bluuebunny/crossref_metadata_2025_split huggingface dataset:
A mutation in Zeaxanthin epoxidase contributes to orange coloration and alters carotenoid contents in pepper fruit (Capsicum annuum)
Authors: Lee Seo‐Young , Jang So‐Jeong , Jeong Hyo‐Bong , Lee Se‐Young , Venkatesh Jelli , Lee Joung‐Ho , Kwon Jin‐Kyung , Kang Byoung‐Cheorl 
Published: April 2021

SUMMARYPhytoene synthase (PSY1), capsanthin‐capsorubin synthase (CCS), and pseudo‐response regulator 2 (PRR2) are three major genes controlling fruit color in pepper (Capsicum spp.). However, the diversity of fruit color in pepper cannot be completely explained by these three genes. Here, we used an F2 population derived from Capsicum annuum ‘SNU‐mini Orange’ (SO) and C. annuum ‘SNU‐mini Yellow’ (SY), both harboring functional PSY1 and mutated CCS, and observed that yellow color was dominant over orange color. We performed genotyping‐by‐sequencing and mapped the genetic locus to a 6.8‐Mb region on chromosome 2, which we named CaOr. We discovered a splicing mutation in the zeaxanthin epoxidase (ZEP) gene within this region leading to a premature stop codon. HPLC analysis showed that SO contained higher amounts of zeaxanthin and total carotenoids in mature fruits than SY. A color complementation assay using Escherichia coli harboring carotenoid biosynthetic genes showed that the mutant ZEP protein had reduced enzymatic activity. Transmission electron microscopy of plastids revealed that the ZEP mutation affected plastid development with more rod‐shaped inner membrane structures in chromoplasts of mature SO fruits. To validate the role of ZEP in fruit color formation, we performed virus‐induced gene silencing of ZEP in the yellow‐fruit cultivar C. annuum ‘Micropep Yellow’ (MY). The silencing of ZEP caused significant changes in the ratios of zeaxanthin to its downstream products and increased total carotenoid contents. Thus, we conclude that the ZEP genotype can determine orange or yellow mature fruit color in pepper.
Influence of Rotatory Inertia and Shear on Flexural Motions of Isotropic, Elastic Plates
Authors: Mindlin R. D. 
Published: April 2021

Abstract
A two-dimensional theory of flexural motions of isotropic, elastic plates is deduced from the three-dimensional equations of elasticity. The theory includes the effects of rotatory inertia and shear in the same manner as Timoshenko’s one-dimensional theory of bars. Velocities of straight-crested waves are computed and found to agree with those obtained from the three-dimensional theory. A uniqueness theorem reveals that three edge conditions are required.
Free Vibrations of a Pin-Ended Column With Constant Distance Between Pin Ends
Authors: Burgreen David 
Published: April 2021

Abstract
In this paper a study is made of the free vibrations of a pin-ended column whose ends are pinned to points fixed in space. This imposes the condition of constant end distance instead of the usual theoretical assumption that the load on the column remains constant. The differential equation of the system is nonlinear, and, with the assumptions that are made, is found to have an exact solution in terms of elliptic functions. Dependent upon the initial amplitude of deflection and the compressive load on the column, several types of vibrations are found to exist. The variation of frequency and wave form with the load-amplitude parameter is discussed. In particular, it is found that the frequency is dependent upon the amplitude of vibration, the effect of the amplitude of vibration becoming more pronounced as the Euler load is approached. For a column under the Euler load the classical theory gives the frequency of vibration as zero. The present theory shows that for finite amplitudes of vibration the frequency is not zero. Experimental results are presented, and a comparison of the theoretical and experimental frequencies and wave shapes is made.
Large-Deflection Theory for Plates With Small Initial Curvature Loaded in Edge Compression
Authors: Coan J. M. 
Published: April 2021

