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At least 91 records · Page 5Linked to original sources

The power gap: freedom, power and mental illness.

Up to one in four individuals in the US meet the diagnostic criteria for a mental illness in any given year and a significant proportion have severe or recurring illnesses (e.g. schizophrenia). Despite this prevalence, mental health services remain poorly funded, mental illness remains misunderstood and individuals with recurring illness are constrained to live lives characterized by isolation, under-employment, stigma and denial of rights. Here I examine the idea that this situation is attributable, at least in part, to the ways in which the freedom and power of the mentally ill are undermined by a range of factors, including: (i) dispersion of political power amongst interest groups, which, combined with the relatively wide distribution of the 'interest' of mental illness, has the paradoxical result that mental health interest groups do not command political power proportional to the number affected; (ii) systematic exclusion of the mentally ill from full participation in civic, social and political life (structural violence), resulting in a lack of emphasis on mental health on political agendas and the exclusion of certain policy options as possible responses and (iii) difficulties the mentally ill may experience recognizing or articulating their own needs the absence of effective health-care systems, and the absence of knowledge about alternative systems. I argue that the enhancement of individual agency is central to efforts to address this power gap, including: (i) rights-based approaches, involving the enhancement of national mental health legislation, improvement of advocacy, empowerment and guardianship processes and development of governance, accountability and quality procedures in mental health services; (ii) approaches based on enhancing direct political participation, including voter-registration programmes and development of larger, more effective interest groups and (iii) additional approaches, including increasing accountability throughout services, recognizing the effects of socio-political change on the context of care and adapting the concept of 'soft power' to strengthen advocacy programmes.

Attitude to Health↗

Power and the creation of patronizing environments: the stereotype-based behaviors of the powerful and their effects on female performance in masculine domains.

This work tested the following hypothesis: When powerful men stereotype their female subordinates in masculine domains, they behave in patronizing ways that affect the performance of their subordinates. Experiment 1 examined the stereotyping tendencies and patronizing behaviors of the powerful. Findings revealed that powerful men who stereotyped their female subordinates (i.e., those who were weakness focused) gave female subordinates few valued resources but much praise. In Experiment 2, low-power participants received resources (valued or devalued positions) and praise (high or low) from a powerful man. Subordinates who were assigned to a devalued position but received high praise (i.e., the patronizing behavior mirrored from Experiment 1) were angry. However, men performed better in the anger-inspiring situation, whereas women performed worse.

Anger↗

Does elevated power lead to approach and reduced power to inhibition? Comment on Keltner, Gruenfeld, and Anderson (2003).

D. Keltner, D. H. Gruenfeld, and C. Anderson (see record 2003-00307-004) stated a set of propositions postulating independent effects for elevated power and reduced power. The present commentary argues that past studies have permitted examining the opposite effects but not the specific effects of high and low power. Suggestions are made for improving designs and formulating analytic strategies that would permit evaluating the specific assertions that elevated power increases approach and reduced power increases inhibition.

Hierarchy, Social↗

Power consumption in shaking flasks on rotary shaking machines: II. Nondimensional description of specific power consumption and flow regimes in unbaffled flasks at elevated liquid viscosity.

This article is the second part of a series presenting and modeling the hydrodynamics and specific power consumption in shaking flasks on rotary (orbital) shaking machines. In part I, a new method was introduced that enables the accurate determination of the specific power consumption in shaking flasks. The method was first applied to investigate unbaffled flasks with a nominal volume of < or =1 L at low viscosity. In part II, the results for the specific power consumption of unbaffled shaking flasks at elevated viscosities are investigated after varying shaking frequency, flask size, filling volume, and shaking diameter. The theory introduced in part I is extended to liquids of elevated viscosities using nondimensional equations. With these results, the specific power consumption in unbaffled shaking flasks can now be fully described. For the first time, the phenomenon of the liquid being "out of phase" is observed and described. This occurs at certain operating conditions and is characterized by an increasing amount of liquid not following the movement of the shaking table, thus reducing the specific power consumption. This, of course, has much relevance for practical work with microbial cultures. The phenomenon of being "out-of-phase" is described in the form of a newly defined nondimensional phase number (Ph) in analogy to a partially filled, rotating horizontal drum. The Ph can be used to determine reasonable operating conditions for shaking flask experiments when using viscous media, avoiding unfavorable "out-of-phase" operation.

