Iron-sulfur clusters(ISC)are essential cofactors for proteins involved in various biological processes,such as electron transport,biosynthetic reactions,DNA repair,and gene expression regulation.ISC assembly protein I...Iron-sulfur clusters(ISC)are essential cofactors for proteins involved in various biological processes,such as electron transport,biosynthetic reactions,DNA repair,and gene expression regulation.ISC assembly protein IscA1(or MagR)is found within the mitochondria of most eukaryotes.Magnetoreceptor(MagR)is a highly conserved A-type iron and iron-sulfur cluster-binding protein,characterized by two distinct types of iron-sulfur clusters,[2Fe-2S]and[3Fe-4S],each conferring unique magnetic properties.MagR forms a rod-like polymer structure in complex with photoreceptive cryptochrome(Cry)and serves as a putative magnetoreceptor for retrieving geomagnetic information in animal navigation.Although the N-terminal sequences of MagR vary among species,their specific function remains unknown.In the present study,we found that the N-terminal sequences of pigeon MagR,previously thought to serve as a mitochondrial targeting signal(MTS),were not cleaved following mitochondrial entry but instead modulated the efficiency with which iron-sulfur clusters and irons are bound.Moreover,the N-terminal region of MagR was required for the formation of a stable MagR/Cry complex.Thus,the N-terminal sequences in pigeon MagR fulfil more important functional roles than just mitochondrial targeting.These results further extend our understanding of the function of MagR and provide new insights into the origin of magnetoreception from an evolutionary perspective.展开更多
Direct conversion of solar energy into chemical energy in an environmentally friendly manner is one of the most promising strategies to deal with the environmental pollution and energy crisis.Among a variety of materi...Direct conversion of solar energy into chemical energy in an environmentally friendly manner is one of the most promising strategies to deal with the environmental pollution and energy crisis.Among a variety of materials developed as photocatalysts,the core-shell metal/covalent-organic framework(MOF or COF)photocatalysts have garnered significant attention due to their highly porous structure and the adjustability in both structure and functionality.The existing reviews on core-shell organic framework photocatalytic materials have mainly focused on core-shell MOF materials.However,there is still a lack of indepth reviews specifically addressing the photocatalytic performance of core-shell COFs and MOFs@COFs.Simultaneously,there is an urgent need for a comprehensive review encompassing these three types of core-shell structures.Based on this,this review aims to provide a comprehensive understanding and useful guidelines for the exploration of suitable core-shell organic framework photocatalysts towards appropriate photocatalytic energy conversion and environmental governance.Firstly,the classification,synthesis,formation mechanisms,and reasonable regulation of core-shell organic framework were summarized.Then,the photocatalytic applications of these three kinds of core-shell structures in different areas,such as H_(2)evolution,CO_(2)reduction,and pollutants degradation are emphasized.Finally,the main challenges and development prospects of core-shell organic framework photocatalysts were introduced.This review aims to provide insights into the development of a novel generation of efficient and stable core-shell organic framework materials for energy conversion and environmental remediation.展开更多
Bismuth has garnered significant interest as an anode material for magnesium batteries(MBs) because of its high volumetric specific capacity and low working potential. Nonetheless, the limited cycling performance(≤10...Bismuth has garnered significant interest as an anode material for magnesium batteries(MBs) because of its high volumetric specific capacity and low working potential. Nonetheless, the limited cycling performance(≤100 cycles) limits the practical application of Bi as anode for MBs. Therefore, the improvement of Bi cycling performance is of great significance to the development of MBs and is also full of challenges. Here, Bi nanoparticles encapsulated in nitrogen-doped carbon with single-atom Bi embedded(Bi@NC) are prepared and reported as an anode material for MBs. Bi@NC demonstrates impressive performance, with a high discharge capacity of 347.5 mAh g^(-1) and good rate capability(206.4 mAh g^(-1)@500 mA g^(-1)) in a fluoride alkyl magnesium salt electrolyte. In addition, Bi@NC exhibits exceptional long-term stability, enduring 400 cycles at 500 mA g^(-1). To the best of our knowledge, among reported Bi and Bi-based compounds for MBs, Bi@NC exhibits the longest cycle life in this work. The magnesium storage mechanism of Bi@NC is deeply studied through X-ray diffraction, transmission electron microscopy and X-ray photoelectron spectroscopy. This work provides some guidance for further improving the cycling performance of other alloy anodes in MBs.展开更多
Under the background of global warming, extreme cold events occur frequently. It is important to enhance the understanding of cold air patterns for forecasting cold air and reducing cold air-induced meteorological dis...Under the background of global warming, extreme cold events occur frequently. It is important to enhance the understanding of cold air patterns for forecasting cold air and reducing cold air-induced meteorological disasters. The study used the daily minimum temperatures from the National Climate Centre to classify the cold events affecting China into five different grades and the characteristics of different intensity cold events in China during the winter from 1960 to 2020 were analyzed. The results showed that there is little difference in the distribution of the frequency of general cold events from north to south, with duration longer in the north than in the south and an increase in frequency in the north in the last 60 years. The frequency of strong cold events is more in the north of China than in the south of China, and the duration is longer in the south than in the north China, with the frequency decreasing in most parts of the country. In addition to latitude, cold events frequency is closely linked to topography, with basins surrounded by high mountains being difficult to be affected by cold events, especially extreme cold events. In terms of month distribution, December was subject to the highest frequency of cold events and the longest duration of a single cold events process.展开更多
Protein is quantitatively the most expensive nutrient in swine diets. Hence it is imperative to understand the physiological roles played by amino acids in growth, development, lactation, reproduction, and health of p...Protein is quantitatively the most expensive nutrient in swine diets. Hence it is imperative to understand the physiological roles played by amino acids in growth, development, lactation, reproduction, and health of pigs to improve their protein nutrition and reduce the costs of pork production. Due to incomplete knowledge of amino acid biochemistry and nutrition, it was traditionally assumed that neonatal, post-weaning, growing-finishing, and gestating pigs could synthesize sufficient amounts of all "nutritionally nonessential amino acids" (NEAA) to support maximum production performance. Therefore, over the past 50 years, much emphasis has been placed on dietary requirements of nutritionally essential amino acids as building blocks for tissue proteins. However, a large body of literature shows that NEAA, particularly glutamine, glutamate, arginine and proline regulate physiological functions via cell signaling pathways, such as mammalian target of rapamycin, AMP-activated protein kinase, extracellular signal-related kinase, Jun kinase, mitogen-activated protein kinase, and NEAA-derived gaseous molecules (e.g., nitric oxide, carbon monoxide, and hydrogen sulfide). Available evidence shows that under current feeding programs, only 70% and 55% of dietary amino acids are deposited as tissue proteins in 14-day-old sow-reared piglets and in 30-day-old pigs weaned at 21 days of age, respectively. Therefore, there is an urgent need to understand the robes and dietary requirements of NEAA in swine nutrition. This review highlights the basic biochemistry and physiology of absorption and utilization of amino acids in young pigs to enhance the efficacy of utilization of dietary protein and to minimize excretion of nitrogenous wastes from the body.展开更多
