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PubMed1998

The relationship between housing characteristics, emotional well-being and the personal empowerment of psychiatric consumer/survivors.

In this research, we examine the relationships between the housing characteristics and dimensions of community adaptation for 107 psychiatric consumer/survivors. Hypotheses about which housing characteristics best predict which dimensions of adaptation were made based on previous research and theory. Using a longitudinal research design, we found, after controlling for demographic variables and prior adaptation, that the number of living companions, housing concerns, and having a private room all significantly predicted different dimensions of community adaptation. The findings partially support our theoretical expectations and illuminate the relationship between physical, social and organizational aspects of community-based housing and the adaptation of psychiatric consumer/survivors. We discuss the implications of the results for policy and practice in providing housing for this population.

Activities of Daily Living↗

PubMed2003

A two-year follow-up study and prospective evaluation of the DSM-IV axis V.

A six-month cohort of general adult psychiatric inpatients was followed for up to two years to evaluate outcome and contrast the validity of DSM-IV measures of adaptive functioning-the Global Assessment of Functioning (GAF), the Social and Occupational Functioning Assessment Scale (SOFAS), and the Global Assessment of Relational Functioning Scale (GARF). Detailed data, including quality-of-life ratings and DSM-IV axis I and V codes, were collected by interview and self-report questionnaires for 53 study participants. Patients' retrospective ratings of the care they received were not predictive of outcome. Adaptive functioning at discharge was predictive of both severity of illness and social functioning at follow-up. The SOFAS had the strongest concurrent and predictive validity, the latter both for length of initial inpatient stay and two-year outcome.

Adaptation, Psychological↗

PubMed2006

An adaptive input-output modeling approach for predicting the glycemia of critically ill patients.

In this paper we apply system identification techniques in order to build a model suitable for the prediction of glycemia levels of critically ill patients admitted to the intensive care unit. These patients typically show increased glycemia levels, and it has been shown that glycemia control by means of insulin therapy significantly reduces morbidity and mortality. Based on a real-life dataset from 15 critically ill patients, an initial input-output model is estimated which captures the insulin effect on glycemia under different settings. To incorporate patient-specific features, an adaptive modeling strategy is also proposed in which the model is re-estimated at each time step (i.e., every hour). Both one-hour-ahead predictions and four-hours-ahead simulations are executed. The optimized adaptive modeling technique outperforms the general initial model. To avoid data selection bias, 500 permutations, in which the patients are randomly selected, are considered. The results are satisfactory both in terms of forecasting ability and in the clinical interpretation of the estimated coefficients.

Aged↗

PubMed2005

Recognition of merged characters based on forepart prediction, necessity-sufficiency matching, and character-adaptive masking.

Merged characters are the major cause of recognition errors. We classify the merging relationship between two involved characters into three types: "linear," "nonlinear," and "overlapped." Most segmentation methods handle the first type well, however, their capabilities of handling the other two types are limited. The weakness of handling the nonlinear and overlapped types results from character segmentation by linear, usually vertical, cuts assumed in these methods. This paper proposes a novel merged character segmentation and recognition method based on forepart prediction, necessity-sufficiency matching and character-adaptive masking. This method utilizes the information obtained from the forepart of merged characters to predict candidates for the leftmost character, and then applies character-adaptive masking and character recognition to verifying the prediction. Therefore, the arbitrary-shaped cutting path will follow the right shape of the leftmost character so as to preserve the shape of the next character. This method handles the first two types well and greatly improves the segmentation accuracy of the overlapped type. The experimental results and the performance comparisons with other methods demonstrate the effectiveness of the proposed method.

Algorithms↗

PubMed2005

Recombination enhances protein adaptation in Drosophila melanogaster.

Evolutionary theory predicts that the rate and level of adaptation will be enhanced in sexual relative to asexual genomes because sexual recombination facilitates the elimination of deleterious mutations and the fixation of beneficial ones by natural selection. To date, the most compelling evidence for this prediction comes from experimental evolution studies and from loci completely lacking recombination, such as those on Y chromosomes, which often show reduced adaptation and even degeneration. Here, by analyzing replacement and silent DNA polymorphism and divergence at 98 loci, I show that recombination increases the efficacy of protein adaptation throughout the genome of the fruit fly Drosophila melanogaster. Genes residing in genomic regions with reduced recombination rates suffer a greater load of segregating, mildly deleterious mutations and fix fewer beneficial mutations than genes residing in regions with higher recombination rates. These findings suggest that the capacity to respond to natural selection varies with recombination rate across the genome, consistent with theory on the evolutionary advantages of sex and recombination.

