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census of Kuiper comets-the TAOS Project

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天文研究与技术 1999年第S1期 182-189页

作者： Wen Ping chenOther TAOS team members: c. Alcock, K. cook, S. Marshall, M. Hammergren(LLNL) T. Lee, c. Yuan, c. Y. Wen, S. K. King(ASIAA) W. S. Tsay, W. Ip, c. Lemme, J. H. Wang(NcU) T. Axelrod(ANU) I. de Pater(UcB) J.Lissauer(ames) Y. I. Byun(Yonsei

cometary nuclei, the remnant icy bodies of planet formation, located at the outer edge of the solar system, are relatively poorly studied because of their small sizes and thus faintness. Thus far more than a hundred large members (size about 100 km) of this cometary population in the Kuiper belt have been identified. Smaller bodies (10 km) are much too faint to image directly and their number so far can only be extrapolated on theoretical grounds. The Taiwan-America Occultation Survey (TAOS) will conduct a census of the number of Kuiper belt objects down to a few km size by monitoring chance stellar occultations by these cometary nuclei. We will set up an array of small (50cm), wide-field (f/1 9) telescopes, each equipped with a 2K squared ccD camera, along a 7 km baseline in central Taiwan at an elevation above ～ 3000 m. The robot telescopes will operate in a coincidence mode, so the sequence and timing of any candidate occultation event can be recorded and distinguished against a false detection. The Lawrence Livermore National Laboratory, the National central University, and the Academia Sinica, will each contribute one telescope system. Researchers from an international variety of institutes are also participating in the project. Our experiment provides the only means to study the cometary population in the small-sized end of the distrbution. A great number of scientific byproducts, notably variable stars, will also derive from the huge TAOS database, some 10, 000 giga-bytes worth of photometrical measuremements per year.

关键词： census of Kuiper comets-the TAOS Project TAOS

EcRIS charge Breeding at ISAc

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chinese Physics c 2007年第S1期31卷 211-215页

作者： F.ames R.Baartman P.Bricault K.Jayamanna M.McDonald M.Olivo P.Schmor D.H.L.Yuan T.Lamy TRIUMF 4004 Wesbrook MallVancouverBCV6t 2A3Canada LPSc UJF-IN2P3-CNRS53 Av.Des Martyrs38026 GrenobleFrance

An EcR ion source for charge breeding of radioactive ions from the ISAc facility at TRIUMF has been set up at a test *** has been operated with different ion sources for the injection of singly charged ions and the efficiency,breeding time and emittance have been determined for several elements.A maximum efficiency of more than 6% for the breeding of Kr^(12+) has been achieved so *** the charge exchange of Rb and cs ions in the range of 10+ to 23+ with residual gas molecules in the transport beam lines has been *** absolute values for the cross sections at 10—15 q keV agree with predictions extrapolated from lower charge states but the strong dependence on the ionization energy of the gas molecules could not be verified.

关键词： EcRIS charge breeding radioactive ions charge exchange

characteristics of lipids and their feeding value in swine diets

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Journal of Animal Science and Biotechnology 2016年第3期7卷 249-271页

作者： Brian J.Kerr Trey A.Kellner gerald c.Shurson USDA-ARS-National Laboratory for Agriculture and the Environment AmesIA 50011USA Department of Animal Science Iowa State UniversityAmesIA 50011USA Department of Animal Science University of MinnesotaSt.PaulMN 55108USA

In livestock diets, energy is one of the most expensive nutritional components of feed formulation. Because lipids are a concentrated energy source, inclusion of lipids are known to affect growth rate and feed efficiency, but are also known to affect diet palatability, feed dustiness, and pellet quality. In reviewing the literature, the majority of research studies conducted on the subject of lipids have focused mainly on the effects of feeding presumably high quality lipids on growth performance, digestion, and metabolism in young animals. There is, however, the wide array of composition and quality differences among lipid sources available to the animal industry making it essential to understand differences in lipid composition and quality factors affecting their digestion and metabolism more fully. In addition there is often confusion in lipid nomenclature, measuring lipid content and composition, and evaluating quality factors necessary to understand the true feeding value to animals. Lastly, advances in understanding lipid digestion, post-absorption metabolism, and physiological processes（e.g., cell division and differentiation, immune function and inflammation）; and in metabolic oxidative stress in the animal and lipid peroxidation, necessitates a more compressive assessment of factors affecting the value of lipid supplementation to livestock diets. The following review provides insight into lipid classification, digestion and absorption, lipid peroxidation indices, lipid quality and nutritional value, and antioxidants in growing pigs.