In the past two decades, a considerable amount of research has focused on the determination of the digestible(DE) and metabolizable energy(ME) contents of feed ingredients fed to swine. Compared with the DE and ME sys...In the past two decades, a considerable amount of research has focused on the determination of the digestible(DE) and metabolizable energy(ME) contents of feed ingredients fed to swine. Compared with the DE and ME systems, the net energy(NE) system is assumed to be the most accurate estimate of the energy actually available to the animal. However, published data pertaining to the measured NE content of ingredients fed to growing pigs are limited. Therefore, the Feed Data Group at the Ministry of Agricultural Feed Industry Centre(MAFIC) located at China Agricultural University has evaluated the NE content of many ingredients using indirect calorimetry. The present review summarizes the NE research works conducted at MAFIC and compares these results with those from other research groups on methodological aspect. These research projects mainly focus on estimating the energy requirements for maintenance and its impact on the determination, prediction, and validation of the NE content of several ingredients fed to swine. The estimation of maintenance energy is affected by methodology, growth stage,and previous feeding level. The fasting heat production method and the curvilinear regression method were used in MAFIC to estimate the NE requirement for maintenance. The NE contents of different feedstuffs were determined using indirect calorimetry through standard experimental procedure in MAFIC. Previously generated NE equations can also be used to predict NE in situations where calorimeters are not available. Although popular, the caloric efficiency is not a generally accepted method to validate the energy content of individual feedstuffs. In the future,more accurate and dynamic NE prediction equations aiming at specific ingredients should be established, and more practical validation approaches need to be developed.展开更多
Grain yield in cereal crops is a complex trait controlled by multiple genes and influenced by developmental processes and environment. Here we report the effects of alleles Rht8 and Ppd-D1 a on plant height, time to h...Grain yield in cereal crops is a complex trait controlled by multiple genes and influenced by developmental processes and environment. Here we report the effects of alleles Rht8 and Ppd-D1 a on plant height, time to heading, and grain yield and its component traits. Association analysis and quantitative trait locus mapping using phenotypic data from 15 environments led to the following conclusions. First, both Rht8 and Ppd-D1 a reduce plant height. However, Ppd-D1 a but not Rht8 causes earlier heading.Second, both Rht8 and Ppd-D1 a promote grain yield and affect component traits. Their combined effects are substantially larger than those conferred by either allele alone.Third, promotion of grain yield by Rht8 and Ppd-D1 a is through increasing fertile spikelet number. We speculate that Rht8 and Ppd-D1 a act independently and additively in control of plant height, grain yield and yield component. Combination of the two alleles is desirable for adjusting plant height and enhancing grain yield and abiotic stress tolerance.展开更多
Early colonization of intestinal microbiota during the neonatal stage plays an important role on the development of intestinal immune system and nutrients absorption of the host.Compared to the normal birth weight(NBW...Early colonization of intestinal microbiota during the neonatal stage plays an important role on the development of intestinal immune system and nutrients absorption of the host.Compared to the normal birth weight(NBW)piglets,intrauterine growth restricted(IUGR)piglets have a different intestinal microbiota during their early life,which is related to maternal imprinting on intestinal microbial succession during gestation,at birth and via suckling.Imbalanced allocation of limited nutrients among fetuses during gestation could be one of the main causes for impaired intestinal development and microbiota colonization in neonatal IUGR piglets.In this review,we summarized the potential impact of maternal imprinting on the colonization of the intestinal microbiota in IUGR piglets,including maternal undernutrition,imbalanced allocation of nutrients among fetuses,as well as vertical microbial transmission from mother to offspring during gestation and lactation.At the same time,we give information about the current maternal nutritional strategies(mainly breastfeeding,probiotics and prebiotics)to help colonization of the advantageous intestinal microbiota for IUGR piglets.展开更多
The objective of this study was to evaluate the effects of supplemental magnesium (Mg) on the performance of gilts and parity 3 sows and their piglets. Fifty-six grits (Trial 1) and 56 sows (Trial 2) were assign...The objective of this study was to evaluate the effects of supplemental magnesium (Mg) on the performance of gilts and parity 3 sows and their piglets. Fifty-six grits (Trial 1) and 56 sows (Trial 2) were assigned to one of 4 treatments according to their mating weight, respectively. The treatments comprised corn-soybean meal based gestation and lactation diets (0.21% magnesium) supplemented with 0, 0.015, 0.03, or 0.045% Mg from mating until weaning. The results showed that magnesium supplementation significantly (P 〈 0.05) reduced the weaning to estrus interval in both gilts and sows. There were significant effects (P 〈 0.05) of supplemental magnesium on the total number of piglets born, born alive and weaned in sows. In late gestation and lactation, the digestibility of crude fiber (quadratic effects, P 〈 0.05), and crude protein (P 〈 0.05), were significantly influenced by magnesium in gilts and sows, respectively. There were differences among the 4 groups in terms of the apparent digestibility of dry matter and crude fiber in sows (P 〈 0.0S) during both early and late gestation. The apparent digestibility of gross energy was increased for sows in late gestation (P 〈 0.05), and lactation (quadratic effects, P 〈 0.0S). At farrowing and weaning, serum prolactin levels and alkaline phosphate activities linearly increased in sows as the Mg supplementation increased (P 〈 0.0.5). Serum Mg of sows at farrowing and serum urea nitrogen of sows at weaning was significantly influenced by Mg supplementation (P 〈 0.05). The Mg concentration in sow colostrum and the serum of their piglets were increased by supplemental magnesium (P 〈 0.05). In addition, growth hormone levels were linearly elevated (P 〈 0.05) in the serum of piglets suckling sows. Our data demonstrated that supplemental magnesium has the potential to improve the reproduction performance of sows, and the suitable supplemental dose ranged from 0.015% to 0.03%.展开更多
Background: Postprandial nutrients utilization and metabolism of a certain diet is a complicated process. The metabolic feature of pigs after intake of corn-soybean meal or casein-starch diets are largely unknown. The...Background: Postprandial nutrients utilization and metabolism of a certain diet is a complicated process. The metabolic feature of pigs after intake of corn-soybean meal or casein-starch diets are largely unknown. Therefore,this study was conducted to investigate the dynamic postprandial changes of plasma metabolic profile using growing pigs using metabolomics.Methods: Twenty-four growing pigs with average initial body weight(BW) about 30 kg were placed in metabolic cages and then fitted with precaval vein catheters. Pigs were fed daily 4% of initial body weight. Two experimental diets were included:(i) a starch-casein based purified diet(PD) and(ii) a common corn-soybean meal diet(CD).Plasma was collected before feeding and 0.5 h, 1 h, 2 h, 4 h, 8 h after feeding.Results: In both diets, compared to prior to feeding, the concentrations of glucose, most amino acids, metabolites such as 5-aminopentanoic acid, pipecolic acid, ornithine and 5-hydroxy-L-tryptophan were significantly increased in plasma during the first hour, whereas the concentrations of plasma triglycerides, glutamate, glycine, palmitelaidic acid, 13-HODE and oleic acid were decreased in the first hour. Compared with PD group, concentration of plasma leucine and isoleucine declined at 30 min in CD group. Plasma linoleic acid, sphingosine and many dipeptides were significantly higher in pigs fed CD.Conclusion: Most significant metabolic changes occurred during the first hour after feeding and then became relatively stable after 2 h in both diets. These results show a broad scope picture of postprandial changes in plasma metabolites after intake of PD and CD and could be a reference for further nutrition intervention as well as the design of nutritional studies.展开更多
