555 research outputs found
Design and Assembly of a Large-aperture Nb3Sn Cos-theta Dipole Coil with Stress Management in Dipole Mirror Configuration
The stress-management cos-theta (SMCT) coil is a new concept which has been
proposed and is being developed at Fermilab in the framework of US Magnet
Development Program (US-MDP) for high-field and/or large-aperture accelerator
magnets based on low-temperature and high-temperature superconductors. The SMCT
structure is used to reduce large coil deformations under the Lorentz forces
and, thus, the excessively large strains and stresses in the coil. A
large-aperture Nb3Sn SMCT dipole coil has been developed and fabricated at
Fermilab to demonstrate and test the SMCT concept including coil design,
fabrication technology and performance. The first SMCT coil has been assembled
with 60-mm aperture Nb3Sn coil inside a dipole mirror configuration and will be
tested separately and in series with the insert coil. This paper summarizes the
large-aperture SMCT coil design and parameters and reports the coil fabrication
steps and its assembly in dipole mirror configuration
Self-Field Effects in Magneto-Thermal Instabilities for Nb-Sn Strands
Recent advancements in the critical current density (Jc) of NbSn conductors, coupled with a large effective filament size, have drawn attention to the problem of magnetothermal instabilities. At low magnetic fields, the quench current of such high Jc NbSn strands is significantly lower than their critical current because of the above-mentioned instabilities. An adiabatic model to calculate the minimum current at which a strand can quench due to magneto-thermal instabilities is developed. The model is based on an 'integral' approach already used elsewhere [1]. The main difference with respect to the previous model is the addition of the self-field effect that allows to describe premature quenches of non-magnetized NbSn strands and to better calculate the quench current of strongly magnetized strands. The model is in good agreement with experimental results at 4.2 K obtained at Fermilab using virgin Modified Jelly Roll (MJR) strands with a low Residual Resistivity Ratio (RRR) of the stabilizing copper. The prediction of the model at 1.9 K and the results of the tests carried out at CERN, at 4.2 K and 1.9 K, on a 0.8 mm Rod Re-Stack Process (RRP) strand with a low RRR value are discussed. At 1.9 K the test revealed an unexpected strand performance at low fields that might be a sign of a new stability regime
Assessing the Association between Serum Ferritin, Transferrin Saturation, and C-Reactive Protein in Northern Territory Indigenous Australian Patients with High Serum Ferritin on Maintenance Haemodialysis
Copyright © 2017 SandawanaWilliam Majoni et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.Objective. To determine the significance of high serum ferritin observed in Indigenous Australian patients on maintenance haemodialysis in the Northern Territory, we assessed the relationship between ferritin and transferrin saturation (TSAT) as measures of iron status and ferritin and C-reactive protein (CRP) as markers of inflammation. Methods. We performed a retrospective cohort analysis of data from adult patients (≥18 years) on maintenance haemodialysis (>3 months) from 2004 to 2011. Results. There were 1568 patients. The mean age was 53.9 (11.9) years. 1244 (79.3%) were Indigenous. 44.2% () were male. Indigenous patients were younger (mean age [52.3 (11.1) versus 57.4 (15.2), ]) and had higher CRP [14.7 mg/l (7–35) versus 5.9 mg/l (1.9–17.5), ], higher median serum ferritin [1069 µg/l (668–1522) versus 794.9 µg/l (558.5–1252.0), ], but similar transferrin saturation [26% (19–37) versus 28% (20–38), ]. We observed a small positive correlation between ferritin and TSAT (, ), no correlation between ferritin and CRP ( = 0.001, ), and positive association between high serum ferritin and TSAT (), Indigenous ethnicity (), urea reduction ratio (), and gender () after adjustment in mixed regression analysis. Conclusion. Serum ferritin and TSAT may inadequately reflect iron status in this population. The high ferritin was poorly explained by inflammation
High Energy & High Luminosity Colliders
With the best of modern standard lasers, high-energy colliders
from electron beams of E larger than 250 GeV are only possible at the expense
of photon luminosity, i.e. 10 times lower than for photon colliders at c.m.
energies below 0.5 TeV. For existing state-of-the art lasers, an optimistic
upper energy limit for x=4.8 is an electron beam of less than 250 GeV. This
Snowmass21 Contributed Paper shows how Free Electron Lasers (FEL) pave the way
for High Energy & High Luminosity colliders. We present and
assess a conceptual design study of a FEL with wavelength of 2.4 m and an
x-factor in the range of 2 to 40, to maximize the luminosity of a
collider as second interaction region of 0.5 TeV to 10 TeV c.m.
