bluuebunny/crossref_metadata_2025 huggingface dataset:
CsubMADS1, a lag phase transcription factor, controls development of polar eukaryotic microalga Coccomyxa subellipsoidea C‐169
Authors: Nayar Saraswati , Thangavel Gokilavani
Published: June 2021

MADS‐box transcription factors (TFs) have not been functionally delineated in microalgae. In this study, the role of CsubMADS1 from microalga Coccomyxa subellipsoidea C‐169 has been explored. Unlike Type II MADS‐box proteins of seed plants with MADS, Intervening, K‐box, and C domains, CsubMADS1 only has MADS and Intervening domains. It forms a group with MADS TFs from algae in the phylogenetic tree within the Type II MIKCC clade. CsubMADS1 is expressed strongly in the lag phase of growth. The CsubMADS1 monomer does not have a specific localization in the nucleus, and it forms homodimers to localize exclusively in the nucleus. The monomer has two nuclear localization signals (NLSs): an N‐terminal NLS and an internal NLS. The internal NLS is functional, and the homodimer requires two NLSs for specific nuclear localization. Overexpression (OX) of CsubMADS1 slows down the growth of the culture and leads to the creation of giant polyploid multinucleate cells, resembling autospore mother cells. This implies that the release of autospores from autospore mother cells may be delayed. Thus, in wild‐type (WT) cells, CsubMADS1 may play a crucial role in slowing down growth during the lag phase. Due to starvation in 2‐month‐old colonies on solid media, the WT colonies produce mucilage, whereas OX colonies produce significantly less mucilage. Thus, CsubMADS1 also negatively regulates stress‐induced mucilage production and probably plays a role in stress tolerance during the lag phase. Taken together, our results reveal that CsubMADS1 is a key TF involved in the development and stress tolerance of this polar microalga.
Time‐series transcriptomics reveals a BBX32‐directed control of acclimation to high light in mature Arabidopsis leaves
Authors: Alvarez‐Fernandez Ruben , Penfold Christopher A. , Galvez‐Valdivieso Gregorio , Exposito‐Rodriguez Marino , Stallard Ellie J. , Bowden Laura , Moore Jonathan D. , Mead Andrew , Davey Phillip A. , Matthews Jack S. A. , Beynon Jim , Buchanan‐Wollaston Vicky , Wild David L. , Lawson Tracy , Bechtold Ulrike , Denby Katherine J. , Mullineaux Philip M.
Published: June 2021

The photosynthetic capacity of mature leaves increases after several days’ exposure to constant or intermittent episodes of high light (HL) and is manifested primarily as changes in chloroplast physiology. How this chloroplast‐level acclimation to HL is initiated and controlled is unknown. From expanded Arabidopsis leaves, we determined HL‐dependent changes in transcript abundance of 3844 genes in a 0–6 h time‐series transcriptomics experiment. It was hypothesized that among such genes were those that contribute to the initiation of HL acclimation. By focusing on differentially expressed transcription (co‐)factor genes and applying dynamic statistical modelling to the temporal transcriptomics data, a regulatory network of 47 predominantly photoreceptor‐regulated transcription (co‐)factor genes was inferred. The most connected gene in this network was B‐BOX DOMAIN CONTAINING PROTEIN32 (BBX32). Plants overexpressing BBX32 were strongly impaired in acclimation to HL and displayed perturbed expression of photosynthesis‐associated genes under LL and after exposure to HL. These observations led to demonstrating that as well as regulation of chloroplast‐level acclimation by BBX32, CRYPTOCHROME1, LONG HYPOCOTYL5, CONSTITUTIVELY PHOTOMORPHOGENIC1 and SUPPRESSOR OF PHYA‐105 are important. In addition, the BBX32‐centric gene regulatory network provides a view of the transcriptional control of acclimation in mature leaves distinct from other photoreceptor‐regulated processes, such as seedling photomorphogenesis.
The efficacy of ethnic specific blood groups genotyping for routine donor investigation and rare donor identification in Taiwan
Authors: Yang Meng‐Hua , Chen Jen‐Wei , Wei Sheng‐Tang , Hou Sheng‐Mou , Chen Yann‐Jang
Published: June 2021

Background

Large‐scale single nucleotide variation (SNV)‐based blood group genotyping assays have been made available for over a decade. Due to differences in ethnic groups, there is much diversity in clinically important blood group antigens and genetic variants. Here, we developed a robust matrix‐assisted laser desorption/ionization time‐of‐flight (MALDI‐TOF)‐based blood group genotyping method on MassARRAY system.

Study Design and Methods

A total of 1428 donors were enrolled into three groups: (a) reagent red cell donors; (b) rare donor or common antigen‐negative donors; and (c) group O, R1R1/R2R2 donors. Forty‐two SNVs were designed for determining nine blood groups, with X/Y chromosome in two multiplex reactions, on MassARRAY 96‐well format system. Further targeted sequence analyses were performed by Sanger sequencing.

Results

WHO reference reagent (NIBSC code: 11/214) was tested for concordance with the provided genotype results. Among the donors, concordance rate was over 99%. Alleles of important phenotypes such as Mi(a+), Di(a+), and Asian‐type DEL and alleles of rare blood groups such as Fy(a−), Jk(a−b−) and s− were screened. Three types of discrepancies were found. Serologically, the ‘N’ antigen was expressed on genetically MM with GYP*Mur red blood cells and caused genuine discrepancies (9.5%). Genetically, allele dropout (ADO) was caused by rare SNV in the primer for Ss genotype (2.1%) and partial insertion of RHD genes (0.9%) led to difficulties in predicting phenotypes.

