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  1. Von Willebrand disease protects against arterial thrombosis

    NARCIS (Netherlands)

    Sanders, Y.V.; Eikenboom, J.C.; De Wee, E.M.; Van Der Bom, J.G.; Cnossen, M.H.; Degenaar-Dujardin, M.E.; Fijnvandraat, K.; Kamphuisen, P.W.; Laros-Van Gorkum, B.A.; Meijer, K.; Mauser -Bunschoten, E.P.; Leebee k, F.W.

    Background and Aims: Von Willebrand disease (VWD) is caused by reduced levels of or dysfunctional von Willebrand factor (VWF) and is characterized by a bleeding tendency. It is well known that individuals with high VWF levels have a higher risk for arterial thrombosis. Although it has never been

  2. Von Willebrand protein binds to extracellular matrices independently of collagen.

    OpenAIRE

    Wagner, D D; Urban-Pickering, M; Marder, V J

    1984-01-01

    Von Willebrand protein is present in the extracellular matrix of endothelial cells where it codistributes with fibronectin and types IV and V collagen. Bacterial collagenase digestion of endothelial cells removed fibrillar collagen, but the pattern of fibronectin and of von Willebrand protein remained undisturbed. Exogenous von Willebrand protein bound to matrices of different cells, whether rich or poor in collagen. von Willebrand protein also decorated the matrix of cells grown in the prese...

  3. Doença de von Willebrand e anestesia Enfermedad de von Willebrand y anestesia Von Willebrand's disease and anesthesia

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    Fabiano Timbó Barbosa

    2007-06-01

    Full Text Available JUSTIFICATIVA E OBJETIVOS: A doença de von Willebrand ocorre devido à mutação no cromossomo 12 e é caracterizada por deficiência qualitativa ou quantitativa do fator de von Willebrand. A diversidade de mutações leva ao aparecimento das mais variadas manifestações clínicas possibilitando a divisão dos pacientes em vários tipos e subtipos clínicos. A coagulopatia se manifesta basicamente através da disfunção plaquetária associada à diminuição dos níveis séricos do fator VIII coagulante. O objetivo dessa revisão foi mostrar os cuidados relacionados aos pacientes portadores da doença de von Willebrand durante o período perioperatório. CONTEÚDO: Foram definidas as características da doença de von Willebrand quanto à fisiopatologia, à classificação, ao diagnóstico laboratorial, ao tratamento atual e aos cuidados com o manuseio do paciente no período perioperatório. CONCLUSÕES: A doença de von Willebrand é o distúrbio hemorrágico hereditário mais comum, porém ela é subdiagnosticada pela complexidade da própria doença. A correta classificação do paciente, o uso apropriado da desmopressina e a transfusão do fator de von Willebrand são medidas fundamentais para a realização do procedimento anestésico bem-sucedido.JUSTIFICATIVA Y OBJETIVOS: La enfermedad de von Willebrand ocurre debido a la mutación en el cromosoma 12 y se caracteriza por la deficiencia cualitativa o cuantitativa del factor de von Willebrand. La diversidad de mutaciones conlleva al aparecimiento de las más variadas manifestaciones clínicas posibilitando la división de los pacientes en varios tipos y subtipos clínicos. La coagulopatía se manifiesta básicamente a través de la disfunción plaquetaria asociada con la disminución de los niveles séricos del factor VIII coagulante. El objetivo de esa revisión fue mostrar los cuidados relacionados con las pacientes portadoras de la enfermedad de von Willebrand durante el per

  4. Active Von Willebrand Factor, thrombocytopenia and thrombosis

    NARCIS (Netherlands)

    Hulstein, J.J.J.

    2006-01-01

    Platelets and von Willebrand factor (VWF) are unable to interact in circulation. To induce an interaction, a conversion of VWF to a platelet-binding conformation is required. At higher shear stresses, the first step in thrombus formation is binding of VWF to the subendothelium. This results in

  5. The Molecular Genetics of von Willebrand Disease

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    Ergül Berber

    2012-12-01

    Full Text Available Quantitative and/or qualitative deficiency of von Willebrand factor (vWF is associated with the most common inherited bleeding disease von Willebrand disease (vWD. vWD is a complex disease with clinical and genetic heterogeneity. Incomplete penetrance and variable expression due to genetic and environmental factors contribute to its complexity. vWD also has a complex molecular pathogenesis. Some vWF gene mutations are associated with the affected vWF biosynthesis and multimerization, whereas others are associated with increased clearance and functional impairment. Moreover, in addition to a particular mutation, type O blood may result in the more severe phenotype. The present review aimed to provide a summary of the current literature on the molecular genetics of vWD.

  6. The molecular genetics of von Willebrand disease.

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    Berber, Ergül

    2012-12-01

    Quantitative and/or qualitative deficiency of von Willebrand factor (vWF) is associated with the most common inherited bleeding disease von Willebrand disease (vWD). vWD is a complex disease with clinical and genetic heterogeneity. Incomplete penetrance and variable expression due to genetic and environmental factors contribute to its complexity. vWD also has a complex molecular pathogenesis. Some vWF gene mutations are associated with the affected vWF biosynthesis and multimerization, whereas others are associated with increased clearance and functional impairment. Moreover, in addition to a particular mutation, type O blood may result in the more severe phenotype. The present review aimed to provide a summary of the current literature on the molecular genetics of vWD. None declared.

  7. Von Willebrand factor indicates bacterial translocation, inflammation, and procoagulant imbalance and predicts complications independently of portal hypertension severity.

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    Mandorfer, M; Schwabl, P; Paternostro, R; Pomej, K; Bauer, D; Thaler, J; Ay, C; Quehenberger, P; Fritzer-Szekeres, M; Peck-Radosavljevic, M; Trauner, M; Reiberger, T; Ferlitsch, A

    2018-04-01

    Elevated plasma von Willebrand factor antigen (vWF) has been shown to indicate the presence of clinically significant portal hypertension, and thus, predicts the development of clinical events in patients with cirrhosis. To investigate the impact of bacterial translocation and inflammation on vWF, as well as the association between vWF and procoagulant imbalance. Moreover, we assessed whether vWF predicts complications of cirrhosis, independent of the severity of portal hypertension. Our study population comprised 225 patients with hepatic venous pressure gradient (HVPG) ≥ 10 mm Hg without active bacterial infections or hepatocellular carcinoma. vWF correlated with markers of bacterial translocation (lipopolysaccharide-binding protein [LBP; ρ = 0.201; P = 0.021]), inflammation (interleukin 6 [IL-6; ρ = 0.426; P protein [CRP; ρ = 0.249; P protein C ratio; ρ = 0.507; P model for transplant-free mortality. Finally, the independent prognostic value of vWF/CRP groups for mortality was confirmed by competing risk analysis. Our results demonstrate that vWF is not only a marker of portal hypertension but also independently linked to bacterial translocation, inflammation and procoagulant imbalance, which might explain its HVPG-independent association with most clinical events. Prognostic groups based on vWF/CRP efficiently discriminate between patients with a poor 5-year survival and patients with a favourable prognosis. © 2018 John Wiley & Sons Ltd.

  8. Value of Von Willebrand Factor as a Predictor for Osteoporosis Development in Women with Hypothyroidism

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    I.V. Pankiv

    2015-08-01

    Full Text Available The paper presents the study of the value of von Willebrand factor as a marker of endothelial dysfunction for osteoporosis development and for prediction of risk of its formation in women with hypothyroidism. Postmenopausal women with hypothyroidism have significant increase of von Willebrand factor at lumbar osteopenia. High concentrations of von Willebrand factor in women with hypothyroidism follows to consider it as a predictor for osteoporosis development. Increased level of С-reactive protein belongs to the unfavorable prognostic signs in relation to the decline of bone mineral density for patients with primary hypothyroidism.

  9. Translational Medicine Advances in von Willebrand Disease

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    Lillicrap, David

    2014-01-01

    Following the recognition of von Willebrand disease (VWD) in 1926 and the cloning of the gene for von Willebrand factor (VWF) in 1985, significant advances have been made in our fundamental knowledge of both the disease and the protein. Some of this new knowledge has also begun to impact the clinical management of VWD. First, the progressive increase in our understanding of the molecular genetic basis of VWD has resulted in rational applications of molecular testing to complement the current range of phenotypic tests for VWD. These molecular genetic strategies are most effectively directed at the prenatal diagnosis of type 3 VWD and confirmatory testing for types 2B and 2N disease. In contrast, the use of molecular testing to clarify the diagnosis of type 1 VWD is of marginal benefit, at best. In terms of VWD therapies, a new recombinant VWF concentrate has recently completed successful clinical trials and is now awaiting more widespread application. There have even been some pre-clinical successes with VWF gene transfer although the clinical rationale for this therapeutic strategy needs careful consideration. Much more remains to be learnt about the biology of VWF and further translational advances for the enhancement of VWD care will inevitably be realized. PMID:23809112

  10. Of von Willebrand factor and platelets.

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    Bryckaert, Marijke; Rosa, Jean-Philippe; Denis, Cécile V; Lenting, Peter J

    2015-01-01

    Hemostasis and pathological thrombus formation are dynamic processes that require multiple adhesive receptor-ligand interactions, with blood platelets at the heart of such events. Many studies have contributed to shed light on the importance of von Willebrand factor (VWF) interaction with its platelet receptors, glycoprotein (GP) Ib-IX-V and αIIbβ3 integrin, in promoting primary platelet adhesion and aggregation following vessel injury. This review will recapitulate our current knowledge on the subject from the rheological aspect to the spatio-temporal development of thrombus formation. We will also discuss the signaling events generated by VWF/GPIb-IX-V interaction, leading to platelet activation. Additionally, we will review the growing body of evidence gathered from the recent development of pathological mouse models suggesting that VWF binding to GPIb-IX-V is a promising target in arterial and venous pathological thrombosis. Finally, the pathological aspects of VWF and its impact on platelets will be addressed.

  11. Elevated Factor VIII and von Willebrand Factor Levels Predict Unfavorable Outcome in Stroke Patients Treated with Intravenous Thrombolysis

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    Noémi Klára Tóth

    2018-01-01

    Full Text Available IntroductionPlasma factor VIII (FVIII and von Willebrand factor (VWF levels have been associated with the rate and severity of arterial thrombus formation and have been linked to outcomes following thrombolytic therapy in acute myocardial infarction patients. Here, we aimed to investigate FVIII and VWF levels during the course of thrombolysis in acute ischemic stroke (AIS patients and to find out whether they predict long-term outcomes.Materials and methodsStudy population included 131 consecutive AIS patients (median age: 69 years, 60.3% men who underwent i.v. thrombolysis with recombinant tissue plasminogen activator (rt-PA. Blood samples were taken on admission, 1 and 24 h after rt-PA administration to measure FVIII activity and VWF antigen levels. Neurological deficit of patients was determined according to the National Institutes of Health Stroke Scale (NIHSS. ASPECT scores were assessed using computer tomography images taken before and 24 h after thrombolysis. Intracranial hemorrhage was classified according to the European Cooperative Acute Stroke Study (ECASS II criteria. Long-term functional outcome was determined at 90 days after the event by the modified Rankin scale (mRS.ResultsVWF levels on admission were significantly elevated in case of more severe AIS [median and IQR values: NIHSS <6:189.6% (151.9–233.2%; NIHSS 6–16: 199.6% (176.4–250.8%; NIHSS >16: 247.8% (199.9–353.8%, p = 0.013]; similar, but non-significant trend was observed for FVIII levels. FVIII and VWF levels correlated well on admission (r = 0.748, p < 0.001 but no significant correlation was found immediately after thrombolysis (r = 0.093, p = 0.299, most probably due to plasmin-mediated FVIII degradation. VWF levels at all investigated occasions and FVIII activity before and 24 h after thrombolysis were associated with worse 24 h post-lysis ASPECT scores. In a binary backward logistic regression analysis including age, gender

  12. Prophylaxis escalation in severe von Willebrand disease: A prospective study from the von Willebrand Disease Prophylaxis Network

    NARCIS (Netherlands)

    T.C. Abshire (Thomas Calvin); J. Cox-Gill; C.L. Kempton; F.W.G. Leebeek (Frank); M. Carcao (M.); P. Kouides (P.); S. Donfield (S.); E. Berntorp

    2015-01-01

    textabstractBackground: Treatment of mucosal bleeding (epistaxis, gastrointestinal bleeding, and menorrhagia) and joint bleeding remains problematic in clinically severe von Willebrand disease (VWD). Patients are often unresponsive to treatment (e.g. desmopressin or antifibrinolytic therapy) and may

  13. von Willebrand factor, Jedi knight of the bloodstream.

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    Springer, Timothy A

    2014-08-28

    When blood vessels are cut, the forces in the bloodstream increase and change character. The dark side of these forces causes hemorrhage and death. However, von Willebrand factor (VWF), with help from our circulatory system and platelets, harnesses the same forces to form a hemostatic plug. Force and VWF function are so closely intertwined that, like members of the Jedi Order in the movie Star Wars who learn to use "the Force" to do good, VWF may be considered the Jedi knight of the bloodstream. The long length of VWF enables responsiveness to flow. The shape of VWF is predicted to alter from irregularly coiled to extended thread-like in the transition from shear to elongational flow at sites of hemostasis and thrombosis. Elongational force propagated through the length of VWF in its thread-like shape exposes its monomers for multimeric binding to platelets and subendothelium and likely also increases affinity of the A1 domain for platelets. Specialized domains concatenate and compact VWF during biosynthesis. A2 domain unfolding by hydrodynamic force enables postsecretion regulation of VWF length. Mutations in VWF in von Willebrand disease contribute to and are illuminated by VWF biology. I attempt to integrate classic studies on the physiology of hemostatic plug formation into modern molecular understanding, and point out what remains to be learned. © 2014 by The American Society of Hematology.

  14. Acquired von Willebrand syndrome: A rare disorder of heterogeneous etiology

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    P Kasatkar

    2013-01-01

    Full Text Available Context: Acquired von Willebrand syndrome (AVWS is a rare bleeding disorder that mimics the inherited form of von Willebrand disease (VWD in terms of laboratory findings and clinical presentation. Aims: To study the etiology of acquired VWD. Settings and Design: The patients referred from various hospitals in and out of Mumbai were included in the study. Materials and Methods: Six patients with AVWS diagnosed at this center over the last 10 years were analyzed against 171 patients with inherited VWD. The differential diagnosis of AVWS was made based on reduced levels of von Willebrand antigen and von Willebrand ristocetin cofactor, decrease in ristocetin induced platelet aggregation, absence of correction in mixing studies with no prior history of bleeding problems and a negative family history for bleeding disorders. Results: In three patients, the disease was associated with systematic lupus erythematosus, out of which one was also associated with Kikuchi lymphadenitis and second with autoimmune hemolytic anemia. Fourth case was associated with hypothyroidism and fifth was a case of dermatitis and vitiligo. The last patient was a case of hemophilia A with Burkitts lymphoma, who developed autoantibodies to von Willebrand factor. Except two patients, all other patients responded to immune suppressive therapy with corticosteroids, while the patient with hypothyroidism responded to oral thyroxine. Conclusion: AVWS is a rare condition and may often be missed or diagnosed as inherited disease associated with heterogeneous disease conditions.

  15. Von Willebrand Factor Gene Variants Associate with Herpes simplex Encephalitis

    Czech Academy of Sciences Publication Activity Database

    Abdelmagid, N.; Bereczky-Veress, B.; Atanur, S.; Musilová, Alena; Zídek, Václav; Saba, L.; Warnecke, A.; Khademi, M.; Studahl, M.; Aurelius, E.; Hjalmarsson, A.; Garcia-Dias, A.; Denis, C. V.; Bergström, T.; Sköldenberg, B.; Kockum, I.; Aitman, T.; Hübner, N.; Olsson, T.; Pravenec, Michal; Diez, M.

    2016-01-01

    Roč. 11, č. 5 (2016), e0155832 E-ISSN 1932-6203 R&D Projects: GA MŠk(CZ) 7E10067; GA MŠk(CZ) LL1204 Institutional support: RVO:67985823 Keywords : Von Willebrand Factor gene * Herpes simplex encephalitis * rat * humans Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.806, year: 2016

  16. No evidence for a direct effect of von Willebrand factor's ABH blood group antigens on von Willebrand factor clearance

    NARCIS (Netherlands)

    Groeneveld, D J; van Bekkum, T; Cheung, K L; Dirven, R J; Castaman, G; Reitsma, P H; van Vlijmen, B; Eikenboom, J

    BACKGROUND: One of the major determinants of von Willebrand factor (VWF) plasma levels is ABO blood group status, and individuals with blood group O have ~ 25% lower plasma levels. The exact mechanism behind this relationship remains unknown, although effects on clearance have been postulated.

  17. Diagnosis and management of von Willebrand disease: guidelines for primary care.

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    Yawn, Barbara; Nichols, William L; Rick, Margaret E

    2009-12-01

    Von Willebrand disease is an inherited condition characterized by deficiency of von Willebrand factor, which is essential in hemostasis. The National Heart, Lung, and Blood Institute has released new evidence-based guidelines for the diagnosis and management of the disease. There are three major subtypes of von Willebrand disease, classified as partial quantitative deficiency (low levels) of von Willebrand factor (type 1), qualitative deficiency (type 2), or virtually complete deficiency (type 3). Diagnosis is usually made by reviewing the patient's personal and family history of bleeding and by clinical evaluation for more common reasons for bleeding, supplemented with laboratory tests. Assessment may be used to determine bleeding risk before surgery and other invasive procedures, and to diagnose reasons for unexplained hemorrhaging. Von Willebrand factor levels of 30 IU per dL or lower are required for the definite diagnosis of inherited von Willebrand disease. Persons with levels of 30 to 50 IU per dL may not have the disease, but may need agents to increase von Willebrand factor levels during invasive procedures or childbirth. Treatment is tailored to the subtype of the disease: increasing plasma concentration of von Willebrand factor by releasing endogenous stores with desmopressin or replacing nonexistent or ineffective von Willebrand factor by using human plasma-derived, viral-inactivated concentrates; treatment is often combined with hemostatic agents that have mechanisms other than increasing von Willebrand factor. Regular prophylaxis is seldom required, and treatment is initiated before planned invasive procedures or in response to bleeding.

  18. DEEP VEIN THROMBOSIS IN PATIENT WITH VON WILLEBRAND DISEASE

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    V. A. Elykomov

    2016-01-01

    Full Text Available Objective: to identify the possible factors of thrombogenic risk and ways of its prevention in patients with von Willebrand disease.Case description. Patient X., 42 years old, who suffers from von Willebrand disease type 3 with 5-years of age. Asked on reception to the traumatologist in the polyclinic of the Regional Hospital with pain in the left hip joint. Recommended planned operative treatment in the Altai Regional Clinical Hospital. Preoperative preparation included the infusion of concentrate of von Willebrand factor and coagulation factor VIII. Operation – cement total arthroplasty of the left hip joint. In the postoperative period analgesic treatment, elastic compression of the lower extremities, iron supplements, also conducted infusion of concentrate of von Willebrand factor and coagulation factor VIII for 20 days and thromboprophylactic with dabigatran. On the 3rd day after the operation the patient revealed deep vein thrombosis of the femoral segment (floating clot.Results. The patient was operated for emergency indications in the Department of endovascular surgery – installation of venous cava filter “Volan”. Dabigatran is cancelled, appointed clexane for 3 months. In our clinical example the patient lacked risk factors of pulmonary embolism as obesity, age, smoking, prolonged immobilization, estrogen therapy. Overdose of factor VIII were not observed – the level of factor did not exceed 135 % on transfusions. At the same time, the patient was found polymorphisms in the genes ITGA2, FGB, MTHFR, MTR – heterozygote, MTRR – mutant homozygote, which may indicate the genetic factors of thrombogenic risk. Also a significant risk factor was massive surgical intervention (total hip replacement. Despite preventive measures (elastic compression, thromboprophylactic dabigatran, early activation we cannot to avoid thrombotic complications.Conclusion. This article presents a case demonstrating a thrombotic complication in patients

  19. Von Willebrand's disease in the German shepherd dog : clinical communication

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    R.G. Lobetti

    2000-07-01

    Full Text Available Two litters of Germanshepherd dogs were evaluated for a haemorrhagic tendency that was characterised by excessive bleeding from the umbilicus at birth, haemorrhage and haematoma formation at vaccination, excessive bruising, and lameness due to haemarthrosis. Platelet counts, clotting times and Von Willebrand's factor (VWF assays were assessed in all dogs. Factor VIII determination was performed in 1 puppy and its parents. Based on the clotting times and VWF assay, 6 puppies (4 male and 2 female showed type I Von Willebrand's disease (VWD, 5 (4 male and 1 female possible type II VWD, and 4 were unaffected. One puppy with possible type II VWD had very low factor VIII activity; its sire had a normal factor activity, whereas the dam was in the low-normal range. This article reports type I and possible type II VWD in 2 related litters of German shepherd dogs, the latter being rare in German shepherd dogs.

  20. Von Willebrand's Disease in Two Families of Doberman Pinschers

    OpenAIRE

    Johnstone, I. B.; Crane, S.

    1981-01-01

    The history, clinical symptoms and laboratory results in two families of Doberman pinschers with von Willebrand's disease are described. The affected animals illustrate the rather nonspecific bleeding problems that may be encountered in mild and moderate forms of this disease. In both families a bleeding diathesis was suspected when one member of the family underwent surgery with serious postoperative bleeding complications. These cases illustrate the importance of a thorough presurgical hist...

  1. Modeling Shear Induced Von Willebrand Factor Binding to Collagen

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    Dong, Chuqiao; Wei, Wei; Morabito, Michael; Webb, Edmund; Oztekin, Alparslan; Zhang, Xiaohui; Cheng, Xuanhong

    2017-11-01

    Von Willebrand factor (vWF) is a blood glycoprotein that binds with platelets and collagen on injured vessel surfaces to form clots. VWF bioactivity is shear flow induced: at low shear, binding between VWF and other biological entities is suppressed; for high shear rate conditions - as are found near arterial injury sites - VWF elongates, activating its binding with platelets and collagen. Based on parameters derived from single molecule force spectroscopy experiments, we developed a coarse-grain molecular model to simulate bond formation probability as a function of shear rate. By introducing a binding criterion that depends on the conformation of a sub-monomer molecular feature of our model, the model predicts shear-induced binding, even for conditions where binding is highly energetically favorable. We further investigate the influence of various model parameters on the ability to predict shear-induced binding (vWF length, collagen site density and distribution, binding energy landscape, and slip/catch bond length) and demonstrate parameter ranges where the model provides good agreement with existing experimental data. Our results may be important for understanding vWF activity and also for achieving targeted drug therapy via biomimetic synthetic molecules. National Science Foundation (NSF),Division of Mathematical Sciences (DMS).

  2. Von Willebrand's disease: case report and review of literature.

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    Echahdi, Hanae; El Hasbaoui, Brahim; El Khorassani, Mohamed; Agadr, Aomar; Khattab, Mohamed

    2017-01-01

    Von Willebrand Disease (VWD) is the most common human inherited bleeding disorder due to a defect of Von Willebrand Factor (VWF), which a glycoprotein crucial for platelet adhesion to the subendothelium after vascular injury. VWD include quantitative defects of VWF, either partial (type 1 with VWF levels < 50 IU/dL) or virtually total (type 3 with undetectable VWF levels) and also qualitative defects of VWF (type 2 variants with discrepant antigenic and functional VWF levels). The most bleeding forms of VWD usually do not concern type 1 patients with the mildest VWF defects (VWF levels between 30 and 50IU/dL). Von willebrand factor is a complex multimeric protein with two functions: it forms a bridge between the platelets and areas of vascular damage and it binds to and stabilizes factor VIII, which is necessary for the clotting cascade. By taking a clinical history of bleeding (mucocutaneous bleeding symptoms suggestive of a primary haemostatic disorder, a quantitative or qualitative abnormality of VWF is possible) it is important to think about VWD and to make the appropriate diagnosis. If the VWD is suspected diagnostic tests should include an activated partial thromboplastin time, bleeding time, factor VIII: C Ristocetin cofactor and vWF antigen. Additional testing of ristocetin induced plattlet adhesion (RIPA) the multimeric structure and collagen binding test and genanalysis allow diagnosing the different types of von. Willebrand Disease. The treatment of choice in mild forms is the synthetic agent desmopressin. In patients with severe type 1, type 2B, 2N and type 3 or in people who do not response to desmopressin, the appropriate treatment is a factor VIII concentrate that is rich of VWF. We report a case of infant in 27-month-old boy who had been referred due to haemorrhagic shock. His birth histories, his familie's social history and developmental milestones were unremarkable. He was born at full term with no antenatal or perinatal complications. Prior to

  3. D-dimer, factor VIII and von Willebrand factor predict a non-dipping pattern of blood pressure in hypertensive patients.

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    Agorasti, Athanasia; Trivellas, Theodoros; Mourvati, Efthimia; Papadopoulos, Vasilios; Tsatalas, Konstantinos; Vargemezis, Vasilios; Passadakis, Ploumis

    2013-06-01

    The aim of this study is to assess whether the haemostatic markers D-dimer, factor VIII (FVIII) and von Willebrand factor (VWF) are predictive of non-dipping status in treated hypertensive patients; so, as easy available laboratory data can predict non-dipping pattern and help with the selection of the patients whom circadian blood pressure should be re-examined. Forty treated hypertensive patients with essential hypertension were included in the study. Twenty-four-hour ambulatory blood pressure monitoring was performed in all patients. Daytime and nocturnal average systolic, diastolic and mean blood pressures were calculated. Patients were characterised as "non-dippers" on the basis of a less than 10 % decline in nocturnal blood pressure (BP); either systolic or diastolic or mean (MAP). D-dimer as marker of fibrinolytic function, FVIII activity and VWF antigen as marker of endothelial dysfunction were measured on plasma. The predictive efficiency was analysed by receiver operating characteristic (ROC) curves. Youden index was used for the estimation of the cut-off points and the associated values for sensitivity and 1-specificity. Plasma levels of D-dimer, FVIII and VWF were significantly higher in non-dippers as compared with dippers, irrespective of the classification used (BP index); all P AUC(ROC) = 0.697, 0.715 and 0.774), FVIII (AUC(ROC) = 0.714, 0.692 and 0.755) and VWF (AUC(ROC) = 0.706, 0.740 and 0.708) in distinguishing non-dipping pattern (systolic, diastolic or mean) in the study population; all P 168 ng/ml (sensitivity/1-specificity for systolic BP non-dippers of 0.789/0.381, for diastolic BP non-dippers 0.923/0.444 and for MAP non-dippers 0.875/0.375). In conclusion, D-dimer has a good predictive value for non-dipping pattern and the decision for the 24-h ambulatory blood pressure re-monitoring among dippers could rely on its values.

  4. Von Willebrand factor regulation of blood vessel formation.

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    Randi, Anna M; Smith, Koval E; Castaman, Giancarlo

    2018-06-04

    Several important physiological processes, from permeability to inflammation to haemostasis, take place at the vessel wall and are regulated by endothelial cells (EC). Thus, proteins that have been identified as regulators of one process are increasingly found to be involved in other vascular functions. Such is the case for Von Willebrand Factor (VWF), a large glycoprotein best known for its critical role in haemostasis. In vitro and in vivo studies have shown that lack of VWF causes enhanced vascularisation, both constitutively and following ischemia. This evidence is supported by studies on blood outgrowth endothelial cells (BOEC) from patients with lack of VWF synthesis (type 3 von Willebrand disease [VWD]). The molecular pathways are likely to involve VWF binding partners, such as integrin αvβ3, and components of Weibel Palade bodies (WPB), such as Angiopoietin-2 and Galectin-3, whose storage is regulated by VWF; these converge on the master regulator of angiogenesis and endothelial homeostasis, vascular endothelial growth factor (VEGF) signalling. Recent studies suggest that the roles of VWF may be tissue-specific. The ability of VWF to regulate angiogenesis has clinical implications for a subset of VWD patients with severe, intractable gastrointestinal bleeding due to vascular malformations. In this article, we review the evidence showing that VWF is involved in blood vessel formation, discuss the role of VWF high molecular weight multimers in regulating angiogenesis, and the value of studies on BOEC in developing a precision medicine approach to validate novel treatments for angiodysplasia in congenital VWD and acquired von Willebrand syndrome. Copyright © 2018 American Society of Hematology.

  5. An ELISA for the quantitation of von Willebrand Factor

    DEFF Research Database (Denmark)

    Vinholt, Pernille Just; Overgaard, Martin; Diederichsen, Axel Cosmus Pyndt

    2013-01-01

    for measurement of von Willebrand factor-osteoprotegerin complex (VWF:OPG) in human plasma. Furthermore, the significance of VWF:OPG complex as a marker of cardiovascular disease (CVD) was evaluated. PATIENTS/METHODS: A sandwich ELISA for quantification of VWF:OPG was developed using a polyclonal rabbit anti...... with and without documented coronary calcification (total n=118). RESULTS AND CONCLUSIONS: The assay detected VWF:OPG complexes in human plasma, while no significant signal was observed when testing solutions containing VWF or recombinant OPG alone. Importantly, the ELISA assay was able to detect in vitro formed...

  6. Evaluation of von Willebrand factor during pregnancy, lactation and oestrous cycle in bitches affected and unaffected by von Willebrand disease.

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    Mattoso, C R S; Takahira, R K; Beier, S L; Araujo, J P; Corrente, J E

    2013-06-01

    Plasmatic concentrations of von Willebrand Factor (vWF) increase during pregnancy in humans and dogs; however the mechanism of such increase is still not well defined. The aims of this study were: (i) to evaluate changes in vWF concentration during pregnancy and during the subsequent oestrous cycle in bitches affected and unaffected by von Willebrand Disease (vWD); (ii) to correlate the vWF levels and cortisol levels in both groups. Seven vWD affected (GI) and nine unaffected (GII) bitches were used. The animals were assessed during pregnancy, parturition, lactation and non-gestational oestrous cycle in 11 moments (Pregnancy 1, Pregnancy 2, Parturition, Lactation 1, Lactation 2, Lactation 3, Anestrus, Proestrus, Oestrus, Diestrus 1, and Diestrus 2). The following tests were performed; measurement of von Willebrand factor antigen (vWF:Ag), albumin and cortisol. In both groups, vWF concentration remained stable during the non-gestational oestrous cycle, but increased during pregnancy, with the highest value observed at parturition. Increases of 70% and 124% in vWF were seen in GI and GII, respectively, compared to anestrus. No correlation was found between vWF and cortisol. Values of vWF:Ag changed during pregnancy, with a peak at parturition, both in vWD affected and unaffected animals. Values of vWF were not altered in the different phases of the oestrous cycle following pregnancy in both groups. Evaluation of vWF during pregnancy can cause false negative results for vWD, but assessment can be performed at any point in the oestrous cycle of non-pregnant bitches. © 2012 Blackwell Verlag GmbH.

  7. Characterization of a novel mutation in the von Willebrand factor propeptide in a distinct subtype of recessive von Willebrand disease

    DEFF Research Database (Denmark)

    Lanke, Elsa; Kristoffersson, Ann-Charlotte; Philips, Malou

    2008-01-01

    von Willebrand factor (VWF) is a plasma protein that consists of a series of multimers of which the high-molecular-weight VWF multimers are the most potent in platelet adhesion and aggregation. The propeptide of the VWF (VWFpp) is known to be essential in the process of multimer assembly. Genetic...... mutation in the VWFpp abolishes multimerization of VWF. The mutation probably disrupts the normal configuration of the VWFpp, which is essential for correct orientation of the protomers and ultimately multimerization. The mutant amino acid is located in a region that is highly conserved across several...

  8. Phenotypic correction of von Willebrand disease type 3 blood-derived endothelial cells with lentiviral vectors expressing von Willebrand factor

    Science.gov (United States)

    De Meyer, Simon F.; Vanhoorelbeke, Karen; Chuah, Marinee K.; Pareyn, Inge; Gillijns, Veerle; Hebbel, Robert P.; Collen, Désiré; Deckmyn, Hans; VandenDriessche, Thierry

    2006-01-01

    Von Willebrand disease (VWD) is an inherited bleeding disorder, caused by quantitative (type 1 and 3) or qualitative (type 2) defects in von Willebrand factor (VWF). Gene therapy is an appealing strategy for treatment of VWD because it is caused by a single gene defect and because VWF is secreted into the circulation, obviating the need for targeting specific organs or tissues. However, development of gene therapy for VWD has been hampered by the considerable length of the VWF cDNA (8.4 kb [kilobase]) and the inherent complexity of the VWF protein that requires extensive posttranslational processing. In this study, a gene-based approach for VWD was developed using lentiviral transduction of blood-outgrowth endothelial cells (BOECs) to express functional VWF. A lentiviral vector encoding complete human VWF was used to transduce BOECs isolated from type 3 VWD dogs resulting in high-transduction efficiencies (95.6% ± 2.2%). Transduced VWD BOECs efficiently expressed functional vector-encoded VWF (4.6 ± 0.4 U/24 hour per 106 cells), with normal binding to GPIbα and collagen and synthesis of a broad range of multimers resulting in phenotypic correction of these cells. These results indicate for the first time that gene therapy of type 3 VWD is feasible and that BOECs are attractive target cells for this purpose. PMID:16478886

  9. [Homocysteine and von Willebrand factor in chronic alcoholism].

    Science.gov (United States)

    Koriakin, A M; Epifantseva, N N; Dadyka, I V; Gorbatovskiĭ, Ia A

    2010-04-01

    The levels of homocysteine (HC) and von Willebrand factor (VWF) as cardiovascular risk factors were studied in patients with Stage II chronic alcoholism. Forty-one men with Stage II chronic alcoholism without clinical signs of somatic and infectious diseases were examined. Their median age was 37 (range 32-40) years; the alcoholization period was 12 (range 8-17) years. Plasma HC and VWF (amount and activity) levels were determined. In 63.4% of chronic alcoholic patients, HC levels was twice as high as in the controls; in 80.6%, both the content and activity of VWF were increased. There was no correlation between the levels of HC and VWF. Vascular endothelial damage concurrent with hyperhomocysteinemia increases a cardiovascular risk in patients with Stage II chronic alcoholism.

  10. Nordic Haemophilia Council's practical guidelines on diagnosis and management of von Willebrand disease

    DEFF Research Database (Denmark)

    Lassila, Riitta; Holme, Pål André; Landorph, Andrea

    2011-01-01

    Von Willebrand disease (VWD) is the most common inherited bleeding disorder characterized by spontaneous or tissue injury-related, mostly mucocutaneous, bleeding events. VWD affects both males and females and is caused by quantitative or qualitative deficiency of Von Willebrand factor. The diagno......Von Willebrand disease (VWD) is the most common inherited bleeding disorder characterized by spontaneous or tissue injury-related, mostly mucocutaneous, bleeding events. VWD affects both males and females and is caused by quantitative or qualitative deficiency of Von Willebrand factor...... subtyping may also be problematic. This article summarizes the guidelines of the Nordic Haemophilia Council (NHC), which are intended to serve as a practical tool and provide the standards for diagnosing and treating VWD patients. The complete Nordic Guidelines on VWD are available at the NHC Web site (http://nordhemophilia.org)....

  11. A study of the effect of ethamsylate (Dicynene) on the bleeding time, von Willebrand factor level and fibrinolysis in patients with von Willebrand's disease.

    Science.gov (United States)

    Hutton, R A; Hales, M; Kernoff, P B

    1988-12-22

    Nine patients with clinically moderate or severe Type I von Willebrand's disease were treated for 2 weeks with ethamsylate (2 g/day in four equal doses) and with a matched placebo in a randomised double-blind trial. Template bleeding time, von Willebrand factor activity (ristocetin co-factor) and antigen, euglobulin lysis time and type I tissue plasminogen activator inhibitor were determined before and at the end of each treatment period. None of these parameters showed any significant change attributable to ethamsylate. Thus, despite the fact that five patients thought subjectively that their bleeding symptoms improved during ethamsylate treatment compared to only one while on placebo, we obtained no evidence that the drug was of benefit to patients with von Willebrand's disease.

  12. Changes in bleeding patterns in von Willebrand disease after institution of long-term replacement therapy : results from the von Willebrand Disease Prophylaxis Network

    NARCIS (Netherlands)

    Holm, Elena; Abshire, Thomas C; Bowen, Joel; Álvarez, M Teresa; Bolton-Maggs, Paula; Carcao, Manuel; Federici, Augusto B; Gill, Joan Cox; Halimeh, Susan; Kempton, Christine; Key, Nigel S; Kouides, Peter; Lail, Alice; Landorph, Andrea; Leebeek, Frank; Makris, Michael; Mannucci, Pier; Mauser-Bunschoten, Eveline P; Nugent, Diane; Valentino, Leonard A; Winikoff, Rochelle; Berntorp, Erik

    Clinically, the leading symptom in von Willebrand disease (VWD) is bleeding, chiefly of mucosal type, for example, epistaxis, gingival, or gastrointestinal bleeding, and menorrhagia. In severe forms of VWD with secondary deficiency of factor VIII, spontaneous joint bleeding, resembling that observed

  13. Association of von Willebrand factor blood levels with exercise hypertension.

    Science.gov (United States)

    Nikolic, Sonja B; Adams, Murray J; Otahal, Petr; Edwards, Lindsay M; Sharman, James E

    2015-05-01

    A hypertensive response to moderate intensity exercise (HRE) is associated with increased cardiovascular risk. The mechanisms of an HRE are unclear, although previous studies suggest this may be due to haemostatic and/or haemodynamic factors. We investigated the relationships between an HRE with haemostatic and hemodynamic indices. Sixty-four participants (57 ± 10 years, 71 % male) with indication for exercise stress testing underwent cardiovascular assessment at rest and during moderate intensity exercise, from which 20 participants developed an HRE (defined as moderate exercise systolic BP ≥ 170 mmHg/men and ≥ 160 mmHg/women). Rest, exercise and post-exercise blood samples were analysed for haemostatic markers, including von Willebrand factor (vWf), and haemodynamic measures of brachial and central blood pressure (BP), aortic stiffness and systemic vascular resistance index (SVRi). HRE participants had higher rest vWf compared with normotensive response to exercise (NRE) participants (1,927 mU/mL, 95 % CI 1,240-2,615, vs. 1,129 mU/mL, 95 % CI 871-1,386; p = 0.016). vWf levels significantly decreased from rest to post-exercise in HRE participants (p = 0.005), whereas vWf levels significantly increased from rest to exercise in NRE participants (p = 0.030). HRE participants also had increased triglycerides, rest BP, aortic stiffness and exercise SVRi (p HRE at moderate intensity.

  14. Differential effects of the loss of intrachain- versus interchain-disulfide bonds in the cystine-knot domain of von Willebrand factor on the clinical phenotype of von Willebrand disease

    NARCIS (Netherlands)

    Tjernberg, Pernilla; Vos, Hans L.; Spaargaren-van Riel, Caroline C.; Luken, Brenda M.; Voorberg, Jan; Bertina, Rogier M.; Eikenboom, Jeroen C. J.

    2006-01-01

    Von Willebrand factor (VWF) contains a large number of cysteine residues, which all form disulfide bonds. Mutations of cysteines located in the cystine-knot (CK) domain of VWF have been identified in both qualitative type 2A (IID) and quantitative type 3 von Willebrand disease (VWD). Our objective

  15. Von Willebrand Factor Gene Variants Associate with Herpes simplex Encephalitis.

    Directory of Open Access Journals (Sweden)

    Nada Abdelmagid

    Full Text Available Herpes simplex encephalitis (HSE is a rare complication of Herpes simplex virus type-1 infection. It results in severe parenchymal damage in the brain. Although viral latency in neurons is very common in the population, it remains unclear why certain individuals develop HSE. Here we explore potential host genetic variants predisposing to HSE. In order to investigate this we used a rat HSE model comparing the HSE susceptible SHR (Spontaneously Hypertensive Rats with the asymptomatic infection of BN (Brown Norway. Notably, both strains have HSV-1 spread to the CNS at four days after infection. A genome wide linkage analysis of 29 infected HXB/BXH RILs (recombinant inbred lines-generated from the prior two strains, displayed variable susceptibility to HSE enabling the definition of a significant QTL (quantitative trait locus named Hse6 towards the end of chromosome 4 (160.89-174Mb containing the Vwf (von Willebrand factor gene. This was the only gene in the QTL with both cis-regulation in the brain and included several non-synonymous SNPs (single nucleotide polymorphism. Intriguingly, in human chromosome 12 several SNPs within the intronic region between exon 43 and 44 of the VWF gene were associated with human HSE pathogenesis. In particular, rs917859 is nominally associated with an odds ratio of 1.5 (95% CI 1.11-2.02; p-value = 0.008 after genotyping in 115 HSE cases and 428 controls. Although there are possibly several genetic and environmental factors involved in development of HSE, our study identifies variants of the VWF gene as candidates for susceptibility in experimental and human HSE.

  16. Von-Willebrand Disease Presenting as Intractable Epistaxis after Nasal Polypectomy

    Directory of Open Access Journals (Sweden)

    Jeong Jin Park

    2014-01-01

    Full Text Available Von-Willebrand disease (VWD is one of the platelet dysfunction disorders that results from a deficiency of Von-Willebrand factor, which is essential for hemostasis. VWD patients typically have normal laboratory results on screening for bleeding disorders. To suspect and diagnose VWD, a careful review of past medical history and laboratory tests is critical. A 59-year-old male patient presented with intractable nasal bleeding after nasal polypectomy. The bleeding was controlled by platelet transfusion, and he was later diagnosed with VWD.

  17. Coats' disease, Turner syndrome, and von Willebrand disease in a patient with Wildtype Norrie disease pseudoglioma.

    Science.gov (United States)

    Desai, Rajen U; Saffra, Norman A; Krishna, Rati P; Rosenberg, Steven E

    2011-01-01

    The authors describe a girl diagnosed as having Coats' disease, Turner syndrome (45X karyotype), and type 1 von Willebrand disease. She tested negative for the Norrie disease pseudoglioma (NDP) gene located on the X-chromosome, which has been suspected of contributing to Coats' disease. Copyright 2010, SLACK Incorporated.

  18. Interference from lupus anticoagulant on von Willebrand factor measurement in splenic marginal zone lymphoma

    DEFF Research Database (Denmark)

    Vinholt, Pernille J; Nybo, Mads

    2015-01-01

    We present a case concerning a patient with splenic marginal zone lymphoma (SMZL) and isolated prolonged activated partial thromboplastin time (aPTT) caused by lupus anticoagulant. Von Willebrand factor (VWF) activity and antigen were immeasurable by latex particle immunoturbidimetric assays...

  19. A systematic review of the effects of hemophilia and von Willebrand disease on arterial trombosis

    NARCIS (Netherlands)

    Biere-Rafi, Sara; Zwiers, M.; Peters, Marjolein; Van Der Meer, Jan; Rosendaal, Frits R; Buller, Harry R; Kamphuisen, Pieter W

    Background: Patients with hemophilia and von Willebrand disease (VWD) may be protected against arterial thrombosis, through a hy-pocoagulable state or atherosclerosis. We performed a systematic review to assess the association between these clotting disorders, arterial thrombosis and the prevalence

  20. Pseudo (Platelet-type von Willebrand disease in pregnancy: a case report

    Directory of Open Access Journals (Sweden)

    Grover Neetu

    2013-01-01

    Full Text Available Abstract Background Pseudo (platelet-type-von Willebrand disease is a rare autosomal dominant bleeding disorder caused by an abnormal function of the glycoprotein lb protein; the receptor for von Willebrand factor. This leads to an increased removal of VWF multimers from the circulation as well as platelets and this results in a bleeding diathesis. Worldwide, less than 50 patients are reported with platelet type von Willebrand disease (PT-VWD. Case presentation We describe the management of platelet type von Willebrand disease in pregnancy of a 26 year old Caucasian primigravida. The initial diagnosis was made earlier following a significant haemorrhage post tonsillectomy several years prior to pregnancy. The patient was managed under a multidisciplinary team which included obstetricians, haematologists, anaesthetists and neonatologists. Care plans were made for the ante- natal, intra-partum and post-partum periods in partnership with the patient. The patient’s platelet count levels dropped significantly during the antenatal period. This necessitated the active exclusion of other causes of thrombocytopenia in pregnancy. A vaginal delivery was desired and plans were made for induction of labour at 38 weeks of gestation with platelet cover in view of the progressive fall of the platelet count. The patient however went into spontaneous labour on the day of induction. She was transfused two units of platelets before delivery. She had an unassisted vaginal delivery of a healthy baby. The successful antenatal counselling has encouraged the diagnosis of the same condition in her mother and sister. We found this to be a particularly interesting case as well as challenging to manage due to its rarity. Psuedo von Willebrand disease in pregnancy can be confused with a number of other differential diagnoses, such as gestational thrombocutopenia, idiopathatic thrombocytopenia, thrombotic thrombocytopenic purpura and pre-eclampsia; all need consideration

  1. Dynamics of von Willebrand factor reactivity in sickle cell disease during vaso-occlusive crisis and steady state

    NARCIS (Netherlands)

    Sins, J. W. R.; Schimmel, M.; Luken, B. M.; Nur, E.; Zeerleder, S. S.; van Tuijn, C. F. J.; Brandjes, D. P. M.; Kopatz, W. F.; Urbanus, R. T.; Meijers, J. C. M.; Biemond, B. J.; Fijnvandraat, K.

    2017-01-01

    Background: Endothelial activation plays a central role in the pathophysiology of vaso-occlusion in sickle cell disease (SCD), facilitating adhesive interactions with circulating blood cells. Upon activation, various adhesive molecules are expressed, including von Willebrand factor (VWF). Increased

  2. Frequency of von willebrand disease in patients of heavy menstrual bleeding

    International Nuclear Information System (INIS)

    Anjum, N.; Shaheen, Z.; Altaf, C.

    2016-01-01

    Objective: To determine the frequency of Von Willebrand disease (vWD) in patients of heavy menstrual bleeding (HMB). Study Design: Hospital based cross sectional study. Place and Duration of Study: Study was conducted at the Gynecology and Obstetrics department, Military Hospital, Rawalpindi in collaboration with Haematology Department of Armed Forces Institute of Pathology (AFIP) Rawalpindi, from Jul to Dec 2015. Material and Methods: Women presenting with HMB were enrolled in the study after informed consent. HMB was defined as cyclical bleeding at normal intervals but patient is using more than 5 pads per day or increase in duration 8/28 or more for at least last 06 months. Venous blood samples were taken and screened for the hemoglobin level (Hb), platelet count, prothrombin time (PT), activated partial thromboplastin time (aPTT) and Von Willebrand antigen (vWF:Ag) in addition to bleeding time (BT) at the Armed Forces Institute of Pathology (AFIP). The demographic details (age, age at menarche), clinical features (menstrual history, quantity of bleeding) and laboratory findings were recorded on the study proforma. Results: A total of 200 patients were enrolled in this study with mean age of 32.3 +- 8.5 years. Mean flow of menstrual blood was 9.8 +- 2.5 pads / day. Mean Hb percent was 8.1 +- 1.4 g/dl. Twenty nine (14.5 percent) patients were having low level of vWF:Ag. Conclusion: There is high frequency of von Willebrand disease among females presenting with heavy menstrual bleeding in our set up. Therefore all patients with heavy menstrual bleeding except those with obvious causes like multiple fibroid should be screened for von Willebrand disease. (author)

  3. Differential proteolytic activation of factor VIII-von Willebrand factor complex by thrombin

    International Nuclear Information System (INIS)

    Hill-Eubanks, D.C.; Parker, C.G.; Lollar, P.

    1989-01-01

    Blood coagulation factor VIII (fVIII) is a plasma protein that is decreased or absent in hemophilia A. It is isolated as a mixture of heterodimers that contain a variably sized heavy chain and a common light chain. Thrombin catalyzes the activation of fVIII in a reaction that is associated with cleavages in both types of chain. The authors isolated a serine protease from Bothrops jararacussu snake venom that catalyzes thrombin-like heavy-chain cleavage but not light-chain cleavage in porcine fVIII as judged by NaDodSO 4 /PAGE and N-terminal sequence analysis. Using a plasma-free assay of the ability of activated 125 I-fVIII to function as a cofactor in the activation of factor X by factor IXa, they found that fVIII is activated by the venom enzyme. The venom enzyme-activated fVIII was isolated in stable form by cation-exchange HPLC. von Willebrand factor inhibited venom enzyme-activated fVIII but not thrombin-activated fVIII. These results suggest that the binding of fVIII to von Willebrand factor depends on the presence of an intact light chain and that activated fVIII must dissociate from von Willebrand factor to exert its cofactor effect. Thus, proteolytic activation of fVIII-von Willebrand factor complex appears to be differentially regulated by light-chain cleavage to dissociate the complex and heavy-chain cleavage to activate the cofactor function

  4. Generation and validation of the Condensed MCMDM-1VWD Bleeding Questionnaire for von Willebrand disease.

    Science.gov (United States)

    Bowman, M; Mundell, G; Grabell, J; Hopman, W M; Rapson, D; Lillicrap, D; James, P

    2008-12-01

    Given the challenges involved in obtaining accurate bleeding histories, attempts at standardization have occurred and the value of quantifying hemorrhagic symptoms has been recognized. An extensive validated bleeding questionnaire (MCMDM-1VWD) was condensed by eliminating all details that did not directly affect the bleeding score (BS) and the correlation between the two versions was tested. Additionally, the diagnostic utility of the condensed version was prospectively tested. Data on 259 individuals who were administered the questionnaire are presented here; 217 being prospectively investigated for von Willebrand disease (VWD) (group 1) and 42 previously known to have type 1, 2 or 3 VWD (group 2). Of the 217 prospectively investigated, 35 had positive BS (> or =4) and 182 had negative scores. Seven individuals (all with positive BS) had laboratory results consistent with type 1 VWD. This results in a sensitivity of 100% and a specificity of 87%. The positive predictive value is 0.20 and the negative predictive value is 1. The correlation between the full MCMDM-1VWD and condensed versions is excellent (Spearman's 0.97, P type 2 > type 1 VWD (anova P < 0.001). There is a strong inverse relationship between VWF:Ag level and BS (Spearman's -0.411, P < 0.001). The Condensed MCMDM-1VWD Bleeding Questionnaire is an efficient, effective tool in the evaluation of patients for VWD.

  5. Clinical and laboratory diagnosis of von Willebrand disease: A synopsis of the 2008 NHLBI/NIH guidelines

    Science.gov (United States)

    Nichols, William L.; Rick, Margaret E.; Ortel, Thomas L.; Montgomery, Robert R.; Sadler, J. Evan; Yawn, Barbara P.; James, Andra H.; Hultin, Mae B.; Manco-Johnson, Marilyn J.; Weinstein, Mark

    2017-01-01

    Von Willebrand factor (VWF) mediates blood platelet adhesion and accumulation at sites of blood vessel injury, and also carries coagulation factor VIII (FVIII) that is important for generating procoagulant activity. Von Willebrand disease (VWD), the most common inherited bleeding disorder, affects males and females, and reflects deficiency or defects of VWF that may also cause decreased FVIII. It may also occur less commonly as an acquired disorder (acquired von Willebrand syndrome). This article briefly summarizes selected features of the March 2008 evidence-based clinical and laboratory diagnostic recommendations from the National Heart, Lung, and Blood Institute (NHLBI) Expert Panel for assessment for VWD or other bleeding disorders or risks. Management of VWD is also addressed in the NHLBI guidelines, but is not summarized here. The VWD guidelines are available at the NHLBI Web site (http://www.nhlbi.nih.gov/guidelines/vwd). PMID:19415721

  6. Single molecule force spectroscopy data and BD- and MD simulations on the blood protein von Willebrand factor

    Directory of Open Access Journals (Sweden)

    Sandra Posch

    2016-09-01

    Full Text Available We here give information for a deeper understanding of single molecule force spectroscopy (SMFS data through the example of the blood protein von Willebrand factor (VWF. It is also shown, how fitting of rupture forces versus loading rate profiles in the molecular dynamics (MD loading-rate range can be used to demonstrate the qualitative agreement between SMFS and MD simulations. The recently developed model by Bullerjahn, Sturm, and Kroy (BSK was used for this demonstration. Further, Brownian dynamics (BD simulations, which can be utilized to estimate the lifetimes of intramolecular VWF interactions under physiological shear, are described. For interpretation and discussion of the methods and data presented here, we would like to directly point the reader to the related research paper, “Mutual A domain interactions in the force sensing protein von Willebrand Factor” (Posch et al., 2016 [1]. Keywords: Atomic force microscopy, Single molecule force spectroscopy, Molecular dynamics simulation, Brownian dynamics simulation, von Willebrand factor

  7. Beneficial Effects of High-Density Lipoproteins on Acquired von Willebrand Syndrome in Aortic Valve Stenosis.

    Science.gov (United States)

    Gebhard, C; Maafi, F; Stähli, B E; Bonnefoy, A; Gebhard, C E; Nachar, W; de Oliveira Moraes, A Benjamim; Mecteau, M; Mihalache-Avram, T; Lavoie, V; Kernaleguen, A E; Shi, Y; Busseuil, D; Chabot-Blanchet, M; Perrault, L P; Rhainds, D; Rhéaume, E; Tardif, J C

    2018-02-01

     Infusions of apolipoprotein A-I (apoA-I), the major protein component of high-density lipoproteins (HDL), result in aortic valve stenosis (AVS) regression in experimental models. Severe AVS can be complicated by acquired von Willebrand syndrome, a haemorrhagic disorder associated with loss of high-molecular-weight von Willebrand factor (vWF) multimers (HMWM), the latter being a consequence of increased shear stress and enhanced vWF-cleaving protease (ADAMTS-13) activity. Although antithrombotic actions of HDL have been described, its effects on ADAMTS-13 and vWF in AVS are unknown.  We assessed ADAMTS-13 activity in plasma derived from a rabbit model of AVS ( n  = 29) as well as in plasma collected from 64 patients with severe AVS (age 65.0 ± 10.4 years, 44 males) undergoing aortic valve replacement (AVR). In both human and rabbit AVS plasma, ADAMTS-13 activity was higher than that in controls ( p  AVS patients had less HMWM than controls (66.3 ± 27.2% vs. 97.2 ± 24.1%, p  AVS rabbits as compared with the placebo group (2.0 ± 0.5 RFU/sec vs. 3.8 ± 0.4 RFU/sec, p  AVS ( r  = -0.3, p  = 0.045).  Our data indicate that HDL levels are associated with reduced ADAMTS-13 activity and increased HMWM. HDL-based therapies may reduce the haematologic abnormalities of the acquired von Willebrand syndrome in AVS. Schattauer GmbH Stuttgart.

  8. Identification and Characterization of Novel Variations in Platelet G-Protein Coupled Receptor (GPCR Genes in Patients Historically Diagnosed with Type 1 von Willebrand Disease.

    Directory of Open Access Journals (Sweden)

    Jacqueline Stockley

    Full Text Available The clinical expression of type 1 von Willebrand disease may be modified by co-inheritance of other mild bleeding diatheses. We previously showed that mutations in the platelet P2Y12 ADP receptor gene (P2RY12 could contribute to the bleeding phenotype in patients with type 1 von Willebrand disease. Here we investigated whether variations in platelet G protein-coupled receptor genes other than P2RY12 also contributed to the bleeding phenotype. Platelet G protein-coupled receptor genes P2RY1, F2R, F2RL3, TBXA2R and PTGIR were sequenced in 146 index cases with type 1 von Willebrand disease and the potential effects of identified single nucleotide variations were assessed using in silico methods and heterologous expression analysis. Seven heterozygous single nucleotide variations were identified in 8 index cases. Two single nucleotide variations were detected in F2R; a novel c.-67G>C transversion which reduced F2R transcriptional activity and a rare c.1063C>T transition predicting a p.L355F substitution which did not interfere with PAR1 expression or signalling. Two synonymous single nucleotide variations were identified in F2RL3 (c.402C>G, p.A134 =; c.1029 G>C p.V343 =, both of which introduced less commonly used codons and were predicted to be deleterious, though neither of them affected PAR4 receptor expression. A third single nucleotide variation in F2RL3 (c.65 C>A; p.T22N was co-inherited with a synonymous single nucleotide variation in TBXA2R (c.6680 C>T, p.S218 =. Expression and signalling of the p.T22N PAR4 variant was similar to wild-type, while the TBXA2R variation introduced a cryptic splice site that was predicted to cause premature termination of protein translation. The enrichment of single nucleotide variations in G protein-coupled receptor genes among type 1 von Willebrand disease patients supports the view of type 1 von Willebrand disease as a polygenic disorder.

  9. Identification and Characterization of Novel Variations in Platelet G-Protein Coupled Receptor (GPCR) Genes in Patients Historically Diagnosed with Type 1 von Willebrand Disease.

    Science.gov (United States)

    Stockley, Jacqueline; Nisar, Shaista P; Leo, Vincenzo C; Sabi, Essa; Cunningham, Margaret R; Eikenboom, Jeroen C; Lethagen, Stefan; Schneppenheim, Reinhard; Goodeve, Anne C; Watson, Steve P; Mundell, Stuart J; Daly, Martina E

    2015-01-01

    The clinical expression of type 1 von Willebrand disease may be modified by co-inheritance of other mild bleeding diatheses. We previously showed that mutations in the platelet P2Y12 ADP receptor gene (P2RY12) could contribute to the bleeding phenotype in patients with type 1 von Willebrand disease. Here we investigated whether variations in platelet G protein-coupled receptor genes other than P2RY12 also contributed to the bleeding phenotype. Platelet G protein-coupled receptor genes P2RY1, F2R, F2RL3, TBXA2R and PTGIR were sequenced in 146 index cases with type 1 von Willebrand disease and the potential effects of identified single nucleotide variations were assessed using in silico methods and heterologous expression analysis. Seven heterozygous single nucleotide variations were identified in 8 index cases. Two single nucleotide variations were detected in F2R; a novel c.-67G>C transversion which reduced F2R transcriptional activity and a rare c.1063C>T transition predicting a p.L355F substitution which did not interfere with PAR1 expression or signalling. Two synonymous single nucleotide variations were identified in F2RL3 (c.402C>G, p.A134 =; c.1029 G>C p.V343 =), both of which introduced less commonly used codons and were predicted to be deleterious, though neither of them affected PAR4 receptor expression. A third single nucleotide variation in F2RL3 (c.65 C>A; p.T22N) was co-inherited with a synonymous single nucleotide variation in TBXA2R (c.6680 C>T, p.S218 =). Expression and signalling of the p.T22N PAR4 variant was similar to wild-type, while the TBXA2R variation introduced a cryptic splice site that was predicted to cause premature termination of protein translation. The enrichment of single nucleotide variations in G protein-coupled receptor genes among type 1 von Willebrand disease patients supports the view of type 1 von Willebrand disease as a polygenic disorder.

  10. Characterization of Zebrafish von Willebrand Factor Reveals Conservation of Domain Structure, Multimerization, and Intracellular Storage

    Directory of Open Access Journals (Sweden)

    Arunima Ghosh

    2012-01-01

    Full Text Available von Willebrand disease (VWD is the most common inherited human bleeding disorder and is caused by quantitative or qualitative defects in von Willebrand factor (VWF. VWF is a secreted glycoprotein that circulates as large multimers. While reduced VWF is associated with bleeding, elevations in overall level or multimer size are implicated in thrombosis. The zebrafish is a powerful genetic model in which the hemostatic system is well conserved with mammals. The ability of this organism to generate thousands of offspring and its optical transparency make it unique and complementary to mammalian models of hemostasis. Previously, partial clones of zebrafish vwf have been identified, and some functional conservation has been demonstrated. In this paper we clone the complete zebrafish vwf cDNA and show that there is conservation of domain structure. Recombinant zebrafish Vwf forms large multimers and pseudo-Weibel-Palade bodies (WPBs in cell culture. Larval expression is in the pharyngeal arches, yolk sac, and intestinal epithelium. These results provide a foundation for continued study of zebrafish Vwf that may further our understanding of the mechanisms of VWD.

  11. Towards personalised therapy for von Willebrand disease: a future role for recombinant products.

    Science.gov (United States)

    Favaloro, Emmanuel J

    2016-05-01

    von Willebrand disease (VWD) is reportedly the most common bleeding disorder and is caused by deficiencies and/or defects in the adhesive plasma protein von Willebrand factor (VWF). Functionally, normal VWF prevents bleeding by promoting both primary and secondary haemostasis. In respect to primary haemostasis, VWF binds to both platelets and sub-endothelial matrix components, especially collagen, to anchor platelets to damaged vascular tissue and promote thrombus formation. VWF also stabilises and protects factor VIII in the circulation, delivering FVIII to the site of injury, which then facilitates secondary haemostasis and fibrin formation/thrombus stabilisation. As a result of this, patients with VWD suffer a bleeding diathesis reflective of a primary defect caused by defective/deficient VWF, which in some patients is compounded by a reduction in FVIII. Management of VWD, therefore, chiefly entails replacement of VWF, and sometimes also FVIII, to protect against bleeding. The current report principally focuses on the future potential for "personalised" management of VWD, given the emerging options in recombinant therapies. Recombinant VWF has been developed and is undergoing clinical trials, and this promising therapy may soon change the way in which VWD is managed. In particular, we can envisage a personalised treatment approach using recombinant VWF, with or without recombinant FVIII, depending on the type of VWD, the extent of deficiencies, and the period and duration of treatment.

  12. Percutaneous coronary intervention and the management of acute coronary syndromes in patients with von Willebrand disease.

    Science.gov (United States)

    Rathore, Sulaiman; Deleon, Dexter; Akram, Hafsa; Sane, David; Ball, Timothy

    2013-04-01

    Von Willebrand disease (vWD) results from quantitative or qualitative deficiency of von Willebrand factor (vWF). The occurrence of myocardial infarction is very rare in patients with vWD. A few case reports of acute coronary syndrome (ACS) in vWD patients are present in the literature, but no definite management recommendations are available for such patients. We report a case of successful percutaneous coronary intervention (PCI) with bare-metal stent (BMS) implantation in a 46-year-old woman with type 1 vWD and history of coronary artery disease (CAD). She received periprocedural dual-antiplatelet therapy for 2 weeks and then continued aspirin without any bleeding complications. The optimal management of patients with vWD and ACS is complex and presents a therapeutic challenge. We propose that dual-antiplatelet therapy can be used safely in most vWD patients presenting with ACS as most of them are type 1 vWD. PCI with BMS can be done safely. Long-term management of these patients requires a systemic approach including hematological consultation, ascertaining vWF levels, as well as patient education and close outpatient follow-up.

  13. Diagnosis and management of von Willebrand disease: a developing country perspective.

    Science.gov (United States)

    Nair, Sukesh Chandran; Viswabandya, Auro; Srivastava, Alok

    2011-07-01

    Special challenges exist in the management of patients with von Willebrand disease (VWD) because of limitations in diagnostic facilities and therapeutic options. However, even within these limitations, it is possible to establish comprehensive services for this condition. Our data show that among 202 patients with VWD, 107 were type 3, 62 were type 1, and the others different categories of type 2. Basic tests such as bleeding time and activated partial thromboplastin time with factor (F)VIII coagulant are able to diagnose most of those with severe disease. We have been able to adapt the specific tests such as von Willebrand factor (VWF) ristocetin cofactor and VWF antigen from the tedious batched manual methods to cost-effective automated methods on advanced coagulometers. Discriminatory tests such as VWF collagen binding, VWF:FVIIIB, ristocetin-induced platelet agglutination (RIPA) are done in batches. Therapeutic options and for the treatment of bleeding include desmopressin, cryoprecipitate, and intermediate purity VWF-containing clotting factor concentrates. Tranexamic acid is also widely used as well as hormonal therapy for menorrhagia. We have also shown that modest doses of intermediate purity FVIII (Koate DVI; Talecris Biotherapeutics, Raleigh, NC, USA) at 35 IU/kg preoperatively and 10 to 20 IU/kg after that are sufficient for surgical hemostasis in these patients. © Thieme Medical Publishers.

  14. Profile of von Willebrand factor antigen and von Willebrand factor propeptide in an overall TIA and ischaemic stroke population and amongst subtypes.

    Science.gov (United States)

    Tobin, W O; Kinsella, J A; Kavanagh, G F; O'Donnell, J S; McGrath, R T; Tierney, S; Egan, B; Feeley, T M; Coughlan, T; Collins, D R; O'Neill, D; Murphy, Sjx; Lim, S J; Murphy, R P; McCabe, Djh

    2017-04-15

    Von Willebrand factor propeptide (VWF:Ag II) is proposed to be a more sensitive marker of acute endothelial activation than von Willebrand factor antigen (VWF:Ag). Simultaneous data on VWF:Ag and VWF:Ag II profiles are very limited following TIA and ischaemic stroke. In this prospective, observational, case-control study, plasma VWF:Ag and VWF:Ag II levels were quantified in 164 patients≤4weeks of TIA or ischaemic stroke (baseline), and then ≥14days (14d) and ≥90days (90d) later, and compared with those from 27 healthy controls. TIA and stroke subtyping was performed according to the TOAST classification. The relationship between VWF:Ag and VWF:Ag II levels and platelet activation status was assessed. 'Unadjusted' VWF:Ag and VWF:Ag II levels were higher in patients at baseline, 14d and 90d than in controls (p≤0.03). VWF:Ag levels remained higher in patients than controls at baseline (p≤0.03), but not at 14d or 90d after controlling for differences in age or hypertension, and were higher in patients at baseline and 90d after controlling for smoking status (p≤0.04). 'Adjusted' VWF:Ag II levels were not higher in patients than controls after controlling for age, hypertension or smoking (p≥0.1). Patients with symptomatic carotid stenosis (N=46) had higher VWF:Ag and VWF:Ag II levels than controls at all time-points (p≤0.002). There was no significant correlation between platelet activation status and VWF:Ag or VWF:Ag II levels. VWF:Ag and VWF:Ag II levels are increased in an overall TIA and ischaemic stroke population, especially in patients with recently symptomatic carotid stenosis. VWF:Ag II was not superior to VWF:Ag at detecting acute endothelial activation in this cohort and might reflect timing of blood sampling in our study. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Dynamics of von Willebrand factor reactivity in sickle cell disease during vaso-occlusive crisis and steady state

    NARCIS (Netherlands)

    Sins, J. W.R.; Schimmel, Marein; Luken, Brenda M.; Nur, Erfan; Zeerleder, S.; van Tuijn, Charlotte F. J.; Brandjes, Dees P. M.; Kopatz, W. F.; Urbanus, R. T.; Meijers, Joost C. M.; Biemond, B. J.; Fijnvandraat, K.

