bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of seed addition on beetle assemblages during the re‐creation of species‐rich lowland hay meadows
Authors: WOODCOCK BEN A. , WESTBURY Duncan B. , BROOK Alex J. , LAWSON Clare S. , EDWARDS Andrew R. , HARRIS Stephanie J. , HEARD Matthew S. , BROWN Valerie K. , MORTIMER Simon R.
Published: October 2011

Abstract.  1. Species‐rich lowland hay meadows are of conservation importance for both plants and invertebrates; however, they have declined in area across Europe as a result of conversion to other land uses and management intensification. The re‐creation of these grasslands on ex‐arable land provides a valuable approach to increasing the extent and conservation value of this threatened habitat.

2. Over a 3‐year period a replicated block design was used to test whether introducing seeds promoted the re‐creation of both plant and phytophagous beetle assemblages typical of a target hay meadow. Seeds were harvested from local hay meadows, and applied to experimental plots in the form of either green hay or brush harvesting seeds.

3. Green hay spreading achieved the greatest success in re‐creating plant and phytophagous beetle assemblages. While re‐creation success increased over time for both taxa, for the phytophagous beetles the greatest increase in re‐creation success relative to the establishment year also occurred where green hay was applied. We also considered the phytophagous beetles in terms of functional traits that describe host plant specificity, larval feeding location and dispersal. Phytophagous beetle functional trait composition was most similar to the target hay meadow assemblage where some form of seed addition was used, i.e. hay spreading or brush harvested seeds.

4. This study identified the importance of introducing target plant species as a mechanism to promote the re‐creation of phytophagous beetle communities. Seed addition methods (e.g. green hay spreading) are crucial to successful hay meadow re‐creation.
Operational Entrepreneurship: How Operations Management Research Can Advance Entrepreneurship
Authors: Shepherd Dean A. , Patzelt Holger
Published: October 2011

In this article, we introduce the notion of operational entrepreneurship—the selection and management of transformation processes for recognizing, evaluating, and exploiting opportunities for potential value creation—to offer examples of research opportunities at the interface of entrepreneurship and operations management. Specifically, we believe that operations management has been under‐utilized for gaining a deeper understanding of (i) the knowledge and motivation required for opportunity recognition, (ii) evaluations of a recognized opportunity to determine if it represents an opportunity for the specific entrepreneur, and (iii) the role that feedback from an exploitation of a current opportunity plays in the recognition and evaluation of subsequent opportunities. We also introduce (but not develop) the notion of entrepreneurial operations.
Finite Deflections of an Elastic Circular Plate With a Central Hole
Authors: Koenig H. A. , Llorens R. E. , Chou P. C.
Published: October 2011

The von Karman equations for large deflections of an elastic circular plate containing a central hole and subjected to a concentrated ring load are presented in dimensionless and finite-difference form. Because of the nonlinear character of these equations an iterative technique must be employed to obtain a solution of the system of finite-difference equations and their corresponding boundary conditions. An analytical representation of the bounds within which the solution must lie is derived using a Green’s function approach. Finally, an example is solved numerically and the results discussed.
Contact Stress Between Two-Dimensional Finite Elastic Bodies
Authors: Blackketter D. O. , Christensen H. D.
Published: October 2011

A method is presented for determining the contact stress distribution between two two-dimensional finite elastic bodies with general surface configurations. The bodies treated are nearly rectangular with surfaces which deviate from the rectangular shape by a small amount. The approximate method used involves a solution to the partial differential equations of elasticity for surface load expressed in terms of a trigonometric series. The coefficients of the trigonometric series are evaluated by enforcement of the appropriate constraint conditions. Experimental and theoretical stress distributions are compared and are in good agreement.
The Application of Continued Fractions to Wave Propagation in a Semi-Infinite Elastic Cylindrical Membrane
Authors: Akin J. E. , Counts J.
Published: October 2011

The Laplace transform of the axial stress resultant in an impacting semi-infinite elastic cylindrical membrane is generated in the form of an exponential function involving the wave speed, and a series in powers of the reciprocal of the transform parameter. Continued fractions are used to obtain rational approximations for the transform represented by the series. The rational approximations, which are in the form of the ratio of two polynomials, are inverted by standard techniques. Results are presented for the axial stress resultant for small and large values of time and are compared with previously published results.
Numerical Solutions of Transients in Pneumatic Networks: Part 2—Nonlinear Termination Problems
Authors: Tsao S.
Published: October 2011

This paper presents an iterative method of solution to the mathematical problems involved in the termination of transmission lines in arbitrary devices. The solutions to two simple, but typical, termination problems are computed and compared with experimental results.
Improved Linearized Velocity Profiles for Turbulent Free Shear Layers
Authors: Lamb J. P. , Greenwood T. F. , Gaddis J. L.
Published: October 2011

The longitudinal motion equation for turbulent boundary layers is linearized in a manner which retains the spirit of Reichardt’s inductive theory. The resulting approximate velocity profiles for isobaric free shear layers are found to be functions of the density field as well as the velocity of the secondary stream. Using the amount of transverse shift, which is required to satisfy the momentum integral equation, as a figure of merit, it is shown that the alternate profiles are generally better representations of the flow field than distributions obtained with the classic Oseen linearization for both developing and fully developed free layers. The alternate velocity distributions, in combination with integral conservation equations, are shown to yield characteristic velocities in the midpart of the profile which are in agreement with those obtained from more elaborate nonlinear analyses.
One-Dimensional Impact Waves in Inhomogeneous Elastic Media
Authors: Reiss Edward L.
Published: October 2011