Conclusion

Hemo panel module and MassARRAY System in 96‐well format showed good performance in terms of large‐scale blood group genotyping and phenotype predictions. Implementation of this method is effective for routine blood group genotype screening of donors.
Role of hydrogen sulfide in ventilatory responses to hypercapnia in the medullary raphe of adult rats
Authors: Sabino João Paulo Jacob , Oliveira Lucas Vaz de Castro , Soriano Renato Nery , Kwiatkoski Marcelo , Branco Luiz G. S. , da Silva Glauber S. F.
Published: June 2021

New Findings

What is the central question of this study?

There is evidence that H2S plays a role in the control of breathing: what are its actions on the ventilatory and thermoregulatory responses to hypercapnia via effects in the medullary raphe, a brainstem region that participates in the ventilatory adjustments to hypercapnia?

What is the main finding and its importance?

Hypercapnia increased the endogenous production of H2S in the medullary raphe. Inhibition of endogenous H2S attenuated the ventilatory response to hypercapnia in unanaesthetized rats, suggesting its excitatory action via the cystathionine β‐synthase–H2S pathway in the medullary raphe.

Hydrogen sulfide (H2S) has been recently recognized as a gasotransmitter alongside carbon monoxide (CO) and nitric oxide (NO). H2S seems to modulate the ventilatory and thermoregulatory responses to hypoxia and hypercapnia. However, the action of the H2S in the medullary raphe (MR) on the ventilatory responses to hypercapnia remains to be elucidated. The present study aimed to assess the role of H2S in the MR (a brainstem region that contains CO2‐sensitive cells and participates in the ventilatory adjustments to hypercapnia) in the ventilatory responses to hypercapnia in adult unanaesthetized Wistar rats. To do so, aminooxyacetic acid (AOA; a cystathionine β‐synthase (CBS) enzyme inhibitor), propargylglycine (PAG; a cystathionine γ‐lyase enzyme inhibitor) and sodium sulfide (Na2S; an H2S donor) were microinjected into the MR. Respiratory frequency (fR), tidal volume (VT), ventilation (), oxygen consumption () and body temperature (Tb) were measured under normocapnic (room air) and hypercapnic (7% CO2) conditions. H2S concentration within the MR was determined. Microinjection of the drugs did not affect fR, VT and during normocapnia when compared to the control group. However, the microinjection of AOA, but not PAG, attenuated fR and during hypercapnia in comparison to the vehicle group, but had no effects on Tb. In addition, we observed an increase in the endogenous production of H2S in the MR during hypercapnia. Our findings indicate that endogenously produced H2S in the MR plays an excitatory role in the ventilatory response to hypercapnia, acting through the CBS–H2S pathway.
A Sense of the Past: Historical Publications of the American Society of Mechanical Engineers
Authors: Ferguson Eugene S.
Published: June 2021

The American Society of Mechanical Engineers has both a tradition and a solid record of encouraging and supporting historical publications, particularly in the field of biography but also in the history of technical achievements. The numerous books, articles, and commemorative brochures that have been published under Society auspices or with the encouragement of the Society provide a great deal of historical information, much of which would not be otherwise available. These publications make collectively a substantial and tangible witness to the sense of the past that has inspired and, in some measure, informed a surprisingly large number of prominent individuals who are or have been members of the Society.
Engineering in the New Nation
Authors: Fehring Thomas H. , Reynolds Terry S.
Published: June 2021

One of the central facts about the early years of the United States is that the so-called industrial revolution was occurring in Britain at about the same time the thirteen colonies revolted against British rule and declared their independence. When the American Revolution ended in 1783, the new nation was, at it had been in the colonial period, overwhelmingly agrarian. Britain, meanwhile, was rapidly evolving into an industrial society. Many prominent figures in the new nation feared that while America had achieved political independence, it would become economically dependent on its former colonial master. It was in this context that early American mechanical innovators labored.
Land Transportation
Authors: Fehring Thomas H. , Reynolds Terry S.
Published: June 2021

The engineering involved in transportation provided one of the points from which the modern mechanical engineering profession in the United States emerged. The shops that produced the steam engines for river boats and the locomotives for railroads had, by the 1840s, become a leading training ground for the first generation of professional mechanical engineers. As railroads became the primary means of long-distance transport for goods in the late nineteenth century, they also became a leading employer of mechanical engineers. Not surprisingly, the Rail Transportation Division was one of the original eight divisions created when ASME in 1920 adopted a divisional organization; it remains among that organization’s most active divisions. Unfortunately, despite the rail industry’s importance to American history and to the history of mechanical engineering, few articles dealing with the history of this form of land transportation have appeared in Mechanical Engineering magazine over the past fifty years. None were selected for this volume.
The Nonlinear Bending of Thin Rods
Authors: Mitchell T. P.
Published: June 2021

The nonlinear bending of straight and circular-arc cantilevers under vertical and horizontal point loads is analyzed from a unified approach. Formulas for determining the deflected shape of the cantilevers are presented. Closed-form solutions are obtained for bending under two types of distributed loads. In particular, the problem of bending under a uniformly distributed normal load is solved.
Stresses and Deflections in an Elastically Restrained Circular Plate Under Uniform Normal Loading Over a Segment
Authors: Bassali W. A. , Nassif M.
Published: June 2021

