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PubMed2006

[The unbroken power of psychiatry as seen through the eyes of Michel Foucault].

Is the psychiatrist still a powerfulforce in society? Foucault, a 'historical philosopher' concerned with power relations, would have answered this question in the affirmative. Possibly, however, the psychiatrist's sovereign power is weaker than it was a century ago because some of the psychiatrist's tasks have been re-allocated. Some have been assigned to the growing number of specialist groups in the mental health service, others have been put in the hands of 'health managers' who form part of our country's growing bureaucracy and put a financial and economic burden on our health service. Nevertheless, the procedural power of psychiatrist has not been weakened; psychiatrists are able to deprive patients of their freedom, pronounce them unfit for work and reduce punishments and sentences for serious crime on the grounds of diminished responsibility. This procedural power is accentuated by the increasing influence of psychology in society. The power of psychiatric knowledge has shifted from an archaic to a demonstrative discourse about truth which is rooted in evidence-based medicine and which enhances the power of psychiatrists still further. This may also mean that the 19th century concept of hysteria is perpetuated in psychiatric practice in all kinds of modern clinical forms.

Humans↗

PubMed1987

Motivational needs for power and spouse-specific assertiveness in assaultive and nonassaultive men.

Men who had assaulted their wives were compared to maritally conflicted (but nonassaultive) and satisfactorily married controls through the use of Thematic Apperception Test stories scored for the need for power. When the stimulus pictures showed ambiguous male-female relationships, the assaultive men generated higher need-for-power scores than the average of both control groups combined but did not differ from the maritally conflicted group on need for power. The assaultive men had lower spouse-specific assertiveness scores than either control group, however. A discriminant analysis based on need-for-power and assertiveness scores correctly classified the wife assaulters and maritally conflicted males 90% of the time. The resulting profile of assaultive men was of a group high in the need to exert power in relationships with women but lacking in the verbal resources to do so. It was hypothesized that this combination of a high need for power and a deficit in verbal ability to generate influence produces chronic frustration, which may increase the risk of violence when combined with other factors.

Adult↗

PubMedDate not supplied

Cultivating power: ten steps to success.

1. In today's decentralized organization, front line managerial competency is exemplified by the effective use of power. Managerial responsibilities require that more attention must be focused on power concepts as they pertain to Today's OR manager. 2. Acquiring power means acquiring potential influence. The OR manager, to be successful and effective, must have abilities that go beyond planning and evaluation. OR departments do not exist in a vacuum, but are part of the organizational whole. Thus, the OR manager must be able to operate within the whole hospital environment. 3. If OR managers use power wisely, it can help them achieve desired goals. Effective use of power will yield positive managerial outcomes. It will help everyone keep from being angry, frustrated, and ineffective in their roles. When used constructively, power can help OR managers actualize the potential that they and their staff members have for improving systems that affect job satisfaction and patient care.

Humans↗

PubMed1993

Reminiscence: a viable option to enhance power in elders.

The purpose of this study was to investigate the usefulness of reminiscent storytelling as a therapeutic modality to enhance the sense of power in well elders (ages 60-86). The study was conceptualized within Rogers' (1986) Science of Unitary Human Beings and focused on Barrett's theory of power. A pre- and posttest design with experimental and control groups was used with Barrett's Power as Knowing Participation in Change Test, Version II as the measure of power (personal control). Experimental group subjects were pretested and then participated in three reminiscence sessions during a 1-week period. Subjects were then posttested both at the end of the reminiscence sessions and again after a 5-week interval. Control group subjects were tested on a schedule identical to that of the experimental group, but participated in no reminiscence sessions. Although an overall significant difference (p = 0.003) in scores was found over the testing period, no differences were found between experimental and control groups. Both experimental (n = 34) and control (n = 41) groups demonstrated a small but insignificant decrease in power between the pretest and posttest 1. Both groups then experienced a significant increase in power between posttest 1 and posttest 2. It is recommended that research energies continue to be directed toward the investigation of this topic. In our contemporary high tech world which often allows minimal human contact and diminishing quality of life for the aged, novel modalities such as reminiscence offer a human to human exchange, which may hold the key to this modern-day challenge.

