Search PubMed⌕ Search

Biomedical subjects

V C Kennedy

Publications and source records attributed to V C Kennedy.

At least 19 recordsLinked to original sources
PubMed2001

Interparticle migration of metal cations in stream sediments as a factor in toxics transport.

Sorption of metal cations by stream sediments is an important process affecting the movement of released contaminants in the environment. The ability of cations to desorb from one sediment particle and subsequently sorb to another can greatly affect metal transport rates but rates for this process have not been reported. The objective of this study was to determine the rate at which sorbed metals can migrate from contaminated sediment particles to uncontaminated sediment particles as a function of the concentration of the contaminating solution and the duration of the contact with the contaminating solution. Samples of small sediment particles were exposed to solutions containing cobalt, after which they were rinsed and combined with larger uncontaminated sediment particles in the presence of stream water. Initial concentrations of the contaminating solution ranged from 1ng/l to 1000mg/l and exposures to the contaminating solution ranged from 6h to 14 days. The rate of the migration increased with increasing concentrations in the contaminating solution and with decreasing times of exposure to the contaminating solution. Under the conditions of these experiments, the time required for the migration to reach equilibrium was on the order of months or longer. In separate experiments, the kinetics of adsorption and desorption of cobalt were measured as a function of concentration of the contaminating solution. The time required to reach adsorption equilibrium increased with increasing concentration in the contaminating solution. Times to sorption equilibrium were on the order of months. Desorption was much slower than adsorption and, together with intraparticle diffusion, probably controls the rate of migration from contaminated to uncontaminated sediment. The results of this study show that interparticle migration of metal cations can proceed at significant rates that are strongly influenced by the length of time that the metal has been in contact with the sediment.

Adsorption↗
PubMed2001

A systems approach to public health workforce development.

During the 1990s, several distinct but interrelated efforts to strengthen the public health infrastructure were launched. Defining public health work in terms of core functions and essential services, these efforts focused on the competence of the workforce and the performance of public health agencies. The systems approach offered here highlights the relationships and interdependencies among these three components of public health practice: (1) the work, (2) the worker, and (3) the work setting. The model suggests that advances in public health workforce development may require major public health organizational development efforts.

Competency-Based Education↗
PubMed1999

Public health workforce information: a state-level study.

A two-stage sample survey was used to estimate the size of Texas' professional public health workforce and to describe its composition in terms of employment settings, job characteristics, and individual characteristics. The estimated 17,700 public health professionals employed in 1995 represented approximately three percent of the state's total health workforce. About 55 percent of all these professionals worked in agencies that provide population-based public health services. An estimated seven percent had formal public health education. These findings raise issues concerning the numerical adequacy of the state's supply of public health professionals, the adequacy of their educational preparation, and the human resources capacity of the state's official public health agencies.

Adult↗
PubMed1994

Supply and distribution of primary care physicians and medical school enrollments in Texas.

The search for policy options to contain health-care costs has sparked renewed national interest in reducing medical school enrollments. Concurrently, the goals of improving the specialty and geographic distribution of physicians have proved elusive both at the state and national levels. This study reexamines and reaffirms the conclusions of an earlier study that suggested enrollment reductions in Texas might decrease rather than increase the supply of primary care and rural physicians.

Education, Medical↗
PubMed1990

The validity of single-item, self-assessment questions as measures of adult physical activity.

Individual energy expenditure (kcal/kg/day) was calculated from a detailed set of questions from the Health Promotion and Disease Prevention Supplement of the 1985 National Health Interview Survey. Responses to three single-item, self-assessment questions were compared to the energy expenditure variable to test criterion validity. Spearman's correlation coefficient revealed moderate correlations between energy expenditure and corresponding levels of self-assessed leisure-time physical activity for each single-item question (r = 0.14 to 0.41). For purposes of measuring prevalence of physical activity, the energy expenditure variable was used to categorize individuals into activity levels. The single-item questions were found to have Spearman's correlations with the categorical measures ranging from 0.11 to 0.37 for leisure-time activities. Generally higher correlations were found for males and younger age groups (18-34 years). The relationships were interpreted as being weak relative to an expected correlation of 0.75 for criterion validation. However, the single-item questions show promise for obtaining proxy estimates of the degree of leisure-time physical activity in a population.

Adult↗
PubMed1987

Estimating the impact of state manpower policy: a case study of reducing medical school enrollments.