Adaptation, Biological↗

PubMed2006

Comparative performance of linear and nonlinear neural networks to predict irregular breathing.

Breathing adaptation during external-beam radiotherapy is a matter of great concern because uncompensated tumour motion requires extended treatment margins that endanger sensitive tissue. Compensation strategies include beam gating, collimator tracking and robotic beam re-alignment. All of these schemes have a system latency of up to several hundred milliseconds, which calls in turn for predictive control loops. Irregularities in breathing make prediction difficult. We have evaluated the performance of two classes of control loop algorithms-the linear adaptive filter and the adaptive nonlinear neural network-for highly irregular patient breathing behaviours. The neural network demonstrated robust adaptability to all of the observed breathing patterns while the linear filter failed in a significant percentage of cases. For those cases where the linear filter could function, it made less accurate predictions than the neural network. Because the neural network presents no additional computational burden in the control loop we conclude that it is the preferred choice among heuristic predictive algorithms.

Algorithms↗

PubMedDate not supplied

Individualization of 5-fluorocytosine therapy.

Using a convenient and fast HPLC procedure we determined serum concentrations of the fungistatic agent 5-fluorocytosine (5-FC) in 375 samples from 60 patients treated with this drug. The mean trough concentration (n = 127) was 64.3 mg/l (range: 11.8-208.0 mg/l), the mean peak concentration (n = 122) was 99.9 mg/l (range: 25.6-263.8 mg/l), the mean nonpeak/nontrough concentration (n = 126) was 80.1 mg/l (range: 10.5-268.0 mg/l). Totally 134 (35.7%) samples were outside the therapeutic range (25-100 mg/l), 108 (28.8%) being too high, 26 (6.9%) being too low. Forty-four (73%) patients showed 5-FC serum concentrations outside the therapeutic range at least once during the treatment course. In a prospective study we performed 65 dosage predictions on 30 patients by use of a 3-point method previously developed for aminoglycoside dosage adaptation. The mean absolute prediction error of the dosage adaptation was +0.7 mg/l (range: -26.0 to +28.0 mg/l). The root mean square prediction error was 10.7 mg/l. The mean predicted concentration (65.3 mg/l) agreed very well with the mean measured concentration (64.6 mg/l). The frequency distribution of 5-FC serum concentrations indicates that 5-FC monitoring is important. The applied pharmacokinetic method allows individual adaptations of 5-FC dosage with a clinically acceptable prediction error.

Adolescent↗

PubMed1990

Femoral strain adaptation after total hip replacement: a comparison of cemented and porous ingrowth components in canines.

The purpose of this study was to investigate if experimental strain analysis is predictive of femoral adaptation after total hip replacement (THR). Ten large adult dogs underwent unilateral THR with identical implants. Five implants were press fit for porous ingrowth fixation, and five were cemented. Four months after surgery femora were harvested. Strain gauge rosettes were applied to the femora at eight proximal locations. Femora were compressively loaded on the head of the femur or femoral component. Strain data represented three conditions: preoperative, acutely postoperative, and four-month postoperative. The unoperated femur of each dog was used to simulate preoperative and acutely postoperative behavior of the contralateral implanted femur. Strains from each condition were compared. Transverse femoral sections were obtained through the levels of the strain gauges. Fine detailed radiographs were used to quantify morphological changes. Results showed cemented and uncemented implantations produce similar trends but different amounts of bone adaptation. Adaptations were generally consistent in direction with strain perturbations caused by implantation, but the extent of adaptation did not strongly correlate with the magnitude of perturbations. Also, there was no consistent trend towards normalization of altered strains. Results suggest that strain perturbations after THR may be mechanical triggers for morphological changes, but caution is required when predicting the extent of these changes or the autoregulatory role of strain.

Adaptation, Physiological↗

PubMed1993

Predictive validity of a Spanish-language adapted version of the Anton Brenner Developmental Gestalt Test of School Readiness.

For an adapted version of the Anton Brenner Developmental Gestalt Test of School Readiness, developed for experimental use in Costa Rica, the present objective was to ascertain its predictive validity. With 312 preschool children during the first semester and at the end of kindergarten, the relationship between test scores and failing or passing first grade was examined and found similar. The average hit rate (percentage of children with and without school problems who were classified correctly) was 84%, the test's sensitivity (percentage of children with difficulties identified correctly) was 23%, and its specificity (percentage of children correctly identified who did not have school problems in first grade) was 97%. The test showed almost a 7:1 ratio for misclassifying false positives and false negatives. It seems advantageous to use the test in the first semester to have time to remedy difficulties during kindergarten.

