bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of Extracts of Two Selected Strains of Haematococcus pluvialis on Adipocyte Function
Authors: Pappalardo Ilaria , Santarsiero Anna , Radice Rosa Paola , Martelli Giuseppe , Grassi Giulia , de Oliveira Marcos Roberto , Infantino Vittoria , Todisco Simona
Published: August 2023

Recently, microalgae are arousing considerable interest as a source of countless molecules with potential impacts in the nutraceutical and pharmaceutical fields. Haematococcus pluvialis, also named Haematococcus lacustris, is the largest producer of astaxanthin, a carotenoid exhibiting powerful health effects, including anti-lipogenic and anti-diabetic activities. This study was carried out to investigate the properties of two selected strains of H. pluvialis (FBR1 and FBR2) on lipid metabolism, lipolysis and adipogenesis using an in vitro obesity model. FBR1 and FBR2 showed no antiproliferative effect at the lowest concentration in 3T3-L1 adipocytes. Treatment with FBR2 extract reduced lipid deposition, detected via Oil Red O staining and the immunocontent of the adipogenic proteins PPARγ, ACLY and AMPK was revealed using Western blot analysis. Extracts from both strains induced lipolysis in vitro and reduced the secretion of interleukin-6 and tumor necrosis factor-α. Moreover, the FBR1 and FBR2 extracts improved mitochondrial function, reducing the levels of mitochondrial superoxide anion radical and increasing mitochondrial mass compared to untreated adipocytes. These findings suggest that FBR2 extract, more so than FBR1, may represent a promising strategy in overweight and obesity prevention and treatment.
Exercise Effects on Left Ventricular Remodeling in Patients with Cardiometabolic Risk Factors
Authors: Bletsa Evanthia , Oikonomou Evangelos , Dimitriadis Kyriakos , Stampouloglou Panagiota K. , Fragoulis Christos , Lontou Stavroula P. , Korakas Emmanouil , Beneki Eirini , Kalogeras Konstantinos , Lambadiari Vaia , Tsioufis Konstantinos , Vavouranakis Manolis , Siasos Gerasimos
Published: August 2023

Left ventricular (LV) remodeling is a dynamic process, which is characterized by changes in ventricular size, shape, and wall thickness, thus altering myocardial geometry and function, and is considered as a negative prognostic factor in patients with heart failure (HF). Hypertension, type 2 diabetes (T2D), and obesity are strongly correlated with the development and the progression of LV remodeling, LV hypertrophy, and LV systolic and/or diastolic dysfunction. Indeed, the beneficial impact of exercise training on primary and secondary prevention of cardiovascular disease (CVD) has been well-established. Recent studies have highlighted that exercise training enhances functional capacity, muscle strength and endurance, cardiac function, and cardiac-related biomarkers among patients with established coronary artery disease (CAD) or HF, thus substantially improving their cardiovascular prognosis, survival rates, and need for rehospitalization. Therefore, in this review article, we discuss the evidence of LV remodeling in patients with cardiometabolic risk factors, such as hypertension, T2D, and obesity, and also highlight the current studies evaluating the effect of exercise training on LV remodeling in these patients.
Imaging in Gastroparesis: Exploring Innovative Diagnostic Approaches, Symptoms, and Treatment
Authors: Mandarino Francesco Vito , Testoni Sabrina Gloria Giulia , Barchi Alberto , Azzolini Francesco , Sinagra Emanuele , Pepe Gino , Chiti Arturo , Danese Silvio
Published: August 2023

Gastroparesis (GP) is a chronic disease characterized by upper gastrointestinal symptoms, primarily nausea and vomiting, and delayed gastric emptying (GE), in the absence of mechanical GI obstruction. The underlying pathophysiology of GP remains unclear, but factors contributing to the condition include vagal nerve dysfunction, impaired gastric fundic accommodation, antral hypomotility, gastric dysrhythmias, and pyloric dysfunction. Currently, gastric emptying scintigraphy (GES) is considered the gold standard for GP diagnosis. However, the overall delay in GE weakly correlates with GP symptoms and their severity. Recent research efforts have focused on developing treatments that address the presumed underlying pathophysiological mechanisms of GP, such as pyloric hypertonicity, with Gastric Peroral Endoscopic Myotomy (G-POEM) one of these procedures. New promising diagnostic tools for gastroparesis include wireless motility capsule (WMC), the 13 carbon-GE breath test, high-resolution electrogastrography, and the Endoluminal Functional Lumen Imaging Probe (EndoFLIP). Some of these tools assess alterations beyond GE, such as muscular electrical activity and pyloric tone. These modalities have the potential to characterize the pathophysiology of gastroparesis, identifying patients who may benefit from targeted therapies. The aim of this review is to provide an overview of the current knowledge on diagnostic pathways in GP, with a focus on the association between diagnosis, symptoms, and treatment.
Characterization of Base Oil and Additive Oxidation Products from Formulated Lubricant by Ultra-High Resolution Mass Spectrometry
Authors: Lacroix-Andrivet Oscar , Hubert-Roux Marie , Loutelier Bourhis Corinne , Moualdi Samira , Mendes Siqueira Anna Luiza , Afonso Carlos
Published: August 2023

