9,010 research outputs found

    Early Transition and Use of VIIRS and GOES-R Products by NWS Forecast Offices

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    The Visible Infrared Imaging Radiometer Suite (VIIRS) on the NPOESS Preparatory Project (NPP) satellite, part of the Joint Polar Satellite System (JPSS), and the ABI and GLM sensors scheduled for the GOES-R geostationary satellite will bring advanced observing capabilities to the operational weather community. The NASA Short-term Prediction Research and Transition (SPoRT) project at Marshall Space Flight Center has been facilitating the use of real-time experimental and research satellite data by NWS Weather Forecast Offices (WFOs) for a number of years to demonstrate the planned capabilities of future sensors to address particular forecast challenges through improve situational awareness and short-term weather forecasts. For the NOAA GOES-R Proving Ground (PG) activity, SPoRT is developing and disseminating selected GOES-R proxy products to collaborating WFOs and National Centers. SPoRT developed the a pseudo-Geostationary Lightning Mapper product and helped in the transition of the Algorithm Working Group (AWG) Convective Initiation (CI) proxy product for the Hazardous Weather Testbed (HWT) Spring Experiment,. Along with its partner WFOs, SPoRT is evaluating MODIS/GOES Hybrid products, which brings ABI-like data sets from existing NASA instrumentation in front of the forecaster for everyday use. The Hybrid uses near real-time MODIS imagery to demonstrate future ABI capabilities, while utilizing standard GOES imagery to provide the temporal frequency of geostationary imagery expected by operational forecasters. In addition, SPoRT is collaborating with the GOES-R hydrology AWG to transition a baseline proxy product for rainfall rate / quantitative precipitation estimate (QPE) to the OCONUS regions. For VIIRS, SPoRT is demonstrating multispectral observing capabilities and the utility of low-light channels not previously available on operational weather satellites to address a variety of weather forecast challenges. This presentation will discuss the results of transitioning these products to collaborating WFOs throughout the country

    Generation Of Design Equations In Asynchronous Sequential Circuits

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    One step in the synthesis procedure for realizing an asynchronous sequential switching circuit is the generation of next-state and output state equations from a simplified and coded flow table description of the circuit. The usual approach for determining these equations is to first construct a state table from the coded flow table, and then construct transition and output tables. For large flow tables this can be quite a lengthy procedure. This note describes an algorithm which simplifies the synthesis procedure for normal fundamental-mode circuits by permitting the determination of these equations without explicit construction of the state table, transition table, or output table. The algorithm has been programmed in PL/1. Copyright © 1969 by The Institute of Electrical and Electronics Engineers, Inc

    Study of the space environmental effects on spacecraft engineering materials

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    The space environment in which the Space Station Freedom and other space platforms will orbit is truly a hostile environment. For example, the current estimates of the integral fluence for electrons above 1 Mev at 2000 nautical miles is above 2 x 10(exp 10) electrons/sq cm/day. and the proton integral fluence is above 1 x 109 protons/sq cm/day. At the 200 - 400 nautical miles, which is more representative of the altitude which will provide the environment for the Space Station, each of these fluences will be proportionately less; however, the data indicates that the radiation environment will obviously have an effect on structural materials exposed to the environment for long durations. The effects of this combined environment is the issue which needs to be understood for the long term exposure of structures in space. In order to better understand the effect of these hostile phenomena on spacecraft, several types of studies are worth performing in order to simulate at some level the effect of the environment. For example the effect of protons and electrons impacting structural materials are easily simulated through experiments using the Van de Graff and Pelletron accelerators currently housed in the Environmental Effects Facility at MSFC. Proton fluxes with energies of 700 Kev-2.5 Mev can be generated and used to impinge on sample targets to determine the effects of the particles. Also the Environmental Effects Facility has the capability to generate electron beams with energies from 700 Kev to 2.5 Mev. These facilities will be used in this research to simulate space environmental effects from energetic particles. Ultraviolet radiation, particularly in the ultraviolet (less than 400 nm wavelength) is less well characterized at this time. The Environmental Effects Facility has a vacuum system dedicated to studying the effects of ultraviolet radiation on specific surface materials. This particular system was assembled in a previous study (NAS8-38609) in order to perform a variety of experiments on materials proposed for the Space Station. That system has continued to function as planned and has been used in carrying out portions of the proposed study

