bluuebunny/crossref_metadata_2025 huggingface dataset:
Reliability of Smart Phone Photographs for School Eye Screening
Authors: Srivastava Rajat M. , Verma Suchi , Gupta Shubham , Kaur Apjit , Awasthi Shally , Agrawal Siddharth
Published: October 2022

Smartphone photographs capturing Bruckner’s reflex have demonstrated reliability in identifying amblyogenic conditions in children. Assessing visual acuity for screening has been the traditional method since the inception of school screening. The present study aims to assess the reliability of smartphone photographs in detecting ocular morbidities in school children and to compare it with traditional vision screening. Two thousand five hundred and twenty school children underwent vision screening and smartphone cameraphotography by a trained research assistant followed by a comprehensive eye examination of all children by an ophthalmologist. Children with unaided visual acuity less than 6/12 in either of the eyes were graded as abnormal. Based upon the characteristics of the Bruckner’s reflex, the photographs were graded as normal or abnormal by two investigators blinded to the clinical findings. Statistical analysis was performed to compare the sensitivity and specificity of traditional vision screening and photograph based screening, considering comprehensive eye examination as the gold standard. The sensitivity and specificity of vision screening was 81.88% and 97.35% whereas for photographs it was 94.69% and 98.85% respectively. When the two methods were compared, the p value was <0.05. We conclude that smartphone photography is better than traditional vision screening for detecting ocular morbidities in school children.
Food Insecurity in the Informal Settlements of Inanda Households Living with Children under 60 Months in Ethekwini Municipality
Authors: Mkhize Mbalenhle , Sibanda Melusi
Published: October 2022

Food insecurity is a continuing challenge for many households in South Africa. This challenge poses serious immediate and long-term health and development risks for children. Despite the intensive literature on household food insecurity, there is limited literature on the household food security status in South African informal settlements. Thus, the household food security status and dynamics in informal settlements are not clearly defined. Hence, this study assessed the food security status of households living with children under 60 months in the informal settlements of the Inanda area, eThekwini Municipality. This study employed a cross-sectional quantitative research approach. A non-probability sampling method was used, which used convenience sampling supplemented by a non-discriminative snowball sampling to obtain a sample size of 160 households with children under the age of five. Data was collected through face-to-face interviews, where questionnaires were administered to household child caregivers. Ethical considerations such as informed consent, anonymity, confidentiality, permission from authorities, and cultural considerations were obeyed in this study. The HFIAS and HDDS tools were used to estimate the household food security status. Data were coded and analysed in SPSS version 25 software. This study revealed that higher proportions of the surveyed informal households living with children under 60 months were food insecure. The HFIAS analysis showed that approximately 34, 31, and 28% were severely, mildly, and moderately food insecure, respectively. In contrast, a small (approximately 8%) proportion of the surveyed informal households was estimated to be food secure. The HDDS analysis revealed that most (approximately 77%) of the surveyed informal households had low dietary diversity (deemed food insecure). Cereal, roots, and fatty foods were the main dietary components in the informal settlements of Inanda. It is paramount to improve the food security status of informal households living with children under 60 months through an integrated approach. This study suggests government and private stakeholders’ engagement in developing policies and programs directed at informal households living with children under 60 months to alleviate food insecurity.
Preterm ETs Are Significantly Reduced Compared with Adults and Partially Reduced Compared with Term Infants
Authors: Wirkner Aila , Vogelgesang Antje , Hegge Ines , Lange Anja , Olbertz Dirk Manfred , Gerber Bernd , Heckmann Matthias , Ruhnau Johanna
Published: October 2022

The release of DNA by cells during extracellular trap (ET) formation is a defense function of neutrophils and monocytes. Neutrophil ET (NET) formation in term infants is reduced compared to adults. Objective: The aim was to quantify NET and monocyte ET (MET) release and the respective key enzymes myeloperoxidase (MPO) and neutrophil elastase (NE) in preterm infants. In this prospective explorative study, ET induction was stimulated by N-formylmethionine-leucyl-phenylalanine (fMLP), phorbol 12-myristate 13-acetate (PMA), lipopolysaccharide (LPS), and lipoteichoic acid (LTA) in the cord blood of preterm infants (n = 55, 23–36 weeks) compared to term infants and adults. METs were quantified by microscopy, and NETs by microscopy and flow cytometry. We also determined the MPO levels within NETs and the intracellular concentrations of NE and MPO in neutrophils. The percentage of neutrophils releasing ET was significantly reduced for preterm infants compared to adults for all stimulants, and with a 68% further reduction for PMA compared to term infants (p = 0.0141). The NET area was not reduced except for when fMLP was administered. The amount of MPO in NET-producing cells was reduced in preterm infants compared to term infants. For preterm infants, but not term infants, the percentage of monocytes releasing ETs was significantly reduced compared to healthy adults for LTA and LPS stimulation. Conclusion: In preterm infants, ETs are measurable parts of the innate immune system, but are released in a reduced percentage of cells compared to adults.
A Randomised Crossover Trial of Behaviour Guidance Techniques on Children with Special Health Care Needs during Dental Treatment: The Physiological Variations
Authors: Ismail Norsaima , Isa Khairil Anuar Md , Wan Mokhtar Ilham
Published: October 2022

