bluuebunny/crossref_metadata_2025 huggingface dataset:
Female Human Papillomavirus Infection Associated with Increased Risk of Ectopic Pregnancy: Early Evidence from Taiwan Population-Based Cohort Study
Authors: Hsu Li-Chuan , Tu Ting-Yu , Chen Hui-Yuan , Chang Renin , Yip Hei-Tung , Chou Mei-Chia , Wei James Cheng-Chung , Tsui Kuan-Hao , Sheu Jim Jinn-Chyuan
Published: January 2022

Background: This is an investigation of the human papillomavirus (HPV) infection and its correlation with the risk of ectopic pregnancy (EP). Methods: The cohort study includes 11,239 patients with newly diagnosed HPV infections between 2000 and 2012, and by using computer-generated random numbers, patients who do not have HPV infections are selected randomly as the comparison cohort. The HPV infection cohort is matched to comparison individuals at a 1:10 ratio by age and index year. All individuals included in the study were followed up to the point they developed EP, pulled-out from the insurance program, lost to follow-up, or until the end of 2013. A Cox proportional-hazards regression analysis was used to analyze the risk of EP with the hazard ratios (HRs) and 95% confidence intervals (CIs) between the HPV and control cohort. Results: The adjusted hazard ratio (aHR) of EP for HPV patients relative to controls is 1.70 (95% CI = 1.04, 2.78), indicating a positive correlation between EP and HPV in the 13-year follow-up period, after adjusting for age and relevant comorbidities. The sensitivity analyses yield similar results. Conclusions: A history of HPV infection is a potential risk factor associated with the development of subsequent EP in Taiwanese individuals, especially those diagnosed with an HPV infection within 3 years.
Dealing with Corticosteroid and High-Dose Cyclosporine Therapy in a Pyoderma Gangrenosum Patient Contracting a COVID-19 Infection
Authors: May Marcella Ricardis , Rübben Albert , Lennertz Andrea , Vanstreels Luk , Leijs Marike
Published: January 2022

Pyoderma gangrenosum (PG) is a rare and chronic neutrophil inflammation belonging to the spectrum of autoinflammatory disorders. Immunosuppressive therapy is the cornerstone of successful treatment. However, due to the global COVID-19 pandemic, physicians struggle with therapeutic strategies during infection. This paper describes the case of a 58-year-old patient with a very painful, rapidly increasing wound on his right foot, which was diagnosed as pyoderma gangrenosum. Five weeks after the initial treatment with high-dose immunosuppressives (combination therapy with cyclosporine A and systemic methylprednisolone), he became infected with COVID-19. Reduction in the immunosuppressive dosage proved effective, as the patient recovered from COVID-19 without any complication and showed rapid wound healing.
Computational Genomics in the Era of Precision Medicine: Applications to Variant Analysis and Gene Therapy
Authors: Wang Yung-Chun , Wu Yuchang , Choi Julie , Allington Garrett , Zhao Shujuan , Khanfar Mariam , Yang Kuangying , Fu Po-Ying , Wrubel Max , Yu Xiaobing , Mekbib Kedous Y. , Ocken Jack , Smith Hannah , Shohfi John , Kahle Kristopher T. , Lu Qiongshi , Jin Sheng Chih
Published: January 2022

Rapid methodological advances in statistical and computational genomics have enabled researchers to better identify and interpret both rare and common variants responsible for complex human diseases. As we continue to see an expansion of these advances in the field, it is now imperative for researchers to understand the resources and methodologies available for various data types and study designs. In this review, we provide an overview of recent methods for identifying rare and common variants and understanding their roles in disease etiology. Additionally, we discuss the strategy, challenge, and promise of gene therapy. As computational and statistical approaches continue to improve, we will have an opportunity to translate human genetic findings into personalized health care.
Tourists’ Preferences for Stargazing Land Resources
Authors: Fernández-Hernández Carlos , Araña Jorge E. , de León Javier , León Carmelo J.
Published: January 2022

Stargazing tourism is an expanding market niche that requires the development of territorial resources for its implementation and attraction. This paper’s objective is to investigate the preferences and willingness to pay of tourists for the development of strategic land resources for stargazing tourism activities. The field work was conducted on the island of La Palma (Canary Islands), which is promoting the territorial development of infrastructures for stargazing tourism. A random sample of 734 tourists were interviewed in person on-site in December 2019 following the methodology discrete choice experiments that enabled an estimation of tourists’ preferences and willingness to pay for the implementation of key land resources for stargazing. The data are modeled using a latent class model that allows for the consideration of heterogeneous preferences. The results show that there are three groups of tourists with different preferences for land resources of stargazing observation. These segments are respectively related to the interests in culture, active, and astronomic tourism. Those tourists in the active stargazing segment share the largest proportion of the market and favor the implementation of facilities that allow the combination of active tourism with stargazing. The results are useful for land product development and territorial strategies aimed at positioning destinations in the identified demand niches of stargazing tourism.
Preparation of Human Milk Fat Substitutes: A Review
Authors: Jiang Xuan , Zou Xiaoqiang , Chao Zhonghao , Xu Xiuli
Published: January 2022

