Observation of magnetic order in the double-layer system La2MCu2O6+δ (M=Ca,Sr)

Under the terms of the Creative Commons Attribution License 3.0 (CC-BY).-- et al.Measurements of the spin rotation and depolarization of implanted positive muons have revealed that La2SrCu2O6+δ, La2CaCu2O6+δ, and La1.9Y0.1CaCu2O6+δ, members of the double-layer perovskite family La2MCu2O6+δ (M=Ca,Sr), display magnetic ordering similar to that of La2−xSrxCuO4−y and YBa2Cu3Ox Their magnetic order parameters are remarkably close to those of the other layered cuprates. A superconducting minority phase has been detected in La2CaCu2O6+δ (δ≥0.02), with onset at ∼45 K and accompanied by a change in the muon-spin-precession signals from the majority antiferromagnetic phase, phenomena absent in La2SrCu2O6+δ. This behavior was attributed to mobility and local clustering of intercalated oxygen excess in the layer between the CuO2 planes.This work was supported by NSERC (Canada), DOE Grant No. DE-FG05-88ER45353, the CICYT and the MIDAS project (Spain), and the CEE.Peer Reviewe

Diagnóstico del posgrado en México. Región Centro Occidente

El estudio tiene como propósito analizar la estructura institucional de la oferta del Posgrado en la Región Centro Occidente, con la finalidad de identificar fortalezas y debilidades y con ello proponer políticas públicas para el impulso de la calidad de los estudios de posgrado en México. Con base en la información nacional se elaboraron seis diagnósticos regionales y un diagnóstico nacional del posgrado. En este volumen se presentan los resultados de la Región Centro Occidente que incluye los estados Jalisco, Colima, Guanajuato, Nayarit, Michoacán y Aguascalientes. Se analizan las características de las Instituciones de Educación Superior que impactan en los posgrados que imparten, tales como origen de financiamiento, grado de desarrollo de su normativa, así como las formas de evaluación, entre otras. Se revisan las características académicas, administrativas y financieras de los programas de posgrado como niveles, orientación, modalidades, formación de competencias. Se da cuenta de las características de los actores del posgrado: estudiantes, coordinadores, egresados. Se presentan las relaciones de los posgrados con el entorno y se ofrece una sistematización y análisis cualitativo respecto a lo que los coordinadores identifican como problemas y perspectivas a futuro y estrategias de fortalecimiento del posgrado.Consejo Mexicano de Estudios de PosgradoConsejo Nacional de Ciencia y Tecnologí

Lack of replication of interactions between polymorphisms in rheumatoid arthritis susceptibility: case–control study

[Abstract] INTRODUCTION: Approximately 100 loci have been definitively associated with rheumatoid arthritis (RA) susceptibility. However, they explain only a fraction of RA heritability. Interactions between polymorphisms could explain part of the remaining heritability. Multiple interactions have been reported, but only the shared epitope (SE) × protein tyrosine phosphatase nonreceptor type 22 (PTPN22) interaction has been replicated convincingly. Two recent studies deserve attention because of their quality, including their replication in a second sample collection. In one of them, researchers identified interactions between PTPN22 and seven single-nucleotide polymorphisms (SNPs). The other showed interactions between the SE and the null genotype of glutathione S-transferase Mu 1 (GSTM1) in the anti-cyclic citrullinated peptide-positive (anti-CCP+) patients. In the present study, we aimed to replicate association with RA susceptibility of interactions described in these two high-quality studies. METHODS: A total of 1,744 patients with RA and 1,650 healthy controls of Spanish ancestry were studied. Polymorphisms were genotyped by single-base extension. SE genotypes of 736 patients were available from previous studies. Interaction analysis was done using multiple methods, including those originally reported and the most powerful methods described. RESULTS: Genotypes of one of the SNPs (rs4695888) failed quality control tests. The call rate for the other eight polymorphisms was 99.9%. The frequencies of the polymorphisms were similar in RA patients and controls, except for PTPN22 SNP. None of the interactions between PTPN22 SNPs and the six SNPs that met quality control tests was replicated as a significant interaction term--the originally reported finding--or with any of the other methods. Nor was the interaction between GSTM1 and the SE replicated as a departure from additivity in anti-CCP+ patients or with any of the other methods. CONCLUSIONS: None of the interactions tested were replicated in spite of sufficient power and assessment with different assays. These negative results indicate that whether interactions are significant contributors to RA susceptibility remains unknown and that strict standards need to be applied to claim that an interaction exists.Instituto de Salud Carlos III; 11/01048Instituto de Salud Carlos III; 12/01909Instituto de Salud Carlos III; RD12/0009/000

