Skip to main content

Optimizing gamma-ray shielding for boron neutron capture therapy by using unglazed ceramic composites

Research Abstract

In this study, the researchers investigated the effectiveness of different ceramic samples in filtering gamma rays emitted by various sources. The samples, which contained varying concentrations of lead and barium, were evaluated for their potential use in beam-shaping assembly systems for Boron Neutron Capture Therapy techniques, specifically those using the 252Cf neutron source for cancer treatment. Stilbene and NaI (Tl) were used to measure the total and pure gamma rays in this study. In addition, theoretical calculations using the Phy-X/PSD software have been conducted across a broad energy range, spanning from 0.001 to 18 MeV. These calculations aim to determine the attenuation of gamma rays and the relative deviations compared to the corresponding measured gamma-ray energies. Various composites with different percentages of additives and thicknesses, ranging from 0.8 cm to 4 cm, have shown satisfactory attenuation properties for gamma-ray shielding applications. However, the samples containing lead, especially the unglazed ceramic composites with 15 % lead and 4 cm thickness, were found to have the most preferred attenuation properties. The results obtained indicate that samples with a higher lead content are more effective attenuators compared to those with additional barium. In addition, the relationship between the transmission gamma ray factor and the percentage of additives and energies of gamma rays can be determined from the experimental linear attenuation coefficient coefficients. In addition, various coefficients such as the mass attenuation coefficient, half-value layer, effective atomic numbers, and effective electron densities are studied theoretically for the unglazed ceramic samples. The dose rate is also taken into consideration.

Research Authors
M.S. Ali, G.S. Hassan , G.M. Shoraiet , A.M. Abdelmonem
Research Date
Research Department
Research Journal
Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms
Research Member
Research Pages
165450
Research Vol
554
Research Year
2024

Quantitive variation of male and female-specific compounds in 99 drosophilid flies

Research Abstract

Variation in sex pheromones is regarded as one of the causes of reproductive isolation and speciation. We recently identified 51 male- and female-specific compounds – many of which function as sex pheromones – in 99 drosophilid species[1]. Here, we report that despite many of these compounds being shared between species, their quantities differ significantly. For example, although 34 drosophilid species share the male-specific compound cis-vaccenyl acetate (cVA), which plays a critical role in regulating various social and sexual behaviors, the amount of cVA can differ by up to 600-fold between different species. Additionally, we found 7-tricosene, the cuticular hydrocarbon pheromone, present in 35 Drosophila species. Our findings indicate that 7-tricosene is equally present in both sexes of 14 species, more abundant in males of 14 species, and more abundant in females of 7 species. We provide raw data on the concentration of potential pheromone components in the 99 drosophilids, which can provide important insights for further research on the behavior and evolution of these species. Quantitative variations highlight species-specific patterns, suggesting an additional mechanism for reproductive isolation built on specific combinations of compounds at set concentrations.

Research Authors
Mohammed A. Khallaf , Melissa Diaz-Morales, Bill S. Hansson, Markus Knaden
Research Date
Research Department
Research File
Research Journal
Data in Brief
Research Member
Research Publisher
Elsevier
Research Website
https://www.sciencedirect.com/science/article/pii/S2352340924008357
Research Year
2024

How conspecific and allospecific eggs and larvae drive oviposition preference in Drosophila

Research Abstract

Where to lay the eggs is a crucial decision for females as it influences the success of their offspring. Female flies prefer to lay eggs on food already occupied and consumed by larvae, which facilitates social feeding, but potentially could also lead to detrimental interactions between species. Whether females can modulate their attraction to cues associated with different species is unknown. Here, we analyzed the chemical profiles of eggs and larvae of 16 Drosophila species, and tested whether Drosophila flies would be attracted to larvae-treated food or food with eggs from 6 different Drosophila species. The chemical analyses revealed that larval profiles from different species are strongly overlapping, while egg profiles exhibit significant species specificity. Correspondingly, female flies preferred to lay eggs where they detected whatever species’ larval cues, while we found a significant oviposition preference only for eggs of some species but not others. Our findings suggest that both larval and egg cues present at a given substrate can drive oviposition preference in female flies.

