74 research outputs found
NJL Model at Finite Chemical Potential in a Constant Magnetic Field
We investigate the influence of an external magnetic field on chiral symmetry
breaking in the Nambu-Jona-Lasinio (NJL) model at finite temperature and
chemical potential. According to the Fock-Schwinger proper-time method, we
calculate the effective potential in the leading order of the
expansion. The phase boundary dividing the symmetric phase and the broken phase
is illustrated numerically. A complex behavior of the phase boundary is found
for large chemical potential.Comment: 6 pages, 2 figures, Poster talk presented at the Workshop on Finite
Density QCD at Nara, Japan, 10-12 July 2003; replaced two reference
Four-fermion Interaction Model in a Constant Magnetic Field at Finite Temperature and Chemical Potential
We investigate an influence of an external magnetic field on chiral symmetry
breaking in a four-fermion interaction model at finite temperature and chemical
potential. By using the Fock-Schwinger proper-time method, we calculate the
effective potential for the four-fermion interaction model at the leading order
of the expansion. A phase structure of the chiral symmetry breaking is
shown on -, - and - planes. The external magnetic field
modifies the phase structure. It is found that a new phase appears for a large
chemical potential.Comment: 16 pages, 10 figure
Feasibility of Probing Dark Energy with Strong Gravitational Lensing Systems -- Fisher-Matrix Approach --
We assess the feasibility of probing dark energy with strong gravitational
lensing systems. The capability of the method, which depends on the accuracy
with which the lensing systems are modeled, is quantitatively investigated
using the Fisher-matrix formalism. We show that this method might place useful
constraints on the density parameter and the redshift evolution of the dark
energy by combining it with a constraint from supernova measurements. For this
purpose, the lens potential needs to be precisely reconstructed. We determine
the required quality of data. We also briefly discuss the optimal strategy to
constrain the cosmological parameters using gravitational lensing systems.Comment: 14 pages, 6 figures. Progress of Theoretical Physics, Vol 106, in
pres
Periodic alternation between intake and exhaust of air in dynamic insulation
Dynamic insulation (DI) can recover heat lost in conduction by drawing cold outdoor air into indoor through an insulation wall in winter. A âbreathing DIâ system we proposed in the past has functions both as an insulated envelope and as a highly efficient heat exchanger for ventilation. It is alternated periodically that the outdoor air is drawn through half of walls made of breathable inorganic concrete (BIC) and the indoor air is exhausted through the other half of the BIC walls. In order to put the breathing DI system into practice in housing construction, this paper presents some studies from various points of view in addition to the past studies on heat and moisture transport based on laboratory experiments and numerical simulations. We first experimentally studied the filtering efficiency and clogging of a BIC panel. This showed that approximately 30 % of the atmospheric dust can be captured by a BIC panel and no clogging would occur for at least 10 years. We also measured the sorption and desorption of formaldehyde by a BIC panel to confirm the effectiveness of a BIC wall to sorb gaseous state formaldehyde. We furthermore constructed a new test house at Ibaraki, Japan, to confirm the thermal performance of the breathing DI system based on full scale experiments
Decline in Left Ventricular Ejection Fraction during Follow-up in Patients with Severe Aortic Stenosis
Objectives: The aim of this study was to investigate the prognostic impact of the decline in left ventricular ejection fraction (LVEF) at 1-year follow-up in patients with severe aortic stenosis (AS) managed conservatively. Background: No previous study has explored the association between LVEF decline during follow-up and clinical outcomes in patients with severe AS. Methods: Among 3, 815 patients with severe AS enrolled in the multicenter CURRENT AS (Contemporary Outcomes After Surgery and Medical Treatment in Patients With Severe Aortic Stenosis) registry in Japan, 839 conservatively managed patients who underwent echocardiography at 1-year follow-up were analyzed. The primary outcome measure was a composite of AS-related deaths and hospitalization for heart failure. Results: There were 91 patients (10.8%) with >10% declines in LVEF and 748 patients (89.2%) without declines. Left ventricular dimensions and the prevalence of valve regurgitation and atrial fibrillation or flutter significantly increased in the group with declines in LVEF. The cumulative 3-year incidence of the primary outcome measure was significantly higher in the group with declines in LVEF than in the group with no decline (39.5% vs. 26.5%; p 10% declines in LVEF at 1 year after diagnosis had worse AS-related clinical outcomes than those without declines in LVEF under conservative management. (Contemporary Outcomes After Surgery and Medical Treatment in Patients With Severe Aortic Stenosis Registry; UMIN000012140
Initial Surgical Versus Conservative Strategies in Patients With Asymptomatic Severe Aortic Stenosis
AbstractBackgroundCurrent guidelines generally recommend watchful waiting until symptoms emerge for aortic valve replacement (AVR) in asymptomatic patients with severe aortic stenosis (AS).ObjectivesThe study sought to compare the long-term outcomes of initial AVR versus conservative strategies following the diagnosis of asymptomatic severe AS.MethodsWe used data from a large multicenter registry enrolling 3,815 consecutive patients with severe AS (peak aortic jet velocity >4.0 m/s, or mean aortic pressure gradient >40 mm Hg, or aortic valve area <1.0 cm2) between January 2003 and December 2011. Among 1,808 asymptomatic patients, the initial AVR and conservative strategies were chosen in 291 patients, and 1,517 patients, respectively. Median follow-up was 1,361 days with 90% follow-up rate at 2 years. The propensity scoreâmatched cohort of 582 patients (n = 291 in each group) was developed as the main analysis set for the current report.ResultsBaseline characteristics of the propensity scoreâmatched cohort were largely comparable, except for the slightly younger age and the greater AS severity in the initial AVR group. In the conservative group, AVR was performed in 41% of patients during follow-up. The cumulative 5-year incidences of all-cause death and heart failure hospitalization were significantly lower in the initial AVR group than in the conservative group (15.4% vs. 26.4%, p = 0.009; 3.8% vs. 19.9%, p < 0.001, respectively).ConclusionsThe long-term outcome of asymptomatic patients with severe AS was dismal when managed conservatively in this real-world analysis and might be substantially improved by an initial AVR strategy. (Contemporary Outcomes After Surgery and Medical Treatment in Patients With Severe Aortic Stenosis Registry; UMIN000012140
Functional annotation of human long noncoding RNAs via molecular phenotyping
Long noncoding RNAs (lncRNAs) constitute the majority of transcripts in the mammalian genomes, and yet, their functions remain largely unknown. As part of the FANTOM6 project, we systematically knocked down the expression of 285 lncRNAs in human dermal fibroblasts and quantified cellular growth, morphological changes, and transcriptomic responses using Capped Analysis of Gene Expression (CAGE). Antisense oligonucleotides targeting the same lncRNAs exhibited global concordance, and the molecular phenotype, measured by CAGE, recapitulated the observed cellular phenotypes while providing additional insights on the affected genes and pathways. Here, we disseminate the largest-todate lncRNA knockdown data set with molecular phenotyping (over 1000 CAGE deep-sequencing libraries) for further exploration and highlight functional roles for ZNF213-AS1 and lnc-KHDC3L-2.Peer reviewe
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