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This paper is interested in the mathematical modeling and approximation of the turbulent flow with strong anisotropy for the case of flow in a rack station. Turbulent models based on Boussinesq eddy viscosity assumption are traditionally employed for the solution of these types of flows. Linear eddy viscosity model and the assumption of isotropic Reynolds stress tensor are typically used in many cases. This leads to certain limitations in the cases of either separated flow or flow with significant curvature of the mean flow. The application of full Reynolds stress model is suitable for this case but it introduces at least seven additional equations and the model has much higher demand for computing time, grid parameters and discretization schemes. Therefore the Explicit Algebraic Reynolds Stress Model (EARSM) is used here. This model is based on two equations k – omega turbulence model with the nonlinear eddy viscosity model and explicit terms for anisotropic parts of the Reynolds stress tensor. The computational requirements are similar to the standard k – omega model. The numerical and experimental results from PIV measurement are compared.

Engineering geological models (EGMs) comprise both conceptual ideas and observational data. The observational data are associated with aleatory uncertainty which can be reduced by acquiring more observations. The conceptual ideas are associated with epistemic uncertainty which can be reduced only if more knowledge is incorporated into the model. The conceptual ideas are the core of any EGM and provide the framework for the evaluation of the observational data. The most powerful capability of an EGM is the ability to anticipate what might be present at a project site and evaluate how the ground could adversely affect the project, i.e. when developed correctly, an EGM allows an evaluation of what might reasonably be foreseen at a site by an experienced contractor. This requires sophisticated conceptualization at an early stage in the project to anticipate what might be in the ground. Consequently, EGMs are much more than visualizations; they should represent an understanding of the geological conditions that are of engineering significance to the project, provide the framework for assembling engineering geological knowledge, support good geotechnical engineering decisions and allow an evaluation of potential geotechnical risks and possible project opportunities. Thematic collection: This article is part of the Ground models in engineering geology and hydrogeology collection available at: https://www.lyellcollection.org/cc/Ground-models-in-engineering-geology-and-hydrogeology [ABSTRACT FROM AUTHOR]

Heparin induced thrombocytopenia (HIT) represents a very serious complication of heparin therapy associated with high morbidity and/or mortality. HIT is caused by generation of antibodies against macromolecular complexes of heparin/platelet factor 4 resulting in activation of platelets, monocytes, endothelium and neutrophils with subsequent high thrombin generation and induction of a hypercoagulable state. Therapy with heparins must be interrupted and alternative non-heparin antithrombotics must be introduced. The dia-gnosis of HIT is based on clinical findings namely the so called 4T score and laboratory tests. Immunological tests have a high negative predictive value in excluding HIT. In positive cases, the dia-gnosis must be confirmed by functional tests. Novel developments in the therapy of HIT include the introduction of the new direct oral anticoagulants. [ABSTRACT FROM AUTHOR]

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Thrombotic microangiopathies are a group of heterogeneous disorders characterized by disseminated microthrombosis in arterioles and capillaries resulting in consumption of platelets and microangiopathic haemolytic anaemia with potential end organ injury. The diagnosis may be complicated because of overlapping presentations of these disorders. Thrombotic thrombocytopenic purpura (TTP) may be diagnosed on the basis of severely decreased ADAMTS13 activity (a disintegrin and metalloprotease with thrombospondin motif 13), which is reduced below 10% with possible detection of an IgG inhibitor. The inherited form of TTP (Upshaw-Schulman syndrome) involves mutations of the ADAMTS13 gene with no inhibitor. Severe reduction of ADAMTS13 is activity leads to an increased concentration of ultra-large von Willebrand factor multimers with potent affinity to platelet glycoprotein Ib (GPIb) resulting in platelet aggregation. Treatment of choice of acquired TTP includes therapeutic plasma exchange with immunomodulation using corticoids and/or rituximab. The inherited form may be treated by plasma infusion only. Haemolytic-uremic syndrome is induced by shiga toxin producing Escherichia coli mainly in young children (typical haemolytic uremic syndrome). Shiga toxins are toxic to the endothelium and activate platelets. In such cases, there is serious impairment of renal functions often necessitating haemodialysis and even renal transplantation in some cases. The manifestation of typical haemolytic uremic syndrome is preceded by haemorrhagic diarrhoea. Therapy is mainly supportive. Atypical haemolytic uremic syndromes are induced by inherited disorders of the alternative pathway of complement activation due to mutations in genes of regulatory complement proteins. Some patients have factor H inhibitors. The main therapeutic approach in these forms is the administration of the complement factor C5 inhibitor eculizumab. Secondary forms of thrombotic microangiopathies are mainly seen in association with disseminated malignancies, pregnancy, auto-aggressive disorders, cobalamin C defect (cblC), infections, following solid organ or haematopoietic stem cells transplantation, malignant hypertension and may also be drug induced. The main differential diagnosis involves exclusion of disseminated intravascular coagulation associated with prolongation of global coagulation tests- aPTT and PT. [ABSTRACT FROM AUTHOR]