Full aperture backscatter diagnostics for characterization of laser plasma instabilities at the extreme light infrastructure (ELI) beamlines

We report on the commissioning of a full aperture backscatter diagnostics station for the kilojoule, nanosecond high repetition rate L4n laser operating at a wavelength of 527 nm at the Extreme Light Infrastructure (ELI) - Beamlines, Dolni Brezany, Czech Republic. Light scattered back from laser-plasma interaction into the cone of the final focusing lens is captured and split into different channels to measure the signatures of laser plasma instabilities from stimulated Brillouin scattering, stimulated Raman scattering, and two plasmon decay with respect to back scattered energy, its spectrum, and its temporal profile. The performance was confirmed in a commissioning experiment with more than 800 shots at laser intensities ranging from 0.5 × 1013 to 1.1 × 1015 W cm-2. These diagnostics are permanently installed at ELI Beamlines, and can be used to understand the details of laser-plasma interactions in experiments with kJ and 527 nm light. The large number of shots that can be collected in an experimental campaign will allow us to study the details of the laser-plasma interaction with a high level of confidence.

A Multi-Anvil High Pressure System with Synchrotron X-Ray Probe: New Opportunities for In-Situ Materials Research at Simultaneously High Pressure and Temperature

We describe the multi-anvil, large-volume, high-pressure facility that is being constructed at the GeoSoilEnviroCARS (Sector 13) at the Advanced Photon Source, Argonne National Laboratory. Various multi-anvil, high-pressure apparatus will be used to cover pressure and temperature conditions up to 40 GPa and 3000 °C, respectively, with milimeter to centimeter sized samples. This national facility is open to all users, providing excellent opportunities for high pressure, high temperature experiments.

Impaired circadian waking arousal in narcolepsy-cataplexy

The 24-hour sleep/wake distributions of untreated patients with narcolepsy-cataplexy and matched normal habitual nappers were compared using home ambulatory monitoring. Subjects followed their usual sleep patterns including, for the habitual nappers, a self-selected daytime nap. There were no differences in 24-hour totals of sleep between groups other than a small increase in SWS in narcolepsy. Narcolepsy showed greater amounts of day sleep (stages 2, SWS, REM and total sleep) and less night sleep (stage 2, total sleep). Data were collapsed into 5 min epochs and entered into a matrix. The data in the two groups were then "wrapped" (re-aligned) around the 24 hours with phase 0 as each of the times of: evening sleep onset, onset of SWS, mid-point of night sleep and moment of morning awakening. In habitual nappers alignment beginning at morning wake-up produced the highest amplitude, least temporal dispersion and greatest kurtosis of daytime sleep (naps). The 24-hour sleep/wake distribution curves of both subject groups (data aligned at morning wake-up) based on collapsed data into 5 min bins then underwent curve fitting using 15th order polynomial regression. As with visual analyses of the raw data, the curve fits confirmed that the peak in daytime sleep propensity in narcoleptics was earlier by about 40 (2.66 hours). It was concluded that decreased daytime amplitude of a circadian arousal system was the most parsimonious explanation for the increased amount, broader temporal distribution and relative phase advance of day sleep in narcolepsy and that, as well, such a mechanism could explain a number of other features of the disease.

Factors associated with intended staff turnover and job search behaviour in services for people with intellectual disability

Staff turnover is a major problem in services for people with intellectual disability (ID). Therefore, understanding the reasons for staff turnover is vital for organizations seeking to improve their performance. The present study investigates the factors directly and indirectly associated with an intention to leave an organization and actual job search behaviour amongst staff in services for people with ID. As part of a large-scale survey of staff in services for people with ID, information was collected from 450 staff concerning intended turnover, job search behaviour and a wide range of factors potentially associated with these outcomes. Path analyses revealed that work satisfaction, job strain, younger staff age and easier subjective labour conditions were directly associated with intended turnover. The same factors, with the exception of younger staff age, were also directly associated with job search behaviour. Factors indirectly associated with these outcomes included wishful thinking, alienative commitment to the organization, lack of staff support, role ambiguity, working longer contracted hours, having a low-status job, a lack of influence over decisions at work and less orientation to working in community settings with people with ID. The models of staff turnover empirically derived in the present study confirm and extend previous research in this area. The implications for organizations are discussed.

