The BMP2 prodomain promotes dimerization and cleavage of BMP6 homodimers and BMP2/6 heterodimers in vivo.

Bone morphogenetic protein 2 (BMP2) and BMP6 are key regulators of systemic iron homeostasis. All BMPs are generated as inactive precursor proteins that dimerize and are cleaved to generate the bioactive ligand and inactive prodomain fragments, but nothing is known about how BMP2 or BMP6 homodimeric or heterodimeric precursor proteins are proteolytically activated. Here, we conducted in vitro cleavage assays, which revealed that BMP2 is sequentially cleaved by furin at two sites, initially at a site upstream of the mature ligand, and then at a site adjacent to the ligand domain, while BMP6 is cleaved at a single furin motif. Cleavage of both sites of BMP2 is required to generate fully active BMP2 homodimers when expressed in Xenopus embryos or liver endothelial cells, and fully active BMP2/6 heterodimers in Xenopus . We analyzed BMP activity in Xenopus embryos expressing chimeric proteins consisting of the BMP2 prodomain and BMP6 ligand domain, or vice versa. We show that the prodomain of BMP2 is necessary and sufficient to generate active BMP6 homodimers and BMP2/6 heterodimers, whereas the BMP6 prodomain cannot generate active BMP2 homodimers or BMP2/6 heterodimers. We examined BMP2 and BMP6 homodimeric and heterodimeric ligands generated from native and chimeric precursor proteins expressed in Xenopus embryos. Whereas native BMP6 is not cleaved when expressed alone, it is cleaved to generate BMP2/6 heterodimers when co-expressed with BMP2. Furthermore, BMP2-6 chimeras are cleaved to generate BMP6 homodimers. Our findings reveal an important role for the BMP2 prodomain in dimerization and proteolytic activation of BMP6.

Adsorption thermodynamics and kinetics of nanomaterials: theory and experimental insight into nano-effect.

Nanomaterials have excellent adsorption performance due to nano-effect and have been widely used in many fields. The adsorption performance of nanomaterials depends on their adsorption thermodynamics and kinetics. Here, the thermodynamic and kinetic equations of adsorption for spherical nanoparticles are first derived in theory. The mechanisms and regularities of influences of nano-effect on thermodynamics and kinetics, using nano-CdS adsorption of methylene blue as a probe, were investigated. The results show that there are significant influences of nano-effect (i.e., interface area effect and interface tension effect) on the thermodynamics and kinetics of nanoparticle adsorption. When the particle radius is larger and beyond the nanometer scale (∼100 nm), the nano-effect can be neglected. When the radius of the nanoparticle is within 10-50 nm, the nano-effect of adsorption is mainly the interface area effect. When the radius is less than 10 nm, the influences of both the interface area effect and the interface tension effect on adsorption thermodynamics and kinetics become more significant. The theoretic equations and experimental insights in the present work could provide a significant basis and reference for improving and perfecting the adsorption theory involving nanomaterials and provide guidelines for the explanations of adsorption mechanisms as well as the selection of adsorbents.

Design and testing of a humanized porcine donor for xenotransplantation.

Recent human decedent model studies1,2 and compassionate xenograft use3 have explored the promise of porcine organs for human transplantation. To proceed to human studies, a clinically ready porcine donor must be engineered and its xenograft successfully tested in nonhuman primates. Here we describe the design, creation and long-term life-supporting function of kidney grafts from a genetically engineered porcine donor transplanted into a cynomolgus monkey model. The porcine donor was engineered to carry 69 genomic edits, eliminating glycan antigens, overexpressing human transgenes and inactivating porcine endogenous retroviruses. In vitro functional analyses showed that the edited kidney endothelial cells modulated inflammation to an extent that was indistinguishable from that of human endothelial cells, suggesting that these edited cells acquired a high level of human immune compatibility. When transplanted into cynomolgus monkeys, the kidneys with three glycan antigen knockouts alone experienced poor graft survival, whereas those with glycan antigen knockouts and human transgene expression demonstrated significantly longer survival time, suggesting the benefit of human transgene expression in vivo. These results show that preclinical studies of renal xenotransplantation could be successfully conducted in nonhuman primates and bring us closer to clinical trials of genetically engineered porcine renal grafts.

