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131.
Gary Demos 《The Visual computer》2005,21(12):961-978
Gary Demos discovered computer graphics while hearing a computer-generated film presentation at CalTech in 1970 by John Whitney
Sr. Gary then began working under the direction of Ivan Sutherland in Utah to develop early computer graphics hardware and
software. In 1974 Gary and John Whitney Jr. started the “Motion Picture Project” at Information International to produce computer
generated simulated scenes for movies (Futureworld, Looker, and Tron) and commercials. These early computer-generated visuals
were quite challenging given the level of software and hardware technology available in the 1970’s. In 1981 Gary and John
left Information International to form Digital Productions, where they produced effects for the movies Last Starfighter and
“2010”, which were both released in 1984. Digital Productions used the Cray XMP computer, together with the Digital Film Printer
that they had developed at Information International. Following a hostile takeover by Omibus of Digital Productions in 1986,
Whitney/Demos Productions was formed, using a Thinking Machine parallel computer. This paper describes the technical challenges
and achievements of this early visual computing. 相似文献
132.
Kraut Robert; Olson Judith; Banaji Mahzarin; Bruckman Amy; Cohen Jeffrey; Couper Mick 《Canadian Metallurgical Quarterly》2004,59(2):105
As the Internet has changed communication, commerce, and the distribution of information, so too it is changing psychological research. Psychologists can observe new or rare phenomena online and can do research on traditional psychological topics more efficiently, enabling them to expand the scale and scope of their research. Yet these opportunities entail risk both to research quality and to human subjects. Internet research is inherently no more risky than traditional observational, survey, or experimental methods. Yet the risks and safeguards against them will differ from those characterizing traditional research and will themselves change over time. This article describes some benefits and challenges of conducting psychological research via the Internet and offers recommendations to both researchers and institutional review boards for dealing with them. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
133.
Gary T. Anderson Youlong Yang Gang Cheng 《Journal of Intelligent and Robotic Systems》2009,54(5):755-767
This paper proposes a unique oscillator-based robot controller with learning abilities to effectively guide a team of robots
operating in uncertain environments. To verify this, we designed four separate controllers and compared their performance
in a series of tests in several different environments. The experiments used a team of three robots to explore arenas with
variable lighting and different obstacle patterns, with a goal of having the team as a whole absorb as much light as possible.
The four controllers were: a reactive controller, an oscillator with fixed parameters, an oscillator whose parameters changed
based on the pattern of sensor information received, and an oscillator-based controller that used reinforcement learning.
Experiments confirmed that the proposed method outperforms the others in all environments tested.
This material is based upon work supported in part by the U.S. Army Research Office under grant/contract number DAAG55-98-1-0011. 相似文献
134.
Mithun Santra Yu-Chi Liu Vishal Jhanji Gary Hin-Fai Yam 《International journal of molecular sciences》2022,23(14)
A transparent cornea is paramount for vision. Corneal opacity is one of the leading causes of blindness. Although conventional corneal transplantation has been successful in recovering patients’ vision, the outcomes are challenged by a global lack of donor tissue availability. Bioengineered corneal tissues are gaining momentum as a new source for corneal wound healing and scar management. Extracellular matrix (ECM)-scaffold-based engineering offers a new perspective on corneal regenerative medicine. Ultrathin stromal laminar tissues obtained from lenticule-based refractive correction procedures, such as SMall Incision Lenticule Extraction (SMILE), are an accessible and novel source of collagen-rich ECM scaffolds with high mechanical strength, biocompatibility, and transparency. After customization (including decellularization), these lenticules can serve as an acellular scaffold niche to repopulate cells, including stromal keratocytes and stem cells, with functional phenotypes. The intrastromal transplantation of these cell/tissue composites can regenerate native-like corneal stromal tissue and restore corneal transparency. This review highlights the current status of ECM-scaffold-based engineering with cells, along with the development of drug and growth factor delivery systems, and elucidates the potential uses of stromal lenticule scaffolds in regenerative therapeutics. 相似文献
135.
