Rearrangement collisions between gold clusters

Collision processes between two gold clusters are investigated using classical molecular dynamics in combination with embedded atom (EA) potentials, after checking the reliability of EA results by contrasting them with first principles calculations. The Au projectiles considered are both single atoms (N=1) and clusters of N=2, 12, 13 and 14 atoms. The targets contain N= 12, 13 and 14 gold atoms. The initial projectile energy E is in the range 0 < E < 1.5 eV/atom. The results of the collision processes are described and analyzed in detail.Comment: LATeX file, 8 figures, uses svjour.cl

Mast cell quantification and substance P immunoreactivity during the acute and chronic stages of pneumonic pasteurellosis in ruminants

The objective of this work was to determine the numbers of stained mast cells (MCs) and substance P (SP) immunoreactivity during the initiation and progression of pulmonary lesions in a model of pneumonic pasteurellosis (PP) in ruminants. The first experiment demonstrated that, at 6 h after intrabronchial deposition of Mannheimia (Pasteurella) haemolytica in neonatal calves, MC numbers decreased in sites of severe lung damage. Prior administration of a sialyl Lewis mimetic (TBC1269) intended to prevent neutrophil infiltration had no effect on MC numbers, suggesting that MC degranulation is unaffected by selectin inhibition. In the second study, a single high dose of dihydrocapsaicin (DHC) administered to neonatal lambs depleted peptidergic nerves of SP. Depletion was measured in nasal septum, the site richest in SP fibers, and was estimated to be 85% of controls. In the upper and lower respiratory tract MCs density increased progressively with age, from 3 to 21 days, but DHC-treated animals had significantly higher numbers of MCs; this suggests a functional association between MCs and SP fibers. Histamine content in the lung was similar to controls. The model is suitable for studies of the inflammatory response in the respiratory tract when the neurogenic contribution is reduced. In the third experiment, diminished numbers of MCs and histamine during the acute phase (1 day) of PP in sheep were associated with SP immunoreactivity in macrophages infiltrating the areas of severe damage, suggesting an extraneural source of SP. At 15 days, MCs were scarce at sites with pyogranulomatous foci, but increased in areas with interstitial pneumonia. Substance P immunoreactivity demonstrated that not only an extrinsic sensory innervation, but also an intrinsic contribution of pulmonary ganglion neurons, sustain the inflammatory response. At 45 days the fibroplastic changes in pleura, interlobular spaces, and interstitium were marked, as was the presence of bronchiolitis obliterans. These changes were associated with an increased number of MCs; however, the elevation in histamine did not correspond with the MCs increment. In areas of severe fibrosis SP immunoreactivity in nerve fibers was mild suggesting that the absence of SP during chronic PP hinders tissue repair

