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The ‘H2S test’ is being advanced for microbiological water quality testing where conventional coliform based methods are impractical or too expensive. It involves ambient temperature incubation of water samples with nutrient formulated to generate hydrogen sulphide when ‘faecal’ bacteria are present. Recently a WHO review identified several concerns including the limited number of comparative studies, formulation variability, and false positives and negatives. In response we have compared the H2S test's ability to detect and quantify faecal contamination in an aquifer impacted by septic tank leachfields with measurements obtained concurrently using conventional bacterial indicators, coliphages, faecal sterol biomarkers, Cryptosporidium and Giardia. Like these other analytes, H2S testing detected a contamination gradient ranging from high (septic liquid) to moderate (exfiltration zones), to background (e.g. domestic bores), corresponding to indicator removal + dilution by factors >106. Presence/absence tests could not distinguish between heavily and slightly contaminated waters, whereas multi-tube testing (e.g. 10 × 10 mL arrays) did. It was concluded that while the WHO review concerns are justified, the H2S test performance shows promise in sanitary survey work, can be improved by employing an mpn approach and has potential to aid in the protection of source water and identifying contaminated groundwater.

Reliance on coliform monitoring of ground waters is slowly changing as is reflected in the proposed US EPA Ground Water Rule. In line with this we have investigated the use of an expanded range of faecal indicators and potential surrogate analytes within the Gwelup and Jandakot borefields in Perth, Western Australia. The aims of the study included comparing contamination in bores and surface waters in vulnerable locations, quantifying aquifer removal of microorganisms, trialing novel biochemical pollution indicators such as faecal sterols, assessing Escherichia coli as a measure of groundwater contamination and generating data for risk assessments. Sampling was undertaken of nine production bores, nine monitoring bores and four surface waters for 32 parameters comprising seven microbial indicators, 12 physico-chemical parameters and 13 biomarkers (including 8 faecal sterols and caffeine) at sampling stations potentially impacted by urban development. Concentrations of microbial indicators and biomarkers followed the pattern: basins >> monitoring bores >> production bores. Only one production bore sample contained bacterial indicators (0.1 enterococci.100 mL-1 on 1 occasion). Of the faecal biomarkers, coprostanol was generally at background levels. Cholesterol appeared to be a more sensitive measure of infiltration, but was also effectively removed. E. coli appeared to be a less sensitive indicator than enterococci. None of the physico-chemical parameters were useful surrogates. Overall apparent faecal microbial removal by aquifer filtration averaged >4-5 logs (not accounting for viruses). To maximise warning time and assay sensitivity it is suggested that enterococci be considered as the key bacterial indicator rather than E. coli and that different combinations of indicators and biomarkers be used to identify aquifer locations at risk, the presence of significant faecal material, and the likely presence of pathogens.

Instillation of respirable glass fibers to rat lungs served as an in vivo model for the detection and evaluation of differential local biological responses to particulate matter in the deep lung. Three compositions of vitreous glass, stonewool, and refractory fiber materials (MMVF 10, HT, and RCF1a) were harvested with surrounding lung tissues and examined both histologically and by physical/chemical assays to correlate the observed differential dissolution events with specific biological responses associated with each material. Specimens at 2-days, 7-days, 30-days and 90-days post-instillation were compared from at least three rats for each condition and for phosphate-buffered-saline controls. HT fiber surface and bulk chemistry uniquely allowed direct histochemical visualization of fiber degradation steps by Prussian Blue staining, while multiple attenuated internal reflection infrared spectroscopy and energy-dispersive X-ray analysis of unfixed, fresh lung lobe slice surfaces revealed the conc...

In the last decade we have seen the emergence of botulinum toxin (BTX) as a successful treatment of patients with neurogenic and idiopathic detrusor overactivity that are refractory to antimuscarinic medication. The success of BTX in this patient population has led to use BTX in patients with other causes of lower urinary tract symptoms such as benign prostatic hyperplasia (BPH) and urethral sphincter anomalies. Despite this success, the protocol for BTX injection has not yet been standardized. Various studies are on the way in order to determine the best injection protocol for bladder injection of BTX. The use of BTX in patients with BPH is in its early stages. Further large randomized controls trials in patients with BPH are needed to determine the efficacy of BTX in this patient population.