    Study of micrometeroid orbital debris

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    Knowing the impact effects of the space environment on engineering materials is critical if we are to build space hardware which will last for the duration of the mission. This study will perform measurements on impacted materials in order to determine the effects of the high velocity impacts on structures which are planned for long duration in space

    Study of the space environmental effects on spacecraft engineering materials

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    The issue of the effects of the space environment on spacecraft needs to be understood for the long term exposure of structures in space. In order to better understand the effect of these hostile phenomena on spacecraft, several types of studies are worth performing in order to simulate at some level the effect of the environment. For example the effect of protons and electrons impacting structural materials are easily simulated through experiments using the Van de Graff and Pelletron accelerators currently housed at MSFC. Proton fluxes with energies of 700 KeV - 2.5 MeV can be generated and used to impinge on sample targets to determine the effects of the particles. Also the Environmental Effects Facility at MSFC has the capability to generate electron beams with energies from 700 KeV to 2.5 MeV. These facilities will be used in this research to simulate space environmental effects from energetic particles. Ultraviolet radiation, particularly less than 400 nm wavelength, is less well characterized at this time. The Environmental Effects Facility has a vacuum system dedicated to studying the effects of ultraviolet radiation on specific surface materials. This particular system was assembled in a previous study in order to perform a variety of experiments on materials proposed for the Space Station. That system has continued to function as planned and has been used in carrying out portions of the proposed study

    Phage offer a real alternative

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    The democratic origins of the term "group analysis": Karl Mannheim's "third way" for psychoanalysis and social science.

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    It is well known that Foulkes acknowledged Karl Mannheim as the first to use the term ‘group analysis’. However, Mannheim’s work is otherwise not well known. This article examines the foundations of Mannheim’s sociological interest in groups using the Frankfurt School (1929–1933) as a start point through to the brief correspondence of 1945 between Mannheim and Foulkes (previously unpublished). It is argued that there is close conjunction between Mannheim’s and Foulkes’s revision of clinical psychoanalysis along sociological lines. Current renderings of the Frankfurt School tradition pay almost exclusive attention to the American connection (Herbert Marcuse, Eric Fromm, Theodor Adorno and Max Horkheimer) overlooking the contribution of the English connection through the work of Mannheim and Foulkes

    Perceived barriers to pediatrician and family practitioner participation in pediatric clinical trials: Findings from the Clinical Trials Transformation Initiative.

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    Despite legislation to stimulate pediatric drug development through clinical trials, enrolling children in trials continues to be challenging. Non-investigator (those who have never served as a clinical trial investigator) providers are essential to recruitment of pediatric patients, but little is known regarding the specific barriers that limit pediatric providers from participating in and referring their patients to clinical trials. We conducted an online survey of pediatric providers from a wide variety of practice types across the United States to evaluate their attitudes and awareness of pediatric clinical trials. Using a 4-point Likert scale, providers described their perception of potential barriers to their practice serving as a site for pediatric clinical trials. Of the 136 providers surveyed, 52/136 (38%) had previously referred a pediatric patient to a trial, and only 17/136 (12%) had ever been an investigator for a pediatric trial. Lack of awareness of existing pediatric trials was a major barrier to patient referral by providers, in addition to consideration of trial risks, distance to the site, and time needed to discuss trial participation with parents. Overall, providers perceived greater challenges related to parental concerns and parent or child logistical barriers than study implementation and ethics or regulatory barriers as barriers to their practice serving as a trial site. Providers who had previously been an investigator for a pediatric trial were less likely to be concerned with potential barriers than non-investigators. Understanding the barriers that limit pediatric providers from collaboration or inhibit their participation is key to designing effective interventions to optimize pediatric trial participation

    Combined aerobic and resistance exercise program improves task performance in patients with heart failure