Within the limits of the small-deflection plate theory and using complex variable methods, an exact expression is developed in series form for the solution of the problem of a thin circular plate elastically restrained along the boundary and subjected to uniform normal loading over a segment of the plate. The elastic constraint considered includes as particular cases the rigidly clamped and simply supported boundaries. For a rigidly clamped boundary the results are expressed in finite terms. Some details of calculations of deflections, moments, and shears based on the theory are provided in tables and curves. Timoshenko’s notation [1] is used in the paper. Other symbols will be defined as they appear in the text.
Transverse Flexure of a Thin Plate Containing Two Circular Holes
Authors: Tamate O.
Published: June 2021

The problem of finding stress resultants in a thin elastic plate containing two circular holes of equal size, under plain bending about the axes of symmetry, has been discussed on the basis of the Poisson-Kirchhoff theory. A method of perturbation is adopted for the determination of parametric coefficients involved in the solution. The factors of stress concentration are calculated and compared with the results available.
Plastic Stress-Strain Relationships—Some Experiments on the Effect of Loading Path and Loading History
Authors: Gill S. S. , Parker J.
Published: June 2021

Tests have been carried out on thin closed-ended tubes of alpha brass subjected to various combinations of torque and internal pressure. The effect of loading, unloading, and reloading along different loading paths has been investigated, including the effect on the shape of the yield surface, and the form of the curve of representative stress and representative strain. The behavior of the material for initial loading suggests that the material is isotropic in the plane of the surface of the tube but is anisotropic in a radial direction. A form of yield criterion and representative stress which correlates these results has been deduced, but the results of the tests for the second loadings of the specimens cannot be correlated in terms of a nested set of similar yield surfaces. The evidence for or against the existence of corners or pointed vertices on the yield surface is inconclusive.
An Experiment on Compressible-Flow Perturbations
Authors: d’Ews Thomson T. A. , Meyer R. E.
Published: June 2021

The effect which a slight tilting of the liners of a supersonic wind-tunnel nozzle has on the Mach-number distribution in the test-rhombus is determined on the basis of the linear-perturbation theory of reference [1]. Experiments are reported which (a) confirm that the first-order subsonic and transonic perturbations of the flow may be neglected compared with the supersonic perturbations, and (b) indicate that appreciable effects not accounted for by the first-order theory occur when the flow possesses high local pressure gradients.
Transient Film Condensation
Authors: Sparrow E. M. , Siegel R.
Published: June 2021

An analytical solution for transient laminar film condensation on a vertical plate is obtained using the method of characteristics. The situation considered is one in which the plate temperature, initially the same as that of the saturated vapor, is suddenly dropped. Results are obtained for transient heat-transfer coefficients and for the time required to achieve steady state.
Root-Locus Analysis of Structural Coupling in Control Systems
Authors: Cannon R. H.
Published: June 2021

When a feedback system is devised to control a mechanical member that is structurally limber, unstable (“self-excited”) vibrations may be encountered at approximately a natural frequency of the structural member. Cures are generally easy to effect once the phenomena are understood. Two interesting cases are described: ground vibrations of an airplane control system due to a limber fuselage, and vibrations of a stable platform system due to limberness in the platform structure. The investigations are carried out using the root-locus technique, which provides a plot of system characteristics as explicit functions of control strength. In the case of the stable platform, the analysis is found to be more reliable than physical intuition.
Normal Vibrations of a Uniform Plate Carrying Any Number of Finite Masses
Authors: Stokey W. F. , Zorowski C. F.
Published: June 2021

A general method is presented for determining approximately the natural frequencies of the normal vibrations of a uniform plate carrying any number of finite masses. Its application depends on knowing the frequencies and natural modes of vibration of the unloaded plate and the physical characteristics of the mass loadings. A numerical example is presented in detail in which this method is applied to a simply supported plate carrying two masses. Results also are included of experimentally measured frequencies for this configuration and several additional cases along with the frequencies computed using this method for comparison.
Stresses in a Stretched Slab Having a Spherical Cavity
Authors: Ling Chih-Bing
Published: June 2021

This paper presents an analytic solution for an infinite slab having a symmetrically located spherical cavity when it is stretched by an all-round tension. The required stress function is constructed by combining linearly two sets of periodic biharmonic functions and a biharmonic integral. The sets of biharmonic functions are derived from two fundamental functions specially built up for the purpose. The arbitrary functions involved in the biharmonic integral are first adjusted to satisfy the boundary conditions on the surfaces of the slab by applying the Hankel transform of zero order. Then the stress function is expanded in spherical co-ordinates and the boundary conditions on the surface of the cavity are satisfied by adjusting the coefficients of superposition attached to the sets of biharmonic functions. The resulting system of linear equations is solved by the method of successive approximations. The solution is finally illustrated by numerical examples for two radii of the cavity.
Influence Coefficients for Edge-Loaded Short, Thin, Conical Frustums
Authors: Baltrukonis J. H.
Published: June 2021

