bluuebunny/crossref_metadata_2025 huggingface dataset:
Optimizing Portfolio Risk of Cryptocurrencies Using Data-Driven Risk Measures
Authors: Bowala Sulalitha , Singh Japjeet
Published: September 2022

Portfolio risk management plays an important role in successful investments. Portfolio standard deviation, value-at-risk, expected shortfall, and maximum absolute deviation are widely used portfolio risk measures. However, the existing portfolio risk measures are vulnerable to larger skewness and kurtosis of the asset returns. Moreover, the traditional assumption of normality of the portfolio returns leads to the underestimation of portfolio risk. Cryptocurrencies are a decentralized digital medium of exchange. In contrast to physical money, cryptocurrency payments exist purely as digital entries on an online ledger called blockchain that describe specific transactions. Due to the high volume and high frequency of cryptocurrency transactions, risk forecasting using daily data is not enough, and a high-frequency analysis is required. High-frequency data reveal a very high excess kurtosis and skewness for returns of cryptocurrencies. In order to incorporate larger skewness and kurtosis of the cryptocurrencies, a data-driven portfolio risk measure is minimized to obtain the optimal portfolio weights. A recently proposed data-driven volatility forecasting approach with daily data are used to study risk forecasting for cryptocurrencies with high-frequency (hourly) big data. The paper emphasizes the superiority of portfolio selection of cryptocurrencies by minimizing the recently proposed risk measure over the traditional minimum variance portfolio.
Research on Supervision Mechanism of Big Data Discriminatory Pricing on the Asymmetric Service Platform—Based on SD Evolutionary Game Model
Authors: Xu Bing , Li Qin
Published: September 2022

Big data discriminatory pricing behavior of service platforms frequently occurs, which affects the legitimate rights and interests of consumers as well as the healthy development of the platform economy. The SD (System Dynamics) evolutionary game model characterizing the game relationship of a big platform, small platform, and government is constructed together with its equilibrium solutions in order to analyze the regulatory dilemma and governance mechanism against big data discriminatory pricing of service platforms. This paper finds that government punishment on the behavior of big data discriminatory pricing plays a decisive role. When the government punishment is large enough, both platforms tend towards fair pricing; when the government punishment is insufficient, the big platform always tends towards discriminatory pricing. The supply chain of the service platform falls into the regulatory dilemma of big data discriminatory pricing behavior. Due to the hidden characteristics of big data discriminatory pricing and technical challenges in authentication and proof, a third party is introduced for supervision, and an SD evolutionary game model with a collaborative supervision mechanism of the government and the third party is constructed. The results show that positive supervision of the third party can effectively regulate the big data discriminatory pricing behavior of the big platform, which has specific implications for the design of the supervision mechanism against big data discriminatory pricing of service platforms.
Can We Witness the (Re)making of a Pidgin in Real Time? Contact in the Russian–Chinese Border Area
Authors: Fedorova Kapitolina
Published: September 2022

The empirical focus of this paper is on the interethnic communication along the Russian–Chinese border. Language contact in this area has a long history; in the 18th century, it resulted in a contact variety, the so-called Kyakhta language, or Russian–Chinese pidgin, which fell into disuse after a century. The contact has resumed recently, and we are currently witnessing the emergence of new contact varieties in real time in the area. The reported research aimed to study language contact as a social practice and gain access not only to linguistic facts but also to speakers’ perceptions of them revealed in interviews and conversations. The discussion is based on field data collected between 2008 and 2010 in Zabaykalskiy Krai in Russia and in the province of Inner Mongolia in China. The study reveals different non-standard varieties emerging through interethnic interactions in the border area, and uncovers linguistic features that were typical of Russian–Chinese pidgin (and impossible in Standard Russian) being ‘reinvented’ now both in the Chinese ethnolect of Russian and in some extreme forms of foreigner talk employed by Russian speakers professionally involved in regular communication with Chinese speakers. The paper stresses the role of the professionalization of communication for pidgin development.
(Diaqua)hexakis(4,4,4-trifluoro-1-(1-methyl-1H-pyrazol-4-yl)butane-1,3-dionato-κ2O,O’)(μ-(1,4-dioxane))digadolinium (III), Solvate with Two Molecules of 1,4-Dioxane
Authors: Taydakov Ilya V. , Belousov Yury A. , Metlin Mikhail T. , Gontcharenko Victoria E.
Published: September 2022

A binuclear gadolinium (III) complex was obtained through the interaction of GdCl3·6H2O, 4,4,4-trifluoro-1-(1-methyl-1H-pyrazol-4-yl)butane-1,3-dione and NaOH in MeOH solution. Molar ration of reagents equal to 1:3:3 was used. Upon recrystallization of wet 1,4-dioxane, an intermediate hydrated complex formed stable crystalline solvate with the composition [(Gd2(L)3(H2O))2(C4H8O2)]•2(C4H8O2). The structured of complex was established by single crystal XRD experiment. Furthermore, some photophysical properties of the complex were measured. Thus, the energy of the first exited triplet state for the diketonate ligand was found to be 22400 cm−1, which makes 4,4,4-trifluoro-1-(1-methyl-1H-pyrazol-4-yl)butane-1,3-dione a promising ligand for the preparation of highly luminescent Eu3+ and Sm3+ complexes.
Assembly of Sn(IV)-Porphyrin Cation Exhibiting Supramolecular Interactions of Anion···Anion and Anion···π Systems
Authors: Kim Hee-Joon
Published: September 2022

