bluuebunny/crossref_metadata_2025 huggingface dataset:
Increasing the Lithium Ion Mobility in Poly(Phosphazene)-Based Solid Polymer Electrolytes through Tailored Cation Doping
Authors: Ingber Tjark T. K. , Liebenau Dominik , Biedermann Myra , Kolek Martin , Diddens Diddo , Wiemhöfer Hans-Dieter , Heuer Andreas , Winter Martin , Bieker Peter
Published: July 2021

Solid polymer electrolytes (SPEs) are promising candidates for usage in rechargeable lithium metal batteries (LMBs) as they possess high mechanical, thermal, and chemical stability. However, the poor ionic conductivity of SPEs in comparison to liquid electrolytes hampers the commercialization of SPE-based LMBs. In the case of poly[bis(methoxy-ethoxy-ethoxy-)phosphazene] (MEEP), one explanation for the low ionic conductivity is the trapping of lithium cations in backbone coordination sites, hindering lithium ion movement through the electrolyte membrane. Herein, modelling the ion coordination in MEEP using DFT calculations reveals that, compared to lithium, heavier alkali cations are more likely to be complexed at the backbone coordination sites. With other alkali cations masking these coordination sites, enhanced lithium ion mobility through the SPE is expected. Experimental data proves these expectations: doping MEEP-based LiBOB-containing SPE membranes with small amounts of in-house synthesized potassium bis(oxalato)borate (KBOB) increases the lithium ion transference number from 0.08 to 0.18. Also, the partial lithium ion conductivity of the salt-in-MEEP electrolyte is boosted to outstanding 0.08 mS cm−1, far exceeding state-of-the-art literature values for this material. A cross-check using SPEs based on the structurally similar poly(ethylene oxide) (PEO) validates the proposed cation displacement model. The obtained insights may aid the development of highly effective poly(phosphazene)-based SPEs.
Alkaline Electrochemical Reduction of a Magnesium Ferrospinel into Metallic Iron for the Valorisation of Magnetite-Based Metallurgical Waste
Authors: Lopes Daniela V. , Lisenkov Aleksey D. , Sergiienko Sergii A. , Constantinescu Gabriel , Sarabando Artur , Quina Margarida J. , Frade Jorge R. , Kovalevsky Andrei V.
Published: July 2021

The electrochemical reduction of iron oxides in alkaline media arises as a novel approach for ironmaking and iron-rich waste valorisation. Strong advantages and attractive aspects of alkaline electroreduction include lower electric energy consumption, absence of CO2 emissions, and non-polluting valuable by-products such as H2 and O2. Another potential advantage originates from the compatibility of this concept with intermittent renewable energies. However, to bring this technology to a competitive level, especially compared to the traditional steelmaking, innovative approaches and developments in materials processing and their appropriate integration into the electrolysis process are required. This research work explores the prospects for electrochemical reduction of a magnesium-containing ferrospinel, as a potential component in iron-containing wastes. The experimental approach considers bulk cathode- and suspension-based electrolysis concepts, which allow reaching 55% and 20% Faradaic efficiencies of the reduction to metallic iron, respectively. The effects imposed by the magnesium presence on the electroreduction kinetics, phase composition and morphology of the electroreduction products are evaluated and discussed. The obtained results open new perspectives for the recovery of metallurgical residues with low magnesium impurities content.
An Autocontouring Method for the Kidneys Using an Adaptive Weighted Multikernel Support Vector Machines
Authors: Gu Yi , Li Bo
Published: July 2021

In radiotherapy, the location of the target area is very important. If the target area is small, the treatment is not complete, so the location of the target area is generally larger than the actual cancerous site. However, the damage of radiotherapy to normal cells is the same. In order to reduce the damage to the body as much as possible, we need to complete the most suitable target area. This paper uses an adaptive weighted multikernel support vector machine, which solves the parameter problem in the traditional multikernel support vector machine. The new AW-SVM can adjust the kernel weights adaptively. We completed our experiment on the abdominal MR dataset, using DSI as an evaluation indicator, and the experimental results showed its excellent classification performance. The minimum value of DSI in all results is 0.9654 (more than 0.7 is acceptable).
Integrative Bioinformatics Study of Tangeretin Potential Targets for Preventing Metastatic Breast Cancer
Authors: Hermawan Adam , Putri Herwandhani , Hanif Naufa , Ikawati Muthi
Published: July 2021

