bluuebunny/crossref_metadata_2025 huggingface dataset:
Dental Anxiety and Oral-Health-Related Quality of Life among Rural Community-Dwelling Older Adults
Authors: Hassan Bothaina Hussein , Abd El Moniem Maha Mohammed , Dawood Shaimaa Samir , Alsultan Abdulrahman Abdulhadi , Abdelhafez Amal Ismael , Elsakhy Nancy Mahmoud
Published: June 2022

Aim: This study aimed to investigate the association between dental anxiety (DA) and oral-health-related quality of life (OHRQoL) among rural community-dwelling older adults. Methods: A cross-sectional descriptive study was conducted among 390 rural community-dwelling older adults attending outpatient clinics of the Damanhur National Medical Institute during the year 2021. Three instruments were used: a demographic and clinical data structured interview schedule, Modified Dental Anxiety Scale (MDAS), and the Oral Health Impact Profile (OHIP-5) questionnaire. All statistical analyses were considered significant at a p-value of ≤0.001. Results: The main results showed that the prevalence of DA among participants was 90.5%, and 66.9% of the studied elderly population were either extremely (phobic) or very anxious. Moreover, a significant association was found between older adults’ DA and their OHRQoL (p ˂ 0.001). Conclusions: It was concluded that DA represents a common problem among rural community-dwelling older adults and is a predictor for poor OHRQoL. Raising community awareness about the importance of oral health and implementing measures to avoid DA through specialized community campaigns is recommended, particularly in rural areas.
Is a Pleasant Policy Environment Conducive to Green Growth of Central China?
Authors: Zhang Jianqing , Gong Enze , Tong Fangheng , Li Shuting
Published: June 2022

Improving the pleasantness of the policy environment in Central China stimulates economic growth, but it also contains higher risks of pollution. Based on the data of 80 cities in Central China from 2006 to 2018, the entropy method was used to estimate the pleasantness of policy environment in the region. How the policy environment has changed and whether the pleasant policy environment in the region is conducive to green growth were empirically studied. The results show the following: (1) The current attempts to improve the pleasantness of the policy environment in Central China is not conducive to green growth of the region. (2) Improving the pleasantness of the policy environment has indirect negative impacts on green growth through widening the development gap between prefecture-level cities and provincial capitals, as well as encouraging foreign trade; meanwhile, it also has an indirect positive impact through stimulating industrial diversification. The policy environment does not indirectly affect green growth through affecting technological innovation. (3) The policy environment in Central China will have a heterogeneous effect on the green growth of cities from the perspective of spatial heterogeneity and heterogeneity of city characteristics. In this paper, policy implications are proposed.
How Does Perceived Neighborhood Environment Affect Commuting Mode Choice and Commuting CO2 Emissions? An Empirical Study of Nanjing, China
Authors: Cao Chen , Zhen Feng , Huang Xianjin
Published: June 2022

Exploring the impacts of perceived neighborhood environment on commuting behavior and travel-related CO2 emissions helps policymakers formulate regional low-carbon transport policies. Most studies have examined the impact of the objective measures of built environment on travel behavior and related CO2 emissions, and few studies have focused on perceived neighborhood environment. This study develops a structural equation model and uses data from a self-administered survey of urban full-time employees in Nanjing, China to examine the direct and indirect effects of perceived neighborhood environment on commuting mode choice and commuting CO2 emissions. The study shows that perceived service facilities has a significant direct effect on commuting mode and a significant indirect effect on commuting CO2 through the mediating effect of commuting mode choice. While socio-demographic variables such as gender have a significant direct impact on commuting mode and commuting CO2 emissions, they have an indirect impact on commuting mode and commuting CO2 emissions through the intermediate variables (such as car ownership, perceived neighborhood environment and commuting distance). The conclusions of this study show that the potential of commuting CO2 emissions reduction in China is enormous, and that policy interventions on commuting would help developing countries such as China achieve the goals of low-carbon transport and sustainable development.
“Let’s Use This Mess to Our Advantage”: Calls to Action to Optimize School Nutrition Program beyond the Pandemic
Authors: Katz Beth N. , Soldavini Jessica , Grover Kiran , Jilcott Pitts Stephanie , Martin Stephanie L. , Thayer Linden , Ammerman Alice S. , Lane Hannah G.
Published: June 2022

School nutrition programs mitigate food insecurity and promote healthy eating by offering consistent, nutritious meals to school-aged children in communities across the United States; however, stringent policy guidelines and contextual challenges often limit participation. During COVID-19 school closures, most school nutrition programs remained operational, adapting quickly and innovating to maximize reach. This study describes semi-structured interviews with 23 nutrition directors in North Carolina, which aimed to identify multi-level contextual factors that influenced implementation, as well as ways in which the innovations during COVID-19 could translate to permanent policy and practice change and improve program reach. Interviews were conducted during initial school closures (May–August 2020) and were deductively analyzed using the Social Ecological Model (SEM) and Consolidated Framework for Implementation Research (CFIR). Analysis elicited multiple relevant contextual factors: director characteristics (motivation, leadership style, experience), key implementation stakeholders (internal staff and external partners), inner setting (implementation climate, local leadership engagement, available resources, structural characteristics), and outer setting (state leadership engagement, external policies and incentives). Findings confirm the strength and resilience of program directors and staff, the importance of developing strategies to strengthen external partnerships and emergency preparedness, and strong support from directors for policies offering free meals to all children.
18F-FDG PET/CT Did Not Increase the Risk of Cataract Occurrence in Oncology Patients: A Nationwide Population-Based Cohort Study
Authors: Cheng Kai-Lun , Huang Jing-Yang , Weng Jui-Hung , Chiou Jeng-Yuan , Lan Chyn-Tair , Tung Kwong-Chung
Published: June 2022