Automotive formulated lubricants are high value products composed of 80% base oil and 20% various additives. During their life service, lubricants are exposed to several factors that will cause degradation over time, such as high temperature, shear, and oxidation. Base oil is a complex combination of hydrocarbons that are relatively sensitive to oxidation. During the initiation phase of oxidation, free radicals are formed, leading to the production of hydroperoxide ROOH and an alkyl radical R•. These compounds will react with the base oil molecules to form aldehydes, ketones, and carboxylic acids in the termination phase. Owing to the molecular complexity of these mixtures, Fourier transform mass spectrometry seems to be the most appropriate tool to cover their wide range of compounds due to its ultra-high resolving power and mass accuracy. In this study, a native formulated lubricant and its different oxidized states at 140 °C under air flow (3, 5, 7, 8, and 9 days of oxidation) were analyzed by FTICR MS. The combination of atmospheric pressure chemical ionization (APCI) was used to achieve a non-selective ionization of molecules, including base oils, while Electrospray ionization (ESI) was used to selectively ionize acidic molecules. Apparent Kendrick mass defect (aKMD) plots were used to separate homologous series of molecules on different horizontal lines on the basis of the CH2 repetition unit. Aging of lubricants was mainly characterized by a rapid consumption of certain additive families, such as molybdenum dithiocarbamates (MoDTCs) and zinc dithiophosphate (ZnDTPs), but also by the emergence of many oxidation products. Thus, the presence of aldehydes, ketones, and acids was characterized in the early stage of aging while larger products from polymerization were observed in a more advanced stage of aging. Interaction products between peroxy radicals and hindered phenols/alkyl diphenylamines (ADPAs) antioxidations were elucidated toward the high m/z. The formation of such products can be explained by trapping mechanisms of these additives at high temperature (>120 °C). Other types of interaction products were observed with the formation of antioxidant complexes. Additive degradation products were also characterized. For instance, polyisobutenyl succinimide dispersant oxidation products were clearly evidenced on the aKMD plots due to the gaps of 56 Da between each point. Overall, this study demonstrated the efficiency of the aKMD approach, and the use of ESI/APCI to characterize base oil and additive oxidation products.
Hot Deformation Behavior and Dynamic Softening Mechanism in 7B50 Aluminum Alloy
Authors: Li Ming , Li Yong , Liu Yu , Xiao Zhengbing , Huang Yuanchun
Published: August 2023

The hot deformation behavior and dynamic softening mechanism of 7B50 aluminum alloy were studied via isothermal compression experiments in the range of 320–460 °C/0.001–1.0 s−1. According to the flow curves obtained from the experiments, the flow behavior of this alloy was analyzed, and the Zener–Hollomon (Z) parameter equation was established. The hot processing maps of this alloy were developed based on the dynamic material model, and the optimal hot working region was determined to be 410–460 °C/0.01–0.001 s−1. The electron backscattered diffraction (EBSD) microstructure analysis of the deformed sample shows that the dynamic softening mechanism and microstructure evolution strongly depend on the Z parameter. Meanwhile, a correlation between the dynamic softening mechanism and the lnZ value was established. Dynamic recovery (DRV) was the only softening mechanism during isothermal compression with lnZ ≥ 20. Discontinuous dynamic recrystallization (DDRX) becomes the dominant dynamic recrystallization (DRX) mechanism under deformation conditions of 15 < lnZ < 20. Meanwhile, the size and percentage of DDRXed grains increased with decreasing lnZ values. The geometric dynamic recrystallization (GDRX) mechanism and continuous dynamic recrystallization (CDRX) mechanism coexist under deformation conditions with lnZ ≤ 15.
Heat and Mass Transfer in Porous Materials
Authors: Pavlenko Anatoliy
Published: August 2023

Currently, porous materials (PM) are actively used in many fields of science and technology, and the processes of heat and mass transfer in porous materials underlie a wide variety of industrial technologies [...]
Study on the Influences of Adding Rare Earth Ce on the Precipitation Behaviors of TiN Inclusions in 20CrMnTi
Authors: Wang Jian , Peng Jun , Liu Lixia , Zhang Fang , Peng Jihua , Tang Hao , Zheng Jie , An Shengli
Published: August 2023

The morphologies and sizes of TiN inclusions in gear steel 20CrMnTi have a significant impact on its service performance. This paper selects rare earth Ce to modify TiN inclusions in 20CrMnTi. The inclusions are analyzed by SEM (scanning electron microscope), EBSD (electron back-scattered diffraction), EDS (energy disperse spectroscopy), and OTS statistical software, and Thermo-Calc software is used to calculate the inclusion formations. The inclusions of MgAlO4-Ce and CeAlO3 can be formed when rare earth Ce is added into 20CrMnTi, which becomes TiN nucleation core after precipitation. Without the addition of rare earth Ce, square TiN inclusions ranging from 2 to 5 μm account for 60% of the total inclusions in 20CrMnTi. After adding rare earth Ce, the TiN inclusions in 20CrMnTiCe account for 36.7% of the total inclusions. Due to the new phase formations of MgAlO4-TiN and CeAlO3-TiN with sizes less than 2 μm, the titanium-containing inclusions are refined. Fatigue tests are conducted on the steels before and after the addition of Ce. The average fatigue lives of 20CrMnTi do not reach 107 times, and the deviations between the maximum and minimum fatigue lives are great. Large-sized TiN are the main inclusions that affect the fatigue performance of 20CrMnTi. The average fatigue lives of 20CrMnTiCe exceed 107 times, and the deviations of the fatigue lives are smaller than those of 20CrMnTi.
Two-Step Thermal Transformation of Multilayer Graphene Using Polymeric Carbon Source Assisted by Physical Vapor Deposited Copper
Authors: Huang Yong , Ni Jiamiao , Shi Xiaoyu , Wang Yu , Yao Songsong , Liu Yue , Fan Tongxiang
Published: August 2023

