bluuebunny/crossref_metadata_2025 huggingface dataset:
The Compliance of the Upper Critical Field in Magic-Angle Multilayer Graphene with the Pauli Limit
Authors: Talantsev Evgueni F.
Published: December 2022

The Pauli limiting field represents a fundamental magnetic field at which the superconducting state collapses due to the spin-paramagnetic Cooper pair-breaking effect. Cao et al. (Nature 2021, 595, 526) reported that the magic-angle twisted trilayer graphene (MATNG, N = 3) exhibits the upper critical field which exceeds the Pauli limiting field by two to three times. This observation was interpreted as a violation of the Pauli-limiting field in MAT3G. Similar conclusions were recently reported by the same research group in MATNG (N = 4, 5) superlattices (Park, J.M. et al. Nat. Mater.2022, 21, 877). Here, we point out that Cao et al. (Nature 2021, 595, 526) calculated the Pauli limiting field by the use of reduced form (to the weak-coupling limit) of full equation of the theory of the electron–phonon-mediated superconductivity. Considering that in the same paper, Cao et al. (Nature 2021, 595, 526) reported that MATNGs are strong coupled superconductors, we calculate the Pauli limiting field for a strong coupled case and show that the observed upper critical fields in MATNGs comply with the Pauli limit. This implies that there is no violation of the Pauli limiting field in the Moiré multilayer graphene superlattices.
Influence of Various Coal Energy Wastes and Foaming Agents on Foamed Geopolymer Materials’ Synthesis
Authors: Yatsenko Elena A. , Goltsman Boris M. , Trofimov Sergei V. , Novikov Yuri V. , Smoliy Victoria A. , Ryabova Anna V. , Klimova Lyudmila V.
Published: December 2022

The regularities of obtaining foamed alkali-activated geopolymer materials based on different wastes of coal power engineering (fly ash, fuel (boiler) slag, ash, and slag mixture) were considered. The phase composition of the studied waste showed the presence of a significant amount of the amorphous phase, as well as a crystalline phase. mostly in the form of high quartz. The microstructure of studied the waste showed that the fly ash consisted of monodisperse hollow aluminosilicate microspheres, the fuel slag was represented by polydisperse irregular particles, and the ash and slag mixture included both of these materials in different ratios. Blowing agents such as aluminum powder, hydrogen peroxide, and sodium hypochlorite were chosen to achieve the porous structure of the geopolymer materials. The calculations of the geopolymer precursor compositions were carried out. Samples were synthesized, and their physical and mechanical properties, such as density, strength, porosity, and thermal conductivity, were analyzed. The micro- and macrostructure of the samples, as well as the pore distribution of the obtained geopolymers were studied. Conclusions were made on the choice of the most-optimal foaming agent and the optimal coal combustion waste suitable for the synthesis of the geopolymer materials.
Assessment of Two Advanced Aluminium-Based Metal Matrix Composites for Application to High Energy Physics Detectors
Authors: Buchanan Katie Elizabeth , Sgobba Stefano , Celuch Michal Dalemir , Perez Gomez Francisco , Onnela Antti , Rose Pierre , Postema Hans , Pentella Mariano , Lacombe Guillaume , Thomas Benjamin , de Langlade Renaud , Paquin Yvan
Published: December 2022

The Outer Tracker of the Compact Muon Solenoid (CMS), one of the large experiments at the CERN Large Hadron Collider, will consist of about 13,200 modules, each built up of two silicon sensors. The modules and support structures include thousands of parts that contribute to positioning and cooling the sensors during operation at −30 °C. These parts should be low mass while featuring high thermal conductivity, stiffness and strength. Their thermal expansion coefficient should match that of silicon to avoid deformations during cooling cycles. Due to their unique thermal and mechanical properties, aluminium-carbon fibre (Al/Cf) Metal Matrix Composites are the material of choice to produce such light and stable thermal management components for High Energy Physics detectors. For the CMS Outer Tracker, about 500,000 cm3 of Al/Cf raw material will be required to be produced through a reliable process to guarantee consistent properties throughout parts manufacturing. Two Al/Cf production routes are currently considered: liquid casting by gas-pressure infiltration and a powder metallurgy process based on continuous semi-liquid phase sintering. The dimensional stability of the resulting material is of paramount importance. Irreversible change of shape may be induced by moisture adsorption and the onset of galvanic corrosion at the discontinuous interfaces between Cf and Al. This paper presents the results of an extensive investigation through Computed Microtomography, direct microscopical investigations, analysis of the interfaces and metrology measurements aimed at comparing and interpreting the response to different environments of the respective products. The results obtained confirm the suitability of the two investigated Al/Cf MMCs for application to components of the CMS Outer Tracker, requiring tight geometrical control and microstructural stability over time. However, for PM parts sintered through the semi-liquid phase process, a multilayered protective noble metal coating is necessary the make them impervious to moisture, allowing dimensional stability to be guaranteed and the onset of corrosion phenomena to be avoided, while the product obtained by gas-pressure infiltration has shown less sensitive even to extreme temperature-humidity cycles and may be used uncoated.
Facile Synthesis of Island-like ZrO2-VO2 Composite Films with Enhanced Thermochromic Performance for Smart Windows
Authors: Wu Jiahao , Wang Zhe , Li Bin , Liu Baoshun , Zhao Xiujian , Tang Gen , Zeng Dawen , Tian Shouqin
Published: December 2022

