Spatially averaged model of complex-plasma discharge with self-consistent electron energy distribution

A global, or averaged, model for complex low-pressure argon discharge plasmas containing dust grains is presented. The model consists of particle and power balance equations taking into account power loss on the dust grains and the discharge wall. The electron energy distribution is determined by a Boltzmann equation. The effects of the dust and the external conditions, such as the input power and neutral gas pressure, on the electron energy distribution, the electron temperature, the electron and ion number densities, and the dust charge are investigated. It is found that the dust subsystem can strongly affect the stationary state of the discharge by dynamically modifying the electron energy distribution, the electron temperature, the creation and loss of the plasma particles, as well as the power deposition. In particular, the power loss to the dust grains can take up a significant portion of the input power, often even exceeding the loss to the wall.

Discharge mode transitions in low-frequency inductively coupled plasmas with internal oscillating current sheets

Transitions between the two discharge modes in a low-frequency (∼460 kHz) inductively coupled plasma sustained by an internal oscillating radio frequency (rf) current sheet are studied. The unidirectional rf current sheet is generated by an internal antenna comprising two orthogonal sets of synphased rf currents driven in alternately reconnected copper litz wires. It is shown that in the low-to-intermediate pressure range the plasma source can be operated in the electrostatic (E) and electromagnetic (H) discharge modes. The brightness of the E -mode argon plasma glow is found remarkably higher than in inductively coupled plasmas with external flat spiral "pancake" coils. The cyclic variations of the input rf power result in pronounced hysteretic variations of the optical emission intensity and main circuit parameters of the plasma source. Under certain conditions, it appears possible to achieve a spontaneous E→H transition ("self-transition"). The observed phenomenon can be attributed to the thermal drift of the plasma parameters due to the overheating of the working gas. The discharge destabilizing factors due to the gas heating and step-wise ionization are also discussed. © 2005 American Vacuum Society.

Microwave plasma discharge produced and sustained by the surface wave propagating along a metal wire

A theoretical model of the plasma discharge in a metal cylinder pumped by an operating gas of an arbitrary nature is presented. The ionization is carried out by the surface wave (SW) propagating along a coaxial metal wire. The model includes the local dispersion relation, the energy balance equation, and the relation between the absorbed power per unit length and the local plasma density. Two typical regimes of the discharge are analyzed. In both regimes the axial and radial profiles of the plasma density of the electromagnetic field components and of the SW intensity are obtained. The possible use of the obtained results in plasma technology are discussed.

Microwave gas discharge produced and sustained by a surface wave propagating along a cylindrical metal antenna with a dielectric coating

The structure of a microwave gas discharge produced and sustained by a surface wave (SW) propagating along a cylindrical metal antenna with a dielectric coating is studied. The SW that produces and sustains the microwave gas discharge propagates along an external magnetic field and has an eigenfrequency in the range between the electron cyclotron and electron plasma frequencies. The presence of a dielectric (vacuum) sheath region separating the antenna from the plasma is assumed. The spatial distributions of the produced plasma density, electromagnetic fields, energy flow density, phase velocity and reverse skin depth of the SW are obtained analytically and numerically.

Discharge practices for the intensive care patient : a qualitative exploration in the general ward setting

OBJECTIVE: To explore how registered nurses (RNs) in the general ward perceive discharge processes and practices for patients recently discharged from the intensive care unit (ICU). BACKGROUND: Patients discharged from the ICU environment often require complicated and multifaceted care. The ward-based RN is at the forefront of the care of this fragile patient population, yet their views and perceptions have seldom been explored. DESIGN: A qualitative grounded theory design was used to guide focus group interviews with the RN participants. METHODS: Five semi-structured focus group interviews, including 27 RN participants, were conducted in an Australian metropolitan tertiary referral hospital in 2011. Data analyses of transcripts, field notes and memos used concurrent data generation, constant comparative analysis and theoretical sampling. RESULTS: Results yielded a core category of 'two worlds' stressing the disconnectedness between ICU and the ward setting. This category was divided into sub categories of 'communication disconnect' and 'remember the family'. Properties of 'what we say', 'what we write', 'transfer' and 'information needs' respectively were developed within those sub-categories. CONCLUSION: The discharge process for patients within the ICU setting is complicated and largely underappreciated. There are fundamental, misunderstood differences in prioritisation and care of patients between the areas, with a deep understanding of practice requirements of ward based RNs not being understood. The findings of this research may be used to facilitate inter departmental communications and progress practice development.