    2017-01-01

    Essentials The role of von Willebrand Factor (VWF) in the pathophysiology of sickle cell disease is unclear. We assessed markers of VWF during admission for vaso-occlusive crisis (VOC) and steady state. VWF reactivity was higher during VOC and was associated with inflammation and neutrophil

  16. Bleeding spectrum in children with moderate or severe von Willebrand disease: Relevance of pediatric-specific bleeding

    NARCIS (Netherlands)

    Sanders, Yvonne V.; Fijnvandraat, Karin; Boender, Johan; Mauser-Bunschoten, Evelien P.; van der Bom, Johanna G.; de Meris, Joke; Smiers, Frans J.; Granzen, Bernd; Brons, Paul; Tamminga, Rienk Y. J.; Cnossen, Marjon H.; Leebeek, Frank W. G.

    2015-01-01

    The bleeding phenotype of children with von Willebrand disease (VWD) needs to be characterized in detail to facilitate diagnosis during childhood and aid in the planning and assessment of treatment strategies. The objective was to evaluate the occurrence, type, and severity of bleeding in a large

  17. Expression of von Willebrand factor and caldesmon in the placental tissues of pregnancies complicated with intrauterine growth restriction.

    Science.gov (United States)

    Göksever Çelik, Hale; Uhri, Mehmet; Yildirim, Gökhan

    2017-11-02

    The decreased placental perfusion is the underlying reason for intrauterine growth restriction that in turn leads to reduced placental perfusion and ischemia. However, there are several issues to be understood in the pathophysiology of intrauterine growth restriction. We aimed to study whether any compensatory response in placental vascular bed occur in pregnancies complicated with intrauterine growth restriction by the immunohistochemical staining of von Willebrand factor and caldesmon in placental tissues. A total of 103 pregnant women was enrolled in the study including 50 patients who were complicated with IUGR and 50 uncomplicated control patients. The study was designed in a prospective manner. All placentas were also stained with von Willebrand factor and caldesmon monoclonal kits. The immunohistochemical staining of von Willebrand factor and caldesmon expressions in placental tissues were different between normal and intrauterine growth restriction group. The percentages of 2+ and 3+ von Willebrand factor expression were higher in the intrauterine growth restriction group comparing with the normal group, although the difference was not statistically significant. The intensity of caldesmon expression was significantly lower in the intrauterine growth restriction group in comparison with the normal group (p intrauterine growth restriction which is a hypoxic condition. But newly formed vessels are immature and not strong enough. Our study is important to clarify the pathophysiology and placental compensatory responses in intrauterine growth restriction.

  18. Joint assessment in von Willebrand disease : Validation of the Haemophilia Joint Health score and Haemophilia Activities List

    NARCIS (Netherlands)

    van Galen, Karin P. M.; Timmer, Merel A.; de Kleijn, Piet; Fischer, Kathelijn; Foppen, Wouter; Schutgens, Roger E. G.; Eikenboom, Jeroen; Meijer, Karina; Cnossen, Marjon H.; Fijnvandraat, Karin; van der Bom, Johanna G.; Laros-van Gorkom, Britta A. P.; Leebeek, Frank W. G.; Mauser-Bunschoten, Eveline P.

    Assessment of clinical outcome after joint bleeding is essential to identify joint damage and optimise treatment, to prevent disability. However, disease-specific tools to assess the musculoskeletal status in patients with von Willebrand disease (VWD) are lacking. We aimed to determine validity and

  19. Functional variation in the arginine vasopressin 2 receptor as a modifier of human plasma von Willebrand factor levels

    DEFF Research Database (Denmark)

    Nossent, Anne Yaël; Robben, J H; Deen, P M T

    2010-01-01

    SUMMARY OBJECTIVES: Stimulation of arginine vasopressin 2 receptor (V2R) with arginine vasopressin (AVP) results in a rise in von Willebrand factor (VWF) and factor VIII plasma levels. We hypothesized that gain-of-function variations in the V2R gene (AVPR2) would lead to higher plasma levels of V...

  20. Performance related factors are the main determinants of the von Willebrand factor response to exhaustive physical exercise

    NARCIS (Netherlands)

    J.E. van Loon (Janine ); M.A.H. Sonneveld (Michelle); S.F.E. Praet (Stephan); M.P.M. de Maat (Moniek); F.W.G. Leebeek (Frank)

    2014-01-01

    textabstractBackground: Physical stress triggers the endothelium to release von Willebrand Factor (VWF) from the Weibel Palade bodies. Since VWF is a risk factor for arterial thrombosis, it is of great interest to discover determinants of VWF response to physical stress. We aimed to determine the

  1. Fluid-phase immunoradiometric assay for the detection of qualitative abnormalities of factor VIII/von Willebrand factor in variants of von Willebrand's disease

    International Nuclear Information System (INIS)

    Girma, J.P.; Ardaillou, N.; Meyer, D.; Lavergne, J.M.; Larrieu, M.J.

    1979-01-01

    Antigenic reactivity of F.VIII/WF in variants of von Willebrand's disease (vWd) was studied with both fluid-phase and solid-phase immunoradiometric assays. Two different (rabbit and goat) 125 I-labeled specific antibodies against purified F.VIII/WF were used in both their divalent (lgG) and their monovalent (Fab fragment) forms. Dose-response curves obtained by reacting a constant amount of antibody with serial dilutions of plasmas from normal or homozygous vWd demonstrated the specificity of the test. The accuracy was significantly higher with 125 I-Fab fragments of goat anti-F.VIII/WF antiserum than intact goat lgG or rabbit lgG or Fab fragments. The significant decrease of the slope of the dose-response curves obtained with plasma from variants of vWd has been interpreted as due to the presence of abnormal F.VIII/WF molecules with decreased antigenic reactivity. A similar anomaly was found in cryosupernatant prepared from normal plasma, paralleling similarities demonstrated between variants of vWd and cryosupernatant. Results of experiments performed by reacting constant plasma dilutions from control or variants of vWd and varying concentrations of anti-F.VIII/WF Fab fragments (rabbit or goat) confirmed the decreased antigenic reactivity of variant F.VIII/WF

  2. Regulation of plasma von Willebrand factor [version 1; referees: 3 approved

    Directory of Open Access Journals (Sweden)

    Karl C Desch

    2018-01-01

    Full Text Available Von Willebrand factor (VWF is a multimeric plasma glycoprotein that plays a central role in the initiation of blood coagulation. Through interactions between its specific functional domains, the vascular wall, coagulation factor VIII, and platelet receptors, VWF maintains hemostasis by binding to platelets and delivering factor VIII to the sites of vascular injury. In the healthy human population, plasma VWF levels vary widely. The important role of VWF is illustrated by individuals at the extremes of the normal distribution of plasma VWF concentrations where individuals with low VWF levels are more likely to present with mucocutaneous bleeding. Conversely, people with high VWF levels are at higher risk for venous thromboembolic disease, stroke, and coronary artery disease. This report will summarize recent advances in our understanding of environmental influences and the genetic control of VWF plasma variation in healthy and symptomatic populations and will also highlight the unanswered questions that are currently driving this field of study.

  3. Technological advances in diagnostic testing for von Willebrand disease: new approaches and challenges.

    Science.gov (United States)

    Hayward, C P M; Moffat, K A; Graf, L

    2014-06-01

    Diagnostic tests for von Willebrand disease (VWD) are important for the assessment of VWD, which is a commonly encountered bleeding disorder worldwide. Technical innovations have been applied to improve the precision and lower limit of detection of von Willebrand factor (VWF) assays, including the ristocetin cofactor activity assay (VWF:RCo) that uses the antibiotic ristocetin to induce plasma VWF binding to glycoprotein (GP) IbIXV on target platelets. VWF-collagen-binding assays, depending on the type of collagen used, can improve the detection of forms of VWD with high molecular weight VWF multimer loss, although the best method is debatable. A number of innovations have been applied to VWF:RCo (which is commonly performed on an aggregometer), including replacing the target platelets with immobilized GPIbα, and quantification by an enzyme-linked immunosorbent assay (ELISA), immunoturbidimetric, or chemiluminescent end-point. Some common polymorphisms in the VWF gene that do not cause bleeding are associated with falsely low VWF activity by ristocetin-dependent methods. To overcome the need for ristocetin, some new VWF activity assays use gain-of-function GPIbα mutants that bind VWF without the need for ristocetin, with an improved precision and lower limit of detection than measuring VWF:RCo by aggregometry. ELISA of VWF binding to mutated GPIbα shows promise as a method to identify gain-of-function defects from type 2B VWD. The performance characteristics of many new VWF activity assays suggest that the detection of VWD, and monitoring of VWD therapy, by clinical laboratories could be improved through adopting newer generation VWF assays. © 2014 John Wiley & Sons Ltd.

  4. Aging and ABO blood type influence von Willebrand factor and factor VIII levels through interrelated mechanisms.

    Science.gov (United States)

    Albánez, S; Ogiwara, K; Michels, A; Hopman, W; Grabell, J; James, P; Lillicrap, D

    2016-05-01

    Essentials von Willebrand factor (VWF) and factor VIII (FVIII) levels are modulated by age and ABO status. The effect of aging and ABO blood type on VWF and FVIII was assessed in 207 normal individuals. Aging and ABO blood type showed combined and bidirectional influences on VWF and FVIII levels. Aging and ABO blood type influence VWF levels through both secretion and clearance mechanisms. Background The effect of aging and ABO blood type on plasma levels of von Willebrand factor (VWF) and factor VIII (FVIII) have been widely reported; however, a comprehensive analysis of their combined effect has not been performed and the mechanisms responsible for the age-related changes have not been determined. Objectives To assess the influence of aging and ABO blood type on VWF and FVIII levels, and to evaluate the contribution of VWF secretion and clearance to the age-related changes. Methods A cross-sectional observational study was performed in a cohort of 207 normal individuals, whose levels of VWF, FVIII, VWF propeptide (VWFpp), VWFpp/VWF:Ag ratio and blood type A antigen content on VWF (A-VWF) were quantified. Results Aging and ABO blood type exerted interrelated effects on VWF and FVIII plasma levels, because the age-related increase in both proteins was significantly higher in type non-O individuals (β = 0.011 vs. 0.005). This increase with age in non-O subjects drove the differences between blood types in VWF levels, as the mean difference increased from 0.13 U/mL in the young to 0.57 U/mL in the old. Moreover, A-VWF was associated with both VWF antigen (β = 0.29; 95% confidence interval [CI], 0.09, 0.50) and VWF clearance (β = -0.15; 95% CI, -0.25, -0.06). We also documented an effect of ABO blood type on VWF secretion with aging, as old individuals with blood type non-O showed higher levels of VWFpp (mean difference 0.29 U/mL). Conclusions Aging and ABO blood type have an interrelated effect on VWF and FVIII levels, where the effect of one is significantly

  5. Hemophilia and von Willebrand's disease: 1. Diagnosis, comprehensive care and assessment. Association of Hemophilia Clinic Directors of Canada.

    Science.gov (United States)

    1995-07-01

    To present current strategies for the assessment and comprehensive care of patients with hemophilia and von Willebrand's disease. Hospital care, home care, single-provider care and multidisciplinary care. Morbidity and quality of life associated with bleeding and treatment. Relevant clinical studies and reports published from 1974 to 1994 were examined. A search was conducted of own reprint files, MEDLINE, citations in the articles reviewed and references provided by colleagues. In the MEDLINE search the following terms were used singly or in combination: "hemophilia," "von Willebrand's disease," "Factor VIII," "Factor IX," "von Willebrand factor," "diagnosis," "management," "home care," "comprehensive care," "inhibitor," "AIDS," "hepatitis," "life expectancy," "complications," "practice guidelines," "consensus statement" and "controlled trial." The in-depth review included only articles written in English from North America and Europe that were relevant to human disease and to a predetermined outline. The availability of treatment products in Canada was also considered. Minimizing morbidity and maximizing functional status and quality of life were given a high value. The optimal use of treatment procedures and home care offers patients the advantages of minimized disability, improved survival and financial benefit. It is also cost effective. Potential harm, including the risk of hepatitis B, hepatitis C and HIV infection, has now been minimized through viral inactivation of plasma-derived coagulation-factor concentrates and through the use of recombinant clotting factor concentrates and other non-plasma-derived hemostatic agents. Patients with hemophilia and severe von Willebrand's disease should be followed in comprehensive care centres that offer expertise in the diagnosis, assessment and management of bleeding and complications and that can meet the educational and counselling needs of patients, family members and health care providers. Eligible patients should

  6. Thalidomide for treatment of gastrointestinal bleedings due to angiodysplasia : a case report in acquired von Willebrand syndrome and review of the literature

    NARCIS (Netherlands)

    Engelen, E T; van Galen, K P M; Schutgens, R E G

    INTRODUCTION: Acquired von Willebrand syndrome is a rare bleeding disorder and treatment of the associated gastrointestinal (GI) bleeding due to angiodysplasia is challenging. AIM: The aim of this study was to present a new case on the successful use of thalidomide in a patient with acquired von

  7. Taq I polymorphism in the 5' region of the von Willebrand Factor (vWF) gene

    Energy Technology Data Exchange (ETDEWEB)

    Lavergne, J M; Bahnak, B R; Assouline, Z; Pietu, G; Kerbiriou-Nabias, D; Meulien, P; Pavirani, A; Meyer, D

    1988-03-25

    pvWFIPC8 is a 2.28 Kb partial cDNA clone for human von Willebrand factor (vWF) isolated from a human lung cDNA library and inserted into the EcoRI site of pUC9. The sequence includes the last 1330 nucleotides that encode for vWF propeptide and 950 nucleotides that encode for mature vWF. Taq I (TCGA) identifies plural invariant bands and two variant bands with alleles at 2.3 (Al) and 1.0 (A2). The frequency was determined in 33 unrelated European and North American caucasians. The extreme 3' region of pvWFIPC8 corresponds to the 5' boundary of an area that could possibly hybridize with similar sequences on human chromosome 22. The 5' 1.74 Kb portion of pvWFIPC8 generated by Bam HI digestion that corresponds to sequences only on chromosome 12 also demonstrates the polymorphism. Co-dominant segregation was demonstrated in 6 families of 48 individuals.

  8. Increased active von Willebrand factor during disease development in the aging diabetic patient population.

    Science.gov (United States)

    Chen, Shuang Feng; Xia, Zuo Li; Han, Ji Ju; Wang, Yi Ting; Wang, Ji Yue; Pan, Shao Dong; Wu, Ya Ping; Zhang, Bin; Li, Guang Yao; Du, Jing Wei; Gao, Hen Qiang; de Groot, Philip G; de Laat, Bas; Hollestelle, Martine J

    2013-02-01

    Type 2 diabetes is known to cause endothelial activation resulting in the secretion of von Willebrand factor (VWF). We have shown that levels of VWF in a glycoprotein Ib-binding conformation are increased in specific clinical settings. The aim of the current study is to investigate whether active VWF levels increase during aging and the development of diabetes within the population of patients suffering from type 2 diabetes. Patients and controls were divided into two groups based on age: older and younger than 60 years of age. VWF antigen, VWF propeptide, VWF activation factor and total active VWF were measured. Patients older than 60 years of age had increased levels of total active VWF, VWF activation factor and VWF propeptide compared to younger patients and controls. All measured VWF parameters were associated with age in diabetic patients. Total active VWF and VWF propeptide correlated with the period of being diagnosed with diabetes. Regression analyses showed that especially the VWF activation factor was strongly associated with diabetes in patients older than 60 years of age. In conclusion, we found that the conformation of VWF could be involved in the disease process of diabetes and that the VWF in a glycoprotein Ib-binding conformation could play a role as risk marker during the development of diabetes in combination with an increase in age. Our study shows that the active quality of VWF was more important than the quantity.

  9. A case of von Willebrand disease discovered during treatment of a sacral pressure ulcer.

    Science.gov (United States)

    Murakami, Masahiro; Fukaya, Sumiko; Furuya, Masaichi; Hyakusoku, Hiko

    2010-12-01

    A sacral pressure ulcer developed in a patient hospitalized for cerebral infarction. Each time necrotic tissue was debrided from the ulcer, pressure hemostasis was necessary to stop the bleeding. As treatment continued, the pressure required to stop the bleeding caused the ulcer to worsen, leading to a downward spiral in the patient's condition. While trying to determine the cause of this problem, we discovered that the patient had von Willebrand disease. Medication controlled the bleeding, and the pressure ulcer began to heal at the same time. It was clear to us that conservative treatment would lead to a complete cure but that the healing process would take a long time and require continued administration of an expensive drug. We decided, therefore, to close the wound with a fasciocutaneous flap so that the patient could be quickly transferred to a rehabilitation hospital. About 1 month after surgery, epithelialization was complete, we were able to discontinue medication, and the patient was discharged. This experience demonstrates the importance of determining the cause of any deviation from the normal course of healing in pressure ulcers. It also indicates that the use of fasciocutaneous flaps, which involve little intraoperative bleeding in short surgeries, is appropriate in cases like this one.

  10. Successful Ultrasound-Guided Femoral Nerve Blockade and Catheterization in a Patient with Von Willebrand Disease

    Directory of Open Access Journals (Sweden)

    Youmna E. DiStefano

    2015-01-01

    Full Text Available Peripheral nerve blockade (PNB is superior to neuraxial anesthesia and/or opioid therapy for perioperative analgesia in total knee replacement (TKR. Evidence on the safety of PNB in patients with coagulopathy is lacking. We describe the first documented account of continuous femoral PNB for perioperative analgesia in a patient with Von Willebrand Disease (vWD. Given her history of opioid tolerance and after an informative discussion, a continuous femoral PNB was planned for in this 34-year-old female undergoing TKR. A Humate-P intravenous infusion was started and the patient was positioned supinely. Using sterile technique with ultrasound guidance, a Contiplex 18 Gauge Tuohy needle was advanced in plane through the fascia iliaca towards the femoral nerve. A nerve catheter was threaded through the needle and secured without complications. Postoperatively, a levobupivacaine femoral catheter infusion was maintained, and twice daily Humate-P intravenous infusions were administered for 48 hours; enoxaparin thromboprophylaxis was initiated thereafter. The patient was discharged uneventfully on postoperative day 4. Given documentation of delayed, unheralded bleeding from PNB in coagulopathic patients, we recommend individualized PNB in vWD patients. Multidisciplinary team involvement is required to guide factor supplementation and thromboprophylaxis, as is close follow-up to elicit signs of bleeding throughout the delayed postoperative period.

  11. Von Willebrand Factor as a Novel Player in Valvular Heart Disease: From Bench to Valve Replacement.

    Science.gov (United States)

    Gragnano, Felice; Crisci, Mario; Bigazzi, Maurizio Cappelli; Bianchi, Renatomaria; Sperlongano, Simona; Natale, Francesco; Fimiani, Fabio; Concilio, Claudia; Cesaro, Arturo; Pariggiano, Ivana; Diana, Vincenzo; Limongelli, Giuseppe; Cirillo, Plinio; Russo, Mariagiovanna; Golia, Enrica; Calabrò, Paolo

    2018-02-01

    von Willebrand Factor (vWF) is a well-known mediator of hemostasis and vascular inflammation. Its dynamic modulation in the bloodstream, according to hemodynamic conditions, makes it an appealing biomarker in patients with valvular heart disease (VHD). Recent studies highlight the close connection between vWF and VHD, with possible implications in the pathogenesis of VHD, promoting valve aging and calcification or favoring the development of infective endocarditis. Moreover, vWF has been recently proposed as a new diagnostic and prognostic tool in patients with valve stenosis or regurgitation, showing a strict correlation with severity of valve disease, outcome, and bleeding (Heyde syndrome). A novel role for vWF is also emerging in patients undergoing percutaneous or surgical valve repair/replacement to select and stratify patients, evaluate periprocedural bleeding risk, and detect procedural complications. We also report our single-center experience, suggesting, for the first time, possible clinical implications for vWF in percutaneous mitral valve repair (MitraClip). This review summarizes recent advances in the role of vWF in VHD with an updated overview going from bench to operating room.

  12. Pattern of von Willebrand factor in hypertensive patients in Lagos, Nigeria

    Directory of Open Access Journals (Sweden)

    Ann Abiola Ogbenna

    2018-01-01

    Full Text Available Background and Objective: Hypertension alone accounts for 50% of death from stroke. Its ability to induce endothelial dysfunction leads to the release of von Willebrand factor (vWF, a prothrombotic glycoprotein. The increase secretion of vWF may account for increased risk of stroke in hypertensive disorders. This study aimed to determine the vWF:antigen (Ag levels among hypertensives and assess its relationship with blood pressure and occurrence of stroke in hypertensives. Subjects and Methods: The study included 66 hypertensives, 33 with stroke (HS and 33 without stroke (HWS, and 33 controls matched for age and sex. Structured questionnaires were used to obtain biodata and clinical information. Blood pressure was taken after 15 min rest. Four milliliters of blood was collected into 0.1 ml of 3.2% trisodium citrate for vWF:Ag assay and 4 ml into K-ethylenediaminetetraacetic acid anticoagulant bottles for blood grouping and erythrocyte sedimentation rate. Data were analyzed with SPSS version 21. Confidence interval was set at 95%. Results: Mean vWF:Ag levels were significantly higher in hypertensives compared with nonhypertensives (P = 0.005, but no statistically significant difference was observed between HS and HWS (P = 0.874. A positive correlation of vWF with systolic blood pressure was observed (r = 0.335, P = 0.001. Conclusion: Our study suggests that higher systolic blood pressure is associated with higher levels of endothelial activation and release of vWF.

  13. Thrombomodulin and von Willebrand factor as markers of radiation-induced endothelial injury

    International Nuclear Information System (INIS)

    Zhou Quansheng; Zhao Yimin; Li Peixia; Bai Xia; Ruan Changgeng

    1992-02-01

    Cultured confluent human umbilical vein endothelial cells were irradiated in vitro by 60 Co-gamma ray at doses from 0 to 50 Gy. After irradiation Thrombomodulin in the supernatants of endothelial cell culture medium, on the surface of the cells and within the cells was measured at different times over six days. At twenty-four hours after irradiation, an increase in the release of Thrombomodulin and von Willebrand factor from irradiated endothelial cells and an increase in the number of molecules and the activity of Thrombomodulin on the surface of the cells were observed, which were radiation-dose dependent. The capacity of the cells to produce and release Thrombomodulin was decreased from two to six days after exposure to 60 Co-gamma ray. Our data indicate that radiation can injure endothelial cells and that Thrombomodulin may be as a marker of radiation-induced endothelial cell injury. The relationship between dysfunction of irradiated endothelial cells and the pathological mechanisms of acute radiation sickness are discussed

  14. The structure of the TFIIH p34 subunit reveals a von Willebrand factor A like fold.

    Directory of Open Access Journals (Sweden)

    Dominik R Schmitt

    Full Text Available RNA polymerase II dependent transcription and nucleotide excision repair are mediated by a multifaceted interplay of subunits within the general transcription factor II H (TFIIH. A better understanding of the molecular structure of TFIIH is the key to unravel the mechanism of action of this versatile protein complex within these vital cellular processes. The importance of this complex becomes further evident in the context of severe diseases like xeroderma pigmentosum, Cockayne's syndrome and trichothiodystrophy, that arise from single point mutations in TFIIH subunits. Here we describe the structure of the p34 subunit of the TFIIH complex from the eukaryotic thermophilic fungus Chaetomium thermophilum. The structure revealed that p34 contains a von Willebrand Factor A (vWA like domain, a fold which is generally known to be involved in protein-protein interactions. Within TFIIH p34 strongly interacts with p44, a positive regulator of the helicase XPD. Putative protein-protein interfaces are analyzed and possible binding sites for the p34-p44 interaction suggested.

  15. Neuropeptide delivery to the brain: a von Willebrand factor signal peptide to direct neuropeptide secretion

    Directory of Open Access Journals (Sweden)

    de Backer Marijke WA

    2010-08-01

    Full Text Available Abstract Background Multiple neuropeptides, sometimes with opposing functions, can be produced from one precursor gene. To study the roles of the different neuropeptides encoded by one large precursor we developed a method to overexpress minigenes and establish local secretion. Results We fused the signal peptide from the Von Willebrand Factor (VWF to a furin site followed by a processed form of the Agouti related protein (AgRP, AgRP83-132 or α-melanocyte stimulating hormone. In vitro, these minigenes were secreted and biologically active. Additionally, the proteins of the minigenes were not transported into projections of primary neurons, thereby ensuring local release. In vivo administration of VWF-AgRP83-132 , using an adeno-associated viral vector as a delivery vehicle, into the paraventricular hypothalamus increased body weight and food intake of these rats compared to rats which received a control vector. Conclusions This study demonstrated that removal of the N-terminal part of full length AgRP and addition of a VWF signal peptide is a successful strategy to deliver neuropeptide minigenes to the brain and establish local neuropeptide secretion.

  16. PROTEOLYTIC PROCESSING OF VON WILLEBRAND FACTOR BY ADAMTS13 AND LEUKOCYTE PROTEASES

    Directory of Open Access Journals (Sweden)

    Stefano Lancellotti

    2013-09-01

    Full Text Available ADAMTS13 is a 190 kDa zinc protease encoded by a gene located on chromosome 9q34.   This protease specifically hydrolyzes von Willebrand factor (VWF multimers, thus causing VWF size reduction. ADAMTS13 belongs to the A Disintegrin And Metalloprotease with ThromboSpondin type 1 repeats (ADAMTS family, involved in proteolytic processing of many matrix proteins. ADAMTS13 consists of numerous domains including a metalloprotease domain, a disintegrin domain, several thrombospondin type 1 (TSP1 repeats, a cysteine-rich domain, a spacer domain and 2 CUB (Complement c1r/c1s, sea Urchin epidermal growth factor, and Bone morphogenetic protein domains. ADAMTS13 cleaves a single peptide bond (Tyr1605-Met1606 in the central A2 domain of the VWF molecule. This proteolytic cleavage is essential to reduce the size of ultra-large VWF polymers, which, when exposed to high shear stress in the microcirculation, are prone to form with platelets clumps, which cause severe syndromes called thrombotic microangiopathies (TMAs. In this review, we a discuss the current knowledge of structure-function aspects of ADAMTS13 and its involvement in the pathogenesis of TMAs, b address the recent findings concerning proteolytic processing of VWF multimers by different proteases, such as the leukocyte-derived serine and metallo-proteases and c indicate the direction of future investigations

  17. von Willebrand factor as a novel noninvasive predictor of portal hypertension and esophageal varices in hepatitis B patients with cirrhosis.

    Science.gov (United States)

    Wu, Hao; Yan, Shiping; Wang, Guangchuan; Cui, Shaobo; Zhang, Chunqing; Zhu, Qiang

    2015-01-01

    At present, there is no perfect noninvasive method to assess portal hypertension and esophageal varices. Early predicting esophageal varices can provide evidence for managing cirrhotic patients. We aimed to further investigate von Willebrand factor (vWF) as a noninvasive predictor of portal hypertension, especially of esophageal varices. A total of 60 hepatitis B patients with cirrhosis and 45 healthy subjects were enrolled in this study. Levels of six markers were examined. All patients underwent hepatic venous pressure gradient (HVPG) and esophagogastroduodenoscopy. We evaluated the performance of six factors for diagnosis of portal hypertension and esophageal varices. The vWF levels in liver tissues were observed by immunohistochemistry. Correlations between the level of vWF in liver tissues and HVPG and between levels of vWF in tissues and plasma were examined. Cutoff values of plasma vWF (1510.5 mU/mL and 1701 mU/mL) showed high positive predictive value (PPV, 90.2% and 87.5%) in predicting clinically significant portal hypertension and severe portal hypertension. Cutoff values of vWF (1414 mU/ml and 1990 mU/mL, PPV 90.3% and 86.3%, respectively) were provided to detect the presence and degree of esophageal varices. Linear correlations were observed between levels of vWF in liver tissues and HVPG (r(2) = 0.552, p portal hypertension and esophageal varices in hepatitis B patients with cirrhosis. Increased levels of vWF in liver tissues may induce the elevated plasma vWF levels, but molecular mechanism is needed for further study.

  18. Unconjugated Bilirubin Inhibits Proteolytic Cleavage of von Willebrand Factor by ADAMTS13 Protease

    Science.gov (United States)

    Lu, Rui-Nan; Yang, Shangbin; Wu, Haifeng M.; Zheng, X. Long

    2015-01-01

    Summary Background Bilirubin is a yellow breakdown product of heme catabolism. Increased serum levels of unconjugated bilirubin are conditions commonly seen in premature neonates and adults with acute hemolysis including thrombotic microangiopathy. Previous studies have shown that unconjugated bilirubin lowers plasma ADAMTS13 activity, but the mechanism is not fully understood. Objectives The study is to determine whether unconjugated bilirubin directly inhibits the cleavage of von Willebrand factor (VWF) and its analogs by ADAMTS13. Methods Fluorogenic, SELDI-TOF mass spectrometric assay, and Western blotting analyses were employed to address this question. Results Unconjugated bilirubin inhibits the cleavage of F485-rVWF73-H, D633-rVWF73-H, and GST-rVWF71-11K by ADAMTS13 in a concentration-dependent manner with a half-maximal inhibitory concentration (IC50) of ~13 μM, ~70 μM, and ~17 μM, respectively. Unconjugated bilirubin also dose-dependently inhibits the cleavage of multimeric VWF by ADAMTS13 under denaturing conditions. The inhibitory activity of bilirubin on the cleavage of D633-rVWF73-H and multimeric VWF, but not F485-rVWF73-H, was eliminated after incubation with bilirubin oxidase that converts bilirubin to biliverdin. Furthermore, plasma ADAMTS13 activity in patients with hyperbilirubinemia is lower prior to than after treatment with bilirubin oxidase. Conclusions unconjugated bilirubin directly inhibits ADAMTS13’s ability to cleave both peptidyl and native VWF substrates in addition to its interference with certain fluorogenic assays. Our findings may help proper interpretation of ADAMTS13 results under pathological conditions. Whether elevated serum unconjugated bilirubin has an adverse effect in vivo remains to be determined in our future study. PMID:25782102

  19. Increased metastatic potential of tumor cells in von Willebrand factor-deficient mice.

    Science.gov (United States)

    Terraube, V; Pendu, R; Baruch, D; Gebbink, M F B G; Meyer, D; Lenting, P J; Denis, C V

    2006-03-01

    The key role played by von Willebrand factor (VWF) in platelet adhesion suggests a potential implication in various pathologies, where this process is involved. In cancer metastasis development, tumor cells interact with platelets and the vessel wall to extravasate from the circulation. As a potential mediator of platelet-tumor cell interactions, VWF could influence this early step of tumor spread and therefore play a role in cancer metastasis. To investigate whether VWF is involved in metastasis development. In a first step, we characterized the interaction between murine melanoma cells B16-BL6 and VWF in vitro. In a second step, an experimental metastasis model was used to compare the formation of pulmonary metastatic foci in C57BL/6 wild-type and VWF-null mice following the injection of B16-BL6 cells or Lewis lung carcinoma cells. In vitro adhesion assays revealed that VWF is able to promote a dose-dependent adhesion of B16-BL6 cells via its Arg-Gly-Asp (RGD) sequence. In the experimental metastasis model, we found a significant increase in the number of pulmonary metastatic foci in VWF-null mice compared with the wild-type mice, a phenotype that could be corrected by restoring VWF plasma levels. We also showed that increased survival of the tumor cells in the lungs during the first 24 h in the absence of VWF was the cause of this increased metastasis. These findings suggest that VWF plays a protective role against tumor cell dissemination in vivo. Underlying mechanisms remain to be investigated.

  20. Plasmatic ADAMTS-13 metalloprotease and von Willebrand factor in children with cyanotic congenital heart disease

    Energy Technology Data Exchange (ETDEWEB)

    Soares, R.P.S. [Fundação Pró-Sangue Hemocentro de São Paulo, São Paulo, SP (Brazil); Bydlowski, S.P.; Nascimento, N.M. [Laboratório de Investigação Médica-31, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP (Brazil); Thomaz, A.M.; Bastos, E.N.M.; Lopes, A.A. [Faculdade de Medicina, Instituto do Coração, Universidade de São Paulo, São Paulo, SP (Brazil)

    2013-04-05

    Changes in plasma von Willebrand factor concentration (VWF:Ag) and ADAMTS-13 activity (the metalloprotease that cleaves VWF physiologically) have been reported in several cardiovascular disorders with prognostic implications. We therefore determined the level of these proteins in the plasma of children with cyanotic congenital heart disease (CCHD) undergoing surgical treatment. Forty-eight children were enrolled (age 0.83 to 7.58 years). Measurements were performed at baseline and 48 h after surgery. ELISA, collagen-binding assays and Western blotting were used to estimate antigenic and biological activities, and proteolysis of VWF multimers. Preoperatively, VWF:Ag and ADAMTS-13 activity were decreased (65 and 71% of normal levels considered as 113 (105-129) U/dL and 91 ± 24% respectively, P < 0.003) and correlated (r = 0.39, P = 0.0064). High molecular weight VWF multimers were not related, suggesting an interaction of VWF with cell membranes, followed by proteolytic cleavage. A low preoperative ADAMTS-13 activity, a longer activated partial thromboplastin time and the need for cardiopulmonary bypass correlated with postoperative bleeding (P < 0.05). Postoperatively, ADAMTS-13 activity increased but less extensively than VWF:Ag (respectively, 2.23 and 2.83 times baseline, P < 0.0001), resulting in an increased VWF:Ag/ADAMTS-13 activity ratio (1.20 to 1.54, respectively, pre- and postoperative median values, P = 0.0029). ADAMTS-13 consumption was further confirmed by decreased ADAMTS-13 antigenic concentration (0.91 ± 0.30 to 0.70 ± 0.25 µg/mL, P < 0.0001) and persistent proteolysis of VWF multimers. We conclude that, in pediatric CCHD, changes in circulating ADAMTS-13 suggest enzyme consumption, associated with abnormal structure and function of VWF.

  1. Multiple functions of the von Willebrand Factor A domain in matrilins: secretion, assembly, and proteolysis

    Directory of Open Access Journals (Sweden)

    Kanbe Katsuaki

    2008-06-01

    Full Text Available Abstract The von Willebrand Factor A (vWF A domain is one of the most widely distributed structural modules in cell-matrix adhesive molecules such as intergrins and extracellular matrix proteins. Mutations in the vWF A domain of matrilin-3 cause multiple epiphyseal dysplasia (MED, however the pathological mechanism remains to be determined. Previously we showed that the vWF A domain in matrilin-1 mediates formation of a filamentous matrix network through metal-ion dependent adhesion sites in the domain. Here we show two new functions of the vWF A domain in cartilage-specific matrilins (1 and 3. First, vWF A domain regulates oligomerization of matrilins. Insertion of a vWF A domain into matrilin-3 converts the formation of a mixture of matrilin-3 tetramer, trimer, and dimer into a tetramer only, while deletion of a vWF A domain from matrilin-1 converts the formation of the native matrilin-1 trimer into a mixture of trimer and dimer. Second, the vWF A domain protects matrilin-1 from proteolysis. We identified a latent proteolytic site next to the vWF A2 domain in matrilin-1, which is sensitive to the inhibitors of matrix proteases. Deletion of the abutting vWF A domain results in degradation of matrilin-1, presumably by exposing the adjacent proteolytic site. In addition, we also confirmed the vWF A domain is vital for the secretion of matrilin-3. Secretion of the mutant matrilin-3 harbouring a point mutation within the vWF A domain, as occurred in MED patients, is markedly reduced and delayed, resulting from intracellular retention of the mutant matrilin-3. Taken together, our data suggest that different mutations/deletions of the vWF A domain in matrilins may lead to distinct pathological mechanisms due to the multiple functions of the vWF A domain.

  2. Complex changes in von Willebrand factor-associated parameters are acquired during uncomplicated pregnancy.

    Directory of Open Access Journals (Sweden)

    Danielle N Drury-Stewart

    Full Text Available The coagulation protein von Willebrand Factor (VWF is known to be elevated in pregnancy. However, the timing and nature of changes in VWF and associated parameters throughout pregnancy are not well understood.To better understand the changes in VWF provoked by pregnancy, we studied VWF-associated parameters in samples collected over the course of healthy pregnancies.We measured VWF antigen (VWF:Ag, VWF propeptide (VWFpp, Factor VIII (FVIII, and ADAMTS13 activity in samples collected from 46 women during pregnancy and at non-pregnant baseline. We also characterized pregnant vs. non-pregnant VWF multimer structure in 21 pregnancies, and performed isoelectric focusing (IEF of VWF in two pregnancies which had samples from multiple trimesters.VWF:Ag and FVIII levels were significantly increased during pregnancy. ADAMTS13 activity was unchanged. VWFpp levels increased much later in pregnancy than VWF:Ag, resulting in a progressive decrease in VWFpp:Ag ratios. FVIII:VWF ratios also decreased in pregnancy. Most pregnancies exhibited a clear loss of larger VWF multimers and altered VWF triplet structure. Further evidence of acquired VWF qualitative changes in pregnancy was found in progressive, reversible shifts in VWF IEF patterns over gestation.These data support a new view of pregnancy in which VWF can acquire qualitative changes associated with advancing gestational age. Modeling supports a scenario in which both increased VWF production and doubling of the VWF half-life would account for the data observed. We propose that gestation induces a prolongation in VWF survival, which likely contributes to increased total VWF levels and altered VWF structure.

  3. Comparative analysis of von Willebrand factor profiles after implantation of left ventricular assist device and total artificial heart.

    Science.gov (United States)

    Reich, H J; Morgan, J; Arabia, F; Czer, L; Moriguchi, J; Ramzy, D; Esmailian, F; Lam, L; Dunhill, J; Volod, O

    2017-08-01

    Essentials Bleeding is a major source of morbidity during mechanical circulatory support. von Willebrand factor (VWF) multimer loss may contribute to bleeding. Different patterns of VWF multimer loss were seen with the two device types. This is the first report of total artificial heart associated VWF multimer loss. Background Bleeding remains a challenge during mechanical circulatory support and underlying mechanisms are incompletely understood. Functional von Willebrand factor (VWF) impairment because of loss of high-molecular-weight multimers (MWMs) produces acquired von Willebrand disease (VWD) after left ventricular assist device (LVAD). Little is known about VWF multimers with total artificial hearts (TAHs). Here, VWF profiles with LVADs and TAHs are compared using a VWD panel. Methods VWD evaluations for patients with LVAD or TAH (2013-14) were retrospectively analyzed and included: VWF activity (ristocetin cofactor, VWF:RCo), VWF antigen (VWF:Ag), ratio of VWF:RCo to VWF:Ag, and quantitative VWF multimeric analysis. Results Twelve patients with LVADs and 12 with TAHs underwent VWD evaluation. All had either normal (47.8%) or elevated (52.2%) VWF:RCo, normal (26.1%) or elevated (73.9%) VWF:Ag and 50.0% were disproportional (ratio ≤ 0.7). Multimeric analysis showed abnormal patterns in all patients with LVADs: seven with high MWM loss; five with highest MWM loss. With TAH, 10/12 patients had abnormal patterns: all with highest MWM loss. High MWM loss correlated with presence of LVAD and highest MWM loss with TAH. Increased low MWMs were detected in 22/24. Conclusion Using VWF multimeric analysis, abnormalities after LVAD or TAH were detected that would be missed with measurements of VWF level alone: loss of high MWM predominantly in LVAD, loss of highest MWM in TAH, and elevated levels of low MWM in both. This is the first study to describe TAH-associated highest MWM loss, which may contribute to bleeding. © 2017 International Society on Thrombosis and

  4. Exercise-induced shear stress is associated with changes in plasma von Willebrand factor in older humans

    OpenAIRE

    Gonzales, Joaquin U.; Thistlethwaite, John R.; Thompson, Benjamin C.; Scheuermann, Barry W.

    2009-01-01

    Shear stress is the frictional force of blood against the endothelium, a stimulus for endothelial activation and the release of von Willebrand factor (vWF). This study tested the hypothesis that the increase in shear stress associated with exercise correlates with plasma vWF. Young (n = 14, 25.7 ± 5.4 y) and older (n = 13, 65.6 ± 10.7 y) individuals participated in 30 min of dynamic handgrip exercise at a moderate intensity. Brachial artery diameter and blood flow were measured using ultrasou...

  5. Cesariana em paciente com doença de von Willebrand associada à infecção pelo HIV: relato de caso Cesárea en paciente con enfermedad de von Willebrand asociada a la infección por el HIV: relato de caso Anesthesia for cesarean section in patient with von Willebrand's disease and HIV infection: case report

    Directory of Open Access Journals (Sweden)

    Vanessa Rezende Balle

    2004-12-01

    Full Text Available JUSTIFICATIVA E OBJETIVOS: A doença de von Willebrand é a alteração inata da coagulação mais freqüente em mulheres jovens. A infecção por HIV tem mostrado incidência progressivamente maior em mulheres, constatando-se transmissão vertical em até 25% dos casos. O objetivo deste relato é mostrar o caso de uma paciente com doença de von Willebrand e HIV positivo submetida à cesariana. RELATO DO CASO: Paciente de 24 anos, portadora de anemia microcítica, doença de von Willebrand e HIV, chegou à emergência obstétrica em início de trabalho de parto. Não realizou pré-natal. Foi indicada cesariana a fim de diminuir os riscos de transmissão vertical em paciente com carga viral de HIV desconhecida. Apresentava hematomas pelo corpo e história de hematoma de parede abdominal em cesariana anterior. Os testes de coagulação eram pouco alterados. Após infusão de concentrado de fator VIII foi realizada anestesia geral. Mãe e recém-nascido apresentaram evolução satisfatória. CONCLUSÕES: A avaliação de manifestações clínicas em pacientes com coagulopatia é fundamental na decisão do tipo de anestesia a ser indicada para cada paciente. A avaliação deve ser individualizada, considerando os riscos e benefícios da técnica escolhida. Nestas pacientes, deve-se sempre restringir ao máximo a indicação de interrupção da gestação por via alta, optando-se sempre pelos métodos menos invasivos. A terapia com concentrado de fator VIII é atualmente a melhor opção de tratamento, corrigindo a deficiência específica e diminuindo os riscos de transmissão viral.JUSTIFICATIVA Y OBJETIVOS: La enfermedad de von Willebrand es la alteración innata de la coagulación más frecuente en mujeres jóvenes. La infección por HIV ha mostrado incidencia progresivamente mayor en mujeres, constatandose transmisión vertical en hasta 25% de los casos. El objetivo de este relato es mostrar el caso de una paciente con Enfermedad de von

  6. Dogs with hearth diseases causing turbulent high-velocity blood flow have changes in patelet function and von Willebrand factor multimer distribution

    DEFF Research Database (Denmark)

    Tarnow, Inge; Kristensen, Annemarie Thuri; Olsen, Lisbeth Høier

    2005-01-01

    The purpose of this prospective study was to investigate platelet function using in vitro tests based on both high and low shear rates and von Willebrand factor (vWf) multimeric composition in dogs with cardiac disease and turbulent high-velocity blood flow. Client-owned asymptomatic, untreated d...

  7. The impact of statin therapy on plasma levels of von Willebrand factor antigen. Systematic review and meta-analysis of randomised placebo-controlled trials

    NARCIS (Netherlands)

    Sahebkar, Amirhossein; Serban, Corina; Ursoniu, Sorin; Mikhailidis, Dimitri P.; Undas, Anetta; Lip, Gregory Y. H.; Bittner, Vera; Ray, Kausik; Watts, Gerald F.; Hovingh, G. Kees; Rysz, Jacek; Kastelein, John J. P.; Banach, Maciej

    2016-01-01

    Increased plasma levels of von Willebrand factor antigen (vWF:Ag) are associated with high risk of coronary artery disease. The effect of statin therapy on vWF:Ag levels remains uncertain. Therefore the aim of this meta-analysis was to evaluate the effect of statin therapy on vWF:Ag Levels. A

  8. Binding of von Willebrand factor to collagen type III: role of specific amino acids in the collagen binding domain of vWF and effects of neighboring domains

    NARCIS (Netherlands)

    van der Plas, R. M.; Gomes, L.; Marquart, J. A.; Vink, T.; Meijers, J. C.; de Groot, P. G.; Sixma, J. J.; Huizinga, E. G.

    2000-01-01

    Binding of von Willebrand Factor (vWF) to sites of vascular injury is the first step of hemostasis. Collagen types I and III are important binding sites for vWF. We have previously determined the three-dimensional structure of the collagen binding A3 domain of vWF (Huizinga et al., Structure 1997;

  9. Insulin resistance is accompanied by increased von Willebrand factor levels in nondiabetic women: a study of offspring of type 2 diabetic subjects compared to offspring of nondiabetic subjects

    DEFF Research Database (Denmark)

    Foss, Anne-Catherine; Vestbo, Else; Frøland, Anders

    2002-01-01

    OBJECTIVES: To examine whether levels of von Willebrand factor (vWF), fibrinogen and fibronectin are related to a parental history of type 2 diabetes and to determine possible explanatory factors for high versus low vWF and fibrinogen. DESIGN: Cross-sectional study. SUBJECTS, MAIN OUTCOME MEASURE...

  10. Molecular and clinical profile of von Willebrand disease in Spain (PCM-EVW-ES): comprehensive genetic analysis by next-generation sequencing of 480 patients.

    Science.gov (United States)

    Borràs, Nina; Batlle, Javier; Pérez-Rodríguez, Almudena; López-Fernández, María Fernanda; Rodríguez-Trillo, Ángela; Lourés, Esther; Cid, Ana Rosa; Bonanad, Santiago; Cabrera, Noelia; Moret, Andrés; Parra, Rafael; Mingot-Castellano, María Eva; Balda, Ignacia; Altisent, Carme; Pérez-Montes, Rocío; Fisac, Rosa María; Iruín, Gemma; Herrero, Sonia; Soto, Inmaculada; de Rueda, Beatriz; Jiménez-Yuste, Víctor; Alonso, Nieves; Vilariño, Dolores; Arija, Olga; Campos, Rosa; Paloma, María José; Bermejo, Nuria; Berrueco, Rubén; Mateo, José; Arribalzaga, Karmele; Marco, Pascual; Palomo, Ángeles; Sarmiento, Lizheidy; Iñigo, Belén; Nieto, María Del Mar; Vidal, Rosa; Martínez, María Paz; Aguinaco, Reyes; César, Jesús María; Ferreiro, María; García-Frade, Javier; Rodríguez-Huerta, Ana María; Cuesta, Jorge; Rodríguez-González, Ramón; García-Candel, Faustino; Cornudella, Rosa; Aguilar, Carlos; Vidal, Francisco; Corrales, Irene

    2017-12-01

    Molecular diagnosis of patients with von Willebrand disease is pending in most populations due to the complexity and high cost of conventional molecular analyses. The need for molecular and clinical characterization of von Willebrand disease in Spain prompted the creation of a multicenter project (PCM-EVW-ES) that resulted in the largest prospective cohort study of patients with all types of von Willebrand disease. Molecular analysis of relevant regions of the VWF , including intronic and promoter regions, was achieved in the 556 individuals recruited via the development of a simple, innovative, relatively low-cost protocol based on microfluidic technology and next-generation sequencing. A total of 704 variants (237 different) were identified along VWF , 155 of which had not been previously recorded in the international mutation database. The potential pathogenic effect of these variants was assessed by in silico analysis. Furthermore, four short tandem repeats were analyzed in order to evaluate the ancestral origin of recurrent mutations. The outcome of genetic analysis allowed for the reclassification of 110 patients, identification of 37 asymptomatic carriers (important for genetic counseling) and re-inclusion of 43 patients previously excluded by phenotyping results. In total, 480 patients were definitively diagnosed. Candidate mutations were identified in all patients except 13 type 1 von Willebrand disease, yielding a high genotype-phenotype correlation. Our data reinforce the capital importance and usefulness of genetics in von Willebrand disease diagnostics. The progressive implementation of molecular study as the first-line test for routine diagnosis of this condition will lead to increasingly more personalized and effective care for this patient population. Copyright© 2017 Ferrata Storti Foundation.

  11. Von willebrand factor cleaving protease activity in the physiopathology of microangiopathic disorders Detección de la actividad de la proteasa que cliva al factor von Willebrand en la patofisiología de las microangiopatías

    Directory of Open Access Journals (Sweden)

    M. M. Amaral

    2003-04-01

    Full Text Available The von Willebrand factor cleaving protease (VWFCP modulates the von Willebrand factor (VWF multimeric size in normal plasma. VWFCP activity levels are decreased in different physiological and pathologic situations. Different techniques have been developed to unfold the purified VWF (perfusion at high shear rate, dialysis against urea in nitrocellulose filters, to detect the VWFCP activity on it (multimeric analysis of VWF, collagen binding to VWF assay and to use the patient plasma both as the source of the enzyme and substrate. In this paper we compared the above mentioned methods with new ones: normal plasma dialyzed on membranes instead of purified VWF, dialysis of the samples against urea in tubing instead of nitrocellulose filters, and sonicated plasma to remove the endogenous VWF. The perfusion assay and detection by multimeric analysis showed a limit of detection (25% of VWFCP activity. Dialysis against urea in both supports and detection by multimeric analysis, showed a better limit of detection (3%, but the recovery of the samples was not as efficient in nitrocellulose filters as it was in tubing. The detection by collagen binding to VWF has more advantages because it allows to analyze more samples than the multimeric analysis does in the same assay. The dialysis of plasma by membranes to obtain the source of exogenous VWF requires no complex equipment. The method, which uses patient plasma as the source of the enzyme and substrate, was inapplicable in our experience because the values could not be interpolated in the reference curve.La proteasa que cliva al factor von Willebrand (VWFCP controla el tamaño multimérico del factor von Willebrand (VWF en plasma normal. Sus niveles se encuentran disminuidos en diferentes situaciones fisiológicas y patológicas. Diferentes técnicas se desarrollaron para desplegar al VWF purificado (perfusión a alta fuerza de cizallamiento, diálisis contra urea en filtros de nitrocelulosa, para detectar

  12. Detection of von Willebrand factor and tissue factor in platelets-fibrin rich coronary thrombi in acute myocardial infarction.

    Science.gov (United States)

    Yamashita, Atsushi; Sumi, Takahiro; Goto, Shinya; Hoshiba, Yasunari; Nishihira, Kensaku; Kawamoto, Riichirou; Hatakeyama, Kinta; Date, Haruhiko; Imamura, Takuroh; Ogawa, Hisao; Asada, Yujiro

    2006-01-01

    The rapid closure of coronary arteries due to occlusive thrombi is the major cause of acute myocardial infarction. However, the mechanisms of coronary thrombus formation have not been elucidated. We immunohistochemically assessed the localizations and their changes over time of glycoprotein IIb/IIIa, fibrin, von Willebrand factor (vWF), and tissue factor (TF), after the onset of chest pain (platelets, fibrin, vWF, and TF from the early phase of onset, and glycoprotein IIb/IIIa and fibrin were closely associated with vWF and TF, respectively. vWF and/or TF may contribute to occlusive thrombus formation and be novel therapeutic candidates for treating patients with coronary thrombosis.

  13. Acquired von Willebrand Syndrome Associated to Secondary IgM MGUS Emerging after Autologous Stem Cell Transplantation for AL Amyloidosis.

    Science.gov (United States)

    Qamar, Hina; Lee, Adrienne; Valentine, Karen; Skeith, Leslie; Jimenez-Zepeda, Victor H

    2017-01-01

    Acquired von Willebrand syndrome (AVWS) is a rare hemorrhagic disorder that occurs in patients with no prior personal or family history of bleeding. Here, we describe a case of AVWS occurring after autologous stem cell transplantation (ASCT). Interestingly, AVWS developed after bortezomib-based induction and conditioning regimens. Recent evidence suggests that the proximity of the bortezomib therapy to the collection of stem cells with consequent depletion of regulatory T cells after the conditioning regimen could explain some of the unusual autoimmune complications reported in patients receiving bortezomib prior to ASCT. In addition, this patient developed a secondary MGUS post-ASCT, which may have also contributed to the AVWS. To the best of our knowledge, this is the first case of post-ASCT AVWS reported. Prospective data is needed to better elucidate the mechanisms by which these unusual complications occur in patients receiving bortezomib prior to ASCT.

  14. Acquired von Willebrand Syndrome associated to secondary IgM MGUS emerging after Autologous Stem Cell Transplantation for AL Amyloidosis

    Directory of Open Access Journals (Sweden)

    Victor H Jimenez-Zepeda

    2017-05-01

    Full Text Available Acquired von Willebrand syndrome (AVWS is a rare hemorrhagic disorder that occurs in patients with no prior personal or family history of bleeding. Here, we describe a case of AVWS occurring after autologous stem cell transplantation (ASCT. Interestingly, AVWS developed after bortezomib-based induction and conditioning regimens. Recent evidence suggests that the proximity of the bortezomib therapy to the collection of stem cells with consequent depletion of regulatory T cells after the conditioning regimen could explain some of the unusual autoimmune complications reported in patients receiving bortezomib prior to ASCT. In addition, this patient developed a secondary MGUS post-ASCT, which may have also contributed to the AVWS. To the best of our knowledge, this is the first case of post-ASCT AVWS reported. Prospective data is needed to better elucidate the mechanisms by which these unusual complications occur in patients receiving bortezomib prior to ASCT.

  15. An immunoradiometric assay for procoagulant factor VIII antigen: results in haemophilia, von Willebrand's disease and fetal plasma and serum

    International Nuclear Information System (INIS)

    Peake, I.R.; Bloom, A.L.; Giddings, J.C.; Ludlam, C.A.

    1979-01-01

    An immunoradiometric assay (IRMA) has been developed based on the inhibitor which arose in a polytransfused severe haemophiliac. The two-site IRMA measured antigens closely associated with the procoagulant parts of the factor VIII complex, which are termed FVIIIC antigens or FVIIICAG. FVIIICAG was present in normal plasma and also, at a slightly lower concentration, in normal serum. In 37 patients with haemophilia A, 36 had FVIIICAG levels of less than 10% of the normal plasma pool. In patients with von Willebrand's disease the levels of FVIIIC and FVIIICAG were in good agreement, both before and after treatment with cryoprecipitate or DDAVP. FVIIICAG was relatively stable in plasma at 37 0 C and could also be detected in cord and fetal serum. The assay is of potential value for detecting reduced levels of factor VIII, for carrier detection and for the prenatal diagnosis of haemophilia. (author)

  16. Establishment and characterization of a new and stable collagen-binding assay for the assessment of von Willebrand factor activity

    Science.gov (United States)

    Ni, Y; Nesrallah, J; Agnew, M; Geske, F J; Favaloro, E J

    2013-01-01

    Introduction Laboratory diagnosis of von Willebrand disease (VWD) requires determination of both von Willebrand factor (VWF) protein levels and activity. Current VWF activity tests include the ristocetin cofactor assay and the collagen-binding assay (VWF:CB). The goal of this investigation is to characterize a new collagen-binding assay and to determine its effectiveness in identifying VWD. Methods Analytical studies were carried out to characterize the performance of a new VWF:CB ELISA. Additionally, samples from a normal population were tested as were well-characterized type 1 and type 2 VWD samples. Results Repeatability and within-laboratory precision studies resulted in coefficients of variation (CVs) of ≤11%. A linear range of 1–354% (0.01–3.54 IU/mL) was determined, along with a limit of detection and a lower limit of quantitation of 1.6% and 4.0% (0.016 and 0.04 IU/mL), respectively. Samples tested from apparently healthy individuals resulted in a normal range of 54–217% (0.54–2.17 IU/mL). Known VWD type 1 and type 2 samples were also analyzed by the ELISA, with 99% of samples having VWF:CB below the normal reference range and an estimated 96% sensitivity and 87% specificity using a VWF collagen-binding/antigen cutoff ratio of 0.50. Conclusion This new VWF:CB ELISA provides an accurate measure of collagen-binding activity that aids in the diagnosis and differentiation of type 1 from type 2 VWD. PMID:23107512

  17. A 12.3-kb Duplication Within the VWF Gene in Pigs Affected by Von Willebrand Disease Type 3

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    Stefanie Lehner

    2018-02-01

    Full Text Available Von Willebrand Disease (VWD type 3 is a serious and sometimes fatal hereditary bleeding disorder. In pigs, the disease has been known for decades, and affected animals are used as models for the human disease. Due to the recessive mode of inheritance of VWD type 3, severe bleeding is typically seen in homozygous individuals. We sequenced the complete porcine VWF (Von Willebrand Factor complementary DNA (cDNA and detected a tandem duplication of exons 17 and 18, causing a frameshift and a premature termination codon (p.Val814LeufsTer3 in the affected pig. Subsequent next generation sequencing on genomic DNA proved the existence of a 12.3-kb tandem duplication associated with VWD. This duplication putatively originates from porcine Short Interspersed Nuclear Elements (SINEs located within VWF introns 16 and 18 with high identity. The premature termination truncates the VWF open reading frame by a large part, resulting in an almost entire loss of the mature peptide. It is therefore supposed to account for the severe VWD type 3. Our results further indicate the presence of strong, nonsense-mediated decay in VWF messenger RNA (mRNA containing the duplication, which was supported by the almost complete absence of the complete VWF protein in immunohistochemistry analysis of the VWD-affected pig. In the past, differentiation of wild-type and heterozygous pigs in this VWD colony had to rely on clinical examinations and additional laboratory methods. The present study provides the basis to distinguish both genotypes by performing a rapid and simple genetic analysis.

  18. Epidemiologic features of von Willebrand's disease in Doberman pinschers, Scottish terriers, and Shetland sheepdogs: 260 cases (1984-1988)

    Science.gov (United States)

    Brooks, M; Dodds, W J; Raymond, S L

    1992-04-15

    During a study period from 1985 through 1988, plasma von Willebrand's factor antigen (vWF:Ag) concentration was measured as a marker for prevalence of the von Willebrand's disease (vWD) trait in Doberman Pinschers (doberman, n = 5,554), Scottish Terriers (scottie, n = 1,363), and Shetland Sheepdogs (sheltie, n = 4,279). Significant increase in prevalence of the trait was seen in scotties and shelties during this period. In 1988, 73% of dobermans, 30% of scotties, and 28% of shelties tested had abnormal vWF:Ag concentration (less than 50% vWF:Ag). We found significant differences between breeds with respect to age and vWF:Ag concentration of clinically affected dogs at time of diagnosis. The affected dobermans were older (doberman mean age, 4.6 years; scottie mean age, 1.7 years; sheltie mean age, 1.9 years) and had higher concentration of plasma vWF:Ag (doberman mean vWF:Ag, 15%; scottie mean vWF:Ag, 0%; sheltie mean vWF:Ag, 8%). Bleeding in affected dogs of all 3 breeds was observed predominantly from mucosal surfaces and from cutaneous sites of surgery or trauma. The most common site of mucosal bleeding in scotties and shelties was oral or nasal cavity, and in dobermans was the urogenital tract. Differences in clinical manifestations of vWD in purebred dogs may reflect heterogeneous defects within the vWF gene, causing a variety of abnormalities in production, structure, and function of vWF protein. Analogous to vWD in human beings, acquired deficiencies of vWF may also contribute to the clinical variability of vWD in dogs.

  19. Testosterone and acute stress are associated with fibrinogen and von Willebrand factor in African men: the SABPA study.

    Science.gov (United States)

    Malan, Nicolaas T; von Känel, Roland; Schutte, Alta E; Huisman, Hugo W; Schutte, Rudolph; Smith, Wayne; Mels, Carina M; Kruger, Ruan; Meiring, Muriel; van Rooyen, Johannes M; Malan, Leoné

    2013-10-12

    Low testosterone, acute and chronic stress and hypercoagulation are all associated with hypertension and hypertension-related diseases. The interaction between these factors and future risk for coronary artery disease in Africans has not been fully elucidated. In this study, associations of testosterone, acute cardiovascular and coagulation stress responses with fibrinogen and von Willebrand factor in African and Caucasian men in a South African cohort were investigated. Cardiovascular variables were studied by means of beat-to-beat and ambulatory blood pressure monitoring. Fasting serum-, salivary testosterone and citrate coagulation markers were obtained from venous blood samples. Acute mental stress responses were evoked with the Stroop test. The African group demonstrated a higher cardiovascular risk compared to Caucasian men with elevated blood pressure, low-grade inflammation, chronic hyperglycemia (HbA1c), lower testosterone levels, and elevated von Willebrand factor (VWF) and fibrinogen levels. Blunted testosterone acute mental stress responses were demonstrated in African males. In multiple regression analyses, higher circulating levels of fibrinogen and VWF in Africans were associated with a low T environment (R(2) 0.24-0.28; p≤0.01), but only circulating fibrinogen in Caucasians. Regarding endothelial function, a low testosterone environment and a profile of augmented α-adrenergic acute mental stress responses (diastolic BP, D-dimer and testosterone) were associated with circulating VWF levels in Africans (Adj R(2) 0.24; pstress, salivary testosterone, D-dimer and vascular responses existed in African males in their association with circulating VWF but no interdependence of the independent variables occurred with fibrinogen levels. © 2013.

  20. Platelet-type von Willebrand Disease: Diagnostic Challenges. Flaws and Pitfalls Experienced in the THROMKID Quality Project.

    Science.gov (United States)

    Maurer, M; Mesters, R; Schneppenheim, R; Knoefler, R; Streif, W

    2015-05-01

    Primary haemostasis defects comprise von Willebrand disease (VWD) and platelet disorders (PD). Although presenting with mild to moderate bleeding tendency in most cases, severe bleeding and blood loss may occur unexpectedly in trauma and surgery. Diagnosis of VWD and PD often remains difficult owing to the wide spectrum of clinical and laboratory manifestations. Platelet-type von Willebrand disease (PT-VWD) is frequently misdiagnosed as type 2B VWD. Discrimination between type 2B VWD and PT-VWD is crucial as treatment differs. A literature review revealed difficulties in diagnostic work-up and choice of optimal treatment of PT-VWD. Guidelines favour the therapeutic use of platelet concentrates. A telephone survey of diagnostic practice with regard to type 2B VWD/PT-VWD was conducted. The prevalence and incidence of type 2B and PT-VWD remained unclear, but PT-VWD may be underestimated. An international study estimated that PT-VWD constitutes up to 15% of the total number of patients diagnosed with type 2B VWD. Our survey confirmed difficulties with diagnosis and showed that some centres did not exclude PT-VWD in type 2B patients. Some authors emphasize that genetic testing is the gold standard for diagnosis, but functional testing allows immediate diagnosis. Due to the important therapeutic implications we suggest that type 2B VWD be confirmed by genetic testing and that in case of a negative result PT-VWD should be excluded. PT-VWD should be excluded in all suspected cases of type 2B. PT-VWD should be treated with platelet concentrates. © Georg Thieme Verlag KG Stuttgart · New York.

  1. Paciente portadora de doença de von Willebrand submetida a cirurgia da valva mitral: uma estratégia para o controle da coagulopatia Patient with von Willebrand disease undergoing mitral valve repair: a strategy for the control of the coagulopathy

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    Ally Nader Roquetti Saroute

    2007-01-01

    Full Text Available Relatamos o caso de uma mulher de 60 anos portadora da doença de von Willebrand tipo I, submetida a cirurgia da valva mitral. A paciente necessitou de cuidados especiais em razão da coagulopatia e foi necessária a utilização de concentrado de fator VIII (VIIIf e fator de von Willebrand (vWf antes, durante e depois da cirurgia. Não houve complicações durante e após a cirurgia. Nove meses depois, a paciente encontra-se assintomática. A correção para valores adequados de VIIIf e vWf permitiu a realização da cirurgia com segurança.We report a case of a 60 year-old woman with von Willebrand disease type I that was submitted to a mitral valve repair. The patient needed special care due coagulopathy and needed VIII factor (VIIIf and von Willebrand factor (vWf, before, during and after surgery. There was no complication during or after surgery. Patient is asymptomatic nine months postoperatively. The correction of VIIIf and vWf allowed the realization of a safety surgery.

  2. Cyclical thrombocytosis, acquired von Willebrand syndrome and aggressive non-melanoma skin cancers are common in patients with Philadelphia-negative myeloproliferative neoplasms treated with hydroxyurea.

