bluuebunny/crossref_metadata_2025 huggingface dataset:
Investigating the Regulatory Mechanism of the Sesquiterpenol Nerolidol from a Plant on Juvenile Hormone-Related Genes in the Insect Spodoptera exigua
Authors: Dai Hanyang , Liu Baosheng , Yang Lei , Yao Yu , Liu Mengyun , Xiao Wenqing , Li Shuai , Ji Rui , Sun Yang
Published: August 2023

Various plant species contain terpene secondary metabolites, which disrupt insect growth and development by affecting the activity of juvenile hormone-degrading enzymes, and the juvenile hormone (JH) titers maintained in insects. Nerolidol, a natural sesquiterpenol belonging to the terpenoid group, exhibits structural similarities to insect JHs. However, the impact of nerolidol on insect growth and development, as well as its underlying molecular mechanism, remains unclear. Here, the effects of nerolidol on Spodoptera exigua were investigated under treatment at various sub-lethal doses (4.0 mg/mL, 1.0 mg/mL, 0.25 mg/mL). We found that a higher dose (4.0 mg/mL) of nerolidol significantly impaired the normal growth, development, and population reproduction of S. exigua, although a relatively lower dose (0.25 mg/mL) of nerolidol had no significant effect on this growth and development. Combined transcriptome sequencing and gene family analysis further revealed that four juvenile hormone esterase (JHE)-family genes that are involved in juvenile hormone degradation were significantly altered in S. exigua larvae after nerolidol treatment (4.0 mg/mL). Interestingly, the juvenile hormone esterase-like (JHEL) gene Sexi006721, a critical element responsive to nerolidol stress, was closely linked with the significant augmentation of JHE activity and JH titer in S. exigua (R2 = 0.94, p < 0.01). Taken together, we speculate that nerolidol can function as an analog of JH by modulating the expression of the enzyme genes responsible for degrading JH, resulting in JH disorders and ultimately disrupting the development of insect larvae. This study ultimately provides a theoretical basis for the sustainable control of S. exigua in the field whilst proposing a new perspective for the development of novel biological pesticides.
Circulating Citrate Is Associated with Liver Fibrosis in Nonalcoholic Fatty Liver Disease and Nonalcoholic Steatohepatitis
Authors: Amjad Waseem , Shalaurova Irina , Garcia Erwin , Gruppen Eke G. , Dullaart Robin P. F. , DePaoli Alex M. , Jiang Z. Gordon , Lai Michelle , Connelly Margery A.
Published: August 2023

Nonalcoholic fatty liver disease (NAFLD) is associated with mitochondrial damage. Circulating mitochondrial metabolites may be elevated in NAFLD but their associations with liver damage is not known. This study aimed to assess the association of key mitochondrial metabolites with the degree of liver fibrosis in the context of NAFLD and nonalcoholic steatohepatitis (NASH). Cross-sectional analyses were performed on two cohorts of biopsy-proven NAFLD and/or NASH subjects. The association of circulating mitochondrial metabolite concentrations with liver fibrosis was assessed using linear regression analysis. In the single-center cohort of NAFLD subjects (n = 187), the mean age was 54.9 ±13.0 years, 40.1% were female and 86.1% were White. Type 2 diabetes (51.3%), hypertension (43.9%) and obesity (72.2%) were prevalent. Those with high citrate had a higher proportion of moderate/significant liver fibrosis (stage F ≥ 2) (68.4 vs. 39.6%, p = 0.001) and advanced fibrosis (stage F ≥ 3) (31.6 vs. 13.6%, p = 0.01). Citrate was associated with liver fibrosis independent of age, sex, NAFLD activity score and metabolic syndrome (per 1 SD increase: β = 0.19, 95% CI: 0.03–0.35, p = 0.02). This association was also observed in a cohort of NASH subjects (n = 176) (β = 0.21, 95% CI: 0.07–0.36, p = 0.005). The association of citrate with liver fibrosis was observed in males (p = 0.005) but not females (p = 0.41). In conclusion, circulating citrate is elevated and associated with liver fibrosis, particularly in male subjects with NAFLD and NASH. Mitochondrial function may be a target to consider for reducing the progression of liver fibrosis and NASH.
Novel Biomarkers to Guide Immunotherapy De-Escalation in the Neoadjuvant Setting in Triple-Negative Breast Cancer
Authors: Gandhi Shipra
Published: August 2023

Triple-negative breast cancer (TNBC) has the highest incidence of disease recurrence and distant metastases among breast cancer subtypes, leading to significant rates of morbidity and mortality [...]
Daily Duration of Compression Treatment in Chronic Venous Disease Patients: A Systematic Review
Authors: Mirakhmedova Sevara , Amirkhanov Amirkhan , Seliverstov Evgenii , Efremova Oksana , Zolotukhin Igor
Published: August 2023