colliders.Comment: Contribution to Snowmass 202
Long-term outcome of patients with transposition of the great arteries and a systemic right ventricle:A systematic review and meta-analysis
BACKGROUND: Patients with a transposition of the great arteries (TGA) and a systemic right ventricle are at risk of heart failure (HF) development, arrhythmia and early mortality. Prognostic evaluations in clinical studies are hampered by small sample sizes and single-centred approaches. We aimed to investigate yearly rate of outcome and factors affecting it.METHODS: A systematic literature search of four electronic databases (PubMed, EMBASE, Web of Science and Scopus) was conducted from inception to June 2022. Studies reporting the association of a systemic right ventricle with mortality with a minimal follow-up of 2 years during adulthood were selected. Incidence of HF hospitalization and/or arrhythmia were captured as additional endpoints. For each outcome, a summary effect estimate was calculated.RESULTS: From a total of 3891 identified records, 56 studies met the selection criteria. These studies described the follow-up (on average 7.27 years) of 5358 systemic right ventricle patients. The mortality incidence was 1.3 (1-1.7) per 100 patients/year. The incidence of HF hospitalization was 2.6 (1.9-3.7) per 100 patients/year. Predictors of poor outcome were a lower left ventricular (LV) and right ventricular ejection fraction (RVEF) (standardized mean differences (SMD) of -0.43 (-0.77 to -0.09) and - 0.85 (-1.35 to -0.35), respectively), higher plasma concentrations of NT-proBNP (SMD of 1.24 (0.49-1.99)), and NYHA class ≥2 (risk ratio of 2.17 (1.40-3.35)).CONCLUSIONS: TGA patients with a systemic right ventricle have increased incidence of mortality and HF hospitalization. A lower LVEF and RVEF, higher levels of NT-proBNP and NYHA class ≥2 are associated with poor outcome.</p
Linear and profilometric changes of the mucosa following soft tissue augmentation in the zone of aesthetic priority:A systematic review and meta-analysis
OBJECTIVES: To assess the outcomes of soft tissue augmentation, in terms of change in level and thickness of mid-buccal mucosa, at implants sites in the zone of the aesthetic priority. MATERIAL AND METHODS: MEDLINE, EMBASE and Cochrane Central Register of Controlled Trials databases were searched (last search on 1 June 2020). Inclusion criteria were studies reporting outcomes of different materials and timing of grafting in patients undergoing soft tissue augmentation at implant sites in the aesthetic zone with a follow-up of ≥1 year after implant placement. Outcome measures assessed included changes in level and thickness of mid-buccal mucosa, implant survival, peri-implant health and patients' satisfaction. RESULTS: Eighteen out of 2,185 articles fulfilled the inclusion criteria. Meta-analysis revealed a significant difference in vertical mid-buccal soft tissue change (0.34 mm, 95% CI: 0.13-0.56, p = .002) and mid-buccal mucosa thickness (0.66 mm, 95% CI: 0.35-0.97, p < .001) following immediate implant placement in favour of the use of a graft versus no graft. Mean difference in mid-buccal mucosa level following delayed implant placement (0.17 mm, 95% CI: 0.01-0.34, p = .042) was also in favour of the use of a graft versus no graft. With regard to mucosa thickness, the use of a graft was not in favour compared with no graft following delayed implant placement (0.22 mm, 95% CI: -0.04-0.47, p = .095). Observed changes remained stable in the medium term. CONCLUSION: Soft tissue augmentation in the zone of the aesthetic priority results in less recession and a thicker mid-buccal mucosa following immediate implant placement and less recession in mid-buccal mucosa following delayed implant placement compared with no graft
Long-term outcome of patients with transposition of the great arteries and a systemic right ventricle:A systematic review and meta-analysis
BACKGROUND: Patients with a transposition of the great arteries (TGA) and a systemic right ventricle are at risk of heart failure (HF) development, arrhythmia and early mortality. Prognostic evaluations in clinical studies are hampered by small sample sizes and single-centred approaches. We aimed to investigate yearly rate of outcome and factors affecting it.METHODS: A systematic literature search of four electronic databases (PubMed, EMBASE, Web of Science and Scopus) was conducted from inception to June 2022. Studies reporting the association of a systemic right ventricle with mortality with a minimal follow-up of 2 years during adulthood were selected. Incidence of HF hospitalization and/or arrhythmia were captured as additional endpoints. For