260,506 research outputs found
Remarks on the number of tubulin dimers per neuron and implications for Hameroff-Penrose Orch OR
Stuart Hameroff has wrongly estimated that a typical brain neuron has 10^7^ tubulin dimers and wrongly attributed this result to Yu and Baas, J. Neurosci. 1994; 14: 2818-2829. In this letter we show that Hameroff’s estimate is based on misunderstanding of the results provided by Yu and Baas, who actually measured the total microtubule length in a single axonal projection with length of 56 μm in a differentiating in vitro stage 3 embryonic hippocampal neuron. In order to visualize how big Hameroff’s error is, we have reconstructed two of the studied by Yu and Baas embryonic hippocampal neurons with Neuromantic v1.6.3 and compared them with previously published reconstructions of adult hippocampal neurons. Correct calculations show that an adult differentiated pyramidal neuron in vivo has approximately 1.3×10^9^ tubulin dimers incorporated in cytoskeletal microtubules. This estimate has profound implications for the Hameroff-Penrose Orch OR model, because it sets limitations on the number of quantum coherent neurons and implies that if 100% of the neuronal microtubules are quantum coherent for 25 ms then Hameroff-Penrose Orch OR conscious events should involve only 15 pyramidal neurons
Local-dephasing-induced entanglement sudden death in two-component finite-dimensional systems
Entanglement sudden death (ESD), the complete loss of entanglement in finite
time, is demonstrated to occur in a class of bipartite states of qu-d-it pairs
of any finite dimension d > 2, when prepared in so-called `isotropic states'
and subject to multi-local dephasing noise alone. This extends previous results
for qubit pairs [T. Yu, J. H. Eberly, Phys. Rev. Lett. 97, 140403 (2006)] to
all qu-d-it pairs with d > 2.Comment: 8 pages, to appear in Phys. Rev.
Correction: Thermoresponsive polysarcosine-based nanoparticles
Correction for ‘Thermoresponsive polysarcosine-based nanoparticles’ by Huayang Yu et al., J. Mater. Chem. B, 2019, 7, 4217–4223
Sudden Death of Entanglement: Classical Noise Effects
When a composite quantum state interacts with its surroundings, both quantum
coherence of individual particles and quantum entanglement will decay. We have
shown that under vacuum noise, i.e., during spontaneous emission, two-qubit
entanglement may terminate abruptly in a finite time [T. Yu and J. H. Eberly,
\prl {93}, 140404 (2004)], a phenomenon termed entanglement sudden death (ESD).
An open issue is the behavior of mixed-state entanglement under the influence
of classical noise. In this paper we investigate entanglement sudden death as
it arises from the influence of classical phase noise on two qubits that are
initially entangled but have no further mutual interaction.Comment: 5 pages, 1 figur
Bizarre structures in dinosaurs: species recognition or sexual selection? A response to Padian and Horner
Subtropical middle atmosphere dynamics observed by the Chung Li radar
The Chung Li Radar (24.91 N; 121.24 E) has been operating since 1986. A five beam observational configuration was used on a regular basis to study the various dynamics processes in the atmosphere-lower stratosphere height region. Due to its geographical location, the annual Typhoon and Mei-Yu seasons provide good opportunities to study the various interesting dynamic processes such as instabilities, generation of gravity waves, wave mean field interaction, etc. Three dimensional air motions due to these fronts are presented. Special cases of gravity wave generation, propagation and their effects on the turbulent layers are discussed
Bilateral Hipoglossal Nerve Palsy In Necrotizing Otitis Externa
[No abstract available]734576Benecke Jr., J.A., Management of osteomyelitis of the skull base (1989) Laryngoscope, 99 (12), pp. 1220-1223Boringa, J.B., Hoekstra, O.S., Roos, J.W., Bertelsmann, F.W., Multiple cranial nerve palsy after otitis externa: A case report (1995) Clin Neurol Neurosurg, 97, pp. 332-335Rubin, J., Yu, V.L., Malignant external otitis: Insights into pathogenesis, clinical manifestations and therapy (1998) Am J Med, 85, pp. 391-39
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