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PubMed1997

Power cuts and EPI vaccine storage.

OBJECTIVE: To study the integrity of EPI vaccine storage during interruptions to the power supply. SETTING: Health centres in Colombo District. METHOD: An interviewer-administered questionnaire was used to collect information on staff compliance with regulations of the expanded program of immunisation (EPI) and alternative facilities available for refrigeration during power failure. The refrigerator and storage conditions were inspected. The stored vaccines were tagged with thermosensitive cold chain monitors, which were read on revisiting the clinic 14 days later. During the study period, power cuts of 2 hours' duration were in force daily. A control study was carried out when there was no interruption to power supply. RESULTS: Diphtheria-pertussis-tetanus (DPT) and measles vaccines had been exposed to temperatures outside the prescribed range during power cuts. Oral polio vaccine had adequate storage with power cuts of 2 hours' duration. CONCLUSION: Alternative facilities for vaccine storage during power cuts were not available and the potency of DPT and measles vaccines were compromised with interruptions to power of 2 hours' duration or more.

Drug Storage↗

PubMed1998

Power Doppler sonography of cervical lymph nodes in patients with head and neck cancer.

PURPOSE: The purpose of this preliminary study was to evaluate the usefulness of power Doppler sonography in differentiating metastatic from nonmetastatic cervical lymph nodes in patients with cancer. METHODS: Histologically proved metastatic (n = 71) and nonmetastatic (n = 220) lymph nodes were examined with power Doppler sonography in 77 patients with head and neck cancer. Power Doppler sonography was assessed for its ability to differentiate metastatic from nonmetastatic lymph nodes. RESULTS: Power Doppler sonography showed characteristic features of parenchymal blood flow signal in 59 (83%) of the 71 metastatic lymph nodes. By contrast, only four (2%) of the 220 nonmetastatic nodes showed these power Doppler signals. In addition, power Doppler sonography showed high levels of sensitivity (83%) and specificity (98%) in depicting metastatic lymph nodes, which were superior to the values (66% sensitivity and 92% specificity) obtained by applying size criteria (transverse to longitudinal ratio). However, a combination of the two criteria (parenchymal color signal and transverse to longitudinal ratio) improved diagnostic accuracy to 92% sensitivity and 100% specificity. CONCLUSION: Our preliminary findings suggest that the power Doppler criteria of no hilar flow, peripheral parenchymal nodal flow, and a transverse to longitudinal ratio of more than 0.65 together constitute a powerful tool for depicting metastatic lymph nodes in patients with cancer.

Adult↗

PubMedDate not supplied

Rural women and power in Pakistan.

Perceptions of power in women living in rural villages in Pakistan were explored. The Lee-Hezekiah Power Perception Scale was developed by the authors to measure women's perception of their power. The instrument was administered in interviews conducted by a group of Lady Health Visitors who were participating in a project funded by the Canadian International Development Agency. Sixty-nine women ranging in age from 20 to 65 were interviewed. One-way analysis of variance revealed that the oldest group perceived themselves to have more power than the youngest group perceived themselves to have. Stepwise multiple regression indicated that the number of male children a woman had was predictive of the amount of power she perceived herself to have. The results are discussed in relation to existing literature on women and power in developing countries. Implications for further research on women's perceptions of power and health are discussed.

Adult↗

PubMed2003

Waveform magnetic field survey in Russian DC and Swiss AC powered trains: a basis for biologically relevant exposure assessment.

Recent epidemiological studies suggest a link between transport magnetic fields (MF) and certain adverse health effects. We performed measurements in workplaces of engineers on Russian DC and Swiss AC powered (16.67 Hz) electric trains using a computer based waveform capture system with a 200 Hz sampling rate. MF in DC and AC trains show complex combinations of static and varying components. The most probable levels of quasistatic MF (0.001-0.03 Hz) were in the range 40 microT. Maximum levels of 120 microT were found in DC powered locomotives. These levels are much higher than the geomagnetic field at the site of measurements. MF encountered both in DC and AC powered rail systems showed irregular temporal variability in frequency composition and amplitude characteristics across the whole frequency range studied (0-50 Hz); however, more than 90% of the magnetic field power was concentrated in frequencies </=16.67 Hz. In AC locomotives, such as the most popular engine Re 4/4 II, the major energy falls around the fundamental frequency 16.67 Hz, with an average magnetic field intensity of about 44 microT; moreover, a significant contribution (about 15%) is due to components below the fundamental frequency. In Russian DC powered trains amplitudes of field variations sharply decrease from static to approximately 3-4 Hz fields; for higher frequencies a tendency of slow decrease is observed up to 50 Hz. For frequencies higher than 1 Hz average amplitudes of magnetic field variations are less than 1 microT; maximum levels reach tens of microtesla. At frequencies lower than 15 Hz, the average magnetic field generated by Swiss AC powered locomotives was approximately 10 times greater than fields observed in Russian DC powered trains.

