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influence of acid and alkaline sources on optical, structural and photovoltaic properties of CdSe nanoparticles precipitated from aqueous solution

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Frontiers of Materials Science 2016年第2期10卷 168-177页

作者： C. Selene CORiA-monroy Merida SOTELO-LERMA Hailin HU instituto de Energias Renovables Universidad Nacional Autonoma de Mexico (UNAM) Priv. Xochicalco S/N 62580 Temixco Morelos Mexico Universidad de Sonora Blvd. Luis Encinas y Rosales S/N Col. Centro Hermosillo Sonora Mexico

CdSe is a widely researched material for photovoltaic applications. One of the most important parameters of the synthesis is the pH value, since it determines the kinetics and the mechanism of the reaction and in consequence, the optical and morphological properties of the products. We present the synthesis of CdSe in solution with strict control of pH and the comparison of ammonia and KOH as alkaline sources and diluted HCi as acid medium. CdSe formation was monitored with photoluminescence emission spectra （main peak in 490 nm, bandgap of CdSe nanoparticles）. XRD patterns indicated that CdSe nanoparticles are mainly of cubic structure for ammonia and HCi, but the hexagonal planes appear with KOH. Product yield decreases with pH and also decreases with KOH at constant pH value since ammonia has a double function, as complexing agent and alkaline source. Changes in morphology were observed in SEM images as well with the different alkaline source. The effect of alkaline sources on photovoltaic performance of hybrid organic solar cells with CdSe and poly（3-hexylthio- phene） as active layers was clearly observed, indicating the importance of synthesis conditions on optoelectronic properties of promising semiconductor nanomaterials for solar cell applications.

关键词： CdSe optical properties morphological properties hybrid solar cells

Functional responses of cougars(Puma concolor)in a multiple prey-species system

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integrative Zoology 2018年第1期13卷 84-93页

作者： Leroy SORiA-DÍAZ Mike SFOWLER Octavio monroy-ViLCHiS Daniel ORO institute of Applied Ecology Autonomous University of TamaulipasVictoria city TamaulipasMexico Department of Biosciences Swansea UniversitySwanseaUK Center for Research in Applied Biological Sciences Autonomous University of the State of MexicoCentro TolucaMexico Population Ecology Group Mediterranean Institute for Advanced Studies IMEDEA(CSIC-UIB)EsporlesMallorcaSpain

The study of predator-prey interactions is commonly analyzed using functional responses to gain an understanding of predation patterns and the impact they have on prey *** this,little is known about predator-prey systems with multiple prey species in sites near the *** we studied the functional response of cougars(Puma concolor)in relation to their main prey,armadillo(Dasypus novemcinctus),coati(Nasua narica)and white-tailed deer(Odocoileus virginianus).Between 2004 and 2010,cougar scats were collected along 5 transects to estimate the consumption of different prey species.A relative abundance index(RAi)was calculated for each prey species and cougar using 18 camera *** compared Holling type i,ii and iii functional response models to determine patterns in prey consumption based on the relative abundance and biomass of each prey species *** 3 main prey species comprised 55%(armadillo),17%(coati)and 8%(white-tailed deer)of the *** i and ii functional responses described consumption of the 2 most common prey species armadillos and coati similarly well,while a type i response best characterized consumption of white-tailed deer.A negative correlation between the proportions of armadillo versus coati and white-tailed deer biomass in cougar scats suggests switching to consume alternative prey,confirming high foraging plasticity of this *** work represents one of the few studies to compare functional responses across multiple prey species,combined with evidence for prey-switching at low densities of preferred prey.

关键词： cougar functional responses Holling model comparison multiple prey

Control of tendon cell fate in the embryonic limb: A molecular perspective

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BiOCELL 2023年第3期47卷 465-471页

作者： JESSiCA CRiSTiNA MARÍN-LLERA CARLOS AMAURY JiMÉNEZ-CÁRDENAS JESÚS CHiMAL-monroy Departamento de Medicina Genómica y Toxicología Ambiental Instituto de Investigaciones BiomédicasUniversidad Nacional Autónoma de México Ciudad UniversitariaApartado Postal 70228MéxicoDF 04510México

The molecular cascade underlying tendon formation starts when progenitor cells begin to express the Scleraxis(Scx)*** knockout mice develop some but not all tendons,suggesting that additional factors are necessary for tendon commitment,maintenance,and *** transcription factors,such as Mohawk(Mkx)or early growth response(Egr),maintain Scx expression and extracellular matrix formation during *** inhibition of wingless and int-related protein signaling is necessary and sufficient to induce the expression of *** the commitment of tenogenic lineage occurs,transforming growth factor-beta(TGFβ)induces the Scx gene expression,becoming involved in the maintenance of tendon cell *** this point of view,we discussed two phases of the tenogenic process during limb development:dependent and independent of mechanical ***,we highlight the importance of understanding embryonic tendon development to improve therapeutic strategies in regenerative medicines for tendons.

