Electron heating at interplanetary shocks

Data for 41 forward interplanetary shocks show that the ratio of downstream to upstream electron temperatures. T sub e (d/u) is variable in the range between 1.0 (isothermal) and 3.0. On average, (T sub e (d/u) = 1.5 with a standard deviation, sigma e = 0.5. This ratio is less than the average ratio of proton temperatures across the same shocks, (T sub p (d/u)) = 3.3 with sigma p = 2.5 as well as the average ratio of electron temperatures across the Earth's bow shock. Individual samples of T sub e (d/u) and T sub p (d/u) appear to be weakly correlated with the number density ratio. However the amounts of electron and proton heating are well correlated with each other as well as with the bulk velocity difference across each shock. The stronger shocks appear to heat the protons more efficiently than they heat the electrons

Measurement of polarization-transfer to bound protons in carbon and its virtuality dependence

We measured the ratio $P_{x}/P_{z}$ of the transverse to longitudinal components of polarization transferred from electrons to bound protons in $^{12}\mathrm{C}$ by the $^{12}\mathrm{C}(\vec{e},e'\vec{p})$ process at the Mainz Microtron (MAMI). We observed consistent deviations from unity of this ratio normalized to the free-proton ratio, $(P_{x}/P_{z})_{^{12}\mathrm{C}}/(P_{x}/P_{z})_{^{1}\mathrm{H}}$, for both $s$- and $p$-shell knocked out protons, even though they are embedded in averaged local densities that differ by about a factor of two. The dependence of the double ratio on proton virtuality is similar to the one for knocked out protons from $^{2}\mathrm{H}$ and $^{4}\mathrm{He}$, suggesting a universal behavior. It further implies no dependence on average local nuclear density

The Long-Term P/E Radio

The price-earnings effect has been thoroughly documented and widely studied around the world. However, it has always been calculated on the basis of the previous year’s earnings. We show that the power of the effect has until now been seriously underestimated, due to taking too short-term a view of earnings. We look at all UK companies since 1975, and using the traditional P/E ratio we find the difference in average annual returns between the value and glamour deciles to be 6%, similar to other authors’ findings. We almost double that gap by calculating P/E ratios using earnings averaged over the last eight years. Averaging, however, implies equal weights for each past year. We widen the gap further by optimising the weights of the past years of earnings in the P/E ratio.

Measurement of the branching ratios of the decays Xi0 --> Sigma+ e- nubar and anti-Xi0 --> anti-Sigma+ e+ nu

From 56 days of data taking in 2002, the NA48/1 experiment observed 6316 Xi0 --> Sigma+ e- nubar candidates (with the subsequent Sigma+ --> p pi0 decay) and 555 anti-Xi0 --> anti-Sigma+ e+ nu candidates with background contamination of 215+-44 and 136+-8 events, respectively. From these samples, the branching ratios BR(Xi0 --> Sigma+ e- nubar)= (2.51+-0.03stat+-0.09syst)E(-4) and BR(anti-Xi0 --> anti-Sigma+ e+ nu)= (2.55+-0.14stat+-0.10syst)E(-4) were measured allowing the determination of the CKM matrix element |Vus| = 0.209+0.023-0.028. Using the Particle Data Group average for |Vus| obtained in semileptonic kaon decays, we measured the ratio g1/f1 = 1.20+-0.05 of the axial-vector to vector form factors.Comment: 16 pages, 11 figures Submitted to Phys.Lett.

