23 research outputs found
Development and Manufacture of the Coil End Spacers of the LHC Pre-series Dipoles
The coil end spacers play an important role in the performance of superconducting coils, as their shape and location determine the mechanical stability of the conductors in the coil ends (and hence the overall coil training performance) and the local field quality. The dipole end spacers are often of a size and a geometry difficult to be industrially series manufactured and measured. Efficiency of the production and related costs are a key issue to achieve the required production rate of the LHC main dipoles at an affordable price. For the latter reasons, a design approach integrating state-of-the-art CAD/CAM optimization techniques allowing to considerably decrease design and machining time was implemented. This paper gives examples and describes the design criteria, the computation methods, the machining and measuring procedures adopted to carry out the pre-series production
Field quality in the ends of the Large Hadron Collider main dipole: Measurements and correlation to industrial assembly procedures
Magnetic field measurements are an important tool to monitor the LHC main dipole production. In this paper we analyse the data relative to a few tens of collared coils produced for the pre-series dipoles. Strong systematic differences between field at the magnet extremities are observed. Moreover, three different families of coil ends corresponding to the different coil manufacturers can be singled out. A 3D model of the coil ends is used to understand these differences in terms of the assembly parameters and the industrial procedures. We analyse the production trends in order to characterize the geometric parameters and the critical components for the field quality. The field components in the dipole ends are finally compared to the beam dynamics budget allowed for the whole dipole
A prediction rule for lack of achievement of inactive disease with methotrexate as the sole disease-modifying antirheumatic therapy in juvenile idiopathic arthritis
Background: To investigate the frequency of achievement of inactive disease (ID) in children with juvenile idiopathic arthritis (JIA) treated with methotrexate (MTX) as the sole disease-modifyng antirheumatic (DMARD) therapy and to develop a prediction model for lack of attainment of ID. Methods: The clinical charts of consecutive patients started with MTX as the sole DMARD between 2000 and 2013 were reviewed. Patient follow-up was censored at first episode of ID or, in case ID was not reached, at last follow-up visit or when a biologic DMARD was prescribed. The characteristic at MTX start of patients who achieved or did not achieve ID were compared with univariate and multivariable analyses. Regression coefficients (\u3b2) of variables that entered the best-fitting logistic regression model were converted and summed to obtain a "prediction score" for lack of achievement of ID. Results: A total of 375 patients were included in the study. During MTX administration, 8.8% were given systemic corticosteroids and 44.1% intra-articular corticosteroids. After MTX start, 229 (61%) patients achieved ID after a median of 1.7 years, whereas 146 patients (39%) did not reach ID after a median of 1.2 years. On multivariable analysis, independent correlations with lack of achievement of ID were identified for the disease categories of systemic arthritis, enthesitis-related arthritis (ERA) and polyarthritis and C-reactive protein (CRP) > 1.4 mg/dl. The prediction score ranged from 0 to 3 and its cutoff that discriminated best between patients who achieved or did not achieve ID was > 0.5. The categories of systemic arthritis or ERA, both of which had a score greater than 0.5, were sufficient alone to predict a lower likelihood to reach ID. Polyarthritis and increased CRP, whose score was 0.5, assumed a predictive value only when present in association. Conclusion: A conventional treatment regimen based on MTX as the sole DMARD led to achievement of ID in a sizeable proportion of children with JIA. Our findings help to outline the characteristics of patients who may deserve a synthetic DMARD other than MTX or the introduction of a biologic DMARD from disease outset
Analisi elettromagnetica tridimensionale delle teste delle bobine nel dipolo principale di LHC
The spacers placed at coil ends play an important role in the performance of superconducting coils, as their shape and location determine the mechanical stability of the conductors in the coil ends and the local field quality. The dipole end spacers are critical components due to their size and geometry, and they are difficult to be industrially series manufactured. In order to achieve the required production rate of the LHC main dipoles at an affordable price both the design, the production and the control have to be optimized. In this prospective a 3D model was created to reproduce the electromagnetic behavior of the dipole heads. Thanks to this tool it was possible to create a sensitivity map able to describe the effect of a geometric variation in the end spacers on the local field quality. A similar analysis was carried out to point out the geometric parameters critical for the quench performances of the magnet
Architettura militare e paesaggio tra storia, conservazione e riuso
Following the D.L. n. 85/2010 on the federal state property and in agreement with the MIBACT, the Genoa\u2019s Fortifications System entered theavailability of the Municipality of Genoa which is looking for shared solutions to the conservation and enhancement of this unique heritage. It is an architectural and territorial system of high landscape value formed by walls and fortifications built between the seventeenth and nineteenth century. Quezzi tower, the last still intact of twelve circular towers isolated in the Genoa\u2019s military fortifications, built in the nineteenth century, nowadays is in ruin state of conservation. The adopted criteria aimed to the enhancement and conservation of this original building, lay down the foundations for a larger redevelopment project of all the Genoa\u2019s fortifications system on the height of the city
Parent and child acceptable symptom state in juvenile idiopathic arthritis.
To explore the parent and child acceptable symptom state in juvenile arthritis (JA-PASS and JA-CASS, respectively) and estimate the JA-PASS and JA-CASS cutoff values for outcome measures.Children with juvenile idiopathic arthritis (JIA) and their parents completed a multi-dimensional questionnaire that included parent-reported and child-reported outcomes and a question about whether they considered the disease state as satisfactory. Additional assessments included demographic data, physician-reported outcomes, and acute-phase reactant levels. Stepwise logistic regression was used to assess contributors to JA-PASS and JA-CASS. Cutoff values of outcome measures that defined JA-PASS and JA-CASS were determined using both 75th percentile and receiver-operating characteristic (ROC) curve methods. Testing procedures included evaluation of discriminative and construct validity of the satisfaction question and assessment of reliability of JA-PASS and JA-PASS cutoffs.Of 584 parents, 385 (65.9\%) considered their child in JA-PASS. Of 343 children, 236 (68.8\%) considered themselves in JA-CASS. Significant contributors to being in either JA-PASS or JA-CASS were absence of active joints, better rating of overall well-being, and better physical function or health. Cutoff values yielded by 75th percentile and ROC curve methods were similar. Parent, child, and physician global ratings yielded the lowest percentage of false-positive misclassification and the best tradeoff between sensitivity and specificity. The satisfaction question showed good discriminative and construct validity and the JA-PASS and JA-PASS cutoffs were found to be stable over time.The acceptable symptom state is a relevant concept for children with JIA and their parents and constitutes a valid outcome measure that is potentially applicable in routine practice and clinical trials