Evaluating accuracy of community detection using the relative normalized mutual information

The Normalized Mutual Information (NMI) has been widely used to evaluate the accuracy of community detection algorithms. However in this article we show that the NMI is seriously affected by systematic errors due to finite size of networks, and may give a wrong estimate of performance of algorithms in some cases. We give a simple theory to the finite-size effect of NMI and test our theory numerically. Then we propose a new metric for the accuracy of community detection, namely the relative Normalized Mutual Information (rNMI), which considers statistical significance of the NMI by comparing it with the expected NMI of random partitions. Our numerical experiments show that the rNMI overcomes the finite-size effect of the NMI.Comment: comments are welcom

Tensor Transpose and Its Properties

Tensor transpose is a higher order generalization of matrix transpose. In this paper, we use permutations and symmetry group to define? the tensor transpose. Then we discuss the classification and composition of tensor transposes. Properties of tensor transpose are studied in relation to tensor multiplication, tensor eigenvalues, tensor decompositions and tensor rank

Lysine acetyltransferase 5 in EGFR mutated non-small cell lung cancer

Histone modifications are crucial in activities such as transcriptional activation, gene silencing, and epigenetic cellular memory. In particular, lysine acetylation via lysine (K) acetyltransferases (KATs) has been implicated in cancer development. Interestingly, KAT5, also known as Tip60 (tat-interactive protein-60kDa), has been reported to possess both tumor promoting and tumor suppressing properties depending on the context of malignancy. Herein we report that KAT5 contributes to tumorigenesis in epidermal growth factor receptor (EGFR) mutated lung cancer, and Kat5-knockout mice models demonstrate significantly reduced lung tumor burden. To probe the aberrant modification of KAT5, we demonstrated that KAT5 binds to and is phosphorylated by oncogenic EGFR in co-immunoprecipitation experiments. Next, to investigate whether KAT5 is involved in cell proliferation and survival, H1975 cells harboring L858R-T790M double-activating mutations were transfected with doxycycline inducible short helical RNA (shRNA) targeting KAT5 (shKAT5). Following treatment, shKAT5 cells were observed to have suppressed proliferation rates. Pharmacological inhibition using TH1834, a known KAT5 inhibitor, also suppressed proliferation rates in shKAT5 cells; in contrast BEAS2B cells, an immortalized normal human bronchial cell line, surprisingly exhibited increased viability compared to transformed human lung H1975 cells. This finding supports KAT5’s context-dependent role in in normal and abnormal cell homeostasis. To further investigate KAT5 in lung tumorigenesis in vivo, we generated EGFR-mutant conditional Kat5 knockout mice using a tetracycline-induced Cre/loxP system. Following doxycycline treatment for 10 weeks, isolated mice lungs for EGFRTL/CCSP-rtTA/Cre/Kat5F/F possessed significantly lower tumor volume compared to EGFRTL/CCSP-rtTA/Cre/Kat5wt/F and EGFRTL/CCSP-rtTA/Cre/Kat5wt/wt mice lungs. Hemotoxylin and eosin staining showed no evident hyperproliferation in lungs isolated from EGFRTL/CCSP-rtTA/Cre/Kat5F/F mice whereas lungs isolated from EGFRTL/CCSP-rtTA/Cre/Kat5wt/wt and EGFRTL/CCSP-rtTA/Cre/Kat5wt/F did, signifying that KAT5 has a potential regulatory role in cellular proliferation. RNA-Seq analysis of shKAT5 H1975 cells identified downstream targets involved in tumorigenic pathways. Subsequent quantitative polymerase chain reaction (PCR) of shKAT5 cells served to validate the reported targets. Taken together, these data offer insight into a KAT5 mediated oncogenic pathway that can provide novel therapeutic approaches in treating lung cancer

Propagation of Delayed Lattice Differential Equations without Local Quasimonotonicity

This paper is concerned with the traveling wave solutions and asymptotic spreading of delayed lattice differential equations without quasimonotonicity. The spreading speed is obtained by constructing auxiliary equations and using the theory of lattice differential equations without time delay. The minimal wave speed of invasion traveling wave solutions is established by presenting the existence and nonexistence of traveling wave solutions

Information Flow Model for Commercial Security

Information flow in Discretionary Access Control (DAC) is a well-known difficult problem. This paper formalizes the fundamental concepts and establishes a theory of information flow security. A DAC system is information flow secure (IFS), if any data never flows into the hands of owner’s enemies (explicitly denial access list.