Direct in situ growth of graphene on dielectric substrates is a reliable method for overcoming the challenges of complex physical transfer operations, graphene performance degradation, and compatibility with graphene-based semiconductor devices. A transfer-free graphene synthesis based on a controllable and low-cost polymeric carbon source is a promising approach for achieving this process. In this paper, we report a two-step thermal transformation method for the copper-assisted synthesis of transfer-free multilayer graphene. Firstly, we obtained high-quality polymethyl methacrylate (PMMA) film on a 300 nm SiO2/Si substrate using a well-established spin-coating process. The complete thermal decomposition loss of PMMA film was effectively avoided by introducing a copper clad layer. After the first thermal transformation process, flat, clean, and high-quality amorphous carbon films were obtained. Next, the in situ obtained amorphous carbon layer underwent a second copper sputtering and thermal transformation process, which resulted in the formation of a final, large-sized, and highly uniform transfer-free multilayer graphene film on the surface of the dielectric substrate. Multi-scale characterization results show that the specimens underwent different microstructural evolution processes based on different mechanisms during the two thermal transformations. The two-step thermal transformation method is compatible with the current semiconductor process and introduces a low-cost and structurally controllable polymeric carbon source into the production of transfer-free graphene. The catalytic protection of the copper layer provides a new direction for accelerating the application of graphene in the field of direct integration of semiconductor devices.
Properties of Superelastic Nickel–Titanium Wires after Clinical Use
Authors: Alcaraz Inés , Moyano Javier , Pàmies Ariadna , Ruiz Guillem , Artés Montserrat , Gil Javier , Puigdollers Andreu
Published: August 2023

The aim of the present study was to describe and determine changes in the superelastic properties of NiTi archwires after clinical use and sterilization. Ten archwires from five different manufacturers (GAC, 3M, ODS, GC, FOR) were cut into two segments and evaluated using a three-point bending test in accordance with ISO 14841:2006. The center of each segment was deflected to 3.1 mm and then unloaded to 0 N to obtain a load–deflection curve. Deflection at the end of the plateau and forces at 3, 2, 1 and 0.5 mm on the unloading curve were recorded. Plateau slopes were calculated at 2, 1 and 0.5 mm of deflection. Data obtained were statistically analyzed to determine differences (p < 0.001). Results showed that the degree of superelasticity and exerted forces differed significantly among brand groups. After three months of clinical use, FOR released a greater force for a longer activation period. GC, EURO and FOR archwires seemed to lose their mechanical properties. GC wires released more force than other brand wires after clinical use. Regarding superelasticity after sterilization, GAC, 3M and FOR wires recovered their properties, while EURO archwires lost more.
The Effects of Different Femoral Component Materials on Bone and Implant Response in Total Knee Arthroplasty: A Finite Element Analysis
Authors: Galas Allegra , Banci Lorenzo , Innocenti Bernardo
Published: August 2023

Due to the high stiffness of the biomaterials used in total knee arthroplasty, stress shielding can lead to decreased periprosthetic bone mineral density and bone resorption. As different materials and 3D-printed highly porous surfaces are available for knee femoral components from the industry nowadays, this study aimed to compare the effects of two same-design cruciate-retaining femoral components, made with CoCr and titanium alloy, respectively, on periprosthetic bone stresses through a finite element model of the implanted knee in order to evaluate the induced stress shielding. Moreover, the effect of the cementless highly porous surface of the titanium implant was analyzed in comparison to the cemented interface of the CoCr implant. The von Mises stresses were analyzed in different periprosthetic regions of interest of the femur with different configurations and knee flexion angles. The titanium component induced higher bone stresses in comparison with the CoCr component, mostly in the medial compartment at higher knee flexion angles; therefore, the CoCr component led to more stress shielding. The model was revealed to be effective in describing the effects of different femoral component materials on bone stress, highlighting how a cementless, highly porous titanium femoral component might lead to less stress shielding in comparison to a cemented CoCr implant with significant clinical relevance and reduced bone resorption after total knee arthroplasty.
Analyzing the Role of Fe0 and Fe3+ in the Formation of Expanded Clay Aggregates
Authors: Moreno-Maroto José Manuel , González-Corrochano Beatriz , Martínez-Rodríguez Ana M. , Conde-Sánchez Antonio , Cobo-Ceacero Carlos Javier , Alonso-Azcárate Jacinto , Uceda-Rodríguez Manuel , López Ana B. , Martínez-García Carmen , Cotes-Palomino Teresa
Published: August 2023

