Synthesis of multifunctional additives for solid propellants:Structure,properties and mechanism

To simplify the composite propellant formulation and address the current issue of the single-functionality present in existing additives,the multi-cyano,amine-based polybutadiene(AEHTPB-CN)was prepared based on AEHTPB by adopting appropriate synthesis strategies.By replacing 10% of HTPB binder in the propellant formulation,it can effectively enhance the interfacial bond strength between the propellant binder matrix and solid fillers(AP(ammonium perchlorate)and RDX(cyclotrimethylene-trinitramine)),the mechanical properties of the HTPB/AP/RDX/Al propellant were superior to blank control propellant with an improvement of 35.4% in tensile strength,62.0% enhancement in elongation at break,and reduce the propellant burn rate by 10.7% with any energy loss.The function mechanism of AEHTPB-CN was systematically elucidated through experiments and computer simulation techniques.The results show that the tertiary amine group in AEHTPB-CN can react with AP to form ammonium ionic bonds,and the hydroxyl and cyano groups can form hydrogen bonding interactions with AP,which enables AEHTPB-CN to be firmly adsorbed on the AP surface through chemical and physical interactions.For RDX,the interfacial bonding effect of AEHTPB-CN is attributed to their ability to form C-H···N≡C weak hydrogen bonding interaction between the cyano group and RDX methylene group.

Heteronuclear Magnetisms with Ultracold Spinor Bosonic Gases in Optical Lattices

Motivated by recent realizations of spin-1 NaRb mixtures in the experiments[Phys.Rev.Lett.114,255301(2015);Phys.Rev.Lett.128,223201(2022)],we investigate heteronuclear magnetism in the Mott-insulating regime.Different from the identical mixtures where the boson statistics only admits even parity states from angular momentum composition,for heteronuclear atoms in principle all angular momentum states are allowed,which can give rise to new magnetic phases.While various magnetic phases can be developed over these degenerate spaces,the concrete symmetry breaking phases depend on not only the degree of degeneracy but also the competitions from many-body interactions.We unveil these rich phases using the bosonic dynamical mean-field theory approach.These phases are characterized by various orders,including spontaneous magnetization order,spin magnitude order,singlet pairing order,and nematic order,which may coexist specially in the regime with odd parity.Finally we address the possible parameter regimes for observing these spin-ordered Mott phases.

Effects of rearing system and antibiotic treatment on immune function,gut microbiota and metabolites of broiler chickens

Background:In China,cage systems with a high space utilization have gradually replaced ground litter systems,but the disease incidence of chickens in cages is higher.Broilers in the ground litter pens may be stimulated by more environmental microbes during the growth process and show strong immune function and status,but knowledge of which microbes and their metabolites play an immunomodulatory role is still limited.This study aimed to explore the differences and correlations in the immune function,gut microbiota and metabolites and the importance of gut microbiota of broilers raised in cages and ground litter pens.Methods:The experiment involved a 2×2 factorial arrangement,with rearing systems(cages or ground litter pens)and antibiotic treatment(with or without broad-spectrum antibiotics in drinking water)as factors.Results:The results showed that,compared with the cage group,the ground litter broilers had stronger nonspecific immune function(Macrophages%and NO in blood),humoral immune function(IgG in blood,LPS stimulation index in ileum)and cellular immune function(T%,Tc%,ConA stimulation index and cytokines in blood).Antibiotic(ABX)treat-ment significantly reduced nonspecific immune function(Macrophages%and NO in blood,iNOS and Mucin2 mRNA expression in ileum),humoral immune function(IgG in blood and sIgA in ileum)and cellular immune function(T%and cytokines in blood,Th and Tc ratio,TLRs and cytokines mRNA expression in ileum).Furthermore,the ground litter broil-ers had higherαdiversity of microbiota in ileum.The relative abundance of Staphylococcus,Jeotgalicoccus,Jeotgalibaca and Pediococcus in the ileum of ground litter broilers were higher.ABX treatment significantly reduced theαdiversity of ileal microbiota,with less Chloroplast and Mitochondria.In addition,the levels of acetic acid,isobutyric acid,kynurenic acid and allolithocholic acid in the ileum of ground litter broilers were higher.Spearman correlation analysis showed that Jeotgalibaca,Pediococcus,acetic acid,kynurenic acid and allolithocholic acid were related to the immune function.Conclusions:There were more potential pathogens,litter breeding bacteria,short-chain fatty acids,kynurenine,allolithocholic acid and tryptophan metabolites in the ileum of broilers in ground litter pens,which may be the reason for its stronger immune function and status.