Scientific output on transsexuality in the Spanish biomedical literature: Bibliometric and content analysis (1973-2011)

Objetivo: Explorar la evolución del conocimiento científico sobre transexualidad durante los últimos 40 años, a través de un análisis bibliométrico y de contenido de la producción de la literatura biomédica española sobre la transexualidad entre los años 1973 y 2011. Método: Descriptivo y transversal. Universo: artículos biomédicos españoles sobre transexualidad publicados entre 1973 y 2011. Fuente: ÍndiceMédico Español e ISOC-Ciencias Sociales y Humanidades. Análisis: bibliométrico y de contenido de las publicaciones biomédicas. Resultados: 65 artículos biomédicos analizados. Entre 1973 y 1984, en España, el conocimiento sobre transexualidad se produce y circula en revistas médicas. En 1996 se inicia una década de gran productividad, y en los años siguientes el número de revistas que publican sobre transexualidad se multiplica. Hasta 2006, año de mayor productividad biomédica, los discursos biomédicos reproducen representaciones de la transexualidad ancladas en el determinismo biológico. En el período 2008-2011, los y las profesionales incorporan teorías feministas y perspectivas sociales en sus discursos. Conclusiones: En el último cuarto del siglo xx, el discurso médico dominante ha considerado las manifestaciones de las personas transexuales desde una perspectiva biologicista que concibe la transexualidad como un error de correspondencia sexo/género. En los últimos años, la aparición de nuevas categorías de identidad y la reflexión desde posturas no esencialistas y normativas del género favorece la gestión clínica de la transexualidad.Objective: To explore the scientific output on transsexuality in the Spanish biomedical literature between 1973 and 2011, through bibliometric and content analyses. Methods: We carried out a descriptive, cross-sectional study of Spanish biomedical articles on transsexuality published between 1973 and 2011. The data sources consisted of Índice Médico Español and ISOC-Ciencias Sociales y Humanidades. Bibliometric and content analyses were performed. Results: A total of 65 papers were analyzed. Knowledge on transsexuality in Spain began to appear in medical journals between 1973 and 1984. A decade of intense productivity began in 1996 and the number of journals publishing articles on transsexuality multiplied in the following years. Until 2006, the year with the most biomedical productivity, biomedical discourses reproduced representations of transsexuality anchored in biological determinism. From 2008-2011, professionals writing on the topic incorporated feminist theories and social perspectives in their discourses. Conclusions: In the last quarter of the twentieth century, the dominant medical discourse considered manifestations of transsexual people from a biologist perspective that conceives transsexuality as a configuration mismatch between sex and gender. The emergence of new identity categories and medical reflection from non-essentialist and non-normative gender perspectives has improved the clinical management of transsexuality

Genetic diversity of HLA system in four populations from Baja California, Mexico: Mexicali, La Paz, Tijuana and rural Baja California

We studied HLA class I (HLA-A, -B) and class II (HLA-DRB1, -DQB1) alleles by PCR-SSP based typing in 250 Mexicans from the states of Baja California Norte and Baja California Sur living in Mexicali (N = 100), La Paz (N = 75), Tijuana (N = 25) and rural communities (N = 50) to obtain information regarding allelic and haplotypic frequencies. The most frequent haplotypes for the Baja California region include nine Native American and five European haplotypes. Admixture estimates revealed that the main genetic components are European (50.45 ± 1.84% by ML; 42.03% of European haplotypes) and Native American (43.72 ± 2.36% by ML; 40.24% of Native American haplotypes), while the African genetic component was less apparent (5.83 ± 0.98% by ML; 9.36% of African haplotypes)

Evaluación de un programa de control de la brucelosis bovina en hatos lecheros de Baja California

