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The Heavy Odds for a Weaponized and Lawless Outer Space
No full textJust as space commerce appears to have reached a critical mass, competing national government interests can thwart progress with strategies and tactics that increase market risk, volatility, and uncertainty. Despite universal support for a treaty-level commitment to pursue only peaceful activities, for the benefit of everyone, unilateral actions by the governments of China, Russia, and the United States have the potential to disrupt markets and render space a new theater of warfare. These nations appear disinclined to embrace the unenforceable goals contained in five international treaties governing activities in outer space.
So-called Great Power Competition has generated high stakes rivalry to retain or secure supremacy in military, political, economic, and societal spheres. The battle for competitive advantage has the potential to reduce or even thwart continuing success in space markets, because conflict on earth includes an increasingly volatile above ground component.
This article assesses two conflicting trends. On one hand, space commerce in 2023 generated an estimated 1.8 trillion by 2035. Low Earth orbiting satellite constellations have the potential to bridge the Digital Divide by providing a reliable infrastructure for affordable broadband access, even in remote, rural, and impoverished locales throughout the world. Other new market opportunities include development of a vibrant space launch and tourism industry, space exploration, colonization of the Moon and Mars, and an expanded array of services via commercial satellites.
On the other hand, longstanding and emerging challenges in outer space may shift from chronic and unresolved, to acute and potentially catastrophic. National governments and private ventures can avoid triggering worst case scenarios only if they accept compulsory limits on space weapons testing and use, coupled with effective measures to reduce the risk of collisions with discarded or operational spacecraft.
The article identifies the most pressing and emerging quandaries, many of which result from a nation’s failure to comply with limitations on space activity broadly framed by international treaties entered into force over 40 years ago. Because governments of the world have not reached consensus on whether and how to modernize the treaties, the currently in force agreements do not address market entry by private ventures, lack an enforcement mechanism to compel compliance, and rely primarily on the good will of all countries to support noble aspirations that increasingly deviate from individual national interests.
The article also explains how emerging technologies and business plans contribute to both revenue enhancement and greater risk of calamity. It offers specific recommendations on what unconditional and immediate commitments national governments and private ventures must make to avoid potential ruination of space
Prepare for Landing: The DOT’s Authority to Regulate Unfair and Deceptive Practices Amidst the Supreme Court’s Elimination of Chevron Deference
No full textOn June 28, 2024, the Supreme Court overturned Chevron U.S.A., Inc. v. Natural Resources Defense Council, Inc. with their decision in Loper Bright v. Raimondo—holding that judges are not obligated to defer to agency interpretations of the statutes they administer. One month after this decision, the Fifth Circuit Court of Appeals held that the Department of Transportation does not have authority to issue a rule regulating how airlines communicate certain fees to customers during the booking process. This decision contradicts the Seventh Circuit Court of Appeals’ earlier decision to uphold similar DOT regulations attempting to prohibit unfair and deceptive practices in the air travel industry. Therefore, a circuit split arose over the scope of the DOT’s rulemaking authority. This comment addresses the historic scope of the DOT’s predecessor to regulate the aviation industry and the ongoing circuit split regarding the DOT’s current regulatory authority. Specifically, this comment seeks to analyze the impact that the Loper Bright decision will have on the DOT’s future authority to regulate unfair or deceptive practices in the aviation industry. Ultimately, this comment concludes that the Fifth Circuit’s decision accurately predicts the fate of the DOT’s regulatory power, and therefore, it is likely the aviation industry will experience a deregulation effect specifically pertaining to consumer protections
Axial Stiffness Estimation Of Rail Bridges Using Influence Lines
No full textFrom an engineering perspective, risk is defined as any event exposing an individual,machine, or structure to danger. In their function as critical components of transportation networks, rail bridges face various risks throughout their service life which can result in catastrophic failures. As such, robust assessments of these structures through efficient strategies are critical to guarantee public safety. This thesis presents a framework for estimating the axial stiffness of impaired rail truss bridge members, using displacement influence lines (DILs). The proposed framework leverages a mechanical relationship between changes in DILs and nominal contributions of truss members to formulate systems of equations that are representative of damage. These systems are solved using a least-norm scheme to determine its location(s) and extent(s). In this scheme, damage sets define a search space, an optimality criterion determines candidate solutions, and final solutions are obtained by applying constraints on the preliminary solutions. Analytical investigations of various damage scenarios are provided to evaluate the robustness of the proposed framework when noisy DILs are utilized as input
Suitability and Strength of Earthen Cementitious Mixtures
No full textEarth construction is a historically significant building method that has declined in use due to the rapid advancement of modern materials and its less-favorable aesthetics. However, these modern methods have had negative environmental impacts and reduced accessibility to infrastructure development. The construction and demolition industry is also one of the world’s largest generators of solid waste, much of which consists of aggregate - material that earthen construction could effectively reuse. These issues have renewed interest in earthen construction as an environmentally and economically sustainable alternative rooted in long-standing practice. Despite its potential, adoption is hindered by limited understanding, lack of standardization, and minimal research, particularly regarding earthen cementitious mixtures (CMs).
