155 research outputs found

    Extraction of certain heavy metals from sewage sludge using different types of acids

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    The removal of heavy metal from sludge before disposal or application to farmland is a necessary step to achieve a more safe sludge usage or disposal. Chemical extraction using inorganic acids (nitric, hydrochloric) and organic acids (citric, oxalic) were tested for extraction of chromium, copper, nickel, lead and zinc from contaminated sewage sludge at different pH and reaction time. Results revealed that solubilization of metals using inorganic acids achieved its maximum extraction efficiency (Cr-88%, Cu-82%, Ni-86%, Pb-94%, Zn-89%) at pH value lower than 2 and acid contact times of 1hour. while in case of organic acids oxalic acid does not show good results comparing to citric acid that at pH 2.43 citric acid seemed to be highly effective in extracting Cu (86%), Zn(88%), mostly after 1 day of extraction time, Cr (90%), Ni (96%) at 5 days leaching time, while Pb(85%) removal at the same pH was at a longer leaching time 10 days. At pH 3, citric acid seemed to be also highly effective in extracting Cr (66%), Cu(48%), Pb (66%), Zn(69%) at 1 day, while higher removal was also attained for Ni(68%) at only 4 h leaching time. Finally the extraction efficiencies of citric acid for Cr, Cu, Ni, Pb, Zn, are high enough to reduce the heavy metal content in sludge to levels below the legal standards

    Simulation of Single and Twin Impinging Jets in Cross-flow of VTOL Aircrafts (Review)

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    When operating near the ground beneath a Vertical/Short Take-Off and Landing (VSTOL) aircraft a complex turbulent 3D flow is generated. This flow field can be represented by the configuration of twin impinging jets in a cross-flow. Studying these jets is a significant parameter for the design of VTOL aircraft. This flowfield during very low speed or hover flight operations is very complex and time dependent. An important number of experimental researches and simulations have been carried out to be able to understand much better these flows related with powered lift vehicles. Computational Fluid Dynamics (CFD) approach will be used in this paper work for simulation purposes of a single and twin impinging jet through and without crossflow

    Green Synthesis of Zinc Oxide Nanoparticles from Althaea officinalis Flower Extract Coated with Chitosan for Potential Healing Effects on Diabetic Wounds by Inhibiting TNF-α and IL-6/IL-1β Signaling Pathways

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    Sammar Fathy Elhabal,1 Nashwa Abdelaal,2 Saeed Abdul Kareem Saeed Al-Zuhairy,3 Mohamed Fathi Mohamed Elrefai,4,5 Ahmed Mohsen Elsaid Hamdan,6 Mohamed Mansour Khalifa,7 Sandra Hababeh,8 Mohammad Ahmad Khasawneh,9 Gehad M Khamis,10 Jakline Nelson,11 Passant M Mohie,10 Rania A Gad,12 Amira Rizk,13 Soad L Kabil,14 Mohamed Kandeel El-Ashery,15,16 Bhaskara R Jasti,17 Nahla A Elzohairy,18,19 Tayseer Elnawawy,20 Fatma E Hassan,21,22 Mohamed A El- Nabarawi23 1Department of Pharmaceutics and Industrial Pharmacy, Faculty of Pharmacy, Modern University for Technology and Information (MTI), Mokattam, Cairo, Egypt; 2Department of Integrative Physiology, Baylor College of Medicine, Houston, TX, USA; 3Department of Pharmacy, Kut University College, Kut, Wasit, Iraq; 4Department of Anatomy, Histology, Physiology and Biochemistry, Faculty of Medicine, The Hashemite University, Zarqa, Jordan; 5Department of Anatomy and Embryology, Faculty of Medicine, Ain Shams University, Cairo, Egypt; 6Department of Pharmacy Practice, Faculty of Pharmacy, University of Tabuk, Tabuk, Saudi Arabia; 7Department of Human Physiology, Faculty of Medicine, Cairo University, Cairo, Egypt; 8Department of Pharmaceutics, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia; 9Department of Chemistry, College of Science U.A.E. University, Al-Ain, United Arab Emirates; 10Department of Clinical Pharmacology, Faculty of Medicine, Alexandria University, Alexandria, Egypt; 11Department of Microbiology and Immunology, Faculty of Pharmacy, Nahda University, Beni-Suef, Egypt; 12Department of Pharmacology and Toxicology, Faculty of Pharmacy, Nahda University, Beni-Suef, Egypt; 13Food Science and Technology Department, Faculty of Agricultural, Tanta University, Tanta, Egypt; 14Department of Clinical Pharmacology, Faculty of Medicine, Zagazig University, Zagazig, Egypt; 15Pharmaceutical Chemistry Department, Faculty of Pharmacy, Cairo University, Cairo, Egypt; 16Medicinal Chemistry Department, Faculty of Pharmacy, King Salman International University, Ras-Sedr, South Sinai, Egypt; 17Department of Pharmaceutics and Medicinal Chemistry, Thomas J. Long School of Pharmacy, University of the Pacific, Stockton, CA, USA; 18Air Force Specialized Hospital, Cairo, Egypt; 19Department of Microbiology and Immunology, Faculty of Pharmacy, Modern University for Technology and Information (MTI), Mokattam, Cairo, Egypt; 20Department of Pharmaceutics, Egyptian Drug Authority, Cairo, Egypt; 21Medical Physiology Department, Faculty of Medicine, Cairo University, Giza, Egypt; 22General Medicine Practice Program, Department of Physiology, Batterjee Medical College, Jeddah, Saudi Arabia; 23Department of Pharmaceutics and Industrial Pharmacy, Faculty of Pharmacy, Cairo University, Cairo, EgyptCorrespondence: Sammar Fathy Elhabal, Email [email protected]; [email protected]; Mohamed A El- Nabarawi, Email [email protected]: Diabetes Mellitus is a multisystem chronic pandemic, wound inflammation, and healing are still major issues for diabetic patients who may suffer from ulcers, gangrene, and other wounds from uncontrolled chronic hyperglycemia. Marshmallows or Althaea officinalis (A.O.) contain bioactive compounds such as flavonoids and phenolics that support wound healing via antioxidant, anti-inflammatory, and antibacterial properties. Our study aimed to develop a combination of eco-friendly formulations of green synthesis of ZnO-NPs by Althaea officinalis extract and further incorporate them into 2% chitosan (CS) gel.Method and Results: First, develop eco-friendly green Zinc Oxide Nanoparticles (ZnO-NPs) and incorporate them into a 2% chitosan (CS) gel. In-vitro study performed by UV-visible spectrum analysis showed a sharp peak at 390 nm, and Energy-dispersive X-ray (EDX) spectrometry showed a peak of zinc and oxygen. Besides, Fourier transforms infrared (FTIR) was used to qualitatively validate biosynthesized ZnO-NPs, and transmission electron microscope (TEM) showed spherical nanoparticles with mean sizes of 76 nm and Zeta potential +30mV. The antibacterial potential of A.O.-ZnO-NPs-Cs was examined by the diffusion agar method against Gram-positive (Staphylococcus aureus and Bacillus subtilis) and Gram-negative bacteria (Escherichia coli and Pseudomonas aeruginosa). Based on the zone of inhibition and minimal inhibitory indices (MIC). In addition, an in-silico study investigated the binding affinity of A.O. major components to the expected biological targets that may aid wound healing. Althaea Officinalis, A.O-ZnO-NPs group showed reduced downregulation of IL-6, IL-1β, and TNF-α and increased IL-10 levels compared to the control group signaling pathway expression levels confirming the improved anti-inflammatory effect of the self-assembly method. In-vivo study and histopathological analysis revealed the superiority of the nanoparticles in reducing signs of inflammation and wound incision in rat models.Conclusion: These biocompatible green zinc oxide nanoparticles, by using Althaea Officinalis chitosan gel ensure an excellent new therapeutic approach for quickening diabetic wound healing. Keywords: wound healing, antimicrobial, antioxidant, Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa, chitosan, wound concentration, wound incisio

