536 research outputs found
Spatial heterodyne observations of water (SHOW) from a high-altitude airplane: characterization, performance, and first results
The Spatial Heterodyne Observations of Water instrument (SHOW) is a
limb-sounding satellite prototype that utilizes the Spatial Heterodyne
Spectroscopy (SHS) technique, operating in a limb-viewing configuration, to
observe limb-scattered sunlight in a vibrational band of water vapour within
a spectral window from 1363 to 1366 nm. The goal is to retrieve high
vertical and horizontal resolution measurements of water vapour in the upper
troposphere and lower stratosphere. The prototype instrument has been
configured for observations from NASA's ER-2 high-altitude airborne remote
science airplane. Flying at a maximum altitude of ∼21.34 km with a
maximum speed of ∼760 km h−1, the
ER-2 provides a stable platform to simulate observations from a low-earth
orbit satellite. Demonstration flights were performed from the ER-2 during an
observation campaign from 15 to 22 July 2017. In this paper, we present the
laboratory characterization work and the level 0 to level 1 processing of
flight data that were obtained during an engineering flight performed on
18 July 2017. Water vapour profile retrievals are presented and compared to
in situ radiosonde measurements made of the same approximate column of air.
These measurements are used to validate the SHOW measurement concept and
examine the sensitivity of the technique.</p
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An online study combining the constructs from the theory of planned behaviour and protection motivation theory in predicting intention to test for chlamydia in two testing contexts
Chlamydia is a common sexually-transmitted infection that has potentially serious consequences unless detected and treated early. The health service in the UK offers clinic-based testing for chlamydia but uptake is low. Identifying the predictors of testing behaviours may inform interventions to increase uptake. Self-tests for chlamydia may facilitate testing and treatment in people who avoid clinic-based testing. Self-testing and being tested by a health care professional (HCP) involve two contrasting contexts that may influence testing behaviour. However, little is known about how predictors of behaviour differ as a function of context. In this study, theoretical models of behaviour were used to assess factors that may predict intention to test in two different contexts: self-testing and being tested by a HCP. Individuals searching for, or reading about chlamydia testing online were recruited using Google Adwords. Participants completed an online questionnaire that addressed previous testing behaviour and measured constructs of the Theory of Planned Behaviour and Protection Motivation Theory, which propose a total of eight possible predictors of intention. The questionnaire was completed by 310 participants. Sufficient data for multiple regression were provided by 102 and 118 respondents for self-testing and testing by a HCP respectively. Intention to self-test was predicted by vulnerability and self-efficacy, with a trend-level effect for response efficacy. Intention to be tested by a HCP was predicted by vulnerability, attitude and subjective norm. Thus, intentions to carry out two testing behaviours with very similar goals can have different predictors depending on test context. We conclude that interventions to increase self-testing should be based on evidence specifically related to test context
Blueberry Research Progress Report
The 1976 edition of the Blueberry Research Progress Report was prepared for the Blueberry Advisory Committee by researchers at the University of Maine, Orono. Projects in this report include:
1. Effect of Plant-Water Stress on Lowbush Blueberry Growth, Yield and Quality
2. Insects Affecting the Blueberry
3. The Development of Blueberry Varieties Adapted to Maine
4. Weed Control in Blueberry Fields
5. Pruning of Blueberries
6. Integrated Management of Blueberry Fields
7. The Physiology and Biochemistry of the Development of the Lowbush Blueberry Fruit
8. Survey of Red Leaf Disease of Blueberries
9. Blossom Blight of Blueberries
10. Blueberry Marketing and Cost Analysis of Producing Blueberries
11. Factors Regulating Rhizome Initiation and Development in the Lowbush Blueberry
12. New Food Products and Servic
Blueberry Research Progress Report
The 1975 edition of the Blueberry Research Progress Report was prepared for the Blueberry Advisory Committee by researchers at the University of Maine, Orono. Projects in this report include:
1. Insects Affecting the Blueberry
2. Weed Control in Blueberry Fields
3. Pruning of Blueberries
4. Integrated Management of Blueberry Fields
5. Selective Thinning of Black Barrenberries in Lowbush Blueberry Fields with Ethrel
6. The Physiology and Biochemistry of the Development of the Lowbush Blueberry Fruit
7. The Development of Blueberry Varieties Adapted to Maine
8. Factors Regulating Rhizome Initiation and Development in the Lowbush Blueberry
9. Mechanical Blueberry Harvesting
10. Blueberry Marketing and Cost Analysis of Producing Blueberries
11. New Food Products and Servic
Blueberry Progress Reports
The 1978 edition of the Blueberry Progress Reports was prepared for the Maine Blueberry Commission and the University of Maine Blueberry Advisory Committee by researchers with the Maine Life Sciences and Agriculture Experiment Station and Maine Cooperative Extension Service at the University of Maine, Orono. Projects in this report include:
1. Weed Control in Blueberry Fields
2. Pruning of Blueberries
3. Integrated Management of Blueberry Fields
4. Factors Regulating Rhizome Initiation and Development in the Lowbush Blueberry
5. Effect of Plant-Water Stress on Lowbush Blueberry Growth Yield and Quality
