scholarly journals GENE CONVERSION AND TRANSFER OF GENETIC INFORMATION WITHIN THE INVERTED REGION OF INVERSION HETEROZYGOTES

Genetics ◽  
1973 ◽  
Vol 75 (1) ◽  
pp. 123-131
Author(s):  
Arthur Chovnick
Keyword(s):  
Information Transfer ◽  
Logical Consequence ◽  
Natural Populations ◽  
Inverted Region ◽  
Order Of Magnitude ◽  
Inversion Heterozygote ◽  
Gene Complexes ◽  
Reciprocal Transfer ◽  
Comparison Of The Results ◽  
Transfer Of Information

ABSTRACT Prior studies of recombination which monitor exchange events in exceedingly short intervals (i.e., separable sites within a cistron) reveal that the basic event in recombination involves a non-reciprocal transfer of information, termed conversion. As a logical consequence of the model suggested by the work in Drosophila, the present investigation examined recombination between rosy mutant alleles (ry:3-52.0) in Drosophila melanogaster in a paracentric inversion (In(3R)P18) heterozygote, which placed the rosy region approximately at the center of the inverted region. Comparison of the results of this study with experiments carried out in standard chromosome homozygotes reveals a dramatic suppression of classical crossovers between the rosy mutant alleles in the inversion heterozygote. However, conversions continue to occur for all rosy mutant alleles in all heterozygous combinations in the inversion heterozygote. Moreover, the order of magnitude of conversion frequencies seen in the inversion heterozygote does not change from that seen in the standard chromosome homozygote study. The significance of these observations with reference to the role of rearrangements as barriers of information transfer is discussed. Particular attention is directed to the elaborate inversion polymorphisms seen in natural populations, and to notions concerning their role in the evolution of adaptive gene complexes.

scholarly journals On the Rate and Linearity of Viability Declines in Drosophila Mutation-Accumulation Experiments: Genomic Mutation Rates and Synergistic Epistasis Revisited

Genetics ◽  
2004 ◽  
Vol 166 (2) ◽  
pp. 797-806 ◽  
Author(s):  
James D Fry
Keyword(s):  
Mutation Rate ◽  
Average Rate ◽  
Natural Populations ◽  
Mutation Accumulation ◽  
High Rate ◽  
Deleterious Mutations ◽  
Order Of Magnitude ◽  
Contamination Event ◽  
Genomic Mutation ◽  
The 1960S

Abstract High rates of deleterious mutations could severely reduce the fitness of populations, even endangering their persistence; these effects would be mitigated if mutations synergize each others’ effects. An experiment by Mukai in the 1960s gave evidence that in Drosophila melanogaster, viability-depressing mutations occur at the surprisingly high rate of around one per zygote and that the mutations interact synergistically. A later experiment by Ohnishi seemed to support the high mutation rate, but gave no evidence for synergistic epistasis. Both of these studies, however, were flawed by the lack of suitable controls for assessing viability declines of the mutation-accumulation (MA) lines. By comparing homozygous viability of the MA lines to simultaneously estimated heterozygous viability and using estimates of the dominance of mutations in the experiments, I estimate the viability declines relative to an appropriate control. This approach yields two unexpected conclusions. First, in Ohnishi’s experiment as well as in Mukai’s, MA lines showed faster-than-linear declines in viability, indicative of synergistic epistasis. Second, while Mukai’s estimate of the genomic mutation rate is supported, that from Ohnishi’s experiment is an order of magnitude lower. The different results of the experiments most likely resulted from differences in the starting genotypes; even within Mukai’s experiment, a subset of MA lines, which I argue probably resulted from a contamination event, showed much slower viability declines than did the majority of lines. Because different genotypes may show very different mutational behavior, only studies using many founding genotypes can determine the average rate and distribution of effects of mutations relevant to natural populations.

scholarly journals Precision Annealing Monte Carlo Methods for Statistical Data Assimilation: Metropolis-Hastings Procedures