The effect of the addition of Fe0 and Fe3+ on the formation of expanded clay aggregates was studied using iron-free kaolin as an aluminosilicates source. Likewise, the incorporation of cork powder as a source of organic carbon and Na2CO3 as a flux in the mixtures was investigated in order to assess its effect in combination with the iron phases. An experimental protocol, statistically supported by a mixture experiments/design of experiments approach, was applied to model and optimize the bloating index, density, absorption capacity, and mechanical strength. The process of expansion and pore generation and the associated decrease in density required the addition of iron, such that the optimum mixtures of these properties presented between 25 and 40 wt.% of Fe0 or Fe3+, as well as the incorporation of 3.5–5 wt.% of organic carbon. The addition of Fe3+ produced a greater volumetric expansion (max. 53%) than Fe0 (max. 8%), suggesting that the formation of the FeO leading to this phenomenon would require reducing and oxidizing conditions in the former and the latter, respectively. The experimental and model-estimated results are in good agreement, especially in the aggregates containing Fe0. This reinforces the application of statistical methods for future investigations.
Characterization of SiO2 Plasma Etching with Perfluorocarbon (C4F8 and C6F6) and Hydrofluorocarbon (CHF3 and C4H2F6) Precursors for the Greenhouse Gas Emissions Reduction
Authors: Choi Minsu , Lee Youngseok , You Yebin , Cho Chulhee , Jeong Wonnyoung , Seong Inho , Choi Byeongyeop , Kim Sijun , Seol Youbin , You Shinjae , Yeom Geun Young
Published: August 2023

This paper proposes the use of environmentally friendly alternatives, C6F6 and C4H2F6, as perfluorocarbon (PFC) and hydrofluorocarbon (HFC) precursors, respectively, for SiO2 plasma etching, instead of conventional precursors C4F8 and CHF3. The study employs scanning electron microscopy for etch profile analysis and quadrupole mass spectrometry for plasma diagnosis. Ion bombardment energy at the etching conditions is determined through self-bias voltage measurements, while densities of radical species are obtained using quadrupole mass spectroscopy. The obtained results compare the etch performance, including etch rate and selectivity, between C4F8 and C6F6, as well as between CHF3 and C4H2F6. Furthermore, greenhouse gas (GHG) emissions are evaluated using a million metric ton of carbon dioxide equivalent, indicating significantly lower emissions when replacing conventional precursors with the proposed alternatives. The results suggest that a significant GHG emissions reduction can be achieved from the investigated alternatives without a deterioration in SiO2 etching characteristics. This research contributes to the development of alternative precursors for reducing global warming impacts.
Time-Varying Formation Tracking for Second Order Multi-Agent Systems: An Experimental Approach for Wheeled Robots
Authors: Gonzalez-Yances Neftali J. , Morales-Diaz America B. , Becerra Héctor M.
Published: August 2023

In this paper, a time-varying formation tracking protocol for second-order multi-sgent systems (MASs) is presented. The time-varying formation considers translation, rotation, and scaling of the geometric pattern that defines the formation. The control law is simple yet effective, and it is composed of a trajectory tracking control and a consensus control that considers the position and velocity feedback of the connected agents in the MAS. The closed-loop system is asymptotically stable, and this was proved using the Gershgoring’s disk theorem. The performance of the protocol was extensively tested in experiments using a dynamic extension of the differential-drive robot model. The protocol was tested for different communication topologies and also dealt with switching topologies. The proposed protocol presented good performance regaring both time-varying formation and topology changes. Moreover, a comparison with an existing controller and with only trajectory tracking control has been provided, thus showing that the proposed protocol preserves the formation for all the tested topologies in a better way.
One New Property of a Class of Linear Time-Optimal Control Problems
Authors: Penev Borislav
Published: August 2023

The following paper deals with a new property of linear time-optimal control problems with real eigenvalues of the system. This property unveils the possibility of synthesizing the time-optimal control without describing the switching hyper-surfaces. Furthermore, the novel technique offers an alternative solution to the classic example of the time-optimal control of a double integrator system.
Concurrent Topology Optimization of Multi-Scale Composite Structures Subjected to Dynamic Loads in the Time Domain
Authors: Jiang Xudong , Zhang Wei , Teng Xiaoyan , Chen Xiangyang
Published: August 2023

This paper presents a concurrent topology optimization of multi-scale composite structures subjected to general time-dependent loads for minimizing dynamic compliance. A three-field density-based method is adopted to implement the concurrent topological design, with macroscopic effective properties of the microstructure evaluated through energy-based homogenization method (EBHM). Transient response is obtained from the two-scale finite element analysis with the HHT-α approach as an implicit time integration procedure. Design sensitivities are formulated employing the adjoint variable method (AVM) based on two main philosophies: “discretize-then-differentiate” and “differentiate-then-discretize” approaches, respectively. The method of moving asymptotes is adopted to update the design variables at two scales. Several benchmark examples are presented to demonstrate that the “discretize-then-differentiate” AVM attains consistent sensitivities in an inherent manner such that the resulting optimal topology is more efficient when compared with the “differentiate-then-discretize” AVM. Moreover, the potential of the proposed method for concurrent dynamic topology optimization problems under general time-dependent loads is also highlighted.
3D Simulation of Debris Flows with the Coupled Eulerian–Lagrangian Method and an Investigation of the Runout
Authors: Xu Haoding , He Xuzhen , Shan Feng , Niu Gang , Sheng Daichao
Published: August 2023

In landslide risk management, it is important to estimate the run-out distance of landslides (or debris flows) such that the consequences can be estimated. This research presents an innovative array of dimensionless equations that effectively estimate run-out distances, supported by both experimental data and numerical simulations. We employ the coupled Eulerian–Lagrangian (CEL) method to confront the challenges presented in large deformations during landslides. The soil is modelled using the Mohr–Coulomb model, and the failure of cohesionless soil slopes (e.g., sand slopes) is studied. The simulation results are used to study the characteristics of flows and run-out distances. We suggest a normalized run-out and introduce new scaling relationships for it under different conditions such as different plane angles and material properties. The granular flows under different scales can be compared directly with this new scaling law. The new relationships are validated by both experimental and numerical data. Our analysis reveals that the normalized run-out distance in debris flows is contingent on the initial geometry, plane angle, and material properties. An increase in debris volume and plane angle can contribute to an increase in the normalized run-out distance, while a rise in friction angles causes a decrease. In the case of landslides, the normalized run-out distance depends on material properties and the slope angle. An increase in slope angle leads to a corresponding increase in the normalized run-out distance.
Equivalent Conditions of Complete p-th Moment Convergence for Weighted Sum of ND Random Variables under Sublinear Expectation Space
Authors: Sun Peiyu , Wang Dehui , Tan Xili
Published: August 2023

