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Nutritional characteristics and fertilization of Chinese cabbage
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作者 景海春 王正祥 +2 位作者 周艺敏 兰耀龙 朱静华 《华北农学报》 CSCD 北大核心 1994年第S2期86-91,共6页
Nutritional accumulation mainly occurres from growth stage 2 to stage 3(lotus-setting stage to early heading stage, 48 - 72 days after transplanting)in Chinese cabbage. The uptake ratio of N and K is nearly l:l,and th... Nutritional accumulation mainly occurres from growth stage 2 to stage 3(lotus-setting stage to early heading stage, 48 - 72 days after transplanting)in Chinese cabbage. The uptake ratio of N and K is nearly l:l,and their uptake amounts are obviously higher than that of P. Balanced fertilization .especially the suitable combination of N and K,is important for the production of high yield and high quality. 展开更多
关键词 CHINESE CABBAGE NUTRITIONAL CHARACTERISTICS .fertilization
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The Role of Extracellular Ca^(2+) Influx,Intracellular Ca^(2+) Release and Calm odulin in MouseEgg Fertilization
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作者 SunQing-yuan TanJing-he 《Journal of Northeast Agricultural University(English Edition)》 CAS 1999年第2期152-157,共6页
The effects of various Ca 2+ modifying drugs on moue egg fertilization were studied.Ca 2+ chelator,ethylen glycol bis (2 aminoethyl) tetracetic acid(EGTA),and calmodulin (CaM) antagonist,trifluoperzaine... The effects of various Ca 2+ modifying drugs on moue egg fertilization were studied.Ca 2+ chelator,ethylen glycol bis (2 aminoethyl) tetracetic acid(EGTA),and calmodulin (CaM) antagonist,trifluoperzaine(TFP),inhibited fertilization in a dose dependent manner,whild Ca 2+ channel bolcker,verapamil,did not have any effect.When intracellular Ca 2+ release was blocked by 8 (N,N diethylamino) octy1 3,4, 5 trimethoxybenzonate(TMB 8) or the Ca 2+ oscillations were inhibited by an inhibitor of endoplasmic reticulum Ca 2+ ATPase,thapsigargin,the second polar body emission and pronuclear formation were significantly decreased.In contrast,inhibition of intracellular Ca 2+ release via bolckage of inositol 1,4,5 triphosphate (IP3) production by neomycin or lithium did not affect fertilization.The results sugest that both extracellular influx,intracellular Ca 2+ release and CaM activation are required for normal fertilization.However,extracellular influx through voltage gated Ca 2+ channel and intracellular release induced by IP3 are not the only pathways for producing Ca 2+ transients in moue eggs. 展开更多
关键词 calcium CALMODULIN fertilization mouse
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Response of Soybean(Glycine max)to Different Sources and Levels of Phosphours Fertilization
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作者 Owoade Folasade Mary Adegboyega Adewumi Oluwaponmile 《Journal of Northeast Agricultural University(English Edition)》 CAS 2017年第1期21-26,共6页
Phosphorus is crucial to crop growth and yield because of its multiple effects on plant nutrition. Most tropical soils have low plant available phosphorus and there is the need for external input of P to achieve optim... Phosphorus is crucial to crop growth and yield because of its multiple effects on plant nutrition. Most tropical soils have low plant available phosphorus and there is the need for external input of P to achieve optimum yield. The response of soybean to different sources and levels of phosphorus fertilization were therefore investigated between August, 2013 and January, 2014. The treatments consisted of four fertilizer sources [Sokoto Rock Phosphate (SRP), single super phosphate, Di-Ammonium Phosphate (DAP) and control] and five levels of fertilizers (0, 15, 30, 60 and 75 kg P· hm-2) fitted into Randomized Complete Block Design (RCBD) with three replications. Soil samples were collected, processed and analyzed before planting and after harvest. Data on growth (plants height, numbers of leaves, numbers of branches and numbers of flowers) and yield (pod and grain weights) were analyzed using ANOVA and significant means were separated using LSD at 5% probability level. Application of DAP at 15 kg P· hm2 and 30 kg P· hm2 produced the highest grain yield and showed significant differences in plant height, numbers of leaves and numbers of branches. SRP should not be recommended for the study area, because there was no significant difference across all the parameters and it was characterized with low grain yield, due to its level of acidity and the mildly acidic nature of the soil. 展开更多
