2,728 research outputs found
Long Term Tropospheric and Stratospheric Measurements Using High Altitude Balloons
The Arkansas BalloonSAT program is an educational outreach and research program at Arkansas State University. A variety of instruments including HOBO data loggers, Anasonde, and Arduino methane sensors have been flown on flights in the past five years. Measurements using BalloonSAT provides a cost effective option, while also matching measurements made with satellites and unmanned aerial vehicles. This includes identifying water vapor, pressure, background radiation, methane, carbon dioxide and temperature profiles over seasons and years. Water vapor trends were observed to vary with seasons, with water vapor lowest in the summer and greatest in the spring at stratospheric altitudes. Methane and carbon dioxide were observed to decrease with higher altitudes because of the greater distance from emission sources. Temperature measurements followed typical atmospheric profile measurements with an inversion at the stratosphere
Balloon-borne methane and radiation measurements
The BalloonSAT program is a high altitude research and education outreach program at Arkansas State University. Weather balloons carried a Geiger counter that measured X-ray, β, and γ radiation profiles together and a methane sensor (Arduino and MQ-6 detector) in payload boxes to 30 km (90,000 ft) over the past five years. Payload boxes were foam containers for water resistant and floating abilities in possible water landings, no modifications beyond securing sensors to the payload box were made. Methane and radiation measurements are not directly related, but collected independently and flown on many flights together and therefore presented together. A radiation peak related to decreasing cosmic radiation and increased secondary radiation, or Pfotzer maximum at 10-15 km was found. Lower tropopause temperatures were related to higher radiation counts at the Pfotzer maximum. Methane is 30 times more potent as a greenhouse gas than carbon dioxide. A linear calibration curve was made with known concentrations of methane at various temperatures to convert voltage readings into concentrations. The low temperatures and pressure were not found to significantly impact concentration measurements. Methane concentration was found to decrease with altitude similar to satellite and Unmanned Aerial Vehicle (UAV) measurements. BalloonSAT does not collect data that can replace satellites, but proves to be an effective instrument in identifying radiation and methane profiles in the troposphere and lower stratosphere comparable to other balloon-borne, UAV and satellite studies
Biophysical Analysis of Nucleic Acids
This overview unit provides a thorough overview of biophysical methods used for structure analysis, including X‐ray diffraction, nuclear magnetic resonance, optical spectroscopy, theoretical and computational methods, and single‐molecule methods. Advantages and disadvantages of the methods are compared.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/143731/1/cpnc0701.pd
An effective strategy to diagnose HIV infection: findings from a national audit of HIV partner notification outcomes in sexual health and infectious disease clinics in the UK
NASA GIBS and Worldview: Visualizing NASA's Earth Science Data for All to Explore
For more than 20 years, the NASA Earth Observing System (EOS) has operated dozens of remote sensing satellites collecting nearly 15 Petabytes of data that span thousands of science parameters. Within these observations are keys the Earth Scientists have used to unlock many discoveries that we now understand about our planet. Also contained within these observations are a myriad of opportunities for learning and education. The challenge is making them accessible to educators and students in intuitive and simple ways so that effort can be spent on lesson enrichment and not overcoming technical hurdles.The NASA Global Imagery Browse Services (GIBS) system and NASA Worldview interactive mapping site provide a unique view into EOS data through daily full resolution visualizations of hundreds of Earth science parameters. For many of these parameters, visualizations are available within hours of acquisition from the satellite. For others, visualizations are available for the entire mission of the satellite. Accompanying the visualizations are visual aids such as color legends, place names, and orbit tracks. By using these visualizations, educators and students can observe natural phenomena that enrich a scientific education.This presentation will provide an overview of the visualizations available in NASA GIBS and Worldview and how they are accessed. Specific attention will be given to the newer capabilities and accomplishments, including: Support for geostationary sub-daily visualizations, Enhanced support for vector-based visualizations, Improved Worldview tour and snapshot capabilities, New imagery products across a growing set of scientific areas
Building a healthy mouse model ecosystem to interrogate cancer biology