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    OBJECTIVES: To assess the effects of a home-based aerobic and resistance training program on the physical function of adults with New York Heart Association (NYHA) class II and III patients and systolic heart failure (HF). DESIGN: Randomized controlled trial. SETTING: Home based. PARTICIPANTS: Stable patients (N=24; mean age, 60±10y; left ventricular ejection fraction, 25%±9%; 50% white; 50% women) with New York Heart Association (NYHA) classes II and III (NYHA class III, 58%) systolic heart failure (HF). INTERVENTION: A 12-week progressive home-based program of moderate-intensity aerobic and resistance exercise. Attention control wait list participants performed light stretching and flexibility exercises. MAIN OUTCOME MEASURES: A 10-item performance-based physical function measure, the Continuous Scale Physical Functional Performance test (CS-PFP10), was the major outcome variable and included specific physical activities measured in time to complete a task, weight carried during a task, and distance walked. Other measures included muscle strength, HRQOL (Minnesota Living With Heart Failure Questionnaire, Epworth Sleepiness Scale), functional capacity (Duke Activity Status Index), and disease severity (brain natriuretic peptide) levels. RESULTS: After the exercise intervention, 9 of 10 specific task activities were performed more rapidly, with increased weight carried by exercise participants compared with the attention control wait list group. Exercise participants also showed significant improvements in CS-PFP10 total score (P<.025), upper and lower muscle strength, and HRQOL (P<.001) compared with the attention control wait list group. Adherence rates were 83% and 99% for the aerobic and resistance training, respectively. CONCLUSIONS: Patients with stable HF who participate in a moderate-intensity combined aerobic and resistance exercise program may improve performance of routine physical activities of daily living by using a home-based exercise approach. Performance-based measures such as the CS-PFP10 may provide additional insights into physical function in patients with HF that more commonly used exercise tests may not identify. Early detection of subtle changes that may signal declining physical function that are amenable to intervention potentially may slow further loss of function in this patient population

    Analysis of the Factors that Limit the Ability of Feeder Cells to Maintain the Undifferentiated State of Human Embryonic Stem Cells

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    Human embryonic stem cell (hESC) culture is routinely performed using inactivated mouse embryonic fibroblasts (MEFs) as a feeder cell layer (FL). Although these cells maintain pluripotency of hESCs, the molecular basis for this is unknown. Objectives of this study were to determine whether timing between MEF inactivation and their use as a FL influenced hESC growth and differentiation, and to begin defining the mechanism(s) involved. hESCs were plated on MEFs prepared 1 (MEF-1), 4 (MEF-4), and 7 (MEF-7) days earlier. hESC colony morphology and Oct3/4 expression levels were evaluated to determine the influence of different FLs. Significant enhancement of hESC growth (self-renewal) was observed on MEF-1 compared with MEF-4 and/or MEF-7. Conditioned media (CM) collected from MEF-1 supported significantly better hESC growth in a FL-free system compared to MEF-7 CM. Effects of MEFs on hESC growth were not caused by differences in cell density or viability, although indications of apoptosis were observed in MEF-7. Scanning electron microscopy demonstrated that MEF-7 were morphologically distinct from MEF-1 and MEF-4. Microarray analysis identified 19 genes related to apoptosis with significantly different levels of expression between MEF-1 and MEF-7. Several differentially expressed RNAs had gene ontology classifications associated with extracellular matrix (ECM) structural constituents and growth factors. Because members of Wnt signaling pathway were identified in the array analysis, we examined the ability of the Wnt1 CM and secreted frizzled-related proteins to affect hESC growth and differentiation. The addition of Wnt1 CM to both MEF-1 and MEF-7 significantly increased the number of undifferentiated colonies, while the addition of Sfrps promoted differentiation. Together, these results suggest that microenvironment, ECM, and soluble factors expressed by MEF-1 are significantly better at maintaining self-renewal and pluripotency of hESCs. Our findings have important implications in the optimization of hESC culture when MEFs are used as FL or CM is used in FL-free culture.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/78130/1/scd.2008.0010.pd
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