bluuebunny/crossref_metadata_2025 huggingface dataset:
Study on the Flammability, Crystal Behaviors and Mechanical Performance of Polyamide 11 Composites by Intercalated Layered Double Hydroxides
Authors: Peng Cun , Yang Hua , Tang Wufei
Published: October 2022

Sulfamic acid-intercalated MgAl-LDH (SA-LDH) was prepared by an anion exchange method, and its structure was characterized by X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). SA-LDH was introduced into polyamide 11 (PA11) by melt blending and to enhance the flame retardancy and mechanical properties. The scanning electron microscope (SEM) and XRD data showed that the lamellar structure of SA-LDH was partly disrupted. The cone calorimeter (CCT) results demonstrated that SA-LDH could effectively decrease the value of heat release rate, which may be ascribed to the better distribution of SA-LDH compared to LHD in the PA11 matrix. The effects of SA-LDH on the crystal behaviors of PA11 were investigated by XRD and differential scanning calorimetry (DSC), indicating that SA-LDH could induce the formation of new crystal forms and served as a heterogeneous nucleating agent. The mechanical progress caused by the incorporation of SA-LDH was correlated with compatibility improvement between SA-LDH and PA11.
Three Heat Shock Protein Genes and Antioxidant Enzymes Protect Pardosa pseudoannulata (Araneae: Lycosidae) from High Temperature Stress
Authors: Fu Di , Liu Jing , Pan Ying-Na , Zhu Jia-Yun , Xiao Feng , Liu Min , Xiao Rong
Published: October 2022

Pardosa pseudoannulata (P. pseudoannulata) is an essential natural predatory enemy in rice ecosystems. The fluctuating climate may cause them to experience heat stress, whereas heat shock proteins (HSPs) and antioxidant enzymes help resist heat damage. Herein, we cloned and characterized the full-length genes PpHSP27, PpHSP60, and PpHSC70 from P. pseudoannulata. Changes in gene expression levels and superoxide dismutase (SOD), catalase (CAT), and glutathione transferase (GST) activities in adult male and female P. pseudoannulata were measured at different stress exposure times and temperatures. We found that the abovementioned HSP genes belong to the sHSP, HSP60, and HSP70 families. The expression of the three HSP genes and the activities of SOD, CAT, and GST were significantly upregulated with the increasing stress temperature and time. The knockdown of the three HSP genes via RNA interference significantly decreased the survival rate of male and female P. pseudoannulata during high temperature stress. Thus, PpHSP27, PpHSP60, and PpHSC70 play an important role in the heat tolerance of P. pseudoannulata, and SOD, CAT, and GST enable recovery heat stress-induced oxidative damage. Their changes and regulation during high temperature stress can improve spiders’ adaptability in the field and enhance the biological control of environmental pests.
Potential Antigenic Candidates for the Development of Peptide-Based Vaccines to Induce Immunization against Helicobacter pylori Infection in BALB/c Mice
Authors: AlEraky Doaa M. , Abuohashish Hatem M. , Bugshan Amr S. , Abdelsalam Maha M. , AlHawaj Hussain A. , AlKhamis Taleb T. , AlDossary Fatimah A. , Alrayes Nabras M. , Ragab Yasser M. , AbdelKhalek Zeinab , Helmy Omneya M. , Ramadan Mohammed A.
Published: October 2022

Helicobacter pylori (H. pylori) has been identified as a group-1 definite carcinogen. As of yet, there is no available vaccine for this microorganism. Our study aimed to identify antigenic peptides in H. pylori using an in silico proteomic approach, and to evaluate their effectiveness as potential vaccine candidates. Four different peptide sequences were prioritized using the reverse vaccinology, namely, CagA1, CagA2, VacA, and SabA. Peptides emulsified with Freunde’s adjuvant were used to immunize BALB/C mice. Subcutaneously immunized mice were challenged by oral administration of H. pylori. IgG, IgA, IL4, and IL17 were detected in mice sera. Histopathology of the dissected stomach of vaccinated and control mice were assessed using H&E stain. IgG was significantly higher in mice vaccinated with SabA. IL-4 was significantly increased in CagA1, CagA2, VacA, and SabA vaccinated mice compared to the adjuvant group. Additionally, histopathological examination of gastric tissue showed a protective effect in the vaccinated groups compared to adjuvant and PBS groups. Our findings indicate a promising effect of the tested epitopes, particularly the SabA antigen, to induce an immune response against H. pylori.
Structure-Based Virtual Screening and De Novo Design to Identify Submicromolar Inhibitors of G2019S Mutant of Leucine-Rich Repeat Kinase 2
Authors: Park Hwangseo , Kim Taeho , Kim Kewon , Jang Ahyoung , Hong Sungwoo
Published: October 2022

