1,880 research outputs found
Neutrino Masses and Mixing in Brane-World Theories
We present a comprehensive study of five-dimensional brane-world models for
neutrino physics based on flat compactifications. Particular emphasis is put on
the inclusion of bulk mass terms. We derive a number of general results for
such brane-world models with bulk mass terms. In particular, in the limit of
small brane-bulk couplings, the electroweak eigenstates are predominantly given
as a superposition of three light states with non-trivial small admixtures of
bulk states. As a consequence, neutrinos can undergo standard oscillations as
well as oscillation into bulk Kaluza-Klein states. We use this structure to
construct a specific model based on Z_2 orbifolding and bulk Majorana masses
which is compatible with all observed oscillation phenomena. The solar neutrino
deficit is explained by oscillations into sterile bulk states while the
atmospheric neutrino deficit is due to mu - tau oscillations with naturally
maximal mixing. In addition, the model can accommodate the LSND result and a
significant neutrino dark matter component. We also analyze the constraints
from supernova energy loss on neutrino brane-world theories and show that our
specific model is consistent with these constraints.Comment: 45 pages, Latex, 1 eps-figur
Compulsory [Mis]Joinder: The Untenable Intersection of Sovereign Immunity and Federal Rule of Civil Procedure 19
Federal Rule of Civil Procedure 19 defines circumstances in which a court can (and must) override the plaintiff¿s party structure to ensure that so-called necessary and required parties are before the court, as complete justice requires. Sovereign immunity protects classes of sovereigns and their political arms from accountability in other nations¿ court systems. Although seemingly unrelated, conflict between these doctrines is increasingly precipitating incongruous outcomes in federal courts¿as evident in a recent Supreme Court decision¿eviscerating the goals of compulsory joinder and unreasonably enlarging the ambit of sovereignty¿s protections to shield nonsovereign parties. The failure of courts to work solutions to the Rule 19/sovereign immunity conundrum risks recreating the systemic failures of the original version of Rule 19¿foregoing the Rule¿s intended pragmatism in favor of doctrinal adherence to labels and categorizations
Session 3-3-C: The National Longitudinal Study of Gambling Behaviour (NLSGB): Preliminary Results
Introduction
The NLSGB tracked 300 gamblers over a 15-month period.
A comprehensive survey instrument was compiled to analyse factors that might influence changes in risk of gambling problems over time.
The study was conducted in the four major metropolitan areas of South Africa: Johannesburg, Tshwane, Durban and Cape Town. We will discuss the study’s design and implementation and some preliminary results
Smoking and Intertemporal Risk Attitudes
Atemporal risk preferences, time preferences, and intertemporal risk preferences are central to economic explanations of addiction, but have received little attention in the experimental economic literature on substance use. We conduct an incentive-compatible experiment designed to elicit the atemporal risk preferences, time preferences, and intertemporal risk preferences of a sample of student (n = 145) and staff (n = 111) smokers, ex-smokers, and non-smokers at the University of Cape Town in 2016-2017. We estimate a structural model of intertemporal risk preferences jointly with a rank-dependent utility model of choice under atemporal risk and a quasi-hyperbolic model of time preferences. We find no substantive differences in atemporal risk preferences according to smoking status, smoking intensity, and smoking severity, but do find that time preferences have an economically significant association with smoking behaviour. Smokers discount at a far higher rate than non-smokers, and ex-smokers discount at a level between these groups. There is also a large, positive relationship between smoking intensity and discounting behaviour that has important implications for treatment. The intertemporal risk preferences of our sample exhibit significant heterogeneity and we find, contrary to the assumption employed by some economic models, that smokers do not exhibit intertemporal risk seeking behaviour. Instead, our sample is characterised by high levels of intertemporal risk aversion which varies by smoking intensity and smoking severity in men, but not in women
Team agency and conditional games
