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The swine industry annually suffers significant economic losses caused by porcine reproductive and respiratory syndrome virus (PRRSV). Because the available commercial vaccines have limited protective efficacy against epidemic PRRSV, there is an urgent need for innovative solutions. Nanoparticle vaccines induce robust immune responses and have become a promising direction in vaccine development. In this study, we designed and produced a self-assembling nanoparticle vaccine derived from thermophilic archaeal ferritin to combat epidemic PRRSV. First, multiple T cell epitopes targeting viral structural proteins were identified by IFN-γ screening after PRRSV infection. Three different self-assembled nanoparticles with epitopes targeting viral GP3, GP4, and GP5 proteins were constructed and mixed to generate a FeCocktail vaccine. Experiments showed that the FeCocktail vaccine effectively activated CD4 + and CD8 + T cells and effector memory T cells in mice. Piglets immunized with the FeCocktail vaccine generated specific antibodies and exhibited increased levels of PRRSV-specific IFN-γ produced by functional CD4 + and CD8 + cells. The FeCocktail also provided protective efficacy against PRRSV challenge, including mitigation of clinical symptoms, reduction of viral loads in serum and lungs, and the alleviation of lung tissue damage. In conclusion, this study offers a promising candidate vaccine for combating epidemic PRRSV, and affirms the utility of nanoparticle protein as a platform for next-generation PRRSV vaccine development.

Three new D-π-A-structured organic dyes, coded as SGT-138 , SGT-150 , and SGT-151 , with the expansion of π-conjugation in the π-bridge and acceptor parts have been developed to adjust HOMO/LUMO levels and to expand the light absorption range of organic dyes. Referring to the SGT-137 dye, the π-bridge group was extended from the 4-hexyl-4 H -thieno[3,2- b ]indole ( TI ) to the 9-hexyl-9 H -thieno[2',3':4,5]thieno[3,2- b ]indole ( TII ), and the acceptor group was extended from ( E )-3-(4-(benzo[ c ][1,2,5]thiadiazol-4-yl)phenyl)-2-cyanoacrylic acid ( BTCA ) to ( E )-3-(4-(benzo[ c ][1,2,5]thiadiazol-4-ylethynyl)phenyl)-2-cyanoacrylic acid ( BTECA ), where TII was introduced as a π-bridging unit for the first time. It was determined that both extensions are promising strategies to enhance the light-harvesting ability. They present several features, such as (i) efficiently intensifying the extinction coefficient and expanding the absorption bands; (ii) exhibiting enhanced intramolecular charge transfer in comparison with the SGT-137 ; and (iii) being favorable to photoelectric current generation of dye-sensitized solar cells (DSSCs) with cobalt electrolytes. In particular, the π-spacer extension from TI to TII was useful for modulating the HOMO energy levels, while the acceptor extension from BTCA to BTECA was useful for modulating the LUMO energy levels. These phenomena could be explained with the aid of density functional theory calculations. Finally, the DSSCs based on new SGT -dyes with an HC-A1 co-adsorbent presented good power conversion efficiencies as high as 11.23, 11.30, 11.05, and 10.80% for SGT-137 , SGT-138 , SGT-150, and SGT-151 , respectively. Furthermore, it was determined that the use of the bulky co-adsorbent, HC-A1, can effectively suppress the structural relaxation of dyes in the excited state, thereby enhancing the charge injection rate of SGT -dyes. The observations in time-resolved photoluminescence were indeed consistent with the variation in the PCE, quantitatively.

Efficient and stable electromagnetic-wave (EMW) absorption materials have attracted great attention in the field of reducing microwave pollution. Herein, FeCoNiCuTi x high-entropy alloys (HEAs) as electromagnetic-wave absorbing materials were prepared by a high-energy ball-milling method. The as-milled HEA powders presented a flaky shape with a high aspect ratio. Impedance matching was efficiently optimized by severe lattice distortion, which was caused by Ti incorporation. The introduced plentiful defects in FeCoNiCuTi x HEAs provided abundant polarization sites for dielectric loss. By tuning Ti contents, FeCoNiCuTi 0.2 HEAs delivered excellent EMW absorption performances. The maximal reflection loss (RL max ) values reached -47.8 dB at 10.86 GHz as thin as 2.16 mm, and the widest bandwidth was 4.76 GHz (5.97-10.73 GHz). Furthermore, the introduction of Ti enhanced corrosion resistance via increasing the charge transfer resistance of a passivated film. Those characteristics of FeCoNiCuTi x HEAs made these materials a practical gigahertz-range EMW absorber. Additionally, our findings provided a facile and tunable strategy for designing EMW absorbing materials, which was aimed at lightweight, highly efficient absorption, and resistance to harsh environments.

Zn(II)-porphyrin dyes ( SGT-030 and SGT-031 ) with extended auxiliary π-spacers in the donor (D) part have been prepared and applied to dye-sensitized solar cells (DSSCs). The porphyrin dyes contained the same D-ethynyl-zinc porphyrinyl ( ZnP )-ethynyl-benzothiadiazole-acceptor platform, but their donor groups varied from phenylene ( Ph ) in SGT-053 as a reference dye to the thieno[3,2- b ]benzothiophene ( TBT ) and 4-hexyl-4 H -thieno[3,2- b ]indole ( TI ) moieties in SGT-030 and SGT-031 , respectively. The effects of the extended auxiliary π-spacer in the D-π-A-structured porphyrin sensitizers on the molecular and photovoltaic properties were investigated via photophysical and electrochemical experiments as well as theoretical calculations. With the trend in conjugation length ( Ph < TBT ≈ TI ) and the donating ability of the π-spacer ( Ph < TBT < TI ), the absorption maxima and molecular absorptivity increased in the order SGT-053 ( Ph ) < SGT-030 ( TBT ) < SGT-031 ( TI ). The incorporation of TBT and TI promoted significant enhancements in the light-harvesting properties by reducing the energy gap and efficiently improving electronic communication. The DSSCs based on SGT-030 (10.80%) and SGT-031 (10.89%) with coadsorption of 4-(3,6-bis(4-((2-ethylhexyl)oxy)phenyl)-9 H -carbazol-9-yl)benzoic acid in conjunction with the [Co(bpy) 3 ] 2+/3+ -based electrolyte showed better power conversion efficiency than that of SGT-053 (9.10%). Electrochemical impedance spectroscopy analysis unveiled that the difference in J sc and V oc originates mainly from the twisted orientation between D and ZnP by the introduction of TBT and TI . This result indicated that the introduction of an extended auxiliary π-spacer in the donor part is a rational molecular design approach to improve photovoltaic performance by enhancing the light-harvesting ability and hindering charge recombination on the TiO 2 photoanode.