This study aimed to evaluate the risk of cataract formation associated with radiation exposure from 18F-FDG PET/CT in oncology patients, using data from Taiwan’s National Health Insurance Research Database. The exposed group (Group E) consisted of oncology patients receiving 18F-FDG PET/CT within the first year of a cancer diagnosis. The comparison group (Group C) included subjects who had never been exposed to 18F-FDG PET/CT radiation and were propensity score-matched by date of enrolment, age, sex, cancer type, associated comorbidities, and CT utilization. Multiple Cox proportional hazard regression analysis was used to estimate the hazard ratio (HR) of cataract risk due to radiation exposure, while adjusting for potential confounding factors. A total of 703 patients and 1406 matched subjects were in Groups E and C, respectively. The incidence of cataract formation was not significantly higher among subjects in Group E (adjusted HR = 1.264; 95% confidence interval [CI] = 0.845–1.891). Our results revealed that 18F-FDG PET/CT was not a significant risk factor for developing cataracts in oncology patients.
Oral Health and Frailty in Community-Dwelling Older Adults in the Northern Netherlands: A Cross-Sectional Study
Authors: Dros Coen , Sealy Martine J. , Krijnen Wim P. , Weening-Verbree Lina F. , Hobbelen Hans , Jager-Wittenaar Harriët
Published: June 2022

The aim of this study was to explore the association between oral health and frailty in community-dwelling Dutch adults aged 55 years and older. Included were 170 participants (n = 95 female [56%]; median age 64 years [IQR: 59–69 years]). Frailty was assessed by the Groningen Frailty Indicator. Oral health was assessed by the Oral Health Impact Profile-14-NL (OHIP-NL14). OHIP-NL14 item scores were analyzed for differences between frail and non-frail participants. Univariate and multivariate logistic regression analyses were performed to assess the association between oral health and presence of frailty. The multivariate analysis included age, gender, and depressive symptoms as co-variables. After adjustment, 1 point increase on the OHIP-NL14 scale was associated with 21% higher odds of being frail (p = 0.000). In addition, significantly more frail participants reported presence of problems on each OHIP-NL14 item, compared to non-frail participants (p < 0.003). Contrast in prevalence of different oral health problems between frail and non-frail was most prominent in ‘younger’ older adults aged 55–64 years. In conclusion: decreased oral health was associated with frailty in older adults aged ≥55 years. Since oral health problems are not included in most frailty assessments, tackling oral health problems may not be sufficiently emphasized in frailty policies.
The Rationale for Using Neridronate in Musculoskeletal Disorders: From Metabolic Bone Diseases to Musculoskeletal Pain
Authors: Iolascon Giovanni , Moretti Antimo
Published: June 2022

Neridronate or ((6-amino-1-hydroxy-1-phosphonohexyl) phosphonic acid) is an amino-bisphosphonate (BP) synthetized in Italy in 1986. Bisphosphonates are molecules with a P-C-P bond in their structure that allows strong and selectively binding to hydroxyapatite (HAP) as well as osteoclasts inhibition through different mechanisms of action. Neridronate was initially used to treat Paget disease of the bone, demonstrating effectiveness in reducing bone turnover markers as well as pain. The interesting molecular properties of neridronate foster its wide use in several other conditions, such as osteogenesis imperfecta, and osteoporosis. Thanks to the unique safety and efficacy profile, neridronate has been used in secondary osteoporosis due to genetic, rheumatic, and oncological diseases, including in pediatric patients. In the last decade, this drug has also been studied in chronic musculoskeletal pain conditions, such as algodystrophy, demonstrating effectiveness in improving extraskeletal outcomes. This review highlights historical and clinical insights about the use of neridronate for metabolic bone disorders and musculoskeletal pain conditions.
Specific Cerebrospinal Fluid SerpinA1 Isoform Pattern in Alzheimer’s Disease
Authors: Barba Lorenzo , Halbgebauer Steffen , Paolini Paoletti Federico , Bellomo Giovanni , Abu-Rumeileh Samir , Steinacker Petra , Massa Federico , Parnetti Lucilla , Otto Markus
Published: June 2022

