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Viruses may represent the most diverse microorganisms on Earth. Novel viruses and variants continue to emerge. Mosquitoes are the most dangerous animals to humankind. This study aimed at identifying viral RNA diversity in salivary glands of mosquitoes captured in a sylvatic area of Cerrado at the Chapada dos Guimarães National Park, Mato Grosso, Brazil. In total, 66 Culicinae mosquitoes belonging to 16 species comprised 9 pools, subjected to viral RNA extraction, double-strand cDNA synthesis, random amplification and high-throughput sequencing, revealing the presence of seven insect-specific viruses, six of which represent new species of Rhabdoviridae (Lobeira virus), Chuviridae (Cumbaru and Croada viruses), Totiviridae (Murici virus) and Partitiviridae (Araticum and Angico viruses). In addition, two mosquito pools presented Kaiowa virus sequences that had already been reported in South Pantanal, Brazil. These findings amplify the understanding of viral diversity in wild-type Culicinae. Insect-specific viruses may present a broader diversity than previously imagined and future studies may address their possible role in mosquito vector competence.

Positive moods are thought to restore self-control resources following depletion. However, it is not well understood whether this effect is due to affective valence (pleasantness), arousal (activation), or a combination of both. Across four studies, we set out to investigate the role of positive moods on cognitive and behavioral measures of self-regulation in an ego-depletion paradigm. In studies 1 and 2, we independently manipulated affective valence and arousal and assessed self-regulation with a Stroop task. Results did not suggest a restorative effect of either on cognitive resources. In study 3, we employed both behavioral (the 'handgrip task') and cognitive (Stroop) assessments of self-regulation. Again, no significant effect of mood was observed on the Stroop task. Additionally, participants did not persist significantly longer on the handgrip task following a positive mood induction. Finally, in study 4, high vs. low states of arousal were manipulated and self-regulation was assessed via pre- and post-manipulation Stroop performance. In study 4, Stroop performance improved slightly more across time points for those in the high arousal condition than for those in the low arousal condition. Therefore, across four studies, we failed to find a consistent pattern of results suggesting that positive moods restore cognitive resources.

Mutation or loss of collagen VI has been linked to a variety of musculoskeletal abnormalities, particularly muscular dystrophies, tissue ossification and/or fibrosis, and hip osteoarthritis. However, the role of collagen VI in bone and cartilage structure and function in the knee is unknown. In this study, we examined the role of collagen VI in the morphology and physical properties of bone and cartilage in the knee joint of Col6a1(-/-) mice by micro-computed tomography (microCT), histology, atomic force microscopy (AFM), and scanning microphotolysis (SCAMP). Col6a1(-/-) mice showed significant differences in trabecular bone structure, with lower bone volume, connectivity density, trabecular number, and trabecular thickness but higher structure model index and trabecular separation compared to Col6a1(+/+) mice. Subchondral bone thickness and mineral content increased significantly with age in Col6a1(+/+) mice, but not in Col6a1(-/-) mice. Col6a1(-/-) mice had lower cartilage degradation scores, but developed early, severe osteophytes compared to Col6a1(+/+) mice. In both groups, cartilage roughness increased with age, but neither the frictional coefficient nor compressive modulus of the cartilage changed with age or genotype, as measured by AFM. Cartilage diffusivity, measured via SCAMP, varied minimally with age or genotype. The absence of type VI collagen has profound effects on knee joint structure and morphometry, yet minimal influences on the physical properties of the cartilage. Together with previous studies showing accelerated hip osteoarthritis in Col6a1(-/-) mice, these findings suggest different roles for collagen VI at different sites in the body, consistent with clinical data.