Passive immobilisation is regarded as able to potentially cause physical distress and intense anxiety manifestations. The study aims to investigate the physiological variations of children with special health care needs while using a Papoose board and a combination of basic behaviour guidance during dental treatment. This is a randomised crossover trial involving 90 children with special health care needs receiving standard dental care with two methods of behaviour guidance sequentially. Exposure A is a combination of tell-show-do, distraction, and positive reinforcement, while exposure B is passive immobilisation with a Papoose board. The subject child’s blood pressure, heart rate, and oxygen saturation level were measured at four different times during dental treatment. In total, 74 children’s physiological data were successfully collected with a mean age of 9.85 years (SD = 2.71). Further, 64.9% of the children were diagnosed with autism spectrum disorder, 12.2% with attention deficit hyperactivity disorder, 9.5% with intellectual disability, 8.1% with Down syndrome, 2.2% with global developmental delay, and 1.1% with dyslexia and cerebral palsy, respectively. The measurement of children’s blood pressure, heart rate, and oxygen saturation level with the application of a Papoose board or a combination of the basic behaviour guidance revealed no significant changes (p > 0.05). The use of a Papoose board is safe and has no discernible influence on the child’s physiological responses.
High Prevalence of Hypovitaminosis D in Adolescents Attending a Reference Centre for the Treatment of Obesity in Switzerland
Authors: Patriota Pollyanna , Borloz Sylvie , Ruiz Inge , Bouthors Thérèse , Rezzi Serge , Marques-Vidal Pedro , Hauschild Michael
Published: October 2022

Background: Hypovitaminosis D is common in populations with obesity. This study aimed at assessing (1) the prevalence of hypovitaminosis D and (2) the associations between vitamin D levels and cardiovascular risk factors in adolescents attending a reference centre for the treatment of obesity. Design: Cross-sectional pilot study conducted in the paediatric obesity unit of the Lausanne university hospital, Switzerland. Methods: Participants were considered eligible if they (1) were aged between 10 to 16.9 years and (2) consulted between 2017 and 2021. Participants were excluded if (1) they lacked vitamin D measurements or (2) the vitamin D measurement was performed one month after the base anthropometric assessment. Hypovitaminosis D was considered if the vitamin D level was <30 ng/mL (<75 nmol/L). Severe obesity was defined as a BMI z-score > 3 SD. Results: We included 52 adolescents (31% girls, mean age 13 ± 2 years, 33% with severe obesity). The prevalence of hypovitaminosis D was 87.5% in girls and 88.9% in boys. The vitamin D levels were inversely associated with BMI, Spearman r and 95% CI: −0.286 (−0.555; −0.017), p = 0.037; they were not associated with the BMI z-score: −0.052 (−0.327; 0.224), p = 0.713. The vitamin D levels were negatively associated with the parathormone levels (−0.353 (−0.667; −0.039), p = 0.028) and positively associated with the calcium levels (0.385 (0.061; 0.708), p = 0.020), while no association was found between vitamin D levels and blood pressure and lipid or glucose levels. Conclusion: almost 9 out of 10 adolescents with obesity in our cohort presented with hypovitaminosis D. Hypovitaminosis D does not seem to be associated with a higher cardiovascular risk profile in this group.
The Effect of Pythagorean Self-Awareness on Heart Rate Variability, Perceived Stress and Behavior of Preschool Children
Authors: Angelopoulou Kyriaki , Zaverdinou Eleni , Bacopoulou Flora , Chrousos George P. , Giannakakis Giorgos , Kanaka-Gantenbein Christina , Mavrogeni Sophie , Charalampopoulou Maria , Katimertzi Maria , Darviri Christina
Published: October 2022

Stress is associated with unhealthy habits and non-communicable diseases. It is also linked to communicable diseases due to its impact on immune function. These can be prevented through intervention programs in schools. The aim of this study was to examine the effect of the simplified Pythagorean Self-Awareness Intervention on heart rate variability (HRV) parameters, perceived stress and behaviors of preschool children. The sample of the study consisted of 45 preschool students. A “one group (double) pretest—posttest design” was used, to allow for comparisons of the measurements before and after the intervention. Students were assessed via two questionnaires (“Perceived Stress Scale for Children” (PSS-C) and “Checklist for Screening Behavioral Problems in Preschool Children”) and a photoplethysmographic (PPG) device. The intervention lasted 9 weeks and included practicing of the Pythagorean Self-awareness techniques and the adoption of healthy behaviors. The results showed no statistically significant differences between the two pretests (p > 0.05 for all comparisons) and statistically significant differences between the second pretest and posttest (“Perceived Stress Scale for Children”, (PSS-C) p < 0.0001, “Checklist for Screening Behavioral Problems in Preschool Children” p < 0.0001 and two indices of PPG device: heart rate mean, p < 0.0001, low frequency/very low frequency, p = 0.034). In conclusion, the Pythagorean Self-Awareness Intervention had a beneficial effect on the sample of preschool students examined, as the results showed an improvement in the perceived stress and the HRV parameters tested, and in engaging healthier behaviors, findings that indicate a relaxed psychologic state and a healthier lifestyle.
An Under-Recognized Disease: A Rare Case of Idiopathic CD4 Lymphopenia Mislabeled as Primary Ciliary Dyskinesia
Authors: Bukhamseen Fatimah , Al-Shamrani Abdullah
Published: October 2022

