391 research outputs found
Revisiting Deniability in Quantum Key Exchange via Covert Communication and Entanglement Distillation
We revisit the notion of deniability in quantum key exchange (QKE), a topic
that remains largely unexplored. In the only work on this subject by Donald
Beaver, it is argued that QKE is not necessarily deniable due to an
eavesdropping attack that limits key equivocation. We provide more insight into
the nature of this attack and how it extends to other constructions such as QKE
obtained from uncloneable encryption. We then adopt the framework for quantum
authenticated key exchange, developed by Mosca et al., and extend it to
introduce the notion of coercer-deniable QKE, formalized in terms of the
indistinguishability of real and fake coercer views. Next, we apply results
from a recent work by Arrazola and Scarani on covert quantum communication to
establish a connection between covert QKE and deniability. We propose DC-QKE, a
simple deniable covert QKE protocol, and prove its deniability via a reduction
to the security of covert QKE. Finally, we consider how entanglement
distillation can be used to enable information-theoretically deniable protocols
for QKE and tasks beyond key exchange.Comment: 16 pages, published in the proceedings of NordSec 201
Processing and Technology of Fruits and Vegetables, 1960
Tomato Variety Evaluation for Processing, 1961 / W. A. Gould, J. R. Geisman and Wade Schulte -- Evaluation of Sweet Corn Varieties for Processing / J. R. Geisman and W. A. Gould -- Small Fruit Variety Evaluation Studies for Freezing / D. R. Davis and H. L. Stammer -- Evaluation of Apples for Processing. I. Fruit Juice Blends / D. R. Davis and H. L. Stammer -- Evaluation of Apples for Processing. II. Canned Apple Slices / D. R. Davis and H. L. Stammer -- Evaluation of Apples for Processing. III. Frozen Apple Slices / D. R. Davis and H. L. Stammer -- Evaluation of Apples for Processing. IV. Frozen Fruit Pies / D. R. Davis and H. L. Stammer -- A Study of Several Varieties of Pumpkin and Squash for Canning and Freezing for Use in Pies / Robert H. Clayton, J. R. Geisman and W. A. Gould -- Factors Effecting the Consistency of Cream Style Corn / D. R. Davis and W. A. Gould -- The Objective Measurement of Tomato Juice Consistency / Robert Kluter and W. A. Gould -- A Method for the Detection of Drosophila Fly Eggs and Larvae in Tomato Products / J. R. Geisman and Winston D. Bash -- A Chemical Study of Flavor and Flavor Substances in Tomatoes / John Hal Johnson and W. A. Gould -- Tannin Content Effects Grape Juice Quality / D. R. Davis and H. L. Stammer -- pH Survey for Tomatoes in Ohio / W. D. Bash -- Flavor Studies with Sauerkraut / J. R. Geisman, S. S. Verma and W. A. Gould -- The Effect of Fill Weight on Drained Weight of Canned Tomatoes / Wade A. Schulte and W. A. Gould -- A New Method for the Manufacture of Apple Sirup / M. P. Baldauf, D. R. Davis and H. L. Stammer -- Studies on Color Retention in Canned R.T.P. Cherries / D. R. Davis and H. L. Stammer -- Clumping Studies in Canned Blueberries / D. R. Davis and H. L. Stammer -- Infra-red Peeling Studies. I. Apples. / L. Lafferty and W. A. Gould -- Infra-red Peeling Studies. II. Tomatoes. / W. A. Gould, Richard Leiss and Donall Streets -- The Effect of Water Holding Times and Temperatures on Quality of Tomatoes / Richard Leiss, Ernest Anderson and W. A. Gould -- Quality Attributes of Sweet Potatoes - Glass Packed / Donald A. Giesser and W. A. Gould -- A Study of Some of the Factors Effecting the Efficiency of Washing of Fruits and Vegetables. I. Tomatoes / W. A. Gould and J. R. Geisman -- A Study of Some of the Factors Effecting the Efficiency of Washing of Fruits and Vegetables. II. Sweet Corn / J. R. Geisman and W. A. Gould -- A Study of Alpha-keto Acids, Amino Acids, and Citric Acid in Eight Tomato Varieties, and Their Changes During Processing / Mokhtar M. Hamdy and W. A. Goul
RHYTHM-AF: design of an international registry on cardioversion of atrial fibrillation and characteristics of participating centers