Human milk is generally regarded as the best choice for infant feeding. Human milk fat (HMF) is one of the most complex natural lipids, with a unique fatty acid composition and distribution and complex lipid composition. Lipid intake in infants not only affects their energy intake but also affects their metabolic mode and overall development. Infant formula is the best substitute for human milk when breastfeeding is not possible. As the main energy source in infant formula, human milk fat substitutes (HMFSs) should have a composition similar to that of HMF in order to meet the nutritional needs of infant growth and development. At present, HMFS preparation mainly focuses on the simulation of fatty acid composition, the application of structured lipids and the addition of milk fat globule membrane (MFGM) supplements. This paper first reviews the composition and structure of HMF, and then the preparation development of structured lipids and MFGM supplements are summarized. Additionally, the evaluation and regulation of HMFSs in infant formula are also presented.
Mitragyna Species as Pharmacological Agents: From Abuse to Promising Pharmaceutical Products
Authors: Ahmad Islamudin , Prabowo Wisnu Cahyo , Arifuddin Muhammad , Fadraersada Jaka , Indriyanti Niken , Herman Herman , Purwoko Reza Yuridian , Nainu Firzan , Rahmadi Anton , Paramita Swandari , Kuncoro Hadi , Mita Nur , Narsa Angga Cipta , Prasetya Fajar , Ibrahim Arsyik , Rijai Laode , Alam Gemini , Mun’im Abdul , Dej-adisai Sukanya
Published: January 2022

Mitragyna is a genus belonging to the Rubiaceae family and is a plant endemic to Asia and Africa. Traditionally, the plants of this genus were used by local people to treat some diseases from generation to generation. Mitragyna speciosa (Korth.) Havil. is a controversial plant from this genus, known under the trading name “kratom”, and contains more than 40 different types of alkaloids. Mitragynine and 7-hydroxymitragynine have agonist morphine-like effects on opioid receptors. Globally, Mitragyna plants have high economic value. However, regulations regarding the circulation and use of these commodities vary in several countries around the world. This review article aims to comprehensively examine Mitragyna plants (mainly M. speciosa) as potential pharmacological agents by looking at various aspects of the plants. A literature search was performed and information collected using electronic databases including Scopus, ScienceDirect, PubMed, directory open access journal (DOAJ), and Google Scholar in early 2020 to mid-2021. This narrative review highlights some aspects of this genus, including historical background and botanical origins, habitat, cultivation, its use in traditional medicine, phytochemistry, pharmacology and toxicity, abuse and addiction, legal issues, and the potential of Mitragyna species as pharmaceutical products.
Exceptional Thermoelectric Properties of Bilayer GeSe: First Principles Calculation
Authors: Fan Qiang , Zhang Weibin , Qing Haiyin , Yang Jianhui
Published: January 2022

The geometry structures, vibrational, electronic, and thermoelectric properties of bilayer GeSe, bilayer SnSe, and van der Waals (vdW) heterostructure GeSe/SnSe are investigated by combining the first-principles calculations and semiclassical Boltzmann transport theory. The dynamical stability of the considered structures are discussed with phonon dispersion. The phonon spectra indicate that the bilayer SnSe is a dynamically unstable structure, while the bilayer GeSe and vdW heterostructure GeSe/SnSe are stable. Then, the electronic structures for the bilayer GeSe and vdW heterostructure GeSe/SnSe are calculated with HSE06 functional. The results of electronic structures show that the bilayer GeSe and vdW heterostructure GeSe/SnSe are indirect band gap semiconductors with band gaps of 1.23 eV and 1.07 eV, respectively. The thermoelectric properties, including electrical conductivity, thermal conductivity, Seebeck coefficient, power factor, and figure of merit (ZT) are calculated with semiclassical Boltzmann transport equations (BTE). The results show that the n-type bilayer GeSe is a promising thermoelectric material.
Utilization of Calcium Carbide Residue as Solid Alkali for Preparing Fly Ash-Based Geopolymers: Dependence of Compressive Strength and Microstructure on Calcium Carbide Residue, Water Content and Curing Temperature
Authors: Wang Qiang , Guo Haozhe , Yu Ting , Yuan Peng , Deng Liangliang , Zhang Baifa
Published: January 2022

Calcium carbide residue (CCR) is a solid waste resulting from acetylene gas production. In this study, CCR was used as an alkali activator to prepare fly ash (FA)-based geopolymers without any alkali supplementation. We studied the factors (FA/CCR ratio, curing temperature, and water/binder ratio) influencing the mechanical property of FA/CCR-based geopolymers. The compressive strength results showed that, by optimizing these three factors, the FA/CCR mixture has great potential for use as a cementitious material and geopolymer with a dense microstructure having a maximal compressive strength of 17.5 MPa. The geopolymers’ chemical structure, microstructure, and chemical composition were characterized and determined by a combination of techniques. All these results revealed that amorphous C-(A)-S-H (calcium (aluminate) silicate hydrate) gels mainly formed after geopolymerization resulting from the reaction of FA and CCR. In addition, some crystallines, such as ettringite and monosulfate, were also formed. Further, geopolymers prepared with a suitable FA/CCR ratio (1:1 or 1:2) possessed a compact microstructure because of their sufficient reactive SiO2 and Al2O3 and high-enough alkalinity, responsible for higher content of C-(A)-S-H formation and better mechanical property. Too high curing temperature or water content induced the formation of a loosely bound geopolymer matrix that strongly weakens its mechanical property.
Counter-Intuitive Magneto-Water-Wetting Effect to CO2 Adsorption at Room Temperature Using MgO/Mg(OH)2 Nanocomposites
Authors: Senevirathna Hasanthi L. , Weerasinghe P. Vishakha T. , Li Xu , Tan Ming-Yan , Kim Sang-Sub , Wu Ping
Published: January 2022

