bluuebunny/crossref_metadata_2025 huggingface dataset:
Materials Printing Using Electrospray
Authors: Brown Nicholas A. , Gladstone Jessica N. , Chiarot Paul R.
Published: March 2015

In an electrospray, large electric potentials are used to generate a spray of highly charged droplets. Colloidal dispersions, consisting of nanoparticles in a volatile solvent, can be atomized using electrospray. Printing occurs by directing the emitted droplets towards a target substrate. The solvent evaporation is rapid and dry nanoparticles are produced before reaching the surface. Electrospray imparts an excess electric charge on to the emitted particles. The mutual coulombic interaction between the particles governs their transport and ultimately the microstructure of the printed deposit. In this study, we investigate the structure of nanoparticle ink deposits printed using electrospray. Electrospray offers enhanced control over the microstructure of printed nanomaterial deposits compared to traditional printing techniques. This has significant implications for the manufacturing of flexible electronic and photonic devices.
Design of Beam Surface Displacement Sensors
Authors: Thomas Rohan , Zahui Marcellin
Published: March 2015

PolyVinyliDene Fluoride (PVDF) film is used in this work to develop surface displacement sensors for vibrating simply supported, clamped, and cantilever beams. The constant shape PVDF film is bonded to the surface of the beam spanning the entire beam length. Bands parallel to the width of the beam are etched on the film to create multiple separate sections of the sensor. The individual output charge of the sensor sections is proportional to the slope of the beam lateral displacement curve of that patch. The actual beam surface displacement curve is calculated from these slopes. Theoretical analysis and numerical simulation show that the proposed sensor can be used to effectively measure the lateral vibration displacements of prismatic beams with various boundary conditions. However the accuracy of the measurement is closely related to the number of sensor sections and thus, relatively large number of channels is required for accurate measurements.
Two-Way Fluid-Structure Coupling in Vibration and Damping Analysis of an Oscillating Hydrofoil
Authors: Liaghat T. , Guibault F. , Allenbach L. , Nennemann B.
Published: March 2015

Fluid-structure interaction (FSI) and unavoidable vibrations are important characteristics in the operation of hydropower structures and must be taken into account in the analysis and design of such equipment. Hydrodynamic damping influences the amplitude of vibrations and is directly related to fatigue problems in hydraulic machines which are of great importance. The aim of this study is to investigate the coupled effects of flowing fluid on a simplified hydrofoil by using three-dimensional two-way fluid-structure interaction modeling, in order to determine its importance in predicting vibration amplitudes and damping. The effect of considering different flow velocities is also investigated in the present study. The results of this research are compared with those obtained from experiments done by ANDRITZ [1]. The influences of mesh size and time step are also studied. Our results indicate that considering FSI in predicting the frequencies of the fluctuating fluid forces in practical problems might be ignored if the main concern of the analysis is to check the possibility of resonance. However, FSI must be included in the modeling when we aim to predict the influence of the fluid on the damping behavior in the hydrofoil vibration.
Dynamic Modeling and Slippage Analysis in Object Manipulation by Soft Fingers
Authors: Fakhari Amin , Keshmiri Mehdi , Keshmiri Mohammad
Published: March 2015

In this paper, dynamic modeling and slippage analysis of a three-link soft finger manipulating a rigid object on a horizontal surface is studied. In order to integrate the dynamics of soft tip with the finger linkage, power-law model and a linear viscous damper are used to model the elastic behavior and damping effect of soft tip respectively. Because of the enlarged contact area in the soft contact, a frictional moment can be exerted at the contact interface along with the normal and tangential forces. Furthermore, because of planar motion of object, frictional forces and moment are applied in the contact of object and ground. Therefore, friction limit surface is used as a mapping between contact forces/moment and sliding motions in both contacts. Instead of using equality and inequality equations of frictional contact conditions, a method is proposed to describe different states of the contact forces and moment by a single second-order differential equation with variable coefficients. This kind of formulation of the system dynamics facilitates the design of a controller to cancel the undesired slippage occurs between the soft tip and object during the manipulation.
Nonlinear Forced Vibration of a Beam-Type Resonator With Attached Eccentric Mass
Authors: Hassanpour Pezhman A.
Published: March 2015

In this paper, the nonlinear model of an asymmetric micro-bridge resonator with an attached eccentric mass is investigated. The resonator is treated using the Euler-Bernoulli beam theory. The attached mass represents the electrostatic comb-drive actuator in micro-electromechanical applications. The center of mass of the actuator is assumed to be off the neutral axis of the beam. The governing equations of motion are derived assuming that a concentrated harmonic force is applied to the attached mass. The nonlinear forced vibration of the system is studied using the method of multiple scales. It has been demonstrated that the eccentricity of the mass may lead to different types of nonlinear resonance, e.g., superharmonic and internal resonance. The end application of the structure under investigation is in resonant sensing and energy harvesting applications.
Dynamic Modeling of Space Electrodynamic Tether System Using the Nodal Position Finite Element and Symplectic Integration
Authors: Li GangQiang , Zhu Zheng H.
Published: March 2015

