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BackgroundThis study aimed to investigate the serial changes in left ventricular (LV) myocardial deformation in patients with sepsis using three-dimensional (3D) and two-dimensional (2D) speckle tracking echocardiography (STE).MethodsIn this single-center, prospective, and observational study, we included 59 patients diagnosed with sepsis or septic shock in the intensive care unit and 40 healthy controls. Left ventricular ejection fraction (LVEF), left ventricular global longitudinal strain (GLS), and global circumferential strain (GCS) assessed by 3D STE and 2D STE were obtained on the first, third, fifth, seventh to the tenth day after sepsis or septic shock.ResultsIn patients with sepsis or septic shock, 3D and 2D LVEF were not different at each time point. GLS and GCS obtained by 3D STE and 2D STE decreased on the first day compared with the healthy group (all P < 0.01). Compared with the values on the first day, GLS and GCS further decreased on the third day, while 3D and 2D LVEF did not differ. 3D and 2D STE strains were lowest on the third day and gradually improved on the seventh to the tenth day compared with values on the third day. When compared with values on the first day, 3D and 2D GLS gradually improved on the seventh to the tenth day, whereas 3D and 2D GCS on the seventh to the tenth day was not different. Although 3D and 2D STE strains were significantly increased on the seventh to the tenth day, they were not fully recovered to normality.ConclusionAlthough patients with sepsis or septic shock demonstrated gradual improvements in 3D and 2D STE parameters during the ten-day period, LV myocardial strain was not fully recovered to normality by the seventh to the tenth days. 3D and 2D strain imaging, used as a helpful tool for monitoring the evolution of myocardial deformation, can provide clinicians with a useful additional imaging parameter.

With the construction and future operation of the China Space Station (CSS), requirements of extensive preliminary ground experiments for projects onboard CSS, as well as those of scientific experiments utilizing ground-based short-term microgravity facilities, are increasing rapidly. A new microgravity experiment facility with electromagnetic launch is proposed and built by the Technology and Engineering Center for Space Utilization of Chinese Academy of Sciences. The design details of electromagnetic microgravity facility are introduced in this paper. This facility is mainly composed of double layered tower, linear induction motors, experimental capsule, energy storing device, high-power converters, electrical control system and electromagnetic release device. Then the microgravity level of the experimental payload achieved is evaluated through the analysis of kinematics and dynamics. The results of analysis indicate that the microgravity level of 10–5 g can be achieved for 4 s and optional gravity level from 10–5 g to 1 g can be created. With the drive concept, this facility will be capable of performing that the interval time between two experiments is less than 10 min. The acceleration and deceleration of experimental capsule can be controlled within 5 g through electromagnetic accelerating and electromagnetic braking. Physical verification and simulation tests are carried out on key technologies such as principle of electromagnetic launch, linear motor control, and electromagnetic release, which prove the effectiveness of the technical feasibility.

End effect of linear induction motor (LIM) brings asymmetry to the inductance matrix, leading to the imbalance of current and thrust ripples. In order to eliminate the current imbalance, inductance measurements and calculations are analyzed in this paper. The voltage strategy is designed through calculations of parameters of three-phase equivalent circuit and current results. The calculated results are validated by the experiments on a prototype of LIM.

Background: Previous studies showed that 2-dimensional speckle-tracking echocardiography (2D-STE) correlates with the extent of left ventricular(LV)myocardial fibrosis (MF). However, the utility of 3D-STE in predicting LV MF remains unknown. We aimed to identify which LV strain assessed by 2D- and 3D-STE is the most reliable parameter to predict LV MF in patients with end-stage HF. Methods: 105 patients with end-stage HF undergoing heart transplantation were enrolled in our study. LV global longitudinal strain (GLS), global circumferential strain (GCS) and global radial strain (GRS) were measured by 2D- and 3D-STE. LV ejection fraction (EF) was determined by 3D-STE.The degree of MF was quantified by using Masson trichrome stain in LV myocardial samples. The study population was divided into 3 groups according to the degree of MF on histology (mild, moderate, and severe MF). Results: Patients with severe MF had lower 2D-STE, 3D-STE, and LVEF compared with those with mild and moderate MF. LV MF strongly correlated with 3D-LVGLS (r =0.73; P < 0.001), modestly with 3D-LVGRS (r =0.53; P< 0.001), weakly with 2D-LVGLS (r =0.49, P Conclusion: 3D-LVGLS may be an ideal surrogate marker for LV MF in patients with end-stage HF.