Debranching enzymes decomposed corn arabinoxylan into xylooligosaccharides and achieved prebiotic regulation of gut microbiota in broiler chickens

Background Corn arabinoxylan(AX)is a complicated and multibranched antinutritional factor,thereby proving the use of endo-xylanase(EX)to be marginally valid.This study focused on specific types of AX-degrading enzymes(ADEs)to exert the synergy of debranching enzymes and track the prebiotic potential of enzymatic hydrolysates.This study investigated the effects of ADEs on the growth performance,intestinal histomorphology,absorption functions,changes in polysaccharide components,fermentation,and gut microbiota of broiler chickens.Five hundred seventysix five-day-old Arbor Acres male broiler chickens were randomly allocated into eight treatments with six replicates each.Corn basal diets supplemented with or without enzymes were fed for a 21-day period,specifically including EX,its compatible use with arabinofuranosidase(EXA)or ferulic acid esterase(EXF),and compound groups with the above three enzymes(XAF).Results Specific ADEs stimulated the jejunal villus height and goblet cell number and evidently decreased the crypt depth(P<0.05),while the ratio of ileal villus height to crypt depth was significantly increased in EXF(P<0.05).Maltase activities of ileal mucosa in XAF groups were extremely enhanced(P<0.01),and EX boosted the activity of Na+-K+ATPase in the small intestine(P<0.01).The insoluble AX concentrations comparatively lessened,thereby notably raising the sundry xylooligosaccharide(XOS)yield in the ileal chyme(P<0.05),which was dominant in xylobiose and xylotriose.Improvements in the abundance and diversity of ileal microbial communities within the EXA,EXF,and XAF treatments were observed(P<0.05).Positive correlations between microbiota and XOS were revealed,with xylobiose and xylotriose being critical for ten beneficial bacteria(P<0.05).EXF increased the BWG and FCR of broiler chickens in this phase(P<0.05),which was attributed to the thriving networks modified by Lactobacillus.The intracecal contents of acetic acid,butyric acid,and propionic acid were greatly enhanced in most ADE groups,such as EXF(P<0.05).Conclusions Debranching enzymes appreciably targeted corn AX to release prebiotic XOS in the posterior ileum and facilitated intracaecal fermentation.It was beneficial for improving gut development,digestion and absorption and modulating the microflora to promote the early performance of broiler chickens.

Influence of starch sources and dietary protein levels on intestinal functionality and intestinal mucosal amino acids catabolism in broiler chickens

Background: There is growing interest in carbohydrate and protein nutrition to enhance the efficiency of animal production.Reduced-crude protein diets depress environmental pollution and feeding cost,but the challenge to their adoption is maintaining digestive function and growth performance of birds.The present study was conducted to evaluate the influence of different dietary starch sources and protein levels on intestinal functionality and mucosal amino acid catabolism.Methods: Six dietary treatments,based on maize and soybean meal,were offered to 360 AA+male chicks from 6 to 35 d post-hatch as a 3 × 2 factorial array.Either waxy rice or amylose was added to a conventional maize-soy diet to provide three sources of starch with different digestion rates and relatively high and low dietary protein levels.Growth performance,parameters of intestinal functionality and concentrations of free amino acid in the portal circulation were determined.Results: In the grower phase,starch source influenced(P < 0.02) weight gain as diets containing amylose supported significantly higher weight gains than waxy rice.Significant increase of ileal ATP concentrations and Na^+/K^+-ATPase activity were found in amylose treatment.Also,amylose decreased BrdU positive cell numbers and down-regulated m RNA expression for CASP-3.GOT activity in the ileum was higher(P < 0.01) in birds offered low protein diets and there was a trend(P = 0.057) for waxy rice as a starch source to increase ileal GOT activities.There was a significant influence on the concentration of seventeen amino acids in the portal circulation with tryptophan the one exception.Waxy rice as a starch source generated 13.6% and 22.4% numerically higher concentrations of non-essential amino acids than maize and amylose,respectively.Conclusions: Amino acid catabolism in the gut mucosa is subject to nutritional regulation.Given that amino acids can be spared from catabolism in the gut mucosa by supplementation of amylose,it follows their post-enteral availability would be improved and intestinal energy would be derived more efficiently from glucose.

