1,285 research outputs found

    Coding of stereoscopic depth information in visual areas V3 and V3A

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    The process of stereoscopic depth perception is thought to begin with the analysis of absolute binocular disparity, the difference in position of corresponding features in the left and right eye images with respect to the points of fixation. Our sensitivity to depth, however, is greater when depth judgments are based on relative disparity, the difference between two absolute disparities, compared to when they are based on absolute disparity. Therefore, the visual system is thought to compute relative disparities for fine depth discrimination. Functional magnetic resonance imaging studies in humans and monkeys have suggested that visual areas V3 and V3A may be specialized for stereoscopic depth processing based on relative disparities. In this study, we measured absolute and relative disparity tuning of neurons in V3 and V3A of alert fixating monkeys and we compared their basic tuning properties with those published previously for other visual areas. We found that neurons in V3 and V3A predominantly encode absolute, not relative, disparities. We also found that basic parameters of disparity tuning in V3 and V3A are similar to those from other extrastriate visual areas. Finally, by comparing single-unit activity with multi-unit activity measured at the same recording site, we demonstrate that neurons with similar disparity selectivity are clustered in both V3 and V3A. We conclude that areas V3 and V3A are not particularly specialized for processing stereoscopic depth information compared to other early visual areas, at least with respect to the tuning properties that we have examined

    Rotor interaction in the annulus billiard

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    Introducing the rotor interaction in the integrable system of the annulus billiard produces a variety of dynamical phenomena, from integrability to ergodicity

    The static quark potential to three loops in perturbation theory

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    The static potential constitutes a fundamental quantity of Quantum Chromodynamics. It has recently been evaluated to three-loop accuracy. In this contribution we provide details on the calculation and present results for the 14 master integrals which contain a massless one-loop insertion.Comment: 6 pages, talk presented at Loops and Legs in Quantum Field Theory 2010, W\"orlitz, Germany, April 25-30, 201

    An energy scale directly related to superconductivity in the high-TcT_c cuprate superconductors: Universality from the Fermi arc picture

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    We have performed a temperature dependent angle-resolved photoemission spectroscopy (ARPES) study of the tri-layer high-TcT_c cuprate superconductor (HTSC) Bi2_2Sr2_2Ca2_2Cu3_3O10+δ_{10+\delta} (Bi2223), and have shown that the \textquotedblleft effective\textquotedblright superconducting (SC) gap Δsc\Delta_{\rm{sc}} defined at the end point of the Fermi arc and the TcT_c (= 110 K) approximately satisfies the weak-coupling BCS-relationship 2Δsc\Delta_{\rm{sc}} = 4.3kBTck_{\rm{B}}T_c. Combining this result with previous ARPES results on single- and double-layer cuprates, we show that the relationship between 2Δsc\Delta_{\rm{sc}} = 4.3kBTck_{\rm{B}}T_c holds for various HTSCs. Furthermore, at TT \sim TcT_c, the quasi-patricle width at the end point of the Fermi arc is found to coincide with Δsc\Delta_{\rm{sc}}, consistent with the context of Planckian dissipation.Comment: 5 pages, 4 figure

    Effect of electron-phonon coupling in the ARPES spectra of the tri-layer cuprate Bi2_2Sr2_2Ca2_2Cu3_3O10+δ_{10+\delta}

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    Angle-resolved photoemission spectroscopy using tunable low energy photons allows us to study the quasi-particle (QP) dispersions of the inner and outer CuO2 planes (IP and OP) separately in the tri-layer cuprate Bi2_2Sr2_2Ca2_2Cu3_3O10+δ_{10+\delta} (Bi2223). The kink energy of the OP band is \sim 70 meV, as observed in various high-TcT_c cuprates, while that of the IP band is as large as 100 meV in the superconducting (SC) state. This large kink energy is attributed to the \sim 35 meV buckling mode plus the large (\sim 60 meV) SC gap of IP. The IP band also shows a weak kink feature at 70 meV in the SC state. The latter feature can be explained either by the 70 meV half-breathing mode or by the \sim 35 meV buckling-phonon mode plus the \sim 40 meV SC gap of OP if interlayer scattering of QP is involved.Comment: 5 pages, 2 figure

    Drug review process advancement and required manufacturer and contract research oraganization responses

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    \ua9 2024 The Japanese Society of Toxicologic Pathology.The United States Senate passed the “FDA Modernization Act 2.0.” on September 29, 2022. Although the effectiveness of this Bill, which aims to eliminate the mandatory use of laboratory animals in new drug development, is limited, it represents a significant trend that will change the shape of drug applications in the United States and other countries. However, pharmaceutical companies have not taken major steps towards the complete elimination of animal testing from the standpoint of product safety, where they prioritize patient safety. Nonetheless, society is becoming increasingly opposed to animal testing, and efforts will be made to use fewer animals and conduct fewer animal tests as a natural and reasonable response. These changes eventually alter the shape of new drug applications. Based on the assumption that fewer animal tests will be conducted or fewer animals will be used in testing, this study explored bioinformatics and new technologies as alternatives to compensate for reduced information and provide a picture of how future new drug applications may look. The authors also discuss the directions that pharmaceutical companies and nonclinical contract research organizations should adopt to promote the replacement, reduction, and refinement of animals used in research, teaching, testing, and exhibitions
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