关键词 PHOSPHORUS fertilization source soybean and response
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Function of RanGAP1 in Mouse Oocyte Fertilization
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作者 Hao Wei-jie Sun Lu-shuang +4 位作者 Hu Xiao-yang Xu Ying Ding Cong Yan Yun-qin Cao Yun-kao 《Journal of Northeast Agricultural University(English Edition)》 CAS 2018年第4期38-42,共5页
RanGAP1 is a Ran GTPase-activating protein that plays a pivotal role in the majority of nucleocytoplasmic transport pathways. The protein is limited to somatic cells. In this study, the localization and possible funct... RanGAP1 is a Ran GTPase-activating protein that plays a pivotal role in the majority of nucleocytoplasmic transport pathways. The protein is limited to somatic cells. In this study, the localization and possible functions of RanGAP1 were examined during mouse oocyte fertilization. Immunofluorescence analysis showed that after sperm penetration, RanGAP1 was found to diffuse within the cytoplasm, but concentrated in the microtuble of the reversed spindle and the constriction ring between the oocyte and the second polar body; with the expansion of sperm chromatin, RanGAP1 began to move to the region around the expanding sperm and oocyte chromatin, and gradually concentrated around the growing parents pronuclei. After the male and female pronuclei apposed, the membrane of one pronuclei broke first, numerous concentrated RanGAP1 dots were observed in the chromosome region. With the chromatin condensing into chromosome, the parents chromosomes mixed together and prepared to start the first mitosis, the condensed RanGAP1 was just the shape of the microtuble to assemble the first mitosis spindle. These showed that RanGAP1 played an important role in regulating spindle functions, chromosome alignment, PB2 extrusion and pronuclei nuclear envelope assembly/disassembly in mouse oocyte fertilization. 展开更多
关键词 RanGAP1 IMMUNOFLUORESCENCE nucleus assembly mouse oocyte fertilization
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Study on the Balanced Fertilization forCorn in Black SoilRegion
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作者 LiuDe-zhi GaoYun 《Journal of Northeast Agricultural University(English Edition)》 CAS 1999年第2期94-99,共6页
Regressive models were obtained by employing '311 B' and '3414' optimal regressive desingns through 5 year (1993~1997) field experiment,and by datum processing with computer.These models express the... Regressive models were obtained by employing '311 B' and '3414' optimal regressive desingns through 5 year (1993~1997) field experiment,and by datum processing with computer.These models express the relationships between corn yields in high,middle and low yield areas and N,P,and K application rates in black soil.By analysis to the models,the fertilizer application rates for maximum yield and optimal yield were achieved. 展开更多
关键词 black soil CORN study on balanced fertilization
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Key fungal communities related to alleviating replanting stress of Lanzhou lily under silicon fertilizer and microbial agents application
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作者 WANG Yi-qin YU Yan-lin +5 位作者 YANG Hong-yu LI Hui HOU Lei MAN Hua-li HAN Jia SHI Gui-ying 《植物营养与肥料学报》 北大核心 2025年第2期395-406,共12页
【Objectives】Si and microbial application could relieve the crop replanting problems(CRPs).We further studied the change of key microorganisms that are related to the beneficial effects,aiming at provide reference fo... 【Objectives】Si and microbial application could relieve the crop replanting problems(CRPs).We further studied the change of key microorganisms that are related to the beneficial effects,aiming at provide reference for the manufacture and application of both microbial agents and Si fertilizer in food lily production.【Methods】A field experiment was conducted over a three-year period,from March 2019 to March 2022.The experimental field had been continuously cultivated with lily for 9 years.Three treatments were established:silicon fertilizer(SF),microbial agents(“Special 8^(TM)”,MF),and combined application of silicon fertilizer and microbial agents(SMF).A control group with blank soil(CK)was also included.At seedling stage of Lanzhou lilies in 2020 and 2021,the shoot and bulb dry weight,and the plant height and stem diameter of Lanzhou lilies were investigated for calculation of seedling index.In July 2020,20 plants were selected in each plot,and root zone soils were sampled at a depth of 20 cm,10 cm away from the roots,and then mixed to form a composite sample.The soil available Si and organic matter content were analyzed,and the fungal community structure and some specific microbial groups in soils were determined with high-throughput sequencing of ITS.