In paper, we build up a simulation program using the nodal position finite element method for the dynamic analysis of the electrodynamic tether system; the model equation is derived from the principle of virtual work. The aerodynamic drag force, gravity force and electrodynamic force are considered. The following models are used, respectively. The NRLMSISE-00 (NRL mass spectrometer, incoherent scatter radar extended model) for the atmosphere density, EGM-2008 (Earth Gravity Model) for the earth gravity field, IGRF-2010 (International Geomagnetic Reference Field) for the earth geomagnetic field, and the IRI-2011 (International Reference Ionosphere model) for the plasma electron density. Two simplified cases of boundary condition are assumed to the governing equation of induced current and voltage, one is for giving the current of anode point just as an input parameter, and the voltage drop in the negative segment is out of consideration; the other one is called full power condition. The program is verified by considering conservative force in the circular orbit, its result shows that the nodal position finite element method is suitable for the long term simulation.
Bond Graph Modeling and Simulating of 3 RPR Planar Parallel Manipulator
Authors: Yin Cheng , Jian Shengqi , Faghih Md. Hassan , Islam Md. Toufiqul , Rolland Luc
Published: March 2015

A 3-RPR planar parallel robot is a kind of planar mechanisms, which can work at high speed, with high accuracy and high rigidity. In this paper, a multi-body bond graph system will be built for the 3-RPR planar parallel manipulator (PPM), along with 3 PID controllers which give commands to 3 DC motors respectively. The advantage of bond graphs is that they can integrate different types of dynamics systems, the manipulator, the control and the motor can be modelled and simulated altogether in the same process. Bond graph will be established for each rigid body with body-fixed coordinate’s reference frames, which are connected with parasitic elements (damping and compliance) to each other. The PID set-point signals are generated by the explicit inverse kinematic equations. The 3 prismatic lengths constitute the measured feedback signals. In order to make the end-effector reach the ideal position with target orientation, the three links should reach the target lengths simultaneously. In this study, the dynamics simulation of 3-RPR PPM is conducted after building the bond graph system. As the 3 motors are working simultaneously and independently, the end-effector will arrive to the expected position. Finally, the bond graph and control system are validated with the compiled results and 3D animation. Force plot and torque plot will be generated as dynamics performance. Moreover, kinematics of manipulators are also calculated using bond graph. Eventually, bond graphs are shown to be effective in solving not only dynamic but also kinematic problems.
Effect of Head Weight on the Biomechanics of a Cervical Spine Under Extension and Flexion Moments
Authors: Mesfar Wissal , Moglo Kodjo
Published: March 2015

The determination of head and neck biomechanics is one of the keys for deep understanding of impairments in neck function and cervical spine pathologies. Finite element models are a valuable tool to perform parametric studies. In this study, we aim to investigate the effect of a 40N head weight on the biomechanics of the head and neck complex under flexion-extension moments. The loading is applied to the centre of mass of the head and the first thoracic vertebra is fixed. Our predictions show that the kinematics and the load distribution at the facet joints were altered significantly with considering of the head weight under the flexion and extension movements. Our investigations indicate the substantial role of the head weight on the biomechanical behavior of the cervical spine and suggest its consideration in comparing the models predictions with the measurements.
A Bi-Frequency Co-Linear Array Transducer for Biomedical Ultrasound Imaging
Authors: Wang Zhuochen , Li Sibo , Liu Ruibin , Geng Xuecang , Jiang Xiaoning
Published: March 2015

Ultrasound imaging with high resolution and large field of depth has been increasingly adopted in medical diagnosis, surgery guidance and treatment assessment because of its relatively low cost, non-invasive and capability of real-time imaging. There is always a tradeoff between the resolution and depth of field in ultrasound imaging. Conventional ultrasound works at a particular frequency, with −6 dB fractional bandwidth of < 100%, limiting the resolution or field of depth in many ultrasound imaging cases.

In this paper, a bi-frequency co-linear array covering a frequency range of 5 MHz-20 MHz was investigated to meet the requirements of resolution and depth of field for a broad range of ultrasound imaging applications. As a demonstration, a 31-element bi-frequency co-linear array was designed and fabricated, followed by element characterization and real time sectorial scan (S-scan) phantom imaging using a Verasonics system.
Development of a Self-Oscillating Mechanical Model to Investigate the Biological Response of Human Vocal Fold Fibroblasts to Phono-Mimetic Stimulation
Authors: Latifi Neda , Heris Hossein K. , Kazemirad Siavash , Mongeau Luc
Published: March 2015

The human vocal folds are subjected to complex dynamic biomechanical stimulation during phonation. The aim of the present study was to develop and evaluate an airflow-induced self-oscillating mechanical model, i.e., a bioreactor, which mimics the geometry and the mechanical microenvironment of the human vocal folds. The bioreactor consisted of two composite synthetic vocal fold replicas loaded into a custom-built airflow supplied tube. A cell-scaffold mixture was injected into cavities within the replicas. The folds were phonated using a variable speed centrifugal blower for two hours a day over a period of seven days. The static and dynamic subglottal pressures and the dynamic supraglottal pressure were monitored. A similar bioreactor without mechanical excitation was used as positive control. The cell-scaffold mixture was harvested for cell viability and collagen type I immunohistochemistry tests seven days after injection. The flow-induced self-oscillations of the vocal fold replicas were shown to produce mechanical excitations that are typical of those in the human vocal fold lamina propria during phonation. The results confirmed that human vocal fold fibroblasts survived inside the present bioreactor, and maintained cellular functions of protein production.
Numerical Modeling of Wave Soldering in PCB
Authors: Arcipreste Bruno , Soares Delfim , Ribas Luis , Teixeira José Carlos
Published: March 2015

