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The aim of this study was to evaluate the patency of the proximal and distal radial artery after coronary procedures performed via the distal radial artery (DRA). Ultrasound (US) as the most reliable method was used to diagnose radial artery occlusions (RAO). We evaluated 115 patients who underwent catheterization via distal radial access (dTRA). Following the procedure and after successful hemostasis (80 ± 36 min), arterial patency and diameter at conventional transradial access (cTRA) and distal puncture sites (either in the anatomical snuffbox or the dorsal distal RA) were assessed. No RAO were found in the proximal or distal RA and there were no significant other complications. The mean diameter of the radial artery at conventional puncture site was 2.86 ± 0.49 mm and at distal puncture site 2.31 ± 0.47 mm (p 0.001). Postprocedural compression time of dTRA was very short. In conclusion distal radial access was associated with the absence of early arterial occlusion, significant local bleeding and other relevant complications.

This paper deals with wildfire identification in the Alaska regions as a semantic segmentation task using support vector machine classifiers. Instead of colour information represented by means of BGR channels, we proceed with a normalized reflectance over 152 days so that such time series is assigned to each pixel. We compare models associated with $\mathcal{l}1$-loss and $\mathcal{l}2$-loss functions and stopping criteria based on a projected gradient and duality gap in the presented benchmarks.

Gagea bohemicas. lat. is morphologically and karyologically highly variable group with many morphologically similar “narrow” taxa currently considered as a single variable species. It is predominantly distributed in Mediterranean and warmer parts of temperate belt of Europe. The large-scale data on its cytogeography and population cytotype structure which could provide a basis for taxonomy is lacking, only scattered data on ploidy have been published from various parts of its range. In this study, we sampled 106 populations in broader Central Europe, the northeastern Balkan Peninsula and the northwestern Black Sea coast in order to analyse their ploidy level, genome size and pollen stainability. Two cytotypes, i.e., tetraploid (2n = 48) and pentaploid (2n = 60), were found in the study area using chromosome counting and flow cytometry, both in pure and mixed-ploidy populations. Pure pentaploid populations are mainly distributed in Austria, Czechia, northwestern Hungary and Slovakia while tetraploid cytotype in pure and mixed-ploidy populations forming two lineages which are concentrated into two disjunct geographical areas: western in Germany and Switzerland, and eastern in Bulgaria, southeastern Hungary, northern Greece, Romania, Serbia and Ukraine. The two lineages differ in their genome size regardless of their ploidy, indicating their independent origin. Analysis of pollen stainability using a modified Alexander stain revealed an unusual pattern with tetraploids having a lower pollen stainability (mean 44.29 %) than pentaploids (mean 70.70 %) but the western and eastern populations differed again from each other.

A new natural hybrid Saxifraga ×klimesii Hajman, Horák & Hroneš from Ladakh (NW India) is described and illustrated. This hybrid resulted from cross between Saxifraga meeboldii Engler & Irmscher and Saxifraga pulvinaria Harry Smith. The morphology of the hybrid plants and its parental taxa was evaluated using morphometric analysis of both living plants and herbarium specimens. An artificial cross was also made to compare its morphology with spontaneous hybrids. Ploidy level and relative genome size was established using flow cytometry. Saxifraga ×klimesii is intermediate in morphology and relative genome size between both parents. It differs from S. meeboldii by shorter and wider rosette leaves and lighter yellow, larger and wider petals and from S. pulvinaria by larger rosettes, often more than one pore on leaves and usually yellow coloured petals. A lectotype is selected for S. pulvinaria.

Uvod: Extrakorporalni membranova oxygenace (ECMO) je metoda mimotělniho oběhu se vzrůstajicim užitim u kardiogenniho soku nebo refrakternich srdecnich zastav. Pece o tyto pacienty je vesměs vazana na centra s kardiochirurgii. Technický vývoj usnadil zavedeni okruhu bez chirurgicke asistence a pro management oběhove podpory neni nutna přitomnost perfuzionisty.

