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Introduction: Patient accessible electronic health records can be used to inform and empower patients. However, their use may require complementary information seeking since they can be difficult to interpret. So far, relatively little is known of the information seeking that takes place in connection to health record use, and especially the way it varies in different age groups. A better understanding of patients’ preferences of where and how to find explanatory information provides valuable input for the development of health information provision and counselling services. Method: The analysis is based on the results of a national survey of Swedish individuals (N=1,411) who had used a national patient accessible electronic health record system (Journalen). Analysis: The data were analysed in SPSS 24.0 using Kruskal-Wallis tests for detecting group-wise differences and Jonckheere-Terpstra tests for discovering age-related trends in the data. Findings: Older patients were more likely to use a telephone and younger patients to use social contacts to ask for clarification. Generally, older adults born between 1946–1960 appear as passive information seekers. Conclusion: Age groups differ in their preferences on how to seek clarification, which underlines the importance of a better understanding of individual differences in delivering not only technically but also intellectually accessible health information. Calling by telephone could be a habit of present older generations whereas, to a degree, searching information online could be a comparable habit of current younger generations.

To address the research gap on age-based differences in health information literacy (HIL), we investigated how younger (born 1960–) and older adults (1946–1960), and elderly citizens (–1945) differed from each other by their HIL competencies. Data were collected with an online survey of patients using the Swedish national electronic health record system. Altogether, 2,587 users responded. One-way ANOVA with post hoc tests revealed several differences between the groups: younger adults were less likely to value health information than older adults; older adults and elderly were least likely to compare information from multiple sources and had trouble in determining health information needs; older adults were most likely to have trouble understanding health terminology and the elderly to have difficulties in understanding medicinal package labels. The study shows that HIL is not necessarily improving or declining but adapting to challenges of advanced age.

Methods of recycling unplasticized polyvinyl chloride (uPVC) window frame waste were investigated. The quality of untreated granular waste was compared to that of waste treated by a range of contaminant removal processes including melt filtration and dissolution. Processability of each recyclate was evaluated by using a highly instrumented single screw extruder that enabled melt viscosity and process variation to be monitored in real time. Product quality measurements such as mechanical properties and surface defects were made on extruded strip, and the nature of the stabilizers present was determined. The mechanical properties of recyclates were found to be comparable to or better than those of virgin material in all cases and conformed to industry standards for window profile. Contaminant removal stages significantly reduced the amount of large surface defects detected in extrudate. Processability was comparable to that of virgin compounds, but melt viscosity varied among different batches of recyclate, depending on the source and composition of the original PVC formulation. J. VINYL ADDIT. TECHNOL., 11:119–126, 2005. © 2005 Society of Plastics Engineers

The effect of three chemicals with different mechanisms of action (3,4-dichloroaniline, fenoxycarb, and chlorpyrifos) on the life history response of the cladoceran Ceriodaphnia cf. dubia was examined under both limited (3×10 4 cells/mL) and abundant (15×10 4 cells/mL) food conditions. Toxicity tests were conducted at both food concentrations simultaneously for each chemical, and cladocerans were examined daily from less than 24 h old until their death. A range of life history parameters were calculated, including mean brood sizes, survival, net reproductive rate, and population growth rate. The toxicity of 3,4-dichloroaniline was not significantly affected by food concentration. However, limited food significantly decreased the toxicity of fenoxycarb, and significantly increased the toxicity of chlorpyrifos. The effect of food concentration on toxicity appears to depend on the mechanism by which the chemical exerts its toxicity and on food–chemical interactions. Possible mechanisms for the different effects of food concentration on toxicity are discussed.

