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Bovine viral diarrhea virus (BVDV) is one of the most important etiological agents that causes serious economic losses to the global livestock industry. Vaccines usually provide limited efficacy against BVDV due to the emergence of mutant strains. Therefore, developing novel strategies to combat BVDV infection is urgently needed. Bergamottin (Berg), a natural furanocoumarin compound, possesses various pharmaceutical bioactivities, but its effect on BVDV infection remains unknown. The present study aimed to investigate the antiviral effect and underlying mechanism of Berg against BVDV infection. The results showed that Berg exhibited an inhibitory effect on BVDV replication in MDBK cells by disrupting the viral replication and release, rather than directly inactivating virus particles. Mechanistically, Berg inhibits BVDV replication by suppressing endoplasmic reticulum (ER) stress-mediated apoptosis via reducing reactive oxygen species (ROS) generation. Studies in vivo demonstrated that oral gavage of Berg at doses of 50 mg/kg and 75 mg/kg significantly reduced the viral load within the intestines and spleen in BVDV-challenged mice. Furthermore, histopathological damage and oxidative stress caused by BVDV were also mitigated with Berg treatment. Our data indicated that Berg suppressed BVDV propagation both in vitro and in vivo, suggesting it as a promising antiviral option against BVDV. [ABSTRACT FROM AUTHOR]

A two‐step hydrothermal method is used to produce Fe3O4/CuS composites with a distinct layered structure of CuS. The composition, magnetism, and absorbing properties of the different proportions of Fe3O4/CuS composites are characterized. The results show that Fe3O4 absorbs electromagnetic waves through orientation polarization and magnetically related natural resonance and that high conductivity enhances CuS microwave absorption. Compared with single‐phase Fe3O4 and CuS, Fe3O4/CuS composites exhibit superior microwave absorption performance with a considerably reduced matching thickness and increased effective absorption bandwidth in the 1–18 GHz range, which can be attributed to the interfacial coupling‐induced polarization between heterostructure Fe3O4 and CuS. Based on these results, Fe3O4/CuS composites can be absorbers with a far wider microwave‐effective absorption bandwidth. [ABSTRACT FROM AUTHOR]

Fe3O4 was synthesized by the hydrothermal method in one step. The grain size, morphology, and microwave absorption performances were modified effectively by heat treatment in a vacuum environment at different temperatures. Compared with the Fe3O4 before annealing, the minimum reflection loss value of Fe3O4 after annealing at 850 °C reaches − 27.5 dB at a thickness of 1.6 mm, with the effective absorption band reaching 5.68 GHz (10.32 GHz to 16 GHz). This result is due to the emergence of the second-phase Fe2O3 in Fe3O4 after annealing at 850 °C. The interfacial coupling between Fe3O4 and Fe2O3 leads to additional polarization. Moreover, the considerable absorption bandwidth resulted from better impedance matching and excellent attenuation performance. Therefore, it has broad application prospects as a microwave absorber. [ABSTRACT FROM AUTHOR]

Thermal stability of written bits on [MgO xnm/FePt ynm]a/MgO4-nm/Si[O.sub.2] 4-nm/Fe-Ta-C 200-nm/Glass perpendicular media with two different structure having different stability factor has been investigated by magnetic force microscopy (MFM) equipped with in-situ sample heating system up to 200 [degrees]C. The disk with x = 2 nm, and y = 2.5 nm, shows no observable degradation even at 200 [degrees]C, indicating high thermal stability of this disk. On the other hand, for the disk with a: = 4 nm, and y = 3 nm, some reversed domains are observed in the center area of 10 kfci bits at 200 [degrees]C and some minor changes are found in the transition area of the higher frequency bits. The decay at a higher temperature is interpreted in terms of estimated thermal stability factor from MFM signal decay. Index Terms--FePt, magnetic anisotropy, magnetic force microscopy (MFM), perpendicular magnetic recording media, thermal stability.

Double-layered perpendicular magnetic recording media, composed of granular-type FePt-MgO films on Fe-Ta-C soft magnetic underlayer, are fabricated on to 2.5-in glass discs with the stack structure of [[MgO x-nm/FePt y-nm].sub.n]/MgO 4-nm/Si[O.sub.2] 4-nm/Fe-Ta-C 200-nm/Glass disk. After annealing, granular films of FePt-MgO with high perpendicular magnetic anisotropy of the order of 106 erg/cc and with the texture (001) along the film normal can be successfully fabricated. The perpendicular coercivity, magnetic activation volume, and the exchange coupling between the FePt grains are found to be strongly dependent on the initial multilaver structures and the optimum annealing conditions. The recording performance of the double-layered disks is evaluated by a spin-stand. The obtained results reveal a close correlation between the recording performance and magnetic properties. Index Terms--FePt, granular-type structure, magnetic anisotropy, perpendicular magnetic recording media, recording performance.

The exchange coupling and magnetic properties distributions in Co/Pd multilayer perpendicular magnetic anisotropy films with different magnetic properties are investigated using the experimental first order reversal curve (FORC) diagram with assistance of Landau–Lifshitz–Gilbert simulation. The simulated FORC diagrams of perpendicular magnetic anisotropy films with different exchange couplings and magnetic property distributions are quite different, which make FORC diagrams very powerful for characterizing perpendicular magnetic recording media. [ABSTRACT FROM AUTHOR]

The ac susceptibility, electrical properties, and magnetotransport properties of the as-prepared MnxCu1-xO thin films (x=7%–29%) were studied in the temperature range of 2–300 K. The susceptibility measurement shows that ferromagnetic transition takes place for the samples with x≥14% below 100 K. The transport properties show the transition from variable-range-hopping to metalliclike behavior at the same transition temperature as the paramagnetism to ferromagnetism transition. The metal-insulator transition is a characteristic feature of magnetic ordering in this material. [ABSTRACT FROM AUTHOR]

There is a need to identify and select new promising immunodominant antigens that have the ability to provide protective immunity against E. coli causing bovine mastitis. Recently we showed that f17a was found to be the most prevalent and crucial virulent factor among the pathogenic E. coli isolated from bovine mastitis. Here, in this report, the recombinant F17A based subunit vaccine adjuvant with MF59 was tested for immunogenicity against E. coli in a murine model. The vaccinated mice did not show any abnormal behavioral changes and histopathological lesions after vaccination. The specific antibody level against F17A was significantly higher in MF59-adjuvant-group, and also lasted for longer duration with a significant (P<0.01) production level of IgG1 and IgG2a. Moreover, we noted higher survival rate in mice injected with F17A-MF59-adjuvant group after challenging with the clinical E. coli strain. Our findings of bacterial clearance test revealed that elimination rate from liver, spleen, and kidney in MF59-adjuvant-group was significantly higher than the control group. Finally, the proportion of CD4+T cells was increased, while CD8+ was decreased in MF59-adjuvant group. In conclusion, the current study reveals the capability of F17A-MF59 as a potential vaccine candidate against pathogenic E. coli causing mastitis in dairy animals. [ABSTRACT FROM AUTHOR]