The epithelial polarity genes frazzled and GUK-holder adjust morphogen gradients to coordinate changes in cell position with cell fate specification.

Morphogenetic gradients specify distinct cell populations within tissues. Originally, morphogens were conceived as substances that act on a static field of cells, yet cells usually move during development. Thus, the way cell fates are defined in moving cells remains a significant and largely unsolved problem. Here, we investigated this issue using spatial referencing of cells and 3D spatial statistics in the Drosophila blastoderm to reveal how cell density responds to morphogenetic activity. We show that the morphogen decapentaplegic (DPP) attracts cells towards its peak levels in the dorsal midline, whereas dorsal (DL) stalls them ventrally. We identified frazzled and GUK-holder as the downstream effectors regulated by these morphogens that constrict cells and provide the mechanical force necessary to draw cells dorsally. Surprisingly, GUKH and FRA modulate the DL and DPP gradient levels and this regulation creates a very precise mechanism of coordinating cell movement and fate specification.

Encapsulated Essential Oils Improve the Growth Performance of Meat Ducks by Enhancing Intestinal Morphology, Barrier Function, Antioxidant Capacity and the Cecal Microbiota.

The objective of this study was to evaluate the effects of encapsulated essential oils (EOs) on the gut microbiota, growth performance, intestinal morphology, antioxidant properties and barrier function of meat-type ducks. A total of 320 male Cherry Valley ducks (1 day old), were randomly assigned to four dietary experimental groups with eight replicates of ten ducks each. The groups consisted of the CON group (basal diet), the HEO group (basal diet + EO 1000 mg/kg), the LEO group (basal diet + EO 500 mg/kg), and the ANT group (basal diet + chlortetracycline 50 mg/kg). Our findings indicated that ducks fed with EO 1000 mg/kg had greater average daily feed intake (ADFI), average daily gain (ADG), and body weight (BW) and a lower feed conversion ratio (FCR) than the other groups. The serum concentration of TG reduced in the HEO (p > 0.05) and LEO (p < 0.05) groups on day 42, while the concentration of CHOL increased with the EO concentration in the LEO (p > 0.05) and HEO (p < 0.05) groups. No differences were observed in the ileal mucosa for the activities of SOD, MPO and GSH-PX after EO dietary treatment. Dietary supplementation with EOs significantly increased the villus heights (p < 0.01) and the ratio of villus height to crypt depth (c/v) in the duodenum and jejunum of ducks. Moreover, the mRNA expressions of Claudin1 and Occludin in the jejunal mucosa were observed to be higher in the LEO and HEO groups rather than the CON and ANT groups on d 42. The α diversity showed that the HEO group improved the bacterial diversity and abundance. The ß diversity analysis indicated that the microbial structures of the four groups were obviously separated. EO dietary supplementation could increase the relative abundance (p < 0.01) of the Bacteroidetes phylum, Bacteroidaceae family, and Bacteroides, Desulfovibrio, Phascolarctobacterium, and Butyricimonas genera in the cecal microbiota of ducks. We demonstrated significant differences in the bacterial composition and functional potential of the gut microbiota in ducks that were fed either an EO diet or a basal diet. Therefore, supplemented EOs was found to have a positive effect on the growth performance and intestinal health of ducks, which was attributed to the improvement in cecal microbiota, intestinal morphology, and barrier function.

Effects of a functional fatty acid blend on growth performance, intestinal morphology, and serum profiles in weaned piglets.