Biotechnology↗

The experience of power: examining the effects of power on approach and inhibition tendencies.

Two studies of task-focused dyads tested the approach/inhibition theory of power (D. Keltner, D. H. Gruenfeld, & C. Anderson, in press), which posits that having power increases the tendency to approach and decreases the tendency to inhibit. Results provided preliminary support for the theory: Participants higher in personality dominance or assigned control over resources expressed their true attitudes, experienced more positive and less negative emotion, were more likely to perceive rewards (i.e., that their partner liked them), and were less likely to perceive threats (e.g., that their partner felt anger toward them). Most of these effects were mediated by the sense of power, suggesting that subjective feelings of power are an important component in the effects of power.

Adult↗

Accurate intraocular lens power calculation after myopic laser in situ keratomileusis, bypassing corneal power.

PURPOSE: To describe a novel method for calculating intraocular lens (IOL) power after myopic laser in situ keratomileusis (LASIK) without using the inaccuracies of the post-LASIK corneal power. SETTING: Department of Ophthalmology, Wake Forest University Eye Center, Wake Forest University School of Medicine, Winston Salem, North Carolina, USA. METHODS: This retrospective chart review comprised 9 eyes of 9 patients who had phacoemulsification after LASIK using our method for IOL calculation. This new method assumes the patient never had myopic LASIK to calculate IOL power and then targets the IOL at the pre-LASIK amount of myopia. The pre-LASIK keratometry values, pre-LASIK manifest refraction, and the current axial length are placed in the Holladay formula, bypassing the post-LASIK corneal power. In theory, assuming that the patient had satisfactory LASIK results, the correct IOL can then be determined. RESULTS: The mean spherical equivalent postoperative refraction was +0.03 diopter (D) +/- 0.42 (SD) (range -0.625 to +0.75 D). In all 9 eyes, our method consistently chose the most accurate and precise IOL compared with other methods. CONCLUSIONS: The new method of calculating IOL power after LASIK provided excellent results and the most accurate and precise results to date.

Adult↗

Correcting the corneal power measurements for intraocular lens power calculations after myopic laser in situ keratomileusis.

PURPOSE: To describe and evaluate a refraction-derived method and a clinically derived method to calculate the correct corneal power for intraocular lens (IOL) power calculations after laser in situ keratomileusis (LASIK) and to compare the results to the commonly used history-derived method. DESIGN: Interventional case series. METHODS: Retrospective analysis of consecutive cases from clinical practice. Two hundred randomly selected eyes from 200 patients were evaluated before and after LASIK surgery. For each patient, we established the pre-LASIK and post-LASIK spectacle refraction, the pre-LASIK (Kpre) and post-LASIK K readings (Kpost). We then calculated for each case the pre- and post-LASIK refraction at the corneal plane and the amount of correction obtained by the refractive surgery (CRc). The cases were divided into two groups. Group I was used to derive the two formulas. The K values were calculated using the history-derived method (Kc.hd) in which Kc.hd = Kpre - CRc. Kc.hd was compared with Kpost. The average difference was 0.23 diopters for every diopter of myopia corrected. This value was used to calculate the corneal power using the refraction-derived method (Kc.rd) where Kc.rd = Kpost -0.23CRc. A regression equation was used to develop a clinically derived method (Kc.cd) where Kc.cd = 1.14Kpost -6.8. The values obtained with the two methods were compared with the Kc.hd values in group II to validate the results. RESULTS: Both Kc.rd and Kc.cd values correlated highly with Kc.hd when plotted on a scattergram (P <.001), and there was no statistically significant difference between the mean keratometric values (P >.5). CONCLUSIONS: The corneal power measurements for intraocular lens power calculations after LASIK need to be corrected to avoid hypermetropia after cataract surgery by either the history-derived method, the refraction-derived method, or the clinically derived method.