Several one-dimensional impact problems for inhomogeneous elastic media are reduced by suitable transformations of variables to three different canonical forms. One of them is the impact problem for the wave equation with variable sound speed. Another, which we call Problem I, is the impact problem for the Klein-Gordon equation with variable coefficients. Several methods of approximating the solution of Problem I are discussed. The wave front approximation is obtained by assuming that sufficiently near the discontinuity propagating from the impacted boundary the solution has a Taylor series in time. The coefficients in the series are the time derivatives of the solution evaluated on the discontinuity. They are obtained from an analysis of the propagation of the discontinuity using the theory of weak solutions. A formal asymptotic expansion of the solution is obtained for oscillatory impact data. Reflections from boundaries are also considered. Perturbation methods for media with slowly varying inhomogeneities and asymptotic methods for media with rapidly varying inhomogeneities are briefly discussed.
Forced Vibrations of a Single-Degree-of-Freedom System With Coulomb Bearing Friction
Authors: Wilms E. V.
Published: October 2011

The equation of motion of a single-degree-of-freedom mechanical system with Coulomb friction acting at two bearings is derived. The equation is nonlinear, but may be solved by piecewise linearization. For the case of transient oscillations, the amplitude decreases by a constant ratio every half cycle and, in this respect, the behavior resembles that of viscous damping rather than the type of Coulomb damping which has previously been investigated. The steady-state response with a forcing function is determined for the case of small damping. In addition to the amplitude and phase angle of the motion, a solution requires the determination of a second angle which defines the linearized regions.
End Thermal Stresses in a Long Circular Rod
Authors: Chu W. H. , Dodge F. T.
Published: October 2011

The title problem is solved by the method of collocation utilizing complex nonorthogonal characteristic functions. It is shown that the characteristic values can be obtained by repeated linear interpolation without much difficulty. Ten roots are given for the case of Poisson’s ratio equaling 0.3. For large temperature gradients, an example is given which shows high end stresses. The general solution due to the end effect dies down at the rate of exp (–2.722 z/a) or faster, but its magnitude depends on the steepness of the temperature gradient. This paper also shows that the Saint-Venant principle may not always be sufficient, that the end stress could be critical, and that, therefore, it should be calculated.
Effects of Streamwise Vortices on Laminar Boundary-Layer Flow
Authors: Fannelop T. K.
Published: October 2011

The effects of periodic transverse velocity fluctuations are investigated for boundary-layer flow over a flat plate. The method used is a perturbation expansion of the three-dimensional boundary-layer equations in terms of the small transverse velocity component. The equations are reduced to similarity form by means of suitable transformations. The second-order terms are expressed in terms of the first-order (Blasius) variables and are found to increase linearly with the streamwise coordinate. The present heat-transfer solution agrees with the more qualitative results of Persen. The derived velocity profiles are in exact agreement with the results of Crow’s more elaborate analysis based on the Navier-Stokes equations.
Centrifuge Analysis—Effects on Sedimentation Coefficients of Angular Velocity Lag, of Deviations From Stokes’ Law of Drag, and of Acceleration Effects
Authors: Langford David
Published: October 2011

Sedimentation coefficients are affected by an angular velocity lag which exists between sedimenting particles and the carrier fluid, by known deviations from Stokes’ law of drag, and by particle acceleration. These phenomena may sometimes cause orders of magnitude changes in sedimentation coefficients when the value of the dimensionless parameter wδ2/ν is greater than about 0.01, where w = angular velocity of centrifuge in rad/sec, δ = diameter of sedimenting particle, and ν = kinematic viscosity of carrier fluid. The value of wδ2/ν can easily exceed 0.01 in existing centrifuges. (Sample results are presented graphically for wδ2/ν ≦ 1000 for the case of a particle density equal to twice the density of the carrier fluid.)
On the Final States of Shallow Arches on Elastic Foundations Subjected to Dynamical Loads
Authors: Hsu C. S. , Kuo C. T. , Lee S. S.
Published: October 2011

Given in this paper is a nonlinear analysis of snap-through problems of shallow arches on linear elastic foundations subjected to time-varying loads which have a time-independent character as τ → ∞. Specific problems studied in detail are simply supported sinusoidal arches under impulsive loads, under time-varying loads with asymptotic spatial distributions of sinusoidal shape, and under time-varying loads with uniform asymptotic spatial distributions. It is found that for a very wide range of the foundation modulus a necessary and sufficient condition for stability against snap-through can be established and the final state of the arch predicted. Outside this range and when the loads are timewise step loads, useful sufficient conditions for instability and sufficient conditions for stability can be found separately. The nonlinear treatment presented here is exact in the sense that no approximation is made or is required in the mathematical analysis.
Finite Deflections and Snap-Through of High Circular Arches
Authors: Huddleston J. V.
Published: October 2011