MgO/Mg(OH)2-based materials have been intensively explored for CO2 adsorption due to their high theoretical but low practical CO2 capture efficiency. Our previous study on the effect of H2O wetting on CO2 adsorption in MgO/Mg(OH)2 nanostructures found that the presence of H2O molecules significantly increases (decreases) CO2 adsorption on the MgO (Mg(OH)2) surface. Furthermore, the magneto-water-wetting technique is used to improve the CO2 capture efficiency of various nanofluids by increasing the mass transfer efficiency of nanobeads. However, the influence of magneto-wetting to the CO2 adsorption at nanobead surfaces remains unknown. The effect of magneto-water-wetting on CO2 adsorption on MgO/Mg(OH)2 nanocomposites was investigated experimentally in this study. Contrary to popular belief, magneto-water-wetting does not always increase CO2 adsorption; in fact, if Mg(OH)2 dominates in the nanocomposite, it can actually decrease CO2 adsorption. As a result of our structural research, we hypothesized that the creation of a thin H2O layer between nanograins prevents CO2 from flowing through, hence slowing down CO2 adsorption during the carbon-hydration aging process. Finally, the magneto-water-wetting technique can be used to control the carbon-hydration process and uncover both novel insights and discoveries of CO2 capture from air at room temperature to guide the design and development of ferrofluid devices for biomedical and energy applications.
Promoters for Improved Adhesion Strength between Addition-Cured Liquid Silicone Rubber and Low-Melting-Point Thermoplastic Polyurethanes
Authors: Wu Jia-Kai , Zheng Kai-Wen , Nie Xing-Cheng , Ge Huang-Rong , Wang Qiong-Yan , Xu Jun-Ting
Published: January 2022

A polydimethylsiloxane armed with epoxy, alkoxy and acrylate groups was synthesized from silanol terminated-PDMS and epoxy and acrylate groups functionalized silane coupling agents, and utilized as the adhesion promoter (AP) to prepare addition-cured liquid silicone rubber that exhibited self-adhesion ability (SA-LSR) with biocompatible thermoplastic polyurethanes (TPU) sheets. The structural characteristics of AP were characterized by Fourier transform infrared (FTIR) spectroscopy, which demonstrated the strong adhesion to polyester-based TPU sheets due to a sufficient amount of acrylate groups, epoxy groups and silanol groups obtained by the hydrolysis of alkoxy groups. In detail, the peel-off strength of SA-LSR and TPU joints reached up to 7.63 N mm−1 after the optimization of adhesion promoter including type and content, and curing condition including time and temperature. The cohesive failure was achieved during the sample breakage process. Moreover, the SA-LSR showed a good storage stability under proper storage conditions. This design strategy provided the feasibility to combine the advantages of addition-cured liquid silicone rubber and plastics with low melting points, promoting the potential application range of those silicone-based materials.
Effective Approximation Method for Nanogratings-induced Near-Field Radiative Heat Transfer
Authors: Liu Yang , Chen Fangqi , Caratenuto Andrew , Tian Yanpei , Liu Xiaojie , Zhao Yitong , Zheng Yi
Published: January 2022

Nanoscale radiative thermal transport between a pair of metamaterial gratings is studied within this work. The effective medium theory (EMT), a traditional method to calculate the near-field radiative heat transfer (NFRHT) between nanograting structures, does not account for the surface pattern effects of nanostructures. Here, we introduce the effective approximation NFRHT method that considers the effects of surface patterns on the NFRHT. Meanwhile, we calculate the heat flux between a pair of silica (SiO2) nanogratings with various separation distances, lateral displacements, and grating heights with respect to one another. Numerical calculations show that when compared with the EMT method, here the effective approximation method is more suitable for analyzing the NFRHT between a pair of relatively displaced nanogratings. Furthermore, it is demonstrated that compared with the result based on the EMT method, it is possible to realize an inverse heat flux trend with respect to the nanograting height between nanogratings without modifying the vacuum gap calculated by this effective approximation NFRHT method, which verifies that the NFRHT between the side faces of gratings greatly affects the NFRHT between a pair of nanogratings. By taking advantage of this effective approximation NFRHT method, the NFRHT in complex micro/nano-electromechanical devices can be accurately predicted and analyzed.
Corrosion Behavior of Ultrafine-Grained CoCrFeMnNi High-Entropy Alloys Fabricated by High-Pressure Torsion
Authors: Shimizu Haruka , Yuasa Motohiro , Miyamoto Hiroyuki , Edalati Kaveh
Published: January 2022

