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In this study, the corrosion behavior and microstructural transformations of 1000 series aluminum and copper tubes after an explosive welding process were investigated. Welding was performed with a fixed stand-off distance and various explosion thicknesses. Explosive welding was carried out using a consistent stand-off distance of 2 mm while varying the thickness of the explosive material of 60 mm (sample 1) and 80 mm (sample 2). The explosion velocity employed during the process was measured at 2504 m/s. Optical and electron microscopy images revealed that the thickness of the melting layer at the interface increases proportionally with the thickness of the explosive charge. Specifically, as the explosive thickness increased from 60 to 80 mm, the thickness of the melting layer increased as well. Also, the resuls of the potentiodynamic polarization test indicated a decrease in the corrosion potential from –670 mV (sample 1) to –665 mV (sample 2) as the explosive material thicknesses increased. At the same time, the corrosion current density rose from 52.34 µA/cm2 (sample 1) to 78.32 μA/cm2 (sample 2). An analysis of the Nyquist diagram for explosive welding samples revealed that the curve radius of sample 2 exceeded that of sample 1, suggesting a higher corrosion resistance in sample 1 compared to that in sample 2. [ABSTRACT FROM AUTHOR]

In this study, the effect of the compaction velocity as well as the size and volume content of the reinforcing particles on the thermal properties of Mg-B4C composites were evaluated. B4C reinforcing particles at various percentages (0, 5, 10%) and two sizes (micron-scale and nanoscale) were added to the magnesium matrix using a planetary ball mill and compacted at 450 °C and three different compaction velocities. The Instron device was utilized for the quasi-static compaction of the powder particles while a drop-hammer and a Split-Hopkinson bar were used for the dynamic compaction of composite powders at medium and high strain rates, respectively. The thermal behavior of the composites was studied by measuring their thermal conductivity and coefficient of thermal expansion. The results showed improvement in dimensional stability of the composites with increasing the volume percentage of the reinforcing particles. Higher compaction velocities led to higher thermal conductivity and coefficient of thermal expansion. Besides, further addition of the reinforcing particles to the matrix resulted in a decrease in the thermal properties. Magnesium samples reinforced with B4C nanoparticles exhibited superior thermal properties compared to those reinforced with micron-sized particles. [ABSTRACT FROM AUTHOR]

Envelopes with low thermal performance are common characteristics in European historic buildings, causing higher energy demand and insufficient thermal comfort. This paper presents the results of a study on indoor environmental quality (IEQ), with special focus on thermal comfort, in the historic City Hall of Gävle, Sweden, now used as an office building. There are two modern heat recovery ventilation systems with displacement ventilation supply devices. The district heating network heats the building via pre-heat supply air and radiators. Summer cooling comes from electric heat pump ejecting heat into the exhaust ventilation air. A building management system (BMS) controls the heating, ventilation and air-conditioning (HVAC) equipment. The methodology included on-site measurements, BMS data logging and evaluating the occupants' perception of a summer and a winter period indoor environment using a standardized questionnaire. In conclusion, indoor environmental quality in this historic building is unsatisfactory. Stuffy air, too high, too low and varying room temperatures, lighting problems and noise are constant issues. Although it is equipped with modern ventilation systems, there are still possibilities for improving thermal comfort by improved control strategies, since upgrading the building's envelope is not allowed according to the Swedish Building Regulations in historic buildings with heritage value. [ABSTRACT FROM AUTHOR]

Powder dynamic compaction is one of the new methods for the production of nanocomposites. In this paper, Al6061/SiCnp nanocomposite is compacted using warm dynamic compaction by simultaneous application of heat and dynamic compressive waves. A comparison between the results of this study and those reported in the literature confirms that the warm dynamic compaction methods are superior to cold dynamic and quasi-static compaction method in densification of nanocomposites especially for high volume fractions of nano particles reinforcement. Mechanical and microstructural characterization of the samples is carried out to investigate the effects of temperature and content level of reinforcement. The results indicate that the increase of nano reinforcement content in warm dynamic compaction leads to reduction of the relative density and increase of hardness and the compressive strength. Moreover, higher compaction temperatures result in enhanced density and lower hardness. It is shown that samples compacted using warm dynamic compaction exhibit lower spring back and ejection force and also the distribution of mechanical properties is significantly more homogeneous. Sensitivity analysis showed that temperature increase has the most effect on homogeneity improvement and reducing dimensional change. Microscopic analyses verified that higher compaction temperature leads to lower porosity and improved metal particle bonding. It seems that agglomeration of nanoparticles and destructive phenomena such as capping and delamination are the main reasons for loss of compressive strength at room temperature. These issues are resolved in warm dynamic compaction by increasing the compaction temperature which leads to better bonding between particles. [ABSTRACT FROM AUTHOR]

