Hong ZHOU （周宏）

We examine the economic determinants and informational effects of credit rating affirmations (i.e., the reiteration of past credit ratings) for a sample of US public firms from 1995 to 2020. We find that credit rating affirmations typically follow major corporate events and changes in firm fundamentals that increase information uncertainty about a firm's creditworthiness, suggesting that affirmations reduce uncertainty. We further document that rating affirmations provide value‐relevant information to equity and debt investors. Using a short‐window event study method, we show that equity investors react positively to rating affirmations and that information uncertainty around affirmations diminishes. These findings are more pronounced for firms with non‐investment‐grade ratings. We further show that our results strengthen for firms with greater pre‐affirmation information uncertainty. Finally, consistent with our information …

A microphone, comprising at least two electrodes, spaced apart, configured to have a magnetic field within a space between the at least two electrodes; a conductive fiber, suspended between the at least two electrodes; in an air or fluid space subject to waves; wherein the conductive fiber has a radius and length such that a movement of at least a central portion of the conductive fiber approximates an oscillating movement of air or fluid surrounding the conductive fiber along an axis normal to the conductive fiber. An electrical signal is produced between two of the at least two electrodes, due to a movement of the conductive fiber within a magnetic field, due to viscous drag of the moving air or fluid surrounding the conductive fiber. The microphone may have a noise floor of less than 69 dBA using an amplifier having an input noise of 10 nV/√ Hz.

We find that Ohio’s “Vax-a-Million” lottery increased first-dose COVID-19 vaccinations by between 50,000 and 100,000, with most of the additional doses occurring during the two weeks between the announcement and the first lottery drawing. We use county-level data and two empirical approaches to provide causal estimates of the lottery in Ohio. First, a difference-in-differences design compares vaccination rates in border counties in Ohio and Indiana before and after the announcement. Second, we use a pooled synthetic control method to construct a counterfactual for each of Ohio’s counties using control counties in Indiana, Michigan, and Pennsylvania. The synthetic control analysis reveals larger increases in vaccination rates in more populous counties. Our estimates imply that Ohio paid about $75 per additional starting dose during this period.

BackgroundThe proliferation of airway smooth muscle cells (ASMCs) is a key feature of airway remodeling in asthma. Azithromycin (AZM) has been shown to decrease bronchial hyperresponsiveness and airway inflammation in asthmatics; however, the role of AZM in ASMC proliferation remains unclear. Thus, we investigated the effect of AZM on ASMC proliferation in a rat model of experimental asthma.MethodsWe isolated ASMCs from rats sensitized and challenged by ovabulmin (OVA), and then treated with different concentrations of AZM. Cytotoxicity of ASMC was evaluated by Cell Counting Kit-8 (CCK-8) assay, morphological change was examined with laser confocal microscope after Annexin V/propidium iodide (PI) double staining, mitochondrial membrane potential was determined with JC-1 staining, and the expression of cytochrome C was examined by western blot.ResultsThe relative surface areas of …

Comprehensive and spatially mapped molecular atlases of organs at a cellular level are a critical resource to gain insights into pathogenic mechanisms and personalized therapies for diseases. The Kidney Precision Medicine Project (KPMP) is an endeavor to generate three-dimensional (3-D) molecular atlases of healthy and diseased kidney biopsies by using multiple state-of-the-art omics and imaging technologies across several institutions. Obtaining rigorous and reproducible results from disparate methods and at different sites to interrogate biomolecules at a single-cell level or in 3-D space is a significant challenge that can be a futile exercise if not well controlled. We describe a “follow the tissue” pipeline for generating a reliable and authentic single-cell/region 3-D molecular atlas of human adult kidney. Our approach emphasizes quality assurance, quality control, validation, and harmonization across …

BackgroundGinseng has therapeutic potential for treating obesity and the associated gut microbiota dysbiosis. However, whether white ginseng and red ginseng, the two kinds of commonly used processed ginseng, possess different anti-obesity effects remains unknown.PurposeAnti-obesity effects of water extracts of white ginseng and red ginseng (WEWG and WERG) were compared, and the potential mechanisms were discussed.MethodsChemical profiles of WEWG and WERG were characterized by ultra-high performance liquid chromatography-tandem triple quadrupole mass spectrometry (UHPLC-QqQ-MS/MS) and high performance liquid chromatography coupled with evaporative light scattering detector (HPLC-ELSD). Anti-obesity effects of WEWG/WERG were examined by determining fat accumulation, systemic inflammation, enteric metabolic disorders and gut microbiota dysbiosis in high-fat diet (HFD …

Most reported results about phase transition probed by the photoluminescence (PL) spectra of Eu3+ ions are qualitative, but the quantitative analyses of phase transition were presented in this work. We fabricated (Na0.8, K0.2)0.5Bi0.497Eu0.003TiO3 (NKBT20:Eu) ferroelectric ceramics and investigated the phase structures and the PL spectra of NKBT20:Eu ceramics before and after poling at different electric fields. The PL spectra indicate a phase transition from tetragonal phase (T phase) to rhombohedral phase (R phase) within NKBT20:Eu ceramics after poling, consistent with the analyses by X‐ray diffraction (XRD). Moreover, the emission intensity ratios of the “hypersensitive” transition to the magnetic dipole transition could be used to calculate the fractions of the phase transition quantitatively, which were further confirmed by XRD Rietveld refinements. This study provides a different perspective to investigate …

Let k be a field, G be a finite group, k (x (g): g∈ G) be the rational function field with the variables x (g) where g∈ G. The group G acts on k (x (g): g∈ G) by k-automorphisms where h⋅ x (g)= x (h g) for all h, g∈ G. Let k (G) be the fixed field defined by k (G):= k (x (g): g∈ G) G={f∈ k (x (g): g∈ G): h⋅ f= f for all h∈ G}. Noether's problem asks whether the fixed field k (G) is rational (= purely transcendental) over k. Let m and n be positive integers and assume that there is an integer t such that t∈(Z/m Z)× is of order n. Define a group G m, n:=< σ, τ: σ m= τ n= 1, τ− 1 σ τ= σ t>≃ C m⋊ C n. Assume furthermore that (i) m is an odd integer, and (ii) for any e| n, the ideal< ζ e− t, m> in Z [ζ e] is a principal ideal (where ζ e is a primitive e-th root of unity). Theorem. If k is a field with ζ m, ζ n∈ k, then k (G m, n) is rational over k. Consequently, it may be shown that, for any positive integer n, the set S:={p: p is a prime number such that C …