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Phys Rev Lett ; 120(15): 152001, 2018 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-29756848


All lattice-QCD calculations of the hadronic-vacuum-polarization contribution to the muon's anomalous magnetic moment to date have been performed with degenerate up- and down-quark masses. Here we calculate directly the strong-isospin-breaking correction to a_{µ}^{HVP} for the first time with physical values of m_{u} and m_{d} and dynamical u, d, s, and c quarks, thereby removing this important source of systematic uncertainty. We obtain a relative shift to be applied to lattice-QCD results obtained with degenerate light-quark masses of δa_{µ}^{HVP,m_{u}≠m_{d}}=+1.5(7)%, in agreement with estimates from phenomenology.

Phys Rev Lett ; 115(15): 152002, 2015 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-26550717


The rare decay B→πℓ^{+}ℓ^{-} arises from b→d flavor-changing neutral currents and could be sensitive to physics beyond the standard model. Here, we present the first ab initio QCD calculation of the B→π tensor form factor f_{T}. Together with the vector and scalar form factors f_{+} and f_{0} from our companion work [J. A. Bailey et al., Phys. Rev. D 92, 014024 (2015)], these parametrize the hadronic contribution to B→π semileptonic decays in any extension of the standard model. We obtain the total branching ratio BR(B^{+}→π^{+}µ^{+}µ^{-})=20.4(2.1)×10^{-9} in the standard model, which is the most precise theoretical determination to date, and agrees with the recent measurement from the LHCb experiment [R. Aaij et al., J. High Energy Phys. 12 (2012) 125].

Partículas Elementares , Modelos Teóricos , Física Nuclear , Prótons
Phys Rev Lett ; 112(11): 112001, 2014 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-24702353


We calculate the kaon semileptonic form factor f+(0) from lattice QCD, working, for the first time, at the physical light-quark masses. We use gauge configurations generated by the MILC Collaboration with Nf = 2 + 1 + 1 flavors of sea quarks, which incorporate the effects of dynamical charm quarks as well as those of up, down, and strange. We employ data at three lattice spacings to extrapolate to the continuum limit. Our result, f+(0) = 0.9704(32), where the error is the total statistical plus systematic uncertainty added in quadrature, is the most precise determination to date. Combining our result with the latest experimental measurements of K semileptonic decays, one obtains the Cabibbo-Kobayashi-Maskawa matrix element |V(us)| = 0.22290(74)(52), where the first error is from f+(0) and the second one is from experiment. In the first-row test of Cabibbo-Kobayashi-Maskawa unitarity, the error stemming from |V(us)| is now comparable to that from |V(ud)|.

Phys Rev Lett ; 109(7): 071802, 2012 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-23006357


The semileptonic decay channel B→Dτν is sensitive to the presence of a scalar current, such as that mediated by a charged-Higgs boson. Recently, the BABAR experiment reported the first observation of the exclusive semileptonic decay B→Dτ(-)ν, finding an approximately 2σ disagreement with the standard-model prediction for the ratio R(D)=BR(B→Dτν)/BR(B→Dℓν), where ℓ = e,µ. We compute this ratio of branching fractions using hadronic form factors computed in unquenched lattice QCD and obtain R(D)=0.316(12)(7), where the errors are statistical and total systematic, respectively. This result is the first standard-model calculation of R(D) from ab initio full QCD. Its error is smaller than that of previous estimates, primarily due to the reduced uncertainty in the scalar form factor f(0)(q(2)). Our determination of R(D) is approximately 1σ higher than previous estimates and, thus, reduces the tension with experiment. We also compute R(D) in models with electrically charged scalar exchange, such as the type-II two-Higgs-doublet model. Once again, our result is consistent with, but approximately 1σ higher than, previous estimates for phenomenologically relevant values of the scalar coupling in the type-II model. As a by-product of our calculation, we also present the standard-model prediction for the longitudinal-polarization ratio P(L)(D)=0.325(4)(3).

