Proton Decay and the Planck Scale

Even without grand unification, proton decay can be a powerful probe of physics at the highest energy scales. Supersymmetric theories with conserved R-parity contain Planck-suppressed dimension 5 operators that give important contributions to nucleon decay. These operators are likely controlled by flavor physics, which means current and near future proton decay experiments might yield clues about the fermion mass spectrum. I present a thorough analysis of nucleon partial lifetimes in supersymmetric one-flavon Froggatt-Nielsen models with a single U(1)_X family symmetry which is responsible for the fermionic mass spectrum as well as forbidding R-parity violating interactions. Many of the models naturally lead to nucleon decay near present limits without any reference to grand unification.Comment: 6 pages, 3 figures, talk given at PASCOS '04, to appear in the proceeding

Incomplete markets and fertilizer use : evidence from Ethiopia

While the economic returns to using chemical fertilizer in Africa can be large, application rates are low. This study explores whether this is due to missing and imperfect markets. Results based on a panel survey of Ethiopian farmers suggest that while fertilizer markets are not altogether missing in rural Ethiopia, high transport costs, unfavorable climate, price risk, and illiteracy present formidable hurdles to farmer participation. Moreover, the combination of factors that promote or impede effective fertilizer markets differs among locations, making it difficult to find a single production technology that is uniformly profitable -- perhaps explaining the inconsistency between field studies finding large returns to fertilizer use in Ethiopia and survey-based studies finding fertilizer use to be uneconomic. The results suggest that households with greater stores of wealth, human capital and authority can overcome these hurdles. The finding offers some encouragement, but also implies a self-enforcing link between low agricultural productivity and poverty, since low-asset households are less able to overcome these problems. The study suggests that the provision of extension services can be effective and that lowering transport costs can raise the intensity of fertilizer use by lowering the cost of fertilizer and boosting the farmgate value of output.Climate Change and Agriculture,Fertilizers,Crops&Crop Management Systems,Access to Finance,Fertilizers&Agricultural Chemicals Industry

Multiscale methods for problems with complex geometry

We propose a multiscale method for elliptic problems on complex domains, e.g. domains with cracks or complicated boundary. For local singularities this paper also offers a discrete alternative to enrichment techniques such as XFEM. We construct corrected coarse test and trail spaces which takes the fine scale features of the computational domain into account. The corrections only need to be computed in regions surrounding fine scale geometric features. We achieve linear convergence rate in energy norm for the multiscale solution. Moreover, the conditioning of the resulting matrices is not affected by the way the domain boundary cuts the coarse elements in the background mesh. The analytical findings are verified in a series of numerical experiments

Valuing a Beach Day with a Repeated Nested Logit Model of Participation, Site Choice, and Stochastic Time Value

Beach recreation values are often needed by policy-makers and resource managers to efficiently manage coastal resources, especially in popular coastal areas like Southern California. This article presents welfare values derived from random utility maximization-based recreation demand models that explain an individual’s decisions about whether or not to visit a beach and which beach to visit. The models utilize labor market decisions to reveal each individual’s opportunity cost of recreation time. The value of having access to the beach in San Diego County is estimated to be between $21 and$23 per day.Recreation demand, repeated nested logit, labor supply, opportunity cost of leisure, time, beach recreation., Demand and Price Analysis, Environmental Economics and Policy, Institutional and Behavioral Economics, Q26, J22, Q51.,

Yesterday\u27s Technology, Tomorrow: How the Government\u27s Treatment of Intellectual Property Prevents Soldiers from Receiving the Best Tools to Complete Their Mission, 7 J. Marshall Rev. Intell. Prop. L. 171 (2007)

The Department of Defense is currently entrenched in a procurement system that does not respect the intellectual property of its contractors. This, in turn, has led to research and development firms’ increasing reluctance to contract with the Department of Defense. As a result of this reluctance, the United States has increasingly relied upon weapons systems that, in many cases, have not significantly evolved since the Vietnam War. In order to revive the United States’ flagging military technology sector Congress should look to 28 U.S.C. § 1498 and provisions of the Bayh-Dole Act in order to encourage the private sector’s creation of defense-oriented innovations. The proposed changes would merely extend a modicum of protection to Department of Defense contractors, something that they don’t currently have. The goal of this proposal is to encourage innovation in our laboratories in order to ensure victory on the battlefield and the safe return of American soldiers from overseas