Agents that target metastasis are important to improve treatment efficacy in patients with breast cancer. Tangeretin, a citrus flavonoid, exhibits antimetastatic effects on breast cancer cells, but its molecular mechanism remains unclear. Tangeretin targets were retrieved from PubChem, whereas metastatic breast cancer regulatory genes were downloaded from PubMed. In total, 58 genes were identified as potential therapeutic target genes of tangeretin (PTs). GO and KEGG pathway enrichment analyses of PTs were performed using WebGestalt (WEB-based Gene SeT AnaLysis Toolkit). The PPI network was analyzed using STRING-DB v11.0 and visualized by Cytoscape software. Hub genes were selected on the basis of the highest degree score as calculated by the CytoHubba plugin. Genetic alterations of the PTs were analyzed using cBioPortal. The prognostic values of the PTs were evaluated with the Kaplan–Meier plot. The expression of PTs across breast cancer samples was confirmed using GEPIA. The reliability of the PTs in metastatic breast cancer cells was validated using ONCOMINE. Molecular docking was performed to foresee the binding sites of tangeretin with PIK3Cα, MMP9, PTGS2, COX-2, and IKK. GO analysis showed that PTs participate in the biological process of stimulus response, are the cellular components of the nucleus and the membrane, and play molecular roles in enzyme regulation. KEGG pathway enrichment analysis revealed that PTs regulate the PI3K/Akt pathway. Genetic alterations for each target gene were MTOR (3%), NOTCH1 (4%), TP53 (42%), MMP9 (4%), NFKB1 (3%), PIK3CA (32%), PTGS2 (15%), and RELA (5%). The Kaplan–Meier plot showed that patients with low mRNA expression levels of MTOR, TP53, MMP9, NFKB1, PTGS2, and RELA and high expression of PIK3CA had a significantly better prognosis than their counterparts. Further validation of gene expression by using GEPIA revealed that the mRNA expression of MMP9 was significantly higher in breast cancer tissues than in normal tissues, whereas the mRNA expression of PTGS2 showed the opposite. Analysis with ONCOMINE demonstrated that the mRNA expression levels of MMP9 and NFKB1 were significantly higher in metastatic breast cancer cells than in normal tissues. The results of molecular docking analyses revealed the advantage of tangeretin as an inhibitor of PIK3CA, MMP9, PTGS2, and IKK. Tangeretin inhibits metastasis in breast cancer cells by targeting TP53, PTGS2, MMP9, and PIK3CA and regulating the PI3K/Akt signaling pathway. Further investigation is needed to validate the results of this study.
Homogeneous Wave Load Effects on the Connections of Main Parts of Side-Anchored Straight Floating Bridge
Authors: Rajabi Meysam , Ghassemi Hassan , Ghafari Hamidreza
Published: July 2021

In this paper, a numerical study is presented to investigate wave force on the connections of main parts of a side-anchored straight floating bridge concept for the Bjørnafjorden fjord crossing. The floating bridge is supported by 18 pontoons, and three groups of mooring lines are employed to restrain the bridge against horizontal loads and increase its transverse stiffness. The created wave forces at the connections of pontoon-column and column-girder of the floating bridge considering the effects of short-crested and long-crested waves, varying wave direction, hydrodynamic interaction between pontoons, and mooring system are analyzed. It is found that short-crested and long-crested waves depending on their direction decrease or increase the wave forces on the joints. Considering that the effect of hydrodynamic interaction between pontoons can increase or reduce the wave forces and moments created in the joints, which means the neglect of the hydrodynamic interaction effects between the pontoons to simplify the modeling of this type of floating bridge, may be unacceptable. Moreover, the results showed that the bridge mooring system does not merely reduce the wave forces and moments at joints along the bridge.
[Retracted] Neural Network Optimal Routing Algorithm Based on Genetic Ant Colony in IPv6 Environment
Authors: Ni Weichuan , Xu Zhiming , Zou Jiajun , Wan Zhiping , Zhao Xiaolei
Published: July 2021

The traditional IPv6 routing algorithm has problems such as network congestion, excessive energy consumption of nodes, and shortening the life cycle of the network. In response to this phenomenon, we proposed a routing optimization algorithm based on genetic ant colony in IPv6 environment. The algorithm analyzes and studies the genetic algorithm and the ant colony algorithm systematically. We use neural network to build the initial model and combine the constraints of QoS routing. We effectively integrate the genetic algorithm and ant colony algorithm that maximize their respective advantages and apply them to the IPv6 network. At the same time, in order to avoid the accumulation of a lot of pheromones by the ant colony algorithm in the later stage of the network, we have introduced an anticongestion reward and punishment mechanism. By comparing the search path with the optimal path, rewards and punishments are based on whether the network path is smooth or not. Finally, it is judged whether the result meets the condition, and the optimal solution obtained is passed to the BP neural network for training; otherwise, iterative iterations are required until the optimal solution is satisfied. The experimental results show that the algorithm can effectively adapt to the IPv6 routing requirements and can effectively solve the user’s needs for network service quality, network performance, and other aspects.
The Effect and Mechanism of lncRNA NR2F1-As1/miR-493-5p/MAP3K2 Axis in the Progression of Gastric Cancer
Authors: Liao Xiaobin , Wen Linbao , Luo Liqiong
Published: July 2021

Background. LncRNA NR2F1-AS1 has been identified as an oncogene in some human tumors, such as breast cancer, nonsmall cell lung cancer, and esophageal squamous cell carcinoma. Nonetheless, whether NR2F1-AS1 is involved in the progression of gastric cancer (GC) remains unknown. Methods. The expression patterns of NR2F1-AS1, MAP3K2, and miR-493-5p in GC tissues and cells were detected by RT-qPCR. The protein expression of MAP3K2 was assessed by the Western blotting assay. The MTT assay and flow cytometry were performed to measure cell proliferation and cell apoptosis in GC cells. The transwell assay was adopted to assess cell migration in GC cells. The relationship between NR2F1-AS1, MAP3K2, and miR-493-5p was verified by a dual-luciferase reporter assay. Results. The increased NR2F1-AS1 and MAP3K2 expressions were discovered in GC tissues and cells compared with control groups. Knockdown of NR2F1-AS1 and MAP3K2 dramatically suppressed cell proliferation and migration, while it enhanced cell apoptosis in GC cells. In addition, NR2F1-AS1 was found to be a sponge of miR-493-5p, and MAP3K2 was a downstream gene of miR-493-5p. Moreover, the expression of MAP3K2 was notably reduced by miR-493-5p, and NR2F1-AS1 counteracted the inhibition of miR-493-5p. Conclusion. Thus, NR2F1-AS1 was verified to regulate GC cell progression by sponging miR-493-5p to upregulate MAP3K2 expression.
Chest Pain from Pneumopericardium with Gastropericardial Fistula
Authors: Rathur Abdullah , Al-Mohamad Hussein , Steinhoff Jeffrey , Walsh Ronald
Published: July 2021