A program for control of bovine brucellosis in dairy herds belonging to the Asociacion Ganadera Local de Productores de Leche de Tijuana, Baja California, was assessed. A total of 144,938 blood samples were collected and analyzed between August of 1998 and December 2001. For Brucella abortus antibody detection, 8 % Bengal rose (Card Test) and the confirmatory Rivanol test were used. Taking into account the whole four years period, overall prevalence was 1.9 % with a confidence interval (CI) of 1.87 to 2.01, whereas annual prevalences (cases/1,000 animals) and their CIs were 2.6 % (2.43 to 2.79), 2.0 % (1.88 to 2.16), 1.8 % (1.75 to 2.03) and 1.4 % (1.28 to 1.51), for 1998, 1999, 2000 and 2001, respectively. Annual prevalences at the herd level (cases/10 herds) were 45.8 % (32.1 to 59.9), 35.4 % (22.9 to 49.6), 32.0 % (20.2 to 45.8) and 25.9 % (15.5 to 38.7) for 1998, 1999, 2000 and 2001, respectively. A linear association tendency (PSe evaluó un programa para el control de la brucelosis bovina en hatos lecheros de productores pertenecientes a la Asociación Ganadera Local de Productores del municipio de Tijuana, Baja California. Se analizaron un total de 144,938 muestras de sangre durante el período de agosto de 1998 a diciembre de 2001. Para la detección de anticuerpos contra Brucella abortus se utilizaron las pruebas de Rosa de bengala al 8 % y Rivanol. Considerando el periodo completo, la prevalencia promedio fue de 1.9 %, con un intervalo de confianza (IC) de 1.87 a 2.01, mientras que las prevalencias anuales (casos/1,000 animales) y sus IC fueron de 2.6 % (2.43 a 2.79), 2.0 % (1.88 a 2.16), 1.8 % (1.75 a 2.03) y 1.4 % (1.28 a 1.51) para los años de 1998 a 2001 respectivamente. Las prevalencias anuales para este mismo periodo a nivel hato (casos/10 hatos) fueron de 45.8 % (32.1 a 59.9), 35.5 % (22.9 a 49.6), 32.0 % (20.2 a 45.8) y 25.9 % (15.5 a 38.7). Se detectó una tendencia de asociación lineal (

Superconductivity and magnetic order in super-oxygenated La2MCu2O6+δ (M=Ca,Sr)

Measurements of the spin rotation and depolarization of implanted positive muons have revealed that La2SrCu2O6+δ and La2CaCu2O6+δ display magnetic ordering similar to that of La2−xSrxCuO4−y and YBa2Cu3Ox. A superconducting phase was detected in La2CaCu2O6+δ (δ ≥ 0.05), with onset at ∼ 45K and accompanied by a change in the muon spin precession signals from the majority antiferromagnetic phase, phenomena absent in La2SrCu2O6+δ. This behaviour was attributed to mobility and local clustering of intercalated oxygen excess in the layer between the CuO2 planes.Work suported by the NRC and NSERC of Canada, CICYT and the MIDAS project, Spain; and the USA-DOE.Peer Reviewe

Humoral Acute Rejection in a Kidney Transplant Recipient with Idiopathic Thrombocytopenic Purpura

A 47-year-old male was diagnosed with chronic kidney disease (CKD) in 2011; idiopathic thrombocytopenic purpura (ITP) was also diagnosed in 2011 refractory to medical treatment and finally treated with splenectomy (2017) without relapses since that date, 5 blood transfusions, and 4 platelet apheresis in 2017. Renal transplant from a living related donor (brother), ABO compatible, crossmatch were negative, sharing 1 haplotype. Donor-specific anti-HLA antibody was negative. Graft function was stable until the 5th day and graft biopsy on the 6th day; thrombotic microangiopathy (TMA), C4D negative and inflammatory infiltration of polymorphonuclear leukocytes inside peritubular capillary, and anti-MICA antibodies were positive. The treatment used were plasmapheresis, intravenous immunoglobulin, and rituximab. Serum creatinine began to decrease since the 14th day, and by day 33, post-RT graft function was restored

Oxygen excess and superconductivity at 45 K in La2CaCu2O6+y

Preparation of single-phase stoichiometric La2CaCu2O6+y from oxide precursors is reported along with high-resolution neutron powder diffraction studies. To date this is the only route that allows the stoichiometric phase to be obtained. An air-heated sample having y=0.0378(8) displays a transition onset at 45 K to diamagnetic susceptibility. Nevertheless, the maximum amount of superconducting phase inferred from these flux exclusion experiments is only 1% in volume. It is also found that the diamagnetic signal is not substantially modified by changing the annealing atmosphere at normal pressures. Neutron diffraction data show a high atomic ordering of La and Ca ions with a strong preference (75%) of Ca ions for sites eight-fold coordinated located between the Cu-O2 planes. The other 25% is occupied by La ions, around which the excess oxygen is located with partial occupancies, yielding a higher coordination number for some of these La ions. Comparison of this structure with that of the nonsuperconducting oxide La1.9Ca1.1Cu2O6+y, suggests that the observed small superconductivity islands are related to clustered oxygen excess intercalated between the two Cu-O2 planes, along with the La ions. The small overall concentration of defects observed here, and thus the small number of holes, is responsible for the absence of bulk superconductivity in La2CaCu2O6+y.This work has been supported by Grants from the Spanish CICYT, from the MIDAS Program and by the European Economic CommunityPeer Reviewe