364 research outputs found
Microwave saturation of the Rydberg states of electrons on helium
We present measurements of the resonant microwave excitation of the Rydberg
energy levels of surface state electrons on superfluid helium. The temperature
dependent linewidth agrees well with theoretical predictions and is very small
below 300 mK. Absorption saturation and power broadening were observed as the
fraction of electrons in the first excited state was increased to 0.49, close
to the thermal excitation limit of 0.5. The Rabi frequency was determined as a
function of microwave power. The high values of the ratio of the Rabi frequency
to linewidth confirm this system as an excellent candidate for creating qubits.Comment: 4 pages, 4 figure
Magnetoresistance of nondegenerate quantum electron channels formed on the surface of superfluid helium
Transport properties of quasi-one-dimensional nondegenerate quantum wires
formed on the surface of liquid helium in the presence of a normal magnetic
field are studied using the momentum balance equation method and the memory
function formalism. The interaction with both kinds of scatterers available
(vapor atoms and capillary wave quanta) is considered. We show that unlike
classical wires, quantum nondegenerate channels exhibit strong
magnetoresistance which increases with lowering the temperature.Comment: 8 pages, 7 figure
The place of strategic environmental assessment in the privatised electricity industry
The private sector has given relatively little attention to the emergence of strategic environmental assessment (SEA); even recently privatised utilities, where SEA might be deemed particularly appropriate, and whose activities are likely to fall within the scope of the European Union SEA Directive, have shown less interest than might be expected. However, the global trend towards the privatisation of state-owned enterprises makes the adaptation of SEA towards these industries all the more pressing. This paper addresses the place that SEA might take within the electricity sector, taking the privatised UK electricity industry as an example. Particular challenges are posed by the radical restructuring of the industry, designed to introduce competitive behaviour, making the development of comprehensive SEA processes problematic, and requiring SEA to be placed in the context of corporate environmental policy and objectives.</p
The microRNA-29 family in cartilage homeostasis and osteoarthritis
MicroRNAs have been shown to function in cartilage development and homeostasis, as well as in progression of osteoarthritis. The objective of the current study was to identify microRNAs involved in the onset or early progression of osteoarthritis and characterise their function in chondrocytes. MicroRNA expression in mouse knee joints post-DMM surgery was measured over 7 days. Expression of miR-29b-3p was increased at day 1 and regulated in the opposite direction to its potential targets. In a mouse model of cartilage injury and in end-stage human OA cartilage, the miR-29 family were also regulated. SOX9 repressed expression of miR-29a-3p and miR-29b-3p via the 29a/b1 promoter. TGFβ1 decreased expression of miR-29a, b and c (3p) in primary chondrocytes, whilst IL-1β increased (but LPS decreased) their expression. The miR-29 family negatively regulated Smad, NFκB and canonical WNT signalling pathways. Expression profiles revealed regulation of new WNT-related genes. Amongst these, FZD3, FZD5, DVL3, FRAT2, CK2A2 were validated as direct targets of the miR-29 family. These data identify the miR-29 family as microRNAs acting across development and progression of OA. They are regulated by factors which are important in OA and impact on relevant signalling pathways
Development, implementation, and evaluation of the Apollo model of pediatric rehabilitation service delivery
This article presents the experience of a rehabilitation program that un-
dertook the challenge to reorganize its services to address accessibility issues and im-
prove service quality. The context in which the reorganization process occurred, along
with the relevant literature justifying the need for a new service delivery model, and
an historical perspective on the planning; implementation; and evaluation phases of the
process are described. In the planning phase, the constitution of the working committee,
the data collected, and the information found in the literature are presented. Apollo, the
new service delivery model, is then described along with each of its components (e.g.,
community, group, and individual interventions). Actions and lessons learnt during the
implementation of each component are presented. We hope by sharing our experiences
that we can help others make informed decisions about service reorganization to im-
prove the quality of services provided to children with disabilities, their families, and
their communities
- …