2,134 research outputs found
A feasibility study: California Department of Forestry and Fire Protection utilization of infrared technologies for wildland fire suppression and management
NASA's JPL has completed a feasibility study using infrared technologies for wildland fire suppression and management. The study surveyed user needs, examined available technologies, matched the user needs with technologies, and defined an integrated infrared wildland fire mapping concept system configuration. System component trade-offs were presented for evaluation in the concept system configuration. The economic benefits of using infrared technologies in fire suppression and management were examined. Follow-on concept system configuration development and implementation were proposed
Transcription of Nonrepeated DNA in Neonatal and Fetal Mice
The transcription of nonrepeated DNA sequences was measured by hybridization of RNA from neonatal and fetal mice to mouse DNA using three different techniques. The measurements indicate that a large part (about 70%) of the rapidly-labeled fetal RNA is transcribed from nonrepeated DNA sequences. It appears that more than 12% of the single-copy DNA sequences are represented in the RNA of newborn mice
Distribution of 5-HT and DA receptors in primate prefrontal cortex: implications for pathophysiology and treatment
El pdf del artículo es la versión pre-print.The prefrontal cortex (PFC) has attracted a great research interest because of its involvement in the control of executive functions in both health and disease, and particularly in cognitive functions such as working memory. In schizophrenia, alterations in the PFC are documented at many different levels: molecular, cellular and functional. Furthermore, deficits in cognitive abilities are considered a core feature of schizophrenia and remain a major unmet medical need with respect to this disorder. In order to understand the sites of action of currently used drugs, as well as of the new experimental treatments being developed and acting in this brain region, it is important to have a detailed knowledge of the corresponding chemical neuroanatomy. Here we review current knowledge regarding the cellular localization of 5-HT1A, 5-HT2A and dopamine D1, D5, and D2, D4 receptors in primate PFC and their possible functions in the neuronal circuits of the PFC.J. de Almeida is the recipient of a fellowship from the Spanish Ministry of Education. This research was funded by the Fundació La Marató TV3 (#01/3930). Support from the Generalitat de Catalunya (Grup de Recerca de Qualitat 2005-SGR0758) is also acknowledged.Peer reviewe
Speed and Accuracy of Static Image Discrimination by Rats
When discriminating dynamic noisy sensory signals, human and primate subjects
achieve higher accuracy when they take more time to decide, an effect
attributed to accumulation of evidence over time to overcome neural noise. We
measured the speed and accuracy of twelve freely behaving rats discriminating
static, high contrast photographs of real-world objects for water reward in a
self-paced task. Response latency was longer in correct trials compared to
error trials. Discrimination accuracy increased with response latency over the
range of 500-1200ms. We used morphs between previously learned images to vary
the image similarity parametrically, and thereby modulate task difficulty from
ceiling to chance. Over this range we find that rats take more time before
responding in trials with more similar stimuli. We conclude that rats'
perceptual decisions improve with time even in the absence of temporal
information in the stimulus, and that rats modulate speed in response to
discrimination difficulty to balance speed and accuracy
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Transplantation of progenitor cells and regeneration enhancement in acute myocardial infarction - (TOPCARE-AMI)
Background - Experimental studies suggest that transplantation of blood-derived or bone marrow–derived progenitor cells beneficially affects postinfarction remodeling. The safety and feasibility of autologous progenitor cell transplantation in patients with ischemic heart disease is unknown
"It has no meaning to me". How do researchers understand the effectiveness of literature searches? A qualitative analysis and preliminary typology of understandings
This study aimed to address the question: what does “effectiveness” mean to researchers in the context of literature searching for systematic reviews?
We conducted a thematic analysis of responses to an e‐mail survey. Eighty‐nine study authors, whose studies met inclusion in a recent review (2018), were contacted via e‐mail and asked three questions; one directly asking the question: in literature searching, what does effective (or effectiveness in) literature searching mean to you?
Thirty‐eight (46%) responses were received from diverse professional groups, including: literature searchers, systematic reviewers, clinicians and researchers. A shared understanding of what effectiveness means was not identified. Instead, five themes were developed from data: 1) effectiveness is described as a metric; 2) effectiveness is a balance between metrics; 3) effectiveness can be categorised by search purpose; 4) effectiveness is an outcome; and, 5) effectiveness is an experimental concept. We propose that these themes constitute a preliminary typology of understandings.
No single definition of effectiveness was identified. The proposed typology suggests that different researchers have differing understandings of effectiveness. This could lead to uncertainty as to the aim and the purpose of literature searches and confusion about the outcomes. The typology offers a potential route for further exploration
Classical phase transitions in a one-dimensional short-range spin model
Ising's solution of a classical spin model famously demonstrated the absence
of a positive-temperature phase transition in one-dimensional equilibrium
systems with short-range interactions. No-go arguments established that the
energy cost to insert domain walls in such systems is outweighed by entropy
excess so that symmetry cannot be spontaneously broken. An archetypal way
around the no-go theorems is to augment interaction energy by increasing the
range of interaction. Here we introduce new ways around the no-go theorems by
investigating entropy depletion instead. We implement this for the Potts model
with invisible states.Because spins in such a state do not interact with their
surroundings, they contribute to the entropy but not the interaction energy of
the system. Reducing the number of invisible states to a negative value
decreases the entropy by an amount sufficient to induce a positive-temperature
classical phase transition. This approach is complementary to the long-range
interaction mechanism. Alternatively, subjecting positive numbers of invisible
states to imaginary or complex fields can trigger such a phase transition. We
also discuss potential physical realisability of such systems.Comment: 29 pages, 11 figure
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