108 research outputs found

    Few layer 2D pnictogens (P & Sb) catalyze the alkylation of soft nucleophiles with esters

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    Group 15 elements in zero oxidation state (P, As, Sb and Bi), also called pnictogens, are rarely used in catalysis due to the difficulties associated in preparing well-structured and stable materials. Here, we report on the synthesis of highly exfoliated, few layer 2D phosphorene and antimonene in zero oxidation state, suspended in an ionic liquid, with the native atoms ready to interact with external reagents while avoiding aerobic or aqueous decomposition pathways, and on their use as efficient catalysts for the alkylation of nucleophiles with esters. The few layer pnictogen material circumvents the extremely harsh reaction conditions associated to previous superacid-catalyzed alkylations, by enabling an alternative mechanism on surface, protected from the water and air by the ionic liquid. These 2D catalysts allow the alkylation of a variety of acid-sensitive organic molecules and giving synthetic relevancy to the use of simple esters as alkylating agents

    Exfoliation of Alpha-Germanium: A Covalent Diamond-Like Structure

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    2D materials have opened a new field in materials science with outstanding scientific and technological impact. A largely explored route for the preparation of 2D materials is the exfoliation of layered crystals with weak forces between their layers. However, its application to covalent crystals remains elusive. Herein, a further step is taken by introducing the exfoliation of germanium, a narrow-bandgap semiconductor presenting a 3D diamond-like structure with strong covalent bonds. Pure α-germanium is exfoliated following a simple one-step procedure assisted by wet ball-milling, allowing gram-scale fabrication of high-quality layers with large lateral dimensions and nanometer thicknesses. The generated flakes are thoroughly characterized by different techniques, giving evidence that the new 2D material exhibits bandgaps that depend on both the crystallographic direction and the number of layers. Besides potential technological applications, this work is also of interest for the search of 2D materials with new properties

    Equality, Equity, and Diversity: Educational Solutions in the Basque Country

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    Public education is one of the greatest achievements of European countries during the twentieth century. While schooling systems neither exclusively form citizens, nor are they sufficient to alleviate all inequalities, education plays an increasingly important strategic role in relieving social problems and promoting the civic and ethical upbringing of our children. Researchers and professors at the UPV/EHU have had the privilege to design and implement important educational projects in conjunction with government of Autonomous Community of the Basque Country, which has the authority over education in its territory. This book presents the timely (in most cases since 2000) observations, research, and programs that have resulted from this cooperation. Our stress—in both our theoretical and analytical dimensions—has been on the importance of diversity, the promotion of social and human values, and respect for basic human rights. In addition, we describe the cooperation that must be fostered—and the various needs met—between all educational "agents": academic researchers, administrators, teachers, parents, and the community at large to promote equality and fairness in our society.This book was published with generous financial support from the Basque Government.Introduction: Alfonso Unceta and Concepción Medrano ? Part 1 Education in the Basque Country ? 1. Education Provision in the Basque Country by Alfonso Unceta and Andrés Davila ? 2. Addressing Basque Diversity in the Classroom: Measures to Avoid Excluding At-Risk Youth by Begoña Martínez Domínguez ? 3. Improving Social Interaction: Experimentally Validated Proposals for Psycho-educational Intervention by Maite Garaigodobil and Jone Aliri ? 4. Socialization to Prevent Gender Violence in the Basque Country by Maria José Alonso Olea, Aitor Gómez González, and Nekane Beloki Arizti ? 5. Resolution and Transformation of At-School Conflicts by Ramón Alzate Sáez de Heredia, Lucía Gorbeña, and Cristina Merino ? Part 2 Socioeducational Context in the Basque Country ? 6. Learning Communities: A Basque Egalitarian Educational Project by Maite Arandia Loroño, Isabel Martínez Domínguez, and Iñaki Santa Cruz Ayo ? 7. Migrants en Route: Community Socioeducational Action by Miguel Arriaga Landeta and Begoña Abad Miguélez ? 8. Educating from the Family: A Proposal to Connect Homes and Institutions by Enrique Arranz Freijo, Fernando Olabarrieta Artetxe, Juan Luis Martín Ayala ? 9. The Development of Values and the Media by Concepción Medrano, Ana Aierbe, and Juan Ignacio Martínez de Morentin ? Index ? List of Contributor

    Interaction of short modified peptides deriving from glycoprotein gp36 of feline immunodeficiency virus with phospholipid membranes

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    A tryptophan-rich octapeptide, C8 (Ac-Trp-Glu-Asp-Trp-Val-Gly-Trp-Ile-NH2), modelled on the membrane-proximal external region of the feline immunodeficiency virus (FIV) gp36 glycoprotein ectodomain, exhibits potent antiviral activity against FIV. A mechanism has been proposed by which the peptide, being positioned on the surface of the cell membrane, inhibits its fusion with the virus. In the present work, peptide–lipid interactions of C8 with dimyristoyl phosphatidylcholine liposomes are investigated using electron spin resonance spectroscopy of spin-labelled lipids. Three other peptides, obtained from modifications of C8, have also been investigated, in an attempt to clarify the essential molecular features of the interactions involving the tryptophan residues. The results show that C8 adsorbs strongly on the bilayer surface. Membrane binding requires not only the presence of the Trp residues in the sequence, but also their common orientation on one side of the peptide that is engendered by the WX2 WX2 W motif. Membrane interaction correlates closely with peptide antiviral activity, indicating that the membrane is essential in stabilizing the peptide conformation that will be able to inhibit viral infection

