bluuebunny/crossref_metadata_2025_split huggingface dataset:
Micro-Computed Tomography to Finite Element Analysis of In Vivo Biodegradable Magnesium-Alloy Screw and Surrounding Bone in Rabbit Femurs
Authors: Williams Adrienne F. O. , McCullough Matthew B. A. 
Published: March 2016

Magnesium (Mg) and its alloys are attractive orthopedic biomaterials because of their degradability and mechanical properties, which are similar to bone’s. Characterizing the mechanical changes and interactions of these promising degradable biomaterials and the host environment (bone) is essential to their success in orthopedic devices.
The objective of this study was to develop a protocol to evaluate in vivo biodegradable Mg-alloy screws and surrounding new and cancellous bone in rabbit femurs over time, using high resolution micro-computed tomography (micro-CT) images and the finite element method.
Micro-CT was used to visually evaluate bone remodeling and degradation of Mg-alloy screws that were implanted in rabbit femoral condyles for 2, 4, 12, 24, 36 and 52 weeks. Over time, the degradation product around the device and the remainder of the intact core was observed. Scans were segmented into bone, degradation/corrosion products and non-degraded device, then reconstructed into 3D volumes. These volumes were meshed and assigned material properties based on CT data. The meshed volumes were exported to finite element software and analyzed in a virtual environment.
Several foundational observations were made about animal modeling of in vivo degrading magnesium devices with a micro-CT to FEA protocol.
Load Distribution in Barefoot Running Shoes
Authors: Gnagne Raoul , Barez Fred , Kao James , El-Hage Amer 
Published: March 2016

Running is one of the most practiced sports around the world and it dates back to Ancient Greece. Running became an Olympic sport in 1896 and today is mostly performed for fun and to stay in shape. Nowadays, athletic shoe companies make claims on the performance of the type of shoes they manufacture. Some of their claims include shoes that allow free movements, fit like a glove, and are in complete harmony with human mechanics. The preceding characteristics are those of so-called barefoot running shoes. Robillard [1] explains that minimalist running shoes could be defined as those that provide limited or no support and only minimal protection, with the heel at the same level as the forefoot. Even though running may have been investigated, however, there is not enough analyses on barefoot running shoes. The objective of this study was to investigate the load distribution on the feet of a healthy running adult wearing barefoot shoes through experimental work and finite element analysis (FEA).
The methodology used in this study included experimental as well FEA. Tests were conducted with a 175-lb adult subject wearing a pair of minimalist shoes. Experimental data were collected and used to perform Finite Element Analysis. The barefoot shoes were modeled with an equivalent thickness of 0.453 inch, and the following parameters were experimentally determined such as the Young’s modulus of 467 psi, a density of 0.0025 lb/in3, and a Poisson’s ratio of 0.08.
The simulation results yielded a maximum compressive stress of 38.71 psi in the toe region. This stress level was approximately one-half of the stresses generated in the heel region of conventional sport shoes. This study, further, revealed the reduction of stresses at the heel region with barefoot shoes resulting in lower risk of pain and injury to the foot in the absence of impact transients ordinarily experienced with conventional shoes.
Pulsatile Primary Slurry Atomization: Effects of Viscosity, Circumferential Domain, and Annular Slurry Thickness
Authors: Strasser Wayne , Battaglia Francine 
Published: March 2016

