bluuebunny/crossref_metadata_2025 huggingface dataset:
Balancing of Flexible Rotors Having Arbitrary Mass and Stiffness Distribution
Authors: Hundal M. S. , Harker R. J.
Published: December 2011

A method for balancing a flexible rotor is developed which is based upon the dynamic response of the rotor in its normal modes as excited by the distributed mass unbalance. The balance corrections are determined by equating the modal components of the corrections to the modal components of the unbalance of the rotor. Methods of balancing individual modes as well as simultaneous balancing in any number of modes are presented. The suggested procedure requires calculation of the normal modes and critical speeds, and measurement of the dynamic amplitude at selected points along the rotor axis.
The Plastic Bending of Beams Considering Die Friction Effects
Authors: Martin G. , Tsang S.
Published: December 2011

This paper describes a theoretical and experimental analysis of the behavior of simple beams bent by a central load while freely supported at each end. Both plane strain and plane stress conditions and the effect of friction at the beam supports are considered. Materials tested are SAE 4130 steel and titanium 6Al-4V alloy. It is concluded that in beams, whose length between supports is at least 25 times their thickness, the load required to effect deflection is increased by the amount required to overcome friction, but does not affect the circumferential strain at midspan. Theoretical methods of analysis correlate well with experimental results and allow the computation of stresses and strains from the beam geometry and true tensile curves of the materials.
Four-Parameter Generalized Compressibility Charts for Nonpolar Fluids
Authors: Hsieh Jui Sheng
Published: December 2011

A series of five generalized compressibility charts for nonpolar and slightly polar substances in the gaseous and liquid states and in the two-phase region is presented. The charts are plots of the compressibility factor Z versus the reduced pressure Pr with the reduced temperature Tr as a parameter. Each chart is for a group of substances with similar values of the critical compressibility factor Zc and the slope of the reduced vapor-pressure curve at the critical point, αc. The use of four independent parameters (Pr, Tr, Zc, and αc) results in an increase in accuracy over existing methods of presenting compressibility charts.
Acceleration Analysis of Spatial Four-Link Mechanisms
Authors: Yang An Tzu
Published: December 2011

Acceleration analysis of a spatial four-link mechanism with one revolute pair and three cylindrical pairs of general proportions is presented here; results are expressed in concise algebraic forms which are well adapted to either manual or programmed computation. It is believed that the method employed in this paper may be applied to acceleration analysis of other types of spatial mechanisms and that it may serve as an alternative to the well-known vector method.
The Effect of Structural Damping on the Forced Vibrations of Cylindrical Sandwich Shells
Authors: Jones I. W. , Salerno V. L.
Published: December 2011

This paper presents an examination of the effects of structural damping on the axisymmetric vibrations of a cylindrical sandwich shell. It is shown that the use of core materials with high damping properties can result in large reductions in resonant response over conventional materials. The radial vibration of the shell resulting from a time harmonic radial load is first calculated by an exact method. The radial vibration is then calculated by an approximate formula, which requires only a knowledge of the damping properties and the natural (undamped) modes. In numerical examples the resonant vibrations of two steel-faced cylinders are compared. One has a polymeric, the other an elastomeric core. The results indicate that for the assumed conditions they are both effective for suppressing resonant vibration, the polymeric core being generally more effective than the elastomeric core.
Impact on the Surface of a Compressible Fluid
Authors: Skalak R. , Feit D.
Published: December 2011

The pressure field generated by the impact of a rigid or flexible body on the surface of an inviscid, compressible fluid is considered. Some general results for the forces generated by the impact are given. Pressure distributions for rigid wedges are computed from known analogous solutions of linearized supersonic airfoil theory. In the impact problem, the transition from compressible to incompressible behavior is demonstrated as the velocity of impact is reduced.
Estimation of Dynamic Forces in Very High-Speed Impact Forging
Authors: Hillier M. J.
Published: December 2011

A study is made of three methods of estimating die loads in impact forging: By approximate solution of the equations of equilibrium; by an energy method, assuming plane sections remain plane; and using the energy method in association with a kinematically admissible velocity field. Results are given for die pressures and die loads for axisymmetric and plane-strain forging of disks and slabs with smooth dies, perfectly rough dies, and for the case of Coulomb friction.
On the Ductile Behavior of Nominally Brittle Materials During Erosive Cutting
Authors: Sheldon G. L. , Finnie I.
Published: December 2011

It is known that nominally brittle materials may exhibit plastic deformation in indentation, scratching, and microcutting when the loaded region is sufficiently small. The present investigation is concerned with the erosive cutting of nominally brittle materials by the impact of a stream of solid particles and it is shown that ductile behavior should be observed when the particle size and velocity are within certain limits. Experiments on a number of nominally brittle materials confirm this prediction; the ductile behavior being inferred from both the rippled appearance of the eroded surface and the variation of volume removal with angle of impingement.
An Empirical Equation for the Strain-Rate Effect on Roll Separating Force in Cold Rolling
Authors: Inhaber H.
Published: December 2011