The buckling behavior of two-hinged circular arches with any height-to-span ratio is studied by formulating the problem as a two-point boundary-value problem consisting of six nonlinear, first-order differential equations and appropriate boundry conditions. The theory is exact in the sense that no restrictions are placed on the size of the deflections or on the thickness of the arch. It is approximate in the sense that plane sections are assumed to remain plane, shear deformation is neglected, and the geometric properties of each cross section are assumed to remain constant during the deflection. The problem is solved on a digital computer by a shooting method that uses two levels of regula falsi and one of iteration. Selected results as plotted by the computer are shown and interpreted.
Large Inextensional Deflection of Thin Cantilevered Plates
Authors: Lin T. H. , Lin S. R. , Mazelsky B.
Published: October 2011

The calculation of large bending deflections of thin plates by available techniques are either too difficult to use or are limited to deflections which are below 20 percent of the plate’s length and/or width. The present method predicts, and is substantiated by experiment, the maximum deflections of such thin plates within a few percent wherein the deflections are larger than half the length and/or width of the thin plate.
A Diffraction Problem and Crack Propagation
Authors: Jahanshahi A.
Published: October 2011

The exact solution to the problem of diffraction of plane harmonic polarized shear waves by a half-plane crack extending under antiplane strain is constructed. The solution is employed to study the nature of the stress field associated with an extending crack in an elastic medium excited by stress waves.
Stability of Linear Dynamic Systems With Narrow-Band Parametric Excitation
Authors: Caughey T. K. , Dickerson J. R.
Published: October 2011

A Lyapunov-type approach is used to establish sufficient conditions guaranteeing the asymptotic stability of a class of linear dynamic systems with bounded, narrow-band parametric excitation.
Diffraction of Transient Elastic Waves by a Spherical Cavity
Authors: Norwood F. R. , Miklowitz J.
Published: October 2011

The diffraction of transient elastic waves by a spherical cavity is treated. Two cases are considered: (1) A suddenly applied normal point load, and (2) the impingement of a plane transient dilatational pulse on the cavity. The method used determines the solution only in the shadow zones; that is, those points which cannot be connected to the source of disturbance by straight-line rays. Analytical results are obtained and evaluated for the displacements at the cavity wall.
Rayleigh Problem in Slip Flow With Modified Initial Conditions
Authors: Reddy K. C.
Published: October 2011

The initial conditions of the linearized Rayleigh problem in slip flow are modified so as to satisfy the free molecule flow conditions at the start of the motion. Approximate initial profiles for velocity and temperature are chosen which would yield correct values of velocity slip, temperature jump, and so on, at the start of the motion. The continuum solutions with the modified initial conditions and slip boundary conditions are found to be uniformly valid for all times of motion and agree well with the results of the kinetic theory analyses of the problem.
Application of Kirchhoff’s Integral Equation Formulation to an Elastic Wave Scattering Problem
Authors: Ko William L. , Karlsson Thorbjorn
Published: October 2011

Interaction of a plane compressional step wave with a circular cylindrical obstacle embedded in an elastic medium is studied. The obstacle is rigid, stationary, and of infinite length. The incident wave travels in a direction perpendicular to the axis of the cylinder. Using Kirchhoff’s theorem, surface integral equations are formulated for the displacement potential derivatives in the scattered field and on the cylinder boundary. The wave-front solution obtained for the illuminated zone on the cylinder is identical to that obtained by high-frequency wave-front analysis. Boundary stresses in the shadow zone as well as the initial behavior of the wave-front stresses at the boundary between the illuminated and shadow zones are obtained. The integral equations for both illuminated and shadow-zone boundary stresses are reduced to successive linear matrix equations for numerical analysis. The numerical methods developed in this paper can be applied to interaction problems for obstacles of arbitrary geometrical configuration. They are also readily extended to the case where the medium exhibits bilinear or multilinear stress-strain behavior.
Axisymmetric Contact Stresses About a Smooth Elastic Sphere in an Infinite Solid Stressed Uniformly at Infinity
Authors: Wilson H. B. , Goree J. G.
Published: October 2011

An evaluation is made of non-Hertzian contact stresses occurring during partial separation between a smooth elastic spherical inclusion and a surrounding infinite medium subjected to two independent axisymmetric stress components at infinity. Modifications of an analysis by another author for a special case involving a rigid inclusion and uniaxial tension applied at infinity are discussed, and an alternate method of solution is given. Extensive numerical results are presented for circumferential and normal stresses on the cavity corresponding to 12 different combinations of loading and elastic parameters which yield contact surfaces defined by either an equatorial spherical band or two polar spherical caps.
The cp for Accelerated Slender Bodies
Authors: Foote J. R.
Published: October 2011

The pressure coefficient is found by the acoustic theory for a class of slender bodies in uniform acceleration or deceleration to a given Mach number, subsonic or supersonic. Explicit formulas for the main pressure term, and for the first-order correction caused by the unsteady motion, are obtained for bodies which are perturbations from the basic parabolic profile. Examples are given of bodies contained in this theory, together with typical pressure-coefficient curves. Methods are given for selecting a pointed convex profile having its maximum cross section at any desired point lying within certain limits.
Dynamic Elastic Response of a Ring to Transient Pressure Loading
Authors: Suzuki Shin-Ichi
Published: October 2011

