Solidification of Ni-Re Peritectic Alloys.

Differential thermal analysis (DTA) and microstructural and microprobe measurements of DTA and as-cast Ni-Re alloys with compositions between 0.20 and 0.44 mass fraction Re provide information to resolve differences in previously published Ni-Re phase diagrams. This investigation determines that the peritectic invariant between liquid, Re-rich hexagonal close packed and Ni-rich face center cubic phases, L + HCP → FCC, occurs at 1561.1 °C ± 3.4 °C (1σ) with compositions of liquid, FCC and HCP phases of 0.283 ± 0.036, 0.436 ± 0.026, and 0.828 ± 0.037 mass fraction Re, respectively. Analysis of the microsegregation in FCC alloys yields a partition coefficient for solidification, k = 1.54 ± 0.09 (mass frac./mass frac.). A small deviation from Scheil behavior due to dendrite tip kinetics is documented in as-cast samples. No evidence of an intermetallic phase is observed.

Associations between osteoporosis and coronary artery disease in postmenopausal women.

OBJECTIVE: Coronary artery disease (CAD) and osteoporosis are major causes of mortality and morbidity in postmenopausal women. We aimed to investigate the association between osteoporosis and CAD in asymptomatic postmenopausal women at a single center. METHODS: This study included 863 postmenopausal women without histories of cardiovascular diseases who visited the Health Promotion Center from June 1, 2004 to May 31, 2015. All subjects were screened for bone mineral density (BMD) by dual-energy X-ray absorptiometry and for the degree of CAD by multidetector computed tomography. RESULTS: Low BMD including osteopenia and osteoporosis was found to be significantly associated with old age, low body mass index, and a higher prevalence of diabetes mellitus. The incidences of CAD including a high coronary artery calcium score (≥100), obstructive coronary artery disease, and multivessel disease were significantly higher in subjects with low BMD. After adjusting for age and cardiovascular risk factors, osteoporosis was associated with a high coronary artery calcium score (p = 0.015) and with obstructive coronary artery disease (p = 0.002). There was a trend toward significance with multivessel disease (p = 0.052). CONCLUSIONS: High coronary artery calcium score and obstructive coronary artery disease, as revealed by multidetector computed tomography, were associated with osteoporosis in asymptomatic postmenopausal women, independent of cardiovascular risk factors and age.

Tailoring the topology of an artificial magnetic skyrmion.

Despite theoretical predictions, it remains an experimental challenge to realize an artificial magnetic skyrmion whose topology can be well controlled and tailored so that its topological effect can be revealed explicitly in a deformation of the spin textures. Here we report epitaxial magnetic thin films in which an artificial skyrmion is created by embedding a magnetic vortex into an out-of-plane aligned spin environment. By changing the relative orientation between the central vortex core polarity and the surrounding out-of-plane spins, we are able to control and tailor the system between two skyrmion topological states. An in-plane magnetic field is used to annihilate the skyrmion core by converting the central vortex state into a single domain state. Our result shows distinct annihilation behaviour of the skyrmion core for the two different skyrmion states, suggesting a topological effect of the magnetic skyrmions in the core annihilation process.

Apparent treatment-resistant hypertension among elderly Korean hypertensives: an insight from the HIT registry.

The aim of this study was to determine the clinical characteristics of patients with resistant hypertension (RH) and predictors among elderly Korean hypertensives. This prospective, multi-center, observational study evaluated 2439 elderly hypertensive patients between December 2008 and November 2011, who visited secondary hypertension clinics for high blood pressure (BP). Patients were categorized as resistant if their BP was ≥140/90 mm Hg and if they reported using antihypertensive medications from three different drug classes, including a diuretic or drugs from ≥4 antihypertensive drug classes, regardless of BP. Characteristics of patients with RH were compared with those of patients who were controlled with one or two antihypertensive medications after 6-month antihypertensive treatment. In comparison with 837 patients with non-RH, 404 patients with RH were more likely to be aware of their status of high BP before enrollment and have a high baseline systolic BP ≥160 mm Hg, microalbuminuria, high body mass index (BMI) ≥24 kg m(-2) and diabetes mellitus (DM). In drug-naive patients, awareness of hypertension at baseline was the only independent predictor for RH. In elderly Korean hypertensives, BMI (≥24 kg m(-2)), baseline systolic BP (≥160 mm Hg), microalbuminuria, DM and awareness of hypertension showed an association with RH.

Cardiovascular autonomic dysfunction predicts acute ischaemic stroke in patients with Type 2 diabetes mellitus: a 7-year follow-up study.

AIMS: We investigated whether cardiovascular autonomic neuropathy (CAN) is associated with acute ischaemic stroke in patients with Type 2 diabetes. METHODS: From 1999 to 2000, cardiovascular autonomic function tests were conducted in patients with Type 2 diabetes (n = 1458). Patients were followed up between 2006 and 2007. Standard tests for CAN measured heart rate variability parameters [expiration-to-inspiration (E/I) ratio, responses to the Valsalva manoeuvre and standing]. Using the American Diabetes Association criteria, the CAN scores were determined from the results of each test as follows: 0 = normal, 1 = abnormal (total maximum score 3). We assessed the development of acute ischaemic stroke events. RESULTS: The prevalence of CAN at baseline was 55.7% (E/I 17.1%, Valsalva 39.4%, posture 27.3%) (n = 1126). During follow-up, 131 patients (11.6%) developed acute ischaemic stroke. The vascular events were more frequent in older patients (P < 0.001) and in those with diabetes of longer duration (P = 0.022), hypertension (P < 0.001) or diabetic retinopathy (P = 0.03) than in patients without vascular events. Patients with ischaemic stroke had higher creatinine levels (P = 0.045) and higher urine albumin excretion (P = 0.025) than those of patients without stroke. Cox proportional hazard regression analysis revealed that the CAN score was associated with the development of acute ischaemic stroke (total score 0 vs. 3, adjusted hazard ratio 2.7, 95% CI 1.3-5.5, P = 0.006). CONCLUSION: Cardiovascular autonomic dysfunction was significantly associated with the development of ischaemic stroke in patients with Type 2 diabetes.

Do the extent and direction of arterial remodelling predict subsequent progression of coronary atherosclerosis? A serial intravascular ultrasound study.

OBJECTIVE: Despite the link between positive coronary remodelling and acute ischaemic events, no data exist about the impact of arterial remodelling on subsequent progression of coronary atherosclerosis. The objective of this study was to examine whether extent and direction of arterial remodelling are predictors of progression of coronary atherosclerosis. DESIGN, SETTING AND PATIENTS: From the Reversal of Atherosclerosis with Aggressive Lipid Lowering (REVERSAL) trial, 210 focal coronary lesions (single lesion per patient) were identified with