While decreases in roll separating force with increasing speeds in cold rolling have been noted in many instances, their recording has been primarily qualitative. In order to proceed eventually to a firm understanding of this phenomenon, quantitative analyses are needed. Work is presented here on the formulation of an empirical equation describing the strain-rate phenomenon. As noted previously, the effect varies with reduction, and its rate of change diminishes as large strip speeds are approached. The derived equation is correlated with other experimental work and, in general, good agreement is reached.
Maximum Profit as the Criterion in the Determination of the Optimum Cutting Conditions
Authors: Wu S. M. , Ermer D. S.
Published: December 2011

Maximum profit is an appropriate criterion for the selection of the optimum machining conditions rather than the conventional criteria of minimum cost or maximum production rate. A simple example is presented to illustrate the determination of the maximum-profit cutting speed by application of a fundamental economic principle that maximum profit occurs at the production rate where the marginal revenue equals the marginal cost. The effects of the demand function, feed, and cost and time parameters on the determination of the maximum-profit cutting speed are analyzed. Emphasis is given to the investigation of a range of optimum cutting speeds, instead of the theoretical optimum speed, for practical applications.
The Effect of Anisotropy and Work-Hardening Characteristics on the Stress and Strain Distribution in Deep Drawing
Authors: Chiang D. C. , Kobayashi Shiro
Published: December 2011

In the process of the deep drawing of a cup, anisotropy and work-hardening characteristics of the material were introduced, by use of the incremental strain theory, into the calculation of stress and strain distributions and the punch force, and the effect of these characteristics on the limiting drawing ratio was obtained. Calculations were carried out by using the FORTRAN language on an IBM 7094 computer at the University of California.
Electrochemical Machining—Prediction and Correlation of Process Variables
Authors: Hopenfeld J. , Cole R. R.
Published: December 2011

The relationship between total current, applied potential, electrolyte flow rate, electrolyte conductivity, and electrode gap in electrochemical machining was investigated experimentally and analytically. An electrolytic cell was designed permitting the electrode gap to be observed and photographed. A 0.25 × 0.375-in. rectangular 1100F aluminum anode was used. Electrode gap varied between 0.013 and 0.033 in. The electrolyte was potassium chloride in concentrations from 0.67 normal to 1.7 normal. Current density range was 40–450 amp/in. and electrolyte flow rate was 0.22 to 0.98 gal/min. The photographs taken of the electrode gap during operation clearly show development of a hydrogen bubble layer next to the cathode. Based upon a mathematical model incorporating the bubble layer, an equation in a nondimensional form has been derived describing the functional relationship between process variables. This equation correlates the experimental data within plus or minus 15 percent. An equation which predicts the local current distribution, and hence anode dissolution rate, along the electrode gap in the direction of electrolyte flow is also presented. Based on the theoretical analysis, optimum operation in electrochemical machining from the standpoint of uniformity of metal removal is discussed.
Flow Boiling Characteristics for R1234ze(E) in 1.0 and 2.2 mm Circular Channels
Authors: Bigonha Tibiriçá Cristiano , Ribatski Gherhardt , Richard Thome John
Published: December 2011

Experimental flow boiling heat transfer results are presented for horizontal 1.0 and 2.2 mm I.D. (internal diameter) stainless steel tubes for tests with R1234ze(E), a new refrigerant developed as a substitute for R134a with a much lower global warming potential (GWP). The experiments were performed for these two tube diameters in order to investigate a possible transition between macro and microscale flow boiling behavior. The experimental campaign includes mass velocities ranging from 50 to 1500 kg/m2 s, heat fluxes from 10 to 300 kW/m2, exit saturation temperatures of 25, 31 and 35 °C, vapor qualities from 0.05 to 0.99 and heated lengths of 180 mm and 361 mm. Flow pattern characterization was performed using high speed videos. Heat transfer coefficient, critical heat flux and flow pattern data were obtained. R1234ze(E) demonstrated similar thermal performance to R134a data when running at similar conditions.
Heat Transfer to Suspensions of Microencapsulated Phase Change Material Flowing Through Minichannels
Authors: Dammel Frank , Stephan Peter
Published: December 2011

The heat transfer to water-based suspensions of microencapsulated phase change material (MEPCM) flowing laminarly through rectangular copper minichannels was investigated both experimentally and numerically. The MEPCM-particles had an average size of 5 μm and contained as phase change material n-eicosane, which has a theoretical melting temperature of 36.4 °C. Water and suspensions with particle mass fractions of 10% and 20% were considered. While the experiments result in rather global values such as wall temperatures at certain points, suspension in- and outlet temperatures, and the pressure drop, the numerical simulations allow additionally a more detailed insight, for example, into the temperature distribution in the flowing suspension. The results show that MEPCM suspensions are only advantageous in comparison to water in a certain range of parameter combinations, where the latent heat is exploited to a high degree. The available latent heat storage potential, which depends on the particle fraction in the suspension and on the mass flow rate, has to be in the same order of magnitude as the supplied heat. Moreover, the mean residence time of the particles in the cooling channels must not be considerably shorter than the characteristic time for heat conduction perpendicular to the flow direction. Otherwise, the particles in the center region of the flow leave the cooling channels with still solid cores, and their latent heat is not exploited. Furthermore, the benefit of the added MEPCM particles depends on the inlet temperature, which has to be slightly below the theoretical melting temperature, and on the subcooling temperature after the heat supply, which has to be sufficiently low to guarantee that the entire phase change material solidifies again before it re-enters the cooling channels. The suspensions showed Newtonian behavior in the viscosity measurement. The actual pressure drop determined in the experiments is smaller than the pressure drop estimation based on the measured viscosities. The difference between the two values increases with increasing particle mass fraction. This shows that the particles are not evenly distributed in the flowing suspension, but that there is a particle-depleted layer close to the channel walls. This reduces the required pumping power, but makes it even more important to provide conditions, in which a sufficiently large amount of the supplied heat is conducted to the center region of the channels.
Gas Microflows in the Slip Flow Regime: A Critical Review on Convective Heat Transfer
Authors: Colin Stéphane
Published: December 2011

