bluuebunny/crossref_metadata_2025 huggingface dataset:
Scaling Analysis of Shear Thickening Suspensions
Authors: Malbranche Nelya , Santra Aritra , Chakraborty Bulbul , Morris Jeffrey F.
Published: July 2022

Dense suspensions of particles in viscous liquid often demonstrate the striking phenomenon of abrupt shear thickening, where their viscosity increases strongly with increase of the imposed stress or shear rate. In this work, discrete-particle simulations accounting for short-range hydrodynamic, repulsive, and contact forces are performed to simulate flow of shear thickening bidisperse suspensions, with the packing parameters of large-to-small particle radius ratio δ = 3 and large particle fraction ζ = 0.15, 0.50, and 0.85. The simulations are carried out for volume fractions 0.54 ≤ ϕ ≤ 0.60 and a wide range of shear stresses. The repulsive forces, of magnitude FR, model the effects of surface charge and electric double-layer overlap, and result in shear thinning at small stress, with shear thickening beginning at stresses σ ∼ FRa−2. A crossover scaling analysis used to describe systems with more than one thermodynamic critical point has recently been shown to successfully describe the experimentally-observed shear thickening behavior in suspensions. The scaling theory is tested here on simulated shear thickening data of the bidisperse mixtures, and also on nearly monodisperse suspensions with δ = 1.4 and ζ = 0.50. Presenting the viscosity in terms of a universal crossover scaling function between the frictionless and frictional maximum packing fractions collapses the viscosity for most of the suspensions studied. Two scaling regimes having different exponents are observed. The scaling analysis shows that the second normal stress difference N2 and the particle pressure Π also collapse on their respective curves, with the latter featuring a different exponent from the viscosity and normal stress difference. The influence of the fraction of frictional contacts, one of the parameters of the scaling analysis, and its dependence on the packing parameters are also presented.
Analysis of Factors Affecting Individuals’ Online Consumer Credit Behavior: Evidence From China
Authors: Zhao Huiying , Peng Huaxin , Li Wanqi
Published: July 2022

In the past two decades, a growing number of Chinese young adults utilize online consumer credit to satisfy their increasing consumption demand. Although it is indeed boosting consumer markets, it has also caused many serious social problems. A number of previous studies discussed the authentication mechanism and legal supervision of online lending from a legal or economic perspective, and a small number of scholars explored factors affecting individuals’ online consumer credit from the perspective of behavioral psychology. Based on the Triandis model and existing studies on online lending, this paper constructs a theoretical model for the formation of individuals’ online consumer credit. It then adopts SmartPLS 3.00 to analyze the data set that involves 302 respondents in total. This research found that affect, facilitating conditions, perceived consequences and social factors have a significant impact on individuals’ online consumer credit. The findings of this study have political and practical implications. First, they can contribute to the rational consumption by China’s young generation and promote the sound development of online consumer credit. In the meantime, this study also helps online consumer credit platforms to provide better services and improve public relations.
Knowledge, Attitude, and Practices Toward Tuberculosis Among Hospital Outpatients in Kabul, Afghanistan
Authors: Essar Mohammad Yasir , Rezayee Khalid Jan , Ahmad Shoaib , Kamal Manar Ahmed , Nasery Reshaduddin , Danishmand Tamim Jan , Head Michael , Nemat Arash
Published: July 2022

Background

Tuberculosis (TB) is a high-burden respiratory infectious disease. There was a sharp decline in the number of confirmed TB cases during the pandemic; this is likely to be influenced by the COVID-19 pandemic response, with under-reporting due to resource diversion. There are typically 13,000 tuberculosis-associated deaths in Afghanistan annually, with significant problems posed by drug-resistant TB.

Method

A cross-sectional descriptive study was conducted in Afghanistan on Kabul residents who visited the adult outpatient departments of public hospitals for any health-related reason from 1st January to 20th March 2022. The study scored their knowledge, attitude, and practices (KAP) toward tuberculosis. The sample size was calculated using Epi-Info, and the minimum sample size was 385. The sampling method is chosen the non-probability convenient sampling for data gathering. Data were analyzed using SPSS version 28, and we used the Mann-Whitney test, Chi-square or fisher extract test, spearman correlations, and binary logistic regression model.

Results

Of 829 participants, 450 (54.3%) were males and 379 (45.7) females. The median age was 28 years, and 63.3% were married. Most participants were unemployed (75.5%), but 54% had a monthly income >3,000 Afghanis, indicating the reliance on family. By TB knowledge score, 727 (87.7%) participants had good knowledge, and 800 (96.5%) participants had a positive attitude toward treatment and control. Only 2 participants reported poor practices regarding prevention. Regarding the binary logistic regression, young age, being a male, belonging to the “1,000–3,000” Afghani monthly income category, and having a positive attitude were significant predictors of good TB knowledge (P-value = 0.009, 0.000, 0.003, and 0.009), respectively. A positive attitude was expected to have good knowledge 6.035 times more than a negative attitude (95% CI: 1.572–23.167).