Electric Power Supplies↗

PubMed2003

Power requirements for vibrotactile piezo-electric and electromechanical transducers.

Human-machine information transfer through tactile excitation has addressed new applications in virtual reality, robotics, telesurgery, sensory substitution and rehabilitation for the handicapped in the past few years. Power consumption is an important factor in the design of vibrotactile displays, because it affects energy needs and the size, weight, heat dissipation and cost of the associated electronics. An experimental study is presented on the power required to reach tactile thresholds in electromechanical and piezo-electric transducers. Three different waveforms are considered, with an excitatory period formed by a burst of rectangular 50% duty cycle pulses (R50), rectangular low duty cycle pulses (RLO) and sinusoidal pulses (SIN). Ten different pulse repetition periods (RPs) were considered in the range 1/550-1/25 s. The voltage and current waveforms applied to the transducers at sensation thresholds in a group of 12 healthy subjects were sampled and stored in a digital oscilloscope. The average power was determined for each subject, and differences of two orders of magnitude were measured between the electromechanical and the piezo-electric transducer power consumption. Results show that, for the electromechanical transducer, a smaller power consumption of 25 microW was determined for RP = 1/25 s and the RLO waveform. In the case of the piezo-electric transducer, power of 0.21 microW was determined for SIN excitation and RP = 1/250 s. These results show the advantages of reducing power requirements for vibrotactile displays, which can be optimised by the choice of appropriate types of transducer, excitatory waveforms and pulse repetition periods.

Adult↗

PubMed2005

Evaluation of the emission characteristics of trace metals from coal and fuel oil fired power plants and their fate during combustion.

Coal as well as fuel oil combustion generates emissions of potentially toxic trace pollutants including organic and inorganic chemical compounds besides major pollutants. A study on As, Cd, Co, Cr, Cu, Hg, Fe, Mn, Ni, Pb, Se, and Zn emissions from a 220 MW coal-fired power plant equipped with a electrostatic precipitators (ESPs) and 6 MW oil fired-power plant was carried out, using stack monitoring kit, Envirotech APM 620, which is similar to EPA Method 29. Simultaneous sampling of coal, fuel oil, oil waste, bottom ash, fly ash, flue gases, and particles associated with the gas phase has been performed. This sampling method was used for trace metal sampling. The content of all these metals in coal, oil, oil waste, bottom ash, fly ash have been determined by XRF, whereas their contents in the flue gases, and particles associated with the gas phase has been analyzed with ICP-AES. The mass balances obtained for trace elements were satisfactory in case of fuel oil based power plant, whereas in case of coal fired power plant, the mass balance for all the trace elements were below 50% except for the As, Se, and Hg. The enrichment factors for all trace metals was <1 in both cases. The above sampling method is moderately adequate method for trace element sampling in coal as well as oil fired power plants except for Hg. The results indicate that trace metals emissions were higher in coal-based power plant than the fuel oil-fired power plant.

Air Pollutants↗

PubMed2005

Emissions of mercury and other trace elements from coal-fired power plants in Japan.

To evaluate trace element emissions from modern coal-fired power plants into the atmospheric environment in Japan, trace elements in the coal used in electric utility boilers, stack concentrations, emission rates and emission ratios of coal-fired power plants, and proportions of trace elements in coal-fired power plants were studied. The elements were As, B, Be, Cd, Co, Cr, F, Hg, Mn, Ni, Pb, Sb, Se and V, which are designated in the Law of Pollutant Release and Transfer Register. The particulate trace elements were collected in an electrostatic precipitator and a wet desulfurization scrubber. Emissions into the atmosphere were lower than 1% of the quantity in coal, but the volatile trace elements showed somewhat higher emission ratios. For mercury, the mean concentration in coal was 0.045 ppm, the mean emission rate was 4.4 microg/kW h, and the mean emission ratio was 27%, the highest ratio among all elements in this study. The total annual emission of mercury from coal-fired power plants of the electric power industry in Japan was estimated to be 0.63 t/y. On the basis of these data, the atmospheric environment loads from a coal-fired power station were investigated. The calculation of stack gas dispersion showed that maximum annual mean ground level concentrations were in the order of 10(-2) to 10(-5) of the background concentrations, and that the adverse effect of the emissions from the coal-fired power station was small.