Idiopathic CD4 Lymphopenia is a heterogeneous condition, recognized in the late 20th century, with a wide spectrum of presentations, requiring a high index of suspicion to avoid misdiagnosing the condition. This case highlights the diversity in its clinical presentations in the context of an autosomal dominant pattern of inheritance. We are reporting a case of a nine-year-old child, initially labelled by her primary treating hospital as primary ciliary dyskinesia after presenting with chronic cough, purulent nasal discharge, and recurrent chest infections. She was referred to our facility, a tertiary center, as her condition marginally improved. After the patient has undergone a comprehensive diagnostic workup, including a gene study, she was found to be carrying a mutation known to cause idiopathic CD4 lymphopenia. Extended work up of her family showed that two of her siblings have inherited an autosomal dominant mutation from their mother who had a milder form of the disease. This condition is an extremely rare condition in children, which can be easily mislabeled. Thus, healthcare providers should avoid labeling certain long-standing diseases unless the diagnosis has been established. We encourage leveraging the use of the latest revolutionary genetic testing techniques to confirm the diagnosis of such puzzling cases.
The Integrated Circuit Industry at a Crossroads: Threats and Opportunities
Authors: Pennisi Salvatore
Published: October 2022

With the outbreak of the COVID-19 pandemic, the persistent chip shortage, war in Ukraine, and U.S.–China tensions, the semiconductor industry is at a critical stage. Only if it is capable of major changes, will it be able to sustain itself and continue to provide solutions for ongoing exponential technology growth. However, the war has undermined, perhaps definitively, a global order that urged the integration of markets above geopolitical divergences. Now that the trend seems to be reversed, the extent to which the costs of this commercial and technological decoupling can be absorbed and legitimized will have to be understood.
Identification of Gut Microbiota Affecting Fiber Digestibility in Pigs
Authors: Niu Qing , Pu Guang , Fan Lijuan , Gao Chen , Lan Tingxu , Liu Chenxi , Du Taoran , Kim Sung Woo , Niu Peipei , Zhang Zongping , Li Pinghua , Huang Ruihua
Published: October 2022

Dietary fiber plays an important role in porcine gut health and welfare. Fiber is degraded by microbial fermentation in the intestine, and most gut microbiota related to fiber digestibility in pigs are worth pursuing. The aim of this study was to identify gut microbiota associated with the apparent total tract digestibility (ATTD) of neutral detergent fiber (NDF) and of acid detergent fiber (ADF) in pigs. Large phenotypic variations in the ATTD of NDF and of ADF were separately found among 274 Suhuai pigs. Microbial community structures were significantly different between high and low fiber digestibility groups. Fourteen genera separately dominated the communities found in the high ATTD (H-AD) of NDF and ADF samples and were in very low abundance in the low ATTD (L-AD) of NDF and ADF samples. In conclusion, norank_f__Bacteroidales_S24-7_group (p < 0.05), Ruminococcaceae_UCG-005 (p < 0.05), unclassified_f__Lachnospiraceae (p < 0.05), Treponema_2 (p < 0.01), and Ruminococcaceae_NK4A214_group (p < 0.01) were the main genera of gut microbiota affecting the ATTD of NDF in pigs. Christensenellaceae_R-7_group (p < 0.01), Treponema_2 (p < 0.05), Ruminococcaceae_NK4A214_group (p < 0.05), Ruminococcaceae_UCG-002 (p < 0.05), and [Eubacterium]_coprostanoligenes_group (p < 0.05) were the main genera of gut microbiota affecting the ATTD of ADF in pigs. The most important functions of the above different potential biomarkers were: carbohydrate transport and metabolism, general function prediction only, amino acid transport and metabolism, cell wall/membrane/envelope biogenesis, translation, transcription, replication, energy production and conversion, signal transduction mechanisms, and inorganic ion transport and metabolism. The most important metabolic pathways of the above different potential biomarkers were: membrane transport, carbohydrate metabolism, amino acid metabolism, replication and repair, translation, cell motility, energy metabolism, poorly characterized, nucleotide metabolism, metabolism of cofactors and vitamins, and cellular processes and signaling.
Suppressive Effects of 4-(Phenylsulfanyl) Butan-2-One on CCL-1 Production via Histone Acetylation in Monocytes
Authors: Tsai Ming-Kai , Tsai Mei-Lan , Wen Zhi-Hong , Liao Wei-Ting , Lin Yi-Ching , Chiou Hsin-Ying Clair , Lin Ming-Hong , Hung Chih-Hsing
Published: October 2022