An exact solution is obtained in terms of Kelvin functions for axisymmetrically edge-loaded, short, thin, conical frustums. Expressions for the edge-deflectional and rotational influence coefficients are presented in matrix form. Approximate expressions for the influence coefficients are evolved by using one-term asymptotic expansions for the Kelvin functions. It is shown that the range of validity is somewhat larger for this approximate solution than for the solution by Horvay, Linkous, and Born.
Analysis of a Compression Test of a Model of a Granular Medium
Authors: Thurston C. W. , Deresiewicz H.
Published: June 2021

A granular medium is idealized here by a model composed of contiguous like spheres arranged in a face-centered cubic lattice. Total stress-strain relations for this model are derived by integrating incremental relations, given previously by Duffy and Mindlin, for a loading program which consists of a uniaxial compression applied concurrently with a related isotropic pressure. Further, the failure stress in uniaxial compression is determined as a function of initial pressure. Results of experimental work are reported which agree with predictions of the theory.
Creep of Thick-Walled Tubes Under Internal Pressure Considering Large Strains
Authors: Rimrott F. P. J.
Published: June 2021

Using the generally accepted assumptions of constant density, zero axial strain, and the distortion-energy law, equations are derived for the creep rates, strains, and stresses of a thick-walled, closed-end, circular, hollow cylinder under internal pressure and made of an isotropic and homogeneous material. The strains are considered large, requiring the use of the finite-strain theory. A known creep rate versus stress relation is then used to solve a specific problem.
Response of a Nonlinear String to Random Loading
Authors: Caughey T. K.
Published: June 2021

This paper considers the response of a nonlinear string to random excitation. It is shown that, owing to the additional stress induced by the stretching of the string, the mean squared deflection at every point is smaller than that for the equivalent linear string.
Vibration of Beam-Mass Systems With Time-Dependent Boundary Conditions
Authors: Yen T. C. , Kao S.
Published: June 2021

Vibration problems of beams with time-dependent boundary conditions are solved by the method of Laplace transforms. The problems treated include the simply supported, cantilevered, and fixed beams carrying a single arbitrarily placed mass; two equal masses symmetrically placed on a simply supported or fixed-end beam and a beam carrying a mass at the center and two equal masses at tips, striking a spring.
On the Instability and Folding Deformation of a Layered Viscoelastic Medium in Compression
Authors: Biot M. A.
Published: June 2021

When a layer of material embedded in an infinite medium is subject to a compression parallel with the layer an instability tends to develop which manifests itself in the folding of the layer. This phenomenon is examined here for the general case where the layer and the surrounding medium are both viscoelastic. This problem which was examined in preliminary form in an earlier publication [6] is treated here with particular attention to the effect of interfacial adherence of the layer and the medium, and to an evaluation of the amplitude of the folding. In general there is a lower and upper-critical value of the compressive load between which folding occurs with a finite rate of deformation. There appears also a dominant wave length, for which the rate of folding is maximum under a given load. The dominant wave length may or may not depend on the load. The effect of interfacial adherence while not negligible is not generally significant. The rate of folding increases very rapidly beyond a certain value of the viscosity ratio of the two media. A brief discussion is also included of the thermodynamic implications of incremental stress-strain relations in prestressed media.
The Stress Distribution in a Semi-Infinite Strip Subjected to a Concentrated Load
Authors: Theocaris P. S.
Published: June 2021

A solution is presented for the stress distribution in a semi-infinite strip subjected to an axial concentrated compressive load. The problem is solved by using the function z = f(w) defining the Schwarz-Christoffel transformation. All the boundary conditions are satisfied except along the two longitudinal edges of the strip. Normal stresses along these boundaries are present which are eliminated by applying the minimum-strain-energy principle at a part of the strip. The stress components are calculated along all the boundaries and the axis of symmetry, as well as along three transverse sections in the neighborhood of the applied load. The theoretical results are compared with experimental results obtained by using photoelasticity and the electrical analogy method for the tracing of isostatics.
Postbuckling Behavior of Rectangular Plates With Small Initial Curvature Loaded in Edge Compression
Authors: Yamaki Noboru
Published: June 2021

The solution of Marguerre’s fundamental equations for large deflections of thin plates with slight initial curvature is presented for the case of a rectangular plate subjected to edge compression. The problem is solved under eight different boundary conditions, combining two kinds of loading conditions and four kinds of supporting conditions. Numerical solutions are obtained for square plates with and without initial deflection, and the connections of deflection, edge shortening, and effective width of the plate with applied loads are clarified. The solutions here obtained include as special cases those investigated by Levy and Coan.
The Stress Function of a Radial Strain
Authors: Goded F.
Published: June 2021

A stress function which permits the study of radial strain and, in particular, the manner of determining this stress function in a given cone, are derived in this paper.
The Determination of Safe Loads of Beams Subjected to Combined Twisting and Biaxial Bending Moments
Authors: Hodge P. G. , Sankaranarayanan R.
Published: June 2021

Using the lower-bound theorem of limit analysis, a yield criterion is obtained in terms of the stress resultants for a beam, subjected to combined twisting and biaxial bending moments. Based on a piecewise linear approximate yield condition, the “collapse load” is determined for a right-angle bent, subjected to a load in an arbitrary direction applied to the mid-point of one leg. Such a collapse load, which is a “safe load” for the beam, is plotted as a function of a suitable parameter.
Slow Rotatory Motion of a Circular Disk About One of Its Diameters in a Viscous Fluid
Authors: Kanwal R. P.
Published: June 2021