Accurate modeling of gas microvection is crucial for a lot of MEMS applications (microheat exchangers, pressure gauges, fluidic microactuators for active control of aerodynamic flows, mass flow and temperature microsensors, micropumps, and microsystems for mixing or separation for local gas analysis, mass spectrometers, vacuum, and dosing valves…). Gas flows in microsystems are often in the slip flow regime, characterized by a moderate rarefaction with a Knudsen number of the order of 10−2–10−1. In this regime, velocity slip and temperature jump at the walls play a major role in heat transfer. This paper presents a state of the art review on convective heat transfer in microchannels, focusing on rarefaction effects in the slip flow regime. Analytical and numerical models are compared for various microchannel geometries and heat transfer conditions (constant heat flux or constant wall temperature). The validity of simplifying assumptions is detailed and the role played by the kind of velocity slip and temperature jump boundary conditions is shown. The influence of specific effects, such as viscous dissipation, axial conduction and variable fluid properties is also discussed.
Vapor Delivery Systems for the Study of the Effects of Reformate Gas Impurities in HT-PEM Fuel Cells
Authors: Araya Samuel S. , Kær Søren K. , Andreasen Søren J.
Published: December 2011

The reforming of methanol can be an alternative source of hydrogen for fuel cells because it has many practical advantages over hydrogen, mainly due to the technological limitations related to the storage, supply, and distribution of the latter. However, despite the ease of methanol handling, impurities in the reformate gas produced from methanol steam reforming can affect the performance and durability of fuel cells. In this paper different vapor delivery systems, intended to assist in the study of the effects of some of the impurities, are described and compared with each other. A system based on a pump and electrically heated evaporator was found to be more suitable for the typical flow rates involved in the anode feed of an H3PO4/PBI based HT-PEMFC unit cell assembly. Test stations composed of vapor delivery systems and mass flow controllers for testing the effects of methanol slip, water vapor, CO, and CO2 are also illustrated.
Investigation of 6Li Enriched Particle Dispersion in Fluorescent Electrospun Polymer Nanofibers to be Used as Thermal Neutron Scintillators
Authors: Young Stephen A. , Sen Indraneel , Penumadu Dayakar
Published: December 2011

Electrospun polymer nanofibers are attractive due to their unique volume-to-surface area, chemical, electrical, and optical properties. Department of Homeland security has interest in applications with polymeric scintillation detectors that directly discriminate between neutron and gamma radiations using manufacturing techniques that are inexpensive and which can be effectively implemented to produce large area detectors. Lithium-6 (6Li) isotope has a significant thermal neutron cross-section and produces high energy charged particles upon thermal neutron absorption. In this research, 6Li loaded polymer composite was successfully spun onto a stationary stainless steel target creating a thermal neutron scintillator made of randomly oriented fibers. Fiber mats thus obtained were characterized using scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS) for morphology, and fluorospectroscopy for optical properties. Additionally, the fiber mats were characterized for polymeric properties including microstructure evaluation and response to thermal neutrons, alpha, beta, and gamma radiation using suitable radiation facilities. Fiber matrix was made out of an aryl vinyl polymer and a wavelength shifting fluor with efficient resonant energy transfer characteristics. The mats produced had scintillation fibers having diameters from 200 nm to 3.2 μm.
APPLICATION OF DAMAGE MODEL WITH MATERIAL FLOW EVALUATION TO HIGH TEMPERATURE COMPRESSION PROCESSES
Authors: JEONG CHANSEO , YANAGIMOTO JUN
Published: December 2011

Mechanisms of ductile failure in a compression process are studied, based on micro-structural considerations, with analytical and experimental investigations performed on a cylindrical specimen. Geometrical softening is able to occur by void if the shear band is generated inside of materials. The original Gurson model is used to analyze tensile deformation, and a modified Gurson model is proposed, which incorporates damage accumulation under shear and compression. This modified Gurson model is also applied to the void closure of sintered material under compression loading. However, the compressed materials must be considered in both the void nucleation and closure, because the void is nucleated and closed at a specific angle. The results of individual analyses of nucleation and closure do not agree with observations, but the analysis considered here, of both the nucleation and closure of a void, corresponds well with experimental results.
THE ROLE OF PARTICLES ANNEALING TEMPERATURE ON MAGNETORHEOLOGICAL EFFECT
Authors: SEDLACIK M. , PAVLINEK V. , SAHA P. , SVRCINOVA P. , FILIP P.
Published: December 2011

