In Memoriam Benjamin Thomas Hoyt

Memoriam.

Radiobiological and biochemical investigations of polyoma virus-cell interactions

The cytolytic interaction of Polyoma virus with mouse embryo cells has been studied by radiobiological methods known to distinguish temperate from virulent bacteriophage. No evidence for "temperate" properties of Polyoma was found. During the course of these studies, it was observed that the curve of inactivation of Polyoma virus by ultraviolet light had two components - a more sensitive one at low doses, and a less sensitive one at higher doses. Virus which survives a low dose has an eclipse period similar to that of unirradiated virus, while virus surviving higher doses shows a significantly longer eclipse period. If Puromycin is present during the early part of the eclipse period, the survival curve becomes a single exponential with the sensitivity of the less sensitive component. These results suggest a repair mechanism in mouse cells which operates more effectively if virus development is delayed.

A comparison of the rates of inactivation of the cytolytic and transforming abilities of Polyoma by ultraviolet light, X-rays, nitrous acid treatment, or the decay of incorporated P³², showed that the transforming ability has a target size roughly 60% of that of the plaque-forming ability. It is thus concluded that only a fraction of the viral genes are necessary for causing transformation.

The appearance of virus-specific RNA in productively infected mouse kidney cells has been followed by means of hybridization between pulse-labelled RNA from the infected cells and the purified virus DNA. The results show a sharp increase in the amount of virus-specific RNA around the time of virus DNA synthesis. The presence of a small amount of virus-specific RNA in virus-free transformed cells has also been shown. This result offers strong evidence for the persistence of at least part of the viral genome in transformed cells.

Tomb of Cicero [Material gráfico]

Inscripción en la parte inferior: "Plate 47"

The summit and Crater of Mount Vesuvius [Material gráfico]

Inscripción en la parte inferior: "Plate 60"

Ausfürliche Abhandlung Kuhpocken ... /

Mode of access: Internet.

Memoir of John Woolman, chiefly extracted from a journal of his life and travels ...

Mode of access: Internet.

A voyage of discovery to the North Pacific Ocean, and round the world : in which the coast of north-west America has been carefully examined and accurately surveyed : Undertaken by His Majesty's command, principally with a view to ascertain the existence of any navigable communication between the North Pacific and North Atlantic Oceans, and performed in the years 1790, 1791, 1792, 1793, 1794, and 1795, in the Discovery sloop of war, and armed tender Chatham, under the command of Captain George Vancouver : in three volumes, Vol. III.

Mode of access: Internet.

A voyage of discovery to the North Pacific Ocean, and round the world : in which the coast of north-west America has been carefully examined and accurately surveyed : Undertaken by His Majesty's command, principally with a view to ascertain the existence of any navigable communication between the North Pacific and North Atlantic Oceans, and performed in the years 1790, 1791, 1792, 1793, 1794, and 1795, in the Discovery sloop of war, and armed tender Chatham, under the command of Captain George Vancouver : in three volumes, Vol. II.

Mode of access: Internet.

Selectæ e profanis scriptoribus historiæ : quibus admista sunt varia honeste vivendi præcepta, ex iisdem scriptoribus deprompta.

Mode of access: Internet.

The original, and present state of man, briefly considered; : wherein is shewn, the nature of his fall, and the necessity, means, and manner of his restoration, through the sacrifice of Christ, and the sensible operation of the divine principle of grace and truth, held forth to the world by the people called Quakers. : To which are added, some remarks on the doctrine of predestination, the scriptures, worship, and the kingdom of heaven. /

Smith, J. Friends' books

Elizabeth Engel nee Benjamin-Rasmussen in her home; Silver Springs, Maryland Portraits Women

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Elizabeth Engel nee Benjamin-Rasmussen with her daughter Dorel Hall nee Engel in Elizabeth's home; Silver Springs, Maryland Portraits Family

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Joseph Molling with wife Margarete "Gretchen" nee Benjamin and son Peter on a walk.

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Portrait of Hedwig and Ludwig Heinemann and Margarete nee Benjamin and Joseph Molling.

Elderly couple Hedwig and Ludwig Heinemann envolved with Adolph Molling Business. Younger couple is Margarete "Gretchen" Molling geb. Benjamin and Joseph Molling.