Evaluation of the Multiplication Rate of Human Cancer through the Study of Growth Diagrams

1966 ◽  
Vol 52 (4) ◽  
pp. 247-276
Author(s):  
Sergio Massenti ◽  
Lionello Michelassi ◽  
Lamberto Venturoli
Keyword(s):  
Growth Models ◽  
Human Cancer ◽  
Multiplication Rate ◽  
Biological Factors ◽  
Neoplastic Cells ◽  
Biological Reality ◽  
Irradiation Therapy ◽  
Cellular Population ◽  
The Waves

The determination of growth rates in human tumors is studied through growth diagrams obtained with radiographic or direct measurement (made several times) from the diameters of round neoplastic nodes. The mathematic development of two different growth models, one, more common, based on the dimensional increase of tumor dependent from the dual fission of all the neoplastic cells, the second based on the intervention of biological factors, which reduce, variously at different times, the quota of the cellular population active for reproduction, showed different «periods of reproduction». A third system to ascertain the « period of reproduction » of a neoplastic cells population, is based on the study of the diagrams concerned with the variation in time of the growth rate ∊: owing to the rhythm of the waves it is probable that these are dependent from the predominant phase of the cellular cycle at the time the cellular population is examined. It is suggested that it would be more realistic and closed to the biological reality to obtain the value on the « periods of reproduction » through the last two systems, the mathematic and graphic analyses of which are presented. These studies may give the basic biometrical values necessary for the planning of fractionation of irradiation therapy according to the neoplastic cellular cycle.

Polarographic and spectrophotometric behaviour of some N-p-phenyl substituted benzamidines

1991 ◽  
Vol 56 (12) ◽  
pp. 2791-2799 ◽  
Author(s):  
Juan A. Squella ◽  
Luis J. Nuñez-Vergara ◽  
Hernan Rodríguez ◽  
Amelia Márquez ◽  
Jose M. Rodríguez-Mellado ◽  
...  
Keyword(s):  
Spectrophotometric Study ◽  
Absorption Bands ◽  
Electrochemical Parameters ◽  
Wide Ph Range ◽  
Group A ◽  
Substituent Constants ◽  
Ph Range ◽  
The Waves

Five N-p-phenyl substituted benzamidines were studied by DC and DP polarography in a wide pH range. Coulometric results show that the overall processes are four-electron reductions. Logarithmic analysis of the waves indicate that the process are irreversible. The influence of the pH on the polarographic parameters was also studied. A UV spectrophotometric study was performed in the pH range 2-13. In basic media some variations in the absorption bands were observed due to the dissociation of the amidine group. A determination of the pK values was made by deconvolution of the spectra. Correlations of both the electrochemical parameters and spectrophotometric pK values with the Hammett substituent constants were obtained.

Near earthquakes in Central California*

1939 ◽  
Vol 29 (3) ◽  
pp. 427-462 ◽  
Author(s):  
Perry Byerly
Keyword(s):  
Least Squares ◽  
Travel Time ◽  
Sierra Nevada ◽  
Accurate Determination ◽  
Depth Of Focus ◽  
Surface Layers ◽  
P Waves ◽  
Central California ◽  
The Waves

Summary Least-squares adjustments of observations of waves of the P groups at central and southern California stations are used to obtain the speeds of various waves. Only observations made to tenths of a second are used. It is assumed that the waves have a common velocity for all earthquakes. But the time intercepts of the travel-time curves are allowed to be different for different shocks. The speed of P̄ is found to be 5.61 km/sec.±0.05. The speed for S̄ (founded on fewer data) is 3.26 km/sec. ± 0.09. There are slight differences in the epicenters located by the use of P̄ and S̄ which may or may not be significant. It is suggested that P̄ and S̄ may be released from different foci. The speed of Pn, the wave in the top of the mantle, is 8.02 km/sec. ± 0.05. Intermediate P waves of speeds 6.72 km/sec. ± 0.02 and 7.24 km/sec. ± 0.04 are observed. Only the former has a time intercept which allows a consistent computation of structure when considered a layer wave. For the Berkeley earthquake of March 8, 1937, the accurate determination of depth of focus was possible. This enabled a determination of layering of the earth's crust. The result was about 9 km. of granite over 23 km. of a medium of speed 6.72 km/sec. Underneath these two layers is the mantle of speed 8.02 km/sec. The data from other shocks centering south of Berkeley would not fit this structure, but an assumption of the thickening of the granite southerly brought all into agreement. The earthquakes discussed show a lag of Pn as it passes under the Sierra Nevada. This has been observed before. A reconsideration of the Pn data of the Nevada earthquake of December 20, 1932, together with the data mentioned above, leads to the conclusion that the root of the mountain mass projects into the mantle beneath the surface layers by an amount between 6 and 41 km.

