Forces Behind Structural Changes: A Quantitative Analysis of Indian Corporate Sector

We show detailed understanding of enzyme dependent structural changes in supercoiled DNA along with a quantitative analysis of its branches using nanopores.

Download Full-text

Application of Infrared Absorption Spectra to Studies of the Oxidation of Sodium-Butadiene Rubber

Rubber Chemistry and Technology ◽

10.5254/1.3543088 ◽

1951 ◽

Vol 24 (3) ◽

pp. 591-596

Author(s):

B. Dogadkin ◽

B. Kasatochkin ◽

N. Klauzen ◽

A. Smirnova

Keyword(s):

Quantitative Analysis ◽

Molecular Oxygen ◽

Structural Changes ◽

Chemical Properties ◽

Butadiene Rubber ◽

Physical And Chemical Properties ◽

Reaction Products ◽

Infrared Absorption Spectra ◽

Physical And Chemical ◽

And Chemical Properties

Abstract The reaction of rubber with molecular oxygen explains well the structural changes which take place in rubber during aging and during a number of important technological processes, such as plasticization and vulcanization. Furthermore, during vulcanization, in addition to its reaction with the vulcanizing agent, rubber also reacts with oxygen contained in the mixture. This may be one of the reasons for an optimum point of vulcanization. However, it is difficult to explain the changes of physical properties of rubber by simple union of oxygen, with formation of oxygen-bearing groups. To account for the changes observed, addition of a large quantity of oxygen would be necessary, whereas actually notable changes are brought about by the absorption of only 2–3 per cent of oxygen. To explain this, it must be assumed that oxygen causes structural changes in rubber and that these changes become evident when the percentage of oxygen in the reaction products is still negligible. In the case of sodium-butadiene rubber, as was shown by one of the authors, this reaction at any particular temperature causes an increase of strength and of elasticity, and a loss of solubility. The object of the present investigation was a qualitative and limited quantitative analysis of those groups which originate during oxidation and also an examination of the structures which determine the changes of the physical and chemical properties in the reaction of rubber with molecular oxygen.

Download Full-text

Automated Sectoral Quantitative Analysis of Parafoveal Microvascular Status and Association with Structure in Diabetic Macular Edema

10.21203/rs.3.rs-561485/v1 ◽

2021 ◽

Author(s):

Nihat Polat ◽

Saim Yoloğlu

Keyword(s):

Quantitative Analysis ◽

Macular Edema ◽

Diabetic Macular Edema ◽

Structural Changes ◽

Vessel Density ◽

External Limiting Membrane ◽

Ellipsoid Zone ◽

Capillary Plexus ◽

Temporal Quadrant ◽

Superficial Capillary Plexus

Abstract Purpose: To evaluate the integrity of the capillary plexuses, their relationship with each other, and their association with structural changes in a sectoral manner in diabetic macular edema (DME).Methods: The vessel density (VD) was measured in inferior, superior, nasal and temporal (İ, S, N, T) parafovea in the superficial capillary plexus (SCP) and deep capillary plexus (DCP). The integrity of the external limiting membrane (ELM) and ellipsoid zone (EZ) were evaluated in B-scan images.Results: In the SCP, only superior and nasal VD was significantly lower (P: 0.0001 and P: 0.020, respectively) while in the DCP, only temporal VD was significantly lower in the DME eyes (P: 0.034). There was no correlation between the VD of SCP and DCP in the corresponding quadrants (all P > 0.05). The FAZ area was significantly greater (both superficial and deep) in DME eyes than in control eyes (P > 0.05). ELM disruptions were not affected by the corresponding VDs in the SCP (all P> 0.05), but nasal and temporal quadrant ELM disruptions were affected by VDs in the DCP in the corresponding quadrants (P: 0.005 nasal, P: 0.001 temporal). EZ disruptions were not affected by the corresponding VDs in the SCP and DCP (all P> 0.05).Conclusions: The SCP was affected in more quadrants than the DCP and probably independently from each other. There was an association with the ELM and the DCP, especially in nasal and temporal quadrants, but there was not an association between the EZ and SCP or DCP.

