Mutations and the value of information.

On the basis of the literary data the relative probabilities of the point mutations are evaluated in the proteins and in RNA's. The relative probabilities of the nonsense mutations are estimated. The probability of the nonsense mutation of the codon UGG (Trp) is especially high. The notion of the value of information is introduced as the measure of the irreplaceability of an element of a message. Using the data on replaceabilities of the amino-acidic residues the tentative values of information of the codons and of the amino-acidic residues are determined. The value, i.e. the irreplaceability of the information increases in the course of biological development. The increase of the summary value of the protein chain of cytochrome c in phylogenesis is shown. The increase of the value of information correlates with the increase of the entropy of a protein chain.     

The fitness value of information

Communication and information are central concepts in evolutionary biology. In fact, it is hard to find an area of biology where these concepts are not used. However, quantifying the information transferred in biological interactions has been difficult. How much information is transferred when the first spring rainfall hits a dormant seed, or when a chick begs for food from its parent? One measure that is commonly used in such cases is fitness value: by how much, on average, an individual's fitness would increase if it behaved optimally with the new information, compared to its average fitness without the information. Another measure, often used to describe neural responses to sensory stimuli, is the mutual information – a measure of reduction in uncertainty, as introduced by Shannon in communication theory. However, mutual information has generally not been considered to be an appropriate measure for describing developmental or behavioral responses at the organismal level, because it is blind to function; it does not distinguish between relevant and irrelevant information. In this paper we show that there is in fact a surprisingly tight connection between these two measures in the important context of evolution in an uncertain environment. In this case, a useful measure of fitness benefit is the increase in the long‐term growth rate, or the fold increase in number of surviving lineages. We show that in many cases the fitness value of a developmental cue, when measured this way, is exactly equal to the reduction in uncertainty about the environment, as described by the mutual information.     

On estimating the heterozygosity and polymorphism information content value

The polymorphism information content (PIC) value is commonly used in genetics as a measure of polymorphism for a marker locus used in linkage analysis. In this communication we have derived the uniformly minimum variance unbiased estimator of PIC along with its exact variance. We have also calculated the exact variance of the maximum likelihood estimator of PIC which is asymptotically an unbiased estimator. In order to find this variance we have derived a recursive formula to calculate the moments of any polynomial in a set of variables that are multinomially distributed.     

Principal agent model based design and outsourcing of information value

IT outsourcing allows a business to reduce the cost of IT service delivery and improve the quality of IT service by taking advantage of the service provider’s economics of scale and technical expertise. However, the successful outsourcing of IT service is hampered by lack of guidance on how to design incentive contracts to encourage performance of the service provider, especially in the presence of information asymmetry and incentive divergence. In this article, we identify and characterize two asymmetric information factors: asymmetric effort information and asymmetric capability information. Depending on whether the service provider’s effort information and capability information is symmetric or not, we consider three information scenarios and characterize optimal incentive contracts for each scenario. We also introduce the concept of information value to quantify the adverse effects of the two asymmetric information factors. The results provide theoretical support for designing incentive contracts that mitigate the adverse effects of asymmetric information, and recommend effective guidance for activities so as to reduce the degree of information asymmetry.     

The value of information in reserve site selection

The reserve site selection problem is to select sites for the establishment of biological reserves with the goal to maximize the number of species contained in the reserves. When species distributions are known, this corresponds to the maximal coverage problem. In practice, knowledge of species distributions may be incomplete and only incidence probabilities are available. In this case, the goal is to maximize the expected number of species contained in the reserves. This is called the maximal expected coverage problem. This paper describes and illustrates a formal approach to assess the value of information, such as site surveys or species surveys, in this problem.     

The problem of information value in microvascular networks

A novel methodology of quantitative estimation of the information value in microvascular networks is proposed. The methodology has been developed on the basis of the results of wavelet analysis of skin blood flow oscillations measured by means of laser Doppler flowmetry (LDF) in 30 healthy subjects and 56 patients with hand diseases or consequences of hand injuries. The method is based on the calculation of the relative indices of information preservation, dominance of the preserved information, and information effectiveness. The deviation from the multistable information regimen is the largest in the case of resonance oscillations: the total information quantity is significantly decreased; however, the preservation of dominant information and its effectiveness are improved. The preservation of trophic myogenic information predominates upon reduction of sympathetic influences. An increase in the number of information channels increases only the information quantity, whereas the degree of its preservation varies. Sensory peptidergic nerve fibers are activated in response to local heating of the dorsal forearm skin to 34°C. This information is the most effective at the beginning of the heating, when the blood flow increases to a plateau. The blood flow oscillations represented in the wavelet spectrum of microcirculatory oscillations serve as operators based on effective information. These oscillations not only play the hemodynamic role, but also carry information in microvascular networks.     

The parameters of cardiac-muscle repolarization: The measurement and information value

We performed a comparative analysis of different classes of algorithms for computer-assisted cardiological diagnostics. The concepts of an “internal” and “external” image of myocardial ischemia were formulated. We also discussed the biophysical aspects for the basic indices of spatial heterogeneity of the repolarization process in the myocardium, as well as the problems of measurement of the corresponding parameters. The experimental part was performed on two groups of patients. Both experimental and control groups included two sets of 12-lead electrocardiograms of real patients: “Normal” and “Ischemia” (with lateral localization). The experimental group consisted of 202 and 143 electrocardiograms, while the control group consisted of 200 and 91 electrocardiograms, respectively. The electrocardiograms were verified according to the Minnesota Code criteria.     

