Biomedical subjects

G M Foster

Publications and source records attributed to G M Foster.

At least 19 recordsLinked to original sources

PubMed2003

Investigation of the mechanical performance of young glass-ionomer cement using dynamic mechanical analysis.

Glass-ionomer (or more correctly, glass polyalkenoate) cements have wide applications in dentistry. This paper reports an investigation using dynamic mechanical analysis (DMA) on the setting of typical conventional glass-ionomer cements of varying age. Rectangular section cement samples were stored for four weeks in distilled water at 37 degrees C before being tested. The experimental procedure involved the clamping of the sample in tensile mode and heating through a 37-95 degrees C temperature range in water. A general behavioral trend was followed where all the samples showed increased flexibility with rise in temperature until a "threshold" temperature was reached, whereupon sudden tensile stiffening was observed. The temperature at which the stiffening took place was dependent on the age of the cement, and was interpreted in terms of the secondary cement forming reactions of silica and phosphate. The younger samples stiffened at significantly lower temperatures than the older ones. The activated nature of glass-ionomer setting chemistry meant that younger cements could be prematurely aged through heating. Differential scanning calorimetry was used to study the effect of heating on the distribution of loosely bound water in the cements that had, and had not been exposed to a DMA cycle. Most notably, it was seen that the DMA process did not affect the water in the matrix. This leant further credence to the hypothesis that the stiffening observed during the DMA heating process was caused by accelerated network formation.

Journal Article↗

PubMed2000

Microclimate monitoring of indoor environments using piezoelectric quartz crystal humidity sensors.

The aim of this paper is to describe indoor microclimate monitoring at two different locations, Sandham Memorial Chapel, in Hampshire, England, and the castle El Alcázar, in Segovia, Spain. Piezoelectric quartz crystal sensors with novel humidity sensitive poly(ethyleneimine) coatings and Pt resistance thermometers were used to measure the relative humidity (RH) and temperature gradients across one of the paintings of the British artist, Stanley Spencer, housed in Sandham Memorial Chapel. The measurement period extended from December 1997 to September 1998. Each coated crystal was set in its own housing from which temperature and RH measuring circuits were connected via a cable to the computer. The 9 month monitoring period incorporated the range in seasons from winter through to autumn. Between December and February the RH at the back of the painting was found to be lower than that at the front. In March and April the reverse was true. Additionally, there were large spikes in the data in some of the months for both RH and temperature, probably caused by direct sunlight falling on the sensors. At the second site monitoring was performed for a shorter period, from December 1997 to early January 1998. It served, however, to show that abrupt changes can occur in the microclimate surrounding the painting. These fluctuations can with time lead to alterations to the paint surface and result eventually in cracking and damage to the art work.

Air Pollution, Indoor↗

PubMed1992

Fallen Fontanelle in the American Southwest: a commentary.

Explore the source record for details and available documents.

Humans↗

PubMed1987

Bureaucratic aspects of international health agencies.

In this paper the large international health agencies are viewed as bureaucracies, i.e. in Max Weber's sense as rational administrative organizations. The kinds of activities in which they engage, and the effectiveness of their programs, are interpreted as a function of their structural and dynamic characteristics, and of the professional assumptions held by administrators, planners and technical specialists. International health agency activities are placed in the context of the 'donor-recipient' model that characterizes post-World War II international developmental assistance programs. Some of the strengths and weaknesses of these organizations are noted, and linked to the organizations' structural, dynamic and professional characteristics.

Community Participation↗

PubMed1987

World Health Organization behavioral science research: problems and prospects.

The stated goals of World Health Organization-supported behavioral research are applied: to contribute to planning and policy decision-making, and to improve health care delivery methods. The evidence suggests the organization is getting less for its behavioral research dollar than it ought to: much research has been of poor quality, and researchers often appear more concerned with research design elegance than with practical application of results. Professional and structural factors explain this picture. Physician-dominated research committees that evaluate research applications assume that quantitative hypothesis-testing investigation is the only acceptable research model. Hence, in their grant applications behavioral scientists conform to the expectations of research committees, stressing quantitative methods and slighting the qualitative approaches that often are more productive in providing operational information. Research committee members also often fail to understand the scope of behavioral research possibilities: hoped-for results are limited to information on how to change community behavior more nearly to conform to the needs of health care delivery programs. Research on organization policies and programs is viewed as irrelevant and perhaps even threatening. To improve the quality and utility of WHO-sponsored behavioral research, the author suggests a workshop of organization personnel and short-term consultants and temporary advisors with prior experience, to evaluate past research, to identify its strengths and weaknesses, and to recommend modified research support procedures to produce higher quality, operationally-useful results.

