Exploring efficient and cost-effective catalysts to replace precious metal catalysts, such as Pt, for electrocatalytic oxygen reduction reaction (ORR) and hydrogen evolution reaction (HER) holds ...great promise for renewable energy technologies. Herein, we prepare a type of Co catalyst with single-atomic Co sites embedded in hierarchically ordered porous N-doped carbon (Co-SAS/HOPNC) through a facile dual-template cooperative pyrolysis approach. The desirable combination of highly dispersed isolated atomic Co-N₄ active sites, large surface area, high porosity, and good conductivity gives rise to an excellent catalytic performance. The catalyst exhibits outstanding performance for ORR in alkaline medium with a half-wave potential (E
1/2) of 0.892 V, which is 53 mV more positive than that of Pt/C, as well as a high tolerance of methanol and great stability. The catalyst also shows a remarkable catalytic performance for HER with distinctly high turnover frequencies of 0.41 and 3.8 s−1 at an overpotential of 100 and 200 mV, respectively, together with a long-term durability in acidic condition. Experiments and density functional theory (DFT) calculations reveal that the atomically isolated single Co sites and the structural advantages of the unique 3D hierarchical porous architecture synergistically contribute to the high catalytic activity.
This study aimed to determine the effects of chlorogenic acid (CGA) on the growth performance, intestinal health, immune response, and mitochondrial DNA (mtDNA)–cyclic GMP–AMP synthase ...(cGAS)–stimulator of interferon genes (STING) signaling pathway in broilers under necrotic enteritis (NE) challenge. The 180 one-day-old male Cobb 500 broilers with similar body weight of 44.59 ± 1.39 g were randomly allocated into 3 groups. The groups were control diet (Control group), control diet + NE challenge (NE group), and control diet + 500 mg/kg CGA + NE challenge (NE + CGA group), with 6 replicates per treatment. All broilers except the Control group were given sporulated coccidian oocysts (d 14) and Clostridium perfringens (d 19–21) by oral gavage. Our findings showed that CGA improved the growth performance and intestinal morphology in broilers under NE challenge. CGA supplementation elevated the barrier function in broilers under NE challenge, which reflected in the decreased serum concentrations of D-lactate and diamine oxidase, and upregulated jejunal protein expression of occludin. CGA supplementation also improved the immune function, which reflected in the increased concentrations and gene expressions of anti-inflammatory factors, and decreased concentrations and gene expressions of proinflammatory factors. CGA supplementation further enhanced intestinal cell proliferation and differentiation, which manifested in the increased number of goblet cells and positive cells of proliferating cell nuclear antigen on d 28 and 42. Furthermore, CGA supplementation decreased the mtDNA (d 42) and mitochondrial reactive oxygen species levels (d 28 and 42), and increased the mitochondrial membrane potential (d 42) and mitochondrial complex I (d 28 and 42) or III (d 28) activity. Broilers challenged with NE had upregulated jejunal protein expressions of cGAS, phospho-TANK-binding kinase 1, and phospho-interferon regulatory factor 7 compared with the Control group, which were downregulated after CGA supplementation. In conclusion, dietary supplementation CGA could protect against intestinal inflammation and injury by reducing the leakage of mtDNA and inactivating the cGAS–STING signaling pathway in broilers under NE challenge.