Factors associated with staff stress and work satisfaction in services for people with intellectual disability

Staff stress and morale have been identified as major issues affecting the quality of services for people with intellectual disability. The present study investigates factors directly and indirectly associated with staff general distress, job strain and work satisfaction amongst staff in services for people with intellectual disability. As part of a large-scale survey of staff in services for people with intellectual disability, information was collected from 450 staff concerning general distress, job strain and work satisfaction, and a wide range of factors potentially associated with these outcomes. Path analyses revealed that three factors accounted for 28% of the variance in general distress scores: (I) wishful thinking, (2) stress linked to work-home conflict and (3) role ambiguity. Six factors accounted for 50% of the variance in job strain scores: (I) wishful thinking, (2) stress linked to a lack of staff support, (3) alienative commitment, (4) role ambiguity, (5) stressors linked to a low status job and (6) working longer contracted hours. Six factors accounted for 66% of the variance in work satisfaction scores: (I) stress linked to a low status job, (2) support from supervisors, (3) influence over work decisions, (4) alienative commitment, (5) support from colleagues and (6) older staff age. A range of factors indirectly associated with the three outcome measures was also identified. The models of general distress, job strain and work satisfaction empirically derived in the present study confirm and extend previous research in this area. The implications for organizations and future research are discussed.

Staff stressors and staff outcomes in services for adults with intellectual disabilities: the Staff Stressor Questionnaire

This paper reports on the development, psychometric properties, and validity of a self-report measure designed to assess potential stressors among staff in services for people with intellectual disabilities, the 33-item Staff Stressor Questionnaire (SSQ). A questionnaire including the SSQ and scales measuring staff outcomes was administered to 512 staff across seven services for people with intellectual disabilities. The SSQ was factor analyzed to produce seven subscales reflecting different potential stressors for staff: user challenging behavior; poor user skills; lack of staff support; lack of resources; low-status job; bureaucracy; and work-home conflict. The SSQ subscales showed adequate internal reliability in terms of Cronbach's alpha and mean inter-item correlations. Associations between SSQ subscale scores and different staff groups, and patterns of associations between SSQ subscales and a range of staff outcomes, provided evidence suggestive of the face-, construct-, and criterion-related validity of the questionnaire. The SSQ shows promise as a measure for assessing potential stressors for staff in services for people with intellectual disabilities. Further studies to examine the reliability, validity, and utility of the SSQ are recommended.

Organizational culture and staff outcomes in services for people with intellectual disabilities

Organizational culture has been shown by organizational psychology to influence important aspects of staff behaviour. In particular, mismatches between staff perceptions of real and ideal organizational cultures have been shown to be associated with a range of negative outcomes for staff, such as stress, sickness and staff turnover. The present study investigates organizational culture in services for people with intellectual disabilities. The aim was to discover the prevalent organizational cultures in these services, and associations between organizational culture and staff outcomes. As part of a large-scale survey of staff in services for people with intellectual disabilities, information concerning organizational culture and staff outcomes was collected from 450 staff. A self-report measure of real and ideal organizational culture produced nine dimensions of organizational culture: (I) tolerant/staff-oriented; (2) achievement-oriented; (3) innovative; (4) analytical; (5) social relationships; (6) rewarding staff; (7) stable work environment; (8) demanding; and (9) conflict management. These nine dimensions of organizational culture showed generally adequate psychometric properties. While there was some variation in organizational culture across services, there is little variation across staff with different job titles. Overall, the staff rated real organizational cultures to be relatively high in achievement orientation and fostering social relationships, and relatively low in managing conflict and providing rewards for staff. Staff rated ideal organizational cultures to be high in rewarding staff, being tolerant/staff-oriented and fostering social relationships, and low in demands on staff. Except for the dimension of making demands on staff, where staff rated organizations as considerably higher than ideal, staff generally rated organizations as being less than ideal on all dimensions of organizational culture. Organizational psychology theory predicts that poor 'person-organization fit' (i.e. a greater mismatch between real and ideal organizational culture) will be associated with a range of negative staff outcomes. This theory was largely supported by findings of the present study. The implications for practice and for future research are discussed.