We investigate the complete convergence for weighted sums of sequences of negative dependence (ND) random variables and p-th moment convergence for weighted sums of sequences of ND random variables under sublinear expectation space. Using moment inequality and truncation methods, we prove the equivalent conditions of complete convergence for weighted sums of sequences of ND random variables and p-th moment convergence for weighted sums of sequences of ND random variables under sublinear expectation space.
Surface Pencil Pair Interpolating Bertrand Pair as Common Asymptotic Curves in Euclidean 3-Space
Authors: Mofarreh Fatemah , Abdel-Baky Rashad A.
Published: August 2023

In this paper, we obtain the necessary and sufficient conditions of a surface pencil pair interpolating a Bertrand pair as common asymptotic curves in Euclidean 3-space E3. Afterwards, the conclusion to the ruled surface pencil pair is also obtained. Meanwhile, the epitomes are stated to emphasize that the proposed methods are effective in product manufacturing by adjusting the shapes of the surface pencil pair.
Optimization of Low-Cost Data Acquisition Equipment Applied to Bearing Condition Monitoring
Authors: Soto-Ocampo César Ricardo , Maroto Joaquín , Cano-Moreno Juan David , Mera José Manuel
Published: August 2023

The development of low-cost data acquisition equipment is relevant in the increasingly automated industry of today. This study presents the optimization of low-cost data acquisition equipment performance to achieve acquisition speeds of 200 kHz. This was possible by evaluating two essential aspects: considering the influence of the power supplied by the power source and changing the type of data used from “Double” to “uint”. This equipment was validated through the acquisition of known waves and vibration signals from a bearing test bench. The frequency component was satisfactorily identified in each case, for both the known waves and the damaged bearing components. This demonstrated the viability of developing low-cost data acquisition equipment that can be implemented to monitor bearing condition.
Prediction of Rockburst Propensity Based on Intuitionistic Fuzzy Set—Multisource Combined Weights—Improved Attribute Measurement Model
Authors: Chen Jianhong , Zhao Yakun , Liu Zhe , Yang Shan , Zhou Zhiyong
Published: August 2023

A rockburst is a geological disaster that occurs in resource development or engineering construction. In order to reduce the harm caused by rockburst, this paper proposes a prediction study of rockburst propensity based on the intuitionistic fuzzy set-multisource combined weights-improved attribute measurement model. From the perspective of rock mechanics, the uniaxial compressive strength σc, tensile stress σt, shear stress σθ, compression/tension ratio σc/σt, shear/compression ratio σθ/σc, and elastic deformation coefficient Wet were selected as the indicators for predicting the propensity of rockburst, and the corresponding attribute classification set was established. Constructing a model framework based on an intuitionistic fuzzy set–improved attribute measurement includes transforming the vagueness of rockburst indicators with an intuitionistic fuzzy set and controlling the uncertainty in the results of the attribute measurements, as well as improving the accuracy of the model using the Euclidean distance method to improve the attribute identification method. To further transform the vagueness of rockburst indicators, the multisource system for combined weights of rockburst propensity indicators was constructed using the minimum entropy combined weighting method, the game theory combined weighting method, and the multiplicative synthetic normalization combined weighting method integrated with intuitionistic fuzzy sets, and the single-valued data of the indicators were changed into intervalized data on the basis of subjective weights based on the analytic hierarchy process and objective weights, further based on the coefficient of variation method. Choosing 30 groups of typical rockburst cases, the indicator weights and propensity prediction results were calculated and analyzed through this paper’s model. Firstly, comparing the prediction results of this paper’s model with the results of the other three single-combination weighting models for attribute measurement, the accuracy of the prediction results of this paper’s model is 86.7%, which is higher than that of the other model results that were the least in addition to the number of uncertain cases, indicating that the uncertainty of attribute measurement has been effectively dealt with; secondly, the rationality of the multiple sources system for combined weights is verified, and the vagueness of the indicators is controlled.
Inclusion Properties of p-Valent Functions Associated with Borel Distribution Functions
Authors: Amini Ebrahim , Fardi Mojtaba , Zaky Mahmoud A. , Lopes António M. , Hendy Ahmed S.
Published: August 2023

In this paper, we define a differential operator on an open unit disk Δ by using the novel Borel distribution (BD) operator and means of convolution. This operator is adopted to introduce new subclasses of p-valent functions through the principle of differential subordination, and we focus on some interesting inclusion relations of these classes. Additionally, some inclusion relations are derived by using the Bernardi integral operator. Moreover, relevant convolution results are established for a class of analytic functions on Δ, and other results of analytic univalent functions are derived in detail. This study provides a new perspective for developing p-univalent functions with BD and offers valuable understanding for further research in complex analysis.
A New R-Function to Estimate the PDF of the Product of Two Uncorrelated Normal Variables
Authors: Seijas-Macias Antonio , Oliveira Amílcar , Oliveira Teresa A.
Published: August 2023

