Impacts of Pesticides on Oral Cavity Health and Ecosystems: A Review.

Pesticides are chemical substances used to control, prevent, or destroy agricultural, domestic, and livestock pests. These compounds produce adverse changes in health, and they have been associated with the development of multiple chronic diseases. This study aimed to present a detailed review of the effect of pesticides on the oral cavity and the oral microbiome. In the oral cavity, pesticides alter and/or modify tissues and the microbiome, thereby triggering imbalance in the ecosystem, generating an inflammatory response, and activating hydrolytic enzymes. In particular, the imbalance in the oral microbiome creates a dysbiosis that modifies the number, composition, and/or functions of the constituent microorganisms and the local response of the host. Pesticide exposure alters epithelial cells, and oral microbiota, and disrupts the homeostasis of the oral environment. The presence of pesticides in the oral cavity predisposes the appearance of pathologies such as caries, periodontal diseases, oral cancer, and odontogenic infections. In this study, we analyzed the effect of organochlorines, organophosphates, pyrethroids, carbamates, bipyridyls, and triazineson oral cavity health and ecosystems.

Testing the blast response of foam inserts for helmets.

Modern era combat helmets have different iterations and configurations to offer greater protection from blunt impact or ballistic penetration to suit the theatre of operation, although there are currently no standards for blast protection. Moreover, incorporation of blast protection into the same constrained mass-volume envelope is extremely challenging as there is very little space for a material to absorb or dissipate the shockwave. Foam padding is fitted in contemporary combat helmet designs for comfort and standoff purposes. Examples were subjected to blastwaves generated from an air-driven shocktube, along with open cell polyurethane foam specimens of varying pores per inch and thicknesses to. Whilst the range of samples tested did not afford any superior blast mitigation behaviour over the foam already present in helmets, they exhibited comparable performance with a lower mass. There also appears to be positive correlation between increased mass and increased impulse transmitted through the foam. The literature suggests that multiple mechanisms of damage for blast induced mild Traumatic Brain Injury (bTBI) can be caused by the helmet itself, therefore additional protection from a blunt or ballistic impact may increase the risk of damage from a blast insult.

On differences in the equation-of-state for a selection of seven representative mammalian tissue analogue materials.

Tissue analogues employed for ballistic purposes are often monolithic in nature, e.g. ballistic gelatin and soap, etc. However, such constructs are not representative of real-world biological systems. Further, ethical considerations limit the ability to test with real-world tissues. This means that availability and understanding of accurate tissue simulants is of key importance. Here, the shock response of a wide range of ballistic simulants (ranging from dermal (protective/bulk) through to skeletal simulant materials) determined via plate-impact experiments are discussed, with a particular focus on the classification of the behaviour of differing simulants into groups that exhibit a similar response under high strain-rate loading. Resultant Hugoniot equation-of-state data (Us-up; P-v) provides appropriate feedstock materials data for future hydrocode simulations of ballistic impact events.