bluuebunny/crossref_metadata_2025 huggingface dataset:
The Clinical Significance of Serum Biomarkers of the Intestinal Barrier in Systemic Sclerosis: A Cross-Sectional Study
Authors: Stec Albert , Maciejewska Magdalena , Zaremba Michał , Paralusz-Stec Karolina , Michalska Milena , Rudnicka Lidia , Sikora Mariusz
Published: April 2023

Systemic sclerosis (SSc) is an immune-mediated connective tissue disease. Recent studies reported differences in the composition of intestinal microbiota (dysbiosis) in patients with SSc compared to nonsclerodermic subjects. Dysbiosis may disrupt the intestinal barrier, which leads to immunological activation via microbial antigen and metabolite translocation. The study aimed to assess the differences in intestinal permeability between SSc patients and controls and to examine the correlation between intestinal permeability and complications of SSc. The study comprised 50 patients with SSc and 30 matched subjects. Serum intestinal permeability markers: intestinal fatty acid binding protein, claudin-3, and lipopolysaccharides (LPS) were determined using an enzyme-linked immunosorbent assay. SSc patients had a significantly increased concentration of LPS compared to control subjects (232.30 [149.00–347.70] versus 161.00 [83.92–252.20] pg/mL, p < 0.05). The patients with shorter SSc duration (≤6 years) had an increased concentration of LPS and claudin-3 compared to the subgroup with longer disease length: LPS (280.75 [167.30–403.40] versus 186.00 [98.12–275.90] pg/mL, p < 0.05), and claudin-3 (16.99 [12.41–39.59] versus 13.54 [10.29–15.47] ng/mL, p < 0.05). The patients with esophageal dysmotility had a decreased LPS level compared to those without this complication (188.05 [102.31–264.40] versus 283.95 [203.20–356.30] pg/mL, p < 0.05). Increased intestinal permeability in SSc may exacerbate the course of the disease and increase the risk of developing complications. Lower LPS levels in SSc might be a hallmark of esophageal dysmotility.
Tourism Development and Italian Economic Growth: The Weight of the Regional Economies
Authors: Colacchio Giorgio , Vergori Anna Serena
Published: April 2023

This research aims to study the relationship between economic growth and the increase in the tourism sector in Italy. Unlike most of the literature, we use the value added in the main economic sectors involved in tourism activity as a proxy for tourism development. The use of the tourism value added allows us to analyze the effect of both international and domestic tourism on per capita GDP growth. The main working hypothesis we tested is whether the relationship between GDP growth and the expansion of the tourism sector is in any way influenced by the geographic area referenced and/or the time period considered. Accordingly, we conducted our analysis at both the national and subnational (cluster) levels, splitting the original sample into two equal subperiods (1997–2008 and 2009–2019). The panel VAR analysis shows that for the country as a whole, tourism growth depends on the past value of the economic growth rate, especially for the subperiod 2009–2019. The cluster analysis clarifies that these outcomes are strongly determined by the cluster that covers the wealthiest Italian regions.
The Effects of Tourism on Local Development in Protected Nature Areas: The Case of Three Nature Parks of the Sierra Morena (Andalusia, Spain)
Authors: Bahamonde-Rodríguez María , Šadeikaitė Giedrė , García-Delgado Francisco Javier
Published: April 2023

In rural spaces, new activities are developed to add to the traditional ones in the context of multifunctionality, considering the protection and enhancement of natural and cultural heritage, as in natural parks. These incorporate new recreational and tourist functions, understood as an instrument for local development. This research aims to study the relationships between tourism and local development in three natural parks (Sierra de Aracena and Picos de Aroche, Sierra Norte de Sevilla, and Sierra de Hornachuelos) in Andalusia (Spain). The research uses a mixed methodology consisting of, on the one hand, selective interviews with stakeholders focused on tourism and local development processes and, on the other, secondary data to analyse the repercussions on local development. The results show (1) the prevalence among the informants of the economic dimension in local development above the environmental and sociocultural dimensions; (2) the influence of declarations of protection and implementation of development policies on the growth of the tourist offer; (3) uneven tourism development in the different municipalities and natural parks; and (4) the limited effects of tourism on local development.
The Perception of the Impact of Land-Use on Small and Large Cities by Tourists Using p2p Platforms
Authors: Calvo Sara , Morales Andres , Del Arco Miguel Angel , Couto Gualter Manuel Medeiros do
Published: April 2023

In the literature, numerous impacts on local communities associated with the activity of online platforms for the intermediation of tourist accommodation have been described. Previous studies analyzed the perception associated with some of these impacts; however, the importance attributed by tourists using p2p platforms to the impact of the use of land has not been analyzed. Moreover, few studies have explored the different perceptions of these impacts on small and large cities. Therefore, this work, based on the information provided by 294 surveys associated with an online MOOC, analyzes the perception of users (tourists) of these p2p platforms on the impact of the use of land in small and large cities. The results have demonstrated that there is a great difference between the perception of respondents on this impact, with a worse perception of the use of p2p platforms by tourists who live in cities with a greater number of inhabitants.
Disparities in the Health Benefits of Urban Green/Blue Space: A Case Study from Shandong Province, China
Authors: Wang Xinrui , Lin Jian , Sun Xuemeng , Zhang Yutong , Wong Hiutung , Ouyang Libin , Liu Lin , Wu Longfeng
Published: April 2023