Missense mutations of leucine-rich repeat kinase 2 (LRRK2), including the G2019S mutant, are responsible for the pathogenesis of Parkinson’s disease. In this work, structure-based virtual screening of a large chemical library was carried out to identify a number of novel inhibitors of the G2019S mutant of LRRK2, the biochemical potencies of which ranged from the low micromolar to the submicromolar level. The discovery of these potent inhibitors was made possible due to the modification of the original protein–ligand binding energy function in order to include an accurate ligand dehydration energy term. The results of extensive molecular docking simulations indicated that the newly identified inhibitors were bound to the ATP-binding site of the G2019S mutant of LRRK2 through the multiple hydrogen bonds with backbone amide groups in the hinge region as well as the hydrophobic interactions with the nonpolar residues in the P-loop, hinge region, and interdomain region. Among 18 inhibitors derived from virtual screening, 4-(2-amino-5-phenylpyrimidin-4-yl)benzene-1,3-diol (Inhibitor 2) is most likely to serve as a new molecular scaffold to optimize the biochemical potency, because it revealed submicromolar inhibitory activity in spite of its low molecular weight (279.3 amu). Indeed, a highly potent inhibitor (Inhibitor 2n) of the G2019S mutant was derived via the structure-based de novo design using the structure of Inhibitor 2 as the molecular core. The biochemical potency of Inhibitor 2n surged to the nanomolar level due to the strengthening of hydrophobic interactions in the ATP-binding site, which were presumably caused by the substitutions of small nonpolar moieties. Due to the high biochemical potency against the G2019S mutant of LRRK2 and the putatively good physicochemical properties, Inhibitor 2n is anticipated to serve as a new lead compound for the discovery of antiparkinsonian medicines.
Integrated Transcriptome and Metabolome Analysis of Color Change and Low-Temperature Response during Flowering of Prunus mume
Authors: Dong Bin , Zheng Zifei , Zhong Shiwei , Ye Yong , Wang Yiguang , Yang Liyuan , Xiao Zheng , Fang Qiu , Zhao Hongbo
Published: October 2022

In China, Prunus mume is a famous flowering tree that has been cultivated for 3000 years. P. mume grows in tropical and subtropical regions, and most varieties lack cold resistance; thus, it is necessary to study the low-temperature response mechanism of P. mume to expand the scope of its cultivation. We used the integrated transcriptomic and metabolomic analysis of a cold-resistant variety of P. mume ‘Meiren’, to identify key genes and metabolites associated with low temperatures during flowering. The ‘Meiren’ cultivar responded in a timely manner to temperature by way of a low-temperature signal transduction pathway. After experiencing low temperatures, the petals fade and wilt, resulting in low ornamental value. At the same time, in the cold response pathway, the activities of related transcription factors up- or downregulate genes and metabolites related to low temperature-induced proteins, osmotic regulators, protective enzyme systems, and biosynthesis and metabolism of sugars and acids. Our findings promote research on the adaptation of P. mume to low temperatures during wintering and early flowering for domestication and breeding.
Gender Differences in microRNA Expressions as Related to Long-Term Graft Function in Kidney Transplant Patients
Authors: Ko Sien-Yu , Tsai Shang-Feng , Hsu Chia-Tien , Huang Shih-Ting , Chuang Ya-Wen , Yu Tung-Min , Wu Ming-Ju , Chen Cheng-Hsu
Published: October 2022

In recent studies, much has been discussed about biomarkers used in the evaluation of the transplanted graft function. However, there remains a lack of research regarding the long-term effects of microRNAs (miRNAs) on the different genders for kidney transplant (KTx) patients. In this study, we aim to assess the functions of miRNAs on long term outcomes of KTx patients by extracting differently expressed miRNAs between patients of normal graft function and graft dysfunction, while further analyzing their impact on the different genders. We analyzed the data of 40 patients who had received KTx for a period of more than ten years and included data regarding renal function, immuno-related markers and plasma miRNAs. Data were classified by gender for further studies. Twelve out of 17 females and 8 out of 23 males had undergone graft dysfunction. Renal function analysis showed significantly worse outcomes in the female patients. There were five differently expressed miRNAs between the female control group and female dysfunction group: miR-128-3p, miR-21-5p, miR-150-5p, miR-92a-3p and miR-15a-5p, and five between the male control group and male dysfunction group: miR-23a-3p, miR-126-3p, miR-142-3p, miR-223-3p and miR-26a-5p. Gender differences exist in incidences of kidney graft dysfunction, with male patients displaying better preservation in graft functions. Overall, these differently expressed miRNAs either enhance or suppress host immune responses. They can be predictive markers for graft survival and can also be important factors that lead to worse long term kidney graft function in females when compared to males.
Hereditary Disorders of Manganese Metabolism: Pathophysiology of Childhood-Onset Dystonia-Parkinsonism in SLC39A14 Mutation Carriers and Genetic Animal Models
Authors: Rodichkin Alexander N. , Guilarte Tomás R.
Published: October 2022

Over the last decade, several clinical reports have outlined cases of childhood-onset manganese (Mn)-induced dystonia-parkinsonism, resulting from loss-of-function mutations in the Mn influx transporter gene SLC39A14. These clinical cases have provided a wealth of knowledge on Mn toxicity and homeostasis. However, our current understanding of the underlying neuropathophysiology is severely lacking. The recent availability of Slc39a14 knockout (KO) murine and zebrafish animal models provide a powerful platform to investigate the neurological effects of elevated blood and brain Mn concentrations in vivo. As such, the objective of this review was to organize and summarize the current clinical literature and studies utilizing Slc39a14-KO animal models and assess the validity of the animal models based on the clinical presentation of the disease in human mutation carriers.
Prevention and Treatment of Obesity-Related Inflammatory Diseases by Edible and Medicinal Plants and Their Active Compounds
Authors: Saad Bashar
Published: October 2022