VO2-based film, as a very promising thermochromic material for smart windows, has attracted extensive attention but has not been widely applied because it is difficult to simultaneously improve in terms of both solar-modulation efficiency (ΔTsol) and visible transmittance (Tlum) when made using the magnetron-sputtering method, and it has poor durability when made using the wet chemical method. Herein, island-like ZrO2-VO2 composite films with improved thermochromic performance (ΔTsol: 12.6%, Tlum: 45.0%) were created using a simple approach combining a dual magnetron-sputtering and acid-solution procedure. The film’s ΔTsol and Tlum values were increased initially and subsequently declined as the sputtering power of the ZrO2 target was raised from 30 W to 120 W. ΔTsol achieved its maximum of 12.6% at 60 W, and Tlum reached its maximum of 51.1% at 90 W. This is likely the result of the interaction of two opposing effects: Some VO2 nanocrystals in the composite film were isolated by a few ZrO2 grains, and some pores could utilize their surface-plasmon-resonance effect at high temperature to absorb some near-infrared light for an enhanced ΔTsol and Tlum. More ZrO2 grains means fewer VO2 grains in the composite film and increased film thickness, which also results in a decrease in ΔTsol and Tlum. As a result, this work may offer a facile strategy to prepare VO2-based films with high thermochromic performance and promote their application in smart windows.
Active Food Packaging Made of Biopolymer-Based Composites
Authors: Hu Xuanjun , Lu Chao , Tang Howyn , Pouri Hossein , Joulin Etienne , Zhang Jin
Published: December 2022

Food packaging plays a vital role in protecting food products from environmental damage and preventing contamination from microorganisms. Conventional food packaging made of plastics produced from unrenewable fossil resources is hard to degrade and poses a negative impact on environmental sustainability. Natural biopolymers are attracting interest for reducing environmental problems to achieve a sustainable society, because of their abundance, biocompatibility, biodegradability, chemical stability, and non-toxicity. Active packaging systems composed of these biopolymers and biopolymer-based composites go beyond simply acting as a barrier to maintain food quality. This review provides a comprehensive overview of natural biopolymer materials used as matrices for food packaging. The antioxidant, water barrier, and oxygen barrier properties of these composites are compared and discussed. Furthermore, biopolymer-based composites integrated with antimicrobial agents—such as inorganic nanostructures and natural products—are reviewed, and the related mechanisms are discussed in terms of antimicrobial function. In summary, composites used for active food packaging systems can inhibit microbial growth and maintain food quality.
Study of Effect of Coil Movement on Growth Conditions of SiC Crystal
Authors: Zhang Shengtao , Fu Hao , Li Tie , Fan Guofeng , Zhao Lili
Published: December 2022

SiC substrates have outstanding advantages over traditional materials in power device application, and are mainly prepared by a physical vapor transport method (PVT). Whether the PVT furnace works by resistance heating or induction heating, both face the problem of the deterioration of growth conditions during a long-term process. The relative position of the thermal field directly affects the crystal growth conditions, but the law of specific influence and the change in physical environment inside the thermal field have not been made sufficiently clear and lack systematic research. Therefore, SiC single crystal growth, with different directions and rates in the direction of movement of the heating module, was modeled using a simulation method, and the law of variation of the physical field, including heat flux, temperature, powder porosity and growth rate parameters under different schemes, was analyzed. The study indicates that the decay of raw materials is the primary reason why growth conditions cannot be maintained. The results verified that different coils’ modes of movement have different effects on the improvement or adjustment of SiC crystals’ growth conditions. Under the same temperature control conditions, the coils’ movement rates of 200 μm/h, 0, −200 μm/h and −400 μm/h correspond to the average growth rates of 140, 152, 165 and 172 μm/h, respectively. The results show that downward displacement of the coils is beneficial in compensating for the deterioration of growth conditions, but it is easier to form convex surfaces and is not conducive to expanding diameter growth. This also verifies that the desired crystal growth state can be obtained by adjusting the position of the thermal field.
Tribological Properties of WS2 Thin Films Containing Graphite-like Carbon and Ni Interlayers
Authors: Romanov Roman I. , Fominski Dmitry V. , Demin Maxim V. , Gritskevich Mariya D. , Doroshina Natalia V. , Volkov Valentyn S. , Fominski Vyacheslav Yu.
Published: December 2022

