484 research outputs found
Long Waves in World Industrial Production, Energy Consumption, Innovations, Inventions, and Patents and their Identification by Spectral Analysis
Scientists like to make the irregular regular, to draw curves even in cases where nothing can be seen at all. Periodical wave curves are an excellent means of organizing the unorganized, of arranging the unarranged. Recent studies on long waves in economic development have found a periodicity in the time series of inventions and innovations that works exactly like a clock with an accelerating mechanism. What we have done here is simply to collect some interesting empirical figures and to exploit them by spectral analysis in order to find out whether regularities exist, and if so, whether they are statistically significant
Thin presentation of knots and lens spaces
This paper concerns thin presentations of knots K in closed 3-manifolds M^3
which produce S^3 by Dehn surgery, for some slope gamma. If M does not have a
lens space as a connected summand, we first prove that all such thin
presentations, with respect to any spine of M have only local maxima. If M is a
lens space and K has an essential thin presentation with respect to a given
standard spine (of lens space M) with only local maxima, then we show that K is
a 0-bridge or 1-bridge braid in M; furthermore, we prove the minimal
intersection between K and such spines to be at least three, and finally, if
the core of the surgery K_gamma yields S^3 by r-Dehn surgery, then we prove the
following inequality: |r| <= 2g, where g is the genus of K_gamma.Comment: Published by Algebraic and Geometric Topology at
http://www.maths.warwick.ac.uk/agt/AGTVol3/agt-3-23.abs.htm
The maximum modulus of a trigonometric trinomial
Let Lambda be a set of three integers and let C_Lambda be the space of
2pi-periodic functions with spectrum in Lambda endowed with the maximum modulus
norm. We isolate the maximum modulus points x of trigonometric trinomials T in
C_Lambda and prove that x is unique unless |T| has an axis of symmetry. This
permits to compute the exposed and the extreme points of the unit ball of
C_Lambda, to describe how the maximum modulus of T varies with respect to the
arguments of its Fourier coefficients and to compute the norm of unimodular
relative Fourier multipliers on C_Lambda. We obtain in particular the Sidon
constant of Lambda
Rural Children Experience Different Rates of Mental Health Diagnosis and Treatment
Research indicates that privately insured, rural adults have lower use of office-based mental health services, but higher use of prescription medicines than their urban counterparts. Patterns for rural children may be different from urban children because of the limited supply of pediatric mental health providers in rural areas, which may lead to reduced access and lower use of mental health services in rural areas versus urban. Using data on children ages 5-17 from the 2002-2008 of the Medical Expenditure Panel Survey, researchers from the Maine Rural Health Research Center find that rural children are significantly less likely to be diagnosed and treated for non-ADHD mental health problems than urban children and are less likely to receive mental health counseling. The rural-urban difference is greatest among those children scoring in the “possible impairment” range on the Columbia Impairment Scale
Patterns of Care for Rural and Urban Children with Mental Health Problems
Introduction
Research indicates that privately insured, rural adults have lower use of office-based mental health services, but higher use of prescription medicines than their urban counterparts. Similar studies for rural children have been limited to specific populations, diagnoses, or to single states. Patterns for rural children may be different than those of urban children and adults generally because of their high enrollment in Medicaid and the State Children\u27s Health Insurance Program, which tend to have more generous behavioral health benefits than private coverage and may equalize rural-urban treatment patterns. On the other hand, the more limited supply of specialty mental health providers in rural areas, particularly for children, could lead to lack of access and lower utilization of some types of mental health services in rural areas versus urban.
Methods
Using data on children ages 5-17 from the 2002-2008 Medical Expenditure Panel Survey, this study examines two research questions: 1) do patterns of children\u27s mental health diagnosis and service use (e.g., office visits and psychotropic medications) differ by rural-urban residence? and 2) what is the effect of income and insurance type on use of mental health services?
Findings
Controlling for demographic and risk factors, rural children are as likely as urban children to have an attention deficit or hyperactivity disorder (ADHD) diagnosis and less likely to have any other type of psychiatric diagnosis. Initially observed higher prevalence of mental health diagnoses among rural children is explained by underlying differences in demographic characteristics and risk factors, such as higher rates of poverty, public coverage, mental health impairment, and lower prevalence of minorities. Rural children with the highest mental health need are no more or less likely to be diagnosed or treated for mental health conditions. However, among those with a possible impairment, rural children are less likely to be diagnosed with a psychiatric illness other than ADHD and are less likely to receive counseling
Quality Control of Motor Unit Number Index (MUNIX) Measurements in 6 Muscles in a Single-Subject “Round-Robin” Setup
Background
Motor Unit Number Index (MUNIX) is a neurophysiological measure that provides an index
of the number of lower motor neurons in a muscle. Its performance across centres in healthy
subjects and patients with Amyotrophic Lateral Sclerosis (ALS) has been established, but
inter-rater variability between multiple raters in one single subject has not been
investigated.
