Efficient and selective dehydrogenation of formic acid is a key challenge for a fuel‐cell‐based hydrogen economy. Though the development of heterogeneous catalysts has received much progress, their ...catalytic activity remains insufficient. Moreover, the design principle of such catalysts are still unclear. Here, experimental and theoretical studies on a series of mono‐/bi‐metallic nanoparticles supported on a NH2‐N‐rGO substrate are combined for formic acid dehydrogenation where the surface energy of a metal is taken as a relevant indicator for the adsorption ability of the catalyst for guiding catalyst design. The AuPd/NH2‐N‐rGO catalyst shows record catalytic activity by reducing the energy barrier of rate controlling steps of formate adsorption and hydrogen desorption. The obtained excellent results both in experiments and simulations could be extended to other important systems, providing a general guideline to design more efficient catalysts.
A AuPd/NH2‐N‐rGO catalyst shows supreme catalytic performance for the decomposition of formic acid at room temperature, with a turnover frequency (TOF) of 4445.6 h−1. Developments in the experiments and simulations of high‐performance catalysts may promote the practical application of formic acid as a promising hydrogen storage material.
A vaccine to protect against COVID-19 is urgently needed. We aimed to assess the safety, tolerability, and immunogenicity of a recombinant adenovirus type-5 (Ad5) vectored COVID-19 vaccine expressing ...the spike glycoprotein of a severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) strain.
We did a dose-escalation, single-centre, open-label, non-randomised, phase 1 trial of an Ad5 vectored COVID-19 vaccine in Wuhan, China. Healthy adults aged between 18 and 60 years were sequentially enrolled and allocated to one of three dose groups (5 × 1010, 1 × 1011, and 1·5 × 1011 viral particles) to receive an intramuscular injection of vaccine. The primary outcome was adverse events in the 7 days post-vaccination. Safety was assessed over 28 days post-vaccination. Specific antibodies were measured with ELISA, and the neutralising antibody responses induced by vaccination were detected with SARS-CoV-2 virus neutralisation and pseudovirus neutralisation tests. T-cell responses were assessed by enzyme-linked immunospot and flow-cytometry assays. This study is registered with ClinicalTrials.gov, NCT04313127.
Between March 16 and March 27, 2020, we screened 195 individuals for eligibility. Of them, 108 participants (51% male, 49% female; mean age 36·3 years) were recruited and received the low dose (n=36), middle dose (n=36), or high dose (n=36) of the vaccine. All enrolled participants were included in the analysis. At least one adverse reaction within the first 7 days after the vaccination was reported in 30 (83%) participants in the low dose group, 30 (83%) participants in the middle dose group, and 27 (75%) participants in the high dose group. The most common injection site adverse reaction was pain, which was reported in 58 (54%) vaccine recipients, and the most commonly reported systematic adverse reactions were fever (50 46%), fatigue (47 44%), headache (42 39%), and muscle pain (18 17%. Most adverse reactions that were reported in all dose groups were mild or moderate in severity. No serious adverse event was noted within 28 days post-vaccination. ELISA antibodies and neutralising antibodies increased significantly at day 14, and peaked 28 days post-vaccination. Specific T-cell response peaked at day 14 post-vaccination.
The Ad5 vectored COVID-19 vaccine is tolerable and immunogenic at 28 days post-vaccination. Humoral responses against SARS-CoV-2 peaked at day 28 post-vaccination in healthy adults, and rapid specific T-cell responses were noted from day 14 post-vaccination. Our findings suggest that the Ad5 vectored COVID-19 vaccine warrants further investigation.
National Key R&D Program of China, National Science and Technology Major Project, and CanSino Biologics.
This is the first randomised controlled trial for assessment of the immunogenicity and safety of a candidate non-replicating adenovirus type-5 (Ad5)-vectored COVID-19 vaccine, aiming to determine an ...appropriate dose of the candidate vaccine for an efficacy study.