Church Member Reactions to Religious Disaffiliation

Religious disaffiliation is a growing trend in the United States, with estimates of between 15% through 20% of Americans identifying that they have no religion and this rate is growing by roughly 1% each year. Nearly all research concerning religious disaffiliation has focused on the individuals who leave their faith, but little research has empirically explored how church members themselves react to the religious disaffiliation of individuals from their own religious community, as well as what factors potentially contribute to the formation of their attitudes and attributions towards religious disaffiliates. This study utilizes a Seventh-day Adventist sample’s reactions to a former Seventh-day Adventist pastor who disaffiliated and identified as an atheist. Before an understanding of the developmental mechanisms of these negative behaviors can take place, it is imperative to be able to identify and study the characteristics of the attitudes and attributions that drive these behaviors and the mechanisms that support them. Religious orientation has been studied extensively as a potential mechanism that shapes religious beliefs and drives religious behavior. The current study created a multi-item scale to identify negative attributions towards religious disaffiliates and explored its relationship to two empirically-established scales regarding religious orientation: Altemeyer and Hunsberger’s (2004) religious fundamentalism scale, and Batson and Schoenrade’s (1991b) religious quest scale. This study found a strong, positive association between negative attributions towards religious disaffiliates and religious fundamentalism, and a moderate negative association between negative attributions towards religious disaffiliates and a religious quest orientation. Although there is more work to be done, the current study proposes a scale for further research use and empirical validation

Food insecurity in veteran households: findings from nationally representative data

OBJECTIVE: The present study is the first to use nationally representative data to compare rates of food insecurity among households with veterans of the US Armed Forces and non-veteran households. DESIGN: We used data from the 2005-2013 waves of the Current Population Survey - Food Security Supplement to identify rates of food insecurity and very low food security in veteran and non-veteran households. We estimated the odds and probability of food insecurity in veteran and non-veteran households in uncontrolled and controlled models. We replicated these results after separating veteran households by their most recent period of service. We weighted models to create nationally representative estimates. SETTING: Nationally representative data from the 2005-2013 waves of the Current Population Survey - Food Security Supplement. SUBJECTS: US households (n 388 680). RESULTS: Uncontrolled models found much lower rates of food insecurity (8·4 %) and very low food security (3·3 %) among veteran households than in non-veteran households (14·4 % and 5·4 %, respectively), with particularly low rates among households with older veterans. After adjustment, average rates of food insecurity and very low food security were not significantly different for veteran households. However, the probability of food insecurity was significantly higher among some recent veterans and significantly lower for those who served during the Vietnam War. CONCLUSIONS: Although adjusting eliminated many differences between veteran and non-veteran households, veterans who served from 1975 and onwards may be at higher risk for food insecurity and should be the recipients of targeted outreach to improve nutritional outcomes

Gravitational radiation timescales for extreme mass ratio inspirals

The capture and inspiral of compact stellar masses into massive black holes is an important source of low-frequency gravitational waves (with frequencies of ~1-100mHz), such as those that might be detected by the planned Laser Interferometer Space Antenna (LISA). Simulations of stellar clusters designed to study this problem typically rely on simple treatments of the black hole encounter which neglect some important features of orbits around black holes, such as the minimum radii of stable, non-plunging orbits. Incorporating an accurate representation of the orbital dynamics near a black hole has been avoided due to the large computational overhead. This paper provides new, more accurate, expressions for the energy and angular momentum lost by a compact object during a parabolic encounter with a non-spinning black hole, and the subsequent inspiral lifetime. These results improve on the Keplerian expressions which are now commonly used and will allow efficient computational simulations to be performed that account for the relativistic nature of the spacetime around the central black hole in the system.Comment: 19 pages, 4 figures. Changed in response to referee's report. Accepted for publication in Astrophysical Journa