Abstract
This investigation of the buckling of a simply supported, rectangular isotropic plate with small initial curvature was undertaken to evaluate current procedures for deducing the true (flat plate) critical load from the measured deflections and strains of a nominally flat plate. The boundary conditions are those that are usually met in test practice but which have not been satisfied by earlier studies, i.e., stress-free supported edges and uniformly displaced loaded edges. Previous solutions require a distribution of transverse stress along the supported edges sufficient to keep them straight and parallel at all times. However, in most test specimens, the freedom of the supported edges to distort in the plane of the plate measurably influences the behavior of the plate and the stress distribution within it. Levy’s solution of von Kármán’s “large deflection” equations is adapted by the author to yield the nonuniform edge displacements that are characteristic of stress-free supported edges. Limited experimental evidence tends to confirm the predictions of this analysis.
A Fourier Integral Solution for the Plane-Stress Problem of a Circular Ring With Concentrated Radial Loads
Authors: Nelson Carl W. 
Published: April 2021

Abstract
A Fourier integral solution for the stresses in a straight bar of uniform cross section loaded by various combinations of loads applied normally to the edges of the bar was published by L. N. G. Filon in 1903 (3). Solutions for the stresses in circular rings, loaded on one or both boundaries by radial loads, have been limited to Fourier-series solutions for closed circular rings (1, 12, 13, 14, 15), except that solutions in closed form have been obtained for the limiting cases which occur either when the inner radius becomes very small or when the outer radius becomes very large. This paper presents a Fourier integral solution for the plane-stress problem of a curved bar bounded by two concentric circles and loaded by radial loads on the circular boundaries. It treats only the particular case of a curved bar in equilibrium under the action of two equal and opposite radial forces, one on each boundary. However, the method can be extended so as to deal with other combinations of loads. Sufficient numerical results are given to show that the Fourier integral method permits the calculation of numerical values of the stresses in the particular case considered. It is the purpose of this paper to show that the Fourier integral method can be used successfully in what is probably the simplest problem of concentrated loads acting on a curved bar and to furnish a background of material for use in less simple problems such as bending of curved bars due to concentrated loads.
The Propagation of Longitudinal Waves of Plastic Deformation in a Bar of Material Exhibiting a Strain-Rate Effect
Authors: Malvern L. E. 
Published: April 2021

Abstract
The theory of propagation of longitudinal waves of plastic deformation is extended to apply to materials in which the stress is a function of the instantaneous plastic strain and strain rate. Solutions are given for an idealized flow law and compared with solutions based upon earlier theories which neglect strain-rate effect.
On the Extrusion of a Very Viscous Liquid
Authors: Weil Herschel 
Published: April 2021

Abstract
An approximation to a state of affairs occurring in the extrusion of rubber is the two-dimensional slow flow of a very viscous liquid from a half plane into a semi-infinite strip. The region surrounding the orifice or juncture of the strip and plane corresponds to the region where the extruded rubber is forced from a die box into a die. Methods are developed and carried out for numerically obtaining the stream function, the velocity components, and the pressure in this region. The general pattern of the streamlines is determined, and it is found in what way and to what extent the flow pattern in the strip near the orifice differs from plane Poiseuille flow and how far into the strip this difference is significant.
Incidental to this work, it was necessary to determine the first several complex roots of sin A = ± 2 3 π A . This information is useful apart from the flow problem, and the results are tabulated.
On the Stability of Plates Reinforced by Longitudinal Ribs
Authors: Klitchieff J. M. 
Published: April 2021

Abstract
The stability of plates reinforced by any number of equal and equidistant longitudinal ribs has been considered. By transformation of the system of equations established by S. Timoshenko the general solution of it has been developed, giving directly the rigidity of ribs required to secure any given critical compressive force of the plate. Two numerical examples of stiffenings used in ship design have been discussed.
Bending of a Circular Beam Resting on an Elastic Foundation
Authors: Volterra Enrico 
Published: April 2021

