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PubMed1993

[Physical fitness and motor ability in obese boys 12 through 14 years of age].

Excess body fat has generally been considered to be an influential factor to physical fitness and motor ability in obese boys. However, little information is available on the physical fitness and motor ability in obese boys. The purpose of this study was to clarify characteristics of physical fitness and motor ability in obese boys. The subjects were three hundreds and five boys aged 12-14 years. Nineteen physical fitness and motor ability items were tested and skinfold thickness was measured at six sites. Bioelectrical impedance was measured using a tetrapolar impedance plethysmograph (Selco SIF-891). Body density was calculated from the formula of Kim et al. The results of comparison clearly indicated that the obese group was significantly poorer in 1,500-m run, 5-min run, 50-m run, running long jump and many other variables, but was superior only in back strength. To analyze the factorial structure in boys, principal factor analysis was applied to the correlation matrix which was calculated with 19 variables, and then five factors were extracted. The obese group was significantly poorer in total body endurance and muscular endurance than the non-obese group. From these results, it was confirmed that the excess body fat could be one of the most important factors that affects the state of many physical fitness and motor ability elements in obese boys. However, the relationships between physical fitness, motor ability and the degree of fatness seem to be rather complicated. A great deal of data should be accumulated for more detailed analysis on the influence of the excess body fat in obese boys.

Adolescent↗
PubMed1994

[Assessment of the activities of daily living age in elderly women].

The purpose of this study was to assess activities of daily living age in elderly. The subjects were 253 Korean elderly women, aged 60 to 91 years, all of whom were participants in an elderly school program managed by the Seoul City. Activities necessary for independence in daily living must be selected from various components. First of all, a questionnaire was administered to clarify the areas of activities of daily living in the elderly. Factor analysis with Normal Varimax criterion was applied to the data, and the factors extracted were interpreted as locomotion of whole body, manipulation of upper limb, manipulation of finger, and change of posture. Secondly, twenty-four performance tests related to the activities of daily living were selected. Principal component analysis was applied to the 24 x 24 correlation matrix, and first principal component was interpreted as total activities of daily living because of significantly heavy loadings with all variables. Principal component score decreased significantly with advancing age (r = -0.578). Multiple regression analysis revealed that out of the 24 variables examined, 5 were suitable for the assessment of the activities of daily living. The equation developed to determine the activities of daily living age (ADLA) was ADLA = 6.28 ADLS + 72.21 + Z, ADLS = -0.039x1 + 0.051x2 + 0.048x3 + 0.015x4 + 0.012x5 - 2.76, Z = 0.44 Age-31.45; where x1 = walking around two chairs in a figure 8, x2 = moving beans from one container to another using pincers, x3 = grip strength, x4 = raising the arms above the head while holding a bar, and x5 = balancing on one leg with eyes open.(ABSTRACT TRUNCATED AT 250 WORDS)

Activities of Daily Living↗
PubMed2003

Examination of the factor structure of center of foot pressure movement and cross-validity.

This study aimed to determine the factor structure of the center of foot pressure (CFP) movement during static upright posture, and to objectively categorize and summarize parameters to evaluate CFP movement. The subjects were 220 healthy young males and females. The measurement of CFP was carried out 3 times with 1 min rest and the mean of trials 2 and 3 was used for the analysis. The measurement device was an Anima's stabilometer G5500. The data sampling frequency was 20 Hz. Thirty-four parameters with high reliability were selected from the following 6 domains except for the center position which is a fundamental attribute: distance, distribution of amplitude, area, velocity, power spectrum, and body sway vector. Factor analysis (principal factor method and promax rotation) was applied to a correlation matrix consisting of 32 parameters. Four factors abstracted were interpreted as follows; unit time sway, front and back sway, left and right sway and high frequency band of power spectrum. The reliability coefficient (ICC=0.89-0.95) and the congruence coefficient (phi=0.80-0.97) between factors abstracted from the original and the cross-validity groups were very high. It was considered that the CFP movement consists of the above 4 factors that evaluate the amount of body sway and can be synthetically evaluated by them.

Biomechanical Phenomena↗
PubMed1988

Escape nightmares and postescape stressful events.

Correlation matrix based on questionnaire item responses by 38 Czechoslovak refugees suggested that "escape nightmares" (recurrent nightmares about being back in the exhomeland, wanting to or trying to re-escape to the free world) are unrelated to postescape incidence of various stressful events (e.g., illness, job difficulties, financial problems). However, refugees who reported a greater number of the stressful events also reported a somewhat higher incidence of nightmares on themes other than escape from homeland (r = .34).

Adult↗
PubMed2003

Visual image analysis by square wavelets: empirical evidence supporting a theoretical agreement between wavelet analysis and receptive field organization of visual cortical neurons.

