Heteroepitaxy of 3-5 compound semiconductors on insulating substrates Interim report

Heteroepitaxial growth of GaAs films on aluminum oxide substrates by trimethylgallium-arsine proces

Musculoskeletal Modeling Analysis of Knee Joint Loading During Uphill and Downhill Waling In Patients with Total Knee Replacement

The purposes of these studies were to determine differences in total (TCF), medial (MCF) and lateral (LCF) tibiofemoral compartment compressive forces and related muscle forces between limbs (replaced, non-replaced, and control), and different slopes during uphill [0° (level), 5°, 10°], and downhill [0° (level), 5° 10°] using statistical parametric mapping (SPM). Static optimization was used to determine muscle and compressive forces for 9 patients with total knee arthroplasty (TKA) and 9 control participants during walking trials. Total , loading-response, and push-off TCF impulse were calculated. A 3×3 [Limb (replaced, non-replaced, control] × Slope (0°, 10°, 15°)] SPM[F] repeated measures ANOVA was conducted independently for both uphill and downhill walking. Independent 3×3 (Limb × Slope]) mixed-model ANOVA were used to detect differences for TCF impulse for both up- and downhill walking. For study one, significant between-limb differences were observed for MCF during 23-30% stance between replaced and control limbs. Significant differences between slopes were observed for all variables, except knee flexor muscle force. TCF impulse indicates that joint load is greater for all limbs as slope increases. A small sample size of patients with TKA who utilize different gait strategies may have rendered difference between limbs non-significant. For study two, significant differences were found for TCF, MCF, and knee flexor muscle forces between replaced and control limbs during early loading-response (1‑5% stance). No significant differences were found between limbs for MCF or LCF, suggesting that TKA may have been successful in correcting errant frontal plane alignment. Loading-response TCF impulse increased with increasing slope yet push-off TCF impulse decreased with increasing decline slope suggesting decreased knee joint loading during push-off while not having to overcome gravity. Uphill walking may be an effective exercise for high intensity early and long-term rehabilitation programs with increased muscular demand and quadriceps strengthening as slope increases while promoting the reacquisition of normal gait patterns following TKA. Downhill walking facilitates increased muscular demand and quadriceps strengthening via eccentric contractions while regaining normal gait patterns following TKA. Downhill walking, therefore, may be an effective exercise for high intensity early and long-term rehabilitation

Sensitive Coverage Saves Lives: Improving media portrayal of suicidal behaviour

The report outlines the results of consultations with journalists, suicide prevention agencies and mental health groups conducted by the journalism ethics charity MediaWise. It makes recommendations for action by media organisations and suicide prevention agencies

The Impact of Lidar Detection Sensitivity on Assessing Aerosol Direct Radiative Effects

Spaceborne lidar observations have great potential to provide accurate global estimates of the aerosol direct radiative effect (DRE) in both clear and cloudy conditions. However, comparisons between observations from the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite (CALIPSO) and multiple years of Atmospheric Radiation Measurement (ARM) programs ground-based Raman lidars (RL) show that CALIPSO does not detect all radiatively significant aerosol, i.e. aerosol that directly modifies the Earths radiation budget. We estimated that using CALIPSO observations results in an underestimate of the magnitude of the global mean aerosol DRE by up to 54%. The ARM RL datasets along with NASA Langley airborne high spectral resolution lidar (HSRL) data from multiple field campaigns are used to compute the detection sensitivity required to accurately resolve the aerosol DRE. This shows that a lidar with a backscatter coefficient detection sensitivity of about 12x10(exp -4)km(exp -1)sr(exp -1) at 532nm would resolve all the aerosol needed to derive the DRE to within 1%

Social Conditions of Nebraska\u27s Elderly

In 1991, the authors conducted a study of 500 older Nebraskans, comparing 300 people in Omaha and its surrounding counties with a sample of 200 who lived in the very rural Sandhills counties. The purpose of that study was to compare health and health care experience and satisfaction between urban and rural-dwelling elders. Random samples of older people were identified and interviewed by trained telephone operators; each interview took about a half hour. People were asked about their experiences with health and illness, the distance to their primary source of medical care and the distance to the hospital they use, their levels of satisfaction with that health care provider and hospital, their experience with dental care and satisfaction with it, and a number of questions dealing with their health beliefs. Levels of functioning and disability were also assessed through activities of daily living scales

Neutral gas in Lyman-alpha emitting galaxies Haro 11 and ESO 338-IG04 measured through sodium absorption