This research addresses these gaps by focusing on earthen CMs with slumps between 8” and 12” - specifically mud grout and Controlled Low Strength Material (CLSM). Building on an in-lab mix design from a Compressed Stabilized Earthen Cylinder experiment by Hillyard and Story (2025), the study develops adapted mixes using additional water to achieve workable earthen CMs. The experiment also explores alternative specimen geometries and mold materials as they relate to compression testing, highlighting inconsistencies across existing standards. Given that earthen CMs prioritize homogeneity and have been largely confined to block applications, this work seeks to expand their potential for broader infrastructure uses such as foundation reinforcement and void filling, while contributing toward more uniform testing standards
Delights of the Cup: Materiality, Function, and Reception of Late Antique Iranian Silver Vessels
No full textThis dissertation aims to reassert the role of materiality in the interpretation of silver vessels produced in the Iranian world during the Sasanian and early Islamic periods (c. 300–900 CE). It argues that the material qualities of silver vessels, along with the sophisticated processes employed in their making, profoundly contributed to the fascination inspired by these objects throughout history. This research also attends to the questions of function and reception. Particularly, it explores how silver vessels were used and physically engaged with in their original setting. This emphasis on the objects’ practical and tangible dimensions leads to a deeper appreciation of their multi-sensory affordances. Furthermore, this dissertation foregrounds a transcultural and transhistorical approach to the study of Iranian silver vessels. As the objects crossed the temporal and geographical boundaries of late antique Iran, their original iconographic significance was often lost, while they adopted new meanings and, in many cases, new functions. Yet, this process of recontextualization did not impact the allure that stemmed from the objects’ material and technical brilliance. This study argues that the transcultural fascination with the materiality of silver vessels is key to unravelling their long-term currency across the wider Eurasian expanse. This dissertation presents the first comprehensive reevaluation of late antique Iranian silver vessels in over four decades and the first art historical analysis of their material, technical, and sensory dimensions
Atomically Precise Metal Nanoclusters For Light-Driven Applications: Fluorescence Chemosensing, Triplet Sensitization, and Aggregation-Induced Emission
No full textAtomically precise metal nanoclusters (MNCs) represent a new regime of highly versatile synthetic materials, with far-reaching applications. Distinct from polydisperse nanoparticles, nanoclusters are molecularly pure compounds which lie on the 1-3 nm scale. This small size enables nanoclusters to exhibit definable HOMO/LUMO band gaps and discrete optical transitions, similar to semiconductor quantum dots. Their fluorescence and phosphorescence characteristics allow them to be used as molecular recognition agents for environmental and bodily contaminants/toxins; this “chemosensing” ability is industrially desirable for the sensitive detection of pesticides, heavy metals, etc., in drinking water, soil, blood, urine, and other settings. Additionally, bimetallic and trimetallic alloyed nanoclusters have been shown to exhibit increased photoluminescence properties. Specifically, NIR-emissive nanoclusters are coveted for medicinal applications such as bioimaging and therapeutics. Further, photoactive clusters can be used as homogeneous catalysts for organic syntheses. However, studies of alloyed nanoclusters remain underexplored, necessitating both more syntheses of multimetal nanoclusters as well as careful cross examination of the effects of heteroatoms by identity, number, and placement in the crystal structure. Herein is a background review of the use of nanoclusters as fluorescent chemosensors, followed by the synthesis and characterization of three novel bimetallic clusters. Each clusters’ optical and luminescence properties are evaluated, including applications in triplet sensitization for singlet oxygen catalysis
Glass Half Full: Strategic Packaging Decisions and Environmental Outcomes
