Research in the design of high-performance reconfigurable systems

An initial design for the Bit Processor (BP) referred to in prior reports as the Processing Element or PE has been completed. Eight BP's, together with their supporting random-access memory, a 64 k x 9 ROM to perform addition, routing logic, and some additional logic, constitute the components of a single stage. An initial stage design is given. Stages may be combined to perform high-speed fixed or floating point arithmetic. Stages can be configured into a range of arithmetic modules that includes bit-serial one or two-dimensional arrays; one or two dimensional arrays fixed or floating point processors; and specialized uniprocessors, such as long-word arithmetic units. One to eight BP's represent a likely initial chip level. The Stage would then correspond to a first-level pluggable module. As both this project and VLSI CAD/CAM progress, however, it is expected that the chip level would migrate upward to the stage and, perhaps, ultimately the box level. The BP RAM, consisting of two banks, holds only operands and indices. Programs are at the box (high-level function) and system level. At the system level initial effort has been concentrated on specifying the tools needed to evaluate design alternatives

Fairtrade, place and moral economy: between abstract ethical discourse and the moral experience of Northern Cape farmers

This paper explores the significance of the relationships and disjunctures between the global moral discourses of Fairtrade that are articulated through ethics of fairness in supply chains and the everyday moral experiences, discourses and practices of producers that shape moral economies in specific localities. Due to increased governance through universal codes, standards and certification, Fairtrade risks becoming an abstract ethical and regulatory tool, disconnected from the moral economies of those poor farmers it is intended to benefit. In response, the paper makes a case for a deeper understanding of the moral economies of farmers involved in Fairtrade networks and the ways in which these emerge out of moral experiences that are deeply embedded in local social and cultural relations. Through a case study of Eksteenskuil Agricultural Cooperative in South Africa’s Northern Cape, it seeks to demonstrate the importance of understanding the moral experiences of producers to better consider what is at stake for them, focusing on notions of cooperation, fairness and the ‘good farmer’, perceptions of community, and concerns with survival and self-sufficiency. The paper concludes that working in culturally-sensitive ways with producer communities and understanding how their local moral worlds are structured is vital in bridging the gap between abstract ethical discourses and the place-based moral experiences of producers, and to ensuring the effectiveness of Fairtrade initiatives

Verifying timestamps of occultation observation systems

We describe an image timestamp verification system to determine the exposure timing characteristics and continuity of images made by an imaging camera and recorder, with reference to Coordinated Universal Time (UTC). The original use was to verify the timestamps of stellar occultation recording systems, but the system is applicable to lunar flashes, planetary transits, sprite recording, or any area where reliable timestamps are required. The system offers good temporal resolution (down to 2 msec, referred to UTC) and provides exposure duration and interframe dead time information. The system uses inexpensive, off-the- shelf components, requires minimal assembly and requires no high-voltage components or connections. We also describe an application to load FITS (and other format) image files, which can decode the verification image timestamp. Source code, wiring diagrams and built applications are provided to aid the construction and use of the device.Comment: 10 pages, 7 figures, accepted to Publications of the Astronomical Society of Australia (PASA

Self-aligned 0.12mm T-gate In.53Ga.47As/In.52Al.48As HEMT Technology Utilising a Non Annealed Ohmic Contact Strategy

An InGaAs/InAlAs based HEMT structure, lattice matched to an InP substrate, is presented in which drive current and transconductance has been optimized through a double-delta doping strategy. Together with an increase in channel carrier density, this allows the use of a non-annealed ohmic contact process. HEMT devices with 120 nm standard and self-aligned T-gates were fabricated using the non-annealed ohmic process. At DC, self-aligned and standard devices exhibited transconductances of up to 1480 and 1100 mS/mm respectively, while both demonstrated current densities in the range 800 mA/mm. At RF, a cutoff frequency f/sub T/ of 190 GHz was extracted for the self-aligned device. The DC characteristics of the standard devices were then calibrated and modelled using a compound semiconductor Monte Carlo device simulator. MC simulations provide insight into transport within the channel and illustrate benefits over a single delta doped structure

