612 research outputs found

    Strain-dependent Optical Emission In In1 - Xgaxas/inp Quantum Wells

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    InGaAs/InP strained-layer modulation -doped quantum wells were studied by photoluminescence. The combination of the built-in strain and the quantum confinement in this system leads to a strong valence band mixing yielding direct and indirect band gap structures. We demonstrate that the optical emission line shape is strongly dependent on the valence band dispersion and it is a good method to distinguish between direct and indirect structures. The application of an external biaxial tensile strain to the samples provides an additional evidence of direct-to-indirect band gap transition in strained heterostructures.641515330111533014Gershoni, D., Vandenberg, J.M., Hamm, R.A., Temkin, H., Panish, M.B., (1987) Phys. Rev. B, 36, p. 1320Gershoni, D., Temkin, H., Vandenberg, J.M., Chu, S.N.G., Hamm, R.A., Panish, M.B., (1988) Phys. Rev. Lett., 60, p. 448Gershoni, D., Temkin, H., Panish, M.B., Hamm, R.A., (1989) Phys. Rev. B, 39, p. 5531Chao, C.Y.-P., Chuang, S.L., (1992) Phys. Rev. B, 46, p. 4110Sugawara, M., Okazaki, N., Fujii, T., Yamazaki, S., (1993) Phys. Rev. B, 48, p. 8102Michler, P., Hangleiter, A., Moritz, A., Fuchs, G., Härle, V., Scholz, F., (1993) Phys. Rev. B, 48, p. 111991Triques, A.L.C., Brum, J.A., (1995) Proceedings of the 22nd International Conference on the Physics of Semiconductors, Vancouver, Canada, 1994, 2, pp. 1328-1331. , edited by D.J. Lockwood (World Scientific)Weihofen, R., Weiser, G., Starck, Ch., Simes, R.J., (1995) Phys. Rev. B, 51, p. 4296Dalfors, J., Lundström, R., Holtz, P.O., Radamson, H.H., Monemar, B., Wallin, J., Landgren, G., (1997) Appl. Phys. Lett., 71, p. 503Hosea, T.J.C., Rowland, G., (1998) Supercond. Sci. Technol., 13, p. 207Tudury, H.A.P., Ribeiro, E., Iikawa, F., Brum, J.A., Bernussi, A.A., Carvalho W., Jr., Gobbi, A., unpublishedBastard, G., Brum, J.A., (1986) IEEE J. Quantum Electron., 22, p. 1625Bastard, G., (1992) Wave Mechanics Applied to Semiconductor Heterostructures, , Les Editions de Physique, ParisBaptizmanskii, V.V., Novak, I.I., Titovets, Yu.F., (1979) Sov. Phys. Solid State, 21, p. 1915Liarokapis, E., Richter, W., (1992) Meas. Sci. Technol., 3, p. 347Thewalt, M.L.W., Harrison, D.A., Reinhart, C.F., Wolk, J.A., Lafontaine, H., (1997) Phys. Rev. Lett., 79, p. 26

    A New Strategy To Identify Rare Blood Donors: Single Polymerase Chain Reaction Multiplex Snapshot Reaction For Detection Of 16 Blood Group Alleles