Trans-diaqua[meso-tetrakis(4-pyridyl)porphyrinato]Sn(IV) dinitrate complexes were assembled in a two-dimensional manner via hydrogen bonding between aqua ligands and pyridyl substituents. Interestingly, this supramolecular assembly was accompanied by unconventional noncovalent interactions, such as anion···anion and anion···π interactions, which were confirmed by X-ray crystallographic analysis. Two nitrate anions close to 2.070 Å were constrained in a confined space surrounded by four hydrogen-bonded Sn(IV)-porphyrin cations. The nitrate anion was also 3.433 Å away from the adjacent pyrrole ring, and the dihedral angle between the two mean planes was estimated to be 7.39°. The preference of the anion···π interaction was related to the electron-deficient π-system owing to the high-valent Sn(IV) center and cationic nature of the porphyrin complex. These two unconventional noncovalent interactions played an important role in the formation of a one-dimensional array with pairs of Sn(IV)-porphyrin cation and nitrate anion.
Deep Drawing Behavior of Metal-Composite Sandwich Plates
Authors: Hwang Shun-Fa , Li Yu-Ren
Published: September 2022

The deep drawing behavior of metal-composite sandwich plates, or fiber-metal laminates, in which aluminum or steel sheets are used as the face layer and composite materials are used as the core layer, is discussed in this work to find the workpieces without fractures and wrinkles. Two types of aluminum, 1050 and 6061, are considered their suitability as face sheets. The preheat effect of aluminum 6061 on formability is also investigated. When steel sheets are used, the effect of blank-holder pressure is included. In addition, to understand the deformation of fabric composite, pure composite laminates are deep drawn. The results of composite laminates show that after drawing, the weft and warp lines are shorter than the other radial lines, causing the specific deformed shape and the variation of the fiber intersection angle. For Al-composite sandwich plates, fractures and wrinkles are easy to occur. Even though the fracture and wrinkle conditions are released with the increase in preheating temperature of aluminum 6061, it may be not enough. For the deep drawing of the steel-composite sandwich plates, in which fractures are avoided, the increase of blank-holder pressure could reduce the wrinkle number. Hence, good quality workpieces without fracture and wrinkle could be obtained when the blank-holder pressure is high enough.
Synergistic Effect of Polycarboxylate Superplasticiser and Protein Retarders in Cementitious Materials Containing Na- Montmorillonite: Effect of Addition Methods
Authors: Tian Zhenhe , Ren Jun , Li Hao , Wang Xusheng , Feng Yang , Xiong Wei , Yang Jialing , Xu Shengye , Ren Zengle
Published: September 2022

Polycarboxylate superplasticiser (PCE) is notably sensitive towards Na-Montmorillonite (Na-Mmt), an impurity generated from the manufacturing of concrete aggregate due to the chemical intercalation and poor surface adsorption. In order to improve the poor compatibility of PCE, the protein-based retarders were applied as the sacrificial agents, and its synergetic effects in cementitious materials containing Na-Mmt were investigated. The protein-based retarders were applied as the sacrificial agents and its synergetic effects in cementitious materials containing Na-Mmt were investigated. In addition to test rheology, minislump, and setting time, the adsorption behaviour and intercalation were characterised via Total Organic Carbon, X-ray photoelectron spectroscopy, and X-ray diffraction. The results revealed that the incorporation of protein-retarders improved the performance of PCE in terms of workability, and the rheological behaviour of cement with Na-Mmt. Moreover, compared to simultaneous addition, the application of separate addition further increased the workability and improved workability retention, with best dispersion performance obtained by prior adding the retarders, which could be due to the lessened intercalation between the layers of Na-Mmt.
Bacterial Carbonate Precipitation Using Active Metabolic Pathway to Repair Mortar Cracks
Authors: Raza Ali , Khushnood Rao Arsalan
Published: September 2022

A study was conducted to check the efficacy of microbial pathways for calcite precipitation to heal pre-existing cracks in mortar. In this experiment, realistic cracks of varying widths were induced on a mortar sample. Different repair methods were applied to a total of 22 mortar samples. Twelve cracked mortar samples with average crack widths ranging from 0.29 to 1.08 mm were subjected to biodeposition treatment using calcium lactate as a food source. The remaining ten samples were split into two groups: five cracked mortar samples were exclusively exposed to the bacterial solution, while the remaining five samples were immersed in distilled water. Digital image processing was used to extract the crack characteristics before and after the repair application. During several repair cycles, image processing was used to track healing. Further, these repaired mortar samples underwent examination for water permeability, ultra-sonic examination, and examination for recovered compressive strength. A forensic examination of the healing product in terms of morphology and elemental composition was conducted using RAMAN, XRD, SEM-EDS, and TGA. The water permeability of the repaired mortar sample using biodeposition with Ca-lactate was dramatically reduced, but samples treated with bacterial solution and distilled water did not exhibit any significant reduction. Complete crack healing was observed when using Ca-lactate as a food source for microbial repair. The forensic analysis confirmed the presence of calcite in healing precipitates
A Tailored Preparation Method of Variable Strength for Ultra-High-Strength Steel Sheet and Mapping Mechanism between Process and Property
Authors: Quan Guo-Zheng , Yu Yan-Ze , Zhang Yu , Zhang Yu-Qing , Xiong Wei
Published: September 2022

