Investment managers connected to plans sponsors are more likely to be hired than not-connected managers. The magnitude of the selection effect is comparable to that of prior performance. Ex post, connections do not result in higher post-hiring returns. Relationships are thus conducive to asset gathering by investment managers but do not generate commensurate pecuniary benefits for plan sponsors.

We document the causal effects of single-name options trading on the absolute level of information content of prices (stock price informativeness) by exploiting the Penny Pilot Program as an exogenous shock to options trading volume. We find that options trading increases underlying stock price informativeness and information acquisition by both option and stock investors, consistent with the framework of Goldstein and Yang (2015). The findings are driven by firms for which options are more important sources of information and firms with more efficiently priced options. Options market introduction in a sample of 25 other economies also leads to higher price informativeness.

Corporate bond returns exhibit predictability in a manner consistent with efficient pricing. Many equity characteristics, such as accruals, standardized unexpected earnings, and idiosyncratic volatility, do not impact bond returns. Profitability and asset growth are negatively related to corporate bond returns. Because firms that are profitable or have high asset growth (and hence more collateral) should be less risky, with lower required returns, the evidence accords with the risk–reward paradigm. Past equity returns are positively related to bond returns, indicating that equities lead bonds. Cross-sectional bond return predictors generally do not provide materially high Sharpe ratios after accounting for trading costs.

Models that examine investors’ motivations to trade often make opposite predictions about the relation between trading decisions and past returns. We find that, in the aggregate, both buyer- and seller-initiated trades increase with past returns. The difference between buyer- and seller-initiated trades is negatively related to short horizon returns but positively related to returns over longer horizons. Tax-loss-related seller-initiated trades in December and January are accompanied by increased buyer-initiated trades. Past returns significantly affect trading decisions, and these findings are consistent with a number of different models of trading behavior.

In the United States, momentum portfolios formed from 12 to 7 months prior to the current month deliver higher future returns than momentum portfolios formed from 6 to 2 months prior, suggesting an “echo” in returns. In 37 countries excluding the United States, there is no robust evidence of such an echo. In portfolios that combine securities in developed and emerging markets, or across three major geographic regions (Americas excluding United States, Asia, and Europe), there is also no evidence of an echo. Any echo in the United States appears to be driven largely by a carryover of short-term reversals from month − 2.

Epitaxial Ba2YNbO6 (BYNO) films were deposited on textured NiW substrates via pulsed laser deposition. The films have dense and smooth surface structure, and more importantly, significantly improved out-of-plane texture, compared with the NiW substrate texture. Transmission electron microscopy study confirms the c-axis tilting of BYNO film and formation of misfit dislocations at NiW/BYNO interface, suggesting that the improved texture should be attributed to the tilted epitaxy via biased dislocation mechanism. YBa2Cu3O7−δ films deposited on BYNO single-buffered NiW substrates show further texture improvement, high superconducting transition temperature of ~91 K, and critical current density of 1.8 MA/cm2 at 77 K, self-field.

Technological applications of high temperature superconductors (HTS) require high critical current density, Jc, under operation at high magnetic field strengths. This requires effective flux pinning by introducing artificial defects through creative processing. In this work, we evaluated the feasibility of mixed-phase LaMnO3:MgO (LMO:MgO) films as a potential cap buffer layer for the epitaxial growth and enhanced performance of YBa2Cu3O7-δ (YBCO) films. Such composite films were sputter deposited directly on IBAD-MgO templates (with no additional homo-epitaxial MgO layer) and revealed the formation of two phase-separated, but at the same time vertically aligned, self-assembled composite nanostructures that extend throughout the entire thickness of the film. The YBCO coatings deposited on these nanostructured cap layers showed correlated c-axis pinning and improved in-field Jc performance compared to those of YBCO films fabricated on standard LMO buffers. Microstructural characterization revealed additional extended disorder in the YBCO matrix. The present results demonstrate the feasibility of novel and potentially practical approaches in the pursuit of more efficient, economical, and high performance superconducting devices.

