Multisite campaign on the open cluster M67 – III. δ Scuti pulsations in the blue stragglers

Bruntt, H.,Stello, D.,Suá,rez, J. C.,Arentoft, T.,Bedding, T. R.,Bouzid, M. Y.,Csubry, Z.,Dall, T. H.,Dind, Z. E.,Frandsen, S.,Gilliland, R. L.,Jacob, A. P.,Jensen, H. R.,Kang, Y. B.,Kim, S.-L. Blackwell Publishing Ltd 2007 MONTHLY NOTICES- ROYAL ASTRONOMICAL SOCIETY Vol.378 No.4

<P>ABSTRACT</P><P>We have made an asteroseismic analysis of the variable blue stragglers in the open cluster M67. The data set consists of photometric time-series from eight sites using nine 0.6–2.1 m telescopes with a time-baseline of 43 d. In two stars, EW Cnc and EX Cnc, we detect the highest number of frequencies (41 and 26) detected in δ Scuti stars belonging to a stellar cluster, and EW Cnc has the second highest number of frequencies detected in any δ Scuti star. We have computed a grid of pulsation models that take the effects of rotation into account. The distribution of observed and theoretical frequencies shows that in a wide frequency range a significant fraction of the radial and non-radial low-degree modes are excited to detectable amplitudes. Despite the large number of observed frequencies we cannot constrain the fundamental parameters of the stars. To make progress we need to identify the degrees of some of the modes from either multicolour photometry or spectroscopy.</P>

Emission-line activity in type 2 quasars from the Sloan Digital Sky Survey

Villar-Martí,n, M.,Humphrey, A.,Martí,nez-Sansigre, A.,Pé,rez-Torres, M.,Binette, L.,Zhang, X. G. Blackwell Publishing Ltd 2008 Monthly notices of the Royal Astronomical Society Vol.390 No.1

<P>ABSTRACT</P><P>We have compared the optical emission-line ratios of type 2 quasars from Zakamska et al. with standard active galactic nucleus (AGN) photoionization model predictions, type 2 Seyfert galaxies, H <SMALL>II</SMALL> galaxies and narrow-line Fanaro–Riley type II radio galaxies. Moderate to high-ionization narrow-line radio galaxies and type 2 Seyfert galaxies are indistinguishable from type 2 quasars based on their optical line ratios. The standard AGN photoionization models, widely discussed for other type 2 AGN, can reproduce successfully the loci and trends of type 2 quasars in some of the main diagnostic diagrams. These models are not exempt of problems, and the discrepancies with the data are the same encountered for other type 2 AGN. As for these, realistic models must take into account a range of cloud properties, as widely demonstrated in the literature.</P><P>The Zakamska et al. sample is strongly biased towards objects with high line luminosities (L[O <SMALL>III</SMALL>] >10<SUP>42</SUP> erg s<SUP>−1</SUP>). We have found that stellar photoionization is obvious in a fraction of objects (3 out of 50) which are characterized by low [O <SMALL>III</SMALL>] luminosities compared with most type 2 quasars in the sample. We suggest that if the sample were expanded towards lower line luminosities (∼10<SUP>40–42</SUP> erg s<SUP>−1</SUP>) stellar photoionization might be evident much more frequently.</P><P>We explore an alternative scenario to pure AGN photoionization in which a varying contribution of stellar ionized gas contributes to the line fluxes. Although the models presented here are rather simplistic and not strong quantitative results can be extracted regarding the relative contribution of stellar versus AGN photoionization, our results suggest that adding a varying contribution of stellar photoionized gas works in the right direction to solve most of the problems affecting the standard AGN photoionization models. The ‘temperature problem’ on the other hand remains.</P>

Assistive Technologies for Supporting Elderly People at Home: Telegerontology?

P. Su?rez,J. C. Mill?n-Calenti,A. L?pez-Vilar?n,I. Gonz?lez-Abraldes,M. Villanueva-Sampayo,A. Maseda 한국노년학연구회 2010 한국 노년학연구 Vol.19 No.-

The aging of the population worldwide implies an increase in the number of cognitive impairment associated diseases in the elderly. On the other hand, the number of informal caregivers is decreasing and consequently, we must guarantee the existence of enough social and health services for all the population in the immediate future. The new technologies allow us the development of more advanced instruments for gerontological intervention for both patients and caregivers. These new systems help to prevent the lack of home assistance, and thanks to the Internet connection, we avoid the disadvantages of the geographic dispersion of the population. In this article, we describe Telegerontology?, a new home attention tool for patients and caregivers. It integrates different functionalities related to physical, cognitive and medical intervention it works like a family support thanks to the professionals/patients communication, and integrates an advanced emergency system within a domotic environment. This system improves the traditional telecare since it, actually, has more sophisticated services and a higher quality of home support.

