scholarly journals Free Oscillations of the Earth Climate System: A Theory of the 100 kyr Climate Cycle

1990 ◽  
Vol 14 ◽  
pp. 346
Author(s):  
R.M. MacKay ◽  
M.A.K. Khalil
Keyword(s):  
Surface Area ◽  
Nonlinear Differential Equations ◽  
Radiation Balance ◽  
Unit Surface Area ◽  
Ocean Temperature ◽  
Free Oscillations ◽  
The Earth ◽  
Climate Cycle ◽  
Unit Surface ◽  
The Mean

A physically plausible theory of the 100 kyr climate cycle is proposed. Free oscillations between the mean ocean temperature and the marine ice-margin colatitude are shown to exist without requiring orbital forcing. It is shown that the curvature of the Earth causes two effects: (1) as the marine ice margin grows towards the equator, the net emmision of radiation (solar and terrestrial) per unit surface area increases; and (2) as the poleward extent of the ocean decreases, the net absorption of radiation per unit surface area increases. These radiation balance considerations, included with a realistic meridional transport of energy from the ocean to the marine-ice region and an atmospheric feedback process enhancing the ocean warming, are combined to form two nonlinear differential equations coupling the mean ocean temperature with the marine-ice margin colatitude. Using physically realistic parameters we are able to reproduce the major features of the 100 kyr climate cycle. This can be seen from Figure I which shows the δ18O record as given by Imbrie and others (1984), plotted against the model output. In addition we have found that the parameters used to obtain the general features of the ice-volume record also predict temperature “spikes” (1 to 2 K. above average) of relatively short duration (5 to 10 kyr) in the mean ocean temperature. We find that there is good qualitative agreement between the model's predicted mean ocean temperature and the estimation of summer sea-surface temperature at RC11-120 presented by Martinson and others (1987).

scholarly journals Free Oscillations of the Earth Climate System: A Theory of the 100 kyr Climate Cycle

1990 ◽  
Vol 14 ◽  
pp. 346-346
Author(s):  
R.M. MacKay ◽  
M.A.K. Khalil
Keyword(s):  
Surface Area ◽  
Nonlinear Differential Equations ◽  
Radiation Balance ◽  
Unit Surface Area ◽  
Ocean Temperature ◽  
Free Oscillations ◽  
The Earth ◽  
Climate Cycle ◽  
Unit Surface ◽  
The Mean

A physically plausible theory of the 100 kyr climate cycle is proposed. Free oscillations between the mean ocean temperature and the marine ice-margin colatitude are shown to exist without requiring orbital forcing. It is shown that the curvature of the Earth causes two effects: (1) as the marine ice margin grows towards the equator, the net emmision of radiation (solar and terrestrial) per unit surface area increases; and (2) as the poleward extent of the ocean decreases, the net absorption of radiation per unit surface area increases. These radiation balance considerations, included with a realistic meridional transport of energy from the ocean to the marine-ice region and an atmospheric feedback process enhancing the ocean warming, are combined to form two nonlinear differential equations coupling the mean ocean temperature with the marine-ice margin colatitude. Using physically realistic parameters we are able to reproduce the major features of the 100 kyr climate cycle. This can be seen from Figure I which shows the δ18O record as given by Imbrie and others (1984), plotted against the model output. In addition we have found that the parameters used to obtain the general features of the ice-volume record also predict temperature “spikes” (1 to 2 K. above average) of relatively short duration (5 to 10 kyr) in the mean ocean temperature. We find that there is good qualitative agreement between the model's predicted mean ocean temperature and the estimation of summer sea-surface temperature at RC11-120 presented by Martinson and others (1987).