The combined effects of food concentration and population density on some life history characteristics of the small-bodied cladoceran Ceriodaphnia cf. dubia were studied by examining animals maintained at densities of 100–3000 individuals l−1 for 8 days that had been fed either abundant (30×104 algal cells ml−1 ind−1) or limited (5×104 algal cells ml−1 ind−1) food. The amount of food provided significantly (p

One of the acknowledged limitations ofconventional toxicity tests is their inabilityto evaluate the impact of toxicants onsubsequent generations. Given their relativelyshort lifespan, cladocerans in the field may beexposed to toxicants for several generations.However, it is unclear what effect such anexposure regime could have on the cladoceranfitness after removal of the toxicant. Thispaper aimed to determine the offspring fitnessof juveniles produced by adult Ceriodaphnia cf. dubia exposed toresidual levels of 3,4-dichloroaniline overfour generations. Mass cultures of Ceriodaphnia cf. dubia were maintainedfor several generations in variousconcentrations of 3,4-dichoroaniline (0, 2.5,5, 10, 15 and 20 µg/L). The mass cultureswere re-established every generation using4th brood neonates 0.05) changes inreproduction due to 3,4-dichloroaniline wereobserved for the F2 and F3 offspring. However,F4 offspring of mothers exposed to all3,4-dichloroaniline concentrations showedsignificantly (p < 0.05) increasedreproduction compared to the controls. Possibleexplanations for the varying influence ofmaternal 3,4-dichloroaniline exposure on thereproductive output of the offspring arediscussed.

The toxicity of chemicals with different mechanisms of action (3,4-dichloroaniline, fenoxycarb, and chlorpyrifos) to the cladoceran Ceriodaphnia cf. dubia was examined in the presence and absence of chemicals exuded by fish, termed fish kairomones. A range of life-history traits were examined, including mean brood sizes, survival, net reproductive rate (Ro) and population growth rate (r). Cladocerans exposed to 3,4-dichloroaniline showed similar sensitivities in the presence and absence of fish kairomones with respect to all of the life-history traits examined. The presence of fish kairomones reduced the sensitivity of cladocerans to fenoxycarb with respect to mean brood sizes and r but increased their sensitivity in terms of Ro. The presence of fish kairomones increased the sensitivity of cladocerans to chlorpyrifos with respect to survival, r, Ro, and mean brood sizes. The general trends observed were similar to those shown when C. cf. dubia was exposed to these chemicals under low food conditions, and it is suggested that the effects of fish kairomones on toxicity may be attributed to the reduction in feeding rates observed when C. cf. dubia is exposed to fish kairomones.

This study examined the effect of water that previously contained fish on several life history traits of the small-bodied cladoceran Ceriodaphnia cf. dubia. Four fish density treatments were tested (i.e. 16.7, 5.9, 2 and 0.9 l fish‐1). A significant (P 0.05) cladoceran survival. The observed effects are ascribed to the presence of unidentified substances in the water that previously contained fish. These substances are thought to be ‘fish kairomones’. While life history changes occur in the laboratory, it remains unclear whether similar changes would occur in the field.

The effect of five different food concentrations on the life history of Ceriodaphnia cf. dubia was examined by following cohorts of 25 individuals from

Injection moulding studies are reported, during which in process measurements have been used to monitor batch to batch variation of several production grade polymers. Three materials were studied: a polyamide 6, a polyacetal, and a flexible poly(vinyl chloride), all of which were commercial injection moulding polymers supplied by industrial collaborators. Instrumented high precision electric and servohydraulic moulding machines were used to mould parts in house from a number of different material batches. Moulding conditions were kept constant throughout and several process variables were monitored during injection, including melt pressure, melt temperature, and viscosity index –a specific pressure integral calculated from primary injection. Part weights were measured to provide an indication of part quality. Results showed that in each case, variations between batches produced a measurable effect on part quality. These variations were detected by in process measurements, particularly by viscosit...

In-process and off-line rheometry studies are reported for compounds based on Mg(OH)2 filled low density polyethylene, some of which were first subjected to a range of strain histories in typical compounding operations. In the study reported here, the compounds were processed using an instrumented, computer monitored single screw extruder in the IRC laboratories, fitted with in line rheometers (ILR). In initial experiments a four sensor ILR slit die was used for the in-process shear rheometry, and a Rosand RH7 twin bore capillary rheometer for off-line shear and entry pressure measurements. Off line and in-line results are compared, showing good agreement for shear. Estimates have been obtained for the sensitivity to filler loading of the off line rheometer (shear flow and entry pressure measurements), and the 4 sensor ILR (shear flow measurements), which indicate that the ILR offers similar resolution of filler level to the off line rheometer at the higher loadings, although the ILR appears to have much lower sensitivity at higher shear rates at lower loadings, an effect which appears to be related to processing effects on the rheology of the compound rather than the measurement ability of the ILR. The ILR was also able to discriminate between samples with differing processing histories. Results from a six-sensor ILR die have shown good agreement in shear flow measurements, and have added the ability to measure entry pressures, which are compared with off-line measurements.