Obesity, defined by excessive fat mass and its associated low-grade chronic inflammation, leads to insulin resistance, diabetes, and metabolic dysfunctions. The immunomodulatory properties of natural agents have gained much interest in recent decades. Some of the plant-derived agents are known to be immunomodulators that can affect both innate and adaptive immunity, e.g., thymoquinone, curcumin, punicalagin, resveratrol, quercetin, and genistein. Natural immunomodulators may contribute to the treatment of a number of inflammatory diseases, as they have significant efficacy and safety profiles. The immunomodulatory effects of traditional Greco-Arab and Islamic diets and medicinal plants are well acknowledged in abundant in vitro studies as well as in animal studies and clinical trials. This review highlights the role of Greco-Arab and Islamic diets and medicinal plants in the management of inflammation associated with obesity. Although previously published review articles address the effects of medicinal plants and phytochemicals on obesity-related inflammation, there is no systematic review that emphasizes clinical trials of the clinical significance of these plants and phytochemicals. Given this limitation, the objective of this comprehensive review is to critically evaluate the potential of the most used herbs in the management of obesity-related inflammation based on clinical trials.
Detection of Chitin Synthase Mutations in Lufenuron-Resistant Spodoptera frugiperda in China
Authors: Lv Sheng-Lan , Xu Zheng-Yi , Li Ming-Jian , Mbuji Amosi Leonard , Gu Meng , Zhang Lei , Gao Xi-Wu
Published: October 2022

Spodoptera frugiperda (J. E. Smith), is commonly known as fall armyworm, native to tropical and subtropical regions of America, is an important migratory agricultural pest. It is important to understand the resistance and internal mechanism of action of S. frugiperda against lufenuron in China. Lufenuron is one of the main insecticides recommended for field use in China and has a broad prospect in the future. We conducted a bioassay using the diet-overlay method and found that the current S. frugiperda in China are still at a low level of resistance to lufenuron. Secondly, we examined whether the mutation I1040M (I1042M in Plutella xylostella), associated with lufenuron resistance, was produced in the field. And then we tested the expression of chitin synthase SfCHSA and SfCHSB in different tissues, and the changes of these two genes after lufenuron induction. The results showed that there is still no mutation generation in China and there is a significant change in the expression of SfCHSA under the effect of lufenuron. In conclusion, our study suggests that field S. frugiperda populations in 2019 and 2020 were less resistant to lufenuron. In fall armyworm, chitin synthases included SfCHSA and SfCHSB genes, and after induction treatment with lufenuron, the expression of the SfCHSA gene was significantly increased. In SfCHSA, no mutation has been detected in the site associated with lufenuron resistance. Secondly, in S. frugiperda larvae, the SfCHSA gene was the highest in the head of the larvae, followed by the integument; while the SfCHSB gene was mainly concentrated in the midgut. Therefore, we believe that the SfCHSA gene plays a greater role in the resistance of S. frugiperda to lufenuron than the SfCHSB gene. It is worth noting that understanding the level of resistance to lufenuron in China, the main mechanism of action of lufenuron on larvae, and the mechanism of resistance to lufenuron in S. frugiperda will help in crop protection as well as in extending the life span of this insecticide.
Genome-Wide Screening for Pathogenic Proteins and microRNAs Associated with Parasite–Host Interactions in Trypanosoma brucei
Authors: Yang Zhiyuan , Shi Mai , Zhang Xiaoli , Yao Danyu
Published: October 2022

Tsetse flies are a type of blood-sucking insect living in diverse locations in sub-Saharan Africa. These insects can transmit the unicellular parasite Trypanosoma brucei (T. brucei) which causes African trypanosomiasis in mammals. There remain huge unmet needs for prevention, early detection, and effective treatments for this disease. Currently, few studies have investigated the molecular mechanisms of parasite–host interactions underlying African trypanosomiasis, mainly due to a lack of understanding of the T. brucei genome. In this study, we dissected the genomic and transcriptomic profiles of T. brucei by annotating the genome and analyzing the gene expression. We found about 5% of T. brucei proteins in the human proteome, while more than 80% of T. brucei protein in other trypanosomes. Sequence alignment analysis showed that 142 protein homologs were shared among T. brucei and mammalian genomes. We identified several novel proteins with pathogenic potential supported by their molecular functions in T. brucei, including 24 RNA-binding proteins and six variant surface glycoproteins. In addition, 26 novel microRNAs were characterized, among which five miRNAs were not found in the mammalian genomes. Topology analysis of the miRNA-gene network revealed three genes (RPS27A, UBA52 and GAPDH) involved in the regulation of critical pathways related to the development of African trypanosomiasis. In conclusion, our work opens a new door to understanding the parasite–host interaction mechanisms by resolving the genome and transcriptome of T. brucei.
Colchicine in Cardiac Surgery: The COCS Randomized Clinical Trial
Authors: Shvartz Vladimir , Le Tatyana , Enginoev Soslan , Sokolskaya Maria , Ispiryan Artak , Shvartz Elena , Nudel Daria , Araslanova Naylyana , Petrosyan Andrey , Donakanyan Sergey , Chernov Igor , Bockeria Leo , Golukhova Elena
Published: October 2022