6. Blossom Blight of Blueberries
7. Botrytis Blossom Blight of Lowbush Blueberries
8. Insects Affecting the Blueberry
9. Treatment of Blueberries with Potassium Sorbate to Reduce Spoilage During Temporary Storage
10. Cooperative Extension Activitie
BioTorrents: A File Sharing Service for Scientific Data
The transfer of scientific data has emerged as a significant challenge, as datasets continue to grow in size and demand for open access sharing increases. Current methods for file transfer do not scale well for large files and can cause long transfer times. In this study we present BioTorrents, a website that allows open access sharing of scientific data and uses the popular BitTorrent peer-to-peer file sharing technology. BioTorrents allows files to be transferred rapidly due to the sharing of bandwidth across multiple institutions and provides more reliable file transfers due to the built-in error checking of the file sharing technology. BioTorrents contains multiple features, including keyword searching, category browsing, RSS feeds, torrent comments, and a discussion forum. BioTorrents is available at http://www.biotorrents.net
Proteorhodopsin Phototrophy Promotes Survival of Marine Bacteria during Starvation
Mutational analysis provides direct evidence for the link between proteorhodopsin light-harvesting and enhanced survival of marine bacteria
Sequence of the hyperplastic genome of the naturally competent Thermus scotoductus SA-01
<p>Abstract</p> <p>Background</p> <p>Many strains of <it>Thermus </it>have been isolated from hot environments around the world. <it>Thermus scotoductus </it>SA-01 was isolated from fissure water collected 3.2 km below surface in a South African gold mine. The isolate is capable of dissimilatory iron reduction, growth with oxygen and nitrate as terminal electron acceptors and the ability to reduce a variety of metal ions, including gold, chromate and uranium, was demonstrated. The genomes from two different <it>Thermus thermophilus </it>strains have been completed. This paper represents the completed genome from a second <it>Thermus </it>species - <it>T. scotoductus</it>.</p> <p>Results</p> <p>The genome of <it>Thermus scotoductus </it>SA-01 consists of a chromosome of 2,346,803 bp and a small plasmid which, together are about 11% larger than the <it>Thermus thermophilus </it>genomes. The <it>T. thermophilus </it>megaplasmid genes are part of the <it>T. scotoductus </it>chromosome and extensive rearrangement, deletion of nonessential genes and acquisition of gene islands have occurred, leading to a loss of synteny between the chromosomes of <it>T. scotoductus and T. thermophilus</it>. At least nine large inserts of which seven were identified as alien, were found, the most remarkable being a denitrification cluster and two operons relating to the metabolism of phenolics which appear to have been acquired from <it>Meiothermus ruber</it>. The majority of acquired genes are from closely related species of the Deinococcus-Thermus group, and many of the remaining genes are from microorganisms with a thermophilic or hyperthermophilic lifestyle. The natural competence of <it>Thermus scotoductus </it>was confirmed experimentally as expected as most of the proteins of the natural transformation system of <it>Thermus thermophilus </it>are present. Analysis of the metabolic capabilities revealed an extensive energy metabolism with many aerobic and anaerobic respiratory options. An abundance of sensor histidine kinases, response regulators and transporters for a wide variety of compounds are indicative of an oligotrophic lifestyle.</p> <p>Conclusions</p> <p>The genome of <it>Thermus scotoductus </it>SA-01 shows remarkable plasticity with the loss, acquisition and rearrangement of large portions of its genome compared to <it>Thermus thermophilus</it>. Its ability to naturally take up foreign DNA has helped it adapt rapidly to a subsurface lifestyle in the presence of a dense and diverse population which acted as source of nutrients. The genome of <it>Thermus scotoductus </it>illustrates how rapid adaptation can be achieved by a highly dynamic and plastic genome.</p
Identification of the Regulatory Logic Controlling Salmonella Pathoadaptation by the SsrA-SsrB Two-Component System
Sequence data from the past decade has laid bare the significance of horizontal gene transfer in creating genetic diversity in the bacterial world. Regulatory evolution, in which non-coding DNA is mutated to create new regulatory nodes, also contributes to this diversity to allow niche adaptation and the evolution of pathogenesis. To survive in the host environment, Salmonella enterica uses a type III secretion system and effector proteins, which are activated by the SsrA-SsrB two-component system in response to the host environment. To better understand the phenomenon of regulatory evolution in S. enterica, we defined the SsrB regulon and asked how this transcription factor interacts with the cis-regulatory region of target genes. Using ChIP-on-chip, cDNA hybridization, and comparative genomics analyses, we describe the SsrB-dependent regulon of ancestral and horizontally acquired genes. Further, we used a genetic screen and computational analyses integrating experimental data from S. enterica and sequence data from an orthologous regulatory system in the insect endosymbiont, Sodalis glossinidius, to identify the conserved yet flexible palindrome sequence that defines DNA recognition by SsrB. Mutational analysis of a representative promoter validated this palindrome as the minimal architecture needed for regulatory input by SsrB. These data provide a high-resolution map of a regulatory network and the underlying logic enabling pathogen adaptation to a host
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