Probability of At Least One High Arterial Blood Pressure Measurement in Elderly Patients with Healthy Vascular Aging in Two Years of Follow-Up

Background/Aims: Elderly patients with normal systemic arterial blood pressure associated with femoral carotid pulse velocity (cf-PWV) less than 7.6 m/s and without associated comorbidities are considered to have good vascular health. The aim of the current study was to verify the probability that elderly patients with good vascular health have at least one blood pressure measurement above the different thresholds for systolic blood pressure (120, 130 and 140 mmHg) during two years of follow–up. Methods: We selected 72 normotensive patients (< 140/90 mmHg) without comorbidities and divided them into group A, with cf-PWV < 7.6 m/s (n = 27; 65 ± 4 years), and group B, with cf-PWV ≥ 7.6 m/s (n = 45; 66± 8 years). These patients were followed for two years and were observed in 3 outpatient visits (0, 12 and 24 months). At each visit, the brachial pressures were indirectly measured in triplicate, and applanation tonometry was performed. Results: When group A and group B were compared, the odds ratio (OR) of having a systolic pressure measurement ≥ 140 mmHg in two years of follow-up was 0.22 (P < 0.0001); ≥ 130 mmHg, the OR was 0.49 (P < 0.0007), and ≥ 120 mmHg, the OR was 0.54 (P < 0.001). Group A and group B showed increased values of cf-PWV during the two years of follow-up (P < 0.05). Changes in the average systolic brachial pressure were not significant during the two years in groups A or B. Conclusion: Vascular health in elderly individuals seems to protect against occasional elevations in systemic arterial pressure

Gyrations: The Missing Link Between Classical Mechanics with its Underlying Euclidean Geometry and Relativistic Mechanics with its Underlying Hyperbolic Geometry

Being neither commutative nor associative, Einstein velocity addition of relativistically admissible velocities gives rise to gyrations. Gyrations, in turn, measure the extent to which Einstein addition deviates from commutativity and from associativity. Gyrations are geometric automorphisms abstracted from the relativistic mechanical effect known as Thomas precession

A high performance liquid chromatography method for determination of hydroxyzine hydrochloride in syrup

A simple isocratic method for quantification of hydroxyzine dihydrochloride by HPLC with UV detection at 232 nm in syrup has been developed and validated. Separation was achieved on a C18 column (250 x 4.6 mm, 5 μm) maintained at 90 ºC with 0.5 mol/L potassium dihydrogen phosphate buffer : acetonitrile (1:1, v/v) as mobile phase at a flow rate of 2.0 mL/min. The method was proven to be linear over the range of 80–120 μg/mL, accurate (recovery = 97.8 %), precise (coefficient of variation = 1.52 % for sample) and robust.Colegio de Farmacéuticos de la Provincia de Buenos Aire

n-Hexadecane hydrocracking Single-Event MicroKinetics on Pt/H-beta

[EN] The Single-Event MicroKinetic (SEMK) model constructed for gas-phase hydroconversion of light n-alkanes on large-pore USY zeolites was applied, for the first time, to the hydrocracking of n-hexadecane on a Pt/H-Beta catalyst. Despite the 12-ringed pore channels, shape selectivity was observed in the formation of ethyl side chains. Additionally, heavy feed molecules such as n-hexadecane lead to physisorption saturation of the catalyst pores by strong Van der Waals interactions of the long alkyl chains with the zeolite framework. Intermolecular interactions and packing efficiencies in the pores induce deviations from typical Henry-regime physisorption characteristics as the physisorption selectivity, which is expected to increase with increasing carbon number, appeared to be independent of the latter. Micropore saturation effects were described by the 'size entropy' which quantifies the difference in standard entropy loss between physisorption in the Henry regime and hindered physisorption on a saturated surface. The size entropy is proportional to the catalyst loading with physisorbed species and the adsorbate carbon number. The addition of a size entropy term in the SEMK model, amounting to 102J mol(-1) K-1 for a hexadecane molecule at full saturation, allowed accurately reproducing the contribution of secondary isomerization and cracking reactions, as quantified by means of a contribution analysis. (C) 2012 Elsevier B.V. All rights reserved.This work was funded by the European Research Institute of Catalysis and the European Community’s Sixth Framework Programme. This work was also supported by the Research Board of Ghent University (BOF), the Interuniversity Attraction Poles Programme–Belgian State–Belgian Science Policy and the Long Term Structural Methusalem Funding by the Flemish Government. Financial support by the Comisión Interministerial de Ciencia y Tecnología (CICYT) of Spain through the Project CTQ2010-17988/PPQ is also gratefully acknowledged.Vandegehuchte, BD.; Thybaut, JW.; Martinez Feliu, A.; Arribas Viana, MDLD.; Marin, GB. (2012). n-Hexadecane hydrocracking Single-Event MicroKinetics on Pt/H-beta. Applied Catalysis A General. 441:10-20. doi:10.1016/j.apcata.2012.06.054S102044

Search for a W' boson decaying to a bottom quark and a top quark in pp collisions at sqrt(s) = 7 TeV

Results are presented from a search for a W' boson using a dataset corresponding to 5.0 inverse femtobarns of integrated luminosity collected during 2011 by the CMS experiment at the LHC in pp collisions at sqrt(s)=7 TeV. The W' boson is modeled as a heavy W boson, but different scenarios for the couplings to fermions are considered, involving both left-handed and right-handed chiral projections of the fermions, as well as an arbitrary mixture of the two. The search is performed in the decay channel W' to t b, leading to a final state signature with a single lepton (e, mu), missing transverse energy, and jets, at least one of which is tagged as a b-jet. A W' boson that couples to fermions with the same coupling constant as the W, but to the right-handed rather than left-handed chiral projections, is excluded for masses below 1.85 TeV at the 95% confidence level. For the first time using LHC data, constraints on the W' gauge coupling for a set of left- and right-handed coupling combinations have been placed. These results represent a significant improvement over previously published limits.Comment: Submitted to Physics Letters B. Replaced with version publishe