Objective- to determine the range of systolic times intervals using Pulsed-wave Doppler and m-mode echocardiography in normal, healthy Great Dane dogs. Design- Descriptive study. Animals- Thirty healthy Great Dane dogs. Procedures- This study examined 30 clinically healthy Great Dane dogs by the twodimensional, M-mode and Pulsed-wave Doppler echocardiography. The dogs were awake and unsedated. ...

As prior knowledge of Doppler frequency has been found useful in many applications of mobile communications, it is necessary to estimate the Doppler frequency at the mobile station (MS) based on the received fading signal. Rice et al 1] had derived Doppler frequency estimates using continuous-time received fading signals. In the present investigation, level crossing rate (LCR) and autocorrelati...

in this study, trans-pulmonic valvular gradient of 51 patients with congenital pulmonary stenosis measured by cw-doppler and cardiac catheterization were compared to find whether they are comparable and if doppler method is accurate enough for interventional decision-making. results showed that findings in both methods were comparable and doppler method is accurate and enough for clinical decis...

vertebrobasilar insufficiency is the cause of cerebrovascular accidents in 20% of cases. there are few reports regarding spectral doppler indices (sdis) of vertebral arteries (vas) normal blood flow. the objective of this study was to provide basic reference data about sdis of vas normal blood flow separately and in comparison with internal carotid arteries (icas) and common carotid arteries (c...

It is well established that light carrying orbital angular momentum (OAM) can be used to induce a mechanical torque causing an object to spin. We consider the complementary scenario: will an observer spinning relative to the beam axis measure a change in OAM as a result of their rotational velocity? Remarkably, although a linear Doppler shift changes the linear momentum of a photon, the angular...

-In order to better understand the relationship abnormalities, a systematic study of a11 factors that may affect between the power of the Doppler spectrum and blood flow the Doppler power is required. In this study, three important factors were investigated in pifro using a mock flow loop: a) the pulsation rate of the flow, b) the hematocrit of blood and c) the vessel wall compliance. The resul...

An experiment is described showing that a 33-GHz microwave signal received by rotating antennas is not exhibiting the frequency shift (“transverse Doppler effect”) predicted by the relativistic Doppler formula. The sensitivity of the apparatus used has been tested to be sufficient for detecting frequency shifts as small as 10 3 Hz which corresponds to the value of (v c) = 5 10 14 used in the tr...

One of the most important applications of Doppler ultrasonography in obstetrics is the detection of fetal anemia in pregnancies complicated by either red-cell alloimmunization or by other causes of fetal anemia. Doppler of the umbilical artery also has prognostic value in pregnancies affected by twin-twin transfusion syndrome undergoing in-utero intervention. Another potential major application...

      Background: Computed tomography scans (CT scan) and X-rays are used to diagnose paediatric maxillary sinusitis. This study aimed at exploring the diagnostic value of the conventional and colour Doppler ultrasounds and their specific findings in cases of paediatric sinusitis.    Methods: A total of 60 children diagnosed with sinusitis were included in this s...

Existing INS-aided GPS re-acquisition methods use either long coherent integration periods or non-coherent accumulation to obtain the required frequency resolution or acquire low C/N0 signals. Such methods need accurate position or velocity aiding, which is generally unavailable in many signal re-acquisition scenarios that use low-cost receiver oscillators and sensors. Furthermore, in high dyna...