This paper presents on four chosen benchmarks an experimental evidence of efficiency of active-set-based algorithms and a gradient projection scheme exploiting Barzilai–Borwein-based steplength rule for box-constrained quadratic programming problems, which have theoretically proven rate of convergence. The crucial phase of active-set-based algorithms is the identification of the appropriate active set combining three types of steps—a classical minimization step, a step expanding the active set and a step reducing it. Presented algorithms employ various strategies using the components of the gradient for an update of this active set to be fast, reliable and avoiding undesirable oscillations of active set size.

Toto odborne stanovisko reprezentuje nazor výse uvedených odborných spolecnosti a bylo vytvořene v souladu s vědeckými a lekařskými poznatky dostupnými v době připravy publikace. Cilem tohoto dokumentu je pomahat lekařům při volbě nejlepsiho diagnostickeho a lecebneho postupu pro každeho pacienta s daným onemocněnim, přicemž je posuzovan jak vliv na klinicke výsledky, tak poměr přinosu a rizika daneho postupu. Definitivni rozhodnuti týkajici se konkretniho pacienta vsak musi ucinit osetřujici lekař po konzultaci s pacientem a tento dokument v žadnem připadě nenahrazuje individualni odpovědnost každeho lekaře. Obsah tohoto dokumentu byl publikovan pouze pro nekomercni a edukacni ucely.

The paper is motivated by a strong interest in numerical analysis of flow in fractured porous media, e.g., rocks in geo-engineering applications. It follows the conception of porous media as a continuum with fractures which are represented as lower dimensional objects. In the paper, the finite element discretization of the flow in coupled continuum and fractures is used; fluid pressures serve as the basic unknowns. In many applications, the flow is connected with deformations of the porous matrix; therefore, the hydro-mechanical coupling is also considered. The fluid pressure is transferred to the mechanical load in both pores and fractures and the considered mechanical model involves elastic deformations of the porous matrix and opening/closing of the fractures with the non-penetration constraint. The mechanical model with this constraint is implemented via the technique of the Lagrange multipliers, duality formulation, and combination with a suitable domain decomposition method. There is usually lack of information about problem parameters and they undergo many uncertainties coming e.g. from the heterogeneity of rock formations and complicated realization of experiments for parameter identification. These experiments rarely provide some of the asked parameters directly but require solving inverse problems. The stochastic (Bayesian) inversion is natural due to the mentioned uncertainties. In this paper, the implementation of the Bayesian inversion is realized via Metropolis-Hastings Markov chain Monte Carlo approach. For the reduction of computational demands, the sampling procedure uses the delayed acceptance of samples based on a surrogate model which is constructed during a preliminary sampling process. The developed hydro-mechanical model and the implemented Bayesian inversion are tested on two types of model inverse problems.

Currently, transradial access (TRA) is the recommended access for coronary procedures because of increased safety, with radial artery occlusion (RAO) being its most frequent complication, which will increasingly affect patients undergoing multiple procedures during their lifetimes. Recently, distal radial access (DRA) has emerged as a promising alternative access to minimize RAO risk. A large-scale, international, randomized trial comparing RAO with TRA and DRA is lacking.The aim of this study was to assess the superiority of DRA compared with conventional TRA with respect to forearm RAO.DISCO RADIAL (Distal vs Conventional Radial Access) was an international, multicenter, randomized controlled trial in which patients with indications for percutaneous coronary procedure using a 6-F Slender sheath were randomized to DRA or TRA with systematic implementation of best practices to reduce RAO. The primary endpoint was the incidence of forearm RAO assessed by vascular ultrasound at discharge. Secondary endpoints include crossover, hemostasis time, and access site-related complications.Overall, 657 patients underwent TRA, and 650 patients underwent DRA. Forearm RAO did not differ between groups (0.91% vs 0.31%; P = 0.29). Patent hemostasis was achieved in 94.4% of TRA patients. Crossover rates were higher with DRA (3.5% vs 7.4%; P = 0.002), and median hemostasis time was shorter (180 vs 153 minutes; P 0.001). Radial artery spasm occurred more with DRA (2.7% vs 5.4%; P = 0.015). Overall bleeding events and vascular complications did not differ between groups.With the implementation of a rigorous hemostasis protocol, DRA and TRA have equally low RAO rates. DRA is associated with a higher crossover rate but a shorter hemostasis time.

