8,997 research outputs found
Thrifty Viability and Traditional Mortgage Lending: A Simultaneous Equations Analysis of the Risk-Return Trade-Off
A number of studies have argued that the thrift industry is not viable as it is presently structured and regulated because mortgage yields are inadequate to cover interest and operating costs. This hypothesis suggests that observed profitability is primarily the result of the tendency of the industry to "ride" the yield curve by borrowing short and lending long. To evaluate this argument, we construct a simultaneous-equations model of thrift risk (maturity gap positions) and return (net interest margin). We find support for the notion that the industry could not be reasonably profitable if it did not take on significant interest-rate risk. For instance, a zero gap position produces a return on assets of only 19 basis points and a return on equity of only 4%. We also estimate the amount of interest-rate risk the industry can employ to increase returns on equity and assets. Our estimates show that over 50% of thrift profits earned during this period are the result of negative gap positions and interest-rate speculation. As earlier research shows, changes in regulations affecting thrift asset and liability choices can be counterproductive.
LIGO-Virgo-KAGRA's Oldest Black Holes:Probing Star Formation at Cosmic Noon With GWTC-3
In their third observing run, the LIGO-Virgo-KAGRA gravitational-wave (GW) observatory was sensitive to binary black hole (BBH) mergers out to redshifts zmerge ≈ 1. Because GWs are inefficient at shrinking the binary orbit, some of these BBH systems likely experienced long delay times τ between the formation of their progenitor stars at zform and their GW merger at zmerge. In fact, the distribution of delay times predicted by isolated binary evolution resembles a power law p(τ) ∝ τ ατ with slope −1 ≲ ατ ≲ −0.35 and a minimum delay time of τmin = 10 Myr . We use these predicted delay time distributions to infer the formation redshifts of the ∼70 BBH events reported in the third GW transient catalog GWTC-3 and the formation rate of BBH progenitors. For our default α τ = -1 delay time distribution, we find that GWTC-3 contains at least one system (with 90% credibility) that formed earlier than zform > 4.4. Comparing our inferred BBH progenitor formation rate to the star formation rate, we find that at z form = 4, the number of BBH progenitor systems formed per stellar mass was 6.4+9.4-5.5 × 10−6 M ⊙− 1 and this yield dropped to 0.134+ 1.6-0.127 × 10−6 M⊙−1 by zform = 0. We discuss implications of this measurement for the cosmic metallicity evolution, finding that for typical assumptions about the metallicity dependence of the BBH yield, the average metallicity at zform = 4 was 〈 log 10 (Z/Z⊙ ) 〉= −0 .3+0.3-0.4 , although the inferred metallicity can vary by a factor of ≈3 for different assumptions about the BBH yield. Our results highlight the promise of current GW observatories to probe high-redshift star formation.</p
Monitoring quantity and quality of pangasius pond effluent : report of a monitoring program and recommendations for certification
The quantity and quality of pangasius pond effluent was monitored by means of monthly sampling during a study conducted on four striped catfish farms located in the Mekong Delta, Vietnam. The study was undertaken to test the practical implications of the standards and guidelines with regard to catfish pond effluent that are at present developed by various certification programs for striped catfish production in Vietnam. The results showed a great variability twelve pangasius pond within the samples that were taken during one period of partial pond draining and refilling. The consequences of such variability with regard to the certification standards and guidelines are discussed and recommendations are given
The acoustic contrast between the Dutch consonants /t/ and /d/ is reduced in tracheoesophageal speech
Generating topological order from a 2D cluster state using a duality mapping
In this paper we prove, extend and review possible mappings between the
two-dimensional Cluster state, Wen's model, the two-dimensional Ising chain and
Kitaev's toric code model. We introduce a two-dimensional duality
transformation to map the two-dimensional lattice cluster state into the
topologically-ordered Wen model. Then, we subsequently investigates how this
mapping could be achieved physically, which allows us to discuss the rate at
which a topologically ordered system can be achieved. Next, using a lattice
fermionization method, Wen's model is mapped into a series of one-dimensional
Ising interactions. Considering the boundary terms with this mapping then
reveals how the Ising chains interact with one another. The relationships
discussed in this paper allow us to consider these models from two different
perspectives: From the perspective of condensed matter physics these mappings
allow us to learn more about the relation between the ground state properties
of the four different models, such as their entanglement or topological
structure. On the other hand, we take the duality of these models as a starting
point to address questions related to the universality of their ground states
for quantum computation.Comment: 5 Figure
Detecting and analysing spontaneous oral cancer speech in the wild
Oral cancer speech is a disease which impacts more than half a million people
worldwide every year. Analysis of oral cancer speech has so far focused on read
speech. In this paper, we 1) present and 2) analyse a three-hour long
spontaneous oral cancer speech dataset collected from YouTube. 3) We set
baselines for an oral cancer speech detection task on this dataset. The
analysis of these explainable machine learning baselines shows that sibilants
and stop consonants are the most important indicators for spontaneous oral
cancer speech detection.Comment: Accepted to Interspeech 202
Spin-label EPR Approaches to Protein Interactions
Protein-protein interactions are essential for various biological processes including cell metabolism, muscle contraction, and signal transduction. The dissertation describes a study of the interaction between the proteins cytochrome c and cytochrome c peroxidase by electron paramagnetic resonance spectroscopy (EPR). A spin label containing an unpaired electron was placed at the surface of one of the proteins. The combination of spin labelling and EPR provided novel information on the structure and dynamics of the proteins.Bilogical and Molecular physics - OU
- …