Background: There are no data on the daily regimen of compression therapy in patients with chronic venous disease. This systematic review aimed to establish the optimal daily duration of compression treatment. Methods: A systematic search of CENTRAL and MEDLINE was performed to identify RCTs, non-RCTs, reviews, systematic reviews, meta-analyses, and guidelines evaluating the use of compression regimens in the treatment of varicose veins. Results: Thirty-two RCTs, three non-RCTs, four observational studies, and two crossover trials reporting the duration and regimes of compression treatment fulfilled the inclusion criteria. The daily duration of compression was reported in patients after invasive treatment, for venous ulcer treatment, in patients with venous symptoms. The quality of the studies varied. We could not conduct a meta-analysis due to the heterogeneity of the research data and their quality. Twenty-three studies reported results of compression usage after invasive procedures. Eight studies reported daily duration regimens in patients with venous ulcers. Nine studies reported the impact of compression on venous symptoms and/or edema or limb volume change. One study was conducted to assess if compression improves QoL in venous patients. While there was a clear difference found in the daily duration depending on the clinical scenario, no data in support of exact regimens were found. Conclusions: There are no reliable data supporting exact daily regimens of compression treatment in various cohorts of CVD patients.
The Antifungal Fibers of Polyamide 12 Containing Silver and Metal Oxides
Authors: Latko-Durałek Paulina , Rzempołuch Józef , Staniszewska Monika , Rosłoniec Karina , Bil Monika , Kozera Rafał , Boczkowska Anna
Published: August 2023

The textile market is a vast industry that utilizes antimicrobial polymeric materials, including various types of fabrics, for medical and personal protection applications. Therefore, this study focused on examining four types of antimicrobial fillers, namely, metal oxides (zinc, titanium, copper) and nanosilver, as fillers in Polyamide 12 fibers. These fillers can be applied in the knitting or weaving processes to obtain woven polymeric fabrics for medical applications. The production of the fibers in this study involved a two-step approach: twin-screw extrusion and melt spinning. The resulting fibers were then characterized for their thermal properties (TGA, DSC), mechanical performance (tensile test, DMA), and antifungal activity. The findings of the study indicated that all of the fibers modified with fillers kill Candida albicans. However, the fibers containing a combination of metal oxides and silver showed significantly higher antifungal activity (reduction rate % R = 86) compared to the fibers with only a mixture of metal oxides (% R = 21). Furthermore, the inclusion of metal oxides and nanosilver in the Polyamide 12 matrix hindered the formation of the crystal phase and decreased slightly the thermal stability and mechanical properties, especially for the composites with nanosilver. It was attributed to their worse dispersion and the presence of agglomerates.
Overview of the Current State of Flexible Solar Panels and Photovoltaic Materials
Authors: Dallaev Rashid , Pisarenko Tatiana , Papež Nikola , Holcman Vladimír
Published: August 2023

The rapid growth and evolution of solar panel technology have been driven by continuous advancements in materials science. This review paper provides a comprehensive overview of the diverse range of materials employed in modern solar panels, elucidating their roles, properties, and contributions to overall performance. The discussion encompasses both traditional crystalline silicon-based panels and emerging thin-film technologies. A detailed examination of photovoltaic materials, including monocrystalline and polycrystalline silicon as well as alternative materials such as cadmium telluride (CdTe), copper indium gallium selenide (CIGS), and emerging perovskite solar cells, is presented. Furthermore, the impact of transparent conductive materials, encapsulation polymers, and antireflective coatings on solar panel efficiency and durability is explored. The review delves into the synergistic interplay between material properties, manufacturing processes, and environmental considerations. Through a comprehensive survey of materials utilized in modern solar panels, this paper provides insights into the current state of the field, highlighting avenues for future advancements and sustainable solar energy solutions.
Application of Steel Slag as an Aggregate in Concrete Production: A Review
Authors: Ren Zhengyi , Li Dongsheng
Published: August 2023

Steel slag is a solid waste produced in crude steel smelting, and a typical management option is stockpiling in slag disposal yards. Over the years, the massive production of steel slags and the continuous use of residue yards have led to vast occupation of land resources and caused severe environmental concerns. Steel slag particles can potentially be used as aggregates in concrete production. However, the volume stability of steel slag is poor, and the direct use of untreated steel slag aggregate (SSA) may cause cracking and spalling of concrete. The present research summarizes, analyzes, and compares the chemical, physical, and mechanical properties of steel slags. The mechanism and treatment methods of volume expansion are introduced, and the advantages, disadvantages, and applicable targets of these methods are discussed. Then, the latest research progress of steel slag aggregate concrete (SSAC) is reviewed. Using SSA leads to an increase in the density of concrete and a decrease in workability, but the mechanical properties and durability of SSAC are superior to natural aggregate concrete (NAC). Finally, future research in this field is proposed to motivate further studies and guide decision-making.
Application of Interval Analysis to Assess Concrete Cover Degradation in Accelerated Corrosion Tests
Authors: Recha Faustyn , Yurkova Kseniya , Krykowski Tomasz
Published: August 2023

This paper presents the application of interval algebra in affine formulation to assess damage propagation in test reinforced concrete elements subjected to accelerated corrosion of rebar, taking into account the uncertainty of parameters. Corrosion interactions were captured by introducing the interval tensor of the velocity of volumetric strain. Analysis of the model for limit values of velocities of volumetric strains (inf(ε¯˙V) and sup(ε¯˙V)) using the finite element method for locally and gradient-formulated concrete models with degradation, elastic, and elastic–plastic was conducted using ANSYS and ATENA software. Computer calculations were performed assuming a parameter uncertainty of 0, 10, and 20%. The results of the calculations were compared with the results of detailed tests of elements subjected to accelerated corrosion of reinforcement using an electrolyzer with full monitoring of the electrical parameters of the system. The obtained results of the calculations were verified using the Monte Carlo method, treating the model parameters as random variables with a uniform distribution.
Impact of Coated Zinc Oxide Nanoparticles on Photosystem II of Tomato Plants
Authors: Tryfon Panagiota , Sperdouli Ilektra , Adamakis Ioannis-Dimosthenis S. , Mourdikoudis Stefanos , Moustakas Michael , Dendrinou-Samara Catherine
Published: August 2023