A central theme of our prior experimental and computational work on a transonic self-sustaining pulsatile three-stream coaxial airblast injector involved obtaining spectral content from compressible 2-D models and preliminary droplet size distributions from incompressible 3-D models. The three streams entail an inner low-speed gas, and outer high-speed gas, and an annular liquid sheet. Local Mach numbers in the pre-filming region exceed unity due to gas flow blockage by the liquid. Liquid bridging at somewhat regular intervals creates resonance in the feed streams. The effects of numerical decisions and geometry permutations were elucidated. The focus now shifts to compressible 3-D computational models so that geometric parameters, modeled domain size, and non-Newtonian slurry viscosity can be more elaborately explored. While companion studies considered circumferential angles less than 45°, specific attention in this work is given to the circumferential angles larger than 45°, the slurry annular dimension, and how this annular dimension interacts with inner nozzle retraction (pre-filming distance). Additional metrics, including velocity point spectral analyses, are investigated. Two-stream experimental studies are also computationally studied.
Multiple conclusions were drawn. Narrower annular slurry passageways yielded a thinner slurry sheet and increased injector throughput, but the resulting droplets were actually larger. Unfortunately the effect of slurry sheet thickness could not be decoupled from another important geometric permutation; injector geometry physical constraints mandated that, in order to thin the slurry sheet, the thickness of the lip which separates the inner gas and slurry had to be increased accordingly. Increased lip thickness reduced the interfacial shear and increased the thickness of the gas boundary layer immediately adjacent to the slurry sheet. This suppressed the sheet instability and reduced the resulting liquid breakup. Lastly, velocity point correlations revealed that an inertial subrange was difficult to find in any of the model permutations and that droplet length scales correlate with radial velocities.
As anticipated, a higher viscosity resulted in larger droplets. Both the incremental impact of viscosity and the computed slurry length scale matched open literature values. Additionally, the employment of a full 360° computational domain produced a qualitatively different spray pattern. Partial azimuthal models exhibited a neatly circumferentially repeating outer sheath of pulsing spray ligaments, while full domain models showed a highly randomized and broken outer band of ligaments. The resulting quantitate results were similar especially farther from the injector; therefore, wedge models can be used for screening exercises. Lastly, droplet size and turbulence scale predictions for two external literature cases are presented.
Effect of Time Dependent Excitation Signals on Gating in Nanofluidic Channels
Authors: Boone C. , Fuest M. , Wellmerling K. , Prakash S. 
Published: March 2016

Nanofluidic field effect devices feature a gate electrode embedded in the nanochannel wall. The gate electrode creates local variation in the electric field allowing active, tunable control of ionic transport. Tunable control over ionic transport through nanofluidic networks is essential for applications including artificial ion channels, ion pumps, ion separation, and biosensing. Using DC excitation at the gate, experiments have demonstrated multiple current states in the nanochannel, including the ability to switch off the measured current; however, experimental evaluation of transient signals at the gate electrode has not been explored. Modeling results have shown ion transport at the nanoscale has known time scales for diffusion, electromigration, and convection. This supports the evidence detailed here that use of a time-dependent signal to create local perturbation in the electric field can be used for systematic manipulation of ionic transport in nanochannels.
In this report, sinusoidal waveforms of various frequencies were compared against DC excitation on the gate electrode. The ionic transport was quantified by measuring the current through the nanochannels as a function of applied axial and gate potentials. It was found that time varying signals have a higher degree of modulation than a VRMS matched DC signal.
Influence of Materials Properties on the Irradiation Behavior of U-10Mo Monolithic Mini-Plates
Authors: Mohamed Walid , Roh Hee Seok 
Published: March 2016

