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26篇 您的检索式:作者名="Xiangfang Zeng"
    题名 作者 年代 出处 被引量
1Novel metabolic and physiological functions of branched chain amino acids: a review显示文摘It is widely known that branched chain amino acids(BCAA) are not only elementary components for building muscle tissue but also participate in increasing protein synthesis in animals and humans. BCAA(isoleucine, leucine and valine) regulate many key signaling pathways, the most classic of which is the activation of the m TOR signaling pathway. This signaling pathway connects many diverse physiological and metabolic roles. Recent years have witnessed many striking developments in determining the novel functions of BCAA including:(1) Insufficient or excessive levels of BCAA in the diet enhances lipolysis.(2) BCAA, especially isoleucine, play a major role in enhancing glucose consumption and utilization by up-regulating intestinal and muscular glucose transporters.(3)Supplementation of leucine in the diet enhances meat quality in finishing pigs.(4) BCAA are beneficial for mammary health, milk quality and embryo growth.(5) BCAA enhance intestinal development, intestinal amino acid transportation and mucin production.(6) BCAA participate in up-regulating innate and adaptive immune responses.In addition, abnormally elevated BCAA levels in the blood(decreased BCAA catabolism) are a good biomarker for the early detection of obesity, diabetes and other metabolic diseases. This review will provide some insights into these novel metabolic and physiological functions of BCAA.Shihai Zhang Xiangfang Zeng Man Ren Xiangbing Mao Shiyan Qiao 2017Journal of Animal Science and Biotechnology2017,8,3:28
2A shallow aftershock sequence in the north-eastern end of the Wenchuan earthquake aftershock zone显示文摘Previous studies show that mature faults are filled with fault gouge in the shallow part and thus cannot accumulate enough strain energy for earthquakes. Therefore most earthquakes are deeper than 5 km, except those events occurring on new faults or in intact rocks. From field observation, Wenchuan earthquake is found to rupture the free surface about 200 km, but the rupture may extend underground much further from teleseismic body waves inversion and aftershocks distribution. In the northeastern end of the rupture zone, deep rupture may induce stress increase near the free surface, and trigger shallow earthquakes. An Ms 5.7 aftershock occurred at Qingchuan, northeast end of Wenchuan earthquake fault on July 24, 2008, featuring thrust mechanism with a 3 km source centroid depth. The shallow focal depth is confirmed with the sPL phase recorded at station L0205. As Rayleigh wave is well only developed for source depth less than 1/5 of epicentral distance, the observed large amplitude of Rg at a distance of 15 km implied depth of 3 km or less. Dozens of aftershocks' sPL waveforms are also analyzed to confirm the source depths less than 3 km. On the other hand, no surface ruptures are found by geological survey or InSAR studies. It is strongly suggested that these aftershock sequences initiate fresh rupture in intact rocks triggered by stress increase from the deep co-seismic rupture of the Wenchuan mainshock.Luo Yan Ni SiDao Zeng XiangFang Zheng Yong Chen QiFu Chen Yong 2010Science China Earth Sciences2010,53,11:26
3Focal mechanisms of the Lushan earthquake sequence and spatial variation of the stress field显示文摘Using broadband seismic records from regional networks, we determined the focal mechanisms and depths of 37 earthquakes in the 2013 M7.0 Lushan earthquake sequence(3.4≤Mw≤5.1) by fitting the three-component waveform data. The results show that the earthquakes are predominantly thrust events, with occasional strike-slip mechanisms. Most earthquakes occurred at depths of 10–20 km. We derived the regional distribution of the average stress field in this area using the damped linear inversion method and the focal mechanisms obtained in this study. The inversion results suggest that the Lushan region and the adjacent area are mostly under compression. The orientations of the maximum principal axes trend NW-SE, with some local differences in the stress distribution at different depths. Compared with the distribution of the stress field in the Wenchuan earthquake area, the stress field in the southwest section of the Longmenshan Fault zone(LFZ) share similar characteristics, predominantly thrust faulting with a few strike-slip events and the maximum compression axes being perpendicular to the LFZ.LUO Yan ZHAO Li ZENG XiangFang GAO Yuan 2015Science China Earth Sciences2015,58,7:24
