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排序方式: 共有8040条查询结果,搜索用时 15 毫秒
1.
Muhammad I. Zafar Jiequn Han Xu-Hui Zhou & Heng Xiao 《Communications In Computational Physics》2022,32(2):336-363
Partial differential equations (PDEs) play a dominant role in the mathematical modeling of many complex dynamical processes. Solving these PDEs often requires
prohibitively high computational costs, especially when multiple evaluations must be
made for different parameters or conditions. After training, neural operators can provide PDEs solutions significantly faster than traditional PDE solvers. In this work,
invariance properties and computational complexity of two neural operators are examined for transport PDE of a scalar quantity. Neural operator based on graph kernel network (GKN) operates on graph-structured data to incorporate nonlocal dependencies.
Here we propose a modified formulation of GKN to achieve frame invariance. Vector
cloud neural network (VCNN) is an alternate neural operator with embedded frame
invariance which operates on point cloud data. GKN-based neural operator demonstrates slightly better predictive performance compared to VCNN. However, GKN requires an excessively high computational cost that increases quadratically with the
increasing number of discretized objects as compared to a linear increase for VCNN. 相似文献
2.
Raya Saab MD Anas Obeid MD Fatiha Gachi MD Houda Boudiaf MD Lilit Sargsyan MD Khulood Al-Saad MD Tamar Javakhadze MD Azim Mehrvar MD Sawsan Sati Abbas MD Yasir Saadoon Abed Al-Agele MD Salma Al-Haddad MD Mouroge Hashim Al Ani MD Suleiman Al-Sweedan MD Amani Al Kofide MD Wasil Jastaniah MD Nisreen Khalifa MD Elie Bechara MD Malek Baassiri MD Peter Noun MD Jamila El-Houdzi MD Mohammed Khattab MD Krishna Sagar Sharma MD Yasser Wali MD Naureen Mushtaq MD Aliya Batool MD Mahwish Faizan MD Muhammad Rafie Raza MD Mohammad Najajreh MD Mohammed Awad Mohammed Abdallah MD Ghada Sousan MD Khaled M. Ghanem MD Ulker Kocak MD Tezer Kutluk MD Hacı Ahmet Demir MD Hamoud Hodeish MD Samar Muwakkit MD Asim Belgaumi MD Abdul-Hakim Al-Rawas MD Sima Jeha MD 《Cancer》2020,126(18):4235-4245
3.
Expression of Salivary S100A7 Levels in Stage I Oral Submucous Fibrosis: A Clinical and Laboratory Study 下载免费PDF全文
Muhammad Arsalan RaffatNaila Irum HadiOsama AlghamdiKhulud Abdulrahman Al-AaliModhi Al DeebTariq AbduljabbarFahim Vohra 《Asian Pacific journal of cancer prevention》2020,21(4):1115-1119
Background: Oral submucous fibrosis (OSF) is a chronic debilitating condition characterized by juxta-epithelial fibrosis. The main etiological agent associated with the high-risk precancerous condition is areca nut use. S100A7 is a member of the largest calcium-binding proteins exclusively found in vertebrates and are associated with the regulation of numerous intracellular and extracellular functions. The aim of this study was to investigate the expression of protein S100A7 in salivary samples of individuals with stage I OSF and healthy controls. Methods: This study included 63 participants, 30 of whom had OSF stage I and 33 healthy controls. Nonprobability quota sampling technique was utilized for recruitment of the study participants. A structured baseline questionnaire was used to collect demographic data. Saliva samples were collected by passive droll technique in a sterile container. Salivary levels of S100A7 were quantified by enzyme-linked immunosorbent assay. For the normality of the data Shapiro Wilk test was performed. Student t-test was commuted to evaluate the expression of S100A7 protein expression between both the study groups. Results: The mean salivary S100A7 value for stage I OSF group was 0.334 ng/ml, compared to 0.172 ng/ml for healthy controls. Student t-test reported a statistically significant difference, indicating higher levels of S100A7 in stage I OSF group than in healthy controls (p < 0.001). In the individual group analysis, a significant negative correlation was found between salivary S100A7 and duration of areca nut use (r = –0.45, p = 0.009) and gutka chewing (r = –0.20, p = 0.03), while a significant positive correlation was found between salivary S100A7 and mouth opening (r = 0.03, p = 0.04). Conclusions: Higher levels of S100A7 protein level was seen in stage I OSF group in comparison to the healthy individuals. Results of our study suggest that S100A7 could be used as a surrogate assessment to identify patients at risk of OSF development. 相似文献
4.