Child Development↗

PubMed2003

Protein evolution and codon usage bias on the neo-sex chromosomes of Drosophila miranda.

The neo-sex chromosomes of Drosophila miranda constitute an ideal system to study the effects of recombination on patterns of genome evolution. Due to a fusion of an autosome with the Y chromosome, one homolog is transmitted clonally. Here, I compare patterns of molecular evolution of 18 protein-coding genes located on the recombining neo-X and their homologs on the nonrecombining neo-Y chromosome. The rate of protein evolution has significantly increased on the neo-Y lineage since its formation. Amino acid substitutions are accumulating uniformly among neo-Y-linked genes, as expected if all loci on the neo-Y chromosome suffer from a reduced effectiveness of natural selection. In contrast, there is significant heterogeneity in the rate of protein evolution among neo-X-linked genes, with most loci being under strong purifying selection and two genes showing evidence for adaptive evolution. This observation agrees with theory predicting that linkage limits adaptive protein evolution. Both the neo-X and the neo-Y chromosome show an excess of unpreferred codon substitutions over preferred ones and no difference in this pattern was observed between the chromosomes. This suggests that there has been little or no selection maintaining codon bias in the D. miranda lineage. A change in mutational bias toward AT substitutions also contributes to the decline in codon bias. The contrast in patterns of molecular evolution between amino acid mutations and synonymous mutations on the neo-sex-linked genes can be understood in terms of chromosome-specific differences in effective population size and the distribution of selective effects of mutations.

Animals↗

PubMed2004

Predicting respiratory motion for four-dimensional radiotherapy.

Adapting radiation delivery to respiratory motion is made possible through corrective action based on real-time feedback of target position during respiration. The advantage of this approach lies with its ability to allow tighter margins around the target while simultaneously following its motion. A significant hurdle to the successful implementation of real-time target-tracking-based radiation delivery is the existence of a finite time delay between the acquisition of target position and the mechanical response of the system to the change in position. Target motion during the time delay leads to a resultant lag in the system's response to a change in tumor position. Predicting target position in advance is one approach to ensure accurate delivery. The aim of this manuscript is to estimate the predictive ability of sinusoidal and adaptive filter-based prediction algorithms on multiple sessions of patient respiratory patterns. Respiratory motion information was obtained from recordings of diaphragm motion for five patients over 60 sessions. A prediction algorithm that employed both prediction models-the sinusoidal model and the adaptive filter model-was developed to estimate prediction accuracy over all the sessions. For each session, prediction error was computed for several time instants (response time) in the future (0-1.8 seconds at 0.2-second intervals), based on position data collected over several signal-history lengths (1-7 seconds at 1-second intervals). Based on patient data included in this study, the following observations are made. Qualitative comparison of predicted and actual position indicated a progressive increase in prediction error with an increase in response time. A signal-history length of 5 seconds was found to be the optimal signal history length for prediction using the sinusoidal model for all breathing training modalities. In terms of overall error in predicting respiratory motion, the adaptive filter model performed better than the sinusoidal model. With the adaptive filter, average prediction errors of less than 0.2 cm (1sigma) are possible for response times less than 0.4 seconds. In comparing prediction error with system latency error (no prediction), the adaptive filter model exhibited lesser prediction errors as compared to the sinusoidal model, especially for longer response time values (>0.4 seconds). At smaller response time values (<0.4 seconds), improvements in prediction error reduction are required for both predictive models in order to maximize gains in position accuracy due to prediction. Respiratory motion patterns are inherently complex in nature. While linear prediction-based prediction models perform satisfactorily for shorter response times, their prediction accuracy significantly deteriorates for longer response times. Successful implementation of real-time target-tracking-based radiotherapy requires response times less than 0.4 seconds or improved prediction algorithms.

Algorithms↗

PubMed2005

Improving binding mode predictions by docking into protein-specifically adapted potential fields.

