3,407 research outputs found
INFRARED-RADIOFREQUENCY TWO-PHOTON LAMB DIP SPECTROSCOPY OF AND
No full text S.M. Freund and T. Oka, Appl. Phys. Lett. 21, 60 (1972).Author Institution: Division of Physics, National Research Council of CanadaThe two-photon Lamb dip technique previously applied to ammonia using infrared and microwave is now extended to the radio-frequency region. If a rotational level of a symmetric top molecule with has double parity, a radiofrequency photon can be ``added” directly to an infrared laser photon using the non-linearlity of the molecular transition process. The two-photon Lamb dips observed are listed below. [FIGURE] The observation gives the difference between the laser lines and molecular absorptions with an accuracy of about 0.5 MHz. Precision molecular constants which supplement recent laser-Stark spectroscopy on are obtained. M. R\”omheld was the holder of a German Academic Exchange Service Fellowship
Medicaid, Managed Care, and Kids. 12th Annual Herbert Lourie Memorial Lecture on Health Policy
No full textThis policy brief talks about what managed care for Medicaid is, how it influences kids, and how it relates to the State Child Health Insurance Program (CHIP). It focuses on what we have learned over the last 20 years through research about cost, use, and quality. It also discusses some of the expectations we had for children covered by Medicaid managed care. Finally, it talks abaout the future of Medicaid managed care and the implications for CHIP.
Small but More Sustainable? Business Case and Barriers Perceptions in SMEs and Large Firms
No full textSustainability is more and more becoming a critical success factor for firms; the shared value and business case for sustainability conceptions can support business model change or innovation towards sustainable business models (SBM). Small firms are the most spread organizational model worldwide and can play a relevant role in terms of economic and social development. The corporate social responsibility literature have often depicted small business as less engaged and more constrained with respect to environmental and social practices. This paper aims to translate the organizational size debate in the field of SBM, by analyzing small and large firms’ perceptions about their drivers to business case and their implementation constraints towards a more sustainable business model
CHOLECYSTOKININ-IMMUNOREACTIVE CELLS FORM SYMMETRICAL SYNAPTIC CONTACTS WITH PYRAMIDAL AND NONPYRAMIDAL NEURONS IN THE HIPPOCAMPUS
No full textThe ultrastructural features and synaptic relationships of cholecystokinin (CCK)-immunoreactive cells of rat and cat hippocampus were studied using the unlabeled antibody immunoperoxidase technique and correlated light and electron microscopy. CCK-positive perikarya of variable shape and size were distributed in all layers and were particularly concentrated in stratum pyramidale and radiatum: the CCK-immunoreactive neurons were nonpyramidal in shape and the three most common types had the morphological features of tufted, bipolar, and multipolar cells. Electron microscopic examination revealed that all the CCK-positive boutons established symmetrical (Gray's type II) synaptic contacts with perikarya and dendrites of pyramidal and nonpyramidal neurons. The origin of some of the boutons was established by tracing fine collaterals that arose from the main axon of two CCK-immunostained cells and terminated in the stratum pyramidale; these collaterals were then examined in the electron microscope. The axon of one such neuron exhibited a course parallel to the pyramidal layer and formed pericellular nets of synaptic boutons upon the perikarya of pyramidal neurons. This pattern of axonal arborization is very similar to that of some of the basket cells, previously suggested to be the anatomical correlate for pyramidal cell inhibition. Typical dendrites of pyramidal cells also received symmetrical synaptic contacts from CCK-immunoreactive boutons, and some of these boutons could be shown to originate from a local neuron in stratum radiatum. Many CCK-immunoreactive cells received CCK-labeled boutons upon their soma and dendritic shafts. Synaptic relationship, established by multiple 'en passant' boutons, was observed between CCK-positive interneurons of the stratum lacunosum-moleculare and radiatum. The soma and dendrites of the CCK-immunostained neurons also received symmetrical and asymmetrical synapses from nonimmunoreactive boutons. These results indicate that the CCK-immunoreactive neurons participate in complex local synaptic interactions in the hippocampus
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Freund-schaft: Capturing Aura in an Unframed Literary Exchange
No full textThis dissertation charts an intellectual history of collaborations centered on the beginning of socio-critical discourse on photography. I study the critically misread oeuvre of photographer and sociologist Gisèle Freund to reconfigure a transatlantic map of concrete personal, literary, and critical connections during the 1930s and ’40s. In examining Freund’s oeuvre, I suggest a crucial intervention on the notion of aura — Walter Benjamin’s trademark for understanding the dialectics of the original and its reproduction. I advance a reading in support of aura that challenges the canonical “The Work of Art in the Age of Technical Reproducibility” (1940) of Benjamin. The continuous coexistence of the terms aura, market, and photography is present in Freund – author of iconic photo-portraits of writers such as James Joyce, Virginia Woolf, André Malraux, Jorge Luis Borges or Benjamin. It contests the reduction of the original’s aura and its reproduction to mutually exclusive terms. My counter-reading in fact recovers the prior and wider aura integral to Benjamin’s “Little History of Photography” (1931). It is this cardinal yet neglected piece that inaugurated together with Freund’s La Photographie en France au dix-neuvième siècle (1936) the critical discourse on photography. Walter Benjamin’s presence is dynamically ingrained in Freund’s oeuvre. In addition to their friendship, two additional friends inform Freund’s career. Freund’s mentors were the leading cultural agents in Paris and Buenos Aires: Adrienne Monnier, the legendary French publisher of Joyce’s Ulysses, and Victoria Ocampo, the founding director of Sur, one of the key literary journals in Latin America. The network of cooperative interactions here deployed is conjugated under the critical metaphor Freund-schaft. Coined on Freund’s name, the term draws equally on the meaning of friendship and the creative making contained in the suffix –schaft (derived from the German schaffen, “to make”, “to create”, “to accomplish”). The framework hinges on the tension between history and theory. Freund-schaft brings to light omissions, conjunctions, and the debates that make up the larger structure of feelings, and makes particulars inextricable from a life-woven net
Charge transfer effects and photoemission in transition metal oxides
No full textThe role of charge transfer effects in the X-ray photoelectron spectra of oxides has been studied using a newly developed ab initio model Hamiltonian description for MnO and NiO. The reason that these effects are a minor perturbation for MnO while they are extremely important for NiO is identified as an atomic property of the transition metal cations. This property is the energetic advantage of adding a d electron to the cations which increases rapidly for heavier metal atoms
Are there two forms of Multiple Evanescent White Dot Syndrome?