The spatiotemporal phase transformation during hot stamping would considerably effect the microstructure and mechanical properties of steels. In order to manufacture hot-stamping components of ultra-high-strength steel with tailored mechanical properties, the effect of the quenching time and the temperature of the die on the phase-transformation characteristics and mechanical property of ultra-high-strength steel was deeply studied. A finite element (FE) model coupled with a thermomechanical phase was employed to perform a succession of simulations for hot stamping corresponding to different quenching times and the temperatures of die, and the corresponding hot stamping experiments were performed. The 3D mapping surfaces of the temperature; quenching time; and three microstructures, namely austenite, bainite, and martensite, were constructed, and the mapping relationships in such surfaces were further explained by microstructural observations. Subsequently, based on the test results of the mechanical properties, the relationship curves of hardness and tensile strength, hardness, and elongation at break were fitted respectively, and then the 3D mapping surfaces were constructed for hardness, tensile strength, and elongation at break, which varied with the temperature die and quenching time. Finally, the quenching parameters of the automobile B-pillar were designed according to the constructed mapping relationship, and the hot-stamping FE simulation of the automobile B-pillar was developed. The result shows that those constructed mapping surfaces are helpful for adjusting the local mechanical property of the steels by designing the parameters.
Evaluation of Recycled Spent Coffee Material Treated with Animal Glue, Starch, and Red Clay as Acid Materials
Authors: Park Sung-Sik , Woo Seung-Wook , Lee Jung-Shin , Yun Young-Mook , Lee Dong-Eun
Published: September 2022

Annual coffee consumption has increased to 10 million tons. Of the coffee consumed, 65% is discarded as spent coffee grounds (SCG). However, most SCG are buried in the ground as organic waste. The more coffee consumption increases, the more land is used for disposing of spent coffee. SCG recycling has gotten considerable attention as a solution involved in these issues. The construction community has studied means and methods to recycle SCG as construction materials, such as bricks, subgrade fillers, thermal insulators, etc. This paper presents a new method, which recycles SCG as a construction material, maximally using its acidity. The SCG were hardened with natural binders (i.e., animal glue (AG) and starch (S)) and red clay (RC). The SCG mixtures were pressed with 2 MPa in a cylindrical mold and cured for 7 days. Then, the strength, durability, and pH tests were measured. The AG- and RC-treated SCG sample, which outputs 1933 kPa of strength and a 4.9 pH value, is identified as the optimal sampling method among the acid materials produced in this study. The optimal sample decreases the pH to approximately 7 of water where 68% weight of Ordinary Portland cement was soaked in.
Optimization and Predictive Modeling of Reinforced Concrete Circular Columns
Authors: Bekdaş Gebrail , Cakiroglu Celal , Kim Sanghun , Geem Zong Woo
Published: September 2022

Metaheuristic optimization techniques are widely applied in the optimal design of structural members. This paper presents the application of the harmony search algorithm to the optimal dimensioning of reinforced concrete circular columns. For the objective of optimization, the total cost of steel and concrete associated with the construction process were selected. The selected variables of optimization include the diameter of the column, the total cross-sectional area of steel, the unit costs of steel and concrete used in the construction, the total length of the column, and applied axial force and the bending moment acting on the column. By using the minimum allowable dimensions as the constraints of optimization, 3125 different data samples were generated where each data sample is an optimal design configuration. Based on the generated dataset, the SHapley Additive exPlanations (SHAP) algorithm was applied in combination with ensemble learning predictive models to determine the impact of each design variable on the model predictions. The relationships between the design variables and the objective function were visualized using the design of experiments methodology. Applying state-of-the-art statistical accuracy measures such as the coefficient of determination, the predictive models were demonstrated to be highly accurate. The current study demonstrates a novel technique for generating large datasets for the development of data-driven machine learning models. This new methodology can enhance the availability of large datasets, thereby facilitating the application of high-performance machine learning predictive models for optimal structural design.
Electrolytic Recovery of Metal Cobalt from Waste Catalyst Pickling Solution
Authors: Chou Yi-Sin , Kan Chin-Hsiang , Devi Nitika , Chen Yong-Song
Published: September 2022

Terephthalic acid production plant uses liquid cobalt–manganese bromide as a catalyst. The waste catalyst is burned with exhaust gas and accumulated in fly ash, which is further pickled and impregnated with a sulfuric acid solution. The resultant solution is rich in cobalt and manganese metal ions with few metal impurities from other petroleum raw materials. An electrochemical reduction method is used to recover cobalt metal from the waste catalyst fly ash pickling solution of terephthalic acid. Various steps have been taken to remove impurities and extract and separate the required pure cobalt metal solution. Afterward, the process of electrolytic reduction smelting is conducted. Variables investigated include current density, electrolyte pH, electrode materials, and electrolytic cell diaphragms, among several others. Results show that the product purity can reach up to 99.84% for the electrolyte feed composition of 21.4 g L−1 Co, 38.2 g L−1 Na, and 2.02 g L−1 Mg.
Study on Mechanical Properties and Weakening Mechanism of Acid Corrosion Lamprophyre
Authors: Guo Jun , Mi Xincheng , Feng Guorui , Qi Tingye , Bai Jinwen , Wen Xiaoze , Qian Ruipeng , Zhu Linjun , Guo Xingchen , Yu Luyang
Published: September 2022