Abstract
Saint Venant’s equations (1) for a circular beam, bent out of its plane of initial curvature, are applied to the study of the deflections of beams resting on elastic foundations and loaded by concentrated symmetric forces. The solution of the problem is given in explicit form, and tables for the deflections, angles of twist, bending and twisting moments are presented.
An Electrical Method for Determining Journal-Bearing Characteristics
Authors: Carter D. S. 
Published: April 2021

Abstract
More than half a century has passed since Osborne Reynolds employed hydrodynamic principles to derive his well-known differential equation for the pressure distribution in a thin film of viscous fluid under shear. During that time many ingenious methods have been put forward for the solution of Reynolds equation in cases of engineering interest. These methods have been found useful in the few cases to which they have been applied; but none is adaptable to the production, in quantity, of much-needed data. Any future program for the preparation of a comprehensive set of bearing data will surely be carried out with the help of the large, modern, rapid-calculating machines. Until these machines become more readily available, however, the need will remain for improved calculational techniques which require only modest financial and material resources. It was with this need in mind that the work described in the present paper was undertaken.
The Limit Design of a Transversely Loaded Square Grid
Authors: Heyman Jacques 
Published: April 2021

Abstract
An earlier paper discussed the derivation of a breakdown criterion for beams subjected to combined bending and torsion. The present paper deals with the limit design of grids, formed by two sets of parallel beams intersecting at right angles, subjected to transverse loading at the joints. This form of loading introduces both bending and twisting moments in the beams, and modes of failure under these combined actions are investigated. Exact solutions are determined for some simple grids, but general methods are demonstrated which lead to upper and lower bounds on the collapse load.
Torsion of a Circular Shaft With Diametrically Opposite Flat Sides
Authors: Carter W. J. , Oliphint J. B. 
Published: April 2021

Abstract
The solutions for torsional stress and torsional stiffness of circular shafts with flat sides which are presented in this paper have been obtained by means of the relaxation technique. The solutions for both shear stress and torsional stiffness are given for four ratios of flat side dimension to diameter of the shaft. The stress for a very small flat has been obtained by use of a hydrodynamic analogy to the torsion problem. A comparison of the results obtained is made with those given by Ōkubo.
Investigation of Annular Liquid Flow With Cocurrent Air Flow in Horizontal Tubes
Authors: Abramson A. E. 
Published: April 2021

Abstract
Visual observations and flow analysis were made of annular liquid flow with cocurrent air flow in horizontal tubes. The effect of liquid properties and air-stream conditions on the characteristics of the liquid flow were observed. The results are presented in form of shadowgraph pictures of the liquid flow. Analysis of the flow system related the characteristics of the liquid flow to the flow conditions.
An Airy Integral Analysis of Beam Columns With Distributed Axial Loading Having a Fixed Line of Action
Authors: Tyler C. M. , Christiano J. G. 
Published: April 2021

Abstract
An analytic method of solution of beam columns with partial uniformly distributed axial loading whose line of action does not change as the column deflects is developed in terms of Airy integral functions. This method is valid when the beam bending moment can be expressed or approximated piecewise as a polynomial. A numerical example is included and also tables of the necessary Airy integral functions and their first derivatives.
The Concept of Complex Damping
Authors: Myklestad N. O. 
Published: April 2021

Abstract
In this paper it is shown that if the hysteresis loop for a material has a particular shape the damping can be considered adequately by multiplying the modulus of elasticity of the material by the complex number e2bi where 2b is called the complex damping factor. For small values of b it is shown that both for free and forced vibrations of a simple spring-mass system the motion in the case of complex damping is the same as in the case of viscous damping, with b = c/ccr, except that in the steady-state case the phase angles are slightly different. Also, it is shown how complex damping may be applied to cases of forced vibrations of uniform rods and beams. The greatest advantage of using complex damping, however, is in numerical calculations of forced vibrations of engine crankshafts, airplane wings, and other types of structures; and for such calculations it already has been extensively used.
Large Plastic Deformations of Beams Under Transverse Impact
Authors: Lee E. H. , Symonds P. S. 
Published: April 2021