Research Authors
Rolando D Moreira-Soto, Mohammed A Khallaf, Bill S Hansson, Markus Knaden
Research Date
Research Department
Research File
bjae0121.pdf (1.63 MB)
Research Journal
Chemical Senses
Research Member
Research Pages
bjae012
Research Publisher
Advance access publication
Research Rank
Q1
Research Vol
Chemical Senses, 2024, 49
Research Website
https://academic.oup.com/chemse/article/doi/10.1093/chemse/bjae012/7644546
Research Year
2024

Endophtic fungus Neopestalotiopsis clavispora AUMC15969: Biosynthesis and characterization of exopolysaccharides and biodiesel production

Research Abstract

Exopolysaccharides (EPS) are bioactive metabolites with high molecular weight and are produced by several microorganisms such as endophytic fungi. Thus, the aim of the present study was designed to explore the biosynthesis and characteristics of EPS by the endophytic fungus Neopestalotiopsis clavispora AUMC15969 and then investigate some environmental and nutritional factors that affect their production. Moreover, we estimated an additional value, namely the production of bio diesel. Maximum production of EPS was 7.86 g/L when N. clavispora was grown on lactose as the sole carbon source and peptone as the nitrogen source, respectively, and pH 7 at 35 °Cfor 10 days. The produced EPS had a total sugar content of 0.93 g/g where protein content was 0.076 g/g. It revealed a strong antioxidant activity that improved with increasing sample concentration, with the optimum concentration of 10 mg/mL producing 83.1% DPPH radical scavenging activity with an IC50 equal to 3.89 mg/mL. The extracted lipid from the fungal mycelia at the end of the fermentation process was 31.76% w/w. The biodiesel produced from the transesterification of lipids was 87.4% total fatty acid methyl esters. The present study demonstrated the potential production of EPS and lipid biopolymers in one-pot fermentation which could use as a resource for industrial technologies

Research Authors
Mostafa M. Koutb1,2 · Elhagag A. Hassan1 · Nemmat A. Hussein1 · Fahd M. Abdelkarem3 · Hussein H. Abulreesh2 · Khaled Elbanna2,4 · Yulu Yang5 · El‑Sayed Salama5 · Maysa M. Ali
Research Date
Research Journal
Biomass Conversion and Biorefinery
Research Member

Friedel–Crafts Chemistry. Part 63. Syntheses of some condensed N-heterocyclic systems via combined Darzens and Friedel-Crafts approaches

Research Abstract
Research Authors
Hassan AK Abd El-Aal, Ali A Khalaf
Research Date
Research Department
Research Journal
Arkivoc
Research Year
2024

Synergistic effect of Bacillus subtilis and Benzothiadiazole (Bion®) on the suppression of Fusarium oxysporum and the enhancement of disease resistance in Capsicum annuum.

Research Authors
Abo-Elyousr KAM, Nashwa M.A. Sallam , Magdy A. A. Mousa, Muhammad Imran and Ismail R. Abdel-Rahim
Research Date
Research Journal
Journal of Plant Pathology
Research Member
Research Pages
1-12
Research Publisher
Springer International Publishing
Research Year
2023

Experimental and computational explorations for the inhibitive performances of synthesized green surfactants against the corrosion of copper in nitric acid

Research Abstract

The inhibitory characteristics of two recently synthesized biosurfactants based on amino acids, namely sodium Nhexadecyl glycine (I) and sodium N-hexadecyl valine (II), concerning copper corrosion in 1.0 M HNO3 were studied at variance of temperatures. FTIR analysis was utilized to identify the chemical structures of both synthesized biosurfactants. Various techniques were employed in this study. According to the results, the synthesized biosurfactants were played as proficient inhibitors for copper corrosion and their inhibition efficiencies (% IEs) were concentration- and structure-dependent with respect to them. At a concentration of 400 mg/L of the synthesized biosurfactants and at 298 K, the average% IE was found to be 90% for biosurfactant I and 85% for biosurfactant II. The gained higher% IEs were suggested to as a result of the potent adsorption of these biosurfactants on the surface of copper and the type of adsorption was discovered to be physical and followed Langmuir adsorption isotherm. The obtained findings signified that the synthesized biosurfactants exhibited mixed-type and interface-type inhibitors. The thermodynamic and kinetic parameters were assessed and discussed. Furthermore, the kinetics of corrosion of copper as well as its inhibition were also investigated. The density functional theory (DFT) and molecular dynamics (MD) simulations emphasized the inhibitory mechanism of the examined biosurfactants and proved the adsorption of the biosurfactants’ molecules on the copper surface. Theoretical modeling also demonstrated that the biosurfactant I exhibited a greater% IE compared to biosurfactant II. The experimental results gained from all employed measurements are largely reliable with each others and are in a good consistent with the theoretical studies signifying the validity of these results.

