686 research outputs found
Sexual abuse in adolescents - data from a psychiatric treatment centre for adolescents
No Abstract
Brane Resolution Through Fibration
We consider p-branes with one or more circular directions fibered over the
transverse space. The fibration, in conjunction with the transverse space
having a blown-up cycle, enables these p-brane solutions to be completely
regular. Some such circularly-wrapped D3-brane solutions describe flows from
SU(N)^3 N=2 theory, F_0 theory, as well as an infinite family of superconformal
quiver gauge theories, down to three-dimensional field theories. We discuss the
operators that are turned on away from the UV fixed points. Similarly, there
are wrapped M2-brane solutions which describe smooth flows from known
three-dimensional supersymmetric Chern-Simons matter theories, such as ABJM
theory. We also consider p-brane solutions on gravitational instantons, and
discuss various ways in which U-duality can be applied to yield other
non-singular solutions.Comment: 35 pages, additional referenc
Gauge Potential Formulations of the Spin Hall Effect in Graphene
Two different gauge potential methods are engaged to calculate explicitly the
spin Hall conductivity in graphene. The graphene Hamiltonian with spin-orbit
interaction is expressed in terms of kinematic momenta by introducing a gauge
potential. A formulation of the spin Hall conductivity is established by
requiring that the time evolution of this kinematic momentum vector vanishes.
We then calculated the conductivity employing the Berry gauge fields. We show
that both of the gauge fields can be deduced from the pure gauge field arising
from the Foldy-Wouthuysen transformations.Comment: Presentation improved. Published versio
The importance of the initial period of basal insulin titration in people with diabetes
Achieving target glycaemic control is essential in people with diabetes to minimize the risk of long-term complications, and many people with type 2 diabetes will ultimately require basal insulin (BI) therapy to achieve their individualized glycaemic targets. Usually, the first 12 weeks following initiation of BI therapy represents the period when the greatest dose increases and glycaemic reductions occur. Effective glycaemic control combined with minimizing the risk of hypoglycaemia is important to enable the achievement of glycaemic control in the longer term. However, substantial therapeutic inertia exists in clinical practice, both in initiation and up-titration of BI, owing to patient-, physician- and healthcare system-related barriers, including fear of hypoglycaemia and the perception of a burdensome regimen. The more prolonged duration of action, reduced glycaemic variability and lower risk of hypoglycaemia seen with second-generation versus first-generation BI analogues may help alleviate patients' and physicians' concerns and facilitate titration. In turn, optimal BI titration and subsequent metabolic benefits may help improve therapy adherence and self-management. This review details the clinical implications of prompt titration of BI to achieve early glycaemic control, and the importance of minimizing hypoglycaemia risk within the initial titration period. Facilitation of patients' self-management of BI is also addressed
Magnetic-Dipole Spin Effects in Noncommutative Quantum Mechanics
A general three-dimensional noncommutative quantum mechanical system mixing
spatial and spin degrees of freedom is proposed. The analogous of the harmonic
oscillator in this description contains a magnetic dipole interaction and the
ground state is explicitly computed and we show that it is infinitely
degenerated and implying a spontaneous symmetry breaking. The model can be
straightforwardly extended to many particles and the main above properties are
retained. Possible applications to the Bose-Einstein condensation with
dipole-dipole interactions are briefly discussed.Comment: New references added, implications with Bose-Einstein condensationare
discussed and some portions of the manuscript rewritte
A Note on Einstein Sasaki Metrics in D \ge 7
In this paper, we obtain new non-singular Einstein-Sasaki spaces in
dimensions D\ge 7. The local construction involves taking a circle bundle over
a (D-1)-dimensional Einstein-Kahler metric that is itself constructed as a
complex line bundle over a product of Einstein-Kahler spaces. In general the
resulting Einstein-Sasaki spaces are singular, but if parameters in the local
solutions satisfy appropriate rationality conditions, the metrics extend
smoothly onto complete and non-singular compact manifolds.Comment: Latex, 13 page
Effective field theory of topological insulator and the Foldy-Wouthuysen transformation