BACKGROUND Atrial fibrillation is a serious public health problem posing a considerable burden to not only patients, but the healthcare environment due to high rates of morbidity, mortality, and medical resource utilization. There are limited data on the variation in treatment practice patterns across different countries, healthcare settings and the associated health outcomes. METHODS/DESIGN RHYTHM-AF was a prospective observational multinational study of management of recent onset atrial fibrillation patients considered for cardioversion designed to collect data on international treatment patterns and short term outcomes related to cardioversion. We present data collected in 10 countries between May 2010 and June 2011. Enrollment was ongoing in Italy and Brazil at the time of data analysis. Data were collected at the time of atrial fibrillation episode in all countries (Australia, Brazil, France, Germany, Italy, Netherlands, Poland, Spain, Sweden, United Kingdom), and cumulative follow-up data were collected at day 60 (±10) in all but Spain. Information on center characteristics, enrollment data, patient demographics, detail of atrial fibrillation episode, medical history, diagnostic procedures, acute treatment of atrial fibrillation, discharge information and the follow-up data on major events and rehospitalizations up to day 60 were collected. DISCUSSIN A total of 3940 patients were enrolled from 175 acute care centers. 70.5% of the centers were either academic (44%) or teaching (26%) hospitals with an overall median capacity of 510 beds. The sites were mostly specialized with anticoagulation clinics (65.9%), heart failure (75.1%) and hypertension clinics (60.1%) available. The RHYTHM-AF registry will provide insight into regional variability of antiarrhythmic and antithrombotic treatment of atrial fibrillation, the appropriateness of such treatments with respect to outcomes, and their cost-efficacy. Observations will help inform strategies to improve cardiovascular outcomes in patients with atrial fibrillation. TRIAL REGISTRATION Clinical trials NCT01119716Harry JGM Crijns, Lori D Bash, François Chazelle, Jean-Yves Le Heuzey, Thorsten Lewalter, Gregory YH Lip, Aldo P Maggioni, Alfonso MartĂn, Piotr Ponikowski, MĂ„rten Rosenqvist, Prashanthan Sanders, Mauricio Scanavacca, Alexandra A Bernhardt, Sreevalsa Unniachan, Hemant M Phatak and Anselm K Git
Central kinematics of the globular cluster NGC 2808: Upper limit on the mass of an intermediate-mass black hole
Globular clusters are an excellent laboratory for stellar population and
dynamical research. Recent studies have shown that these stellar systems are
not as simple as previously assumed. With multiple stellar populations as well
as outer rotation and mass segregation they turn out to exhibit high
complexity. This includes intermediate-mass black holes which are proposed to
sit at the centers of some massive globular clusters. Today's high angular
resolution ground based spectrographs allow velocity-dispersion measurements at
a spatial resolution comparable to the radius of influence for plausible IMBH
masses, and to detect changes in the inner velocity-dispersion profile.
Together with high quality photometric data from HST, it is possible to
constrain black-hole masses by their kinematic signatures. We determine the
central velocity-dispersion profile of the globular cluster NGC 2808 using
VLT/FLAMES spectroscopy. In combination with HST/ACS data our goal is to probe
whether this massive cluster hosts an intermediate-mass black hole at its
center and constrain the cluster mass to light ratio as well as its total mass.
We derive a velocity-dispersion profile from integral field spectroscopy in the
center and Fabry Perot data for larger radii. High resolution HST data are used
to obtain the surface brightness profile. Together, these data sets are
compared to dynamical models with varying parameters such as mass to light
ratio profiles and black-hole masses. Using analytical Jeans models in
combination with variable M/L profiles from N-body simulations we find that the
best fit model is a no black hole solution. After applying various Monte Carlo
simulations to estimate the uncertainties, we derive an upper limit of the back
hole mass of M_BH < 1 x 10^4 M_SUN (with 95 % confidence limits) and a global
mass-to-light ratio of M/L_V = (2.1 +- 0.2) M_SUN/L_SUN.Comment: 12 pages, 9 figures, 2 tables, accepted for publication in A&
Extrapolating SMBH correlations down the mass scale: the case for IMBHs in globular clusters
Empirical evidence for both stellar mass black holes M_bh<10^2 M_sun) and
supermassive black holes (SMBHs, M_bh>10^5 M_sun) is well established.
