GUTs and String-GUTs

We look for a connection between string theories and Grand Unified Theories (GUTs), with the aim to look for new insights in the existing four dimensional string-GUT problems. We argue that the construction of consistent string-GUT models could require the use of non canonical affine levels. We list the most common level values related to realistic GUTs.Comment: 8 pages, Latex file, no figures. Acepted for publication in Europhysics Letter

Star formation and AGN activity in the most luminous LINERs in the local universe

This work presents the properties of 42 objects in the group of the most luminous, highest star formation rate LINERs at z = 0.04 - 0.11. We obtained long-slit spectroscopy of the nuclear regions for all sources, and FIR data (Herschel and IRAS) for 13 of them. We measured emission line intensities, extinction, stellar populations, stellar masses, ages, AGN luminosities, and star-formation rates. We find considerable differences from other low-redshift LINERs, in terms of extinction, and general similarity to star forming (SF) galaxies. We confirm the existence of such luminous LINERs in the local universe, after being previously detected at z ~ 0.3 by Tommasin et al. (2012). The median stellar mass of these LINERs corresponds to 6 - 7 $\times$ 10$^{10}$M$_{\odot}$ which was found in previous work to correspond to the peak of relative growth rate of stellar populations and therefore for the highest SFRs. Other LINERs although showing similar AGN luminosities have lower SFR. We find that most of these sources have LAGN ~ LSF suggesting co-evolution of black hole and stellar mass. In general among local LINERs being on the main-sequence of SF galaxies is related to their AGN luminosity.Comment: submitted to MNRA

Estudio comparativo, cruzado, doble ciego, al azar para determinar la bioequivalencia entre dos formulaciones de valsartán en tabletas y cápsulas

Introduction: Bioequivalence or compared equivalence studies are used to demonstrate claims that the new product, named generic product, will have the same bioavailability as the reference product, named brand product. If two products are bioequivalent it means that they would expect to have the same efficacy and security. Bioequivalence is established by the statistical estimation of significant differences or not in the pharmacokinetics parameters of area under the curve (AUC) and maximum concentration (Cmax). In this case, bioequivalence will be evaluated and the bioavailability of Valsartan will be compared. Valsartan is an agent antihypertensive and specific angiotensin II antagonist acting on the AT1 receptor subtype. Objective: The aim of this study was to evaluate the bioequivalence of two pharmaceutical products whose active principle is Valsartan, based on the comparison of the pharmacokinetic measures of rate and extent (in terms of required time) in which valsartan reaches the sanguineous circulation after a oral dose to 15 volunteers. Metodology: This was a randomized crossover double blind single-dose study on 15 male healthy volunteers aged between 19 and 28 years. The study was performed in two periods. Each treatment period consisted of a single-dose of 320 mg valsartan, with a wash-out time of 8 days between the first and second period. Plasma concentrations of valsartan were evaluated by HPLC/ UV with method of addition of valsartan standard and losartan as internal standard. Results: Valsartan tablets formulation showed this pharmacokinetic parameters: AUC 44,893 μg/mlxh, Cmax 6,430.3 μg/ml and Tmax 2 h. Valsartan capsules formulation showed this pharmacokinetic parameters: AUC 44,963 μg/mlxh, Cmax 5,831.4 μg/ml and Tmax 2.5 h. Conclusion: The study showed no statistically significant differences in the plasma concentration levels after administration of the two formulations of valsartan: 80 mg tablets and 80 mg capsules. So, the design of the study and the application of the protocols chosen enabled the demonstration of bioequivalence between the products. Introducción: Los estudios de bioequivalencia o equivalencia comparada se realizan para demostrar que el producto en estudio, conocido como producto genérico, tiene la misma biodisponibilidad del producto de referencia, también conocido como producto innovador o de marca. Si los dos productos son bioequivalentes, se espera que tengan las mismas características de seguridad y eficacia. La bioequivalencia es establecida por la estimación estadística de diferencias significativas o no en los parámetros farmacocinéticos de área bajo la curva (ABC) y concentración máxima (Cmáx). En este caso, se evaluará y se comparará la biodisponibilidad de valsartán, un agente antihipertensivo inhibidor específico del receptor de angiotensina II subtipo AT1, en las membranas celulares del músculo liso vascular. Objetivo: Evaluar la bioequivalencia de dos productos farmacéuticos cuyo principio activo es valsartán, con base en la comparación de las medidas farmacocinéticas de cantidad y velocidad (en términos de tiempo requerido), con que el valsartán alcanza la circulación sanguínea después de ser administrado por vía oral a 15 voluntarios. Metodología: Se realizó un estudio aleatorizado, cruzado, a doble ciego, de dosis única en 15 voluntarios sanos con edades entre 19 y 28 años. El estudio se realizó en dos períodos; en cada período de tratamiento se administró una dosis de 320 mg de valsartán, con un período de lavado de 8 días entre el primero y segundo tratamiento. Las concentraciones plasmáticas se evaluaron por HPLC/UV con el método de adición de estándar, empleando losartán como estándar interno. Resultados: Para las tabletas de valsartán se obtuvieron los siguientes parámetros farmacocinéticas: ABC de 44,893 μg/ mlxh, Cmáx de 6,430.3 μg/ml y Tmáx de 2 h. Para las cápsulas de valsartán se obtuvieron los siguientes parámetros farmacocinéticas: ABC de 44,963 μg/mlxh, Cmáx de 5,831.4 μg/ml y Tmáx de 2.5 h. Conclusión: Los resultados del estudio no mostraron diferencias significativas en los niveles de concentraciones plasmáticas después de la administración de las dos formulaciones de valsartán: 80 mg tabletas y 80 mg cápsulas. Por tanto, el diseño del estudio y la aplicación de los protocolos escogidos permitieron demostrar la bioequivalencia entre los productos