    A correlative biomarker study and integrative prognostic model in chemotherapy-naïve metastatic castration-resistant prostate cancer treated with enzalutamide

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    There is a considerable need to incorporate biomarkers of resistance to new antiandrogen agents in the management of castration-resistant prostate cancer (CRPC). We conducted a phase II trial of enzalutamide in first-line chemo-naïve asymptomatic or minimally symptomatic mCRPC and analyzed the prognostic value of TMPRSS2-ERG and other biomarkers, including circulating tumor cells (CTCs), androgen receptor splice variant (AR-V7) in CTCs and plasma Androgen Receptor copy number gain (AR-gain). These biomarkers were correlated with treatment response and survival outcomes and developed a clinical-molecular prognostic model using penalized cox-proportional hazard model. This model was validated in an independent cohort. Ninety-eight patients were included. TMPRSS2-ERG fusion gene was detected in 32 patients with no differences observed in efficacy outcomes. CTC detection was associated with worse outcome and AR-V7 in CTCs was associated with increased rate of progression as best response. Plasma AR gain was strongly associated with an adverse outcome, with worse median prostate specific antigen (PSA)-PFS (4.2 vs. 14.7 m; p < 0.0001), rad-PFS (4.5 vs. 27.6 m; p < 0.0001), and OS (12.7 vs. 38.1 m; p < 0.0001). The clinical prognostic model developed in PREVAIL was validated (C-Index 0.70) and the addition of plasma AR (C-Index 0.79; p < 0.001) increased its prognostic ability. We generated a parsimonious model including alkaline phosphatase (ALP); PSA and AR gain (C-index 0.78) that was validated in an independent cohort. TMPRSS2-ERG detection did not correlate with differential activity of enzalutamide in first-line mCRPC. However, we observed that CTCs and plasma AR gain were the most relevant biomarkers

    Caso de Rabia canina importada de Marruecos a España. Junio de 2013.

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    El 5 de junio de 2013, el servicio de epidemiología de Castilla-La Mancha notificó al Centro de Coordinación de Alertas y Emergencias Sanitarias (CCAES) un caso confirmado de rabia en un perro abatido por la policía en la ciudad de Toledo el 1 de junio. El animal había mordido a cuatro niños y un adulto. Uno de los niños requirió hospitalización e ingresó en la Unidad de Cuidados Intensivos. El Laboratorio Nacional de Referencia para lyssavirus realizó el diagnóstico por inmunofluorescencia, PCR y cultivo celular, así como la secuenciación genómica de la cepa del virus y su comparación con las cepas circulantes en países endémicos. Inmediatamente tras conocerse los resultados, los cuatro niños y el adulto recibieron profilaxis post-exposición con vacuna e inmunoglobulina1 . Las investigaciones preliminares revelaron que el perro había viajado con sus dueños el 22 de mayo desde Cataluña a una pequeña localidad a 10 km de Toledo. Según los dueños, el perro había escapado unos días antes de ser localizado en Toledo. En ese momento existía la sospecha, aún sin confirmar, de que el perro hubiera estado unos meses antes en Marruecos. España (territorio peninsular, Islas Baleares y Canarias) ha estado libre de rabia terrestre desde 1978. Tras recibir la notificación y según lo establecido en el Plan de Contingencia para el control de la rabia en España2 , se constituyó una comisión técnica formada por representantes de la Dirección General de Salud Pública, Calidad e Innovación del Ministerio de Sanidad, Servicios Sociales e Igualdad (DGSPCI), la Dirección General de Sanidad de la Producción Agrícola y Ganadera del Ministerio de Agricultura, Alimentación y Medio Ambiente (DGSPA), las Comunidades Autónomas afectadas, el Laboratorio Nacional de Referencia de rabia y el Centro Nacional de Epidemiología (CNE). Los objetivos de esta comisión eran coordinar la investigación del suceso, evaluar el riesgo para la salud humana y animal, proponer la activación de los correspondientes niveles de alerta y coordinar la aplicación de las medidas de control apropiadas.N

    HIV-1 Tat immunization restores immune homeostasis and attacks the HAART-resistant blood HIV DNA: results of a randomized phase II exploratory clinical trial

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    Obesity Indexes and Total Mortality among Elderly Subjects at High Cardiovascular Risk: The PREDIMED Study

