Experimental, analytical, and simulation studies of modified concrete mix for radiation shielding in a mixed radiation field.

The current study assessed two concrete mixes prepared using dolomite and barite/limonite aggregates to shield against both energetic photons and neutrons. After that, a designed mix which comprised barite/goethite aggregates plus fine-powdered boron carbide additive, was proposed to improve the overall radiation shielding properties and in the same time, doesn't compromise or even improve the physic-mechanical properties of the mature concrete. The assessment started first with intensive experimental investigations to investigate the prepared mixes' shielding capabilities against both γ-rays and fast neutrons. Then, analytical computations were performed via number of reliable software programs such as; Phy-X, NXCom, MRCsC, JANIS-4, and MCNP5, in order to confirm the experimental results and to validate the created Monte-Carlo models. Finally, an intensive radiation shielding assessment for all concrete mixes understudy using, mainly, the validated MCNP models, was performed. The obtained results have revealed the superiority of barite mixes over the dolomite mix concerning attenuating photons moreover, the proposed designed mix has shown superiority over the other two prepared mixes considering shielding against; energetic photons, fast/thermal neutrons, and secondary emitted γ-rays, which nominates this mix to be a suitable universal shield that can be used even in mixed radiation fields.

A semi-empirical method for efficiency calibration of an HPGe detector against different sample densities.

In this work, a semi-empirical equation in terms of γ-energy, and sample density is derived, proposed, benchmarked, and applied for the peak efficiency calibration of an HPGe detector with respect to an axial source-to-detector configuration. The samples are in the form of cone-shaped Marinelli beakers of different densities in the range 0.7-1.6 g/cm3. The method employs the experimental measurements with the ANGLE-3 software calculations using the efficiency transfer method. The peak efficiency curve of an HPGe detector is calculated using the experimental measurements of point-like sources (133Ba, 137Cs, and 60Co). The ANGLE-3 software is then used to calculate the peak efficiency curves for samples with different densities in the γ-energy range 81-1332 keV. The peak efficiency curves are then fitted to get the energy coefficient; in addition, a linear relationship is then constructed between the energy coefficients and sample densities to get the density coefficients, and the derived equation as well. The derived equations are benchmarked using the peak efficiency curves by ANGLE-3 software in comparison with that the equation results. The results are found to be in agreement with an average relative error of about 1.5%. In addition, the derived equations are applied to estimate the activity concentration of radionuclides present in 5 cone-shaped samples with different densities using experimental measurements. The activity results are found to be in agreement with the certified values with an average relative error of about 2%. The limitation of the proposed equations is also discussed with respect to different material densities and different chemical compositions and correction factors for material composition self-attenuation for various materials are also presented.

Impact of core stability exercises vs. interferential therapy on pelvic floor muscle strength in women with pelvic organ prolapse.

OBJECTIVE: Pelvic organ prolapse (POP) is the descent of the pelvic organs into or through the vaginal walls. Females who have prolapse have symptoms that interfere with their daily lives, sexual function, and exercise. POP can have a negative effect on one's sexuality and body image. This study attempted to assess the significance of core stability exercises vs. interferential therapy on the power of the pelvic floor muscles in females with prolapsed pelvic organs. PATIENTS AND METHODS: A randomized control trial was conducted on forty participants (aged between 40-60 years, diagnosed with mild degree pelvic organ prolapse participated in the research. Participants were randomly divided into two groups: (group A; n = 20) and (group B; n = 20). The participants were tested twice, before and after 12 weeks, during which group (A) performed core stability exercises while group (B) received interferential therapy. A modified Oxford grading scale and the perineometer were used to assess how the vaginal squeeze pressure changed. RESULTS: The study's findings demonstrated that the modified Oxford grading scale values and vaginal squeeze pressure had a non-statistically significant difference (p-value ≥ 0.05) between both groups pre-treatment while had a statistically significant difference (p-value ≤ 0.05) between both groups post-treatment in favor of group A. CONCLUSIONS: It was concluded that both training programs are efficient at strengthening the pelvic floor muscles, but the core stability exercises were more effective.

µEvaluation of microcystin-LR absorption using an in vivo intestine model and its effect on zebrafish intestine.

