2,943 research outputs found
Nonlocal lattice fermion models on the 2d torus
Abelian fermion models described by the SLAC action are considered on a
finite 2d lattice. It is shown that modification of these models by introducing
additional Pauli - Villars regularization supresses nonlocal effects and
provides agreement with the continuum results in vectorial U(1) models. In the
case of chiral fermions the phase of the determinant differs from the continuum
one.Comment: 16 pages, LaTeX, 5 eps figures, uses epsf.sty, rotate.st
Old and New Fields on Super Riemann Surfaces
The ``new fields" or ``superconformal functions" on super Riemann
surfaces introduced recently by Rogers and Langer are shown to coincide with
the Abelian differentials (plus constants), viewed as a subset of the functions
on the associated super Riemann surface. We confirm that, as originally
defined, they do not form a super vector space.Comment: 9 pages, LaTex. Published version: minor changes for clarity, two new
reference
Analysis of airborne Doppler lidar, Doppler radar and tall tower measurements of atmospheric flows in quiescent and stormy weather
The first experiment to combine airborne Doppler Lidar and ground-based dual Doppler Radar measurements of wind to detail the lower tropospheric flows in quiescent and stormy weather was conducted in central Oklahoma during four days in June-July 1981. Data from these unique remote sensing instruments, coupled with data from conventional in-situ facilities, i.e., 500-m meteorological tower, rawinsonde, and surface based sensors, were analyzed to enhance understanding of wind, waves and turbulence. The purposes of the study were to: (1) compare winds mapped by ground-based dual Doppler radars, airborne Doppler lidar, and anemometers on a tower; (2) compare measured atmospheric boundary layer flow with flows predicted by theoretical models; (3) investigate the kinematic structure of air mass boundaries that precede the development of severe storms; and (4) study the kinematic structure of thunderstorm phenomena (downdrafts, gust fronts, etc.) that produce wind shear and turbulence hazardous to aircraft operations. The report consists of three parts: Part 1, Intercomparison of Wind Data from Airborne Lidar, Ground-Based Radars and Instrumented 444 m Tower; Part 2, The Structure of the Convective Atmospheric Boundary Layer as Revealed by Lidar and Doppler Radars; and Part 3, Doppler Lidar Observations in Thunderstorm Environments
Technical and economic prospects for the site implementation of a gravitational water vortex power plant in Nepal
On the Monadic Second-Order Transduction Hierarchy
We compare classes of finite relational structures via monadic second-order
transductions. More precisely, we study the preorder where we set C \subseteq K
if, and only if, there exists a transduction {\tau} such that
C\subseteq{\tau}(K). If we only consider classes of incidence structures we can
completely describe the resulting hierarchy. It is linear of order type
{\omega}+3. Each level can be characterised in terms of a suitable variant of
tree-width. Canonical representatives of the various levels are: the class of
all trees of height n, for each n \in N, of all paths, of all trees, and of all
grids
The Monetary Transmission Mechanism
Several articles have recently questioned the "money view" of the monetary transmission mechanism and have offered an alternative "credit view". We argue that the money view has been incompletely presented in much of the literature and in almost all textbooks on Macroeconomics and Money and Banking. A distinction between the two views is unnecessary if one presents the money view correctly. A change in the money supply can affect income both directly and indirectly through what we call the "cash balance effect", which has other aspects than the wealth aspect that Patinkin emphasizes in discussing his "real-balance effect."Credit; Macroeconomics; Monetary; Money Supply; Money; Supply
Thermal Fluctuations of Elastic Filaments with Spontaneous Curvature and Torsion
We study the effects of thermal flucutations on thin elastic filaments with
spontaneous curvature and torsion. We derive analytical expressions for the
orientational correlation functions and for the persistence length of helices,
and find that this length varies non-monotonically with the strength of thermal
fluctuations. In the weak fluctuation regime, the persistence length of a
spontaneously twisted helix has three resonance peaks as a function of the
twist rate. In the limit of strong fluctuations, all memory of the helical
shape is lost.Comment: 1 figur
Examining the role of participant and study partner report in widely-used classification approaches of mild cognitive impairment in demographically-diverse community dwelling individuals: results from the Einstein aging study
ObjectiveThe role of subjective cognitive concerns (SCC) as a diagnostic criterion for MCI remains uncertain and limits the development of a universally (or widely)-accepted MCI definition. The optimal MCI definition should define an at-risk state and accurately predict the development of incident dementia. Questions remain about operationalization of definitions of self- and informant-reported SCCs and their individual and joint associations with incident dementia.MethodsThe present study included Einstein Aging Study participants who were non-Hispanic White or Black, free of dementia at enrollment, had follow-up, and completed neuropsychological tests and self-reported SCC at enrollment to determine MCI status. Informant-reported SCC at baseline were assessed via the CERAD clinical history questionnaire. Self-reported SCC were measured using the CERAD, items from the EAS Health Self-Assessment, and the single memory item from the Geriatric Depression Scale. Cox proportional hazards models examined the association of different operationalizations of SCC with Petersen and Jak/Bondi MCI definitions on the risk of dementia, further controlling for age, sex, education, and race/ethnicity. Time-dependent sensitivity and specificity at specific time points for each definition, and Youden’s index were calculated as an accuracy measure. Cox proportional hazards models were also used to evaluate the associations of combinations of self- and informant-reported SCC with the risk of incident dementia.Results91% of the sample endorsed at least one SCC. Youden’s index showed that not including SCC in either Jak/Bondi or Petersen classifications had the best balance between sensitivity and specificity across follow-up. A subset of individuals with informants, on average, had a lower proportion of non-Hispanic Blacks and 94% endorsed at least one self-reported SCC. Both informant-reported and self-reported SCC were significantly associated with incident dementia.ConclusionOur findings suggest that the SCC criterion may not improve the predictive validity for dementia when included in widely-employed definitions of MCI. Consistent with some prior research, informant-reported SCC was more related to risk of incident dementia than self-reported SCC. Given that requiring informant report as a diagnostic criterion may unintentionally exclude health disparate groups, additional consideration is needed to determine how best to utilize informant-report in MCI diagnosis
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