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PubMed1998

Adolescent abortion and parental notification: evidence for the importance of family functioning on the perceived quality of parental involvement in U.S. families.

This study was an investigation of the relationship between family variables and the perceived quality of parental involvement following parental notification of an adolescent's decision to have an abortion. Demographics, family religiosity, and family functioning variables were examined. Pregnant adolescent clients from seven abortion clinics in three states completed a survey assessing their perception of the quality of parental involvement and the family variables. Only family functioning variables were significantly related to the perceived quality of parental involvement. Family adaptability (the family's ability to change its power structure, role relationships, and relationship rules in response to situational and developmental stress) was the most predictive. Adolescents from adaptable families had a more positive experience with parental involvement than adolescents from less adaptable families.

Abortion, Legal↗
PubMed1975

White noise analysis of Phycomyces light growth response system. II. Extended intensity ranges.

By means of white gaussian noise stimulation, the Wiener kernels are derived for the Phycomyces light growth response for a variety of intensity conditions. In one experiment the intensity I, rather than log I, is used as the input variable. Under the very limited dynamic range of that experiment, the response is fairly linear. To examine the dependence of the kernels on dynamic range, a series of experiments were performed in which the range of log I was halved and doubled relative to normal. The amplitude of the kernels, but not the time course, is affected strongly by the choice of dynamic range, and the dependence reveals large-scale nonlinearities not evident in the kernels themselves. In addition kernels are evaluated for experiments at a number of absolute intensity levels ranging from 10(-12) to 10(-3) W/cm2. The kernel amplitudes are maximal at about 10(-6) W/cm2. At 10(-12) W/cm2, just above the absolute threshold, the respond is very small. The falloff at high intensity, attributable to inactivation of the photoreceptor, is analyzed in the framework of a first-order pigment kinetics model, yielding estimates for the partial extinction coefficient for inactivation epsilonI455 = (1.5 +/- 0.2) X 10(4) liter/mol-cm and a regeneration time constant of tau = (2.7 +/- 0.6) min. A model is introduced which associates the processes of adaptation and photoreceptor inactivation. The model predicts that the time constants for adaptation and pigment should be identical. This prediction is consistent with values in this and the preceding paper. The effects of pigment inactivation are simulated by a linear electronic analog circuit element, which may be cascaded with the linear simulator circuit in the preceding paper.

Adaptation, Physiological↗
PubMed2006

A prototype approach to personality disorder diagnosis.

OBJECTIVE: Virtually no research has tested alternatives to the diagnostic method used since DSM-III, which requires decisions about the presence/absence of individual diagnostic criteria, followed by counting symptoms and applying cutoffs (the count/cutoff method). This study tested an alternative, prototype matching procedure designed to simplify diagnosis. The procedure was applied to personality disorders. METHOD: A random national sample of psychiatrists and clinical psychologists (N=291) described a randomly selected patient in their care. Clinician-provided diagnostic data were used to generate categorical and dimensional DSM-IV diagnoses (number of symptoms present per disorder). Clinicians also used one of two prototype matching systems to provide a diagnosis for the selected patient. RESULTS: Prototype diagnosis led to reduced comorbidity relative to DSM-IV diagnosis, yielded similar estimates of validity in predicting criterion variables (adaptive functioning, treatment response, and etiology), and outperformed DSM-IV diagnosis in ratings of clinical utility and ease of use. Adding a personality health prototype further increased prediction. CONCLUSIONS: A simple prototype matching procedure provides a viable alternative for improving diagnosis of personality disorders in clinical practice. Prototype diagnosis has multiple advantages, including ease of use, minimization of artifactual comorbidity, compatibility with naturally occurring cognitive processes, and ready translation into both categorical and dimensional diagnosis.

Adaptation, Psychological↗
PubMed2005

Temporal adaptability and the inverse relationship to sensitivity: a parameter identification model.

Following a prolonged period of visual adaptation to a temporally modulated sinusoidal luminance pattern, the threshold contrast of a similar visual pattern is elevated. The adaptive elevation in threshold contrast is selective for spatial frequency, may saturate at low adaptor contrast, and increases as a function of the spatio-temporal frequency of the adapting signal. A model for signal extraction that is capable of explaining these threshold contrast effects of adaptation is proposed. Contrast adaptation in the model is explained by the identification of the parameters of an environmental model: the autocorrelation function of the visualized signal. The proposed model predicts that the adaptability of threshold contrast is governed by unpredicted signal variations present in the visual signal, and thus represents an internal adjustment by the visual system that takes into account these unpredicted signal variations given the additional possibility for signal corruption by additive noise.

