scholarly journals GROWTH DISTRIBUTION IN THE LIGHT-GROWTH RESPONSE OF PHYCOMYCES

1959 ◽  
Vol 42 (4) ◽  
pp. 697-702 ◽  
Author(s):  
Edward S. Castle
Keyword(s):  
Spatial Distribution ◽  
Steady State ◽  
Growth Response ◽  
Spatial Separation ◽  
Growth Zone ◽  
Starch Grains ◽  
Growth Distribution

Elongation of sporangiophores marked with numerous starch grains was photographically recorded in the steady state and during the light-growth response when the rate is more than doubled. From these records the spatial distribution of growth within the cell's growth zone was derived. Stimulation by a single saturating flash of light speeds growth proportionally in all parts of the growing zone, maintaining the same pattern of growth distribution as in the steady state. This finding implies that light is absorbed and acts locally throughout the length of the cell's growth zone. Cohen and Delbrück's proposal of a partial spatial separation of light reception and growth is discussed.

scholarly journals Drought Induces Distinct Growth Response, Protection, and Recovery Mechanisms in the Maize Leaf Growth Zone

2015 ◽  
Vol 169 (2) ◽  
pp. 1382-1396 ◽  
Author(s):  
Viktoriya Avramova ◽  
Hamada AbdElgawad ◽  
Zhengfeng Zhang ◽  
Bartosz Fotschki ◽  
Romina Casadevall ◽  
...  
Keyword(s):  
Growth Response ◽  
Leaf Growth ◽  
Growth Zone ◽  
Maize Leaf ◽  
Recovery Mechanisms

scholarly journals Asymptotic Methods in the Nonlinear Mean-field Dynamo

1991 ◽  
Vol 130 ◽  
pp. 135-139
Author(s):  
D.D. Sokoloff ◽  
A. Shukurov ◽  
A.A. Ruzmaikin
Keyword(s):  
Magnetic Field ◽  
Spatial Distribution ◽  
Steady State ◽  
Main Part ◽  
Asymptotic Methods ◽  
Mean Field ◽  
Coriolis Forces ◽  
The Mean ◽  
The Magnetic Field ◽  
Mean Field Dynamo

AbstractWe discuss the methods and results of analysis of nonlinear mean-field dynamo models based on α-quenching in two asymptotic regimes, namely for weakly and highly supercritical excitation. In the former case the spatial distribution of the steady-state magnetic field is close to that given by the neutrally stable eigenfunction of the corresponding kinematic dynamo. In the latter case the magnetic field distribution within the main part of the dynamo volume is presumably determined by the balance between the Lorentz and Coriolis forces while near the boundaries boundary layers arise in which the field adjusts itself to the boundary conditions. The asymptotic behaviour of the highly supercritical αω-dynamos is sensitive to the particular form of dependence of the mean helicity on magnetic field while α2-dynamos are less sensitive to this dependence.

Notizen: Zur Beteiligung des Triplettzustandes im Kristall an der sensibilisierten Erzeugung von Defektelektronen in aromatischen Kohlenwasserstoffen

1972 ◽  
Vol 27 (2) ◽  
pp. 368-369
Author(s):  
F. Willig
Keyword(s):  
Spatial Distribution ◽  
Steady State ◽  
Light Intensity ◽  
Delayed Fluorescence ◽  
Anthracene Crystal ◽  
Hole Generation ◽  
Triplet Excitons

AbstractThe steady-state spatial distribution has been calculated for triplet excitons generated at the surface of an anthracene crystal. The dependence on the light intensity has been discussed for a hole generation and delayed fluorescence, due to the triplet excitons.

Spatial Distribution Prediction of Steady-State Sound Field With the Ray-Tracing Method

2008 ◽  
Vol 130 (6) ◽  
Author(s):  
Zhong-Jin Jiang ◽  
Tie-Jun Cui
Keyword(s):  
Spatial Distribution ◽  
Steady State ◽  
Ray Tracing ◽  
Three Dimensional ◽  
Sound Field ◽  
Energy Matrix ◽  
Sound Energy ◽  
Sound Fields ◽  
Level Ii ◽  
Level I

A novel two-level space volume partition (SVP) algorithm based on the ray-tracing technique is proposed to predict the spatial distribution of the steady-state sound field. The sound space is subdivided into voxels in two levels. The voxels of the level-I are of greater size and comparable to the space walls, and the ray-wall intersection points are calculated based on this level of voxels. Then each level-I voxel is hierarchically subdivided into small voxels of level-II, the size of which is determined according to the needed solution in the sound field description. The sound field spatial distribution is predicted based on this level of voxels. A three-dimensional energy matrix is set up to memorize the spatial distribution of sound energy. The numbers of the row, column, and layer of the energy matrix are equal to those of the level-II voxels, namely, each element in the energy matrix corresponds to a level-II voxel. When a sound ray enters a voxel, its sound energy is calculated and recorded in the corresponding element of the energy matrix. When all the sound rays have been traced over, the sound energy spatial distribution in the sound space has been established in the energy matrix. The sound pressure level (SPL) in a certain plane or along a certain line can be calculated and imaged directly from the energy matrix. The novel two-level SVP algorithm can finish the simulation more efficiently than the traditional SVP algorithm. Experiments were performed to measure the SPL in steady-state sound fields, and the results were consistent with the predicted results.

scholarly journals Phototropism, Adaptation, and the Light-Growth Response of Phycomyces

1961 ◽  
Vol 45 (1) ◽  
pp. 39-46 ◽  
Author(s):  
Edward S. Castle
Keyword(s):  
Steady State ◽  
Growth Response ◽  
Model System ◽  
Radiant Flux ◽  
Growth Speed ◽  
Growth Responses ◽  
State Process ◽  
Steady State Process

Phototropic bending can be initiated without the transient changes in growth speed that characterize a light-growth response. The conditions required are a change from a symmetric to an asymmetric illumination pattern while the cell receives a constant radiant flux. Phototropism is thus basically a steady state process. It cannot be founded on differential light-growth responses as in Blaauw's theory. A possible model system for the unequal partition of growth during steady bending is discussed. The fact that light-growth responses show adaptation while phototropic bending does not follows from the different natures of the two responses.

