Impact of Denture Use on Oral Health-Related Quality of Life in Yemeni Patients: A Cross-Sectional Analysis.

BACKGROUND We used the 14-item Oral Health Impact Profile-14 (OHIP-14) questionnaire to evaluate the association between sociodemographic variables and oral health-related quality of life in 241 wearers of removable partial or complete dentures attending a single center in Yemen. MATERIAL AND METHODS A total of 241 partial dentures (PD) and complete dentures (CD) wearers were enrolled from the Department of Prosthodontics at the Faculty of Dentistry, Sana'a University, and the University of Science and Technology. Data were collected before the commencement of denture wearing and after 3-6 months of denture use. The questionnaire consisted of sociodemographic information and denture type, and another for the OHIP to assess oral health-related quality of life (OHRQoL), oral health impact profile scale comprises 7 subscales, each evaluating different aspects of oral health and functionality. Descriptive statistics were calculated for participants. Independent t tests were performed to compare different patient groups, focusing on PD and CD wearers. Paired-sample t tests were used to examine changes within patient groups before and after removable denture use. RESULTS Among all participants, 67.6% were male, wearers of CDs were 74.6% male, PDs were 58.3%, and was consistent for CD (71.0%) and PD (72.8%) wearers. The wearing prostheses significantly impacted the OHRQoL of patients using both PDs and CDs (P<0.01). Among CD wearers, 4 of these subscales (3-6) were statistically significant, but the handicaps subscale showed evident reductions in physical pain after treatment among PD wearers. CONCLUSIONS Wearing dentures positively affects the OHRQoL of patients, influencing various aspects of their health, including functional, physical, psychological, and social well-being.

Investigating the influence of molybdenum disulfide quantum dots coated with DSPE-PEG-TPP on molecular structures of liver lipids and proteins: An in vivo study.

Molybdenum disulfide (MoS2) quantum dots (QDs) based therapeutic approaches hold great promise for biomedical applications, necessitating a thorough evaluation of their potential effects on biological systems. In this study, we systematically investigated the impact of MoS2 QDs coated with 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[amino(polyethyleneglycol)-2000](DPSE-PEG) linked with (3-carboxypropyl)triphenyl-phosphonium-bromide (TPP) on molecular structures of hepatic tissue lipids and proteins through a multifaceted analysis. The DSPE-PEG-TPP-MoS2 QDs were prepared and administered to the mice daily for 7 weeks. Liver tissues were subjected to a comprehensive examination using various techniques, including Fourier-transform infrared (FTIR) spectroscopy, UV-vis spectroscopy, and liver function tests. FTIR revealed subtle changes in the lipid composition of liver tissues, indicating potential modifications in the cell membrane structure. Also, the (CH stretching and amides I and II regions) analysis unveiled tiny alterations in lipid chain length and fluidity without changes in the protein structures, suggesting a minor influence of DSPE-PEG-TPP-MoS2 QDs on the liver's cellular membrane and no effect on the protein structures. Further scrutiny using UV-vis spectroscopy demonstrated that DSPE-PEG-TPP-MoS2 QDs had no discernible impact on the absorbance intensities of aromatic amino acids and the Soret band. This observation implies that the treatment with SPE-PEG-TPP-MoS2 QDs did not induce significant alterations in helical conformation or the microenvironment surrounding prosthetic groups in liver tissues. The liver function tests, including ALP, ALT, AST, and BIL levels, revealed no statistically significant changes in these key biomarkers despite minor fluctuations in their values, indicating a lack of significant liver dysfunction. This study provides a detailed understanding of the effects of DSPE-PEG-TPP-MoS2 QDs on hepatic lipids and proteins, offering valuable insights into the biocompatibility and limited impact on the molecular and functional aspects of the liver tissue. These findings could be essential for the application of MoS2 QDs-based therapies.

CoFe2O4/PANI/MWCNTs ternary hybrid composites. Synthesis, characterization, the effect of MWCNTs ratio and dye removal capability.

