Developing Knowledge Models of Social Media: A Case Study on LinkedIn

User Generated Content (UGC) exchanged via large Social Network is considered a very important knowledge source about all aspects of the social engagements (e.g. interests, events, personal information, personal preferences, social experience, skills etc.). However this data is inherently unstructured or semi-structured. In this paper, we describe the results of a case study on LinkedIn Ireland public profiles. The study investigated how the available knowledge could be harvested from LinkedIn in a novel way by developing and applying a reusable knowledge model using linked open data vocabularies and semantic web. In addition, the paper discusses the crawling and data normalisation strategies that we developed, so that high quality metadata could be extracted from the LinkedIn public profiles. Apart from the search engine in LinkedIn.com itself, there are no well known publicly available endpoints that allow users to query knowledge concerning the interests of individuals on LinkedIn. In particular, we present a system that extracts and converts information from raw web pages of LinkedIn public profiles into a machine-readable, interoperable format using data mining and Semantic Web technologies. The outcomes of our research can be summarized as follows: (1) A reusable knowledge model which can represent LinkedIn public users and company profiles using linked data vocabularies and structured data, (2) a public SPARQL endpoint to access structured data about Irish industry and public profiles, (3) a scalable data crawling strategy and mashup based data normalisation approach. The proposed data mining and knowledge representation proposed in this paper are evaluated in four ways: (1) We evaluate metadata quality using automated techniques, such as data completeness and data linkage. (2) Data accuracy is evaluated via user studies. In particular, accuracy is evaluated by comparison of manually entered metadata fields and the metadata which was automatically extracted. (3) User perceived metadata quality is measured by asking users to rate the automatically extracted metadata in user studies. (4) Finally, the paper discusses how the extracted metadata suits for a user interface design. Overall, the evaluations show that the extracted metadata is of high quality and meets the requirements of a data visualisation user interface

The Escherichia coli RutR transcription factor binds at targets within genes as well as intergenic regions.

The Escherichia coli RutR protein is the master regulator of genes involved in pyrimidine catabolism. Here we have used chromatin immunoprecipitation in combination with DNA microarrays to measure the binding of RutR across the chromosome of exponentially growing E. coli cells. Twenty RutR-binding targets were identified and analysis of these targets generated a DNA consensus logo for RutR binding. Complementary in vitro binding assays showed high-affinity RutR binding to 16 of the 20 targets, with the four low-affinity RutR targets lacking predicted key binding determinants. Surprisingly, most of the DNA targets for RutR are located within coding segments of the genome and appear to have little or no effect on transcript levels in the conditions tested. This contrasts sharply with other E. coli transcription factors whose binding sites are primarily located in intergenic regions. We suggest that either RutR has yet undiscovered function or that evolution has been slow to eliminate non-functional DNA sites for RutR because they do not have an adverse effect on cell fitness

DIMP53-1:A novel small-molecule dual inhibitor of p53-MDM2/X interactions with multifunctional p53-dependent anticancer properties

The transcription factor p53 plays a crucial role in cancer development and dissemination, and thus, p53-targeted therapies are among the most encouraging anticancer strategies. In human cancers with wild-type (wt) p53, its inactivation by interaction with murine double minute (MDM)2 and MDMX is a common event. Simultaneous inhibition of the p53 interaction with both MDMs is crucial to restore the tumor suppressor activity of p53. Here, we describe the synthesis of the new tryptophanol-derived oxazoloisoindolinone DIMP53-1 and identify its activity as a dual inhibitor of the p53-MDM2/X interactions using a yeast-based assay. DIMP53-1 caused growth inhibition, mediated by p53 stabilization and upregulation of p53 transcriptional targets involved in cell cycle arrest and apoptosis, in wt p53-expressing tumor cells, including MDM2- or MDMX-overexpressing cells. Importantly, DIMP53-1 inhibits the p53-MDM2/X interactions by potentially binding to p53, in human colon adenocarcinoma HCT116 cells. DIMP53-1 also inhibited the migration and invasion of HCT116 cells, and the migration and tube formation of HMVEC-D endothelial cells. Notably, in human tumor xenograft mice models, DIMP53-1 showed a p53-dependent antitumor activity through induction of apoptosis and inhibition of proliferation and angiogenesis. Finally, no genotoxicity or undesirable toxic effects were observed with DIMP53-1. In conclusion, DIMP53-1 is a novel p53 activator, which potentially binds to p53 inhibiting its interaction with MDM2 and MDMX. Although target-directed, DIMP53-1 has a multifunctional activity, targeting major hallmarks of cancer through its antiproliferative, proapoptotic, antiangiogenic, anti-invasive, and antimigratory properties. DIMP53-1 is a promising anticancer drug candidate and an encouraging starting point to develop improved derivatives for clinical application

