The self-thinning process in mangrove Kandelia obovata stands

Consideration is given to the production of biomass in three of the possible growth phases that may be experienced by plants at various spacings in stand monocultures. The amount of radiant energy available for this is related to canopy surface area, volume, and slenderness, and the efficiency with which the operation is performed. The unified non-dimensional formulae established describe normal natural growth, growth with plastic deformation, and growth subject to the self-thinning process, which occurs when individuals are packed too closely together. The formulae define growth surfaces for the life-lines followed by individual plants, and for the rounding and smoothing of these lines that occurs, at the otherwise sharply defined growth phase boundaries, as a result of the statistical uncertainties in specifying plant dimensions and numbers in spacetime. The results provide an explanation of features of the self-thinning process and the values of the constants and parameters associated with approximate power law descriptions of the phase boundary on which it takes place. A quasi-static analysis of growth and thinning mechanisms indicates one-sided competition coexistence conditions for plants in distributions with uniformly augmented and diminished biomass, and the boundaries separating and distinguishing diminished biomass states from which recovery to further growth is, or is not, possible. Because of the dependence of events in the growth process on canopy shape and volume a preliminary classification of suitable geometric forms is given, together with formulae for evaluating the required quantities, for several cases of interest.

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Plant mortality varies with arbuscular mycorrhizal fungal species identities in a self-thinning population

Biology Letters ◽

10.1098/rsbl.2010.1040 ◽

2010 ◽

Vol 7 (3) ◽

pp. 472-474 ◽

Cited By ~ 8

Author(s):

Qian Zhang ◽

Jianjun Tang ◽

Xin Chen

Keyword(s):

Plant Growth ◽

Host Plant ◽

Arbuscular Mycorrhizal ◽

Fungal Species ◽

The Self ◽

Plant Mortality ◽

Microcosm Experiment ◽

Plant Populations ◽

Arbuscular Mycorrhizal Fungal ◽

Thinning Process

Because arbuscular mycorrhizal fungal (AMF) species differ in stimulating the growth of particular host plant species, AMF species may vary in their effects on plant intra-specific competition and the self-thinning process. We tested this hypothesis using a microcosm experiment with Medicago sativa L. as a model plant population and four AMF species. Our results showed that the AMF species Glomus diaphanum stimulated host plant growth more than the other three AMF species did when the plants were grown individually. Glomus diaphanum also induced the highest rate of mortality in the self-thinning plant populations. We also found a positive correlation between mortality and growth response to colonization. Our results demonstrate that AMF species can affect plant mortality and the self-thinning process by affecting plant growth differently.

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Self-thinning process, dynamics of aboveground biomass, and stand structure in overcrowded mangrove Kandelia obovata stand

Regional Studies in Marine Science ◽

10.1016/j.rsma.2020.101375 ◽

2020 ◽

Vol 38 ◽

pp. 101375

Author(s):

Mouctar Kamara ◽

Md. Kamruzzaman

Keyword(s):

Aboveground Biomass ◽

Stand Structure ◽

Kandelia Obovata ◽

Process Dynamics ◽

Thinning Process

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Simulation of Self-Thinning Processes in Even-Aged Single Stands

Математическая биология и биоинформатика ◽

10.17537/2016.11.323 ◽

2016 ◽

Vol 11 (2) ◽

pp. 323-335 ◽

Cited By ~ 1

Author(s):

А.Н. Колобов ◽

A.N. Kolobov

Keyword(s):

Quantitative Description ◽

Spatial Location ◽

The Self ◽

Model Data ◽

Site Class ◽

Main Research ◽

Initial Location ◽

Spruce Stands ◽

Competition For Light ◽

Thinning Process

This paper presents the results of modeling and study of the processes of self-thinning of even-aged spruce stands, depending on the initial spatial location of trees and heterogeneity of the population. The main research tool is developed previously individual-based model of spatiotemporal dynamics of the stand. It is shown that for a quantitative description of the self-thinning process must be considered as a heterogeneous composition of the population as well as the initial spatial structure of the stand. Computational experiments for spruce stands second site class showed that a satisfactory correspondence between the real and model data are obtained by random and cluster the initial location of the trees. At the same time to describe the initial heterogeneity of the population structure was sufficient to seven groups of trees of different ages with different probability of dying out as a result of competition for light.

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Problem behavior in autism spectrum disorders: A paradigmatic self-organized perspective of network structures

Behavioral and Brain Sciences ◽

10.1017/s0140525x18001188 ◽

2019 ◽

Vol 42 ◽

Author(s):

Lucio Tonello ◽

Luca Giacobbi ◽

Alberto Pettenon ◽

Alessandro Scuotto ◽

Massimo Cocchi ◽

...