Zinc oxide nanoparticles (ZnO NPs) have emerged as a prominent tool in agriculture. Since photosynthetic function is a significant measurement of phytotoxicity and an assessment tool prior to large-scale agricultural applications, the impact of engineered irregular-shaped ZnO NPs coated with oleylamine (ZnO@OAm NPs) were tested. The ZnO@OAm NPs (crystalline size 19 nm) were solvothermally prepared in the sole presence of oleylamine (OAm) and evaluated on tomato (Lycopersicon esculentum Mill.) photosystem II (PSII) photochemistry. Foliar-sprayed 15 mg L−1 ZnO@OAm NPs on tomato leaflets increased chlorophyll content that initiated a higher amount of light energy capture, which resulted in about a 20% increased electron transport rate (ETR) and a quantum yield of PSII photochemistry (ΦPSII) at the growth light (GL, 600 μmol photons m−2 s−1). However, the ZnO@OAm NPs caused a malfunction in the oxygen-evolving complex (OEC) of PSII, which resulted in photoinhibition and increased ROS accumulation. The ROS accumulation was due to the decreased photoprotective mechanism of non-photochemical quenching (NPQ) and to the donor-side photoinhibition. Despite ROS accumulation, ZnO@OAm NPs decreased the excess excitation energy of the PSII, indicating improved PSII efficiency. Therefore, synthesized ZnO@OAm NPs can potentially be used as photosynthetic biostimulants for enhancing crop yields after being tested on other plant species.
Super High-Concentration Si and N Doping of CVD Diamond Film by Thermal Decomposition of Silicon Nitride Substrate
Authors: Yang Yong , Wang Yongnian , Yan Huaxin , Cao Chenyi , Chen Naichao
Published: August 2023

The high-concentration N doping of diamond film is still a challenge since nitrogen is limited during diamond growth. In this work, a novel method combined with the thermal decomposition of silicon nitride was proposed to form the activated N and Si components in the reactor gas that surrounded the substrate, with which the high-concentration N and Si doping of diamond film was performed. Meanwhile, graphene oxide (GO) particles were also employed as an adsorbent to further increase the concentration of the N element in diamond film by capturing the more decomposed N components. All the as-deposited diamond films were characterized by scanning electron microscopy, energy dispersive spectroscopy, Raman spectroscopy, and X-ray photoelectron spectroscopy. For the pure diamond film with a growth time of 0.5 h, the N and Si concentrations were 20.78 and 41.21 at%, respectively. For the GO-diamond film, they reached 47.47 and 21.66 at%, which set a new record for super high-concentration N doping of diamond film. Hence, thermal decomposition for the substrate can be regarded as a potential and alternative method to deposit the chemical vapor deposition (CVD) diamond film with high-concentration N, which be favorable for the widespread application of diamond in the electric field.
Effect of Sodium Hydroxide and Tripolyphosphate on Curcumin Release from Chitosan-Based Macroparticles
Authors: Pistone Alessandro , de Gaetano Annamaria , Piperopoulos Elpida , Abate Chiara
Published: August 2023

This work deals with the synthesis of bare and curcumin (CUR)-loaded chitosan (CS)-based macroparticles by ionic gelation using sodium hydroxide (NaOH) or sodium tripolyphosphate (TPP). The resulting spherical-shaped macroparticles were studied using various characterization techniques, Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR), Thermogravimetric Analysis (TGA), and Differential Scanning Calorimetry (DSC). The release of CUR from the CS-based particles with respect to time was analyzed, and the encapsulation efficiency and degree of swelling were studied. All formulations showed excellent CUR trapping efficiency, exceeding 90%. In particular, the TPP-crosslinked macrobeads released 34 wt% of the charged CUR within minutes, while the remaining 66 wt% was released slowly. The results indicate that the correct choice of gelling agent and its concentration leads to spherical particles capable of encapsulating CUR and releasing it in a wide range of kinetics so that macrospheres can be used in different applications.
Effect of the Sintering Mechanism on the Crystallization Kinetics of Geopolymer-Based Ceramics
Authors: Mustapa Nur Bahijah , Ahmad Romisuhani , Al Bakri Abdullah Mohd Mustafa , Ibrahim Wan Mastura Wan , Sandu Andrei Victor , Nemes Ovidiu , Vizureanu Petrica , Kartikowati Christina W. , Risdanareni Puput
Published: August 2023

