A speculum of chymical practice: Isaac Newton, Martin Lister (1639 −1712), and the making of telescopic mirrors

In 1674 the natural philosopher and physician Martin Lister published a new method of making glass of antimony for telescopic mirrors, using Derbyshire cawk or barite as a flux. New manuscript evidence reveals that Sir Isaac Newton requested samples of the cawk and antimony from Lister through an intermediary named Nathaniel Johnston. An analysis of Lister’s paper and Johnston’s correspondence and its context reveals insights not only about Newton’s work with telescopic specula but also about his alchemical investigations. Analysing these sources also contributes to our understanding of the nature of correspondence networks in the early ‘scientific revolution’ in England

The correspondence of Dr. Martin Lister (1639-1712) [Volume One 1662-1677]

Martin Lister (1639–1712) was a consummate virtuoso, the first arachnologist and conchologist, and a Royal physician. As one of the most prominent corresponding fellows of the Royal Society, many of Lister’s discoveries in natural history, archaeology, medicine, and chemistry were printed in the Philosophical Transactions. Lister corresponded extensively with explorers and other virtuosi such as John Ray, who provided him with specimens, observations, and locality records from Jamaica, America, Barbados, France, Italy, the Netherlands, and his native England. This volume of ca. 400 letters (one of three), consists of Lister’s correspondence dated from 1662 to 1677, including his time as a Cambridge Fellow, his medical training in Montpellier, and his years as a practicing physician in York

The Saline chymistry of color in seventeenth-century English natural history

Before Newton’s seminal work on the spectrum, seventeenth-century English natural philosophers such as Robert Boyle, Robert Hooke, Nehemiah Grew and Robert Plot attributed the phenomenon of color in the natural world to salts and saline chymistry. They rejected Aristotelian ideas that color was related to the object’s hot and cold quali- ties, positing instead that saline principles governed color and color changes in flora, fauna and minerals. In our study, we also characterize to what extent chymistry was a basic analytical tool for seventeenth-century English natural historians

The chymistry of "The Learned Dr Plot" (1640-96)

In the seventeenth century, there were developing norms of openness in the presentation of scientific knowledge that were at odds with traditions of secrecy among chymists, particularly practitioners of chrysopoeia, or the transmutation of metals. This chapter analyzes how Dr. Robert Plot, the first professor of chymistry at Oxford, negotiated these boundaries within an institutional context. I first delineate his chymical and experimental practice, which incorporated procedures from medieval alchemical sources, particularly the Lullian corpus, as well as more novel practices from seventeenth-century chymistry. Then, I analyze how personal and institutional ambitions and economic considerations shaped to what extent Plot negotiated the boundaries between secrecy and the public dissemination of chymical knowledge

Newton and the apothecary

The Grantham Corporation Minute Books and inventories from the apothecary shop of Ralph and William Clarke are analysed to illuminate neglected aspects of the life and letters of Sir Isaac Newton, particularly the influence of Lincolnshire social and intellectual networks. The article also examines the nature of rural health provision in early modern Grantha