We have synthesized cobalt ferrite (CoFe2O4) using the sucrose auto-combustion method and subsequently employed the in situ polymerization technique to fabricate ternary composites comprising CoFe2O4, polyaniline (PANI), and multi-walled carbon nanotubes (MWCNTs). In this novel investigation, we explored the influence of varying MWCNTs ratios on these composites' structural, magnetic, thermal, and electrical properties. The crystal structures of the synthesized composites were analyzed using X-ray diffraction (XRD), while Fourier transform infrared (FT-IR) spectroscopy revealed changes in bonding patterns, including the disappearance of ferrite bonds and the emergence of new ones. Transmission electron microscopy (TEM) images illustrated a complete coating of PANI on both MWCNTs and CoFe2O4 particles, resulting in a substantial reduction in magnetization compared to pure CoFe2O4 ferrite due to PANI's nonmagnetic nature. Vibrating sample magnetometer (VSM) measurements confirmed this reduction, indicating a decrease to 7.3 emu.g-1. Thermal analysis demonstrated an enhancement in thermal stability with increasing MWCNTs content, as evidenced by an increase in the temperature equivalent for half decomposition (T50) from 486 to 522 °C for composites with 40% MWCNTs. Moreover, the electrical conductivity showed a corresponding rise with MWCNTs content, increasing from 3.1 × 10-3 Ω-1.cm-1 to 2.2 × 10-2 Ω-1.cm-1, possibly indicating charge transfer from PANI to MWCNTs. To assess practical applications, we investigated the ability of the composite with 40% MWCNTs to remove phenol red (PR) dye from aqueous solutions. Through a systematic study of adsorption parameters and kinetics, we determined optimal conditions for effective dye removal and elucidated the underlying adsorption mechanism. Our results demonstrated the composite's efficiency in dye removal, with a 6.4 mg·g-1 capacity for PR dye, highlighting its potential for environmental remediation efforts.

The role of MoS2 QDs coated with DSPE-PEG-TPP in the protection of protein secondary structure of the brain tissues in an Alzheimer's disease model.

In this investigation, we have explored the protective capacity of MoS2 QDs coated with 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[amino(polyethyleneglycol) -2000] (DSPE-PEG) linked with (3-carboxypropyl) triphenylphosphonium-bromide (TPP), on the secondary structure of proteins in Alzheimer's disease (AD)-affected brain tissues. Using a cohort of fifteen male SWR/J mice, we establish three groups: a control group, a second group induced with AD through daily doses of AlCl3 and D-galactose for 49 consecutive days, and a third group receiving the same AD-inducing doses but treated with DSPE-PEG-TPP-MoS2 QDs. Brain tissues are meticulously separated from the skull, and their molecular structures are analyzed via FTIR spectroscopy. Employing the curve fitting method on the amide I peak, we delve into the nuances of protein secondary structure. The FTIR analysis reveals a marked increase in ß-sheet structures and a concurrent decline in turn and α-helix structures in the AD group in comparison to the control group. Notably, no statistically significant differences emerge between the treated and control mice. Furthermore, multivariate analysis of the FTIR spectral region, encompassing protein amide molecular structures, underscores a remarkable similarity between the treated and normal mice. This study elucidates the potential of DSPE-PEG-TPP-MoS2 QDs in shielding brain tissue proteins against the pathogenic influences of AD.

Fabrication and Characterization of Oxygen-Generating Polylactic Acid/Calcium Peroxide Composite Filaments for Bone Scaffolds.

The latest advancements in bone scaffold technology have introduced novel biomaterials that have the ability to generate oxygen when implanted, improving cell viability and tissue maturation. In this paper, we present a new oxygen-generating polylactic acid (PLA)/calcium peroxide (CPO) composite filament that can be used in 3D printing scaffolds. The composite material was prepared using a wet solution mixing method, followed by drying and hot melting extrusion. The concentration of calcium peroxide in the composite varied from 0% to 9%. The prepared filaments were characterized in terms of the presence of calcium peroxide, the generated oxygen release, porosity, and antibacterial activities. Data obtained from scanning electron microscopy and X-ray diffraction showed that the calcium peroxide remained stable in the composite. The maximum calcium and oxygen release was observed in filaments with a 6% calcium peroxide content. In addition, bacterial inhibition was achieved in samples with a calcium peroxide content of 6% or higher. These results indicate that an optimized PLA filament with a 6% calcium peroxide content holds great promise for improving bone generation through bone cell oxygenation and resistance to bacterial infections.