This paper analyses the implementation of a procedure using the software R to calculate the Probability Density Function (PDF) of the product of two uncorrelated Normally Distributed Random Variables. The problem of estimating the distribution of the product of two random variables has been solved for some particular cases, but there is no unique expression for all possible situations. In our study, we chose Rohatgi’s theorem as a basis for approximating the product of two uncorrelated Normally Distributed Random Variables. The numerical approximation of the product PDF was calculated using a function that we implemented in R. Several numerical examples show that the approximations obtained in R fit the theoretical values of the product distributions. The results obtained with our R function are very positive when we compare them with the Monte Carlo Simulation of the product of the two variables.
Pharmacological and Non-Pharmacological Treatments for Depression in Parkinson’s Disease: An Updated Review
Authors: Angelopoulou Efthalia , Stanitsa Evangelia , Karpodini Claire Chrysanthi , Bougea Anastasia , Kontaxopoulou Dionysia , Fragkiadaki Stella , Koros Christos , Georgakopoulou Vasiliki Epameinondas , Fotakopoulos George , Koutedakis Yiannis , Piperi Christina , Papageorgiou Sokratis G.
Published: August 2023

Depression represents one of the most common non-motor disorders in Parkinson’s disease (PD) and it has been related to worse life quality, higher levels of disability, and cognitive impairment, thereby majorly affecting not only the patients but also their caregivers. Available pharmacological therapeutic options for depression in PD mainly include selective serotonin reuptake inhibitors, serotonin and norepinephrine reuptake inhibitors, and tricyclic antidepressants; meanwhile, agents acting on dopaminergic pathways used for motor symptoms, such as levodopa, dopaminergic agonists, and monoamine oxidase B (MAO-B) inhibitors, may also provide beneficial antidepressant effects. Recently, there is a growing interest in non-pharmacological interventions, including cognitive behavioral therapy; physical exercise, including dance and mind–body exercises, such as yoga, tai chi, and qigong; acupuncture; therapeutic massage; music therapy; active therapy; repetitive transcranial magnetic stimulation (rTMS); and electroconvulsive therapy (ECT) for refractory cases. However, the optimal treatment approach for PD depression is uncertain, its management may be challenging, and definite guidelines are also lacking. It is still unclear which of these interventions is the most appropriate and for which PD stage under which circumstances. Herein, we aim to provide an updated comprehensive review of both pharmacological and non-pharmacological treatments for depression in PD, focusing on recent clinical trials, systematic reviews, and meta-analyses. Finally, we discuss the pharmacological agents that are currently under investigation at a clinical level, as well as future approaches based on the pathophysiological mechanisms underlying the onset of depression in PD.
An Update on Obstructive Sleep Apnea Syndrome—A Literature Review
Authors: Platon Alexandra Lorina , Stelea Carmen Gabriela , Boișteanu Otilia , Patrascanu Emilia , Zetu Irina Nicoleta , Roșu Sorana Nicoleta , Trifan Valentina , Palade Dragoș Octavian
Published: August 2023

Obstructive sleep apnea syndrome (OSAS) is the most common breathing-related sleep disorder. It is characterized by recurrent episodes of partial or complete airway obstruction during sleep, resulting in a reduction in or the total cessation of airflow, despite ongoing respiratory efforts, leading to oxygen desaturation and arousal. The purpose of this literature review is to evaluate the most common characteristics of this pathology, as well as to investigate the most effective treatment options, providing an update on the management of OSA patients.
Diurnal Variation in and Optimal Time to Measure Holter-Based Late Potentials to Predict Lethal Arrhythmia after Myocardial Infarction
Authors: Hashimoto Kenichi , Harada Naomi , Kimata Motohiro , Kawamura Yusuke , Fujita Naoya , Sekizawa Akinori , Ono Yosuke , Obuchi Yasuhiro , Takayama Tadateru , Kasamaki Yuji , Tanaka Yuji
Published: August 2023

Background and Objectives: Holter-based late potentials (LPs) are useful for predicting lethal arrhythmias in organic cardiac diseases. Although Holter-based LPs exhibit diurnal variation, no studies have evaluated the optimal timing of LP measurement over 24 h for predicting lethal arrhythmia that leads to sudden cardiac death. Thus, this study aimed to validate the most effective timing for Holter-based LP testing and to explore factors influencing the diurnal variability in LP parameters. Materials and Methods: We retrospectively analyzed 126 patients with post-myocardial infarction (MI) status and 60 control participants who underwent high-resolution Holter electrocardiography. Among the 126 post-MI patients, 23 developed sustained ventricular tachycardia (VT) (the MI-VT group), while 103 did not (the MI-non-VT group) during the observation period. Holter-based LPs were measured at 0:00, 4:00, 8:00, 12:00, 16:00, and 20:00, and heart rate variability analysis was simultaneously performed to investigate factors influencing the diurnal variability in LP parameters. Results: Holter-based LP parameters showed diurnal variation with significant deterioration at night and improvement during the day. Assessment at the time with the longest duration of low-amplitude signals < 40 μV in the filtered QRS complex terminus (LAS40) gave the highest receiver operating characteristics curve (area under the curve, 0.659) and the highest odds ratio (3.75; 95% confidence interval, 1.45–9.71; p = 0.006) for predicting VT. In the multiple regression analysis, heart rate and noise were significant factors affecting the LP parameters in the MI-VT and control groups. In the non-VT group, the LP parameters were significantly influenced by noise and parasympathetic heart rate variability parameters, such as logpNN50. Conclusions: For Holter-based LP measurements, the test accuracy was higher when the LP was measured at the time of the highest or worst value of LAS40. Changes in autonomic nervous system activity, including heart rate, were factors influencing diurnal variability. Increased parasympathetic activity or bradycardia may exacerbate Holter-based LP parameters.
Role of Circular RNAs in Atherosclerosis through Regulation of Inflammation, Cell Proliferation, Migration, and Apoptosis: Focus on Atherosclerotic Cerebrovascular Disease
Authors: Zhang Zheng , Li Lingfei , Shi Huanqing , Chen Biao , Li Xiaoqin , Zhang Yuyao , Liu Fei , Wei Wan , Zhou Yongji , Liu Keqin , Xia Wenqing , Gu Xin , Huang Jinyu , Tu Sheng , Yin Congguo , Shao Anwen , Jiang Lin
Published: August 2023