Conclusion

The study findings highlighted that outpatients in Kabul had good knowledge, attitude, and practice toward TB. More studies are needed to highlight KAP in different Afghan populations, including in other parts of the country.
Mandibular Reconstruction With the Contralateral Vascularized Iliac Flap Using Individual Design: Iliac Crest Used to Reconstruct the Ramus and the Anterior Border of the Iliac Wing Used to Reconstruct the Inferior Border: A Case Report
Authors: Xu Guangcai , Jia Ju , Xiong Xuepeng , Peng Liwei , Bu Lin-lin , Wang Xiqian
Published: July 2022

Mandible defects resulting from resection of benign or malignant lesions, trauma, or radionecrosis are commonly encountered in the oral and maxillofacial department. Vascularized bone flaps, in general, provide the best functional and aesthetic outcome. The iliac crest provides a large piece of curved cortico-cancellous bone, measuring 6–16 cm in length. It has a natural curvature that complements the curve of the lateral and sometimes anterior mandible and can be placed accordingly to fill defects. In the paper, we report a mandibular reconstruction with a vascularized iliac flap using individual virtual preoperative planning and 3D printing technology. We want to offer a new design idea for mandibular defect reconstruction.
Research on Network Attack Traffic Detection HybridAlgorithm Based on UMAP-RF
Authors: Du Xiaoyu , Cheng Cheng , Wang Yujing , Han Zhijie
Published: July 2022

Network attack traffic detection plays a crucial role in protecting network operations and services. To accurately detect malicious traffic on the internet, this paper designs a hybrid algorithm UMAP-RF for both binary and multiclassification network attack detection tasks. First, the network traffic data are dimensioned down with UMAP algorithm. The random forest algorithm is improved based on parameter optimization, and the improved random forest algorithm is used to classify the network traffic data, distinguishing normal data from abnormal data and classifying nine different types of network attacks from the abnormal data. Experimental results on the UNSW-NB15 dataset, which are significant improvements compared to traditional machine-learning methods, show that the UMAP-RF hybrid model can perform network attack traffic detection effectively, with accuracy and recall rates of 92.6% and 91%, respectively.
The Role of Curcumin in Prostate Cancer Cells and Derived Spheroids
Authors: Boccellino Mariarosaria , Ambrosio Pasqualina , Ballini Andrea , De Vito Danila , Scacco Salvatore , Cantore Stefania , Feola Antonia , Di Donato Marzia , Quagliuolo Lucio , Sciarra Antonella , Galasso Giovanni , Crocetto Felice , Imbimbo Ciro , Boffo Silvia , Di Zazzo Erika , Di Domenico Marina
Published: July 2022

A major challenge in the clinical management of prostate cancer (PC) is to inhibit tumor growth and prevent metastatic spreading. In recent years, considerable efforts have been made to discover new compounds useful for PC therapy, and promising advances in this field were reached. Drugs currently used in PC therapy frequently induce resistance and PC progresses toward metastatic castration-resistant forms (mCRPC), making it virtually incurable. Curcumin, a commercially available nutritional supplement, represents an attractive therapeutic agent for mCRPC patients. In the present study, we compared the effects of chemotherapeutic drugs such as docetaxel, paclitaxel, and cisplatin, to curcumin, on two PC cell lines displaying a different metastatic potential: DU145 (moderate metastatic potential) and PC-3 (high metastatic potential). Our results revealed a dose-dependent reduction of DU145 and PC-3 cell viability upon treatment with curcumin similar to chemotherapeutic agents (paclitaxel, cisplatin, and docetaxel). Furthermore, we explored the EGFR-mediated signaling effects on ERK activation in DU145 and PC-3 cells. Our results showed that DU145 and PC-3 cells overexpress EGFR, and the treatment with chemotherapeutic agents or curcumin reduced EGFR expression levels and ERK activation. Finally, chemotherapeutic agents and curcumin reduced the size of DU145 and PC-3 spheroids and have the potential to induce apoptosis and also in Matrigel. In conclusion, despite different studies being carried out to identify the potential synergistic curcumin combinations with chemopreventive/therapeutic efficacy for inhibiting PC growth, the results show the ability of curcumin used alone, or in combinatorial approaches, to impair the size and the viability of PC-derived spheroids.
Intraarterial Therapies for the Management of Hepatocellular Carcinoma
Authors: Garg Tushar , Shrigiriwar Apurva , Habibollahi Peiman , Cristescu Mircea , Liddell Robert P. , Chapiro Julius , Inglis Peter , Camacho Juan C. , Nezami Nariman
Published: July 2022

Image-guided locoregional therapies play a crucial role in the management of patients with hepatocellular carcinoma (HCC). Transarterial therapies consist of a group of catheter-based treatments where embolic agents are delivered directly into the tumor via their supplying arteries. Some of the transarterial therapies available include bland embolization (TAE), transarterial chemoembolization (TACE), drug-eluting beads–transarterial chemoembolization (DEB–TACE), selective internal radioembolization therapy (SIRT), and hepatic artery infusion (HAI). This article provides a review of pre-procedural, intra-procedural, and post-procedural aspects of each therapy, along with a review of the literature. Newer embolotherapy options and future directions are also briefly discussed.
Assessment of Changes in Key Ecosystem Factors and Water Conservation with Remote Sensing in the Zoige
Authors: Hou Peng , Zhai Jun , Jin Dian-Dian , Zhou Yan , Chen Yan , Gao Hai-Feng
Published: July 2022

