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Background: SARS-CoV-2 has caused millions of deaths, and, since Aug 11, 2020, 20 intramuscular COVID-19 vaccines have been approved for use. We aimed to evaluate the safety and immunogenicity of an aerosolised adenovirus type-5 vector-based COVID-19 vaccine (Ad5-nCoV) in adults without COVID-19 from China.Method: This was a randomised, single-centre, open-label, phase 1 trial done in Zhongnan Hospital (Wuhan, China), to evaluate the safety and immunogenicity of the Ad5-nCoV vaccine by aerosol inhalation in adults (≥18 years) seronegative for SARS-CoV-2. Breastfeeding or pregnant women and people with major chronic illnesses or history of allergies were excluded. Participants were enrolled and randomly assigned (1:1:1:1:1) into five groups to be vaccinated via intramuscular injection, aerosol inhalation, or both. Randomisation was stratified by sex and age (18-55 years or ≥56 years) using computer-generated randomisation sequences (block sizes of five). Only laboratory staff were masked to group assignment. The participants in the two aerosol groups received an initial high dose (2 × 1010 viral particles; HDmu group) or low dose (1 × 1010 viral particles; LDmu group) of Ad5-nCoV vaccine on day 0, followed by a booster on day 28. The mixed vaccination group received an initial intramuscular (5 × 1010 viral particles) vaccine on day 0, followed by an aerosolised booster (2 × 1010 viral particles) vaccine on day 28 (MIX group). The intramuscular groups received one dose (5 × 1010 viral particles; 1Dim group) or two doses (10 × 1010 viral particles; 2Dim group) of Ad5-nCoV on day 0. The primary safety outcome was adverse events 7 days after each vaccination, and the primary immunogenicity outcome was anti-SARS-CoV-2 spike receptor IgG antibody and SARS-CoV-2 neutralising antibody geometric mean titres at day 28 after last vaccination. This trial is registered with ClinicalTrials.gov, number NCT04552366.Findings: Between Sept 28, 2020, and Sept 30, 2020, 230 individuals were screened for inclusion, of whom 130 (56%) participants were enrolled into the trial and randomly assigned into one of the five groups (26 participants per group). Within 7 days after vaccination, adverse events occurred in 18 (69%) in the HDmu group, 19 (73%) in the LDmu group, 19 (73%) in the MIX group, 19 (73%) in the 1Dim group, and 15 (58%) in the 2Dim group. The most common adverse events reported 7 days after the first or booster vaccine were fever (62 [48%] of 130 participants), fatigue (40 [31%] participants), and headache (46 [35%] participants). More adverse events were reported in participants who received intramuscular vaccination, including participants in the MIX group (49 [63%] of 78 participants), than those who received aerosol vaccine (13 [25%] of 52 participants) after the first vaccine vaccination. No serious adverse events were noted within 56 days after the first vaccine. At days 28 after last vaccination, geometric mean titres of SARS-CoV-2 neutralising antibody was 107 (95% CI 47-245) in the HDmu group, 105 (47-232) in the LDmu group, 396 (207-758) in the MIX group, 95 (61-147) in the 1Dim group, and 180 (113-288) in the 2Dim group. The geometric mean concentrations of receptor binding domain-binding IgG was 261 EU/mL (95% CI 121-563) in the HDmu group, 289 EU/mL (138-606) in the LDmu group, 2013 EU/mL (1180-3435) in the MIX group, 915 EU/mL (588-1423) in the 1Dim group, and 1190 EU/mL (776-1824) in the 2Dim group.Interpretation: Aerosolised Ad5-nCoV is well tolerated, and two doses of aerosolised Ad5-nCoV elicited neutralising antibody responses, similar to one dose of intramuscular injection. An aerosolised booster vaccination at 28 days after first intramuscular injection induced strong IgG and neutralising antibody responses. The efficacy and cost-effectiveness of aerosol vaccination should be evaluated in future studies.Funding: National Key Research and Development Programme of China and National Science and Technology Major Project.Translation: For the Chinese translation of the Summary see Supplementary Material. [ABSTRACT FROM AUTHOR]