【Results】All the three treatments significantly enhanced the lily plant growth and the seedling index,compared to CK.Besides,SF and MF treatments increased the relative abundances(RA)and diversity of fungal communities,and altered the community structures.The RA of some specific groups were found to be significantly correlated with the seedling index and/or soil available Si.Of them,the RA of the genera Fusarium,Dactylonectria,Humicola,Stilbella,and the species Humicola_grisea showed a positive correlation,while that of the genera Mortierella,Stilbella,Holtermanniella,and the species Mortierella_fatshederae showed a negative correlation with seedling index.The genera Fusarium,Stilbella,the species Humicola_grisea,and Dactylonectria_estremocensis showed a positive correlation,while the genura Stilbella,and the species Mortierella fatshederae showed a negative correlation with available Si content.In the co-occurence network of top twenty fungal genera and top sixteen bacterial genera(RA>0.2%),Holtermanniella was the only genus that interacted with the bacteria and negatively correlated with bacterial genus Blastococcus.Holtermanniella was also the most densely connected genera,followed by the genus Fusarium,Didymella and Humicola.In addition,the genus Holtermanniella was the key species connecting fungal and bacterial community in soil.Fungal functional prediction revealed that SF,MF and SMF treatments decreased plant pathogens guilds and increased the beneficial guilds Ectomycorrhizal,plant saprophyte,leaf saprophyte,and arbuscular mycorrhizal compared to CK.【Conclusions】Combined application of silicon fertilizer and microbial agents can alleviate continuous replanting problems of Lanzhou lilies through restoring the fungal community diversity,and promoting plant residue depredation,thus reducing soil born disease incidence.The beneficial genus Humicola and its one species H.grisea acts as bioconversion,and the genus Acremonium acts as plant pathogen inhibitor. 展开更多
关键词 Lanzhou lily soil fungi diversity pathotroph saprophyte silicon fertilization microbial agent
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精子膜蛋白受精素(Fertilin)研究进展 被引量:1
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作者 李林林 马恒东 《畜禽业》 2006年第4期35-37,共3页
精子膜蛋白受精素(Fertilin)是参与精卵质膜间相互作用最有特征性的候选分子之一。受精素由α、β两个亚基组成,为精子表面的异二聚体跨膜糖蛋白。fertilin-α(Fα)、Fertilin-β(Fβ)可能在精子发生、精子成熟、精子获能及精卵结合和... 精子膜蛋白受精素(Fertilin)是参与精卵质膜间相互作用最有特征性的候选分子之一。受精素由α、β两个亚基组成,为精子表面的异二聚体跨膜糖蛋白。fertilin-α(Fα)、Fertilin-β(Fβ)可能在精子发生、精子成熟、精子获能及精卵结合和融合中发挥重要作用。 展开更多
关键词 受精素 受精精卵结合/融合
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Combined Application of Organic and Inorganic Fertilizers on Black Soil Fertility and Maize Yield 被引量:7
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作者 ZHAO Jinwei ZHOU Lianren 《Journal of Northeast Agricultural University(English Edition)》 CAS 2011年第2期24-29,共6页
By two years (2007-2008) located fertilizer experiment, the effect of long-term combined application of organic and inorganic fertilizers on black soil fertility and crop yield was investigated in Shuangcheng City, ... By two years (2007-2008) located fertilizer experiment, the effect of long-term combined application of organic and inorganic fertilizers on black soil fertility and crop yield was investigated in Shuangcheng City, Heilongjiang Province. The results showed that the combined application of organic and inorganic fertilizers could increase the organinc matter, alkaline nitrogen, available phosphorus and available potassium. At the same time, the increasing application of organic fertilizer could reduce the soil bulk density and improve the field moisture capacity. Field moisture capacity and organic matter of the combined application of high quantities of organic manure and inorganic fertilizers AtB5 treatment increased the fhstest, organic matter increased by 3.33 g. kg and field moisture capacity increased by 11.25% than the beginning of the experiment. Under the same fertilization, the combined application of organic and inorganic fertilizers' increasing production range was higher than the single chemical fertilizers' which was from 0.8% to 9.4%. The results showed that the combined application of organic and inorganic fertilizers could increase the nutrient contents of soil and also was the highest productivity contribution to black soil fertility. It was the best fertilization structure of increasing productivity level and improving the soil fertility. 展开更多