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    BackgroundDifferent indexes of regional adiposity have been proposed for identifying persons at higher risk of death. Studies specifically assessing these indexes in large cohorts are scarce. It would also be interesting to know whether a dietary intervention may counterbalance the adverse effects of adiposity on mortality.MethodsWe assessed the association of four different anthropometric indexes (waist-to-height ratio (WHtR), waist circumference (WC), body mass index (BMI) and height) with all-cause mortality in 7447 participants at high cardiovascular risk from the PREDIMED trial. Forty three percent of them were men (55 to 80 years) and 57% were women (60 to 80 years). All of them were initially free of cardiovascular disease. The recruitment took place in 11 recruiting centers between 2003 and 2009.ResultsAfter adjusting for age, sex, smoking, diabetes, hypertension, intervention group, family history of coronary heart disease, and leisure-time physical activity, WC and WHtR were found to be directly associated with a higher mortality after 4.8 years median follow-up. The multivariable-adjusted HRs for mortality of WHtR (cut-off points: 0.60, 0.65, 0.70) were 1.02 (0.78–1.34), 1.30 (0.97–1.75) and 1.55 (1.06–2.26). When we used WC (cut-off points: 100, 105 and 110 cm), the multivariable adjusted Hazard Ratios (HRs) for mortality were 1.18 (0.88–1.59), 1.02 (0.74–1.41) and 1.57 (1.19–2.08). In all analyses, BMI exhibited weaker associations with mortality than WC or WHtR. The direct association between WHtR and overall mortality was consistent within each of the three intervention arms of the trial.ConclusionsOur study adds further support to a stronger association of abdominal obesity than BMI with total mortality among elderly subjects at high risk of cardiovascular disease. We did not find evidence to support that the PREDIMED intervention was able to counterbalance the harmful effects of increased adiposity on total mortality.Trial RegistrationControlled-Trials.com ISRCTN3573963

    Original Article

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    The pancreas taken from the frog (Rana nigromaculata) was fixed in 1% OsO_4 and sliced into ultrathin sections for electron microscopic studies. The following observations were made: 1. A great \u27number of minute granules found in the cytoplasm of a pancreatic cell were called the microsomes, which were divided into two types, the C-microsome and S-microsome. 2. Electron microsopic studies of the ergastoplasm showed that it is composed of the microsome granules and A-substance. The microsomes were seen embedded in the A-substance which was either filamentous or membranous. The membranous structure, which was called the Am-membrane, was seen to form a sac, with a cavity of varying sizes, or to form a lamella. 3. The Am-membrane has close similarity to α-cytomembrane of Sjostrand, except that the latter is rough-surfaced. It was deduced that the Am-membrane, which is smooth-surfaced, might turn into the rough-surfaced α-cytomembrane. 4. There was the Golgi apparatus in the supranuclear region of a pancreatic cell. It consisted of the Golgi membrane, Golgi vacuole and. Golgi vesicle. 5. The mitochondria of a pancreatic cell appeared like long filaments, and some of them were seen to ramify. 6. The membrane of mitochondria, i. e. the limiting membrane, consisted of the Ammembrane. The mitochondria contained a lot of A-substances, as well as the C-microsomes and S-microsomes. When the mitochondria came into being, there appeared inside them chains of granules, which appeared like strips of beads, as the outgrowths of the A-substance and the microsome granules attached to the Am-membrane. They are the so-called cristae mitochondriales. 7. The secretory granules originate in the microsomes. They came into being when the microsomes gradually thickened and grew in size as various substances became adhered to them. Some of the secretory granules were covered with a membrane and appeared like what they have called the intracisternal granule of Palade.It seemed that this was a phenomenon attendant upon the dissolution and liqutefaction of the secretory granule. 8. Comparative studies were made of the ergastoplasm of the pancreatic cells from the frogs in hibernation, the frogs artificially hungered, the frogs which were given food after a certain period of fasting, the frogs to which pilocarpine was given subcutaneously, and the very young, immature frogs. The studies revealed that the ergastoplasm of the pancreatic cells greatly varied in form with the difference in nutritive condition and with different developmental stages of the cell. The change in form and structure occured as a result of transformation of the microsomes and A-substance. The ergastoplasm, even after it has come into being, might easily be inactivated if nutrition is defective. The ergastoplasm is concerned in the secretory mechanism, which is different from the secretory phenomenon of the secretory granules. It would seem that structurally the mitochondria have no direct relation to this mechanism

    The Eurasian Modern Pollen Database (EMPD), version 2

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    The Eurasian (née European) Modern Pollen Database (EMPD) was established in 2013 to provide a public database of high-quality modern pollen surface samples to help support studies of past climate, land cover, and land use using fossil pollen. The EMPD is part of, and complementary to, the European Pollen Database (EPD) which contains data on fossil pollen found in Late Quaternary sedimentary archives throughout the Eurasian region. The EPD is in turn part of the rapidly growing Neotoma database, which is now the primary home for global palaeoecological data. This paper describes version 2 of the EMPD in which the number of samples held in the database has been increased by 60 % from 4826 to 8134. Much of the improvement in data coverage has come from northern Asia, and the database has consequently been renamed the Eurasian Modern Pollen Database to reflect this geographical enlargement. The EMPD can be viewed online using a dedicated map-based viewer at https://empd2.github.io and downloaded in a variety of file formats at https://doi.pangaea.de/10.1594/PANGAEA.909130 (Chevalier et al., 2019)Swiss National Science Foundation | Ref. 200021_16959
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