Relative rate of change of a function

1999 ◽  
Vol 35 (4) ◽  
pp. 653-657 ◽  
Author(s):  
V. Yu. Kotlyar
Keyword(s):  
Genetics ◽  
1996 ◽  
Vol 144 (4) ◽  
pp. 1961-1974 ◽  
Author(s):  
Ming Wei ◽  
Armando Caballero ◽  
William G Hill

Formulae were derived to predict genetic response under various selection schemes assuming an infinitesimal model. Account was taken of genetic drift, gametic (linkage) disequilibrium (Bulmer effect), inbreeding depression, common environmental variance, and both initial segregating variance within families (σAW02) and mutational (σM2) variance. The cumulative response to selection until generation t(CRt) can be approximated asCRt≈R0[t−β(1−σAW∞2σAW02)t24Ne]−Dt2Ne,where Ne is the effective population size, σAW∞2=NeσM2 is the genetic variance within families at the steady state (or one-half the genic variance, which is unaffected by selection), and D is the inbreeding depression per unit of inbreeding. R  0 is the selection response at generation 0 assuming preselection so that the linkage disequilibrium effect has stabilized. β is the derivative of the logarithm of the asymptotic response with respect to the logarithm of the within-family genetic variance, i.e., their relative rate of change. R  0 is the major determinant of the short term selection response, but σM2, Ne and β are also important for the long term. A selection method of high accuracy using family information gives a small Ne and will lead to a larger response in the short term and a smaller response in the long term, utilizing mutation less efficiently.


1985 ◽  
Vol 248 (6) ◽  
pp. E656-E663 ◽  
Author(s):  
D. E. Peavy ◽  
J. M. Taylor ◽  
L. S. Jefferson

Albumin synthesis in rat liver in vivo decreased from 12.7 to 2.2% of total protein synthesis during the first 3 days after the induction of diabetes and then remained relatively constant at this depressed rate for another 3 days. Insulin treatment begun on the 3rd day after the induction of diabetes restored albumin synthesis to control values within 3 days. Hybridization of total polyadenylate-containing RNA with a specific albumin cDNA probe revealed a close correspondence between the relative abundance of albumin mRNA and the relative rate of albumin synthesis after induction of diabetes and in response to insulin treatment. The apparent half-life of albumin mRNA, based on the rate of change of the message from one steady-state level to another, was approximately 22 h in both diabetic and insulin-treated diabetic rats. Diabetes of 3-day duration had no effect on the average sizes of total and albumin-synthesizing polysomes or on the ribosomal half-transit time for total protein and albumin. However, the number of albumin-synthesizing polysomes decreased as a result of diabetes to approximately one-third the number found in control livers. Taken together the results indicate that albumin synthesis was regulated by the availability of albumin mRNA and not by alterations in degradation, sequestration, or translation of message.


2020 ◽  
Vol 39 (21) ◽  
pp. 2695-2713
Author(s):  
Marcela I. Cespedes ◽  
James M. McGree ◽  
Christopher C. Drovandi ◽  
Kerrie Mengersen ◽  
Jurgen Fripp ◽  
...  

2020 ◽  
Author(s):  
Joao Manoel Losada Moreira

Managing the COVID-19 pandemic in the middle of the events requires real-time monitoring of its evolution to perform analyses of containment actions and to project near future scenarios. This work proposes a scheme to monitor the temporal evolution of the COVID-19 pandemic using the time series of its total number of confirmed cases in a given region. The monitored parameter is the spread rate obtained from this time series (day-1) expressed in %/day. The scheme's capability is verified using the epidemic data from China and South Korea. Its projection capability is shown for Italy and United States with scenarios for the ensuing 30 days from April 2nd, 2020. The spread rate (relative rate of change of the time series) is very sensitive to sudden changes in the epidemic evolution and can be used to monitor in real-time the effectiveness of containment actions. The logarithm of this variable allows identifying clear trends of the evolution of the COVID-10 epidemic in these countries. The spread rate calculated from the number of confirmed cases of infection is interpreted as a probability per unit of time of virus infection and containment actions. Its product with the number of confirmed cases of infections yields the number of new cases per day. The stabilization and control of the epidemic for China and South Korea appear to occur for values of this parameter below 0.77 %/day (doubling time of 90 days).


