Stepwise Acquisition of Dialogue Act Through Human-Robot Interaction

A dialogue act (DA) represents the meaning of an utterance at the illocutionary force level (Austin 1962) such as a question, a request, and a greeting. Since DAs take charge of the most fundamental part of communication, we believe that the elucidation of DA learning mechanism is important for cognitive science and artificial intelligence. The purpose of this study is to verify that scaffolding takes place when a human teaches a robot, and to let a robot learn to estimate DAs and to make a response based on them step by step utilizing scaffolding provided by a human. To realize that, it is necessary for the robot to detect changes in utterance and rewards given by the partner and continue learning accordingly. Experimental results demonstrated that participants who continued interaction for a sufficiently long time often gave scaffolding for the robot. Although the number of experiments is still insufficient to obtain a definite conclusion, we observed that 1) the robot quickly learned to respond to DAs in most cases if the participants only spoke utterances that match the situation, 2) in the case of participants who builds scaffolding differently from what we assumed, learning did not proceed quickly, and 3) the robot could learn to estimate DAs almost exactly if the participants kept interaction for a sufficiently long time even if the scaffolding was unexpected.Comment: Published as a conference paper at IJCNN 201

Achieving Cooperative Behavior Based on Intention Estimation by Learning Combinations of Modules

A robot needs to process information appropriately depending on the environment or context. However, some of the abilities required by a robot are often common irrespective of the environment or context. In such situations, the learning agent should not learn the abilities again but use the learning results of previous tasks. In the field of the study of intellectual systems, models have been proposed that solve complex problems by combining modules, each of which serve a specific function such as recognition, planning, or action selection. The models can use the learning results of previous tasks in different environments or contexts by combining modules it has learnt. In this paper, we focus on achieving cooperative behavior based on intention estimation, and propose a model for a learning agent that can acquire combinations of modules using which the agent can achieve cooperative behavior based on intention estimation. The experimental results indicate that a desirable combination of the modules was acquired and the learning process suitably progressed

Dynamics of light-induced anomalous Hall effect in the three-dimensional Dirac semimetal Cd3_3As2_2

We experimentally study the dynamical behavior of the light-induced anomalous Hall effect in a three-dimensional Dirac semimetal, Cd$_3$As$_2$. An ultrashort, circularly polarized, multi-terahertz pump pulse breaks the time-reversal symmetry of a thin film sample. The resulting anomalous Hall effect is clearly observed through the polarization rotation of a single-cycle terahertz probe pulse. Comparing the experimental result with theory, we find that the field-induced injection current dominates the anomalous Hall effect during pump irradiation, while the Berry curvature of the Floquet-Weyl semimetal state does not appreciably contribute. Remarkably, even after pump irradiation, we observe an anomalous Hall effect that lasts for more than 10 ps. A model fit to the Hall conductivity spectrum reveals a relatively long scattering time over 400 fs. This result shows that circularly polarized light creates a polarization of the isospin degree of freedom in the Dirac semimetal, which labels the crystallographic point group representation of the overlapping Weyl semimetal bands. Our observation paves the way for conversion of a robust isospin flow into an electric current at room temperature, being a new analogue of the inverse spin Hall effect.Comment: 44 pages, 14 figure

Association of dorsal malunion in distal radius fractures with wrist osteoarthritis: Alterations of bone density and stress-distribution patterns in relation to deformation angles

Kazui A., Miyamura S., Shiode R., et al. Association of dorsal malunion in distal radius fractures with wrist osteoarthritis: Alterations of bone density and stress-distribution patterns in relation to deformation angles. Osteoarthritis and Cartilage, (2024); https://doi.org/10.1016/j.joca.2024.08.006.Objective: Distal radius fractures (DRFs) with dorsal malunion increase the risk of osteoarthritis (OA), although the cause of post-DRF OA is yet to be elucidated. To clarify the abnormal effects of a post-DRF dorsal radius deformity, we evaluated the bone density (BD) and stress-distribution patterns of the articular surface in dorsally malunited DRFs. Design: In 36 cases of dorsally malunited DRFs following extra-articular fractures, we generated three-dimensional computerized models of the malunited distal radius from computed tomography data and extracted the subchondral bones of the radiocarpal joint (RCJ) and distal radioulnar joint (DRUJ). Both BD and stress distribution in the subchondral bones were quantitatively evaluated by comparing the affected and normal sides. Correlations of alterations in high-BD distribution and deformation angles were analyzed. Results: The center of high-BD distribution from the center of the RCJ in the volar(-)-dorsal(+) direction was dorsal (0.56 ± 0.72 mm) on the affected side compared with the normal side (−0.15 ± 0.63 mm) [95% CI: 0.43, 1.00, P < 0.0001]. The maximum stress distribution was also dorsal on the affected side (2.34 ± 3.52 mm) compared with the normal side (−2.49 ± 1.62 mm) [95% CI: 0.89, 1.79, P < 0.0001]. The alterations in BD and stress distribution correlated with the dorsiflexion and radial deviation angles. In the DRUJ, there was no significant difference in BD between the affected and normal sides. Conclusions: In dorsally malunited DRFs, the alignment change of the RCJ resulted in high BD-concentration areas and stress distribution on the dorsal side of the radius, which may constitute a precursor for OA