SerpinA1 (α1-antitrypsin) is a soluble glycoprotein, the cerebrospinal fluid (CSF) isoforms of which showed disease-specific changes in neurodegenerative disorders that are still unexplored in Alz-heimer’s disease (AD). By means of capillary isoelectric focusing immunoassay, we investigated six serpinA1 isoforms in CSF samples of controls (n = 29), AD-MCI (n = 29), AD-dem (n = 26) and Lewy body disease (LBD, n = 59) patients and correlated the findings with CSF AD core biomarkers (Aβ42/40 ratio, p-tau, t-tau). Four CSF serpinA1 isoforms were differently expressed in AD patients compared to controls and LBD patients, especially isoforms 2 and 4. AD-specific changes were found since the MCI stage and significantly correlated with decreased Aβ42/40 (p < 0.05) and in-creased p-tau and t-tau levels in CSF (p < 0.001). Analysis of serpinA1 isoform provided good di-agnostic accuracy in discriminating AD patients versus controls (AUC = 0.80) and versus LBD patients (AUC = 0.92), with best results in patients in the dementia stage (AUC = 0.97). SerpinA1 isoform expression is altered in AD patients, suggesting a common, albeit disease-specific, in-volvement of serpinA1 in most neurodegenerative disorders.
Therapeutic Effect of Mitochondrial Division Inhibitor-1 (Mdivi-1) on Hyperglycemia-Exacerbated Early and Delayed Brain Injuries after Experimental Subarachnoid Hemorrhage
Authors: Chung Chia-Li , Huang Yu-Hua , Lin Chien-Ju , Chong Yoon-Bin , Wu Shu-Chuan , Chai Chee-Yin , Tsai Hung-Pei , Kwan Aij-Lie
Published: June 2022

Background: Neurological deficits following subarachnoid hemorrhage (SAH) are caused by early or delayed brain injuries. Our previous studies have demonstrated that hyperglycemia induces profound neuronal apoptosis of the cerebral cortex. Morphologically, we found that hyperglycemia exacerbated late vasospasm following SAH. Thus, our previous studies strongly suggest that post-SAH hyperglycemia is not only a response to primary insult, but also an aggravating factor for brain injuries. In addition, mitochondrial fusion and fission are vital to maintaining cellular functions. Current evidence also shows that the suppression of mitochondrial fission alleviates brain injuries after experimental SAH. Hence, this study aimed to determine the effects of mitochondrial dynamic modulation in hyperglycemia-related worse SAH neurological prognosis. Materials and methods: In vitro, we employed an enzyme-linked immunosorbent assay (ELISA) to detect the effect of mitochondrial division inhibitor-1 (Mdivi-1) on lipopolysaccharide (LPS)-induced BV-2 cells releasing inflammatory factors. In vivo, we produced hyperglycemic rats via intraperitoneal streptozotocin (STZ) injections. Hyperglycemia was confirmed using blood-glucose measurements (>300 mg/dL) 7 days after the STZ injection. The rodent model of SAH, in which fresh blood was instilled into the craniocervical junction, was used 7 days after STZ administration. We investigated the mechanism and effect of Mdivi-1, a selective inhibitor of dynamin-related protein (Drp1) to downregulate mitochondrial fission, on SAH-induced apoptosis in a hyperglycemic state, and evaluated the results in a dose–response manner. The rats were divided into the following five groups: (1) control, (2) SAH only, (3) Diabetes mellitus (DM) + SAH, (4) Mdivi-1 (0.24 mg/kg) + DM + SAH, and (5) Mdivi-1 (1.2 mg/kg) + DM + SAH. Results: In vitro, ELISA revealed that Mdivi-1 inhibited microglia from releasing inflammatory factors, such as tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, and IL-6. In vivo, neurological outcomes in the high-dose (1.2 mg/kg) Mdivi-1 treatment group were significantly reduced compared with the SAH and DM + SAH groups. Furthermore, immunofluorescence staining and ELISA revealed that a high dose of Mdivi-1 had attenuated inflammation and neuron cell apoptosis by inhibiting Hyperglycemia-aggravated activation, as well as microglia and astrocyte proliferation, following SAH. Conclusion: Mdivi-1, a Drp-1 inhibitor, attenuates cerebral vasospasm, poor neurological outcomes, inflammation, and neuron cell apoptosis following SAH + hyperglycemia.
Degradation by Electron Beam Irradiation of Some Composites Based on Natural Rubber Reinforced with Mineral and Organic Fillers
Authors: Manaila Elena , Craciun Gabriela , Ighigeanu Daniel , Lungu Ion Bogdan , Dumitru Grivei Marius Daniel , Stelescu Maria Daniela
Published: June 2022

Composites based on natural rubber reinforced with mineral (precipitated silica and chalk) and organic (sawdust and hemp) fillers in amount of 50 phr were obtained by peroxide cross-linking in the presence of trimethylolpropane trimethacrylate and irradiated by electron beam in the dose range of 150 and 450 kGy with the purpose of degradation. The composites mechanical characteristics, gel fraction, cross-linking degree, water uptake and weight loss in water and toluene were evaluated by specific analysis. The changes in structure and morphology were also studied by Fourier Transform Infrared Spectroscopy and Scanning Electron Microscopy. Based on the results obtained in the structural analysis, possible mechanisms specific to degradation are proposed. The increasing of irradiation dose to 450 kGy produced larger agglomerated structures, cracks and micro voids on the surface, as a result of the degradation process. This is consistent with that the increasing of irradiation dose to 450 kGy leads to a decrease in crosslinking and gel fraction but also drastic changes in mechanical properties specific to the composites’ degradation processes. The irradiation of composites reinforced with organic fillers lead to the formation of specific degradation compounds of both natural rubber and cellulose (aldehydes, ketones, carboxylic acids, compounds with small macromolecules). In the case of the composites reinforced with mineral fillers the degradation can occur by the cleavage of hydrogen bonds formed between precipitated silica or chalk particles and polymeric matrix also.
Novel Drugs with High Efficacy against Tumor Angiogenesis
Authors: Qi Shiyu , Deng Shoulong , Lian Zhengxing , Yu Kun
Published: June 2022