A highly sensitive multichannel SQUID gradiometer, optimized uniquely for spatial resolution, was used to map in two dimensions the magnetic field perturbations from circular holes and thin slots in conducting plates and strips, respectively. Holes as small as 0.75 mm radius in electrically conducting plates were measured directly using a single channel. Edge slots as short as 0.5 mm long in conducting strips were detected, using a multiple-channel measurement method which eliminated the effects from the edge of the strip and the current leads. Clear magnetic signatures from these simulated cracks were measured using low current densities. Numerical computations of the theoretical field distributions are presented which confirm the experimental results. Calculations indicate that much smaller defects should be detectable with an optimization of test parameters.

Cross-sectional and 36-month prospective analyses of the relationships among anomie and both alcohol abuse and alcohol consumption patterns provided little support that anomie was directly associated with ethanol ingestion patterns in a sample of 302 male air traffic controllers. This lack of association was observed for self-reported alcohol consumption, interview-established alcohol abuse and biochemical markers of alcohol intake. In addition, anomie was not predictive of change in alcohol use/abuse over 36 months, controlling for baseline levels of alcohol use and abuse and for relevant demographic factors. Measurement of anomie and alcohol use/abuse, the relative importance of anomie in various socioeconomic groups and issues related to prospective research on this topic are discussed.

Microfilamentary composites of continuous Nb fibers in Cu matrices were tested for superconducting transport properties after heat treatments at 200–900 °C. The critical current density at applied magnetic field was reduced dramatically as the heat treatment temperature was increased. The scaling relations describing the critical current as a function of applied field shifted from conventional (1−h)2 scaling to higher‐order relations as the heat treatment history was varied. Critical temperature transitions were abnormally broad in the fine‐filament composites examined. The upper critical fields and transition temperatures approached bulk values after severe heat treatment.

Many anthropogenic pollutants are present in aquatic systems for extended periods of time. Populations in the field may be exposed to toxicants for several generations, which may affect their sensitivity to toxicants. Ceriodaphnia cf. dubia mass cultures were maintained for four generations in various concentrations of 3,4-dichoroaniline (0, 2.5, 5, 10, and 15μg/L) and were reestablished every generation using fourth-brood neonates. Each generation, chronic toxicity tests were initiated using fourth-brood neonates from each mass culture treatment. Significantly (P

The toxicity of chemicals with different mechanisms of action (3,4-dichloroaniline, fenoxycarb, and chlorpyrifos) to the cladoceran Ceriodaphnia cf. dubia was examined in the presence and absence of chemicals exuded by fish, termed fish kairomones. A range of life-history traits were examined, including mean brood sizes, survival, net reproductive rate (Ro) and population growth rate (r). Cladocerans exposed to 3,4-dichloroaniline showed similar sensitivities in the presence and absence of fish kairomones with respect to all of the life-history traits examined. The presence of fish kairomones reduced the sensitivity of cladocerans to fenoxycarb with respect to mean brood sizes and r but increased their sensitivity in terms of Ro. The presence of fish kairomones increased the sensitivity of cladocerans to chlorpyrifos with respect to survival, r, Ro, and mean brood sizes. The general trends observed were similar to those shown when C. cf. dubia was exposed to these chemicals under low food conditions, and it is suggested that the effects of fish kairomones on toxicity may be attributed to the reduction in feeding rates observed when C. cf. dubia is exposed to fish kairomones.

We analyzed data from two national surveys to estimate the short-term work disability associated with thirty-day major depression. Depressed workers were found to have between 1.5 and 3.2 more short-term work-disability days in a thirty-day period than other workers had, with a salary-equivalent productivity loss averaging between $182 and $395. These workplace costs are nearly as large as the direct costs of successful depression treatment, which suggests that encouraging depressed workers to obtain treatment might be cost-effective for some employers.

