1,528 research outputs found
Observing the sky at extremely high energies with the Cherenkov Telescope Array: Status of the GCT project
The Cherenkov Telescope Array is the main global project of ground-based
gamma-ray astronomy for the coming decades. Performance will be significantly
improved relative to present instruments, allowing a new insight into the
high-energy Universe [1]. The nominal CTA southern array will include a
sub-array of seventy 4 m telescopes spread over a few square kilometers to
study the sky at extremely high energies, with the opening of a new window in
the multi-TeV energy range. The Gamma-ray Cherenkov Telescope (GCT) is one of
the proposed telescope designs for that sub-array. The GCT prototype recorded
its first Cherenkov light on sky in 2015. After an assessment phase in 2016,
new observations have been performed successfully in 2017. The GCT
collaboration plans to install its first telescopes and cameras on the CTA site
in Chile in 2018-2019 and to contribute a number of telescopes to the
subsequent CTA production phase.Comment: 8 pages, 7 figures, ICRC201
Defending America by Aiding the Allies: The British Student Pilots at Arcadia and Clewiston, 1941-1945
Monday morning, June 8, 1941, 99 British citizens arrived at the Atlantic Coast Line depot in Arcadia, Florida. Although dressed in civilian clothes, all were members of the Royal Air Force destined for training as pilots in the United States before returning to defend king and country in the raging European war. It was a delicate situation. The United States was trying to aid Britain and her allies while maintaining its official neutrality
Determining the efficacy of a biosensor to detect calpastatin, a meat tenderness indicator
The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file.Title from title screen of research.pdf file (viewed on September 18, 2007)Vita.Thesis (Ph. D.) University of Missouri-Columbia 2007.An instrumental tenderness detection system used at the time of grading to sort beef carcasses on their predicted tenderness would be valuable for the beef industry. A biosensor to accurately predict calpastatin, the inhibitor of the enzyme responsible for increased tenderness due to aging, has been investigated as a detection system. Longissimus dorsi samples from between the 12th and 13th rib of the beef carcass (n = 21 and n = 11) were extracted at 0, 24, 36 and 48 h postmortem for trial one and at 0 and 48 hr for trial two. These samples were assayed for calpastatin by traditional laboratory methods and with the developed biosensors. The biosensor used in trial one was an optical fiber and trial two was a capillary tube. Warner-Bratzler shear force was also performed on a steak from each carcass. In trial one, correlations were generated from each sampling period to determine the most closely correlated sampling times between the traditional assay and the biosensor. The highest correlations between the calpastatin and optical fiber were taken at 48 hr postmortem, suggesting that this is the best time for use of the biosensor in an online grading system. The correlation was lower for the capillary tube but there was less variation in the 0 hr capillary tube than the 0 hr precolumn and post-column optical fiber, therefore this is a more promising system. This research further advances the development of the biosensor and makes online assessment of calpastatin one step closer to reality.Includes bibliographical reference
Aberrant posterior cingulate connectivity classify first-episode schizophrenia from controls: A machine learning study
Background Posterior cingulate cortex (PCC) is a key aspect of the default mode network (DMN). Aberrant PCC functional connectivity (FC) is implicated in schizophrenia, but the potential for PCC related changes as biological classifier of schizophrenia has not yet been evaluated. Methods We conducted a data-driven approach using resting-state functional MRI data to explore differences in PCC-based region- and voxel-wise FC patterns, to distinguish between patients with first-episode schizophrenia (FES) and demographically matched healthy controls (HC). Discriminative PCC FCs were selected via false discovery rate estimation. A gradient boosting classifier was trained and validated based on 100 FES vs. 93 HC. Subsequently, classification models were tested in an independent dataset of 87 FES patients and 80 HC using resting-state data acquired on a different MRI scanner. Results Patients with FES had reduced connectivity between PCC and frontal areas, left parahippocampal regions, left anterior cingulate cortex, and right inferior parietal lobule, but hyperconnectivity with left lateral temporal regions. Predictive voxel-wise clusters were similar to region-wise selected brain areas functionally connected with PCC in relation to discriminating FES from HC subject categories. Region-wise analysis of FCs yielded a relatively high predictive level for schizophrenia, with an average accuracy of 72.28% in the independent samples, while selected voxel-wise connectivity yielded an accuracy of 68.72%. Conclusion FES exhibited a pattern of both increased and decreased PCC-based connectivity, but was related to predominant hypoconnectivity between PCC and brain areas associated with DMN, that may be a useful differential feature revealing underpinnings of neuropathophysiology for schizophrenia
Modeling of Charge Transfer Inefficiency in a CCD with High Speed Column Parallel Readout
Charge Coupled Devices (CCDs) have been successfully used in several high
energy physics experiments over the past two decades. Their high spatial
resolution and thin sensitive layers make them an excellent tool for studying
short-lived particles. The Linear Collider Flavour Identification (LCFI)
collaboration is developing Column-Parallel CCDs (CPCCDs) for the vertex
detector of a future Linear Collider. The CPCCDs can be read out many times
faster than standard CCDs, significantly increasing their operating speed. An
Analytic Model has been developed for the determination of the charge transfer
inefficiency (CTI) of a CPCCD. The CTI values determined with the Analytic
Model agree largely with those from a full TCAD simulation. The Analytic Model
allows efficient study of the variation of the CTI on parameters like readout
frequency, operating temperature and occupancy.Comment: 5 pages, 13 figures, presented on behalf of the LCFI Collaboration,
proceedings IEEE 2008 Nuclear Science Symposium, Dresden, Germany, and 11th
Topical Seminar on Innovative Particle and Radiation Detectors (IPRD08) 2008,
Siena, Ital
Neural Connectivity Underlying Reward and Emotion-Related Processing : Evidence From a Large-Scale Network Analysis
This work was supported by grants from the Economic and Social Research Council (ES/K013424/1) and the Leverhulme Trust (RPG-2019-010).Peer reviewedPublisher PD
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