Atherosclerosis (AS) is a disease dangerous to human health and the main pathological cause of ischemic cardiovascular diseases. Although its pathogenesis is not fully understood, numerous basic and clinical studies have shown that AS is a chronic inflammatory disease existing in all stages of atherogenesis. It may be a common link or pathway in the pathogenesis of multiple atherogenic factors. Inflammation is associated with AS complications, such as plaque rupture and ischemic cerebral infarction. In addition to inflammation, apoptosis plays an important role in AS. Apoptosis is a type of programmed cell death, and different apoptotic cells have different or even opposite roles in the process of AS. Unlike linear RNA, circular RNA (circRNA) a covalently closed circular non-coding RNA, is stable and can sponge miRNA, which can affect the stages of AS by regulating downstream pathways. Ultimately, circRNAs play very important roles in AS by regulating inflammation, apoptosis, and some other mechanisms. The study of circular RNAs can provide new ideas for the prediction, prevention, and treatment of AS.
PCL/PEO Polymer Membrane Prevents Biofouling in Wearable Detection Sensors
Authors: Delgado-Rivera Roberto , García-Rodríguez William , López Luis , Cunci Lisandro , Resto Pedro J. , Domenech Maribella
Published: August 2023

Technological advances in biosensing offer extraordinary opportunities to transfer technologies from a laboratory setting to clinical point-of-care applications. Recent developments in the field have focused on electrochemical and optical biosensing platforms. Unfortunately, these platforms offer relatively poor sensitivity for most of the clinically relevant targets that can be measured on the skin. In addition, the non-specific adsorption of biomolecules (biofouling) has proven to be a limiting factor compromising the longevity and performance of these detection systems. Research from our laboratory seeks to capitalize on analyte selective properties of biomaterials to achieve enhanced analyte adsorption, enrichment, and detection. Our goal is to develop a functional membrane integrated into a microfluidic sampling interface and an electrochemical sensing unit. The membrane was manufactured from a blend of Polycaprolactone (PCL) and Polyethylene oxide (PEO) through a solvent casting evaporation method. A microfluidic flow cell was developed with a micropore array that allows liquid to exit from all pores simultaneously, thereby imitating human perspiration. The electrochemical sensing unit consisted of planar gold electrodes for the monitoring of nonspecific adsorption of proteins utilizing Cyclic Voltammetry (CV) and Electrochemical Impedance Spectroscopy (EIS). The solvent casting evaporation technique proved to be an effective method to produce membranes with the desired physical properties (surface properties and wettability profile) and a highly porous and interconnected structure. Permeability data from the membrane sandwiched in the flow cell showed excellent permeation and media transfer efficiency with uniform pore activation for both active and passive sweat rates. Biofouling experiments exhibited a decrease in the extent of biofouling of electrodes protected with the PCL/PEO membrane, corroborating the capacity of our material to mitigate the effects of biofouling.
Treatment of Multi-Walled Carbon Nanotubes with Dichromic Acid: Oxidation and Appearance of Intercalation
Authors: Golovakhin Valeriy , Kim Ekaterina Yu. , Novgorodtseva Oksana N. , Maksimovskiy Evgene A. , Ukhina Arina V. , Ishchenko Arcady V. , Bannov Alexander G.
Published: August 2023

This work is dedicated to the study of the treatment of multi-walled carbon nanotubes (MWCNTs) with dichromic acid. The dichromic acid was formed by dissolving different concentrations of CrO3 in water. The effect of the concentration of dichromic acid on the change in texture characteristics, elemental composition, defectiveness, graphitization degree, and surface chemistry of MWCNTs was investigated using various analytical techniques, such as transmission electron microscopy, energy-dispersive X-ray spectroscopy (EDX), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction, and X-ray photoelectron spectroscopy (XPS). Testing of MWCNTs as electrodes for supercapacitors in 3.5 M H2SO4 solution was carried out using cyclic voltammetry. A decrease in the average diameter of CNTs after treatment was found. The EDX and XPS showed that the oxygen content on the surface of MWCNTs increased after treatment with dichromic acid. The formation of Cr2O3 after treatment with dichromic acid was detected by XPS. High angle annular dark field scanning transmission electron microscopy was used to confirm the intercalation of the chromium-containing compound between graphene layers of MWCNTs after treatment with dichromic acid. It was found that two different types of MWCNTs showed diverse behavior after treatment. The highest specific capacitance of the MWCNTs after treatment was 141 F g−1 (at 2 mV s−1) compared to 0.3 F g−1 for the untreated sample.
Enhancing the Strength and Toughness of A356.2-0.15Fe Aluminum Alloy by Trace Mn and Mg Co-Addition
Authors: Cui Jie , Chen Jiayan , Li Yongbo , Luo Tianjiao
Published: August 2023

