638 research outputs found
Bulk correlation functions in 2D quantum gravity
We compute bulk 3- and 4-point tachyon correlators in the 2d Liouville
gravity with non-rational matter central charge c<1, following and comparing
two approaches. The continuous CFT approach exploits the action on the tachyons
of the ground ring generators deformed by Liouville and matter ``screening
charges''. A by-product general formula for the matter 3-point OPE structure
constants is derived. We also consider a ``diagonal'' CFT of 2D quantum
gravity, in which the degenerate fields are restricted to the diagonal of the
semi-infinite Kac table. The discrete formulation of the theory is a
generalization of the ADE string theories, in which the target space is the
semi-infinite chain of points.Comment: 14 pages, 2 figure
On the Yang-Lee and Langer singularities in the O(n) loop model
We use the method of `coupling to 2d QG' to study the analytic properties of
the universal specific free energy of the O(n) loop model in complex magnetic
field. We compute the specific free energy on a dynamical lattice using the
correspondence with a matrix model. The free energy has a pair of Yang-Lee
edges on the high-temperature sheet and a Langer type branch cut on the
low-temperature sheet. Our result confirms a conjecture by A. and Al.
Zamolodchikov about the decay rate of the metastable vacuum in presence of
Liouville gravity and gives strong evidence about the existence of a weakly
metastable state and a Langer branch cut in the O(n) loop model on a flat
lattice. Our results are compatible with the Fonseca-Zamolodchikov conjecture
that the Yang-Lee edge appears as the nearest singularity under the Langer cut.Comment: 38 pages, 16 figure
A Gas Giant Circumbinary Planet Transiting the F Star Primary of the Eclipsing Binary Star KIC 4862625 and the Independent Discovery and Characterization of the two transiting planets in the Kepler-47 System
We report the discovery of a transiting, gas giant circumbinary planet
orbiting the eclipsing binary KIC 4862625 and describe our independent
discovery of the two transiting planets orbiting Kepler-47 (Orosz et al. 2012).
We describe a simple and semi-automated procedure for identifying individual
transits in light curves and present our follow-up measurements of the two
circumbinary systems. For the KIC 4862625 system, the 0.52+/-0.018 RJup radius
planet revolves every ~138 days and occults the 1.47+/-0.08 MSun, 1.7 +/-0.06
RSun F8 IV primary star producing aperiodic transits of variable durations
commensurate with the configuration of the eclipsing binary star. Our best-fit
model indicates the orbit has a semi-major axis of 0.64 AU and is slightly
eccentric, e=0.1. For the Kepler-47 system, we confirm the results of Orosz et
al. (2012). Modulations in the radial velocity of KIC 4862625A are measured
both spectroscopically and photometrically, i.e. via Doppler boosting, and
produce similar results.Comment: 40 pages, 17 figure
Система автоматического закрывания окон
Объектом исследования является система, предназначенная обеспечить безопасность эксплуатации оконных систем, в квартирах с детьми.
Цель работы – разработать систему автоматического закрывания окон, обеспечивающую максимальную безопасность, тем самым снизить количество несчастных случаев и уровня смертности среди детей, связанного с падениями из окон.The object of study is a system designed to ensure the safe operation of window systems, in apartments with children.
The aim of this work is to develop a system for automatic closing of Windows for maximum safety, thereby reducing the number of accidents and mortality among children associated with falls from Windows
Paradoxical suboptimal vitamin D levels in a Mediterranean area: a population-based study
Policies in sunny countries, such as those in the Mediterranean area, do not promote vitamin D supplementation despite some studies might suggest the high prevalence of sub-optimal levels. The objective was to determine the vitamin D levels by 25-hydroxyvitamin D (25(OH)D) of a Mediterranean population and their characteristics. This population-based study included a database of public health system from all individuals living in Catalonia > 18 years who had some measure of 25(OH)D between January 2018 and April 2021. More than half million people were classified based on 25(OH)D measurements to study their characteristics. Three vitamin D categories were created: 30 ng/ml optimal. Less than 10% of the population residing in Catalonia had recent 25(OH)D determinations and the majority of determinations were in >= 45 years and in women. Around 80% of young people with determination had sub-optimal levels but the prevalence of vitamin D supplementation prescription increased with age which was associated with better values of 25(OH)D. In a Mediterranean area 25(OH)D determinations were low despite the high prevalence of suboptimal levels in the population with recent determination. In addition, the measurements were especially concentrated in people >= 45 years of age and in women who were, in addition, the groups to whom the most vitamin D supplementation was prescribed. On the contrary, young people presented few determinations of 25(OH)D and, although majority of them showed sub-optimal levels, vitamin D supplementation was not prescribed in most cases
Loop Equations for + and - Loops in c = 1/2 Non-Critical String Theory
New loop equations for all genera in non-critical string
theory are constructed. Our loop equations include two types of loops, loops
with all Ising spins up (+ loops) and those with all spins down ( loops).