Background. In patients who underwent cardiac surgery, first-time postoperative atrial fibrillation (POAF) is associated with increased incidence of hospital-acquired complications and mortality. Systemic inflammation is one of confirmed triggers of its development. The anti-inflammatory properties of colchicine can be effective for the POAF prevention. However, the results of several studies were questionable and required further investigation. Hence, we aimed to evaluate the effectiveness of low-dose short-term colchicine administration for POAF prevention in patients after the open-heart surgery. This double-blind randomized placebo-controlled trial included 267 patients, but 27 of them dropped out in the course of the study. Study subjects received the test drug on the day before the surgery and on postoperative days 2, 3, 4 and 5. The rhythm control was conducted immediately after the operation and until the discharge from the hospital. The final analysis included 240 study subjects: 113 in the colchicine group and 127 in the placebo group. POAF was observed in 21 (18.6%) patients of the colchicine group vs. 39 (30.7%) control patients (OR 0.515; 95% Cl 0.281–0.943; p = 0.029). We observed no statistically significant differences between the patient groups in the secondary endpoints of the study (hospital mortality, respiratory failure, stroke, bleeding, etc.). For other parameters characterizing the severity of inflammation (pericardial effusion, pleural effusion, WBC count, neutrophil count), there were statistically significant differences between the groups in the early postoperative period (days 3 and 5). Also, statistically significant differences between the groups in the frequency of adverse events were revealed: the incidence of diarrhea in the colchicine group was 25.7% vs. 11.8% in the placebo group (OR 2.578; 95% Cl 1.300–5.111; p = 0.005); for abdominal pain, incidence values were 7% vs. 1.6%, correspondingly (OR 4.762; 95% Cl 1.010–22.91; p = 0.028). Thus, there were statistically significant differences between groups in the primary endpoint, thereby confirming the effectiveness of short-term colchicine use for the POAF prevention after coronary artery bypass grafting and/or aortic valve replacement. Also, we detected statistically significant differences between groups in the frequency of side effects to colchicine: diarrhea and abdominal pain were more common in the colchicine group. This clinical trial is registered with ClinicalTrials database under a unique identifier: NCT04224545.
Clinical Management of Pathogen-Negative Tuberculous Meningitis in Adults: A Series Case Study
Authors: He Yuqin , Huang Yanzhu , Wu Di , Wu Yingying , Wang Minghuan
Published: October 2022

Tuberculosis remains a serious world public health problem. Tuberculous meningitis (TBM) is the one of most severe forms of extrapulmonary tuberculosis. However, the insensitivity and time-consuming requirement of culturing the pathogen Mycobacterium tuberculosis, the traditional “gold standard” diagnostic test for TBM, often delays timely diagnosis and treatment, resulting in high disability and mortality rates. In our series case study, we present five pathogen-negative TBM cases who received empirical anti-tuberculosis therapy with a good clinical outcome. We describe in detail the clinical symptoms, laboratory test results, and imaging findings of the five patients from symptom onset to dynamic follow-up. We then summarize the similarities of the clinical characteristics of the presented patients, as well as shared features in laboratory and imaging tests, and proceed to analyze the challenges in the timely diagnosis of TBM. Finally, we argue that monitoring of cerebrospinal fluid markers and imaging are critical for the diagnosis and treatment of TBM, and emphasize the importance of differential diagnosis in cases when tuberculous meningitis is highly suspected despite negative findings for that etiology.
Evaluation of Effects of Various Irrigating Solutions on Chemical Structure of Root Canal Dentin Using FTIR, SEM, and EDS: An In Vitro Study
Authors: Padmakumar Indu , Hinduja Dharam , Mujeeb Abdul , Kachenahalli Narasimhaiah Raghu , Kumar Saraswathi Ashwini , Mirza Mubashir Baig , Robaian Ali , Basheer Syed Nahid , Karobari Mohmed Isaqali , Scardina Giuseppe Alessandro
Published: October 2022

Background: Sequential chemical application for irrigating a root canal during chemomechanical debridement can affect the dentin microstructure. Understanding the effects of various irrigants on chemical properties of dentin can elucidate their effects on physical properties and thereby explain the higher incidence of structural failure in endodontically treated teeth. This in vitro research aimed to compare and evaluate the effects of three different irrigating solutions on the chemical structure of root canal dentin in extracted human teeth. Methods: Forty-eight extracted single-rooted mandibular premolar teeth were sectioned at the cemento–enamel junction by a diamond disc and were then randomly assigned to four groups of twelve samples each. The groups were irrigated using 5.25% NaOCl, ozonated olive oil, silver citrate, or distilled water. Dentin sections measuring 1.5 mm were obtained from the root portion and each section and were analyzed using Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and electron-dispersive spectroscopy (EDS). FTIR and EDS values are reported as means ± standard deviations. Data were analyzed using an ANOVA and a post hoc Bonferroni test (p < 0.05). Results: A comparison of the FTIR and EDS values among the groups using ANOVA revealed statistically significant differences in the organic and inorganic peak values among the groups. An intergroup comparison between NaOCl with silver citrate and ozonated olive oil revealed significant reductions in the carbonate and phosphate peak values in the NaOCl group (p < 0.05). The EDS values tabulated for the carbon, oxygen, phosphorous, and calcium peak levels showed significant differences between the groups using an ANOVA. An SEM analysis was conducted under 1500× magnification, which revealed smear layer removal in the silver citrate group. Conclusions: The silver citrate solution and the ozonated olive oil caused less changes in the organic and mineral contents of dentin than sodium hypochlorite.
The Relationship between Training Cycle-Dependent Fluctuations in Resting Blood Lactate Levels and Exercise Performance in College-Aged Rugby Players
Authors: Kano Ryotaro , Sato Kohei
Published: October 2022