A critical evaluation of written discharge advice for people with mild traumatic brain injury : what should we be looking for?

Objective: To formally evaluate the written discharge advice for people with mild traumatic brain injury (mTBI). Methods: Eleven publications met the inclusion criteria: (1) intended for adults; (2) ≤two A4 pages; (3) published in English; (4) freely accessible; and (5) currently used (or suitable for use) in Australian hospital emergency departments or similar settings. Two independent raters evaluated the content and style of each publication against established standards. The readability of the publication, the diagnostic term(s) contained in it and a modified Patient Literature Usefulness Index (mPLUI) were also evaluated. Results: The mean content score was 19.18 ± 8.53 (maximum = 31) and the mean style score was 6.8 ± 1.34 (maximum = 8). The mean Flesch-Kincaid reading ease score was 66.42 ± 4.3. The mean mPLUI score was 65.86 ± 14.97 (maximum = 100). Higher scores on these metrics indicate more desirable properties. Over 80% of the publications used mixed diagnostic terminology. One publication scored optimally on two of the four metrics and highly on the others. Discussion: The content, style, readability and usefulness of written mTBI discharge advice was highly variable. The provision of written information to patients with mTBI is advised, but this variability in materials highlights the need for evaluation before distribution. Areas are identified to guide the improvement of written mTBI discharge advice.

Demographics and discharge outcomes of dysvascular and non-vascular lower limb amputees at a subacute rehabilitation unit: A 7-year series

Objective To examine personal and social demographics, and rehabilitation discharge outcomes of dysvascular and non-vascular lower limb amputees. Methods In total, 425 lower limb amputation inpatient rehabilitation admissions (335 individuals) from 2005 to 2011 were examined. Admission and discharge descriptive statistics (frequency, percentages) were calculated and compared by aetiology. Results Participants were male (74%), aged 65 years (s.d. 14), born in Australia (72%), had predominantly dysvascular aetiology (80%) and a median length of stay 48 days (interquartile range (IQR): 25–76). Following amputation, 56% received prostheses for mobility, 21% (n = 89) changed residence and 28% (n = 116) required community services. Dysvascular amputees were older (mean 67 years, s.d. 12 vs 54 years, s.d. 16; P < 0.001) and recorded lower functional independence measure – motor scores at admission (z = 3.61, P < 0.001) and discharge (z = 4.52, P < 0.001). More nonvascular amputees worked before amputation (43% vs 11%; P < 0.001), were prescribed a prosthesis by discharge (73% vs 52%; P < 0.001) and had a shorter length of stay (7 days, 95% confidence interval: –3 to 17), although this was not statistically significant. Conclusions Differences exist in social and demographic outcomes between dysvascular and non-vascular lower limb amputees.

Nutrient discharge to groundwater at the Kaharoa rainfall recharge site, Rotorua [GNS Science Consultancy Report 2008/320]

Environment Bay of Plenty Commissioned GNS Science to measure nitrogen and phosphorus concentrations in rainfalla nd rainfall recharge to groundwater at the Kaharoa rainfall recharge site. The aim of this work is to determine nutrient concentrations in rainfall recharge to groundwater and rainfall under pasoral land use.

