Primitive non-powerful symmetric loop-free signed digraphs with given base and minimum number of arcs

AbstractIn [B.M. Kim, B.C. Song, W. Hwang, Primitive graphs with given exponents and minimum number of edges, Linear Algebra Appl. 420 (2007) 648–662], the minimum number of edges of a simple graph on n vertices with exponent k was determined. In this paper, we completely determine the minimum number, H(n,k), of arcs of primitive non-powerful symmetric loop-free signed digraphs on n vertices with base k, characterize the underlying digraphs which have H(n,k) arcs when k is 2, nearly characterize the case when k is 3 and propose an open problem

Impact of Information Technology Capability on Financial Performance of Chinese Listed Companies during the Period of Economic Downturn

The information technology (IT) resource-based view suggests that IT capability is one of the determinants of a firm’s competitive advantage and financial performance. However, we know relatively little about the relationship between IT capability and financial performance during the period of economic downturn. Even fewer research related to this is done in China as the largest emerging We used the matched sample comparison group method to collect data from 248 listed companies before and after the 2008 financial crisis during 2007-2009, and to investigate the impacts of IT capability on financial performance during economic downturn. The findings show that even during the period of financial crisis, companies with superior IT capability have better average profit ratios than a control sample of companies, but differences in the cost ratio of suggest no statistical significance between two samples

Inferring Transcriptional Interactions by the Optimal Integration of ChIP-chip and Knock-out Data

How to combine heterogeneous data sources for reliable prediction of transcriptional regulation is a challenge. Here we present an easy but powerful method to integrate Chromatin immunoprecipitation (ChIP)-chip and knock-out data. Since these two types of data provide complementary (physical and functional) information about transcription, the method combining them is expected to achieve high detection rates and very low false positive rates. We try to seek the optimal integration of these two data using hyper-geometric distribution. We evaluate our method on yeast data and compare our predictions with YEASTRACT, high-quality ChIP-chip data, and literature. The results show that even using low-quality ChIP-chip data, our method uncovers more relations than those inferred before from high-quality data. Furthermore our method achieves a low false positive rate. We find experimental and computational evidence in literature for most transcription factor (TF)-gene relations uncovered by our method

OCT1 regulates the migration of colorectal cancer cells by acting on LDHA

Colorectal cancer is one of the most common cancers with high morbidity and mortality. Effective treatments to improve the prognosis are still lacking. The results of online analysis tools showed that OCT1 and LDHA were highly expressed in colorectal cancer, and the high expression of OCT1 was associated with poor prognosis. Immunofluorescence demonstrated that OCT1 and LDHA co-localized in colorectal cancer cells. In colorectal cancer cells, OCT1 and LDHA were upregulated by OCT1 overexpression, but downregulated by OCT1 knockdown. OCT1 overexpression promoted cell migration. OCT1 or LDHA knockdown inhibited the migration, and the downregulation of LDHA restored the promoting effect of OCT1 overexpression. OCT1 upregulation increased the levels of HK2, GLUT1 and LDHA proteins in colorectal cancer cells. Consequently, OCT1 promoted the migration of colorectal cancer cells by upregulating LDHA