This study examined the relationships between different types of urban green and blue space (UGS/UBS) and self-reported health (SRH), and the disparities in the health benefits associated with them. Using data from a social survey in Shandong Province and multi-source data including remote sensing land use and vector polygons of parks from map service providers, we measured the proximity and coverage ratio of various UGS/UBS types. The Euclidean distance measures the proximity of homes to parks and rivers. The coverage ratio measures the total green space, forests, grassland, and freshwater. The health benefits were gauged by SRH. We found that the proximity to parks and rivers had a positive influence on the SRH of all the respondents. For the elderly, the proximity to parks and the coverage ratio of total green space and grassland within a 0.5 km circular buffer were significantly associated with SRH. The coverage ratio of the total green space and grassland both had positive relationships with the SRH of the high-income groups. The closer they were to rivers, the healthier the youth and females were. Our results suggest that urban planners should take the types of UGS/UBS into account to create a better living environment that optimally benefits residents’ SRH.
Understanding Carbon Emissions Reduction in China: Perspectives of Political Mobility
Authors: Li Zhichao , Liu Bojia
Published: April 2023

Climate change is one of the largest challenges facing mankind, and the question of how to reduce carbon emissions has raised extensive concern all over the world. However, due to the lack of mechanisms to explain the impact of political factors on environmental regulatory tools, the evaluation of carbon emissions reduction is insufficient in the majority of previous studies. How to better explore the path of carbon emissions reduction has become the key for China to achieve carbon neutralization as soon as possible. Based on a quasi-natural experiment regarding China’s carbon emission trading policy, this paper adopts a difference-in-differences model to address the impact of political mobility on China’s carbon emissions trading policy, and the selected pilot and non-pilot provinces of this policy in China enabled the model to be matched. Using a panel database with 30 provincial administrative units as the observation objects, the results show that China’s carbon emissions trading policy and the horizontal mobility experience of the provincial governors exert a significant positive effect on carbon emission reduction. Additionally, this study identifies a latent factor previously ignored by the existing literature: the correlation between political factors and carbon emissions. This verifies our theoretical hypothesis that officials transferred from the provincial level tend to have higher performance regarding carbon emission reduction. This paper also provides suggestions for the central government to further plan and implement carbon emission reduction policies and mobilize the incentives of local officials in environmental governance.
Influence of CYP2B6 Genotype on Methadone Dosage in Patients from the Methadone Maintenance Treatment (MMT) Program in Pereira, Colombia
Authors: Isaza Carlos , Castaño-Ramírez Oscar Mauricio , Vélez Juan Pablo , Henao Julieta , Beltrán-Angarita Leonardo , Sepúlveda-Arias Juan Carlos
Published: April 2023

Methadone treatment reduces the use of heroin and withdrawal symptoms; however, methadone is an expensive medication with a narrow safety margin. We compared the retention rates, persistence of heroin use, and quality of life of a group of patients undergoing conventional Methadone Maintenance Treatment (MMT) with a group for whom the CYP2B6 516G>T polymorphism was used in addition to the MMT to calculate the required methadone dose. Over 12 weeks, the retention rate, heroin usage, and quality of life of patients under conventional treatment (n = 34) were compared with those of patients for whom we used genetic markers to calculate methadone dosage (n = 38). At the end of the study, 26.4% of patients abandoned the program, and neither demographic nor clinical variables were associated with treatment adherence. Of the remaining patients, 16% of the control group and 8% of patients in the pharmacogenetic group reported heroin use, while both groups showed a 64% reduction in the use of cocaine/crack (no significant differences between the groups were found). Starting in the second week, the methadone dosage was lower among the patients for whom methadone was prescribed based on genotype. Although there were six individuals in the control group and three in the pharmacogenetic group with QTc intervals > 450 ms (a threshold that is considered dangerous), we did not find a relationship between the QTc interval and methadone dosage. There were no differences in the perception of quality of life between the two groups. The results of this pilot study suggest that concerning methadone therapy, the CYP2B6 genotype contributes to reduced effective doses and treatment costs.
Research on Leakage Prediction Calculation Method for Dynamic Seal Ring in Underground Equipment
Authors: Xu Xiaohui , Li Xin , Wang Fengtao , Xia Chunmiao
Published: April 2023

The leakage prediction calculation method for dynamic seal rings in underground equipment is presented in this paper. The framework of the method is given. The leakage prediction model is built. The non-Newtonian fluid interface element is brought in. The leakage prediction calculation method was developed based on the thermal–structural coupled method and the fluid–structural coupled method. A test is performed to validate the proposed method. It is proved that the film thickness of an O-ring made of nitrile rubber in pulling-in travel is thicker than that in pushing-out travel. The leakage of an O-ring made of fluororubber is larger than that of an O-ring made of nitrile rubber in the same environmental condition. The presented method is useful for predicting the sealing ability of dynamic seal rings in underground equipment. Evaluation costs will be reduced with the given leakage prediction calculation method.
3-(2-Chloro-5-methylphenoxy)propane-1,2-diol
Authors: Bredikhin Alexander A. , Bredikhina Zemfira A. , Samigullina Aida I. , Gubaidullin Aidar T.
Published: April 2023