ný clanek představuje přistup Ceske asociace intervencni kardiologie k invazivni lecbě srdecnich onemocněni během koronavirove pandemie. Primarni angioplastika zůstava metodou volby pro lecbu pacientů s infarktem myokardu s elevacemi useku ST (STEMI) i pro nemocne s infarktem myokardu be elevaci useku ST (NSTEMI) a trvajici ischemii, bez ohledu na znalost přitomnosti koronaviru u těchto pacientů v době výkonu. Ostatni nemocni, kteři potřebuji katetrizacni lecbu srdecni nemoci, by měli být vysetřeni alespoň 48 hodin před přijetim do zdravotnickeho zařizeni na přitomnost COVID-19. Přiznivý průběh pandemie v Ceske republice umožňuje v soucasnosti katetrizacnim laboratořim postupný navrat k obvykle urovni kvality a dostupnosti invazivni lecby. © 2020, CKS.

Standardni radialni přistup z praveho ci leveho zapěsti se stal dominantni přistupovou cestou ke koronarnim katetrizacim a intervencim s doporucenim IA dle poslednich guidelines Evropske kardiologicke spolecnosti pro revaskularizaci myokardu z roku 2018. Od te doby bylo publikovano několik clanků o možnosti provadět intervencni výkony na koronarnich tepnach z tzv. distalniho radialniho přistupu. Tento clanek popisuje nase prvni zkusenosti s timto novým přistupem.

Bifurkacni leze tvoři 15-20 % vsech intervenovaných koronarnich lezi a jejich osetřovani je i přes výrazný pokrok v intervencni kardiologii i nadale spojeno s technickými obtižemi a horsi klinickou efektivitou. Zakladnim doporucovaným postupem pro osetřovani bifurkacnich lezi je "provisional stenting". Jako alternativni postup lze zvažit některou z dvoustentových technik. V nasem registru jsme se rozhodli posoudit bezpecnost, technickou a klinickou uspěsnost při použiti dedikovaneho bifurkacniho stentu Tryton Side Branch. Do registru bylo zařazeno 201 pacientů neselektovane populace osetřených v obdobi mezi cervnem 2012 a dubnem 2016 v Kardiovaskularnim centru Krajske nemocnice Liberec, u kterých bylo zvažovano užiti bifurkacniho stentu Tryton. Uspěsnost osetřeni bifurkacnich lezi při užiti stentu Tryton byla 85,07 %. Pacienty jsme pote sledovali v obdobi sesti měsiců od osetřeni. K infarktu myokardu doslo u tři pacientů, k revaskularizaci bylo nutno přistoupit pouze u tři pacientů, z toho vsak ani jednou nebylo potřeba osetřit cilovou tepnu nebo lezi. Otazka osetřovani bifurkacnich lezi zůstava do budoucna stale otevřena, jako možna alternativa se jevi užiti dedikovaných bifurkacnich stentů. Bifurkacni stent Tryton ma výhodu v ochraně bocni větve, jejiž osetřeni může být u větsiny standardnich technik problematicke. Stent Tryton lze dle nasich dat s výhodou použivat zejmena u bifurkacnich lezi s velkou bocni větvi (≥ 2,5 mm). Data z naseho registru tak svědci pro vysokou bezpecnost a uspěsnost osetřovani tohoto typu bifurkacnich lezi pomoci stentu Tryton. © 2019, CKS.