    Science.gov (United States)

    Verner, Emma; Forsyth, Cecily; Grigg, Andrew

    2014-05-01

    Abstract Cyclical thrombocytosis, acquired von Willebrand syndrome, aggressive non-melanoma skin cancers and other hydroxyurea complications have been reported in Philadelphia-negative myeloproliferative neoplasms (MPNs), but their incidence and clinical consequences have not been defined in a large cohort of patients. We conducted a retrospective analysis of 188 consecutive patients with MPNs specifically addressing the incidence of these complications. Cyclical thrombocytosis was documented in 29 patients (15%), the majority of whom were receiving hydroxyurea. Acquired von Willebrand syndrome was identified in 17 of the 84 screened patients (20%), but was not associated with any major bleeding complications. Non-melanoma skin cancers were reported in 51 patients (27%). Hydroxyurea-related fever occurred in nine of 149 patients (6%) who received hydroxyurea. Seventy-three patients (39%) experienced a total of 98 major thrombotic events, with the majority of these occurring prior to or within 3 months of the diagnosis. Cyclical thrombocytosis, acquired von Willebrand syndrome, aggressive non-melanoma skin cancers and other hydroxyurea-related complications are not infrequent in MPNs and have important clinical consequences for management.

  3. Elevated levels of von Willebrand factor and high mobility group box 1 (HMGB1) are associated with disease severity and clinical outcome of scrub typhus.

    Science.gov (United States)

    Chen, Hongliu; Ning, Zong; Qiu, Ying; Liao, Yuanli; Chang, Haihua; Ai, Yuanyuan; Wei, Yinghua; Deng, Yiming; Shen, Ying

    2017-08-01

    This study aimed to investigate whether von Willebrand factor (vWF) and high mobility group box 1 (HMGB1) are associated with the severity and clinical outcome of scrub typhus and to seek novel biomarkers for surveillance and prediction of the prognosis of this infection. Serum concentrations of vWF and HMGB1 were measured twice by ELISA for scrub typhus patients (n=103), once prior to doxycycline therapy and then on day 7 of doxycycline therapy; concentrations were measured once for healthy controls (n=32). Among the total 103 patients enrolled, 38 had disease complicated by multiple organ dysfunction syndrome (MODS). Serum concentrations of vWF and HMGB1 were significantly higher in all the patients than in the healthy controls, both prior to doxycycline treatment and on day 7 of doxycycline treatment (pscrub typhus (area under the curve (AUC)=0.864, p=0.001, and AUC=0.862, p=0.001, respectively). Elevated levels of vWF and HMGB1 are associated with the severity and clinical outcome of scrub typhus. These represent possible new biomarkers for use in the assessment and prognostic prediction of this infection. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

  4. Identification and characterization of a novel P2Y 12 variant in a patient diagnosed with type 1 von Willebrand disease in the European MCMDM-1VWD study.

    Science.gov (United States)

    Daly, Martina E; Dawood, Ban B; Lester, William A; Peake, Ian R; Rodeghiero, Francesco; Goodeve, Anne C; Makris, Michael; Wilde, Jonathan T; Mumford, Andrew D; Watson, Stephen P; Mundell, Stuart J

    2009-04-23

    We investigated whether defects in the P2Y(12) ADP receptor gene (P2RY12) contribute to the bleeding tendency in 92 index cases enrolled in the European MCMDM-1VWD study. A heterozygous mutation, predicting a lysine to glutamate (K174E) substitution in P2Y(12), was identified in one case with mild type 1 von Willebrand disease (VWD) and a VWF defect. Platelets from the index case and relatives carrying the K174E defect changed shape in response to ADP, but showed reduced and reversible aggregation in response to 10 muM ADP, unlike the maximal, sustained aggregation observed in controls. The reduced response was associated with an approximate 50% reduction in binding of [(3)H]2MeS-ADP to P2Y(12), whereas binding to the P2Y(1) receptor was normal. A hemagglutinin-tagged K174E P2Y(12) variant showed surface expression in CHO cells, markedly reduced binding to [(3)H]2MeS-ADP, and minimal ADP-mediated inhibition of forskolin-induced adenylyl cyclase activity. Our results provide further evidence for locus heterogeneity in type 1 VWD.

  5. Elevated plasma factor VIII enhances venous thrombus formation in rabbits: contribution of factor XI, von Willebrand factor and tissue factor.

    Science.gov (United States)

    Sugita, Chihiro; Yamashita, Atsushi; Matsuura, Yunosuke; Iwakiri, Takashi; Okuyama, Nozomi; Matsuda, Shuntaro; Matsumoto, Tomoko; Inoue, Osamu; Harada, Aya; Kitazawa, Takehisa; Hattori, Kunihiro; Shima, Midori; Asada, Yujiro

    2013-07-01

    Elevated plasma levels of factor VIII (FVIII) are associated with increased risk of deep venous thrombosis. The aim of this study is to elucidate how elevated FVIII levels affect venous thrombus formation and propagation in vivo. We examined rabbit plasma FVIII activity, plasma thrombin generation, whole blood coagulation, platelet aggregation and venous wall thrombogenicity before and one hour after an intravenous infusion of recombinant human FVIII (rFVIII). Venous thrombus induced by the endothelial denudation of rabbit jugular veins was histologically assessed. Thrombus propagation was evaluated as indocyanine green fluorescence intensity. Argatroban, a thrombin inhibitor, and neutralised antibodies for tissue factor (TF), factor XI (FXI), and von Willebrand factor (VWF) were infused before or after thrombus induction to investigate their effects on venous thrombus formation or propagation. Recombinant FVIII (100 IU/kg) increased rabbit plasma FVIII activity two-fold and significantly enhanced whole blood coagulation and total plasma thrombin generation, but did not affect initial thrombin generation time, platelet aggregation and venous wall thrombogenicity. The rFVIII infusion also increased the size of venous thrombus 1 hour after thrombus induction. Argatroban and the antibodies for TF, FXI or VWF inhibited such enhanced thrombus formation and all except TF suppressed thrombus propagation. In conclusion, elevated plasma FVIII levels enhance venous thrombus formation and propagation. Excess thrombin generation by FXI and VWF-mediated FVIII recruitment appear to contribute to the growth of FVIII-driven venous thrombus.

  6. Analysis of von Willebrand factor A domain-related protein (WARP polymorphism in temperate and tropical Plasmodium vivax field isolates

    Directory of Open Access Journals (Sweden)

    Zakeri Sedigheh

    2009-06-01

    Full Text Available Abstract Background The identification of key molecules is crucial for designing transmission-blocking vaccines (TBVs, among those ookinete micronemal proteins are candidate as a general class of malaria transmission-blocking targets. Here, the sequence analysis of an extra-cellular malaria protein expressed in ookinetes, named von Willebrand factor A domain-related protein (WARP, is reported in 91 Plasmodium vivax isolates circulating in different regions of Iran. Methods Clinical isolates were collected from north temperate and southern tropical regions in Iran. Primers have been designed based on P. vivax sequence (ctg_6991 which amplified a fragment of about 1044 bp with no size variation. Direct sequencing of PCR products was used to determine polymorphism and further bioinformatics analysis in P. vivax sexual stage antigen, pvwarp. Results Amplified pvwarp gene showed 886 bp in size, with no intron. BLAST analysis showed a similarity of 98–100% to P. vivax Sal-I strain; however, Iranian isolates had 2 bp mismatches in 247 and 531 positions that were non-synonymous substitution [T (ACT to A (GCT and R (AGA to S (AGT] in comparison with the Sal-I sequence. Conclusion This study presents the first large-scale survey on pvwarp polymorphism in the world, which provides baseline data for developing WARP-based TBV against both temperate and tropical P. vivax isolates.

  7. Exercise-induced shear stress is associated with changes in plasma von Willebrand factor in older humans.

    Science.gov (United States)

    Gonzales, Joaquin U; Thistlethwaite, John R; Thompson, Benjamin C; Scheuermann, Barry W

    2009-07-01

    Shear stress is the frictional force of blood against the endothelium, a stimulus for endothelial activation and the release of von Willebrand factor (vWF). This study tested the hypothesis that the increase in shear stress associated with exercise correlates with plasma vWF. Young (n = 14, 25.7 +/- 5.4 years) and older (n = 13, 65.6 +/- 10.7 years) individuals participated in 30 min of dynamic handgrip exercise at a moderate intensity. Brachial artery diameter and blood flow were measured using ultrasound Doppler and blood samples were collected before, immediately after, and following 30 min of recovery from exercise with plasma levels of vWF. Plasma levels of vWF increased (P exercise. The change in plasma vWF was linearly correlated with the increase in shear stress during exercise in older individuals (post-exercise: r = 0.78, 30 min recovery: r = 0.77, P < 0.01), but no association was found in the young individuals. These changes in plasma levels of vWF in humans suggest that aging influences endothelial activation and hemostasis.

  8. Space and Time Resolved Detection of Platelet Activation and von Willebrand Factor Conformational Changes in Deep Suspensions.

    Science.gov (United States)

    Biasetti, Jacopo; Sampath, Kaushik; Cortez, Angel; Azhir, Alaleh; Gilad, Assaf A; Kickler, Thomas S; Obser, Tobias; Ruggeri, Zaverio M; Katz, Joseph

    2017-01-01

    Tracking cells and proteins' phenotypic changes in deep suspensions is critical for the direct imaging of blood-related phenomena in in vitro replica of cardiovascular systems and blood-handling devices. This paper introduces fluorescence imaging techniques for space and time resolved detection of platelet activation, von Willebrand factor (VWF) conformational changes, and VWF-platelet interaction in deep suspensions. Labeled VWF, platelets, and VWF-platelet strands are suspended in deep cuvettes, illuminated, and imaged with a high-sensitivity EM-CCD camera, allowing detection using an exposure time of 1 ms. In-house postprocessing algorithms identify and track the moving signals. Recombinant VWF-eGFP (rVWF-eGFP) and VWF labeled with an FITC-conjugated polyclonal antibody are employed. Anti-P-Selectin FITC-conjugated antibodies and the calcium-sensitive probe Indo-1 are used to detect activated platelets. A positive correlation between the mean number of platelets detected per image and the percentage of activated platelets determined through flow cytometry is obtained, validating the technique. An increase in the number of rVWF-eGFP signals upon exposure to shear stress demonstrates the technique's ability to detect breakup of self-aggregates. VWF globular and unfolded conformations and self-aggregation are also observed. The ability to track the size and shape of VWF-platelet strands in space and time provides means to detect pro- and antithrombotic processes.

  9. The thrombospondin-1 N700S polymorphism is associated with early myocardial infarction without altering von Willebrand factor multimer size.

    Science.gov (United States)

    Zwicker, Jeffrey I; Peyvandi, Flora; Palla, Roberta; Lombardi, Rossana; Canciani, Maria Teresa; Cairo, Andrea; Ardissino, Diego; Bernardinelli, Luisa; Bauer, Kenneth A; Lawler, Jack; Mannucci, Pier

    2006-08-15

    The N700S polymorphism of thrombospondin-1 (TSP-1) has been identified as a potential genetic risk factor for myocardial infarction (MI). In a large case-control study of 1425 individuals who survived a myocardial infarction prior to age 45, the N700S polymorphism was a significant risk factor for myocardial infarction in both homozygous (odds ratio [OR] 1.9, 95% confidence interval [CI] 1.1-3.3, P = .01) and heterozygous carriers of the S700 allele (OR 1.4, 95% CI 1.1-3.3, P = .01). TSP-1 has been shown to reduce von Willebrand factor (VWF) multimer size, and the domain responsible for VWF-reducing activity has been localized to the calcium-binding C-terminal sequence. As the N700S polymorphism was previously shown to alter the function of this domain, we investigated whether the altered VWF-reducing activity of TSP-1 underlies the observed prothrombotic phenotype. The TSP1 N700S polymorphism did not influence VWF multimer size in patients homozygous for either allele nor was there a significant reduction of VWF multimer size following incubation with recombinant N700S fragments or platelet-derived TSP-1.

  10. The Carmat Bioprosthetic Total Artificial Heart Is Associated With Early Hemostatic Recovery and no Acquired von Willebrand Syndrome in Calves.

    Science.gov (United States)

    Smadja, David M; Susen, Sophie; Rauch, Antoine; Cholley, Bernard; Latrémouille, Christian; Duveau, Daniel; Zilberstein, Luca; Méléard, Denis; Boughenou, Marie-Fazia; Belle, Eric Van; Gaussem, Pascale; Capel, Antoine; Jansen, Piet; Carpentier, Alain

    2017-10-01

    To determine hemostasis perturbations, including von Willebrand factor (VWF) multimers, after implantation of a new bioprosthetic and pulsatile total artificial heart (TAH). Preclinical study SETTING: Single-center biosurgical research laboratory. Female Charolais calves, 2-to-6 months old, weighing 102-to-122 kg. Surgical implantation of TAH through a mid-sternotomy approach. Four of 12 calves had a support duration of several days (4, 4, 8, and 10 days), allowing for the exploration of early steps of hemostasis parameters, including prothrombin time; coagulation factor levels (II, V, VII+X, and fibrinogen); and platelet count. Multimeric analysis of VWF was performed to detect a potential loss of high-molecular weight (HMW) multimers, as previously described for continuous flow rotary blood pumps. Despite the absence of anticoagulant treatment administered in the postoperative phase, no signs of coagulation activation were detected. Indeed, after an immediate postsurgery decrease of prothrombin time, platelet count, and coagulation factor levels, most parameters returned to baseline values. HMW multimers of VWF remained stable either after initiation or during days of support. Coagulation parameters and platelet count recovery in the postoperative phase of the Carmat TAH (Camat SA, Velizy Villacoublay Cedex, France) implantation in calves, in the absence of anticoagulant treatment and associated with the absence of decrease in HMW multimers of VWF, is in line with early hemocompatibility that is currently being validated in human clinical studies. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Cloning of the cDNA for murine von Willebrand factor and identification of orthologous genes reveals the extent of conservation among diverse species.

    Science.gov (United States)

    Chitta, Mohan S; Duhé, Roy J; Kermode, John C

    2007-05-01

    Interaction of von Willebrand factor (VWF) with circulating platelets promotes hemostasis when a blood vessel is injured. The A1 domain of VWF is responsible for the initial interaction with platelets and is well conserved among species. Knowledge of the cDNA and genomic DNA sequences for human VWF allowed us to predict the cDNA sequence for murine VWF in silico and amplify its entire coding region by RT-PCR. The murine VWF cDNA has an open reading frame of 8,442 bp, encoding a protein of 2,813 amino acid residues with 83% identity to human pre-pro-VWF. The same strategy was used to predict in silico the cDNA sequence for the ortholog of VWF in a further six species. Many of these predictions diverged substantially from the putative Reference Sequences derived by ab initio methods. Our predicted sequences indicated that the VWF gene has a conserved structure of 52 exons in all seven mammalian species examined, as well as in the chicken. There is a minor structural variation in the pufferfish Takifugu rubripes insofar as the VWF gene in this species has 53 exons. Comparison of the translated amino acid sequences also revealed a high degree of conservation. In particular, the cysteine residues are conserved precisely throughout both the pro-peptide and the mature VWF sequence in all species, with a minor exception in the pufferfish VWF ortholog where two adjacent cysteine residues are omitted. The marked conservation of cysteine residues emphasizes the importance of the intricate pattern of disulfide bonds in governing the structure of pro-VWF and regulating the function of the mature VWF protein. It should also be emphasized that many of the conserved features of the VWF gene and protein were obscured when the comparison among species was based on the putative Reference Sequences instead of our predicted cDNA sequences.

  12. Neutrophil Protease Cleavage of Von Willebrand Factor in Glomeruli – An Anti-thrombotic Mechanism in the Kidney

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    Ramesh Tati

    2017-02-01

    Full Text Available Adequate cleavage of von Willebrand factor (VWF prevents formation of thrombi. ADAMTS13 is the main VWF-cleaving protease and its deficiency results in development of thrombotic microangiopathy. Besides ADAMTS13 other proteases may also possess VWF-cleaving activity, but their physiological importance in preventing thrombus formation is unknown. This study investigated if, and which, proteases could cleave VWF in the glomerulus. The content of the glomerular basement membrane (GBM was studied as a reflection of processes occurring in the subendothelial glomerular space. VWF was incubated with human GBMs and VWF cleavage was assessed by multimer structure analysis, immunoblotting and mass spectrometry. VWF was cleaved into the smallest multimers by the GBM, which contained ADAMTS13 as well as neutrophil proteases, elastase, proteinase 3 (PR3, cathepsin-G and matrix-metalloproteinase 9. The most potent components of the GBM capable of VWF cleavage were in the serine protease or metalloprotease category, but not ADAMTS13. Neutralization of neutrophil serine proteases inhibited GBM-mediated VWF-cleaving activity, demonstrating a marked contribution of elastase and/or PR3. VWF-platelet strings formed on the surface of primary glomerular endothelial cells, in a perfusion system, were cleaved by both elastase and the GBM, a process blocked by elastase inhibitor. Ultramorphological studies of the human kidney demonstrated neutrophils releasing elastase into the GBM. Neutrophil proteases may contribute to VWF cleavage within the subendothelium, adjacent to the GBM, and thus regulate thrombus size. This anti-thrombotic mechanism would protect the normal kidney during inflammation and could also explain why most patients with ADAMTS13 deficiency do not develop severe kidney failure.

  13. Relationship between ABO blood groups and von Willebrand factor, ADAMTS13 and factor VIII in patients undergoing hemodialysis.

    Science.gov (United States)

    Rios, Danyelle R A; Fernandes, Ana Paula; Figueiredo, Roberta C; Guimarães, Daniela A M; Ferreira, Cláudia N; Simões E Silva, Ana C; Carvalho, Maria G; Gomes, Karina B; Dusse, Luci Maria Sant' Ana

    2012-05-01

    Several studies have demonstrated that non-O blood groups subjects present an increased VTE risk as compared to those carrying O blood group. The aim of this study was to investigate the ABO blood groups influence on factor VIII (FVIII) activity, von Willebrand factor (VWF), and ADAMTS13 plasma levels in patients undergoing hemodialysis (HD). Patients undergoing HD (N=195) and 80 healthy subjects (control group) were eligible for this cross-sectional study. The ABO blood group phenotyping was performed by the reverse technique. FVIII activity was measured through coagulometric method, and VWF and ADAMTS13 antigens were assessed by ELISA. FVIII activity and VWF levels were significantly higher and ADAMTS13 levels was decreased in HD patients, as compared to healthy subjects (P blood groups showed a significant increase in FVIII activity (P = 0.001) and VWF levels (P blood group. However, no significant difference was observed in ADAMTS13 levels (P = 0.767). In the control group, increased in FVIII activity (P = 0.001) and VWF levels (P = 0.002) and decreased in ADAMTS13 levels (P = 0.005) were observed in subjects carrying non-O blood groups as compared to carriers of O blood group.Our data confirmed that ABO blood group is an important risk factor for increased procoagulant factors in plasma, as FVIII and VWF. Admitting the possible role of kidneys in ADAMTS13 synthesis or on its metabolism, HD patients were not able to increase ADAMTS13 levels in order to compensate the increase of VWF levels mediated by ABO blood groups. Considering that non-O blood groups constitute a risk factor for thrombosis, it is reasonable to admit that A, B and AB HD patients need a careful and continuous follow-up in order to minimize thrombotic events.

  14. Association of ABO blood groups with von Willebrand factor, factor VIII and ADAMTS-13 in patients with lung cancer.

    Science.gov (United States)

    Liu, Xia; Chen, Xiaogang; Yang, Jiezuan; Guo, Renyong

    2017-09-01

    Coagulative and fibrinolytic disorders appear to be associated with the development of lung cancer. The aim of the present study was to determine plasma levels of von Willebrand factor (VWF) and a disintegrin and metalloproteinase with a thrombospondin type 1 motif 13 (ADAMTS-13), and factor VIII (FVIII) activity, in association with O and non-O blood groups in patients with lung cancer. Plasma levels of VWF and ADAMTS-13, and FVIII activity were measured in 115 patients with lung cancer and 98 healthy subjects. Phenotyping of the ABO blood groups was also performed for the two groups. Significantly increased VWF levels and FVIII activity, as well as significantly decreased ADAMTS-13 levels, were observed in patients with distant metastasis as compared with those without distant metastasis and the healthy controls. Plasma VWF levels and FVIII activity were significantly increased in subjects with non-O type blood compared with those with type O blood in the two groups. However, a significant decrease in ADAMTS-13 levels was observed only in the control group among those with non-O type blood, compared with those with type O blood. The results of the present study indicate that increased VWF and decreased ADAMTS-13 levels facilitate the invasiveness and metastasis of lung cancer. Non-O blood groups constitute a risk factor for increased VWF and FVIII in plasma. Continued monitoring of VWF and ADAMTS-13 levels, and of FVIII activity in patients with lung cancer with distinct blood groups may help to minimize the incidence of thrombotic events and improve assessment of disease progression.

  15. Severe Plasmodium falciparum malaria is associated with circulating ultra-large von Willebrand multimers and ADAMTS13 inhibition.

    LENUS (Irish Health Repository)

    Larkin, Deirdre

    2009-03-01

    Plasmodium falciparum infection results in adhesion of infected erythrocytes to blood vessel endothelium, and acute endothelial cell activation, together with sequestration of platelets and leucocytes. We have previously shown that patients with severe infection or fulminant cerebral malaria have significantly increased circulatory levels of the adhesive glycoprotein von Willebrand factor (VWF) and its propeptide, both of which are indices of endothelial cell activation. In this prospective study of patients from Ghana with severe (n = 20) and cerebral (n = 13) P. falciparum malaria, we demonstrate that increased plasma VWF antigen (VWF:Ag) level is associated with disproportionately increased VWF function. VWF collagen binding (VWF:CB) was significantly increased in patients with cerebral malaria and severe malaria (medians 7.6 and 7.0 IU\\/ml versus 1.9 IU\\/ml; p<0.005). This increased VWF:CB correlated with the presence of abnormal ultra-large VWF multimers in patient rather than control plasmas. Concomitant with the increase in VWF:Ag and VWF:CB was a significant persistent reduction in the activity of the VWF-specific cleaving protease ADAMTS13 (approximately 55% of normal; p<0.005). Mixing studies were performed using P. falciparum patient plasma and normal pooled plasma, in the presence or absence of exogenous recombinant ADAMTS13. These studies demonstrated that in malarial plasma, ADAMTS13 function was persistently inhibited in a time-dependent manner. Furthermore, this inhibitory effect was not associated with the presence of known inhibitors of ADAMTS13 enzymatic function (interleukin-6, free haemoglobin, factor VIII or thrombospondin-1). These novel findings suggest that severe P. falciparum infection is associated with acute endothelial cell activation, abnormal circulating ULVWF multimers, and a significant reduction in plasma ADAMTS13 function which is mediated at least in part by an unidentified inhibitor.

  16. Storage of factor VIII variants with impaired von Willebrand factor binding in Weibel-Palade bodies in endothelial cells.

    Directory of Open Access Journals (Sweden)

    Maartje van den Biggelaar

    Full Text Available BACKGROUND: Point mutations resulting in reduced factor VIII (FVIII binding to von Willebrand factor (VWF are an important cause of mild/moderate hemophilia A. Treatment includes desmopressin infusion, which concomitantly increases VWF and FVIII plasma levels, apparently from storage pools containing both proteins. The source of these VWF/FVIII co-storage pools and the mechanism of granule biogenesis are not fully understood. METHODOLOGY/PRINCIPAL FINDINGS: We studied intracellular trafficking of FVIII variants implicated in mild/moderate hemophilia A together with VWF in HEK293 cells and primary endothelial cells. The role of VWF binding was addressed using FVIII variants displaying reduced VWF interaction. Binding studies using purified FVIII proteins revealed moderate (Arg2150His, Del2201, Pro2300Ser to severe (Tyr1680Phe, Ser2119Tyr VWF binding defects. Expression studies in HEK293 cells and primary endothelial cells revealed that all FVIII variants were present within VWF-containing organelles. Quantitative studies showed that the relative amount of FVIII storage was independent of various mutations. Substantial amounts of FVIII variants are co-stored in VWF-containing storage organelles, presumably by virtue of their ability to interact with VWF at low pH. CONCLUSIONS: Our data suggest that the potential of FVIII co-storage with VWF is not affected in mild/moderate hemophilia A caused by reduced FVIII/VWF interaction in the circulation. These data support the hypothesis that Weibel-Palade bodies comprise the desmopressin-releasable FVIII storage pool in vivo.

  17. Performance related factors are the main determinants of the von Willebrand factor response to exhaustive physical exercise.

    Science.gov (United States)

    van Loon, Janine E; Sonneveld, Michelle A H; Praet, Stephan F E; de Maat, Moniek P M; Leebeek, Frank W G

    2014-01-01

    Physical stress triggers the endothelium to release von Willebrand Factor (VWF) from the Weibel Palade bodies. Since VWF is a risk factor for arterial thrombosis, it is of great interest to discover determinants of VWF response to physical stress. We aimed to determine the main mediators of the VWF increase by exhaustive physical exercise. 105 healthy individuals (18-35 years) were included in this study. Each participant performed an incremental exhaustive exercise test on a cycle ergometer. Respiratory gas exchange measurements were obtained while cardiac function was continuously monitored. Blood was collected at baseline and directly after exhaustion. VWF antigen (VWF:Ag) levels, VWF collagen binding (VWF:CB) levels, ADAMTS13 activity and common variations in Syntaxin Binding Protein-5 (STXBP5, rs1039084 and rs9399599), Syntaxin-2 (STX2, rs7978987) and VWF (promoter, rs7965413) were determined. The median VWF:Ag level at baseline was 0.94 IU/mL [IQR 0.8-1.1] and increased with 47% [IQR 25-73] after exhaustive exercise to a median maximum VWF:Ag of 1.38 IU/mL [IQR 1.1-1.8] (pexercise (median increase 43% and 12%, both pexercise (females 1.2 IU/mL; males 1.7 IU/mL, p = 0.001), which was associated by a difference in performance. Genetic variations in STXBP5, STX2 and the VWF promoter were not associated with VWF:Ag levels at baseline nor with the VWF:Ag increase. VWF:Ag levels strongly increase upon exhaustive exercise and this increase is strongly determined by physical fitness level and the intensity of the exercise, while there is no clear effect of genetic variation in STXBP5, STX2 and the VWF promoter.

  18. A pilot study of homocyst(e)ine levels in essential hypertension: relationship to von Willebrand factor, an index of endothelial damage.

    Science.gov (United States)

    Lip, G Y; Edmunds, E; Martin, S C; Jones, A F; Blann, A D; Beevers, D G

    2001-07-01

    An interaction between homocyst(e)ine and the endothelium in hypertensive patients may promote thrombogenesis and atherogenesis, leading to adverse cardiovascular events. We hypothesized that homocyst(e)ine levels are abnormal in patients with essential hypertension, and that this may be related to an adverse effect on the vascular endothelium. Accordingly, we compared plasma levels of homocyst(e)ine and von Willebrand factor (marking endothelial damage) in 83 patients (43 men; mean age 54 +/- standard deviation 15.9 years) with essential hypertension (> 160/90 mm Hg), with levels in 25 healthy normotensive controls (13 men; mean age 56+/-11.8 years). Baseline levels of the markers and other clinical indices were then related to adverse cardiovascular events at follow-up. Plasma homocyst(e)ine (P = .0001) and von Willebrand factor (P = .031) levels were significantly higher in hypertensives compared to controls. After a mean follow-up of 76 patients for 45 months (range, 1 to 66 months), 17 subjects experienced an end point of either cardiovascular death (n = 10) or adverse cardiovascular event (n = 7). Comparing these 17 with the 59 free of an end point, the former were older (P = .0002) and had a longer duration of known hypertension (P = .018). There was a nonsignificant trend toward higher median plasma homocyst(e)ine levels in the patients sustaining a vascular end point (P = .07). In this pilot study, we suggest that essential hypertension may be associated with increased plasma homocyst(e)ine levels, but that this amino acid is unrelated to endothelial damage (von Willebrand factor), clinical indices, or prognosis.

  19. Elevated levels of plasma von Willebrand factor and the risk of macro- and microvascular disease in type 2 diabetic patients with microalbuminuria

    DEFF Research Database (Denmark)

    Gaede, P; Vedel, P; Parving, H H

    2001-01-01

    BACKGROUND: The purpose of this study was to examine the concept suggesting that microalbuminuria in combination with high levels of plasma von Willebrand factor is a stronger predictor for cardiovascular disease and microvascular complications than microalbuminuria alone in type 2 diabetic...... patients. METHODS: One hundred and sixty patients with type 2 diabetes mellitus and persistent microalbuminuria were followed for an average of 3.8 (SD 0.3) years. 70% of the patients were treated with angiotensin converting enzyme (ACE)-inhibitors. Patients in this subanalysis were divided into two groups...... nephropathy or progression in diabetic retinopathy than microalbuminuria alone in patients with type 2 diabetes and persistent microalbuminuria....

  20. Associations Between Diabetic Retinopathy and Plasma Levels of High-sensitive C-reactive Protein or Von Willebrand Factor in Long-term Type 1 Diabetic Patients

    DEFF Research Database (Denmark)

    Laursen, Jonas Vejvad Nørskov; Hoffmann, Stine Skovbo; Green, Anders

    2013-01-01

    .27 IU/ml (0.79-2.07 IU/ml), respectively. No or minimal DR (ETDRS-levels 10-20) was found in 16.4%, mild DR (ETDRS-level 35) in 19.4%, moderate DR (ETDRS-levels 43-47) in 11.0%, and 53.2% had proliferative diabetic retinopathy (PDR) corresponding to ETDRS-level 60 or more. In an age- and sex......Purpose: To evaluate high-sensitive C-reactive protein (hs-CRP) and von Willebrand factor as possible plasma markers of diabetic retinopathy in a population-based cohort of type 1 diabetic patients. Materials and Methods: This was a cross-sectional study of 201 type 1 diabetic patients from...... a population-based cohort from Fyn County, Denmark. Plasma levels of hs-CRP and von Willebrand factor antigen were measured and related to the level of diabetic retinopathy (DR) as evaluated by dilated nine-field 45 degree monoscopic fundus photos captured by Topcon TRC-NWS6 and graded according to the Early...

  1. Cuidados nos pacientes com hemofilia e doença de von Willebrand na cirurgia eletiva otorrinolaringológica

    Directory of Open Access Journals (Sweden)

    Marques Marise P. C.

    2003-01-01

    Full Text Available FORMA DE ESTUDO Clínico prospectivo. MATERIAL E MÉTODO: Foi realizado um estudo prospectivo de 10 anos de 20 pacientes com hemofilias ou doença de von Willebrand (DvW com indicação de cirurgia otorrinolaringológica. Os pacientes foram submetidos a um total de 25 cirurgias otorrinolaringológicas eletivas. A idade média foi de 23,75 anos (2 a 62 anos. O grupo de estudo consistiu em 14 hemofílicos, 11 com hemofilia A grave (1 do sexo feminino, uma portadora com 30% de atividade de fator VIII (FVIII, um hemofílico B leve e uma com deficiência grave de fator X; 6 com DvW, 4 tinham o tipo 1 (3 mulheres, um o tipo 2A e um o tipo 3. Treze hemofílicos tinham síndrome de imunodeficiência adquirida. A duração média do procedimento foi de 1 hora e 37 minutos (15 minutos a 12 horas. O defeito da coagulação foi corrigido com desmopressina (DDAVP, com concentrado de FVIII de pureza intermediária 8Y, com criopreciptado ou com complexo protrombínico não ativado (PPSB, de acordo com os níveis plasmáticos do fator e da severidade da cirurgia. O ácido épsilon aminocapróico também foi usado em associação. Em 1 hemofílico A grave houve sangramento pós-operatório que se resolveu com a elevação do nível mínimo de FVIII para 80% e em 1 paciente com DvW do Tipo 3 houve sangramento pós-operatório pela dificuldade de identificação do melhor concentrado a ser reposto. Após o uso do concentrado de pureza intermediária 8Y, houve controle do sangramento. RESULTADO: Todos os outros pacientes apresentaram a hemostasia considerada normal ou excelente. CONCLUSÃO: Concluiu-se que pacientes com hemofilias ou DvW não apresentam um risco cirúrgico aumentado se for realizada uma terapia adequada.

  2. Performance related factors are the main determinants of the von Willebrand factor response to exhaustive physical exercise.

    Directory of Open Access Journals (Sweden)

    Janine E van Loon

    Full Text Available Physical stress triggers the endothelium to release von Willebrand Factor (VWF from the Weibel Palade bodies. Since VWF is a risk factor for arterial thrombosis, it is of great interest to discover determinants of VWF response to physical stress. We aimed to determine the main mediators of the VWF increase by exhaustive physical exercise.105 healthy individuals (18-35 years were included in this study. Each participant performed an incremental exhaustive exercise test on a cycle ergometer. Respiratory gas exchange measurements were obtained while cardiac function was continuously monitored. Blood was collected at baseline and directly after exhaustion. VWF antigen (VWF:Ag levels, VWF collagen binding (VWF:CB levels, ADAMTS13 activity and common variations in Syntaxin Binding Protein-5 (STXBP5, rs1039084 and rs9399599, Syntaxin-2 (STX2, rs7978987 and VWF (promoter, rs7965413 were determined.The median VWF:Ag level at baseline was 0.94 IU/mL [IQR 0.8-1.1] and increased with 47% [IQR 25-73] after exhaustive exercise to a median maximum VWF:Ag of 1.38 IU/mL [IQR 1.1-1.8] (p<0.0001. VWF:CB levels and ADAMTS13 activity both also increased after exhaustive exercise (median increase 43% and 12%, both p<0.0001. The strongest determinants of the VWF:Ag level increase are performance related (p<0.0001. We observed a gender difference in VWF:Ag response to exercise (females 1.2 IU/mL; males 1.7 IU/mL, p = 0.001, which was associated by a difference in performance. Genetic variations in STXBP5, STX2 and the VWF promoter were not associated with VWF:Ag levels at baseline nor with the VWF:Ag increase.VWF:Ag levels strongly increase upon exhaustive exercise and this increase is strongly determined by physical fitness level and the intensity of the exercise, while there is no clear effect of genetic variation in STXBP5, STX2 and the VWF promoter.

  3. von Willebrand Factor Test

    Science.gov (United States)

    ... with infections, inflammation, trauma, and with physical and emotional stressors. They are also increased with pregnancy and with the use of estrogen medications such as oral contraceptives. Is there anything else I should know? A ...

  4. von Willebrand Disease

    Science.gov (United States)

    ... results from a physical exam and tests. Medical History Your doctor will likely ask questions about your ... a medical center that specializes in high-risk obstetrics and has a hematologist on staff for prenatal ...

  5. Endothelial markers in malignant vascular tumours of the liver: superiority of QB-END/10 over von Willebrand factor and Ulex europaeus agglutinin 1.

    Science.gov (United States)

    Anthony, P P; Ramani, P

    1991-01-01

    A new monoclonal antibody, QB-END/10, raised against the CD34 antigen in human endothelial cell membranes and haemopoietic progenitor cells, was studied for its usefulness as a marker of neoplastic vascular cells in 21 angiosarcomas and seven malignant haemangioendotheliomas of the liver. QB-END/10 was both more sensitive and more specific than Von Willebrand factor (VWF) and Ulex europaeus 1 agglutinin (UEA-1) in labelling endothelial cells and it did not cross react with epithelia as UEA-1 often does. Staining was uniformly strong and clear in all histological variants of these two tumours. QB-END/10 should prove particularly useful in the differential diagnosis of malignant vascular tumours of the liver.

  6. Descripción de un inmunoensayo enzimático que reconoce anticuerpos anti-factor VIII/von Willebrand obtenidos a partir de hibridomas múridos Description of an enzime immunoassay that recognizes anti-factor VIII/von Willebrand antibodies obtained from murine hybridomas

    Directory of Open Access Journals (Sweden)

    Renée González Sampedro

    1999-04-01

    Full Text Available Se describe un inmunoensayo enzimático (ELISA que detecta anticuerpos anti-Factor-VIII/von Willebrand (FVIII/vW, con una relación de enlace > 5, que permite reconocer dichos anticuerpos tempranamente en los cultivos de hibridomas múridos. Para la adsorción de las placas del inmunoensayo se utilizaron preparados semipurificados de FVIII/vW obtenidos en Cuba. Se inmunizaron ratones Balb/c con la finalidad de generar los anticuerpos monoclonales detectados por este ELISA. Se obtuvo un clon con crecimiento estable y varios subclones positivos por el ELISA con actividad biológica específica de anticuerpos inhibidores de FVIIIAn enzime immunoassay (ELISA that detects anti-Factor VIII/von Willebrand (FVIII/vw antibodies with a binding relationship > 5 that allows the early recognition of such antibodies in the cultures of murine hybridomas is described. Semipurified preparations of FVIII/vw obtained in Cuba were used for the adsorption of the immunoassay plates. Balb/c mice were immunized in order to generate the monoclonal antibodies detected by this ELISA. A clone with stable growth and several positive subclones were obtained by ELISA with specific biological activity of FVIII-inhibiting antibodies

  7. Comparative study on collagen-binding enzyme-linked immunosorbent assay and ristocetin cofactor activity assays for detection of functional activity of von Willebrand factor.

    Science.gov (United States)

    Turecek, Peter L; Siekmann, Jürgen; Schwarz, Hans Peter

    2002-04-01

    For more than two decades, the ristocetin cofactor (RCo) assay, which measures the von Willebrand factor (vWF)-mediated agglutination of platelets in the presence of the antibiotic ristocetin, has been the most common method for measuring the functional activity of vWF. There is, however, general agreement among clinical analysts that this method has major practical disadvantages in performance and reproducibility. Today, collagen-binding assays (CBA) based on the enzyme-linked immunosorbent assay (ELISA) technique that measure the interaction of vWF and collagen are an alternative analytic procedure based on a more physiological function than that of the RCo procedure. We used both assay systems in a comparative study to assess the functional activity of vWF in plasma as well as in therapeutic preparations. We measured RCo activities of plasma from healthy donors and patients with different types of von Willebrand disease (vWD) and of vWF as a drug substance in factor (F) VIII/vWF concentrates using both the aggregometric and the macroscopic methods. In addition, we measured collagen-binding activity (vWF:CB) using a recently developed commercially available CBA system. To investigate the relation between the structure and the functional activity of vWF, we isolated vWF species with different numbers of multimers from FVIII/vWF concentrates by affinity chromatography on immobilized heparin. The vWF:RCo and vWF:CB of the different fractions were measured, and the multimeric structure of vWF was analyzed by sodium dodecyl sulfate (SDS) agarose gel electrophoresis. (vWF:CB and vWF:RCo are part of the nomenclature proposed by the International Society on Thrombosis and Hemostasis Scientific and Standardization Committee [ISTH SSC] subcommittee on von Willebrand factor, in Maastricht, Germany, June 16, 2000.) Measurement of functional vWF activity by CBA can be carried out with substantially higher interassay reproducibility than can measurement of RCo. Both assay

  8. Influences of ABO blood group, age and gender on plasma coagulation factor VIII, fibrinogen, von Willebrand factor and ADAMTS13 levels in a Chinese population.

    Science.gov (United States)

    Wang, Zongkui; Dou, Miaomiao; Du, Xi; Ma, Li; Sun, Pan; Cao, Haijun; Ye, Shengliang; Jiang, Peng; Liu, Fengjuan; Lin, Fangzhao; Zhang, Rong; Li, Changqing

    2017-01-01

    ABO blood group is a hereditary factor of plasma levels of coagulation factor VIII (FVIII) and von Willebrand factor (VWF). Age and gender have been shown to influence FVIII, VWF, fibrinogen (Fbg), and ADAMTS13 (A disintegrin and metalloprotease with thrombospondin type 1 motif, 13). We investigated the effects of ABO type, age, and gender on plasma levels of FVIII, Fbg, VWF, and ADAMTS13 in a Chinese population. A total of 290 healthy volunteers were eligible for this study. ABO blood group was determined by indirect technique. FVIII:C and Fbg were measured by clotting assays. VWF antigen (VWF:Ag), collagen-binding activity (VWF:CBA), and ADAMTS13 antigen were assessed by ELISA, whereas VWF ristocetin cofactor activity (VWF:Rcof) was performed by agglutination of platelets with ristocetin. Mean FVIII:C and VWF levels (VWF:Ag, VWF:CBA, and VWF:Rcof) were significantly higher in non-O than in O type subjects ( p  blood group, age, and gender showed different effects on plasma levels of FVIII:C, Fbg, VWF:Ag, VWF:CBA, VWF:Rcof, and ADAMTS13 antigen. These new data on a Chinese population are quite helpful to compare with other ethnic groups.

  9. Thrombomodulin, von Willebrand factor and E-selectin as plasma markers of endothelial damage/dysfunction and activation in pregnancy induced hypertension.

    Science.gov (United States)

    Nadar, Sunil K; Al Yemeni, Eman; Blann, Andrew D; Lip, Gregory Y H

    2004-01-01

    Endothelial disturbance (whether activation, dysfunction or damage) is a likely pathogenic mechanism in pre-eclampsia and pregnancy-induced hypertension (PIH). We set out to determine which of three plasma markers of endothelial disturbance, indicating endothelial activation (E-selectin) or damage/dysfunction (von Willebrand factor (vWf), soluble thrombomodulin), would provide the best discriminator of PIH compared to normotensive pregnancy. Cross-sectional study of 36 consecutive women with PIH (age 31+/-6 years) and 36 consecutive women with normotensive pregnancies (age 29+/-5 years) of similar parity. Plasma levels of vWf, E-selectin and thrombomodulin were measured using ELISA. As expected, women with PIH had significantly higher levels of plasma vWf (by 19%, p=0.003), E-selectin (by 40%, p<0.001) and thrombomodulin (by 61%, p=0.01) than normotensive women. However, on stepwise multiple regression analysis, only thrombomodulin was an independent significant predictor of the presence of PIH (p=0.023). We conclude that although vWf, E-selectin and thrombomodulin are all raised in PIH, only thrombomodulin was independently associated with PIH. This molecule could potentially be useful in monitoring and in providing clues in aetiology and pathophysiology, and may have implications for the clinical complications associated with PIH.

  10. Characterization of an entomopathogenic fungi target integument protein, Bombyx mori single domain von Willebrand factor type C, in the silkworm, Bombyx mori.

    Science.gov (United States)

    Han, F; Lu, A; Yuan, Y; Huang, W; Beerntsen, B T; Huang, J; Ling, E

    2017-06-01

    The insect cuticle works as the first line of defence to protect insects from pathogenic infections and water evaporation. However, the old cuticle must be shed in order to enter the next developmental stage. During each ecdysis, moulting fluids are produced and secreted into the area among the old and new cuticles. In a previous study, the protein Bombyx mori single domain von Willebrand factor type C (BmSVWC; BGIBMGA011399) was identified in the moulting fluids of Bo. mori and demonstrated to regulate ecdysis. In this study we show that in Bo. mori larvae, BmSVWC primarily locates to the integument (epidermal cells and cuticle), wing discs and head. During the moulting stage, BmSVWC is released into the moulting fluids, and is then produced again by epidermal cells after ecdysis. Fungal infection was shown to decrease the amount of BmSVWC in the cuticle, which indicates that BmSVWC is a target protein of entomopathogenic fungi. Thus, BmSVWC is mainly involved in maintaining the integrity of the integument structure, which serves to protect insects from physical damage and pathogenic infection. © 2017 The Royal Entomological Society.

  11. Use of routine histopathology and factor VIII-related antigen/von Willebrand factor immunohistochemistry to differentiate primary hemangiosarcoma of bone from telangiectatic osteosarcoma in 54 dogs.

    Science.gov (United States)

    Giuffrida, M A; Bacon, N J; Kamstock, D A

    2017-12-01

    Hemangiosarcoma (HSA) of bone and telangiectatic osteosarcoma (tOSA) can appear similar histologically, but differ in histogenesis (malignant endothelial cells versus osteoblasts), and may warrant different treatments. Immunohistochemistry (IHC) for endothelial cell marker factor VIII-related antigen/von Willebrand factor (FVIII-RAg/vWF) is a well-documented ancillary test to confirm HSA diagnoses in soft tissues, but its use in osseous HSA is rarely described. Archived samples of 54 primary appendicular bone tumours previously diagnosed as HSA or tOSA were evaluated using combination routine histopathology (RHP) and IHC. Approximately 20% of tumours were reclassified on the basis of FVIII-RAg/vWF immunoreactivity, typically from an original diagnosis of tOSA to a reclassified diagnosis of HSA. No sample with tumour osteoid clearly identified on RHP was immunopositive for FVIII-RAg/vWF. RHP alone was specific but not sensitive for diagnosis of HSA, compared with combination RHP and IHC. Routine histopathological evaluation in combination with FVIII-RAg/vWF IHC can help differentiate canine primary appendicular HSA from tOSA. © 2016 John Wiley & Sons Ltd.

  12. One-pot preparation of conducting composite containing abundant amino groups on electrode surface for electrochemical detection of von willebrand factor

    Science.gov (United States)

    Wang, Wen; Ma, Chao; Li, Yi; Liu, Baihui; Tan, Liang

    2018-03-01

    A one-pot protocol based on cyclic voltammetric scan was employed to prepare new conducting composite that was abundant in amino groups. The scanning electron microscope, atomic force microscope, X-ray photoelectron spectroscopy and infrared spectrum characterization demonstrate that poly(azure A), gold nanoparticles, chitosan and cysteine were immobilized simultaneously on glassy carbon electrode surface. Von Willebrand factor (vWF) antibody (Ab) was subsequently assembled by using glutaraldehyde to construct the Ab/composite-modified electrode. The capture of vWF could inhibit the charge transfer between the ferri-/ferrocyanide probe and the electrode and exert the negative effect on the electrochemical response of the dye polymer in the conducting composite due to the strong steric hindrance effect. The DPV peak current change before and after the immunoreaction was found to be proportional to the logarithm of the vWF concentration from 0.001 to 100 μg mL-1 with a detection limit of 0.4 ng mL-1. The proposed label-free electrochemical method was employed in the investigation on the release of vWF by oxidation-injured vascular endothelial cells. The experimental results exhibit that the vWF content in growth medium was increased when the oxidation injury of the cells was intensified in the presence of H2O2.

  13. Molecular cloning of the human gene for von Willebrand factor and identification of the transcription initiation site

    International Nuclear Information System (INIS)

    Collins, C.J.; Underdahl, J.P.; Levene, R.B.; Ravera, C.P.; Morin, M.J.; Dombalagian, M.J.; Ricca, G.; Livingston, D.M.; Lynch, D.C.

    1987-01-01

    A series of overlapping cosmid genomic clones have been isolated that contain the entire coding unit of the human gene for van Willebrand factor (vWf), a major component of the hemostatic system. The cloned segments span ≅ 175 kilobases of human DNA sequence, and hybridization analysis suggest that the vWf coding unit is ≅150 kilobases in length. Within one of these clones, the vWF transcription initiation site has been mapped and a portion of the vWf promoter region has been sequenced, revealing a typical TATA box, a downstream CCAAT box, and a perfect downstream repeat of the 8 base pairs containing the transcription start site. Sequencing of a segment of another genomic clone has revealed the vWF translation termination codon. Where tested, comparative restriction analysis of cloned and chromosomal DNA segments strongly suggests that no major alterations occurred during cloning and that there is only one complete copy of the vWf gene in the human haploid genome. Similar analyses of DNA from vWf-producing endothelial cells and nonexpressing leukocytes suggest that vWf gene expression is not accompanied by gross genomic rearrangements. In addition, there is significant homology of C-terminal coding sequences among the vWf genes of several vertebrate species

  14. von Willebrand factor and its cleaving protease ADAMTS13 balance in coronary artery vessels: Lessons learned from thrombotic thrombocytopenic purpura. A narrative review.

    Science.gov (United States)

    Morici, Nuccia; Cantoni, Silvia; Panzeri, Francesco; Sacco, Alice; Rusconi, Chiara; Stucchi, Miriam; Oliva, Fabrizio; Cattaneo, Marco

    2017-07-01

    Deficiency of the von Willebrand factor-cleaving protease ADAMTS13 is central to the pathophysiology of thrombotic thrombocytopenic purpura (TTP), a microangiopathic syndrome that presents as an acute medical emergency. In this review we will explore the evidence of a two-way relationship between TTP and ACS. Moreover, we will review the evidence emerged from epidemiological studies of an inverse relationship between the plasma levels of ADAMTS13 and the risk of ACS. Pubmed, MEDLINE and EMBASE, CINHAL, COCHRANE and Google Scholar databases were searched from inception to January 2017. The search yielded 43 studies representing 23 unique patient cases, 5 case series, 5 cohort studies and 10 case-control studies. Most ACS cases developing in the setting of TTP resolved with standard treatment of the underlying microangiopathy, with only a few requiring coronary invasive management. Antiplatelet therapy was not usually prescribed and all of the currently used P2Y 12 were felt to be a potential trigger for a TTP-like syndrome, although our review revealed that the occurrence of TTP in patients treated with new P2Y 12 antagonists is rare. Most studies confirmed the inverse association among ADAMTS13 levels and ACS. The heart is a definite target organ in TTP. The clinical spectrum of its involvement is probably influenced by local factors that add on to the systemic deficiency characteristic of TTP. It follows that patients with TTP should be carefully monitored for ACS events, especially when multiple risk factors for coronary disease exist. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Influence of atrial fibrillation on plasma von willebrand factor, soluble E-selectin, and N-terminal pro B-type natriuretic peptide levels in systolic heart failure.

    Science.gov (United States)

    Freestone, Bethan; Gustafsson, Finn; Chong, Aun Yeong; Corell, Pernille; Kistorp, Caroline; Hildebrandt, Per; Lip, Gregory Y H

    2008-05-01

    Endothelial dysfunction is present in patients with heart failure (HF) due to left ventricular systolic dysfunction, as well as in patients with atrial fibrillation (AF) who have normal cardiac function. It is unknown whether AF influences the degree of endothelial dysfunction in patients with systolic HF. We measured levels of plasma von Willebrand factor (vWF) and E-selectin (as indexes of endothelial damage/dysfunction and endothelial activation, respectively; both enzyme-linked immunosorbent assay) in patients with AF and HF (AF-HF), who were compared to patients with sinus rhythm and HF (SR-HF), as well as in age-matched, healthy, control subjects. We also assessed the relationship of vWF and E-selectin to plasma N-terminal pro B-type natriuretic peptide (NTpro-BNP), a marker for HF severity and prognosis. One hundred ninety patients (73% men; mean age, 69.0 +/- 10.1 years [+/- SD]) with systolic HF were studied, who were compared to 117 healthy control subjects: 52 subjects (27%) were in AF, while 138 subjects (73%) were in sinus rhythm. AF-HF patients were older than SR-HF patients (p = 0.046), but left ventricular ejection fraction and New York Heart Association class were similar. There were significant differences in NT-proBNP (p NT-proBNP (p NT-proBNP levels (Spearman r = 0.139; p = 0.017). There is evidence of greater endothelial damage/dysfunction in AF-HF patients when compared to SR-HF patients. The clinical significance of this is unclear but may have prognostic value.

  16. Analysis of expression of von Willebrand factor, endothelin-1, vascular endothelial growth factor in Budd-Chiari syndrome with membranous obstruction

    International Nuclear Information System (INIS)

    Han Xinqiang; Zu Maoheng

    2011-01-01

    Objective: To investigate whether the injured vascular endothelial plays an important role in the membranous formation of the inferior vena cava (IVC). Methods: There were 40 cases of membranous obstruction of inferior vena cava (MOVC) in the experimental group and 40 arrhythmic inpatients in the control group from affiliated hospital. There were 23 males and 17 females in experimental group while 21 males and 19 females in control group, and the age were (41.8±8.1) yrs and (43.2± 7.6) yrs respectively. All of them had no anti-coagulation (clotting) drug history and smoking history, no hypertension, no pulmonary artery hypertension, no coronary heart disease, no valvular disease, no myocardial disease, no blood disease, no diabetes, no connective tissue disease and malignancy, and liver and renal function must be normal. And then the serum concentrations of von Willebrand factor (vWF), endothelin-l (ET-1), vascular endothelial growth factor (VEGF) were defined by enzyme-linked immunosorbent assay (ELISA). The results were analyzed with independent sample t-test. Results: In MOVC patients, the serum concentrations of vWF, ET-1 and VEGF [(37.8±6.6) μg/L, (31.9± 6.0) ng/L, (20.84±5.78) μg/L] were higher than those in the control group [(3.3±1.3) μg/L, (5.3±1.8) ng/L, (4.2±1.2) μg/L. t=32.65, 26.70, 17.85, P<0.01, respectively]. Conclusions: The injury of vascular endothelium is related to the formation of membrane in the IVC. (authors)

  17. Assembly and activation of alternative complement components on endothelial cell-anchored ultra-large von Willebrand factor links complement and hemostasis-thrombosis.

    Directory of Open Access Journals (Sweden)

    Nancy A Turner

    Full Text Available Vascular endothelial cells (ECs express and release protein components of the complement pathways, as well as secreting and anchoring ultra-large von Willebrand factor (ULVWF multimers in long string-like structures that initiate platelet adhesion during hemostasis and thrombosis. The alternative complement pathway (AP is an important non-antibody-requiring host defense system. Thrombotic microangiopathies can be associated with defective regulation of the AP (atypical hemolytic-uremic syndrome or with inadequate cleavage by ADAMTS-13 of ULVWF multimeric strings secreted by/anchored to ECs (thrombotic thrombocytopenic purpura. Our goal was to determine if EC-anchored ULVWF strings caused the assembly and activation of AP components, thereby linking two essential defense mechanisms.We quantified gene expression of these complement components in cultured human umbilical vein endothelial cells (HUVECs by real-time PCR: C3 and C5; complement factor (CF B, CFD, CFP, CFH and CFI of the AP; and C4 of the classical and lectin (but not alternative complement pathways. We used fluorescent microscopy, monospecific antibodies against complement components, fluorescent secondary antibodies, and the analysis of >150 images to quantify the attachment of HUVEC-released complement proteins to ULVWF strings secreted by, and anchored to, the HUVECs (under conditions of ADAMTS-13 inhibition. We found that HUVEC-released C4 did not attach to ULVWF strings, ruling out activation of the classical and lectin pathways by the strings. In contrast, C3, FB, FD, FP and C5, FH and FI attached to ULVWF strings in quantitative patterns consistent with assembly of the AP components into active complexes. This was verified when non-functional FB blocked the formation of AP C3 convertase complexes (C3bBb on ULVWF strings.AP components are assembled and activated on EC-secreted/anchored ULVWF multimeric strings. Our findings provide one possible molecular mechanism for clinical

  18. The important role of von Willebrand factor in platelet-derived FVIII gene therapy for murine hemophilia A in the presence of inhibitory antibodies.

    Science.gov (United States)

    Shi, Q; Schroeder, J A; Kuether, E L; Montgomery, R R

    2015-07-01

    Our previous studies have demonstrated that targeting FVIII expression to platelets results in FVIII storage together with von Willebrand factor (VWF) in platelet α-granules and that platelet-derived FVIII (2bF8) corrects the murine hemophilia A phenotype even in the presence of high-titer anti-FVIII inhibitory antibodies (inhibitors). To explore how VWF has an impact on platelet gene therapy for hemophilia A with inhibitors. 2bF8 transgenic mice in the FVIII(-/-) background (2bF8(tg+/-) F8(-/-) ) with varying VWF phenotypes were used in this study. Animals were analyzed by VWF ELISA, FVIII activity assay, Bethesda assay and tail clip survival test. Only 18% of 2bF8(tg+/-) F8(-/-) VWF(-/-) animals, in which VWF was deficient, survived the tail clip challenge with inhibitor titers of 3-8000 BU mL(-1) . In contrast, 82% of 2bF8(tg+/-) F8(-/-) VWF(+/+) mice, which had normal VWF levels, survived tail clipping with inhibitor titers of 10-50,000 BU mL(-1) . All 2bF8(tg+/-) F8(-/-) VWF(-/-) mice without inhibitors survived tail clipping and no VWF(-/-) F8(-/-) mice survived this challenge. Because VWF is synthesized by endothelial cells and megakaryocytes and is distributed in both plasma and platelets in peripheral blood, we further investigated the effect of each compartment of VWF on platelet-FVIII gene therapy for hemophilia A with inhibitors. In the presence of inhibitors, 42% of animals survived tail clipping in the group with plasma-VWF and 50% survived in the platelet-VWF group. VWF is essential for platelet gene therapy for hemophilia A with inhibitors. Both platelet-VWF and plasma-VWF are required for optimal platelet-derived FVIII gene therapy for hemophilia A in the presence of inhibitors. © 2015 International Society on Thrombosis and Haemostasis.

  19. Labor management in a patient with on willebrand

    International Nuclear Information System (INIS)

    Saaqib, S.

    2007-01-01

    von Willebrand disease (VWD) is an inherited bleeding disorder involving a deficiency or abnormal function of a blood clotting protein called von Willebrand factor (VWF). Deficiency of VWF, therefore, shows primarily in organs with small blood vessels such as the skin, the gastrointestinal tract and the uterus. This case report describes management of a patient presenting with type II von Willebrand disease in labor. She had history of lifethreatening hemorrhage from an operation for deviated nasal septum and had a risk of severe postpartum hemorrhage (PPH) within 48 hours of delivery, which was avoided by appropriate planning and timely management. (author)

  20. J-GLOBAL MeSH Dictionary: von Willebrand病 [MeCab user dictionary for science technology term[Archive

    Lifescience Database Archive (English)

    Full Text Available MeCab user dictionary for science technology term von Willebrand病 名詞 一般 * * * * von Willebrand...病 ... MeSH D014842 200906053707829497 C LS51 UNKNOWN_2 von Willebrand

  1. Relationship between ADAMTS13 activity, von Willebrand factor antigen levels and platelet function in the early and late phases after TIA or ischaemic stroke.

    Science.gov (United States)

    McCabe, Dominick J H; Murphy, Stephen J X; Starke, Richard; Harrison, Paul; Brown, Martin M; Sidhu, Paul S; Mackie, Ian J; Scully, Marie; Machin, Samuel J

    2015-01-15

    Reduced ADAMTS13 activity is seen in thrombotic thrombocytopenic purpura (TTP), and may lead to accumulation of prothrombotic ultra-large von Willebrand factor (ULVWF) multimers in vivo. ADAMTS13 activity and its relationship with VWF antigen (VWF:Ag) levels and platelet function in 'non-TTP related' TIA or ischaemic stroke has not been comprehensively studied. In this prospective pilot observational analytical case-control study, ADAMTS13 activity and VWF:Ag levels were quantified in platelet poor plasma in 53 patients in the early phase (≤ 4 weeks) and 34 of these patients in the late phase (≥ 3 months) after TIA or ischaemic stroke on aspirin. Data were compared with those from 22 controls not on aspirin. The impact of ADAMTS13 on platelet function in whole blood was quantified by measuring Collagen-ADP (C-ADP) and Collagen-Epinephrine closure times on a platelet function analyser (PFA-100(®)). Median ADAMTS13 activity was significantly reduced in the early phase (71.96% vs. 95.5%, P TIA or stroke compared with controls (86.3% vs. 95.5%, P=0.19). There was a significant inverse relationship between ADAMTS13 activity and VWF:Ag levels in the early phase (r=-0.31; P=0.024), but not in the late phase after TIA or stroke (P=0.74). There was a positive correlation between ADAMTS13 activity and C-ADP closure times in early phase patients only, likely mediated via VWF:Ag levels. ADAMTS13 activity is reduced and VWF:Ag expression is increased within 4 weeks of TIA or ischaemic stroke onset, and can promote enhanced platelet adhesion and aggregation in response to stimulation with collagen and ADP via VWF-mediated pathways. These data improve our understanding of the dynamic haemostatic and thrombotic profiles of ischaemic cerebrovascular disease (CVD) patients, and are important in view of the potential future role that ADAMTS13 may have to play as an anti-thrombotic agent in CVD. Copyright © 2014 Elsevier B.V. All rights reserved.

  2. von Willebrand Disease (For Parents)

    Science.gov (United States)

    [Skip to Content] for Parents Parents site Sitio para padres General Health Growth & Development Infections Diseases & Conditions Pregnancy & Baby Nutrition & Fitness Emotions & Behavior School & Family ...

  3. Functional characterisation of the type 1 von Willebrand disease candidate VWF gene variants: p.M771I, p.L881R and p.P1413L.

    Science.gov (United States)

    Berber, Ergul; Ozbil, Mehmet; Brown, Christine; Baslar, Zafer; Caglayan, S Hande; Lillicrap, David

    2017-10-01

    Abnormalities in the biosynthetic pathway or increased clearance of plasma von Willebrand factor (VWF) are likely to contribute to decreased plasma VWF levels in inherited type 1 von Willebrand disease (VWD). Recent studies demonstrated that 65% of type 1 VWD patients have candidate VWF mutations, the majority of which are missense variants. The purpose of this study was to explore the effects of three VWF missense mutations (p.M771I, p.L881R and p.P1413L) located in different functional domains of VWF, reported as candidate mutations in type 1 VWD patients in the course of the MCMDM-1VWD study. The focus of these studies was on the intracellular biosynthetic processing and localisation of VWF in a heterologous cell system. Molecular dynamic simulation for p.M771I and p.P1413L was also performed to analyse the conformational effects of the changes. As determined by immunofluorescence antibody staining and confocal microscopy of HEK293 cells, the intracellular localisation of recombinant VWF with the p.M771I variation was impaired. Transient transfection studies and phorbol myristate acetate stimulation in COS-7 cells revealed significant intracellular retention. In addition, major loss of VWF multimers was observed for only the p.M771I mutation. Molecular dynamic simulations on p.M771I mutant VWF revealed distinct structural rearrangements including a large deviation in the E' domain, and significant loss of β-sheet secondary structure. The pathogenic effects of candidate VWF gene mutations were explored in this study. In vitro expression studies in heterologous cell systems revealed impaired secretion of VWF and a dominant negative effect on the processing of the wild-type protein for only the p.M771I mutation and none of the mutations affected the regulated secretion.

  4. Consumption of nattokinase is associated with reduced blood pressure and von Willebrand factor, a cardiovascular risk marker: results from a randomized, double-blind, placebo-controlled, multicenter North American clinical trial

    Directory of Open Access Journals (Sweden)

    Jensen GS

    2016-10-01

    Full Text Available Gitte S Jensen,1 Miki Lenninger,1 Michael P Ero,2 Kathleen F Benson,1 1NIS Labs, Klamath Falls, OR, 2Machaon Diagnostics, Inc., Oakland, CA, USA Objective: The objective of this study is to evaluate the effects of consumption of nattokinase on hypertension in a North American hypertensive population with associated genetic, dietary, and lifestyle factors. This is in extension of, and contrast to, previous studies on Asian populations.Materials and methods: A randomized, double-blind, placebo-controlled, parallel-arm clinical study was performed to evaluate nattokinase (NSK-SD, a fermented soy extract nattō from which vitamin K2 has been removed. Based on the results from previous studies on Asian populations, 79 subjects were enrolled upon screening for elevated blood pressure (BP; systolic BP ≥130 or diastolic BP ≥90 mmHg who consumed placebo or 100 mg nattokinase/d for the 8-week study duration. Blood collections were performed at baseline and 8 weeks for testing plasma renin activity, von Willebrand factor (vWF, and platelet factor-4. Seventy-four people completed the study with good compliance.Results: Consumption of nattokinase was associated with a reduction in both systolic and diastolic BP. The reduction in systolic BP was seen for both sexes but was more robust in males consuming nattokinase. The average reduction in diastolic BP in the nattokinase group from 87 mmHg to 84 mmHg was statistically significant when compared to that in the group consuming placebo, where the average diastolic BP remained constant at 87 mmHg (P<0.05, and reached a high level of significance for males consuming nattokinase, where the average diastolic BP dropped from 86 mmHg to 81 mmHg (P<0.006. A decrease in vWF was seen in the female population consuming nattokinase (P<0.1. In the subpopulation with low plasma renin activity levels at baseline (<0.29 ng/mL/h, an increase was seen for 66% of the people after 8-week consumption of nattokinase (P

  5. The metal-ion-dependent adhesion site in the Von Willebrand factor-A domain of α2δ subunits is key to trafficking voltage-gated Ca2+ channels

    Science.gov (United States)

    Cantí, C.; Nieto-Rostro, M.; Foucault, I.; Heblich, F.; Wratten, J.; Richards, M. W.; Hendrich, J.; Douglas, L.; Page, K. M.; Davies, A.; Dolphin, A. C.

