1,384,215 research outputs found
Correspondencia de Francisco O. Arce sobre el caso Miguel López
No full textDeclaraciones hechas por el Gral. de Brigada, Francisco O. Arce sobre el caso del Coronel imperialista Miguel López, sobre si se reunió con el Emperador Maximiliano días antes y días después del 15 de mayo de 1867, para verificar las declaraciones hechas por Mariano Escobedo de que López no traicionó a Maximiliano, como se hizo creer en su momento.
Varias declaraciones, entre ellas la del General Joaquín M. Rangel, hecha\ua0a Arce el 20 de Julio de 1887.\ua0Otra de Carlos E. Margain redactada en Sonora el 31 de Julio de 1887</p
[Affidavit in Any Fact - Statement by Danny Garcia Arce, November 22, 1963 #1]
No full textTranscription of a statement by Danny Garcia Arce, an employee of the Texas School Depository Building, describing the events the day of the Kennedy Assassination
[Affidavit in Any Fact - Statement by Danny Garcia Arce, November 22, 1963 #2]
No full textTranscription of a statement by Danny Garcia Arce, an employee of the Texas School Depository Building, describing the events the day of the Kennedy Assassination
Arce Guerrero
No full textCarta del señor Arce Guerrero a Camilo Correa y respuesta de este último.Biblioteca Luis Echavarría Villegas, Sala de Patrimonio Documenta
Carta enviada por José Arce a Santiago Arroyo
No full textCarta enviada por José Arce a Santiago Pérez Valencia [Santiago Arroyo] sobre asuntos personales. Fechada en Santafé
Filtering efficiency model that includes the statistical randomness of non-woven fiber layers in facemasks
No full textFacemasks have become important tools to fight virus spread during the recent COVID-19 pandemic, but their effectiveness is still under debate. We present a computational model to predict the filtering efficiency of an N95-facemask, consisting of three non-woven fiber layers with different particle capturing mechanisms. Parameters such as fiber layer thickness, diameter distribution, and packing density are used to construct two-dimensional cross-sectional geometries. An essential and novel element is that the polydisperse fibers are positioned randomly within a simulation domain, and that the simulation is repeated with different random configurations. This strategy is thought to give a more realistic view of practical facemasks compared to existing analytical models that mostly assume homogeneous fiber beds of monodisperse fibers. The incompressible Navier-Stokes and continuity equations are used to solve the velocity field for various droplet-laden air inflow velocities. Droplet diameters are ranging from 10 nm to 1.0 μm, which covers the size range from the SARS-CoV-2 virus to the large virus-laden airborne droplets. Air inflow velocities varying between 0.1 m·s−1 to 10 m·s−1 are considered, which are typically encountered during expiratory events like breathing, talking, and coughing. The presented model elucidates the different capturing efficiencies (i.e., mechanical and electrostatic filtering) of droplets as a function of their diameter and air inflow velocity. Simulation results are compared to analytical models and particularly compare well with experimental results from literature. Our numerical approach will be helpful in finding new directions for anti-viral facemask optimization
Macrodactylus montanus Arce-Perez & Moron 2000
No full textMacrodactylus montanus Arce-Pérez & Morón, 2000 Figs. 20, 45–47, 86 Material examined. 37 specimens: 18 ♂, 19 ♀. Diagnosis. Body length 12–13 mm; integument of the body black; clypeus red, antennal flagellum, elytra, legs and, pygidium reddish yellow; dorsum and venter with thin, scattered pale yellow vestiture; tarsi with rings of short, white setae (Fig. 20); parameres circular, setose, with a narrow ridge on its internal margins, expanded into a welldeveloped distal shelf-like ledge, apices strongly lanceolate, lateral margins on distal half with sparse, mediumsized setae (Figs. 45–46). Female similar to male; genital plates (Fig. 47). Figures 48–56. Dorsal view of Macrodactylus. 48, Macrodactylus nigripes Bates; 49, M. rufescens Bates; 50, M. seiceicollis Bates; 51, M. sericinus Bates; 52, M. suavis Bate s; 53, M. sylphis Bates; 54, M. tibialis Arce-Pérez & Morón; 55, M. zaragozai Arce-Pérez & Morón; 56, M. zunilensis Bates. Natural history. This species inhabits temperate-cool or humid areas between 1,800 and 2,800 m (additional information in Arce-Pérez & Morón 2000, 2005, 2011). Geographical distribution. Mexico (Chiapas), El Salvador (Santa Ana), and Honduras (Ocotepeque, Lempira) (Fig. 86). Figures 57–83. Diagnostic estructures of male and female of Macrodactylus. Parameres, distal view; parameres, lateral view; genital plates, ventral view. 57–59, Macrodactylus nigripes Bates; 60–62, M. rufescens Bates; 63–65, M. seiceicollis Bates; 66–68, M. sericinus Bates; 69–71, M. suavis Bate s; 72–74, M. sylphis Bates; 75–77, M. tibialis Arce-Pérez & Morón; 78–80, M. zaragozai Arce-Pérez & Morón; 81–83, M. zunilensis Bates. Figure 84. Distribution of Macrodactylus in the Central American Nucleus: M. eniocanoi (yellow circle), M. escuintlaensis (blue circle), M. fulvescens (orange circle), M. hondurensis (purple circle), M. lineatocollis (red circle), M. sylphis (green circle), M. tibialis (pink circle). Figure 85. Distribution of Macrodactylus in the Central American Nucleus: M. carrilloi (yellow circle), M. costulatus (blue circle), M. championi (green circle), M. sericinus (red circle).Published as part of Arce-Pérez, Roberto & Morón, Miguel Ángel, 2020, Review of the species of Macrodactylus Dejean (Coleoptera: Scarabaeidae Melolonthinae) from the Central American Nucleus, pp. 567-584 in Zootaxa 4772 (3) on pages 575-578, DOI: 10.11646/zootaxa.4772.3.7, http://zenodo.org/record/381976