4Advances in low-protein diets for swine显示文摘Recent years have witnessed the great advantages of reducing dietary crude protein(CP) with free amino acids(AA)supplementation for sustainable swine industry, including saving protein ingredients, reducing nitrogen excretion, feed costs and the risk of gut disorders without impairing growth performance compared to traditional diets. However, a tendency toward increased fatness is a matter of concern when pigs are fed low-protein(LP) diets. In response, the use of the net energy system and balanced AA for formulation of LP diets has been proposed as a solution. Moreover, the extent to which dietary CP can be reduced is complicated. Meanwhile, the requirements for the first five limiting AA(lysine, threonine, sulfur-containing AA, tryptophan, and valine) that growing-finishing pigs fed LP diets were higher than pigs fed traditional diets, because the need for nitrogen for endogenous synthesis of non-essential AA to support protein synthesis may be increased when dietary CP is lowered. Overall, to address these concerns and give a better understanding of this nutritional strategy, this paper reviews recent advances in the study of LP diets for swine and provides some insights into future research directions.Yuming Wang Junyan Zhou Gang Wang Shuang Cai Xiangfang Zeng Shiyan Qiao 2018Journal of Animal Science and Biotechnology2018,9,4:23
5Study and use of the probiotic Lactobacillus reuteri in pigs:a review显示文摘Probiotics are living microorganisms that provide a wide variety of health benefits to the host when ingested in adequate amounts.The bacterial strains most frequently used as probiotic agents are lactic acid bacteria,such as Lactobacillus reuteri,which is one of the few endogenous Lactobacillus species found in the gastrointestinal tract of vertebrates,including humans,rats,pigs and chickens.L reuteri is one of the most well documented probiotic species and has been widely utilized as a probiotic in humans and animals for many years.Initially,L reuteri was used in humans to reduce the incidence and the severity of diarrhea,prevent colic and necrotic enterocolitis,and maintain a functional mucosal barrier.As interest in alternatives to in-feed antibiotics has grown in recent years,some evidence has emerged that probiotics may promote growth,improve the efficiency of feed utilization,prevent diarrhea,and regulate the immune system in pigs.In this review,the characteristics of L reuteri are described,in order to update the evidence on the efficacy of using L.reuteri in pigs.Chengli Hou Xiangfang Zeng Fengjuan Yang Hong Liu Shiyan Qiao 2016Journal of Animal Science and Biotechnology2016,7,1:19
6The M5.0 Suining-Tongnan (China) earthquake of 31 January 2010:A destructive earthquake occurring in sedimentary cover显示文摘Usually, only crystalline basement is strong enough to store the massive strain energy that can be released in a damaging earthquake. By contrast, sedimentary cover is weak, because of its relatively high porosity and fluids. Therefore, it generally cannot accumulate enough energy for strong earthquakes. On January 31, 2010, a M5.0 earthquake occurred near the border of Suining and Tongnan in China. It excited strong short-period Rayleigh waves Rg, indicative of its shallow focal depth. The focal depth is constrained to less than 4 km, most probably in the range of 1-3 km, by modeling amplitude dependence on the frequency and waveforms of teleseismic depth phases (pP, sP). Because the local Mesozoic sedimentary cover is about 6 km thick, this earthquake should have occurred in the sedimentary cover. Though some shallow earthquakes with magnitudes up to M4 occur in Paleozoic sediments, this earthquake is the first M5 event studied in Mesozoic sedimentary cover. This event provides a rare opportunity to study seismogenic processes of damaging earthquakes in sedimentary basins.LUO Yan NI SiDao ZENG XiangFang XIE Jun CHEN Yong LONG Feng 2011Chinese Science Bulletin2011,56,6:17
7Advances in research on solid-state fermented feed and its utilization:The pioneer of private customization for intestinal microorganisms显示文摘With sustainable development of biotechnology,increasing attention has been placed on utilization of solid-state fermented feed(SFF).Solid-state fermented feed has been a candidate strategy to alleviate the contradiction between supply and demand of feed resources,ensure food hygiene safety,promoting energy conservation,and emission reduction.In production of SFF,a variety of organic acids,enzymes,vitamins,peptides,and other unknown growth factors are produced,which could affect performance of animals.Solid-state fermented feed produced by different fermentation techniques has great instability on different physiological stages of different animals,which hinders the application and standardized production of SFF.Herein,we summarize the current advances in the role of the characteristics of SFF prepared by different manufacturing technique and its research progress in animal experiments on growth performance,gastrointestinal ecology,and immune system,so as to provide references for further acquiring a relatively perfect set of SFF production and evaluation systems.Lijie Yang Xiangfang Zeng Shiyan Qiao 2021Animal Nutrition2021,,4:14