Air Pollutants↗

PubMed2003

The influence of partner drug use and relationship power on treatment engagement.

Substance-using intimate partners negatively influence individuals' substance abuse treatment engagement and drug use, but little else is known about effects of intimate relationships on treatment. We examine how relationship dynamics (power, control, dependence, insecurity and decision-making power) influence treatment engagement, and whether this differs by gender and partner drug use. Sixty-four heroin users (42 men, 22 women) receiving methadone detoxification treatment in Los Angeles were interviewed at treatment entry and submitted daily diaries of drug use throughout the 21-day treatment. Total number of reported heroin-free days in the first eight treatment days was the dependent variable. Bivariate analyses revealed, that compared to men, women were more likely to have substance-using partners, reported greater power over a partner and greater household decision-making power in their relationships. Multivariate analysis indicated that individuals whose partners had more control over them reported fewer days abstinent. Among individuals with heroin-using partners, greater household decision-making power was associated with more days abstinent, but there was no association for individuals with non-using partners. Relationship power dynamics may be important influences on the treatment process, and some dimensions of power may interact with partner drug use status.

Adult↗

PubMedDate not supplied

Impact of 2003 power outages on public health and emergency response.

INTRODUCTION: In 2003, a major power outage occurred in the midwest and northeast United States affecting some 50 million people. The power outages affected multiple systems in state and local municipalities and, in turn, affected public health. METHODS: Semi-structured interviews were conducted using open-ended questionnaires, with a convenience sample of state- and locally selected subject matter experts from Ohio, Michigan, and New York. Respondents were interviewed in groups representing one of five areas of interest, including: (1) emergency preparedness; (2) hospital and emergency medical services; (3) municipal environmental systems; (4) public health surveillance and epidemiology; and (5) psychosocial and behavioral issues. The reported positive and negative impacts of the power outage on public health, medical services, and emergency preparedness and response were documented. Responses were categorized into common themes and recommendations were formulated. RESULTS: The amount of time that the respondents' locations were without power ranged from <1 hour to 52 hours. Many common themes emerged from the different locations, including communications failures, alternate power source problems, manpower and training issues, and psychosocial concerns. There was minimal morbidity and mortality reported that could be attributed to the event. CONCLUSION: Power outages negatively impacted multiple municipal infra-structures, and affected medical services, emergency response, and public health efforts. Previous federal funding positively impacted public health and emergency response capabilities. Recommendations were made based upon the common themes identified by the respondents. Recommendations may assist state and local health departments, medical service providers, and emergency responders in planning for future power outage problems.

Disaster Planning↗

PubMed2001

Do HMOs have monopsony power?

OBJECTIVE: To determine whether health maintenance organizations (HMOs) have monopsony power in the markets for ambulatory care and inpatient hospital services. DATA SOURCES: A pooled time-series of data on all HMOs operating in the United States from 1985 through 1997. Information reported to InterStudy on HMO market areas and enrollment is linked to financial data reported to state regulators and county characteristics from the Area Resource File (ARF). STUDY DESIGN: We use a two-stage design to test for the existence of monopsony power. First, we estimate regression equations for the prices paid by HMOs for ambulatory visits and inpatient hospital days. The key independent variable is a measure of the importance of an individual HMO as a buyer of ambulatory care or hospital services. Second, we estimate regressions for the utilization of ambulatory visits and inpatient hospital days per HMO enrollee, as a function of HMO buying power and other variables. PRINCIPAL FINDINGS: Increased HMO buying power is associated with lower price and higher utilization of hospital services. Buying power is not related to ambulatory visit price or utilization per member. CONCLUSIONS: Our findings are not consistent with the monopsony hypothesis. They suggest that managed care organizations have contributed to a welfare-increasing breakup of hospital monopoly power. The role of HMOs as buyers of ambulatory services is more complex. We discuss possible reasons why buying power may not affect price or utilization of ambulatory visits.

Ambulatory Care↗

PubMed2003

Power in stereotypically masculine domains: a Social Influence Strategy X Stereotype Match model.