Background:Intrauterine growth restriction(IUGR)has negative impacts on the postnatal survival,growth and development of humans and animals,with not only on newborns but also adulthood.However,the characteristics for ...Background:Intrauterine growth restriction(IUGR)has negative impacts on the postnatal survival,growth and development of humans and animals,with not only on newborns but also adulthood.However,the characteristics for nutrient digestion and absorption in IUGR offspring are still largely unknown.Therefore,the normal birth weight(NBW)and IUGR growing pigs were used in this study to investigate their differences in nutrient utilization,with an expectition for further nutritional optimization of the IUGR offspring during their later life.Methods:Twelve IUGR and 12 NBW growing pigs were fitted with catheters in their portal vein to measure blood flow rate as well as nutrients and metabolites in plasma.The digestibilities of nutrients in different intestinal segments,and bacterial fermentation in the large intestine were examined to reveal the characteristics of nutrients utilization in IUGR versus NBW pigs.Results:The rate of portal venous blood flow did not differ beween IUGR and NBW pigs.Plasma concentrations of total cholesterol,triglycerides and glucose were much lower but those of urea were higher in the portal vein of IUGR pigs,compared with the NBW pigs.The ileal digestibility of dry matter,gross energy and starch were lower in IUGR pigs than in NBW pigs.IUGR increased hindgut microbial diversity and bacterial fermentation activity in the caecum.In vitro cross-fermentation of ileal digesta by caecal microbes of NBW and IUGR pigs showed that gas production was much higher for IUGR ileal digesta regardless of the source of caecal inocula.Conclusion:IUGR impairs the nutrient digestion and absorption in small intestine,reduces caecal microbial diversity and promotes bacterial fermentation in the large intestine during the growing phase.These findings aid in our understanding of nutrient metabolism in IUGR pigs and provide the basis for future nutritional interventions.展开更多
Background: Fasting is a simple metabolic strategy that is used to estimate the maintenance energy requirement where the energy supply for basic physiological functions is provided by the mobilization of body reserves...Background: Fasting is a simple metabolic strategy that is used to estimate the maintenance energy requirement where the energy supply for basic physiological functions is provided by the mobilization of body reserves.However, the underlying metabolic components of maintenance energy expenditure are not clear. This study investigated the differences in heat production(HP), respiratory quotient(RQ) and plasma metabolites in pigs in the fed and fasted state, using the techniques of indirect calorimetry and metabolomics.Methods: Nine barrows(45.2 ± 1.7 kg BW) were fed corn-soybean based meal diets and were kept in metabolism crates for a period of 14 d. After 7 d adaptation, pigs were transferred to respiratory chambers to determine HP and RQ based on indirect calorimetry. Pigs were fed the diet at 2,400 k J ME/(kg BW0.6·d) during d 8 to 12. The last 2 d were divided into 24 h fasting and 48 h fasting treatment, respectively. Plasma samples of each pig were collected from the anterior vena cava during the last 3 d(1 d while pigs were fed and 2 d during which they were fasted).The metabolites of plasma were determined by high-resolution mass spectrometry using a metabolomics approach.Results: Indirect calorimetry analysis revealed that HP and RQ were no significant difference between 24 h fasting and 48 h fasting, which were lower than those of fed state(P < 0.01). The nitrogen concentration of urine tended to decrease with fasting(P = 0.054). Metabolomics analysis between the fed and fasted state revealed differences in15 compounds, most of which were not significantly different between 24 h fasting and 48 h fasting. Identified compounds were enriched in metabolic pathways related to linoleic acid metabolism, amino acid metabolism,sphingolipid metabolism, and pantothenate and Co A biosynthesis.Conclusion: These results suggest that the decreases in HP and RQ of growing pigs under fasting conditions were associated with the alterations of linoleic acid metabolism and amino acid metabolism. The integrative analysis also revealed that growing pigs under a 24-h fasting were more appropriate than a 48-h fasting to investigate the metabolic components of maintenance energy expenditure.展开更多
By the field experiment,we set up the treatments of non-application of potash fertilizer,conventional fertilization,balanced fertilization and halved application of potash fertilizer,and studied the effect of differen...By the field experiment,we set up the treatments of non-application of potash fertilizer,conventional fertilization,balanced fertilization and halved application of potash fertilizer,and studied the effect of different treatments on rice yield and soil nutrient content. The results showed that compared with non-application of potash fertilizer,conventional fertilization and balanced fertilization significantly increased the spike length,thousand kernel weight,yield and total potassium content of the stalk,as well as soil organic matter,total nitrogen and available phosphorus content; compared with conventional fertilization,the balanced fertilization did not significantly increase the rice growth and yield,but effectively increased rice grain total nitrogen,stalk total nitrogen and total phosphorus content,as well as soil available phosphorus and available potassium content. It could be found that potash fertilizer played a certain role in increasing rice yield and soil nutrient content,and the balanced fertilization had the most significant effect.展开更多
A water-soluble polysaccharide (OJP2) obtained from the roots of Ophiopogon japonicas, was precipitated with 95% ethanol and purified by DEAE-52 cellulose anion-exchange and Sephadex G-100 gel filtration chromatograph...A water-soluble polysaccharide (OJP2) obtained from the roots of Ophiopogon japonicas, was precipitated with 95% ethanol and purified by DEAE-52 cellulose anion-exchange and Sephadex G-100 gel filtration chromatography. The characteristics of OJP2 were determined by chemical analysis, high performance gel permeation chromatography (HPGPC), and gas chromatography-mass spectrometry (GC-MS). The results showed that the average molecular weight (Mw) of OJP2 was 35.2 kDa, and five kinds of monosaccharides including rhamnose, arabinose, xylose, glucose and galactose in a molar ratio of 0.5:5:4:1:10. Furthermore, the antioxidant activity of OJP2 was evaluated in H2O2-treated HaCaT cells and glucose-treated LO2 cells. The results show that OJP2 can increase the activity of SOD and NO production, and decrease the level of MDA in these two kinds of injury cells. OJP2 should be explored as a novel and potential natural antioxidant agent for use in functional foods or medicine.展开更多
Background: Dietary fiber can be fermented in gut of pigs and the end products of fermentation were short-chain fatty acids(SCFA). The SCFA had positive effects on gut bacteria and host immune system. In addition, SCF...Background: Dietary fiber can be fermented in gut of pigs and the end products of fermentation were short-chain fatty acids(SCFA). The SCFA had positive effects on gut bacteria and host immune system. In addition, SCFA can provide a part of available energy for pigs. However, there were limited reports on the relationship between dietary fiber, gut bacteria, and energy metabolism. Therefore, this study investigated how dietary fiber and enzyme addition impacted energy metabolism by acting on the microbial community and SCFA.Methods: Wheat bran(WB) was added to the corn-soybean meal-based diet at the levels of 12% and 27%, and oat bran(OB) at 15% and 36%. One of each diet was supplemented with or without 5000 U/kg feed of xylanase, so a total of 10 diets were allotted to 60 growing pigs(initial body weight: 27.2 ± 1.2 kg) using a randomized complete block design. The experiment was conducted in 10 consecutive periods using 6 similar open-circuit respiration chambers. Each pig was used for one 20-day period. During each period, six pigs were allowed 14 d to adapt to the diets in metabolic cages followed by 6 d(from d 15 to d 20) in respiration chambers to measure heat production(HP).Results: Pigs fed 36% OB diets had greater(P < 0.05) nutrient digestibility and net energy(NE) values compared to those fed 27% WB diets. Apparent digestibility coefficients of dry matter(DM) and crude protein(CP) were lower(P < 0.05) in pigs fed 27% WB diets compared with those fed 12% WB diets. Enzyme addition improved(P < 0.05)the NE values(11.37 vs. 12.43 MJ/kg DM) in diets with 27% WB. Supplementation of xylanase did not affect NE values for basal diets, OB diets and 12%WB diets. Compared with diets with 36% OB, pigs fed 27% WB-based diets excreted more total SCFA, acetate and propionate(expressed as g/kg feed DM) in fecal samples of pigs(P < 0.05).Pigs in the WB diets had greater proportion of phylum Bacteroidetes while phylum Firmicutes were greater in pigs fed OB diets(P < 0.05). Pigs fed WB diets had greater(P < 0.05) abundance of Succinivibrio and Prevotella, which were associated with fiber degradation and SCFA production.Conclusion: Our results indicated diets supplied by high level of OB or WB promote the growth of fiber-degrading bacteria. The differences in fiber composition between WB and OB led to differences in nutrient digestibility and bacterial communities, which were ultimately reflected in energy metabolism. Enzyme supplementation improved nutrient digestibility as well as NE values for 27% WB diets but not for other diets, which indicated that effects of enzyme were related to type and level of dietary fiber in diets.展开更多