The development and production of thin-film coatings having very low friction is an urgent problem of materials science. One of the most promising solutions is the fabrication of special nanocomposites containing transition-metal dichalcogenides and various carbon-based nanophases. This study aims to explore the influence of graphite-like carbon (g-C) and Ni interface layers on the tribological properties of thin WS2 films. Nanocrystalline WS2 films were created by reactive pulsed laser deposition (PLD) in H2S at 500 °C. Between the two WS2 nanolayers, g-C and Ni nanofilms were fabricated by PLD at 700 and 22 °C, respectively. Tribotesting was carried out in a nitrogen-enriched atmosphere by the reciprocal sliding of a steel counterbody under a relatively low load of 1 N. For single-layer WS2 films, the friction coefficient was ~0.04. The application of g-C films did not noticeably improve the tribological properties of WS2-based films. However, the application of thin films of g-C and Ni reduced the friction coefficient to 0.013, thus, approaching superlubricity. The island morphology of the Ni nanofilm ensured WS2 retention and altered the contact area between the counterbody and the film surface. The catalytic properties of nickel facilitated the introduction of S and H atoms into g-C. The sliding of WS2 nanoplates against an amorphous g-C(S, H) nanolayer caused a lower coefficient of friction than the relative sliding of WS2 nanoplates. The detected behavior of the prepared thin films suggests a new strategy of designing antifriction coatings for practical applications and highlights the ample opportunities of laser techniques in the formation of promising thin-film coatings.
Strengthened Spin Hall Effect of Circularly Polarized Light Enabled by a Single-Layered Dielectric Metasurface
Authors: Kim Minkyung , Lee Dasol
Published: December 2022

The spin Hall effect of light, referring to the spin-dependent and transverse splitting of light at an optical interface, is an interface-dependent phenomenon. In contrast to this commonly accepted statement, it has been recently reported that the spin Hall effect under circularly polarized light is interface-independent. Despite this interface-independence, however, the reflection of the spin Hall shifted beam is mostly suppressed under near-normal incidence, where the spin Hall shift is large because of the handedness reversal that occurs during the reflection. Here we present a single-layered dielectric metasurface to realize the interface-independent and strengthened spin Hall effect of light. Numerical simulation results confirmed that the anisotropic geometry of the metasurface induced phase-reversed reflection for one linear polarization and phase-preserved reflection for the other, thereby strongly strengthening the reflection of the spin-Hall-shifted beam. Our work will pave a route toward the precise displacement of the beam at the nanoscale without perturbing its polarization state.
Optimization Study on the Comfort of Human-Seat Coupling System in the Cab of Construction Machinery
Authors: Cheng Lei , Wen Hansheng , Ni Xiangyu , Zhuang Chao , Zhang Wenjian , Huang Haibo
Published: December 2022

The seat of a construction machinery cab is used as the research object. For the current human-seat coupling system comfort research methods and optimization index deficiencies, the seat body pressure comfort and vibration comfort at the same time optimized. Based on the more specialized Toyota 50 percentile dummy model, a human-seat finite element simulation model is established, and the body pressure distribution and vibration response are simulated and calculated. The transverse and longitudinal pressure distributions of the backrest and seat cushion and the pressure map are used to verify the simulation model’s body pressure comfort evaluation indexes. At the same time, the vibration response test is used to verify the vibration comfort evaluation indexes of the simulation model. The test results show that the accuracy of each evaluation index of the established coupling model is greater than 85%, which can provide model support for the subsequent optimization work. In order to improve the comfort of the seat of construction machinery during operation, the hardness of the upper sponge and lower layer sponge is reduced and increased by 10% and 15%, respectively, on the original seat. The body pressure comfort evaluation indexes of the ischium peak pressure, ischium mean pressure, thigh peak pressure and thigh mean pressure are used to evaluate the improved seat. The proposed optimization scheme is to reduce the hardness of the upper sponge and lower layer sponge of the seat cushion by 10% to improve the seat body pressure comfort. Finally, the evaluation indexes of body pressure comfort and vibration comfort are verified by four subjects in an improved seat, and the cushion pressure of different subjects is reduced while the vibration isolation rate is increased, which shows the rationality of the proposed optimization scheme. In addition, the evaluation results of the improved seat are different for subjects of different body sizes, with the most significant improvement for the subject of greater height and weight. The modeling and comfort evaluation methods adopted in the paper can provide a reference for the design and development of the seat.
Dimensional Error Prediction of Grinding Process Based on Bagging–GA–ELM with Robust Analysis
Authors: Yang Lei , Jiang Yibo , Liu Hua , Yang Xianna
Published: December 2022

Grinding, which determines the final dimension of parts, is an important process in manufacturing companies. In praxis, in order to avoid quality problems on the customer’s side, an online dimension check is normally used after the grinding process to ensure the product dimensions; however, it is always hysteretic and needs extra space and machine investment. To deal with the issue, dimensional error prediction of the grinding process is highly needed, and does not require extra space or machinery, as well as having better real-time performance. In this paper, a dimensional error prediction algorithm using principal component analysis (PCA), extreme learning machine (ELM), genetic algorithm (GA), and ensemble strategy (bagging algorithm) is designed. Specifically, PCA is used as a pre-treatment method to extract the main relevant components, then a bagging–GA–ELM model is constructed to predict the final product dimensional error after the grinding process, in which extreme learning machine (ELM) is utilized as a basic framework because of its fast calculation speed. GA, with its excellent global optimization capability, is implemented to search optimal input weights and thresholds of ELM, enabling ELM to obtain a better prediction performance. In addition, considering the complex environment of the industrial field, the bagging algorithm is employed to enhance the anti-noise ability of the proposed algorithm. Finally, the proposed algorithm is verified by a case from a bearing company.
Research on Intelligent Control System of Hydraulic Support Based on Position and Posture Detection
Authors: Zhang Yi , Zhang Hongyang , Gao Kuidong , Zeng Qingliang , Meng Fansheng , Cheng Jingyi
Published: December 2022

