The Experts below are selected from a list of 14946 Experts worldwide ranked by ideXlab platform
Zohar Yakhini - One of the best experts on this subject based on the ideXlab platform.
-
Clinically driven semi-supervised Class discovery in gene expression data.
Bioinformatics (Oxford England), 2008Co-Authors: Israel Steinfeld, Roy Navon, Diego Ardigò, Ivana Zavaroni, Zohar YakhiniAbstract:Unsupervised Class discovery in gene expression data relies on the statistical signals in the data to exclusively drive the results. It is often the case, however, that one is interested in constraining the search space to respect certain biological prior knowledge while still allowing a flexible search within these boundaries. We develop an approach to semi-supervised Class discovery. One component of our approach uses clinical sample information to constrain the search space and guide the Class discovery process to yield biologically relevant partitions. A second component consists of using known biological annotation of genes to drive the search, seeking partitions that manifest strong differential expression in specific sets of genes. We develop efficient algorithmics for these tasks, implementing both approaches and combinations thereof. We show that our method is robust enough to detect known clinical parameters in accordance with expected clinical values. We also use our method to elucidate cardiovascular disease (CVD) putative risk factors. MonoClaD (Monotone Class Discovery). See http:// bioinfo.cs.technion.ac.il/people/zohar/MonoClad/. Supplementary data is available at http://bioinfo.cs.technion.ac.il/people/zohar/MonoClad/software. html
-
ECCB - Clinically driven semi-supervised Class discovery in gene expression data
2008Co-Authors: Israel Steinfeld, Roy Navon, Diego Ardigò, Ivana Zavaroni, Zohar YakhiniAbstract:Motivation: Unsupervised Class discovery in gene expression data relies on the statistical signals in the data to exclusively drive the results. It is often the case, however, that one is interested in constraining the search space to respect certain biological prior knowledge while still allowing a flexible search within these boundaries. Results: We develop an approach to semi-supervised Class discovery. One component of our approach uses clinical sample information to constrain the search space and guide the Class discovery process to yield biologically relevant partitions. A second component consists of using known biological annotation of genes to drive the search, seeking partitions that manifest strong differential expression in specific sets of genes. We develop efficient algorithmics for these tasks, implementing both approaches and combinations thereof. We show that our method is robust enough to detect known clinical parameters in accordance with expected clinical values. We also use our method to elucidate cardiovascular disease (CVD) putative risk factors. Availability: MonoClaD (Monotone Class Discovery). See http://bioinfo.cs.technion.ac.il/people/zohar/MonoClad/ Supplementary information: Supplementary data is available at http://bioinfo.cs.technion.ac.il/people/zohar/MonoClad/software.html Contact: zohar_yakhini@agilent.com
Alexandre Pinlou - One of the best experts on this subject based on the ideXlab platform.
-
A Complexity Dichotomy for the Coloring of Sparse Graphs
Journal of Graph Theory, 2012Co-Authors: Louis Esperet, Micka ¨ El Montassier, Pascal Ochem, Alexandre PinlouAbstract:Galluccio, Goddyn, and Hell proved in 2001 that in any minor-closed Class of graphs, graphs with large enough girth have a homomorphism to any given odd cycle. In this paper, we study the computational aspects of this problem. Let be a Monotone Class of graphs containing all planar graphs, and closed under clique-sum of order at most two. Examples of such Class include minor-closed Classes containing all planar graphs, and such that all minimal obstructions are 3-connected. We prove that for any k and g, either every graph of girth at least g in has a homomorphism to , or deciding whether a graph of girth g in has a homomorphism to is NP-complete. We also show that the same dichotomy occurs when considering 3-Colorability or acyclic 3-Colorability of graphs under various notions of density that are related to a question of Havel (On a conjecture of Grunbaum, J Combin Theory Ser B 7 (1969), 184–186) and a conjecture of Steinberg (The state of the three color problem, Quo Vadis, Graph theory?, Ann Discrete Math 55 (1993), 211–248) about the 3-Colorability of sparse planar graphs.
Israel Steinfeld - One of the best experts on this subject based on the ideXlab platform.
-
Clinically driven semi-supervised Class discovery in gene expression data.