Epoxy Flooring/Oil Fly Ash as a Multifunctional Composite with Enhanced Mechanical Performance for Neutron Shielding and Chemical-Resistance Applications.

Heavy-oil fly ash (HOFA) is a graphitic carbon powder extracted in vast amounts as a waste material from burning crude oil in power plants. This HOFA has attractive structural properties besides its high amount of pure carbon (∼90 wt %). This powder exists in spherical, highly porous micron-sized particles, which implies its great potential as a mechanical reinforcement for different polymers. In this work, HOFA has been utilized to enhance the mechanical properties of epoxy flooring at HOFA weight fractions of 0, 1, 1.6, and 3.2 wt %. The obtained results revealed that the prepared epoxy-flooring/HOFA composites at a HOFA content of 1.6 wt % showed significant mechanical improvements compared with the pristine polymer. The tensile strength and Young's module values were enhanced by ∼17 and 11%, respectively. Furthermore, the neutron-shielding performance was investigated. The composite with 1.6 wt % showed better neutron attenuation and lower transmittance than the pristine epoxy. The chemical resistance was also extensively studied against sodium hydroxide, nitric acid, and sulfuric acid. The changes in morphology, chemical elements, mass, volume, and molecular structures were investigated rigorously for pristine epoxy and its composite with HOFA at 1.6 wt %. After exposure to these chemicals for 21 days, the tested properties of the epoxy-flooring/HOFA composite showed better chemical resistance than that of the pristine epoxy. Where the epoxy-flooring/HOFA composite showed a surface with low cracks and blistering, it showed lesser changes in mass and volume and fewer molecular structure changes. These results indicated that it is possible to use this multifunctional composite for several applications, including the petrochemical industry, radiation shielding, construction, and automobiles.

Oil fly ash as a promise larvicide against the Aedes aegypti mosquitoes.

Two environmental problems exist in some tropical and subtropical areas: the Aedes aegypti (L.) (Ae. aegypti) mosquito and thousands of tons of heavy oil fly ash (HOFA) from power plants. Herein, micro/nanoparticles of HOFA have been utilized as a larvicide against Ae. aegypti without any chemical or biological additive materials. We estimated the accumulative mortalities in the third instar after 24/48 h (h). We found that after 24 h of exposing the larvae to the HOFA microsized, the LC50 and LC90 were 0.55 and 4.87 mg/ml, respectively, while they were 0.10 and 0.36 mg/ml after 48 h. At the same time, the LC50 and LC90 were respectively 0.12 and 0.60 mg/ml after 24 h exposing the larvae to the HOFA nanosized, and they were 0.06 and 0.23 mg/ml after 48 h. These results showed that the HOFA nanoparticles as larvicides were more effective than HOFA microparticles. The microscopy images also revealed deformations such as pigmentations, segment shrinkage, larva swelling, segment body contraction, siphon swelling, intermediate stage, head deformations, and thorax swelling in the larvae exposed to the HOFA. These deformations could indicate alterations in the hormones that control the biochemistry of the larvae body. The findings of this study could suggest the possibility of using HOFA, particularly in nanosized, as a promising larvicide against the Ae. aegypti mosquito.

Analysis of the Facial Measurements and Dental Arch Dimensions for the Construction of Dental Prostheses among Adult Yemenis.

AIM: To investigate the dental arch dimension (width, length, and height) and facial measurements including inner-canthal width (ICW), bizygomatic width (BZW), inter-alar width (IAW), and mouth width (MW), and to assess the correlation between these facial measurements and dental arch width (canine width [CW], inter-first premolar width [I1PW], and inter-first molar width [I1MW]), to establish a preliminary reference for artificial teeth selection in Yemeni adult. MATERIALS AND METHODS: The study included 80 individuals (40 males and 40 females) with symmetrical faces and normal class I occlusion ranging in age from 20 to 35. Maxillary and mandibular stone casts were made for each individual. The dimensions of dental casts and facial measurements, including ICW, BZW, IAW, and MW, were assessed using a digital caliper. The collected data were analyzed by using the SPSS software program. The descriptive statistics for each measurement were made. Differences between males and females were tested using an independent-sample t-test with p-values below 0.05 considered significant. Pearson correlation coefficient between facial measurements and dental arch width was also done. RESULTS: Most dental arch dimensions and facial measurements exhibited larger mean values in the male than in the female group, with the greatest significant difference in the maxillary dental arch width and the lowest in mandibular dental arch length. A highly significant correlation is observed between ICW and maxillary canine width (CW) (r = 0.318, p = 0.004). In contrast, no significant correlation between dental arch width and BZW, IAW, and MW is shown. CONCLUSIONS: Within this study's limitations, the ICW can determine the ideal dimension of the artificial teeth in the anterior maxillary arch. While the other facial parameters, including BZW, IAW, and MW, cannot be used for artificial teeth selection in Yemeni populations. CLINICAL SIGNIFICANCE: The findings of this study established a reference database of facial measurements and their correlation to dental arch and teeth width in Yemeni populations. So, it can be implemented in artificial teeth and dental prostheses design and construction.