The 'H2S test' is being advanced for microbiological water quality testing where conventional coliform based methods are impractical or too expensive. It involves ambient temperature incubation of water samples with nutrient formulated to generate hydrogen sulphide when 'faecal' bacteria are present. Recently a WHO review identified several concerns including the limited number of comparative studies, formulation variability, and false positives and negatives. In response we have compared the H2S test's ability to detect and quantify faecal contamination in an aquifer impacted by septic tank leachfields with measurements obtained concurrently using conventional bacterial indicators, coliphages, faecal sterol biomarkers, Cryptosporidium and Giardia. Like these other analytes, H2S testing detected a contamination gradient ranging from high (septic liquid) to moderate (exfiltration zones), to background (e.g. domestic bores), corresponding to indicator removal + dilution by factors10(6). Presence/absence tests could not distinguish between heavily and slightly contaminated waters, whereas multi-tube testing (e.g. 10 x 10 mL arrays) did. It was concluded that while the WHO review concerns are justified, the H2S test performance shows promise in sanitary survey work, can be improved by employing an mpn approach and has potential to aid in the protection of source water and identifying contaminated groundwater.

We will describe an adaptive optics system developed for the 1 meter Nickel and 3 meter Shane telescopes at Lick Observatory. Observing wavelengths will be in the visible for the 1 meter telescope and in the near IR on the 3 meter. The adaptive optics system design is based on a 69 actuator continuous surface deformable mirror and a Hartmann wavefront sensor equipped with an intensified CCD framing camera. The system has been tested at the Cassegrain focus of the 1 meter telescope where the subaperture size is 12.5 cm. The wavefront control calculations are performed on a four processor single board computer controlled by a Unix-based system. We will describe the optical system and give details of the wavefront control system design. We will present predictions of the system performance and initial test results.

The architecture and major system components of the sodium-layer laser guide star system at LLNL will be described, and experimental results reported. The subsystems include the laser system, the beam delivery system including a pulse stretcher and beam pointing control, the beam director, and the telescope with its adaptive-optics package.

Recent results from the Laser Guide Star Project at Lawrence Livermore National Laboratory are presented. Photometry of the return signal has shown that the photon return is approximately 10 photons/cm2/ms at the pupil of the receiving telescope in agreement with a detailed model of the sodium interaction. Wavefronts of the laser guide star have also been measured with a Shack-Hartmann technique and power spectra have been shown to agree with those of nearby natural stars. Plans for closed loop demonstrations using the laser guide star at LLNL and nearby Lick Observatory are discussed.© (1993) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

We describe the design and the early results of a feasibility experiment for sodium-layer laser-guide-star adaptive optics. Copper-vapor-laser-pumped dye lasers from Lawrence Livermore National Laboratory’s Atomic Vapor Laser Isotope Separation program are used to create the guide star. The laser beam is projected upward from a beam director that is located ~5 m from a 0.5-m telescope and forms an irradiance spot ~2 m in diameter at the atmospheric-sodium layer (at an altitude of 95 km). The laser guide star is approximately fifth magnitude and is visible to the naked eye at the top of the Rayleigh-scattered laser beam. To date, we have made photometric measurements and open-loop wave-front-sensor measurements of the laser guide star. We give an overview of the experiment’s design and the laser systems, describe the experimental setup, show preliminary photometric and open-loop wave-front-sensor data on the guide star, and present predictions of closed-loop adaptive-optics performance based on these experimental data. The long-term goal of this effort is to develop laser guide stars and adaptive optics for use with large astronomical telescopes.

We describe a series of experiments to characterize the sodium-layer guide star that was formed with the high-power laser developed for the Lawrence Livermore National Laboratory Atomic Vapor Laser Isotope Separation program. An emission spot size of 3.0 m was measured, with an implied laser irradiance spot diameter of 2.0 m. The rms spot motion at the higher laser powers, with active beam-pointing control, was less than 0.5 arcsec and had little effect on the observed spot size under these conditions. We measured the resonant backscatter from the sodium layer as a function of laser power to obtain a saturation curve. With a transmitted power of 1100 W and an atmospheric transmission of 0.6, the irradiance from the guide star at the ground was 10 (photons/cm2)/ms, corresponding to a visual magnitude of 5.1. The implications for the performance of wave-front sensors with a laser guide star of this magnitude and resulting closed-loop adaptive-optics performance are discussed.