This work examines the hypothesis that stereotypes of groups to which low-power people belong should influence the perceptions and behavior of powerful people only when those stereotypes are both contextually relevant (e.g., women in masculine domains) and provide information of relevance given powerful people's beliefs about the relation between subordinates and goal attainment. Findings across two studies supported predictions. In a masculine domain, when high-power men were attentive to subordinate weaknesses that may produce thwarts to goal attainment, stereotypes of women defined the contextually relevant shortcomings of women, and stereotype-consistent high-power behaviors ensued. In contrast, when powerful men were attentive to subordinate strengths that may enhance goal strivings, stereotypes of women were uninformative (i.e., did not contain information about relevant strengths); female and male employees were responded to and, in turn, performed and reacted similarly. The implications of these findings for theorizing on the relation between power and stereotyping are discussed.

Achievement↗

PubMed2005

Your highness: vertical positions as perceptual symbols of power.

Metaphorically, power equals up. Drawing on embodied theories of cognition, the author argues that thinking about power involves mental simulation of space and can be interfered with by perception of vertical differences. Study 1 assessed image schemas for power and found a shared vertical difference metaphor. Studies 2, 3, and 4 showed that the judgment of a group's power is influenced by the group's vertical position in space and motor responses implying vertical movement. Study 5 ruled out that the influence of vertical position on power judgments is driven by valence differences. Study 6 showed that vertical position also influences the power judgment result itself. The evidence suggests that the concept of power is partly represented in perceptual form as vertical difference.

Adult↗

PubMed2003

Happy affect and smiling: is their relation moderated by interpersonal power?

Three studies examined the hypothesis that the relation between self-rated happy affect and overall smiling during dyadic interactions is moderated by one's relative power. In all 3 studies, interpersonal power was experimentally manipulated, and smiling and self-reported happy affect were measured during and after the interaction, respectively. Happy affect was positively correlated with overall smiling for both low-power and high-power participants. Moreover, the correlations for both low- and high-power participants were comparable to those found when power roles were not unequal or made salient, based on analysis of the present studies as well as comparison with the previously published literature. Happy affect and overall smiling had a positive relation that was not moderated by interpersonal power.

Adult↗

PubMed2004

Speciation and mass-balance of mercury from pulverized coal fired power plants burning western Canadian subbituminous coals.

This report summarizes the results of a study carried out on six pulverized coal-fired power plants in western Canada burning subbituminous coal for the mass-balance and speciation of mercury. The main objectives of this study were to: determine the total gaseous mercury (TGM) emitted from stacks of power plants using the Ontario Hydro method; identify the speciation of emitted mercury such as metallic (Hg(0)) and gaseous elemental (GEM) mercury; and perform mass-balance calculations of mercury for milled-coal, bottom ash, electrostatic precipitators (ESP) fly ash and stack-emitted mercury based on three tests. Sampling of mercury was carried out using the Ontario Hydro method and mercury was determined using the USEPA method 7473 by cold vapor atomic absorption (CVAAS). The sample collection efficiencies confirmed that both oxidized and the elemental mercury had been successfully sampled at all power plants. The total gaseous mercury emitted (TGM) is 6.95-15.66 g h(-1) and is mostly in gaseous elemental mercury (GEM, Hg(0)) form. The gaseous elemental mercury is emitted at a rate of 6.59-12.62 g h(-1). Reactive gaseous mercury (RGM, Hg(2+)) is emitted at a rate of 0.34-3.68 g h(-1). The rate of emission of particulate mercury (Hg(p)) is low and is in the range 0.005-0.076 g h(-1). The range of mass-balances for each power plant is more similar to the variability in measured mercury emissions, than to the coal and ash analyses or process data. The mass-balance calculations for the six power plants, performed on results of the three tests at each power plant, are between 86% and 123%, which is acceptable and within the range 70-130%. The variation in mass-balance of mercury for the six power plants is mostly related to the variability of coal feed rate.

Air Pollutants↗

PubMed2003

Desperately seeking fusion: on 'joined-up thinking', 'holistic practice' and the new economy of welfare professional power.

