2,946 research outputs found
Biogeography of American Northwest Hot Spring A/B′-Lineage Synechococcus Populations
© Copyright © 2020 Becraft, Wood, Cohan and Ward. Previous analyses have shown how diversity among unicellular cyanobacteria inhabiting island-like hot springs is structured relative to physical separation and physiochemical differences among springs, especially at local to regional scales. However, these studies have been limited by the low resolution provided by the molecular markers surveyed. We analyzed large datasets obtained by high-throughput sequencing of a segment of the photosynthesis gene psaA from samples collected in hot springs from geothermal basins in Yellowstone National Park, Montana, and Oregon, all known from previous studies to contain populations of A/B′-lineage Synechococcus. The fraction of identical sequences was greater among springs separated by 50 km, and springs separated by \u3e800 km shared sequence variants only rarely. Phylogenetic analyses provided evidence for endemic lineages that could be related to geographic isolation and/or geochemical differences on regional scales. Ecotype Simulation 2 was used to predict putative ecotypes (ecologically distinct populations), and their membership, and canonical correspondence analysis was used to examine the geographical and geochemical bases for variation in their distribution. Across the range of Oregon and Yellowstone, geographical separation explained the largest percentage of the differences in distribution of ecotypes (9.5% correlated to longitude; 9.4% to latitude), with geochemical differences explaining the largest percentage of the remaining differences in distribution (7.4–9.3% correlated to magnesium, sulfate, and sulfide). Among samples within the Greater Yellowstone Ecosystem, geochemical differences significantly explained the distribution of ecotypes (6.5–9.3% correlated to magnesium, boron, sulfate, silicon dioxide, chloride, and pH). Nevertheless, differences in the abundance and membership of ecotypes in Yellowstone springs with similar chemistry suggested that allopatry may be involved even at local scales. Synechococcus populations have diverged both by physical isolation and physiochemical differences, and populations on surprisingly local scales have been evolving independently
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Characterization of a continuous feline mammary epithelial cell line susceptible to feline epitheliotropic viruses.
Mucosal epithelial cells are the primary targets for many common viral pathogens of cats. Viral infection of epithelia can damage or disrupt the epithelial barrier that protects underlying tissues. In vitro cell culture systems are an effective means to study how viruses infect and disrupt epithelial barriers, however no true continuous or immortalized feline epithelial cell culture lines are available. A continuous cell culture of feline mammary epithelial cells (FMEC UCD-04-2) that forms tight junctions with high transepithelial electrical resistance (>2000Omegacm(-1)) 3-4 days after reaching confluence was characterized. In addition, it was shown that FMECs are susceptible to infection with feline calicivirus (FCV), feline herpesvirus (FHV-1), feline coronavirus (FeCoV), and feline panleukopenia virus (FPV). These cells will be useful for studies of feline viral disease and for in vitro studies of feline epithelia
A portable neutron spectroscope (NSPECT) for detection, imaging and identification of nuclear material
We have developed, fabricated and tested a prototype imaging neutron spectrometer designed for real-time neutron source location and identification. Real-time detection and identification is important for locating materials. These materials, specifically uranium and transuranics, emit neutrons via spontaneous or induced fission. Unlike other forms of radiation (e.g. gamma rays), penetrating neutron emission is very uncommon. The instrument detects these neutrons, constructs images of the emission pattern, and reports the neutron spectrum. The device will be useful for security and proliferation deterrence, as well as for nuclear waste characterization and monitoring. The instrument is optimized for imaging and spectroscopy in the 1-20 MeV range. The detection principle is based upon multiple elastic neutron-proton scatters in organic scintillator. Two detector panel layers are utilized. By measuring the recoil proton and scattered neutron locations and energies, the direction and energy spectrum of the incident neutrons can be determined and discrete and extended sources identified. Event reconstruction yields an image of the source and its location. The hardware is low power, low mass, and rugged. Its modular design allows the user to combine multiple units for increased sensitivity. We will report the results of laboratory testing of the instrument, including exposure to a calibrated Cf-252 source. Instrument parameters include energy and angular resolution, gamma rejection, minimum source identification distances and times, and projected effective area for a fully populated instrument
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Visualisation of Origins, Destinations and Flows with OD Maps
We present a new technique for the visual exploration of origins (O) and destinations (D) arranged in geographic space. Previous attempts to map the flows between origins and destinations have suffered from problems of occlusion usually requiring some form of generalisation, such as aggregation or flow density estimation before they can be visualized. This can lead to loss of detail or the introduction of arbitrary artefacts in the visual representation. Here, we propose mapping OD vectors as cells rather than lines, comparable with the process of constructing OD matrices, but unlike the OD matrix, we preserve the spatial layout of all origin and destination locations by constructing a gridded two‐level spatial treemap. The result is a set of spatially ordered small multiples upon which any arbitrary geographic data may be projected. Using a hash grid spatial data structure, we explore the characteristics of the technique through a software prototype that allows interactive query and visualisation of 105‐106 simulated and recorded OD vectors. The technique is illustrated using US county to county migration and commuting statistics
Public Scholarship at Indiana University-Purdue University
Community engagement is a defining attribute of the campus, and the
current Strategic Plan identifies a number of strategic actions to “Deepen
our Commitment to Community Engagement.” In May 2015, A Faculty
Learning Community (FLC) on Public Scholarship was established in
May, 2015 to address the campus strategic goals to “recognize and reward
contributions to community engagement” and “define community
engagement work…in Faculty Annual Reports and promotion and tenure
guidelines.” At IUPUI, scholarly work occurs in research and creative
activity, teaching, and/or service. In terms of promotion and tenure, faculty
members must declare an area of excellence in one of these three domains.
