270 research outputs found
Spatial, Temporal and Demographical Analysis of Gulf of Mexico Research Priorities, the Effect of the Deepwater Horizon Oil Spill
A set of twenty equally-weighted national ocean research priorities were define in 2007, but it was not clear if these priorities applied for the Gulf of Mexico. A series of three longitudinal surveys of people who conduct research, sponsor research or use research for professional or recreational purposes was released that focused on the twenty research priorities and asked people how they rated each. A convenience sampling method was employed, which suggests that the results are constrained to the survey respondents and should not be extrapolated to a larger population. More than 1,500 people completed the 2013 GMRP survey and 1,124 of them rated all twenty national research priorities and four ecosystem service valuation priorities. Survey respondents rated the majority of research priorities as “high” or “very high” priorities but indicated that the research priorities are not equally important in the Gulf of Mexico. In addition, several indicators influenced how they rated the research priorities in 2013. The survey respondent’s area of expertise or discipline had the greatest influence on how they rated the priorities. Research priorities were also rated differently based on respondent’s relationship to research, affiliation, and sub-region within the U.S. Gulf of Mexico. The categories that had the greatest differences compared to others include those that use research for recreational purposes and the business sector. Research sponsors had no difference in rating of research priorities between those that conduct research or use research for their profession. While comparing the same survey respondent’s ratings in 2007, 2010 and 2013 seven out of 60 (11.7%) combinations of the research priorities across the three survey years were significantly different. However, only two of the twenty research priorities were rated significantly different between 2007 and 2013. The regional events that occurred between 2007 and 2013 such as the Deepwater Horizon oil spill may have changed the importance of research priorities for survey respondents over a short time period, however it may not have significantly changed the importance of many of the research priorities at the end of the six-year time period. A follow-on survey in 2016 could compliment this longitudinal work
Direct evidence for the Maldacena conjecture for N=(8,8) super Yang-Mills theory in 1+1 dimensions
We solve N=(8,8) super Yang-Mills theory in 1+1 dimensions at strong coupling
to directly confirm the predictions of supergravity at weak coupling. We do our
calculations in the large-N_c approximation using Supersymmetric Discrete
Light-Cone Quantization with up to 3*10^{12} basis states. We calculate the
stress-energy correlator as a function of the separation
r and find that at intermediate values of r the correlator behaves as r^{-5} to
within errors as predicted by weak-coupling supergravity. We also present an
extension to significantly higher resolution of our earlier results for the
same correlator in the N=(2,2) theory and see that in this theory the
correlator has very different behavior at intermediate values of r.Comment: 12 pp., 6 figures, LaTe
Spectrum and thermodynamic properties of two-dimensional N=(1,1) super Yang-Mills theory with fundamental matter and a Chern-Simons term
We consider N=(1,1) super Yang-Mills theory in 1+1 dimensions with
fundamentals at large-N_c. A Chern-Simons term is included to give mass to the
adjoint partons. Using the spectrum of the theory, we calculate thermodynamic
properties of the system as a function of the temperature and the Yang-Mills
coupling. In the large-N_c limit there are two non-communicating sectors, the
glueball sector, which we presented previously, and the meson-like sector that
we present here. We find that the meson-like sector dominates the
thermodynamics. Like the glueball sector, the meson sector has a Hagedorn
temperature T_H, and we show that the Hagedorn temperature grows with the
coupling. We calculate the temperature and coupling dependence of the free
energy for temperatures below T_H. As expected, the free energy for weak
coupling and low temperature grows quadratically with the temperature. Also the
ratio of the free energies at strong coupling compared to weak coupling,
r_{s-w}, for low temperatures grows quadratically with T. In addition, our data
suggest that r_{s-w} tends to zero in the continuum limit at low temperatures.Comment: 34 p
Effects of a fundamental mass term in two-dimensional super Yang-Mills theory
We show that adding a vacuum expectation value to a gauge field left over
from a dimensional reduction of three-dimensional pure supersymmetric
Yang-Mills theory generates mass terms for the fundamental fields in the
two-dimensional theory while supersymmetry stays intact. This is similar to the
adjoint mass term that is generated by a Chern-Simons term in this theory. We
study the spectrum of the two-dimensional theory as a function of the vacuum
expectation value and of the Chern-Simons coupling. Apart from some symmetry
issues a straightforward picture arises. We show that at least one massless
state exists if the Chern-Simons coupling vanishes. The numerical spectrum
separates into (almost) massless and very heavy states as the Chern-Simons
coupling grows. We present evidence that the gap survives the continuum limit.
We display structure functions and other properties of some of the bound
states.Comment: 17 pp., 10 figs; substantially revised version to be published in
Phys. Rev.