Overcoming Voltage Losses in Vanadium Redox Flow Batteries Using WO3 as a Positive Electrode
No full textVanadium redox flow batteries (VRFBs) are appealing large-scale energy storage systems due to their unique properties of independent energy/power design. The VRFBs stack design is crucial for technology deployment in power applications. Besides the design, the stack suffers from high voltage losses caused by the electrodes. The introduction of active sites into the electrode to facilitate the reaction kinetic is crucial in boosting the power rate of the VRFBs. Here, an O-rich layer has been applied onto structured graphite felt (GF) by depositing WO3 to increase the oxygen species content. The oxygen species are the active site during the positive reaction (VO2+/VO2+) in VRFB. The increased electrocatalytic activity is demonstrated by the monoclinic (m)-WO3/GF electrode that minimizes the voltage losses, yielding excellent performance results in terms of power density output and limiting current density (556 mWcm−2@800 mAcm−2). The results confirm that the m-WO3/GF electrode is a promising electrode for high-power in VRFBs, overcoming the performance-limiting issues in a positive half-reaction.Miguel A. Rodriguez-Olguin, Han Gardeniers, and Arturo Susarrey-Arce acknowledge the funding for their research received from the European Research Council (ERC) under the European Union's Horizon 2020 Research and Innovation Program (Grant agreement No. 742004). C. Flox acknowledges financial support from the Ministery of Science Spain, AEI Severo Ochoa Grant CEX2019-000917-S, and the European Commission under the grant MSCA-IF-EF-ST, proposal number 101026162.With funding from the Spanish government through the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000917-S).Peer reviewe
Exploiting Covalent, H-Bonding, and π-πInteractions to Design Antibacterial PDMS Interfaces That Load and Release Salicylic Acid
No full textSmart antimicrobial surfaces are a powerful tool to prevent bacterial colonization at surfaces. In this work, we report a successful strategy for the functionalization of polydimethylsiloxane (PDMS) surfaces, widely used in medical devices, with salicylic acid (SA), a biocide approved for use in humans. Antimicrobial PDMS surfaces were fabricated via a rational design in which bifunctional silane linker molecules were covalently grafted onto the PDMS via one end, while soft intermolecular interactions with SA were generated at the other end to enable reversible load and release of the biocide. A molecular level understanding of the interface was obtained using attenuated total reflectance Fourier transform infrared, Raman, and X-ray photoelectron spectroscopies, alongside density functional theory calculations. These reveal that the linker molecules dock the SA molecules at the surface via a 1:1 complexation interaction. Furthermore, each 1:1 complex acts as a nucleation point onto which multiple stacks of the biocide are subsequently stabilized via a combination of H-bonding and π-πstacking interactions, thus significantly enhancing SA uptake at the interface. The antimicrobial activity of these surfaces against model Gram-negative and Gram-positive bacteria represented by Escherichia coli, Staphylococcus aureus, and Staphylococcus epidermidis is demonstrated by a log 6 reduction of planktonic bacterial populations and an efficient anti-biofilm activity at the surface
Effect of Local Topography on Cell Division of Staphylococcus spp
No full textSurface engineering is a promising strategy to limit or prevent the formation of biofilms. The use of topographic cues to influence early stages of biofilm formationn has been explored, yet many fundamental questions remain unanswered. In this work, we develop a topological model supported by direct experimental evidence, which is able to explain the effect of local topography on the fate of bacterial micro-colonies of Staphylococcus spp. We demonstrate how topological memory at the single-cell level, characteristic of this genus of Gram-positive bacteria, can be exploited to influence the architecture of micro-colonies and the average number of surface anchoring points over nano-patterned surfaces, formed by vertically aligned silicon nanowire arrays that can be reliably produced on a commercial scale, providing an excellent platform to investigate the effect of topography on the early stages of Staphylococcus spp. colonisation. The surfaces are not intrinsically antimicrobial, yet they delivered a topography-based bacteriostatic effect and a significant disruption of the local morphology of micro-colonies at the surface. The insights from this work could open new avenues towards designed technologies for biofilm engineering and prevention, based on surface topography
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