Fisher information for a multivariate extreme value distribution

Explicit algebraic formulae for the Fisher information matrixof the multivariate extreme value distribution with generalisedextreme value margins and logistic dependence structure aregiven.     

Short review: Field recovery and potential information value of small elements of the skeleton

The recovery of small elements of the skeleton (e.g. hyoid, carpals, and hand and foot phalanges) is one of the established tasks of the archaeologist and physical anthropologist when working in the field, whether in an archaeological or forensic context. In the present work, we illustrate the field location of ossified laryngeal cartilages, hand sesamoids, and the medial clavicular epiphyses. The potential information offered by these elements is briefly summarized. The frequency of these elements observed in a cemetery dating from 1943 indicates the possibility that these elements could be found in other contexts at a higher frequency than expected.     

Reliability of the cut-off value in the routine serodiagnosis of pertussis performed by the commercial ELISA assays

In clinical practise, serodiagnosis of pertussis is mostly based on single-sample serology using a single cut-off. The reliability of the cut-off value has the crucial influence for the sensitivity and specificity of the used tests. In this context we compared the value of cut-off used in two commercial ELISA kits (NovaLisa Bordetella pertussis-NovaTec and ELISA Bordetella pertussis ELISA-Virotech) with cut-off settled by calculation the IgA and IgG results from the 60 healthy Polish children and 100 blood donors (arithmetic mean plus 2 or 3 standard deviations). Our study indicates that IgA cutoff used in NovaTec ELISA, in contrary to Virotech ELISA, correspond better to the level x+3SD calculated in children sera and x+2SD calculated in adult blood donors sera. The value of IgG cut-off used in Virotech ELISA was lower about 20% and 30% from the cut-off settled by us respectively on the level ofx+2SD and x+3SD in all tested sera. The most inadequate value had the IgG cut-offused in NovaTec ELISA, which was over three times lower than mean cut-off value settled by calculation results from the sera obtained from healthy children and blood donors. This low cut-off value established by the NovaTec was the reason that 23.3% of healthy children and 55.0% of blood donors have the IgG antibodies on the diagnostic significant level. Our data suggest that commercial ELISAs need further improvement and standardization.     

Tailoring information provision and consent processes to research contexts: the value of rapid assessments

Guidance requires that consent processes for research be appropriately tailored to their cultural context. This paper discusses the use of rapid assessments to identify cultural and ethical issues arising when explaining research in studies in The Gambia and Ethiopia. The assessments provided insights into appropriate ways of providing information to minimize the risk of stigmatizing vulnerable research populations; research participants' views about the most important information to provide about research and their understandings of research; and perceived constraints upon reaching voluntary decisions about participation. These insights demonstrate that rapid assessments are a relatively quick and inexpensive intervention that can provide valuable information to assist in the tailoring of information provision and consent processes to research context while maintaining and enhancing participants' fundamental protections.     

Comparative information value of humoral immunity characteristics in some bacterial and viral infections

Serological examination of 144 patients with different bacterial and viral infections was carried out. Antibodies to Brucella were detected in blood serum in 42 patients (85.7%) with the average titer of 1:996 and in saliva in 41 patients (83.7%) with the average titer of 1:567 by passive hemagglutination test with brucella erythrocyte diagnosticum. Out of 26 dysentery patients, antibodies in blood serum were detected in the diagnostic titer in 17 patients (65.4%) with the average titer of 1:282 and in saliva in 21 patients (80.8%) in the titer of 1:100 and higher. Anti-HAV and anti-HBc IgM were detected in specimens of saliva from patients with serologically confirmed viral hepatitis A and B in 100% of cases. The presence of HBsAg in saliva from hepatitis B patients was established in 95.4% of cases. In blood serum and in specimens of saliva anti-HCV IgM were detected in 100% and 85.7% of cases respectively. Out of 25 women with aggravated obstetric history, IgG antibodies to CMV were detected in blood serum in 23 women (88.5%) and in saliva in 22 women (84.6%). The results of these investigations revealed that the detection rate of antibodies in blood serum and saliva in cases of infections, both bacterial (brucellosis, shigellosis) and viral (hepatitis A, B, C and CMV infection), was not essentially different. The simplicity of obtaining material for analysis make it possible to recommend the use of saliva for diagnosing bacterial and viral infections, especially in mass epidemiological surveys.     

How to derive biological information from the value of the normalization constant in allometric equations

Allometric equations are widely used in many branches of biological science. The potential information content of the normalization constant b in allometric equations of the form Y = bX(a) has, however, remained largely neglected. To demonstrate the potential for utilizing this information, I generated a large number of artificial datasets that resembled those that are frequently encountered in biological studies, i.e., relatively small samples including measurement error or uncontrolled variation. The value of X was allowed to vary randomly within the limits describing different data ranges, and a was set to a fixed theoretical value. The constant b was set to a range of values describing the effect of a continuous environmental variable. In addition, a normally distributed random error was added to the values of both X and Y. Two different approaches were then used to model the data. The traditional approach estimated both a and b using a regression model, whereas an alternative approach set the exponent a at its theoretical value and only estimated the value of b. Both approaches produced virtually the same model fit with less than 0.3% difference in the coefficient of determination. Only the alternative approach was able to precisely reproduce the effect of the environmental variable, which was largely lost among noise variation when using the traditional approach. The results show how the value of b can be used as a source of valuable biological information if an appropriate regression model is selected.