The DOE/NNSA Conversion [1] Program in the US aims to minimize the use of high enrichment uranium in civilian applications. This initiative is being approached by converting research and test reactors from the use of highly enriched uranium (HEU) to low enrichment uranium (LEU, <20% 235U) with high density of uranium to achieve stable operation of converted reactors. Among variety of fuel materials investigated to serve in the conversion process, U-Mo based alloys have shown stable and acceptable swelling response under typical operation conditions of research and test reactors.
For the conversion of high performance research reactors, a large number of irradiation experiments were conducted to evaluate the mechanical behavior of the U-10Mo monolithic mini-plate; however, it is difficult to investigate all design and operation variables with potential impact on the irradiation behavior of the fuel experimentally.
Thus, this study performed Finite Element Analyses (FEA) on a 3-D monolithic plate by changing material properties of components. The material properties considered in this study included thermal, mechanical, and irradiation specific properties of the fuel, cladding, and liner. Among FEA results, higher Young’s modulus of cladding material caused a significant decrease in all stress values in the three sections of the monolithic mini-plate. On the other hand, variation in the Young’s modulus of Zr-liner showed the minimal effect on the overall mechanical response of the monolithic mini-plate. Results showed that increasing the yield stress of the cladding material directly caused a increase in the maximum stress observed in the cladding section by almost 40 %. Considering the thermal properties of materials in the monolithic plate, maximum and minimum stress in fuel foil were found to either increase or decrease in proportional with the coefficient of thermal expansion of the fuel material. However, variation in the coefficient of thermal expansion in the cladding section caused a remarkable increase in peak stresses in the fuel foil.
While mechanical and thermal properties of the foil, liner, and cladding sections are known, other irradiation-dependent properties such as coefficient of irradiation creep of U-10Mo are not firmly determined to date. The mechanical response of L1P756 is being simulated with different values of the coefficient of irradiation creep and the observed “bulging” in the plate will be compared to available post-irradiation measurements. Thus, it will be possible to determine an accurate value of irradiation creep coefficient of U-10Mo which in turn would allow predicting its mechanical behavior under different irradiation conditions.
Experimental Investigation on Compact Heat Exchanger in Aluminum Foam
Authors: Cirillo Luca , Manca Oronzio , Marinelli Lorenzo , Nardini Sergio 
Published: March 2016

In this paper an experimental investigation on forced convection in a compact heat exchanger made up with an aluminum foam plate of 212.5mm × 212.5mm with a thickness of 40 mm and a single array with five circular tubes is presented. The foam has a porosity of 0.93 with 20 pores per inch and the tubes in aluminum have internal and external diameters equal to 9.5 mm and 12.5 mm. The test rig consists of an open air channel and a closed water cycle and the aluminum foam plate is placed inside the channel. The performances of the compact heat exchanger are evaluated for assigned hot water mass flow rate and different hot water inlet temperatures and air mass flow rate.
Results are given in terms of heat transfer rates and pressure drops as a function of air velocity and Reynolds numbers. The evaluation of dimensionless, thermal resistance, Colburn factor and Nusselt number is performed for different air mass flow rates and hot water inlet temperatures. The performance evaluation criteria is considered in terms of ratio between the heat transfer rate inside the heat exchanger and the pumping power of the air fan.
Development of an Electromagnetic Active Engine Mount
Authors: Vahdati Nader , Heidari Somayeh 
Published: March 2016

Engine mounts need to satisfy three design requirements: (1) firmly support engine weight, (2) isolate structure from the engine’s noise and vibration, and (3) control engine motion when large shocks or engine resonances are present. In addition to these three criteria, which are common for designing all types of engine mounts (passive, semi-active, and active), two more design requirements need to be satisfied for active engine mounts. First, they should be designed such that if there is any malfunction with the actuator, the controller, or the sensors, the active engine mount should still safely operate as a passive mount. Second, the power consumption, the size and weight of the required actuator and its controller should be kept as low as possible.
The current paper aims to present an active hydraulic (or fluid) engine mount design by using an electromagnetic actuator and capacitive circuit such that it is able to act as a passive mount, semi-active mount, and an active mount. In addition, the presented design has the capability to be converted to a damper as and when needed. The multi-functional capability of the proposed engine mount design (passive, semi-active, active, and damper) distinguishes the current design from the previously designed active engine mounting systems, and this multi-functional capability is explained in the paper.
The proposed design consists of a conventional passive hydraulic (fluid) mount, an electromagnetic actuator (voice coil) and a capacitive circuit. The voice coil is placed in the lower chamber of the passive hydraulic mount and it can change the volumetric stiffness of the bottom chamber actively such that the engine mount has low dynamic stiffness in a wide range of frequencies. The capacitive circuit is paralleled with the voice coil and in situations when large shock inputs are present; it adds capacitance to the electromagnetic circuit and changes the characteristics of the mount from an isolator to a damper.
Since the active engine mount design of this paper involves several energy domains, bond graph modeling technique is used for mathematical modeling. MATLAB simulation results are shown for an automotive application and the performance of the proposed active engine mount design is evaluated as an isolator and as a damper. Finally, an adaptive controller, based on Filtered-X LMS algorithm, is proposed and its performance is investigated.
The proposed design can eliminate transmitted force from the engine to the structure in a frequency range of 15 Hz to 125 Hz.
Mild Traumatic Brain Injury From Repeated Low-Level Blast Exposures
Authors: Wong Jessica M. , Halberstadt Adam L. , Sainz Humberto A. , Mathews Kiran S. , Chu Brian W. , Ng Laurel J. , Chan Philemon C. 
Published: March 2016

