COLD SPRAY SURFACE PATTERNING OF ALUMINUM ON ALUMINUM, SILICON, GLASS, AND PRINTED CIRCUIT BOARD SUBSTRATES

The aim of the present study is to investigate the feasibility of and the criteria for using the cold spray technique for surface patterning to create two-dimensional surface features on various substrates. Metal meshes were used as screens for surface patterning in this investigation; fabricated features were characterized with optical microscope, scanning electron microscope, and optical profilometer. Processing parameters like mesh size, standoff distance, gun traverse speed, and number of spray passes were examined to study their influence on the morphology of the fabricated features. Two-dimensional aluminum features were successfully fabricated on aluminum, soda-lime glass, silicon wafer, and the copper foil-layer of printed circuit board. The smallest feature, created with -45 to +5 µm aluminum feedstock powders, has an average size of 67.4 µm. It was determined that the pore size of a mesh needs to be at least 3.3 times bigger than the average size of feedstock powders in order to create features successfully. To estimate the probability of feedstock powders passing through a mesh and simulate the topography of the fabricated features, a Monte Carlo simulation incorporating the particles’ size distribution and the geometry meshes was developed. With the capability of creating features on diverse substrates, the cold spray surface patterning technique shows promising potential to create heterogeneous two-dimensional functional features or devices at micron size with high efficiency.Lieutenant Commander, Peruvian NavyApproved for public release. Distribution is unlimited

Cold spray surface patterning of aluminum on aluminum, silicon, glass, and printed circuit board substrates

17 USC 105 interim-entered record; under review.The aim of the present study is to investigate the feasibility and the criteria of using the cold spray technique for surface patterning to create two-dimensional surface features on various substrates. Metal meshes (16, 45, 170, 200, 400, and 5/16″) were used as screens for surface patterning in this investigation; fabricated features were characterized with optical microscope, scanning electron microscope, and optical profilometer. Processing parameters like mesh size, standoff distance, gun traverse speed, and number of spray passes were examined to study their influence to the morphology of the fabricated features. Two-dimensional aluminum features were successfully fabricated on aluminum, soda-lime glass, silicon wafer, and the copper foil-layer of printed circuit board. The smallest feature created with −45 to +5 μm aluminum feedstock powders, has an average size of 67.4 μm. It was determined that the pore size of a mesh needs to be at least 3.3 times bigger than the average size of feedstock powders in order to create features successfully. To estimate the probability of feedstock powders passing through a mesh and simulate the topography of the fabricated features, a Monte Carlo simulation incorporating the particle size distribution and the geometries of meshes was developed. With the capability of creating features on diverse substrates, the cold spray surface patterning technique shows promising potential to create heterogeneous two-dimensional functional features or devices at micron-sized with high efficiency.This work was funded by the Department of Mechanical and Aerospace Engineering of the Naval Postgraduate School

PERFORMANCE ADAPTATIONS TO SHORT-TERM SLED TOWING AND SPRINT TRAINING

The use of resisted sprinting techniques is common both in athletics and in a variety of sports (Cronin and Hansen, 2006). However, previous research has focused in studying the performance when applying these methods on untrained subjects (Zafeiridis et al., 2005; Kristensen et al., 2006). Considering that the magnitudes and time courses of the neural adaptations in the neuromuscular system in elite athletes may differ from those adaptations reported for untrained athletes (Hakkinen et al., 1987), the results from those papers may not be representative of the experienced subjects. Therefore, the aim of the study was to examine the effects of resisted and unloaded sprint training programs on acceleration, transition and maximum speed performance on experienced athletes

