12,016 research outputs found
Porous silica spheres as indoor air pollutant scavengers
Porous silica spheres were investigated for their effectiveness in removing typical indoor air pollutants, such as aromatic and carbonyl-containing volatile organic compounds (VOCs), and compared to the commercially available polymer styrene-divinylbenzene (XAD-4). The silica spheres and the XAD-4 resin were coated on denuder sampling devices and their adsorption efficiencies for volatile organic compounds evaluated using an indoor air simulation chamber. Real indoor sampling was also undertaken to evaluate the affinity of the silica adsorbents for a variety of indoor VOCs. The silica sphere adsorbents were found to have a high affinity for polar carbonyls and found to be more efficient than the XAD-4 resin at adsorbing carbonyls in an indoor environment
Area Postrema
This report contains a gene expression summary of the area postrema (AP), derived from the "Allen Brain Atlas":http://www.brain-map.org/welcome.do;jsessionid=EDE40ADC940845D169DE378ADC9B71BD (ABA) in-situ hybridization (ISH) mouse data set. The structure’s location and morphological characteristics in the mouse brain are described using the Nissl data found in the "Allen Reference Atlas":http://www.brain-map.org/mouse/atlas/coronal/legend.html. Using an established algorithm, the expression values of the AP were compared to the values of the macro/parent-structure, in this case the medulla, for the purpose of extracting regionally specific gene expression data. The highest ranking ratios were then manually curated and verified. The 50 Select Genes were compiled for expression characterization. The experimental data for each gene may be accessed via the links provided; complementary sagittal data may also be accessed using the "ABA":http://www.brain-map.org/welcome.do. Correlation between gene expression in the AP and the rest of the brain, across all genes in the coronal dataset (~4300 genes), were derived computationally and are presented below. A gene ontology table (derived from DAVID Bioinformatics Resources 2007) is also included, highlighting possible functions of these 50 Select Genes. 

Understanding why farmers change their farming practices : the role of orienting principles in technology transfer
This report presents results from a qualitative study of sheep, beef and dairy farmers in the
Temuka, Geraldine area of the South Island, New Zealand. Farmers' accounts of their farming
practices, and how they decide to adopt, or not adopt, innovations are analysed to highlight the key
orienting principles that guide their decision making. Farmers in each type of production have different
orientations to innovation, in large part reflecting the nature of the industry in which they are located.
Sheep and beef farmers emphasise profitability and the need to control risk and to farm safely. Dairy
farmers emphasise increasing production, increasing efficiency and control by monitoring production.
The results are important for alerting researchers and educationalists to the farmers' point of view in the development of effective extension.Funding for this research was received from the Foundation for Research, Science and Technology.
The Lotteries Board supported the research by providing technical equipment. The former New
Zealand Institute for Social Research and Development initiated this project and it was continued by the
AERU in November, 1994
Airborne Radar for sUAS Sense and Avoid
A primary challenge for the safe integration of small UAS operations into the National Airspace System (NAS) is traffic deconfliction, both from manned and unmanned aircraft. The UAS Traffic Management (UTM) project being conducted at the National Aeronautics and Space Administration (NASA) considers a layered approach to separation provision, ranging from segregation of operations through airspace volumes (geofences) to autonomous sense and avoid (SAA) technologies for higher risk, densely occupied airspace. Cooperative SAA systems, such as Automatic Dependent Surveillance-Broadcast (ADS-B) and/or vehicle-to-vehicle communication systems provide significant additional risk mitigation but they fail to adequately mitigate collision risks for non-cooperative (non-transponder equipped) airborne aircraft. The RAAVIN (Radar on Autonomous Aircraft to Verify ICAROUS Navigation) flight test being conducted by NASA and the Mid-Atlantic Aviation Partnership (MAAP) was designed to investigate the applicability and performance of a prototype, commercially available sUAS radar to detect and track non-cooperative airborne traffic, both manned and unmanned. The radar selected for this research was a Frequency Modulated Continuous Wave (FMCW) radar with 120 degree azimuth and 80 degree elevation field of view operating at 24.55GHz center frequency with a 200 MHz bandwidth. The radar transmits 2 watts of power thru a Metamaterial Electronically Scanning Array antenna in horizontal polarization. When the radar is transmitting, personnel must be at least 1 meter away from the active array to limit nonionizing radiation exposure. The radar physical dimensions are 18.7cm by 12.1cm by 4.1cm and it weighs less than 820 grams making it well suited for installation on small UASs. The onboard, SAA capability, known as ICAROUS, (Independent Configurable Architecture for Reliable Operations of Unmanned Systems), developed by NASA to support sUAS operations, will provide autonomous guidance using the traffic radar tracks from the onboard radar. The RAAVIN set of studies will be conducted in three phases. The first phase included outdoor, ground-based radar evaluations performed at the Virginia Techs Kentland Farm testing range in Blacksburg, VA. The test was designed to measure how well the radar could detect and track a small UAS flying in the radars field of view. The radar was used to monitor 5 test flights consisting of outbound, inbound and crossing routes at different ranges and altitudes. The UAS flown during the ground test was the Inspire 2, a quad copter weighing less than 4250 grams (10 pounds) at maximum payload. The radar was set up to scan and track targets over its full azimuthal field of view from 0 to 40 degrees in elevation. The radar was configured to eliminate tracks generated from any targets located beyond 2000 meters from the radar and moving at velocities under 1.45 meters