Pager messages as self reminders: A case study of their use in memory impairment

Each year many people suffer an accident or illness which leaves them with a permanent memory impairment. As a result they will fail to remember to do things, making it difficult for them to maintain employment or independent leisure activities. Conventional memory aids offer little assistance because their use depends on relatively normal memory functioning. A system designed specifically for memory-impaired people has been developed recently in the USA, however. NeuroPage uses a combination of computing and telecommunications to store and transmit reminders to a pager worn by the user. The system is designed to place minimal demands on memory. This paper presents a case study evaluation of NeuroPage in use by a young man with a severe memory impairment. The pager messages led to a marked increase in the probability that he would carry out his intended tasks. Issues of usability and acceptability of the system to the user and his family are also reported. A number of possible developments to the system are considered, including the incorporation of artificial intelligence and context-sensitivity. Broader issues in the design of memory aids for people with and without memory impairments are also considered, as well as the potential role of memory-impaired people in the design of technology for their own use.     

A multicenter study to improve emergency medicine residents' recognition of intracranial emergencies on computed tomography

STUDY OBJECTIVE: Cranial computed tomography (CT) has assumed a critical role in the practice of emergency medicine for the evaluation of intracranial emergencies. Several recent studies have documented a deficiency in the emergency physician's ability to interpret these studies. The purpose of this study was to quantify the baseline ability of emergency medicine residents to interpret cranial CTs, and to test a novel method of cranial CT interpretation designed for the emergency physician in training. METHODS: A standardized pretest was administered to assess baseline ability to interpret CT scans. A standardized posttest was given 3 months after the course. Each test consisted of 12 CT scans with a short accompanying history. All scans were validated by 3 expert reviewers for difficulty and diagnosis. A 2-hour course based on the mnemonic "Blood Can Be Very Bad" was then administered. "Blood" reminds the examiner to search for blood, "Can" prompts the examiner to identify 4 key cisterns, "Be" denotes the need to examine the brain, "Very" prompts a review of the 4 ventricles, and finally "Bad" reminds the examiner to evaluate the bones of the cranium. RESULTS: Eighty-three residents at 5 institutions were initially examined. The mean percentage correct before the course was 60% (95% confidence interval [CI] 58%-64%) on the standardized pretest. At retesting 3 months after the course, the accuracy rate increased to 78% (n=61, 95% CI 75%-81%, P<.001 paired t test). CONCLUSION: Emergency medicine residents are deficient in their ability to interpret cranial CT scans. A novel educational course was demonstrated to significantly improve this ability.     

Comparison of NIST and manufacturer calibrations of 90Sr+90Y ophthalmic applicators

Since the resumption of the NIST calibration service for 90Sr+90Y beta-particle ophthalmic applicators, 65 sources have been calibrated using the revised technique [C. G. Soares, Med. Phys. 18, 787-793 (1991)]. For 59 of these sources, the manufacturer's calibration results were available for comparison to the NIST calibration results. The 59 sources represent eight different manufacturers, only one of which is still selling new sources. Manufacturer calibration dates range from the present back to 1954. The results of the comparisons are present, broken down by both manufacturer and calibration date; there are interesting and significant trends in both, with average differences of 20% not uncommon. The obsolete unit, "roentgen-equivalent-beta" (reb), in which some of the manufacturer calibrations are expressed, is discussed, and a factor (0.00982 Gy reb-1) for its conversion to absorbed dose is suggested.     

Platelet adhesion to collagen activates a phosphoprotein complex of heat-shock proteins and protein phosphatase 1

Rapid activation of blood platelets is required for effective haemostasis, with shape change, aggregation, secretion of granule contents and cell adhesion occurring in seconds or even milliseconds. Signal-transduction events, evidenced by changes in protein phosphorylation and calcium levels, also take place in this time domain. We have now shown that platelet adhesion to collagen via the alpha 2 beta 1 integrin under arterial shear forces initiated the rapid dephosphorylation of a 67 kDa protein "band" which contained the 70 kDa constitutive heat-shock protein, hsc70. Immunoprecipitation with hsc70 antibodies revealed a large phosphoprotein complex in resting platelets and adhesion caused dissociation of the complex along with dephosphorylation of hsc70. The complex also contained the hsp90 heat-shock protein, protein phosphatase IC, alpha, delta and M subunits, and some 7-8 unidentified phosphoproteins. The data suggest that heat-shock proteins and protein phosphatases are actively involved in integrin-mediated platelet adhesion.     

