Inverse Projection Representation and Category Contribution Rate for Robust Tumor Recognition

Sparse representation based classification (SRC) methods have achieved remarkable results. SRC, however, still suffer from requiring enough training samples, insufficient use of test samples and instability of representation. In this paper, a stable inverse projection representation based classification (IPRC) is presented to tackle these problems by effectively using test samples. An IPR is firstly proposed and its feasibility and stability are analyzed. A classification criterion named category contribution rate is constructed to match the IPR and complete classification. Moreover, a statistical measure is introduced to quantify the stability of representation-based classification methods. Based on the IPRC technique, a robust tumor recognition framework is presented by interpreting microarray gene expression data, where a two-stage hybrid gene selection method is introduced to select informative genes. Finally, the functional analysis of candidate's pathogenicity-related genes is given. Extensive experiments on six public tumor microarray gene expression datasets demonstrate the proposed technique is competitive with state-of-the-art methods.Comment: 14 pages, 19 figures, 10 table

2-(4-Chloro-1H-indol-3-yl)acetonitrile

The title compound, C10H7ClN2, contains two approximately planar mol­ecules, A and B (r.m.s. deviations = 0.039 and 0.064 Å, respectively) in the asymmetric unit. In the crystal, N—H⋯N hydrogen bonds link the mol­ecules into C(7) chains of alternating A and B mol­ecules propagating along the a-axis direction. The crystal used for the data collection was found to be a racemic twin

Poly[bis­[μ-1,4-bis­(imidazol-1-ylmeth­yl)benzene]­dichloridomanganese(II)]

In the crystal structure of the title compound, [MnCl2(C14H14N4)2]n, the MnII atom, lying on an inversion center, is coordinated by four N atoms from four 1,4-bis­(imidazol-1-ylmeth­yl)benzene (bimb) ligands and two Cl− anions in a distorted octa­hedral geometry. The bimb ligands bridge the MnII atoms, forming a two-dimensional polymeric complex, which is composed of a 52-membered [Mn4(bimb)4] ring with distances of 7.7812 (2) and 27.4731 (9) Å between opposite metal atoms. Weak C—H⋯π inter­actions are present in the crystal structure

4-Cyano-1-(4-nitro­benz­yl)pyridinium bis­(2-thioxo-1,3-dithiole-4,5-dithiol­ato-κ2 S 4,S 5)nickelate(III)

In the title salt, (C13H10N3O2)[Ni(C3S5)2], the NiIII cation is S,S′-chelated by two 2-thioxo-1,3-dithiole-4,5-dithiol­ate anions in a distorted square-planar geometry. The complex anion is approximately planar with a maximum deviation of 0.097 (1) Å. In the 1-(4-nitro­benz­yl)-4-cyano­pyridinium cation, the pyridine ring is twisted at a dihedral angle of 73.84 (16)° with respect to the benzene ring. π-π stacking is observed between nearly parallel [dihedral angle = 4.71 (7)°] dithiole and benzene rings, the centroid–centroid distance being 3.791 (2) Å