An analytic solution is presented for the case when a rigid circular plate is made to rotate about a diameter in its plane, in an infinite mass of viscous fluid. Formulas are derived for the velocity components, pressure, and the couple experienced by the disk.
On Inertia Effects in a Transient Thermoelastic Problem
Authors: Sternberg Eli , Chakravorty J. G.
Published: June 2021

This paper is concerned with the dynamic treatment of a transient thermoelastic problem for a semi-infinite medium which is constrained against transverse displacements and is exposed to a uniform time-dependent heating (or cooling) of its entire plane boundary. The stress distribution appropriate to this problem, in the event that the surface temperature is a step-function of time, was previously established by Danilovskaya [1] and by Mura [2]. In the present investigation the accompanying displacements are determined in closed form. In addition, an exact closed solution, in terms of error functions, is obtained for the case in which the time-dependence of the given surface temperature is of the ramp-type. The ensuing field of thermal stress is compared with the corresponding quasi-static stress distribution, with a view toward a quantitative assessment of the accompanying inertia effects as influenced by the rate at which the temperature of the boundary is altered. The results indicate that the conclusions reached in [1] and [2] are in need of essential modification once the assumption of an instantaneous change of the surface temperature is abandoned.
Production of Rotation in a Confined Liquid Through Translational Motion of the Boundaries
Authors: Berlot R. R.
Published: June 2021

The motion of a fluid contained in a cylindrical tank driven laterally to its axis is analyzed in terms of a combination of surface waves and a two-dimensional combined vortex. Nonlinearities are introduced by analogy with the motions of a set of spherical pendulums. The results of theory and experiment agree within the limits of experimental error and the approximations of the theory.
Nonlinear Creep Deformations of Columns of Rectangular Cross Section
Authors: Bleich H. H. , Dillon O. W.
Published: June 2021

Creep deformations of columns of rectangular cross section are studied for the case of materials following the nonlinear law ϵ̇ = (1/E) σ̇ + λσk. The essential point of the paper is the following: The time rate of the curvature κ̇ of an element of a bar loaded by a constant force P and an increasing bending moment M(t) has bounds, which depend on P and on the instantaneous values of M and Ṁ, but not on the history of M. In combination with the collocation method, this permits the formulation of ordinary differential equations for upper and lower bounds on the deformations. Closed solutions for the critical time are obtained for one bound, while the other requires numerical integration. The bounds which are a function of the initial eccentricity are reasonably close and are presented in tables and graphs. By qualitative reasoning it is further shown that the location of the actual critical time with respect to the two bounds is governed by the ratio of the column load P and the nominal Euler buckling load PE of the column if it were elastic.
Forced Vibrations of a Circular Plate
Authors: Reismann Herbert
Published: June 2021

A solution is presented for the response of a clamped, circular plate to the action of an arbitrarily placed, harmonically oscillating, transverse, concentrated force. The method may be extended to a variety of loading and boundary conditions and can also be applied to ring-shaped plates.
The Frequency of Flexural Vibration of Rectangular Orthotropic Plates With Clamped or Supported Edges
Authors: Hearmon R. F. S.
Published: June 2021

The Rayleigh method, using characteristic beam functions appropriate to the boundary conditions, is applied to derive closed formulas for the frequencies of vibration of orthotropic plates under any combination of clamped or supported edges.
Viscous Flow Through Tubes of Multiply Connected Cross Sections
Authors: Gaydon F. A. , Nuttall H.
Published: June 2021

A new method is proposed for estimating the volume flow of a viscous incompressible fluid through a cylindrical tube of multiply connected cross section. The method brackets the magnitude of the volume flow between upper and lower bounds. The essential feature of the method is that the calculation of both upper and lower bounds is based upon the same approximating function for the velocity distribution, thus avoiding the usual approach to a lower bound via the Rayleigh-Ritz method. For multiply connected cross sections of the form discussed, a Rayleigh-Ritz solution of sufficient accuracy becomes extremely laborious. Efforts to solve the problem by relaxation methods are also rendered difficult by the presence of high-velocity gradients in the vicinity of an internal boundary, particularly when this is a small circle. In contrast to these methods the one presented achieves the result with considerably less labor; moreover, the method is directly applicable to simply connected cross sections with many-sided boundaries.
Developments in the Application of the Grid Method to Dynamic Problems
Authors: Durelli A. J. , Dally J. W. , Riley W. F.
Published: June 2021

The objective of the research reported in this paper was to develop the grid method further for use in dynamic-stress studies. A rubber-thread grid network in a low-modulus model material (a urethane rubber known as Hysol 8705) was used in conjunction with a microflash light source to record grid distortions and photoelastic fringe patterns in a model subjected to dynamic-loading conditions. By considering a strut subjected to axial impact it was possible to establish that the static and dynamic values of Poisson’s ratio were identical, and the strain-fringe value of the material varied with strain rate. In addition, stresses in the axial and transverse directions were determined along the center line of the strut. Finally, the methods established were applied to the problem of a circular disk subjected to diametrical impact and both principal stresses were determined along a vertical diameter at one instant during impact.
Transient Analysis of Stress-Wave Penetration in Plates
Authors: Davids Norman
Published: June 2021