Research Authors
Nada Alqarni, Belal El-Gammal, Thoraya A. Fargaly, Ahmed A.K. Mohammed, Ahmed Fawzy
Research Date
Research Journal
Journal of Molecular Structure
Research Pages
1-18
Research Publisher
Elsevier
Research Rank
Q2
Research Vol
1319
Research Website
https://doi.org/10.1016/j.molstruc.2024.139439
Research Year
2025

One-pot synthesis of N’-(thiophen-2-ylmethylene)isonicotinohydrazide Schiff-base as a corrosion inhibitor for C-steel in 1 M HCl: Theoretical, electrochemical, adsorption and spectroscopic inspections

Research Abstract

Although carbon steel (CS) is an essential component utilized in many industries, it regrettably corrodes when exposed to acidic conditions. Schiff bases have recently become more concerned with the corrosion prevention of CS. Hydrazides and the related compounds shown to be effective inhibitors of CS corrosion in acids. These compounds are commonly employed as origins or intermediates to several key molecules in the synthesis of organic compounds, and they are highly sought after due to their wide range of biological and therapeutic applications. They have anti-bacterial, anti-malarial, anti-fungal, and anticancer properties, as well as corrosion protection. Hence, the inhibitory effectiveness of a new synthesized (E)-N’-(thiophen-2-ylmethylene) isonicotinohydrazide (TMNH) Schiff-base for the corrosion of CS in 1 M HCl was explored. The structure of TMNH was validated by FT-IR and 1 H NMR spectroscopy. A number of chemical, spectral, and electrochemical techniques such as potentiodynamic polarization (PDP), electrochemical impedance spectroscopy (EIS), and mass loss (ML) have been used to evaluate its anticorrosion power. PDP measurements showed that it is a mixed-type inhibitor. In addition, EIS measurements showed that Rct increased sharply from 37 without the corrosion inhibitor to 589 Ω cm-2 in the presence of 1 mM TMNH and from PDP scans, the corresponding icorr decreased dramatically from 0.6158 to 0.0314 μA cm-2. ML tests have proven their effectiveness, achieving an inhibitory efficiency of 95.3 %. Adsorption studies were also conducted to determine the nature of the corrosion retardation mechanism. The TMNH inhibitor was spontaneously chemically/physically adsorbed onto the CS surface following the Langmuir isotherm. Statistical calculations were also applied to verify the accuracy of the experimental results. The Monte Carlo model showed that the inhibitory molecules adsorbed flat on only one side, increasing the chances of adsorption

Research Authors
Arafat Toghan, Hanan Alhussain, Ahmed Fawzy, Moustafa M.S. Sanad, Sami A. AlHussain, Emad M. Masoud, Heqing Jiang, Ahmed A. Farag
Research Date
Research Journal
Journal of Molecular Structure
Research Member
Research Pages
1-12
Research Publisher
Elsevier
Research Rank
Q2
Research Vol
1318
Research Website
https://doi.org/10.1016/j.molstruc.2024.139315
Research Year
2024

Antimicrobial and cytotoxic activities of flavonoid and phenolics extracted from Sepia pharaonis ink (Mollusca: Cephalopoda)

Research Abstract

Background

Several studies have been reported previously on the bioactivities of different extracts of marine molluscs. Therefore, we decided to evaluate the cytotoxic and antimicrobial activities of S. pharaonis ink as a highly populated species in the Red Sea. We extracted the flavonoids from the ink and analyzed their composition. Then we evaluated systematically the cytotoxic and antimicrobial properties of this extract. A pharmacokinetic study was also conducted using SwissADME to assess the potential of the identified flavonoids and phenolic compounds from the ink extract to be orally active drug candidates.

