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Abstract The River Nile is the artery of Egypt, as it presents more than 96% of the municipal, industrial, and irrigation necessities of Egypt. This study was dedicated to providing data about the effect of pollution at six stations on the River Nile at the Rosetta branch during the period from August 2019 to April 2020, using heavy metals analysis and zooplankton as biological indicators. It was found that the average of heavy metals concentration follows the descending order Al > Fe > Mn > Zn > Ni > Co. Most of the heavy metals recorded its highest values at El-Rahawy station. Zooplankton community was represented by 32 species in addition to 4 Meroplanktons. Five groups of zooplankton were recorded, viz. Rotifera (1717 org./L), Protozoa (552 org./L), Cladocera (54 org./L), Nematoda (46 org./L), and other Meroplankton (44 org./L), dominated by Rotifera followed by Protozoa, Cladocera, Nematoda, and other Meroplanktons contributing 71%, 23%, 2%, 2%, and 2%, respectively. The highest average density of total zooplankton was recorded during spring while the lowest was recorded during summer. The highest similarity of (79.12%) was observed between (Site 1) and (Site 5). Almost all diversity indices were conducted and showed its highest values in site 6. The principal component analysis conducted between heavy metals, and zooplankton showed a significant negative correlation was shown for the dominant zooplankton with the heavy metals except with cobalt. Nematoda and the rotifer Brachionus angularis recorded a positive correlation with heavy metals except cobalt.

Controlled-release technology was introduced to offer an incredible guarantee for improving the adequacy of the existing active molecules and solving the related environmental troubles. Our study attempts to utilize the controlled release of alginate niclosamide-l-glutamate formulation to control Schistosoma mansoni intermediate host (Biomphalaria alexandrina snail) and to evaluate the amount of niclosamide released in relation to its attraction and mortality rate. Results: polymeric formulations B3-4b at a concentration of 0.3 ppm niclosamide in combination with 75% l-glutamate caused 100% mortality of B. alexandrina snails 5-day post-exposure. Stable snails mortality rates were obtained post-exposure to polymer B3-4a (R2 = 0.9823). The high potential of the polymeric formulations B3-4a (0.2 ppm niclosamide and 75% l-glutamate) to attract snail toward polymer direction was manifested by 80%, 14%, 6% and 0% snail in areas (I), (II), (III) and (IV), respectively 24-hr post-exposure. While, B3-4a showed a high mortality rate of attracted snails resembled by 40% and 100% on the 2nd and 7th days, respectively. The modified structure of polymer-niclosamide-l-glutamate prolonged the validity and efficiency of the niclosamide. Slowly released molluscicide was effective at lower concentrations with increasing concentrations of the applied attractant that could reduce its toxicity to the water ecosystem. Keywords: Biomphalaria alexandrina, Control of schistosomiasis, Controlled release molluscicides, l-glutamate attractant, Niclosamide

Starch content is one of the major quality criteria targeted by potato breeding programs. Traditional potato breeding is a laborious duty due to the tetraploid nature and immense heterozygosity of potato genomes. In addition, screening for functional genetic variations in wild relatives is slow and strenuous. Moreover, genetic diversity, which is the raw material for breeding programs, is limited due to vegetative propagation used in the potato industry. Somaclonal variation provides a time-efficient tool to breeders for obtaining genetic variability, which is essential for breeding programs, at a reasonable cost and independent of sophisticated technology. The present investigation aimed to create potato somaclones with an improved potential for starch accumulation. Based on the weight and starch content of tubers, the somaclonal variant Ros 119, among 105 callus-sourced clones, recorded a higher tuberization potential than the parent cv Lady Rosetta in a field experiment. Although this somaclone was similar to the parent in the number of tubers produced, it exhibited tubers with 42 and 61% higher fresh and dry weights, respectively. Additionally, this clone recorded 10 and 75% increases in starch content based on the dry weight and average content per plant, respectively. The enhanced starch accumulation was associated with the upregulation of six starch-synthesis-related genes, namely, the AGPase, GBSS I, SBE I, SBE II, SS II and SS III genes. AGPase affords the glycosyl moieties required for the synthesis of amylose and amylopectin. GBSS is required for amylose elongation, while SBE I, SBE II, SS II and SS III are responsible for amylopectin.

Advancements in shoot regeneration systems support biotechnology-based tools used in the genetic improvement of plant crops. This study aims to enhance shoot regeneration in potatoes by boosting polyamine content by adding AgNO3 to the shoot regeneration medium (MS medium supplemented with 30 g L−1 sucrose, 100 mg L−1 myoinositol, and 2.25 BA mg L−1). Five concentrations of AgNO3 (2, 4, 6, 8, and 10 mg L−1) were used in addition to a control. The effect of AgNO3 on regeneration assumed a more or less concentration-dependent bell-shaped curve peaking at 4 mg L−1. Enhancements in shoot regeneration were attributed to the known role of AgNO3 as an ethylene action blocker in addition to improvements in polyamine accumulation without an increase in H2O2 content, lipid peroxidation, or DNA damage. The uncoupling of shoot regeneration and polyamine content recorded at high AgNO3 concentrations can be attributed to the consumption of polyamines to counteract the synchronized oxidative stress manifested by increases in H2O2 content, lipid peroxidation, and DNA damage.