This paper carries out an analysis of the propagation of a transient stress pulse concentrated at a point on the boundary of a plate whose thickness is of the order of a wave length. It is based on an expansion method used by Caignard in geophysical-layer problems which obviates the contour-integration difficulties and whose terms represent successively reflected waves of increasing time delay. From the general formulas obtained in this paper for an arbitrary forcing function, the stress versus time distribution along the axis of a 1-in-thick aluminum plate is obtained for a 5-microsec exponentially decaying pressure pulse. Inside the plate it is found there is a compressed zone which is relieved by a negative front traveling with the distortional wave velocity. When this interferes with a certain reflected negative front, the stress reverses in sign. A comparison of the location of this reversal is made with those based on plane-wave assumptions. Limiting cases are discussed.
Transverse Flexure of a Semi-Infinite Thin Plate Containing an Infinite Row of Circular Holes
Authors: Tamate O.
Published: June 2021

The problem of finding stress resultants in a semi-infinite plate under plain bending and containing an infinite row of equal and equally spaced circular holes is discussed on the basis of the Poisson-Kirchhoff theory of thin plates. A method of perturbation is adopted for the determination of parametric coefficients included in the solution. The maximum bending moments occurring on the rim of the hole across the minimum section are calculated for several cases and shown in graphs, from which the mutual interference of adjacent boundaries will be informed.
Large-Eddy Simulation Investigation of Modified Rib Shapes on Heat Transfer in a Ribbed Duct
Authors: Sreekesh K. , Tafti D. K. , Vengadesan S.
Published: June 2021

Internal cooling of the gas turbine blade is critical for the durability of the blade material. One of the ways to accomplish this is by passing coolant through serpentine passages roughened with surface elements to enhance the heat transfer. In the present study, the traditional square rib (SQ-rib) placed normal to the flow direction is modified to a backward-facing step rib (BS-rib) and a forward-facing step rib (FS-rib). Large-eddy simulation (LES) is carried out for a square duct at Reb = 20000. Results show that the modified rib shapes result in substantial increase in heat transfer over the square rib with only a marginal increase in flow losses. The BS-rib shape produces the highest heat transfer augmentation followed by the FS-rib. The overall heat transfer augmentation for the BS-rib and FS-rib is 18% and 10% larger than the SQ-rib, respectively. Thermal-hydraulic performance is enhanced by 15%.
Assessment of Spray and Pool Scrubbing Efficiencies for Means of Mitigation Against Aerosol Dispersion in the Context of Fuel Debris Retrieval at Fukushima Daiichi: Part II
Authors: Porcheron Emmanuel , Leblois Yohan , Gelain Thomas , Chagnot Christophe , Journeau Christophe , Roulet Damien
Published: June 2021

The general context of this paper is an evaluation of strategies that can be used to mitigate aerosol dispersion during fuel debris or corium retrieval in damaged Fukushima Daiichi reactors. Knowledge of the aerosol source terms released during fuel debris retrieval operations is one of the key factors for assessing aerosol dispersion leading to the potential dissemination of radionuclides into the environment. Our approach is to couple experimental results from integral tests obtained during laser cutting experiments, well-controlled analytical tests with separated effects performed in a dedicated facility to reproduce two-phase flow such as flows representative of pool scrubbing and spray scrubbing conditions, and numerical simulations. Integral tests provide relevant information on the airborne particle release fraction during laser cutting for underwater conditions at different water depths, such as the particle concentration and particle size distribution. However, the detailed characterization of two-phase flows, such as the size and velocity of gas bubble and water droplets generated by spray systems, is not possible during laser cutting integral tests. Therefore, a more analytical approach is necessary to obtain detailed information on two-phase flow, composed of bubbles in water, inducing pool scrubbing phenomenon, and droplets in gas generated by spray scrubbing systems used for mitigating dust dispersion, which are essential to the physical mechanisms of both processes and enable their respective efficiencies to be evaluated. The main objectives of this work were to develop models and ensure their validation based on experimental approach for predicting the pool scrubbing and spray scrubbing efficiencies in the context of fuel debris removal at Fukushima Daiichi.
Non-Dimensional Parameters for Comparing Conventional and Counter-Rotating Turbomachines
Authors: Waldren J. J. , Clark C. J. , Grimshaw S. D. , Pullan G.
Published: June 2021

Counter-rotating turbomachines have the potential to be high efficiency, high power density devices. Comparisons between conventional and counter-rotating turbomachines in the literature make multiple and often contradicting conclusions about their relative performance. By adopting appropriate non-dimensional parameters, based on relative blade speed, the design space of conventional machines can be extended to include those with counter-rotation. This allows engineers familiar with conventional turbomachinery to transfer their experience to counter-rotating machines. By matching appropriate non-dimensional parameters, the loss mechanisms directly affected by counter-rotation can be determined. A series of computational studies are performed to investigate the relative performance of conventional and counter-rotating turbines (CRTs) with the same non-dimensional design parameters. Each study targets a specific loss source, highlighting which phenomena are directly due to counter-rotation and which are solely due to blade design. The studies range from two-dimensional blade sections to three-dimensional finite radius stages. It is shown that, at hub-to-tip ratios (HTRs) approaching unity, with matched non-dimensional design parameters, the stage efficiency and work output are identical for both types of machines. However, a CRT in the study is shown to have an efficiency advantage over a conventional machine of up to 0.35 percentage points for a HTR of 0.65. This is due to differences in absolute velocity producing different spanwise blade designs.
Parametric acoustic array lensed by a gradient-index phononic crystal
Authors: Červenka Milan , Bednařík Michal
Published: June 2021