Adult↗

Effects of external light loading in power-type strength training on muscle power of the lower extremities in middle-aged subjects.

The purpose of this study was to evaluate and compare the effects of training either with a light load or without any load in a 16-week power-type strength training intervention in sedentary middle-aged subjects. A total of 85 subjects participated in the study. In a supervised 22-week training intervention, including 16 weeks of power-type strength training, 42 subjects (Light Load group=LL group) trained with a 1.1 kg weight on each ankle and 43 subjects (No Load group=NOL group) trained without any external load. Subjects were comparable concerning their training attendance, and anthropometric and physiological characteristics. Training effects were evaluated by measuring Vertical Squat Jump (VSJ), 20-metre Running Time (20 mRT), Maximal Anaerobic Cycling Power of leg muscles (MACP), and Maximal Oxygen Uptake (V.O (2 max)) before and after the intervention. The LL group improved VSJ and MACP significantly (p<0.05), compared with the NOL group. No difference between the groups was observed in 20 mRT or in V.O (2 max). To conclude, the external loads of 2.2 kg, in total, increased the efficiency of power-type strength training in vertical jumps and in anaerobic power in leg muscles, but not in sprint running.

Adult↗

Effect of individual time to peak power output on the expression of peak power output in the 30-s Wingate Anaerobic Test.

The objective of the present investigation was to examine a proposal which stated that individual power values should be aligned according to peak power output (PPO) before calculating the mean value of PPO. This procedure removes the variation in time it takes for individuals to reach PPO. Participants were forty-one University Rugby Union Football players of mean age 21.7 +/- 2.6 years, height 181.4 +/- 6.9 cm and body mass 88.9 +/- 12.7 kg. Data were collected using a friction-belt cycle ergometer (Monark 864, Varberg, Sweden). A significantly larger mean value for PPO was found when results were calculated from time-aligned rather than cross-sectional data (1154 +/- 246 vs. 1121 +/- 254 W, p < 0.0001); the mean difference was approximately 3 %. Additionally, the average profile of the power output curve was more reflective of individual power curves. The negative correlation between PPO and the time taken to reach PPO was - 0.32 (p < 0.05), confirming the view that the earlier the time taken to reach PPO the larger the PPO. It was concluded that the mean value of PPO and the corresponding profile for power output curves are best represented by the analysis of time-aligned rather than cross-sectional data.

Adult↗

Power calculation in matched case-referent studies. Application and accuracy of the asymptotic power function.

Although the asymptotic power function for matched case-referent (case-control) studies has been given, it is not widely applied. One reason for this is that the parameters in the power function do not correspond directly to the usual description of the research situation. When designing a matched case-referent study, the potentially available relevant information concerns the joint distribution of the determinant and matching variate, and the illness rate in relation to those factors, in the study base. Application of the asymptotic power function using these inputs is described. The asymptotic power function is then assessed by use of the Monte Carlo method and is found to be accurate. An example of the application of the asymptotic power function is given.

Epidemiologic Methods↗

Isometric strength, sprint power, and aerobic power in individuals with a spinal cord injury.