Aged↗

PubMed1994

Physical fitness and CHD risk factors in operators and managers of nuclear and thermal power plants situated in environmentally different regions of the Czech Republic.

Nuclear and thermal power plants are seen as one of the threats to human health. Most investigations explore the potential hazards of radiation and the potential impact of a polluted environment. Less attention is being paid to the human factor, i.e. to the people who actually are directly involved in the generation of electrical power and whose sudden collapse could result in a disaster. In this paper dealing with the prevention of CHD we submit, in a condensed form, the results of our long-term testing of operators and managers from one nuclear and two thermal power plants, located in totally dissimilar regions of the Czech Republic. In our investigations, which are still going on, we are using a whole battery of methods--case history, anthropological, clinical and functional tests. Our test subjects are middle-aged men, an age group most prone to CHD. The most favourable results of the vast majority of tests were obtained at the nuclear power plant in southern Moravia, while the most adverse ones--with respect to the danger of CHD--in the men from the thermal power plant in Prague. For the most part these results, in the light of a thorough analysis of the case history, anthropological, clinical, functional and biochemical investigations of these middle-aged men, should be seen as the cumulative effect of both their way of life (locomotor activities, nutrition) and the environment, in which they live. The men working at the nuclear power plant live in the least polluted environment. People's way of life may to some extent be influenced and some preventive steps along these lines have already been taken.

Adult↗

PubMed1992

Anaerobic endurance and peak muscle power in children with spastic cerebral palsy.

The aim of this study was to provide information on anaerobic muscle endurance (mean power) and peak muscle power in children with spastic cerebral palsy. We measured peak power and mean power of the upper and lower limbs in 29 boys and 20 girls, aged from 6 to 14 years, by means of the Wingate Anaerobic Test. In addition, the physical components (physical capacity, upper limb, and lower limb) of a system used for evaluating function in the physically disabled were assessed. Of the 49 subjects, 46 and 37 successfully completed the arm and leg Wingate Anaerobic Test, respectively. Compared with norms for age and gender (healthy, nonathletic children), peak and mean power in the patients, even when corrected for body weight, were distinctly subnormal. The performance of subjects with quadriplegia was 3 to 4 SDs below the mean for controls. Twenty-five of diplegic and hemiplegic subjects had values below 2 SDs. When the data were analyzed according to the severity of the cerebral palsy, with the use of the physical capacity, upper limb, and lower limb score, those children with moderate to severe cerebral palsy had values for mean and peak power of the arm and leg 3 to 4 SDs below the normal mean. Values for children with only mild cerebral palsy also fell below the mean, but the data were more scattered, especially for the leg. The lower muscle performance may reflect both quantitative and qualitative differences in the upper- and lower-limb muscles, due to altered innervation and, in the more severely affected children, disuse.

Adolescent↗

PubMed2000

Potential gain in efficiency and power to detect gene-environment interactions by matching in case-control studies.

BACKGROUND: There is growing interest in interactions between genetic and environmental risk factors of disease, but adequate power to detect such interactions in epidemiologic studies is of concern. The aim of this paper is to quantify the effect of matching on the efficiency of estimation and power to detect gene-environment interactions in case-control studies. METHODS: Starting from an empirical example in cancer epidemiology, we simulated frequency matched and unmatched case-control studies for a wide range of assumptions regarding the prevalence and the effects of an environmental and a genetic factor on disease risk as well as the quality and quantity of the interaction between these factors. Simulated studies were analyzed with multivariable logistic regression. RESULTS: Matching increased the efficiency and power in most scenarios. The gain was most pronounced in scenarios assuming a low prevalence of the environmental exposure. In such scenarios, equivalent power was only obtained with more than twice as many unmatched than matched controls. CONCLUSIONS: Frequency matching for known environmental risk factors with a low prevalence in the population may increase the efficiency of estimation and power of case-control studies to detect gene-environment interactions considerably. Investigators should weigh the gain in efficiency and power against known potential disadvantages of matching.

Case-Control Studies↗

PubMed1997

Study of magnetic fields from power-frequency current on water lines.