This work presents a theoretical study of a parametric transmitter employing a small ultrasonic transducer and an acoustic lens for the collimation of the non-directional primary ultrasonic waves into a highly-directional beam. The acoustic lens is represented by a gradient-index phononic crystal (GRIN PC) composed of an array of toroidal scatterers. Parameters of the GRIN PC lens are determined employing an optimization procedure that maximizes the minimum value of the primary-wave amplitude over a wide frequency range at a distant point in front of the transducer-lens system. The Westervelt equation is used as a wave equation taking into account diffraction, nonlinearity, and thermoviscous attenuation. The wave equation is solved numerically in the quasi-linear approximation in the frequency domain employing the finite element method. The numerical results show that employing a simple GRIN PC lens, a highly-directional low-frequency beam can be parametrically radiated from a small ultrasonic transducer.
Challenges, Achievements, and Uncertainties: The Philosophy of Sport Since the 1980s
Authors: Kretchmar R. Scott , Torres Cesar R.
Published: June 2021

The philosophy of sport has flourished in some ways and struggled in others since the publication of George Brooks’s anthologyPerspectives on the Academic Discipline of Physical Education: A Tribute to G. Lawrence Rarickin 1981. In this article, the authors trace challenges faced by the philosophy of sport, discuss trends and hot topics, analyze opportunities for integrations with other subdisciplines, and speculate on the current issues in and the future of the philosophy of sport. While they conclude that the philosophy of sport’s prospect within kinesiology is uncertain and that it has work to do, they also conclude that this subdiscipline is uniquely positioned to provide kinesiology with the clarity and unity of purpose it needs.
Notch1 switches progenitor competence in inducing medulloblastoma
Authors: Ballabio Claudio , Gianesello Matteo , Lago Chiara , Okonechnikov Konstantin , Anderle Marica , Aiello Giuseppe , Antonica Francesco , Zhang Tingting , Gianno Francesca , Giangaspero Felice , Hassan Bassem A. , Pfister Stefan M. , Tiberi Luca
Published: June 2021

Notch1 pathway activation is required for group 3 medulloblastoma initiation.
One for all: Universal material model based on minimal state-space neural networks
Authors: Bonatti Colin , Mohr Dirk
Published: June 2021

Machine learning model with optimally few state variables predicts 3D stress-strain response for a vast spectrum of materials.
Exploiting radiative cooling for uninterrupted 24-hour water harvesting from the atmosphere
Authors: Haechler Iwan , Park Hyunchul , Schnoering Gabriel , Gulich Tobias , Rohner Mathieu , Tripathy Abinash , Milionis Athanasios , Schutzius Thomas M. , Poulikakos Dimos
Published: June 2021

This work presents a continuously operating (24-hour), energy-neutral, radiative cooling system, to harvest water from the air.
Genomic evidence for the Chinese mountain cat as a wildcat conspecific (
Felis silvestris bieti
) and its introgression to domestic cats
Authors: Yu He , Xing Yue-Ting , Meng Hao , He Bing , Li Wen-Jing , Qi Xin-Zhang , Zhao Jian-You , Zhuang Yan , Xu Xiao , Yamaguchi Nobuyuki , Driscoll Carlos A. , O’Brien Stephen J. , Luo Shu-Jin
Published: June 2021

Genomic evidence reveals the Chinese mountain cat as a wildcat subspecies with introgression to sympatric domestic cats.
Gradient bimetallic ion–based hydrogels for tissue microstructure reconstruction of tendon-to-bone insertion
Authors: Yang Renhao , Li Gen , Zhuang Chengyu , Yu Pei , Ye Tingjun , Zhang Yin , Shang Peiyang , Huang Jingjing , Cai Ming , Wang Lei , Cui Wenguo , Deng Lianfu
Published: June 2021

Novel gradient bimetallic hydrogel promotes tendon-to-bone interface reconstruction by synchronous regeneration.
Reactivation of the tumor suppressor PTEN by mRNA nanoparticles enhances antitumor immunity in preclinical models
Authors: Lin Yao-Xin , Wang Yi , Ding Jianxun , Jiang Aiping , Wang Jie , Yu Mian , Blake Sara , Liu Shuaishuai , Bieberich Charles J. , Farokhzad Omid C. , Mei Lin , Wang Hao , Shi Jinjun
Published: June 2021

The restoration of tumor suppressor PTEN by synthetic mRNA nanoparticles sensitizes
Pten
-null or mutated tumors to immune checkpoint blockade therapy.
A Baeyer-Villiger Monooxygenase Gene Involved in the Synthesis of Lysergic Acid Amides Affects the Interaction of the Fungus Metarhizium brunneum with Insects
Authors: Steen Chey R. , Sampson Jessi K. , Panaccione Daniel G.
Published: June 2021

Fungi in the genus
Metarhizium
are important plant root symbionts and insect pathogens. They are formulated commercially to protect plants from insect pests.
Metagenome-Assembled Genomes of Novel Taxa from an Acid Mine Drainage Environment
Authors: Grettenberger Christen L. , Hamilton Trinity L.
Published: June 2021

Bioremediating acid mine drainage requires understanding how microbial communities influence geochemical cycling of iron and sulfur and biologically important elements such as carbon and nitrogen. Research in this area has provided an abundance of 16S rRNA gene amplicon data.
Phyllosphere Community Assembly and Response to Drought Stress on Common Tropical and Temperate Forage Grasses
Authors: Bechtold Emily K. , Ryan Stephanie , Moughan Sarah E. , Ranjan Ravi , Nüsslein Klaus
Published: June 2021

