Predictor Of Structural Damage Research Articles

Methods of Assessing the Damage Capacity of Input Seismic Motions for Underground Structures

This paper investigates a method for improving the selection of seismic motions for designing earthquake-resistant underground structures. It is found that PGV alone is unreliable as a predictor of structural damage with increasing earthquake intensity. Therefore, based on characterizing seismic intensity by using PGV, another parameter, referred to here as “the severest parameter”, is introduced to distinguish potential damage capacity for different seismic motions. A numerical model of a soil–underground structure system was established using the finite element software OpenSees. A total of 120 real ground motions were selected for the model, considering the influences of eight different site groups on the underground station and the rupture distances of the input seismic motions. The results show that as seismic intensity increases, substantial variability in the response of underground structures emerges under the same amplitude of PGV, diminishing the effectiveness of the relationship between PGV and structural damage. When assessing the potential damage capacity of seismic motions with similar or close amplitudes of PGV, VSI is an appropriate severest parameter for Class III sites and ASI is suitable for Class II sites. When the correlation coefficient between the severest parameter and the structural response is greater than 0.8, it can be used to reliably assess seismic damage capacity based on the size of the severest parameter.

Proceedings of the 2020 GRAPPA Collaborative Research Network (CRN) Meeting.

At the 2020 Group for Research and Assessment of Psoriasis and Psoriatic Arthritis (GRAPPA)- Collaborative Research Network (CRN) annual meeting, the GRAPPA-CRN group presented a pilot investigator-initiated study protocol to test electronic case report forms (eCRFs) and proposed Standardized Operating Procedures (SOPs) to evaluate biomarkers of psoriatic arthritis (PsA) associated with axial disease. The progress on 3 studies was also presented: BioDAM PsA (Biomarkers as Predictors of structural DAMage in PsA; to validate soluble biomarkers as predictors of structural damage in PsA), PreventPsA (examining the development of PsA and risk factors among patients with psoriasis and no arthritis), and PredictORPsA (Predicting Treatment respOnse in patients with eaRly PsA; in collaboration with Pfizer using samples from the Oral Psoriatic Arthritis TriaL [OPAL], to identify biomarkers of treatment response). GRAPPA-CRN funding partnerships and applications are also underway with both the Innovative Medicines Initiative (IMI) in Europe and Accelerating Medicines Partnerships (AMP) 2.0 in the USA, and the progress of these applications and associated objectives were presented.

Proceedings of the 2017 GRAPPA Collaborative Research Network Meeting.

The Group for Research and Assessment of Psoriasis and Psoriatic Arthritis (GRAPPA) Collaborative Research Network (CRN) is an endeavor that aims to address gaps in the knowledge of the etiopathogenesis and management of psoriatic disease by best using the large community of experienced investigators who are already collecting rich clinical phenotype data and biologic samples using validated techniques. Exemplar rheumatology and dermatology projects will inform strategies to implement the CRN, while input and funding from government organizations, charities, and industry will shape the CRN. The key immediate priorities to establish the CRN are discussed herein and include (1) strategies for building infrastructure to collect and store biosamples and associated clinical data, (2) best practices for sample collection and storage, (3) approaches to engage the GRAPPA community of investigators and industry to collaborate most effectively on shared priorities, and (4) agreement on a funding strategy. The following 4 CRN candidate flagship research areas were identified: (1) predictors of treatment response in psoriatic arthritis (PsA) and cutaneous psoriasis (PsC) to permit personalized and stratified medicine approaches; (2) predictors of structural damage and disease severity, linking with the existing PsA BioDAM project; (3) predictors of PsC progressing to PsA to enable earlier intervention and possibly halt progression to PsA; and (4) comorbidity prevalence and effect on clinical outcomes in psoriatic disease. The collaboration and momentum provided by a GRAPPA-CRN will offer more than the sum of its individual contributing centers. A CRN will permit high-quality research that can more effectively address questions pertinent to patients, clinicians, scientists, industry, and governments.

