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991.
Equilibrium molecular dynamics simulation has been carried out for the thermal transport characterization of nanometer sized carbon and silicon doped stanene nanoribbon (STNR). The thermal conduction properties of doped stanene nanostructures are yet to be explored and hence in this study, we have investigated the impact of carbon and silicon doping concentrations as well as doping patterns namely single doping, double doping and edge doping on the thermal conductivity of nanometer sized zigzag STNR. The room temperature thermal conductivities of 15 nm × 4 nm doped zigzag STNR at 2% carbon and silicon doping concentration are computed to be 9.31 ± 0.33 W m−1 K−1 and 7.57 ± 0.48 W m−1 K−1, respectively whereas the thermal conductivity for the pristine STNR of the same dimension is calculated as 1.204 ± 0.21 W m−1 K−1. We find that the thermal conductivity of both carbon and silicon doped STNR increases with the increasing doping concentration for both carbon and silicon doping. The magnitude of increase in STNR thermal conductivity due to carbon doping has been found to be greater than that of silicon doping. Different doping patterns manifest different degrees of change in doped STNR thermal conductivity. Double doping pattern for both carbon and silicon doping induces the largest extent of enhancement in doped STNR thermal conductivity followed by single doping pattern and edge doping pattern respectively. The temperature and width dependence of doped STNR thermal conductivity has also been studied. For a particular doping concentration, the thermal conductivity of both carbon and silicon doped STNR shows a monotonic decaying trend at elevated temperatures while an opposite pattern is observed for width variation i.e. thermal conductivity increases with the increase in ribbon width. Such comprehensive study on doped stanene would encourage further investigation on the proper optimization of thermal transport characteristics of stanene nanostructures and provide deep insight in realizing the potential application of doped STNR in thermoelectric as well as thermal management of stanene based nanoelectronic devices.Tunable thermal transport of doped stanene nanoribbon considering the impact of doping concentration, doping pattern, temperature and nanoribbon width. 相似文献
992.
Osama Hamid Ahmed Eltelbany Abdul Mohammed Khaled Alsabbagh Alchirazi Sushrut Trakroo Imad Asaad 《Annals of hepatology》2022,27(5):100727
Introduction and objectivesNon-alcoholic steatohepatitis (NASH) is a severe form of non-alcoholic fatty liver disease (NAFLD) that can progress to liver cirrhosis, liver failure and hepatocellular carcinoma. It is the second leading cause of liver transplant in the US. We aim to investigate the prevalence, demographics and risk factors NASH patients in the US.Patients and methodsWe used a large database (Explorys IBM) that aggregates electronic health records from 26 nationwide healthcare systems. We identified adults with NASH between 2010-2020. Demographics including age, gender and race were collected. NASH risk factors including Diabetes Millets (DM), Hyperlipidemia (HLD), Hypertension (HTN) and Obesity were also collected. Cochran-Armitage test was used to assess the statistical significance of year-by-year trend. Univariable and multivariable logistic regression were used to estimate the odds ratio (OR) of risk factors.ResultsNASH annual prevalence rate increased from 1.51% in 2010 to 2.79% in 2020 (p < 0.0001). The proportion of patients with NASH by gender was 54.1% female vs 45.9% male (OR 1.04 [0.91-1.11]). Caucasian had higher odds of NASH than non-Caucasian (OR 1.42 [1.31-1.54]). NASH is strongly associated with DM and obesity (OR 18.61 [17.35-19.94]) and (OR 20.97 [17.87-23.21]), respectively. Other components of metabolic syndrome were associated with NASH to a lesser degree; HTN (OR 3.24 [3.20-3.28]) and HLD (OR 4.93 [4.85-4.01]).ConclusionThe prevalence of NASH has significantly increased in the US in the last decade. This is likely related to the increased prevalence of risk factors as well as increased awareness of the disease. 相似文献
993.
