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PubMed1997

Neuropsychological predictors of adaptive kitchen behavior in geriatric psychiatry inpatients.

This study examined the degree to which demographic variables, psychiatric diagnosis, depression rating, and neuropsychological test performance predict adaptive kitchen behavior in geriatric psychiatry patients and normal elderly volunteers. Amixed group of 27 participants including 8 normal volunteers and 19 geriatric psychiatry inpatients underwent psychiatric evaluation, neuropsychological testing, and a kitchen skills assessment conducted in a natural setting. Both depression and dementia were prevalent among patients. The kitchen skills assessment was abnormal in 69% of patients, compared to none of the normal volunteers. Estimated premorbid IQs, psychiatric diagnosis, and neuropsychological test scores significantly predicted the pass/fail status on the kitchen skills assessment, but there was no effect for age, education, gender, or depression. The discriminant function analysis classified 92% of cases, and the canonical correlation coefficient was .84. Of the neuropsychological tests employed in the study, two tests involving visuospatial processing and attention were retained in the discriminant function analysis. The results are consistent with previous studies that suggest that visuospatial tasks are more predictive of instrumental activities of daily living than are cognitive tasks emphasizing verbal and memory abilities. In addition, we conclude that neuropsychological test data are useful and valid for the purpose of guiding clinical judgments regarding activities of daily living in geriatric psychiatry patients.

Activities of Daily Living↗
PubMed1985

Auditory adaptation: notes on power and parabolic curve fitting across intensity: II.

The classic Simultaneous Dichotic Loudness Balance (SDLB) procedure for the study of auditory adaptation was used by Weiler and Hood (1977) in a successful test of a model for predicting adaptation in db at intensities above the initial baseline values, using a linear approximation across levels. When Balzer et al (Brit. J. Audiol., 1984, 18, 49-50) fitted curves for simple baseline adaptation data from four studies based on SDLB data, they reported good fits for the Gompertz technique and for a parabolic formula, but did not test the relative goodness of fit for the linear formula, nor for power approximations as Stevens (1975) might have proposed. The present study makes use of the data used by Balzer et al but examines a linear fit as well as two approximations to Stevens' power law. The present finding that the linear approximation is the least efficient examined would suggest that the Weiler and Hood model should be re-examined to determine the degree to which the model can be improved by use of a curvilinear baseline fit. In addition, it might be noted that the curvilinear formulae, of necessity, involve two or more stages. It is the the current effort of this laboratory to determine whether this reflects a multifactor basis to the classic SDLB adaptation, as well as results from other adaptation techniques.

Adaptation, Physiological↗
PubMed2001

Ethnicity, coping, and distress among Korean Americans, Filipino Americans, and Caucasian Americans.

The authors examined appraisal, coping, and distress among Korean American, Filipino American, and Caucasian American Protestants. No interaction effects emerged among ethnic groups, but there were significant ethnic main effects for appraisal and coping. Compared with the Caucasian Americans, both Asian American groups appraised stressors as more challenging, and the Korean Americans appraised them also as greater losses. Both Asian American groups reported using more strategies of accepting responsibility, religious coping, distancing, and escape-avoidance than the Caucasian Americans did; the Filipino Americans also reported more problem-solving strategies than the Caucasian Americans. For all participants, challenge appraisals predicted adaptive coping (problem solving and positive reappraisal) and less distress. Problem solving, seeking social support, and positive reappraisal predicted less distress; self-control, accepting responsibility, and escape-avoidance predicted greater distress. The authors stressed the value of assessing ethnicity in coping research.

Adaptation, Psychological↗
PubMed1985

The theory of homeoviscous adaptation of membranes applied to deep-sea animals.

Deep-sea organisms live at high pressure and low temperature. These two factors increase the order of the bilayer in cell membranes, and, on the basis of the homeoviscous theory of membrane adaptation, predictions are made of the fluidity and composition of deep-sea membranes. Some of the predictions have been tested using membranes from deep-sea fish and some of the results are consistent with the theory. The conclusion is that the theory receives general support from the deep sea and, conversely, adaptation of membranes to high pressure can be profitably investigated in a more detailed manner by testing further predictions based on the homeoviscous concept.

Adaptation, Physiological↗
PubMedDate not supplied

Surveillance and screening of American cutaneous leishmaniasis by Colombian primary health care workers using a clinical prediction rule.