关键词： Tendon differentiation Tenocyte Scleraxis Mohawk Early growth response Tendon development WNT TGFβ

isolation of Uranium by Anionic Exchange Resins

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Journal of Chemistry and Chemical Engineering 2016年第2期10卷 90-95页

作者： Fablola monroy-Guzman instituto Nacional de investigaciones Nucleares Carretera Mexico-Toluca S/N 52750 Mexico

A separation methodology to isolate natural uranium from its radioactive daughters： Th, Ra, Bi, Pb, Pa and Po, was developed using an only one anion exchange resin and varying concentrations of HC1 solutions. Three types of anion exchange resins were tested and the separation process was followed by gamma and alpha spectrometry. Uranium can be quantitatively isolated from its descendants using Dowex iX8 （20-50 mesh） or Amerlite iRA （100 mesh） resins in three steps： using 4 and 8 mol/L-1 HCi and water to recover uranium. The method is easy, quick, and inexpensive.

关键词： Anion exchange resin uranium separation.

The Tesistan, Mexico earthquake (M_w 4.9) of 11 May 2016: seismic-tectonic environment and resonance vulnerability on buildings

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Earthquake Engineering and Engineering Vibration 2019年第3期18卷 579-595页

作者： Alejandro Ramírez-Gaytán Adolfo Preciado William L. Bandy Edilson F. Salazar-monroy Miguel A. Jaimes Leonardo Alcantara Departamento de Ciencias Computacionales Centro Universitario de Ciencias Exactas e Ingeniería Universidad de Guadalajara Boulevard Marcelino García Barragán # 1421 44430 Guadalajara Jalisco México Departamento del Hábitat y Desarrollo Urbano Instituto Tecnológico y de Estudios Superiores de Occidente (ITESO). Periférico Sur Manuel Gómez Morin 8585 45604 Tlaquepaque Jalisco México instituto de Geofísica Universidad Nacional Autónoma de México Circuito Interior Ciudad Universitaria Del. Coyoacán 04510 México Programa de Posgrado en Ciencias de la Tierra Universidad Nacional Autó noma de Mé xico Circuito Interior Ciudad Universitaria Del. Coyoacá n 04510 Mé xico instituto de ingenieria Universidad Nacional Autónoma de México Circuito Interior Ciudad Universitaria Del. Coyoacán 04510 México

To highlight the importance of small earthquakes in seismic hazard, a study of the 11 May 2016, Mw 4.9, Tesistan, Mexico earthquake is presented. Due to the close proximity of the event to the city, accelerations were considerably higher than those caused by historical severe earthquakes (6.0 is paper addresses two objectives related to the Tesistan event: the fi rst is to estimate the focal mechanism solution in order to place the event in the context of the tectonic environment of this area. The second is focused on a vulnerability evaluation of buildings that suff ered resonance. Several building′s typologies with variations in construction system and height are assessed in terms of resonance with the structural and soil periods. The results show that around the Zapopan station, strong damage is expected in intermediate to high-rise buildings (12-30 m) with moment resistant frame systems and in reinforced concrete shear walls. Masonry structures around this station may not present resonance. in contrast, in the surroundings of the Guadalajara station, all intermediate height buildings from 9 to 21 m may present resonance.

关键词： Tesistan earthquake seismicity of Guadalajara site eff ects structural vulnerability

Mastoid obliteration and reconstruction techniques:A review of the literature

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Journal of Otology 2021年第3期16卷 178-184页

作者： Michelle Lupa Mendlovic Daniella Alejandra monroy Llaguno ivan Hermann Schobert Capetillo Juan Carlos Cisneros Lesser Otorhinolaryngology Resident Instituto Nacional de RehabilitacionMexico CityMexico Otorhinolaryngology Instituto Nacional de RehabilitacionMexico CityMexico Otorhinolaryngology and Neurotology Instituto Nacional de RehabilitacionMexico CityMexico

Objective To review the published literature related to the different obliteration and reconstruction techniques in the management of the canal wall down *** A PubMed(Medline)and LiLACS databases as well as crossed references search was performed with the following Mesh terms:“cholesteatoma”,“cholesteatoma-middle ear”,“otitis media”,“otitis media,suppurative”,“mastoiditis”,“mastoidectomy”,“canal wall down mastoidectomy”,“radical mastoidectomy”,“mastoid obliteration”and crossed *** criteria were adult patients subject to mastoid cavity obliteration and posterior canal wall *** technique and materials used,anatomic and functional results,complications,recurrence rates,and changes in quality of life,were analyzed.A total of 94 articles were screened,38 were included for full-text detailed *** Twenty-one articles fulfilled the inclusion *** and materials used for canal wall reconstruction,tympanoplasty,and ossiculoplasty were varied and included autologous,biosynthetic,or *** results were reported in 16 studies and were *** studies reported improvement in the quality of life using the GBi ***-up time ranged from 1 to 83 *** articles used imaging studies to evaluate postoperative disease *** highest recurrence rate reported for cholesteatoma after obliteration was 19%.The most frequently reported complications were retraction pockets and transient *** Plenty of techniques combining grafts and other materials have been used to overcome mastoidectomy cavity *** far,it is still not possible to standardize an ideal *** available level of evidence for this topic is low and limited.

