Symmetric Joint Research Articles

Information Correlation in a 2 × 2 Game and an Extension of Purification Rationale

In this paper, we study a 2 × 2 Bayesian entry game with correlated private information. The distribution of private information is modelled by a symmetric joint normal distribution. Therefore, the correlation coefficient of the private information distribution reflects the degree of dependence of players' private information. Under such specification, players' private information can be correlated flexibly, which is not confined to the typical additive specification of private payoff shocks or private information by Carlson and van Damme (1993), where the private information is correlated due to the common payoff shock. In our game, if the private information is correlated, we find that given the variances of the private information, there exists a restriction on the degree of correlation of players' private information that allows the game can be solved by cutoff strategies. Specifically, given the variances of the private information, if players' private information in strategic substitutes (strategic complements) Bayesian games are positively (negatively) correlated, the range of correlation coefficient that allows the game can be solved by cutoff strategies is restricted so that if the correlation is out of the range, the game cannot be solved by cutoff strategies. Alternatively, given positive (negative) correlation of private information, the value of variances that allows a strategic substitutes (strategic complements) Bayesian games can be solved by cutoff strategies are restricted within certain range. If the value of variances fall out of the range, the Bayesian game cannot be solved by cutoff strategies. However, given negative (positive) correlation of players' private information in strategic substitutes (strategic complements) Bayesian games, in which the Bayesian games can always be solved by cutoff strategies, we prove that as the variances converge to zero, all pure strategy Bayesian Nash equilibria of the perturbed games converge to the respective Nash equilibria of the corresponding strategic substitutes (strategic complements) complete information games. Based on the result, we conclude that the purification rationale proposed by Harsanyi (1973) can be extended to games with dependent perturbation errors that follow a symmetric joint normal distribution if the correlation coefficient is positive for the strategic complements games or negative for the strategic substitutes games.

Symmetry-aware kinematic skeleton generation of a 3D human body model

In this paper, an automatic method is proposed to generate a symmetry-aware kinematic skeleton for a human body model with an arbitrary pose and orientation. First, a template kinematic skeleton with semantics is embedded into the input human body model. Then, the joints of the embedded kinematic skeleton are refined according to the geometry of the human body model and some prior knowledge. Finally, a specific local coordinate system is defined on the kinematic skeleton and is used to distinguish the symmetry of the kinematic skeleton. In this way, the symmetric joints of the kinematic skeleton, e.g., the left knee joint and the right knee joint, can be distinguished. Quantitative and qualitative analysis and comparison show that the proposed method can generate a symmetry-aware kinematic skeleton with accurate joints and has no restrictions on the pose and orientation of the input human body model. Moreover, this paper presents validation of the proposed method in many applications, such as shape alignment, shape deformation, shape co-segmentation and shape correspondence.

P29 Use of novel biologic therapies for arthropathy affecting common variable immunodeficiency patients

Abstract Background CVID is the most common adult immunodeficiency with an incidence of 1:25000. It is characterised by hypogammaglobulinaemia and recurrent bacterial infections. Patients also develop granulomatous interstitial lung disease and are at increased risk of lymphoma. Autoimmune disease, most commonly AIHA, ITP and thyroiditis, occurs at a rate of 25%. Previous studies suggested that 3% of patients have inflammatory arthritis, but from our experience a higher proportion complain of chronic arthralgias. Treating arthropathy in CVID is challenging; examination and inflammatory markers may be normal and there is concern about the risk of infections if using methotrexate or biologics. Methods We present a series of 7 patients with arthropathy in CVID. We chose DMARDs based on the individual case, tailor-made to the patients clinical and immunologic status. Results Patients had longstanding symptoms, with a median duration of 11 years. All patients had disabling joint pain, in three it was the most prominent symptom of their illness. All patients had pain/swelling in a typical symmetrical small joint polyarthritis distribution. Fatigue was also prominent. On examination three patients had clear evidence of synovitis, one had tenderness but no swelling, and three had no evidence of synovitis; there was no deformity. No patient had positive autoantibodies. Three had chronically raised CRP/ESR, one had raised inflammatory markers during flares, but the other three had normal markers. Prednisolone (10-15 mg) controlled arthritic symptoms. There was little response to conventional DMARDS or rituximab. Two patients treated with abatacept showed improvement in symptoms, but one died from PJP pneumonia. Two patients treated with baricitinib showed improvement in symptoms but one relapsed after 5 months (Table 1). Conclusion Arthopathy is a common, and probably under-diagnosed, feature of CVID. It is difficult to treat, with a poor response seen to most DMARDs. We have seen promising results with Baricitinib and propose using it first line in patients with disabling rheumatic symptoms. There may be a role for abatacept in co-existent severe joint and lung disease. A striking proportion, 4/7 (versus 10% in general CVID population), of patients had a causal genetic mutation identified. Arthropathy may, therefore, push immunologists towards genetic testing. Disclosures R. Henneberry None. S. Burns None. R. Stratton None. D.M. Lowe None.

