Вплив пропелерної модуляції на ефективність просторової режекції завад адаптивними антенами бортових систем зв'язку

Розглянуто проблему впливу пропелерної модуляції на ефективність просторової режекції завад адаптивними антенами бортових систем зв’язку

Seeing the forest for the trees: using the Gene Ontology to restructure hierarchical clustering

Motivation: There is a growing interest in improving the cluster analysis of expression data by incorporating into it prior knowledge, such as the Gene Ontology (GO) annotations of genes, in order to improve the biological relevance of the clusters that are subjected to subsequent scrutiny. The structure of the GO is another source of background knowledge that can be exploited through the use of semantic similarity

A factor model to analyze heterogeneity in gene expression

<p>Abstract</p> <p>Background</p> <p>Microarray technology allows the simultaneous analysis of thousands of genes within a single experiment. Significance analyses of transcriptomic data ignore the gene dependence structure. This leads to correlation among test statistics which affects a strong control of the false discovery proportion. A recent method called FAMT allows capturing the gene dependence into factors in order to improve high-dimensional multiple testing procedures. In the subsequent analyses aiming at a functional characterization of the differentially expressed genes, our study shows how these factors can be used both to identify the components of expression heterogeneity and to give more insight into the underlying biological processes.</p> <p>Results</p> <p>The use of factors to characterize simple patterns of heterogeneity is first demonstrated on illustrative gene expression data sets. An expression data set primarily generated to map QTL for fatness in chickens is then analyzed. Contrarily to the analysis based on the raw data, a relevant functional information about a QTL region is revealed by factor-adjustment of the gene expressions. Additionally, the interpretation of the independent factors regarding known information about both experimental design and genes shows that some factors may have different and complex origins.</p> <p>Conclusions</p> <p>As biological information and technological biases are identified in what was before simply considered as statistical noise, analyzing heterogeneity in gene expression yields a new point of view on transcriptomic data.</p

Complex trait subtypes identification using transcriptome profiling reveals an interaction between two QTL affecting adiposity in chicken

<p>Abstract</p> <p>Background</p> <p>Integrative genomics approaches that combine genotyping and transcriptome profiling in segregating populations have been developed to dissect complex traits. The most common approach is to identify genes whose eQTL colocalize with QTL of interest, providing new functional hypothesis about the causative mutation. Another approach includes defining subtypes for a complex trait using transcriptome profiles and then performing QTL mapping using some of these subtypes. This approach can refine some QTL and reveal new ones.</p> <p>In this paper we introduce Factor Analysis for Multiple Testing (FAMT) to define subtypes more accurately and reveal interaction between QTL affecting the same trait. The data used concern hepatic transcriptome profiles for 45 half sib male chicken of a sire known to be heterozygous for a QTL affecting abdominal fatness (AF) on chromosome 5 distal region around 168 cM.</p> <p>Results</p> <p>Using this methodology which accounts for hidden dependence structure among phenotypes, we identified 688 genes that are significantly correlated to the AF trait and we distinguished 5 subtypes for AF trait, which are not observed with gene lists obtained by classical approaches. After exclusion of one of the two lean bird subtypes, linkage analysis revealed a previously undetected QTL on chromosome 5 around 100 cM. Interestingly, the animals of this subtype presented the same q paternal haplotype at the 168 cM QTL. This result strongly suggests that the two QTL are in interaction. In other words, the "q configuration" at the 168 cM QTL could hide the QTL existence in the proximal region at 100 cM. We further show that the proximal QTL interacts with the previous one detected on the chromosome 5 distal region.</p> <p>Conclusion</p> <p>Our results demonstrate that stratifying genetic population by molecular phenotypes followed by QTL analysis on various subtypes can lead to identification of novel and interacting QTL.</p

The utility and predictive value of combinations of low penetrance genes for screening and risk prediction of colorectal cancer

Despite the fact that colorectal cancer (CRC) is a highly treatable form of cancer if detected early, a very low proportion of the eligible population undergoes screening for this form of cancer. Integrating a genomic screening profile as a component of existing screening programs for CRC could potentially improve the effectiveness of population screening by allowing the assignment of individuals to different types and intensities of screening and also by potentially increasing the uptake of existing screening programs. We evaluated the utility and predictive value of genomic profiling as applied to CRC, and as a potential component of a population-based cancer screening program. We generated simulated data representing a typical North American population including a variety of genetic profiles, with a range of relative risks and prevalences for individual risk genes. We then used these data to estimate parameters characterizing the predictive value of a logistic regression model built on genetic markers for CRC. Meta-analyses of genetic associations with CRC were used in building science to inform the simulation work, and to select genetic variants to include in logistic regression model-building using data from the ARCTIC study in Ontario, which included 1,200 CRC cases and a similar number of cancer-free population-based controls. Our simulations demonstrate that for reasonable assumptions involving modest relative risks for individual genetic variants, that substantial predictive power can be achieved when risk variants are common (e.g., prevalence > 20%) and data for enough risk variants are available (e.g., ~140–160). Pilot work in population data shows modest, but statistically significant predictive utility for a small collection of risk variants, smaller in effect than age and gender alone in predicting an individual’s CRC risk. Further genotyping and many more samples will be required, and indeed the discovery of many more risk loci associated with CRC before the question of the potential utility of germline genomic profiling can be definitively answered

