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Completely removing chromium (Cr) from contaminated water with simultaneous reduction of Cr(VI) and sequestration of Cr(III) is an efficient strategy to restrain its migration in natural water. Herein, sulfonated carbon hemisphere (Labeled as CHS, Inner diameter: 150 nm) worked as a supporter to hold mesoporous TiO 2 (MT) nanoparticles (Diameter: 10 nm), constructing a bifunctional catalyst with photocatalytic activity and adsorption capacity. During a typical Cr removal process, efficient photocatalytic reduction Cr(VI) performed alongside the utter adsorption of the generated Cr(III) on the sulfonated CS by ion exchange for the grafted -SO 3 H+. The reaction rate constant (k) for removing Cr(VI) by TiO 2 -C-SO 3 H is 0.04998 min−1, which is 3.72 times higher than that (0.01342 min−1) unmodified TiO 2 -C, and 23.68 times and that of MT (0.00223 min−1). No residual Cr was determined in the treated water. The highest removal efficiency was achieved when the mass ratio of carbon and TiO 2 hemispheres is 0.62%. Two factors contributing to the exceptional reduction efficiency include improved electron-hole separation efficiency endowed by the CHS conductive framework, sensitive light absorption. Ultimately, the -SO 3 H+ grafted on CHS can immobilize Cr(III) by ion exchange, performing like a resin, which realizes the total removal of Cr(VI) or Cr(III) and restrains the possible hazardous influence. [Display omitted] • An all-in-one bifunctional TiO 2 -C-SO 3 H was prepared. • The strong contact between TiO 2 and CHS constructs an electron channel. • Numerous de-protonation of grafted -SO 3 H+ to anchor Cr3+ cations. • Sulfonated C-TiO 2 has the prospects of actual contaminated water treatment. • TiO 2 -C-SO 3 H photocatalyst has long-term durability. [ABSTRACT FROM AUTHOR]

Oxygen vacancy/Ti3+ engineered TiO 2 nanotube arrays were prepared through electrochemical strategy at high potential (−6 V). The electrons surging from DC power initiate the valance decline of Ti4+, and countless H 2 bubbles released from TiO 2 surface lead to the in-situ exfoliation of some TiO 2 tiny debris, generating point defects containing Ti3+ inside the TiO 2 and oxygen vacancy (OV) embedded on TiO 2. The generated Ti3+/ OV help TiO 2 to increase the harvest toward visible light and serve as active sites for activating molecular oxygen to form superoxide radical (·O 2 -). Besides, as improved separation of electron-hole pairs endowed by the defects, the yield of hydroxyl radicals (·OH) is enhanced compared with the pristine TiO 2. Chloramphenicol (CAP, an antibiotic) molecules can be efficiently degraded with the reduced TiO 2 under the visible light with its degradation and evolution pathway expounded in detail. Fukui index is employed to anticipate the probable sites that are subjected to oxidation by·OH and the MS spectra evidence that the·OH governs the decomposition routes of CAP molecules. ECOSAR simulation evaluates the toxicity of CAP and the intermediates, demonstrating that the final products from the photocatalysis do not post any hazardous risk on ecosystem. [Display omitted] • Oxygen vacancy/Ti3+ engineered TiO 2 nanotube arrays were constructed by in-situ exfoliation. • Oxygen vacancy and Ti3+ serve as intrinsic active sites. • Hydroxyl radicals govern the degradation pathway of CAP molecule. • Final products from the photocatalysis do not pose any hazardous risk on ecosystem. [ABSTRACT FROM AUTHOR]

Photoelectrocatalysis (PEC) is an effective approach to eliminate carcinogen hexavalent chromium (Cr(VI)) in wastewater, in which high-performance catalysts are crucial. Herein, controlled growth of thin molybdenum disulphide (MoS 2) nanosheets on self-supported tungsten trioxide (WO 3) created an all-solid-state MoS 2 /WO 3 heterojunction serving as electrode and catalyst simultaneously for removing Cr(VI). Countless small and thin MoS 2 nanoflakes build in a huge and porous interface for harvesting lights and adsorbing chromium species. And the highly conductive WO 3 substrate facilitates the transfer of those photoexcited-electron and therefore suppresses the recombination between electrons and holes. Furthermore, assisted by bias potential, electron streams from external circuit render an electron-rich interface at the MoS 2 /WO 3 cathode, accelerating the Cr(VI) reduction by PEC. At −1.2 V, the PEC reduction efficiency of Cr(VI) reaches 100% within 30 min, surpassing the pristine WO 3 by 2.7 times. The generated Cr(III) ions can be immobilized on the porous MoS 2 /WO 3 cathode through electrostatic attraction, enabling removal of total chromium. More importantly, the Cr(III) anchored to the catalyst can be effortlessly recovered by eluting with clean water, which also refreshes the MoS 2 /WO 3 cathode. This study provides a new approach to fabricating photoelectrodes for sustainable PEC reduction and treatment of Cr(VI) containing wastewater. [ABSTRACT FROM AUTHOR]