3-(2-Chloro-5-methylphenoxy)propane-1,2-diol 1 is a possible precursor in the chiral beta blocker Bupranolol synthesis. Both racemic and single-enantiomeric samples of 1 were synthesized and characterized by single crystal XRD. The absolute configuration of an (S)-1 sample was determined by data refinement (the value of the Flack parameter is 0.03(4)). Hydrogen-bonded supramolecular synthons (SMS) were identified for both crystals. In rac-1, as well as in (S)-1 crystals, one of the two main SMS is the homochiral chain C11(5):21 (⋯O1–C1–C2–O2–H2⋯). The second of the two SMSs changes is the change of chiral environment. For rac-1, this is the heterochiral chain C33(9):{12/12/21}; (⋯O2–C2–C1–O1–H1⋯O′2–H′2⋯O″1–H″1⋯), in which molecules with different configurations alternate. In (S)-1 crystals, this is the homochiral chain C11(2):11 (⋯O1–H1⋯). The results obtained once again confirm the influence of the chiral environment on the crystallization of scalarly identical molecules.
Investigation and Characterization of Pickering Emulsion Stabilized by Alkali-Treated Zein (AZ)/Sodium Alginate (SA) Composite Particles
Authors: Kuang Ying , Xiao Qinjian , Yang Yichen , Liu Menglong , Wang Xiaosa , Deng Pengpeng , Wu Kao , Liu Yi , Peng Bo , Jiang Fatang , Li Cao
Published: April 2023

Pickering emulsions stabilized by food-grade colloidal particles have attracted increasing attention in recent years due to their “surfactant-free” nature. In this study, the alkali-treated zein (AZ) was prepared via restricted alkali deamidation and then combined with sodium alginate (SA) in different ratios to obtain AZ/SA composite particles (ZS), which were used to stabilize Pickering emulsion. The degree of deamidation (DD) and degree of hydrolysis (DH) of AZ were 12.74% and 6.58% respectively, indicating the deamidation occurred mainly in glutamine on the side chain of the protein. After the treatment with alkali, AZ particle size decreased significantly. Moreover, the particle size of ZS with different ratios was all less than 80 nm. when the AZ/SA ratio was 2:1(Z2S1) and 3:1(Z3S1), the three-phase contact angle (θo/w) were close to 90°, which was favorable for stabilizing the Pickering emulsion. Furthermore, at a high oil phase fraction (75%), Z3S1-stabilized Pickering emulsions showed the best long-term storage stability within 60 days. Confocal laser scanning microscope (CLSM) observations showed that the water-oil interface was wrapped by a dense layer of Z3S1 particles with non-agglomeration between independent oil droplets. At constant particle concentration, the apparent viscosity of the Pickering emulsions stabilized by Z3S1 gradually decreased with increasing oil phase fraction, and the oil-droplet size and the Turbiscan stability index (TSI) also gradually decreased, exhibiting solid-like behavior. This study provides new ideas for the fabrication of food-grade Pickering emulsions and will extend the future applications of zein-based Pickering emulsions as bioactive ingredient delivery systems.
Ultra-High Sensitivity and Temperature-Insensitive Optical Fiber Strain Sensor Based on Dual Air Cavities
Authors: Lu Zhiqi , Liu Changning , Li Chi , Ren Jie , Yang Lun
Published: April 2023

This study proposed an all-fiber Fabry–Perot interferometer (FPI) strain sensor with two miniature bubble cavities. The device was fabricated by writing two axial, mutually close short-line structures via femtosecond laser pulse illumination to induce a refractive index modified area in the core of a single-mode fiber (SMF). Subsequently, the gap between the two short lines was discharged with a fusion splicer, resulting in the formation of two adjacent bubbles simultaneously in a standard SMF. When measured directly, the strain sensitivity of dual air cavities is 2.4 pm/με, the same as that of a single bubble. The measurement range for a single bubble is 802.14 µε, while the measurement range for a double bubble is 1734.15 µε. Analysis of the envelope shows that the device possesses a strain sensitivity of up to 32.3 pm/με, which is 13.5 times higher than that of a single air cavity. Moreover, with a maximum temperature sensitivity of only 0.91 pm/°C, the temperature cross sensitivity could be neglected. As the device is based on the internal structure inside the optical fiber, its robustness could be guarantee. The device is simple to prepare, highly sensitive, and has wide application prospects in the field of strain measurement.
Research Progress on Factors Affecting Oil-Absorption Performance of Cement-Based Materials
Authors: Wang Dongli , Liu Siqing , Dong Bingqiang , Yuan Lili , Pan Huimin , Zhao Qingxin
Published: April 2023

With the wide application of petroleum resources, oil substances have polluted the environment in every link from crude oil extraction to utilization. Cement-based materials are the main materials in civil engineering, and the study of their adsorption capacity for oil pollutants can expand the scope of functional engineering applications of cement-based materials. Based on the research status of the oil-wet mechanism of different kinds of oil-absorbing materials, this paper lists the types of conventional oil-absorbing materials and introduces their application in cement-based materials while outlining the influence of different oil-absorbing materials on the oil-absorbing properties of cement-based composites. The analysis found that 10% Acronal S400F emulsion can reduce the water absorption rate of cement stone by 75% and enhance the oil-absorption rate by 62%. Adding 5% polyethylene glycol can increase the oil–water relative permeability of cement stone to 1.2. The oil-adsorption process is described by kinetic and thermodynamic equations. Two isotherm adsorption models and three adsorption kinetic models are explained, and oil-absorbing materials and adsorption models are matched. The effects of specific surface area, porosity, pore interface, material outer surface, oil-absorption strain, and pore network on the oil-absorption performance of materials are reviewed. It was found that the porosity has the greatest influence on the oil-absorbing performance. When the porosity of the oil-absorbing material increases from 72% to 91%, the oil absorption can increase to 236%. In this paper, by analyzing the research progress of factors affecting oil-absorption performance, ideas for multi-angle design of functional cement-based oil-absorbing materials can be obtained.
Multiscale Analysis of Functional Surfaces Produced by L-PBF Additive Technology and Titanium Powder Ti6Al4V
Authors: Gogolewski Damian , Zmarzły Paweł , Kozior Tomasz
Published: April 2023

