775 research outputs found
A generalization of the q-Saalschutz sum and the Burge transform
A generalization of the q-(Pfaff)-Saalschutz summation formula is proved.
This implies a generalization of the Burge transform, resulting in an
additional dimension of the ``Burge tree''. Limiting cases of our summation
formula imply the (higher-level) Bailey lemma, provide a new decomposition of
the q-multinomial coefficients, and can be used to prove the Lepowsky and Primc
formula for the A_1^{(1)} string functions.Comment: 18 pages, AMSLaTe
Challenges of Loss to Follow-up in Tuberculosis Research.
In studies evaluating methods for diagnosing tuberculosis (TB), follow-up to verify the presence or absence of active TB is crucial and high dropout rates may significantly affect the validity of the results. In a study assessing the diagnostic performance of the QuantiFERON®-TB Gold In-Tube test in TB suspect children in Tanzania, factors influencing patient adherence to attend follow-up examinations and reasons for not attending were examined. In 160 children who attended and 102 children who did not attend scheduled 2-month follow-up baseline health characteristics, demographic data and risk factors for not attending follow-up were determined. Qualitative interviews were used to understand patient and caretakers reasons for not returning for scheduled follow-up. Being treated for active tb in the dots program (OR: 4.14; 95% CI:1.99-8.62;p-value<0.001) and receiving money for the bus fare (OR:129; 95% CI 16->100;P-value<0.001) were positive predictors for attending follow-up at 2 months, and 21/85(25%) of children not attending scheduled follow-up had died. Interviews revealed that limited financial resources, i.e. lack of money for transportation and poor communication, were related to non-adherence. Patients lost to follow-up is a potential problem for TB research. Receiving money for transportation to the hospital and communication is crucial for adherence to follow-up conducted at a study facility. Strategies to ensure follow-up should be part of any study protocol
Actigraph Accelerometer-Defined Boundaries for Sedentary Behaviour and Physical Activity Intensities in 7 Year Old Children
Background: Accurate objective assessment of sedentary and physical activity behaviours during childhood is integral to the understanding of their relation to later health outcomes, as well as to documenting the frequency and distribution of physical activity within a population.Purpose: To calibrate the Actigraph GT1M accelerometer, using energy expenditure (EE) as the criterion measure, to define thresholds for sedentary behaviour and physical activity categories suitable for use in a large scale epidemiological study in young children.Methods: Accelerometer-based assessments of physical activity (counts per minute) were calibrated against EE measures (kcal.kg(-1).hr(-1)) obtained over a range of exercise intensities using a COSMED K4b(2) portable metabolic unit in 53 seven-year-old children. Children performed seven activities: lying down viewing television, sitting upright playing a computer game, slow walking, brisk walking, jogging, hopscotch and basketball. Threshold count values were established to identify sedentary behaviour and light, moderate and vigorous physical activity using linear discriminant analysis (LDA) and evaluated using receiver operating characteristic (ROC) curve analysis.Results: EE was significantly associated with counts for all non-sedentary activities with the exception of jogging. Threshold values for accelerometer counts (counts. minute(-1)) were = 3841 for light, moderate and vigorous physical activity respectively. The area under the ROC curves for discrimination of sedentary behaviour and vigorous activity were 0.98. Boundaries for light and moderate physical activity were less well defined (0.61 and 0.60 respectively). Sensitivity and specificity were higher for sedentary (99% and 97%) and vigorous (95% and 91%) than for light (60% and 83%) and moderate (61% and 76%) thresholds.Conclusion: The accelerometer cut points established in this study can be used to classify sedentary behaviour and to distinguish between light, moderate and vigorous physical activity in children of this age
Large scale analytic calculations in quantum field theories
We present a survey on the mathematical structure of zero- and single scale
quantities and the associated calculation methods and function spaces in higher
order perturbative calculations in relativistic renormalizable quantum field
theories.Comment: 25 pages Latex, 1 style fil
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The Sloan Digital Sky Survey quasar catalog: Tenth data release â&dagger
We present the Data Release 10 Quasar (DR10Q) catalog from the Baryon Oscillation Spectroscopic Survey (BOSS) of the Sloan Digital Sky
Survey III. The catalog includes all BOSS objects that were targeted as quasar candidates during the first 2.5 years of the survey and that are
confirmed as quasars via visual inspection of the spectra, have luminosities Mi[z = 2] < −20.5 (in a ΛCDMcosmology with H0 = 70 km s−1 Mpc−1,
ΩM = 0.3, and ΩΛ = 0.7), and either display at least one emission line with a full width at half maximum (FWHM) larger than 500 km s−1 or,
if not, have interesting/complex absorption features. The catalog also includes known quasars (mostly from SDSS-I and II) that were reobserved
by BOSS. The catalog contains 166 583 quasars (74 454 are new discoveries since SDSS-DR9) detected over 6373 deg2 with robust identification
and redshift measured by a combination of principal component eigenspectra. The number of quasars with z > 2.15 (117 668) is ∼5 times greater
than the number of z > 2.15 quasars known prior to BOSS. Redshifts and FWHMs are provided for the strongest emission lines (C iv, C iii,
Mg ii). The catalog identifies 16 461 broad absorption line quasars and gives their characteristics. For each object, the catalog presents five-band
(u, g, r, i, z) CCD-based photometry with typical accuracy of 0.03 mag and information on the optical morphology and selection method. The
catalog also contains X-ray, ultraviolet, near-infrared, and radio emission properties of the quasars, when available, from other large-area surveys.