Bioinformatics (Oxford England), 2008Co-Authors: Israel Steinfeld, Roy Navon, Diego Ardigò, Ivana Zavaroni, Zohar YakhiniAbstract:Unsupervised Class discovery in gene expression data relies on the statistical signals in the data to exclusively drive the results. It is often the case, however, that one is interested in constraining the search space to respect certain biological prior knowledge while still allowing a flexible search within these boundaries. We develop an approach to semi-supervised Class discovery. One component of our approach uses clinical sample information to constrain the search space and guide the Class discovery process to yield biologically relevant partitions. A second component consists of using known biological annotation of genes to drive the search, seeking partitions that manifest strong differential expression in specific sets of genes. We develop efficient algorithmics for these tasks, implementing both approaches and combinations thereof. We show that our method is robust enough to detect known clinical parameters in accordance with expected clinical values. We also use our method to elucidate cardiovascular disease (CVD) putative risk factors. MonoClaD (Monotone Class Discovery). See http:// bioinfo.cs.technion.ac.il/people/zohar/MonoClad/. Supplementary data is available at http://bioinfo.cs.technion.ac.il/people/zohar/MonoClad/software. html
-
ECCB - Clinically driven semi-supervised Class discovery in gene expression data
2008Co-Authors: Israel Steinfeld, Roy Navon, Diego Ardigò, Ivana Zavaroni, Zohar YakhiniAbstract:Motivation: Unsupervised Class discovery in gene expression data relies on the statistical signals in the data to exclusively drive the results. It is often the case, however, that one is interested in constraining the search space to respect certain biological prior knowledge while still allowing a flexible search within these boundaries. Results: We develop an approach to semi-supervised Class discovery. One component of our approach uses clinical sample information to constrain the search space and guide the Class discovery process to yield biologically relevant partitions. A second component consists of using known biological annotation of genes to drive the search, seeking partitions that manifest strong differential expression in specific sets of genes. We develop efficient algorithmics for these tasks, implementing both approaches and combinations thereof. We show that our method is robust enough to detect known clinical parameters in accordance with expected clinical values. We also use our method to elucidate cardiovascular disease (CVD) putative risk factors. Availability: MonoClaD (Monotone Class Discovery). See http://bioinfo.cs.technion.ac.il/people/zohar/MonoClad/ Supplementary information: Supplementary data is available at http://bioinfo.cs.technion.ac.il/people/zohar/MonoClad/software.html Contact: zohar_yakhini@agilent.com
Pan Zhi - One of the best experts on this subject based on the ideXlab platform.
-
Fuzzy algebra in triangular norm system
Fuzzy Sets and Systems, 1998Co-Authors: Song Xiao-qiu, Pan ZhiAbstract:Abstract Triangular norm is a powerful tool in the theory research and application development of fuzzy sets. In this paper, using the triangular norm, we introduce some concepts such as fuzzy algebra, fuzzy σ algebra, fuzzy Monotone Class, fuzzy π Class and fuzzy λ Class, and discuss the relations among them, obtaining a series of conclusions, main ones of which are fuzzy Monotone Class theorems (cf. Theorems 1–3).
Louis Esperet - One of the best experts on this subject based on the ideXlab platform.
-
A Complexity Dichotomy for the Coloring of Sparse Graphs
Journal of Graph Theory, 2012Co-Authors: Louis Esperet, Micka ¨ El Montassier, Pascal Ochem, Alexandre PinlouAbstract:Galluccio, Goddyn, and Hell proved in 2001 that in any minor-closed Class of graphs, graphs with large enough girth have a homomorphism to any given odd cycle. In this paper, we study the computational aspects of this problem. Let be a Monotone Class of graphs containing all planar graphs, and closed under clique-sum of order at most two. Examples of such Class include minor-closed Classes containing all planar graphs, and such that all minimal obstructions are 3-connected. We prove that for any k and g, either every graph of girth at least g in has a homomorphism to , or deciding whether a graph of girth g in has a homomorphism to is NP-complete. We also show that the same dichotomy occurs when considering 3-Colorability or acyclic 3-Colorability of graphs under various notions of density that are related to a question of Havel (On a conjecture of Grunbaum, J Combin Theory Ser B 7 (1969), 184–186) and a conjecture of Steinberg (The state of the three color problem, Quo Vadis, Graph theory?, Ann Discrete Math 55 (1993), 211–248) about the 3-Colorability of sparse planar graphs.