An increase in resting blood lactate (La−) concentration due to metabolic conditions has been reported. However, it is not clear whether resting La− changes with training cycles in athletes. The purpose of this study was to test the hypotheses that (1) the morning resting La− levels are lower in periods of high training compared to periods of low training and (2) these changes in La− concentration are related to athletes’ metabolic capacity during exercise in male college-aged rugby players. Resting La− and blood glucose concentrations were measured in the morning in eight league rugby players during the summer pre-season period (Pre-period), the training and competition season period (TC-period), and the winter post-season period (Post-period). In each period, anaerobic power, La− concentration, and respiratory responses were measured during the 40 s maximal Wingate anaerobic test (WT). The resting La− concentration in the morning was significantly lower in the TC-Period (1.9 ± 0.6 mmol/L) than in the Post-Period (2.3 ± 0.9 mmol/L). The rate of decrease in La− level immediately after the 40 s WT was significantly higher in the TC-Period than in the Post-Period. The resting La− concentration was significantly correlated with the peak oxygen uptake and the carbon dioxide output during the WT. These results support the hypothesis that an athlete’s training cycle (i.e., in season and off season) influences the resting La− levels as well as the metabolic capacity during high-intensity exercise. The monitoring of resting La− fluctuations may provide a convenient indication of the training cycle-dependent metabolic capacity in athletes.
Biological Predictors of Treatment Response in Adult Attention Deficit Hyperactivity Disorder (ADHD): A Systematic Review
Authors: Capuzzi Enrico , Caldiroli Alice , Auxilia Anna Maria , Borgonovo Riccardo , Capellazzi Martina , Clerici Massimo , Buoli Massimiliano
Published: October 2022

Background: Attention-deficit/hyperactivity disorder (ADHD) is a highly prevalent condition with onset in childhood and in many cases persisting into adulthood. Even though an increasing number of studies have investigated the efficacy of pharmacotherapy in the management of adult ADHD, few authors have tried to identify the biological predictors of treatment response. Objectives: To summarize the available data about the biological markers of treatment response in adults affected by ADHD. Methods: A search on the main biomedical and psychological archives (PubMed, Embase, Scopus, and PsycINFO) was performed. Manuscripts in English, published up to May 2022 and having the biological predictors of treatment response in adults with ADHD as their main topic, were included. Results: A total of 3855 articles was screened. Twenty-two articles were finally included. Most of the manuscripts studied neuroimaging and electrophysiological factors as potential predictors of treatment response in adult ADHD patients. No reliable markers were identified until now. Promising findings on this topic regard genetic polymorphisms in snap receptor (SNARE) proteins and default mode network-striatum connectivity. Conclusions: Even though some biological markers seem promising for the prediction of treatment response in adults affected by ADHD, further studies are needed to confirm the available data in the context of precision medicine.
Money Attitude and Spiritual Well-Being
Authors: Pong Hok-Ko
Published: October 2022

This study seeks to explore the relationship between money attitude and spiritual well-being amongst Chinese youths in Hong Kong. Cross-sectional data (N = 501) were obtained from 249 Chinese university students in 2021 and 252 Chinese university students in 2022, aged between 19–23 years old. The participants were instructed to answer the Spiritual Well-being Questionnaire (SWBQ) to measure their spiritual well-being in the personal-communal, environmental and transcendental domains. The respondents were then asked to complete the Money Attitude Scale (MAS) to assess their attitudes and beliefs regarding money in three dimensions: power-prestige, anxiety and distrust. Results show that a negative correlation exists between the three dimensions of money attitude and the three domains of spiritual well-being. In addition, the power–prestige dimension of money attitude was the most accurate predictor of spiritual well-being. A stepwise regression analysis unveiled that the power-prestige dimension of students’ money attitudes explained 6.2%, 15.4% and 27.6% of the variance in their sense of spiritual well-being across the personal-communal, environmental and transcendental domains, respectively. Adopting healthy perspectives and attitudes towards money are vital for the development of the youths’ (spiritual) well-being. Thus, financial education and knowledge are crucial for adolescents.
Competitive Policy for Online Retailers’ Intrusion in E-Commence
Authors: Han Feiyan , Chen Sheng , Li Bo
Published: October 2022

In recent years, online retail has developed rapidly. However, as consumer demands become increasingly sophisticated, the traditional online retail model has encountered difficulties with respect to meeting consumers’ needs. As a result, numerous retailers with offline physical stores have emerged in the online retail industry. This paper constructs a game model for the invasion of the market by e-commerce retailers with offline physical stores in a context in which a traditional, online-only incumbent retailer is already in the market. Compared with the new entrant, the incumbent has the advantage of an established good reputation, and consumers prefer the products of the incumbent. This research shows that as consumers’ product valuations increase, the following three situations may occur: a partially covered market, a multiple-equilibrium market or a fully covered market. In a partially covered market, the incumbency advantage does not affect the entrant. In a multiple-equilibrium market or fully covered market, the incumbency advantage impacts the profits of the entrant. However, in a fully covered market, if the incumbency advantage is too large, the profits of both retailers are damaged. Finally, this paper finds that offline physical stores can provide positive benefits to entrants. When consumers are highly sensitive to services, opening offline physical stores is an effective intrusion strategy that entrants can use to overcome the incumbency advantage.
Assessment of Agricultural Areas Suitable for Agroforestry in Latvia
Authors: Bārdulis Andis , Ivanovs Jānis , Bārdule Arta , Lazdiņa Dagnija , Purviņa Dana , Butlers Aldis , Lazdiņš Andis
Published: October 2022

