4,195 research outputs found
Corruption in bank lending to firms : do competition and information sharing matter?
Building on the important study by Beck, Demirguc-Kunt and Levine (2006), we examine the effects of borrower and lender competition and information sharing νia credit registries/bureaus on corruption in bank lending. Using the unique World Bank dataset of the World Business Environment Survey (WBES) covering 58 countries and information on credit registries/bureaus and bank regulation assembled by other scholars, we find (1) strong evidence that banking competition reduces lending corruption and (2) the first and robust evidence that information sharing among banks (especially via private bureaus) contributes to reducing corruption in bank lending. We also find that government- and foreign-owned firms as well as exporting firms tend to be subject to less lending corruption, objective courts and better law enforcement tend to reduce lending corruption, and private and foreign ownership of the banking industry are associated with more integrity in lending. These findings pass a number of robustness tests and they are consistent with the predictions of a Nash bargaining model
A new family-based association test via a least-squares method
To test the association between a dichotomous phenotype and genetic marker based on family data, we propose a least-squares method using the vector of phenotypes and their cross products within each family. This new approach allows covariate adjustment and is numerically much simpler to implement compared to likelihood- based methods. The new approach is asymptotically equivalent to the generalized estimating equation approach with a diagonal working covariance matrix, thus avoiding some difficulties with the working covariance matrix reported previously in the literature. When applied to the data from Collaborative Study on the Genetics of Alcoholism, this new method shows a significant association between the marker rs1037475 and alcoholism
The influence of water immersion on the mechanical property of cement asphalt mortar and its implications on the slab track
Dynamic compression test of cement asphalt (CA) mortar specimens, due to water immersion history of 0d, 7d, 14d and 30d, are carried out using a universal electronic test machine, with the strain rates ranging from 1×10-5 s-1 to 1×10-2 s-1. The stress-strain full curves, the compressive strength and the elastic modulus of CA mortar at different strain rates and water immersion durations are analyzed and the effects of strain rates and water immersion duration on these behaviors are studied. Experimental results demonstrate that the compressive strength and elastic modulus increase with the strain rate. In the same strain rate, the compressive strength decreases with the increase of water immersion duration, but the elastic modulus decrease first and then increase with the increase of water immersion duration. The largest reduction of average compressive strength of CA mortar is 46.5 %, and the largest reduction in the average elastic modulus of CA mortar is 47.5 %. A vertical coupling vibration model for a vehicle-railway track-subgrade system was established on the base of wheel-rail coupling dynamics theory and experimental results. The effects of elastic modulus deterioration of CA mortar on the dynamic responses of the vehicle and railway track system were studied. The results show that the reduction of CA mortar has little influence on the dynamic properties of the track and the running stability
An energy stable C<sup>0</sup> finite element scheme for a quasi-incompressible phase-field model of moving contact line with variable density
In this paper, we focus on modeling and simulation of two-phase flow with
moving contact lines and variable density. A thermodynamically consistent
phase-field model with General Navier Boundary Condition is developed based on
the concept of quasi-incompressibility and the energy variational method. Then
a mass conserving and energy stable C0 finite element scheme is developed to
solve the PDE system. Various numerical simulation results show that the
proposed schemes are mass conservative, energy stable and the 2nd order for P1
element and 3rd order for P2 element convergence rate in the sense of L2 norm
Non-saturating large magnetoresistance in semimetals
The rapidly expanding class of quantum materials known as {\emph{topological
semimetals}} (TSM) display unique transport properties, including a striking
dependence of resistivity on applied magnetic field, that are of great interest
for both scientific and technological reasons. However, experimental signatures
that can identify or discern the dominant mechanism and connect to available
theories are scarce. Here we present the magnetic susceptibility (), the
tangent of the Hall angle () along with magnetoresistance in four
different non-magnetic semimetals with high mobilities, NbP, TaP, NbSb and
TaSb, all of which exhibit non-saturating large MR. We find that the
distinctly different temperature dependences, and the values of
in phosphides and antimonates serve as empirical criteria to
sort the MR from different origins: NbP and TaP being uncompensated semimetals
with linear dispersion, in which the non-saturating magnetoresistance arises
due to guiding center motion, while NbSb and TaSb being {\it
compensated} semimetals, with a magnetoresistance emerging from nearly perfect
charge compensation of two quadratic bands. Our results illustrate how a
combination of magnetotransport and susceptibility measurements may be used to
categorize the increasingly ubiquitous non-saturating large magnetoresistance
in TSMs.Comment: Accepted for publication at Proc. Natl. Acad. Sci., minor revisions,
6 figure
Suppression of Superconductivity by Twin Boundaries in FeSe
Low-temperature scanning tunneling microscopy and spectroscopy are employed
to investigate twin boundaries in stoichiometric FeSe films grown by molecular
beam epitaxy. Twin boundaries can be unambiguously identified by imaging the
90{\deg} change in the orientation of local electronic dimers from Fe site
impurities on either side. Twin boundaries run at approximately 45{\deg} to the
Fe-Fe bond directions, and noticeably suppress the superconducting gap, in
contrast with the recent experimental and theoretical findings in other iron
pnictides. Furthermore, vortices appear to accumulate on twin boundaries,
consistent with the degraded superconductivity there. The variation in
superconductivity is likely caused by the increased Se height in the vicinity
of twin boundaries, providing the first local evidence for the importance of
this height to the mechanism of superconductivity.Comment: 6 pages, 7 figure
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