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Abstract Background Consonant clusters are a feature of many world languages. The acquisition of consonant clusters is one of the latest occurring aspects of speech acquisition in normally developing children. Difficulty producing consonant clusters has been found to contribute to high levels of unintelligibility in children with phonological impairment. This is a cross-sectional descriptive study that was applied on 150 typically developing (TD) Egyptian Arabic children, with an age range of 30 to 48 months, using the Egyptian Monosyllabic Consonant Cluster Test (EMCCT). The children were divided into 3 groups, each group with an age range of 6 months. The objective was to determine the age of suppression of cluster reduction and to evaluate two different phonological therapies (minimal contrast and auditory bombardment) in children who have not acquired consonant clusters (less than 90% correct production). Results Age of suppression of cluster reduction in Egyptian children was found to be between 3 years 6 months and 4 years. There was a gradual decrease in frequency of occurrence of cluster reduction from 74% (2 years 6 months–3 years) to 46% (3 years–3 years 6 months) to 10% (3 years 6 months–4 years). There was significant statistical association between consonant clusters of obstruents + sonorants (stops + sonorants and fricatives + sonorants) between the different age groups (p value < 0.001). Both techniques of therapy showed significant improvement of post-therapy score. There was no significant difference between total intervention duration in both techniques; however, there was significant association between cumulative intervention intensity and minimal contrast therapy (p value < 0.001). Conclusion The Egyptian Monosyllabic Consonant Cluster Test (EMCCT) is a valid and reliable assessment tool for identification of percentage of occurrence of cluster reduction process. Both minimal contrast and auditory bombardment approaches are applicable for cluster reduction remediation.

Huperzine A (HupA) is an anti‐Alzheimer's therapeutic and a dietary supplement for memory boosting that is extracted mainly from Huperziacae plants. Endophytes represent the upcoming refuge to protect the plant resource from distinction but their HupA yield is still far from commercialization. In this context, UV and gamma radiation mutagenesis of the newly isolated HupA‐producing Alternaria brassicae AGF041 would be applied in this study for improving the endophytic HupA yield. Compared to non‐irradiated cultures, UV (30–40 min, exposure) and γ (0·5 KGy, dose) irradiated cultures, each separately, showed a significant higher HupA yield (17·2 and 30·3%, respectively). While, application of a statistically optimized compound irradiation (0·70 KGy of γ treatment and 42·49 min of UV exposure, sequentially) via Response Surface Methodology (RSM) resulted in 53·1% production increase. Moreover, a stable selected mutant strain CM003 underwent batch cultivation using a 6·6 l bioreactor for the first time and was successful for scaling up the HupA production to 261·6 µg l−1. Findings of this research are demonstrated to be valuable as the employed batch fermentation represents a successful starting step towards the promising endophytic HupA production at an industrial scale. [ABSTRACT FROM AUTHOR]

GREEN synthetic strategies have been receiving a great interest for metal nanoparticles synthesis. In the current study, extracellular synthesis of silver nanoparticles (AgNPs) using the cell filtrate of the endophytic fungus, Alternaria tenuissima AUMC 13621 isolated from healthy leaves of Ruta graveolens plant, was achieved. The biosynthesized AgNPs were characterized by UV-visible spectroscopy, transmission electron microscopy (TEM), dynamic light scattering analysis (DLS), and fourier transform infra-red (FT-IR), The UV-visible spectrum shows a maximum absorption peak at 416nm. TEM photography showed the spherical shape of AgNPs with an average size 9.8nm. FT-IR indicates bounding of silver nanoparticles with the supernatant molecules of A. tenuissima and provides evidence for the presence of proteins and biomolecules responsible for reduction of Ag+ to Ag0, capping and stabilizing the synthesized AgNPs. Parametric optimization for the biosynthesis process showed maximum absorbance of 400-408nm at pH-12, 70oC using 1mM AgNO3 concentration. By studying the effect of gamma irradiation on AgNPs biosynthesis, the results showed that, the obtained peak became more sharper and narrower moreover, the absorbance intensity increased by increasing irradiation dose from 0.5 to 3.0kGy. The synthesized Ag NPs have a potent antimicrobial activity to some tested pathogenic bacterial strains and Candida albicans ATCC1023. Additionally, they had excellent free radical scavenging activity. The AgNPs antioxidant activity at 100μg/ml was of 65.99% inhibition that was close to the result obtained for ascorbic acid (67.39%). [ABSTRACT FROM AUTHOR]