Desmosomes in hamster cheek pouch epithelium: their quantitative characterization during epithelial differentiation

1984 ◽  
Vol 66 (1) ◽  
pp. 411-429
Author(s):  
F.H. White ◽  
K. Gohari
Keyword(s):  
Plasma Membrane ◽  
Surface Area ◽  
Cheek Pouch ◽  
Unit Surface Area ◽  
Granular Cells ◽  
Hamster Cheek Pouch ◽  
Average Cell ◽  
Membrane Area ◽  
The Mean ◽  
Granular Layers

Desmosomes in stratified squamous epithelia appear to exhibit quantitative alterations during differentiation. In this work we use stereological and other morphometric methods to quantify these structures in epithelial cells from defined basal, spinous and granular strata. Hamster cheek pouch mucosa from five animals was processed for electron microscopy using strictly standardized techniques and a stratified random sampling procedure was used to obtain micrographs of cells from basal, spinous and granular layers. Stereological intersection counting techniques were used to determine for each layer the relative surface area of plasma membrane occupied by desmosomes (Ss), the number of desmosomes per unit surface area of plasma membrane (Ns), the mean individual desmosomal diameter (delta) and the mean individual desmosomal surface area (s). In addition, estimates of nuclear volume were obtained by direct measurement of nuclear profiles and volume-to-surface ratios were obtained by a combination of point and intersection counting, which enabled estimates for the volume (Vcell) and plasma membrane surface area (SPM) of the ‘average’ cell within each stratum to be acquired. Using this information, it was then possible to calculate both the total surface area (S) and the number (N) of desmosomes on the plasma membranes of average cells. The parameters Ss and Ns showed progressive increases between basal and granular layers, whereas values for delta and s were lower in granular cells when compared with basal and spinous cells. The parameters Vcell, SPM, S and N all increased progressively and significantly during differentiation. Between basal and granular layers, the mean cell volume and surface area had each increased approximately threefold, whereas the surface area and number of desmosomes on the average cell plasma membrane had increased approximately seven- and eleven-fold, respectively. Granular cells thus possess more numerous desmosomes, which occupy a greater proportion of the plasma membrane area but which are individually smaller, when compared with basal and spinous layers.

scholarly journals Mpemba Effect- the Effect of Time

2021 ◽  
Author(s):  
Jianan Wang
Keyword(s):  
Gravitational Field ◽  
Surface Area ◽  
Time Effect ◽  
Light Quantum ◽  
Unit Surface Area ◽  
Heat Flows ◽  
Unit Surface ◽  
Average Wavelength ◽  
Nature Of Time ◽  
The Relationship

This paper draws the following conclusions on the nature of time by analyzing the relationship between time and speed, the relationship between time and gravitational field, the gravitational redshift of the photon, and the black-body radiation theorem: Time on an object is proportional to the amount of energy flowing out (or in) per unit time (observer’s time) per unit surface area of the object. When an object radiates energy outward: t'=μB(T) =μσT 4=μnhν/st Where t’ is the time on the object, μ is a constant, B(T) is the radiosity，the total energy radiated from the unit surface area of the object in unit time (observer’s time), σ is the Stefan-Boltzmann constant, T is the absolute temperature, n is the number of the photons radiated, ν is the average frequency of the photons radiated, s is the surface area of the object and t is the time on the observer. When the object radiates energy outward, the higher the energy density of the space (for example the stronger the gravitational field of the space), the smaller the radiosity B(T) of the object in the space, the longer the average wavelength of the light quantum emitted by the object, the slower the time on the object, the longer the life of the system. When the object radiates energy outward, the faster the object moves relative to the ether, the higher the energy density of the local space in which the object is located, the smaller the radiosity B(T) of the object, the longer the average wavelength of the light quantum radiated by the object, the slower the time on the object, and the longer the life of the system. When the object radiates energy outward, the higher the temperature of the object, the greater the object's radiosity B(T), the shorter the average wavelength of the light quantum radiated by the object, the faster the time on the object, and the shorter the life of the system. Applying the above conclusions about the nature of time, the author analyzes the Mpemba effect and the inverse Mpemba effect, and reaches the following conclusion: the Mpemba effect is the time effect produced when heat flows from objects into space, and the "inverse" Mpemba effect is the time effect produced when heat flows from space into objects.