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In order to investigate the chronic effects of basic amino acids (BAA) on β-cell metabolism and insulin secretion, INS-1 β-cells were randomly assigned to cultures in standard medium (Con), standard ...medium plus 10 mM L-Arginine (Arg), standard medium plus 10 mM L-Histidine (His) or standard medium plus 10 mM L-Lysine (Lys) for 24 h. Results showed that insulin secretion was decreased by the Arg treatment but was increased by the His treatment relative to the Con group (p < 0.05). Higher BAA concentrations reduced the high glucose-stimulated insulin secretions (p < 0.001), but only Lys treatment increased the intracellular insulin content than that in the Con group (p < 0.05). Compared with Arg and Lys, the His treatment increased the mitochondrial key enzyme gene expressions including Cs, mt-Atp6, mt-Nd4l and Ogdh, and caused a greater change in the metabolites profiling (p < 0.05). The most significant pathways affected by Arg, His and Lys were arginine and proline metabolism, aminoacyl-tRNA biosynthesis and pyrimidine metabolism, respectively. Regression analysis screened 7 genes and 9 metabolites associated with insulin releases during BAA stimulations (p < 0.05). Together, different BAAs exerted dissimilar effects on β-cell metabolism and insulin outputs.
Three-dimensionally ordered mesoporous carbon sphere array (OMCS)-supported Pt nanoparticles (Pt/OMCS) were synthesized and studied as electrocatalysts for the methanol oxidation reaction (MOR) and ...oxygen reduction reaction (ORR). In the Pt/OMCS, the Pt particles with a mean size of ∼1.6 nm are homogeneously dispersed on the mesopore walls of the carbon spheres. The Pt/OMCS catalyst exhibits smaller Pt particle size, greater Pt dispersion, larger specific electrochemically active surface area (ECSA), higher activity for MOR and ORR, and better electrocatalytic stability than the carbon black (Vulcan XC-72R)-supported Pt and commercial Pt/C catalysts.
On‐again, off‐again personality: Superhydrophobic conducting polypyrrole (PPy) films are synthesized through a facile electrochemical process. The PPy films exhibit an extended porous structure with ...both coarse‐ and fine‐scale roughness (see image). By controlling the electrical potential, PPy films can be switched between the oxidized state and the neutral state, resulting in reversibly switchable superhydrophobic and superhydrophilic properties.
Milk protein (MP) synthesis in the mammary gland of dairy cows is a complex biological process. As the substrates for protein synthesis, amino acids (AAs) are the most important nutrients for milk ...synthesis. Free AAs (FAAs) are the main precursors of MP synthesis, and their supplies are supplemented by peptide-bound AAs (PBAAs) in the blood. Utilization of AAs in the mammary gland of dairy cows has attracted the great interest of researchers because of the goal of increasing MP yield. Supplying sufficient and balanced AAs is critical to improve MP concentration and yield in dairy cows. Great progress has been made in understanding limiting AAs and their requirements for MP synthesis in dairy cows. This review focuses on the effects of FAA and PBAA supply on MP synthesis and their underlying mechanisms. Advances in our knowledge in the field can help us to develop more accurate models to predict dietary protein requirements for dairy cows MP synthesis, which will ultimately improve the nitrogen utilization efficiency and lactation performance of dairy cows.
The 3D ordered macro-/mesoporous (3DOM/m) NixCo100-x alloys with abundant active sites and fast mass transfer rate were fabricated by a dual-templating technique. The catalysts present ...high-performance for both HER and OER, and can be applied for overall water splitting in alkaline electrolyte.
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Electrochemical water splitting is a facile and effective route to generate pure hydrogen and oxygen. However, the sluggish kinetics of hydrogen evolution reaction (HER) and especially oxygen evolution reaction (OER) hinder the water splitting efficiency. Meanwhile, the high-cost of noble-metal catalysts limit their actual application. It is thus highly urgent to exploit an economical and earth-abundant bifunctional HER and OER electrocatalyst to simplify procedure and reduce cost. Herein, we synthesize the three-dimensionally ordered macro-/mesoporous (3DOM/m) NixCo100-x alloys with distinctive structure and large surface area via a dual-templating technique. Among them, the 3DOM/m Ni61Co39 shows the lowest overpotentials of 121 mV and 241 mV at 10 mA/cm2 for HER and OER, respectively. Furthermore, when employed for water splitting, the Ni61Co39 only requires 1.60 V to approach 10 mA/cm2 and presents excellent stability. These encouraging performances of the Ni61Co39 render it a promising bifunctional catalyst for overall water splitting.