The 4-(phenylsulfanyl) butan-2-one (4-PSB-2), a marine-derived compound from soft coral, was proven to have multiple biological activities including neuroprotection and potent anti-inflammatory effects. CC chemokine ligand (CCL)-1 belongs to T helper (Th)2-related chemokines that are involved in the recruitment of Th2 inflammatory cells. Histone acetylation has been recognized as a critical mechanism underlying the regulated cytokine and chemokine production. Our study tried to investigate the anti-inflammatory effect of 4-PSB-2 on CCL-1 production in human monocytes and explore possible underlying intracellular processes, including epigenetic regulation. To confirm our hypothesis, human monocyte THP-1 cell line and primary CD14+ cells were pretreated with various concentrations of 4-PSB-2 and then were stimulated with lipopolysaccharide (LPS). The CCL-1 concentration was measured by enzyme-linked immunosorbent assays, and the intracellular signaling pathways and epigenetic regulation of 4-PSB-2 were investigated by using Western blotting and chromatin immunoprecipitation analysis. In this study, we found that 4-PSB-2 had a suppressive effect on LPS-induced CCL-1 production. Moreover, this suppressive effect of 4-PSB-2 was mediated via intracellular signaling such as the mitogen-activated protein kinase and nuclear factor-κB pathways. In addition, 4-PSB-2 could suppress CCL-1 production by epigenetic regulation through downregulating histone H3 and H4 acetylation. In short, our study demonstrated that 4-PSB-2 may have a potential role in the treatment of allergic inflammation.
Pro-Inflammatory and Anti-Inflammatory Salivary Cytokines in Breast Cancer: Relationship with Clinicopathological Characteristics of the Tumor
Authors: Bel’skaya Lyudmila V. , Loginova Alexandra I. , Sarf Elena A.
Published: October 2022

The aim of the work was to compare the salivary cytokine profile of breast cancer patients with the clinicopathological characteristics of the tumor. The study included 113 patients with breast cancer (main group, mean age 54.1 years) and 111 patients with breast fibroadenomas (control group, mean age 56.7 years). Before treatment, saliva samples were collected from all patients and the content of cytokines (IL-1β, IL-2, IL-4, IL-6, IL-8, IL-10, IL-18, MCP-1, and TNF-α) was determined. The content of cytokines in saliva correlates well with the clinicopathological characteristics of breast cancer. The level of all salivary cytokines increases at advanced stages of breast cancer and at a low degree of tumor differentiation. The exception is MCP-1, for which there is an extremely high content for well-differentiated breast cancer. A statistically significant increase in the content of MCP-1, IL-1β, IL-2, IL-4, and IL-10 was found in triple-negative breast cancer. For the first time, the correlation of salivary levels of TNF-α, IL-1β, and IL-6 with HER2 status, MCP-1, IL-1β, IL-2, and IL-4 with the hormonal status of the tumor was shown. The relationship between the level of IL-2, IL-10, and IL-18 in saliva with the level of Ki-67 expression has been established.
Sustainable Synthesis of FITC Chitosan-Capped Gold Nanoparticles for Biomedical Applications
Authors: De Matteis Valeria , Rizzello Loris , Cascione Mariafrancesca , Pellegrino Paolo , Singh Jagpreet , Manno Daniela , Rinaldi Rosaria
Published: October 2022

The quest for novel nanoscale materials for different applications necessitates that they are easy to obtain and have excellent physical properties and low toxicity. Moreover, considering the ongoing environmental impact of noxious chemical waste products, it is important to adopt eco-friendly approaches for nanoparticle synthesis. In this work, a natural polymer (medium molecular weight chitosan) derived from chitin was employed as a reducing agent to obtain gold nanoparticles (AuNPs) with a chitosan shell (AuNPs@CS) by a microwave oven. The chitosan is economically viable and cost-competitive in the market showing also nontoxic behavior in the environment and living organisms. The synthesized AuNPs@CS-FITC NPs were fully characterized by spectroscopic and microscopic characterization techniques. The size distribution of NPs was about 15 nm, which is a suitable dimension to use in biomedical applications due to their high tissue penetration, great circulation in blood, and optimal clearance as well as low toxicity. The prepared polymer-capped NPs were further functionalized with a fluorescent molecule, i.e., Fluorescein-5-isothiocyanate (FITC), to perform imaging in the cell. The results highlighted the goodness of the synthesis procedure, as well as the high internalization rate that resulted in an optimal fluorescence intensity. Thus, this work presents a good sustainable/green approach-mediated polymer nanocomposite for various applications in the field of diagnostic imaging.
Real-Driving Emissions of an Aging Biogas-Fueled City Bus
Authors: Spoof-Tuomi Kirsi , Arvidsson Hans , Nilsson Olav , Niemi Seppo
Published: October 2022

Transition to low emission transportation and cleaner cities requires a broad introduction of low- and zero-carbon alternatives to conventional petrol- and diesel-powered vehicles. New-generation gas buses are a cost-effective way to reduce local air pollutants from urban transportation. Moreover, major greenhouse gas (GHG) savings may be achieved using biogas as the power source. The main objective of this research was to investigate CH4 and other gaseous emissions of a biogas-fueled urban bus equipped with a three-way catalyst (TWC) in real-world conditions. The study focused on emissions from a six-year-old gas-powered city bus, supplementing emission data from aging bus fleets. Impaired CH4 oxidation and NOx reduction were observed in the catalyst after its service life of 375,000 km–400,000 km. The main reason for low CH4 and NOx conversion over the TWC was concluded to be the partial deactivation of the catalyst. Another critical issue was the fluctuating air-to-fuel ratio. The results show that the efficiency of exhaust after-treatment systems should be closely monitored over time, as they are exposed to various aging processes under transient driving conditions, leading to increased real-world emissions. However, the well-to-wheels (WTW) analysis showed that an 80% GHG emission benefit could be achieved by switching from diesel to biomethane, giving a strong environmental argument for biogas use.
Compound Risk of Air Pollution and Heat Days and the Influence of Wildfire by SES across California, 2018–2020: Implications for Environmental Justice in the Context of Climate Change
Authors: Masri Shahir , Jin Yufang , Wu Jun
Published: October 2022