In the study of coal mining, the position and posture, the working status, and the straightness of the hydraulic support are critical to the safety of the coal mine. To detect and control the position of a hydraulic support, a model for solving the self-position and posture and a model for solving the relative position and pose of a hydraulic support based on the principle of three points determining a plane in space were established. Then, with the help of particle swarm optimization algorithm and Bang-Bang control algorithm, the hydraulic support position and the posture detection and control system are constructed. Finally, according to the requirements of sensor data collection and online monitoring of the position and posture of hydraulic support, a hydraulic support posture detection and control system is developed, and the simulation experiments of hydraulic support cylinder movement sample collecting, hydraulic support following motion and hydraulic support independent following machine are carried out on the self-developed three-machine intelligent control simulation experiment platform of the working face. However, the test under this simulation platform did not add the load of the top beam. The results show that the self-pose solution model and the relative-pose solution model of the hydraulic support can be used to quickly monitor the position and posture of the hydraulic support group. In the hydraulic support cylinder following motion movement, the largest following error of each cylinder is the balance cylinder, and its maximum error is 2.6 mm. In the hydraulic support independent following machine simulation, the maximum motion error of the support base is 2.2 mm. The position and posture detection and control system developed for hydraulic support can realize accurate detecting and control the position and posture of hydraulic support, as well as meet the requirements for industrial applications.
A Novel Permeability Prediction Model for Deep Coal via NMR and Fractal Theory
Authors: Song Lei , Gu Yongsheng , Zhang Lei , Wang Xiangyu
Published: December 2022

A quantitative description of the permeability of deep coal is of great significance for improving coalbed methane recovery and preventing gas disasters. The Schlumberger–Doll research (SDR) model is often used to predict rock permeability, but it has inherent defects in characterizing the pore structure of deep coal. In this study, a permeability model with fractal characteristics (FCP model) is established for deep coal based on nuclear magnetic resonance (NMR). The constants in the SDR model are theoretically explained by the relevant parameters in the FCP model. Centrifugation and NMR experiments were performed to determine the optimal centrifugal force and dual T2 cutoff values. The results show that the coal samples are mainly composed of micrometer and nanometer pores. The adsorption pores account for the largest proportion, followed by the percolation pores and migration pores. In addition, the prediction accuracy of the FCP model is significantly higher than that of the other three models, which provides a fast and effective method for the evaluation of deep coal permeability.
Error Probability of a Coherent M-ary PSK FSO System Influenced by Phase Noise
Authors: Petković Milica , Đorđević Goran T. , Makal Jarosław , Marjanović Zvezdan , Milovanović Gradimir V.
Published: December 2022

In this paper, we aim to develop an analytical framework for design and analysis of new generation mobile networks fronthaul/backhaul links based on the application of free-space optical (FSO) technology. Taking the receiver hardware imperfections into account, we present an efficient analytical approach in analyzing average symbol error probability (SEP) of the coherent FSO system employing M-ary phase-shift keying (PSK). Optical signal transmission is influenced by pointing errors and atmospheric turbulence. The signal intensity fluctuations caused by atmospheric turbulence are modeled by general Málaga (M) distribution, which takes into account the effect of multiple scattered components. We estimate the range of the signal-to-noise ratio at which the SEP floor appears, as well as the value of this non-removable error floor. The results illustrate that the effect of imperfect phase error compensation on the SEP is more critical under weaker turbulence conditions and for higher order modulation formats. Based on the analytical tools presented here, it is possible to estimate tolerable value of standard deviation of phase noise for the given value of SEP. This value of standard deviation is an important parameter in designing the phase-locked loop filter in the receiver.
Optimal Elliptic-Curve Subspaces for Applications in Double-Authenticated Requests in Mobile Distributed Data Mining
Authors: Hunyadi Daniel Ioan , Ticleanu Oana-Adriana , Constantinescu Nicolae
Published: December 2022

Mathematical models based on elliptic curves have been intensively studied since their applicability in data security systems was discovered. In this article, the authors describe the optimal way to select particular subspaces over which elliptic curves are defined, showing the applicability of these subspaces in secure data transfer. Access to large databases and analyses of the requests made to these databases are required daily by a variety of users, including legal entities. An attack on these communication systems causes violations in privacy and damage to/theft of data that can be worth EUR tens of billions annually. For requests made between computers, encryption methods can be used as these systems have adequate computing power and energy. For requests made from fixed and mobile systems, if the data are distributed heterogeneously, the computing power required to authenticate both the users and the answering entities determines the efficiency of the proposed solution. To address this limitation, our study proposes a double-authentication method based on particular elliptic-curve systems.
Robust Data Augmentation for Neural Machine Translation through EVALNET
Authors: Park Yo-Han , Choi Yong-Seok , Yun Seung , Kim Sang-Hun , Lee Kong-Joo
Published: December 2022