In order to study the weakening mechanism and mechanical behaviors of hard lamprophyre of Carboniferous Permian coal-bearing strata in China’s mining area, lamprophyre samples were subjected to static rock dissolution experiments with pH values of 0, 2, and 4. The acid corrosion mechanism of lamprophyre was revealed from the weight changes of samples, characteristics of solution ion concentration, and macro-mechanical properties. The experimental results show that reaction occurred between lamprophyre and acid solution. With the increasing concentration of H+, the reaction was more intense, the degree of acid etching was higher, and the weight loss was greater. The internal damage induced by acid etching results in the slow extension of the compaction stage of stress–strain curve of uniaxial compression, and the obvious deterioration of mechanical properties of the lamprophyre. The uniaxial compressive strength of the lamprophyre in the dry state is 132 MPa, which decreased to 39 MPa under the acid etching condition, showing significant mudding characteristics. Dolomite (CaMg(CO3)2 with 19.63%) and orthoclase (KAlSi3O8 with 31.4%) in lamprophyre are the major minerals constituents involved in acidification reaction. Photomicrograph recorded from SEM studies reveals that the dissolution effect was directly related to the concentration of H+ in the solution. The dissolution effect was from the surface to the inside. The small dissolution pores became larger and continuously expanded, then finally formed a skeleton structure dominated by quartz. The content of K+, Ca2+, and Mg2+ in the solution after acid etching reaction indicates that the acidified product of orthoclase is colloidal H2SiO3, which adhered to the surface of samples during acid etching and hinders the further acidification of minerals. The dissolution of dolomite and orthoclase under acidic conditions directly leads to the damage of their structure and further promotes the water–rock interaction, which is the fundamental reason for the weakening of the mechanical properties of lamprophyre.
Distribution of Iron Nanoparticles in Arrays of Vertically Aligned Carbon Nanotubes Grown by Chemical Vapor Deposition
Authors: Okotrub Alexander V. , Gorodetskiy Dmitriy V. , Gusel’nikov Artem V. , Kondranova Anastasiya M. , Bulusheva Lyubov G. , Korabovska Mariya , Meija Raimonds , Erts Donats
Published: September 2022

Arrays of aligned carbon nanotubes (CNTs) are anisotropic nanomaterials possessing a high length-to-diameter aspect ratio, channels passing through the array, and mechanical strength along with flexibility. The arrays are produced in one step using aerosol-assisted catalytic chemical vapor deposition (CCVD), where a mixture of carbon and metal sources is fed into the hot zone of the reactor. Metal nanoparticles catalyze the growth of CNTs and, during synthesis, are partially captured into the internal cavity of CNTs. In this work, we considered various stages of multi-walled CNT (MWCNT) growth on silicon substrates from a ferrocene–toluene mixture and estimated the amount of iron in the array. The study showed that although the mixture of precursors supplies evenly to the reactor, the iron content in the upper part of the array is lower and increases toward the substrate. The size of carbon-encapsulated iron-based nanoparticles is 20–30 nm, and, according to X-ray diffraction data, most of them are iron carbide Fe3C. The reasons for the gradient distribution of iron nanoparticles in MWCNT arrays were considered, and the possibilities of controlling their distribution were evaluated.
Microwave Polarization Sensing for Dielectric Materials Based on a Twisted Dual-Layer Meta-Surface
Authors: Xiao Hong , Yan Sen , Chen Juan
Published: September 2022

A microwave sensor is proposed based on a chiral twisted dual-layer meta-surface. Elliptical angle and polarization rotation angle are used to characterize the different dielectric constants of materials. The dielectric films consisting of polydimethylsiloxane and barium titanate with volume fractions 0%, 10%, 15%, 20% are prepared and tested for a proof of concept. The measured results show that the Q factors of polarization rotation angle and elliptical angle peak are 11.85 when the volume fraction of barium titanate is 20%, which is 75.5% higher than 6.75 of the transmission resonance peak, and the figures of merit of the polarization rotation angle and elliptical angle peak are 0.99 and 0.86, which are 73.7% and 50.9% higher than the 0.57 of transmission resonance, respectively. Compared to the resonance sensing method, polarization sensing not only has a better Q factor and figure of merit while maintaining similar sensitivity, but also obtains more characterization information due to the double-parameter sensing, which provide a new idea for the development of high-sensitivity microwave sensors.
Novel Nd-N/TiO2 Nanoparticles for Photocatalytic and Antioxidant Applications Using Hydrothermal Approach
Authors: Alam Mir Waqas , Khalid N. R. , Naeem Sumaira , Niaz N. A. , Ahmad Mir Tanveer , Nahvi Insha , Souayeh Basma , Zaidi Noushi
Published: September 2022