Energy harvesting from body motion using rotational micro-generation

Autonomous system applications are typically limited by the power supply operational lifetime when battery replacement is difficult or costly. A trade-off between battery size and battery life is usually calculated to determine the device capability and lifespan. As a result, energy harvesting research has gained importance as society searches for alternative energy sources for power generation. For instance, energy harvesting has been a proven alternative for powering solar-based calculators and self-winding wristwatches. Thus, the use of energy harvesting technology can make it possible to assist or replace batteries for portable, wearable, or surgically-implantable autonomous systems. Applications such as cardiac pacemakers or electrical stimulation applications can benefit from this approach since the number of surgeries for battery replacement can be reduced or eliminated. Research on energy scavenging from body motion has been investigated to evaluate the feasibility of powering wearable or implantable systems. Energy from walking has been previously extracted using generators placed on shoes, backpacks, and knee braces while producing power levels ranging from milliwatts to watts. The research presented in this paper examines the available power from walking and running at several body locations. The ankle, knee, hip, chest, wrist, elbow, upper arm, side of the head, and back of the head were the chosen target localizations. Joints were preferred since they experience the most drastic acceleration changes. For this, a motor-driven treadmill test was performed on 11 healthy individuals at several walking (1-4 mph) and running (2-5 mph) speeds. The treadmill test provided the acceleration magnitudes from the listed body locations. Power can be estimated from the treadmill evaluation since it is proportional to the acceleration and frequency of occurrence. Available power output from walking was determined to be greater than 1mW/cm³ for most body locations while being over 10mW/cm³ at the foot and ankle locations. Available power from running was found to be almost 10 times higher than that from walking. Most energy harvester topologies use linear generator approaches that are well suited to fixed-frequency vibrations with sub-millimeter amplitude oscillations. In contrast, body motion is characterized with a wide frequency spectrum and larger amplitudes. A generator prototype based on self-winding wristwatches is deemed to be appropriate for harvesting body motion since it is not limited to operate at fixed-frequencies or restricted displacements. Electromagnetic generation is typically favored because of its slightly higher power output per unit volume. Then, a nonharmonic oscillating rotational energy scavenger prototype is proposed to harness body motion. The electromagnetic generator follows the approach from small wind turbine designs that overcome the lack of a gearbox by using a larger number of coil and magnets arrangements. The device presented here is composed of a rotor with multiple-pole permanent magnets having an eccentric weight and a stator composed of stacked planar coils. The rotor oscillations induce a voltage on the planar coil due to the eccentric mass unbalance produced by body motion. A meso-scale prototype device was then built and evaluated for energy generation. The meso-scale casing and rotor were constructed on PMMA with the help of a CNC mill machine. Commercially available discrete magnets were encased in a 25mm rotor. Commercial copper-coated polyimide film was employed to manufacture the planar coils using MEMS fabrication processes. Jewel bearings were used to finalize the arrangement. The prototypes were also tested at the listed body locations. A meso-scale generator with a 2-layer coil was capable to extract up to 234 µW of power at the ankle while walking at 3mph with a 2cm³ prototype for a power density of 117 µW/cm³. This dissertation presents the analysis of available power from walking and running at different speeds and the development of an unobtrusive miniature energy harvesting generator for body motion. Power generation indicates the possibility of powering devices by extracting energy from body motion

Análisis de los patrones de distribución de plancton en el Estrecho de Gibraltar asociados al forzamiento mareal y meteorológico