OBJECTIVE: The objective of this study was to determine whether dietary supplementation with a functional fatty acid blend (FA) that contains 31.4% butyric acid and 4.99% medium-chain FA improve growth performance, antioxidant capacity, immunity status, and anti-inflammatory ability in weaned piglets. METHODS: One hundred and forty-four healthy piglets (Duroc×Landrace×Yorkshire) with an average body weight (BW) of 7.98±3.43 kg were randomly divided into three groups with six replicate pens and eight piglets per pen: Normal control (NC): a corn-soybean basal diet; FA1: a basal diet supplemented with 1,000 mg/kg of a functional FA; FA2: a basal diet supplemented with 2,000 mg/kg of a functional FA. The experiment lasted for 28 d. On d 14 and 28, one piglet in each pen from NC and FA2 groups was randomly selected for antioxidative index and immunoglobulins. On d 28, one piglet in each pen from NC and FA2 groups was randomly selected for intestinal morphology and inflammatory factor. RESULTS: We observed that FA supplementation linearly increased (p<0.05) average daily gain and the final BW. There was higher (p<0.05) catalase on d 14, and immunoglobulin (Ig) A and IgM on d 28 in piglets supplemented with FA2 than in the NC group. Moreover, dietary FA2 reduced (p<0.05) crypt depth of ileum in piglets. The concentrations of tumor necrosis factor-α, interleukin (IL)-1ß, IL-8, and IL-10 in jejunum were lower (p<0.05) in the FA2 group compared with the NC group. CONCLUSION: Therefore, the overall results suggests that the FA may help to improve gut health, antioxidant status, and immune parameters resulting in the improvement of growth performance.

Effects of essential oil coated with glycerol monolaurate on growth performance, intestinal morphology, and serum profiles in weaned piglets.

OBJECTIVE: This study aimed to investigate the effects of essential oil coated with glycerol monolaurate (GML) on the growth performance, intestinal morphology, and serum profiles of weaned piglets. METHODS: A total of 144 weaned piglets (Duroc×[Landrace×Yorkshire], average weight 8.07±3.33 kg) were randomly assigned to three groups with six replicate pens and eight piglets per pen: i) CON: a corn-soybean basal diet; ii) LEG: with 1,000 mg/kg essential oil coated with GML; and iii) HEG: with 2,000 mg/kg essential oil coated with GML. RESULTS: Results showed that average daily gain was increased (p<0.05) linearly by essential oil coated with GML supplementation on day 14 to 28 and day 0 to 28 compared with the CON group. Dietary supplementation with HEG increased (p<0.05) total antioxidant capacity and catalase activity on day 14, and immunoglobulin A (IgA) and IgM concentration on day 28 and tended to increase IgG on day 28. In addition, the crypt depth in the jejunum was reduced (p<0.05), and villus height and villus height/crypt depth in the ileum were increased (p<0.05) in the HEG group compared with the CON group. Moreover, lower (p<0.05) concentrations of tumor necrosis factor-α, interferon-γ, interleukin-1ß (IL-1ß), IL-8, and IL-10 were observed in the jejunum of piglets supplemented with HEG compared with the CON group. In addition, dietary HEG tended to decrease IL-6 level in the jejunum of piglets compared with the CON group. CONCLUSION: Dietary essential oil coated with GML can improve growth performance of weaned piglets. Moreover, supplementing 2,000 mg/kg essential oil coated with GML was demonstrated to improve antioxidant ability, and intestinal morphology, and reduce jejunal inflammatory factor levels.

PINK1 regulates mitochondrial fission/fusion and neuroinflammation in ß-amyloid-induced Alzheimer's disease models.

Disrupted mitochondrial fission/fusion balance is consistently involved in neurodegenerative diseases, including Alzheimer's disease. PTEN-induced putative kinase 1 (PINK1), a mitochondrial kinase, has been reported to prevent mitochondrial injury, oxidative stress, apoptosis, and inflammation. However, to the best of our knowledge, the contribution of PINK1 to Aß-induced mitochondrial fission/fusion has not been reported. In the present study, we showed that PINK1 deficiency promoted mitochondrial fission and fusion, aggravated mitochondrial dysfunction, and promoted neuroinflammatory cytokine factor production induced by intracerebroventricular (ICV) injection of Aß25-35 in rats. In vitro experiments have also showed that Aß25-35 caused more severe cell injury in PINK1-knockdown PC12 cells. These cells suffered more extensive death when exposed to proinflammatory cytokines. Lastly, we found that PINK1 overexpression significantly inhibited mitochondrial fusion, improved mitochondrial dysfunction, and reduced neuroinflammatory cytokine production induced by Aß25-35. The current study suggests the involvement of PINK1 in Aß25-35-mediated mitochondrial dynamics and that PINK1 may be a potential target for therapies aimed at enhancing neuroprotection to ameliorate Aß25-35-induced insults.

