Simulation And Optimization Of Waste Heat To Electricity Through Organic Rankine Cycles (ORCs): A Case Study In An Oil Refinery

Energy efficiency has become a global problem that is detrimental to the chemical industries technically, economically and to the environment. Organic Rankine Cycle (ORC) is a promising technology that can solve this problem by recovering heat from low-grade waste heat sources by using organic working fluids. The heat source for the ORC system used in this article is air leaving air coolers in an oil refinery with a temperature of 140o C. The heat exchanger data for this refinery was used in the simulation of a basic cycle and a regenerative cycle using ASPEN HYSYS V.10. These ORC systems were simulated using hydrocarbons, refrigerants, and alternative refrigerants as the working fluids to compare their performance at three different condensation temperatures which are 15o C, 35o C, and 50o C. The system was optimized using the HYSYS optimizer to reach the optimum conditions for each working fluid. Results of this study have proven that the alternative working fluids R1234ze (Z) and R1224yd (Z) perform very well when compared to hydrocarbon working fluids and outperform the regular refrigerants. For the basic cycle which yielded the optimum results, R1234ze (Z) produced 1258.90 kW of turbine work and has a thermal efficiency of 11.31%. Hence, they are promising working fluids and are highly recommended to be used in the future since they perform highly economically in addition to being environmentally friendly

Cyanobacteria—From the Oceans to the Potential Biotechnological and Biomedical Applications

Cyanobacteria are photosynthetic prokaryotic organisms which represent a significantsource of novel, bioactive, secondary metabolites, and they are also considered an abundant source ofbioactive compounds/drugs, such as dolastatin, cryptophycin 1, curacin toyocamycin, phytoalexin,cyanovirin-N and phycocyanin. Some of these compounds have displayed promising results insuccessful Phase I, II, III and IV clinical trials. Additionally, the cyanobacterial compounds applied tomedical research have demonstrated an exciting future with great potential to be developed into newmedicines. Most of these compounds have exhibited strong pharmacological activities, includingneurotoxicity, cytotoxicity and antiviral activity against HCMV, HSV-1, HHV-6 and HIV-1, so thesemetabolites could be promising candidates for COVID-19 treatment. Therefore, the effective large-scale production of natural marine products through synthesis is important for resolving the existingissues associated with chemical isolation, including small yields, and may be necessary to betterinvestigate their biological activities. Herein, we highlight the total synthesized and stereochemicaldeterminations of the cyanobacterial bioactive compounds. Furthermore, this review primarilyfocuses on the biotechnological applications of cyanobacteria, including applications as cosmetics,food supplements, and the nanobiotechnological applications of cyanobacterial bioactive compoundsin potential medicinal applications for various human diseases are discussed.Stockholm UniversityPeer Reviewe

Feasibility of cyclic and continuous steam injections into a Middle-Eastern heavy oil reservoir: A simulation approach

[abstract not available

Implementation and validating transcutaneous bilirubinometry for neonates

During the first week of life all newborns have increased bilirubin levels by adult standards, with approximately 60% of term babies and 85% of preterm having visible jaundice. A significant reduction in serum bilirubin analysis which is traumatic and painful, could be achieved after implementation of transcutaneous bilirubin (TCB) measurements in preterm babies. Measurements made on the forehead and sternum have the best correlation with TSB. Objectives: Is to evaluate the use of non-invasive transcutaneous spectrophotometer, its efficiency and the influence of the site of measurement of transcutaneous bilirubin (forehead and sternum) on the accuracy of bilirubin levels. Subjects and methods: This study was conducted on 316 clinically jaundiced neonates in NICU and post-natal clinics of Ain-Shams University Hospital, El Monira Governmental Public Hospital and El Amreky Private Hospital. Neonates of both sexes and gestational age ⩾30 weeks were included, with no hemolytic disease, no known skin disorders or receiving phototherapy or exchange transfusions. Transcutaneous bilirubin using Minolta JM-103 probe from sternum and forehead was measured and compared to serum bilirubin levels. Results: There was statistically significant correlation between TSB and TCB in all the groups of studied cases, but was slightly higher in the cases with bilirubin measured in postnatal age of ⩽3 days. In preterm newborns, measurement of TCB from forehead was less accurate than from sternum. Conclusion: Noninvasive TCB measurement by Minolta JM-103 has demonstrated significant accuracy compared to TSB measured by clinical laboratory methods in all cases with better accuracy in cases of IHB. TCB measurement over sternum is more accurate than forehead