The influence of the nanocrystalline structure produced by severe plastic deformation (SPD) on the corrosion behavior of CoCrFeMnNi alloys with Cr contents ranging from 0 to 20 at.% was investigated in aqueous 0.5 M H2SO4 and 3.5% NaCl solutions. The resistance to general corrosion and pitting became higher in both the solutions, with higher passivation capability observed with increasing Cr content, and it is believed that the high corrosion resistance of CoCrFeMnNi alloys can be attributed to the incorporation of the Cr element. However, the impact of the nanocrystalline structure produced by SPD on the corrosion behavior was negligibly small. This is inconsistent with reports on nanocrystalline binary Fe–Cr alloys and stainless steels processed by SPD, where grain refinement by SPD results in higher corrosion resistance. The small change in the corrosion behavior with respect to grain refinement is discussed, based on the passivation process of Fe–Cr alloys and on the influence of the core effects of HEAs on the passivation process.
K2O-Metakaolin-Based Geopolymer Foams: Production, Porosity Characterization and Permeability Test
Authors: Papa Elettra , Landi Elena , Miccio Francesco , Medri Valentina
Published: January 2022

In this paper, four near-net shaped foams were produced via direct foaming, starting from a benchmark metakaolin-based geopolymer formulation. Hydrogen peroxide and metallic silicon were used in different amounts as blowing agents to change the porosity from meso- to ultra-macro-porosity. Foams were characterized by bulk densities ranging from 0.34 to 0.66 g cm−3, total porosity from 70% to 84%, accessible porosity from 41% to 52% and specific surface area from 47 to 94 m2 g−1. Gas permeability tests were performed, showing a correlation between the pore features and the processing methods applied. The permeability coefficients k1 (Darcian) and k2 (non-Darcian), calculated applying Forchheimer’s equation, were higher by a few orders of magnitude for the foams made using H2O2 than those made with metallic silicon, highlighting the differing flow resistance according to the interconnected porosity. The gas permeability data indicated that the different geopolymer foams, obtained via direct foaming, performed similarly to other porous materials such as granular beds, fibrous filters and gel-cast foams, indicating the possibility of their use in a broad spectrum of applications.
Evaluation of the Approach for the Identification of Trajectory Anomalies on CCTV Video from Road Intersections
Authors: Minnikhanov Rifkat , Anikin Igor , Mardanova Aigul , Dagaeva Maria , Makhmutova Alisa , Kadyrov Azat
Published: January 2022

The approach for the detection of vehicle trajectory abnormalities on CCTV video from road intersections was proposed and evaluated. We mainly focused on the trajectory analysis method rather than objects detection and tracking. Two basic challenges have been overcome in the suggested approach—spatial perspective on the image and performance. We used trajectory approximation by polynomials as well as the Ramer-Douglas-Peucker N thinning technique to increase the performance of the trajectory comparison method. Special modification of trajectory similarity metric LCSS was suggested to consider the spatial perspective. We used clustering to discover two types of classes—with normal and abnormal trajectories. The framework, which implements the suggested approach, was developed. A series of experiments were carried out for testing the approach and defining recommendations for using different techniques in the scope of it.
Targeted Allocation of Marketing Resource in Networks Based on Opinion Dynamics
Authors: Lang Ningning , Wang Lin , Zha Quanbo
Published: January 2022

Recent advances in information technology and the boom in social media provide firms with easy access to the data of consumers’ preferences and their social interactions. To characterize marketing resource allocation in networks, this paper develops a game theoretical model that allows for each firm’s own utility, action strategies of other firms and the inner state (self-belief and opinions) of consumers. In this model, firms can sway consumers’ opinions by spending marketing resources among consumers under budget and cost constraints. Each firm competes for the collective preference of consumers in a social network to maximize its utility. We derived the equilibrium strategies theoretically in a connected network and a dispersed network from the constructed model. These reveal that firms should allocate more marketing resources to some of consumers depending on their initial opinions, self-belief and positions in a network. We found that some structures of consumer networks may have an innate dominance for one firm, which can be retained in equilibrium results. This means that network structure can be as a tool for firms to improve their utilities. Furthermore, the sensitivities of budget and cost to the equilibria were analyzed. These results can provide some reference for resource allocation strategies in marketing competition.
Anticipated Backward Doubly Stochastic Differential Equations with Non-Lipschitz Coefficients
Authors: Wang Tie , Cui Siyu
Published: January 2022

The work presented in this paper focuses on a type of differential equations called anticipated backward doubly stochastic differential equations (ABDSDEs) whose generators not only depend on the anticipated terms of the solution (Y·,Z·) but also satisfy one kind of non-Lipschitz assumption. Firstly, we give the existence and uniqueness theorem. Further, two comparison theorems for the solutions of these equations are obtained after finding a new comparison theorem for backward doubly stochastic differential equations (BDSDEs) with non-Lipschitz coefficients.
The Generalized First- and Second-Price Auctions: Overbidding, Underbidding, and Optimal Reserve Price
Authors: Tan Ziyi , Liu Shulin
Published: January 2022

The paper generalizes the models of the standard first- and second-price auctions (FPA and SPA) by using the Cobb-Douglas function to evaluate bidders’ two conflicting bidding preferences for the probability of winning the item (Cpwin) and the profit conditional on winning (Cprofit). Compared with the popular expected profit function, this function has the advantage of allowing the bidders to equally or differently value Cpwin and Cprofit from the point of view of multiple criteria decision making, and then can capture bidders’ bidding behavior in reality. Introduction of the Cobb-Douglas function into the FPA allows us to provide new interpretations for overbidding (underbidding) behavior and the dependence of the optimal reserve price on the number of bidders. Our new interpretations are all attributed to the bidders’ different preferences for Cpwin and Cprofit. In contrast, this introduction into the SPA does not matter. Our findings suggest that the seller should prefer the FPA (SPA) over the SPA (FPA) and set a lower (higher) optimal reserve price if he conjectures that the bidders have a stronger desire to win an auction (to obtain a profit). The above results help the seller to select between the two auctions and set a reserve price in practice.
Improving Facial Emotion Recognition Using Residual Autoencoder Coupled Affinity Based Overlapping Reduction
Authors: Chatterjee Sankhadeep , Das Asit Kumar , Nayak Janmenjoy , Pelusi Danilo
Published: January 2022

