Developing bifunctional efficient electrocatalysts for both the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) is in high demand for the development of overall water‐splitting ...devices. In particular, the electrocatalytic performance can be largely improved by designing positive nanoscale‐heterojunction with well‐tuned interfaces. Herein, a novel top‐down strategy is reported to construct the oxide/sulfide heterostructures (N‐NiMoO4/NiS2 nanowires/nanosheets) as a multisite HER/OER catalyst. Starting with the NiMoO4 nanowires, nitridation in a controlled manner enables activation of Ni sites in NiMoO4 and then yields oxide/sulfide heterojunction by directly vulcanizing the highly composition‐segregated N‐NiMoO4 nanowires. The abundant epitaxial heterogeneous interfaces at atomic‐level facilitate the electron transfer from N‐NiMoO4 to NiS2, which further cooperate synergistically toward both the hydrogen and oxygen generation in alkali solution. Furthermore, with N‐NiMoO4/NiS2 grown carbon fiber cloth as the engineering electrode, the assembled N‐NiMoO4/NiS2–N‐NiMoO4/NiS2 system can deliver a current density of 10 mA cm−2 with the cell voltage of 1.60 V in the water‐splitting reaction. This current density is 3.39 times higher than that of the Pt–Ir set (2.95 mA cm−2). The excellent catalytic performance offered of N‐NiMoO4/NiS2 nanowires/nanosheets presents a great example to demonstrate the significance of interface engineering in the field of electrocatalysis.
A novel top‐down strategy is performed to construct oxide/sulfide heterostructures (N‐NiMoO4/NiS2 nanowires/nanosheets). The abundant epitaxial heterogeneous interfaces faciliate electron transfer from N‐NiMoO4 to NiS2, promoting their electrocatalytic ability. Moreover, with N‐NiMoO4/NiS2 working as the cathode/anode electrodes, the water‐alkali electrolyzer only requires a cell voltage of 1.60 V to achieve 10 mA cm−2.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
The development of active and durable bifunctional electrocatalysts for overall water splitting is mandatory for renewable energy conversion. This study reports a general method for controllable ...synthesis of a class of IrM (M = Co, Ni, CoNi) multimetallic porous hollow nanocrystals (PHNCs), through etching Ir‐based, multimetallic, solid nanocrystals using Fe3+ ions, as catalysts for boosting overall water splitting. The Ir‐based multimetallic PHNCs show transition‐metal‐dependent bifunctional electrocatalytic activities for both the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in acidic electrolyte, with IrCo and IrCoNi PHNCs being the best for HER and OER, respectively. First‐principles calculations reveal a ligand effect, induced by alloying Ir with 3d transition metals, can weaken the adsorption energy of oxygen intermediates, which is the key to realizing much‐enhanced OER activity. The IrCoNi PHNCs are highly efficient in overall‐water‐splitting catalysis by showing a low cell voltage of only 1.56 V at a current density of 2 mA cm−2, and only 8 mV of polarization‐curve shift after a 1000‐cycle durability test in 0.5 m H2SO4 solution. This work highlights a potentially powerful strategy toward the general synthesis of novel, multimetallic, PHNCs as highly active and durable bifunctional electrocatalysts for high‐performance electrochemical overall‐water‐splitting devices.
A class of Ir‐based, multimetallic, porous hollow nanocrystals is synthesized using a general method through the use of Fe3+ ions to etch Ir‐based solid nanocrystals, as highly efficient, bifunctional catalysts for boosting overall‐water‐splitting catalysis.
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Abstract
Background
The high cost and insufficient supply of human papillomavirus (HPV) vaccines have slowed the pace of controlling cervical cancer. A phase III clinical trial was conducted to ...evaluate the efficacy, safety, and immunogenicity of a novel Escherichia coli-produced bivalent HPV-16/18 vaccine.
Methods
A multicenter, randomized, double-blind trial started on November 22, 2012 in China. In total, 7372 eligible women aged 18–45 years were age-stratified and randomly assigned to receive three doses of the test or control (hepatitis E) vaccine at months 0, 1, and 6. Co-primary endpoints included high-grade genital lesions and persistent infection (over 6 months) associated with HPV-16/18. The primary analysis was performed on a per-protocol susceptible population of individuals who were negative for relevant HPV type-specific neutralizing antibodies (at day 0) and DNA (at day 0 through month 7) and who received three doses of the vaccine. This report presents data from a prespecified interim analysis used for regulatory submission.