This randomised, double-blind, placebo-controlled, phase 2 trial of the Ad5-vectored COVID-19 vaccine was done in a single centre in Wuhan, China. Healthy adults aged 18 years or older, who were HIV-negative and previous severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection-free, were eligible to participate and were randomly assigned to receive the vaccine at a dose of 1 × 1011 viral particles per mL or 5 × 1010 viral particles per mL, or placebo. Investigators allocated participants at a ratio of 2:1:1 to receive a single injection intramuscularly in the arm. The randomisation list (block size 4) was generated by an independent statistician. Participants, investigators, and staff undertaking laboratory analyses were masked to group allocation. The primary endpoints for immunogenicity were the geometric mean titres (GMTs) of specific ELISA antibody responses to the receptor binding domain (RBD) and neutralising antibody responses at day 28. The primary endpoint for safety evaluation was the incidence of adverse reactions within 14 days. All recruited participants who received at least one dose were included in the primary and safety analyses. This study is registered with ClinicalTrials.gov, NCT04341389.
603 volunteers were recruited and screened for eligibility between April 11 and 16, 2020. 508 eligible participants (50% male; mean age 39·7 years, SD 12·5) consented to participate in the trial and were randomly assigned to receive the vaccine (1 × 1011 viral particles n=253; 5 × 1010 viral particles n=129) or placebo (n=126). In the 1 × 1011 and 5 × 1010 viral particles dose groups, the RBD-specific ELISA antibodies peaked at 656·5 (95% CI 575·2–749·2) and 571·0 (467·6–697·3), with seroconversion rates at 96% (95% CI 93–98) and 97% (92–99), respectively, at day 28. Both doses of the vaccine induced significant neutralising antibody responses to live SARS-CoV-2, with GMTs of 19·5 (95% CI 16·8–22·7) and 18·3 (14·4–23·3) in participants receiving 1 × 1011 and 5 × 1010 viral particles, respectively. Specific interferon γ enzyme-linked immunospot assay responses post vaccination were observed in 227 (90%, 95% CI 85–93) of 253 and 113 (88%, 81–92) of 129 participants in the 1 × 1011 and 5 × 1010 viral particles dose groups, respectively. Solicited adverse reactions were reported by 183 (72%) of 253 and 96 (74%) of 129 participants in the 1 × 1011 and 5 × 1010 viral particles dose groups, respectively. Severe adverse reactions were reported by 24 (9%) participants in the 1 × 1011 viral particles dose group and one (1%) participant in the 5 × 1010 viral particles dose group. No serious adverse reactions were documented.
The Ad5-vectored COVID-19 vaccine at 5 × 1010 viral particles is safe, and induced significant immune responses in the majority of recipients after a single immunisation.
National Key R&D Programme of China, National Science and Technology Major Project, and CanSino Biologics.
In situ forming gel polymer electrolyte (GPE) is one of the most feasible ways to improve the safety and cycle performances of lithium metal batteries with high energy density. However, most of the ...in situ formed GPEs are not compatible with high‐voltage cathode materials. Here, this work provides a novel strategy to in situ form GPE based on the mechanism of Ritter reaction. The Ritter reaction in liquid electrolyte has the advantage of appropriate reaction temperature and no additional additives. The polymer chains are cross‐linked by amide groups with the formation of GPE with superior electrochemical properties. The GPE has high ionic conductivity (1.84 mS cm−1), wide electrochemical stability window (>5.25 V) and high lithium ion transference number (≈0.78), compatible with high‐voltage cathode materials. The Li|LiNi0.6Co0.2Mn0.2O2 batteries with in situ formed GPE show excellent long‐term cycle stability (93.4%, 300 cycles). The density functional theory calculation and X‐ray photoelectron spectroscopy results verify that the amide and nitrile groups are beneficial for stabilizing cathode structure and promoting uniform Li deposition on Li anode. Furthermore, the in situ formed GPE exhibits excellent electrochemical performance in Graphite|LiMn2O4 and Graphite|LiNi0.5Co0.2Mn0.3O2 pouch batteries. This approach is adaptable to current battery technologies, which will be sure to promote the development of high energy‐density lithium‐ion batteries.