Manufacturing of electronic boards (commonly referred as PCB) is a highly automated process that requires an accurate control of the various processing variables. Amongst the soldering processes, wave soldering is one of the most often used. In this, the various electronic components are provisionally inserted onto the PCB, and a low velocity jet of melted solder is directed to the moving board. Due to capillarity effects the solder adheres to the component/board interface and the process is completed. This methodology is most often used for small components. The adjusting of the operating parameters (solder nozzle orientation and velocity) is often carried out on a trial and error basis resulting in a time consuming process that is at odds with the increasing demand for smaller production series that the electronics industry is faced with.

In addition the number of defects (mostly from missing components that are washed away by the impacting jet) is more likely to occur when thinner substrates are used in the PCB manufacturing.

The present paper describes the application of a Computational Fluid Dynamics model to describe the interaction of the solder jet with the PCB and the integrated circuits. The model includes the conservation equations for mass, momentum and energy in a transient time frame. The jet and surrounding ambient atmosphere are modeled as two separate fluids and the interface is tracked by a VOF model. By adjusting the computational mesh refinement the interface is captured with accuracy. The drag forces occurring in the various components are computed from the pressure data field. The model allows the optimization of the wave operating parameters as a function of the component type of and its layout in the PCB.
Synthesis and Characterization of Hybrid Actuator Based on Polypyrrole and SMA
Authors: Potnuru Akshay , Tadesse Yonas
Published: March 2015

This paper presents initial investigation on a hybrid artificial muscle actuator combining two actuation technologies, based on conductive polymers and shape memory alloys (SMAs). Polypyrrole is used as the conductive polymer muscle and nickel-titanium as shape memory alloy to make the composite muscle system. Depending on the geometry of the actuator, doped polypyrrole exhibits large strain, consuming less voltage and current; whereas shape memory alloy generates large stress (force), consuming high power (high current). Helically wound coil structure was chosen as the shape of the composite actuator in this study. The polypyrrole is synthesized on the surface of the Ni-Ti shape memory alloy wire, wound around a core gold coated polylactide fiber (PLA). Preliminary results on the performance and synthesis conditions of the composite actuator will be presented for various applications under different conditions.
Design for Rapid Prototyping, Manufacturing and Tooling: Guidelines
Authors: Zaragoza-Siqueiros Jorge , Medellín-Castillo Hugo I.
Published: March 2015

The design is an important step in the development of a product or component; many important decisions affecting the final cost and manufacturability of the product are made at this stage. Therefore several design guidelines for manufacturing and assembly (DFMA), ergonomics, maintenance, standardization, against corrosion, risk minimization, recycling, among others, have been proposed in the literature. The aim of these design guidelines is to provide designers with guidance to reduce costs, manufacturing difficulties, and increase the lifetime of a product. The use of new manufacturing techniques such as rapid prototyping, manufacturing and tooling (RPM&T) are increasing in the industry to speed up the design and development of products. However, there are not design guidelines for these emerging technologies.

This paper focuses on establishing design for rapid prototyping, manufacturing and rapid tooling (DFRPM&T) guidelines. These guidelines are based on reviews and analysis of the operating principle, materials, capabilities and limitations of current commercially available RPM&T technologies. The proposed design guidelines are classified into three types: (1) design for rapid prototyping according to the geometric characteristics of the part, (2) part quality requirements, and (3) part costs and sustainability. Important features such as support structures, overhangs, rounded, knife edges, part orientation, path planning, distortion, shrinkage, warping, accuracy, stability, part post-processing, part cost and environmental resistance are considered in the proposed design for RPM&T guidelines.
A Novel Method for Calculation Gear Tooth Stiffness for Dynamic Analysis of Spur Gears With Asymmetric Teeth
Authors: Karpat F. , Dogan O. , Ekwaro-Osire S. , Yuce C.
Published: March 2015

Recently, there have been a number of research activities on spur gears with asymmetric teeth. The benefits of asymmetric gears are: higher load capacity, reduced bending and contact stress, lower weight, lower dynamic loads, reduced wear depths on tooth flank, higher reliability, and higher efficiency. Each of the benefits can be obtained through asymmetric teeth designed correctly. Gears operate in several conditions, such as inappropriate lubrication, excessive loads and installation problems. In working conditions, damage can occur in tooth surfaces due to excessive loads and unsuitable operating conditions. One of the important parameters of the tooth is stiffness, which is found to be reduced proportionally to the severity of the defect by asymmetric tooth design as described in this paper. The estimation of gear stiffness is an important parameter for determining loads between the gear teeth when two sets of teeth are in contact. In this paper, a 2-D tooth model is developed for finite elements analysis. A novel formula is derived from finite element results in order to estimate tooth stiffness depending on the tooth number and pressure angle on the drive side. Tooth stiffness for spur gears with asymmetric teeth is calculated and the results were compared with well known equations in literature.
Dynamic Test for Human Knee Ligament Structure Assessment
Authors: Caruntu Dumitru I. , Granados Eduardo
Published: March 2015