The toxicity of eleven nonpolar narcotic chemicals to the cladoceran Ceriodaphnia cf. dubia was determined. C. cf. dubia was found to be approximately four times more sensitive to these narcotic chemicals than Daphnia magna tested under virtually identical conditions. The toxicity data were also used to develop and validate quantitative structure-activity relationships (QSARs) using a range of physicochemical properties of the chemicals. The three best QSARs, based on octanol-water partition coefficients and two lipid-water partition coefficients, were able to explain 98% of the variation in toxicity. The mean absolute percentage errors between the predicted and experimental EC50 values for these three QSARs were 17.3%, 20.6%, 24.6%. Neither the critical concentration (CC) nor the critical volume (CV) hypotheses validly modeled the toxicity data when octanol-water and triolein-water partition coefficients were used although the CV hypothesis was the better of the two. When a phospholipid-water partition coefficient was used the CV hypothesis was valid. The mean toxic membrane volume fraction of 0.48 x 10(-2) m3/m3 derived in this study agreed with published values for nonpolar narcotics and supports the use of this property to determine the mode of action of chemicals.

The oxidation level of ultrahigh molecular weight polyethylene specimens sterilized by gamma irradiation in either air or Ar gas was compared with that of unsterilized and ethylene oxide sterilized ultrahigh molecular weight polyethylene. The fatigue strength of ultrahigh molecular weight polyethylene specimens sterilized by gamma irradiation in air was compared with that of unsterilized and ethylene oxide sterilized ultrahigh molecular weight polyethylene. At the specimen surface, oxidation was highest for ultrahigh molecular weight polyethylene gamma irradiated in air, lower for ultrahigh molecular weight polyethylene gamma irradiated in Ar gas, and absent in unsterilized and ethylene oxide sterilized ultrahigh molecular weight polyethylene. At a depth of 3.5 mm below the specimen surface, oxidation levels were equivalent for ultrahigh molecular weight polyethylene gamma irradiated in either air or Ar gas whereas unsterilized and ethylene oxide sterilized specimens were again unoxidized. Thus, even in an inert atmosphere, oxidative degradation of gamma irradiated ultrahigh molecular weight polyethylene occurs. The 10 million cycle fatigue strength was similar for unsterilized and ethylene oxide sterilized ultrahigh molecular weight polyethylene whereas the fatigue strength of gamma irradiated in air ultrahigh molecular weight polyethylene was lower. Results of this study show that ethylene oxide gas does not degrade ultrahigh molecular weight polyethylene whereas gamma radiation in air causes changes in the polymer that adversely affect its mechanical properties. Ethylene oxide gas is a viable alternative to gamma radiation in air that avoids oxidation and fatigue strength degradation known to accompany irradiation of ultrahigh molecular weight polyethylene polymer bearing surfaces in total joint implants.

Severe injury is frequently complicated by sepsis and organ failure. Activated neutrophils adherent to inflamed endothelia have been implicated in the pathogenesis of these complications. Identification of high-risk patients to target immunomodulatory therapy, however, remains an elusive goal. We postulated that (1) patients at risk for sepsis and organ failure could be identified by measuring shed selectin adhesions molecules as a marker of endothelial activation after injury and reperfusion, and (2) these elevated selectin levels would correlate with injury severity, shock, major complications, and mortality. Methods : Blood samples were drawn from 50 patients with multiple trauma every 2 hours after admission for the first 24 hours, and every 6 hours for the subsequent 24 hours, and assayed for levels of shed E- and P-selectin. Patients were then stratified according to Injury Severity Score (ISS), presence or absence of shock, presence or absence of organ failure and/or infectious complications, and finally, death versus survival. Results : Trauma patients who had ISS < 30, who did not develop shock, sepsis, or organ dysfunction, had minimal increase in circulating E- and P-selectin over admission levels. In patients who subsequently developed infectious complications, organ dysfunction, or both, or subsequently went on to die, elevated levels of E-selectin levels were evident by 36 hours, and in some cases, earlier. Differences between nonsurvivors and survivors was statistically significant. There was also a trend toward increased levels of P-selectin in the same group of patients, although these differences were not significant. There was no differentiation in either of the two selectins when patients were stratified according to ISS or presence of shock. Conclusion : A subset of major trauma patients manifest increased levels of circulating E-selectin adhesion molecules after resuscitation. These patients seem to be at increased risk of death and possibly at risk for infectious complications and organ failure. Selectin blockade is a potential new immunomodulatory strategy in this subgroup of patients.