No full textProblem definition: Amid rising environmental concerns and regulatory pressures, firms, particularly beverage manufacturers, face complex trade-offs when choosing among packaging options such as non-recycled plastic, recycled plastic, and glass. While glass is often perceived as the most sustainable option, its true environmental impact depends critically on return and reuse rates, which are influenced by firm-led deposit-refund systems and sustainability advertising. Methodology/results: We develop an analytical model to study a firm\u27s joint decisions on packaging type, pricing, and advertising efforts in a setting with heterogeneous consumer environmental awareness and greenwashing risk. We quantify the conditions under which glass can outperform plastic in terms of profit and emissions---or, paradoxically, lead to higher environmental harm. Under optimal pricing and advertising efforts, the firm can achieve a rare win-win-win : prevent potential greenwashing while simultaneously improving profits and customer utility. We extend the model to examine the effects of recycled content mandates and endogenous deposit values, showing how firms can balance deposit incentives and advertising strategies to engage both environmentally aware and unaware consumers. A calibrated numerical study using data from a regional U.S. dairy firm reveals that adopting the model’s recommended policy—glass packaging with a premium price and targeted advertising—can increase profits by almost 60% while reducing emissions by over 30%. Managerial implications: Our findings can help identify when glass containers outperform plastic alternatives and guide how sustainability advertising and refundable deposits can be leveraged to boost glass return rates, improve environmental outcomes, enhance customer utility, and increase profits
Testing Coleman’s Socioeconomic Status Model And Its Role In Language Development
No full textSocioeconomic Status (SES) is widely used to predict child outcomes, yet its measurement varies widely across studies. This study examines Coleman’s (1998) theoretical model of SES, comprising of Human, Financial and Social Capital, using Confirmatory Factory Analysis (CFA) and Exploratory Structural Equation Modeling (ESEM). Additionally, it evaluates the model’s ability to predict vocabulary scores and aims to access its incremental validity over the widely used Hollingshead Socioeconomic Index (HSEI). Data was collected from 306 caregivers of children aged 15-30 months (m = 23.37; 71.6% Caucasian) via Prolific. CFA results indicated that Coleman’s model was not a good fit for the data. However, ESEM analysis demonstrated a strong fit with two correlated error terms, revealing a three-factor structure that was different from Coleman’s original model. The new model identified three factors: human capital (caregivers’ education level and years of education), wealth/prestige capital (caregivers’ income, income-to-needs ratio, net worth, status and prestige), and neighborhood capital (neighborhood education, income, and poverty). However, neither the new SES model nor HSEI significantly predicted vocabulary scores in this sample. These findings highlight the complexity of SES measurement and underscore the need for a robust theoretical framework in assessing its impact on child development
\u3cem\u3eSalerno\u3c/em\u3e and the Second Amendment
No full textThe Supreme Court’s Second Amendment is beginning to take more concrete shape. In United States v. Rahimi, the Court rejected a challenge to the federal prohibition on gun possession by those subject to certain kinds of restraining orders. In that case, the Court’s analysis hinged in part on the difficulty of successfully waging facial constitutional challenges. It confirmed that the teaching of United States v. Salerno—that a statute is only facially unconstitutional if it has no valid applications—applies fully to the Second Amendment. Although it relied on this procedural lesson from Salerno, the justices overlooked Salerno’s substantive teaching: that contemporary and compelling interests in protecting public safety are not out of bounds in constitutional litigation, but instead are central to how courts should evaluate constitutional claims. This Article fleshes out these twin lessons from Salerno and urges the Court’s consistency in how it thinks about adjudicating individual rights