Introduction. Gastropericardial fistula, a connection between the upper gastrointestinal tract and pericardium, is a rare clinical finding most commonly associated with postsurgical complications, as well as direct tissue invasion from gastric cancer. Case Report. We report a case of a 58-year-old Caucasian woman with metastatic colon cancer treated with FOLFOX, a combination chemotherapy regimen, and bevacizumab who presented with chest pain. She was ruled out for acute coronary syndrome, aortic dissection, or pulmonary embolism. A computed tomography (CT) scan of her chest showed pneumopericardium. A barium swallow ruled out esophageal ulceration, and esophagogastroduodenoscopy (EGD) showed a large penetrating gastric ulcer with no evidence of gastric dysplasia or malignancy or evidence of Helicobacter pylori (H. pylori). The patient underwent median sternotomy with gastric ulcer resection and repair, as well as pericardial washout and pericardial chest tube placement. After an uncomplicated course, she was safely discharged home. Conclusion. Given that gastrointestinal ulceration and perforation are known phenomena in patients taking vascular endothelial growth factor (VEGF) inhibitors, surveillance endoscopy may be beneficial to discover them before they result in potentially fatal complications such as gastropericardial fistulas.
Arrested Puberty in an Adolescent Male with Anorexia Nervosa Successfully Resumed with Multidisciplinary Care
Authors: Simão Raimundo Diana , Figueiredo Carolina , Raposo Ana , Dias Pereira Bernardo
Published: July 2021

The normal development of puberty depends on the specific pulsatility of gonadorelin, which is finely regulated by genetic and environmental factors. In the published literature, eating disorders figure as a cause of pubertal delay/arrest in females but are rarely considered in males with disordered puberty. A 16.7-year-old male was referred to the Department of Pediatrics with arrested puberty due to severe malnutrition in the context of food restriction. Past medical history was relevant for asthma. Generalized cachexia, facial lanugo hair, cutaneous xerosis, and Russell’s sign were noted; he had a height of 155.5 cm (−2.5 SD; target height: 168 cm, −1.1 SD) and a BMI of 12.4 kg/m2 (−6.8 SD); left and right testicular volumes were 8 mL and 10 mL, respectively. He had a twin brother who had normal auxological/pubertal development (height: 167 cm, −1.05 SD; testicular volumes: 20 mL). Anorexia nervosa was diagnosed, and he was enrolled in a personalized treatment and surveillance program. “Nonthyroid illness” resembling secondary hypothyroidism was noted, as was low bone mineral density. Clinical and biochemical follow-up showed significant improvements in BMI (16.2 kg/m2, −2.55 SD), completion of puberty (testicular volumes: 25 mL), and reversion of main neuroendocrine abnormalities. Herein, we present an adolescent male with arrested puberty in the context of anorexia nervosa. The recognition of this rare condition in males allows a personalized approach to disordered puberty, with resumption of normal function of the hypothalamic-pituitary-gonadal axis and achievement of pubertal milestones.
Structural Parameters Optimization of Corona Ring of Tethered Balloon-Type VLF Antenna
Authors: Wang Ao , Li Xianqiang , Zhang Huajun , Tian Ji , Zhou Wenchuang
Published: July 2021

The antenna end of the tethered balloon-type high-power VLF communication system will be exposed to an extremely strong alternating electric field environment when it is in operation. Due to dielectric loss, an abnormal temperature rise may occur at the antenna end, which may lead to an antenna fracture in serious cases. It is an effective measure to install a corona ring at the end of the antenna to prevent such accidents. In this paper, the structural parameters of the corona ring, including ring radius, tube radius, and ring depth, are optimized based on intelligent optimization algorithm to significantly improve the electric field distribution and restrain the temperature rise to the maximum extent. The effectiveness of the optimization results is verified by simulation.
Leveraging the Power of Deep Learning Technique for Creating an Intelligent, Context‐Aware, and Adaptive M‐Learning Model
Authors: Adnan Muhammad , AlSaeed Duaa H. , Al-Baity Heyam H. , Rehman Abdur
Published: July 2021

Machine learning (ML) and deep learning (DL) algorithms work well where future estimations and predictions are required. Particularly, in educational institutions, ML and DL algorithms can help instructors in predicting the learning performance of learners. Furthermore, the prediction of the learning performance of learners can assist instructors and intelligent learning systems (ILSs) in taking preemptive measures (i.e., early engagement or early intervention measures) so that the learning performance of weak learners could be increased thus reducing learners’ failures and dropout rates. In this study, we propose an intelligent learning system (ILS) powered by the mobile learning (M‐learning) model that predicts learners’ performance and classify them into various performance groups. Subsequently, adaptive feedback and support are provided to those learners who struggle in their studies. Four M‐learning models were created for different learners considering their learning features (study behavior) and their weight values. The M‐learning model was based on the artificial neural network (ANN) algorithm with the aim to predict learners’ performance and classify them into five performance groups, whereas the random forest (RF) algorithm was used to determine each feature’s importance in the creation of the M‐learning model. In the last stage of this study, we performed an early intervention/engagement experiment on those learners who showed weak performance in their study. End‐user computing satisfaction (EUCS) model questionnaire was adopted to measure the attitude of learners towards using an ILS. As compared to traditional machine learning algorithms, ANN achieved the highest prediction accuracy for all four learning models, i.e., model 1 = 90.77%, model 2 = 87.69%, model 3 = 83.85%, and model 4 = 80.00%. Moreover, the five most important features that significantly affect the students’ final performance were MP3 = 0.34, MP1 = 0.26, MP2 = 0.24, NTAQ = 0.05, and AST = 0.018.
Practices and Barriers towards Physical Assessment among Nurses Working in Intensive Care Units: Multicenter Cross‐Sectional Study
Authors: Liyew Bikis , Tilahun Ambaye Dejen , Kassew Tilahun
Published: July 2021

