403 research outputs found
Size Dependence of Static and Dynamic Magnetic Properties in Nanoscale Square Permalloy Antidot Arrays
Permalloy antidot arrays with different square hole sizes ( , , and ) have been fabricated by means of electron-beam lithography and lift-off techniques. The smaller square hole size results in enhanced remanence and reduced coercivity in the antidot array. Multiple resonance modes were clearly observed for the magnetic field applied normal to the array plane, and double uniform resonance modes occurred when the field deviated more than 30° from the normal to the plane. Two distinct dipolar field patterns with different orientations and magnitudes split the uniform resonance into double resonance modes. The double resonance modes show uniaxial in-plane anisotropy and the easy axes are orthogonal. The magnitude of the induced dipolar anisotropy remains almost constant with changes in the square hole size. The double resonance peaks move to low field with reduction of the square hole size
Therapeutic efficacy of an oncolytic adenovirus containing RGD ligand in minor capsid protein IX and Fiber, Δ24DoubleRGD, in an ovarian cancer model
Ovarian cancer is the leading cause of gynecological disease death despite advances in medicine. Therefore, novel strategies are required for ovarian cancer therapy. Conditionally replicative adenoviruses (CRAds), genetically modified as anti-cancer therapeutics, are one of the most attractive candidate agents for cancer therapy. However, a paucity of coxsackie B virus and adenovirus receptor (CAR) expression on the surface of ovarian cancer cells has impeded treatment of ovarian cancer using this approach.This study sought to engineer a CRAd with enhanced oncolytic ability in ovarian cancer cells, “Δ24DoubleRGD.” Δ24DoubleRGD carries an arginine-glycine-aspartate (RGD) motif incorporated into both fiber and capsid protein IX (pIX) and its oncolytic efficacy was evaluated in ovarian cancer. In vitro analysis of cell viability showed that infection of ovarian cancer cells with Δ24DoubleRGD leads to increased cell killing relative to the control CRAds. Data from this study suggested that not only an increase in number of RGD motifs on the CRAd capsid, but also a change in the repertoir of targeted integrins could lead to enhanced oncolytic potency of Δ24DoubleRGD in ovarian cancer cells in vitro. In an intraperitoneal model of ovarian cancer, mice injected with Δ24DoubleRGD showed, however, a similar survival rate as mice treated with control CRAds
Community College Presidents and Campus Safety: Perspectives on Critical Issues
Community college presidents must understand the phenomenon of campus safety. For this mixed-methods study, community college presidents in one state were surveyed, and three presidents from the same community college system participated in in-depth interviews. Descriptive statistics measured the levels community college presidents’ knowledge and perceptions on campus safety. The in-depth interviews provided a deeper understanding of the connections between community college presidents and campus safety.
Overall, the results show that campus safety is important to community college presidents, who believe that, overall, their institutions are safe. We found that community college presidents believe they should be proactive and reinforce values that promote and prioritize campus safety, follow regulations, and provide sufficient resources to ensure campus safety measures. However, inadequate funding also plays a role in what can be allocated, and community college presidents voiced that they were concerned about promoting safety in the face of declining budgets and resources
Magnetism in Cr-doped ZnS: Density-functional theory studies
We investigated the magnetism and aggregation trends in cubic Zn1-xCrxS using
the density-functional theory calculations.We demonstrate that all studied
configurations show ground state half-metallic ferromagnetism (HMF); and Cr
impurities are energetically favorable to planar cluster into delta-doping
structures. The single-layer delta-doping structures of Zn0.75Cr0.25S and
Zn0.875Cr0.125S show ferromagnetic stabilization energies (\Delta E_AF) of
0.551 and 0.561 eV/Cr-Cr pair, respectively. The half-layer delta-doping
structure of Zn0.875Cr0.125S and double-layer delta-doping structure of
Zn0.75Cr0.25S show \Delta E_AF of 0.394 and 0.166 eV/Cr-Cr pair, respectively.
Furthermore, our studies indicate that the cubic ZnS/CrS heterostructure, one
extreme situation of the delta-doping structure, also shows ground state HMF.
