Scale-invariant magnetoresistance in a cuprate superconductor.

The anomalous metallic state in the high-temperature superconducting cuprates is masked by superconductivity near a quantum critical point. Applying high magnetic fields to suppress superconductivity has enabled detailed studies of the normal state, yet the direct effect of strong magnetic fields on the metallic state is poorly understood. We report the high-field magnetoresistance of thin-film La2-x Sr x CuO4 cuprate in the vicinity of the critical doping, 0.161 ≤ p ≤ 0.190. We find that the metallic state exposed by suppressing superconductivity is characterized by magnetoresistance that is linear in magnetic fields up to 80 tesla. The magnitude of the linear-in-field resistivity mirrors the magnitude and doping evolution of the well-known linear-in-temperature resistivity that has been associated with quantum criticality in high-temperature superconductors.

Three axis vector magnet set-up for cryogenic scanning probe microscopy.

We describe a three axis vector magnet system for cryogenic scanning probe microscopy measurements. We discuss the magnet support system and the power supply, consisting of a compact three way 100 A current source. We obtain tilted magnetic fields in all directions with maximum value of 5T along z-axis and of 1.2T for XY-plane magnetic fields. We describe a scanning tunneling microscopy-spectroscopy (STM-STS) set-up, operating in a dilution refrigerator, which includes a new high voltage ultralow noise piezodrive electronics and discuss the noise level due to vibrations. STM images and STS maps show atomic resolution and the tilted vortex lattice at 150 mK in the superconductor ß-Bi2Pd. We observe a strongly elongated hexagonal lattice, which corresponds to the projection of the tilted hexagonal vortex lattice on the surface. We also discuss Magnetic Force Microscopy images in a variable temperature insert.

[Captopril in single doses in the treatment mild-moderated arterial hypertension]. / Captopril en dosis única en el tratamiento de la hipertensión arterial ligera-moderada.

The effect of single dose (50 mg) Captopril (C) used either alone or associated to diuretics (50 mg hydrochlorothiazide -HCTI) in the treatment of mild-moderate essential arterial hypertension was studied in a multicentric study. Eighty eight patients were chosen. After a minimum of 4 month follow-up period 53.4% responded (BDP less than 95 mm Hg) to single dose C (group 1:47 patients), 89.77% to 50 mg C in single dose together with 50 mg HTIT (group 2: 32 patients), 95.45% of two 50 mg doses of C and 50 mg HCIT (group 3: 5 patients), and 97.72% responded to 3 doses of C and 50 mg of HCTI (group 4: 2 patients). The decrease in blood pressure values was statistically significant (p, 000, Wilcoxon test) in groups 1 and 2, having a mean decrease in blood pressure (BP) of 14%. In group 1 (n = 42) the SBP which initially was 165.72 +/- 11.32, decreased to 148.28 +/- 11.5 and the DBP decreased from 101.55 +/- 5.68 to 87.28 +/- 6.59. In group 2 (n = 32) the SBP decreased from 173.50 +/- 14.08 to 152.44 +/- 20.8 and the DBP from 103.34 +/- 5.29 to 87.47 +/- 6.39. The response to monotherapy could not be statistically correlated either to early essential hypertension or to the patients age. Treatment was discontinued in three cases due to the secondary effects, cough, ageusia and nervousness, showing the remaining patients a good tolerance. No changes were observed in the analytical parameters. This study shows the usefulness and tolerance of single dose C as the initial treatment of mild to moderate essential hypertension.