Parallel Optical Method in Laser Speckle Velocimetry and Particle Image Velocimetry

A method of parallel optical processing of double exposure specklegram or particle image using hololens array is presented.It can greatly decrease the processing time because the mechanical moving time of the X Y translation stage is decreased by tens of times.     

Assessment of longitudinal systolic function using tissue motion annular displacement in healthy dogs

Introduction

Left ventricular systolic function is one of the main parameters studied in echocardiography. Longitudinal systolic function, however, is less commonly evaluated in routine examinations but may provide early information on systolic dysfunction. The movement of the mitral annulus toward the apex has already been determined as a method for evaluation of longitudinal systolic function in dogs, but the study of this movement by speckle tracking with the tissue motion annular displacement (TMAD) technique has not yet been evaluated.

数字散斑相关方法在木材指接中的应用

该文将数字散斑相关方法应用于指接木材的力学性能分析.首先编写了一种新的数字散斑相关计算程序,并通过数值模拟的方法验证其适合于拉伸实验;然后将它用于落叶松指接材的拉伸实验.结果表明,指接材在拉伸时齿根处发生了明显的应力集中现象,拉伸破坏首先从这里开始,另外齿长对落叶松指接材的抗拉强度影响较小;同时也证明了该方法用于木材指形接头的位移应变场分析是可行的.      

Speckle tracking echocardiography in mature Irish Wolfhound dogs: technical feasibility,measurement error and reference intervals

Background

Two-dimensional strain measurements obtained by speckle tracking echocardiography (STE) have been reported in both humans and dogs. Incorporation of this technique into canine clinical practice requires the availability of measurements from clinically normal dogs, ideally of the same breed, taken under normal clinical conditions.The aims of this prospective study were to assess if it is possible to obtain STE data during a routine echocardiographic examination in Irish Wolfhound dogs and that these data will provide reference values and an estimation of measurement error.

Methods

Fifty- four healthy mature Irish Wolfhounds were used. These were scanned under normal clinical conditions to obtain in one session both standard echocardiographic parameters and STE data. Measurement error was determined separately in 5 healthy mature Irish Wolfhounds.

Results

Eight dogs were rejected by the software algorithm for reasons of image quality, resulting in a total of 46 dogs (85.2%) being included in the statistical analysis. In 46 dogs it was possible to obtain STE data from three scanning planes, as well as to measure the rotation of the left ventricle at two levels and thus calculate the torsion of the heart. The mean peak radial strain at the cardiac apex (RS-apex) was 45.1 ± 10.4% (n = 44), and the mean peak radial strain at the base (RS-base) was 36.9 ± 14.7% (n = 46). The mean peak circumferential strain at the apex (CS-apex) was -24.8 ± 6.2% (n = 44), and the mean peak circumferential strain at the heart base (CS-base) was -15.9 ± 3.2% (n = 44). The mean peak longitudinal strain (LS) was -16.2 ± 3.0% (n = 46). The calculated mean peak torsion of the heart was 11.6 ± 5.1 degrees (n = 45).The measurement error was 24.8%, 26.4%, 11.5%, 6.7%, 9.0% and 10 degrees, for RS-apex, RS-base, CS-apex, CS-base, LS and torsion, respectively.

Conclusions

It is concluded that this technique can be included in a normal echocardiographic examination in large breed dogs under clinical conditions. The usefulness of the reference values reported here, given their wide normal range, will ultimately be determined by the values that are obtained from a large numbers of diseased dogs.     

Incremental predictive value of echocardiographic indices of right ventricular function in the assessment of long-term prognosis in dogs with myxomatous mitral valve disease

IntroductionFew studies have evaluated the utility of echocardiographic indices of right ventricular (RV) function in predicting prognosis in dogs with myxomatous mitral valve disease (MMVD).AnimalsSixty-seven client-owned dogs were diagnosed with MMVD.Materials and methodsclinical cohort study. Dogs diagnosed with American college of veterinary internal medicine (ACVIM) stage B2, C or D between April 2014 and March 2017 were enrolled. Long-term outcomes were assessed by telephone or from the medical record. The primary end-point was defined as cardiac-related death. Echocardiographic indices of RV function, including the RV Tei index, free wall and septal RV longitudinal strain, were obtained. Univariable and multivariable Cox proportional hazard analyses were used to identify variables predictive of cardiac-related death.ResultsTwenty-four dogs died during the follow-up period. The median follow-up time was 482 days, and the median survival time for dogs with cardiac-related death was 230 days. For cardiac-related death, peak early diastolic mitral inflow velocity, ACVIM stage C or D, tricuspid regurgitation velocity, RV Tei index and RV end-diastolic area were predictors in univariable Cox proportional hazard analysis. In multivariable Cox proportional analysis adjusted for the left atrial to aorta ratio, peak early diastolic mitral inflow velocity and ACVIM stage, an increase in the Tei index by 0.1 increased the hazard ratio of cardiac-related death by 33% (95% confidence interval, 16–70%; P = 0.002).ConclusionsIn dogs with MMVD, RV dysfunction assessed by the Tei index is an independent predictor of cardiac-related death.