In this paper a nonlinear human knee dynamics model to include viscoelastic ligaments is proposed. The knee model is two dimensional and include tibia, femur, ligamentous knee structure, and knee cartilages. The model is used to investigate the influence of ligamentous viscoelastic properties on dynamic testing of human knee. An exercise in which the femur is pinned at the hip in a sitting position, and tibia in a vertical position is actuated by a vertical harmonic force at various frequencies is proposed. The viscoelastic model of ligaments shows better predictions on the knee dynamic testing.
Development of Robotics Simulation Using Creo 2.0
Authors: Somani Shubham , Jain Anshul , Savsani Vimal , Savsani Poonam
Published: March 2015

Simulation of robot systems is getting very popular, especially with the lowering cost of computers. The robotic arm is presumably the most mathematically complex for the dynamic and kinematic analysis. The purpose of this paper is to build a simulation framework for a 3R robotic arm using PTC Creo Parametric 2.0 and also to identify its advantages and disadvantages for such analysis. Trajectory of the robotic arm is optimized by considering the shortest path as an objective function between the initial and final position which results in straight line motion using an effective optimization technique known as Teaching learning based optimization (TLBO). Intermediate positions of the optimized results are taken as an input for the simulation of the 3R robotic arm in PTC Creo Parametric 2.0. The results obtained by using TLBO and PTC Creo Parametric 2.0, such as angular positions, joint velocities and joint accelerations are compared based on RMS errors. The verification of the obtained results by both the methods allows us to qualitatively evaluate, underline the rightness of the chosen model and to get the right conclusions.
Modeling and Velocity Control of A-Shape Microrobot With Adaptive Neural Network Controller
Authors: Nojoumian M. A. , Shirazi M. Jahromi , Vossoughi G. R. , Salarieh H.
Published: March 2015

Design and control of micro robots have been one of the interesting fields in robotics in recent years. One class of these micro robots is the legged robots. Various designs of legged robots have been proposed in the literature. All designs rely on friction for locomotion. In this paper dynamic model of a planar two-legged micro robot is presented using Luger friction model, and an adaptive neural controller used to control the robot to improve robustness and velocity of the robot.

As mentioned earlier, friction plays an important role in locomotion of the legged robots. However, especially in legged micro robots, it is difficult to model the frictional force correctly since environmental disturbances like dust and changes in shape of the test bed can significantly alter its value. Therefore, one needs to design a controller that adapt to new condition and had enough robustness so one chooses neural network controller. Result show that with updating weight of neural network robot could follow desired trajectory, and with change in friction coefficient training time was low enough to update weight at each step.
Moisture Absorption of Composite Sandwich Structures
Authors: Coburn Todd
Published: March 2015

It is widely understood that moisture can have a detrimental effect on the strength of composite structures. Traditional analysis often focuses on the effects to solid laminates or on the facesheets of composite sandwich structures. However, this focus is often not sufficient to ensure material strength and performance. It has been found that moisture effects on sandwich structures can also have a detrimental effect on secondary failure modes such as shear crimping and facesheet wrinkling, and that these effects can be significant, especially at temperature. A proper assessment of moisture effects on composite sandwich structures involves five key components: development of moisture diffusion constants, prediction of structural moisture levels, development of material allowables at predicted moisture levels, analysis of structure, and modification of the design, when warranted. This paper describes each component of this process, and introduces a simple algorithm to integrate the analysis.
Real Time Simulation for High Fidelity Multibody Dynamics and Mechatronic Systems
Authors: Prescott William
Published: March 2015

This paper will investigate the use of large scale multibody dynamics (MBD) models for real-time vehicle simulation. Current state of the art in the real-time solution of vehicle uses 15 degree of freedom models, but there is a need for higher-fidelity systems. To increase the fidelity of models uses this paper will propose the use of the following techniques: implicit integration, parallel processing and co-simulation in a real-time environment.
Nonlinear Analysis of Rub Impact in a Three-Disk Rotor and Correction via Bearing and Lubricant Adjustment
Authors: Weaver Brian K. , Zhang Ya , Clarens Andres F. , Untaroiu Alexandrina
Published: March 2015

Rubbing between rotating and stationary surfaces in turbomachinery can result in catastrophic failures if not caught quickly. Removing the rub impact can then often require time consuming and expensive solutions including field balancing or magnetic bearing systems. However, simple changes in bearing dynamics via bearing and lubricant adjustment could provide for a faster and cheaper alternative. In this work, a three-disk rotor was examined analytically for nonlinear rotordynamic behavior due to an unbalance-driven rub. The rotordynamic solution was obtained using nonlinear and steady state finite element models to demonstrate the effect of the rub impact on the dynamic response of the machine. A thermoelasto-hydrodynamic (TEHD) model of tilting pad journal bearing performance was also used to study the possible removal of the rub impact by making minor adjustments to bearing parameters including preload, clearance, pad orientation, and lubricant properties. Gas-expanded lubricants, tunable mixtures of synthetic oil and carbon dioxide that have been proposed as a means to provide control in bearing-rotor systems, were also considered for their possible role in controlling the rub. The TEHD model provided a range of bearing inputs to the rotor models in the form of stiffness and damping coefficients. Results from the rotordynamic analyses included an assessment of critical speeds, peak rotor displacements, and vibration characteristics. Individual bearing parameter adjustments were found to have smaller, though still significant effects on the response of the machine. Overall it was found that by adjusting a combination of these bearing parameters that the peak displacement of the rotor could be reduced by large enough amounts to remove the rub impact in the machine, hence providing a simple approach to solving rub impact problems in rotating machinery caused by excessive vibration.
The Unscented Smooth Variable Structure Filter Application Into a Robotic Arm
Authors: Al-Shabi Mohammad , Hatamleh Khaled S.
Published: March 2015

