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Reliable proprioception and feedback from soft sensors are crucial for enabling soft robots to function intelligently in real-world environments. Nevertheless, soft sensors are fragile and are susceptible to various damage sources in such environments. Some researchers have utilized redundant configuration, where healthy sensors compensate instantaneously for lost ones to maintain proprioception accuracy. However, achieving consistently reliable proprioception under diverse sensor degradation remains a challenge. This paper proposes a novel framework for graceful degradation in redundant soft sensor systems, incorporating a stochastic Long Short-Term Memory (LSTM) and a Time-Delay Feedforward Neural Network (TDFNN). The LSTM estimates readings from healthy sensors to compare them with actual data. Then, statistically abnormal readings are zeroed out. The TDFNN receives the processed sensor readings to perform proprioception. Simulation experiments with a musculoskeletal leg that contains 40 nonlinear soft sensors demonstrate the effectiveness of the proposed framework. Results show that the knee angle proprioception accuracy is retained across four distinct degradation scenarios. Notably, the mean proprioception error increases by less than 1.91°(1.36%) when 30 % of the sensors are degraded. These results suggest that the proposed framework enhances the reliability of soft sensor proprioception, thereby improving the robustness of soft robots in real-world applications. [ABSTRACT FROM AUTHOR]

Postoperative neurological deterioration due to brain compression by the swollen temporal muscle pedicle used in encephalo-myo-synangiosis (EMS) is a potential complication of combined revascularization for Moyamoya disease (MMD). However, the factors contributing to this phenomenon remain poorly understood. This study aimed to identify factors associated with postoperative temporal muscle swelling following combined revascularization. A total of 37 consecutive combined revascularization using temporal muscle pedicle performed between 2021 and 2023 were analyzed. Postoperative temporal muscle volume was measured through serial CT scans on postoperative days (POD) 0, 1, 7, 14, and 30. Multiple regression analysis was performed to assess factors contributing to swelling, including RNF213 p.R4810K variant, a known genetic risk for Asian MMD. Surgical outcomes and collateral vessel development were also examined. Results showed a significant increase in muscle pedicle volume on POD 1 and 7 across all 37 hemispheres, followed by a marked decrease by POD 30, compared to POD 0. These chronological volume changes were significant in adults (n = 31) but not in pediatric patients (n = 6). Multiple regression analysis identified the RNF213 p.R4810K as sole significant factor positively associated with maximal muscle volume (regression coefficient 0.485, P = 0.0078). Favorable surgical outcomes were achieved in 36 of 37 cases (97.3%) over a mean follow-up of 2.2 years, with indirect collateral development confirmed in 27 adult (87%) and 6 pediatric (100%) hemispheres. Results suggest the RNF213 p.R4810K variant is associated with increased postoperative temporal muscle swelling after combined revascularization, especially in adult MMD patients, indicating a potential genetic influence on this complication. [ABSTRACT FROM AUTHOR]

Background Sjögren's syndrome is a chronic autoimmune disorder that predominantly affects exocrine organs. It is characterized by an organ-specific infiltration of lymphocytes. The involvement of the major cerebral arteries in Sjögren's syndrome has rarely been reported. A recent study reported a case of successful extracranial–intracranial (EC–IC) bypass without complications, even in the active inflammatory state, although the optimal timing of such a bypass remains unclear. Case Description We here report the case of a 43-year-old woman presenting with acute ischemic stroke due to progressive middle cerebral artery (MCA) occlusion and signs of primary Sjögren's syndrome. During intensive immunosuppressive therapy for active Sjögren's syndrome, the patient was monitored using contrast-enhanced magnetic resonance vessel wall imaging (MR-VWI). A couple of intravenous cyclophosphamide injections combined with a methylprednisolone pulse and antiplatelet therapy resulted in clear resolution of vessel wall enhancement, which suggested remission of inflammatory vasculitis. Nevertheless, she still experienced a transient ischemic attack (TIA) due to decreased regional cerebral blood flow by MCA occlusion, as demonstrated by the conventional time-of-flight MR angiography and single-photon emission computed tomography. Considering the increased risk of further stroke, the decision was made to perform an EC–IC bypass as a treatment for medically uncontrollable hemodynamic impairment. Her postoperative course was uneventful without further repeated TIAs, and continued immunosuppressive therapy for Sjögren's syndrome provided effective management. Conclusions Our findings emphasize the diagnostic value of contrast-enhanced MR-VWI in monitoring the effect of immunosuppressive therapy for the major cerebral artery vasculitis and in determining the timing of EC–IC bypass as a "rescue" treatment for moyamoya syndrome associated with active Sjögren's syndrome. [ABSTRACT FROM AUTHOR]

Background Human immunodeficiency virus (HIV) associated vasculopathy can cause ischemic cerebral stroke; however, there is limited evidence on optimal management. Herein, we report a case of acute ischemic stroke due to progressive internal carotid artery (ICA) stenosis in an HIV-positive patient. Superficial temporal artery to middle cerebral artery (STA-MCA) bypass, in addition to the best medical treatments, prevented stroke progression. Clinical Description A 39-year-old man with HIV infection presented with a sudden onset of aphasia and right hemiparesis. Magnetic resonance imaging revealed an ischemic lesion in the left basal ganglia and concentric thickening of the vessel wall in the terminal portion of the bilateral ICAs. Despite maximal medical treatments for HIV-associated vasculopathy and possible opportunistic infections, bilateral ICA stenoses progressed, leading to a second hemodynamic stroke event. Because tissue plasminogen activator treatment failed, we performed STA-MCA bypass. A significant improvement in neurologic symptoms and cerebral blood flow was observed after surgery. No further stroke events occurred during the continuation of medical treatments. Conclusion This is the first case of STA-MCA bypass performed in a patient with recurrent ischemic stroke caused by HIV-associated vasculopathy. Although further evidence is needed, such treatment options can shed new light on the management of progressive HIV-associated vasculopathy, which is refractory to maximal medical treatment. [ABSTRACT FROM AUTHOR]