El Estrecho de Gibraltar es la única conexión entre la circulación global y el Mar Mediterráneo, el mayor cuerpo de agua semicerrado del planeta. Por lo tanto los procesos que aquí ocurren son claves para describir los flujos biogeoquímicos en la cuenca mediterránea y fundamentales para la circulación termohalina global. En el Estrecho se ha descrito una circulación “estuarina-inversa” con aguas atlánticas entrando en superficie y aguas mediterráneas más densas en profundidad. Sobre este patrón general existen alteraciones debidas al forzamiento mareal y el atmosférico o subinercial. La gran cantidad de procesos físicos y en varias escalas que ocurren en el Estrecho lo hacen muy atractivo desde el punto de vista del acoplamiento físicabiología en el ecosistema pelágico. El propósito de esta Tesis es la descripción de los patrones biogeoquímicos en el área de influencia del Estrecho, intentando cubrir un rango amplio de fenómenos con diferentes escalas espacio-temporales. Las zonas de plataforma a ambos márgenes del canal principal del Estrecho (especialmente la noroccidental) presentan una alta actividad del fitoplancton con células grandes y activas. En contraposición, la zona del canal originalmente presenta aguas oligotróficas provenientes del Golfo de Cádiz. Estas aguas oligotróficas (a través del NACW) aportan el 70% del nitrato transportado anualmente a las cuencas mediterráneas y el 55% de la biomasa fitoplanctonica. Sin embargo, existen intrusiones de aguas costeras hacia el canal relacionados con la generación de ondas internas y divergencias superficiales que éstas crean. Estos procesos se dan tanto en mareas vivas como en muertas, estando durante las vivas acompañados de alta mezcla interfacial. Los procesos derivados de las ondas internas (Tipo I) pueden significar un 30% del nitrato transportado hacia las cuencas mediterráneas, acompañadas de células activas y grandes. Este aporte también supone el 30% de la biomasa total del fitoplancton transportada. A su vez, la mezcla interfacial y adelgazamiento de la capa atlántica pueden alterar el ciclo estacional del fitoplancton de las aguas atlánticas entrantes. Estos procesos pueden aumentar la producción primaria y la biomasa, especialmente durante primavera y otoño. Estos procesos también favorecen la dominancia de nanoflagelados (primavera y otoño) y picofitoplancton (verano). Por otro lado, la turbulencia es capaz de redistribuir la biomasa del fitoplancton en vertical, siempre que existan las condiciones físico-biológicas para que se genere un máximo profundo. La relación entre turbulencia y velocidad de sedimentación del fitoplancton hace que estos máximos se sitúen bajo zonas de mayores niveles de turbulencia (mayores velocidades de sedimentación). En el futuro con mayor estratificación y mayor entrada superficial de turbulencia, la biomasa integrada de fitoplancton será menor en la capa de mezcla pero la exportación vertical de materia al océano profundo será mayor. Finalmente, los procesos ocurrentes en el Estrecho permiten que el Mar de Alborán reciba una aportación cuasi-constante de biomasa de fitoplancton y nutrientes, este último en un orden de magnitud mayor a la aportación de los afloramientos costeros descritos en esta cuenca. Estos fenómenos podrían fertilizar y mantener alta la producción primaria en esta área descrita como más productiva del Mediterráneo

Increase of the Energy Necessary to Probe Ultraviolet Theories Due to the Presence of a Strong Magnetic Field

We use the gauge gravity correspondence to study the renormalization group flow of a double trace fermionic operator in a quark-gluon plasma subject to the influence of a strong magnetic field and compare it with the results for the case at zero temperature and no magnetic field, where the flow between two fixed points is observed. Our results show that the energy necessary to access the physics of the ultraviolet theory increases with the intensity of the magnetic field under which the processes happen. We provide arguments to support that this increase is scheme independent, and to exhibit further evidence we do a very simple calculation showing that the dimensional reduction expected in the gauge theory in this scenario is effective up to an energy scale that grows with the strength of such a background field. We also show that independently of the renormalization scheme, the coupling of the double trace operators in the ultraviolet fixed point increases with the intensity of the background field. These effects combined can change both, the processes that are expected to be involved in a collision experiment at a given energy and the azimuthal anisotropy of the measurements resulting of them.Comment: 23 pages, 10 figures. Added section about renormalization scheme independenc

MASTER OF SOCIAL WORK STUDENTS\u27 PERCEIVED PREPAREDNESS TO ADDRESS MENTAL HEALTH NEEDS OF CAREGIVERS WORKING TOWARD REUNIFICATION

The purpose of this study is to assess Master of Social Work (MSW) students’ perspectives on their preparedness to identify mental health needs of caregivers that are working toward reunification. Research has established that caregivers with mental illness have children removed by the child welfare system at higher rates. In order to reunify successfully, it is critical that any mental health needs are identified to provide appropriate linkage to services. This quantitative study used a self-administered survey questionnaire with a case study vignette. MSW students have some exposure to diagnosing during their MSW program, however, the findings suggest that key factors such as area of specialization, length of experience in a mental health setting, and mental health diagnosing experience, impact how comfortable they are with diagnosing and recognizing the severity of mental health symptoms

Development of LiDAR assisted terrestrial radar interferometry for rock deformation monitoring