This study investigated in rather specific wheelchair tests the relationships among estimates of isometric upper-body strength (Fiso), sprint power (P30), aerobic power (VO2peak), and maximal power output (POaer) in a group of 44 men (age 34 +/- 12 yr) with longstanding spinal cord injuries ranging from C4/C5 to L5. Fiso was defined as the maximum force that could be exerted on the blocked rims of a stationary wheelchair ergometer. The estimation of P30 involved the measurement of the mean power during a 30-s all-out sprint test on the same wheelchair ergometer. VO2peak and POaer were determined as the peak oxygen uptake and highest sustained power output during a discontinuous progressive maximal exercise test on a motorized treadmill, while subjects used their own daily use wheelchair. Fiso ranged from 1.5 N.kg-1 (mean of both arms) in the group with quadriplegia to 3.4 N.kg-1 in the group with lowest-lesions, and P30 ranged from 0.5 to 1.5 W.kg-1 among the subjects. VO2peak ranged from 13.6 ml.kg-1.min-1 in the group with quadriplegia to 31.3 ml.kg-1.min-1 in the group with lowest-lesions, and POaer ranged from 0.4 to 1.1 W.kg-1. Strong positive relationships (r = 0.81-0.92) were demonstrated among all variables. Regression equations among variables were calculated: P30 = 0.51 Fiso - 0.18 (R2 = 0.75); POaer = 0.34 Fiso - 0.02 (R2 = 0.66); POaer = 0.67 P30 + 0.11 (R2 = 0.81); VO2peak = 6.52 Fiso + 4.15 (R2 = 0.76); VO2peak = 12.03 P30 + 7.43 (R2 = 0.77); VO2peak = 16.81 POaer + 6.44 (R2 = 0.84).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

EEG alpha power and alpha power asymmetry in sleep and wakefulness.

Asymmetry of waking electroencephalography (EEG) alpha power in frontal regions has been correlated with waking emotional reactivity and the emotional content of dream reports. Little is known regarding alpha asymmetry during sleep. The present study was performed to compare alpha power and alpha power asymmetry in various brain regions across states of sleep and wakefulness. Waking and sleep EEG were recorded in a group of patients undergoing polysomnographic evaluation for possible sleep disorders. Alpha EEG asymmetry in frontal and temporal regions was significantly correlated in waking versus sleep, particularly during rapid eye movement (REM) sleep. These results suggest that patterns of frontal alpha asymmetry are stable across sleep and waking and may be related to emotional reactivity during dreaming. During sleep, alpha power was highest during slow-wave sleep and lowest during REM sleep. Implications of these data for understanding the functional significance of alpha power during waking and sleeping are considered.

Adult↗

Further safety enhancement of a specialized power assisted tricycle for a child with osteogenesis imperfecta type III and design of an adjustble hand power tricycle.

Several tricycles, one a customized power assisted tricycle, and the second a hand powered tricycle were developed, which offered a unique opportunity to serve multiple purposes in several children's development throughout Wyoming. In Both cases these tricycles provide the children with the opportunity to gain muscle mass, strength, coordination, and confidence. The power assisted tricycle was completed as a senior design project in 2002, and over time safety enhancements have been completed to make the tricycle safer for operation. Unfortunately, the safety system enhancements were not acceptable for it to be released for use. For this reason the tricycle was further redesigned to include more redundant safety systems which will allow the tricycle to be safe for the child's use. The second tricycle was designed to allow for a group of children who have limited use of their legs, to be able to use the same tricycle to give them more upper body strength. A gear system using multiple gear sprockets was adapted to a preexisting tricycle to provide hand power rather than foot power. Without these improvements, the children would not have the opportunity to use these tricycles to help with their development.

Bicycling↗

[A power spectral analysis of the EEG in the newborns. II. The power spectral changes of the infants with neonatal asphyxia].

Power spectral analysis of the EEG at the neonatal period was performed in 33 babies with an Apgar score of 6 or less 1 minute after delivery. Their gestational ages ranged from 27 to 40 weeks, and birth weight from 1,013 g to 4,416 g. They were followed up until 18 months of age. All EEGs were recorded when the babies reached to 37-41 weeks of conceptional age, and analyzed using fast Fourier transformation. The percent power in active sleep was evaluated in this study. The abnormal EEG patterns in infants with neurological damage was classified into the following groups: (1) Increase of the percent power of the delta 1 band, (2) Decrease of the percent of the power of the delta 1. On the other hand, the EEG patterns at the neonatal period in infants with normal development who suffered from neonatal asphyxia were similar to those of age-matched controls. These results suggest one of the most important factors deciding the prognosis of the brain damage is the presence of a normal percent pattern. In conclusion, power spectral analysis of EEG at the neonatal period is useful in predicting the outcome of brain damage if it is used with visual inspection.