2019 ◽  
Author(s):  
Adrian S. Wong ◽  
Kangbo Hao ◽  
Zheng Fang ◽  
Henry D. I. Abarbanel
Keyword(s):  
Monte Carlo ◽  
Probability Distribution ◽  
Data Assimilation ◽  
Conditional Probability ◽  
Information Transfer ◽  
Statistical Data ◽  
Laplace Method ◽  
Conditional Probability Distribution ◽  
Expected Values ◽  
Transfer Of Information

Abstract. Statistical Data Assimilation (SDA) is the transfer of information from field or laboratory observations to a user selected model of the dynamical system producing those observations. The data is noisy and the model has errors; the information transfer addresses properties of the conditional probability distribution of the states of the model conditioned on the observations. The quantities of interest in SDA are the conditional expected values of functions of the model state, and these require the approximate evaluation of high dimensional integrals. We introduce a conditional probability distribution and use the Laplace method with annealing to identify the maxima of the conditional probability distribution. The annealing method slowly increases the precision term of the model as it enters the Laplace method. In this paper, we extend the idea of precision annealing (PA) to Monte Carlo calculations of conditional expected values using Metropolis-Hastings methods.

It's Not My Fault

2019 ◽  
Vol 30 (3) ◽  
pp. 18-37
Author(s):  
Tawei Wang ◽  
Yen-Yao Wang ◽  
Ju-Chun Yen
Keyword(s):  
Information Security ◽  
Information Transfer ◽  
Large Data ◽  
Future Research ◽  
Data Set ◽  
Security Breach ◽  
Security Breaches ◽  
Personally Identifiable Information ◽  
Types Of Information ◽  
Transfer Of Information

This article investigates the transfer of information security breach information between breached firms and their peers. Using a large data set of information security incidents from 2003 to 2013, the results suggest that 1) the effect of information security breach information transfer exists between breached firms and non-breached firms that offer similar products and 2) the effect of information transfer is weaker when the information security breach is due to internal faults or is related to the loss of personally identifiable information. Additional tests demonstrate that the effect of information transfer exhibits consistent patterns across time and with different types of information security breaches. Finally, the effect does not depend on whether the firms are IT intensive. Implications, limitations, and future research are discussed.

INFORMATION TRANSFER IN THE GENERALIZED SYNCHRONIZATION

2011 ◽  
Vol 25 (19) ◽  
pp. 2575-2582
Author(s):  
MOGEI WANG ◽  
XINGYUAN WANG ◽  
ZHENZHEN LIU
Keyword(s):  
Lyapunov Exponent ◽  
Symbolic Dynamics ◽  
Information Transfer ◽  
Generalized Synchronization ◽  
New Meanings ◽  
Response State ◽  
Transfer Of Information ◽  
And Storage

We use symbolic dynamics to investigate the transfer of information between the dissipative coupled nonidentical oscillators exhibiting the generalized synchronization. It is found that the drive information is injected into the response state and stored reversely in it. Moreover, the injection and storage give new meanings to the conditional Lyapunov exponent from the view of the information.

Insertional polymorphism of a non-LTR mobile element (NLRCth1) in European populations of Chironomus riparius (Diptera, Chironomidae) as detected by transposon insertion display

Genome ◽  
2004 ◽  
Vol 47 (6) ◽  
pp. 1154-1163 ◽  
Author(s):  
G Zampicinini ◽  
A Blinov ◽  
P Cervella ◽  
V Guryev ◽  
G Sella
Keyword(s):  
Natural Populations ◽  
Mobile Element ◽  
Genetic Distances ◽  
Chironomus Riparius ◽  
Allozyme Polymorphism ◽  
Transposon Insertion ◽  
Random Samples ◽  
Order Of Magnitude ◽  
Specific Amplification ◽  
Insertional Polymorphism