Rock and soil slope movements cost millions of dollars annually. During the past few decades, engineers have relied on traditional methods to detect slope movements. These tools are valuable for small spatial areas but, may not be adequate or cost effective for large spatial areas. Remote sensing methods such as terrestrial laser scanning (TLS) and terrestrial radar interferometry (TRI) provide excellent spatial coverage, and with adequate post-data-processing software, sub-millimetric scale deformation sensitivity can be achieved. This work will present a comparative experimental study between TLS and TRI. The comparative experimental study will allow us to achieve the two main objectives of this research: 1. The development of a methodology to correct repositioning errors of the TRI during discontinuous measurement campaigns. 2. The development of a methodology to use TLS as an independent measurement device to constrain the results of the TRI when rock displacements exceed multiple wavelengths of the instrument or displacements exceed one quarter of the wavelength of the instrument. Results from the measurement campaigns show that sub-millimetric displacements can be detected with both TLS and TRI systems. Furthermore, TLS systems are widely available, cheaper, lighter, and easier to operate than TRI systems. Data can also be reduced faster, and the results more easily interpreted than with TRI systems. These advantages make TLS systems ideal for rock slope evaluation for highway projects, especially when time, cost, and public opinion are major concerns for the state\u27s Department of Transportation --Abstract, page iv

Damages caused by cotton rat, Sigmodon hispidus zanjonensis, on sugar cane in San Pedrosula, Honduras

Technical assistance was given to Compañía Azucarera Hondureña, S.A. (Agro-Industrial Co.), Honduras, Central America, to determine if a campaign against noxious rodents to agriculture crops was needed. Several trappings were carried out at different places using snap traps to determine the population structure of rodents associated with the crop, and live traps to determine the index or density of the Sigmodon hispidus rat population, which was identified as being responsible for the damage to sugarcane. Results were 43.24% adult males, 14.86% young males, 31.41% adult females, and 10.47% young females. Of the adult females captured, 54.83% were pregnant with an average of 3 to 4 embryos per rat. A control demonstration combat was carried out at one of the experimental stations with a bait prepared with 2% zinc phosphide in a place where it had been previously determined there was a population of 39 rats per hectare. After such control, the population was reduced to 18 rats per hectare, which represents an efficiency of 53.85%. An evaluation of damages was also measured at different places to determine the degree of loss caused by the rats, which proved to be 22.79% damage. The size of the sample was estimated in 3 samples per hectare, with a level of confidence of 95%

3D human pose estimation from depth maps using a deep combination of poses

Many real-world applications require the estimation of human body joints for higher-level tasks as, for example, human behaviour understanding. In recent years, depth sensors have become a popular approach to obtain three-dimensional information. The depth maps generated by these sensors provide information that can be employed to disambiguate the poses observed in two-dimensional images. This work addresses the problem of 3D human pose estimation from depth maps employing a Deep Learning approach. We propose a model, named Deep Depth Pose (DDP), which receives a depth map containing a person and a set of predefined 3D prototype poses and returns the 3D position of the body joints of the person. In particular, DDP is defined as a ConvNet that computes the specific weights needed to linearly combine the prototypes for the given input. We have thoroughly evaluated DDP on the challenging 'ITOP' and 'UBC3V' datasets, which respectively depict realistic and synthetic samples, defining a new state-of-the-art on them.Comment: Accepted for publication at "Journal of Visual Communication and Image Representation

Information and Communication Technologies (ICTS) as a Tool for Intercultural Education. A collaborative experience in secondary education in Tlapa de Comonfort, Guerrero, Mexico

This paper discusses the collaborative experience of creating educational materials for a secondary school in Tlapa de Comonfort, Guerrero, México. In this school, students from Nahuatl, Tun savi, Me'phaa and Spanish speaking communities live and learn together. The intercultural context provides challenges for science education that we sought to address. The use of collaborative technologies in science classes has made visible the cultural diversity in the classroom, helping students and teachers recognize themselves as active agents in the construction of common knowledge and in sharing their\ud knowledge. This experience also shows the importance of ICTs as technologies of expression that reinforce individual and collective identity in intercultural contexts