Ars pharm ; 51(supl.2): 324-330, mayo 2010. ilus, graf
Artigo em Espanhol | IBECS | ID: ibc-88648


El estudio de las materias primas farmacéuticas y cosméticas de origen mineral, sus propiedades,métodos de investigación específicos, normas de obligado cumplimiento para el uso y otros nuevosámbitos y aplicaciones de carácter sanitario que se han ido abriendo con el desarrollo de la Ciencia yla Técnica durante las últimas décadas, ha sido una asignatura de obligada impartición en los estudiosde Farmacia hasta la implantación del Nuevo Grado auspiciado por la puesta en práctica del PlanBolonia.En esta Comunicación se relata la historia de la asignatura, sus diferentes denominaciones y profesoresque ha tenido; se analizan en detalle sus contenidos científicos actuales y sus retos futuros: Todo elloen el marco del papel jugado hasta el presente en la Facultad de Farmacia en la formación delfarmacéutico, y para componer una base científica y argumental, que permita analizar objetivamente lasituación actual y las perspectivas futuras(AU)

The study of pharmaceutical and cosmetic mineral raw materials, their properties, their specificresearch methods, regulating norms and test for their use, and other new applications for the humanhealth that have been opened during the last decades owing to the development of Science andTechnology, has been a obligatory subject of teaching in the Pharmacy studies of the GranadaUniversity until the implantation of the new studies of Grade promoted by the Bologna Process.This communication relates the history of the subject "Applied Geology to Pharmacy", their differentdenominations and Professors who have had, analyzes in detail the current scientific content and itsfuture lines of research and challenges. All these discussions in the context of the role that has playeduntil today in the Faculty of Pharmacy as in the training of pharmaceutics. And to compose a scientificbasis and line of thinking, which allows to objectively analyze the current situation and future of thesubject "Applied Geology to Pharmacy"(AU)

Humanos , Masculino , Feminino , Adulto , Geologia/educação , Educação em Farmácia/métodos , Indústria Cosmética , Tecnologia de Cosméticos , Educação em Farmácia/organização & administração , Educação em Farmácia/tendências , Ciências do Solo/métodos , Conhecimentos, Atitudes e Prática em Saúde , Cristalografia/métodos
Ars pharm ; 51(supl.2): 505-510, mayo 2010. tab
Artigo em Espanhol | IBECS | ID: ibc-88675


Dentro de los estudios que abarca la Licenciatura (futuro Grado) en Farmacia, cabe destacar el interés de la Hidrología Farmacéutica, materia que estudia las aguas mineromedicinales, su origen, propiedades y aplicaciones dentro del campo de la salud, así como los barros preparados con aguas mineromedicinales dotados de actividad terapéutica (peloides). Esta asignatura resulta de gran interés para los estudiantes, ya que en su temario se desarrollan algunos aspectos que el farmacéutico podrá poner en práctica en su futuro profesional(AU)

Within the current and the future Degree in Pharmacy studies, it should be emphasized the importance of Pharmaceutical Hydrology, a matter dealing with the mineromedicinal waters, their origin, properties and applications in health care, as well as the muds, prepared with mineromedicinal waters, exerting therapeutic activity (therapeutic muds or peloids). This subject is of great interest for the students, since its program includes some contents that pharmacists will be able to put into practice in their professional activity.In the last decades, the number of scientific papers on this topic has increased noticeably. The study of the natural and mineromedicinal waters and the muds, either as preventive elements or as materials with therapeutic and coadjutant activity, has aroused an enormous interest among both lay people and health-care professionals, due to the benefits that it brings for health. The pharmacist plays a relevant role in the knowledge of this type of therapies and its applications.In this paper, we describe the history of this subject and analyze its scientific contents, as well as the importance of being acquainted with its applications within the training of the future pharmacists(AU)

Humanos , Masculino , Feminino , Hidrologia/métodos , Águas Minerais/análise , Saúde Ambiental/educação , Educação em Farmácia/métodos , Água/análise , Educação em Farmácia/normas , Educação em Farmácia/tendências , Águas Termais/análise , Fontes Termais/química
Phys Rev Lett ; 104(2): 022001, 2010 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-20366587


By using the highly improved staggered quark formalism to handle charm, strange, and light valence quarks in full lattice QCD, and NRQCD to handle bottom valence quarks, we are able to determine accurately ratios of the B meson vector-pseudoscalar mass splittings, in particular, [m(B{c}{*})-m(B{c})]/[m(B{s}{*})-m(B{s})]. We find this ratio to be 1.15(15), showing the "light" quark mass dependence of this splitting to be very small. Hence we predict m(B{c}{*})=6.330(7)(2)(6) GeV, where the first two errors are from the lattice calculation and the third from existing experiment. This is the most accurate prediction of a gold-plated hadron mass from lattice QCD to date.