In bronchoalveolar lavage (BAL) of human immunodeficiency virus (HIV)-infected patients with Pneumocystis carinii pneumonia and in lungs of glucocorticoid-immunosuppressed rats infected with P. carinii, surfactant phospholipid levels are reduced. However, levels of the surfactant-associated protein-A (SP-A) in BAL are 4-5 times higher than normal in patients with P. carinii pneumonia. In this study, we examined the effects of glucocorticoid immunosuppression and P. carinii infection on SP-A messenger ribonucleic acid (mRNA) and protein levels in rat lungs. Rats were immunosuppressed by adding dexamethasone to their drinking water and were infected with P. carinii by intratracheal instillation of the organism. SP-A was measured by enzyme-linked immunosorbent assay (ELISA) and SP-A mRNA by hybridization of Northern blots with an SP-A complementary deoxyribonucleic acid (cDNA) probe. There was a severalfold increase in SP-A protein and mRNA levels in uninfected glucocorticoid-treated rats. However, contrary to what has been reported with the surfactant-associated lipids, SP-A mRNA and protein levels in P. carinii-infected animals were significantly higher than those found in the uninfected, immunosuppressed animals. Our results demonstrate that SP-A increases, probably as a result of elevated mRNA levels, in immunosuppressed rats with P. carinii infection and are consistent with our findings in HIV-positive patients with P. carinii pneumonia.

Which personal characteristics are used in selecting astronauts? We decided to examine this question using National Aeronautics and Space Administration (NASA) archival data collected on 2288 applicants. Undergraduate grade point average, graduate grade point average, and several facets of aviation experience were the best predictors of who was interviewed and then selected to be an astronaut. Adjustments were made to insure that a sufficient number of women and minority group members were selected, while still maintaining high selection standards. The selection process seems well-designed, and follows explicit NASA guidelines. We suggest simplifying the selection process by using a single discriminant function as an interview and/or selection criterion.

We add a slow hyperpolarization-activated inward current I H = g H m H ( v - v H) to our previous model of rebound bursting (Hindmarsh & Rose Phil. Trans. R. Soc. Lond . B 346, 129—150 (1994 a )) to give a fourdimensional physiological model, and a corresponding four-dimensional model of the model. The physiological model generates periodic ‘bursts of bursts’ or ‘spindles’ resembling those recorded experimentally in thalamocortical (TC) neurons. The model of the model is simplified to a two-dimensional system having a limit cycle which corresponds to the slow spindle oscillation of the physiological model. Analysis of the stability of this two-dimensional model allows us to divide the parameter space of the slope (y mH ) and shift (0 mH ) parameters of mH oo( v ) into regions in which the model generates spindles or continuous bursting. This enables us to determine the parameter values required for spindling in the physiological model and to explain the experimentally observed effects of noradrenaline. Next we examine whether a cell at a stable equilibrium point can be driven into spindling by applying a sinusoidal input at the resonant frequency. This is done by averaging the equations for the driven model of the model. Analysis of the stability of these averaged equations shows how the regions of the (0 mH ,y mH ) parameter space change when the system is driven by a sinusoidal input. This enables us to choose parameter values for a physiological model of a driven spindle. We show that if the physiological model is modified to include a voltage-dependent time constant for mH , spindles, similar to those of TC cells, can be obtained with a small Ca 2+ -activated K+ current. Finally our knowledge of the form of the bifurcation diagram and the conditions for resonance leads to a new suggestion for the roles of GABA A and GABA B inhibitory postsynaptic potentials when TC cells are driven into spindling by neurons of the nucleus reticularis thalami.