In this study, TiO2 and ZnO nanofilms were prepared by sol-gel spin-coating method. Nanofilms were characterized by X-ray Diffraction (XRD), Energy Dispersive Analysis of X-ray (EDX), Scanning Electron Microscopy (SEM) and Field Emission Scanning Electron Microscopy (FE-ESM). Structural and morphological properties of nanofilms were investigated. The average crystalline size of TiO2 and ZnO nanoparticles which were obtained from the ignition of sols were obtained 80 and 50 nm, respectively. The morphological properties of nanofilms showed that the TiO2/ZnO nanocomposite film was strongly related to the steps of coating. Also, photocatalytic degradation of methylene blue on the surface of these nanofilms under UV light irradiation was studied and results were compared to each other. [ABSTRACT FROM AUTHOR]

ZnO and Mn-ZnO nano powders were prepared by the sol-gel auto combustion method. The products were characterized by X-ray diffraction (XRD), energy dispersive analysis of X-ray (EDX) and scanning electron microscopy (SEM). Structural and morphological properties of nano particles were investigated and the average crystalline size of ZnO and Mn-doped ZnO was obtained 44 and 51 nm, respectively. Also, photo catalytic removal of Cibacen Turquoise Blue G dye from aqueous solution by using nano scale ZnO and Mn-ZnO powders under UV light irradiation was studied. The effect of initial dye concentrations and dosage of photo catalysts, were investigated in the photo destructive process. This is 57% of dye degraded by 0.02 mg of ZnO in 70 minutes. The degradation rate increase to 84% in the presence of 0.02 mg of Mn-ZnO in the same time. [ABSTRACT FROM AUTHOR]

The purposes of this study were to determine normal value of glycated hemoglobin in Persian cats and to investigate its relation to fasting plasma glucose. Blood samples were collected from 67 clinically healthy adult Persian cats (32 males and 35 females). After separation and washing of red blood cells, hemolysate was prepared and subjected to weak cation exchange chromatography for determination of glycosylated hemoglobin. Glucose was measured in fasting plasma samples (after 10-12 h of fasting) using glucose oxidase method. Glycosylated hemoglobin % in the studied cats was 1.56 ± 0.47 in males and 1.61 ± 0.52 in females. Fasting plasma glucoses were 88.3 ± 10.2 and 90.8 ± 11.5 mg/dl in males and females, respectively. Glycosylated hemoglobin % and plasma glucose strongly correlated together ( r = 0.79, p < 0.001). Three cats with persistent high fasting plasma glucose showing glycosylated hemoglobin percentage of 2.6, 2.8, and 2.9 % which exceeded the upper limit of the normal value obtained in this study were found. We concluded that glycosylated hemoglobin % is a good indicator of fasting plasma glucose, and its determination can be considered as a method for diabetes screening in Persian cats. Considering three cats with persistent high fasting plasma glucose and glycosylated hemoglobin percent, we concluded that glycosylated hemoglobin percent could be a good biochemical test for screening or diagnosis diabetes in cats. [ABSTRACT FROM AUTHOR]

Background and Objectives The specific activation of the immune system especially T lymphocytes has been a long-term goal of cancer immunotherapy. In an approach to induce the patient's own immune cells, chimeric antigen receptors (CAR) were used to activate cytotoxic T lymphocytes. The CAR consists of an antigen binding domain of antibody molecule linked through an extracellular linker to transmembrane and cytoplasmic domains of lymphocyte-triggering moieties. Materials and Methods In our research group, variable domains of heavy chain antibodies (VHH or nanobody) derived from camelids were used instead of the antigen-binding domain in chimeric receptors constructs. To obtain a stable and increased expression of VHH harboring CAR, the PhiC31 integrase system was used for CAR gene integration into the T-cell genome. Constructs expressing CAR and PhiC31 integrase were co-transfected into the Jurkat cell line and CAR expression was quantified after one day and 30 days after transfection by a semi-quantitative RT-PCR method. Results Our results on day 30 confirmed that co-transfection of PhiC31 integrase constructs and CAR expressing constructs resulted in stable and high expression of the receptors. Conclusions Based on our results, we conclude that PhiC31 integrase enzyme can be used for immunotherapy of cancer mediated by T cells expressing chimeric recetors. [ABSTRACT FROM AUTHOR]

Background: Pediculus capitis or head louse infestation affects millions of children worldwide, especially those in the 5-11 years age group. This study aimed to determine the prevalence of head pediculosis among school children in urban and rural areas of Fars Province, southern Iran. Methods: All school children of age 6-11 yr from both genders in all urban and rural areas of the province were screened for head louse infestation by examination of their hair and scalps. Parents of all infested children were also examined. The study was repeated in different seasons in the same areas. Moreover, infested children were treated with 5% permethrin shampoo and re-examined one week later for any relapse. Results: The general prevalence of head louse infestation in primary school students was 0.49% in autumn, 0.37% in winter and 0.20% in spring. In the mentioned seasons, the prevalence of P. capitis was higher among females and in rural areas (P=0.001). Although treatment with permethrin shampoo failed in females, it was successful in all infected males from both regions in autumn and spring and in males from urban areas in winter. Conclusion: Head louse infestation is uncommon among Fars Province school children in rural and urban areas and should not be considered a public health priority. However, due to the higher prevalence of pediculosis in low socioeconomic group and rural area in our region, it seems that health promotion, particularly early detection and effective management strategies should target this group in the province. [ABSTRACT FROM AUTHOR]

