Sökresultat

Filtyp

Din sökning på "*" gav 533069 sökträffar

Measurement of MR signal and T2* in lung to characterize a tight skin mouse model of emphysema using single-point imaging

PURPOSE: To evaluate whether MRI signal and T2* measurements of lung tissue acquired at ultrashort detection times (tds) can detect emphysematous changes in lungs.MATERIALS AND METHODS: MR signal intensity of in vivo mouse lungs was measured at 4.7 T at tds of 0.2 and 0.4 msec using single-point imaging (SPI). T2* was calculated from the measurements obtained at the two tds. Two groups of 8- and 3

Multiplanar MR temperature-sensitive imaging of cerebral thermal treatment using interstitial ultrasound applicators in a canine model

PURPOSE: To study the feasibility of an interleaved gradient-echo, echo-planar imaging (iGE-EPI) sequence for multiplanar magnetic resonance temperature imaging (MRTI) to monitor intracerebral thermal treatment three-dimensionally using multielement ultrasound applicators.MATERIALS AND METHODS: Transmissible venereal tumor (TVT) fragments were injected into the right cerebral hemisphere of five do

Dosimeter gel and MR imaging for verification of calculated dose distributions in clinical radiation therapy

A dosimeter gel, based on an agarose gel infused with a ferrous sulphate solution and evaluated in a magnetic resonance scanner, was used for complete verification of calculated dose distributions. Two standard treatment procedures, treatment of cancer in the urinary bladder and treatment of breast cancer after modified radical mastectomy, were examined using pixel-by-pixel and dose volume histogr

Blind Source Separation of Speech Mixtures using a Simple and Computationally Efficient Time- Frequency Approach

A very simple and extremely computationally efficient algorithm for blind separation of two speech sources from two mixtures is presented in this paper. The algorithm exploits the approximate W-disjoint orthogonality of speech signals and assumes specific sensors (microphones) setting that allows the sources to possess a feature we call cross high-low diversity. Two sources are said to be cross hi

Distinguishing True and False Source Locations when Localizing Multiple Concurrent Speech Sources

A permutation problem arises in the case of locating multiple speech sources using several sensor arrays in the far field. The intersection of different direction of arrival (DOA) estimates between sensor arrays leads to a set of real source locations as well as a set of false intersections. This paper presents a novel method for pairing DOA estimates from different sensor arrays, resulting in the

Convection-dominated dispersion regime in wide-bore chromatography : A transport-based approach to assess the occurrence of slip flows in microchannels

This article develops the theoretical analysis of transport and dispersion phenomena in wide-bore chromatography at values of the Peclet number Pe beyond the upper bound of validity of the Taylor-Aris theory. It is shown that for Poiseuille flows in cylindrical capillaries the average residence time grows logarithmically with the Peclet number, while the variance of the outlet chromatogram scales

On the modelling of time-interleaved sequential lamination micromixers

We develop a novel and simple theoretical model of time-interleaved sequential lamination micromixers that improves the model proposed by Nguyen and coworkers (Microfluid Nanofluid 1:373-375, 2005a, Lab Chip 5:1320-1326, b, J Phys Conf Ser 34:136-141, 2006) based on the Taylor-Aris dispersion theory. The Nguyen model takes into account the non uniform structure of the velocity profile through an e

A new automatic algorithm for quantification of myocardial infarction imaged by late gadolinium enhancement cardiovascular magnetic resonance : Experimental validation and comparison to expert delineations in multi-center, multi-vendor patient data

Background: Late gadolinium enhancement (LGE) cardiovascular magnetic resonance (CMR) using magnitude inversion recovery (IR) or phase sensitive inversion recovery (PSIR) has become clinical standard for assessment of myocardial infarction (MI). However, there is no clinical standard for quantification of MI even though multiple methods have been proposed. Simple thresholds have yielded varying re

Changes in attitudes, intended behaviour, and mental health literacy in the Swedish population 2009–2014 : an evaluation of a national antistigma programme

Objective: Public stigma of mental illness is still a major problem where numerous population studies during the last decade have mainly shown no improvements. A Swedish national antistigma campaign has been running 2010–2014. The aim of this study was to investigate changes in public stigma during this period as compared to baseline in 2009. Methods: Yearly population surveys were made between 20

Media Scandals and Emotional Expression

Media scandals is one of the areas within the media field with high passion potential. The emotions within politics, that otherwise may be covered by rational arguments and cultural codes, are often in full bloom when a scandal takes place on the political scene (which as we know is a mediated scene). However, after a few decades of media scandal-research, a scientific convention seems to have ari

Environmental factors in the etiology of type 1 diabetes, celiac disease, and narcolepsy

The etiology of human leukocyte antigen (HLA)-associated organ-specific autoimmune diseases is incomplete. In type 1 diabetes and celiac disease, the strongest associations are with the HLA-DR3-DQ2 and DR4-DQ8 haplotypes, whereas the DQB1*06:02 allele has a strong negative association. In contrast, narcolepsy, especially as recently triggered by the Pandemrix® H1N1 vaccine (GlaxoKlineSmith (GSK),

Feedback architectures to regulate flux of components in artificial gene networks

This paper focuses on the regulation of RNA production for in vitro synthetic gene networks. We consider the problem of matching the production rate of several RNA species concurrently transcribed to form RNA complexes. We design regulatory feedback loops based on two schemes: negative auto-regulation (which can minimize the potentially harmful amount of molecules not used to form products) and cr

The amino-terminal phosphorylation sites of C-MYC are frequently mutated in Burkitt's lymphoma lines but not in mouse plasmacytomas and rat immunocytomas

We sequenced the region encoding the amino-terminal phosphorylation sites of C-MYC in the Ig/MYC translocation-carrying Burkitt lymphomas (BL), mouse plasmacytomas (MPC) and rat immunocytomas (RIC). Mutations affecting the Thr-58 codon or the immediate flanking region were found in seven of the 10 in vitro propagated BL lines. No mutations were found in any of the eight BL biopsies analysed. Germ-

Hypersomy of chromosome 15 with retrovirally rearranged c-myc, loss of germline c-myc and IgK/c-myc juxtaposition in a macrophage-monocytic tumour line

From a lymphoid tumour induced by 7,12-dimethylbenz-[a]-anthracene (DMBA) + methyl-N-nitrose-N-urea (MNU) in an [AKR Rb(6.15) x CBAT6T6]F1 mouse, a macrophage- monocyte line (KT-10) was isolated. Following ethyl methanesulfonate (EMS) treatment, a bromodeoxyuridine (BUdR) resistant subline was selected. Serial propagation of this line in vitro in the presence of BUdR (28 months) with periodic cyto