Accurate geological modelling of features such as faults, fractures or erosion requires grids that are flexible with respect to geometry. Such grids generally contain polyhedral cells and complex grid-cell connectivities. The grid representation for polyhedral grids in turn affects the efficient implementation of numerical methods for subsurface flow simulations. It is well known that conventional two-point flux-approximation methods are only consistent for K-orthogonal grids and will, therefore, not converge in the general case. In recent years, there has been significant research into consistent and convergent methods, including mixed, multipoint and mimetic discretisation methods. Likewise, the so-called multiscale methods based upon hierarchically coarsened grids have received a lot of attention. The paper does not propose novel mathematical methods but instead presents an open-source Matlab® toolkit that can be used as an efficient test platform for (new) discretisation and solution methods in reservoir simulation. The aim of the toolkit is to support reproducible research and simplify the development, verification and validation and testing and comparison of new discretisation and solution methods on general unstructured grids, including in particular corner point and 2.5D PEBI grids. The toolkit consists of a set of data structures and routines for creating, manipulating and visualising petrophysical data, fluid models and (unstructured) grids, including support for industry standard input formats, as well as routines for computing single and multiphase (incompressible) flow. We review key features of the toolkit and discuss a generic mimetic formulation that includes many known discretisation methods, including both the standard two-point method as well as consistent and convergent multipoint and mimetic methods. Apart from the core routines and data structures, the toolkit contains addon modules that implement more advanced solvers and functionality. Herein, we show examples of multiscale methods and adjoint methods for use in optimisation of rates and placement of wells.

Abstract-Patients with combined hyperlipemia have lipid abnormalities associated with an increased tendency to develop atherosclerosis and thrombosis. This tendency may be accelerated during postprandial hyperlipemia. In the present double-blind parallel study, 41 patients with combined hyperlipemia and serum triacylglycerols between 2.0 and 15.0 mmol/L and serum total cholesterol Ͼ5.3 mmol/L at the end of a 3-month dietary run-in period were treated with simvastatin at 20 mg/d for at least 10 weeks; patients were then randomized into 2 groups receiving simvastatinϩ-3 fatty acids at 3.36 g/d or placebo (corn oil) for an additional 5 weeks. Hemostatic variables that have been associated with increased thrombotic tendency were evaluated with subjects in the fasting state and during postprandial hyperlipemia before and after combined treatment. Supplementation of -3 fatty acid reduced tissue factor pathway inhibitor antigen (PϽ0.05) in the fasting state, reduced the degree of postprandial hyperlipemia (PϽ0.005), and reduced activated factor VII concentration appearing during postprandial hyperlipemia. In conclusion, -3 fatty acids given in addition to simvastatin to patients with combined hyperlipemia reduced the free tissue factor pathway inhibitor fraction in the fasting state and inhibited the activation of factor VII occurring during postprandial lipemia, thus representing a potential beneficial effect on the hemostatic risk profile in this patient group. Key Words: combined hyperlipemia Ⅲ postprandial hyperlipemia Ⅲ hemostatic risk factors R upture of an atherosclerotic plaque with subsequent formation of an occlusive thrombus is the major cause of myocardial infarction. 1 The extrinsic coagulation system has been suggested to play a crucial role in the initiation of blood coagulation in atherosclerotic disease. 2 Tissue factor (TF) is an integral membrane protein that functions as a cofactor to enhance the proteolytic activity of activated factor VII (FVII a ) toward factor IX and factor X, which leads to the formation of a fibrin clot. 3 TF is synthesized in perturbed endothelial cells, 4 which may render them thrombogenic, and is also present in the cores of atherosclerotic plaques. 5 Thus, transient exposure of TF at the surface of atherosclerotic plaque or perturbed endothelial cells may cause low-grade triggering of blood coagulation. TF pathway inhibitor (TFPI) is a potent inhibitor of TF-induced coagulation, which exerts its function by neutralizing the catalytic activity of factor Xa and by feedback inhibition of the TF-FVII a complex. 6,7 Factor VII (FVII) is the first enzyme involved in the extrinsic pathway of blood coagulation. The major proportion of FVII circulates in plasma in the zymogen form, whereas low but significant levels appear in an activated form (FVII a ), which serves as the primer for triggering the clotting cascade. 8 -10 In epidemiological studies, the coagulation activity of factor VII (FVII c ) is positively correlated to serum triglycerides 11 (less consistently to serum chol...

The Bogoliubov equations are solved for a three-dimensional Bose-Einstein condensate containing a doubly quantized vortex, trapped in a harmonic potential. Complex frequencies, signifying dynamical instability, are found for certain ranges of parameter values. The existence of alternating windows of stability and instability, respectively, is explained qualitatively and quantitatively using variational calculus and direct numerical solutions. It is seen that the windows of stability disappear in the limit of a cigar-shaped condensate, which is consistent with recent experimental results on the lifetime of a doubly quantized vortex in that regime.͑r 2 + 2 z 2 ͒. ͑2͒The anisotropy of the trap is governed by the ratio between the axial and radial trapping strengths, so that when is larger than unity, the atomic cloud resembles a pancake and

