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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

Background: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

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Effects of smelting parameters on the slag/metal separation behaviors of Hongge vanadium-bearing titanomagnetite metallized pellets obtained from the gas-based direct reduction process

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International Journal of Minerals,Metallurgy and Materials 2018年第6期25卷 609-622页

作者： Cong Feng Man-sheng Chu Jue Tang Zheng-gen Liu School of Metallurgy Northeastern University

Smelting separations of Hongge vanadium-bearing titanomagnetite metallized pellets（HVTMP）prepared by gas-based direct reduction were investigated,and the effects of smelting parameters on the slag/metal separation behaviors were *** mechanisms were elucidated using X-ray diffraction analysis,FACTSAGE 7.0 calculations,and scanning electron microscopy *** results show that,when the smelting temperature,time,and C/O ratio are increased,the recoveries of V and Cr of HVTMP in pig iron are improved,the recovery of Fe initially increases and subsequently decreases,and the recovery of Ti O_2 in slag *** the smelting Ca O/Si O_2 ratio is increased,the recoveries of Fe,V,and Cr in pig iron increase and the recovery of Ti O_2 in slag initially increases and subsequently *** appropriate smelting separation parameters for HVTMP are as follows：smelting temperature of 1873 K;smelting time of 30–50 min;C/O ratio of 1.25;and Ca O/Si O_2 ratio of *** these optimized parameters（smelting time：30 min）,the recoveries of Fe,V,Cr,and Ti O_2 are 99.5%,91.24%,92.41%,and 94.86%,respectively.

关键词： titanomagnetite vanadium chromium metallized pellets smelting separation recovery

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Allelopathic effects of extracts from Solidago canadensis L. against seed germination and seedling growth of some plants

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Journal of Environmental Sciences 2006年第2期18卷 304-309页

作者： SUN Bing-yao TAN Jian-zhong WAN Zhi-gang GU Fu-gen ZHU Ming-de College of Life Sciences Suzhou University Suzhou 215123 China School of Urbanology Suzhou University Suzhou 215123 China

To investigate the potential role of allelopathy in plant interference and in the successful invasion of alien species Solidago canadensis, aqueous and ethanolic extracts from rhizomes, stems and leaves of S. canadensis were prepared and used as treatment solutions to assess their effects on seed germination and seedling growth in four target species, mulberry （Morus alba）; morning glory （Pharbitis nil）, wheat （Triticum aestivum） and rape （Brassiea campestris）. Reduction and/or growth in germination and growth of the target plant species in the presence of both aqueous and ethanolic extracts at different concentrations indicated that the responses were species-specific and concentration-dependent. generally, ethanolic extracts （especially from leaves） imposed stronger effects on both seed germination and seedling growth. Extracts with lower concentration at 0.001 g/ml dw could stimulate the seedling growth of rape and morning glory, whereas extracts at any given concentrations have inhibitory effects on wheat and mulberry. It is suggested that the aqueous and ethanolic extracts of all the three parts of S. canadensis have significant allelopathic effects. Although both inhibition and stimulation occurred in the germination and growth of the target species, extracts with higher concentrations definitely inhibit seed germination and seedling growth of all target plants. We suggest that allelopathy plays a more important role than other mechanisms do in the out-competition ofS. canadensis over other plants, and make it invasive in new habitats.

关键词： canada goldenrod(Solidago cancutensis L.) allelopathy extracts seed germination seedling growth

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Flow-visualization and numerical investigation on the optimum design of cavitating jet nozzle

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Petroleum Science 2022年第5期19卷 2284-2296页

作者： Xiao-Ya Wu Yi-Qun Zhang Ya-Wen Tan gen-Sheng Li Ke-Wen Peng Bo Zhang State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum-BeijingBeijing 102249China Guangdong Provincial Key Laboratory of Distributed Energy Systems Dongguan University of TechnologyDongguan 523808GuangdongChina Department of Civil and Environmental Engineering University of AlbertaEdmontonAlberta T6G 2G7Canada

Cavitating jet is widely used in drilling,rock cutting and ocean re source exploitation because of its stro ng erosion *** analysis of the relationship between the flow characteristics and the structure of cavitating jet nozzle is ***,we utilized 3 D printed technology and high-speed photography to design visualization experime nts to analyse the impact of the variation of resonator and throat size of the organ-pipe self-resonating cavitating nozzles on the cavitation characteristics through image *** velocity field,pressure field and vapor volume fraction injected by the nozzle were taken as the objective functions to study the influence of different structural parameters on the cavitation effect based on FLUENT 19.0 software,and the results were compared with the experimental *** results show that increasing the length and diameter of the resonator contributes to the occurrence of cavitation and the structure stability of the flow ***,excessive size affects self-resonant of the nozzle and makes it difficult to form resonance *** this study,the optimal values of nozzle throat length and divergent angle are twice the throat diameter and 40°,*** research provides an integrated research method to study the optimization of self-resonating nozzle and cavitating jet characteristics.

