An improved corner dealiasing and recognition algorithm for 2D Wadell roundness computation.

This paper optimizes the 2D Wadell roundness calculation of particles based on digital image processing methods. An algorithm for grouping corner key points is proposed to distinguish each independent corner. Additionally, the cyclic midpoint filtering method is introduced for corner dealiasing, aiming to mitigate aliasing issues effectively. The relationships between the number of corner pixels (m), the central angle of the corner (α) and the parameter of the dealiasing degree (n) are established. The Krumbein chart and a sandstone thin section image were used as examples to calculate the 2D Wadell roundness. A set of regular shapes is calculated, and the error of this method is discussed. When α ≥ 30°, the maximum error of Wadell roundness for regular shapes is 5.21%; when 12° ≤ α < 30°, the maximum error increases. By applying interpolation to increase the corner pixels to the minimum number (m0) within the allowable range of error, based on the α-m0 relational expression obtained in this study, the error of the corner circle can be minimized. The results indicate that as the value of m increases, the optimal range interval for n also widens. Additionally, a higher value of α leads to a lower dependence on m. The study's results can be applied to dealiasing and shape analysis of complex closed contours.

Development of a BIM-based bridge maintenance system (BMS) for managing defect data.

Bridges might experience many defects during use, such as pavement cracks and reinforcement corrosion, which easily produce an accumulated impact that threatens bridge safety. Thus, there is a need for the regular inspection and maintenance of bridges. This paper presents a bridge maintenance system (BMS) based on building information modelling (BIM), which is utilized in bridge defect information management using a digitalization method. A bridge defect three-dimensional BIM (BIM3D) library is established and combined with a bridge model to visualize bridge defect conditions. Based on bridge inspection data, bridge defect information is digitally classified and encoded according to the international framework for dictionaries (IFD) standard and used to establish a database. An evaluation of bridge technical conditions is performed, and the results are graded and displayed in different colours, reflecting the visualization function of BIM technology. Maintenance suggestions are provided according to the range of bridge technical condition scores, reflecting the informatization function of BIM technology. With the Xinjiang Cocodala Bridge in China as a case study, a bridge BIM3D model and inspection data are imported into the BMS to utilize the functions of 'visualization of bridge defect conditions', 'evaluation of bridge technical conditions' and 'recommendations of bridge maintenance methods'.

The Dorsal 4-finger Technique: A Novel Method to Examine Metacarpophalangeal Joints in Patients with Rheumatoid Arthritis.

OBJECTIVE: To describe the dorsal 4-finger technique (DFFT) in examining metacarpophalangeal (MCP) joints of patients with rheumatoid arthritis (RA) and compare it to the traditional 2-finger technique (TFT) using ultrasound (US) as a gold standard. METHODS: Four rheumatologists evaluated 180 MCP joints of 18 patients with RA. All patients underwent US for greyscale (GSUS) and power Doppler US (PDUS). Agreements between rheumatologists, the 2 techniques, and US were evaluated using Cohen κ and the first-order agreement coefficient (AC1) κ methods. RESULTS: The population comprised 17 females (94.4%) with a mean (SD) age and disease duration of 56.8 (14.4) and 21.8 (12.9) years, respectively. Eight patients (44.4%) were taking methotrexate monotherapy, while 10 patients (55.6%) were receiving biologics. US evaluation revealed 69 (38.3%) and 30 (16.7%) joints exhibited synovitis grade 2-3 by GSUS and PDUS, respectively. Effusion was documented in 30 joints (16.7%). The mean intraobserver agreement using the DFFT and TFT were 80.5% and 86%, respectively. The mean interobserver agreements using the DFFT and TFT were 84% and 74%, respectively. κ agreement with US findings was similar for both techniques in tender joints but was higher for the DFFT in nontender joints (0.33 vs 0.07, p = 0.015 for GSUS) and (0.48 vs 0.11, p = 0.002 for PDUS). The DFFT had a higher sensitivity in detecting ballottement by GSUS (0.47 vs 0.2, p < 0.001) and PDUS (0.60 vs 0.27, p < 0.001). CONCLUSION: The DFFT is a novel, reproducible, and reliable method to examine MCP joints, and it has a better correlation with US than the traditional TFT.

Thresholds for the 28-joint disease activity score (DAS28) using C-reactive protein are lower compared to DAS28 using erythrocyte sedimentation rate in early rheumatoid arthritis.

