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Biomedical subjects

F C Jones

Publications and source records attributed to F C Jones.

At least 19 recordsLinked to original sources
PubMed2006

Reproductive isolation in a threespine stickleback hybrid zone.

In many estuarine sites, morphological and genetic differences between anadromous and freshwater threespine sticklebacks are maintained despite breeding in sympatry. Here, we investigate the maintenance of this morphological divergence in a natural hybrid zone in the River Tyne, Scotland. We provide a morphological description of the hybrid zone, and using a Bayesian MCMC approach, identified distinct anadromous and freshwater genetic clusters. Anadromous and freshwater sticklebacks breed in spatial and temporal sympatry in the lower reaches of the River Tyne. The frequency of hybrids within these sites (33%) indicates prezygotic isolation is not complete, and suggests that assortative mating is not strong. However, significant heterozygote deficit and cytonuclear disequilibrium in juveniles collected from sympatric sites confirms that barriers to gene flow exist between the morphs in the wild. In addition, we found no evidence of a directional bias in hybridisation, although hybrids with anadromous mothers were more common because anadromous females outnumbered freshwater females within the hybrid zone. We discuss the potential contribution of temporal, spatial, and sexual prezygotic barriers to the observed reproductive isolation as well as postzygotic selection against hybrid zygotes or fry.

Animals↗
PubMed2001

Focus groups with African American adolescents: enhancing recruitment and retention in intervention studies.

This study explores African American adolescents' perceptions about recruitment and retention strategies for intervention studies. Fifteen African American adolescents, ages 13 and 17 years, participated in this focus group study. Adolescents attended one of three groups which varied by size, gender, and the type of chronic condition: well adolescents (n = 7), adolescents with sickle cell disease (n = 5), and adolescents with diabetes (n = 3). Each group of adolescents participated in two group sessions. Content analyses of the two major categories in the study, recruitment and retention, yielded 10 themes. These themes included adolescents' (1) knowledge about their disease; (2) attitudes and expectations of self-care classes; (3) expectations about the research interventions; (4) instructor characteristics; (5) relationships with the researchers; (6) logistical considerations, such as time, location, and setting of interventions; (7) involvement and choice during the intervention; (8) relationships with other teens; (9) incentives for participation, such as food, fun, and money; and (10) the role of health care providers in recruitment and retention for research studies.

Adolescent↗
PubMed1996

African American children and adolescents exposure to community violence: a pilot study.

Children and adolescents living in communities with frequent episodes of violence are an at-risk population. Chronic exposure to community violence can compromise children and adolescents' health, cognitive functioning, and development. This interdisciplinary pilot study was conducted in an urban community to ascertain a description of children and adolescents' exposure to the type and frequency of violence. Children were found to witness more community violence, while adolescents both witness and experience more community and individual-level violence. Reduction of violence and creation of healthy and safe communities are critical to the well-being and productivity of all residents.

Adolescent↗
PubMed1994

A program to measure new energetic particle nuclear interaction cross sections.

The Transport Collaboration, consisting of researchers from institutions in France, Germany, Italy and the USA, has established a program to make new measurements of nuclear interaction cross sections for heavy projectiles (Z > or = 2) in targets of liquid H2, He and heavier materials. Such cross sections directly affect calculations of galactic and solar cosmic ray transport through matter and are needed for accurate radiation hazard assessment. To date, the collaboration has obtained data using the LBL Bevalac HISS facility with 20 projectiles from 4He to 58Ni in the energy range 393-910 MeV/nucleon. Preliminary results from the analysis of these data are presented here and compared to other measurements and to cross section prediction formulae.

Cosmic Radiation↗
PubMed1988

Antihistamine blockade of alcohol-induced flushing in orientals.

