How does credit market distortion affect corporate investment efficiency? The role of managerial forecast

The purpose of this paper is to study the interaction among corporate investment efficiency, credit supply distortion and managerial forecast ability in China. We provide robust evidence that credit distortion adversely affects corporate investment efficiency, while better managerial forecast ability mitigates this negative effect. Subsample analyses show that managerial forecast ability mitigates the adverse effect of credit supply distortion for non-state-owned enterprises but not for state-owned enterprises. We also find evidence that negative credit supply distortions have a greater impact on corporate investment efficiency and managerial forecast ability is particularly important in reducing underinvestment

Glass-on-2-D-material photonics

Due to their extraordinary optoelectronic properties, 2-D materials have been identified as promising materials for integrated photonics. However, most 2-D material-integrated photonic devices demonstrated to date are fabricated by transferring a layer of 2-D material on top of already fabricated photonic structures, which limits full utilization of their capability. Here we introduce a new photonic integration approach via direct deposition and fabrication of chalcogenide glass photonic devices on 2-D materials.We have applied the new process to fabricate high-performance, broadband on-chip graphene-based optical polarizers with a high contrast ratio of 740 dB/cm leveraging the remarkable optical anisotropy of graphene, and thermo-optic switches with a record heating efficiency of 10 nm/mW using in-waveguide low-loss (20 dB/cm) graphene transparent electrodes. The low processing temperatures of chalcogenide glasses further enables monolithic integration on plastics and the first waveguide-integrated graphene photodetector on flexible substrates. Last but not least, we have also demonstrated monolithic integration of chalcogenide photonic components on several other 2-D materials including WSe2, WS2, and MoTe2. The glass-on-2-D-material approach therefore provides a facile universal route for photonic integration based on 2-D materials

Chalcogenide Glass-on-Graphene Photonics

Two-dimensional (2-D) materials are of tremendous interest to integrated photonics given their singular optical characteristics spanning light emission, modulation, saturable absorption, and nonlinear optics. To harness their optical properties, these atomically thin materials are usually attached onto prefabricated devices via a transfer process. In this paper, we present a new route for 2-D material integration with planar photonics. Central to this approach is the use of chalcogenide glass, a multifunctional material which can be directly deposited and patterned on a wide variety of 2-D materials and can simultaneously function as the light guiding medium, a gate dielectric, and a passivation layer for 2-D materials. Besides claiming improved fabrication yield and throughput compared to the traditional transfer process, our technique also enables unconventional multilayer device geometries optimally designed for enhancing light-matter interactions in the 2-D layers. Capitalizing on this facile integration method, we demonstrate a series of high-performance glass-on-graphene devices including ultra-broadband on-chip polarizers, energy-efficient thermo-optic switches, as well as graphene-based mid-infrared (mid-IR) waveguide-integrated photodetectors and modulators

ABO genotype alters the gut microbiota by regulating GalNAc levels in pigs.

peer reviewedThe composition of the intestinal microbiome varies considerably between individuals and is correlated with health1. Understanding to what extend and how host genetics contributes to this variation is paramount yet has proven difficult as few associations have been replicated, particularly in humans2. We herein study the effect of host genotype on the composition of the intestinal microbiota in a large mosaic pig population. We show that, under conditions of exacerbated genetic diversity and environmental uniformity, microbiota composition and abundance of specific taxa are heritable. We map a quantitative trait locus affecting the abundance of Erysipelotrichaceae species and show that it is caused by a 2.3-Kb deletion in the N-acetyl-galactosaminyl-transferase gene underpinning the ABO blood group in humans. We show that this deletion is a ≥3.5 million years old trans-species polymorphism under balancing selection. We demonstrate that it decreases the concentrations of N-acetyl-galactosamine in the gut thereby reducing the abundance of Erysipelotrichaceae that can import and catabolize N-acetyl-galactosamine. Our results provide very strong evidence for an effect of host genotype on the abundance of specific bacteria in the intestine combined with insights in the molecular mechanisms that underpin this association. They pave the way towards identifying the same effect in human rural populations

GRB efficiency and Possible Physical Processes Shaping the Early Afterglow

The discovery by Swift that a good fraction of Gamma Ray Bursts (GRBs) have a slowly decaying X-ray afterglow phase led to the suggestion that energy injection into the blast wave takes place several hundred seconds after the burst. This implies that right after the burst the kinetic energy of the blast wave was very low and in turn the efficiency of production of $\gamma$-rays during the burst was extremely high, rendering the internal shocks model unlikely. We re-examine the estimates of kinetic energy in GRB afterglows and show that the efficiency of converting the kinetic energy into gamma-rays is moderate and does not challenge the standard internal shock model. We also examine several models, including in particular energy injection, suggested to interpret this slow decay phase. We show that with proper parameters, all these models give rise to a slow decline lasting several hours. However, even those models that fit all X-ray observations, and in particular the energy injection model, cannot account self-consistently for both the X-ray and the optical afterglows of well monitored GRBs such as GRB 050319 and GRB 050401. We speculate about a possible alternative resolution of this puzzle.Comment: Accepted for publication in MNRAS, minor revisio

Hierarchical layered titanate microspherulite: formation by electrochemical spark discharge spallation and application in aqueous pollutant treatment

An ultrafast and template-free method to synthesize three-dimensional (3D) hierarchical layered titanate microspherulite (TMS) particles with high surface area is reported. The synthesis makes use of an electrochemical spark discharge spallation (ESDS) process, during which a fast anodic reaction on the titanium surface creates a layer of titanium dioxide that instantly breaks down by the applied electrical field into the solution in the form of titanium oxide particles. The spalled particles readily react with the heated NaOH electrolyte to form the titanate particles. A typical as-prepared TMS with a diameter of 0.4 similar to 1.5 mu m is synthesized by ESDS of Ti foils in 10 M NaOH solution under an applied current density of 0.5 A cm(-2), leading to a reaction yield of approximately 0.10 similar to 0.15 g per square centimetre of exposed Ti foil within 20 min. After hydrogen ion exchange, the surface area can reach as high as similar to 406 m(2) g(-1). On the Ti surface, a crystalline rutile TiO2 nanosheet structure is formed, which is attributed to the local exothermic heat caused by the spark discharge. A formation mechanism of the TMS is discussed based on field emission scanning electron microscopy (FESEM), a transmission electron microscopy (TEM) study and Raman scattering spectroscopy analysis. The as-prepared TMS shows excellent adsorption performance compared with a titanate micro-particle (TMP), nanowire (TNW) and nanotube (TNT) when methylene blue (MB) and Pb-II ions are used as representative organic and inorganic pollutants. The mechanism of adsorption has also been discussed.National Research Foundation of Singapore Government [MEWR651/06/160

Unusual one-step formation of Fe2O3/MnO2 core-shell hollow nanorods as a high performance anode material for lithium ion batteries

In the present paper, we propose a facile method toward tuning the interior structure of Fe2O3/MnO2 core-shell nanorods. Through thermal annealing, Fe2O3/MnO2 hollow and Fe2O3/(Fe0.42Mn0.58)2O3/MnO2 solid core-shell nanorods are obtained under the condition of 500 and 600 °C, respectively. We demonstrate that the unusual internal structure transform corresponds to the inward movement of Mn element from the nanorods surface. Owing to the unique core-shell hollow nanostructure, Fe2O3/MnO2 nanorods show excellent electrochemical performances as anodes for lithium ion batteries, whose reversible capacity maintains more than 700 mAhg-1 after 2000 cycles.MOE (Min. of Education, S’pore)Accepted versio