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    Background. As an alternative to phenotyping, large-scale DNA-based assays, which are feasible for high-throughput donor red blood cell typing, were developed for determination of blood group polymorphisms. However, high-throughput genotyping platforms based on these technologies are still expensive and the inclusion of single nucleotide polymorphisms and analysis of the alleles depend on the manufacturer's determination. To overcome this limitation and in order to develop an assay to enable the screening of rare donors, we developed a SNaPshot assay for analysis of nine single nucleotide polymorphisms related to antigens that are difficult to assess using conventional serology. Materials and methods. The single polymerase chain reaction multiplex SNaPshot reaction was optimized to identify nine single nucleotide polymorphisms determining 16 alleles: KEL*3/KEL*4, KEL*6/KEL*7, DI*1/DI*2, DI*3/DI*4, YT*1/YT*2, CO*1/CO*2, DO*1/DO*2, DO*4, DO*5. We designed a single multiplex PCR with primers encompassing the blood group single nucleotide polymorphisms and performed an internal reaction with probe primers able to discriminate the alleles after fragment analysis. The SNaPshot assay was validated with 140 known alleles previously determined by PCR restriction fragment length polymorphism. Results. We were able to simultaneous detect nine single nucleotide polymorphisms defining 16 blood group alleles on an assay based on a multiplex PCR combined with a single base extension using genomic DNA. Discussion. This study demonstrates a robust genotyping strategy for conducting rare donor screening which can be applied in blood centers and could be an important tool for identifying antigen-negative donors and, therefore, for providing rare blood. © SIMTI Servizi Srl.12SUPPL.1s256s263Jungbauer, C., Routine use of DNA testing for red cell antigens in blood centres (2011) Transfus Apher Sci, 45, pp. 61-68Nance, S.T., How to find, recruit and maintain rare blood donors (2009) Curr Opin Hematol, 16, pp. 503-508Veldhuisen, B., Van Der Schoot, C.E., De Haas, M., Blood group genotyping: From patient to high-throughput donor screening (2009) Vox Sang, 97, pp. 198-206Moulds, J.M., Future of molecular testing for red blood cell antigens (2010) Clin Lab Med, 30, pp. 419-429Patnaik, S.K., Helmberg, W., Blumenfeld, O.O., BGMUT: NCBI dbRBC database of allelic variations of genes encoding antigens of blood group systems (2012) Nucleic Acids Res, 40, pp. D1023-D1029Vallone, P.M., Butler, J.M., AutoDimer: A screening tool for primer-dimer and hairpin structures (2004) Biotechniques, 37, pp. 226-231Baleotti Jr., W., Rios, M., Reid, M.E., Dombrock gene analysis in Brazilian people reveals novel alleles (2006) Vox Sang, 91, pp. 81-87Rios, M., Hue-Roye, K., Oyen, R., Insights into the Holleyand Joseph- phenotypes (2002) Transfusion, 42, pp. 52-58Baleotti Jr., W., Rios, M., Reid, M.E., A novel DI*A allele without the Band 3-Memphis mutation in Amazonian Indians (2003) Vox Sang, 84, pp. 326-330Arnoni, C., Latini, F.R.M., Person, R.M., Padronização das técnicas de PCR-RFLP para genotipagem dos alelos KEL*3/ KEL*4 e KEL*5/KEL*6 (2011) Rev Bras Hematol Hemoter, 33 (SUPPL.2), pp. 332-488Baleotti Jr., W., Suzuki, R.B., Ruiz, M., A PCR-RFLP strategy for Wright typing (2011) Rev Bras Hematol Hemoter, 33 (SUPPL. 2), pp. 332-488Brazilian Real - United States Dollar Exchange Rate from Central Bank of Brazil, , http://www4.bcb.gov.br/pec/taxas, April 1st to April 30th, 27/03/2013Daniels, G., The molecular genetics of blood group polymorphism (2009) Hum Genet, 126, pp. 729-742Logdberg, L., Reid, M.E., Zelinski, T., Human blood group genes 2010: Chromosomal locations and cloning strategies revisited (2011) Transfus Med Rev, 25, pp. 36-46Di Cristofaro, J., Silvy, M., Chiaroni, J., Bailly, P., Single PCR multiplex SNaPshot reaction for detection of eleven blood group nucleotide polymorphisms: Optimization, validation, and one year of routine clinical use (2010) J Mol Diagn, 12, pp. 453-460Ferri, G., Pelotti, S., Multiplex ABO genotyping by minisequencing (2009) Methods Mol Biol, 496, pp. 51-58Palacajornsuk, P., Halter, C., Isakova, V., Detection of blood group genes using multiplex SNaPshot method (2009) Transfusion, 49, pp. 740-749Silvy, M., Simon, S., Gouvitsos, J., Weak D and DEL alleles detected by routine SNaPshot genotyping: Identification of four novel RHD alleles (2011) Transfusion, 51, pp. 401-411Silvy, M., Di Cristofaro, J., Beley, S., Identification of RHCE and KEL alleles in large cohorts of Afro-Caribbean and Comorian donors by multiplex SNaPshot and fragment assays: A transfusion support for sickle cell disease patients (2011) Br J Haematol, 154, pp. 260-270Pastinen, T., Kurg, A., Metspalu, A., Minisequencing: A specific tool for DNA analysis and diagnostics on oligonucleotide arrays (1997) Genome Res, 7, pp. 606-614Syvanen, A.C., From gels to chips: "Minisequencing" primer extension for analysis of point mutations and single nucleotide polymorphisms (1999) Hum Mutat, 13, pp. 1-10Information notebook (2011) Blood and Hemoderivates Brasília, , Ministério da Saúde. Secretaria de Atenção à Saúde. Coordenação-Geral de Sangue e Hemoderivados. Hemotherapy production. Unified Health System - SUS Brazil - (Public and private contractors). Private non-contracted services by Unified Health System (SUS Brazil). 4th edSantos, N.P., Ribeiro-Rodrigues, E.M., Ribeiro-Dos-Santos, A.K., Assessing individual interethnic admixture and population substructure using a 48-insertion-deletion (INSEL) ancestry-informative marker (AIM) panel (2010) Hum Mutat, 31, pp. 184-190Storry, J.R., Human blood groups: Inheritance and importance in transfusion medicine (2003) J Infus Nurs, 26, pp. 367-37

