1,070 research outputs found
Mixedness and entanglement for two-mode Gaussian states
We analytically exploit the two-mode Gaussian states nonunitary dynamics. We
show that in the zero temperature limit, entanglement sudden death (ESD) will
always occur for symmetric states (where initial single mode compression is
) provided the two mode squeezing satisfies We also give the analytical expressions for the time of ESD.
Finally, we show the relation between the single modes initial impurities and
the initial entanglement, where we exhibit that the later is suppressed by the
former.Comment: Accepted for publication in Optics Communication
Blood Pressure And Cardiac Autonomic Modulation At Rest, During Exercise And Recovery Time In The Young Overweight
This study aimed to assess the blood pressure (BP), cardiac autonomic modulation at rest, in physical exercise and in the recovery in untrained eutrophic (E) and overweight (O) youth. The body mass index (BMI), waist circumference (WC), systolic BP-SBP (E: 109.80 ± 10.05; O: 121.85 ± 6.98 mmHg) and diastolic BP DBP (E: 65.90 ± 7.28; O: 73.14 ± 12.22 mmHg) were higher in overweight and the heart rate recovery (%HRR) was lower as compared with E volunteers. The BMI was associated with SBP (r= 0.54), DBP (r= 0.65), load on the heart rate variability threshold-HRVT (r=-0.46), %HRR2' (r=-0.48) and %HRR 5âČ (r=-0.48), and WC was associated with SBP (r= 0.54), DBP (r= 0.64) and HRR2' (r=-0.49). The %HRR was associated to SBP, DBP and HRVT. In summary, the anthropometric variables, BP and cardiac autonomic modulation in the recovery are altered in overweight youth.221273
Maximally-localized Wannier functions for entangled energy bands
We present a method for obtaining well-localized Wannier-like functions (WFs)
for energy bands that are attached to or mixed with other bands. The present
scheme removes the limitation of the usual maximally-localized WFs method (N.
Marzari and D. Vanderbilt, Phys. Rev. B 56, 12847 (1997)) that the bands of
interest should form an isolated group, separated by gaps from higher and lower
bands everywhere in the Brillouin zone. An energy window encompassing N bands
of interest is specified by the user, and the algorithm then proceeds to
disentangle these from the remaining bands inside the window by filtering out
an optimally connected N-dimensional subspace. This is achieved by minimizing a
functional that measures the subspace dispersion across the Brillouin zone. The
maximally-localized WFs for the optimal subspace are then obtained via the
algorithm of Marzari and Vanderbilt. The method, which functions as a
postprocessing step using the output of conventional electronic-structure
codes, is applied to the s and d bands of copper, and to the valence and
low-lying conduction bands of silicon. For the low-lying nearly-free-electron
bands of copper we find WFs which are centered at the tetrahedral interstitial
sites, suggesting an alternative tight-binding parametrization.Comment: 13 pages, with 9 postscript figures embedded. Uses REVTEX and epsf
macro
Stability of the monoclinic phase in the ferroelectric perovskite PbZr(1-x)TixO3
Recent structural studies of ferroelectric PbZr(1-x)TixO3 (PZT) with x= 0.48,
have revealed a new monoclinic phase in the vicinity of the morphotropic phase
boundary (MPB), previously regarded as the the boundary separating the
rhombohedral and tetragonal regions of the PZT phase diagram. In the present
paper, the stability region of all three phases has been established from high
resolution synchrotron x-ray powder diffraction measurements on a series of
highly homogeneous samples with 0.42 <=x<= 0.52. At 20K the monoclinic phase is
stable in the range 0.46 <=x<= 0.51, and this range narrows as the temperature
is increased. A first-order phase transition from tetragonal to rhombohedral
symmetry is observed only for x= 0.45. The MPB, therefore, corresponds not to
the tetragonal-rhombohedral phase boundary, but instead to the boundary between
the tetragonal and monoclinic phases for 0.46 <=x<= 0.51. This result provides
important insight into the close relationship between the monoclinic phase and
the striking piezoelectric properties of PZT; in particular, investigations of
poled samples have shown that the monoclinic distortion is the origin of the
unusually high piezoelectric response of PZT.Comment: REVTeX file, 7 figures embedde
Evidence of Color Coherence Effects in W+jets Events from ppbar Collisions at sqrt(s) = 1.8 TeV
We report the results of a study of color coherence effects in ppbar
collisions based on data collected by the D0 detector during the 1994-1995 run
of the Fermilab Tevatron Collider, at a center of mass energy sqrt(s) = 1.8
TeV. Initial-to-final state color interference effects are studied by examining
particle distribution patterns in events with a W boson and at least one jet.
The data are compared to Monte Carlo simulations with different color coherence
implementations and to an analytic modified-leading-logarithm perturbative
calculation based on the local parton-hadron duality hypothesis.Comment: 13 pages, 6 figures. Submitted to Physics Letters
Limited compensation at the following meal for protein and energy intake at a lunch meal in healthy free-living older adults.