关键词： Cavitating jet Self-resonating cavitating nozzle Visualization Computational fluid dynamics Structure optimization

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Spectral Properties of Fabry-Pérot Laser Diodes and Conventional Semiconductor Optical Amplifiers

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The Journal of China Universities of Posts and Telecommunications 2006年第1期13卷 63-66页

作者： CHEN gen-xiang LI Wei XU Cheng-lin HUANG Wei-ping JIAN Shui-sheng Key Laboratory of All Optical and Advanced Telecommunication Networks Beijing Jiaotong University Beijing 100044 P.R. China Department of Chemical and Engineering Physics University of Wisconsin-PlatteviUe Platteville 53818 WI USA Department of Electrical and Computer Engineering McMaster University Hamilton I..8S 4K1 Ontario Canada

This paper presents an unified comprehensive model for the analysis of the spectral properties of Fabry-Perot laser diodes and conventional semiconductor optical amplifiers. We develop the model by considering the wide-band amplified spontaneous emission fields and the input optical signal fields in a general frame. Specifically, this paper discusses theoretical aspects of the model in details, which are based upon the spectra of material gain and spontaneous emission power, nonlinear gain suppression, and longitudinal spatial hole burning. This paper also presents simulation results of the model for the case of conventional semiconductor optical amplifier and the case of Fabry-Perot laser diode to demonstrate its capabilities.

关键词： semiconductor optical amplifier laser diode amplified spontaneous emission traveling-wave model

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The Prevalence, genetic Characterization, and Evolutionary Analysis of Porcine Pegivirus in Guangdong, China

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Virologica Sinica 2021年第1期36卷 52-60页

作者： Yongsheng Xie Xiaoru Wang Junsen Feng Liuming Wei gen Li Guangbin Si Yibo Chen He Yan Dongsheng He College of Veterinary Medicine South China Agricultural UniversityGuangzhou 510642China School of Food Science and Engineering South China University of TechnologyGuangzhou 510641China

Porcine pegivirus(PPgV)is a member of the Pegivirus genus in the Flaviviridae *** V is an emerging virus that has been discovered in swine herds in Germany,the United States,China,Poland,Italy,and the United Kingdom,indicating a wide geographical *** this retrospective study,339 pig serum samples were collected from 20 different commercial swine farms located in nine cities in Guangdong Province,China,from 2016 to 2018,to investigate the prevalence and genetic diversity of PPg V in this geographical *** V was detected in 55%(11/20)of the farms using nested reverse transcription PCR,with 6.2%(21/339)of pigs testing positive for PPg *** yearly PPg V-positive rate increased from 2.6%to 7.5%between 2016 and *** of PPg V-positive samples identified two complete polyprotein genes and seven partial NS5 B genes from different *** analysis of the polyprotein genes revealed that PPg V sequences obtained in this study showed 87.4%–97.2%similarity at the nucleotide level and 96.5%–99.4%similarity at the amino acid level with the reference *** alignment and phylogenetic analysis of the complete polyprotein gene and partial NS5 B and NS3 genes demonstrated a high genetic similarity with the samples from the *** finding of the wide distribution of PPg V in swine herds in Guangdong Province will contribute to the understanding of the epidemiological characteristics and genetic evolution of PPg V in China.

关键词： Porcine pegivirus(PPgV) Prevalence genetic diversity Phylogenetic analysis Guangdong Province

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Impact of Long-Term Fertilization on Community Structure of Ammonia Oxidizing and Denitrifying Bacteria Based on amoA and nirK genes in a Rice Paddy from Tai Lake Region,China

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Journal of Integrative Agriculture 2014年第10期13卷 2286-2298页

作者： JIN Zhen-jiang LI Lian-qing LIU Xiao-yu PAN gen-xing Qaiser Hussein LIU Yong-zhuo Institute of Resource Ecosystem and Environment of AgricultureNanjing Agricultural University Guilin University of Technology

Ammonia oxidizing （AOB） and denitrifying bacteria （DNB） play an important role in soil nitrogen transformation in natural and agricultural ecosystems. Effects of long-term fertilization on abundance and community composition of AOB and DNB were studied with targeting ammonia monooxygenase （amoA） and nitrite reductase （nirK） genes using polymerase chain reaction- denaturing gradient gel electrophoresis （PCR-DGGE） and real-time PCR, respectively. A field trial with different fertilization treatments in a rice paddy from Tai Lake region, centre East China was used in this study, including no fertilizer application （NF）, balanced chemical fertilizers （CF）, combined organic/inorganic fertilizer of balanced chemical fertilizers plus pig manure （CFM）, and plus rice straw return （CFS）. The abundances and riehnesses of amoA and nirK were increased in CF, CFM and CFS compared to NF. Principle component analysis of DGGE profiles showed significant difference in nirK and amoA genes composition between organic amended （CFS and CFM） and the non-organic amended （CF and NF） plots. Number of amoA copies was significantly positively correlated with normalized soil nutrient richness （NSNR） of soil organic carbon （SOC） and total nitrogen （T-N）, and that of nirK copies was with NSNR of SOC, T-N plus total phosphorus. Moreover, nitrification potential showed a positive correlation with SOC content, while a significantly lower denitrification potential was found under CFM compared to under CFS. Therefore, SOC accumulation accompanied with soil nutrient richness under long-term balanced and organic/inorganic combined fertilization promoted abundance and diversity of AOB and DNB in the rice paddy.