Kardiovaskularni choroby a mezi nimi ischemicka choroba srdecni patři na celni mista morbidity a mortality. Ve spolecnostech zapadniho typu je jistě prvotni přicinou postiženi věncitých tepen ateroskleroza. Neměli bychom ale zapominat na meně casta onemocněni, ktera věncite tepny mohou postihovat take. Jedna se o celou skalu různých onemocněni. Patři mezi ně vrozene anomalie věncitých tepen, spontanni disekce (casto spojene s fibromuskularni dysplazii), svalove můstky a různa systemova zanětliva onemocněni, ktera mohou různým způsobem postihovat věncite tepny. Diagnostika se opira předevsim o zobrazovaci metody. Lecba zavisi na danem onemocněni, a i když některe choroby mohou imitovat ateroskleroticke postiženi, výsledky běžných postupů mohou být meně uspokojive, nebo dokonce nevhodne.

This paper describes various methods for increasing the computational speed of an existing fatigue solver called PragTic. The paper describes the basic workflow of computational fatigue analysis, including multiaxial fatigue analysis as well. It documents some of the inefficiencies of the original PragTic version, and parallelization and scalability testing of the parallelized PragTic in three different case studies. These studies include a simple model example (hundreds of nodes) and a real world example (millions of nodes). The implemented parallelization techniques are tested using numerical experiments to demonstrate their parallel scalability. As an output of a unique analysis, the number of necessary and feasible evaluated planes in multiaxial analyses is monitored, and the outcome favoring integral methods for the multiaxial fatigue analysis is commented.

A significant part of Industry 4.0 is collecting data during manufacturing and optimizing production, and prolonging the machine lifetime. In our case, we propose to minimize the depth of cut on CNC to prolong cylinder lifetime in a rolling mill. Currently used measuring methods (precise template, clamp micrometer) without feedback are replaced with two 2-D micrometers. In our solution, we directly clamped the measuring head containing two micrometers on CNC's linear guidance. We propose a thin slice of metal (calibration template) with specific geometry designed for ongoing calibration in each cylinder's measuring cycle.The article's primary goal is to introduce a novel method of precisely processing data from both micrometers and one relative position (axis X, Z) given by CNCs linear guidance. Our team verified the Calibration Template's (CT) real profile on a Coordinate Measuring Machine (CMM).All horizontal sections of the CT are selected from measured data and fitted to the CT's corresponding section. All sections are replaced with landmarks to find the optimal transformation between both micrometer's spaces in the next step. Then we apply the found micrometer's geometry on raw data to compare the resulting CT's profile against the profile from CMM.

The contribution is motivated by the need for numerical analysis of flow in fractured porous media, i.e. rocks in the geo-engineering applications. We describe development and testing of numerical methods for simulation of (coupled) flow and deformation in a fractured porous environment. The hydraulic behavior is described by the Darcy flow in the porous matrix and the Poiseuille flow in the fractures. The fractures are considered as domains of reduced dimension. Both the matrix and fracture flow are interconnected by the flux through the fracture walls. The mechanical behavior is described by the linear elastic deformation of the porous matrix with contact conditions on fractures. In this way, it allows fracture opening and closing with the constraint on non-penetration. The slip effects are not considered. We consider both steady-state and time-dependent problems.

AIMS The Compare-Acute trial showed superiority of fractional flow reserve (FFR)-guided acute complete revascularisation compared to culprit-only treatment in patients with ST-segment elevation myocardial infarction (STEMI) and multivessel disease (MVD) at one year. The aim of this study was to investigate the outcome at three years, together with cost analysis of this strategy. METHODS AND RESULTS After primary percutaneous coronary intervention (PCI), 885 patients with STEMI and MVD were randomised (1:2 ratio) to FFR-guided complete revascularisation (295 patients) or infarct-related artery (IRA)-only treatment (590 patients). After 36 months, the primary endpoint (composite of death, myocardial infarction, revascularisation, stroke) occurred significantly less frequently in the FFR-guided complete revascularisation group: 46/295 patients (15.6%) versus 178/590 patients (30.2%) (HR 0.46, 95% CI: 0.33-0.64; p