Carbon Nanoparticles Extracted from Date Palm Fronds for Fluorescence Bioimaging: In Vitro Study.

Numerous studies have been reported on single- and multicolored highly fluorescent carbon nanoparticles (FCNPs) originating from various sources and their potential applications in bioimaging. Herein, multicolored biocompatible carbon nanoparticles (CNPs) unsheathed from date palm fronds were studied. The extracted CNPs were characterized via several microscopic and spectroscopic techniques. The results revealed that the CNPs were crystalline graphitic and hydrophilic in nature with sizes ranging from 4 to 20 nm. The unsheathed CNPs showed exemplary photoluminescent (PL) properties. They also emitted bright blue colors when exposed to ultraviolet (UV) light. Furthermore, in vitro cellular uptake and cell viability in the presence of CNPs were also investigated. The cell viability of human colon cancer (HCT-116) and breast adenocarcinoma (MCF-7) cell lines with aqueous CNPs at different concentrations was assessed by a cell metabolic activity assay (MTT) for 24 and 48 h incubations. The results were combined to generate dose-response curves for the CNPs and evaluate the severity of their toxicity. The CNPs showed adequate fluorescence with high cell viability for in vitro cell imaging. Under the laser-scanning confocal microscope, the CNPs with HCT-116 and MCF-7 cell lines showed multicolor fluorescence emissions, including blue, green, and red colors when excited at 405, 458, and 561 nm, respectively. These results prove that unsheathed CNPs from date palm fronds can be used in diverse biomedical applications because of their low cytotoxicity, adequate fluorescence, eco-friendly nature, and cheap production.

Antibacterial activity of the micro and nanostructures of the optical material tris(8-hydroxyquinoline)aluminum and its application as an antimicrobial coating.

Although tris(8-hydroxyquinoline)aluminum (Alq3), a fluorescent optical organometallic material, is known for its applications in optoelectronics, it has only few and limited applications in the biological field. In this study, the antibacterial activity of Alq3 micro and nanostructures was investigated. We prepared Alq3 nanostructures. We prepared nanosized Alq3 as rice-like structures that assembled into flower shapes with an α-crystal phase. Then, Alq3 micro and nanostructure antibacterial activities were estimated against seven human pathogenic bacterial strains. Besides, we compared their antibacterial activities with those of standard antibiotics. The minimal inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and IC50 were evaluated. Alq3 micro and nanostructure antibacterial activity showed considerable values compared to standard antibiotics. Besides, the obtained data revealed that the antibacterial activity of Alq3 in nanostructures with a new morphology is more than that in microstructures. The antibacterial activity of Alq3 nanostructures was attributed to their more surface interactions with the bacterial cell wall. The molecules of 8-hydroxyquinoline in the Alq3 structure could play crucial roles in its antibacterial activity. To apply the achieved results, Alq3 was incorporated with polystyrene (PS) in a ratio of 2% to fabricate a PS/Alq3 composite and used to coat glass beakers, which showed inhibition in the bacterial growth reduced to 65% compared with non-coated beakers. The finding of this study showed that Alq3 could be used as a promising antimicrobial coating.

Structural, morphological, and optical properties of carbon nanoparticles unsheathed from date palm fronds.