Emotion recognition using facial images has been a challenging task in computer vision. Recent advancements in deep learning has helped in achieving better results. Studies have pointed out that multiple facial expressions may present in facial images of a particular type of emotion. Thus, facial images of a category of emotion may have similarity to other categories of facial images, leading towards overlapping of classes in feature space. The problem of class overlapping has been studied primarily in the context of imbalanced classes. Few studies have considered imbalanced facial emotion recognition. However, to the authors’ best knowledge, no study has been found on the effects of overlapped classes on emotion recognition. Motivated by this, in the current study, an affinity-based overlap reduction technique (AFORET) has been proposed to deal with the overlapped class problem in facial emotion recognition. Firstly, a residual variational autoencoder (RVA) model has been used to transform the facial images to a latent vector form. Next, the proposed AFORET method has been applied on these overlapped latent vectors to reduce the overlapping between classes. The proposed method has been validated by training and testing various well known classifiers and comparing their performance in terms of a well known set of performance indicators. In addition, the proposed AFORET method is compared with already existing overlap reduction techniques, such as the OSM, ν-SVM, and NBU methods. Experimental results have shown that the proposed AFORET algorithm, when used with the RVA model, boosts classifier performance to a greater extent in predicting human emotion using facial images.
Characterization of Automorphisms of (θ,ω)-Twisted Radford’s Hom-Biproduct
Authors: Wang Xing , Wang Ding-Guo
Published: January 2022

In this paper, we study the Hom–Hopf algebra automorphism group of a (θ,ω)-twisted-Radford’s Hom-biproduct, which satisfies certain conditions. First, we study the endomorphism monoid and automorphism group of (θ,ω)-twisted Radford’s Hom-biproducts, and show that the endomorphism has a factorization closely related to the factors (A,α) and (H,β). Then, we consider (θ,ω)-twisted Radford’s Hom-biproduct automorphism group AutHom-Hopf(A×ωθH,p) as a subgroup of some semidirect product U(C,A)op⋊φG(A). Finally, we characterize the automorphisms of a concrete example.
A Dynamic Analysis of Randomly Oriented Functionally Graded Carbon Nanotubes/Fiber-Reinforced Composite Laminated Shells with Different Geometries
Authors: Melaibari Ammar , Daikh Ahmed Amine , Basha Muhammad , Wagih Ahmed , Othman Ramzi , Almitani Khalid H. , Hamed Mostafa A. , Abdelrahman Alaa , Eltaher Mohamed A.
Published: January 2022

The present study demonstrates the free vibration behavior of composite laminated shells reinforced by both randomly oriented single-walled carbon nanotubes (SWCNTs) and functionally graded fibers. The shell structures with different principal radii of curvature are considered, such as cylindrical, spherical, elliptical–paraboloid shell, hyperbolic–paraboloid shell, and plate. The volume fraction of the fibers has a linear variation along the shell thickness from layer to layer, while the volume fraction of CNTs is constant in all shell layers and uniformly distributed. The fiber-reinforced elements are distributed with three functions which are V-distribution, O-distribution, and X-distribution in addition to the uniform distribution. A numerical analysis was carried out systematically to validate the proposed solution. A new analytical solution is presented based on the Galerkin approach for shells and is exploited to illustrate the influence of some factors on the free vibration behavior of CNTs/fibe-reinforced composite (CNTs/F-RC) laminated shells, including the distributions and volume fractions, various boundary conditions, and geometrical properties of the reinforcement materials. The proposed solution is shown to be an effective theoretical tool to analyze the free vibration response of shells.
Initial-Condition Effects on a Two-Memristor-Based Jerk System
Authors: Bao Han , Ding Ruoyu , Hua Mengjie , Wu Huagan , Chen Bei
Published: January 2022

Memristor-based systems can exhibit the phenomenon of extreme multi-stability, which results in the coexistence of infinitely many attractors. However, most of the recently published literature focuses on the extreme multi-stability related to memristor initial conditions rather than non-memristor initial conditions. In this paper, we present a new five-dimensional (5-D) two-memristor-based jerk (TMJ) system and study complex dynamical effects induced by memristor and non-memristor initial conditions therein. Using multiple numerical methods, coupling-coefficient-reliant dynamical behaviors under different memristor initial conditions are disclosed, and the dynamical effects of the memristor initial conditions under different non-memristor initial conditions are revealed. The numerical results show that the dynamical behaviors of the 5-D TMJ system are not only dependent on the coupling coefficients, but also dependent on the memristor and non-memristor initial conditions. In addition, with the analog and digital implementations of the 5-D TMJ system, PSIM circuit simulations and microcontroller-based hardware experiments validate the numerical results.
Vitamin D Implications and Effect of Supplementation in Endocrine Disorders: Autoimmune Thyroid Disorders (Hashimoto’s Disease and Grave’s Disease), Diabetes Mellitus and Obesity
Authors: Galușca Dorina , Popoviciu Mihaela , Babeș Emilia , Vidican Mădălina , Zaha Andreea , Babeș Vlad , Jurca Alexandru , Zaha Dana , Bodog Florian
Published: January 2022

