On the elastic approximation to the vacancy formation energy in metals

Isotropic elastic continuum model application to calculate energy and entropy of vacancy formation in metal crystal

A survey of load methodologies for shuttle orbiter payloads

Loads methods currently being used to design shuttle orbiter payloads are summarized. Methods used for the design of payloads launched by expendable launch vehicles are described in historical perspective. Experiences gained from expendable launch vehicle payloads are used to develop methodologies for the space shuttle orbiter payloads. The objectives for the development of a new methodology for the shuttle payloads are to reduce the cost and schedule for the payload load analysis by decoupling the payload analysis from the launch vehicle to the maximum extent possible. Methods are described for payload member load estimation or obtaining upper bounds for dynamic loads, as well as load prediction or calculating actual transient member load time histories

Thermoelastic analysis of solar cell arrays and their material properties

Announced report discusses experimental test program in which five different solar cell array designs were evaluated by subjecting them to 60 thermal cycles from minus 190 deg to 0.0 deg. Results indicate that solder-coated cells combined with Kovar n-interconnectors and p-interconnectors are more durable under thermal loading than other configurations

Tests of the Rockwell Si:As Back-Illuminated Blocked-Impurity Band (BIBIB) detectors

Two arrays of Rockwell's Si:As back-illuminated blocked-impurity-band detectors were tested at the Max-Planck-Institute for Astronomy (MPIA) at low background and low temperature for possible use in the astronomical space experiment ISOPHOT. For these measurements special test equipment was put together. A cryostat was mechanically modified to accommodate the arrays and special peripheral electronics was added to a microprocessor system to drive the cold multiplexer and to acquire the output data. The first device, a 16x50 element array on a fan-out board was used to test individual pixels with a trans-impedance-amplifier at a photon background of 10(exp 8) Ph s(-1)cm(-2) and at temperatures of 2.7 to 4.4 K. The noise-equivalent-power NEP is in the range 5 - 7 x 10(exp -18) WHz(exp -1/2), the responsivity is less than or equal to 100 AW(exp -1)(f = 10 Hz). The second device was a 10x50 array including a cold readout electronics of switched FETs (SWIFET). Measurements of this array were done in a background range of 5 x 10(exp 5) to 5 x 10(exp 11) Ph s(exp-1)cm(exp-2) and at operating temperatures between 3.0 and 4.8 K. The NEP ranges from less than 10(exp -18) at the lowest background to 2 x 10(exp -16) WHz(exp -1/2) at the highest flux

Association of ANCA associated vasculitis and rheumatoid arthritis: a lesser recognized overlap syndrome

Background ANCA associated vasculitis (AAV) is an autoimmune disease with significant morbidity and mortality, in which diagnostic delay is associated with worse outcomes. AAV is rarely found in association with other immune mediated diseases. Early recognition of such overlaps enables more timely diagnosis and may impact on disease outcome. We reviewed cases of AAV in which there was an overlap with rheumatoid arthritis (RA). Methods We performed a retrospective analysis of our vasculitis database for patients who had a diagnosis of AAV and RA, and a literature search to find other reported cases of this overlap syndrome. Results We found six subjects who had a diagnosis of RA and developed AAV at a median of 10.5 years (range 4–43 years) after the diagnosis of RA. They had been treated with a mean of 2 disease modifying drugs (0–4) and all had evidence of renal involvement with median creatinine of 227 μmol/l (range 128–700 μmol/l). Only one had a diagnosis of granulomatosis with polyangiitis, while the rest had a clinical diagnosis of microscopic polyangiitis. Half of the patients had positive rheumatoid factor (RhF) at the time of vasculitis diagnosis, three had MPO-ANCA, one PR3-ANCA, and two had ANCA-negative pauci-immune vasculitis. Additionally, we found 29 other cases reported of this overlap, which also most frequently presented with vasculitic renal manifestations, and were frequently RhF positive at the time of AAV diagnosis. Conclusions AAV occurs in subjects with RA rarely, and often with significant delay from the first rheumatological manifestations. Renal involvement is commo