Robotic arms are becoming increasingly popular in industrial applications. However, improving the response and accuracy of robotic arms while reducing their cost has become challenging. The Kalman Filter (KF) has attracted a significant amount of research as it improves the control quality by filtering the feedback signal. On the other hand, KF solution becomes very challenging when the system under study is nonlinear. This work proposes a new online state estimation algorithm that combines the Smooth Variable Structure Filter (SVSF) with the Unscented Kalman Filter (UKF). The proposed method overcomes the limitations of SVSF and UKF in terms of stability and sensitivity to noise. A simulation study is conducted in this paper to demonstrate the results of the proposed method when applied to estimate the states of a PRRR industrial robotic arm.
3D-Modelling and Simulation of Physicochemical Transformations in a High-Pressure Turbine (HPT) of an Aircraft Engine
Authors: Nguyen T. H. , Garnier F.
Published: March 2015

In this work, the 3D design of the stator, rotor of a turbine is performed. A one way coupling between a detailed physicochemical box model and multidimensional Navier-Stokes solver (FLUENT software) is used. Various series of three-dimensional calculations including approximately 500,000 elements are carried out to calculate aero-thermodynamics fields for a first stage of high-pressure turbine of the CFM56 aero-engine. The results show that blades of early turbine stages, directly downstream of combustor are subjected to relatively high levels of unsteadiness generated from complex significant three dimensional shear layers. The latter causes the formation of large-scale turbulent. By consequence, the complex interactions between the geometrical parameters, thermodynamical and chemical processes involving aerosol precursor formation in the turbine are analyzed and investigated.
Cancer Recovery Analysis System
Authors: Balasubramanian Priya , Pradeep Archana , Dileepkumar Deepak , Farris John P. , Jack Hugh
Published: March 2015

Breast cancer is one of the most common types of cancer among women with over 230,000 incidences diagnosed every year. A typical breast cancer surgery might include but is not limited to, biopsies, breast conservation surgery or mastectomies. Moreover, these surgeries usually cause soreness in the shoulder and arms which in turn affect the ability of the patient to perform simple everyday activities.

Lymphedema, another serious side effect of these surgeries, when coupled with radiation therapy, can appear in breast cancer patients during months or even years after the treatment ends. Lymphedema is a condition in which high-protein fluid collects beneath the skin and causes swelling, redness and discomfort. This condition occurs in breast cancer patients when lymph nodes are damaged or removed during the procedures.

Research suggests that early physiotherapy as well as exercises can reduce the risk of lymphedema. Monitoring the progress during these exercises can be a first step in diagnosing lymphedema. Along with better prognosis, the patients can observe the benefits of early diagnosis with insurance coverage, since most insurance companies do not cover treatments associated with advanced stages of lymphedema. The initial stretching workouts, done during recovery, target the range of motion of the shoulder that is affected by the surgery. This range of motion, determined by the severity of the surgery, improves over time. These exercises can then be used to drain the lymph nodes and help retain flexibility in the affected muscles. A monitoring device engineered to provide data about the extent of recovery would be a significant aide to both the patients and healthcare professionals.

The intent of the paper is to introduce a distinctive device that monitors workouts and uses the data as a motivating factor for the patient as well as an early detection system for lymphedema. The device shows the effort that the patient has put for each workout into user friendly real time graphs. Patients and healthcare professionals can then use this data and graphs to identify problem areas in the recovery process. Preliminary tests of this device, which are presented in this paper, showed promising results in accuracy and repeatability as the device calculated and displayed graphs which were a quantified estimation of the range of motion and workout effort of the user.
Head phantoms for transcranial focused ultrasound
Authors: Eames Matthew D. C. , Farnum Mercy , Khaled Mohamad , Jeff Elias W. , Hananel Arik , Snell John W. , Kassell Neal F. , Aubry Jean‐Francois
Published: March 2015

Purpose:

In the ongoing endeavor of fine‐tuning, the clinical application of transcranial MR‐guided focused ultrasound (tcMRgFUS), ex‐vivo studies wlkiith whole human skulls are of great use in improving the underlying technology guiding the accurate and precise thermal ablation of clinically relevant targets in the human skull. Described here are the designs, methods for fabrication, and notes on utility of three different ultrasound phantoms to be used for brain focused ultrasound research.

Methods:

Three different models of phantoms are developed and tested to be accurate, repeatable experimental options to provide means to further this research. The three models are a cadaver, a gel‐filled skull, and a head mold containing a skull and filled with gel that mimics the brain and the skin. Each was positioned in a clinical tcMRgFUS system and sonicated at 1100 W (acoustic) for 12 s at different locations. Maximum temperature rise as measured by MR thermometry was recorded and compared against clinical data for a similar neurosurgical target. Results are presented as heating efficiency in units (°C/kW/s) for direct comparison to available clinical data. The procedure for casting thermal phantom material is presented. The utility of each phantom model is discussed in the context of various tcMRgFUS research areas.

