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S Wilkinson

Publications and source records attributed to S Wilkinson.

At least 19 recordsLinked to original sources
PubMed2001

System validation and work practice efficiency gains of a new localization method for stereotactic radiotherapy.

The increased procedural demands of stereotactic localization techniques when compared with conventional treatment practices reduces machine efficiency, an outcome likely to be greatly magnified by the introduction of fractionation to stereotactic techniques. Currently in Australia and New Zealand there are no guidelines for the definition of efficiency. We sought to devise a system to simultaneously validate the accuracy and efficiency of the technique. The frameless relocation methods employed in the Medtronic Sofamor Danek (MSD) stereotactic radiotherapy (SRT) system were studied in the clinical setting. Accuracy has been determined according to the accumulation of errors throughout the planning and treatment process. The clinical demands of the system (staffing and resources) were analysed relative to conventional treatment approaches. Timing studies indicate a mean time of 19.7 min for treatment of a daily SRT fraction (4-5 arcs, single isocentre). Cost and staffing requirements are similar to those for conventional radiotherapy. It is concluded that with the system used, SRT is efficient for routine clinical implementation, with the level of efficiency increasing with increasing patient numbers. It is recommended that a common acceptance standard be developed to allow cross-institutional comparison of the clinical efficiency of new treatment techniques.

Brain Neoplasms↗
PubMed2001

Rapid low temperature-induced stomatal closure occurs in cold-tolerant Commelina communis leaves but not in cold-sensitive tobacco leaves, via a mechanism that involves apoplastic calcium but not abscisic acid.

Commelina communis stomata closed within 1 h of transferring intact plants from 27 degrees C to 7 degrees C, whereas tobacco (Nicotiana rustica) stomata did not until the leaves wilted. Abscisic acid (ABA) did not mediate cold-induced C. communis stomatal closure: At low temperatures, bulk leaf ABA did not increase; ABA did not preferentially accumulate in the epidermis; its flux into detached leaves was lower; its release from isolated epidermis was not greater; and stomata in epidermal strips were less sensitive to exogenous ABA. Stomata of both species in epidermal strips on large volumes of cold KCl failed to close unless calcium was supplied. Therefore, the following cannot be triggers for cold-induced stomatal closure in C. communis: direct effects of temperature on guard or epidermal cells, long-distance signals, and effects of temperature on photosynthesis. Low temperature increased stomatal sensitivity to external CaCl(2) by 50% in C. communis but only by 20% in tobacco. C. communis stomata were 300- to 1,000-fold more sensitive to calcium at low temperature than tobacco stomata, but tobacco epidermis only released 13.6-fold more calcium into bathing solutions than C. communis. Stomata in C. communis epidermis incubated on ever-decreasing volumes of cold calcium-free KCl closed on the lowest volume (0.2 cm(3)) because the epidermal apoplast contained enough calcium to mediate closure if this was not over diluted. We propose that the basis of cold-induced stomatal closure exhibited by intact C. communis leaves is increased apoplastic calcium uptake by guard cells. Such responses do not occur in chill-sensitive tobacco leaves.

Abscisic Acid↗
PubMed2000

Thinking differently about thinking positive: a discursive approach to cancer patients' talk.

There is an extensive social science and psycho-oncology literature on coping with cancer which claims that "thinking positive" is correlated with--and, by extension, causally implicated in--individuals' morbidity and mortality rates, and their overall level of mental health. Drawing on our own data, in which groups of women with breast cancer talk about "thinking positive", this paper interrogates the basis of such claims from a discursive perspective, by challenging the data analyses upon which they are based. We show that previous literature overwhelmingly relies on self-report data, which are taken as offering more or less accurate depictions of speakers' psychological states (i.e. their mental adjustment or coping style). A discursive approach, by contrast, explores talk as a form of action designed for its local interactional context, and pays detailed attention to what statements about "thinking positive" actually mean for speakers in the contexts in which they occur. We show that "thinking positive" functions not as an accurate report of a internal cognitive state, but rather as a conversational idiom, characterised by vagueness and generality, and summarising a socially normative moral requirement; we also show that even those breast cancer patients who report "thinking positive" can also actively resist its moral prescriptions. Finally, we sketch out the implications of our analysis for analyses of cancer patients' talk more generally and for future research on coping with cancer.

Breast Neoplasms↗
PubMed2000

Commodification arguments for the legal prohibition of organ sale.