Long-term experimental study of the aquatic plant system for polluted river water

2002 ◽  
Vol 46 (11-12) ◽  
pp. 217-224 ◽  
Author(s):  
K. Sato ◽  
H. Sakui ◽  
Y. Sakai ◽  
S. Tanaka
Keyword(s):  
Surface Area ◽  
Aquatic Plant ◽  
Aquatic Macrophyte ◽  
Unit Surface Area ◽  
Artificial Wetlands ◽  
Polluted River ◽  
Plant System ◽  
Unit Surface ◽  
Experimental Facilities

Water purification using artificial wetlands and aquatic macrophyte is attracting attention as a purification technology that can create rich ecosystems while imposing a minimal load on the environment. Because an aquatic plant system requires a large surface area, design specifications and maintenance methods that can obtain the optimum purification effect per unit surface area must be established. Large experimental facilities have been constructed beside a polluted river flowing into Lake Kasumigaura and have been used for a three-year experiment using several kinds of aquatic plants. This report summarizes the characteristics and the design load of the aquatic plant system based on this study and results from other aquatic plant facilities.

scholarly journals The kinetics of influenza-virus adsorption on iron oxide in the process of viral purification and concentration

1971 ◽  
Vol 69 (1) ◽  
pp. 27-33 ◽  
Author(s):  
N. M. Larin ◽  
P. H. Gallimore
Keyword(s):  
Iron Oxide ◽  
Surface Area ◽  
Influenza A ◽  
Large Scale ◽  
Multiple Equilibria ◽  
Unit Surface Area ◽  
Fixed Temperature ◽  
Virus Adsorption ◽  
Significant Difference ◽  
Unit Surface

SUMMARYThis paper reports a study carried out to clarify the mechanisms involved in adsorption of influenza A and B viruses on iron oxide. Accordingly, the amounts of virus that are adsorbed from virus suspensions of varying concentrations per unit surface area of magnetic or non-magnetic oxide at fixed temperature and time have been determined. The principles involved are clearly the same as those involved in multiple equilibria during the interaction of particles with a large number of combining sites with different intrinsic affinity. Consequently, the amount of virus that is adsorbed per unit mass of iron oxide depends on the size of the adsorbent area, not on its magnetic property. Owing to a significant difference between the affinities of influenza A and B particles for the binding sites on iron oxide, unit surface area of the adsorbent is invariably capable of adsorbing significantly greater amounts of influenza A than B particles. The practical implications of these findings are that a better understanding of the mechanisms involved in virus adsorption on iron oxide will permit a more efficient separation of virus particles from impurities. The simplicity and the rapidity of the technique and the cheapness of the equipment required suggest that the iron oxide method is of great value for both small- or large-scale viral purification, whether it is used as a single step procedure or as a primary step followed by zonal separation.

scholarly journals Beç Tavuklarında (Numida meleagris) Yumurta Şekil İndeksinin Yumurta Kalitesine Etkileri

2016 ◽  
Vol 4 (9) ◽  
pp. 758 ◽  
Author(s):  
Sezai Alkan ◽  
Taki Karslı ◽  
İsmail Durmuş ◽  
Kemal Karabağ
Keyword(s):  
Surface Area ◽  
Egg Quality ◽  
Shape Index ◽  
Quality Characteristics ◽  
Unit Surface Area ◽  
Egg Volume ◽  
Egg Weight ◽  
Egg Shape ◽  
Unit Surface ◽  
Haugh Unit