Evaluation of the diagnostic performance of 18F-NaF positron emission tomography/computed tomography in patients with suspected ankylosing spondylitis according to the Assessment of SpondyloArthritis International Society criteria

BACKGROUND CONTEXTPositron emission tomography (PET) is a potential imaging technique for the diagnosis of AS. The visualization of physiological change makes PET potentially suitable for early detection of inflammatory processes, even before anatomical changes occur. Thus, PET might provide specificity via the use of receptor targeting tracers and allows quantification of disease activity in order to accurately monitor therapeutic effects. PURPOSETo examine fluorine-18 sodium fluoride (18F-NaF) PET/computed tomography (PET/CT) findings in patients with inflammatory low back pain and evaluate the utility of this modality in the diagnosis of ankylosing spondylitis (AS) according to the Assessment of SpondyloArthritis International Society (ASAS) criteria. STUDY DESIGNRetrospective cohort study. PATIENTS SAMPLESixty-eight patients who underwent 18F-NaF PET/CT imaging between April 2015 and April 2017 for evaluation of inflammatory low back pain. OUTCOME MEASURESWe defined AS-positive lesions on PET/CT as symmetric sacroiliac joint uptake that suggests sacroiliitis, syndesmophytes on the spine, and enthesopathy at any site. METHODSAll patients were evaluated using the ASAS criteria and assigned to either the AS or the control group. The diagnostic criteria of AS on PET/CT images were defined as 18F-NaF PET/CT images with at least one of AS-positive findings. RESULTSThe diagnostic rate of AS was 72.1% among the 68 patients according to the ASAS criteria. The baseline characteristics between the two groups differed significantly in terms of serum C-reactive protein levels and the presence of human leucocyte antigen-B27. Compared to the control group, in the AS group, 39 patients (79.5%) exhibited typical 18F-NaF PET/CT-positive findings, such as enthesopathy (65.3%, p=.003), syndesmophytes (61.2%, p=.006) and symmetric sacroiliitis (67.3%, p=.001). PET-positive findings had significantly higher area under the curve values than did single 18F-NaF PET/CT- positive findings, and they had the best performance for concordant diagnosis according to the ASAS criteria. CONCLUSIONS18F-NaF PET/CT yielded significantly different findings between the two groups according to the ASAS criteria and is useful for diagnosing AS.

Color fraction as a useful method of imaging synovium vascularization in patients with high activity of rheumatoid arthritis.

Rheumatoid arthritis (RA) is an autoimmune disease with joint inflammation and destruction as the main features that appears with prevalence of 1 to 2% of the general population. Women are three times more likely to suffer from RA than men. Rheumatoid arthritis occurs at any age but commonly over 40–50 years old. In the course of RA each joint may be involved but most frequently the proximal interphalangeal and metacarpophalangeal joints of the hands, wrists, and also small joints of the feet are affected.Symmetrical joint swelling with overgrowth of synovium and hypervascularization confirmed in power Doppler ultrasound imaging are very characteristic for RA. Quantification of vascularization with the color fraction index may be a useful tool to monitor disease activity and in evaluation of inflammation in scientific research.This article aims to present this imaging diagnostic method based on the literature.