Download Full-text

QUANTITATIVE ANALYSIS OF COLLAGEN LEVELS AND EARLY STRUCTURAL CHANGES IN TESTES OF RATS WITH EXPERIMENTALLY INDUCED LEFT VARICOCELE

The Journal of Urology ◽

10.1097/00005392-199904020-00394 ◽

1999 ◽

pp. 348

Author(s):

Tahir Turan ◽

Omer L. Tuncay ◽

Mehmet H. Koseoglu ◽

Zafer Aybek ◽

Ozcan Atahan ◽

...

Keyword(s):

Quantitative Analysis ◽

Structural Changes ◽

Experimentally Induced

Download Full-text

A quantitative analysis of triglyceride droplet structural changes in hamster brown adipose tissue during cold exposure and starvation

Journal of Ultrastructure Research ◽

10.1016/s0022-5320(74)80006-7 ◽

1974 ◽

Vol 48 (3) ◽

pp. 361-376 ◽

Cited By ~ 11

Author(s):

Iréne Ahlabo ◽

Tudor Barnard

Keyword(s):

Adipose Tissue ◽

Quantitative Analysis ◽

Brown Adipose Tissue ◽

Cold Exposure ◽

Structural Changes ◽

Brown Adipose

Download Full-text

Fine Structural Changes in the Microvasculature of the Mouse Pinna: Aging and Radiation Injury

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100050287 ◽

1974 ◽

Vol 32 ◽

pp. 54-55

Author(s):

S. Phyllis Steamer ◽

Rosemarie L. Devine

Keyword(s):

Structural Changes ◽

Radiation Treatment ◽

Arterial Stenosis ◽

Ultrastructural Changes ◽

Vascular Effects ◽

Microvascular Changes ◽

Surrounding Connective Tissue ◽

Fission Neutrons ◽

Total Body

The importance of radiation damage to the skin and its vasculature was recognized by the early radiologists. In more recent studies, vascular effects were shown to involve the endothelium as well as the surrounding connective tissue. Microvascular changes in the mouse pinna were studied in vivo and recorded photographically over a period of 12-18 months. Radiation treatment at 110 days of age was total body exposure to either 240 rad fission neutrons or 855 rad 60Co gamma rays. After in vivo observations in control and irradiated mice, animals were sacrificed for examination of changes in vascular fine structure. Vessels were selected from regions of specific interest that had been identified on photomicrographs. Prominent ultrastructural changes can be attributed to aging as well as to radiation treatment. Of principal concern were determinations of ultrastructural changes associated with venous dilatations, segmental arterial stenosis and tortuosities of both veins and arteries, effects that had been identified on the basis of light microscopic observations. Tortuosities and irregularly dilated vein segments were related to both aging and radiation changes but arterial stenosis was observed only in irradiated animals.

Download Full-text

Evaluation of single-electron movies of glutamine synthetase molecules

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100075191 ◽

1983 ◽

Vol 41 ◽

pp. 280-281

Author(s):

W. Kunath ◽

E. Zeitler ◽

M. Kessel

Keyword(s):

Electron Microscope ◽

Glutamine Synthetase ◽

Electron Irradiation ◽

Structural Damage ◽

Structural Changes ◽

Single Electron ◽

Continuous Series ◽

Digital Recording ◽

Recording Device ◽

Low Exposure

The features of digital recording of a continuous series (movie) of singleelectron TV frames are reported. The technique is used to investigate structural changes in negatively stained glutamine synthetase molecules (GS) during electron irradiation and, as an ultimate goal, to look for the molecules' “undamaged” structure, say, after a 1 e/Å2 dose.The TV frame of fig. la shows an image of 5 glutamine synthetase molecules exposed to 1/150 e/Å2. Every single electron is recorded as a unit signal in a 256 ×256 field. The extremely low exposure of a single TV frame as dictated by the single-electron recording device including the electron microscope requires accumulation of 150 TV frames into one frame (fig. lb) thus achieving a reasonable compromise between the conflicting aspects of exposure time per frame of 3 sec. vs. object drift of less than 1 Å, and exposure per frame of 1 e/Å2 vs. rate of structural damage.

Download Full-text