Cubitus varus deformity following paediatric supracondylar humeral fracture remodelling predominantly in the sagittal direction: A three-dimensional analysis of eighty-six cases

The version of record of this article, first published in International Orthopaedics, is available online at Publisher’s website: https://doi.org/10.1007/s00264-024-06197-2.Purpose: Three-dimensional (3D) capacity for remodelling in cubitus varus deformity (CVD) after paediatric supracondylar humeral fractures (PSHFs) remains unelucidated. This study investigated remodelling patterns after PSHFs by examining 3D deformity distribution over time after injury. Methods: Computed tomography (CT) data of 86 patients with CVD after PSHFs were analysed. The 3D deformity angles in the sagittal, coronal, and axial directions were assessed and correlated with the duration between the age at injury and CT evaluation. For the subgroup analysis, we performed the same correlation analysis in a younger (< 8 years old) and an older group (≥ 8 years old); we categorized the duration into early (< 2 years), middle (≥ 2 to < 5 years), and late periods (≥ 5 years) and compared the deformity angles of each direction among the three groups. Results: Sagittal deformity showed a moderate correlation with the duration of deformity (r = -0.54; P < 0.001), while coronal and axial deformities showed a negligible correlation. Sagittal deformity showed moderate correlations with the duration in the younger group (r = -0.62; P < 0.001) and weak correlations in the older group (r = -0.37; P = 0.091). In the sagittal direction, the deformity angle in the early period was significantly larger than those in the mid and late periods (P < 0.001). However, there were no significant differences among the three groups in the coronal and axial directions. Conclusion: Sagittal deformities in CVDs are capable of remodelling, especially in the early period and at a younger age, whereas coronal and axial deformities are less likely to undergo remodelling

Robot-directed speech detection using multimodal semantic confidence based on speech, image, and motion

ABSTRACT In this paper, we propose a novel method to detect robotdirected (RD) speech that adopts the Multimodal Semantic Confidence (MSC) measure. The MSC measure is used to decide whether the speech can be interpreted as a feasible action under the current physical situation in an object manipulation task. This measure is calculated by integrating speech, image, and motion confidence measures with weightings that are optimized by logistic regression. Experimental results show that, compared with a baseline method that uses speech confidence only, MSC achieved an absolute increase of 5% for clean speech and 12% for noisy speech in terms of average maximum F-measure

Plaque REgression with Cholesterol absorption Inhibitor or Synthesis inhibitor Evaluated by IntraVascular UltraSound (PRECISE-IVUS Trial): Study protocol for a randomized controlled trial

AbstractBackgroundAlthough the positive association between achieved low-density lipoprotein cholesterol (LDL-C) level and the risk of coronary artery disease (CAD) has been confirmed by randomized studies with statins, many patients remain at high residual risk of events suggesting the necessity of novel pharmacologic strategies. The combination of ezetimibe/statin produces greater reductions in LDL-C compared to statin monotherapy.PurposeThe Plaque REgression with Cholesterol absorption Inhibitor or Synthesis inhibitor Evaluated by IntraVascular UltraSound (PRECISE-IVUS) trial was aimed at evaluating the effects of ezetimibe addition to atorvastatin, compared with atorvastatin monotherapy, on coronary plaque regression and change in lipid profile in patients with CAD.MethodsThe study is a prospective, randomized, controlled, multicenter study. The eligible patients undergoing IVUS-guided percutaneous coronary intervention will be randomly assigned to receive either atorvastatin alone or atorvastatin plus ezetimibe (10mg) daily using a web-based randomization software. The dosage of atorvastatin will be increased by titration within the usual dose range with a treatment goal of lowering LDL-C below 70mg/dL based on consecutive measures of LDL-C at follow-up visits. IVUS will be performed at baseline and 9–12 months follow-up time point at participating cardiovascular centers. The primary endpoint will be the nominal change in percent coronary atheroma volume measured by volumetric IVUS analysis.ConclusionPRECISE-IVUS will assess whether the efficacy of combination of ezetimibe/atorvastatin is noninferior to atorvastatin monotherapy for coronary plaque reduction, and will translate into increased clinical benefit of dual lipid-lowering strategy in a Japanese population