This research aims to study the effects of the sintering mechanism on the crystallization kinetics when the geopolymer is sintered at different temperatures: 200 °C, 400 °C, 600 °C, 800 °C, 1000 °C, and 1200 °C for a 3 h soaking time with a heating rate of 5 °C/min. The geopolymer is made up of kaolin and sodium silicate as the precursor and an alkali activator, respectively. Characterization of the nepheline produced was carried out using XRF to observe the chemical composition of the geopolymer ceramics. The microstructures and the phase characterization were determined by using SEM and XRD, respectively. The SEM micrograph showed the microstructural development of the geopolymer ceramics as well as identifying reacted/unreacted regions, porosity, and cracks. The maximum flexural strength of 78.92 MPa was achieved by geopolymer sintered at 1200 °C while the minimum was at 200 °C; 7.18 MPa. The result indicates that the flexural strength increased alongside the increment in the sintering temperature of the geopolymer ceramics. This result is supported by the data from the SEM micrograph, where at the temperature of 1000 °C, the matrix structure of geopolymer-based ceramics starts to become dense with the appearance of pores.
Silk Fibroin/ZnO Coated TiO2 Nanotubes for Improved Antimicrobial Effect of Ti Dental Implants
Authors: Păun Angela Gabriela , Dumitriu Cristina , Ungureanu Camelia , Popescu Simona
Published: August 2023

The aim of the present research is to develop a novel hybrid coating for a Ti dental implant that combines nature-inspired biomimetic polymers and TiO2 nanostructures with an entrapped ZnO antimicrobial agent. ZnO was used in other studies to cover the surface of Ti or Ti–Zr to reduce the need of clinical antibiotics, prevent the onset of peri-implantitis, and increase the success rate of oral clinical implantation. We developed an original coating that represents a promising approach in clinical dentistry. The titanium surface was first anodized to obtain TiO2 nanotubes (NT). Subsequently, on the NT surface, silk fibroin isolated from Bombyx mori cocoons was deposited as nanofibers using the electrospun technique. For an improved antibacterial effect, ZnO nanoparticles were incorporated in this biopolymer using three different methods. The surface properties of the newly created coatings were assessed to establish how they are influenced by the most important features: morphology, wettability, topography. The evaluation of stability by electrochemical methods in simulated physiological solutions was discussed more in detail, considering that it could bring necessary information related to the behavior of the implant material. All samples had improved roughness and hydrophilicity, as well as corrosion stability (with protection efficiency over 80%). The antibacterial test shows that the functional hybrid coating has good antibacterial activity because it can inhibit the proliferation of Staphylococcus aureus up to 53% and Enterococcus faecalis up to 55%. All Ti samples with the modified surface have proven superior properties compared with unmodified TiNT, which proved that they have the potential to be used as implant material in dentistry.
Experimental Study on the Interface Characteristics of Reinforced Crushed Rock Cushion Layer Based on Direct Shear Tests
Authors: Wang Liangliang , Zhu Qianlong , Jia Yan , Li Hu
Published: August 2023

Through indoor large-scale direct shear tests, the interface characteristics of the crushed rock cushions layer reinforced with ParaLink geogrid were studied. The test results indicate that the shear strength of the crushed rock aggregate and the interface strength parameters have a non-linear relationship with the normal stress. The addition of the geogrid reduces the shear strength of the crushed rock aggregate and the interface strength parameters, which is mainly due to the relatively large size, small thickness, and high smoothness of the geogrid. The reinforced geogrid has a significant impact on the deformation and fragmentation characteristics of the crushed rock aggregate. It effectively suppresses the shear contraction and shear dilation effects of the crushed rock aggregate, reducing its peak compression and peak dilation angle. Furthermore, it inhibits the tendency of particle fragmentation in the crushed rock aggregate.
Preparation of Denitrification Materials with Nickel Slag for Nitric Oxide Decomposition in Cement Kilns
Authors: Gan Yanling , Dai Wenjing , Huang Pingli , Zhang Boge , Cui Suping
Published: August 2023

NOx emission from the cement industry have received much attention. In order to reduce the NOx emission in cement kilns, nickel slag was used to prepare the non-ammonia denitrification material, and a denitrification mechanism was proposed in this study. The results showed that the denitrification material prepared at pH 7 exhibited the best denitrification performance. At low temperature, the highest denitrification performance was achieved between 200 and 300 °C with a NO decomposition rate of approximately 40%. Then, the NO decomposition rate increased as the temperature increased, reaching over 95% above 700 °C. The physicochemical characteristics showed that the material had the highest specific surface area and the highest relative Fe content, which benefited the denitrification performance. The divalent iron of the denitrification material was considered the active site for the reaction, and trivalent iron was not conducive to denitrification performance at a low temperature range. After the denitrification reaction, the Fe3+/Fe2+ increased from 0.89 to 1.31. The proposed denitrification mechanism was the redox process between divalent iron and trivalent iron. This study not only recycles industrial waste to reduce solid waste pollution but also efficiently removes nitrogen oxides from cement kilns without ammonia.
Effects of V-N Microalloying on Low-Cycle Fatigue Property in the Welded Joints of Constructional Steel
Authors: Cui Kaiyu , Yang Haifeng , Li Zhengrong , Wang Guodong , Zhao Hongyun , Li Yuxuan
Published: August 2023

