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Low-protein diet supplemented with 1% L-glutamine improves growth performance, serum biochemistry, redox status, plasma amino acids, and alters fecal microbiota in weaned piglets

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Animal Nutrition 2024年第2期17卷 144-154页

作者： jun Li jun bai Ying Yang Zhenlong Wu State Key Laboratory of Animal Nutrition and Feeding Department of Companion Animal Science China Agricultural University

Glutamine, one of the most abundant amino acids in the body, has been shown to exert various beneficial effects in pigs. However, knowledge regarding the role of dietary glutamine in low-protein diet-fed piglets remains scarce. The present study aimed to investigate the effects of different levels of L-glutamine on growth performance, serum biochemistry parameters, redox status, amino acids, and fecal microbiota in low-protein diet-fed piglets. A total of 128 healthy crossbred piglets(Landrace × Yorkshire)were randomly allocated into 4 groups of 4 replicate pens, with 8 piglets per pen. Piglets in the 4 groups were fed with corn and soybean meal-based low-protein diets(crude protein level, 17%) that contained0%, 1%, 2%, and 3% L-glutamine, respectively, for 28 d. Pigs administered 1% L-glutamine had greater body weight on d 28 and average daily gain(ADG, P < 0.01), whereas a lower feed to gain ratio(F:G) from d 1to 28(P < 0.01), compared to the other three groups. Besides, lower body weight on d 14 and 28, ADG,average daily feed intake, and higher F:G from d 15 to 28 and d 1 to 28 were observed in response to 2%and 3% L-glutamine treatments than 0% and 1% L-glutamine treatments(P < 0.01). Moreover, 1% Lglutamine reduced serum glucose, malondialdehyde, hydrogen peroxide concentrations and inhibited aspartate aminotransferase, alanine aminotransferase, myeloperoxidase activities in low-protein diet-fed piglets on d 14, with concomitantly upregulated catalase, total superoxide dismutase activities and glutathione level(P < 0.05). However, dietary 3% L-glutamine enhanced blood urea nitrogen content in pigs on d 14(P < 0.05). Further investigation revealed that 1% L-glutamine upregulated the serum glutamine, lysine, methionine, tyrosine, and reduced plasma valine content(P < 0.05). Additionally, 1% Lglutamine upregulated the abundance of p＿75＿a5, Clostridium, Lactobacillus, Prevotellaceae＿Prevotella,and Gemmiger in the stool of piglets on d 14, with the Streptococcus lev

关键词： Glutamine Low protein diet Pig Redox status Amino acid Microbiota

Lotus"Domain Formation by the Hydrolysis Reaction of Phospholipase D to Phospholipid Monolayer

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Chinese Chemical Letters 2003年第11期14卷 1199-1202页

作者： Qiang HE jun bai LI International Joint Lab the Center for Molecule SciencesInstitute of Chemistry Chinese Academy of SciencesBeijing 100080

Hydrolysis reaction of L-a-dipalmitoylphosphatidylcholine (L-DPPC) monolayer with phospholipase D (PLD) has been investigated by Brewster angle microscopy (BAM) combined with the film balance. It has been found that the L-DPPC domains were changed into the 搇otus?structure by PLD. It suggests that the hydrolysis reaction is incomplete and the products together with the nonreacted materials undergo a molecular rearrangement at the interface.

关键词： Brewster angle microscopy phospholipase D hydrolysis phospholipid monolayer.

Determination of activity interaction parameters of Nb in Fe-C-Nb melts at 1873 K

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Journal of Iron and Steel Research International 2022年第3期29卷 403-407页

作者： Jie Zhang Da-ya Wang bai-jun Yan State Key Laboratory of Advanced Metallurgy Department of Physical Chemistry of MetallurgySchool of Metallurgical and Ecological EngineeringUniversity of Science and Technology BeijingBeijing100083China Sinosteel Maanshan General Institute of Mining Research Co. Ltd.Ma’anshan243000AnhuiChina