Frecuencia cardiaca, formas de organización y situaciones de juego en baloncesto

Introduction: The purpose of this study was to find out the effect of task organization and different game situations on intensity and of repetitions in basketball. Method: A quasi-experimental design with twelve players group of 12, 4 ± 0, 7 years-old average was done. Three training sessions about lay-up was realized. The independent variables were task organization and different game situations. The dependent variables were heart rate and number of repetitions, and player´s perception about intensity and work. Results: a) statistically significant differences in heart rate between the status of 1x0 and 2x2 (p =. 014), and trends towards significance between the situation of game 1x0 and 3x3 (p =. 065), b) were statistically significant differences in heart rate between the situation frequents gaming 1x0 circuit on the rows (p =. 027) and forms involving simultaneous moves (p =. 000), and the game situation 1x1 between rows with respect to the ways games with simultaneous participation (p =. 014); c) The effect of the interaction between the game situation factor and type of organization was statistically significant (F6, 42 = 9,256, p =. 000 ). Are statistically significant differences in the number of operations performed by the players on the combination of the four game situations and the three types of organization. Conclusions: a) The groups in circuits had a greater number of repetitions and intensity perceived, b) the groups in games through forms showed greater heart rate and more repetitions, and c) the group in rows presented no value to excel regard to the task structure. From the collected data, it is deduced that depending on which are the objectives of the sports abilities, will be more useful adapted to use a type of organization or another one.Introducción: El presente trabajo analiza la influencia de diferentes formas de organización y situaciones de juego sobre la intensidad y el número de intervenciones en baloncesto. Método: Se realizó un diseño cuasi-experimental, con 12 jugadores de edad 12,4 ± 0,7, años. Se realizaron tres sesiones de intervención sobre el lanzamiento a canasta en carrera (entrada a canasta). Las variables independientes fueron la forma de organización y las diferentes situaciones de juego. Las variables dependientes fueron la frecuencia cardiaca media, el número de intervenciones de lanzamientos, y la percepción de la intensidad de trabajo de los jugadores. Resultados: a) se observan diferencias estadísticamente significativas en frecuencia cardiaca entre la situación de 1x0 y la de 2x2 (p=.014), y tendencias a la significación entre la situación de juego de 1x0 y la de 3x3 (p=.065), b) Se aprecian diferencias estadísticamente significativas en frecuenta cardiaca entre la situación de juego de 1x0 en circuito con respecto a las filas (p=.027) y las formas jugadas con participación simultanea (p=.000), y en la situación de juego de 1x1 entre filas con respecto a las formas jugadas con participación simultanea (p=.014); c) El efecto de la interacción entre el factor situación de juego y tipo de organización fue estadísticamente significativo (F6,42 = 9.256, p=.000). Se aprecian diferencias estadísticamente significativas en el número de intervenciones realizadas por los jugadores en la combinación de las cuatro situaciones de juego y los tres tipos de organización. Conclusiones: a) La organización grupal con participación simultánea mediante circuitos presentó mayor número de intervenciones e intensidad percibida; b) la organización grupal con participación simultánea mediante formas jugadas con participación simultanea mostró mayor frecuencia cardiaca y más intervenciones; y c) la organización grupal con participación alternativa mediante filas no presentó ningún valor que sobresalga respecto a las formas de organización. A partir de los datos obtenidos, se deduce que dependiendo de cuáles sean los objetivos de la habilidad deportiva, será más adecuado utilizar un tipo de organización u otro

DETERMINING THE OPTIMAL LOAD FOR RESISTED SPRINT TRAINING WITH SLED TOWING. A PILOT STUDY.

An excessive load in resisted sprint training can produce changes in running patterns. Load control is essential to ensure specificity of these training methods. The most common way to control is the percentage of speed lost in relation to maximum speed. The aim of the study was establishing the load for sprint training with sled towing in the maximum velocity phase. 12 athletes, Spanish national level, participated in the study. They run 30 m flying sprints, an unloaded sprint and sprints pulling loads of 6%, 10%, and 15% of their body mass, on a synthetic track surface wearing spikes. The regression equation obtained was: % Body mass = (-0.8325 · % velocity) + 84.08. This equation is specific for the type of surface used and the sled towing characteristics. Therefore, when using different surfaces and sled towings, specific equations should be calculated

A Discrete Four Stroke Quantum Heat Engine Exploring the Origin of Friction

The optimal power performance of a first principle quantum heat engine model shows friction-like phenomena when the internal fluid Hamiltonian does not commute with the external control field. The model is based on interacting two-level-systems where the external magnetic field serves as a control variable.Comment: 4 pages 3 figure