Health is maintained by a state of dynamic homeostasis in which nutrient intake and ex- penditure are of good balance. Therefore, it is important to know exactly the nutritional value of food sources, as well as the n...Health is maintained by a state of dynamic homeostasis in which nutrient intake and ex- penditure are of good balance. Therefore, it is important to know exactly the nutritional value of food sources, as well as the nutritional requirements of individuals, in order to achieve optimal nutrition. Considering the interaction between diet and individual back- ground, nutritional evaluation and recommendation has become a complicate issue needing further investigations. While traditional nutrition research has made significant progress in population nutrition, modern nutrition research is now becoming possible to focus on personalized nutrition in health promotion, disease prevention, performance improvement, and risk assessment of individual with the development of emerging omics technologies. This review tried to summarize the methods used in nutritional evaluation and recom- mendation as well as their applications. Though personal nutrition evaluation and recommendation are still not well-established, utilization of these advanced technologies may expand our knowledge in bioavailability and bioefficacy of diet ingredients, pathophysiological changes in response to dietary intervention, as well as nutrition-associated disease biomarkers discovery, and thus contributing to personalized nutrition.展开更多
Pollution flashover accidents occur frequently in railway OCS in saline-alkali areas.To accurately predict the pollution flashover voltage of insulators,a pollution flashover warning should be made in advance.Accordin...Pollution flashover accidents occur frequently in railway OCS in saline-alkali areas.To accurately predict the pollution flashover voltage of insulators,a pollution flashover warning should be made in advance.According to the operating environment of insulators along the Qinghai-Tibet railway,the pollution flashover experiments were designed for the cantilever composite insulator FQBG-25/12.Through the experiments,the flashover voltage under the influence of soluble contaminant density(SCD)of different pollution components,non-soluble deposit density(NSDD),temperature(T),and atmospheric pressure(P)was obtained.On this basis,the GA-BP neural network prediction model was established.P,SCD,NSDD,CaSO_(4) mass fraction(w(CaSO_(4))),and T were taken as input parameters,50%flashover voltage(U_(50%))of the insulator was taken as output parameters.The results showed that the prediction deviation was less than 10%,which meets the basic engineering requirements.The results could not only provide early warning for the anti-pollution flashover work of the railway power supply department,but also be used as an auxiliary contrast to verify the accuracy of the results of the experiments,and provide a theoretical basis for the classification of pollution levels in different regions.展开更多
In order to screen and identify excellent breeding resources and provide basic materials for Brassica rapa breeding,the contents of erucic acid,oleic acid and glucosinolate in 84 kinds of B. rapa were determined by ne...In order to screen and identify excellent breeding resources and provide basic materials for Brassica rapa breeding,the contents of erucic acid,oleic acid and glucosinolate in 84 kinds of B. rapa were determined by near-infrared spectroscopy,and the correlations among them were also analyzed. The results showed that the content of erucic acid and oleic acid were significantly negatively correlated,the contents of erucic acid and glucosinolate were significantly positively correlated,while the contents of oleic acid and glucosinolate were significantly negatively correlated; principal component analysis( PCA) were performed on the population materials,factors 1 and 2 were extracted for plotting,factor 1 and factor 2 could explain 73. 7% and 23. 2% of the phenotypic variation,respectively; through cluster analysis,79 materials aggregated to form group I,and five special variants deviated from the population. The variation of erucic acid,oleic acid and glucosinolates in B. rapa populations was rich and there was significant correlation. Through cluster analysis,five excellent B. rapa breeding materials( No. 32,No. 45,No. 46,No. 50,and No. 59) were screened.展开更多
Low-fishmeal and protein-saving diets are two prominent nutritional strategies utilized to address challenges related to the scarcity and sustainability of protein sources in aquaculture.However,these diets have been ...Low-fishmeal and protein-saving diets are two prominent nutritional strategies utilized to address challenges related to the scarcity and sustainability of protein sources in aquaculture.However,these diets have been associated with adverse effects on the growth performance,feed utilization,and disease resistance of aquatic animals.To mitigate these challenges,exogenous protease has been applied to enhance the quality of diets with lower protein contents or fishmeal alternatives,thereby improving the bioavailability of nutritional ingredients.Additionally,protease preparations were also used to enzymatically hydrolyze fishmeal alternatives,thus enhancing their nutritional utilization.The present review aims to consolidate recent research progress on the use of protease in aquaculture and conclude the benefits and limitations of its application,thereby providing a comprehensive understanding of the subject and identifying opportunities for future research.展开更多
Caries is one of the most prevalent human diseases,resulting from demineralization of tooth hard tissue caused by acids produced from bacteria,and can progress to pulpal inflammation.Filling restoration with dental re...Caries is one of the most prevalent human diseases,resulting from demineralization of tooth hard tissue caused by acids produced from bacteria,and can progress to pulpal inflammation.Filling restoration with dental resin composites(DRCs)is currently the most common treatment for caries.However,existing DRCs suffer from low fracture strength and lack comprehensive anti-caries bioactivity including remineralization,pulp protection,and anti-cariogenic bacteria effects.In this study,inspired by plant roots’ability to stabilize and improve soil,fluorinated urchin-like hydroxyapatite(FUHA)with a three-dimensional whisker structure and bioactive components of calcium,phosphorus,and fluorine was designed and synthesized by a dynamic self-assembly method.Furthermore,versatile FUHA particles with different loading fractions were used as functional fillers to fabricate methacrylate-based DRCs,where the urchin-like hydroxyapatite(UHA)filled DRCs and commercial DRCs(Z350XT and BEAUTIFIL II)served as the control groups.The results demonstrated that FUHA with 50 wt%loading in resin matrix endowed DRC(F5)with excellent physicochemical properties,dentin remineralization property,cell viability,promotion of dental pulp stem cells mineralization,and antibacterial properties.Meanwhile,F5 also presented good clinical handling and aesthetic characteristics.Therefore,structure/functional-integrated FUHA filled DRCs have potential as a promising strategy for tooth restoration and anti-caries bioactivity.展开更多
基金supported by the National Natural Science Foundation of China(31640001 and T2350005 to C.X.,U21A20148 to X.Z.and C.X.)Ministry of Science and Technology of China(2021ZD0140300 to C.X.)+2 种基金Natural Science Foundation of Hainan Province(No.822RC703 for J.L.)Foundation of Hainan Educational Committee(No.Hnky2022-27 for J.L.)Presidential Foundation of Hefei Institutes of Physical Science,Chinese Academy of Sciences(Y96XC11131,E26CCG27,and E26CCD15 to C.X.,E36CWGBR24B and E36CZG14132 to T.C.)。
文摘Iron-sulfur clusters(ISC)are essential cofactors for proteins involved in various biological processes,such as electron transport,biosynthetic reactions,DNA repair,and gene expression regulation.ISC assembly protein IscA1(or MagR)is found within the mitochondria of most eukaryotes.Magnetoreceptor(MagR)is a highly conserved A-type iron and iron-sulfur cluster-binding protein,characterized by two distinct types of iron-sulfur clusters,[2Fe-2S]and[3Fe-4S],each conferring unique magnetic properties.MagR forms a rod-like polymer structure in complex with photoreceptive cryptochrome(Cry)and serves as a putative magnetoreceptor for retrieving geomagnetic information in animal navigation.Although the N-terminal sequences of MagR vary among species,their specific function remains unknown.In the present study,we found that the N-terminal sequences of pigeon MagR,previously thought to serve as a mitochondrial targeting signal(MTS),were not cleaved following mitochondrial entry but instead modulated the efficiency with which iron-sulfur clusters and irons are bound.Moreover,the N-terminal region of MagR was required for the formation of a stable MagR/Cry complex.Thus,the N-terminal sequences in pigeon MagR fulfil more important functional roles than just mitochondrial targeting.These results further extend our understanding of the function of MagR and provide new insights into the origin of magnetoreception from an evolutionary perspective.
