Liquid-gas separation system Patent

Liquid-gas separator adapted for use in zero gravity environment - drawing

Invariance principle for Mott variable range hopping and other walks on point processes

We consider a random walk on a homogeneous Poisson point process with energy marks. The jump rates decay exponentially in the A-power of the jump length and depend on the energy marks via a Boltzmann--like factor. The case A=1 corresponds to the phonon-induced Mott variable range hopping in disordered solids in the regime of strong Anderson localization. We prove that for almost every realization of the marked process, the diffusively rescaled random walk, with arbitrary start point, converges to a Brownian motion whose diffusion matrix is positive definite, and independent of the environment. Finally, we extend the above result to other point processes including diluted lattices.Comment: 47 pages, minor corrections, submitte

High resistance and raised modulus carbon fibers

The manufacturing process, test procedures and application of high strength, high modulus carbon fibers are described in this patent document

The Impact of State Fiscal Policy on States\u27 Resilience Entering the Great Recession

The U.S. economy entered the Great Recession in December 2007 and exited in June 2009. This national statistic obscures a wealth of state-level data shedding light on the policies and conditions that helped some states withstand that recessionary shock for a time. In this study, we used that state-level data in a parametric regression model, known as survival analysis, to estimate the effects that a state’s fiscal policy had on the timing of its entry into the Great Recession. Consistent with earlier, more general, studies focusing on economic growth, we found that taxes have the potential to hasten the start of a state’s recession, while expenditures could defer that event. However, not all types of taxes and expenditures were equivalent in terms of their effect on recessionary timing. Most notably, our results showed that corporate income taxes had a different timing effect than sales, property, and individual income taxes. In addition, although total expenditures tended to delay the Great Recession’s onset, relatively few individual expenditure types had a statistically-significant impact on recessionary timing. Overall, our results suggest that, while taxes likely increase a state’s recessionary risk and expenditures likely decrease it, that narrative is an oversimplification of the complex role played by fiscal policy in determining a state\u27s ability to resist a negative economic shock like the Great Recession

Bank capital regulation with and without state-contingent penalties

A moral hazard model with exogenous bank franchise value is used to analyze bank capital regulation. Banks choose their capital structure as well as the riskiness and mean of their portfolio. The portfolio mean is determined by the level of costly screening. Screening and portfolio risk are private information, so there are two dimensions to the moral hazard problem. Deposit insurance gives banks an incentive to hold less capital, and to choose a higher-risk, lower-mean portfolio. To mitigate these incentives, capital requirements with and without ex post fines are studied. We find an endogenous reverse mean-variance trade-off in banks' portfolios. Prudent banks choose high-screening, low-risk portfolios and are virtually self regulating. Imprudent banks choose low-screening, high-risk portfolios. Without state-contingent penalties, optimal capital regulations are often V-shaped in bank franchise value. Adding state-contingent regulation can significantly lower capital requirements. Optimal state-contingent regulations are characterized by fines on extreme right-hand-tail returns.Bank capital

An LED-based Flasher System for VERITAS

We describe a flasher system designed for use in monitoring the gains of the photomultiplier tubes used in the VERITAS gamma-ray telescopes. This system uses blue light-emitting diodes (LEDs) so it can be operated at much higher rates than a traditional laser-based system. Calibration information can be obtained with better statistical precision with reduced loss of observing time. The LEDs are also much less expensive than a laser. The design features of the new system are presented, along with measurements made with a prototype mounted on one of the VERITAS telescopes.Comment: Accepted for publication in Nuclear Instruments and Methods in Physics Research

So Now What? Using the New Science to Design a Flexible and Adaptable Spiritual Growth Process for New and Returning Believers in the Local Church