    2005-01-01

    All auxiliary α2δ subunits of voltage-gated Ca2+ (CaV) channels contain an extracellular Von Willebrand factor-A (VWA) domain that, in α2δ-1 and -2, has a perfect metal-ion-dependent adhesion site (MIDAS). Modeling of the α2δ-2 VWA domain shows it to be highly likely to bind a divalent cation. Mutating the three key MIDAS residues responsible for divalent cation binding resulted in a MIDAS mutant α2δ-2 subunit that was still processed and trafficked normally when it was expressed alone. However, unlike WT α2δ-2, the MIDAS mutant α2δ-2 subunit did not enhance and, in some cases, further diminished CaV1.2, -2.1, and -2.2 currents coexpressed with β1b by using either Ba2+ or Na+ as a permeant ion. Furthermore, expression of the MIDAS mutant α2δ-2 reduced surface expression and strongly increased the perinuclear retention of CaVα1 subunits at the earliest time at which expression was observed in both Cos-7 and NG108–15 cells. Despite the presence of endogenous α2δ subunits, heterologous expression of α2δ-2 in differentiated NG108–15 cells further enhanced the endogenous high-threshold Ca2+ currents, whereas this enhancement was prevented by the MIDAS mutations. Our results indicate that α2δ subunits normally interact with the CaVα1 subunit early in their maturation, before the appearance of functional plasma membrane channels, and an intact MIDAS motif in the α2δ subunit is required to promote trafficking of the α1 subunit to the plasma membrane by an integrin-like switch. This finding provides evidence for a primary role of a VWA domain in intracellular trafficking of a multimeric complex, in contrast to the more usual roles in binding extracellular ligands in other exofacial VWA domains. PMID:16061813

  6. Expressão imunoistoquímica da endoglina (CD105 e do fator de von Willebrand em carcinoma epidermoide oral e sua relação com parâmetros clinicopatológicos

    Directory of Open Access Journals (Sweden)

    Rodrigo Porpino Mafra

    2016-03-01

    Full Text Available Resumo Contexto A angiogênese tem sido associada à progressão de neoplasias malignas e, embora haja estudos acerca de marcadores angiogênicos no carcinoma epidermoide oral (CEO, existem resultados conflitantes na literatura. Objetivos Avaliar a expressão imunoistoquímica do CD105 e do fator de von Willebrand (FvW em CEO e sua relação com parâmetros clínicos do tumor. Métodos A imunoexpressão dos referidos biomarcadores foi analisada em 30 casos de CEO e correlacionada a parâmetros clínicos do tumor (idade e sexo dos pacientes, localização anatômica e estadiamento clínico Tumor, Nodo e Metástase, TNM. Resultados A imunomarcação com o anticorpo anti-FvW foi mais efetiva que a do CD105 no CEO. No que concerne à localização anatômica, o assoalho bucal e a região retromolar apresentaram diferenças estatisticamente significativas quanto aos índices angiogênicos (p = 0,004, determinados pela técnica de contagem microvascular (MVC. Não houve relação estatisticamente significativa entre o estadiamento clínico TNM e os índices angiogênicos, com os dois biomarcadores. Conclusões Com base nos achados deste estudo, sugere-se um envolvimento da neoformação vascular na carcinogênese oral, embora não tenha sido evidenciada associação significativa com o estágio clínico da lesão.

  7. Consumption of nattokinase is associated with reduced blood pressure and von Willebrand factor, a cardiovascular risk marker: results from a randomized, double-blind, placebo-controlled, multicenter North American clinical trial.

    Science.gov (United States)

    Jensen, Gitte S; Lenninger, Miki; Ero, Michael P; Benson, Kathleen F

    2016-01-01

    The objective of this study is to evaluate the effects of consumption of nattokinase on hypertension in a North American hypertensive population with associated genetic, dietary, and lifestyle factors. This is in extension of, and contrast to, previous studies on Asian populations. A randomized, double-blind, placebo-controlled, parallel-arm clinical study was performed to evaluate nattokinase (NSK-SD), a fermented soy extract nattō from which vitamin K2 has been removed. Based on the results from previous studies on Asian populations, 79 subjects were enrolled upon screening for elevated blood pressure (BP; systolic BP ≥130 or diastolic BP ≥90 mmHg) who consumed placebo or 100 mg nattokinase/d for the 8-week study duration. Blood collections were performed at baseline and 8 weeks for testing plasma renin activity, von Willebrand factor (vWF), and platelet factor-4. Seventy-four people completed the study with good compliance. Consumption of nattokinase was associated with a reduction in both systolic and diastolic BP. The reduction in systolic BP was seen for both sexes but was more robust in males consuming nattokinase. The average reduction in diastolic BP in the nattokinase group from 87 mmHg to 84 mmHg was statistically significant when compared to that in the group consuming placebo, where the average diastolic BP remained constant at 87 mmHg ( P nattokinase, where the average diastolic BP dropped from 86 mmHg to 81 mmHg ( P nattokinase ( P nattokinase ( P nattokinase consumption in a North American population is associated with beneficial changes to BP in a hypertensive population, indicating sex-specific mechanisms of action of nattokinase's effect on vWF and hypertension.

  8. Genetics Home Reference: von Willebrand disease

    Science.gov (United States)

    ... mildest and most common of the three types, accounting for 75 percent of affected individuals. Type 3 ... diseases that affect bone marrow or immune cell function. This rare form of the condition is characterized ...

  9. Erythrocytes and von Willebrand factor in venous thrombosis

    NARCIS (Netherlands)

    Smeets, M.W.J.

    2018-01-01

    Venous thromboembolism represents the third leading vascular disease after myocardial infarction and stroke. Erythrocytes, the most abundant cells in venous thrombi, were thought to be innocent bystanders that become tangled up in the fibrin mesh of venous thrombi. However, this thesis describes

  10. Von Willebrand's disease: case report and review of literature ...

    African Journals Online (AJOL)

    By taking a clinical history of bleeding (mucocutaneous bleeding symptoms suggestive of a primary haemostatic disorder, a quantitative or qualitative abnormality of VWF is possible) it is important to think about VWD and to make the appropriate diagnosis. If the VWD is suspected diagnostic tests should include an activated ...

  11. Patient with von Willebrand Disease for Gynaecologic Surgery - Perianaesthetic Concerns

    Directory of Open Access Journals (Sweden)

    Rakesh Garg

    2008-01-01

    Patients with vWD do not carry an increased operative risk during elective procedures if appropriate prophylac-tic and corrective therapy is administered. Although the administration of cryoprecipitate and other blood products has traditionally been the cornerstone of treatment for vWD, the recent development of desmopressin(DDAVP for clinical use may provide an effective alternative to replacement therapy with blood products. Further laparaoscopic procedures, taking care during ryle′s tube and foley′s catheter insertion, in such patients are the safer alternative for all kind of gynecologic surgeries.

  12. Molecular characterization of exon 28 of von Willebrand's factor ...

    African Journals Online (AJOL)

    2016-05-12

    May 12, 2016 ... were mostly among individuals with Arab ancestry.[3] In. Zimbabwe ... bleeding symptoms are epistaxis, menorrhagia (in women), easy bruising, oral cavity ... North American, British, and Japanese populations. rs1800383 ...

  13. Clinical Significance of von Willebrand Factor and Antithrombin in Diabetes Mellitus with Retinopathy%血管性血友病因子与抗凝血酶在糖尿病视网膜病变中的临床意义

    Institute of Scientific and Technical Information of China (English)

    张鹏; 汤荣华

    2012-01-01

    目的 探讨糖尿病微血管视网膜病变患者血管性血友病因子(vWF)、抗凝血酶(AT)的变化及临床意义.方法 将100例2型糖尿病患者分为两组,糖尿病无微血管视网膜病变并发症组53例,糖尿病微血管视网膜病变并发症组47例,设健康人群对照组50例.所有人群入院或体检时即采集静脉血,进行vWF:Ag、AT:A检测.结果 2型糖尿病无微血管视网膜病变并发症组患者血浆vWF:Ag含量较正常对照组增高(P<0.05),2型糖尿病微血管视网膜病变并发症组患者血浆vWF:Ag含量与2型糖尿病无微血管视网膜病变并发症组及正常对照组相比有显著性差异(P<0.05);且2型糖尿病微血管视网膜病变并发症组中背景性病变和增殖性病变患者血浆vWF:Ag含量比较有显著性差异(P<0.05).2型糖尿病无微血管视网膜病变并发症组患者血浆AT活性与正常对照组相比无显著性差异(P>0.05),2型糖尿病微血管视网膜病变并发症组患者血浆AT活性与2型糖尿病无微血管视网膜病变并发症组及正常对照组相比有显著性差异(P<0.05);且2型糖尿病微血管视网膜病变并发症组中背景性病变和增殖性病变患者血浆AT活性比较有显著性差异(P<0.05).结论 血浆vWF:Ag、AT:A的变化与糖尿病微血管视网膜病变的发生、发展有密切关系,监测其水平与活性对糖尿病微血管并发症的治疗和预防有重要的临床意义.%Objective To explore the changes of von Willebrand factor(vWF) and antithrombin(AT) in diabetic patients with retinopathy and its clinical implications. Methods 100 type 2 diabetes mellitus (T2DM) patients were divided into 2 groups,one group included 53 T2DM patients without retinopathy,another group included 47 T2DM patients with retinopathy, 50 healthy peoples were enrolled as control group. Venous blood was collected from all groups and vWF:Ag, AT; A were determined. Results The level of vWF;Ag in T2DM

  14. Rapid method to predict the storage stability of middle distillates; Schnelltest zur Vorhersage der Lagerstabilitaet von Mitteldestillaten

    Energy Technology Data Exchange (ETDEWEB)

    Depta, H.; Wehn, R. [RWE - Gesellschaft fuer Forschung und Entwicklung mbH, Wesseling (Germany); Kohlmeyer, U. [Deutsche Shell AG, Hamburg (Germany)

    1998-12-01

    In the literature, various quick tests to predict the ageing stability of middle distillates are described. 59 gasoil components and finished products were tested, using methods recommended by a detailed literature study DGMK-Report 484, namely: - the colorimetric/spectrophotometric method according to R.K. Solly and S.J. Marshman, - the quantification of Soluble Macromolecular Oxidatively Reactive Species (SMORS) according to M.A. Wechter and D.R. Hardy, - the determination of phenalene and phenalenone as well as non-basic nitrogenous aromatics. ASTM D 4625-92 was used as a reference test (storage at 43 C over a period of 12 weeks, with air contact). The results obtained showed that none of the methods mentioned above are suitable as a reliable quick test, because the regression analysis shows no acceptable correlation between the data obtained and the insolubles derived from the reference test. The hypothesis of Pedley et al., referring to the ageing mechanism of middle distillates, could not be confirmed. The spectrophotometric method gives the best result, considering the total nitrogen content. The accuracy of the prediction of ASTM-Test results is about 75%. The additionally carried out `Rancimat-Test` does not correlate at all with the insolubles based on ASTM D 4625-92. The insolubles as determined according to ASTM D 4625 neither do correlate with the amount of sediments which are formed after one year`s storage under genuine conditions. On the other hand, the supplementarily conducted `Shell Window Test` allows a prediction of the longterm storage behaviour with a likelihood of 78% which is expected to improve after a revision of the method with regard to reproducible test conditions. (orig.) [Deutsch] In der Literatur werden verschiedene Schnelltests zur Vorhersage der Alterungsstabilitaet von Mitteldestillaten beschrieben. An 59 Gasoel-Komponenten und -Fertigprodukten wurden die in der Literaturrecherche DGMK-Bericht 484 empfohlenen Methoden ueberprueft

  15. Predicting suitable optoelectronic properties of monoclinic VON semiconductor crystals for photovoltaics using accurate first-principles computations

    KAUST Repository

    Harb, Moussab

    2015-01-01

    Using accurate first-principles quantum calculations based on DFT (including the perturbation theory DFPT) with the range-separated hybrid HSE06 exchange-correlation functional, we predict essential fundamental properties (such as bandgap, optical absorption coefficient, dielectric constant, charge carrier effective masses and exciton binding energy) of two stable monoclinic vanadium oxynitride (VON) semiconductor crystals for solar energy conversion applications. In addition to the predicted band gaps in the optimal range for making single-junction solar cells, both polymorphs exhibit relatively high absorption efficiencies in the visible range, high dielectric constants, high charge carrier mobilities and much lower exciton binding energies than the thermal energy at room temperature. Moreover, their optical absorption, dielectric and exciton dissociation properties are found to be better than those obtained for semiconductors frequently utilized in photovoltaic devices like Si, CdTe and GaAs. These novel results offer a great opportunity for this stoichiometric VON material to be properly synthesized and considered as a new good candidate for photovoltaic applications.

  16. Predicting suitable optoelectronic properties of monoclinic VON semiconductor crystals for photovoltaics using accurate first-principles computations

    KAUST Repository

    Harb, Moussab

    2015-08-26

    Using accurate first-principles quantum calculations based on DFT (including the perturbation theory DFPT) with the range-separated hybrid HSE06 exchange-correlation functional, we predict essential fundamental properties (such as bandgap, optical absorption coefficient, dielectric constant, charge carrier effective masses and exciton binding energy) of two stable monoclinic vanadium oxynitride (VON) semiconductor crystals for solar energy conversion applications. In addition to the predicted band gaps in the optimal range for making single-junction solar cells, both polymorphs exhibit relatively high absorption efficiencies in the visible range, high dielectric constants, high charge carrier mobilities and much lower exciton binding energies than the thermal energy at room temperature. Moreover, their optical absorption, dielectric and exciton dissociation properties are found to be better than those obtained for semiconductors frequently utilized in photovoltaic devices like Si, CdTe and GaAs. These novel results offer a great opportunity for this stoichiometric VON material to be properly synthesized and considered as a new good candidate for photovoltaic applications.

  17. Models for settlement prediction of structures in opencast dumps; Modelle zur Setzungsprognose von Bauwerken auf Tagebaukippen

    Energy Technology Data Exchange (ETDEWEB)

    Birle, E.; Vogt, S. [Technische Univ. Muenchen (Germany). Zentrum Geotechnik

    2016-05-01

    For construction projects at opencast dumps e.g. for planning of traffic routes or individual buildings a prognosis of dump subsicence after the establishment of the structures is required. It should be noted that on dump surfaces time-dependent subsidence are observed which can change by construction activities at the dump surface. As tools for describing the dump subsidence phenomenological models that have been developed based on the evaluation of dump characteristic subsidence and allow a one-dimensional analysis of creep deformation and visco-elastoplastic material models within the finite element method for analyzing complex geometric boundary conditions. [German] Fuer Baumassnahmen auf Tagebaukippen beispielsweise zur Planung von Verkehrswegen oder einzelnen Bauwerken ist eine Prognose der Kippensetzungen nach Errichtung der Bauwerke erforderlich. Dabei ist zu beachten, dass auf Kippenoberflaechen ausgepraegte zeitabhaengige Setzungen beobachtet werden, die sich durch Baumassnahmen an der Kippenoberflaeche aendern koennen. Als Werkzeuge zur Beschreibung der Kippensetzungen stehen prinzipiell phaenomenologische Modelle, die auf Basis der Auswertung von Kippeneigensetzungen entwickelt wurden und die eine ein-dimensionale Analyse der Kriechverformungen zulassen sowie visko-elastoplastische Stoffmodelle im Rahmen der FiniteElemente- Methode zur Analyse komplexer geometrischer Randbedingungen zur Verfuegung. In Abhaengigkeit vom Randwertproblem ist zu entscheiden, welches der Modelle zur Beschreibung der Kippensetzungen heranzuziehen ist. Mit phaenomenologischen Kriechmodellen und einer ein-dimensionalen Analyse der Verformungen koennen die sich nach Ende der Verkippung einstellenden Kippensetzungen in der Regel genuegend genau beschrieben werden, sofern an der Kippenoberflaeche keine signifikanten Spannungsaenderungen infolge von Baumassnahmen eingetragen werden. Kommt es dagegen zu Spannungsaenderungen, beispielsweise durch die Errichtung eines hohen

  18. Acquired Von Willebrand’s Syndrome in Systemic Lupus Erythematosus

    Directory of Open Access Journals (Sweden)

    Sara Taveras Alam

    2014-01-01

    Full Text Available Acquired von Willebrand syndrome (AVWS is an uncommon, underdiagnosed, and heterogeneous disease which is increasingly recognized as a cause of bleeding diatheses. Systemic lupus erythematosus (SLE is an infrequent cause of AVWS. Herein, we report a case of AVWS diagnosed during the initial presentation of SLE in a previously healthy young man with no family history of bleeding diathesis who presented with worsening epistaxis, gastrointestinal bleeding, and anasarca. He was found to have severe anemia and prolonged activated partial thromboplastin time (aPTT with severely decreased levels of von Willebrand factor (VWF measurements in addition to markedly decreased factor VIII levels. Further evaluation revealed nephrotic syndrome and interstitial lung disease due to SLE. He initially received combination therapy with intravenous immunoglobulin (IVIG and von Willebrand factor/factor VIII concentrates without significant improvement. Treatment with steroids, cyclophosphamide, and rituximab was followed by clinical improvement evidenced by cessation of bleeding. The short follow-up did not allow us to definitely prove the therapeutic effect of immunosuppressive treatment on AVWS in SLE patients. This case adds to the literature supporting the relationship between AVWS and SLE and highlights the importance of combination therapy in the treatment of severe AVWS as well as the role of IVIG, cyclophosphamide, and rituximab in AVWS associated with SLE.

  19. Protéolyse du facteur Willebrand et cardiopathies à forces de cisaillement élevées : nouvelles approches diagnostiques et thérapeutiques

    OpenAIRE

    Rauch , Antoine

    2014-01-01

    In the first part of the thesis, we describe a novel approach based on antibody-based therapy to prevent the acquired von Willebrand factor (VWF) degradation observed in continuous-flow mechanical circulatory assist device therapy. Via a murine monoclonal antibody directed against VWF D4 domain and thus interfering with VWF-ADAMTS13 binding, a partial inhibition of VWF degradation is observed in whole blood using an ex vivo circulatory assist device model. In the second part of the thesis, we...

  20. Predicting the durability of mineral external plaster using accelerated ageing tests; Prognose der Dauerhaftigkeit mineralischer Aussenputze mit Hilfe von beschleunigten Alterungstests

    Energy Technology Data Exchange (ETDEWEB)

    Bochen, Jerzy; Nowak, Henryk A. [Schlesische Technische Universitaet, Lehrstuhl Bauprozesse, Gliwice (Poland)

    2004-08-01

    This article presents a technique for accelerated ageing tests for different plasters. Two models were developed for describing the durability. The models describe changes in selected characteristics due to frost damage and leaching. The first model is based on changes in mass, the second on changes in strength. The models consider the main characteristics that influence durability, such as strength, porosity, permeability, adhesive tensil strength and aggressive environmental influences. Both models enable the durability of external plaster to be predicted. (Abstract Copyright [2004], Wiley Periodicals, Inc.) [German] Der Beitrag stellt eine Methode fuer beschleunigte Alterungstests von verschiedenen Putzen vor. Fuer die Beschreibung der Dauerhaftigkeit wurden zwei Modelle entwickelt. Die Modelle beschreiben Veraenderungen ausgewaehlter Eigenschaften, die infolge von Frostschaeden und Auslaugung auftreten. Das erste Modell basiert auf der Veraenderung der Masse und das zweite auf der Veraenderung der Festigkeit. In den Modellen werden die wesentlichen Eigenschaften beruecksichtigt, die die Dauerhaftigkeit beeinflussen, wie z. B. Festigkeit, Porositaet, Dichtigkeit, Haftzugfestigkeit und agressive Umwelteinwirkungen. Beide Modelle ermoeglichen die Prognose der Dauerhaftigkeit von Aussenputzen. (Abstract Copyright [2004], Wiley Periodicals, Inc.)

  1. Factor VIII and von Willebrand factor co-delivery by endothelial cells

    NARCIS (Netherlands)

    Bouwens, E.A.M.|info:eu-repo/dai/nl/314061894

    2011-01-01

    A defect in coagulation factor VIII (FVIII) results in the inherited bleeding disorder hemophilia A. Current treatment of hemophilia A is hampered by the need of frequent administration of costly FVIII products. Therefore gene therapy is an attractive alternative for protein replacement to treat

  2. Exercise induced hypercoagulability, increased von Willebrand factor and decreased thyroid hormone concentrations in sled dogs

    DEFF Research Database (Denmark)

    Krogh, Anne Kirstine Havnsøe; Legind, Pernille; Kjelgaard-Hansen, Mads

    2014-01-01

    Sled dogs performing endurance races have been reported to have a high incidence of gastric erosions or ulcerations and an increased risk of gastro intestinal bleeding leading to death in some cases. In addition, these dogs also become hypothyroid during training and exercise. Canine hypothyroidi...

  3. Mutation analysis and clinical implications of von Willebrand factor-cleaving protease deficiency.

    NARCIS (Netherlands)

    Assink, K.F.H.; Schiphorst, R.H.M.; Allford, S.; Karpman, D.; Etzioni, A.; Brichard, B.; Kar, N.C.A.J. van de; Monnens, L.A.H.; Heuvel, L.P.W.J. van den

    2003-01-01

    BACKGROUND: The pentad of thrombocytopenia, hemolytic anemia, mild renal dysfunction, neurologic signs, and fever, classically characterizes the syndrome of thrombotic thrombocytopenic purpura (TTP). TTP usually occurs in adults as an acquired form but a congenital form in children has also been

  4. Bleeding score in Type 1 von Willebrand disease patients using the ISTH-BAT questionnaire.

    Science.gov (United States)

    Pathare, A; Al Omrani, S; Al Hajri, F; Al Obaidani, N; Al Balushi, B; Al Falahi, K

    2018-04-01

    Bleeding assessment tools have evolved in the last decade to standardize the assessment of the severity of bleeding symptom in a consistent way. In 2010, the International Society on Thrombosis and Hemostasis-Bleeding Assessment Tool (ISTH-BAT) was developed and validated. Our aim was to administer ISTH-BAT questionnaire to the Omani patients with type 1 VWD and obtain the bleeding score (BS). We also studied the severity of their bleeding symptoms and correlated it with the BS as well as with the laboratory parameters. Forty-eight type I VWD index cases and 52 normal subjects were interviewed and the ISTH-BAT questionnaire administered. The BS was calculated based on a history of bleeding symptoms from 12 different sites according to the standard ISTH-BAT questionnaire. Laboratory parameters were obtained from patient's medical records. The mean age of this cohort was 27 years (range, 6-49) with 60% being females. The median time to administer this questionnaire was 10 minutes with an interquartile range (IQR) from 8 to 17 minutes. Overall, the median BS was 7 (IQR; 2,11) although individual scores ranged between 0 and 36. The BS was negatively correlated with VWF: Ag, VWF: RCo, and VWF: CB and the Spearman's correlation coefficient "rho" was, respectively, -0.15, -0.08, and -0.22. The ISTH-BAT BS is designed to reflect the severity of bleeding. Our results demonstrate the inherent variability of this bleeding pattern. We also found that the ISTH-BAT BS significantly correlated with VWF: Ag and VWF: CB. © 2017 John Wiley & Sons Ltd.

  5. Nitric oxide level and von Willebrand factor (vWF) secretion are not ...

    African Journals Online (AJOL)

    Jane

    2011-08-15

    Aug 15, 2011 ... potassium channels; RBECs, rat brain capillary endothelial cells. and transport of ... addition, adenine nucleotides modulate the release of endothelial-derive ..... A cellular model of endothelial cell ischemia. J Surg Res. 44(5): ...

  6. Structural studies on B2-glycoprotein I and von Willebrand factor A3 domain

    NARCIS (Netherlands)

    Bouma, B.

    2000-01-01

    The integrity of blood circulation is a prerequisite for life; its malfunctioning is a leading cause of morbidity and mortality in developed countries. For that reason the haemostatic system is a critical component of homeostasis. In Chapter I an overview is given of the biophysical and biochemical

  7. von Neumann Morgenstern Preferences

    DEFF Research Database (Denmark)

    Vind, Karl

    von Neumann Morgenstern utility is generalized to von Neumann Morgenstern preferences. The proof is an application of simple hyperplane theorems......von Neumann Morgenstern utility is generalized to von Neumann Morgenstern preferences. The proof is an application of simple hyperplane theorems...

  8. von Neumann Morgenstern Preferences

    DEFF Research Database (Denmark)

    Vind, Karl

    2000-01-01

    von Neumann Morgenstern utility is generalized to von Neumann Morgenstern preferences. The proof is an application of simple hyperplane theorems......von Neumann Morgenstern utility is generalized to von Neumann Morgenstern preferences. The proof is an application of simple hyperplane theorems...

  9. JST Thesaurus Headwords and Synonyms: von Willebrand病 [MeCab user dictionary for science technology term[Archive

    Lifescience Database Archive (English)

    Full Text Available MeCab user dictionary for science technology term von Willebrand病 名詞 一般 * * * * von... Willebrand病 von Willebrandビョウ ブイオーエヌ ダブリューアイエルエルイービーアールエイエヌディービョー Thesaurus2015 200906053707829497 C LS51 UNKNOWN_2 von Willebrand

  10. JST Thesaurus Headwords and Synonyms: Von Willebrand病 [MeCab user dictionary for science technology term[Archive

    Lifescience Database Archive (English)

    Full Text Available MeCab user dictionary for science technology term Von Willebrand病 名詞 一般 * * * * von... Willebrand病 von Willebrandビョウ ブイオーエヌ ダブリューアイエルエルイービーアールエイエヌディービョー Thesaurus2015 200906053707829497 C LS51 UNKNOWN_2 Von Willebrand

  11. JST Thesaurus Headwords and Synonyms: von Willebrand因子 [MeCab user dictionary for science technology term[Archive

    Lifescience Database Archive (English)

    Full Text Available MeCab user dictionary for science technology term von Willebrand因子 名詞 一般 * * * * vo...n Willebrand因子 von Willebrandインシ ブイオーエヌ ダブリューアイエルエルイービーアールエイエヌディーインシ Thesaurus2015 200906033515671406 C LS15/LS33 UNKNOWN_2 von Willebrand 因子

  12. Molecular modelling of the Norrie disease protein predicts a cystine knot growth factor tertiary structure.

    Science.gov (United States)

    Meitinger, T; Meindl, A; Bork, P; Rost, B; Sander, C; Haasemann, M; Murken, J

    1993-12-01

    The X-lined gene for Norrie disease, which is characterized by blindness, deafness and mental retardation has been cloned recently. This gene has been thought to code for a putative extracellular factor; its predicted amino acid sequence is homologous to the C-terminal domain of diverse extracellular proteins. Sequence pattern searches and three-dimensional modelling now suggest that the Norrie disease protein (NDP) has a tertiary structure similar to that of transforming growth factor beta (TGF beta). Our model identifies NDP as a member of an emerging family of growth factors containing a cystine knot motif, with direct implications for the physiological role of NDP. The model also sheds light on sequence related domains such as the C-terminal domain of mucins and of von Willebrand factor.

  13. COMPARISON ON ACCURACY OF LOGISTIC, GOMPERTZ AND VON BERTALANFFY MODELS IN PREDICTING GROWTH OF NEW BORN CALF UNTIL FIRST MATING OF HOLSTEIN FRIESIAN HEIFERS

    Directory of Open Access Journals (Sweden)

    L. Budimulyati S.

    2014-10-01

    Full Text Available The body weight records of 1221 heifers were used in this study collected from PT Taurus DairyFarm Sukabumi from year 2001 until 2011. The records that could be used for analysis were 373 out of1221 heifers, having completed data from birth to first mating period. Three different models i.e,Logistic, Gompertz, and von Bertalanffy were performed to analyze the growth rate of heifers. Theresults showed that the three models had different accuracy and heavily depend on age, environment andduration of recording. The body weights of sexual maturity and on certain ages were affected by theduration of recording. The Gompertz model was performed as the simpliest model in form ofcalculation. On the other hand, the Logistic was more difficult to calculate. All models indicated highaccuracy with the determination coefficient (R2 more than 90%. Based on the comparison, theGompertz and Logistic model are recommended for predicting the growth rate of heifers from birth tosexual maturity.

  14. Service life prediction. Development of models for predicting the service life of power plant components subject to thermomechanical creep fatigue; Lebensdauervorhersage. Entwicklung von Modellen zur Lebensdauervorhersage von Kraftwerksbauteilen unter thermisch-mechanischer Kriechermuedungsbeanspruchung. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Cui, L.; Scholz, A. [Technische Univ. Darmstadt (Germany). Institut fuer Werkstoffkunde; Hartrott, P. von; Schlesinger, M. [Fraunhofer-Institut fuer Werkstoffmechanik (IWM), Freiburg im Breisgau (Germany)

    2009-07-01

    Extensive use is made of massive components of heat resistant and highly heat resistant materials in installations of the power and heating industry. These components are exposed to varying thermomechanical stress as a result of ramping-up and down processes. In this research project two computer-assisted methods of predicting service life until crack initiation were extended to include cases of thermomechanical multi-axis stress conducive to creep fatigue and of superposition of high-cycle stress on power plant components. Investigations were limited to rotor steel of type X12CrMoWVNbN10-1-1. Complex thermomechanical multi-axis experiments were performed on round, notched and cruciform test specimens of close-to-life dimensions in order to demonstrate by experiment the validity of these models. The results of these calculations showed an acceptable degree of agreement between experiment and simulation for both models. Calculations on earlier TMF experiments performed at IfW on hollow specimens of 1%CrMoNiV showed good predictability for both the SARA and the ThoMat programme. Calculations on experiments performed at MPA Stuttgart on model bodies consisting of the same 1%CrMoNiV showed a predictability of acceptable variability considering the complexity of the stresses involved. A further outcome of this project is that the use of SARA appears universally suitable for the construction of new plants and in the service area, while the use of ThoMat appears suited for detail optimisation in the development process.

  15. JST Thesaurus Headwords and Synonyms: Von Willebrand症候群 [MeCab user dictionary for science technology term[Archive

    Lifescience Database Archive (English)

    Full Text Available MeCab user dictionary for science technology term Von Willebrand症候群 名詞 一般 * * * * v...on Willebrand病 von Willebrandビョウ ブイオーエヌ ダブリューアイエルエルイービーアールエイエヌディービョー Thesaurus2015 200906053707829497 C LS51 UNKNOWN_2 Von Willebrand 症候群

  16. JST Thesaurus Headwords and Synonyms: Von Willebrand因子欠乏 [MeCab user dictionary for science technology term[Archive

    Lifescience Database Archive (English)

    Full Text Available MeCab user dictionary for science technology term Von Willebrand因子欠乏 名詞 サ変接続 * * * ...* von Willebrand病 von Willebrandビョウ ブイオーエヌ ダブリューアイエルエルイービーアールエイエヌディービョー Thesaurus2015 200906053707829497 C LS51 UNKNOWN_2 Von Willebrand 因子 欠乏

  17. 可吸收镁合金支架植入后犬冠状动脉C-反应蛋白、基质金属蛋白酶9和血管性血友病因子的表达%Effect of absorbable magnesium alloy stenting on expression of C-reactive protein, matrix metalloproteinase-9 and von Willebrand factor in dogs

    Institute of Scientific and Technical Information of China (English)

    王汝朋; 杨水祥

    2015-01-01

    BACKGROUND:Our previous study have verified the biosafety of absorbable magnesium aloy stents from a macro perspective. OBJECTIVE:To study the expressions of C-reactive protein, matrix metaloproteinase-9 and von Wilebrand factor in local vascular tissue after magnesium aloy stenting, and to explore the histocompatibility and safety of magnesium aloy stents at the molecular expression level. METHODS:Twenty-five absorbable magnesium aloy stents were implanted into the left anterior descending artery or circumflex artery of 25 epidemic prevention mongrel dogs. Five dogs with no stenting served as control group. Five dogs were sacrificed respectively at 24 hours, 3 days, 5 days, 1 week, 1 month after stenting, and vascular specimens were taken for preparation of pathological sections. The expressions of C-reactive protein, matrix metaloproteinase-9 and von Wilebrand factor within the coronary artery wal were determined by immunohistochemical staining method. RESULTS AND CONCLUSION: Compared with the control group, the number of cels positive for C-reactive protein, matrix metaloproteinase-9 and von Wilebrand factor was significantly increased at different times after stenting (P 0.01). The inflammatory reactions induced by absorbable magnesium aloy stents are slight and last for short time, which suggests that the absorbable magnesium aloy stents have good histocompatibility and safety.%背景:课题组前期研究从宏观角度验证了可吸收镁合金支架的生物安全性。目的:观察可吸收镁合金支架植入后局部血管组织C-反应蛋白、基质金属蛋白酶9及血管性血友病因子的表达情况,从分子表达水平深层次探讨镁合金支架的组织相容性及安全性。方法:将25枚可吸收镁合金支架植入25只防疫杂种犬冠状动脉前降支或左回旋支,未植入支架的5只犬冠状动脉作为正常对照组,支架植入后24 h、3 d、5 d、1周、1个月各处死动物5只,取支架植入后的

  18. Ellis Von Creveld Syndrome

    Directory of Open Access Journals (Sweden)

    Afshar H

    1999-01-01

    Full Text Available One patient with Ellis Von Creveld syndrome contains: dwarfism, congenital heart"ndisease, ectodermal dysplasia, polyductyly, an abnormally wide labial frenum and maxillary"nmolars with single root.

  19. Lars von Triers film

    DEFF Research Database (Denmark)

    Nielsen, Lisbeth Overgaard

    2007-01-01

    Afhandlingen undersøger Lars von Triers filmæstetik, som den kommer til udtryk i spillefilmene fra perioden 1984-2007. Afhandlingen analyserer de enkelte films stil, virkningsstrategi og betydningsdannelse.......Afhandlingen undersøger Lars von Triers filmæstetik, som den kommer til udtryk i spillefilmene fra perioden 1984-2007. Afhandlingen analyserer de enkelte films stil, virkningsstrategi og betydningsdannelse....

  20. Data on the purification and crystallization of the loss-of-function von Willebrand disease variant (p.Gly1324Ser of the von Willebrand factor A1 domain

    Directory of Open Access Journals (Sweden)

    James C. Cambell

    2016-06-01

    In this data article we describe the production, quality control and crystallization of the p.Gly1324Ser vWD variant of the A1 domain of VWF. p.Gly1324Ser A1 was expressed in Escherichia coli as insoluble inclusion bodies. After the preparation of the inclusion bodies, the protein was solubilized, refolded, purified by affinity chromatography and crystallized. The crystal structure of the p.Gly1324Ser mutant of the A1 domain is deposited at the Protein Data Bank PDB: 5BV8

  1. MARCKO thermal insulation layers. Life predictions for thermal insulation and antioxidant layers. Final report; MARCKO-Waermedaemmschichten. Methoden zur Lebensdauervorhersage von Waermedaemm- und Oxidationsschutzschichten. Schlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Schuetze, M.

    2003-07-01

    , Rolls-Royce und Siemens als Industriepartner und FZ-Juelich, DLR und DECHEMA als Institute beteiligt waren, wurden Arbeiten zur Entwicklung eines Lebensdauermodells fuer einkristalline, keramisch beschichtete Gasturbinenschaufeln durchgefuehrt. Dieses Modell soll zuverlaessige Voraussagen ueber die Zeitdauer der Haltbarkeit der Keramik und der Haftvermittlerschicht unter verschiedenen Betriebsbedingungen ermoeglichen. Die Aufgabe des Karl-Winnacker-Instituts der DECHEMA e.V. im Rahmen dieses Verbundprojektes bestand zunaechst in isothermen Oxidationsversuchen, die bei 950 C-1100 C an Laborluft durchgefuehrt wurden. Anschliessend wurde das Oxidationsverhalten anhand von metallographischen Schliffen charakterisiert. Dabei wurde besonderes Augenmerk auf die Entwicklung der TGO (Thermally Grown Oxide)-Schichtdicken, der oxidschichtseitigen Aluminiumverarmung im Bond Coat sowie der physikalischen Defekte in Form von Poren, Porenpopulationen und Mikrorissen innerhalb bzw. in unmittelbarer Naehe der TGO gelegt. Erstmalig wurden diese Mikrorisse postexperimentell anhand von rasterelektronenmikroskopischen Aufnahmen klassifiziert und die maximalen Abmessungen solcher Risse in Abhaengigkeit der Auslagerungsdauer quantifiziert. Fuer alle diese Parameter wurden Kinetiken ermittelt. Weiterhin wurden wachstumsinduzierte, laterale Spannungen in der TGO anhand der Durchbiegung einer duennen Metallfolie aus reinem Bond Coat Material bestimmt. Im Rahmen eines Unterauftrags von Projektpartner Rolls-Royce wurde das mechanische Verhalten APS-gespritzter Waermedaemmschichten mittels uniaxialer Druckversuche an freistehenden, hohlzylindrischen Ringproben anwendungstypischer Dicke bei Raum- und Anwendungstemperatur untersucht. Einerseits wurde das thermoelastische Verhalten mittels weggeregelter, zyklischer Belastungsversuche ermittelt, andererseits wurde das thermoplastische Verhalten anhand von lastgeregelten Kriechexperimenten bestimmt. Um den Einfluss einer vorhergehenden

  2. Ultralarge von Willebrand Factor Fibers Mediate Luminal Staphylococcus aureus Adhesion to an Intact Endothelial Cell Layer Under Shear Stress

    NARCIS (Netherlands)

    Pappelbaum, Karin I.; Gorzelanny, Christian; Graessle, Sandra; Suckau, Jan; Laschke, Matthias W.; Bischoff, Markus; Bauer, Corinne; Schorpp-Kistner, Marina; Weidenmaier, Christopher; Schneppenheim, Reinhard; Obser, Tobias; Sinha, Bhanu; Schneider, Stefan W.

    2013-01-01

    Background During pathogenesis of infective endocarditis, Staphylococcus aureus adherence often occurs without identifiable preexisting heart disease. However, molecular mechanisms mediating initial bacterial adhesion to morphologically intact endocardium are largely unknown. Methods and Results

  3. Von Willebrand disease and other bleeding disorders in women: consensus on diagnosis and management from an international expert panel

    NARCIS (Netherlands)

    James, Andra H.; Kouides, Peter A.; Abdul-Kadir, Rezan; Edlund, Mans; Federici, Augusto B.; Halimeh, Susan; Kamphuisen, Pieter W.; Konkle, Barbara A.; Martínez-Perez, Oscar; McLintock, Claire; Peyvandi, Flora; Winikoff, Rochelle

    2009-01-01

    Reproductive tract bleeding in women is a naturally occurring event during menstruation and childbirth. In women with menorrhagia, however, congenital bleeding disorders historically have been underdiagnosed. This consensus is intended to allow physicians to better recognize bleeding disorders as a

  4. Early intraoperative blood collection does not affect complete blood counts, von Willebrand factor or factor VIII levels in normal children.

    Science.gov (United States)

    Darwish, Hanni; Mundell, Gillianne; Engen, Dale; Lillicrap, David; Silva, Mariana; James, Paula

    2011-01-01

    Obtaining blood from children for research studies can be difficult, particularly for controls. One solution is to obtain samples during elective surgery; however, consideration must be given to the potential effects of the timing of phlebotomy. Ten children were recruited and phlebotomy was carried out during a preoperative clinic visit and intraoperatively immediately after the induction of anesthesia but before the start of surgery. CBCs, VWF, and FVIII levels were measured at both time points and no significant differences were seen. This negative result may be beneficial to pediatric research by suggesting that early intraoperative blood collection for controls does not affect the results.

  5. Enhancing the 'real world' prediction of cardiovascular events and major bleeding with the CHA2DS2-VASc and HAS-BLED scores using multiple biomarkers.

    Science.gov (United States)

    Roldán, Vanessa; Rivera-Caravaca, José Miguel; Shantsila, Alena; García-Fernández, Amaya; Esteve-Pastor, María Asunción; Vilchez, Juan Antonio; Romera, Marta; Valdés, Mariano; Vicente, Vicente; Marín, Francisco; Lip, Gregory Y H

    2018-02-01

    Atrial fibrillation (AF)-European guidelines suggest the use of biomarkers to stratify patients for stroke and bleeding risks. We investigated if a multibiomarker strategy improved the predictive performance of CHA 2 DS 2 -VASc and HAS-BLED in anticoagulated AF patients. We included consecutive patients stabilized for six months on vitamin K antagonists (INRs 2.0-3.0). High sensitivity troponin T, NT-proBNP, interleukin-6, von Willebrand factor concentrations and glomerular filtration rate (eGFR; using MDRD-4 formula) were quantified at baseline. Time in therapeutic range (TTR) was recorded at six months after inclusion. Patients were follow-up during a median of 2375 (IQR 1564-2887) days and all adverse events were recorded. In 1361 patients, adding four blood biomarkers, TTR and MDRD-eGFR, the predictive value of CHA 2 DS 2 -VASc increased significantly by c-index (0.63 vs. 0.65; p = .030) and IDI (0.85%; p originals scores. Addition of biomarkers enhanced the predictive value of CHA 2 DS 2 -VASc and HAS-BLED, although the overall improvement was modest and the added predictive advantage over original scores was marginal. Key Messages Recent atrial fibrillation (AF)-European guidelines for the first time suggest the use of biomarkers to stratify patients for stroke and bleeding risks, but their usefulness in real world for risk stratification is still questionable. In this cohort study involving 1361 AF patients optimally anticoagulated with vitamin K antagonists, adding high sensitivity troponin T, N-terminal pro-B-type natriuretic peptide, interleukin 6, von Willebrand factor, glomerular filtration rate (by the MDRD-4 formula) and time in therapeutic range, increased the predictive value of CHA 2 DS 2 -VASc for cardiovascular events, but not the predictive value of HAS-BLED for major bleeding. Reclassification analyses did not show improvement adding multiple biomarkers. Despite the improvement observed, the added predictive advantage is marginal and

  6. Rhizostomeen von Manila

    NARCIS (Netherlands)

    Stiasny, G.

    1924-01-01

    Die hier beschriebene kleine Scyphomedusen-Sammlung wurde von Herrn Director P. B. Sivickis, Dept. of Zoology, University of Philippines, Manila, dem Rijksmuseum van Natuurlijke Historie in Leiden überwiesen. Das Material wurde im December 1922 in Manila-bay gefischt und befindet sich in bestem

  7. Schmetterlinge von Madeira

    NARCIS (Netherlands)

    Martin, K.

    1941-01-01

    Wer auf einer ozeanischen Insel Schmetterlinge sammeln will, darf seine Erwartungen nicht zu hoch spannen; aber dennoch waren meine Frau und ich sehr enttäuscht, als uns auf einer Reise nach Madeira von einer dort angesessenen, gebildeten Dame gesagt wurde, sie habe auf der Insel niemals einen

  8. Biologischer Anbau von Strauchbeeren

    OpenAIRE

    Schmid, Andi

    2004-01-01

    Das Merkblatt enthält auf Österreich angepasste, praxisnahe Informationen zur Produktion von hochwertigen Strauchbeeren wie Himbeeren, Brombeeren, Johannisbeeren, Stachelbeeren und Heidelbeeren. Weiterhin: übersichtliche Hinweise zur Planung, Standortwahl, Sortenauswahl, Bodenvorbereitung und Pflanzung, Bewässerung, Nährstoffversorgung, Witterungsschutz, Beikrautregulierung, Ernte und Lagerung. (Diese Publikation enthält spezifische Informationen für Österreich)

  9. Nutzerorientiertes Management von materiellen und immateriellen Informationsobjekten

    OpenAIRE

    Hübsch, Chris

    2001-01-01

    Schaffung einer stabilen, erweiterbaren und skalierbaren Infrastruktur für die Bereitstellung von Diensten im Umfeld von Bibliotheken und ähnlichen wissensanbietenden Einrichtungen unter Verwendung von XML-RPC und Python.

  10. Integration of renewable and conventional power. Intraday optimization, pooling and predictive target value generation; Intraday-Optimierung, Pooling and vorausschauende Zielsollwertfuehrung. Integration von erneuerbaren und konventionellen Energien

    Energy Technology Data Exchange (ETDEWEB)

    Franke, Ruediger; Kautsch, Stephan; Blaumann, Marcel; Vogelbacher, Lothar [ABB AG, Mannheim (Germany)

    2013-10-01

    Facing increasing use of fluctuating renewable energies, the traditional unit commitment on the previous day and the use of balancing energy to account for deviations on the current day is running into limitations. Intraday optimization adapts plant schedules on the current day to new situations. This leads to frequently changing plant schedules, up to one change every 15 minutes and requires a lot of flexibility from conventional power plants. Pooling reduces the complexity of the overall system by introducing hierarchies. The predictive generation of target set points considers multiple subsequent changes of the schedule, in order to obtain a plant operation that matches at discrete accounting points and provides a smooth operation in between. The paper investigates the realization of the new techniques with online optimization. (orig.)

  11. The predictive value of markers of fibrinolysis and endothelial dysfunction in the post thrombotic syndrome. A systematic review.

    Science.gov (United States)

    Rabinovich, Anat; Cohen, Jacqueline M; Kahn, Susan R

    2014-06-01

    The post thrombotic syndrome (PTS) develops in 20-40% of deep venous thrombosis (DVT) patients. Risk factors for PTS have not been well elucidated. Identification of risk factors would facilitate individualised risk assessment for PTS. We conducted a systematic review to determine whether biomarkers of fibrinolysis or endothelial dysfunction can predict the risk for PTS among DVT patients. Studies were identified by searching the electronic databases PubMed, EMBASE, Scopus and Web of science. We included studies published between 1990 and 2013, measured biomarker levels in adult DVT patients, and reported rates of PTS development. Fourteen studies were included: 11 investigated the association between D-dimer and PTS; three examined fibrinogen; two measured von Willebrand factor; one measured plasminogen activator inhibitor-1; one assessed ADAMTS-13 (A Disintegrin and Metalloprotease with Thrombospondin type 1 repeats) and one measured factor XIII activity. Studies varied with regards to inclusion criteria, definition of PTS, time point and method of biomarker measurement. We were unable to meta-analyse results due to marked clinical heterogeneity. Descriptively, a significant association with PTS was found for D-dimer in four studies and factor XIII in one study. Further prospective research is needed to elucidate whether these markers might be useful to predict PTS development.

  12. Von der Vielfalt einer Institution

    OpenAIRE

    Kabaum, Marcel; Buck, Marc Fabian

    2013-01-01

    Von der Vielfalt von Universitäten bzw. higher education institutions (HEIs) zu sprechen heißt, sich dem Dickicht an Komplexität zu stellen, das sich zwischen ihren Ideen und Realitäten ausbreitet. Der Text führt in den Sammelband "Ideen und Realitäten von Universitäten" ein und hebt die verschiedenen disziplinären Sichtweisen sowie die internationale Breite - Deutschland, Südamerika, USA, Afghanistan und China - der Beiträge hervor. (DIPF/Orig.)

  13. Alejandro Von Humboldt

    Directory of Open Access Journals (Sweden)

    Gerardo Paz Otero

    1965-09-01

    Full Text Available Diverso fue y sigue siéndolo, el destino de los dos hermanos Humboldt, Guillermo y Alejandro. Sino que se inicia con el nacimiento: Guillermo, el mayor, nace el 22 de junio de 1767 en Potsdam, residencia de los emperadores prusianos, la ciudad de los palacios imperiales, el imperio del militarismo germano; su cuna se meció cerca al palacete de Sans-Soussi, donde Federico el Grande forja ba el poderío de Prusia, cultivaba las ciencias y las artes, anfitrionaba a los intelectuales de Europa, y era "vasallo espiritual de Volta ire", según la aguda frase de Goethe. Alejandro viene al mundo dos años después (14 de septiembre de 1769 en Berlín, en la casa burguesa de la Jagerstrasse (calle del cazador que su madre Elizabeth von Humboldt heredara de su primer esposo.

  14. Kleben von Kunststoff mit Metall

    CERN Document Server

    Brockmann, W; Käufer, H

    1989-01-01

    Das Buch behandelt das Kleben von Kunststoffen mit Metallen in einer fur den Praktiker verstandlichen und umsetzbaren Form. Es leitet zu Klebeverfahren an, die optimale Ergebnisse hinsichtlich Qualitat, Dauerhaftigkeit und Wirtschaftlichkeit liefern.

  15. Predictive value of ovarian stroma measurement for cardiovascular risk in polycyctic ovary syndrome: a case control study

    Directory of Open Access Journals (Sweden)

    Loverro Giuseppe

    2010-11-01

    Full Text Available Abstract Background To verify the feasibility of ovarian stromal evaluation and correlate ovarian parameteres (echogenicity and volume with hyperandrogenism, and both cardiovascular and metabolic risk factors in PCOS. Methods Twenty four young PCOS patients and twelve age-matched control women were enrolled. Diagnosis of PCOS was based on the Rotterdam criteria. Ultrasound ovarian study included ovarian volume, stromal volume, stromal area and stromal area/total ovarian area ratio (S/A. Concerning hormones, insulin, LH, FSH, estradiol, androstenedione, testosterone, DHEAS, 17-hydroxy-progesterone, and SHBG were measured during the early follicular phase (days 2-5. Cardiovascular risk factors were represented by fasting plasma levels of glucose, lipids (total and HDL-cholesterol, plasminogen activator inhibitor 1 (PAI-1, von-Willebrand factor (vWF, and adiponectin. Carotid intima-media thickness (C-IMT was measured as a parameter of cardiovascular risk. Results A positive correlation between the S/A ratio and plasma levels of testosterone (p Conclusions This study shows that the ultrasound measurement of ovarian stroma is a predicting factor of hyperandrogenism degree, prothrombotic factors and cardiovascular risk in patients with PCOS.

  16. Richard von Volkmann

    Science.gov (United States)

    Willy, Christian; Schneider, Peter; Engelhardt, Michael; Hargens, Alan R.

    2008-01-01

    Richard von Volkmann (1830–1889), one of the most important surgeons of the 19th century, is regarded as one of the fathers of orthopaedic surgery. He was a contemporary of Langenbeck, Esmarch, Lister, Billroth, Kocher, and Trendelenburg. He was head of the Department of Surgery at the University of Halle, Germany (1867–1889). His popularity attracted doctors and patients from all over the world. He was the lead physician for the German military during two wars. From this experience, he compared the mortality of civilian and war injuries and investigated the general poor hygienic conditions in civilian hospitals. This led him to introduce the “antiseptic technique” to Germany that was developed by Lister. His powers of observation and creativity led him to findings and achievements that to this day bear his name: Volkmann’s contracture and the Hueter-Volkmann law. Additionally, he was a gifted writer; he published not only scientific literature but also books of children’s fairy tales and poems under the pen name of Richard Leander, assuring him a permanent place in the world of literature as well as orthopaedics. PMID:18196438

  17. Aggregation und Management von Metadaten im Kontext von Europeana

    Directory of Open Access Journals (Sweden)

    Gerda Koch

    2017-09-01

    Full Text Available Mit dem In-Beziehung-Setzen und Verlinken von Daten im Internet wird der Weg zur Umsetzung des semantischen Webs geebnet. Erst die semantische Verbindung von heterogenen Datenbeständen ermöglicht übergreifende Suchvorgänge und späteres „Machine Learning“. Im Artikel werden die Aktivitäten der Europäischen Digitalen Bibliothek im Bereich des Metadatenmanagements und der semantischen Verlinkung von Daten skizziert. Dabei wird einerseits ein kurzer Überblick zu aktuellen Forschungsschwerpunkten und Umsetzungsstrategien gegeben, und darüber hinaus werden einzelne Projekte und maßgeschneiderte Serviceangebote für naturhistorische Daten, regionale Kultureinrichtungen und Audiosammlungen beschrieben.

  18. John von Neumann selected letters

    CERN Document Server

    2005-01-01

    John von Neuman was perhaps the most influential mathematician of the twentieth century, especially if his broad influence outside mathematics is included. Not only did he contribute to almost all branches of mathematics and created new fields, but he also changed post-World War II history with his work on the design of computers and with being a sought-after technical advisor to many figures in the U.S. military-political establishment in the 1940s and 1950s. The present volume is the first substantial collection of (previously mainly unpublished) letters written by von Neumann to colleagues, friends, government officials, and others. The letters give us a glimpse of the thinking of John von Neumann about mathematics, physics, computer science, science management, education, consulting, politics, and war. Readers of quite diverse backgrounds will find much of interest in this fascinating first-hand look at one of the towering figures of twentieth century science.

  19. Automatisierung von HiL Tests

    OpenAIRE

    Asbach, Lennart; Ebrecht, Lars

    2010-01-01

    Automatisierung von HiL Tests. Darstellung und Bewertung einer praktischen Umsetzung. Das Poster zeigt die Motivation, die Durchführung, einen aktuellen Stand und einen Ausblick der Testautomatisierung im Bahnlabor RailSiTe. Als Beispiel dient der Konformitätstest von ETCS-Onboard Zugrechnern, um die Einführung von ETCS zu unterstützen.

  20. Homopteren von Java, gesammelt von Herrn Edw. Jacobson

    NARCIS (Netherlands)

    Melichar, L.

    1914-01-01

    Herr Edw. Jacobson hat auf Java in den Jahren 1908— 1910 Homopteren gesammelt und mir die Bearbeitung des gesammelten Materiales übertragen. Die Jacobson’sche Ausbeute ist insoferne bemerkenswert, als dieselbe viele Mikrohomopteren enthält, welche von nichtfachkundigen Sammlern gewöhnlich nicht

  1. Properties of von Neumann entropy

    Indian Academy of Sciences (India)

    disentangled) as seen by moving observers, is used to investigate the properties of von Neumann entropy, as a measure of spin–momentum entanglement. To do so, we partition the total Hilbert space into momentum and spin subspaces so that the ...

  2. von Hippel-Lindau disease

    DEFF Research Database (Denmark)

    Binderup, Marie Louise Mølgaard; Gimsing, Steen; Kosteljanetz, Michael

    2013-01-01

    Endolymphatic sac tumours (ELSTs) of the inner ear occur in 16% of patients with the hereditary tumor syndrome von Hippel-Lindau disease (vHL). ELSTs of all sizes can cause irreversible hearing loss which can, however, be prevented through early diagnosis and treatment. We aim to emphasize the ch...

  3. [Friedrich Ludwig von Maydelli pildid Baltimaade ajaloost = Friedrich Ludwig von Maydells Baltische Geschichte in Bildern = Friedrich Ludwig von Maydell ́s Baltic history in images] / Ulrike Plath

    Index Scriptorium Estoniae

    Plath, Ulrike, 1972-

    2014-01-01

    Arvustus: Friedrich Ludwig von Maydelli pildid Baltimaade ajaloost = Friedrich Ludwig von Maydells Baltische Geschichte in Bildern = Friedrich Ludwig von Maydell ́s Baltic history in images. Eesti kunstimuuseum, Kadrioru kunstimuuseum. Tallinn 2013

  4. Influence of atrial fibrillation on plasma von Willebrand factor, soluble E-selectin, and N-terminal pro B-type natriuretic peptide levels in systolic heart failure

    DEFF Research Database (Denmark)

    Freestone, B.; Gustasson, F.; Chong, A.Y.

    2008-01-01

    Background: Endothelial dysfunction is present in patients with heart failure (HF) due to left ventricular systolic dysfunction, as well as in patients with atrial fibrillation (AF) who have normal cardiac function. it is unknown whether AF influences the degree of endothelial dysfunction in pati...

  5. N1421K mutation in the glycoprotein Ib binding domain impairs ristocetin- and botrocetin-mediated binding of von Willebrand factor to platelets

    DEFF Research Database (Denmark)

    Lanke, E.; Kristoffersson, A.C.; Isaksson, C.

    2008-01-01

    , moderately decreased plasma factor VIII (FVIII) and VWF levels, and disproportionately low-plasma VWF:RCo levels. The patients were found to be heterozygous for the novel N1421K mutation, caused by a 4263C > G transversion in exon 28 of the VWF gene coding for the A1 domain. Botrocetin- and ristocetin-mediated...... binding of plasma VWF to GPIb were reduced in the patients. In vitro mutagenesis and expression in COS-7 cells confirmed the impairment of the mutant in botrocetin- and ristocetin-mediated VWF binding to GPIb. VWF collagen binding capacity was unaffected in plasma from the heterozygous individuals as well...

  6. Activation of pathways involved in HUVEC apoptosis and proliferation. Sex hormones agonist related. Effect of hormones on von Willebrand factor and ADAMTS 13 release

    OpenAIRE

    Powazniak, Yanina

    2008-01-01

    El VWF es una glicoproteína adhesiva, sintetizada en las CE y megacariocitos. Se sintetiza en forma monomérica, luego se organiza en dímeros y se multimeriza. El VWF media la adhesión de plaquetas al subendotelio vascular dañado y lel transporte del factor FVIII. La ADAMTS13, proteasa que cliva al VWF, pertenece a la familia de metaloproteasas ADAMTS, llamadas así por la combinación característica de una desintegrina y una metaloproteasa con motivos trombospondina tipo 1. La ADAMTS13 es sinte...

  7. Distribution of von Willebrand factor levels in young women with and without bleeding symptoms: influence of ABO blood group and promoter haplotypes

    DEFF Research Database (Denmark)

    Lethagen, S.; Hillarp, A.; Ekholm, C.

    2008-01-01

    menstrual cycle, or the use of oral contraceptives. No case fulfilled the diagnostic criteria for VWD. In conclusion, low VWF:RCo was significantly more frequent in females with bleeding symptoms. However, we found no case fulfilling strict diagnostic criteria for VWD. The ABO blood group was a strong....... It was the objective of the present study to evaluate the distribution of VWF levels in young females with or without bleeding symptoms in this population, and the influence of ABO blood group and promoter haplotypes on VWF levels and to identify a possible increased prevalence of VWD in females with bleeding symptoms...

  8. Clinical experience with Optivate®, high-purity factor VIII (FVIII) product with von Willebrand factor (VWF) in young children with haemophilia A.

    Science.gov (United States)

    Matysiak, M; Bobrowska, H; Balwierz, W; Chybicka, A; Kowalczyk, J R; Shaikh-Zaidi, R; Gillanders, K; Dash, C H

    2011-09-01

    Optivate® is a high-purity FVIII/VWF product. Its safety, tolerability and efficacy in subjects ≥ 12 years have been demonstrated. This study was undertaken to assess Optivate® in children with haemophilia A. Twenty-five children, including one PUP (previously untreated patient), aged 1-6 years (mean 4.67 years) were treated with Optivate® for 26 weeks. Inhibitors were assessed every 3 months and viral status at the study start and end. Prophylaxis was used by five boys and on demand by twenty. The mean number of bleeds in the study was lower compared to the same period pre-study (12.0/child vs. 16.2/child), with fewer bleeds (P related events (5%), all were mild and non-serious. There were no clinically significant changes in vital signs, viral transmissions or inhibitors. In young children Optivate® was well tolerated, safe and efficacious. © 2011 Blackwell Publishing Ltd.

  9. High serum interleukin-8 levels in Afro-Caribbean women with pre-eclampsia. Relations with tumor necrosis factor-alpha, Duffy negative phenotype and von Willebrand factor

    NARCIS (Netherlands)

    Velzing-Aarts, FV; Muskiet, FAJ; van der Dijs, FPL; Duits, AJ

    PROBLEM: Pre-eclampsia is characterized by neutrophil activation. Interleukin-8 (IL-8) is a strong neutrophil chemo-attractant and activator. METHOD OF STUDY: We measured serum IL-8 in 13 pre-eclamptic Afro-Caribbean women and 13 gestational age-, race- and parity-matched normotensive and

  10. Shock, diaschisis and von Monakow

    Directory of Open Access Journals (Sweden)

    Eliasz Engelhardt

    2013-07-01

    Full Text Available The concept of shock apparently emerged in the middle of the 18th century (Whyett as an occurrence observed experimentally after spinal cord transection, and identified as "shock" phenomenon one century later (Hall. The concept was extended (Brown-Séquard and it was suggested that brain lesions caused functional rupture in regions distant from the injured one ("action à distance". The term "diaschisis" (von Monakow, proposed as a new modality of shock, had its concept broadened, underpinned by observations of patients, aiming at distinguishing between symptoms of focal brain lesions and transitory effects they produced, attributable to depression of distant parts of the brain connected to the injured area. Presently, diaschisis is related mainly to cerebrovascular lesions and classified according to the connection fibers involved, as proposed by von Monakow. Depression of metabolism and blood flow in regions anatomically separated, but related by connections with the lesion, allows observing diaschisis with neuroimaging.

  11. Von Hippel–Lindau disease

    Directory of Open Access Journals (Sweden)

    Juhara Haron

    2017-04-01

    Full Text Available Von Hippel–Lindau (VHL disease is a rare autosomal dominantly inherited multisystem disorder characterised by the development of a variety of benign and malignant tumours. We report a case of VHL disease that was inherited by a daughter from her father, who both presented at a young age with progressive headache and were found to have a posterior fossa haemangioblastoma (HB on magnetic resonance imaging (MRI. Multiple benign pancreatic and renal cysts were also noted in both patients.

  12. Microfinance als Geflecht von Anreizproblemen

    OpenAIRE

    Schmidt, Reinhard H.; Tschach, Ingo E.

    2001-01-01

    Während sich die Entwicklungsfinanzierung in Theorie und Praxis generell mit dem Finanzwesen in Entwicklungs- und Transformationsländern befasst, steht im Teilgebiet der Microfinance die Frage im Vordergrund, wie in diesen Ländern der Zugang ärmerer Bevölkerungsgruppen und speziell von Klein- und Kleinstunternehmer(innen), Kleinbauern und sonstigen wirtschaftlich Selbständigen aus eher niedrigen sozialen Schichten zu Kredit und anderen Finanzdiensleistungen verbessert werden kann. Obwohl es e...

  13. Moose von Inselbergen in Benin

    OpenAIRE

    Frahm, Jan-Peter; Porembski, Stefan

    1998-01-01

    Acht Leber- und zehn Laubmoosarten werden von Inselbergen aus Benin angegeben. Fünf der Lebermoose (Acrolejeunea emergens, Riccia atropurpurea, R. congoana, R. discolor, R. moenkemeyeri) und alle Laubmoose (Archidium ohioense, Brachymenium acuminatum, B. exile, Bryum arachnoideum, B. argenteum, Bryum deperssum, Garckea moenkemeyeri, Hyophila involuta, Philonotis mniobryoides und Weissia cf. edentula) werden neu für Benin angegeben. Eight liverworts and ten mosses are reported from inselber...

  14. Entwicklung und Anwendung von Methoden zur Bestimmung von Selen-Spezies in human-biologischem Material

    OpenAIRE

    Jäger, Thomas

    2014-01-01

    Selen ist essentieller Bestandteil von mehr als 25 physiologisch wichtigen menschlichen Enzymen. Der tägliche Bedarf wird überwiegend in Form von organischen Selenverbindungen wie Selenmethionin oder Selenocystein aus der Nahrung aufgenommen. Weitere Expositionswege sind die Einnahme von Nahrungsergänzungsmitteln zur Selensupplementation sowie die inhalative oder dermale Aufnahme von in erster Linie anorganischen Selenverbindungen oder elementarem Selen an Arbeitsplätzen der Selen-verarbeiten...

  15. Dr. von Braun Briefing Walt Disney

    Science.gov (United States)

    1965-01-01

    Dr. von Braun began his association with Walt Disney in the 1950s when the rocket scientist appeared in three Disney television productions related to the exploration of space. Years later, Dr. von Braun invited Disney and his associates to tour the Marshall Space Flight Center (MSFC) in Huntsville, Alabama. This photograph is dated April 13, 1965. From left are R.J. Schwinghamer from the MSFC, Disney, B.J. Bernight, and Dr. von Braun.

  16. Wohnquartiersbeschreibung: ein Instrument zur Regionalisierung von Nachbarschaften

    OpenAIRE

    Hoffmeyer-Zlotnik, Jürgen H. P.

    2001-01-01

    'Ausgehend von der Annahme, daß soziale Differenzierung sich in räumlicher Differenzierung niederschlägt, bietet eine Beschreibung der Struktur des näheren Wohnumfeldes die Möglichkeit, das Wohnquartier als Handlungsraum und Sozialisationsinstanz zur Interpretation von Umfragedaten zu nutzen. Das vorliegende Instrumentarium erlaubt es, das Wohnquartier unabhängig von Zensusdaten über Merkmale, die in der eigenen Umfrage erhoben werden, zu charakterisieren.' (Autorenreferat) 'The general hy...

  17. Research, design and education, Von Humboldt revisited

    NARCIS (Netherlands)

    Bax, M.F.T.; Doevendans, C.H.; Trum, H.M.G.J.; Langenhuizen, Anja; Ouwerkerk, Marieke van; Rosemann, Jurgen

    2001-01-01

    This paper is a result of reflection on the interrelation design-research-cultivation, and on the interpretation of Von Humboldt's maxim: 'Einheit von Forschung und Lehre', which governed the academic world in the past two centuries. It is argued that 'Forschung' should be interpreted as 'Research

  18. Diffusion von Leerstelleninseln auf Cu(111)

    NARCIS (Netherlands)

    Verheij, Laurens K.; Schlößer, Dietmar; Rosenfeld, Georg

    1998-01-01

    Die zufällige Bewegung von Leerstelleninseln wurde bisher vorwiegend in einem Bild beschrieben, das von der Diffusion einzelner Atome ausgeht. In diesem Bild kann man Inseldiffusion durch die Einstein-Beziehung für Brownsche Bewegung ((Δ r)2 = 4 D Δ t) beschreiben. Für die Diffusionskonstante D wird

  19. Von Hippel-Lindau Disease

    Directory of Open Access Journals (Sweden)

    Hes Frederik J

    2005-11-01

    Full Text Available Abstract A germline mutation in the Von-Hippel Lindau (VHL gene predisposes carriers to development of abundantly vascularised tumours in the retina, cerebellum, spine, kidney, adrenal gland and pancreas. Most VHL patients die from the consequences of cerebellar haemangioblastoma or renal cell carcinoma. The VHL gene is a tumour suppressor gene and is involved in angiogenesis by regulation of the activity of hypoxia-inducible factor 1-α (HIF1-α. Clinical diagnosis of VHL can be confirmed by molecular genetic analysis of the VHL gene, which is informative in virtually all VHL families. A patient with (suspicion for VHL is an indication for genetic counselling and periodical examination.