Previous studies have demonstrated that diabetes is often accompanied with lower magnesium status. However, practical details regarding the influences of magnesium intervention on hyperglycemia, ...hypercholesterolemia, and hypertension in type 2 diabetes (T2D) need to be further investigated.
Web of Science, ScienceDirect, and PubMed were searched for relevant literatures published through April 30, 2022, and high-quality data were pooled to evaluate the effects of magnesium supplementation on glycemic, circulating lipids, and blood pressure control in T2D, and to explore the associated practical details.
Pooled analyses of 24 randomized controlled trials with 1,325 T2D individuals revealed that subjects who received magnesium supplementation had statistically significant reductions in fasting plasma glucose, glycated hemoglobin, systolic blood pressure and diastolic blood pressure, with WMD values of -0.20 mM (95% CI: -0.30, -0.09), -0.22% (95% CI: -0.41, -0.03), -7.69 mmHg (95% CI: -11.71, -3.66) and -2.71 mmHg (95% CI: -4.02, -1.40), respectively. Detailed subgroup analyses demonstrated that health status of participants including age, body mass index, country, duration of disease, baseline magnesium level and baseline glycemic control condition as well as magnesium formulation, dosage and duration of intervention influenced the effects of magnesium addition. Dose-effect analysis showed that 279 mg/d for 116 d, 429 mg/d for 88 d and 300 mg/d for 120 d are the average optimal dosages and durations for improving glycemic, circulating lipids, and blood pressure controls, respectively.
Our findings provide clinically relevant information on the adjuvant therapy of magnesium for improving hyperglycemia, hypercholesterolemia, and hypertension in T2D.
A solution-phase synthesis method was studied to prepare carbon supported Pt-Co alloy catalysts. The organic precursors of Pt acetylacetonate and Co acetylacetonate were reduced in a high boiling ...point solvent of octyl ether in the presence of oleic acid (OAc) and oleylamine (OAm) to produce fine Pt-Co nanoparticles, which were subsequently deposited on carbon support to obtain Pt-Co/C catalysts. Thermogravimetric analysis suggests that the stabilizers (OAc and OAm) can be removed by copious ethanol washing and subsequent moderate temperature heat-treatment (250
°C, under Argon atmosphere). X-ray diffraction patterns indicate that the average particle size is around 2.3
nm, and the lattice parameter is 3.868
Å for the heat-treated Pt-Co/C (40
wt%). Transmission electron microscopy images show very small Pt-Co alloy nanoparticles homogeneously dispersed on the carbon support with a particle size distribution of 2–4
nm for all Pt-Co/C samples. The elements composition of Pt and Co in the final Pt-Co/C catalyst can be well controlled, as evidenced by inductively coupled plasma atomic emission spectroscopy and energy dispersive spectroscopy analyses. Proton exchange membrane fuel cell tests show the heat-treated Pt-Co/C cathode catalyst has higher mass activity of oxygen reduction reaction than Pt/C at an operation voltage of 0.9
V, this can be attributed to its smaller particle size and reduced lattice parameter.
Application of high-throughput sequencing and screening help to detect the transcriptional and metabolic discrepancies in organs provided with various levels of nutrients. The influences of ...individual essential amino acid (EAA) administration on transcriptomic and metabolomic profilings of bovine mammary epithelial cells (BMECs) were systematically investigated. A RNA sequencing and liquid chromatography-tandem mass spectrometry generated a comprehensive comparison of transcriptomics, non-targeted metabolomics and targeted amino acids profilings of BMECs with individual EAA stimulation by turn. The sequencing data and raw LC-MS/MS data of samples were presented in the databases of Gene Expression Omnibus, MetaboLights and Figshare for efficient reuse, including exploring the divergences in metabolisms between different EAAs and screening valuable genes and metabolites regulating casein synthesis.
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