The magnetic fields from power-frequency current flowing on water lines were investigated in a new approach that involved an area-wide survey in a small town. Magnetic fields were measured outside the residence under power cables and over water lines, and each residence was characterized as to whether it received water from a private well or the municipal water system. The magnetic field data revealed two statistical modes when they were related to water supply type. The data also showed that in the case of the high mode, the magnetic field remained constant along the line formed by power drop wires, at the back of the house, and the water hookup service, in front of the house, all the way to the street. The patterns are explained by the coincidence of measurement points and the presence of net current flowing on power mains, power drop conductors, residential plumbing, water service hookups, and water mains. These patterns, together with other characteristics of this magnetic field source, such as the gradual spatial fall-off of this field and the presence of a constant component in the time sequence, portray a magnetic field more uniform and constant in the residential environment than has been thought to exist. Such characteristics make up for the weakness of the source and make net current a significant source of exposure in the lives of individuals around the house, when human exposure to magnetic fields is assumed to be a cumulative effect over time. This, together with the bimodal statistical distribution of the residential magnetic field (related to water supply type), presents opportunities for retrospective epidemiological analysis. Water line type and its ability to conduct power-frequency current can be used as the historical marker for a bimodal exposure inference, as Wertheimer et al. have shown.

Data Collection↗

PubMed2001

Power comparisons between the TDT and two likelihood-based methods.

We compare the statistical power of the transmission disequilibrium test (TDT) with that of two likelihood-based linkage tests, the classical LOD score and a modified LOD score in which a linkage disequilibrium (LD) parameter is incorporated into the likelihood (LD-LOD). We hypothesize that, when LD is present, the LD-LOD will have the greatest power of the three tests because the TDT breaks a multiplex pedigree into triads, and the LOD score has previously been shown to have lower power when LD is present but not accounted for. We test this hypothesis using a simulation study in which we generate affected sib-pair (ASP) pedigrees under a range of genetic models, varying the genotypic relative risk (GRR) from 6 to 16. Because the likelihood-based tests require that a genetic model be specified, we compare the tests under two scenarios. First, we assume the true genetic model in the analysis, and second, we compare the tests when the LD-LOD (LOD) is maximized over two wrong genetic models. For the generating models we considered, we find that the LD-LOD has greater power than the TDT even when the genetic models is mis-specified and the results corrected for multiple tests. Extreme differences occur under the multiplicative and dominant models, for which the difference in power is as high as 40% at complete LD. The LOD score provides the lowest power in the presence of LD for the range of GRR considered here.

Adult↗

PubMed2003

Manual versus powered toothbrushing for oral health.

BACKGROUND: Specific oral bacteria, generically known as "dental plaque" are the primary cause of gingivitis (gum disease) and caries. The removal of dental plaque is thought to play a key role in the maintenance of oral health. There is conflicting evidence for the relative merits of manual and powered toothbrushing in achieving this. OBJECTIVES: To compare manual and powered toothbrushes in relation to the removal of plaque, the health of the gingivae, staining and calculus, dependability, adverse effects and cost. SEARCH STRATEGY: We searched the Cochrane Oral Health Group's Trials Register (to 22/8/02); Cochrane Central Register of Controlled Trials (The Cochrane Library Issue 3, 2002); MEDLINE (January 1966 to week 5 2002); EMBASE (January 1980 to week 3 July 2002) and CINAHL (January 1982 to June 2002). Manufacturers of powered toothbrushes were contacted for additional published and unpublished trials. SELECTION CRITERIA: Trials were selected if they met the following criteria: design-random allocation of participants; participants-general public with uncompromised manual dexterity; intervention- supervised manual and powered toothbrushing for at least four weeks; primary outcomes-the change in plaque and gingivitis over that period. DATA COLLECTION AND ANALYSIS: Six reviewers independently extracted information in duplicate. Indices for plaque and gingivitis were expressed as standardised values for each study. The effect measure for each meta-analysis was the standardised mean difference (SMD) with the appropriate 95% confidence intervals (CI) using random effect models. Potential sources of heterogeneity were examined, along with sensitivity analyses for the items assessed for quality and publication bias. MAIN RESULTS: Twenty-nine trials, involving 2,547 participants, provided data for the meta-analysis. Brushes that worked with a rotation oscillation action removed more plaque and reduced gingivitis more effectively than manual brushes in the short and long term. For plaque at one to three months the SMD was -0.44 (95% CI: -0.66 to -0.21), for gingivitis SMD -0.44 (95% CI: -0.72, -0.15). These represented an 11% reduction on the Quigley Hein plaque index and a 6% reduction on the Löe and Silness gingival index. At over three months the effects were SMD for plaque -1.15 (95% CI: -2.02,-0.29) and SMD for gingivitis -0.51 (95% CI: -0.76, -0.25). These represented a 7% reduction on the Quigley Hein Plaque Index and a 17% reduction on the Ainamo Bay Bleeding on Probing Gingival Index. The heterogeneity found in these meta-analyses for short term trials was caused by one trial that had exceptionally low standard deviations. Sensitivity analyses revealed the results to be robust when selecting trials of high quality. There was no evidence of any publication bias. No other powered brush designs were consistently superior to manual toothbrushes. In these trials, data on cost, reliability and side effects were inconsistently reported. Those side effects that were reported on in the trials were localised and temporary. REVIEWER'S CONCLUSIONS: Powered toothbrushes with a rotation oscillation action achieve a modest reduction in plaque and gingivitis compared to manual toothbrushing. Observation of methodological guidelines and greater standardisation of design would benefit both future trials and meta-analyses.