The commercial trading of human organs, along with various related activities (for example, advertising) was criminalised throughout Great Britain under the Human Organ Transplants Act 1989. This paper critically assesses one type of argument for this, and similar, legal prohibitions: commodification arguments. Firstly, the term 'commodification' is analysed. This can be used to refer to either social practices or to attitudes. Commodification arguments rely on the second sense and are based on the idea that having a commodifying attitude to certain classes of thing (e.g. bodies or persons) is wrong. The commodifying attitude consists of three main elements: denial of subjectivity, instrumentality, and fungibility. Secondly, in the light of this analysis, the claim that organ sale involves commodifying the human body is examined. This claim is found to be plausible but insufficient to ground an argument against organ sale, because the very same commodifying attitude is likely to be present in cases of (unpaid) organ donation. It is also argued that commodifying bodies per se may not be wrong. Thirdly, the view that organ sale involves commodifying persons is examined. Although this and the claim that it is wrong to commodify persons are probably true, there is--it is argued--little reason to regard organ sale as worse in this respect than other widely accepted practices, such as the buying and selling of labour. The conclusion is that although commodification is a useful ethical concept and although commodification arguments may sometimes be successful, the commodification argument against organ sale is not persuasive. This is not to say, though, that there are no arguments for prohibition--simply that this particular justificatory strategy is flawed.

Commerce↗
PubMed2000

Introduction and implementation of the basic treatment equivalent in a Varian-based department.

The increasing popularity of 3-D planning leads to procedural alterations as both workload and resource utilization increase. Although the complexity of the techniques has increased (as well as the set-up and treatment times), the workload statistics must still include the number of fields treated. It is commonly known that machine statistics of fields treated per day do not accurately represent workload because there are major differences between techniques. A mantle treatment technique and an opposed spine technique both have (statistically) two fields, although the set-up requirements and treatment times are very different. A basic treatment equivalent (BTE) formula was reported in early 1999 by Delaney et al. and incorporates a large number of variables inherent in patient treatment. The formula considers different factors that affect overall treatment time, and aims to represent a more accurate treatment time indicator. The aim of introducing the BTE into the Department of Radiation Oncology at Sir Charles Gairdner Hospital was to create a more accurate scheduling system and even out workloads on all treatment units. Therefore the BTE formula was used to assess accuracy of treatment times in order to determine if the values could be relied upon as accurate time indicators. Patients undergoing a variety of treatment techniques were timed for the duration of their treatment procedure, and their treatment times compared to the time estimated using the BTE formula. A few minor alterations were made to the equation for treatment units with multi-leaf collimation (MLC). A trial conducted at Sir Charles Gairdner Hospital found that, using the BTE formula (with a few modifications required for the MLC treatment units), of 60 patients timed for the duration of their set-up and treatment, 85% of values were in the range of +/- 3 min, and 95% were in the range of +/- 5 min of the estimated times. Through the routine use of the BTE equation a more sensitive indication of treatment machine workload can be found. Advantages such as: (i) a more accurate measure of treatment workload (for comparison with other departments) and (ii) increased scheduling accuracy will succeed over the currently accepted system of fields per hour.

Appointments and Schedules↗
PubMed2000

Evaluation of total volatile organic compound emissions from adhesives based on chamber tests.

In 1997, Homeswest in western Australia and Murdoch University developed a project to construct low-allergen houses (LAHs) in a newly developed suburb. Before the construction of LAHs, all potential volatile organic compound (VOC) emission materials used in LAHs are required to be measured to ensure that they are low total VOC (TVOC) emission materials. This program was developed based on this purpose. In recent times, the number of complaints about indoor air pollution caused by VOCs has increased. A number of surveys of indoor VOCs have indicated that many indoor materials contribute to indoor air pollution. Although some studies have been conducted on the characteristics of VOC emissions from adhesives, most of them were focused on VOC emissions from floor adhesives. Few measurements of VOC emissions from adhesives used for wood, fabrics, and leather are available. Furthermore, most research on VOC emissions from adhesives has been done in countries with cool climates, where ventilation rates in the indoor environment are lower than those in Mediterranean climates, due to energy conservation. VOCs emitted from adhesives have not been sufficiently researched to prepare an emission inventory to predict indoor air quality and to determine both exposure levels for the Australian population and the most appropriate strategies to reduce exposure. An environmental test chamber with controlled temperature, relative humidity, and airflow rate was used to evaluate emissions of TVOCs from three adhesives used frequently in Australia. The quantity of TVOC emissions was measured by a gas chromatography/flame ionization detector. The primary VOCs emitted from each adhesive were detected by gas chromatography/mass spectrometry. The temporal change of TVOC concentrations emitted from each adhesive was tested. A double-exponential equation was then developed to evaluate the characteristics of TVOC emissions from these three adhesives. With this double-exponential model, the physical processes of TVOC emissions can be explained, and a variety of emission parameters can be calculated. These emission parameters could be used to estimate real indoor TVOC concentrations in Mediterranean climates.

