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The Relationship Between Vegetation Type and Population Density-Diversity of Spiders in Certain Vegetable Crops
2023
Hamdi Abd El-Karim | Marguerite Rizk
The experiment was carried out on three different vegetable crops, Cucumber Cucumis sativus L. (Cucurbitaceae), eggplant Solanum melongena L. (Solanaceae) and okra Abelmoschus esculentus L. (Malvaceae), during summer 2021, to investigate the effect of vegetation type on spider density and diversity. For this study, the pitfall trap method was used to collect spiders from the soil surface to ensure a comprehensive representation of all spider guilds. During this study, 20 species belonging to 6 families were collected. The results showed that a total of 374, 285 and 194 individuals belonging to 18, 17 and 15 species were recorded in okra, cucumber and eggplant fields respectively. Species diversity was greater in okra cultivation. Results also indicated that the Lycosidae family was the most abundant and dominant, representing 71.75%, followed by the Linyphiidae family of 90 individuals representing 10.55% of the whole obtained population. The most dominant species were Wadicosa fidelis 152, 98 and 67 individuals and Pardosa injucunda 111, 69 and 52 individuals in okra, cucumber and eggplant respectively. It is inferred from this study that the type of plant can have an impact on spider communities.
Show more [+] Less [-]A Theoretical Analysis of the Plate Heat Exchanger's Ideal Operating Conditions for Producing Soybean Milk
2023
Omnia Salama | Manal Sorour | Ashrf Anwer | Mostafa Abd El-salam
Heat exchanger optimization is a very efficient thermal design inquiry. The goal of the research is to determine an optimal channel flow velocity as well as an optimal total plate number based on overall information on the effectiveness of employing chilled water to cool soybean milk. Heat transfer coefficient, Prandtl number, Reynolds number and pressure drop measurements were applied for milk and water. The rheological properties of soybean milk have been investigated at various temperatures (5, 10, 30, 50, 70 and 90 °C). The operational circumstances of PHE in soybean procedures were investigated at different numbers of plates, flow rates and flow velocities. Based on the present study, total substances showed non-Newtonian pseudoplastic conduct in any respect at any temperature and the power law model has a decent correlation. The cost estimation of the plate heat exchanger was observed at the lowest flow velocity of (2.25) m/s and number of plates is 17.
Show more [+] Less [-]Harvesting Microalgae by Chitosan as Sustainable Biopolymer
2023
Ola Obyd | Ayman Abou Hadid | Shawky Selim | Tarek El-Arabi
This study aimed to use the organic polymer, chitosan, as a flocculant for harvesting microalgae Chlorella. sp. Various polymer concentrations were tested. Within three min, 50 mg/L of chitosan showed the highest efficiency (98.9±0.5%), at pH 6.3, while the lowest efficiency (86.7±0.5%) was observed at pH 7.5. Harvesting efficiency in this study was chitosan concentration dependent. The present study showed that chitosan can be a promising and sustainable solution as an organic source and environmentally friendly flocculant. Additionally, it has excellent harvest productivity and requires minimum effort for quick outcomes.
Show more [+] Less [-]Isolation and Identification of Some Egyptian Ectomycorrhizal Sporocarps
2022
Aya Ahmed | Shawky Selim | Mona Zayed | Asmaa Ahmed | Dalia Abd El-Fattah
In contrast to the global countries, ectomycorrhizae members are not common in Egypt, however, they are very important in the afforestation of poor lands. Their occurrence in Pinus sp., Clerodendrum sp., and Eucalyptus sp. may help to explain why these trees are the most extensively dominant around the world, especially in Egypt. The identification and characterization of numerous ectomycorrhizal fungi often involve large morphological descriptions of sporocarps alone, which consequently, in some instances, raise arguments about the accuracy of these studies. The present work was achieved to isolate, identify, and characterize three ectomycorrhizal fungi from sporocarps combining morphological and molecular techniques. The morphological characteristics of tested species were assessed and compared to standard taxonomic literature. ITS-rDNA was utilized for molecular analysis using the universal fungal primers ITS1. Identification of these species was confirmed by comparing the sequences of amplified genomes of these species with respective species sequences in GenBank, followed by blast analysis.
