444 research outputs found
Old Bulloch Personalities
The sixth issue of Southern Folkways Journal Review contains poems handed down by three different Bulloch County families, a paper on the Salzburgers, an interview with Daisy Trapnell, an article on Bulloch County personality “Bitin’ Jake,” a letter concerning Isaac Chadburn Daniel, a query concerning the lives of John and Robert Dunwoody, and four sketches by Rita Turner Wall.https://digitalcommons.georgiasouthern.edu/bchs-pubs/1027/thumbnail.jp
Black Holes and the SYM Phase Diagram
Making combined use of the Matrix and Maldacena conjectures, the relation
between various thermodynamic transitions in super Yang-Mills (SYM) and
supergravity is clarified. The thermodynamic phase diagram of an object in DLCQ
M-theory in four and five non-compact space dimensions is constructed; matrix
strings, matrix black holes, and black -branes are among the various phases.
Critical manifolds are characterized by the principles of correspondence and
longitudinal localization, and a triple point is identified. The microscopic
dynamics of the Matrix string near two of the transitions is studied; we
identify a signature of black hole formation from SYM physics.Comment: 36 pages, latex; 6 eps figure
Black Holes and Massive Remnants
This paper revisits the conundrum faced when one attempts to understand the
dynamics of black hole formation and evaporation without abandoning unitary
evolution. Previous efforts to resolve this puzzle assume that information
escapes in corrections to the Hawking process, that an arbitrarily large amount
of information is transmitted by a planckian energy or contained in a
Planck-sized remnant, or that the information is lost to another universe. Each
of these possibilities has serious difficulties. This paper considers another
alternative: remnants that carry large amounts of information and whose size
and mass depend on their information content. The existence of such objects is
suggested by attempts to incorporate a Planck scale cutoff into physics. They
would greatly alter the late stages of the evaporation process. The main
drawback of this scenario is apparent acausal behavior behind the horizon.Comment: 16 pages + 3 Fig
The future burden of lung cancer attributable to current modifiable behaviours: a pooled study of seven Australian cohorts
BACKGROUND: Knowledge of preventable disease and differences in disease burden can inform public health action to improve health and health equity. We quantified the future lung cancer burden preventable by behavioural modifications across Australia. METHODS: We pooled seven Australian cohort studies (n = 367 058) and linked them to national registries to identify lung cancers and deaths. We estimated population attributable fractions and their 95% confidence intervals (CIs) for modifiable risk factors, using risk estimates from the cohort data and risk factor exposure distribution from contemporary national health surveys. RESULTS: During the first 10-year follow-up, there were 2025 incident lung cancers and 20 349 deaths. Stopping current smoking could prevent 53.7% (95% CI, 50.0-57.2%) of lung cancers over 40 years and 18.3% (11.0-25.1%) in 10 years. The smoking-attributable burden is highest in males, those who smoke <20 cigarettes per day, are <75 years of age, unmarried, of lower educational attainment, live in remote areas or are healthy weight. Increasing physical activity and fruit consumption, if causal, could prevent 15.6% (6.9-23.4%) and 7.5% (1.3-13.3%) of the lung cancer burden, respectively. Jointly, the three behaviour modifications could prevent up to 63.0% (58.0-67.5%) of lung cancers in 40 years, and 31.2% (20.9-40.1%) or 43 300 cancers in 10 years. The preventable burden is highest among those with multiple risk factors. CONCLUSIONS: Smoking remains responsible for the highest burden of lung cancer in Australia. The uneven burden distribution distinguishes subgroups that could benefit the most from activities to control the world's deadliest cancer
Priority sites for wildfowl conservation in Mexico
A set of priority sites for wildfowl conservation in Mexico was determined using contemporary count data (1991–2000) from the U.S. Fish & Wildlife Service mid-winter surveys. We used a complementarity approach implemented through linear integer programming that addresses particular conservation concerns for every species included in the analysis and large fluctuations in numbers through time.
