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National Swine Genetic Improvement: An overview of essential program components and organizational structure needed for success

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华南农业大学学报 2005年第S1期26卷 20-27页

作者： John MABRY Iowa Pork Industry center Iowa State University ames IA 50014 USA

The swine industry in China is a thriving and evolving industry that has shown phenomenal growth over the past 10 years. To insure long term success and viability in a worldwide competitive industry such as pork, there is need for a National Swine Genetic Improvement Program. This program needs to draw on expertise and technology from across the world for its development, but it should be based on the structure of the pig industry in China and be led by Chinese scientists, administrators and producers. National Genetic Improvement requires more than just technology. A successful program of national genetic improvement will require cooperation from the industry and the government. The support for the university system is essential for the success of the pig industry. The university system has a vital role on education (of students, faculty, producers and consumers) as well as research and technology transfer. The government could also have a role in supporting the central test stations and AI stations across the country. An accurate and comprehensive pedigree maintenance system is essential to genetic improvement. And it will be vitally important to be active in the importation of new genetics to sample other populations.

关键词： swine National Genetic Improvement Program organizational structure

Design of refractory multi-principal-element alloys for high-temperature applications

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npj Computational Materials 2023年第1期9卷 884-893页

作者： Gaoyuan Ouyang Prashant Singh Ranran Su Duane D.Johnson Matthew J.Kramer John H.Perepezko Oleg N.Senkov Daniel Miracle Jun Cui Division of Materials Science and Engineering Ames LaboratoryAmesIA 50011USA Department of Materials Science and Engineering University of Wisconsin-MadisonMadisonWI 53706USA Department of Materials Science and Engineering Iowa State UniversityAmesIA 50011USA Air Force research Laboratory Materials and Manufacturing DirectorateWright-Patterson Air Force BaseDaytonOH 45433USA

Refractory multi-principal-element alloys(RMPEAs)exhibit high specific strength at elevated temperatures(T).However,current RMPEAs lack a balance of room-temperature(RT)ductility,high-T strength,and high-T creep *** density-functional theory methods,we scanned composition space using four criteria:(1)formation energies for operational stability:-150250 GPa;(3)inverse Pugh ratio for ductility:G/B2500°*** rapid bulk alloy synthesis and characterization,we validated theory and down-selected promising alloy compositions and discovered Mo72.3W12.8Ta10.0Ti2.5Zr2.5 having well-balanced RT and high-T mechanical *** alloy has comparable high-T compressive strength to well-known MoNbTaW but is more ductile and more creep *** is also superior to a commercial Mo-based refractory alloy and a nickel-based superalloy(Haynes-282)with improved high-T tensile strength and creep resistance.

关键词： creep alloy alloys

Ammonia Removal from Rodent Habitat Operations in Space Using Phosphoric Acid Treated Activated Carbon

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American Journal of Analytical Chemistry 2013年第12期4卷 776-780页

作者： Zhe Lu Jacob A. Hines Daniel J. Rozewicz Michael L. Hines Lockheed Martin Space OPNS Moffett Field USA nasa ames research center Moffett Field USA University of California Santa Barbara USA

To accommodate long duration biology research with rodent habitats on the International Space Station while providing a healthy living and working environment for crewmembers, nasa ames research center developed a new exhaust filter for odor control for the Animal Enclosure Module (AEM), which houses mice and rats. The new exhaust filter uses activated carbon pellets as adsorbents, with phosphoric acid (H3PO4) impregnated on the surface. The deodorization performance of the new exhaust filters for AEM units housed with mice was evaluated. The ammonia breakthrough time of the exhaust filters was also investigated. The results indicated that H3PO4 treated activated carbon exhibited a high ammonia adsorption capacity of more than 90%. Furthermore, the new exhaust filter can effectively control the odor from the AEM units for a 45-day (minimum) flight mission with a given animal biomass.