per second. For subsequent phases of the study the radar will be integrated with a sUAS platform to evaluate its performance in flight for SAA applications ranging from sUAS to manned GA aircraft detections and tracking. Preliminary data analysis from the first outdoor ground tests showed the radar performed well at tracking the vehicle as it flew outbound and repeatedly maintained a track out to 1000 meters (maximum 1387 meters) until the vehicle slowed to a stop to reverse direction to fly inbound. As the Inspire flew inbound tracks from beyond 800 meters, a reacquisition time delay was consistently observed between when the Inspire exceeds a speed of 1.45 meters per second and when the radar indicated an inbound target was present and maintained its track. The time delay varied between 6 seconds to over 37 seconds for the inbound flights examined, and typically resulted in about a 200 meter closure distance before the Inspire track was maintained. The radar performed well at both acquiring and tracking the vehicle as it flew crossing routes out past 400 meters across the azimuthal field of view. The radar and ICAROUS software will be integrated and flown on a BFD-1400-SE8-E UAS during the next phase of the RAAVIN project. The main goal at the conclusion of this effort is to determine if this radar technology can reliably support minimum requirements for SAA applications of sUAS. In particular, the study will measure the range of vehicle detections, lateral and vertical angular errors, false and missed/late detections, and estimated distance at closest point of approach after an avoidance maneuver is executed. This last metric is directly impacted by sensor performance and indicates its suitability for the task
Stepped vitrification technique for human ovarian tissue cryopreservation
The advantage of stepped vitrification (SV) is avoiding ice crystal nucleation, while decreasing the toxic effects of high cryoprotectant concentrations. We aimed to test this method for human ovarian tissue cryopreservation. Ovarian cortex was taken from 7 fertile adult women. Samples were subjected to an SV protocol performed in an automatic freezer, which allowed sample transfer to ever higher concentrations of dimethyl sulfoxide (DMSO) as the temperature was reduced. Histological evaluation of the vitrified-warmed tissue showed large numbers of degenerated follicles after 24 hours of in vitro culture. We therefore evaluated DMSO perfusion rates by X-ray computed tomography, ice crystal formation by freeze-substitution, and cell toxicity by transmission electron microscopy, seeking possible reasons why follicles degenerated. Although cryoprotectant perfusion was considered normal and no ice crystals were formed in the tissue, ultrastructural analysis detected typical signs of DMSO toxicity, such as mitochondria degeneration, alterations in chromatin condensation, cell vacuolization and extracellular matrix swelling in both stromal and follicular cells. The findings indicated that the method failed to preserve follicles due to the high concentrations of DMSO used. However, adaptations can be made to avoid toxicity to follicles caused by elevated levels of cryoprotectants.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) 2016/22947-
Toward a Theory of Legislative Decision
Recent developments in formal political analysis have spawned two seemingly related theories of democratic political processes. The more familiar of the two is the theory of electoral competition based on Downs' (1957) heuristics and greatly elaborated by Davis, Hinich and Ordeshook (1970), Kramer (1975), McKelvey (1976), and others. Somewhat less familiar (perhaps because the intellectual movement is less well integrated) is the theory of legislative decision which has grown from roots in game theory and the theory of social choice. Black (1958), Riker (1962), Plott (1967), Wilson (1969), Schwartz (1970), Kadane (1972), and several others have nurtured the rudimentary models which compose this theory
The Images of Incumbents in Great Britain and the United States
Incumbents in single member, simple plurality systems strive to develop name recognition and positive images of themselves. We propose to analyze the images that constituents in Great Britain and the United States have of their MPs and Congressmen and to measure the impact which incumbent activities have on those images. We also examine the normative expectations that constituents in both countries have of their representatives and how these expectations shape their evaluations.
The data for this study comes from matching elite and voter surveys in Great Britain and the United States. Our results can be summarized as follows: 1) a large percentage of constituents in both countries believe that casework and protecting district interests are the most important functions of the representative; 2) those from working class, less well educated backgrounds are more inclined to prefer a service role for their representative than a policy role; 3) the evaluations that constituents have of their representatives reflects the importance of constituency service in their priorities as well; and 4) that representatives who undertake high levels of constituency service have better constituent images than other representatives
The Constituency Service Basis of the Personal Vote for U.S. Representatives and British Members of Parliament
Under the guise of the "incumbency advantage" American research of the past decade has devoted heavy emphasis to what may be termed the "personal vote" in Congressional elections. Is this phenomenon a purely American one, or is it something susceptible to comparative treatment? This paper contrasts the personal vote in the 1980 U. S. House elections with that in the 1979 British General Election. The analysis utilizes data from surveys conducted by the Center for Political Studies and British Gallup, respectively, in combination with interviews of House AAs and British MPs and party agents whose constituencies fall in the sampling frames of the mass surveys. The analysis finds an incumbency advantage or personal vote in Britain, much weaker than that in the U. S., but of somewhat greater importance than is commonly believed, As in the U. S. constituency service appears to be an important component of the personal vote
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