Sodium-pump density of cells from dog tracheal mucosa

1985 ◽  
Vol 248 (5) ◽  
pp. C389-C398 ◽  
Author(s):  
J. H. Widdicombe ◽  
C. B. Basbaum ◽  
E. Highland
Keyword(s):  
Surface Area ◽  
Sodium Pump ◽  
Apical Membrane ◽  
Cell Types ◽  
Total Surface Area ◽  
Basal Cells ◽  
Tracheal Mucosa ◽  
Average Surface ◽  
Surface Areas ◽  
Average Surface Area

Uptake of tritiated ouabain by cells isolated from dog tracheal epithelium showed two components: a saturable component with a Km of 5.1 X 10(-8) M and a maximal uptake of 8.3 X 10(5) molecules/cell and a nonsaturating component of uptake that was linear with concentration. Several criteria indicated that the saturable uptake component represented binding to the Na+-K+-ATPase. To estimate the average surface area per cell, a known number of cells were pelleted and weighed, and the average surface area was calculated, assuming the cells to be perfectly spherical. The validity of this assumption was confirmed by comparing the calculated surface areas of cells in isotonic and hypotonic media. From the values for maximal saturable uptake and average surface area, a pump density of approximately 2,400 sites/micron2 was calculated. Given that the apical membrane lacks Na pumps and accounts for only approximately 5% of the total surface area, this value corresponds to the pump density of the basolateral cell membrane. The pump densities of ciliated, goblet, and basal cells were compared by autoradiography. The three cell types had approximately the same density of pump sites.

Size, shape, and surface area of beaver, Castor canadensis, a semiaquatic mammal

1993 ◽  
Vol 71 (5) ◽  
pp. 876-882 ◽  
Author(s):  
P. S. Reynolds
Keyword(s):  
Surface Area ◽  
Body Mass ◽  
Marine Mammal ◽  
Body Shape ◽  
Castor Canadensis ◽  
Total Surface Area ◽  
Energetic Efficiency ◽  
Terrestrial Mammals ◽  
Surface Areas ◽  
Average Surface Area

The beaver, Castor canadensis, is a large, herbivorous, semiaquatic rodent. Beaver forage on land as well as in water; thus functional compromise between competing activities should result in a less streamlined body shape than expected for a similarly sized marine mammal. Standard morphometrics and surface areas of 70 Wisconsin beaver ranging in size from 5 to 35 kg were measured. Geometric similarity of surface area was maintained during growth (i.e., area was proportional to body mass raised to the 2/3 power). Scaly-tail area was positively allometric with body mass; hind foot web area was weakly negatively allometric. The surface area of the unfurred extremities (hind feet and scaly tail) comprised 30% of the total surface area of adults and over 50% for younger beaver. The average surface area of 21 adult beaver (mean body mass = 20 kg) was 0.52 m2. This value was significantly lower (P < 0.001) than predicted from the Meeh equation for terrestrial mammals, but similar to that expected for a marine mammal of equivalent mass. Body shape was described by the fineness ratio (a hydrodynamic index of streamlining). The fineness ratio for beaver was 4.8, a value similar to that for phocid seals. Therefore, in spite of expected constraints on body shape imposed by herbivory and the competing demands of terrestrial and aquatic foraging, beaver do not differ significantly in overall shape from other, more aquatic, species. However, shape alone is not a reliable indicator of either hydrodynamic or energetic efficiency. Future comparative studies should incorporate both phylogeny and biomechanical data into evaluations of mammalian morphology.

scholarly journals Surface area analysis in edentulous jaws of patients with skeletal class I

2011 ◽  
Vol 58 (4) ◽  
pp. 209-215 ◽  
Author(s):  
Srdjan Postic
Keyword(s):  
Surface Area ◽  
Class I ◽  
Anthropometric Parameter ◽  
Average Surface ◽  
Skeletal Class ◽  
Surface Areas ◽  
Significant Difference ◽  
Average Surface Area ◽  
The Right ◽  
Edentulous Jaws

