Ventilation Frequency Reveals the Roles of Exchange Surface Areas in Metabolic Scaling

2020 ◽  
Vol 93 (1) ◽  
pp. 13-22 ◽  
Author(s):  
Yiping Luo ◽  
Qian Li ◽  
Xiaoling Zhu ◽  
Jing Zhou ◽  
Cong Shen ◽  
...  
Keyword(s):  
Metabolic Scaling ◽  
Ventilation Frequency ◽  
Surface Areas ◽  
Exchange Surface

scholarly journals Estimates and relationships between aboveground and belowground resource exchange surface areas in a Sitka spruce managed forest

2010 ◽  
Vol 30 (6) ◽  
pp. 705-714 ◽  
Author(s):  
A. J. Butler ◽  
N. Barbier ◽  
J. Cermak ◽  
J. Koller ◽  
C. Thornily ◽  
...  
Keyword(s):  
Sitka Spruce ◽  
Managed Forest ◽  
Resource Exchange ◽  
Surface Areas ◽  
Exchange Surface

The Placenta in Pre-eclampsia and Intrauterine Growth Restriction: Studies on Exchange Surface Areas, Diffusion Distances and Villous Membrane Diffusive Conductances

Placenta ◽  
2007 ◽  
Vol 28 (2-3) ◽  
pp. 233-238 ◽  
Author(s):  
T.M. Mayhew ◽  
R. Manwani ◽  
C. Ohadike ◽  
J. Wijesekara ◽  
P.N. Baker
Keyword(s):  
Intrauterine Growth Restriction ◽  
Growth Restriction ◽  
Intrauterine Growth ◽  
Surface Areas ◽  
Exchange Surface

scholarly journals Are the surface areas of the gills and body involved with changing metabolic scaling with temperature?

2018 ◽  
Vol 221 (8) ◽  
pp. jeb174474 ◽  
Author(s):  
Ge Li ◽  
Xiao Lv ◽  
Jing Zhou ◽  
Cong Shen ◽  
Danyang Xia ◽  
...  
Keyword(s):  
Metabolic Scaling ◽  
Surface Areas

Respiratory Adaptations of Prenatal Young in the Ovary of two Species of Viviparous Seaperch, Rhacochilus vacca and Embiotoca lateralis

1972 ◽  
Vol 29 (11) ◽  
pp. 1525-1542 ◽  
Author(s):  
P. W. Webb ◽  
J. R. Brett
Keyword(s):  
Flow Characteristics ◽  
Weight Ratio ◽  
Late Gestation ◽  
Ovarian Fluid ◽  
Ovary Weight ◽  
Surface Areas ◽  
Maximum Value ◽  
Embiotoca Lateralis ◽  
And Diffusion ◽  
Exchange Surface

The structure of the ovary and embryos of embiotocids is reviewed in relation to those factors that would affect the exchange of materials between ovarian and embryonic blood streams. Weight, exchange surface areas (particularly of the fins), diffusion distances, and capillary densities were measured for prenatal young and ovaries of two species of Embiotocidae, Rhacochilus vacca and Embiotoca lateralis, during middle and late gestation. Brood size and ovarian fluid volume were also measured. Changes in brood weight and ovarian fluid volumes were interpreted in relation to the load imposed on the ovary by the young. This was expressed as the brood/ovary weight ratio which was found to increase during gestation to a maximum value of eight. Changes in exchange surface areas and diffusion distances of the young and the ovary were determined and evaluated in relation to the metabolic requirements of the brood. Convection of the ovarian fluid must occur as a necessary mechanism for efficient exchange of materials with increasing brood/ovary weight ratio. It is further concluded that the supply of materials to the brood would be limited by ovarian blood-flow characteristics rather than structural considerations, except immediately prior to parturition.