Emad Elshebini Hozaifa Elsawah Taghreed Fathy Sherry Abdelrahman Omar Youssif Soaad Ashraf Nibal Mourad Mohamed Elnaggar Ahmed Elshebiny Shymaa Daif Enas Zahran 《The Egyptian Rheumatologist》2021,43(2):167-171
BackgroundInflammatory diseases can interfere with adequate nutrition and even lead to a malnourished state. Nutritional deficiency manifestations may be similar to rheumatologic manifestations.Aim of the workTo assess whether malnutrition is an associated feature of rheumatic diseases (RDs).Patients and methodsA multicenter study included Egyptian patients with different RDs; nutrition measurements and common features of deficiency were assessed; general appearance, skin, hair/nail changes, spooning of nails, night blindness, mouth problems, edema, tetany, dysphagia, diarrhea, thyromegaly, loss of appetite and weight loss.ResultsThe study included 284 patients with various RDs: rheumatoid arthritis (RA) (n = 128), systemic lupus erythematosus (n = 120), Behçet’s disease (n = 17), spondyloarthritis (n = 6), systemic sclerosis (n = 5), dermatomyositis (n = 2), relapsing polychondritis (n = 2), and one patient each with familial Mediterranean fever, Gout, Still's disease and undifferentiated connective tissue disease. Muscle wasting was present in 44(15.5%) patients, spooning of nails in 26(9.2%), night blindness in 38(13.4%), glossitis in 48(16.9%), tetany in 32(11.3%) and loss of appetite in 51(18%). Although there was significant differences among RDs in some nutritional deficiency signs, the type and their durations did not significantly affect symptoms or signs of nutritional deficiency, while age was associated with peripheral edema (p = 0.014) and tetany (p = 0.009); azathioprine was associated with hair/nail changes (p = 0.04); methotrexate with peripheral edema and hair/nail changes (p = 0.002, p = 0.01 respectively); and hydroxychloroquine was negatively associated with skin rash, wasting and hair/nail changes (p = 0.011, p = 0.001 and p < 0.0001 respectively).ConclusionNutritional deficiency is common among RD patients especially elderly and should be monitored frequently regardless type and onset. 相似文献
994.
995.
Proietti Riccardo Dowd Rory Gee Lim Ven Yusuf Shamil Panikker Sandeep Hayat Sajad Osman Faizel Patel Kiran Salim Handi Aldhoon Bashar Foster Will Merghani Ahmed Kuehl Michael Banerjee Prithwish Lellouche Nicolas Dhanjal Tarvinder 《Journal of interventional cardiac electrophysiology》2021,62(3):519-529
Journal of Interventional Cardiac Electrophysiology - Substrate mapping has highlighted the importance of targeting diastolic conduction channels and late potentials during ventricular tachycardia... 相似文献
996.
997.
998.
Esmael Ahmed Abdelsalam Mohamed Shoukri Amr Elsherif Mohammed 《Sleep & breathing》2021,25(4):2119-2126
Sleep and Breathing - Migraines are associated with multiple comorbidities like depression, anxiety, poor sleep quality, and subjective cognitive impairment (SCI). This study aimed to evaluate the... 相似文献
999.
Role of endoscopic ultrasound and cyst fluid tumor markers in diagnosis of pancreatic cystic lesions
Hussein Hassan Okasha Abeer Abdellatef Shaimaa Elkholy Mohamad-Sherif Mogawer Ayman Yosry Magdy Elserafy Eman Medhat Hanaa Khalaf Magdy Fouad Tamer Elbaz Ahmed Ramadan Mervat E Behiry Kerolis Y William Ghada Habib Mona Kaddah Haitham Abdel-Hamid Amr Abou-Elmagd Ahmed Galal Wael A Abbas Ahmed Youssef Altonbary Mahmoud El-Ansary Aml E Abdou Hani Haggag Tarek Ali Abdellah Mohamed A Elfeki Heba Ahmed Faheem Hani M Khattab Mervat El-Ansary Safia Beshir Mohamed El-Nady 《World journal of gastrointestinal endoscopy》2022,14(6):402-415