Since building Neural Machine Translation (NMT) systems requires a large parallel corpus, various data augmentation techniques have been adopted, especially for low-resource languages. In order to achieve the best performance through data augmentation, the NMT systems should be able to evaluate the quality of augmented data. Several studies have addressed data weighting techniques to assess data quality. The basic idea of data weighting adopted in previous studies is the loss value that a system calculates when learning from training data. The weight derived from the loss value of the data, through simple heuristic rules or neural models, can adjust the loss used in the next step of the learning process. In this study, we propose EvalNet, a data evaluation network, to assess parallel data of NMT. EvalNet exploits a loss value, a cross-attention map, and a semantic similarity between parallel data as its features. The cross-attention map is an encoded representation of cross-attention layers of Transformer, which is a base architecture of an NMT system. The semantic similarity is a cosine distance between two semantic embeddings of a source sentence and a target sentence. Owing to the parallelism of data, the combination of the cross-attention map and the semantic similarity proved to be effective features for data quality evaluation, besides the loss value. EvalNet is the first NMT data evaluator network that introduces the cross-attention map and the semantic similarity as its features. Through various experiments, we conclude that EvalNet is simple yet beneficial for robust training of an NMT system and outperforms the previous studies as a data evaluator.
Initial Problem for Two-Dimensional Hyperbolic Equation with a Nonlocal Term
Authors: Vasilyev Vladimir , Zaitseva Natalya
Published: December 2022

In this paper, we study the Cauchy problem in a strip for a two-dimensional hyperbolic equation containing the sum of a differential operator and a shift operator acting on a spatial variable that varies over the real axis. An operating scheme is used to construct the solutions of the equation. The solution of the problem is obtained in the form of a convolution of the function found using the operating scheme and the function from the initial conditions of the problem. It is proved that classical solutions of the considered initial problem exist if the real part of the symbol of the differential-difference operator in the equation is positive.
Versatile Stochastic Two-Sided Platform Models
Authors: Kim Song-Kyoo
Published: December 2022

This paper deals with the alternative mathematical modeling of the two-side platform. Two-sided platforms are specific multi-sided platforms that bring together two distinct groups of a model. The stochastic modeling by adapting various innovative mathematical methods including the first exceed theory and the stochastic pseudo-game theory has been applied for describing a two-sided platform more properly. A stochastic pseudo-game model is newly introduced to solve the two-sided platform more effectively. Analytically tractable results for operation thresholds for maximizing profits are provided and it also delivers the optimal balance of a two-sided platform. The paper includes how these innovative models are applied into various two-sided market situations. Additionally, users could conduct these multi-sided models to real business developments and the case practices of these unique models shall help the readers who want to find recommendations of their business situations easily even without having any mathematical background.
Germeier’s Scalarization for Approximating Solution of Multicriteria Matrix Games
Authors: Novikova Natalia , Pospelova Irina
Published: December 2022

In this paper, we study the properties of Germeier’s scalarization applied for solving multicriteria games. The equilibria and the equilibrium values of such games, as a rule, make sets, and the problems of parametrizing and approximating these sets arise. Shapley proved that Nash equilibrium of multicriteria matrix game can be found by solving a two-parametric family of scalar games obtained with the help of linear scalarization of the criteria vector. We show that Germeier’s scalarization parametrizes the equilibria of the multicriteria game by using one-parametric family of scalar games. Germeier’s scalarization has certain advantages over the linear one, and we suggest it for approximating the multicriteria game equilibria with a finite set. For two-criteria games with 2×2 matrices, we show by examples that there is no continuity of the values of scalar games in the scalarizing parameters. We prove one-sided (from the left or from the right) continuity for the game values. As a result, we come to convergence in Hausdorff metric for the set of equilibrium values obtained for ϵ-net on the simplex of scalarizing parameters to the value of the multicriteria game as ϵ→0. The constructed finite approximation may be helpful in practical applications, where players try to find a compromise in an iterative negotiating procedure under multiple criteria.
A Closed-Form Parametrization and an Alternative Computational Algorithm for Approximating Slices of Minkowski Sums of Ellipsoids in R3
Authors: Fahim Golestaneh Amirreza
Published: December 2022

