THE UNAM-KIAS CATALOG OF ISOLATED GALAXIES

Herná,ndez-Toledo, H. M.,Vá,zquez-Mata, J. A.,Martí,nez-Vá,zquez, L. A.,Choi, Yun-Young,Park, Changbom American Institute of Physics 2010 The Astronomical journal Vol.139 No.6

<P>A new catalog of isolated galaxies from the Sloan Digital Sky Survey Data Release 5 (SDSS DR5) is presented. A total of 1520 isolated galaxies were found in 1.4 sr of sky. The selection criteria in this UNAM-KIAS catalog are a variation on the criteria developed by Karachentseva, including full redshift information. Through an image processing pipeline that takes advantage of the high-resolution (~0<img entity='farcs' SRC='http://ej.iop.org/icons/Entities/farcs.gif' ALT='farcs' ALIGN='BOTTOM' />4 pixel<SUP>–1</SUP>) and high dynamic range of the SDSS images, a uniform g-band morphological classification for all these galaxies is presented. We identify 80% (Sa-Sm) spirals (50% later than Sbc types) on one hand, and a scarce population of early-type E (6.5%) and S0 (8%) galaxies amounting to 14.5% on the other hand. This magnitude-limited catalog is ~80% complete at 16.5, 15.6, 15.2, 14.6, and 14.4 mag in the ugriz bands, respectively. Some representative physical properties including SDSS magnitudes and color distributions, color-color diagrams, absolute magnitude-color, and concentration-color diagrams as a function of morphological type are presented. The UNAM-KIAS Morphological Atlas is also released along with this paper. For each galaxy of a type later than Sa, a mosaic is presented that includes (1) a g-band logarithmic image, (2) a g-band filtered-enhanced image where a Gaussian kernel of various sizes was applied, and (3) a red giant branch color image from the SDSS database. For E/S0/Sa galaxies, in addition to the images in (1), (2), and (3), plots of r-band surface brightness and geometric profiles (ellipticity ε, position angle PA, and A<SUB>4</SUB>/B<SUB>4</SUB> coefficients of the Fourier series expansions of deviations of a pure ellipse) are provided. The size of the sample, the redshift completeness, the availability of high-quality multicolor photometric data and detailed morphological and spectroscopic information make the UNAM-KIAS catalog of isolated galaxies a suitable sample to address important issues such as (1) comparative studies of environmental effects, (2) constraining the currently competing scenarios of galaxy formation and evolution, (3) the nature and evolution of elliptical and spiral galaxies in the field, (4) the spectral properties of a statistically significant number of isolated galaxies and their evolution as a function of redshift, and (5) the fraction of active galactic nuclei in isolated environments, among other important topics. The optimization and estimation of new structural parameters as well as important information to complement existing ones in other wavelengths is being carried out.</P>

Effects of Semen Processing on Sperm Function: Differences between Swim-Up and Density Gradient Centrifugation

Hernández-Silva Gabriela,López-Torres Aideé S.,Maldonado-Rosas Israel,Mata-Martínez Esperanza,Larrea Fernando,Torres-Flores Víctor,Treviño Claudia L.,Chirinos Mayel 대한남성과학회 2021 The World Journal of Men's Health Vol.39 No.4

