bluuebunny/crossref_metadata_2025_split huggingface dataset:
ACUERDOS Y COMPROMISOS: FAMILIAS Y PROGRAMAS SOCIALES DESDE UNA MIRADA TEÓRICA
Authors: Picasso Risso Florencia 
Published: April 2017

El presente artículo procura contribuir a la reflexión teórica sobre los encuentros entre las familias beneficiarias y los programas sociales en el contexto latinoamericano. Se busca reflexionar cómo se produce la recepción de las políticas sociales, en relación a los sujetos vulnerados en sus derechos y qué sucede a partir de tales intervenciones. Desde esta premisa inicial vinculada a la tesis doctoral, parte el presente artículo que procura desarrollar una aproximación teórica a estas interrogantes, a la luz de la mirada de Habermas, Bourdieu y Berger y Luckmann. La reflexión despierta varias pistas teóricas atrayentes para tensionar las prácticas, expectativas, posibilidades e imposiciones, desde la lógica familiar-institucional-profesional y en el marco de la intervención de la política pública. En este sentido, resulta una tríada potente para abordar el objeto de estudio.
JÓVENES UNIVERSITARIOS: PERCEPCIONES Y ENCUESTAS SOBRE CONFLICTO ARMADO Y PAZ EN COLOMBIA
Authors: Wilches Tinjacá Jaime Andrés , Hernández Pérez Mauricio 
Published: April 2017

El artículo tiene como objetivo identificar los referentes conceptuales y las estrategias metodológicas que se han utilizado para dar cuenta de las reacciones de la sociedad civil, en torno al proceso de paz que se adelanta entre el gobierno de Juan Manuel Santos y las Fuerzas Armadas Revolucionarias de Colombia (FARC). Luego de realizado este rastreo se evidenció, que las encuestas asociadas a las percepciones son la estrategia privilegiada de centros de pensamiento, investigadores y medios de comunicación, para justificar sus perspectivas de análisis frente a una salida negociada del conflicto armado. De acuerdo a lo anterior, se formuló una propuesta metodológica encaminada a realizar una encuesta a quinientos jóvenes universitarios de instituciones de educación superior públicas y privadas.Los resultados evidenciaron que las preguntas asociadas a la bipolaridad guerra - paz son más fáciles de responder que las asociadas al reconocimiento de actores, discursos y estrategias que han incidido en la comprensión del enfrentamiento bélico en Colombia. Aún más complejo cuando se solicita proponer soluciones o ideas en un posible escenario de posconflicto. Por último, se proponen algunas consideraciones finales que invitan a construir estrategias pedagógicas que logren incidir en las personas jóvenes, como actores claves para movilizar prejuicios, desconocimientos e indiferencias en los retos que supone la construcción de paz.
Molecular Imprinting of Polymeric Core-Shell Nanoparticles
Authors: Moral Natalia Pérez , Mayes Andrew G. 
Published: April 2017

AbstractIn order to evaluate the compatibility of structured nanoparticles produced by aqueous emulsion polymerisation with the non-covalent imprinting procedure, a number of imprinted polymeric nanoparticles have been synthesised by seeded emulsion polymerisation in the presence and absence of a porogenic solvent. Propranolol was chosen as the template molecule using methacrylic acid (MAA) and ethylene glycol dimethacrylate (EDMA) as functional monomer and crosslinker respectively. The influence of the porogen and the amount of template added was studied by measuring the capacity of the polymeric particles to rebind template both in organic and aqueous buffers by radioligand binding assay. By increasing the amount of template from 0.5 to 6% (mol/mol with respect to monomers) the specific rebinding was increased from 2% to 24% in aqueous buffer and to 31% in a toluene based assay. The influence of the porosity was also established when the rebinding was performed in an organic solvent.
Oligonucleotide Imprinting in Aqueous Environment
Authors: Batra Dolly , Shea Kenneth J. 
Published: April 2017