each outcome, a summary effect estimate was calculated.RESULTS: From a total of 3891 identified records, 56 studies met the selection criteria. These studies described the follow-up (on average 7.27 years) of 5358 systemic right ventricle patients. The mortality incidence was 1.3 (1-1.7) per 100 patients/year. The incidence of HF hospitalization was 2.6 (1.9-3.7) per 100 patients/year. Predictors of poor outcome were a lower left ventricular (LV) and right ventricular ejection fraction (RVEF) (standardized mean differences (SMD) of -0.43 (-0.77 to -0.09) and - 0.85 (-1.35 to -0.35), respectively), higher plasma concentrations of NT-proBNP (SMD of 1.24 (0.49-1.99)), and NYHA class ≥2 (risk ratio of 2.17 (1.40-3.35)).CONCLUSIONS: TGA patients with a systemic right ventricle have increased incidence of mortality and HF hospitalization. A lower LVEF and RVEF, higher levels of NT-proBNP and NYHA class ≥2 are associated with poor outcome.</p
Long-term outcome of patients with transposition of the great arteries and a systemic right ventricle:A systematic review and meta-analysis
BACKGROUND: Patients with a transposition of the great arteries (TGA) and a systemic right ventricle are at risk of heart failure (HF) development, arrhythmia and early mortality. Prognostic evaluations in clinical studies are hampered by small sample sizes and single-centred approaches. We aimed to investigate yearly rate of outcome and factors affecting it.METHODS: A systematic literature search of four electronic databases (PubMed, EMBASE, Web of Science and Scopus) was conducted from inception to June 2022. Studies reporting the association of a systemic right ventricle with mortality with a minimal follow-up of 2 years during adulthood were selected. Incidence of HF hospitalization and/or arrhythmia were captured as additional endpoints. For each outcome, a summary effect estimate was calculated.RESULTS: From a total of 3891 identified records, 56 studies met the selection criteria. These studies described the follow-up (on average 7.27 years) of 5358 systemic right ventricle patients. The mortality incidence was 1.3 (1-1.7) per 100 patients/year. The incidence of HF hospitalization was 2.6 (1.9-3.7) per 100 patients/year. Predictors of poor outcome were a lower left ventricular (LV) and right ventricular ejection fraction (RVEF) (standardized mean differences (SMD) of -0.43 (-0.77 to -0.09) and - 0.85 (-1.35 to -0.35), respectively), higher plasma concentrations of NT-proBNP (SMD of 1.24 (0.49-1.99)), and NYHA class ≥2 (risk ratio of 2.17 (1.40-3.35)).CONCLUSIONS: TGA patients with a systemic right ventricle have increased incidence of mortality and HF hospitalization. A lower LVEF and RVEF, higher levels of NT-proBNP and NYHA class ≥2 are associated with poor outcome.</p
Long-term outcome of patients with transposition of the great arteries and a systemic right ventricle:A systematic review and meta-analysis
BACKGROUND: Patients with a transposition of the great arteries (TGA) and a systemic right ventricle are at risk of heart failure (HF) development, arrhythmia and early mortality. Prognostic evaluations in clinical studies are hampered by small sample sizes and single-centred approaches. We aimed to investigate yearly rate of outcome and factors affecting it.METHODS: A systematic literature search of four electronic databases (PubMed, EMBASE, Web of Science and Scopus) was conducted from inception to June 2022. Studies reporting the association of a systemic right ventricle with mortality with a minimal follow-up of 2 years during adulthood were selected. Incidence of HF hospitalization and/or arrhythmia were captured as additional endpoints. For each outcome, a summary effect estimate was calculated.RESULTS: From a total of 3891 identified records, 56 studies met the selection criteria. These studies described the follow-up (on average 7.27 years) of 5358 systemic right ventricle patients. The mortality incidence was 1.3 (1-1.7) per 100 patients/year. The incidence of HF hospitalization was 2.6 (1.9-3.7) per 100 patients/year. Predictors of poor outcome were a lower left ventricular (LV) and right ventricular ejection fraction (RVEF) (standardized mean differences (SMD) of -0.43 (-0.77 to -0.09) and - 0.85 (-1.35 to -0.35), respectively), higher plasma concentrations of NT-proBNP (SMD of 1.24 (0.49-1.99)), and NYHA class ≥2 (risk ratio of 2.17 (1.40-3.35)).CONCLUSIONS: TGA patients with a systemic right ventricle have increased incidence of mortality and HF hospitalization. A lower LVEF and RVEF, higher levels of NT-proBNP and NYHA class ≥2 are associated with poor outcome.</p
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