A two-pinhole technique to determine distribution profiles of relative elemental growth rates in the growth zone of grass leaves

2000 ◽  
Vol 27 (12) ◽  
pp. 1187
Author(s):  
Urs Schmidhalter ◽  
Yuncai Hu
Keyword(s):  
Spatial Distribution ◽  
Growth Rates ◽  
Growth Zone ◽  
Elongation Rate ◽  
New Technique ◽  
Leaf Elongation ◽  
Distribution Profile

A new modified pricking technique, a two-pinhole method, was designed to determine the spatial distribution of leaf elongation of grasses. This new technique makes it possible to obtain the distribution profiles of relative elemental growth rates in the growth zone, to evaluate the effect of pricking on the distribution profile of leaf elongation in the growth zone and to decrease the reduction in the elongation rate of grass leaves due to pricking.

scholarly journals Constraining dynamical models with observational data

2013 ◽  
Vol 9 (S298) ◽  
pp. 185-194
Author(s):  
Jo Bovy
Keyword(s):  
Spatial Distribution ◽  
Steady State ◽  
Milky Way ◽  
Velocity Curve ◽  
Matter Distribution ◽  
Dynamical Models ◽  
Dynamical Modeling ◽  
Optimal Analysis ◽  
Circular Velocity ◽  
Multiple Orders

AbstractThe spatial distribution and kinematics of stars in the Milky Way are linked through the gravitational potential. Observations of the positions and velocities of stars can therefore be used to measure the mass distribution of the Milky Way. I review steady-state dynamical modeling approaches and illustrate their use in constraining the local matter distribution and the circular velocity curve from the kinematics of stellar tracers. In a few years, Gaia will increase the number of precise positions and velocities by multiple orders of magnitude. I describe some of the dynamical analyses that will be possible with the Gaia data and discuss some promising avenues for the optimal analysis of dynamical data.

scholarly journals Speech Recognition and Temporal Processing in Middle-Aged Women

2009 ◽  
Vol 20 (04) ◽  
pp. 264-271 ◽  
Author(s):  
Karen S. Helfer ◽  
Megan Vargo
Keyword(s):  
Steady State ◽  
Temporal Processing ◽  
Repeated Measures ◽  
Pure Tone ◽  
Spatial Separation ◽  
Strong Relationship ◽  
Speech Understanding ◽  
Middle Aged ◽  
Aged Subjects ◽  
Competing Speech

Purpose: This study was designed to examine speech understanding ability and temporal processing in middle-aged women with normal or near-normal pure-tone thresholds. Research Design: Speech understanding, temporal processing ability, and self-assessed hearing were measured in groups of younger and middle-aged females. Study Sample: Participants were younger and middle-aged females (n = 12 per group) with normal hearing through 4000 Hz bilaterally. Subjects were drawn from nonclinical populations. Data Collection and Analysis: Speech understanding was measured in the presence of steady-state noise and competing speech, with and without perceived spatial separation of the target speech and masker. The Gaps-In-Noise (GIN) test (Musiek et al, 2005) was used to assess temporal resolution ability. In addition, subjects completed a questionnaire with several items from the Speech, Spatial, and Qualities of Hearing Scale (Gatehouse and Noble, 2004) to gauge their subjective ability to understand speech in complex listening situations. Data were analyzed via repeated-measures ANOVA and Pearson r correlations. Results: Results showed that the performance of the middle-aged subjects was significantly poorer than that of the younger participants in the presence of a spatially coincident speech masker. Although performance in this listening condition was unrelated to pure-tone thresholds, it was strongly correlated with scores on the GIN test. Speech understanding performance in the presence of a steady-state masker was related to high-frequency pure-tone thresholds. Conclusions: These results suggest that some middle-aged women with little or no pure-tone hearing loss experience listening difficulty in complex environments. Results also suggest a strong relationship between temporal processing and speech understanding in certain competing speech situations.

scholarly journals Effective interactions mediated between two permeable disks in an active fluid

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Mahmoud Sebtosheikh ◽  
Ali Naji
Keyword(s):  
Spatial Distribution ◽  
Steady State ◽  
Phase Diagrams ◽  
Effective Interaction ◽  
Two Dimensions ◽  
Effective Interactions ◽  
Active Fluid ◽  
Brownian Particles ◽  
Exterior Regions ◽  
Pass Through

Abstract We study steady-state properties of a bath of active Brownian particles (ABPs) in two dimensions in the presence of two fixed, permeable (hollow) disklike inclusions, whose interior and exterior regions can exhibit mismatching motility (self-propulsion) strengths for the ABPs. We show that such a discontinuous motility field strongly affects spatial distribution of ABPs and thus also the effective interaction mediated between the inclusions through the active bath. Such net interactions arise from soft interfacial repulsions between ABPs that sterically interact with and/or pass through permeable membranes assumed to enclose the inclusions. Both regimes of repulsion and attractive (albeit with different mechanisms) are reported and summarized in overall phase diagrams.

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