The article discusses experimental studies assessing the possibility of mapping surfaces with a characteristic distribution of irregularities. Tests involved surfaces produced using the L-PBF additive technology, using titanium-powder-based material (Ti6Al4V). An evaluation of the resulting surface texture was extended to cover the application of a modern, multiscale analysis, i.e., wavelet transformation. The conducted analysis that involved using selected mother wavelet enabled production process errors and involved determining the size of resulting surface irregularities. The tests provide guidelines and enable a better understanding of the possibility of producing fully functional elements on surfaces, where morphological surface features are distributed in a characteristic way. Conducted statistical studies showed the advantages and disadvantages of the applied solution.
Porogen Concentration Effect on the Pore Structure and Properties Evolution of Polymer Monolith Based on Oligocarbonate Dimethacrylate OCM-2
Authors: Kovylin Roman S. , Yudin Vladimir V. , Shurygina Margarita P. , Fedoseev Victor B. , Chesnokov Sergey A. , Fedushkin Igor L. , Piskunov Alexandr V.
Published: April 2023

Porous polymer monolith materials of 2-mm thickness were obtained by visible light-induced radical polymerization of oligocarbonate dimethacrylate (OCM-2) in the presence of 1-butanol (10 to 70 wt %) as a porogenic additive. The pore characteristics and morphology of polymers were studied by mercury intrusion porosimetry and scanning electron microscopy. Monolithic polymers with both open and closed pores up to 100 nm in size are formed when the alcohol content in the initial composition is up to 20 wt %. The pore structure in such materials is a system of holes in the bulk of the polymer (hole-type pores). Open interconnected pores with a specific volume up to 2.22 cm3/g and modal pore size up to 10 microns are formed in the volume of the polymer with 1-butanol content of more than 30 wt %. Such porous monoliths are a structure of covalently bonded polymer globules (interparticle-type pores). The free space between the globules represents a system of open interconnected pores. In the transition region of 1-butanol concentrations (from 20 to 30 wt %), areas with both structures and intermediate frameworks, as well as honeycomb structures of polymer globules connected by bridges, are fixed on the polymer surface. It was found that the transition from one type of pore system to another is accompanied by a sharp change in the strength characteristics of the polymer. Approximation of experimental data using the sigmoid function made it possible to determine the concentration of the porogenic agent in the vicinity of which the percolation threshold is observed.
Relevant Choices Affecting the Fatigue Analysis of Ni-Ti Endovascular Devices
Authors: Berti Francesca , Brambilla Alma , Pennati Giancarlo , Petrini Lorenza
Published: April 2023

Ni-Ti alloys are widely used for biomedical applications due to their superelastic properties, which are especially convenient for endovascular devices that require minimally invasive insertion and durable effects, such as peripheral/carotid stents and valve frames. After crimping and deployment, stents undergo millions of cyclic loads imposed by heart/neck/leg movements, causing fatigue failure and device fracture that can lead to possibly severe consequences for the patient. Standard regulations require experimental testing for the preclinical assessment of such devices, which can be coupled with numerical modeling to reduce the time and costs of such campaigns and to obtain more information regarding the local state of stress and strain in the device. In this frame, this review aimed to enlighten the relevant choices that can affect the outcome of the fatigue analysis of Ni-Ti devices, both from experimental and numerical perspectives.
Effect of CaO, Al2O3, and MgO Supports of Ni Catalysts on the Formation of Graphite-like Carbon Species during the Boudouard Reaction and Methane Cracking
Authors: Kaporov Artem , Shtyka Oleksandr , Ciesielski Radoslaw , Kedziora Adam , Maniukiewicz Waldemar , Szynkowska-Jozwik Malgorzata , Madeniyet Yelubay , Maniecki Tomasz
Published: April 2023

The investigation of the course of the Boudouard reaction and methane cracking was performed over nickel catalysts based on oxides of calcium, aluminum, and magnesium. The catalytic samples were synthesized by the impregnation method. The physicochemical characteristics of the catalysts were determined using atomic adsorption spectroscopy (AAS), Brunauer–Emmett–Teller method analysis (BET), temperature-programmed desorption of ammonia and carbon dioxide (NH3- and CO2-TPD), and temperature-programmed reduction (TPR). Qualitative and quantitative identification of formed carbon deposits after the processes were carried out using total organic carbon analysis (TOC), temperature-programmed oxidation (TPO), X-ray diffraction (XRD), and scanning electron microscopy (SEM). The selected temperatures for the Boudouard reaction and methane cracking (450 and 700 °C, respectively) were found to be optimal for the successful formation of graphite-like carbon species over these catalysts. It was revealed that the activity of catalytic systems during each reaction is directly related to the number of weakly interacted nickel particles with catalyst support. Results of the given research provide insight into the mechanism of carbon deposit formation and the role of the catalyst support in this process, as well as the mechanism of the Boudouard reaction.
Preparation and Properties of Organically Modified Na-Montmorillonite
Authors: Qian Yan , Huang Zeen , Zhou Guantao , Chen Chenan , Sang Yuhang , Yu Zuolong , Jiang Legao , Mei Yuning , Wei Yunxiao
Published: April 2023

