameters. Hardness analysis, surface roughness analysis and corrosion analysis are conducted to analyze the suitability of the joint for the intended application. The samples were corrosion tested in acid alkali solution and they resulted in the formation of pits of varying levels which indicate the extent of surface degradation. Hardness of the samples was measured after corrosion analysis to observe the changes. The analysis suggests that the change in tool traverse speed transformed the corrosion behavior of the joint and affected both the hardness and surface roughness which mitigated the quality of the joint.
Synthesis and Anticancer Activity of Bagasse Xylan/Resveratrol Graft-Esterified Composite Nanoderivative
Authors: Zhao Bin , Li Heping , Su Yue , Tian Kexin , Zou Zhiming , Wang Wenli
Published: July 2022

Biomass materials are high-quality raw materials for the preparation of natural, green and highly active functional materials due to their rich active groups, wide sources and low toxicity. Bagasse xylan (BX) and resveratrol (Res) were used as raw materials to introduce ethylene glycol dimethacrylate (EGDMA) via grafting reaction to obtain the intermediate product BX/Res-g-EGDMA. The intermediate was esterified with 3-carboxyphenylboronic acid (3-CBA) to obtain the target product 3-CBA-BX/Res-g-EGDMA. The BX/Res-composite-modified nanoderivative with antitumor activity was synthesized with the nanoprecipitation method. The effects of the reaction conditions on the grafting rate (G) of BX/Res-g-EGDMA and the degree of substitution (DS) of 3-CBA-BX/Res-g-EGDMA were investigated using single-factor experiments. The results showed that under the optimized process conditions, G and DS reached 142.44% and 0.485, respectively. The product was characterized with FTIR, XRD, TG-FTC, 1H NMR and SEM, and its anticancer activity was simulated and tested. The results showed that 3-CBA-BX/Res-g-EGDMA had a spherical structure with an average particle size of about 100 nm and that its crystalline structure and thermal stability were different from those of the raw materials. In addition, 3-CBA-BX/Res-g-EGDMA showed the best docking activity with 2HE7 with a binding free energy of −6.3 kJ/mol. The inhibition rate of 3-CBA-BX/Res-g-EGDMA on MGC80-3 (gastric cancer cells) reached 36.71 ± 4.93%, which was 18 times higher than that of BX. Therefore, this material could be a potential candidate for biomedical applications.
Mechanical Properties, Constitutive Behaviors and Failure Criteria of Al-PTFE-W Reactive Materials with Broad Density
Authors: Sun Tao , Liu Aoxin , Ge Chao , Yuan Ying , Wang Haifu
Published: July 2022

Quasi-static tension tests, quasi-static compression tests and dynamic compression tests were conducted to investigate the mechanical properties, constitutive behaviors and failure criteria of aluminum-polytetrafluoroethylene-tungsten (Al-PTFE-W) reactive materials with W content from 20% to 80%. The analysis of the quasi-static test results indicated that the strength of the materials may be independent of the stress state and W content. However, the compression plasticity of the materials is significantly superior to its tension plasticity. W content has no obvious influence on the compression plasticity, while tension plasticity is extremely sensitive to W content. Dynamic compression test results demonstrated the strain rate strengthening effect and the thermal softening effect of the materials, yet the dynamic compression strengths and the strain rate sensitivities of the materials with different W content show no obvious difference. Based on the experimental results and numerical iteration, the Johnson–Cook constitutive (A, B, n, C and m) and failure parameters (D1~D5) were well determined. The research results will be useful for the numerical studies, design and application of reactive materials.
Design and Hydrodynamic Experiment Research on Novel Biomimetic Pectoral Fins of a Ray-Inspired Robotic Fish
Authors: Chen Lingkun , Bi Shusheng , Cai Yueri , Qiu Hongcheng
Published: July 2022

Bionic propulsion has certain advantages over traditional propellers. Much research on pectoral fins as bionic propellers for ray-inspired robots has been made, but rarely did they compare the hydrodynamic performance of different fins on the same platform to find out optimal balance. In this paper, the existing prototypes are categorized into three structure types, and a new bionic pectoral fin module used on a ray-inspired robotic fish was presented, together with a novel 2-DOF spatial parallel mechanism as the bionic propeller. Motion analysis of the mechanism agreed well with the pectoral fin kinematic model, providing a reliable basis to test different types of fins. Design and fabrication of the new bionic fin module as well as two traditional ones are also explained. Hydrodynamic experiment was conducted to study the differences between each fin type under various working conditions. Results indicate that the thrust generated by the fin oscillation is closely related to four parameters (amplitude, frequency, phase difference, and flow velocity), and there are optimal value ranges for better propelling performance when the frequency is around 0.5 Hz and phase difference is near 30°. Thanks to better profile preservation and hydro force interaction, the newly proposed pectoral fins had higher performance than the traditional ones in terms of thrust generation and controllability when the amplitude is higher than 30° and frequency is over 0.3 Hz. An average thrust of 2.98 N was recorded for the new fin module at the max amplitude of 60°, 11.6% and 16.4% higher than the other two comparative test groups, respectively.
Nonlinear Control of a Hydraulic Exoskeleton 1-DOF Joint Based on a Hardware-In-The-Loop Simulation
Authors: Su Qiying , Pei Zhongcai , Tang Zhiyong
Published: July 2022