Angiogenesis is involved in physiological and pathological processes in the body. Tumor angiogenesis is a key factor associated with tumor growth, progression, and metastasis. Therefore, there is great interest in developing antiangiogenic strategies. Hypoxia is the basic initiating factor of tumor angiogenesis, which leads to the increase of vascular endothelial growth factor (VEGF), angiopoietin (Ang), hypoxia-inducible factor (HIF-1), etc. in hypoxic cells. The pathways of VEGF and Ang are considered to be critical steps in tumor angiogenesis. A number of antiangiogenic drugs targeting VEGF/VEGFR (VEGF receptor) or ANG/Tie2, or both, are currently being used for cancer treatment, or are still in various stages of clinical development or preclinical evaluation. This article aims to review the mechanisms of angiogenesis and tumor angiogenesis and to focus on new drugs and strategies for the treatment of antiangiogenesis. However, antitumor angiogenic drugs alone may not be sufficient to eradicate tumors. The molecular chaperone heat shock protein 90 (HSP90) is considered a promising molecular target. The VEGFR system and its downstream signaling molecules depend on the function of HSP90. This article also briefly introduces the role of HSP90 in angiogenesis and some HSP90 inhibitors.
Seventy-Two-Hour LRRK2 Kinase Activity Inhibition Increases Lysosomal GBA Expression in H4, a Human Neuroglioma Cell Line
Authors: Ruz Clara , Alcantud José Luis , Vives Francisco , Arrebola Francisco , Hardy John , Lewis Patrick A. , Manzoni Claudia , Duran Raquel
Published: June 2022

Mutations in LRRK2 and GBA1 are key contributors to genetic risk of developing Parkinson’s disease (PD). To investigate how LRRK2 kinase activity interacts with GBA and contributes to lysosomal dysfunctions associated with the pathology of PD. The activity of the lysosomal enzyme β-Glucocerebrosidase (GCase) was assessed in a human neuroglioma cell model treated with two selective inhibitors of LRKK2 kinase activity (LRRK2-in-1 and MLi-2) and a GCase irreversible inhibitor, condutirol-beta-epoxide (CBE), under 24 and 72 h experimental conditions. We observed levels of GCase activity comparable to controls in response to 24 and 72 h treatments with LRRK2-in-1 and MLi-2. However, GBA protein levels increased upon 72 h treatment with LRRK2-in-1. Moreover, LC3-II protein levels were increased after both 24 and 72 h treatments with LRRK2-in-1, suggesting an activation of the autophagic pathway. These results highlight a possible regulation of lysosomal function through the LRRK2 kinase domain and suggest an interplay between LRRK2 kinase activity and GBA. Although further investigations are needed, the enhancement of GCase activity might restore the defective protein metabolism seen in PD.
Early Life Stage Folic Acid Deficiency Delays the Neurobehavioral Development and Cognitive Function of Rat Offspring by Hindering De Novo Telomere Synthesis
Authors: Zhou Dezheng , Li Zhenshu , Sun Yue , Yan Jing , Huang Guowei , Li Wen
Published: June 2022

Early life stage folate status may influence neurodevelopment in offspring. The developmental origin of health and disease highlights the importance of the period of the first 1000 days (from conception to 2 years) of life. This study aimed to evaluate the effect of early life stage folic acid deficiency on de novo telomere synthesis, neurobehavioral development, and the cognitive function of offspring rats. The rats were divided into three diet treatment groups: folate-deficient, folate-normal, and folate-supplemented. They were fed the corresponding diet from 5 weeks of age to the end of the lactation period. After weaning, the offspring rats were still fed with the corresponding diet for up to 100 days. Neurobehavioral tests, folic acid and homocysteine (Hcy) levels, relative telomere length in brain tissue, and uracil incorporation in telomere in offspring were measured at different time points. The results showed that folic acid deficiency decreased the level of folic acid, increased the level of Hcy of brain tissue in offspring, increased the wrong incorporation of uracil into telomeres, and hindered de novo telomere synthesis. However, folic acid supplementation increased the level of folic acid, reduced the level of Hcy of brain tissue in offspring, reduced the wrong incorporation of uracil into telomeres, and protected de novo telomere synthesis of offspring, which was beneficial to the development of early sensory-motor function, spatial learning, and memory in adolescence and adulthood. In conclusion, early life stage folic acid deficiency had long-term inhibiting effects on neurodevelopment and cognitive function in offspring.
Role of Impaired Mitochondrial Dynamics Processes in the Pathogenesis of Alzheimer’s Disease
Authors: Blagov Alexander V. , Grechko Andrey V. , Nikiforov Nikita G. , Borisov Evgeny E. , Sadykhov Nikolay K. , Orekhov Alexander N.
Published: June 2022