Mechanical Behaviors of a Symmetrical Bolt Fasten Wedge Active Joint for Braced Excavations

Joint-failure of steel tube bracing structures usually causes an excavation accident. A symmetrical bolt fasten wedge (BFW) active joint has been innovatively developed in this paper, which overcomes the shortcomings of the traditional steel wedge (SW) active joint. Three full-scale BFW active joint specimens were manufactured for field operation tests. The test results show that the proposed active joint had a good construction feasibility and a wide applicability. After the field operation tests, axial compression experiments were implemented. Meanwhile, a series of numerical simulations were performed. The numerical results agreed with that of the experiments. Both showed that the working principle and mechanical principle of the BFW active joint was reasonable and ingenious; it had outstanding mechanical properties. Overall, the BFW active joint had the advantages of structure and mechanical properties, and it is suitable for popularization and application.

Spring Effects on Workspace and Stiffness of a Symmetrical Cable-Driven Hybrid Joint

This paper aims to investigate how to determine the basic parameters of the helical compression spring which supports a symmetrical cable-driven hybrid joint (CDHJ) towards the elbow joint of wheelchair-mounted robotic manipulator. The joint design of wheelchair-mounted robotic manipulator needs to consider lightweight but robust, workspace requirements, and variable stiffness elements, so we propose a CDHJ which becomes a variable stiffness joint due the spring under bending and compression provides nonlinear stiffness characteristics. Intuitively, different springs will make the workspace and stiffness of CDHJ different, so we focus on studying the spring effects on workspace and stiffness of CDHJ for its preliminary design. The key to workspace and stiffness analysis of CDHJ is the cable tension, the key to calculate the cable tension is the lateral bending and compression spring model. The spring model is based on Castigliano’s theorem to obtain the relationship between spring force and displacement. The simulation results verify the correctness of the proposed spring model, and show that the spring, with properly chosen parameters, can increase the workspace of CDHJ whose stiffness also can be adjusted to meet the specified design requirements. Then, the modelling method can be extended to other cable-driven mechanism with a flexible compression spring.

Parametric Formulae for Elastic Stress Concentration Factor at the Weld Toe of Distorted Butt-Welded Joints.

The evaluation of the stress concentration factor (SCF) at the notches of welds is of importance, especially for butt-welded joints that are widespread in the industry. Some empirical formulae can be found in the literature to estimate the SCF at the weld toes of butt-welded joints, while few solutions are available for the distorted joints under tensile fatigue test conditions. In the present study, the existing SCF formulae for butt-welded joints loaded in tension are examined and discussed. The influence of the weld width on SCF, which is commonly ignored or misestimated by existing solutions, is investigated comprehensively based on a large set of two-dimensional (2D) finite element analyses. Consequently, a new precise parametric formula for the elastic SCF at the weld toe of geometrically symmetric butt-welded joints under tension is proposed, together with a wide application range. Moreover, the analysis is also extended to consider joints with angular distortion. A two-step finite element analysis is employed to simulate the clamping and loading procedures in the fatigue test. Similarly, the parametric formulae for the assessment of clamping-induced stress and SCF caused by angular distortion are carried out as well based on the results from finite element analyses. The formulae proposed by this paper are finally tested and proved to be valid and precise.

Warm Compress Reduced Pain Intensity of Arthritis Rheumatoid for Elderly People; Pre- and Post-test Design Study

Arthritis Rheumatoid (AR) is an autoimmune disease showing erosive of symmetric joint. It sometimes refers to many systems disturbances inside our bodies. The progressivity of AR has chronic fluctuation in daily life. AR can increase mortality risk, especially for chronic disabilities. This study aims to understand the effect of warm compress on the pain intensity of AR cases for elderly people. The method used in this study was a quasi-experimental one. The sampling method used was a purposive technique. The total number of respondents was 10, with 5 as the interventional arm of the study and 5 as the control arm. This study was conducted between February and July 2014. A paired t-test was used to identify whether the sample means for those in the intervention arm was statistically different from the average of the sample means drawn from those drawn from the control group presumed to be from the general elderly population who do not benefit from the particular intervention of a warm compress. What the author wanted to conclude on was whether the two samples at hand actually differ significantly from each other. The intensity of pre- and post-intervention using parametric statistics following the application of warm compress was noted and used as a basis of comparison. The result of the statistics formula showed the effectiveness of warm compress in decreasing the AR pain, the t-test was 6.000 and the p-value was lower than 0.05. It can be summarized that warm compress can be used to decrease pain intensity for elderly people with AR. Discussion – the result of this study can be used as a reference to conduct care among elder people who are affected by AR. People living in the community area should help their family member with AR on first aid.