Dental Devices, Home Care↗

PubMed1992

Evolution of the power ("squeeze") grip and its morphological correlates in hominids.

The "squeeze" form of power grip is investigated for the purposes of clarifying the hand posture and activities associated with the grip, assessing the potential in chimpanzees for using the grip, and identifying morphological correlates of an effective power grip that may be recognized in fossil hominid species. Our approaches include: (1) the analysis of the human grip, focusing on both the hand posture involved and hand movements associated with use of the grip in hammering; (2) the analysis of similar chimpanzee grips and associated movements; (3) comparative functional analysis of regions in the hand exploited and stressed by the grip and its associated movements in humans; and (4) a review of the literature on the power grip and its morphological correlates. Results of the study indicate that humans use a squeeze form of power grip effectively to wield cylindrical tools forcefully as extensions of the forearm. Several morphological features occur in high frequency among humans which facilitate the grip and are consistent with the large internal and external forces associated with it in hammering and in other tool-using activities. Chimpanzee hand postures resembling this form of human power grip are not fully comparable and lack some of these morphological correlates that facilitate its use. The hand of Australopithecus afarensis does not appear to have been stressed by use of the grip, but there is some evidence for this type of stress in the metacarpals from Sterkfontein Member 4. Hands from Olduvai and Swartkrans do not provide sufficient evidence for assessment of power grip capabilities.

Adult↗

PubMed1987

Simple method to measure power density entering a plane biological sample at millimeter wavelengths.

A simple method for measuring microwave power density is described. It is applicable to situations where exposure of samples in the near field of a horn is necessary. A transmitted power method is used to calibrate the power density entering the surface of the sample. Once the calibration is available, the power density is known in terms of the incident and reflected powers within the waveguide. The calibration has been carried out for liquid samples in a quartz cell. Formulas for calculating specific absorption rate (SAR) are derived in terms of the power density and the complex dielectric constant of the sample. An error analysis is also given.

Calibration↗

PubMed1994

Rhesus monkey behavior during exposure to high-peak-power 5.62-GHz microwave pulses.

Limits on the exposure to high-peak-power, short-duration microwave pulses have only recently been adopted. Additional data, however, are needed to understand the effects that may be produced by exposure to high-peak-power pulsed microwaves. Four male rhesus monkeys (Macaca mulatta) were trained on an operant task for food pellet reward to investigate the behavioral effects of very high-peak-power 5.62 GHz microwaves. The operant task required monkeys to pull one plastic lever on a variable interval schedule (VI-25 s) and then respond to color signals and pull a second lever to obtain food. The monkeys were conditioned to perform a color discrimination task using one of three colors displayed by a fiber-optic cable. A red signal was the discriminative stimulus for responding on the first lever. A response on the second lever when a green signal was presented (1 s duration) delivered a food pellet. If a response on the second lever was made in the presence of a white signal, a 30-s timeout occurred. While performing the behavioral task, the monkeys were exposed to microwave pulses produced by either a military radar (FPS-26A) operating at 5.62 GHz or the same radar coupled to a Stanford linear energy doubler (SLED) pulse-forming device (ITT-2972) that enhanced peak power by a factor of nine by adding a high power pulse to the radar pulse. The effects of both types of pulses were compared to sham exposure. Peak field power densities tested were 518, 1270, and 2520 W/cm2 for SLED pulses and 56, 128, and 277 W/cm2 for the radar pulses. The microwave pulses (radar or SLED) were delivered at 100 pps (2.8 microseconds radar pulse duration; approximately 50 ns SLED pulse duration) for 20 min and produced averaged whole-body SARs of 2, 4, or 6 W/kg. Compared to sham exposures, significant alterations of lever responding, reaction time, and earned food pellets occurred during microwave exposure at 4 and 6 W/kg but not at 2 W/kg. There were no differences between radar or SLED pulses in producing behavioral effects.