Uvod: Pocet starsich nemocných (≥ 75 let) hospitalizovaných pro akutni koronarni syndrom (AKS) narůsta. Chybi dostatek informaci o tom, jak se v průběhu casu změnila adherence k doporuceným lecebným strategiim u těchto pacientů.Cil: Analyzovat trendy v lecbě a osudu starsich (≥ 75 let) pacientů s AKS na zakladě udajů ziskaných ze dvou ceských registrů provedených v odstupu deseti let.Metody a výsledky: V teto studii byly použity udaje z registrů CZECH-1 a CZECH-3. V uvedených registrech byla shromažďovana data na podzim roku 2005, resp. na podzim roku 2015, o 1 952, resp. 1 754 neselektovaných pacientech. Vsichni pacienti byli hospitalizovani se vstupni diagnozou AKS. Do registru CZECH-1 bylo zařazeno 490 (25,7 %) starsich pacientů, do registru CZECH-3 pak 484 (28,1 %) starsich pacientů (p = 0,045) průměrneho věku 80,6 ± 4 roky, resp. 82,1 ± 5 let (p < 0,001). Diagnoza AKS byla potvrzena u 345 (72 %), resp. u 352 (73,6 %) starsich pacientů (p = 0,781). V registru CZECH-3 bylo ve srovnani s registrem CZECH-1 zaznamenano vice provedených perkutannich koronarnich intervenci (65,2 %, resp. 54,8 %; p < 0,001), castějsi podavani dualni protidestickove lecby, inhibitorů angiotensin konvertujiciho enzymu (ACE) a statinů v průběhu lecby. Co se týce nemocnicni mortality starsich pacientů s potvrzeným AKS, nebyly mezi registry zaznamenany žadne rozdily (8,2 %, resp. 10,4 %; p = 0,790).Zavěr: Podil starsich pacientů s AKS a jejich průměrný věk narůsta. I když bylo v adherenci k lecbě podle doporucených postupů u teto podskupiny pacientů v průběhu casu zaznamenano zlepseni, ke změně v nemocnicni mortalitě nedoslo.

The paper deals with handling multiple subdomains per computational core in the PERMON toolbox, namely in the PermonFLLOP module, to fully exploit the potential of the Total Finite Element Tearing and Interconnecting (TFETI) domain decomposition method (DDM). Most authors researching FETI methods present weak parallel scalability with one subdomain assigned to each computational core, and call it just parallel scalability. Here we present an extension showing the data of more than one subdomain being held by each MPI process. Numerical experiments demonstrate the theoretically supported fact that for the given problem size and number of processors, the increased number of subdomains leads to better conditioning of the system operator, and hence faster convergence. Moreover, numerical, memory, strong parallel, and weak parallel scalability is reported, and optimal numbers of subdomains per core are examined. Finally, new PETSc matrix types dealing with the aforementioned extension are introduced.