We consider motivations for acknowledging that people participate in multiple levels of economic agency. One of these levels is characterized in terms of subjective utility to the individual; another, frequently observed, level is characterized in terms of utility to social groups with which people (temporarily) identify. Following Bacharach (2006), we describe such groups as ‘teams’. We review Bacharach’s theory of such identification in his account of ‘team reasoning’. While this conceptualization is useful, it applies only to processes supported by deliberation. As this is only one of a range of causal mechanisms underlying behaviour by humans and other strategic agents, a more general account is desirable. We then argue that Stirling’s (2012) account of ‘conditional games’ achieves the desired generalization
Molecular Tagging Velocimetry Development for In-situ Measurement in High-Temperature Test Facility
The High Temperature Test Facility, HTTF, at Oregon State University (OSU) is an integral-effect test facility designed to model the behavior of a Very High Temperature Gas Reactor (VHTR) during a Depressurized Conduction Cooldown (DCC) event. It also has the ability to conduct limited investigations into the progression of a Pressurized Conduction Cooldown (PCC) event in addition to phenomena occurring during normal operations. Both of these phenomena will be studied with in-situ velocity field measurements. Experimental measurements of velocity are critical to provide proper boundary conditions to validate CFD codes, as well as developing correlations for system level codes, such as RELAP5 (http://www4vip.inl.gov/relap5/). Such data will be the first acquired in the HTTF and will introduce a diagnostic with numerous other applications to the field of nuclear thermal hydraulics. A laser-based optical diagnostic under development at The George Washington University (GWU) is presented; the technique is demonstrated with velocity data obtained in ambient temperature air, and adaptation to high-pressure, high-temperature flow is discussed
Modifying and Validating a Quality of Life Measure to Fit Your Patient Population
Introduction: A well-developed quality of life (QoL) instrument is valuable in identifying the burden of illness. We were interested in exploring whether existing QoL instruments were suitable for patients in our medical setting and, if not, whether this could be rectified by adapting an existing valid and reliable instrument to meet the specific needs of our patient population. For the purposes of this study, we chose to evaluate the quality of life of patients with breast cancer. Specifically, we were interested in two aspects of QoL in women with breast cancer. The first was whether existing instruments were pertinent to the women in our venue. The second research interest was dependent upon the first. If current instruments were found wanting, could this be rectified through the creation and validation of new domains of relevance to these patients?
Method: First, five patients were interviewed to ascertain QoL issues pertinent to women in our medical setting. Second, to determine regional appropriateness of existing breast cancer QoL instruments, a search was conducted to identify and review existing breast cancer specific QoL instruments. Third, an addendum was created (to be used in conjunction with an existing instrument identified through the search) that contained three QoL domains not typically found: Financial, Spirituality and Satisfaction with Medical Care. The addendum was then tested along with an existing instrument (FACT-B).
Results: Internal consistency for the new scales, Satisfaction with Medical Care, Spirituality, and Financial had alpha coefficients of 0.81, 0.80, and 0.63 respectively. The total score for FACT-B plus addendum was 0.69. Pearson’s correlation coefficients were 0.49 for Financial, 0.64 for Satisfaction with Medical Care, and 0.70 for Spirituality. Total test/retest was 0.71
Application-Oriented Benchmarking of Quantum Generative Learning Using QUARK
Benchmarking of quantum machine learning (QML) algorithms is challenging due
to the complexity and variability of QML systems, e.g., regarding model
ansatzes, data sets, training techniques, and hyper-parameters selection. The
QUantum computing Application benchmaRK (QUARK) framework simplifies and
standardizes benchmarking studies for quantum computing applications. Here, we
propose several extensions of QUARK to include the ability to evaluate the
training and deployment of quantum generative models. We describe the updated
software architecture and illustrate its flexibility through several example
applications: (1) We trained different quantum generative models using several
circuit ansatzes, data sets, and data transformations. (2) We evaluated our
models on GPU and real quantum hardware. (3) We assessed the generalization
capabilities of our generative models using a broad set of metrics that
capture, e.g., the novelty and validity of the generated data.Comment: 10 pages, 10 figure
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