AbstractThe development of synthetic receptors that recognize nucleotide bases and their derivatives is an important area of research [1-3]. Applications are envisioned in separation science, biosensors, drug therapy and genetic engineering. Previously in this laboratory, we have developed a molecularly imprinted synthetic receptor for 9-ethyladenine (9-EA). The network polymer has an affinity for adenine and its derivatives with an average association constant (Ka) of 75,000 M–1 in CHCl3 [4]. When a 9-EA imprinted polymer was used as the chromatographic support, adenine eluted at 27 minutes using 92.5/5/0/2.5 CH3CN/H2O/CH3CO2H as the mobile phase, while cytosine, guanine and thymine derivatives all eluted close to the void volume (2.0 min). In addition, imprinted polymers have been made with complementary binding sites for cytosine and guanine [5], as well as other nucleotide base analogues [6].The extension of these results to construct robust receptors for oligonucleotides requires fundamental changes in imprinting strategies. Most importantly, since oligonucleotides are water soluble, strategies that employ EGDMA/MAA formulations in organic solvents will need to be replaced with those that do not compromise the interactions between template (the oligo) and functional monomer.Initially, the imprinting of a 2'-deoxyadenosine dimer (1) was attempted. Due to the hydrophilicity of a DNA oligomer, it was difficult to find a suitable organic solvent that would solubilize the oligomers without disrupting the template's interaction with the polymer matrix [7]. To combat the solubility problems and to insure the homogeniety of the polymerization solution, we examined various polymer formulations with organic and/or aqueous-based solvents that would dissolve the template without disrupting these key interactions.
A Highly Sensitive and Selective Surface-Enhanced Nanobiosensor
Authors: Haes Amanda J. , Van Duyne Richard P. 
Published: April 2017

AbstractNanosphere lithography (NSL) derived triangular Ag nanoparticles were used to create an extremely sensitive and specific optical biological and chemical nanosensor. Using simple UV-vis spectroscopy, biotinylated surface-confined Ag nanoparticles were used to detect streptavidin down to one picomolar concentrations. The system was tested for nonspecific binding interactions with bovine serum albumin and was found to display virtually no adverse results. The extremely sensitive and selective response of the Ag nanoparticle sensor indicates an exciting use for biological and chemical sensing.
A Self-Locking Technique With Fast Response and High Sensitivity for Micro-Cantilever Based Sensing of Analytes
Authors: Mehta A. , Muralidharan G. , Passian A. , Cherian S. , Ferrell T.L. , Thundat T. 
Published: April 2017

AbstractMEMS based microcantilevers have been employed as sensors in both liquid and ambient conditions. One scheme for detection is based upon monitoring the change in microcantilever resonant frequency as a function of the adsorbed analyte concentration. However, the sensitivity is limited by the accuracy of the frequency measurements, which is a function of the Q-factor of the vibrating element and the measurement bandwidth. In this paper, we present a feedback scheme for self-locking amplification of the small-amplitude thermal oscillations of the microcantilever. Using this approach, we demonstrate an improvement in the Q-factor by two to three orders of magnitude as compared to that of the undriven microcantilever. Use of this technique eliminates the need for lock-in detection and results in improved response times for sensor applications. Experiments using the proposed feedback amplification technique show improved sensitivity for the detection of biological molecules in liquids, and for adsorbed vapors under ambient conditions.
Chemical Sensing With Resistive Microcantilevers
Authors: Muralidharan G. , Wig A. , Pinnaduwage L. A. , Hedden D. L. , Datskos P. G. , Thundat T. , Lareau R. T. 
Published: April 2017

AbstractMEMS-based microcantilevers have been proposed for a variety of biological and chemical sensing applications. Measuring the magnitude of microcantilever deflection due to adsorption-induced bending, and following the variation in the resonant frequency of the microcantilevers due to the adsorbed mass are two techniques commonly employed for sensing analytes. Apart from possessing a high level of sensitivity to small changes in mass, microcantilevers are also very sensitive to small changes in temperature and hence the flow of heat. One way of achieving high sensitivity in thermal measurements is by using a bimaterial microcantilever and measuring its deflection as a result of thermal fluctuations. Commercially available piezoresistive microcantilevers are an example of bimaterial cantilevers and in this study, we propose the use of such cantilevers for sensing explosives. We show that sensing can be accomplished by following the differences in the thermal response of the cantilevers introduced by the presence of explosives adsorbed from the vapor phase onto the surface of the cantilever. We discuss the issues involved in determining the sensitivity of detection and selectivity of detection.
Micromirror Arrays for High Temperature Operation
Authors: Almasri Mahmoud F. , Frazier Bruno A. 
Published: April 2017