This dissertation addresses the need for spiritual-growth opportunities in the local church for new adult Christians and those adults who are returning to the church after years of absence. This dissertation will identify concepts from the new science\u27 of quantum mechanics, chaos theory, and complexity theory to suggest elements for the creation of a flexible and adaptable spiritual-growth process. I use the New Testament to address two assumptions of the thesis: that the spiritual growth of followers of Jesus Christ is a process of spiritual transformation that rests not a one-time conversion event but occurs over a lifetime of dynamic growth, and that the spiritual growth of believers is designed to occur in community with other believers, in the church. I next examine the new science of quantum mechanics, chaos theory, and complexity theory and derive six concepts from them that a local church could use in designing a spiritual-growth process. I then examine the catechumenate of the early centuries of the church (particularly Augustine\u27s De Catechizandis Rudibus), the Spiritual Exercises of Ignatius, John Wesley\u27s class meetings, and the Willow Creek Community Church small-group model to discern ways in which the church has tried to help new believers in the church to grow in their relationship to Jesus Christ. I consider ways in which these models interface with the six concepts from the new science set out in chapter four as well as additional insights that these models offer. In the last chapter, I use an example to suggest the kind of process that I envision. I apply the six concepts proposed from the new science, ideas from the historical models studied, and ideas from the example to propose elements for the creation of a spiritual-growth process

Gills develop early in coral reef fishes: respiratory and ionoregulatory processes

Coral reef ecosystems are among those that are most heavily impacted by anthropogenic disturbances, including climate change, overfishing, and other activities resulting in habitat loss. Consequently, studies have found that fish exposed to these disturbances respond negatively, both behaviourally and physiologically. However, these studies have primarily focused on adult fishes; whereas early life stages – the seeds of adult populations – are substantially understudied. Nonetheless, early life stages are thought to be most vulnerable to environmental stress, owing to rudimentary organs and underdeveloped physiological systems. Processes that are likely to be impacted are those related to the respiratory (oxygen and carbon dioxide exchange) and ion/osmoregulatory (ion and water balance) systems because of potential mismatch between the environmental pressures and the pace at which these systems develop. In fish, respiration and ion/osmoregulation are known to primarily occur at the gills; however, during early life stages, before the gills form, these physiological processes are maintained through cutaneous pathways. The transition of these processes from cutaneous (i.e., skin) to branchial (i.e., gill) has been thoroughly investigated in model species, such as the rainbow trout (Oncorhynchus mykiss), where it is thought that gills begin functioning for ion regulation (15 days post hatch; dph) before oxygen uptake (23-28dph). This information is not known for coral reef fishes. Although, this transition is thought to occur earlier in coral reef fishes than in temperate species, like the rainbow trout, because of the influence of warm temperatures and low oxygen levels on metabolic processes. In addition, this transition is thought to be energetically costly under ideal environmental conditions, and perhaps, further exacerbated by anthropogenic stressors. Developmental deficiencies to those systems could lead to reductions in whole organism performance and ecosystem health. The following thesis investigates gill development in coral reef fish species with the aim to determine the onset of respiratory and ionoregulatory systems. This is the knowledge base needed to better predict how anthropogenic stress could affect coral reef ecosystems. To do this, two coral reef fish species (Acanthochromis polyacanthus and Amphiprion melanopus) were chosen. As pomacentrids, these two species belong to one of the most speciose coral reef fish families and are of high ecological importance. In addition, both are easily maintained in captivity, life cycles have been closed, genomes fully sequenced, and as a result, both are quickly becoming model laboratory species. This further highlights the importance of understanding the development of these basic but critical processes associated with respiration and ion regulation. The first experiments (Chapter 2) were designed to describe, in detail, the ontogeny of gill development in two coral reef fishes. I found gill tissues to form, in these two species, faster than in any other studied fish to date. Specifically, all gill structures were apparent prior to hatching. The onset of gill development may be a critical developmental window, as it is often associated with high mortality, and therefore, should be a milestone that future studies consider when investigating coral reef fish populations. The accelerated developmental pace observed in these two coral reef fish species is perhaps related to the environmental conditions they experience (e.g., warm water temperatures during the day and low oxygen levels at night) that demand respiratory efficiency. Theoretically, the onset of gill development should coincide with increased oxygen requirements beyond what can be provided through cutaneous pathways (i.e., the oxygen hypothesis). In chapter 3, I tested this hypothesis by measuring the oxygen uptake of Amphiprion melanopus and Acanthochromis polyacanthus over their embryonic development. When fish start using their blood (i.e., using haemoglobin; Hb, the oxygen carrying protein found in nearly all vertebrate species) to bind oxygen from the environment and deliver it to their tissues, they are presumably using the gills to do this. If I inhibit the function of Hb (e.g., using phenylhydrazine (PHZ) to breakdown Hb), the fish is then only able to rely on cutaneous pathways to uptake oxygen. Therefore, when Hb is required to enhance oxygen transport, this should coincide with the onset of gill function for respiration. I found that, prior to hatching, embryos are able to satisfy oxygen demand via cutaneous pathways (i.e., in the absence of hemoglobin) alone. Upon hatching, cutaneous respiration was insufficient, suggesting that gills are critical for respiration after this stage. Linking these physiological findings with observations of gill development in coral reef fish obtained in chapter 2, my results suggest that the rapid onset of gill formation during embryogenesis is essential to meet oxygen requirements of fish larvae immediately after hatching. However, the presence of gill tissue before it is required for branchial oxygen uptake suggests that other processes may be initiating and requiring gill formation pre-hatch. The ionoregulatory hypothesis suggest that cutaneous processes for ion/osmoregulatory balance become insufficient before those for respiration because transporters are localised within specialised cells. Therefore, surface area to volume ratios (SA/V) will limit ion exchange before limiting respiration. In chapter 4, I used immunohistochemistry to observe the primary enzymatic ion exchanger, Na+ K+ ATPase (NKA), on the skin, yolk-sac, and the gills in developing embryos of two coral reef fish species to determine when ion regulation processes begin. I found NKA to first appear on the skin and yolk-sac at 1-2 days post fertilization (dpf) and on the gill filaments at 3-5 dpf. My study is the first to provide evidence that coral reef fishes use NKA external to the gills, i.e., through cutaneous pathways. Additionally, these fishes show an accelerated developmental pace of ion regulation, with the earliest appearance of NKA on the skin and the gills in any species investigated to date. The early appearance of ionoregulatory cells on the gills before the formation of lamellae and before the onset of branchial oxygen uptake suggests that ion regulation is the primary driver underpinning gill development in these fishes. My findings support the ionoregulatory hypothesis. The first critical developmental window for coral reef fishes is prior to hatching, when gills begin to form. Therefore, anthropogenic stressors or other environmental perturbations that could disrupt gill development pre-hatch may preclude healthy adult populations and coral reef ecosystems. Here, I emphasize that embryonic life stages must be considered when investigating the impacts of anthropogenic stressors on coral reef fishes. Processes performed by the gills, if impeded, could have negative cascading effects throughout development and into adulthood. Overall, understanding the structure and function of gills and how and when they develop is essential to understanding fish ecology and evolution, but can also be key to effectively managing fish populations in a changing world