OBJECTIVES: The 28-Joint Disease Activity Score (DAS28) using C-reactive protein (CRP) and DAS28 using erythrocyte sedimentation rate (DAS28-ESR) may not be interchangeable. We sought to compare and estimate optimal thresholds for the DA28-CRP for use in early rheumatoid arthritis (ERA). METHODS: Patients from the Canadian Early Arthritis Cohort with baseline and 12 months' data for both DAS28-ESR and DAS28-CRP were examined for correlations and differences between DAS28-CRP and DAS28-ESR across their range of values. Receiver operating characteristic analysis identified thresholds for DAS28-CRP that best corresponded to established thresholds for the DAS28-ESR using the total sample, then stratified by age and sex. Agreement between DAS28-CRP and DAS28-ESR thresholds was assessed with the kappa statistic. RESULTS: The sample included 995 patients with mean (SD) age of 53.7 (14.5) years, 5.8 (2.9) months of symptom duration and 74% were female. DAS28-CRP and DAS28-ESR scores were highly correlated (r= 0.92, p<0.0001), however DAS28-CRP values were consistently lower than DAS28-ESR values. Calculated thresholds for DAS28-CRP were lower with 2.5 for remission, 2.9 for low disease activity, and 4.6 for high disease activity but showed moderate agreement with the DAS28-ESR thresholds (kappa=0.70). CONCLUSIONS: In this large sample of ERA patients, newly estimated thresholds for DAS28-CRP were consistently lower than DAS28-ESR thresholds across the spectrum of disease activity. This may have important clinical implications if inflammatory markers are used interchangeably. Additional external validation of our findings is needed.

The effect of rheumatoid arthritis-associated autoantibodies on the incidence of cardiovascular events in a large inception cohort of early inflammatory arthritis.

Objective: . RA is associated with an increased risk of cardiovascular events (CVEs). The objective was to estimate independent effects of RA autoantibodies on the incident CVEs in patients with early RA. Methods: Patients were enrolled in the Canadian Early Inflammatory Arthritis Cohort, a prospective multicentre inception cohort. Incident CVEs, including acute coronary syndromes and cerebrovascular events, were self-reported by the patient and partially validated by medical chart review. Seropositive status was defined as either RF or ACPA positive. Multivariable Cox proportional hazards survival analysis was used to estimate the effects of seropositive status on incident CVEs, controlling for RA clinical variables and traditional cardiovascular risk factors. Results: . A total of 2626 patients were included: the mean symptom duration at diagnosis was 6.3 months ( s . d . 4.6), the mean age was 53 years ( s . d . 15), 72% were female and 86% met classification criteria for RA. Forty-six incident CVEs occurred over 6483 person-years [incidence rate 7.1/1000 person-years (95% confidence interval 5.3, 9.4)]. The CVE rate did not differ in seropositive vs seronegative subjects and seropositivity was not associated with incident CVEs in multivariable Cox regression models. Baseline covariates independently associated with incident CVEs were older age, a history of hypertension and a longer duration of RA symptoms prior to diagnosis. Conclusion: The rate of CVEs early in the course of inflammatory arthritis was low; however, delays in the diagnosis of arthritis increased the rate of CVEs. Hypertension was the strongest independent risk factor for CVEs. Results support early aggressive management of RA disease activity and co-morbidities to prevent severe complications.

Predicting Low Disease State and Remission in Early Rheumatoid Arthritis in the First Six Months, Comparing the Simplified Disease Activity Index and European League Against Rheumatism Response Measures: Results From an Early Arthritis Cohort.

OBJECTIVE: To compare the European League Against Rheumatism (EULAR) and Simplified Disease Activity Index 50% (SDAI50) response measures (RMs) and their impact on future response to treatment in patients with early rheumatoid arthritis (ERA). METHODS: Biologic agent-naive ERA patients from the Canadian Early Arthritis Cohort study with complete data at baseline, 3, and 6 months were evaluated. Kappa statistics were used to evaluate the agreement between the EULAR (moderate or good response) and SDAI50 RMs. The RMs at 3 months were also compared for their ability to predict low disease activity state (LDAS) or remission (REM) at 6 months. RESULTS: A total of 1,124 patients were evaluated. Of those, 215 patients (30%) and 294 patients (45%) failed to achieve a EULAR and SDAI50 response, respectively. There was a good agreement between EULAR and SDAI50 RMs with a kappa of 0.59 (95% confidence interval 0.53-0.66). Throughout the range of disease activity, the SDAI50 response was shown to be more stringent than the EULAR response. Multivariable linear regression analysis demonstrated that both RMs at 3 months were associated with LDAS or REM at 6 months, and SDAI50 had a more significant impact on this outcome compared to the EULAR response. CONCLUSION: There is a good agreement between the EULAR and SDAI50 RMs. Although a minority of patients have discordant RMs at each end of the disease activity spectrum at baseline, the SDAI50 response at 3 months appears to be a more significant predictor of outcomes at 6 months than EULAR response.

Identifying flares in rheumatoid arthritis: reliability and construct validation of the OMERACT RA Flare Core Domain Set.