Results:

The cadaveric phantom model, gel‐filled skull model, and full head phantom model had heating efficiencies of 5.3, 4.0, and 3.9 °C/(kW/s), respectively, compared to a sample clinical heating efficiency of 2.6 °C/(kW/s). In the seven research categories considered, the cadaveric phantom model was the most versatile, though less practical compared to the ex‐vivo skull‐based phantoms.

Conclusions:

Casting thermal phantom material was shown to be an effective way to prepare tissue‐mimicking material for the phantoms presented. The phantom models presented are all useful in tcMRgFUS research, though some are better suited to a limited subset of applications depending on the researchers needs.
Wireless magnetothermal deep brain stimulation
Authors: Chen Ritchie , Romero Gabriela , Christiansen Michael G. , Mohr Alan , Anikeeva Polina
Published: March 2015

Exciting nerve cells deep inside the brain

Current techniques to stimulate regions inside the brain need a permanently implanted wire or an optical fiber. Working in mice, Chen
et al.
developed a method to overcome this problem (see the Perspective by Temel and Jahanshahi). They introduced heat-sensitive capsaicin receptors into nerve cells and then injected magnetic nanoparticles into specific brain regions. The nanoparticles could be heated by external alternating magnetic fields, which activated the ion channel–expressing neurons. Thus, cellular signaling deep inside the brain can be controlled remotely without permanent implants.

Science
, this issue p.
1477
; see also p.
1418
Draft Genome Sequence of Halomonas sp. KHS3, a Polyaromatic Hydrocarbon-Chemotactic Strain
Authors: Gasperotti Ana Florencia , Studdert Claudia Alicia , Revale Santiago , Herrera Seitz María Karina
Published: March 2015

The draft genome sequence of Halomonas sp. KHS3, isolated from seawater from Mar del Plata harbor, is reported. This strain is able to grow using aromatic compounds as a carbon source and shows strong chemotactic response toward these substrates. Genes involved in motility, chemotaxis, and degradation of aromatic hydrocarbons were identified.
Two Complete and One Draft Genome Sequence of Nonproteolytic Clostridium botulinum Type E Strains NCTC 8266, NCTC 8550, and NCTC 11219
Authors: Clauwers Charlien , Briers Yves , Lavigne Rob , Michiels Chris W.
Published: March 2015

Group II (gII) nonproteolytic
Clostridium botulinum
strains are a major cause of foodborne botulism outbreaks. Here, we report two complete genome sequences of gII type E strains NCTC 8266 and NCTC 8550 and one draft genome sequence of type E NCTC 11219.
Draft Genome Sequences of Two Strains of Serratia spp. from the Midgut of the Malaria Mosquito Anopheles gambiae
Authors: Pei Dong , Hill-Clemons Casey , Carissimo Guillaume , Yu Wanqin , Vernick Kenneth D. , Xu Jiannong
Published: March 2015

Here, we report the annotated draft genome sequences of two strains of Serratia spp., Ag1 and Ag2, isolated from the midgut of two different strains of
Anopheles gambiae
. The genomes of these two strains are almost identical.
Genome Sequences of Mannheimia haemolytica Serotype A2 Isolates D171 and D35, Recovered from Bovine Pneumonia
Authors: Hauglund Melissa J. , Tatum Fred M. , Bayles Darrell O. , Maheswaran Samuel K. , Briggs Robert E.
Published: March 2015

Here, we report two genomes, one complete and one draft, from isolates of serotype A2
Mannheimia haemolytica
recovered from pneumonic bovine lung.
Complete Genomic Sequence for an Avian Group G Rotavirus from South Africa
Authors: Stucker Karla M. , Stockwell Timothy B. , Nyaga Martin M. , Halpin Rebecca A. , Fedorova Nadia , Akopov Asmik , Ngoveni Harry , Peenze Ina , Seheri Mapaseka L. , Mphahlele M. Jeffrey , Wentworth David E.
Published: March 2015

We report the first complete sequence for an avian group G rotavirus (RVG) genome from Africa, which is the third publically available RVG genome. These RVG genomes are highly diverse, especially in their VP4, VP7, NSP4, and NSP3 segments, indicating that RVG diversity is comparable to that of rotavirus A.
Complete Genome Sequence of Mycoplasma flocculare Strain Ms42
T
(ATCC 27399
T
)
Authors: Calcutt Michael J. , Foecking Mark F. , Heidari Manijeh B. , McIntosh Mark A.
Published: March 2015

Mycoplasma flocculare
is a commensal or low-virulence pathogen of swine. The complete 778,866-bp genome sequence of M. flocculare strain Ms42
T
has been determined, enabling further comparison to genomes of the closely related pathogen
Mycoplasma hyopneumoniae
. The absence of the
p97
and
glpD
genes may contribute to the attenuated virulence of M. flocculare.
Complete Genome Sequences of Influenza A/H1N1 Strains Isolated from Patients during the 2013-2014 Epidemic Season in Finland
Authors: Jalovaara Petri , Mishel Polina , Kallio-Kokko Hannimari , Valkonen Miia , Kantele Anu , Ikonen Niina , Julkunen Ilkka , Kakkola Laura , Kutsaya Anna , Vuorinen Tytti , Mattila Pirkko , Almusa Henrikki , Kainov Denis
Published: March 2015