The development of a protein-specifically adapted objective function for docking is described. Structural and energetic information about known protein-ligand complexes is exploited to tailor knowledge-based potentials using a "reverse", protein-based CoMFA-type (=AFMoC) approach. That way, effects due to protein flexibility and information about multiple solvation schemes can be implicitly incorporated. Compared to the application of AFMoC for binding affinity predictions, a Shannon entropy based column filtering of the descriptor matrix and the capping of adapted repulsive potentials within the binding site have turned out to be crucial for the success of this method. The new developed approach (AFMoC(obj)) was validated on a data set of 66 HIV-1 protease inhibitors, for which experimental structural information was available. Convincingly, for ligands with up to 20 rotatable bonds, in more than 75% of all cases a binding mode below 2 A rmsd has been identified on the first scoring rank when AFMoC(obj)-based potentials were used as the objective function in AutoDock. With respect to nonadapted DrugScore or AutoDock fields, the binding mode prediction accuracy was significantly improved by 14%. Noteworthy, very similar results were obtained for training and test set compounds, demonstrating the strength and robustness of this method. Implications of our findings for binding affinity predictions and its usage in virtual screening are further discussed.

Binding Sites↗

PubMed1982

[Modification of psychosocial adjustment by terminal disease].

Psychosocial adaption during or after somatic illness is relatively little studied--quite in difference to the better known psychosocial predictors of somatic illness. This study is concerned with a group of 31 female patients who suffered from a terminal vascular disease (primary vascular pulmonary hypertension)--an iatrogenic disease which with high probability is the consequence of a drug for weight reducing (Menocil), prescribed by their family doctors to these moderate overweight middle aged women. Psychosocial adaptions was assessed on a 5-point-scale, including the following dimensions: work-situation, socio-economic conditions, family adaption, social activities. Psychosocial adaption before illness was very good (just 10% below maximal values). Two or three years after illness started, however, there was a highly significant drop in all dimensions (most significant in "work" and "social activities"). To some extent success or failure of psychosocial adaption had a predictive power for the terminal course of this illness. Possible interaction between course of illness and psychosocial adaption is discussed and illustrated. There was also a significant correlation between psychosocial adaption and defense-processes.

Adult↗

PubMed2001

Adaptive sex ratios and parent-offspring conflict.

Studies testing the theoretical prediction that birds would adaptively vary the sex ratio of their offspring either supported theoretical predictions or simply found a 1:1 sex ratio. Four recent papers, in particular one by Kate Oddie, of Great Tit nestling sex ratios, however, found that, when conditions are poor, the sex ratio is male biased, opposite of what was predicted by theory. The development of molecular markers to sex birds using minute amounts of blood has allowed experiments that help us to explain this apparent anomaly.

Journal Article↗

PubMed2005

Predictive validity of the Chronic Pain Coping Inventory in subacute low back pain.

The Chronic Pain Coping Inventory (CPCI) was developed to assess eight behavioral coping strategies hypothesized to be important for pain adaptation. But the predictive validity of the CPCI has yet to be tested in a longitudinal study. Here, 321 workers on sick leave after a work accident affecting the low back pain (LBP) region completed the CPCI during the subacute stage (T1) of LBP as well as the Catastrophizing scale of the Coping Strategies Questionnaire (CSQ). Disability, pain intensity and depressive mood were assessed simultaneously as well as 6 months later (T2). Work status was also determined at follow-up. Hierarchical regression analyses revealed that the CPCI (Guarding scale) predicted T1 disability and T2 disability (Relaxation scale), but T1 disability was the best predictor of T2 disability. For T1 pain intensity, the CSQ's Catastrophizing dimension was the best predictor and the CPCI Guarding scale added a small contribution. T1 pain intensity was the best predictor of T2 pain intensity. Catastrophizing and Guarding were the most strongly associated with depressive mood at T1 but at T2, only depressive mood at T1 predicted this same variable. Results indicated also that the Guarding and Catastrophizing scales were able to predict future work status. The present study clearly reveals the usefulness of Guarding from the CPCI and Catastrophizing from the CSQ, when predicting different outcomes of adjustment to low back pain.

Activities of Daily Living↗

PubMed2005

Coping strategies as predictors of psychosocial adaptation in a sample of elderly veterans with acquired lower limb amputations.

This study examines the contribution of demographic/amputation-related variables and coping strategies to the prediction of psychosocial adaptation in veterans with acquired lower limb amputations. Multiple indicators of the psychosocial adjustment of 796 individuals in the UK aged between 26-92 years with lower limb amputations were assessed. Hierarchical linear regressions were performed to investigate relationships between demographic/amputation-related variables (i.e. age, time since amputation, amputation level and amputation aetiology), the dimensions of coping (namely problem solving, seeking social support and avoidance) and self-reported adaptation to amputation, as well as symptoms of intrusion, anxiety and depression. Results indicated that coping styles were important predictors of psychosocial adaptation. Avoidance was strongly associated with psychological distress and poor adjustment. In contrast, problem solving was negatively associated with depressive and anxious symptomatology whereas seeking social support was negatively associated with symptoms of depression and positively associated with social adaptation. These findings suggest the potential for interventions designed to promote particular coping strategies to improve psychosocial outcomes.