The midge Chironomus riparius is distributed all over the Palearctic region and is well characterized both at the morphological and cytogenetic levels. Here we describe a population study based on the insertional polymorphism of the retroposon NLRCth1, by means of a S-SAP (sequence-specific amplification polymorphism) derived technique (transposon insertion display; TID). While a previous study of allozyme polymorphism in Russian samples showed little variability, all the amplicons we identified are polymorphic. Genetic distances between 6 natural populations were calculated according to Nei and did not show a positive correlation with geographic distances. The genetic diversity detected among individuals of a given population was one order of magnitude higher than that among populations. However, the value of ΦST was significant (p < 0.001) and indicates that natural populations are more genetically differentiated than random samples of individuals.Key words: retrotransposable elements, genetic differentiation, Chironomus riparius, sequence-specific amplification polymorphism.

scholarly journals Phenotypic assortment in wild primate networks: implications for the dissemination of information

2015 ◽  
Vol 2 (5) ◽  
pp. 140444 ◽  
Author(s):  
Alecia J. Carter ◽  
Alexander E. G. Lee ◽  
Harry H. Marshall ◽  
Miquel Torrents Ticó ◽  
Guy Cowlishaw
Keyword(s):  
Social Networks ◽  
Information Flow ◽  
Information Transfer ◽  
Dominance Rank ◽  
Phenotypic Traits ◽  
Considerable Variability ◽  
Papio Ursinus ◽  
Phenotypic Assortment ◽  
Using Data ◽  
Transfer Of Information

Individuals' access to social information can depend on their social network. Homophily—a preference to associate with similar phenotypes—may cause assortment within social networks that could preclude information transfer from individuals who generate information to those who would benefit from acquiring it. Thus, understanding phenotypic assortment may lead to a greater understanding of the factors that could limit the transfer of information between individuals. We tested whether there was assortment in wild baboon ( Papio ursinus ) networks, using data collected from two troops over 6 years for six phenotypic traits—boldness, age, dominance rank, sex and the propensity to generate/exploit information—using two methods for defining a connection between individuals—time spent in proximity and grooming. Our analysis indicated that assortment was more common in grooming than proximity networks. In general, there was homophily for boldness, age, rank and the propensity to both generate and exploit information, but heterophily for sex. However, there was considerable variability both between troops and years. The patterns of homophily we observed for these phenotypes may impede information transfer between them. However, the inconsistency in the strength of assortment between troops and years suggests that the limitations to information flow may be quite variable.

scholarly journals Signalling: basics and evolution.

2004 ◽  
Vol 51 (2) ◽  
pp. 281-298 ◽  
Author(s):  
Robert J P Williams
Keyword(s):  
Dna Sequence ◽  
Cell Biology ◽  
Information Transfer ◽  
Cellular Activity ◽  
Stimulate Activity ◽  
General Metabolism ◽  
A Cell ◽  
Transfer Of Information ◽  
The Brain ◽  
Source Of Information

Signalling concerns the transfer of information from one body, a source, to another, a receiver in order to stimulate activity. The problem arises with the word information. It is defined as what is transferred in a sequence of things, say between people, e.g. words or signs. The idea of signalling between people is then obvious but it is not clear in cell biology. Information transfer, signalling, is required for the organisation of all cellular activity but we must ask what is transferred and how is it transmitted and received? Sometimes it is assumed that all information, i.e. organisation in a cell, is represented in the DNA sequence. This is incorrect. We shall show that the environment is a second source of information concerning material and energy. The receiving party from both DNA and the environment is general metabolism. The metabolism then signals back and sends information to both DNA and uptake from the environment. Even then energy is needed with machinery to send out all signals. This paper examines the way signalling evolved from prokaryotes through to man. In this process the environmental information received increased to the extent that finally the brain is a phenotypic as much as a genotypic organ within a whole organism. By phenotypic we mean it is organised by and interactive with information from the environment.

scholarly journals Pitfalls in the Assessment of Brain-Machine Interfaces Using Information Transfer Rate

2017 ◽  
Author(s):  
Mikhail A. Lebedev ◽  
Po-He Tseng ◽  
Peter J. Ifft ◽  
Dennis Ochei ◽  
Miguel A.L. Nicolelis
Keyword(s):  
Motor Performance ◽  
Transfer Rate ◽  
Information Transfer ◽  
List Type ◽  
Brain Machine Interfaces ◽  
Practical Applications ◽  
Information Transfer Rate ◽  
Recording Channels ◽  
Transfer Of Information