Abstract Background Comparative analysis of essential amino acids and fatty acid of enriched and unenriched Artemia spp. collected from Wadi El Natrun, Elbeheira, Egypt, was investigated. Results The obtained results indicated that Leucine recorded the highest concentration (17.22%, 11.4%) in unenrichment A. tunisiana and A. franciscana, respectively followed by arginine (10.31%, 9.6%); however, glutamic acid recorded the lowest concentration (0.05%) in A. tunisiana. Statistical analysis showed no significant differences in some amino acid concentrations (P

Abstract Background Heterophyiasis is an intestinal sickness promoted by infection with the heterophyid digenetic worms. It is one of the major infectious diseases of public health in the developing countries. Method Single-cell gel eletrophoresis, or comet assay, was carried out for detecting DNA damage in the digestive gland cells of Pirenella conica infected with Heterophyes larvae. Besides, apoptosis, some isoenzymes, and two biogenic amines (neurotransmitters) were investigated using the flow cytometric analysis, the starch gel electrophoresis, and the HPLC techniques respectively. Snails were collected from brackish water area around Port Said province during the spring–summer periods of 2012–2013. Results The results showed that infection with the larval trematodes increased tail length (length of DNA migration) in the digestive gland cells of infected snails. Meanwhile, the percentage of apoptosis was significantly elevated (58.80%) in the snails infected with the larval trematodes as compared to that of uninfected snails (39.59%). Apparent polymorphism was detected in the four enzymes obtained from the digestive gland extracts. Conclusion DNA damage and increase of apoptosis in the digestive glands of infected snails may end up with a decrease of 5-HT (serotonin) and DA (dopamine) concentrations in all tissues through the course of infection.

Procambarus clarkii juveniles were used as an aquatic model to investigate growth performance and immune parameters after 6 weeks of feeding with supplementation of ten experimental diets containing 1%, 2%, 3% Biogen® (as probiotics), Allium sativum (garlic) and Cynodon dactylon (as immunostimulant) and one concentration (3 g/L) of sodium alginate (as prebiotics), compared with feeding on control basal diets only. All supplementation diets increased survival rates and wet weight, while, 1% and 2% C. dactylon showed a significant (P ⩽ 0.05) increase in weight gain percentage (WG%), and specific growth rate (SGR). Feeding with diet containing 2% Biogen®, 2% and 3% garlic and sodium alginate showed a significant (P ⩽ 0.05) increase in SGR rate after 6 weeks. Synergetic effect of 1% and 3% Biogen® and sodium alginate in total hemocytes count (THC) which increased significantly (P ⩽ 0.05) after 6 weeks of feeding. Prophenoloxidase activity increased with all supplemented diets. While SOD increased significantly with 3% C. dactylon, 1% and 3% garlic and 2% Biogen. The results indicated that Biogen®, garlic, C. dactylon and sodium alginate inclusion with a basal diet had the potential to improve the growth and immune response of P. clarkii juveniles, hence this enables us to use the three supplementation diets in fish and prawn farms to improve their growth and immune parameters.

THIS STUDY aimed to establish functional SSR markers corresponding to variations in starch accumulation in potato somaclones. In addition to the original cultivar Lady Rosetta, fourteen callus-sourced somaclones were investigated for their starch and sugar contents as well as dry matter content. Of the selected somaclones, one represented clones with the same starch content of the original cultivar and another represented those of lower starch content. The remaining somaclones have higher starch content, compared with original cultivar. The combined results of two growing seasons unveiled significant positive correlation between dry matter content and starch content which was absent when replacing starch with soluble sugars. Insignificant correlations were recorded between sugar content and starch content. Based on the transferability of SSR markers between species, six SSR primers characterizing variation in starch accumulation in sweet potatoes were exploited to assess genetic diversity among the selected potato clones. The analysis generated distinct and reproducible banding patterns with 68 bands, of which 62 were polymorphic. The utilized primers reflected high resolving power appeared in PIC of 0.457 in average and amplification of 44 unique bands, distributed in all studied clones except one of those containing higher starch content, compared with the original cultivar. This fingerprint is a prerequisite for recruiting clones with distinguished starch accumulation potential, addressed in the present study, in breeding programs targeting the improvement of starch accumulation in potato tubers. On the other hand, the utilized primers failed to establish phylogenetic relationship corresponding to starch content of the addressed clones. This may be attributed to utilization of few primers that did not cover a considerable proportion of the addressed genome. [ABSTRACT FROM AUTHOR]

The goal of this research study is to examine, through the finite element method, the efficiency of using two-dimensional (2D) functionally graded materials (FGMs) in lowering the elastic/thermoelastic stresses acting on cylinders. In 2D-FGMs, the properties are assumed to vary in the radial and tangential directions simultaneously, which is rarely investigated in the literature. The cylinder is subjected to asymmetric inner normal traction with/without asymmetric thermal loading. For the considered case studies, results revealed that 2D-FGMs is beneficial compared to the conventional grading. In case of considering mechanical load only, the tangential stress declines by almost 39%. Similarly, accounting for thermomechanical load resulted in radical falls for the tangential and axial stresses by around 63% and 61%, respectively. Accordingly, the von Mises stress declines dramatically with different values allowing for safe load escalation, and enhancing the cylinder's durability. Finally, no certain values for the used tangential function's parameters are preferred to have maximum reduction of stresses under all working circumstances, which necessitates performing optimization. [ABSTRACT FROM AUTHOR]