The role of trees on agricultural land is predicted to increase rapidly in order to achieve biodiversity, environmental, and climate goals. This study demonstrated the selection and evaluation approach and assessed the suitable agricultural land for agroforestry practices in hemiboreal Latvia, which was selected as the demonstration area by synthesizing knowledge of environmental sciences, remote sensing, and relevant legislation on land use and management. The total area of agricultural land suitable for agroforestry was estimated to be 14.1% of the total agricultural land in Latvia (351.5 kha). The selected agricultural land mainly comprised semihydromorphic soils; the dominant soil texture was loamy sand. Current dominant land use in the selected agricultural land consisted of heterogeneous agriculture and pastures; however, the selected agricultural parcels were outside intensive agricultural production for the most part—only 0.38% of the total selected agricultural land was accepted to receive state support and/or EU support to farmers under the Common Agricultural Policy (CAP). Considering the lengthy process of implementation of new agricultural-land-management practices, as well as taking into account the ambitious timeframe for reaching biodiversity, environmental, and climate goals, we recommend reducing hindrances to the introduction of agroforestry systems. The provided selection and evaluation approach is transferable to other countries and regions by adaptation of the elaborated methodologies to available country-specific spatial information and data
Agricultural Location and Crop Choices in China: A Revisitation on Von Thünen Model
Authors: Han Hongyun , Yuan Zhen , Zou Kai
Published: October 2022

Growing populations and rapid urbanization have put tremendous pressure on the food supply. The rural hinterland around cities is an important source of the urban food supply chain. Facing the constraints of China’s land stock, reasonable use of land space and optimization of agricultural crop structure is crucial to meet the food demand. Von Thünen Model, which is fronted by a 19th-century German economist, outlines a rural landscape of commercial farmers growing agricultural products for local markets while proposing basic patterns and principles of land use in agriculture. Using data from China’s OVOP (“One village, One product”), this paper analyzes the agricultural location and crop choices around two levels of cities (provincial capital cities, and county-level cities) by using Thünen’s theory. The results showed that crop density did decrease as the distance to urban increased. Crop rings are present in the vicinity of both metropolitan and county-level cities, distributed according to crop intensity. Evidence from China suggests that agricultural location and crop selection still follow the basic principles of the Thünen model. Planners and policymakers should refocus on the Von Thünen model to utilize land space and optimize agricultural production scientifically and efficiently.
One-Step Synthesis of LiCo1-1.5xYxPO4@C Cathode Material for High-Energy Lithium-ion Batteries
Authors: Wang Yue , Qiu Jingyi , Li Meng , Zhu Xiayu , Wen Yuehua , Li Bin
Published: October 2022

Intrinsically low ion conductivity and unstable cathode electrolyte interface are two important factors affecting the performances of LiCoPO4 cathode material. Herein, a series of LiCo1-1.5xYxPO4@C (x = 0, 0.01, 0.02, 0.03) cathode material is synthesized by a one-step method. The influence of Y substitution amount is optimized and discussed. The structure and morphology of LiCo1-1.5xYxPO4@C cathode material does not lead to obvious changes with Y substitution. However, the Li/Co antisite defect is minimized and the ionic and electronic conductivities of LiCo1-1.5xYxPO4@C cathode material are enhanced by Y substitution. The LiCo0.97Y0.02PO4@C cathode delivers a discharge capacity of 148 mAh g−1 at 0.1 C and 96 mAh g−1 at 1 C, with a capacity retention of 75% after 80 cycles at 0.1 C. Its good electrochemical performances are attributed to the following factors. (1) The uniform 5 nm carbon layer stabilizes the interface and suppresses the side reactions with the electrolyte. (2) With Y substitution, the Li/Co antisite defect is decreased and the electronic and ionic conductivity are also improved. In conclusion, our work reveals the effects of aliovalent substitution and carbon coating in LiCo1-1.5xYxPO4@C electrodes to improve their electrochemical performances, and provides a method for the further development of high voltage cathode material for high-energy lithium-ion batteries.
Non-Destructive Detection of Real Defects in Polymer Composites by Ultrasonic Testing and Recurrence Analysis
Authors: Ciecieląg Krzysztof , Kęcik Krzysztof , Skoczylas Agnieszka , Matuszak Jakub , Korzec Izabela , Zaleski Radosław
Published: October 2022

This paper presents results of ultrasonic non-destructive testing of carbon fibre-reinforced plastics (CFRPs) and glass-fibre reinforced plastics (GFRPs). First, ultrasonic C-scan analysis was used to detect real defects inside the composite materials. Next, the composite materials were subjected to drilling in the area of defect formation, and measured forces were used to analyse the drilling process using recurrence methods. Results have confirmed that recurrence methods can be used to detect defects formed inside a composite material during machining.
Gallium Oxide for Gas Sensor Applications: A Comprehensive Review
Authors: Zhu Jun , Xu Zhihao , Ha Sihua , Li Dongke , Zhang Kexiong , Zhang Hai , Feng Jijun
Published: October 2022