Generation of 88 as Isolated Attosecond Pulses with Double Optical Gating

Isolated attosecond pulses with a duration of 88 as are generated in the spectral range of 29–72 eV using double optical gating technique.The gate width is set to be shorter than half the optical cycle to avoid carrier envelop phase stabilization of the 4.2 fs driving laser pulses centered at 800 nm.The attosecond pulse duration is measured with the technique of frequency resolved optical gating for complete reconstruction of attosecond bursts.

Effects of dietary tryptophan and stocking density on the performance,meat quality,and metabolic status of broilers

Background： Highly automated cage-rearing systems are becoming increasingly popular in China. However, a high stocking density can cause oxidative stress and decrease broiler performance. The tryptophan （TRP） derivative 5-hydroxytryptophan （5-HT） has been shown to preserve membrane fluidity in birds suffering from oxidative stress Therefore, this experiment was conducted to determine the effects of dietan/TRP supplementation on performance, breast meat quality and oxidative stress in broilers reared in cages with a high or low stocking density. Methods： Female Arbor Acres broilers （25-d-old, n = 144） were randomly allocated to 1 of 4 treatments. The birds were fed a diet based on corn, soybean meal, cottonseed meal and corn gluten meal containing either 0.18 or 0.27% TRP and were housed with stocking densities of 11 or 15.4 birds/m2 in a 2 x 2 factorial experiment. Broiler performance was evaluated from d 25 to 42. Eight birds from each treatment were slaughtered on d 42 and plasma and breast muscle samples were collected to measure biochemical indices. Results： A higher stocking density tended to be associated with reduced weight gain （P 〈 0.10）, and significantly increased plasma glutamic-pyruvic transaminase （GPT） activity （P 〈 0.001）. Increased dietary TRP significantly reduced the activities of lactic dehydrogenase and GPT while increasing total cholesterol in the plasma （P 〈 0.01）, reducing drip loss of breast muscle （P 〈 0.10） and improving feed efficiency （P 〈 0.10）. Conclusions： An increase in dietary TRP, ].S-fold higher than the standard supplementation level, can alleviate oxidative stress as well as improve welfare and feed efficiency in broilers reared in cages with a high stocking density.

Effect of dietary nonphytate phosphorus on laying performance and small intestinal epithelial phosphate transporter expression in Dwarf pink-shell laying hens

This study examined the effects of various levels of dietary nonphytate phosphorus on laying performance and the expression patterns of phosphorus metabolism related genes in Dwarf pink-shell Jaying hens. A total of 405 28-week-old Dwarf pink-shell laying hens were fed the same corn-soybean basal meals but containing 0.20%, 0.25%, 0.30%, 0.35% or 0.40% nonphytate phosphorus. The results showed that feed intake, egg production, and average egg weights were quadratically correlated with dietary nonphytate phosphorus content （P 〈 0.05）, and the highest egg production, feed intake and average egg weights were achieved when dietary nonphytate phosphorus was at 0.3% （P 〈 0.05）. mRNA expression of intestinal sodium phosphorus co-transporter linearly decreased when dietary nonphytate phosphorus increased, mRNA and protein expression of intestinal calbindin and vitamin D receptor correlated quadratically with dietary nonphytate phosphorus, and the highest expression was found when dietary available phosphorus was at 0.2,5% to 0.3%. In conclusion, the ideal phosphorus requirement for Dwarf pink-shell layer hens is estimated to be 0.3% in a corn-soybean diet. With this level of phosphorus supplementation, calbindin and vitamin D receptor reached their highest expression.