基金supported by the National Natural Science Foundation of China(52161145409,21976116)SAFEA of China("Belt and Road”Innovative Talent Exchange Foreign Expert Project#2023041004L)(High-end Foreign Expert Project#G2023041021L)the Alexander-von-Humboldt Foundation of Germany(GroupLinkage Program)。
文摘Direct conversion of solar energy into chemical energy in an environmentally friendly manner is one of the most promising strategies to deal with the environmental pollution and energy crisis.Among a variety of materials developed as photocatalysts,the core-shell metal/covalent-organic framework(MOF or COF)photocatalysts have garnered significant attention due to their highly porous structure and the adjustability in both structure and functionality.The existing reviews on core-shell organic framework photocatalytic materials have mainly focused on core-shell MOF materials.However,there is still a lack of indepth reviews specifically addressing the photocatalytic performance of core-shell COFs and MOFs@COFs.Simultaneously,there is an urgent need for a comprehensive review encompassing these three types of core-shell structures.Based on this,this review aims to provide a comprehensive understanding and useful guidelines for the exploration of suitable core-shell organic framework photocatalysts towards appropriate photocatalytic energy conversion and environmental governance.Firstly,the classification,synthesis,formation mechanisms,and reasonable regulation of core-shell organic framework were summarized.Then,the photocatalytic applications of these three kinds of core-shell structures in different areas,such as H_(2)evolution,CO_(2)reduction,and pollutants degradation are emphasized.Finally,the main challenges and development prospects of core-shell organic framework photocatalysts were introduced.This review aims to provide insights into the development of a novel generation of efficient and stable core-shell organic framework materials for energy conversion and environmental remediation.
基金supported by the National Natural Science Foundation of China (51972259,52127816,and 52202290)the National Key Research and Development Program of China (2020YFA0715000)+1 种基金the Natural Science Foundation of Hubei Province (2022CFA087)the funding support from China Scholarship Council/University College London for the joint Ph.D.scholarship (CXXM2110070005)。
文摘Bismuth has garnered significant interest as an anode material for magnesium batteries(MBs) because of its high volumetric specific capacity and low working potential. Nonetheless, the limited cycling performance(≤100 cycles) limits the practical application of Bi as anode for MBs. Therefore, the improvement of Bi cycling performance is of great significance to the development of MBs and is also full of challenges. Here, Bi nanoparticles encapsulated in nitrogen-doped carbon with single-atom Bi embedded(Bi@NC) are prepared and reported as an anode material for MBs. Bi@NC demonstrates impressive performance, with a high discharge capacity of 347.5 mAh g^(-1) and good rate capability(206.4 mAh g^(-1)@500 mA g^(-1)) in a fluoride alkyl magnesium salt electrolyte. In addition, Bi@NC exhibits exceptional long-term stability, enduring 400 cycles at 500 mA g^(-1). To the best of our knowledge, among reported Bi and Bi-based compounds for MBs, Bi@NC exhibits the longest cycle life in this work. The magnesium storage mechanism of Bi@NC is deeply studied through X-ray diffraction, transmission electron microscopy and X-ray photoelectron spectroscopy. This work provides some guidance for further improving the cycling performance of other alloy anodes in MBs.
文摘Under the background of global warming, extreme cold events occur frequently. It is important to enhance the understanding of cold air patterns for forecasting cold air and reducing cold air-induced meteorological disasters. The study used the daily minimum temperatures from the National Climate Centre to classify the cold events affecting China into five different grades and the characteristics of different intensity cold events in China during the winter from 1960 to 2020 were analyzed. The results showed that there is little difference in the distribution of the frequency of general cold events from north to south, with duration longer in the north than in the south and an increase in frequency in the north in the last 60 years. The frequency of strong cold events is more in the north of China than in the south of China, and the duration is longer in the south than in the north China, with the frequency decreasing in most parts of the country. In addition to latitude, cold events frequency is closely linked to topography, with basins surrounded by high mountains being difficult to be affected by cold events, especially extreme cold events. In terms of month distribution, December was subject to the highest frequency of cold events and the longest duration of a single cold events process.
基金supported by National Research Initiative Competitive Grants from the Animal Reproduction Program(2008-35203-19120)Animal Growth&Nutrient Utilization Program(2008-35206-18764)of the USDA National Institute of Food and Agriculture+6 种基金AHA(10GRNT4480020)Texas A&M AgriLife Research(H-8200)the National Basic Research Program of China(2013CB127302)the National Natural Science Foundation of China(30810103902,30972156,31172217,31272450,and 31272451)China Postdoctoral Science Foundation(2012T50163)Chinese Universities Scientific Funds(2012RC024)the Thousand-People Talent program at China Agricultural University
文摘Protein is quantitatively the most expensive nutrient in swine diets. Hence it is imperative to understand the physiological roles played by amino acids in growth, development, lactation, reproduction, and health of pigs to improve their protein nutrition and reduce the costs of pork production. Due to incomplete knowledge of amino acid biochemistry and nutrition, it was traditionally assumed that neonatal, post-weaning, growing-finishing, and gestating pigs could synthesize sufficient amounts of all "nutritionally nonessential amino acids" (NEAA) to support maximum production performance. Therefore, over the past 50 years, much emphasis has been placed on dietary requirements of nutritionally essential amino acids as building blocks for tissue proteins. However, a large body of literature shows that NEAA, particularly glutamine, glutamate, arginine and proline regulate physiological functions via cell signaling pathways, such as mammalian target of rapamycin, AMP-activated protein kinase, extracellular signal-related kinase, Jun kinase, mitogen-activated protein kinase, and NEAA-derived gaseous molecules (e.g., nitric oxide, carbon monoxide, and hydrogen sulfide). Available evidence shows that under current feeding programs, only 70% and 55% of dietary amino acids are deposited as tissue proteins in 14-day-old sow-reared piglets and in 30-day-old pigs weaned at 21 days of age, respectively. Therefore, there is an urgent need to understand the robes and dietary requirements of NEAA in swine nutrition. This review highlights the basic biochemistry and physiology of absorption and utilization of amino acids in young pigs to enhance the efficacy of utilization of dietary protein and to minimize excretion of nitrogenous wastes from the body.
基金financially supported by the Modern Agricultural Industry Technology System(CARS-36)Developing key equipment for digital management and monitoring environment in animal production(2013AA10230602)+2 种基金National Natural Science Foundation of China(31372317)the 111 Project(B16044)China Postdoctoral Science Foundation
文摘In the past two decades, a considerable amount of research has focused on the determination of the digestible(DE) and metabolizable energy(ME) contents of feed ingredients fed to swine. Compared with the DE and ME systems, the net energy(NE) system is assumed to be the most accurate estimate of the energy actually available to the animal. However, published data pertaining to the measured NE content of ingredients fed to growing pigs are limited. Therefore, the Feed Data Group at the Ministry of Agricultural Feed Industry Centre(MAFIC) located at China Agricultural University has evaluated the NE content of many ingredients using indirect calorimetry. The present review summarizes the NE research works conducted at MAFIC and compares these results with those from other research groups on methodological aspect. These research projects mainly focus on estimating the energy requirements for maintenance and its impact on the determination, prediction, and validation of the NE content of several ingredients fed to swine. The estimation of maintenance energy is affected by methodology, growth stage,and previous feeding level. The fasting heat production method and the curvilinear regression method were used in MAFIC to estimate the NE requirement for maintenance. The NE contents of different feedstuffs were determined using indirect calorimetry through standard experimental procedure in MAFIC. Previously generated NE equations can also be used to predict NE in situations where calorimeters are not available. Although popular, the caloric efficiency is not a generally accepted method to validate the energy content of individual feedstuffs. In the future,more accurate and dynamic NE prediction equations aiming at specific ingredients should be established, and more practical validation approaches need to be developed.
