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Discrete arc structures were identified from EISCAT data on March 11, 1984 which were simultaneously recorded on All-Sky camera pictures from the Kilpisjarvi station in Finland. From the electric field measurements supplied by the tri-static UHF facility, some privileged orientation has been found through the requirement of a uniform tangential electric field across the arc structure, which corresponds to the preferential arc alignment as deduced from camera pictures. Additional fold structures, resolved by the All-Sky camera, develop along the preexisting arcs which still organize the electric field fluctuations in their vicinity.

The MICADO instrument has been built to measure temperature and wind in the E - and F -regions. It employs a thermally stable field-compensated Michelson interferometer to allow wind measurements. During the winter of 1988–1989, the MICADO instrument was operated at Sodankyla (67°22′N, Finland). Measurements were made by observing the O 1 S (low thermosphere) and the O 1 D lines (high thermosphere) emission. Two co-ordinated campaigns were organized with the EISCAT radar, which operated in special modes. Neutral wind and temperature are derived from EISCAT data. Results of the two instruments are shown. The differences between the two sets of results are discussed and show that most of the discrepancy is due to the presence of vertical winds during the observations where the magnetic activity was high.

Objective Recent research by Wetherell et al. investigating the differential response to group-administered cognitive behavior therapy (CBT) for generalized anxiety disorder (GAD) in older adults found that GAD severity, homework adherence, and psychiatric comorbidity predicted statistically significant improvement. The current study investigated whether the presence/absence of cognitive errors on separate domains of the Mini-Mental State Exam (MMSE) predicted baseline differences in symptom severity and improvement following CBT, above and beyond already established predictors. Methods Baseline characteristics were investigated in a sample of 208 older patients diagnosed with GAD. Predictors of treatment response were examined in a subsample of 65 patients who completed CBT and were included in a prior study by Wetherell et al. of response predictors. Results Results from the baseline sample indicated that only subjects who committed an error on the MMSE Working Memory domain exhibited increased severity in anxiety and depressive symptoms. Results from the treatment sample indicated that an error on the MMSE Orientation domain was a significant predictor of outcome at 6-month follow-up, while controlling for previously established predictors. Patients who committed at least one error in this domain showed decreased response relative to patients who committed no errors. Conclusion In this sample of older adults diagnosed with GAD, poor performance on the MMSE Working Memory domain was associated with increased baseline anxiety and depression, while baseline performance differences on the MMSE Orientation domain predicted outcome six months after CBT intervention.

Telephone assessments are commonly used in mental health research and may be especially beneficial in older populations. The current study assessed the psychometric properties of the Penn State Worry Questionnaire (T. J. Meyer, M. L. Miller, R. L. Metzger, & T. D. Borkovec, 1990) and the Beck Depression Inventory--II (A. T. Beck, R. A. Steer, & G. K. Brown, 1996), when administered over the telephone in an older adult population. Results indicate no differences in mean symptom level or internal consistency across two modes of administration. Correlations between the in-person and telephone-administered measures and diagnostic categories suggest adequate validity of the telephone-administered measures. With this demonstrated evidence, the telephone assessment method can be applied in a variety of research and clinical settings.

Dayside poleward moving auroral forms (PMAFs) were detected between 06:30 and 07:00 UT on December 16, 1998, by the meridian scanning photometer and the all-sky camera at Ny Ålesund, Svalbard. Simultaneous SuperDARN HF radar measurements permitted the study of the associated ionospheric velocity pattern. A good general agreement is observed between the location and movement of velocity enhancements (flow channels) and the PMAFs. Clear signatures of equatorward flow were detected in the vicinity of PMAFs. This flow is believed to be the signature of a return flow outside the reconnected flux tube, as predicted by the Southwood model. The simulated signatures of this model reproduce globally the measured signatures, and differences with the experimental data can be explained by the simplifications of the model. Proposed schemes of the flow modification due to the presence of several flow channels and the modification of cusp and region 1 field-aligned currents at the time of sporadic reconnection events are shown to fit well with the observations.Key words: Ionosphere (auroral ionosphere; plasma convection) - Magnetospheric physics (magnetopause; cusp and boundary layers)

International audience; The combination of radial velocities measured by a pair of Super Dual Auroral Radar Network (SuperDARN) HF coherent radars gives, in their common field of view, the velocity vectors in a plane perpendicular to the magnetic field. The standard merging is based on a natural grid defined by the beam intersections, which provides a resolution varying between 90 and 180 km (depending upon the distance to the radars). This allows the description of structures with a typical scale size (L) of the order of 500 km. The present study is devoted to a merging method which takes advantage of individual radar grids to enhance the resolution (L • 200 km). After a brief description of the standard merging method, we define the high-resolution grid and discuss the potential problems which have to be overcome. The first problem concerns the localization of the scattering volume, whereas the second one deals with the independence of the velocity vectors. These two limitations have been addressed in previous studies [Andrd et al., 1997; Barthes et al., 1998]. In the method proposed here, several velocity vectors are determined at each grid point, from which the selection is made by using the hypothesis of minimization of the divergence magnitude. The selected map is the one which minimizes the divergence. The performances are tested and compared to the standard merging algorithm through simulated double vortices. Finally, we apply this method to real data, and show, through two examples, its ability to describe small-scale structures (L m 200 kin).