Background Compare-Acute trial showed a 1-year superior outcome of FFR-guided acute complete revascularization (FFR-CR) compared to culprit-lesion-only revascularization (CLO) in patients presenting with ST-segment elevation myocardial infarction (STEMI) and multi-vessel disease (MVD). Long-term outcome results are unknown. Purpose To evaluate if FFR-CR strategy is superior to CLO strategy in terms of outcome at 3 year follow-up. Methods Compare-Acute is a multicenter, investigator-initiated prospective randomized controlled trial that involved 24 sites. Patients with STEMI and MVD were randomized, after successful primary PCI towards FFR-CR or CLO treatment strategies with a 1:2 ratio (295 pts vs 590 pts). All stenosis ≥50% in the non-infarct artery were investigated by FFR in both arms. In the FFR-CR arm, all non-culprit (NC) lesions with a FFR ≤0.80 were treated by PCI. In the CLO arm pts underwent blinded FFR procedure of the NC lesions. Further treatment of these lesions was based on symptoms and/or ischemia testing during follow-up with an allowed treatment window of 45 days. The primary endpoint was defined as a composite of all-cause mortality, non-fatal myocardial infarction, any revascularization and cerebrovascular events (MACCE) at 12 months. The major secondary endpoint is MACCE from both strategies up to 3-year follow-up. Results 1-year clinical outcomes have already been presented and published. At 36 months the composite end-point of MACCE occurred in 46 patients in the FFR-CR group vs 178 patients in the CLO group (15.6% vs 30.2%; HR 0.46, 95% CI 0.29–0.59; p MACCE-free survival at 3 years Conclusion With this analysis of the Compare-Acute trial we confirm that the benefit of a FFR-guided complete revascularization strategy in patients with STEMI and MVD is maintained at 3 years of follow-up. This difference is mainly driven by increased revascularizations in the CLO arm, but also by increased incidence of MI in the CLO subgroup with FFR+ lesions that were left untreated.

This paper deals with investigating l1-loss and l2-loss l2-regularized Support Vector Machines implemented in PermonSVM – a part of our PERMON toolbox. The loss functions quantify error between predicted and correct classifications of samples in cases of non-perfectly linearly separable classifications. In numerical experiments, we study properties of Hessians related to performance score of models and analyze convergence rate on 4 public available datasets. The Modified Proportioning and Reduced Gradient Projection algorithm is used as a solver for the dual Quadratic Programming problem resulting from Support Vector Machines formulations.

Detections of material regions on CT-scans of solids are commonly treated manually by an expert. Although such manual detections have many advantages, some amount of human error is also incorporated. Moreover, expert opinions may vary significantly. We present an application of the k-means++ clustering as an alternative option to manual way of material area detections. k-means++ clustering is derived from k-means (the method of vector quantization, originally from signal processing), popular for cluster analysis in data mining and image processing communities. The algorithm s main advantages are its simple implementation and fast convergence to a local optimum of an objective function. We benchmark the suggested approach on transverse CT-scans of a fibre-reinforced concrete solid. Moreover, we introduce a technique for processing air distribution, such that the appropriate pixels detected as the pixels of air are converted into pixels representing concrete. The technique is based on the connected component algorithm. Benchmark and results of proposed method conclude the paper.

Bifurkacni leze jsou poměrně castým koronarografickým nalezem, jejichž řeseni je, navzdory pokrokům v instrumentariu i novým technikam, stale technicky a casově narocne. Je zaroveň spojeno s horsimi proceduralnimi i dlouhodobými klinickými výsledky. Dedikovane bifurkacni stenty byly vyvinuty s cilem zjednodusit intervencni lecbu bifurkacnich lezi a zlepsit jeji casne i dlouhodobe výsledky. V nasi kazuistice prezentujeme připad pacienta se subakutnim Q infarktem myokardu předni stěny s kritickou stenozou ve větveni kmene leve věncite tepny, který byl lecen primarni perkutanni koronarni intervenci (PCI) s použitim dedikovaneho bifurkacniho stentu Tryton Side Branch s velmi dobrým angiografickým a klinickým výsledkem.