Background. In the intensive care units, patients need special consideration and monitor frequently with appropriate physical assessment skills. Nurses working in the intensive care units play a fundamental role in detecting patients at risk of deterioration through ongoing assessment and action in response to changing health status. Most of the nursing activities were poorly assessed in low‐income countries including Ethiopia. Therefore, this study was aimed to assess the nurses’ practice and barriers to physical assessment among critically ill patients in Northwest Ethiopia. Methods. An institution‐based multicenter cross‐sectional study was conducted at Amhara regional state referral hospitals from March to September 2019. A total of 299 nurses working in the intensive care units were recruited through the convenience sampling method. A 30‐item physical assessment practice and 36‐item barriers to nurses’ use of the physical assessment scale inventory were used. The linear regression analysis model was fitted, and the adjusted unstandardized beta (β) coefficient with a 95% confidence interval was used. A p value < 0.05 was considered statistically significant. Results. The mean score of the nurses’ practice towards physical assessment among critically ill patients was 101.26 ± 24.99. Greater perceived reliance on others and technology (β = −0.78, 95% CI (‐1.07, ‐0.48)), ward culture (β = −0.48, 95% CI (‐0.85, ‐0.11)), specialty area (β = −1.46, 95% CI (‐2.01, ‐0.90)), lack of nursing role model (β = −0.54, 95% CI (‐1.06, ‐0.02)), being unmarried (β = −6.10, 95% CI (1.75, 10.46)), taken training (β = 11.53, 95% CI (6.34, 16.72)), and knowledge score (β = 2.81, 95% CI (2.00, 3.63)) were the factors significantly associated with the nurses’ practice score towards physical assessment. Reliance on others and technology towards physical assessment practice was the most important barrier followed by ward culture and specialty area. Conclusion. Nurses working in the intensive care units had a good practice towards physical assessment among critically ill patients. Hence, to increase the practice towards physical assessment in intensive care settings, especially for married nurses, experienced critical care nurses, and specialist professionals, practice support training, modifying ward environment, and educational support care are recommended.
Comparison of Pluripotency, Differentiation, and Mitochondrial Metabolism Capacity in Three‐Dimensional Spheroid Formation of Dental Pulp‐Derived Mesenchymal Stem Cells
Authors: Son Young-Bum , Bharti Dinesh , Kim Saet-Byul , Jo Chan-Hee , Bok Eun-Yeong , Lee Sung-Lim , Kang Young-Hoon , Rho Gyu-Jin
Published: July 2021

Mesenchymal stem cells (MSCs) are valuable candidates in tissue engineering and stem cell‐based therapy. Traditionally, MSCs derived from various tissues have been successfully expanded in vitro using adherent culture plates commonly called as monolayer two‐dimensional (2D) cultures. Recently, many studies demonstrated that stemness and multilineage differentiation potential could be enhanced to greater extent when MSCs are cultured as suspended aggregates by means of three‐dimensional (3D) culturing techniques. However, there are limited reports on changed mitochondrial metabolism on 3D spheroid formation of MSCs. Therefore, the present study was aimed at investigating the stemness, differentiation potential, and mitochondrial metabolism capacity of 3D dental pulp‐derived MSC (DPSC) spheroids in comparison to monolayer cultured DPSCs. We isolated dental pulp‐derived MSCs (DPSCs) and successfully developed a 3D culture system which facilitated the formation of MSC spheroids. The cell aggregation was observed after 2 hours, and spheroids were formed after 24 hours and remained in shape for 72 hours. After spheroid formation, the levels of pluripotent markers increased along with enhancement in adipogenic and osteogenic potential compared to 2D cultured control cells. However, decreased proliferative capacity, cell cycle arrest, and elevated apoptosis rate were observed with the time course of the 3D culture except for the initial 24‐hour aggregation. Furthermore, oxygen consumption rates of living cells decreased with the time course of the aggregation except for the initial 24 hours. Overall, our study indicated that the short‐term 3D culture of MSCs could be a suitable alternative to culture the cells.
Influence of SGLT2 Inhibitor Treatment on Urine Antioxidant Status in Type 2 Diabetic Patients: A Pilot Study
Authors: Nabrdalik-Leśniak Diana , Nabrdalik Katarzyna , Sedlaczek Katarzyna , Główczyński Patryk , Kwiendacz Hanna , Sawczyn Tomasz , Hajzler Weronika , Drożdż Karolina , Hendel Mirela , Irlik Krzysztof , Stelmach Paweł , Adamczyk Piotr , Paradysz Andrzej , Kasperczyk Sławomir , Stompór Tomasz , Gumprecht Janusz
Published: July 2021