Purpose: Andrology research has evolved notoriously in the latest years, particularly since male factor contribution to couple infertility has been undoubtedly demonstrated. However, sperm function investigations results are sometimes contradictory, probably as a result of the use of different sperm processing techniques. In this work, we underwent a systematic functional comparison of human sperm samples simultaneously processed by swim-up and density gradient centrifugation, which are the preferred sperm processing methods used in basic and clinical laboratories. Materials and Methods: To compare functional characteristics of sperm isolated by swim-up and density gradient centrifugation followed by incubation at different times under capacitating conditions. Results: Semen samples processed in parallel by these two procedures resulted in sperm preparations with significant differences in redox state, spontaneous intracellular calcium oscillations, hyperactivation, protein tyrosine phosphorylation, and acrosome reaction responsivity to calcium ionophore. Such differences showed time-dependent specific patterns for spontaneous intracellular calcium oscillations, hyperactivation and protein tyrosine phosphorylation. Sperm retrieved by density gradient centrifugation showed more hyperactivation and tyrosine phosphorylation than swim-up sperm, suggesting a higher degree of capacitation. Conclusions: Our results account for functional differences observed in spermatozoa processed with these two methods and therefore may contribute to a better interpretation of outcomes obtained in different laboratories as well as to improve experimental designs aimed to study sperm physiology and fertility potential.

Pulse Classification for an Electrochemical Discharge Machining Process Based on Fuzzy Logic Approach

Ricardo Martínez-Alvarado,Everardo Efrén Granda-Gutiérrez,Alejandra Hernández-Rodríguez,Rolando Javier Praga-Alejo 한국정밀공학회 2020 International Journal of Precision Engineering and Vol.21 No.10

A pulse classification technique for monitoring the type of discharges in an electrochemical discharge machining (ECDM) process is presented in this research paper. The performance of an ECDM process is affected by many factors which make it hard for control strategies to be formulated for this process. The pulse classifier plays an important role to develop control strategies and later to improve the process. The proposed system uses the current and voltage waveforms measured through the gap as input signals for the classification system. A fuzzy inference system (FIS) is used to categorize both input signals into one of the four proposed pulse types, according to their specific behavior. For the experimental validation, data samples taken during the machining process were recorded to evaluate the performance of the pulse classifier with raw data. Raw data of the gap signals is properly classified based on the proposed FIS.

Development of Chemometric Models Using Infrared Spectroscopy (MID-FTIR) for Detection of Sulfathiazole and Oxytetracycline Residues in Honey

Karina Uribe Hernández,Tzayhrí Gallardo Velázquez,Guillermo Osorio Revilla,Norma Almaraz Abarca,Maylet Hernández Martínez 한국식품과학회 2015 Food Science and Biotechnology Vol.24 No.4

Chemometric models using mid-infrared (MID-FTIR) spectroscopy were developed for detection and quantification of oxytetracycline and sulfathiazole contamination in honey samples. Low standard error of calibration (SEC) and prediction (SEP) values were achieved using a partial least squares algorithm (SEC= 1.02 and SEP=1.39 for oxytetracycline and SEC=1.24 and SEP=1.79 for sulfathiazole). Chemometric model-predicted concentrations of antibiotics were compared with ELISA results with coefficient of determination R2=0.8577 for oxytetracycline and R2=0.8216 for sulfathiazole. Classification of antibiotic contaminated honey samples and uncontaminated samples was carried out using Soft Independent Modeling Class Analogy analysis with a 100% correct classification rate with interclass distances in the range of 6.93-13.3. MID-FTIR chemometric models developed for detection and quantification of oxitetracycline and sulfathiazole in honey samples have been demonstrated.

Artificial neural network based on genetic algorithm for emissions prediction of a SI gasoline engine

José D. Martínez-Morales,Elvia R. Palacios-Hernández,Gerardo A. Velázquez-Carrillo 대한기계학회 2014 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.28 No.6

This paper proposes a hybrid learning of artificial neural network (ANN) with the nondominated sorting genetic algorithm-II (NSGAII)to improve accuracy in order to predict the exhaust emissions of a four stroke spark ignition (SI) engine. In the proposed approach, thegenetic algorithm (GA) determines initial weights of local linear model tree (LOLIMOT) neural networks. A multi-objective optimizationproblem is determined. A sensitivity analysis is performed on NSGA-II parameters in order to provide better solutions along theoptimal Pareto front. Then, a fuzzy decision maker and the technique for order preference by similarity to ideal solution (TOPSIS) areemployed to select compromised solutions among the obtained Pareto solutions. The LOLIMOT-GA responses are compared with theprovided by radial basis function (RBF) and multilayer perceptron (MLP) neural networks in terms of correlation coefficient R².

