2,330 research outputs found
Neural activity in the visual thalamus reflects perceptual suppression
To examine the role of the visual thalamus in perception, we recorded neural activity in the lateral geniculate nucleus (LGN) and pulvinar of 2 macaque monkeys during a visual illusion that induced the intermittent perceptual suppression of a bright luminance patch. Neural responses were sorted on the basis of the trial-to-trial visibility of the stimulus, as reported by the animals. We found that neurons in the dorsal and ventral pulvinar, but not the LGN, showed changes in spiking rate according to stimulus visibility. Passive viewing control sessions showed such modulation to be independent of the monkeys' active report. Perceptual suppression was also accompanied by a marked drop in low-frequency power (9–30 Hz) of the local field potential (LFP) throughout the visual thalamus, but this modulation was not observed during passive viewing. Our findings demonstrate that visual responses of pulvinar neurons reflect the perceptual awareness of a stimulus, while those of LGN neurons do not
Wave Energy Technology Development Review in the UK: Application of the Learning Curve Concept, 1970-1999
Sensitivity Analysis and Machine Learning Modelling for the Output Characteristics of Rotary HTS Flux Pumps
Internal quantum reference frames for finite Abelian groups
Employing internal quantum systems as reference frames is a crucial concept
in quantum gravity, gauge theories and quantum foundations whenever external
relata are unavailable. In this work, we give a comprehensive and
self-contained treatment of such quantum reference frames (QRFs) for the case
when the underlying configuration space is a finite Abelian group,
significantly extending our previous work (Quantum 5, 530 (2021)). The
simplicity of this setup admits a fully rigorous quantum information-theoretic
analysis, while maintaining sufficient structure for exploring many of the
conceptual and structural questions also pertinent to more complicated setups.
We exploit this to derive several important structures of constraint
quantization with quantum information-theoretic methods and to reveal the
relation between different approaches to QRF covariance. In particular, we
characterize the "physical Hilbert space" -- the arena of the
"perspective-neutral" approach -- as the maximal subspace that admits
frame-independent descriptions of purifications of states. We then demonstrate
the kinematical equivalence and, surprising, dynamical inequivalence of the
"perspective-neutral" and the "alignability" approach to QRFs. While the former
admits unitaries generating transitions between arbitrary subsystem relations,
the latter, remarkably, admits no such dynamics when requiring
symmetry-preservation. We illustrate these findings by example of interacting
discrete particles, including how dynamics can be described "relative to one of
the subsystems".Comment: 22 pages, 1 figure. V2: close to published versio
Detecting Partial Demagnetization in AFPM Generators by Monitoring Speed and EMF Induced in a Supplemental Winding
THADA regulates the organismal balance between energy storage and heat production
Human susceptibility to obesity is mainly genetic, yet the underlying evolutionary drivers causing variation from person to person are not clear. One theory rationalizes that populations that have adapted to warmer climates have reduced their metabolic rates, thereby increasing their propensity to store energy. We uncover here the function of a gene that supports this theory. THADA is one of the genes most strongly selected during evolution as humans settled in different climates. We report here that THADA knockout flies are obese, hyperphagic, have reduced energy production, and are sensitive to the cold. THADA binds the sarco/ER Ca2+ ATPase (SERCA) and acts on it as an uncoupler. Reducing SERCA activity in THADA mutant flies rescues their obesity, pinpointing SERCA as a key effector of THADA function. In sum, this identifies THADA as a regulator of the balance between energy consumption and energy storage, which was selected during human evolution
Analysis of Tower Shadow Effects on Battery Lifetime in Standalone Hybrid Wind-Diesel-Battery Systems
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