Major wildfires and heatwaves have begun to increase in frequency throughout much of the United States, particularly in western states such as California, causing increased risk to public health. Air pollution is exacerbated by both wildfires and warmer temperatures, thus adding to such risk. With climate change and the continued increase in global average temperatures, the frequency of major wildfires, heat days, and unhealthy air pollution episodes is projected to increase, resulting in the potential for compounding risks. Risks will likely vary by region and may disproportionately impact low-income communities and communities of color. In this study, we processed daily particulate matter (PM) data from over 18,000 low-cost PurpleAir sensors, along with gridMET daily maximum temperature data and government-compiled wildfire perimeter data from 2018–2020 in order to examine the occurrence of compound risk (CR) days (characterized by high temperature and high PM2.5) at the census tract level in California, and to understand how such days have been impacted by the occurrence of wildfires. Using American Community Survey data, we also examined the extent to which CR days were correlated with household income, race/ethnicity, education, and other socioeconomic factors at the census tract level. Results showed census tracts with a higher frequency of CR days to have statistically higher rates of poverty and unemployment, along with high proportions of child residents and households without computers. The frequency of CR days and elevated daily PM2.5 concentrations appeared to be strongly related to the occurrence of nearby wildfires, with over 20% of days with sensor-measured average PM2.5 > 35 μg/m3 showing a wildfire within a 100 km radius and over two-thirds of estimated CR days falling on such days with a nearby wildfire. Findings from this study are important to policymakers and government agencies who preside over the allocation of state resources as well as organizations seeking to empower residents and establish climate resilient communities.
Control of Static and Dynamic Parameters by Fuzzy Controller to Optimize Friction Stir Spot Welding Strength
Authors: Lashin Maha M. A. , Al Samhan Ali M. , Badwelan Ahmed , Khan Muhammad Ijaz
Published: October 2022

Solid-state welding is a derivative of the friction stir spot welding (FSSW) technique, which has been developed as a new method for joining aluminum alloys. FSSW is a variant of linear friction stir welding intended to deal with lightweight alloy resistance spot welding (RSW) and riveting. Tensile strength refers to a material’s ability to withstand excessive stress when being stretched or pulled before necking; it is expressed in terms of force per unit area. The tensile strength in stir spot welding is affected by dynamic and static parameters. The control of dynamic parameters and static parameters is studied in this paper to optimize the friction stir spot welding strength. A fuzzy logic control system is used to optimize the process as a new approach that can be used in this field. The obtained results prove that the fuzzy logic control system is an easy and inexpensive technology that can be used in prediction and optimization for the strength of FSSW. Furthermore, the results show the efficacy and adequacy of the proposed fuzzy logic control system.
Laser Cladding-Based Surface Modification of Carbon Steel and High-Alloy Steel for Extreme Condition Applications
Authors: John Merbin , Kuruveri Udaya Bhat , Menezes Pradeep L.
Published: October 2022

Laser cladding (LC) is a laser-based surface modification technique widely adopted to develop a thin coating or remanufacture worn-out mechanical components that work in extreme conditions. LC helps to generate superior surface properties and surface integrity on the substrate surface, improving the service life. This review paper provides a comprehensive overview of the LC process, different powder feeding methods, and the uniqueness of LC over other coating techniques. More specifically, the current state-of-the-art of the LC process on carbon steel and high-alloy steel-based mechanical components operating in diverse industries was elucidated. Furthermore, the effect of LC processes on mechanical properties such as wear, corrosion and fatigue properties are discussed. In addition, the LC process’s influence on microstructural features and microstructural modifications is explained. Finally, this study explores some potential applications of the LC process in diverse industries.
Influence of Metal Oxide Nanoparticles as Antimicrobial Additives Embedded in Waterborne Coating Binders Based on Self-Crosslinking Acrylic Latex
Authors: Steinerová Denisa , Kalendová Andréa , Machotová Jana , Knotek Petr , Humpolíček Petr , Vajdák Jan , Slang Stanislav , Krejčová Anna , Beneš Ludvík , Wolff-Fabris Felipe
Published: October 2022

This article deals with the simple preparation of environmentally friendly acrylic latex binders, which are functionalized with nanoparticles of metal oxides, namely MgO, ZnO, La2O3 and combinations of MgO and ZnO, serving as functional components to achieve antimicrobial properties, but also to improve physical–mechanical properties and chemical resilience. The incorporation of uncoated powder nanoparticles was performed during the synthesis, using the two-stage semi-continuous emulsion radical polymerization technique, to obtain latexes containing 0.5%–1.3% nanoparticles relative to the polymer content. Changes in latex performance due to nanoparticles were compared from the point of view of the type and concentration of metal oxide nanoparticles in latex. The results of the tests showed that all types of nanoparticles showed very promising properties, while with increasing concentration of nanoparticles there was an improvement in properties. The nanoparticles in latex provided interfacially crosslinked transparent smooth coating films with high gloss and good physical–mechanical properties. Latexes containing the highest concentration of nanoparticles provided coatings with significant antimicrobial activity against all tested bacterial and fungal strains, but also in-can preservative stability of liquid latex. Furthermore, the coatings were resistant to solvents, and in addition, latexes with MgO nanoparticles showed a significant decrease in the minimum film-forming temperature, and latex with a concentration of about 1.3% MgO did not show any flash corrosion under the coating film cast on a steel substrate. The latexes containing MgO and La2O3 nanoparticles provided coatings that were very resistant to water bleaching.
Research Progress on Construction of Lutein-Loaded Nano Delivery System and Their Improvements on the Bioactivity
Authors: Ma Yongqiang , You Tingting , Wang Jing , Jiang Yan , Niu Jichao
Published: October 2022