As the largest alpine peat swamp wetland distribution area in the world, the Zoige has important ecological functions, including water conservation and biodiversity maintenance. In the past 20 years, the regional ecological protection and restoration measures continuously strengthened under the leadership of the local government have led to gradual improvements in the ecological environment of the region. In this study, multisource satellite remote-sensing image data were used to carry out quantitative monitoring and assessment of the main ecological elements (vegetation and water), as well as the regional leading ecosystem service function in the Zoige. Combined with local ecological protection management policies and measures, we analyzed the characteristics and effectiveness of ecological protection. We compared the ecosystem change trends of the Zoige reserve and the county, from 2001 to 2020, and found that the fractional vegetation cover (FVC) of Zoige county has increased at a rate of 0.25%/year. The growth rate was highest between 2015 and 2020, and the growth rate of FVC in the Zoige Wetland National Nature Reserve is approximately 1.89-fold that of the whole county. The water area also shows similar variation characteristics. On the whole, the water conservation capacity of the Zoige showed a significant increase from 2001 to 2020. We used high-resolution satellite remote-sensing images to capture the details of land use changes brought about by local ecological protection policies and measures, and together with macroecological indicators, we reflected on the effectiveness of regional ecological protection measures. We observed that the ecological effects of nature reserves are more direct and rapid, and the amount of water conservation within the nature reserve is about 1 × 104 m3/km2 higher than that of the surrounding grasslands. Satellite remote-sensing images can not only capture the multiscale change information of ecological indicators, such as vegetation and water, in a timely manner, but can also help us to identify the effectiveness of conservation measures by distinguishing and analyzing the causes of these changes.
Bird Communities Vary under Different Urbanization Types—A Case Study in Mountain Parks of Fuzhou, China
Authors: Xu Weizhen , Fu Weicong , Dong Jiaying , Yu Jiao , Huang Peilin , Zheng Dulai , Chen Ziru , Zhu Zhipeng , Ding Guochang
Published: July 2022

Bird habitats are becoming increasingly fragmented as a result of rapid urbanization. As one of the essential refuges for urban bird communities, mountain parks are of practical significance for studying the spatial changes of birds, which can inform the future planning of mountain park planning. In this study, we assessed the α, β, and functional diversity of bird communities in mountain parks in Fuzhou, China, at three levels of urbanization (urban, peri-urban, suburban) and explored how diversity (abundance, richness, α-diversity, Chao1) varies along the urbanization gradient. A three-month bird survey was conducted using the transect method to examine the impact of urbanization on bird community structures in mountain parks. In addition, we evaluated the functional diversity of bird guilds in order to identify potential indicator species for monitoring different urbanization gradients in mountain parks. The results showed that: (1) During the three bird surveys from December 2021 to February 2022, 96 bird species and 2429 individuals of 9 orders, 34 families, and 63 genera were identified. (2) Urbanization had a significant impact on the overall bird α-diversity (p = 0.040) and richness (p = 0.024) but not on the overall bird abundance (p = 0.056). (3) The results of non-metric multidimensional scaling showed significant variations among overall birds in mountain parks along with three urbanization levels (stress = 0.155, p = 0.027). Similarly, significant differences were observed in the upper-stratum guild (stress = 0.183, p = 0.049) but not in other diet and vertical foraging stratum guilds. (4) Five species were identified as potential candidates for monitoring the trends of urban gradients. Moreover, compared to insectivorous or omnivorous guilds, most carnivorous and herbivorous guilds may not be suitable for monitoring the negative effects of urbanization in mountain parks. Our findings can help inform urban mountain park management or restoration strategies intended to mitigate the adverse impacts of urbanization.
Correlation between the Concentration of Secondary Metabolites and Soil Microorganisms in Sophora Koreensis Nakai from Different Habitat
Authors: Lee Hwa , Cheong Eun Ju
Published: July 2022

Sophora koreensis is an endemic species of Gangwon-do, Korea, that has a variety of applications for foods and for folk remedies. Here this research analyzed and compared compounds present in leaves, stems, and roots of S. koreensis collected from three different habitats in Chuncheon, Inje and Yanggu in South Korea. This research also analyzed soil microorganisms present in the three habitats to determine the correlation between the compound and microorganisms. N-methylcytisine was the most common compound in all three habitats, but the amounts varied with Chuncheon having the highest amount (509 mg/L), followed by Yanggu and Inje(102 mg/L and 39 mg/L, respectively). The composition of microorganisms also varied by habitat. Yanggu, Inje, and Chuncheon had 1013, 973, and 814 taxa, respectively. According to the phylogenetic relations, the composition of the soil microorganisms in Chuncheon was significantly different from the other two. It contained more PAC000121_g (Solibacteres), major taxa in all three habitats (14% in Chuncheon). In contrast less Opitutus minor taxa was found than Yannggu and Inje. The correlation between the soil microorganism N-methylcytisine was analyzed. Among these microorganisms, Paraburkholderia had a positive correlation with N-methylcytisine. Meanwhile, Rhizomicrobium, CP011215_f (Paceibacter), KB906767_g (Solibacteres) and Opitutus negatively correlated with N-methylcytisine. The results suggested that soil microorganisms in the habitats influenced the variations of the N-methylcytisine.
Impact of Selected Environmental Factors on Variation in Leaf and Branch Traits on Endangered Karst Woody Plants of Southwest China
Authors: Zhang Chen , Zeng Fuping , Zeng Zhaoxia , Du Hu , Su Liang , Zhang Lijin , Lu Mengzhen , Zhang Hao
Published: July 2022