scholarly journals MODELING OF STRUCTURES SUBJECTED TO WIND GENERATED WAVES

1968 ◽  
Vol 1 (11) ◽  
pp. 48
Author(s):  
Erich J. Plate ◽  
John H. Nath
Keyword(s):  
Modulus Of Elasticity ◽  
Direct Determination ◽  
Model Material ◽  
Water Tunnel ◽  
State University ◽  
Colorado State University ◽  
The Waves

The difficulties inherent in the direct determination of loads on off-shore structures which are exposed simultaneously to wind and waves make it desirable to model each situation in the laboratory It is shown here that scaling of the loads and the waves is possible by using waves which are generated by blowing air over the surface of a laboratory channel, and by choosing a model material with an appropriate modulus of elasticity Wind-generated waves such as those measured m the wind water tunnel of Colorado State University have a dimensionless spectrum (Hidy and Plate (1965)) that is identical in shape to that found off the coast of Florida under hurricane conditions (Collins (1966)) Furthermore, it has been shown that hydro-elastic modeling is quite feasible (LeMehaute (1966)) These two results are combined to give modeling criteria for off-shore structures if direct wind forces are disregarded.

Biological factors and the determination of androgens in female subjects

Steroids ◽  
2008 ◽  
Vol 73 (12) ◽  
pp. 1203-1216 ◽  
Author(s):  
C. Enea ◽  
N. Boisseau ◽  
V. Diaz ◽  
B. Dugué
Keyword(s):  
Biological Factors ◽  
Female Subjects

Growth of Grey Kangaroos and the Reliablility of Age Determination from Body Measurements III. Interspecific Comparisions between Eastern and Western Grey Kangaroos, Macropus giganteus and M. fuliginosus

1984 ◽  
Vol 11 (1) ◽  
pp. 11 ◽  
Author(s):  
WE Poole ◽  
SM Carpenter ◽  
JT Wood
Keyword(s):  
Growth Models ◽  
Age Determination ◽  
Growth Patterns ◽  
Adult Size ◽  
Body Measurements ◽  
Foot Length ◽  
The Common ◽  
Rates Of Growth ◽  
Body Parameters

Seven body measurements were taken at regular intervals throughout life from both male and female eastern and western grey kangaroos. Evaluation of the reliability of criteria for determination of age and some aspects of the growth models for the two species were presented in earlier papers in this series. In this paper the common patterns and relationships between species in the growth characteristics of their body parameters are described and analysed. Comparison is made between species and sexes of rates of growth and size attained both within the pouch and following vacation of the pouch. Head, arm, leg and foot length were important discriminators, particularly when contrasted in various ways to summarize different body proportions. The insular form M.f. fuliginosus readily separated from the mainland forms, and M.f. ocydromus showed some differences which were related to its longer pouch life. Hybrid animals showed growth patterns intermediate to those of their parents. Sexual dimorphism in patterns ofgrowth was not detected during pouch life but was exhibited by all species after the young vacated the pouch and grew towards their full adult size.

scholarly journals Determination of coupled sway, roll, and yaw motions of a floating body in regular waves