EFFECTS OF DIFFERENT RESISTED SPRINT RUNNING METHODS ON STRIDE LENGTH, STRIDE FREQUENCY, AND CG VERTICAL OSCILLATION

Sprint velocity can be increased thanks to specific strength improvements (Korchemny, 1985). The training principle of specificity states that for a training session to be effective, it must maintain similar characteristics to the sport requirements (Sale, 2003). With the use of resisted sprint running methods, possible benefits are specific strength improvements and an increase in stride length (Faccioni, 1994). However, these methods have not been scientifically proven yet (Sheppard, 2004)

A determination of the average up-down, strange and charm quark masses from Nf=2+1+1N_f=2+1+1

We present a lattice QCD determination of the average up-down, strange and charm quark masses based on simulations performed by the European Twisted Mass Collaboration with $N_f = 2 + 1 + 1$ dynamical fermions. We simulated at three different values of the lattice spacing, the smallest being approximately $0.06fm$, and with pion masses as small as $210 \text{MeV}$. Our results are: $m_{ud}(2\text{GeV})=3.70(17)\text{MeV}$, $m_s(2\text{GeV})=99.2(3.9)\text{MeV}$, $m_c(m_c)=1.350(49)\text{GeV}$, $m_s/m_{ud}=26.64(30)$ and $m_c/m_s=11.65(12)$

Changing the paradigm in postherpetic neuralgia treatment: lidocaine 700 mg medicated plaster

OBJECTIVE: Chronic pain is currently considered a disease state with biopsychosocial consequences and a negative impact on patients' quality of life (QoL). Pain from postherpetic neuralgia (PHN) can persist for months or years and is a prototypical example of chronic pain. We analyzed PHN as a model of chronic pain. including its effects on QoL and clinical aspects. We explored treatment options, focusing on the topical treatment with lidocaine 700 mg medicated plaster (LMP) and how this impacts PHN management.MATERIALS AND METHODS: This article is a narrative review of published studies. Preclinical and clinical studies were retrieved from literature through a search performed in PubMed/MEDLINE.RESULTS: To choose the appropriate treatment for chronic pains, such as PHN, not only efficacy but also tolerability, manageability, practicality, and compliance are important factors. especially in the long term. It is also important to set treatment expectations with the patients as total suppression of pain may be unrealistic. and a balance needs to be found between pain control and the minimization of adverse events. In this respect, LMP may be the best currently available treatment: it is easy to use, has low systemic absorption and thus a low risk for pharmacological interactions. Therefore, treatments can be personalized, and concomitant medications can be added, if needed. Recent data from a real-world study support this view by showing that LMP has superior effectiveness in reducing pain and improving the QoL compared to other commonly used systemic treatments and confirming its good tolerability profile that is mainly characterized by localized skin reactions.CONCLUSIONS: LMP is one of the best currently available treatment options for PHN patients balancing good efficacy with an excellent tolerability profile and can therefore be considered for use as a first-line treatment for PHN

Diferencias en los indicadores de rendimiento técnico-tácticos entre ganadores y perdedores en la Women Rugby World Cup 2010

El objetivo del presente estudio fue conocer las diferencias en acciones técnico - tácticas entre equipos ganadores y perdedores en equipos de rugby femenino de alto rendimiento. Se analizaron 30 partidos disputados entre 12 equipos nacionales de la Women Rugby World Cup 2010. Las variablesde estudio fueron las conductas relativas a la obtención del balón, el desarrollo del juego, a los reagrupa mientos, los puntos marcados, y las faltas reglamentarias. Se realizó un análisis descriptivo e inferencial de los datos (prueba T de Student y análisis discriminate). Los equipos ganadores realizan más ensayos, transformaciones de ensayos, y pierden menos rucks y touches que los perdedores. Estos resultados pueden usarse como valores de referencia para el entrenamiento y el análisis del rendimiento en competición