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The Resurgence of State-Owned Enterprise in China under XI Jinping
Get PDFMacAllister Hogan explores the revival of state-owned enterprises (SOEs) under Xi Jinping’s administration. The paper discusses the historical role of SOEs, recent reforms to enhance their efficiency, and the implications of increased state control for China’s economic growth and market dynamic
Development Of A Nephelometer For Characterization Of Calcium Oxalate Crystal Concentrations Within Solution
Get PDFThe prevalence of kidney stones has been steadily increasing over the last 30 years, affecting both men and women across all age groups. This rise is largely attributed to lifestyle changes associated with technological advancements, such as more sedentary lifestyles, dietary shifts towards more processed foods, and an increased incidence of metabolic diseases like diabetes. Despite the growing prevalence of kidney stones, the methods for early detection have remained relatively unchanged. Current testing involves collecting urine samples over a 24-hour period and sending them to a lab for microscopic and dipstick analysis. This process provides a comprehensive overview of urine components but takes several days to complete and offers only a snapshot of the patient’s condition. The aim of this effort is to develop an affordable point-of-care (POC) urinalysis device leveraging advancements in sensing. This device, intended for home or outpatient clinic use, combines elements of traditional microscopy and nephelometry to assess the risk of recurrent kidney stones. Given that kidney stones are primarily composed of calcium oxalate (CaOx), this thesis details the design and development of a prototype nephelometer for determining the scattered light intensity of calcium oxalate crystals in urine samples. The proposed nephelometer offers a promising solution for timely and accurate assessment of kidney stone risk, paving the way for better management and prevention strategies
Atomically Precise Metal Nanoclusters: Tailoring Properties through Doping and Ligand Modifications
No full textMetals exhibit different properties when transitioning from the bulk to the nanoscale. These unique characteristics make metallic nanoparticles important for applications in catalysis, sensing, and other advanced technologies. Atomically precise metal nanoclusters (NCs) are a class of materials that bridge the gap between small molecules and bulk metals, offering molecule-like properties with unique electronic, optical, and catalytic features. However, the synthesis and broader application of NCs remain constrained by challenges such as knowledge gaps in understanding synthetic mechanisms, controlling synthetic parameters for reproducible syntheses, and tailoring their properties for specific functions.
This dissertation addresses these challenges by employing two strategies: (i) doping NCs with heterometals to fine-tune their structural and electronic properties, and (ii) modifying their surface ligands to enhance stability, reactivity, and functionality. The work focuses on the design, synthesis, characterization, and application of metal NCs stabilized by ligands such as N-heterocyclic carbene (NHC), phosphine, carborane dithiol, and antimony-based ligands. These NCs exhibit exceptional catalytic performance in model chemical reactions, such as cyclohexane oxidation and nitrophenol reduction. By systematically studying how ligand environments and doping influence reactivity, this work bridges the gap between fundamental science and practical applications. These insights lay the groundwork for designing next-generation materials with precise and tunable properties for sustainable chemical processes
Modeling of Light Filamentation for Nonlinear Imaging and Waveguiding
Get PDFUltrashort pulses are capable of extremely high powers; in addition to enabling various applications in defense, sensing, and imaging, they provide a useful arena in which to study nonlinear optical phenomena that are observable only at high intensities. Due to these effects, which can include ionization and thermal blooming, simulation of ultrashort pulse propagation is a complicated multiphysics problem. We provide an overview of techniques used to simulate the propagation of ultrashort pulses in the nonlinear regime, including the formation of light filaments due to the competition of Kerr self-focusing and defocusing (e.g. via plasma generation). We discuss both carrier-resolved and envelope propagation models, and present a derivation of one of the former. Next, we describe several recent applications in the field of nonlinear microscopy, with particular attention to the role of simulations to provide predictions which inform and explain the theory present in real-world laboratory experiments. In particular, we study the ability of the supercontinuum generation that occurs in the filamentation regime in Yttrium Aluminum Garnet (YAG) ceramics to enable Coherent Anti-Stokes Raman Scattering Spectroscopy as well as ultrafast 3D imaging via nonlinear fluorescence. Lastly, we discuss the modeling of thermal waveguiding and shockwaves as a result of the formation of intense filaments in air
Dividend yield, dividend payers and cross-sectional return prediction
No full textWe provide evidence that dividend yield better predicts returns among dividend payers than alternative pricing factors, contradicting prior research. First, we calculate dividend yield using only the most recent declaration date, substantially increasing return predictability relative to the trailing yield. Second, asset pricing strategies tend to earn low returns within the mature, profitable firms that pay dividends. Cross-sectional tests suggest dividend yield predicts returns because investors value receiving the dividend, rather than it providing information about future earnings. We conclude that dividend yield is a useful valuation metric for mature and easier-to-value firms that tend to pay dividends
One Year Post-\u3cem\u3eBruen\u3c/em\u3e: An Empirical Assessment
Get PDFIn the year after New York State Rifle & Pistol Association v. Bruen, a steady stream of highly publicized opinions struck down a wide range of previously upheld gun restrictions. Courts declared unconstitutional policies ranging from assault weapon bans to domestic abuser prohibitions to various limits on publicly carrying handguns. Those opinions can frequently be paired with others reaching the opposite conclusion. The extent to which Bruen shook up the Second Amendment landscape and has caused widespread confusion in the courts is starting to come into focus.
This Essay measures Bruen’s aftereffects by statistically analyzing a year’s worth of Second Amendment opinions. We coded more than 450 challenges for dozens of variables including both case and judge characteristics, resulting in a comprehensive post-Bruen Second Amendment dataset. The findings of our analysis provide an objective basis for assessing the upheaval wrought by Bruen and highlight both unanswered questions and immense challenges for Second Amendment doctrine in the coming years