Confirmed cases of American cutaneous leishmaniasis (ACL) and other dermatological diseases were evaluated in Colombia with a clinical prediction rule independently by 3 types of evaluators: community health volunteer (CHV), practical nurse (PN) and programme physician (PP). The adapted prediction rule included 6 variables based upon clinical-historical information. The screening instrument was a rotating tower of coloured squares, one colour for each variable. A score ranging from 0 to 7, and a cutoff point of > or = 4 was selected for ACL classification (sensitivity 94.3%, specificity 53.3% and efficiency 80.3%). Disease classification, total score, and variable-specific score obtained by CHVs and PNs were compared to those obtained by a PP. The impact on case detection in the study area was assessed. Both types of primary health worker had a high agreement with the PP (sensitivity) on the classification of patients with ACL by score, CHV (92.3%) and PN (93.3%). Case detection of ACL increased 3-fold over that observed one year earlier. This screening instrument and prediction rule, when incorporated into a community surveillance programme for ACL, can facilitate greater case detection and appropriate referral for more-specific diagnostic procedures.

Colombia↗
PubMed1992

Prediction of bone adaptation in the ulnar-osteotomized sheep's forelimb using an anatomical finite element model.

A method for the prediction of the time-course of bone adaptation based on an alternative hypothesis of strength optimization has been previously investigated and developed by Prendergast and Taylor. This paper extends our work in the study of the effectiveness of this bone adaptation model in predicting similar bone remodelling to that observed in animal experiments. In particular the experimental work which has been modelled is that of Lanyon, Goodship, Pye and McFie. An anatomical finite element model of the sheep's forelimb has been generated for this purpose and is used to estimate stresses in the bone structure for the normal and osteotomized condition. The propensity for remodelling of the altered bone structure is predicted using the proposed remodelling law for the new stress field in the bone structure. The preliminary results indicate an initial bone adaptation pattern similar to that observed experimentally without the necessity to use arbitrarily different constants for the endosteal and periosteal surfaces. We therefore suggest that the remodelling law based on damage and repair gives a better predictive model of bone adaptation than previous models.

Adaptation, Physiological↗
PubMed2006

Evolutionary neuropathology and Down syndrome: an analysis of the etiological and phenotypical characteristics of Down syndrome suggests that it may represent an adaptive response to severe maternal deprivation.

This paper will suggest that the Down syndrome phenotype would have been well suited, physiologically, for a deprived environment and that it may represent a predictive, adaptive response to severe maternal deprivation. A trisomy of the 21st chromosome, prior to, or at conception is responsible for Down syndrome and is known to increase in incidence with advanced maternal age. One out of 11 mothers over the age of 50 conceives a Down syndrome baby, compared to one in one thousand at age 30. This article emphasizes that an older mother is more likely to die before she is able to provide the parental investment necessary to produce an ecologically self-sufficient offspring. Prolonged maternal investment is known to be essential for hunter-gatherers to master the skill intensive food procurement techniques that they will need in order to become independent of their mothers. Because Down syndrome individuals are much more likely to be born to older mothers, they must have been routinely deprived of maternal investment in the human environment of evolutionary adaptedness. This consistent paring of maternal deprivation to trisomy 21 conceptions, over time, may have caused natural selection to favor genes responsible for the energy conserving traits seen in modern day Down syndrome. These traits include muscle hypotonia, decreased cerebral metabolism, decreased hippocampal volume, a strong propensity for obesity and growth hormone and thyroid hormone paucity. Such a "thrifty phenotype" may have allowed Down syndrome individuals to become independent of their mothers at a far earlier age and allowed them to forgo the skill intensive ecological niche that non-trisomic humans are phenotypically suited for in order to take up a less cognitively and physically rigorous one.

Adaptation, Physiological↗
PubMed1996

Third-order reverse correlation analysis of muscle spindle primary afferent fiber responses to random muscle stretch.

The response of primary muscle spindle afferent fibers to muscle stretch is nonlinear. Now spindle responses (trains of action potentials) to band-limited Gaussian white noise length perturbations of the gastrocnemius muscles (input signal) are described in cats. The input noise upper cutoff frequency was clearly above the frequency range of physiological length changes in cat hindleg muscles. The input-output relation was analyzed by means of peri-spike averages (PSAs), which could be shown to correspond to the kernels of Wiener's white noise approach to systems identification. The present approach (the reverse correlation analysis) was applied up to the third order. An experiment consisted of two recordings: one (the source recording) to determine PSAs and the other (the test recording) to provide an input signal for predicting responses. The predictions of different orders were compared with the actual neuronal response (the observation) of the test recording. Four different approximation procedures were developed to adapt prediction and observation and to determine weighting factors for the predictions of different orders. The approximations also yielded the value of the power density P of the input noise signal: at a variety of stimulus parameters, P from approximations had the same magnitude as P determined directly from the input signal amplitude spectrum. The prediction of a sequence of action potentials improved the higher the order of components. 37 of 42 action potentials of a test recording (the observation) could be confidently predicted from PSAs or kernels. Compared with the size of the linear first-order prediction curve, the relative sizes of the second and third-order prediction curves were: 1.0:0.47:0.26.