Several studies have reported the synthesis of carbon nanoparticles (CNPs) by various methods. In this study, an easy one-step process to unsheathe CNPs from date palm fronds through a top-down ball milling method has been reported. The CNPs were characterized using various spectroscopic and microscopic methods to determine their structural and morphological features, optical properties, crystallinity, physicochemical properties, and particle stability. Transmission electron microscopy (TEM) revealed that the obtained CNPs' size ranged from 4 to 22 nm in a crystalline form. Scanning electron microscopy (SEM) confirmed their spherical shape, while the maximum photoluminescence (PL) intensity was recorded at 464 nm when excited at 375 nm. The unsheathed CNPs produced a good quantum yield (QY) of 3.24%. Furthermore, the CNPs exhibited high Raman ratios of I D/I G and I 2D/I G with values of 0.59 and 0.04, respectively, verifying their multilayer crystalline graphitic nature. These Raman ratios also agree with the X-ray diffractometry (XRD) results. The CNPs' sp2 and sp3 carbon bonds were confirmed by X-ray photoelectron spectroscopy (XPS), with oxygen on the surface forming carboxyl and carbonyl groups with no other observable impurities. Furthermore, the extracted CNPs showed excellent PL properties for up- and down-conversion. These properties are exemplary for low-cost biomass with potential applications in biomedicine. Therefore, the extracted CNPs reported in this study have potential applications in optical imaging.

High Thermoelectric Power Generation by SWCNT/PPy Core Shell Nanocomposites.

Polypyrrole (PPy) is a conducting polymer with attractive thermoelectric (TE) properties. It is simple to fabricate and modify its morphology for enhanced electrical conductivity. However, such improvement is still limited to considerably enhancing TE performance. In this case, a single-wall carbon nanotube (SWCNT), which has ultrathin diameters and exhibits semi-metallic electrical conductivity, might be a proper candidate to be combined with PPy as a core shell one-dimensional (1D) nanocomposite for higher TE power generation. In this work, core shell nanocomposites based on SWCNT/PPy were fabricated. Various amounts of pyrrole (Py), which are monomer sources for PPy, were coated on SWCNT, along with methyl orange (MO) as a surfactant and ferric chloride as an initiator. The optimum value of Py for maximum TE performance was determined. The results showed that the SWCNT acted as a core template to direct the self-assembly of PPy and also to further enhance TE performance. The TE power factor, PF, and figure of merit, zT, values of the pure PPy were initially recorded as ~1 µW/mK2 and 0.0011, respectively. These values were greatly increased to 360 µW/mK2 and 0.09 for the optimized core shell nanocomposite sample. The TE power generation characteristics of the fabricated single-leg module of the optimized sample were also investigated and confirmed these findings. This enhancement was attributed to the uniform coating and good interaction between PPy polymer chains and walls of the SWCNT through π-π stacking. The significant enhancement in the TE performance of SWCNT/PPy nanocomposite is found to be superior compared to those reported in similar composites, which indicates that this nanocomposite is a suitable and scalable TE material for TE power generation.

Structural and Magnetoelectrical Properties of MFe2O4 (M = Co, Ni, Cu, Mg, and Zn) Ferrospinels Synthesized via an Egg-White Biotemplate.

Nanocrystalline metal ferrites (MFe2O4, M = Co, Ni, Cu, Mg, and Zn) were successfully synthesized via autocombustion synthesis using egg white. X-ray diffraction (XRD) measurements revealed the crystallization of the entire ferrites either in the tetragonal structure, such as in the case of CuFe2O4, or cubic spinels such as in other studied ferrites. The Fourier transform infrared spectral study revealed the characteristic vibration bands of ferrites. Compared to other synthesis methods, the observed variation in the obtained structural parameters could be due to the different cation distribution of the prepared ferrites. In agreement with XRD measurements, the transmission electron microscopy images showed agglomerated particles with cubic morphology for all ferrites. On the other hand, CuFe2O4 showed tetragonal morphology. The magnetization values were found to vary with the type of the metal ion, and CoFe2O4 showed the highest one (42.8 emu/g). Generally, the lower magnetization values obtained than those reported in the literature for all studied ferrites could be attributed to the smaller particle sizes or the cation redistribution. The obtained coercivity values are observed to be higher than their related values in the literature, exhibiting the impact of the present synthesis route. Ac-conductivity as a function of temperature and frequency indicated semiconducting properties with the observed change in the conduction mechanism by increasing the temperature. The obtained low dielectric constant values could suggest using the entire ferrites in high-frequency applications such as microwave devices.

