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Human adenoviruses (HAdVs) are highly contagious pathogens with various genotypes implicated in acute respiratory disease (ARD) and linked to mortality, especially in immunosuppressed patients, young children, and military recruits. Currently, no vaccines or specific drugs are approved for clinical use. The hosts of adenoviruses are strictly species-specific, which strongly limits the development of vaccines and drugs against HAdVs. In this study, immunocompetent BALB/c mice were challenged with different doses of human adenovirus type 5 (HAdV-5) via tail intravenous injection (i.v.). All mice challenged with a high dose of HAdV-5 (3.2×1010TCID50/kg) died within 3 to 5 days, while those receiving a low dose of HAdV-5 (8×109or 4×109TCID50/kg) survived. Interestingly, among the mice receiving a medium dose of HAdV-5 (1.6×1010TCID50/kg), 60% (n = 3/5) of male mice died, while all female mice survived. This suggests that male mice may be more susceptible to HAdV-5 infection than female mice, consistent with clinical findings in children. HAdV-5 DNA was mainly distributed in the liver, followed by the spleen and lungs. Pathological changes were observed in the lungs, liver, and spleen, with severity increasing in correlation with the virus challenge dosage. Transcriptome and qPCR analyses of the liver indicated that the down-regulated expression of the H2-Aa, H2-Ea-ps, CD74, and H2-Eb1genes in male mice, as well as the AHRgene in female mice, may contribute to the observed higher mortality rates in male mice. Therefore, this effective, feasible, and cost-efficient mouse model could serve as a candidate for evaluating HAdV vaccines and anti-adenovirus therapeutics.

The solid solution series Bi2V1-xMnxO 5.5-x(0.10≤x≤0.25) has been prepared by conventional solid-state reaction and by crystallization from the melt. After additional subsolidus annealing both procedures yielded tetragonal phases with similar structures and lattice constants, as determined by X-ray powder diffraction. Partial substitution of manganese on the vanadium sites stabilizes Bi2V1-x MnxO5.5-xin the high-temperature tetragonal (γ) structure of Bi2VO5.5 for compositions in the range 0.10≤x ≤0.25. The structures of four compositions have been investigated by combined Rietveld refinements of X-ray and neutron powder diffraction data. Further characterization studies by transmission electron microscopy, magnetic susceptibility measurements and differential thermal analysis are described.

The total electrical conductivities of a series of manganese-substituted bismuth vanadates, (Bi2V1-xMnxO 5.5-x; 0.15≤x≤0.25) with the tetragonal (γ) structure have been measured using two-probe ac impedance spectroscopy. The conductivity data do not show simple Arrhenius behaviour. A linear variation of log(σT)vs. 1/Tis observed at low and high temperatures but at intermediate temperatures some curvature is apparent in the data, particularly whenx=0.2. Changes in conductivity with p(O2) indicate that the materials have mixed conductivity. Activation energies and pre-exponential factors for the linear regions have been determined for selected compositions at various p(O2) values. The total conductivity varies little with the extent of substitution of V by Mn. The results are compared with data for other γ-BIMEVOX systems.