Helioplis Residence

الغرض من هذا الكتاب هو اعطاؤ القاري فكرة جيدة عن كيفية إدارة المشاريع الانشائية من خلال شرح مبسط وأمثلة من موقع المشروع لكي يفهم القارئ كيفية عمل إدارة ناجحة وهذا الكتاب ليس فقط للمهندسين والاستاتذة المتخصصين في الهندسة المدنية فقط ولكن يستطيع القارئ العادي ان يفهم معنى الادارة بصورة سهلة وبسيطة ويتكون الكتاب من عدة ابواب وتم شرحهم بالتدرج الموضوعى عن مشروع إسكان اعضاء نادي هليوبولس الرياضي. ففي الباب الأول يتم وصف المشروع الذي سوف يتناول الكتاب شرح كل شيئ فيه في الأبواب القادمة والباب الثاني يشرح العقد المتفق عليه في المشروع والتعليق المناسب عليه والباب الثالث يوضح الهيكلة الإدارية للمشروع والمسؤليات لكل العامليين. الباب الرابع يشرح لكيفية عمل تقدير التكلفة بطريقة رياضية في صورة جداول وفي الباب السابع يوضح كيفية عمل تخطيط المشروع وعمل جدولة له عن طريق الحاسب الآلي والباب الثامن يوضح التضفق النقدي للمشروع والباب التاسع يشرح كيفية عمل إدارة للموارد والباب العاشر يشرح طريقة تنفيذ المشروع بصورة مبسطة في شكل صور والباب الحادي عشر يوضخ كيفية عمل مراقبة للجودة في المشروع والباب الثاني عشر يوضح كيفية مراقبة زمن وتكلفة المروع والباب الثالث عشر يشرح ما هوة ‘ادرة الأمان في المشروعات الإنشائية وأخيرا وليس اخرا الباب الرابع عشر يشرح كيفية إدارة المخاضر في المشرو

Juvenile lupus: Different clinical and serological presentations compared to adult lupus in Egypt

Aim of the work: We aimed to evaluate the differences in clinical presentation, serological pattern and disease activity between juvenile and adult-onset of Egyptian systemic lupus erythematosus (SLE) patients. Patients and methods: 160 Egyptian SLE patients (80 Adult-onset and 80 juveniles) were included. Patients records were reviewed for clinical and laboratory evaluation on presentation. Disease activity at onset was assessed using SLE Disease Activity Index (SLEDAI). Results: The mean age of the adult patients was 29.9 ± 7.2 years and of the juvenile cases (12.8 ± 2.1 years). The female:male ratio of the adults was 10:1 while it was 39:1 in the SLE children. The most common clinical presentation among adult SLE was malar rash (75%) followed by articular manifestations (62.5%), while in juveniles, nephritis (78.8%) followed by articular manifestations (71.2%) were the most common. Juvenile patients had more frequent neuropsychiatric (p = 0.015) and hematologic abnormalities (p < 0.001) at onset; and lupus nephritis (72.5%) compared to adults (36.2%) (p < 0.001) during the first year of presentation. Juvenile SLE showed higher frequency of proteinuria (p < 0.001), hematuria (p = 0.02) and active urinary sediments (p = 0.016). Proliferative nephritis was the most common form among both juveniles and adults. Positivity and titres of both anticardiolipin antibodies and lupus anticoagulant were significantly higher in juvenile SLE. Juvenile SLE patients had significantly higher SLEDAI [median (IQR): 12 (10–22)] compared to adults [median (IQR): 8 (4–12)], p < 0.001. Conclusion: Juvenile SLE patients differ from adult SLE with more frequent major organs affection and significantly higher serological activity. Earlier and more careful assessment with strict management plan and follow-up are needed in juvenile SLE patients

Targeting Cancer Stem Cells as the Key Driver of Carcinogenesis and Therapeutic Resistance

The emerging concept of cancer stem cells (CSCs) as the key driver behind carcinogenesis, progression, and diversity has displaced the prior model of a tumor composed of cells with similar subsequently acquired mutations and an equivalent capacity for renewal, invasion, and metastasis. This significant change has shifted the research focus toward targeting CSCs to eradicate cancer. CSCs may be characterized using cell surface markers. They are defined by their capacity to self-renew and differentiate, resist conventional therapies, and generate new tumors following repeated transplantation in xenografted mice. CSCs’ functional capabilities are governed by various intracellular and extracellular variables such as pluripotency-related transcription factors, internal signaling pathways, and external stimuli. Numerous natural compounds and synthetic chemicals have been investigated for their ability to disrupt these regulatory components and inhibit stemness and terminal differentiation in CSCs, hence achieving clinical implications. However, no cancer treatment focuses on the biological consequences of these drugs on CSCs, and their functions have been established. This article provides a biomedical discussion of cancer at the time along with an overview of CSCs and their origin, features, characterization, isolation techniques, signaling pathways, and novel targeted therapeutic approaches. Additionally, we highlighted the factors endorsed as controlling or helping to promote stemness in CSCs. Our objective was to encourage future studies on these prospective treatments to develop a framework for their application as single or combined therapeutics to eradicate various forms of cancer