No full textPurpose: To analyze the nature of multiple evanescent white dot syndrome (MEWDS) and differentiate an idiopathic or primary form of MEWDS from a secondary form that is seen in association with other clinical conditions affecting the posterior segment of the eye. Methods: Clinical and multimodal imaging findings including color fundus photography, fundus autofluorescence, fluorescein angiography, indocyanine green angiography, spectral-domain optical coherence tomography, and optical coherence tomography angiography of patients with secondary MEWDS are presented. Results: Twenty consecutive patients with secondary MEWDS were evaluated. Fifteen patients were female. Most were young adults aged between 20 to 40 years with myopia (less than -6 diopters). Pathologic conditions associated with the secondary MEWDS reaction were high myopia (greater than -6 diopters) in two eyes, previous vitreoretinal surgery for rhegmatogenous retinal detachment in 2 eyes, and manifestations of multifocal choroiditis in 18 eyes. In all eyes, the MEWDS lesions followed a course of progression and resolution independent from the underlying condition. Conclusion: Secondary MEWDS seems to be an epiphenomenon (“EpiMEWDS”) that may be seen in association with clinical manifestations disruptive to the choriocapillaris-Bruch membrane-retinal pigment epithelium complex. Copyright © by Ophthalmic Communications Societ
Kv1 channels in signal conduction of myelinated nerve fibers
No full textPubMedID: 16878404The myelinated axon can be divided into three domains: the internodal axon, the paranodal axon and the nodal axon. The internodal axolemma contains high concentrations of K+ channels that are enriched in the juxtaparanodal region, whereas Na+ channels cluster in the node. This molecular organization of the myelinated axon membrane is critically important for the rapid and successful transmission of electrical impulses. The juxtaparanodal K+ channels are believed to be electrically inactive in adult peripheral nerves, but experiments with blocking drugs and genetic deletion have shown that they may serve important functions at earlier developmental stages, and during remyelination and regeneration. © Freund & Pettman, U.K.SBAG-2554The author thanks Dr. Ismail Gunay for advice and critical assessment of the manuscript, and the many investigators whose work is reviewed here. Work in the author's laboratory has been supported by grants from the Scientific and Technical Research Council of Turkey (SBAG-2554) and Research Foundation of Cukurova University
2-alkenyl-1,2,3-diazabora-5-cyclopentenes products of rearrangement reactions from lithiated ketazines and various halofunctional aryl-, amino- and aryloxyboranes
No full text2-Alkenyl-1,2,3-diazabora-5-cyclopentenes are obtained from the dilithiated tert-butyl(trimethylsilylmethyl)ketazine 1 and BX3 (X = F, Cl): 2, 3 or from a variety of dilithiated ketazines and YBX2 (Y = (Pr2N)-N-t, C6H5, 2,4,6-Bu-3(t)-C6H2, 2,6-Bu-2(t)-C6H3O; X = F, CI): 4 - 7, 9 - 12 or even with (Et2N)(2)BCl: 8. Due to their conjugated pi -system the title compounds are colored (deep orange to bright yellow) and stabilized with respect to other expected products. If the lithiation cannot be achieved on the alpha -C-atom bonded to the nitrogen-atom, lithium is coordinated to the azine N-atom(s), Upon treatment with (Pr2NBF2)-N-t this leads to splitting of the N-N bond of the ketazine and addition of the R2C=N-groups to boron as in 13 or to a borylation of one of the N-atoms as in 14 A C-borylated precursor, 15, was also isolated. The compounds were characterized by NMR: H-1, B-11, C-13, F-19, Si-29; by MS and C,H-elemental analyses. X-ray structure analyses are presented for 6 and 15
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