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A LOW WASTE VOLUME, FIRST CYCLE, 1A PUREX FLOW SHEET
The KPL No. 6, first-cycle Purex lA flow sheet is presented as an examaple of waste volume reduction through optimum solvent-extraction flow sheet design. Calculated on the basis of previous flow sheets, a 54 to 69% reduction of first-cycle waste storage volume is achieved by taming advantage of the extractability and reflux of nitric acid in TBP systems to provide adequate salting while minimizing the amount of acid going to waste. Although this report is concerned only with the first Purex cycle, the calculations are equally valid for the second U cycle, and the principles presented are applicable to similar nitnic acid-salted TBP systems. (auth
Bounds on second generation scalar leptoquarks from the anomalous magnetic moment of the muon
We calculate the contribution of second generation scalar leptoquarks to the
anomalous magnetic moment of the muon (AMMM). In the near future, E-821 at
Brookhaven will reduce the experimental error on this parameter to , an improvement of 20 over its current value.
With this new experimental limit we obtain a lower mass limit of
\ GeV for the second generation scalar leptoquark, when its
Yukawa-like coupling \ to quarks and leptons is taken to be
of the order of the electroweak coupling .Comment: 5 pages, plain tex, 1 figure (not included available under request
Nonlinear ion-acoustic (IA) waves driven in a cylindrically symmetric flow
By employing a self-similar, two-fluid MHD model in a cylindrical geometry,
we study the features of nonlinear ion-acoustic (IA) waves which propagate in
the direction of external magnetic field lines in space plasmas. Numerical
calculations not only expose the well-known three shapes of nonlinear
structures (sinusoidal, sawtooth, and spiky or bipolar) which are observed by
numerous satellites and simulated by models in a Cartesian geometry, but also
illustrate new results, such as, two reversely propagating nonlinear waves,
density dips and humps, diverging and converging electric shocks, etc. A case
study on Cluster satellite data is also introduced.Comment: accepted by AS
Strong laser fields as a probe for fundamental physics
Upcoming high-intensity laser systems will be able to probe the
quantum-induced nonlinear regime of electrodynamics. So far unobserved QED
phenomena such as the discovery of a nonlinear response of the quantum vacuum
to macroscopic electromagnetic fields can become accessible. In addition, such
laser systems provide for a flexible tool for investigating fundamental
physics. Primary goals consist in verifying so far unobserved QED phenomena.
Moreover, strong-field experiments can search for new light but weakly
interacting degrees of freedom and are thus complementary to accelerator-driven
experiments. I review recent developments in this field, focusing on photon
experiments in strong electromagnetic fields. The interaction of
particle-physics candidates with photons and external fields can be
parameterized by low-energy effective actions and typically predict
characteristic optical signatures. I perform first estimates of the accessible
new-physics parameter space of high-intensity laser facilities such as POLARIS
and ELI.Comment: 7 pages, Key Lecture at the ELI Workshop and School on "Fundamental
Physics with Ultra-High Fields", 9 September - 2 October 2008 at Frauenworth
Monastery, German
Overcoming the Impasse in Modern Economics
This document is the Accepted Manuscript version of the following article: Francesca Gagliardi, and David Gindis, 'Overcoming the Impasse in Modern Economics', Competition and Change, Vol. 15 (4): 336-42, November 2011, doi: 10.1179/102452911X13135903675732. Published by SAGE.Peer reviewe
Family Unification from Universality
A direct consequence of the occurrence of fermion families is the invariance
of currents under certain groups of (universality) transformations. We show how
these universality groups can themselves be used to find and study grand family
unification models. Identifying two independent - weak and strong -
universality groups and assuming that the grand unification group is SU(8N),
its subgroup respecting either weak or strong universality is shown to be G =
SU(2)xU(1)xSU(3). The fundamental representation of SU(8N) decomposes as N
families of leptons and quarks. In the G-invariant limit, all fermions are
left-handed. A mechanism for generating the correct number of right-handed
fermions with the correct couplings so as to give pure vector colour and
electromagnetic currents is exhibited. Universality is shown to result most
naturally from a preonic structure of fermions. In such a preonic picture there
are no ultraheavy gauge bosons and no anomaly or hierarchy problem.Comment: 30 page
Gauge and Scheme Dependence of Mixing Matrix Renormalization
We revisit the issue of mixing matrix renormalization in theories that
include Dirac or Majorana fermions. We show how a gauge-variant on-shell
renormalized mixing matrix can be related to a manifestly gauge-independent one
within a generalized scheme of renormalization. This
scheme-dependent relation is a consequence of the fact that in any scheme of
renormalization, the gauge-dependent part of the mixing-matrix counterterm is
ultra-violet safe and has a pure dispersive form. Employing the unitarity
properties of the theory, we can successfully utilize the afore-mentioned
scheme-dependent relation to preserve basic global or local symmetries of the
bare Lagrangian through the entire process of renormalization. As an immediate
application of our study, we derive the gauge-independent renormalization-group
equations of mixing matrices in a minimal extension of the Standard Model with
isosinglet neutrinos.Comment: 31 pages, LaTeX, uses axodraw.st
Thermal leptogenesis in a model with mass varying neutrinos
In this paper we consider the possibility of neutrino mass varying during the
evolution of the Universe and study its implications on leptogenesis.