Jumping the Shark: The Case for Repealing the TEFRA Partnership Audit Rules

By their very nature, partnerships present problems for the U.S. tax system. Are they separate entities or just aggregates of their partners? It depends on the situation. Prior to 1982, the Internal Revenue Service had little choice but to audit the tax consequences of partnership activities by auditing each partner. Congress flipped that aggregate treatment on its head by enacting entity-focused partnership audit rules in the Tax Equity and Fiscal Responsibility Act of 1982. It’s time to flip them back. Neither the practical problems that drove creation of the entity-focused partnership audit rules nor the tax policyrationales used to justify them retain strength today. Indeed, almost thirty years of experience with those rules has unearthed numerous negative consequences. Furthermore, improvements in the substantive law applicable to partnerships and in the technology available to the Internal Revenue Service for use in auditing partnerships have significantly reduced the benefits derived from the current partnership audit rules. In short, their costs now outweigh their benefits and they should be repealed

Adaptive cancelation of self-generated sensory signals in a whisking robot

Sensory signals are often caused by one's own active movements. This raises a problem of discriminating between self-generated sensory signals and signals generated by the external world. Such discrimination is of general importance for robotic systems, where operational robustness is dependent on the correct interpretation of sensory signals. Here, we investigate this problem in the context of a whiskered robot. The whisker sensory signal comprises two components: one due to contact with an object (externally generated) and another due to active movement of the whisker (self-generated). We propose a solution to this discrimination problem based on adaptive noise cancelation, where the robot learns to predict the sensory consequences of its own movements using an adaptive filter. The filter inputs (copy of motor commands) are transformed by Laguerre functions instead of the often-used tapped-delay line, which reduces model order and, therefore, computational complexity. Results from a contact-detection task demonstrate that false positives are significantly reduced using the proposed scheme