103 research outputs found
Canonical equilibrium distribution derived from Helmholtz potential
Plastino and Curado [Phys. Rev. E 72, 047103 (2005)] recently determined the
equilibrium probability distribution for the canonical ensemble using only
phenomenological thermodynamical laws as an alternative to the entropy
maximization procedure of Jaynes. In the current paper we present another
alternative derivation of the canonical equilibrium probability distribution,
which is based on the definition of the Helmholtz free energy (and its being
constant at the equilibrium) and the assumption of the uniqueness of the
equilibrium probability distribution. Noting that this particular derivation is
applicable for all trace-form entropies, we also apply it to the Tsallis
entropy showing that the Tsallis entropy yields genuine inverse power laws.Comment: 7 pages. Accepted for publication in Physica
The use of Amplatzer Vascular Plug® to treat coronary steal due to unligated thoracic side branch of left internal mammary artery: Four year follow-up results
Left internal mammary artery (LIMA) is the most commonly used graft during coronary
bypass surgery. LIMA side branches are clipped during surgery in order to prevent coronary
steal. In cases of patent LIMA side branches, there are differingapproaches. Herein, we report
a case with patent thoracic side branch of LIMA graft, occlusion of this side branch by
Amplatzer Vascular Plug because of documented myocardial ischemia, and long term
follow-up results. (Cardiol J 2012; 19, 2: 197–200
Self-organization in dissipative optical lattices
We show that the transition from Gaussian to the q-Gaussian distributions
occurring in atomic transport in dissipative optical lattices can be
interpreted as self-organization by recourse to a modified version of
Klimontovich's S-theorem. As a result, we find that self-organization is
possible in the transition regime, only where the second moment is
finite. Therefore, the nonadditivity parameter q is confined within the range
1<q<5/3, although whole spectrum of q values i.e., 1<q<3, is considered
theoretically possible. The range of q values obtained from the modified
S-theorem is also confirmed by the experiments carried out by Douglas et al.
[Phys. Rev. Lett. 96, 110601 (2006)].Comment: 9 pages, 1 fi
On the way towards a generalized entropy maximization procedure
We propose a generalized entropy maximization procedure, which takes into
account the generalized averaging procedures and information gain definitions
underlying the generalized entropies. This novel generalized procedure is then
applied to Renyi and Tsallis entropies. The generalized entropy maximization
procedure for Renyi entropies results in the exponential stationary
distribution asymptotically for q is between [0,1] in contrast to the
stationary distribution of the inverse power law obtained through the ordinary
entropy maximization procedure. Another result of the generalized entropy
maximization procedure is that one can naturally obtain all the possible
stationary distributions associated with the Tsallis entropies by employing
either ordinary or q-generalized Fourier transforms in the averaging procedure.Comment: 12 pages, no figure
Evaluation of atrial electromechanical conduction delay in case of hemodynamically insignificant rheumatic heart disease: A tissue Doppler study
Background: Atrial electromechanical delay (AEMD) that reflects delayed conduction may show us the clinical reflection of pathological changes in the atria. The main objective of the present study is to investigate AEMD in patients who had previous rheumatic carditis but without hemodynamically significant valvular disease.
Methods: A total of 40 patients, previously diagnosed as rheumatic carditis but without significant valvular stenosis/regurgitation and atrial enlargement; and 39 age- and-sex matched controls were enrolled for the present study. Parameters of AEMD (lateral mitral annulus electromechanical delay, septal mitral annulus electromechanical delay and lateral tricuspid annulus electromechanical delay) were measured with tissue Doppler echocardiography and left intra-atrial and inter-atrial conduction times were calculated accordingly. A 24h ambulatory Holter monitoring was used in both groups to detect atrial fibrillation episodes and quantify atrial extrasystoles.
Results: Parameters of AEMD, including left intra-atrial and inter-atrial conduction times of subjects in the study group were longer compared to the control group (23.7 ± 7.0 vs. 18.3 ± 6.2).
Conclusions: Increased AEMD is observed in patients with previous rheumatic carditis and no significant valvular stenosis/regurgitation and atrial enlargement, which may partly explain the increased incidence of atrial fibrillation observed in these patients
Total white blood cell count is associated with the presence, severity and extent of coronary atherosclerosis detected by dual-source multislice computed tomographic coronary angiography
Background: Total white blood cell (WBC) count has been consistently shown to be an
independent risk factor and predictor for future cardiovascular outcomes, regardless of disease
status in coronary artery disease (CAD). The purpose of this study is to evaluate the relationship
between total WBC count and the presence, severity and extent of coronary atherosclerosis
detected in subjects undergoing multislice computed tomographic (MSCT) coronary angiography
for suspected CAD.
Methods: A total of 817 patients were enrolled in this cross-sectional study. Non-significant
coronary plaque was defined as lesions causing £ 50% luminal narrowing, and significant
coronary plaque was defined as lesions causing > 50% luminal narrowing. For each segment,
coronary atherosclerotic lesions were categorized as none, calcified, non-calcified and mixed.
All images were interpreted immediately after scanning by an experienced radiologist.
Results: An association between hypertension, diabetes mellitus, age, gender, hyperlipidemia,
smoking, total WBC counts and coronary atherosclerosis was found when patients were
grouped into two categories according to the presence of coronary atherosclerosis (p < 0.05).
Although plaque morphology was not associated with total WBC counts, the extent of coronary
atherosclerosis was increased with higher total WBC quartiles (p = 0.006). Patients with
critical luminal stenosis had higher levels of total WBC counts when compared to patients with
non-critical luminal narrowing (7,982 ± 2,287 vs 7,184 ± 1,944, p < 0.05).
Conclusions: Our study demonstrated that total WBC counts play an important role in
inflammation and are associated with the presence, severity and extent of coronary atherosclerosis
detected by MSCT. Further studies are needed to assess the true impact of WBC counts
on coronary atherosclerosis, and to promote its use in predicting CAD. (Cardiol J 2011; 18, 4:
371–377
Renal complications of lipodystrophy: A closer look at the natural history of kidney disease
Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/144612/1/cen13732_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/144612/2/cen13732.pd
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