Adhesives↗
PubMed2000

Pallidotomy microelectrode targeting: neurophysiology-based target refinement.

OBJECTIVE: Microelectrode recording can refine targeting for stereotactic radiofrequency lesioning of the globus pallidus to treat Parkinson's disease. Multiple intraoperative microelectrode recording/stimulating tracks are searched and assessed for neuronal activity, presence of tremor cells, visual responses, and responses to kinesthetic input. These physiological data are then correlated with atlas-based anatomic data to approximate electrode location. On the basis of these physiological properties, one or more tracks are selected for lesioning. This study analyzes the track physiological factors that seem most significant in determining the microelectrode recording track(s) that will be chosen for pallidal lesioning. METHODS: Thirty-six patients with Parkinson's disease underwent microelectrode-guided pallidotomy. Between one and five microelectrode recording tracks were made per patient. Usually, one (n = 23) or two (n = 12) of these tracks were lesioned. Electrode positions in the x (mediolateral) and y (anteroposterior) axes were recorded and related to track neurophysiological findings and final lesion location. The stereotactic location and sequence of microelectrode tracks were recorded and plotted to illustrate individual search patterns. These patterns were then compared with those noted in other patients. Neurophysiological data obtained from recording tracks were analyzed. A retrospective analysis of track electrophysiology was performed to determine the track characteristics that seemed most important in the surgeon's choice of the track to lesion. Track physiological properties included general cell spike amplitude, tremor synchronous neuronal firing, kinesthetically responsive neuronal firing, and optic track responses (either phosphenes reported by the patient during track microstimulation or neuronal firing in response to light stimulus into the patient's eyes). Orthogonally corrected postoperative magnetic resonance images were used to confirm the anatomic lesion locations. RESULTS: In patients who had a single mapped track lesioned, specific track electrophysiological characteristics identified the track that would be lesioned most of the time (20 of 24 patients). Tracks that exhibited a combination of tremor synchronous firing, joint kinesthesia, and visual responsivity were lesioned 17 (85%) of 20 times. Analysis of intraoperative electrode movement in the x and y axes indicated a significant subset of moves but did not result in microelectrode positioning closer to the subsequently lesioned track. Accuracy of initial electrode movement in the x and y axes was most highly correlated with a measure of first-track electrophysiological activity. The number of microelectrode recording tracks did not correlate with clinical outcome. Anatomic analysis, using postoperative magnetic resonance imaging, revealed that all lesions were placed in the globus pallidus. Most patients (35 of 36) improved after surgery. CONCLUSION: The level of electrophysiological activity in the first track was the best predictive factor in determining whether the next microelectrode move would be closer to the ultimately lesioned track. The analysis of electrode track location and neurophysiological properties yields useful information regarding the effectiveness of microelectrode searching in the x and y axes. Within an institution, the application of this modeling method may increase the efficiency of the microelectrode refinement process.

Aged↗
PubMed1999

Educational campaign to improve the prevention of postoperative venous thromboembolism.