Background and Objectives: Vitamin D deficiency is involved in numerous pathologies, including endocrine pathology. The purpose of this review consists of presenting the role of vitamin D in the pathophysiology of certain endocrine disorders, autoimmune thyroid disorders (Hashimoto’s disease and Grave’s disease), diabetes mellitus, and obesity, and whether its supplementation can influence the outcome of these diseases. Materials and Methods: Review articles and original articles from the literature were consulted that corresponded with the thematic. Results: Vitamin D deficiency is frequently encountered in endocrine disorders and supplementation restores the normal values. In Hashimoto’s disease, vitamin D deficiency appears to be correlated with a higher titer of anti-TPO antibodies and with thyroid volume, and supplementation was associated with reduction of antibodies in some studies. In other studies, supplementation appeared to reduce TSH levels. In Grave’s disease, there was a significant correlation regarding vitamin D levels and thyroid volume respective to the degree of exophthalmos. In diabetes mellitus type 2 patients, supplementation led to some improvement of the HOMA-IR index and HbA1c, whereas obesity data from literature do not report significant beneficial findings. Conclusions: Vitamin D deficiency is highly prevalent in endocrine disorders and its supplementation appears to have numerous beneficial effects.
Soft Tissue Sarcomas: A 16-Year Experience of a Tertiary Referral Hospital in North Jordan
Authors: Alorjani Mohammed S. , Matalka Ismail I. , Alfaqih Mahmoud A. , Jahmani Rami A. , Alsinglawi Belal S. , Nimri Faisal M. , Matalka Mohammad I. , Amr Samir S.
Published: January 2022

Background and Objectives: Sarcomas are rare malignant tumors of mesenchymal origin. Their low prevalence and histological heterogeneity make their diagnosis a challenging task. To the best of our knowledge, the epidemiology of soft tissue sarcomas (STSs) was not well studied in Jordan. This study thus aimed to determine STS epidemiologic trends at King Abdullah University Hospital (KAUH); a tertiary hospital that provides cancer healthcare for 70% of the population in Irbid Governorate, North Jordan. The findings of this study will provide a good reference point of the burden of STSs in Jordan and the Middle East region. Materials and Methods: All cases with confirmed STS diagnoses who attended KAUH from January 2003 until December 2018 were included in the initial analysis. Bone sarcomas, gastrointestinal stromal tumors and uterine sarcomas were not included in the study. Information collected from the pathology reports and electronic medical records was used to determine STS prevalence, incidence rate, age and gender distributions, histological types and anatomic location. Cases were reviewed by three pathologists with interest in soft tissue tumors. The findings were compared with literature. Results: In total, 157 STS cases were reported (1.9% of cancers diagnosed at KAUH during the 16-year study period). Crude annual incidence rate (IR) per 100,000 person-years ranged from 0.48 in 2015 to 1.83 in 2011 (average = 1.04). Age-standardized IR (ASR)(World WHO 2000–2025) was 1.37. Male:female ratio was 1.3:1. Median age was 39 years. Age ranged from <1 year to 90 years. Overall STS rates increased with age. The most common histological types were liposarcoma (19%), rhabdomyosarcoma (17%) and leiomyosarcoma (10%). The most common anatomic location was the extremity (40.1%), followed by the trunk (14.7%), then head and neck (10.8%). Conclusion: STSs are rare in North Jordan. A slight increase in their incidence was identified during the study period similar to global trends. The collection of relevant data on established risk factors along with a broader scale evaluation of the epidemiology of STS in the Middle East region is recommended to better evaluate disease burden and trends.
Homo Sapiens (Hsa)-microRNA (miR)-6727-5p Contributes to the Impact of High-Density Lipoproteins on Fibroblast Wound Healing In Vitro
Authors: Bastaki Khaled Mahmoud , Tarlton Jamie Maurice Roy , Lightbody Richard James , Graham Annette , Martin Patricia Esther
Published: January 2022

Chronic, non-healing wounds are a significant cause of global morbidity and mortality, and strategies to improve delayed wound closure represent an unmet clinical need. High-density lipoproteins (HDL) can enhance wound healing, but exploitation of this finding is challenging due to the complexity and instability of these heterogeneous lipoproteins. The responsiveness of primary human neonatal keratinocytes, and neonatal and human dermal fibroblasts (HDF) to HDL was confirmed by cholesterol efflux, but promotion of ‘scrape’ wound healing occurred only in primary human neonatal (HDFn) and adult fibroblasts (HDFa). Treatment of human fibroblasts with HDL induced multiple changes in the expression of small non-coding microRNA sequences, determined by microchip array, including hsa-miR-6727-5p. Intriguingly, levels of hsa-miR-6727-5p increased in HDFn, but decreased in HDFa, after exposure to HDL. Delivery of a hsa-miR-6727-5p mimic elicited repression of different target genes in HDFn (ZNF584) and HDFa (EDEM3, KRAS), and promoted wound closure in HDFn. By contrast, a hsa-miR-6727-5p inhibitor promoted wound closure in HDFa. We conclude that HDL treatment exerts distinct effects on the expression of hsa-miR-6727-5p in neonatal and adult fibroblasts, and that this is a sequence which plays differential roles in wound healing in these cell types, but cannot replicate the myriad effects of HDL.
Highly Selective and pH-Stable Reverse Osmosis Membranes Prepared via Layered Interfacial Polymerization
Authors: Shin Min-Gyu , Choi Wansuk , Lee Jung-Hyun
Published: January 2022

