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Effects of intra-gastric beta-casomorphin-7 on somatostatin and gastrin gene expression in rat gastric mucosa

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World Journal of Gastroenterology 2007年第14期13卷 2094-2099页

作者： Ya-Feng Zong Wei-Hua Chen Yuan-shu zhang Si-xiang Zou Department of Animal Physiology and Biochemistry Nanjing Agricultural University Nanjing 210095 Jiangshu Province China

AIM： To investigate the in vivo effect of beta-casomorphin-7on the regulation of gastric somatostatin and gastrin messenger RNA in rat gastric mucosa.METHODS： Somatostatin and gastrin mRNA were quantified by RT-PCR and in situ hybridization （ISH）in 24 rats. The rats were divided into three treatment groups： basal diet ＋ physiological saline （n = 8）, basal diet ＋ beta-casomorphin-7 （7.5 × 10^-7 mol）（n = 8）,and basal diet ＋ poly-Gly-7 （containing equal mol of N with 7.5 × 10^-7 mol beta-casomorphin-7）（n = 8）.After oral administration for 30 days, rats were killed by exsanguinations.RESULTS： After intra-gastric administration of betacasomorphin-7 for 30 d, gastrin mRNA increased by 52.8% （P 〈 0.05, n = 8）, and somatostatin mRNA levels decreased by 30.7% compared with the controls （P 〈0.01, n = 8）. No significant differences in the expression of the two genes were observed in the poly-Gly-treated group, although gastrin mRNA expression was elevated by 35.6% as against the control group （P = 0.15, n =8）. The long-term oral administration of a casomorphin solution significantly decreased the even gray of D-cells,but did not lower the number of D-cells both in the antrum and fundus. Interestingly, the number of G-cells increased in the antrum and fundus, but its average density was augmented only in the antrum.CONCLUSION： Beta-casomorphin-7 is capable of modulating gene expression of the regulatory peptides from G and D cells. Data from in situ hybridization studies indicate that beta-casomorphin-7 affects gastrin gene expression indirectly by means of the paracrine action of somatostatin, and depends on its intrinsic molecular function.

关键词： Beta-casomorphin-7 Adult rat Somatostatin Gastrin Expression

Response of soil Olsen-P to P budget under different long-term fertilization treatments in a fluvo-aquic soil

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Journal of Integrative Agriculture 2019年第3期18卷 667-676页

作者： zhang Wei-wei ZHAN Xiao-ying zhang shu-xiang Khalid Hamdan Mohamed Ibrahima XU Ming-gang Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences College of Urban and Environmental Sciences Peking University

The concentration of soil Olsen-P is rapidly increasing in many parts of China, where P budget(P input minus P output) is the main factor influencing soil Olsen-P. Understanding the relationship between soil Olsen-P and P budget is useful in estimating soil Olsen-P content and conducting P management strategies. To address this, a long-term experiment(1991–2011) was performed on a fluvo-aquic soil in Beijing, China, where seven fertilization treatments were used to study the response of soil Olsen-P to P budget. The results showed that the relationship between the decrease in soil Olsen-P and P deficit could be simulated by a simple linear model. In treatments without P fertilization(CK, N, and NK), soil Olsen-P decreased by 2.4, 1.9, and 1.4 mg kg^(–1) for every 100 kg ha^(–1) of P deficit, respectively. Under conditions of P addition, the relationship between the increase in soil Olsen-P and P surplus could be divided into two stages. When P surplus was lower than the range of 729–884 kg ha^(–1), soil Olsen-P fluctuated over the course of the experimental period with chemical fertilizers(NP and NPK), and increased by 5.0 and 2.0 mg kg^(–1), respectively, when treated with chemical fertilizers combined with manure(NPKM and 1.5 NPKM) for every 100 kg ha^(–1) of P surplus. When P surplus was higher than the range of 729–884 kg ha^(–1), soil Olsen-P increased by 49.0 and 37.0 mg kg^(–1) in NPKM and 1.5 NPKM treatments, respectively, for every 100 kg ha^(–1) P surplus. The relationship between the increase in soil Olsen-P and P surplus could be simulated by two-segment linear models. The cumulative P budget at the turning point was defined as the "storage threshold" of a fluvo-aquic soil in Beijing, and the storage thresholds under NPKM and 1.5 NPKM were 729 and 884 kg ha^(–1)P for more adsorption sites. According to the critical soil P values(CPVs) and the relationship between soil Olsen-P and P budget, the quantity of P fertilizers for winter wheat could be increased

