Autonomous Navigation, Guidance and Control of Small Electric Helicopter

In this study, we design an autonomous navigation, guidance and control system for a small electric helicopter. Only small, light-weight, and inaccurate sensors can be used for the control of small helicopters because of the payload limitation. To overcome the problem of inaccurate sensors, a composite navigation system is designed. The designed navigation system enables us to precisely obtain the position and velocity of the helicopter. A guidance and control system is designed for stabilizing the helicopter at an arbitrary point in three-dimensional space. In particular, a novel and simple guidance system is designed using the combination of optimal control theory and quaternion kinematics. The designs of the study are validated experimentally, and the experimental results verify the efficiency of our navigation, guidance and control system for a small electric helicopter.ArticleINTERNATIONAL JOURNAL OF ADVANCED ROBOTIC SYSTEMS. 10:54 (2013)journal articl

Adenocarcinoma In Situ Arising from Brunner’s Gland Treated by Endoscopic Mucosal Resection

An 86-year-old Japanese man was presented to our hospital for further investigation of duodenal adenocarcinoma. The tumor was endoscopically resected. Pathological analysis revealed coexistence of gastric foveolar metaplasia and a surrounding hyperplastic Brunner’s gland, in addition to an adenocarcinoma component. Immunostaining for MUC5AC and MUC6 confirmed the diagnosis of adenocarcinoma in situ arising from Brunner’s gland hyperplasia. This case suggests that although detailed preoperative evaluation is required to determine the depth of tumor invasion, endoscopic resection may be a promising option for the treatment of adenocarcinomas arising from Brunner’s gland hyperplasia

Evaluation of image quality of pituitary dynamic contrast-enhanced MRI using time-resolved angiography with interleaved stochastic trajectories (TWIST) and iterative reconstruction TWIST (IT-TWIST)

Background: Time‐resolved angiography with interleaved stochastic trajectories (TWIST) is a keyhole imaging with frequent sampling of central k‐space data and view‐sharing for the peripheral k‐space of dynamic phases. IT‐TWIST is a technique to reconstruct images with a smaller temporal footprint using the same raw data obtained with TWIST by iterative reconstruction. Purpose: To compare image quality between TWIST and IT‐TWIST in 3D pituitary DCE‐MRI. Study Type: Retrospective observation study. Population: Fifty‐one patients (23 men, 28 women) who underwent 3D pituitary DCE‐MRI using TWIST between July 2016 and April 2017. Field Strength/Sequence: 3T/TWIST and IT‐TWIST. Assessment: Visual evaluation was conducted for image quality of delineation of the pituitary stalk and posterior lobe during the early arterial phase, cerebral white matter near the sella turcica, and the mass lesion. Bolus sharpness of the pituitary stalk, posterior lobe, and bilateral cavernous sinus was evaluated on the enhancement slope map calculated from TWIST and IT‐TWIST. Temporal stability of intensity of the nonenhanced area was evaluated on temporal standard deviation (SD) maps calculated from TWIST and IT‐TWIST. Statistical Tests: Paired t‐test or Wilcoxon rank‐sum test was used to test the differences between TWIST and IT‐TWIST in both visual evaluation and region of interest evaluation. Results: Scores of visual evaluations for IT‐TWIST were significantly better than those for TWIST (P < 0.001) in all items. Enhancement slope for IT‐TWIST was significantly higher than that for TWIST in posterior lobe, and right and left cavernous sinus (P < 0.001). Temporal SD for IT‐TWIST was significantly lower than that for TWIST in all items, with statistical significance (P < 0.001). Data Conclusion: IT‐TWIST yielded better visualization, and better enhancement slope, and less temporal SD compared with TWIST in 3D pituitary DCE‐MRI

Efficacy and safety of tezepelumab in patients recruited in Japan who participated in the phase 3 NAVIGATOR study

Background: Tezepelumab, a human monoclonal antibody, blocks the activity of thymic stromal lymphopoietin. In the phase 3 NAVIGATOR study (NCT03347279), tezepelumab reduced exacerbations by 56% compared with placebo in adults and adolescents with severe, uncontrolled asthma. This analysis evaluated the efficacy and safety of tezepelumab in NAVIGATOR patients recruited in Japan. Methods: NAVIGATOR was a phase 3, multicenter, randomized, double-blind, placebo-controlled study. Patients (12–80 years old) were randomized 1:1 to receive tezepelumab 210 mg or placebo subcutaneously every 4 weeks for 52 weeks. Endpoints assessed included: the annualized asthma exacerbation rate (AAER) over 52 weeks (primary endpoint) and the change from baseline to week 52 in pre-bronchodilator forced expiratory volume in 1 s (FEV1) and Asthma Control Questionnaire (ACQ)-6 score. The safety of tezepelumab was also assessed. Results: Overall, 97 patients recruited in Japan were randomized (tezepelumab, n = 58; placebo, n = 39). The AAER over 52 weeks was 1.54 (95% confidence interval [CI]: 0.90, 2.64) with tezepelumab compared with 3.12 (95% CI: 1.82, 5.35) with placebo (rate ratio: 0.49 [95% CI: 0.25, 0.99]; 51% reduction). For tezepelumab and placebo, the least-squares mean (standard error) change from baseline to week 52 for pre-bronchodilator FEV1 was 0.23 (0.06) L and 0.19 (0.07) L and the ACQ-6 score was −1.12 (0.15) and −0.97 (0.19), respectively. The frequency of adverse events was similar between treatment groups (tezepelumab, 86.2%; placebo, 87.2%). Conclusions: Tezepelumab reduced exacerbations compared with placebo, and was well tolerated, in NAVIGATOR patients with severe, uncontrolled asthma recruited in Japan