30,843 research outputs found
Evolution of breast cancer therapeutics: Breast tumour kinase’s role in breast cancer and hope for breast tumour kinase targeted therapy
This is an open access article distributed under the terms of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/). © 2014 Baishideng Publishing Group Inc.There have been significant improvements in the detection and treatment of breast cancer in recent decades. However, there is still a need to develop more effective therapeutic techniques that are patient specific with reduced toxicity leading to further increases in patients’ overall survival; the ongoing progress in understanding recurrence, resistant and spread also needs to be maintained. Better understanding of breast cancer pathology, molecular biology and progression as well as identification of some of the underlying factors involved in breast cancer tumourgenesis and metastasis has led to the identification of novel therapeutic targets. Over a number of years interest has risen in breast tumour kinase (Brk) also known as protein tyrosine kinase 6; the research field has grown and Brk has been described as a desirable therapeutic target in relation to tyrosine kinase inhibition as well as disruption of its kinase independent activity. This review will outline the current “state of play” with respect to targeted therapy for breast cancer, as well as discussing Brk’s role in the processes underlying tumour development and metastasis and its potential as a therapeutic target in breast cancer
Trade Liberalisation Policies, Intra-regional Trade and Opportunities for Sustainable Agricultural Development
Many of the Near East (NE) countries are currently opening their agricultural markets at three distinct but interacting levels: unilateral liberalisation, regional integration schemes and multilateral trade liberalisation. These changes hold important implications for intra- and extra-regional trade, use of agricultural resources and sustainability of agricultural development in the NE countries. Unilaterally, and since the late 1980s, most countries of the region have liberalised their agriculture sectors by eliminating or reducing input subsidies, removing or reducing guaranteed producer prices, reducing the number of subsidised commodities and liberalising the exchange rate and the trade regime. Most of the implicit and explicit subsidies for agricultural inputs and outputs were withdrawn. However, some of the NE countries were able to continue supporting agriculture mainly for food security reasons. Experiences showed that domestic reform is necessary but not sufficient condition for economic growth.
Frustrated Metastable Behavior of Magnetic and Transport Properties in Charge Ordered La1-xCaxMnO3+d Manganites
We have studied the effect of metastable, irreversibility induced by repeated
thermal cycles on the electric transport and magnetization of polycrystalline
samples of La1-xCaxMnO3 (0.48\leq x \leq 0.55) close to charge ordering. With
time and thermal cycling (T<300 K) there is an irreversible transformation of
the low-temperature phase from a partially ferromagnetic and metallic to one
that is less ferromagnetic and highly resistive for the composition close to
charge ordering (x=050 and 0.52). Irrespective of the actual ground state of
the compound, the effect of thermal cycling is towards an increase of the
amount of the insulating phase. We have observed the magnetic relaxation in the
metastable state and also the revival of the metastable state (in a relaxed
sample) due to high temperature thermal treatment. We observed changes in the
resistivity and magnetization as the revived metastable state is cycled. The
time changes in the magnetization are logarithmic in general and activation
energies are consistent with those expected for electron transfer between Mn
ions. Changes induced by thermal cycling can be inhibited by applying magnetic
field. These results suggest that oxygen non-stoichiometry results in
mechanical strains in this two-phase system, leading to the development of
frustrated metastable states which relax towards the more stable charge-ordered
and antiferromagnetic microdomains. Our results also suggest that the growth
and coexistence of phases gives rise to microstructural tracks and strain
accommodation, producing the observed irreversibility.Comment: 13 Pages, 10 Figure
Beating the One-half Limit of Ancilla-free Linear Optics Bell Measurements
We show that optically encoded two-qubit Bell states can be unambiguously
discriminated with a success probability of more than 50% in both single-rail
and dual-rail encodings by using active linear-optical resources that include
Gaussian squeezing operations. These results are in contrast to the well-known
upper bound of 50% for unambiguous discrimination of dual-rail Bell states
using passive, static linear optics and arbitrarily many vacuum modes. We
present experimentally feasible schemes that improve the success probability to
64.3% in dual-rail and to 62.5% in single-rail for a uniform random
distribution of Bell states. Conceptually, this demonstrates that neither
interactions that induce nonlinear mode transformations (such as Kerr
interactions) nor auxiliary entangled photons are required to go beyond the
one-half limit. We discuss the optimality of our single-rail scheme, and talk
about an application of our dual-rail scheme in quantum communication.Comment: 4+5 pages, 4 figure
Length-scale cascade and spread rate of atomizing planar liquid jets
The primary breakup of a planar liquid jet is explored via direct numerical
simulation (DNS) of the incompressible Navier-Stokes equation with level-set
and volume-of-fluid interface capturing methods. PDFs of the local radius of
curvature and the local cross-flow displacement of the liquid-gas interface are
evaluated over wide ranges of the Reynolds number (), Weber number (),
density ratio and viscosity ratio. The temporal cascade of liquid-structure
length scales and the spread rate of the liquid jet during primary atomization
are analyzed. The formation rate of different surface structures, e.g. lobes,
ligaments and droplets, are compared for different flow conditions and are
explained in terms of the vortex dynamics in each atomization domain that we
identified recently. With increasing , the average radius of curvature of
the surface decreases, the number of small droplets increases, and the cascade
and the surface area growth occur at faster rates. The spray angle is mainly
affected by and density ratio, and is larger at higher , at higher
density ratios, and also at lower . The change in the spray spread rate
versus is attributed to the angle of ligaments stretching from the jet
core, which increases as decreases. Gas viscosity has negligible effect on
both the droplet-size distribution and the spray angle. Increasing the
wavelength-to-sheet-thickness ratio, however, increases the spray angle and the
structure cascade rate, while decreasing the droplet size. The smallest length
scale is determined more by surface tension and liquid inertia than by the
liquid viscosity, while gas inertia and liquid surface tension are the key
parameters in determining the spray angle.Comment: Submitted for publication to International Journal of Multiphase
Flow. 37 pages; 33 figure
Understanding liquid-jet atomization cascades via vortex dynamics
Temporal instabilities of a planar liquid jet are studied using direct
numerical simulation (DNS) of the incompressible Navier-Stokes equations with
level-set (LS) and volume-of-fluid (VoF) surface tracking methods.
contours are used to relate the vortex dynamics to the surface dynamics at
different stages of the jet breakup, namely, lobe formation, lobe perforation,
ligament formation, stretching, and tearing. Three distinct breakup mechanisms
are identified in the primary breakup, which are well categorized on the
parameter space of gas Weber number () versus liquid Reynolds number
(). These mechanisms are analyzed here from a vortex dynamics
perspective. Vortex dynamics explains the hairpin formation, and the
interaction between the hairpins and the Kelvin-Helmholtz (KH) roller explains
the perforation of the lobes, which is attributed to the streamwise overlapping
of two oppositely-oriented hairpin vortices on top and bottom of the lobe. The
formation of corrugations on the lobe front edge at high is also related
to the location and structure of the hairpins with respect to the KH vortex.
The lobe perforation and corrugation formation are inhibited at low and
low due to the high surface tension and viscous forces, which damp the
small scale corrugations and resist hole formation. Streamwise vorticity
generation - resulting in three-dimensional instabilities - is mainly caused by
vortex stretching and baroclinic torque at high and low density ratios,
respectively. Generation of streamwise vortices and their interaction with
spanwise vortices produce the liquid structures seen at various flow
conditions. Understanding the liquid sheet breakup and the related vortex
dynamics are crucial for controlling the droplet size distribution in primary
atomization.Comment: Submitted for publication in Journal of Fluid Mechanics. 56 pages; 52
figure
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