The calibrated digital spectra cover the wavelength region 3600−10 500 Å at a spectral resolution in the range 1300 < R < 2500; the spectra can
be retrieved from the SDSS Catalog Archive Server. We also provide a supplemental list of an additional 2376 quasars that have been identified
among the galaxy targets of the SDSS-III/BOSS.I.P. received partial support from Center of Excellence in
Astrophysics and Associated Technologies (PFB 06). The French Participation
Group to SDSS-III was supported by the Agence Nationale de la Recherche
under contracts ANR-08-BLAN-0222 and ANR-12-BS05-0015. A.D.M. is
a research fellow of the Alexander von Humboldt Foundation of Germany
and was partially supported through NSF Grant 1211112 and NASA ADAP
award NNX12AE38G. Funding for SDSS-III has been provided by the
Alfred P. Sloan Foundation, the Participating Institutions, the National Science
Foundation, and the US Department of Energy Office of Science.This is the published version. It originally appeared in Astronomy and Astrophysics and is available online at http://www.aanda.org/articles/aa/abs/2014/03/aa22691-13/aa22691-13.html
Angular and Current-Target Correlations in Deep Inelastic Scattering at HERA
Correlations between charged particles in deep inelastic ep scattering have
been studied in the Breit frame with the ZEUS detector at HERA using an
integrated luminosity of 6.4 pb-1. Short-range correlations are analysed in
terms of the angular separation between current-region particles within a cone
centred around the virtual photon axis. Long-range correlations between the
current and target regions have also been measured. The data support
predictions for the scaling behaviour of the angular correlations at high Q2
and for anti-correlations between the current and target regions over a large
range in Q2 and in the Bjorken scaling variable x. Analytic QCD calculations
and Monte Carlo models correctly describe the trends of the data at high Q2,
but show quantitative discrepancies. The data show differences between the
correlations in deep inelastic scattering and e+e- annihilation.Comment: 26 pages including 10 figures (submitted to Eur. J. Phys. C
Plastisol Foaming Process. Decomposition of the Foaming Agent, Polymer Behavior in the Corresponding Temperature Range and Resulting Foam Properties
The decomposition of azodicarbonamide, used as foaming agent in PVC - plasticizer (1/1) plastisols was studied by DSC. Nineteen different plasticizers, all belonging to the ester family, two being polymeric (polyadipates), were compared. The temperature of maximum decomposition rate (in anisothermal regime at 5 K min-1 scanning rate), ranges between 434 and 452 K. The heat of decomposition ranges between 8.7 and 12.5 J g -1. Some trends of variation of these parameters appear significant and are discussed in terms of solvent (matrix) and viscosity effects on the decomposition reactions. The shear modulus at 1 Hz frequency was determined at the temperature of maximum rate of foaming agent decomposition, and differs significantly from a sample to another. The foam density was determined at ambient temperature and the volume fraction of bubbles was used as criterion to judge the efficiency of the foaming process. The results reveal the existence of an optimal shear modulus of the order of 2 kPa that corresponds roughly to plasticizer molar masses of the order of 450 ± 50 g mol-1. Heavier plasticizers, especially polymeric ones are too difficult to deform. Lighter plasticizers such as diethyl phthalate (DEP) deform too easily and presumably facilitate bubble collapse
A rare exception to Haldane's rule: are X chromosomes key to hybrid incompatibilities?
