A controlled, prospective, 1-year trial of citalopram in the treatment of panic disorder

BACKGROUND: The objective of this study was to evaluate the efficacy and tolerability of citalopram in the long-term treatment of adult outpatients with panic disorder with or without agoraphobia. METHOD: Patients in this double-blind, parallel-group trial were assigned to 1 of 3 fixed dosage ranges of citalopram (10 or 15 mg/day, 20 or 30 mg/day, or 40 or 60 mg/day), 1 dosage range of clomipramine (60 or 90 mg/day), or placebo. After the completed 8-week acute treatment period, the eligible patients could continue the treatment for up to 1 year. Of the 475 patients who were randomly assigned for the short-term trial, 279 agreed to continue double-blind treatment at their assigned doses. The primary efficacy measure used was the Clinical Anxiety Scale panic attack item, and the response was defined as no panic attacks (score of 0 or 1). The other key measures used were the Physician's Global Improvement Scale, the Patient's Global Improvement Scale, and the Hamilton Rating Scale for Anxiety (HAM-A). RESULTS: In all drug-treated groups, except the group receiving the lowest citalopram dose, the treatment outcome was generally better than with placebo. As determined by a life table analysis of response, the probability of response during the 12 months was significantly greater with all treatment regimens than with placebo (p < .05), with citalopram 20 or 30 mg/day demonstrating the best response. Panic attacks tended to disappear in all patients remaining in the study until the end of follow-up. Analysis of the difference in the number of patients in different treatment groups remaining in the study (perhaps the best measure of long-term efficacy) also demonstrated that the patients treated with citalopram in dosage ranges of 20 or 30 mg/day and 40 or 60 mg/day had better response than placebo-treated patients (p < .0002 and p < .004, respectively). HAM-A and Global Improvement Scale scores also showed that patients treated with active drug showed greater improvement than placebo-treated patients. All treatment groups showed no new or exceptional adverse event clusters. CONCLUSION: Citalopram in the dosage range of 20 to 60 mg/day is effective, well tolerated, and safe in the long-term treatment of patients who have panic disorder.     

Feasibility of airborne imaging spectrometry for lake monitoring—a case study of spatial chlorophyll a distribution in two meso-eutrophic lakes

The spatial distribution of the sum of chlorophyll a and phaeophytin a concentrations (chl-a) under light wind (0–2 m s^?1) conditions was studied in two lakes with an AISA airborne imaging spectrometer. Chl-a was interpreted from AISA radiance data using an algorithm based on the near-infrared (700–710 nm) to red (660–665 nm) ratio. The results of Lake Lohjanjärvi demonstrate that the use of one monitoring station can result in over- or underestimation by 29–34% of the overall chl-a compared with an AISA-based estimation. In Lake Hiidenvesi, the AISA-based estimation for the mean chl-a with 95% confidence limits was 25.19±2.18 µg l^?1. The use of AISA data together with chl-a measured at 15 in situ sampling stations decreased the relative standard error of the mean chl-a estimation from 20.2% to 4.0% compared with the use of 15 discrete samples only. The relative standard error of the mean chl-a using concentrations at the three routine monitoring stations was 15.9 µg l^?1 (63.1%). The minimum and maximum chl-a in Lake Hiidenvesi were 2 and 101 µg l^?1, 6 and 70 µg l^?1 and 11 and 66 µmg l^?1, estimated using AISA data, data from 15 in situ stations and data from three routine in situ stations, respectively.     

Indoor dispersion of airborne nano and fine particles: Main factors affecting spatial and temporal distribution in the frame of exposure modeling

A particle exposure experiment inside a large climate‐controlled chamber was conducted. Data on spatial and temporal distribution of nanoscale and fine aerosols in the range of mobility diameters 8‐600 nm were collected with high resolution, for sodium chloride, fluorescein sodium, and silica particles. Exposure scenarios studied included constant and intermittent source emissions, different aggregation conditions, high (10 h^?1) and low (3.5 h^?1) air exchange rates (AERs) corresponding to chamber Reynolds number, respectively, equal to 1 × 10⁵ and 3 × 10⁴. Results are presented and analyzed to highlight the main determinants of exposure and to determine whether the assumptions underlying two‐box models hold under various scenarios. The main determinants of exposure found were the source generation rate and the ventilation rate. The effect of particles nature was indiscernible, and the decrease of airborne total number concentrations attributable to surface deposition was estimated lower than 2% when the source was active. A near‐field/far‐field structure of aerosol concentration was always observed for the AER = 10 h^?1 but for AER = 3.5 h^?1, a single‐field structure was found. The particle size distribution was always homogeneous in space but a general shift of particle diameter (?8% to +16%) was observed between scenarios in correlation with the AER and with the source position, presumably largely attributable to aggregation.     

On the aperiodic and odd correlations of the binaryShanbhag-Kumar-Helleseth sequences

A previously derived upper bound on hybrid sums over Galois rings is combined with a method due to Vinogradov (1954) to obtain an upper bound for the maximum aperiodic and odd correlations of the binary sequences constructed by Shanbhag, Kumar, and Helleseth (see Proc. 1995 IEEE Int. Symp. on Information Theory, 1995)     

Inversion behavior in core- and cladding-pumped Yb-doped fiber photodarkening measurements

Yb-doped fibers are widely used in applications requiring high average output powers and high power pulse amplification. Photodarkening of the Yb-doped silicate glass core potentially limits the lifetime or efficiency of such fiber devices. In many studies of photodarkening, two principal methods of controllably inducing an inversion are used, namely, cladding pumping and core pumping of the sample. We present simulation results describing the key differences in the inversion profiles of samples of different physical parameters in these two cases, and we discuss the problems and possibilities that arise in benchmarking fibers of various physical parameters. Based on the simulation and experimental work, we propose guidelines for photodarkening benchmarking measurements and show examples of measurements made within and outside of the guidelines.     

Photodarkening rate in Yb-doped silica fibers

Yb-doped fibers are widely used in laser applications requiring high average output powers and high-peak-power pulse amplification. Photodarkening (PD) is recognized as one limiting factor in these fibers when pumped with high-intensity radiation. We describe an approach for performing quantitative PD studies of fibers, and we present measurements of the rate of PD in Yb-doped single-mode fibers with varying inversion levels. The method is applicable to large-mode-area fibers. We observed a seventh-order dependence of the PD rate on the excited-state Yb concentration for two different fibers; this result implies that PD of a Yb-doped fiber source fabricated using a particular fiber will be strongly dependent on the configuration of the device.