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Heterogeneity of COVID-19 manifestations in human population is vast, for reasons unknown. Cotton rats are a clinically relevant small animal model of human respiratory viral infections. Here, we demonstrate for the first time that SARS-CoV-2 infection in cotton rats affects multiple organs and systems, targeting species- and age-specific biological processes. Infection of S. fulviventer, which developed a neutralizing antibody response and were more susceptible to SARS-CoV-2 replication in the upper respiratory tract, was accompanied by hyperplasia of lacrimal drainage-associated lymphoid tissue (LDALT), a first known report of mucosa-associated lymphoid tissue activation at the portal of SARS-CoV-2 entry. Although less permissive to viral replication, S. hispidus showed hyperplasia of bone marrow in the facial bones and increased pulmonary thrombosis in aged males. Augmentation of these features by SARS-CoV-2 infection suggests a virus-induced breach in regulatory mechanisms which could be devastating for people of all ages with underlying conditions and in particular for elderly with a multitude of ongoing disorders.

The new ballistic tests on different glasses and/or at different projectile velocities have led to interesting considerations. The results of the impulsive tests have been the expected ones, while the ballistic test results, not always the expected ones, have given useful information. When the sandwich 22 mm thick is hit by the projectile at 360 km/h velocity, the whole sandwich (different from the 28 mm one), is involved in the impact phenomenon and thus, the whole sandwich adsorbs the impact energy; this behavior must be considered by the designers and by the purchasers. When the new multilayer 28 mm sandwich is hit by the projectile at 460 km/h velocity, the different macroscopic and local behaviors (with regard to the previous 28 mm one), can help to understand the impact phenomena: as the velocity increases, the involved area decreases, the crater gets deeper, the stiffness of the involved area gets higher.

Until the present moment, only a scarce number of Latin American domestic cat populations have been studied from a population genetic standpoint. For this reason, the cat populations of La Havana (Cuba), San Jose (Costa Rica), Bogota and Ibague (Colombia), Asuncion (Paraguay), Santiago (Chile) and Buenos Aires (Argentina) were sampled for several coat genes. The results obtained were as follows: (1) there was a strong genetic resemblence between several Hispanic American cat populations (especially, those of Buenos Aires, San Jose and the two Colombian populations studied) and those from South Western United States (California, Texas and Colorado), which adds suport to the suspicion that these populations probably have a common origin; (2) The cat population of Santiago (Chile), contrarily to the other Hispanic American populations studied, showed a strong genetic resemblance with some Anglo North American populations; and (3) The I (long hair) and d(dilution) alleles showed systematic higher frequencies in the Hispanic American populations than those observed in Spain. Although the Hispanic American populations were not identical to the current Spanish populations (with the exception of Asuncion), this historic genetic experiment was very different to that found for the British populations and their overseas colonies.

The sandwich glass ballistic test shows some repetitive phenomena. There is a crater surrounded by a plasticized area with a flexural behavior. In the panel central area there is an energy storage and a following energy discharge; out of the central impact area the energy storage is negligible and there is a draw behavior; there is also a panel stiffening. The question is now how to use these results. New tests on the same panel would not add anything to what known so far. But the same kind of tests on different panels makes it possible to compare the different panel behaviors not only from a global point of view, but also from a local point of view. The measurement of the maximum acceleration and strain peaks, of the area interested by the energy storage and discharge, of the panel stiffening after the impact, can give useful directions for the design to the manufacturers, and for the choice of a most apt sandwich glass to the purchasers (the Italian Railroad).

The tests demonstrated that when the strain gages are applied in the manner described in this paper, satisfactory results can be expected. The thermal coefficients of expansion obtained from the apparent strains are reliable for the temperature ranges tested. Thermal drift is small enough to be neglected. Mechanical hysteresis and creep are due to the sandwich glass panel construction, and not due to gage type or installation. Finally, it was demonstrated that the gage type and installation method are suitable for dynamic impact tests which can lead to improved sandwich type windshield panels.

Background Subspecies B1 human adenoviruses (HAdV-B1) are prevalent respiratory pathogens. Compared to their species C (HAdV-C) counterparts, relatively little work has been devoted to the characterization of their unique molecular biology. The early region 3 (E3) transcription unit is an interesting target for future efforts because of its species-specific diversity in genetic content among adenoviruses. This diversity is particularly significant for the subset of E3-encoded products that are membrane glycoproteins and may account for the distinct pathobiology of the different human adenovirus species. In order to understand the role of HAdV-B-specific genes in viral pathogenesis, we initiated the characterization of unique E3 genes. As a continuation of our efforts to define the function encoded in the highly polymorphic ORF E3-10.9K and testing the hypothesis that the E3-10.9K protein orthologs with a hydrophobic domain contribute to the efficient release of viral progeny, we generated HAdV-3 mutant viruses unable to express E3-10.9K ortholog E3-9K and examined their ability to grow, disseminate, and egress in cell culture. Results No differences were observed in the kinetics of infected cell death, and virus progeny release or in the plaque size and dissemination phenotypes between cells infected with HAdV-3 E3-9K mutants or the parental virus. The ectopic expression of E3-10.9K orthologs with a hydrophobic domain did not compromise cell viability. Conclusions Our data show that despite the remarkable similarities with HAdV-C E3-11.6K, HAdV-B1 ORF E3-10.9K does not encode a product with a “death-like” biological activity.