1,158 research outputs found
Exploring Hidden Atrial Fibrillation in Patients with Type 2 Diabetes Mellitus Admitted to Shinshu University Hospital
Using the event-triggered recorder, SpiderFlash-t AFIB, which allows us to detect asymptomatic or symptomatic arrhythmia, we examined the prevalence of hidden atrial fibrillation (AF) in patients with type 2 diabetes admitted to our hospital. In total, we enrolled 69 patients with type 2 diabetes mellitus admitted to the hospital due to hyperglycemia. Averages of HbA1c, age, duration of the disease, and BMI were 8.9 %, 64.8 years old, 14.8 years, and 26.0 kg/m2, respectively. Neuropathy, retinopathy, and nephropathy were found in 37 (53.6 %), 27 (39.1 %), and 27 (39.1 %), respectively. Macroangiopathy was found in 13 (18.9 %). In the first series of surveys where we attached the recorder for 7 days no sustained AF events were found, and only 2 transient events. We attached the recorder for 14 days with 39 subjects in the second series of the survey, and fail to find any AF rhythm. This study is the first attempt to reveal the frequency of hidden AF in diabetes. This finding suggests that screening of atrial fibrillation with SpiderFlash-t AFIB for patients with type 2 diabetic patients hospitalized for glycemic control may not be useful in assessing the prevalence of atrial fibrillation.Article信州医学雑誌 69(2): 75-81(2021)departmental bulletin pape
Agent-based simulation of a financial market
This paper introduces an agent-based artificial financial market in which
heterogeneous agents trade one single asset through a realistic trading
mechanism for price formation. Agents are initially endowed with a finite
amount of cash and a given finite portfolio of assets. There is no
money-creation process; the total available cash is conserved in time. In each
period, agents make random buy and sell decisions that are constrained by
available resources, subject to clustering, and dependent on the volatility of
previous periods. The model herein proposed is able to reproduce the
leptokurtic shape of the probability density of log price returns and the
clustering of volatility. Implemented using extreme programming and
object-oriented technology, the simulator is a flexible computational
experimental facility that can find applications in both academic and
industrial research projects.Comment: 11 pages, 3 EPS figures, LaTEX. To be published in Physica A
(Proceedings of the NATO Advanced Research Workshop on Application of Physics
in Economic Modelling, Prague 8-10 February 2001
Simulations on the Effect of Magnetic Anisotropy on Switching of an Easy Cone Magnetized Free Layer
The easy cone state of magnetization that arises as a result of a competition between the second- and fourth-order perpendicular magnetic anisotropies has the advantage of a non-zero electric-field torque without the application of a bias magnetic field and is thus a potential candidate for purely voltage-driven magnetic storage devices. In this article, the onset of the easy cone state of magnetization is simulated in a ferromagnet film. Subsequently, the switching field and time for voltage-controlled magnetization switching process are studied as a function of the inclination angle of the easy cone state from the film normal in the range of 0°- 45°. The switching field is found to decrease with decreasing anisotropy. The switching time is found to become faster for higher inclination angle of the easy cone state due to an increase in its torque
Volatility Cluster and Herding
Stock markets can be characterized by fat tails in the volatility
distribution, clustering of volatilities and slow decay of their time
correlations. For an explanation models with several mechanisms and
consequently many parameters as the Lux-Marchesi model have been used. We show
that a simple herding model with only four parameters leads to a quantitative
description of the data. As a new type of data we describe the volatility
cluster by the waiting time distribution, which can be used successfully to
distinguish between different models.Comment: 15 pages TeX, 6 figures PostScrip
Evolution of the nitric oxide synthase family in vertebrates and novel insights in gill development
