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| 1 | Enhancement of High Energy Electron Fluxes and Variation of Atmospheric Electric Field in the Antarctic Region显示文摘High-energy electron precipitation in the high latitude regions enhances the ionization of the atmosphere,and subsequently increases the atmospheric conductivities and the vertical electric field of the atmosphere near the ground as well.The High-Energy Electron Flux(HEEF) data measured by the Fengyun-3 meteorological satellite are analyzed together with the data of nearsurface atmospheric vertical electric field measured at the Russian Vostok Station.Three HEEF enhancements are identified and it is shown that when the HEEF increases to a certain level,the local atmospheric vertical electric field near the ground can increase substantially than usual.The response time of the electric field to HEEF enhancement is about 3.7 to 4 days. | LI Renkang CHEN Tao LUO Jing ZHOU Limin HE Zhaohai WANG Chunqin SUN Yueqiang | 2016 | 空间科学学报2016，36，1： | 8 |
| 2 | Dietary Bacillus spp.enhanced growth and disease resistance of weaned pigs by modulating intestinal microbiota and systemic immunity显示文摘Background:Previous research has shown that dietary supplementation of Bacillus spp.probiotics exerts beneficial effects on animals’growth.However,limited studies have evaluated the efficacy of Bacillus spp.on weaned pigs and their effects on host gut health and microbiome,and systemic immunity using a disease challenge model.The objective of this experiment was to investigate the effects of two Bacillus spp.strains(Bacillus subtilis DSM 32540 and Bacillus pumilus DSM 32539)on growth performance,diarrhea,intestinal health,microbiome,and systemic immunity of weaned pigs experimentally infected with an enterotoxigenic Escherichia coli(ETEC).Results:Pigs in PRO1(Bacillus subtilis DSM 32540)had greater(P<0.05)body weight on d 7 and 14 PI,greater(P<0.05)ADG from d 0 to 7 and d 7 to 14 PI,compared with pigs in CON(Control).Pigs in PRO1 had milder(P<0.05)diarrhea on d 2 and 3 PI compared with pigs in CON.However,no differences were observed in growth performance and diarrhea score between PRO2(Bacillus pumilus DSM 32539)and CON groups.Supplementation of PRO1 decreased(P<0.05)lymphocyte counts on d 7 and 14 PI,compared with CON.Supplementation of PRO1 and PRO2 both reduced(P<0.05)total coliforms in mesenteric lymph nodes on d 21 PI.Pigs in PRO2 had greater(P<0.05)goblet cell number and sulfomucin percentage in duodenal villi and greater(P<0.05)sialomucin percentage in jejunal villi than pigs in CON.Supplementation of PRO1 up-regulated(P<0.05)MUC2 gene expression in jejunal mucosa and reduced(P<0.05)PTGS-2 and IL1B gene expression in ileal mucosa on d 21 PI,compared with CON.Pigs in PRO1 had reduced(P<0.05)relative abundance of families Lachnospiraceae,Peptostreptococcaceae and Pasteurellaceae in the ileum.Conclusions:Supplementation of Bacillus subtilis DSM 32540 improved growth performance,alleviated diarrhea severity,enhanced gut health,and reduced systemic inflammation of weaned pigs infected with ETEC F18.Although Bacillus pumilus DSM 32539 was able to alleviate systemic inflammation,it had limited impacts on growth performance and severity of diarrhea of ETEC F18 challenged weaned pigs. | Yijie He Cynthia Jinno Kwangwook Kim Zhaohai Wu Bie Tan Xunde Li Rose Whelan Yanhong Liu | 2021 | Journal of Animal Science and Biotechnology2021，12，2： | 2 |
