1,162 research outputs found
Raman signature of electron-electron correlation in chemically doped few-layer graphene
We report an experimental Raman study of few-layer graphene after chemical
doping achieved by a plasma process in CHF gas. A systematic reduction of
both the splitting and the area of the 2D band is observed with increasing the
doping level. Both effects can be ascribed to the electron-electron
correlation, which on the one hand reduces the electron-phonon coupling
strength, and on the other hand affects the probability of the double resonant
Raman process
Observation of Raman G-band splitting in top-doped few-layer graphene
An experimental study of Raman scattering in N-layer graphene as a function
of the top layer doping is reported. At high doping level, achieved by a CHF_3
plasma treatment, we observe a splitting of the band in the spectra of
bilayer and 4-layer graphene (N even), whereas the splitting is not visible in
case of monolayer and trilayer graphene (N odd). The different behaviors are
related to distinct electron-phonon interactions, which are affected by
symmetry breaking and Fermi level position in different ways in the various
N-layer graphenes. In trilayer graphene, a weakening of the electron-phonon
coupling as a function of the Fermi energy induces a hardening of all
zone-center in-plane optical phonon modes, like in monolayer graphene. On the
other hand, in 4-layer graphene two distinct trends are observed in the G band
as a function of doping, suggesting the presence of two different groups of
electron-phonon interactions, like in bilayer graphene.Comment: 7 pages, 6 figures, to be published in PR
Histopathologic and biochemical liver test abnormalities in chronic asymptomatic or oligosymptomatic alcoholics: a review
PURPOSE: To review the medical literature regarding the histopathologic and biochemical liver test abnormalities in chronic asymptomatic or oligosymptomatic alcoholics. METHODS: Review of articles in the MEDLINE and LILACS databases regarding serum levels and prevalence of alterations in aspartate-aminotransferase, alanine-aminotransferase, alkaline phosphatase, and total bilirubin, in relation to liver histopathology, with or without discrimination of types of histopathologic alteration. RESULTS: Global mean prevalence rates of aspartate-aminotransferase and alanine-aminotransferase alterations were 86.3% and 51.1%; in cases with steatosis they were 79.1% and 38.5%; and in cases of hepatitis, 90.1% and 58%. In all studies, prevalence rates of aspartate-aminotransferase alterations were significantly higher with lower variability than those of alanine-aminotransferase. Mean aspartate-aminotransferase levels were higher than 2N (N is the upper normal limit of the method employed) in all cases with hepatitis histopathology, while those of alanine-aminotransferase were 1.48N, in the same cases. Prevalence of alkaline phosphatase and total bilirubin abnormalities were 74.5% and 74.9% globally; in cases of steatosis, they were 70.9% and 67.9%; and in cases of hepatitis, 75.9% and 77.7%. Mean alkaline phosphatase levels were above the upper normal limit in all cases, but those of total bilirubin were above normal in 4 of 7 hepatitis studies. CONCLUSIONS: Prevalence of aspartate-aminotransferase alteration was consistently related to presence of histopathologic abnormalities; an enzyme level higher than 2N suggests the diagnosis of alcoholic hepatitis.OBJETIVO: Revisar a literatura mĂ©dica referente Ă s relações entre alterações histopatolĂłgicas e testes bioquĂmicos hepáticos em alcoolistas crĂ´nicos assintomáticos ou oligossintomáticos. MÉTODOS: Levantamento, a partir das bases de dados MEDLINE e LILACS e referĂŞncias em publicações, das prevalĂŞncias de alterações e nĂveis sĂ©ricos da aspartato-aminotransferase, alanino-aminotransferase, fosfatase alcalina e bilirrubina total relacionados com a histopatologia hepática, com e sem discriminação do tipo de alteração histopatolĂłgica. RESULTADOS: As taxas mĂ©dias das prevalĂŞncias da aspartato-aminotransferase e alanino-aminotransferase foram 86,3% e 51,1% globalmente, sendo 79,1% e 38,5% nos casos de esteatose e 90,1% e 58% nos casos de hepatite, respectivamente. As taxas das prevalĂŞncias das alterações da aspartato-aminotransferase foram, em todos os estudos, significativamente mais altas e mostraram menores variações que aquelas da alanino-aminotransferase. Os nĂveis mĂ©dios da aspartato-aminotransferase foram maiores que 2N (duas vezes superior o limite superior da normalidade) em todos os casos com histopatologia de hepatite, enquanto que os da alanino-aminotransferase, nos mesmos casos, foram 1,48N. As prevalĂŞncias de alterações da fosfatase alcalina e bilirrubina total foram 74,5% e 74,9% globalmente, 70,9% e 67,9% nos casos de esteatose e 75,9% e 77,7% nos casos de hepatite, respectivamente. Em todos os casos de hepatite, os nĂveis mĂ©dios da fosfatase alcalina estavam acima do limite superior da normalidade. Em 4 de 7 estudos sobre pacientes com hepatite a mĂ©dia da bilirrubina total estava acima do normal. CONCLUSĂ•ES: As prevalĂŞncias de alterações da aspartato-aminotransferase foram consistentemente relacionadas a presença de alterações histopatolĂłgicas e o nĂvel elevado da enzima, maior que 2N do mĂ©todo de determinação, sugere o diagnĂłstico de hepatite alcoĂłlica