Various interventions have previously been found to increase protein intakes in older adults, but in free-living individuals, compensation for increased intakes at one meal may easily negate these effects resulting in limited long term benefit. This study investigated the impact of adding sauce to an older person's lunch meal on intakes at that meal, at the following meal and overall (lunch + evening meal). Using a repeated measures design, 52 participants consumed both a lunch meal with sauce and the same lunch meal without sauce on two separate occasions, and intake at this meal and at the following meal were measured. In all participants analysed together, the addition of sauce resulted in increased protein intakes at the lunch meal. Individual differences were also found, where for some individuals (n = 26), the addition of sauce resulted in significantly higher protein and energy intakes at the lunch meal (12.3 g protein, 381 kJ) and overall (11 g protein, 420 kJ), compared to the no-sauce condition, while for some individuals (n = 19), the sauce manipulation resulted in lower protein and energy intakes (lunch: 7 g protein, 297 kJ; overall: 7 g protein, 350 kJ). Compensation for earlier intakes was low (0-17%) for both groups. These findings demonstrate the possible value of adding sauce to an older person's meal for increasing intakes, and demonstrate a need for attention to individual differences. This study also confirms previous findings of limited compensation in older adults, but extends earlier studies to demonstrate limited compensation for the protein consumed in a complete meal in healthy older adults
Riverhood: political ecologies of socionature commoning and translocal struggles for water justice
Mega-damming, pollution and depletion endanger rivers worldwide. Meanwhile, modernist imaginaries of ordering âunruly waters and humansâ have become cornerstones of hydraulic-bureaucratic and capitalist development. They separate hydro/social worlds, sideline river-commons cultures, and deepen socio-environmental injustices. But myriad new water justice movements (NWJMs) proliferate: rooted, disruptive, transdisciplinary, multi-scalar coalitions that deploy alternative riverâsociety ontologies, bridge SouthâNorth divides, and translate river-enlivening practices from local to global and vice-versa. This paper's framework conceptualizes âriverhoodâ to engage with NWJMs and river commoning initiatives. We suggest four interrelated ontologies, situating river socionatures as arenas of material, social and symbolic co-production: âriver-as-ecosocietyâ, âriver-as-territoryâ, âriver-as-subjectâ, and âriver-as-movementâ
Measurement of the p-pbar -> Wgamma + X cross section at sqrt(s) = 1.96 TeV and WWgamma anomalous coupling limits
The WWgamma triple gauge boson coupling parameters are studied using p-pbar
-> l nu gamma + X (l = e,mu) events at sqrt(s) = 1.96 TeV. The data were
collected with the DO detector from an integrated luminosity of 162 pb^{-1}
delivered by the Fermilab Tevatron Collider. The cross section times branching
fraction for p-pbar -> W(gamma) + X -> l nu gamma + X with E_T^{gamma} > 8 GeV
and Delta R_{l gamma} > 0.7 is 14.8 +/- 1.6 (stat) +/- 1.0 (syst) +/- 1.0 (lum)
pb. The one-dimensional 95% confidence level limits on anomalous couplings are
-0.88 < Delta kappa_{gamma} < 0.96 and -0.20 < lambda_{gamma} < 0.20.Comment: Submitted to Phys. Rev. D Rapid Communication
Measurement of the ttbar Production Cross Section in ppbar Collisions at sqrt{s} = 1.96 TeV using Kinematic Characteristics of Lepton + Jets Events
We present a measurement of the top quark pair ttbar production cross section
in ppbar collisions at a center-of-mass energy of 1.96 TeV using 230 pb**{-1}
of data collected by the DO detector at the Fermilab Tevatron Collider. We
select events with one charged lepton (electron or muon), large missing
transverse energy, and at least four jets, and extract the ttbar content of the
sample based on the kinematic characteristics of the events. For a top quark
mass of 175 GeV, we measure sigma(ttbar) = 6.7 {+1.4-1.3} (stat) {+1.6- 1.1}
(syst) +/-0.4 (lumi) pb, in good agreement with the standard model prediction.Comment: submitted to Phys.Rev.Let
Measurement of the ttbar Production Cross Section in ppbar Collisions at sqrt(s)=1.96 TeV using Lepton + Jets Events with Lifetime b-tagging
We present a measurement of the top quark pair () production cross
section () in collisions at TeV
using 230 pb of data collected by the D0 experiment at the Fermilab
Tevatron Collider. We select events with one charged lepton (electron or muon),
missing transverse energy, and jets in the final state. We employ
lifetime-based b-jet identification techniques to further enhance the
purity of the selected sample. For a top quark mass of 175 GeV, we
measure pb, in
agreement with the standard model expectation.Comment: 7 pages, 2 figures, 3 tables Submitted to Phys.Rev.Let
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