Stress analysis is carried out for distributed impact loads applied along the inner and outer edges of a ring. These loads are assumed to be of the form q(θ)e−αt. The relationships between the stresses at both edges, the dimensions, and time are obtained. The results show that the ratio μ of the stress under impact to that under static load is different from μ = 2. The problem is analyzed by using the Laplace transformation method.
The Effect of Longitudinal Oscillations on Free Convection From Vertical Surfaces
Authors: Eshghy Siavash , Arpaci V. S. , Clark J. A.
Published: October 2011

The free-convection flow along a vertical plate oscillating in its own plane is given analytical treatment. The basic equations of boundary-layer flow and heat transfer are linearized and the first three approximations are considered. The first approximation, being the case of steady-state free convection, is the classical problem of Schmidt and Beckman extended by Ostrach. The second approximation is the frequency response of the fluid temperature and velocity for which limiting solutions are obtained in two regions; namely, the regions of small and large ω* = ωδ2/ν where ω is the circular frequency, δ the steady-state velocity boundary-layer thickness, and ν the fluid kinematic viscosity. The approximate range of validity of the asymptotic solution is estimated in terms of parameter ω0* which is a function only of Prandtl number. Part of the third approximation is time independent and gives rise to a net change in the steady values of the wall heat flux and shear stress. It is found that within the domain of laminar flow this net change is a decrease for the rate of heat transfer and an increase for the shear stress both evaluated for large values of ω0*. Heat-transfer measurements are made for a vertical cylinder in air. It is found that in the laminar regime the average coefficient of heat transfer experiences a slight decrease relative to its measured steady state value. For higher values of oscillatory velocity amplitude the average coefficient of heat transfer undergoes an increase over its measured steady-state value. This reversal in the behavior of average coefficient of heat transfer appears to be due to flow transition which is confirmed by smoke studies along a vertical cylinder.
Thermoelasticity When the Material Coupling Parameter Equals Unity
Authors: Dillon O. W.
Published: October 2011

Analytical solutions of three problems in coupled thermoelasticity are presented for the case when the material coupling parameter equals unity. The problems considered are: (a) Danilovskaya’s problem of a step function in temperature at the surface; (b) a step function in surface strain; and (c) constant velocity impact. Solutions are presented for the case of thin bars (one-dimensional stress) and are obtained by the Laplace-transform technique. There is great simplification in the equations when the material coupling parameter equals unity which permits the straightforward inversion of the transformed solutions. The results demonstrate significant deviations from the corresponding uncoupled solutions.
Torsional Buckling of an Extended Twisted Cylindrical Rod Under One-Sided Constraint
Authors: Williams W. O. , Paslay P. R.
Published: October 2011

The stability criteria for an infinitesimally extended finitely twisted cylindrical rod resting upon a rigid frictionless plane inclined with respect to a gravity field are determined. It is found that the initial position, in which the centerline of the rod is straight, is one of classically stable equilibrium but that instabilities may develop for sufficiently large displacements from that configuration. Thus buckling may occur if imperfections of the rod or other extraneous displacements of sufficient magnitude are present.
Longitudinal Sloshing of Liquid in a Flexible Hemispherical Tank
Authors: Hwang Chintsun
Published: October 2011

The paper deals with the longitudinal sloshing of liquid in a flexible hemispherical tank supported along the edge. The axisymmetrical sloshing modes of a rigid hemispherical tank are first established using the kernel-function approach. Potential functions are introduced considering both the liquid sloshing modes and the shell-liquid interaction modes. Lagrange’s equation is used to establish the dynamic response of the system. The numerical data indicate that in general the intercoupling between the shell-liquid mode and the liquid longitudinal sloshing mode is weak. The amplitudes of liquid sloshing are found to be relatively small under perfectly axisymmetrical loading conditions.
A Generalized Taylor Hypothesis With Application for High Reynolds Number Turbulent Shear Flows
Authors: Heskestad Gunnar
Published: October 2011

An approximate relation between the partial time and space derivatives of the velocity in a high Reynolds number turbulent shear flow (where high turbulence intensities prevail) is obtained. The relation is used to compute the mean-square space derirative from the mean-square time derivative, the latter being more accessible by hot-wire techniques.
Some Secondary Effects in a Simple Piping Structure Under Heating
Authors: Brock John E.
Published: October 2011

An analysis is made of an ell-shaped piping configuration subjected to uniform heating in order to assess the effect of secondary influences (axial deformation, shear, beam-column action, and difference between arc and chord) in relieving reactions.
On the Existence of a Cycloidal Burmester Theory in Planar Kinematics
Authors: Sandor George N.
Published: October 2011

One of the basic theories of kinematic synthesis, namely, Burmester’s classical centerpoint-circlepoint theory, is shown to be one of several special cases of a broader, more general new theory, involving points of the moving plane whose several corresponding positions lie on cycloidal curves. These curves may be generated by “cycloidal cranks.” Such “cycloidpoints,” centers of their generating circles (“circlepoints”) and base circles (“centerpoints”) are proposed to be called “Burmester point trios” (BPT’s). In case of 6 prescribed arbitrary positions, such BPT’s appear to lie, respectively, on three higher plane curves proposed to be called “cycloidpoint,” “circlepoint” and “centerpoint curves,” or, collectively, “generalized Burmester curves.” In the case of hypocycloidal cranks with “Cardanic” proportions, the hypocycloids become ellipses. For 7 prescribed positions, the number of BPT’s is finite. Application to linkage synthesis for motion generation with prescribed order and timing is presented and cognate-motion generator linkages, based on multiple generation of cycloidal curves, are shown to exist. Analytical derivations are outlined for the equations of the “generalized Burmester curves,” and possible further specializations and generalizations are indicated.
Vibration of an Infinitely Extending Plate Resting on an Elastic Foundation
Authors: Ono Kazuyosi
Published: October 2011