Geometry of CMC surfaces of finite index

Research of both authors was partially supported by MINECO/MICINN/FEDER grant no. PID2020-117868GB-I00, regional grants P18-FR-4049 and A-FQM-139-UGR18, and by the "Mariade Maeztu" Excellence Unit IMAG, reference CEX2020-001105-M, funded by MCINN/AEI/10.13039/501100011033/CEX2020-001105-M.Given r(0) > 0, I is an element of Nu boolean OR {0}, and K-0, H-0 >= 0, let X be a complete Riemannian 3-manifold with injectivity radius Inj(X) >= r(0) and with the supremum of absolute sectional curvature at most K-0, and let M (sic) X be a complete immersed surface of constant mean curvature H is an element of [0, H-0] and with index at most I. We will obtain geometric estimates for such an M (sic) X as a consequence of the hierarchy structure theorem. The hierarchy structure theorem (Theorem 2.2) will be applied to understand global properties of M (sic) X, especially results related to the area and diameter of M. By item E of Theorem 2.2, the area of such a noncompact M (sic) X is infinite. We will improve this area result by proving the following when M is connected; here, g(M) denotes the genus of the orientable cover of M: (1) There exists C-1 = C-1(I, r(0), K-0, H-0) > 0, such that Area(M) >= C-1(g(M) + 1). (2) There exist C 0 >, G (I) is an element of Nu independent of r(0), K-0, H-0, and also C independent of I such that if g(M) >= G(I), then Area (M) >= C/(max{1,1/r(0),root K-0, H-0})(2) (g(M) + 1). (3) If the scalar curvature rho of X satisfies 3H(2) +1/2 rho >= c in X for some c > 0, then there exist A, D > 0 depending on c, r(0), K-0, H-0 such that Area(M) <= A and Diameter(M) <= D. Hence, M is compact and, by item 1, g(M) <= A/C-1 - 1.MINECO/MICINN/FEDER PID2020-117868GB-I00"Mariade Maeztu" Excellence Unit IMAG - MCINN/AEI CEX2020-001105-MP18-FR-4049, A-FQM-139-UGR1

An [SU(3)]4 supersymmetric grand unified model

ABSTRACT: We present a grand unified model based on the supersymmetric SU(3)L⊗SU(3)CL⊗SU(3)CR⊗SU(3)R gauge group, which unifies in one single step the three gauge couplings of the standard model at an scale M∼1018 GeV, and spontaneously breaks down to SU(3)c⊗U(1)EM using only fundamental representations of SU(3). In this model the proton decay is highly suppressed and the doublet-triplet problem is lessened. The see-saw mechanism for the neutrinos is readily implemented with the use of an extra tiny mass sterile neutral particle for each generation which provides a natural explanation to the neutrino puzzle

Hierarchy structures in finite index CMC surfaces

William H. Meeks, III was partially supported by CNPq, Brazil, grant no. 400966/2014-0. Research of both authors was partially supported by MINECO/MICINN/FEDER grant nos. PID2020-117868GB-I00 and CEX2020-001105-M, both funded by MCINN/AEI, and by regional grant no. P18-FR-4049 funded by Junta de Andalucia.Given epsilon(0) > 0, I is an element of N boolean OR {0} and K 0, H 0 >= 0, let X be a complete Riemannian 3-manifold with injectivity radius Inj(X) = e 0 and with the supremum of absolute sectional curvature at most K-0, and let M (sic) X be a complete immersed surface of constant mean curvature H is an element of [ 0, H-0] with index at most I. For such M (sic) X, we prove a structure theorem which describes how the interesting ambient geometry of the immersion is organized locally around at most I points of M, where the norm of the second fundamental form takes on large local maximum values.Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPQ) 400966/2014-0MINECO/MICINN/FEDER: PID2020-117868GB-I00, CEX2020-001105-MMCINN/AEIJunta de Andalucía P18-FR-404

CO2 methanation over Ni-Al LDH-derived catalyst with variable Ni/Al ratio

CO2 methanation is a promising technology to recycle CO2 into useful chemicals, fuels, and energy, avoiding its emissions in the atmosphere, as well as for the purification of H2 streams containing CO2. In this work, Ni-Al LDH-derived catalysts with Ni/Al ratio between 0.5 and 4 were prepared by co-precipitation and evaluated in CO2 methanation. The samples were characterized by N2 physisorption, X-ray diffraction, temperature-programed reduction, temperature-programmed desorption (CO2-TPD, H2-TPD) and oxidation. Catalytic tests were carried out in a fixed-bed reactor at atmospheric pressure, inlet mixture of H2:CO2:N2 = 4:1:15 and GHSV = 60000 mL (gcat h)−1, in stepwise mode (200–400 °C) and stability at 300 °C. The catalysts presented high activity and selectivity, reaching 92.3 % of CO2 conversion at 300 °C, along with 100 % CH4 selectivity for the catalyst with NiAl = 2 due to its high number of weak-to-medium strength basic sites. The amount of H2-chemisorbed was higher for NiAl = 1, whereas the highest number of basic sites was for NiAl = 2. These results indicate that LDH-derived Ni-Al catalysts with a Ni/Al ratio between 1 and 2 would be suitable for CO2 methanation