Control of selectivity in the reduction of nitrate by shielding of Pd–Cu/C catalysts with AOT

A.M. Pérez-Coronado,L. Calvo,J.A. Baeza,J.J. Rodriguez,M.A. Gilarranz 한국공업화학회 2020 Journal of Industrial and Engineering Chemistry Vol.82 No.-

Catalytic chemical reduction of nitrate without generating harmful nitrite and ammonium is still achallenge limiting the application of this technology to the production of drinking water. In this work anew approach was proposed based on shielding of Pd active sites in PdCu catalysts by sodium bis-2-ethylhexyl sulphosuccinate (AOT). To study this concept and the interactions between PdCu and AOT,carbon-supported PdCu catalysts were prepared by microemulsion using AOT as surfactant, and byincipient wetness impregnation followed by exposure to AOT. All the catalysts based on AOT showedlower activity in nitrate reduction than those prepared by ordinary incipient wetness impregnation,however ammonium generation was prevented thanks to shielding of Pd active sites by AOT. Bimetalliccatalysts prepared by physically mixing Pd and Cu monometallic catalysts and exposure to AOT revealed alower activity in nitrate reduction, which was ascribed to the interference of AOT in the Pd–Cu redoxmechanism and lower hydrogen spillover. However, the catalysts maintained the ability to reduce nitritewith negligible production of ammonium, showing that shielding of Pd active sites can be an interestingapproach to avoid nitrite and ammonium formation in nitrate reduction, but a compromise betweenactivity and selectivity must be achieved.

Enhancing the Formation of the New Trigonal Polymorph in Isotactic Propene-1-Pentene Copolymers: Determination of the X-ray Crystallinity

Ernesto Pérez,María L. Cerrada,Rosario Benavente,José M. Gómez-Elvira 한국고분자학회 2011 Macromolecular Research Vol.19 No.11

A metallocene copolymer of isotactic propene and 1-pentene was subjected to different crystallization conditions with 13 mol% of 1-pentene counits, aiming to enhance the formation of a new trigonal modification of iPP. Since it was not possible to obtain a diffractogram for the amorphous sample of cPPe13 at room temperature,the X-ray crystallinity was determined using the profile of the molten polymer, extrapolated to room temperature according to the resulting temperature coefficients. The X-ray diffraction results indicate a very interesting polymorphism in this copolymer; when crystallized from solution, amazingly high degrees of crystallinity - as high as 65%- are obtained, and this value is similar to those obtained for the iPP homopolymer. Further, the enthalpy of melting for a 100% crystalline sample of the trigonal modification was estimated from those crystallinities and the actual enthalpies of melting.

Sonographic evaluation of fetal scrotum, testes and epididymis

( Álvaro López Soto ),( Jose Luis Meseguer González ),( María Velasco Martínez ),( Rocío López Pérez ),( Inmaculada Martínez Rivero ),( Mónica Lorente Fernández ),( Olivia García Izquierdo ),( Juan Pe 대한산부인과학회 2021 Obstetrics & Gynecology Science Vol.64 No.5

External male genitalia have rarely been evaluated on fetal ultrasound. Apart from visualization of the penis for fetal sex determination, there are no specific instructions or recommendations from scientific societies. This study aimed to review the current knowledge about prenatal diagnosis of the scrotum and internal structures, with discussion regarding technical aspects and clinical management. We conducted an article search in Medline, EMBASE, Scopus, Google Scholar, and Web of Science databases for studies in English or Spanish language that discussed prenatal scrotal pathologies. We identified 72 studies that met the inclusion criteria. Relevant data were grouped into sections of embryology, ultrasound, pathology, and prenatal diagnosis. The scrotum and internal structures show a wide range of pathologies, with varying degrees of prevalence and morbidity. Most of the reported cases have described incidental findings diagnosed via striking ultrasound signs. Studies discussing normative data or management are scarce.

Development and Evaluation of a Nutritional Smartphone Application for Making Smart and Healthy Choices in Grocery Shopping

Desiree López,Michelle Torres,Jammy Vélez,Jhensen Grullon,Edwin Negrón,Cynthia M. Pérez,Cristina Palacios 대한의료정보학회 2017 Healthcare Informatics Research Vol.23 No.1

Objectives: This study developed a smartphone nutritional application (app) for making smart and healthy choices when purchasing food in grocery stores and tested its feasibility, usability, satisfaction and acceptability. Methods: “MyNutriCart” was developed following the ADDIE (analysis, design, development, implementation, and evaluation) model. The goals of the app were to improve food selection when purchasing foods in the grocery stores based on a pre-defined budget, to improve dietary patterns based on the Dietary Guidelines for Americans, and to improve weight status. It was evaluated within a pilot randomized trial using a convenient sample of 26 overweight or obese adults aged 21–45 years for 8 weeks. Results: The developed app provided a grocery list of healthy foods to meet the individual requirements of all family members within a budget following the recommendations of the Dietary Guidelines for Americans. The average use of the app was 75% on each purchase and only 37% of the recommended products were purchased. The main reasons for not purchasing the recommended items were that participants did not like these (28.5%) and that the item was unavailable in the supermarket (24.3%). Over 50% of participants considered the app as feasible, usable, satisfactory, and acceptable (p < 0.05). Conclusions: “MyNutriCart” is the first available app for making smart and healthy choices when purchasing food in grocery stores. This app could be used as a tool to translate recommendations into a practical grocery list that meet the needs of a family within a budget.