The Lead-free all-inorganic double perovskite Cs 2 AgBiBr 6 is regarded as an attractive alternative to lead-based organic-inorganic counterparts in perovskite solar cells (PSCs) because of the superb durability, nontoxicity and distinct optical properties. Nevertheless, the power conversion efficiencies (PCEs) of Cs 2 AgBiBr 6 -based cells are significantly limited by both inherent and external defects in Cs 2 AgBiBr 6 films caused by structural/optical features and fabrication processes, respectively. Thus, it is necessary to conduct a review to enhance fundamental knowledge regarding the decisive performance-limiting factors and relevant performance improvement strategies of Cs 2 AgBiBr 6 -based PSCs. Herein, fundamental knowledge of the decisive performance-limiting factors and relevant origins of Cs 2 AgBiBr 6 -based PSCs is presented, including inferior sunlight absorption capability, inferior film quality, high defect amount and unsuitable energy level alignment. On this basis, some distinct strategies to improve the PCEs of Cs 2 AgBiBr 6 -based cells are proposed such as dye sensitization, band gap regulation, interface control, additive engineering and (anti-)solvent design. Finally, the remaining key problems and future research directions of Cs 2 AgBiBr 6 -based PSCs are provided. Our review aims to present important guidance for future research on Cs 2 AgBiBr 6 -based PSCs to break the efficiency record. [Display omitted] • The superiorities of Cs 2 AgBiBr 6 -based PSCs over Pb-based counterparts are illustrated. • The fundamental understanding of the decisive performance-limiting factors is presented. • Several distinct strategies to enhance the performance of Cs 2 AgBiBr 6 -based PSCs have been proposed. • The remaining key problems and future directions of Cs 2 AgBiBr 6 -based PSCs are discussed. [ABSTRACT FROM AUTHOR]

The ability to substitute oxygen evolution reaction (OER) in water splitting with ammonia oxidation reaction (AOR) represents an important endeavor in producing high-purity hydrogen with the lowered energy consumption. Due to the reduced overpotential of AOR over OER and preventing the hydrogen and oxygen mixing and thus possible explosion. Herein, we report the substitution of slow-kinetics OER with AOR to effectively boost hydrogen evolution reaction (HER) of wastewater electrolysis, thereby rendering energy saving as well as decontamination of ammonia (NH 3) in wastewater. Three-dimensional CoS@NiCu electrodeposited on Ni foam is employed as self-supporting bifunctional electrocatalysts for both AOR and HER. The XPS and in-situ Raman studies reveal the generation of electrocatalytically active cobalt oxyhydroxide (CoOOH) on CoS@NiCu during the course of AOR. Interestingly, the density functional theory (DFT) calculation unveils that NH 3 preferentially adsorbing on the surface of electrocatalyst prolongs the Co-S bond length, thus promoting the bond cleavage and accelerating the formation of active CoOOH species. Moreover, the rate-determining step of AOR according to the Gerischer-Mauerer (G-M) mechanism only has a 1.79 eV energy barrier to overcome. The electrochemical impedance spectroscopy investigation suggests that the AOR enables an enhanced interfacial charge transfer. As such, the hydrogen evolution rate of the AOR-HER system reaches 41.9 μmol h−1, representing 3.2-fold increase in hydrogen production over the conventional OER-HER water splitting. This study highlights a promising perspective of integrating AOR with HER to synergize efficient hydrogen production. [Display omitted] • NH 3 is readily adsorbed on the catalyst surface over H 2 O as a result of the low adsorption energy of NH 3 (-2.25 eV). • The adsorption of NH 3 on the catalyst surface expands the Co-S bond length, yielding catalytically active CoOOH. • The AOR-HER system outperforms the OER-HER counterpart, representing 3.2-fold increase in hydrogen production. • Nearly no O 2 generation, thus effectively circumventing the possible explosion hazard of the H 2 /O 2 mixing. [ABSTRACT FROM AUTHOR]