Determination of Interfacial Tension of Nanomaterials and the Effect of Particle Size on Interfacial Tension.

The unique physical and chemical properties and performances of nanomaterials are closely related to the interfacial tension. However, there is no method to accurately measure the interfacial tension of nanomaterials. In addition, the effect of particle size on the interfacial tension of nanoparticles is unclear, and there exist conflicting conclusions about the value and sign of Tolman length. In this paper, a novel method of determining the interfacial tension (solid-liquid and solid-gas interfaces), temperature coefficient of interfacial tension, and Tolman lengths of nanomaterials by adsorption thermodynamics and kinetics was presented. The interfacial tension and its temperature coefficient of the solid-liquid interface of nano cadmium sulfide before adsorption were obtained, and further, the Tolman length was also obtained. The experimental results show that the particle size of nanoparticles has significant effects on the interfacial tension and its temperature coefficient. When the radius is larger than 10 nm, the interfacial tension and its temperature coefficient are almost constant with the decrease of the radius. When the radius is less than 10 nm, the interfacial tension decreases sharply and the temperature coefficient increases sharply with the decrease of the radius, and the temperature coefficient of the interfacial tension is negative. The Tolman length of the solid-liquid interface of nanoparticles is proved to be positive, and the particle size also has a significant effect on the Tolman length. The Tolman length decreases with the decrease of particle size. However, the effects of particle size on the Tolman length become significant only when the particle radius approach or reach the order of magnitudes of molecular (or atomic) radius. The effects of particle size on interfacial tension and Tolman length of nano cadmium sulfide obtained in this paper can provide significant references for the research and applications of interface thermodynamics of other nanomaterials.

Effect of hardening and sealing on color of chemically colored stainless steel.

A light reflection device combined with visible light spectrophotometer was used to measure the reflectance-wavelength curves of colored stainless steel after coloring, hardening and sealing. After these processes, the coordinate in CIE 1931 color coordinate system and brightness of samples were confirmed by chromatometry method, and the effects of hardening and sealing processes on color were determined. In hardening process, the thickness of coloring film increases significantly, the peaks of reflectance-wavelength curves move to the long-wave region, the hue of samples changes clockwise in CIE 1931 coordinate diagram, and the trend of saturation in hardening process is consistent with the saturation of the sample having larger potential difference. In sealing process, the thickness of film increases slightly, the peaks of reflectance-wavelength curves move to the long-wave region, the reflectivity and brightness of samples increase, the hue of samples moves clockwise in CIE 1931 coordinate diagram, and the saturation of some samples decreases.

Heat stress during late gestation disrupts maternal microbial transmission with altered offspring's gut microbial colonization and serum metabolites in a pig model.