Show more [+] Less [-]Element Composition and Toxicity of Seaweed Algae (Ulva lactuca, Laurencia obtuse and Padina pavonica) Toward Shrimp
2022
Ahmed Muhammad | Ibrahim Hassan | Manar Tawfeek | Hayam Ahmed Ibrahim
This study examined the macro and trace element contents as well as the cytotoxicity of Laurencia obtusa, Ulva lactuca, and Padina pavonica algae collected from the Mediterranean coast of Egypt (Alexandria coast). The results indicated that the seaweed samples contained high concentrations of Ca, Cl, Mg, K, Na, P and Fe. The Cu and Zn contents of the algae were in the ranges of 0.39-0.95 mg/100 g dw and 0.11-0.49 mg/100 g dw respectively. Fresh red algae contained the highest level of Zn and Cu, whereas the iodine level was 1.52, 1.27 and 1.01 mg/100g in fresh each of Padina pavonica, Laurencia obtuse and Ulva lactuca respectively. Fresh red, fresh green, dry green, dry red, in addition to fresh and dried brown algae had maximum lead (Pb) levels of 0.16, 0.14, 0.13, 0.12, 0.04 and 0.02 g/100 g respectively. Fresh red algae contained the highest Cd and Mn levels, whereas dried brown algae exhibited the lowest Cd and Mn concentrations. Different extracts of fresh and dried brown algae exhibited significant larvicidal activity against brine shrimp. LC50 values indicated that dry samples were more cytotoxic than fresh samples.
Show more [+] Less [-]Improvement of Growth and Productivity of Mango Trees Using Some Growth Stimulants under Salinity Conditions
2022
Fatma Abdalla | Hassan Elwakeel | Noha Mansour | Sabry Osman
A study was carried out in a mango orchard on reclaimed land for two seasons in 2019 and 2020. The experiment was implemented on fifteen years old mango trees “Fagri Kalan” budded on seedling mango rootstock and planted at 4 × 4 m. This experiment involved two soil growth stimulants (K humate, magnetite) and foliar application with cobalt. The experiment involved two factors, the first one was soil application with K humate by two levels (50 and 100 g/tree/year) and magnetite by two levels (250 and 500 g/tree /year) plus control, whereas the second factor was a foliar application with Co as cobalt sulfate by three levels (0, 15, and 30 ppm Co). The experiment was carried out in a factorial experiment in split plot design with three replicates whereas each replicate was represented by two trees. Result indicated that soil application with K humate at 100 g/tree followed by magnetite at 250 g/tree or foliar application with Co at 15 ppm alone or the combination between (K humate at 100 g/tree and cobalt at 15 ppm) gave the highest values of yield/tree, fruit weight, TSS, reducing sugars, leaf N, P, K, and Fe content of “Fagri Kalan” mango trees grown under salinity conditions.
Show more [+] Less [-]Utilization of Agro-Wastes for Bioethanol Production
2022
Sodaf Maan | Abdelwahab Abdelhafez | Asmaa Ahmed | Enas Hassan
Four agro-wastes were evaluated as substrates for bioethanol production. Seven of the pioneer isolates in the production of cellulase, xylanase and laccase enzymes were selected for soluble sugar and bioethanol production. The highest level of soluble sugar was produced on sugar beet pulp followed by corn cobs. The experimental design included using soybean okara and sesame husk as nitrogen sources added to the production medium. Extraordinary soluble sugar yields were obtained on sugar beet pulp or corn cobs in combination with soybean okara or sesame husk at the concentration of (0.3%) of either. Different concentrations of corn cobs or sugar beet (5, 10, 15, g/100 m medium) were mixed with optimal concentrations of nitrogen sources. Results showed that 10 g of sugar beet or corn cobs achieved the highest soluble sugar yield. The efficiency of four strains of S. cerevisiae for bioethanol production was investigated, S.cerevisiae (AUMC 14720) recorded the highest level of bioethanol on fermentable fungal broth after four days at 30°C.