Moreover, every galaxy with a bulge appears to host a SMBH, whose mass is
correlated with the bulge mass, and even more strongly with the central stellar
velocity dispersion sigma_c, the `M-sigma' relation. On the other hand,
evidence for "intermediate-mass" black holes (IMBHs, with masses in the range
1^2 - 10^5 M_sun) is relatively sparse, with only a few mass measurements
reported in globular clusters (GCs), dwarf galaxies and low-mass AGNs. We
explore the question of whether globular clusters extend the M-sigma
relationship for galaxies to lower black hole masses and find that available
data for globular clusters are consistent with the extrapolation of this
relationship. We use this extrapolated M-sigma relationship to predict the
putative black hole masses of those globular clusters where existence of
central IMBH was proposed. We discuss how globular clusters can be used as a
constraint on theories making specific predictions for the low-mass end of the
M-sigma relation.Comment: 14 pages, 3 figures, accepted for publication in Astrophysics and
Space Science; fixed typos and a quote in Sec.
Single-epitope recognition imaging of native chromatin
© 2008 Wang et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution Licens
The spatial distribution of star and cluster formation in M51
Aims. We study the connection between spatially resolved star formation and
young star clusters across the disc of M51. Methods. We combine star cluster
data based on B, V, and I-band Hubble Space Telescope ACS imaging, together
with new WFPC2 U-band photometry to derive ages, masses, and extinctions of
1580 resolved star clusters using SSP models. This data is combined with data
on the spatially resolved star formation rates and gas surface densities, as
well as Halpha and 20cm radio-continuum (RC) emission, which allows us to study
the spatial correlations between star formation and star clusters. Two-point
autocorrelation functions are used to study the clustering of star clusters as
a function of spatial scale and age. Results. We find that the clustering of
star clusters among themselves decreases both with spatial scale and age,
consistent with hierarchical star formation. The slope of the autocorrelation
functions are consistent with projected fractal dimensions in the range of
1.2-1.6, which is similar to other galaxies, therefore suggesting that the
fractal dimension of hierarchical star formation is universal. Both star and
cluster formation peak at a galactocentric radius of 2.5 and 5 kpc, which we
tentatively attribute to the presence of the 4:1 resonance and the co-rotation
radius. The positions of the youngest (<10 Myr) star clusters show the
strongest correlation with the spiral arms, Halpha, and the RC emission, and
these correlations decrease with age. The azimuthal distribution of clusters in
terms of kinematic age away from the spiral arms indicates that the majority of
the clusters formed 5-20 Myr before their parental gas cloud reached the centre
of the spiral arm.Comment: 14 pages, 21 figures, accepted for publication in A&
Dietary behaviours in the context of nutrition transition : a systematic review and meta-analyses in two African countries
Objective:
To synthesise evidence of urban dietary behaviours (macronutrients, types of foods, dietary diversity and dietary practices) in two African countries in relation to postulated changes in the context of nutrition transition.
Design:
Systematic review and meta-analyses, including six online databases and grey literature, 1971â2018 (Protocol CRD42017067718).
Setting:
Urban Ghana and Kenya.
Participants:
Population-based studies of healthy adolescents and adults.
Results:
The forty-seven included studies encompassed 20 726 individuals plus 6526 households. Macronutrients were within WHO-recommended ranges: mean energy intake was 1867 kcal/d (95 % CI 1764, 1969) and the proportions of macronutrients were carbohydrate 61·2 % (58·4, 64·0), fat 25·3 % (22·8, 28·0) and protein 13·7 % (12·3, 15·1). The proportion of population consuming fruit and vegetables was 51·6 %; unhealthy foods, 29·4 %; and sugar-sweetened beverages (SSBs), 39·9 %. Two-thirds (68·8 %) consumed animal-source proteins. Dietary diversity scores were within the mid-range. Meal patterns were structured (typically three meals per day), with evidence lacking on snacking or eating out.
Conclusions:
Population-level diets fell within WHO macronutrient recommendations, were relatively diverse with structured meal patterns, but some indications of nutrition transition were apparent. The proportion of population consuming fruit and vegetables was low compared to healthy-eating recommendations, and consumption of SSBs was widespread. A paucity of evidence from 1971 to 2010 precluded a longitudinal analysis of nutrition transition. Evidence from these two countries indicates which aspects of dietary behaviours may be contributing to increasing overweight/obesity, namely a low proportion of population consuming fruit and vegetables and widespread consumption of SSBs. These are potential targets for promoting healthier diets
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