关键词： long-term fertilization fluvo-aquic soil Olsen-P P budget critical soil P value

Recovery and Leaching of ^(15)N-Labeled Coated Urea in a Lysimeter System in the North China Plain

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Pedosphere 2011年第6期21卷 763-772页

作者： LI Gui-Hua ZHAO Lin-Ping zhang shu-xiang Y. HOSEN K. YAGI Ministry of Agriculture Key Laboratory of Crop Nutrition and Fertilization Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences Beijing 100081 （China） Japan International Research Center for Agricultural Sciences 1-10hwashi Tsukuba Ibaraki 305-8686 （Japan） National Institute for Agro-Environmental Sciences 3-1-3 Kannondai Tsukuba 305-8604 （Japan）

The effectiveness of polyolefin-coated urea （Meister-5 and Meister-10; CU） in a wheat （Triticum aestivum L.）-maize （Zea mays L.） rotation system was studied in lysimeter plots located in the North China Plain for three consecutive maizewheat-maize cropping seasons. An isotopic method was used to compare the fate of CU to that of non-coated urea （NCU）, and N application rates of 0, 100, 150 and 225 kg N ha-1 were evaluated. The results showed that the nitrogen use efficiency （15NUE） of CU was 13.3%-21.4% greater than that of NCU for the first crop. Alternatively, when the difference method was applied （apparent NUE）, no significant variations were observed among treatments in all three seasons. Although inorganic N leached from the 1.3 m layer was less than 1% of the total applied N, unidentified losses of 15N （losses of 15N = 15N applied as fertilizer - 15N absorbed by crops - 15N remaining in the 0-0.2 m layer - 15N leached from the 1.3 m layer） in CU-treated plots were 24.2%-26.5% lower than those of NCU-treated plots. The nitrate concentration in the 0-1.3 m layer of CU plots at the end of the experiment was 53% lower than that of NCU-treated plots. Thus, CU increased crop N uptake from fertilizer and reduced unidentified losses of applied N, which can reduce the risk of groundwater pollution.

关键词： 15N fertilizer nitrogen use efficiency polyolefin-coated urea residual N wheat-maize rotation system

Effect of continuous negative pressure water supply on the growth, development and physiological mechanism of Capsicum annuum L.

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Journal of Integrative Agriculture 2017年第9期16卷 1978-1989页

作者： LI Di LONG Huai-yu zhang shu-xiang WU Xue-ping SHAO Hong-ying WANG Peng Agronomy College Heilongjiang Bayi Agricultural University Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences

Effects of continuous negative pressure water supply on water consumption, growth and development, as well as physiological mechanism and quality of Capsicum annuum L. were investigated in this paper. Meanwhile, the optimal negative pressure water supply conditions for growth of C. annuum L. were screened out to achieve the goals of water conservation, high yield and high quality, thus providing theoretical foundation for its field production. The pot experiment within the greenhouse was utilized; the continuous negative pressure water supply was adopted; the four treatments, artificial watering（CK）, –5 k Pa（T1）, –10 k Pa（T2）, and –15 k Pa（T3） were set; and the daily water consumption, yield, as well as the biomass, nitrate reductase, root activity, vitamin C, capsaicin, and nutrient uptakes of nitrogen（N）, phosphorus（P） and potassium（K） during various stages of its growth were determined. Compared with CK, when the water supply pressure was controlled at –5 to –15 k Pa in the experiment, the total water consumption of C. annuum L. reduced by 53.42 to 67.75%, the total water consumption intensity reduced by 54.29 to 67.14%, and the water use efficiency increased by 12.66 to 124.67%. The N accumulation in a single strain of C. annuum L. from the color turning stage to the red ripe stage increased by 15.99 to 100.55%, respectively, compared with that of CK; the P accumulation increased by 20.47 to 154.00% relative to that of CK, and the K accumulation increased by 64.92 to 144.9% compared with that of CK. Compared with CK, C. annuum L. yield was remarkably improved by 13.79% at T1, and contents of vitamin C, capsaicin as well as carotenoids at all growth stages were enhanced by 13.42–147.01%, 11.54–71.01%, and 41.1–568.06%, respectively. Nitrate reductase activity, root activity and chlorophyll（a＋b） were markedly increased by 335.78–500%, 79.6–140.68% and 114.95–676.19%, respectively, from immature stage to full ripe stage. Adopting the continuous negative pressure wa