Perceptions of an impending oversupply of physicians have prompted proposals to reduce medical school enrollments in a number of states. Most of these states are also concerned with improving the specialty and geographic distribution of their medical manpower. The present study provides estimates of the effects of reduced numbers of in-state medical school graduates upon the future supply of physicians in Texas, and examines the medical school origin, medical specialty, and practice location of selected groups of Texas physicians. The results suggest that in Texas enrollment reductions would have no significant impact on physician supply over the next 15 years, and might actually prove counterproductive in altering physician distribution. The analysis of Texas data illuminates the unintended consequences likely to accompany a policy option that has been widely embraced by state officials largely on the basis of its intuitive appeal.

Forecasting↗
PubMed1986

Influencing physician distribution in the South: lessons from a study in Texas.

Analysis of recent and projected trends in the geographic distribution of Texas physicians indicates that maldistribution may continue to be a problem into the foreseeable future. A survey of manpower officials in other southern states and a review of research on the effectiveness of various policy interventions reveals that programs involving preferential medical school admissions and Medicaid reimbursement levels may hold the most promise for Texas and other southern states seeking to alleviate physician maldistribution.

Delivery of Health Care↗
PubMed1985

Patient characteristics and the demand for care in two freestanding emergency centers.

Because freestanding emergency centers (FECs) represent a new approach to the delivery of health care services, little is known about them and their patient populations. This article reports on a study of 551 systematically sampled users of two commonly owned FECs. It describes the patient population and develops an economic demand model to compare the patients' use of the FECs with their use of other sources of ambulatory care. The typical FEC patient is a 27-year-old white male with at least a high school education. Age, education, and affiliation with a regular source of care most influenced FEC use, whereas health status and affiliation with a regular source best predicted the use of other sources of ambulatory care.

Adult↗
PubMed1985

Determining the costs of self-study for accreditation: a method and a rationale.

Current economic conditions have produced a resurgence of concern among health professions educational institutions about the costs of accreditation. Cost issues cannot be satisfactorily addressed until appropriate methods of cost determination are established and widely applied. This report describes a methodology which was successfully applied in one school and may serve as a model for other institutions and programs.

Accreditation↗
PubMed1980

Exposure to a rural population in a rural residency training program.

Previous reports of rural training programs conducted by medical schools have not examined the relationship between the population residing in an area and the population receiving medical services through the clinical training program. In the present study rural household survey data were compared with patient encounter data from a rural ambulatory cliinic engaged in training Family Practice residents from the Texas Tech University School of Medicine. Clinic patients were found to resemble the rural population subgroup that visits a physician at least once a year. Wide variations in individual clinical experiences were observed when health problems and conditions encountered by residents were compared with problems encountered in the clinic as a whole. In light of current national efforts to increase medical care access in unserved and underserved populations, the demographic findings raise questions concerning appropriate patient exposure goals in clinical training programs.

Adolescent↗
PubMed1980

Locational aspects of medical care-seeking in a rural population, with some implications for public policy research.

The published literature suggests that two factors affect where people seek medical care: the characteristics of the population and the organization of the health care delivery system. In this study, survey data from a rural west Texas population were used to evaluate the relative importance of these factors in determining whether individuals are affiliated with an urban or rural source of care. Population characteristics appear to be the more important determinants; in fact, where people seek care may not be substantially altered by restructuring the organizational and geographic components of the health care delivery system.

Adolescent↗
PubMed1979

Rural access to regular source of medical care.

Household survey data from an adult rural west Texas population were used to investigate the role of demographic, economic, attitudinal, and need-related factors in (a) explaining physician contact and volume of physician visits and (b) differentiating between those individuals who have and those who do not have a regular source of medical care. Fifty-two percent of the variance in visit volume were explained; compared with the findings reported in similar studies, alignment with a regular source of care was more closely associated with visit volume and physician contact. Although the variance explained in having a regular source was only about 18%, the findings suggest that factors determining alignment with a regular source may differ considerably from those determining other dimensions of utilization. Furthermore, patterns evident across several dimensions in rural populations may be quite different from those exhibited in other populations.

Adult↗
PubMed1976

Interpreting legislative voting patterns on health issues: a method and rationale.

Crucial decisions affecting the health field are increasingly being made in the political arena. To interpret and effectively influence these political events, the health specialist must become acquainted with the political decision maker's perspective on health issues. This report presents a method for analyzing legislative voting patterns to determine the issue structure within which health-related legislative decisions are made. Once this issue structure has been determined for a given legislative body, relevant strategies for influencing the decision-making process can be designed.

Decision Making↗