AbstractThis paper describes the design, modeling, fabrication, and testing of electroplated metal electrostatic torsion micromirror arrays. The goal is to develop novel micromirror arrays optimized for high temperature operation for use in epitaxial growth systems such as MOCVD and MBE to define device structure and hence eliminate the need for etching and lithography. The metallic micromirror arrays were fabricated with a hexagonal shape and with diameters of 0.5 mm2 and 1mm2. The micromirror arrays were structurally composed of primarily electroplated nickel, a mechanically durable material with a high glass transition temperature and with controllable residual stress. The torsion beam was designed with a straight bar and serpentine shape in order to optimize the voltage necessary to tilt the micromirror by ± 10°. A finite element model built in Ansys has been employed to determine the micromirror geometries and performance. A voltage of 130 volts was required to rotate the mirror with a serpentine shape beams by 10°. In addition, the mirror was operated at a resonant frequency of 2.2 kHz.
Investigating Narrow Plasmons in Nanoparticle Arrays Fabricated Using Electron Beam Lithography.
Authors: Hicks Erin M. , Gunnarrsson Linda , Rindevicius Tomas , Zou Shengli , Kasemo Bengt , Käll Mikael , Schatz Goerge C. , Spears Kenneth G. , Duyne Richard P. Van 
Published: April 2017

AbstractThe improvement of nanofabrication is one of the driving forces behind advancements in the fields of electronics, photonics and sensors. Precise control over nanoscale architecture is an essential aspect in relating new size-dependent material properties. Direct writing methods such as Electron Beam Lithography (EBL), enable precise “user-defined” writing of nanostructures in a wide range of materials. Using electrodynamics calculations, Schatz and coworkers have discovered one dimensional array structures built from spherical silver nanoparticles that produce remarkably narrow plasmon resonance spectra upon irradiation with light that is polarized perpendicularly to the array axis. In order to investigate these interactions, precise control of nanoparticle orientation, size, shape and spacing is necessary. If the overall structures have excessive defects then the effect may not be seen. To have the best control over array fabrication and to look at these interactions experimentally, EBL was used to construct lines of circular cylinders of varying interparticle spacings. Dark field microscopy was used to look at overall sample homogeneity and collect the single particle plasmon resonance spectrum. Additionally, a UV-visible spectrometer with a variable angle stage was used to look at the bulk line properties. With experimental verification of the theory will lead to not only a more thorough understanding of the underlying principles of nanophotonics, but also application in biosensing, that potentially improve on current technologies.
Synthesis of Nanoscale Devices for Neural Electrophysiological Imaging
Authors: Dell'Acqua-Bellavitis Ludovico M. , Ballard Jake D. , Bizios Rena , Siegel Richard W. 
Published: April 2017

AbstractA device with nanometric resolution in space and millisecond resolution in time, intended for neural electrophysiological imaging applications, is being developed and fabricated for in vitro experimentation. The device consists of (i) an integrated circuit (IC) platform and (ii) a carbon nanotube/polymethylmethacrylate composite construct. Arrays of equi-spaced multiple gold electrodes were fabricated using combined e-beam and optical lithography to achieve three types of IC platforms with three different scales of resolution. Carbon nanotubes were synthesized on silicon dioxide substrates using a chemical vapor deposition method. Subsequently, the carbon nanotube arrays were infiltrated with in situ polymerized polymethylmethacrylate to achieve electrical insulation between adjacent nanotube bundles. The composite construct was fabricated and exhibited electrical conductivity and connectivity between two faces of the composite along the length of the nanotubes. The carbon nanotube arrays grown on silicon dioxide exhibited uniform length and a high level of alignment, which was preserved subsequent the in situ polymerization process. The devices can be deployed as an interface between ICs and mammalian cells.
Thermally Stimulated Electron Emission from Scratched Metal Surfaces
Authors: Nakayama Keiji , Matamura Hitoshi 
Published: April 2017

