316 research outputs found
Comparing Wilson and Clover Quenched Spectroscopy with an Improved Gauge Action
We present results of quenched hadron spectroscopy comparing
\order(a) improved Wilson (Clover) fermions with conventional Wilson
fermions. The configurations were generated using an \order(a^2) improved
6-link pure gauge action at 's corresponding to lattice spacings
of , , , , and fm. We find evidence that
fermionic scaling violations are consistent with \order(a^2) for Clover and
\order(a) with a nonnegligible \order(a^2) term for standard Wilson
fermions. This latter mixed ansatz makes a reliable continuum extrapolation
problematic for Wilson fermions. We also find that the slope of the scaling
violations is roughly for both Wilson and Clover fermions.Comment: 3 pages latex with 2 postscript figures. Talk presented at
LATTICE96(spectrum
Quenched hadron spectroscopy using improved fermionic and gauge actions
We present results of quenched hadron spectroscopy using \order(a)
improved Wilson fermions. The configurations were generated using an
\order(a^2) improved 6-link pure gauge action at 's
corresponding to lattice spacings of , , , , and
fm. We find evidence that fermionic scaling violations are consistent with
\order(a^2) errors.Comment: 4 pages latex with 3 postscript figures. Corrected column heading in
tabl
Induction of Metastatic Gastric Cancer by Peroxisome Proliferator-Activated ReceptorÎŽ Activation
Peroxisome proliferator-activated receptorÎŽ (PPARÎŽ) regulates a multiplicity of physiological processes associated with glucose and lipid metabolism, inflammation, and proliferation. One or more of these processes likely create risk factors associated with the ability of PPARÎŽ agonists to promote tumorigenesis in some organs. In the present study, we describe a new gastric tumor mouse model that is dependent on the potent and highly selective PPARÎŽ agonist GW501516 following carcinogen administration. The progression of gastric tumorigenesis was rapid as determined by magnetic resonance imaging and resulted in highly metastatic squamous cell carcinomas of the forestomach within two months. Tumorigenesis was associated with gene expression signatures indicative of cell adhesion, invasion, inflammation, and metabolism. Increased PPARÎŽ expression in tumors correlated with increased PDK1, Akt, ÎČ-catenin, and S100A9 expression. The rapid development of metastatic gastric tumors in this model will be useful for evaluating preventive and therapeutic interventions in this disease
Automorphic Equivalence within Gapped Phases of Quantum Lattice Systems
Gapped ground states of quantum spin systems have been referred to in the
physics literature as being `in the same phase' if there exists a family of
Hamiltonians H(s), with finite range interactions depending continuously on , such that for each , H(s) has a non-vanishing gap above its
ground state and with the two initial states being the ground states of H(0)
and H(1), respectively. In this work, we give precise conditions under which
any two gapped ground states of a given quantum spin system that 'belong to the
same phase' are automorphically equivalent and show that this equivalence can
be implemented as a flow generated by an -dependent interaction which decays
faster than any power law (in fact, almost exponentially). The flow is
constructed using Hastings' 'quasi-adiabatic evolution' technique, of which we
give a proof extended to infinite-dimensional Hilbert spaces. In addition, we
derive a general result about the locality properties of the effect of
perturbations of the dynamics for quantum systems with a quasi-local structure
and prove that the flow, which we call the {\em spectral flow}, connecting the
gapped ground states in the same phase, satisfies a Lieb-Robinson bound. As a
result, we obtain that, in the thermodynamic limit, the spectral flow converges
to a co-cycle of automorphisms of the algebra of quasi-local observables of the
infinite spin system. This proves that the ground state phase structure is
preserved along the curve of models .Comment: Updated acknowledgments and new email address of S
Principles and principals: Do customer stewardship and agency control compete or complement when shaping frontline employee behavior?
This article introduces customer stewardship control (CSC) to the marketing field. This concept represents a frontline employee's felt ownership of and moral responsibility for customers' overall welfare. In two studies, the authors show that CSC is a more encompassing construct than customer orientation, which reflects a frontline employee's focus on meeting customers' needs. They provide evidence that the former is more potent in shaping in- and extra-role employee behaviors. Moreover, they highlight how CSC operates in conjunction with an organization's agency control system: Stewardship's positive influence on in- and extra-role behavior is weaker in the presence of high agency control. They offer actionable advice about how to solve the resulting managerial control dilemma. Finally, the authors show that CSC depends on drivers that reside at the individual level (employee relatedness), the team level (team competence), or both levels of aggregation (employee and team autonomy). These findings show how to effectively design a frontline employee's work environment to ensure optimal frontline performance
Zero temperature string breaking in lattice quantum chromodynamics
The separation of a heavy quark and antiquark pair leads to the formation of
a tube of flux, or "string", which should break in the presence of light
quark-antiquark pairs. This expected zero-temperature phenomenon has proven
elusive in simulations of lattice QCD. We study mixing between the string state
and the two-meson decay channel in QCD with two flavors of dynamical sea
quarks. We confirm that mixing is weak and find that it decreases at level
crossing. While our study does not show direct effects of internal quark loops,
our results, combined with unitarity, give clear confirmation of string
breaking.Comment: 20 pages, 7 figures. With small clarifications and two additions to
references. Submitted to Phys. Rev.