The interaction parameters of Nb in Fe-C-Nb melts at 1873 K were measured using the chemical equilibrium *** Fe-C melts were equilibrated with the CaO-MgO-Al_(2)O_(3)-NbO_(2) slags under a controlled oxygen potential for 24 *** addition to acting as the protective gas,argon was adopted to control the oxygen *** on the data obtained in the experiments,the activity interaction parameters were obtained by the multiple linear regression *** first-order interaction parameters e_(Nb)^(C)and e_(Nb)^(Nb)are determined to be−0.035 and−0.134,*** second-order interaction parameters r_(Nb)^(C),r_(Nb)^(Nb,C),and r_(Nb)……(Nb)are determined to be 0.011,−0.0063,and 0.0023,*** thermodynamic data obtained are more reliable than those in previous publications for the Fe-C-Nb system when the Nb content range was 0.92-4.62 wt.%.

关键词： Nb Fe-C-Nb melt Chemical equilibrium method First-order interaction parameter Second-order interaction parameter

Recognition of Biotin-functionalized Liposomes

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Chinese Chemical Letters 2003年第8期14卷 832-835页

作者： Hai Feng ZHU jun bai LI International Joint Lab The Center for Molecular ScienceInstitute of ChemistryChinese Academy of SciencesBeijing 100080

Functionalized liposomes were prepared by mixing the biotin in the lipid vesicle suspensions. The experiments through immersing streptavidin deposited mica into the biotin modified liposome solution testify the spec... 详细信息

关键词： Recognition liposome TEM AFM.

Comparison between TVDI and CWSI for drought monitoring in the Guanzhong Plain,China

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Journal of Integrative Agriculture 2017年第2期16卷 389-397页

作者： bai Jian-jun YU Yuan Liping Di College of Tourism and Environment Shaanxi Normal University Center for Spatial Information Science & Systems George Mason University

Temperature vegetation dryness index （TVDI） and crop water stress index （CWSI） are two commonly used remote sens- ing-based agricultural drought indicators. This study explored the applicability of monthly moderate resolution imaging spectroradiometer （MODIS） normalized difference vegetation index （NDVI） and land surface temperature （LST） data for agricultural drought monitoring in the Guanzhong Plain, China in 2003. The data were processed using TVDI, calculated by parameterizing the relationship between the MODIS NDVI and LST data. We compared the effectiveness of TVDI against CWSI, derived from the MOD16 products, for drought monitoring. In addition, the surface soil moisture and monthly pre- cipitation were collected and used for verification of the results. Results from the study showed that：（1） drought conditions measured by TVDI and CWSI had a number of similarities, which indicated that both CWSI and TVDI can be used for drought monitoring, although they had some discrepancies in the spatiotemporal characteristics of drought intensity of this region; and （2） both standardized precipitation index （SPI） and SM contents at the depth of 10 and 20 cm had better correlations to CWSI than to TVDI, indicating that there were more statistically significant relationships between CWSI and SPI/SM, and that CWSI is a more reliable indicator for assessing and monitoring droughts in this region.

关键词： remote sensing agricultural drought TVDI CWSI

The dynamic impact of income and income distribution on food consumption among adults in rural China

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Journal of Integrative Agriculture 2021年第1期20卷 330-342,I0001,I0002页

作者： LI Lei ZHAI Shi-xian bai jun-fei National Agricultural and Rural Development Research Institute China Agricultural UniversityBeijing 100083P.R.China Beijing Food Safety Policy&Strategy Research Base Beijing 100083P.R.China College of Economics and Management China Agricultural UniversityBeijing 100083P.R.China

Previous studies have demonstrated that income has a significant effect on food demand in rural China. However, little research has focused on the dynamic impact of income and income distribution on food demand in rural China. Using China Health and Nutrition Survey data, this study employs a consistent two-step quadratic almost ideal demand system model, with addressed problems of endogeneity of total expenditure and zero shares, to estimate the food demand elasticities among adults in rural areas with regard to the different income strata. The results show that changes in income and income strata have significant effects on food demand in rural areas. Except for grains, all other food groups, including vegetables, oils and fats, animal products, and other foods, have positive income elasticities, and the rise in the income strata will lead to declining income elasticities for grains, vegetables, oils and fats, and animal products. Based on the estimated income elasticities, the food consumption projections indicate that reducing income inequality in rural society can improve the living standard of low-income people in terms of nutrient intakes.