AbstractIn order to have a knowledge on electron emission from wearing metal surfaces under frictional heating, we investigated thermally stimulated electron emission (TSEE) phenomena together with thermoelectronic emission for 14 kinds of scratched metal surfaces, Al, Ti, V, Cr, Fe, Co, Ni, Cu, Mo, W, Pd, Pt, Ag and Au. The scratched metal surfaces in ambient air were thermally stimulated in a constant heating rate ranged from 1.3 to 4.4 °C/s from room temperature to 700 °C in a residual gas pressure of 10-4Pa in a vacuum chamber. During the stimulation, a channeling type secondary electron multiplier detected the electrons emitted from the scratched metal surfaces. The TSEE glow curves and the integrated electron emission intensities over tested temperature range for the metals are presented and the emission mechanisms are discussed.
Fabrication Methods for Improved Electromechanical Behavior in Piezoelectric Membranes
Authors: Robinson M.C. , Hayenga P.D. , Cho J.H. , Richards C.D. , Richards R.F. , Bahr D.F. 
Published: April 2017

AbstractPiezoelectric materials convert mechanical to electrical energy under stretching and bending conditions. Optimizing the coupling conversion is imperative to the electromechanical behavior of a micromachined membrane's performance. This paper discusses analytical calculations that were devised to determine the microscale structure that minimizes residual stress and outlines the implementation of fabrication technique variations including three different electrode configurations, trenching around the membrane, and reducing the total composite residual stress of the support structure using compressive silicon oxide. Lead zirconacte titanate (PZT) films between 1 and 3 μm thick with a ratio of Zr to Ti of 40:60 were deposited onto 3 mm square silicon membranes. The total tensile stress in the composite structure reaches 100 MPa during standard fabrication processing. Utilizing analytical calculations, a structure was determined that lowered the residual stress of the composite to 11 MPa and increased the electromechanical coupling 35 times. Changing the geometry of the electrode coverage decreased the residual stress of the composite by 40%. Trenching around the membrane provided a membrane with boundary conditions that approached simply supported and decreased the composite residual stress by another 16%. A comparison of the electromechanical behavior for these structures will be discussed, showing a route towards increasing electromechanical coupling in PZT MEMS.
Space Charge Limited Current in Porous Silicon with traces of Nitrogen Dioxide
Authors: Borini Stefano , Rossi Andrea M. , Boarino Luca , Amato Giampiero 
Published: April 2017

AbstractThe discovery of the steep increase of electrical conductivity in Porous Silicon (PS) samples in contact with Nitrogen Dioxide, NO2, opens the possibility to study the electrical conduction processes in nanostructured systems from a completely new point of view. The system undergoes a change of conductivity of 5 orders of magnitude when exposed to few ppm of NO2, whereas the free charge concentration increases by only one order of magnitude in the same pressure range. Upon NO2 exposure the system transition from an “insulator-like” to a “semiconductor-like” behaviour can be studied by means of several techniques. In this paper, the results from a Space Charge Limited Current (SCLC) study unambiguously demonstrate the change of the charging status of defects upon NO2exposure, and explain some “exotic” effects recently reported.
In-Situ Pretreatment Approach for Surface Deterioration Alleviation Amidst Thermal Desorption of Si(100)
Authors: Pun A.F. , Wang X. , Meeks J.B. , Durbin S.M , Zheng J.P. 
Published: April 2017

AbstractWithin this article, a novel in-situ method is proposed as a modification of thermal desorption utilizing pretreatment which can be applied to systems subject to material deposition, substrate heating, and creation of non-oxidizing environments (vacuum or inert atmosphere). Following the theoretical development of this proposed method, involving the fue ling of the oxide-reduction reaction with segregated sacrificial material, the method is demonstrated experimentally on Si (100) wafers utilizing ex-situ atomic force microscopy for resulting surface topography analysis and in-situreflective high-energy electron diffraction for crystalline information during the modified thermal desorption progression.
Surface Electronic States and Electrostatic Attractive Forces between Metals or Semiconductor and Tribocharged Polymers
Authors: Momose Yoshihiro , Umeki Masahiro , Suzuki Daisuke , Nakayama Keiji 
Published: April 2017

AbstractA new simple method for measuring a long-range electrostatic attractive force between metal and semiconductor substrate and charged polymer surfaces has been developed to make clear the effect of the electronic nature of substrate surfaces. Nickel, titanium, and silicon wafer substrates were subjected to various surface pretreatments. The surfaces of polystyrene and polytetrafluoroethylene sheets were positively and negatively charged by triboelectrification, respectively. A progressive increase in the attractive force was observed with a decrease in the distance between the substrate and polymer surfaces. The magnitude of the attractive force was greatly influenced by the substrate pretreatments and the polymers with the oppositely charged surface. The electronic nature of the substrate surfaces evaluated by temperature programmed photoelectron emission method was well correlated with the attractive force. The electrostatic induction generated at the substrate surface is considered to govern the attractive force.
Strain Transduction in Conductor-Modified Polymers
Authors: Hantsoo Eerik T. , Chial Vanessa B. , Zhao Yanan , Chan Kevin C. , Rose Klint A. , Wu Kenneth S. , Pruitt Beth L. 
Published: April 2017