| 3 | Characteristics of low altitude ionospheric electric field over Hainan Island,China显示文摘A sounding rocket experiment undertaken by the Chinese Meridian Project from a low latitude station on Hainan Island(19.5°N,109.1°E),China,measured the DC electric field during 05:45-05:52 LT on April 5,2013.The data observed using a set of electric field double probes,as part of the rocket's scientific payload,revealed the special profile of how the vectors of the DC electric field vary with altitude between 130 and 190 km.During the experiment,the vertical electric field was downward,and the maximum vertical electric field was nearly 5.1 mV/m near the altitude of 176 km.The zonal electric field was eastward and slightly less than 0.6 mV/m.The plasma drift velocity was estimated from the E×B motion,and the zonal drift velocity was eastward and of the order of 100 m/s.The zonal wind velocity was also estimated using the drift velocity near the maximum density height in the F1-region,and it was found to be nearly 120 m/s.This work constituted the first in situ measurement of the DC electric field conducted within the Fl-region(between 130 and 190 km) in the East Asian Sector. | LI RenKang CHEN Tao MAN Feng JIANG XiuJie LUO Jing HE ZhaoHai ZHANG HuiMing WANG LinFeng LIU Cheng Francisco Carlos de MENESES WANG GuoJun XU JiYao | 2017 | Science China Earth Sciences2017，60，4： | 1 |
| 4 | Ion flux dropout observed near dipolarization front显示文摘An ion flux dropout near the dipolarization front(DF) at around XGSM=-11 REin the Earth's plasma sheet was observed by Time History of Events and Macroscale Interaction during substorms(THEMIS) on March31, 2009. The ion differential energy fluxes at energies from 450 e V to 150 ke V measured by the ESA and SST instruments from THC began to decrease about 2 s before the detection of the DF and reached a local minimum 6 s later. Then, the ion fluxes gradually increased to form a dropout around the DF. The spatial extent of the dropout was about 4,000 km. For energies above 20 ke V, the ion fluxes after the dropout are greater than those before it,contrary to the fluxes at energies below 20 ke V. The associated ion density variation indicates that the ion flux dropout coincides with the ion density dropout. Taking advantage of multipoint observations, THD, THC, and THE detected the same DF consecutively. Only THC detected an obvious ion flux dropout; THD observed an indistinct one about 2 s before THC; no high-energy(E [ 30 ke V) ion flux dropout was observed by THE. Our study suggests that the ion flux dropout may evolve withthe earthward-propagating DF, and its properties can depend on locations relative to the DF. | Xueling Shi Tao Chen Lingqian Zhang Suping Duan Jiang Liu Zhaohai He | 2014 | Chinese Science Bulletin2014，59，34： | 1 |
| 5 | Double Star TC-1 observation of the earthward flowing plasmoids in the near magnetotail显示文摘We analyze Double Star TC-1 magnetic field data from July to September in 2004 and find that plas-moids exist in the very near-Earth magnetotail. It is the first time that TC-1 observes the plasmoids inthe magnetotail at X > ?13 RE. According to the difference of the magnetic field structure in plasmoids,we choose two typical cases for our study: the magnetic flux rope on August 6 with the open magneticfield and the magnetic loop on September 14 with the closed magnetic field. Both of the cases are as-sociated with the high speed earthward flow and the magnetic loop is related to a strong substorm. Theions can escape from the magnetic flux rope along its open field line, but the case of the closed mag-netic loop can trap the ions. The earthward flowing plasmoids observed by TC-1 indicate that the mul-tiple X-line magnetic reconnection occurs beyond the distance of X=?10 RE from the earth. | ZHANG YongCun LIU ZhenXing SHEN Chao DUAN SuPing HE ZhaoHai C M CARR H REME | 2007 | Chinese Science Bulletin2007，52，13： | 1 |
| 6 | Characteristics of magnetic dipolarizations in the vicinity of the substorm onset region observed by THEMIS显示文摘With conjunction observations of electromagnetic fields and plasma from Time History of Events and Macroscale Interactions during Substorm(THEMIS)in the near-Earth magnetotail,we investigate the spatial and temporal properties of substorm dipolarizations in the near-Earth plasma sheet(NEPS)during a substorm at 03:23 UT on 12 February 2008.Substorm dipolarizations with different features are detected by three near-Earth THEMIS probes(THA(P5),THD(P3)and THE(P4))in the magnetotail.In the current sheet with a large plasma