关键词： income redistribution food demand endogeneity censored demand system rural China

Food economics and policies: Challenges and approaches toward better nutrition and safer food in China

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Journal of Integrative Agriculture 2019年第8期18卷 1737-1739页

作者： bai jun-fei ZHU Chen Beijing Food Safety Policy & Strategy Research Base China Agricultural University

China has achieved unprecedented successes in feeding the 1.3 billion population in the past few decades. Per capita occupation of grain and milk increased from 316.6 and 1 kg in 1978 to 445.7 and 26.85 kg in 2016, respectively. Per capita meat occupation also reached 61.9 kg in 2016 from nearly nothing at the beginning of the reform and opening (NBSC 1979-2018). With these successes in agricultural production, the quality of food consum ption has also improved significantly.

关键词： Food economics Challenges and approaches safer food

Microstructure Characteristic and Phase Evolution of Refractory Siderite Ore during Sodium-carbonate-added Catalyzing Carbothermic Reduction

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Journal of Iron and Steel Research International 2016年第9期23卷 891-899页

作者： Shao-jun bai Meng WU Chao LU Shu-ming WEN State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization Kunming 650093Yunnan China Faculty of Land Resource Engineering Kunming University of Science and Technology Kunming 650093 Yunnan China

Thermodynamic analysis of refractory siderite ore during carbothermic reduction was conducted. Micro- structure characteristics and phase transformation of siderite ore during sodium-carbonate-added catalyzing carboth- ermic reduction were investigated. X-ray diffraction （XRD）, scanning electron microscopy and energy-dispersive analysis of X rays were used to characterize the reduced samples. Results indicate that the solid reaction between FeO and SiO2 is inevitable during carbothermic reduction and the formation of fayalite is the main hindrance to the rapid reduction of siderite. The phase transformation of present siderite ore can be described as： siderite-magnetite-metallic iron, complying with the formation of abundant fayalite. Improving the reduction temperature （-1050 -C ） and duration is helpful for the formation and aggregation of metallic iron. The iron particle size in the reduced ore was below 20 l-m, and fayalite was abundant in the absence of sodium carbonate. With 5% Na2CO3 addition, the iron particle size in the reduced ore was generally above 50μm, and the diffraction intensity associated with metallic iron in the XRD pattern increased. The Na2O formed from the dissociation of Na2 CO3 can catalyze the carbothermie reduction of the siderite. This catalytic activity may be mainly caused by an increase in the reducing reaction activity of FeO.

关键词： siderite ore microstructure characteristic phase evolution catalyzing carbothermie reduction

First-principle study on the surface atomic relaxation properties of sphalerite

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International Journal of Minerals,Metallurgy and Materials 2012年第9期19卷 775-781页

作者： Jian Liu Shu-ming Wen Yong-jun Xian Shao-jun bai Xiu-min Chen Faculty of Land Resource Engineering Kunming University of Science and Technology Kunming 650093 China National Engineering Laboratory of Vacuum Metallurgy Kunming University of Science and Technology Kunming 650093 China

The surface properties of sphalerite （ZnS） were theoretically investigated using first principle calculations based on the density functional theory （DFT）. DFT results indicate that both the （110） and the （220） surfaces of sphalerite undergo surface atom relaxation after geometry optimization, which results in a considerable distortion of the surface region. In the normal direction, i.e., perpendicular to the sur- face, S atoms in the first surface layer move outward from the bulk （dl）, whereas Zn atoms move toward the bulk （d2）, forming an S-enriched surface. The values of these displacements are 0.003 nm for dl and 0.021 nm for d2 on the （110） surface, and 0.002 nm for dl and 0.011 nm for d2 on the （220） surface. Such a relaxation process is visually interpreted through the qualitative analysis of molecular mechanics. X-ray photoelectron spectroscopic （XPS） analysis provides the evidence for the S-enriched surface. A polysulphide （S n^2- ） surface layer with a bind- ing energy of 163.21 eV is formed on the surface of sphalerite after its grinding under ambient atmosphere. This S-enriched surface and the S 2- surface layer have important influence on the flotation properties ofsphalerite. Keywords：

关键词： sphalerite surface relaxation density fimctional theory froth flotation