The FLC on Public Scholarship is a 3-year initiative co-sponsored by
Academic Affairs and the Center for Service and Learning (CSL). Seven
faculty members from across campus were selected to be part of the
2015-2016 FLC, and two co-chairs worked closely with CSL staff to plan
and facilitate the ongoing work. The FLC is charged with defining public
scholarship, identifying criteria to evaluate this type of scholarship, assist
faculty in documenting their community-engaged work, and working with
department Chairs and Deans in adapting criteria into promotion and
tenure materials. The intended audiences for this work includes faculty,
community-engaged scholars, public scholars, promotion and tenure
committees, external reviewers, and department Chairs and Deans. The
following provides background to the campus context and a brief summary
of work to date, including definition and proposed criteria to evaluate public
scholarship.IUPUI Center for Service and Learning; IUPUI Office of Academic Affair
Alzheimer’s Prevention Initiative Generation Program: Development of an APOE genetic counseling and disclosure process in the context of clinical trials
IntroductionAs the number of Alzheimer’s disease (AD) prevention studies grows, many individuals will need to learn their genetic and/or biomarker risk for the disease to determine trial eligibility. An alternative to traditional models of genetic counseling and disclosure is needed to provide comprehensive standardized counseling and disclosure of apolipoprotein E (APOE) results efficiently, safely, and effectively in the context of AD prevention trials.MethodsA multidisciplinary Genetic Testing, Counseling, and Disclosure Committee was established and charged with operationalizing the Alzheimer’s Prevention Initiative (API) Genetic Counseling and Disclosure Process for use in the API Generation Program trials. The objective was to provide consistent information to research participants before and during the APOE counseling and disclosure session using standardized educational and session materials.ResultsThe Genetic Testing, Counseling, and Disclosure Committee created a process consisting of eight components: requirements of APOE testing and reports, psychological readiness assessment, determination of AD risk estimates, guidance for identifying providers of disclosure, predisclosure education, APOE counseling and disclosure session materials, APOE counseling and disclosure session flow, and assessing APOE disclosure impact.DiscussionThe API Genetic Counseling and Disclosure Process provides a framework for largeâ scale disclosure of APOE genotype results to study participants and serves as a model for disclosure of biomarker results. The process provides education to participants about the meaning and implication(s) of their APOE results while also incorporating a comprehensive assessment of disclosure impact. Data assessing participant safety and psychological wellâ being before and after APOE disclosure are still being collected and will be presented in a future publication.Highlightsâ ¢Participants may need to learn their risk for Alzheimer’s disease to enroll in studies.â ¢Alternatives to traditional models of apolipoprotein E counseling and disclosure are needed.â ¢An alternative process was developed by the Alzheimer’s Prevention Initiative.â ¢This process has been implemented by the Alzheimer’s Prevention Initiative Generation Program.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/153071/1/trc2jtrci201909013.pd
Orientation cues for high-flying nocturnal insect migrants: do turbulence-induced temperature and velocity fluctuations indicate the mean wind flow?
Migratory insects flying at high altitude at night often show a degree of common alignment, sometimes with quite small angular dispersions around the mean. The observed orientation directions are often close to the downwind direction and this would seemingly be adaptive in that large insects could add their self-propelled speed to the wind speed, thus maximising their displacement in a given time. There are increasing indications that high-altitude orientation may be maintained by some intrinsic property of the wind rather than by visual perception of relative ground movement. Therefore, we first examined whether migrating insects could deduce the mean wind direction from the turbulent fluctuations in temperature. Within the atmospheric boundary-layer, temperature records show characteristic ramp-cliff structures, and insects flying downwind would move through these ramps whilst those flying crosswind would not. However, analysis of vertical-looking radar data on the common orientations of nocturnally migrating insects in the UK produced no evidence that the migrants actually use temperature ramps as orientation cues. This suggests that insects rely on turbulent velocity
and acceleration cues, and refocuses attention on how these can be detected, especially as small-scale turbulence is usually held to be directionally invariant (isotropic). In the second part of the paper we present a theoretical analysis and simulations showing that velocity fluctuations and accelerations felt by an insect are predicted to be anisotropic even when the small-scale turbulence (measured at a fixed point or along the trajectory of a fluid-particle) is isotropic. Our results thus provide further evidence that insects do indeed use turbulent velocity and acceleration cues as indicators of the mean wind direction
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