The so-called Oriental flushing reaction associated with ingestion of small amounts of alcohol was antagonized by combined antihistamine administration. In stage one of the study, the flushing reaction to low doses of alcohol was produced in Orientals. Most subjects experienced a cutaneous flush, an increase in skin temperature, a decrease in blood pressure, an increase in pulse rate and subjective symptoms such as dizziness, sleepiness, anxiety, headache, generalized weakness and nausea. Before the administration of alcohol, one-half of the subjects were given 50 mg of diphenhydramine (H1 receptor antagonist) and 300 mg of cimetidine (H2 receptor antagonist). The second half received placebo tablets. The clearest difference between the antihistamine group and placebo group was in the skin flushing reaction. The antihistamine group showed a significant reduction in the skin flush. The antihistamine also neutralized the systolic hypotension induced by the administration of alcohol. The possible importance of histamine in the expression of sensitivity to alcohol is considered. The relevance to genetic susceptibility for development of alcoholism is discussed.

Adolescent↗
PubMed1987

Histamine receptor antagonism of intolerance to alcohol in the Oriental population.

The Oriental flushing reaction is an adverse response to alcohol that appears to be genetically determined. In this study, the Oriental flushing reaction that was produced with ingestion of small amounts of alcohol was antagonized by antihistamine administration. A group of 17 subjects was tested. Each subject received placebo, diphenhydramine 50 mg (H-1 receptor antagonist), and cimetidine 300 mg (H-2 receptor antagonist) singularly and in combination. Alcohol was then administered orally. Most subjects given placebo experienced the typical flushing reaction that included a cutaneous flush, increase in skin temperature, decrease in blood pressure, increase in pulse rate and subjective symptoms such as dizziness, sleepiness, anxiety, headache, generalized weakness, and nausea. The flush, temperature and systolic hypotension were significantly blocked by the combined antihistamine administration. Cimetidine given alone blocked the flush, temperature increase, and systolic hypotension significantly more than diphenhydramine but less than the combined antihistamines. Diphenhydramine was similar to placebo in its effect on the flushing reaction. The role of histamine in the expression of tolerance to alcohol is not known. Antihistamine antagonism of the adverse flushing reaction suggests that histamine receptors may participate in the intolerance to ethanol in Orientals. Histamine may be an important protective factor in the low prevalence of alcoholism in Orientals.

Adolescent↗
PubMed1987

Combined antihistamine antagonism of the flushing reaction to alcohol.

The so-called Oriental flushing reaction associated with ingestion of small amounts of alcohol was antagonized by combined antihistamine administration. In stage one of the study, the flushing reaction to low doses of alcohol was produced in Orientals. Most subjects experienced a cutaneous flush, increase in skin temperature, decrease in blood pressure, increase in pulse rate and subjective symptoms such as dizziness, sleepiness, anxiety, headache, generalized weakness and nausea. One half of the group of subjects was then given diphenhydramine, 50 mg (H1 receptor antagonist) and cimetidine, 300 mg (H2 receptor antagonist) and the second half received placebo tablets before the administration of alcohol. The clearest difference between the antihistamine group and placebo group was in the skin flushing reaction. The antihistamine group showed a statistically significant reduction in the skin flush. The antihistamines also neutralized the systolic hypotension induced by the administration of alcohol.

Adult↗
PubMed1984

Psychological and demographic characteristics of persons reporting out-of-body experiences.

Three hundred, thirty-nine subjects who reported out-of-body experiences were compared to 81 subjects who had a strong interest in such phenomena but had not had the experience. They were also compared with several other groups on a scale of psychological adjustment. No distinctive psychological profile could be delineated, but the OBE subjects were less danger-seeking than the comparison group. Also, they showed significantly better psychological adjustment than a group of psychiatric patients and were roughly equivalent to a group of randomly selected college students. Demographic factors were discussed.

Adult↗
PubMed1982

Differential diagnosis of altered mind/body perception.