基金supported by the Ministry of Science and Technology of China (2017YFD0101000)Science and Technology Service Network Program (STS Program) of Chinese Academy of Sciences (KFJ-STS-ZDTP-024)National Natural Science Foundation of China (31371611)
文摘Grain yield in cereal crops is a complex trait controlled by multiple genes and influenced by developmental processes and environment. Here we report the effects of alleles Rht8 and Ppd-D1 a on plant height, time to heading, and grain yield and its component traits. Association analysis and quantitative trait locus mapping using phenotypic data from 15 environments led to the following conclusions. First, both Rht8 and Ppd-D1 a reduce plant height. However, Ppd-D1 a but not Rht8 causes earlier heading.Second, both Rht8 and Ppd-D1 a promote grain yield and affect component traits. Their combined effects are substantially larger than those conferred by either allele alone.Third, promotion of grain yield by Rht8 and Ppd-D1 a is through increasing fertile spikelet number. We speculate that Rht8 and Ppd-D1 a act independently and additively in control of plant height, grain yield and yield component. Combination of the two alleles is desirable for adjusting plant height and enhancing grain yield and abiotic stress tolerance.
基金supported by the Beijing Municipal Natural Science Foundation(S170001)the National Natural Science Foundation of China(31630074,31272449 and 31902170)+2 种基金the National Key Research and Development Program of China(2016YFD0500506 and 2018YDF0501002)the 111 Project(B16044)the Jinxinnong Animal Science Developmental Foundation.
文摘Early colonization of intestinal microbiota during the neonatal stage plays an important role on the development of intestinal immune system and nutrients absorption of the host.Compared to the normal birth weight(NBW)piglets,intrauterine growth restricted(IUGR)piglets have a different intestinal microbiota during their early life,which is related to maternal imprinting on intestinal microbial succession during gestation,at birth and via suckling.Imbalanced allocation of limited nutrients among fetuses during gestation could be one of the main causes for impaired intestinal development and microbiota colonization in neonatal IUGR piglets.In this review,we summarized the potential impact of maternal imprinting on the colonization of the intestinal microbiota in IUGR piglets,including maternal undernutrition,imbalanced allocation of nutrients among fetuses,as well as vertical microbial transmission from mother to offspring during gestation and lactation.At the same time,we give information about the current maternal nutritional strategies(mainly breastfeeding,probiotics and prebiotics)to help colonization of the advantageous intestinal microbiota for IUGR piglets.
基金The financial support from the Chinese Universities Scientific Fund(No.15059102, 2014JD017,2012QJ102,2012QJ105)National "Twelfth Five-Year" Science& Technology Pillar Program(No.2011BAD26B02)National Department Public Benefit Research Foundation(201403047)
文摘The objective of this study was to evaluate the effects of supplemental magnesium (Mg) on the performance of gilts and parity 3 sows and their piglets. Fifty-six grits (Trial 1) and 56 sows (Trial 2) were assigned to one of 4 treatments according to their mating weight, respectively. The treatments comprised corn-soybean meal based gestation and lactation diets (0.21% magnesium) supplemented with 0, 0.015, 0.03, or 0.045% Mg from mating until weaning. The results showed that magnesium supplementation significantly (P 〈 0.05) reduced the weaning to estrus interval in both gilts and sows. There were significant effects (P 〈 0.05) of supplemental magnesium on the total number of piglets born, born alive and weaned in sows. In late gestation and lactation, the digestibility of crude fiber (quadratic effects, P 〈 0.05), and crude protein (P 〈 0.05), were significantly influenced by magnesium in gilts and sows, respectively. There were differences among the 4 groups in terms of the apparent digestibility of dry matter and crude fiber in sows (P 〈 0.0S) during both early and late gestation. The apparent digestibility of gross energy was increased for sows in late gestation (P 〈 0.05), and lactation (quadratic effects, P 〈 0.0S). At farrowing and weaning, serum prolactin levels and alkaline phosphate activities linearly increased in sows as the Mg supplementation increased (P 〈 0.0.5). Serum Mg of sows at farrowing and serum urea nitrogen of sows at weaning was significantly influenced by Mg supplementation (P 〈 0.05). The Mg concentration in sow colostrum and the serum of their piglets were increased by supplemental magnesium (P 〈 0.05). In addition, growth hormone levels were linearly elevated (P 〈 0.05) in the serum of piglets suckling sows. Our data demonstrated that supplemental magnesium has the potential to improve the reproduction performance of sows, and the suitable supplemental dose ranged from 0.015% to 0.03%.
基金financially supported by the National Natural Science Foundation of China(31630074)the National Key Research and Development Program of China(2016YFD0500506 and 2018YFD0501002)+3 种基金the Beijing Municipal Natural Science Foundation(S170001)China Agriculture Research System(CARS-35)the “111” Project(B16044)Jinxinnong Animal Science Developmental Foundation
文摘Background: Postprandial nutrients utilization and metabolism of a certain diet is a complicated process. The metabolic feature of pigs after intake of corn-soybean meal or casein-starch diets are largely unknown. Therefore,this study was conducted to investigate the dynamic postprandial changes of plasma metabolic profile using growing pigs using metabolomics.Methods: Twenty-four growing pigs with average initial body weight(BW) about 30 kg were placed in metabolic cages and then fitted with precaval vein catheters. Pigs were fed daily 4% of initial body weight. Two experimental diets were included:(i) a starch-casein based purified diet(PD) and(ii) a common corn-soybean meal diet(CD).Plasma was collected before feeding and 0.5 h, 1 h, 2 h, 4 h, 8 h after feeding.Results: In both diets, compared to prior to feeding, the concentrations of glucose, most amino acids, metabolites such as 5-aminopentanoic acid, pipecolic acid, ornithine and 5-hydroxy-L-tryptophan were significantly increased in plasma during the first hour, whereas the concentrations of plasma triglycerides, glutamate, glycine, palmitelaidic acid, 13-HODE and oleic acid were decreased in the first hour. Compared with PD group, concentration of plasma leucine and isoleucine declined at 30 min in CD group. Plasma linoleic acid, sphingosine and many dipeptides were significantly higher in pigs fed CD.Conclusion: Most significant metabolic changes occurred during the first hour after feeding and then became relatively stable after 2 h in both diets. These results show a broad scope picture of postprandial changes in plasma metabolites after intake of PD and CD and could be a reference for further nutrition intervention as well as the design of nutritional studies.