2004 ◽  
Vol 2004 (41) ◽  
pp. 2181-2197 ◽  
Author(s):  
S. N. Das ◽  
S. K. Das
Keyword(s):  
Dynamic Equilibrium ◽  
Numerical Models ◽  
Equations Of Motion ◽  
System Stability ◽  
Floating Body ◽  
Regular Waves ◽  
Laplace Transform Technique ◽  
Restoring Forces ◽  
The Waves

This paper investigates the motion response of a floating body in time domain under the influence of small amplitude regular waves. The governing equations of motion describing the balance of wave-exciting force with the inertial, damping, and restoring forces are transformed into frequency domain by applying Laplace transform technique. Assuming the floating body is initially at rest and the waves act perpendicular to the vessel of lateral symmetry, hydrodynamic coefficients were obtained in terms of integrated sectional added-mass, damping, and restoring coefficients, derived from Frank's close-fit curve. A numerical experiment on a vessel of19190ton displaced mass was carried out for three different wave frequencies, namely,0.56rad/s,0.74rad/s, and1.24rad/s. The damping parameters (ςi) reveal the system stability criteria, derived from the quartic analysis, corresponding to the undamped frequencies (βi). It is observed that the sway and yaw motions become maximum for frequency0.56rad/s, whereas roll motion is maximum for frequency0.74rad/s. All three motions show harmonic behavior and attain dynamic equilibrium for timet>100seconds. The mathematical approach presented here will be useful to determine seaworthiness characteristics of any vessel when wave amplitudes are small and also to validate complex numerical models.

scholarly journals Pulsation and Mass Loss in LPVs

1993 ◽  
Vol 139 ◽  
pp. 191-191
Author(s):  
George H. Bowen
Keyword(s):  
Mass Loss ◽  
Stellar Evolution ◽  
Loss Rate ◽  
Mass Loss Rate ◽  
Individual Stars ◽  
Rich Variety ◽  
Long Period ◽  
And Behavior ◽  
The Waves

AbstractThe large-amplitude pulsation of long-period variables, together with a number of other interacting processes and phenomena, causes a rich variety of effects on the structure and behavior of the stars. Outflowing winds result, causing extensive mass loss, with profound consequences for stellar evolution. The present status of modeling calculations for LPVs will be discussed first, with various examples. Emphasis will be given to the great importance of complex, nonlinear, time-dependent interactions between things such as the waves and atmospheric shocks that result from pulsation; non-LTE radiative transfer; non-equilibrium chemistry; the growth, changing optical properties, and dynamics of grains; and radiation pressure on both grains and molecules. I will then survey the developing implications and insights from new results and from work now in progress. Some of these concern the structure and the behavior of individual stars (e.g. determination of the pulsation mode and limiting amplitude; properties of more massive stars); some relate to the evolution of individual stars (e.g. evolution of the wind and the mass loss rate; the wind and circumstellar region during helium shell flashes; effects of the star's metallicity); and some relate to the evolution of populations of stars (e.g. the white dwarf mass distribution). All of these, and many more, offer new perspectives and new understanding concerning the character of LPVs and their role in stellar evolution.

The effect of a semi-contaminated free surface on mass transport

1974 ◽  
Vol 75 (2) ◽  
pp. 283-294 ◽  
Author(s):  
D. Porter ◽  
B. D. Dore
Keyword(s):  
Free Surface ◽  
Velocity Field ◽  
Mass Transport ◽  
Mixed Boundary ◽  
Surface Film ◽  
Vertical Displacement ◽  
Mass Transport Velocity ◽  
Harmonic Equation ◽  
The Waves

AbstractThe mass transport velocity field is determined for surface waves which propagate from a region with a clean free surface into a region beneath an inextensible surface film. The waves are assumed to be incident normally on the edge of the film. Determination of this velocity field requires the investigation of a mixed boundary value problem for the bi-harmonic equation, the solution of which is obtained using the Wiener–Hopf technique. Streamlines for the mean motion of the fluid particles are thus obtained. It is found that considerable vertical displacement of fluid is possible due to the presence of the surface film.

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