Motives for (not) participating in a lifestyle intervention trial

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Comparison and reproducibility of standard and high temporal resolution myocardial tissue tagging in patients with severe aortic stenosis

Objectives The aim of this study was to compare and assess the reproducibility of left ventricular (LV) circumferential peak systolic strain (PeakEcc) and strain rate (SR) measurements using standard and high temporal resolution myocardial tissue tagging in patients with severe aortic stenosis (AS). Background Myocardial tissue tagging with cardiac magnetic resonance (CMR) can be used to quantify strain and SR, however, there are little data on the reproducibility. Diastolic SR may be of particular interest as it may be the most sensitive marker of diastolic dysfunction often occurring early in the course of disease. Methods Eight patients with isolated severe AS without obstructive coronary artery disease were prospectively enrolled. They underwent CMR in a 1.5T scanner (Siemens Avanto) on two separate occasions, median interval 12 days. Complementary tagged (CSPAMM) images were acquired with both a single breath-hold (SBH: temporal resolution 42ms), and a multiple brief expiration breath-hold (MBH: high temporal resolution 17ms) sequence. Mid-wall PeakEcc was measured in the LV at mid-ventricular level with HARP Version 2.7 (Diagnosoft, USA). SR was calculated from the strain data; SR=Ecc2-Ecc1/Time2-Time1. PeakEcc , peak systolic and diastolic SR were read from curves of strain and SR against time. The MBH SR curves were filtered with a moving average (MA) to reduce noise sensitivity, results from a sample width of three and five were examined. Differences between SBH and MBH were assessed using Wilcoxon signed-rank test as not all measures were normally distributed. Reproducibility assessments were carried out on all techniques. Results PeakEcc was significantly higher with MBH vs. SBH, but reproducibility was slightly worse. Results are summarised in Table 1. Systolic SR was approximately equal with all techniques although MBH using MA of five led to a borderline significant reduction. Diastolic SR was higher when measured with MBH although only significant using MA of three. Systolic and diastolic SR measures were more reproducible with MBH compared with SBH, except for the diastolic SR using MA of three, which was substantially worse. Strain and SR curves for the same patient are shown in Figure 1

Разработка прожектора железнодорожного вокзала Томск-1

Основная задача наружного освещения на железных дорогах состоит в том, чтобы дать возможность персоналу и пассажиру определять: - пространственное расположение и состояние движения подвижного состава; - обеспечение беспрепятственного выполнения работы; - препятствия, мешающие безопасному движению; - железнодорожные сигналы; - безопасность работы персонала и нахождения пассажиров в зоне железной дороги. Железная дорога является зоной повышенной опасности, поэтому нет ничего удивительного, что железнодорожное освещение строго нормируется стандартами. Железнодорожные пути, станции и другие объекты нужно освещать на протяжении всей ночи, поэтому оборудование должно быть надежным и экономным.The main task of outdoor lighting on the railways is to enable the personnel and the passenger to determine: - Spatial location and state of movement of rolling stock; - ensuring unhindered performance of work; - obstacles to safe traffic; - railway signals; - safety of personnel and the presence of passengers in the railway zone. The railway is a zone of increased danger, so it is not surprising that railway lighting is strictly standardized by standards. Railway tracks, stations and other objects need to be illuminated throughout the night, so the equipment must be reliable and economical