Sodium‐glucose cotransporter 2 inhibitors (SGLT2i) have been recognized as potent antioxidant agents. Since SGLT2i are nephroprotective drugs, we aimed to examine the urine antioxidant status in patients with type 2 diabetes mellitus (T2DM). One hundred and one subjects participated in this study, including 37 T2DM patients treated with SGLT2i, 31 T2DM patients not using SGLT2i, and 33 healthy individuals serving as a control group. Total antioxidant capacity (TAC), superoxide dismutase (SOD), manganese superoxide dismutase (MnSOD), free thiol groups (R‐SH, sulfhydryl groups), and catalase (CAT) activity, as well as glucose concentration, were assessed in the urine of all participants. Urine SOD and MnSOD activity were significantly higher among T2DM patients treated with SGLT2i than T2DM patients without SGLT2i treatment (p = 0.009 and p = 0.003, respectively) and to the healthy controls (p = 0.002 and p = 0.001, respectively). TAC was significantly lower in patients with T2DM treated with SGLT2i when compared to those not treated and healthy subjects (p = 0.036 and p = 0.019, respectively). It could be hypothesized that the mechanism by which SGLT2i provides nephroprotective effects involves improvement of the SOD antioxidant activity. However, lower TAC might impose higher OS (oxidative stress), and elevation of SOD activity might be a compensatory mechanism.
Elimination of Congo Red Dye from Industrial Wastewater Using Teucrium polium L. as a Low-Cost Local Adsorbent
Authors: Alamrani Nasser A. , AL-Aoh Hatem A.
Published: July 2021

A novel adsorbent prepared from the leaf powder of Teucrium polium L. (TPLLP) was characterized and its ability for adsorption of Cong red (CR) was inspected. Influences of CR concentration, adsorbent dosage, time of agitation, pH of solution, and temperature on the performance of this adsorption were also examined. Three models of kinetic along with three different isotherm models were applied for analyzing the empirical data of this adsorption. Additionally, the thermodynamic constants of were decided. The surface area, pore volume, pore size, and pHZPC of Zn/Cu-TPLLP were found to be 2.6436 m2.g-1, 0.013317 cm3.g-1, 527.393 Å, and 8.8, respectively. The achieved outcomes indicate the positive influence of temperature, concentration of CR in the range of 20 to 900 mg/L, adsorbent mass in the range of 0.005 to 0.02 g, time of adsorption from 0 to 120 min, and pH from 5.5 to 8.5. Models of the 2nd order with [Formula: see text] and Langmuir with [Formula: see text] were the best among the other kinetic and isotherm models applied in this research. Moreover, superior capacities of 526.32, 666.67, and 909.09 (mg.g-1) were stemmed at 27, 42, and 57°C, respectively. The outcomes of the thermodynamic evidenced that this adsorption is spontaneous and a heat absorber.
3D M‐Net: Object‐Specific 3D Segmentation Network Based on a Single Projection
Authors: Li Xuan , Wang Sukai , Niu Xiaodong , Wang Liming , Chen Ping
Published: July 2021

The internal assembly correctness of industrial products directly affects their performance and service life. Industrial products are usually protected by opaque housing, so most internal detection methods are based on X‐rays. Since the dense structural features of industrial products, it is challenging to detect the occluded parts only from projections. Limited by the data acquisition and reconstruction speeds, CT‐based detection methods do not achieve real‐time detection. To solve the above problems, we design an end‐to‐end single‐projection 3D segmentation network. For a specific product, the network adopts a single projection as input to segment product components and output 3D segmentation results. In this study, the feasibility of the network was verified against data containing several typical assembly errors. The qualitative and quantitative results reveal that the segmentation results can meet industrial assembly real‐time detection requirements and exhibit high robustness to noise and component occlusion.
Effects of Foaming and Drainage Behavior on Structure and Properties of Polyurethane/Water Glass (PU/WG) Grouting Materials for Coal Mines
Authors: Yu Xiaofeng , Liu Lizong , Wang Yuchao , Bai Guangfeng , Zhang Yu
Published: July 2021

During the grouting operation in the underground coal mine, abnormal curing behaviors such as foaming and drainage often lead to the loss of reinforcement effect of the polyurethane/water glass (PU/WG) materials on coal walls and even cause safety accidents. Herein, three kinds of PU/WG grouting materials were successfully prepared by changing the type of catalysts, which were the normal sample (C7), the foaming sample (C14), and the sample with drainage (C17) during curing. The structure, thermal stability, and compressive strength of the three samples were characterized by scanning electron microscope (SEM), energy dispersive spectroscopy (EDS), X‐ray diffraction (XRD), X‐ray photoelectron spectroscopy (XPS), thermogravimetry‐differential thermal analysis (TG‐DTA), and pressure testing machine. The results showed that the abnormal curing behavior had little effect on the thermal stability of the material, but it had a significant effect on the microstructure and compressive strength of the consolidated body. C7 exhibited a typical three‐phase distribution, in which the polysilicate microspheres encapsulated by acicular carbonate were embedded in the polymer continuum. The structure of C7 had high rigidity and hardness, and the compressive strength was up to 43 MPa. The three‐phase structure of C14 disappeared gradually with the increase of catalyst content, the hard block material and matrix are porous, and the compressive strength was only 2.7 MPa. The organic polymer of C17 existed in the form of microsphere and distributed irregularly in the continuum composed of inorganic components, and the compressive strength was 4.9 MPa. The abnormal solidification behavior such as foaming and drainage made the water glass/polyurethane material lose its basic mechanical properties, which cannot meet the needs of grouting reinforcement in coal mines. Therefore, the type of catalyst had a significant impact on the stability of the system, and it is necessary to avoid selecting catalysts that are likely to cause abnormal solidification during formulation research.
Fractal Basins of Convergence of a Seventh-Order Generalized Hénon–Heiles Potential
Authors: Zotos Euaggelos E. , Dubeibe Fredy L. , Riaño-Doncel A.
Published: July 2021