Action Potentials↗
PubMed1986

A molecular mechanism for sensory adaptation based on ligand-induced receptor modification.

Physiological responses mediated by cell-surface receptors frequently adapt or "desensitize" (i.e., terminate despite persistent occupancy of receptors by ligand). Binding of ligands to the external domains of a wide variety of surface receptors induces covalent modification of their cytoplasmic domains. A mechanism is presented in which the variety of receptor states generated by ligand binding and covalent modification act together to regulate physiological responsiveness. The development of the model is guided by observations of adaptation for chemotaxis in Escherichia coli and adenylate cyclase activation in Dictyostelium. The general features of the marked response and eventual exact adaptation predicted by the model match those observed in the experimental systems.

Adaptation, Physiological↗
PubMed2006

Disparate maturation adaptations to size-dependent mortality.

Body size is an important determinant of resource use, fecundity and mortality risk. Evolution of maturation size in response to size-dependent selection is thus a fundamental part of life-history theory. Increased mortality among small individuals has previously been predicted to cause larger maturation size, whereas increased mortality among large individuals is expected to have the opposite effect. Here we use a continuously size-structured model to demonstrate that, contrary to these widespread expectations, increased mortality among small individuals can have three alternative effects: maturation size may increase, decrease or become evolutionarily bistable. We show that such complex responses must be reckoned with whenever mortality is size-dependent, growth is indeterminate, reproduction impairs growth and fecundity increases with size. Predicting adaptive responses to altered size-dependent mortality is thus inherently difficult, since, as demonstrated here, such mortality cannot only reverse the direction of adaptation, but also cause abrupt shifts in evolutionarily stable maturation sizes.

Adaptation, Biological↗
PubMed2000

Walking infants adapt locomotion to changing body dimensions.

Infants acquire independent mobility amidst a flux of body growth. Changes in body dimensions and variations in the ground change the physical constraints on keeping balance. The study examined whether toddlers can adapt to changes in their body dimensions and variations in the terrain by loading them with lead weights and observing how they navigated safe and risky slopes. Experiment 1 verified the reliability of a new psychophysical procedure for testing infants' responses in 2 experimental conditions. In Experiment 2, this procedure was used to compare infants' responses on slopes in feather-weight and lead-weight conditions. The lead weights impaired infants' ability to walk down slopes. Babies adapted to altered body dimensions by treating the same degree of slope as safe in the feather-weight condition but as risky in the lead-weight condition. Exploratory activity on the starting platform predicted adaptive responses on risky slopes.

Adaptation, Physiological↗
PubMed2002

Tissue adaptation to physical stress: a proposed "Physical Stress Theory" to guide physical therapist practice, education, and research.

The purpose of this perspective is to present a general theory--the Physical Stress Theory (PST). The basic premise of the PST is that changes in the relative level of physical stress cause a predictable adaptive response in all biological tissue. Specific thresholds define the upper and lower stress levels for each characteristic tissue response. Qualitatively, the 5 tissue responses to physical stress are decreased stress tolerance (eg, atrophy), maintenance, increased stress tolerance (eg, hypertrophy), injury, and death. Fundamental principles of tissue adaptation to physical stress are described that, in the authors' opinion, can be used to help guide physical therapy practice, education, and research. The description of fundamental principles is followed by a review of selected literature describing adaptation to physical stress for each of the 4 main organ systems described in the Guide to Physical Therapist Practice (ie, cardiovascular/pulmonary, integumentary, musculoskeletal, neuromuscular). Limitations and implications of the PST for practice, research, and education are presented.

Adaptation, Physiological↗
PubMed2006

Homoploid hybrid speciation in an extreme habitat.

According to theory, homoploid hybrid speciation, which is hybrid speciation without a change in chromosome number, is facilitated by adaptation to a novel or extreme habitat. Using molecular and ecological data, we found that the alpine-adapted butterflies in the genus Lycaeides are the product of hybrid speciation. The alpine populations possess a mosaic genome derived from both L. melissa and L. idas and are differentiated from and younger than their putative parental species. As predicted, adaptive traits may allow for persistence in the environmentally extreme alpine habitat and reproductively isolate these populations from their parental species.

Adaptation, Physiological↗
PubMed1990

The minor events approach to stress: support for the use of daily hassles.

Everyday minor stressors (hassles) have been proposed as an alternative to major life-events as a measure of stress. This article examines three aspects of hassles as a stress measure: group contextual differences in hassles reported, the stability and consistency of hassles over time, and the effectiveness of hassles in predicting adaptational outcomes. Results showed that there are clear contextual differences in hassles. Groups report quite different patterns of hassles reflecting their particular social contexts. These patterns also appear to be stable across time, probably as a result of consistency in both group roles and situational factors. Finally, hassles are found to be substantially better than life-events in predicting psychological well-being and mental health dimensions. Taken together, these findings support the use of hassles as a valid and reliable measure of stress which has significant relationships to important adaptational outcomes.