  20. Determining the von Mises stress power spectral density for frequency domain fatigue analysis including out-of-phase stress components

    Science.gov (United States)

    Bonte, M. H. A.; de Boer, A.; Liebregts, R.

    2007-04-01

    This paper provides a new formula to take into account phase differences in the determination of an equivalent von Mises stress power spectral density (PSD) from multiple random inputs. The obtained von Mises PSD can subsequently be used for fatigue analysis. The formula was derived for use in the commercial vehicle business and was implemented in combination with Finite Element software to predict and analyse fatigue failure in the frequency domain.

  1. Jacob Stael von Holstein ja palladionism eesti arhitektuuris / Ants Hein

    Index Scriptorium Estoniae

    Hein, Ants, 1952-

    2005-01-01

    Sõjaväeinsenerist ja arhitektist Jacob Stael von Holsteinist (1628, Pärnu-1679), tema kavandatud hoonetest ja rollist 17. sajandi II poole arhitektuuris. Fabian von Ferseni Toompeal Lossiplatsil asunud elamust (lammutati 1894) ja Maardu mõisahoonest, Hans von Ferseni Mäo mõisahoonest Järvamaal, Otto Wilhelm von Ferseni majast Toompeal, Axel von Roseni majast Tallinnas Pikk t. 28 (1670-74), Otto Reinhold von Taube majast Tartus (hävinud), J. S. von Holsteini enda hoonetest: majast Tallinnas Toompea 1, Anija mõisahoonest, elamust Riias jm. Bibliograafia lk. 452

  2. The von Meyenburg complex; Der von Meyenburg Komplex

    Energy Technology Data Exchange (ETDEWEB)

    Schwab, S.A.; Bautz, W.; Uder, M.; Kuefner, M.A. [Erlangen-Nuernberg Univ., Erlangen (Germany). Inst. fuer Radiologie

    2008-07-01

    The von Meyenburg complex (VMC) describes bile duct hamartomas and presents a rare, benign incidental finding in liver imaging. We report on a 61-year-old man, who was referred for a follow up study 14 years after remission of Hodgkin's disease. Computed tomography (CT) revealed multiple hypodense lesions throughout the liver, primary suggesting recurrent Hodgkin's disease. Previous CT-examinations, which were obtained at a later date, showed those lesions in identical distribution and morphology over the years, leading to diagnosis of multiple bile duct hamartomas (VMC). Making imaging-based diagnosis of VMC including ultrasound, CT and magnetic resonance imaging is a challenging task for the radiologist. Based on literature research findings, the impact of different modalities in the diagnostic work-up of VMC is discussed. (orig.)

  3. Neues über das Tertiär von Java und die mesozoischen Schichten von West-Borneo

    NARCIS (Netherlands)

    Martin, K.

    1888-01-01

    Die Monographie, welche unter dem Titel Die Fossilien von Java herausgegeben wird ¹), ist so weit fortgeschritten, dass sich aus den in ihr beschriebenen Gastropoden bereits eine Anzahl von Schlussfolgerungen ableiten lässt, welche für die in Bearbeitung begriffene, geologische Karte von Java von

  4. Eine Analyse des Zusammenhangs zwischen dem Konsum von Alkopops und dem Problemverhalten von Jugendlichen

    OpenAIRE

    Metzner, Cornelia Beate Isabel

    2007-01-01

    Zielsetzung: In dieser Arbeit wird untersucht, ob bei Jugendlichen ein Zusammenhang zwischen dem Konsum von Alkopops einerseits und dem sonstigen Alkoholtrinkverhalten, dem Konsum von Zigaretten und illegalen Drogen sowie weiteren Risikoverhaltensweisen andererseits besteht, ferner ob sich Unterschiede im Verhalten von Jungen und Mädchen ergeben. Theoretischer und empirischer Hintergrund: �Alkopops�, d. h. Mischgetränke diverser Hersteller aus Likör bzw. Schnaps und Limonade sowie wein- ...

  5. Analytik von Minorlipiden: Ferulasäureester von Phytosterolen (gamma-Oryzanol) in Reis

    OpenAIRE

    Miller, Andreas

    2005-01-01

    Ferulasäureestern von Phytosterolen (γ-Oryzanol) werden antioxidative und cholesterinsenkende Eigenschaften zugeschrieben. Bisher beschriebene Methoden zur Analytik von γ-Oryzanol in Reis erforderten eine aufwendige Aufreinigung des Probenextrakts. In dieser Arbeit wurde basierend auf der on-line LC-GC eine Methode entwickelt, die die simultane Bestimmung von γ-Oryzanol-Gehalt und Sterylferulat-Verteilung ohne Aufreinigung des Probenextrakts erlaubt. Mit Hilfe der Technik wurden die natürlich...

  6. Redoxspeziation von endlagerrelevanten Elementen mit Hilfe von Trennmethoden gekoppelt an ein Massenspektrometer mit induktiv gekoppeltem Plasma

    OpenAIRE

    Graser, Carl-Heinrich

    2015-01-01

    Im Rahmen dieser Arbeit wurden Redoxspeziationsanalysen von Eisen, Neptunium und Plutonium per CE-SF-ICP-MS durchgeführt. Durch Optimierung der Trennparameter konnten Trennungen der Pu Oxidationsstufen III bis VI und Trennungen der Np Oxidationsstufen IV bis VI binnen 15 Minuten mit einer Nachweisgrenze von 10-12 M durchgeführt werden. Die Trennung der Fe Oxidationsstufen II und III gelang in weniger als 5 Minuten mit einer Nachweisgrenze von 5-10-8 M.

  7. THE DIGITAL VON FAHRENHEID PYRAMID

    Directory of Open Access Journals (Sweden)

    M. Bura

    2017-08-01

    Full Text Available 3D Scanners Lab from Digital Humanities Laboratory at the University of Warsaw initiated the scientific project, the purpose of which was to call attention to systematically penetrated and devastated pyramid-shaped tomb from the XVIII/XIX century, of family von Fahrenheid in Rapa in Banie Mazurskie commune (NE Poland. By conducting a series of non-invasive studies, such as 3D inventory using terrestrial laser scanning (TLS, thermal imaging, georadar measurements (around and inside the tomb and anthropological research of mummified remains as well - the complete dataset was collected. Through the integration of terrestrial (TLS and airborne laser scanning (ALS authors managed to analyse the surroundings of Fahrenheid pyriamid and influence of some objects (like trees on the condition and visibility of the Pyramids in the landscape.

  8. Die Wirkung von Desacetylcefotaxin, einem Metaboliten von Cefotaxim, in vitro und auf die experimentelle Infektion mit Escherichia coli

    OpenAIRE

    Wirbelauer, J.; Hof, H.; Hacker, Jörg

    2009-01-01

    Die MHK-Werte von Desacetylcefotaxim gegen verschiedene, z. T. ampicillinresistente Stämme von Escherichia coH, die mit Hilfe einer Agardilutionsmethode erhoben wurden, waren höher als die von Cefotaxim und Ceftriaxon, jedoch niedriger als die von Cefoxitin. In einem Modell der systemischen Infektion der Maus mit einem plasmidtragenden, betalactamaseproduzierenden Stamm von E. coli führte die Therapie mit Desacetylcefotaxim zu einer starken Reduktion der Keime pro Leber. Im Vergleich zur Ther...

  9. VON WISPR Family Processors: Volume 1

    National Research Council Canada - National Science Library

    Wagstaff, Ronald

    1997-01-01

    ...) and the background noise they are embedded in. Processors utilizing those fluctuations such as the von WISPR Family Processors discussed herein, are methods or algorithms that preferentially attenuate the fluctuating signals and noise...

  10. Von Onlineplattformen und mittelalterlichen Märkten

    Directory of Open Access Journals (Sweden)

    Claudius Gräbner

    2017-12-01

    Full Text Available Mit der zunehmenden Digitalisierung und Vernetzung ökonomischer Systeme haben plattformbasierte Interaktionsbeziehungen stark an Bedeutung gewonnen. Hier werden zwei oder mehr Nutzungsgruppen durch eine dritte Seite, die Plattform, zusammengebracht. Die Interaktion wird in solchen zweiseitigen Märkten von den Plattformbetreibern kontrolliert. Kreditkartensysteme, Softwaremärkte oder werbefinanzierte Online-Communities stellen typische Beispiele dar. Da die Analyse von zweiseitigen Märkten mit Gleichgewichtsmodellen aufgrund der algebraischen Struktur des Problems in der Regel nicht praktikabel ist, präsentieren wir im vorliegenden Beitrag ein agentenbasiertes Modell, welches in einem kürzlich erschienenen Artikel ausführlicher diskutiert wird. Anhand von illustrativen Beispielen verdeutlichen wir die Implikationen eines agentenbasierten Ansatzes für die Innovationsökonomik im Allgemeinen und das Studium von Technologieentwicklung im Besonderen.

  11. Johann Friedrich Wilhelm Adolf von Baeyer

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 19; Issue 6. Johann Friedrich Wilhelm Adolf von Baeyer: A Pioneer of Synthetic Organic Chemistry. Gopalpur Nagendrappa. General Article Volume 19 Issue 6 June 2014 pp 489-522 ...

  12. Titanisierung von Implantatoberflächen

    Science.gov (United States)

    Zimmermann, Hanngörg; Heinlein, Markus; Guldner, Norbert W.

    Titan gilt seit Jahrzehnten als einer der wichtigsten Implantatwerkstoffe in der Medizin. Neben den guten mechanischen Eigenschaften (Leichtigkeit, hohe Festigkeit etc.), besitzen Titanimplantate vor allem eine hervorragende Körperverträglichkeit, so dass die Implantate optimal in den humanen Organismus integriert werden [1]. Ist jedoch aufgrund der Anforderungen an das Implantat eine hohe Flexibilität und/ oder Elastizität gefragt, so scheidet der Werkstoff Titan aufgrund seiner spröden und unflexiblen Materialeigenschaften aus. Die Folge ist der Einsatz von Implantatmaterialien, sowohl künstlichen als auch biologischen Ursprungs, welche nicht selten eine unzureichende Biokompatibilität aufweisen und somit zu Fremdköper- und immunologischen Reaktionen und Einkapselung des Implantates führen können. Die Erhöhung der Körperverträglichkeit, eine Adaption an das biologische Umfeld und eine hohe Biokompatibilität sind demzufolge die wichtigsten Eigenschaften bei der bedarfsgerechten Herstellung von Implantaten und Implantatoberflächen. Zur Gestaltung von innovativen, biokompatiblen Oberflächen stehen unterschiedliche technische Lösungsansätze zur Verfügung. Zum einen besteht die Möglichkeit, geeignete Oberflächeneigenschaften aus dem Grundmaterial selbst zu optimieren. Dies geschieht unter anderem durch Modifikation der Werkstoffoberflächen in Form von Texturierungen und Oberflächenrauhigkeiten. Zum anderen können die Oberflächeneigenschaften unabhängig von denen des Trägermaterials gestaltet werden. Durch Funktionalisierung der Oberflächen mit geeigneten Beschichtungen oder der Zugabe von Medikamenten (Drug Eluting) werden die Kunststoffimplantate dahingehend verändert, dass eine Steigerung der Körperakzeptanz erreicht wird. Die Titanbeschichtung von Implantatoberflächen kombiniert die positiven Materialeigenschaften von Titan und Polymer.

  13. 50th birthday of Christian von Ferber

    Directory of Open Access Journals (Sweden)

    2011-06-01

    Full Text Available On May 15, 2011 Christian von Ferber - member of the Editorial Board of "Condensed Matter Physics" and renowned expert in the fields of soft matter physics and complex systems - celebrated his 50th birthday. The Editorial board of CMP, colleagues and friends warmy congratulate Christian von Ferber and wish him and his family continuing good health and to enjoy many adventures and discoveries in his future scientific travels!

  14. The classification problem for von Neumann factors

    DEFF Research Database (Denmark)

    Sasyk, R.; Törnquist, Asger Dag

    2009-01-01

    We prove that it is not possible to classify separable von Neumann factors of types II, II or III, 0 ≤ λ ≤ 1, up to isomorphism by a Borel measurable assignment of "countable structures" as invariants. In particular the isomorphism relation of type II factors is not smooth. We also prove...... that the isomorphism relation for von Neumann II factors is analytic, but is not Borel....

  15. Hullud päevad von Krahlis

    Index Scriptorium Estoniae

    2006-01-01

    Von Krahli Teatris mängitakse neil päevi neli korda Peeter Jalaka lavastuses Tõnu Kõrvitsa kammeroopereid "Tuliaed" ja "Mu luiged, mu mõtted", mille aluseks on luuletaja Marie Heibergi saatus. Libreto autor on Maarja Kangro. Kammerooperid tulevad lavale Von Krahli Teatri ja Nargen Opera koostöös. Esitavad Kädy Plaas, Helen Lokuta, Nargen Opera koor ja Tallinna Kammerorkester, dirigent Tõnu Kaljuste

  16. Bedeutung von Umwelt- und Organismusfaktoren bei Autoaggressionen

    OpenAIRE

    Rohmann, Ulrich H.; Elbing, Ulrich; Hartmann, Hellmut

    1988-01-01

    In der vorliegenden Arbeit werden übergeordnete Hypothesen zu autoaggressiven Verhaltensweisen formuliert, wobei prozeßhafte Abläufe von umweltbezogenen und organischen Variablen angenommen werden. Eine solche dynamische Beziehung hat ihre Bedeutung sowohl für verursachende als auch aufrechterhaltende Faktoren. In einer Querschnittuntersuchung lassen sich Korrelationen von Tageszeit- und Tätigkeitscharakteristiken (umweltbezogene Variablen) zur Autoaggressionshäufigkeit und Pulsfrequenz (Orga...

  17. Visualisierung von typisierten Links in Linked Data

    Directory of Open Access Journals (Sweden)

    Georg Neubauer

    2017-09-01

    Full Text Available Das Themengebiet der Arbeit behandelt Visualisierungen von typisierten Links in Linked Data. Die wissenschaftlichen Gebiete, die im Allgemeinen den Inhalt des Beitrags abgrenzen, sind das Semantic Web, das Web of Data und Informationsvisualisierung. Das Semantic Web, das von Tim Berners Lee 2001 erfunden wurde, stellt eine Erweiterung zum World Wide Web (Web 2.0 dar. Aktuelle Forschungen beziehen sich auf die Verknüpfbarkeit von Informationen im World Wide Web. Um es zu ermöglichen, solche Verbindungen wahrnehmen und verarbeiten zu können sind Visualisierungen die wichtigsten Anforderungen als Hauptteil der Datenverarbeitung. Im Zusammenhang mit dem Sematic Web werden Repräsentationen von zuhammenhängenden Informationen anhand von Graphen gehandhabt. Der Grund des Entstehens dieser Arbeit ist in erster Linie die Beschreibung der Gestaltung von Linked Data-Visualisierungskonzepten, deren Prinzipien im Rahmen einer theoretischen Annäherung eingeführt werden. Anhand des Kontexts führt eine schrittweise Erweiterung der Informationen mit dem Ziel, praktische Richtlinien anzubieten, zur Vernetzung dieser ausgearbeiteten Gestaltungsrichtlinien. Indem die Entwürfe zweier alternativer Visualisierungen einer standardisierten Webapplikation beschrieben werden, die Linked Data als Netzwerk visualisiert, konnte ein Test durchgeführt werden, der deren Kompatibilität zum Inhalt hatte. Der praktische Teil behandelt daher die Designphase, die Resultate, und zukünftige Anforderungen des Projektes, die durch die Testung ausgearbeitet wurden.

  18. ˝FLUMINENSIA˝ VON FRAN KURELAC

    Directory of Open Access Journals (Sweden)

    Leopoldina Veronika Banaš

    1990-01-01

    Full Text Available Das Buch "Fluminensia" (1862 von Fran Kurelac enthält die für die Schulfestlichkeiten geschriebenen Reden, Gelegenheitsgedichte - Ehrengedichte den bedeutenden und verdienstvollen Zeitgenossen gewidmet: dem Bischof von Senj und Modrus" Mirko Ožegović, Bartol Zmajic von Bakar, dem kroatischen Ban Josip Jelačić u.a. Danach folgen Aufrufe ("Proglasi" aus stürmischem 1848, gerichtet auf die Granzlandbewohner, Deutscher, ungarische Kroaten, Rumänen und Slawonier. Die Aufrufe wurden von Kurelac im Namen der Banalregierung beschrieben. Am Ende des Buches steht eine sprachwissenschaftliche Abhandlung über die ubstantivbiegung. Die für die Schulfestlichkeiten geschreibenen Reden sind wissenschaftliche Inhalte, essaystisch-didaktisch gestalltet, mit der Meldung über die Bedeutung der Wisenschaft, über die Bedeutung und Rolle der Sprache und des Buches für den Fortschritt des Volkes. Der Verfasser widmete dieses Buch seinen ehemaligen Schülern. "Fluminensia" nimmt eine wichtige Stelle in literarischer und sprachwissenschaftlicher Schöpfung auf dem Gebiet von Rijeka und Kroatien im 19. Jahrhundert ein.

  19. Privatiserung von Geschichte. Probleme einer differenzierten Aufarbeitung

    Directory of Open Access Journals (Sweden)

    Birthe Kundrus

    2000-11-01

    Full Text Available Ausgangspunkt der Untersuchung von Vera Neumann ist die These, daß im Krieg Erlebtes und Erlittenes in den Wiederaufbau- und Wirtschaftswunderjahren Westdeutschlands einem Thematisierungstabu unterlegen sei. Anhand von 50 Interviews, die in den 80er Jahren im Rahmen des von Lutz Niethammer geleiteten Projekts „Lebensgeschichte und Sozialgeschichte im Ruhrgebiet 1930–1960“ (LUSIR entstanden sind und die sie jetzt anhand der Tonbandprotokolle und Abschriften ein zweites Mal auswertet, möchte die Historikerin diese Verschüttungen aufspüren. Im Anschluß an Niethammers These der „Privatisierung von Geschichte“ will sie zeigen, daß seelische und körperliche Kriegsfolgen wie Deprivations- und Überlastungsgefühle, der Verlust von Angehörigen und Kriegsbeschädigungen „privatisiert“, d.h. an die Familien übertragen wurden. Dort seien dann in erster Linie die weiblichen Familienmitglieder mit der Versorgungs- und Pflegearbeit konfrontiert worden. An vier Fallbeispiele schließt sich eine detaillierte Auswertung des gesamten Interviewmaterials an. Diesen Teilen folgt ein Abschnitt zur staatlichen Kriegsopferversorgung in der frühen Bundesrepublik.

  20. A new von Mises probabilistic formula for quartet invariants

    International Nuclear Information System (INIS)

    Giacovazzo, C.; Camalli, M.; Spagna, R.

    1989-01-01

    Von Mises formulas for quartet invariants, even is useful in most cases of practical interest, suffer from some systematic errors. A new von Mises formula is suggested with better theoretical features. (orig.)

  1. Kerttu Wagner. Die historischen romane von Jaan Kross / Wolfgang Drechsler

    Index Scriptorium Estoniae

    Drechsler, Wolfgang, 1963-

    2001-01-01

    Arvustus: Wagner, Kerttu. Die historischen Romane von Jaan Kross : am Beispiel einer Untersuchung der deutschen und englischen Übersetzungen von "Professor Martensi ärasõit" (1984). Frankfurt am Main [etc.] : P. Lang, 2001.

  2. IAS 25, Bilanzierung von Finanzinvestitionen (Accounting for Investments)

    OpenAIRE

    Steiner, Manfred

    1997-01-01

    IAS 25, Bilanzierung von Finanzinvestitionen (Accounting for Investments). - In: Rechnungslegung nach International Accounting Standards (IAS) / hrsg. von Jörg Baetge ... - Stuttgart : Schäffer-Poeschel, 1997. - S. 923-953

  3. Borel reductibility and classification of von neumann algebras

    DEFF Research Database (Denmark)

    Sasyk, R.; Törnquist, Asger Dag

    2009-01-01

    We announce some new results regarding the classification problem for separable von Neumann algebras. Our results are obtained by applying the notion of Borel reducibility and Hjorth's theory of turbulence to the isomorphism relation for separable von Neumann algebras....

  4. Medien und Berufsvorstellungen von Kindern: eine experimentelle Studie zum Einfluss von Kinderbüchern auf das Berufsspektrum von Kindergartenkindern

    OpenAIRE

    Brüggemann, Tim; Gehrau, Volker; Handrup, Jutta

    2015-01-01

    "Der Beitrag thematisiert zunächst den Stand der beruflichen Orientierung von Jugendlichen sowie die pädagogischen Bemühungen beim Übergang Schule-Beruf, insbesondere im Hinblick auf eine Erweiterung des häufig engen Spektrums von Berufen, die bei der Berufswahl berücksichtig werden. Dabei richten sich die Bestrebungen, diesem Problem entgegenzuwirken, bislang vor allem auf Jugendliche. Anschließend wird anhand vorliegender Ergebnisse aus der Medienforschung diskutiert, in welcher Weise Masse...

  5. Gemeinsam hilfreich oder einsam lästig? Beurteilung von praktikumsbegleitenden Weblogs von angehenden Lehrpersonen

    Directory of Open Access Journals (Sweden)

    Nives Egger

    2017-02-01

    Full Text Available Weblogs werden an Hochschulen vermehrt zur Unterstützung von Lern- und Reflexionsprozessen eingesetzt, in der Lehrer/innenbildung auch zunehmend während der berufspraktischen Ausbildung. Die Studierenden beurteilen den Einsatz von Weblogs jedoch unterschiedlich. Dabei ist wenig bekannt, welchen Einfluss die Vergabe und das Erhalten von Peerfeedback auf den Beurteilungsprozess von praktikumsbegleitenden Weblogs sowie auf den Umfang von Blogpostings haben. Im folgenden Beitrag wird dieser Frage mittels einer Befragung von 74 angehenden Lehrpersonen nachgegangen, die praktikumsbegleitende Weblogs mit oder ohne Peerfeedback nutzten, um über herausfordernde Ereignisse im Praktikum zu reflektieren. Die Ergebnisse zeigen, dass Studierende, die Peerfeedback erhielten und andere Blogbeiträge kommentierten, den Weblogeinsatz nützlicher einschätzen sowie eine höhere Motivation und positivere Einstellung gegenüber den Einsatz von Weblogs aufweisen als Studierende, die ohne Peerfeedback bloggen. Keinen Einfluss hat Peerfeedback auf den Umfang der Blogbeiträge und auf die dafür aufgewendete Zeit.

  6. [Anja Wilhelmi. Lebensweltlen von Frauen der deutschen Oberschicht im Baltikum (1800-1939). Eine Untersuchung anhand von Autobiographien] / Alexander Ewig

    Index Scriptorium Estoniae

    Ewig, Alexander, 1980-

    2011-01-01

    Arvustus: Wilhelmi, Anja. Lebenswelten von Frauen der deutschen Oberschicht im Baltikum (1800-1939). Eine Untersuchung anhand von Autobiographien. (Veröffentlichungen des Nordost-Instituts, 10.) (Wiesbaden : HArrassowitz 2008)

  7. Gasification of liquid manure; Vergasung von Guelle

    Energy Technology Data Exchange (ETDEWEB)

    Gudenau, H.W.; Hoberg, H.; Hirsch, U. [Technische Hochschule Aachen (Germany). Inst. fuer Eisenhuettenkunde

    1996-12-31

    The potential of thermal use of liquid manure is investigated. It is recommended to separate the liquid and solid fraction. While the liquid fraction can be used as fertilizer, the solid fraction can be used for generating a fuel gas for combined heat and power generation. (orig) [Deutsch] Die Untersuchungen haben ergeben, dass in der thermischen Verwertung von Guelle ein bisher nur wenig genutztes Potential vorliegt. Die zum Anbau von Getreide notwendige Duengung kann durch Separation von Guelle in Fest- und Duennfraktion effektiver und kostenguenstiger durchgefuehrt werden. Der Naehrstoffgehalt des Guellefeststoffs sollte durch thermische Aufbereitung aufkonzentriert werden, so dass eine Vermarktung auch mit laengeren Transpoertwegen darstellbar ist. Die bei der thermischen Behandlung gewonnene Waerme kann prozessintern genutzt und ueberschuessige Waerme an Abnehmer in der naeheren Umgebung geliefert werden. Genauso besteht die Moeglichkeit, ein Brenngas zu erzeugen und die Energie mit Kraft-Waerme-Kopplung zu nutzen. (orig)

  8. Gasification of liquid manure; Vergasung von Guelle

    Energy Technology Data Exchange (ETDEWEB)

    Gudenau, H W; Hoberg, H; Hirsch, U [Technische Hochschule Aachen (Germany). Inst. fuer Eisenhuettenkunde

    1997-12-31

    The potential of thermal use of liquid manure is investigated. It is recommended to separate the liquid and solid fraction. While the liquid fraction can be used as fertilizer, the solid fraction can be used for generating a fuel gas for combined heat and power generation. (orig) [Deutsch] Die Untersuchungen haben ergeben, dass in der thermischen Verwertung von Guelle ein bisher nur wenig genutztes Potential vorliegt. Die zum Anbau von Getreide notwendige Duengung kann durch Separation von Guelle in Fest- und Duennfraktion effektiver und kostenguenstiger durchgefuehrt werden. Der Naehrstoffgehalt des Guellefeststoffs sollte durch thermische Aufbereitung aufkonzentriert werden, so dass eine Vermarktung auch mit laengeren Transpoertwegen darstellbar ist. Die bei der thermischen Behandlung gewonnene Waerme kann prozessintern genutzt und ueberschuessige Waerme an Abnehmer in der naeheren Umgebung geliefert werden. Genauso besteht die Moeglichkeit, ein Brenngas zu erzeugen und die Energie mit Kraft-Waerme-Kopplung zu nutzen. (orig)

  9. Spectral theory and quotients in Von Neumann algebras | West ...

    African Journals Online (AJOL)

    In this note we consider to what extent the functional calculus and the spectral theory in von Neumann algebras are preserved by the taking of quotients relative to two-sided ideals of the von Neumann algebra. Keywords:von Neumann algebra, functional calculus, spectral theory, quotient algebras. Quaestiones ...

  10. Der Einfluss von sozialer Ungleichheit und kulturellen Unterschieden auf die Wahrnehmung von finanziellen und Arbeitsplatzrisiken: Überlegungen zur Risikogesellschaft

    OpenAIRE

    Abbott, David; Quilgars, Deborah; Jones, Anwen

    2006-01-01

    Der vorliegende Artikel beruht auf Daten einer Studie, die sich mit der Frage beschäftigt, wie verschiedene soziale und kulturelle Gruppen die Risiken von Einkommens- und Arbeitsplatzverlust wahrnehmen und darauf reagieren. Autoren wie LASH, DOUGLAS und LUPTON betonten die Bedeutung von Gruppenzugehörigkeit und sozialen Kategorien für die Strukturierung der Reaktionsweisen auf verschiedene Risikoarten. Sie sprechen daher lieber von Risikokulturen als von der Risikogesellschaft. Trotzdem erken...

  11. Bewertung von Fahrzeuggeräuschen

    Science.gov (United States)

    Genuit, Klaus; Schulte-Fortkamp, Brigitte; Fiebig, André; Haverkamp, Michael

    Bei der Wahrnehmung und Beurteilung eines Automobils sind unzählige Merkmale und Eigenschaften von Bedeutung. Dabei können Merkmale objektiv-technisch beschrieben werden, wie Angaben zur Motorisierung, Höchstgeschwindigkeit, Drehmoment, zulässige Zuladung, Verbrauch usw. Daneben sind weitere Eigenschaften von Bedeutung, die sich einer einfachen objektiv-technischen Beschreibung entziehen. Hier sind Begriffe zu nennen, wie Sicherheit, allgemeine Qualitätsanmutung, Design, Ergonomie, Komfort, Haptik, Fahrdynamik, Zuverlässigkeit, die deutlich schwieriger objektiv erfassbar und beschreibbar sind (Abb. 4.1).

  12. Asymptotic analysis of a von Koch beam

    International Nuclear Information System (INIS)

    Carpinteri, Alberto; Pugno, Nicola; Sapora, Alberto

    2009-01-01

    Fractal geometry is used in diverse research areas, being an useful tool in describing the mechanical behaviour of natural and man-made structures. In this paper, the structural behaviour of a von Koch cantilever beam is analyzed in the small deformations regime. Analytical recursive formulae for the strain energy scaling are derived, which have been found in good agreement with numerical simulations. Energy considerations suggest a peculiar scaling for the beam rigidity in order to prevent compliance divergence. The results are then extended to evaluate the stiffness matrix of a von Koch beam.

  13. Von Mumien, Cyborgs und Röntgenbildern

    Directory of Open Access Journals (Sweden)

    Regina Schleicher

    2004-03-01

    Full Text Available Unter dem Titel Techniken der Reproduktion liegt ein Sammelband vor, der die Beiträge einer Tagung an der Universität Paderborn vom Dezember 2001 enthält. In enger Verknüpfung verschiedener disziplinärer Perspektiven werden Schlaglichter auf eine Vielzahl von Themen geworfen, die sich mit dem Begriff „Reproduktion“ verbinden. Dabei wird deutlich, wie eng die Geschichte der Medien und die Entwicklung von Technologien der biologischen Fortpflanzung miteinander verzahnt sind.

  14. Die Verteilung und Eigenschaften von Bodenformen in der Deutschen Bucht, eine Rekonstruktion der Karten von Ulrich (1973)

    DEFF Research Database (Denmark)

    Winter, Christian; Lefebvre, Alice; Benninghoff, Markus

    2015-01-01

    Entstehung, Gestalt und Dynamik von Bodenformen in vergleichsweise kleinen Untersuchungsgebieten ist die Arbeit von ULRICH (1973) über die Verteilung von Bodenformen in der Deutschen Bucht bis heute die einzige verfügbare zusammenhängende Darstellung für die deutsche Nordseeküste. Die analogen Karten und die...

  15. Evaluation von Bildungssoftware im Spannungsfeld von Objektivität und praktischer Anwendung

    Directory of Open Access Journals (Sweden)

    Cornelia Biffi

    2002-05-01

    Full Text Available Das Angebot an Bildungs- bzw. Lernsoftware umfasst eine breite Palette von sehr unterschiedlichen Produkten. Eigentliche Unterrichtssoftware, die speziell für den Unterricht hergestellt und auf Lehrmittel und Curriculum abgestimmt ist, gibt es kaum. Im Projekt «Lernsoftware Evaluation» des Pestalozzianums Zürich ermitteln Lehrpersonen die Qualität von Bildungssoftware, indem sie diese im Unterricht einsetzen und anhand eines Kriterienrasters beurteilen. Eine Analyse der in der Evaluation generierten Daten belegt die Problematik des Anspruchs einer objektiven Qualitätsbeurteilung. Es werden die Probleme bei der Anwendung von Kriterienraster und Beurteilungsmodus aufgezeigt und ermittelt, worin die subjektiven Qualitätsmassstäbe der Evaluierenden begründet sind. Diese Ausführungen sind Teil eines Forschungsprojekts für die Weiterentwicklung einer theoretisch fundierten, aber dennoch praxisnahen Evaluation von Bildungssoftware.

  16. Von der Medienwirkungsbehauptung zur erziehungswissenschaftlichen Medienrezeptionsforschung. Vorschlag zur Analyse von Filmkommunikaten

    Directory of Open Access Journals (Sweden)

    Barbara Drinck

    2001-04-01

    Full Text Available Im Hinblick auf die Erforschung spezifischer Zusammenhänge von Medienkonsum und der Herausbildung von Einstellungen und Handlungen wird eine konstruktivistische Theorieorientierung plausibilisiert, indem zunächst auf den Stand der Medienwirkungsforschung eingegangen und vor dem Hintergrund einer begründeten Kritik des Wirkungsverständnisses auf die Notwendigkeit einer medienrezeptionswissenschaftlichen Forschungsalternative hingewiesen wird. Weiterhin wird der Stand der (erziehungswissenschaftlichen Medienrezeptionsforschung erörtert. Sodann werden Elemente einer konstruktivistischen Methodologie von Medienrezeptionsforschung beschrieben, die am Beispiel der Rezeption von Filmen konkretisiert werden. Dabei wird das Konzept des Kommunikates (S.J. Schmidt als Ausgangspunkt genommen, ein Vorschlag für eine Beschreibungssprache für (Film- Kommunikate entwickelt und eine Adaption des Ansatzes filmischer Narration zur Sprache gebracht.

  17. Erzeugung gleichverteilter Stichproben von Lozenge-Teilungen mittels Kopplung von Markovketten

    OpenAIRE

    Keller, Peter

    2011-01-01

    Aus dem Inhalt: 1 Einleitung 2 Eigenschaften der Lozengeteilungen 3 Coupling From The Past (CFTP) 4 Simulation von uniform verteilten Lozengeteilungen 5 Programmlisting und Diskussion der Implementierung 6 Ausblick A Anhang

  18. Der Briefwechsel zwischen Alexander von Humboldt und Karl Ernst von Baer

    Directory of Open Access Journals (Sweden)

    Thomas Schmuck

    2012-10-01

    Full Text Available Zusammenfassung Der kurze, nicht vollständig erhaltene Briefwechsel zwischen Alexander von Humboldt und Karl Ernst von Baer behandelt sehr verschiedene Themen: Politik, Kriegsgefahr, den Wissenschaftsbetrieb, Auszeichnungen und Tagungen, Embryologie und Cholera. Gemeinsam mit Briefen und Reden ergibt sich dabei ein differenziertes Bild der Beurteilung der beiden Wissenschaftler durch den jeweils anderen. Während Baer sich als Bewunderer Humboldts erweist, erscheint umgekehrt Humboldts Einschätzung Baers als ambivalent. Abstract The short, not completely preserved correspondence between Alexander von Humboldt and Karl Ernst von Baer deals with a wide range of subjects: politics and the danger of war, academic activities, scientific awards and conferences, aspects of embryology and the cholera. Letters to third persons and speeches, together with the correspondence between Humboldt and Baer show a differentiated pattern of mutual appraisal: While Baer always remained an admirer of the elder naturalist, Humboldt’s estimation was characterized by ambivalence.

  19. Untersuchungen zur Entwicklung von Satellitengalaxien

    Science.gov (United States)

    Seidel, Björn

    2002-01-01

    Gleichgewichtsmodelle ein- und zweikomponentiger Satellitengalaxien werden erzeugt und die Gezeiteneinwirkungen der als starres äußeres Potential angenommenen Milchstraße auf sie betrachtet. Eine erste Reihe von Simulationen mit anfänglich kugelsymmetrischen einkomponentigen Satelliten zeigt, daß sich nach elliptischer Deformation ein Balken und Schweife ungleicher Länge ausbilden, deren Aussehen sich periodisch ändert. Mithilfe von Vergleichssimulationen wurden folgende Phänomene am Satelliten entdeckt: (1) Hochdichtebereiche in den Schweifen, (2) Niedrigdichtebereiche um den Kern bzw. Balken und (3) ein oft verdeckter Balken. Analysiert wird das Erscheinungsbild in Zeitabhängigkeit. Die Teilchen gehen dem Kern über den Balken verloren und bewegen sich entlang gewisser stets gleich aussehender charakteristischer Strukturen in die Schweife. Nach einer Herleitung allgemeiner Größen des mehrkomponentigen Kingprofils werden drei stabile Standardmodelle zweikomponentiger Satellitengalaxien mit Massenverhältnis 1:10 (baryonische zu dunkle Materie) und unterschiedlicher Verteilung der dunklen und sichtbaren Materie gefunden. Ohne die Allgemeinheit der Ergebnisse zu beeinträchtigen, wurde dabei die Große Magellanische Wolke als Grundlage der Modelle genommen. Nach geeigneter Wahl der Bahn, zu der der Gezeitenradius des verwendeten dreikomponentigen Milchstraßenpotentials sowohl analytisch als auch numerisch berechnet wird, werden Simulationen der Modelle analysiert. Hauptaugenmerk ist das unterschiedliche Verhalten der Komponenten. Hauptergebnisse: (1) Es ist möglich, große Anteile dunkler, jedoch nur geringe sichtbarer Materie abzulösen. Dunkle und sichtbare Materie können unterschiedliche morphologische Strukturen bilden. (2) Je nach Konzentration der Komponenten ist die Eigengravitation der Teilchen mehr oder weniger für das Aussehen bestimmend. (3) Die Kernauflösung des Satelliten findet im Perigalaktikum (PG), sein Zerfall aber erst im

  20. A note on derivations of Murray–von Neumann algebras

    Science.gov (United States)

    Kadison, Richard V.; Liu, Zhe

    2014-01-01

    A Murray–von Neumann algebra is the algebra of operators affiliated with a finite von Neumann algebra. In this article, we first present a brief introduction to the theory of derivations of operator algebras from both the physical and mathematical points of view. We then describe our recent work on derivations of Murray–von Neumann algebras. We show that the “extended derivations” of a Murray–von Neumann algebra, those that map the associated finite von Neumann algebra into itself, are inner. In particular, we prove that the only derivation that maps a Murray–von Neumann algebra associated with a factor of type II1 into that factor is 0. Those results are extensions of Singer’s seminal result answering a question of Kaplansky, as applied to von Neumann algebras: The algebra may be noncommutative and may even contain unbounded elements. PMID:24469831

  1. A note on derivations of Murray-von Neumann algebras.

    Science.gov (United States)

    Kadison, Richard V; Liu, Zhe

    2014-02-11

    A Murray-von Neumann algebra is the algebra of operators affiliated with a finite von Neumann algebra. In this article, we first present a brief introduction to the theory of derivations of operator algebras from both the physical and mathematical points of view. We then describe our recent work on derivations of Murray-von Neumann algebras. We show that the "extended derivations" of a Murray-von Neumann algebra, those that map the associated finite von Neumann algebra into itself, are inner. In particular, we prove that the only derivation that maps a Murray-von Neumann algebra associated with a factor of type II1 into that factor is 0. Those results are extensions of Singer's seminal result answering a question of Kaplansky, as applied to von Neumann algebras: The algebra may be noncommutative and may even contain unbounded elements.

  2. Soolopartiid Von Krahli katuse all / Kristi Eberhart

    Index Scriptorium Estoniae

    Eberhart, Kristi

    2007-01-01

    Von Krahli Teatri kolmest lavastusest: "Erki ja Tiina" (lavastaja Mart Kangro, tantsivad Erki Laur ja Tiina Tauraite), "Faust" (J. W. Goethe ainetel tekst ja lavastus Taavi Eelmaa, muusika ja laulud Chalice, osades Jarek Kasar ja Rein Pakk), "Hamletid" (William Shakespeare'i ainetel kontseptsiooni, lavastuse, koreograafia, kujunduse, valguse autor Sasha Pepeljajev, video- ja helikunstnik Taavet Jansen. Esitaja Juhan Ulfsak)

  3. Alexander von Humboldt and Coenraad Jacob Temminck

    NARCIS (Netherlands)

    Raat, A.J.P.

    1976-01-01

    INTRODUCTION In the archives of the Rijksmuseum van Natuurlijke Historie in Leiden there is a map with three letters written by Alexander von Humboldt (17691859) to the first director of the Museum, Coenraad Jacob Temminck (1778-1858). The map, the hard cover of John Gould's "Synopsis of the birds

  4. Differential functional von Foerster equations with renewal

    Directory of Open Access Journals (Sweden)

    H.Leszczyński

    2008-06-01

    Full Text Available Natural iterative methods converge to the exact solution of a differential-functional von Foerster-type equation which describes a single population dependent on its past time and state densities as well as on its total size. On the lateral boundary we impose a renewal condition.

  5. Wege zur Entdeckung von Communities in Folksonomies

    OpenAIRE

    Jäschke, Robert; Hotho, Andreas; Schmitz, Christoph; Stumme, Gerd

    2006-01-01

    Ein wichtiger Baustein des neu entdeckten World Wide Web - des "Web 2.0" - stellen Folksonomies dar. In diesen Systemen können Benutzer gemeinsam Ressourcen verwalten und mit Schlagwörtern versehen. Die dadurch entstehenden begrifflichen Strukturen stellen ein interessantes Forschungsfeld dar. Dieser Artikel untersucht Ansätze und Wege zur Entdeckung und Strukturierung von Nutzergruppen ("Communities") in Folksonomies.

  6. Hans von Engel and the ICPIG Conference

    International Nuclear Information System (INIS)

    Franklin, R.

    2000-01-01

    The history of the, organized by Hans von Engel, International Conference on Phenomena in Ionized Gases is presented: Oxford (1953), Delft (1955), Venice (1957), Uppsala (1959), Munich (1961), Oxford (1971) and Berlin (1977). Some organizational aspects, financial support and remarkable events like international prizes in field of plasma physics are given

  7. Guido von Pirquet: Austrian pioneer of astronautics

    Science.gov (United States)

    Sykora, F.

    1977-01-01

    The works of Guido von Pirquet, Austrian pioneer of rocketry, were assessed. Major emphasis was given to Pirquet's calculation of the route to Venus which in fact was followed by the first Russian rocket to Venus. Of interest also is Pirquet's valuable construction of a space station and his analysis of interstellar space flight.

  8. Ueberreste vorweltlicher Proboscidier von Java und Banka

    NARCIS (Netherlands)

    Martin, K.

    1884-01-01

    Junghuhn führte in seinem Werke über Java nur einen einzigen Wirbelthierrest, Carcharias megalodon, an (7, IV, pag. 97); es war ihm nicht gelungen bei seinem ersten Aufenthalte auf der Insel Reste von Säugethieren zu finden, so eifrig er auch darnach in den Höhlen des Tertiaergebirges suchte (7, IV,

  9. Ueber eine Anomalie von Acromitus flagellatus (Stiasny)

    NARCIS (Netherlands)

    Stiasny, G.

    1934-01-01

    Bei erneuter Durchsicht des reichhaltigen Materiales von Acromitus flagellatus (Stiasny) in der Scyphomedusen-Sammlung des Rijksmuseum van Natuurlijke Historie in Leiden (vergl. meine Mitteilungen daruber, 1920, Uebersichtstabelle III und 1921, p. 131/136) fand ich ein Exemplar, das eine

  10. Von Kalifornien nach Taxham / Katri Soe

    Index Scriptorium Estoniae

    Soe, Katri, 1971-

    2005-01-01

    Neljas osa magistritööst "Von Kalifornien nach Taxham: Formen und Strukturen der Kommunikation in Peter Handkes Romanen "Der kurze Brief zum langen Abschied" und "In einer dunklen Nacht ging ich aus meinem stillen Haus"" (Tartu, 2000. Juhendaja: Claus Sommerhage)

  11. Von der lernenden Region zur "Smart Region“

    OpenAIRE

    Poschwatta, Wolfgang

    2004-01-01

    Von der lernenden Region zur "Smart Region“ / M. Hilpert, W. Poschwatta. - In: Nabizadeh-Araghi, Nima : Auf dem Weg zur "Smart Region" : regionale Entwicklung am Beispiel der Pistazienproduktion im Iran. - Augsburg : Müllerdruck, 2004. - S. 5-9. - (Terra facta ; 2)

  12. Development of a low-temperature refrigerant on the basis of carbon dioxide; Entwicklung eines Tieftemperaturkaeltemittels auf Basis von Kohlendioxid

    Energy Technology Data Exchange (ETDEWEB)

    Goepfert, Tobias; Hesse, Ullrich [Technische Univ. Dresden (Germany). Bitzer-Stiftungsprofessur fuer Kaelte-, Kryo- und Kompressorentechnik

    2014-07-01

    With the help of known substance properties and derived calculation correlations the mixtures were identified on the basis of R744, which are suitable as a cryogenic refrigerant in the range -50 to -100 degrees Celsius. A prediction and assessment of the suitability of the mixtures is made and the still unknown material properties are shown, which are required for detailed evaluation. [German] Mit Hilfe von bekannten Stoffeigenschaften und abgeleiteten Berechnungskorrelationen wurden Gemische auf der Basis von R744 identifiziert, welche sich als Tieftemperaturkaeltemittel im Bereich von -50 bis -100 Grad Celsius eigenen. Es wird eine Prognose und Abschaetzung der Eignung der Stoffgemische vorgenommen und es werden die noch unbekannten Stoffeigenschaften dargestellt, die zur genauen Bewertung benoetigt werden.

  13. Wir zeigen andere Bilder von Frauen ...

    Directory of Open Access Journals (Sweden)

    Bettina Rulofs

    2010-03-01

    Full Text Available Der vorliegende Beitrag beleuchtet die Bedeutung der Geschlechterordnung im Prozess der sportmedialen Kommunikation. Im Kern geht es um die Frage, inwiefern im Prozess der medialen Vermittlung von Sport traditionelle Geschlechterstereotype aufrechterhalten werden oder Möglichkeiten der Irritation solcher Stereotype bestehen. Dazu werden verschiedene Ebenen des massenmedialen Kommunikationsprozesses in den Blick genommen: die Medienprodukte, die Öffentlichkeitsarbeit und Selbst-Präsentation der Sportler/innen, die Medienrezeption und die Herstellungsprozesse von Medien in den Sportredaktionen. This article illustrates the relevance of gender in processes of sports media communication. The question in focus is in what way traditional gender stereotypes are perpetuated in the process of media communication in sport and how such stereotypes can be irritated. Therefore different levels of mass media communication are considered: the media products, the public relations of athletes and the presentation of themselves as athletes, the media-reception and the production processes in sport departments of media institutions.

  14. von Neumann's hypothesis concerning coherent states

    International Nuclear Information System (INIS)

    Zak, J

    2003-01-01

    An orthonormal basis of modified coherent states is constructed. Each member of the basis is an infinite sum of coherent states on a von Neumann lattice. A single state is assigned to each unit cell of area h (Planck constant) in the phase plane. The uncertainties of the coordinate x and the square of the momentum p 2 for these states are shown to be similar to those for the usual coherent states. Expansions in the newly established set are discussed and it is shown that any function in the kq-representation can be written as a sum of two fixed kq-functions. Approximate commuting operators for x and p 2 are defined on a lattice in phase plane according to von Neumann's prescription. (leeter to the editor)

  15. Theodor von Grotthuss’ Contribution to Electrochemistry

    International Nuclear Information System (INIS)

    Pauliukaite, Rasa; Juodkazytė, Jurga; Ramanauskas, Rimantas

    2017-01-01

    Freiherr Christian Johann Dietrich Theodor von Grotthuss (1785-1822) lived and worked in Lithuania. Inspired by Volta's pile he proposed the first theory of water electrolysis, which was published in 1805 in Rome. Michael Faraday acknowledged T. Grotthuss for this theory in his further investigations of electrolysis processes. Having studied in Germany and France Grotthuss brought science to province by establishing his laboratory in Gedučiai village in his mother's real estate. Lithuanian scientists are proud that life of Theodor von Grotthuss was related to this country. Many events to remember this prominent scientist are organised in Vilnius and other places. His works and example provided a good basis for further development of electrochemical science in Lithuania. Grotthuss insights into the mechanism of proton transport still are of great relevance to such areas of modern science as membrane biochemistry, energy conversion and storage.

  16. Inattentional blindness and the von Restorff effect.

    Science.gov (United States)

    Schmidt, Stephen R; Schmidt, Constance R

    2015-02-01

    Sometimes we fail to notice distinctive or unusual items (inattentional blindness), while other times we remember distinctive items more than expected items (the von Restorff effect). A three-factor framework is presented and tested in two experiments in an attempt to reconcile these seemingly contradictory phenomena. Memory for different types of unexpected stimuli was tested after an easy or difficult Stroop color-naming task. Highly arousing taboo words were well remembered even when the difficult Stroop task limited attentional resources. However, a conceptual isolation effect was only observed when the nature of the category change was highlighted by the Stroop task, the Stroop task was easy, and/or the isolated targets enjoyed a retrieval advantage relative to comparison targets. As proposed in the three-factor framework, the arousing qualities of the stimuli, the attentional demands of the primary task, and the relevance of isolated features at encoding and retrieval combine to produce inattentional blindness and the von Restorff effect.

  17. Verbesserung der Symmetrie von Hirnaufnahmen entlang der Sagittalebene

    Science.gov (United States)

    Ens, Konstantin; Wenzel, Fabian; Fischer, Bernd

    Die lokale Symmetrie von Hirnscans entlang der Sagittalebene zu ermitteln und zu modizifieren, ist für eine Reihe neurologischer Anwendungen interessant. Beispielsweise kann der voxelweise Vergleich von rechter und linker Hirnhälfte nur dann Aufschluss über die Lokalisierung von Läsionen geben, wenn durch Transformation ein Hirnscan eine möglichst hohe Symmetrie aufweist. Ein weiteres Anwendungsgebiet ist die Visualisierung von medialen Hirnschnitten, für die die Trennfläche beider Hirnhälfte möglichst eben sein sollte. Diese Arbeit stellt die Entwicklung eines Verfahrens vor, mit dessen Hilfe die Symmetrie von Hirnaufnahmen entlang der Sagittalebene verbessert werden kann. Dies geschieht unter Verwendung von aktiven Konturen, die mit Hilfe einer neuartigen Kostenfunktion gesteuert werden. Experimente am Ende der Arbeit mit strukturellen Kernspinaufnahmen demonstrieren die Leistungsfähigkeit des Verfahrens.

  18. Rohlin flows on Von Neumann algebras

    CERN Document Server

    Masuda, Toshihiko

    2016-01-01

    The authors will classify Rohlin flows on von Neumann algebras up to strong cocycle conjugacy. This result provides alternative approaches to some preceding results such as Kawahigashi's classification of flows on the injective type II_1 factor, the classification of injective type III factors due to Connes, Krieger and Haagerup and the non-fullness of type III_0 factors. Several concrete examples are also studied.

  19. Marktorientierte Vertriebs-Reorganisation von Energieversorgungsunternehmen

    OpenAIRE

    Beutin, Nikolas; Scholl, Michael; Fürst, Andreas

    2003-01-01

    Seit der Liberalisierung des Energiemarktes im Jahre 1998 sehen sich Energieversorgungsunternehmen (EVUs) einer veränderten Markt- und Wettbewerbssituation gegenüber. Neben Risiken, wie dem Eintritt von Wettbewerbern in das vormals geschützte Gebiet, eröffnete sich ihnen hierdurch aber auch die Chance, außerhalb des eigenen Netzbereiches neue Kunden zu gewinnen. Um sowohl dem Margenverfall als auch der direkten Vergleichbarkeit mit ...

  20. La Medea de Lars von Trier

    Directory of Open Access Journals (Sweden)

    Iratxe Fresneda Delgado

    2013-04-01

    Full Text Available El presente artículo analiza el modo en el que Lars von Trier recrea para el cine el estereotipo de Medea. Mediante el análisis fílmico de la película y apoyándose en los estudios culturales, el texto se interroga acerca de la importancia y el poder potencial del cine a la hora recuperar el antiguo mito y demostrar su vigencia. El análisis amplía horizontes para la compresión de los mecanismos que articulan el entramado de significados de la película, donde Von Trier aporta una nueva visión del arquetipo de Medea uniéndola, a la tradición pictórica del Romanticismo. Una influencia que habita en las posteriores obras del director danés, donde el paisaje, la naturaleza, se erige en elemento catalizador de las pulsiones humanas, en su cómplice y testigo.This paper explores the way that Lars von Trier’s film recreates the stereotype of Medea. Using film analysis and based on cultural studies the article asks about the importance and potential power of cinema to recover the ancient myth and show their effects. The analysis expands horizons for the understanding of the mechanisms that link the network of meanings of the film, where the author offers a new vision of Medea's archetype attaching it to the pictorial tradition tied to the Romanticism. An influence that can be seen in the later works of Lars von Trier, where the landscape, the nature, stands as a catalyst of human drives, as his accomplice and witness.

  1. Visuelle Analyse von E-mail-Verkehr

    OpenAIRE

    Mansmann, Florian

    2003-01-01

    Diese Arbeit beschreibt Methoden zur visuellen geographischen Analyse von E-mail Verkehr.Aus dem Header einer E-mail können Hostadressen und IP-Adressen herausgefiltert werden. Anhand einer Datenbank werden diesen Host- und IP-Adressen geographische Koordinaten zugeordnet.Durch eine Visualisierung werden in übersichtlicher Art und Weise mehrere tausend E-mail Routen dargestellt. Zusätzlich dazu wurden interktive Manipulationsmöglichkeiten vorgestellt, welche eine visuelle Exploration der Date...

  2. Zur Kenntnis von Gnetum neglectum Bl

    NARCIS (Netherlands)

    Markgraf, F.

    1960-01-01

    Gnetum neglectum war nicht nur, wie der Name andeutet, bis zu Blumes Zeit übersehen worden, sondern es wurde von Späteren wiederum verkannt, wie ich in Bull. J. B. Buitenzorg 3. Ser. 10 (1930) 474 näher ausgeführt habe. Die echte Art taucht verhältnismässig selten in den Herbarien auf. Sie ist eine

  3. Von Medien, Übertragungen und Automaten

    Directory of Open Access Journals (Sweden)

    Alessandro Barberi

    2013-12-01

    Full Text Available Im Zuge der Debatten zum Medialen Habitus wurde vielfach betont, dass die >Theorie der Praxispraxeologischen Medientheorie< des Medialen Habitus avant la lettre gesprochen werden kann. Dieser Artikel untersucht – ausgehend von den Debatten zur "Medienkompetenz" – wie Bourdieu Sprache, Sprechen und Diskurs, sowie Akteure, Felder und Habitus als Medien begreift und betont dabei die Nützlichkeit der Bourdieuschen Bildungssoziologie im Rahmen einer sozialwissenschaftlichen Grundlegung der Medienpädagogik.

  4. Portrait of Dr. Von Braun with Walt Disney, 1954.

    Science.gov (United States)

    1954-01-01

    Marshall Center Director Dr. Wernher Von Braun is pictured with Walt Disney during a visit to the Marshall Space Flight Center in 1954. In the 1950s, Dr. Von Braun while working in California on the Saturn project, also worked with Disney studios as a technical director in making three films about Space Exploration for television. Disney's tour of Marshall in 1965 was Von Braun's hope for a renewed public interest in the future of the Space Program at NASA.

  5. Gespiegelte Planeten – Die Anordnung der Pyramiden von Gizeh

    OpenAIRE

    Jelitto, Hans

    2000-01-01

    Antike Bauwerke wurden wiederholt auf astronomische Zusammenhänge hin untersucht, so z. B. ihre Ausrichtung in Bezug auf die Bewegung von Sonne oder Sternen. Vor diesem Hintergrund wurden für die Pyramiden von Gizeh drei ungewöhnliche Gleichungen entdeckt, die die Pyramidengrößen mit einer Genauigkeit von ca. 0,1 % festlegen. Gleichzeitig legen diese drei Gleichungen nahe, die drei Pyramiden in der Reihenfolge Mykerinos-, Chefren- und Cheopspyramide den inneren drei Planeten unseres Sonnensys...

  6. Saage tuttavaks : Elisabeth ja Karl von Hoerschelmann / Mai Levin

    Index Scriptorium Estoniae

    Levin, Mai, 1942-

    2004-01-01

    Kuraator M. Levin kuni 10. X 2004 Adamson-Ericu muuseumis avatud näitusest "Tuntud ja tundmatud Elisabeth von Rosendorff-Hoerschelmann ja Karl von Hoerschelmann". Enamik töid on kunstnike laste Konstantin Hoerschelmanni ja Anna Röder-Hoerschelmanni omand. Elisabeth Rosendorff (1898-1984) sündis Virumaal Maidlas eesti perekonnas, Karl von Hoerschelmann (1899-1951) Sevastoopolis saksa perekonnas

  7. Arbeitszeiten von Professorinnen und Professoren in Deutschland 2016

    OpenAIRE

    Weihs, Claus; Hernández Rodríguez, Tanja; Doeckel, Maximilian; Marty, Christoph; Wormer, Holger

    2018-01-01

    In dieser Studie werden belastbare Prognoseintervalle der wöchentlichen Gesamtarbeitszeit von Universitätsprofessorinnen und -professoren aus Daten einer Umfrage aus dem Jahre 2016 und a-priori Informationen aus früheren Studien bestimmt. Neben der Gesamtarbeitszeit werden auch Teilarbeitszeiten zum Beispiel für Lehre und Forschung ermittelt. Die Ergebnisse von frequentistischer und Bayesianischer Analyse werden verglichen. Aus den gültigen Fragebögen von aktiven Vollzeit arbeitenden Universi...

  8. Untersuchungen zur Farbreaktion von Amilorid, Chlorhexidin und Proguanil mit Hypobromit

    OpenAIRE

    Huth, Silke

    2004-01-01

    Bei der Reaktion von Amiloridhydrochlorid (1· HCl) mit Brom in alkalischer Lösung wird ein gelbbraunes Dehydrierungsprodukt erhalten, daß als 3-(3-Amino-1,2,4-oxadiazol-5-yl)-5-chlor-2,6-pyrazindiamin (6) identifiziert werden konnte. Durch Vergleich von Massen- und NMR-Spektren der Verbindung 6 mit Spektren von 1· HCl und Referenzsubstanzen I-III konnte auf die verbindung 6 geschlossen werden. Die Struktur wurde durch eine Röntgenstrukturanalyse abgesichert. Erhitzen von Amiloridhydrochlorid ...

  9. Chancen und Gefahren von Global-Marketing-Konzepten

    OpenAIRE

    Berndt, Ulrike

    1990-01-01

    Chancen und Gefahren von Global-Marketing-Konzepten. - Augsburg : Förderges. Marketing, 1990. - 57, XII S. - Zugl: Augsburg, Univ., Diplomarb. - (Arbeitspapiere zur Schriftenreihe Schwerpunkt Marketing ; 29)

  10. A bicategorical approach to Morita equivalence for von Neumann algebras

    International Nuclear Information System (INIS)

    Brouwer, R. M.

    2003-01-01

    We relate Morita equivalence for von Neumann algebras to the ''Connes fusion'' tensor product between correspondences. In the purely algebraic setting, it is well known that rings are Morita equivalent if they are equivalent objects in a bicategory whose 1-cells are bimodules. We present a similar result for von Neumann algebras. We show that von Neumann algebras form a bicategory, having Connes's correspondences as 1-morphisms, and (bounded) intertwiners as 2-morphisms. Further, we prove that two von Neumann algebras are Morita equivalent iff they are equivalent objects in the bicategory. The proofs make extensive use of the Tomita-Takesaki modular theory

  11. Der Einfluß der Ablauforganisation auf die Effizienz von Entscheidungen: Eine empirische Untersuchung am Beispiel von Bilanzanalysen

    OpenAIRE

    Gemünden, Hans Georg

    1987-01-01

    Der vorliegende Beitrag widmet sich einem in der Organisationstheorie stark vernachlässigten Problem: der Ablauforganisation von Entscheidungen. Am Beispiel von Bilanzanalysen wird empirisch geprüft, in welcher Weise eine Gliederung des Prozesses nach Verrichtungen oder Objekten die Qualität der Analyse beeinflußt. Hierzu wird ein validiertes Konzept zur Messung der Qualität von Bilanzanalysen entwickelt. Es wird gezeigt, wie man mittels prozeßbegleitender experimenteller Organisationsforschu...

  12. Beeinflussung der Wirkung von Ernährungsinformation durch Framing: Analyse am Beispiel von Folsäure

    OpenAIRE

    Lensch, Kathrin; Hartmann, Monika; Simons, Johannes

    2011-01-01

    Die Bereitstellung und verbrauchergerechte Aufbereitung von Informationen stellt eine Möglichkeit dar, Konsumenten darin zu unterstützen, Gesundheitsaspekte vermehrt in das Kauf- und Essverhalten zu integrieren. In der Verhaltensökonomik gelten Framing-Effekte als wichtige Bestimmungsfaktoren für die Wahrnehmung von Informationen. Im Rahmen des vorliegenden Beitrags werden Framing-Effekte am Beispiel von Ernährungsinformationen über Folsäure mit Hilfe eines Experiments untersucht. Die Ergebni...

  13. Schelling, von Neumann, and the Event that Didn’t Occur

    Directory of Open Access Journals (Sweden)

    Alexander J. Field

    2014-02-01

    Full Text Available Thomas Schelling was recognized by the Nobel Prize committee as a pioneer in the application of game theory and rational choice analysis to problems of politics and international relations. However, although he makes frequent references in his writings to this approach, his main explorations and insights depend upon and require acknowledgment of its limitations. One of his principal concerns was how a country could engage in successful deterrence. If the behavioral assumptions that commonly underpin game theory are taken seriously and applied consistently, however, nuclear adversaries are almost certain to engage in devastating conflict, as John von Neumann forcefully asserted. The history of the last half century falsified von Neumann’s prediction, and the “event that didn’t occur” formed the subject of Schelling’s Nobel lecture. The answer to the question “why?” is the central concern of this paper.

  14. Philologie im Horizont der Geschichtlichkeit von Sprache und Text: zum Tagungsband von Wulf Oesterreicher und Maria Selig

    Directory of Open Access Journals (Sweden)

    Olaf Müller

    2016-03-01

    Full Text Available Wulf Oesterreicher und Maria Selig, Hrsg., Geschichtlichkeit von Sprache und Text: Philologien – Disziplingenese – Wissenschaftshistoriographie (Paderborn: Wilhelm Fink, 2014, 332 S.

  15. Von den Liven von Oesel / August Ludwig Schlözer

    Index Scriptorium Estoniae

    Schlözer, August Ludwig

    2008-01-01

    Avaldatud Eberhard Winkleri initsiatiivil A. L. Schlözeri teose põhjal: Gesammelte Nachrichten von den Ueberresten der Liven, in Livland und Kurland. (1770), mis moodustab osa teosest: Schlözer, August Ludwig. M. Johann Joseph Haigold's Beylagen zum Neuveränderten Russland. Zweiter Theil. Riga und Leipzig, 1770

  16. Aino Lepik von Wiren / Aino Lepik von Wiren ; interv. Kadi Alatalu

    Index Scriptorium Estoniae

    Lepik von Wirén, Aino, 1961-

    2007-01-01

    Heinrich Marga eksiilvalitsuse (20.06.1990-7.10.1992) kohtuminister Aino Lepik von Wiren pagulaslapse elust Rootsis, haridusest ja elukutse valikust, tööst eksiilvalitsuses, tööleasumisest Eestisse 1992. aastal, seadusandlikust tegevusest ning aluse panekust välismaalaste- ja kodakondsuspoliitikale, naiste võimalustest poliitilisse tippu tõusmiseks, kodu- ja väliseestlaste vastandamisest

  17. Ööklubi Club von Überlingen = Club von Überlingen

    Index Scriptorium Estoniae

    2008-01-01

    Ööklubi Club von Überlingen (Madara 22A, Tallinn) sisekujundusest. Sisearhitekt: Taavi Aunre (Boom.ee OÜ). Taavi Aunrest, tema tähtsamad tööd. I-II korruse plaan, 11 värv. vaadet, foto T. Aunrest

  18. Determination of microstructural parameters in damage models for ductile metals; Bestimmung von mikrostrukturellen Parametern in Schaedigungsmodellen fuer duktile Metalle

    Energy Technology Data Exchange (ETDEWEB)

    Steglich, D. [GKSS-Forschungszentrum Geesthacht GmbH (Germany). Inst. fuer Werkstofforschung

    1999-07-01

    For the determination of material parameters in micromechanical damage models the mechanical behaviour of representative volume elements of a two-phase material has been investigated and the phase morphology quantified by microstructural analysis. The material parameters have been successfully correlated to microstructural quantities and a prediction of the damage behaviour of structures is performed. Special emphasis is given to the model of Gurson, Tvergaard and Needleman, which has been used to predict the macroscopic behaviour of smooth tensile test specimens and the fracture resistance curves of bending specimens for two different materials, a nodular cast iron and a particle reinforced aluminium compound. (orig.) [German] Zur Bestimmung der Materialparameter in mikromechanischen Schaedigungsmodellen werden repraesentative Strukturelemente eines Werkstoffes untersucht und die Morphologie eines zweiphasigen Gefueges durch quantitative Gefuegeanalyse beschrieben. Mit dieser Strategie gelingen eine Identifikation der im Modell enthaltenen Parameter sowie die Vorhersage des Versagensverhaltens von Strukturen. Als mikromechanisches Materialmodell wird hauptsaechlich das Modell von Gurson, Tvergaard und Needleman verwendet. Seine Anwendbarkeit zur Vorhersage des globalen Verhaltens von glatten Zugproben und zur Simulation von Risswiderstandskurven wird bei zwei verschiedenen Werkstoffen gezeigt, einen Gusseisen und einem Aluminium-Verbundwerkstoff. (orig.)

  19. Polychaeten aus den Zoologischen Museen von Leiden und Amsterdam I

    NARCIS (Netherlands)

    Augener, H.