Recent studies on military breachers in training environments suggest that there are neurocognitive risks from exposure to repeated low-level blasts. However, the dose accumulation effects from multiple low-level blast exposures and their relation to mild traumatic brain injury (mTBI) are not well understood. This paper presents a controlled neurobehavioral study of behavioral effects from repeated low-level blasts delivered at ten second intervals using a rat model.
A custom designed shock tube was developed to deliver repeated low-level blasts to rats at short intervals on the order of seconds. A total of 192 rats were divided into three cohorts of 64 for testing. Each cohort was exposed to a different blast intensity (7.5, 15, or 25 psi reflective pressure with durations <0.25 ms), and each cohort was further divided into four levels of blast repetition (0, 5, 10, or 15 repeats). Shock tube blasts were directed at the rat’s head, and startle with prepulse inhibition (PPI) and fear learning and extinction behavioral tests were performed to evaluate the blast effects.
Behavioral testing results showed that repeated low-level blasts can affect PPI and contextual fear recall. PPI was not affected by repeated exposures to 7.5 psi blasts, but repeated 15 and 25 psi blasts disrupted PPI. All cohorts showed significant fear learning, but the highest blast group (25 psi, 15 repeats) had disruptions in spatial memory recall. None of the cohorts showed effects on cued fear recall or fear extinction and retention. The data collected are being used in continuous research to understand how the behavioral changes relate to mTBI, and how these animal tests can be scaled and modeled to interpret possible outcomes for humans.
Processing Effects on Formation of Microvoids and Hydraulic Fluid Absorption of Quartz/BMI Laminates
Authors: Hurdelbrink Keith R. , Anderson Jacob P. , Siddique Zahed , Altan M. Cengiz 
Published: March 2016

Bismaleimide (BMI) resin with Quartz (AQ581) fiber reinforcement is desirable for systems requiring a high glass transition temperature, low dielectric properties, and high laminate mechanical properties. These properties make quartz/BMI an ideal composite material for complex aerospace structures, and are currently being used in various aircraft engine cowlings and radomes. In addition to moisture absorption, quartz/BMI composite laminates are often exposed to different types of hydraulic fluid contaminants, which may lead to anomalous absorption behavior over the service life of the composite structure. Variations in laminate processing conditions, such as prepreg preconditioning and fabrication cure pressure, can have a significant effect on microstructural features of fiber-reinforced composites. Microstructural features, such as fiber volume fraction and void content, can influence mechanical properties and long term absorption of moisture or other liquid contaminants.
In this paper, the process-induced microstructure and hydraulic fluid absorption behavior of quartz/BMI laminates are presented. The laminates are fabricated from preconditioned prepregs and cured at different pressures to generate different levels of microvoids, while keeping the fiber volume fraction constant. Location, size and morphology of microvoids are investigated via SEM images obtained from laminates cured at different processing conditions. Composite samples were prepared and fully-immersed in hydraulic fluid at room temperature, and were not subjected to any prior degradation. The laminate samples immersed in hydraulic fluid exhibited clear non-Fickian absorption behavior, which was successfully predicted by the one-dimensional Hindered Diffusion Model (HDM). The degree of non-Fickian absorption behavior, or hindrance coefficient (μ), ranged from 0.30 to 0.72. Model prediction indicates that as the fabrication pressure increased, the maximum fluid content (M∞) decreased considerably. Additionally, a reduction in maximum fluid content was observed when lower relative humidity environments were used for prepreg preconditioning. A discernable difference was not observed in the absorption dynamics when the prepregs were preconditioned at greater than 70% relative humidity.
How Inclusive is Abenomics?
Authors: Aoyagi Chie , Ganelli Giovanni , Murayama Kentaro 
Published: March 2016