The spinel nanocrystalline cobalt ferrite ( CoFe 2 O 4) particles were prepared via a sol–gel method followed by the annealing process. Their structural, magnetic and magnetorheological (MR) properties depending upon the annealing temperature were investigated. The X-ray diffraction analysis revealed that the higher annealing temperature, the larger grain size of CoFe 2 O 4 particles resulting in larger magnetic domains in particles. The saturation magnetization, determined via a vibrating sample magnetometry, increased with annealing temperature and, in contrast, the coercivity decreased. The rheological behavior of CoFe 2 O 4 particles based MR suspensions determined under the small-strain oscillatory shear flow in magnetic field showed that higher annealing temperature reflects in larger changes of rheological properties.
GROUND STATES OF ONE-DIMENSIONAL LONG-RANGE FERROMAGNETIC ISING MODEL WITH EXTERNAL FIELD
Authors: KERIMOV AZER
Published: December 2011

A zero-temperature phase-diagram of the one-dimensional ferromagnetic Ising model is investigated. It is shown that at zero temperature spins of any compact collection of lattice points with identically oriented external field are identically oriented.
THE EFFECT OF CARBON NANOTUBE CHIRALITY ON THE PERFORMANCE OF THE STRAINED TUNNELING CARBON NANOTUBE FETs
Authors: YOUSEFI REZA
Published: December 2011

In this paper, using the non-equilibrium Green's function formalism (NEGF), the effect of the chirality of carbon nanotube (CNT) on the performance of the strained tunneling carbon nanotube field effect transistors (T-CNTFETs) has been investigated. In this work, all evaluations are done by this assumption that the ON current, I ON , is the main performance metric in the T-CNTFETs. The uniaxial strain has been considered in this work. On the other hand, for constructing a transistor with a desired I ON , a variety of CNTs with the appropriate uniaxial strain could be used. The results of doing some comparisons among these situations show that, the use of the small diameter CNTs with the appropriate uniaxial strain could lead to the transistors with the better switching behavior. Likewise, the use of the large diameter CNTs with the appropriate uniaxial strain could result to the transistors with a higher I ON /I OFF ratio.
Adjuvant Therapy: Melanoma
Authors: Davar Diwakar , Tarhini Ahmad , Kirkwood John M.
Published: December 2011

With an incidence that is increasing at 2–5% per year, cutaneous melanoma is an international scourge that disproportionately targets young individuals. Despite much research, the treatment of advanced disease is still quite challenging. Immunotherapy with high-dose interferon-α2b or interleukin-2 benefits a select group of patients in the adjuvant and metastatic settings, respectively, with significant attendant toxicity. Advances in the biology of malignant melanoma and the role of immunomodulatory therapy have produced advances that have stunned the field. In this paper, we review the data for the use of interferon-α2b in various dosing ranges, vaccine therapy, and the role of radiotherapy in the adjuvant setting for malignant melanoma. Recent trials in the metastatic setting using anticytoxic T-lymphocyte antigen-4 (anti-CTLA-4) monoclonal antibody therapy and BRAF inhibitor therapy have demonstrated clear benefit with prolongation of survival. Trials investigating combinations of these novel agents with existing immunomodulators are at present underway.
Analysis of Linearly Elastic Inextensible Frames Undergoing Large Displacement and Rotation
Authors: Rungamornrat Jaroon , Tangnovarad Peerasak
Published: December 2011

This paper presents an efficient semi‐analytical technique for modeling two‐dimensional, linearly elastic, inextensible frames undergoing large displacement and rotation. A system of ordinary differential equations governing an element is first converted into a system of nonlinear algebraic equations via appropriate enforcement of boundary conditions. Taylor′s series expansion is then employed along with the co‐rotational approach to derive the best linear approximation of such system and the corresponding exact element tangent stiffness matrix. A standard assembly procedure is applied, next, to obtain the best linear approximation of governing nonlinear equations for the structure. This final system is exploited in the solution search by Newton‐Ralphson iteration. Key features of the proposed technique include that (i) exact load residuals are evaluated from governing nonlinear algebraic equations, (ii) an exact form of the tangent stiffness matrix is utilized, and (iii) all elements are treated in a systematic way via direct stiffness strategy. The first two features enhance the performance of the technique to yield results comparable to analytical solutions and independent of mesh refinement whereas the last feature allows structures of general geometries and loading conditions be modeled in a straightforward fashion. The implemented algorithm is tested for various structures not only to verify its underlying formulation but also to demonstrate its capability and robustness.
Real‐Time Fixed‐Order Lateral H2 Controller for Micro Air Vehicle
Authors: M. Meenakshi , Bhat M. Seetharama
Published: December 2011

This paper presents the design and development of a fixed low‐order, robust H2 controller for a micro air vehicle (MAV) named Sarika‐2. The controller synthesis uses strengthened discrete optimal projection equations and frequency‐dependent performance index to achieve robust performance and stability. A single fixed gain low‐order dynamic controller provides simultaneous stabilization, disturbance rejection, and sensor noise attenuation over the entire flight speed range of 16 m/sec to 26 m/sec. Comparative study indicates that the low‐order H2‐controller achieves robust performance levels similar to that of full order controller. Subsequently, the controller is implemented on a digital signal processor‐based flight computer and is validated through the real time hardware in loop simulation. The responses obtained with hardware in loop simulation compares well with those obtained from the offline simulation.
Laryngeal Radiation Fibrosis: A Case of Failed Awake Flexible Fibreoptic Intubation
Authors: Huitink Johannes M. , Zijp Lambert
Published: December 2011

