Coral recruitment and early benthic community development on several materials used in the construction of artificial reefs and breakwaters

Artificial reefs are increasingly being promoted as a means to mitigate impacts from human activities in coastal urban areas. Coastal defense structures such as breakwaters are becoming recognized as large-scale artificial reefs that support abundant and diverse marine communities and play important roles in coastal ecology and management. However, there is limited understanding of how substrate materials used to construct artificial reefs or breakwaters can influence the development of habitat-forming benthic organisms. To assess the influence of substrata on coral recruitment and overall benthic community development, we deployed standard-size tiles of materials used in the construction of breakwaters and artificial reefs (concrete, gabbro, granite, and sandstone), along with terra-cotta for comparative purposes, at two breakwaters (DDD, PRT) and two natural reef sites (NR1, NR2) in Dubai, United Arab Emirates, for one year. Kruskal-Wallis ANOVA with post-hoc Mann-Whitney U-tests were used to examine differences in coral recruitment among sites and materials. Coral recruitment was highest at the DDD (4.9 ± 0.5 recruits 100 cm^− 2), while recruitment was low and did not differ among other sites (PRT: 0.1 ± 0.04, NR1:0.3 ± 0.1, NR2: 0.1 ± 0.03 recruits 100 cm^− 2). There were significant differences in coral recruitment among materials at DDD, where gabbro had higher recruit densities than concrete and sandstone; sandstone also contained less coral recruits than terra-cotta. Variability associated with low coral recruit densities precluded significant differences among materials at other sites. Overall benthic community structure differed more as a result of differences among sites than among substrate materials. Higher community dissimilarity was observed among sites than among material in SIMPER analysis, and significant differences were only observed among sites in ANOSIM. Univariate comparison of the benthos correlated with community differences in NMS ordination also showed significant differences among sites but not material. Overall, these results indicate that site-specific differences in recruitment patterns are more important in determining early benthic community structure and coral recruitment than are differences among substrate material. However, where coral recruitment is high, these results suggest that gabbro should be used preferentially over concrete or sandstone where it is feasible, but that granite may be a suitable alternative where it is the dominant stone. Coral recruitment on terra-cotta was comparable to all materials but sandstone, supporting its continued use in recruitment studies. These results also indicate that using stone amenable to coral recruitment is unlikely to influence the wider benthic community.     

Risk Y-haplotypes and pathogenic variants of Arab-ancestry boys with autism by an exome-wide association study

Molecular Biology Reports - Autism is heterogeneous multifactorial neurodevelopmental and neuropsychiatric disorder with repetitive and limited behaviors as well as communication deficits....     

Bioleaching of Uranium From Egyptian Rocks Using Native Actinomycete Strains

Bioleaching is an economic, novel practice for extraction of metals from their sources by microorganisms. The current study aimed to extract uranium from Egyptian ores using native strains of actinomycetes. Two types of rocks and one ore sample were collected from west-central Sinai, Egypt. Major oxides of the samples and fourteen heavy metals, including uranium, were determined. X-ray diffraction analysis proved that uranium was present in the samples in various structures. Uranium was present in different concentrations, 220, 770, and 550 mg/kg in sandstone, granite, and manganese ore, respectively. Thirty-four actinomycete isolates were recovered from the studied samples using four different isolation media. Acid production capabilities were employed to select isolates for further leaching experiments. Bioleaching experiments were carried out using sterile and non-sterile ore samples. Using sterile ore samples, the highest solubilization percentages of U₃O₈ were 44.5, 38.55, and 16.76% from sandstone, manganese ore, and granite sample, achieved by isolates UA12, UA5, and U7, respectively. Lower solubilization percentages of U₃O₈ were recorded by using non-sterile ore samples. Investigating the factors affecting the bioleaching abilities of the tested organisms revealed that 10 days of incubation with 4% pulp density were the best conditions for U₃O₈ solubilization. The most efficient isolates were identified using 16S rRNA gene sequence analysis. UA12 identified to be Streptomyces bacillaris, while UA5 could not be identified, and U7 was assigned as uncultured bacterium clone. Scanning electron microscope examination of the bioleaching experiment showed different growth intensity within the active isolates. For larger-scale extraction purposes, a kilogram of sandstone, containing 220 mg of U₃O₈, was used in the form of a truncated cone in a heap leaching experiment. After 20 cycles, 14.72 mg/l (6.7%) of U₃O₈ was leached by S. bacillaris, while 19.36 mg/l (8.8%) of U₃O₈ was leached by chemical leaching using sulfuric acid. The results of this study prove that the extraction of uranium using actinomycetes could be exploited as less polluting, more economical, and more effective than traditional chemical extraction especially from low-grade ores or mining wastes.     

Effect of Ultrasound on Chromosomes of Lymphocyte Cultures

In-vitro experiments have been undertaken to assess the effect of ultrasound at diagnostic and therapeutic levels on chromosomes of human lymphocyte cultures. The frequency used was about 2 MHz. The intensity was that of diagnostic level, 23 mW/cm², which was increased stepwise to 3·5 W/cm². The time of exposure varied from two to eight hours. No difference could be detected between the numbers of cells with aberrations in the insonated and control cultures, but aggregation of red cells was observed at high intensities.     

Development of 2-oindolin-3-ylidene-indole-3-carbohydrazide derivatives as novel apoptotic and anti-proliferative agents towards colorectal cancer cells

Mitochondrial anti-apoptotic Bcl2 and BclxL proteins, are overexpressed in multiple tumour types, and has been involved in the progression and survival of malignant cells. Therefore, inhibition of such proteins has become a validated and attractive target for anticancer drug discovery. In this manner, the present studies developed a series of novel isatin–indole conjugates (7a-j and 9a-e) as potential anticancer Bcl2 and BclxL inhibitors. The progression of the two examined colorectal cancer cell lines was significantly inhibited by all of the prepared compounds with IC₅₀ ranges132–611 nM compared to IC₅₀ = 4.6 µM for 5FU, against HT-29 and IC₅₀ ranges 37–468 nM compared to IC₅₀ = 1.5 µM for 5FU, against SW-620. Thereafter, compounds 7c and 7g were selected for further investigations. Interestingly, both compounds exhibited selective cytotoxicity against both cell lines with high safety to normal fibroblast (HFF-1). In addition, both compounds 7c and 7g induced apoptosis and inhibited Bcl2 and BclxL expression in a dose-dependent manner. Collectively, the high potency and selective cytotoxicity suggested that conjugates 7c and 7g could be a starting point for further optimisation to develop novel pro-apoptotic and antitumor agents towards colon cancer.