Rheumatoid arthritis

Rheumatoid arthritis (RA) is a chronic inflammatory autoimmune disease. It is characterised by symmetrical joint involvement and extra-articular manifestations. Joint and periarticular tissue destruction occurs as a result of inflammation of the synovial joints, leading to functional impairment. Early diagnosis and treatment are the key to minimising the significant daily challenges experienced by patients and underpin more successful outcomes. This article will explore the recognition and management of RA in primary care, drawing on recently updated National Institute for Health and Care Excellence guidelines.

Mechanical behavior of FSW joint welded by a novel designed stationary shoulder tool

Abstract A novel stationary shoulder friction stir welding (SSFSW) tool was developed with provision for automatic removal of plasticized material entering into the shoulder during the welding. Main objective of this tool design was to obtain a symmetrical weld joint with narrow heat affected zone. Mechanical and metallurgical properties of AA2014 aluminium alloy SSFSW joint were compared with the conventional FSW joint. Sound weld joint with enhanced mechanical properties were obtained by the stationary shoulder tool. Optical microscopy, FESEM analysis along with EDS, transmission electron microscopy, XRD analysis, microhardness and toughness test were performed on both types of weld joint. Weld thermal cycle and heat generation were analyzed for stationary shoulder and conventional FSW tool and it was found that the SSFSW tool shoulder generates lesser heat than conventional FSW tool.

P45 Treat the arthritis, not just the chest

Abstract Background Very little literature exists in supporting the assessment and management of cystic fibrosis related arthritis (CFA) particularly in paediatric and adolescent cases. Methods A 12 year-old male with cystic fibrosis (CF) was admitted via A&E with severe joint pain that was thought to be associated with a respiratory infection and was treated accordingly. Repeated exacerbations of joint disease occurred every 1-2 months, lasting approximately 1 week with significant joint pain, stiffness, and reduced function. The patient did not feel his exacerbations of CFA were related to his respiratory symptoms, admitting he under reported arthritis symptoms to avoid being admitted for IV antibiotics. Initial rheumatology review resulted in treatment with IV antibiotics and piroxicam. Flares continued, prompting his CF physiotherapist and multidisciplinary team to seek further specialist review for his now longstanding symptoms. He scored 16 out of 50 on the McGill Pain Questionnaire (MPQ) with a visual analogue score (VAS) of 46 out of 100. At 16 years old he was seen by an MSK physiotherapy and rheumatology team working within a wider CF team. He had a 4 year history of symmetrical joint pain affecting knees, wrists and hands, on a background of bronchiectasis with previous non-tuberculous mycobacteria infection, cystic fibrosis related diabetes, and poor nutrition. He reported some episodes being so bad he was unable to get out of bed, and struggling with the stairs at college. He had 6 swollen and 8 tender joints including wrists, MCPs and knees. Ultrasound imaging of the wrists and hands showed confirmed active synovitis with grade 3 greyscale changes and grade 2 power Doppler. Hydroxychloroquine was commenced with naproxen as required, and wrist splints were provided. Results At follow-up he reported significant symptomatic improvement with occasional minor stiffness in wrists and knees which responded quickly to naproxen and was no longer limiting his activities. Repeat ultrasound confirmed improvement with no active power Doppler, but some ongoing grade 1 greyscale changes and a small wrist effusion. He has returned to previous function with an MPQ score of 0, and VAS of 10 out of 100. He reported improved quality of life due to reduced pain and fewer, shorter, and more manageable exacerbations. Conclusion Specialist review and commencement on disease modifying anti-rheumatic medication helped to manage CFA in this case. All cases of suspected CFA should be referred for specialist rheumatology opinion. CF physiotherapists are in an excellent position to identify cases and empowering the multidisciplinary team has been vital in this case. Further trials are required to investigate optimal management of CFA, but it seems likely that directly addressing the arthritis with disease modifying therapy may play an important role. Conflicts of Interest The authors declare no conflicts of interest.