关键词： Chronic otitis media Cholesteatoma Mastoidectomy Mastoid obliteration Quality of life

Experimental investigation of Transmission Properties and All-Optical Label Swapping of Orthogonal iM/FSK Labeled Signals

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光学学报 2003年第S1期23卷 679-680页

作者： Pablo V. Holm-Nielsen Christophe Peucheret idelfonso Tafur monroy Palle Jeppesen Research Center COM Technical University of Denmark 2800 Kgs. Lyngby DenmarkResearch Center COM Technical University of Denmark 2800 Kgs. Lyngby DenmarkCOBRA Research Institute Eindhoven University of Technology The NetherlandsResearch Center COM Technical University of Denmark 2800 Kgs. Lyngby Denmark

OpticallylabelediM/FSKsign***-optical label swapping based on MZ-SOA and EAM is presented. Transmission followed by label swapping shows a 2dB overall power penalty.

关键词： FSK on of iM Experimental investigation of Transmission Properties and All-Optical Label Swapping of Orthogonal iM/FSK Labeled Signals EAM SOA that into

Amphibian richness along modified riparian areas of central Mexico:conservation priorities

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Ecological Processes 2022年第1期11卷 902-915页

作者： Marco Tulio Oropeza‑Sánchez ireri Suazo‑Ortuño Julieta Benítez‑Malvido Erandi monroy‑Hernández Roberto Munguía‑Steyer instituto de investigaciones en Ecosistemas y Sustentabilidad(iiES) Universidad Nacional Autónoma de MéxicoAntigua Carretera a Pátzcuaro 8701CP 58190 MoreliaMichoacánMexico instituto de investigaciones Sobre los Recursos Naturales(iNiRENA) Universidad Michoacana de San Nicolás de HidalgoAv.San Juanito Itzícuaro S/NCP 58330 MoreliaMichoacánMexico Facultad de Estudios Superiores iztacala(FES‑iztacala) Universidad Nacional Autónoma de MéxicoAv.de los Barrios No.1CP 54090 Tlalnepantla de BazEstado de MéxicoMexico.

Background:Land‑use change frequently affects faunistic populations and *** achieve successful conservation strategies,we need suitable information about species distribution and the causes of extinction *** amphibian species depend on riparian vegetation to complete their life *** 41%of amphibian species are globally threatened,and accurate estimations of population size,species richness and the identification of critical habitats are urgently needed *** evaluate the magnitude of changes in species richness and demography,estimations that include detection probability are *** this study,we employed multi‑species occupancy models to estimate detection probability and the effect of land cover type(i.e.,cropland,artificial pasture,secondary and mature forest)in a 500‑m radius on the occupancy probability and richness of diurnal amphibians in 60 riparian zones in the state of Michoacán in central ***,we evaluated the potential of the endemic salamander Ambystoma ordinarium as a flagship species for the conservation of other native amphibian ***:We registered a total of 20 amphibian species in the diurnal assemblage,of which 10 species are considered at risk of *** found that cropland was the most important land‑use type for explaining amphibian distribu‑tion in riparian zones,with negative effects on most amphibian *** found no differences in species richness between zones with and without *** riparian zones occupied by ***,however,we found a higher number of species at risk of ***:Our findings showed negative effects of croplands on the distribution of most amphibian *** riparian zones are important for the maintenance of native diurnal amphibian communities and *** can act as a flagship species for the conservation of threatened amphibian species.

关键词： Flagship species Habitat quality Occupancy models Salamanders Threatened species

A Brief Tour on Exotic Control Objectives in Robotics

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Journal of Mechanics Engineering and Automation 2018年第2期8卷 53-59页

作者： Rafael Kelly Carmen monroy DET-DFA Division de Fisica Aplicada CICESE Carretera Ensenada-Tijuana No. 3918 Zona Playitas Ensenada B.C. 22860 Mexico iSEP-Sistema Educativo Estatal Zona 01 Ensenada B.C. 22800 Mexico

Formulation of control objectives is a key issue in automatic control systems design. Although at first sight the desired goal （control objective） of a control system seems to be a trivial and obvious matter, for effectiveness of some high level robotic tasks, unusual exotic control objectives may be required. This paper presents a review of some exotic control objectives useful in robotics, such as velocity field control objective and range control objective. The paper also proposes a novel confinement control objective. The usefulness of these exotic control objectives may appear in safe robot-human interaction and self-protection of robots against collisions.

关键词： Control objective robot robot-human confinement range velocity field TEFDA (total energy function with damping assignment) exotic.