This article aims to investigate the points of equilibrium and the associated convergence basins in a seventh-order generalized Hénon–Heiles potential. Using the well-known Newton–Raphson iterator, we numerically locate the positions of the points of equilibrium, while we also obtain their linear stability. Furthermore, we demonstrate how the two variable parameters, entering the generalized Hénon–Heiles potential, affect the convergence dynamics of the system as well as the fractal degree of the basin diagrams. The fractal degree is derived by computing the (boundary) basin entropy as well as the uncertainty dimension.
Safety Evaluation of Standardized Extract of Curcuma longa (NR‐INF‐02): A 90‐Day Subchronic Oral Toxicity Study in Rats
Authors: Murugan Sasikumar , Solanki Himanshu , Purusothaman Divya , Bethapudi Bharathi , Ravalji Mital , Mundkinajeddu Deepak
Published: July 2021

NR‐INF‐02 is a standardized extract containing turmerosaccharides from Curcuma longa that has anti‐inflammatory, analgesic, and chondroprotective potential. In view of its potential uses, NR‐INF‐02 was evaluated for its safety in Wistar rats at an oral dose of 250, 500, and 1000 mg/kg in a 90‐day repeated dose subchronic toxicity study. NR‐INF‐02 administered at 250, 500, and 1000 mg/kg for 90 days did not show any mortality or clinical signs of toxicity. Body weight gain, food consumption, ocular and neurological examination, and hematological, blood biochemical, hormone, and urine analysis revealed no evidence of toxicity of NR‐INF‐02 treatment in rats. Absolute and relative organ weights were comparable to control rats. The study did not reveal any major treatment related gross pathological and histopathological alterations in the tissues or organs examined. Thus, based on study observations, the no‐observed adverse effect level (NOAEL) was found to be 1000 mg/kg body weight in albino Wistar rats.
Proactive Community Occupational Therapy Service for Social Participation Development of Thai Adults with Depression: A Grounded Theory Study from Occupational Therapists’ Perspective
Authors: Phadsri Supaluck , Shioji Rieko , Tanimura Atsuko , Apichai Sopida , Jaknissai Jeerawit
Published: July 2021

Introduction. Depression in adulthood decreases social participation in the workplace, family, and community, which further results in decreased work performance and cessation and social isolation. There is a high statistic of outpatient consultation and readmission of Thais with depression, yet the mental health support for remission in community life and social participation remains limited and unclear. Further, due to the lack of mental health professional resources, particularly occupational therapists, there is much to be known regarding how such therapists work to support the development of social participation in Thai adults with depression. Objective. This research was aimed at understanding the process of how occupational therapists work to redevelop the social participation of community-dwelling Thai adults with depression. Method. The grounded theory methodology was used in this study. Data were collected through interviews and nonparticipatory observations of 14 participants who had experience providing mental health care in community services. The constant comparative analysis method was employed. Result. Three concepts illustrated a proactive community occupational therapy service for depression (PCOTS-D), namely, integrating depression care in community occupational therapy service (COTS), supporting meaningful participation, and forming collaborative networks. The PCOTS-D supported the reconnection of social participation by leading from proactive depression care service to COTS and then working to support meaningful participation toward the patient’s self-management and building collaborative networks with inter- and intraprofessional teams simultaneously. Conclusion. The PCOTS-D presented a holistic view of working with community-dwelling Thai adults with depression by considering the importance of the community and researchers’ network to redevelop social participation, promote health and recovery, build teams in depression care, and encourage research evidence to enhance the supportive advocacy policy for Thai people with depression.
Perceived Pain during Rapid Maxillary Expansion (RME): Trends, Anatomical Distinctions, and Age and Gender Correlations
Authors: Serritella Emanuela , Migliaccio Stefania , Musone Ludovica , Impellizzeri Alessandra , De Stefano Adriana Assunta , Galluccio Gabriella
Published: July 2021

Objectives. To investigate pain trends and characteristics of different facial districts in patients undergoing rapid maxillary expansion (RME) and its possible correlations with age and gender. Materials and Methods. 85 subjects (45 males and 40 females) undergoing RME were selected and analyzed during first two weeks of treatment. Patients rated daily two types of pain perception: the general perceived pain (GPP), i.e., the pain overall perceived in the face, and the local perceived pain (LPP), i.e., the pain perceived locally in the following anatomical areas: anterior palate (APA), posterior palate (PPA), nasal (NA), joint (JA), and zygomatic (ZA). Patients were provided the Numeric Rating Scale (NRS) and Wong–Baker Faces Pain Rating Scale (FPS) to correctly assess their GPP and LPP. Pearson correlation coefficient and analysis of variance (ANOVA) were, respectively, used to define the linear relationship between all the variables considered and to verify whether the response variables (gender and age) were significantly different (α < 0.05). Results. Sample’s mean age was 10.11 years. Average pain values of GPP and LPP progressively rise from day 1 to days 2-3 (pain peak) and tended to decrease until day 14, with a linear decrease for GPP and a not linear decrease for LPP. PPA and APA resulted the most painful areas, followed, respectively, by JA, ZA, and NA. Statistically significant differences resulted in average pain values according to patients’ age and gender, both in GPP and LPP. Conclusion. RME causes perception of pain in several maxillofacial areas. Pain reported during RME resulted positively correlated with age and gender of patients.
Age and Sex Variation in the Duration of Action and Corneal Touch Threshold (CTT) following Instillation of 0.5% Topical Ophthalmic Proparacaine and Tetracaine Hydrochlorides
Authors: Kyei Samuel , Abaka Dadzie Nana Yaw , Zaabaar Ebenezer , Asamoah Dwomoh Kwasi Antwi , Asiedu Kofi
Published: July 2021

