4,504 research outputs found
PO-0936: Comparative study between 3D-CRT and IMRT in defintive treatment of cervical cancer
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
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
Influence of analysis and design models on minimum weight design
The results of numerical experiments designed to illustrate how the minimum weight design, accuracy, and cost can be influenced by: (1) refinement of the finite element analysis model and associated load path problems, and (2) refinement of the design variable linking model are examined. The numerical experiments range from simple structures where the modelling decisions are relatively obvious and less costly to the more complex structures where such decisions are less obvious and more costly. All numerical experiments used employ the dual formulation in ACCESS-3 computer program. Guidelines are suggested for creating analysis and design models that predict a minimum weight structure with greater accuracy and less cost. These guidelines can be useful in an interactive optimization environment and in the design of heuristic rules for the development of knowledge-based expert optimization systems
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
Advanced gearbox technology
An advanced 13,000 HP, counterrotating (CR) gearbox was designed and successfully tested to provide a technology base for future designs of geared propfan propulsion systems for both commercial and military aircraft. The advanced technology CR gearbox was designed for high efficiency, low weight, long life, and improved maintainability. The differential planetary CR gearbox features double helical gears, double row cylindrical roller bearings integral with planet gears, tapered roller prop support bearings, and a flexible ring gear and diaphragm to provide load sharing. A new Allison propfan back-to-back gearbox test facility was constructed. Extensive rotating and stationary instrumentation was used to measure temperature, strain, vibration, deflection and efficiency under representative flight operating conditions. The tests verified smooth, efficient gearbox operation. The highly-instrumented advanced CR gearbox was successfully tested to design speed and power (13,000 HP), and to a 115 percent overspeed condition. Measured CR gearbox efficiency was 99.3 percent at the design point based on heat loss to the oil. Tests demonstrated low vibration characteristics of double helical gearing, proper gear tooth load sharing, low stress levels, and the high load capacity of the prop tapered roller bearings. Applied external prop loads did not significantly affect gearbox temperature, vibration, or stress levels. Gearbox hardware was in excellent condition after the tests with no indication of distress
Influence of peptidylarginine deiminase type 4 genotype and shared epitope on clinical characteristics and autoantibody profile of rheumatoid arthritis.
Background: Recent evidence suggests that distinction
of subsets of rheumatoid arthritis (RA) depending on anticyclic
citrullinated peptide antibody (anti-CCP) status may
be helpful in distinguishing distinct aetiopathologies and in
predicting the course of disease. HLA-DRB1 shared
epitope (SE) and peptidylarginine deiminase type 4
(PADI4) genotype, both of which have been implicated in
anti-CCP generation, are assumed to be associated with
RA.
Objectives: To elucidate whether PADI4 affects the
clinical characteristics of RA, and whether it would
modulate the effect of anti-CCPs on clinical course. The
combined effect of SE and PADI4 on autoantibody profile
was also analysed.
Methods: 373 patients with RA were studied. SE,
padi4_94C.T, rheumatoid factor, anti-CCPs and antinuclear
antibodies (ANAs) were determined. Disease
severity was characterised by cumulative therapy
intensity classified into ordinal categories (CTI-1 to CTI-3)
and by Steinbrocker score.
Results: CTI was significantly associated with disease
duration, erosive disease, disease activity score (DAS) 28
and anti-CCPs. The association of anti-CCPs with CTI was
considerably influenced by padi4_94C.T genotype (C/C:
ORadj=0.93, padj=0.92; C/T: ORadj=2.92,
padj=0.093; T/T: ORadj=15.3, padj=0.002). Carriage of
padi4_94T exhibited a significant trend towards higher
Steinbrocker scores in univariate and multivariate
analyses. An association of padi4_94C.T with ANAs
was observed, with noteworthy differences depending on
SE status (SE2: ORadj=6.20, padj,0.04; SE+:
ORadj=0.36, padj=0.02) and significant heterogeneity
between the two SE strata (p=0.006).
Conclusions: PADI4 genotype in combination with anti-
CCPs and SE modulates clinical and serological characteristics
of RA
The Performance of the Robo-AO Laser Guide Star Adaptive Optics System at the Kitt Peak 2.1-m Telescope
Robo-AO is an autonomous laser guide star adaptive optics system recently
commissioned at the Kitt Peak 2.1-m telescope. Now operating every clear night,
Robo-AO at the 2.1-m telescope is the first dedicated adaptive optics
observatory. This paper presents the imaging performance of the adaptive optics
system in its first eighteen months of operations. For a median seeing value of
, the average Strehl ratio is 4\% in the band
and 29\% in the J band. After post-processing, the contrast ratio under
sub-arcsecond seeing for a primary star is five and
seven magnitudes at radial offsets of and
, respectively. The data processing and archiving pipelines
run automatically at the end of each night. The first stage of the processing
pipeline shifts and adds the data using techniques alternately optimized for
stars with high and low SNRs. The second "high contrast" stage of the pipeline
is eponymously well suited to finding faint stellar companions.Comment: 12 pages, 16 figures, to be submitted to PAS
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