Low-cycle fatigue testing was carried out for the welded joints of constructional steels containing 0% V + 0.0021% N and 0.10% V + 0.0078% N, and the effects of V-N microalloying on the low-cycle fatigue property of the welded joints were investigated. The results showed that when the total strain amplitudes were 1.2%, 1.4% and 1.6%, the mean low-cycle fatigue lives of the welded joints of steel containing 0.10% V + 0.0078% N were 5050, 2372 and 1535 cycles, respectively, which were significantly higher than those of the welded joints of steel containing 0% V + 0.0021% N; however, when the total strain amplitudes increased to 1.8% and 2.0%, the mean low-cycle fatigue lives of the welded joints of steel containing 0.10% V + 0.0078% N were 575 and 367 cycles, respectively, which were gradually lower than those of the welded joints of steel containing 0% V + 0.0021% N. The reasons causing the difference of low-cycle fatigue life were explained by the dislocation structure and precipitates in the welding heat-affected zone, plastic strain energy density of the welded joints, and fatigue fracture morphology. When the low-cycle fatigue life is between 100 and 200 cycles, the cyclic toughness of the welded joint of steel containing 0.10% V + 0.0078% N is between 57.48 and 78.22 J/cm3, which is higher than that of the welded joint of steel containing 0% V + 0.0021% N, indicating that the welded joint of steel containing 0.10% V + 0.0078% N is able to absorb more energy in a seismic condition, therefore possessing better seismic resistance.
Finishing Additively Manufactured Ti6Al4V Alloy with Low-Energy Electrical Discharges
Authors: Oniszczuk-Świercz Dorota , Kopytowski Adrian , Nowicki Rafał , Świercz Rafał
Published: August 2023

Additive manufacturing has garnered significant interest in various industries due to its flexibility and capability to produce parts with complex shapes. However, issues related to surface quality, such as roughness and microstructural defects, necessitate the use of post-processing techniques to achieve the desired properties. Ti6Al4V alloy, produced additively, was finished using low-energy discharges, and the new surface integrity properties resulting from the induced heat energy were investigated. To further understand the influence of discharge energy on the formation of the new layer, roughness parameters and power spectral density were used to characterize the surface topography. SEM and EDS analyses were performed to examine the morphology and microstructural defects such as microcracks. The results indicate that the heat energy induced by the discharge improved the properties of the surface. SEM analysis revealed that the new layer was characterized by a reduction in defects such as unmelted particles, the balling effect, and microcracks. At the lowest investigated discharge energy of E = 0.21 mJ, surface roughness, Sa, was reduced by about 69%, which is equal to about 2 μm, accompanied by a significant decrease in microcracks. EDS analysis indicated that the diffusion of copper and zinc from the electrode to the top surface was related to the discharge energy. Furthermore, prediction models of the influence of wire electrical discharge polishing parameters, including discharge energy, wire speed, and time interval, on the surface roughness and material removal rate (MRR) were developed using the response surface methodology.
Buckling and Free Vibration Analyses of Various Nanoparticle Reinforced Concrete Beams Resting on Multi-Parameter Elastic Foundations
Authors: Dine Elhennani Soumia , Harrat Zouaoui R. , Chatbi Mohammed , Belbachir Asma , Krour Baghdad , Işık Ercan , Harirchian Ehsan , Bouremana Mohamed , Bachir Bouiadjra Mohamed
Published: August 2023

Given their considerable specific surface area and amorphous characteristics, nanoparticles exhibit excellent pozzolanic activity, and when undergoing a reaction with calcium hydroxide, this leads to the generation of a denser matrix by promoting the formation of a greater amount of C-S-H gel, thereby enhancing the strength and durability of the concrete and fortifying the overall structure. Indeed, the present study investigates a comparative study of the buckling and free vibration analyses of concrete beams reinforced with various types of nanoparticles. For its simplicity and accuracy, a higher-order shear deformation theory will be used to analytically model the reinforced concrete beam. Furthermore, the powerful Eshelby’s model is used to derive the equivalent nanocomposite properties. The soil medium is simulated with Pasternak elastic foundation, including a shear layer, and Winkler’s spring, interlinked with a Kerr foundation. The motion equations are derived using Hamilton’s principle. Moreover, based on Navier’s analytical methods, the closed-form solutions of simply supported beams have been obtained. Different parameters, such as type and volume percent of nanoparticles, geometrical parameters, choice of theory and soil medium, on the buckling and dynamic behavior of the beam, are exercised and shown. The major findings of this work indicate that the use of nanoparticles in concretes increases better mechanical resistance and amplifies the natural frequencies. In addition, the elastic foundation has a significant impact on the buckling and vibration performances of concrete beams.
Aging Behavior and Mechanism Evolution of Nano-Al2O3/Styrene-Butadiene-Styrene-Modified Asphalt under Thermal-Oxidative Aging
Authors: Ji Zhiyuan , Wu Xing , Zhang Yao , Milani Gabriele
Published: August 2023

The goal of this paper is to analyze the aging behavior and the mechanism evolution of nano-Al2O3 (NA)-reinforced styrene-butadiene-styrene (SBS) asphalt under different thermal-oxidative aging conditions. First, NA/SBS-modified asphalt and SBS-modified asphalt with different aging levels were prepared. Second, the viscosity and high temperature rheological performance of the specimens were tested and the property-related aging indexes were calculated and compared. Third, a Fourier transform infrared (FTIR) test of the specimen was conducted and the chemical group-related aging indexes were calculated and analyzed. Fourth, gel permeation chromatography (GPC) was used to analyze the molecular weight of the specimens under different aging levels. Then, an atomic force microscope (AFM) was adopted to analyze the microsurface morphology of different specimens. Finally, correlation analysis between property-related indexes and chemical group indexes was conducted. The results show that NA can enhance the thermal-oxidative aging resistance of SBS asphalt. NA can inhibit the increase in sulfoxide groups and the degradation of the SBS polymer with the increase in aging. NA can slow down the formation of large molecule during the aging process. The degree of change in both the bee structures and micromorphological roughness of NA/SBS asphalt is lower than that of SBS asphalt under different aging levels.
Advances in Dental Implants, Tissue Engineering and Prosthetic Materials
Authors: Tatullo Marco , Ambrogio Giuseppina , Sammartino Gilberto
Published: August 2023