Working with the Revenue code - 1973
https://egrove.olemiss.edu/aicpa_guides/2767/thumbnail.jp
Outlook for Tax Incdentives: The Natural and Extractive Industries, Plenary Session, October 16, 1973, Atlanta Marriott
https://egrove.olemiss.edu/aicpa_assoc/1973/thumbnail.jp
Working with the Revenue Code 1974
https://egrove.olemiss.edu/aicpa_guides/2779/thumbnail.jp
A função de sĂntese hepática em alcoolistas crĂ´nicos assintomáticos ou oligossintomáticos. Correlações com outros testes hepáticos
Liver function and its correlation with bilirubin and hepatic enzymes were evaluated in 30 male chronic asymptomatic or oligosymptomatic alcoholics admitted into the psychiatric hospital for detoxification and treatment of alcoholism. Hypoalbuminemia, lowered prothrombin activity, hypotransferrinemia and hypofibrinogenemia were detected in 32 %, 32 %, 28 %, and 24 % of patients, respectively. Transferrin was elevated in 8 %. Greater prevalence of hyperbilirubinemia was found in patients with lowered prothrombin activity, hypofibrinogenemia, or hypotransferrinemia. No correlation was found between serum bilirubin or aminotransferase levels and normal or elevated albumin levels, time or activity of prothrombin, and fibrinogen levels. Serum alkaline phosphatase was elevated in normoalbuminemics and gamma-glutamyltransferase in patients with lowered prothrombin activity. Hypoalbuminemia was associated with hypofibrinogenemia, hypotransferrinemia with elevated aspartate aminotransferase or gamma-glutamyltransferase, and hypertransferrinemia with elevation of alanine aminotransferase. These data indicated the occurrence of hepatic dysfunction due to liver damage caused directly by alcohol or by alcoholism-associated nutritional deficiencies.A função hepática e suas correlações com a bilirrubina e as enzimas hepáticas foram avaliados em 30 alcoolistas crĂ´nicos do sexo masculino, assintomáticos ou oligossintomáticos, internados em hospital psiquiátrico para desintoxicação e tratamento do alcoolismo. Hipoalbuminemia, hipoatividade da protrombina, hipofibrinogenemia e hipotransferrinemia ocorreram em 32%, 32%, 24% e 28% dos pacientes, respectivamente. A transferrina estava elevada em 8%. Maior prevalĂŞncia de hiperbilirrubinemia foi encontrada em pacientes com hipoatividade da protrombina, hipofibrinogemia e hipotransferrinemia. NĂŁo observou-se correlações entre os nĂveis sĂ©ricos da bilirrubina e das aminotransferases e os nĂveis normais ou diminuĂdos da albumina, do tempo e atividade da protrombina e fibrinogĂŞnio. Os nĂveis sĂ©ricos da fosfatase alcalina estavam mais elevados nos pacientes com normoalbuminemia enquanto que os da gama-glutamiltransferase nos com hipoatividade da protrombina. Hipoalbuminemia estava associada com hipofibrinogenemia, hipotransferrinemia com elevações da aspartato aminotransferase e gamaglutamiltransferase, e hipertransferrinemia com elevação da alanino aminotransferase. Estes dados indicam a ocorrĂŞncia de disfunção hepática devida a lesĂŁo hepática causada diretamente por deficiĂŞncias nutritivas associadas ao alcoolismo
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The impact of social and relational contexts on innovation transfer in foreign subsidiaries
It is widely acknowledged that innovation is one of the pillars of multinational enterprises (MNEs) and that
technological knowledge from different host locations is a key factor to the MNEs’ competitive advantages
development. Concerning these assumptions, in this paper we aim to understand how the social and the
relational contexts affect the conventional and reverse transfer of innovation from MNEs’ subsidiaries
hosted in emerging markets. We analyzed the social context through the institutional profile (CIP) level
and the relational context through trust and integration levels utilizing a survey sent to 172 foreign
subsidiaries located in Brazil, as well as secondary data. Through an ordinary least squares regression
(OLS) analysis we found that the relational context affects the conventional and reverse innovation transfer
in subsidiaries hosted in emerging markets. We however did not find support for the social context effect
Huge (but finite) time scales in slow relaxations: beyond simple aging
Experiments performed in the last years demonstrated slow relaxations and
aging in the conductance of a large variety of materials. Here, we present
experimental and theoretical results for conductance relaxation and aging for
the case-study example of porous silicon. The relaxations are experimentally
observed even at room temperature over timescales of hours, and when a strong
electric field is applied for a time , the ensuing relaxation depends on
. We derive a theoretical curve and show that all experimental data
collapse onto it with a single timescale as a fitting parameter. This timescale
is found to be of the order of thousands of seconds at room temperature. The
generic theory suggested is not fine-tuned to porous silicon, and thus we
believe the results should be universal, and the presented method should be
applicable for many other systems manifesting memory and other glassy effects.Comment: 4+ pages, 4 figure
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