252,469 research outputs found
Posterior stabilized designs in modern total knee arthroplasty: Vestigial organs
Clinical difference between posterior-stabilized (PS) and cruciate-retaining (CR) designs in total knee arthroplasty has remained elusive for decades. This classic debate has been given pause due to futile efforts to prove one design superior over the other. Recently, anterior-lipped and more conforming CR bearings have emerged to substitute for the posterior-cruciate ligament (PCL), if absent, damaged or resected, and obviate the need for the archaic cam-post mechanism of a traditional PS design. Advantages of avoiding a PS TKA include eliminating the risk of box cut induced femoral condylar fracture, operative efficiency by removing procedural steps, removing the articulation that is a source of wear, post deformation, breakage, or dislocation, and eliminating patellar clunk
Reflecting at the Speed of Light
A perfectly reflecting accelerating boundary produces thermal emission to an
observer at and a finite amount of energy to an observer at
by asymptotically traveling to the speed of light without an
acceleration horizon.Comment: 4 pages, 4 figures; In memory of Kerson Huan
Melt-extruded polyethylene oxide (PEO) rods as drug delivery vehicles: Formulation, performance as controlled release devices and the influence of co-extruded excipients on drug release profiles
The utility of controlled release medication formulations lies in their ability to keep drugs at steady levels in the blood plasma of recipients and within the termini of the maximum and minimum effective therapeutic levels. This avoids the “ups” and “downs” of medication levels within the body which would have been the result had conventional immediate release tablets been administered instead. In the veterinary field, controlled release medications are essential¹ because of the logistical difficulties of administering drugs on a regular (e.g., daily) basis to animals. The chief advantages of controlled release veterinary medications lie in the ease with which they can be administered; decrease in stress for animals, owing to less need for rounding up and frequent dosing; and, most importantly for farmers, the reduced cost of treatment relative to that for a multiple dosage regime
Extreme Hawking Radiation
Modeling the collapse of an extreme Reissner-Nordstr\"om (ERN) black hole by
solving the corresponding moving mirror model for the trajectory that
asymptotically approaches uniform acceleration, we obtain the non-zero beta
coefficients for all times. Finite energy is emitted, the radiation spectra is
non-thermal (non-steady / not Planck), soft particles characterize the
evaporation, and particle production at ultra-late times is damped.
Entanglement entropy diverges with no Page curve turn-over, demonstrating
non-thermal information loss. The radiation obeys time-reversal symmetry.Comment: 11 pages, 12 figure
Effective potential and warp factor dynamics
We define an effective potential describing all massless and massive modes in
the supergravity limit of string/M theory compactification which is valid
off-shell, i.e. without imposing the equations of motion. If we neglect the
warp factor, it is unbounded below, as is the case for the action in Euclidean
quantum gravity. By study of the constraint which determines the warp factor,
we solve this problem, obtaining a physically satisfying and tractable
description of the dynamics of the warp factor.Comment: 32 pages, JHEP3.cls. v4: added reference to hep-th/050715
The Logical Structure of Consciousness (behavior, personality, rationality, higher order thought, intentionality)
After half a century in oblivion, the nature of consciousness is now the hottest topic in the behavioral sciences and philosophy. Beginning with the pioneering work of Ludwig Wittgenstein in the 1930’s (the Blue and Brown Books) and from the 50’s to the present by his logical successor John Searle, I have created the following table as an heuristic for furthering this study. The rows show various aspects or ways of studying and the columns show the involuntary processes and voluntary behaviors comprising the two systems (dual processes) of the Logical Structure of Consciousness (LSC), which can also be regarded as the Logical Structure of Rationality (LSR-Searle), of behavior (LSB), of personality (LSB), of reality (LSOR), of Intentionality (LSI) -the classical philosophical term, the Descriptive Psychology of Consciousness (DPC) , the Descriptive Psychology of Thought (DPT) –or better, the Language of the Descriptive Psychology of Thought (LDPT), terms introduced here and in my other very recent writings.
Those wishing a comprehensive up to date framework for human behavior from the modern two systems view may consult my book ‘The Logical Structure of Philosophy, Psychology, Mind and Language in Ludwig Wittgenstein and John Searle’ 2nd ed (2019). Those interested in more of my writings may see ‘Talking Monkeys--Philosophy, Psychology, Science, Religion and Politics on a Doomed Planet--Articles and Reviews 2006-2019 3rd ed (2019), The Logical Structure of Human Behavior (2019), and Suicidal Utopian Delusions in the 21st Century 4th ed (2019
Re-Imagining Journalism: Local News for a Networked World
Details strategies for realizing healthy local information ecologies through for-profit and nonprofit media; higher education and community institutions; emphasis on relevance, research, and revenues; and government support. Includes case summaries
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