The current work aims to develop an approximation of the slice of a Minkowski sum of finite number of ellipsoids, sliced up by an arbitrarily oriented plane in Euclidean space R3 that, to the best of the author’s knowledge, has not been addressed yet. This approximation of the actual slice is in a closed form of an explicit parametric equation in the case that the slice is not passing through the zones of the Minkowski surface with high curvatures, namely the “corners”. An alternative computational algorithm is introduced for the cases that the plane slices the corners, in which a family of ellipsoidal inner and outer bounds of the Minkowski sum is used to construct a “narrow strip” for the actual slice of Minkowski sum. This strip can narrow persistently for a few more number of constructing bounds to precisely coincide on the actual slice of Minkowski sum. This algorithm is also applicable to the cases with high aspect ratio of ellipsoids. In line with the main goal, some ellipsoidal inner and outer bounds and approximations are discussed, including the so-called “Kurzhanski’s” bounds, which can be used to formulate the approximation of the slice of Minkowski sum.
On the Regularity of Weak Solutions to Time-Periodic Navier–Stokes Equations in Exterior Domains
Authors: Eiter Thomas
Published: December 2022

Consider the time-periodic viscous incompressible fluid flow past a body with non-zero velocity at infinity. This article gives sufficient conditions such that weak solutions to this problem are smooth. Since time-periodic solutions do not have finite kinetic energy in general, the well-known regularity results for weak solutions to the corresponding initial-value problem cannot be transferred directly. The established regularity criterion demands a certain integrability of the purely periodic part of the velocity field or its gradient, but it does not concern the time mean of these quantities.
A Novel Control Hardware Architecture for Implementation of Fractional-Order Identification and Control Algorithms Applied to a Temperature Prototype
Authors: Gude Juan J. , García Bringas Pablo
Published: December 2022

In this paper, the conceptualization of a control hardware architecture aimed to the implementation of integer- and fractional-order identification and control algorithms is presented. The proposed hardware architecture combines the capability of implementing PC-based control applications with embedded applications on microprocessor- and FPGA-based real-time targets. In this work, the potential advantages of this hardware architecture over other available alternatives are discussed from different perspectives. The experimental prototype that has been designed and built to evaluate the control hardware architecture proposed in this work is also described in detail. The thermal-based process taking place in the prototype is characterized for being reconfigurable and exhibiting fractional behaviour, which results in a suitable equipment for the purpose of fractional-order identification and control. In order to demonstrate the applicability and effectiveness of the proposed control hardware architecture, integer- and fractional-order identification and control algorithms implemented in various control technologies have been applied to the temperature-based experimental prototype described before. Detailed discussion about results and identification and control issues are provided. The main contribution of this work is to provide an efficient and practical hardware architecture for implementing fractional-order identification and control algorithms in different control technologies, helping to bridge the gap between real-time hardware solutions and software-based simulations of fractional-order systems and controllers. Finally, some conclusions and concluding remarks are offered in the industrial context.
On Some Error Bounds for Milne’s Formula in Fractional Calculus
Authors: Ali Muhammad Aamir , Zhang Zhiyue , Fečkan Michal
Published: December 2022

In this paper, we found the error bounds for one of the open Newton–Cotes formulas, namely Milne’s formula for differentiable convex functions in the framework of fractional and classical calculus. We also give some mathematical examples to show that the newly established bounds are valid for Milne’s formula.
A Model for the Generalised Dispersion of Synovial Fluids on Nutritional Transport with Joint Impacts of Electric and Magnetic Field
Authors: Kumar B. Rushi , Vijayakumar R. , Rani A. Jancy
Published: December 2022

This work analyses the effect of electromagnetic fields on cartilaginous cells in human joints and the nutrients that flow from the synovial fluid to the cartilage. The perturbation approach and the generalised dispersion model is used to solve the governing equation of momentum and mass transfer. The dispersion coefficient increases with dimensionless time. It aids in grasping the level of nutritional transport to the synovial joint. Low-molecular-weight solutes have a lower concentration distribution at the same depth in articular cartilage than high-molecular-weight solutes. Thus, diffusion dominates nutrition transport for low-molecular-weight solutes, whereas a mechanical pumping action dominates nutrition transport for high-molecular-weight solutes. The report says that the cells in the centre of the cartilage surface receive more nutrients during imbibition and exudation than the cells on the periphery, and the earliest indications of cartilage degradation emerge in the uninflected regions. As a result, cartilage nutrition is considered necessary to joint mobility. It also predicts that, as the viscoelastic parameter increases, the concentration in the articular cartilage diminishes, resulting in the cartilage cells receiving less nutrition, which might lead to harmful effects. The dispersion coefficient and mean concentration for distinct factors, such as the Hartmann number, porous parameter, and viscoelastic parameters of gel formation, have been computed and illustrated through graphics.
Fatty Acids of Echinoderms: Diversity, Current Applications and Future Opportunities
Authors: Zhukova Natalia V.
Published: December 2022