Ultrathin and smooth polyamide (PA) reverse osmosis (RO) membranes have attracted significant interest due to their potential advantages of high permeance and low fouling propensity. Although a layered interfacial polymerization (LIP) technique aided by the insertion of a polyelectrolyte interlayer has proven effective in fabricating ultrathin and uniform membranes, the RO performance and pH stability of the fabricated LIP membrane remain inadequate. In this study, a poly(piperazineamide) (PIPA) layer prepared via interfacial polymerization (IP) was employed as an interlayer to overcome the limitations of the prototype LIP method. Similar to the control polyelectrolyte-interlayered LIP membrane, the PIPA-interlayered LIP (pLIP) membrane had a much thinner (~20 nm) and smoother selective layer than the membrane fabricated via conventional IP due to the highly surface-confined and uniform LIP reaction. The pLIP membrane also exhibited RO performance exceeding that of the control LIP and conventional IP-assembled membranes, by enabling denser monomer deposition and a more confined interfacial reaction. Importantly, the chemically crosslinked PIPA interlayer endowed the pLIP membrane with higher pH stability than the control polyelectrolyte interlayer. The proposed strategy enables the fabrication of high-performance and pH-stable PA membranes using hydrophilic supports, which can be applied to other separation processes, including osmosis-driven separation and organic solvent filtration.
Derivation of the Coefficients in the Coulomb Constant Shear Friction Law from Experimental Data on the Extrusion of a Material into V-Shaped Channels with Different Convergence Angles: New Method and Algorithm
Authors: Bobrovskij Igor , Khaimovich Alexander , Bobrovskij Nikolaj , Travieso-Rodriguez J. Antonio , Grechnikov Fedor
Published: January 2022

The combined Coulomb constant shear friction law is widely used in commercial and research software for the finite-element analysis (FEA) of metalworking and is naturally more flexible and hence, more relevant to real-life manufacturing than the individual Coulomb and constant shear friction laws. In this work, a new mathematical model of coefficients in the Coulomb constant shear friction law for extruding a metal through narrow V-shaped channels with small convergence angles has been developed and evaluated and compared with laboratory measurements. The extrusion of the model material (lead) through narrow V-shaped channels with small convergence angles varying from 0 to 3.5 degrees has been studied. The Coulomb friction coefficient µ and the constant friction factor m appear to be independent of the dimension ratio and are influenced mostly by roughness and range from µ = 0.363 (with lubricant) to µ = 0.488 (without lubricant) and from m = 0.726 (with lubricant) to 0.99 (without lubricant). The relative length dominated by the Coulomb friction law is less than 1%, and the Coulomb’s coefficient of friction can be approximated as ½ the constant shear friction factor for all tested cases. The developed method and algorithm can be used in both FEA of manufacturing processes and efficiency tests for lubricants used in metalworking.
A Prospective Way to Achieve Ballistic Impact Resistance of Lightweight Magnesium Alloys
Authors: Malik Abdul , Nazeer Faisal , Wang Yangwei
Published: January 2022

The ballistic impact resistance of lightweight magnesium alloys is an eye-catching material for the military and aerospace industries, which can decrease the cost of a project and the fuel consumption. The shockwave mitigation ability of a magnesium alloy is 100 times stronger than an aluminum alloy; nonetheless, ballistic impact resistance has still not been achieved against blunt and API projectiles. The major obstacles are the low hardness, low mechanical strength, basal texture and strain hardening ability under loading along the normal direction of the sheet. The high yield strength and ultimate strength can be achieved for a specific loading condition (tensile or compression) by adjusting the texture in magnesium alloys. The projectile impact along the normal direction in a strong basal-textured magnesium alloy can only produce a slip-induced deformation or minor twinning activity. Here, we propose a practical technique that can be valuable for altering the texture from c-axes//ND to c-axes//ED or TD, and can produce high strain hardening and high strength through a twinning and de-twinning activity. Subsequently, it can improve the ballistic impact resistance of magnesium alloys. The effect of the technique on the evolution of the microstructure and possible anticipated deformation mechanisms after ballistic impact is proposed and discussed.
Influence of Inclusions on Mechanical Properties in Flash Butt Welding Joint of High-Strength Low-Alloy Steel
Authors: Shi Shih-Chen , Wang Wei-Cheng , Ko Dun-Kai
Published: January 2022

Flash butt welding is a high-efficiency welding technology that is widely used in industrial development. However, the inclusions and defects generated during the process are unacceptable. The presence of inclusions is one of the main factors affecting the quality of flash butt welding. Suitable flash butt welding parameters such as the preheating temperature and upset distance are essential to eliminate inclusions. In this study, because the number of inclusions on the end face is greatly affected by the flash welding time and upset distance, the impact of different upset distances on the number of inclusions was studied by fixing the flash welding time. Further observations were conducted using a scanning electron microscope. Image analysis software was used on the obtained photos to quantitatively analyze the inclusions on the welding surface. A statistical analysis of the experimental data showed that the upset distance was related to the number of inclusions, and the total number of inclusions on the welding surface had a negative impact on the strength of the product.
Effect of Ti Addition on the Precipitation Mechanism and Precipitate Size in Nb-Microalloyed Steels
Authors: Xing Jun , Zhu Guohui , Wu Baoqiao , Ding Hanlin , Pan Hongbo
Published: January 2022