Introduction. The surface area of edentulous jaw has been considered as an important functional and anthropometric parameter. The aim of this study was to assess the surface area of supporting tissue in edentulous jaws of patients with the skeletal class I. Material and Methods. Thin aluminum foils (0.5 mm of thickness) were adapted on plaster surfaces of 139 pairs of edentulous jaws casts. Foils were positioned on a millimeter-paper in order to measure their areas. Additionally, surface areas were measured using a mechanic plan-meter (G. Coradi, Zurich, Switzerland, serial no. 49823). The measurement error was 1%. Skeletal class of edentulous jaws was determined by analysis of lateral cephalometric radiographs, and assessing the ANB (SNA, SNB) angle. Results. The average surface area of edentulous upper jaws was 4654?407 mm2 in males, and 4212?368 mm2 in females. Edentulous lower jaws had average surface area of 2843?339 mm2 in males, and 2334?295 mm2 in females. Statistically significant difference (p<0.001) was found in comparison of surface areas and dimensions of upper and lower edentulous jaws in male and female. ANB values ranged from 2 to 4 degrees. Conclusion. The surface area is an important parameter in the analysis of edentulous jaws. Edentulous jaws in males had greater surface areas and dimensions as compared to females. Edentulous areas on the right side were not absolutely symmetric to areas on the left side.

scholarly journals Investigation of surface area of lakes and marshes from satellite images by using remote sensing and geographic information system integration in Iraq

2018 ◽  
Vol 162 ◽  
pp. 03016
Author(s):  
Alaa Dawood ◽  
Yousif Kalaf ◽  
Nagham Abdulateef ◽  
Mohammed Falih
Keyword(s):  
Remote Sensing ◽  
Surface Area ◽  
System Integration ◽  
Hydrological Regime ◽  
Remotely Sensed ◽  
Total Surface Area ◽  
Water Levels ◽  
Remotely Sensed Data ◽  
Surface Areas ◽  
Water Volumes

Water level and distribution is very essential in almost all life aspects. Natural and artificial lakes represent a large percentage of these water bodies in Iraq. In this research the changes in water levels are observed by calculating the areas of five different lakes in five different regions and two different marshes in two different regions of the country, in a period of 12 years (2001 - 2012), archived remotely sensed images were used to determine surface areas around lakes and marshes in Iraq for the chosen years . Level of the lakes corresponding to satellite determined surface areas were retrieved from remotely sensed data .These data were collected to give explanations on lake level and surface area fluctuations. It is important to determine these areas at different water levels to know areas which are being flooded in addition to the total area inundated .The behavior of hydrological regime of these lakes during the period was assessed using an integration of remote sensing and GIS techniques which found that the total surface area of the lakes had diminished and their water volumes reduced. The study further revealed that the levels of the lakes surfaces had lowered through these years.

scholarly journals Relation between leaf number and final leaf area of rye.

1964 ◽  
Vol 12 (1) ◽  
pp. 30-39
Author(s):  
R.F. Hoogland
Keyword(s):  
Leaf Area ◽  
Surface Area ◽  
Correlation Coefficients ◽  
Leaf Number ◽  
Total Leaf Area ◽  
Average Surface ◽  
Flag Leaves ◽  
Average Surface Area ◽  
Number Of Leaves ◽  
The Relationship

In rye cv. Petkus and Zelder the date of emergence of the flag leaves was almost the same for all plants irrespective of the number of leaves (10-13) produced. Correlation coefficients for the relationship between total leaf area and number of leaves were + 0.45 and + 0.44 and for that between number of spikelets per ear and number of leaves + 0.61 and + 0.69 for the 2 varieties, respectively. Average surface area per leaf increased with increasing number of leaves.-R.B. (Abstract retrieved from CAB Abstracts by CABI’s permission)

scholarly journals Investigation of Long and Short-Term Water Surface Area Changes in Coastal Ramsar Sites in Turkey with Google Earth Engine

2022 ◽  
Vol 11 (1) ◽  
pp. 46
Author(s):  
Adalet Dervisoglu
Keyword(s):  
Surface Area ◽  
Water Surface ◽  
Google Earth ◽  
Short Term ◽  
Annual Average ◽  
Surface Areas ◽  
Inland Wetlands ◽  
Increasing Trend ◽  
Average Surface Area ◽  
Term Analysis