Free vibrations and forced vibrations of an infinitely extending plate resting on an elastic foundation and carrying a mass are solved. Then the amplitudes of the free vibrations produced by an impulse applied to the mass on the plate are determined, and it is found that two kinds of vibration are produced in the plate: One is a free vibration and the other is a special vibration, which consists of an infinite number of free vibrations and resembles a damped oscillation.
On Some Systems of Equations Encountered in Thin Plate and Elasticity Theory
Authors: Conway H. D.
Published: October 2011

This article presents a method for treating the doubly infinite system of simultaneous equations encountered in the small-deflection bending of clamped plates, rectangular plates in a stale of plane-stress, and certain other problems in elasticity. This method consists essentially of satisfying the boundary conditions at discrete points rather than continuously along the boundaries. A numerical example for the clamped plate problem indicates that the method may give faster convergence than the usual method of treating the equations, in some cases.
An Exploratory Study of Three-Dimensional Photothermoelasticity
Authors: Tramposch Herbert , Gerard George
Published: October 2011

A sandwich technique which utilizes an embedded polariscope consisting of two sheets of polarizing material cemented within a plastic model was evaluated for application to three-dimensional photothermoelasticity. The evaluation included strength tests of cemented joints, photoelastic tests of simple bending models and a sphere, all under mechanical loading. The technique proved to be rather simple to apply particularly since the resulting fringe patterns are readily interpreted. The sandwich technique was then applied to thermal-stress problems associated with a thick-walled cylinder under steady-state conditions. The experimental results correlated well with theory. The results obtained indicate the general applicability of the sandwich technique to three-dimensional stress problems generated by mechanical or thermal loads. It is noted that since other experimental thermal-stress-analysis methods are not highly developed, photothermoelasticity would seem to be particularly useful.
On the Application of Variational Methods to Initial Value Problems in Dynamics
Authors: Stuiver W.
Published: October 2011

The variational formulation of the initial value problem is derived and used for the construction of a procedure for the determination of approximate solutions. For the case of periodic motion of simple oscillators this procedure is shown to reduce to conventional techniques.
Flexural Wave Propagation and Vibration of Laminated Rods and Beams
Authors: Saito Hideo , Sato Kiichi
Published: October 2011

In this paper, a study is made of the flexural, elastic-wave propagation and vibration of laminated rods and beams of sandwich construction. The problem is treated two-dimensionally, and the solution satisfies exactly the elasticity equations and the boundary conditions. The frequency equation obtained has multiple roots, and the dispersion curve consists of a number of branches corresponding to the fundamental and higher modes of vibration. Numerical examples are given for the beams composed of aluminum and plastics.
Buckling of Axially Compressed Long Cylindrical Shell With Elastic Core
Authors: Yao J. C.
Published: October 2011

This paper presents a theoretical solution to the problem of determining the buckling characteristics of an axially compressed, long, cylindrical shell which contains a solid or elastic core with a modulus lower than that of the shell. The buckling mode is assumed to be sinusoidal in both the axial and circumferential directions, with the bellows mode taken as a special case. Numerical results are obtained for the buckling characteristics of cylinders with solid cores. These results are found similar to those of P. Seide, who considered the bellows buckling mode.
The Second Fundamental Problem in Heat Transfer of Laminar Forced Convection
Authors: Tao L. N.
Published: October 2011

This paper is concerned with the heat-transfer problem of laminar forced convection in noncircular pipes with arbitrary heat generation and prescribed heat flux at the wall. This class of boundary-value problems with Neumann conditions is approached by the method of conformal mapping. The solutions in terms of two analytic functions are established. This greatly enlarges the possibilities of analyses to many configurations which are otherwise not easily attainable. The example of an indented pipe of cardioid section is investigated in detail.
Wave Propagation in an Elastic Beam or Plate on an Elastic Foundation
Authors: Lloyd J. R. , Miklowitz Julius
Published: October 2011

Presented is an analysis of wave propagation in an infinite elastic plate or beam on an elastic foundation, based on a comparison of frequency spectra (or wave-train solutions) from the exact equations and existing approximate bending theories. A distinct similarity is found between the spectrum representing the more exact theory of bending and the Rayleigh-Lamb spectrum for symmetric waves in a free elastic plate, including the existence of complex branches. Good agreement between the approximate theories and the exact equations is found for soft foundations under the usual restrictions on high-frequency, short waves.
A Method for Analyzing Axisymmetric Plates With Complicating Conditions
Authors: Brock J. E.
Published: October 2011

A method is described for the analysis of circular flat plates in which properties may be variable, the elasticity may be orthotopic, membrane forces may be significant, and variable temperatures may be involved. It is required, however, that axial symmetry be maintained. Essentially the method consists in making an assumption (normalized in a certain way) for the principal moment difference, integrating (by analytical or numerical procedures), to find slopes, and then determining the principal moments. From these an improved assumption can be made for the differences, and the process iterated until convergence is satisfactory. Two examples are included.
Harmonic Analysis of Spherical Four-Bar Mechanisms
Authors: Yang A. T.
Published: October 2011