Heat stress (HS) during gestation has been associated with negative outcomes, such as preterm birth or postnatal metabolic syndromes. The intestinal microbiota is a unique ecosystem playing an essential role in mediating the metabolism and health of mammals. Here we hypothesize late gestational HS alters maternal microbial transmission and structures offspring's intestinal microbiota and serum metabolic profiles. Our results show maternal HS alters bacterial ß-diversity and composition in sows and their piglets. In the maternal intestine, genera Ruminococcaceae UCG-005, [Eubacterium] coprostanoligenes group and Halomonas are higher by HS (q < 0.05), whereas the populations of Streptococcus, Bacteroidales RF16 group_norank and Roseburia are decreased (q < 0.05). In the maternal vagina, HS mainly elevates the proportions of phylum Bacteroidetes and Fusobacteria (q < 0.05), whereas reduces the population of Clostridiales Family XI (q < 0.05). In the neonatal intestine, maternal HS promotes the population of Proteobacteria but reduces the relative abundance of Firmicutes (q < 0.05). Moreover, the core Operational taxonomic units (OTU) analysis indicates the proportions of Clostridium sensu stricto 1, Romboutsia and Turicibacter are decreased by maternal HS in the intestinal and vaginal co-transmission, whereas that of phylum Proteobacteria and Epsilonbacteraeota, such as Escherichia-Shigella, Klebsiella, Acinetobacter, and Comamonas are increased in both the intestinal and vaginal co-transmission and the vagina. Additionally, Aeromonas is the only genus that is transmitted from environmental sources. Lastly, we evaluate the importance of neonatal differential OTU for the differential serum metabolites. The results indicate Acinetobacter significantly contributes to the differences in the adrenocorticotropic hormone (ACTH) and glucose levels due to HS (P < 0.05). Further, Stenotrophomonas is the most important variable for Cholesterol, low-density lipoprotein (LDL), diamine oxidase (DAO), blood urea nitrogen (BUN) and 5-hydroxytryptamine (5-HT) (P < 0.10). Overall, our data provides evidence for the maternal HS in establishing the neonatal microbiota via affecting maternal transmission, which in turn affects the maintenance of metabolic health.

Size Dependence of the Integral Melting Enthalpy and Entropy of Nanoparticles.

Precise thermodynamic relations to describe the size-dependent integral melting enthalpy and entropy of nanoparticles were deduced by virtue of designing a thermochemical cycle. The differences between integral and differential melting enthalpy and integral and differential melting entropy of nanoparticles were discussed. Nano-Sn of different sizes was prepared by means of chemical reduction, and differential scanning calorimetry (DSC) was utilized to obtain the melting temperature, melting enthalpy, and melting entropy. The experimental results agree with the theoretical predictions and literature results, demonstrating that the melting temperature, enthalpy, and entropy decrease with decreasing particle size and linearly vary with the reciprocal of particle size within the experimental size range. The variations of melting enthalpy and entropy with particle size mainly depend on the molar surface area, the interfacial tension, and the temperature coefficient of interfacial tension. These findings offer a better understanding of the effect of particle size on the melting thermodynamic behaviors of nanoparticles at different melting stages.

Heat stress affects fecal microbial and metabolic alterations of primiparous sows during late gestation.

BACKGROUND: Heat stress (HS) jeopardizes intestinal barrier functions and augments intestinal permeability in pigs. However, whether HS-induced maternal microbial and metabolic changes in primiparous sows during late gestation remains elusive. We present here, a study investigating the fecal microbial and metabolic responses in late gestational primiparous sows when exposed to HS. METHODS: Twelve first-parity Landrace × Large White F1 sows were randomly assigned into two environmental treatments including the thermoneutral (TN) (18-22 °C; n = 6) and HS (28-32 °C; n = 6) conditions. Both treatments were applied from 85 d of gestation to farrowing. The serum and feces samples were collected on d 107 of gestation, for analyses including intestinal integrity biomarkers, high-throughput sequencing metagenomics, short-chain fatty acid (SCFA) profiles and nontargeted metabolomics. RESULTS: Our results show that HS group has higher serum Heat shock protein 70 (HSP70), lipopolysaccharide (LPS) and lipopolysaccharide-binding protein (LBP) levels. The gut microbial community can be altered upon HS by using ß-diversity and taxon-based analysis. In particular, the relative abundance of genera and operational taxonomic units (OTUs) related to Clostridiales and Halomonas are higher in HS group, the relative abundance of genera and OTUs related to Bacteroidales and Streptococcus, however, are lower in HS group. Results of metabolic analysis reveal that HS lowers the concentrations of propionate, butyrate, total SCFA, succinate, fumarate, malate, lactate, aspartate, ethanolamine, ß-alanine and niacin, whereas that of fructose and azelaic acid are higher in HS group. These metabolites mainly affect propanoate metabolism, alanine, aspartate and glutamate metabolism, phenylalanine metabolism, ß-alanine metabolism, pantothenate and CoA biosynthesis, tricarboxylic acid cycle (TCA) and nicotinate and nicotinamide metabolism. Additionally, correlation analysis between significant microbes and metabolites indicated that the HS-induced microbiota shift is likely the cause of changes of intestinal metabolism. CONCLUSIONS: Taken together, we reveal characteristic structural and metabolic changes in maternal gut microbiota as a result of late gestational HS, which could potentially provide the basis for further study on offspring gut microbiota and immune programming.