Adaptation, Ocular↗
PubMedDate not supplied

Family influences on adaptive development in young children with Down syndrome.

In this study we investigated the extent to which the family environment predicted differences in trajectories of adaptive development in young children with Down syndrome. The sample was comprised of 54 children with Down syndrome and their families who were studied from infancy through the age of 5 years as part of a longitudinal study of children with disabilities. Hierarchical linear modeling (HLM) was used to estimate the parameters of hierarchical growth models in domains of adaptive development. Results indicated that growth in communication, daily living skills, and socialization domains were predicted by measures of the family environment (i.e., family cohesion and mother-child interaction) above and beyond that predicted by maternal education. Further, Bayley MDI measures during infancy did not predict changes in adaptive development in any of the domains. The results are discussed in terms of implications for service provision and for expanding theoretical frameworks to include the development of children with disabilities.

Adaptation, Psychological↗
PubMed1995

Long latency postural reflexes are under supraspinal dopaminergic control.

Scaling of posturally stabilizing long latency (LL) reflexes in tibialis anterior muscles induced by "toe-up" rotational perturbations is abnormal in standing patients with Parkinson's disease. To investigate the contribution of dopaminergic pathways to abnormal scaling, we studied LL reflexes in 22 patients with selective hypodopaminergic syndromes: 10 psychiatric patients taking chronic neuroleptic medication (7 with mild parkinsonism), 8 patients with young-onset Parkinson's disease, and 4 patients with MPTP-induced parkinsonism. Results were compared with those of 10 healthy controls. Stimuli consisted of (a) 10 serial (predictable) perturbations of 4 degrees amplitude, (b) 10 serial (predictable) perturbations of 10 degrees amplitude, and (c) 20 randomly mixed (unpredictable) perturbations of either 4 or 10 degrees amplitude. In normal subjects, LL reflex amplitudes were adapted to match predictable variations in stimulus size, whereas under unpredictable conditions a "default" response emerged that anticipated the 10 degrees perturbation. LL reflex scaling under predictable conditions was intact in patients with neuroleptic-induced parkinsonism and young-onset Parkinson's disease, but the large default LL response under unpredictable conditions was absent. In patients with MPTP-induced parkinsonism, LL reflex scaling was absent during both predictable and unpredictable conditions. We conclude that abnormal scaling of posturally stabilizing LL reflexes is related to decreased supraspinal dopaminergic influence.

1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine↗
PubMed2001

Increased visual after-effects following pattern adaptation in migraine: a lack of intracortical excitation?

Much research on visual function in migraine has examined early aspects of visual processing, often using detection or discrimination measures and stimuli reported to trigger an attack, e.g. striped patterns or flickering lights. Differences between people with and without migraine have been attributed to abnormal cortical processing in migraine, variously described by interictal hyperexcitability, heightened responsiveness, a lack of habituation and/or a lack of intra-cortical inhibition. Here, two experiments are presented that explore a uniquely cortical phenomenon, pattern or contrast adaptation, one using the motion after-effect, one the tilt after-effect. Pattern adaptation reflects specific interactions between groups of neurones and is therefore ideally suited to address proposed models of cortical function in migraine. These models lead to specific predictions in an adaptation study: there should be smaller effects in people with migraine than in people without. The results from both adaptation experiments, however, revealed larger effects in migraine sufferers than in headache-free control subjects. There were no differences between migraine subgroups classified according to the presence or absence of aura. These results are discussed in terms of models of cortical function in migraine.

Adaptation, Psychological↗
PubMed2006

Expressed emotion, adaptation, and patient survival among couples coping with chronic heart failure.

Previous research (J. C. Coyne et al., 2001) that showed that marital functioning predicted mortality among patients with chronic heart failure (CHF) led to an examination of whether expressed emotion (EE) captured negative marital influences on patient survival. The authors assessed EE using 5-min speech samples obtained from patients (137 men and 47 women) and their spouses. Prevalence of EE was low, and patient and spouse EE were unrelated. Spouse EE was not associated with survival, after the authors controlled for severity of illness. Among patient EE variables, high EE status predicted survival, but in the opposite direction of what was anticipated. Overall, relations between EE and self-report measures of adaptation were weak and inconsistent. Despite the strength of findings concerning EE and psychiatric outcomes, EE does not show promise in predicting adaptation to CHF, and researchers and clinicians should instead seek to identify positive marital factors that may promote patient survival.

