Search results for "DOMAIN"
showing 10 items of 2485 documents
Smoothed Particle ElectroMagnetics: A mesh-free solver for transients
2006
AbstractIn this paper an advanced mesh-free particle method for electromagnetic transient analysis, is presented. The aim is to obtain efficient simulations by avoiding the use of a mesh such as in the most popular grid-based numerical methods. The basic idea is to obtain numerical solutions for partial differential equations describing the electromagnetic problem by using a set of particles arbitrarily placed in the problem domain. The mesh-free smoothed particle hydrodynamics method has been adopted to obtain numerical solution of time domain Maxwell's curl equations. An explicit finite difference scheme has been employed for time integration. Details about the numerical treatment of elec…
SPECIAL SPLINES OF HYPERBOLIC TYPE FOR THE SOLUTIONS OF HEAT AND MASS TRANSFER 3-D PROBLEMS IN POROUS MULTI-LAYERED AXIAL SYMMETRY DOMAIN
2017
In this paper we study the problem of the diffusion of one substance through the pores of a porous multi layered material which may absorb and immobilize some of the diffusing substances with the evolution or absorption of heat. As an example we consider circular cross section wood-block with two layers in the radial direction. We consider the transfer of heat process. We derive the system of two partial differential equations (PDEs) - one expressing the rate of change of concentration of water vapour in the air spaces and the other - the rate of change of temperature in every layer. The approximation of corresponding initial boundary value problem of the system of PDEs is based on the cons…
Modulation of Hedgehog target gene expression by the Fused serine-threonine kinase in wing imaginal discs
1998
0925-4773 doi: DOI: 10.1016/S0925-4773(98)00130-0; The Fused (Fu) serine–threonine kinase and the Suppressor of fused (Su(fu)) product are part of the Hedgehog (Hh) signalling pathway both in embryos and in imaginal discs. In wing imaginal discs, the Hh signal induces Cubitus interruptus (Ci) accumulation and activates patched (ptc) and decapentaplegic (dpp) expression along the anterior/posterior (A/P) boundary. In this paper, we have examined the role of the Fu and Su(fu) proteins in the regulation of Hh target gene expression in wing imaginal discs, by using different classes of fu alleles and an amorphic Su(fu) mutation. We show that, at the A/P boundary, Fu kinase activity is involved …
High Lymph Vessel Density and Expression of Lymphatic Growth Factors in Peritoneal Endometriosis
2012
To investigate the occurrence of lymph vessels and lymphangiogenic growth factors in peritoneal lesions, we performed immunohistochemical staining of peritoneal lesions of 37 patients with antibodies against podoplanin (D2-40), lymphatic vessel endothelial hyaluronan receptor 1 (LYVE-1), prospero homeobox protein 1 (Prox-1), vascular epithelial growth factor (VEGF)-C/VEGF-D. Overall, 10 lesions were double stained against D2-40 and von Willebrand factor. The lymph vessel density in peritoneal lesion was significantly higher in comparison with healthy peritoneum. All lymph vessel makers could be detected, whereby the lymph vessel density of LYVE-1- and Prox-1-positive lymph vessels was signi…
Transplantation of low dose CD34+KDR+ cells promotes vascular and muscular regeneration in ischemic limbs.
2004
Hematopoietic progenitor cell transplantation can contribute to revascularization of ischemic tissues. Yet, the optimal cell population to be transplanted has yet to be determined. We have compared the therapeutic potential of two subsets of human cord blood CD34+ progenitors, either expressing the VEGF-A receptor 2 (KDR) or not. In serum-free starvation culture, CD34+KDR+ cells reportedly showed greater resistance to apoptosis and ability to release VEGF-A, as compared with CD34+KDR- cells. When injected into the hind muscles in immunodeficient SCIDbg mice subjected to unilateral ischemia, a low number (10(3)) of CD34+KDR+ cells improved limb salvage and hemodynamic recovery better than a …
Notch signalling is off and is uncoupled from HES1 expression in Ewing's sarcoma
2010
Notch can act as an oncogene or as a tumour suppressor and thus can either promote or inhibit tumour cell growth. To establish Notch status in Ewing's sarcoma family of tumours (ESFT), we investigated the Notch pathway by gene expression profiling meta-analysis or immunohistochemistry in samples obtained from 96 and 24 ESFT patients, respectively. We found that although Notch receptors were highly expressed, Notch did not appear to be active, as evidenced by the absence of Notch receptors in cell nuclei. In contrast, we show that Notch receptors known to be active in colon adenocarcinoma, hepatocarcinoma, and pancreatic carcinoma stain cell nuclei in these tumours. High expression of the No…
Pattern formation driven by cross–diffusion in a 2D domain
2012
Abstract In this work we investigate the process of pattern formation in a two dimensional domain for a reaction–diffusion system with nonlinear diffusion terms and the competitive Lotka–Volterra kinetics. The linear stability analysis shows that cross-diffusion, through Turing bifurcation, is the key mechanism for the formation of spatial patterns. We show that the bifurcation can be regular, degenerate non-resonant and resonant. We use multiple scales expansions to derive the amplitude equations appropriate for each case and show that the system supports patterns like rolls, squares, mixed-mode patterns, supersquares, and hexagonal patterns.
Domain structure of epitaxial SrRuO3 thin films
2005
Growth of multidomains in epitaxial thin-film oxides is known to have a detrimental effect on some functional properties, and, thus, efforts are done to suppress them. It is commonly accepted that optimal properties of the metallic and ferromagnetic $\mathrm{SrRu}{\mathrm{O}}_{3}$ (SRO) epitaxies can only be obtained if vicinal $\mathrm{SrTi}{\mathrm{O}}_{3}$ (001) (STO) substrates are used. It is believed that this results from the suppression of multidomain structure in the SRO film. Here we revise this important issue. Nanometric films of SRO have been grown on STO(001) vicinal substrates with miscut $({\ensuremath{\theta}}_{V})$ angles in the $\ensuremath{\sim}0.04\ifmmode^\circ\else\te…
Magnetization dynamics in polycrystalline Permalloy and epitaxial Co platelets observed by time-resolved photoemission electron microscopy
2009
We studied the dynamic magnetization response in rectangular polycrystalline Permalloy and also epitaxial Co structures (lateral sizes comprised tens of microns at a thickness of tens of nanometers) during the action of a magnetic field pulse, using time-resolved X-ray photoemission electron microscopy with a time resolution of 10 ps. In the case of Permalloy platelets the restoring torque that is necessary for the stroboscopic image acquisition is provided by the Landau flux closure structure representing a minimum of the free energy. We investigated the dynamic response of 90° Neel domain walls. The main results are: the maximum velocity of the domain wall is 1.5 × 104 m/s, the intrinsic …
Domain wall pinning in ultra-narrow electromigrated break junctions
2014
The study of magnetic domain walls in constrained geometries is an important topic, yet when dealing with extreme nanoscale magnetic systems artefacts can often dominate the measurements and obscure the effects of intrinsic magnetic origin. In this work we study the evolution of domain wall depinning in electromigrated ferromagnetic junctions which are both initially fabricated and subsequently tailored in-situ in clean ultra-high vacuum conditions. Carefully designed Ni(80)Fe(20) (Permalloy) notched half-ring structures are fabricated and investigated as a function of constriction width by tailoring the size of the contact using controlled in-situ electromigration. It is found that the dom…