关键词 black soil combined application of organic and inorganic fertilizers soil fertility maize yield
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Effect of water and fertilizer coupling optimization test on water use efficiency of rice in black soil regions 被引量:4
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作者 LIN Yanyu ZHANG Zhongxue +1 位作者 XU Dan NIE Tangzhe 《排灌机械工程学报》 EI CSCD 北大核心 2016年第2期151-156,共6页
How to improve the water use efficiency of rice in black soil regions was studied. The black soil region in paddy fields was chosen as the research object. The research showed the fertilizer coupling mathematical mode... How to improve the water use efficiency of rice in black soil regions was studied. The black soil region in paddy fields was chosen as the research object. The research showed the fertilizer coupling mathematical model with N,P,K,irrigation water( W) and water use efficiency( WUE),which was set up under the condition of controlled irrigation with quadratic D- 416 optimized saturation design. The results show that the decending order of single factor' s influence on the WUE was N,K,P and W. All the interactions between N&P,N&K,N&W,K&P,P&W and K&W on the WUE were raised initially,and when reached a certain value,they began to decline. The decending order of each interaction on the WUE was K&P,K&W,N&K,N&P,P&W and N&W. When the WUE was targeted within 1. 8- 2. 5 kg / km^3,an optimized proportion plan was obtained in the 95% confidence interval,i. e. N 87. 76- 103. 32 kg / hm^2,K_2 O 52. 37- 66. 53 kg / hm^2 and P_2O_536. 80- 46. 71 kg / hm^2. Furthermore,the late tillering of the soil moisture content was 70. 07%- 72. 57% of the saturated moisture content. 展开更多
关键词 black soil RICE controlled irrigation water and fertilizer optimization plan WUE
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Short Term Influence of Organic and Inorganic Fertilizer on Soil Microbial Biomass and DNA in Summer and Spring 被引量:4
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作者 Khalil ur Rehman Zhang Ying +2 位作者 Shahla Andleeb Zhao Jiang Erinle Kehinda Olajide 《Journal of Northeast Agricultural University(English Edition)》 CAS 2016年第1期20-27,共8页
The present study was conducted to see the short term impact of organic and inorganic fertilizers on soil microbial biomass both in spring and summer. Also aimed to observe the correlation between soil microbial bioma... The present study was conducted to see the short term impact of organic and inorganic fertilizers on soil microbial biomass both in spring and summer. Also aimed to observe the correlation between soil microbial biomass and soil DNA. The study concluded that type of fertilizer might alter the soil microbial biomass and DNA contents. In soil treated with organic fertilizers resulted in higher concentrations of microbial biomass and DNA contents in summer as compared to spring dute to increase in temperature. Correspondingly, in case of inorganic fertilizer, concentrations of soil microbial biomass and DNA detected higher in summer instead of spring. The statistical correlation between soil microbial biomass, DNA and ODR in spring and summer along with organic and inorganic fertilizers were calculated highly significant (p〉0.01). This study demonstrated the impact of fertilizers and seasonal variations on soil microbial biomass and also revealed significant correlation between soil microbial biomass and soil DNA. 展开更多
关键词 soil microbial biomass CORRELATION soil DNA fertilIZER seasonal variation IMPACT
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In situ polymerization coating and characteristics of coated NPK compound fertilizer 被引量:4
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作者 WANG Zhenghui ZHU Boming 《Journal of Northeast Agricultural University(English Edition)》 CAS 2007年第2期148-152,共5页