In a recent study, Sargent et al. characterise several novel Rag1−/− mouse strains and demonstrate that genetic background strongly influences xenograft development and phenotype. Here, we discuss this work within the broader context of cancer mouse modelling. We argue that new technologies will enable insights into how specific models align with human disease states and that this knowledge can be used to develop a diverse ecosystem of complementary mouse models of cancer. By utilising these diverse, well-characterised models to provide multiple perspectives on specific cancers, it should be possible to reduce the inappropriate attrition of sound hypotheses while protecting against false positives. Furthermore, careful re-introduction of biological variation, be that through outbred populations, environmental diversity or including animals of both sexes, can ensure that results are more broadly applicable and are less impacted by particular traits of homogeneous experimental populations. Thus, careful characterisation and judicious use of an array of mouse models provides an opportunity to address some of the issues surrounding both the reproducibility and translatability crises often referenced in pre-clinical cancer research
Observing the 2017 Total Solar Eclipse in the skies above Central Missouri, USA
We report the work and findings of Arkansas BalloonSAT in participating in the 2017 Eclipse Ballooning Project. Arkansas BalloonSAT was the site-team for Missouri and launched a high altitude balloon from Fulton High School in Fulton, MO an hour prior to totality. This balloon reached an apogee of 24 kilometers shortly after floating for one minute in the moon\u27s umbra. In addition to live-streaming video from one payload as part of the Eclipse Ballooning Project, our mission included carrying a scientific payload and educational outreach. This report will summarize those efforts and include an examination of balloon kinematics with the cooling effect of the moon\u27s umbra and aircraft-balloon interaction. We further discuss developments in the system to minimize payload size for future eclipse studies
Analysis of Ultrasonic Backscatter for Porosity Characterization in Graphite-Epoxy Composites
This paper summarizes recent work on the use of ultrasonic back-scatter for the estimation of porosity levels in continuous-fiber-reinforced, layered graphite-epoxy composites. This work is a continuation of previous work described in Refs. 1–3, which addresses the effect of porosity on (1) azimuthal angle backscatter scans, and (2) the spectral characteristics of backscatter
The molecular dimension of microbial species: 1. Ecological distinctions among, and homogeneity within, putative ecotypes of Synechococcus inhabiting the cyanobacterial mat of Mushroom Spring, Yellowstone National Park
© 2015 Becraft, Wood, Rusch, Kühl, Jensen, Bryant, Roberts, Cohan and Ward. Based on the Stable Ecotype Model, evolution leads to the divergence of ecologically distinct populations (e.g., with different niches and/or behaviors) of ecologically interchangeable membership. In this study, pyrosequencing was used to provide deep sequence coverage of Synechococcus psaA genes and transcripts over a large number of habitat types in the Mushroom Spring microbial mat. Putative ecological species (putative ecotypes), which were predicted by an evolutionary simulation based on the Stable Ecotype Model (Ecotype Simulation), exhibited distinct distributions relative to temperature-defined positions in the effluent channel and vertical position in the upper 1 mm-thick mat layer. Importantly, in most cases variants predicted to belong to the same putative ecotype formed unique clusters relative to temperature and depth in the mat in canonical correspondence analysis, supporting the hypothesis that while the putative ecotypes are ecologically distinct, the members of each ecotype are ecologically homogeneous. Putative ecotypes responded differently to experimental perturbations of temperature and light, but the genetic variation within each putative ecotype was maintained as the relative abundances of putative ecotypes changed, further indicating that each population responded as a set of ecologically interchangeable individuals. Compared to putative ecotypes that predominate deeper within the mat photic zone, the timing of transcript abundances for selected genes differed for putative ecotypes that predominate in microenvironments closer to upper surface of the mat with spatiotemporal differences in light and O2 concentration. All of these findings are consistent with the hypotheses that Synechococcus species in hot spring mats are sets of ecologically interchangeable individuals that are differently adapted, that these adaptations control their distributions, and that the resulting distributions constrain the activities of the species in space and time
Effusive eruption modelling project: assessing UK impacts of trace species and sulphur deposition
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