Supplementation of amylase combined with glucoamylase or protease changes intestinal microbiota diversity and benefits for broilers fed a diet of newly harvested corn

Background: The effect of amylases combined with exogenous carbohydrase and protease in a newly harvested corn diet on starch digestibility, intestine health and cecal microbiota was investigated in broiler chickens.Methods: Two hunderd and eighty-eight 5-day-old female chickens were randomly divided into six treatments: a newly harvested corn-soybean meal diet(control); control supplemented with 1,500 U/g α-amylase(Enzyme A);Enzyme A + 300 U/g amylopectase + 20,000 U/g glucoamylase(Enzyme B); Enzyme B + protease 10,000 U/g(Enzyme C); Enzyme C + xylanase 15,000 U/g(Enzyme D); and Enzyme D + cellulase 200 U/g + pectinase 1,000 U/g(Enzyme E). Growth performance, starch digestibility, digestive organ morphology, and intestinal microbiota were evaluated in the birds at 16 and 23 d of age.Results: Compared with the control diet, supplementation with Enzyme A significantly decreased ileum lesion scoring at 16 d of age(P < 0.05); supplementation with Enzyme B or Enzyme C showed positive effects on ileal amylopectin and total starch digestibility(P < 0.05); Broilers fed with a diet supplemented with Enzyme D had a tendency to decrease body weight gain at 23 d. Enzyme E supplementation improved lesion scoring of jejunum and ileum at 16 d(P < 0.05), and increased ileal amylopectin or total starch digestibility at 23 d(P < 0.05).Supplementation of enzymes changed cecal microbiota diversity. High numbers of Campylobacter, Helicobacter and Butyricicoccus, Anaerostipes and Bifidobacterium, Sutterella and Odoribacter were the main genera detected in supplementations with Enzymes B, C, D, and E respectively.Conclusions: Supplementation with amylase combined with glucoamylase or protease showed a beneficial effect on starch digestibility and intestinal microbiota diversity, and increased growth of broilers fed with newly harvested corn.

Poultry fat decreased fatty acid transporter protein mRNA expression and affected fatty acid composition in chickens

Background： A study was undertaken to examine the effects of poultry fat （PF） compared with those of soybean oil （SBO） on intestinal development, fatty acid transporter protein （FATP） mRNA expression, and fatty acid composition in broiler chickens. A total of 144 day-old male commercial broilers were randomly allocated to 2 treatment groups （6 replicates of 12 chicks for each treatment） and fed isocaloric diets containing 3.0% PF or 2.7% SBO at 0 to 3 wk and 3.8% PF or 3.5% SBO at 4 to 6 wk, respectively. Results： PF had no influence on intestinal morphology, weight, or DNA, RNA, or protein concentrations at 2, 4, and 6 wk of age. However, compared with SBO, PF significantly decreased FATP mRNA abundance at 4 wk （P= 0.009） and 6 wk of age （P〈 0.001）; decreased liver fatty acid-binding protein （L-FABP） mRNA abundance at 6 wk of age （P = 0.039）; and decreased C18：2 （P = 0.015）, C18：3 （P 〈 0.001）, C20：2 （P = 0.018）, ∑-polyunsaturated fatty acids （∑-PUFA） （P= 0.020）, and the proportion of PUFA （P 〈 0.001） in the intestinal mucosa and decreased C18：2 （P = 0.010）, C 18：3 （P 〈 0.001 ）, C20：2 （P 〈 0.001 ）, Z-P U FA （P = 0.005）, and the proportion of P U FA （P 〈 0.001 ） in breast muscle at 6 wk of age.

Insights into the proteomic profile of newly harvested corn and metagenomic analysis of the broiler intestinal microbiota