Cell motion predicts human epidermal stemness

Image-based identification of cultured stem cells and noninvasive evaluation of their proliferative capacity advance cell therapy and stem cell research. Here we demonstrate that human keratinocyte stem cells can be identified in situ by analyzing cell motion during their cultivation. Modeling experiments suggested that the clonal type of cultured human clonogenic keratinocytes can be efficiently determined by analysis of early cell movement. Image analysis experiments demonstrated that keratinocyte stem cells indeed display a unique rotational movement that can be identified as early as the two-cell stage colony. We also demonstrate that α6 integrin is required for both rotational and collective cell motion. Our experiments provide, for the first time, strong evidence that cell motion and epidermal stemness are linked. We conclude that early identification of human keratinocyte stem cells by image analysis of cell movement is a valid parameter for quality control of cultured keratinocytes for transplantation

Impact of Dual Lipid-Lowering Strategy With Ezetimibe and Atorvastatin on Coronary Plaque Regression in Patients With Percutaneous Coronary Intervention The Multicenter Randomized Controlled PRECISE-IVUS Trial

AbstractBackgroundDespite standard statin therapy, a majority of patients retain a high “residual risk” of cardiovascular events.ObjectivesThe aim of this study was to evaluate the effects of ezetimibe plus atorvastatin versus atorvastatin monotherapy on the lipid profile and coronary atherosclerosis in Japanese patients who underwent percutaneous coronary intervention (PCI).MethodsThis trial was a prospective, randomized, controlled, multicenter study. Eligible patients who underwent PCI were randomly assigned to atorvastatin alone or atorvastatin plus ezetimibe (10 mg) daily. Atorvastatin was uptitrated with a treatment goal of low-density lipoprotein cholesterol (LDL-C) <70 mg/dl. Serial volumetric intravascular ultrasound was performed at baseline and again at 9 to 12 months to quantify the coronary plaque response in 202 patients.ResultsThe combination of atorvastatin/ezetimibe resulted in lower levels of LDL-C than atorvastatin monotherapy (63.2 ± 16.3 mg/dl vs. 73.3 ± 20.3 mg/dl; p < 0.001). For the absolute change in percent atheroma volume (PAV), the mean difference between the 2 groups (–1.538%; 95% confidence interval [CI]: –3.079% to 0.003%) did not exceed the pre-defined noninferiority margin of 3%, but the absolute change in PAV did show superiority for the dual lipid-lowering strategy (–1.4%; 95% CI: –3.4% to –0.1% vs. –0.3%; 95% CI: –1.9% to 0.9% with atorvastatin alone; p = 0.001). For PAV, a significantly greater percentage of patients who received atorvastatin/ezetimibe showed coronary plaque regression (78% vs. 58%; p = 0.004). Both strategies had acceptable side effect profiles, with a low incidence of laboratory abnormalities and cardiovascular events.ConclusionsCompared with standard statin monotherapy, the combination of statin plus ezetimibe showed greater coronary plaque regression, which might be attributed to cholesterol absorption inhibition–induced aggressive lipid lowering. (Plaque Regression With Cholesterol Absorption Inhibitor or Synthesis Inhibitor Evaluated by Intravascular Ultrasound [PRECISE-IVUS]; NCT01043380

A Noise-Tolerant Hybrid Model of a Global and a Local Learning Module

Proposed is GLLL2, a hybrid architecture of a global and a local learning module, which learns default and exceptional knowledge respectively from noisy examples. The global learning module, which is a feedforward neural network, captures global trends gradually, while the local learning module stores local exceptions quickly. The latter module distinguishes noise from exceptions, and learns only exceptions, which ability makes GLLL2 noise-tolerant. The results of experiments show the process in which training examples are formed into default and exceptional knowledge, and demonstrate that the predictive accuracy, the space efficiency, and the training efficiency of GLLL2 is higher than those of each individual module. Introduction In cognitive science, whether learners induce rules or remember exemplars has been at issue recently. In particular, learning processes of quasi-regular tasks that involve both regularities and exceptions has attracted considerable attention. We developed G..