Purpose. We investigated the effect of age and sex on corneal touch threshold (CTT) and duration of action following administration of 0.5% topical ophthalmic proparacaine and tetracaine hydrochlorides. Methods. A prospective, randomized, subject-masked, crossover study design was used. Two hundred and forty human volunteers were enrolled in the study. Corneal touch threshold (CTT) was determined using a Cochet-Bonnet esthesiometer. CTT was measured every 15 seconds for the first 1-minute and at 5-minute intervals subsequently for a period of 40 minutes after the application of each anesthetic. CTT and duration of action of the ophthalmic solutions were tested for statistical significance using repeated measures ANOVA. Results. The total duration of effect was 20 minutes for females and 25 minutes for males for both anesthetics. The total duration of the effect of both solutions decreased with increasing age; however, elderly participants had the longest duration (5 minutes) of the maximal effect (minimum CTT) of the two ophthalmic preparations. There was a significant influence of sex, F (2.39, 569.65) = 2.86,

p
=
0.04

; F (3.48, 828.19) = 4.41,

p
=
0.003

, and age, F (4.78, 566.18) = 8.97,

p
<
0.001

; F (7.19, 852.56) = 20.55,

p
<
0.001

on CTT following application of proparacaine hydrochloride and tetracaine hydrochloride, respectively. Conclusion. CTT and duration of anesthetic effect after instillation of 1 drop of 0.5% proparacaine hydrochloride and 0.5% tetracaine hydrochloride vary based on sex and age.
The Molecular Epidemiology of Resistance to Antibiotics among Klebsiella pneumoniae Isolates in Azerbaijan, Iran
Authors: Kashefieh Mehdi , Hosainzadegan Hassan , Baghbanijavid Shabnam , Ghotaslou Reza
Published: July 2021

Introduction. Klebsiella pneumoniae (K. pneumoniae) is one of the leading causes of hospital-acquired and community-acquired infections in the world. This study was conducted to investigate the molecular epidemiology of drug resistance in clinical isolates of K. pneumoniae in Azerbaijan, Iran. Materials and Methods. A total of 100 nonduplicated isolates were obtained from the different wards of Azerbaijan state hospitals, Iran, from 2019 to 2020. Antibiotic susceptibility testing was done. The DNA was extracted, and the PCR for evaluation of the resistance genes was carried out. Results. The highest antibiotic resistance was shown to ampicillin (96%), and the highest susceptibility was shown to tigecycline (9%), and 85% of isolates were multidrug resistant. The most frequent ESBL gene in the tested isolates was blaSHV-1 in 58%, followed by blaCTXM-15 (55%) and blaSHV-11(42%). The qepA, oqxB, and oqxA genes were found to be 95%, 87.5%, and 70%, respectively. We detected tetB in 42%, tetA in 32%, tetD in 21%, and tetC in 16%. Seventy isolates were resistant to co-trimoxazole, and the rate of resistance genes was sul1 in 71%, followed by sul2 (43%), dfr (29%), and sul3 (7%). The most common aminoglycoside resistance genes were ant3Ia, aac6Ib, aph3Ib, and APHs in 44%, 32%, 32%, and 31.4%, respectively. The most frequent resistance gene to fosfomycin was fosA (40%) and fosX (40%) followed by fosC (20%). Conclusion. The results of this study indicate the high frequency of drug resistance among K. pneumoniae isolated from hospitals of Azerbaijan state. The present study shows the presence of high levels of drug-resistant genes in various antibiotics, which are usually used in the treatment of infections due to K. pneumoniae.
Revision with Locking Compression Plate by Compression Technique for Diaphyseal Nonunions of the Femur and the Tibia: A Retrospective Study of 54 Cases
Authors: Ding Peng , Chen Qiyu , Zhang Changqing , Yao Chen
Published: July 2021

Nonunion after diaphyseal fracture of the femur or the tibia is a common but difficult complication for treatment. Currently, the main treatment modalities include nail dynamization, exchange nailing, and bone transport, but revision with compression plating in these nonunions was rarely reported. To evaluate the outcomes of compression plating in the treatment of femur and tibia shaft nonunions, we retrospectively reviewed 54 patients with diaphyseal nonunion of the tibia or the femur treated with locking compression plate (LCP) by compression technique. There were 46 aseptic and 8 septic nonunions in the case series. Patient’s history, fracture characteristics, previous interventions, and types of nonunion were recorded. The possible reason which might lead to nonunion was also analyzed for each case. Patients with aseptic nonunions were revised by hardware removal and compression plating with or without bone grafting. For septic nonunions, a two‐stage surgery strategy was used. Compression plating with iliac crest bone grafting (ICBG) or free vascularized fibular grafting (FVFG) was used as the final treatment for septic nonunions. The compression technique and bone grafting method were individualized in each case according to the patient’s history and architecture of the nonunion. Each patient finished at least a two‐year follow‐up, and all cases achieved healing uneventfully. Our study showed that compression plating with LCP was an effective method to treat diaphyseal nonunions of the tibia and the femur. It is compatible with different bone grafting methods for both infected and noninfected nonunions and is a good alternative to the current treatment methods for these nonunions.
Effects of Simplified Antihypertensive Treatment Algorithm on Hypertension Management and Hypertension-Related Death in Resource-Constricted Primary Care Setting between 1997 and 2017
Authors: Heizhati Mulalibieke , Li Nanfang , Shi Qiaoyan , Yao Xiaoguang , Zhang Delian , Zhou Keming , Wang Menghui , Hu Junli , Duiyimuhan Gulinuer , Jiang Wen , Hong Jing , Sun Le
Published: July 2021