Retinoic acid induces nonuniform alveolar septal growth after right pneumonectomy

2004 ◽  
Vol 96 (3) ◽  
pp. 1080-1089 ◽  
Author(s):  
Xiao Yan ◽  
Dennis J. Bellotto ◽  
David J. Foster ◽  
Robert L. Johnson ◽  
Herbert K. Hagler ◽  
...  
Keyword(s):  
Retinoic Acid ◽  
Volume Ratio ◽  
Volume Density ◽  
Surface Areas ◽  
All Trans Retinoic Acid ◽  
Septal Thickness ◽  
Lower Volume ◽  
Cell Volumes ◽  
Exchange Surface ◽  
Alveolar Capillary

To determine whether all- trans retinoic acid (RA) enhances compensatory lung growth in fully mature animals, adult male dogs ( n = 4) received 2 mg·kg-1·day-1 po RA 4 days/wk beginning the day after right pneumonectomy (R-PNX, 55-58% resection). Litter-matched male R-PNX controls ( n = 4) received placebo. After 4 mo, the remaining lung was fixed by tracheal instillation of fixatives at a constant airway pressure for detailed morphometric analysis. After RA treatment compared with placebo, lung volume was slightly but not significantly lower. Volume density of septum to lung was 37% higher because of a 50 and 25% higher volume density of capillary and septal tissue, respectively. Mean septal thickness was 27% higher. Absolute volumes of endothelial cells and capillary blood were 31-37% higher, whereas epithelial and interstitial volumes were not different between groups. Absolute alveolar-capillary surface areas did not differ between groups, and alveolar septal surface-to-volume ratio was 20% lower in RA-treated animals. RA treatment exaggerated interlobar differences in morphometric indexes and caused alveolar capillary morphology to revert to a more immature state. Thus RA treatment during early post-R-PNX adaptation preferentially enhanced alveolar capillary and endothelial cell volumes consistent with formation of new capillaries, but the associated septal distortion precluded a corresponding increase in gas-exchange surface or morphometric estimates of lung diffusing capacity.

Cerebral Tissue Response in Chronic Electrode Implantation

1977 ◽  
Vol 35 ◽  
pp. 624-625
Author(s):  
R.F. Dodson ◽  
L.W-F Chu ◽  
N. Ishihara
Keyword(s):  
Tissue Response ◽  
Whole Body ◽  
Platinum Electrodes ◽  
Fixed Tissue ◽  
Electrode Implantation ◽  
Surface Areas ◽  
Tissue Changes ◽  
Micron Diameter ◽  
Extent Of Damage ◽  
Electrode Sheath

The extent of damage surrounding an implanted electrode in the cerebral cortex is a question of significant importance with regard to attaining consistency and validity of physiological recordings. In order to determine the extent of such tissue changes, 150 micron diameter platinum electrodes were implanted in the cortex of four adult baboons, and after eight days the animals were sacrificed by whole body perfusion with a 3% glutaraldehyde in 0.1M phosphate fixative.The calvarium was carefully removed and the electrode tracts were readily discernible in the firm, glutaraldehyde fixed tissue.Careful dissection of the zone of the electrode tract resulted in a small block which was further sectioned into tip, mid-tract and surface areas. Ultrastructurally, damage extended from the electrode sheath to the greatest extent of from 0.2 to 3.5 mm.

Tissue section lifting for electron microscopy

1978 ◽  
Vol 36 (2) ◽  
pp. 86-87
Author(s):  
Adrian F. van Dellen
Keyword(s):  
Infectious Disease ◽  
Electron Microscopy ◽  
Tissue Culture ◽  
Organ System ◽  
Surrounding Tissue ◽  
Paraffin Sections ◽  
Surface Areas ◽  
Specific Determination ◽  
High Degree ◽  
Accuracy And Repeatability

The morphologic pathologist may require information on the ultrastructure of a non-specific lesion seen under the light microscope before he can make a specific determination. Such lesions, when caused by infectious disease agents, may be sparsely distributed in any organ system. Tissue culture systems, too, may only have widely dispersed foci suitable for ultrastructural study. In these situations, when only a few, small foci in large tissue areas are useful for electron microscopy, it is advantageous to employ a methodology which rapidly selects a single tissue focus that is expected to yield beneficial ultrastructural data from amongst the surrounding tissue. This is in essence what "LIFTING" accomplishes. We have developed LIFTING to a high degree of accuracy and repeatability utilizing the Microlift (Fig 1), and have successfully applied it to tissue culture monolayers, histologic paraffin sections, and tissue blocks with large surface areas that had been initially fixed for either light or electron microscopy.