Adaptation, Psychological↗
PubMed2006

Effects of cognitive adaptation on the expectation-burnout relationship among nurses.

Burnout has traditionally been thought to result from unrealistically high expectations although research has provided only equivocal support. We explored the impact of cognitive adaptation disposition, including mastery, optimism, and self-esteem, on the expectations-burnout relationship. Nurses (N = 341) who were recruited at professional conferences completed questionnaires that assessed cognitive adaptation, burnout, and initial and current expectations of control. As expected, cognitive adaptation predicted fewer unmet expectations of control, which in turn predicted lower burnout. In addition, optimism and self-esteem predicted lower burnout regardless of perceived initial expectations, whereas mastery lessened the negative consequences of initially high expectations on burnout.

Adaptation, Psychological↗
PubMed2006

[Prognostic estimation in critical patients. Validation of a new and very simple system of prognostic estimation of survival in an intensive care unit].

OBJECTIVE: To make the validation of a new system of prognostic estimation of survival in critical patients (EPEC) seen in a multidisciplinar Intensive care unit (ICU). DESIGN AND SCOPE: Prospective analysis of a patient cohort seen in the ICU of a multidisciplinar Intensive Medicine Service of a reference teaching hospital with 19 beds. PATIENTS AND METHOD: Four hundred eighty four patients admitted consecutively over 6 months in 2003. Data collection of a basic minimum data set that includes patient identification data (gender, age), reason for admission and their origin, prognostic estimation of survival by EPEC, MPM II 0 and SAPS II (the latter two considered as gold standard). Mortality was evaluated on hospital discharge. EPEC validation was done with analysis of its discriminating capacity (ROC curve), calibration of its prognostic capacity (Hosmer Lemeshow C test), resolution of the 2 x 2 Contingency tables around different probability values (20, 50, 70 and mean value of prognostic estimation). The standardized mortality rate (SMR) for each one of the methods was calculated. Linear regression of the EPEC regarding the MPM II 0 and SAPS II was established and concordance analyses were done (Bland-Altman test) of the prediction of mortality by the three systems. RESULTS: In spite of an apparently good linear correlation, similar accuracy of prediction and discrimination capacity, EPEC is not well-calibrated (no likelihood of death greater than 50%) and the concordance analyses show that more than 10% of the pairs were outside the 95% confidence interval. CONCLUSION: In spite of its ease of application and calculation and of incorporating delay of admission in ICU as a variable, EPEC does not offer any predictive advantage on MPM II 0 or SAPS II, and its predictions adapt to reality worse.

Adult↗
PubMed2005

Continuity and change from early childhood to adolescence in autism.

BACKGROUND: This longitudinal study of 48 children diagnosed with autism at 2-5 years of age was designed to test the hypothesis that diagnosis would remain stable for most of the sample but that there would be improvements in symptom severity, adaptive behavior, and emotional responsiveness in adolescence. METHODS: A sample of children with autism assessed in both early and middle childhood were observed in late adolescence with the Autism Diagnostic Observation Scale (ADOS) and their parents were administered the Autism Diagnostic Interview-Revised (ADI-R) and the Vineland Adaptive Behavior Scale. RESULTS: All but 2 adolescents (46 of 48) met lifetime criteria for autism according to the ADI-R, and all but 4 adolescents (40 of 44) met criteria for autism spectrum disorder on the ADOS. In contrast to the continuity in diagnosis, parents described improvements in social interactions, repetitive/stereotyped behaviors, adaptive behaviors, and emotional responsiveness to others' distress in adolescence compared to middle childhood. High-functioning adolescents with autism showed more improvement in these domains than low-functioning adolescents with autism. The extent to which the adolescents were observed to be socially engaged with their peers in school in middle childhood predicted adaptive behavior skills even when intelligence level was statistically constrained. CONCLUSIONS: The developmental trajectory of children with autism appears to show both continuity and change. In this sample, most individuals continued to be diagnosed in the autism spectrum but parents reported improvements in adolescence. The results suggest that social involvement with peers improves adaptive behavior skills, and this argues for focusing intervention programs in this area. In addition, it is clear that high-functioning adolescents improve more than low-functioning individuals not only in cognitive abilities but also in social interaction skills. Thus, any early intervention that impacts the cognitive abilities of young children with autism is likely to have a parallel influence on their social skills as they mature into late adolescence and early adulthood.

Adaptation, Psychological↗