Aiming at the difficulty of debugging the exoskeleton control system driven by a hydraulic cylinder, a research method of a nonlinear control strategy for the hydraulic exoskeleton system with 1 degree of freedom (DOF) joint is proposed. Based on a hardware-in-the-loop (HIL) simulation, this method establishes the dynamic model of the 1-DOF joint system of the hydraulic driven exoskeleton, constructs the HIL simulation test platform based on the Linux real-time kernel patch, and studies the nonlinear control strategy of the 1-DOF joint system on this platform system. The control effects of the PID control algorithm and the backstepping method on nonlinear control are compared, and the controller parameters are tested on the HIL simulation platform. From the experimental results of the HIL simulation, the research method has the advantages of low cost, high efficiency of system development, safety, and reliability. It has important reference value for the development and debugging of a hydraulic exoskeleton control system.
Weighted Log-Rank Test for Clinical Trials with Delayed Treatment Effect Based on a Novel Hazard Function Family
Authors: Qian Kaihuan , Zhou Xiaohua
Published: July 2022

In clinical trials with delayed treatment effect, the standard log-rank method in testing the difference between survival functions may have problems, including low power and poor robustness, so the method of weighted log-rank test (WLRT) is developed to improve the test performance. In this paper, a hyperbolic-cosine-shaped (CH) hazard function family model is proposed to simulate delayed treatment effect scenarios. Then, based on Fleming and Harrington’s method, this paper derives the corresponding weight function and its regular corrections, which are powerful in test, theoretically. Alternative methods of parameters selection based on potential information are also developed. Further, the simulation study is conducted to compare the power performance between CH WLRT, classical WLRT, modest weighted log-rank test and WLRT with logistic-type weight function under different hazard scenarios and simulation settings. The results indicate that the CH statistics are powerful and robust in testing the late difference, so the CH test is useful and meaningful in practice.
Artificial Bee Colony Algorithm with Nelder–Mead Method to Solve Nurse Scheduling Problem
Authors: Muniyan Rajeswari , Ramalingam Rajakumar , Alshamrani Sultan S. , Gangodkar Durgaprasad , Dumka Ankur , Singh Rajesh , Gehlot Anita , Rashid Mamoon
Published: July 2022

The nurse scheduling problem (NSP) is an NP-Hard combinatorial optimization scheduling problem that allocates a set of shifts to the group of nurses concerning the schedule period subject to the constraints. The objective of the NSP is to create a schedule that satisfies both hard and soft constraints suggested by the healthcare management. This work explores the meta-heuristic approach to an artificial bee colony algorithm with the Nelder–Mead method (NM-ABC) to perform efficient nurse scheduling. Nelder–Mead (NM) method is used as a local search in the onlooker bee phase of ABC to enhance the intensification process of ABC. Thus, the author proposed an improvised solution strategy at the onlooker bee phase with the benefits of the NM method. The proposed algorithm NM-ABC is evaluated using the standard dataset NSPLib, and the experiments are performed on various-sized NSP instances. The performance of the NM-ABC is measured using eight performance metrics: best time, standard deviation, least error rate, success percentage, cost reduction, gap, and feasibility analysis. The results of our experiment reveal that the proposed NM-ABC algorithm attains highly significant achievements compared to other existing algorithms. The cost of our algorithm is reduced by 0.66%, and the gap percentage to move towards the optimum value is 94.30%. Instances have been successfully solved to obtain the best deal with the known optimal value recorded in NSPLib.
A New Approach to Determine the Minimal Polynomials of Binary Modified de Bruijn Sequences
Authors: Musthofa  , Wijayanti Indah Emilia , Palupi Diah Junia Eksi , Ezerman Martianus Frederic
Published: July 2022

A binary modified de Bruijn sequence is an infinite and periodic binary sequence derived by removing a zero from the longest run of zeros in a binary de Bruijn sequence. The minimal polynomial of the modified sequence is its unique least-degree characteristic polynomial. Leveraging a recent characterization, we devise a novel general approach to determine the minimal polynomial. We translate the characterization into a problem of identifying a Hamiltonian cycle in a specially constructed graph. The graph is isomorphic to the modified de Bruijn–Good graph. Along the way, we demonstrate the usefulness of some computational tools from the cycle joining method in the modified setup.
Application and CFD-Based Optimization of a Novel Porous Object for Confined Slot Jet Impingement Cooling Systems under a Magnetic Field
Authors: Aich Walid , Selimefendigil Fatih , Ayadi Badreddine , Ben Said Lotfi , Alshammari Badr M. , Kolsi Lioua , Betrouni Sid Ali , Gasmi Hatem
Published: July 2022