Asphyxia Neonatorum↗

Power consumption in shaking flasks on rotary shaking machines: I. Power consumption measurement in unbaffled flasks at low liquid viscosity.

In this first article of a series a new method is introduced that enables the accurate determination of the power consumption in a shaking flask. The method is based on torque measurements in the drive and appropriate compensation of the friction losses. The results for unbaffled shaking flasks at low viscosities are presented after varying shaking frequency, flask size, filling volume, shaking diameter, and surface quality (hydrophilic and hydrophobic) of the inner flask walls. The order of magnitude of the values of power consumption in shaking flasks is equal to, or even higher than, the values typical for agitated tank bioreactors. A physically based model equation for shaking flasks is derived that introduces a modified power number and a resulting constant as the only fitting parameter. With this equation, the measured results are correlated with sufficient accuracy. For the first time, comprehensive data for the power consumption in unbaffled shaking flasks at low viscosity is available, giving a detailed picture of the influences of the different variables.

Biotechnology↗

Hybrid-powered wheelchair: a combination of arm force and electrical power for propelling a wheelchair.

Many of the handicapped who could use a hand-driven wheelchair do not have sufficient arm force, arm movement and/or endurance for proper propulsion. Furthermore, there are users of electric wheelchairs who still have some arm functions and strength. In some cases a hand-driven chair, which can be propelled with reduced arm power, could be a better solution. By means of simulation, a study has been carried out to investigate the possibility of propelling a wheelchair by means of hybrid powering. Hybrid powering can be defined as a combination of arm force and electrical power. Using this hybrid principle, the necessary arm force can be decreased.

Arm↗

Evaluation of cervical lymph node vascularity: a comparison of colour Doppler, power Doppler and 3-D power Doppler sonography.

This study was undertaken to compare the performance of colour Doppler (CDS), power Doppler (PDS) and 3-D power Doppler sonography (3-D PDS) in the assessment of vascular pattern and vessel displacement of cervical lymph nodes. Colour Doppler (2-D CDS), power Doppler (2-D PDS) and 3-D power Doppler sonograms (3D PDS) of 145 cervical nodes were reviewed (metastases n=60, lymphoma n=30, tuberculosis n=23, reactive n=25, Kimura disease n=7). Sonograms of the three imaging modes were reviewed separately with an interval of 2 weeks. Lymph nodes were assessed for the vascular pattern (hilar, peripheral or mixed) and the presence or absence of displacement of hilar vascularity. For the assessment of displacement of hilar vascularity, only lymph nodes that showed hilar or mixed vascularity in the three imaging modes were included in the analysis. Results showed that there was a high level of agreement between CDS and PDS in assessment of vascular patterns (kappa=0.914), whereas the level of agreement between CDS and 3-D PDS (kappa=0.484) and between PDS and 3-D PDS (kappa=0.452) was low. There was a high level of agreement in the assessment of displacement of hilar vascularity among the three imaging modes (CDS and PDS, kappa=0.942; CDS and 3-D PDS, kappa=0.808; PDS and 3-D PDS, kappa=0.865). In the assessment of vascular patterns of cervical lymphadenopathy, CDS and PDS have a similar performance. However, accurate assessment of the vascular pattern of cervical nodes may be difficult using 3-D PDS. In the assessment of displacement of hilar vascularity, the performances of CDS, PDS and 3-D PDS are similar.

Adolescent↗

Measurement of ultrasonic power and electro-acoustic efficiency of high power transducers.

In this paper, an improved method for the measurement of acoustic power and electro-acoustic efficiency of high power ultrasonic transducers is presented. The measuring principle is described, the experimental results are given. In comparison with traditional methods, the method presented in this paper has the advantages of simplicity, economy and practicality. The most important is that it can measure the output acoustic power and the electro-acoustic efficiency of the transducer under the condition of high power and practical applications, such as ultrasonic cleaning and soldering.

Electricity↗