AbstractInformation transfer rate (ITR), measured in bits/s, can be applied to evaluate motor performance, including the capacity of brain-machine interfaces (BMIs) to control external actuators. In a 2013 article entitled “Transfer of information by BMI” and published in Neuroscience, Tehovnik and his colleagues utilized ITR to assess the performance of several BMIs reported in the literature. We examined these analyses closely and found several fundamental flaws in their evaluation of ITR. Here we discuss the pitfalls in Tehovnik’s measurements of ITR, as well as several other issues raised in “Transfer of information by BMI”, including the claim that BMIs cannot be a reasonable option for paralyzed patients.HighlightsInformation transfer rate is discussed for BMI experiments, where subjects reach to targets.Task settings, not just the number of possible targets, are important to calculate information correctly.Active tactile exploration can be quantified as information transfer, but the number of targets is insufficient for such quantification.Information transfer rate increases with the number of neural recording channels.For practical applications, improvement in quality of life is essential, not information transfer rate per se.

scholarly journals Transfer entropy and cumulant based cost as measures of nonlinear causal relationships in space plasmas: applications to <i>D<sub><i>st</i></i>

2018 ◽  
Author(s):  
Jay R. Johnson ◽  
Simon Wing ◽  
Enrico Camporeale
Keyword(s):  
Solar Wind ◽  
Mutual Information ◽  
Strong Correlation ◽  
Information Transfer ◽  
Ring Current ◽  
Space Physics ◽  
Transfer Entropy ◽  
Linear Relationships ◽  
Transfer Of Information

Abstract. It is well known that the magnetospheric response to the solar wind is nonlinear. Information theoretical tools such as mutual information, transfer entropy, and cumulant based analysis are able to characterize the nonlinearities in the system. Using cumulant based cost, we show that nonlinear significance of Dst peaks at 3–12 hours lags that can be attributed to VBs which also exhibit similar behavior. However, the nonlinear significance that peaks at lags 25, 50, and 90 hours can be attributed to internal dynamics, which may be related to the relaxation of the ring current. These peaks are absent in the linear and nonlinear self-significance of VBs. Our analysis with mutual information and transfer entropy show that both methods can establish that there are a strong correlation and transfer of information from Vsw to Dst at a time scale that is consistent with that obtained from the cumulant based analysis. However, mutual information also shows that there is a strong correlation in the backward direction, from Dst to Vsw, which is counterintuitive. In contrast, transfer entropy shows that there is no or little transfer of information from Dst to Vsw, as expected because it is the solar wind that drives the magnetosphere, not the other way around. Our case study demonstrates that these information theoretical tools are quite useful for space physics studies because these tools can uncover nonlinear dynamics that cannot be seen with the traditional analyses and models that assume linear relationships.

scholarly journals THE EFFECT OF COMBINING ALLELES INTO ELECTROPHORETIC CLASSES ON DETECTING LINKAGE DISEQUILIBRIUM

Genetics ◽  
1977 ◽  
Vol 85 (3) ◽  
pp. 543-556
Author(s):  
E Zouros ◽  
G B Golding ◽  
Trudy F C MacKay
Keyword(s):  
Linkage Disequilibrium ◽  
Sample Size ◽  
Natural Populations ◽  
Epistatic Interactions ◽  
Detection Power ◽  
Linkage Disequilibria ◽  
Allelic Distribution ◽  
Order Of Magnitude ◽  
Actual Degree

ABSTRACT When alleles are combined into few detectable classes, linkage correlations are underestimated most of the time. The probability that the linkage correlation will be underestimated is a function of the actual degree of correlation and the evenness of the allelic distribution, but is mainly determined by the distribution of alleles into distinguishable classes. With only two alleles per class this probability will usually be higher than 0.7. Also, the consistency in the sign of the linkage disequilibrium over many populations may escape detection. An increase of sample size by one order of magnitude or more may be required to compensate for the loss in detection power. It follows that the available electrophoretic studies of linkage correlations, although negative in their majority, do not suggest that epistatic interactions and linkage disequilibria are rare in natural populations.

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