Awake fibreoptic intubation is accepted as the gold standard for intubation of patients with an anticipated difficult airway. Radiation fibrosis may cause difficulties during the intubation procedure. We present an unusual severe case of radiation induced changes to the larynx, with limited clinical symptoms, that caused failure of the fibreoptic intubation technique. A review of the known literature on radiation fibrosis and airway management is presented.
Metal-Based Biologically Active Compounds: Synthesis, Spectral, and Antimicrobial Studies of Cobalt, Nickel, Copper, and Zinc Complexes of Triazole-Derived Schiff Bases
Authors: Singh Kiran , Kumar Yogender , Puri Parvesh , Sharma Chetan , Aneja Kamal Rai
Published: December 2011

A series of cobalt, nickel, copper, and zinc complexes of bidentate Schiff bases derived from the condensation reaction of 4-amino-5-mercapto-3-methyl/ethyl-1,2,4-triazole with 2,4-dichlorobenzaldehyde were synthesized and tested as antimicrobial agents. The synthesized Schiff bases and their metal complexes were characterized with the aid of elemental analyses, magnetic moment measurements, spectroscopic and thermogravimetric techniques. The presence of coordinated water in metal complexes was supported by infrared and thermal gravimetric studies. A square planar geometry was suggested for Cu(II) and octahedral geometry proposed for Co(II), Ni(II), and Zn(II) complexes. The Schiff bases and their metal complexes have been screened for antibacterial (Pseudomonas aeruginosa, Bacillus subtilis) and antifungal activities (Aspergillus niger, A. flavus). The metal complexes exhibited significantly enhanced antibacterial and antifungal activity as compared to their simple Schiff bases.
Performance of Dye-Sensitized Solar Cells with (PVDF-HFP)-KI-EC-PC Electrolyte and Different Dye Materials
Authors: Noor M. M. , Buraidah M. H. , Yusuf S. N. F. , Careem M. A. , Majid S. R. , Arof A. K.
Published: December 2011

A plasticized polymer electrolyte system composed of PVDF-HFP, potassium iodide (KI), and equal weight of ethylene carbonate (EC) and propylene carbonate (PC) has been used in a dye-sensitized solar cell (DSSC). The electrolyte with the composition 40 wt. % PVDF-HFP-10 wt. % KI-50 wt. % (EC + PC) exhibits the highest room temperature ionic conductivity of 1.10 × 10−3 S cm−1. A small amount of iodine crystal of about 10 wt. % of KI was added to the electrolyte in the liquid state to provide the redox couple for DSSC operation. The polymer electrolyte films were prepared by the solvent casting method. The DSSCs were fabricated with the electrolyte film sandwiched between a TiO2/dye photoelectrode and a Pt-counter electrode and characterized under 100 mW cm−2white light. The DSSC performance with different dyes such as Ruthenizer 535 (N3), anthocyanin, chlorophyll, and a mixture of anthocyanin and chlorophyll (v/v=1) has been compared. The DSSC with Ruthenizer 535 (N3) dye exhibits the best performance with a short-circuit current density of 8.16 mA cm−2, open-circuit voltage of 0.76 V, fill factor of 0.35, and photoconversion efficiency of 2.2%.
Insomnia Symptoms and Cardiovascular Disease among Older American Indians: The Native Elder Care Study
Authors: Sabanayagam Charumathi , Shankar Anoop , Buchwald Dedra , Goins R. Turner
Published: December 2011

Background. Cardiovascular disease (CVD) is the leading cause of death among American Indians. It is not known if symptoms of insomnia are associated with CVD in this population.Methods. We examined 449 American Indians aged ≥55 years from the Native Elder Care Study. The main outcome-of-interest was self-reported CVD.Results. Short sleep duration, daytime sleepiness, and difficulty falling asleep were positively associated with CVD after adjusting for demographic, lifestyle, and clinical risk factors. Compared with a sleep duration of 7 h, the multivariable odds ratio (OR) (95% confidence interval [CI]) of CVD among those with sleep duration ≤5 h was 2.89 (1.17–7.16). Similarly, the multivariable OR (95% CI) of CVD was 4.45 (1.85–10.72) and 2.60 (1.25–5.42) for daytime sleepiness >2 h and difficulty falling asleep often/always.Conclusion. Symptoms of insomnia including short sleep duration, daytime sleepiness, and difficulty falling asleep are independently associated with CVD in American Indians aged ≥55 years.
Chinese Medicine’s Intervention Effect on Nogo-A/NgR
Authors: Qin Xiu-de , Kang Li-yuan , Liu Yu , Huang Yan , Wang Shuo , Zhu Jin-qiang
Published: December 2011