Show more [+] Less [-]Effect of Variable Frequency Drive and Pipe Materials on Guava Juice Flow
2022
Shereen Shalaby | Mubarak Mustafa | Yahiya Heikal | Mahmoud El Attar
In this study, a designed variable frequency drive (VFD) was used to control a single-phase induction motor’s speed to pump guava juice at two solid concentrations (9°Bx and 11°Bx). Next, the pressure drop was measured in stainless-steel pipes of three diameters. The pressure drop percentage difference before and after using the VFD at varied flow rates with 10 repetitions at 5-minute intervals was evaluated. The pressure drop reduction range was 19.7%– 30.8% and 19.2 %–32.4% for the 9% and 11% solid concentrations respectively after using the VFD, which resulted in an average of 25.73% reductions in pressure drop and the pump’s total head and driving power. The rheological properties of guava juice were investigated at various temperatures (5, 15, 25, 35, 55 and 75°C). From the results, all materials exhibited non-Newtonian pseudoplastic behavior at all temperatures and concentrations, and correlated well with the power law model, with flow behavior index (n) values less than unity for the 9% and 11% solid concentrations. The findings offer helpful information for predicting how heat variations during processing influence the behavior of guava juice concentrates.
Show more [+] Less [-]Steroidal Saponins as Antioxidant and Alleviator of CCl4-Induced Oxidative Damage in Albino Rats
2022
Hala Eliwa | Mervat Ibrahim | Salwa EL-Sayed | Mohamed Abdelhamid
Liver toxicity is a common condition that can be induced by environmental pollutants. The present study explored the hepatoprotective activity of steroidal saponins extracted from the yam plant versus CC14-induced hepatotoxicity in albino rats. Twenty-five albino rats were classified into 5 groups. Rats of group (G1) were provided a basal diet and drinking water and served as un-treated controls. Other groups were administered CC14 orally twice a week at a dose of 400 mg/kg. The second group (G2) did not receive any further treatment and served as positive controls while rats in the groups G3, G4 and G5 were administered saponins (50,100 and 200 mg/kg body weight, respectively) for six weeks in the remaining groups. The hepatoprotective activity of saponins was assessed by measurement of liver enzymes, kidney function tests, malondialdehyde content, and antioxidant defense enzymes activities in serum of these rats. Saponins administration improved liver and renal function and significantly increased the activities of catalase, glutathione peroxidase (GSH-PX), glutathione reductase GSH-RD and superoxide dismutase SOD. These increases were linked to a considerable decrease in serum malondialdehyde levels, indicating that lipid peroxidation was being mitigated. Thus, the concentration of saponins (200 mg/kg) is the best concentration of protection against CC14-induced hepatic injury, improved liver and renal function, and reduced oxidative stress in rats.
Show more [+] Less [-]AquaCrop Model Enhancement under Soil Mulching Practices Considering Soil Temperature Effect
2022
Sobhy Mahmoud | Yasser Arafa | Ahmed Abo El-Hassan abdel aziz | Abdel-Ghany El-Gindy
Soil temperature under mulching conditions has a significant impact on crop development, growth rate and other parameters. However, it is not included in the AquaCrop model. Thus, this study aims to improve the AquaCrop model performance for better simulation of soil mulches by considering the heat changing under mulch materials. The proposed modification is conducted through AquaCrop-Open Source software to identify the differences between the temperatures under the mulched soil and air temperatures. It will also help to describe them as additional heat units in specific growth stages. The field data used to evaluate the proposed model has previously been used to calibrate and validate the AquaCrop model in simulating melon growth under different irrigation treatments and soil mulching practices. The results show that the proposed model performs better than the original model in simulating mulched melon under different irrigation regimes. The root mean square error of biomass values was reduced under the modified model by 40%-75% under different irrigation treatments. Additionally, the coefficient of determination (R2) of the modified model slightly increased from the original one. Thus, the proposed model provides a more reliable and robust model.
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