We explored the adaptability of endangered plants in degraded karst habitats through functional trait variation, using three endangered woody plants (E. cavaleriei, H. bodinieri and K. septentrionalis) in karst peak-cluster depression. We investigated the variation decomposition and correlation analysis of 13 branch and leaf functional traits using a mixed linear model, variance decomposition, Pearson’s correlation analysis, random forest regression, and generalized linear regression. The degree of variation in phosphorus concentration in the branches was the highest, while that in the carbon concentration in the leaves was the smallest. The variation in the carbon concentration in the branches and leaves, and the dry matter concentration in the leaves was mainly within species, while the variation in other functional traits was mainly between species. We found significant correlations among leaf traits, branch traits, and leaf–branch traits to different degrees; however, there were no significant correlations among branch traits in H. bodinieri. The significant correlations were higher in E. cavaleriei and K. septentrionalis than in H. bodinieri. Plant functional traits were influenced by soil and topographic factors, and the relationship between them varied by species. Our findings will enhance our understanding of the variation in leaf and branch traits in karst endangered plants and the adaptative strategies of endangered plants in degraded habitat, and will provide a scientific basis for vegetation conservation in the karst region of southwest China.
Canopy Transpiration and Stomatal Conductance Dynamics of Ulmus pumila L. and Caragana korshinskii Kom. Plantations on the Bashang Plateau, China
Authors: Zhang Yu , Li Wei , Yan Haiming , Xie Baoni , Zhao Jianxia , Wang Nan , Wang Xiaomeng
Published: July 2022

Constructing protective forests to control water and soil erosion is an effective measure to address land degradation in the Bashang Plateau of North China, but forest dieback has occurred frequently due to severe water deficits in recent decades. However, transpiration dynamics and their biophysical control factors under various soil water contents for different forest functional types are still unknown. Here, canopy transpiration and stomatal conductance of a 38-year-old Ulmus pumila L. and a 20-year-old Caragana korshinskii Kom. were quantified using the sap flow method, while simultaneously monitoring the meteorological and soil water content. The results showed that canopy transpiration averaged 0.55 ± 0.34 mm d−1 and 0.66 ± 0.32 mm d−1 for U. pumila, and was 0.74 ± 0.26 mm d−1 and 0.77 ± 0.24 mm d−1 for C. korshinskii in 2020 and 2021, respectively. The sensitivity of canopy transpiration to vapor pressure deficit (VPD) decreased as soil water stress increased for both species, indicating that the transpiration process is significantly affected by soil drought. Additionally, canopy stomatal conductance averaged 1.03 ± 0.91 mm s−1 and 1.34 ± 1.22 mm s−1 for U. pumila, and was 1.46 ± 0.90 mm s−1 and 1.51 ± 1.06 mm s−1 for C. korshinskii in 2020 and 2021, respectively. The low values of the decoupling coefficient (Ω) showed that canopy and atmosphere were well coupled for both species. Stomatal sensitivity to VPD decreased with decreasing soil water content, indicating that both U. pumila and C. korshinskii maintained a water-saving strategy under the stressed water conditions. Our results enable better understanding of transpiration dynamics and water-use strategies of different forest functional types in the Bashang Plateau, which will provide important insights for planted forests management and ecosystem stability under future climate changes.
Global Value Chain Participation and Green Innovation: Evidence from Chinese Listed Firms
Authors: Meng Shuang , Yan Huan , Yu Jiajie
Published: July 2022

Green innovation is one of the most important approaches to prevent environmental pollution and foster sustainable development. Embedded in the global production networks, manufacturing firms have been found not only to be the main drivers of innovation but also the main polluters in developing countries. However, relatively few studies have systematically considered the effect of global value chain (GVC) participation on green innovation in the context of developing countries. By using a panel dataset of Chinese listed manufacturing firms, this study conducts panel data fixed-effect analyses and uses the instrumental variable two-stage least square model to investigate the effect of GVC participation on firms’ green innovation performance. The results show that increased GVC participation leads to improved green innovation performance of Chinese firms. Meanwhile, further heterogeneity analyses show that the impact of GVC participation on green innovation is more pronounced for firms with greater financial constraints, state-owned firms and firms in labor- or pollution-intensive industries, located in the eastern regions of China. Therefore, this study sheds light on the implication that actively participating in GVC is the key to promoting sustainable growth when facing the need for transformation in developing countries.
Organizational Factors Associated with Evidence-Based Practice Knowledge, Attitudes, and Implementation among Nurses in Saudi Arabia
Authors: Alqahtani Naji , Oh Kyeung M. , Kitsantas Panagiota , Rodan Margaret , Innab Adnan , Asiri Saeed , Kerari Ali , Bin Hayyan Fayez , Alharbi Mohammad , Bahari Ghareeb
Published: July 2022