Results
In the per-protocol cohort, the efficacies against high-grade genital lesions and persistent infection were 100.0% (95% confidence interval = 55.6% to 100.0%, 0 of 3306 in the vaccine group vs 10 of 3296 in the control group) and 97.8% (95% confidence interval = 87.1% to 99.9%, 1 of 3240 vs 45 of 3246), respectively. The side effects were mild. No vaccine-related serious adverse events were noted. Robust antibody responses for both types were induced and persisted for at least 42 months.
Conclusions
The E coli-produced HPV-16/18 vaccine is well tolerated and highly efficacious against HPV-16/18–associated high-grade genital lesions and persistent infection in women.
This paper evaluated the excretion masses and environmental occurrence of 11 classes of 50 antibiotics in six typical swine and dairy cattle farms in southern China. Animal feeds, wastewater and ...solid manure samples as well as environmental samples (soil, stream and well water) were collected in December 2010 from these farms. Twenty eight antibiotics, including tetracyclines, bacitracin, lincomycin, sulfonamides, fluoroquinolones, ceftiofur, trimethoprim, macrolides, and florfenicol, were detected in the feeds, animal wastes and receiving environments. The normalized daily excretion masses per swine and cattle were estimated to be 18.2mg/day/swine and 4.24mg/day/cattle. Chlortetracycline (11.6mg/day/swine), bacitracin (3.81mg/day/swine), lincomycin (1.19mg/day/swine) and tetracycline (1.04mg/day/swine) were the main contributors to the normalized daily excretion masses of antibiotics per swine, while chlortetracycline (3.66mg/day/cattle) contributed 86% of the normalized daily excretion masses of antibiotics per cattle. Based on the survey of feeds and animal wastes from the swine farms and interview with the farmers, antibiotics excreted by swine were mainly originated from the feeds, while antibiotics excreted by dairy cattle were mainly from the injection route. If we assume that the swine and cattle in China excrete the same masses of antibiotics as the selected livestock farms, the total excretion mass by swine and cattle per annum in China could reach 3,080,000kg/year and 164,000kg/year. Various antibiotics such as sulfonamides, tetracyclines, fluroquinolones, macrolides, trimethoprim, lincomycin and florfenicol were detected in well water, stream and field soil, suggesting that livestock farms could be an important pollution source of various antibiotics to the receiving environments.
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► Twenty six antibiotics were quantified in six swine and dairy farms. ► The normalized excretion mass of antibiotics per swine was more than per cattle. ► Growth promoters contributed above 80% of the excretion mass in swine farms. ► Total excretion mass by swine and cattle in China could reach 3080 and 164t/a. ► Significant concentrations of antibiotics were found in the receiving environment.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Electrocatalysts with a high efficiency and durability for the hydrogen evolution reaction (HER) hold tremendous promise for next‐generation energy conversion. Among the state‐of‐art catalysts for ...HER, organic–inorganic hybrid nanosheets exhibit a great potential with the merits of high activity, good durability, and low cost. Nevertheless, there is no general method for the synthesis of binary metal phosphide hybrid nanosheet HER catalysts with a tunable morphology and composition. Herein, we report a facile approach for the synthesis of nanosheets consisting of a binary cobalt nickel phosphide hybrid with a hierarchically porous nanostructures using an oxidation– phosphorization process. The as‐optimized hybrid nanosheets annealed at 350 °C yield the highest pH‐universal activity with overpotentials of 148, 111, and 173 mV in acidic, alkaline, and neutral media, respectively. Besides the promoted mass diffusion in the hierarchically porous structure, the extraordinary performance can be also attributed to the weakened adsorption of hydrogen as a result of the tunable composition of Co and Ni, which was revealed by first‐principles calculations.
It's not about the pH: Electrocatalysts with a high efficiency and durability for the hydrogen evolution reaction (HER) hold tremendous promise for next‐generation energy conversion. Herein, we report a facile approach for the synthesis of organic–inorganic hybrid binary metal phosphide nanosheet catalysts for the HER with a tunable morphology and composition. The as‐optimized CoxNiyP exhibits a high pH‐universal activity in a wide pH range.