Optimal placement of excitations and sensors by simulated annealing

The optimal placement of discrete actuators and sensors is posed as a combinatorial optimization problem. Two examples for truss structures were used for illustration; the first dealt with the optimal placement of passive dampers along existing truss members, and the second dealt with the optimal placement of a combination of a set of actuators and a set of sensors. Except for the simplest problems, an exact solution by enumeration involves a very large number of function evaluations, and is therefore computationally intractable. By contrast, the simulated annealing heuristic involves far fewer evaluations and is best suited for the class of problems considered. As an optimization tool, the effectiveness of the algorithm is enhanced by introducing a number of rules that incorporate knowledge about the physical behavior of the problem. Some of the suggested rules are necessarily problem dependent

Sediment characterization in the ‘IJzermonding’ using empirical orthogonal functions: application to CASI

The erodability of mudflats is strongly determined by biophysical characteristics of sediments, such as silt, sand, benthic microalgae and water content. Mudflats are often large and inaccessible areas, leading to dangerous and time-consuming in situ measurement campaigns. Furthermore the collected point samples are unrepresentative for the spatial variability of these coastal systems. Airborne hyperspectral remote sensing is identified to be effective for the collection of a synoptic overview of biophysical characteristics of sediments in mudflats. An automated method for the classification of hyperspectral images acquired by the Compact Airborne Spectrographic Imager (CASI) is proposed. The method is based on a linear transformation of each spectrum in the hyperspectral cube. Comparable classification results are obtained using a standard classification method employed in hyperspectral image processing. The superiority of the proposed method lies in its robustness, computational requirements, repeatability, interpretability and objectiveness

A call for the aggressive treatment of oligometastatic and oligo-recurrent non-small cell lung cancer.

Metastatic non-small cell lung cancer (NSCLC) carries a dismal prognosis. Clinical evidence suggests the existence of an intermediate, or oligometastatic, state when metastases are limited in number and/or location. In addition, following initial curative therapy, many patients present with limited metastatic disease, or oligo-recurrence. Metastasis-directed, anti-cancer therapies may benefit these patients. A growing evidence-base supports the use of hypofractionated, image-guided radiotherapy (HIGRT) for a variety of malignant conditions including inoperable stage I NSCLC and many metastatic sites. When surgical resection is not possible, HIGRT offers an effective alternative for local treatment of limited metastatic disease. Early studies have produced promising results when HIGRT was delivered to all known sites of disease in patients with oligometastatic/oligo-recurrent NSCLC. In a population of patients formerly considered rapidly terminal, these studies report five year overall survival rates of 13-22%. HIGRT for metastatic NSCLC warrants further study. We call for large, intergroup, and even international randomized trials incorporating HIGRT and other metastasis-directed therapies into the treatment of patients with oligometastatic/oligo-recurrent NSCLC

Inclusion of neighboring base interdependencies substantially improves genome-wide prokaryotic transcription factor binding site prediction

Prediction of transcription factor binding sites is an important challenge in genome analysis. The advent of next generation genome sequencing technologies makes the development of effective computational approaches particularly imperative. We have developed a novel training-based methodology intended for prokaryotic transcription factor binding site prediction. Our methodology extends existing models by taking into account base interdependencies between neighbouring positions using conditional probabilities and includes genomic background weighting. This has been tested against other existing and novel methodologies including position-specific weight matrices, first-order Hidden Markov Models and joint probability models. We have also tested the use of gapped and ungapped alignments and the inclusion or exclusion of background weighting. We show that our best method enhances binding site prediction for all of the 22 Escherichia coli transcription factors with at least 20 known binding sites, with many showing substantial improvements. We highlight the advantage of using block alignments of binding sites over gapped alignments to capture neighbouring position interdependencies. We also show that combining these methods with ChIP-on-chip data has the potential to further improve binding site prediction. Finally we have developed the ungapped likelihood under positional background platform: a user friendly website that gives access to the prediction method devised in this work