Evidence-based practice (EBP) is crucial in keeping nurses aware of the current knowledge and improving clinical decision-making. The integration of nurses’ EBP competencies and organizational support has been suggested to create an effective arena in implementing EBP. The purpose of the study was to examine organizational factors influencing nurses’ EBP knowledge, attitudes, and implementation and identify staff nurses’ perceptions of EBP nursing leadership and hospital supports in Saudi Arabia. Data were collected from a convenience sample of staff nurses (N = 227) working in four hospitals using a cross-sectional, correlational descriptive design. Level of education (p < 0.05), EBP training (p < 0.05), unit type (ICU (p < 0.001) and ER (p < 0.01)), perceived nursing leadership (p < 0.001), and work environment (p < 0.05) supports were found significantly associated with nurses’ knowledge. Magnet recognition (p < 0.01) and knowledge (p < 0.001) had significant influence on nurses’ attitudes. Unit type (ER) (p < 0.05), knowledge (p < 0.001), and attitudes (p < 0.001) were associated with implementation. Encouragement to attend EBP trainings from nursing leadership was perceived by most nurses (51.1%). Nurses reported their hospitals support EBP through training (68.2%). Findings support the need for healthcare systems to create a culture that facilitates EBP implementation to enhance nurses’ EBP competencies and improve patients’ outcomes. Nursing managers may consider preparing nurses through education.
Pan-Genome Analysis of Oral Bacterial Pathogens to Predict a Potential Novel Multi-Epitopes Vaccine Candidate
Authors: Rida Tehniyat , Ahmad Sajjad , Ullah Asad , Ismail Saba , Tahir ul Qamar Muhammad , Afsheen Zobia , Khurram Muhammad , Saqib Ishaq Muhammad , Alkhathami Ali G. , Alatawi Eid A. , Alrumaihi Faris , Allemailem Khaled S.
Published: July 2022

Porphyromonas gingivalis is a Gram-negative anaerobic bacterium, mainly present in the oral cavity and causes periodontal infections. Currently, no licensed vaccine is available against P. gingivalis and other oral bacterial pathogens. To develop a vaccine against P. gingivalis, herein, we applied a bacterial pan-genome analysis (BPGA) on the bacterial genomes that retrieved a total number of 4908 core proteins, which were further utilized for the identification of good vaccine candidates. After several vaccine candidacy analyses, three proteins, namely lytic transglycosylase domain-containing protein, FKBP-type peptidyl-propyl cis-trans isomerase and superoxide dismutase, were shortlisted for epitopes prediction. In the epitopes prediction phase, different types of B and T-cell epitopes were predicted and only those with an antigenic, immunogenic, non-allergenic, and non-toxic profile were selected. Moreover, all the predicted epitopes were joined with each other to make a multi-epitopes vaccine construct, which was linked further to the cholera toxin B-subunit to enhance the antigenicity of the vaccine. For downward analysis, a three dimensional structure of the designed vaccine was modeled. The modeled structure was checked for binding potency with major histocompatibility complex I (MHC-I), major histocompatibility complex II (MHC-II), and Toll-like receptor 4 (TLR-4) immune cell receptors which revealed that the designed vaccine performed proper binding with respect to immune cell receptors. Additionally, the binding efficacy of the vaccine was validated through a molecular dynamic simulation that interpreted strong intermolecular vaccine–receptor binding and confirmed the exposed situation of vaccine epitopes to the host immune system. In conclusion, the study suggested that the model vaccine construct has the potency to generate protective host immune responses and that it might be a good vaccine candidate for experimental in vivo and in vitro studies.
Frailty Risk Prediction Model among Older Adults: A Chinese Nation-Wide Cross-Sectional Study
Authors: Li Siying , Fan Wenye , Zhu Boya , Ma Chao , Tan Xiaodong , Gu Yaohua
Published: July 2022

Objectives: Numerous studies have been performed on frailty, but rarely do studies explore the integrated impact of socio-demographic, behavioural and social support factors on frailty. This study aims to establish a comprehensive frailty risk prediction model including multiple risk factors. Methods: The 2018 wave of the Chinese Longevity and Health Longitudinal Survey was used. Univariate and multivariate logistic regressions were performed to identify the relationship between frailty and multiple risk factors and establish the frailty risk prediction model. A nomogram was utilized to illustrate the prediction model. The area under the receiver operating characteristic curve (AUC), Hosmer–Lemeshow test and calibration curve were used to appraise the prediction model. Results: Variables from socio-demographic, social support and behavioural dimensions were included in the final frailty risk prediction model. Risk factors include older age, working as professionals and technicians before 60 years old, poor economic condition and poor oral hygiene. Protective factors include eating rice as a staple food, regular exercise, having a spouse as the first person to share thoughts with, doing physical examination once a year and not needing a caregiver when ill. The AUC (0.881), Hosmer–Lemeshow test (p = 0.618), and calibration curve showed that the risk prediction model was valid. Conclusion: Risk factors from socio-demographic, behavioural and social support dimensions had a comprehensive effect on frailty, further supporting that a comprehensive and individualized intervention is necessary to prevent frailty.
Impact of the COVID-19 Pandemic on Pulmonary Hypertension Patients: Insights from the BNP-PL National Database
Authors: Mamzer Aleksandra , Waligora Marcin , Kopec Grzegorz , Ptaszynska-Kopczynska Katarzyna , Kurzyna Marcin , Darocha Szymon , Florczyk Michal , Mroczek Ewa , Mularek-Kubzdela Tatiana , Smukowska-Gorynia Anna , Wrotynski Michal , Chrzanowski Lukasz , Dzikowska-Diduch Olga , Perzanowska-Brzeszkiewicz Katarzyna , Pruszczyk Piotr , Skoczylas Ilona , Lewicka Ewa , Blaszczak Piotr , Karasek Danuta , Kusmierczyk-Droszcz Beata , Mizia-Stec Katarzyna , Kaminski Karol , Jachec Wojciech , Peregud-Pogorzelska Malgorzata , Doboszynska Anna , Gasior Zbigniew , Tomaszewski Michal , Pawlak Agnieszka , Zablocka Wieslawa , Ryczek Robert , Widejko-Pietkiewicz Katarzyna , Kasprzak Jaroslaw D.
Published: July 2022