The phylum Echinodermata comprising the classes Asteroidea, Ophiuroidea, Echinoidea, Holothuroidea, and Crinodeia, is one of the important invertebrate groups. Members of this phylum live exclusively in marine habitats and are distributed in almost all depths and latitudes. Some of them, such as sea urchins and sea cucumbers, are commercially valuable and constitute a major fishery resource. Echinoderms are increasingly recognized as a unique source of various metabolites with a wide range of biological activities. The importance of dietary polyunsaturated fatty acids, such as eicosapentaenoic acid, in human health has drawn attention to echinoderms as a promising source of essential fatty acids (FAs). Extensive information on the FAs of the phylum has been accumulated to date. The biosynthetic capabilities and feeding habits of echinoderms explain the findings of the unusual FAs in them. Certain common and unusual FAs may serve as chemotaxonomic markers of the classes. The main goal of the review was to gather the relevant information on the distribution of FAs among the echinoderm classes, describe the structures, distribution, biosynthetic pathways, and bioactivity, with an emphasis on the FAs specific for echinoderms. A large part of the review is devoted to the FAs derived from echinoderms that exhibit various biological activities promising for potential therapeutic applications.
Seaweed as a Natural Source against Phytopathogenic Bacteria
Authors: Vicente Tânia F. L. , Félix Carina , Félix Rafael , Valentão Patrícia , Lemos Marco F. L.
Published: December 2022

Plant bacterial pathogens can be devastating and compromise entire crops of fruit and vegetables worldwide. The consequences of bacterial plant infections represent not only relevant economical losses, but also the reduction of food availability. Synthetic bactericides have been the most used tool to control bacterial diseases, representing an expensive investment for the producers, since cyclic applications are usually necessary, and are a potential threat to the environment. The development of greener methodologies is of paramount importance, and some options are already available in the market, usually related to genetic manipulation or plant community modulation, as in the case of biocontrol. Seaweeds are one of the richest sources of bioactive compounds, already being used in different industries such as cosmetics, food, medicine, pharmaceutical investigation, and agriculture, among others. They also arise as an eco-friendly alternative to synthetic bactericides. Several studies have already demonstrated their inhibitory activity over relevant bacterial phytopathogens, some of these compounds are known for their eliciting ability to trigger priming defense mechanisms. The present work aims to gather the available information regarding seaweed extracts/compounds with antibacterial activity and eliciting potential to control bacterial phytopathogens, highlighting the extracts from brown algae with protective properties against microbial attack.
Long-Term Outcome of Patients with Stage II and III Muscle-Invasive Urothelial Bladder Cancer after Multimodality Approach. Which Is the Best Option?
Authors: Trifanescu Oana Gabriela , Gales Laurentia Nicoleta , Paun Mihai Andrei , Motas Natalia , Marinescu Serban Andrei , Virtosu Ion , Trifanescu Raluca Alexandra , Gherghe Mirela , Bilteanu Liviu , Diaconu Camelia Cristina , Anghel Rodica Maricela
Published: December 2022

Background and Objectives: There is no consensus regarding the optimal therapy sequence in stage II and III bladder cancer. The study aimed to evaluate the long-term oncologic outcomes in patients with bladder cancer after a multimodality approach. Materials and methods: Medical files of 231 consecutive patients identified with stage II (46.8%), IIIA (30.3%), and IIIB (22.9%) transitional cell carcinoma of the bladder (BC) treated with a multimodality approach were retrospectively reviewed. The treatment consisted of transurethral resections or cystectomy, radiotherapy alone or concurrent chemoradiotherapy as definitive treatment, or neoadjuvant chemotherapy using platinum salt regimens. Results: Median age at diagnosis was 65 ± 10.98 years. Radical or partial cystectomy was performed in 88 patients (37.1%), and trans-urethral resection of bladder tumor (TURBT) alone was performed in 143 (61.9%) patients. Overall, 40 patients (17.3%) received neoadjuvant chemotherapy and 82 (35.5%) received definitive chemoradiotherapy. After a median follow-up of 30.6 months (range 3–146 months), the median disease-free survival (DFS) for an entire lot of patients was 32 months, and the percentage of patients without recurrence at 12, 24, and 36 months was 86%, 58%, and 45%, respectively. Patients receiving neoadjuvant chemotherapy had a better oncologic outcome compared to patients without neoadjuvant chemotherapy (median DFS not reached vs. 31 months, p = 0.038, HR = 0.55, 95% CI 0.310–0.951). There was a trend for better 3-year DFS with radical cystectomy vs. TURBT (60 months vs. 31 months, p = 0.064). Definitive chemoradiotherapy 3-year DFS was 58% compared to 44% in patients who received radiotherapy or chemotherapy alone. Conclusions: In patients with stages II and III, both neoadjuvant chemotherapy and concurrent radio-chemotherapy are valid options for treatment and must be part of a multidisciplinary approach.
Comment on Hogas et al. Salt, Not Always a Cardiovascular Enemy? A Mini-Review and Modern Perspective. Medicina 2022, 58, 1175
Authors: Campbell Norm R. C. , Cappuccio Francesco P. , McLean Rachael M. , He Feng J. , MacGregor Graham A.
Published: December 2022

Hogas et al. recently published their perspective on dietary salt in a mini review [...]
A Chinese Classical Prescription Chaihu Shugan Powder in Treatment of Post-Stroke Depression: An Overview
Authors: Gao Zu , Wang Yuan , Yu Huayun
Published: December 2022