Understanding the dynamic behavior of mechanisms, which is essential to their high-speed applications, demands a clear knowledge of the acceleration of the output relative to input. Such knowledge can be ascertained by means of harmonic analysis of the motion of mechanisms. This paper presents a harmonic analysis of a general spherical four-bar mechanism with application to Hooke’s joint, wobble-plate mechanism, and the spherical crank drive.
Graphitic carbon film formation under Ni templates by radio-frequency sputtering for transparent electrode applications
Authors: Lin Meng-Yu , Sheng Yung-Shuan , Chen Shu-Han , Su Ching-Yuan , Li Lain-Jong , Lin Shih-Yen
Published: October 2011

An alternate approach to the preparation of transfer-free graphitic carbon films is proposed in this paper. Using a standard radio-frequency sputtering system and a high-temperature annealing procedure, graphitic carbon films are prepared under Ni templates. The results demonstrate that carbon precipitation occurs at both Ni template interfaces. With repeated annealing procedures at 1100 °C, a sheet resistance of 1.36 × 104 Ω/□ can be achieved. Selective carbon film deposition has also been developed via pattern formation on the Ni templates. The results indicate the potential application of this method to transparent electrode formation.
A handheld fluorescence molecular tomography system for intraoperative optical imaging of tumor margins
Authors: Zhao Qing , Jiang Huabei , Cao Zehong , Yang Lily , Mao Hui , Lipowska Malgorzata
Published: October 2011

Purpose:

Accurate identification of tumor margins presents a major challenge in the surgical treatment of human cancers. Inability of complete removal of tumor lesions after surgery causes local recurrence and increases the incidence of developing tumor metastasis. It is clear that novel approaches that allow defining tumor margins intraoperatively for removal of small tumor lesions in the surgical cavity is critical for improving prognosis of cancer patients. To facilitate image‐guided surgery using targeted optical imaging probes, we have developed a reflection‐mode fluorescence molecular tomography (FMT) system with a handheld probe that is able to provide three‐dimensional tumor margin information.

Methods:

The imaging method and system were validated using both simulated and phantom experiments. We further examined the accuracy of the handheld FMT system in an orthotopic mouse mammary tumor model following systemic delivery of near‐infrared (NIR) dye‐labeled and urokinase plasminogen activator receptor targeted magnet iron oxide nanoparticles.

Results:

Our results show that when the targets are located within 5 mm beneath the surface of the media, fluorescent images can be reliably detected and reconstructed with an average positional error of 0.5 mm laterally and 1.5 mm axially. For in vivo imaging in the mouse tumor model, the location and size of the tumor detected by FMT correlated well with that measured by the magnetic resonance imaging (MRI).

Conclusions:

Our system can three‐dimensionally image targets located at a depth of up to 7 mm. Thein vivo results suggest that in combination with targeted optical imaging probes, this handheld FMT system can be potentially used as an intraoperative tool for the detection of tumor margins and for image‐guided surgery.
Identifying context-specific competencies required by community Australian Football sports trainers
Authors: Donaldson Alex , Finch Caroline F
Published: October 2011

Background

First-aid is a recommended injury prevention and risk management strategy in community sport; however, little is known about the sport-specific competencies required by first-aid providers.

Objective

To achieve expert consensus on the competencies required by community Australian Football (community-AF) sports trainers.

Study design

A three-round online Delphi process.

Setting

Community-AF.

Participants

16 Australian sports first-aid and community-AF experts.

Outcome measures

Rating of competencies as either ‘essential’, ‘expected’, ‘ideal’ or ‘not required’.

Results

After Round 3, 47 of the 77 (61%) competencies were endorsed as ‘essential’ or ‘expected’ for a sports trainer to effectively perform the activities required to the standards expected at a community-AF club by ≥75% of experts. These competencies covered: the role of the sports trainer; the responsibilities of the sports trainer; emergency management; injury and illness assessment and immediate management; taping; and injury prevention and risk management. Four competencies (5%) were endorsed as ‘ideal’ or ‘not required’ by ≥85% of experts and were excluded from further consideration. The 26 competencies where consensus was not reached were retained as second-tier, optional competencies.

Conclusions

Sports trainers are important members of on-field first-aid teams, providing support to both injured players and other sports medicine professionals. The competencies identified in this study provide the basis of a proposed two-tiered community-AF–specific sports trainer education structure that can be implemented by the peak sports body. This includes six mandatory modules, relating to the ‘required’ competencies, and a further six optional modules covering competencies on which consensus was not reached.
Cosmological New Massive Gravity and Galilean Conformal Algebra in 2 Dimensions
Authors: Setare M. R. , Kamali V.
Published: October 2011

