EBF1-deficient bone marrow stroma elicits persistent changes in HSC potential

Crosstalk between mesenchymal stromal cells (MSCs) and hematopoietic stem cells (HSCs) is essential for hematopoietic homeostasis and lineage output. Here, we investigate how transcriptional changes in bone marrow (BM) MSCs result in long-lasting effects on HSCs. Single-cell analysis of Cxcl12-abundant reticular (CAR) cells and PDGFRα+Sca1+ (PαS) cells revealed an extensive cellular heterogeneity but uniform expression of the transcription factor gene Ebf1. Conditional deletion of Ebf1 in these MSCs altered their cellular composition, chromatin structure and gene expression profiles, including the reduced expression of adhesion-related genes. Functionally, the stromal-specific Ebf1 inactivation results in impaired adhesion of HSCs, leading to reduced quiescence and diminished myeloid output. Most notably, HSCs residing in the Ebf1-deficient niche underwent changes in their cellular composition and chromatin structure that persist in serial transplantations. Thus, genetic alterations in the BM niche lead to long-term functional changes of HSCs

Coupled-barrier diffusion: the case of oxygen in silicon

Oxygen migration in silicon corresponds to an apparently simple jump between neighboring bridge sites. Yet, extensive theoretical calculations have so far produced conflicting results and have failed to provide a satisfactory account of the observed $2.5$ eV activation energy. We report a comprehensive set of first-principles calculations that demonstrate that the seemingly simple oxygen jump is actually a complex process involving coupled barriers and can be properly described quantitatively in terms of an energy hypersurface with a ``saddle ridge'' and an activation energy of $\sim 2.5$ eV. Earlier calculations correspond to different points or lines on this hypersurface.Comment: 4 Figures available upon request. Accepted for publication in Phys. Rev. Let

Seasonal landings of oil sardine, Sardinella longiceps at Rameswaram, Pamban and Mandapam areas

Unusual and unprecedented landings of oil sardine, Sardinella langiceps were noticed at Rameswaram and Pamban during January and February 1992. The estimated catch of oil sardine at Rameswaram for January- February 1992 was 4,561 t. The pair trawlers contributed 4,244 t and fish trawlers 317 t. The C/E varied from 1.5 to 8 t. At Pamban the pair trawling during the period realised 741 t

On the sunfish, Masturus lanceolatus landed near Ervadi, Gulf of Mannar

A sunfish, Masturus lanceolatus, commonly Sadaimuniyan aalasai, near Ervadi along the known as sharptail mola belonging to the family Gulf of Mannar coast on 21-05-2007. The Molidae was drifted ashore in specimen measured a total length of 840 m

Structure and apparent topography of TiO2 (110) surfaces

We present self-consistent ab-initio total-energy and electronic-structure calculations on stoichiometric and non-stoichiometric TiO2 (110) surfaces. Scanning tunneling microscopy (STM) topographs are simulated by calculating the local electronic density of states over an energy window appropriate for the experimental positive-bias conditions. We find that under these conditions the STM tends to image the undercoordinated Ti atoms, in spite of the physical protrusion of the O atoms, giving an apparent reversal of topographic contrast on the stoichiometric 1x1 or missing-row 2x1 surface. We also show that both the interpretation of STM images and the direct comparison of surface energies favor an added-row structure over the missing-row structure for the oxygen-deficient 2x1 surface.Comment: 6 pages, two-column style with 5 postscript figures embedded. Uses REVTEX and epsf macros. Also available at http://www.physics.rutgers.edu/~dhv/preprints/index.html#ng_tio

Electron interference and entanglement in coupled 1D systems with noise

We estimate the role of noise in the formation of entanglement and in the appearance of single- and two-electron interference in systems of coupled one-dimensional channels semiconductors. Two cases are considered: a single-particle interferometer and a two-particle interferometer exploiting Coulomb interaction. In both of them, environmental noise yields a randomization of the carrier phases. Our results assess how that the complementarity relation linking single-particle behavior to nonlocal quantities, such as entanglement and environment-induced decoherence, acts in electron interferometry. We show that, in a experimental implementation of the setups examined, one- and two-electron detection probability at the output drains can be used to evaluate the decoherence phenomena and the degree of entanglement.Comment: 12 pages, 6 figures. v2: added some references and corrected tex

Opinion Poll: Big Data Implementation of Unstructured Data Analytics of Social Network Reviews Using Sentiment Analysis SVM

Recent systems developed are dependent on user feedbacks or opinions. These feedbacks or opinions are generated in volumes everyday which are difficult to filter and analyse. We propose Sentiment based analysis is the major key in categorizing the user\u27s Feedback. In thispaper, we study the processing of all the reviews posted in an online shopping application and classify them using SVM. We use big data to analyze the vast amounts of data generated. User reviews are the input to the Big Data HDFS System. Data are stored in the Data Nodes. Index is maintained in the Name Node. Reviews are analyzed using Sentiment Analysis and Positive Negative Tweets are classified. Also products are recommended based on the previous purchases and group notification is sent to all the customers in a group