Internal Material Flow Layers in AA6082-T6 Butt-Joints during Bobbin Friction Stir Welding

Bobbin friction stir welding with a double-sided tool configuration produces a symmetrical solid-state joint. However, control of the process parameters to achieve defect-free welds is difficult. The internal flow features of the AA6082-T6 butt-joints in bobbin friction stir welding were evaluated using a set of developed reagents and optical microscopy. The key findings are that the dark curved patterns (conventionally called 'flow-arms'), are actually oxidation layers at the advancing side, and at the retreating side are elongated grains with a high-density of accumulation of sub-grain boundaries due to dynamic recrystallization. A model of discontinuous flow within the weld is proposed, based on the microscopic observations. It is inferred that the internal flow is characterized by packets of material ('flow patches') being transported around the pin. At the retreating side they experience high localized shearing at their mutual boundaries, as evidenced in high density of sub-grain boundaries. Flow patches at the advancing side are stacked on each other and exposed to oxidization.

32. My PET investigation

IntroductionPolymyalgia rheumatica (PMR) is closely associated with giant cell arteritis, the most common cause of vasculitis in the elderly population. Diagnostic challenges may arise when patients present with marked systemic upset, raising concerns about a malignancy. Our patient initially presented with marked weight loss, anaemia and significantly raised CRP and ESR, prompting urgent referrals to gastroenterology and haematology to rule out a malignancy. He was eventually referred to the rheumatology team and a PET-CT demonstrated characteristic findings of polymyalgic-onset rheumatoid arthritis. We also explore the expanding role of PET imaging in other rheumatic disorders. Case descriptionA 65-year-old Caucasian gentleman presented to his GP in September 2018 with significant weight loss and general malaise. He had been managing large joint arthralgia by self-medicating with aspirin 300mg daily. Initial investigations by his GP demonstrated a normocytic anaemia, neutropaenia and low iron levels (haemoglobin 103g/L, MCV 86.9fL, neutrophil count 0.5x109/L, iron level 4umol/L). His past medical history was significant of hypercholesterolemia and a right inguinal repair. He had no regular prescribed medications. He worked as an electrical engineer. He had a significant smoking history of 40-pack-years. He was initially referred to the colorectal and haematology teams under the 2-week-wait rule. Video capsule endoscopy, cross-sectional imaging and bone marrow trephine identified no occult malignancy. His ESR was markedly elevated at 133mm/h with a corresponding CRP of 134mg/L. Serum protein electrophoresis was consistent with chronic inflammation. He was subsequently referred to the rheumatology clinic in December 2018 by the haematologists in view of the raised inflammatory markers.At initial review, he reported right knee pain and symmetrical small joint arthralgia of the hands. He also described pain affecting the cervical spine, both shoulders and hips with significant early morning stiffness. Careful questioning revealed no symptoms of a connective tissue disorder. Examination demonstrated marked, symmetrical synovitis over his metacarpophalangeal, proximal interphalangeal and wrist joints. Immunology tests were all negative. Due to ongoing concerns regarding a malignancy a PET-CT scan was requested. This demonstrated widespread FDG-avid symmetrical polyarthropathy in a rheumatoid pattern in addition to enthesopathy in keeping with PMR. There was no evidence of large vessel vasculitis. After 3 months of investigations under multiple specialties, the patient was diagnosed with polymyalgic-onset rheumatoid arthritis. He was started on prednisolone with an excellent clinical response. His CRP improved to 17mg/L. His full blood count also normalised which eventually allowed the introduction of methotrexate.DiscussionRheumatologists are frequently asked to assess patients with unexplained elevated inflammatory markers or multisystem diseases. It is important to remember that constitutional symptoms can be the first presentation of a rheumatic disorder, particularly when an occult malignancy and infection have been ruled out. Although this patient had clinically apparent synovitis on clinical examination, his inflammatory markers were extremely elevated with marked systemic upset. Interestingly, PET-CT demonstrated typical features of PMR which were not apparent from the initial consultation with no evidence of large vessel vasculitis.PET imaging has been used extensively in oncology to identify malignant lesions but it is important to understand its expanding role in rheumatology in identifying active inflammation. It has been used in the diagnosis of large vessel vasculitides, including giant cell arteritis and Takayasu’s arteritis, and IgG4-related disease. Moreover, it is very useful in identifying the extent of the disease which may guide treatment decisions. PET-CT can also be used in the diagnosis and to assess the extent of disease in PMR. Typically, there is FDG uptake in the shoulders, sternoclavicular and hip joints. There is often increased extra-articular uptake between the spinous processes and ischial tuberosities. The use of PET-CT to diagnose PMR is not widespread as the diagnosis of PMR is usually evident based on the history, clinical findings and inflammatory markers. However, when there is marked systemic upset and/or very high inflammatory markers, it is important to consider utilising PET-CT to assess for concurrent occult malignancy or large vessel vasculitis. More recently, PET imaging has also been used in the diagnosis of early rheumatoid arthritis and some studies have shown that it is more sensitive and specific than MRI at picking up subclinical synovitis.Key learning pointsThis case highlights the usefulness of PET-CT as a diagnostic tool in patients who present with systemic illness. The use of PET-CT is two-fold; firstly, to rule out an occult malignancy and secondly, to look for other features that would support an alternative diagnosis. There are characteristic findings of PMR on PET-CT and as rheumatologists, we must be aware of the expanding role of PET-CT in our field so that it can be appropriately applied to our clinical practice. Conflicts of interestThe authors have declared no conflicts of interest.