Mitochondrial dysfunction is now recognized as a contributing factor to neurodegenerative diseases, including Alzheimer’s disease (AD). Mitochondria are signaling organelles with a variety of functions ranging from energy production to the regulation of cellular metabolism, energy homeostasis, and response to stress. The successful functioning of these complex processes is critically dependent on the accuracy of mitochondrial dynamics, which includes the ability of mitochondria to change shape and position in the cell, which is necessary to maintain proper function and quality control, especially in polarized cells such as neurons. There has been much evidence to suggest that the disruption of mitochondrial dynamics may play a critical role in the pathogenesis of AD. This review highlights aspects of altered mitochondrial dynamics in AD that may contribute to the etiology of this debilitating condition. We also discuss therapeutic strategies to improve mitochondrial dynamics and function that may provide an alternative treatment approach.
Enhanced Photocatalytic Degradation of Rhodamine-B under Led Light Using CuZnAl Hydrotalcite Synthesized by Co-Precipitation Technique
Authors: Vu Van Nhuong , Pham Thi Ha Thanh , Chanthavong Maiboun , Do Tra Huong , Nguyen Thi Hien Lan , Nguyen Quoc Dung , Tran Thi Kim Ngan
Published: June 2022

The co-precipitation method was employed to synthesize a set of ZnAl hydrotalcite materials modified by Cu2+. The synthesized materials have a similar lamellar structure to that of hydrotalcite. The distance between layers is in the range of 7.73–8.56 Å. The network parameters a and c ranged from 3.058 to 3.074 Å and from 23.01 to 24.44, respectively. According to the IUPAC classification, the composites possess a mesoporous structure which belongs to class IV, type H 3. Particularly, the absorption edge shifts strongly to the visible light region when increasing the molar ratio of Cu2+ in the samples from 0 to 3.5. The photocatalytic activity of the synthetic materials was evaluated through the degradation efficiency of rhodamine-B (Rh-B) in the water and colorants in textile wastewater. The present study was the first to synthesize a material sample that contains a molar ratio of Cu2+ in the range of 2.5–3.5 and has high catalytic activities. They were able to degrade Rh-B at a high concentration (100 ppm) with a conversion rate of approximately 90% after 240 min of irradiation using a 30 W LED light. The catalytic activity of the composites depends on the molar ratio of modified Cu2+, the value of environmental pH, the H2O2 concentration and the irradiation time.
Mobile Visual Servoing Based Control of a Complex Autonomous System Assisting a Manufacturing Technology on a Mechatronics Line
Authors: Simion Georgian , Filipescu Adrian , Ionescu Dan , Șolea Răzvan , Cernega Daniela , Mincă Eugenia , Filipescu Adriana
Published: June 2022

The main contribution of this paper is the modeling and control for a complex autonomous system (CAS). It is equipped with a visual sensor to operate precision positioning in a technology executed on a laboratory mechatronics line. The technology allows the retrieval of workpieces which do not completely pass the quality test. Another objective of this paper is the implementation of an assisting technology for a laboratory processing/reprocessing mechatronics line (P/RML) containing four workstations, assisted by the following components: a complex autonomous system that consists of an autonomous robotic system (ARS), a wheeled mobile robot (WMR) PeopleBot, a robotic manipulator (RM) Cyton 1500 with seven degrees of freedom (7 DOF), and a mobile visual servoing system (MVS) with a Logitech camera as visual sensor used in the process of picking, transporting and placing the workpieces. The purpose of the MVS is to increase the precision of the RM by utilizing the look and move principle, since the initial and final positions of the CAS can slightly deviate from their trajectory, thus increasing the possibility of errors to appear during the process of catching and releasing the pieces. If the processed piece did not pass the quality test and has been rendered as defective, it is retrieved from the last station of the P/RML and transported to the first station for reprocessing. The control of the WMR is done using the trajectory-tracking sliding-mode control (TTSMC). The RM control is based on inverse kinematics model, and the MVS control is implemented with the image moments method.
A Review of Rubber Biocomposites Reinforced with Lignocellulosic Fillers
Authors: Kazemi Hossein , Mighri Frej , Rodrigue Denis
Published: June 2022

Lignocellulosic fillers have attracted considerable attention over the years as a promising alternative to conventional petroleum-based fillers (carbon black) in rubber composites due to their renewability, biodegradability, availability, high mechanical properties, low density and low cost. Based on the literature available, a comprehensive review is presented here of rubber biocomposites reinforced with plant-based fillers. The study is divided into different sections depending on the matrix (natural or synthetic rubber) and the type of lignocellulosic fillers (natural fiber, microcrystalline cellulose, lignin and nanocellulose). This review focuses on the curing characteristics, mechanical properties and dynamic mechanical properties of the resulting rubber biocomposites. In addition, the effect of hybrid filler systems, lignocellulosic filler surface modification and modification of the rubber matrix on the properties of these rubber biocomposites are presented and compared. A conclusion is finally presented with some openings for future works.
Intra-Species Genomic Variation in the Pine Pathogen Fusarium circinatum
Authors: Maphosa Mkhululi N. , Steenkamp Emma T. , Kanzi Aquillah M. , van Wyk Stephanie , De Vos Lieschen , Santana Quentin C. , Duong Tuan A. , Wingfield Brenda D.
Published: June 2022