Lutein belongs to the diverse group of pigments known as oxygenated carotenoids, also known as phytochrome and macular pigment, demonstrating excellent biological activity. However, its application is limited due to the difficulty of dissolution, poor stability, and low bioavailability. To solve these problems, delivery systems are considered to be one of the most promising choices. These delivery systems can improve the physical, chemical, and biological properties of lutein to a certain extent. Moreover, the system can also be adapted to the needs of production in our daily life. In this paper, the construction of lutein-loaded nano delivery systems and their influences on the bioactivity of lutein were reviewed based on previous researchers. The main materials were classified, and assistant substances, basic parameters, and properties were collected. The mechanisms were analyzed in terms of enhancing cellular uptake, improving bioavailability, and achieving targeted delivery. These results show that different materials have their own characteristics. This review aims to provide references for the production and application of lutein in the food industry.
Effects of 3D Roughness Parameters of Sandblasted Surface on Bond Strength of HVOF Sprayed WC-12Co Coatings
Authors: Wang Jing , Ai Chao , Yun Xiao , Chen Zhikai , He Bing
Published: October 2022

This work aims to reveal the effects of 3D roughness parameters of sandblasted surfaces on bond strength between thermal spray coatings and substrates. The investigation was carried out on the surface of AISI 4140, which were pretreated with automatic-sandblasting system. 3D topography and roughness parameters were analyzed by a 3D optical profiler. The bond strength of WC-12Co coatings was measured using a pull-off test method. Scanning electron microscope revealed that the morphology of the surface after sandblasting was rough. Furthermore, the surface topography was characterized by several irregular peaks and pits with different directions and no fixed orientation randomly distributed on sandblasted surface. The average values for surface roughness Sa = 4.84 ± 0.34 μm and bond strength = 32.8 ± 2.8 MPa were obtained. In terms of 3D roughness parameters, Sa, Sdr, Sdq and Sq were found to have more significant impact on affecting the bond strength, showing a nonlinear regression relationship. Furthermore, bond strength was positively correlated with Sa, Sdr and Sdq, while inversely proportional to Sq. This confirmed that a greater surface roughness of a sandblasted surface was not more conducive to the improvement of bond strength. The influence mechanism of each parameter was discussed, which was consistent with the regression mathematical model.
Study on Key Parameters for Jet Impacting Pulverized Coal Deposited in Coal-Bed Methane Wells
Authors: Zhu Hongying , Xue Likun , Zhang Fenna , Qi Yaoguang , Zhao Junwei , Feng Dehua
Published: October 2022

Cleaning out the pulverized coal deposited at the bottom of a coalbed methane (CBM) well is key to achieving continuous CBM drainage and prolonging the workover period. In this study, Fluent is used in conjunction with the standard k-ε model and the Eulerian-Eulerian model to simulate and analyse jet erosion of deposited pulverized coal particles. The depth and width of the stable erosion pit that is formed by jet-impacting deposited pulverized coal under different conditions are determined and provide a theoretical basis for the cleanout of pulverized coal in the bottom of a CBM well. In this paper, the three parameters of the jet target distance, nozzle diameter and nozzle outlet flow velocity are selected to perform an orthogonal simulation. The change trends in the depth and width of the scouring pit with time are determined. The results show that jet impacting of deposited pulverized coal can be categorised into four stages, periods of rapid growth, stability, jet swing and dynamic stability. A sensitivity analysis shows that the nozzle outlet flow velocity has the strongest influence on the depth of the scouring pit among the selected parameters. The depth of the jet impact pit can reach the maximum depth at t = 3 s, while the width of the impact pit can reach the maximum after t = 7 s. This can provide key design parameters for CBM well pulverized coal impacting operation. It is of great significance for capacity damage control during CBM well workover operation.
Study on the Performance of Ag-Cu Bimetal SERS Substrate
Authors: Song Xiaolong , Yan Xiaoya , Li Na , Shen Lin , Wang Mingli
Published: October 2022