Hypertension management is poor in primary care settings of developing countries, where 75% of hypertensives are living. Exploring better ways to improve hypertension management and to decrease stroke and CVD death is needed such as introducing treatment algorithm. Therefore, we selected intervention counties from Xinjiang, an underdeveloped region in China, and introduced antihypertensive treatment algorithm, comprising locally available and affordable agents, to primary health providers since 1998. Program effects were evaluated using the data collected in various ways including cross-sectional screenings to population ≥30 years between 1998 and 2015 by comparing treatment and control rates of hypertension, changes in blood pressure (BP) levels and distribution, and proportion of case/total and NCD death for CVD and stroke. Compared to 1998–2000, treatment rate was improved by 2.78 fold (11.2% vs. 32.1%,

P

 < 0.001), and the overall and treated control rate were improved by 53.5 fold (0.2% vs. 10.7%,

P

 < 0.001) and by 16.8 fold (2.0% vs. 33.5%,

P

 < 0.001), respectively, in 2015. Mean SBP and DBP showed a net reduction by 33.7 mmHg (181.3 vs. 147.6 mmHg) and 21.3 mmHg (106.3 vs. 85.0 mmHg), respectively, in 2015, compared to 1998–2000 (

P

 < 0.001), and stage III hypertension was reduced by 75.2% (33.5 vs. 8.3%,

P

 < 0.001). Compared to 1997–1999, stroke/NCD death was reduced by 34.1% in 2015–2017 (31.7 vs. 20.9%,

P

 = 0.006) in the intervention counties whereas by 7.5% in control county. Introduction of treatment algorithm helps improve hypertension management and reduce stroke death in resource-constricted primary settings.
Probabilistic Design and Optimization for Tunnels considering Measuring Uncertainties
Authors: Jia Zhirong , Zhao Hongbo , Zhu Changxing
Published: July 2021

Uncertainty is an essential property of rock mechanics and engineering, which is of great significance to excavation, design, and control of rock engineering. In this study, an innovative framework of the reliability-based design was developed for the rock tunnel under uncertainty. The convergence-confinement method is used to characterize the interaction mechanism between the support structure and surrounding rock mass. Artificial bee colony (ABC) was adopted to solve the optimization problem in the reliability-based design. The probabilistic properties of rock strength and failure envelope were obtained based on the triaxial compression test data using the Bayesian method. The reliability of the tunnel and support structure was evaluated based on the abovementioned probabilistic properties of rock strength using the reliability analysis method. A circular tunnel was used to illustrate the developed framework, and the procedure was presented in detail. The time of rockbolt installed, the thickness of the shotcrete, length of rockbolt, circumferential space, and longitudinal space of rockbolt were determined and met the constraints of reliability index. Results show that the developed framework can consider the uncertainty for support design in the tunnel. It provides a good and promising way to support design considering the uncertainty of test data using the reliability-based design.
Analysis of Force Distribution of Four Rows of Bolts in Aircraft Fitting Joint
Authors: Sun Yifang , Grebenikov O. G. , Li Chenghu
Published: July 2021

With the help of 3D modeling software and finite element analysis software, the force distribution of four rows of bolts in the aircraft fitting joint is obtained in this paper. In 3D modeling software, the solid model is segmented according to the area and height of the center of gravity of the cross-section. In finite element analysis software, the beam elements are used to replace the segmented model to obtain the internal force applied at the end of the segmented model and the stress-strain state of each segment is calculated according to the internal force applied at the end of each segment. Finally, the force distribution of the four rows of bolts is obtained according to the average force difference on the center section between the bolt rows. In order to ensure the validity of this step-by-step calculation result, it was compared with the entire calculation result. It can be concluded that the force distribution of the two calculations is consistent. Under the working conditions of the fitting joint (130 MPa), the force distribution coefficients of the four rows of bolts are 0.182, 0.215, 0.197, and 0.12. Therefore, it is feasible to use the step-by-step method to calculate the force distribution of the four rows of bolts in the fitting joint. Compared with the entire calculation, the step-by-step calculation has the advantages of less calculation amount and faster calculation speed.
Can Smart City Policy Facilitate the Low‐Carbon Economy in China? A Quasi‐Natural Experiment Based on Pilot City
Authors: Fan Shuangshuang , Peng Shengnan , Liu Xiaoxue
Published: July 2021

This paper studies the impact of the implementation of smart city policy (SCP) on the development of low‐carbon economy (LCE) in China. For this purpose, we developed a nonconvex meta‐frontier data envelopment analysis (DEA) approach to measure LCE and used the differences‐in‐difference (DID) analysis method in the econometric model to empirically analyze the impact of SCP on LCE, using the dataset of 230 cities from 2005 to 2018. The results show that the implementation of SCP can significantly improve the LCE of cities, and the dynamic effect test presents that the promotion of smart cities to low‐carbon economy increases with time. In addition, SCP promotes the development of LCE by optimizing government functions and improving the efficiency of governance and the degree of implementation openness. But there is heterogeneity between different cities as follows: the implementation of SCP has a more significant effect on the promotion of LCE in central and western regions in China and large‐scale cities and cities without strict environmental protection planning. Finally, the robustness test verifies the reliability of the experimental data again and puts forward conclusions and policy recommendations.