Quantum Hall criticality and localization in graphene with short-range impurities at the Dirac point.

We explore the longitudinal conductivity of graphene at the Dirac point in a strong magnetic field with two types of short-range scatterers: adatoms that mix the valleys and "scalar" impurities that do not mix them. A scattering theory for the Dirac equation is employed to express the conductance of a graphene sample as a function of impurity coordinates; an averaging over impurity positions is then performed numerically. The conductivity σ is equal to the ballistic value 4e2/πh for each disorder realization, provided the number of flux quanta considerably exceeds the number of impurities.

Measurement of the cascade transition via the first excited state of 16O in the 12C(alpha,gamma)16O reaction, and its S factor in stellar helium burning.

Radiative alpha-particle capture into the first excited, J(pi)=0+ state of 16O at 6.049 MeV excitation energy has rarely been discussed as contributing to the 12C(alpha,gamma)16O reaction cross section due to experimental difficulties in observing this transition. We report here measurements of this radiative capture in 12C(alpha,gamma)16O for center-of-mass energies of E=2.

[Quality assurance of outpatient nursing services in Baden-Württemberg -- overall view of 6 years of a total survey by the Medical Services of the Statutory Health Insurance (MDK)].

During the years 1997 to 2003 the medical services of the statutory health insurance in the German Federal State of Baden-Württemberg carried out a total survey regarding structure, process and outcome with regard to the quality of care of outpatients in the German long-term care insurance system. This survey provides information on the development of the quality of care. All outpatient nursing services licensed by the statutory long-term care insurance funds in Baden-Württemberg (n (1997 - 2000) = 863; n (2000 - 2003) = 779) were subjected to a uniform assessment based on a consented concept applied in all German Federal States.

Effect of peri-operative diltiazem on myocardial ischaemia and function in patients receiving mammary artery grafts.

A prospective, randomized study was performed with 66 patients undergoing elective coronary bypass surgery involving internal mammary artery (IMA) grafts to the left anterior descending artery (LAD). Patients received a continuous peri-operative infusion of either diltiazem (0.1 mg.

Shed blood autotransfusion influences ischemia-sensitive laboratory parameters after coronary operations.

The diagnostic significance of ischemia-sensitive laboratory parameters in respect to possible interference with shed blood autotransfusion was assessed in a prospective study with 100 patients undergoing elective coronary artery bypass grafting. Serum levels of creatine kinase, creatine kinase MB activity, creatine kinase MB mass concentration, 2-hydroxybutyrate dehydrogenase, lactate dehydrogenase-1, troponin-T, myoglobin, and glutamicoxaloacetic transaminase were repeatedly assessed up to the sixth postoperative day. Thirty-seven patients were excluded from the study due to postoperative development of myocardial infarction (n = 4), transient ischemic events (n = 25), and left bundle-branch blocks (n = 8).

Effects of diltiazem on perioperative ischemia, arrhythmias, and myocardial function in patients undergoing elective coronary bypass grafting.

A prospective, randomized study was performed on 120 patients undergoing elective coronary bypass grafting to define the effect of the calcium channel blocker diltiazem on perioperative ischemia, arrhythmias, and myocardial function. Patients received a continuous 24-hour perioperative infusion of either diltiazem (0.1 mg/kg per hour, n = 60) or nitroglycerin (1 micrograms/kg per minute, n = 60).

Diltiazem provides anti-ischemic and anti-arrhythmic protection in patients undergoing coronary bypass grafting.

In 91 patients undergoing elective coronary bypass grafting, the anti-ischemic and anti-arrhythmic efficacy of a 24-hour infusion of either the calcium antagonist diltiazem (0.1 mg/kg per h, n = 44) or nitroglycerin (1 micrograms/kg per min, n = 47) were compared. Myocardial ischemia was diagnosed by Holter monitoring and the repeated assessment of 12-lead ECG and serum enzyme levels and defined as a transient ischemic event, transient coronary spasm or myocardial infarction.

The influence of obesity on perioperative morbidity: retrospective study of 502 aortocoronary bypass operations.

The incidence of perioperative complications after coronary artery surgery was investigated by a retrospective study of all 502 patients undergoing coronary artery bypass graft (CABG) surgery in our Department between January 1st and December 31st of last year (1990). Furthermore, the influence of obesity on the early results of surgery was assessed and the effect of preoperative weight reduction on perioperative complication rates examined. Obese patients had a greater incidence of left-stem coronary artery stenosis (p less than 0.