Bone scaffolds serve a crucial role in tissue engineering, particularly in facilitating bone regeneration where natural repair is insufficient. Despite advancements in the fabrication of polymeric bone scaffolds, the challenge remains to optimize their mechanical resilience. Specifically, research on the fatigue behaviour of polymeric bone scaffolds is scarce. This study investigates the influence of pore architecture on the mechanical performance of poly-lactic-acid (PLA) scaffolds under quasi-static and cyclic compression. PLA scaffolds with a 60% porosity were fabricated using extrusion-based 3D printing in various designs: Gyroid, Lidinoid, Fischer-Koch, IWP, and Voronoi. Results demonstrated that Gyroid scaffolds had the highest compressive strength (6.6 MPa), followed by Lidinoid, Fischer-Koch, IWP, and Voronoi designs. Increased strut thickness was linked to higher compressive strength. However, normalized fatigue resistance showed a different pattern. While scaffolds resisted fatigue cycles at low strain amplitudes, fatigue damage was observed at higher strains. Voronoi structures exhibited the highest normalized fatigue performance, enduring around 58,000 cycles at 85% strain amplitude, followed by Gyroid, Fischer-Koch, Lidinoid, and IWP structures. Enhanced fatigue performance in different topologies correlated with the minimum cross-sectional area of scaffolds. Given the importance of both static and fatigue strength, the Gyroid topology emerges as the superior choice overall.

The bacterium Burkholderia pseudomallei is the cause of melioidosis infectious disease. In this bacterium, the BLF1 protein wide inhibits the synthesis of proteins in human cells. This disease is reported to cause a death rate of 40% in some parts of the world. Currently, no effective vaccine is available against this bacterial infection. In this study, therefore, a Nano vaccine was synthesized based on the trimethyl chitosan (TMC) polymer containing the BLF1 recombinant protein, and its immunogenicity and protection in Syrian mice were evaluated by oral and subcutaneous injections. The BLF1 recombinant protein expression was induced in Escherichia coli Bl21 (DE3) and purified by the affinity chromatography technique. Recombinant protein-containing nanoparticles (NPs) were then synthesized by the ionotropic gelation method. After oral and subcutaneous injections, antibody titration was assessed by the indirect ELISA assay. Finally, murine groups were challenged using the BLF1 toxin. The results indicated that the immune system showed more antibody titration in subcutaneous injection than in the oral form. However, the results were reversed in the challenge results, and the survival rate was more significant in the oral injection., (Copyright © 2024. Published by Elsevier Inc.)

Bone scaffolds play a crucial role in bone tissue engineering by providing mechanical support for the growth of new tissue while enduring static and fatigue loads. Although polymers possess favourable characteristics such as adjustable degradation rate, tissue-compatible stiffness, ease of fabrication, and low toxicity, their relatively low mechanical strength has limited their use in load-bearing applications. While numerous studies have focused on assessing the static strength of polymeric scaffolds, little research has been conducted on their fatigue properties. The current review presents a comprehensive study on the fatigue behaviour of polymeric bone scaffolds. The fatigue failure in polymeric scaffolds is discussed and the impact of material properties, topological features, loading conditions, and environmental factors are also examined. The present review also provides insight into the fatigue damage evolution within polymeric scaffolds, drawing comparisons to the behaviour observed in natural bone. Additionally, the effect of polymer microstructure, incorporating reinforcing materials, the introduction of topological features, and hydrodynamic/corrosive impact of body fluids in the fatigue life of scaffolds are discussed. Understanding these parameters is crucial for enhancing the fatigue resistance of polymeric scaffolds and holds promise for expanding their application in clinical settings as structural biomaterials. STATEMENT OF SIGNIFICANCE: Polymers have promising advantages for bone tissue engineering, including adjustable degradation rates, compatibility with native bone stiffness, ease of fabrication, and low toxicity. However, their limited mechanical strength has hindered their use in load-bearing scaffolds for clinical applications. While prior studies have addressed static behaviour of polymeric scaffolds, a comprehensive review of their fatigue performance is lacking. This review explores this gap, addressing fatigue characteristics, failure mechanisms, and the influence of parameters like material properties, topological features, loading conditions, and environmental factors. It also examines microstructure, reinforcement materials, pore architectures, body fluids, and tissue ingrowth effects on fatigue behaviour. A significant emphasis is placed on understanding fatigue damage progression in polymeric scaffolds, comparing it to natural bone behaviour., Competing Interests: Declaration of Competing Interest I hereby declare this research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. The authors declare no conflict of interest and the manuscript has been read and approved by all of them. The contents of the paper have not been published previously and is not under consideration by another journal., (Copyright © 2023 The Author(s). Published by Elsevier Ltd.. All rights reserved.)