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Financing patterns around the world: Are small firms different?
Using a firm-level survey database covering 48 countries, we investigate how financial and institutional development affects financing of large and small firms. Our database is not limited to large firms but includes small and medium-size firms and data on a broad spectrum of financing sources, including leasing, supplier, development, and informal finance. Small firms and firms in countries with poor institutions use less external finance, especially bank finance. Protection of property rights increases external financing of small firms significantly more than of large firms, mainly due to its effect on bank finance. Small firms do not use disproportionately more leasing or trade finance compared with larger firms, so these financing sources do not compensate for lower access to bank financing of small firms. We also find that larger firms more easily expand external financing when they are constrained than small firms. Finally, we find suggestive evidence that the pecking order holds across countries
A new technique for the reconstruction, validation, and simulation of hits in the CMS Pixel Detector
This note describes new techniques for the reconstruction/validation and the simulation of pixel hits. The techniques are based upon the use of pre-computed projected cluster shapes or ``templates''. A detailed simulation called Pixelav that has successfully described the profiles of clusters measured in beam tests of radiation-damaged sensors is used to generate the templates. Although the reconstruction technique was originally developed to optimally estimate the coordinates of hits after the detector became radiation damaged, it also has superior performance before irradiation. The technique requires a priori knowledge of the track angle which makes it suitable for the second in a two-pass reconstruction algorithm. However, the same modest angle sensitivity allows the algorithm to determine if the sizes and shapes of the cluster projections are consistent with the input angles. This information may be useful in suppressing spurious hits caused by secondary particles and in validating seeds used in track finding. The seed validation is currently under study but has the potential to significantly increase the speed of track finding in the offline reconstruction. Finally, a new procedure that uses the templates to re-weight clusters generated by the CMSSW simulation is described. The first tests of this technique are encouraging and when fully implemented, the technique will enable the fast simulation of pixel hits that have the characteristics of the much more CPU-intensive Pixelav hits. In particular, it may be the only practical technique available to simulate hits from a radiation damaged detector in CMSSW
An analysis of interplanetary solar radio emissions associated with a coronal mass ejection
Coronal mass ejections (CMEs) are large-scale eruptions of magnetized plasma
that may cause severe geomagnetic storms if Earth-directed. Here we report a
rare instance with comprehensive in situ and remote sensing observa- tions of a
CME combining white-light, radio, and plasma measurements from four different
vantage points. For the first time, we have successfully applied a radio
direction-finding technique to an interplanetary type II burst detected by two
identical widely separated radio receivers. The derived locations of the type
II and type III bursts are in general agreement with the white light CME recon-
struction. We find that the radio emission arises from the flanks of the CME,
and are most likely associated with the CME-driven shock. Our work demon-
strates the complementarity between radio triangulation and 3D reconstruction
techniques for space weather applications
Dispersion of Waves in Relativistic Plasmas with Isotropic Particle Distributions
The dispersion laws of Langmuir and transverse waves are calculated in the
relativistic non-magnetized formalism for several isotropic particle
distributions: thermal, power-law, relativistic Lorentzian and hybrid
. For Langmuir waves the parameters of superluminal undamped, subluminal
damped principal and higher modes are determined for a range of distribution
parameters. The undamped and principal damped modes are found to match
smoothly. Principal damped and second damped modes are found not to match
smoothly. The presence of maximum wavenumber is discovered above that no
longitudinal modes formally exist. The higher damped modes are discovered to be
qualitatively different for thermal and certain non-thermal distributions.
Consistently with the known results, the Landau damping is calculated to be
stronger for non-thermal power-law-like distributions. The dispersion law is
obtained for the single undamped transverse mode. The analytic results for the
simplest distributions are provided.Comment: 8 pages, 12 figures, accepted by Physics of Plasma
Coexistence of orbital and quantum critical magnetoresistance in FeSeS
The recent discovery of a non-magnetic nematic quantum critical point (QCP)
in the iron chalcogenide family FeSeS has raised the prospect of
investigating, in isolation, the role of nematicity on the electronic
properties of correlated metals. Here we report a detailed study of the normal
state transverse magnetoresistance (MR) in FeSeS for a series of
S concentrations spanning the nematic QCP. For all temperatures and
\textit{x}-values studied, the MR can be decomposed into two distinct
components: one that varies quadratically in magnetic field strength
and one that follows precisely the quadrature scaling form
recently reported in metals at or close to a QCP and characterized by a
\textit{H}-linear MR over an extended field range. The two components evolve
systematically with both temperature and S-substitution in a manner that is
determined by their proximity to the nematic QCP. This study thus reveals
unambiguously the coexistence of two independent charge sectors in a quantum
critical system. Moreover, the quantum critical component of the MR is found to
be less sensitive to disorder than the quadratic (orbital) MR, suggesting that
detection of the latter in previous MR studies of metals near a QCP may have
been obscured.Comment: 19 pages (including Supplemental Material), 12 figure
The oblique firehose instability in a bi-kappa magnetized plasma
In this work, we derive a dispersion equation that describes the excitation
of the oblique (or Alfv\'en) firehose instability in a plasma that contains
both electron and ion species modelled by bi-kappa velocity distribution
functions. The equation is obtained with the assumptions of low-frequency waves
and moderate to large values of the parallel (respective to the ambient
magnetic field) plasma beta parameter, but it is valid for any direction of
propagation and for any value of the particle gyroradius (or Larmor radius).
Considering values for the physical parameters typical to those found in the
solar wind, some solutions of the dispersion equation, corresponding to the
unstable mode, are presented. In order to implement the dispersion solver,
several new mathematical properties of the special functions occurring in a
kappa plasma are derived and included. The results presented here suggest that
the superthermal characteristic of the distribution functions leads to
reductions to both the maximum growth rate of the instability and of the
spectral range of its occurrence
Rapid weight loss habits before a competition in sambo athletes
Background: Like other combat sports, sambo has competition rules that divide athletes into categories based on gender, age and weight. Athletes in combat sports often resort to rapid weight loss (RWL) methods to be more competitive in lower weight categories and gain an advantage against lighter, smaller and weaker competitors. The aim of this study was to examine the methodology implemented by two different sambo age categories, junior and senior athletes, in order to attain RWL. Methods: The sample consisted of 103 male sambo elite athletes (seniors/juniors: age 28.5 ± 4.3/18.9 ± 0.8; height (m): 1.7 ± 0.1/1.8 ± 0.1; weight (kg): 76.3 ± 17.8/74.4 ± 16.3; BMI (kg/m2): 25.0 ± 3.8/23.7 ± 3.9) who completed a survey on RWL. Results: Athletes reported losing a mean of 5 kg starting approximately 12 days before a competition. The most common methodology reported by senior and junior sambo athletes was gradually increasing dieting, followed by sauna and plastic suit training. Less common methods adopted were laxatives, diuretics, the use of diet pills and vomiting. There were significant group differences for sauna and diet pill ingestion. Coaches and parents are influential people in the lives of athletes concerning the weight loss strategy to be adopted. Conclusions: This studyâs results unequivocally confirm the prevalent practice of RWL in both senior and junior sambo athletes. Although athletes prevalently chose âless harmfulâ methods, there is a need to inform parents and coaches of the risks and benefits of RWL
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