关键词： Activated Carbon Impregnation Adsorption Ammonia International Space Station

凝结相中功能性碳材料和碳纳米复合物催化转化生物质制备可再生化学品(英文)

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催化学报 2014年第6期35卷 842-855页

作者： John Matthiesen Thomas Hoff Chi Liu Charles Pueschel Radhika Rao Jean-Philippe Tessonnier Department of Chemical & Biological Engineering Iowa State University Ames IA 50011 USA US Department of Energy ames Laboratory Ames IA 50011 USA NSF-ERC center for Biorenewable Chemicals (CBiRC) Ames IA 50011 USA

The production of chemicals from lignocellulosic biomass provides opportunities to synthesize chemicals with new functionalities and grow a more sustainable chemical industry. However, new challenges emerge as research transitions from petrochemistry to biorenewable chemistry. Compared to petrochemisty, the selective conversion of biomass-derived carbohydrates requires most catalytic reactions to take place at low temperatures (< 300 °C) and in the condensed phase to prevent reactants and products from degrading. The stability of heterogeneous catalysts in liquid water above the normal boiling point represents one of the major challenges to overcome. Herein, we review some of the latest advances in the field with an emphasis on the role of carbon materials and carbon nanohybrids in addressing this challenge.

关键词：生物质转化碳水化合物纳米复合物催化反应化学物可再生凝聚相功能化学品

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纤维陶瓷隔热系统

宇航材料工艺 1990年第5期20卷 30-34页

作者： Howard E.Goldstein 谭剑波 nasa ames研究中心

本文介绍nasa阿姆斯(ames)研究中心从70年代开始所研制的热防护系统的性能和制造方法。这些材料能很好地满足航天飞机的多次飞行及宇宙恶劣环境的要求。

关键词：纤维陶瓷复合材料隔热系统航天

Terrestrial Ecosystem Carbon Fluxes Predicted from MODIS Satellite Data and Large-Scale Disturbance Modeling

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International Journal of Geosciences 2012年第3期3卷 469-479页

作者： Christopher Potter Steven Klooster Vanessa Genovese Cyrus Hiatt Shyam Boriah Vipin Kumar Varun Mithal Ashish Garg California State University Monterey Bay Seaside CA USA nasa ames research center Moffett Field CA USA University of Minnesota Minneapolis MN USA

The CASA (Carnegie-ames-Stanford) ecosystem model based on satellite greenness observations has been used to estimate monthly carbon fluxes in terrestrial ecosystems from 2000 to 2009. The CASA model was driven by nasa Moderate Resolution Imaging Spectroradiometer (MODIS) vegetation cover properties and large-scale (1-km resolution) disturbance events detected in biweekly time series data. This modeling framework has been implemented to estimate historical as well as current monthly patterns in plant carbon fixation, living biomass increments, and long-term decay of woody (slash) pools before, during, and after land cover disturbance events. Results showed that CASA model predictions closely followed the seasonal timing of Ameriflux tower measurements. At a global level, predicting net ecosystem production (NEP) flux for atmospheric CO2 from 2000 through 2005 showed a roughly balanced terrestrial biosphere carbon cycle. Beginning in 2006, global NEP fluxes became increasingly imbalanced, starting from -0.9 Pg C yr-1 to the largest negative (total net terrestrial source) flux of -2.2 Pg C yr-1 in 2009. In addition, the global sum of CO2 emissions from forest disturbance and biomass burning for 2009 was predicted at 0.51 Pg C yr-1. These results demonstrate the potential to monitor and validate terrestrial carbon fluxes using nasa satellite data as inputs to ecosystem models.

关键词： Carbon Flux Deforestation MODIS Ecosystem Production

Evaluation of fall armyworm resistance in maize germplasm lines using visual leaf injury rating and predator survey

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Insect Science 2014年第5期21卷 541-555页

作者： Xinzhi Ni Wenwei Xu Michael H. Blanco W. Paul Williams USDA-ARS Crop Genetics and Breeding Research Unit University of Georgia-Tifton Tifton GA 31793 Agricultural research &Extension center Texas A&M University Lubbock TX 79403 USDA-ARS Plant Introduction Research Unit Iowa State UniversityAmes IA 50011 Corn Host Plant Resistance research Unit USDA-ARS Mississippi State MS 39762 USA