Background:The use of newly harvested corn in feed causes wet droppings in broilers and increased feed cost which was termed as“new season grain problem”.The present study was conducted to evaluate the proteomic profile of newly harvested corn and the subsequent influence on intestinal microbiol community for broiler chickens.Methods:Newly harvested corn stored for either half a month(HM)or two months(TM)was used,and the pasting properties,total soluble sugars,and proteomic analysis technology was used to explore the influence of storage on natural aging corn properties.Additionally,seventy-two 7-day-old Ross 308 male broiler chicken were fed with different stored corn.Apparent metabolizable energy(AME),digesta viscosity,intestinal morphology and microbiota were examined to explore the influence of feed corn storage on broiler chickens.Results:Pasting properties in the TM corn exhibited decreased viscoelastic properties.Proteomic studies found a total of 26 proteins that were differentially expressed between the two treatment groups.Proteins involved in starch and polysaccharides biosynthesis were upregulated in TM compared with HM.Chickens fed on TM diet had higher relative energy utilization compared to the HM birds.With increased corn storage,the relative digesta viscosity decreased significantly(P≤0.05).The total number of goblet cells and lymphocytes was lower in chickens fed the TM diet.The microbiota data showed that the TM chickens had decreased abundance of diarrheal bacteria such as Hungatella hathewayi and Bacteroides fragilis,and increased butyrate-producing bacteria such as Alistipes compared to the HM chickens.Conclusions:Storage of newly harvested corn induced the synthetic reaction of large molecules and changed the solubility of starch and protein with increasing soluble sugars and decreasing pasting properties that may improve the fermentation of intestinal microbiota,improve the energy utilization and protect gut health without the risk of diarrhea.

Real-Time Observation of Electron-Hole Coherence Induced by Strong-Field Ionization

We introduce and demonstrate a new approach to measure the electron-hole dynamics and coherence induced by strong-field ionization using hole-assisted high-harmonic spectroscopy.The coherent driving of the infrared and XUV pulses correlates the dynamics of the core-hole and the valence-hole by coupling multiple continua,which leads to the otherwise forbidden absorption and emission of high harmonics.An analytical model is developed based on the strong-field approximation by taking into account the essential multielectron configurations.The emission spectra from the core-valence transition and the core-hole recombination are found to modulate strongly as functions of the time delay between the two pulses,suggesting that the coherent electron wave packets in multiple continua can be utilized to temporally resolve the core-valence transition in attoseconds.

Nonresonant Multiphoton Ionization of Stark Decelerated Molecules by Femtosecond Laser Pulses

Nonresonant multiphoton ionization by femtosecond laser pulses can be applied to any molecule virtually,thereby greatly enhancing the scope of Stark decelerated molecules.For comparison,we detect decelerated and trapped ammonia molecules using two different schemes:(ⅰ) nonresonant multiphoton ionization using intense femtosecond(fs) pulses in the near infrared,and(ⅱ) resonance-enhanced multiphoton ionization using nanosecond(ns) pulses from a tunable UV laser.The observed number of ions per shot for both schemes is similar.The fs laser detection scheme suffers from an increased background,which can be effectively eliminated by subsequent mass and velocity selection.To determine the detection volume of the ns laser detection scheme,we present measurements in which the decelerated ammonia molecules are bunched to a packet with a longitudinal spread well below~100 μm.It is concluded that the detection volume for the ns laser detection scheme is 1.5-2 times larger than that of the fs laser detection scheme.

Ionic self-diffusion coefficient and shear viscosity of high-Z materials in the hot dense regime

High-Zmaterials exhibit a broad range of variation of the charge state in the hot dense regime,and so ionic structures becomecomplexwith increasing density and temperature owing to ionization.Taking high-Z uranium as example,we study its electronic and ionic structures in the hot dense regime by combining an average-atommodelwith the hypernetted chain approximation.The electronic structure is described by solving theDirac equation,taking account of relativistic effects,including broadening of the energy levels,and the effect of other ions via correlation functions.On the basis of the electronic distribution around a nucleus,the ion pair potential is constructed using the modified Gordon–Kim model in the frame of temperaturedependent density functional theory.Because of the presence of ion–ion strong coupling,the bridge function is included in the hypernetted chain approximation,whichis usedto calculate the correlation functions.To take account of the influenceon transportpropertiesof the strong correlation of electrons with highly charged ions,we perform both classical and Langevin molecular dynamics simulations to determine ion self-diffusion coefficients and the shear viscosity,using theGreen–Kubo relation and an ion–ion pair potential with good convergence.We show that the influence of electron–ion collisions on transport properties becomes more important as the free electron density increases owing to thermal ionization.