Optical and Infrared Light Curves of the Eclipsing X-ray Binary V395 Car = 2S 0921-630

We present results of optical and infrared photometric monitoring of the eclipsing low-mass X-ray binary V395 Car (2S 0921-630). Our observations reveal a clear, repeating orbital modulation with an amplitude of about one magnitude in B, and V and a little less in J. Combining our data with archival observations spanning about 20 years, we derive an updated ephemeris with orbital period 9.0026+/-0.0001d. We attribute the modulation to a combination of the changing aspect of the irradiated face of the companion star and eclipses of the accretion disk around the neutron star. Both appear to be necessary as a secondary eclipse of the companion star is clearly seen. We model the B, V, and J lightcurves using a simple model of an accretion disk and companion star and find a good fit is possible for binary inclinations of 82.2+/-1.0 degrees. We estimate the irradiating luminosity to be about 8x10^35 erg/s, in good agreement with X-ray constraints.Comment: 6 pages, accepted for publication in MNRA

An hypothesis on crustacean pigmentation metabolism:L-carnitine and nuclear hormone receptors as limiting factors

Astaxanthin (Axn) is the primary pigment molecule in crustaceans associated with quality, health and growth traits, leading to increased marketing value. Axn can be contained within the protein complex crustacyanin (CRCN) to produce an array of different shell colours, or esterified with fatty acids (FA) for storage but also contributing additional red colouration. l-Carnitine (LC) has a major role in FA oxidation and mitochondrial function optimization, which could influence the proportion of Axn complexed with FA or CRCN. Peroxisome proliferator activated receptors (PPARs) have important roles in FA and Axn uptake, and stored lipid oxidation affecting Axn homeostasis and storage in lipid bodies. Whether Axn could increase PPAR signalling and carnitine palmitoyl transferase activity, leading to induction of lipid metabolism, is not known in crustaceans. Several FA have been shown to preferentially form FA Axn-esters, including saturated fatty acids (SFA) such as C16:0 and C18:0, mono-unsaturated fatty acids (MUFA) such as C16:1 and C18:1, and poly-unsaturated fatty acids (PUFA) such as C20:4, C20:5, and C20:6. We hypothesize that manipulating the dietary ratios and inclusion of LC, Axn, and specific FA may be able to further improve pigment utilization, lipid metabolism, health, and growth in crustaceans.</p

AV-Courant algebroids and generalized CR structures

We construct a generalization of Courant algebroids which are classified by the third cohomology group $H^3(A,V)$, where $A$ is a Lie Algebroid, and $V$ is an $A$-module. We see that both Courant algebroids and $\mathcal{E}^1(M)$ structures are examples of them. Finally we introduce generalized CR structures on a manifold, which are a generalization of generalized complex structures, and show that every CR structure and contact structure is an example of a generalized CR structure.Comment: 18 page

Divergent functions for airway epithelial matrix metalloproteinase 7 and retinoic acid in experimental asthma.

The innate immune response of airway epithelial cells to airborne allergens initiates the development of T cell responses that are central to allergic inflammation. Although proteinase allergens induce the expression of interleukin 25, we show here that epithelial matrix metalloproteinase 7 (MMP7) was expressed during asthma and was required for the maximum activity of interleukin 25 in promoting the differentiation of T helper type 2 cells. Allergen-challenged Mmp7(-/-) mice had less airway hyper-reactivity and production of allergic inflammatory cytokines and higher expression of retinal dehydrogenase 1. Inhibition of retinal dehydrogenase 1 restored the asthma phenotype of Mmp7(-/-) mice and inhibited the responses of lung regulatory T cells, whereas exogenous administration of retinoic acid attenuated the asthma phenotype. Thus, MMP7 coordinates allergic lung inflammation by activating interleukin 25 while simultaneously inhibiting retinoid-dependent development of regulatory T cells

Long-term photometric behaviour of XZ Dra Binarity or magnetic cycle of a Blazhko type RRab star

The extended photometry available for XZ Dra, a Blazhko type RR Lyrae star, makes it possible to study its long-term behavior. It is shown that its pulsation period exhibit cyclic, but not strictly regular variations with approx. 7200 d period. The Blazhko period (approx. 76 d) seems to follow the observed period changes of the fundamental mode pulsation with dP_B/dP_0=7.7 x 10^4 gradient. Binary model cannot explain this order of period change of the Blazhko modulation, nevertheless it can be brought into agreement with the O-C data of the pulsation. The possibility of occurrence of magnetic cycle is raised.Comment: 13 pages, 11 figures (submitted to A&A