This study investigates the montmorillonite (MMT) content, rotational viscosity, and colloidal index of sodium montmorillonite (Na-MMT) as a function of the sodium agent dosage, reaction time, reaction temperature, and stirring time. Na-MMT was modified using different octadecyl trimethyl ammonium chloride (OTAC) dosages under optimal sodification conditions. The organically modified MMT products were characterized via infrared spectroscopy, X-ray diffraction, thermogravimetric analysis, and scanning electron microscopy. The results show that the Na-MMT with good properties (i.e., the maximum rotational viscosity and highest Na-MMT content with no decrease in the colloid index) was obtained at a 2.8% sodium carbonate dosage (measured based on the MMT mass), a temperature of 25 °C, and a reaction time of two hours. Upon organic modification of the optimized Na-MMT, OTAC entered the NA-MMT interlayer, and the contact angle was increased from 20.0° to 61.4°, the layer spacing was increased from 1.58 to 2.47 nm, and the thermal stability was conspicuously increased. Thus, MMT and Na-MMT were modified by the OTAC modifier.
Changes and Trends—Efficiency of Physical Blowing Agents in Polyurethane Foam Materials
Authors: Wang Haozhen , Yang Xiong , Liu Yingshu , Lin Lin
Published: April 2023

This work developed a novel method for measuring the effective rate of a PBA (physical blowing agent) and solved the problem that the effective rate of a PBA could not be directly measured or calculated in previous studies. The results show that the effectiveness of different PBAs under the same experimental conditions varied widely, from approximately 50% to almost 90%. In this study, the overall average effective rates of the PBAs HFC-245fa, HFO-1336mzzZ, HFC-365mfc, HFCO-1233zd(E), and HCFC-141b are in descending order. In all experimental groups, the relationship between the effective rate of the PBA, rePBA, and the initial mass ratio of the PBA to other blending materials in the polyurethane rigid foam, w, demonstrated a trend of first decreasing and then gradually stabilizing or slightly increasing. This trend is caused by the interaction of PBA molecules among themselves and with other component molecules in the foamed material and the temperature of the foaming system. In general, the influence of system temperature dominated when w was less than 9.05 wt%, and the interaction of PBA molecules among themselves and with other component molecules in the foamed material dominated when w was greater than 9.05 wt%. The effective rate of the PBA is also related to the states of gasification and condensation when they reach equilibrium. The properties of the PBA itself determine the overall efficiency, while the balance between the gasification and condensation processes of the PBA further leads to a regular change in efficiency with respect to w around the overall average level.
Intense Near-Infrared Light-Emitting NaYF4:Nd,Yb-Based Nanophosphors for Luminescent Solar Concentrators
Authors: Hong A-Ra , Shin Seungyong , Kang Gumin , Ko Hyungduk , Jang Ho Seong
Published: April 2023

In this study, we synthesized NaYF4-based downshifting nanophosphors (DSNPs), and fabricated DSNP-polydimethylsiloxane (PDMS) composites. Nd3+ ions were doped into the core and shell to increase absorbance at 800 nm. Yb3+ ions were co-doped into the core to achieve intense near-infrared (NIR) luminescence. To further enhance the NIR luminescence, NaYF4:Nd,Yb/NaYF4:Nd/NaYF4 core/shell/shell (C/S/S) DSNPs were synthesized. The C/S/S DSNPs showed a 3.0-fold enhanced NIR emission at 978 nm compared with core DSNPs under 800 nm NIR light. The synthesized C/S/S DSNPs showed high thermal stability and photostability against the irradiation with ultraviolet light and NIR light. Moreover, for application as luminescent solar concentrators (LSCs), C/S/S DSNPs were incorporated into the PDMS polymer, and the DSNP-PDMS composite containing 0.25 wt% of C/S/S DSNP was fabricated. The DSNP-PDMS composite showed high transparency (average transmittance = 79.4% for the visible spectral range of 380–750 nm). This result demonstrates the applicability of the DSNP-PDMS composite in transparent photovoltaic modules.
Phase-Field Insights into Hydrogen Trapping by Secondary Phases in Alloys
Authors: Bai Shijie , Liu Lin , Liu Chenyang , Xie Chao
Published: April 2023

