457 resultados para Huntington


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Mode of access: Internet.

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Vols. [18]- include indexes of animals and lists of transfers.

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Photostatic reproduction, on 3 leaves, of the copy in the Henry E. Huntington Library and art gallery.

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[14] Apr. 7, 1924. Miscellaneous literature. 652 lots.--[15] March 23, 1925. Early English poetry and other literature. 692 lots.--[16] March 30, 1925. Early English Works on the arts and sciences. 797 lots.--[17] March 15, 1926. Early English poetry and other literature. 707 lots.--[18] March 22, 1926. Early English law and history. 570 lots.--[19] March 28, 1927. Final portion. 2151 lots.--[20] July 11, 1927. Books unsold or returned as imperfect. 183 lots.--[21] July 25, 1927. Books omitted from the sales of the Britwell Court Library. The property of S.R. Christie-Miller. 31 lots. (In Sotheby, firm, auctioneers, London. Catalogue of valuable printed books, illuminated and other manuscripts ... which will be sold ... Monday, 25th of July and two following days ... London [1927] p. 70-75, lots 456-486)

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Alzheimer's disease (AD) is the most common form of dementia, accounting for 60-70% of cases in subjects over 65 years of age. Several postulates have been put forward that relate AD neuropathology to intellectual and functional impairment. These range from free-radical-induced damage, through cholinergic dysfunction, to beta-amyloid-induced toxicity. However, therapeutic strategies aimed at improving the cognitive symptoms of patients via choline supplementation, cholinergic stimulation or beta-amyloid vaccination, have largely failed. A growing body of evidence suggests that perturbations in systems using the excitatory amino acid L-glutamate (L-Glu) may underlie the pathogenic mechanisms of (e.g.) hypoxia-ischemia, epilepsy, and chronic neurodegenerative disorders such as Huntington's disease and AD. Almost all neurons in the CNS carry the N-methyl-D-aspartate (NMDA) subtype of ionotropic L-glutamate receptors, which can mediate post-synaptic Ca2+ influx. Excitotoxicity resulting from excessive activation of NMDA receptors may enhance the localized vulnerability of neurons in a manner consistent with AD neuropathology, as a consequence of an altered regional distribution of NMDA receptor subtypes. This review discusses mechanisms for the involvement of the NMDA receptor complex and its interaction with polyamines in the pathogenesis of AD. NMDA receptor antagonists have potential for the therapeutic amelioration of AD. (C) 2004 Elsevier Ltd. All rights reserved.

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We describe a scheme for the encoding and manipulation of single photon qubits in optical sideband modes using standard optical elements. We propose and analyze the radio frequency half-wave plate, which may be used to make arbitrary rotations of a state in the frequency basis, and the frequency beamsplitter, which may be used to separate (or combine) photons of different frequencies into (from) different spatial modes.

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Quantum optics experiments on bright beams are based on the spectral analysis of field fluctuations and typically probe correlations between radio-frequency sideband modes. However, the extra degree of freedom represented by this dual-mode picture is generally ignored. We demonstrate the experimental operation of a device which can be used to separate the quantum sidebands of an optical field. We use this device to explicitly demonstrate the quantum entanglement between the sidebands of a squeezed beam.

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We demonstrate a device that allows for the coherent analysis of a pair of optical frequency sidebands in an arbitrary basis. We show that our device is quantum noise limited, and hence applications for this scheme may be found in discrete and continuous variable optical quantum information experiments. (c) 2005 Optical Society of America.

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Focussing particularly on solid-state laser systems, the phase-noise penalties of laser injection-locking and electro-optical phase-locking are derived using linearised quantum mechanical models. The fundamental performance limit (minimum achievable output phase noise) for an injection-locked laser (IJL) system at low frequencies is equal to that of a standard phase-insensitive amplifier, whereas, in principle, that of a phase-locked laser (PLL) system can be better. At high frequencies, the output phase noise of the IJL system is limited by that of the master laser, while that of the PLL system tends to a weighted sum of contributions from the master and slave laser fields. Under conditions of large amplification, particularly where there has been significant attenuation, the noise penalties are shown to be substantial. Nonideal photodetector characteristics are shown to add significantly to the noise penalties for the PLL system. (C) 2005 Elsevier B.V. All rights reserved.

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Neurodegenerative diseases such as Huntington's disease, ischemia, and Alzheimer's disease (AD) are major causes of death. Recently, metabotropic glutamate receptors (mGluRs), a group of seven-transmembrane-domain proteins that couple to G-proteins, have become of interest for studies of pathogenesis. Group I mGluRs control the levels of second messengers such as inositol 1,4,5-triphosphate (IP3) Cal(2+) ions and cAMP. They elicit the release of arachidonic acid via intracellular Ca2+ mobilization from intracellular stores such as mitochondria and endoplasmic reticulum. This facilitates the release of glutamate and could trigger the formation of neurofibrillary tangles, a pathological hallmark of AD. mGluRs regulate neuronal injury and survival, possibly through a series of downstream protein kinase and cysteine protease signaling pathways that affect mitochondrially mediated programmed cell death. They may also play a role in glutamate-induced neuronal death by facilitating Cal(2+) mobilization. Hence, mGluRs have become a target for neuroprotective drug development. They represent a pharmacological path to a relatively subtle amelioration of neurotoxicity because they serve a modulatory rather than a direct role in excitatory glutamatergic transmission.

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Since the late 1980s, it has been increasingly recognized that the experiences of people with dementia have been omitted from research in the area of dementia and memory loss. More recently, it has been accepted that people with dementia have insight into their condition and, therefore, the ability to contribute to research. A qualitative research project was undertaken with nine participants to explore the experiences and coping strategies of people with dementia. Interviews were undertaken and the data analysed using thematic analysis. Three major themes emerged: coming to terms with memory loss, maintaining control and independence, and the impact of illness on relationships. Understanding the reality for people is essential given that representations of the catastrophic impact of dementia generate high levels of anxiety and depression. Implications for nurses' practice include the need for skilled, well-paced, sensitive and ongoing information about the condition, along with the need to recognize and support the active coping strategies of people with memory loss.