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1.
Heliyon ; 9(9): e19562, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37809797

ABSTRACT

Combined Cycle Power Plants (CCPP) are an effective method for Power generation due to their high thermal efficiency, low fuel consumption, and low greenhouse emissions. However, investing millions into building a power plant without knowledge of the power generation capacity seems unproductive. With the help of AI, we have tried to eliminate this conundrum. The present study focuses on the prediction of power produced by a 747 MW Combined Cycle Power Plant (CCPP) using a Back Propagation Neural Network (BPNN) and compares its results with the actual data from CCPP. BPNN is a regression-based prediction technique that is utilized in this study to develop a predictive model and train it using the following input features: Ambient Temperature, Ambient Pressure, Mass Flow rate of fuel in Gas Turbine 1, and Mass Flow rate of fuel in Gas Turbine 2. The Predictive Model with 10 neurons in the hidden layer was found to be most effective with Mean Squared Error (MSE) value, for the validation dataset, of 0.0063237. CCPP is also analyzed through a thermodynamic model, developed using EES. A detailed energy analysis is carried out and the results were compared with predicted and actual data. It was found that the thermal efficiency and total power generation of actual, predicted, and simulated models were 27.541% & 667.32 MW, 28.238% & 683.48 MW and 28.201% & 683.16 MW, respectively. A parametric study was further carried out to investigate the significance of operating parameters on power output and it was concluded that the temperatures across the Gas turbines have a significant impact on the performance of CCPP. Finally, Methane was replaced by 3 different fuels, one by one, and the effect of each fuel was investigated thermodynamically. It was found that the Lower Heating Value (LHV) of fuel was an important parameter in achieving a higher power output. It can be summarized from this research work that predictive models do have accuracy and such data science techniques can be used as a substitute for extensive thermodynamic calculations.

2.
BMC Public Health ; 23(1): 1045, 2023 06 01.
Article in English | MEDLINE | ID: mdl-37264348

ABSTRACT

BACKGROUND: Most young adults and adolescents in the United Arab Emirates (UAE) do not meet the established internationally recommended physical activity levels per day. The Arab Teen Lifestyle Study (ATLS) physical activity questionnaire has been recommended for measuring self-reported physical activity of Arab adolescents and young adults (aged 14 years to mid-twenties). The first version of the ATLS has been validated with accelerometers and pedometers (r ≤ 0.30). The revised version of the questionnaire (ATLS-2, 2021) needs further validation. The aim of this study was to validate the self-reported subjective sedentary and physical activity time of the ATLS-2 (revised version) physical activity questionnaire with that of Fibion accelerometer-measured data. METHODS: In this cross-sectional study, 131 healthy adolescents and young adults (aged 20.47 ± 2.16 [mean ± SD] years (range 14-25 years), body mass index 23.09 ± 4.45 (kg/m2) completed the ATLS-2 and wore the Fibion accelerometer for a maximum of 7 days. Participants (n = 131; 81% non-UAE Arabs (n = 106), 13% Asians (n = 17) and 6% Emiratis (n = 8)) with valid ATLS-2 data without missing scores and Fibion data of minimum 10 h/day for at least 3 weekdays and 1 weekend day were analyzed. Concurrent validity between the two methods was assessed by the Spearman rho correlation and Bland-Altman plots. RESULTS: The questionnaire underestimated sedentary and physical activity time compared to the accelerometer data. Only negligible to weak correlations (r ≤ 0.12; p > 0.05) were found for sitting, walking, cycling, moderate intensity activity, high intensity activity and total activity time. In addition, a proportional/systematic bias was evident in the plots for all but two (walking and moderate intensity activity time) of the outcome measures of interest. CONCLUSIONS: Overall, self-reported ATLS-2 sedentary and physical activity time had low correlation and agreement with objective Fibion accelerometer measurements in adolescents and young adults in the UAE. Therefore, sedentary and physical activity assessment for these groups should not be limited to self-reported measures.


Subject(s)
Arabs , Sedentary Behavior , Humans , Adolescent , Young Adult , Self Report , United Arab Emirates , Cross-Sectional Studies , Accelerometry/methods , Exercise , Surveys and Questionnaires , Life Style , Reproducibility of Results
3.
Membranes (Basel) ; 13(3)2023 Mar 20.
Article in English | MEDLINE | ID: mdl-36984745

ABSTRACT

This paper concerns the development and analysis of multigeneration systems based on hybrid sources such as biomass and wind. Industry requires different types of sources to provide several outputs, so the goal of this research was to fulfill the industrial requirement with optimization. The multigeneration cycle supplies enough power to satiate energy demands, i.e., power, cooling, hydrogen, air conditioning, freshwater, hot water, and heating. For this, the multigeneration cycle was modeled in the Engineering Equation Solver (EES) and Simulink to obtain optimized results for the industry. Energy and exergy for the multigeneration cycle were determined to assess the performance of the cycle and to investigate the optimized results for the overall system. This study shows that for configuration selection and design, different thermodynamic, economic, and environmental aspects should be considered. Based on the results, the selection of the best location for this multigeneration system was made. Power output from the wind turbine was around 7 MW and from biogas 0.6 MW. The overall exergy efficiency of the multigeneration system was found to be 0.1401.