基金supported by the National Natural Science Foundation of China(31630074,31422052,31972596,31902189,31902170)the Beijing Municipal Natural Science Foundation(S170001)+2 种基金the China Agriculture Research System(CARS-35),the 111 Project(B16044)the Jinxinnong Animal Science Developmental Foundation,State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products(2018KLGM03)China Postdoctoral Science Foundation(2018 M630235)。
文摘Background:Intrauterine growth restriction(IUGR)has negative impacts on the postnatal survival,growth and development of humans and animals,with not only on newborns but also adulthood.However,the characteristics for nutrient digestion and absorption in IUGR offspring are still largely unknown.Therefore,the normal birth weight(NBW)and IUGR growing pigs were used in this study to investigate their differences in nutrient utilization,with an expectition for further nutritional optimization of the IUGR offspring during their later life.Methods:Twelve IUGR and 12 NBW growing pigs were fitted with catheters in their portal vein to measure blood flow rate as well as nutrients and metabolites in plasma.The digestibilities of nutrients in different intestinal segments,and bacterial fermentation in the large intestine were examined to reveal the characteristics of nutrients utilization in IUGR versus NBW pigs.Results:The rate of portal venous blood flow did not differ beween IUGR and NBW pigs.Plasma concentrations of total cholesterol,triglycerides and glucose were much lower but those of urea were higher in the portal vein of IUGR pigs,compared with the NBW pigs.The ileal digestibility of dry matter,gross energy and starch were lower in IUGR pigs than in NBW pigs.IUGR increased hindgut microbial diversity and bacterial fermentation activity in the caecum.In vitro cross-fermentation of ileal digesta by caecal microbes of NBW and IUGR pigs showed that gas production was much higher for IUGR ileal digesta regardless of the source of caecal inocula.Conclusion:IUGR impairs the nutrient digestion and absorption in small intestine,reduces caecal microbial diversity and promotes bacterial fermentation in the large intestine during the growing phase.These findings aid in our understanding of nutrient metabolism in IUGR pigs and provide the basis for future nutritional interventions.
基金financially supported by the National Natural Science Foundation of China(31372317)Developing Key Equipment for Digital Management and Monitoring Environment in Animal Production(2013AA10230602)+1 种基金Prevention and Control of Nutritional Metabolism and Toxic Diseases in Livestock and Poultry(2016YFD0501204)the 111 Project(B16044)
文摘Background: Fasting is a simple metabolic strategy that is used to estimate the maintenance energy requirement where the energy supply for basic physiological functions is provided by the mobilization of body reserves.However, the underlying metabolic components of maintenance energy expenditure are not clear. This study investigated the differences in heat production(HP), respiratory quotient(RQ) and plasma metabolites in pigs in the fed and fasted state, using the techniques of indirect calorimetry and metabolomics.Methods: Nine barrows(45.2 ± 1.7 kg BW) were fed corn-soybean based meal diets and were kept in metabolism crates for a period of 14 d. After 7 d adaptation, pigs were transferred to respiratory chambers to determine HP and RQ based on indirect calorimetry. Pigs were fed the diet at 2,400 k J ME/(kg BW0.6·d) during d 8 to 12. The last 2 d were divided into 24 h fasting and 48 h fasting treatment, respectively. Plasma samples of each pig were collected from the anterior vena cava during the last 3 d(1 d while pigs were fed and 2 d during which they were fasted).The metabolites of plasma were determined by high-resolution mass spectrometry using a metabolomics approach.Results: Indirect calorimetry analysis revealed that HP and RQ were no significant difference between 24 h fasting and 48 h fasting, which were lower than those of fed state(P < 0.01). The nitrogen concentration of urine tended to decrease with fasting(P = 0.054). Metabolomics analysis between the fed and fasted state revealed differences in15 compounds, most of which were not significantly different between 24 h fasting and 48 h fasting. Identified compounds were enriched in metabolic pathways related to linoleic acid metabolism, amino acid metabolism,sphingolipid metabolism, and pantothenate and Co A biosynthesis.Conclusion: These results suggest that the decreases in HP and RQ of growing pigs under fasting conditions were associated with the alterations of linoleic acid metabolism and amino acid metabolism. The integrative analysis also revealed that growing pigs under a 24-h fasting were more appropriate than a 48-h fasting to investigate the metabolic components of maintenance energy expenditure.
基金Supported by Open Fund of Key Laboratory of Zhejiang Subtropical Soil and Plant NutritionZhejiang"SanNongLiuFang"Scientific and Technological Cooperation Project in 2016
文摘By the field experiment,we set up the treatments of non-application of potash fertilizer,conventional fertilization,balanced fertilization and halved application of potash fertilizer,and studied the effect of different treatments on rice yield and soil nutrient content. The results showed that compared with non-application of potash fertilizer,conventional fertilization and balanced fertilization significantly increased the spike length,thousand kernel weight,yield and total potassium content of the stalk,as well as soil organic matter,total nitrogen and available phosphorus content; compared with conventional fertilization,the balanced fertilization did not significantly increase the rice growth and yield,but effectively increased rice grain total nitrogen,stalk total nitrogen and total phosphorus content,as well as soil available phosphorus and available potassium content. It could be found that potash fertilizer played a certain role in increasing rice yield and soil nutrient content,and the balanced fertilization had the most significant effect.
文摘A water-soluble polysaccharide (OJP2) obtained from the roots of Ophiopogon japonicas, was precipitated with 95% ethanol and purified by DEAE-52 cellulose anion-exchange and Sephadex G-100 gel filtration chromatography. The characteristics of OJP2 were determined by chemical analysis, high performance gel permeation chromatography (HPGPC), and gas chromatography-mass spectrometry (GC-MS). The results showed that the average molecular weight (Mw) of OJP2 was 35.2 kDa, and five kinds of monosaccharides including rhamnose, arabinose, xylose, glucose and galactose in a molar ratio of 0.5:5:4:1:10. Furthermore, the antioxidant activity of OJP2 was evaluated in H2O2-treated HaCaT cells and glucose-treated LO2 cells. The results show that OJP2 can increase the activity of SOD and NO production, and decrease the level of MDA in these two kinds of injury cells. OJP2 should be explored as a novel and potential natural antioxidant agent for use in functional foods or medicine.
基金financially supported by the National Key Research and Development Program of China (2018YFD0500405)National Natural Science Foundation of China (31630074)+1 种基金National Natural Science Foundation of China (U1604106)the 111 Project (B16044)。
文摘Background: Dietary fiber can be fermented in gut of pigs and the end products of fermentation were short-chain fatty acids(SCFA). The SCFA had positive effects on gut bacteria and host immune system. In addition, SCFA can provide a part of available energy for pigs. However, there were limited reports on the relationship between dietary fiber, gut bacteria, and energy metabolism. Therefore, this study investigated how dietary fiber and enzyme addition impacted energy metabolism by acting on the microbial community and SCFA.Methods: Wheat bran(WB) was added to the corn-soybean meal-based diet at the levels of 12% and 27%, and oat bran(OB) at 15% and 36%. One of each diet was supplemented with or without 5000 U/kg feed of xylanase, so a total of 10 diets were allotted to 60 growing pigs(initial body weight: 27.2 ± 1.2 kg) using a randomized complete block design. The experiment was conducted in 10 consecutive periods using 6 similar open-circuit respiration chambers. Each pig was used for one 20-day period. During each period, six pigs were allowed 14 d to adapt to the diets in metabolic cages followed by 6 d(from d 15 to d 20) in respiration chambers to measure heat production(HP).Results: Pigs fed 36% OB diets had greater(P < 0.05) nutrient digestibility and net energy(NE) values compared to those fed 27% WB diets. Apparent digestibility coefficients of dry matter(DM) and crude protein(CP) were lower(P < 0.05) in pigs fed 27% WB diets compared with those fed 12% WB diets. Enzyme addition improved(P < 0.05)the NE values(11.37 vs. 12.43 MJ/kg DM) in diets with 27% WB. Supplementation of xylanase did not affect NE values for basal diets, OB diets and 12%WB diets. Compared with diets with 36% OB, pigs fed 27% WB-based diets excreted more total SCFA, acetate and propionate(expressed as g/kg feed DM) in fecal samples of pigs(P < 0.05).Pigs in the WB diets had greater proportion of phylum Bacteroidetes while phylum Firmicutes were greater in pigs fed OB diets(P < 0.05). Pigs fed WB diets had greater(P < 0.05) abundance of Succinivibrio and Prevotella, which were associated with fiber degradation and SCFA production.Conclusion: Our results indicated diets supplied by high level of OB or WB promote the growth of fiber-degrading bacteria. The differences in fiber composition between WB and OB led to differences in nutrient digestibility and bacterial communities, which were ultimately reflected in energy metabolism. Enzyme supplementation improved nutrient digestibility as well as NE values for 27% WB diets but not for other diets, which indicated that effects of enzyme were related to type and level of dietary fiber in diets.