BACKGROUND: Recent studies have revealed considerable scope for improvement in preventing postoperative venous thromboembolism. This project comprised a baseline assessment of the use of preventive measures within the Royal Hobart Hospital, followed by the implementation and evaluation of an educational program directed at hospital staff. AIM: To determine whether the Royal Hobart Hospital's guidelines for the prophylaxis of postoperative venous thromboembolism were being utilized effectively and, if necessary, attempt to improve use of the guidelines through an educational programme. METHODS: Data were collected retrospectively from the medical records of 250 surgical patients undergoing a procedure during February 1997. Patients were classified as being at a low, medium or high risk of venous thromboembolism using two sets of criteria. The percentage of patients receiving the appropriate prophylaxis was determined. An educational programme to promote the hospital's guidelines for the prophylaxis of postoperative venous thromboembolism was then implemented. Included were presentations to staff, posters placed throughout the hospital and the wide distribution of the results and a glossy card showing the hospital's guidelines. Follow-up data were subsequently collected from another 250 surgical patients. RESULTS: Only 59% of patients received appropriate prophylaxis according to the hospital's approved guidelines, with little change when those patients with possible contraindications to thromboprophylaxis were excluded. When those patients at a high risk of venous thromboembolism were examined, only 25% were prescribed the recommended preventive measures. There was no difference between elective versus emergency surgery and the use of appropriate prophylaxis. Following the implementation of the educational programme, data collection from another 250 surgical patients revealed a significant increase (P < 0.05 by chi-square test) in the level of appropriate thromboprophylaxis to 70% of patients, with 77% of the high-risk patients being prescribed the recommended preventive measures. CONCLUSIONS: A pharmacy-based educational intervention significantly improved adherence to the hospital's guidelines for the prophylaxis of postoperative venous thromboembolism.

Australia↗
PubMed1999

Schering Plough clinical lecture communication: it makes a difference.

Communication is a vital component of nursing care that can improve outcomes for patients with cancer and their families in terms of psychological distress. Research indicates that nurses' communication skills have shown little improvement over the last 20 years. Communication is a practical skill that can be learned in theory from the literature or educational programs, but putting theory to practice in the clinical setting is far more problematic. Nurses need to be aware of their own communication skills by listening to themselves and learning from their mistakes. Only with this practice will skills improve. Communication can make or mar a person's illness experience. It is time for nurses to take effective communication seriously and actively accept personal responsibility for their actions because there is clear evidence showing that good communication makes a difference for patients and their families.

Communication↗
PubMed1999

A longitudinal evaluation of a communication skills programme.

Communication is an essential component of palliative care, but patients and their families are often dissatisfied with their interactions with health professionals. Communication difficulties are also a recognized stress factor among health professionals. Education and training, however, are said to improve communication skills. A communication skills training programme for 110 nurses has demonstrated statistically significant improvements in the nurses' skills, but no long-term effect was evaluated. This paper presents the results of the long-term follow-up study. Of the 110 nurses contacted, 20% refused to participate, 45% agreed and 35% did not respond; 33 nurses returned usable data. The mean length of time since completing the original study was 2.5 years. Since completion of the original course there was no statistically significant deterioration or improvement in eight of the nine areas of assessment skills evaluated. In the area of psychological assessment there was a statistically significant improvement, and overall the nurses maintained their skills and improved in this area. The results suggest that over time the nurses became more confident in the emotional areas of care as a result of the training. The two key elements of the training were audio-tape recordings and feedback, which raised self-awareness, and experiential workshops covering ways of handling difficult situations. Whether a similar training effect could be achieved by a short 3-5 day course on communication skills needs addressing, because the integrated training skills course evaluated here is costly. Preliminary evidence suggests that the 3-5-day course may not be as effective, so the increased costs associated with the integrated training skills course may be wisely spent if it improves the quality of nurse-patient interaction as evidence here suggests.

Adult↗
PubMed1999

An evaluation of aromatherapy massage in palliative care.

The use of complementary therapies, such as massage and aromatherapy massage, is rising in popularity among patients and healthcare professionals. They are increasingly being used to improve the quality of life of patients, but there is little evidence of their efficacy. This study assessed the effects of massage and aromatherapy massage on cancer patients in a palliative care setting. We studied 103 patients, who were randomly allocated to receive massage using a carrier oil (massage) or massage using a carrier oil plus the Roman chamomile essential oil (aromatherapy massage). Outcome measurements included the Rotterdam Symptom Checklist (RSCL), the State-Trait Anxiety Inventory (STAI) and a semi-structured questionnaire, administered 2 weeks postmassage, to explore patients' perceptions of massage. There was a statistically significant reduction in anxiety after each massage on the STAI (P < 0.001), and improved scores on the RSCL: psychological (P < 0.001), quality of life (P < 0.01), severe physical (P < 0.05), and severe psychological (P < 0.05) subscales for the combined aromatherapy and massage group. The aromatherapy group's scores improved on all RSCL subscales at the 1% level of significance or better, except for severely restricted activities. The massage group's scores improved on four RSCL subscales but these improvements did not reach statistical significance. Massage with or without essential oils appears to reduce levels of anxiety. The addition of an essential oil seems to enhance the effect of massage and to improve physical and psychological symptoms, as well as overall quality of life.

Adult↗