beta value(β>2,whereβis the ratio of the plasma thermal pressure to the magnetic pressure),the dipolarization within the substorm onset region,(−10.4,2.8,−2.6)RE_gsm,has a large initial magnetic field elevation angle,θ>60°,θ=arctan(Bz/(Bx2+By2)1/2),and is accompanied by energetic ion(tens to hundred keV)dispersionless injection detected by THD(P3).This substorm onset dipolarization is characterized by Bx and By components around 0 nT with significant fluctuations.The Bz component increases sharply and its subsequent magnitude approaches the total magnetic field,Bt.The maximum value of the elevation angle approaches 85°during the later substorm expansion phase.In the NEPS withβ~1,the dipolarization outside the substorm onset region is characterized by a magnetic elevation angle with a small beginning value ofθ<45°and following multi-step enhancements during the substorm expansion phase.The maximum value of the elevation angle approaches to 70°during the later substorm expansion phase.Our observation results indicate that characteristics of dipolarization with a large beginning elevation angle within the substorm onset region provide a new indicator to identify substorm onset location. | SuPing Duan Chi Wang Weining William Liu ZhaoHai He | 2021 | Earth and Planetary Physics2021，5，3： | 1 |
| 7 | Tributyrin administration improves intestinal development and health in pre-weaned dairy calves fed milk replacer显示文摘Butyrate and its derivatives possess various nutritional and biological benefits for mammals,whereas its effects on dairy calves have not been well characterized.This study evaluated the effects of tributyrin administration on blood immune,intestinal immune and barrier functions,and microbial composition of pre-weaned dairy calves.Twenty newborn Holstein bull calves were randomly assigned into a control group(no tributyrin supplementation,CON;n=10)or a treatment group(supplemented with tributyrin at 2 g/L of milk,TRB;n=10).The results showed that diarrhea frequency was decreased significantly by tributyrin administration from d 29 to 56(P<0.001)and the whole period(P=0.003,d 1 to 56)though no significant effects were observed on growth performance.For blood metabolites,tributyrin administration significantly reduced the concentration of interleukin-1b(IL-1b)on d 28(P=0.001)and tended to reduce the concentration of serum amyloid A on d 56(P=0.079),whereas serum oxidative status parameters were not affected.For intestinal development,tributyrin administration increased the villus height(P<0.001)and the ratio of villus height to crypt depth(P=0.046)in the jejunum,and the villus height in the ileum(P=0.074).Furthermore,toll-like receptor 2(TRL2,P=0.045)and IL-1b(P=0.088)gene expressions were downregulated,while claudin-4(P=0.022)gene expression was upregulated in the jejunum following tributyrin administration.In the ileum,claudin-4(P=0.029)and G-protein coupled receptor 41(P=0.019)gene expressions were upregulated in the TRB group compared to CON.No significantly higher abundances of microbiota were found in the jejunum or ileum of calves in the CON group.In the TRB group,supplementing tributyrin significantly increased the abundance of shortchain fatty acid(SCFA)-producing bacteria,including Ruminococcaceae,Lachnospiraceae,Prevotella and Rikenellaceae(LDA>3.5,P<0.05),which was negatively associated with inflammatory gene expression(TLR2 and IL-1b)but positively associated with intestinal barrier genes(claudin-4)and morphological parameters(P<0.05).In conclusion,supplementing tributyrin in milk replacer could improve intestinal development and health of pre-weaned dairy calves by stimulating SCFA-producing bacteria colonization,enhancing intestinal barrier functions and suppressing inflammatory responses. | Shuai Liu Junda Wu Zhaohai Wu Gibson Maswayi Alugongo Muhammad Zahoor Khan Jinghui Li Jianxin Xiao Zhiyuan He Yulin Ma Shengli Li Zhijun Cao | 2022 | Animal Nutrition2022，，3： | 0 |
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