Analysis of Variance↗

PubMed1984

Dendritic caliber and the 3/2 power relationship of dentate granule cells.

A quantitative examination of granule cell dendritic caliber and knowledge of dendritic lengths allows assessment of the distribution of dendritic membrane and the 3/2 power relationship at branch points. This paper presents caliber data of Golgi-impregnated rat dentate gyrus. We used camera lucida drawings of the dendritic trees of 15 dorsal leaf and 15 ventral leaf granule cells to quantify mean dendritic caliber, dendritic taper, the 3/2 power relationship of parent and sibling dendritic diameters at branch points, and surface area. First-order dendrites vary substantially in diameter. However, the mean caliber of all other dendrites is uniform across the proximal two-thirds of the molecular layer for the dorsal and ventral leaves. The average diameter here is 1 micron. More distally, only mean ventral leaf dendritic caliber declines. Granule cell dendritic taper is due primarily to caliber decreases at branch points and not to a gradual decline in diameter across the length of a dendritic segment. Comparing the parent segment diameter raised to the 3/2 power with the sum of the 3/2 powers of the two sibling segment diameters reveals, for the dendritic tree located within the distal two-thirds of the molecular layer, the desired 3/2 power relationship for the dorsal and ventral leaves. More proximally, where first-, second-, and third-order dendrites branch sequentially across a 60-100-micron extent, a 3/2 power relationship is not obtained. For the average dorsal leaf granule cell, dendritic surface area (without spines) is 11,984 micron2. The ratio of dendritic to somatic surface area is 28:1. Discussion of these data includes their implications for electrotonic modeling of the dentate granule cell.

Animals↗

PubMed2001

Deficits in haptic perception and right parietal theta power changes in patients with anorexia nervosa before and after weight gain.

OBJECTIVE: Our goal was to investigate whether patients with anorexia nervosa (AN) show deficits in haptic exploration tasks before and after weight gain. METHOD: The haptic exploration tasks consisted of palpating the structure of six sunken reliefs in sequence with both hands, eyes closed. After each exploration, the structure was reproduced on a piece of paper. A 19-channel digital electroencephalogram (EEG; linked ears) was continuously recorded during rest and haptic tasks for 10 AN patients (females, mean age: 15.90) and 10 healthy controls (CO; females, mean age: 16.14). Mean spectral power density was calculated as the mean amplitude of the spectral lines of the theta band (4-8 Hz). The AN patients were examined again after weight gain (T(0) and T(1)). RESULTS: The reproductions submitted by the AN patients were of notably poorer quality than those of the CO. Reproduction quality was unchanged after weight gain and independent of body mass index and intelligence. Mean exploration time was similiar in AN patients and CO. The analysis of spectral EEG power of both groups showed significant decrease in power data in the theta frequency band during haptic exploration compared with the rest intervals. The comparison of the theta power between CO and AN patients during haptic exploration showed major differences between the groups in both T(0) and T(1). Theta power was lower in AN patients than in the CO over the right hemisphere and right parietal regions. DISCUSSION: The quality of reproduction of the haptic stimuli and the theta-power changes indicate a cortical dysfunction and deficits in somatosensory integration processing of the right parietal cortex in AN patients even after weight gain.

Adolescent↗

PubMed2003

Power of multifactor dimensionality reduction for detecting gene-gene interactions in the presence of genotyping error, missing data, phenocopy, and genetic heterogeneity.