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Semi-hydrogenation of acetylene is of great importance for both industry and academia. High prices and limited supplements of noble metals leave room for developing base metal catalysts. Experiments ...revealed the atomically dispersed Cu supported by Al2O3 with excellent long-term stability and high ethylene selectivity, but the physical nature has rarely been investigated theoretically. DFT calculations and microkinetic modeling revealed that the surface OH species could stabilize Cu1/Al2−δO3 and enhance its catalytic performance. The selectivity of ethylene formation decreases with increasing copper clusters (e.g., Cu1/Al2−δO3> Cu4/Al2−δO3> Cu8/Al2−δO3), meaning that the atomically dispersed copper may be a potential candidate for acetylene semi-hydrogenation. The structures of a series of single site catalysts M1/Al2−δO3 (M = Fe, Co, Ni, Ag, Au) are similar to that of Cu1/Al2−δO3, but their performances in catalyzing acetylene semi-hydrogenation are different. M1/Al2−δO3 (M = Ag, Au) shows higher selectivity than Cu1/Al2−δO3, while M1/Al2−δO3 (M = Fe, Co, Ni) demonstrates a higher turnover frequency (TOF) of ethylene than Cu1/Al2−δO3. Moreover, our results indicate that the Ni1–Cu1/Al2−δO3 alloy shows both high activity and ethylene selectivity. The present results show a compensation between the reactivity and the selectivity, suggesting that alloys of VIIIB metals with IB metals like Ni1–Cu1/Al2−δO3 may be efficient candidate catalysts in acetylene selective hydrogenation.
•Low or high doses of VLP HPV vaccine were well tolerated in 9–45 year-old females.•Three HPV vaccinations elicited protective immune responses in 100% of vaccinees.•HPV vaccination did not result in ...any severe or serious adverse event.•Reactogenicity and immunogenicity were not affected by increasing dosage of HPV vaccine.
We evaluated the safety and immunogenicity of high and low doses of a novel pichia pastoris-expressed bivalent (types 16 and 18) human papillomavirus (HPV) virus-like particle vaccine.
In this randomized, double-blind, placebo-controlled phase 1 trial, we enrolled 160 healthy females aged 9–45 years in Guangxi, China who were randomized (1:1:2) to receive either low (0.5 mL) or high (1.0 mL) dosages of bivalent HPV vaccine, or placebo (aluminum adjuvant) in a 0, 2, 6 months schedule. Adverse events and other significant conditions that occurred within 30 days after each vaccination were recorded throughout the trial. Sera were collected at days 0, 60, 180 and 210 to measure anti-HPV 16/18 neutralizing antibodies.
A total of 160 participants received at least one dose of the HPV vaccine and 152 completed the three dose vaccination series. Reporting rates of adverse events in placebo, low dose (0.5 mL) and high dose (1.0 mL) groups were 47.5 %, 55.0 % and 55.0 %, respectively. No serious adverse events occurred during this trial. 100 % of the participants who received three doses of the HPV vaccine produced neutralizing antibodies against HPV 16/18 vaccine. For HPV 16 and HPV 18, the geometric mean titers (GMTs) were similar between the low dose group (GMTHPV 16 = 10816 95 % CI: 7824–14953), GMTHPV 18 = 3966 95 % CI: 2693–5841) and high dose group (GMT HPV 16 = 14482 95 % CI: 10848–19333, GMT HPV 18 = 3428 95 % CI: 2533–4639).
The pichia pastoris-expressed bivalent HPV vaccine was safe and immunogenic in Chinese females aged 9–45 years. The low dosage (0.5 mL) was selected for further immunogenicity and efficacy study.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Transition-metal nitrides (TMNs), especially iron-based TMNs, have high electrical conductivity, superior chemical stability and unique oxygen-reaction ability, and have emerged as a new form of ...noble metal-free electrocatalysts. In this paper, we demonstrate that the ORR-active/OER-inert single function catalyst Fe-N can be made as the OER/ORR-active bifunctional catalyst Co-Fe-N by controlled substitution of Fe with Co. To obtain atomic insights of the Co-enhanced OER catalysis, we develop a new exfoliation method to prepare atomically thin (1.1 nm) nanosheets (NSs) of CoxFe1-xN0.5 (x = 0, 0.05, 0.1, 0.15 and 0.2). Our studies show that both electronic structure and local binding environment of Fe are modified by Co substitution and the Co-Fe-N NSs show a volcano−like OER catalysis with Co0.15Fe0.85N0.5 NSs being the most efficient OER catalyst, showing the lowest overpotential of 266 mV at 10 mA cm−2, a Tafel slope of ∼30 mV dec−1, and excellent stability in the 1.0 M KOH OER condition. Density functional theory (DFT) calculations suggest that the Co-Fe sites in the Co0.15Fe0.85N0.5 structure are optimized to promote OH* to O* conversion, O*-O* coupling and O2 formation. The Co0.15Fe0.85N0.5 NSs are a class of new noble-metal-free catalyst for OER.