Topological susceptibility with the improved Asqtad action
As a test of the chiral properties of the improved Asqtad (staggered fermion)
action, we have been measuring the topological susceptibility as a function of
quark masses for 2 + 1 dynamical flavors. We report preliminary results, which
show reasonable agreement with leading order chiral perturbation theory for
lattice spacing less than 0.1 fm. The total topological charge, however, shows
strong persistence over Monte Carlo time.Comment: Lattice2002(algor
Deconfining Phase Transition as a Matrix Model of Renormalized Polyakov Loops
We discuss how to extract renormalized from bare Polyakov loops in SU(N)
lattice gauge theories at nonzero temperature in four spacetime dimensions.
Single loops in an irreducible representation are multiplicatively renormalized
without mixing, through a renormalization constant which depends upon both
representation and temperature. The values of renormalized loops in the four
lowest representations of SU(3) were measured numerically on small, coarse
lattices. We find that in magnitude, condensates for the sextet and octet loops
are approximately the square of the triplet loop. This agrees with a large
expansion, where factorization implies that the expectation values of loops in
adjoint and higher representations are just powers of fundamental and
anti-fundamental loops. For three colors, numerically the corrections to the
large relations are greatest for the sextet loop, ; these
represent corrections of for N=3. The values of the renormalized
triplet loop can be described by an SU(3) matrix model, with an effective
action dominated by the triplet loop. In several ways, the deconfining phase
transition for N=3 appears to be like that in the matrix model of
Gross and Witten.Comment: 24 pages, 7 figures; v2, 27 pages, 12 figures, extended discussion
for clarity, results unchange
Christianity as Public Religion::A Justification for using a Christian Sociological Approach for Studying the Social Scientific Aspects of Sport
The vast majority of social scientific studies of sport have been secular in nature and/or have tended to ignore the importance of studying the religious aspects of sport. In light of this, Shilling and Mellor (2014) have sought to encourage sociologists of sport not to divorce the âreligiousâ and the âsacredâ from their studies. In response to this call, the goal of the current essay is to explore how the conception of Christianity as âpublic religionâ can be utilised to help justify the use of a Christian sociological approach for studying the social scientific aspects of sport. After making a case for Christianity as public religion, we conclude that many of the sociological issues inherent in modern sport are an indirect result of its increasing secularisation and argue that this justifies the need for a Christian sociological approach. We encourage researchers to use the Bible, the tools of Christian theology and sociological concepts together, so to inform analyses of modern sport from a Christian perspective
The 10/66 Dementia Research Group's fully operationalised DSM-IV dementia computerized diagnostic algorithm, compared with the 10/66 dementia algorithm and a clinician diagnosis: a population validation study
<p>Abstract</p> <p>Background</p> <p>The criterion for dementia implicit in DSM-IV is widely used in research but not fully operationalised. The 10/66 Dementia Research Group sought to do this using assessments from their one phase dementia diagnostic research interview, and to validate the resulting algorithm in a population-based study in Cuba.</p> <p>Methods</p> <p>The criterion was operationalised as a computerised algorithm, applying clinical principles, based upon the 10/66 cognitive tests, clinical interview and informant reports; the Community Screening Instrument for Dementia, the CERAD 10 word list learning and animal naming tests, the Geriatric Mental State, and the History and Aetiology Schedule â Dementia Diagnosis and Subtype. This was validated in Cuba against a local clinician DSM-IV diagnosis and the 10/66 dementia diagnosis (originally calibrated probabilistically against clinician DSM-IV diagnoses in the 10/66 pilot study).</p> <p>Results</p> <p>The DSM-IV sub-criteria were plausibly distributed among clinically diagnosed dementia cases and controls. The clinician diagnoses agreed better with 10/66 dementia diagnosis than with the more conservative computerized DSM-IV algorithm. The DSM-IV algorithm was particularly likely to miss less severe dementia cases. Those with a 10/66 dementia diagnosis who did not meet the DSM-IV criterion were less cognitively and functionally impaired compared with the DSMIV confirmed cases, but still grossly impaired compared with those free of dementia.</p> <p>Conclusion</p> <p>The DSM-IV criterion, strictly applied, defines a narrow category of unambiguous dementia characterized by marked impairment. It may be specific but incompletely sensitive to clinically relevant cases. The 10/66 dementia diagnosis defines a broader category that may be more sensitive, identifying genuine cases beyond those defined by our DSM-IV algorithm, with relevance to the estimation of the population burden of this disorder.</p
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