7,934 research outputs found
Symposium: Law and the Correctional Process in Washington. Introduction
Of all the problems which face a public official there is none which is potentially more explosive than that of corrections. Under the best of circumstances there is always public uneasiness over the correctional system; under the worst conditions, corrections are a corrosive political issue which can destroy orderly, rational action by the public or by elected officials. Recently, debate seems to have centered around the controversy of rehabilitation versus punishment. An absolutist position has been taken by many of those who embrace either of the two concepts. Unfortunately, this focus (1) fails to look at corrections as a part of the total system for the administration of justice; and (2) overlooks the fact that different circumstances and different persons within the correctional system may require different treatment. [The author was the Governor of the State of Washington when this article was published.
Molecular Density Functional Theory for water with liquid-gas coexistence and correct pressure
The solvation of hydrophobic solutes in water is special because liquid and
gas are almost at coexistence. In the common hypernetted chain approximation to
integral equations, or equivalently in the homogenous reference fluid of
molecular density functional theory, coexistence is not taken into account.
Hydration structures and energies of nanometer-scale hydrophobic solutes are
thus incorrect. In this article, we propose a bridge functional that corrects
this thermodynamic inconsistency by introducing a metastable gas phase for the
homogeneous solvent. We show how this can be done by a third order expansion of
the functional around the bulk liquid density that imposes the right pressure
and the correct second order derivatives. Although this theory is not limited
to water, we apply it to study hydrophobic solvation in water at room
temperature and pressure and compare the results to all-atom simulations. With
this correction, molecular density functional theory gives, at a modest
computational cost, quantitative hydration free energies and structures of
small molecular solutes like n-alkanes, and of hard sphere solutes whose radii
range from angstroms to nanometers. The macroscopic liquid-gas surface tension
predicted by the theory is comparable to experiments. This theory gives an
alternative to the empirical hard sphere bridge correction used so far by
several authors.Comment: 18 pages, 6 figure
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Impact of New Laboratory Studies of N2O5 Hydrolysis on Global Model Budgets of Tropospheric Nitrogen Oxides, Ozone, and OH
We investigate the impact of new laboratory studies of N2O5 hydrolysis in aerosols on global model simulations of tropospheric chemistry. We use data from these new studies to parameterize the reaction probability (γN2O5) in the GEOS-CHEM global model as a function of local aerosol composition, temperature, and relative humidity. We find a much lower global mean γN2O5 (0.02) than commonly assumed in models (0.1). Relative to a model simulation assuming a uniform γN2O5 = 0.1, we find increases in mass-averaged tropospheric NOx, O3, and OH concentrations of 7%, 4%, and 8% respectively. The increases in NOx and O3 concentrations bring the GEOS-CHEM simulation in better agreement with climatological observations.Earth and Planetary Science
Arm-length stabilisation for interferometric gravitational-wave detectors using frequency-doubled auxiliary lasers
Residual motion of the arm cavity mirrors is expected to prove one of the
principal impediments to systematic lock acquisition in advanced
gravitational-wave interferometers. We present a technique which overcomes this
problem by employing auxiliary lasers at twice the fundamental measurement
frequency to pre-stabilise the arm cavities' lengths. Applying this approach,
we reduce the apparent length noise of a 1.3 m long, independently suspended
Fabry-Perot cavity to 30 pm rms and successfully transfer longitudinal control
of the system from the auxiliary laser to the measurement laser
Finite-Size-Scaling at the Jamming Transition: Corrections to Scaling and the Correlation Length Critical Exponent
We carry out a finite size scaling analysis of the jamming transition in
frictionless bi-disperse soft core disks in two dimensions. We consider two
different jamming protocols: (i) quench from random initial positions, and (ii)
quasistatic shearing. By considering the fraction of jammed states as a
function of packing fraction for systems with different numbers of particles,
we determine the spatial correlation length critical exponent ,
and show that corrections to scaling are crucial for analyzing the data. We
show that earlier numerical results yielding are due to the improper
neglect of these corrections.Comment: 5 pages, 4 figures -- slightly revised version as accepted for Phys.
Rev. E Rapid Communication
Genetic modifiers of cognitive maintenance among older adults.
ObjectiveIdentify genetic factors associated with cognitive maintenance in late life and assess their association with gray matter (GM) volume in brain networks affected in aging.MethodsWe conducted a genome-wide association study of ∼2.4 M markers to identify modifiers of cognitive trajectories in Caucasian participants (N = 7,328) from two population-based cohorts of non-demented elderly. Standardized measures of global cognitive function (z-scores) over 10 and 6 years were calculated among participants and mixed model regression was used to determine subject-specific cognitive slopes. "Cognitive maintenance" was defined as a change in slope of ≥ 0 and was compared with all cognitive decliners (slope < 0). In an independent cohort of cognitively normal older Caucasians adults (N = 122), top association findings were then used to create genetic scores to assess whether carrying more cognitive maintenance alleles was associated with greater GM volume in specific brain networks using voxel-based morphometry.ResultsThe most significant association was on chromosome 11 (rs7109806, P = 7.8 × 10(-8)) near RIC3. RIC3 modulates activity of α7 nicotinic acetylcholine receptors, which have been implicated in synaptic plasticity and beta-amyloid binding. In the neuroimaging cohort, carrying more cognitive maintenance alleles was associated with greater volume in the right executive control network (RECN; PFWE = 0.01).ConclusionsThese findings suggest that there may be genetic loci that promote healthy cognitive aging and that they may do so by conferring robustness to GM in the RECN. Future work is required to validate top candidate genes such as RIC3 for involvement in cognitive maintenance
Evidence for J and H-band excess in classical T Tauri stars and the implications for disk structure and estimated ages
We argue that classical T Tauri stars (cTTs) possess significant non-
photospheric excess in the J and H bands. We first show that normalizing the
spectral energy distributions (SEDs) of cTTs to the J-band leads to a poor fit
of the optical fluxes, while normalizing the SEDs to the Ic-band produces a
better fit to the optical bands and in many cases reveals the presence of a
considerable excess at J and H. NIR spectroscopic veiling measurements from the
literature support this result. We find that J and H-band excesses correlate
well with the K-band excess, and that the J-K and H-K colors of the excess
emission are consistent with that of a black body at the dust sublimation
temperature (~ 1500-2000 K). We propose that this near-IR excess originates at
a hot inner rim, analogous to those suggested to explain the near-IR bump in
the SEDs of Herbig Ae/Be stars. To test our hypothesis, we use the model
presented by Dullemond et al. (2001) to fit the photometry data between 0.5 um
and 24 um of 10 cTTs associated with the Chamaeleon II molecular cloud. The
models that best fit the data are those where the inner radius of the disk is
larger than expected for a rim in thermal equilibrium with the photospheric
radiation field alone. In particular, we find that large inner rims are
necessary to account for the mid infrared fluxes (3.6-8.0 um) obtained by the
Spitzer Space Telescope. Finally, we argue that deriving the stellar
luminosities of cTTs by making bolometric corrections to the J-band fluxes
systematically overestimates these luminosities. The overestimated luminosities
translate into underestimated ages when the stars are placed in the H-R
diagram. Thus, the results presented herein have important implications for the
dissipation timescale of inner accretion disks.Comment: 45 pages, 13 figure
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