Effect of Fucoidan Administration on Insulin Secretion and Insulin Resistance in Overweight or Obese Adults

Diana M. Hernández-Corona,Esperanza Martínez-Abundis,Manuel González-Ortiz 한국식품영양과학회 2014 Journal of medicinal food Vol.17 No.7

The aim of this article is to evaluate the effect of fucoidan administration on insulin secretion and insulin sensitivity in overweight or obese adults. A randomized, double-blind, placebo-controlled clinical trial was carried out in 25 obese or overweight volunteers. Thirteen patients received an oral dose of 500 mg of fucoidan once daily before breakfast and 12 patients received placebo for 3 months. Before and after the intervention, fasting glucose and 2-h postload, total cholesterol, high-density lipoprotein cholesterol, triglycerides, and insulin levels were measured. Low-density lipoprotein cholesterol (LDL-C) and homeostasis model analysis formulas (HOMA) for b-cell function and insulin resistance were calculated. The results showed a significant decrease in diastolic blood pressure (71.7 – 12.2 vs. 67.8 – 13.8 mmHg; P < .05) and LDL-C (3.1 – 0.5 vs. 2.7 – 0.6 mmol/l; P < .01) with increase in insulin levels (60.6 – 24.0 vs. 78.6 – 32.4 pmol/l; P < .05), HOMA b-cell (35.0 – 20.8 vs. 50.6 – 18.7; P < .05) and HOMA IR (1.9 – 1.2 vs. 2.6 – 1.8; P < .05) were observed after fucoidan administration. We conclude that fucoidan administration during a 3-month period in overweight or obese adults decreased diastolic blood pressure and LDL-C concentrations, increasing insulin secretion and insulin resistance.

MODELING ENGINE FUEL CONSUMPTION AND NOx WITH RBF NEURAL NETWORK AND MOPSO ALGORITHM

J. D. MARTÍNEZ-MORALES,E. R. PALACIOS-HERNÁNDEZ,G. A. VELÁZQUEZ-CARRILLO 한국자동차공학회 2015 International journal of automotive technology Vol.16 No.6

In this study, artificial neural network (ANN) modeling is used to predict the fuel consumption and NOx emission of a four stroke spark ignition (SI) engine. Calibration engineers frequently want to know the responses of an engine for the entire range of operating conditions in order to change engine control parameters in the electronic control unit (ECU), to improve performance and reduce emissions. However, testing the engine for the complete range of operating conditions is a very time and labor consuming task. As alternative, ANN is used in order to predict fuel consumption and NOx emission. In the proposed approach, the multi-objective particle swarm optimization (MOPSO) is used to determine weights of radial basis function (RBF) neural networks. The goal is to minimize performance criteria as root mean square error (RMSE) and model complexity. A sensitivity analysis is performed on MOPSO parameters in order to provide better solutions along the optimal Pareto front. In order to select a compromised solution among the obtained Pareto solutions, a fuzzy decision maker is employed. The correlation coefficient R2 is used to compare the engine responses with the obtained by the proposed approach.

Strength and Corrosion Studies of Mortars Added with Pozzolan in Sulphate Ions Environment

Roxana I. Martínez-Rosales,Juana María Miranda-Vidales,Lilia Narváez-Hernández,Juan Manuel Lozano de Poo 대한토목학회 2020 KSCE JOURNAL OF CIVIL ENGINEERING Vol.24 No.12