Fusarium circinatum is an important global pathogen of pine trees. Genome plasticity has been observed in different isolates of the fungus, but no genome comparisons are available. To address this gap, we sequenced and assembled to chromosome level five isolates of F. circinatum. These genomes were analysed together with previously published genomes of F. circinatum isolates, FSP34 and KS17. Multi-sample variant calling identified a total of 461,683 micro variants (SNPs and small indels) and a total of 1828 macro structural variants of which 1717 were copy number variants and 111 were inversions. The variant density was higher on the sub-telomeric regions of chromosomes. Variant annotation revealed that genes involved in transcription, transport, metabolism and transmembrane proteins were overrepresented in gene sets that were affected by high impact variants. A core genome representing genomic elements that were conserved in all the isolates and a non-redundant pangenome representing all genomic elements is presented. Whole genome alignments showed that an average of 93% of the genomic elements were present in all isolates. The results of this study reveal that some genomic elements are not conserved within the isolates and some variants are high impact. The described genome-scale variations will help to inform novel disease management strategies against the pathogen.
The Dynamic Nature of Human Dermal Fibroblasts Is Defined by Marked Variation in the Gene Expression of Specific Cytoskeletal Markers
Authors: Ahuja Akshay Kumar , Pontiggia Luca , Moehrlen Ueli , Biedermann Thomas
Published: June 2022

The evidence for fibroblast heterogeneity is continuously increasing, and recent work has shed some light on the existence of different sub-populations of fibroblasts in the human skin. Although we now have a more precise understanding of their distribution in the human body, we do not know whether their properties are predictive of where these cells derive from or whether these sub-types have functional consequences. In this study, we employed single-cell transcriptomics (10X Genomics) to study gene expression and segregate fibroblast sub-populations based on their genetic signature. We report the differential expression of a defined set of genes in fibroblasts from human skin, which may contribute to their dynamicity in vivo and in vitro. We show that the sub-population of fibroblasts expressing cytoskeletal markers, such as ANXA2, VIM, ACTB, are enriched in an adult skin sample. Interestingly, this sub-population of fibroblasts is not enriched in a neonatal skin sample but becomes predominant when neonatal fibroblasts are cultivated. On the other hand, the fibroblast sub-populations expressing COL1A1 and ELN are enriched in neonatal skin but are reduced in the adult skin and in fibroblasts from neonatal skin that are cultured in vitro. Our results indicate that fibroblasts are a dynamic cell type, and while their genetic make-up changes markedly, only a handful of genes belonging to the same functional pathway govern this alteration. The gene expression pattern of cytoskeletal markers may help in identifying whether the fibroblasts were isolated from an adult or an infant or whether they were cultivated, and this information could be useful for quality control in clinics and in cell banking. Furthermore, this study opens additional avenues to investigate the role of these markers in defining the complexity of human dermal fibroblasts.
Investigation of the Ligand Exchange Process on Gold Nanorods by Using Laser Desorption/Ionization Time-of-Flight Mass Spectrometry
Authors: Kim Seung-Woo , Kim Young Won , Seo Tae Hoon , Kim Young-Kwan
Published: June 2022

The ligand exchange process on gold nanorods (Au NRs) was explored by using laser desorption/ionization time-of-flight mass spectrometry (LDI-TOF-MS). Cetyltrimethylammonium bromide (CTAB) adsorbed on Au NRs was replaced with alkanethiol derivatives presenting different functional groups. The ligand exchange process was investigated under various conditions, such as in the presence of different functional groups in the ligands and with different concentrations of CTAB. The ligand-exchanged Au NRs were characterized by using a combination of UV–Vis spectroscopy and LDI-TOF-MS. Based on the results, it was revealed that LDI-TOF-MS analysis can provide crucial and distinct information about the degree of ligand exchange on Au NRs.
Size-Dependent Persistent Luminescence of YAGG:Cr3+ Nanophosphors
Authors: Boiko Vitalii , Dai Zhengfa , Chaika Mykhailo , Grzeszkiewicz Karina , Li Jiang , Strek Wieslaw , Hreniak Dariusz
Published: June 2022

In the current work, YAGG:Cr3+ nanophosphors were synthesized by the Pechini method and then annealed at different temperatures in the range 800–1300 °C. The structure and morphology of the samples were characterized by X-ray Powder Diffraction (XRPD). The lattice parameters and average crystalline sizes as site occupation by Al3+ and Ga3+ ions were calculated from the Rietveld refinement data. To investigate the effect of crystalline size of the materials on their optical properties: excitation and emission spectra were recorded and analyzed. Finally, the effect of crystalline size on the probability of carrier recombination leading to PersL was determined experimentally with thermoluminescence analyses. The Tmax-Tstop method was applied to determine the trap type and particle size (calcination temperature) effect on their redistribution. A correlation between structural changes and trap redistribution was found. In particular, the extinction of high-temperature TL maximum with increasing annealing temperatures is observed, while low-temperature TL maximum increases and reaches a maximum when the lattice parameter reaches saturation.
Characterizing the Phase-Structure and Rheological Response-Behavior of Multi-Walled Carbon Nanotubes Modified Asphalt-Binder
Authors: Li Yongyi , Zhang Weijie , Yin Chaoen , Zhang Xiaorui
Published: June 2022