We assess the ongoing reform efforts in Japan in terms of inclusive growth. We use prefectural level panel data to regress a measure of inclusive growth, and its components of both average income growth and income inequality, on macroeconomic and policy variables. Our analysis suggests that achieving the Bank of Japan’s 2% inflation target has a positive effect on average income growth, but an adverse effect on income equality. In contrast, achieving higher female labor participation, lower duality, and larger labor input — which are included in the package of structural reforms planned under Abenomics — is found to be effective in fostering inclusive growth. While implementation of those policies can improve higher average income growth, only the female labor participation is found to improve the equality as well. The main policy implication of our analysis is that full implementation of structural reforms — especially labor market reforms — is necessary to both foster growth and increase equality.
On-Sky Tests of a High-Power Pulsed Laser for Sodium Laser Guide Star Adaptive Optics
Authors: Otarola Angel , Hickson Paul , Gagné Ronald , Bo Yong , Zuo Junwei , Xie Shiyong , Feng Lu , Rochester Simon , Budker Dmitry , Shen Shixia , Xue Suijian , Min Li , Wei Kai , Boyer Corinne , Ellerbroek Brent , Hu JingYao , Peng Qinjun , Xu Zuyan 
Published: March 2016

We present results of on-sky tests performed in the summer of 2013 to characterize the performance of a prototype high-power pulsed laser for adaptive optics. The laser operates at a pulse repetition rate (PRR) of 600–800[Formula: see text]Hz, with a 6% duty cycle. Its coupling efficiency was found to be, in the best test case (using 18[Formula: see text]W of transmitted power), [Formula: see text] photons s[Formula: see text] sr[Formula: see text] atom[Formula: see text] W[Formula: see text] m2 when circular polarization was employed and [Formula: see text] photons s[Formula: see text] sr[Formula: see text] atom[Formula: see text] W[Formula: see text] m2 with linear polarization. No improvement was seen when D[Formula: see text] repumping was used, but this is likely due to the relatively large laser guide star (LGS) diameter, typically 10 arcsec or more, which resulted in low irradiance levels. Strong relaxation oscillations were present in the laser output, which have the effect of reducing the coupling efficiency. To better understand the results, a physical modeling was performed using the measured pulse profiles and parameters specific to these tests. The model results, for a 10 arcsec angular size LGS spot, agree well with the observations. When extrapolating the physical model for a sub-arcsecond angular size LGS (typical of what is needed for a successful astronomical guide star), the model predicts that this laser would have a coupling efficiency of 130 photons s[Formula: see text] sr[Formula: see text] atom[Formula: see text] W[Formula: see text] m2, using circular polarization and D[Formula: see text] repumping, for a LGS diameter of 0.6 arcsec Full Width at Half Maximum (FWHM), and free of relaxation oscillations in the 589 nm laser light.
A INTERNAÇÃO PSIQUIÁTRICA COMPULSÓRIA DE UM FAMILIAR UTILIZADA COMO MEDIDA PROTETIVA A IDOSOS
Authors: Ramos Priscila Freitas , Brito Cristiane Miryam Drumond de 
Published: March 2016

A internação psiquiátrica é polêmica, principalmente quando não há o consentimento do sujeito. Constata-se, ainda na contemporaneidade, a internação psiquiátrica compulsória (IPC) como medida protetiva setorial específica de proteção à violação de direitos da pessoa idosa. Este artigo faz uma análise documental de processos civis do Ministério Público nos quais houve internações psiquiátricas compulsórias de usuários de álcool e outras drogas como medida específica de proteção à violação de direitos da pessoa idosa em um município de médio porte no interior do Estado de São Paulo. A análise foi realizada à luz das políticas públicas de saúde e de saúde mental e da Constituição Federal. A proteção do idoso é estabelecida via retirada do sujeito agressor de seu domicílio. Não foram verificadas, nos processos, ações da rede de cuidados intersetoriais garantidos nas políticas públicas atuais como procedimento prévio à IPC.