Size-dependent melting thermodynamics of nanorods in theory and experiment.

Compared with other morphological nanomaterials, nanorods have many unique properties that are closely related to their thermal stability. However, current studies on melting thermodynamic theory of nanorods are still not perfect, and the mechanism and the quantitative regularities of the effect of size of nanorods on melting thermodynamics still remain unclear. Herein, we proposed a melting model of nanorods, derived the thermodynamic relations (free of any adjustable parameters) between the melting temperature, melting enthalpy, and melting entropy, respectively, and the radius of nanorods, and discussed the mechanism of the effect of nanorods and the size dependences of melting thermodynamic properties. Experimentally, taking the melting of Se nanorods as an experimental system, Se nanorods with different diameters were prepared by a Na2SeSO3 disproportionation method, and then the melting temperature and melting thermodynamic properties were determined by differential scanning calorimetry. The effects of the diameter of Se nanorods on the melting temperature and the melting thermodynamic properties were obtained. The experimental results are consistent with the theoretical relations. Both theoretical and experimental results demonstrate that the radius and length of nanorods have significant effects on the melting temperature and the melting thermodynamic properties; for nanorods with a large aspect ratio, the main factors of influence are interfacial tension and radius. Compared with spherical nanoparticles with the same radius, the reduced values of the melting temperature and the thermodynamic properties of nanorods are just half of those corresponding to spherical nanoparticles; the melting temperature, the melting enthalpy, and the melting entropy decrease with the decrease in the radius, and when the radius exceeds 10 nm, these physical quantities are all linearly related to the reciprocal of the radius. The theory can describe the quantitative size-dependent melting thermodynamic properties of nanorods, explain and predict the melting behaviors of nanorods.

Size and shape dependences of the adsorption kinetics of malachite green on nano-MgO: a theoretical and experimental study.

Compared with bulk materials, there is a considerable difference in the adsorption kinetics of nanoparticles, which mainly depend on particle size and shape. Herein, by introducing the shape factor, we have derived the relations between the kinetic parameters of adsorption and the particle size of nanoparticles of different shapes. Then, the influence of the regularities and mechanisms of particle size and shape on the kinetic parameters of adsorption were discussed. In the experiment, spherical nano-MgO and cubic nano-MgO of different particle sizes were synthesized via a sol-gel method, the kinetic parameters of the adsorption of malachite green on nano-MgO were determined, and the influence of the regularities of particle size and shape on the adsorption kinetic parameters were obtained. The experimental results show that shape and particle size may significantly influence the kinetic parameters of adsorption. For the adsorption of nano-MgO with the same equivalent particle diameter, compared to spherical shapes, the rate constant of adsorption k for cubic shapes is larger, while the apparent activation energy Ea and the pre-exponential factor A are smaller. For the adsorption of spherical or cubic nano-MgO, k increases with decreasing particle size, while Ea and A decrease, and there exist good linear relationships between ln k, Ea, ln A and the reciprocal of particle size. The experimental results are well in agreement with the theoretical relations. Furthermore, k is influenced by the shape factor, Ea by the shape factor and the specific surface enthalpy, and A by the shape factor and the temperature coefficient of surface tension. The kinetic theory of adsorption can quantitatively describe the influence of the regularities and mechanisms of particle size and shape on the adsorption kinetics of nanoparticles and provide significant guidance for the research and the application of nano-adsorptions in the related fields.

A controlled heat stress during late gestation affects thermoregulation, productive performance, and metabolite profiles of primiparous sow.