This paper argues that social welfare research on joined-up thinking is underpinned by two theses. The 'systemic move' thesis suggests that joined-up thinking is needed to fill gaps in welfare service provision arising from a lack of interorganizational co-ordination. The 'epistemological move' thesis advises that joined-up thinking is needed to overcome deficiencies in the institutional division and distribution of welfare knowledge. Both theses macro-systematize blame for previous social welfare failures, and both are teleological because they present joined-up thinking as a progressive solution that results in a more effective (and thus less fallible) welfare system. In this paper, I argue thatjoined-up thinking can also create a new economy of welfare professional power. First, I show how some versions of 'joined-up' thinking manifest themselves in holistic practices that can 'see everything', 'know everything' and 'do anything', and thus a 'holistic power' to discipline and control every aspect of welfare recipients lives. Since holistic power is seen as infallible, its failure to produce 'active bodies' necessitates the creation of secondary 'joined-up powers' that individualize blame and exclude those to blame from welfare resources. These 'secondary powers' match the social disciplines enforced by one welfare agency (e.g. the responsibility to work enforced by the employment service) with legal rights under another agency (e.g. the right to housing from social landlords), so that breach of the former leads to exclusion from the latter. I conclude that this power strategy is primitive and punitive because it simply excludes welfare recipients. Exclusion is also uneconomic because it pushes welfare recipients into the shade of welfare institutional power.

Employment↗

PubMed2000

Power and influence in clinical effectiveness and evidence-based medicine.

BACKGROUND: The need to base clinical interventions on valid findings of research has been a dominant theme in clinical practice during the last quarter of a century. However, there is much evidence showing that research evidence reaches everyday practice slowly. Solutions to this problem include evidence-based practice and implementation by guidelines and audit. Studies of these methods have included surveys of clinicians' views, implementation projects and evaluations of educational interventions, but they have not examined their implications for the power structure of clinical organizations. This is surprising, given the emphasis placed on medical power in sociological studies of health care. METHODS: A framework derived from management theory defines and summarizes theories of power and influence under the headings: sources of power, overt methods of influence, unseen or covert methods of influence and individual response to influence. This framework is then used to analyse the power and influence possessed and exerted by general practitioners (GPs) and hospital consultants and how these are affected by evidence-based practice and guidelines and audit programmes. OUTCOMES: GPs are seen as having less expert power than consultants and to be more compliant with externally managed guidelines and audit programmes. It is pointed out that compliance with guidelines and audit programmes helps GPs to meet their contractual requirement to be involved in clinical audit activities. Evidence-based practice, which directly challenges the authority of expert opinion is seen as a threat to the power of consultants, but a potential opportunity for GPs and other clinicians whose status is traditionally lower.

Evidence-Based Medicine↗

PubMed2005

Responsibly managing the medical school--teaching hospital power relationship.

The relationship between medical schools and their teaching hospitals involves a complex and variable mixture of monopoly and monopsony power, which has not been previously been ethically analyzed. As a consequence, there is currently no ethical framework to guide leaders of both institutions in the responsible management of this complex power relationship. The authors define these two forms of power and, using economic concepts, analyze the nature of such power in the medical school-teaching hospital relationship, emphasizing the potential for exploitation. Using concepts from both business ethics and medical ethics, the authors analyze the nature of transparency and co-fiduciary responsibility in this relationship. On the basis of both rational self-interest, drawn from business ethics, and co-fiduciary responsibility, drawn from medical ethics, they argue for the centrality of transparency in the medical school-teaching hospital relationship. Understanding the ethics of monopoly and monopsony power is essential for the responsible management of the complex relationship between medical schools and their teaching hospitals and can assist the leadership of academic health centers in carrying out one of their major responsibilities: to prevent the exploitation of monopoly power and monopsony power in this relationship.

Academic Medical Centers↗

PubMed1992

Total electrical power failure in a cardiothoracic intensive care unit.

OBJECTIVE: To describe the management of patients in an ICU during failure of both primary and backup electrical systems, resulting in nonfunctioning monitors, mechanical ventilators, and other life-support equipment. DESIGN: Case report of power outage and discussion. SETTING: A 45-bed cardiothoracic surgical ICU in a tertiary-care teaching hospital. PATIENTS: Postoperative cardiothoracic surgical patients receiving i.v. infusions of vasoactive medications and mechanical ventilatory support. MAIN RESULTS: Support measures included the use of pneumatically powered mechanical ventilators, battery-operated transport monitors and infusion pumps, and recruitment of non-ICU personnel to assist with manual ventilation and patient care. Problems identified included communication difficulties caused by failure of electronic telephones, and physical access limitation due to failure of electrical door openers and security locks. CONCLUSIONS: Total electrical power failure can occur even when an emergency power system is in place. Although the occurrence of such failure is unlikely, provisions must be made for its occurrence in order to avoid catastrophic patient injury. Such provisions include a mental plan of action, provision of emergency support equipment, physical plant changes, and the provision of power-independent communication systems. Power demands and battery backup capability of equipment should be considered in future equipment purchases. The ICU staff should be aware of the structure and operation of backup electrical power sources.

Coronary Care Units↗