Ga2O3 has emerged as a promising ultrawide bandgap semiconductor for numerous device applications owing to its excellent material properties. In this paper, we present a comprehensive review on major advances achieved over the past thirty years in the field of Ga2O3-based gas sensors. We begin with a brief introduction of the polymorphs and basic electric properties of Ga2O3. Next, we provide an overview of the typical preparation methods for the fabrication of Ga2O3-sensing material developed so far. Then, we will concentrate our discussion on the state-of-the-art Ga2O3-based gas sensor devices and put an emphasis on seven sophisticated strategies to improve their gas-sensing performance in terms of material engineering and device optimization. Finally, we give some concluding remarks and put forward some suggestions, including (i) construction of hybrid structures with two-dimensional materials and organic polymers, (ii) combination with density functional theoretical calculations and machine learning, and (iii) development of optical sensors using the characteristic optical spectra for the future development of novel Ga2O3-based gas sensors.
Effect of Fiber-Matrix Interface on the Mechanical Response of a Woven Carbon Fiber/PEEK Composite Material
Authors: Toro Sebastián Andrés , Ridruejo Alvaro , González Carlos , Fernández Blázquez Juan Pedro
Published: October 2022

This work studies the relationship between the interface shear strength (IFSS) and the mechanical response of a carbon fiber-reinforced composite with a polyether-ether-ketone (PEEK) thermoplastic matrix. Two types of laminates were studied: the first kind was manufactured with as-received fiber fabrics, while specimens belonging to the second one were fabricated with thermally treated fibers where the original sizing agent was removed. IFSS values were measured with the push-in test, showing that treated fibers exhibit a 25% higher critical shear stress. Microscopic inspection of the laminates revealed that untreated specimens were prone to debonding, generating a much higher crack density. This difference was detected by the C-Scan technique and triggered in the response of both laminates under tensile tests at ±45∘ fiber orientation, where maximum stress and strain at break values of desized specimens showed an increase of 37% and 190%, respectively. Results confirmed that the original fiber sizing weakened the fiber-matrix interface. Lastly, the tensile response of the composite is analyzed in light of interface quality.
Preparation and Basic Properties of Praseodymium-Neodymium-Chromium Containing Imitation Gemstone Glass
Authors: Zhang Siqi , Li Keqing , Pu Junyuan , Ni Wen
Published: October 2022

Imitation gemstone glass has numerous characteristics, including low cost, rich colour, stable colouring, and the formation of colour-changing effects that can meet the jewellery market demand for beautiful gemstones of middle and low grades. In this study, four types of gem-imitating glass were prepared by the elemental substitution of praseodymium, neodymium and chromium elements based on rare earth glass and examined by combining refractive index, density, spectral characteristics and colour parameters. Sample 1 contained only Pr6O11 and showed a golden-yellow colour like chrysoberyl. Sample 2 contained only Nd2O3 and showed a blue-purple colour like amethyst. Sample 3 contained Pr6O11 and Nd2O3 and appeared green under D65 light source and red under A light source, with a colour-change effect like alexandrite. Sample 4 contained Pr6O11, Nd2O3 and Cr2O3 and showed a highly saturated green colour like emerald because of the strong colouring effect of Cr3+ in the glass. The findings revealed that all four samples are transparent, with a refractive index greater than 1.5 and a density higher than 2.6 g/cm3. The comprehensive performance of the four imitation gemstone glasses can be found in the corresponding natural gemstones, which has a certain practical value.
Effect of Superhydrophobic Coating and Nanofiller Loading on Facial Elastomer Physical Properties
Authors: Aulia Rahmi Khairani , Beatty Mark W. , Simetich Bobby
Published: October 2022

Facial prosthetics are currently constructed of materials that are far from optimal; superior materials with a “skin-like” feel are required. In this study, the property changes brought about by the consecutive additions of hydrophobic- and uncoated nano-SiO2 to polydimethylsiloxane (PDMS) are assessed, and the alterations are compared with those observed for conventional submicron SiO2-filled materials. In sequence, 0%, 0.5%, 5%, 10%, and 15% by weight of each filler type were successively added to vinyl-terminated PDMS. Tensile, tear, Durometer hardness, translucency, and viscoelastic properties were assessed, and hardness and translucency were further measured after 3000 h of outdoor weathering. The results showed that 15% coated nano- SiO2-filled PDMS materials given the highest tensile strength, elastic modulus, storage modulus, loss modulus, tear strength, and durometer hardness (p < 0.05), whereas 15% submicron coated SiO2-filled materials displayed the highest failure strain and translucency parameter (p < 0.05). Only 10%- and 15%-filled submicron SiO2 PDMS materials were altered by outdoor weathering; nevertheless, the increases were assessed to be too small to be clinically perceptible. As increased filler levels provided protection against solar radiation, heat, and moisture, only unfilled and 0.5%-filled PDMS formulations discolored from weathering. 15%-filled superhydrophobic-coated nano- SiO2-filled PDMS was found to produce the strongest, most tear-resistant, and least translucent materials, but it also produced materials with limited stretchability and high hardness, which were regarded to be downsides for creating a “skin-like” feel.
Fracture Strain of Al–Si-Coated Press-Hardened Steels under Plane-Strain Bending
Authors: Hou Zeran , Song Wei , Yi Hongliang , Wang Jianfeng , Min Junying
Published: October 2022

