We consider three different methods for the coupling of the finite element method and the boundary element method, the Bielak–MacCamy coupling, the symmetric coupling, and the Johnson–Nédélec ...coupling. For each coupling, we provide discrete interior regularity estimates. As a consequence, we are able to prove the existence of exponentially convergent
H
-matrix approximants to the inverse matrices corresponding to the lowest order Galerkin discretizations of the couplings.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The inverse of the stiffness matrix of the time-harmonic Maxwell equation with perfectly conducting boundary conditions is approximated in the blockwise low-rank format of
H
-matrices. Under a ...technical assumption on the mesh, we prove that root exponential convergence in the block rank can be achieved, if the block structure conforms to a standard admissibility criterion.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Silicon nanowire field-effect transistors are promising devices used to detect minute amounts of different biological species. We introduce the theoretical and computational aspects of forward and ...backward modeling of biosensitive sensors. Firstly, we introduce a forward system of partial differential equations to model the electrical behavior, and secondly, a backward Bayesian Markov-chain Monte-Carlo method is used to identify the unknown parameters such as the concentration of target molecules. Furthermore, we introduce a machine learning algorithm according to multilayer feed-forward neural networks. The trained model makes it possible to predict the sensor behavior based on the given parameters.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Coronavirus disease 2019 or COVID-19 has rapidly emerged as a global pandemic. This viral infection involves the upper respiratory tract and could lead to severe pneumonia with respiratory distress ...or even death. Certain studies have found higher initial plasma levels of most pro-inflammatory cytokines during the course of the infection. In this context, both
and
studies have revealed that metronidazole could decrease the levels of several cytokines, which are known to increase during the COVID-19 infection, including interleukin (IL)8, IL6, IL1B, tumor necrosis factor (TNF)α, IL12, IL1α, and interferon (IFN)γ, as well as the levels of C-reactive protein (CRP) and neutrophil count. Furthermore, the drug could decrease neutrophil-generated reactive oxygen species during inflammation. Metronidazole could counteract majority of the immunopathological manifestations of the COVID-19 infection. Therefore, studies with a large sample size are required to determine the efficacy of metronidazole in the treatment of COVID-19 infection.
Oxidative stress due to iron accumulation in patients with beta-thalassemia major (BTM) causes complications such as tissue damage and destruction. This study aimed to assess the association between ...the serum prooxidant/antioxidant balance (PAB) and blood parameters in patients with BTM.
This cross-sectional study included 92 patients with BTM. In this study, PAB was measured using an enzyme-linked immunosorbent assay (ELISA). Serum ferritin, blood urea nitrogen (BUN), creatinine (Cr), alanine aminotransferase (ALT), aspartate aminotransferase (AST), thyroid-stimulating hormone (TSH), total cholesterol (TC), triglyceride (TG), complete blood cell count (CBC), and history of blood transfusion were recorded. The association of the blood parameters was assessed across the tertiles (T) of serum PAB (highest T vs. lowest T).
The results showed that high serum ferritin was directly associated with serum PAB odds ratio (OR), 12.80; 95% confidence interval (CI), 2.98‒54.91; T3 vs. T1. Also, direct associations were found for high TC (OR, 4.97; 95% CI, 1.42‒17.32; T3 vs. T1), high ALT (OR, 4.95; 95% CI, 1.33‒18.46; T3 vs. T1) and high TSH (OR, 3.78; 95% CI, 1.10‒13.02; T3 vs. T1).
The findings of the present study showed that serum PAB levels were directly associated with ferritin, ALT, TC, and TSH levels. This indicates that improvements in blood parameters, especially ferritin and TSH levels, occur by ameliorating oxidative stress in patients with BTM.
A recently developed application of computer vision is pathfinding in self-driving cars. Semantic scene understanding and semantic segmentation, as subfields of computer vision, are widely used in ...autonomous driving. Semantic segmentation for pathfinding uses deep learning methods and various large sample datasets to train a proper model. Due to the importance of this task, accurate and robust models should be trained to perform properly in different lighting and weather conditions and in the presence of noisy input data. In this paper, we propose a novel learning method for semantic segmentation called layer-wise training and evaluate it on a light efficient structure called an efficient neural network (ENet). The results of the proposed learning method are compared with the classic learning approaches, including mIoU performance, network robustness to noise, and the possibility of reducing the size of the structure on two RGB image datasets on the road (CamVid) and off-road (Freiburg Forest) paths. Using this method partially eliminates the need for Transfer Learning. It also improves network performance when input is noisy.