In this study, photocatalysis was employed to degrade a wastewater pollutant (AB-29 dye) under visible light irradiation. For this purpose, nitrogen (N)- and neodymium (Nd)-doped TiO2 nanoparticles were prepared using the simple hydrothermal method. X-ray diffraction (XRD) revealed an anatase phase structure of the Nd-N/TiO2 photocatalyst, whereas properties including the surface morphology, chemical states/electronics structure and optical structure were determined using transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and UV–visible (UV–vis.) and photoluminescence (PL) spectroscopies. Photocatalytic testing of the prepared nanomaterials was performed to remove acid blue-29 (AB-29) dye under visible-light exposure. The prepared Nd-N/TiO2 nanoparticles demonstrated a superior photocatalytic activity and the decolorization efficiency was about 92% after visible-light illumination for 1 h and 20 min, while N/TiO2, Nd/TiO2 and TiO2 only showed a 67%, 43% and 31% decolorization efficiency, respectively. The enhanced photocatalytic activity of the Nd-N/TiO2 photocatalyst was due to a decrease in the electron/hole’s recombination and the increased absorption of TiO2 in the visible range. The reusability results showed that the average photocatalytic activity decrease for all the samples was only about 16% after five consecutive cycles, indicating a good stability of the prepared nanomaterials. Moreover, the radical scavenging activity of the prepared nanomaterials was evaluated using the DPPH method. The novel Nd-N/TiO2 exhibited a higher antioxidant activity compared to all the other samples.
Cytotoxic N-Methylpretrichodermamide B Reveals Anticancer Activity and Inhibits P-Glycoprotein in Drug-Resistant Prostate Cancer Cells
Authors: Dyshlovoy Sergey A. , Busenbender Tobias , Hauschild Jessica , Girich Elena V. , Kriegs Malte , Hoffer Konstantin , Graefen Markus , Yurchenko Anton N. , Bokemeyer Carsten , von Amsberg Gunhild
Published: September 2022

N-methylpretrichodermamide B (NB) is a biologically active epidithiodiketopiperazine isolated from several strains of the algae-derived fungus Penicillium sp. Recently, we reported the first data on its activity in human cancer cells lines in vitro. Here, we investigated the activity, selectivity, and mechanism of action of NB in human prostate cancer cell lines, including drug-resistant subtypes. NB did not reveal cross-resistance to docetaxel in the PC3-DR cell line model and was highly active in hormone-independent 22Rv1 cells. NB-induced cell death was stipulated by externalization of phosphatidylserine and activation of caspase-3. Moreover, inhibition of caspase activity by z-VAD(OMe)-fmk did not affect NB cytotoxicity, suggesting a caspase-independent cell death induced by NB. The compound has a moderate p-glycoprotein (p-gp) substrate-like affinity and can simultaneously inhibit p-gp at nanomolar concentrations. Therefore, NB resensitized p-gp-overexpressing PC3-DR cells to docetaxel. A kinome profiling of the NB-treated cells revealed, among other things, an induction of mitogen-activated protein kinases JNK1/2 and p38. Further functional analysis confirmed an activation of both kinases and indicated a prosurvival role of this biological event in the cellular response to the treatment. Overall, NB holds promising anticancer potential and further structure–activity relationship studies and structural optimization are needed in order to improve its biological properties.
Effect of β-Blocker Therapy on the Level of Soluble ST2 Protein in Pediatric Dilated Cardiomyopathy
Authors: Jiao Meng , Wang Xiaofang , Liang Yongmei , Yang Yifei , Gu Yan , Wang Zhiyuan , Lv Zhenyu , Jin Mei
Published: September 2022

Background and Objectives: A prognosis for kids with pediatric dilated cardiomyopathy (PDCM) is urgently needed to identify high-risk patients. This study aimed to determine the association of levels and soluble suppression of tumorigenicity 2 (sST2) and medical therapy of β-blocker inhibitors with the risk of adverse events in PDCM. Materials and Methods: A total of 124 patients with PDCM were enrolled after admission from 2 centers in China and followed up for adverse events (death, cardiac transplantation, and heart-failure-related rehospitalization). Based on a median sST2 level and the usage of β-blocker inhibitors, patients were divided into four groups. The Cox proportional hazard model was used to assess the risk of incident adverse events. Results: The median level of sST2 was 23.77 ng/mL, and 53 (42.7%) patients received β-blocker treatment. Over a median follow-up of 678 days, 37 (29.8%) adverse events occurred. Compared with patients with sST2 < median and without β-blocker, patients with sST2 ≥ median and without β-blocker (HR: 7.01; 95% CI: 1.21–40.45), followed by those with sST2 ≥ median and use of β-blocker had the highest risk of adverse events (hazard ratio (HR): 5.51; 95% confidence interval (CI): 1.17–25.84). However, a significant association was not observed in patients with sST2 < median and use of β-blocker. These associations were consistent across different subgroups. Conclusions: A higher level of sST2 was associated with a higher risk of adverse events in patients with PDCM, and β-blocker treatment for children with high levels of sST2 can effectively avoid adverse events.
External Apical Root Resorption in Orthodontic Patients Who Practice Combat Sports: A Case-Control Observational Pilot Study
Authors: Acevedo-Mascarúa Alfonso Enrique , Torres-Rosas Rafael , Pérez-Cervera Yobana , Pérez-Cruz Daniel , Ku-Valenzuela Lizbeth Zulema , Gijón-Soriano Ana Lilia , Argueta-Figueroa Liliana
Published: September 2022

Orthodontic treatment could lead to undesirable effects such as external apical root resorption (EARR). Moreover, trauma to both the face and teeth can predispose to EARR. On the other hand, the practice of combat sports results in increased maxillofacial injuries. Consequently, our objective was to determine if there is a statistically significant difference in the EARR of the patients undergoing fixed orthodontic treatment who practice combat sports and controls. Our null hypothesis was that there is no difference in the EARR between patients undergoing orthodontic treatment who practice combat sports and the patients under the same treatment that do not practice combat sports. An observational, descriptive, and prospective case-control pilot study was designed. The exposed group consisted of patients that practice combat sports. Whereas the control group was conformed of patients that do not practice combat sports without a previous history of facial trauma and without face trauma during the orthodontic treatment. EARR of the maxillary and mandibular anterior teeth was measured using cone-beam computed tomography (CBCT). The CBCT scans were obtained from all patients prior to the beginning of the orthodontic treatment and 1 year later. At the end of the follow-up for the maxillary right central and lateral incisors of the exposed group, the EARR was significantly higher than the homologous teeth of the control group (p < 0.05). As a consequence, the patients treated orthodontically who practice combat sports could be more susceptible to EARR.
Crohn’s Disease and Jejunal Artery Aneurysms: A Report of the First Case and a Review of the Literature
Authors: Vincenzi Paolo , Gaudenzi Diletta , Mulazzani Luca , Rebonato Alberto , Patriti Alberto
Published: September 2022