    Recomendações Para O Tratamento Da Crise Migranosa - Um Consenso Brasileiro

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    In this article, a group of experts in headache management of the Brazilian Headache Society developed through a consensus strategic measurements to treat a migraine attack in both the child and the adult. Particular emphasis was laid on the treatment of migraine in women, including at pregnancy, lactation and perimenstrual period. © 2016, Associacao Arquivos de Neuro-Psiquiatria. All rights reserved.74326227

    An assessment of Evans' unified field theory I

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    Evans developed a classical unified field theory of gravitation and electromagnetism on the background of a spacetime obeying a Riemann-Cartan geometry. This geometry can be characterized by an orthonormal coframe theta and a (metric compatible) Lorentz connection Gamma. These two potentials yield the field strengths torsion T and curvature R. Evans tried to infuse electromagnetic properties into this geometrical framework by putting the coframe theta to be proportional to four extended electromagnetic potentials A; these are assumed to encompass the conventional Maxwellian potential in a suitable limit. The viable Einstein-Cartan(-Sciama-Kibble) theory of gravity was adopted by Evans to describe the gravitational sector of his theory. Including also the results of an accompanying paper by Obukhov and the author, we show that Evans' ansatz for electromagnetism is untenable beyond repair both from a geometrical as well as from a physical point of view. As a consequence, his unified theory is obsolete.Comment: 39 pages of latex, modified because of referee report, mistakes and typos removed, partly reformulated, taken care of M.W.Evans' rebutta

    Efeitos dos excessos de alumínio, cloro e manganês em dois cultivares de soja (Glycine max (L.) Merrill)

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    Two soybean cultivars, Santa Rosa and FV-1, were grown in nutrient solution in the presence of high concentrations of Al (24 ppm), CI (1750 ppm) and Mn (25 ppm). Observations, measurements and chemical analyses allowed for the following conclusions to be drawn: (1) symptoms of toxicity are in agreement with those described in the literatura; (2) the detrimental effect obeyed the decreasing order - Mn Al CI; (3) dry matter production by the variety UFV - 1 was relatively more affected by the treatments; (4) leaf analyses do not provide a reliable indication of the sensitivity of the two varieties to the high levels of the three elements in the substrate; (5) Ca/Al ratio in the roots keeps a good relationship with the relative tolerance of the two cultivas to excess Al in the medium.Dois cultivares de soja, Santa Rosa e UFV-1, foram cultivados em solução nutritiva na presença de excesso de alumínio, cloro e manganês. Além de provocar o aparecimento de sintomas foliares (cloro e manganês) ou radiculares (alumínio), os elementos em excesso causaram diminuições no crescimento e impediram a produção de vagens. A análise mineral das folhas mostrou a influência dos tratamentos na composição do tecido
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