Is Cervical Stabilization for All Cases of Chiari-I Malformation an Overkill? Evidence Speaks Louder Than Words!

Chiari I malformation is characterized by the downward displacement of cerebellar tonsils through the foramen magnum. While discussing the treatment options for Chiari I malformation, the points of focus include: (1) Has the well-established procedure of posterior fossa decompression become outdated and has been replaced by posterior C1–2 stabilization in every case? (2) In case posterior stabilization is required, should a C1–2 stabilization, rather than an occipitocervical fusion, be the only procedure recommended? The review of literature revealed that when there is bony instability like atlantoaxial dislocation (AAD), occipito-atlanto-axial facet joint asymmetry or basilar invagination (BI) associated with Chiari I malformation, one should address the anterior bony compression as well as perform stabilization. This takes care of the compromised canal at the foramen magnum and re-establishes the cerebrospinal fluid flow along the craniospinal axis; and also provides treatment for CVJ instability. In the cases with a pure Chiari I malformation without AAD or BI and with completely symmetrical C1–2 joints, however, posterior fossa decompression with or without duroplasty is sufficient to bring about neurological improvement. The latter subset of cases with pure Chiari I malformation have, thus, shown significant (>70%) rates of neurological improvement with posterior fossa decompression alone. A C1–2 posterior stabilization is a more stable construct due to the strong bony purchase provided by the C1–2 lateral masses and the short lever arm of the construct. However, in the cases with significant bleeding from paravertebral venous plexus; a very high BI, condylar hypoplasia and occipitalized atlas; gross C1–2 rotation or vertical C1–2 joints with unilateral C1 or C2 facet hypoplasia, as well as the presence of subaxial scoliosis; maldevelopment of the lateral masses and facet joints (as in very young patients); or, the artery lying just posterior to the C1–2 facet joint capsule (being endangered by the C1–2 stabilization procedure), it may be safer to perform an occipitocervical rather than a C1–2 fusion.

Indistinguishable single-mode photons from spectrally engineered biphotons.

We use pulsed spontaneous parametric down-conversion in KTiOPO4, with a Gaussian phase-matching function and a transform-limited Gaussian pump, to achieve near-unity spectral purity in heralded single photons at telecommunication wavelength. Theory shows that these phase-matching and pump conditions are sufficient to ensure that a biphoton state with a circularly symmetric joint spectral intensity profile is transform limited and factorable. We verify the heralded-state spectral purity in a four-fold coincidence measurement by performing Hong-Ou-Mandel interference between two independently generated heralded photons. With a mild spectral filter we obtain an interference visibility of 98.4±1.1% which corresponds to a heralded-state purity of 99.2%. Our heralded photon source is potentially an essential resource for measurement-based quantum information processing and quantum network applications.