The aim of this study was to investigated the effects of the egg shape index on egg quality characteristics in Guinea fowl. For this, the eggs were classified in terms of egg shape index, as ≤ 75, < 76 -77 > and ≥ 78. A total of 100 Guinea fowl eggs were evaluated to determine the egg quality traits ( egg weight, eggshell thickness, eggshell surface area, eggshell weight per unit surface area, eggshell ratio, albumen index, albumen ratio, yolk index, yolk ratio, yolk/albumen ratio, haugh unit and egg volume). In this study, eggshell thickness, eggshell weight per unit surface area, eggshell ratio, albumen index, albumen ratio, yolk index, yolk ratio, yolk/albumen ratio and haugh unit were not significantly affected by egg shape index groups. Whereas egg weight, eggshell surface area and egg volume were significantly affected by egg shape index groups. At the same time, there were found significant relationship between the egg shape index and egg quality traits. Egg shape index was found to be an important factor affecting the egg quality characteristics.

scholarly journals Spatial Statistics of the Sea Surface in Fetch-Limited Conditions

2011 ◽  
Vol 41 (10) ◽  
pp. 1821-1841 ◽  
Author(s):  
Leonel Romero ◽  
W. Kendall Melville
Keyword(s):  
Surface Area ◽  
Spatial Information ◽  
Length Distribution ◽  
Second Order ◽  
Joint Probability Distribution ◽  
Unit Surface Area ◽  
Large Wave ◽  
Analytical Approximations ◽  
Unit Surface ◽  
Wave Heights

Abstract An analysis of airborne wave observations collected in the Gulf of Tehuantepec is presented. The data include lidar measurements of the surface displacement as a function of two horizontal dimensions in fetch-limited conditions, with fetches between 20 and 500 km and winds between 10 and 20 m s−1. The spatial data have an advantage over the commonly used single-point time series measurements, allowing direct estimates of the wavelength and wave slope, including spatial information such as the lengths of crests exceeding various thresholds. This study presents an analysis of several statistical wind wave parameters, including the joint probability distribution function (pdf) of wave amplitudes and wavelengths; the pdf of wave heights, wavenumber vectors, and wave slopes; as well as the statistics of the lengths of crests exceeding threshold wave heights and slopes. The empirical findings from the lidar data are compared against analytical theories in the literature, including some that had not been tested previously with field data such as the work by M. S. Longuet-Higgins describing the length of contours surrounding large wave heights per unit surface area. The effect of second-order nonlinearities on the distribution of crest lengths per unit surface area is investigated with analytical approximations and stochastic numerical simulations from computed directional wavenumber spectra. The results show that second-order nonlinearities can increase the crest-length distribution of large waves by a factor of 2 or more.

Inhomogeneity of ventilatory unit volume and its effects on reactive gas uptake

1991 ◽  
Vol 70 (5) ◽  
pp. 2193-2205 ◽  
Author(s):  
R. R. Mercer ◽  
S. Anjilvel ◽  
F. J. Miller ◽  
J. D. Crapo
Keyword(s):  
Oxygen Uptake ◽  
Surface Area ◽  
Unit Volume ◽  
Unit Surface Area ◽  
Vascular Perfusion ◽  
Gas Uptake ◽  
Unit Surface ◽  
Reactive Gases ◽  
Gas Volume ◽  
Reactive Gas

This study addressed the question of whether variations in the volume of alveoli and alveolar ducts forming single units of ventilation can significantly influence the distribution and uptake of inspired reactive gases. Quantitative serial section analyses of vascular perfusion-fixed rat lungs were used to determine the anatomic dead space proximal to specific ventilatory units as well as the gas volume of these ventilatory units. Three reconstructions, each consisting of ventilatory units distal to a specific bronchus, were carried out. The number of ventilatory units for each reconstruction varied from 26 to 71. The average ventilatory unit volume for the three reconstructions [0.53 +/- .03 (SE) mm3] was not significantly different from measurements based on random sampling. The distribution of ventilatory unit volume was diverse, with 15% of the population having a volume less than 0.3 mm3 and 9% of the population having a volume greater than 1.0 mm3. For a gas of relatively low reactivity (e.g., oxygen) the predicted oxygen uptake per unit surface area did not vary significantly between ventilatory units. The predicted oxygen uptake was approximately 92% of the uptake in the absence of gradients in oxygen concentration between ventilatory units. For a highly reactive gas (e.g., ozone), the predicted uptake per unit surface area in the proximal portions of larger ventilatory units was significantly greater than the average uptake. These results suggest that focal areas of injury likely result from exposure to inhaled reactive gases.