关键词： Digestion Energy Lipids Peroxidation Pigs

A High-Throughput Phenotyping Pipeline for Image Processing and Functional growth curve Analysis

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Plant Phenomics 2020年第1期2卷 188-195页

作者： Ronghao Wang Yumou Qiu Yuzhen Zhou Zhikai Liang James c.Schnable Department of Statistics University of Nebraska-LincolnLincoln 68503USA Department of Statistics Iowa State UniversityAmes 50011USA Department of Plant and Microbial Biology University of MinnesotaSaint PaulMN 55108USA center for Plant Science Innovation Department of Agronomy and HorticultureUniversity of Nebraska-LincolnLincoln 68503USA

High-throughput phenotyping system has become more and more popular in plant science *** data analysis for such a system typically involves two steps:plant feature extraction through image processing and statistical analysis for the extracted *** current approach is to perform those two steps on different *** develop the package“implant”in R for both robust feature extraction and functional data *** image processing,the“implant”package provides methods including thresholding,hidden Markov random field model,and morphological *** statistical analysis,this package can produce nonparametric curve fitting with its confidence region for plant growth.A functional ANOVA model to test for the treatment and genotype effects on the plant growth dynamics is also provided.

关键词： steps image operations

genetic parameters of drinking and feeding traits of wean-to-finish pigs under a polymicrobial natural disease challenge

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Journal of Animal Science and Biotechnology 2022年第1期13卷 17-35页

作者： Jian cheng Austin M.Putz John c.S.Harding Michael K.Dyck Frederic Fortin graham S.Plastow Pig gen canada Jack c.M.Dekkers Department of Animal Science Iowa State UniversityAmesIA 50011USA Hendrix genetics Swine Business UnitBoxmeerThe Netherlands 5831CK Department of Large Animal clinical Science University of SaskatchewanSaskatoonSK S7N 5A2Canada Department of Agriculture Food and Nutritional ScienceUniversity of AlbertaEdmontonAB T6G 2R3Canada centre de Developpement du Porc du Quebec Inc. Quebec City G1V 4M6Canada Piggen canada Research consortium GuelphOntario N1H4G8Canada

Bac.g.ound:The pork industry faces unprecedented challenges from disease,which increases cost of production and use of antibiotics,and reduces production efficiency,carcass quality,and animal *** solution is to improve the overall resilience of pigs to a broad array of common diseases through genetic *** changes in feeding and drinking are usually the very first clinical signs when animals are exposed to stressors such as *** in feeding and drinking behaviors in diseased pigs may reflect the way they cope with the challenge and,thus,could be used as indicator traits to select for disease *** objectives of this study were to estimate genetic parameters of feeding and drinking traits for wean-to-finish pigs in a natural polymicrobial disease challenge model,to estimate genetic correlations of feeding and drinking traits with growth rate and clinical disease traits,and to develop indicator traits to select for disease ***:In general,drinking traits had moderate to high estimates of heritability,especially average daily water dispensed,duration,and number of visits(0.44 to 0.58).Similar estimates were observed for corresponding feeding traits(0.35 to 0.51).Most genetic correlation estimates among drinking traits were moderate to high(0.30 to 0.92)and higher than among feeding traits(0 to 0.11).compared to other drinking traits,water intake duration and number of visits had relatively stronger negative genetic correlation estimates with treatment rate and mortality,especially across the challenge nursery and finisher(−0.39 and−0.45 for treatment rate;−0.20 and−0.19 for mortality).conclusion:Most of the recorded drinking and feeding traits under a severe disease challenge had moderate to high estimates of heritability,especially for feed or water intake duration and number of *** and genetic correlations among the recorded feeding traits under disease were generally low but drinking traits show

关键词： Disease resilience Feeding and drinking behavior genetic parameters Pigs

comparative Study of Three High Order Schemes for LES of Temporally Evolving Mixing Layers

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communications in computational Physics 2012年第10期12卷 1603-1622页

作者： Helen c.Yee Bjorn Sjögreen Abdellah Hadjadj NASA-ames Research center Moffett FieldCA94035USA Lawrence Livermore National Laboratory LivermoreCA94551USA cORIA UMR 6614&INSA de Rouen 76800 St-Etienne du RouvrayFrance

Three high order shock-capturing schemes are compared for large eddy simulations(LES)of temporally evolving mixing layers for different convective Mach numbers ranging from the quasi-incompressible regime to highly compressible supersonic *** considered high order schemes are fifth-order WENO(WENO5),seventh-order WENO(WENO7)and the associated eighth-order central spatial base scheme with the dissipative portion of WENO7 as a nonlinear post-processing filter step(WENO7fi).This high order nonlinear filter method of Yee&Sjogreen is designed for accurate and efficient simulations of shock-free compressible turbulence,turbulence with shocklets and turbulence with strong shocks with minimum tuning of scheme *** LES results by WENO7fi using the same scheme parameter agree well with experimental results compiled by Barone et al.,and published direct numerical simulations(DNS)work of Rogers&Moser and Pantano&Sarkar,whereas results by WENO5 andWENO7 compare poorly with experimental data and DNS computations.