Deltas and lagoons, which contain many flora and fauna, have rich coastal ecological and biological environments, and are wetlands of vital importance for humans. In this study, the current problems in all coastal Ramsar sites in Turkey are summarized, and changes in water surface areas are investigated using Landsat and Sentinel 1/2 satellite images on the Google Earth Engine (GEE) cloud computing platform. Landsat TM and OLI images were used in the long-term analysis, and time series were created by taking annual and July to September averages between 1985 and 2020. In the short-term analysis, monthly averages were determined using Sentinel 2 images between 2016 and 2020. Sentinel-1 Synthetic Aperture Radar (SAR) images were used in the months when optical data were not suitable for use in monthly analysis. The Normalized Difference Water Index (NDWI) was used to extract water surface areas from the optical images. Afterwards, a thresholding process was used for both optical and radar images to determine the changes. The changes were analyzed together with the meteorological data and the information obtained from the management plans and related studies in the literature. Changes in the water surface areas of all coastal Ramsar sites in Turkey were determined from 1985 to 2020 at different rates. There was a decreasing trend in the Goksu and Kızılırmak Deltas, which also have inland wetlands. The decreasing rates from 1985 to 2020 were −24.52% and −2.86%, for annual average water surfaces for the Goksu and Kızılırmak Deltas, respectively, and −21.64% and −6.34% for the dry season averages, respectively. However, Akyatan Lagoon, which also has inland wetlands, showed an increasing trend. Observing the annual average surface area from 1985 to 2020, an increase of 438 ha was seen, corresponding to 7.65%. Every year, there was an increasing trend in the Gediz Delta and Yumurtalık Lagoons, that do not have inland wetlands. The increasing rates from 1985 to 2020 were 46.01% and 17.31% for the annual average surface area, for the Gediz Delta and Yumurtalık Lagoons, respectively, and 38.34% and 21.04% for the dry season average, respectively. The obtained results reveal the importance of using remote sensing methods in formulating strategies for the sustainable management of wetlands.

A stereological comparison of villous and microvillous surfaces in small intestines of frugivorous and entomophagous bats: species, inter-individual and craniocaudal differences.

1997 ◽  
Vol 200 (18) ◽  
pp. 2415-2423 ◽  
Author(s):  
A N Makanya ◽  
J N Maina ◽  
T M Mayhew ◽  
S A Tschanz ◽  
P H Burri
Keyword(s):  
Surface Area ◽  
Body Mass ◽  
Membrane Surface ◽  
Total Surface Area ◽  
Membrane Surface Area ◽  
Intestinal Tube ◽  
Surface Areas ◽  
Intestinal Length ◽  
Mass Coefficient ◽  
Extensive Surface

The extents of functional surfaces (villi, microvilli) have been estimated at different longitudinal sites, and in the entire small intestine, for three species of bats belonging to two feeding groups: insect- and fruit-eaters. In all species, surface areas and other structural quantities tended to be greatest at more cranial sites and to decline caudally. The entomophagous bat (Miniopterus inflatus) had a mean body mass (coefficient of variation) of 8.9 g (5%) and a mean intestinal length of 20 cm (6%). The surface area of the basic intestinal tube (primary mucosa) was 9.1 cm2 (10%) but this was amplified to 48 cm2 (13%) by villi and to 0.13 m2 (20%) by microvilli. The total number of microvilli per intestine was 4 x 10(11) (20%). The average microvillus had a diameter of 8 nm (10%), a length of 1.1 microns (22%) and a membrane surface area of 0.32 micron 2 (31%). In two species of fruit bats (Epomophorus wahlbergi and Lisonycteris angolensis), body masses were greater and intestines longer, the values being 76.0 g (18%) and 76.9 g (4%), and 73 cm (16%) and 72 cm (7%), respectively. Surface areas were also greater, amounting to 76 cm2 (26%) and 45 cm2 (8%) for the primary mucosa, 547 cm2 (29%) and 314 cm2 (16%) for villi and 2.7 m2 (23%) and 1.5 m2 (18%) for microvilli. An increase in the number of microvilli, 33 x 10(11) (19%) and 15 x 10(11) (24%) per intestine, contributed to the more extensive surface area but there were concomitant changes in the dimensions of microvilli. Mean diameters were 94 nm (8%) and 111 nm (4%), and mean lengths were 2.8 microns (12%) and 2.9 microns (10%), respectively. Thus, an increase in the surface area of the average microvillus to 0.83 micron 2 (12%) and 1.02 microns 2 (11%) also contributed to the greater total surface area of microvilli. The lifestyle-related differences in total microvillous surface areas persisted when structural quantities were normalised for the differences in body masses. The values for total microvillous surface area were 148 cm2g-1 (20%) in the entomophagous bat, 355 cm2g-1 (20%) in E. wahlbergi and 192 cm2g-1 (17%) in L. angolensis. This was true despite the fact that the insecteater possessed a greater length of intestine per unit of body mass: 22 mm g-1 (8%) versus 9-10 mm g-1 (9-10%) for the fruit-eaters.