Cerebral vascular disease is very common in the elderly and is one of the most dangerous diseases which is hazardous to the body’s health, and it is the medical specialists’ study hot spot not only in the clinical field but also in the medical basic research field. Neural regeneration has been paid more and more attention in recent years. Nogo’s function in the process of neural regeneration has become the focal point since it was discovered in the year 2000. Many studies elucidate that Nogo negatively affects the neural regeneration and plasticity. Chinese medicine plays an important role in the prevention and treatment of neural diseases, and recently some researches about the Chinese medicine’s intervention effect on Nogo-A/NgR sprang up, so it is necessary to make a review on this aspect.
Redox Regulation of Nonmuscle Myosin Heavy Chain during Integrin Engagement
Authors: Fiaschi Tania , Cozzi Giacomo , Chiarugi Paola
Published: December 2011

On the basis of our findings reporting that cell adhesion induces the generation of reactive oxygen species (ROS) after integrin engagement, we were interested in identifying redox-regulated proteins during this process. Mass spectrometry analysis led us to identify nonmuscle myosin heavy chain (nmMHC) as a target of ROS. Our results show that, while nmMHC is reduced in detached/rounded cells, it turns towards an oxidized state in adherent/spread cells due to the integrin-engaged ROS machinery. The functional role of nmMHC redox regulation is suggested by the redox sensitivity of its association with actin, suggesting a role of nmMHC oxidation in cytoskeleton movement. Analysis of muscle MHC (mMHC) redox state during muscle differentiation, a process linked to a great and stable decrease of ROS content, shows that the protein does not undergo a redox control. Hence, we propose that the redox regulation of MHC in nonprofessional muscle cells is mandatory for actin binding during dynamic cytoskeleton rearrangement, but it is dispensable for static and highly organized cytoskeletal contractile architecture in differentiating myotubes.
Microstrip Patch Antenna Bandwidth Enhancement Using AMC/EBG Structures
Authors: Hadarig R. C. , de Cos M. E. , Las-Heras F.
Published: December 2011

A microstrip patch antenna with bandwidth enhancement by means of artificial magnetic conductor (AMC)/electromagnetic band-gap structure (EGB) is presented. The electrical characteristics of the embedded structure are evaluated using MoM simulations. The manufactured prototypes are characterized in terms of return loss, gain, and radiation pattern measurements in an anechoic chamber.
Characteristics and Photocatalytic Properties of Thin Film Prepared by Sputter Deposition and Post-N+Ion Implantation
Authors: Shukur Haider A. , Sato Mitsunobu , Nakamura Isao , Takano Ichiro
Published: December 2011

TiO2thin films of a rutile, an anatase, and a mixture type with anatase and rutile were fabricated by a magnetron sputtering method. The fabricated films were irradiated by N+ions with several doses using the Freeman ion source. Atomic force microscopy (AFM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and UV-VIS spectrophotometer were employed to investigate morphology, structure, chemical state, and optical characteristics, respectively. Photocatalytic activity was evaluated by degradation of a methylene blue solution using UV and visible light. TiO2thin films with each structure irradiated by N+ions showed the different N concentration in the same N+ion dose and the chemical state of XPS results suggested that an O atom in TiO2lattice replaced by an N atom. Therefore the photocatalytic activity of TiO2thin films was improved under visible light. The maximum photocatalytic activity of TiO2thin films with each structure was indicated at N concentration of 2.1% for a rutile type, of 1.0% for an anatase type, and of 3.8% for a mixture type under the condition of  ions/cm2in N+ion dose.
Differential Role of BCL2 in Molecular Subtypes of Diffuse Large B-cell Lymphoma
Authors: Dunleavy Kieron , Wilson Wyndham H.
Published: December 2011

Gene expression profiling has been used to divide diffuse large B-cell lymphoma into distinct molecular subtypes with different outcomes following immunochemotherapy. Recently, researchers have shown much interest in investigating the role of biomarkers, such as BCL2, in predicting outcome in diffuse large B-cell lymphoma, particularly in the context of these molecular subtypes. Clin Cancer Res; 17(24); 7505–7. ©2011 AACR.
Prevalence of Apolipoprotein E4 Genotype and Homozygotes (APOE e4/4) among Patients Diagnosed with Alzheimer’s Disease: A Systematic Review and Meta-Analysis
Authors: Ward Alex , Crean Sheila , Mercaldi Catherine J. , Collins Jenna M. , Boyd Dylan , Cook Michael N. , Arrighi H. Michael
Published: December 2011

Background: Population allele frequencies of apolipoprotein E (APOE) vary by geographic region. The purpose of this study is to summarize and evaluate published estimates for the prevalence of APOE e4 carrier status among the population diagnosed with Alzheimer’s disease (AD) by geographic region and country. Methods: A systematic review of English-language publications from January 1, 1985, through May 31, 2010, was conducted. Studies reporting APOE e4 status for patients diagnosed with AD were included in the analysis; trials and autopsies were excluded. APOE e4 data were pooled, and prevalence and 95% confidence intervals (CIs) were calculated. Results: Pooled estimates for APOE e4 carrier prevalence data were derived from 142 independent samples: 48.7% (95% CI: 46.5–51.0), and from 73 samples for e4/4 (homozygotes): 9.6% (95% CI: 8.4–10.8). The highest estimates were in Northern Europe: 61.3% (95% CI: 55.9–66.7), e4/4 prevalence: 14.1% (95% CI: 12.2–16.0). The lowest estimates were in Asia and Southern Europe. Substantial heterogeneity of these prevalence estimates was observed. Conclusions: APOE e4 genotype prevalence varies among AD patients by region and within each country. Further exploration is warranted to better understand the substantial heterogeneity of these prevalence estimates.
The Spectrum Captured: A Methodological Approach to Studying Incidence and Outcomes of Traumatic Brain Injury on a Population Level
Authors: Theadom A. , Barker-Collo S. , Feigin V.L. , Starkey N.J. , Jones K. , Jones A. , Ameratunga S. , Barber P.A. ,   on behalf of the BIONIC Research Group
Published: December 2011