An analysis of several global measures of high-latitude ionospheric electrodynamic activity is undertaken on the basis of results obtained from the Assimilative Mapping of Ionospheric Electrodynamics (AMIE) procedure applied to incoherent scatter radar and ground magnetometer observations for January 18–19, 1984. Different global measures of electric potentials, currents, resistances, and energy transfer from the magnetosphere show temporal variations that are generally well correlated. We present parameterizations of these quantities in terms of the AE index and the hemispheric power index of precipitating auroral particles. It is shown how error estimates of the mapped electric fields can be used to correct the estimation of Joule heating. Global measures of potential drop, field-aligned current, and Joule heating as obtained by the AMIE procedure are compared with similar measures presented in previous studies. Agreement is found to within the uncertainties inherent in each study. The mean potential drop through which field-aligned currents flow in closing through the ionosphere is approximately 28% of the total polar cap potential drop under all conditions during these 2 days. We note that order-of-magnitude differences can appear when comparing different global measures of total electric current flow and of effective resistances of the global circuit, so that care must be exercised in choosing characteristic values of these parameters for circuit-analogy studies of ionosphere-magnetosphere electrodynamic coupling.

Between May 1981 and June 1982 an intensive campaign of 33 coordinated observations was carried out using the three incoherent-scatter radars capable of probing the auroral zone. During this period the groups operating the Dynamic Explorer satellites and the STARE radar made special efforts to acquire data coincident with the radar observations. The objective of these MITHRAS experiments and subsequent analysis is to further our understanding of the interactions of the magnetosphere, the ionosphere, and the thermosphere, with special emphasis on local time/universal time variations. Three experimental modes with different time resolution and spatial coverage were used to examine different aspects of these interactions. The analysis of the extensive data set involves collaboration among groups of experimenters as well as between experimenters and theoreticians.

An open, randomized study to compare the effectiveness of triple-dose cefoxitin with the effectiveness of cephradine-tinidazole and with the result of nontreatment in patients undergoing abdominal hysterectomy was conducted from July 1983 to July 1984. One hundred ninety-nine patients were enrolled: 66 untreated control patients, 69 patients in the cephradine-tinidazole-treated group, and 64 patients in the cefoxitin-treated group. No significant differences were present in relation to age, pathologic condition, length of operation, blood loss, or length of hospital stay. That patients in both treatment groups had a lower incidence of postoperative febrile morbidity was not statistically significant.

The Finnish radar of CUTLASS has been operational since February 1995. Between 0620 and 0800 UT on August 25 1995, a region of ionospheric scatter, which was limited to only a few degrees of magnetic latitude, moved poleward at a rate of some 7 degrees per hour. The line of sight velocity measurements on a special high time resolution beam indicate a flow reversal boundary which moved poleward throughout the interval. Flow was towards (away from) the radar on the poleward (equatorward) side of the boundary. The flow towards the radar along this beam was at a high speed, >800 m s−1, while the speed away from the radar was less than 200 m s−1. Spatial plots indicate high speed flow away from the radar in the west of the field of view. A tentative interpretation is that the high speed flow is caused by lobe cell reconnection while the low speed flow is associated with either the contraction of the polar cap or due to viscous processes at the magnetopause.

The large-scale electric potential patterns, describing ionospheric convection, are estimated for northern high latitudes during January 18-19, 1984, from combined incoherent-scatter radar and ground magnetometer observations, using the technique of Richmond and Kamide (this issue). The patterns usually have a dominant two-cell characteristic, although the intensities, orientations and shapes of the cells undergo considerable changes with time. Often evident during substorm expansive phases is a “tongue” of low electric potential extending toward the east along the low-latitude edge of the high potential cell at night. Time-series plots of the maximum and minimum electric potentials show that they can respond rapidly to changes in the interplanetary magnetic field Bz component. Total estimated potential drops for this 2-day period range from about 15 kV up to 108 kV. The influence of the different types of data on the resultant estimated electric potential patterns is analyzed. Where available, the direct electric field observations by the radars primarily control the characteristics of the estimated potential patterns, while the magnetometer data have their greatest influence in regions where direct electric field measurements are unavailable. We also employ the statistical electric potential model of Foster et al. (1986) to help fill in the patterns in datasparse regions. For the present study, data coverage is often good enough that the statistical model plays only a secondary role in determining the estimated convection patterns. The ionospheric electrical conductance observations from the Sondrestrom and EISCAT radars are very important in helping modify the statistical conductance model of Fuller-Rowell and Evans (1987) to yield modified conductance distributions suitable for interrelating the electric fields, currents, and magnetic perturbations. Analysis of the statistical uncertainty in the estimated large-scale electric field patterns shows the uncertainty to exceed 50% in the polar cap and sub auroral regions and to be less than 20% only in the vicinity of the radar electric field observations.