Life cycle of Ixodes minor (Acari: Ixodidae) in the laboratory

OBJECTIVE: It is commonly believed that the full moon exerts an influence on violence and aggression in psychiatric settings. The literature to date is contentious. This study used a robust methodology to examine the hypothesis that there was an increased frequency of violent and aggressive behaviour among hospitalised psychiatric clients at the time of the full moon. METHOD: Prospective data were collected in five inpatient psychiatric settings across the Northern Sydney Area Health Service. Morrison's hierarchy of violence and aggression was used to rate behaviour. Lunar phases were clearly defined and Poisson regression used to examine relationships between lunar phase and violence. Extraneous temporal variation was considered. RESULTS: No significant relationship was found between total violence and aggression or level of violence and aggression and any phase of the moon. CONCLUSION: Future research could profitably examine the implications of a belief in the lunar effect among health workers in the face of evidence that no relationship exists between violence, aggression and the lunar cycle.     

Biomagnetic neurosensors. 2. Magnetically stimulated sensors

We report the generation of action potentials in crayfish neurons by magnetic pulses for analytical purposes. A copper wire toroid, containing a ferrite core, was placed around the nerve bundle, and square wave current pulses were sent through the wire to generate a magnetic field. The magnetic field generated an action potential in the neuron that was detected downfield by a pickup microelectrode. The biosensor was used to detect local anesthetics by monitoring the time necessary for complete blockage of the action potential. Techniques for improving the efficiency and lifetimes of neural biosensors are discussed.     

Performance characteristics of a whole-body PET scanner

METHODS: This study characterizes the performance of a newly developed whole-body PET scanner (Advance, General Electric Medical Systems, Milwaukee, WI). The scanner consists of 12,096 bismuth germinate crystals (4.0 mm transaxial by 8.1 mm axial by 30 mm radial) in 18 rings, giving 35 two-dimensional image planes through an axial field of view of 15.2 cm. The rings are separated by retractable tungsten septa. Intrinsic spatial resolution, scatter fraction, sensitivity, high count rate performance and image quality are evaluated. RESULTS: Transaxial resolution (in FWHM) is 3.8 mm at the center and increases to 5.0 mm tangential and 7.3 mm radial at R = 20 cm. Average axial resolution decreases from 4.0 mm FWHM at the center to 6.6 mm at R = 20 cm. Scatter fraction is 9.4% and 10.2% for direct and cross slices, respectively. With septa out, the average scatter fraction is 34%. Total system sensitivity for true events (in kcps/(microCi/cc)) is 223 with septa in and 1200 with septa out. Dead-time losses of 50% correspond to a radioactivity concentration of 4.9 (0.81) microCi/cc and a true event count rate of 489 (480) kcps with septa in (out). Noise-equivalent count rate (NECR) for the system as a whole shows a maximum of 261 (159) kcps at a radioactivity concentration of 4.1 (0.65) microCi/cc with septa in (out). NECR is insensitive to changes in lower gamma-energy discrimination between 250-350 keV. CONCLUSIONS: The results show the performance of the newly designed PET scanner to be well suited for clinical and research applications.     

Surgical treatment and outcome in patients with a hepatocellular carcinoma greater than 10 cm in diameter

BACKGROUND: Hepatocellular carcinoma (HCC) over 10 cm in diameter at the time of diagnosis continues to account for a number of patients undergoing hepatic resection. This study evaluated the clinicopathological features and outcome following surgery for large HCC. METHODS: Forty patients with a large HCC (greater than 10 cm) (group 1) resected between 1991 and 1996 were studied retrospectively. They were compared with 245 patients who had smaller HCCs (10 cm or less) (group 2). RESULTS: No patient in group 1 had hepatitis C infection compared with 22.9 per cent in group 2 (P=0.001). Patients in group 1 were significantly younger, had higher alpha-fetoprotein levels (16750 versus 1864 ng/ml; P < 0.001), better liver function, a higher incidence of multiple tumours (27 of 40 versus 42.0 per cent; P=0.003) and venous invasion (35 of 40 versus 52.2 per cent; P < 0.001), and underwent more major resections (37 of 40 versus 26.5 per cent; P < 0.001) than those in group 2. Morbidity and mortality rates and hospital stay were comparable in the two groups. For group 1, the 1-, 3- and 5-year disease-free survival rates were 42, 30 and 28 per cent respectively. Multiple tumours, venous invasion and impaired liver function were factors associated with recurrence. CONCLUSION: Large HCC had specific clinicopathological features. In selected patients, resection is safe and offers the chance of long-term disease-free survival.     

The small-cell variant of mycosis fungoides. A clinicopathological and quantitative electron microscopic study on 14 patients

Small-cell variants of Sézary syndrome and mycosis fungoides (MF) have been described. However, in these studies the nuclear area of the small-cell variant of MF (SC-MF) as compared to histological classical MF (CL-MF) was not characterized objectively by quantitative electron microscopy. In a 14-year follow-up period, of a total of 76 patch/plaque stage MF patients seen in the Department of Dermatology of the University Hospital Utrecht, 14 (18%) had an infiltrate composed of atypical lymphocytes characterized by a distinctly smaller cell diameter and smaller, hyperchromatic, deeply indented nuclei as compared to the usual cell type of MF. The aim of the investigation was to confirm this observation objectively using quantitative electron microscopy (morphometry) and to define SC-MF as compared to CL-MF. The study was performed on the 14 patients with SC-MF, and 10 patients with clinical and histological CL-MF and 4 patients with chronic eczema. Electron micrographs of sections obtained from each biopsy were analysed by computer to produce the following data: a nuclear contour index (NCI), the mean nuclear area (MNA), the mean nuclear area of the cells above the 75th percentile (P75NA) and the percentage of cells larger than 30 microm2. The values of MNA differed significantly between patients with SC-MF and those with CL-MF (17.6 vs 23.2 microm2; P = 0.02), as did the values of P75NA (20.7 vs 27.9 microm2; P = 0.01). The NCI of the SC-MF and CL-MF patients were similar. These results are consistent with our observations that SC-MF does indeed exist.     

The invisible profession

The job of a manager continues to be one of achieving outcomes through other people. However, in the current work environment, managers are finding that while their scope of responsibility is expanding, the traditional power base used to excourage high performance is shrinking. There are limited rewards a manager can use to gain commitment from their staff. Even if some of those rewards are available, many of the new employees do not see them as motivators. Employees come to the workplace with a different set of expectations. There seems to be a mismatch between the traditional management approach to getting the best from the worker and what the worker wants from their manager. In as much as the workplace and the worker are changing so too must manager's approach to "getting the job done."