We aimed to evaluate the clinical course and impact of the SARS-CoV-2 pandemic on the rate of diagnosis and therapy in the complete Polish population of patients (pts) with pulmonary arterial hypertension (PAH-1134) and CTEPH (570 pts) treated within the National Health Fund program and reported in the national BNP-PL database. Updated records of 1704 BNP-PL pts collected between March and December 2020 were analyzed with regard to incidence, clinical course and mortality associated with COVID-19. Clinical characteristics of the infected pts and COVID-19 decedents were analyzed. The rates of new diagnoses and treatment intensification in this period were studied and collated to the proper intervals of the previous year. The incidence of COVID-19 was 3.8% (n = 65) (PAH, 4.1%; CTEPH, 3.2%). COVID-19-related mortality was 28% (18/65 pts). Those who died were substantially older and had a more advanced functional WHO class and more cardiovascular comorbidities (comorbidity score, 4.0 ± 2.1 vs. 2.7 ± 1.8; p = 0.01). During the pandemic, annualized new diagnoses of PH diminished by 25–30% as compared to 2019. A relevant increase in total mortality was also observed among the PH pts (9.7% vs. 5.9% pre-pandemic, p = 0.006), whereas escalation of specific PAH/CTEPH therapies occurred less frequently (14.7% vs. 21.6% pre-pandemic). The COVID-19 pandemic has affected the diagnosis and treatment of PH by decreasing the number of new diagnoses, escalating therapy and enhancing overall mortality. Pulmonary hypertension is a risk factor for worsened course of COVID-19 and elevated mortality.
The Paradoxical Effects of COVID-19 Event Strength on Employee Turnover Intention
Authors: Deng Hui , Wu Wenbing , Zhang Yihua , Zhang Xiaoyan , Ni Jing
Published: July 2022

As a global pandemic, the novel coronavirus (COVID-19) has brought enormous challenges to employees and organizations. Although numerous existing studies have highlighted that the COVID-19 pandemic is a stressful event and empirically proved its detrimental effect on employee turnover intention, few scholars have noted that this pandemic can deteriorate the external economic and employment environment simultaneously, which may further complicate employees’ intentions to leave or stay in the current organization. Drawing on event system theory and social cognitive theory, this study aims to uncover two potential cognitive mechanisms of the complex impact of COVID-19 event strength on employee turnover intention. To examine the proposed model, this study employed a three-wave and time-lagged research design and collected data from a sample of 432 employees of four Chinese companies from different industries. The findings indicated that COVID-19 event strength was negatively related to perceived external employability, and ultimately curbed employee turnover intention. Yet, COVID-19 event strength also negatively predicted perceived organizational growth, thus influencing employees to exhibit intentions to quit. Moreover, organizational identification not only attenuated the positive effect of perceived external employability on turnover intention but also amplified the negative impact of perceived organizational growth on turnover intention. Further, organizational identification moderated the indirect effects of COVID-19 event strength on turnover intention through perceived external employability and perceived organizational growth. This study provided a comprehensive insight into scholars’ understanding of the COVID-19 downstream outcomes.
Effects of Physical Activity Interventions on Health Outcomes among Older Adults Living with HIV: A Systematic Review and Meta-Analysis
Authors: Shim Mi-So , Noh Dabok
Published: July 2022

There is a lack of evidence regarding the effects of exercise on older individuals living with HIV. This systematic review and meta-analysis examined previous studies on physical activity interventions for people living with HIV aged ≥50 years. The effectiveness of the interventions on various physical and psychological health outcomes was evaluated. Databases used for this review included PubMed, EMBASE, CINAHL, and Cochrane Library CENTRAL. Twelve randomized controlled trials on physical activity interventions for people ≥50 years and living with HIV were included. Standardized mean differences were calculated using random-effect models. All effect sizes were expressed using Cohen’s d values and their 95% confidence intervals (CIs). Physical activity interventions had a significant effect on walking capacity (Cohen’s d: 0.467; 95% CI [0.069, 0.865]). The effect sizes on cardiorespiratory fitness, weight, and health-related quality of life were not significant. These findings suggest that physical activity interventions for people living with HIV aged ≥50 years are effective for the improvement of walking capacity. Further larger and higher-quality studies are required to determine the full effects of physical activity interventions on various health outcomes among older adults with HIV.
Moving toward Smart Manufacturing with an Autonomous Pallet Racking Inspection System Based on MobileNetV2
Authors: Hussain Muhammad , Chen Tianhua , Hill Richard
Published: July 2022