SERS has become a powerful trace detection technology, but its practical application is often limited by the fixed optical properties of cast metals (Au, Ag and Cu). In this paper, the bimetallic nanostructures prepared by changing the metal content ratio can regulate the different optical responses of the substrate. In addition, it was found that the scale of moth wings (MW) with 3D grating-like uniform nanoarrays using bioscaffold can provide a consistently high-density ‘hot spot’ for the as-prepared plasmonic substrate. Here, two different methods (i) co-sputtered with different times and (ii) sputtered with sequentially alternating to form a stratified structure on the MW were employed for the fabrication of SERS-active substrates, and they were named AgCu@MW and Ag@Cu@MW, respectively. The comparison SERS measurement results of the above two substrates by using probe molecules R6G and MB show that the stratified structure of the Ag@Cu@MW-3 substrate has higher SERS performance. This strategy can not only prepare plasma substrates with on-demand optical responses but also provide new ideas for the preparation of conventional biomimetic nanomaterials.
Clinical Accuracy of Splintless Maxillary Positioning with Aid of CAD/CAM Fabricated Surgical Cutting Guides and Titanium Plates
Authors: Zotti Rinaldo , Oliva Giorgio , Tian Carlo , Isola Gaetano , Dalessandri Domenico , Zanetti Umberto , Bianchi Ilenia , Bonetti Stefano
Published: October 2022

New digital technologies are improving the accuracy of orthognathic surgery. One of the new approaches transfers the surgical plan into real surgery without using an occlusal splint. This pilot study aims to validate the splintless approach to orthognathic surgery on a series of cases. Five patients were enrolled. Surgeries were planned using a digital surgical simulation method thanks to three-dimensional images. The splintless surgical approach was planned for maxillary reposition. This consisted of cutting guides and three-dimensionally (3D) printed custom titanium plates. These two were created using the computer-aided design and computer-aided manufacturing (CAD-CAM) technique and were used intraoperatively to guide the osteotomy and repositioning of the bony segments without the use of the surgical splint. The difference between the planned surgery and the real final position was analyzed thanks to superimposition techniques and landmark analysis. Statistical tests were performed to detect significant differences. No difference was found in any of the landmarks. Midline landmarks differed from the planned position by 0.34 mm. Higher variability was found in the posterior landmark. These findings suggest that a splintless approach is useful in transferring the surgical plan without using an occlusal splint.
Metakaolin-Reinforced Sulfoaluminate-Cement-Solidified Wasteforms of Spent Radioactive Resins—Optimization by a Mixture Design
Authors: Xu Jiaqian , Wang Mengzhou , Li Cong , Han Mengxing , Wang Qi , Sun Qina
Published: October 2022

Cement solidification is a main technique for radioactive waste treatment to reduce its risk to the environment and human health. However, this method underperforms when dealing with spent radioactive ion-exchange resin, taking much space, and costing much money for final disposal. In this work, simulated spent radioactive resin was solidified using a metakaolin-reinforced sulfoaluminate cement system, which was optimized by a mixture design based on the effects of components and parameters, and the durability of solidified wasteforms was assessed in terms of strength and Cs(I) leaching. Solidified by an optimized formula of 40 wt.% spent resin, 55.8 wt.% sulfoaluminate cement, 2.2 wt.% metakaolin, and 2 wt.% water reducer, the resin loading in wasteforms reached 64% and the compressive strength 13.7 MPa. The dominant mineral phases of hydration products were ettringite crystalline of acicular and columnar morphology, with small amounts of scattered amorphous clusters of aluminum gels and C–S–H gels. Metakaolin, a source of aluminum, promoted the growth of ettringite, which facilitated (1) the encapsulation of resin beads with high strengths, even in acidic environments or during frequent freezing-thawing, and (2) the retention of Cs(I), with a 42 day leaching rate of 2.3 × 10−4 cm/day. This work offers a technical justification for spent resin solidification in the metakaolin-reinforced sulfoaluminate cement system, which is an applicational solution for the efficient treatment of radioactive waste.
Enhanced Red Emissions of Europium (III) Chelates in RNA–OTMA Complexes
Authors: Liang Lijuan , Zhang Nianjie , Cao Rong , Wang Suyun , Liu Shengzhen , Yu Zhaohui , Liu Quanxiao , Wang Jigang , Li Zhenjun , Jiang Tao
Published: October 2022

In recent years, biopolymers have been widely used in optoelectronic devices because of their unique structure, novel optical and physical properties. In this paper, novel RNA-based photofunctional materials were fabricated by associating an RNA–OTMA (octadecyltrimethylammonium chloride) lipid complex with a luminescent Eu (III) complex. The fluorescence emission intensity, fluorescence quantum yield and fluorescence lifetime were characterized in both solution and thin film states, and the interaction between the RNA–OTMA lipid complex and Eu (III) complexes was analyzed. This study suggests that the luminescence performance of the Eu (III) complexes doped with RNA–OTMARNA–OTMA was significantly enhanced compared with those of the complex in a conventional poly (methyl methacrylate) matrix, thereby providing an important basis for the application of biomaterials in optoelectronic devices.
Comparative Study of Carbonaceous and Polymer Conductive Additives on Anticorrosion Performance of Epoxy Zinc-Rich Primer
Authors: Lv Xiao , Jin Xuliang , Zhang Zongxuan , Bai Yuxing , Guo Tingting , Zhang Li , Zhang Hui , Zhu Jesse , Shao Yuanyuan , Zhang Haiping , Yuan Bin , Yin Aiming , Nie Jinfeng , Cao Fan , Xu Zhengjun
Published: October 2022