Post-stroke depression (PSD) is the most common mental health problem after a stroke with an incidence of up to 33%. PSD has a negative impact on the rehabilitation and recovery of motor and cognitive dysfunction after a stroke and significantly increases the chance of the recurrence of neurovascular events. At present, medication is the preferred method of coping with PSD. Modern medicine is still unclear regarding the pathogenesis of PSD, with clinical drug treatment mostly using antidepressants, such as selective serotonin reuptake inhibitor (SSRIs) and serotonin–norepinephrine reuptake inhibitors (SNRIs). However, a high proportion of patients fail to show an adequate antidepressant response and have adverse reactions after taking antidepressants. In recent years, as the advantages of traditional Chinese medicine (TCM) in clinical treatment continue to emerge, Chinese herbal and TCM formulae have begun to enter the awareness of Chinese scholars and even scholars around the world. As a classic formula with a history of more than 400 years, Chaihu Shugan powder (CHSG) has great advantages in the clinical treatment of PSD. Based on existing clinical and experimental studies, this article comprehensively analyzes clinical cases, mechanisms of action, and drug and chemical effects of CHSG in the treatment of PSD in order to provide more clinical experience and experimental theoretical support for CHSG in the treatment of PSD.
Different Causes of Functional Tricuspid Valve Regurgitation Are Linked to Differences in Tricuspid Valve and Right-Sided Heart Geometry and Function: 3D Echocardiography Study
Authors: Krivickienė Aušra , Verikas Dovydas , Krečkauskienė Rita , Padervinskienė Lina , Hoppenot Deimantė , Miliauskas Skaidrius , Vaškelytė Justina Jolanta , Ereminienė Eglė
Published: December 2022

Background and Objectives: The aim of this study was to clarify the tricuspid valve (TV) and right ventricular (RV) geometry and function characteristics using 3D echocardiography-based analysis and to identify echocardiographic predictors for severe tricuspid regurgitation (TR) in different etiologies of functional TR (fTR). Methods and Results: The prospective study included 128 patients (median age 64 years, 57% females): 109 patients with moderate or severe fTR (69-caused by dominant left-sided valvular pathology (LSVP), 40 due to precapillary pulmonary hypertension (PH)), and 19 healthy controls. The 2D and 3D-transthoracic echocardiography analysis included TV, right atrium, RV geometry, and functional parameters. All the RV geometry parameters as well as 3D TV parameters were increased in both fTR groups when compared to controls. Higher RV diameters, length, areas, volumes, and more impaired RV function were in PH group compared to LSVP group. PH was associated with larger leaflet tenting height, volume, and more increased indices of septal-lateral and major axis tricuspid annulus (TA) diameters. LVSP etiology was associated with higher anterior-posterior TA diameter and sphericity index. Univariate and multivariate logistic regression and ROC analyses revealed that different fTR etiologies were associated with various 2D and 3D echocardiographic parameters to predict severe TR: major axis TA diameter and TA perimeter, the leaflet tenting volume had the highest predictive value in PH group, septal-lateral systolic TA diameter-in LSVP group. The 3D TA analysis provided more reliable prediction for severe fTR. Conclusions: TV and RV geometry vary in different etiologies of functional TR. Precapillary PH is related to more severe RV remodeling and dysfunction and changes of TV geometry, when compared to LSVP group. The 3D echocardiography helps to determine echocardiographic predictors of severe TR in different fTR etiologies.
Prevalence and Characteristics of Fibromyalgia in Patients with Foot and Ankle Pain: The Experience of an Academic Podiatry Clinic
Authors: Ciaffi Jacopo , Brognara Lorenzo , Gangemi Giacomo , Vanni Elena , Assirelli Elisa , Neri Simona , Casadei Giulia , Mazzotti Antonio , Di Martino Alberto , Faldini Cesare , Zaffagnini Stefano , Ursini Francesco
Published: December 2022

Background and Objectives: Research about the prevalence of fibromyalgia in podiatric patients is limited, with data suggesting potentially higher estimates and greater foot impairment in patients with fibromyalgia compared to healthy individuals. The aim of our study is to assess the prevalence of fibromyalgia in the podiatric healthcare setting and to research the characteristics of fibromyalgia patients with foot or ankle disorders. Materials and Methods: Consecutive patients visiting the academic podiatry clinic at the University of Bologna IRCCS Rizzoli Orthopaedic Institute between 11 January and 31 March 2021 were enrolled. Results: Of the 151 patients included, 21 met the fibromyalgia survey diagnostic criteria, accounting for a prevalence of 13.9% (95% CI 8.8–20.5). As part of the podiatric assessment, the Foot Function Index (FFI) was used to calculate the impact of foot and ankle problems. Moreover, patients with fibromyalgia were asked to complete the fibromyalgia impact questionnaire (FIQ). Fibromyalgia patients had significantly worse total FFI scores (63.4 ± 23.0% vs. 53.2 ± 20.3%, p = 0.038) and there was a significant linear correlation between the FFI and the FIQ (r = 0.72, p < 0.001). Conclusions: The prevalence of fibromyalgia in the academic podiatry clinic being 13.9% confirms that, in the healthcare setting, the disease can be more frequent than in the general population. Furthermore, our findings suggest a strong correlation between foot impairment and the impact of fibromyalgia.