Determination of Pericardial Adipose Tissue Increases the Prognostic Accuracy of Coronary Artery Calcification for Future Cardiovascular Events

Objectives: Pericardial adipose tissue (PAT) is associated with coronary artery plaque accumulation and the incidence of coronary heart disease. We evaluated the possible incremental prognostic value of PAT for future cardiovascular events. Methods: 145 patients (94 males, age 60 10 years) with stable coronary artery disease underwent coronary artery calcification (CAC) scanning in a multislice CT scanner, and the volume of pericardial fat was measured. Mean observation time was 5.4 years. Results: 34 patients experienced a severe cardiac event. They had a significantly higher CAC score (1,708 +/- 2,269 vs. 538 +/- 1,150, p 400, 3.5 (1.9-5.4; p = 0.007) for scores > 800 and 5.9 (3.7-7.8; p = 0.005) for scores > 1,600. When additionally a PAT volume > 200 cm(3) was determined, there was a significant increase in the event rate and relative risk. We calculated a relative risk of 2.9 (1.9-4.2; p = 0.01) for scores > 400, 4.0 (2.1-5.0; p = 0.006) for scores > 800 and 7.1 (4.1-10.2; p = 0.005) for scores > 1,600. Conclusions:The additional determination of PAT increases the predictive power of CAC for future cardiovascular events. PAT might therefore be used as a further parameter for risk stratification. Copyright (C) 2012 S. Karger AG, Base

Determining the global minimum of Higgs potentials via Groebner bases - applied to the NMSSM

Determining the global minimum of Higgs potentials with several Higgs fields like the next-to-minimal supersymmetric extension of the Standard Model (NMSSM) is a non-trivial task already at the tree level. The global minimum of a Higgs potential can be found from the set of all its stationary points defined by a multivariate polynomial system of equations. We introduce here the algebraic Groebner basis approach to solve this system of equations. We apply the method to the NMSSM with CP conserving as well as CP violating parameters. The results reveal an interesting stationary-point structure of the potential. Requiring the global minimum to give the electroweak symmetry breaking observed in Nature excludes large parts of the parameter space.Comment: 10 pages, 2 figure

CT stress perfusion imaging for detection of haemodynamically relevant coronary stenosis as defined by FFR

Objectives: To evaluate the diagnostic accuracy (DA) of CT-myocardial perfusion imaging (CT-MPI) and a combined approach with CT angiography (CTA) for the detection of haemodynamically relevant coronary stenoses in patients with both suspected and known coronary artery disease. Design: Prospective, non-randomised, diagnostic study. Setting: Academic hospital-based study. Patients: 65 patients (42 men age 70.4 +/- 9) with typical or atypical chest pain. Interventions: CTA and CT-MPI with adenosine stress using a fast dual-source CT system. At subsequent invasive angiography, FFR measurement was performed in coronary arteries to define haemodynamic relevance of stenosis. Main outcome measures: We tried to correlate haemodynamically relevant stenosis (FFR <0.80) to a reduced myocardial blood flow (MBF) as assessed by CT-MPI and determined the DA of CT-MPI for the detection of haemodynamically relevant stenosis. Results: Sensitivity and negative predictive value (NPV) of CTA alone were very high (100% respectively) for ruling out haemodynamically significant stenoses, specificity, Positive predictive value (PPV) and DA were low (43.8, 67.3 and 72%, respectively). CT-MPI showed a significant increase in specificity, PPV and DA for the detection of haemodynamically relevant stenoses (65.6, 74.4 and 81.5%, respectively) with persisting high sensitivity and NPV for ruling out haemodynamically relevant stenoses (97% and 95.5% respectively). The combination of CTA and CT-MPI showed no further increase in detection of haemodynamically significant stenosis compared with CT-MPI alone. Conclusions: Our data suggest that CT-MPI permits the detection of haemodynamically relevant coronary artery stenoses with a moderate DA. CT may, therefore, allow the simultaneous assessment of both coronary morphology and function

Models of hydrothermal circulation within 106 Ma seafloor : constraints on the vigor of fluid circulation and crustal properties, below the Madeira Abyssal Plain

Author Posting. © American Geophysical Union, 2005. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Geochemistry Geophysics Geosystems 6 (2005): Q11001, doi:10.1029/2005GC001013.Heat flow measurements colocated with seismic data across 106 Ma seafloor of the Madeira Abyssal Plain (MAP) reveal variations in seafloor heat flow of ±10–20% that are positively correlated with basement relief buried below thick sediments. Conductive finite element models of sediments and upper basement using reasonable thermal properties are capable of generating the observed positive correlation between basement relief and seafloor heat flow, but with variability of just ±4–8%. Conductive simulations using a high Nusselt number (Nu) proxy for vigorous local convection suggest that Nu = 2–10 within the upper 600–100 m of basement, respectively, is sufficient to achieve a reasonable match to observations. These Nu values are much lower than those inferred on younger ridge flanks where greater thermal homogeneity is achieved in upper basement. Fully coupled simulations suggest that permeability below the MAP is on the order of 10−12–10−10 m2 within the upper 300–600 m of basement. This permeability range is broadly consistent with values determined by single-hole experiments and from modeling studies at other (mostly younger) sites. We infer that the reduction in basement permeability with age that is thought to occur within younger seafloor may slow considerably within older seafloor, helping hydrothermal convection to continue as plates age.Funding in support of this work was provided by the U.S. National Science Foundation (OCE-0001892), the U.S. Science Support Program for IODP (T301A7), and the Institute for Geophysics and Planetary Physics/Los Alamos National Laboratory (1317)