Stability of Ca-montmorillonite hydrates: A computer simulation study

Classic simulations are used to study interlayer structure, swelling curves, and stability of Ca-montmorillonite hydrates. For this purpose, NPzzT$ and MuPzzT ensembles are sampled for ground level and given burial conditions. For ground level conditions, a double layer hydrate having 15.0 A of basal spacing is the predominant state for relative vapor pressures (p/po) ranging in 0.6-1.0. A triple hydrate counting on 17.9 A of interlaminar distance was also found stable for p/po=1.0. For low vapor pressures, the system may produce a less hydrated but still double layer state with 13.5 A or even a single layer hydrate with 12.2 A of interlaminar distance. This depends on the established initial conditions. On the other hand, the effect of burial conditions is two sided. It was found that it enhances dehydration for all vapor pressures except for saturation, where swelling is promoted.Comment: 8 pages, 9 figure

A comparison of intermediate and long-acting insulins in people with type 2 diabetes starting insulin: an observational database study

AimsInsulin is normally added to oral glucose-lowering drugs in people with type 2 diabetes when glycaemic control becomes suboptimal. We evaluated outcomes in people starting insulin therapy with neutral protamine Hagedorn (NPH), detemir, glargine or premixed insulins.MethodsInsulin-naïve people with type 2 diabetes (n = 8009), ≥ 35 years old, HbA(1c) ≥ 6.5% and begun on NPH (n = 1463), detemir (n = 357), glargine (n = 2197) or premix (n = 3992), were identified from a UK database of primary care records (The Health Improvement Network). Unadjusted and multivariate-adjusted analyses were conducted, with persistence of insulin therapy assessed by survival analysis.ResultsIn the study population (n = 4337), baseline HbA(1c) was 9.5 ± 1.6%, falling to 8.4 ± 1.5% over 12 months (change -1.1 ± 1.8%, p Discussion and conclusionIn routine clinical practice, people with type 2 diabetes commenced on NPH experienced a modest disadvantage in glycaemic control after 12 months compared with other insulins. When comparing the insulins, glargine achieved best HbA(1c) reduction, while premix showed greatest weight gain and the highest dose requirement, but had the best persistence of therapy.J. Gordon, R. D. Pockett, A. P. Tetlow, P. McEwan, P. D. Hom

A randomized study of autologous bone marrow–derived stem cells in pediatric cardiomyopathy

Background: Bone marrow mononuclear cell fraction has been used as therapy for dilated cardiomyopathy in adults. Although case series are reported, there are no randomized controlled studies in children. / Methods: We designed a randomized, crossover, controlled pilot study to determine safety and feasibility of intracoronary stem cell therapy in children. The primary safety end-point was freedom from death and transplantation or any complication that could be considered related to bone marrow injection or anesthesia (e.g., infection, malignancy, anaphylaxis, renal deterioration). Other end-points were magnetic resonance imaging measurements and N-terminal prohormone brain natriuretic peptide. Participants included 10 children (mean age 7.2 years; range, 2.2–14.1 years; 6 boys) with cardiomyopathy (New York Heart Association/Ross Classification II–IV). Patients were crossed over at 6 months. / Results: The original protocol was completed by 9 patients. The safety end-point was achieved in all. Ratio of the geometric means for treatment effect adjusting for baseline was assessed for end-diastolic and end-systolic volumes (EDV, ESV): 0.93 for EDV (95% confidence interval 0.88–0.99, p = 0.01), indicating EDV was on average 7% lower in patients after stem cell treatment, and 0.90 for ESV (95% confidence interval 0.82–1.00, p = 0.05), indicating ESV was on average 10% lower after stem cell treatment compared with placebo. The primary efficacy end-point ejection fraction was not met. / Conclusions: Bone marrow mononuclear cell therapy for cardiomyopathy is feasible and safe in children. Left ventricular volumes were significantly reduced 6 months after stem cell injection compared with placebo, which may reflect reverse remodeling