Objective: Drawing on the experience of conducting the Brain Injury Incidence and Outcomes New Zealand in the Community study, this article aims to identify the issues arising from the implementation of proposed guidelines for population-based studies of incidence and outcomes in traumatic brain injury (TBI). Study Design and Setting: All new cases of TBI (all ages and severities) were ascertained over a 1-year period, using overlapping prospective and retrospective sources of case ascertainment in New Zealand. All eligible TBI cases were invited to participate in a comprehensive assessment at baseline and at 1-month follow-up. Results: Our experience to date has revealed the feasibility of case ascertainment methods. Consultation with community health services and professionals resulted in feasible referral pathways to support the identification of TBI cases. ‘Hot pursuit’ methods of recruitment were essential to ensure complete case ascertainment for this population with few additional cases of TBI identified through cross-checks. Conclusion: This review of proposed guidelines in relation to practical study methodology provides a framework for future comparable population-based epidemiological studies of TBI incidence and outcomes in developed countries.
Circulation's
Diabetes Mellitus Studies
Authors:   The Editors
Published: December 2011

The following articles are being highlighted as part of
Circulation'
s Topic Review series. This series will summarize the most important manuscripts, as selected by the editors, published in
Circulation
and the
Circulation
subspecialty journals. The studies included in this article represent the articles related to diabetes mellitus that were published in
Circulation
in 2009 and 2010.
First Impressions From Faces Among U.S. and Culturally Isolated Tsimane’ People in the Bolivian Rainforest
Authors: Zebrowitz Leslie A. , Wang Ruoxue , Bronstad P. Matthew , Eisenberg Dan , Undurraga Eduardo , Reyes-García Victoria , Godoy Ricardo
Published: December 2011

The authors examined the generalizability of first impressions from faces previously documented in industrialized cultures to the Tsimane’ people in the remote Bolivian rainforest. Tsimane’ as well as U.S. judges showed within-culture agreement in impressions of attractiveness, babyfaceness, and traits (healthy, intelligent/knowledgeable, dominant/respected, and sociable/warm) of own-culture faces. Both groups also showed within-culture agreement for impressions of other-culture faces, although it was weaker than for own-culture faces, particularly among Tsimane’ judges. Moreover, there was between-culture agreement, particularly for Tsimane’ faces. Use of facial attractiveness to judge traits contributed to agreement within and between cultures but did not fully explain it. Furthermore, Tsimane’, like U.S., judges showed a strong attractiveness halo in impressions of faces from both cultures as well as the babyface stereotype, albeit more weakly. In addition to cross-cultural similarities in trait impressions from faces, supporting a universal mechanism, some effects were moderated by perceiver and face culture, consistent with perceiver attunements conditioned by culturally specific perceptual learning.
Discipline and Change: How Technologies and Organizational Routines Interact in New Practice Creation
Authors: Labatut Julie , Aggeri Franck , Girard Nathalie
Published: December 2011

In this paper we study the development and implementation of a technology over a long period of time, with a particular focus on how its disciplinary effects interplay with and change organizational routines and actors’ capacities, thus producing new patterns of action. To identify these processes of change and emergence of practices, we propose a combinative theoretical analysis at the interface between institutional and practice-based approaches. Drawing on a rich ethnographic case study, we show how the fact of considering technologies as the combination of three dimensions (technical substrate, managerial philosophy and organizational model) furthers our understanding of institutional change and the creation of new practices. In particular, we examine the internal dynamics between the three dimensions of these technologies and the duality of organizational routines (their ostensive and performative aspects). This enables us to reintroduce practices and agency analysis into an institutional approach to technological change, and to put social history, designers’ assumptions and disciplinary effects of technologies back into the analysis of the micro-dynamics of routine changes. We identify several factors which partially explain divergent technological trajectories concerning institutionalization and emerging structures in two different settings.
Using Organization Structure to Buffer Political Ties in Emerging Markets: A Case Study
Authors: Dieleman Marleen , Boddewyn Jean J.
Published: December 2011

