5,188 research outputs found
Observing the Spontaneous Breakdown of Unitarity
During the past decade, the experimental development of being able to create
ever larger and heavier quantum superpositions has brought the discussion of
the connection between microscopic quantum mechanics and macroscopic classical
physics back to the forefront of physical research. Under equilibrium
conditions this connection is in fact well understood in terms of the mechanism
of spontaneous symmetry breaking, while the emergence of classical dynamics can
be described within an ensemble averaged description in terms of decoherence.
The remaining realm of individual-state quantum dynamics in the thermodynamic
limit was addressed in a recent paper proposing that the unitarity of quantum
mechanical time evolution in macroscopic objects may be susceptible to a
spontaneous breakdown. Here we will discuss the implications of this theory of
spontaneous unitarity breaking for the modern experiments involving truly
macroscopic Schrodinger cat states.Comment: 4 pages, no figure
Chemokine blockade: a new era in the treatment of rheumatoid arthritis?
Blockade of chemokines or chemokine receptors is emerging as a new potential treatment for various immune-mediated conditions. This review focuses on the therapeutic potential in rheumatoid arthritis, based on studies in animal models and patients. Several knockout models as well as in vivo use of chemokine antagonists are discussed. Review of these data suggests that this approach might lead to novel therapeutic strategies in rheumatoid arthritis and other chronic inflammatory disorders
Perceived Impact of the Youth Enterprise Development Fund on the Youth Towards the Establishment of Small Scale Rural Enterprises in Turbo Division, Uasin-gishu County, Kenya
The inception of the Youth Enterprise Development Fund has seen the rise of youth groups in rural areas. This paper is thus aimed at understanding the impact of the fund towards the youth establishment of small scale enterprises in Turbo Division. A descriptive research design was used in this paper. Data was collected using focused group discussion and self-administered questionnaires thus they were administered to the selected youth groups found in selected parts of the Turbo Division. Purposive technique was used in the specific youth of aged bracket 18 year to 35 years. Further, purposive and stratified sampling techniques were used in targeted youth groups. The sample size used was 147 drawn from Turbo Division. The salient findings of the study are that indeed the youth joined the small scale enterprises to obtain benefits through collaborative efforts, to gain and obtain skills and experiences, obtaining start-up capital and finally due to the unemployment. Moreover, impact made by the fund on individual life included; promoting togetherness, promoting income and sustained livelihoods thus improved economic statues, and eventually enhanced skills and experience that led to acquiring of more skills by joining polytechnics. Furthermore the fund had enhanced group development and participation. It is recommended that there should be enhanced youth group sustainability towards proper utilization of the fund
Stimulation of beta-adrenergic receptors of S49 lymphoma cells redistributes the alpha subunit of the stimulatory G protein between cytosol and membranes.
The chiral phase transition in charge ordered 1T-TiSe2
It was recently discovered that the low temperature, charge ordered phase of
1T-TiSe2 has a chiral character. This unexpected chirality in a system
described by a scalar order parameter could be explained in a model where the
emergence of relative phase shifts between three charge density wave components
breaks the inversion symmetry of the lattice. Here, we present experimental
evidence for the sequence of phase transitions predicted by that theory, going
from disorder to non-chiral and finally to chiral charge order. Employing X-ray
diffraction, specific heat, and electrical transport measurements, we find that
a novel phase transition occurs ~7 K below the main charge ordering transition
in TiSe2, in agreement with the predicted hierarchy of charge ordered phases.Comment: 5 pages, 3 figures; includes additional experimental and theoretical
results; fixed typo
Exchange-mediated, nonlinear, out-of-plane magnetic field dependence of the ferromagnetic vortex gyrotropic mode frequency driven by core deformation
We have performed micromagnetic simulations of low-amplitude gyrotropic dynamics of magnetic vortices in the presence of spatially uniform out-of-plane magnetic fields. For disks having small lateral dimensions, we observe a frequency drop-off when approaching the disk's out-of-plane saturation field. This nonlinear frequency response is shown to be associated with a vortex core deformation driven by nonuniform demagnetizing fields that act on the shifted core. The deformation results in an increase in the average out-of-plane magnetization of the displaced vortex state (contrasting the effect of gyrofield-driven deformation at low field), which causes the exchange contribution to the vortex stiffness to switch from positive to negative. This generates an enhanced reduction of the core stiffness at high field, leading to a nonlinear field dependence of the gyrotropic mode frequency
Quantitative Impact Evaluation of the WINNN Programme – Summary Report: Operations Research and Impact Evaluation
This report presents the results of the quantitative impact evaluation of the Working to Improve Nutrition in Northern Nigeria (WINNN) programme. The impact evaluation is conducted by the Operations Research and Impact Evaluation (ORIE) project. ORIE is responsible for undertaking operations research and assessing the impact of the WINNN programme and it is led by Oxford Policy Management (OPM) and implemented in collaboration with other institutions.UK Department for International Developmen
Chirality and Orbital Order in Charge Density Waves
We show that the recently observed chirality in the charge ordered phase of
TiSe2 can be understood as a form of orbital ordering. The microscopic
mechanism driving the transition between the novel chiral state and the
non-chiral charge density wave is discussed, and shown to be of a general form,
thus allowing for a broad class of materials to display this type of orbitally
ordered chiral charge density wave.Comment: 4 pages, 4 figure
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