The pozzolanic materials have the capacity to modify the performance of Portland cement (PC) mortars. When they are used as supplementary materials, the physical-chemical properties such as compressive-strength and resistance to aggressive environments (chloride, sulphate, acids) are improved. In this article, a study was carried out to evaluate the effects of the addition of two natural pozzolans: volcanic pumice and zeolite. Both used as substitutes for PC in mortars based on cement, considering mechanical strength and the aggressive effect of sulphate ions. Furthermore, the electrochemical behavior of the steel rebar embedded in these mortars was studied during 730 days of exposition to aggressive conditions. The results revealed that the development of the compressive strength of mortars with pozzolans added reached similar values to the reference mortar. It was possible to observe that the addition of the pozzolan suppresses the ettringite formation proportionally to the pozzolan content. The corrosion resistance of the steel improves with the addition of pozzolans after 730 days of exposition at sulphate environment. The results of this study revealed the feasibility to use natural pozzolan as an additive during the preparation of cement up to 25% without significant changes of the physical-chemical properties of the mortars.

Curcumin-loaded Polycaprolactone/Collagen Composite Fibers as Potential Antibacterial Wound Dressing

E. San Martín-Martínez,Casañas-Pimentel,A. Almaguer-Flores,G. Prado-Prone,A. García-García,C. Landa-Solís,A. Hernández-Rangel 한국섬유공학회 2022 Fibers and polymers Vol.23 No.11

The development of wound dressings with therapeutical benefits is of great importance in skin tissue engineeringapplications, adding bioactive molecules into biomaterials is a strategy to achieve a better biological response. In this study,four different concentrations of curcumin (CUR; 5, 10, 15 and 20 by weight in relation to the PCL content) were incorporatedinto solutions composed of polycaprolactone (PCL) and collagen (COL) for the manufacture of electrospun fibers. The PCLCOL-CUR fibers were physicochemically characterized in terms of their morphology, wettability, degradation rate,mechanical behavior, and cumulative curcumin release. The in vitro biological properties of the composite membranes werealso evaluated. The results indicated that the membranes have diameters on average of approximately 200 nm. The wateruptake was adequate for exudates remotion in a wound, and the degradation rate of the fibers was highly appropriate toachieve complete skin tissue regeneration. The addition of CUR to composite membranes produced a significant increase inthe mechanical properties which indicate a satisfactory clinical handling. The incorporation of CUR produced a significantdecrease in the planktonic growth of S. aureus over time, however, the antibacterial effect against E. coli was limited, thepresence of CUR did not cause the inhibition of its growth. Finally, the viability of human dermal fibroblasts seeded on thetop of the membranes indicated the cytotoxic dosage effect of CUR, the two highest CUR concentrations produced asignificant loss of cell viability. Overall, our results suggested that the CUR-loaded PCL-COL composite membranes arepromising candidates for use as antibacterial dressings to enhance clinical wound management.

Mechanical Characterization of the Welding of Two Experimental HSLA Steels by Microhardness and Nanoindentation Tests

Edgar López-Martínez,Octavio Vázquez-Gómez,Héctor Javier Vergara-Hernández,Sergio Serna,Bernardo Campillo 대한금속·재료학회 2016 METALS AND MATERIALS International Vol.22 No.6

The microhardness and nanohardness of the welding zone of two experimental HSLA steels were determined. The first steel has a microstructure of martensite and bainite, and the second one has a microstructure of quasipolygonalferrite and acicular ferrite. In the bainitic - martensitic steel, softening of the heat affected zone wasobserved. This softening can be attributed to: the formation of polygonal ferrite in the recrystallization subzone,the formation of quasi-polygonal ferrite and the tempering of martensite in the intercritical subzone, andthe tempering of martensite in the subcritical subzone. Besides the softening, with nanoindentation technique, hardeningwas observed at the position where the peak temperature reached the critical temperature Ac1, which canbe attributed to a phenomenon of secondary hardening by precipitation of carbides of alloying elements. In theferritic steel, a softening phenomenon did not appear since there was no martensite in its initial microstructure. Finally, it was noted that both polygonal ferrite and the bainite have similar behavior and nanohardness, thiscoincidence can be attributed to the effect of grain boundary.