A novel porous object for the control of the convective heat transfer of confined slot nanojet impingement is offered under magnetic field effects, while optimization-assisted computational fluid dynamics is used to find the best working conditions to achieve the best performance of the system. The flow, thermal patterns, and heat transfer characteristics were influenced by the variation in rotational Reynolds number (Rew), Hartmann number (Ha), permeability of the porous object (Da) and its location (Mx). There was a 14.5% difference in the average Nusselt number (Nu) at the highest Rew when motionless object configuration at Ha = 5 was compared, while it was less than 2% at Ha = 25. At Rew = −600, the average Nu variation was 22% when cases with the lowest and highest magnetic field strength were compared. The porous object provides an excellent tool for convective heat transfer control, while the best performance was achieved by using optimization-assisted computational fluid dynamics. The optimal sets of (Rew, Da, Mx, AR) for porous object were (−315.97, 0.0188, −1.456, 0.235), (−181.167, 0.0167, −1.441, 0.2), and (−483.13, 0.0210, −0.348, 0.2) at Ha = 5, 10, and 25, respectively. At the optimal operating point, the local Nu enhancements were 19.46%, 44.86%, and −0.54% at Ha = 5, 10, and 15, respectively, when the no-object case was compared, while the average values were 7.87%, 8.09% and 5.04%.
On the Double ARA-Sumudu Transform and Its Applications
Authors: Saadeh Rania , Qazza Ahmad , Burqan Aliaa
Published: July 2022

The main purpose of this work is to present a new double transform called the double ARA-Sumudu transform (DARA-ST). The application of the new double transform to some basic functions and the master properties are introduced. The convolution and existence theorems are also presented and proved. These new results are implemented to obtain the solution of partial differential equations (PDEs), integral equations (IEs) and functional equations. We obtain new formulas for solving families of PDEs. The latter ones are used to obtain exact solutions of some familiar PDEs such as the telegraph equation, the advection–diffusion equation, the Klein–Gordon equation and others. Moreover, a simple formula for solving a special kind of integral equations is presented and implemented in some applications. The outcomes show that DARA-ST is useful and efficient in handling such kinds of equations.
Deep Adversarial Learning Triplet Similarity Preserving Cross-Modal Retrieval Algorithm
Authors: Li Guokun , Wang Zhen , Xu Shibo , Feng Chuang , Yang Xiaohan , Wu Nannan , Sun Fuzhen
Published: July 2022

The cross-modal retrieval task can return different modal nearest neighbors, such as image or text. However, inconsistent distribution and diverse representation make it hard to directly measure the similarity relationship between different modal samples, which causes a heterogeneity gap. To bridge the above-mentioned gap, we propose the deep adversarial learning triplet similarity preserving cross-modal retrieval algorithm to map different modal samples into the common space, allowing their feature representation to preserve both the original inter- and intra-modal semantic similarity relationship. During the training process, we employ GANs, which has advantages in modeling data distribution and learning discriminative representation, in order to learn different modal features. As a result, it can align different modal feature distributions. Generally, many cross-modal retrieval algorithms only preserve the inter-modal similarity relationship, which makes the nearest neighbor retrieval results vulnerable to noise. In contrast, we establish the triplet similarity preserving function to simultaneously preserve the inter- and intra-modal similarity relationship in the common space and in each modal space, respectively. Thus, the proposed algorithm has a strong robustness to noise. In each modal space, to ensure that the generated features have the same semantic information as the sample labels, we establish a linear classifier and require that the generated features’ classification results be consistent with the sample labels. We conducted cross-modal retrieval comparative experiments on two widely used benchmark datasets—Pascal Sentence and Wikipedia. For the image to text task, our proposed method improved the mAP values by 1% and 0.7% on the Pascal sentence and Wikipedia datasets, respectively. Correspondingly, the proposed method separately improved the mAP values of the text to image performance by 0.6% and 0.8% on the Pascal sentence and Wikipedia datasets, respectively. The experimental results show that the proposed algorithm is better than the other state-of-the-art methods.
Provably Secure Linearly Homomorphic Aggregate Signature Scheme for Electronic Healthcare System
Authors: Gu Yanyan , Shen Limin , Zhang Futai , Xiong Jinbo
Published: July 2022

In recent years, deploying Internet of Things (IoT) in electronic healthcare systems (EHS) has made great progress in healthcare detection. It is extremely important to reduce the cost of communication and ensure the authenticity and integrity of data. A linearly homomorphic signature scheme can solve the above problems. However, when the scale of EHS is too large, the transmission, storage and verification of signatures need a high cost. An aggregate signature can combine many signatures generated by many different users into a short one. Therefore, only one aggregate signature needs to be processed during verification, transmission and storage. Combining the advantages of aggregate signature and linearly homomorphic signature, this paper proposes an aggregate signature scheme based on a linearly homomorphic signature for EHS, which has both linear homomorphism and aggregation, and realizes double data compression. Moreover, our scheme can resist a potential real attack, named a coalition attack. The security of this scheme is rigorously demonstrated based on the computational Diffie–Hellman assumption in the random oracle model.