Atomically thin (1.1 nm) Co-Fe-N nanosheets are fabricated for the maximum Co exposure to the reaction environment. ORR-active/OER-inert single function catalyst Fe-N can be made as the OER/ORR-active bifunctional catalyst Co-Fe-N by controlled substitution of Fe with Co, with Co0.15Fe0.85N0.5 NSs being the best content. The introduced Co can both modify the electronic structure of Fe, and assist Fe as double−metal sites for OER process. Display omitted
•Atomically thin CoxFe1-xN0.5 nanosheets were synthesized to warrant the maximum atom exposure to the reaction environment.•Single-functional catalyst Fe-N can be made as bifunctional catalyst Co-Fe-N by doping Co with the content of 15%.•The Co-Fe sites Co-Fe-N network structure do show a synergistic effect on the OER catalysis enhancement.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
We assessed the safety, immunogenicity and antibody persistence of two- and three-dose schedules of the novel bivalent HPV16/18 vaccine (HPV-2, Walrinvax) in the per-protocol target population of ...initially seronegative 9–14 year-old girls, including a non-inferiority comparison with the three-dose schedule in 18–26 year-old women.
This randomized phase 3b trial in Guangxi Zhuang Autonomous Region, China, involved healthy Chinese females in two age cohorts; 600 girls aged 9–14 years and 300 women aged 18–26 years. Girls were randomly assigned (1:1) to receive either two (Months 0,6) or three (Months 0,2,6) intramuscular doses of HPV-2. All participants were monitored for immunogenicity as neutralizing antibodies up to 36 months. Primary objectives were non-inferiority analyses of immunogenicity between two- and three-dose girl groups and adult women at Month 7; safety assessments were based on participant-completed diary cards.
All groups demonstrated marked increases in neutralizing antibodies against HPV 16 and 18 that persisted above baseline to 36 months. Month 7 responses in both girl groups were non-inferior to those in the women and were statistically higher after two-doses than girls or women who received three doses. GMTs waned after month 7, but then maintained a plateau level until month 36. Vaccination was well tolerated in all groups with no serious adverse events reported.
Immune responses to two doses of HPV-2 vaccine in adolescent girls were non-inferior to those after three doses in young women, an age cohort in which clinical efficacy of HPV-2 against cervical cancer has been demonstrated.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
As a synthetic androgen, 17α‐methyltestosterone (MT) is widely used in aquaculture to induce sex reversal and may pose a potential risk to aquatic organisms. This ecological risk has attracted the ...attention of many scholars, but it is not comprehensive enough. Thus, the adverse effects of MT on zebrafish (Danio rerio) were comprehensively evaluated from gonadal histology, as well as the mRNA expression levels of 47 genes related to hypothalamic‐pituitary‐gonadal (HPG) axis, germ cell differentiation, sex determination, and hypothalamus‐pituitary‐thyroid (HPT) axis. Adult zebrafish with a female/male ratio of 5:7 were exposed to a solvent control (0.001% dimethyl sulfoxide) and three measured concentrations of MT (5, 51 and 583 ng/L) for 50 days. The results showed that MT had no significant histological effects on the ovaries of females, but the frequency of late‐mature oocytes (LMO) showed a downward trend, indicating that MT could induce ovarian suppression to a certain extent. The transcriptional expression of activating transcription factor 4b1 (atf4b1), activating transcription factor 4b2 (atf4b2), calcium/calmodulin‐dependent protein kinase II delta 1 (camk2d1), calcium/calmodulin‐dependent protein kinase II delta 2 (camk2d2) and calcium/calmodulin‐dependent protein kinase II inhibitor 2 (camk2n2) genes in the brain of females increased significantly at all treatment groups of MT, and the mRNA expression of forkhead box L2a (foxl2) and ovarian cytochrome P450 aromatase (cyp19a1a) genes in the ovaries were down‐regulated by 5 and 583 ng/L group, which would translate into inhibition of oocyte development. As compared to females, MT had relatively little effects on the reproductive system of males, and only the transcriptional alterations of synaptonemal complex protein 3 (sycp3) and 17‐alpha‐hydroxylase/17,20‐lyase (cyp17) genes were observed in the testes, not enough to affect testicular histology. In addition, MT at all treatments strongly increased corticotropin‐releasing hormone (crh) transcript in the brain of females, as well as deiodinase 2 (dio2) transcript in the brain of males. The paired box protein 8 (pax8) gene was significantly decreased at 51 or 583 ng/L of MT in both female and male brains. The above results suggest that MT can pose potential adverse effects on the reproductive and thyroid endocrine system of fish.
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