A set of 31 priority sites was identified, which held more than 69% of the mid-winter count total in Mexico during all surveyed years. Six sites were in the northern highlands, 12 in the central highlands, six on the Gulf of Mexico coast and seven on the upper Pacific coast. Twenty-two sites from the priority set have previously been identified as qualifying for designation as wetlands of international importance under the Ramsar Convention and 20 sites are classified as Important Areas for Bird Conservation in Mexico. The information presented here provides an accountable, spatially-explicit, numerical basis for ongoing conservation planning efforts in Mexico, which can be used to improve existing wildfowl conservation networks in the country and can also be useful for conservation planning exercises elsewhere
The Particle Physics Reach of High-Energy Neutrino Astronomy
We discuss the prospects for high-energy neutrino astronomy to study particle
physics in the energy regime comparable to and beyond that obtainable at the
current and planned colliders. We describe the various signatures of
high-energy cosmic neutrinos expected in both neutrino telescopes and air
shower experiments and discuss these measurements within the context of
theoretical models with a quantum gravity or string scale near a TeV,
supersymmetry and scenarios with interactions induced by electroweak
instantons. We attempt to access the particle physics reach of these
experiments.Comment: Mini-review article for New Journal of Physics, "Focus on Neutrinos"
issue. 27 pages, 11 figure
WHAT GOOD IS WEALTH WITHOUT HEALTH? THE EFFECT OF HEALTH ON THE MARGINAL UTILITY OF CONSUMPTION
We estimate how the marginal utility of consumption varies with health. To do so, we develop a simple model in which the impact of health on the marginal utility of consumption can be estimated from data on permanent income, health, and utility proxies. We estimate the model using the Health and Retirement Study's panel data on the elderly and near-elderly, and proxy for utility with measures of subjective well-being. Across a wide range of alternative specifications and assumptions, we find that the marginal utility of consumption declines as health deteriorates, and we are able to clearly reject the null of no state dependence. Our point estimates indicate that a one-standard-deviation increase in the number of chronic diseases is associated with a 10%–25% decline in the marginal utility of consumption relative to this marginal utility when the individual has no chronic diseases. We present some simple, illustrative calibration results that suggest that state dependence of the magnitude we estimate can have a substantial effect on important economic problems such as the optimal level of health insurance benefits and the optimal level of life-cycle savings.United States. Social Security Administration (National Bureau of Economic Research Grant 10-P-98363-1-05)National Institute on Aging (Grant T32-AG000186
Unique, non‐Earthlike, meteoritic ion behavior in upper atmosphere of Mars
Interplanetary dust particles have long been expected to produce permanent ionospheric metal ion layers at Mars, as on Earth, but the two environments are so different that uncertainty existed as to whether terrestrial-established understanding would apply to Mars. The Mars Atmosphere and Volatile EvolutioN (MAVEN) mission made the first in situ detection of the continuous presence of Na+, Mg+, and Fe+ at Mars and indeed revealed non-Earthlike features/processes. There is no separation of the light Mg+ and the heavy Fe+ with increasing altitude as expected for gravity control. The metal ions are well-mixed with the neutral atmosphere at altitudes where no mixing process is expected. Isolated metal ion layers mimicking Earth's sporadic E layers occur despite the lack of a strong magnetic field as required at Earth. Further, the metal ion distributions are coherent enough to always show atmospheric gravity wave signatures. All features and processes are unique to Mars
The entropy of black holes: a primer
After recalling the definition of black holes, and reviewing their energetics
and their classical thermodynamics, one expounds the conjecture of Bekenstein,
attributing an entropy to black holes, and the calculation by Hawking of the
semi-classical radiation spectrum of a black hole, involving a thermal
(Planckian) factor. One then discusses the attempts to interpret the black-hole
entropy as the logarithm of the number of quantum micro-states of a macroscopic
black hole, with particular emphasis on results obtained within string theory.
After mentioning the (technically cleaner, but conceptually more intricate)
case of supersymmetric (BPS) black holes and the corresponding counting of the
degeneracy of Dirichlet-brane systems, one discusses in some detail the
``correspondence'' between massive string states and non-supersymmetric
Schwarzschild black holes.Comment: 51 pages, 4 figures, talk given at the "Poincare seminar" (Paris, 6
December 2003), to appear in Poincare Seminar 2003 (Birkhauser
The burden of cancer attributable to modifiable risk factors: the Australian cancer-PAF cohort consortium
Purpose: To estimate the Australian cancer burden attributable to lifestyle-related risk factors and their combinations using a novel population attributable fraction (PAF) method that accounts for competing risk of death, risk factor interdependence and statistical uncertainty. Participants: 365 173 adults from seven Australian cohort studies. We linked pooled harmonised individual participant cohort data with population-based cancer and death registries to estimate exposure-cancer and exposure-death associations. Current Australian exposure prevalence was estimated from representative external sources. To illustrate the utility of the new PAF method, we calculated fractions of cancers causally related to body fatness or both tobacco and alcohol consumption avoidable in the next 10 years by risk factor modifications, comparing them with fractions produced by traditional PAF methods. Findings to date: Over 10 years of follow-up, we observed 27 483 incident cancers and 22 078 deaths. Of cancers related to body fatness (n=9258), 13% (95% CI 11% to 16%) could be avoided if those currently overweight or obese had body mass index of 18.5-24.9 kg/m2. Of cancers causally related to both tobacco and alcohol (n=4283), current or former smoking explains 13% (11% to 16%) and consuming more than two alcoholic drinks per day explains 6% (5% to 8%). The two factors combined explain 16% (13% to 19%): 26% (21% to 30%) in men and 8% (4% to 11%) in women. Corresponding estimates using the traditional PAF method were 20%, 31% and 10%. Our PAF estimates translate to 74 000 avoidable body fatness-related cancers and 40 000 avoidable tobacco- and alcohol-related cancers in Australia over the next 10 years (2017-2026). Traditional PAF methods not accounting for competing risk of death and interdependence of risk factors may overestimate PAFs and avoidable cancers. Future plans: We will rank the most important causal factors and their combinations for a spectrum of cancers and inform cancer control activities.Maria E Arriaga, Claire M Vajdic, Karen Canfell, Robert MacInnis, Peter Hull, Dianna J Magliano, Emily Banks, Graham G Giles, Robert G Cumming, Julie E Byles, Anne W Taylor, Jonathan E Shaw, Kay Price, Vasant Hirani, Paul Mitchell, Barbara-Ann Adelstein, Maarit A Laaksone
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