Reactivity characteristics of nanoscale zerovalent iron--silica composites for trichloroethylene remediation 总被引:1,自引:0,他引:1
Zheng T Zhan J He J Day C Lu Y McPherson GL Piringer G John VT 《Environmental science & technology》2008,42(12):4494-4499
Spherical silica particles containing nanoscale zerovalent iron were synthesized through an aerosol-assisted process. These particles are effective for groundwater remediation, with the environmentally benign silica particles serving as effective carriers for nanoiron transport. Incorporation of iron into porous sub-micrometer silica particles protects ferromagnetic iron nanoparticles from aggregation and may increase their subsurface mobility. Additionally, the presence of surface silanol groups on silica particles allows control of surface properties via silanol modification using organic functional groups. Aerosolized silica particles with functional alkyl moieties, such as ethyl groups on the surface, clearly adsorb solubilized trichloroethylene (TCE) in water. These materials may therefore act as adsorbents which have coupled reactivity characteristics. The nanoscale iron/silica composite particles with controlled surface properties have the potential to be efficiently applied for in situ source depletion and in the design of permeable reactive barriers. 相似文献
136.
Several recent foodborne disease outbreaks associated with leafy green vegetables, including spinach, have been reported. X-ray is a non-thermal technology that has shown promise for reducing pathogenic and spoilage bacteria on spinach leaves. Inactivation of inoculated Escherichia coli O157:H7, Listeria monocytogenes, Salmonella enterica and Shigella flexneri on spinach leaves using X-ray at different doses (0.1, 0.2, 0.3, 0.5, 0.75, 1.0, 1.5 and 2.0 kGy) was studied. The effect of X-ray on color quality and microflora counts (mesophilic counts, psychrotrophic counts and yeast and mold counts) of untreated and treated spinach was also determined. A mixture of three strains of each tested organism was spot inoculated (100 μl) onto the surface of spinach leaves (approximately 8–9 log ml−1), separately, and air-dried, followed by treatment with X-ray at 22 °C and 55–60% relative humidity. Surviving bacterial populations on spinach leaves were evaluated using a nonselective medium (tryptic soy agar) with a selective medium overlay for each bacteria; E. coli O157:H7 (CT-SMAC agar), L. monocytogenes (MOA), and S. enterica and S. flexneri (XLD). More than a 5 log CFU reduction/leaf was achieved with 2.0 kGy X-ray for all tested pathogens. Furthermore, treatment with X-ray significantly reduced the initial inherent microflora on spinach leaves and inherent levels were significantly (p < 0.05) lower than the control sample throughout refrigerated storage for 30 days. Treatment with X-ray did not significantly affect the color of spinach leaves, even when the maximum dose (2.0 kGy) was used. 相似文献
137.
Estrogen content of dairy and swine wastes 总被引:3,自引:0,他引:3
Raman DR Williams EL Layton AC Burns RT Easter JP Daugherty AS Mullen MD Sayler GS 《Environmental science & technology》2004,38(13):3567-3573
Naturally occurring estrogens in animal wastes may cause negative environmental impacts, yet their abundance in animal waste treatment and storage structures is poorly documented. To better quantify estrogen concentrations in animal wastes, multiple waste samples were collected from treatment and storage structures at dairy and swine facilities and analyzed for concentrations of 17beta-estradiol (E2), estrone (E1), and 17alpha-estradiol by gas chromatography-mass spectroscopy and by enzyme linked immunosorbent assay (E2 only). Mass ratios of each estrogen to the macronutrients nitrogen, phosphorus, and potassium were also determined. Because manure application rates are typically macronutrient-based, estrogen to macronutrient ratios are proportional to areal mass application rates of estrogen to fields. Swine farrowing waste (from farrowing sows and piglets) had the highest ratios of E2 to macronutrients. Mean ratios in swine farrowing waste were roughly twice those in swine finishing waste (from growing male and nonpregnant female animals) and more than four times higher than those in dairy waste (from lactating cows in various stages of their reproductive cycles); these differences were statistically significant (alpha = 0.05). Estrone followed a similar trend. In contrast, ratios of 17alpha-estradiol to macronutrients were highest in dairy operations. These results can be used to better predict estrogen loading rates on fields receiving swine and dairy wastes. 相似文献
138.