Controlled release NPK compound fertilizers were prepared by means of in situ polymerization of monomers on the surface of fertilizer granules at room temperature. Methacrylate, α-methyl acrylic acid, and ethylene di... Controlled release NPK compound fertilizers were prepared by means of in situ polymerization of monomers on the surface of fertilizer granules at room temperature. Methacrylate, α-methyl acrylic acid, and ethylene dimethylacrylate were used as monomers, Dibenzoyl peroxide as initiator, and cobalt naphthenate, and triethyl amine as promoters. The structures of coating materials were characterized by IR spectra. The thermogravimetric analysis result indicated that the coating materials were of good thermal stability. The mean thickness of single coating measured with screw gauge was ca. 140 μm. The morphologies of uncoated and coated fertilizer granules analyzed by using scanning electron microscopy were changed from porosities and gullies to hills and plain. The release rate of coated compound fertilizers in water could be controlled by the hydrophicity and thickness of coating. The increase in coating hydrophicity caused the increase in release rate of fertilizer. The increase in thickness of coating slowed the release rate. 展开更多
关键词 in situ polymerization coated compound fertilizer controlled release
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Effects of Phosphate Fertilizer on Cold Tolerance and Its Related Physiological Parameters in Rice Under Low Temperature Stress 被引量:3
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作者 Hou Li-gang Chen Wen-fu +4 位作者 Zhao Guo-chen Ma Wei Qi Chun-yan Liu Liang Sun Hong-jiao 《Journal of Northeast Agricultural University(English Edition)》 CAS 2012年第4期1-10,共10页
The study was designated to explore the physiological mechanism of cold tolerance enhanced by phosphate in rice. An experiment was conducted to investigate the effects of different levels of phosphate fertilizer on co... The study was designated to explore the physiological mechanism of cold tolerance enhanced by phosphate in rice. An experiment was conducted to investigate the effects of different levels of phosphate fertilizer on cold tolerance and its related physiological parameters in rice seedings (chilling-sensitive cv. Changbai 9 and chilling-tolerant cv. Jijing 81) under low temperature stress. At the same time, the identification of cold tolerance was conducted. Compared with the normal temperature treatment, the relative chlorophyll content, photosynthesis rate, Fv/Fm and qP decreased and index of unsaturated fatty acid increased in rice under low temperature stress. The effect of chilling-sensitive cultivars was more than that of chilling-tolerant cultivars, more phosphorus fertilizer properly improved seedling quality of rice, slowed relative chlorophyll content dropping degree of rice seeding, increased photosynthesis rate, Fv/Fm, qP and index of unsaturated fatty acids, and enhanced the ability to chilling-tolerant cultivars under low temperature. The effect on chilling-tolerant cultivars was significantly higher than that on chilling sensitive cultivars by applying more phosphorus fertilizer. Phosphate regulated photosynthetic physiology and membrane fluidity to reduce injury by low temperature, and increasd the cold tolerance capacity of rice. 展开更多
关键词 low temperature stress phosphate fertilizer RICE cold tolerance physiological parameter
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Coupling Effect of Water and Fertilizer on Soybean Yield and Nutrient Absorption 被引量:2
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作者 HAO Li ZU Wei +2 位作者 SUN Cong-shu LEI Shu-xia LIU Li-jun 《Journal of Northeast Agricultural University(English Edition)》 CAS 2003年第2期105-114,共10页
Soybean cultivar Bei 92-28 was tested in this experiment in 2000 to study the coupling effect of water and ferilizer on soybean yield.The results showed that the effect of irrigation varied among the levels of fertili... Soybean cultivar Bei 92-28 was tested in this experiment in 2000 to study the coupling effect of water and ferilizer on soybean yield.The results showed that the effect of irrigation varied among the levels of fertilizer application,and vice versa;pods per plant,seeds per pod.and 100-seed weight had positive correlations with soybean yield,but the degrees of correlations of different treatments were various;LAI and dry matter accumulation could be significantly increased when watered and applied fertilizer with different levels,but high fertilizer application treatment didn't obtain the highest yield;watering could increase the absolute absorption amount of N,P,K in seeds,but the accumulation rates were various. 展开更多
关键词 coupling effect WATER fertilIZER soybean yield
