18 research outputs found

    EMI / EMC Design for Class D Payloads (Resource Prospector / NIRVSS)

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    EMI/EMC techniques are applied to a Class D instrument (NIRVSS) to achieve low noise performance and reduce risk of EMI/EMC testing failures and/or issues during system integration and test. Basic techniques are not terribly expensive or complex, but do require close coordination between electrical and mechanical staff early in the design process. Low-cost methods to test subsystems on the bench without renting an EMI chamber are discussed. This method was applied to the NIRVSS instrument and achieved improvements up to 59dB on conducted emissions measurements between hardware revisions

    Junior Recital

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    List of performers and performances

    Association of Inactive Myostatin in Piedmontese-Influenced Steers and Heifers on Performance and Carcass Traits at Different Endpoints

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    Performance and carcass traits were evaluated using Piedmontese-influenced calf-fed steers and yearling heifers genotyped for zero, one, or two copies (homozygous active, heterozygous, or homozygous inactive, respectively) of the inactive myostatin allele. Steers and heifers had similar responses across genotypes in performance and carcass traits evaluated at different endpoints. Inactive myostatin decreased DMI, final BW (live), and ADG (live). Increased dressing percentage resulted in increased carcass-adjusted ADG and improved feed conversion for cattle with inactive myostatin. Cattle with inactive myostatin are leaner with larger LM area when finished to equal carcass weight

    BioSentinel: Mission Summary and Lessons Learned From the First Deep Space Biology CubeSat Mission

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    Launched on Artemis I, BioSentinel carries a biology experiment into deep space for the first time in 50 years. A 6U CubeSat form factor was utilized for the spacecraft, which included technologies newly developed or adapted for operations beyond Earth orbit. The spacecraft carries onboard budding yeast, Saccharomyces cerevisiae, as an analog to human cells to test the biological response to deep space radiation. This was the maiden deep-space voyage for many of the subsystems, and the first time to evaluate their performance in flight operation. Flying a CubeSat beyond LEO comes with unique challenges with respect to trajectory uncertainty and mission operations planning. The nominal plan was a lunar fly-by, followed by an insertion into heliocentric orbit. However, some possible scenarios included lunar eclipses that could have severely impacted the power budget during that phase of the mission, while others could have resulted in a “retrograde” hyperbola at swing-by resulting in the spacecraft traveling inward toward Earth or even towards a collision with the lunar surface. The commissioning phase of the mission was successful and completed a week ahead of schedule. It did not come without its exciting moments and challenges. First contact with the spacecraft uncovered that the vehicle was unexpectedly tumbling after deployment, a situation that needed to be corrected urgently. The mission operations team executed a contingency plan to stabilize the spacecraft, with just moments to spare before the battery ran out of power. The BioSensor payload onboard the spacecraft is a complex instrument that includes microfluidics, optical systems, sensor control electronics, as well as the living yeast cells. BioSentinel also includes a TimePix radiation sensor implemented by JSC’s RadWorks group. Total dose and Linear Energy Transfer (LET) spectrum data are compared to the rate of cell growth and metabolic activity measured in the S. cerevisiae cells. BioSentinel mature nanosatellite technologies included: deep space communications and navigation, autonomous attitude control and momentum management, and micro-propulsion systems, to provide an adaptable nanosatellite platform for deep space uses. This paper discusses the performance of the BioSentinel spacecraft through the mission phase, and includes lessons learned from challenges and anomalies. BioSentinel had many successes and will be a pathfinder for future deep space CubeSats and biology missions

    Predictors of Poor Perinatal Outcome following Maternal Perception of Reduced Fetal Movements: A Prospective Cohort Study

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    Background Maternal perception of reduced fetal movement (RFM) is associated with increased risk of stillbirth and fetal growth restriction (FGR). RFM is thought to represent fetal compensation to conserve energy due to insufficient oxygen and nutrient transfer resulting from placental insufficiency. Objective To identify predictors of poor perinatal outcome after maternal perception of reduced fetal movements (RFM). Design Prospective cohort study. Methods 305 women presenting with RFM after 28 weeks of gestation were recruited. Demographic factors and clinical history were recorded and ultrasound performed to assess fetal biometry, liquor volume and umbilical artery Doppler. A maternal serum sample was obtained for measurement of placentally-derived or modified proteins including: alpha fetoprotein (AFP), human chorionic gonadotrophin (hCG), human placental lactogen (hPL), ischaemia-modified albumin (IMA), pregnancy associated plasma protein A (PAPP-A) and progesterone. Factors related to poor perinatal outcome were determined by logistic regression. Results 22.1% of pregnancies ended in a poor perinatal outcome after RFM. The most common complication was small-for-gestational age infants. Pregnancy outcome after maternal perception of RFM was related to amount of fetal activity while being monitored, abnormal fetal heart rate trace, diastolic blood pressure, estimated fetal weight, liquor volume, serum hCG and hPL. Following multiple logistic regression abnormal fetal heart rate trace (Odds ratio 7.08, 95% Confidence Interval 1.31–38.18), (OR) diastolic blood pressure (OR 1.04 (95% CI 1.01–1.09), estimated fetal weight centile (OR 0.95, 95% CI 0.94–0.97) and log maternal serum hPL (OR 0.13, 95% CI 0.02–0.99) were independently related to pregnancy outcome. hPL was related to placental mass. Conclusion Poor perinatal outcome after maternal perception of RFM is closely related to factors which are connected to placental dysfunction. Novel tests of placental function and associated fetal response may provide improved means to detect fetuses at greatest risk of poor perinatal outcome after RFM