Solid-state hydrogen storage is the best choice for balancing economy and safety among various hydrogen storage technologies, and hydrogen storage in the secondary phase might be a promising solid-state hydrogen storage scheme. In the current study, to unmask its physical mechanisms and details, a thermodynamically consistent phase-field framework is built for the first time to model hydrogen trapping, enrichment, and storage in the secondary phases of alloys. The hydrogen trapping processes, together with hydrogen charging, are numerically simulated using the implicit iterative algorithm of the self-defined finite elements. Some important results are attained: 1. Hydrogen can overcome the energy barrier under the assistance of the local elastic driving force and then spontaneously enter the trap site from the lattice site. The high binding energy makes it difficult for the trapped hydrogens to escape. 2. The secondary phase geometry stress concentration significantly induces the hydrogen to overcome the energy barrier. 3. The manipulation of the geometry, volume fraction, dimension, and type of the secondary phases is capable of dictating the tradeoff between the hydrogen storage capacity and the hydrogen charging rate. The new hydrogen storage scheme, together with the material design ideology, promises a viable path toward the optimization of critical hydrogen storage and transport for the hydrogen economy.
The Magnetoelastic Contribution to the Steel Internal Damping
Authors: Lo Conte Antonietta
Published: April 2023

In this paper, the steel internal damping due to both the thermoelastic and the magnetoelastic phenomena has been investigated through a formulation based on thermodynamical potential joints with a hysteretic damping model. With the aim of focusing on the temperature transient in the solid, a first configuration has been considered, which is characterized by a steel rod with an imposed alternating pure shear strain in which only the thermoelastic contribution was studied. The magnetoelastic contribution was then introduced in a further configuration, in which a steel rod in free motion was subjected to torsion on its ends in the presence of a constant magnetic field. A quantitative assessment of the influence of the magnetoelastic dissipation in steel has been computed according to the Sablik-Jiles model by giving a comparison between the thermoelastic and the prevailing magnetoelastic damping coefficients.
Frost-Resistant Rapid Hardening Concretes
Authors: Abdraimov Ilyas , Kopzhassarov Bakhadyr , Kolesnikova Inna , Akhmetov Daniyar Akbulatovich , Madiyarova Ilnura , Utepov Yelbek
Published: April 2023

This article presents the results of research conducted to determine the possibility of accelerating strength gain and enhancing the operational reliability of concrete. The study tested the effects of modern modifiers on concrete in order to select the composition of rapid hardening concrete (RHC) with better frost resistance characteristics. A basic composition of RHC grade C 25/30 was developed using traditional concrete calculations. Based on the analysis of previous studies by other authors, two basic modifiers (microsilica and calcium chloride (CaCl2)) and a chemical additive (a hyperplasticizer based on polycarboxylate esters) were selected. Then, a working hypothesis was adopted to find optimal and effective combinations of these components in the concrete composition. In the course of experiments, the most effective combination of additives for obtaining the best RHC composition was deduced by modeling the average strength values of samples in the early ages of curing. Further, RHC samples were tested for frost resistance in an aggressive environment at the ages of 3, 7, 28, 90, and 180 days to determine operational reliability and durability. The test results showed a real possibility of accelerating concrete hardening by 50% at the age of 2 days and achieving up to 25% strength gain by using both microsilica and calcium chloride (CaCl2). The best frost resistance indicators were observed in the RHC compositions with microsilica replacing part of the cement. The frost resistance indicators also improved with an increase in the amount of microsilica.
The Influence of a Blade-Guiding Fin on the Pneumatic Performance of an Axial-Flow Cooling Fan
Authors: Shu Hengtao , Chen Haizhou
Published: April 2023

An axial-flow cooling fan was taken as the research object in this paper, and a certain number of simulation models with different blade-guiding fin shapes were established. The methods of computational fluid dynamics (CFD), circumferential vorticity (CV) analysis and the response surface method (RSM) based on the design of experiments (DOE) method were all employed. The main external flow characteristics of the cooling fan, the blade surface pressure distribution, the static pressure efficiency and the fan power were obtained and compared. The relationships between the pneumatic performance and the fin shape parameters were subsequently investigated by the DOE method. The results obtained in this paper showed that a change in the fin height had a great influence on the pneumatic performance, while changes in its thickness had less of an influence. For the cooling fan studied in this paper, by adding reasonable structure-guiding fins onto the cooling fan blade, the static pressure efficiency was increased by a maximum of 7.6%. The research results have a good guiding significance regarding the srtructure design and optimization of axial cooling fans.
RaKShA: A Trusted Explainable LSTM Model to Classify Fraud Patterns on Credit Card Transactions
Authors: Raval Jay , Bhattacharya Pronaya , Jadav Nilesh Kumar , Tanwar Sudeep , Sharma Gulshan , Bokoro Pitshou N. , Elmorsy Mitwalli , Tolba Amr , Raboaca Maria Simona
Published: April 2023

Credit card (CC) fraud has been a persistent problem and has affected financial organizations. Traditional machine learning (ML) algorithms are ineffective owing to the increased attack space, and techniques such as long short-term memory (LSTM) have shown promising results in detecting CC fraud patterns. However, owing to the black box nature of the LSTM model, the decision-making process could be improved. Thus, in this paper, we propose a scheme, RaKShA, which presents explainable artificial intelligence (XAI) to help understand and interpret the behavior of black box models. XAI is formally used to interpret these black box models; however, we used XAI to extract essential features from the CC fraud dataset, consequently improving the performance of the LSTM model. The XAI was integrated with LSTM to form an explainable LSTM (X-LSTM) model. The proposed approach takes preprocessed data and feeds it to the XAI model, which computes the variable importance plot for the dataset, which simplifies the feature selection. Then, the data are presented to the LSTM model, and the output classification is stored in a smart contract (SC), ensuring no tampering with the results. The final data are stored on the blockchain (BC), which forms trusted and chronological ledger entries. We have considered two open-source CC datasets. We obtain an accuracy of 99.8% with our proposed X-LSTM model over 50 epochs compared to 85% without XAI (simple LSTM model). We present the gas fee requirements, IPFS bandwidth, and the fraud detection contract specification in blockchain metrics. The proposed results indicate the practical viability of our scheme in real-financial CC spending and lending setups.
Scaled Muth–ARMA Process Applied to Finance Market
Authors: Nascimento Abraão D. C. , Lima Maria C. S. , Bakouch Hassan , Qarmalah Najla
Published: April 2023