The identification and characterization of genes that influence the risk of common, complex multifactorial diseases, primarily through interactions with other genes and other environmental factors, remains a statistical and computational challenge in genetic epidemiology. This challenge is partly due to the limitations of parametric statistical methods for detecting genetic effects that are dependent solely or partially on interactions with other genes and environmental exposures. We previously introduced multifactor dimensionality reduction (MDR) as a method for reducing the dimensionality of multilocus genotype information to improve the identification of polymorphism combinations associated with disease risk. The MDR approach is nonparametric (i.e., no hypothesis about the value of a statistical parameter is made), is model-free (i.e., assumes no particular inheritance model), and is directly applicable to case-control and discordant sib-pair study designs. Both empirical and theoretical studies suggest that MDR has excellent power for identifying high-order gene-gene interactions. However, the power of MDR for identifying gene-gene interactions in the presence of common sources of noise is not currently known. The goal of this study was to evaluate the power of MDR for identifying gene-gene interactions in the presence of noise due to genotyping error, missing data, phenocopy, and genetic or locus heterogeneity. Using simulated data, we show that MDR has high power to identify gene-gene interactions in the presence of 5% genotyping error, 5% missing data, or a combination of both. However, MDR has reduced power for some models in the presence of 50% phenocopy, and very limited power in the presence of 50% genetic heterogeneity. Extending MDR to address genetic heterogeneity should be a priority for the continued methodological development of this new approach.

Algorithms↗

PubMed2003

Does accounting for gene-environment (GxE) interaction increase the power to detect the effect of a gene in a multifactorial disease?

Despite tremendous efforts, few genes involved in the susceptibility for complex disorders have been identified. One explanation is that these disorders are a result of an interaction between genes and environment, and under such conditions, it may be difficult to measure the true genetic effect without accounting for the interaction. Umbach and Weinberg ([2000] Am. J. Hum. Genet. 66:251-261) proposed an association test which looks at the joint effects of genotype and environment, using case-parent trios. In this study, we explore under which conditions accounting for GxE interaction enhances one's ability to detect the role of genetic factors in complex diseases. Using asymptotic power calculations, we investigate the power to detect the gene effect over varying exposure frequencies and different scenarios of GxE interaction. We show that for a given sample size, interaction scenario, and allele frequency, the actual gain in power while accounting for the interaction depends on the magnitude of the exposure frequency: the largest gains are seen for relatively low exposure frequencies. Moreover, a loss of power can be observed when the exposure is frequent and/or the exposure effect is strong. If we consider a gene with a disease allele frequency of 0.2, with no effect in the absence of exposure, an exposure with a 10-fold increase risk and a GxE relative risk of 2, then when the exposure frequency is 0.1, accounting for GxE interaction increases the power to detect the gene effect in 200 trios by 10%; alternatively, when the exposure frequency is 0.9, it decreases the power by 15%.

Alleles↗

PubMed2006

Improving the power of association tests for quantitative traits in family studies.

Association mapping based on family studies can identify genes that influence complex human traits while providing protection against population stratification. Because no gene is likely to have a very large effect on a complex trait, most family studies have limited power. Among the commonly used family-based tests of association for quantitative traits, the quantitative transmission-disequilibrium tests (QTDT) based on the variance-components model is the most flexible and most powerful. This method assumes that the trait values are normally distributed. Departures from normality can inflate the type I error and reduce the power. Although the family-based association tests (FBAT) and pedigree disequilibrium tests (PDT) do not require normal traits, nonnormality can also result in loss of power. In many cases, approximate normality can be achieved by transforming the trait values. However, the true transformation is unknown, and incorrect transformations may compromise the type I error and power. We propose a novel class of association tests for arbitrarily distributed quantitative traits by allowing the true transformation function to be completely unspecified and empirically estimated from the data. Extensive simulation studies showed that the new methods provide accurate control of the type I error and can be substantially more powerful than the existing methods. We applied the new methods to the Collaborative Study on the Genetics of Alcoholism and discovered significant association of single nucleotide polymorphisms (SNP) tsc0022400 on chromosome 7 with the quantitative electrophysiological phenotype TTTH1, which was not detected by any existing methods. We have implemented the new methods in a freely available computer program.

Alcoholism↗