47 research outputs found
Physically Consistent Preferential Bayesian Optimization for Food Arrangement
This paper considers the problem of estimating a preferred food arrangement
for users from interactive pairwise comparisons using Computer Graphics
(CG)-based dish images. As a foodservice industry requirement, we need to
utilize domain rules for the geometry of the arrangement (e.g., the food layout
of some Japanese dishes is reminiscent of mountains). However, those rules are
qualitative and ambiguous; the estimated result might be physically
inconsistent (e.g., each food physically interferes, and the arrangement
becomes infeasible). To cope with this problem, we propose Physically
Consistent Preferential Bayesian Optimization (PCPBO) as a method that obtains
physically feasible and preferred arrangements that satisfy domain rules. PCPBO
employs a bi-level optimization that combines a physical simulation-based
optimization and a Preference-based Bayesian Optimization (PbBO). Our
experimental results demonstrated the effectiveness of PCPBO on simulated and
actual human users.Comment: 8 pages, 10 figures, accepted by IEEE Robotics and Automation Letters
(RA-L) 202
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Development of a wearable assistive soft robotic device for elbow rehabilitation
The loss of motor function at the elbow joint can
result as a consequence of stroke. Stroke is a clinical illness resulting in long lasting neurological deficits often affecting somatosensory and motor cortices. More than half of those that recover from a stroke survive with disability in their upper arm and need rehabilitation therapy to help in regaining functions
of daily living. In this paper, we demonstrated a prototype of a low-cost, ultra-light and wearable soft robotic assistive device that could aid administration of elbow motion therapies to stroke patients. In order to assist the rotation of the elbow joint, the soft modules which consist of soft wedge-like cellular units was inflated by air to produce torque at the elbow joint.
Highly compliant rotation can be naturally realised by the elastic property of soft silicone and pneumatic control of air. Based on the direct visual-actuation control, a higher control loop utilised visual processing to apply positional control, the lower control loop was implemented by an electronic circuit to achieve the desired pressure of the soft modules by Pulse Width
Modulation. To examine the functionality of the proposed soft modular system, we used an anatomical model of the upper limb and performed the experiments with healthy participants
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Design and validation of a high DOF origami inspired soft actuated assistive exoskeleton arm and spine
This research presents the design, development, and validation of a high degree of freedom (DOF) exoskeleton actuated by origami-inspired soft inflatable modules. The objective was to create reliable soft actuators to provide safe and compliant movement assistance. Utilising lightweight 3D printing materials and origami-inspired soft flexible modules, the developed exoskeleton offers seven DOF to assist reaching motion of the upper limb. A passive rubber joint was incorporated for gravity compensation of the upper limb with elastic stability. The integrated exoskeleton consists of collapsible soft actuators made from polyethylene tubing, an ultra-lightweight structure with seven DOF, and real-time feedback through electronic goniometers. The validation included comprehensive testing of the soft actuators, and evaluating speed and accuracy. Torque measurements of the single module reached up to 4.46 Nm. A participant experiment in reaching motion demonstrated relatively slow but accurate movement, showcasing the effectiveness in assisting passive motion. This research successfully integrates soft actuators with a high DOF exoskeleton, highlighting its potential for providing movement assistance in various applications in future
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Design and validation of exoskeleton actuated by soft modules towards neurorehabilitation - vision-based control for precise reaching motion of upper limb
We demonstrated the design, production, and functional properties of the Exoskeleton Actuated by the Soft Modules (EAsoftM). Integrating the 3D printed exoskeleton with passive joints to compensate gravity and with active joints to rotate the shoulder and elbow joints resulted in ultra-light system that could assist planar reaching motion by using the vision-based control law. The EAsoftM can support the reaching motion with compliance realised by the soft materials and pneumatic actuation. In addition, the vision-based control law has been proposed for the precise control over the target reaching motion within the millimeter scale.
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Aiming at rehabilitation exercise for individuals, typically soft actuators have been developed for relatively small motions, such as grasping motion, and one of the challenges has been to extend their use for a wider range reaching motion. The proposed EAsoftM presented one possible solution for this challenge by transmitting the torque effectively along the anatomically aligned with a human body exoskeleton.
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The proposed integrated systems will be an ideal solution for neurorehabilitation where affordable wearable and portable systems are required to be customised for individuals with specific motor impairments
Genome-wide meta-analysis identifies multiple novel loci associated with serum uric acid levels in Japanese individuals
Gout is a common arthritis caused by elevated serum uric acid (SUA) levels. Here we investigated loci influencing SUA in a genome-wide meta-analysis with 121,745 Japanese subjects. We identified 8948 variants at 36 genomic loci (P<5 × 10–8) including eight novel loci. Of these, missense variants of SESN2 and PNPLA3 were predicted to be damaging to the function of these proteins; another five loci—TMEM18, TM4SF4, MXD3-LMAN2, PSORS1C1-PSORS1C2, and HNF4A—are related to cell metabolism, proliferation, or oxidative stress; and the remaining locus, LINC01578, is unknown. We also identified 132 correlated genes whose expression levels are associated with SUA-increasing alleles. These genes are enriched for the UniProt transport term, suggesting the importance of transport-related genes in SUA regulation. Furthermore, trans-ethnic meta-analysis across our own meta-analysis and the Global Urate Genetics Consortium has revealed 15 more novel loci associated with SUA. Our findings provide insight into the pathogenesis, treatment, and prevention of hyperuricemia/gout
Subtype-specific gout susceptibility loci and enrichment of selection pressure on ABCG2 and ALDH2 identified by subtype genome-wide meta-analyses of clinically defined gout patients
Objectives
Genome-wide meta-analyses of clinically defined gout were performed to identify subtype-specific susceptibility loci. Evaluation using selection pressure analysis with these loci was also conducted to investigate genetic risks characteristic of the Japanese population over the last 2000–3000 years.
Methods
Two genome-wide association studies (GWASs) of 3053 clinically defined gout cases and 4554 controls from Japanese males were performed using the Japonica Array and Illumina Array platforms. About 7.2 million single-nucleotide polymorphisms were meta-analysed after imputation. Patients were then divided into four clinical subtypes (the renal underexcretion type, renal overload type, combined type and normal type), and meta-analyses were conducted in the same manner. Selection pressure analyses using singleton density score were also performed on each subtype.
Results
In addition to the eight loci we reported previously, two novel loci, PIBF1 and ACSM2B, were identified at a genome-wide significance level (p<5.0×10–8) from a GWAS meta-analysis of all gout patients, and other two novel intergenic loci, CD2-PTGFRN and SLC28A3-NTRK2, from normal type gout patients. Subtype-dependent patterns of Manhattan plots were observed with subtype GWASs of gout patients, indicating that these subtype-specific loci suggest differences in pathophysiology along patients’ gout subtypes. Selection pressure analysis revealed significant enrichment of selection pressure on ABCG2 in addition to ALDH2 loci for all subtypes except for normal type gout.
Conclusions
Our findings on subtype GWAS meta-analyses and selection pressure analysis of gout will assist elucidation of the subtype-dependent molecular targets and evolutionary involvement among genotype, phenotype and subtype-specific tailor-made medicine/prevention of gout and hyperuricaemia