High amylose to amylopectin ratios in nitrogen-free diets decrease the ileal endogenous amino acid losses of broiler chickens

This study explored the variation of ileal endogenous amino acid(IEAA)losses and its influencing factors in chickens offered nitrogen-free diets(NFD)containing different ratios of amylose to amylopectin(AM/AP).A total of 252 broiler chickens at 28 d old were randomly allocated into 7 treatment groups for a 3-d trial.The dietary treatments included a basal diet(control),a NFD containing corn starch(CS),and 5NFD with AM/AP ratios of 0.20,0.40,0.60,0.80,and 1.00,respectively.As the AM/AP ratio increased,the IEAA losses of all AAs,starch digestibility and maltase activity linearly decreased(P<0.05),but the DM digestibility linearly and quadratically decreased(P<0.05).Compared with the control,the NFD increased the number of goblet cells and its regulatory genes mucin-2 and krüppel-like factor 4(KLF-4)while decreasing serum glucagon and thyroxine concentrations,ileal villus height,and crypt depth(P<0.05).Additionally,NFD with lower AM/AP ratios(0.20 and 0.40)decreased the ileal microbiota species richness(P<0.05).In all NFD groups,the number of Proteobacteria increased whereas the abundance of Firmicutes dropped(P<0.05).However,the broilers in the AM/AP 0.60 group were closer to the digestive physiological state of chickens fed the control diet,with no significant change in maltase activity and mucin-2 expression(P<0.05).In conclusion,increasing AM/AP ratio in a NFD decreased the IEAA losses and the apparent ileal digestibility of starch but inevitably resulted in malnutrition and disruption of gut microbiota homeostasis.This study recommends AM/AP in NFD at 0.60 to measure IEAA of broiler chickens.

Interaction-induced topological transition in spin-orbit coupled ultracold bosons

Recent experiments in ultracold atoms have reported the realization of quantum anomalous Hall phases in spin-orbit coupled systems.Motivated by such advances,we investigate spin-orbit coupled Bose-Bose mixtures in a two-dimensional square optical Raman lattice.Complete phase diagrams are obtained via a nonperturbative real-space bosonic dynamical mean-field theory.Various quantum phases are predicted,including Mott phases with z-ferromagnetic,xy-antiferromagnetic and vortex textures,and superfluid phases with the exotic spin orders,induced by the competition between the lattice hopping and spin-orbit coupling.To explain the underlying physics in the Mott regime,an efective Hamiltonian is derived based on second-order perturbation theory,where pseudospin order stems from the interplay of efective Dzyaloshinskii-Moriya superexchange and Heisenberg interactions.In the presence of the Zeeman field,the competition of strong interaction and Zeeman energy facilitates a topological phase,which is confirmed both by the nontrivial topological Bott index and spectral function with topological edge states.Our work indicates that spin-orbit coupling can induce rich non-Abelian topological physics in strongly correlated ultracold atomic systems.

Author Correction: Characterization of domain distributions by second harmonic generation in ferroelectrics

Correction to:npj Computational Materials https://doi.org/10.1038/s41524-018-0095-6,published online 24 July 2018 In this article the affiliation details for author Yinghao Chu were incorrectly given as‘Department of Materials Science and Engineering,National Chiao Tung University,30010 Hsinchu,Taiwan’but should have been‘Department of Materials Science and Engineering,National Chiao Tung University,30010 Hsinchu,Taiwan,China’.The original article has been corrected.

Retinol is involved in the intestinal regeneration and strengthens the intestinal barrier during refeeding in broiler chickens