    1933-01-01

    In der vorliegenden Arbeit ist die Untersuchung eines sehr umfangreichen Polychaeten-Materials niedergelegt, das mir von Herrn Prof. Dr. E. D. van Oort in Leiden und Herrn Prof. Dr. L. F. de Beaufort in Amsterdam zur Bearbeitung übergeben wurde. Von diesem Material ist der dem Museum in Leiden

  20. [Hans Jakob Christoffel von Grimmelshausen. Saksa Simplicissimuse seiklused] / Meelis Friedenthal

    Index Scriptorium Estoniae

    Friedenthal, Meelis, 1973-

    2011-01-01

    Tutvustus: Grimmelshausen, Hans Jakob Christoffel von. Saksa Simplicissimuse seiklused, teisisõnu: ühe veidra vagabundi elulugu, kel Melchior Sternfels von Fuchshaim nimeks, et kus ja mis moel ta siia ilma sündis ning mida siin nägi, õppis, oma nahal tunda sai ja kannatas, nagu sellestki, miks ta siinsest ilmast vabatahtlikult loobub. [Tallinn] : Pegasus, c2010

  1. Von Neumann algebras as complemented subspaces of B(H)

    DEFF Research Database (Denmark)

    Christensen, Erik; Wang, Liguang

    2014-01-01

    Let M be a von Neumann algebra of type II1 which is also a complemented subspace of B( H). We establish an algebraic criterion, which ensures that M is an injective von Neumann algebra. As a corollary we show that if M is a complemented factor of type II1 on a Hilbert space H, then M is injective...

  2. An accurate von Neumann's law for three-dimensional foams

    NARCIS (Netherlands)

    Hilgenfeldt, Sascha; Kraynik, Andrew M.; Koehler, Stephan A.; Stone, Howard A.

    2001-01-01

    The diffusive coarsening of 2D soap froths is governed by von Neumann's law. A statistical version of this law for dry 3D foams has long been conjectured. A new derivation, based on a theorem by Minkowski, yields an explicit analytical von Neumann's law in 3D which is in very good agreement with

  3. Erfahrungen an der Schnittstelle von Medienarbeit und Praxisforschung

    Directory of Open Access Journals (Sweden)

    Peter Holzwarth

    2007-11-01

    Full Text Available Der Beitrag reflektiert die Verbindung von praktischer Medienarbeit und Forschung am Beispiel eines internationalen EU-Forschungsprojekts zum Thema Medien und Migration. Neben didaktischen Prinzipien und Konzepten für die aktive Medienarbeit im Forschungskontext geht es um die Kooperation von medienpädagogischer Begleitung (MB und wissenschaftlicher Begleitung (WB sowie um deren spezifische Kompetenzen.

  4. Die baltischen Kapitulationen von 1710 : Kontext, Wirkungen, Interpretationen / Marten Seppel

    Index Scriptorium Estoniae

    Seppel, Marten, 1979-

    2015-01-01

    Arvustus: Die baltischen Kapitulationen von 1710 : Kontext, Wirkungen, Interpretationen, hrsg. von Karsten Brüggemann, Mati Laur und Pärtel Piirimäe, Queleln und Studien zur baltischen Geschichte, Bd 23 (Köln u.a: Böhlau Verlag, 2014)

  5. [Precocious puberty and von Recklinghausen's disease].

    Science.gov (United States)

    Barg, Ewa; Wikiera, Beata; Basiak, Aleksander; Głab, Ewa

    2006-01-01

    Von Recklinghausen's disease belongs to a group of neurocutaneous syndromes and is characterised by skin, nerve and bone abnormalities. We present a case of von Recklinghausen's disease and precocious puberty in 7-year-old boy. At the age of three café au lait spots on the skin and an incranial tumour situated near the optic chiasm--qualified as inoperable--were discovered. At the age of 7 first signs of precocious puberty appeared (pubic hair P3 and enlargement of the testes (15 ml) and penis). Laboratory measurements included: LH 7.5 mIU/ml, FSH 1.1 mIU/ml, testosterone 183 ng/ml, assessment of bone age: 9 years. The response to LHRH stimulation was characteristic for true precocious puberty (LH 15.9 mIU/ml and FSH 1.5 mIU/ml after 30 minutes). The MRI of the brain showed a tumour of the suprasellar region with compression of pituitary stalk. True precocious puberty was diagnosed. Treatment with Diphereline was introduced. At present the boy is 9 years old and has been treated with Diphereline for 16 months. The volume of the testicles has decreased to 7 ml and loss of pubic hair was noted. The MRI does not show any progression in tumour growth. The authors would like to underline the need of close observation of children with von Reclinghausen disease with regard to possibility of uncovering true precocious puberty which is critical for rapid diagnosis and introduction of correct treatment.

  6. Unlawfulness of environmental zones; Rechtswidrigkeit von Umweltzonen

    Energy Technology Data Exchange (ETDEWEB)

    Balbach, Jan

    2016-07-01

    The author examines the new findings on the effectiveness of the environmental zones and, in this context, questions their legitimacy. In addition, the efforts of the European and German legislators are analyzed in order to reduce the particulate matter pollution. In addition, legal protection against the exceeding of limits for particulate matter is critically appreciated. [German] Der Autor beleuchtet die neuen Erkenntnisse zur Wirksamkeit der Umweltzonen und hinterfragt vor diesem Hintergrund deren Rechtmaessigkeit. Darueber hinaus werden die Bemuehungen des europaeischen und deutschen Gesetzgebers analysiert, um die Feinstaubbelastung zu senken. Zudem wird der Rechtsschutz gegen die Ueberschreitung von Feinstaubgrenzwerten kritisch gewuerdigt.

  7. A Metabiography of Alexander von Humboldt

    Directory of Open Access Journals (Sweden)

    Nicolaas A. Rupke

    2006-04-01

    Full Text Available Article in English.The author's recently published monograph on Alexander von Humboldt describes the multiple images of this great cultural icon. The book is a metabiographical study that shows how from the middle of the nineteenth century to the present day Humboldt has served as a nucleus of crystallisation for a variety of successive socio-political ideologies, each producing its own distinctive representation of him. The historiographical implications of this biographical diversity are profound and support current attempts to understand historical scholarship in terms of memory cultures.

  8. Die Biopsie von Knochen- und Weichteiltumoren

    OpenAIRE

    Fuchs, B

    2008-01-01

    Technisch stellt die Biopsie von Knochen- und Weichteiltumoren einen simplen Akt dar, intellektuell aber ist die Planung einer Biopsie höchst anspruchsvoll. Zu häufig werden heutzutage immer noch Biopsien unsachgemäss durchgeführt, so dass die Behandlung - im besten Fall - erschwert wird. Eine unsachgemäss durchgeführte Biopsie führt häufig zu negativen funktionellen Konsequenzen für den Patienten, im schlimmsten Fall kann es die Prognose direkt beeinträchtigen. Aus diesem Grund soll...

  9. Die Altäre von Selinunt

    OpenAIRE

    Voigts, Clemens

    2014-01-01

    In der Dissertation wurden die Altäre von Selinunt, einer griechischen Kolonie auf Sizilien, mit den Methoden der Bauforschung untersucht. Die neun behandelten Brandopferaltäre sind monumentale Quaderbauten, die bis zu 20 m Länge erreichen. Sie stammen aus der Blütezeit Selinunts, dem 6. und 5. Jh. v. Chr. Die Bauten waren bereits im 19. und 20. Jh. freigelegt worden und wurden nun in Bauaufnahmen dokumentiert, zeichnerisch rekonstruiert und zeitlich eingeordnet. Dabei ließ sich an ihnen eine...

  10. Alexander von Humboldt’s footnotes

    OpenAIRE

    Werner, Anja

    2015-01-01

    Alexander von Humboldts Fußnoten waren ihrer Zeit weit voraus, obwohl sie kaum den heutigen akademischen Standards entsprechen. Dieser Artikel untersucht die Fußnoten in Humboldts Essai politique sur l‘île de Cuba (1826). Zwar ist es nicht immer leicht, die manchmal recht geheimnisvollen Verweise zu entschlüsseln, dennoch lohnt sich der Versuch: Humboldts Fußnoten geben nicht nur Auskunft über seine umfassenden Netzwerke des Wissens. Sie verweisen auch auf Auseinandersetzungen verschiedener G...

  11. [Heinz von zur Mühlen. Das Bürgertum Fordert Blut. Ein Bolschewistiches Flugblatt von 1918] / Paul Kaegbein

    Index Scriptorium Estoniae

    Kaegbein, Paul

    2007-01-01

    Arvustus: Heinz von zur Mühlen. Das Bürgertum Fordert Blut. Ein Bolschewistiches Flugblatt von 1918. In : Ostseeprovinzen, baltische Staaten und das Nationale. Münster : LIT, 2005, lk. 403-414. 1918. aastast pärit lendlehest, mille käekirja järgi otsustades on kirjutanud Viktor Kingissepp

  12. Guy von Dardel 1919-2009

    CERN Multimedia

    2009-01-01

    Guy von Dardel, a well-known figure at CERN and in the international particle physics community, passed away on 28 August. Guy von Dardel came to CERN when it was founded in 1954 and was a full-time staff member until 1964, performing several experiments and working on technical developments. These included the first measurement of the neutral pion’s life-time. Called to Lund University in 1964, he became professor there in 1965 and director of the 1.2 GeV electron accelerator. In the late 1960s, he performed an experiment at CERN’s PS that measured the decays of the Λ. Then, in the early 1970s, he involved the Lund group in a series of experiments at the Intersecting Storage Rings (ISR), where he measured the production of various types of particles. In particular, he participated in a series of experiments that observed the production of a high abundance of particles with large transverse momenta. This required an explanation...

  13. Die Krakauer Kirche von Karmeliten und Karmelitaninnen

    Directory of Open Access Journals (Sweden)

    Józef Szymon Wronski

    2004-12-01

    Full Text Available 1. Die Klosterkirche der unbeschuhten Karmelitinnen Zum Heiligen Josef. Ein glücklicher Auftakt und somit die charakteristische Einführung in das 20. Jh. für den Kirchenbau von Krakau war die Errichtung der Karmeliterinnen St. Josephs-Kirche an der Lobzowska-Straße 40, in der die Architekten (Tadeusz Stryjeński (1849-1943 - Projektant der Kirche und Franciszek Mączyński (1874-1947 - Ausführer des Bauprojektes mit eigenen Verbesserungen die historisch- eklektizistischen Formen d.h. die mittelalterlichen Formen vor allem des sog. Übergangsstils vereinfachten. Die Kirche, die in den Jahren 1903-1905 errichtet wurde, steht inmitten vom Baukomplex des Klosters, dessen Grundriss das Quadrat ist49. Der Kirchenbau ist ein dem Gesamtbau des Klosters eingefügter Längsraum. Hinter dem Chor liegt das Oratorium des Konvents. Das Material Backstein (mit Verwendung von Stein erinnert an die Baukunst eines der besten Architekten jener Zeit, nämlich Teodor Talowskis (1857-1910, der viele Kirchen in Südpolen, aber auch viele Bürgerhäuser nicht nur in Krakau im ausgehenden 19. Jh. baute. Die Architektur der Karmeliterinnen St. Josephs-Kirche ist immer noch im Malerischen begriffen. Aber die Vereinfachung der historischen Formen führt zu ihrer „Beruhigung” und dadurch zur Wuchtigkeit des Ausdrucks. Bemerkenswert ist die in dieser Zeit (in der Anlage noch seltene ausgewogene Proportionierung des Baukörpers. Das methodische Prinzip jener Zeit ist der Kontrast. Im Kontrast zu den gedrungenen und wuchtigen Formen des Baukörpers stehen z.B. die sich verjüngenden obeliskenförmigen und pylonenartigen Türmchen, die nicht nur die Eingangsfassade der Kirche flankieren, sondern auch an den Ecken des Querhauses der Kirche stehen. Die ingravierten weißen Steine an der Fassade in der Zahl von Zehn erinnern an das Gebot des Karmelterinnenordens: Bete täglich den Rosenkranz und sind zugleich ein Vanitativmotiv. 2. Die Klosterkirche der unbeschuhten

  14. Suitability of tracers; Eignung von Tracern

    Energy Technology Data Exchange (ETDEWEB)

    Klotz, D. [GSF - Forschungszentrum fuer Umwelt und Gesundheit GmbH, Neuherberg (Germany). Inst. fuer Hydrologie

    1999-02-01

    Hydrological tracer techniques are a means of making statements on the direction and speed of underground water. One of the simpler tasks is to find out whether there is hydrological communication between two given points. This requires a determination of the direction of flow, which places less exacting demands on the properties of the tracer than does the task of determining the flow velocity of underground water. Tracer methods can serve to infer from flow velocity the distance (flow) velocity, which is defined as the ratio between the distance between two points located in flow direction and the actual time it takes water to flow from one to the other. [Deutsch] Mit Hilfe der hydrologischen Markierungstechniken koennen Aussagen ueber die Richtung und die Geschwindigkeit von Bewegungen des unterirdischen Wassers gemacht werden. Der einfachere Fall liegt vor, wenn festgestellt werden soll, ob zwischen zwei Punkten eine hydrologische Verbindung besteht. Bei dieser Fliessrichtungsbestimmung sind die Forderungen an die Eigenschaften der einzusetzenden Tracer geringer als bei der Bestimmung der Geschwindigkeit des unterirdischen Wassers. Von den Geschwindigkeiten des unterirdischen Wassers ist die Abstands-(Fliess)geschwindigkeit, die definiert ist durch das Verhaeltnis aus dem Abstand und der wahren Fliesszeit zwischen zwei in Bewegungsrichtung gelegenen Punkten, durch Tracermethoden zu bestimmen. (orig.)

  15. Kontextualisierung von Queer Theory Contextualizing Queer Theory

    Directory of Open Access Journals (Sweden)

    Anna Voigt

    2008-03-01

    Full Text Available Christine M. Klapeer legt in diesem Einführungsband dar, aus welchen politischen und theoretischen Kontexten heraus sich ‚queer‘ zu einem Begriff mit besonderem politischem und theoretischem Gehalt entwickelt hat. Wesentlich zielt sie dabei auf eine kritische Kontextualisierung von „queer theory”. Die Autorin geht zunächst auf das Gay Liberation Movement ein, grenzt die Queer Theory vom Poststrukturalismus, von feministischen Theorien und den Lesbian and Gay Studies ab, beleuchtet Eckpunkte queeren Denkens und zeichnet schließlich die Entwicklungen in Österreich sowohl politisch-rechtlich als auch bewegungsgeschichtlich und in der Wissenschaftslandschaft nach.Christine M. Klapeer’s introductory volume demonstrates the manner in which ‘queer’ grew out of various political and theoretical contexts to become a term with special political and theoretical content. She focuses primarily on a critical contextualization of “queer theory.” The author begins by approaching the Gay Liberation Movement and then distinguishes Queer Theory from poststructuralism, from feminist theories, and from Lesbian and Gay Studies. She continues on to illuminate the key aspects of queer thought and concludes by sketching the development in Austria in terms of politics and the law, the history of movements, and within the landscape of knowledge.

  16. Catalytic cleaning of automotive exhaust gases; Katalytische Reinigung von Kraftfahrzeugabgasen

    Energy Technology Data Exchange (ETDEWEB)

    Domesle, R [Degussa AG, Hanau (Germany)

    1998-12-31

    In the Clean Air Act of 1970 the US American Government set itself the goal of reducing pollutant emissions from automobiles to 10% of the original level. While it was very ambitious at the time, this goal has meanwhile been reached, at least in terms of the amount of pollution per vehicle. The period between 1981 and 1986 alone saw emission reductions in the USA of 65% for CO, 60% for HC, and 40% for NO{sub x}. The introduction of stringent limit values in Europe is in particular predicted to bring about drastic reductions in HC emissions. By the year 2010, after the phase-out of old vehicles without a cat, HC emissions are expected to have decreased to 20% of the 1990 level. A similar development has been predicted for CO emissions. As for NO{sub x} emissions there will at least be drastic reductions in spark ignition vehicles. However, this success will be neutralised for some part by the growing number of diesel vehicles and by increasing mileage. These figures show impressively that the use of catalytic converters in road vehicles has made a substantial contribution to relieving the environment and improving the quality of life and will continue to do so in future. [Deutsch] Die amerikanische Regierung trat 1970 im Clean Air Act mit der Vorgabe an, die Schadstoffe aus Kraftfahrzeugen auf 10% des urspruenglichen Wertes mindern zu wollen. Dieses Ziel war zum damaligen Zeitpunkt sehr hochgesteckt, ist aber inzwischen erreicht worden, was die Schadstoffmenge pro Fahrzeug angeht. Allein zwischen den Jahren 1981-86 wurde eine Schadstoffreduzierung um 65% fuer CO, 60% fuer HC und 40% fuer NO{sub x} in den USA festgestellt. Durch Einfuehrung der strengen Grenzwerte in Europa ist vor allem eine drastische Verminderung der HC-Emissionen prognostiziert. Diese sollen im Jahre 2010 nach Auslaufen der Altfahrzeuge ohne Katalysator noch 20% des Niveaus von 1990 betragen. Fuer CO werden aehnliche Verhaeltnisse erwartet. Bei den NO{sub x}-Emissionen wird im PKW-Bereich fuer

  17. Catalytic cleaning of automotive exhaust gases; Katalytische Reinigung von Kraftfahrzeugabgasen

    Energy Technology Data Exchange (ETDEWEB)

    Domesle, R. [Degussa AG, Hanau (Germany)

    1997-12-31

    In the Clean Air Act of 1970 the US American Government set itself the goal of reducing pollutant emissions from automobiles to 10% of the original level. While it was very ambitious at the time, this goal has meanwhile been reached, at least in terms of the amount of pollution per vehicle. The period between 1981 and 1986 alone saw emission reductions in the USA of 65% for CO, 60% for HC, and 40% for NO{sub x}. The introduction of stringent limit values in Europe is in particular predicted to bring about drastic reductions in HC emissions. By the year 2010, after the phase-out of old vehicles without a cat, HC emissions are expected to have decreased to 20% of the 1990 level. A similar development has been predicted for CO emissions. As for NO{sub x} emissions there will at least be drastic reductions in spark ignition vehicles. However, this success will be neutralised for some part by the growing number of diesel vehicles and by increasing mileage. These figures show impressively that the use of catalytic converters in road vehicles has made a substantial contribution to relieving the environment and improving the quality of life and will continue to do so in future. [Deutsch] Die amerikanische Regierung trat 1970 im Clean Air Act mit der Vorgabe an, die Schadstoffe aus Kraftfahrzeugen auf 10% des urspruenglichen Wertes mindern zu wollen. Dieses Ziel war zum damaligen Zeitpunkt sehr hochgesteckt, ist aber inzwischen erreicht worden, was die Schadstoffmenge pro Fahrzeug angeht. Allein zwischen den Jahren 1981-86 wurde eine Schadstoffreduzierung um 65% fuer CO, 60% fuer HC und 40% fuer NO{sub x} in den USA festgestellt. Durch Einfuehrung der strengen Grenzwerte in Europa ist vor allem eine drastische Verminderung der HC-Emissionen prognostiziert. Diese sollen im Jahre 2010 nach Auslaufen der Altfahrzeuge ohne Katalysator noch 20% des Niveaus von 1990 betragen. Fuer CO werden aehnliche Verhaeltnisse erwartet. Bei den NO{sub x}-Emissionen wird im PKW-Bereich fuer

  18. Ludwig Leichhardt und Alexander von Humboldt

    Directory of Open Access Journals (Sweden)

    Aliya-Katarina Südfels

    2012-10-01

    Full Text Available Zusammenfassung Im Juli des Jahres 1841 kommt es zu einem Treffen zwischen zwei Männern, das zunächst belanglos erscheint, sich aber Jahre später als wichtige historische Begebenheit herausstellen wird. In seinem Pariser Büro empfängt der 71jährige Naturforscher Alexander von Humboldt den jungen Preußen Ludwig Leichhardt. Der angehende Naturwissenschaftler erhofft sich Zuspruch und Empfehlung des berühmten Alexander von Humboldts. Die Unterredung ist kurz und verläuft für Leichhardt ergebnislos. Es wird das einzige Treffen der beiden Naturwissenschaftler bleiben. Aus heutiger Sicht unverständlich, da Ludwig Leichhardt und Alexander von Humboldt mehr verband, als ihre Leidenschaft für die Naturwissenschaften. Viel zu wenig ist sich bis jetzt den biographischen Analogien und den vergleichbaren geographischen Leistungen der beiden Preußen gewidmet worden. Abstract During July 1841 a meeting between two men takes place, which seems to have been extraneous, but turns out to be a significant historical incident. 71 year old natural scientist Alexander von Humboldt welcomes young Ludwig Leichhardt from Prussia in his office in Paris. The prospective young scientist expects help and references from famous Alexander von Humboldt. The conversation is short and ends from Leichhardt’s point of view without results. Unfortunately this is going to be the only meeting between the two scientists even though the two Prussians have more in common than their passion for the natural sciences. Way too seldomly have biographical analogy and geographical productivity of the two men been compared. Résumé En juillet 1841 une rencontre entre deux hommes a lieu, qui au premier abord semble sans importance, mais qui des années plus tard est considéré comme un événement historique majeur. Dans son bureau parisien, le naturaliste Alexandre de Humboldt, alors âgé de 71 ans, reçoit le jeune Prussien Ludwig Leichhardt. Le jeune scientifique en devenir

  19. CD31-Expression am Primärtumor und Nachweis hämatogen disseminierter Tumorzellen im Knochenmark von Brustkrebspatientinnen

    OpenAIRE

    Eisenmann, Petra

    2005-01-01

    Der Nachweis von disseminierten Tumorzellen im Knochenmark von Patientinnen mit primärem Mammakarzinom ist ein wichtiger prognostischer Parameter. In der vorliegenden Arbeit wurde der Nachweis von CD31 am Primärtumor Mammakarzinom mit dem Auftreten von Mikrometastasen im Knochenmark korreliert. Ferner wurde die prognostische Bedeutung von disseminierten Tumorzellen im Knochenmark und die prognostische Bedeutung von CD31 evaluiert. Bei 50 Patientinnen des Gesamtkollektivs von 195 (25,6%) wu...

  20. A Buffer Model Account of Behavioral and ERP Patterns in the Von Restorff Paradigm

    Directory of Open Access Journals (Sweden)

    Siri-Maria Kamp

    2016-06-01

    Full Text Available We combined a mechanistic model of episodic encoding with theories on the functional significance of two event-related potential (ERP components to develop an integrated account for the Von Restorff effect, which refers to the enhanced recall probability for an item that deviates in some feature from other items in its study list. The buffer model of Lehman and Malmberg (2009, 2013 can account for this effect such that items encountered during encoding enter an episodic buffer where they are actively rehearsed. When a deviant item is encountered, in order to re-allocate encoding resources towards this item the buffer is emptied from its prior content, a process labeled “compartmentalization”. Based on theories on their functional significance, the P300 component of the ERP may co-occur with this hypothesized compartmentalization process, while the frontal slow wave may index rehearsal. We derived predictions from this integrated model for output patterns in free recall, systematic variance in ERP components, as well as associations between the two types of measures in a dataset of 45 participants who studied and freely recalled lists of the Von Restorff type. Our major predictions were confirmed and the behavioral and physiological results were consistent with the predictions derived from the model. These findings demonstrate that constraining mechanistic models of episodic memory with brain activity patterns and generating predictions for relationships between brain activity and behavior can lead to novel insights into the relationship between the brain, the mind, and behavior.

  1. Clarifying the link between von Neumann and thermodynamic entropies

    Science.gov (United States)

    Deville, Alain; Deville, Yannick

    2013-01-01

    The state of a quantum system being described by a density operator ρ, quantum statistical mechanics calls the quantity - kTr( ρln ρ), introduced by von Neumann, its von Neumann or statistical entropy. A 1999 Shenker's paper initiated a debate about its link with the entropy of phenomenological thermodynamics. Referring to Gibbs's and von Neumann's founding texts, we replace von Neumann's 1932 contribution in its historical context, after Gibbs's 1902 treatise and before the creation of the information entropy concept, which places boundaries into the debate. Reexamining von Neumann's reasoning, we stress that the part of his reasoning implied in the debate mainly uses thermodynamics, not quantum mechanics, and identify two implicit postulates. We thoroughly examine Shenker's and ensuing papers, insisting upon the presence of open thermodynamical subsystems, imposing us the use of the chemical potential concept. We briefly mention Landau's approach to the quantum entropy. On the whole, it is shown that von Neumann's viewpoint is right, and why Shenker's claim that von Neumann entropy "is not the quantum-mechanical correlate of thermodynamic entropy" can't be retained.

  2. Die Rolle von RANK-Ligand und Osteoprotegerin bei Osteoporose

    Directory of Open Access Journals (Sweden)

    Hofbauer LC

    2004-01-01

    Full Text Available Receptor activator of nuclear factor (NF- κB ligand (RANKL, sein zellulärer Rezeptor RANK und der Decoy-Rezeptor Osteoprotegerin (OPG stellen ein essentielles Zytokinsystem für die Zellbiologie von Osteoklasten dar. Verschiedene Untersuchungen belegen die Bedeutung von Störungen des OPG/RANKL/RANK-Systems bei der Pathogenese metabolischer Knochenerkrankungen. In dieser Arbeit werden die wichtigsten Störungen des OPG/RANKL/RANK-Systems bei verschiedenen Osteoporoseformen dargestellt. Östrogenrezeptor- (ER- Agonisten wie 17 β-Östradiol, Raloxifen und Genistein stimulieren die osteoblastäre Produktion von OPG durch Aktivierung von ER- α in vitro, während Lymphozyten von Patientinnen mit Östrogenmangel RANKL überexprimieren. Die parenterale Gabe von OPG vermag den mit Östrogenmangel assoziierten Knochenverlust im Tiermodell und in einer kleineren klinischen Studie zu verhindern. Glukokortikoide und Immunsuppressiva steigern gleichzeitig die RANKL-Expression und hemmen die OPG-Produktion in osteoblastären Zellen in vitro. Glukokortikoide sind auch in vivo imstande, die OPG-Serumspiegel deutlich zu reduzieren. Dagegen hemmen biomechanische Reize in vitro die RANKL-Produktion und steigern die OPG-Produktion. Ein Fehlen dieser biomechanischen Reize bei längerer Immobilisierung kann daher den RANKL/OPG-Quotienten steigern, während die tierexperimentelle Immobilisierungs-Osteoporose durch die parenterale Gabe von OPG gemildert werden kann.

  3. Prediction of the pharmacological effect of octreotide in acromegaly by means of {sup 111}In-pentetreotide scintigraphy and calculation of a pituitary uptake index; Praediktion der pharmakologischen Wirkung von Octreotid bei Akromegalie mittels {sup 111}In-Pentetreotid-Szintigraphie und Berechnung eines hypophysaeren Uptake-Index

    Energy Technology Data Exchange (ETDEWEB)

    Goerges, R. [Mainz Univ. (Germany). Klinik und Poliklinik fuer Nuklearmedizin; Cordes, U. [Arbeitsgemeinschaft Niedergelassener Endokrinologen, Mainz/Darmstadt (Germany); Engelbach, M. [Mainz Univ. (Germany). III. Medizinische Klinik und Poliklinik; Bartelt, K.M. [Arbeitsgemeinschaft Niedergelassener Endokrinologen, Mainz/Darmstadt (Germany); Haberern, G. [Mainz Univ. (Germany). Klinik und Poliklinik fuer Nuklearmedizin; Hey, O. [Mainz Univ. (Germany). Neurochirurgische Klinik und Poliklinik; Beyer, J. [Mainz Univ. (Germany). III. Medizinische Klinik und Poliklinik; Bockisch, A. [Mainz Univ. (Germany). Klinik und Poliklinik fuer Nuklearmedizin

    1997-06-01

    Aim: The aim of our prospective study was to optimize the determination of the pituitary somatostatin receptor status by means of 111-In-pentetreotide scintigraphy and to compare it intraindividually with the pharmacological effect of octreotide in active acromegaly. Methods: In n=22 patients with growth hormone (GH) secreting pituitary adenoma, 111-In-penetreotide scintigraphy was performed, and the specific radionuclide accumulation in the pituitary area (evaluation visually as well as semiquantitatively by means of ROI technique and calculation of various uptake indices) was correlated with the acute drop of GH after administration of 100 {mu}g octreotide s.c. (octreotide acute test). Results: The uptake index we propose (cts/pixel-ratio circular pituitary ROI: Irregular cerebrum ROI after background correction in the sagittal SPECT slice with maximum pituitary uptake 24 h p.i.) correlates best with the pharmacological effect (acute decrease of GH levels) of octreotide; its upper normal limit amounts of 3.5. Conclusion: As often the normal pituitary gland can be visualized scintigraphically, the purely visual differentiation between a normal and pathological receptor status sometimes is equivocal. A pituitary uptake index, calculated by means of a standardized ROI technique, facilitates this discrimination and so contributes to select possible responders for a treatment with octreotide. (orig.) [Deutsch] Ziel: Ziel unserer prospektiven Studie war die optimierte Bestimmung des hypophysaeren Somatostatin-Rezeptorstatus in der 111-In-Pentetreotid-Szintigraphie und der intraindividuelle Vergleich mit dem pharmakologischen Effekt von Octreotid bei florider Akromegalie. Methoden: Bei n=22 Patienten mit Wachstumshormon-(GH)-sezernierendem Hypophysenadenom wurde eine 111-In-Pentetreotid-Szintigraphie durchgefuehrt und die spezifische Nuklidakkumulation in der Hypophysenregion (Auswertung sowohl visuell als auch semiquantitativ mittels ROI-Technik und Berechnung

  4. Das Geschäftsmodell von Retail Banken im Wandel der Digitalisierung

    OpenAIRE

    Messikommer, Cédric

    2016-01-01

    Der Prozess der Digitalisierung führt in unterschiedlichen Branchen zu tiefgreifenden Veränderungen. Dazu gehört auch der Finanzsektor, dessen Umfeld von erodierenden Margen und Tiefstzinsen geprägt ist. Die Digitalisierung hat weitreichende Auswirkungen auf die Geschäftsmodelle von Banken und speziell von Retail Banken. Deren Basisdienstleistungen werden zunehmend von neuen Mitbewerbern mit modernster Internet-Technologie angeboten. Damit sind wesentliche Teile der Wertschöpfungskette von Re...

  5. Strukturbasierte Entwicklung von Assaysystemen und Charakterisierung von orthosterischen und allosterischen Kinaseinhibitoren

    OpenAIRE

    Klüter, Sabine

    2010-01-01

    Die Proteinkinasen stellen eine wichtige Enzymklasse für die Regulation der Signaltransduktion dar. Sie steuern diese diffizil regulierten, intrazellulären Signalkaskaden durch Übertragung der ?-Phosphatgruppe von ATP auf andere Proteine. Fehlregulationen dieser komplexen Stoffwechselwege können Krankheiten wie Krebs, Diabetes oder Autoimunkrankheiten verursachen. Somit gehören die Kinasen in den letzten Jahren zu den wichtigsten Zielproteinen der Pharmaindustrie. Die klassi...

  6. Der Effekt von Akupunktur in der Prävention von Prüfungsangst

    OpenAIRE

    Krüger, Peter

    2017-01-01

    Prüfungsangst ist ein weit verbreitetes gesellschaftliches Phänomen, das bisher in nur wenigen wissenschaftlichen Ansätzen untersucht wurde. Die Zahl der Studenten, die Gehirn - Doping zur Leistungssteigerung und zur Minimierung von Prüfungsangst nutzen, steigt stetig an. In bisherigen Studien wurde Akupunktur an Herz 7 als vielversprechende Behandlungsalternative dargestellt. Basierend auf diesen Ergebnissen, wurde in dieser Arbeit untersucht, ob eine Einzelpunktakupunktur an Herz 7 die ...

  7. The VITRO Score (Von Willebrand Factor Antigen/Thrombocyte Ratio as a New Marker for Clinically Significant Portal Hypertension in Comparison to Other Non-Invasive Parameters of Fibrosis Including ELF Test.

    Directory of Open Access Journals (Sweden)

    Stephanie Hametner

    Full Text Available Clinically significant portal hypertension (CSPH, defined as hepatic venous pressure gradient (HVPG ≥10 mmHg, causes major complications. HVPG is not always available, so a non-invasive tool to diagnose CSPH would be useful. VWF-Ag can be used to diagnose. Using the VITRO score (the VWF-Ag/platelet ratio instead of VWF-Ag itself improves the diagnostic accuracy of detecting cirrhosis/ fibrosis in HCV patients.This study tested the diagnostic accuracy of VITRO score detecting CSPH compared to HVPG measurement.All patients underwent HVPG testing and were categorised as CSPH or no CSPH. The following patient data were determined: CPS, D'Amico stage, VITRO score, APRI and transient elastography (TE.The analysis included 236 patients; 170 (72% were male, and the median age was 57.9 (35.2-76.3; 95% CI. Disease aetiology included ALD (39.4%, HCV (23.4%, NASH (12.3%, other (8.1% and unknown (11.9%. The CPS showed 140 patients (59.3% with CPS A; 56 (23.7% with CPS B; and 18 (7.6% with CPS C. 136 patients (57.6% had compensated and 100 (42.4% had decompensated cirrhosis; 83.9% had HVPG ≥10 mmHg. The VWF-Ag and the VITRO score increased significantly with worsening HVPG categories (P<0.0001. ROC analysis was performed for the detection of CSPH and showed AUC values of 0.92 for TE, 0.86 for VITRO score, 0.79 for VWF-Ag, 0.68 for ELF and 0.62 for APRI.The VITRO score is an easy way to diagnose CSPH independently of CPS in routine clinical work and may improve the management of patients with cirrhosis.

  8. [Albert Reder Ritter von Schellmann (1826-1904)].

    Science.gov (United States)

    Schmidt, G; Holubar, K

    1990-01-01

    Albert Reder von Schellmann (1826-1904) was an important syphilidologist of the Vienna Medical School in the second half of the nineteenth century. He went in for the dualistic concept of the origin of syphilis and ulcer caused by soft chancre. In 1870 - Reder became head of a third dermato-syphilidologic department in the "Josephinum" in Vienna, where military surgeons got their medical education. At the same time the two full professorships of dermatosyphilidology in the Vienna General Hospital were held by Ferdinand von Hebra (1816-1880) and Carl Ludwig Sigmund von Ilanor (1810-1883).

  9. Speziation von Gadolinium-MRT-Kontrastmitteln in Umweltmatrizes

    OpenAIRE

    Lindner, Uwe

    2017-01-01

    Gd-Kontrastmittel werden in der Medizin für die Magnetresonanztomographie (MRT) benötigt, um einen besseren Bildkontrast zu erzielen. Nach der Anwendung gelangen diese Arzneimittel über das Abwasser in die Klärwerke und von dort in die jeweiligen anliegenden Oberflächengewässer. Somit wird es notwendig, den Verbleib der Gd-MRT-Kontrastmittel in der Umwelt zu verfolgen und aufzuklären. In dieser Arbeit werden für die Analyse von Umweltproben Methoden zur Speziesanalytik von Gd-Kontrastmitteln ...

  10. Biomarkers of Host Response Predict Primary End-Point Radiological Pneumonia in Tanzanian Children with Clinical Pneumonia: A Prospective Cohort Study.

    Directory of Open Access Journals (Sweden)

    Laura K Erdman

    Full Text Available Diagnosing pediatric pneumonia is challenging in low-resource settings. The World Health Organization (WHO has defined primary end-point radiological pneumonia for use in epidemiological and vaccine studies. However, radiography requires expertise and is often inaccessible. We hypothesized that plasma biomarkers of inflammation and endothelial activation may be useful surrogates for end-point pneumonia, and may provide insight into its biological significance.We studied children with WHO-defined clinical pneumonia (n = 155 within a prospective cohort of 1,005 consecutive febrile children presenting to Tanzanian outpatient clinics. Based on x-ray findings, participants were categorized as primary end-point pneumonia (n = 30, other infiltrates (n = 31, or normal chest x-ray (n = 94. Plasma levels of 7 host response biomarkers at presentation were measured by ELISA. Associations between biomarker levels and radiological findings were assessed by Kruskal-Wallis test and multivariable logistic regression. Biomarker ability to predict radiological findings was evaluated using receiver operating characteristic curve analysis and Classification and Regression Tree analysis.Compared to children with normal x-ray, children with end-point pneumonia had significantly higher C-reactive protein, procalcitonin and Chitinase 3-like-1, while those with other infiltrates had elevated procalcitonin and von Willebrand Factor and decreased soluble Tie-2 and endoglin. Clinical variables were not predictive of radiological findings. Classification and Regression Tree analysis generated multi-marker models with improved performance over single markers for discriminating between groups. A model based on C-reactive protein and Chitinase 3-like-1 discriminated between end-point pneumonia and non-end-point pneumonia with 93.3% sensitivity (95% confidence interval 76.5-98.8, 80.8% specificity (72.6-87.1, positive likelihood ratio 4.9 (3.4-7.1, negative likelihood ratio 0

  11. Biomarkers of Host Response Predict Primary End-Point Radiological Pneumonia in Tanzanian Children with Clinical Pneumonia: A Prospective Cohort Study

    Science.gov (United States)

    Erdman, Laura K.; D’Acremont, Valérie; Hayford, Kyla; Kilowoko, Mary; Kyungu, Esther; Hongoa, Philipina; Alamo, Leonor; Streiner, David L.; Genton, Blaise; Kain, Kevin C.

    2015-01-01

    Background Diagnosing pediatric pneumonia is challenging in low-resource settings. The World Health Organization (WHO) has defined primary end-point radiological pneumonia for use in epidemiological and vaccine studies. However, radiography requires expertise and is often inaccessible. We hypothesized that plasma biomarkers of inflammation and endothelial activation may be useful surrogates for end-point pneumonia, and may provide insight into its biological significance. Methods We studied children with WHO-defined clinical pneumonia (n = 155) within a prospective cohort of 1,005 consecutive febrile children presenting to Tanzanian outpatient clinics. Based on x-ray findings, participants were categorized as primary end-point pneumonia (n = 30), other infiltrates (n = 31), or normal chest x-ray (n = 94). Plasma levels of 7 host response biomarkers at presentation were measured by ELISA. Associations between biomarker levels and radiological findings were assessed by Kruskal-Wallis test and multivariable logistic regression. Biomarker ability to predict radiological findings was evaluated using receiver operating characteristic curve analysis and Classification and Regression Tree analysis. Results Compared to children with normal x-ray, children with end-point pneumonia had significantly higher C-reactive protein, procalcitonin and Chitinase 3-like-1, while those with other infiltrates had elevated procalcitonin and von Willebrand Factor and decreased soluble Tie-2 and endoglin. Clinical variables were not predictive of radiological findings. Classification and Regression Tree analysis generated multi-marker models with improved performance over single markers for discriminating between groups. A model based on C-reactive protein and Chitinase 3-like-1 discriminated between end-point pneumonia and non-end-point pneumonia with 93.3% sensitivity (95% confidence interval 76.5–98.8), 80.8% specificity (72.6–87.1), positive likelihood ratio 4.9 (3.4–7

  12. Molecular analysis of the von hippel-lindau disease gene.

    Science.gov (United States)

    Chernoff, A; Kasparcova, V; Linehan, W M; Stolle, C A

    2001-01-01

    Von Hippel-Lindau (VHL) disease is an autosomal dominant disorder that predisposes the affected individual to develop characteristic tumors. These include CNS hemangioblastoma, retinal angiomas, endolymphatic sac tumors, pancreatic cysts and tumors, epididymal cystadenomas, pheochromocytomas, renal cysts, and clear-cell renal carcinoma. The VHL gene was localized to 3p25 and then isolated by Latif et al. (1). The gene contains three exons with an open reading frame of 852 nucleotides, which encode a predicted protein of 284 amino acids. The VHL protein is believed to have several functions. It is involved in transcription regulation through its inhibition of elongation by binding to the B and C subunits of elongin. Mutations of VHL allow the B and C subunits to bind with the A subunit. This complex then overcomes "pausing" of RNA polymerase during mRNA transcription (2,3). Several studies suggest that the VHL protein is also involved in regulation of hypoxia-inducible transcripts, particularly vascular endothelial growth factor (VEGF), by altering mRNA stability (4,5). Therefore, VHL gene mutations permit the overexpression of VEGF under normoxic conditions, which leads to the angiogenesis believed to be required for tumor growth. The VHL-elongin BC complex (VBC) also binds two other proteins-CUL2 and Rbx1-in a complex that has structural similarity to other E3 ubiquitin ligase complexes (6). Such complexes mediate the degradation of cell-cycle regulatory proteins.

  13. Memory recall in arousing situations - an emotional von Restorff effect?

    Science.gov (United States)

    Wiswede, Daniel; Rüsseler, Jascha; Hasselbach, Simone; Münte, Thomas F

    2006-07-24

    Previous research has demonstrated a relationship between memory recall and P300 amplitude in list learning tasks, but the variables mediating this P300-recall relationship are not well understood. In the present study, subjects were required to recall items from lists consisting of 12 words, which were presented in front of pictures taken from the IAPS collection. One word per list is made distinct either by font color or by a highly arousing background IAPS picture. This isolation procedure was first used by von Restorff. Brain potentials were recorded during list presentation. Recall performance was enhanced for color but not for emotional isolates. Event-related brain potentials (ERP) showed a more positive P300-component for recalled non-isolated words and color-isolated words, compared to the respective non-remembered words, but not for words isolated by arousing background. Our findings indicate that it is crucial to take emotional mediator variables into account, when using the P300 to predict later recall. Highly arousing environments might force the cognitive system to interrupt rehearsal processes in working memory, which might benefit transfer into other, more stable memory systems. The impact of attention-capturing properties of arousing background stimuli is also discussed.

  14. Modernisation of ventilation systems; Modernisierung von Lueftungsanlagen

    Energy Technology Data Exchange (ETDEWEB)

    Richter, W. [Technische Univ. Dresden (Germany). Inst. fuer Thermodynamik und Technische Gebaeudeausruestung

    1997-12-31

    When redeveloping buildings it is common to use window constructions with air-tight rabbets which obviate the inflow of fresh air almost entirely. This leads to the well-known structural-physics and hygienic consequences. As an added effect, the distinctly enhanced thermal insulation results in changes in dynamic heat loss. The paper focuses on the issues of how to safeguard the inflow of fresh air, and the heating capacity of radiators. (MSK) [Deutsch] Da die bei Gebaeudesanierungen eingesetzten fugendichten Fensterkonstruktionen die Nachstroemmoeglichkeiten fuer die Zuluft fast ganz unterbinden, fuehrt das zu den bekannten bauphysikalischen und hygienischen Konsequenzen. Dazu kommen veraenderte dynamische Waermverlustverhaeltnisse aufgrund der deutlich verbesserten Waermedaemmung. Im Folgenden wird schwerpunktmaessig auf die Probleme Zuluftsicherung und Waermeleistung von Heizkoerpern eingegangen.

  15. Ex-ante Evaluation von Investitionsalternativen

    Directory of Open Access Journals (Sweden)

    Matthias Müller

    2017-12-01

    Full Text Available Der Beitrag zeigt, wie mit Hilfe der Methode der agentenbasierten Modellierung und Simulation (ABMS ein Beitrag zur ex-ante Policy-Beratung geleistet werden kann. Anhand eines exemplarischen Anwendungsfalls, der VISIBLE Simulationsumgebung („Virtual Simulation Lab for the Analysis of Investments in Learning and Education“, diskutieren wir die Konsequenzen unterschiedlicher Kooperationsförderinstrumente für Wissensdiffusionsprozesse in Netzwerken am Beispiel der Region Heilbronn-Franken. Die Simulationsergebnisse zeigen, dass die strukturelle Konfiguration eines regionalen Innovationssystems eine zentrale Bedeutung für die Gestaltung von Kooperationsfördermaßnahmen hat und dass Interventionen, die darauf abzielen, Wissenstransfer zwischen den Akteuren anzuregen, genau die entgegengesetzten Wirkungen entfalten können.

  16. Budke, Alexandra; Kanwischer, Detlef; Pott, Andreas (Hg.), Internetgeographien : Beobachtungen zum Verhältnis von Internet, Raum und Gesellschaft / [rezensiert von] Helmut Klüter

    OpenAIRE

    Klüter, Helmut

    2009-01-01

    Rezensiertes Werk: Internetgeographien : Beobachtungen zum Verhältnis von Internet, Raum und Gesellschaft / hrsg. von Alexandra Budke ... - Stuttgart : Steiner, 2004. - 192 S. : Ill., graph. Darst., Kt. - (Erdkundliches Wissen ; 136) ISBN 3-515-08506-8

  17. Ultimate storage in salt caverns / status report; Endverwahrung von Salzkavernen / Stand der Entwicklung

    Energy Technology Data Exchange (ETDEWEB)

    Crotogino, F.; Schmidt, U. [Kavernen Bau- und Betriebs-GmbH, Hannover (Germany)

    1998-12-31

    The contribution reviews the state of knowledge on final storage in salt caverns. The long-term effects of a hermetically sealed, brine-filled cavern are discussed. So far, there are no valid predictions. (orig.) [Deutsch] In dem Beitrag wird der derzeitige Kenntnis- und Diskussionsstand zur Endverwahrung von Salzkavernen zusammengefasst. Aufbauend auf den bisher vorliegenden Vorstellungen zur Soleimpraegnation bei einem Innendruck, der nahezu dem Ueberlagerungsdruck entspricht, werden die denkbaren langfristigen Auswirkungen einer vollstaendig abgeschlossenen solegefuellten Kaverne skizziert; belastbare Prognosen sind derzeit noch nicht moeglich. (orig.)

  18. Entwicklung der Reglementierung von 10 MEM-Berufen im Kontext von Bildungsreformen und dem Wandel in der Arbeitswelt: Eine Kurzstudie im Auftrag von LIBS: Eine Kurzstudie im Auftrag von LIBS Industrielle Berufslehren Schweiz, Baden

    OpenAIRE

    Egg, Maria Esther; Renold, Ursula

    2015-01-01

    Im Auftrag der LIBS Industrielle Berufslehren Schweiz, hat die KOF die Entwicklung von 10 MEM1-Berufsbildern seit dem ersten Berufsbildungsgesetz dargestellt und diese eingebettet in eine kurze Zusammenfassung der wichtigsten Etappenschritte des Schweizer Berufsbildungssystems.

  19. Magnus Georg von Paucker (1787-1855) / Eckhard Spring

    Index Scriptorium Estoniae

    Spring, Eckhard

    2013-01-01

    Eestis sündinud ja Tartu Ülikoolis õppinud silmapaistvast baltisaksa teadlasest ja tema lapselapsest Alexandrine Pauckerist. 23. novembril 2012 Jelgavas/Mitaus toimunud Magnus Georg von Pauckerile pühendatud teaduskonverentsist

  20. Warum das Controlling den systematischen Einsatz von Simulationen vorantreiben sollte

    DEFF Research Database (Denmark)

    Spitzner, Jan; Schneider, Melanie L.

    2017-01-01

    Simulationen werden in der Unternehmenssteuerung heutzutage noch nicht systematisch eingesetzt. Dass sich jedoch die existierenden Hemmnisse durchaus überwinden lassen, legen die Antworten von Studienteilnehmern nahe, die Simulationen häufig einsetzen. Dabei kann Controlling eine Vorreiterrolle e...

  1. Pharmakobotanische Untersuchungen von Lavendelsorten auf dem Plattensee- Plateau

    Directory of Open Access Journals (Sweden)

    Tóth, Frida

    2014-09-01

    Full Text Available Auf dem Hof Dörgicsei Levendula Major GmbH wurden 9 Lavendelsorten (6 Sorten von Lavandula angustifolia und 3 Sorten von Lavandula x intermedia untersucht. Neben den morphologischen und Wachstumseigenschaften wurden auch Frisch- und Trockengewichte bewertet. Quantitative und qualitative Untersuchungen von den Blüten- und Ätherischöldrogen wurden auch durchgeführt. Die statistische Analyse zeigte signifikant höhere Erträge bei den Sorten L. angustifolia ’Essence Purple’ und L. x intermedia ’Edelweiss’. Gehalt und Zusammensetzung von ätherischem Öl war eindeutig bei der Sorte L. angustifolia ’Ellagance Purple’ am günstigsten.

  2. Pure Jauch-Piron states on von Neumann algebras

    International Nuclear Information System (INIS)

    Hamhalter, J.

    1993-01-01

    We study Jauch-Piron states and two-valued measures on von Neumann algebra. We prove as the main result that, under some set-theoretical assumption, a pure state of a von Neumann algebra A not containing a central abelian portion is Jauch-Piron if and only if it is σ-additive. Moreover, we show that this result holds for type I factor indenpendently on the set-theoretical axiomatics. As a consequence we obtain a lucid characterization of pure Jauch-Piron states on von Neumann algebras acting on a Hilbert space with real-nonmeasurable dimension (this can be viewed as a generalization of the paper). We also characterize the von Neumann algebras whose logic of projections is Jauch-Piron. Finally, we prove that every two-valued measure on the projection logic of A, where A contains no type I 2 central portion, has to be concentrated at an abelian direct summand of A. (orig.)

  3. Von Krahli Teater toob Eestisse erakordse auhinna / Tiit Tuumalu

    Index Scriptorium Estoniae

    Tuumalu, Tiit, 1971-

    2004-01-01

    Bessie-auhinna puhul, millega New Yorgis pärjati Von Krahli Teatri lavastust "Luikede järv." Mõjukuselt on seda võrreldud Broadway teatriauhinna Tonyga. Lisatud lühiandmed P. Jalaka ja S. Pepeljajevi kohta

  4. Frobenius theory for positive maps of von Neumann algebras

    International Nuclear Information System (INIS)

    Albeverio, S.; Hoegh-Krohn, R.

    1978-01-01

    Frobenius theory about the cyclic structure of eigenvalues of irreducible non negative matrices is extended to the case of positive linear maps of von Neumann algebras. Semigroups of such maps and ergodic properties are also considered. (orig.) [de

  5. Optimized sampling of hydroperoxides and investigations of the water vapour dependence of hydroperoxide formation during ozonolysis of alkenes; Optimierung der Probenahme von Hydroperoxiden und Untersuchungen zur Wasserdampfabhaengigkeit der Bildung von Hydroperoxiden bei der Ozonolyse von Alkenen

    Energy Technology Data Exchange (ETDEWEB)

    Becker, K.H.; Plagens, H.

    1997-06-01

    There are several sampling methods for hydroperoxides none of which is particularly reliable. The authors therefore tested three new methods in order to optimize hydroperoxide sampling and, using the optimized sampling procedure, to investigate the water vapour dependence of hydroperoxide formation during ozonolysis of alkenes. (orig.) [Deutsch] Fuer die Probenahme von Hydroperoxiden existieren verschiedene Verfahren, von denen bisher keines als besonders zuverlaessig angesehen werden konnte. Daher wurden in dieser Arbeit drei Verfahren getestet, um die Probenahme von Hydroperoxiden zu optimieren und mit dem entsprechenden Verfahren die Wasserdampfabhaengigkeit der Bildung von Hydroperoxiden bei der Ozonolyse von Alkenen zu untersuchen. (orig.)

  6. Numerical Analysis Of Buckling Of Von Mises Planar Truss

    Directory of Open Access Journals (Sweden)

    Kalina Martin

    2015-12-01

    Full Text Available A computational algorithm of a discrete model of von Mises planar steel truss is presented. The structure deformation is evaluated by seeking the minimal potential energy. The critical force invented by mathematical solution was compared with solution by computer algorithm. Symmetric and asymmetric effects of initial shape of geometric imperfection of axis of struts are used in model. The shapes of buckling of von Mises planar truss of selected vertical displacement of top joint are shown.

  7. Analytische und Effektor-Studien von N-Acyl-Ethanolaminphosphaten

    OpenAIRE

    Ates, Ebru

    2011-01-01

    Bei N-Acyl-Ethanolaminphosphaten handelt es sich um eine bislang wenig untersuchte Klasse polarer Substanzen, deren Erforschung aufgrund ihrer strukturellen Analogie zu apolaren, physiologisch wirksamen N-Acyl-Ethanolaminen von Interesse ist. Zu bear-beiten waren analytische Fragestellungen, die auch synthetische Aufgaben beinhalteten, wie Methodenentwicklung und Versuche zur Erfassung von N-Acyl-Ethanolamin-phosphaten in ausgewählten Lebensmitteln sowie strukturelle Studien zur „Bioaktivität...

  8. Spurenstoffuntersuchungen zur Bildung und Ausbreitung von Wassermassen im subpolaren Nordatlantik

    OpenAIRE

    Hildebrandt, Hauke

    2001-01-01

    In der vorliegenden Arbeit wurde ein umfangreicher Spurenstoffdatensatz aus dem subpolaren Nordatlantik erstellt und ausgewertet, der Tritium-, Helium- und Neon- sowie O-18-Messungen umfaßt. Das Hauptaugenmerk galt dabei der Bildung und Ausbreitung der tiefen Wassermassen und deren Variabilität auf Zeitskalen von einigen Jahren. Anhand von Tracermittelwerten, die mit Hilfe eines optimierten Interpolationsverfahrens gewonnen wurden, konnte gezeigt werden, daß die konvektive Neubildung de...

  9. Nash y von Neumann: mundos posibles y juegos de lenguaje

    Directory of Open Access Journals (Sweden)

    Salazar , Boris

    2004-06-01

    Full Text Available Este ensayo emplea las nociones de juego de lenguaje y de equivalencia entre juegos para examinar la decisión de John Nash de no jugar el juego coalicional que propuso John von Neumann. El argumento central es que Nash concibió una clase de mundos posibles incompatible con la de von Neumann, y que en el origen de esa divergencia estarían sus distintas nociones de racionalidad.

  10. Von Neumann's impossibility proof: Mathematics in the service of rhetorics

    Science.gov (United States)

    Dieks, Dennis

    2017-11-01

    According to what has become a standard history of quantum mechanics, in 1932 von Neumann persuaded the physics community that hidden variables are impossible as a matter of principle, after which leading proponents of the Copenhagen interpretation put the situation to good use by arguing that the completeness of quantum mechanics was undeniable. This state of affairs lasted, so the story continues, until Bell in 1966 exposed von Neumann's proof as obviously wrong. The realization that von Neumann's proof was fallacious then rehabilitated hidden variables and made serious foundational research possible again. It is often added in recent accounts that von Neumann's error had been spotted almost immediately by Grete Hermann, but that her discovery was of no effect due to the dominant Copenhagen Zeitgeist. We shall attempt to tell a story that is more historically accurate and less ideologically charged. Most importantly, von Neumann never claimed to have shown the impossibility of hidden variables tout court, but argued that hidden-variable theories must possess a structure that deviates fundamentally from that of quantum mechanics. Both Hermann and Bell appear to have missed this point; moreover, both raised unjustified technical objections to the proof. Von Neumann's argument was basically that hidden-variables schemes must violate the ;quantum principle; that physical quantities are to be represented by operators in a Hilbert space. As a consequence, hidden-variables schemes, though possible in principle, necessarily exhibit a certain kind of contextuality. As we shall illustrate, early reactions to Bohm's theory are in agreement with this account. Leading physicists pointed out that Bohm's theory has the strange feature that pre-existing particle properties do not generally reveal themselves in measurements, in accordance with von Neumann's result. They did not conclude that the ;impossible was done; and that von Neumann had been shown wrong.

  11. Räumliche Aspekte von Transformationsproblemen aus systemtheoretischer Perspektive

    OpenAIRE

    Klüter, Helmut

    2000-01-01

    Der mit dem Topos "Transformation von Wirtschafts- und Gesellschaftssystemen" axiomatisch angenommene Unvereinbarkeit sozialistischer und marktwirtschaftlicher Strukturen ist aus raumwissenschaftlicher Sicht nicht nachvollziehbar. Zum einen gibt es in Wirtschaftsgeographie und Infrastrukturtheorie eine ganze Reihe von Gemeinsamkeiten und Berührungspunkten, die man für den konstruktiven Systemumbau nutzen kann. Zum andern benötigt der Umbau selbst eine räumliche Infrastruktur. Und zum dritten ...

  12. Integration von 3D-Kamerasystemen am Gabelstapler

    OpenAIRE

    Kleinert, Steffen; Overmeyer, Ludger

    2013-01-01

    Dieser Beitrag beschreibt die Integration von laufzeitmessenden 3D Kamerasystemen in die Gabelzinkenspitzen eines Flurförderzeugs. Mit Hilfe der integrierten Kameras und deren ausgewerteter Aufnahmen wurde ein Assistenzsystem für die Handhabung von Ladungsträgern realisiert, das dem Fahrer des Flurförderzeugs Verfahrempfehlungen für die Optimierung der Relativposition zwischen Gabelzinken und Ladungsträger bzw. Lagerplatz ausgibt. Neben der Vorstellung der verwendeten Kamera-Hardware und der ...

  13. Die Darstellung von guten und schlechten Beziehungen in Kinderzeichnungen

    OpenAIRE

    Gramel, Sabine

    2005-01-01

    Nach welchen Kriterien sich Bilder, auf denen Kinder eine positive Beziehung darstellen, von Bildern unterscheiden, auf denen negative Beziehungen dargestellt sind, wurde an einer Stichprobe von 45 Kindern zwischen 4;6 und 11;6 Jahren untersucht. Die Kinder fertigten jeweils ein positives und ein negatives Beziehungsbild an. Es zeigte sich, dass die Kinder in beiden Beziehungskategorien zum großen Teil Gleichaltrige darstellten. Sie benannten für ihre Bilder Kriterien, anhand derer man die po...

  14. Zur Dialektik von Soft Skills und fachlicher Kompetenz

    OpenAIRE

    Jendrowiak, Hans-Werner

    2010-01-01

    [Der Autor stellt folgende Thesen zur Dialektik von Soft Skills und fachlicher Bildung auf:] 1. Soft Skills sind normale Bildungskategorien und Teil einer Allgemeinen Bildung. […] 2. Soft Skills sind als personalgebundene Kriterien auch immer schon Gegenstand bildungstheoretischer Debatten. […] 3. Soft Skills ist eine trendorientierte Bezeichnung für Bildung. […] 4. Soft Skills sind Ausdruck von Vorstellungen, Ideen und Theorien (Schulkultur, Unternehmenskultur, Unternehmensphilosophie). 5. S...

  15. Politische Bildung im Kontext von Regierung, Unterricht und Zucht

    Directory of Open Access Journals (Sweden)

    Thomas Rucker

    2014-02-01

    Full Text Available Johann Friedrich Herbart (1776-1841 gilt als der Begründer der wissenschaftlichen Pädagogik. In diesem Beitrag wird zu zeigen versucht, dass Herbart die Unterstützung politischer Bildung als eine Aufgabe von Regierung, Unterricht und Zucht bestimmt und in seinem Werk wichtige „Bausteine“ für eine Theorie der politischen Bildung unter den Bedingungen von Erziehung vorlegt hat. Nach Herbart ist das politische Selbst- und Weltverhältnis auf Sachverhalte bezogen, die nicht nur die Lebensführung einzelner Menschen, sondern die Lebensführung einer Mehrzahl von Menschen betreffen. Nicht das Zusammenleben von Menschen generell ist jedoch Orientierungsgesichtspunkt des politischen Selbst- und Weltverhältnisses, sondern nur das problematisch gewordene Zusammenleben. Politik ergibt sich nach Herbart aus einem Konflikt hinsichtlich der Frage, wie das Zusammenleben von Menschen geregelt sein sollte. Während die Regierung lediglich mittelbar einen Beitrag zur politischen Bildung leistet, indem sie die Voraussetzungen für Unterricht und Zucht bereitstellt, fungieren die beiden zuletzt genannten Formen von Erziehung als die eigentlichen Medien, in denen die politische Bildung im Sinne Herbarts ihren Ort hat.

  16. Entwicklung von Extraktions- und Absorptionssystemen auf Basis ionischer Flüssigkeiten für die Entschwefelung von Kohlenwasserstoffen

    OpenAIRE

    Kuhlmann, Esther

    2008-01-01

    Da die Anforderungen an den Schwefelgehalt der fossilen Brennstoffe - nicht zuletzt durch gesetzliche Richtlinien bezüglich der Schadstoffemissionen - im Laufe der Zeit ständig gestiegen sind, sind effektive Entschwefelungsverfahren für fossile Brennstoffe von hohem Interesse. Die derzeitige Entschwefelungstechnologie basiert auf dem HDS-Verfahren, alternative Verfahren sind aber wünschenswert, insbesondere wenn Anwendungen einen Schwefelgehalt von weit unter 10 ppm erforderlich machen. Daher...

  17. Small specimen test results and application of advanced models for fracture mechanics assessment of RPV integrity; Ergebnisse von Kleinproben und Anwendung von Modellansaetzen zur bruchmechanischen Bewertung der RDB-Integritaet

    Energy Technology Data Exchange (ETDEWEB)

    Keim, Elisabeth; Huemmer, Matthias [AREVA NP GmbH (Germany); Hoffmann, Harald [VGB (Germany); Nagel, Gerhard [e-on Kernkraft (Germany); Kuester, Karin [VENE (Germany); Koenig, Guenter; Ilg, Ulf [EnBW (Germany); Widera, Martin [RWE (Germany); Rebsamen, Daniel [KKW Goesgen (Germany)

    2008-07-01

    For the RPV (reactor pressure vessel) integrity assessment the transferability of specimen test results to components is of main importance. The international project TIMES (transferability of fracture toughness of irradiated materials to components and structures) is focussed on the transferability of fracture mechanical characteristics of irradiated materials to components or structures, in order to allow the quantification of differences between sample and component characteristics based on experiments and calculations. The studies were performed for the brittle and brittle-ductile regions of the material characteristics using specimens from original RPV materials in different conditions. Based on case studies the consequence of a component assessment with postulated defects are shown when specimen-related materials properties are used. Since it is not possible to prove the transferability for an RPV in detail, component-similar effects were investigated that allow in combination with numerical modelling to quantify the safety margin. Samples and experimental procedures were developed that simulated the real component situation. The effects of crack depth and multiaxial loads, relevant for real components, were investigated with these samples. A micromechanical model was developed based on the weakest link theory and the statistical failure probability; this model is used for the prediction of fracture toughness of samples and components with defects. For a component with postulated defects the safety margin was assessed using different methodologies, based on standard fracture mechanical samples, taking into account component specific aspects. [German] Fuer die Bewertung der RDB-Integritaet ist die Uebertragbarkeit von Probenkennwerten auf Bauteile von grosser Bedeutung. Dazu wurde das Projekt ''TIMES'' - ein internationales Projekt zur Uebertragbarkeit von Bruchzaehigkeitskennwerten von bestrahlten Materialien auf Komponenten und Strukturen - durchgefuehrt, um

  18. Electronic Resource Management System. Vernetzung von Lizenzinformationen

    Directory of Open Access Journals (Sweden)

    Michaela Selbach

    2014-12-01

    Full Text Available In den letzten zehn Jahren spielen elektronische Ressourcen im Bereich der Erwerbung eine zunehmend wichtige Rolle: Eindeutig lässt sich hier ein Wandel in den Bibliotheken (fort vom reinen Printbestand zu immer größeren E-Only-Beständen feststellen. Die stetig wachsende Menge an E-Ressourcen und deren Heterogenität stellt Bibliotheken vor die Herausforderung, die E-Ressourcen effizient zu verwalten. Nicht nur Bibliotheken, sondern auch verhandlungsführende Institutionen von Konsortial- und Allianzlizenzen benötigen ein geeignetes Instrument zur Verwaltung von Lizenzinformationen, welches den komplexen Anforderungen moderner E-Ressourcen gerecht wird. Die Deutsche Forschungsgemeinschaft (DFG unterstützt ein Projekt des Hochschulbibliothekszentrums des Landes Nordrhein-Westfalen (hbz, der Universitätsbibliothek Freiburg, der Verbundzentrale des Gemeinsamen Bibliotheksverbundes (GBV und der Universitätsbibliothek Frankfurt, in dem ein bundesweit verfügbares Electronic Ressource Managementsystem (ERMS aufgebaut werden soll. Ein solches ERMS soll auf Basis einer zentralen Knowledge Base eine einheitliche Nutzung von Daten zur Lizenzverwaltung elektronischer Ressourcen auf lokaler, regionaler und nationaler Ebene ermöglichen. Statistische Auswertungen, Rechteverwaltung für alle angeschlossenen Bibliotheken, kooperative Datenpflege sowie ein über standardisierte Schnittstellen geführter Datenaustausch stehen bei der Erarbeitung der Anforderungen ebenso im Fokus wie die Entwicklung eines Daten- und Funktionsmodells. In the last few years the importance of electronic resources in library acquisitions has increased significantly. There has been a shift from mere print holdings to both e- and print combinations and even e-only subscriptions. This shift poses a double challenge for libraries: On the one hand they have to provide their e-resource collections to library users in an appealing way, on the other hand they have to manage these

  19. Von Roll RCP method - first experiences; Von Roll RCP - Verfahren. Erste Erfahrungen

    Energy Technology Data Exchange (ETDEWEB)

    Capitaine, P.; Engweiler, J. [Roll Umwelttechnik AG, Zuerich (Switzerland)

    1998-09-01

    The RCP method was designed as a residue-optimised alternative to the thermally optimised grate firing of residual wastes. Its technical realisation and development to market maturity took no more than 5 years. In the first process stage the waste is converted to high-carbon pyrolysis charcoal and high-rank gas in the absence of oxygen. In the second stage these substances are oxidised by addition of oxygen. The resulting temperature causes the non-combustible constituents of the slag to melt. In a third, optional, stage this molten slag can be liberated of (heavy) metals to such an extent that it can subsequently be used directly as additive for grinding. Further exhaust gas treatment is facilitated by the use of a circulatory fluidised-bed secondary combustion chamber. Despite the reduced flue gas volume and resultant higher pollutant concentrations in the crude gas, overall emissions are lower than in conventional plants. [Deutsch] Das reststoffoptimierte RCP Verfahren ist als Alternative zur thermisch optimierten Rostverbrennung von Restabfaellen konzipiert. In nur fuenf Jahren wurde das Verfahren technisch umgesetzt und zur Marktreife entwickelt. In einer ersten Stufe des Verfahrens wird der Abfall unter Luftabschluss in einen kohlenstoffreichen Pyrolysekoks und eine heizwertreiches Gas umgesetzt. Im zweiten Schritt werden diese Stoffe unter Zugabe von Sauerstoff oxidiert. Dabei treten Temperaturen auf, bei denen die nichtbrennbaren Bestandteile der Schlacke schmelzen. Optional wird diese Schmelzschlacke in einem dritten Schritt derart von (Schwer-) Metallen befreit, dass sie anschliessend direkt als Zement-Zumahlstoff eingesetzt werden kann. Die Nutzung der zirkulierenden Wirbelschicht - Nachbrennkammer zur Abgasbehandlung vereinfacht die weitergehende Abgasbehandlung. Trotz verringertem Rauchgasvolumen und damit hoeheren Schadstoffkonzentrationen im Rohgas werden die Gesamtemissionen gegenueber konventionellen Anlagen verringert. (orig./SR)

  20. Einfluss von Informationskompetenz-Veranstaltungen auf die Qualität von Masterarbeiten

    Directory of Open Access Journals (Sweden)

    Gary Seitz

    2016-02-01

    Full Text Available Am Geographischen Institut der Universität Zürich haben die Studierenden, welche als erster Jahrgang die IK-Veranstaltung als Pflichtmodul absolvierten, ihre Masterarbeit abgeschlossen. Mit einer quantitativen Auswertung wird untersucht, ob sich die Qualität der Quellen in den Masterarbeiten verbessert hat. Dazu werden die Literaturverzeichnisse einer bibliometrischen Analyse unterzogen. Anschliessend werden die erhaltenen Werte mit denjenigen verglichen, welche von Arbeiten ohne IK-Schulung erhoben wurden. Diese Methodik könnte ein Werkzeug darstellen, um Informationskompetenz-Veranstaltungen bezüglich ihrer Relevanz für wissenschaftliches Arbeiten evaluieren zu können.

