4 research outputs found
A solution to the problem of clustered objects compact partitioning
The urgency of the study consists in the fact that an object arrangement topology of a distributed system is often nonuniform. Objects can be placed at different distances from each other, thus forming clusters. That is why solving the problem of compact partitioning into sets containing thousands of objects requires the most effective way to a better use of natural structuring of objects that form clusters. The aim of the study is the development of methods of compact partitioning of sets of objects presented as clusters. The research methods are based on applied theories of sets, theory of compact sets and compact partitions, and linear programming methods with Boolean variables. As a result, the paper offers the method necessary to analyze composition and content of clusters. It also evaluates cluster compactness, which results in the decision to include clusters into the sets of partitions. It addresses the problem of optimizing the rearrangement of objects between compact sets that form clusters, which is based on the criteria of maximizing the total compactness of sets. The problem is formulated in the class of objectives of linear programming methods with Boolean variables. It introduces the example of object rearrangement
A Large-Scale, Consortium-Based Genomewide Association Study of Asthma
BACKGROUND
Susceptibility to asthma is influenced by genes and environment;
implicated genes may indicate pathways for therapeutic intervention.
Genetic risk factors may be useful in identifying subtypes of asthma and
determining whether intermediate phenotypes, such as elevation of the
total serum IgE level, are causally linked to disease.
METHODS
We carried out a genomewide association study by genotyping 10,365
persons with physician-diagnosed asthma and 16,110 unaffected persons,
all of whom were matched for ancestry. We used random-effects pooled
analysis to test for association in the overall study population and in
subgroups of subjects with childhood-onset asthma (defined as asthma
developing before 16 years of age), later-onset asthma, severe asthma,
and occupational asthma.
RESULTS
We observed associations of genomewide significance between asthma and
the following single-nucleotide polymorphisms: rs3771166 on chromosome
2, implicating IL1RL1/IL18R1 (P = 3x10(-9)); rs9273349 on chromosome 6,
implicating HLA-DQ (P = 7x10(-14)); rs1342326 on chromosome 9, flanking
IL33 (P = 9x10(-10)); rs744910 on chromosome 15 in SMAD3 (P = 4x10(-9));
and rs2284033 on chromosome 22 in IL2RB (P = 1.1x10(-8)). Association
with the ORMDL3/GSDMB locus on chromosome 17q21 was specific to
childhood-onset disease (rs2305480, P = 6x10(-23)). Only HLA-DR showed a
significant genomewide association with the total serum IgE
concentration, and loci strongly associated with IgE levels were not
associated with asthma.
CONCLUSIONS
Asthma is genetically heterogeneous. A few common alleles are associated
with disease risk at all ages. Implicated genes suggest a role for
communication of epithelial damage to the adaptive immune system and
activation of airway inflammation. Variants at the ORMDL3/GSDMB locus
are associated only with childhood-onset disease. Elevation of total
serum IgE levels has a minor role in the development of asthma