In this paper we begin by simplifying our previous model of a thalamic neuron (Rose & Hindmarsh Proc. R. Soc. Lond . B 237, 289-312 (1989 b )) by removal of the A current. A Ca 2+ -activated K + current, with Ca 2+ entering through T channels, is then added to give a model for a class of mammalian neurons in which the membrane potential oscillates in the subthreshold region following a hyperpolarizing current step. The properties of the model are represented using an experimentally observable bifurcation diagram. In the subthreshold region only three variables are required to explain the essential dynamic properties of the cell. In this three-dimensional space the solutions tend to lie on a surface which resembles a paraboloid. We use a simplified model of this model to explain both the dynamics of the solutions on this surface and the form of the bifurcation diagram.

Are the personality characteristics of astronauts related to their professional effectiveness? In order to answer this question, effectiveness and personality data were collected from 65 NASA astronauts. Several findings emerged from these data. Five personality subscales were related to effectiveness in one form or another. They were: high Negative Expressivity and Negative Communion (subordinate and gullible), low Impatience and Irritability, low Openness (to new ideas and experiences), low Negative Instrumentality (egoism) and high Agreeableness. Examining the graphs of these relationships indicated that they were not linear. This examination indicated that high levels on these undesirable personality characteristics (e.g., Impatience/Irritability) were distributed across all levels of effectiveness. Low levels of the undesirable personality characteristics were found only among the most effective astronauts. We concluded that these other-directed personality qualities will assume increasing importance in long-term spaceflight, and consequently, should be the focus of greater attention in future astronaut selection and training.

In this study, measures of astronaut effectiveness were administered to volunteers from the astronaut corps in order to validate psychological "select-in" criteria for long-duration space missions. Using a peer nomination format, astronauts rated their peers with whom they had either flown or trained. Factor analysis revealed two latent performance dimensions: job competence and group living. The job competence dimension measured the instrumental aspects relating to job knowledge and job performance. The group living dimension measured the interpersonal aspects relating to teamwork and desirability as a colleague on Space Station. Analyses revealed that the personality variables could explain a significant proportion of the variance in the group living performance dimension, but not the job competence performance dimension. The findings are not surprising since astronauts are highly screened on the basis of past attainment, but are not as highly screened on aspects relating to teamwork and interpersonal concerns.

Ultrahigh-molecular-weight polyethylene (UHMWPE) is used extensively in total joint replacements, particularly in hip and knee joints. At present, there is extensive concern with the long-term consequences of wear of this material, specifically osteolytic reactions to wear debris. The relationship of wear behavior to polymer morphology is almost completely unknown. Information on the effects of radiation sterilization on crystallinity is available, but gross conflicts exist. A central problem is the release, over long time periods, of huge numbers of submicron particles by wear. It has not been generally recognized that short-term, severe wear and long-term wear of UHMWPE in total joint replacements are very different in character and results. When the long-term wear regime is correctly defined, it is clear that knowledge of the influence of structure and properties on this specific phenomenon is almost completely absent.

This study examined the reliability and convergent validity of three methods of peer and supervisory ratings of the effectiveness of individual NASA astronauts and their relationships with flight assignments. These two techniques were found to be reliable and relatively convergent. Seniority and a peer-rated Performance and Competence factor proved to be most closely associated with flight assignments, while supervisor ratings and a peer-rated Group Living and Personality factor were found to be unrelated. Results have implications for the selection and training of astronauts.