It was proposed that the human visual system analyzes images into square wavelets. To test this view, comparisons were made between the perceived similarity-dissimilarity of alphabet letters and the wavelet analyses of those same letters. For the proposal to be considered tenable, the coefficients of the wavelet analysis of similar letters must be similar, and the coefficients of the wavelet analysis of dissimilar letters must be dissimilar. From a selection of 12 letters, four pairs of letters had been reported by Van der Heijden, Mathas, and Van den Roovaart as very similar, and four other pairs of letters dissimilar. Each of the 12 letters was separately depicted in 8 x 8 matrices, and the signal represented by each of the matrices was analyzed into square wavelets using a new and original procedure which yielded a single set of coefficients for each matrix. Correlations between sets of coefficients were high (r ranged from .88 to .58) for those letter pairs judged high in similarity; correlations were low (r ranged from -.02 to .29) for those letter pairs judged low in similarity. When the correlations between the coefficients of wavelets of all eight-letter pairs were compared with the judged similarity-dissimilarity of all eight-letter pairs, the linear agreement was statistically significant. Agreement was found between the neurophysiological mapping of receptive fields of visual cortical neurons and the vectors or the pattern of pluses and minuses which characterized the wavelet analysis. Furthermore, regeneration of the visual image, or the pattern of neural activity representing the image, could be described by a tree-like flow of information among visual cortical neurons which received response data from visual receptive fields, the response data being wavelet coefficients. Results indicate the analysis accurately produces reliable transformations of visual patterns and may be a process used by the visual system.

Algorithms↗
PubMed2002

Relation of career beliefs to career indecision among distance education adult college students in Taiwan.

This study constructed a predictive model of career indecision for adult college students participating in distance education by using a sample of 178 adult college students in Taiwan's Open University. The stepwise regression analysis of the career indecision scale, using sex, age, and 20 subscores of the Career Beliefs Checklist as predictor variables, yielded four variables (age and three major core career beliefs. Self-sufficiency, External Influences, and Self-advocacy) as significantly contributing to the reported variance in the Career Indecision score of the Career Decision Scale. A Pearson product-moment correlation matrix described the relationships between the Career Indecision score and the 20 subscores of the Career Beliefs Checklist, age, and sex. Recommendations for incorporating career beliefs into career education courses are offered.

Adult↗
PubMed2006

Re-analysis of correlations among four impulsivity scales.

Impulsivity plays a key role in normal and pathological behavior. Although there is some consensus about its conceptualization, there have been many attempts to build a multidimensional tool due to the lack of agreement in how to measure it. A recent study claimed support for a three-dimensional structure of impulsivity, however with weak empirical support. By re-analysing those data, a four-factor structure was found to describe the correlation matrix much better. The debate remains open and further research is needed to clarify the factor structure. The desirability of constructing new measures, perhaps analogously to the Wechsler Intelligence Scale, is emphasized.

Adult↗
PubMedDate not supplied

Analysis of the vestibulo-spinal system with a five-dimensional feedback model.

The role of the vestibulo-spinal system involved in the maintenance of upright standing posture was studied by a time series analysis with a 5-dimensional feedback model. The system was composed of sways of the head, shoulders, hips and activities of the nuchal and soleus muscles. The results were displayed as determinants of noise correlation matrix, power spectrum, correlogram, transfer function and relative power contribution. The five movements constitute a feedback system in normal subjects. Bilateral loss of labyrinthine function indicates a break in the feedback system. The power spectrum and relative noise contribution indicate that the vestibulo-spinal system regulates low-frequency body sway in upright standing. However, the contribution of the system was low in the overall control of standing posture.

Feedback↗
PubMed1976

Addiction to diazepam.

Literature is reviewed which raises the question of diazepam's addicting potential. To explore this issue, 50 subjects referred from medical, surgical, and psychiatric clinics were evaluated by interview regarding their use of diazepam. Replies to a standardized interview were combined with physicians' ratings of addiction under two conditions: without and then with the knowledge that the drug in question was diazepam. A computer-aided analysis of these data, including a correlation matrix, revealed surprisingly strong evidence for diazepam's capacity to elicit tolerance and withdrawal in this sample. Psychiatric patients were no more "addiction-prone" in this regard than patients given diazepam for medical conditions. Of equal significance, physicians' impressions of addiction were significantly altered toward a more favorable view when they learned that the drug in question was diazepam. Implications for psychiatric and medical practice are discussed, and suggestions for further controlled research offered.

Administration, Oral↗
PubMed2004

The interrelationship of psychosocial risk factors for coronary artery disease in a working population: do we measure distinct or overlapping psychological concepts?

