Biomedical subjects

B Linehan

Publications and source records attributed to B Linehan.

4 recordsLinked to original sources

PubMed2003

Hand rolling cigarette papers as the reference point for regulating cigarette fire safety.

AIM: To compare the burning characteristics of the tobacco and paper of manufactured and hand rolled cigarettes, and set a fire safety standard of manufacture to largely reduce the fire risk from discarded cigarettes. METHODS: (1) Cigarette extinction test of ignition strength: 40 cigarettes per brand, lit and placed on 15 layers of filter paper, in accordance with ASTM test standard E2187-02. (2) Citrate extracted by 0.1N hydrochloric acid from cigarette papers and from tobacco in manufactured cigarettes, the supernatant analysed by high performance liquid chromatography using ultraviolet visual light spectrophotometer. (3) Survey of 750 nationally representative adults age 18 years and over, by telephone, including 184 smokers. MATERIALS: (a) New Zealand made Holiday, and Horizon, and US made Marlboro manufactured cigarettes; (b) US manufactured Merit with banded paper; (c) Holiday, Horizon and Marlboro hand rolling tobaccos, hand rolled in Rizla cigarette papers; (d) manufactured cigarettes as in (a), reconstructed using Rizla hand rolling cigarette papers. RESULTS: 1. (a) For each brand of manufactured cigarettes, 40/40 burnt full length; (b) for Merit banded paper cigarettes 29/40 (73%) burnt full length; (c) for each brand of hand rolled cigarettes 0/40 burnt full length; (d) 0/40 manufactured cigarettes reconstructed with Rizla hand rolling paper burnt full length. 2. Citrate content: (a) In manufactured cigarette papers: 0.3-0.8 mg; in tobacco of manufactured cigarettes: Holiday 0, Horizon 0, Marlboro 8.8 mg; (b) Merit: in banded paper 0.418 mg; in tobacco 10.23 mg; (c) In hand rolled cigarettes: in the papers < 0.08 mg; in hand rolled tobacco 13.3-15.0 mg; (d) In hand rolling papers of reconstructed cigarettes: < 0.018 mg. 3. Requiring manufactured cigarettes to compulsorily self-extinguish when left unattended was supported by 67% of smokers, 61% of manufactured cigarette smokers, 82% of hand rolled smokers, and by 68% of non-smokers. CONCLUSION: The wrapping paper is a key determinant of whether or not unpuffed cigarettes burn their full length. Using international test methods, popular brands of manufactured cigarettes all burnt full length, but none did so when re-wrapped in hand rolling cigarette paper. This provides a ready-to-hand smoker acceptable standard for reducing ignition potential from manufactured cigarettes, as a basis for regulation or litigation.

Adolescent↗

PubMed1979

Coconut water as a rehydration fluid.

The recent epidemic of cholera on the Pacific Ocean atoll of Tarawa, Gilbert Islands renewed interest in the use of coconut water as a rehydration fluid. Fifty-one samples of coconut water from Tarawa were analysed for a variety of constituents to assess its potential usefulness in the oral and parenteral rehydration of patients with cholera and other severe forms of gastroenteritis. Compared to oral rehydration fluids known to be effective in cholera, coconut water was found to have adequate potassium and glucose content, however was relatively deficient in sodium, chloride and bicarbonate. The addition of table salt to the coconut water is suggested to compensate for the sodium and chloride deficiency. In areas of the world where coconuts are plentiful, the advantages of sterility, availability and acceptability make coconut water theoretically feasible for the oral rehydration of patients with severe gastroenteritis when conventional fluids are unavailable.

Calcium↗

PubMed1978

Nutritional Requirements of Selenomonas ruminantium for Growth on Lactate, Glycerol, or Glucose.

The nutritional requirements of Selenomonas ruminantium HD4 for growth on glucose, glycerol, or lactate were investigated to clarify the results of previous studies and to relate the nutrition of the organism to its physiology. The organism required l-aspartate, CO(2), p-aminobenzoic acid, and biotin for growth on a lactate-salts medium that contained small amounts of dithiothreitol. Aspartate could be replaced by l-malate or fumarate but not by succinate or l-asparagine. Requirements for growth with glycerol as an energy source were similar, except that aspartate was not required. With glucose as the energy source, neither aspartate nor p-aminobenzoic acid was required, but a requirement for volatile fatty acids, which could be met by n-valerate, was observed. CO(2) was required for growth on lactate or glycerol but not on glucose on complex media containing Trypticase and yeast extract. Sulfide could be used as the sole source of sulfur.

Journal Article↗

PubMed1975

H2 production by Selenomonas ruminantium in the absence and presence of methanogenic bacteria.

Selenomonas ruminantium is a nonsporeforming anaerobe that ferments carbohydrates primarily to lactate, propionate, acetate and CO2. H2 production by this species has not been previously reported. We found, however, that some strains produce trace amounts of H2 which can be detected by sensitive gas chromatographic procedures. H2 production is increased markedly, in some cases almost 100-fold, when the selenomonads are co-cultured with methane-producing bacteria. Growth of the methane-producing bacteria depends on H2 production by the selenomonads and the subsequent use of H2 for the reduction of CO2 to CH4. Although no free H2 accumulates in the mixed cultures, the amount of H2 formed by the selenomonads can be calculated from the amount of methane produced. These studies indicate that the conventional methods for measuring H2 production by pure cultures do not provide an adequate estimate of an organism's potential for forming H2 in an anaerobic ecosystem when H2 is rapidly used, e.g., for formation of CH4.

Bacillaceae↗