In this study, the phase-structure and rheological response-behavior of multi-walled carbon nanotube (MWCNTs) modified asphalt-binder (MWCNTs-MA) were measured and quantified in the laboratory. The changes in the molecular dynamics due to MWCNTs modification were simulated and quantified based on the intermolecular interaction energy computations, electrostatic potential surface analyses and phase-structure modeling of the asphalt-binder matrix. The rheological properties such as the asphalt-binder viscosity and complex modulus, of both the base and modified asphalt-binders, were determined using the standard Brookfield viscometer (BV) and dynamic shear rheology (DSR) test devices, respectively. In comparison to the base asphalt-binder, the corresponding BV-DSR test results exhibited higher viscosity and complex modulus for the MWCNTs modified asphalt-binder, with reduced sensitivity and susceptibility to temperature variations. From the study results, it was observed that MWCNTs significantly improved the rheological properties and high-temperature performance of the asphalt-binder. Overall, the study has demonstrated that MWCNT modified asphalt-binder has great promising potential for application and usage as a road-pavement material, particularly with respect to mitigating the high temperature related distresses such as rutting.
Study on Ultrasonic Nondestructive Testing of Self-Compacting Concrete under Uniaxial Compression Test
Authors: Sun Yongshuai , Wang Guihe , Li Yixuan
Published: June 2022

To study the variation law of ultrasonic parameters of self-compacting concrete before and after damage under uniaxial compression test conditions, the C30 self-compacting concrete blocks stored for 7 days and 28 days were subjected to ultrasonic nondestructive testing, and the variation law of the sound time, amplitude, and sound velocity before and after the damage of self-compacting concrete blocks was emphatically analyzed. The concrete acoustic detection software was introduced to judge and analyze the abnormal values of the parameters of each measuring point, and the defect distribution map of each test block was obtained. The results showed that after curing the self-compacting concrete test block for 7 days and 28 days, the average value of sound time before and after the failure of each measuring point of the test block is small, and the average value of sound time before the failure is less than that after; the average amplitude after failure is smaller than that before failure, and the amplitude of some measuring points will be smaller than that before. The average sound velocity after failure is less than that before failure, and the internal defects appear and the structure is not dense. This study provides a theoretical basis for the application of ultrasonic detection technology in the field of self-compacting concrete and also provides a practical basis for the stability monitoring and failure warning of self-compacting concrete.
Experiment and Theoretical Investigation on Fatigue Life Prediction of Fracturing Pumpheads Based on a Novel Stress-Field Intensity Approach
Authors: Zeng Yun , Li Meiqiu , Wu Han , Li Ning , Zhou Yang
Published: June 2022

Fracturing pumpheads are typical pressure vessels that experience frequent fatigue failure under the effect of notches in their cross-bore. To enhance the fatigue life of fracturing pumpheads, the study of the notch effect is indispensable and important to establish a reliable mathematical model to predict their fatigue life. In the present paper, two novel fatigue life prediction models are proposed for notched specimens. In these models, two new geometric fatigue failure regions are defined to improve the weight function. Finally, the elaborated novel stress-field intensity approach was applied to three different types of notched specimens. Experiment results indicate that the new SFI approach achieves 47.82%, 39.48%, and 31.85% higher prediction accuracy than the traditional SFI approach, respectively. It was found that the modified SFI approach provided better predictions than the traditional SFI approach and the TCD method. The II-th novel SFI approach had the highest accuracy, and the I-th novel SFI approach was more suitable for sharply notched specimens.
An Improved U-Net Image Segmentation Method and Its Application for Metallic Grain Size Statistics
Authors: Shi Peng , Duan Mengmeng , Yang Lifang , Feng Wei , Ding Lianhong , Jiang Liwu
Published: June 2022

Grain size is one of the most important parameters for metallographic microstructure analysis, which can partly determine the material performance. The measurement of grain size is based on accurate image segmentation methods, which include traditional image processing methods and emerging machine-learning-based methods. Unfortunately, traditional image processing methods can hardly segment grains correctly from metallographic images with low contrast and blurry boundaries. Moreover, the proposed machine-learning-based methods need a large dataset to train the model and can hardly deal with the segmentation challenge of complex images with fuzzy boundaries and complex structure. In this paper, an improved U-Net model is proposed to automatically accomplish image segmentation of complex metallographic images with only a small training set. The experiments on metallographic images show the significant advantage of the method, especially for the metallographic images with low contrast, a fuzzy boundary and complex structure. Compared with other deep learning methods, the improved U-Net scored higher in ACC, MIoU, Precision, and F1 indexes, among which ACC was 0.97, MIoU was 0.752, Precision was 0.98, and F1 was 0.96. The grain size was calculated based on the segmentation according to the American Society for Testing Material (ASTM) standards, producing a satisfactory result.
Large Vertical Piezoelectricity in a Janus Cr2I3F3 Monolayer
Authors: Niu Haibo , Liu Yachao , Shi Jing , Wang Vei
Published: June 2022