关键词： High order numerical methods numerical methods for turbulencewith shocks DNS LES mixing layer

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In Memoriam:*** ***

International Soil and Water conservation Research 2021年第4期9卷 485-489页

作者： Dennis c.Flanagan Richard M.cruse James L.Baker Paige chyu USDA-Agricultural Research Service National Soil Erosion Research LaboratoryWest LafayetteINUSA Department of Agronomy Iowa State UniversityAmesIAUSA Department of Agricultural&Biosystems Engineering Iowa State UniversityAmesIAUSA International Research and Training center on Erosion and Sedimentation BeijingChina

The soil erosion research and soil and water conservation global community lost a treasured member on November 20,2020,when *** Matthew Laflen(Fig.1)*** one with a friendly welcoming smile,John had hundreds of friends,both personally and professionally throughout the *** article includes many of his professional and scientific contributions,and impacts from his research and outreach activities.

关键词： soil hundreds professional

Oxidation of As(Ⅲ) by potassium permanganate

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Journal of Environmental Sciences 2007年第7期19卷 783-786页

作者： LI Na FAN Maohong Van Leeuwen Johannes Saha Basudeb YANg Hongqun HUANg c. P. Department of civil Construction and Environmental Engineering Center for Sustainable Environmental Technology Iowa State University Ames Iowa 50011 USA. center for Sustainable Environmental Technology Iowa State University Ames Iowa 50011 USA Department of chemistry Iowa State University Ames Iowa 50011 USA Department of chemical and Materials Engineering University of Alberta Edmonton Alberta T6G 2G6 Canada Department of civil and Environmental Engineering University of Delaware Newark DE 19716 USA

The oxidation of As（Ⅲ） with potassium permanganate was studied under conditions including pH, initial As（Ⅲ） concentration and dosage of Mn（Ⅶ）. The results have shown that potassium permanganate was an effective agent for oxidation of As（Ⅲ） in a wide pH range. The pH value of tested water was not a significant factor affecting the oxidation of As（Ⅲ） by Mn（Ⅲ）. Although theoretical redox analyses suggest that Mn（Ⅶ） should have better performance in oxidization of As（Ⅲ） within lower pH ranges, the experimental results show that the oxidation efficiencies of As（Ⅲ） under basic and acidic conditions were similar, which may be due to the adsorption of As（Ⅲ） on the Mn（OH）2 and MnO2 resulting from the oxidation of As（Ⅲ）.

关键词： arsenite arsenate oxidation potassium permanganate

Effects of low-oxygen conditions on embryo growth in the painted turtle,chrysemys picta

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Integrative Zoology 2017年第2期12卷 148-156页

作者： gerardo A.cORDERO Matthew L.KARNATZ Jon c.SVENDSEN Eric J.gANgLOFF Department of Ecology Evolutionand Organismal BiologyIowa State UniversityAmesIowaUSA Technical University of Denmark National Institute of Aquatic ResourcesFreshwater FisheriesSilkeborgDenmark Interdisciplinary centre of Marine and Environmental Research University of PortoPortoPortugal

Low-oxygen conditions(hypoxia;<21%O_(2))are considered unfavorable for growth;yet,embryos of many vertebrate taxa develop successfully in hypoxic subterranean *** enhanced tolerance to hypoxia has been demonstrated in... 详细信息

Low-oxygen conditions(hypoxia;considered unfavorable for growth;yet,embryos of many vertebrate taxa develop successfully in hypoxic subterranean *** enhanced tolerance to hypoxia has been demonstrated in adult reptiles,such as in the painted turtle(chrysemys picta),its effects on sensitive embryo life stages warrant *** tested the hypothesis that short-term hypoxia negatively affects growth during day 40 of development in ***,when O_(2) demands are highest in embryos.A brief,but severe,hypoxic event(5%O_(2) for 0.5 h)moderately affected embryo growth,causing a 13%reduction in mass(relative to a normoxic control).The same condition had no effect during day 27;instead,a nearly anoxic event(1%O_(2) for 72 h)caused a 5%mass *** embryos survived the egg incubation *** study supports the assumption that reptilian embryos are resilient to intermittently low O_(2) in subterranean *** work is needed to ascertain responses to suboptimal O_(2) levels while undergoing dynamic changes in developmental physiology.

关键词： embryo metabolism embryo respiration growth rate nest environment oxygen consumption rate