After examining ear-colonizing pest resistance, 20 maize lines from the USDA- ARS Germplasm Enhancement of Maize （GEM） Program were evaluated for whorl-feeding fall armyworm （FAW）（Spodopterafrugiperda） resistance using 4 maize inbred lines as the resistant and susceptible controls. Both FAW injury ratings at 7- and 14-d after infestation, and predator abundance and diversity at whorl stage （V6-V8） were recorded in 2009 and 2010. The survey of the diversity and abundance of predators in each experimental plot were conducted 7 d after the FAW infestation. Of the 20 germplasm lines examined, 3 of them （i.e., entries 9, 15, and 19 that were derived from tropical maize germplasm lines were originated from Uruguay, Cuba, and Thailand, respectively） were identified as the best FAW-resistant germplasm lines using the leaf injury ratings and predator survey data. In addition, the abundance and diversity of the predators were greater in 2010 than in 2009, which might have caused the low level of the FAW injury ratings on all lines examined in 2010. The 2-year data showed that the FAW injury ratings were negatively correlated to the predator abundance and diversity, which is also influence by genotype × environment interactions. The findings suggested that tropical germplasm is an important source of native resistance to the FAW and the corn earworm. At the same time, the maize genotype x environment interaction （e.g., predator attractiveness, and varying weather conditions） should be included in the multiple-year evaluations of insect and disease resistance of maize germplasm lines under field conditions.

关键词： field screening genotype × environment interactions multiple insect resistance predator abundance and diversity whorl-feeding

Comparison of In-Use Operating Costs of Hybrid-Electric and Conventional School Buses

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Journal of Transportation Technologies 2012年第2期2卷 158-164页

作者： Shauna Hallmark Robert Sperry center for Transportation research and Education Iowa State University Ames USA

Hybrid-electric school buses became available in the US through a national consortium designed to bring hybrid-electric school buses to market by creating enough demand among school districts to encourage manufacturers to invest in development of the technology. A number of school districts in the US joined the HESB project to purchase plug-in hybrid-electric school buses. Sixteen hybrid-electric school buses were purchased and piloted in 11 states. Two of the hybrid-electric school buses were purchased by the Nevada and Sigourney school districts in the state of Iowa, US. In-use fuel economy and electricity operating costs were monitored for the two Iowa hybrid school buses and two control buses (one in each district). Fuel consumption and other operational metrics were calculated and compared for each school district. The hybrid buses were deployed in January 2008 and data were recorded through May 2010. Valuation of the data indicated that the Nevada HESB had 29.6% better fuel economy than the control bus and the Sigourney HESB had 39.2% better fuel economy than the control bus. Electrical costs per mile were also calculated for the two hybrid-electric school buses. Total operating costs per mile were calculated based on fuel use per mile for all buses and electrical costs for the hybrid-electric school buses. The cost to operate the hybrid bus in Nevada was 37 cents/mile while the control bus cost 42 cents/mile, making the hybrid bus 13% less expensive to operate. The hybrid bus in Sigourney was 27 cents/mile while the control bus was 34 cents/mile, making the hybrid bus 21% less expensive to operate. All values are in US dollars.

关键词： Hybrid Vehicles Fuel Consumption School Bus Energy

Deep Multiview Image Fusion for Soybean Yield Estimation in Breeding Applications

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Plant Phenomics 2021年第1期3卷 286-297页

作者： Luis GRiera Matthew ECarroll Zhisheng Zhang Johnathon MShook Sambuddha Ghosal Tianshuang Gao Arti Singh Sourabh Bhattacharya Baskar Ganapathysubramanian Asheesh K.Singh Soumik Sarkar Department of Mechanical Engineering Iowa State UniversityAmesIowaUSA Department of Agronomy Iowa State UniversityAmesIowaUSA Department of Computer Science Iowa State UniversityAmesIowaUSA

Reliable seed yield estimation is an indispensable step in plant breeding programs geared towards cultivar development in major row *** objective of this study is to develop a machine learning(ML)approach adept at soybean(Glycine max L.(Merr.))pod counting to enable genotype seed yield rank prediction from in-field video data collected by a ground *** meet this goal,we developed a multiview image-based yield estimation framework utilizing deep learning *** images captured from different angles were fused to estimate the yield and subsequently to rank soybean genotypes for application in breeding *** used data from controlled imaging environment in field,as well as from plant breeding test plots in field to demonstrate the efficacy of our framework via comparing performance with manual pod counting and yield *** results demonstrate the promise of ML models in making breeding decisions with significant reduction of time and human effort and opening new breeding method avenues to develop cultivars.

关键词： breeding soybean cultivar