Numerical analysis of lean premixed combustor fueled by propane-hydrogen mixture

A numerical investigation of combustion of propane-hydrogen mixture in a swirl premixed micro gas turbine combustor is presented. The effects of hydrogen addition into propane on temperature distribution in the combustor, reaction rates of propane and hydrogen and NO, emissions for different equivalence ratios and swirl numbers are given. The propane-hydrogen mixture of 90/10% by volume was assumed. The numerical results and measurements of NO emissions for pure propane are compared. Excellent agreements are found for all equivalence ratios and swirl numbers, except for the highest swirl number (1.13). It is found that the addition of hydrogen into propane increases NO, emission. On the other hand, the increase of swirl number and the decrease of equivalence ratio decrease the NO, emissions

Effect of verapamil on glycemic control in type 2 diabetic hypertensive patients in Saudi Arabia : a quasi experimental study

Background: Type 2 diabetes is a common chronic disease that continues to increase in prevalence globally and is a major healthcare burden. Diabetes and hypertension frequently occur concurrently, and the use of antihypertensive agents is common in diabetic patients. One antihypertensive agent, verapamil, has tentatively shown potentially positive effects on glycemic control in assorted pre-clinical models. Aim: To evaluate the effect of verapamil on glycemic control in hypertensive type 2 diabetic patients. Methods: Type 2 diabetic hypertensive patients were recruited from King Fahad Medical City, Riyadh, KSA, to receive oral verapamil therapy. Blood pressure and glycometabolic parameters, including fasting plasma glucose (FPG), glycated hemoglobin (HbA1c), C-peptide, and homeostatic model assessment insulin resistance (HOMA-IR), were monitored at baseline and after 6 months of verapamil therapy. Results: Thirty-five patients (16 male, 19 female) with a mean age of 57.2 years were recruited. The use of verapamil was associated with non-significant decreases in HbA1c, FPG, C-peptide, and HOMA-IR. However, a sub-group of 17 participants showed a decrease in HbA1c that was ≥0.5%. Univariate logistic regression showed that baseline BMI, HOMA-IR, and C-peptide were significantly (P < 0.05) associated with HbA1c reductions of ≥0.5%. Conclusion: Verapamil is metabolically neutral and allows the stabilization of glycometabolic parameters in type 2 diabetic individuals. Additional research exploring the mechanism behind the variable response to verapamil therapy is warranted

Validation Of Endogenous Reference Genes For Relative Quantitation Studies Of Gene Expression In Nasopharyngeal Carcinoma

Reverse transcription real-time quantitative polymerase chain reaction (RT-qPCR) is a useful molecular contraption in translational biomedical research and clinical settings. RT-qPCR requires normalization. Housekeeping gene (HKG) as reference gene (RG) is commonly used for the relative quantification of the target gene (TG) in gene profiling assays. Normalization requires stably expressed endogenous RG. Recently, RGs were found to be regulated in a various experimental milieu in different tissues. Therefore, it is pertinent to identify HKGs that are stably expressed and are independent of factors influencing the cell. To validate 4 endogenous RGs for the relative quantification of TGs in gene expression analysis performed via RTqPCR in nasopharyngeal carcinoma. The qbase+ software utilizing geNorm analysis identified GAPDH, TBP and YARS as stably expressed HKGs. ACTB was the least stable RG in this study. The most suitable set of RG for NPC gene expression studies include GAPDH, TBP and YARS. No single gene was identified as the best RG for expression study. The RG that can be utilized during RT-qPCR on normal and malignant nasopharyngeal tissue samples is a collection of 3 genes (GAPDH, TBP and YARS) used as an average

CanVasc Consensus Recommendations for the Management of Antineutrophil Cytoplasm Antibody-associated Vasculitis: 2020 Update