Press-hardened steel (PHS) is widely applied to fabricate vehicle body structures for attaining mass reduction and fuel economy without sacrificing occupant safety. The VDA bendability test is often used to characterize the fracture resistance of PHS under plane-strain bending conditions. As lightweighting continues to be a design imperative in the automotive industry, it is desirable to develop and adopt more press-hardened components with higher fracture resistance. In this work, four Al–Si-coated 22MnB5 steels with various initial thicknesses and coating weights were studied. A newly developed methodology was used to calculate the fracture limit strain under plane-strain bending. The results indicate that although the four investigated 22MnB5 steels exhibit similar tensile properties under uniaxial tension, their bending performance per the VDA 238-100 standard differs significantly. The PHS with a low coating weight possesses a higher bending angle and, hence, a larger fracture limit strain. Meanwhile, the peak bending force can be 10% higher than the PHS with a standard coating weight at the same sheet thickness. Therefore, it is expected that PHS with higher fracture strain will have the potential for lightweighting due to its enhanced resistance to fracture and higher energy absorption capability.
An Experimental Study on Non-Destructive Evaluation of the Mechanical Characteristics of a Sustainable Concrete Incorporating Industrial Waste
Authors: Umar Tariq , Yousaf Muhammad , Akbar Muhammad , Abbas Nadeem , Hussain Zahoor , Ansari Wajahat Sammer
Published: October 2022

Structural materials sustainability is gaining popularity across the globe at present. Reusing natural resources, building, demolition debris, and solid waste are the most apparent tools to make construction more environmentally friendly. Traditional concrete is believed to be less durable, stronger, environmentally friendly, and socially and commercially feasible than industrial waste concrete. The evolution of non-destructive testing (NDT) across time has not been investigated in depth by researchers. An experimental study was carried out to propose the use of non-destructive mechanisms that would enable us to assess concrete’s compressive strength without causing destruction. Varying quantities of industrial waste (coal bottom ash (CBA) and waste glass sludge (WGS)) were incorporated to cast concrete prisms (150 mm × 150 mm × 150 mm). The results obtained helped us to establish relationships between the compressive strength of concrete and the Schmidt hammer rebound value, as well as the ultrasonic pulse velocities. Microstructural analysis showed that incorporating 10% of CBA and WGS improved the porosity of concrete specimens, which shows the applicability of these industrial wastes as partial cement replacements. Scanning electron microscopy (SEM) showed traces of calcium alumino-silicate hydrate (C-A-S-H), portlandite and C-S-H, which indicates the binder characteristics of CBA and WGS. The concept of the response surface approach (RSM) for optimizing cement and industrial waste substitution was validated by the polynomial work expectation. The model was statistically significant when the fluctuation of ANOVA was analyzed using a p value with a significance level of 0.05. The study results show that the usage of 15% CBA and 10% WGS as a cementitious additive and cement replacement has the potential to increase the strength of concrete significantly.
Excitation Wavelength and Colloids Concentration-Dependent Nonlinear Optical Properties of Silver Nanoparticles Synthesized by Laser Ablation
Authors: Mohamed Tarek , El-Motlak Majed H. , Mamdouh Samar , Ashour Mohamed , Ahmed Hanan , Qayyum Hamza , Mahmoud Alaa
Published: October 2022

We reported experimental results from investigations that employed the Z-scan method to explore the dependence of silver nanoparticles’ (AgNPs) nonlinear optical properties on the excitation wavelength, AgNP concentration, and size. Using a 532 nm Nd: YAG laser beam at 100 mJ/pulse for different ablation times, AgNPs were synthesized from a silver target immersed in distilled water. UV–Vis spectroscopy and an atomic absorption spectrometer are used to characterize the optical properties of laser-synthesized AgNPs as well as their concentrations. The AgNPs’ size and shape are determined using a transmission electron microscope (TEM). The laser-synthesized AgNPs are spherical, with an average particle size of 12 to 13.2 nm. Whatever the ablation time, the AgNP colloids exhibit reversed saturable absorption and a negative nonlinear refractive index (n2). Both n2 and the nonlinear absorption coefficient (α3) increase as the AgNP concentration increases. As the excitation wavelength and average size of the AgNPs increase, n2 and α3 decrease.
Proton Transport in the Gadolinium-Doped Layered Perovskite BaLaInO4
Authors: Tarasova Nataliia , Bedarkova Anzhelika , Animitsa Irina
Published: October 2022

Materials capable for use in energy generation have been actively investigated recently. Thermoelectrics, photovoltaics and electronic/ionic conductors are considered as a part of the modern energy system. Layered perovskites have many attractions, as materials with high conductivity. Gadolinium-doped layered perovskite BaLaInO4 was obtained and investigated for the first time. The high values of conductivity were proved. The composition BaLa0.9Gd0.1InO4 demonstrates predominantly protonic transport under wet air and low temperatures (<400 °C). The doping by rare earth metals of layered perovskite is a prospective method for significantly improving conductivity.