The loop equations generate an algebra which is a certain extension of
algebra and are equivalent to the constraints derived before in the
matrix-model formulation of 2d gravity. Application of these loop equations to
construction of Hamiltonian for string field theory is
considered.Comment: 21 pages, LaTex file, no figure
Topological expansion of the 2-matrix model correlation functions: diagrammatic rules for a residue formula
We solve the loop equations of the hermitian 2-matrix model to all orders in
the topological expansion, i.e. we obtain all non-mixed correlation
functions, in terms of residues on an algebraic curve. We give two
representations of those residues as Feynman-like graphs, one of them involving
only cubic vertices.Comment: 48 pages, LaTex, 68 figure
Loop models, random matrices and planar algebras
We define matrix models that converge to the generating functions of a wide
variety of loop models with fugacity taken in sets with an accumulation point.
The latter can also be seen as moments of a non-commutative law on a subfactor
planar algebra. We apply this construction to compute the generating functions
of the Potts model on a random planar map
Risk Prescriptions of Strong Opioids in the Treatment of Chronic Non-Cancer Pain by Primary Care Physicians in Catalonia: Opicat Padris Project
The prescription of strong opioids (SO) for chronic non-cancer pain (CNCP) is steadily increasing. This entails a high risk of adverse effects, a risk that increases with the concomitant prescription of SO with central nervous system depressant drugs and with the use of SO for non-recommended indications. In order to examine this concomitant risk prescription, we designed a descriptive, longitudinal, retrospective population-based study. Patients aged >= 15 years with a continued SO prescription for >= 3 months during 2013-2017 for CNCP were included. Of these, patients who had received concomitant prescriptions of SO and risk drugs (gabapentinoids, benzodiazepines and antidepressants) and those who had received immediate-release fentanyl (IRF) were selected. The study included 22,691 patients; 20,354 (89.7%) patients received concomitant risk prescriptions. Men and subjects with a higher socioeconomic status received fewer concomitant risk prescriptions. Benzodiazepines or Z-drugs were prescribed concomitantly with SO in 15,883 (70%) patients, antidepressants in 14,932 (65%) and gabapentinoids in 11,267 (49%), while 483 (21.32%) patients received IRF (2266 prescriptions in total) without a baseline SO. In conclusion, our study shows that a high percentage of patients prescribed SO for CNCP received concomitant prescriptions with known risks, as well as IRF for unauthorized indications
Trends in the Prescription of Strong Opioids for Chronic Non-Cancer Pain in Primary Care in Catalonia: Opicat-Padris-Project
In chronic non-cancer pain (CNCP), evidence of the effectiveness of strong opioids (SO) is very limited. Despite this, their use is increasingly common. To examine SO prescriptions, we designed a descriptive, longitudinal, retrospective population-based study, including patients aged >= 15 years prescribed SO for >= 3 months continuously in 2013-2017 for CNCP in primary care in Catalonia. Of the 22,691 patients included, 17,509 (77.2%) were women, 10,585 (46.6%) were aged >80 years, and most had incomes of <euro18,000 per year. The most common diagnoses were musculoskeletal diseases and psychiatric disorders. There was a predominance of transdermal fentanyl in the defined daily dose (DDD) per thousand inhabitants/day, with the greatest increase for tapentadol (312% increase). There was an increase of 66.89% in total DDD per thousand inhabitants/day for SO between 2013 (0.737) and 2017 (1.230). The mean daily oral morphine equivalent dose/day dispensed for all drugs was 83.09 mg. Transdermal fentanyl and immediate transmucosal release were the largest cost components. In conclusion, there was a sustained increase in the prescription of SO for CNCP, at high doses, and in mainly elderly patients, predominantly low-income women. The new SO are displacing other drugs
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