Scientific research has achieved numerous milestones in the field of materials applied to medicine for biomedical prosthetics [...]
The Influence of Heat Aging Treatments on the Cavitation Erosion Behavior of a Type 6082 Aluminum Alloy
Authors: Bordeasu Ilare , Ghiban Brândușa , Micu Lavinia Madalina , Luca Alexandru Nicolae , Demian Alin Mihai , Istrate Dionisie
Published: August 2023

It is known that a number of parts that operate in liquid media, such as the propellers of motorboats and pleasure river vessels, as well as the rotors of household pumps and the radiators and pumps in the cooling system of motor vehicles are made, as a rule, of aluminum-based alloy. Research during maintenance leads to the conclusion that, in certain operating conditions, due to the turbulent character of the flow, with pressure drops to below the vaporization level, it inevitably reaches the threshold of cavitation, which manifests itself through its effects, especially through erosion. To increase the lifetime, these alloys are currently subjected to techniques to improve the structure’s resistance to the cyclic stresses of cavitational microjets. Among these techniques are volumetric heat treatments, which lead to changes in the microstructure and mechanical property values, with an effect on the behavior and resistance to cavitation erosion. This paper studies the influence of heat aging treatments on the cavitation erosion behavior of an aluminum alloy type 6082, in the cast state. The heat treatments applied were 140 °C/1 h, 12 h, 24 h and 180 °C/1 h, 12 h, 24 h. The MDEmax and MDERs parameters were determined and a correlation could be made between the values of the mechanical-resilient characteristics and the resistance to cavitation erosion in the case of aluminum alloy 6082.
Understanding the Microstructure Evolution of 8Cr4Mo4V Steel under High-Dose-Rate Ion Implantation
Authors: Miao Bin , Zhang Jinming , Guo Jiaxu , Ma Xinxin , Wang Liqin , Zhang Xinghong
Published: August 2023

In this study, the effect of microstructure under various dose rates of plasma immersion ion implantation on 8Cr4Mo4V steel has been investigated for crystallite size, lattice strain and dislocation density. The phase composition and structure parameters including crystallite size, dislocation density and lattice strain have been investigated by X-ray diffraction (XRD) measurements and determined from Scherrer’s equation and three different Williamson–Hall (W-H) methods. The obtained results reveal that a refined crystallite size, enlarged microstrain and increased dislocation density can be obtained for the 8Cr4Mo4V steel treated by different dose rates of ion implantation. Compared to the crystallite size (15.95 nm), microstrain (5.69 × 10−3) and dislocation density (8.48 × 1015) of the dose rate of 2.60 × 1017 ions/cm2·h, the finest grain size, the largest microstrain and the highest dislocation density of implanted samples can be achieved when the dose rate rises to 5.18 × 1017 ions/cm2·h, the effect of refining is 26.13%, and the increment of microstrain and dislocation density are 26.3% and 45.6%, respectively. Moreover, the Williamson–Hall plots are fitted linearly by taking βcosθ along the y-axis and 4sinθ or 4sinθ/Yhkl or 4sinθ(2/Yhkl)1/2 along the x-axis. In all of the W-H graphs, it can be observed that some of the implanted samples present a negative and a positive slope; a negative and a positive slope in the plot indicate the presence of compressive and tensile strain in the material.
High-Temperature Tensile Behaviour of GTAW Joints of P92 Steel and Alloy 617 for Two Different Fillers
Authors: Kumar Amit , Sirohi Sachin , Pandey Shailesh Mani , Kumar Pradeep , Fydrych Dariusz , Pandey Chandan
Published: August 2023

This study explores the high-temperature (HT) tensile rupture characteristics of a dissimilar gas-tungsten-arc-welded (GTAW) joint between P92 steel and Alloy 617, fabricated using ER62S-B9 and ERNiCrCoMo-1 fillers. The high-temperature tensile tests were performed at elevated temperatures of 550 °C and 650 °C. An optical microscope (OM) and a field emission scanning electron microscope (FESEM) were utilized to characterize the joint. The high-temperature test results indicated that the specimen failed at the P92 base metal/intercritical heat-affected zone (ICHAZ) rather than the weld metal for the ERNiCrCoMo-1(IN617) filler. This finding confirmed the suitability of the joint for use in the Indian advanced ultra-supercritical (A-USC) program. The fracture surface morphology and presence of precipitates were analysed using an SEM equipped with energy dispersive spectroscopy (EDS). The appearance of the dimples and voids confirmed that both welded fillers underwent ductile–dominant fracture. EDS analysis revealed the presence of Cr-rich M23C6 phases, which was confirmed on the fracture surface of the ER62S-B9 weld (P92-weld). The hardness plot was analysed both in the as-welded condition and after the fracture.
SSDStacked-BLS with Extended Depth and Width: Infrared Fault Diagnosis of Rolling Bearings under Dual Feature Selection
Authors: Zhou Jianmin , Liu Lulu , Shen Xiwen
Published: August 2023