Al2O3-films on Ni3Al(111): a template for nanostructured cluster growth

In scanning tunnelling microscope images of thin Al2O3-films grown on Ni3Al(111) at 1000 K two super-lattices with periodicities of 2.6 and 4.5 nm, respectively, can be identified. These well-ordered nanostructures can be used as nucleation centres for metal particle growth. It can be shown that both nanostructures act as a template for the fabrication of ordered assemblies of metal clusters by mere physical vapour deposition. The degree of ordering of these nanostructures is largely dependent on the metal deposited. Here we report on the growth of Cu, Ag, Au, Mn, and V clusters on the Al2O3-films. The best results as far as ordering of the clusters is concerned was reached for V deposition at 550 K, which resulted in a nearly perfect hexagonal array of clusters with a spacing of 2.6 nm

Optically induced damping of the surface plasmon resonance in gold colloids

The surface plasmon damping induced by high excitation of the electron gas is studied in femtosecond pump-and-probe experiments on gold colloids embedded in a sol-gel matrix. Optical excitation of single-particle interband transitions leads to a pronounced broadening of the surface plasmon line. A similar behavior is observed for resonant excitation of the surface plasmon. This broadening is the dominant optical nonlinearity of the system, and reflects the excitation-induced damping of the surface plasmon resonance. The time evolution of the damping rate follows that of the electronic scattering rate

Cardiac arrest associated with sildenafil ingestion in a patient with an abnormal origin of the left coronary artery: case report

<p>Abstract</p> <p>Background</p> <p>Left coronary artery arising from the right sinus of Valsalva is an uncommon congenital coro-nary anomaly that seems to be associated with sudden death in young patients.</p> <p>Case presentation</p> <p>We report a case of cardiac arrest in a 59-year-old patient after sexual intercourse and Silde-nafil ingestion. A coronary arteriography and an angiographic computed tomography scan subsequently revealed a LCA origin from the right aortic sinus along with an intramural course of the left main stem. In addition a distal stenosis of the right coronary artery was detected. After successful resuscitation without neurological deficits coronary artery bypass surgery was performed.</p> <p>Conclusion</p> <p>To our knowledge, this is the first report demonstrating sudden cardiac arrest associated with Sildenafil ingestion in a patient with this type of coronary anomaly. The question arises, whether a cardiac screening is necessary before a Sildenafil therapy is initiated.</p

Radiative rotational lifetimes and state-resolved relative detachment cross sections from photodetachment thermometry of molecular anions in a cryogenic storage ring

Photodetachment thermometry on a beam of OH$^-$ in a cryogenic storage ring cooled to below 10 K is carried out using two-dimensional, frequency and time dependent photodetachment spectroscopy over 20 minutes of ion storage. In equilibrium with the low-level blackbody field, we find an effective radiative temperature near 15 K with about 90% of all ions in the rotational ground state. We measure the J = 1 natural lifetime (about 193 s) and determine the OH$^-$ rotational transition dipole moment with 1.5% uncertainty. We also measure rotationally dependent relative near-threshold photodetachment cross sections for photodetachment thermometry.Comment: Manuscript LaTeX with 5 pages, 3 figures, and 1 table plus LaTeX supplement with 12 pages, 3 figures and 3 tables. This article has been accepted by Physical Review Letter

Heat flow at the spreading centers of the Guaymas Basin, Gulf of California

Fifty-four new heat flow measurements in the central troughs of the Guaymas basin support the hypothesis that they are sites of active intrusion. In the northern trough a distinct pattern of hydrothermal cooling is revealed, with venting along the western boundary fault of the trough. In the southern trough an analogous pattern is apparently superimposed upon a conductive cooling anomaly associated with a recent central intrusion. The discharge of thermal waters occurs along the boundary faults and through other faults associated with a possible horst block located in the north central floor of the southern trough. The heat flow patterns suggest that the intrusions are episodic and do not occur simultaneously along the length (15–40 km) of a spreading segment. A review of all available heat flow measurements for the Guaymas basin suggests that most of the recharge for a pervasive regional hydrothermal system is limited to the central depressions, with perhaps some contribution from pore water. The discharge of thermal waters occurs predominantly in the central depressions and possibly along the boundary transform faults and fracture zones. The regions of the basin more than a few kilometers in distance from the spreading axis, although presumably underlain by a hydrothermal system, are probably not the location of numerous vents or recharge zones

Band structure of semimagnetic Hg1-yMnyTe quantum wells

The band structure of semimagnetic Hg_1-yMn_yTe/Hg_1-xCd_xTe type-III quantum wells has been calculated using eight-band kp model in an envelope function approach. Details of the band structure calculations are given for the Mn free case (y=0). A mean field approach is used to take the influence of the sp-d exchange interaction on the band structure of QW's with low Mn concentrations into account. The calculated Landau level fan diagram and the density of states of a Hg_0.98Mn_0.02Te/Hg_0.3Cd_0.7Te QW are in good agreement with recent experimental transport observations. The model can be used to interpret the mutual influence of the two-dimensional confinement and the sp-d exchange interaction on the transport properties of Hg_1-yMn_yTe/Hg_1-xCd_xTe QW's.Comment: 12 pages, 4 figure