关键词： negative pressure water supply Capsicum annuum L. physiological indexes yield quality

Effect of long-term fertilization on phosphorus fractions in different soil layers and their quantitative relationships with soil properties

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Journal of Integrative Agriculture 2022年第9期21卷 2720-2733页

作者： WANG Qiong QIN Zhen-han zhang Wei-wei CHEN Yan-hua ZHU Ping PENG Chang WANG Le zhang shu-xiang Gilles COLINET Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences/National Engineering Laboratory for Improving Quality of Arable LandBeijing 100081P.R.China TERRA Gembloux Agro-Bio TechUniversity of LiegeGembloux5030Belgium Institute of Plant Nutrition Resources and EnvironmentBeijing Academy of Agriculture and Forestry SciencesBeijing 100097P.R.China Agricultural Environment and Resources Center Jilin Academy of Agricultural SciencesChangchun 130033P.R.China

Investigating the dynamics and distribution of soil phosphorus(P) fractions can provide a basis for enhancing P utilization by crops. Four treatments from a 29-year long-term experiment in black soil with maize cropping were involved in this study: no fertilizer(CK), inorganic nitrogen and potassium(NK), inorganic nitrogen, phosphorus, and potassium(NPK), and NPK plus manure(NPKM). We analyzed soil P fractions in different soil layers using a modified Hedley sequential method. The long-term NPKM treatment significantly increased total P by 0.6–1.6 times in the different soil layers. The Olsen-P concentration far exceeded the environmental threshold for soil Olsen-P(50.6 mg kg) in the NPKM treatment in the 0–60 cm soil profile. Moreover, the concentrations and proportion of labile and partially labile inorganic P(Pi) fractions(i.e., Na HCO-extracted Pi, Na OH-extracted Pi, and dilute HClextracted Pi) to the sum of all P fractions(Pt) in the 0–60 cm soil profile were higher in the NPKM treatment than in the NPK treatment, indicating that manure could promote the transformation of non-labile into more labile forms of P in soil, possibly by manure reducing P fixation by soil particles. Soil organic matter, Mehlich-3 extractable iron(Fe), and organic-bound aluminum were increased by fertilization, and were the main factors influencing the differences in the P fractions in the 0–20 cm soil layer. Soil mineral components, i.e., free Fe oxide and Ca CO, were the main factors influencing the P fractions in the subsoil. The soil P transformation process varied with soil layer and fertilization. Application of manure fertilizer can increase the labile(Olsen) P concentrations of the various soil layers, and thus should reduce the mineral P fertilizer requirement for crop growth and reduce potential environmental damage.

关键词： long-term experiment phosphorus fractions soil profile phosphorus availability black soil

Characteristics of inorganic phosphorus fractions and their correlations with soil properties in three non-acidic soils

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Journal of Integrative Agriculture 2022年第12期21卷 3626-3636页

作者： zhang Nai-yu WANG Qiong ZHAN Xiao-ying WU Qi-hua HUANG Shao-min ZHU Ping YANG Xue-yun zhang shu-xiang Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences/National Engineering Laboratory for Improving Quality of Arable LandBeijing 100081P.R.China TERRA Gembloux Agro-Bio TechUniversity of LiegeGembloux 5030Belgium Institute of Environment and Sustainable Development in Agriculture Chinese Academy of Agricultural SciencesBeijing 100081P.R.China Institute of Bioengineering Guangdong Academy of Sciences/Guangdong Modern Agricultural Technology Research and Development CenterGuangzhou 510316P.R.China Institute of Plant Nutrient Agricultural Resources and Environmental SciencesHenan Academy of Agricultural SciencesZhengzhou 450002P.R.China Institute of Agricultural Resources and Environment Jilin Academy of Agricultural SciencesChangchun 130033P.R.China College of Natural Resources and Environment Northwest A&F UniversityYangling 712100P.R.China