Pallet racking is a fundamental component within the manufacturing, storage, and distribution centers of companies around the World. It requires continuous inspection and maintenance to guarantee the protection of stock and the safety of personnel. At present, racking inspection is manually carried out by certified inspectors, leading to operational down-time, inspection costs and missed damage due to human error. As companies transition toward smart manufacturing, we present an autonomous racking inspection mechanism using a MobileNetV2-SSD architecture. We propose a solution that is affixed to the adjustable cage of a forklift truck, enabling adequate coverage of racking in the immediate vicinity. Our proposed approach leads to a classifier that is optimized for deployment onto edge devices, providing real-time alerts of damage to forklift drivers, with a mean average precision of 92.7%.
Preparation and Characterization of Novel Microgels Containing Nano-SiO2 and Copolymeric Hydrogel Based on Poly (Acrylamide) and Poly (Acrylic Acid): Morphological, Structural and Swelling Studies
Authors: Sorkhabi Tannaz Soltanolzakerin , Samberan Mehrab Fallahi , Ostrowski Krzysztof Adam , Majka Tomasz M. , Piechaczek Marcin , Zajdel Paulina
Published: July 2022

In this paper, novel microgels containing nano-SiO2 were prepared by in situ copolymerization using nano-SiO2 particles as a reinforcing agent, nanosilica functional monomer (silane-modified nano-SiO2) as a structure and morphology director, acrylamide (AAm) as a monomer, acrylic acid (AAc) as a comonomer, potassium persulfate (KPS) as a polymerization initiator, and N,N′-methylene bis (acrylamide) (MBA) as a crosslinker. In addition, a conventional copolymeric hydrogel based on poly (acrylamide/acrylic acid) was synthesized by solution polymerization. The microgel samples, hydrogel and nanoparticles were characterized by transmission electron microscopy (TEM), field emission scanning electron microscopy (FESEM), Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). A FESEM micrograph of copolymeric hydrogel showed the high porosity and 3D interconnected microstructure. Furthermore, FESEM results demonstrated that when nano-SiO2 particles were used in the AAm/AAc copolymerization process, the microstructure and morphology of product changed from porous hydrogel to a nanocomposite microgel with cauliflower-like morphology. According to FESEM images, the copolymerization of AAm and AAc monomers with a nanosilica functional monomer or polymerizable nanosilica particle as a seed led to a microgel with core–shell structure and morphology. These results demonstrated that the polymerizable vinyl group on nano-SiO2 particles have controlled the copolymerization and the product morphology. FTIR analysis showed that the copolymeric chains of polyacrylamide (PAAm) and poly (acrylic acid) (PAAc) were chemically bonded to the surfaces of the nano-SiO2 particles and silane-modified nano-SiO2. The particulate character of microgel samples and the existence of long distance among aggregations of particles led to rapid swelling and increasing of porosity and therefore increasing of degree of swelling.
The Study of New NiTi Actuators to Reinforce the Wing Movement of Aircraft Systems
Authors: Braga Rafael , Rodrigues Patrícia Freitas , Cordeiro Hélder , Carreira Pedro , Vieira Maria Teresa
Published: July 2022

Actuators using Shape Memory Alloy (SMA) springs could operate in different mechanical systems requiring geometric flexibility and high performance. The aim of the present study is to highlight the potential of these actuators, using their dimensional variations resulting from the phase transformations of NiTi springs (SMA) to make the movements of the system’s mobile components reversible. This reversibility is due to thermal-induced martensitic transformation of NiTi springs. The transformation promotes the extended and retracted of the springs as the phase changing (martensite–austenite) creates movement in part of the system. Therefore, the phase transition temperatures of NiTi, evaluated by differential scanning calorimetry (DSC), are required to control the dimensional variation of the spring. The influence of the number of springs in the system, as well as how impacts on the reaction time were evaluated. The different numbers of springs (two, four, and six) and the interspaces between them made it possible to control the time and the final angle attained in the mobile part of the system. Mechanical resistance, maximum angle, and the system’s reaction time using different NiTi springs highlight the role of the actuators. Fused Deposition Modelling (FDM)/Material Extrusion (MEX) or Selective Laser Sintering (SLS) was selected for shaping the composite matrix system. A new prototype was designed and developed to conduct tests that established the relationship between the recoverable deformation of the matrix suitable for the application as well as the number and distribution of the actuators.
Cast Microstructure of a Complex Concentrated Noble Alloy Ag20Pd20Pt20Cu20Ni20
Authors: Simić Lidija , Rudolf Rebeka , Majerič Peter , Anžel Ivan
Published: July 2022

A complex concentrated noble alloy (CCNA) of equiatomic composition (Ag20Pd20Pt20Cu20Ni20–20 at. %) was studied as a potential high—performance material. The equiatomic composition was used so that this alloy could be classified in the subgroup of high—entropy alloys (HEA). The alloy was prepared by induction melting at atmospheric pressure, using high purity elements. The degree of metastability of the cast state was estimated on the basis of changes in the microstructure during annealing at high temperatures in a protective atmosphere of argon. Characterisation of the metallographically prepared samples was performed using a scanning electron microscope (SEM) equipped with an energy dispersive spectrometer (EDS), differential scanning calorimetry (DSC), and X–ray diffraction (XRD). Observation shows that the microstructure of the CCNA is in a very metastable state and multiphase, consisting of a continuous base of dendritic solidification—a matrix with an interdendritic region without other microstructural components and complex spheres. A model of the probable flow of metastable solidification of the studied alloy was proposed, based on the separation of L—melts into L1 (rich in Ni) and L2 (rich in Ag). The phenomenon of liquid phase separation in the considered CCNA is based on the monotectic reaction in the Ag−Ni system.
Properties of AgSnO2 Contact Materials Doped with Different Concentrations of Cr
Authors: Wang Jingqin , Xu Jingting , Zhu Yancai , Hu Delin , Lu Ningyi , Cui Defeng , Guo Peijian
Published: July 2022