Heat stress (HS) alters metabolic parameters and reduces productive performance in lactating sows. However, the impact of HS on metabolomic profiles of sows during late gestation is not fully understood. We present here, a study investigating the productive performance and metabolic responses in sows when exposed to HS during late gestation. Twelve first-parity Landrace × Large White F1 sows were randomly assigned into two environmental treatments including the thermoneutral (TN) (18-22 °C; n = 6) and HS (28-32 °C; n = 6) conditions from 85 d of gestation until farrowing. Rectal temperature (RT), respiration rates (RR), and surface temperature (ST) were measured every 4 h from 0800 h to 2000 h during the 2nd week. Farrowing and litter Data, as well as duration of eating, were monitored to assess sows' productive performance. Blood biochemical parameters and urinary metabolomic profiles were measured on d107 of gestation to analyze the host metabolic responses. Our results show that HS increased RT, RR, and ST (P < 0.0001). Duration of parturition was prolonged during the delivery in HS group (P < 0.05). Piglet body weight (BW) at d 10 and weaning were reduced by 18% and 17% respectively due to maternal HS (P < 0.001). Duration of eating increased as a result of HS (P < 0.001), consistent with the significant changes observed in serum ghrelin (P < 0.05). Moreover, serum ACTH, cortisol, insulin, creatinine, and BUN saw increase as well (P < 0.05). Plasma NEFA were elevated by HS (P < 0.001). Additionally, HS elevated (VIP>1, log2fold change>0.585, and P < 0.05) the relative concentrations of 5-aminovaleric acid, ß-alanine, cysteine, isoleucine, glyceric acid, erythronic acid, mannitol, erythritol, 2-methyl-1,3-butanediol, and pantothenic acid in urine. These ten metabolites mainly affected the pantothenate and CoA biosynthesis, ß-alanine metabolism, and glycerolipid metabolism in pregnant sows. In summary, our study suggests that the controlled HS during late gestation elevates thermal responses, reduces productive performance, and more importantly, enhances the catabolism of lipid and protein of first-parity pregnant sow.

Suhuai suckling piglet hindgut microbiome-metabolome responses to different dietary copper levels.

Unabsorbed copper accumulates in the hindgut of pigs that consume high levels of dietary copper, which enhances the coselection of antibiotic-resistant bacteria and is considered detrimental to the environment and to porcine health. In our study, a combination of 16S rRNA pyrosequencing and nontargeted metabolomics was used to investigate the microbiome-metabolome responses to dietary copper levels in the hindgut of suckling piglets. The results showed that the dietary copper level affected the abundance of several Clostridia genera and that the relative abundance of butyrate-producing bacteria, such as Coprococcus, Roseburia, and Acidaminococcus, was reduced in the 300 mg kg-1 (high) Cu group. Metabolomic analysis revealed that dietary copper levels affected protein and carbohydrate metabolites, protein biosynthesis, the urea cycle, galactose metabolism, gluconeogenesis, and amino acid metabolism (including the metabolism of arginine, proline, ß-alanine, phenylalanine, tyrosine, and methionine). Furthermore, Pearson's correlation analysis showed that the abundance levels of Coprococcus (family Lachnospiraceae) and operational taxonomic unit (OTU) 18 (family Ruminococcaceae) were positively correlated with energy metabolism pathways (gluconeogenesis, glycolysis, and the pentose phosphate pathway). The abundance of Streptococcus was negatively correlated with amino acid metabolism pathways (protein biosynthesis, glycine, serine, threonine, methionine, phenylalanine, and tyrosine metabolism), and OTU583 and OTU1067 (family Rikenellaceae) were positively correlated with amino acid metabolism pathways. These results suggest that the copper levels consumed by LC (low-copper group) versus HC (high-copper group) animals alter the composition of the gut microbiota and modulate microbial metabolic pathways, which may further affect the health of suckling piglets.

Shape dependence of thermodynamics of adsorption on nanoparticles: a theoretical and experimental study.