Adaptation, Psychological↗
PubMed1993

Effects of parental adjustment on the adaptation of children with congenital or acquired limb deficiencies.

Maternal and paternal depression, anxiety, and marital discord were investigated as predictors of depression, anxiety, and self-esteem in 54 children with congenital or acquired limb deficiencies. Higher paternal depression predicted higher child depression and higher anxiety. Higher paternal anxiety predicted higher child depression and anxiety and lower self-esteem. Higher marital discord predicted higher child depression and anxiety and lower self-esteem. Maternal depression and anxiety did not predict child psychological adaptation. Family support had a positive effect on child adaptation, as did parent, classmate, teacher, and friend social support. The findings are discussed in terms of the risk and protective effects of parental distress, marital discord, and social support on the psychological adaptation of children with visible chronic physical disorders. J Dev Behav Pediatr 14:13-20, 1993. Index terms: limb deficiencies, children, adjustment, social support, parental distress, family functioning, marital discord.

Adaptation, Psychological↗
PubMed1994

Donor and recipient predicted lung volume and lung size after heart-lung transplantation.

Lung volumes after heart-lung transplantation (HLT) were recorded and compared with measurements at the time of assessment for surgery and the predicted values for recipients. The influence of donor lung size and recipients' underlying lung disease was evaluated. All patients underwent HLT between April 1984 and April 1991, and only those 82 who survived for at least 6 mo were studied. Mean total lung capacity (TLC) at preoperative assessment was 112% (SD = 28%) of the value predicted for recipients. One month after HLT, mean TLC was 83% (SD = 15%) of the predicted value but increased to 100% (SD = 15%) after 9 mo. No further change in average TLC occurred for 5 yr subsequently. The mean TLC of patients with emphysema before surgery was 164% (SD = 26%) of the predicted value and fell to the predicted value within 1 mo of HLT. The TLC in patients with primary pulmonary hypertension before surgery was close to the predicted value, but postoperative predicted TLC was achieved later than in emphysema patients. A donor-versus-recipient difference in TLC of more than 1L at the time of assessment did not influence the adaptation to the predicted value. FEV1 and vital capacity (VC) rose from means of 70% (SD = 25%) and 63% (SD = 20%) at 1 mo to 96% (SD = 27%) and 91% (SD = 18%), respectively, at 9 mo after HLT. After HLT, TLC returns to the predicted value for the recipient, and not to the preoperative TLC.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1990

The functional significance of auditory adaptation.

If a short duration pulse is added periodically every 30 s to a continuous tone, then the loudness of the continuous tone, which would otherwise remain unchanged, appears to undergo a progressive decline over a period of 3 min. The question at issue is whether the loss of loudness is actually induced by the pulse or merely made obvious. In support of the latter proposition a model has been developed which indicates how the loudness difference between the pulsed and continuous tone will increase as a result of adaptation. However, the model also predicts that a loudness loss should, in addition, be apparent in the pulsed tone itself. This has been confirmed by balancing the loudness in one ear of a 10 dB increment to a continuous tone of 60 dB at 1 kHz with an intermittent pulsed tone of the same frequency in the other. The magnitude of the loudness loss (of the order of 5 dB) accords well with the model prediction. The functional implications are that adaptation of continuous background noise should serve to reduce its masking effect upon speech and other transitory auditory stimuli rendering them more easily detectable.

Adaptation, Physiological↗
PubMedDate not supplied

[Establishing a psychophysiological criterion for the prognosis of the efficiency of the adaptation process].

This paper presents a criterion for measuring the efficiency of adaptation to an altered environment. The criterion is related to the quantitative evaluation of memory adequacy at early stages of the exposure to a new environment. An improvement in the reproduction of emotional words and a slight deterioration of the recollection of neutral words may be regarded as a prognostically significant criterion of the adaptation success. The lack of an improvement in the reproduction of emotionally important information and a significant deterioration of the recollection of neutral information at early stages of adaptation is an adverse sign predicting a potential failure of the adaptation process.

Adaptation, Physiological↗
PubMed2006

Biomarkers in environmental and human health risk assessment.