Nitric oxide (NO) is an ancestral key signalling molecule essential for life and has enormous versatility in biological systems, including cardiovascular homeostasis, neurotransmission and immunity. Although our knowledge of NO synthases (Nos), the enzymes that synthesize NO in vivo, is substantial, the origin of a large and diversified repertoire of nos gene orthologues in fishes with respect to tetrapods remains a puzzle. The recent identification of nos3 in the ray-finned fish spotted gar, which was considered lost in this lineage, changed this perspective. This finding prompted us to explore nos gene evolution, surveying vertebrate species representing key evolutionary nodes. This study provides noteworthy findings: first, nos2 experienced several lineage-specific gene duplications and losses. Second, nos3 was found to be lost independently in two different teleost lineages, Elopomorpha and Clupeocephala. Third, the expression of at least one nos paralogue in the gills of developing shark, bichir, sturgeon, and gar, but not in lamprey, suggests that nos expression in this organ may have arisen in the last common ancestor of gnathostomes. These results provide a framework for continuing research on nos genes’ roles, highlighting subfunctionalization and reciprocal loss of function that occurred in different lineages during vertebrate genome duplications
Volatility clustering and scaling for financial time series due to attractor bubbling
A microscopic model of financial markets is considered, consisting of many
interacting agents (spins) with global coupling and discrete-time thermal bath
dynamics, similar to random Ising systems. The interactions between agents
change randomly in time. In the thermodynamic limit the obtained time series of
price returns show chaotic bursts resulting from the emergence of attractor
bubbling or on-off intermittency, resembling the empirical financial time
series with volatility clustering. For a proper choice of the model parameters
the probability distributions of returns exhibit power-law tails with scaling
exponents close to the empirical ones.Comment: For related publications see http://www.helbing.or
Observation of Exclusive Gamma Gamma Production in p pbar Collisions at sqrt{s}=1.96 TeV
We have observed exclusive \gamma\gamma production in proton-antiproton
collisions at \sqrt{s}=1.96 TeV, using data from 1.11 \pm 0.07 fb^{-1}
integrated luminosity taken by the Run II Collider Detector at Fermilab. We
selected events with two electromagnetic showers, each with transverse energy
E_T > 2.5 GeV and pseudorapidity |\eta| < 1.0, with no other particles detected
in -7.4 < \eta < +7.4. The two showers have similar E_T and azimuthal angle
separation \Delta\phi \sim \pi; 34 events have two charged particle tracks,
consistent with the QED process p \bar{p} to p + e^+e^- + \bar{p} by two-photon
exchange, while 43 events have no charged tracks. The number of these events
that are exclusive \pi^0\pi^0 is consistent with zero and is < 15 at 95% C.L.
The cross section for p\bar{p} to p+\gamma\gamma+\bar{p} with |\eta(\gamma)| <
1.0 and E_T(\gamma) > 2.5$ GeV is
2.48^{+0.40}_{-0.35}(stat)^{+0.40}_{-0.51}(syst) pb.Comment: 7 pages, 4 figure
Combined search for the standard model Higgs boson decaying to a bb pair using the full CDF data set
We combine the results of searches for the standard model Higgs boson based
on the full CDF Run II data set obtained from sqrt(s) = 1.96 TeV p-pbar
collisions at the Fermilab Tevatron corresponding to an integrated luminosity
of 9.45/fb. The searches are conducted for Higgs bosons that are produced in
association with a W or Z boson, have masses in the range 90-150 GeV/c^2, and
decay into bb pairs. An excess of data is present that is inconsistent with the
background prediction at the level of 2.5 standard deviations (the most
significant local excess is 2.7 standard deviations).Comment: To be published in Phys. Rev. Lett (v2 contains minor updates based
on comments from PRL
A search for resonant production of pairs in $4.8\ \rm{fb}^{-1}p\bar{p}\sqrt{s}=1.96\ \rm{TeV}$
We search for resonant production of tt pairs in 4.8 fb^{-1} integrated
luminosity of ppbar collision data at sqrt{s}=1.96 TeV in the lepton+jets decay
channel, where one top quark decays leptonically and the other hadronically. A
matrix element reconstruction technique is used; for each event a probability
density function (pdf) of the ttbar candidate invariant mass is sampled. These
pdfs are used to construct a likelihood function, whereby the cross section for
resonant ttbar production is estimated, given a hypothetical resonance mass and
width. The data indicate no evidence of resonant production of ttbar pairs. A
benchmark model of leptophobic Z \rightarrow ttbar is excluded with m_{Z'} <
900 GeV at 95% confidence level.Comment: accepted for publication in Physical Review D Sep 21, 201
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