We consider the realization of 2-dimensional Galilean conformal algebra (GCA2) on the boundary of cosmological new massive gravity. At first, we consider the contracted BTZ black hole solution. We obtain entropy formula for the GCA2in terms of contracted scaling dimension Δ and central chargeC1. This entropy formula exactly matches with the nonrelativistic limit of Bekenstein-Hawking entropy of BTZ black hole. Then, we extend our study to the contracted warped AdS3black hole solution of CNMG. We obtain the entropy of dual GCA2in terms of central charges and finite temperatures,T1,T2. Again, this expression coincides with the nonrelativistic limit of Bekenstein-Hawking entropy formula of warped AdS3black hole.
Deranged Bioenergetics and Defective Redox Capacity in T Lymphocytes and Neutrophils Are Related to Cellular Dysfunction and Increased Oxidative Stress in Patients with Active Systemic Lupus Erythematosus
Authors: Li Ko-Jen , Wu Cheng-Han , Hsieh Song-Chou , Lu Ming-Chi , Tsai Chang-Youh , Yu Chia-Li
Published: October 2011

Urinary excretion ofN-benzoyl-glycyl-Nε-(hexanonyl)lysine, a biomarker of oxidative stress, was higher in 26 patients with active systemic lupus erythematosus (SLE) than in 11 non-SLE patients with connective tissue diseases and in 14 healthy volunteers. We hypothesized that increased oxidative stress in active SLE might be attributable to deranged bioenergetics, defective reduction-oxidation (redox) capacity, or other factors. We demonstrated that, compared to normal cells, T lymphocytes (T) and polymorphonuclear neutrophils (PMN) of active SLE showed defective expression of facilitative glucose transporters GLUT-3 and GLUT-6, which led to increased intracellular basal lactate and decreased ATP production. In addition, the redox capacity, including intracellular GSH levels and the enzyme activity of glutathione peroxidase (GSH-Px) andγ-glutamyl-transpeptidase (GGT), was decreased in SLE-T. Compared to normal cells, SLE-PMN showed decreased intracellular GSH levels, and GGT enzyme activity was found in SLE-PMN and enhanced expression of CD53, a coprecipitating molecule for GGT. We conclude that deranged cellular bioenergetics and defective redox capacity in T and PMN are responsible for cellular immune dysfunction and are related to increased oxidative stress in active SLE patients.
LPA Receptor Heterodimerizes with CD97 to Amplify LPA-Initiated RHO-Dependent Signaling and Invasion in Prostate Cancer Cells
Authors: Ward Yvona , Lake Ross , Yin Juan Juan , Heger Christopher D. , Raffeld Mark , Goldsmith Paul K. , Merino Maria , Kelly Kathleen
Published: October 2011

CD97, an adhesion-linked G-protein–coupled receptor (GPCR), is induced in multiple epithelial cancer lineages. We address here the signaling properties and the functional significance of CD97 expression in prostate cancer. Our findings show that CD97 signals through Gα12/13 to increase RHO-GTP levels. CD97 functioned to mediate invasion in prostate cancer cells, at least in part, by associating with lysophosphatidic acid receptor 1 (LPAR1), leading to enhanced LPA-dependent RHO and extracellular signal–regulated kinase activation. Consistent with its role in invasion, depletion of CD97 in PC3 cells resulted in decreased bone metastasis without affecting subcutaneous tumor growth. Furthermore, CD97 heterodimerized and functionally synergized with LPAR1, a GPCR implicated in cancer progression. We also found that CD97 and LPAR expression were significantly correlated in clinical prostate cancer specimens. Taken together, these findings support the investigation of CD97 as a potential therapeutic cancer target. Cancer Res; 71(23); 7301–11. ©2011 AACR.
Acquisition of Resistance toward HYD1 Correlates with a Reduction in Cleaved α4 Integrin Expression and a Compromised CAM-DR Phenotype
Authors: Emmons Michael F. , Gebhard Anthony W. , Nair Rajesh R. , Baz Rachid , McLaughlin Mark L. , Cress Anne E. , Hazlehurst Lori A.
Published: October 2011

We recently reported that the β1 integrin antagonist, referred to as HYD1, induces necrotic cell death in myeloma cell lines as a single agent using in vitro and in vivo models. In this article, we sought to delineate the determinants of sensitivity and resistance toward HYD1-induced cell death. To this end, we developed an HYD1 isogenic resistant myeloma cell line by chronically exposing H929 myeloma cells to increasing concentrations of HYD1. Our data indicate that the acquisition of resistance toward HYD1 correlates with reduced levels of the cleaved α4 integrin subunit. Consistent with reduced VLA-4 (α4β1) expression, the resistant variant showed ablated functional binding to fibronectin, VCAM-1, and the bone marrow stroma cell line HS-5. The reduction in binding of the resistant cell line to HS-5 cells translated to a compromised cell adhesion-mediated drug resistant phenotype as shown by increased sensitivity to melphalan- and bortezomib-induced cell death in the bone marrow stroma coculture model of drug resistance. Importantly, we show that HYD1 is more potent in relapsed myeloma specimens than newly diagnosed patients, a finding that correlated with α4 integrin expression. Collectively, these data indicate that this novel d-amino acid peptide may represent a good candidate for pursuing clinical trials in relapsed myeloma and in particular patients with high levels of α4 integrin. Moreover, our data provide further rationale for continued preclinical development of HYD1 and analogues of HYD1 for the treatment of multiple myeloma and potentially other tumors that home and/or metastasize to the bone. Mol Cancer Ther; 10(12); 2257–66. ©2011 AACR.
Heparin Strongly Induces Soluble Fms-Like Tyrosine Kinase 1 Release In Vivo and In Vitro—Brief Report
Authors: Searle Julia , Mockel Martin , Gwosc Stefanie , Datwyler Saul A. , Qadri Fatimunnisa , Albert Gesa I. , Holert Fabian , Isbruch Annette , Klug Lars , Muller Dominik N. , Dechend Ralf , Muller Reinhold , Vollert Joern O. , Slagman Anna , Mueller Christian , Herse Florian
Published: October 2011

Objective—

Soluble fms-like tyrosine kinase 1 (sFlt1) is involved in the pathophysiology of preeclampsia and coronary artery disease. Because sFlt1 has a heparin-binding site, we investigated whether or not heparin releases sFlt1 from the extracellular matrix.