Michael S. Koch John M. DeSesso Amy Lavin Williams Suzanne Michalek Bruce Hammond 《Critical reviews in food science and nutrition》2016,56(3):512-526
To determine the reliability of food safety studies carried out in rodents with genetically modified (GM) crops, a Food Safety Study Reliability Tool (FSSRTool) was adapted from the European Centre for the Validation of Alternative Methods’ (ECVAM) ToxRTool. Reliability was defined as the inherent quality of the study with regard to use of standardized testing methodology, full documentation of experimental procedures and results, and the plausibility of the findings. Codex guidelines for GM crop safety evaluations indicate toxicology studies are not needed when comparability of the GM crop to its conventional counterpart has been demonstrated. This guidance notwithstanding, animal feeding studies have routinely been conducted with GM crops, but their conclusions on safety are not always consistent. To accurately evaluate potential risks from GM crops, risk assessors need clearly interpretable results from reliable studies. The development of the FSSRTool, which provides the user with a means of assessing the reliability of a toxicology study to inform risk assessment, is discussed. Its application to the body of literature on GM crop food safety studies demonstrates that reliable studies report no toxicologically relevant differences between rodents fed GM crops or their non-GM comparators. 相似文献
139.
Qingguo Tian Robeena M. Aziz Gary D. Stoner Teven J. Schwartz 《Journal of food science》2005,70(1):C43-C47
ABSTRACT: The capabilities of mass spectrometry for microscale determination of anthocyanins were investigated using high-performance liquid chromatography electrospray ionization mass spectrometry (LC-ESI/ MS) and tandem mass spectrometry (MS-MS). Four anthocyanins [cyanidin 3-glucoside, cyanidin 3-sambubioside, cyanidin 3–(2G −xylosylrutinoside) and cyanidin 3-rutinoside] were characterized in black raspberry samples by LC-ESI/MS-MS using both positive and negative ion analyses. Quantification of anthocyanins was conducted using ESI/MS-MS with selected reaction monitoring (SRM). Linear responses of several anthocyanins were determined during MS-MS analyses. Detection limits as low as 1 femtomol for most anthocyanins were obtained during ESI/MS-MS. Compared with other quantitative procedures such as high-performance liquid chromatography (HPLC) and ultraviolet/visible spectrophotometry, the current method provides an improved sensitive, specific technique for direct determination of intact anthocyanins. The developed methodology was successfully applied to analysis of trace levels of anthocyanins in human plasma and epithelial cells. 相似文献
140.
Integration of Emerging Biomedical Technologies in Meat Processing to Improve Meat Safety and Quality 下载免费PDF全文
Joshua T. Ravensdale Ranil Coorey Gary A. Dykes 《Comprehensive Reviews in Food Science and Food Safety》2018,17(3):615-632
Modern‐day processing of meat products involves a series of complex procedures designed to ensure the quality and safety of the meat for consumers. As the size of abattoirs increases, the logistical problems associated with large‐capacity animal processing can affect the sanitation of the facility and the meat products, potentially increasing transmission of infectious diseases. Additionally, spoilage of food from improper processing and storage increases the global economic and ecological burden of meat production. Advances in biomedical and materials science have allowed for the development of innovative new antibacterial technologies that have broad applications in the medical industry. Additionally, new approaches in tissue engineering and nondestructive cooling of biological specimens could significantly improve organ transplantation and tissue grafting. These same strategies may be even more effective in the preservation and protection of meat as animal carcasses are easier to manipulate and do not have the same stringent requirements of care as living patients. This review presents potential applications of emerging biomedical technologies in the food industry to improve meat safety and quality. Future research directions investigating these new technologies and their usefulness in the meat processing chain along with regulatory, logistical, and consumer perception issues will also be discussed. 相似文献