PubMed Health⌕ Search
Home/Archive/PubMed

PubMed · 10341689

Radiographic exposure slide rules.

J E Burns
View original source ↗Export metadata ↓

Abstract

Before automatic exposure control was fitted to diagnostic X-ray sets, radiographers were faced with the problem of choosing the parameters that would give the best radiographic image. For a new X-ray set whose performance was unknown, this was no easy matter, and often required considerable trial and error because of the number of variables involved. To reduce the amount of work, special slide rules were invented which calculated the effect of some of these variables. Five such slide rules, dating from between about 1910 and 1950, are illustrated and discussed, including the light they shed on changes in radiographic practice over the years.

Explore related subjects

History, 20th CenturyHumansRadiation DosageRadiographyRadiometryHistorical ArticleJournal Article

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

J E Burns. 1999. Radiographic exposure slide rules.. https://doi.org/10.1259/bjr.72.853.10341689

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

PubMed2026

Addressing racism as a clinical competence: Robert Wilson, Jr. (1867-1946).

Addressing health inequity is now recognized as a clinical competency in medical education. We examined the career and writings of Robert Wilson Jr. (1867-1946), longtime dean of the Medical College of the State of South Carolina during the Jim Crow Era, using primary and secondary sources within the context of systemic and structural racism, particularly in South Carolina. Wilson used public health data to refute the "Black Extinction Hypothesis" rooted in social Darwinism. He challenged assumptions of inherent Black susceptibility to tuberculosis, linking disease instead to social determinants of health. He also identified disproportionate mortality from kidney and cardiovascular disease among Black populations, anticipating modern health disparities research. Wilson further acknowledged systemic injustice and implicated structural conditions, including housing, in shaping outcomes. In an era of continuing health inequity and racial health disparities, Wilson applied empirical evidence to reject biological determinism, identify outcomes disparities, and advocate for racial justice.

History, 20th Century↗
PubMed2024

A Donald F. Hunt Story (John's Version).

A personal narrative of my time in the Hunt laboratory and beyond is provided. The impact of the Hunt laboratory on the analysis of peptides and proteins by tandem mass spectrometry is described in the context of the time.

History, 20th Century↗
PubMed2007

[From the Gestaltkreis to synergetics: irreversible structural and dynamic functional couplings].

With the present contribution, we attempt to merge the work of several generations of physiology and psychosomatics. The common denominator in an array of observation levels appear in these works as the relationship between irreversible-structural and dynamic-functional couplings and synchronisations. In this context, studies on the level of the common brainstem system appear to be the base for a neuro-bio-psychic self-organisation. Studies culled from psychosomatics of Heidelberg, notably the Gestaltkreis theory, the Methodenkreis (methodological loop), the Bipersonalität (bipersonality), and the Simultandiagnostik (simultaneous diagnostics) exhibit the origin of complex functions which have been analyzed and quantified employing nonlinear methods developed in synergetics. Relevance of coupling and synchronisation, desynchronisation, resp., is, however, not limited to the scope of psychosomatic medicine. Fixed or functional, they are essential constituents to neurophysiological processes, such as association, dissociation, resp. This equally holds for evidence based medicine which is to benefit from any dynamic process analysis.

History, 20th Century↗