8Comparison of ground truth location of earthquake from InSAR and from ambient seismic noise: A case study of the 1998 Zhangbei earthquake显示文摘Because ambient seismic noise provides estimated Green's function (EGF) between two sites with high accuracy, Rayleigh wave propagation along the path connecting the two sites is well resolved. Therefore, earthquakes which are close to one seismic station can be well located with calibration extracting from EGF. We test two algorithms in locating the 1998 Zhangbei earthquake, one algorithm is waveform-based, and the other is traveltime-based. We first compute EGF between station ZHB (a station about 40 km away from the epicenter) and five IC/IRIS stations. With the waveform-based approach, we calculate 1D synthetic single-force Green's functions between ZHB and other four stations, and obtain traveltime corrections by correlating synthetic Green's functions with EGFs in period band of 10-30 s. Then we locate the earthquake by minimizing the differential travel times between observed earthquake waveform and the 1D synthetic earthquake waveforms computed with focal mechanism provided by Global CMT after traveltime correction from EGFs. This waveform-based approach yields a location which error is about 13 km away from the location observed with InSAR. With the traveltime-based approach, we begin with measuring group velocity from EGFs as well as group arrival time on observed earthquake waveforms, and then locate the earthquake by minimizing the difference between observed group arrival time and arrival time measured on EGFs. This traveltime-based approach yields accuracy of 3 km, Therefore it is feasible to achieve GT5 (ground truth location with accuracy 5 km) with ambient seismic noises. The less accuracy of the waveform-based approach was mainly caused by uncertainty of focal mechanism.Jun Xie Xiangfang Zeng Weiwen Chen Zhongwen Zhan 2011Earthquake Science2011,24,2:7
9Imaging shallow structure with active-source surface wave signal recorded by distributed acoustic sensing arrays显示文摘Distributed acoustic sensing(DAS) is one recently developed seismic acquisition technique that is based on fiber-optic sensing. DAS provides dense spatial spacing that is useful to image shallow structure with surface waves.To test the feasibility of DAS in shallow structure imaging,the PoroTomo team conducted a DAS experiment with the vibroseis truck T-Rex in Brady's Hot Springs, Nevada, USA.The Rayleigh waves excited by the vertical mode of the vibroseis truck were analyzed with the Multichannel Analysis of Surface Waves(MASW) method. Phase velocities between5 and 20 Hz were successfully extracted for one segment of cable and were employed to build a shear-wave velocity model for the top 50 meters. The dispersion curves obtained with DAS agree well with the ones extracted from co-located geophones data and from the passive source Noise Correlation Functions(NCF). Comparing to the co-located geophone array, the higher sensor density that DAS arrays provides help reducing aliasing in dispersion analysis, and separating different surface wave modes. This study demonstrates the feasibility and advantage of DAS in imaging shallow structure with surface waves.Zhenghong Song Xiangfang Zeng Clifford H.Thurber Hebert F.Wang Dante Fratta 2018Earthquake Science2018,31,4:4
10Effects of L-lysine·H2SO4 product on the intestinal morphology and liver pathology using broiler model显示文摘Background: Lysine is used widely in livestock production due to the shortage of feed protein resources.Llysine·H2SO4 contains L-lysine sulphate as well as fermentation co-products which contain other amino acids and phosphorus.However,there are few articles about L-lysine·H2SO4 product regarding intestinal morphology and liver pathology of broiler chickens.In this article,we focus on the absorption and metabolism of L-lysine·H2SO4 revealed in the variation of intestinal morphology and liver pathology to determine the tolerance of chicks for L-lysine·H2SO4.Methods: To evaluate the tolerance of broilers for L-lysine·H2SO4,240 one day old broilers were allocated randomly to one of five dietary treatments which included corn-soybean diets containing 0,1%,4%,7% or 10% L-lysine·H2SO4(L-lysine content = 