Use of Economic Analysis in Fraud on the Market Cases
In 1988, in Basic, Inc. v. Levinson,1 (Basic), the United States Supreme Court adopted the fraud on the market theory in order to create a presumption of reliance in a Security & Exchange Commissions Rule 10(b) securities fraud case. This article first explains the economic and legal background behind the fraud on the market presumption. Then, the landmark case of Basic is examined for guidance in applying the presumption and proving defenses to that presumption. Lastly, it is shown how economic analysis can be used in proving or disproving fraud on the market, including an empirical study of the events in Basic. The Court\u27s decision in Basic invites the use of economic/financial analysis, without recognition or guidance concerning that use. This article illustrates the importance of financial analysis in pursuing and defending a securities fraud case based on the fraud on the market presumption
Use of Economic Analysis in Fraud on the Market Cases
In 1988, in Basic, Inc. v. Levinson,1 (Basic), the United States Supreme Court adopted the fraud on the market theory in order to create a presumption of reliance in a Security & Exchange Commissions Rule 10(b) securities fraud case. This article first explains the economic and legal background behind the fraud on the market presumption. Then, the landmark case of Basic is examined for guidance in applying the presumption and proving defenses to that presumption. Lastly, it is shown how economic analysis can be used in proving or disproving fraud on the market, including an empirical study of the events in Basic. The Court\u27s decision in Basic invites the use of economic/financial analysis, without recognition or guidance concerning that use. This article illustrates the importance of financial analysis in pursuing and defending a securities fraud case based on the fraud on the market presumption
The Warwick-Edinburgh Mental Well-being Scale (WEMWBS) : development and UK validation
Background
There is increasing international interest in the concept of mental well-being and its contribution to all aspects of human life. Demand for instruments to monitor mental well-being at a population level and evaluate mental health promotion initiatives is growing. This article describes the development and validation of a new scale, comprised only of positively worded items relating to different aspects of positive mental health: the Warwick-Edinburgh Mental Well-Being Scale (WEMWBS).
Methods
WEMWBS was developed by an expert panel drawing on current academic literature, qualitative research with focus groups, and psychometric testing of an existing scale. It was validated on a student and representative population sample. Content validity was assessed by reviewing the frequency of complete responses and the distribution of responses to each item. Confirmatory factor analysis was used to test the hypothesis that the scale measured a single construct. Internal consistency was assessed using Cronbach's alpha. Criterion validity was explored in terms of correlations between WEMWBS and other scales and by testing whether the scale discriminated between population groups in line with pre-specified hypotheses. Test-retest reliability was assessed at one week using intra-class correlation coefficients. Susceptibility to bias was measured using the Balanced Inventory of Desired Responding.
Results
WEMWBS showed good content validity. Confirmatory factor analysis supported the single factor hypothesis. A Cronbach's alpha score of 0.89 (student sample) and 0.91 (population sample) suggests some item redundancy in the scale. WEMWBS showed high correlations with other mental health and well-being scales and lower correlations with scales measuring overall health. Its distribution was near normal and the scale did not show ceiling effects in a population sample. It discriminated between population groups in a way that is largely consistent with the results of other population surveys. Test-retest reliability at one week was high (0.83). Social desirability bias was lower or similar to that of other comparable scales.
Conclusion
WEMWBS is a measure of mental well-being focusing entirely on positive aspects of mental health. As a short and psychometrically robust scale, with no ceiling effects in a population sample, it offers promise as a tool for monitoring mental well-being at a population level. Whilst WEMWBS should appeal to those evaluating mental health promotion initiatives, it is important that the scale's sensitivity to change is established before it is recommended in this context
Efficacy of Two Raccoon Eviction Fluids
According to surveys of wildlife control operators (WCO), problems with raccoons (Procyon lotor) consistently rank among the top complaints for property owners. Among the more serious behaviors of female raccoons is their propensity to invade human-occupied structures to raise young. Distressed property owners frequently respond using lethal means, either on their own or through hiring WCOs. Even if live-captured and legally released, the handling of raccoons may result in injuries and potentially cause females to abandon young. Eviction fluids, developed in the early 1990s, are designed to smell like a male raccoon and therefore cause a nursing raccoon to leave the den with her young. Wildlife control operators use eviction fluid primarily to evict a female and her young from an inaccessible location. Though the precise formulas are not disclosed by manufacturers, the fluids consist of the glands and urine of male raccoons coupled with a preservative. We evaluated the efficacy of 2 raccoon eviction fluids to evict female raccoons with young from chimneys. Though our sample size was small (n =15), we found that eviction fluids merit further investigation as a viable non-lethal repellent for raccoons in human-occupied structures
N=(1,1) super Yang--Mills theory in 1+1 dimensions at finite temperature
We present a formulation of N=(1,1) super Yang-Mills theory in 1+1 dimensions
at finite temperature. The partition function is constructed by finding a
numerical approximation to the entire spectrum. We solve numerically for the
spectrum using Supersymmetric Discrete Light-Cone Quantization (SDLCQ) in the
large-N_c approximation and calculate the density of states. We find that the
density of states grows exponentially and the theory has a Hagedorn
temperature, which we extract. We find that the Hagedorn temperature at
infinite resolution is slightly less than one in units of (g^(2) N_c/pi)^(1/2).
We use the density of states to also calculate a standard set of thermodynamic
functions below the Hagedorn temperature. In this temperature range, we find
that the thermodynamics is dominated by the massless states of the theory.Comment: 16 pages, 8 eps figures, LaTe
Improved results for N=(2,2) super Yang-Mills theory using supersymmetric discrete light-cone quantization
We consider the (1+1)-dimensional super Yang--Mills theory
which is obtained by dimensionally reducing super Yang--Mills
theory in four dimension to two dimensions. We do our calculations in the
large- approximation using Supersymmetric Discrete Light Cone
Quantization. The objective is to calculate quantities that might be
investigated by researchers using other numerical methods. We present a
precision study of the low-mass spectrum and the stress-energy correlator
. We find that the mass gap of this theory closes as the
numerical resolution goes to infinity and that the correlator in the
intermediate region behaves like .Comment: 18 pages, 8 figure
- …