Marine pollution is a major threat to human and environmental health. Given the complexity of function of marine and coastal ecosystems, it is unlikely that a balanced view of the nature and extent of risk will easily be achieved if human and environmental risk assessments continue to be conducted in isolation. Here, the integration of assessment protocols is advocated as a holistic means of improving risk management. Biomarkers can provide the common conceptual framework and measurable endpoints necessary for successful integration. Examples are given of the ways in which suites of biomarkers encompassing molecular change, cellular pathology and physiological impairment can be developed and adapted for human and ecological scenarios. By placing a greater emphasis on the health status of impacted biota, it is more likely that risk assessment will develop the efficiency, reliability and predictive power to adapt to the unforeseen environmental threats that are an inevitable consequence of human development and global change.

Acetylcholinesterase↗
PubMed2005

The effect of disease life history on the evolutionary emergence of novel pathogens.

We present a general analytical result for the probability that a newly introduced pathogen will evolve adaptations that allow it to maintain itself within any novel host population, as a function of disease life-history parameters. We demonstrate that this probability of "evolutionary emergence" depends on two key properties of the disease life history: (i) the basic reproduction number and (ii) the expected duration of an infection. These parameters encapsulate all of the relevant information and can be combined in a very simple expression, with estimates for the rates of adaptive mutation, to predict the probability of emergence for any novel pathogen. In general, diseases that initially have a large reproductive number and/or that cause relatively long infections are the most prone to evolutionary adaptation.

Adaptation, Physiological↗
PubMed2005

Introduction: food crops in a changing climate.

Changes in both the mean and the variability of climate, whether naturally forced, or due to human activities, pose a threat to crop production globally. This paper summarizes discussions of this issue at a meeting of the Royal Society in April 2005. Recent advances in understanding the sensitivity of crops to weather, climate and the levels of particular gases in the atmosphere indicate that the impact of these factors on crop yields and quality may be more severe than previously thought. There is increasing information on the importance to crop yields of extremes of temperature and rainfall at key stages of crop development. Agriculture will itself impact on the climate system and a greater understanding of these feedbacks is needed. Complex models are required to perform simulations of climate variability and change, together with predictions of how crops will respond to different climate variables. Variability of climate, such as that associated with El Niño events, has large impacts on crop production. If skilful predictions of the probability of such events occurring can be made a season or more in advance, then agricultural and other societal responses can be made. The development of strategies to adapt to variations in the current climate may also build resilience to changes in future climate. Africa will be the part of the world that is most vulnerable to climate variability and change, but knowledge of how to use climate information and the regional impacts of climate variability and change in Africa is rudimentary. In order to develop appropriate adaptation strategies globally, predictions about changes in the quantity and quality of food crops need to be considered in the context of the entire food chain from production to distribution, access and utilization. Recommendations for future research priorities are given.

Climate↗
PubMed1989

A longitudinal analysis of psychological adaptation among survivors of cancer.

This longitudinal study examined the psychological adaptation of newly diagnosed cancer patients. Findings showed a decline in patient's mental health status over time. Initial psychological status and other psychosocial factors, and not illness-related factors, were predictive of subsequent adaptation. Two psychologically vulnerable patient groups were identified: those who remained distressed over time and those whose mental health status declined over time.

Adaptation, Psychological↗
PubMed2005

Continuous energy variation during the seizure cycle: towards an on-line accumulated energy.

OBJECTIVE: Increases in accumulated energy on intracranial EEG are associated with oncoming seizures in retrospective studies, supporting the idea that seizures are generated over time. Published seizure prediction methods require comparison to 'baseline' data, sleep staging, and selecting seizures that are not clustered closely in time. In this study, we attempt to remove these constraints by using a continuously adapting energy threshold, and to identify stereotyped energy variations through the seizure cycle (inter-, pre-, post- and ictal periods). METHODS: Accumulated energy was approximated by using moving averages of signal energy, computed for window lengths of 1 and 20 min, and an adaptive decision threshold. Predictions occurred when energy within the shorter running window exceeded the decision threshold. RESULTS: Predictions for time horizons of less than 3h did not achieve statistical significance in the data sets analyzed that had an average inter-seizure interval ranging from 2.9 to 8.6h. 51.6% of seizures across all patients exhibited stereotyped pre-ictal energy bursting and quiet periods. CONCLUSIONS: Accumulating energy alone is not sufficient for predicting seizures using a 20 min running baseline for comparison. Stereotyped energy patterns through the seizure cycle may provide clues to mechanisms underlying seizure generation. SIGNIFICANCE: Energy-based seizure prediction will require fusion of multiple complimentary features and perhaps longer running averages to compensate for post-ictal and sleep-induced energy changes.

Algorithms↗