Understanding the characteristics and influences of various factors on phosphorus(P)fractions is of significance for promoting the efficiency of soil *** on long-term experiments on black soil,fluvo-aquic soil,and loess soil,which belong to Phaeozems,Cambisols,and Anthrosols in the World Reference Base for Soil Resources(WRB),respectively,five fertilization practices were selected and divided into three groups:no P fertilizer(CK/NK),balanced fertilizer(NPK/NPKS),and manure plus mineral fertilizer(NPKM).Soil inorganic P(Pi)fractions and soil properties were analyzed to investigate the characteristics of the Pi fractions and the relationships between Pi fractions and various soil *** results showed that the proportion of Ca_(10)-P in the sum of total Pi fractions was the highest in the three soils,accounting for 33.5%in black soil,48.8%in fluvo-aquic soil,and 44.8%in loess ***-term fertilization practices resulted in periodic changes in soil Pi accumulation or *** black soil and fluvo-aquic soil,the Pi accumulation was higher in the late period(10–20 years)of fertilization than in the early period(0–10 years)under NPK/NPKS and NPKM,whereas the opposite result was found in loess *** Pi accumulation occurred in all Pi fractions in black soil;mainly in Ca_(8)-P,Fe-P,and Ca_(10)-P in fluvo-aquic soil;and in Ca_(2)-P,Ca_(8)-P,and O-P in loess *** CK/NK,the soil Pi was depleted mainly in the early period in each of the three *** addition to the labile Pi(Ca_(2)-P)and moderately labile Pi(Ca_(8)-P,Fe-P,Al-P),the Ca_(10)-P in black soil and fluvo-aquic soil and O-P in loess soil could also be used by *** analysis showed that soil properties explained more than 90%of the variation in the Pi fractions in each soil,and the explanatory percentages of soil organic matter(SOM)were 43.6%in black soil,74.6%in fluvo-aquic,and 38.2%in loess ***,decisions regarding the application of P fertilizer should consider

关键词： non-acidic soils long-term fertilization phosphorus fractions soil properties organic matter

Assessment of the contribution percentage of inherent soil productivity of cultivated land in China

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Journal of Integrative Agriculture 2019年第11期18卷 2619-2627页

作者： WANG Shi-chao WANG Jin-zhou ZHAO Ya-wen REN Yi XU Ming-gang zhang shu-xiang LU Chang-ai National Engineering Laboratory of Farmland Cultivation Technology/Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural SciencesBeijing 100081P.R.China The National Agro-Tech Extension and Service Center Beijing 100125P.R.China

The contribution percentage of inherent soil productivity(CPISP)refers to the ratio of crop yields under no-fertilization versus under conventional fertilization with the same field *** is a comprehensive measure of soil *** study used 1086 on-farm trials(from 1984-2013)and 27 long-term field experiments(from 1979-2013)to quantify changes in ***,we present CPISP3 values,which reflect the CPISP states during the first three years after site establishment,for a series of sites at different locations in China collected in 1984-1990(the 1980s),1996-2000(the 1990s),and 2004-2013(the 2000s).The results showed that the average CPISP3 value for three crops(wheat,rice,and maize)was 53.8%.Historically,the CPISP3 in the 1990s(57.5%)was much higher than those in the 1980s(50.3%),and the 2000s(52.0%)(P≤0.05).Long-term no-fertilization caused CPISP levels to gradually decline and then stabilize;for example,in a mono-cropping system with irrigation,the CPISP values in Northwest and Northeast China declined by 4.5 and 4.0%,respectively,each year for the first ten years,but subsequently,the CPISP values *** contrast,the CPISP for upland crops in double-cropping systems continued to decrease at a rate of 1.1%per *** CPISP for upland-paddy cropping decreased very slowly(0.07%per year),whereas the CPISP for paddy cropping decreased sharply(3.1%per year,on average)for the first two years and then remained steady during the following ***,upland crops in double-cropping systems consume the most inherent soil productivity,whereas paddy fields are favourable for maintaining a high level of ***,our results demonstrate a need to further improve China’s CPISP3 values to meet growing productivity demands.

