Apparatus for changing the orientation and velocity of a spinning body traversing a path Patent

Development of method and apparatus for spinning satellite about selected axis after reaching predetermined orientatio

Electron temperature in electrically isolated Si double quantum dots

Charge-based quantum computation can be attained through reliable control of single electrons in lead-less quantum systems. Single-charge transitions in electrically-isolated double quantum dots (DQD) realised in phosphorus-doped silicon can be detected via capacitively coupled single-electron tunnelling devices. By means of time-resolved measurements of the detector's conductance, we investigate the dots' occupancy statistics in temperature. We observe a significant reduction of the effective electron temperature in the DQD as compared to the temperature in the detector's leads. This sets promises to make isolated DQDs suitable platforms for long-coherence quantum computation.Comment: 4 pages, 3 figure

Multiple structural alignment for distantly related all b structures using TOPS pattern discovery and simulated annealing

Topsalign is a method that will structurally align diverse protein structures, for example, structural alignment of protein superfolds. All proteins within a superfold share the same fold but often have very low sequence identity and different biological and biochemical functions. There is often signi®cant structural diversity around the common scaffold of secondary structure elements of the fold. Topsalign uses topological descriptions of proteins. A pattern discovery algorithm identi®es equivalent secondary structure elements between a set of proteins and these are used to produce an initial multiple structure alignment. Simulated annealing is used to optimize the alignment. The output of Topsalign is a multiple structure-based sequence alignment and a 3D superposition of the structures. This method has been tested on three superfolds: the b jelly roll, TIM (a/b) barrel and the OB fold. Topsalign outperforms established methods on very diverse structures. Despite the pattern discovery working only on b strand secondary structure elements, Topsalign is shown to align TIM (a/b) barrel superfamilies, which contain both a helices and b strands

Evaluation of the usefulness of a computer‐based learning program to support student learning in pharmacology

This study aims to evaluate the effectiveness of a computer‐based teaching program in supporting and enhancing traditional teaching methods. The program covers the pharmacology of inflammation and has been evaluated with a group of second‐year medical students at a UK university. The study assessed subject‐specific knowledge using a pre‐ and post‐test and surveyed, by questionnaire, students’ perceptions of the usefulness of the program to support learning before and after use. The use of computers for learning amongst this cohort of students was widespread. The results demonstrated an increase in students ‘ knowledge of the pharmacology of inflammation, coupled with a positive attitude towards the CBL program they had used and the advantages that this mode of study may provide in enabling students to manage their own learning. However, students did not feel that the program could substitute for traditional teaching (lectures)

Analysis of self-oscillating DC-DC resonant power converters using a hysteretic relay

The paper presents a technique for exciting resonant DC-DC converters in a self-oscillating manner. The analysis necessary to predict the behaviour of such converters is also given. The oscillation is based on the behaviour of a hysteretic relay with a negative hysteresis transition. Self-oscillating converters benefit from higher efficiency/higher power density than their non-self-oscillating counterparts as they can be operated closer to the tank resonant frequency. The self-oscillating mechanism presented here is also simple and cost effective to implement. A prototype converter is presented in order to verify the theoretical claims

SINDA/SINFLO computer routine, volume 1, revision A

The SINFLO package was developed to modify the SINDA preprocessor to accept and store the input data for fluid flow systems analysis and adding the FLOSOL user subroutine to perform the flow solution. This reduced and simplified the user input required for analysis of flow problems. A temperature calculation method, the flow-hybrid method which was developed in previous VSD thermal simulator routines, was incorporated for calculating fluid temperatures. The calculation method accuracy was improved by using fluid enthalpy rather than specific heat for the convective term of the fluid temperature equation. Subroutines and data input requirements are described along with user subroutines, flow data storage, and usage of the plot program

Optimal Quantum Circuits for General Two-Qubit Gates

In order to demonstrate non-trivial quantum computations experimentally, such as the synthesis of arbitrary entangled states, it will be useful to understand how to decompose a desired quantum computation into the shortest possible sequence of one-qubit and two-qubit gates. We contribute to this effort by providing a method to construct an optimal quantum circuit for a general two-qubit gate that requires at most 3 CNOT gates and 15 elementary one-qubit gates. Moreover, if the desired two-qubit gate corresponds to a purely real unitary transformation, we provide a construction that requires at most 2 CNOTs and 12 one-qubit gates. We then prove that these constructions are optimal with respect to the family of CNOT, y-rotation, z-rotation, and phase gates.Comment: 6 pages, 8 figures, new title, final journal versio

Charge Detection in Phosphorus-doped Silicon Double Quantum Dots

We report charge detection in degenerately phosphorus-doped silicon double quantum dots (DQD) electrically connected to an electron reservoir. The sensing device is a single electron transistor (SET) patterned in close proximity to the DQD. Measurements performed at 4.2K show step-like behaviour and shifts of the Coulomb Blockade oscillations in the detector's current as the reservoir's potential is swept. By means of a classical capacitance model, we demonstrate that the observed features can be used to detect single-electron tunnelling from, to and within the DQD, as well as to reveal the DQD charge occupancy.Comment: 4 pages, 3 figure

Energy and environmental burdens of organic and non-organic agriculture and horticulture

Production of 10 major commodities in England and Wales was studied using Life Cycle Analysis (LCA). Organic and non-organic (contemporary conventional) systems were compared. Organic production was generally less energy consuming, except for poultry meat, eggs and tomatoes. Environmental burdens, such as global warming potential or eutrophication were often greater per unit of production from organic than non-organic systems