    The effects of IQPLUS Focus on cognitive function, mood and endocrine response before and following acute exercise

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    BACKGROUND: Phosphatidylserine (PS) is a phospholipid found in cell membranes of most animals and plants. PS has been shown to reduce stress and increase performance in runners, cyclists and golfers. The purpose of this study was to investigate the effects of a PS containing formulation on cognitive function, mood and endocrine response before and after intense resistance exercise. METHODS: 18 lower body, resistance trained, college aged males ingested 14 days of supplement (IQPLUS Focus, providing 400 mg of soy-derived PS) and a Placebo (PL), in a randomized, double-blind, placebo controlled, cross-over manner. Following 14 days of supplementation, participants performed an acute bout of lower body resistance training. Mood (Profile of Mood States, POMS) and cognitive function (Serial Subtraction Test, SST) were measured prior to, 5 minutes after, and 60 minutes after exercise. Venous blood samples were collected prior to, and 5, 15, 25, 40 and 60 minutes after exercise. Blood samples were analyzed for plasma cortisol and testosterone. Data were analyzed using repeated measures ANOVA. RESULTS: PS supplementation significantly reduced the time needed for a correct calculation on the SST by 20% (reduced by 1.27 s per calculation; PL: 6.4 s, PS: 5.13 s; p = 0.001), and reduced the total amount of errors by 39% (PL: 1.28 + .69, PS: .78 + .27, p = 0.53), and increased the amount of correct calculations by 13% (PL: 22.1 + 2.24, PS: 24.9 + 1.52, p = 0.07) prior to or in response to exercise compared to PL. Following exercise, there was no difference in SST scores between PS and PL. There were no significant changes in regards to mood or endocrine response to exercise as a result of PS supplementation. CONCLUSION: PS supplementation significantly increased cognitive function prior to exercise. Improved cognitive function could benefit athletes and non-athletes alike. PS did not appear to affect mood or endocrine response prior to or following resistance exercise

    Effects of Roughage Source and Level with the Inclusion of Wet Distillers Grains on Ruminal Metabolism and Nutrient Digestibility

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    Six ruminally cannulated steers were used in a 6 x 6 Latin square with treatments arranged as a 2 x 3 factorial with alfalfa hay or cornstalks included at a normal, low or zero level on an equal neutral detergent fiber (NDF) basis. The base finishing diet contained 30% wet distillers grains plus solubles (WDGS). No source x level interactions were observed. Roughage source had no effect on nutrient intake, dry matter (DM) and organic matter (OM) digestibility or ruminal pH. Digestibility of NDF tended to be higher for alfalfa hay compared to cornstalks. Ruminal pH, DMI and NDF intake increased linearly while nutrient digestibility decreased linearly as roughage level increased. These data indicate that in finishing diets containing 30% wet distillers grains plus solubles (WDGS) roughages can be exchanged on an equal NDF basis and it is not beneficial to completely eliminate roughage sources from the diet

    Forage Quality and Grazing Performance of Beef Cattle Grazing Brown Midrib Grain Sorghum Residue

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    Two hybrids of grain sorghum, the AWheatland x RTx430 hybrid (CON) and its near isogenic brown midrib counterpart (BMR), were used in a 65-day residue grazing experiment. Grain sorghum was planted in 4 replications for each treatment within the same field, and grazed with 6 steers/replication. Samples of the sorghum residue were collected on days 1, 31, and 60 for neutral detergent fiber (NDF) and in vitro NDF digestibility analysis. Steers grazing the BMR treatment gained 1.55 lb/day while the steers grazing the CON treatment gained 1.32 lb/day (P = 0.14). The BMR and CON were similar in NDF (73.5%), but in vitro NDF digestibility increased by 9.9 percentage units in the leaf portion
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