Application of bonds in financing of mining-geological projects in the world markets

W artykule przedstawiono zmiany w finansowaniu projektów górniczo-geologicznych, które nastąpiły na rynkach światowych w kontekście kryzysu finansowego. Zwrócono szczególną uwagę na dotychczasowe, rekordowe zadłużenie przedsiębiorstw branży górniczej i pokazano kierunki zmian oparte na dokapitalizowaniu poprzez emisję nowych serii akcji oraz emisje obligacji zamiennych na akcje i obligacji zwykłych. Zaprezentowano największych emitentów obligacji oraz parametry emitowanych obligacji w postaci wysokości oprocentowania i terminu wykupu. Załączone wnioski potwierdzają obniżenie poziomu dźwigni finansowej, a tym samym ryzyka finansowego i dopasowanie finansowania do przepływów generowanych z aktualnie realizowanych i potencjalnych projektów górniczo-geologicznych. Według Ernst&Young należy oczekiwać powrotu poziomu zadłużenia do wielkości historycznych, kiedy to wskaźnik zadłużenia kapitału własnego długiem odsetkowym w branży górniczej wynosił średnio pomiędzy 20-40%.In the paper, it was presented the changes in financing of mining-geological projects which occurred in the world markets in the light of financial crisis. Particularly, it was paid attention on the record debt of mining sector and shown the practical directions of changes through secondary equity issues, convertible bonds and common bonds. It was presented the largest issuers of bonds in 2009 and parameters of issues like coupons and terms to maturity. Disclosed conclusions confirm the decrease financial leverage and risk in mining enterprises. The financing was matched to cash flows from existing and future mining-geological projects. According to Ernst&Young, the level of debt in mining sector will come back to historical value when debt to equity ratio was average 20-40%

Decision to close a geological-mining project supported by Real Option Valuation method

W artykule przedstawiono możliwości wykorzystania rachunku opcji rzeczywistych do wspomagania procesów decyzyjnych na etapie zamknięcia projektu geologiczno-górniczego. Przedstawione problemy badawcze zidentyfikowano w trzech obszarach. W pierwszym z nich opisano projekt geologiczno-górniczy i etapy składające się na cykl jego życia. W drugim obszarze scharakteryzowano metodologię rachunku opcji rzeczywistych i jego historyczne zastosowanie w problemach decyzyjnych branży górniczej. Trzeci obszar stanowiący realizację celu głównego artykułu wskazuje na dwa modele opcji rzeczywistych mogących wspomagać decyzję zamknięcia lub kontynuacji funkcjonowania projektu geologiczno-górniczego.This paper presents the opportunities of real option applications to support the decision-making process in the phase of geological-mining project closure. Research problems mentioned in this paper were identified in three areas. The first one described idea of geological-mining project and the phases of the whole life cycle. In the second area methodology of real option valuation and application in the decision-making process in mining industry were characterized. The third area is an essential part of the paper and presents two models of real option valuations in the decision-making process to close or continue the implementation of geological-mining projects

Wartość dodana dla interesariuszy przedsiębiorstw górniczych oparta na przepływach pieniężnych

The purpose of this article is to present certain trends in the distribution of value created by businesses for groups of stakeholders as part of a conception of sustainable growth. The articles defines value, who this value should benefit, and in what way it should be distributed. A method for measuring distributed value based on cash flow is demonstrated. The current value of this cash flow within a definite timeframe may serve as a potential indicator for the continuation or liquidation of operations in terms of the maintenance or loss of benefit for stakeholders.Celem artykułu jest przedstawienie aktualnych trendów w koncepcji dystrybuowania wartości dla interesariuszy jako obszaru zarządzania opartego na zrównoważonym rozwoju. Artykuł definiuje wartość jako korzyść i sposoby jej pomiaru. Jednocześnie zaprezentowano pomiar dystrybuowanej wartości dla interesariuszy na podstawie dynamicznego podejścia opartego na przepływach pieniężnych. Wartość dodana oparta na przepływach pieniężnych dla interesariuszy może stanowić potencjalny miernik do podejmowania decyzji dotyczących kontynuacji lub likwidacji działalności