Abstract
A comparatively simple method of analysis is developed to determine the deformations in a beam subjected to lateral impact of such a magnitude that plastic strains large compared with elastic strains occur. A useful approximation to the motion then can be obtained by neglecting elastic strains and considering rigid-body motion of segments of the beam joined at plastic hinges where the entire deformation takes place. A method of analyzing such a situation is described and applied to a beam subjected to central impact. The approximate final permanent deformation is obtained; this includes deformation during application of the load, and plastic flow which continues afterward when the kinetic energy of the motion generated by the impact is transformed into additional plastic deformation. A criterion is given for conditions when this type of theory can be expected to provide a satisfactory analysis. The method of solution provides an interesting analogy to the concept of static determinacy which has been used in the analysis of quasi-static plastic-flow problems.
The Free Oscillation of the Centrifugal Pendulum With Wide Angles
Authors: Crossley F. R. E. 
Published: April 2021

Abstract
The pendulum torsional vibration absorber, designed usually in the bifilar form, has proved very effective in its purpose, especially in radial aircraft engines. The ordinary theory is based on an assumption of small angles of swing of the pendulum, and this assumption simplifies the equations of motion to linear form. However, wide angles of swing have actually been observed in most installations. Two previous analyses have been made of the wide angle swing, but have shown only the usual lengthening of the period due to wide swing of a gravity-controlled pendulum. Here it is demonstrated that the longer period due to wide angles will be offset by taking a heavier pendulum on a given carrier, for this shortens the period tremendously, as shown in Fig. 2.
Thin Rectangular Plates on Elastic Foundation
Authors: Fletcher H. J. , Thorne C. J. 
Published: April 2021

Abstract
The deflection of a thin rectangular plate on an elastic foundation is given for the case in which two opposite edges have arbitrary but given deflections and moments. Six important cases of boundary conditions on the remaining two edges are treated. The solution is given for general transverse loads which are continuous in one direction and sectionally continuous in the other. By use of the sine transform the solution is obtained as a single trigonometric series. Numerical solutions are obtained for six special cases.
A Nonlinear Problem in the Bending Vibration of a Rotating Beam
Authors: Lo Hsu 
Published: April 2021

Abstract
The problem of bending vibration of a rotating beam is a nonlinear one when the vibration takes place in a plane not perpendicular to the plane of rotation. The nonlinear term arises from the Coriolis acceleration. From the nonlinear equation established, it is found that the existence of periodic solutions depends on the initial conditions, and the most important parameter which affects the periodic solutions is the nondimensional amplitude Ā. The percentage error in the frequency of vibration due to neglect of the Coriolis acceleration is a function of the parameter Ā only. For most of the present-day applications the error is negligible.
Determination of Theoretical Plastic Stress-Strain Relations for Variable Combined Stress Ratios
Authors: Hu L. W. , Marin Joseph 
Published: April 2021

Abstract
To distinguish between the various theories of plastic flow defining plastic stress-strain relations under combined stresses, it is necessary to conduct combined stress tests in which the ratio of the stress components does not remain constant during the test. To compare these results with the flow theory of the second stress-invariant type, graphical methods have been used to determine the combined plastic stress-strain relations based upon the simple tension plastic stress-strain relations. This paper presents an analytical procedure for the determination of these theoretical stress-strain relations. For certain stress conditions the graphical methods have the disadvantage of yielding inaccurate results—an objection not present in the proposed method. Furthermore, the proposed analytical method is less time-consuming than the graphical methods.
On Longitudinal Plane Waves of Elastic-Plastic Strain in Solids
Authors: Wood D. S. 
Published: April 2021

Abstract
A theoretical description is given for the propagation of longitudinal plane waves of large lateral extent in solids, for waves of plastic as well as elastic strain. The importance of the hydrostatic compressibility in determining the nature of the waves is brought out. The results are illustrated by a computation of the velocities of propagation of such waves in 24S-T aluminum alloy, and by a computation of the propagation of a pressure pulse of short duration through a flat plate. The later results illustrate the attenuation and change in shape of the pressure pulse during its propagation. The effects of the pressure dependence of the compressibility, the temperature changes accompanying compression, and the time and rate dependence of the mechanical properties, upon the propagation of such waves are discussed qualitatively.
On a General Method of Solving Second-Order Ordinary Differential Equations by Phase-Plane Displacements
Authors: Jacobsen L. S. 
Published: April 2021

