Bar-Ilan University

About: Bar-Ilan University is a education organization based out in Ramat Gan, Israel. It is known for research contribution in the topics: Population & Poison control. The organization has 12835 authors who have published 34964 publications receiving 995648 citations. The organization is also known as: Bar Ilan University & BIU.

Constrained Gaussian mixture model framework for automatic segmentation of MR brain images

Abstract: An automated algorithm for tissue segmentation of noisy, low-contrast magnetic resonance (MR) images of the brain is presented. A mixture model composed of a large number of Gaussians is used to represent the brain image. Each tissue is represented by a large number of Gaussian components to capture the complex tissue spatial layout. The intensity of a tissue is considered a global feature and is incorporated into the model through tying of all the related Gaussian parameters. The expectation-maximization (EM) algorithm is utilized to learn the parameter-tied, constrained Gaussian mixture model. An elaborate initialization scheme is suggested to link the set of Gaussians per tissue type, such that each Gaussian in the set has similar intensity characteristics with minimal overlapping spatial supports. Segmentation of the brain image is achieved by the affiliation of each voxel to the component of the model that maximized the a posteriori probability. The presented algorithm is used to segment three-dimensional, T1-weighted, simulated and real MR images of the brain into three different tissues, under varying noise conditions. Results are compared with state-of-the-art algorithms in the literature. The algorithm does not use an atlas for initialization or parameter learning. Registration processes are therefore not required and the applicability of the framework can be extended to diseased brains and neonatal brains

Targeted gold nanoparticles enable molecular CT imaging of cancer: an in vivo study.

Abstract: In recent years, advances in molecular biology and cancer research have led to the identification of sensitive and specific biomarkers that associate with various types of cancer. However, in vivo cancer detection methods with computed tomography, based on tracing and detection of these molecular cancer markers, are unavailable today. This paper demonstrates in vivo the feasibility of cancer diagnosis based on molecular markers rather than on anatomical structures, using clinical computed tomography. Anti-epidermal growth factor receptor conjugated gold nanoparticles (30 nm) were intravenously injected into nude mice implanted with human squamous cell carcinoma head and neck cancer. The results clearly demonstrate that a small tumor, which is currently undetectable through anatomical computed tomography, is enhanced and becomes clearly visible by the molecularly-targeted gold nanoparticles. It is further shown that active tumor targeting is more efficient and specific than passive targeting. This noninvasive and nonionizing molecular cancer imaging tool can facilitate early cancer detection and can provide researchers with a new technique to investigate in vivo the expression and activity of cancer-related biomarkers and molecular processes.

Family language policy – the critical domain

Abstract: Introducing a pioneering series of studies of family language policy and management, this paper points out that classic language policy dealt almost entirely with the nation-state, although it did recognise the critical role of the family in determining natural intergenerational transmission of a variety. After arguing for the need to look at each of the levels, or, rather, domains making up a speech or political community, it shows how these studies deal with internal pressures (such as ideology or grandparents) and external domains (especially the school) which aim to influence the family domain. More studies of these domains, including the family, are needed to provide a clear understanding of language policy.

Synthesis of Nanosized α-Nickel Hydroxide by a Sonochemical Method

Abstract: Nanosized α-nickel hydroxide with an interlayer spacing of 7.2 A has been synthesized with the aid of ultrasound radiation. This method was found to be a simple and convenient method to produce α-nickel hydroxide. The synthesized hydroxide was found to possess good stability in KOH medium and the material might be interesting from the application point of view in secondary alkaline batteries. The α-nickel hydroxide has been characterized by powder X-ray diffraction, transmission electron microscopy, DSC, thermogravimetric analysis, FT-IR spectroscopy, and elemental analysis.