Behavioral Sciences↗

PubMed1985

How to get well in Tzintzuntzan.

Latin American humoral pathology, the so-called 'hot-cold syndrome' has been extensively described during the past 50 years. Most attention has been directed to the characteristics of the 'hot-cold' classification, the basis for ascription of humoral quality, the degree of individual variation in assigning qualities and above all, to etiology. Almost no systematic attention has been given to humoral therapies. This paper describes and classifies the wide variety of therapies characterizing the traditional humoral medicine of Tzintzuntzan, Michoacán, Mexico. The names of these therapies, and those of the illnesses for which they are prescribed, point directly to Spanish and Mexican medical texts and home-care recetarios of the colonial period, publications reflecting classical Graeco-Roman medicine. The presence of significant numbers of Spaniards and Spanish-speaking residents in Tzintzuntzan for three centuries following the Conquest provides an explanation as to how classical humoral pathology could become rooted in a Mexican village.

Attitude to Health↗

PubMed1985

Food safety and the behavioural sciences.

International health programmes have been a major stimulus to the development of several specialties collectively known as medical behavioural science. Each new programme of the international and national agencies has led to an expansion of the areas of behavioural scientists in health research. This may also be expected from WHO's Food Safety Programme; its activities, and the findings contained in the report of a recently held meeting of a Joint FAO/WHO Expert Committee on Food Safety, are bringing to light the need for, and the opportunities in, behavioural science research on food safety. Although significant behavioural research has been done in nutrition and the treatment of diarrhoeal diseases, almost no attention has been paid to the ways in which food is rendered unsafe for human consumption or to the ways in which food safety can be increased. Suggestions are made as to the kinds of research needed, the data that must be gathered, and the ways in which, especially through health education, this information can be made operational.

Accident Prevention↗

PubMed1984

How to stay well in Tzintzuntzan.

In this paper the basic principles of humoral pathology in Tzintzuntzan, Michoacán, Mexico are outlined, and related to the strategies people follow to avoid illness. It is suggested that most Latin American accounts of humoral pathology are deficient in their failure to give due weight to thermal temperature, as well as to the metaphoric qualities embodied in the 'hot-cold dichotomy'. Emphasizing preventive rather than therapeutic measures highlights a basic, usually overlooked, characteristic of humoral pathology: whereas the well-known 'principle of opposites' explains therapies, a diametrically-opposed 'principle of the avoidance of opposites' explains most behavior when people are well. Although scientific medicine is now first choice for villagers for therapy, explanation of illness continues to be based on humoral principles. Since people believe humoral principles account for what has happened to them, and since they believe that humoral precepts in prevention give them a high degree of control over their health, it is likely that humoral pathology--at least as a belief system--will flourish for a long time to come.

Attitude to Health↗

PubMed1984

Anthropological research perspectives on health problems in developing countries.

Anthropological research on health problems in developing countries during the past 30 years, and present/future research on the same topic, are considered in the light of (a) the changing health picture in developing countries and (b) the major health enterprises of developing countries and participating multilateral and bilateral agencies. The author suggests that modern medicine in recent years has become the first choice of most traditional peoples most of the time. It is because the supply of modern health care cannot keep up with the demand that the Primary Health Care (PHC) movement has arisen. With respect to the use of traditional curers in PHC it is pointed out that (a) they are not replacing themselves, (b) many have become ' neotraditional curers ' making extensive use of modern drugs and (c) spiritualist curing is replacing much traditional medicine. The question is, then, when we advocate the use of 'traditional curers ' in PHC programs, what exactly are we proposing? All of the above? Some of the above? Traditional healers only, strictly defined? The author also suggests that some early anthropological stereotypes of health behavior need revision, particularly those having to do with effective doctor-patient interaction. Finally, if anthropologists are effectively to explore the sociocultural aspects of health and illness, they must study health care delivery systems as intensively as community/patient behavior.

Anthropology↗

PubMed1984