234 research outputs found
Distinguishing cancerous from non-cancerous cells through analysis of electrical noise
Since 1984, electric cell-substrate impedance sensing (ECIS) has been used to
monitor cell behavior in tissue culture and has proven sensitive to cell
morphological changes and cell motility. We have taken ECIS measurements on
several cultures of non-cancerous (HOSE) and cancerous (SKOV) human ovarian
surface epithelial cells. By analyzing the noise in real and imaginary
electrical impedance, we demonstrate that it is possible to distinguish the two
cell types purely from signatures of their electrical noise. Our measures
include power-spectral exponents, Hurst and detrended fluctuation analysis, and
estimates of correlation time; principal-component analysis combines all the
measures. The noise from both cancerous and non-cancerous cultures shows
correlations on many time scales, but these correlations are stronger for the
non-cancerous cells.Comment: 8 pages, 4 figures; submitted to PR
Employment, Unemployment and the Health of Pregnant Women
Much of what little we know about the impact of unemployment or health is based upon data or studies of predominantly unemployed men. These studies, though weak in methodology, imply that unemployment may lead to excess morbidity and mortality. This paper reports a study of 4,000 pregnant women in Brisbane. Unemployment amongst women is associated with high-risk health behaviour, which in turn may lead to low birthweight births. Further, unemployed women are more anxious and depressed than are employed women. The mental health of the mother appears to be more closely related to the employment status of her spouse than to her own employment status
The Population Structure of Ten Newfoundland Outports
This is the published version. Copyright 2000 Wayne State University Press.Island populations are most informative in the study of the genetic structure of human aggregates. These populations are often of small size, thus violating the Hardy-Weinberg assumption of infinite size.
Some geographically isolated island populations are further subdivided by religion, ethnicity, and socioeconomic factors, reducing their effective sizes and facilitating genetic changes due to stochastic processes. Because of extreme geographic and social isolation, fishing communities or outports of Newfoundland have been investigated for genetic micro-differentiation through the founder effect and genetic drift (Crawford et al. 1995). The purpose of this paper is to examine the population structure of 10 Newfoundland outports using the allelic frequencies derived from 12 red cell antigens. To achieve this goal, first we calculated gene frequencies using maximum-likelihood estimation procedures. Second, we used /{-matrix methods to explore population differentiation. Third, we regressed mean per-locus heterozygosity on genetic distance from the gene frequency centroid to identify the most isolated populations. On the basis of this information, the three outports of Seal Cove, Island Harbor, and Tilting were found to be genetically differentiated from the other small populations. Moreover, religious and geographic subdivisions appear to explain the observed genetic variation
Socio-Economic Status and Pregnancy Outcome: An Australian Study
A prospective cohort of 8556 pregnant women attending the Mater Misericordiae Mothers' Hospital in Brisbane was examined to consider the impact of socio-economic status on pregnancy outcome. The indicators of socio-economic status selected were family income, maternal education and paternal occupational status. Pregnancy outcomes considered were preterm delivery, low birthweight, low birthweight for gestational age, and perinatal death. Subsidiary analyses were also undertaken for Apgar scores, time to establish respiration, need for mechanical respiration and admission to intensive care. Before adjustment, the main consistent association was between the occupational status of the father and three measures of perinatal morbidity. Initial adjustment for the mother's socio-demographic background and weight/height ratio reduced the strength and statistical significance of the above associations, while further adjustment for lifestyle variations between the three status groups further reduced the above associations to marginal statistical significance. The findings suggest that observed class differences in pregnancy outcome are attributable to the mother's personal characteristics (height/weight, parity) and her lifestyle
Maternal Depression, Paternal Psychopathology, and Adolescent Diagnostic Outcomes
The authors examined the relationship between maternal depression, paternal psychopathology, and adolescent diagnostic outcomes in a community sample of 522 Australian families. They also examined whether chronic family stress, father's expressed emotion, and parents' marital satisfaction mediated the relationship between parental psychopathology and adolescent outcomes. Mother's education, child's gender, and family income were covaried in all analyses. Results revealed that maternal depression and paternal depression had an additive effect on youth externalizing disorders. In addition, maternal depression interacted with both paternal depression and paternal substance abuse in predicting youth depression but not youth nondepressive disorders. Chronic family stress and father's expressed emotion appeared to mediate the relationship between parental psychopathology and youth depression