Globally important grassland ecosystems are at risk of degradation due to poor management practices compounded by predicted increases in severity and duration of drought over the next century. Finding new ways to support grassland productivity is critical to maintaining their ecological and agricultural benefits.
Glyceraldehyde-3-Phosphate Dehydrogenase Restricted in Cytoplasmic Location by Viral GP5 Facilitates Porcine Reproductive and Respiratory Syndrome Virus Replication via Its Glycolytic Activity
Authors: Liu Xuewei , Liu Xing , Bai Juan , Gao Yanni , Song Zhongbao , Nauwynck Hans , Wang Xianwei , Yang Yuanqi , Jiang Ping
Published: June 2021

PRRSV poses a severe economic threat to the pig industry. PRRSV GP5, the major viral envelope protein, plays an important role in viral infection, pathogenicity, and immunity.
Functional Heterogeneity of Mammalian IFITM Proteins against HIV-1
Authors: Marziali Federico , Delpeuch Mathilde , Kumar Anuj , Appourchaux Romain , Dufloo Jérémy , Tartour Kevin , Etienne Lucie , Cimarelli Andrea
Published: June 2021

IFITMs are broad viral inhibitors capable of interfering with both early and late phases of the replicative cycle of many different viruses. By comparing 21 IFITM proteins issued from different animal species for their ability to inhibit HIV-1, we have identified several that exhibit either enhanced or impaired antiviral behavior.
Potent Human Single-Domain Antibodies Specific for a Novel Prefusion Epitope of Respiratory Syncytial Virus F Glycoprotein
Authors: Xun Guangjin , Song Xingpan , Hu Jie , Zhang Haiwei , Liu Lan , Zhang Zhe , Gong Rui
Published: June 2021

Because respiratory syncytial virus (RSV) can cause serious respiratory disease in immunodeficient groups, including infants and seniors, the development of vaccines and therapeutic drugs, such as neutralizing antibodies, is urgently needed. Compared to the conventional full-length antibody, a single-domain antibody (sdAb) has been demonstrated to be efficient for respiratory diseases when administered by inhalation, thereby potentially introducing a kind of novel therapeutic agent in the market.
A Novel Strain-Specific Neutralizing Epitope on Glycoprotein H of Human Cytomegalovirus
Authors: Thomas Marco , Kropff Barbara , Schneider Andrea , Winkler Thomas H. , Görzer Irene , Sticht Heinrich , Britt William J. , Mach Michael , Reuter Nina
Published: June 2021

HCMV infections are life threatening to people with compromised or immature immune systems. Understanding the antiviral antibody repertoire induced during HCMV infection is a necessary prerequisite to define protective antibody responses.
Identification and Characterization of Defective Viral Genomes in Ebola Virus-Infected Rhesus Macaques
Authors: Johnson Rebecca I. , Boczkowska Beata , Alfson Kendra , Weary Taylor , Menzie Heather , Delgado Jenny , Rodriguez Gloria , Carrion Ricardo , Griffiths Anthony
Published: June 2021

The study of filovirus pathogenesis is critical for understanding the consequences of infection and for the development of strategies to ameliorate future outbreaks. Defective viral genomes (DVGs) have been detected during EBOV infections
in vitro
; however, their presence in
in vivo
infections remains unknown.
Universal Influenza Virus Neuraminidase Vaccine Elicits Protective Immune Responses against Human Seasonal and Pre-pandemic Strains
Authors: Skarlupka Amanda L. , Bebin-Blackwell Anne-Gaelle , Sumner Spencer F. , Ross Ted M.
Published: June 2021

The development and distribution of a universal influenza vaccine would alleviate global economic and public health stress from annual influenza virus outbreaks. The influenza virus NA vaccine antigen allows for protection from multiple HA subtypes and virus host origins, but it has not been the focus of vaccine development.
SARS-CoV-2 Spike Protein Induces Paracrine Senescence and Leukocyte Adhesion in Endothelial Cells
Authors: Meyer Keith , Patra Tapas , Vijayamahantesh  , Ray Ranjit
Published: June 2021

The present study was aimed at examining the underlying mechanism of extrapulmonary manifestations of SARS-CoV-2 spike protein-associated pathogenesis, with the notion that infection of the pulmonary epithelium can lead to mediators that drive endothelial dysfunction. We utilized SARS-CoV-2 spike protein expression in cultured human hepatocytes (Huh7.5) and pneumocytes (A549) to generate conditioned culture medium (CM).
Chemical Condensation Wave Initiating Oxygen-Free Combustion and Detonation
Authors: Emelianov A. V. , Eremin A. V. , Fortov V. E.
Published: June 2021

It is well known that the propagation of traditional combustion and detonation waves was determined by the branched chain reactions discovered by Academician N.N. Semenov. This article discusses a new type of detonation waves initiated by chemical condensation processes. Chemical condensation waves arise as a result of the heat released during the explosive condensation of a highly supersaturated carbon vapor formed as a result of the dissociation of the initial carbon-containing molecules behind the front of the initiating shock wave. Unlike traditional combustion and detonation waves, the mechanism of chemical condensation does not include branched chain reactions; nevertheless, the laws of propagation of detonation waves of condensation are clearly described by the Zel’dovich–Neumann–Döring theory.