191 research outputs found
Twenty Years of Undergraduate Libraries: Whence and Whither?
Undergraduate libraries as part of university library systems have existed since 1949, but there is little statistical data prior to 1971. This study examines statistics reported since that time, supplemented with electronic mail surveying, to show how such libraries have responded to the changing needs of an undergraduate population. The results show that change, and rapid response to external forces, are hallmarks of undergraduate libraries past and present
Putting aquifers into atmospheric simulation models: an example from the Mill Creek Watershed, northeastern Kansas
Aquifer–atmosphere interactions can be important in regions where the water table is shallow (\u3c2 m). A shallow water table provides moisture for the soil and vegetation and thus acts as a source term for evapotranspiration to the atmosphere. A coupled aquifer–land surface–atmosphere model has been developed to study aquifer–atmosphere interactions in watersheds, on decadal timescales. A single column vertically discretized atmospheric model is linked to a distributed soil-vegetation–aquifer model. This physically based model was able to reproduce monthly and yearly trends in precipitation, stream discharge, and evapotranspiration, for a catchment in northeastern Kansas. However, the calculated soil moisture tended to drop to levels lower than were observed in drier years. The evapotranspiration varies spatially and seasonally and was highest in cells situated in topographic depressions where the water table is in the root zone. Annually, simulation results indicate that from 5–20% of groundwater supported evapotranspiration is drawn from the aquifer. The groundwater supported fraction of evapotranspiration is higher in drier years, when evapotranspiration exceeds precipitation. A long-term (40 year) simulation of extended drought conditions indicated that water table position is a function of groundwater hydrodynamics and cannot be predicted solely on the basis of topography. The response time of the aquifer to drought conditions was on the order of 200 years indicating that feedbacks between these two water reservoirs act on disparate time scales. With recent advances in the computational power of massively parallel supercomputers, it may soon become possible to incorporate physically based representations of aquifer hydrodynamics into general circulation models (GCM) land surface parameterization schemes
Toward an Age-Friendly Portland
Toward an Age-Friendly Portland connects the people-friendly efforts of the Portland Plan with input and specific needs expressed by older Portlanders to create a vision for what people want their neighborhoods to be like as they grow older. This vision informs recommendations that may be integrated into Portland’s planning efforts. Orca Planning found that the needs of older adults now and in the future are not adequately met by the transportation, housing and greenspace options available in today’s Portland. This project was conducted under the supervision of Ethan Seltzer and Gil Kelley
The Mission Accessible Near-Earth Objects Survey: Four years of photometry
Over 4.5 years, the Mission Accessible Near-Earth Object Survey (MANOS)
assembled 228 Near-Earth Object (NEO) lightcurves. We report rotational
lightcurves for 82 NEOs, constraints on amplitudes and periods for 21 NEOs,
lightcurves with no detected variability within the image signal to noise and
length of our observing block for 30 NEOs, and 10 tumblers. We uncovered 2
ultra-rapid rotators with periods below 20s; 2016MA with a potential rotational
periodicity of 18.4s, and 2017QG rotating in 11.9s, and estimate the
fraction of fast/ultra-rapid rotators undetected in our project plus the
percentage of NEOs with a moderate/long periodicity undetectable during our
typical observing blocks. We summarize the findings of a simple model of
synthetic NEOs to infer the object morphologies distribution using the measured
distribution of lightcurve amplitudes. This model suggests a uniform
distribution of axis ratio can reproduce the observed sample. This suggests
that the quantity of spherical NEOs (e.g., Bennu) is almost equivalent to the
quantity of highly elongated objects (e.g., Itokawa), a result that can be
directly tested thanks to shape models from Doppler delay radar imaging
analysis. Finally, we fully characterized 2 NEOs as appropriate targets for a
potential robotic/human mission: 2013YS and 2014FA due to their
moderate spin periods and low .Comment: Accepted for Publication, The Astrophysical Journal Supplement Serie
Material Around the Centaur (2060) Chiron from the 2018 November 28 UT Stellar Occultation
A stellar occultation of Gaia DR3 2646598228351156352 by the Centaur (2060)
Chiron was observed from the South African Astronomical Observatory on 2018
November 28 UT. Here we present a positive detection of material surrounding
Chiron from the 74-in telescope for this event. Additionally, a global
atmosphere is ruled out at the tens of mircobar level for several possible
atmospheric compositions. There are multiple 3-sigma drops in the 74-in light
curve: three during immersion and two during emersion. Occulting material is
located between 242-270 km from the center of the nucleus in the sky plane.
Assuming the ring-plane orientation proposed for Chiron from the 2011
occultation, the flux drops are located at 352, 344, and 316 km (immersion),
and 357, and 364 km (emersion) from the center, with normal optical depths of
0.26, 0.36, and 0.22 (immersion) and 0.26 and 0.18 (emersion), and equivalent
widths between 0.7-1.3 km. This detection is similar to the previously proposed
two-ring system and is located within the error bars of that ring-pole plane;
however, the normal optical depths are less than half of the previous values,
and three features are detected on immersion. These results suggest that the
properties of the surrounding material have evolved between the 2011, 2018, and
2022 observations.Comment: Accepted by the Planetary Science Journal 21 Oct. 2023; 13 pages, 9
figures, 4 table
cGMP Recombinant FIX for IV and Oral Hemophilia B Therapy
Three specific aims are proposed: Specific Aim # 1. Process engineer and scale-up the recovery and purification of transgenic recombinant human Factor IX. The University of Nebraska-Lincoln Biological Process Development Facility will complete process development and scale-up, and produce clinical grade materials for preclinical studies. The endpoint is a proposed final product specification to help facilitate transfer to current Good Manufacturing Practices compliant production of clinical grade material to support an Investigational New Drug filing with the United States Food and Drug Administration (FDA) leading to clinical trials. Specific Aim #2. Characterize and formulate transgenic recombinant human Factor IX for intravenous dosage, and evaluate in a hemophilia B dog model. These activities are directed toward characterization of the product important to assure the provision of safe and reproducibly effective hemostasis. The results of these investigations will help support an IND filing with the FDA. Specific Aim # 3. Develop an oral dosage form of transgenic recombinant human Factor IX, and evaluate in hemophilia B mice and dog models. Oral administration of coagulation therapy will obviate the invasiveness, discomfort, potential for opportunistic infection, and complications of storage and supplies that accompany intravenous administration. Oral dosage forms of Factor IX will thus greatly increase the proportion of the patient population that can be treated. There is also published evidence suggesting that oral administration may reduce the potential for complicating immune responses to replacement therapy, especially in patients with severe hemophilia
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