Sökning: "Impedance function"

Visar resultat 1 - 5 av 93 avhandlingar innehållade orden Impedance function.

  1. 1. Analysis of dipole antennas in the presence of conducting cylindrical structures

    Författare :Peter Slättman; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; moment method; cylinder; dipole; fourier transform; mutual impedance; self impedance; basis function; through waveguide; EFIE;

    Sammanfattning : .... LÄS MER

  3. 2. Strain echocardiography in cardiac surgery - studies on the effects of loading conditions and inotropic agents on myocardial contraction and relaxation

    Författare :Martin Fredholm; Göteborgs universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; strain echocardiography; right heart catheterization; cardiac surgery; heart failure; levosimendan; milrinone; left ventricular function; right ventricular function; systole; diastole; preload; afterload; pacing; longitudinal function; ventricular dimensions; ventricular interdependence;

    Sammanfattning : Background: Although reductions in myocardial contractility and relaxation are key compo-nents in heart failure (HF), assessment of them is difficult, as clinical measurements deal with a net effect of myocardial contractility, heart filling (preload), outflow impedance (afterload) and heart rate (HR). Echocardiographic (echo) deformation parameters, like strain (myocardial shortening) and strain rate (the speed of deformation, SR), have been proposed to more accu-rately measure myocardial function, but incongruent previous studies have raised concerns that they may be load-dependent. LÄS MER

  4. 3. Protamine, Platelet Function and Coagulation in Cardiac Surgery

    Författare :Mattias Törnudd; Sören Berg; John-Peder Escobar Kvitting; Sofia Ramström; Joakim Alfredsson; Ulf Schött; Linköpings universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Cardiopulmonary bypass; Protamine; Platelet function; Coagulation;

    Sammanfattning : Bleeding is a serious and common complication in cardiac surgery. Complicated surgery together with alterations in hemostatic conditions from the use of cardiopulmonary bypass (CPB), presents challenges in how to preserve hemostasis in the patient.   CPB is thought to affect platelet function and coagulation in many ways. LÄS MER

  5. 4. Ionic transport of α-alumina below 1000°C : an in-situ impedance spectrosocpy study

    Författare :Johan Öijerholm; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Materials science; α-alumina; in-situ impedance spectroscopy; molecular dynamics; spark plasma sintering; conductivity; microstructure; Materialvetenskap; Materials science; Teknisk materialvetenskap;

    Sammanfattning : Ionic conductivity of metal oxides is critical for the function of a broad range of different components, such as electrolytes in solid oxide fuel cells and alloys designed for high temperature applications. In both cases the ionic conductivity can be studied by in situ impedance spectroscopy, which is also able to reveal information on the dielectric properties of the metal oxides, and in some cases the influence of their microstructure. LÄS MER

  7. 5. Monitoring of coagulation and platelet function in paediatric cardiac surgery

    Författare :Birgitta S Romlin; Göteborgs universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; paediatric cardiac surgery; haemostasis; platelet; coagulation; thromboelastometry; impedance aggregometry; coagulopathy; haemoconcentration;

    Sammanfattning : Abstract Background: Paediatric cardiac surgery has developed dramatically during the last decades. Today, a wide range of patients is operated on-from premature neonates to grown up children with congenital heart disease. Excessive bleeding during and after cardiac surgery is still common, and it is one of the most serious complications. LÄS MER