关键词： long-term fertilization ammonia oxidizing bacteria denitrifying bacteria abundance rice paddy

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Pore structure and tracer migration behavior of typical American and Chinese shales

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Petroleum Science 2015年第4期12卷 651-663页

作者： Qin-Hong Hu Xian-Guo Liu Zhi-Ye Gao Shu-gen Liu Wen Zhou Wen-Xuan Hu China University of Geosciences (Wuhan) The University of Texas at Arlington State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Chengdu University of Technology Nanjing University

With estimated shale gas resources greater than those of US and canada combined, China has been embarking on an ambitious shale development program. However, nearly 30 years of American experience in shale hydrocarbon exploration and production indicates a low total recovery of shale gas at 12 %-30 % and tight oil at 5 %-10 %. One of the main barriers to sustainable devel- opment of shale resources, namely the pore structure （ge- ometry and connectivity） of the nanopores for storing and transporting hydrocarbons, is rarely investigated. In this study, we collected samples from a variety of leading hydrocarbon-producing shale formations in US and China. These formations have different ages and geologic char- acteristics （e.g., porosity, permeability, mineralogy, total organic content, and thermal maturation）. We studied their pore structure characteristics, imbibition and saturated diffusion, edge-accessible porosity, and wettability with four complementary tests： mercury intrusion porosimetry, fluid and tracer imbibition into initially dry shale, tracer diffusion into fluid-saturated shale, and high-pressure Wood＇s metal intrusion followed with imaging and ele- mental mapping. The imbibition and diffusion tests use tracer-bearing wettability fluids （API brine or n-decane） to examine the association of tracers with mineral or organic matter phases, using a sensitive and micro-scale elemental laser ablation ICP-MS mapping technique. For two molecular tracers in n-decane fluid with the estimated sizes of 1.39 nm x 0.29 nm x 0.18 nm for 1-iododecane and 1.27 nm ~ 0.92 nm ~ 0.78 nm for trichlorooxobis （triph- enylphosphine） rhenium, much less penetration was observed for larger molecules of organic rhenium in shales with median pore-throat sizes of several nanometers. This indicates the probable entanglement of sub-nano-sized molecules in shales with nano-sized pore-throats. Overall findings from the above innovative approaches indicate the limited accessibility （several

关键词： Shale - Nanopore - Connectivity - Diffusion Imbibition

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生铁遗传性对球墨铸铁性能的影响

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铸造设备与工艺 2024年第3期 79-84页

作者：李晓艳赵培根马宏军杨麟俞健良宁波日月重工股份有限公司浙江宁波315113 宁波明凌科技有限公司浙江宁波315700 宁波日星铸业有限公司浙江宁波315700

研究了同样的炉料配比情况下,生铁种类对球磨铸铁性能的影响。试验浇注温度为1340℃~1350℃,浇注边长250 mm的立方块,观察其显微组织,并进行性能测试。结果表明:相同生产条件下,不同生铁在占比相同的情况下,其自身组织形态对球墨铸铁的... 详细信息

研究了同样的炉料配比情况下,生铁种类对球磨铸铁性能的影响。试验浇注温度为1340℃~1350℃,浇注边长250 mm的立方块,观察其显微组织,并进行性能测试。结果表明:相同生产条件下,不同生铁在占比相同的情况下,其自身组织形态对球墨铸铁的石墨大小、球化率、组织及性能有明显的差异,其中石墨球数量与低温冲击性能的影响程度最大,A、B、C、D生铁的边缘与心部每平方毫米石墨跨度分别在10~25与20~35两区间。

关键词：球墨铸铁生铁种类显微组织组织形态石墨大小球化率

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Diagnosis and Prevention of Swine Influenza

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Animal Husbandry and Feed Science 2009年第6期1卷 27-33,46页

作者： HU Lai-gen Nanjing Tech-Bank Bio-industry Co. LTD Nanjing 210001 China

Swine influenza （SI） is an acute, febrile, highly contagious, respiratory infectious disease caused by swine influenza virus （SIV）, which is a common disease in intensive pig farms, and prevalent throughout the world. Disease in affected pigs was characterized by burst, high fever, rapid epidemic spread. The mortality of SI with secondary or mixed infection could be increased. Moreover, more researches showed that the outbreaks of human influenza are associated with the outbreak of swine influenza, and there are a striking parallel nature and relevance. In the present article, the pathogen, epidemiology, diagnosis, treatment and public health aspects were elaborated, so as to provide a reference for scientific prevention and treatment of SI.

关键词： Swine influenza Epidemiology Diagnosis Treatment Public health security

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