Methods and Results—

We measured sFlt1 before and after heparin administration in 135 patients undergoing coronary angiography, percutanous coronary intervention, or both. sFlt1 was increased directly after heparin administration (from 254 to 13 440 pg/mL) and returned to baseline within 10 hours. Umbilical veins and endothelial cells treated with heparin released sFlt1. Heparinase I and III also increased sFlt1. Mice treated with heparin had elevated sFlt1 serum levels. Their serum inhibited endothelial tube formation.

Conclusion—

Heparin releases sFlt1 by displacing the sFlt1 heparin-binding site from heparan sulfate proteoglycans. Heparin could induce an antiangiogenic state.
The β-Chain of Cell Surface F
0
F
1
ATPase Modulates ApoA-I and HDL Transcytosis Through Aortic Endothelial Cells
Authors: Cavelier Clara , Ohnsorg Pascale M. , Rohrer Lucia , von Eckardstein Arnold
Published: October 2011

Objective—

Both HDLs and their major protein constituent apolipoprotein A-I (apoA-I) are transported through aortic endothelial cells. The knock-down of the ATP-binding cassette transporters A1 (ABCA1), G1 (ABCG1), and of the scavenger receptor-BI (SR-BI) diminishes but does not completely block the transport of apoA-I or HDL, so that other receptors appear to be involved. The ectopic β-chain of F
0
F
1
ATPase has been previously characterized as an apoA-I receptor, triggering HDL internalization in hepatocytes.

Methods and Results—

The ectopic presence of the β-chain of F
0
F
1
ATPase on the surface of endothelial cells was confirmed by cell surface biotinylation. RNA-interference and the F
0
F
1
ATPase inhibitory peptide IF
1
reduced cell binding of apoA-I but not HDL, as well as association and transendothelial transport of both apoA-I and HDL. Furthermore, apoA-I stimulated F
0
F
1
ATPase catalyzed ATP hydrolysis. The generated ADP as well as apoA-I stimulated the binding, cell association, and internalization of HDL. Both in the presence and absence of ADP inhibition of the purinergic receptor P2Y
12
but not P2Y
1
decreased the cell association of apoA-I and HDL. Coinhibition of β-ATPase and ABCA1 had no additive effects on the cell association and transport of apoA-I. Reduced cell association of HDL by β-ATPase inhibition was not further decreased by additional knock-down of ABCG1 or SR-BI.

Conclusion—

Binding of apoA-I to ectopic F
0
F
1
ATPase triggers the generation of ADP, which via activation of the purinergic receptor P2Y
12
stimulates the uptake and transport of HDL and initially lipid-free apoA-I by endothelial cells.
Low-Energy Multistage Atrial Defibrillation Therapy Terminates Atrial Fibrillation With Less Energy Than a Single Shock
Authors: Li Wenwen , Janardhan Ajit H. , Fedorov Vadim V. , Sha Qun , Schuessler Richard B. , Efimov Igor R.
Published: October 2011

Background—

Implantable device therapy of atrial fibrillation (AF) is limited by pain from high-energy shocks. We developed a low-energy multistage defibrillation therapy and tested it in a canine model of AF.

Methods and Results—

AF was induced by burst pacing during vagus nerve stimulation. Our novel defibrillation therapy consisted of 3 stages: stage (ST) 1 (1–4 low-energy biphasic [BP] shocks), ST2 (6–10 ultralow-energy monophasic [MP] shocks), and ST3 (antitachycardia pacing). First, ST1 testing compared single or multiple MP and BP shocks. Second, several multistage therapies were tested: ST1 versus ST1+ST3 versus ST1+ST2+ST3. Third, 3 shock vectors were compared: superior vena cava to distal coronary sinus, proximal coronary sinus to left atrial appendage, and right atrial appendage to left atrial appendage. The atrial defibrillation threshold (DFT) of 1 BP shock was <1 MP shock (0.55±0.1 versus 1.38±0.31 J,
P
=0.003). Two to 3 BP shocks terminated AF with lower peak voltage than 1 BP or 1 MP shock and with lower atrial DFT than 4 BP shocks. Compared with ST1 therapy alone, ST1+ST3 lowered the atrial DFT moderately (0.51±0.46 versus 0.95±0.32 J,
P
=0.036), whereas 3-stage therapy (ST1+ST2+ST3) dramatically lowered the atrial DFT (0.19±0.12 versus 0.95±0.32 J for ST1 alone,
P
=0.0012). Finally, the 3-stage therapy was equally effective for all studied vectors.

Conclusions—

Three-stage electrotherapy significantly reduces the AF DFT and opens the door to low-energy atrial defibrillation at or below the pain threshold.