Gel polymer electrolyte with high ionic conductivity, wide electrochemical stability window and high lithium‐ion transference number is developed. It can improve the cycle performance of lithium metal batteries by stabilizing cathode structure and promoting uniform Li deposition, which is also applicable to current battery technologies.
Permeability controls fluid flow in fault zones and is a proxy for rock damage after an earthquake. We used the tidal response of water level in a deep borehole to track permeability for 18 months in ...the damage zone of the causative fault of the 2008 moment magnitude 7.9 Wenchuan earthquake. The unusually high measured hydraulic diffusivity of 2.4 x 10⁻² square meters per second implies a major role for water circulation in the fault zone. For most of the observation period, the permeability decreased rapidly as the fault healed. The trend was interrupted by abrupt permeability increases attributable to shaking from remote earthquakes. These direct measurements of the fault zone reveal a process of punctuated recovery as healing and damage interact in the aftermath of a major earthquake.
C-Glycosides, a special type of glycoside, are frequently distributed in many kinds of medicinal plants, such as puerarin and mangiferin, showing various and significant bioactivities. C-Glycosides ...are usually characterized by the C–C bond that forms between the anomeric carbon of sugar moieties and the carbon atom of aglycon, which is usually resistant against acidic hydrolysis and enzymatic treatments. Interestingly, C-glycosides could be cleaved by several intestinal bacteria, but whether the enzymatic cleavage of C–C glycosidic bond is reduction or hydrolysis has been controversial; furthermore, whether existence of a “C-glycosidase” directly catalyzing the cleavage is not clear. Here we review research advances about the discovery and mechanism of intestinal bacteria in enzymatic cleavage of C–C glycosidic bond with an emphasis on the identification of enzymes manipulation the deglycosylation. Finally, we give a brief conclusion about the mechanism of C-glycoside deglycosylation and perspectives for future study in this field.
Some studies have shown that gut microbiota along with its metabolites is closely associated with diabetic mellitus (DM). In this study we explored the relationship between gut microbiota and kidney ...injuries of early diabetic nephropathy (DN) and its underlying mechanisms. Male SD rats were intraperitoneally injected with streptozotocin to induce DM. DM rats were orally administered compound broad-spectrum antibiotics for 8 weeks. After the rats were sacrificed, their blood, urine, feces, and renal tissues were harvested for analyses. We found that compared with the control rats, DM rats had abnormal intestinal microflora, increased plasma acetate levels, increased proteinuria, thickened glomerular basement membrane, and podocyte foot process effacement in the kidneys. Furthermore, the protein levels of angiotensin II, angiotensin-converting enzyme, and angiotensin II type 1 receptor in the kidneys of DM rats were significantly increased. Administration of broad-spectrum antibiotics in DM rats not only completely killed most intestinal microflora, but also significantly lowered the plasma acetate levels, inhibited intrarenal RAS activation, and attenuated kidney damage. Finally, we showed that plasma acetate levels were positively correlated with intrarenal angiotensin II protein expression (r = 0.969, P < 0.001). In conclusion, excessive acetate produced by disturbed gut microbiota might be involved in the kidney injuries of early DN through activating intrarenal RAS.
Objectives
Cholestasis is a critical risk factor for severe hepatic disease or cirrhosis. The anti‐inflammatory effect of Paeonia lactiflora Pall. (PLP), named Chishao in traditional Chinese medicine ...(TCM), on alpha‐naphthylisothiocyanate (ANIT)‐induced cholestasis model was tried to be elucidated in this research.
Methods
Therapeutic effect indices on hepatic function, including ALT, AST, TBIL, DBIL, ALP, TBA and γ‐GT, were measured. To further investigate the protective mechanism of PLP, the mRNA and protein expression levels of NF‐κB‐NLRP3 inflammasome pathway were detected.