In fault diagnosis, broad learning systems (BLS) have been applied in recent years. However, the best fault diagnosis cannot be guaranteed by width node extension alone, so a stacked broad learning system (stacked BLS) was proposed. Most of the methods for choosing the number of depth layers used optimization algorithms that tend to increase computation time. In addition, the data under single feature selection are not sufficiently representative, and effective features are easily lost. To solve these problems, this article proposes an infrared fault diagnosis model for rolling bearings based on integration of principal component analysis and singular value decomposition (IPS) and the stacked BLS with self-selected depth model (SSDStacked-BLS). First, 72 second-order statistical features are extracted from the pre-processed infrared images of rolling bearings. Next, feature selection is performed using IPS. he IPS feature selection module consists of principal component analysis (PCA) and singular value decomposition (SVD). The feature selection is performed by PCA and SVD separately, which are then stitched together to form a new feature. This ensures a comprehensive coverage of infrared image features. Finally, the acquired features are input into SSDStacked-BLS. This model establishes a data storage group for the residual training characteristics of stacked BLS, adding one block at a time. The accuracy rate of each newly added block is output and saved to the data storage group. If the diagnostic rate fails to increase three consecutive times, the block stacking is stopped and the results are output. IPS-SSDStacked-BLS achieved an accuracy of 0.9667 in 0.1775 s. This is almost five times faster than stacked BLS optimized using the grid search method. Compared with the original BLS, its accuracy was 0.0445 higher and the time was approximated. Compared with IPS-SVM, IPS-RF, IPS-1DCNN and 2DCNN, IPS-SSDStacked-BLS was more advantageous in terms of accuracy and time consumption.
Anti-Hyperlipidemic Effect of Fucoidan Fractions Prepared from Iceland Brown Algae Ascophyllum nodosum in an Hyperlipidemic Mice Model
Authors: He Yunhai , Li Yutong , Shen Peili , Li Shangkun , Zhang Linsong , Wang Qiukuan , Ren Dandan , Liu Shu , Zhang Demeng , Zhou Hui
Published: August 2023

Ascophyllum nodosum, a brown algae abundantly found along the North Atlantic coast, is recognized for its high polysaccharide content. In this study, we investigated the anti-hyperlipidemic effect of fucoidans derived from A. nodosum, aiming to provide information for their potential application in anti-hyperlipidemic therapies and to explore comprehensive utilization of this Iceland brown seaweed. The crude fucoidan prepared from A. nodosum was separated using a diethylethanolamine column, resulting in two fucoidan fractions, AFC-1 and AFC-2. Both fractions were predominantly composed of fucose and xylose. AFC-1 exhibited a higher sulfate content of 27.8% compared to AFC-2 with 17.0%. AFC-2 was primarily sulfated at the hydroxy group of C2, whereas AFC-1 was sulfated at both the hydroxy groups of C2 and C4. To evaluate the anti-hyperlipidemic effect, a hyperlipidemia mouse model was established by feeding mice a high-fat diet. The effects of AFC-1, AFC-2, and the crude extract were investigated, with the drug atorvastatin used as a positive comparison. Among the different fucoidan fractions and doses, the high dose of AFC-2 administration demonstrated the most significant anti-hyperlipidemic effect across various aspects, including physiological parameters, blood glucose levels, lipid profile, histological analysis, and the activities of oxidative stress-related enzymes and lipoprotein-metabolism-related enzymes (p < 0.05 for the final body weight and p < 0.01 for the rest indicators, compared with the model group), and its effect is comparable to the atorvastatin administration. Furthermore, fucoidan administration resulted in a lower degree of loss in gut flora diversity compared to atorvastatin administration. These findings highlight the significant biomedical potential of fucoidans derived from A. nodosum as a promising therapeutic solution for hypolipidemia.
Tuning the Bioactive Properties of Dunaliella salina Water Extracts by Ultrasound-Assisted Extraction
Authors: Ferreira Joana P. A. , Grácio Madalena , Sousa Isabel , Pagarete António , Nunes M. Cristiana , Raymundo Anabela
Published: August 2023

(1) Background: Microalgae are promising feedstock for obtaining valuable bioactive compounds. To facilitate the release of these important biomolecules from microalgae, effective cell disruption is usually necessary, where the use of ultrasound has achieved considerable popularity as an alternative to conventional methods. (2) Methods: This paper aims to evaluate the use of ultrasound technology in water medium as a green technology to recover high added-value compounds from Dunaliella salina and improve its sensory profile towards a high level of incorporation into novel food products. (3) Results: Among the variables, the solid concentration and extraction time have the most significant impact on the process. For the extraction of protein, or fat, the most influential factor is the extraction time. Total polyphenols are only significantly affected by the extraction time. The antioxidant capacity is strongly affected by the solid to liquid ratio and, to a small extent, by the extraction time. Ultrasound-assisted extraction improves the overall odor/aroma of D. salina with good acceptability by the panelists. (4) Conclusions: The application of ultrasonic-assisted extraction demonstrates a positive overall effect on enhancing the sensory profile, particularly the odor of microalgal biomass, while the bioactive properties are preserved. Notably, the intense sea/fish odors are reduced, while earthy and citrus notes become more prominent, resulting in an improved overall sensory profile score. This is the first time, to our knowledge, that this innovative, green, and efficient technology has been used to upgrade the aroma profile of microalgae.
Dental Caries Prevention Knowledge, Attitudes, and Practice among Patients at a University Hospital in Guangzhou, China
Authors: Jiang Rui , Yu Jiali , Islam Rafiqul , Li Xiang , Nie Ermin
Published: August 2023