The removal of oil mist is essential for industrial process and worker's occupational health, as the oil mist will not only damage the industrial production device, but also increase human inhalation exposure risk. Traditional filters focus on high-efficiency low-resistance structured design for air filtration, while there is little research on cyclically sustainable filters for oil-mist filtration. Here, we developed a chitosan aerogel based on sustainable sandwich structure filter (NW-CS-Nylon 6) with thickness-direction asymmetric wettability and pore size differences, including polypropylene nonwoven fabric, chitosan aerogel and Nylon 6 nanofibrous membrane. Spray-coating was used to endow the Nylon 6 nanofibrous membrane with oleophobicity, and provide the whole filter with directional oil-transport function. Results revealed that the initial filtration efficiency and pressure drop of the oil-mist was 99.4%, 0.5 kPa, respectively. Remarkably, the ultra-high filtration efficiency of 99% and 98% was still maintained when the filtration was carried out for 50 and 100 times. Compared with traditional filters, it had higher filtration efficiency and lower pressure drop when continuously recycled, which had important research significance for filter recycling and energy saving in the future. [Display omitted] • A sandwich structured chitosan-aerogel nonwoven filter with asymmetric wettability and pore size differences was developed. • It has a high filter efficiency (99.4%) and low pressure drop (0.5 kPa). • After 100 filtration cycles, the filter still maintains a high filtration efficiency of 98%. [ABSTRACT FROM AUTHOR]

It is very attractive to find a cheap and efficient cocatalyst for enhancing the H 2 generation of graphitic carbon nitride (CN) under visible light. To achieve that, we proposed a novel two-step method to deposit sub-10 nm metallic Ni 2 P particles on the surface of CN sheets for a maximized interfacial contact. Characteristic results confirmed the establishment of ohmic heterojunction upon Ni 2 P-modification of CN, which deemed to be an effective measure to alleviate photo-charges recombination. In addition to facilitating spatial separation of charges, Ni 2 P could also enhance the optical properties of CN while reducing its impedance for interfacial electron shuttling. Better still, the P-end of Ni 2 P is highly electronegative, offering desirable H+-capturing capability for enhanced H 2 generation. These give rise to an improved H 2 production of Ni 2 P/CN composite, optimally at 645.3 μmol g−1·h−1 as compared to immeasurable H 2 yielded by the pristine CN. Such photocatalytic performance is even comparable to the Pt-modified CN photocatalyst (640.6 μmol g−1·h−1). In recyclability test, a notable activity suppression of 33.17% was recorded after four reaction cycles. This can be ascribed to the pronounced photo-corrosion of the Ni 2 P cocatalyst during photoreaction. Nonetheless, a remarkably high H 2 generation (1328.6 μmol g−1 in 3 h) was still attained at 4th cycle. This justifies the effectiveness of our synthesized Ni 2 P cocatalyst in enhancing H 2 generation of CN under visible light irradiation. • Sub-10 nm Ni 2 P was deposited on g-C 3 N 4 for enhanced H 2 generation. • Ohmic contact was successful formed at the interface Ni 2 P/g-C 3 N 4 photocatalyst. • 3 wt% Ni 2 P/g-C 3 N 4 prompts comparable H 2 generation to 3 wt% Pt/g-C 3 N 4. [ABSTRACT FROM AUTHOR]

• This is the first meta-analysis of the worldwide prevalence of Cryptosporidium parvum in dairy calves. • The degree of intensive rearing and age are important risk factors for C. parvum infection in dairy calves. • There are many subtypes of C. parvum in dairy calves in different regions. • The subtype families of C. parvum vary in different geographical regions. Cryptosporidium is a significant zoonotic pathogen that often occurs in dairy cattle. We conducted a systematic review and meta-analysis of the prevalence of Cryptosporidium parvum infection in dairy calves worldwide to help improve global animal husbandry and public policy implementation. Published articles were obtained from PubMed and Web of Science from January 1, 2000 to December 31, 2021. The prevalence of C. parvum infection in dairy calves was estimated using a random effects model, and the sources of heterogeneity were explored using meta-regression. In total, 118 datasets were included in the final quantitative analysis. The results showed that the global prevalence of C. parvum in dairy calves was 21.9% (7755/42,890; 95% confidence interval: 19.9–23.9%). C. parvum infection was high in pre-weaned dairy calves (24.9%, 6706/29,753) and diarrhea dairy calves (33.6%, 1637/6077). In countries with low dairy stocking density (<10 cows/farm), the prevalence of C. parvum in dairy calves was also relatively low (15.2%, 1960/16,584). Three subtype families [IIa (72.2%, 2293/3177), IId (27.4%, 872/3177), and IIl (0.4%, 12/3177)] were detected in dairy calves globally from selected studies. C. parvum IIa was the dominant zoonotic subtype. In the IIa subtype family of C. parvum , the proportions of subtypes from high to low (top nine) were IIaA15G2R1 (32.4%, 742/2293), IIaA18G3R1 (11.8%, 271/2293), IIaA13G2R1 (8.2%, 187/2293), IIaA16G1R1 (6.4%, 147/2293), IIaA20G1R1 (3.5%, 81/2293), IIaA16G3R1 (3.4%, 78/2293), IIaA17G2R1 (2.7%, 62/2293), IIaA18G1R1 (2.5%, 58/2293), and IIaA15G1R1 (2.4%, 56/2293). In the IId subtype family of C. parvum , the proportions of subtypes (top four) were IIdA19G1 (36.0%, 314/872), IIdA15G1 (27.3%, 238/872), IIdA20G1 (16.2%, 141/872), and IIdA14G1 (13.0%, 113/872). Furthermore, IId is commonly found in China (771/872). The study results indicated that the IIa subtype family is globally prevalent, while IId is found in Asia, Europe, and Africa and IIl is only found in Europe. Diarrhea in dairy calves is associated with C. parvum infection and a significantly higher prevalence is observed in diarrheic calves. Age and stock density are two significant risk factors in the prevalence of C. parvum in dairy calves. The prevention and control of this zoonosis in dairy calves should receive greater attention, especially in regions with a high degree of intensive dairy farming. [ABSTRACT FROM AUTHOR]