55%).Results: Supplementation of 1% L-lysine·H2SO4 in the diet had no negative effects.However,4%,7% or 10% Llysine·H2SO4 supplementation produced negative responses on broiler performance,carcass characteristics,blood biochemistry,and particularly on intestinal morphology and liver pathology compared with broilers fed the control diet.Conclusion: Our results show that supplementation with 1% L-lysine·H2SO4 had no negative effects on performance,carcass characteristics,blood biochemistry,intestinal morphology and liver pathology in broilers,but supplementation with 4%,7% or 10% L-lysine·H2SO4 produced a negative response,particularly with respect to intestinal morphology and liver pathology.Hongmin Jia Ting He Haitao Yu Xiangfang Zeng Shihai Zhang Wenfeng Ma Jie Zhang Shiyan Qiao Xi Ma 2019Journal of Animal Science and Biotechnology2019,10,3:3
11Crustal S-wave velocity structure of the Yellowstone region using a seismic ambient noise method显示文摘The Yellowstone volcano is one of the largest active volcanoes in the world,and its potential hazards demand detailed seismological and geodetic studies.Previous studies with travel time tomography and receiver functions have revealed a low-velocity layer in the crust beneath the Yellowstone volcano,suggesting the presence of a magma chamber at depth.We use ambient seismic noise from regional seismic stations to retrieve short-period surface waves and then study the shallow shear velocity structure of the Yellowstone region by surface wave dispersion analysis.We first obtained a crustal model of the area outside of the Yellowstone volcano and then constructed an absolute shear wave velocity structure in combination with receiver function results for the crust beneath the Yellowstone volcano.The velocity model shows a low-velocity layer with shear velocity at around1.3 km/s,suggesting that a large-scale magma chamber exists at shallow levels within the crust of the Yellowstone volcanic region.Yan Lü Sidao Ni Jun Xie Yingjie Xia Xiangfang Zeng Bin Liu 2013Earthquake Science2013,26,5:2
12Leucine Supplementation in a Chronically Protein-Restricted Diet Enhances Muscle Weight and Postprandial Protein Synthesis of Skeletal Muscle by Promoting the mTOR Pathway in Adult Rats显示文摘Bo Zhang Licui Chu Hong Liu Chunyuan Xie Shiyan Qiao Xiangfang Zeng 2017Engineering2017,3,5:2
13Specific roles of threonine in intestinal mucosal integrity and barrier function显示文摘MAO Xiangbing ZENG Xiangfang QIAO Shiyan 2011Frontiers in Bioscience (Elite Edition)2011,3,4:1
14Surface Wave Group Velocity Tomography Imaging from Ambient Noise for Fujian Province and Its Adjacent Areas显示文摘Two-month continuous waveforms of 108 broadband seismic stations in Fujian Province and its adjacent areas are used to compute noise cross-correlation function(NCF). The signal quality of NCF is improved via the application of time-frequency phase weighted stacking. The Rayleigh and Love waves group velocities between 1 s-20 s are measured on the symmetrical component of the NCF with the multiple filter method. More than 5,000 Rayleigh wave dispersion curves and about 4,000 Love wave dispersion curves are obtained and used to invert for group velocity maps. This data set provides about 50 km resolution that is demonstrated with checkerboard tests. Considering the off great circle effect in inhomogeneous medium, the ray path is traced based on the travel time field computed with a finite difference method. The inverted group velocity maps show good correlation with the geological features in the upper and middle crust. The Fuzhou basin and Zhangzhou basin showed low velocity on the short period group velocity maps. On the long period group velocity maps, the low velocity anomaly in the high heat flow region near Zhangzhou and clear velocity contrast across the Zhenghe-Dapu faults, which suggests that the Zhenghe-Dapu fault might be a deep fault.ZHANG Lina LUO Yan CHEN Zhiyong XIE Zhizhao ZHOU Lanjie ZENG Xiangfang 2019Earthquake Research in China2019,33,1:1
15Study and use of the probiotic Laetobacillus reuteri in pigs: a review 显示文摘Chengli Hou Xiangfang Zeng Fengjuan Yang 2015Journal of Animal Science and Biotechnology2015,6,14:1
16Study and use of the probiotic Lactobacillus reuteri in pigs:a review 显示文摘Chengli Hou Xiangfang Zeng Fengjuan Yang et d 2015Journal of Animal Science and Biotechnology2015,6,:1