Zinc-rich primers are among the most promising organic coating systems for improving the corrosion resistance of metals in the marine environment. However, the high zinc content results in poor coating adhesion, high cost, insecurity and pollution. To decrease the zinc dust content, the carbonaceous and polymer conductive additives carbon black (CB), conductive graphite (CG), multiwalled carbon nanotubes (MWCNT) and polyaniline (PANI) were introduced to partially replace the zinc dust in the primers. A comparative study of the anticorrosion performance of epoxy zinc-rich primer (ZRP) is presented herein to systematically discuss and elaborate on the effects of the different conductive additives. There were no blisters, rust or corrosion products presented on the coatings of the CB-modified series due to the good dispersion and conductivity of nanosized CB clusters, while the zinc corrosion products covered the surface of the MWCNT-modified series samples, which was attributed to the excessive electrical conductivity resulting in high consumption of zinc powder. The lamellar CG provided an additional blocking barrier for the coatings based on the maze effect. The transition from the intrinsic state to the doped state of PANI resulted in corrosion protection for the coatings depending on the cathodic and barrier function. The experimental results suggested that the formula with 2 wt.% CB and 67 wt.% zinc dust had the most promising anticorrosion properties, which was also demonstrated by the high Rct and low CPEdl values calculated according to the equivalent electrical circuit analyses.
Polymer Coatings Based on Polyisobutylene, Polystyrene and Poly(styrene-block-isobutylene-block-styrene) for Effective Protection of MXenes
Authors: Maltanava Hanna , Shiman Dmitriy , Ovodok Evgeni , Svito Ivan , Makarevich Miraslau , Kostjuk Sergei , Poznyak Sergey , Aniskevich Andrey
Published: October 2022

MXene films with a conductivity of about 4000 S/cm were obtained on glass substrates following a drop-casting method and characterized by scanning electron microscopy (SEM), X-ray diffraction analysis (XRD) and Raman spectroscopy. The polymer coatings of polystyrene (PSt), polyisobutylene (PIB) and tri-block copolymer of polyisobutylene with styrene (SIBS) were deposited on MXene films and their efficiency toward the protection of MXenes against oxidative degradation was estimated at ambient conditions. A loss of conductivity was detected for PSt-coated MXene films after 220 days of storage, while pristine MXene films stored for 400 days were conductive and their resistivity increased by 2.5 times. Nonpolar polymer coatings based on polyisobutylene and tri-block copolymer of isobutylene with styrene showed ability to protect MXene films from oxidation during a long-term period. After 400 days of storage, the resistivity of the MXene films coated with PIB and SIBS increased by 1.8 and 1.4 times, respectively. The results obtained are of interest for expanding the industrial application of MXene films, increasing their operation by simple coating with nonpolar flexible polymers.
Hybrid Steel Fiber of Rigid Pavements: A 3D Finite Element and Parametric Analysis
Authors: Al Harki Bakhtiyar Q. Khawaja , Al Jawahery Mohammed S. , Abdulmawjoud Ayman A.
Published: October 2022

Rigid pavements have high compressive strength and low flexural strength due to the brittleness of concrete. This leads to the formation of cracks easily under the applied loads of vehicles; therefore, the design of concrete pavements usually leads to an increase in the high thicknesses. Hybrid steel fibers are used in concrete to increase flexural strength and minimize crack formation. Using concrete with steel fibers in pavements reduces the required concrete thickness. In recent decades, the application of the finite element method to predict the behavior of rigid pavements has increased. This study investigates the influence of hybrid steel fiber on the behavior of rigid pavements; a finite element modeling approach is used to simulate the case study. Several parameters are entered and investigated in this study, including the proportion mix of hybrid fiber concrete (HFC), which contains 0.2% macro synthetic fibers and 0.68, 0.8, and 0.96% of steel fibers, compressive strengths of 25, 35, and 45 MPa, slab thicknesses of 150, 200, and 250 mm, and the load of the tandem axle at the edge of mid slab on the Winkler foundation. The ATENA software package is used to perform a nonlinear finite element analysis. Thirty-six rigid specimen pavements with dimensions of 3600 × 3600 mm were modeled in this investigation. The results showed that the addition ratio (0.68 + 0.2)% of hybrid fibers is more effective in improving the load bearing capacity with a slab thickness of 150 mm and 25 MPa compressive strength.
Mechanism of the Influence of Weld Pool Wall Constraint on Weld Profile Formation in Gas Metal Arc Welding of Aluminum Alloy
Authors: Zhang Zhanhui , Liu Guiqian , Jiang Quan , Han Leigang
Published: October 2022

This paper aims to clarify the influence of the wall constraint on the convection behavior of molten metal in a molten pool and improve the weld formation and mechanical property. In this paper, the flow behavior of molten metal under the action of weld pool wall constraint and driving forces is studied; especially, the mechanism of weld pool wall constraint on the flow behavior of molten metal and its influence on the weld formation are studied and verified. Additionally, the influence of convection behavior on the composition distribution and properties of weld are explored. The results show that the bottom wall of the molten pool has the function of constraint on the molten metal, which directly determines the profile and size of the upper and lower reinforcement of the weld. Therefore, the reinforcement forming coefficient Rc is proposed to value the diversion ability of the bottom wall. Meanwhile, the EDS results demonstrate that the flow pattern of molten metal has a significant effect on the distribution of the weld composition for different profiles of weld. For the weld with depressed upper reinforcement, its mechanical properties can be significantly improved because of its enhanced wall constraint when the supporting plate is added.