Morphology and dimensions of the young comendite lavas of La Primavera volcano, Mexico

1982 ◽  
Vol 119 (5) ◽  
pp. 477-485 ◽  
Author(s):  
B. J. Clough ◽  
J. V. Wright ◽  
G. P. L. Walker
Keyword(s):  
Surface Area ◽  
Quantitative Data ◽  
Average Thickness ◽  
Ring Fracture ◽  
Dry Land ◽  
Average Surface ◽  
Aspect Ratios ◽  
Average Surface Area ◽  
Special Environment ◽  
Lake Deposits

SummaryQuantitative data on the rhyolitic lavas of the Quaternary La Primavera volcano, Mexico, are presented. Lavas vary in form from domes and mesa lavas to short coulées. Average thickness is 100 m, average surface area is 2.7 km2 and aspect ratios vary from 1:7 to 1:25. Two petrological lava types are distinguished – porphyritic and aphyric. Porphyritic lavas occur on or within an inner ring fracture and are associated with an area of caldera lake deposits. Many features suggest that these porphyritic lavas were emplaced into the wet sediments or water of the caldera lake. Aphyric lavas are largely found to the south of this region and form large polygenetic structures extruded on dry land. The porphyritic lavas generally are smaller and have higher aspect ratios than the aphyric, which are attributed to their special environment of emplacement. Some porphyritic lavas extruded on dry land, outside the region occupied by the caldera lake, are, however, the thinnest on the volcano.

Characteristics of magnetically separated rat tracheal epithelial cell populations

1992 ◽  
Vol 263 (5) ◽  
pp. L568-L574 ◽  
Author(s):  
J. R. Ford ◽  
M. Terzaghi-Howe
Keyword(s):  
Basal Cell ◽  
Significant Proportion ◽  
Cell Types ◽  
Cell Fraction ◽  
Secretory Cells ◽  
Basal Cells ◽  
Proliferative Capacity ◽  
Tracheal Mucosa ◽  
Tracheal Epithelial

A simple magnetic separation technique has been developed using lectins specific for two of the cell types found in the tracheal mucosa. The resulting populations of basal and secretory cells were examined for proliferative capacity in culture and in vivo. The basal cell fraction contains the cells that proliferate in culture and respond to 12-O-tetradecanoylphorbol-13-acetate. In addition, the basal cell fraction exhibited the highest proliferative capacity in vivo during the first few days after transplantation. Repopulation of inverted intestinal segments showed that only with suspensions containing a significant proportion of basal cells could a mucociliary lining be established. Segments receiving the same number of unsorted or predominantly mucous secreting cells did not repopulate in vivo. These data support the hypothesis that the basal cell is most likely the stem cell of the tracheal epithelium.

Pore size distribution and adsorption selectivity of sepiolite

Clay Minerals ◽  
1990 ◽  
Vol 25 (1) ◽  
pp. 99-105 ◽  
Author(s):  
S. Inagaki ◽  
Y. Fukushima ◽  
H. Doi ◽  
O. Kamigaito
Keyword(s):  
Surface Area ◽  
Outer Surface ◽  
Adsorbed Water ◽  
Total Surface Area ◽  
Effective Size ◽  
Adsorption Selectivity ◽  
Surface Areas ◽  
Bet Method ◽  
The Mean ◽  
The Difference

AbstractMicropore distribution and effective size of the channels of natural sepiolite from Turkey were measured by the BET method. Before the BET measurement, the samples were treated under a water vapour atmosphere at various pressures to fill progressively the sepiolite micropores with water. The surface areas measured by means of N2 adsorption decreased with increased vapour pressures of water. The outer surface area was estimated by comparison of the surface area of the vacuum-dried sepiolite with that filled with adsorbed water. The total surface area was ∼290 m2/g, and the outer surface area was 170 m2/g, the difference being attributed to the structural micropores of the sepiolite. The ratio of the surface areas possessed by the channels and that of the outer surface suggest that the mean thickness of the sepiolite fibre was ∼12 nm. The effective size of the channels was estimated from the number of various-sized molecules sorbed by the sepiolite, the results showing that molecules larger than benzene could not migrate into the channels.

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