[Display omitted] Antifouling coatings play a crucial role in preventing the adhesion of marine organisms, bacteria, and blood, making them a primary strategy for combating biofouling in the marine industry. However, conventional antifouling coatings suffer from drawbacks such as high toxicity, limited abrasion resistance, and unstable polymer degradation rates, which can have adverse effects on the environment, economy, and human health. Thus, there is an urgent need for the development of sustainable and nontoxic antifouling coatings. This review first presents four major antifouling strategies: traditional coatings based on wettability, traditional coatings with protective structures, nontoxic coatings based on main chain degradable polymers, and nontoxic coatings combining main chain degradation with branch chain hydrolysis polymers. Second, the review provides a comprehensive overview of antifouling coatings with diverse functionalities, including antibacterial, anti-protein, anti-blood, anti-incrusting, adhesive, self-healing, and corrosion-resistant properties. Then, the application of antifouling coatings in marine environments and the medical field is thoroughly explored. Additionally, the review addresses the current challenges encountered by antifouling coatings. Finally, a forward-looking perspective is presented, envisioning future advancements in this field. By addressing these aspects, this review aims to stimulate further development and innovation in the realm of antifouling coatings. [ABSTRACT FROM AUTHOR]

The vanadium precipitation liquor produced by the vanadium slag extraction process contains various valuable elements, which are not utilized at high value. In this paper, chromium is recovered through aluminum salt impurity removal - chemical reduction precipitation method. Moreover, the ammonia nitrogen and sodium sulfur in the vanadium precipitation liquor are recovered by stripping and crystallization, thereby achieving comprehensive resource recovery and utilization. The aluminum salt slag removal reduction chemical precipitation method is used to separate Cr from Si, Ca and V impurities. As a result, the obtained Cr 2 O 3 product has a purity of 98.20%, the chromium recovery efficiency is 97.58%, and the silicon removal efficiency reaches 99.66%. The ammonia nitrogen was recovered by stripping, which would be reused to the vanadium precipitation process, with an ammonia nitrogen stripping efficiency of 98%. The purity of NH 4 Cl is 99.13% and meets the 99-level national standard. The Na 2 SO 4 was recovered by evaporation concentration - crystallization method, which would be reused to the vanadium slag roasting process, with a Na 2 SO 4 recovery efficiency of 88.38%. And the purity of Na 2 SO 4 is 98.85%, which meets the industrial standard for Class II Na 2 SO 4 products. The final solution after comprehensive recovery of valuable elements would be reused to the leaching process, thereby achieving water circulation. This process realizes the high-value utilization of chromium, ammonia, nitrogen, sodium and sulfur, and has no wastewater discharge and is an environment-friendly route. [Display omitted] • Si impurity effect on Cr recovery from vanadium precipitation liquor (VPL) is analyzed. • Valuable elements recovery and water circulation method for VPL is proposed. • Optimum recovery parameters on Cr 2 O 3 , NH 4 Cl and Na 2 SO 4 high-value products are studied. [ABSTRACT FROM AUTHOR]