In situ REM imaging of surface processes on ceramic bulk crystals from 300 to 1670 K in a conventional TEM

1991 ◽  
Vol 49 ◽  
pp. 660-661
Author(s):  
Z. L. Wang ◽  
J. Bentley
Keyword(s):  
High Temperatures ◽  
Image Resolution ◽  
Atomic Processes ◽  
Crystal Surfaces ◽  
Beam Radiation ◽  
Surface Areas ◽  
Transmission Electron ◽  
Reflection Electron Microscopy ◽  
Gas Reactions

Studying the behavior of surfaces at high temperatures is of great importance for understanding the properties of ceramics and associated surface-gas reactions. Atomic processes occurring on bulk crystal surfaces at high temperatures can be recorded by reflection electron microscopy (REM) in a conventional transmission electron microscope (TEM) with relatively high resolution, because REM is especially sensitive to atomic-height steps.Improved REM image resolution with a FEG: Cleaved surfaces of a-alumina (012) exhibit atomic flatness with steps of height about 5 Å, determined by reference to a screw (or near screw) dislocation with a presumed Burgers vector of b = (1/3)<012> (see Fig. 1). Steps of heights less than about 0.8 Å can be clearly resolved only with a field emission gun (FEG) (Fig. 2). The small steps are formed by the surface oscillating between the closely packed O and Al stacking layers. The bands of dark contrast (Fig. 2b) are the result of beam radiation damage to surface areas initially terminated with O ions.

Cell morphology, volume, and surface area determinations from multilevel contouring within HVEM micrographs of serial sections and whole-cell mounts

1987 ◽  
Vol 45 ◽  
pp. 588-589
Author(s):  
M. Marko ◽  
A. Leith ◽  
D. Parsons
Keyword(s):  
Surface Area ◽  
Electron Micrographs ◽  
Cell Morphology ◽  
Individual Variation ◽  
Serial Section ◽  
Stereo Pair ◽  
Complex Structures ◽  
Serial Sections ◽  
Surface Areas ◽  
Computer Based

The use of serial sections and computer-based 3-D reconstruction techniques affords an opportunity not only to visualize the shape and distribution of the structures being studied, but also to determine their volumes and surface areas. Up until now, this has been done using serial ultrathin sections.The serial-section approach differs from the stereo logical methods of Weibel in that it is based on the Information from a set of single, complete cells (or organelles) rather than on a random 2-dimensional sampling of a population of cells. Because of this, it can more easily provide absolute values of volume and surface area, especially for highly-complex structures. It also allows study of individual variation among the cells, and study of structures which occur only infrequently.We have developed a system for 3-D reconstruction of objects from stereo-pair electron micrographs of thick specimens.

Hair cell changes after cationic stimulation of corti's organ

1989 ◽  
Vol 47 ◽  
pp. 798-799
Author(s):  
Cesar D. Fermin ◽  
Hans-Peter Zenner
Keyword(s):  
Organ Of Corti ◽  
Cross Sectional ◽  
Surface Areas ◽  
High K ◽  
Anatomical Arrangement ◽  
Cell Cytosol ◽  
High Concentrations ◽  
K Concentration ◽  
Cell Changes

Contraction of outer and inner hair cells (OHC&IHC) in the Organ of Corti (OC) of the inner ear is necessary for sound transduction. Getting at HC in vivo preparations is difficult. Thus, isolated HCs have been used to study OHC properties. Even though viability has been shown in isolated (iOHC) preparations by good responses to current and cationic stimulation, the contribution of adjoining cells can not be explained with iOHC preparations. This study was undertaken to examine changes in the OHC after expossure of the OHC to high concentrations of potassium (K) and sodium (Na), by carefully immersing the OC in either artifical endolymph or perilymph. After K and Na exposure, OCs were fixed with 3% glutaraldehyde, post-fixed in osmium, separated into base, middle and apex and embedded in Araldite™. One μm thick sections were prepared for analysis with the light and E.M. Cross sectional areas were measured with Bioquant™ software.Potassium and sodium both cause isolated guinea pig OHC to contract. In vivo high K concentration may cause uncontrolled and sustained contractions that could contribute to Meniere's disease. The behavior of OHC in the vivo setting might be very different from that of iOHC. We show here changes of the cell cytosol and cisterns caused by K and Na to OHC in situs. The table below shows results from cross sectional area measurements of OHC from OC that were exposed to either K or Na. As one would expect, from the anatomical arrangement of the OC, OHC#l that are supported by rigid tissue would probably be displaced (move) less than those OHC located away from the pillar. Surprisingly, cells in the middle turn of the cochlea changed their surface areas more than those at either end of the cochlea. Moreover, changes in surface area do not seem to differ between K and Na treated OCs.

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