We use and extend resource-dependence theory by analyzing how loosely-coupled organizational structures facilitate the management of political ties by business groups in emerging economies. This topic is particularly salient because business groups are a prevalent organizational form in these countries where they face both a high dependence on governments to secure key resources and a unique set of risks associated with political ties. We identify and analyze four buffering mechanisms that enable loosely-coupled business groups to protect themselves against the adverse effects of such ties. We ground and contextualize these mechanisms by relying on a longitudinal case study of the Salim Group – a very large and well-connected Indonesian business group under the Suharto regime. This study is particularly relevant in the context of the renewed interest in the study of firms’ organizational structure.
Ankle Stabilizers Affect Agility but Not Vertical Jump or Dynamic Balance Performance
Authors: Ambegaonkar Jatin P. , Redmond Charles J. , Winter Christa , Cortes Nelson , Ambegaonkar Shruti J. , Thompson Brian , Guyer Susan M.
Published: December 2011

Ankle stabilizers can reduce ankle sprain incidence and severity by limiting range of motion. Still whether using them affects performance remains unclear. The authors compared effects of 3 ankle stabilizers, tape, lace-up (Swede-O Ankle Lok), and semirigid (Air-Cast Air-Stirrup) braces, and a nonsupport control on vertical jump (Sargent Jump Test), agility (Right-Boomerang Run test), and dynamic balance (Modified Bass Test) in 10 volunteers (4 males, 6 females; 25.6 ± 2.8 years, 167.8 ± 13.7 cm, 61.4 ± 10.7 kg) using repeated-measures ANOVAs. Participants had similar vertical jump ( P = .27; control = 41.40 ± 11.89 cm, tape = 37.90 ± 7.92 cm, Swede-O = 41.40 ± 11.89 cm, Air-Cast = 39.29 ± 10.85 cm) and dynamic balance ( P = .08; control = 92.50 ± 2.46, tape = 91.55 ± 3.53, Swede-O = 97.00 ± 5.32, Air-Cast = 89.40 ± 6.08) but differing agility scores ( P = .03; control = 13.55 ± 1.35 seconds, tape = 14.03 ± 1.5 seconds, Swede-O = 14.10 ± 1.36 seconds, Air-Cast = 14.14 ± 1.41 seconds). Post hoc tests revealed a significant difference ( P = .03) between control and Air-Cast but not between Swede-O ( P = .06) or tape ( P = .07). Effect size ( d) analyses indicated that compared with control, all stabilizers trended to increase agility run times (tape, d = 0.33; Swede-O, d = 0.40; Air-Cast, d = 0.43). Since participants primarily required sagittal plane motion when jumping vertically and had relatively slow directional changes in the dynamic balance test, wearing ankle stabilizers did not hamper jump or balance. However, ankle stabilizers hindered participants’ ability to perform quick directional changes required in the agility test, with the most rigid stabilizer (Air-Cast) affecting agility the most. Clinicians should be aware that ankle stabilizers may affect some performance measures (agility) but not others (jumping, balance) and continue examinations in larger cohorts.

Level of Evidence: Therapeutic, Level II
A Career in Classical Archaeology: An Interview with Marianne Kleibrink
Authors: van Leusen Martijn
Published: December 2011

This interview covers life and work of Marianne Kleibrink, retired Professor of Classical and Mediterranean Archaeology at the Groningen Institute of Archaeology. For more than 25 years she conducted and published excavations at Timpone della Motta near Francavilla Marittima (northern Calabria) and at Satricum (south Lazio), documenting the indigenous roots of these proto-urban sites as well as the transformations they underwent when they became incorporated, respectively, in the colonial Greek and Roman spheres. Her experience as, first, a woman making an academic career for herself in Dutch universities, and, later, as a foreign archaeologist running long-term projects in Italy, echos those of many others.
Two-dimensional difference gel electrophoresis (DIGE) analysis of sera from visceral leishmaniasis patients
Authors: Rukmangadachar Lokesh A , Kataria Jitender , Hariprasad Gururao , Samantaray Jyotish C , Srinivasan Alagiri
Published: December 2011

Introduction

Visceral leishmaniasis is a parasitic infection caused by Lesihmania donovani complex and transmitted by the bite of the phlebotomine sand fly. It is an endemic disease in many developing countries with more than 90% of the cases occurring in Bangladesh, India, Nepal, Sudan, Ethiopia and Brazil. The disease is fatal if untreated. The disease is conventionally diagnosed by demonstrating the intracellular parasite in bone marrow or splenic aspirates. This study was carried out to discover differentially expressed proteins which could be potential biomarkers.

Methods

Sera from six visceral leishmaniasis patients and six healthy controls were depleted of high abundant proteins by immunodepletion. The depleted sera were compared by 2-D Difference in gel electrophoresis (DIGE). Differentially expressed proteins were identified the by tandem mass spectrometry. Three of the identified proteins were further validated by western blotting.

Results

This is the first report of serum proteomics study using quantitative Difference in gel electrophoresis (DIGE) in visceral leishmaniasis. We identified alpha-1-acidglycoprotein and C1 inhibitor as up regulated and transthyretin, retinol binding protein and apolipoprotein A-I as down regulated proteins in visceral leishmaniasis sera in comparison with healthy controls. Western blot validation of C1 inhibitor, transthyretin and apolipoprotein A-I in a larger cohort (n = 29) confirmed significant difference in the expression levels (p < 0.05).

Conclusions

In conclusion, DIGE based proteomic analysis showed that several proteins are differentially expressed in the sera of visceral leishmaniasis. The five proteins identified here have potential, either independently or in combination, as prognostic biomarkers.