Quality of discharge summaries sent by a regional hospital to general practitioners

Background A comprehensive hospital discharge summary sent to the patient's general practitioner in a timely manner can ease patient transition between care settings. Aim To investigate the quality of discharge summaries sent by a regional hospital to GPs; and to evaluate GPs' satisfaction with the medication list contained in the discharge summary. Method A questionnaire was mailed to a sample of 80 Gold Coast GPs who had made more than five referrals to the Gold Coast Hospital during June 2009. Results 18 responses (23% response rate) were received from September to October 2009. The majority (67%) of GPs received discharge summaries from the hospital and they were mostly in an electronic format with attached medication lists. The reasons for changing medications were not well explained and the timeframe for receiving summaries was considered unsatisfactory. Overall, the majority of GPs were satisfied with the quality of the discharge summaries. Conclusion GPs mostly received the discharge summaries and the majority received them electronically. The majority of GPs indicated that the medication lists were often attached to the discharge summaries and changes to medications recorded.

Water use and wastewater discharge of industrial sector in China

Problem of water scarcity has been increasingly severe in China. Though industrial sectors play important role for the rapid economic growth, and they consumes water and discharge wastewater. The purpose of this study is to examine the efficiency of water use and wastewater discharge in comparison with those of other inputs and production output in Chinese industry. Measuring efficiency of each input and output factor from 2002 to 2008, we find the average inefficiencies of industrial water use and industrial wastewater discharge are higher than those of capital, labor, and production output in China. In addition, the productivity levels to save water in the water shortage areas are not higher compared to the others. The water use inefficiency has a high dispersion especially in the regions where the amounts of water resources per capita is less than 3000 cubic meter.

Experiences of male patients and wife-caregivers in the first year post-discharge following minor stroke: A descriptive qualitative study

Background Most patients with minor stroke are discharged directly home from acute care, under the assumption that little will be required in the way of adaptation and adjustment because informal caregivers will manage the stroke recovery process. We explored male patients with minor stroke and their wife-caregivers' perceptions of factors affecting quality of life and caregiver strain encountered during the first year post-discharge. Methods Data were obtained from responses to two open-ended questions, part of quality of life and caregiver strain scales administered to participants in a larger descriptive study. Conventional content analysis was used to assess narrative accounts of living with minor stroke provided by 26 male patients and their wife-caregivers over a period of 1-year post-discharge. Results Two major themes that emerged from these data were 'being vulnerable' and 'realization'. Subthemes that arose within the vulnerability theme included changes to patients' masculine image and wife-caregivers' assumption of a hyper-vigilance role. In terms of 'realization' patients and their wife-caregivers shared 'loss' as well as 'changing self and relationships'. Patients in this study focused primarily on their physical recovery and their perceptions of necessary changes. Wife-caregivers were actively involved in managing the day-to-day demands that stroke placed on individual, family and social roles. Conclusions We conclude that patients and wife-caregivers expend considerable time and energy reestablishing control of their lives following minor stroke in an attempt to incorporate changes to self and their relationship into the fabric of their lives.

Novel window coupler for the detection of partial discharge activity in GIS

This work investigates the feasibly in using a low noise “C” Band block down-converter as a Ultra High Frequency window coupler for the detection of partial discharge activity from free conducting practices and a protrusion on the high voltage conductor in Gas Insulated Switchgear. The investigated window coupler has a better sensitivity than the internal Ultra High Frequency couplers fitted to the system. The investigated window couplers however are sensitive to changes in the frequency content of the discharge signals and appear to be less sensitive to negative discharges signals produced by a protrusion than the positive discharge signals.

Characteristics of the first pre-discharge current pulse in SF6 under a steep fronted impulse voltage

An improved understanding of the characteristics of the pre-discharge current pulses in GIS will lead to improved analyses of the results from the UHF partial discharge detection method. This paper presents the characteristics of the first pre-discharge current pulses from a point-to-plain geometry at 1 bar absolute under both polarities of a 1.1/80 us lightning impulse. The analysis has shown that the pre-discharge current wave shape, peak current magnitude and charge is effected by the instantaneous voltage at which the pre- discharge took place as well as the polarity of the active electrode. The measured results show that protrusions on the electrodes have slower wave shape parameters than those reported for free conducting particles.