2020 ◽  
pp. 089033442096363
Author(s):  
M. Elizabeth Gyllstrom ◽  
Marcia Burton McCoy ◽  
Gianfranco Pezzini ◽  
Adam Atherly

Background Cross-jurisdictional sharing is gaining traction as an option for increasing the effectiveness and efficiency of public health services in local health departments. Research aim Assess whether breastfeeding initiation among participants in the Special Supplemental Nutrition Program for Women, Infants and Children changed with the addition of a trained breastfeeding specialist funded by cross-jurisdictional integration. Methods A longitudinal retrospective comparative difference in difference design using state-based program data, pre- and post-integration was undertaken. Three local county health departments ( n = 5) that fully integrated into one Community Health Board during January 2015, and four neighboring Community Health Boards ( n = 4) that did not integrate, were included. Results Controlling for confounders and interactions, the relative rate of change over time in breastfeeding initiation rates was greater in the integrated jurisdiction than neighboring Community Health Boards, but not statistically significant. When the integrated Community Health Board’s original three local health departments were considered separately, the relative rate of change over time in breastfeeding rates was greater for one local health department in comparison to three neighbor Community Health Boards ( p = .037, .048, and .034, respectively). Conclusions The addition of a specialized breastfeeding nutritionist led to improved breastfeeding initiation rates. The increase was significant only in the largest original local health department, which also had the lowest breastfeeding initiation rate pre-merger. The greatest positive change was seen in this local health department where the specialist staff was physically located. Public health staff specialization can lead to increases in economic efficiency and in improved delivery of public health services.


2004 ◽  
Vol 467-470 ◽  
pp. 1111-1116 ◽  
Author(s):  
Lasar S. Shvindlerman ◽  
Günter Gottstein ◽  
Anthony D. Rollett

We present a new analysis of the relative rate of growth or shrinkage of grains in a two-dimensional network, based on the classical Von Neumann-Mullins (VN-M) analysis. We find that an analysis of the stability of the grain shape during shrinkage or growth shows that any change in the regular 2D grain leads to changes in the shape. We also re-examine a recent analysis that claims to have invalidated the VN-M relationship, but find that it is still valid, and that the cited analysis, in fact, confused a second order correction with a first order problem, partly because their derivation was in error. The erroneous magnitude of the discrepancy led them to use unphysical issues to explain the discrepancy. The way in which the curvature is distributed along the perimeter of a grain only gives rise only to second order corrections to the rate of change of area as a function of grain topology (number of sides).


1993 ◽  
Vol 11 (4) ◽  
pp. 679-684
Author(s):  
Nikolai E. Tsapenko

In this article, we derived new formulas for approximate representation of components of a plane electromagnetic wave in heterogeneous medium that has parameters changing along some fixed direction in an arbitrary manner. The formulas differ from ordinary WKB approximation by factors regarding relative rate of medium characteristics change and give solutions remaining continuous at turning points. Conditions of full opaque and of no reflectionbased on the solution are obtained.


2017 ◽  
Author(s):  
David N. Lee ◽  
Apostolos P. Georgopoulos ◽  
Gert-Jan Pepping

AbstractNervous systems control purposeful movement, both within and outside the body, which is essential for the survival of an animal. The movement control functions of globus pallidus (GP), subthalamic nucleus (STN) and zona incerta (ZI) were analyzed in monkeys reaching for seen targets. Temporal profiles of the hand movements of monkeys and the synchronized flow of electrochemical energy through these basal ganglia were analyzed in terms of a theory of goal-directed movement. Theoretical and empirical analysis indicated: (i) the neural information for controlling movement is the relative-rate-of-change of flow of electrochemical energy in neurons rather than the flow itself; (ii) GP is involved in creating prospective electrochemical flow to guide movement; (iii) STN is involved in registering the perceptual electrochemical flow monitoring the movement; (iv) ZI is involved in integrating the prospective and perceptual electrochemical flows to power the muscles and thence the movement. Possible implications for PD are discussed.


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