Dengue, a mosquito‐borne viral disease, causes about 100 million cases of infection annually. It is a major public concern, and if left untreated or improperly diagnosed, may cause serious health problems or even death. Historically, dengue has not considered priorities for pharmaceutical companies made the available treatment options. Therefore, medicinal scientists are revealing new insights and enabling novel interventions and approaches to dengue prevention and control. Diterpenes, a class of terpenes have gained much attention due to their diverse biological effects. This review aimed at summarizing available evidences of diterpenes and their derivatives acting against dengue virus and their vectors. For this, an updated search was made in the databases: PubMed and ScienceDirect by using specific keywords. Among the 117 published reports, a total of 30 articles was included in this review. Findings suggest that a number of diterpenes and/or their derivatives act against dengue virus and their two potential vectors namely Aedes aegypti and Ae. albopictus. In conclusion, diterpenes and their derivatives may have the potential alternative therapeutic tools for the management of dengue virus and some associated diseases transmitted by Aedes mosquito. 相似文献
5.
6.
Inna Y. Gong Nigel S. Tan Sammy H. Ali Gerald Lebovic Muhammad Mamdani Shaun G. Goodman Dennis T. Ko Andreas Laupacis Andrew T. Yan 《The Canadian journal of cardiology》2019,35(5):653-660
Background
Although it is known that women do not participate in trials as frequently as men, there are limited recent data examining how women recruitment has changed over time.Methods
We conducted MEDLINE search using a validated strategy for randomized trials published in New England Journal of Medicine, Lancet, and Journal of the American Medical Association between 1986 and 2015, and included trials evaluating pharmacologic or nonpharmacologic therapies. We abstracted data on demographics, intervention type, clinical indication, and trial design characteristics, and examined their relationships with women enrollment.Results
In total, 598 trials met inclusion criteria. Women enrollment increased significantly over time (21% between 1986 and 1990 to 33% between 2011 and 2015; Pfor trend < 0.001) and did not differ by journal or funding source. Women enrollment varied with clinical indication, comprising 37% for non–coronary artery disease vascular trials, 30% for coronary artery disease trials, 28% for heart failure trials, and 28% for arrhythmia trials (P < 0.001), which were all significantly lower than the expected proportion in disease populations (P < 0.001). Women enrollment varied with trial type (31%, 29%, and 26% for pharmacologic, device, and procedural trials, respectively; P = 0.001). These findings were corroborated using multivariable analysis. We found significant positive correlations between women enrolled, and mean age and total number of participants. Fewer women were enrolled in trials reporting statistically significant results than those who did not (P = 0.001).Conclusions
Although enrollment of women has increased over time, it remains lower than the relative proportion in the disease population. Future studies should elucidate the reasons for persistent under-representation of women in clinical trials. 相似文献7.
El-Khalik Sarah Ragab Abd Ibrahim Rowida Raafat Ghafar Muhammad Tarek Abdel Shatat Doaa El-Deeb Omnia Safwat 《Journal of assisted reproduction and genetics》2022,39(5):1115-1124
Journal of Assisted Reproduction and Genetics - Ferroptosis is associated with oxidative stress (OS) and is caused by iron-dependent lipid-peroxidative damage, but its role in PE is unclear. The... 相似文献
8.
9.
Faisal Kamal Muhammad Ali Khan Sachit Sharma Zaid Imam Colin W. Howden 《Gastroenterology》2021,160(7):2588-2590.e7
10.