OBJECTIVE: To evaluate the reliability of concurrent flare identification using 3 methods (patient, rheumatologist and Disease Activity Score (DAS)28 criteria), and construct validity of candidate items representing the Outcome Measures in Rheumatology Clinical Trials (OMERACT) RA Flare Core Domain Set. METHODS: Candidate flare questions and legacy measures were administered at consecutive visits to Canadian Early Arthritis Cohort (CATCH) patients between November 2011 and November 2014. The American College of Rheumatology (ACR) core set indicators were recorded. Concordance to identify flares was assessed using the agreement coefficient. Construct validity of flare questions was examined: convergent (Spearman's r); discriminant (mean differences between flaring/non-flaring patients); and consequential (proportions with prior treatment reductions and intended therapeutic change postflare). RESULTS: The 849 patients were 75% female, 81% white, 42% were in remission/low disease activity (R/LDA), and 16-32% were flaring at the second visit. Agreement of flare status was low-strong (κ's 0.17-0.88) and inversely related to RA disease activity level. Flare domains correlated highly (r's≥0.70) with each other, patient global (r's≥0.66) and corresponding measures (r's 0.49-0.92); and moderately highly with MD and patient-reported joint counts (r's 0.29-0.62). When MD/patients agreed the patient was flaring, mean flare domain between-group differences were 2.1-3.0; 36% had treatment reductions prior to flare, with escalation planned in 61%. CONCLUSIONS: Flares are common in rheumatoid arthritis (RA) and are often preceded by treatment reductions. Patient/MD/DAS agreement of flare status is highest in patients worsening from R/LDA. OMERACT RA flare questions can discriminate between patients with/without flare and have strong evidence of construct and consequential validity. Ongoing work will identify optimal scoring and cut points to identify RA flares.

The comparative effectiveness of oral versus subcutaneous methotrexate for the treatment of early rheumatoid arthritis.

OBJECTIVE: To determine the comparative effectiveness of oral versus subcutaneous methotrexate (MTX) as initial therapy for patients with early rheumatoid arthritis (ERA). METHODS: Patients with ERA (symptoms ≤1 year) initiating MTX therapy were included from a multicentre, prospective cohort study. We compared the effectiveness between starting with oral versus subcutaneous MTX over the first year. Longitudinal multivariable models, adjusted for potential baseline and time-varying confounders, were used to compare treatment changes due to inefficacy or toxicity and treatment efficacy (Disease Activity Score-28 (DAS-28), DAS-28 remission and Health Assessment Questionnaire-Disability Index (HAQ-DI)). RESULTS: 666 patients were included (417 oral MTX, 249 subcutaneous MTX). Patients prescribed subcutaneous MTX were prescribed a higher dose of MTX (mean dose over first three months 22.3 mg vs 17.2 mg/week). At 1 year, 49% of patients initially treated with subcutaneous MTX had changed treatment compared with 77% treated with oral MTX. After adjusting for potential confounders, subcutaneous MTX was associated with a lower rate of treatment failure ((HR (95% CI) 0.55 (0.39 to 0.79)). Most treatment failures were due to inefficacy with no difference in failure due to toxicity. In multivariable models, subcutaneous MTX was also associated with lower average DAS-28 scores (mean difference (-0.38 (95% CI -0.64 to -0.10)) and a small difference in DAS-28 remission (OR 1.2 (95% CI 1.1 to 1.3)). There was no significant difference in sustained remission or HAQ-DI (p values 0.43 and 0.75). CONCLUSIONS: Initial treatment with subcutaneous MTX was associated with lower rates of treatment changes, no difference in toxicity and some improvements in disease control versus oral MTX over the first year in patients with ERA.

Attitudes towards subsequent entry biologics/biosimilars: A survey of Canadian rheumatologists.

Globally, patents on several well established biologic agents used to treat rheumatic diseases have already or will expire over the next few years, allowing for the availability of subsequent entry biologics (SEBs or biosimilars). The objective of this study was to identify gaps in knowledge and attitudes towards SEBs among Canadian rheumatologists. Eighty-one rheumatologists completed the survey and were included in the analysis (22 % of the 369 who were contacted). We found that one third of physicians (31 %) were familiar with SEBs and that physicians with greater than 20 years of practice were significantly more likely to be familiar or very familiar with SEBs compared to respondents with less than 10 years or 10-20 years of experience (OR 11.1, 95 % CI: 2.1-55.5, p = 0.004 and OR 4.5, 95 % CI: 1.2-16.2, p = 0.023, respectively). A third (32 %) of physicians agreed or strongly agreed that they would be comfortable with indication extrapolation. Most respondents (88 %) would feel concerned or very concerned if a pharmacist had the ability to substitute a biologic drug for an SEB without the physician's approval. This survey was the first study that evaluated the position of rheumatologists on key areas surrounding SEBs from a nationwide Canadian perspective. Current physician attitudes and perceptions of SEBs can inform future educational initiatives and highlight important issues for payers, policy makers, and other stakeholders.