Key Clinical Message
A patient presented with edema, ascites and jaundice. Histologic report was consistent with Celiac Disease. Liver biopsy commensurate with Glycogen storage disease III, which was ...confirmed by genetic testing. A gluten‐free diet was initiated. After 2 months, ascites was relieved, hepatic function was improved, and hepatic size reduced.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
We present an adaptive multilevel Monte Carlo algorithm for solving the stochastic drift–diffusion–Poisson system with non-zero recombination rate. The a-posteriori error is estimated to enable ...goal-oriented adaptive mesh refinement for the spatial dimensions, while the a-priori error is estimated to guarantee linear convergence of the H1 error. In the adaptive mesh refinement, efficient estimation of the error indicator gives rise to better error control. For the stochastic dimensions, we use the multilevel Monte Carlo method to solve this system of stochastic partial differential equations. Finally, the advantage of the technique developed here compared to uniform mesh refinement is discussed using a realistic numerical example.
•The a-priori error estimation for the space-discretized system is provided.•For the coupled system of equations, an accurate error estimator is computed.•The MLMC method is coupled with the adaptive refinement to solve a system of nonlinear stochastic equations.•The developed method is used for a realistic model, i.e. the RDF effect in DG-MOSFETs.•The new technique reduces the CPU time and computational costs significantly.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Background: We aimed to elucidate the pathogenic bacterial and fungal profiles of specimens obtained from suspected ocular infections at Farabi Eye Tertiary Referral Hospital, Tehran, Iran.Methods: ...In this cross-sectional study, we collected data from ocular specimens taken during the seven-year period of 2011 to 2018, and the results were then retrospectively analyzed. Samples had been obtained from patients who were investigated for ocular infections.Results: Overall, 16,656 ocular samples were evaluated. The mean patient age was 48.31 ± 26.62 years. Most patients were men (60.33%), and men in the 7th decade of life were the largest represented group. The seasonal distributions of specimen collection sites followed the overall distribution of collection sites by year. Specimens obtained from the cornea were the most common (49.24%), also representing the largest number of specimens in all seasons. The most commonly isolated fungal microorganisms were Fusariumspp., followed by Aspergillusspp. and Candida albicans. Of the 6,556 specimens with positive bacterial cultures, 59% produced gram-positive bacteria, while the remainder produced gram-negative pathogens. The most commonly isolated bacteria were Pseudomonas aeruginosa(17.77%), Staphylococcus epidermidis (13.80%), Streptococcus pneumoniae(13.27%), S. viridans(12.23%), and S. aureus(11.18%).Conclusion: Most submitted specimens were obtained from the cornea. The most commonly isolated fungal microorganisms were Fusariumspp., followed by Aspergillusspp. and C. albicans. The most commonly isolated bacteria were P. aeruginosa, followed by S. epidermidis and S. pneumoniae.
Association of Selenium (Se) deficiency, an essential trace element, has been found with human diseases. Identifying literature trends on the effects of Se on the thyroid may guide in planning future ...studies.
A literature search was conducted using the Web of Science database to identify studies on Se and the thyroid published over the 20 years duration (1995-Dec 2014). Scientometric indices were used to draw field maps. The scientific processes, structure, evidence history, and international collaborations were included in the map. The most influential authors, journals, institutions, and countries were also examined.
Our search identified 184 research and review papers. The number of scientific studies on Se and the thyroid has been irregular, but interest in this topic has increased in recent years. The highest number of studies was published in 2014 (16 papers) and overall growth factor of publication was 3.78. Overall, 744 authors from 282 institutions in 43 countries published in this field. The author J. Kohrle (828 citations, 14 publications), and German scientists (1272 citations, 30 publications) were most influential.
This study reveals the interrelationships between different publications on the effects of Se on the thyroid. Leading scientific issues and their extent of impact were successfully determined by examining citations. The results of systematic citations and mapping fields can be used to assist in policy and management contexts.
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