In the present work, microalloying is put forward to improve the microstructure and tensile properties of A356.2-0.15Fe (wt.%) alloy by the co-addition of trace Mn and Mg. A suitable Mn/Fe mass ratio of 0.5 is obtained for alloys with 0.15Fe. The yield strength, ultimate tensile strength, and elongation of the A356.2-0.15Fe alloy with an Mn/Fe ratio of 0.5 and containing 0.42 wt.% Mg is 179 MPa, 286 MPa, and 9.1%, respectively, which is acceptable for automotive wheel hub applications. Optical microscopy (OM), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and electron-probe microanalyzer (EPMA) methods are used to characterize the microstructure of the alloys. The results indicate that Mn addition promotes the transformation of the acicular β-Al5FeSi phase to the block-shaped α-Al(Fe, Mn)Si phase. The ratio of length/width of the Fe-rich phase in the alloy is reduced by 78.8% with an Mn/Fe ratio of 0.5 and containing 0.35 wt.% Mg, compared with that of the alloy without Mn addition and containing 0.35 wt.% Mg. The addition of Mg reduces the secondary dendrite arm spacing (SDAS) from 26.1 μm to 20.9 μm. The volume fraction of the precipitated Mg2Si phase in the alloy containing 0.42 wt.% Mg increases by 60% compared with that in the alloy containing 0.35 wt.% Mg. The morphology transformation of the Fe-rich phase, the reduction of SDAS, and the increase in volume fraction of precipitated Mg2Si phase comprehensively contribute to the improvement of A356.2-0.15Fe alloy. The microstructure evolution mechanism and the effect of microstructure on tensile properties are analyzed and discussed.
Stress Intensity Factor Solutions for Eccentric Annular External Cracks in Notched Round Bars under Tensile Loading
Authors: Toribio Jesús , Matos Juan-Carlos , González Beatriz , González Iván
Published: August 2023

In this paper, stress intensity factor (SIF) solutions of eccentric annular external cracks in elliptical notched round bars under tension loading have been obtained from 3D finite element analysis, along with their relation to the energy release rate obtained with the J-integral contour. The analysis variables have been the ligament diameter, its eccentricity, and the elliptical notch aspect ratio. The maximum SIF increases with the ligament eccentricity, the presence of the notch (compared to when the bar is smooth), and the elliptical notch axial semi-axis (for the same notch depth); it decreases with the ligament diameter. For external cracks, eccentricity induces bending of the bar subjected to tensile loading, which can produce partial and full contact of the crack surface, relevant phenomena in terms of the SIF value at the different points of the crack front.
On the Control of Elemental Composition, Macro-, and Microstructure of Directionally Solidified Additive Products from Nickel-Based Alloy
Authors: Fortuna Sergey , Gurianov Denis , Nikonov Sergey , Osipovich Kseniya , Kolubaev Evgeny
Published: August 2023

The present work establishes the influence of heat input and methods of heat removal at the wire-feed electron beam additive manufacturing (EBAM) process on the structure of an additive product made of a nickel-based alloy. The following printing approaches are considered: changes in heat input, 3D printing strategy, and heat removal conditions due to (1) heating of the substrate, (2) partial suppression of radiative heat dissipation, and (3) thermal insulation of the substrate. It is shown that epitaxial growth of dendrites occurs in each case. However, in the case of an increase in speed and a change in the 3D printing strategy, the directed dendritic growth is interrupted. Preheating of the substrate and subsequent maintenance of the temperature reached during the EBAM process, as well as partial suppression of the radiative component of heat removal, allow to obtain the most uniform directional structure.
Study on the Microstructure and High-Temperature Oxidation Performance of β-NiAl/γ′-Ni3Al Intermetallic Compounds Fabricated by Laser Metal Deposition
Authors: He Xun , Peng Xiao , Fang Juan
Published: August 2023

Four Ni-Al intermetallic compounds with the Al concentrations in range of 28 to 35 (in atomic percentage) have been fabricated by laser metal deposition (LMD) through mixing appropriate contents of pure Ni powder with pre-alloyed high-Al nickel aluminide powder. Ni-35Al and Ni-32Al are both composed of more than 45 vol.% β-NiAl matrix phase dispersing γ′-Ni3Al, while Ni-30Al and Ni-28Al consisted of worm-like, needle-like γ′-Ni3Al mainly and less than 37 vol.% β-NiAl. After 20 h oxidation in air at 1000 °C, the results of thermobalance, X-ray diffraction and scanning electron microcopy, indicated that Ni-35Al and Ni-32Al are more oxidation-resistant than the Ni-30Al and Ni-28Al. Because the first two can thermally grow an external Al2O3 scale but the second two form a duplex oxide scale consisting of outer NiAl2O4 layer and inner Al2O3 layer.
Imaging and Spectroscopic-Based Methods to Understand Cancer Metabolism and Biology
Authors: Madhu Basetti
Published: August 2023

The results of publications in PubMed with the MeSH terms “cancer”, “biology”, “imaging and cancer”, “metabolism” and “spectroscopy” are shown in Figure 1 in the form of a Venn diagram [...]