11,614 research outputs found
Ultraviolet hydrogen-discharge lamp
Device provides stable flux output for calibration of ultraviolet spectrum
Experimental aerodynamic heating to simulated shuttle tiles
The heat transfer to simulated shuttle thermal protection system tiles was investigated experimentally using a highly instrumented metallic thin wall tile arranged with other metal tiles in a staggered tile array. Cold-wall heating rate data for laminar and turbulent flow were obtained in the Langley 8-foot high temperature tunnel at a nominal Mach number of 7, a nominal total temperature of 3300 R, free-stream unit Reynolds number from 3.4 x 10 to the 5th power to 2.2 x 10 to the 6th power per foot, and free-stream dynamic pressure of 1.8 psia to 9.1 psia. Experimental data are presented to illustrate the effects of flow angularity and gap width on both local peak heating and overall heating loads
Development of biaxial test fixture includes cryogenic application
Test fixture has the capability of producing biaxial stress fields in test specimens to the point of failure. It determines biaxial stress by dividing the applied load by the net cross section. With modification it can evaluate materials, design concepts, and production hardware at cryogenic temperatures
Vine weeds in soybeans
"Vine weeds not only vigorously compete with crops, but they also plug up the combine and contribute to serious lodging. Once they are entangled in the soybean canopy, any attempt at cultivation strips foliage from the soybean plants. Severe infestations may cause 40 percent yield reduction. High moisture at harvest can also be a problem."--First page.Steve Livingston, L.E. Anderson, and Harold D. Kerr (Department of Agronomy, College of Agriculture)New 4/83/10
Loss of expression of ATM is associated with worse prognosis in colorectal cancer and loss of Ku70 expression is associated with CIN
Repair of double strand DNA breaks (DSBs) is pivotal in maintaining normal
cell division and disruption of this system has been shown to be a key factor in
carcinogenesis. Loss of expression of the DSB repair proteins have previously been
shown to be associated with poorer survival in colorectal cancer. We wished to
ascertain the relationship of altered expression of the DSB repair proteins γ-H2AX
(gamma-H2AX), ATM and Ku70 with biological and clinico-pathological features
of colorectal cancer. 908 tumours from the VICTOR clinical trial of stage II/III
colorectal cancer were analysed for expression of γ-H2AX, ATM and Ku70 using
immunohistochemistry. Expression levels were correlated with CIN and with diseasefree
survival, correcting for microsatellite instability, BRAF/KRAS mutation status,
Dukes stage, chemo/radiotherapy, age, gender and tumour location. Down-regulated
Ku70 expression was associated with chromosomal instability (p=0.029) in colorectal
cancer. Reduced ATM expression was an independent marker of poor disease-free
survival (HR=1.67, 95% CI 1.11-2.50, p=0.015). For Ku70, further studies are
required to investigate the potential relationship of non-homologous end joining with
chromosomal instability. Loss of ATM expression might serve as a biomarker of poor
prognosis in colorectal cancer
An experimental evaluation of a loop versus a reference design for two-channel microarrays
Motivation: Despite theoretical arguments that socalled "loop designs" of two-channel DNA microarray experiments are more efficient, biologists keep on using "reference designs". We describe two sets of microarray experiments with RNA from two different biological systems (TPA-stimulated mammalian cells and Streptomyces coelicor). In each case, both a loop and a reference design were performed using the same RNA preparations with the aim to study their relative efficiency. Results: The results of these experiments show that (1) the loop design attains a much higher precision than the reference design, (2) multiplicative spot effects are a large source of variability, and if they are not accounted for in the mathematical model, for example by taking log-ratios or including spot-effects, then the model will perform poorly. The first result is reinforced by a simulation study. Practical recommendations are given on how simple loop designs can be extended to more realistic experimental designs and how standard statistical methods allow the experimentalist to use and interpret the results from loop designs in practice
Correspondence between W. J. Kerr, A. E. Stene, F. M. Rolfs, L. H. Bailey, and Charles F. Curtiss
Correspondence concerning a position in Horticulture Botany at Utah Agricultural College
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