Background and Objectives: Jejunal artery (JA) and ileal artery (IA) aneurysms constitute less than 3% of all visceral artery aneurysms (VAAs), carrying a risk of rupture as high as 30%, and a mortality of 20%. Though many etiologies have been reported in the literature, no mention exists on a causal association between these aneurysms and inflammatory bowel diseases (IBD). We present the first case of a JA aneurysm related to Crohn’s Disease (CD) together with a review of the literature. Materials and Methods: A 74-year-old male presenting with CD intestinal relapse and an incidental finding at the computed tomography enterography (CTE) of a 53 × 47 × 25mm apparently intact JA pseudoaneurysm, arising from the first and second jejunal branches, underwent coil embolization followed by small bowel resection, with an uneventful outcome. We also included the review of literature on JA and IA aneurysms, analyzing all reports published in PubMed and Scopus from 1943 to July 2022. Results: 60 manuscripts with 103 cases of JA and IA aneurysms in 100 patients were identified. Among cases with available data, 34 (33.0%) presented acutely with rupture, 45 (43.7%) were described as non-ruptured. 83 (80.6%), and 14 (13.6%) were JA and IA aneurysms, respectively, having a median size of 15 (range:3.5–52) mm. Atherosclerosis (16.5%), infections (10.7%), and vasculitides/connective tissue disorders (9.7%) represented the main causes mentioned. Mean age was 53.6 (±19.2) years, male patients being 59.4%. One third of patients (32.4%) were asymptomatic. Overall, treatment was indicated in 63% of patients, with surgery and endovascular procedures performed in 61.9% and 38.1% cases, respectively. The technical success rate of endovascular treatment (EVT) was 95.8%. The mortality rate was 11.8%, being higher (21.2%) in the rupture group. Conclusions: The prompt treatment accomplished in our case granted a successful outcome. JA and IA aneurysms should be included among local complications of IBD. Considering their high potential for rupture, regardless of size, a low threshold for endovascular or surgical treatment should be applied.
Misfit of Implant-Supported Zirconia (Y-TZP) CAD-CAM Framework Compared to Non-Zirconia Frameworks: A Systematic Review
Authors: Alsayed Hussain
Published: September 2022

Objective: The aim of the study was to systematically review the overall outcomes of studies comparing the misfit of yttria-stabilized zirconia (Y-TZP) CAD-CAM implant-supported frameworks with frameworks fabricated with other materials and techniques. Methods: An electronic literature search of English literature was performed using Google Scholar, Scopus, Web of Science, MEDLINE (OVID), EMBASE, and PubMed, using predetermined inclusion criteria. Specific terms were utilized in conducting a search from the inception of the respective database up to May 2022. After the search strategy was applied, the data were extracted and the results were analyzed. The focused question was: Is the misfit of the implant-supported zirconia CAD-CAM framework lower than that of non-Y-TZP implant-supported fixed restorations? Results: Eleven articles were included for qualitative assessment and critical appraisal in this review. In the included studies, Y-TZP CAD-CAM implant-supported frameworks were compared to Titanium (Ti), Ni-Cr, Co-Cr, PEEK and high-density polymer, and cast and CAD-CAM frameworks. The studies used scanning electron microscopy, one-screw tests, digital or optical microscopy, 3D virtual assessment, and replica techniques for analyzing the misfit of frameworks. Six studies showed comparable misfits among the Y-TZP CAD-CAM frameworks and the controls. Three studies showed higher misfits for the Y-TZP CAD-CAM frameworks, whereas two studies reported lower misfits for Y-TZP CAD-CAM implant frameworks compared to controls. Conclusion: Y-TZP CAD-CAM implant-supported frameworks have comparable misfits to other implant-supported frameworks. However, due to heterogeneity in the methodologies of the included studies, the overall numerical misfit of the frameworks assessed in the reviewed studies is debatable
The “www” of Xenopus laevis Oocytes: The Why, When, What of Xenopus laevis Oocytes in Membrane Transporters Research
Authors: Bhatt Manan , Di Iacovo Angela , Romanazzi Tiziana , Roseti Cristina , Cinquetti Raffaella , Bossi Elena
Published: September 2022

After 50 years, the heterologous expression of proteins in Xenopus laevis oocytes is still essential in many research fields. New approaches and revised protocols, but also classical methods, such as the two-electrode voltage clamp, are applied in studying membrane transporters. New and old methods for investigating the activity and the expression of Solute Carriers (SLC) are reviewed, and the kinds of experiment that are still useful to perform with this kind of cell are reported. Xenopus laevis oocytes at the full-grown stage have a highly efficient biosynthetic apparatus that correctly targets functional proteins at the defined compartment. This small protein factory can produce, fold, and localize almost any kind of wild-type or recombinant protein; some tricks are required to obtain high expression and to verify the functionality. The methodologies examined here are mainly related to research in the field of membrane transporters. This work is certainly not exhaustive; it has been carried out to be helpful to researchers who want to quickly find suggestions and detailed indications when investigating the functionality and expression of the different members of the solute carrier families.
An Investigation of the Constructional Design Components Affecting the Mechanical Response and Cellular Activity of Electrospun Vascular Grafts
Authors: Ozdemir Suzan , Yalcin-Enis Ipek , Yalcinkaya Baturalp , Yalcinkaya Fatma
Published: September 2022