17The April 24, 2013 Changning M_s4.8 earthquake: a felt earthquake that occurred in Paleozoic sediment显示文摘The dense broadband seismic network provides more high-quality waveform that is helpful to improve constraint focal depth of shallow earthquake. Many shallow earthquakes occurring in sediment were regarded as induced events. In Sichuan basin, gas industry and salt mining are dependent on fluid injection technique that triggers microseismicity. We adopted waveform inversion method with regional records to obtain focal mechanism of an Ms 4.8 earthquake at Changning. The result suggested that the Changning earthquake occurred at a ESE thrust fault, and its focal depth was about 3 km. The depth phases including teleseismic pP phase and regional sPL phase shows that the focal depth is about 2 km. The strong, shortperiod surface wave suggests that this event is a very shallow earthquake. The amplitude ratio between Rayleigh wave and direct S wave was also used to estimate the source depth of the mainshock. The focal depth(2–4 km) is far less than the depth of the sedimentary layer thickness(6–8 km) in epicentral region. It is close to the depth of fluid injection of salt mining, which may imply that this event was triggered by the industrial activity.Xiangfang Zeng Libo Han Yaolin Shi 2014Earthquake Science2014,27,1:1
18Estimated Green's function extracted from superconducting gravimeters and seismometers显示文摘Estimated Green's function (EGF) between stations has been extracted from ambient seismic noise, direct surface wave and coda waves. It is also confirmed by laboratory experiments on ultrasonics and theoretical derivations assuming diffusive wave field, equi-partition of modes or random sources on an enclosed surface. This method provides a new approach to study the crust and mantle structure at regional scale, continental scale and global scale. Following the achievements with seismometer records, the records of infrasonic station, hydrophone and microphone were also used to obtain the EGFs of different wave fields. Since superconducting gravimeter is a better long period instrument than regular seismometer, EGF at longer period is expected to be obtained with the cross correlation of gravity data. In this paper, we will show the EGFs extracted by cross-correlations between the superconducting gravimeters and the seismometers. Both the travel times and dispersion curves obtained from different data types are consistent. The result shows that it is possible to retrieve the deep structure by the cross correlation of gravity data.Xiangfang Zeng Zhongwen Zhan Yong Zheng 2011Earthquake Science2011,24,2:1
19Maternal sodium acetate supplementation promotes lactation performance of sows and their offspring growth performance显示文摘Milk yield and composition are critical determining factors for the early growth and development of neonates.The objective of this experiment was to comprehensively evaluate the effects of dietary sodium acetate(SA)supplementation on the milk yield and composition of sows and the growth performance of their offspring.A total of 80 sows(Landrace×Yorkshire,3 to 6 parity)were randomly assigned to 2groups(with or without 0.1%SA)from d 85 of gestation to d 21 of lactation.The result shows that maternal 0.1%SA supplementation significantly increased sows milk yield,milk fat,immunoglobulin A(IgA)and IgG content in milk(P<0.05),with the up-regulation of short-chain fatty acids receptors(GPR41 and GPR43)expression and the activation of mammalian target of rapamycin complex C1(mTORC1)signaling pathway.Consistently,in our in vitro experiment,SA also activated m TORC1signaling in porcine mammary epithelial cells(P<0.05).Furthermore,the improvement of milk quality and quantity caused by maternal SA supplementation led to the increase in body weight(BW)and average daily weight gain(ADG)of weaning piglets,with the improvement of gut health and colonization of the beneficial bacteria(P<0.05).In conclusion,maternal supplementation of 0.1%SA improved the lactation performance(milk yield and milk fat)of sows,possibly with the activation of GPR41/GPR43-mTORC1 signaling.Furthermore,enhanced milk quality improved growth performance,gut health and the colonization of beneficial microbial flora of their piglets.Yingao Qi Tenghui Zheng Siwang Yang Qianzi Zhang Baofeng Li Xiangfang Zeng Yongxing Zhong Fang Chen Wutai Guan Shihai Zhang 2023Animal Nutrition2023,,3:0
20运用26s定点持续脉动源的同步洲际地震台网显示文摘地震学的定量研究需要精确的仪器时钟。最近的研究进展表明,可利用背景噪声来检测存在软件/硬件问题的海底地震仪(OBS)或陆上地震仪的台站时钟漂移情况。在稀疏的全球地震台网尺度下,从背景噪声中提取的短周期(<20s)瑞利波信号相对较弱,应用时受到限制。位于几内亚湾的持续稳定的26s固定脉动源,辐射出较强的噪声信号,可以被全球台站记录到,因而可以利用它同步加大距离台站间的时钟漂移情况。本文基于噪声互相关方法,我们尝试运用该26s的脉动信号检测非洲、北美和欧洲等地区地震台站的时钟精度。结果发现TAM,OBN台站的时钟在2002~2009年间相对稳定;CCM台站的时钟在2006~2009年间出现了约1s偏差,并且时钟的漂移量不稳定;KOWA台站的时钟漂移从2012年10月的约150s最大上升至2013年1月的约500s。本文将得到的结果与Stehly等(2007)利用背景噪声方法得到的结果、以及远震P波初至到时残差进行了对比分析。利用本文提出的方法,通过与经精确校正过的陆地台站同步,可校正北大西洋海底地震仪的时钟。Yingjie Xia Sidao Ni Xiangfang Zeng Jun Xie Baoshan Wang Songyong Yuan 檀玉娟(译) 王宝善(校) 2017世界地震译丛2017,48,3:0
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