AbstractWe present the fabrication and electromechanical characterization of a class of polymeric high-elongation strain sensors. Samples of polydimethylsiloxane were coated with Creative Materials, Inc.'s 123-27 Electrically Conductive Silicone Ink and the resistance behavior was evaluated in uniaxial tensile tests. Large strains (up to 100%) were observed with monotonically increasing resistance changes. A clear, linear trend up to 65% strain dominated the resistance vs. strain behavior then resistance increased non-linearly. Image processing of the film coupled with a finite element conduction simulation indicate the change in resistance is primarily a geometric effect. Both the conduction path and the polydimethylsiloxane substrate break completely around 100% strain. The samples exhibit a gauge factor of approximately 10.
Characterization of Ti/TiN and TiN Conductive Layer for High Temperature MEMS Devices
Authors: Lange Peter , Ohlsen Birger , Puls Sebastian , Syre Joerg 
Published: April 2017

AbstractThe effects of temperature on micro heaters made of Ti/TiN stacks and pure TiN layers on bulk micromachined membranes have been studied. Ti/TiN stacks show a thermal stability up to 380°C, beyond that temperature an enhanced interaction within the stack and/or with adjacend layers leads to a degradation of the resistance. The pure TiN layers withstand temperatures up to 600 °C, this limitation is only given by the mechanical stability of the membran stack, which is destroyed beyond this temperature. These layers are suitable for sensors in which an elevated temperature provided by heating lines on a membran for thermal isolation and fast response is necessary for functionality.
Exchange Spring Type Magnet Realized in FePt/Fe Multilayers Deposited by Magnetron Sputtering
Authors: Gu Yousong , Zhang Dayong , Zhan Xiaoyuan , Ji Zhen , Zhen Xiaolan , Zhang Yue 
Published: April 2017

AbstractSeries of FePt/Fe multilayers with different layer thicknesses have been deposited on Si substrates by magnetron sputtering and post annealing at different temperatures and durations. The structure, surface morphology, composition, and magnetic properties of the deposited films have been characterized by XRD, SEM, EDX and VSM. It is found that after annealing at temperatures above 500°C, FePt phase undergoes a phase transition from disorder fcc into ordered fct structure, and become a hard magnetic phase. For [FePt/Fe]n multilayer with varying Fe layer thickness, lattice constants and grain sizes change with Fe layer thickness and annealing temperature. The coercivities of [FePt/Fe]n multilayers decrease with Fe layer deposition time, and the energy product (BH)max shows a maximum with Fe layer thickness. Optimization on layer thickness leads a high (BxH)max value of 15.2MGOe for [FePt(8min)/Fe(4min)]8. The effects of quick annealing and Ag underlayer on the structure and magnetic properties were also studied.
Association of serum vitamin D levels and transient tachypnea of newborn: a case control study
Authors: Singh Gurmeet , Sood Reena , Narang Gursharan Singh , Brar Harnoorjit Kaur , Bagga Amanjeet Kaur 
Published: April 2017

Background: Transient tachypnea of newborn (TTN) is a common cause of respiratory distress in newborns with estimated incidence of 1-2% of all newborns. Although a self-limiting transient condition but it may cause severe morbidities. This study was conducted to find association of serum vitamin D levels in neonates who develop TTN as compared to normal healthy neonates.Methods: With thorough history with structured questionnaire and lab tests, serum vitamin D levels of 45 neonates who develop TTN were compared with 56 healthy neonates in control group.Results: Out of 45 neonates who develop TTN 39(86.7%) were deficient in vitamin D as compared to control group where 33(58.9%) out of 56 healthy neonates were deficient in vitamin D.Conclusions: Lower vitamin D levels at birth in term neonates is associated with increased risk of developing TTN and vitamin D may have a role in its pathogenesis.