Employing the Foldy-Wouthuysen transformation it is demonstrated
straightforwardly that the first and second Chern numbers are equal to the
coefficients of the 2+1 and 4+1 dimensional Chern-Simons actions which are
generated by the massive Dirac fermions coupled to the Abelian gauge fields. A
topological insulator model in 2+1 dimensions is discussed and by means of a
dimensional reduction approach the 1+1 dimensional descendant of the 2+1
dimensional Chern-Simons theory is presented. Field strength of the Berry gauge
field corresponding to the 4+1 dimensional Dirac theory is explicitly derived
through the Foldy-Wouthuysen transformation. Acquainted with it the second
Chern numbers are calculated for specific choices of the integration domain. A
method is proposed to obtain 3+1 and 2+1 dimensional descendants of the
effective field theory of the 4+1 dimensional time reversal invariant
topological insulator theory. Inspired by the spin Hall effect in graphene, a
hypothetical model of the time reversal invariant spin Hall insulator in 3+1
dimensions is proposed.Comment: 20 pages. Few corrections and Refs. adde
Berry effect in acoustical polarization transport in phononic crystals
We derive the semiclassical equations of motion of a transverse acoustical
wave packet propagating in a phononic crystal subject to slowly varying
perturbations. The formalism gives rise to Berry effect terms in the equations
of motion, manifested as the Rytov polarization rotation law and the
polarization-dependent Hall effect. We show that the formalism is also
applicable to the case of non-periodic inhomogeneous media, yielding explicit
expressions for the Berry effect terms.Comment: To appear in JETP Let
Dendritic cells loaded with killed breast cancer cells induce differentiation of tumor-specific cytotoxic T lymphocytes
BACKGROUND: Early clinical trials, mostly in the setting of melanoma, have shown that dendritic cells (DCs) expressing tumor antigens induce some immune responses and some clinical responses. A major difficulty is the extension to other tumors, such as breast carcinoma, for which few defined tumor-associated antigens are available. We have demonstrated, using both prostate carcinoma and melanoma as model systems, that DCs loaded with killed allogeneic tumor cell lines can induce CD8(+ )T cells to differentiate into cytotoxic T lymphocytes (CTLs) specific for shared tumor antigens. METHODS: The present study was designed to determine whether DCs would capture killed breast cancer cells and present their antigens to autologous CD4(+ )and CD8(+ )T cells. RESULTS: We show that killed breast cancer cells are captured by immature DCs that, after induced maturation, can efficiently present MHC class I and class II peptides to CD8(+ )and CD4(+ )T lymphocytes. The elicited CTLs are able to kill the target cells without a need for pretreatment with interferon gamma. CTLs can be obtained by culturing the DCs loaded with killed breast cancer cells with unseparated peripheral blood lymphocytes, indicating that the DCs can overcome any potential inhibitory effects of breast cancer cells. CONCLUSION: Loading DCs with killed breast cancer cells may be considered a novel approach to breast cancer immunotherapy and to identification of shared breast cancer antigens
A new cell primo-culture method for freshwater benthic diatom communities
A new cell primo-culture method was developed for the benthic diatom community isolated from biofilm sampled in rivers. The approach comprised three steps: (1) scraping biofilm from river pebbles, (2) diatom isolation
from biofilm, and (3) diatom community culture. With a view to designing a method able to stimulate the growth of diatoms, to limit the development of other microorganisms, and to maintain in culture a community similar to the original natural one, different factors were tested in step 3:
cell culture medium (Chu No 10 vs Freshwater “WC” medium modified), cell culture vessel, and time of culture. The results showed that using Chu No 10 medium in an Erlenmeyer flask for cell culture was the optimal method,
producing enough biomass for ecotoxicological tests as well as minimising development of other microorganisms. After 96 h of culture, communities differed from the original communities sampled in the two rivers studied.
Species tolerant of eutrophic or saprobic conditions were favoured during culture. This method of diatom community culture affords the opportunity to assess, in vitro, the effects of different chemicals or effluents (water samples andindustrial effluents) on diatom communities, as well as on diatom cells, from a wide range of perspectives
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