829 research outputs found
Prospects for Measuring Vtb via s-channel Single Top at ATLAS
The production of single top quarks via the electroweak interaction promises to provide new opportunities to both test the Standard Model and search for new physics. In particular, electroweak top production provides the only means to directly measure the CKM matrix element Vtb at ATLAS. The s-channel has the lowest rate, but is the best theoretically understood mechanism of electroweak top production. An evaluation of the potential for background suppression and Vtb measurement in this channel is presented. It is found that significant background suppression can be achieved and Vtb can be measured in the s-channel to a statistical precision of 2.8% after 30 inverse femtobarns of integrated luminosity at the LHC
Class II Phosphoinositide 3-Kinases Contribute to Endothelial Cells Morphogenesis
PMCID: PMC3539993This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited
An efficient hardware architecture for a neural network activation function generator
This paper proposes an efficient hardware architecture for a function generator suitable for an artificial neural network (ANN). A spline-based approximation function is designed that provides a good trade-off between accuracy and silicon area, whilst also being inherently scalable and adaptable for numerous activation functions. This has been achieved by using a minimax polynomial and through optimal placement of the approximating polynomials based on the results of a genetic algorithm. The approximation error of the proposed method compares favourably to all related research in this field. Efficient hardware multiplication circuitry is used in the implementation, which reduces the area overhead and increases the throughput
Class II phosphoinositide 3-kinase C2 beta regulates a novel signaling pathway involved in breast cancer progression
It is now well established that the enzymes phosphoinositide 3-kinases (PI3Ks) have a key role in the development and progression of many cancer types and indeed PI3Ks inhibitors are currently being tested in clinical trials. Although eight distinct PI3K isoforms exist, grouped into three classes, most of the evidence currently available are focused on one specific isoform with very little known about the potential role of the other members of this family in cancer. Here we demonstrate that the class II enzyme PI3K-C2β is overexpressed in several human breast cancer cell lines and in human breast cancer specimens. Our data indicate that PI3K-C2β regulates breast cancer cell growth in vitro and in vivo and that PI3K-C2β expression in breast tissues is correlated with the proliferative status of the tumor. Specifically we show that downregulation of PI3K-C2β in breast cancer cell lines reduces colony formation, induces cell cycle arrest and inhibits tumor growth, in particular in an estrogen-dependent in vivo xenograft. Investigation of the mechanism of the PI3K-C2β-dependent regulation of cell cycle progression and cell growth revealed that PI3K-C2β regulates cyclin B1 protein levels through modulation of microRNA miR-449a levels. Our data further demonstrate that downregulation of PI3K-C2β inhibits breast cancer cell invasion in vitro and breast cancer metastasis in vivo. Consistent with this, PI3K-C2β is highly expressed in lymph-nodes metastases compared to matching primary tumors. These data demonstrate that PI3K-C2β plays a pivotal role in breast cancer progression and in metastasis development. Our data indicate that PI3K-C2β may represent a key molecular switch that regulates a rate-limiting step in breast tumor progression and therefore it may be targeted to limit breast cancer spread
The Minimal Supersymmetric Standard Model: Group Summary Report
CONTENTS: 1. Synopsis, 2. The MSSM Spectrum, 3. The Physical Parameters, 4.
Higgs Boson Production and Decays, 5. SUSY Particle Production and Decays, 6.
Experimental Bounds on SUSY Particle Masses, 7. References.Comment: 121 pages, latex + epsfig, graphicx, axodraw, Report of the MSSM
working group for the Workshop "GDR-Supersym\'etrie",France. Rep. PM/98-4
Science to Solutions Dialogue 3 - Everyone eating well within environmental limits
EAT and the World Business Council for Sustainable Development (WBCSD) convened through FReSH a Science to Solutions Dialogue (SSD) on Everyone Eating Well within Environmental Limits. This third dialogue took place from 4-7 December 2018 in Texcoco, Mexico, and brought together business, science and civil society to explore how to feed almost 10 billion people with sustainable and healthy diets. The summary of the discussion sets out three mutually supportive narratives to focus business action and the key solutions
In-Vivo Hyperspectral Human Brain Image Database for Brain Cancer Detection
The use of hyperspectral imaging for medical applications is becoming more
common in recent years. One of the main obstacles that researchers find when
developing hyperspectral algorithms for medical applications is the lack of
specific, publicly available, and hyperspectral medical data. The work
described in this paper was developed within the framework of the European
project HELICoiD (HypErspectraL Imaging Cancer Detection), which had as a main
goal the application of hyperspectral imaging to the delineation of brain
tumors in real-time during neurosurgical operations. In this paper, the
methodology followed to generate the first hyperspectral database of in-vivo
human brain tissues is presented. Data was acquired employing a customized
hyperspectral acquisition system capable of capturing information in the Visual
and Near InfraRed (VNIR) range from 400 to 1000 nm. Repeatability was assessed
for the cases where two images of the same scene were captured consecutively.
The analysis reveals that the system works more efficiently in the spectral
range between 450 and 900 nm. A total of 36 hyperspectral images from 22
different patients were obtained. From these data, more than 300 000 spectral
signatures were labeled employing a semi-automatic methodology based on the
spectral angle mapper algorithm. Four different classes were defined: normal
tissue, tumor tissue, blood vessel, and background elements. All the
hyperspectral data has been made available in a public repository.Comment: 19 pages, 12 figure
Evaluation of Hungarian Wines for Resveratrol by Overpressured Layer Chromatography
A method, including solid phase extraction sample preparation, overpressured layer chromatographic separation and subsequent densitometric evaluation, was developed for measurement of total resveratrol (cis- and trans-isomers) content of wine. The amount of resveratrol was determined in wine samples from different winemaking regions of Hungary. The total resveratrol was high in Hungarian red wines (3.6–11 mg/L), and much lower in white ones (0.04–1.5 mg/L)
Study of physiological maturity of melon seeds by enzymatic changes.
Thus, this study aimed to determine physiological and enzymatic changes during the maturation process of melon seeds of the cultivar BRS Anton, obtained from fruits at different maturation stages and subjected to post-harvest storage, by the action of total proteins and the enzymes catalase, peroxidase, and superoxide dismutase. Melon fruits were grown in a greenhouse at Embrapa Vegetables and harvested at five different times: 30, 45, 60, 75, and 90 days after anthesis (DAA)
- …