Keyword(s):

Autism Spectrum Disorder ◽

Problem Behaviors ◽

Autism Spectrum ◽

The Self ◽

Network Structures ◽

Self Organized ◽

Critical Equilibrium ◽

Self Organized Criticality ◽

Acute Agitation ◽

Spectrum Disorders

AbstractAutism spectrum disorder (ASD) subjects can present temporary behaviors of acute agitation and aggressiveness, named problem behaviors. They have been shown to be consistent with the self-organized criticality (SOC), a model wherein occasionally occurring “catastrophic events” are necessary in order to maintain a self-organized “critical equilibrium.” The SOC can represent the psychopathology network structures and additionally suggests that they can be considered as self-organized systems.

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The Nature of Rapidly Extracted Phycocyanin from the Blue-Green Alga Plectonema Boryanum

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100065870 ◽

1971 ◽

Vol 29 ◽

pp. 366-367

Author(s):

M. Kessel ◽

R. MacColl

Keyword(s):

Self Assembly ◽

Analytical Ultracentrifugation ◽

Uranyl Acetate ◽

The Self ◽

Major Protein ◽

Subunit Structure ◽

Blue Green Alga ◽

Thin Sections ◽

Blue Green Algae ◽

Cacodylate Buffer

The major protein of the blue-green algae is the biliprotein, C-phycocyanin (Amax = 620 nm), which is presumed to exist in the cell in the form of distinct aggregates called phycobilisomes. The self-assembly of C-phycocyanin from monomer to hexamer has been extensively studied, but the proposed next step in the assembly of a phycobilisome, the formation of 19s subunits, is completely unknown. We have used electron microscopy and analytical ultracentrifugation in combination with a method for rapid and gentle extraction of phycocyanin to study its subunit structure and assembly.To establish the existence of phycobilisomes, cells of P. boryanum in the log phase of growth, growing at a light intensity of 200 foot candles, were fixed in 2% glutaraldehyde in 0.1M cacodylate buffer, pH 7.0, for 3 hours at 4°C. The cells were post-fixed in 1% OsO4 in the same buffer overnight. Material was stained for 1 hour in uranyl acetate (1%), dehydrated and embedded in araldite and examined in thin sections.

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Polishing process effect on the image of dispersed precipitates

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100112646 ◽

1984 ◽

Vol 42 ◽

pp. 534-535

Author(s):

C.T. Hu ◽

C.W. Allen

Keyword(s):

Matrix Material ◽

Specimen Preparation ◽

Second Phase ◽

Precipitate Particle ◽

Polishing Process ◽

Second Phase Particles ◽

The Matrix ◽

Surface Profiles ◽

Thinning Process

One important problem in determination of precipitate particle size is the effect of preferential thinning during TEM specimen preparation. Figure 1a schematically represents the original polydispersed Ni3Al precipitates in the Ni rich matrix. The three possible type surface profiles of TEM specimens, which result after electrolytic thinning process are illustrated in Figure 1b. c. & d. These various surface profiles could be produced by using different polishing electrolytes and conditions (i.e. temperature and electric current). The matrix-preferential-etching process causes the matrix material to be attacked much more rapidly than the second phase particles. Figure 1b indicated the result. The nonpreferential and precipitate-preferential-etching results are shown in Figures 1c and 1d respectively.

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Interrelationship of the cellular distribution and secretion of regular structure (RS) protein in Bacillus licheniformis nm 105

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100123969 ◽

1992 ◽

Vol 50 (1) ◽

pp. 712-713

Author(s):

Xiaorong Zhu ◽

Richard McVeigh ◽

Bijan K. Ghosh

Keyword(s):

Alkaline Phosphatase ◽

Bacillus Licheniformis ◽

Self Assembly ◽

Gel Electrophoresis ◽

Culture Supernatant ◽

Regular Structure ◽

The Self ◽

Cellular Distribution ◽

Structural Protein ◽

Laboratory Cultures

A mutant of Bacillus licheniformis 749/C, NM 105 exhibits some notable properties, e.g., arrest of alkaline phosphatase secretion and overexpression and hypersecretion of RS protein. Although RS is known to be widely distributed in many microbes, it is rarely found, with a few exceptions, in laboratory cultures of microorganisms. RS protein is a structural protein and has the unusual properties to form aggregate. This characteristic may have been responsible for the self assembly of RS into regular tetragonal structures. Another uncommon characteristic of RS is that enhanced synthesis and secretion which occurs when the cells cease to grow. Assembled RS protein with a tetragonal structure is not seen inside cells at any stage of cell growth including cells in the stationary phase of growth. Gel electrophoresis of the culture supernatant shows a very large amount of RS protein in the stationary culture of the B. licheniformis. It seems, Therefore, that the RS protein is cotranslationally secreted and self assembled on the envelope surface.

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