This work was funded by NERC (NE/G014906/1, NE/L011255/1, NE/I027800/1). Additional funding from the Orthopterists’ Society to PM is also gratefully acknowledged.The prevalence of Haldane’s rule suggests that sex chromosomes commonly have a key role in reproductive barriers and speciation. However, the majority of research on Haldane’s rule has been conducted in species with conventional sex determination systems (XY and ZW) and exceptions to the rule have been understudied. Here we test the role of X-linked incompatibilities in a rare exception to Haldane’s rule for female sterility in field cricket sister species (Teleogryllus oceanicus and T. commodus). Both have an XO sex determination system. Using three generations of crosses, we introgressed X chromosomes from each species onto different, mixed genomic backgrounds to test predictions about the fertility and viability of each cross type. We predicted that females with two different species X chromosomes would suffer reduced fertility and viability compared with females with two parental X chromosomes. However, we found no strong support for such X-linked incompatibilities. Our results preclude X–X incompatibilities and instead support an interchromosomal epistatic basis to hybrid female sterility. We discuss the broader implications of these findings, principally whether deviations from Haldane’s rule might be more prevalent in species without dimorphic sex chromosomes.PostprintPeer reviewe
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The Sloan Digital Sky Survey quasar catalog: Tenth data release â&dagger
We present the Data Release 10 Quasar (DR10Q) catalog from the Baryon Oscillation Spectroscopic Survey (BOSS) of the Sloan Digital Sky
Survey III. The catalog includes all BOSS objects that were targeted as quasar candidates during the first 2.5 years of the survey and that are
confirmed as quasars via visual inspection of the spectra, have luminosities Mi[z = 2] < −20.5 (in a ΛCDMcosmology with H0 = 70 km s−1 Mpc−1,
ΩM = 0.3, and ΩΛ = 0.7), and either display at least one emission line with a full width at half maximum (FWHM) larger than 500 km s−1 or,
if not, have interesting/complex absorption features. The catalog also includes known quasars (mostly from SDSS-I and II) that were reobserved
by BOSS. The catalog contains 166 583 quasars (74 454 are new discoveries since SDSS-DR9) detected over 6373 deg2 with robust identification
and redshift measured by a combination of principal component eigenspectra. The number of quasars with z > 2.15 (117 668) is ∼5 times greater
than the number of z > 2.15 quasars known prior to BOSS. Redshifts and FWHMs are provided for the strongest emission lines (C iv, C iii,
Mg ii). The catalog identifies 16 461 broad absorption line quasars and gives their characteristics. For each object, the catalog presents five-band
(u, g, r, i, z) CCD-based photometry with typical accuracy of 0.03 mag and information on the optical morphology and selection method. The
catalog also contains X-ray, ultraviolet, near-infrared, and radio emission properties of the quasars, when available, from other large-area surveys.
The calibrated digital spectra cover the wavelength region 3600−10 500 Å at a spectral resolution in the range 1300 < R < 2500; the spectra can
be retrieved from the SDSS Catalog Archive Server. We also provide a supplemental list of an additional 2376 quasars that have been identified
among the galaxy targets of the SDSS-III/BOSS.I.P. received partial support from Center of Excellence in
Astrophysics and Associated Technologies (PFB 06). The French Participation
Group to SDSS-III was supported by the Agence Nationale de la Recherche
under contracts ANR-08-BLAN-0222 and ANR-12-BS05-0015. A.D.M. is
a research fellow of the Alexander von Humboldt Foundation of Germany
and was partially supported through NSF Grant 1211112 and NASA ADAP
award NNX12AE38G. Funding for SDSS-III has been provided by the
Alfred P. Sloan Foundation, the Participating Institutions, the National Science
Foundation, and the US Department of Energy Office of Science.This is the published version. It originally appeared in Astronomy and Astrophysics and is available online at http://www.aanda.org/articles/aa/abs/2014/03/aa22691-13/aa22691-13.html
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