The analysis of financial market time series is an important source for understanding the economic reality of a country. We introduce a new autoregressive moving average (ARMA) process, the sMuth–ARMA model, which has the sMuth law as the marginal distribution and has one of its parameters as a proportion that can control amodal and unimodal behavior. We propose a procedure for obtaining the maximum likelihood estimators for its parameters and evaluate its performance for various link functions through Monte Carlo simulations. This research also addresses the issue of fluctuations in cryptocurrencies, which has played an increasingly important role in the global economy. An application to the range-based volatility of Tether (USDT) stablecoin prices shows the usefulness of the application of the proposed model over the Gaussian and other models reviewed.
Slipper Limpet (Crepidula fornicata) Shells Support In Vitro Osteogenesis of Human Adipose-Derived Stem Cells
Authors: De Mori Arianna , Alasa Umoru Junior , Mühlhölzl Alex , Blunn Gordon
Published: April 2023

This study aimed to investigate a cost-effective alternative to man-made calcium phosphate ceramics for treating bone defects. The slipper limpet is an invasive species in European coastal waters, and its shells composed of calcium carbonate could potentially be a cost-effective source of bone graft substitutes. This research analyzed the mantle of the slipper limpet (Crepidula fornicata) shells to enhance in vitro bone formation. Discs machined from the mantle of C. fornicata were analyzed using scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS), X-ray crystallography (XRD), Fourier-transform infrared spectroscopy (FT-IR) and profilometry. Calcium release and bioactivity were also studied. Cell attachment, proliferation, and osteoblastic differentiation (RT-qPCR and alkaline phosphatase activity) were measured in human adipose-derived stem cells grown on the mantle surface. The mantle material was mainly composed of aragonite and showed a sustained Ca2+ release at physiological pH. In addition, apatite formation was observed in simulated body fluid after three weeks, and the materials supported osteoblastic differentiation. Overall, our findings suggest the mantle of C. fornicata shows potential as a material for fabricating bone graft substitutes and structural biomaterials for bone regeneration.
The Effect of Steroid and Mannitol Combination Treatment on Postoperative Rehabilitation of Multiple Metacarpal Bone Fractures
Authors: Choi Jangyoun , Seo Hye Jin , Shin Jongweon , Byun Jun-Hee , Jung Sung No
Published: April 2023

Background and Objectives: The expedient resolution of postoperative soft tissue edema is particularly important in hand surgery. Prolonged edema and pain become an obstacle to postoperative rehabilitation, delay return to daily life, and in severe cases, lead to a permanent decrease in range of motion. Based on the common physiology between postoperative hand swelling and complex regional pain syndrome (CRPS), we sought to determine if postoperative mannitol and steroid administration to multiple metacarpal bone fracture patients effectively reduces hand swelling and pain and is beneficial for hand rehabilitation. Materials and Methods: From March 2015 to February 2019, 21 patients who received closed pinning for multiple metacarpal fractures were included in a retrospective cohort study. The control group (n = 11) underwent a routine recovery, while the treatment group (n = 10) received dexamethasone and mannitol injections for five days postoperatively. Serial changes in the degree of pain and fingertip-to-palm distance (FPD) were measured in both groups. The duration from surgery to the initiation of rehabilitation and time to full grip was also compared. Results: Compared to the control, the treatment group showed a faster alleviation of pain scores from the postoperative fifth day (2.91 versus 1.80, p = 0.013), and faster recovery of FPD from postoperative two weeks (3.27 versus 1.90, p = 0.002). Time to physical therapy initiation (6.73 versus 3.80 days, p = 0.002) and full grip achievement (42.46 versus 32.70 days, p = 0.002) were also faster in the treatment group. Conclusions: The steroid-mannitol combination treatment for multiple metacarpal bone fracture patients in the acute postoperative phase promoted the reduction of hand edema and pain, leading to the earlier initiation of physical therapy, rapid improvement in joint motion, and faster achievement of full grip.
Addressing the Challenges in the Diagnosis and Management of Pediatric Wilson’s Disease—Case Report and Literature Review
Authors: Ungureanu Irene Maria , Iesanu Mara Ioana , Boboc Catalin , Cosoreanu Vlad , Vatra Lorena , Kadar Anna , Ignat Evelina Nicoleta , Galos Felicia
Published: April 2023

