The Effect of ACE Inhibition on the Pulmonary Vasculature in Combined Models of Chronic Hypoxia and Pulmonary Arterial Banding in Sprague Dawley Rats

Microfocal CT was used to image the pulmonary arterial (PA) tree in rodent models of pulmonary hypertension (PH). CT images were used to measure the arterial tree diameter along the main arterial trunk at several hydrostatic intravascular pressures and calculate distensibility. High-resolution planar angiographic imaging was also used to examine distal PA microstructure. Data on pulmonary artery tree morphology improves our understanding of vascular remodeling and response to treatments. Angiotensin II (ATII) has been identified as a mediator of vasoconstriction and proliferative mitotic function. ATII has been shown to promote vascular smooth muscle cell hypertrophy and hyperplasia as well as stimulate synthesis of extracellular matrix proteins. Available ATII is targeted through angiotensin converting enzyme inhibitors (ACEIs), a method that has been used in animal models of PH to attenuate vascular remodeling and decrease pulmonary vascular resistance. In this study, we used rat models of chronic hypoxia to induce PH combined with partial left pulmonary artery occlusion (arterial banding, PLPAO) to evaluate effects of the ACEI, captopril, on pulmonary vascular hemodynamic and morphology. Male Sprague Dawley rats were placed in hypoxia (FiO2 0.1), with one group having underwent PLPAO three days prior to the chronic hypoxia. After the twenty-first day of hypoxia exposure, treatment was started with captopril (20 mg/kg/day) for an additional twenty-one days. At the endpoint, lungs were excised and isolated to examine: pulmonary vascular resistance, ACE activity, pulmonary vessel morphology and biomechanics. Hematocrit and RV/LV+septum ratio was also measured. CT planar images showed less vessel dropout in rats treated with captopril versus the non-treatment lungs. Distensibility data shows no change in rats treated with captopril in both chronic hypoxia (CH) and CH with PLPAO (CH+PLPAO) models. Hemodynamic measurements also show no change in the pulmonary vascular resistance with captopril treatment in both CH and CH+PLPAO

Heat transfer of a single wall carbon nanotube

A non equilibrium molecular dynamics simulation was used to calculate thermal conductivity of a single-walled carbon nanotube (SWNT). Effective thermal conductivity was calculated for the same SWNT surrounded by nitrogen at 250K and 290K at 8 bar. Heat flux was created by implementing Nose-Hoover thermostats at the ends of the SWNT. Using Fourier's Law thermal conductivity was calculated. For both simulations thermal conductivity increased when the temperature difference between the two ends was small. As the temperature difference increased the thermal conductivity reached a constant value of around 160 W/mK in a vacuum with end temperatures close to 330K or 310 K

Contributors to Dining Satisfaction of Residence Hall Students

Early writings on university housing show a connection between dining services and university residence halls (Riker & Lopez, 1 96 1 ) Regardless of how housing and dining programs are organized within the institution, the two entities are inevitably connected; living and eating go together. A recent annual study (Educational Benchmarking, Inc. (EBI), 2002) comparing four years of data cited satisfaction with dining as being one of the foremost predictors of overall residence satisfaction. This prominent relationship provides incentive for housing administrators to be more aware of students\u27 dining satisfaction. The purpose of this research was to examine contributors to residence hall students\u27 dining satisfaction at a large Midwestern university

Low Profile, Dual-Polarised Antenna for Aeronautical and Land Mobile Satcom

High data rate communications on the move is fastly becoming a major application area for satellite systems using Ku- and higher frequency bands. The ground terminal antenna used in such systems has a profound impact on the system capabilities and is constrained in many often conflicting ways. While simple reflector systems offer the lowest cost solution, there is a widespread need for low profile antennas to minimize the antenna visual signature and to satisfy aesthetic and transportation requirements. It is often considered that the use of such antennas will compromise the system performance

Cementitious Compositions

The invention provides a cementitious composition comprising a cement component comprising (i) an accelerant, (ii) a calcium sulphate source and (iii) an ettringite forming cement; an aggregate; and optionally water; wherein the cement has a minimum unconfined compressive strength of 1500 psi when tested in accordance with ASTM C1140 and/or C1604 at 15 minutes after placement; methods for its use and concrete formed from it