Intergenerational Transmission of Depression: Test of an Interpersonal Stress Model in a Community Sample
An interpersonal stress model of depression transmission was tested in a community sample of nearly 800 depressed and never-depressed women and their 15-year-old children. It was hypothesized that maternal depression (and depression in the maternal grandmother) contributed to chronic interpersonal stress in the mothers, affecting quality of parenting and youths' social competence. In turn, poor social functioning and interpersonal life events caused at least in part by the youths were predicted to be the proximal predictors of current depressive symptoms and diagnoses. Structural equation modeling confirmed the predicted associations among variables and the link between youth chronic and episodic interpersonal stress and depression. Additionally, the association between maternal and child depression was entirely mediated by the predicted family and interpersonal stress effects
Information ontrol and the exercise of power in the obstetrical encounter
Interactions between doctor and patient involve participants with unequal power and possibly different interests. While a number of studies have focused upon the doctor/patient relationship, few have examined the utility of the concept of power and its capacity to help us understand the outcome of these interactions. The information sought by pregnant women from their obstetricians is used to provide a case study of one conceptualization and test of the utility of the concept of power. Pregnant women and their obstetricians are found to have different perceptions of the information that should be exchanged during their interactions. Women generally fail to obtain the information they want. Lower social class patients desire more and obtain less information than their higher status counterparts
Multiresolution analysis of active region magnetic structure and its correlation with the Mt. Wilson classification and flaring activity
Two different multi-resolution analyses are used to decompose the structure
of active region magnetic flux into concentrations of different size scales.
Lines separating these opposite polarity regions of flux at each size scale are
found. These lines are used as a mask on a map of the magnetic field gradient
to sample the local gradient between opposite polarity regions of given scale
sizes. It is shown that the maximum, average and standard deviation of the
magnetic flux gradient for alpha, beta, beta-gamma and beta-gamma-delta active
regions increase in the order listed, and that the order is maintained over all
length-scales. This study demonstrates that, on average, the Mt. Wilson
classification encodes the notion of activity over all length-scales in the
active region, and not just those length-scales at which the strongest flux
gradients are found. Further, it is also shown that the average gradients in
the field, and the average length-scale at which they occur, also increase in
the same order. Finally, there are significant differences in the gradient
distribution, between flaring and non-flaring active regions, which are
maintained over all length-scales. It is also shown that the average gradient
content of active regions that have large flares (GOES class 'M' and above) is
larger than that for active regions containing flares of all flare sizes; this
difference is also maintained at all length-scales.Comment: Accepted for publication in Solar Physic
Tracking science : an alternative for those excluded by citizen science
Abstract: In response to recent discussion about terminology, we propose “tracking science” as a term that is more inclusive than citizen science. Our suggestion is set against a postcolonial political background and large-scale migrations, in which “citizen” is becoming an increasingly contentious term. As a diverse group of authors from several continents, our priority is to deliberate a term that is all-inclusive, so that it could be adopted by everyone who participates in science or contributes to scientific knowledge, regardless of socio-cultural background. For example, current citizen science terms used for Indigenous knowledge imply that such practitioners belong to a sub-group that is other, and therefore marginalized. Our definition for “tracking science” does not exclude Indigenous peoples and their knowledge contributions and may provide a space for those who currently participate in citizen science, but want to contribute, explore, and/or operate beyond..
Depressed Adolescents of Depressed and Nondepressed Mothers: Tests of an Interpersonal Impairment Hypothesis
Two groups of depressed youngsters were compared. From an interpersonal perspective, it was hypothesized that depressed adolescents of depressed mothers would have significantly more interpersonal dysfunction than depressed youngsters of nondepressed mothers. In a large community sample of youth and their families, 65 depressed offspring of women with histories of a major depressive episode or dysthymia were compared with 45 depressed offspring of never-depressed women. As predicted, after controlling for current symptoms and family social status variables, depressed offspring of depressed mothers displayed significantly more negative interpersonal behaviors and cognitions compared with depressed offspring of nondepressed mothers, but they did not differ on academic performance. Implications concerning mechanisms, course, and consequences of different forms of adolescent depression are presented
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