  1. "Die Toten reiten schnelle." Literarische Zitate in Briefen von und an Alexander von Humboldt

    Directory of Open Access Journals (Sweden)

    Ingo Schwarz

    2007-04-01

    Full Text Available Article in GermanAbstract in English and GermanAlexander von Humboldt and his correspondents liked to enrich or embellish their letters with quotations from classic works of ancient literature as well as from recent poems, plays, or novels. This paper tries to show that references to literature were very often used in order to express thoughts and feelings more clearly not so much for impressing the recipients of letters with high education. In educated circles a good knowledge of ancient and modern works of literature was a standard requirement, which often allowed the letter writers to use quotations in a playful manner.

  2. Microbial anaerobic methane cycling in the subseafloor at the Von Damm hydrothermal vent field, Mid-Cayman Rise

    Science.gov (United States)

    Huber, J. A.; Reveillaud, J. C.; Stepanauskas, R.; McDermott, J. M.; Sylva, S. P.; Seewald, J.

    2013-12-01

    The Mid-Cayman Rise (MCR) is Earth's deepest and slowest spreading mid-ocean ridge located in the western Caribbean. With an axial rift valley floor at a depth of ~4200-6500 m, it represents one of the deepest sections of ridge crest worldwide. In 2009, the world's deepest hydrothermal vents (Piccard at 4960 m) and an ultramafic-influenced system only 20 km away on top of an oceanic core complex (Von Damm at 2350 m) were discovered along the MCR. Each site is hosted in a distinct geologic setting with different thermal and chemical regimes. The Von Damm site is a particularly interesting location to examine chemolithoautotrophic subseafloor microbial communities due to the abundant hydrogen, methane, and organic compounds in the venting fluids. Here, we used a combination of stable isotope tracing, next-generation sequencing, and single cell techniques to determine the identity, activity, and genomic repertoire of subseafloor anaerobic archaea involved in methane cycling in hydrothermal fluids venting at the Von Damm site. Molecular sequencing of phylogenetic marker genes revealed the presence of diverse archaea that both generate and consume methane across a geochemical and thermal spectrum of vents. Stable isotope tracing experiments were used to detect biological utilization of formate and dissolved inorganic carbon, and methane generation at 70 °C under anaerobic conditions. Results indicate that methanogenesis with formate as a substrate is occurring at 70 °C at two Von Damm sites, Ginger Castle and the Main Orifice. The results are consistent with thermodynamic predictions for carbon speciation at the temperatures encountered at the ultramafic-hosted Von Damm, where formate is predicted to be thermodynamically stable, and may thus serve as a an important source of carbon. Diverse thermophilic methanogenic archaea belonging to the genera Methanothermococcus were detected at all vent sites with both 16S rRNA tag sequencing and single cell sorting. Other

  3. Richard von Volkmann: surgeon and Renaissance man.

    Science.gov (United States)

    Willy, Christian; Schneider, Peter; Engelhardt, Michael; Hargens, Alan R; Mubarak, Scott J

    2008-02-01

    Richard von Volkmann (1830-1889), one of the most important surgeons of the 19(th) century, is regarded as one of the fathers of orthopaedic surgery. He was a contemporary of Langenbeck, Esmarch, Lister, Billroth, Kocher, and Trendelenburg. He was head of the Department of Surgery at the University of Halle, Germany (1867-1889). His popularity attracted doctors and patients from all over the world. He was the lead physician for the German military during two wars. From this experience, he compared the mortality of civilian and war injuries and investigated the general poor hygienic conditions in civilian hospitals. This led him to introduce the "antiseptic technique" to Germany that was developed by Lister. His powers of observation and creativity led him to findings and achievements that to this day bear his name: Volkmann's contracture and the Hueter-Volkmann law. Additionally, he was a gifted writer; he published not only scientific literature but also books of children's fairy tales and poems under the pen name of Richard Leander, assuring him a permanent place in the world of literature as well as orthopaedics.

  4. Geschichte der Natur bei Alexander von Humboldt

    Directory of Open Access Journals (Sweden)

    Christian Helmreich

    2009-05-01

    Full Text Available Article in German, Abstracts in English, German and French.This article analyses the importance of an historical view of nature in the works of Alexander von Humboldt. In several of his first writings, Humboldt seems to outline the importance of what one may call history of nature. But even before his famous American travel, his position changed and he became reluctant to accept the seriousness of historical enquiry in the area of natural sciences: if we want to reconstruct the past state of nature, we cannot rely on empirical proofs; and history of nature is therefore necessarily based on uncertain hypotheses. Humboldt kept his sceptical attitude in the first decades of the 19th century, despite the positive results of the palaeontological researches of his scientific colleagues. However, he gradually convinced himself of the scientific interest of historical investigations in the natural sciences. The Cosmos paradoxally displays two apparently conflicting points of view: in his methodological remarks, Humboldt maintains that precise accounts of the past state of nature are out of reach of human knowledge, yet elsewhere in the same Cosmos he gives broad and rather vivid descriptions of the eventful history of nature.

  5. Hypercontractivity in group Von Neumann algebras

    CERN Document Server

    Junge, Marius; Parcet, Javier

    2017-01-01

    In this paper, the authors provide a combinatorial/numerical method to establish new hypercontractivity estimates in group von Neumann algebras. They illustrate their method with free groups, triangular groups and finite cyclic groups, for which they obtain optimal time hypercontractive L_2 \\to L_q inequalities with respect to the Markov process given by the word length and with q an even integer. Interpolation and differentiation also yield general L_p \\to L_q hypercontrativity for 1 < p \\le q < \\infty via logarithmic Sobolev inequalities. The authors' method admits further applications to other discrete groups without small loops as far as the numerical part-which varies from one group to another-is implemented and tested on a computer. The authors also develop another combinatorial method which does not rely on computational estimates and provides (non-optimal) L_p \\to L_q hypercontractive inequalities for a larger class of groups/lengths, including any finitely generated group equipped with a condit...

  6. Ecobalance of natural gas vehicles; Oekobilanz von Erdgasfahrzeugen

    Energy Technology Data Exchange (ETDEWEB)

    Nigge, K.M. [Simon, Kucher und Partners Strategy und Marketing Consultants GmbH, Bonn (Germany)

    2000-07-01

    The impacts on human health and the natural environment of using natural gas, Diesel and petrol as fuels for city buses and passenger cars are compared in a Life Cycle Assessment. In addition to the burning of the fuels in the engines, this assessment also comprises the upstream processes of the fuel supply chain. Despite the increased energy demand of the vehicles, natural gas is associated with the lowest impacts overall for both city buses and passenger cars. The health impacts that can be avoided through the use of natural gas instead of Diesel or petrol thereby differ only weakly between the use of the vehicles in cities of various sizes within Germany. From the perspective of environmental protection, the market introduction of natural gas vehicles therefore does not need remain limited to large cities within agglomerated regions. (orig.) [German] Die Auswirkungen der Verwendung von Erdgas, Diesel und Benzin als Kraftstoffe fuer Stadtbusse und Pkw auf die menschliche Gesundheit und die natuerliche Umwelt werden in einer Oekobilanz verglichen. Diese umfasst neben der motorischen Verbrennung der Kraftstoffe auch die vorgelagerten Prozessketten der Kraftstoffbereitstellung. Sowohl fuer Stadtbusse als auch fuer Pkw schneidet Erdgas trotz eines energetischen Mehrbedarfes der Fahrzeuge insgesamt am guenstigsten ab. Die durch den Einsatz von Erdgas anstelle von Diesel oder Benzin vermeidbaren Gesundheitsschaeden unterscheiden sich dabei zwischen einem Einsatz der Fahrzeuge in Staedten verschiedener Groesse innerhalb von Deutschland nur wenig. Die Markteinfuehrung von Erdgasfahrzeugen muss also aus Sicht des Umweltschutzes nicht auf grosse Staedte in Ballungsgebieten beschraenkt bleiben. (orig.)

  7. Decreased plasma ADAMTS-13 activity as a predictor of postoperative bleeding in cyanotic congenital heart disease

    Directory of Open Access Journals (Sweden)

    Rosangela P.S. Soares

    2013-04-01

    Full Text Available OBJECTIVE: To analyze the preoperative plasma antigenic concentration and activity of von Willebrand factor and its main cleaving protease ADAMTS-13 in pediatric patients with cyanotic congenital heart disease undergoing surgical treatment and investigate possible correlations with postoperative bleeding. METHODS: Plasma antigenic concentrations (von Willebrand factor:Ag and ADAMTS-13:Ag were measured using enzyme-linked immunoassays. Collagen-binding assays were developed to measure biological activities (von Willebrand factor:collagen binding and ADAMTS-13 activity. The multimeric structure of von Willebrand factor was analyzed using Western immunoblotting. Demographic, diagnostic, and general and specific laboratory data and surgery-related variables were subjected to univariate, bivariate, and multivariate analysis for the prediction of postoperative bleeding. RESULTS: Forty-eight patients were enrolled, with ages ranging from 9 months to 7.6 years (median 2.5 years. The plasma concentrations of von Willebrand factor:Ag and ADAMTS-13:Ag were decreased by 65 and 82%, respectively, in the patients compared with the controls (p<0.001. An increased density of low-molecular-weight fractions of von Willebrand factor, which are suggestive of proteolytic degradation (p = 0.0081, was associated with decreased ADAMTS-13 activity, which was likely due to ADAMTS-13 consumption (71% of controls, p = 0.0029 and decreased von Willebrand factor:collagen binding (76% of controls, p = 0.0004. Significant postoperative bleeding occurred in 13 patients. The preoperative ADAMTS-13 activity of <64.6% (mean level for the group, preoperative activated partial thromboplastin time, and the need for cardiopulmonary bypass were characterized as independent risk factors for postoperative bleeding, with respective hazard ratios of 22.35 (95% CI 1.69 to 294.79, 1.096 (95% CI 1.016 to 1.183, and 37.43 (95% CI 1.79 to 782.73. CONCLUSION: Low plasma ADAMTS-13

  8. Proof of pipeline strength based on measurements of inspection pigs; Festigkeitsnachweis von Pipelines aufgrund der Messergebnisse von Pruefmolchen

    Energy Technology Data Exchange (ETDEWEB)

    De la Camp, H.J.; Feser, G.; Hofmann, A.; Wolf, B.; Schmidt, H. [TUeV Sueddeutschland Bau und Betrieb GmbH, Muenchen (Germany); Herforth, H.E.; Juengling, K.H.; Schmidt, W. [TUeV Anlagentechnik GmbH, Berlin-Schoeneberg (Germany). Unternehmensgruppe TUeV Rheinland/Berlin-Brandenburg

    2002-01-01

    The report is aimed at collecting and documenting the state of the art and the extensive know how of experts and pipeline operators with regard to judging the structural integrity of pipelines. In order to assess the actual mechanical strength of pipelines based on measurement results obtained by inspection pigs, guidance is given for future processing, which eventually can be used as a basis for an industry standard. A literature study of the commercially available types of inspection pigs describes and synoptically lists the respective pros and cons. In essence the report comprises besides check lists of operating data for the pipeline and the pig runs mainly the evaluation of defects and respective calculating procedures. Included are recommendations regarding maintenance planning, verification of defects as well as repetition of pig runs. (orig.) [German] Ziel des Berichtes ist die Erfassung und Dokumentation zum derzeitigen Stand der Technik und des vorhandenen umfangreichen Know-how von Sachverstaendigen und Pipelinebetreibern auf dem Gebiet der sicherheitstechnischen Beurteilung von Pipelines. Fuer den Festigkeitsnachweis von Pipelines aufgrund der Messergebnisse von Pruefmolchen wurde ein Leitfaden als Basis fuer die zukuenftige Vorgehensweise erstellt, der eventuell die Grundlage eines normativen Regelwerkes bilden kann. In einer Literaturstudie wurden die auf dem Markt befindlichen Pruefmolchtypen zusammenfassend beschrieben und ihre Vor- und Nachteile tabellarisch gegenuebergestellt und bewertet. Neben der Erstellung von Checklisten fuer notwendige Daten zum Betrieb der Pipeline und der Molchlaeufe bildet die Fehlerbewertung mit entsprechenden Berechnungsverfahren den Hauptteil dieses Berichtes. Hinweise zur Instandhaltungsplanung (Fehlerverifikation und Molchlaufwiederholung) werden gegeben. (orig.)

  9. Ein „neuer" javanischer Fundort von Phrynoglossus laevis laevis ( Gthr.)

    NARCIS (Netherlands)

    Brongersma, L.D.

    1935-01-01

    In der herpetologischen Sammlung, die dem Rijksmuseum van Natuurlijke Historie, Leiden, vor etwa hundert Jahre von Boie und Macklot übersandt wurde, befanden sich zwei Exemplare von Phrynoglossus laevis laevis (Gthr.). Diese Stücke wurden von Van Kampen (1923, p. 232 Fussnote: Oxyglossus laevis) in

  10. Neuro- und Gliotoxizität von Wolframcarbid-basierten Nanopartikeln in vitro

    OpenAIRE

    Bastian, Susanne

    2011-01-01

    Die Anzahl neurodegenerativer Erkrankungen nimmt in unserer Gesellschaft stetig zu. Obwohl inzwischen eine Reihe genetischer Ursachen identifiziert worden sind, wird auch der Einfluss von Umweltfaktoren bei der Pathogenese dieser Erkrankungen zunehmend in Betracht gezogen. Der Beitrag von ultrafeinen Partikeln aus Industrie und Umwelt auf neurodegenerative Erkrankungen steht daher zunehmend im Fokus der Forschung. Die Translokation von ultrafeinen Partikeln bzw. Nanopartikeln ins Gehirn ist b...

  11. Muuga / Mary von Grünewaldt ; tõlk. Mati Sirkel

    Index Scriptorium Estoniae

    Grünewaldt, Mary von

    2004-01-01

    Leo Zoegelt ostetud Muuga mõisahoone korrastamisest ja uue hoone ehitamisest C. T. von Neffi kunstikogu paigutamise tarbeks. Tütre mälestused. Tõlgitud raamatust: Skizzen und Bilder aus dem Leben Carl Timoleon von Neff / Mary von Grünewaldt. Darmstadt, 1887

  12. Die grossen Physiker und ihre Entdeckungen von den fallenden Körpern zu den Quarks

    CERN Document Server

    Segrè, Emilio

    1998-01-01

    Von Galileo Galilei bis zu Richard Feynman und Murray Gell-Mann - von den fallenden Körpern zu den Quarks: Der Physiknobelpreisträger Emilio Segre hat seine ganz persönliche Geschichte der Physik geschrieben. Er erzählt von den großen Gestalten und deren wichtigen Entdeckungen mit großer Anschaulichkeit und Lebendigkeit.

  13. Vergleich verschiedener Methoden zur Haftkraftmessung von Dentinadhäsiven

    OpenAIRE

    Schwertner, Katharina

    2010-01-01

    Zur Bestimmung der Haftkraft von Adhäsiven stehen verschiedene Methoden zur Verfügung. Ziel dieser Studie war es, vier gebräuchliche in vitro Haftkraftmessmethoden (Tensile Bond Strength Test, Shear Bond Strength Test, Microtensile Bond Strength Test, Push-out Bond Strength Test) an drei unterschiedlichen Adhäsivsystemen (Syntac, Clearfil SE Bond, Adper Scotchbond Multi Purpose) zu testen und die Ergebnisse zu vergleichen. Die Haftkräfte sind abhängig von der verwendeten Messmethode. Viele Pa...

  14. The smooth entropy formalism for von Neumann algebras

    International Nuclear Information System (INIS)

    Berta, Mario; Furrer, Fabian; Scholz, Volkher B.

    2016-01-01

    We discuss information-theoretic concepts on infinite-dimensional quantum systems. In particular, we lift the smooth entropy formalism as introduced by Renner and collaborators for finite-dimensional systems to von Neumann algebras. For the smooth conditional min- and max-entropy, we recover similar characterizing properties and information-theoretic operational interpretations as in the finite-dimensional case. We generalize the entropic uncertainty relation with quantum side information of Tomamichel and Renner and discuss applications to quantum cryptography. In particular, we prove the possibility to perform privacy amplification and classical data compression with quantum side information modeled by a von Neumann algebra

  15. Dr. Space the life of Wernher von Braun

    CERN Document Server

    Ward, Bob

    2013-01-01

    Written by veteran aerospace journalist Bob Ward, who spent years investigating his subject, this biography presents a revealing but even-handed portrait of the father of modern rocketry. As he chronicles Wernher von Braun's life, Ward explodes many myths and misconceptions about the controversial genius who was a hero to some, a villain to others. The picture of von Braun that emerges is of a brilliant scientist with limitless curiosity and a drive to achieve his goals at almost any price from, developing the world's first ballistic missile used against the Allies in World War II to help

  16. Die Bundesstatistik als Anbieter und Nutzer von raumbezogenen Daten

    Directory of Open Access Journals (Sweden)

    R. Humbel

    Einige konkrete und potentielle Anwendungen der vorhandenen Daten sollen das Potential und die Breite der Fragestellungen, die damit angegangen werden können, illustrieren. Eine besondere Stellung dürfte in Zukunft aber auch die Satellitenfernerkundung erhalten, deren Daten und Auswertungen eine willkommene Ergänzung für die eher traditionellen GIS-Datensätze bilden werden. Ein erster Pilotversuch wurde vor wenigen Monaten im BFS gestartet, der zum Ziel hat, die Machbarkeit einer gesamtschweizerischen Unterscheidung von Laub-, Nadel- und Mischwald als Ergänzung der auf der Grundlage von konventionellen Luftbildern erhobenen Arealstatistik nachzuweisen.

  17. The smooth entropy formalism for von Neumann algebras

    Energy Technology Data Exchange (ETDEWEB)

    Berta, Mario, E-mail: berta@caltech.edu [Institute for Quantum Information and Matter, California Institute of Technology, Pasadena, California 91125 (United States); Furrer, Fabian, E-mail: furrer@eve.phys.s.u-tokyo.ac.jp [Department of Physics, Graduate School of Science, University of Tokyo, Tokyo, Japan and Institute for Theoretical Physics, Leibniz University Hanover, Hanover (Germany); Scholz, Volkher B., E-mail: scholz@phys.ethz.ch [Institute for Theoretical Physics, ETH Zurich, Zurich (Switzerland)

    2016-01-15

    We discuss information-theoretic concepts on infinite-dimensional quantum systems. In particular, we lift the smooth entropy formalism as introduced by Renner and collaborators for finite-dimensional systems to von Neumann algebras. For the smooth conditional min- and max-entropy, we recover similar characterizing properties and information-theoretic operational interpretations as in the finite-dimensional case. We generalize the entropic uncertainty relation with quantum side information of Tomamichel and Renner and discuss applications to quantum cryptography. In particular, we prove the possibility to perform privacy amplification and classical data compression with quantum side information modeled by a von Neumann algebra.

  18. Kodierung von Metadaten digitaler Briefeditionen in TEI-XML

    OpenAIRE

    Dumont, Stefan

    2017-01-01

    Folien zu einem Vortrag im Rahmen des Digital-Humanities-Kolloquium an der BBAW am 7.7.2017. Der Vortrag erläutert, ausgehend von editionswissenschaftlichen Entwicklungen der 1980er und 1990er Jahre, wie die "Kopfdaten" eines Briefes nach den Richtlinien der Text Encoding Initiative (TEI) kodiert werden können. Insbesondere wird auf das TEI-Element correspDesc eingegangen und die Kodierung anhand eines Beispiels veranschaulicht. Darüber hinaus wird der Mehrwert von Briefmetadaten sowohl für d...

  19. Turbulence modeling of the Von Karman flow: Viscous and inertial stirrings

    International Nuclear Information System (INIS)

    Poncet, Sebastien; Schiestel, Roland; Monchaux, Romain

    2008-01-01

    The present work considers the turbulent Von Karman flow generated by two counter-rotating smooth flat (viscous stirring) or bladed (inertial stirring) disks. Numerical predictions based on one-point statistical modeling using a low-Reynolds number second-order full stress transport closure (RSM model) are compared to velocity measurements performed at CEA (Commissariat a l'Energie Atomique, France). The main and significant novelty of this paper is the use of a drag force in the momentum equations to reproduce the effects of inertial stirring instead of modeling the blades themselves. The influences of the rotational Reynolds number, the aspect ratio of the cavity, the rotating disk speed ratio and of the presence or not of impellers are investigated to get a precise knowledge of both the dynamics and the turbulence properties in the Von Karman configuration. In particular, we highlighted the transition between the merged and separated boundary layer regimes and the one between the Batchelor [Batchelor, G.K., 1951. Note on a class of solutions of the Navier-Stokes equations representing steady rotationally-symmetric flow. Quat. J. Mech. Appl. Math. 4 (1), 29-41] and the Stewartson [Stewartson, K., 1953. On the flow between two rotating coaxial disks. Proc. Camb. Philos. Soc. 49, 333-341] flow structures in the smooth disk case. We determined also the transition between the one cell and the two cell regimes for both viscous and inertial stirrings

  20. Analyse der pharmazeutischen Versorgungssituation von Patienten mit Psoriasis-Arthritis auf Basis von Routinedaten der Gesetzlichen Krankenversicherung.

    Science.gov (United States)

    Sondermann, Wiebke; Ventzke, Julia; Matusiewicz, David; Körber, Andreas

    2018-03-01

    Die Psoriasis-Arthritis (PsA) gehört zu den chronisch entzündlichen Gelenkerkrankungen. Trotz zahlreicher versorgungswissenschaftlicher Studien in Deutschland liegen zur pharmazeutischen Versorgungssituation von PsA-Patienten bisher kaum aktuelle Ergebnisse vor. Mit Hilfe einer systematischen Literaturrecherche sowie anhand von Routinedaten der Allgemeinen Ortskrankenkasse (AOK) Rheinland/Hamburg wird ein aktueller Überblick über die pharmazeutische Versorgung von PsA-Patienten in Deutschland gegeben. Selektiert wurden Versicherte aus dem ambulanten und stationären Bereich, die im 1. und 2. Quartal des Jahres 2014 die gesicherte Abrechnungsdiagnose Psoriasis-Arthritis L40.5+ aufwiesen. Anschließend wurden auf Basis dieser "vorab definierten" Kohorte die Arzneimitteldaten für 5 Jahre (01.01.2010-31.12.2014) abgerufen. Es konnten insgesamt n  =  3205 Versicherte (45 % männlich, 55 % weiblich) der AOK Rheinland/Hamburg mit einer gesicherten PsA-Diagnose selektiert werden. Das Durchschnittsalter betrug 58,9 Jahre. 53,7 % der PsA-Patienten wurden mit systemischen PsA-relevanten Arzneimitteln versorgt. Nichtsteroidale Antirheumatika (NSAR) wurden am häufigsten verordnet, gefolgt von systemischen Glucocorticoiden. Von den selektierten PsA-Patienten, die eine Systemtherapie erhielten, wurden 72,1 % mittels einer Disease-modifying-antirheumatic-Drug (DMARD)-Monotherapie behandelt, gefolgt von der Kombinationstherapie aus DMARDs und Biologika (20,9 %). Die pharmakologische Therapie der PsA muss eine Gewährleistung zwischen adäquater Versorgung der PsA mit Verhinderung der Krankheitsprogression und ökonomischer Verantwortung darstellen. © 2018 Deutsche Dermatologische Gesellschaft (DDG). Published by John Wiley & Sons Ltd.

  1. Theory of rubber friction and traction properties of car tyres; Theorie der Gummireibung und Traktionseigenschaften von Reifen

    Energy Technology Data Exchange (ETDEWEB)

    Klueppel, M.; Alshuth, T.; Schuster, R.H. [Deutsches Inst. fuer Kautschuktechnologie e.V., Hannover (Germany)

    1998-12-31

    ABS braking on dry and wet roads involves different mechanisms of rubber friction on rough surfaces. This improves car safety in terms of higher manoeuvrability and shorter braking lengths especially on wet roads. Current research focuses on optimisation of tyrecontact surface materials with better traction characteristics and lower rolling resistance. Laboratory predictions of the traction properties of tyre faces must be based on fundamental knowledge of the local sliding phenomena in the tyre contact surface and the resulting energy dissipation during ABS braking. This contribution therefore attempts to relate the elementary mechanisms of tyre mechanics in ABS braking processes to theoretical concepts of rubber friction on rough surfaces. [Deutsch] Beim ABS-Bremsen auf trockenen und nassen Strassen werden unterschiedliche Mechanismen der Gummireibung auf rauhen Oberflaechen wirksam. In der Summe bewirkt dies eine hoehere Fahrsicherheit, da neben der Manoevrierfaehigkeit des Autos auch der Bremsweg, vor allem auf nassen Strassen, verkuerzt sein kann. In diesem Zusammenhang wird zur Zeit verstaerkt an einer Optimierung von Laufflaechenmaterialien durch den Einsatz von massgeschneiderten Loesungs-SBR-Typen in Verbindung mit gefaellten Kieselsaeuren gearbeitet, wodurch neben einer Verbesserung der Traktionseigenschaften beim ABS-Bremsen auch eine Verringerung des Rollwiderstandes erreicht wird. Fuer Laborvorhersagen der Traktionseigenschaften von Reifenlaufflaechen ist ein grundlegendes Verstaendnis der lokalen Gleitphaenomene in der Reifenaufstandsflaeche und der damit verbundenen Energiedissipation beim ABS-Bremsen erforderlich. In dieser Arbeit wird deshalb angestrebt, die elementaren Mechanismen der Reifenmechanik beim ABS-Bremsen mit theoretischen Konzepten der Gummireibung auf rauhen Oberflaechen in Verbindung zu bringen. (orig.)

  2. Entwicklung von Antikörper-Mikroarray : von Biophysik der Mikrospot-Reaktion bis zur Hochdurchsatzanalyse der Proteine

    OpenAIRE

    Kusnezow, Wlad

    2007-01-01

    Obwohl Protein-Mikroarrays ursprünglich aus dem gut entwickelten und fest etablierten DNA-Pendant entstanden sind, repräsentierte jedoch die Umstellung der Mikroarray-Technik von der DNA- auf die Proteinanalyse aufgrund der enormen physikalisch-chemischen Variabilität der Proteine, deren relativ niedrigen Stabilität und der komplexen Mikrospot-Kinetik eine große technologische Herausforderung. Deshalb setzt das Vorhaben, die Technik der Antikörper–Mikroarrays von ihrem konzeptuellen Zustand a...

  3. Automatische Ableitung und Anwendung von Regeln für die Rekonstruktion von Fassaden aus heterogenen Sensordaten

    OpenAIRE

    Becker, Susanne

    2011-01-01

    3D-Stadtmodelle finden seit einigen Jahren in immer stärkerem Maß und in den verschiedensten Bereichen Verwendung. Sie bilden unter anderem die Grundlage bei Stadtplanungen, für virtuelle Stadtrundgänge oder für die Berechnung von Simulationen. Internetdiensten wie Google Earth oder Microsoft Bing Maps ist es zu verdanken, dass 3D-Darstellungen von Gebäuden mittlerweile auch für eine breite Öffentlichkeit allgegenwärtig sind. Die erhöhte Nachfrage nach 3D-Gebäudemodellen verlangt nach effizie...

  4. Von-Neumann and Beyond: Memristor Architectures

    KAUST Repository

    Naous, Rawan

    2017-05-01

    An extensive reliance on technology, an abundance of data, and increasing processing requirements have imposed severe challenges on computing and data processing. Moreover, the roadmap for scaling electronic components faces physical and reliability limits that hinder the utilization of the transistors in conventional systems and promotes the need for faster, energy-efficient, and compact nano-devices. This work thus capitalizes on emerging non-volatile memory technologies, particularly the memristor for steering novel design directives. Moreover, aside from the conventional deterministic operation, a temporal variability is encountered in the devices functioning. This inherent stochasticity is addressed as an enabler for endorsing the stochastic electronics field of study. We tackle this approach of design by proposing and verifying a statistical approach to modelling the stochastic memristors behaviour. This mode of operation allows for innovative computing designs within the approximate computing and beyond Von-Neumann domains. In the context of approximate computing, sacrificing functional accuracy for the sake of energy savings is proposed based on inherently stochastic electronic components. We introduce mathematical formulation and probabilistic analysis for Boolean logic operators and correspondingly incorporate them into arithmetic blocks. Gate- and system-level accuracy of operation is presented to convey configurability and the different effects that the unreliability of the underlying memristive components has on the intermediary and overall output. An image compression application is presented to reflect the efficiency attained along with the impact on the output caused by the relative precision quantification. In contrast, in neuromorphic structures the memristors variability is mapped onto abstract models of the noisy and unreliable brain components. In one approach, we propose using the stochastic memristor as an inherent source of variability in

  5. Der Zusammenhang von Partnermarktopportunitäten aus dem Freundeskreis und der Stabilität von Paarbeziehungen : Eine Analyse mit den Daten des Partnermarktsurvey

    OpenAIRE

    Häring, Armando

    2014-01-01

    "Der Beitrag analysiert den Zusammenhang zwischen Partnermarktoportunitäten aus dem Freundeskreis und der Stabilität von Paarbeziehungen. Unter Verwendung des theoretischen Konzepts der Theorie der Interaktionsgelegenheiten sowie von Annahmen der Austauschtheorie und der Familienökonomie, werden mögliche Zusammenhänge zwischen gemeinsamen Freundeskreisen mit dem Partner, Partnermarktgelegenheiten aus dem Freundeskreis (sex ratio) und der Stabilität von Paarbeziehungen diskutiert. Der Beitrag ...

  6. von Kármán swirling flow between a rotating and a stationary smooth disk: Experiment

    Science.gov (United States)

    Mukherjee, Aryesh; Steinberg, Victor

    2018-01-01

    Precise measurements of the torque in a von Kármán swirling flow between a rotating and a stationary smooth disk in three Newtonian fluids with different dynamic viscosities are reported. From these measurements the dependence of the normalized torque, called the friction coefficient, on Re is found to be of the form Cf=1.17 (±0.03 ) Re-0.46±0.003 where the scaling exponent and coefficient are close to that predicted theoretically for an infinite, unshrouded, and smooth rotating disk which follows from an exact similarity solution of the Navier-Stokes equations, obtained by von Kármán. An error analysis shows that deviations from the theory can be partially caused by background errors. Measurements of the azimuthal Vθ and axial velocity profiles along radial and axial directions reveal that the flow core rotates at Vθ/r Ω ≃0.22 (up to z ≈4 cm from the rotating disk and up to r0/R ≃0.25 in the radial direction) in spite of the small aspect ratio of the vessel. Thus the friction coefficient shows scaling close to that obtained from the von Kármán exact similarity solution, but the observed rotating core provides evidence of the Batchelor-like solution [Q. J. Mech. Appl. Math. 4, 29 (1951), 10.1093/qjmam/4.1.29] different from the von Kármán [Z. Angew. Math. Mech. 1, 233 (1921), 10.1002/zamm.19210010401] or Stewartson [Proc. Camb. Philos. Soc. 49, 333 (1953), 10.1017/S0305004100028437] one.

  7. Von Kármán between Aachen and Pasadena

    Science.gov (United States)

    Krause, Egon; Kalkmann, Ulrich

    2013-05-01

    In the Introduction the reader is referred back to the academic ceremonials held after Theodore von Kármán's death in Aachen in May 1963. His work as the first director of the Aerodynamisches Institut (Institute of Aerodynamics) of the RWTH Aachen University of Technology from 1913 on and his initiative to re-establish international cooperation after World War I, resulting in the International Union of Theoretical and Applied Mechanics (IUTAM), are commented on. The following chapter describes von Kármán's relation to his former teacher Ludwig Prandtl. Some of von Kármán's scientific contributions during his time in Aachen are briefly reviewed. Thereafter, his first contacts to the California Institute of Technology are covered. Finally, the scientific and political circumstances, which led to von Kármán's decision to leave Germany in the early thirties, are elucidated in some detail. The English translation of the titles of the Aachen papers is given in Appendix I.

  8. Wernher von Braun: Reflections on His Contributions to Space Exploration

    Science.gov (United States)

    Goldman, Arthur E.

    2012-01-01

    In 1950, Dr. Wernher von Braun and approximately 100 of his team members came to Huntsville, Alabama, to begin work with the Army on what would later become America's historic space program. He would later serve as the first director of the Marshall Space Flight Center and led the development of the Saturn V launch vehicle that launched seven crewed American mission to the moon, as well as America s first space station, Skylab. Von Braun is best known for his team s technical achievements. He realized his dream of exploring outer space by helping place humans on the moon. His engineering and managerial talent during the Apollo era had contributed to a technological revolution. He was by all accounts a good engineer, but he was only one among many. What set Von Braun apart were his charisma, his vision, and his leadership skills. He inspired loyalty and dedication in the people around him. He understood the importance of communicating his vision to his team, to political and business leaders and the public. Today, the Marshall Center continues his vision by pursuing engineering and scientific projects that will continue to open space to exploration. This presentation will discuss Von Braun's impact on Huntsville, the Marshall Center, the nation and the world and look at his contributions in context of where world space exploration is today.

  9. Nonlinear von Neumann equations for quantum dissipative systems

    International Nuclear Information System (INIS)

    Messer, J.; Baumgartner, B.

    1978-01-01

    For pure states nonlinear Schroedinger equations, the so-called Schroedinger-Langevin equations are well-known to model quantum dissipative systems of the Langevin type. For mixtures it is shown that these wave equations do not extend to master equations, but to corresponding nonlinear von Neumann equations. Solutions for the damped harmonic oscillator are discussed. (Auth.)

  10. Nonlinear von Neumann equations for quantum dissipative systems

    International Nuclear Information System (INIS)

    Messer, J.; Baumgartner, B.

    For pure states nonlinear Schroedinger equations, the so-called Schroedinger-Langevin equations are well-known to model quantum dissipative systems of the Langevin type. For mixtures it is shown that these wave equations do not extend to master equations, but to corresponding nonlinear von Neumann equations. Solutions for the damped harmonic oscillator are discussed. (Author)

  11. Dr. von Braun With a Model of a Launch Vehicle

    Science.gov (United States)

    1950-01-01

    Dr. von Braun stands beside a model of the upper stage (Earth-returnable stage) of the three-stage launch vehicle built for the series of the motion picture productions of space flight produced by Walt Disney in the mid-1950's.

  12. Ernst von Glasersfeld's Radical Constructivism and Truth as Disclosure

    Science.gov (United States)

    Joldersma, Clarence W.

    2011-01-01

    In this essay Clarence Joldersma explores radical constructivism through the work of its most well-known advocate, Ernst von Glasersfeld, who combines a sophisticated philosophical discussion of knowledge and truth with educational practices. Joldersma uses Joseph Rouse's work in philosophy of science to criticize the antirealism inherent in…

  13. Eritrea : Von der Befreiung zur Unterdrückung

    NARCIS (Netherlands)

    van Reisen, Mirjam; Buck, K.D.

    2015-01-01

    Über das heutige Eritrea ist nur wenig bekannt. Als das kleine Land am Horn von Afrika 1993 die Unabhängigkeit erlangte, waren nicht nur im Land selbst die Hoffnungen groß, dass nach dem dreißig Jahre dauernden Befreiungskampf gegen Äthiopien eine bessere und friedliche Zukunft für alle beginnen

  14. Sakslased tulevad! Ärevad ajad Tallinnas Von Krahli Teatris

    Index Scriptorium Estoniae

    2001-01-01

    Von Krahli Teater ja Showcase Beat Le Mot valmistuvad oma esimeseks koostööprojektiks - lavastuseks "Pirates", kus osalevad mõlema teatri näitlejad ja tehnikud. Ühisprojekti toetavad Goethe Instituut, Hamburgi Linnavalitsus ja Eesti Kultuurkapital

  15. Professor Oberth and Dr. von Braun at ARS Banquet

    Science.gov (United States)

    1961-01-01

    Dr. Wernher von Braun holds the coveted Hermarn Oberth award presented to him by Professor Oberth during the banquet hosted by the Alabama Section of the American Rocket Society (ARS), on October 19, 1961. The Oberth award was given for outstanding technical contributions to the field of astronautics or for the promotion and advancement of astronautical sciences.

  16. Semiparametric Bernstein–von Mises for the error standard deviation

    NARCIS (Netherlands)

    Jonge, de R.; Zanten, van J.H.

    2013-01-01

    We study Bayes procedures for nonparametric regression problems with Gaussian errors, giving conditions under which a Bernstein–von Mises result holds for the marginal posterior distribution of the error standard deviation. We apply our general results to show that a single Bayes procedure using a

  17. Semiparametric Bernstein-von Mises for the error standard deviation

    NARCIS (Netherlands)

    de Jonge, R.; van Zanten, H.

    2013-01-01

    We study Bayes procedures for nonparametric regression problems with Gaussian errors, giving conditions under which a Bernstein-von Mises result holds for the marginal posterior distribution of the error standard deviation. We apply our general results to show that a single Bayes procedure using a

  18. De identiteit van Portulaca advena Reichg. & Von Poellnitz

    NARCIS (Netherlands)

    Geesink, R.

    1969-01-01

    Portulaca advena Reichg. & Von Poellnitz (1939), based on adventive specimens collected near Erp, prov. N.-Brabant, Netherlands, and afterwards cultivated in a garden at Nijmegen, appears to be identical with the South American P. papulosa Schldl. (1853). The adventive species of Portulaca found in

  19. Alexander von Humboldt's invention of the natural landscape

    NARCIS (Netherlands)

    Kwa, C.

    2005-01-01

    Landscape took on a new meaning through the new science of plant geography of Alexander von Humboldt (1769-1857). In the seventeenth and eighteenth centuries, "landscape" was foremost a painterly genre. Slowly, painted landscapes came to bear on natural surroundings, but by 1800 it was still not

  20. KK -theory and spectral flow in von Neumann algebras

    DEFF Research Database (Denmark)

    Kaad, Jens; Nest, Ryszard; Rennie, Adam

    2012-01-01

    We present a definition of spectral flow for any norm closed ideal J in any von Neumann algebra N. Given a path of selfadjoint operators in N which are invertible in N/J, the spectral flow produces a class in Ko (J). Given a semifinite spectral triple (A, H, D) relative to (N, t) with A separable...

  1. Enfermedad de Von Gierke: Reporte de tres casos

    Directory of Open Access Journals (Sweden)

    E. Espinosa

    2001-07-01

    Full Text Available La enfermedad de Von Gierke es un defecto en la glucosa 6 fosfatasa, degrada el glucógeno en el hígado, riñón e intestino. Asociada con hipoglicemia, acidosis láctica e hiperuricemia.

  2. A von Neumann type inequality for certain domains in Cn

    Czech Academy of Sciences Publication Activity Database

    Ambrozie, Calin-Grigore; Timotin, D.

    2002-01-01

    Roč. 131, č. 3 (2002), s. 859-869 ISSN 0002-9939 R&D Projects: GA ČR GA201/03/0041 Institutional research plan: CEZ:AV0Z1019905 Keywords : von Neumann inequality * multioperators * Nevanlinna-Pick problem Subject RIV: BA - General Mathematics Impact factor: 0.334, year: 2002

  3. Characterizing ξ-Lie Multiplicative Isomorphisms on Von Neumann Algebras

    Directory of Open Access Journals (Sweden)

    Yamin Song

    2014-01-01

    Full Text Available Let ℳ and be von Neumann algebras without central summands of type I1. Assume that ξ∈ℂ with ξ≠1. In this paper, all maps Φ:ℳ→ satisfying ΦAB-ξBA=ΦAΦB-ξΦBΦ(A are characterized.

  4. A bicategorical approach to Morita equivalence for Von Neumann algebras

    NARCIS (Netherlands)

    R.M. Brouwer (Rachel)

    2003-01-01

    textabstractWe relate Morita equivalence for von Neumann algebras to the ``Connes fusion'' tensor product between correspondences. In the purely algebraic setting, it is well known that rings are Morita equivalent if and only if they are equivalent objects in a bicategory whose 1-cells are

  5. A paradox of rationality à la von Neumann-Morgenstern

    NARCIS (Netherlands)

    Ismail, M.S.

    2015-01-01

    We show that there are games and decision situations in which it is not possible for the decision maker to be rational a la von Neumann-Morgenstern in both situations simultaneously, which is the source of the paradox presented in this note. We provide an assumption which is the necessary and

  6. Extensions of von Neumann's method for generating random variables

    International Nuclear Information System (INIS)

    Monahan, J.F.

    1979-01-01

    Von Neumann's method of generating random variables with the exponential distribution and Forsythe's method for obtaining distributions with densities of the form e/sup -G//sup( x/) are generalized to apply to certain power series representations. The flexibility of the power series methods is illustrated by algorithms for the Cauchy and geometric distributions

  7. Computed tomography of von Meyenburg complex simulating micro-abscesses

    International Nuclear Information System (INIS)

    Sada, P.N.; Ramakrishna, B.

    1994-01-01

    A case is presented of a bile duct hamartoma in a 44 year old man being evaluated for abdominal pain. The computed tomography (CT) findings suggested micro-abscesses in the liver and a CT guided tru-cut biopsy showed von Meyenburg complex. 9 refs., 3 figs

  8. Ueber die arten und den Skelettbau von Culcita

    NARCIS (Netherlands)

    Hartlaub, Clemens

    1892-01-01

    Das Genus Culcita Agass. zählt durch die merkwürdige Form und die ansehnliche Grösse seiner Arten zu den interessantesten Asteriden, und gut conservirte Exemplare davon gehören zu den Zierden unsrer Museen. Um so bedauerlicher erschien es mir, als ich vor einiger Zeit den Versuch machte die von

  9. Mollusken aus posttertiären Schichten von Celebes

    NARCIS (Netherlands)

    Schepman, M.M.

    1912-01-01

    Die im Folgenden behandelten Mollusken stammen aus der Nähe von Kajoe ragi auf Celebes, woselbst sie durch R. FENNEMA aus denselben Schichten ausgelesen wurden, aus denen früher durch J. G. DE MAN einige brachyure Krebse beschrieben sind. Es darf deswegen betreffs näherer Angaben über die Herkunft

  10. Die Korallenfauna des Perm von Timor und die permische Vereisung

    NARCIS (Netherlands)

    Gerth, H.

    1926-01-01

    Bei den zahlreichen Rekonstruktionen der klimatologischen Verhältnisse, die man für das Ende des Palaeozoikums gemacht hat, ist man fast immer von der Kohlenbildung, der Florenverbreitung und den Vereisungserscheinungen ausgegangen. Der marinen Tierwelt hat man bei der Behandlung dieser Fragen meist

  11. Ueber einige Entwicklungsstadien von Rhopilema hispidum (Vanhoeffen) Maas

    NARCIS (Netherlands)

    Stiasny, G.

    1933-01-01

    Gelegentlich der Durchsicht einiger älterer Planktonfänge aus dem malayischen Archipel in den Sammlungen des Rijks Museum van Natuurlijke Historie in Leiden fanden sich zahlreiche Entwicklungsstadien von Rhopilema hispidum (VANH.) MAAS vor, über die ich hier kurz berichten will. Ueber die

  12. Fossile Säugethierreste von Java und Japan

    NARCIS (Netherlands)

    Martin, K.

    1884-01-01

    Die Beschreibung eines Stegodontenzahnes von Java in der vorhergehenden Abhandlung dieses Bandes ist die Veranlassung geworden, dass De Koninklijke Natuurkundige Vereeniging in Nederlandsch Indië eine grosse Sammlung fossiler Säugethierreste dem Geologischen Museum in Leiden übersandte. Es befinden

  13. Minimum Moduli in Von Neumann Algebras | Gopalraj | Quaestiones ...

    African Journals Online (AJOL)

    In this paper we answer a question raised in [12] in the affirmative, namely that the essential minimum modulus of an element in a von. Neumann algebra, relative to any norm closed two-sided ideal, is equal to the minimum modulus of the element perturbed by an element from the ideal. As a corollary of this result, we ...

  14. Die Rolle von Osteoklasten bei der arthritischen Knochenerosion

    Directory of Open Access Journals (Sweden)

    Schett G

    2003-01-01

    Full Text Available Knöcherne Erosionen stellen eine wesentliche Ursache für die funktionelle Einschränkung von Patienten mit rheumatoider Arthritis dar. Bis vor kurzem war über den Pathomechanismus dieser Veränderungen nur wenig bekannt. Dieser Review faßt die letzten Erkenntnisse über die Ausbildung einer Knochenschädigung bei entzündlichen Gelenkerkrankungen zusammen und fokussiert insbesondere die Rolle von Osteoklasten. Es wird ein Überblickzu den Hinweisen für eine Präsenz von Osteoklasten im entzündlich veränderten Gelenk gegeben. Weiters werden die Faktoren diskutiert, die die Osteoklastogenese im Rahmen einer Gelenkentzündung aktivieren können. Hier wird im besonderen auf die Rolle von Receptor-Activator of Nuclear Factor Kappa B Ligand (RANKL eingegangen. Im weiteren werden die Auswirkungen einer Osteoklastenhemmung in den verschiedenen Arthritismodellen zusammengefaßt und Möglichkeiten einer therapeutischen Nutzung bei rheumatoider Arthritis diskutiert.

  15. Die filmstilistische Darstellung von Klaras Gehbehinderung im Kinderfilm "Heidi"

    Directory of Open Access Journals (Sweden)

    Maria Ohrfandl

    2016-09-01

    Full Text Available Dieser Beitrag soll die Forschungslücke zur Darstellung von Behinderungen speziell im Kinderfilm im deutschsprachigen Raum füllen. Auf Basis einer neoformalistisch orientierten Filmanalyse nach Bordwell und Thompson (2008, wird anhand von drei Filmsequenzen eine mögliche Lesart des Kinderfilms "Heidi" (Marcus 2005 entwickelt, um die filmstilistische Darstellung der Gehbehinderung des Mädchens Klara zu untersuchen. Die Ergebnisse werden mit theoretischen Überlegungen zur Problematik der Begriffsbestimmung von Körperbehinderung sowie zur Mobilität und Selbstbestimmung von Menschen mit Körperbehinderungen in Bezug gesetzt. Dabei zeigt sich im Wesentlichen, dass im Kinderfilm "Heidi" (Marcus 2005 Klaras Gehbehinderung als 'heilbare Krankheit' und der Rollstuhl als Einschränkung von Mobilität begriffen wird. Außerdem unterliegt Klara aufgrund ihrer Körperbehinderung überwiegend der Fremdbestimmung von Erwachsenen. Zur Klärung wahrscheinlicher filmischer Bildungspotenziale werden die Ergebnisse schließlich anhand der von Jörissen und Marotzki (2009 entwickelten Orientierungsdimensionen "Wissens-, Handlungs-, Grenz- und Biographiebezug" diskutiert. This article aims to bridge a knowledge gap by showing ways of representing disabilities in the German children film genre. Using Bordwell and Thomson's (2008 neoformalistically orientated film analysis approach, the movie "Heidi" (Marcus 2005 is analysed. Bordwell and Thompson's (2008 method is applied to three sequences of "Heidi" in order to present an interpretation and to discuss the representation of Clara's walking impediment. The results are then associated with theoretical considerations regarding the mobility and self-determination of people with disabilities and problematic definitions of the term 'physical disability'. It is shown that characters in the children's film "Heidi" (Marcus 2005 regard Clara's walking impediment as a 'curable disease' and the wheelchair as a limitation

  16. Optimierung der Gesichtsklassifikation bei der Erkennung von Akromegalie

    Directory of Open Access Journals (Sweden)

    Frohner R

    2013-01-01

    Full Text Available In vorausgegangenen Studien konnte gezeigt werden, dass eine Gesichtsklassifikation mittels Gesichtsphotographien zur Diagnostik von Akromegalie mit guten Ergebnissen eingesetzt werden kann. In diesem Artikel werden die grundlegende Vorgehensweise der Klassifikation mittels der Software FIDA erläutert sowie Optimierungsansätze mit dem Ziel diskutiert, diese Methode näher an den klinischen Einsatz zu bringen. Die Gesichtsklassifikation basiert auf „Knotenpunkten“, die verteilt über die jeweilige Frontal- und/oder Seitenansicht des Gesichts platziert werden und den so genannten „Graphen“ bilden. Mittels mathematischer Verfahren erfolgt eine Analyse der zugrunde liegenden Textur des Bildes sowie die Auswertung geometrischer Informationen. Untersucht wird, wie sich die Reduktion von als irrelevant eingestuften Knoten auf das Klassifikationsergebnis auswirkt. Ebenso wird untersucht, wie sich neu definierte Knoten, die die typischen morphologischen Veränderungen der akromegalen Erkrankung im Gesicht berücksichtigen, auf die Klassifizierungsergebnisse auswirken. Die interne Validierung erfolgt an einem Datenset bestehend aus 57 an Akromegalie erkrankten Probanden (29 weiblich, 28 männlich sowie 59 Kontrollen (29 weiblich, 30 männlich. Die externe Validierung wird an einer weiteren Stichprobe gemessen, die zum Zeitpunkt der Präsentation auf der Tagung der European Neuroendocrine Association 2012 in Wien 13 akromegale Patienten (7 weiblich, 6 männlich sowie 45 Kontrollen (25 weiblich, 20 männlich umfasste. Die Datenbank wird ständig durch neue Probanden aus verschiedenen Quellen erweitert. Erste Ergebnisse zeigen, dass die Verwendung von Graphen mit reduzierten Knoten und von neuen Sets von Knoten unter Einbeziehung typischer morphologischer Veränderungen des Gesichts die Klassifizierung weiter verbessert. Diese Ergebnisse ermutigen zu weiteren Untersuchungen an einer erweiterten Datenbank.

  17. Eine selbstkonsistente Carleman Linearisierung zur Analyse von Oszillatoren

    Directory of Open Access Journals (Sweden)

    H. Weber

    2017-09-01

    Full Text Available Die Analyse nichtlinearer dynamischer Schaltungen ist bis heute eine herausfordernde Aufgabe, da nur selten analytische Lösungen angegeben werden können. Daher wurden eine Vielzahl von Methoden entwickelt, um eine qualitative oder quantitative Näherung für die Lösungen der Netzwerkgleichung zu erhalten. Oftmals wird beispielsweise eine Kleinsignalanalyse mit Hilfe einer Taylorreihe in einem Arbeitspunkt durchgeführt, die nach den Gliedern erster Ordnung abgebrochen wird. Allerdings ist diese Linearisierung nur in der Nähe des stabilen Arbeitspunktes für hyperbolische Systeme gültig. Besonders für die Analyse des dynamischen Verhaltens von Oszillatoren treten jedoch nicht-hyperbolische Systeme auf, sodass diese Methode nicht angewendet werden kann Mathis(2000. Carleman hat gezeigt, dass nichtlineare Differentialgleichungen mit polynomiellen Nichtlinearitäten in ein unendliches System von linearen Differentialgleichungen transformiert werden können Carleman(1932. Wird das unendlichdimensionale Gleichungssystem für numerische Zwecke abgebrochen, kann bei Oszillatoren der Übergang in eine stationäre Schwingung (Grenzzyklus nicht wiedergegeben werden.In diesem Beitrag wird eine selbstkonsistente Carleman Linearisierung zur Untersuchung von Oszillatoren vorgestellt, die auch dann anwendbar ist, wenn die Nichtlinearitäten keinen Polynomen entsprechen. Anstelle einer linearen Näherung um einen Arbeitspunkt, erfolgt mit Hilfe der Carleman Linearisierung eine Approximation auf einem vorgegebenen Gebiet. Da es jedoch mit der selbstkonsistenten Technik nicht möglich ist, das stationäre Verhalten von Oszillatoren zu beschreiben, wird die Berechnung einer Poincaré-Abbildung durchgeführt. Mit dieser ist eine anschließende Analyse des Oszillators möglich.

  18. Eine selbstkonsistente Carleman Linearisierung zur Analyse von Oszillatoren

    Science.gov (United States)

    Weber, Harry; Mathis, Wolfgang

    2017-09-01

    Die Analyse nichtlinearer dynamischer Schaltungen ist bis heute eine herausfordernde Aufgabe, da nur selten analytische Lösungen angegeben werden können. Daher wurden eine Vielzahl von Methoden entwickelt, um eine qualitative oder quantitative Näherung für die Lösungen der Netzwerkgleichung zu erhalten. Oftmals wird beispielsweise eine Kleinsignalanalyse mit Hilfe einer Taylorreihe in einem Arbeitspunkt durchgeführt, die nach den Gliedern erster Ordnung abgebrochen wird. Allerdings ist diese Linearisierung nur in der Nähe des stabilen Arbeitspunktes für hyperbolische Systeme gültig. Besonders für die Analyse des dynamischen Verhaltens von Oszillatoren treten jedoch nicht-hyperbolische Systeme auf, sodass diese Methode nicht angewendet werden kann Mathis (2000). Carleman hat gezeigt, dass nichtlineare Differentialgleichungen mit polynomiellen Nichtlinearitäten in ein unendliches System von linearen Differentialgleichungen transformiert werden können Carleman (1932). Wird das unendlichdimensionale Gleichungssystem für numerische Zwecke abgebrochen, kann bei Oszillatoren der Übergang in eine stationäre Schwingung (Grenzzyklus) nicht wiedergegeben werden. In diesem Beitrag wird eine selbstkonsistente Carleman Linearisierung zur Untersuchung von Oszillatoren vorgestellt, die auch dann anwendbar ist, wenn die Nichtlinearitäten keinen Polynomen entsprechen. Anstelle einer linearen Näherung um einen Arbeitspunkt, erfolgt mit Hilfe der Carleman Linearisierung eine Approximation auf einem vorgegebenen Gebiet. Da es jedoch mit der selbstkonsistenten Technik nicht möglich ist, das stationäre Verhalten von Oszillatoren zu beschreiben, wird die Berechnung einer Poincaré-Abbildung durchgeführt. Mit dieser ist eine anschließende Analyse des Oszillators möglich.

  19. Otto von Habsburg : III maailmasõda on läbi / Otto von Habsburg ; interv. Marianne Mikko

    Index Scriptorium Estoniae

    Habsburg, Otto von, 1912-2011

    2002-01-01

    Otto von Habsburg vastab küsimustele, mis puudutavad Euroopa konvendi presidendi teadet, et Türgi koht ei ole EL-is, Iraagi võimalikku ründamist, Hiina ja Venemaa suhteid, Tšetšeeniat, tshetsheene ja terrorismi, Venemaa, EL-i ja USA suhteid, III maailmasõda, Eesti Vabariigi tulevikku

  20. Zum 215. Gebutstag von Admiral Ferdinand Baron von Wrangell : (29. Dezember 1797 - 25. 25. Mai 1870) / Peter Krienitz

    Index Scriptorium Estoniae

    Krienitz, Peter

    2012-01-01

    Admiral Ferdinand Baron von Wrangellist tema 215. sünniaastapäeva puhul. Silmapaistavast Kirde-Siberi uurijast. Tema poliitilisest tegevusest ja elust Roela mõisas. Ferdinand Baroni poolt seatud viisil tähistati jõulusid Roelas kuni 1944. aasta lõpuni.

  1. Abschätzung des Einflusses von Parameterunsicherheiten bei der Planung und Auswertung von Tracertests unter Verwendung von Ensembleprognosen

    Science.gov (United States)

    Klotzsch, Stephan; Binder, Martin; Händel, Falk

    2017-06-01

    While planning tracer tests, uncertainties in geohydraulic parameters should be considered as an important factor. Neglecting these uncertainties can lead to missing the tracer breakthrough, for example. One way to consider uncertainties during tracer test design is the so called ensemble forecast. The applicability of this method to geohydrological problems is demonstrated by coupling the method with two analytical solute transport models. The algorithm presented in this article is suitable for prediction as well as parameter estimation. The parameter estimation function can be used in a tracer test for reducing the uncertainties in the measured data which can improve the initial prediction. The algorithm was implemented into a software tool which is freely downloadable from the website of the Institute for Groundwater Management at TU Dresden, Germany.

  2. DIE SPRACHE VON "BAŠĆANSKA PLOČA" (DIE STEINTAFEL VON BAŠKA

    Directory of Open Access Journals (Sweden)

    Stjepan Damjanović

    1990-01-01

    Full Text Available In einer Mehrzahl von Abhandlungen über Bašćanska ploča berücksichtigen die Verfasser auch die Sprache, in der Regel kurz, nur in einem oder zwei Sätzen. Die größten Bemühungen sind auf die Rekonstruirung der unlesbaren Teilen gerichtet, dagegen nicht weinger interessanter lesbarer Teil regte eine Sprachanalyse selten an. Gewöhnlich wird festgestellt, daß die Tafel in der kroatischen Sprache geschrieben ist, während die philologisch gut unterrichtete Forscher vermeiden diesartige Nenunngen, indem sie das Vorhandensein der altslawischen und altkroatischen Sprachelemente entdeckten. Man versuchte noch nicht in einer Analyse sprachliche Grundschichte und darauf geschichtete Sprachelemente zu bestimmen. Nach dem ersten Eindruck wurde bestimmt, ob es sich um "die kroatische Srpache mit den Elementen der alten slawischen liturgischen Sprache" handelt oder um "die altslawische in der manche kroatische Spracheigenschaften hereingekommen sind". Die Analyse mancher Spracheinzelheiten (Halblaute und "Jat" weist auf altslawische Grundschicht hin. Der Verfasser hat sich trotzdem nicht entschieden den Fachausdruck "kroatische Redaktion des altslawischen" zu verwenden, weil er neue Analyse und neue Begriffsbestimmungen als nötig hält, wie z.B. "Redaktion", "Rezension" usw, um mit Sicherkeit sagen zu können, ob es um kroatische Redaktion des altslawischen oder um andere Formen der altslawischen - alt kroatischen Interferenz geht.

  3. Digitale Rekonstruktion von historischem Bibliotheksgut. Projektvorstellung Leibniz-Fragmente und Massendigitalisierung von Flachware

    Directory of Open Access Journals (Sweden)

    Matthias Wehry

    2017-12-01

    Full Text Available Der Universalgelehrte Gottfried Wilhelm Leibniz verwendete eine besondere Form der Wissensordnung: Teile seiner Manuskripte und Arbeitspapiere, z.B. Abschriften und Exzerpte, wurden von ihm zerschnitten und in einem so genannten „Zettel-Schrancken“, einem großen Zettelkasten, geordnet. Im vorgestellten Projekt wurde ein automatisiertes virtuelles Assistenzsystem erarbeitet, um die ursprünglichen Zusammenhänge der Notata im Augenblick ihrer Entstehung wiederherzustellen. Das Ergebnis des Projektes ist ein innovatives Massenverfahren zum Puzzeln und Scannen historischer handschriftlicher Dokumente. The polymath Gottfried Wilhelm Leibniz used a specific technique for knowledge organisation: He cut parts of his manuscripts and working papers, e.g., copies and excerpts, in pieces and filed them systematically in a so called “Zettel-Schrancken”, a hugh slipbox. In the project presented in this paper, an automated virtual reconstruction of the notes’ initial context at the moment of origin was developed. The result of the project is an innovative mass processing method for puzzling and scanning historical handwritten documents

  4. Alternative Regulierungsansätze im Kontext der Better Regulation Agenda : eine Analyse von Konzepten, Potenzialen und Erfolgsfaktoren von Regulierung im Schatten staatlicher Hierarchie

    OpenAIRE

    Denker, Philipp

    2008-01-01

    Der vorliegende Beitrag untersucht das Potential und die Bedingungen alternativer Regulierungsformen vor dem Hintergrund von Better Regulation in Deutschland. Nahezu alle EU- und OECD-Staaten betreiben heute umfassende politische Reformprogramme zur Modernisierung der Regulierungsarchitekturen, die unter dem Label Better Regulation subsumiert werden. Die Zielsetzung dieser Programme besteht zum einen in der wirtschaftsfreundlichen Reduktion von Regulierungskosten und zum anderen in der Effekt...

  5. Rezension von: Gabriele Dietze: Weiße Frauen in Bewegung. Genealogien und Konkurrenzen von Race- und Genderpolitiken. Bielefeld: transcript Verlag 2013.

    Directory of Open Access Journals (Sweden)

    Philipp Dorestal

    2014-03-01

    Full Text Available Gabriele Dietze zeichnet das Verhältnis der Kategorien Race und Gender innerhalb der US-amerikanischen Geschichte von der Mitte des 19. Jahrhunderts bis zur Präsidentschaftswahl von Barack Obama nach. Dabei demonstriert sie anhand von zentralen Figuren der weißen Frauenbewegung deren ambivalente Positionen, die oftmals für progressive Inhalte wie das Eintreten für Frauenrechte stehen, gleichzeitig aber dann Anliegen von African Americans nicht artikulieren oder gar zum Schweigen bringen. Ebenso zeigt Dietze mithilfe von Texten einiger schwarzer Autor_innen sowie anhand berühmter Gerichtsprozesse, dass schwarze Emanzipation nicht notwendigerweise mit feministischen Positionen einhergehen musste, sondern sich vielmehr eine Konkurrenzsituation zwischen Race und Gender entspann.

  6. Nutzung und Akzeptanz von E-Commerce

    OpenAIRE

    Schenk, Michael; Wolf, Malthe

    2001-01-01

    Even with the so-called New Markets facing a world-wide break-down and the euphoria around electronic commerce subsequently cooling down market forecasts still predict a great future for electronic commerce. Influenced by electronic communication technologies, business transactions change rapidly. Although business-to-consumer e-commerce is expected to become a successful sales and communication channel world-wide, e-commerce was not accepted by broad consumer groups the way it was hoped for....

  7. The von Auwers reaction - history and synthetic applications.

    Science.gov (United States)

    Dumeunier, Raphaël; Jaeckh, Simon

    2014-01-01

    Dienones obtained from the facile dearomatization of phenols, can be further transformed to semi-benzenes prone to rearomatize in clean, but sometimes unexpected, fashion. Over a hundred years ago, K. von Auwers found that adding Grignards on dienones would lead spontaneously to subsequent dehydration and a novel aromatizing rearrangement. This reaction was ignored for 50 years before Melvin Newman re-investigated these findings, studied the mechanism, and developed variations on the same theme. Since then, despite the tremendous potential of the reactions, those studies were only rarely mentioned, before finally falling into oblivion. This review aims to provide the reader with a detailed history and comprehensive bibliography of the von Auwers rearrangement, some of its synthetic applications, and new unpublished material in the hope to open new perspectives on this forgotten reaction.

  8. Die Ordnung der Weltkulturen. Alexander von Humboldts Ansichten der Kultur

    Directory of Open Access Journals (Sweden)

    Ottmar Ette

    2004-10-01

    Full Text Available Article in German,Abstracts in English, German and Spanish. Focussing Alexander von Humboldt's Vues des Cordillères et Monumens des peuples indigènes de l'Amérique (1810 - 1813 in the context of his monumental work, this essay tries to highlight not only the creation of a new discourse on the Americas but, at the same time, the project(ion of a new order of world cultures. From a transregional perspective, Humboldt's aesthetically most radical book can be fully understood as a musée imaginaire of world cultures whose spatial, temporal, social, literary, frictional, architextual and cultural dimensions allow new insights in one of the most fascinating texts of the early 19th century. Alexander von Humboldt's Vues are creating a transmedial kaleidoscope within a fractal vision of the cultures of the world in the second period of accelerated globalization.