Results

Cytotoxic activity was evaluated against 5 cell lines (MCF7, Hep G2, A549, and Caco2) at different concentrations (0.4 µg/mL, 1.6 µg/mL, 6.3 µg/mL, 25 µg/mL, 100 µg/mL). The viability of examined cells was reduced by the extract in a concentration-dependent manner. The highest cytotoxic effect of the extract was recorded against A549 and Hep G2 cancer cell lines cells with IC50 = 2.873 and 7.1 µg/mL respectively. The mechanistic analysis by flow cytometry of this extract on cell cycle progression and apoptosis induction indicated that the extract arrests the cell cycle at the S phase in Hep G2 and MCF7, while in A549 cell arrest was recorded at G1 phase. However, it causes G1 and S phase arrest in Caco2 cancer cell line. Our data showed that the extract has significant antimicrobial activity against all tested human microbial pathogens. However, the best inhibitory effect was observed against Candida albicans ATCC 10,221 with a minimum inhibitory concentration (MIC) of 1.95 µg/mL. Pharmacokinetic analysis using SwissADME showed that most flavonoids and phenolics compounds have high drug similarity as they satisfy Lipinski’s criteria and have WLOGP values below 5.88 and TPSA below 131.6 Å2.

Conclusion

S. pharaonis ink ethanolic extract showed a promising cytotoxic potency against various cell lines and a remarkable antimicrobial action against different pathogenic microbial strains. S. pharaonis ink is a novel source of important flavonoids that could be used in the future in different applications as a naturally safe and feasible alternative of synthetic drugs.

Research Authors
Asmaa R. Abdel-Malek, Alaa Y. Moustafa & Shimaa H. Salem
Research Date
Research Journal
BMC Biotechnology
Research Publisher
Springer Nature
Research Vol
24, Article number: 54
Research Website
https://doi.org/10.1186/s12896-024-00880-3
Research Year
2024

Sonochemical synthesis of Cu (II) coordination polymer: Structural characterization and antibacterial activities against human pathogenic bacteria

Research Abstract

Self-assembly of benzene-1,4-dicarboxylate with Cu (II) using ultrasonic assisted approaches with 2-aminothiazole as secondary ligand produce a coordination polymer of the formula {[Cu (BDC)(AZ) (H2O)]. H2O}n. The structure was investigated using elemental analysis, IR spectroscopy, X-ray diffraction (XRD) and Transmission electron microscopy (TEM). A crystalline coordination polymer was obtained via the ultrasonic irradiation. Copper compounds exhibited promising inhibitory action against six human pathogenic bacteria (Bacillus subtilis, Bacillus cereus, Escherichia coli, Klebsiella pneumoniae, Micrococcus luteus, and Serratia marcescens). The most effective antibacterial treatments were after sonication for 70 min especially at 100 µg/ml gives total counts 32.96 × 107 ± 0.56, 32.68 × 107 ± 0.84, 28.32 × 107 ± 1.2, 9.16 × 107 ± 0.52, 20.92 × 107 ± 0.2, and 30.36 × 107 ± 0.28, for B. subtilis, B. cereus, E. coli, K. pneumoniae, M. luteus, and S. marcescens comparing with control samples 82.84 × 107 ± 5.96, 94.04 × 107 ± 3, 65.24 × 107 ± 1.08, 32.92 × 107 ± 0.6, 36.92 × 107 ± 0.2, and 59.52 × 107 ± 0.4, respectively.

Research Authors
Mervat Ibrahim a b, Ghada Abd-Elmonsef Mahmoud c, Aref A. M. Ali d, Dina M. Fouad d
Research Date
Research Journal
Inorganic Chemistry Communications
Research Pages
112951
Research Publisher
َ@ ELSIEVER
Research Rank
International Q1
Research Website
https://www.sciencedirect.com/science/article/pii/S1387700324009353
Research Year
2024
Subscribe to