As an important component carrying the core function and service life of switching appliances, the selection and improvement of electrical contact materials is of great significance. AgSnO2, which is non-toxic, environmentally friendly and has excellent performance, has become the most promising contact material to replace AgCdO. However, it has deficiencies in machinability and electrical conductivity. The property of AgSnO2 contact material was improved by doping element Cr. The relationship between the mechanical and electrical properties of AgSnO2 contact materials and doping concentrations were investigated and analyzed by simulation and experiment. Based on the first principle, the elastic constants of supercell models Sn1−xCrxO2 (x = 0, 0.083, 0.125, 0.167, 0.25) were calculated. The results show that the material with a doping ratio of 25% is least prone to warp and crack, and the material with a doping ratio of 12.5% has the best toughness and ductility and the lowest hardness, which leads to molding and is subsequently easier to process. The Cr-doped AgSnO2 contacts with different doping proportions were prepared by the sol–gel and powder metallurgy method. Additionally, their physical performance and electrical contact properties were measured in experiments. The results show that the doped SnO2 powders prepared by the sol–gel method realize integration doping, which is consistent with the crystal model constructed in the simulation calculation. Sn0.875Cr0.125O2 has lower hardness, which is beneficial to process and form. Doping helps to stabilize the arc root, inhibit the ablation of contact by arc, reduces arc duration and arc energy, improves the resistance to arc erosion of AgSnO2 contact material, and makes electrical contact performance more stable. The contact material with a doping concentration of 16.7% has the best arc erosion resistance.
Bending and Crack Evolution Behaviors of Cemented Soil Reinforced with Surface Modified PVA Fiber
Authors: Liang Lisheng , Xu Yaxing , Hu Shunlei
Published: July 2022

To improve the flexural properties of cemented soils reinforced with fibers and avoid their brittle failure when subjected to complex loading conditions, a simple and cost-effective technique was explored to facilitate their application in retaining walls. In this study, how different fiber surface modifications, i.e., alkali treatment, acid treatment and silane coupling agent treatment, as well as different fiber contents, i.e., 0%, 0.25%, 0.5% and 1%, affect the bending properties of cemented soils was investigated by conducting three-point bending tests on notched beams. The digital image correlation (DIC) technology was used to examine the crack propagation process and the strain field distribution of cracks in specimens in the flexural tests. The results show that all fiber surface modifications increased peak strength and fracture energy, for example, the fracture energy of specimens AN1, AH1 and AK1 was increased by 180.4%, 121.5% and 155.4%, respectively, compared to PVA1. In addition, the crack tip strain, crack propagation rate and the initial crack width of the modified specimens were lower than those before modification. Lastly, scanning electron microscope (SEM) and mercury intrusion porosimetry tests were adopted to reveal the mechanism of bending performance in cemented soils reinforced by fiber surface modifications.
Numerical Investigation of the Defects Effect in Additive Manufactured Ti-6Al-4V Struts on Deformation Behavior Based on Microtomographic Images
Authors: Doroszko Michał
Published: July 2022

This paper describes the influence of defects occurring in struts under tension, obtained using the additive method of laser powder bed fusion (LPBF), on the stress and strain distributions. The study used struts of different thicknesses separated from Ti-6Al-4V diamond lattice structures. For numerical modeling of stress and strain fields, models that reflect the realistic shape of the tested struts with their imperfections were used. The shape of the diamond structure struts was obtained based on microtomographic measurements. Based on the results obtained, the influence of defects in the material structure on the stress and strain distribution was analyzed. It was observed that the main factor influencing the stress and strain distribution in the struts are micronotches on their external surface. These imperfections have a significantly greater impact on the stress and strain concentration than the micropores inside. Furthermore, the interactions of the imperfections are also important, which in turn affects the stress distributions and the formation of bands of high-stress values inside the material. The relationship between the presence of micropores, the stress–strain curves, and the mechanical properties of the material was also assessed.
Use of Fluidized Bed Combustion Fly Ash as a Partial Substitute for Cement in Underwater Concrete Mixes
Authors: Horszczaruk Elżbieta , Seul Cyprian
Published: July 2022

Despite limitations to coal combustion energy production, many countries face the still-unresolved problem of utilising the wastes from fluidised bed coal combustion. One direction of rational utilisation can be using these wastes in the building materials industry. The study aimed to analyse the possibility of using fluidised bed combustion fly ashes as a partial substitute for cement in the underwater concrete (UWC). Two groups of concrete mixes were tested, containing 20 to 50% of fluidised bed combustion fly ashes. Investigations of the rheological properties of the concrete mixes and the mechanical performance of the hardened concrete confirmed the possibility of replacing cement in UWC with fluidised bed combustion fly ash up to 30% of the cement mass. The higher content of the fly ashes significantly worsens the UWC strength as well as the consistency and wash-out loss of the concrete mixes, excluding its use in underwater concreting.