关键词： crop yield inherent soil productivity typical cropping system planting years cropspecies

Low-complexity model predictive control of a four-level active neutral point clamped inverter without weighting factors

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Transportation Safety and Environment 2024年第2期6卷 96-103页

作者： Chaoqun xiang Ziyin Fan Songyang Jiang Xinan zhang shu Cheng School of Traffic and Transportation Engineering Central South UniversityChangsha 410075HunanChina CRRC Dalian Electric Traction R&D Center Co. LtdDalian 116200LiaoningChina School of Engineering The University of Western AustraliaPerthWA 6009Australia

The four-level active neutral point clamped(ANPC)inverter has become increasingly widely used in the renewable energy indus-try since it offers one more voltage level without increasing the total number of active switches compared to the three-level ANPC *** model predictive current control(MPCC)is a promising control method for multi-level ***,the conven-tional MPCC suffers from high computational complexity and tedious weighting factor tuning in multi-level inverter applications.A low-complexity MPCC without weighting factors for a four-level ANPC inverter is proposed in this *** computational burden and voltage vector candidate set are reduced according to the relationship between voltage vector and neutral point voltage *** proposed MPCC shows excellent steady-state and dynamics performances while ensuring the neutral point voltage *** efficacy of the proposed MPCC is verified by simulation and experimental results.

关键词： four-level active neutral point clamped(ANPC)inverter model predictive current control(MPCC) low complexity without weighting factors

Mg-Al-hydrotalcite with alkaline sites protects Ni/KIT-6 from formation of amorphous coke in glycerol steam reforming via tailoring reaction intermediates

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Frontiers of Chemical Science and Engineering 2024年第4期18卷 25-39页

作者： Yunyu Guo Yiran Wang Yuewen Shao shu zhang Yi Wang Song Hu Jun xiang Xun Hu School of Material Science and Engineering University of JinanJinan 250022China Joint International Research Laboratory of Biomass Energy and Materials College of Materials Science and EngineeringNanjing Forestry UniversityNanjing 210037China State Key Laboratory of Coal Combustion Huazhong University of Science and TechnologyWuhan 430074China

During steam reforming,the performance of a catalyst and amount/property of coke are closely related to reaction intermediates reaching surface of a ***,modification of reaction intermediates by placing Mg-Al-hydrotalcite above Ni/KIT-6 catalyst in steam reforming of glycerol was conducted at 300 to 600°*** results revealed that the catalytic activity of Ni/KIT-6 in the lower bed was enhanced with either Mg1-Al5-hydrotalcite(containing more acidic sites)or Mg5-Al1-hydrotalcite(containing more alkaline sites)as upper-layer *** in situ infrared characterization of steam reforming demonstrated that Mg-Al-hydrotalcite catalyzed the deoxygenation of glycerol,facilitating the reforming of the partially deoxygenated intermediates over Ni/***-Al-hydrotalcite as protective catalyst,however,did not protect the Ni/KIT-6 from formation of more ***,this did not lead to further deactivation of Ni/KIT-6 while Mg5-Al1-hydrotalcite even substantially enhanced the catalytic stability,even though the coke was much more significant than that in the use of single Ni/KIT-6(52.7%vs.28.6%).The reason beneath this was change of the property of coke from more aliphatic to more ***5-Al1-hydrotalcite catalyzed dehydration of glycerol,producing dominantly reaction intermediates bearing C=C,which formed the catalytic coke of with carbon nanotube as the main form with smooth outer walls as well as higher aromaticity,C/H ratio,crystallinity,crystal carbon size,thermal stability,and resistivity toward oxidation on Ni/KIT-6 in the lower *** comparison,the abundance of acidic sites on Mg1-Al5-hydrotalcite catalyzed the formation of more oxygen-containing species,leading to the formation of carbon nanotubes of rough surface on Ni/KIT-6.

关键词： steam reforming of glycerol Mg-Alhydrotalcite sacrificial catalyst reaction intermediates property of coke