Abstract
The phase-plane-delta method of solving second-order differential equations has been illustrated by numerous examples involving graphical constructions. Test cases show good accuracy for practicable size of steps, but, in general, the degree of approximation can be inferred empirically only. The delta method is extremely simple to apply, even to complicated equations. A subprofessional assistant can be instructed quickly in how to use the method, and ordinarily will develop enough speed to become useful in a short time.
Torsion of Uniform Rods With Particular Reference to Rods of Triangular Cross Section
Authors: Nuttall Henry 
Published: April 2021

Abstract
A solution of the Saint-Venant torsion problem is presented which is alternative to that usually adopted. When the cross section has the shape of an isosceles triangle the method also provides a close and useful Rayleigh-Ritz solution. The torsional rigidity has been evaluated for a range of section proportions, and simple expressions for an approximate evaluation of the maximum shearing stress are provided. Use is made of the hydrodynamic analogy to extend the application of these solutions to the problem of the flow of a viscous incompressible fluid in a tube of triangular section.
Fabrication and Testing of Bioinspired Surface Designs for Friction Reduction at the Piston Ring and Liner Interface
Authors: Maddox Shelby R. , Gangopadhyay Arup , Ghaednia Hamed , Cai Jiyu , Han Xiaoxiao , Meng Xiangbo , Goss Josue A. , Zou Min 
Published: April 2021

Abstract
The piston ring and liner interface is a major source of friction loss in automotive combustion engines. This loss can be mitigated by learning from surfaces from nature that manipulate friction. In this study, novel fabrication and testing methods were developed and used to efficiently compare three-dimensional bioinspired surface designs to existing piston liner surface topographies. Surface designs inspired by frog toes were fabricated using two-photon lithography, and their frictional performance is compared to that of typical piston liner topography. These designs reduce surface friction by an average of 18%, and up to 39%, compared to a flat control. The developed fabrication and testing methods allow comparison with existing topographies without needing to transfer the designs to the original materials and provide an efficient approach for designing surfaces to meet the frictional challenges of the future.
Design and Bending Analysis of a Metamorphic Parallel Twisted-Scissor Mechanism
Authors: Suthar Bhivraj , Jung Seul 
Published: April 2021

Abstract
The conventional scissor mechanism is used in modern engineering and robotic applications due to its metamorphic ability. The folding configuration provides space-saving and unfolding provides longer linear expansion capability. However, a conventional scissor suffers unexpected and uncontrolled large bending deformation due to low bending stiffness while unfolding configuration, which may damage its structure. It also has a sudden bending singularity during unfolding, which may also damage the actuator. These limitations impose a significant constraint on real-life applications such as foldable robot arms, space robot arms, and reconfigurable robots. In this paper, we proposed a multi-strands parallel twisted-scissor mechanism (PTSM) to enhance its usability. The PTSM is inspired by a rope structure and designed by introducing a metamorphic segment (MS) using the S-shaped linkage design approach to improve its bending stiffness without affecting conventional scissors’ fundamentals. The PTSM has a unique feature of several automatic-link locking mechanisms to avoid singularity without using additional sensors, mechanism, or control. We experimentally checked the proposed design’s functionality and its feasibility. We formulated a cantilever bending model for foldable PTSM with N metamorphic segments considering revolute joint clearance for bending estimation, experimentally verified, and analyzed the bending deformation in the X–Y and Y–Z planes. Also, it is compared with a conventional scissor. Finally, we found that PTSM is stronger than conventional scissor and can fold/unfold smoothly using a single linear actuator. PTSM can provide large linear displacement with small bending deformation without bending singularity.