Background and Objectives: This study aimed to assess the knowledge, attitudes, and practice (KAP) of patients regarding dental caries prevention in a university hospital in Guangzhou, China. Materials and Methods: A hospital-based KAP survey was conducted in a cross-sectional manner at the First Affiliated Hospital in Guangzhou, China, from 1 September to 30 September 2022. Questionnaires were distributed to eligible patients, resulting in the participation of 251 individuals. The questionnaire consisted of five sections capturing socio-demographic data and exploring participants’ knowledge, attitudes, practice, and accurate preventive dental caries knowledge. Descriptive statistics and a generalized linear model with univariate tests were used for analysis. Results: The study results show that the knowledge score 7.97 (±0.91) and attitudes score 7.67 (±0.89) among the participants were good while the practice score was 6.80 (±0.81) moderate. The majority of participants identified tooth infections (81.3%), bacteria (92%), and sugar (89.2%) as the main causes of gum bleeding and tooth decay. Brushing (96%) and fluoride (80.5%) were also recognized as essential for preventing tooth decay. Of oral diseases, 94% were recognized as potentially affecting overall health. The vast majority ranging from 92.8% to 98%, believed that oral health is crucial to overall health and that regular check-ups and proper brushing habits are beneficial. There is a significant association of gender with age (p = 0.018), occupation (p = 0.050), lifestyle habit (p = 0.012), and knowledge score; whole education is significantly associated with practice score (p = 0.050). Conclusions: The majority of patients exhibited accurate knowledge and attitudes with moderate practice towards dental caries prevention, with socio-demographic factors playing a major role. However, effective implementation of dental health education programs across the healthcare system is still required to further enhance outcomes.
Intradiscal Condoliase Injection Therapy for Recurrent Lumbar Disc Herniation: Case Series and Literature Review
Authors: Fukui Hiroki , Kamei Naosuke , Fujiwara Yasushi , Nakamae Toshio , Ohta Ryo , Kotaka Shinji , Adachi Nobuo
Published: August 2023

Background and objectives: Although chemonucleolysis with condoliase for lumbar disc herniation (LDH) has become common, few reports have described its application in the treatment of recurrent LDH. Therefore, this study aimed to evaluate the safety and efficacy of condoliase treatment in six patients with recurrent LDH and review the available literature on condoliase treatment for LDH. Materials and Methods: Six patients (four men and two women; mean age, 64.7 years) with recurrent LDH who were treated with condoliase at our hospital between 2019 and 2022 were included. The clinical records and images of the patients were retrospectively evaluated. In addition, the available English literature on condoliase treatment for LDH was retrieved and reviewed. Results: Among the six patients included in the study, three showed >50% improvement in leg pain after treatment, which is a lower efficacy rate than that in previous reports. In addition, two patients required surgery after treatment, which is a higher rate than that in previous reports. The mean intervertebral disc height significantly decreased from 8.4 mm before treatment to 6.9 mm after treatment, consistent with the results of previous studies. None of the cases showed Modic type I changes on magnetic resonance imaging. Conclusions: Although the efficacy of condoliase treatment for recurrent LDH may be lower than that for primary LDH, this treatment was found to be safe and applicable for recurrent LDH.
Is the Small Ossicle of Type 1 Accessory Navicular a Cause of Foot Pain?—A Case Report
Authors: Yokoe Takuji , Uemichi Kazushi , Tajima Takuya , Chosa Etsuo
Published: August 2023

Background and objectives: An accessory navicular (AN) bone is often classified into types 1–3 according to the Veitch classification, and symptomatic type 1 patients usually receive non-surgical treatment. However, there are cases in which AN cannot be classified into one of these three types using this classification system, and the small ossicle of type 1 AN may not be the cause of foot pain. This report aimed to present a case of symptomatic type 1 AN that required surgical treatment without the excision of the small ossicle after long-term conservative treatment had failed. Case presentation: A 15-year-old girl who was diagnosed with symptomatic type 1 AN was referred to our department. Medial-side foot pain had prevented her from playing soccer well. She had been treated conservatively for type 1 AN for more than 12 months at several orthopedic clinics. Tenderness of the prominent navicular tubercle was identified, and computed tomography and magnetic resonance imaging findings suggested that the cause of her foot pain was derived from the prominent navicular tubercle not the small ossicle itself. Osteotomy of the prominent navicular tubercle with the advancement of the tibialis posterior tendon, without excision of the ossicle, was performed. At the 12-month follow-up examination, she was completely free from foot pain, and the patient-reported outcome measures were excellent. She now plays soccer at the pre-injury level. Conclusions: We report the case of a patient with symptomatic type 1 AN who underwent osteotomy of the prominent navicular tubercle with advancement of the tibialis posterior tendon, without excision of the ossicle, and who showed favorable short-term clinical outcomes. The evaluation of symptomatic patients with AN based on the Veitch classification alone may lead to inappropriate management. The small ossicle of type 1 AN was not the cause of foot pain in the present case.