Adaptation, Psychological↗

PubMed1986

The Glenn A. Fry award lecture: adaptive regulation of accommodative vergence and vergence accommodation.

The tonic resting level of accommodation, measured with an objective infrared optometer in an open-loop state (pinhole pupil or empty field), was increased by more than 1.75 D from baseline measures of resting focus after adapting monocularly for 1 min to a 2 D minus lens. The accommodative aftereffect disappeared in darkness, but returned when a visible stimulus reappeared in the open-loop state. Stimulation of disparity vergence with 10 delta, while accommodation was in an open-loop state, also increased the resting focus of accommodation. Similarly, the tonic resting level of vergence became more esophoric after adapting for less than 1 min to base-out prism or to a minus lens presented while the vergence loop was opened. The effects of tonic accommodation on accommodative vergence and the effects of tonic vergence on vergence accommodation were investigated with the temporal frequency responses of the AC/A and CA/C ratios to sinusoidal variations in blur (2 D) and disparity (10 delta), respectively. Accommodative vergence was unresponsive to low temporal frequency sinusoidal variations in blur (less than 0.1 Hz). Similarly, vergence accommodation was unresponsive to low temporal frequency sinusoidal variations in disparity. However, accommodative vergence and vergence accommodation were responsive to higher temporal frequency stimuli (up to 0.5 Hz). When negative feedback to the stimulated system (accommodation or vergence) was cancelled electronically, the low temporal frequency response increased for the AC/A and CA/C ratios, respectively. There was also a nonlinear increase of both AC/A and CA/C ratios as stimulus amplitude increased. It is hypothesized that the nonlinearity resulted from limitations of adaptation to small stimuli. An inverse complementary relation is suggested between the amplitude of the AC/A ratio and adaptable tonic accommodation, and between the amplitude of the CA/C ratio and adaptable tonic vergence. This model predicts that in this complementary relation, adaptable tonic elements would sustain motor responses of accommodation and vergence that were initiated by phasic elements and cross-link interactions. It also predicts that the AC/A and CA/C ratios would decrease in time as dynamic control shifted from the phasic to the adaptable tonic control mechanisms of accommodation and vergence, respectively.

Accommodation, Ocular↗

PubMedDate not supplied

Adaptation.

The term adaptation is used in biology in three different ways. It may refer to changes which occur at the cell and organ level, or at the individual level, or at the level of gene action and evolutionary processes. Adaptation by cells, especially nerve cells helps in: communication within the body, the distinguishing of stimuli, the avoidance of overload and the conservation of energy. The time course and complexity of these mechanisms varies. Adaptive characters of organisms, including adaptive behaviours, increase fitness so this adaptation is evolutionary. The major part of this paper concerns adaptation by individuals and its relationships to welfare. In complex animals, feed forward control is widely used. Individuals predict problems and adapt by acting before the environmental effect is substantial. Much of adaptation involves brain control and animals have a set of needs, located in the brain and acting largely via motivational mechanisms, to regulate life. Needs may be for resources but are also for actions and stimuli which are part of the mechanism which has evolved to obtain the resources. Hence pigs do not just need food but need to be able to carry out actions like rooting in earth or manipulating materials which are part of foraging behaviour. The welfare of an individual is its state as regards its attempts to cope with its environment. This state includes various adaptive mechanisms including feelings and those which cope with disease. The part of welfare which is concerned with coping with pathology is health. Disease, which implies some significant effect of pathology, always results in poor welfare. Welfare varies over a range from very good, when adaptation is effective and there are feelings of pleasure or contentment, to very poor. A key point concerning the concept of individual adaptation in relation to welfare is that welfare may be good or poor while adaptation is occurring. Some adaptation is very easy and energetically cheap and welfare can be very good when it is occurring. Other adaptation is difficult and may involve lower or higher level emergency physiological responses or abnormal behaviour, often with bad feelings such as pain or fear. In that case, welfare is poor or very poor even if complete adaptation eventually occurs and there is no long-term threat to the life of the individual. In some circumstances, adaptation may be unsuccessful, the individual is not able to cope, stress occurs and welfare is ultimately very poor.

Adaptation, Physiological↗