    Oxidative stress in pregnancy and fertility pathologies

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    Oxidative stress designates the state of imbalance between reactive oxygen species (ROS) production and antioxidant levels. In a healthy placenta, there is an increase in ROS production, due to formation of new tissues and inherent metabolism, but this is balanced by higher levels of antioxidants. However, this balance is lost in some situations, with a consequent increase in oxidative stress levels. Oxidative stress has been implicated in several placental disorders and pregnancy pathologies. The present review intends to summarize what is known about the relationship between oxidative stress and well-known pregnancy disorders

    Minimally invasive surgery and cancer: controversies part 1

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    Perhaps there is no more important issue in the care of surgical patients than the appropriate use of minimally invasive surgery (MIS) for patients with cancer. Important advances in surgical technique have an impact on early perioperative morbidity, length of hospital stay, pain management, and quality of life issues, as clearly proved with MIS. However, for oncology patients, historically, the most important clinical questions have been answered in the context of prospective randomized trials. Important considerations for MIS and cancer have been addressed, such as what are the important immunologic consequences of MIS versus open surgery and what is the role of laparoscopy in the staging of gastrointestinal cancers? This review article discusses many of the key controversies in the minimally invasive treatment of cancer using the pro–con debate format

    The dynamic geophysical environment of (101955) Bennu based on OSIRIS-REx measurements

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    The top-shaped morphology characteristic of asteroid (101955) Bennu, often found among fast-spinning asteroids and binary asteroid primaries, may have contributed substantially to binary asteroid formation. Yet a detailed geophysical analysis of this morphology for a fast-spinning asteroid has not been possible prior to the Origins, Spectral Interpretation, Resource Identification, and Security-Regolith Explorer (OSIRIS-REx) mission. Combining the measured Bennu mass and shape obtained during the Preliminary Survey phase of the OSIRIS-REx mission, we find a notable transition in Bennu’s surface slopes within its rotational Roche lobe, defined as the region where material is energetically trapped to the surface. As the intersection of the rotational Roche lobe with Bennu’s surface has been most recently migrating towards its equator (given Bennu’s increasing spin rate), we infer that Bennu’s surface slopes have been changing across its surface within the last million years. We also find evidence for substantial density heterogeneity within this body, suggesting that its interior is a mixture of voids and boulders. The presence of such heterogeneity and Bennu’s top shape are consistent with spin-induced failure at some point in its past, although the manner of its failure cannot yet be determined. Future measurements by the OSIRIS-REx spacecraft will provide insight into and may resolve questions regarding the formation and evolution of Bennu’s top-shape morphology and its link to the formation of binary asteroids
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