Gaze-related activity of putative inhibitory burst neurons in the head-free cat

1. Previous studies in the cat have demonstrated that output neurons of the superior collicular as well as brain stem omnipause neurons have discharges that are best correlated, not with the trajectory of the eye in the head but, with the trajectory of the visual axis in space (gaze = eye-in-head + head-in-space) during rapid orienting coordinated eye and head movements. In this study, we describe the gaze-related activity of cat premotor "inhibitory burst neurons" (IBNs) identified on the basis of their position relative to the abducens nucleus. 2. The firing behavior of IBNs was studied during 1) saccades made with the head stationary, 2) active orienting combined eye-head gaze shifts, and 3) passive movements of the head on the body. IBN discharges were well correlated with the duration and amplitude of saccades made when the head was stationary. In both head-free paradigms, the behavior of cat IBNs differed from that of previously described primate "saccade bursters". The duration of their burst was better correlated with gaze than saccade duration, and the total number of spikes in a burst was well correlated with gaze amplitude and generally poorly correlated with saccade amplitude. The behavior of cat IBNs also differed from that of previously described primate "gaze bursters". The slope of the relationship between the total number of spikes and gaze amplitude observed during head-free gaze shifts was significantly lower than that observed during head-fixed saccades. 3. These studies suggest that cat IBNs do not fit into the categories of gaze-bursters or saccade-bursters that have been described in primate studies.(ABSTRACT TRUNCATED AT 250 WORDS)     

Viability in human heart valves prepared for grafting

Oral administration of synthetic D-penicillamine to rats induces alterations of the renal mesangium, apparently without involvement of immune mechanisms. Alterations of mitochondria, especially enlargement, were seen in the proximal tubular epithelium. These results are discussed in the light of recent findings in "penicillamine" nephritis and diseased human kidneys in general.     

Mineral mapping with HYperspectral Digital Imagery Collection Experiment (HYDICE) sensor data at Cuprite,Nevada, U.S.A.

The areal distributions of the minerals alunite, kaolinite, and calcite in an approximately 1.8km 2 area of the Cuprite mining district, Nevada, have been mapped by applying constrained energy minimization (CEM) to remotely sensed data from the HYperspectral Digital Imagery Collection Experiment (HYDICE) sensor, a 210 channel, 0.4 mum to 2.5 mum airborne hyperspectral imaging spectrometer. The image data analysed here have ground sample distances of approximately 3 m. CEM is a powerful and rapid technique for mineral mapping which requires only the spectrum of the mineral to be mapped and no prior knowledge of background constituents. Other spectral image processing techniques applied to the data produce results essentially identical to those of CEM and which agree with the mapping of Ashley and Abrams (1980).     

Volatile male-specific natural products of a coreid bug (Hemiptera: Heteroptera)

The large coreid bug,Pachylis laticornis (Hemiptera: Coreidae), feeds on several mimosaceous trees in Guanacaste, Costa Rica. In addition to the presumably defensive metathoracic exocrine glands that occur in both sexes of this species, the adult males also possess a ventral abdominal gland, opening midventrally in the 7–8th abdominal intersegmental membrane, that releases volatile compounds. Two esters, (E)-2-hexenyl tiglate and (E)-2-hexenyl (E)-2-hexenoate, account for over 90% of the total volatiles in the ventral abdominal gland secretion of males. (E)-2-Octenyl tiglate and (E)-2-hexenyl benzoate are present at low concentrations, as are at least three other unidentified compounds. The biological role for this fragrant male-specific exudate is unknown.