Considerable confusion exists in the psychiatric literature concerned with states of consciousness in which there is an altered perception of the mind/body relationship; related but different terms are often used interchangeably, with a lack of definitional rigor. The purpose of this paper is to bring clarity to this group of related phenomena by differentiating out-of-body experience (OBE) from depersonalization, autoscopic phenomena and schizophrenic body distortions (such as boundary loss), which are the principal entities with which the syndrome may be confused. The problem of variable definition of the syndromes is compounded by the fact that some studies deal with psychiatric or medical patients, others focus on nonpatients, and still others deal with both groups. The fact that some groups of persons with experiences of altered mind/body perception do not define themselves as patients, do not seek treatment, and may not need treatment underscores the need for clarification. Following an explication of the different syndromes and their characteristics, we will briefly consider treatment implications.

Adolescent↗
PubMed1982

The out-of-body experience: a phenomenological typology based on questionnaire responses.

The authors review the few surveys that have been made of the incidence of out-of-body experiences. They then present data on 339 respondents to questionnaires who reported having had out-of-body experiences and 81 who had not. They analyze these data according to the conditions existing at the time of the experience, phenomenological features, and the long- and short-term impact of the experience. Finally, they raise questions about the etiology of out-of-body phenomena and their meaning to individuals who have such experiences.

Adolescent↗
PubMed1981

Do "near death experiences" occur only near death?

Near deaths experiences are being reported with increasing frequency, but whether the constellation of factors comprising these experiences is unique to near death situations is unknown. This investigation compared near death experiences to other out-of-body experiences to determine if there are unique features associated with near death experiences. Our results indicate that there are no characteristics which are exclusive to near death situations, but our analysis of t-tests is highly suggestive of a number of distinguishing features which differentiate near death experiences from other out-of-body experiences.

Death↗
PubMed1980

Growth of hebdomadis group of leptospires in solid medium.

Leptospira hardjo, szwajizak, and sejroe produced colonial growth in bovine albumin polysorbate 80 (BAP80) solid medium which had been supplemented either with sodium pyruvate (100 micrograms/ml) or with 5% rabbit serum. Leptospira hardjo produced two morphologic types of colonies in both supplemented media. Growth did not occur with any of the three serovars in the unsupplemented BAP80 medium. These results indicate that addition of either rabbit serum or sodium pyruvate would aid in promoting growth of some fastidious leptospires.

Culture Media↗
PubMed1972

Modification of behavior problems in the home with a parent as observer and experimenter.

Four parents enrolled in a Responsive Teaching class carried out experiments using procedures they had devised for alleviating their children's problem behaviors. The techniques used involved different types of reinforcement, extinction, and punishment. One parent increased the frequency of the wearing of an orthodontic device during five daily time checks by making an immediate monetary payoff contingent on wearing the device. A second parent increased the number of points earned for doing daily household tasks by providing back-ups for which the points could be exchanged. The parents of a 4-yr-old boy decreased the frequency of whines, cries, and complaints by removing social attention when such behavior occurred. A mother decreased the duration of time it took for her 5-yr-old daughter to get dressed by making permission to watch television contingent on dressing within 30 min of the time she got up in the morning. Brief reversals of contingencies were used to show causal relationships between the procedures used and the changes in behavior. Checks on the reliability of measurement were made by persons present in the home.

Journal Article↗
PubMedDate not supplied

Psychoeducational groups to promote effective coping in school-age children living in violent communities.

Children living in violent communities may experience chronic stress, which may place them at risk to develop mental health problems. Children who learn to cope effectively with stress develop protective mechanisms that promote and enhance mental health. The use of psychoeducational groups to promote and enhance effective coping in children who live in communities with chronic violence has not received much attention in the professional literature. This paper discusses the process of conducting community-based psychoeducational groups with two groups of children aged 6 to 8 years and 9 to 12 years in a community "safe house." Strategies to promote and enhance coping in the areas of safety, self-esteem/self-understanding, and power and competence in children are discussed. An informal evaluation and recommendations for the use of psychoeducational groups as a community-based intervention are presented.

Adaptation, Psychological↗