Melanie Ailin Basnak, Veronica Perez-Schuster, Gabriela Hermitte, and Martin Beron de AstradaMany animal species take advantage of polarization vision for vital tasks such as orientation, communication, and contrast enhancement. Previous studies have …
Posts Tagged ‘polarized’
Polarized object detection in crabs: a two-channel system [RESEARCH ARTICLE]
Posted by Basnak, M. A., Perez-Schuster, V., Hermitte, G., de Astrada, M. B. on April 12th, 2018
Posted in Biology, Science General 
Tags: and horizontal orientations, Animals, Background, changes, channel, contrast, contrast enhancement, contrast sensitivity, detection, Enhancement, escape, escape response, horizontal, horizontal orientations, motion, object, Object Detection, obtained, Orientations, Polarization, Polarization Contrast, polarization contrast sensitivity, polarization vision, polarized, polarized object, polarized object detection, response, results, sensitivity, Stimulus, system, the polarization contrast, Vectors, vertical, vision 
No Comments »A method for imaging and spectroscopy using γ-rays and magnetic resonance
Posted by Yuan Zheng on September 28th, 2016
Magnetic resonance imaging (MRI) provides fine spatial resolution, spectral sensitivity and a rich variety of contrast mechanisms for diagnostic medical applications. Nuclear imaging using γ-ray cameras offers the benefits of using small quantities of radioactive tracers that seek specific targets of interest within the body. Here we describe an imaging and spectroscopic modality that combines favourable aspects of both approaches. Spatial information is encoded into the spin orientations of tiny amounts of a polarized radioactive tracer using pulses of both radio-frequency electromagnetic radiation and magnetic-field gradients, as in MRI. However, rather than detecting weak radio-frequency signals, imaging information is obtained through the detection of γ-rays. A single γ-ray detector can be used to acquire an image; no γ-ray camera is needed. We demonstrate the feasibility of our technique by producing images and spectra from a glass cell containing only about 4 × 1013 atoms (about 1 millicurie) of the metastable isomer 131mXe that were polarized using the laser technique of spin-exchange optical pumping. If the cell had instead been filled with water and imaged using conventional MRI, then it would have contained more than 1024 water molecules. The high sensitivity of our modality expands the breadth of applications of magnetic resonance, and could lead to a new class of radioactive tracers.
Posted in Biology Tags: Applications, frequency, imaging, information, magnetic, Magnetic Resonance, Modality, polarized, Radio Frequency, radioactive, Radioactive Tracers, Resonance, sensitivity, spatial, technique, Tracers No Comments »Archived Webinar: Elections in America
Posted by Social Science Space on August 29th, 2016
What is the future of American political parties as we known them? Do Americans even care about the candidates’ positions? Do campaign visits and television ads really turn the dial in voting. Political scientists Larry Bartels, Lynn Vavreck and Gary Jacobsen — address these and other questions about the current presidential election in this archived webinar.
Posted in Science General Tags: Academy, accomplish, across, actually, Address, affecting, america, american, American Academy, and social science, Annals, archived, archived webinar, Bartels, between trump, branches, called, campaign, candidates, clinton, clinton larry, clinton larry bartels, Coalition, country, deep seated persistent, Democracy, details, Disparities, disparities between, disparities between trump, divide, divided, don’t think, effect, election, Elections, electoral, Electorate, Engagement, especially, especially because, evangelical, example, getting, Government, Groups, identification, ideological, ideological disparities, ideological disparities between, Immigration, important, include, including, issues, Jacobsen, Jacobson, larry bartels, outcome, Panelists, parties, party identification, People, perhaps, persistent, persistent divide, polarized, policy, political, Political Science, Politics, Populist, positions, predict, president, presidential, Primaries, professor, Promises, Public, Public Policy, question, questions, racial, recent, Republican, Republican Party, result, results, Scholarship, Science, seated, seated persistent, seated persistent divide, september, similar, simply, Social, Social Science, states, strain, Support, support across, supporters, supreme, Supreme Court, system, the american academy, the ideological disparities, the republican party, the united states, things, trump’s, typical, United, United States, university, Unrest, vavreck, voters, Webinar, weighting, worked No Comments »Did Einstein predict Quantum Entanglement in 1905?
Posted by theimagi on August 14th, 2016
Quantum entanglement is defined "as a physical phenomenon that occurs when pairs or groups of particles are generated or interact in ways such that the quantum state of each particle cannot be described independently instead, a quantum state may be given for the system as a whole. Einstein referred to this as "spooky action at […]
Posted in Physics, Physics & Chemistry, Science General Tags: according, action, Allen Aspect, allow quantum, allow quantum mechanics, are spacelike separated, argument, aspect, cannot, cannot communicate, chronicles, communicate, complete, Complete Theory, defined, definite, distance, distance between, distance separating, eigenstates, Einstein, Entanglement, equation, example, function, hidden, hidden variable, hidden variable that, Imagineer, imagineer’s, imagineer’s chronicles, Inequities, Inequity, influence, Interact, Interaction, Limited, limited influence, making, matter, Measurement, Measurements, Mechanics, Momentum, momentum eigenstates, Moving, multiple, multiple momentum, multiple momentum eigenstates, Nature, objects, observed, Observer, Observers, other words, paperback, Particle, Particles, Perception, Perspective, Photons, physical, Physical Reality, points, polarized, polarized photons, predict, Quantum, Quantum Entanglement, Quantum Mechanics, Quantum State, reality, relative, relativistic, Relativity, Respect, separability, separability because, separated, separating, showed, slower, space time universe, spacelike, spacelike separated, spacelike separated when, spooky, Superposition, system, systems, that would allow, the distance between, the imagineer& 8217, the imagineer’s chronicles, the measurements made, the physical reality, the wave function, theory, Traveling, trying, Universe, variable, variable that would, Velocity, viewed, violated, would allow, would allow quantum No Comments »Nanometer-scale Defect Detection Using Polarized Light
Posted by Pierre Richard Dahoo, Philippe Pougnet, Abdelkhalak El Hami on August 12th, 2016
This book describes experimental and theoretical methods that are implemented within the framework of fundamental research to better understand physical and chemical processes at the nanoscale that are responsible for the remarkable prop…