  9. Von eingebetteten Systemen zu Cyber-Physical Systems

    Science.gov (United States)

    Wedde, Rorst F.; Lehnhoff, Sebastian; Rehtanz, Christian; Krause, Olav

    Das Hauptanliegen des Papiers ist, ein Paradigma für Probleme mit neuartigen Integrationsanforderungen für Forschung und Entwicklung in verteilten eingebetteten Echtzeitsystemen zu motivieren und vorzustellen, nämlich den Begriff Cyber-Physical Systems. Bei einer in letzter Zeit stark zunehmenden Anzahl von Realzeitanwendungen können ohne die Berücksichtigung solcher Forderungen keine praktisch brauchbaren Lösungen erwartet werden. Einige Anwendungsfelder werden angesprochen. Im Einzelnen werden dann für Elektroautos, die mit erneuerbaren Energien betrieben werden sollen, einerseits die Management-, verteilte Verhandlungs- und Verteilungsprobleme der benötigten Energie in einem bottom-up Ansatz gelöst. Andererseits wird als Teil unserer Projektarbeit die Bereitstellung von Reserveenergie für den allgemeinen Bedarf durch Autobatterien vorgestellt. Es zeigt sich, dass dies effizienter und wesentlich kurzfristiger in unserem verteilten Vorgehen geschehen kann als in traditionellen Verfahren.

  10. A tribute to Ebba von Fersen Balzan 1957-2008

    OpenAIRE

    Lagana, Louis

    2008-01-01

    Ebba von Fersen Balzan first came to Malta in 1986. She was mostly fascinated by Maltese culture and as an artist she was particularly attracted to the intense light of the Maltese landscape, the colour of the Maltese stone and the megalithic temples. In 1989 she held her first exhibitions in Malta: the first exhibition, in aid of Alternattiva Demokratika, was held at the hotel Phoenicia and another followed at the Museum of Fine Arts in Valletta.

  11. Sonographic findings in the Cruveilhier-von Baumgarten syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Pirschel, J

    1982-07-01

    Portal hypertension is the most common complication of cirrhosis of the liver and leads to a reversal of blood flow and re-opening of pre-formed portal-systemic collaterals. Amongst a variety of possible hepato-fugal collaterals, the Cruveilhier-von Baumgarten syndrome, consisting of the reopening of umbilical veins, is a rare variant. It has been possible to demonstrate this clearly by sonography in 18 patients.

  12. Baron von Zach's business relations with the Munich entrepreneur Joseph von Utzschneider (German Title: Geschäftsbeziehungen des Barons von Zach zu dem Münchner Unternehmer Joseph von Utzschneider)

    Science.gov (United States)

    Schneider, Ivo

    The relationship between the astronomer von Zach on the one side and the entrepreneur Joseph von Utzschneider and his partner Georg von Reichenbach on the other dates presumably from the year 1807 when Zach spent two months in Munich. Already in the same year Zach had ordered an instrument for himself and began to solicit business for the institute of Reichenbach, Utzschneider, and Liebherr, which was founded in 1804. One of the clients canvassed by Zach was the director of the observatory in Naples Zuccari. Zuccari had ordered the whole equipment for the new observatory from this institute in 1813. The instruments for Naples, which were completed in 1814, were sent accompanied by Reichenbach by land and sea to their destination where Reichenbach supervised their setup. At that time Reichenbach had separated from Utzschneider who kept the optical institute in Benediktbeuern with his new partner Joseph von Fraunhofer whereas Reichenbach became owner of the mathematical-mechanical institute in Munich. For personal and economical reasons Utzschneider began soon after to produce not only optical glass but also optical devices similar to those offered by Reichenbach. As soon as two institutes in Munich competed against each other on the market for sophisticated geodetical and astronomical instruments Zach sided with Utzschneider. Zach's main professional argument for this decision was that both competitors got the optical glass for their instruments from Utzschneider's optical institute in Benediktbeuern. This meant that Utzschneider had first choice and so the optical part of his instruments could be considered as better than that of Reichenbach`s instruments. Zach's role as an agent in Italy and France for the sale of products coming from Utzschneider's manufactories is highlighted by three of Zach's letters to Utzschneider from 1817 and 1818, two of which are reproduced here for the first time.

  13. 3D-Druck von Kunststoff-Medizinprodukten

    OpenAIRE

    Polzin, Christian; Seitz, Hermann

    2012-01-01

    Das Additive Manufacturing gewinnt im Bereich der Medizintechnik zur Herstellung von Prototypen bis hin zu Endprodukten zunehmend an Bedeutung. Ein großes Hemmnis stellen allerdings die relativ hohen Fertigungskosten dar. Hier bietet der verstärkte Einsatz der 3D-Drucktechnologie (3D Printing) ein erhebliches Potential zur Reduktion der Kosten. Aus dieser Motivation heraus wurde ein 3D-Druckverfahren zur Herstellung biokompatibler, sterilisierbarer Kunststoffmodelle entwickelt. Beim 3D-Druck-...

  14. Semiparametric Bernstein–von Mises for the error standard deviation

    OpenAIRE

    Jonge, de, R.; Zanten, van, J.H.

    2013-01-01

    We study Bayes procedures for nonparametric regression problems with Gaussian errors, giving conditions under which a Bernstein–von Mises result holds for the marginal posterior distribution of the error standard deviation. We apply our general results to show that a single Bayes procedure using a hierarchical spline-based prior on the regression function and an independent prior on the error variance, can simultaneously achieve adaptive, rate-optimal estimation of a smooth, multivariate regr...

  15. 96 Über die Morphosyntaktische Struktur von Nominalkomposita im ...

    African Journals Online (AJOL)

    Die Yorùbá-Sprache, die von mehr als 25 Millionen Menschen allein in Nigeria gesprochen wird (vgl. Weisser 2008:1), ist die. Sprache der Yorùbá. Sie wird neben anderen Sprachen hauptsächlich in Südwest-Nigeria und z.T. in Benin, Togo,. Brasilien und Kuba gesprochen. Sie ist eine isolierende. Tonsprache, die zum ...

  16. Von Krahl klaarib piraadina asju euroliidus / Andres Laasik

    Index Scriptorium Estoniae

    Laasik, Andres, 1960-2016

    2006-01-01

    Von Krahli Teatri selle hooaja eelviimane esietendus "Europiraadid" on 17. mail Düsseldorfis, koostöös Saksamaa teatrirühmaga Showcase Beat Le Mot. (Varem on tehtud sama teatrirühmaga koostöös "Piraadid", mida mängiti nii Eestis kui Saksamaal). Eesti poole pealt teevad kaasa Juhan Ulfsak, Taavi Eelmaa, Maarja Jakobson ja Rain Tolk. Sakslaste poole pealt on tegijad Nikola Duric, Thorsten Eibler, Dariusz Kostyra ja Veit Spengler

  17. Eisengehalt von Fleisch - Ermittlung des Eisengehalts im Fleisch verschiedener Tierarten

    OpenAIRE

    Westphal, Karsten; Klose, Ralf; Golze, Manfred

    2009-01-01

    Der Bericht beinhaltet Ergebnisse von Fleischuntersuchungen auf den Eisengehalt. Untersucht wurden 308 Schweinefleischproben und etwa 300 Fleischproben der Tierarten Rind, Bison, Auerochse, Büffel, Schaf, Ziege, Kaninchen, Wildschwein, Rehwild, Rotwild und Fasan. Die sächsischen Ergebnisse bestätigen Untersuchungen anderer Bundesländer und belegen den starken Rückgang des Eisengehaltes im Schweinefleisch. Er lag im Mittel bei 4,1 mg/kg Frischmasse (FM). Vor 30 Jahren lag der Eisengehalt...

  18. Fibrolipoma en un paciente con la enfermedad de Von Recklinghausen

    Directory of Open Access Journals (Sweden)

    Orlando L Rodríguez Calzadilla

    2000-08-01

    Full Text Available Se presenta el caso de un paciente, con antecedente de padecer de la enfermedad de Von Recklinghausen, el cual fue valorado y su conducta terapéutica fue diferida, por sospechar la presencia de un tumor neurofibromatoso. El paciente se remitió a la consulta externa de nuestro servicio y una vez concluido sus estudios, se realizó su tratamiento quirúrgco. El paciente no presentó complicaciones transoperatorias y posoperatorias; su estadía fue de 3 días. Anatomía patológica informó la presencia de un fibrolipoma (neoplasia mesodérmica. El control a los 3 años de operado mostró un paciente asintomático y sin recidiva local. En la literatura médica revisada no se informaron otros casos similares de pacientes con la presencia de un fibrolipoma en la enfermedad de Von Recklinghausen.The case of a patient who suffers from Von Recklinghausen´s disease is reported. The patient was evaluated and his therapeutic conduct was deferred because the presence of a neurofibromatous tumor was suspected. The patient was referred to the outpatient department of our service and once the studies were concluded, he underwent surgical treatment. The patient had no transoperative or postoperative complications. He stayed in hospital only 3 days. The Department of Pathological Anatomy reported the presence of a fibrolipoma (mesodermic neoplasia. 3 years later the patient proved to be asymptomatic and without local relapse. Similar cases of patients with a fibrolipoma in Von Recklinghausen´s disease are not reported in the reviewed medical literature.

  19. Osteoporose bei Spondylitis ankylosans - Einfluß von Lebensgewohnheiten

    Directory of Open Access Journals (Sweden)

    Aglas F

    2004-01-01

    Full Text Available Krankheitsbedingte Artefakte können bei der SpA (Spondylitis ankylosans; Mb. Bechterew die Sensitivität einer Knochendichtemessung im Lumbalbereich beeinträchtigen. Das bei dieser rheumatischen Erkrankung bekannte Osteoporoserisiko ist neben genetischen Faktoren und Entzündungsmechanismen auch von verschiedenen exogenen Einflüssen abhängig. An 47 SpA-Patienten wurde mittels DEXA eine vergleichende Knochendichtemessung (BMD an der Hüfte (Schenkelhals und Ward'sches Dreieck sowie im Bereich der Wirbelsäule (L1-L4 vorgenommen. Zusätzlich erfolgte eine Erhebung der Lebens-Ernährungsgewohnheiten der SpA-Patienten in bezug auf die BMD, um exogene Einflüsse erfassen zu können. Die Knochendichtemessungen ergaben an der LWS wesentlich häufiger eine BMD im Normbereich als am proximalen Femur. Besonders deutliche Unterschiede traten im höheren Lebensalter auf, bei dem aufgrund von Kalzifizierungsvorgängen und Syndesmophyten an der LWS fälschlicherweise eine Dichtezunahme vorgetäuscht wird. Es kann daher bei SpA empfohlen werden, die wesentlich sensitivere Dichtemessung am Schenkelhals durchzuführen. Die über einen Zeitraum von 3 Jahren beobachteten, signifikant erhöhten, medianen CRP-Spiegel zeigen, daß eine permanente Aktivierung von Entzündungsprozessen bei SpA auch einen negativen Faktor betreffend des Knochenmasseverlustes darstellt. Die Analyse der Lebensgewohnheiten ergab, daß SpA-Patienten mit normaler BMD ausnahmslos regelmäßig kalziumreiche Nahrungsmittel zu sich nehmen; bei verminderter BMD wurde in der Mehrheit ein fehlender Konsum an Milchprodukten beobachtet. Leider war auch mit abnehmender BMD eine Verminderung der bei SpA empfohlenen Bewegungsübungen festzustellen. Aufgrund der Resultate ergibt sich eine generelle Empfehlung zu regelmäßigen Bewegungsübungen plus Osteoporosediät bei allen Bechterew-Patienten.

  20. Deutsche Literatur von Frauen – Jetzt auch digital!

    Directory of Open Access Journals (Sweden)

    Corinna Heipcke

    2002-07-01

    Full Text Available Die Digitale Bibliothek hat eine CD-Rom ediert, auf der ein Querschnitt durch die Werke von Autorinnen aus vier Jahrhunderten enthalten ist. Die Volltexte sind integriert in ein Bearbeitungsprogramm, das quellentreues Zitieren und Volltextrecherchen ermöglicht. Damit ist ein ausgesprochen praktisches Hilfsmittel für Germanistinnen und Germanisten entstanden. An ihre Grenzen gelangt die Sammlung allerdings bei der nicht unproblematischen Textauswahl.

  1. Gender-Dynamiken in der Rekonstruktion von Bildungsprozessen in Medienprojekten

    Directory of Open Access Journals (Sweden)

    Barbara Stauber

    2007-11-01

    Full Text Available Dieser Beitrag basiert auf Erfahrungen aus einem aktuellen Praxisforschungsprojekt des tifs (Tübinger Institut für frauenpolitische Sozialforschung. Es wurde in Auftrag gegeben von der Landesstiftung Baden-Württemberg zur Evaluation ihres Programms «Jugend und verantwortungsvolle Mediennutzung», mit dem sie medienpädagogische Projekte in unterschiedlichen Jugendhilfe-Kontexten (Projekte der offenen und der verbandlichen Jugendarbeit, der Hilfen zur Erziehung, der Jugendberatung etc. förderte.

  2. Sonographic findings in the Cruveilhier-von Baumgarten syndrome

    International Nuclear Information System (INIS)

    Pirschel, J.

    1982-01-01

    Portal hypertension is the most common complication of cirrhosis of the liver and leads to a reversal of blood flow and re-opening of pre-formed portal-systemic collaterals. Amongst a variety of possible hepato-fugal collaterals, the Cruveilhier-von Baumgarten syndrome, consisting of the reopening of umbilical veins, is a rare variant. It has been possible to demonstrate this clearly by sonography in 18 patients. (orig.) [de

  3. Decision Utility Theory: Back to von Neumann, Morgenstern, and Markowitz

    OpenAIRE

    Kontek, Krzysztof

    2010-01-01

    Prospect Theory (1979) and its Cumulative version (1992) argue for probability weighting to explain lottery choices. Decision Utility Theory presents an alternative solution, which makes no use of this concept. The new theory distinguishes decision and perception utility, postulates a double S-shaped decision utility curve similar to one hypothesized by Markowitz (1952), and applies the expected decision utility value similarly to the theory by von Neumann and Morgenstern (1944). Decision Uti...

  4. Interpolatability distinguishes LOCC from separable von Neumann measurements

    International Nuclear Information System (INIS)

    Childs, Andrew M.; Leung, Debbie; Mančinska, Laura; Ozols, Maris

    2013-01-01

    Local operations with classical communication (LOCC) and separable operations are two classes of quantum operations that play key roles in the study of quantum entanglement. Separable operations are strictly more powerful than LOCC, but no simple explanation of this phenomenon is known. We show that, in the case of von Neumann measurements, the ability to interpolate measurements is an operational principle that sets apart LOCC and separable operations

  5. Johann Baptist von Schweitzer: the queer Marx loved to hate.

    Science.gov (United States)

    Kennedy, H

    1995-01-01

    Despite his conviction on a morals charge involving a boy, the early German Social Democrat Johann Baptist von Schweitzer went on to have a successful political career. His life furnishes the context to present remarks by his political opponents Marx and Engels, which reveal their deep-seated homophobia. It is pointed out that this has been glossed over by the translations of the recently published Marx/Engels Collected Works. Some remarks on boy-love and anarchism are appended.

  6. Von Neuman representations on self-dual Hilbert W* moduli

    International Nuclear Information System (INIS)

    Frank, M.

    1987-01-01

    Von Neumann algebras M of bounded operators on self-dual Hilbert W* moduli H possessing a cyclic-separating element x-bar in H are considered. The close relation of them to certain real subspaces of H is established. Under the supposition that the underlying W*-algebra is commutative, a Tomita-Takesaki type theorem is stated. The natural cone in H arising from the pair (M, x-bar) is investigated and its properties are obtained

  7. Põlvkondade triloogia Von Krahli teatris / Hedi-Liis Toome

    Index Scriptorium Estoniae

    Toome, Hedi-Liis

    2010-01-01

    Von Krahli teatri lavastustest: William Shakespeare "Kuningas Lear", mängib Viljandi Kultuuriakadeemia 8. lend, lavastaja Peeter Jalakas (esietendus 30. jaan. 2010); "The End" - autorid, lavastajad ja näitlejad: Mari Abel, Tiina Tauraite, Riina Maidre, Erki Laur, Taavi Eelmaa, Juhan Ulfsak (esietendus 19. märts 2010); "Mehed lumes" Peter Freucheni jutustuse "Olavi lugu" ainetel lavastanud Mart Koldits ja Kristjan Sarv, kes ka ise mängivad (17. aprill 2010)

  8. Kundenorientierte Produktentwicklung mit Hilfe von Quality Function Deployment (QFD)

    OpenAIRE

    Schloske, Alexander

    2011-01-01

    Die Produktentwicklung von heute muss in immer kürzeren Zeiträumen kunden- und kostenorientierte Produkte entwickeln. Zur systematischen Unterstützung dieser Aufgabe im Rahmen der Produktentwicklung wird die Methode Quality Function Deployment (QFD) eingesetzt. Die konsequente Umsetzung der Stimme des Kunden in die Sprache des Unternehmens gelingt mit Quality Function Deployment (QFD). Die Methode wertet systematisch Kundenanforderungen an Produkte aus und führt zu innovativen Lösungen, die s...

  9. Ein Beitrag zur Erweiterung von Beamforming-Methoden

    OpenAIRE

    Kern, Marcus

    2008-01-01

    Im automobilen Entwicklungsprozess haben sich akustische Messsysteme etabliert, die mit einer Anordnung von Mikrofonen, einer optischen Kamera und einer nachgeschalteten Signalverarbeitung die Schalleinfallsrichtung detektieren und dadurch die Schalldruckverteilung auf Quellorte im Fernfeld zurückrechnen und visualisieren können. Die Signalverarbeitung beruht i. A. auf dem Delay&Sum-Beamforming, deren Umsetzung im Zeit- oder Frequenzbereich erfolgt. Die Schwächen dieser Messtechnik bezüglich ...

  10. Inkrementelles und oberflächenkompositionales Parsen von Koordinationsellipsen

    OpenAIRE

    Kapfer, Jörg

    2011-01-01

    Die Bezeichnung Koordinationsellipse wird in Ermangelung einer besseren Alternative verwendet, auch wenn sie der Zielsetzung widerspricht, eine Alternative zu Ansätzen aufzuzeigen, die im elliptischen Konjunkt weggelassene Elemente postulieren und diese soweit zu rekonstruieren versuchen, dass für sämtliche Konjunkte die gleiche Struktur angenommen werden kann. Das inkrementelle Parsen ist insofern für eine oberflächenkompositionale Analyse von Koordinationsellipsen unerlässlich, als die Stru...

  11. Practical event analysis; Durchfuehrung von Ereignisanalysen in der Praxis

    Energy Technology Data Exchange (ETDEWEB)

    Scheuring, R. [Bayernwerk Kernenergie GmbH - Kernkraftwerk Grafenrheinfeld (Germany)

    1999-04-01

    The paper explains the systematic approaches and practical aspects of evaluation of NPP operating reports and implementation of identified remedial action for enhancing the safety in terms of human, organisational, and technology factors. The procedures adopted for the Grafenrheinfeld nuclear power station (KKG) serve as an example. (orig./CB) [German] Ein wichtiger Bestandteil zur Erhaltung und Fortentwicklung des Sicherheitsniveaus ist das Lernen aus der Erfahrung. Hierzu wiederum ist ein systematisches Vorgehen zur Vermeidung von Fehlern und Behebung von Schwachstellen menschlicher, technischer und organisatorischer Natur unabdingbare Voraussetzung. Die Anwendung einer umfassenden Auswertemethodik beinhaltet - die Erfassung und Informationsweitergabe externer und interner Vorkommnisse und Erfahrungen - eine systematische Analyse/Auswertung - eine konsequente Umsetzung der Abhilfemassnahmen unter Einbeziehen aller betroffenen Organisationseinheiten. Wie erfolgt die Umsetzung dieser Vorgaben in die Praxis? Im Kernkraftwerk Grafenrheinfeld (KKG) ist die Auswertung von externen und internen Betriebserfahrungen als Aufgabe im Betriebshandbuch (BHB) 'Personelle Betriebsorganisation' vorgegeben und im Detail im Sinne der Ablauforganisation im Qualitaetssicherungshandbuch in Qualitaetssicherungsanweisungen (QSA) beschrieben. (orig.)

  12. Qualification of package units; Qualifizierung von Package Units

    Energy Technology Data Exchange (ETDEWEB)

    Brombacher, M.; Walter, U. [Bayer AG, Leverkusen (Germany)

    1999-07-01

    The use of package units in pharmaceutical plants is increasing. If they are involved in the manufacture of pharmaceuticals and have an influence on the quality of the end product, the user is required to validate the processes used. Parallel to the growing demands with respect to the automation of these units, the importance of PCS equipment has increased and with this the necessity for its qualification. Experience to date shows that the manufacturer's awareness of these requirements can be heightened still further. This paper describes approaches for improving the present situation and should be interpreted not as criticism but as providing an opportunity to increase the knowledge base and work together to define solutions which satisfy the guidelines. (orig.) [German] Der Einsatz von Package Units in Pharma-Anlagen erfaehrt zunehmende Verbreitung. Wenn sie an der Herstellung von Arzneimitteln beteiligt sind und auf die Qualitaet des Endprodukts Einfluss nehmen, unterliegen sie der Validierungspflicht, die der Anwender zu gewaehrleisten hat. Entsprechend den wachsenden Anforderungen an die Automatisierung dieser Einheiten ist auch der Stellenwert der PLT-Ausruestung angestiegen und mit ihm die Notwendigkeit von deren Qualifizierung. Die bisherige Praxis zeigt, dass die Sensbilitaet der Hersteller diesen Anforderungen gegenueber noch besser entwickelt werden kann. Der Beitrag zeigt Wege auf, um die derzeitige Situation zu verbessern und sollte nicht als Kritik sondern als Chance aufgefasst werden, den Wissensstand auszugleichen und gemeinsam zu richtliniengerechten Loesungen zu kommen. (orig.)

  13. Compliance with periodic surveillance for Von-Hippel-Lindau disease.

    Science.gov (United States)

    Lammens, Chantal R M; Aaronson, Neil K; Hes, Frederik J; Links, Thera P; Zonnenberg, Bernard A; Lenders, Jacques W M; Majoor-Krakauer, Danielle; Van Os, Theo A M; Gomez-Garcia, Encarna B; de Herder, Wouter; van der Luijt, Rob B; van den Ouweland, Ans M W; Van Hest, Liselot P; Verhoef, Senno; Bleiker, Eveline M A

    2011-06-01

    To assess compliance with a periodic surveillance regimen for Von Hippel-Lindau disease. In this nationwide study, Von Hippel-Lindau disease mutation carriers and those at 50% risk were invited to complete a questionnaire assessing (compliance with) advice given for periodic surveillance. Medical record data on compliance with recommended radiologic surveillance examinations were also collected. Of the 84 (77%) participants, 78 indicated having received advice to undergo periodic surveillance. Of these, 71 reported being fully compliant with that advice. In 64% of the cases, this advice was only partially consistent with published guidelines. Based on medical record data, between one quarter and one third of individuals did not undergo surveillance as recommended in the guidelines for central nervous system lesions and one half for visceral lesions. Screening delay for central nervous system lesions was significantly higher in one hospital and in those cases where "the advice given" deviated from the guidelines. The majority of those with or at risk of Von Hippel-Lindau disease reported having received and being fully compliant with screening advice. However, in many cases, the advice given was only partially consistent with published guidelines, and screening delays were observed. Efforts should be undertaken to stimulate guideline-based surveillance advice and to minimize screening delay.

  14. Prospektive, monozentrische, einarmige, randomisierte, kontrollierte Studie über fraktionierte CO₂-Lasertherapie von freien Hauttransplantaten

    OpenAIRE

    Schönberger, Carmen

    2017-01-01

    Hintergrund: Nach einer Hauttransplantation ist häufig das ästhetische Ergebnis aufgrund von Pigmentverschiebungen und Narben stark beeinträchtigt und wird von den Patienten als unbefriedigend betrachtet. Bisher gibt es keine prospektive, randomisierte, kontrollierte in vivo Studie, die die Wirksamkeit des fraktionierten CO2-Lasers zur Konturanpassung und Narbenkorrektur von Hauttransplantaten nachgewiesen hat. Da sich allerdings in der Vergangenheit in zahlreichen Studien der fraktionierte C...

  15. Ausbau der ganztägigen Kindertagesbetreuung kann zur Zufriedenheit von Müttern beitragen

    OpenAIRE

    Stahl, Juliane F.; Schober, Pia S.

    2016-01-01

    Eltern mit Kindern, die noch nicht zur Schule gehen, stehen bei der Vereinbarkeit von Familie und Beruf vor besonderen Herausforderungen. Um diese Eltern besser zu unterstützen, hat die Politik sowohl den Ausbau von Plätzen in der öffentlichen Kindertagesbetreuung (Kita) forciert als auch ein bedarfsorientiertes Angebot an Ganztagsplätzen gesetzlich verankert. Der vorliegende Beitrag untersucht auf Basis von Daten des Sozio-oekonomischen Panels (SOEP) und der Stichprobe 'Familien in Deutschla...

  16. Physikalische Grundlagen von chemischen Raman-Sensoren mit Schwerpunkt auf faseroptischen SERS-Sonden

    OpenAIRE

    Viets, Carmen

    2001-01-01

    Faseroptische SERS-Sensoren wurden durch die Beschichtung der Endflächen von optischen Fasern mit rauhen Metallfilmen erzeugt. Zu den verschiedenen Präparationstechniken, die angewendet und verglichen wurden, gehörten das langsame Aufdampfen von Metall-Inselfilmen und das Bedampfen von Nanopartikeln, aufgerauhten oder elektronenlithographisch strukturierten Oberflächen mit Metallfilmen. Der Einfluß der Laserleistung auf die Messungen mit SERS-Sensoren wurde untersucht, und es wurden maximale ...

  17. On the problem of completeness of QM: von Neumann against Einstein, Podolsky, and Rosen

    OpenAIRE

    Khrennikov, Andrei

    2008-01-01

    We performed a comparative analysis of the arguments of Einstein, Podolsky and Rosen -- EPR, 1935 (against the completeness of QM) and the theoretical formalism of QM (due to von Neumann, 1932). We found that the EPR considerations do not match at all with the von Neumann's theory. Thus EPR did not criticize the real theoretical model of QM. The root of EPR's paradoxical conclusion on incompleteness of QM is the misuse of von Neumann's projection postulate. EPR applied this postulate to obser...

  18. Gesamtfahrzeugsimulation betriebsfestigkeitsrelevanter Manöver unter Berücksichtigung von Fahrwerkregelsystemen

    OpenAIRE

    Brandes, Sebastian Jürgen

    2016-01-01

    In der Automobilbranche dient im Bereich der betriebsfesten Bemessung des Fahrwerks die Methode der Mehrkörpersysteme als Analyseverfahren zur Ermittlung von Bewegungen und Schnittgrößen an den Fahrwerksbauteilen. Eine der aktuellen Herausforderungen hierbei ist der zunehmende interdisziplinäre Charakter in Form von mechatronischen Fahrwerkssystemen. In rein virtuellen Entwicklungsphasen kann deren Einfluss auf die Fahrwerksbelastungen einzig anhand von Gesamtfahrzeugsimulationen ermittelt we...

  19. Molekulargenetische Studie zur Verbreitung und Interaktion von PCV-2 bei Haus- und Wildschweinen

    OpenAIRE

    Bronnert, Bastian Balthasar Marcel

    2014-01-01

    Im Rahmen der vorliegenden Arbeit wurden Wild- und Hausschweingewebeproben aus den Jahren 2005 bis 2008 mittels nested PCR auf das Vorkommen von PCV-2 untersucht und die positiv getesteten Proben mittels Realtime PCR quantifiziert. Zusätzlich wurden die Proben im Institut für Pathologie der Justus-Liebig-Universität histologisch und immunhistologisch untersucht (Dissertation Hohloch). Ziel war es das Vorkommen von PCV-2 und die Häufigkeit von PCV-2 assoziierter Erkankungen bei Haus- und Wilds...

  20. Analyse kognitiver Benutzermodelle für die Evaluation von Mensch-Maschine-Systemen

    OpenAIRE

    Dzaack, Jeronimo

    2008-01-01

    Die Entwicklung und Gestaltung von Schnittstellen für Mensch-Maschine-Systeme erfordern, neben der Kenntnis der Aufgabe und der Arbeitsumgebung, auch eine Vorstellung über die kognitiven Anforderungen an zukünftige Benutzer. Ein Grund dafür liegt in der zunehmenden Informationsdichte und dem ansteigenden Automatisierungsgrad von technischen Systemen. Daraus ergibt sich die Frage, welche Art von Schnittstelle die kognitiven Prozesse bei der Interaktion am besten unterstützt und wie diese prosp...

  1. Die Bedeutung internationaler Erfahrungen für den Karriereerfolg von Führungskräften

    OpenAIRE

    Biemann, Torsten

    2009-01-01

    Die langfristigen Auswirkungen internationaler Einsätze von Führungskräften auf deren Karrieren sind bislang kaum empirisch untersucht worden und die wenigen vorliegenden Ergebnisse sind widersprüchlich. Ziel dieser Studie ist deshalb die empirische Untersuchung der Auswirkungen internationaler Erfahrungen auf den Karriereerfolg von Führungskräften anhand eines Vergleichs von Führungskräften mit und ohne internationale Erfahrungen. Es zeigt sich, dass internationale Erfahrungen zu einem höher...

  2. Entwicklung von Cysteinproteaseinhibitoren - ein klassischer und ein kombinatorischer Ansatz zur Inhibitoroptimierung

    OpenAIRE

    Machon, Uwe Rainer

    2009-01-01

    Ziel der Dissertation „Entwicklung von Cysteinproteaseinhibitoren – ein klassischer und ein kombinatorischer Ansatz zur Inhibitoroptimierung“ war die Optimierung von neuen Inhibitoren von Falcipain-2 und Rhodesain als neue potentielle Wirkstoffe gegen Malaria bzw. die Schlafkrankheit über zwei verschiedene Methoden. Es handelt sich hierbei um einen klassischen und einen kombinatorischen Ansatz. Der klassische Ansatz basiert auf einer Struktur, deren Aktivität per Zufall entdeckt wurde. In Scr...

  3. Description of scattering material behaviour and damage in inelastic materials; Beschreibung von streuendem Materialverhalten und von Schaedigung bei inelastischen Werkstoffen

    Energy Technology Data Exchange (ETDEWEB)

    Pensky, H.M.H.

    2000-07-01

    For realistic numerical simulations of the stress-strain behaviour of structures, models are necessary which describe elastic-inelastic and scattering material behaviour. The developed models simulate elastic, viscoplastic and anisotropic damage material phenomena. An approach is proposed for covering stochastic material beahviour by correspondingly distributed parameters of the deterministic material model. Numerical simulations of biaxial material tests and structural tests demonstrate the range of applicability. (orig.) [German] Die realitaetsnahe numerische Simulation des Spannungs-Verformungsverhaltens von Bauteilen erfordert Modelle zur Beschreibung inelastischen und streuenden Materialverhaltens. Die hier entwickelten Modelle beschreiben elastische, viskoplastische und anisotrope Schaedigungsphaenomene des Materialverhaltens. Desweiteren wird ein Konzept vorgestellt, mit dem streuendes Materialverhalten mit streuenden Materialparametersaetzen deterministischer Stoffmodelle beschreibbar ist. Numerische Simulationen von Werkstoff- und Bauteilversuchen veranschaulichen den Anwendungsbereich der Modelle. (orig.)

  4. Christian Enichlmayr, Leiter der Oberösterreichischen Landesbibliothek von 1999 bis 2015, beantwortet 10 Fragen von Bruno Bauer

    Directory of Open Access Journals (Sweden)

    Christian Enichlmayr

    2016-05-01

    Full Text Available Christian Enichlmayr beantwortet Fragen über seinen Start ins Berufsleben in der Verlagsbranche, seine Zeit an der Universitätsbibliothek Linz und seinen Wechsel an die Oberösterreichische Landesbibliothek. 1999 bis 2015 war er als deren Leiter auch in führender Position für die Transformation der Bundesstaatlichen Studienbibliothek zur Landesbibliothek sowie die Sanierung und Erweiterung des Bibliotheksgebäudes verantwortlich. Weitere Themen, die in den vergangenen 17 Jahren an der Landesbibliothek stark forciert wurden, erstrecken sich von der NS-Provenienzforschung über die Entwicklung der digitalen Landesbibliothek bis zur Stärkung der Rolle der Landesbibliothek im oberösterreichischen Kulturleben. Zuletzt spricht Enichlmayr über die Bedeutung von Kooperationen im Bibliothekswesen, die Ausrichtung des Bibliothekartages der Vereinigung Österreichischer Bibliothekarinnen und Bibliothekare 2004 in Linz sowie die Perspektive für Bibliotheken.

  5. August von Kotzebue estofiilina / Otto-Heinrich Elias ; saksa keelest tõlkinud Reet Bender

    Index Scriptorium Estoniae

    Elias, Otto-Heinrich, 1932-

    2011-01-01

    Tutvustatakse August von Kotzebue kirjanduslikku - ja draamaloomingut, tema rolli seadusreformide mõjutamisel ning eestlastest positiivse kujundi loomisel. Peatutakse ka tema reisil revolutsioonilisel Prantsusmaal

  6. Mesostrukturierung und chemische Modifikation von Kathodenmaterialien zur Anwendung in Lithium-Schwefel Batterien

    OpenAIRE

    Schneider, Artur

    2016-01-01

    Die vorliegende Dissertation beschäftigt sich mit der Strukturierung und Charakterisierung von Kohlenstoffmaterialien, ihrer chemischen Modifikation, sowie deren Einsatz als Kathodenmaterialien in Lithium-Schwefel Batterien.

  7. Ungleiche Ungleichheiten:Zu den Gemeinsamkeiten und Unterschieden von Sexismus und Rassismus

    OpenAIRE

    Späte, K. (Katrin)

    2011-01-01

    Sexismus durchzieht fast alle gesellschaftlichen Teilbereiche und deren Grundlagen, im Kern ging es schon Jahrtausende lang um die Rechtfertigung der Herrschaft von Männern über Frauen. Die Minderwertigkeit „der Frau“ wurde unter Rückgriff auf natürliche Begebenheiten bewiesen. Die Grundlage sowohl von Sexismus als auch von Rassismus ist eine Konstruktion: Beim Sexismus die des „weiblichen Geschlechts“, beim Rassismus die der „Rasse“. Während sich die Benennung des Objekts von Rassismus im...

  8. Einflüsse von Computer- und Mediennutzung auf die Persönlichkeitsentwicklung von Kindern und Jugendlichen

    OpenAIRE

    Süss, Daniel

    2007-01-01

    Kinder und Jugendliche entwickeln ihre Persönlichkeit in aktiver Auseinandersetzung mit Medien. Medienkompetenz ist zu einer Entwicklungsaufgabe geworden. Zugleich verändern die Medien die allgemeinen Sozialisationsprozesse wie die Integration in die Peergroup und die Ablösung von den Eltern. Medien können sowohl als Ressourcen wie auch als Risiken für die Entwicklung wirksam werden. Empirische Studien zeigen, dass Kinder einen immer reichhaltigeren Medienzugang haben und viel Zeit mit Bildsc...

  9. KRISENZUSTÄNDE UND ANWENDUNG VON ZWANGSMASSNAHMEN IN DER PSYCHIATRIE

    Directory of Open Access Journals (Sweden)

    Vesna Šendula Jengić

    2017-01-01

    Full Text Available In der Arbeit wird über die Phänomene der Aggressivität und Gewalt bei Menschen diskutiert, wobei man besonderen Wert auf die Personen mit seelischen Störungen legt. Krisenzustände und Gewaltverhalten gibt es nicht nur in der Psychiatrie. Es kann immer zu einem solchem Zustand und Verhalten kommen und jeder kann unter bestimmten Umständen sowohl Opfer als auch Täter sein. Multikausalität und Komplexität sowie auch individuelle Umstände und situationsbezogene Faktoren, welche zum Gewaltverhalten führen können, haben nur geringen Prognosekraft. Statistische Indikatoren andererseits können falsch positive und falsch negative Ergebnisse verbergen, wobei ein Fehler in der Einschätzung das Risiko zum Erscheinen eines Verhaltens drastisch erhöhen oder zum unrechtfertigten Entziehung der Freiheit führen kann. Zwangsmaβnahmen in der Psychiatrie sind nur ausnahmsweise anzuwenden, und zwar, wenn ein gefährliches Verhalten direkt das Leben und die Gesundheit einer Person oder einer Umgebung gefährdet. Darüber hinaus ist die Dauer von Zwangsmaβnahmen auch beschränkt. Die Gesetzesregulative, insbesondere das Gesetz über den Schutz von Personen mit seelischen Störungen (Amtsblatt der Republik Kroatien Nr. 76/2014 und die Ordnung über die Arten und die Weise der Anwendung von Zwangsmaβnahmen gegenüber den Personen mit schwierigen seelischen Störungen (Amtsblatt der Republik Kroatien Nr. 16/2015, dient als zusätzlicher Schutz der Rechte dieser Patientengruppe und schreibt die Arten und die Weise der Anwendung von Zwangsmaβnahmen sowie auch die Vorgehensweise. Zusätzliche Richtlinien und Vorgehensstrategien wurden auch von den Gesellschaften für Psychiatrie gegeben. In der Arbeit wird betont, dass bessere Bedingungen, Infrastruktur und Arbeitskräfte sowie auch ständige Entwicklung und Bewertung der Arbeitsqualität in der Psychiatrie erforderlich sind. Abschlieβend werden Standards und ethische Fragen in Betracht gezogen, wie

  10. Solar energy systems in modernized buildings; Solarenergienutzung bei der Sanierung von Gebaeuden

    Energy Technology Data Exchange (ETDEWEB)

    Voss, K. [Fraunhofer-Inst. fuer Solare Energiesysteme, Freiburg (Germany). Gruppe Solares Bauen

    1998-02-01

    The statistics of residential buildings in Germany is of extraordinary distinctness: About 70% of the houses are more than 25 years old and the construction rate is about 1% per annum. In most neighbouring European countries the situation is similar. Predictions show that almost 60% of the building stock of the year 2020 is already erected today. The conclusions: The present building stock is essential for the burden of the environment not only today but also tomorrow. Measures saving energy and protecting the climate must include the already existing houses. Solar concepts especially suited for the renovation of old housing should be more promoted. Technically mature products, architecturally and economically attractive and integrated concepts and convincing examples of practical applications are prerequisites for successful advances into this direction. (orig.) [Deutsch] Die statistische Analyse des Bestands an Wohngebaeuden in Deutschland spricht eine deutliche Sprache: Rund 70% der Gebaeude sind aelter als 25 Jahre; die Neubaurate liegt um 1% pro Jahr. In den meisten europaeischen Nachbarlaendern ist die Situation vergleichbar. Eine Hochrechnung auf das Jahr 2020 belegt, dass schon heute knapp 60% des dann vorliegenden Gebaeudebestands existieren. Fazit: Der Gebaeudebestand von heute bestimmt die Umweltbelastung von heute und morgen. Massnahmen zur Energieeinsparung und fuer einen wirkungsvollen Klimaschutz muessen vordringlich am Gebaeudebestand ansetzen. Unter dem Blickwinkel einer Verbreitung der Solartechnik ist offensichtlich, dass Solarkonzepten, die speziell an die Belange der Sanierung im Bestand angepasst sind, eine grosse Bedeutung zukommt. Voraussetzungen fuer einen erfolgreichen Weg in diesen Markt sind technisch ausgereifte Produkte, architektonisch und wirtschaftlich attraktive Gesamtkonzepte sowie ueberzeugende Beispiele aus der Praxis. (orig.)

  11. Interpretation of ultrasonic images; Interpretation von Ultraschall-Abbildungen

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, W; Schmitz, V; Kroening, M [Fraunhofer-Institut fuer Zerstoerungsfreie Pruefverfahren, Saarbruecken (Germany)

    1998-11-01

    During the evaluation of ultrasonic images, e.g. SAFT-reconstructed B-scan images (SAFT=Synthetic Aperture Focusing Technique) it is often difficult to decide, what is the origin of reconstructed image points: were they caused by defects, specimens geometry or mode-conversions. To facilitate this evaluation a tool based on the comparison of data was developed. Different kinds of data comparison are possible: identification of that RF-signals, which caused the reconstructed image point. This is the comparison of a reconstructed image with the corresponding RF-data. Comparison of two reconstructed images performing a superposition using logical operators. In this case e.g. the reconstruction of an unknown reflector is compared with that of a known one. Comparison of raw-RF-data by simultaneous scanning through two data sets. Here the echoes of an unknown reflector are compared with the echoes of a known one. The necessary datasets of known reflectors may be generated experimentally on reference reflectors or modelled. The aim is the identification of the reflector type, e.g. cracklike or not, the determination of position, size and orientation as well as the identification of accompanying satellite echoes. The interpretation of the SAFT-reconstructed B-scan image is carried out by a complete description of the reflector. In addition to the aim of interpretation the tool described is well suited to educate and train ultrasonic testers. (orig./MM) [Deutsch] Bei der Auswertung von Ultraschall-Abbildungen, z.B. SAFT-rekonstruierten B-Bildern (SAFT=Synthetische Apertur Fokus Technik), ist es oft schwierig zu entscheiden, wo rekonstruierte Bildpunkte herruehren: wurden sie durch Materialfehler, Bauteilgeometrie oder durch Wellenumwandlungen versursacht. Um diese Auswertung zu erleichtern, wurde ein Werkzeug entwickelt, welches auf dem Vergleich von Datensaetzen basiert. Es koennen verschiedene Arten des Datenvergleichs durchgefuehrt werden: Identifikation der HF

  12. Auftreten von Falschem Mehltau bei Gartenkresse (Lepidium sativum L. in der Saatgutvermehrung – Evaluierung von Saatgutbehandlung und Wachstumsbedingungen in einem Gefäßversuch

    Directory of Open Access Journals (Sweden)

    Zeller, Stefanie

    2014-09-01

    Full Text Available Die zur Familie der Brassicaceae gehörende Gartenkresse wird in Deutschland überwiegend im biologischen Anbau vermehrt. Seit einigen Jahren werden diese Gartenkressebestände von Erregern des Falschen Mehltaus (Hyaloperonospora parasitica, Perofascia lepidii befallen, was zu einem Totalausfall des Pflanzenbestandes führen kann. Daher ist die biologische Saatgutproduktion von Gartenkresse gefährdet, was eine Beeinträchtigung der Saatgutversorgung für die Keimsprossenerzeugung zur Folge hat. In den laufenden Untersuchungen wird der Einfluss von nicht chemischen Saatgutbehandlungsmaßnahmen (Wasserdampf, Elektronen, sowie Wachstumsbedingungen (Feuchte, Boden auf die Infektion mit Falschem Mehltau untersucht.

  13. The need for company information manuals - Benefits of industry-wide standard solutions; Notwendigkeit von Betriebshandbuechern - Vorteile von Branchen-Standardloesungen

    Energy Technology Data Exchange (ETDEWEB)

    Sporleder, R.; Winter, G. [Stadtwerke Rostock AG (Germany)

    2000-07-01

    The paper explains the need for and the usefulness of company information manuals for companies of the energy sector. (orig./CB) [German] Im folgenden wird anhand von Kernsaetzen die Notwendigkeit von Betriebshandbuechern begruendet. Es wird offensichtlich, dass Geschaeftsfuehrungen von sicherheitsrelevanten Unternehmen wohlberaten sind, die in verschiedenen Vorschriften geforderte betriebliche Umsetzung des Inhalts dieser Vorschriften auf die firmeninternen Organisationsstrukturen vorzunehmen. Diese Umsetzung hilft intern, die betrieblichen Verantwortlichkeiten festzulegen, Verfahrensablaeufe zu bestimmen und erhoeht im Schadensfall erheblich die Chance fuer die jeweilige Geschaeftsfuehrung, den strafrechtlichen Vorwurf des Organisationsverschuldens abzuwehren. (orig./CB)

  14. Ueber den begriff "Kinoplasma" in der spermiogenese von Australorbis Glabratus Olivaceus (Mollusca, Pulmonata, Planorbidae

    Directory of Open Access Journals (Sweden)

    Rudolf Barth

    1960-11-01

    Full Text Available Zur Klaerung der Frage, ob der Begriff "Kinoplasma" fuer gewisse, von MERTON (1924,1926, 1930 beobachtete Bildungen an den reifenden Spermiden von pulmonaten Mollusken oder fuer Bestandteile des Cytoplasmas im Sinne von STRASBURGER und SCARTH zu verwenden ist, werden in der vorliegenden Mitteilung die Vorgaenge bei der Spermiohistogenese von Australorbis glabratus olivaceus untersucht. Es ergibt sich: 1. Das von MERTON bezeichnete "Kinoplasma" existiert nicht als solches, es handelt sich bei den von ihm dargestellten Protoplasmabildungen um kugelige, von den Spermiden abgeschnuerte Restkoerper nicht verwendeten Baumaterials, bestehend aus Protoplasma und einigen Mitochondrien. Sie werden von den Naehr- oder Bazalzellen phagozytiert. Der Ausdruck "Kinoplasma" kann nur fuer die submikroskopischen, geformten, faedigen Elemente des Cytoplasmas reserviert bleiben, die den geradlinigen Fall der uebrigen nicht geformten Komponenten bremst oder ablenkt; damit muss das Kinoplasma aber aus dem Begriff des Cytoplasmas herausgenommen werden, da es, wenn auch vermutlich reversibel, eine Differenzierung darstellt. 2. Der Spermienfaden wird von den Centriolen (Axialfilament und den Mitochondrien (zwei peripher gelegene Spiralfilamente, sowie einem Plasmamantel gebildet. 3. Nach Beendigung des Auswachsens der Spermiengeissel, die zu diesem Zeitpunkt nur aus dem Achsenfaden und dem Protoplasmazylinder besteht, setzt sich eine Protoplasmamasse vom Kopf in Richtung zum Geisselende in Bewegung. Sie fuehrt den Golgi-Koerper und sehr viele Mitochondrien mit sich. Aus diesen entwickeln sich Fibrillen, die sich zu den beiden Spiralfilamenten zusammenfuegen. Diese Masse entspricht der von MERTON in seiner Theorie als Kinoplasma bezeichneten Komponente. 4. Die Bewegung dieses Protoplasmateils wird auf den Schub zurueckgefuehrt, den die sich bildenden Fibrillen auf die Mitochondrien ausueben. 5. Die Rueckwaertsbewegung dieses Protoplasmakoerpers beruht wahrscheinlich auf

  15. [Von den Restgütern zu den Sowchosen in Estland 1939-1953. Dokumentensammlung] / Olev Liivik

    Index Scriptorium Estoniae

    Liivik, Olev, 1975-

    2011-01-01

    Arvustus: Von den Restgütern zu den Sowchosen in Estland 1939-1953 : Dokumentensammlung / Hrsg. von David Feest, Karsten Brüggemann. Berlin : Lit Verlag, 2010. (Schriften der Baltischen historischen Kommission ; Bd. 15)

  16. Kolonel Arthur von Buxhoevedeni (VR 1/2) ja tema abikaasa Kira ümbermatmine kodumaa mulda / Peep Pillak

    Index Scriptorium Estoniae

    Pillak, Peep, 1957-

    2015-01-01

    Vabadusristi kavaler kolonel Arthur von Buxhoeveden ja tema abikaasa Kira sängitati sõjaväeliste austusavaldustega kodumaa mulda Tallinna Kaitseväe kalmistul 12. septembril. Kolonel Arthur von Buxhoeveden'i elukäigust

  17. Mädchenschule und Geschlecht: Eine fallrekonstruktive Untersuchung der kollektiven Orientierungen und Weiblichkeitskonstruktionen von Schülerinnen monoedukativer Schulen

    OpenAIRE

    Waburg, Wiebke

    2010-01-01

    Die Dissertation ist im Rahmen des Projektes "Schulkultur, Geschlechtersegregation und Mädchensozialisation – DIAM" (Projektleitung L. Herwartz-Emden; gefördert von der DFG) entstandenen. In der Arbeit erfolgt die Rekonstruktion der Geschlechtskonstruktionen von Schülerinnen aus Mädchenschulen. Untersucht werden die kollektiven (geschlechtsbezogenen) Orientierungen von Mädchen und jungen Frauen im Alter von 13-19 Jahren. Die Schülerinnen befinden sich in der kulturell definierten Altersphase ...

  18. Zur Makrostruktur von Finanzmärkten: Börsen als Finanzintermediäre im Wettbewerb

    OpenAIRE

    Oehler, Andreas

    2003-01-01

    Die Analyse der so genannten Mikrostruktur von Finanzmärkten und ihr Einfluss auf das Marktergebnis haben in den letzten Jahren im Fokus der Finanzmarktforschung gestanden. Hinsichtlich der Entwicklung, Gestaltung und Regulierung von Finanzsystemen ist jedoch eine Erweiterung des Blickfeldes gewissermaßen in der Gegenrichtung ebenfalls zu forcieren, also die theoretische wie empirische Analyse der Makrostruktur von Finanzmärkten, die insbesondere Wettbewerb und Fragmentierung von Finanzmärkte...

  19. Biotechnologische Konversion von Nebenströmen der Lebensmittelindustrie zu hochwertigen Aromastoffen durch Basidiomyceten

    OpenAIRE

    Kunkel, Katrin

    2013-01-01

    29 Basidiomyceten wurden hinsichtlich der Bildung von natürlichen Aromastoffgemischen in Substrat-supplementierten Submerskulturen untersucht. Als Substrate dienten Karottenschalen, Blattspinat, Sellerietrester, Zwiebelschalen, Lauchtrester und Zitruspellets, die als Reststoffe in der lebensmittelverarbeitenden Industrie anfallen. Die Geruchseindrücke von 61 Biotransformationen wurden im Vergleich zu den Substrat- und Pilz-Blindwerten beurteilt und die Reproduzierbarkeit der ansprechendsten B...

  20. Pärnu-Jaagupi Jakobi kirik / Rudolf Moritz von Engelhardt, Elert Thiele, Ants Laikmaa...[jt.

    Index Scriptorium Estoniae

    2007-01-01

    välisvaade, sisevaade; olulised juurdeehitustööd 1695, uus läänetorn 1888, tornikiiver 1907 (arhitekt Rudolf von Engelhart), barokiaegne kantsel (Elert Thiele, u. 1660), varaklassitsistlik altarisein (1793), altarimaal "Kristus ristil" (Ants Laikmaa Eduard von Gebhardti järgi, 1901)

  1. Nonconventional ergodic averages and multiple recurrence for von Neumann dynamical systems

    NARCIS (Netherlands)

    Austin, T.; Eisner, T.; Tao, T.

    2011-01-01

    The Furstenberg recurrence theorem (or equivalently Szemerédi’s theorem) can be formulated in the language of von Neumann algebras as follows: given an integer k ≥ 2, an abelian finite von Neumann algebra (M,τ) with an automorphism α : M→M, and a nonnegative a in M with τ(a) > 0, one has liminf

  2. Von Krahli teater kolib mõneks ajaks Saksamaale / Rain Tolk

    Index Scriptorium Estoniae

    Tolk, Rain, 1977-

    2006-01-01

    Von Krahli Teatri selle hooaja eelviimane esietendus "Europiraadid" on 17. mail Düsseldorfis, koostöös Saksamaa teatrirühmaga Showcase Beat Le Mot. Eesti poole pealt teevad kaasa Juhan Ulfsak, Taavi Eelmaa, Maarja Jakobson ja üllatusmängijana filmimees Rain Tolk, kes räägib oma suhtumisest teatrisse ja suhetest Von Krahli Teatriga

  3. Number-conserving cellular automata with a von Neumann neighborhood of range one

    International Nuclear Information System (INIS)

    Wolnik, Barbara; Dzedzej, Adam; Baetens, Jan M; De Baets, Bernard

    2017-01-01

    We present necessary and sufficient conditions for a cellular automaton with a von Neumann neighborhood of range one to be number-conserving. The conditions are formulated for any dimension and for any set of states containing zero. The use of the geometric structure of the von Neumann neighborhood allows for computationally tractable conditions even in higher dimensions. (paper)

  4. Heinrich von Wlislocki in the memories of his contemporaries

    Directory of Open Access Journals (Sweden)

    Svetlana Procop

    2017-12-01

    Full Text Available The article presents Heinrich von Wlislocki – a folklorist, literary historian, linguist and educator, wide ly known in the scientific circles of Europe of the late XIX century, as one of the first XIX century European researcher of the gypsies – in the memories of his contemporaries. He was a Doctor of Philosophy, one of those whom his colleagues called a “friend of the Gypsies”, he went to wander with the camp of Transylvanian gypsies to collect field material directly in their midst. As a result, about 80 papers were published in selected publications, as well as in well-known scientific journals in Europe. Most often, his publications could be seen in the Journal of the Gypsy Lore Society, of which he was a member. Being a contemporary of George Henry Borrow (1803–1881, Alexander Gheorghe Paspati (1814–1891, Charles Godfrey Leland (1824–1903, Francis Hindes Grum (1851–1902, Anton Herrmann (1851–1926, Hans Ferdinand Helmolt (1865–1929, Heinrich von Wlislocki (1856–1907 was one of the few folklorists and connoisseurs of Gypsy life and culture of the XIX century. The latter completely immersed themselves in the life of the Gypsy, mastering for the first time the ethnographic method of included observation. It was a heroic period of studying folklore in Europe, when dedicated scientists created a folkloric field of research from the scratch. 110 years passed since the death of Heinrich von Wlislocki but this did not erase his name from the historical memory, folklorist researchers still refer to his works, including them in scientific circulation.

  5. Effects of sorption agents on heavy metal release form incinerator slag; Laesst sich die Freisetzung von Schwermetallen aus MVA-Schlacken durch Zugabe von Sorbenten veraendern?

    Energy Technology Data Exchange (ETDEWEB)

    Heiser, U. [Johannes Gutenberg-Univ. Mainz, Mainz (Germany); Kersten, M. [Johannes Gutenberg-Univ. Mainz, Mainz (Germany). Inst. fuer Geowissenschaften

    2003-11-01

    It was investigated inhowfar additions of sorption agents will influence the solution of heavy metals in incinerator slag. [German] Es wurde untersucht, ob nicht durch Zugabe bestimmter Stoffe zur Muellschlacke die Loesung von Schwermetallen beschleunigt werden kann. (orig.)

  6. Von Systemkritik zur Anpassung : Wie ein Buch in der Übersetzung die Farbe wechselt / Marianne Vogel

    Index Scriptorium Estoniae

    Vogel, Marianne

    2002-01-01

    Arvustus: Vetemaa, Enn. Die Nixen von Estland : ein Bestimmungsbuch / frei nach E. Vetemaa ; bearbeitet und illustriert von Kat Menschik ; nach dem russischen Übersetzungsmanuskript ins Deutsche übertragen von Günter Jäniche. Frankfurt/M : Eichborn Verlag, 2002.

  7. "Romeo ja Julia" Liivimaa moodi? Barbara von Tiesenhauseni legend : ajalooline tagapõhi ja kirjanduslikud variatsioonid / Juhan Kreem, Liina Lukas

    Index Scriptorium Estoniae

    Kreem, Juhan

    2008-01-01

    Käsitletakse järgnevaid ilukirjanduslikke teoseid: Fr. R. Kreutzwaldi ballaadi "Das Fräulein von Borkholm", Th. H. Panteniuse romaani "Die von Kelles" (e.k. "Kelleste omad. Romaan Liivimaa minevikust"), Marie Underi ballaadi "Porkuni preili", Aino Kallase novelli "Barbara von Tiesenhusen" ja Maimu Bergi romaani "Kirjutajad"

  8. Transpersonale Aspekte von Musik und Imagination in der Traumatherapie

    DEFF Research Database (Denmark)

    Maack, Carola

    2013-01-01

    Guided Imagery and Music nach Helen Bonny (GIM) und ihre Modifikationen haben sich in der Traumatherapie als sehr effektiv herausgestellt. In meinem Vortrag werde ich die Methode und ihre Anwendungen in der Traumatherapie vorstellen. Dabei gehe ich auch auf die Abgrenzung von Imagination im...... personalen und traunspersonalen Raum und deren jeweilige Bedeutung für traumatisierte Menschen in der unterschiedlichen Phasen ihrer Therapie ein. [The Bonny Methode of Guided Imagery and Music (GIM) and its modifications have shown to be quite effective in trauma therapy. In my presentation I will give...

  9. Otto von Guericke and 17th century cosmology

    Science.gov (United States)

    Knobloch, Eberhard

    Otto von Guericke's scientific method was based on reason and experimental science. His cosmology was embedded in theology and can be interpreted as a refutation of Descartes' worldview. He used Nicolaus Cusanus' theory of quantities in order to characterize space. The notion of space has to be distinguished from that of world or heaven. Forces play a crucial role in this respect described by Athanasius Kircher in his "Celestial Journey". Guericke read this work very diligently. In spite of some obvious similarities between Guericke's and Newton's scientific aims and methods there are crucial differences between the scientific convictions and results of these scholars.

  10. Digitale Transformation, aber wie? - Von der Spielwiese zur Umsetzungsplanung

    Science.gov (United States)

    Kaiser, Thomas

    Es besteht wohl kaum Anlass zur Annahme, dass die seit Jahrzehnten etablierten Markt- und Technologiestrukturen der Energiewirtschaft sich nicht in einem radikalen Ablöseprozess mit Gewinnern und Verlierern befinden. Aber Vorsicht - vordergründig bereits verloren erscheinende Geschäftsmodelle erfahren im Zuge der Digitalisierung einerseits noch intensiveren Wettbewerbsdruck, können aber andererseits von diesem "technologischen Jungbrunnen" profitieren, um verlorenes Terrain zurückzugewinnen. Im folgenden Kapitel wird ein Managementzyklus aufgezeigt, der in Anlehnung an die bereits erfolgreiche Implementierung digitaler R/Evolutionen anderer Branchen aufzeigt, wie die Geschäftsleitung systematisch kostenbewusst und zielorientiert die Digitalisierung umsetzen kann.

  11. Nachweis von Verticillium dahliae an Pfefferminze (Mentha x piperita L.

    Directory of Open Access Journals (Sweden)

    Gärber, Ute

    2014-09-01

    Full Text Available In Beständen von Pfefferminze wurden Krankheitssymptome beobachtet, die sich in Wuchshemmungen, Stängelverbräunungen, Blattchlorosen und Welke zeigten. Teilweise starben die Pflanzen bzw. einzelne Triebe ab. Als Ursache konnte Verticillium dahliae nachgewiesen werden. In einem Infektionsversuch im Gewächshaus wurden sieben Wochen alte Pfefferminzpflanzen der Sorte Multimentha durch Angießen mit einer Konidiensuspension (106 Konidien/ml Suspension inokuliert. Erste Krankheitssymptome erschienen acht Wochen nach Inokulation. Innerhalb kurzer Zeit nahm der Befall stark zu. Aus den kranken Pflanzenteilen wie Stängel und Blatt konnte der Erreger reisoliert werden.

  12. Inadequacy of von Neumann entropy for characterizing extractable work

    International Nuclear Information System (INIS)

    Dahlsten, Oscar C O; Renner, Renato; Rieper, Elisabeth; Vedral, Vlatko

    2011-01-01

    The lack of knowledge that an observer has about a system limits the amount of work it can extract. This lack of knowledge is normally quantified using the Gibbs/von Neumann entropy. We show that this standard approach is, surprisingly, only correct in very specific circumstances. In general, one should use the recently developed smooth entropy approach. For many common physical situations, including large but internally correlated systems, the resulting values for the extractable work can deviate arbitrarily from those suggested by the standard approach.

  13. Zum Bau und histologischen Terminologie von Laubmoosstämmchen

    OpenAIRE

    Frahm, Jan-Peter; Müller, Rolf-Dieter

    2012-01-01

    Es wird ein historischer Abriss der Geschichte der anatomischen Forschung an Moosen gegeben, der Aufbau von Laubmoosstämmchen skizziert und speziell die unterschiedliche Terminologie der Gewebetypen diskutiert. Der weit verbreitete Ausdruck Epidermis kann nicht auf Moose angewandt werden, weil die äußerste Schicht des Stämmchens nicht die Definiton des Begriffes erfüllt, verdickt und längsgestreckt ist. Sie gehört zur äußeren Sklerodermis. Längsgestreckt ist auch das sog. Parenchym oder Mark...

  14. Technische Feuchtgebiete zur Nachreinigung von Abwasser:Stickstoff, Abwasserdesinfektion, Spurenstoffe

    OpenAIRE

    Rühmland, Sabine

    2015-01-01

    Stickstoff, Spurenstoffe und Krankheitserreger können auch in geringen Mengen Schäden in Gewässern bzw. beim Menschen verursachen. In dieser Arbeit soll geklärt werden, inwieweit das naturnahe Abwasserreinigungsverfahren der technischen Feuchtgebiete zur Nachreinigung von Abwasser geeignet ist. Dafür wurden in Berlin sieben bewachsene Bodenfilter und Abwasserteiche im techni-schen Maßstab einer Kläranlage mit Nährstoffelimination nachgeschaltet. Ein Sandfilter, ein Sandfilter mit Lehm und...

  15. Anomalies free E-infinity from von Neumann's continuous geometry

    International Nuclear Information System (INIS)

    El Naschie, M.S.

    2008-01-01

    Von Neumann's continuous geometry has been considerably developed by Connes and is characterized by two fundamental concepts. First it is formulated without any direct reference to points and second it possesses a dimensional function. The present work explores the relevance of these two points to string theory as well as E-infinity theory. In particular we show that point-lessness and dimensional function implies fractality. In turn fractality leads to the concept of average or fuzzy symmetry and the elimination of gauge anomalies

  16. Funktionalisierung von Nanodiamanten für Wirkstofftransport und Knochenersatzmaterialien

    OpenAIRE

    Waag, Thilo

    2013-01-01

    Ziel der vorliegenden Arbeit ist das Design, die Synthese und das anschließende Testen von Nanodiamant-Wirkstoff-Konjugaten. Dafür müssen zunächst Nanodiamanten mit geeigneten Linkersystemen funktionalisiert werden, um anschließend verschiedene pharmazeutische Wirkstoffe auf der Diamantoberfläche zu immobilisieren. Die Wirksamkeit der so angebundenen Inhibitoren auf die verschiedenen Erreger muss anschließend in vitro und in vivo getestet werden. Auch die Art der Aufnahme der Nanodiaman...

  17. Ultraweak Continuity of σ-derivations on von Neumann Algebras

    International Nuclear Information System (INIS)

    Mirzavaziri, Madjid; Moslehian, Mohammad Sal

    2009-01-01

    Let σ be a surjective ultraweakly continuous *-linear mapping and d be a σ-derivation on a von Neumann algebra. We show that there are a surjective ultraweakly continuous *-homomorphism and a Σ-derivation such that D is ultraweakly continuous if and only if so is d. We use this fact to show that the σ-derivation d is automatically ultraweakly continuous. We also prove the converse in the sense that if σ is a linear mapping and d is an ultraweakly continuous *-σ-derivation, then there is an ultraweakly continuous linear mapping such that d is a *-Σ-derivation

  18. Bernstein - Von Mises theorem and its application in survival analysis

    Czech Academy of Sciences Publication Activity Database

    Timková, Jana

    2010-01-01

    Roč. 22, č. 3 (2010), s. 115-122 ISSN 1210-8022. [16. letní škola JČMF Robust 2010. Králíky, 30.01.2010-05.02.2010] R&D Projects: GA AV ČR(CZ) IAA101120604 Institutional research plan: CEZ:AV0Z10750506 Keywords : Cox model * bayesian asymptotics * survival function Subject RIV: BB - Applied Statistics, Operational Research http://library.utia.cas.cz/separaty/2010/SI/timkova-bernstein - von mises theorem and its application in survival analysis.pdf

  19. Von Blüten, Göttern und Gelehrten

    OpenAIRE

    Zotter, Astrid

    2013-01-01

    Der Sanskrittext Puṣpacintāmaṇi (PuCi) behandelt Blüten als Darbringungen (upacāra) im wichtigsten hinduistischen Verehrungsritual, der pūjā. In ca. 400 Strophen werden über 200 Namen von Blüten genannt und für verschiedene Gottheiten und pūjās als geeignete oder ungeeignete Gaben vorgeschrieben. Der Text ist eine Kompilation (Nibandha), in der die Inhalte aus 47 namentlich genannten Quellentexten referiert werden. Ziel der Dissertation ist es nicht nur, diesen Text, der 1966 zum ersten Ma...

  20. Content Management von Leittexten mit XML Topic Maps

    Directory of Open Access Journals (Sweden)

    Johannes Busse

    2003-07-01

    Full Text Available Die Autoren definieren den Umgang mit internet- basierten Informations- und Kommunikationstechnologien als Schlüsselqualifikation für Studierende aller Fachrichtungen. Im vorliegenden Aufsatz beschreiben sie ein Projekt, das der Fachbereich Erziehungswissenschaften der Universität Heidelberg seit 2001 durchführt. Hier werden Studierende der Geistes- und Sozialwissenschaften zu "Lernberatern" ausgebildet, die als Multiplikatoren die notwendigen Kenntnisse erwerben. Die Teilnehmenden erarbeiten nach der "Leittextmethode" selbstgesteuert xml-basierte Contents. Dies setzt den Erwerb von informationstechnischen Kenntnissen voraus, der neben dem Aufbau eines (sowohl technischen als auch sozialen Netzwerks einen Schwerpunkt bildet.