4.
Adv Biomed Res ; 12: 250, 2023.
Article in English | MEDLINE | ID: mdl-38192888

ABSTRACT

Background: Piwi-like RNA-mediated gene silencing 2 (PIWIL2) is a member of AGO/PIWI gene family, which is enriched in cancer stem cells (CSCs). The purpose of this research was to investigate the overexpression of PIWIL2 and its role in the induction of EMT and CSC properties in MCF7 breast cancer cell line. Materials and Methods: MCF7 cells were transfected with the human gene PIWIL2 (Hili) under the control of CMV promoter utilizing the neon electroporation method. Subsequently, the selection was conducted using G418, and doubling time was calculated in the transformed and control cells. RT and real-time PCR were also performed to analyze the expression of epithelial and mesenchymal genes and those related to CSCs. Results: According to the observations from this study, transfecting MCF7 cells with PIWIL2 triggered the conversion of epithelial cells to mesenchymal cells and induced the genes specific for breast CSCs, which was coincident with 9-h reduction in the doubling time of the transfected cells. Furthermore, the molecular analyses revealed a significant reduction in the expression of epithelial markers, while a significant increase was detected in the expression of mesenchymal genes and many CSC biomarkers. Conclusion: PIWIL2 protein acts as a master regulatory protein that is able to manipulate the transcription through specific signaling pathways, which allow the cells to gain stem cell-like properties.

5.
J Infect Dev Ctries ; 16(6): 1081-1088, 2022 06 30.
Article in English | MEDLINE | ID: mdl-35797304

ABSTRACT

INTRODUCTION: Although vaccines are the safest and most effective means to prevent and control infectious diseases, the increasing rate of vaccine hesitancy and refusal (VHR) has become a worldwide concern. We aimed to find opinions of parents on vaccinating their children and contribute to available literature in order to support the fight against vaccine refusal by investigating the reasons for VHR on a global scale. METHODOLOGY: In this international cross-sectional multicenter study conducted by the Infectious Diseases International Research Initiative (ID-IRI), a questionnaire consisting of 20 questions was used to determine parents' attitudes towards vaccination of their children. RESULTS: Four thousand and twenty-nine (4,029) parents were included in the study and 2,863 (78.1%) were females. The overall VHR rate of the parents was found to be 13.7%. Nineteen-point three percent (19.3%) of the parents did not fully comply with the vaccination programs. The VHR rate was higher in high-income (HI) countries. Our study has shown that parents with disabled children and immunocompromised children, with low education levels, and those who use social media networks as sources of information for childhood immunizations had higher VHR rates (p < 0.05 for all). CONCLUSIONS: Seemingly all factors leading to VHR are related to training of the community and the sources of training. Thus, it is necessary to develop strategies at a global level and provide reliable knowledge to combat VHR.


Subject(s)
Communicable Diseases , Vaccination Hesitancy , Child , Cross-Sectional Studies , Female , Health Knowledge, Attitudes, Practice , Humans , Male , Parents , Patient Acceptance of Health Care , Surveys and Questionnaires , Vaccination
6.
Chem Pharm Bull (Tokyo) ; 64(3): 263-71, 2016.
Article in English | MEDLINE | ID: mdl-26699093

ABSTRACT

Benzoxazinones and quinazolinones have a wide spectrum of biological activity. In this paper we focused on studying the antimicrobial and anti-inflammatory activities of some newly synthesized benzoxazinone and quinazolinone derivatives. Thus we prepared 2-[α-benzoylaminostyryl]-6,8-dibromo-3,1-benzoxazin-4(H)-one 2 which underwent a reaction with primary and secondary amines, and hydrazine hydrate to give compounds 3, 4 and 5, respectively. Treatment of 2 with hydroxylamine hydrochloride, formamide and/or NaN3/AcOH afforded compounds 7, 8, 11 and 12, respectively. Also, compound 2 reacted with maleic anhydride, aromatic hydrocarbons and/or active methylene compounds to produce compounds 13, 15a-c and 16, respectively. Most of the newly synthesized compounds showed significant antimicrobial and anti-inflammatory activities comparable to ampicillin, mycostatine and indomethacin positive controls.


Subject(s)
Benzoxazines/chemical synthesis , Benzoxazines/pharmacology , Quinazolinones/chemical synthesis , Quinazolinones/pharmacology , Anti-Infective Agents/chemical synthesis , Anti-Infective Agents/pharmacology , Anti-Inflammatory Agents/chemical synthesis , Anti-Inflammatory Agents/pharmacology , Magnetic Resonance Spectroscopy , Mass Spectrometry
7.
Molecules ; 18(1): 832-44, 2013 Jan 11.
Article in English | MEDLINE | ID: mdl-23344196

ABSTRACT

Aiming for the synthesis of new heterocyclic compounds containing a sulfonamido moiety suitable for use as antibacterial agents, the precursor ethyl {[4-N-(4,6-dimethylpyrimidin-2-yl)sulfamoyl]phenylazo}cyanoacetate was reacted with a variety of active methylene compounds producing pyran, pyridine and pyridazine derivatives. Also, the reactivity of the precursor hydrazone towards hydrazine derivatives to give pyrazole and oxazole derivatives was studied. On the other hand, treatment of the same precursor with urea, thiourea and/or guanidine hydrochloride furnished pyrimidine and thiazine derivatives, respectively. The newly synthesized compounds were tested for antibacterial activity, whereby eight compounds were found to have high activities.


Subject(s)
Anti-Bacterial Agents/chemical synthesis , Pyrazoles/chemical synthesis , Pyridazines/chemical synthesis , Pyrimidines/chemical synthesis , Sulfonamides/chemical synthesis , Anti-Bacterial Agents/pharmacology , Bacillus cereus/drug effects , Cyclization , Disk Diffusion Antimicrobial Tests , Nitriles , Oxazoles/chemical synthesis , Oxazoles/pharmacology , Proteus mirabilis/drug effects , Pyrazoles/pharmacology , Pyridazines/pharmacology , Pyrimidines/pharmacology , Serratia marcescens/drug effects , Staphylococcus aureus/drug effects , Sulfonamides/pharmacology
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