Integrated Microchannel Cooling for Three-Dimensional Electronic Circuit Architectures

2005 ◽  
Vol 127 (1) ◽  
pp. 49-58 ◽  
Author(s):  
Jae-Mo Koo ◽  
Sungjun Im ◽  
Linan Jiang ◽  
Kenneth E. Goodson
Keyword(s):  
Surface Area ◽  
Microelectromechanical Systems ◽  
Signal Transmission ◽  
Three Dimensional ◽  
Unit Surface Area ◽  
One Dimensional ◽  
Unit Surface ◽  
3D Architecture ◽  
Past Data ◽  
Microchannel Cooling

The semiconductor community is developing three-dimensional circuits that integrate logic, memory, optoelectronic and radio-frequency devices, and microelectromechanical systems. These three-dimensional (3D) circuits pose important challenges for thermal management due to the increasing heat load per unit surface area. This paper theoretically studies 3D circuit cooling by means of an integrated microchannel network. Predictions are based on thermal models solving one-dimensional conservation equations for boiling convection along microchannels, and are consistent with past data obtained from straight channels. The model is combined within a thermal resistance network to predict temperature distributions in logic and memory. The calculations indicate that a layer of integrated microchannel cooling can remove heat densities up to 135W/cm2 within a 3D architecture with a maximum circuit temperature of 85°C. The cooling strategy described in this paper will enable 3D circuits to include greater numbers of active levels while exposing external surface area for functional signal transmission.

scholarly journals Interferon effects on microfilament organization cellular fibronectin distribution, and cell motility in human fibroblasts

1980 ◽  
Vol 85 (1) ◽  
pp. 9-17 ◽  
Author(s):  
LM Pfeffer ◽  
E Wang ◽  
I Tamm
Keyword(s):  
Cell Surface ◽  
Surface Area ◽  
Human Fibroblasts ◽  
Unit Surface Area ◽  
Interferon Treatment ◽  
Membrane Ruffling ◽  
Control Value ◽  
Unit Surface ◽  
10 Nm Filaments ◽  
Parallel Arrays

We have shown previously (Pfeffer et al., 1979, Exp. Cell Res. 121:111-120) that treatment of human fibroblasts, planted at a density of 2x10(3) cells/cm(2), with purified human fibroblasts interferon (640 U/ml) for 3 d at 37 degrees C decreases the overall rate of cell proliferation to 35-40 percent of the control value. In the present experiments we have characterized the phenotype of interferon-inhibited fibroblasts. The mean volume of trypsinized, interferon-treated cells was increased 31 percent abover that of control cells. The interferon-treated population was much more heterogeneous than the control population with respect to volume, and there was a considerable overlap in the volume distributions of the two populations. The cell surface area was, on the average, increased 65 percent after interferon treatment. More than 80 percent of the treated cells had enlarged nuclei, many of which were lobed, and the fraction of binucleated cells was increased fivefold. After interferon treatment, over 40 percent of the cells showed large actin-containing fibers in the form of multiple parallel arrays. Fewer than 5 percent of the control cells contained such large actin fibers. The number of actin fibers of all sizes was tripled in the treated fibroblasts on a per cell basis and, calculated per unit surface area of the cells, the number was increased 82 percent. In contrast, 10-nm filaments and microtubules did not appear to be increased in number per unit surface area of the cells. The increases per cell in the abundance of these structures were directly related to increased cell size. After interferon treatment, fibronection was distributed in arrays of long filaments covering most portions of the cell surface. Interferon treatment markedly decreased the rate of cell locomotion as well as membrane ruffling and saltatory movements of intracellular granules.

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