The origin of HMF is discussed using a simple crystal field model. Finally, we
anticipate the potential spintronics application of Zn1-xCrxS.Comment: 13 pages, 4 figure
Topological Defects and Non-homogeneous Melting of Large 2D Coulomb Clusters
The configurational and melting properties of large two-dimensional clusters
of charged classical particles interacting with each other via the Coulomb
potential are investigated through the Monte Carlo simulation technique. The
particles are confined by a harmonic potential. For a large number of particles
in the cluster (N>150) the configuration is determined by two competing
effects, namely in the center a hexagonal lattice is formed, which is the
groundstate for an infinite 2D system, and the confinement which imposes its
circular symmetry on the outer edge. As a result a hexagonal Wigner lattice is
formed in the central area while at the border of the cluster the particles are
arranged in rings. In the transition region defects appear as dislocations and
disclinations at the six corners of the hexagonal-shaped inner domain. Many
different arrangements and type of defects are possible as metastable
configurations with a slightly higher energy. The particles motion is found to
be strongly related to the topological structure. Our results clearly show that
the melting of the clusters starts near the geometry induced defects, and that
three different melting temperatures can be defined corresponding to the
melting of different regions in the cluster.Comment: 7 pages, 11 figures, submitted to Phys. Rev.
Quantum correlations and synchronization measures
The phenomenon of spontaneous synchronization is universal and only recently
advances have been made in the quantum domain. Being synchronization a kind of
temporal correlation among systems, it is interesting to understand its
connection with other measures of quantum correlations. We review here what is
known in the field, putting emphasis on measures and indicators of
synchronization which have been proposed in the literature, and comparing their
validity for different dynamical systems, highlighting when they give similar
insights and when they seem to fail.Comment: book chapter, 18 pages, 7 figures, Fanchini F., Soares Pinto D.,
Adesso G. (eds) Lectures on General Quantum Correlations and their
Applications. Quantum Science and Technology. Springer (2017
Evaluation of adenovirus capsid labeling versus transgene expression
Adenoviral vectors have been utilized for a variety of gene therapy applications. Our group has incorporated bioluminescent, fluorographic reporters, and/or suicide genes within the adenovirus genome for analytical and/or therapeutic purposes. These molecules have also been incorporated as capsid components. Recognizing that incorporations at either locale yield potential advantages and disadvantages, our report evaluates the benefits of transgene incorporation versus capsid incorporation. To this end, we have genetically incorporated firefly luciferase within the early region 3 or at minor capsid protein IX and compared vector functionality by means of reporter readout
Transition Between Ground State and Metastable States in Classical 2D Atoms
Structural and static properties of a classical two-dimensional (2D) system
consisting of a finite number of charged particles which are laterally confined
by a parabolic potential are investigated by Monte Carlo (MC) simulations and
the Newton optimization technique. This system is the classical analog of the
well-known quantum dot problem. The energies and configurations of the ground
and all metastable states are obtained. In order to investigate the barriers
and the transitions between the ground and all metastable states we first
locate the saddle points between them, then by walking downhill from the saddle
point to the different minima, we find the path in configurational space from
the ground state to the metastable states, from which the geometric properties
of the energy landscape are obtained. The sensitivity of the ground-state
configuration on the functional form of the inter-particle interaction and on
the confinement potential is also investigated
An Unified Approach To Pseudo Scalar Meson Photoproductions Off Nucleons In The Quark Model
An unified approach to the pseudo scalar meson (, and )
photoproduction off nucleons are presented. It begins with the low energy QCD
Lagrangian, and the resonances in the s- and u- channels are treated in the
framework of the quark model
The duality hypothesis is imposed to limit the number of the t-channel
exchanges. The CGLN amplitudes for each reaction are evaluated, which include
both proton and neutron targets. The important role by the S-wave resonances in
the second resonance region is discussed, it is particularly important for the
and photoproductions.Comment: 31 pages in Latex fil
Cross section for the H + H2O abstraction reaction: experiment and theory
The absolute value of the cross section for the abstraction reaction between fast H atoms and H2O has
been determined experimentally at a mean collision energy of 2.46 eV. The OH population distribution
at the same mean energy has also been determined. The new measurements are compared with state-ofthe-
art quantum mechanical and quasiclassical scattering calculations on the most recently developed
potential energy surface
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