Objective
To assess reliability in a set of 6 muscles in a single subject among 12 examiners (6 experienced
with MUNIX, 6 less experienced) and to determine variables associated with variability
of measurements.
Methods
Twelve raters applied MUNIX in six different muscles (abductor pollicis brevis (APB),
abductor digiti minimi (ADM), biceps brachii (BB), tibialis anterior (TA), extensor dig. brevis
(EDB), abductor hallucis (AH)) twice in one single volunteer on consecutive days. All raters
visited at least one training course prior to measurements. Intra- and inter-rater variability as
determined by the coefficient of variation (COV) between different raters and their levels of
experience with MUNIX were compared.
Results
Mean intra-rater COV of MUNIX was 14.0% (±6.4) ranging from 5.8 (APB) to 30.3% (EDB).
Mean inter-rater COV was 18.1 (±5.4) ranging from 8.0 (BB) to 31.7 (AH). No significant differences
of variability between experienced and less experienced raters were detected.
Conclusion
We provide evidence that quality control for neurophysiological methods can be performed
with similar standards as in laboratory medicine. Intra- and inter-rater variability of MUNIX is
muscle-dependent and mainly below 20%. Experienced neurophysiologists can easily
adopt MUNIX and adequate teaching ensures reliable utilization of this method
Return to driving after traumatic brain injury : a British perspective
Primary Objective: to identify current legal situation, and professional practice in assisting persons with traumatic brain injury (TBI) to return to safe driving after injury.
Methods and Procedures
A brief review of relevant literature, a description of the current statutory and quasi-statutory authorities regulating return to driving after TBI in the UK, and a description of the nature and resolution of clinical and practical dilemmas facing professionals helping return to safe driving after TBI. Each of the 15 UK mobility centres was contacted and literature requested; in addition a representative of each centre responded to a structured telephone survey.
Main Outcome and Results: The current situation in Great Britain is described, with a brief analysis of the strengths and weaknesses both of the current statutory situation, and also the practical situation (driving centres), with suggestions for improvements in practice.
Conclusion
Although brain injury may cause serious limitations in driving ability, previous drivers are not routinely assessed or advised regarding return to driving after TBI
Noncommutative Figa-Talamanca-Herz algebras for Schur multipliers
We introduce a noncommutative analogue of the Fig\'a-Talamanca-Herz algebra
on the natural predual of the operator space of
completely bounded Schur multipliers on Schatten space . We determine the
isometric Schur multipliers and prove that the space of bounded
Schur multipliers on Schatten space is the closure in the weak operator
topology of the span of isometric multipliers.Comment: 24 pages; corrected typo
Evaluation of real-life outcome data of patients with spinal muscular atrophy treated with nusinersen in Switzerland.
Spinal muscular atrophy (SMA) is an autosomal recessive disorder causing progressive proximal muscular, respiratory, and bulbar weakness. We present outcome data on motor function, ventilation, nutrition, and language development of SMA patients treated with nusinersen in Switzerland. This multicenter, observational study included 44 patients. At treatment initiation, after 2 months and then every 4 months we assessed motor function with the Children's Hospital of Philadelphia Infant Test of Neuromuscular Disorders (CHOP-INTEND), Hammersmith Functional Motor Scale expanded (HFMSE) and 6-Minute Walk Test (6MWT). At treatment initiation, patients were 0.1-44.6 years old, treatment duration ranged from 6 to 41 months. All 11 SMA type 1 children achieved higher CHOP-INTEND scores at the last assessment compared to treatment initiation, 4 acquired stable sitting. Six type 1 children were <18 months-old at treatment initiation. Two of them did not need ventilation or nutritional support at the last assessment; three had delayed language development and 3 articulation difficulties. 5/21 SMA type 2 patients achieved higher HFMSE scores. All ambulant type 3 patients showed a gain in the 6MWT. Nusinersen is an effective treatment, with gains in motor function occurring particularly in children and SMA type 1, but also in type 2 and 3, adolescents and adults
Quantum key distribution with entangled photons generated on demand by a quantum dot
Quantum key distribution-exchanging a random secret key relying on a quantum mechanical resource-is the core feature of secure quantum networks. Entanglement-based protocols offer additional layers of security and scale favorably with quantum repeaters, but the stringent requirements set on the photon source have made their use situational so far. Semiconductor-based quantum emitters are a promising solution in this scenario, ensuring on-demand generation of near-unity-fidelity entangled photons with record-low multiphoton emission, the latter feature countering some of the best eavesdropping attacks. Here, we use a coherently driven quantum dot to experimentally demonstrate a modified Ekert quantum key distribution protocol with two quantum channel approaches: both a 250-m-long single-mode fiber and in free space, connecting two buildings within the campus of Sapienza University in Rome. Our field study highlights that quantum-dot entangled photon sources are ready to go beyond laboratory experiments, thus opening the way to real-life quantum communication
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