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Active fraction combination from Liuwei Dihuang decoction(LW-AFC) ameliorates corticosterone-induced long-term potentiation impairment in mice in vivo 被引量:4
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作者 HUANG Yan LI Dong +3 位作者 CHENG Bin LIU Gang ZHANG Yong-xiang ZHOU Wen-xia 《中国药理学与毒理学杂志》 CAS 北大核心 2019年第6期436-437,共2页
Liuwei Dihuang decoction(LW), a classic formula in traditional Chinese medicine(TCM), has been used for nearly one thousand years for various diseases with characteristic features of kidney yin deficiency. LW consists... Liuwei Dihuang decoction(LW), a classic formula in traditional Chinese medicine(TCM), has been used for nearly one thousand years for various diseases with characteristic features of kidney yin deficiency. LW consists of 6herbs including Dihuang[prepared root of Rehmannia glutinosa(Gaertn) DC], Shanyao(rhizome of Dioscorea polystachya Turcz), Shanzhuyu(fruit of Cornus officinalis Siebold Zucc), Mudanpi(root bark of Paeonia × suffruticosa Andrews),Zexie(rhizome of Alisma plantago-aquatica L) and Fuling(scleorotia of Wolfiporia extensa(Peck) Ginns)LW-active fraction combination(LW-AFC) is extracted from LW, it is effective for the treatment of kidney yin deficiency in many animal models. There are 3 fractions in LW-AFC, a polysaccharide fraction(LWB-B), a glycoside fraction(LWD-b) and an oligosaccharide fraction(CA-30). Our previous results indicate that LW-AFC has similar pharmacological effects to LW, modulating the balance of the NIM network. LW-AFC has positive effects in many animal models of kidney deficiency or disturbance of the NIM network. LW-AFC could improve the cognitive ability in Alzheimer′s disease(AD) animal models(APP/PS1, SAMP8), where modulating immune function and balancing the NIM network may play an important role in its cognition improving effects. Our study also showed that LW-AFC had protective effects on stress-induced disturbances of the NIM network. However, the underlying mechanisms remain elusive and need further investigation. OBJECTIVE This study evaluated the effects of LW-AFC and the active fractions(polysaccharide, LWB-B;glycoside, LWD-b;oligosaccharide,CA-30) on corticosterone(Cort)-induced long-term potentiation(LTP) impairment in vivo. METHODS LTP was used to evaluate the synaptic plasticity. LW-AFC was orally administered for seven days. The active fractions were given by either chronic administration(ig, ip, 7 d) or single administration(icv, ig, ip). Cort was injected subcutaneously 1 h before the high-frequency stimulation(HFS) to induce LTP impairment. Moreover, in order to research on the possible effective pathways, an antibiotic cocktail and an immunosuppressant were also used. RESULTS Chronic administration(ig) of LW-AFC and its three active fractions could ameliorate Cort-induced LTP impairment. Single administration(icv, ig, ip) of any of the active fractions had no effect on Cort-induced LTP impairment, while chronic administration(ig, ip) of LWB-B or LWD-b showed positive effects against Cort. Interestingly, CA-30 only showed protective effects via ig administration,and there was little effect when CA-30 was administered ip In addition, when the intestinal microbiota was disrupted by application of the antibiotic cocktail, CA-30 showed little protective effects against Cort. The effects of LW-AFC were also abolished when the immune function was inhibited. In the hippocampal tissue, Cort treatment increased corticosterone and glutamate, and LW-AFC could inhibit the Cort-induced elevation of corticosterone and glutamate;there was little change in D-serine in Cort-treated animals, but LW-AFC could increase the D-serine levels. CONCLUSION LW-AFC and its three active fractions could ameliorate Cort-induced LTP impairment. Their protective effects are unlikely by a direct way, and immune modulation might be the common pathway. CA-30 could protect LTP from impairment via modulating the intestinal microbiota. Decreasing corticosterone and glutamate and increasing D-serine in the Cort-treated animals’ hippocampal tissue might be one of the mechanisms for the neural protective effects of LW-AFC. Further study is needed to understand the underlying mechanisms. 展开更多
关键词 LW-active fraction COMBINATION ACTIVE FRACTIONS CORTICOSTERONE long-term POTENTIATION SYNAPTIC plasticity stress
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Effects of nitrogen fertilizer on physiological property and yield of wheat at the different soil moisture 被引量:1