Pathways of NHEJ at Dysfunctional Telomeres and Their Resolution

Shelterin is a multiprotein complex that prevents DNA damage signaling at chromosome ends. In its absence, DNA repair pathways are activated that can promote the fusion of dysfunctional telomeres resulting in chromosomal instability. The work presented here aims to understand how telomeres are protected from these pathogenic repair pathways. The first part of this thesis is focused on the DNA damage response factor 53BP1, a key regulator in double strand break (DSB) repair pathways in mammalian cells. By influencing key regulatory events at and near DNA ends, 53BP1 plays an important role in the decision between non-homologous endjoining (NHEJ) and homologous recombination (HR). Telomeres lacking the shelterin protein TRF2 have proven a versatile system for studying 53BP1 in DSB repair since 53BP1 protects dysfunctional telomeres from resection and promotes their mobility. Analysis of separation of function mutants of 53BP1 has identified the domain that is responsible for promoting the mobility of DSBs. Cells expressing 53BP1ΔMOB showed reduced levels of NHEJ at dysfunctional telomeres and damage foci roamed a smaller part of the nucleus. But which 53BP1 interacting factors are responsible for mediating the increased mobility remains unclear. The second part of this thesis aims to elucidate the DNA repair pathways that are activated when the shelterin component TRF1 is absent. The results provide tantalizing evidence that sister telomeres can fuse via the alternative- NHEJ (a-NHEJ) pathway when replication forks reach the end of the chromosome in cells that are deficient in TRF1. To prevent chromosome instability, mammalian cells appear to employ the Holliday Junction resolvase Gen1, which is capable of cleaving cruciform DNA structures that can be formed when telomeres fuse. The deletion of Gen1 from TRF1 null cells resulted in the accumulation of chromatin bridges and isochromosomes, indicative of genomic instability. The results presented here are of relevance to studies of human cancer cells since the presence of critically short telomeres induces sister telomere fusions via a-NHEJ. It is possible that replication stress underlies these fusion events and that Gen1 has evolved as a mechanism to counteract the consequences of chromosomal fusion events at telomeres

Johann Heinrich Cohausen (1665–1750), Salt Iatrochemistry, and Theories of Longevity in his Satire, Hermippus Redivivus (1742)

Johann Heinrich Cohausen (1665–1750) was a physician and well-known author in the Germanies, France, and England He was best known for medical satire such as the Pica Nasi, a Latin parody on snuff in which Apollo ordered Mercury to confiscate the noses of snuff-takers. When the satyrs returned them, the desperate victims grabbed the wrong noses and were unrecognizable. The subject of this article however is Cohausen’s last and most famous medical satire, his Hermippus redivivus (1742), a treatise on the prolongation of life. Studies of Cohausen and the Hermippus have been largely antiquarian; the only scholarly works are a French dissertation concerning his medical biography done in 1900 and a short German bibliographic study. Because Cohausen has been primarily known for medical satire, his large number of serious treatises on iatrochemistry and medicine, which served as the basis for his more humorous works, have been largely unexamined. This paper will thus demonstrate that Cohausen’s Hermippus and its comedic presentation of longevity had a profound reliance on earlier scholarly works of his that analysed the theories of the seventeenth-century chymist and physician Jean Baptiste van Helmont (1577–1634)

Brown bears behavioral response to dog training : how bears (Ursus arctos) in enclosures react to dog training

Dog training and testing on bears (Ursus arctos) occurs both on bears in the wild and bears in enclosures. In Sweden the main way of hunting bears is with dogs and the main cause of death of bears in Sweden is due to legal hunting. Today, to my knowledge, no research has been done on how bears in enclosures are affected by dog training. The aims of the present study were to investigate if bears show any behavioural signs of stress during dog training, if the training can be considered as enriching for the bears and if the bears’ behavioural response alters with the number of training episodes during the day and between training days. During dog training the bears at this training facility were kept in a test enclosure connected to their main enclosure. The bears were exposed to one dog at a time which is allowed to roam freely outside the test enclosure and bay and bark at the bears. Results showed that the bears’ response to dog training differs between individuals and that the dog training could be perceived as stressful for the bears. The bears displayed natural behaviours such as exploring and social interactions on all days of training, where social interactions mainly consisted of body contact. Behaviours related to stress such as charging towards the dog and moving away from the dog were shown by all individuals and pacing was exhibited by one of the bears. Social interactions such as playing was shown by two individuals once, but other behavioural responses did not indicate the dog training as a positive experience or as enriching for the bears. The behavioural response differed between number of practices and individuals but could not distinguish any behavioural patterns in the group. One of the bears showed pacing behaviour on the fourth training occasion of the day and two bears showed charging towards dog on the first observation of the day. This indicates that there are individual differences between the bears at this training facility. In conclusion, this study provided a picture of bears behavioural responses during dog training. Some of these behaviours were consistent with stress. Results from more comprehensive behavioural studies, completed with physiological data, would provide additional information on the welfare of these bears