The effects of a concurrent HIV-1 and Mycobacterium avium infection in vitro were assessed in human peripheral blood-derived macrophages (M phi). M phi were infected with HIV-1Ba-L strain for 14 days then infected with M. avium (HIV/M. avium) or treated with LPS (HIV/LPS). At various times after M. avium or LPS treatment, Mo phi cultures were harvested for quantitation of HIV and M. avium replication, as well as M phi cellular viability. In addition, mRNA and supernatants were collected for assessment of induction of the cytokines TNF-alpha, IL-1 beta and IL-6. M. avium multiplication was greater in HIV-infected M phi, whereas no difference in virus production, based on p24 and RT values, was observed between HIV-infected cells and HIV/M. avium or HIV/LPS M phi. M. avium infection of HIV-1-infected M phi also caused a decrease in viability of the M phi. HIV-1/M. avium-infected M phi had a 24 h delay in induction of TNF-alpha steady state mRNA when compared with HIV/LPS or M. avium only or LPS-only treated M phi. HIV infection also increased the amount and the length of induction of IL-1 beta and IL-6 steady state mRNA stimulated by either M. avium or LPS. In addition, prolonged and increased protein production of TNF-alpha, IL-6, and IL-1 beta was observed in HIV/M. avium-infected cells when compared with the other treatments. In direct contrast to M. avium infection, no significant differences in LPS-induced protein production of the three cytokines was observed between HIV-1-infected and -noninfected M phi. Treatment of HIV/M. avium-infected cells with human rGM-CSF did not increase either the time or quantity of induction of TNF-alpha mRNA or protein production in HIV/M. avium-infected M phi. The increase in M. avium numbers, dysregulation of cytokine production, and subsequent cell death seen in vitro in HIV/M. avium-infected human M phi may reflect part of the underlying cause of the highly disseminated M. avium disease pattern observed in AIDS patients.

One hundred six astronaut applicants who had passed initial screening were evaluated for Axis I and Axis II DSM-III-R diagnoses using a structured psychiatric interview. Nine of 106 candidates (8.5%) met diagnostic criteria for six Axis I (including V-code), or Axis II disorders. The use of the NASA structured interview was effective in identifying past and present psychopathology in a group of highly motivated and healthy astronaut applicants. This was the first time that a structured interview had been used in such a setting for this purpose. The methodology described is applicable to any situation where the presence or history of psychopathology requires evaluation for job selection (e.g. pilot selection).

This work introduces a model which attempts to explain the intercellular recordings made by Wilcox, Gutnick & Christoph (1988) of low threshold oscillations in neurons in the lateral habenula nucleus. Our purpose here is not to discuss all the physiological details but rather to concentrate on the structure of the dynamical system that we think is responsible for the main aspects of the behavior of these low threshold oscillations. We are looking for a simple, low dimensional system of differential equations that describe a dynamical system whose behavior is qualitatively similar to that of the neurons studied by Wilcox, Gutnick, & Christoph (1988).

Understanding the pathophysiology of Pneumocystis carinii infection has been limited by the availability of methods for precisely measuring the interaction of P. carinii with host cells. Here we describe a new method which allows for the rapid assessment of P. carinii binding to, and internalization by, adherent alveolar macrophages. The method is based on the detection of fluorescein-labelled P. carinii by an automated fluorescence measurement system.

Growth of P. carinii in culture has been difficult to document in the absence of reliable methods for distinguishing live from dead organisms. We studied three markers of cell function in P. carinii during the course of short-term cell culture, and correlated these with the number of P. carinii present in culture supernatants. The markers were glucan synthase activity, esterase activity and cell membrane integrity. The last two were assessed by double staining with fluorescein diacetate and propidium iodide followed by analysis of fluorescence using flow cytometry. The rise in P. carinii number after 5 to 7 days in culture was associated with increased glucan synthase activity. Flow cytometry analysis of day-6 P. carinii cultures confirmed that over 80% of the organisms catalyzed the conversion of fluorescein diacetate to fluorescein and excluded propidium iodide. The demonstration of three indices of metabolic activity in an expanding P. carinii population has confirmed the efficacy of a culture system as a means of sustaining the continued activity, albeit short-lived, of viable P. carinii.

Pneumocystis carinii cells labeled with fluorescein isothiocyanate were co-cultured with tissue culture cells. Measurements of attachment was determined by the tissue culture cell fluorescence after washing out the P. carinii organisms. The effects of the extracellular matrix proteins, laminin and fibronectin, on the binding of P. carinii onto the monolayer of cultured cells were investigated for better understanding of organism-cell interactions. The internalization of P. carinii by MRC5 cells was observed.

