Hyperbolic B-Potentials: Properties and Inversion

Spheroids of the green colonial alga Volvox consist of biflagellate Chlamydomonad-like cells embedded in a transparent sheath. The sheath, important as a substance through which metabolic materials, light, and the sexual inducer must pass to and from the cells, has been shown to have an ordered structure (1,2). It is composed of both protein and carbohydrate (3); studies of V. rousseletii indicate an outside layer of sulfated polysaccharides (4).Ultrastructural studies of the sheath material in developmental stages of V. carteri f. weismannia were undertaken employing variations in the standard fixation procedure, ruthenium red, diaminobenzidine, and high voltage electron microscopy. Sheath formation begins after the completion of cell division and inversion of the daughter spheroids. Golgi, rough ER, and plasma membrane are actively involved in phases of sheath synthesis (Fig. 1). Six layers of ultrastructurally differentiated sheath material have been identified.

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Exsolution and inversion in pigeonite from the Whin Sill, Northern England

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100109513 ◽

1978 ◽

Vol 36 (1) ◽

pp. 474-475

Author(s):

P.P.K. Smith

Keyword(s):

High Temperature ◽

Low Temperature ◽

Homogeneous Nucleation ◽

Silicate Mineral ◽

Antiphase Boundaries ◽

Two Phase ◽

Primitive Form ◽

The Core ◽

Nucleation Mechanisms ◽

And Inversion

Grains of pigeonite, a calcium-poor silicate mineral of the pyroxene group, from the Whin Sill dolerite have been ion-thinned and examined by TEM. The pigeonite is strongly zoned chemically from the composition Wo8En64FS28 in the core to Wo13En34FS53 at the rim. Two phase transformations have occurred during the cooling of this pigeonite:- exsolution of augite, a more calcic pyroxene, and inversion of the pigeonite from the high- temperature C face-centred form to the low-temperature primitive form, with the formation of antiphase boundaries (APB's). Different sequences of these exsolution and inversion reactions, together with different nucleation mechanisms of the augite, have created three distinct microstructures depending on the position in the grain.In the core of the grains small platelets of augite about 0.02μm thick have farmed parallel to the (001) plane (Fig. 1). These are thought to have exsolved by homogeneous nucleation. Subsequently the inversion of the pigeonite has led to the creation of APB's.

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Associations between environmental variability and inversion polymorphism of Drosophila subobscura: meta-analysis of populations from the Central Balkans

Climate Research ◽

10.3354/cr01551 ◽

2019 ◽

Vol 77 (3) ◽

pp. 205-217

Author(s):

M Stamenkovic-Radak ◽

B Kenig ◽

M Djurakic ◽

M Jelic ◽

K Eric ◽

...

Keyword(s):

Environmental Variability ◽

Meta Analysis ◽

Drosophila Subobscura ◽

Inversion Polymorphism ◽

And Inversion

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"Kiss Me with those Red Lips": Gender and Inversion in Bram Stoker's Dracula

Representations ◽

10.1525/rep.1984.8.1.99p00856 ◽

1984 ◽

Vol 8 (1) ◽

pp. 107-133 ◽

Cited By ~ 41

Author(s):

Christopher Craft

Keyword(s):

And Inversion

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Analysis of the Bias Dependent Spectral Response of a-SiC:H p-i-n Photodiode

MRS Proceedings ◽

10.1557/proc-715-a7.3 ◽

2002 ◽

Vol 715 ◽

Author(s):

P. Louro ◽

A. Fantoni ◽

Yu. Vygranenko ◽

M. Fernandes ◽

M. Vieira

Keyword(s):

Bias Voltage ◽

Voltage Dependence ◽

Spectral Response ◽

Surface Recombination ◽

Electrical Field ◽

Field Reversal ◽

Current Voltage ◽

Voltage Dependent ◽

And Inversion ◽

Device Operation

AbstractThe bias voltage dependent spectral response (with and without steady state bias light) and the current voltage dependence has been simulated and compared to experimentally obtained values. Results show that in the heterostructures the bias voltage influences differently the field and the diffusion part of the photocurrent. The interchange between primary and secondary photocurrent (i. e. between generator and load device operation) is explained by the interaction of the field and the diffusion components of the photocurrent. A field reversal that depends on the light bias conditions (wavelength and intensity) explains the photocurrent reversal. The field reversal leads to the collapse of the diode regime (primary photocurrent) launches surface recombination at the p-i and i-n interfaces which is responsible for a double-injection regime (secondary photocurrent). Considerations about conduction band offsets, electrical field profiles and inversion layers will be taken into account to explain the optical and voltage bias dependence of the spectral response.

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