Objective In 2015, the Canadian Vasculitis Research Network (CanVasc) created recommendations for the management of antineutrophil cytoplasm antibody (ANCA)-associated vasculitides (AAV) in Canada. The current update aimed to revise existing recommendations and create additional recommendations, as needed, based on a review of new available evidence. Methods A needs assessment survey of CanVasc members informed questions for an updated systematic literature review (publications spanning May 2014-September 2019) using Medline, Embase, and Cochrane. New and revised recommendations were developed and categorized according to the level of evidence and strength of each recommendation. The CanVasc working group used a two-step modified Delphi procedure to reach >80% consensus on the inclusion, wording and grading of each new and revised recommendation. Results Eleven new and 16 revised recommendations were created, and 12 original (2015) recommendations were retained. New and revised recommendations are discussed in detail within this document. Five original recommendations were removed, of which 4 were incorporated into the explanatory text. The supplementary appendix for practical use was revised to reflect the updated recommendations. Conclusion The 2020 updated recommendations provide rheumatologists, nephrologists, and other specialists caring for patients with AAV in Canada with new management guidance, based on current evidence and consensus from Canadian experts

The Role of Teachers' Digital Communication Skills in the Success of the Distance Learning Process in Private Universities in Lebanon

Purpose: This research study aims to examine the role of effective digital communication skills in the success of the distance learning process in the private universities in Lebanon. It also addresses the role of the teacher in motivating the students and acting as a facilitator to bridge the digital divide. Approach/Methodology/Design: To achieve the goal of this research, a descriptive approach was adopted. Six private universities were selected as a sample for the study and they were selected randomly. A questionnaire was developed as a tool for data collection. To verify the validity and reliability of the questionnaire, we used the Cronbach coefficient test (Cronbach's alpha). The researchers distributed 300 questionnaires to respondents from the selected private universities. Only 137 teachers responded, or (45.6%) of the total questionnaires distributed. For statistical analysis, the researchers used SPSS version 20.0. Findings: The results of the study revealed that private universities in Lebanon were ready to handle online teaching during the CoViD-19 pandemic. The respondents indicated their ability to handle the newly- emerging digital technologies to tackle crisis. It is found out that the arithmetic average rate related to the extent of the role that the teacher plays in the success of the distance learning process is (3.80)with a “strong” degree. The arithmetic average rate of the teacher's possession of the skill of effective communication was (3.69), with a “strong” degree. As for the teacher's role in the process of motivation, the average of the arithmetic mean was 3.59 with a “strong” degree, but it is closer to an “average” than to a “strong” degree. Practical Implications: The study presents various implications for different stakeholders; it principally addresses a crucial recent issue, and thus serves as a source for teachers and administrators. The results of the study open new venues for further research on online learning. Originality/value: The success of online learning is dependent on digital literacy. The familiarity with the new technological means that emerged during 2020 contributes to the succes

Novel Plant Regeneration and Transient Gene Expression in Catharanthus roseus

Catharanthus roseus genetic transformation represents a real challenge due, in part, to the lack of regeneration capability and this species’ recalcitrance to genetic transformation. In the present work, we demonstrate the regeneration of C. roseus plants from hypocotyls and cotyledons, using specific growth regulator conditions. Plants derived from hypocotyls and cotyledons were successfully acclimated and grown in the greenhouse. Furthermore, C. roseus meristem tissues were shown to have high shoot regeneration potential under conditions optimised for cotyledon- and hypocotyl-derived shooting. Meristem tissues were therefore investigated as a genetic transformation targets using both Agrobacterium tumefaciens and A. rhizogenes. Although meristem-derived shoots transformed with A. tumefaciens harbouring a p35S GUSplus construct revealed transient GUS expression and protein accumulation, they were not amenable to selection even after two months on selection medium. Transformation of C. roseus meristem tissues with A. rhizogenes resulted in a typical hairy root phenotype, in which the adventitious root tissue strongly expressed the p35S GUSplus construct, as revealed by intense GUS staining

Numerical analysis of lean premixed combustor fueled by propane-hydrogen mixture

A numerical investigation of combustion of propane-hydrogen mixture in a swirl premixed micro gas turbine combustor is presented. The effects of hydrogen addition into propane on temperature distribution in the combustor, reaction rates of propane and hydrogen and NOx emissions for different equivalence ratios and swirl numbers are given. The propane-hydrogen mixture of 90/10% by volume was assumed. The numerical results and measurements of NOx emissions for pure propane are compared. Excellent agreements are found for all equivalence ratios and swirl numbers, except for the highest swirl number (1.13). It is found that the addition of hydrogen into propane increases NOx emission. On the other hand, the increase of swirl number and the decrease of equivalence ratio decrease the NOx emissions