Active tuberculosis is now recognized as a frequent and serious complication of infection with the human immunodeficiency virus (HIV), the causative agent of AIDS. HIV mediated alteration in host defenses against mycobacteria contribute to the magnitude and severity of this problem. HIV can affect a variety of cellular mechanisms important in the restriction of mycobacterial growth. Qualitative and quantitative defects in T lymphocyte function result from direct HIV infection of cells expressing the CD4 epitope, and can severely limit the production of macrophage activating cytokines capable of inducing an anti-mycobacterial state in cells of monocyte lineage. In addition, macrophages themselves are susceptible to HIV infection, and have been shown to be defective with respect to a variety of host defense functions. Both T4 lymphopenia and HIV infected macrophages are present in the lower respiratory tract of HIV infected individuals, a circumstance which likely underlies the unique susceptibility of HIV infected to tuberculosis.

A forced expiratory flow ratio, derived from the average slope of the maximum expiratory flow-volume (MEFV) curve over a specified volume interval, was examined in healthy asymptomatic cigarette smokers and nonsmokers. This index was developed to have the properties that it would be (1) simple to calculate, (2) less effort dependent than indices that incorporate peak flow, and (3) free of influence from the configurational detail and noise frequently occurring at higher lung volumes on MEFV curves. Forced expired vital capacity maneuvers were performed by participants in a worksite health promotion program. Data from asymptomatic individuals with normal pulmonary function were analyzed for 49 cigarette smokers and 52 nonsmokers; 25 individuals had MEFV curves collected twice over a one-year interval. The ratio of flow derived from an average MEFV slope to instantaneous flow was calculated over the lower half of the vital capacity. Flow ratios were expressed as a percentage of the instantaneous flow at 75 percent of the expired vital capacity (FR75). This ratio was reproducible from year 1 to year 2 (r = 0.86, p less than 0.0001). Furthermore, the FR75 was well correlated with age among cigarette smokers and nonsmokers (r = 0.68 and 0.63 respectively). The slope of the least squares regression equation relating FR75 to age was significantly greater among smokers than nonsmokers (2.90 percent per year vs. 1.73 percent per year, p less than 0.025). While there was a significant interactive influence of age and total pack-years on the FR75 (F = 2.91, p = 0.02), this index did not differ systematically by gender. We conclude that the FR25 is a more sensitive index of altered lung function in cigarette smokers than are results of conventional pulmonary function.

Ultra high molecular weight polyethylene (UHMPWE) is now the material of choice for total joint replacement prostheses, in combination with a metal surface against which the polymer articulates. As this material has now been in use in this application for approximately three decades and other limiting factors (e.g. loosening of the prosthesis) have been improved upon, it is appropriate to attempt a long-term prognosis.

Electromyographic recordings from the buccal muscles of Lymnaea during feeding has shown that there are 4 component phases in the feeding cycle. Cinephotography of feeding cycles has confirmed that these correspond to protraction, 2 phases of retraction, and an inactive phase. The 4 phases of muscle activity can also be related to the cycle of neural activity described previously (Benjamin & Rose, 1979). Thus types 6, 4 group, and type 8 cells are motoneurones involved in protraction and the two retraction phases, while the type 5 cell fires in the inactive period. The combination of physiological and anatomical approaches has led to the suggestion that the single and double input cells described by Benjamin & Rose (1979) are involved with the control of buccal and oesophageal activity respectively.

SUMMARY Concentrations of cortisol and testosterone in the plasma of adult male rhesus monkeys living in social groups were determined during a 27-h period. Capture and venipuncture of experienced, conditioned animals did not lead to a fall in the concentration of testosterone in the plasma during the 90 min immediately after removal from the group. Both plasma cortisol and plasma testosterone concentrations showed a significant fall and rise in samples collected every 3 h during a 27-h period, even though there was considerable individual variation. During the autumn breeding season, animals showed higher concentrations of testosterone at both 10.00 and 22.00 h compared with those observed at the same times during the summer. Even though animals demonstrated significant diurnal changes, testosterone samples withdrawn at the same time of day (10.00 h) on consecutive days were significantly correlated with one another (r = 0·65, n = 27, P < 0·01), suggesting the usefulness of sampling once a day to study potential environmental influences on plasma testosterone concentrations.