Fasting is typically used before feeding metabolizable energy assessment in broilers.Previous studies have shown that fasting cause atrophy of the intestinal villus.Whether fasting affects intestinal permeability during refeeding by altering barrier function and nutrient absorption is of concern.Here,23-d-old broilers were randomly assigned to 5 treatments,fasted for 0,12,24,36,and 48 h,respectively,and then refed for 2 d,to study the impact of different duration of fasting on the intestinal regeneration and barrier function during refeeding.Results showed that the intestinal morphology in fasted birds was recovered in 2 d of refeeding at most.As fasting durations increased,enterocytes per intestinal villus were linearly and quadratically increased(both P<0.05),whereas goblet cells per intestinal villus was linearly decreased(both P<0.05).Besides,the mRNA level of lysozyme was linearly decreased as fasting durations increased during refeeding(both P<0.05),while quadratically increased mucin 2 was observed only after 1 d of refeeding(P<0.05).Linear increase effects were observed for claudin 2 and zonula occludens-1with increased fasting durations after 1 d of refeeding(all P<0.05),and linear and quadratical effects were observed for claudin 2 at 2 d of refeeding(both P<0.05).Besides,we found that intestinal permeability to creatinine,4 and 70 kD dextran were linearly and quadratically decreased with increased fasting durations at 6 h and 1 d of refeeding(all P<0.05).Furthermore,jejunum proteomic from birds refed for 6 h showed that birds fasted for 36 h showed increased antimicrobial peptides and upregulated retinol metabolism when compared to the nonfasted birds(P<0.05).Further study showed that retinyl ester catabolism was inhibited during fasting and enhanced during refeeding.Results of intestinal organoid culture showed that retinol benefits the cell proliferation and enterocyte differentiation.In conclusion,the intestinal permeability to small and large molecules was decreased during refeeding by strengthening the intestinal barrier function,and the activated retinol metabolism during refeeding is involved in the intestinal regeneration and strengthens the intestinal barrier.

Field intensity dependence of the dissociative multiple ionization of argon dimers in strong femtosecond laser fields

The dissociative ionization of Ar dimers is investigated in femtosecond laser fields with intensities from 260 to 1020 TW/cm^(2).The three-dimensional momentum and kinetic-energy release of fragmental ions generated from the channels Ar_(2)^(2+)→Ar^(+)+Ar^(+),Ar_(2)^(3+)→Ar^(2+)+Ar^(+),and Ar_(2)^(4+)→Ar^(2+)+Ar^(2+)were measured with a cold-target recoil-ion momentum spectrometer.It is shown that the laser intensity significantly modulates the kinetic energies and angular distributions of fragmental ions from dissociative double ionization.Laser-induced charge-transfer following one-site double ionization contributes relatively more to the dissociative double ionization at lower laser intensity.The calculation results of a one-dimensional model based on the WKB approximation suggest that the charge transfer is suppressed at higher laser intensity due to the core polarization effect.In addition,double,triple,and quadruple dissociative ionizations of Ar dimers are accompanied by frustrated-tunneling ionization that increases with the laser intensity.

Effect of storage time on the characteristics of corn and efficiency of its utilization in broiler chickens

Corn is one of the staple food and feed ingredients in China, therefore its storage is of particular importance. Corn is typically stored for 2 or more years in national barns before it is sold as a food or feed ingredient. However, the effects of stored corn in national barns on the animal performance and nutrient utilization have not been investigated thus far. This study attempted to determine the effects of storage time on the chemical and physical characteristics of corn and its nutritional value, broiler growth performance, and meat quality. Corn grains used in the present study were stored for 4 different periods,from 2 to 5 yr, under the same conditions in a building at the Beijing National Grain Storage Facility. A total of 240 birds in Exp. 1 and 90 birds in Exp. 2 were used to compare the effects of storage time on the utilization of nutrients of corn, the performance, and meat quality of broilers. The content of starch, crude protein, amino acids, fatty acids, and test weight generally decreased with increasing storage time. Corn stored for over 4 yr showed decreased catalase(CAT) and peroxidase(POD) activities and increased fat acidity. Body weight gain(BWG) and European production index(EPI) of broilers from 0 to 3 wk tended to decrease linearly with storage time(0.05 < P < 0.10), and the BWG and EPI of broilers from 4 to 6 wk decreased quadratically(P < 0.05), whereas feed conversion ratio(FCR) increased with storage time(P < 0.05). The FCR, performance, and EPI of broilers positively correlated with CAT activity(P < 0.05), and negatively correlated with fat acidity(P < 0.05). Drip loss of breast muscle increased linearly with corn storage time(P < 0.001); however, pH decreased linearly with corn storage time. Drip loss had a strong negative correlation with POD(P < 0.05). There were no significant differences of the storage length on metabolizable energy(ME), digestibility of crude protein, and starch(P > 0.05). The digestibility of histidine and arginine, and C18:2 and C18:3 changed quadratically with storage time(P < 0.05).Collectively, the results suggest that the use of corn stored for 4 yr in animal feed decreased the performance and meat quality of broilers. Fat acidity, CAT, and POD activities can be used as indexes for evaluating the storage quality of corn.