Results
Our results showed that compared with the model group, PLP could significantly reduce the increased serum indices such as ALT, AST, TBIL, DBIL, ALP, TBA and γ‐GT induced by ANIT in a dose‐dependent way. Moreover, we found that PLP downregulated the mRNA expression levels including IKK, p65, NLRP3, caspase‐1 and IL‐1β, especially at the large dose. Furthermore, PLP also significantly inhibited NF‐κB‐NLRP3 inflammasome pathway by decreasing the protein levels of p65, p‐p65, p‐IKK, NLRP3, caspase‐1 and IL‐1β.
Conclusions
The results indicated that PLP could ameliorate ANIT‐induced cholestasis in rats and the anti‐inflammatory effect of PLP might be related to regulating NF‐κB‐NLRP3 inflammasome pathway. This study will provide scientific evidence for PLP as a potential drug candidate for cholestasis.
The aqueous solution-based zinc-ion hybrid supercapacitors (ZHSCs) have attracted immense attention as they are characterized by high power and energy densities. Electrode materials with high ...performance should be developed for ZHSCs to resolve power imbalances between capacitor- and battery-type electrode materials. To address this issue, Nb
2
O
5
microspheres (with the structure like sweet dumplings with exposed stuffing) were produced following a hydrothermal process which was followed by a high-temperature calcination process. The specific capacity of the as-synthesized Nb
2
O
5
microspheres was up to 324 F·g
–1
when the current density was 0.1 A·g
–1
, and the long-term capacity retention was 85% at the end of 5000 cycles. The results revealed that the nanospheres could be used as battery-type electrode materials for the fabrication of ZHSCs. Nb
2
O
5
//AC ZHSCs were fabricated with Nb
2
O
5
microspheres as the negative electrode materials, and activated carbon (AC) was used as the positive electrode material. As a result, a specific capacity of 108 F·g
–1
was achieved when the current density was 0.1 A·g
–1
. The power density was high (8020 W·kg
–1
) at 28 Wh·kg
–1
, and the energy density was high (60 Wh·kg
–1
) at 100 W·kg
–1
. The structurally novel Nb
2
O
5
microspheres can be potentially used for the development of the next-generation ZHSCs that exhibit excellent performance.
Graphical abstract
Scheme 1. Schematic representation of the HIPPEs stabilized solely by SPI-PA complexes. SPI-PA complexes -stabilized HIPPEs with φ = 0.8.
Display omitted
•A green facile method to construct SPI-PA ...complexes as stabilizer was reported.•A HIPPEs stabilized by SPI-PA complexes was successfully constructed.•The HIPPEs have outstanding emulsifying and antioxidative properties.
Protein-based high internal phase Pickering emulsions (HIPPEs) feature numerous multi-functionalities and widespread applications. However, the direct use of native proteins for the constructions of HIPPEs is limited since it is fragile under various conditions. Here, cold plasma was used to modify soy protein isolates (SPI) to improve their surficial properties. Meanwhile, proanthocyanidins (PA) were applied to interact with cold plasma-treated SPI to form complex. Furthermore, the well-prepared SPI-PA complex was used to construct novel HIPPEs. Results showed cold plasma treatment significantly improved the functionalities of SPI, which were confirmed by surface hydrophobicity (H0 ＜ 500), sulfhydryl (SH) groups and spectral analysis. Further, the emulsification and oxidation resistance of cold plasma treated SPI were enhanced after forming complex with PA. Soybean oils can be stabilized by SPI-PA complexes to form HIPPEs with a lipid oxidation inhibition rate of ＞ 65%, creaming index (CI) ＞ 80%, excellent rheological properties and better stability compared with conventional emulsion systems. Overall, this SPI-PA complexes provides a unique approach to improve the emulsification and oxidation resistance to engineer HIPPEs with versatile applications.
PDF