Cardiovascular disease is anticipated to remain the leading cause of death globally. Due to the current problems connected with using autologous arteries for bypass surgery, researchers are developing tissue-engineered vascular grafts (TEVGs). The major goal of vascular tissue engineering is to construct prostheses that closely resemble native blood vessels in terms of morphological, mechanical, and biological features so that these scaffolds can satisfy the functional requirements of the native tissue. In this setting, morphology and cellular investigation are usually prioritized, while mechanical qualities are generally addressed superficially. However, producing grafts with good mechanical properties similar to native vessels is crucial for enhancing the clinical performance of vascular grafts, exposing physiological forces, and preventing graft failure caused by intimal hyperplasia, thrombosis, aneurysm, blood leakage, and occlusion. The scaffold’s design and composition play a significant role in determining its mechanical characteristics, including suturability, compliance, tensile strength, burst pressure, and blood permeability. Electrospun prostheses offer various models that can be customized to resemble the extracellular matrix. This review aims to provide a comprehensive and comparative review of recent studies on the mechanical properties of fibrous vascular grafts, emphasizing the influence of structural parameters on mechanical behavior. Additionally, this review provides an overview of permeability and cell growth in electrospun membranes for vascular grafts. This work intends to shed light on the design parameters required to maintain the mechanical stability of vascular grafts placed in the body to produce a temporary backbone and to be biodegraded when necessary, allowing an autologous vessel to take its place.
Microtransplantation of Postmortem Native Synaptic mGluRs Receptors into Xenopus Oocytes for Their Functional Analysis
Authors: Miller Brice , Moreno Naomi , Gutierrez Berenice A. , Limon Agenor
Published: September 2022

Metabotropic glutamate receptors (mGluRs) are membrane receptors that play a central role in the modulation of synaptic transmission and neuronal excitability and whose dysregulation is implicated in diverse neurological disorders. Most current understanding about the electrophysiological properties of such receptors has been determined using recombinant proteins. However, recombinant receptors do not necessarily recapitulate the properties of native receptors due to the lack of obligated accessory proteins, some of which are differentially expressed as function of developmental stage and brain region. To overcome this limitation, we sought to microtransplant entire synaptosome membranes from frozen rat cortex into Xenopus oocytes, and directly analyze the responses elicited by native mGluRs. We recorded ion currents elicited by 1 mM glutamate using two electrodes voltage clamp. Glutamate produced a fast ionotropic response (6 ± 0.3 nA) in all microtransplanted oocytes (n = 218 oocytes) and a delayed oscillatory response (52 ± 7 nA) in 73% of them. The participation of Group 1 mGluRs was confirmed by the presence of metabotropic oscillations during the administration of (±)-1-Aminocyclopentane-trans-1,3-dicarboxylic acid (ACPD; Group 1 mGluR agonist), and the absence of oscillations during co-administration of N-(1-adamantyl)quinoxaline-2-carboxamide (NPS 2390; Group 1 mGluR antagonist). Since both mGluR1 and mGluR5 belong to Group 1 mGluRs, further investigation revealed that mGluR1 antagonism with LY 456236 has little effect on metabotropic oscillations, while mGluR5 antagonism with 100 µM AZD 9272 has significant reduction of metabotropic currents elicited by ACPD and glutamate. We confirmed the expression of mGluR1 and mGluR5 in native synaptosomes by immunoblots, both of which are enhanced when compared to their counterpart proteins in rat cortex tissue lysates. Finally, these results demonstrate the merit of using microtransplantation of native synaptosomes for the study of mGluRs and the contribution of mGluR5 to the metabotropic glutamate signaling, providing a better tool for the understanding of the role of these receptors in neurological disorders.
Three New Compounds, Licopyranol A–C, Together with Eighteen Known Compounds Isolated from Glycyrrhiza glabra L. and Their Antitumor Activities
Authors: Wang Shanshan , Alafifi Jameel Hizam , Chen Qin , Shen Xue , Bi Chunmei , Wu Yangyang , Jiang Yihan , Liu Yanan , Li Yimeng , He Dian , Yang Zhigang
Published: September 2022

Glycyrrhiza glabra L., known as licorice, is one of the most famous herbs in the world. In this study, we investigated the phytochemical and antitumor activities of G. glabra, especially its anti-colorectal cancer activities. G. glabra was extracted with 70% methanol, and the ethyl acetate layer was separated by silica gel, ODS, LH-20 column chromatography, and semi-preparative HPLC to obtain the compounds. The structures were determined by NMR and MS methods. Three new compounds named licopyranol A–C (1–3), and eighteen known compounds (4–21) were isolated. Compounds with an isoprenyl group or dimethylpyran ring showed better antitumor activities. Licopyranol A (1) and glycyrol (5) both inhibited the proliferation, reduced clone formation and promoted apoptosis of RKO cells. The Western blotting assays showed that glycyrol significantly reduced the expression of E-cadherin, β-catenin, c-Myc, and GSK-3β proteins in RKO cells, suggesting that glycyrol may inhibit the growth of colorectal cancer RKO cells via the Wnt/β-catenin signaling pathway.
N-3 Fatty Acid Supplementation Impacts Protein Metabolism Faster Than it Lowers Proinflammatory Cytokines in Advanced Breast Cancer Patients: Natural 15N/14N Variations during a Clinical Trial
Authors: Mantha Olivier L. , Hankard Régis , Tea Illa , Schiphorst Anne-Marie , Dumas Jean-François , Berger Virginie , Goupille Caroline , Bougnoux Philippe , De Luca Arnaud
Published: September 2022