基金supported by the Beijing Excellent Talent Support Program(PYZZ090428001238)the National Natural Science Foundation of China(No.30828024,30972156)+1 种基金State Key Laboratory of Animal Nutrition(2004DA125184Team0815)SpecialPublic Sector Fund in Agriculture(200903006)
文摘Health is maintained by a state of dynamic homeostasis in which nutrient intake and ex- penditure are of good balance. Therefore, it is important to know exactly the nutritional value of food sources, as well as the nutritional requirements of individuals, in order to achieve optimal nutrition. Considering the interaction between diet and individual back- ground, nutritional evaluation and recommendation has become a complicate issue needing further investigations. While traditional nutrition research has made significant progress in population nutrition, modern nutrition research is now becoming possible to focus on personalized nutrition in health promotion, disease prevention, performance improvement, and risk assessment of individual with the development of emerging omics technologies. This review tried to summarize the methods used in nutritional evaluation and recom- mendation as well as their applications. Though personal nutrition evaluation and recommendation are still not well-established, utilization of these advanced technologies may expand our knowledge in bioavailability and bioefficacy of diet ingredients, pathophysiological changes in response to dietary intervention, as well as nutrition-associated disease biomarkers discovery, and thus contributing to personalized nutrition.
基金Supported by the National Natural Science Foundation of China(51767014)the Scientific and Technological Research and Development Program of the China Railway(2017J010-C/2017).
文摘Pollution flashover accidents occur frequently in railway OCS in saline-alkali areas.To accurately predict the pollution flashover voltage of insulators,a pollution flashover warning should be made in advance.According to the operating environment of insulators along the Qinghai-Tibet railway,the pollution flashover experiments were designed for the cantilever composite insulator FQBG-25/12.Through the experiments,the flashover voltage under the influence of soluble contaminant density(SCD)of different pollution components,non-soluble deposit density(NSDD),temperature(T),and atmospheric pressure(P)was obtained.On this basis,the GA-BP neural network prediction model was established.P,SCD,NSDD,CaSO_(4) mass fraction(w(CaSO_(4))),and T were taken as input parameters,50%flashover voltage(U_(50%))of the insulator was taken as output parameters.The results showed that the prediction deviation was less than 10%,which meets the basic engineering requirements.The results could not only provide early warning for the anti-pollution flashover work of the railway power supply department,but also be used as an auxiliary contrast to verify the accuracy of the results of the experiments,and provide a theoretical basis for the classification of pollution levels in different regions.
基金Supported by Project of National Natural Science Foundation of China"QTL Mapping Combined with GWAS Strategy to Explore Major Regulation Genes for Glucosinolate Metabolism in Brassica juncea"(31560422)Science and Technology Foundation of Guizhou Province of China"Positioning,Mining and Metabolic Mechanism of Major Genes Regulating Glucosinolate from Leaves and Seeds of Brassica rapa"[Qian Ke He J Zi(2015)2052]+2 种基金Scientific Research Foundation for Returned Scholars,Ministry of Education"Mining of glucosinolate-regulated Genes in Brassica napus and Analysis of Its Expression Dynamics"[Jiao Wai Si Liu(2015)1098]Project for Doctoral Talent Introduction Fund of Guizhou University"Screening of Glucosinolate Content in Brassica napus Varieties and Development of Associated Markers"[Gui Da Ren Ji He Zi(2014)14]Construction Program of Biology First-class Discipline in Guizhou(GNYL[2017]009)
文摘In order to screen and identify excellent breeding resources and provide basic materials for Brassica rapa breeding,the contents of erucic acid,oleic acid and glucosinolate in 84 kinds of B. rapa were determined by near-infrared spectroscopy,and the correlations among them were also analyzed. The results showed that the content of erucic acid and oleic acid were significantly negatively correlated,the contents of erucic acid and glucosinolate were significantly positively correlated,while the contents of oleic acid and glucosinolate were significantly negatively correlated; principal component analysis( PCA) were performed on the population materials,factors 1 and 2 were extracted for plotting,factor 1 and factor 2 could explain 73. 7% and 23. 2% of the phenotypic variation,respectively; through cluster analysis,79 materials aggregated to form group I,and five special variants deviated from the population. The variation of erucic acid,oleic acid and glucosinolates in B. rapa populations was rich and there was significant correlation. Through cluster analysis,five excellent B. rapa breeding materials( No. 32,No. 45,No. 46,No. 50,and No. 59) were screened.
基金supported by National Key Research and Development Program of China(2022YFD1300600)the Agricultural Science and Technology Innovation Program of CAAS,China(IFR-ZDRW202303)+1 种基金Beijing Innovation Consortium of Agriculture Research System(BAIC07-2023)Xinjiang key Research and Development Program(2022B02039-3)
文摘Low-fishmeal and protein-saving diets are two prominent nutritional strategies utilized to address challenges related to the scarcity and sustainability of protein sources in aquaculture.However,these diets have been associated with adverse effects on the growth performance,feed utilization,and disease resistance of aquatic animals.To mitigate these challenges,exogenous protease has been applied to enhance the quality of diets with lower protein contents or fishmeal alternatives,thereby improving the bioavailability of nutritional ingredients.Additionally,protease preparations were also used to enzymatically hydrolyze fishmeal alternatives,thus enhancing their nutritional utilization.The present review aims to consolidate recent research progress on the use of protease in aquaculture and conclude the benefits and limitations of its application,thereby providing a comprehensive understanding of the subject and identifying opportunities for future research.
基金the support from the National Natural Science Foundation of China(Grant Nos.82201115,81921002)China Postdoctoral Science Foundation(No.2021M702166)the Innovative Research Team of High-level Local Universities in Shanghai,Oral and Maxillofacial Regeneration and Functional Restoration.
文摘Caries is one of the most prevalent human diseases,resulting from demineralization of tooth hard tissue caused by acids produced from bacteria,and can progress to pulpal inflammation.Filling restoration with dental resin composites(DRCs)is currently the most common treatment for caries.However,existing DRCs suffer from low fracture strength and lack comprehensive anti-caries bioactivity including remineralization,pulp protection,and anti-cariogenic bacteria effects.In this study,inspired by plant roots’ability to stabilize and improve soil,fluorinated urchin-like hydroxyapatite(FUHA)with a three-dimensional whisker structure and bioactive components of calcium,phosphorus,and fluorine was designed and synthesized by a dynamic self-assembly method.Furthermore,versatile FUHA particles with different loading fractions were used as functional fillers to fabricate methacrylate-based DRCs,where the urchin-like hydroxyapatite(UHA)filled DRCs and commercial DRCs(Z350XT and BEAUTIFIL II)served as the control groups.The results demonstrated that FUHA with 50 wt%loading in resin matrix endowed DRC(F5)with excellent physicochemical properties,dentin remineralization property,cell viability,promotion of dental pulp stem cells mineralization,and antibacterial properties.Meanwhile,F5 also presented good clinical handling and aesthetic characteristics.Therefore,structure/functional-integrated FUHA filled DRCs have potential as a promising strategy for tooth restoration and anti-caries bioactivity.