The fibrogenic process and the unleashing of acute-on-chronic liver failure

Guillermo Nahúm López-Sánchez,Mayra Dóminguez-Pérez,Misael Uribe,Natalia Nuño-Lámbarri 대한간학회 2020 Clinical and Molecular Hepatology(대한간학회지) Vol.26 No.1

Acute-on-chronic liver failure (ACLF) is a life-threatening condition characterized by a rapid deterioration of previously well-compensated chronic liver diseases. One of the main obstacles in ACLF is the lack of knowledge of the pathogenesis and specific broad-spectrum treatments. An excessive systemic inflammatory response has been proposed to explain the pathogenesis of ACLF; this hypothesis involves stellate cells, which are implicated in many liver homeostatic functions that include vitamin A storage, regulation of sinusoidal blood flow, local inflammation, maintenance of the hepatocyte phenotype and extracellular matrix remodeling. However, when there is damage to the liver, these cells are the main target of the inflammatory stimulus, as a result, the secretion of the extracellular matrix is altered. Activated hepatic stellate cells raise the survival of neutrophils by the stimulation of granulocytes colonies and macrophages, which exacerbates liver inflammation and promotes damage to hepatocytes. Elevation of pathogen-associated molecular patterns is related to liver damage by different pathophysiological mechanisms of decompensation, showing ballooning degeneration and cell death with a predominance of cholestatic infection. Moreover, patients with ACLF present a marked elevation of C-reactive protein together with an elevation of the leukocyte count. Chronic liver disease is a complex pathological state with a heterogeneous pathophysiology in which genetic factors of the host and external triggers interact and culminate in hepatic insufficiency. The better understanding of such interactions should lead to a better comprehension of the disease and to the discovery of new treatment targets that will make acute decompensations preventable and even decrease mortality.

Wetting layer and size effects on the nonlinear optical properties of semi oblate and prolate Si0.7Ge0.3/Si quantum dots

Kria M.,Varsha,Farkous M.,Prasad V.,Dujardin F,Pérez L.M.,Laroze D.,Feddi E. 한국물리학회 2021 Current Applied Physics Vol.25 No.-

Semi oblate and semi prolate are among the most probable self-organized nanostructures shapes. The optoelectronic properties of such nanostructures are not just manipulated with the height and lateral size but also with the wetting layer element. The practical interest of derivatives of germanium and silicon has a great important role in optoelectronic devices. This study is a contribution to the analysis of linear and nonlinear optical properties of Si0.7Ge0.3/Si. In the framework of the effective mass approximation, we solve numerically the Schr¨odinger equation relative to one particle confined in Si0.7Ge0.3/Si semi prolate and semi oblate quantum dots by using the finite element method and by taking into consideration the effect of the wetting layer. The energy spectrum of the lowest states and the dipolar matrix for the fourth allowed transitions are determined and discussed. We also calculate the detailed optical properties, including absorption coefficients, refractive index changes, second and third harmonic generation as a function of the quantum dot sizes. We found that with the change in the size of prolate and oblate quantum dots, there is a shift in the resonance peaks for the absorption coefficient and refractive index. It is due to the modification in the energy levels with changing size. The study proves a redshift in the second harmonic generation and third harmonic generation coefficients with an increase in the height/radius of the oblate/prolate quantum dot, respectively. We also demonstrated the variation of wavefunction inside the quantum dot with the change in wetting layer thickness.

Gallibacterium elongation factor-Tu possesses amyloid-like protein characteristics, participates in cell adhesion, and is present in biofilms

Jaqueline López-Ochoa,J. Fernando Montes-García,Candelario Vázquez,Patricia Sánchez-Alonso,Victor M. Pérez-Márquez,Patrick J. Blackall,Sergio Vaca,Erasmo Negrete-Abascal 한국미생물학회 2017 The journal of microbiology Vol.55 No.9

Gallibacterium, which is a bacterial pathogen in chickens, can form biofilms. Amyloid proteins present in biofilms bind Congo red dye. The aim of this study was to characterize the cell-surface amyloid-like protein expressed in biofilms formed by Gallibacterium strains and determine the relationship between this protein and curli, which is an amyloid protein that is commonly expressed by members of the Enterobacteriaceae family. The presence of amyloid-like proteins in outer membrane protein samples from three strains of G. anatis and one strain of Gallibacterium genomospecies 2 was evaluated. A protein identified as elongation factor-Tu (EF-Tu) by mass spectrometric analysis and in silico analysis was obtained from the G. anatis strain F149T. This protein bound Congo red dye, cross-reacted with anti-curli polyclonal serum, exhibited polymerizing properties and was present in biofilms. This protein also reacted with pooled serum from chickens that were experimentally infected with G. anatis, indicating the in vivo immunogenicity of this protein. The recombinant EF-Tu purified protein, which was prepared from G. anatis 12656-12, polymerizes under in vitro conditions, forms filaments and interacts with fibronectin and fibrinogen, all of which suggest that this protein functions as an adhesin. In summary, EF-Tu from G. anatis presents amyloid characteristics, is present in biofilms and could be relevant for the pathogenesis of G. anatis.