Wilson’s disease (WD) is an autosomal recessive disorder, in which the metabolism of copper is affected by metal accumulation in several organs that causes gradual organ degeneration. Since Wilson’s initial description of WD over a century ago, there have been significant improvements in understanding and managing the condition. Nevertheless, the ongoing gap between the onset of symptoms and diagnosis highlights the difficulties in identifying this copper overload disorder early. Despite being a treatable condition, detecting WD early remains a challenge for healthcare professionals at all levels of care, likely due to its rarity. The key challenge is, therefore, to educate physicians on how to identify atypical or infrequent symptoms of WD, prompting them to consider the diagnosis more carefully. The purpose of our review is to draw attention to the difficulties associated with diagnosing pediatric WD, starting from our personal experience of a complex case and then examining relevant literature. In summary, the diagnosis of WD in children is intricate and requires a heightened level of suspicion to identify this infrequent condition. A thorough evaluation by a multidisciplinary team of physicians, along with genetic testing, histopathologic examination, and specialized imaging studies, may be necessary to confirm the diagnosis and guide treatment.
Sn and Ge Complexes with Redox-Active Ligands as Efficient Interfacial Membrane-like Buffer Layers for p-i-n Perovskite Solar Cells
Authors: Akbulatov Azat F. , Akyeva Anna Y. , Shangin Pavel G. , Emelianov Nikita A. , Krylova Irina V. , Markova Mariya O. , Labutskaya Liliya D. , Mumyatov Alexander V. , Tuzharov Egor I. , Bunin Dmitry A. , Frolova Lyubov A. , Egorov Mikhail P. , Syroeshkin Mikhail A. , Troshin Pavel A.
Published: April 2023

Inverted perovskite solar cells with a p-i-n configuration have attracted considerable attention from the research community because of their simple design, insignificant hysteresis, improved operational stability, and low-temperature fabrication technology. However, this type of device is still lagging behind the classical n-i-p perovskite solar cells in terms of its power conversion efficiency. The performance of p-i-n perovskite solar cells can be increased using appropriate charge transport and buffer interlayers inserted between the main electron transport layer and top metal electrode. In this study, we addressed this challenge by designing a series of tin and germanium coordination complexes with redox-active ligands as promising interlayers for perovskite solar cells. The obtained compounds were characterized by X-ray single-crystal diffraction and/or NMR spectroscopy, and their optical and electrochemical properties were thoroughly studied. The efficiency of perovskite solar cells was improved from a reference value of 16.4% to 18.0–18.6%, using optimized interlayers of the tin complexes with salicylimine (1) or 2,3-dihydroxynaphthalene (2) ligands, and the germanium complex with the 2,3-dihydroxyphenazine ligand (4). The IR s-SNOM mapping revealed that the best-performing interlayers form uniform and pinhole-free coatings atop the PC61BM electron-transport layer, which improves the charge extraction to the top metal electrode. The obtained results feature the potential of using tin and germanium complexes as prospective materials for improving the performance of perovskite solar cells.
Research and Application of the Original Position Statistical Distribution Analysis Method for Non-Metallic Inclusions in P91 Steel
Authors: Zhu Changwang , Yang Lixia , Zhao Lei , Ma Yue , Wang Yang , Shen Xuejing , Wang Haizhou
Published: April 2023

Heat-resistant P91 martensitic steel is used to produce high-temperature steam pipelines in (ultra) critical power plants. However, non-metallic inclusions are inevitably produced in the metallurgical process. The type, composition, morphology, quantities, size and distribution of these inclusions have significant influences on the properties of materials. The present work developed an original position statistical distribution analysis method to characterize non-metallic inclusions in P91 steel based on scanning electron microscopy (SEM) with energy-dispersive spectroscopy (EDS). Two samples from P91 steel pipes fabricated by different processes were examined. The non-metallic inclusions in these samples could be divided into spherical oxides, strand-shaped oxides, spherical sulfides, spherical oxygen–sulfur compounds, strip sulfides and other inclusions. The amount, proportional area, particle sizes, original positions and statistical distribution results of non-metallic inclusions in different processed samples were assessed, and the causes and effects of these inclusions were analyzed. This novel method could provide diversified information on inclusions, which is helpful for the improvement of metallurgical processes and service performance evaluations.
Treatment of Acidic Solutions Containing As(III) and As(V) by Sulfide Precipitation: Comparison of Precipitates and Sulfurization Process
Authors: Xu Hui , Wang Yunyan , Yao Liwei , Ke Yong , Luo Yongjian , Zhang Limin , Du Jiali , Yu Lin , Cao Junjie , Min Xiaobo
Published: April 2023

Sulfide precipitation has been widely applied to remove arsenic from acidic wastewater containing As(III) and As(V), due to its simple process and high efficiency. However, the characteristics and composition of the precipitates are also of importance for its further treatment and disposal. To explore the characteristics of elemental S formed by reduction and the combined form of the generated S and As2S3, the characteristics of precipitates sulfurized from As(III) and As(V) and the effects of temperature, the S(-II) to As ratio (S/As), Cl− concentration (cCl−), and the volume fraction of H2SO4 (φH2SO4(v)) on the sulfurization of As(III) and As(V) were investigated in detail. The results showed that the contents of As and S were 60.37% and 39.73% in precipitate-As(III), while they accounted for 47.46% and 52.64% in precipitate-As(V); both precipitate-As(III) and precipitate-As(V) were mainly composed of amorphous As2S3, while the latter contained elemental S. Temperature and S(-II)/As(III) slightly affected the sulfurization process of As(III), while for As(V), as the temperature increased, the content of As2S3 in precipitate-As(V) increased significantly. Additionally, with the S(-II)/As(V) increasing, the content of A2S3 increased continuously. This study provides a further clarification of the specific composition and structure of the complex precipitates of arsenic sulfide, which will benefit the efficient stabilization of the arsenic sulfide sludge.