The well-known GKYP is widely used in system analysis, but for singular systems, especially singular fractional order systems, there is no corresponding theory, for which many control problems for this type of system can not be optimized in the limited frequency ranges. In this paper, a universal framework of finite frequency band GKYP lemma for singular fractional order systems is established. Then the bounded real lemma in the sense of L is derived for different frequency ranges. Furthermore, the corresponding controller is designed to improve the L performance index of singular fractional order systems. Three illustrative examples are given to demonstrate the correctness and effectiveness of the theoretical results., 8 pages, 5 figures

Supplemental Digital Content is available in the text, We sought to evaluate the value of echocardiography in the diagnosis of different types of anomalous pulmonary venous connections (APVCs) and summarize the diagnostic experience. A total of 84 patients with APVC were confirmed by surgery (n = 82) or computerized tomography angiography (CTA) (n = 2) in the last 6 years (2008–2014) at the Wuhan Union Hospital. The total anomalous pulmonary venous connection (TAPVC) cases account for 60.7%, and partial anomalous pulmonary venous connection (PAPVC) cases account for 39.3% among the 84 cases that were identified. The 51 TAPVCs were classified by the Darling method—type I (41.1%), type II (52.9%), type III (1.9%), and type IV (3.9%). The most common drainage path of type I was common pulmonary drainage to the left innominate vein via vertical vein, and the coronary sinus drainage was the most common path in type II. Compared with surgical or CTA results, the sensitivity and specificity of echocardiography in the diagnosis of APVCs were 97.6% and 99.9%, respectively. The echocardiography misdiagnoses were mainly seen in PAPVCs. Of the TAPVCs and PAPVCs correctly diagnosed by echocardiography, the diagnostic accuracy of classification were 94% and 100%, respectively. Echocardiography has specific value in diagnosing and classification of APVC, especially the supracardiac and cardiac TAPVCs. Multiplane scan views and color Doppler improve the display of drainage pathway.

Objective The purpose of this study was to assess the impact of right ventricular (RV) myocardial histopathologic changes on ventricular function in patients with Tetralogy of Fallot (TOF). Methods Operatively resected crista supraventricularis muscle from 30 patients undergoing intracardiac repair of TOF were obtained for histopathologic evaluation. RV global longitudinal peak systolic strain (GLS), strain rate (GLSRs), early diastolic strain rate (GLSRe) and late diastolic strain rate (GLSRa) were measured by two-dimensional ultrasound speckle tracking imaging (STI) from the apical 4-chamber view. Results (1) Histopathologic data revealed hypertrophy of the cardiomyocytes, thickening endocardium, and increased interstitial and perivascular collagen in right ventricle in patients with TOF. (2) RV Cardiomyocyte diameter, interstitial collagen volume fraction (CVF) and endocardial thickness were correlated with age (r1=0.703, P1=0.000; r2=0.593, P2=0.001; r2=0.549, P2=0.002). (3) In patients with TOF, RV cardiomyocyte diameter and CVF had correlation with GLSRs (r1=−0.614, P1=0.000; r2=−0.517, P2=0.003). Endocardial thickness was correlated with GLS (r=−0.432, p=0.017). CVF corresponded with GLSRe (r=−0.669, p=0.000). (4) In patients with TOF, RV cardiomyocyte diameter was the independent predictor of RV GLSRs (β=−0.596, p=0.002), endocardial thickness and CVF were the independent predictor of RV GLS (β1=−0.918, P1=0.001, β2=−0.690, P2=0.008), CVF was the independent predictor of RV GLSRe (β=−0.618, p=0.001). Conclusions Myocardial tissues in patients with TOF indicates hypertrophic cardiomyocytes, thickening endocardium, and interstitial and perivascular fibrosis. These changes are more pronounced in older patients subjected to long-standing hypoxia and pressure overload. RV myocardial remodeling impacts inversely on ventricular systolic and diastolic function in patients with TOF.

Objective We sought to investigate the feasibility and reproducibility of the new semi-automated tool (4DLVQ) quantification of left ventricular (LV) volumes and ejection fraction (EF) compared to standard 3D echo tool (TomTec 4D LV-Analysis) using real time 3-dimensional echocardiography. Methods Real time 3D echocardiography examinations were performed in 24 volunteers. In the apical 3D full-volumetric images, LV end-diastolic volumes (EDV), end-systolic volumes (ESV) and EF were measured using 4DLVQ and TomTec. The repeatability and agreement of the new method were evaluated compared to TomTec. Results 1. The analysis time of 4DLVQ was significantly shorter than for TomTec (156.63±33.72 s vs 275.55±50.64 s, p 0.05). 3. LVEDV, LVESV and LVEF measured by 4DLVQ had good correlation with those by TomTec. (r 1 =0.715, r 2 =0.618 r 3 =0.532, respectively, p Conclusions 4DLVQ is a novel, simple, feasible and reproducible tool for LV volumes and EF.

Objective To initial explore the clinical feasibility, accuracy and reproducibility of evaluation of left ventricular (LV) volume and ejection fraction (EF) by 4-Dimensional Auto Left Ventrcular Quantification (4D AUTO LVQ) in three-dimensional echocardiography. Method Single heartbeat (SB) and multi-heartbeat (MB) mode three-dimensional echocardiography (3DE) examinations were performed in 20 volunteers, Left Ventricular end-diastolic volume (LVEDV), end-systolic volume (LVESV), and EF were measured by 4D AUTO LVQ. Meanwhile, LV volume and EF were also calculated by 2DE Simpson9s method and M-modeTeichholtz method. The measurement value of LV volume and EF by 4D AUTO LVQ in SB and MB mode was separately compared with every measurement value by other methods. Results 1. The values of LVEDV were statistically significant between M-mode method and other three methods (p Conclusions 4D AUTO LVQ in three-dimensional echocardiography gives accurate, rapid and reproducible measurements of LV volumes and EF.