Here, we report 40 complete genome sequences of influenza A/H1N1 strains isolated from 33 nonhospitalized and 7 hospitalized patients during the 2013-2014 epidemic season in Finland. An analysis of the aligned sequences revealed no oseltamivir-resistant genotypes. As a whole, the recent viruses have drifted from the prototype A/California/7/2009 virus by ca. 1.3%.
Draft Genome Sequences of Five Spore-Forming Food Isolates of Bacillus pumilus
Authors: de Jong Anne , van Heel Auke J. , Montalban-Lopez Manuel , Krawczyk Antonina O. , Berendsen Erwin M. , Wells-Bennik Marjon , Kuipers Oscar P.
Published: March 2015

Here, we report the draft genome sequences of five food isolates of
Bacillus pumilus
, a spore-forming Gram-positive bacterium.
Details behind the dots: How different intensive care units used common and contrasting methods to prevent ventilator associated pneumonia
Authors: Daniel Malcolm , Booth Malcolm , Ellis Kirsteen , Maher Shaun , Longmate Andrew
Published: March 2015

Care bundles promote delivery of effective care and improve patient outcomes. The understanding of how to improve delivery of care bundles is incomplete.

The Scottish Patient Safety Programme is a national collaborative with the aim of improving the delivery of care to patients in acute hospitals in Scotland. Critical care is one of five workstreams in the programme. A programme goal is to reduce incidence of ventilator-associated pneumonia (VAP) to zero or 300 calendar days between events through use of a VAP Prevention bundle. We studied two ICUs participating in this programme. Each ICU had established infection surveillance system prior to the programme starting. Both units had an appreciable incidence of VAP. Initial VAP prevention bundle adherence was low in each ICU (35% and 41%).

Comparing time periods before and after 80% bundle VAP prevention bundle adherence was achieved showed a similar reduction in VAP incidence (from 6.9 to 1.0, and from 7.8 to 1.4/1000 ventilation days). When compared each ICU used common and contrasting approaches to accomplish this improvement.

We describe the five improvement knowledge systems used to improve bundle adherence to bundle elements in each hospital. The insights gained from these front-line clinical teams can be used as a template for improvement efforts in a variety of other healthcare settings.
Association of a lifestyle index with MRI-determined liver fat content in a general population study
Authors: Koch Manja , Borggrefe Jan , Schlesinger Sabrina , Barbaresko Janett , Groth Godo , Jacobs Gunnar , Lieb Wolfgang , Laudes Matthias , Müller Manfred J , Bosy-Westphal Anja , Heller Martin , Nöthlings Ute
Published: March 2015

Background

In prior studies, lifestyle indices were associated with numerous disease end points, but the association with fatty liver disease (FLD), a key correlate of cardiometabolic risk, is unknown. The aim was to investigate associations between a lifestyle index with liver fat content.

Methods

Liver fat was quantified by MRI as liver signal intensity (LSI) in 354 individuals selected from a population-based cohort from Germany. Exposure to favourable lifestyle factors was quantified using an additive score with each factor modelled as a dichotomous trait. Favourable lifestyle factors were defined as waist circumference below 102 (men) or 88 cm (women), physical activity ≥3.5 h/week, never-smoking and a favourable dietary pattern, which was derived to explain liver fat variation. In a cross-sectional study, multivariable adjusted linear and logistic regression was applied to investigate the association between the lifestyle index (range 0–4, exposure) and LSI (modelled as a continuous trait or dichotomised as a FLD indicator variable, respectively).

Results

Individuals with four favourable lifestyle factors (n=9%) had lower LSI values (ß −0.40; 95% CI −0.61 to −0.19) and a lower OR (0.09; 95% CI 0.03 to 0.30) for FLD compared with individuals with zero favourable lifestyle factors (n=10%).

Conclusions

A healthy lifestyle pattern was associated with less liver fat. Prospective studies are warranted.
Management of paraureteral pseudocyst and ureteral avulsion using a subcutaneous ureteral bypass (SUB) system in a cat
Authors: Rossanese Matteo , Murgia Daniela
Published: March 2015

A 1.6‐year‐old male neutered domestic shorthair cat was presented after a road traffic accident with lethargy, anorexia, abdominal pain and inability to jump. On physical examination, a space‐occupying lesion in the left flank was detected. Investigations demonstrated a cavitated fluid‐filled structure in the left retroperitoneal space consistent with a paraureteral pseudocyst (urinoma) secondary to left ureteral rupture. Ventral midline exploratory laparotomy was completed. The urinoma was drained, the damaged ureter ligated and a subcutaneous ureteral bypass (SUB) device was placed under fluoroscopy guidance. On re‐examination at five and nine weeks postoperatively, investigations revealed patency of the device and normal renal function. The use of a SUB allowed ureteral bypass and preserved the injured kidney.
Consumption of açai (Euterpe oleraceaMart.) functional beverage reduces muscle stress and improves effort tolerance in elite athletes: a randomized controlled intervention study
Authors: Carvalho-Peixoto Jacqueline , Moura Mirian Ribeiro Leite , Cunha Felipe Amorim , Lollo Pablo Christiano B. , Monteiro Walace David , Carvalho Lucia Maria Jaeger de , Farinatti Paulo de Tarso Veras
Published: March 2015