Implementation, performance, and scalability results of communication layer for Total FETI and Hybrid Total FETI solver.In HTFETI several neighboring subdomains aggregated into clusters. This reduces the size of coarse problem and improves scalability.Optimization of nearest neighbor communication - global gluing matrix.Implementation of communication hiding and avoiding techniques inside the communication layerBenchmarks - elastic 3D cube up to 1.6 billion DOF and realistic car engine benchmark.Large test executed on Total FETI to see the real potential of communication layer on smaller clusters. This paper describes the implementation, performance, and scalability of our communication layer developed for Total FETI (TFETI) and Hybrid Total FETI (HTFETI) solvers. HTFETI is based on our variant of the Finite Element Tearing and Interconnecting (FETI) type domain decomposition method. In this approach a small number of neighboring subdomains is aggregated into clusters, which results in a smaller coarse problem. To solve the original problem TFETI method is applied twice: to the clusters and then to the subdomains in each cluster.The current implementation of the solver is focused on the performance optimization of the main CG iteration loop, including: implementation of communication hiding and avoiding techniques for global communications; optimization of the nearest neighbor communication - multiplication with a global gluing matrix; and optimization of the parallel CG algorithm to iterate over local Lagrange multipliers only.The performance is demonstrated on a linear elasticity 3D cube and real world benchmarks.

The paper investigates strategies for expansion of active set that can be employed by the MPRGP algorithm. The standard MPRGP expansion uses a projected line search in the free gradient direction with a fixed step length. Such a scheme is often too slow to identify the active set, requiring a large number of expansions. We propose to use adaptive step lengths based on the current gradient, which guarantees the decrease of the unconstrained cost function with different gradient-based search directions. Moreover, we also propose expanding the active set by projecting the optimal step for the unconstrained minimization. Numerical experiments demonstrate the benefits (up to 78% decrease in the number of Hessian multiplications) of our expansion step modifications on two benchmarks – contact problem of linear elasticity solved by TFETI and machine learning problems of SVM type, both implemented in PERMON toolbox.

We are focusing on the algorithms for solving the large-scale convex optimization problem in linear elasticity contact problems discretized by Finite Element method (FEM). The unknowns of the problem are the displacements of the FEM nodes, the corresponding objective function is defined as a convex quadratic function with symmetric positive definite stiffness matrix and additional non-linear term representing the friction in contact. The feasible set constraints the displacement subject to non-penetration conditions. The dual formulation of this optimization problem is well-known as a Quadratic Programming (QP) problem and can be considered as a most basic non-linear optimization problem. Understanding these problems and the development of efficient algorithms for solving them play the crucial role in the large-scale problems in practical applications. We shortly review the theory and examine the behavior and the efficiency of Spectral Projected Gradient method modified for QP problems (SPG-QP) on the solution of a toy example in MATLAB environment. Web of Science 12 20 art. no. 8674

This paper deals with scalability improvements of the FETI (Finite Element Tearing and Interconnecting) domain decomposition method solving elliptic PDEs. The main bottleneck of FETI is the solution of a coarse problem that is part of the projector onto the natural coarse space. This paper introduces and compares two strategies for the FETI coarse problem solution. The first one is a classical solution with either direct (factorization + forward/backward substitutions) or iterative solvers (conjugate gradient and deflated conjugate gradient methods). The second one is the assembly of an explicit inverse using a direct solver with the coarse problem solution realised by dense matrix-vector products. MPI subcommunicators are employed to increase arithmetic intensity and, crucially, to decrease the communication cost. PERMON library for quadratic programming implementing the Total FETI variant of FETI was used for the numerical experiments.

BackgroundSuspicion of acute coronary syndrome (ACS) is one of the most common reasons for hospital admission. However, ACS is not confirmed in a high proportion of these patients during hospitalization. Very few details exist about these patients.AimTo evaluate the clinical characteristics and outcomes of hospitalized patients with a suspicion for ACS that has not been confirmed and compare these results with patients with confirmed ACS.Methods and resultsData were used from the CZECH-1 and CZECH-2 registries, collected in November 2005 and October–November 2012. Both registries contain data from all consecutive patients who have been hospitalized with an initial diagnosis of ACS. ACS was not confirmed during hospitalization in 578 of 1921 patients (30.1%) in the CZECH-1 registry and in 372 of 1221 (30.5%) in the CZECH-2 registry. In both registries, higher proportions of females (52 vs. 36%; p