Spectroscopic study of the effect of low dose fast neutrons on the hemoglobin structure.

Cosmic rays, nuclear accidents, and neutron therapy could be sources for exposure to low-dose fast neutrons. However, the study of low dose effects needs sentient techniques to detect slight alteration happen by this low dose. Herein, the effects of low-dose fast neutrons on the structure of hemoglobin (Hb) using spectroscopic techniques, namely, Fourier transform infrared (FTIR), Raman, and ultraviolet-visible (UV-Vis) spectroscopic. Forty (20 control/20 irradiated) female Wistar rats were used in this work. The irradiated rats were irradiated to low-dose at a total dose of 10 mGy from a fast neutron source (241Am-Be, 0.2 mGy/h). Multivariate analyses were applied to differentiate between the control and irradiated rats' Raman spectra. The erythrocytes samples were isolated from whole blood to explore the Hb structure. FTIR results revealed changes in the ν(S-H) bond of α-104 and ß-93 cysteines by low-dose fast neutrons. Raman spectra showed changes in the spin state and oxidation state of the iron atom of the Hb. Besides, deformation in methine C-H was recorded. UV-Vis spectroscopy disclosed that the irradiated rats might be more susceptive to oxidation than control rats. The study deduced that the low dose fast neutron could cause tiny Hb structure changes by indirect effects. Besides, the spectroscopic techniques showed a potent ability to reveal tiny changes in the Hb structure that happened by a low dose of fast neutrons.

Multivalency in CXCR4 chemokine receptor targeted iron oxide nanoparticles.

The CXCR4 chemokine receptor is an important biomolecular target in cancer diagnostics and therapeutics. In a new multivalent approach, iron oxide nanoparticles were conjugated with multiple binding units of a low affinity azamacrocylic CXCR4 antagonist. The silica coated nanostructure has good suspension stability, a mode size of 72 nm and high affinity for CXCR4, showing >98% inhibition of anti-CXCR4 mAb binding in a receptor binding competition assay on Jurkat cells.

Effects of aluminum chloride and coenzyme Q10 on the molecular structure of lipids and the morphology of the brain hippocampus cells.

Aluminum chloride (AlCl3) is a neurotoxic substance, while coenzyme Q10 (CoQ10) is considered a lipid antioxidant. Herein, their effects on the molecular structure of lipids and the morphology of the hippocampus brain tissue were investigated. Three groups of Wistar albino male rats were used in this study. For four weeks, one group was kept as a control group; the second group was given AlCl3; the third group was given AlCl3/CoQ10. Fourier transform infrared (FTIR) and histopathological examinations were utilized to estimate alterations in the molecular structure of the lipids and the cell morphology, respectively. The FTIR spectra revealed considerable decreases in the CH contents and alterations in the molecular ratios of olefinic[double bond, length as m-dash]CH/νas(CH3), νas(CH2)/νas(CH3), and νas(CH2)/[νas(CH2) + νs(CH2)] in the group given AlCl3. However, no significant changes were detected in those rats given AlCl3/CoQ10. Histopathology images uncovered shrinking and dark centers in the pyramidal cells of brain tissue hippocampal cells. The diameters of the pyramidal cells were estimated to be 4.81 ± 0.55 µm, 4.04 ± 0.71 µm, and 4.63 ± 0.71 µm for the control, AlCl3, and AlCl3/CoQ10 groups, respectively. The study showed that the AlCl3 could cause a shrinking of around 16% in the hippocampus pyramidal cells; besides, CoQ10 is a powerful therapeutic antioxidant to help restore the hippocampal neurons to a regular state.

Correction: Effects of aluminum chloride and coenzyme Q10 on the molecular structure of lipids and the morphology of the brain hippocampus cells.

[This corrects the article DOI: 10.1039/D1RA03786B.].

Risk estimation of the low-dose fast neutrons on the molecular structure of the lipids of peripheral blood mononuclear cells.