The rabies rapid fluorescent focus inhibition test (RFFIT) is the most widely used cell-based assay for detecting and quantitating rabies virus neutralizing antibodies (RVNA) in human serum. However, it is a complex, labor intensive, and somewhat subjective manual assay, the performance of which may be affected by a number of factors including the quality of cells and virus, variability of assay reagents and the skill and expertise of analysts. This study sought to identify and evaluate conditions that may impact RFFIT performance and RVNA detection by evaluating assay parameters including: different serial dilution scheme of serum samples in a 96-well microplate using semi-automated pipetting systems, the range of dose of challenge virus standard (CVS-11) strain of rabies virus, the effect of complement (C′), the effect of cell seeding density and passage number, the effect of diethylaminoethyl (DEAE) dextran concentration on virus infectivity, and the assay incubation period prior to immunostaining. In addition the evaluation of counting fluorescent foci using a microscope versus using scanned images from a cell imaging reader was performed in an effort to ease the reading of slides and have permanent records of the raw data. The results from optimization of each parameter are presented along with subsequent assay validation in accordance with the International Conference on Harmonization (ICH) guidelines. The improved and optimized RFFIT accuracy, linearity and sensitivity was demonstrated by testing World Health Organization (WHO)-1 and WHO-2 Standard Rabies Immune Globulins (SRIGs) and complete assay development and validation was performed in compliance with Good Clinical Laboratory Practice (GCLP) guidelines. [ABSTRACT FROM AUTHOR]

Seasonal influenza vaccines represent a positive intervention to limit the spread of the virus and protect public health. Yet continual influenza evolution and its ability to evade immunity pose a constant threat. For these reasons, vaccines with improved potency and breadth of protection remain an important need. We previously developed a next-generation influenza vaccine that displays the trimeric influenza hemagglutinin (HA) on a ferritin nanoparticle (NP) to optimize its presentation. Similar to other vaccines, HA-nanoparticle vaccine efficacy is increased by the inclusion of adjuvants during immunization. To identify the optimal adjuvants to enhance influenza immunity, we systematically analyzed TLR agonists for their ability to elicit immune responses. HA-NPs were compatible with nearly all adjuvants tested, including TLR2, TLR4, TLR7/8, and TLR9 agonists, squalene oil-in-water mixtures, and STING agonists. In addition, we chemically conjugated TLR7/8 and TLR9 ligands directly to the HA-ferritin nanoparticle. These TLR agonist-conjugated nanoparticles induced stronger antibody responses than nanoparticles alone, which allowed the use of a 5000-fold-lower dose of adjuvant than traditional admixtures. One candidate, the oil-in-water adjuvant AF03, was also tested in non-human primates and showed strong induction of neutralizing responses against both matched and heterologous H1N1 viruses. These data suggest that AF03, along with certain TLR agonists, enhance strong neutralizing antibody responses following influenza vaccination and may improve the breadth, potency, and ultimately vaccine protection in humans. [ABSTRACT FROM AUTHOR]

We assessed a dengue IgG rapid diagnostic test (RDT) and IgG enzyme-linked immunosorbent assay (ELISA) to determine their suitability for dengue prevaccination screening. Each exhibited ≥99% specificity. The RDT demonstrated no Zika cross-reactivity, while the ELISA displayed greater sensitivity. Both could safely guide vaccination in Puerto Rico pending availability of improved serotests. • Dengvaxia use requires identification of those with prior dengue infection (PDI). • An IgG ELISA and RDT used in Puerto Rico were evaluated for identifying PDI. • Both serotests exhibited ≥99% specificity, and the RDT had less flavivirus cross-reactivity. • Sensitivity was higher for the ELISA compared to the RDT. • Both tests could be used for pre-vaccination screening until a more sensitive serotest is approved. [ABSTRACT FROM AUTHOR]