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作者 张景略 康玲玲 +1 位作者 魏义长 郑英 《华北农学报》 CSCD 北大核心 1993年第S2期92-97,共6页
The results of pot and pond trials are as follows.On equal amount of nitrogen(N)applied,the wheat nitrate reduction activity(NRA)and photosynthesis strength and other phy-siological properties are stronger and yields ... The results of pot and pond trials are as follows.On equal amount of nitrogen(N)applied,the wheat nitrate reduction activity(NRA)and photosynthesis strength and other phy-siological properties are stronger and yields are higher at normal soil moisture than those atdrought.At the same soil moisture,in a certain range of N applied,these properties of wheat in-crease with the increasing of N applied,but they descend when the amount of N applied exceedsa certain range. 展开更多
关键词 nitrogen fertilIZER soil moisture WHEAT YIELD PHYSIOLOGICAL property
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Assessment on soil fertility of Dongting Lake wetland area (China) based on GIS and fuzzy evaluation 被引量:7
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作者 李忠武 黄金权 +2 位作者 李裕元 郭旺 朱剑峰 《Journal of Central South University》 SCIE EI CAS 2011年第5期1465-1472,共8页
Using soil data of the Second National Field Survey,the soil fertility of wetland ecosystem of Dongting Lake was evaluated by using the technology of GIS and method of fuzzy evaluation.Integrated with the wetland actu... Using soil data of the Second National Field Survey,the soil fertility of wetland ecosystem of Dongting Lake was evaluated by using the technology of GIS and method of fuzzy evaluation.Integrated with the wetland actuality of Dongting Lake and particularity of paddy,seven factors (including soil organic matter,total nitrogen,total phosphorus,total potassium,available phosphorus,available potassium,and pH value),closely related with soil fertility,were chosen to establish the index system of synthetical evaluation.Based on the effect degree of each selected index on soil fertility,a judgment matrix was built,and the weight coefficient was determined by the method of correlation coefficient.Finally,under the support of the spatial analysis module of GIS (Geographic Information System),the spatial distribution properties of soil fertility in wetland ecosystem of Dongting Lake were studied.The results show that the soil fertility of Dongting Lake wetland ecosystem is not very good,and the area of type III and type IV achieves 69.8%.As a result,many countermeasures should be taken to improve the soil fertility.As for the spatial properties,the soil fertility level of central and west Dongting Lake is much higher than that of north and south part.The soil fertility of paddy field surpasses that of red soil,and the contents of soil organic matter and total nitrogen in paddy field are large. 展开更多
关键词 Dongting Lake WETLAND ECOSYSTEM soil fertility fuzzy evaluation geographic information system (GIS)
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Filtering of long-term dependent fractal noise in fiber optic gyroscope 被引量:5
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作者 Chunhong Hua Zhang Ren Minhu Zhang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第6期1041-1045,共5页
Stochastic noises of fiber optic gyroscope (FOG) mainly contain white noise and fractal noise whose long-term dependent component causes FOG a rather slow drift. In order to eliminate this component, a two-step filt... Stochastic noises of fiber optic gyroscope (FOG) mainly contain white noise and fractal noise whose long-term dependent component causes FOG a rather slow drift. In order to eliminate this component, a two-step filtering methodology is proposed. Firstly, fractional differencing (FD) method is introduced to trans-form fractal noise into fractional white noise based on the estima-tion of Hurst exponent for long-term dependent fractal process, which together with the existing white noise make up of a gener-alized white noise. Further, an improved denoising algorithm of wavelet maxima is developed to suppress the generalized white noise. Experimental results show that the basic noise terms of FOG greatly decrease, and especially the slow drift is restrained effectively. The proposed methodology provides a promising ap-proach for filtering long-term dependent fractal noise. 展开更多
关键词 fiber optic gyroscope (FOG) fractal noise long-term dependence fractional differencing wavelet denoising.
