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Biomedical subjects

A P Makepeace

Publications and source records attributed to A P Makepeace.

11 recordsLinked to original sources
PubMed2001

Use of capillary gas chromatography with negative ion-chemical ionization mass spectrometry for the determination of perfluorocarbon tracers in the atmosphere.

A sensitive and selective technique for the quantitative measurement of atmospheric perfluorocarbon trace species at the sub part per quadrillion (10(-15)) levels is presented. The method utilizes advances in adsorbent enrichment techniques coupled with benchtop capillary gas chromatography and negative ion-chemical ionization mass spectrometry. The development and enhancement of sampling technology for tracer experiments is described, and the results from background measurements and a preliminary field experiment are presented. The overall precision of the analytical method with respect to the preferred tracer for these atmospheric transport studies, perfluoromethylcyclohexane, was +/-1.7%. The background concentrations of perfluorodimethylcyclobutane, perfluoromethylcyclopentane, and perfluoromethylcyclohexane at a remote coastal location (Mace Head, Ireland, 53 degrees N, 10 degrees W) were found to be 2.5 (+/-0.4), 6.8 (+/-1.0), and 5.2 fL L(-1) (+/-1.3), respectively. Background concentrations within an urban conurbation (Bristol, U.K.) were slightly greater at 3.0 (+/-1.5), 8.1 (+/-1.8), and 6.3 fL L(-1) (+/-1.1), respectively.

Air Pollutants, Occupational↗
PubMed1982

Some characteristics of endoscopic and radiological systems used in elaboration of the diagnosis of velopharyngeal incompetence.

The characteristics of rigid and flexible endoscopes have been studied with reference to their suitability for nasal pharyngoscopy in the assessment of velopharyngeal incompetence taking into account a number of fallacies which are known to exist. It is concluded that the ability to achieve correct positioning of the rigid endoscope and the wide angle field of view of the 70 degrees Storz-Hopkins nasopharyngoscope, in particular, made it the best single instrument at present available for this work despite the greater ease of introduction of the flexible endoscopes. The characteristics of the information obtained by radiological examination were studied and in comparison with endoscopic information it was concluded that endoscopic information was more reliable for qualitative and radiological for quantitative analysis. The systems were considered to be mutually complementary and simultaneous examination with, preferably, synchronous recording provided the advantages of optimal placement of the endoscope and the possibility of measurement of the velopharyngeal isthmus.

Barium Sulfate↗
PubMed1977

An optoelectronic slide identifier.

An inexpensive optoelectronic slide identifier that uses binary code is described. It can be attached to most automatic projectors and provides for automatic indexing of up to two-hundred and fifty-five different coded slides, while each slide is being projectd.

Abstracting and Indexing↗
PubMed1977

Operating microscope eyepiece heaters.

Precipitation of water vapour from expired air on to exposed eyepiece lenses of operating microscopes can seriously interfere with the surgeon's view. By warming these optical surfaces to temperatures well above the dew point of expired air this problem is eliminated. A pair of small heaters were designed to clamp over the eyepiece tubes of a standard operating microscope and their effectivity assessed.

Heating↗
PubMed1976

Resuscitation teaching room in a district general hospital: concept and practice.

Practical training in cardiopulmonary resuscitation presents a problem because of the shortage of teacher time and the many potential trainees. A resuscitation teaching room in district general hospital has been established, equipped with training mannikins and models, together with wall diagrams and cassette recordings. The arrangement enables many trainees to gain training in small groups with minimal demand on teachers. Experience with the room in use has suggested that the concept may have an application in many district general hospitals and possibly also in large industrial concerns.

Allied Health Personnel↗
PubMed1975

The technique of recording nasal pharyngoscopy.

Nasal pharyngoscopy is a relatively simple and most informative technique requiring a small amount of very portable equipment. Recording the observations objectively is of considerable clinical and research value, but will require a two-man team, one of whom must be thoroughly versed in audio-visual communication techniques and apparatus. The equipment is more expensive and although it can be transported is probably best used at a routine site.

Anesthesia, Local↗