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A practical high curvature path planning algorithm that considers the velocity limit of a mobile robot in joint space is proposed. The existence of obstacles that constrict the smooth movement of mobile robots is inevitable. To avoid incoming collision, the robot is redirected to a new path with respect to the dimensions of the obstacle and a safety factor. The redirected path consists of geometric constraints such as high curvatures on its turning points which cause difficulty in controlling the mobile robot. Thus, a central velocity generation method that considers both velocity limits through a convolution operator and high curvatures at turning points is suggested. The central velocity is able to be within the configured velocity limit, otherwise actual velocity commands in joint space could result. Therefore, interpolation to obtain uniform sampling and velocity downscaling is performed to generate a feasible joint space trajectory. The result shows short travelling time compared with previous methods while satisfying velocity limits in the joint space. [ABSTRACT FROM AUTHOR]

Background: We aimed to assess if quantitative radiomic features can predict programmed death ligand 1 (PD‐L1) expression in advanced stage lung adenocarcinoma. Methods: This retrospective study included 153 patients who had advanced stage (>IIIA by TNM classification) lung adenocarcinoma with pretreatment thin section computed tomography (CT) images and PD‐L1 expression test results in their pathology reports. Clinicopathological data were collected from electronic medical records. Visual analysis and radiomic feature extraction of the tumor from pretreatment CT were performed. We constructed two models for multivariate logistic regression analysis (one based on clinical variables, and the other based on a combination of clinical variables and radiomic features), and compared c‐statistics of the receiver operating characteristic curves of each model to identify the model with the higher predictability. Results: Among 153 patients, 53 patients were classified as PD‐L1 positive and 100 patients as PD‐L1 negative. There was no significant difference in clinical characteristics or imaging findings on visual analysis between the two groups (P > 0.05 for all). Rad‐score by radiomic analysis was higher in the PD‐L1 positive group than in the PD‐L1 negative group with a statistical significance (−0.378 ± 1.537 vs. −1.171 ± 0.822, P = 0.0008). A prediction model that uses clinical variables and CT radiomic features showed higher performance compared to a prediction model that uses clinical variables only (c‐statistic = 0.646 vs. 0.550, P = 0.0299). Conclusions: Quantitative CT radiomic features can predict PD‐L1 expression in advanced stage lung adenocarcinoma. A prediction model composed of clinical variables and CT radiomic features may facilitate noninvasive assessment of PD‐L1 expression. Key points: Significant findings of the study Quantitative CT radiomic features can help predict PD‐L1 expression, whereas none of the qualitative imaging findings is associated with PD‐L1 positivity. What this study adds A prediction model composed of clinical variables and CT radiomic features may facilitate noninvasive assessment of PD‐L1 expression. [ABSTRACT FROM AUTHOR]

Aims: Despite the prognostic importance of ventricular filling and ventricular-arterial interaction in patients with advanced systolic heart failure, the structural determinants of these parameters have not been fully studied. We aimed to investigate whether patterns of late gadolinium enhancement (LGE) on cardiac magnetic resonance affect ventricular elastic properties or performance in patients with non-ischaemic dilated cardiomyopathy (DCM). Methods and Results: Patients (n = 49) with markedly reduced systolic function (left ventricular (LV) ejection fraction <35%) due to longstanding non-ischaemic DCM underwent contrast-enhanced cardiac magnetic resonance after comprehensive echo-Doppler evaluations. The single beat-derived end-diastolic elastance, end-systolic elastance, arterial elastance, and dyssynchrony indices were measured by echo. On the basis of LGE patterns, patients could be divided into three groups: non-LGE (n = 18), non-midwall LGE (n = 13), and midwall LGE (n = 18). The midwall LGE group had lower LV systolic longitudinal velocity (4.6 +/- 1.7 for non-LGE vs. 4.3 +/- 1.2 for non-midwall LGE vs. 3.5 +/- 1.0 cm/s for midwall LGE, P = 0.025), higher end-diastolic elastance index (0.41 +/- 0.21 vs. 0.46 +/- 0.31 vs. 0.85 +/- 0.51 respectively, P = 0.008), and a more impaired ventriculoarterial coupling index (3.14 +/- 1.53 vs. 2.88 +/- 1.94 vs. 5.52 +/- 3.18, P = 0.006) than other subgroups. Conclusion: Patients with midwall LGE had a higher ventricular stiffness index and more impaired ventriculoarterial coupling when compared with other non-ischaemic DCM patients. [ABSTRACT FROM AUTHOR]