Hand bone loss in early rheumatoid arthritis during a methotrexate-based treat-to-target strategy with or without adalimumab—a substudy of the optimized treatment algorithm in early RA (OPERA) trial

This study aims to investigate 1-year hand bone loss (HBL1-year) in early rheumatoid arthritis (RA) patients treated with a methotrexate (MTX) and intra-articular triamcinolone treat-to-target strategy +/- adalimumab and to determine if HBL6months is associated with radiographic progression after 2years. In a clinical trial (OPERA) of 180 treatment-naive early RA patients, bone mineral density (BMD) was estimated from hand radiographs with digital X-ray radiogrammetry (DXR) at baseline, after 6 (n=90) and 12months (n=70) of follow-up. Baseline and 2-year radiographs were scored according to the Sharp/van der Heijde method. Baseline characteristics and HBL6months (0-6months changes in DXR-BMD) were investigated as predictors of structural damage by univariate linear (∆ total Sharp/van der Heijde score (TSS) as dependent variable) and logistic (+/-radiographic progression (∆TSS >0) as dependent variable) regression analyses. Variables with p<0.10 were included in multivariable models. In 70 patients with available HBL1-year data, HBL1-year was median (interquartile range (IQR)) -1.9 (-3.3; -0.26mg/cm2) in the MTX + placebo group and -1.8 (-3.6; 0.06)mg/cm2 in the MTX + adalimumab group, p=0.98, Wilcoxon signed-rank. Increased HBL (compared to general population reference values) was found in 26/37 and 23/33 patients in the MTX + placebo and MTX + adalimumab groups, chi-squared=0.99. In 90 patients with HBL6months data and 2-year radiographic data, HBL6months was independently associated with ∆TSS after 2years (β=-0.086 (95% confidence interval=-0.15; -0.025) TSS unit/mg/cm2 increase, p=0.006) but not with presence of radiographic progression (∆TSS >0) (OR 0.96 (0.92-1.0), p=0.10). In early RA patients treated with a methotrexate-based treat-to-target strategy, the majority of patients had increased HBL1-year, irrespective of adalimumab; HBL6months was independently associated with ∆TSS after 2years.

Self-reported flares are predictors of radiographic progression in rheumatoid arthritis patients in 28-joint disease activity score remission: a 24-month observational study.

BackgroundDisease flares are common in rheumatoid arthritis (RA) and are related to structural damage. However, few data on the impact of flares reported by patients on radiographic progression are available. Our aim was to investigate whether overall flares (OF), self-reported flares (SRF) and short flares assessed at the visit (SF) predict radiographic progression in RA patients in DAS28 (28-joint disease activity score) remission.MethodsWe reviewed the records of RA patients included in our database. We considered all patients who had a period of at least 24 months in remission (DAS28 < 2.6), stable biologic and synthetic disease-modifying anti-rheumatic drug treatment, no missing follow-up visits and hands and feet radiographs at the start and at the end of the 24-month follow up. Radiographic progression was considered as an increase in the van der Heijde modified total Sharp score >0. Patients were assessed every 3 months and flares were recorded. We defined SRF as any worsening of the disease reported by patients occurring in the time between visits and SF as an increase in DAS28 ≥ 2.6 or >0.6 from the previous visit assessed by the physician in one isolated visit. The impact of SRF, SF and OF on radiographic progression was assessed through multivariate regression analysis.ResultsOne hundred forty-nine patients were included. The median number (interquartile range) of OF was 1.00/year (0.50; 1.38), of SRF was 0.50/year (0.14; 1.00), and of SF was 0.34/year (0; 0.50). Eighteen patients (12.1 %) experienced a progression of radiographic damage. OF and SRF were significant predictors of radiographic progression: OR 3.27, 95 % CI 1.30, 8.22 and OR 3.63, 95 % CI 1.16, 11.36, respectively.ConclusionsOF and SRF are predictors of structural damage. Flares assessed at the visit, SF, do not impact on radiographic progression as they might underestimate the actual number of flares.Electronic supplementary materialThe online version of this article (doi:10.1186/s13075-016-0986-1) contains supplementary material, which is available to authorized users.