65 research outputs found
The Legal Environment and the Choice of Default Resolution Alternatives: An Empirical Analysis
In addition to standard foreclosure, three other methods of resolution for mortgage defaults are available: bankruptcy protection, surrender of deed to the lender, and pre-foreclosure sale. This paper develops a model that specifies the choice of resolution method as a function of the state-specific legal environment and local area economic conditions. A large national data set is used to estimate a multinomial logit choice model for the 1987 to 1991 period. The results indicate that the choice of default resolution alternative is sensitive to the legal environment. The results imply that selected legal reforms will tend to improve the efficiency of the default resolution process.
The Effect of Relative Pricing on the Fixed-Rate Mortgage Term Decision
This paper analyzes determinants of the fifteen- versus thirty-year fixed-rate mortgage (FRM) loan term decision. Because the thirty-year FRM may be converted (by partial prepayment) to the shorter term, the thirty-year instrument provides the implicit option to extend repayment. Relative rates measure the price (cost) of this option to the consumer. The results indicate that the term decision of consumers is highly sensitive to relative rates: probit estimates using data from a large national lending institution for the 1987 to 1990 period indicate that a 1% increase in the ratio of fifteen- to thirty-year rates lowers the probability of fifteen-year term choice by 20%. The results also indicate that expected housing price appreciation, which measures investment determinants of housing demand, is negatively related to the fifteen-year FRM term choice.
Laser-annealing Josephson junctions for yielding scaled-up superconducting quantum processors
As superconducting quantum circuits scale to larger sizes, the problem of
frequency crowding proves a formidable task. Here we present a solution for
this problem in fixed-frequency qubit architectures. By systematically
adjusting qubit frequencies post-fabrication, we show a nearly ten-fold
improvement in the precision of setting qubit frequencies. To assess
scalability, we identify the types of 'frequency collisions' that will impair a
transmon qubit and cross-resonance gate architecture. Using statistical
modeling, we compute the probability of evading all such conditions, as a
function of qubit frequency precision. We find that without post-fabrication
tuning, the probability of finding a workable lattice quickly approaches 0.
However with the demonstrated precisions it is possible to find collision-free
lattices with favorable yield. These techniques and models are currently
employed in available quantum systems and will be indispensable as systems
continue to scale to larger sizes.Comment: 9 pages, 6 figures, Supplementary Information. Update to correct typo
in author name and in text. Updated acknowledgements and corrected typo in
acknowledgement
The ANTENATAL multicentre study to predict postnatal renal outcome in fetuses with posterior urethral valves: objectives and design
Abstract
Background
Posterior urethral valves (PUV) account for 17% of paediatric end-stage renal disease. A major issue in the management of PUV is prenatal prediction of postnatal renal function. Fetal ultrasound and fetal urine biochemistry are currently employed for this prediction, but clearly lack precision. We previously developed a fetal urine peptide signature that predicted in utero with high precision postnatal renal function in fetuses with PUV. We describe here the objectives and design of the prospective international multicentre ANTENATAL (multicentre validation of a fetal urine peptidome-based classifier to predict postnatal renal function in posterior urethral valves) study, set up to validate this fetal urine peptide signature.
Methods
Participants will be PUV pregnancies enrolled from 2017 to 2021 and followed up until 2023 in >30 European centres endorsed and supported by European reference networks for rare urological disorders (ERN eUROGEN) and rare kidney diseases (ERN ERKNet). The endpoint will be renal/patient survival at 2 years postnatally. Assuming α = 0.05, 1–β = 0.8 and a mean prevalence of severe renal outcome in PUV individuals of 0.35, 400 patients need to be enrolled to validate the previously reported sensitivity and specificity of the peptide signature.
Results
In this largest multicentre study of antenatally detected PUV, we anticipate bringing a novel tool to the clinic. Based on urinary peptides and potentially amended in the future with additional omics traits, this tool will be able to precisely quantify postnatal renal survival in PUV pregnancies. The main limitation of the employed approach is the need for specialized equipment.
Conclusions
Accurate risk assessment in the prenatal period should strongly improve the management of fetuses with PUV
Clinical and molecular heterogeneity in patients with the cblD inborn error of cobalamin metabolism
OBJECTIVES: To describe 3 patients with the cblD disorder, a rare inborn error of cobalamin metabolism caused by mutations in the MMADHC gene that can result in isolated homocystinuria, isolated methylmalonic aciduria, or combined homocystinuria and methylmalonic aciduria. STUDY DESIGN: Patient clinical records were reviewed. Biochemical and somatic cell genetic studies were performed on cultured fibroblasts. Sequence analysis of the MMADHC gene was performed on patient DNA. RESULTS: Patient 1 presented with isolated methylmalonic aciduria, patient 3 with isolated homocystinuria, and patient 2 with combined methylmalonic aciduria and homocystinuria. Studies of cultured fibroblasts confirmed decreased synthesis of adenosylcobalamin in patient 1, decreased synthesis of methylcobalamin in patient 3, and decreased synthesis of both cobalamin derivatives in patient 2. The diagnosis of cblD was established in each patient by complementation analysis. Mutations in the MMADHC gene were identified in all patients. CONCLUSIONS: The results emphasize the heterogeneous clinical, cellular and molecular phenotype of the cblD disorder. The results of molecular analysis of the MMADHC gene are consistent with the hypothesis that mutations affecting the N terminus of the MMADHC protein are associated with methylmalonic aciduria, and mutations affecting the C terminus are associated with homocystinuria
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