Context. The Lyman alpha emission line of galaxies is an important tool for finding galaxies at high redshift, and thus probe the structure of the early universe. However, the resonance nature of the line and its sensitivity to dust and neutral gas is still not fully understood. Aims. We present measurements of the velocity, covering fraction and optical depth of neutral gas in front of two well known local blue compact galaxies that show Lyman alpha in emission: ESO 338-IG 04 and Haro 11. We thus test observationally the hypothesis that Lyman alpha can escape through neutral gas by being Doppler shifted out of resonance. Methods. We present integral field spectroscopy from the GIRAFFE/Argus spectrograph at VLT/FLAMES in Paranal, Chile. The excellent wavelength resolution allows us to accurately measure the velocity of the ionized and neutral gas through the H-alpha emission and Na D absorption, which traces the ionized medium and cold interstellar gas, respectively. We also present independent measurements with the VLT/X-shooter spectrograph which confirm our results. Results. For ESO 338-IG04, we measure no significant shift of neutral gas. The best fit velocity is -15 (16) km/s. For Haro 11, we see an outflow from knot B at 44 (13) km/s and infalling gas towards knot C with 32 (12) km/s. Based on the relative strength of the Na D absorption lines, we estimate low covering fractions of neutral gas (down to 10%) in all three cases. Conclusions. The Na D absorption likely occurs in dense clumps with higher column densities than where the bulk of the Ly-alpha scattering takes place. Still, we find no strong correlation between outflowing neutral gas and a high Lyman alpha escape fraction. The Lyman alpha photons from these two galaxies are therefore likely escaping due to a low column density and/or covering fraction.Comment: 9 pages, 3 figure

Data-driven prediction of vortex-induced vibration response of marine risers subjected to three-dimensional current

Slender marine structures such as deep-water marine risers are subjected to currents and will normally experience Vortex Induced Vibrations (VIV), which can cause fast accumulation of fatigue damage. The ocean current is often three-dimensional (3D), i.e., the direction and magnitude of the current vary throughout the water column. Today, semi-empirical tools are used by the industry to predict VIV induced fatigue on risers. The load model and hydrodynamic parameters in present VIV prediction tools are developed based on two-dimensional (2D) flow conditions, as it is challenging to consider the effect of 3D flow along the risers. Accordingly, the current profiles must be purposely made 2D during the design process, which leads to significant uncertainty in the prediction results. Further, due to the limitations in the laboratory, VIV model tests are mostly carried out under 2D flow conditions and thus little experimental data exist to document VIV response of riser subjected to varying directions of the current. However, a few experiments have been conducted with 3D current. We have used results from one of these experiments to investigate how well 1) traditional and 2) an alternative method based on a data driven prediction can describe VIV in 3D currents. Data driven modelling is particularly suited for complicated problems with many parameters and non-linear relationships. We have applied a data clustering algorithm to the experimental 3D flow data in order to identify measurable parameters that can influence responses. The riser responses are grouped based on their statistical characteristics, which relate to the direction of the flow. Furthermore we fit a random forest regression model to the measured VIV response and compare its performance with the predictions of existing VIV prediction tools (VIVANA-FD).Comment: 12 pages, presented at Norwegian AI Society Symposium 2019, accepted for publication in Springer Conference Proceeding

The Effects of Higher and Lower CO2 Levels in the Atmosphere on the Photosynthetic Rates and Stomatal Conductance of Malosma laurina in The Santa Monica Mountains

We hypothesize that higher CO2 levels will lead to a change in photosynthetic performance in the Malosma laurina population of the Santa Monica Mountains. We used one Malosma laurina that is across the street from university’s theme tower. We chose this specific plant because it was in the sun and it was in a well irrigated area. We selected a plant that is in non-shaded areas at 12:00 pm and then dark adapt them for 20 minutes. We selected an adult plant that was between four and six feet tall. We took the measurements from the upper leaves of the plant. We measured the photosynthetic rates of the plant, which will be exposed to the unaltered CO2 levels of the natural environment in the Santa Monica Mountains. Then, we used the LICOR (Li- 6400) system to create create three separate environments that we will then impose on the same plant but using different leaves. These simulated environments will have CO2 levels of 280ppm (past atmospheric level of CO2 before the industrial revolution), 400ppm (current atmospheric level of CO2), and 800ppm (expected atmospheric level of CO2 by 2100)