Two-dimensional (2D) materials have potential applications in nanoscale sensors and spintronic devices. Herein, motivated by experimental synthesis of a CrI3 monolayer possessing intrinsic magnetism and a Janus MoSSe monolayer with piezoelectricity, we propose a 2D Janus Cr2I3F3 monolayer as a multifunctional material exhibiting both piezoelectricity and ferromagnetism. Using density functional theory calculations, we systematically investigated the structural stability and the electronic, magnetic, and piezoelectric properties of the Janus Cr2I3F3 monolayer. We predicted that a vertical polarization of up to −0.155 × 10−10 C/m is induced in the Cr2I3F3 monolayer due to the breaking of symmetry. The origination mechanism of polarization was demonstrated in terms of a local dipole moment calculated by maximally localized Wannier functions. Meanwhile, it was found that a remarkable piezoelectric response can be produced under a uniaxial strain in the basal plane. The calculated piezoelectric coefficients of the Cr2I3F3 monolayer compare favorably with those of the frequently used bulk piezoelectric materials such as α–quartz and wurtzite AlN. Particularly, the e31 and d31 values of the Cr2I3F3 monolayer are nearly 10 times as large as that of Mo-based transition metal dichalcogenides. We also found that the magnitude of e31 mainly arises from the ionic contribution, while the electronic contribution can be nearly neglected. The considerable piezoelectric response combined with the intrinsic magnetism make the Janus Cr2I3F3 monolayer a potential candidate for novel multifunctional devices integrating both piezoelectric and spintronic applications.
Finite Element Analysis of Steel Plates with Rectangular Openings Subjected to Axial Stress
Authors: Al-Yacouby Ahmad Mahamad , Mazli Arwie Amri , Liew M. S. , Ratnayake R. M. Chandima , Samarakoon Samindi M. K.
Published: June 2022

Steel plates with openings are among the important ship structural components used in the ship’s hull to withstand the hydrostatic forces of the ocean, which cause sagging and hogging moments at the ship’s bottom. The existence of openings on plates can cause structural rupture, stress concentration and a decrease in ultimate strength. This research is aimed at investigating the influence of selected parameters on the ultimate capacity of steel plates with rectangular holes subjected to axial stress, using ANSYS finite element analysis (FEA) under its non-linear static structural programme. The main parameters investigated in this paper are the plate thickness, opening aspect ratio, number of openings, position of openings, and the boundary condition of the plate. The influence of these parameters on the stress of plates and their deformation was evaluated. The comparison of the numerical simulation with the well-established analytical method using the Navier solution and Roark’s Formulas showed a good agreement.
Topology Optimization of Piezoelectric Energy Harvesters for Enhanced Open-Circuit Voltage Subjected to Harmonic Excitations
Authors: He Meng , He Mu , Zhang Xiaopeng , Xia Liang
Published: June 2022

Energy harvesting devices made of piezoelectric material are highly anticipated energy sources for power wireless sensors. Tremendous efforts have been made to improve the performance of piezoelectric energy harvesters (PEHs). Noticeably, topology optimization has shown an attractive potential to design PEHs with enhanced energy conversion efficiency. In this work, an alternative yet more practical design objective was considered, where the open-circuit voltage of PEHs is enhanced by topologically optimizing the through-thickness piezoelectric material distribution of plate-type PEHs subjected to harmonic excitations. Compared to the conventional efficiency-enhanced designs, the open-circuit voltage of PEHs can be evidently enhanced by the proposed method while with negligible sacrifice on the energy conversion efficiency. Numerical investigations show that the voltage cancellation effect due to inconsistent voltage phases can be effectively ameliorated by optimally distributed piezoelectric materials.
Partially Compacted Commingled PLA-Flax Biocomposites
Authors: Lekube Blanca Maria , Burgstaller Christoph
Published: June 2022

Non-woven materials feature unique properties that allow them to be used in different applications, such as the automotive sector that is increasingly seeking lightweight and sustainable materials. The aim of this work was to investigate the influence of reinforcement type and porosity on the properties of commingled, partially compacted composites based on polypropylene (PP) and polylactic acid (PLA). Furthermore, a model was applied to predict the properties of such composites, i.e., the elastic modulus, to aid materials development. It was found that high properties could be achieved using flax as reinforcement for partially compacted fleece biocomposites. Porosity is an important factor influencing these types of composites and was influenced by the compaction grade achieved as a result of stacking different numbers of layers during the consolidation of the composites. The modeling of the elastic modulus was found to be adequate for both PP-flax and PLA-flax composites for porosities under 20 vol.%.
Certifiable Unlearning Pipelines for Logistic Regression: An Experimental Study
Authors: Mahadevan Ananth , Mathioudakis Michael
Published: June 2022

Machine unlearning is the task of updating machine learning (ML) models after a subset of the training data they were trained on is deleted. Methods for the task are desired to combine effectiveness and efficiency (i.e., they should effectively “unlearn” deleted data, but in a way that does not require excessive computational effort (e.g., a full retraining) for a small amount of deletions). Such a combination is typically achieved by tolerating some amount of approximation in the unlearning. In addition, laws and regulations in the spirit of “the right to be forgotten” have given rise to requirements for certifiability (i.e., the ability to demonstrate that the deleted data has indeed been unlearned by the ML model). In this paper, we present an experimental study of the three state-of-the-art approximate unlearning methods for logistic regression and demonstrate the trade-offs between efficiency, effectiveness and certifiability offered by each method. In implementing this study, we extend some of the existing works and describe a common unlearning pipeline to compare and evaluate the unlearning methods on six real-world datasets and a variety of settings. We provide insights into the effect of the quantity and distribution of the deleted data on ML models and the performance of each unlearning method in different settings. We also propose a practical online strategy to determine when the accumulated error from approximate unlearning is large enough to warrant a full retraining of the ML model.