While clinical evidence remains limited, an extensive amount of research suggests a beneficial role of n-3 polyunsaturated fatty acid supplementation in cancer treatment. One potential benefit is an improvement of protein homeostasis, but how protein metabolism depends on proinflammatory cytokines in this context remains unclear. Here, using the natural abundance of the stable isotopes of nitrogen as a marker of changes in protein metabolism during a randomized, double-blind, controlled clinical trial, we show that protein homeostasis is affected way faster than proinflammatory cytokines in metastatic breast cancer patients supplemented with n-3 polyunsaturated fatty acids. We provide some evidence that this response is unrelated to major changes in whole-body substrate oxidation. In addition, we demonstrate that more fatty acids were impacted by metabolic regulations than by differences in their intake levels during the supplementation. This study documents that the percentage of patients that complied with the supplementation decreased with time, making compliance assessment crucial for the kinetic analysis of the metabolic and inflammatory responses. Our results highlight the time-dependent nature of metabolic and inflammatory changes during long-chain n-3 fatty acid supplementation.
Thermal Conductivity Measurement of Flexible Composite Phase-Change Materials Based on the Steady-State Method
Authors: Feng Ze , Xiao Xin
Published: September 2022

Phase-change materials (PCMs) are widely used in energy storage and thermal management due to the large latent heat in the phase-change process. As one of the most significantly thermophysical properties of PCMs, the thermal conductivity has been extensively studied. Great attention has been paid to improving the thermal conductivities of PCMs; however, the studies on the thermal conductivities of flexible PCMs are relatively inadequate. In this study, polyethylene glycol 1500 (PEG1500) was used as the base PCM, and expanded graphite (EG) and styrene–butadiene–styrene (SBS) were added to improve the thermal conductivity and flexibility of pure PCMs, respectively. A steady-state experimental test rig was built and verified with the measurement of the thermal conductivity of stainless steel and deionized water, and then the thermal conductivities of PCMs at different phases and qualitative temperatures were measured extensively. Compared to the PEG1500 with 5 wt.% EG, the addition of SBS sharply reduces the thermal conductivity, which is only 0.362 W/(m·K) at 12.5 °C when the addition ratio is 50%. This is approximately a 69% reduction compared with the composite PCMs without SBS. Furthermore, the theoretical thermal conductivities of the composite PCMs were calculated with six theoretical models of multiphase systems. The majority of the models provide a good prediction of thermal conductivities of composite PCM with high SBS concentration, while the average deviation of Agari-Uno model is only 20.5% with different SBS concentration and relatively agrees well with the experimental results.
Fabrication of Multilayer Molds by Dry Film Photoresist
Authors: Koucherian Narek E. , Yan Shijun , Hui Elliot E.
Published: September 2022

Dry film photoresists are widely employed to fabricate high-aspect-ratio microstructures, such as molds for microfluidic devices. Unlike liquid resists, such as SU-8, dry films do not require a cleanroom facility, and it is straightforward to prepare uniform and reproducible films as thick as 500 µm. Multilayer patterning, however, can be problematic with dry film resists even though it is critical for a number of microfluidic devices. Layer-to-layer mask alignment typically requires the first layer to be fully developed, making the pattern visible, before applying and patterning the second layer. While a liquid resist can flow over the topography of previous layers, this is not the case with dry film lamination. We found that post-exposure baking of dry film photoresists can preserve a flat topography while revealing an image of the patterned features that is suitable for alignment to the next layer. We demonstrate the use of this technique with two different types of dry film resist to fabricate master molds for a hydrophoresis size-sorting device and a cell chemotaxis device.
Novel Endovascular Interventional Surgical Robotic System Based on Biomimetic Manipulation
Authors: Song Chao , Xia Shibo , Zhang Hao , Zhang Lei , Li Xiaoye , Wang Kundong , Lu Qingsheng
Published: September 2022

Endovascular therapy has emerged as a crucial therapeutic method for treating vascular diseases. Endovascular surgical robots have been used to enhance endovascular therapy. However, to date, there are no universal endovascular surgical robots that support molds of different types of devices for treating vascular diseases. We developed a novel endovascular surgical robotic system that can independently navigate the intravascular region, advance and retract devices, and deploy stents. This robot has four features: (1) The bionic design of the robot can fully simulate the entire grasping process; (2) the V-shaped relay gripper waived the need to redesign special guidewires and catheters for continuous rotation; (3) the handles designed based on the feedback mechanism can simulate push resistance and reduce iatrogenic damage; and (4) the detachable design of the grippers can reduce cross-infection risk and medical costs. We verified its performance by demonstrating six different types of endovascular surgeries. Early evaluation of the novel endovascular robotic system demonstrated its practicability and safety in endovascular surgeries.