The study analyzed the effect of an açai (Euterpe oleracea Mart.) functional beverage (AB) on muscle and oxidative stress markers, cardiorespiratory responses, perceived exertion, and time-to-exhaustion during maximal treadmill running. The beverage was developed as an ergogenic aid for athletes and contained 27.6 mg of anthocyanins per dose. Fourteen athletes performed 3 exercise tests: a ramp-incremental maximal exercise test and 2 maximal exercise bouts performed in 2 conditions (AB and without AB (control)) at 90% maximal oxygen uptake.Blood was collected at baseline and after maximal exercise in both conditions to determine biomarkers. AB increased time to exhaustion during short-term high-intensity exercise (mean difference: 69 s, 95% confidence interval = –296 s to 159 s, t = 2.2, p = 0.045), attenuating the metabolic stress induced by exercise (p < 0.05). AB also reduced perceived exertion and enhanced cardiorespiratory responses (p < 0.05). The AB may be a useful and practical ergogenic aid to enhance performance during high-intensity training.
Pharmacophore modeling and molecular docking studies of acridines as potential DPP-IV inhibitors
Authors: Abu Khalaf R. , Jarekji Z. , Al-Qirim T. , Sabbah D. , Shattat G.
Published: March 2015

Inhibition of dipeptidyl peptidase-IV (DPP-IV) prevents the inactivation of gastric inhibitory polypeptide (GIP) and glucagon-like peptide–1 (GLP-1). This increases circulating levels of active GLP-1 and GIP and stimulates insulin secretion, which results in lowering of glucose levels and improvement of the glycemic control in patients with type 2 diabetes. In this study, pharmacophore modeling and docking experiments were carried out and a series of eight novel 2-ethoxy-6,9-disubstituted acridines (13, 15, and 17a–17f) have been designed and synthesized. Then, these compounds were evaluated for their ability to inhibit DPP-IV. Most of the synthesized compounds were proven to have anti-DPP-IV activity where compound 17b displayed the best activity of 43.8% inhibition at 30 μmol/L concentration. Results of this work might be helpful for further optimization to develop more potent DPP-IV inhibitors.
Molecular characterisation and prevalence of a new genotype of Cyprinid herpesvirus 2 in mainland China
Authors: Li Lijuan , Luo Yangzhi , Gao Zexia , Huang Jian , Zheng Xianghai , Nie Huihui , Zhang Junmei , Lin Li , Yuan Junfa
Published: March 2015

Cyprinid herpesvirus 2 (CyHV-2, species Cyprinid herpesvirus 2) has been confirmed as a causative agent of the acute haematopoietic necrosis disease outbreak in farmed goldfish (Carassius auratus L.) and gibel carp (Carassius auratus gibelio Bloch). In this study, we present the genomic characteristics of a variant CyHV-2 strain (SY-C1) isolated from farmed gibel carp in mainland China and its comparative genomics analysis with the CyHV-2 reference strain ST-J1. Overall, the full-length genome of SY-C1 shares 98.8% homology with that of ST-J1. Sequence comparisons between SY-C1 and ST-J1 indicate that the variations include single-nucleotide mutations, insertions, deletions, and rearrangements, which suggested that SY-C1 is different from ST-J1 and represents a new genotype. Therefore, we propose that the identified CyHV-2 can be divided into 2 different genotypes and be named China genotype (C genotype) and Japan genotype (J genotype) according to their isolation loci. Furthermore, epidemiological surveys indicate that the dominant genotype of CyHV-2 circulating in mainland China is closer to the China genotype than the Japan genotype.
The effect of process condition of the ink-jet printing process on the molten metallic droplet formation through the analysis of fluid propagation direction
Authors: Wu Cheng-Han , Hwang Weng-Sing
Published: March 2015

This study investigated the droplet formation mechanism using simulation analysis under various process conditions of ink-jet printing. Experimentally, the droplet shapes were cataloged in four types with the dwell time of the mono-polar waveform, and used to verify the reliability of the numerical model by finding consistency with the simulated modes of droplet formation. Conventional droplet formation depiction using pressure variation has not been comprehensive; as such, fluid propagating velocity was used to discuss the droplet formation mechanism in this study. Through the analysis of the fluid propagation velocity, a sufficient outward momentum of the fluid at the nozzle and a pulling force to pinch off the liquid thread were found to be essential for generating a single droplet. An insufficient pulling force would lead to undesired droplet shapes. A bipolar waveform can be used to enhance the outward momentum and the pulling force of the fluid, and the improvements in droplet formation were revealed in both the simulation and experiment. Results demonstrate that the analysis from the velocity variation is a useful and essential method when evaluating the droplet formation mechanism.
Entropic force law in the presence of a noncommutative inspired space–time for a solar system scale
Authors: Mehdipour S. Hamid
Published: March 2015

We first study some aspects of a physically inspired noncommutative spherically symmetric space–time based on the Gaussian-smeared mass distribution for a solar system scale. This leads to the elimination of a singularity apparent in the origin of the space–time. Afterwards, we investigate some features of Verlinde’s scenario in the presence of the mentioned space–time and derive several quantities, such as Unruh–Verlinde temperature, the energy, and the entropic force on three different types of holographic screens, namely, the static, the stretched horizon, and the accelerating surface.