Comparison of Fastpak with full-threshold 24-2 glaucoma field tests

BACKGROUND AND OBJECTIVES

The authors noted an underestimation of the mean deviation for field testing using the Fastpak (Humphrey Instruments, San Leandro, CA) strategy, and set out to define the extent of this difference.

PATIENTS AND METHODS

Sixty-seven eyes of 35 glaucomatous patients were examined. Patients received full-threshold 24-2 tests before and after the Fastpak strategy was used, each test on a different day. For some patients, another full-threshold test was performed using a different birth date in order to obtain a result uninfluenced by prior data.

RESULTS

The mean deviation (MD) was significantly underestimated by Fastpak compared with the full-threshold tests. The time taken for Fastpak was almost identical to that taken for full-threshold tests. Short-term fluctuation (SF) appeared to have very little reliability statistically, and, consistent with this, there was a greater concordance among pattern standard deviation (PSD) data than among corrected pattern standard deviation (CPSD) data.

CONCLUSION

Fastpak was an effective method for charting the visual field, but did so with greater variation than full-threshold tests. It significantly underestimated the MD, and this was not a fatigue effect. Fastpak was no faster than full-threshold testing in advanced glaucoma. CPSD was a less consistent reading than PSD in these glaucomatous patients.

Night sleep does not predict day sleep in narcolepsy

It has been suggested that the increased day sleep in narcolepsy-cataplexy is secondary to the known fragmentation and reduction of night sleep, there being no differences in 24 h sleep totals from normals. Twenty-two untreated patients underwent 24 h sleep wake recordings by ambulatory monitoring. Correlations were assessed by stepwise multiple regression between day sleep and night sleep measures. Almost no significant or near significant correlations emerged. It is concluded that day sleep in narcolepsy is based upon a different mechanism, perhaps a diurnal "subvigilance syndrome" of impaired arousal mechanisms.

Long-range, noncoherent laser Doppler velocimeter

An experimental demonstration of a long-range, noncoherent laser Doppler velocimeter (LDV) is presented. The LDV detects incoming Doppler-shifted signal photons by using the sharp spectral absorption features in atomic or molecular vapors. The edge of the absorption feature is used to convert changes in frequency to large changes in transmission. Preliminary measurements of wind velocity using seeded aerosols showed that the LDV results agreed with mechanical anemometer measurements to within the accuracy of the LDV measurements. With optimization the LDV will provide accurate range-resolved and vibration-tolerant wind-speed measurements at large distances.

Fast atomic line filter/field ionization detector

An experimental demonstration of a fast atomic line filter/field ionization detector (FALF/FID) is presented. The FALF/FID detects incoming signal photons by resonant absorption in an atomic vapor cell containing a strong electric field. Excited atoms are electric-field ionized after further excitation to a Stark-shifted Rydberg level by a pump laser tuned to a resonance in the ionization spectrum, providing an observed enhancement in the ionization rate of ten times over the continuum ionization threshold. Preliminary measurements of time response (<10 nsec) and quantum efficiency (>25%) indicate that with optimization the FALF/FID will provide high quantum efficiency, fast time response, and narrow-linewidth detection.

Ambulatory 24 hour sleep-wake monitoring in narcolepsy-cataplexy compared to matched controls

Twenty-four hour ambulatory sleep-wake recordings were made in 10 untreated patients with narcolepsy-cataplexy and 10 matched controls. Nocturnal sleep of narcoleptics was similar to descriptions of laboratory based recordings and was characterized by frequent sleep onset REM periods, high variability of REM latency, increased amounts of wakefulness after sleep onset, and low sleep efficiencies. Daytime portions in narcoleptics showed greater drowsiness and sleep than in controls with significantly higher amounts of stages 1A, 1B, 3, 4 and REM, more sleep episodes longer than 1 and longer than 10 min in duration, and high intersubject variability. On average, only 1.2 daytime sleep episodes began with sleep onset REM periods. There was a strong tendency in both groups towards a long mid-afternoon sleep episode often containing slow wave sleep (SWS) and which was significantly longer in narcoleptics. The mean interval between the onset of nocturnal SWS and the main daytime SWS peak was 14.1 h for narcoleptics and 13.6 h for controls. Daytime waking portions in narcoleptics showed significantly less 'active wakefulness' than in controls. There was no correlation between MSLT measures of sleepiness and amount of daytime sleep in ambulant recordings.