When injected i.v. into mice, the F10 subline of B16 melanoma cells produced significantly more lung tumours over a 3-week period than cells of the F101.r-6 subline. However, in animals bearing intramuscular tumours produced by these sublines, the high pulmonary-colonization potential of the F10 cells was not realized, and no significant differences in natural pulmonary metastasis formation were observed in animals with untreated primary cancers, even when they progressed to the moribund state. Massage of i.m. tumours derived from the two sublines produced no change in metastasis and no changes in the numbers of cancer cells in the blood detectable by bioassay. In contrast, massage increased metastasis from tumours derived from an invasive BL6 subline and B16 wild-type cells and, in the case of the wild-type, the numbers of circulating cancer cells. In vitro experiments show that blood cells from non-tumour-bearing animals are toxic to both sublines; but less to F10 than to F101.r-6. In addition, after i.v. injection of radiolabelled cells, more of the F10 subline were retained in the lungs of recipients than the F101.r-6. In spite of these apparent metastatic advantages of the F10 subline following intravasation, the incidence of natural metastases from i.m. F10 and F101.r-6 tumours was similar, suggesting that substantially fewer F10 than F101.r-6 cells gained access to the circulation. Thus, the higher colonization potential of the F10 cells was not matched by its intravasation potential, since metastatic efficiency is determined by the least efficient step in the metastatic process.

The accuracy of five gravity-feed infusion-control devices was compared using a gravimetric method. Two nonvolumetric drop-counting devices (IVAC 230 and, IMED 350) and three volumetric devices (Quest/Cutter Infusor, Anatros Rateminder, and IVAC 260) were compared at four different flow rates (10, 40, 125, 250 ml/hr) using four different solutions and two head heights (30 and 100 cm). The mean error rates for the IVAC 230 and the IVAC 260 devices were consistently high and negative (-6.32 and -12.60%, respectively). The mean error rates for the IMED, Anatros, and Quest/Cutter devices were 2.2, 1.8, and 0.7%, respectively. Conversion charts must be used to account for variation in drop size when different solutions and flow rates are used in the IVAC 230 and IMED 350 devices. At the low flow rates, the 60-drop/ml sets were more accurate than the 20-drop/ml sets. Of the volumetric devices, the Quest/Cutter Infusor and the Anatros Rateminder were more accurate than the IVAC 260. The Quest/Cutter Infusor was the most accurate of all controllers tested. For volumetric devices that use drop-counting technology, selecting an internal fluid code on the basis of solution ingredients is still necessary. For the new volumetric devices, conversion charts and fluid code selection are not necessary to achieve a high level of accuracy.

The effects of d-amphetamine on temporal discrimination in the rat were studied. Rats were trained on a two-manipulandum task involving the discrimination between two tones differing only in duration. d-Amphetamine (0.1 - 1.6 mg/kg) disrupted performance on this task, although not in an obvious dose-related manner. Lever biases were enhanced by the drug, but inconsistenly among rats. Enhanced lever bias did not necessarily correlate with deterioration of performance. The drug lengthened both response latency and the performance of terminal components of the operant chain. However the characteristic pattern of response latencies produced by the two tones was not altered significantly by the drug. The results are discussed in terms of whether the drug disrupts discrimination performance by a direct effect on processes of temporal discrimination or indirectly, by its other effects on behavior.

Summary There is a high correlation between behaviour problems, and lack of receptive and expressive language communication. Multiply handicapped children, with varying degrees of physical, mental, emotional, and sensory handicaps, in addition to a communication deficit, can learn a sign language system. Progress in communication through the sign language also results in substantial emotional and behavioural improvements. This paper presents two case studies of such children, and describes in detail the 7 year programme used to develop language through the Paget—Gorman sign system, with a profoundly deaf, subnormal, athetoid, disturbed boy.

Summary Seven subnormal spastic children aged 15–16 years, who had the additional problem of profuse dribbling, were trained to associate an auditory cue, from a small box pinned to their clothes, with swallowing. A significant reduction in dribble rate was obtained for all children within the first week. This method of dribble control has two advantages: it requires very little professional time, and the child's ability to control his dribbling is emphasized from the beginning.

Avoidance or elimination of the major offending food items or indoor problematic allergens can help many patients with allergy-related otologic problems. Other patients can be helped by immunotherapy. For symptom relief, the patients' total exposure must be less than their symptom threshold level. The bottom line must be an effort to find the easiest, simplest, safest, and most economical method to relieve symptoms. By eliminating the cause of the medical problem, it is often possible to obviate not only the need for surgery, but also the necessity to mask the patients' symptoms with medications.