Effects Of Thoracic Endovascular Aortic Repair On Cardiac Function At Rest

a. Hypothesis: We hypothesize that Thoracic Endovascular Aortic Repair (TEVAR) leads to a decline in cardiac function among post-operative patients. Our primary objective is to identify the changes of cardiac function to post-TEVAR patients at rest using echocardiography studies. With this knowledge, we aim to gain valuable insight into the post-op management of patients with the goal of strategizing post-op care to reduce complications and exacerbation to heart failure. b. Methods: Chart review of the electronic medical record (EMR) was used to collect patient data, patient history, procedural information, outcomes, and echocardiogram parameters. To assess the impact of TEVAR, the echo parameters were then analyzed using a paired sample t-test, comparing pre-TEVAR and post-TEVAR echocardiograms. The alpha level for determining statistical significance was set at p=0.05 for two-sided comparisons. c. Results: Between the pre-TEVAR echo and first post-op echo, average indexed left atrial volume for all patients (n=30) was 35.68 pre-TEVAR and increased to 35.75 post-TEVAR with a p-value of 0.97. Mitral E/A ratio decreased from 1.09 pre-operatively to 1.04 post-operatively. E/A ratio (n=29) with a p-value of 0.92. Average E/e’ ratio increased from 10.59 pre-TEVAR to 10.69 post-TEVAR (n=32) with a p-value of 0.91. Tricuspid regurgitation pressure gradient (TRPG) increased from 24.02 pre-operatively to 26.96 post-operatively (n=22) with a p-value of 0.33. Between the pre-TEVAR echo and second post-op echo, the indexed left atrial volume increased on average by 3.62 after TEVAR (p=0.66). E/A ratio decreased by 0.03 across all patients on average (p=0.66), while E/e’ ratio decreased by 0.25 post-operatively (p=0.31). TRPG increased by 0.92 after TEVAR (p=0.84). d. Conclusions: The data showed a slight upwards trend in TRPG after the first post-op echo. However, no statistically significant changes to diastolic function were seen in patients after TEVAR

Dynamical mean-filed approximation to small-world networks of spiking neurons: From local to global, and/or from regular to random couplings

By extending a dynamical mean-field approximation (DMA) previously proposed by the author [H. Hasegawa, Phys. Rev. E {\bf 67}, 41903 (2003)], we have developed a semianalytical theory which takes into account a wide range of couplings in a small-world network. Our network consists of noisy $N$-unit FitzHugh-Nagumo (FN) neurons with couplings whose average coordination number $Z$ may change from local ($Z \ll N$) to global couplings ($Z=N-1$) and/or whose concentration of random couplings $p$ is allowed to vary from regular ($p=0$) to completely random (p=1). We have taken into account three kinds of spatial correlations: the on-site correlation, the correlation for a coupled pair and that for a pair without direct couplings. The original $2 N$-dimensional {\it stochastic} differential equations are transformed to 13-dimensional {\it deterministic} differential equations expressed in terms of means, variances and covariances of state variables. The synchronization ratio and the firing-time precision for an applied single spike have been discussed as functions of $Z$ and $p$. Our calculations have shown that with increasing $p$, the synchronization is {\it worse} because of increased heterogeneous couplings, although the average network distance becomes shorter. Results calculated by out theory are in good agreement with those by direct simulations.Comment: 19 pages, 2 figures: accepted in Phys. Rev. E with minor change

The Extremes of the P/E Effect

The price-earnings effect has been a challenge to the idea of efficient markets for many years. The P/E used has always been the ratio of the current price to the previous year’s earnings. However, the P/E is partly determined by outside influences, such as the year in which it was measured, the size of the company, and the sector in which the company operates. Looking at all UK companies since 1975, we determine the power of these influences, and find that the sector influences the P/E in the opposite direction to the others. We use a regression to weight the influences according to their power in predicting returns, reversing the sector influence so that it works for us and not against us. The resulting weighted P/E widens the gap in annual returns between the value and glamour deciles by 8%, and identifies a value decile with average returns of 32%.

Decomposing the P/E Ratio

The price-earnings effect has been a challenge to the idea of efficient markets for many years. The P/E used has always been the ratio of the current price to the previous year’s earnings. However, the P/E is partly determined by outside influences, such as the year in which it was measured, the size of the company, and the sector in which the company operates. Looking at all UK companies since 1975, we determine the power of these influences, and find that the sector influences the P/E in the opposite direction to the others. We use a regression to weight the influences according to their power in predicting returns, reversing the sector influence so that it works for us and not against us. The resulting weighted P/E widens the gap in annual returns between the value and glamour deciles by 8%, and identifies a value decile with average returns of 32%.