The effect of Ti microalloying on the precipitation of NbC particles in Nb-microalloyed and Nb-Ti-microalloyed steels was investigated by scanning transmission electron microscopy. The experimental results illustrate that NbC precipitates tend to be formed via a conventional “nucleation and growth” mechanism in Ti-free steel, while the particles would be precipitated as a complex form of TiN cuboid core and NbC hemispherical cap in Ti-Nb-microalloyed steel with 0.009 wt.% Ti and 0.0046 wt.% N. Ti microalloying contributed to the refinement of the precipitate size, and an enhancement of the volume fraction of NbC particles was also found based on the experimental observations.
Machinable Leaded and Eco-Friendly Brass Alloys for High Performance Manufacturing Processes: A Critical Review
Authors: Stavroulakis Paul , Toulfatzis Anagnostis I. , Pantazopoulos George A. , Paipetis Alkiviadis S.
Published: January 2022

The recent environmental/health and safety regulations placed restrictions of use of hazardous substances on critical manufacturing sectors and consumers’ products. Brass alloys specifically face a challenging issue concerning the elimination of lead (Pb) which has been a critical element affecting both the machinability and overall quality and efficiency of their manufacturing process. The adaptation of novel materials and processing routes in the green economy constitutes a crucial decision for competitive business and industry growth as a worldwide perspective with substantial industrial and social impact. This paper aims to review the emergent innovative and sustainable material solutions in the manufacturing industry, in line with environmental regulations, by highlighting smart alloy design practices and promoting new and innovative approaches for material selection and manufacturing process optimisation. In this review we analyse the processing, structure and machinability aspects of leaded brasses and underline the major guidelines and research methodologies required to overcome this technical challenge and further improve the mechanical properties and machinability of lead-free brass alloys. Various alloying and processing strategies were reviewed together with the most important failure types, as they were extracted from the existing industrial and technological experience, covering more than 20 years of research in this field.
Shape Memory Effect and Martensitic Transformation in Fe–Mn–Al–Ni Alloy
Authors: Zhang Rui , Sun Deshan , Ji Chunmeng , Chen Yulin , Zhang Xin , Dong Zhizhong
Published: January 2022

In this study, the influence of an aging treatment on the shape memory effect and martensitic transformation was investigated in an Fe–Mn–Al–Ni alloy by adding a small amount of Nb and C elements. Results show that the aging treatment can significantly improve the shape recovery rate of the alloy. In the bending test with 4% deformation, after aging at 200 °C for 1 h, the recovery rate increased from 20 to 45%, and it further increased to 51% after the two-step aging treatment at 800 and 200 °C. The high-temperature in situ X-ray diffraction and atomic force microscope were used to reveal the shape memory effect between room temperature and 400 °C in this alloy due to γ′→α transformation. The microstructure of aged specimens was investigated using transmission electron microscopy. With the extension of the aging time from 0.5 to 6 h, the size of NiAl precipitation gradually grew from 9 to 32 nm, and the distribution became more uniform. Meanwhile, the NbC particles were found in the two-step aging treatment alloy, which was the key to improving the shape memory effect.
Development of Antibiofilm Therapeutics Strategies to Overcome Antimicrobial Drug Resistance
Authors: Nadar Sahaya , Khan Tabassum , Patching Simon G. , Omri Abdelwahab
Published: January 2022

A biofilm is a community of stable microorganisms encapsulated in an extracellular matrix produced by themselves. Many types of microorganisms that are found on living hosts or in the environment can form biofilms. These include pathogenic bacteria that can serve as a reservoir for persistent infections, and are culpable for leading to a broad spectrum of chronic illnesses and emergence of antibiotic resistance making them difficult to be treated. The absence of biofilm-targeting antibiotics in the drug discovery pipeline indicates an unmet opportunity for designing new biofilm inhibitors as antimicrobial agents using various strategies and targeting distinct stages of biofilm formation. The strategies available to control biofilm formation include targeting the enzymes and proteins specific to the microorganism and those involved in the adhesion pathways leading to formation of resistant biofilms. This review primarily focuses on the recent strategies and advances responsible for identifying a myriad of antibiofilm agents and their mechanism of biofilm inhibition, including extracellular polymeric substance synthesis inhibitors, adhesion inhibitors, quorum sensing inhibitors, efflux pump inhibitors, and cyclic diguanylate inhibitors. Furthermore, we present the structure–activity relationships (SAR) of these agents, including recently discovered biofilm inhibitors, nature-derived bioactive scaffolds, synthetic small molecules, antimicrobial peptides, bioactive compounds isolated from fungi, non-proteinogenic amino acids and antibiotics. We hope to fuel interest and focus research efforts on the development of agents targeting the uniquely complex, physical and chemical heterogeneous biofilms through a multipronged approach and combinatorial therapeutics for a more effective control and management of biofilms across diseases.