Our immune system can be exposed to neutral ionizing radiation. This work proposed to investigate the impacts of low-dose fast neutrons on the molecular structure of the lipids of peripheral blood mononuclear cells (PBMCs) as the primary immune cells. The effects have been followed at the time of 0, 2, 4, and 8 days after neutron exposure. Sixty-four female Wistar rats were used in this work. Thirty-two of them were irradiated using a low-dose fast neutron (241Am-Be, 0.2 mGy/h). The other thirty-two were utilized as a control group. The changes in their lipids molecular structure were investigated using Fourier transform infrared (FTIR) spectroscopy. Besides, lipids were extracted, and the total phospholipids contents were estimated. At the time of 2 and 4 days after irradiation, the results showed significant changes in the molecular structure of lipids in those irradiated samples compare with their control samples, and multivariate analysis succeeded in differentiating between control and irradiated rats. In contrast, no alterations between control and irradiated were detected at the time of 0 and 8 days after. The low-dose fast neutron could induce free radicals, which indirectly affect the molecular structure of the lipids and could damage the phospholipids molecules, and the damage could be repaired.

Effect of low-dose fast neutrons on the protein components of peripheral blood mononuclear cells of whole-body irradiated Wistar rats.

The immune system is exposed to extremely low doses of neutrons under different circumstances, such as through exposure to cosmic rays, nuclear accidents, and neutron therapy. Peripheral blood mononuclear cells (PBMCs) are the primary immune cells that exhibit selective immune responses. Changes in the functions of the protein components of PBMC can be induced by structural modifications of these proteins themselves. Herein, we have investigated the effect of low-dose fast neutrons on PBMC proteins at 0, 2, 4, and 8 days post-whole body irradiation. 64 Wistar rats were used in this study of which, 32 were exposed to fast neutrons at a total dose of 10 mGy (241Am-Be, 0.2 mGy/h), and the other 32 were used as controls. Blood samples were drawn, and PBMCs were isolated from whole blood. Fourier transform infrared (FTIR) spectroscopy and fluorescence spectroscopy were used to estimate the changes in the proteins of PBMCs. An alkaline comet assay was performed to assess DNA damage. Hierarchical cluster analysis (HCA) and principal components analysis (PCA) were utilized to discriminate between irradiated and non-irradiated samples. FTIR and fluorescence spectra of the tested samples revealed alterations in the amides and tryptophan, and therefore protein structure at time intervals of 2 and 4 days post-irradiation. No changes were recorded in samples tested at time intervals of 0 and 8 days post-irradiation. The FTIR band intensities of the PBMC proteins of the irradiated samples decreased slightly and were statistically significant. Curve fitting of the amide I band in the FTIR spectra showed changes in the secondary structure of the proteins. At 2 days post-irradiation, fluorescence spectra of the tested samples revealed decreases in the band tryptophan. The comet assay revealed low levels of DNA damage. In conclusion, low-dose fast neutrons can affect the proteins of PBMC.

Effective reinforcements for thermoplastics based on carbon nanotubes of oil fly ash.

Carbon nanotubes (CNTs) are widely investigated for preparing polymer nanocomposites, owing to their unique mechanical properties. However, dispersing CNTs uniformly in a polymer matrix and controlling their entanglement/agglomeration are still big technical challenges to be overcome. The costs of their raw materials and production are also still high. In this work, we propose the use of CNTs grown on oil fly ash to solve these issues. The CNTs of oil fly ash were evaluated as reinforcing materials for some common thermoplastics. High-density polyethylene (HDPE) was mainly reinforced with various weight fractions of CNTs. Xylene was used as a solvent to dissolve HDPE and to uniformly disperse the CNTs. Significantly enhanced mechanical properties of HDPE reinforced at a low weight fraction of these CNTs (1-2 wt.%), mainly the tensile strength, Young's modulus, stiffness, and hardness, were observed. The tensile strength and Young's modulus were enhanced by ~20 and 38%, respectively. Moreover, the nanoindentation results were found to be in support to these findings. Polycarbonate, polypropylene, and polystyrene were also preliminarily evaluated after reinforcement with 1 wt.% CNTs. The tensile strength and Young's Modulus were increased after reinforcement with CNTs. These results demonstrate that the CNTs of the solid waste, oil fly ash, might serve as an appropriate reinforcing material for different thermoplastics polymers.