High-quality lanthanum zirconium oxide (La2Zr2O7 or LZO) films have been deposited and processed on Ni–W substrates using a sol-gel processing approach. It has been demonstrated that crack-free coatings with thicknesses up to 100 nm can be processed in a single step, while thicker coatings (200–225 nm) were processed using a multiple coating and annealing process. Using simulated metalorganic deposition (MOD)-YBa2Cu3O7−δ (YBCO) processing conditions, the barrier properties of the sol-gel LZO coating with a thickness of 120 nm were found to be comparable to that of the standard 3-layer buffer stack deposited using physical vapor deposition. Secondary ion mass spectroscopy depth profile analysis of LZO films annealed in oxygen-18 shows that LZO effectively stops the diffusion of Ni within the first 80–100 nm. Using MOD processes, a CeO2 cap layer and superconducting YBCO layer were deposited on sol-gel LZO/Ni–W. For the first time, using such an all-solution conductor architecture, a critical current (Ic) of 140 A/cm with a corresponding critical current density (Jc) of 1.75 MA/cm2 has been demonstrated. Using a very thin Y2O3 seed layer (∼10 nm) deposited by electron beam evaporation; improved texture quality in the LZO layers has been demonstrated. The performance of the LZO deposited on these samples was evaluated using a sputtered CeO2 cap layer and MOD YBCO layer. Critical currents of up to 255 A/cm (3.2 MA/cm2) with 0.8-μm-thick YBCO films have been demonstrated, comparable to the performance of films grown using physical vapor deposited yttria stabilized zirconia as a barrier layer. Similar experiments using an MOD-CeO2 cap layer and MOD-YBCO layer yielded critical currents of 200 A/cm (2.5 MA/cm2) with 0.8-μm-thick YBCO films.

Objective: In children cerebrospinal fluid (CSF) otorhinorrhoea can be due to congenital inner-ear malformations. Cochlear dysplasia associated with a defect in the stapes footplate is usually the cause of the CSF leak. Repair of the CSF leak in these cases is usually done by packing the vestibule with muscle or fascia. This traditional method of repair has a 30 to 60 per cent failure rate.

Material and methods: CSF otorhinorrhoea due to congenital inner-ear anomalies in four patients was repaired using multiple-layer packing of the vestibule with glue, muscle and fascia, reinforced by a pedicle temporalis muscle graft. Intra-operatively, continous lumbar drainage wasperformed.

Results: Repair of the CSF leak was successful in four cases and no recurrence was noticed. Inner-ear magnetic resonance imaging (MRI) using three-dimensional fast-spin echo (3D FSE) T2-weighted imaging (T2WI) and 3D steady-state free precession (FIESTA) sequences was found to be a very helpful, noninvasive investigation to localize the site and route of the CSF leak.

Conclusions: Children presenting with recurrent meningitis and CSF rhinorrhoea should be investigated for congenital inner-ear anomalies. In these cases CSF fistulae should be repaired using fibrin or cyanoacrylate glue and intra-operative continuous lumbar drainage; 3D FSE T2WI and 3D FIESTA MRI sequences of the inner ear are helpful.

This article provides an overview of the fabrication of epitaxial, biaxially aligned buffer layers on rolling-assisted biaxially textured substrates (RABiTS) as templates for YBCO films carrying high critical current densities.The RABiTS technique uses standard thermomechanical processing to obtain long lengths of flexible, biaxially oriented substrates with smooth surfaces.The strong biaxial texture of the metal is conferred to the superconductor by the deposition of intermediate metal and/or oxide layers that serve both as a chemical and a structural buffer.Epitaxial YBCO films with critical current densities exceeding 3 106A/cm2at 77K in self-field have been grown on RABiTS using a variety of techniques and demonstrate magnetic-field-dependent critical current values that are similar to those of epitaxial films on single-crystal ceramic substrates.The RABiTS architecture most commonly used consists of a CeO2 (sputtered)/YSZ (sputtered)/Y203 (e-beam)/Ni-W alloy.

The desired texture of the base metal has been achieved in 100 m lengths and 10cm widths.Scaleable and cost-effective techniques are also being pursued to deposit the epitaxial multilayers.The results discussed here demonstrate that this technique is a viable route for the fabrication of long lengths of high-critical-current-density wire capable of carrying high currents in magnetic fields and at temperatures accessible by cooling with relatively inexpensive liquid nitrogen (up through the 77K range).

This paper studies the link between population age structure, net outflows (dividends plus repurchases less net issues) from the stock market, and stock market returns in an overlapping generations framework. I find support for the traditional lifecycle models—the outflows from the stock market are positively correlated with the changes in the fraction of old people (65 and over) and negatively correlated with the changes in the fraction of middle-aged people (45 to 64). Changes in population age structure also add significant explanatory power to equity premium regressions. The population structure adds to the predictive power of regressions involving the investment/savings rate for the U.S. economy. Finally, international demographic changes have some power in explaining international capital flows.

Single-walled carbon nanotubes (SWCNTs) have been grown for the first time by microwave plasma-enhanced chemical vapor deposition (PECVD) at 800°C using methane as the precursor and bimetallic Mo/Co catalyst supported on MgO dispersed on a silicon wafer. The nanotubes grown consist of bundles, each composed of individual tubes of a single diameter associated with either metallic or semiconducting SWCNTs, based on characterization by Raman spectroscopy. Field-emission scanning electron microscopy and atomic force microscopy show that the bundles are relatively thin – 5 to 10 nm in diameter – and up to a few micrometers in length. The results are compared with those obtained on recently reported SWCNTs grown by radio frequency PECVD.