Specifically, we take the minimal seesaw model of neutrino masses and introduce
a coupling between the right-handed neutrinos and the dark energy scalar field,
the Quintessence. In our model, the right-handed neutrino masses change as the
Quintessence scalar evolves. We then examine in detail the parameter space of
this model allowed by the observed baryon number asymmetry. Our results show
that it is possible to lower the reheating temperature in this scenario in
comparison with the case that the neutrino masses are unchanged, which helps
solve the gravitino problem. Furthermore, a degenerate neutrino mass patten
with larger than the upper limit given in the minimal leptogenesis
scenario is permitted.Comment: 18 pages, 7 figures, version to appear in PR
Age-related trajectories of social cognition in youth at clinical high risk for psychosis: An exploratory study
Background: Clinical high risk (CHR) status is characterized by impairments in social cognition, but questions remain concerning their stability over development. In cross-sectional analysis of a large naturalistic sample, the current study examined whether those at CHR status show deviant trajectories for age-related change in social cognitive ability, and whether these trajectories are influenced by treatment history. Method: Emotion perception (EP) and theory of mind (ToM) were assessed in 675 CHR and 263 healthy comparison (HC) participants aged 12–35. Age effects in CHR were modeled against HC age-expected performance. Prior medication status was tested for interactions with age. Results: CHR exhibited normal age trajectory for EP, but significantly lower slopes for ToM from age 17 onward. This effect was specific to stimuli exhibiting sarcasm and not to detection of lies. When treatment history was included in the model, age-trajectory appeared normal in CHR subjects previously prescribed both antipsychotics and antidepressant medication, although the blunted trajectory still characterized 80% of the sample. Discussion: Cross-sectional analyses suggested that blunting of ToM in CHR develops in adolescence, while EP abilities were diminished evenly across the age range. Exploratory analyses of treatment history suggested that ToM was not affected, however, in CHRs with lifetime histories of both antipsychotic and antidepressant medications. Reduction in age-expected ToM ability may impair the ability of individuals at CHR to meet social developmental challenges in adolescence. Medication effects on social cognition deserve further study
Lack of diagnostic pluripotentiality in patients at clinical high risk for psychosis: Specificity of comorbidity persistence and search for pluripotential subgroups
More than 20 years after the clinical high risk syndrome for psychosis (CHR) was first articulated, it remains controversial whether the CHR syndrome predicts onset of psychosis with diagnostic specificity or predicts pluripotential diagnostic outcomes. Recently, analyses of observational studies, however, have suggested that the CHR syndrome is not pluripotential for emergent diagnostic outcomes. The present report conducted additional analyses in previously reported samples to determine (1) whether comorbid disorders were more likely to persist in CHR patients compared to a comparison group of patients who responded to CHR recruitment efforts but did not meet criteria, termed help-seeking comparison subjects (HSC); and (2) whether clinically defined pluripotential CHR subgroups could be identified. All data were derived from 2 multisite studies in which DSM-IV structured diagnostic interviews were conducted at baseline and at 6-month intervals. Across samples we observed persistence of any nonpsychotic disorder in 80/147 CHR cases (54.4%) and in 48/84 HSC cases (57.1%, n.s.). Findings with persistence of anxiety, depressive, and bipolar disorders considered separately were similar. Efforts to discover pluripotential CHR subgroups were unsuccessful. These findings add additional support to the view that the CHR syndrome is not pluripotential for predicting various diagnostic outcomes but rather is specific for predicting emergent psychosis
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