With the miniaturization and integration of electronic devices heat conduction becomes a serious problem. Graphene films catch research's attention because of its excellent thermal performance and graphene oxide (GO) has been used as the most common precursor to prepare graphene films. But mostly film fabricated from GO is thinner than 30 μm and much thicker films are required to meet certain requirements. Also taking GO as raw material has many disadvantages such as the introduction of massive concentrated sulfuric acid and metal ions, huge weight loss in heat treatment and so on. Herein, we propose a new strategy to prepare graphene nanosheet films (GNFs) with a thickness of 100 μm by vacuum filtration of expand graphite through weak oxidation (WEG). Unlike common strategy, WEG without any metal ions introduced instead of GO is chosen as our raw material. The addition of nonionic surfactant and the employment of microfluidization can stabilize WEG dispersion. After graphitization at 2800 °C WEGF is transferred to GNF. The obtained 100 μm-thick film possesses a decent in-plane thermal conductivity (TC) of 760 W/mk and electrical conductivity (EC) of 5.2×105 S/m. Thick films with high TC can guarantee passing more heat flux and fill in larger gaps inside devices. [ABSTRACT FROM AUTHOR]

High-temperature particulate matter (PM), commonly produced by daily power generation, industrial smokestacks, and vehicle exhaust emissions, causes a significant risk to public health and environmental sustainability. The current strategy for solving these problems is to utilize adsorption filtration technology. In this work, we successfully constructed a bioinspired honeycomb structured aerogel with nano/micron fiber-reinforced polyimide gradient by using two strategies of fiber-reinforced filler and stepwise directional freezing technique. It overcomes the high shrinkage of polyimide aerogel and exhibits super elastic recovery performance without damage after 100 compression cycles at 50% strain, as well as high flame-retardancy and low thermal conductivity (32.14 mW m−1 K−1). Meanwhile, it shows excellent air filtration efficiency of about 97% and pressure drop of about 90 Pa after 50 cycles, as well as an excellent oil/organic solvent absorption performance and recoverability. In principle, the gradient structure with gradual change shows the "medium pore-small pore" cascade interception effect in the direction of airflow velocity propagation, which successfully achieves the selective and precise interception of polydisperse particles and the stratified accumulation of particles. It further significantly extends the filter service life and provides new insights into the upgrade of new high-temperature filters with significant research implications. [Display omitted] • A gradient polyimide aerogel is constructed by using fiber-reinforced filler and stepwise directional freezing technique. • The fiber-reinforced aerogel shows high mechanical stability and super elastic recovery performance. • It exhibits high flame retardancy and low thermal conductivity (32.14 mW (m K)−1). • The gradient aerogel shows an excellent air filtration efficiency of 97% and pressure drop of about 90 Pa after 50 cycles. • The large-scale preparation of aerogel is feasible due to simple methods and low-cost materials. [ABSTRACT FROM AUTHOR]

Polyphenylene sulfide (PPS), commonly used as a core material for high-temperature flue gas treatment, exhibits elevated viscosity when processed even at temperature exceeding 280 °C. In this study, a novel high-flowability PPS-based composite was fabricated through the incorporation of graphitic carbon nitride (g-C 3 N 4) via a well-established melt extrusion procedure. The enhancement of flowability in PPS was verified, and the material's texture structures and fundamental properties of composites with varying contents were determined. The composites exhibit well-dispersed g-C 3 N 4 , a significant reduction in shear viscosity (>10 %), a notable increase in melt index (>30 %), improved crystallinity, and comparable or superior performance compared to pure PPS. When the g-C 3 N 4 was introduced into the PPS matrix, a phase-separated composite structure was formed. This structure reduces the entanglement degree between the PPS molecular chains and provides more space for free-movement of the PPS chains, and thus the improvement in flowability for the composites can be clearly demonstrated. Therefore, g-C 3 N 4 can be used as a novel flow modifier to enhance the flowability and stability of PPS resin without compromising its fundamental properties, which offers significant prospects for improving productivity, optimizing energy usage, and managing costs for PPS-based products. [Display omitted] • PPS/g-C 3 N 4 composites was fabricated via a mature melt blending procedure. • g-C 3 N 4 could improve the flowability of PPS under high temperature processing. • π-π interaction improved the compatibility between PPS and g-C 3 N 4. • The composites achieved comparable or better properties under normal measurement. [ABSTRACT FROM AUTHOR]