There is growing evidence that psychosocial factors contribute to the risk of coronary artery disease. Commonly used psychometric scales share several features leading to questions about whether they reflect distinguishable concepts. Study participants were 822 employees of the Augsburg Cohort Study (mean age 40 years, 89% men). The authors analyzed the interrelationship between the following psychosocial measures by applying Pearson correlations and factor analysis to the Hospital Anxiety and Depression Scale (HADS), Type D Personality (DS14), the Maastricht Vital Exhaustion Questionnaire (VE), Social Support (F-SozU), the SF12 Health Survey, and Effort-Reward Imbalance. Although the full correlation matrix revealed low to medium associations supporting the notion that the applied psychometric scales show some conceptual overlap, factor analyses resulted in 13 distinguishable and interpretable factors, considerably reflecting the original psychometric scales. This strengthens the assumption that the psychometric scales used constitute distinct psychological concepts, in particular, depressive symptomatology and negative affectivity versus vital exhaustion.

Adolescent↗
PubMed1991

[A numerical taxonomic study on heterophyid trematodes].

A numerical taxonomy was studied on a group of heterophyid trematodes and analysis was made on the following species: Metagonimus yokogawai (3 OTU, Operational Taxonomic Unit), Metagonimus Miyata Type (3 OTU), Metagonimus takahashii (2 OTU), Heterophyes dispar (2 OTU), Heterophyes heterophyes (1 OTU), Heterophyes nocens (2 OTU), Heterophyopsis continua (1 OTU), Pygidiopsis summa (3 OTU), Stellantchasmus falcatus (2 OTU) and Stictodora lari (2 OTU). Twenty-six morphological characters were measured and their values were expressed as relative ratios. Similarity and correlation matrix among each individuals were calculated. Clustering analysis by Ward's method and factor analysis were performed using the SAS (Statistical Analysis System) package. As a result, the groups belonging to the genus of Metagonimus were divided into three phenons (Metagonimus yokogawai, Metagonimus Miyata Type, M. takahashii), and Metagonimus Miyata Type was classified as the level of subspecies of M. takahashii. The groups belonging to the genus Heterophyes were clearly divided into three phenons (Heterophyes dispar, H. heterophyes, H. nocens), and H. nocens was classified as not a subspecies level of H. heterophyes but a distinct species. Other species were classified as distinct phenons. From these results, the application of numerical taxonomy on trematode classification is considered to be a great aid to determine the limit of taxa.

Animals↗
PubMed1991

Multidimensional stress management in nursing education.

This study investigated the effectiveness of multidimensional stress management training for beginning baccalaureate nursing students (N = 57). An experimental pretest-posttest placebo group, control group design was used. Two pretest and three posttest measurements of the dependent variables of state anxiety (SA), reported emotions, and coping methods were completed. The program incorporated cognitive, physiological, and behavioral approaches. Second, this study examined the relationship of self-esteem, recent life experiences, and trait anxiety (TA) to encountered stressors. A repeated measures analysis of variance demonstrated no significant differences between treatment groups across time. However, written workshop evaluations demonstrated a strongly positive response by the experimental group. Significant within-subjects change was demonstrated for all 57 subjects over the semester on the dependent variables of SA, Threat emotions, and Challenge emotions reinforcing Lazarus' transactional model. A correlation matrix revealed that individuals with low self-esteem appraised the environment in a negative manner as did those subjects with high state and TA. Recommendations include further revision of the multidimensional stress management approach and continued use of the transactional theoretical framework.

Adaptation, Psychological↗
PubMed2004

[Indices of public health services and resource allocation from the Health Ministry of Chile].

BACKGROUND: Chile has a National Health Services System, formed by 29 Health Services. An efficient resource distribution among this services is crucial for an efficient health care delivery. AIM: To obtain indices from the Chilean Public Health Services, that could improve allocation of resources. MATERIAL AND METHODS: Information from the Chilean Public Health Services, corresponding to activities during 2001 budgetary period, was collected. This is the latest complete and official information for the totality of Health Services in the country. Seventeen variables generated or monitored by the Instituto Nacional de Estadísticas (INE), the Ministerio de Salud (MINSAL), the Ministerio de Hacienda, the Ministerio de Planificación y Cooperación (MIDEPLAN) and the Fondo Nacional de Salud (FONASA) were studied. The Main Components Analysis (ACP) was used, obtained from the R correlation matrix. RESULTS: The first two main components were selected, with an accumulated percentage of explained variability of 63.05%. The first component is related to the population assigned to each Health Service. This corresponds to the number of people needed to treat in the hospitals of these Services and their answer to this demand, justified by the expenses in which each Health Service incurs. There is an inverse relation of the first component with health indicators, measured by burden of disease and death. The second main component would represent the social and economic characteristics of the population, poor and very poor populations and public health insurance beneficiaries, to take care of in each Health Service. CONCLUSIONS: Health indicators in each Health Service are not considered a priority for resource distribution among Health Services in the country. The transference is done considering the indices contained in the two main components defined.

