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Performance Advantage (performance + advantage)
Selected AbstractsMultimedia vectorization of floating-point MIN/MAX reductionsCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 9 2006Aart J. C. Bik Abstract Finding the minimum or maximum value in an array forms an important step in a variety of applications. This paper discusses vectorization schemes that take advantage of the streaming-SIMD-extensions in commonly used floating-point MIN and MAX reductions. Performance advantages are demonstrated with experimental results. Copyright © 2006 John Wiley & Sons, Ltd. [source] Demographic vital rates determine the performance advantage of crop,wild hybrids in lettuceJOURNAL OF APPLIED ECOLOGY, Issue 6 2005DANNY A. P. HOOFTMAN Summary 1Hybridization seems possible for many crop species after pollen transfer from crops to wild relatives in the surrounding vegetation. Subsequent introgression of crop-specific traits into wild relatives could lead to invasive introgressants. This process has become a public concern following the introduction of genetically modified (GM) crops. Until now, few studies have used demographic vital rates to compare the performance of hybrids with their wild relatives. 2We created second-generation (S1 and BC1) hybrids between the non-transgenic crop Lactuca sativa and its entirely cross-fertile wild relative Lactuca serriola. Seeds of parents and hybrids were individually sown in field plots at three different locations. Next to germination and survival, we measured a range of single fitness components and morphological traits. We also compared observed phenotypes to phenotypes theoretically expected, according to different inheritance scenarios. 3Phenotypes of both hybrid classes resembled L. serriola closely, and more than theoretically expected. However, demographic vital rates, i.e. germination and survival of hybrids were much higher than in L. serriola. 4Our results indicate that hybrids between crop and wild Lactuca are phenotypically indistinguishable from the wild relative and thus will largely remain unnoticed when they occur. However, these hybrids could potentially become invasive because of substantial differences in vital rates and seeds returned per seed sown. 5Synthesis and applications. A comparative study on single fitness components, such as seed production, alone would not have revealed the performance advantage of crop,wild hybrids in Lactuca. Therefore, studying demographic vital rates of hybrids and back-crosses to test for long-term consequences of hybridization should be part of any risk assessment of GM crops. Demographic vital rates are also important for the development of predictive modelling tools that can be employed to test the individual- and population-level consequences of new-to-add traits. [source] Clinical efficacy of prostate cancer detection using power doppler imaging in American and Japanese menJOURNAL OF CLINICAL ULTRASOUND, Issue 4 2002Koji Okihara MD Abstract Purpose The aim of this study was to compare the detection rates of tumor vascular flow as measured by power Doppler imaging (PDI) in 2 populations and to determine whether PDI can reduce the number of unnecessary prostate biopsies in men with serum prostate-specific antigen (PSA) concentrations less than 10.1 ng/ml. Methods The patient populations were Japanese (group 1) and American (group 2) men with either serum PSA concentrations of 4.1,10.0 ng/ml or abnormal findings on digital rectal examination (DRE) plus PSA concentrations less than 4.1 ng/ml. We compared the overall diagnostic accuracy of DRE, gray-scale transrectal sonography (TRUS), and PDI between the 2 groups. Results In total, 275 men were studied, 154 in group 1 and 121 in group 2. Cancer was identified in 27% of men in group 1 and in 60% of group 2. Men with cancer in both groups differed significantly in age, peripheral zone volume, and mean number of positive biopsy cores. The sensitivity and specificity of PDI in group 2 were significantly inferior to those in group 1. The negative predictive value (NPV) of PDI was significantly higher for group 1 than for group 2. The NPV of PDI in group 1 was equivalent to that for the combination of DRE and TRUS, whereas the NPV for PDI in group 2 was significantly inferior to that of DRE and TRUS. Conclusions Tumor vascularity could be detected by PDI more effectively in Japanese men with cancer than in American men with cancer. We hypothesize that this difference was a result of larger cancer volumes and smaller prostates in the Japanese men. PDI did not provide any performance advantage over DRE and TRUS in avoiding unnecessary biopsies. © 2002 Wiley Periodicals, Inc. J Clin Ultrasound 30:213,221, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI: 10.1002/jcu.10054 [source] A fast, scalable method for the parallel evaluation of distance-limited pairwise particle interactionsJOURNAL OF COMPUTATIONAL CHEMISTRY, Issue 13 2005David E. Shaw Abstract Classical molecular dynamics simulations of biological macromolecules in explicitly modeled solvent typically require the evaluation of interactions between all pairs of atoms separated by no more than some distance R, with more distant interactions handled using some less expensive method. Performing such simulations for periods on the order of a millisecond is likely to require the use of massive parallelism. The extent to which such simulations can be efficiently parallelized, however, has historically been limited by the time required for interprocessor communication. This article introduces a new method for the parallel evaluation of distance-limited pairwise particle interactions that significantly reduces the amount of data transferred between processors by comparison with traditional methods. Specifically, the amount of data transferred into and out of a given processor scales as O(R3/2p,1/2), where p is the number of processors, and with constant factors that should yield a substantial performance advantage in practice. © 2005 Wiley Periodicals, Inc. J Comput Chem 26: 1318,1328, 2005 [source] Characterization of urinary metabolites of testosterone, methyltestosterone, mibolerone and boldenone in greyhound dogsJOURNAL OF VETERINARY PHARMACOLOGY & THERAPEUTICS, Issue 3 2000T. M. Williams Androgenic steroids are used in female greyhound dogs to prevent the onset of estrus; moreover, these steroids also have potent anabolic activity. As anabolic steroids increase muscle mass and aggression in animals, the excessive use of these agents in racing greyhounds gives an unfair performance advantage to treated dogs. The biotransformation of most anabolic steroids has not been determined in greyhound dogs. The objective of the present study was to identify the urinary metabolites of testosterone, methyltestosterone, mibolerone, and boldenone in greyhound dogs. These steroids were administered orally (1 mg/kg) to either male or female greyhound dogs and urine samples were collected pre-administration and at 2, 4, 8, 12, 24, 72, and 96 h post-administration. Urine extracts were analyzed by high-performance liquid chromatography/mass spectrometry (HPLC/MS) to identify major metabolites and to determine their urinary excretion profiles. Major urinary metabolites, primarily glucuronide, conjugated and free, were detected for the selected steroids. Sulfate conjugation did not appear to be a major pathway for steroid metabolism and excretion in the greyhound dog. Phase I biotransformation was also evaluated using greyhound dog liver microsomes from untreated dogs. The identification of several in vivo steroid metabolites generated in this study will be useful in detecting these steroids in urine samples submitted for drug screening. [source] Conjugated-Polymer Blends for OptoelectronicsADVANCED MATERIALS, Issue 38-39 2009Christopher R. McNeill Abstract Solution-processed polymer optoelectronic devices such as light-emitting diodes and solar cells have many advantages for large-area manufacture, and show increasing levels of performance. Here, we review recent progress in using blends of two conjugated polymers for optoelectronic devices. The blending of two or more polymers allows tuning of device performance, and for photovoltaics presents an attractive way to combine donor and acceptor materials with a morphology controlled by polymer phase separation. We discuss recent advances in imaging the microstructure of conjugated polymer blends, and we demonstrate how the blend structure leads to performance advantages in both LEDs and photovoltaic devices. [source] | ||||||||||