Microcystin-LR (MC-LR) is regarded as one of the most toxic microcystins (MCs) isoforms. Microcystins could cause multiple organs dysfunction, and more attention has been drawn to the toxic effects on the gastrointestinal disorder. By using ex vivo everted gut sac model in 6 fish (Carassius auratus, Megalobrama amblycephala, Hypophthalmichthys molitrix, Aristichthys nobilis, Ctenopharyngodon idellus and Cyprinus carpio) and determining the accumulation of MC-LR in zebrafish intestine, we found a dose-dependent manner in the absorption and accumulation of MC-LR. Until now, little studies have been reported concerning the gut microbiota composition caused by different MC-LR exposure. The present study is the first time characterized the phylogenetic composition and taxonomic of the bacterial communities growth in the intestines of zebrafish treated with MC-LR using 16S rRNA pyrosequencing. After 30 days of treatment with 0, 1, 5 or 20 µg/L MC-LR, the alpha and beta diversity did not generate significant differences, indicating the existence of a core microbiota. However, db-RDA analysis showed that treatment with 20 µg/L MC-LR changed the characteristics of high abundances microbiota. The expression of Oatp2b1, stress related enzyme activities in gut and their associations with gut microbiota were also determined. The identified phylotypes including Actinobacteria, Lactobacillus and some opportunistic pathogens highlight the increasing risks of pathogen invasion and recovery tendency via potential probiotics resistance in zebrafish exposed to MC-LR.

Effects of a novel marine probiotic, Lactobacillus plantarum AH 78, on growth performance and immune response of Nile tilapia (Oreochromis niloticus).

AIMS: Evaluation of the efficacy of marine lactic acid bacteria, Lactobacillus plantarum AH 78, on growth performance and immune response of Nile tilapia (Oreochromis niloticus) challenged with Aeromonas hydrophila. METHODS AND RESULTS: Marine probiotic, Lact. plantarum AH 78, was incorporated in Nile tilapia diets at 0·0, 0·5, 1·0 or 2·0% (w/w). The diets were fed to juvenile Nile tilapia for 40 days, after which they were challenged with pathogenic bacterium, Aer. hydrophila. The best growth rates and feed efficiency were obtained at 0·5% probiotic, while fish survival was not affected by dietary probiotic. After challenge with Aer. hydrophila immunological responses and survival were recorded at 1·0% probiont. Likewise, significant up-regulation of the expression of cytokine genes, IL-4, IL-12 and IFN-γ, in fish livers was found at 1·0% probiont, compared to the control diet. Concomitantly, AH 78 colonized the intestinal mucosa of treated fish, even after reverting to the control diet, and remained viable in the feed stored at 4°C up to 12 months. CONCLUSIONS: Marine Lact. plantarum AH 78 at 0·5-1·0% inclusion level conferred the best performance and immune response of Nile tilapia challenged with Aer. hydrophila. SIGNIFICANCE AND IMPACT OF THE STUDY: Marine Lact. plantarum AH 78 could be considered as a potential probiotic to control disease outbreaks in farmed Nile tilapia.

Structural and functional effects of early exposure to 4-nonylphenol on gonadal development of Nile tilapia (Oreochromis niloticus): a-histological alterations in ovaries.

The present study investigated the gonads alterations of mature female Oreochromis niloticus caused by different concentrations (0, 40, 60, 100 µg/L) of 4-nonylphenol (NP) and also its effect on steroidogenesis. A tendency for a dose-dependent reduction in the gonadosomatic index, fecundity and oocytes diameter in the NP-exposed groups was observed. Histological examination revealed that NP impairs gonadal growth clearly shown in the oocyte development and differentiation. Also, the estrogenic activity of such NP was identified through 11-ketotestosterone, 17b-estradiol and vitellogenin which were affected significantly by the applied concentrations. The study indicates that NP has estrogenic potency-induced marked alteration in the sexual development including gonadal maturation, spawning time and egg production.

Structural and functional effects of early exposure to 4-nonylphenol on gonadal development of Nile tilapia (Oreochromis niloticus): b-histological alterations in testes.

The present study investigates the effects of different doses (0, 40, 60, 100 µg/L) of 4-nonylphenol (NP) on testis histology and sperms motility of mature Oreochromis niloticus. A tendency for a dose-dependent reduction in the gonado-somatic index (GSI) in the NP-exposed groups was observed. Histological examination revealed that high doses of NP (60 and 100 µg/L) cause hyperplasia of interlobular connective tissue components coincide with decrease in the size of seminiferous lobules and amount of lumen spermatozoa in comparison with the control and low-dose (40 µg/L)-exposed groups. In addition, within the seminiferous lobules, rupture of spermatogenic cysts, vacuolation and necrosis of primary spermatocytes due to damage of sertoli cells were clearly observed and lead to decrease in advanced spermatogenic cells. The highest dose caused significant decrease in the GSI associated with appearance of testis-ova (intersex) state. The percentage of abnormal sperms increased with increasing the dose of NP reaching to 96 % for those subjected to 100 µg NP/L, while it was only 11 % for the control group specimens. The study indicates that NP has estrogenic potency induced marked alteration in the sexual development including inhibition in testicular growth and deformation in the sperms.