Chile↗
PubMed2005

[A proposal of new indices for hospital management].

BACKGROUND: Diagnosis related groups (DRGs) are the most reliable patient classification system in hospital management. When this information is unavailable, other reliable classification system must be used. AIM: To obtain useful indices for hospital management, based on descriptive multivariate techniques. MATERIAL AND METHODS: Data on admissions to a University Hospital during 2003 were analyzed. Number of discharges, lethality rate, re-admission rate, number of outpatient consultations, length of hospital stay and surgical complexity index were analyzed, using information obtained by the Operations Management Department. The Principal Components Analysis (PCA) technique was applied and the R correlation matrix was used. RESULTS: A total of 24,345 discharges were analyzed. The first two principal components were selected, accounting cumulatively for 76% of data variability (47% for the first and 29% for the second). CONCLUSIONS: The first component may be assimilated to a new index representing the difficulty of the attended cases, which we have termed Case Complexity. The second principal component would explain the number of attended persons, which we have termed Case Load. These two indices allow us to classify hospital services.

Chile↗
PubMed1987

[EEG changes during the performance of verbal and non-verbal tasks].

EEGs were recorded from 12 positions of the scalp (10-20 system) in 30 normal right-handed subjects. Powers of alpha component obtained from contralateral loci during their performance of verbal tasks (definition of nouns, tongue twisting) and non-verbal tasks (memorization of shapes, imagination of a face) were compared. At the frontal and occipital regions, the right hemisphere dominance of the alpha component was more distinctly demonstrated during the verbal tasks than the non-verbal tasks, while at the occipito-temporal region, the left hemisphere dominance was distinctly demonstrated during the non-verbal tasks than the verbal tasks. However, the alpha components were dominant at the left occipito-temporal region during the verbal tasks and at the right frontal and occipital regions during the non-verbal tasks. The latter result was discussed in relation to the findings of Moss, Davidson, & Saron (1985) and noise generated by apparatuses. Component analysis was carried out for a correlation matrix made by four task variables and 12 samples of electrode positions. Two factors were derived; the first factor was loaded on the verbal tasks whereas the second factor on non-verbal tasks. The factor scores of the first factor were high at the right temporal region and those of the second factor at the left temporal region. These results proved the utility of principal factor method onto general patterns of alpha component during the tasks.

Adolescent↗
PubMedDate not supplied

The Interest Checklist: a factor analysis.

OBJECTIVE: The purpose of this study was to determine whether the 80 items on the Interest Checklist empirically cluster into the five categories of interests described by Matsutsuyu, the developer of the tool. METHOD: The Interest Checklist was administered to 367 subjects classified in three subgroups: students, working adults, and retired elderly persons. An 80-item correlation matrix was formed from the responses to the Interest Checklist for each subgroup and then used in a factor analysis model to identify the underlying structure or domains of interest. RESULTS: Results indicated that the Social Recreation theoretical category was empirically independent for all three subgroups; the Physical Sports and Cultural/Educational theoretical categories were empirically independent for only the college students and working adults; and the Manual Skills theoretical category was empirically independent for only the working adults. CONCLUSION: Although therapists should continue to be cautious in their interpretation of patients' Interest Checklist scores, the tool is useful for identifying patients' interests in order to choose meaningful activities for therapy.

Activities of Daily Living↗
PubMed2026

Mapping Focal and Generalized Effects of Common Genetic Variants on Human Brain Structure.

Genome-wide association studies (GWAS) have advanced the quest to understand how specific genetic variants influence human brain structure and function. Recent work has identified hundreds of common variants associated with subcortical brain volumes, sparking interest in how these genetic markers overlap across brain networks. While this can be estimated by hierarchical clustering of the genetic correlation matrix to identify modular patterns of shared architecture, no brain-wide maps of these effects are available. To address this, we computed polygenic scores (PGS) from loci associated with ten brain volume regions of interest (ROIs): nine major subcortical structures and intracranial volume, with each locus weighted by its association with regional volume. In an independent sample from the discovery GWAS, we performed large-scale segmentation of 3D volumetric T1-weighted MRI scans using voxel-based morphometry (VBM) to map 3D profile of regions where gray matter volume (GMV) was associated with each PGS. We found statistically significant, localized effects for PGS defined for the amygdala, thalamus, and basal ganglia, but PGS for brainstem volume was associated with widespread differences throughout the brain. These brain-wide maps reveal patterns consistent with both localized and distributed genetic influences, offering a novel approach to interpret the genomic architecture of brain structure.

GWAS↗