Full-body motion assessment: Concurrent validation of two body tracking depth sensors versus a gold standard system during gait

RGB-D cameras provide 3-D body joint data in a low-cost, portable and non-intrusive way, when compared with reference motion capture systems used in laboratory settings. In this contribution, we evaluate the validity of both Microsoft Kinect versions (v1 and v2) for motion analysis against a Qualisys system in a simultaneous protocol. Two different walking directions in relation to the Kinect (towards – WT, and away – WA) were explored. For each gait trial, measures related with all body parts were computed: velocity of all joints, distance between symmetrical joints, and angle at some joints. For each measure, we compared each Kinect version and Qualisys by obtaining the mean true error and mean absolute error, Pearson’s correlation coefficient, and optical-to-depth ratio. Although both Kinect v1 and v2 and/or WT and WA data present similar accuracy for some measures, better results were achieved, overall, when using WT data provided by the Kinect v2, especially for velocity measures. Moreover, the velocity and distance presented better results than angle measures. Our results show that both Kinect versions can be an alternative to more expensive systems such as Qualisys, for obtaining distance and velocity measures as well as some angles metrics (namely the knee angles). This conclusion is important towards the off-lab non-intrusive assessment of motor function in different areas, including sports and healthcare.

Skin inflammatory reactions to capsaicin in rheumatoid arthritis patients compared to healthy controls.

Previous studies have examined the role of sensory nerves and neural mediators in symmetrical joint inflammation and autoimmunity in rheumatoid arthritis (RA). In this study, we sought to examine the association between capsaicin skin test and disease activity in RA patients. Eighty RA patients (case group) and 20 healthy volunteers were enrolled in this experiment. The subjects in case group were calcified to newly diagnosed patients and those previously diagnosed with RA. A topical solution of capsaicin (0.075%) was applied on the volar forearm during the skin test, and evaluations were done after 5, 10, and 20 min. The parameters recorded in capsaicin skin test were time to tingling, area of induration (cm2), and area of redness (cm2). A faster capsaicin skin reaction was observed in healthy controls compared to the case group (p=0.02). Newly diagnosed and previously diagnosed RA patients were not significantly different in terms of reaction latency (p=0.06). The redness area after 15 (p=0.04) and 20 (p=0.001) min was significantly larger in previously diagnosed RA patients than in newly diagnosed ones. The ​​area of redness and time to tingling did not show any difference between active and inactive RA patients, but after 15 and 20 min, the area of redness was significantly greater in inactive RA patients compared to active RA patients (p=0.01 and p=0.03, respectively). This study suggested that capsaicin skin test is not an efficient tool for the examination of synovial inflammation and disease activity in RA.

STATIC STRENGTH COMPUTATION METHODOLOGY FOR ADHESIVE JOINTS

A method to determine the static strength of structural adhesive joints is proposed, which takes into account the ultimate shear strain reduction caused by pullout stress. Specimens with different proportions of pullout and shear stress were tested. The results demonstrated that the analytically determined strength of the symmetrical double lap joint is in good agreement with previously obtained experimental data by other authors.

Automatic Musculoskeletal and Neurological Disorder Diagnosis With Relative Joint Displacement From Human Gait.

Musculoskeletal and neurological disorders are common devastating companions of ageing, leading to a reduction in quality of life and increased mortality. Gait analysis is a popular method for diagnosing these disorders. However, manually analyzing the motion data is a labor-intensive task, and the quality of the results depends on the experience of the doctors. In this paper, we propose an automatic framework for classifying musculoskeletal and neurological disorders among older people based on 3D motion data. We also propose two new features to capture the relationship between joints across frames, known as 3D Relative Joint Displacement (3DRJDP) and 6D Symmetric Relative Joint Displacement (6DSymRJDP), such that the relative movement between joints can be analyzed. To optimize the classification performance, we adapt feature selection methods to choose an optimal feature set from the raw feature input. Experimental results show that we achieve a classification accuracy of 84.29% using the proposed relative joint features, outperforming existing features that focus on the movement of individual joints. Considering the limited open motion database for gait analysis focusing on such disorders, we construct a comprehensive, openly accessible 3D full-body motion database from 45 subjects.