We present MRST-AD, a free, open-source framework written as part of the Matlab Reservoir Simulation Toolbox and designed to provide researchers with the means for rapid prototyping and experimentation for problems in reservoir simulation. The article outlines the design principles and programming techniques used and explains in detail the implementation of a full-featured, industry-standard black-oil model on unstructured grids. The resulting simulator has been thoroughly validated against a leading commercial simulator on benchmarks from the SPE Comparative Solution Projects, as well as on a real-field model (Voador, Brazil). We also show in detail how practitioners can easily extend the black-oil model with new constitutive relationships, or additional features such as polymer flooding, thermal and reactive effects, and immediately benefit from existing functionality such as constrained-pressure-residual (CPR) type preconditioning, sensitivities and adjoint-based gradients. Technically, MRST-AD combines three key features: (i) a highly vectorized scripting language that enables the user to work with high-level mathematical objects and continue to develop a program while it runs; (ii) a flexible grid structure that enables simple construction of discrete differential operators; and (iii) automatic differentiation that ensures that no analytical derivatives have to be programmed explicitly as long as the discrete flow equations and constitutive relationships are implemented as a sequence of algebraic operations. We have implemented a modular, efficient framework for implementing and comparing different physical models, discretizations, and solution strategies by combining imperative and object-oriented paradigms with functional programming. The toolbox also offers additional features such as upscaling and grid coarsening, consistent discretizations, multiscale solvers, flow diagnostics and interactive visualization.

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Background: Autonomic modulation of heart rhythm is thought to influence the pathophysiology of myxomatous mitral valve disease (MMVD).Hypotheses: (1) Holter-derived variables reflecting autonomic modulation of heart rhythm change with MMVD severity in Cavalier King Charles Spaniels (CKCS); (2) Holter-derived variables can identify MMVD severity in CKCS; and (3) Holter-derived variables in CKCS in congestive heart failure (CHF) secondary to MMVD differ from those in dogs of other breeds in CHF.Animals: Ninety privately owned dogs: 70 CKCS with variable MMVD severity and 20 non-CKCS in CHF secondary to MMVD.Methods: Dogs were prospectively recruited and divided into 5 MMVD severity groups based on history, breed, and physical and echocardiographic examination findings. Holter-derived variables included heart rate variability (HRV), heart rate (HR), and arrhythmia evaluated from 24-hour Holter recordings.Results: In CKCS, 18 of 26 HRV (all P < .0002) and 3 of 9 arrhythmia (all P < .0004) variables decreased with increasing MMVD, whereas minimum and mean HR (all P < .0001) increased with increasing MMVD severity. An arrhythmia variable representing sinus arrhythmia ("premature normals") (P < .0001) and the HRV variable triangular index (TI) (P < .0001) could distinguish CKCS with moderate or severe mitral regurgitation from CKCS in CHF in specific intervals. Among dogs in CHF, Holter-derived variables did not differ among breeds.Conclusions and Clinical Importance: In CKCS, Holter-derived variables changed with MMVD severity. "Premature normals" and TI showed diagnostic potential. Breed differences were not seen among dogs in CHF secondary to MMVD.

Abstract. Nordøy A, Bønaa KH, Nilsen H, Berge R, Hansen JB, Ingebretsen OC (University of Tromsø, Tromsø, Norway). Effects of Simvastatin and omega-3 fatty acids on plasma lipoproteins and lipid peroxidation in patients with combined hyperlipidemia. J Intern Med 1998; 243: 163-70.Objectives. Patients with combined hyperlipidemia are at increased risk for development of coronary heart disease. The purpose of this study was to evaluate the efficiency and the safety of treatment with Simvastatin and omega-3 fatty acids in patients with this lipid disorder. Design. A double-blind placebo controlled, randomized study evaluating the effects of Simvastatin separately and in combination with omega-3 fatty acids in 41 healthy patients with defined hyperlipidemia. After a 16 weeks dietary run-in period the patients were treated in periods of 5 weeks. Results.As expected Simvastatin (20 mg day Ϫ1 ) reduced serum total cholesterol, triacylglycerols, apolipoproteins B and E and increased HDL-cholesterol and apolipoprotein A 1 . Addition of omega-3 fatty acids (4 g day Ϫ1 ) further decreased serum triacylglycerols (P ϭ 0.007), total cholesterol (P ϭ 0.052) and apolipoprotein E (P ϭ 0.035). No significant changes attributable to supplementation of polyunsaturated fatty acids on the content of lipid peroxides in plasma and in the various lipoprotein fractions were observed. Conclusions. The combined treatment of Simvastatin and omega-3 fatty acids seems to be an efficient and safe alternative for patients with combined hyperlipidemia.

Modeling geological carbon storage represents a new and substantial challenge for the subsurface geosciences. To increase understanding and make good engineering decisions, containment processes and large-scale storage operations must be simulated in a thousand-year perspective. Large differences in spatial and temporal scales make it prohibitively expensive to compute the fate of injected CO 2 using traditional 3D simulators. Instead, accurate forecast can be computed using simplified models that are adapted to the specific setting of the bouyancy-driven migration of the light fluid phase. This paper presents a family of vertically integrated models for studying the combined large-scale and long-term effects of structural, residual, and solubility trapping of CO 2 . The models are based on an assumption of a sharp interface separating CO 2 and brine and can provide a detailed inventory of the injected CO 2 volumes over periods of thousands of years within reasonable computational time. To be compatible with simulation tools used in industry, the models are formulated in a black-oil framework. The models are implemented in MRST-co2lab, which is an open community