Trastor. adict. (Ed. impr.) ; 5(2): 58-74, abr. 2003. tab
Artigo em Es | IBECS | ID: ibc-30830


Objetivo: Estudio de un caso práctico de un usuario de un centro ambulatorio de atención a drogodependencias a través de los patrones funcionales de salud de M. Gordon desde el modelo de H. Peplau. Material y métodos: Se describe el modelo teórico de Peplau así como la valoración de enfermería según M. Gordon atendiendo a cada patrón y a su significado según la experiencia de las autoras. Resultados: Se presenta un caso práctico, estableciéndose la valoración de necesidad de cuidados, diagnóstico y actuaciones de enfermería, así como las estrategias utilizadas para la intervención. Conclusiones: Centrarse en un modelo y llevar a cabo el proceso de enfermería, contando con un registro de valoración riguroso, adaptado a la filosofía enfermera y al método científico, ayuda a la aplicación más estructurada, personalizada y adecuada de los cuidados de enfermería a las necesidades individuales de cada paciente/cliente. Practicar la relación interpersonal enfermerapaciente además de favorecer el desarrollo y progresión del cliente, ayuda a los profesionales a evolucionar y madurar como personas (AU)

Adulto , Masculino , Humanos , Transtornos Relacionados ao Uso de Substâncias/enfermagem , Relações Enfermeiro-Paciente , Cuidados de Enfermagem/métodos , Diagnóstico de Enfermagem/métodos , Centros de Tratamento de Abuso de Substâncias , Administração dos Cuidados ao Paciente/métodos , Dependência de Heroína/enfermagem
Ars pharm ; 43(1/2): 23-35, ene. 2002. ilus, tab
Artigo em En | IBECS | ID: ibc-23465


Se estudian con microscopía electrónica de barrido la morfología y la ultramicrofábrica de talcos pulverizados y de preparados comerciales de "polvos de talco", con el objeto de caracterizarlos para su aplicación Farmacéutica y Cosmética. Se encuentran partículas pequeñas, partículas grandes, agregados y agregados en "bolsa", con fábricas laminares concéntricas y planares, laminares en dominios y fábricas de agregados. Estas morfologías se adquieren con el proceso de molienda, como consecuencia de la estructura cristalina y de las propiedades físicas (como dureza y exfoliación) del talco. Se consideran idóneas para el uso tópico porque favorecen la aplicación sobre la piel y permiten la adsorción de exudados debido a la porosidad y frecuencia de intersticios (AU)

Humanos , Talco/química , Talco/análise , Microscopia Eletrônica de Varredura/métodos , Administração Tópica
Ann Pharm Fr ; 47(1): 33-41, 1989.
Artigo em Francês | MEDLINE | ID: mdl-2627101


A study has been carried out on the possible pharmaceutical use of spanish talcs following the normalized assays of the main european pharmacopoeia and other quantitative methods. Only the talc nr3, not processed, meets all the assays of pharmacopoeia. The samples 2 and 4 (crushed) exceed the highest tolerated content in chlorides. The talc 1 (also crushed) only meets the loss on drying. The measures of some of these assays by using quantitative methods lead to more correct results and even sometimes in opposition with those obtained by pharmacopoeia methods. The particle size estimated by shifting and sedimentation shows that the crushed talcs are silty, whereas the only talc not processed is sandy. Considering the medium sizes estimated by scanning microscopy, it can be said that the pulverization of the talcs 1, 2 and 4 is characteristic of a micronization.

Farmacopeias como Assunto , Talco/análise , Tamanho da Partícula , Espanha , Talco/normas
Ann Pharm Fr ; 47(2): 53-61, 1989.
Artigo em Francês | MEDLINE | ID: mdl-2610468


A study has been carried out on the possible pharmaceutical use of 4 spanish talcs by direct estimation of the mineral purity by means of X-ray diffraction techniques, chemical analysis and quantification of some physico-chemical properties. There is a high level of talc in the samples 2 and 4, except in the talc 1 and the talc 3, with a relatively high content of chlorides. Quartz, calcite, feldspar, smectite, inter-stratified phases, kaolinite, amphibole, muscovite and dolomite are other contaminating minerals. The negative effects of these minerals on the pharmaceutical use of the talc include changes in the physical properties (colour), in the chemical ones (contained in heavy metals) as well as in the physico-chemical ones (adsorption properties). The data concerning cation exchange capacity and total specific surface are slightly higher than those concerning the pure mineral, and this is due to the occurrence of some contaminating minerals.

Talco/análise , Química Farmacêutica , Cloretos/análise , Cloretos/classificação , Troca Iônica , Minerais/análise , Espanha , Talco/farmacologia