Objectives This study sought to examine the relationships between right ventricular (RV) function, body composition, and prognosis in patients with advanced heart failure (HF). Background Previous ...studies investigating HF-related cachexia have not examined the impact of RV function on body composition. We hypothesized that RV dysfunction is linked to weight loss, abnormal body composition, and worsened prognosis in advanced HF. Methods Subjects with advanced HF (n = 408) underwent prospective assessment of body composition (skinfold thickness, dual-energy X-ray absorptiometry), comprehensive echocardiography, and blood testing. Subjects were followed up for adverse events (defined as death, transplantation, or circulatory assist device). Results Subjects with RV dysfunction (51%) had lower body mass index, lower fat mass index, and were more likely to display cachexia (19%). The extent of RV dysfunction correlated with greater antecedent weight loss and a lower fat/lean body mass ratio. Over a median follow-up of 541 days, there were 150 events (37%). Risk of event was greater in subjects with RV dysfunction (hazard ratio: 3.09 95% confidence interval (CI): 2.18 to 4.45) and cachexia (hazard ratio: 2.90 95% CI: 2.00 to 4.12) in univariate and multivariate analyses. Increased body mass index was associated with a lower event rate (HR per kg/m2 : 0.92 95% CI: 0.88 to 0.96), and this protection was mediated by a higher fat mass (0.91 95% CI: 0.87 to 0.96) but not a fat-free mass index (0.97 95% CI: 0.92 to 1.03). Conclusions RV dysfunction and cardiac cachexia often coexist, have additive adverse impact, and might be mechanistically interrelated. Wasting of fat but not of lean mass was predictive of adverse outcome, suggesting that fat loss is either a surrogate of enhanced catabolism or adipose tissue is cardioprotective in the context of HF.
The operating conditions of the production process significantly influence the resulting dimensional and form accuracy of the workpiece. The operating conditions include the position of the workpiece ...location, with internal and external heat sources influenced not only by the machine location but also by its operation. In addition, there are the cutting conditions and the feed rate requirements of CNC machine tools. These changes, such as workpiece position, feed rates, and machine heat load, are further reflected in the ability of the machine to run at the position required and interpolate within the given tolerances of circularity. For the accuracy and repeatability of positioning, the machine was set up according to ISO 230-2 and for the circular interpolation tests according to ISO 230-4. The obtained results show the importance of attention to the appropriate setting of the operating conditions of the production process, where the knowledge of the geometric accuracy of the CNC machine tool in its working space can systematically increase the manufacturing accuracy itself or be another tool suitable for predicting the dimensional and form accuracy of workpieces.
A 64-year-old woman with extensive tumorous infiltration of the mitral and aortic valves underwent partial resection of a tumor of the left ventricular outflow tract and replacement of both affected ...valves. Histology revealed an inflammatory pseudotumor with a significant number of immunoglobulin-G4-positive plasma cells. The histologic and clinical findings suggested immunoglobulin-G4-related disease of the heart.
This paper addresses the issue of transmission error (TE) evaluation. The motivation for writing this paper is the research on TE measurement and calculation, which focuses on finding a correlation ...between TE and the noise performance of spur gears. In the context of the study a research of an accurate description of the procedure for evaluating the TE waveform was carried out, but only incomplete descriptions were found. Therefore, the author tries to describe this problema according to the available sources and his own experience. The beginning of this article includes a description of what transmission error is and how it can be determined. The main part of this article, however, concerns developing a method for evaluating transmission error and introducing some new ideas on how to evaluate this magnitude more accurately.
This article concerns a study of the spur gear noise (i.e. sound pressure level) of automotive gearboxes. The aim is to verify a direct correlation between transmission error and noise emission of a ...gearing. The article includes a description of some gearbox noise sources and focuses on the gears itself, which is a main source of vibration and noise. A risk analysis is performed to assess the factors influencing gear noise, to show a significance of transmission error. The main part of this article, however, concerns experimentally identified transmission error and its correlation with measured noise.
We discuss two approaches to multilateration with a particular focus on numerical aspects for a given dataset. More precisely, we calculate the volumetric errors of the MCV 754 milling machine from ...the data measured by a LaserTRACER and provide criteria showing which numerical method is appropriate for the solution of the multilateration problem with respect to a given measurement dataset. In the first case, we consider two cost functions of the optimisation problem; in the second, we use the extremal principle method. We discuss the calculation accuracy depending on the matrix condition number. Our results are compared to the reference results produced by the Trac-Cal software, which is a standard used by most producers for error compensations.
The objective of this study was to compare long-term clinical effects of biventricular pacing with isolated left ventricular pacing.
Forty consecutive patients with idiopathic dilated cardiomyopathy ...and indication for cardiac resynchronization therapy were randomized to biventricular or isolated left ventricular pacing. Clinical and echocardiographic parameters were studied regularly prior to implantation and during 1 year of follow-up. Patients with atrial fibrillation were excluded from the study. A retrospective cross-sectional outcome analysis was performed 4 years after the beginning of the study. Biventricular pacing was associated with more pronounced clinical and echocardiographic benefit compared with left ventricular pacing. Biventricular pacing was associated with significantly more distinct reverse remodelling. Left ventricular ejection fraction improved by 12.5 per cent-points (95% CI 7.3-17.7) compared with 5.1 per cent-points (95% CI 1.1-9.2) (P = 0.01) and left ventricular end-diastolic diameter decreased by 8.69 mm (95% CI 5.2-12.2) compared with 5.1 mm (95% CI 1.5-8.7) (P = 0.05) in the biventricular and left-ventricular pacing group, respectively. Semi-quantitative summarization of response points revealed a greater benefit in the biventricular vs. left ventricular pacing group mean sum of response points 3.25 (95% CI 2.62-3.88) vs. 2.35 (95% CI 1.74-2.96), respectively, P = 0.06. After 3 years of follow-up, there was no cardiovascular death in the biventricular pacing group compared with three cardiovascular deaths in the left ventricular pacing group.
In patients with idiopathic dilated cardiomyopathy, biventricular pacing is associated with significantly more pronounced benefit in clinical outcomes and reverse remodelling. A retrospective analysis after 3 years of follow-up suggests that isolated left ventricular pacing may be associated with a higher mortality rate compared with biventricular pacing.
The article shows how the drive modelling depending on the required output information, focusing on the machine tool area. In this way, the simulation process can be optimally set up and the output ...information from the model environment can be used efficiently. From the selection of input parameters to the detail and accuracy of the output values of the model itself. Many authors are dealing with digital twins of production machines. However, they treat the actual drive part of the machine tool as a black box. However, its function occupies a significant part in the creation of such a model. On the other hand, the second part of the authors focus specifically on the actuator modeling, but they do not consider the methodological approach according to the need of output information. This is related to the negative impact on the impracticality of deploying such models in real applications.
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