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Long-term settlement prediction of high-speed railway bridge pile foundation 被引量:4
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作者 杨奇 冷伍明 +4 位作者 张升 聂如松 魏丽敏 赵春彦 刘维正 《Journal of Central South University》 SCIE EI CAS 2014年第6期2415-2424,共10页
The process and characteristics of loading on high-speed railway bridge pile foundation were firstly obtained by means of field research and analysis,and the corresponding loading function was presented.One-dimensiona... The process and characteristics of loading on high-speed railway bridge pile foundation were firstly obtained by means of field research and analysis,and the corresponding loading function was presented.One-dimensional consolidation equation of elastic multilayered soils was then established with single drainage or double drainages under multilevel loading.Moreover,the formulas for calculating effective stress and settlement were derived from the Laplace numerical inversion transform.The three-dimensional composite analysis method of bridge pile group was improved,where the actual load conditions of pile foundation could be simulated,and the consolidation characteristics of soil layers beneath pile were also taken into account.Eventually,a corresponding program named LTPGS was developed to improve the calculation efficiency.The comparison between long-term settlement obtained from the proposed method and the in-situ measurements of pile foundation was illustrated,and a close agreement is obtained.The error between computed and measured results is less than 1 mm,and it gradually reduces with time.It is shown that the proposed method can effectively simulate the long-term settlement of pile foundation and program LTPGS can provide a reliable estimation. 展开更多
关键词 bridge pile foundation long-term settlement CONSOLIDATION Laplace numerical inversion transform multilevel loading multilayered soils
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Nitrogen and Phosphorus Loss Law and Emission Reduction Effects Under Water and Fertilizer Management Integrated Mode in Dike Paddy Field 被引量:2
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作者 GUO Longsheng ZHOU Guangtao GUO Zhongyuan 《Journal of Northeast Agricultural University(English Edition)》 CAS 2009年第4期31-37,共7页
To achieve the purpose of reducing farm non-point source pollution, we integrated site specific nitrogen management precise irrigation, controlled drainage, and wetland eco-repair system in dike area of Taihu basin. D... To achieve the purpose of reducing farm non-point source pollution, we integrated site specific nitrogen management precise irrigation, controlled drainage, and wetland eco-repair system in dike area of Taihu basin. During investigation, it had given prominence for the water and fertilizer coupling effects of precise irrigation and site specific nutrient management, the characteristics of integration on controlled irrigation, controlled drainage and wetland ecosystem non-point source pollution control. Then the water and fertilizer integrated management mode of paddy field was put forward in Taihu basin where the water production efficiency increased to 1.64 kg. m-3, water saved 37.8%, fertilizer use efficiency raised 15,4%, yield raised 10%, and N, P load decreased 26%-72%. The modern agricultural and farmland ecosystems that control and cut down the farm non-point source pollution came into being, which can be a reference by Taihu basin to control its agricultural non-point source pollution and eutrophicated water body. 展开更多
关键词 paddy field the integrated mode of water and fertilizer management non-point source pollution nitrogen and phosphorus loss
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Displacement behavior and mechanism of long-term water flooding in sandstone oil reservoirs 被引量:2
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作者 CAO Ren-yi DAI Zong +4 位作者 WANG Zhi-kai WANG Ya-hui JIANG Jun LI hai-long JIA Zhi-hao 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第3期834-847,共14页
Sandstone oil reservoirs with huge bottom water and high permeability are generally developed with high flow rate.After long-term water flooding(LTWF),the water flooding characteristics are quite different from that o... Sandstone oil reservoirs with huge bottom water and high permeability are generally developed with high flow rate.After long-term water flooding(LTWF),the water flooding characteristics are quite different from that of original reservoir.In this paper,the effects of the PV number,viscosity,and displacement rate during LTWF are studied through experiments.The mechanism is analyzed based on analysis of changes in oil composition,rock mineral composition and wettability.The oil-water relative permeability curves,oil recovery and wettability were obtained with new experiments methods,which avoids the oil metering error by measuring oil and water separately.The research indicates that when the viscosity increases,the water phase permeability decreases,the residual oil saturation increases,and the water content rate increases earlier.A higher water flooding rate results in a higher ultimate recovery.A higher asphaltene content results in a higher viscosity and more oil-wet reservoir conditions.After LTWF,the wettability tends to water-wet,which is more favorable for heavy oil recovery.Moreover,LTWF reduces the clay content,which creates a more water-wet surface and a larger reservoir pore throat environment.This research provides insightful characteristics of offshore sandstone oil reservoirs,which can be used to enhance oil recovery. 展开更多
关键词 long-term water flooding sandstone reservoir relative permeability curve WETTABILITY
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