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Biomedical subjects

W H Hughes

Publications and source records attributed to W H Hughes.

16 recordsLinked to original sources
PubMed2000

Asynchronous, irregular automata nets: the path not taken.

This is a prelude to, and an extension of the original paper Artificial tissue models (Stark, R., 1994. The topology and analysis of asynchronous processes. http://www.math.usf.edu/ approximately stark/documents). However, this exposition is designed for a broader audience - anyone working in biological information processing. A primary objective is to demonstrate that irregular asynchronous automata nets, as opposed to cellular automata, are a realistic approach to modeling biological information processing. Also, new material is presented. Sections 1 and 2 review the early history of von Neumann's attempt explore biological information processing and finally the emergence of cellular automata. The history is guided by the question of why John von Neumann knowingly (we believe) compromised his investigation of biological information processing by falling back to the model we now know as cellular automata. Section 3 defines and explores examples of cellular automata and artificial tissue. Sections 4 and 5 contain philosophical observations which unify our paper, and propose an answer to the original question. A new model for Turing's leopards' spot problem is presented. The asynchronous models are defined by a cell program and a local commumications protocol only. Computational freedom comes from asynchronous activity, while global organization emerges from the entropy reducing nature of the cell programs.

Cells↗
PubMed1986

Superovulation and embryo transfer in the dairy goat.

Eighteen mature, purebred (Saanen, Alpine, Nubian, La Mancha) dairy does were estrus-regulated with progesterone-impregnated vaginal pessaries. On treatment days 16 to 18, superovulation of 6 does was attempted with pregnant mare's serum gonadotropin (PMSG), and of 12 does with follicle stimulating hormone (FSH). Estrus was induced by progesterone withdrawal on days 18 to 20 and the does were mated to bucks of proven fertility. Embryos were recovered from oviduct flushings on the fourth day after mating. The yield of 4- to 12-cell embryos with FSH superovulation was 17(+/- 2), significantly greater (P less than 0.001) than with PMSG, which was 2(+/- 2). Thirty-six embryos from 3 FSH donor does were transferred to 14 recipients that were estrus-regulated to the donor cycles with the same progesterone pessary regimen. Eleven (78%) of the recipients became pregnant and delivered 21 (70%) kids from 40 embryos, a mean of 7(+/- 2)/donor.

Animals↗
PubMed1970

The irreducible minimum in cross-infection control and isolation nursing.

This is a survey of 10 years experience in trying to find out how to control hospital sepsis economically. We appear to have obtained reasonable improvements in hygiene by applying the teaching which has been given to students since the time of Leonard Colebrook. For our investigations we used only routine methods.The order of importance of the factors in reducing cross-infection would appear to be: (1) single rooms for all septic cases and for those requiring protective isolation; (2) a sister supported in complete authority over anyone entering the unit; (3) a simple, inflexible drill to introduce an impermeable layer between the nurse or doctor and the patient-gloves and apron provide this; (4) overshoes and barrier mats; (5) hygienic disposal of linen; (6) an efficient wet dusting and floor cleaning system. Anything beyond this must be justified by saving of nursing time or some factor other than prevention of infection.

Anesthesiology↗
PubMed1968

Antibiotics.

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Anti-Bacterial Agents↗