Nanomaterials have excellent adsorption performance, which mainly depends on the adsorption thermodynamics that is related to the shape of the nanoparticles that make up the nanomaterial, but the effects of shape on the thermodynamics of adsorption are not fully clear. In this paper, theoretically, the general formulae of adsorption thermodynamic properties for nanoparticles with different shapes and different sizes were derived, and the influencing regularities and mechanisms on adsorption thermodynamic properties were discussed. Experimentally, the influences of the shape and size of nano-CeO2 on the thermodynamics of adsorption were studied in aqueous solution. The experiment results showed that the shape has significant influences on the thermodynamics of adsorption, and the smaller the particle size, the more significant the effects of shape on the thermodynamics. For the adsorption of nano-CeO2 with different shapes and the same equivalent particle size, compared with the sphere, the equilibrium constant of adsorption for the octahedron is larger, while the molar Gibbs free energy of adsorption , the molar adsorption enthalpy of adsorption and the molar adsorption entropy of adsorption are smaller. For the adsorption of nano-CeO2 with the same shape, with the decreasing particle size, increases, while , and decrease; and , , and are each linearly related to the reciprocal of particle size. The experimental results are consistent with the theoretical relations. The theories can quantitatively describe the adsorption behavior on nanoparticles, explain the regularities and mechanisms of influence of shape, and provide guidance for the research and application of nanoadsorption.

Determination Method and Size Dependence of Interfacial Tension between Nanoparticles and a Solution.

Interfacial tension plays an important role in the processes of preparation, research, and application of nanomaterials. Because the interfacial tension is fairly difficult to be determined by experiments, it is still unclear about the effect of particle size on interfacial tension. In this paper, we proposed a method to determine the interfacial tensions and its temperature coefficients by determining the electrode potential of the nanoparticle electrode. Nano-Au with different radii (from 0.9 to 37.4 nm) in an aqueous solution was taken as a research system; we determined the interfacial tension and its temperature coefficient of the interface and discussed the size dependence. At the same time, we found surprisingly that this method can also be applied to determine the Tolman length and the atomic radius. The results show that the particle size of nano-Au has remarkable influences on the interfacial tension and its temperature coefficient. As the particle size decreases, the interfacial tension and the absolute value of its temperature coefficient increase. With the decrease of radius, the influences of the particle size on the interfacial tension and its temperature coefficient become more significant, whereas the influences can be neglected when the radius exceeds 10 nm. In addition, the results also show that the Tolman length is a negative value, and temperature has little effect on the Tolman length. This research can provide a new method to conveniently and reliably determine the interfacial tension on interfaces between nanoparticles and solutions, the temperature coefficients, the Tolman lengths, and the atomic radii; and the size dependences can provide important references for preparation, research, and application of nanomaterials.

Synthesis of TiO2/Fly Ash Cenospheres by Sol-Gel Method and Their Photacatalytic Activities Under Visible Light.

Fly ash is a solid waste discharged from thermal power plant. Specific surface area of floating fly ash cenospheres (FACs) would increase after it was modified. The photocatalytic composite of TiO2/FACs was successfully synthesized by sol-gel method using the carrier of modified FACs and tetrabutyl titanate as starting materials. The different influence factors on the photocatalytic performance of TiO2/FACs composites were characterized through SEM, EDS, XRD, UV-vis DRS and BET surface measurements. The UV-vis DRS spectra revealed that the absorption edge of TiO2 is 387 nm while that of TiO2/FACs photocatalysts red-shifts to 500 nm. Photocatalytic activity of TiO2/FACs was evaluated by the photocatalytic depigmentation of methyl orange solution (MO, 20 mg L-1, pH = 6.3) under visible light irradiation. It was found that the specific surface area, surface roughness and activity of FACs were increased by NaOH solution activation. The degradation rate of MO reaches 52% in 180 min under the visible light illumination. But too much FACs could decrease its photocatalytic activity and degradation rate. And the recovery test indicated that TiO2/FACs photocatalyst was rather stable, easy to recover from the treated wastewater.