Oculopalatal tremor: variations on a theme by Guillain and Mollaret.

BACKGROUND: Oculopalatal tremor (OPT) is a delayed complication of a brainstem lesion, characterized by involuntary contractions of the soft palate associated with a synchronized ocular pendular nystagmus. MRI reveals inferior olivary nucleus hypersignal/hypertrophy (IONH). Our objective was to refine the clinical profile of patients with OPT and to report a few oddities in both presentation and evolution. METHODS: We performed a retrospective study of patients diagnosed with OPT and a literature search. RESULTS: From our database, we retrieved 5 men and 3 women with a diagnosis of OPT. Eighty-two patients with OPT were retrieved from the literature and were compiled with our series. The average age was 54 years and there was a male predominance. Brainstem vascular lesion was the most common etiology (80%). Prominent vertical pendular nystagmus was found in 90%. Dissociated nystagmus was mostly associated to unilateral contralateral IONH on MRI, while bilateral symmetrical nystagmus was due to a bilateral IONH in the majority of cases. Three oddities were found amongst our 8 patients: prominent nystagmus ipsilateral to IONH; disappearance of IONH on MRI despite persisting nystagmus, and asymptomatic OPT. CONCLUSION: The clinical profile of OPT is rather stereotyped. Rarely do patients deviate from the classical description of OPT.

Predictive analysis and mapping of indoor radon concentrations in a complex environment using kernel estimation: an application to Switzerland.

PURPOSE: The aim of this study was to develop models based on kernel regression and probability estimation in order to predict and map IRC in Switzerland by taking into account all of the following: architectural factors, spatial relationships between the measurements, as well as geological information. METHODS: We looked at about 240,000 IRC measurements carried out in about 150,000 houses. As predictor variables we included: building type, foundation type, year of construction, detector type, geographical coordinates, altitude, temperature and lithology into the kernel estimation models. We developed predictive maps as well as a map of the local probability to exceed 300 Bq/m(3). Additionally, we developed a map of a confidence index in order to estimate the reliability of the probability map. RESULTS: Our models were able to explain 28% of the variations of IRC data. All variables added information to the model. The model estimation revealed a bandwidth for each variable, making it possible to characterize the influence of each variable on the IRC estimation. Furthermore, we assessed the mapping characteristics of kernel estimation overall as well as by municipality. Overall, our model reproduces spatial IRC patterns which were already obtained earlier. On the municipal level, we could show that our model accounts well for IRC trends within municipal boundaries. Finally, we found that different building characteristics result in different IRC maps. Maps corresponding to detached houses with concrete foundations indicate systematically smaller IRC than maps corresponding to farms with earth foundation. CONCLUSIONS: IRC mapping based on kernel estimation is a powerful tool to predict and analyze IRC on a large-scale as well as on a local level. This approach enables to develop tailor-made maps for different architectural elements and measurement conditions and to account at the same time for geological information and spatial relations between IRC measurements.

Optimum Enforcement Level for Traffic Weight Operations, HR-138, Appendices, 1968

Appendices for HR-138.

PixFRET, an ImageJ plug-in for FRET calculation that can accommodate variations in spectral bleed-throughs.

Fluorescence resonance energy transfer (FRET) allows the user to investigate interactions between fluorescent partners. One crucial issue when calculating sensitized emission FRET is the correction for spectral bleed-throughs (SBTs), which requires to calculate the ratios between the intensities in the FRET and in the donor or acceptor settings, when only the donor or acceptor are present. Theoretically, SBT ratios should be constant. However, experimentally, these ratios can vary as a function of fluorophore intensity, and assuming constant values may hinder precise FRET calculation. One possible cause for such a variation is the use of a microscope set-up with different photomultipliers for the donor and FRET channels, a set-up allowing higher speed acquisitions on very dynamic fluorescent molecules in living cells. Herein, we show that the bias introduced by the differential response of the two PMTs can be circumvented by a simple modeling of the SBT ratios as a function of fluorophore intensity. Another important issue when performing FRET is the localization of FRET within the cell or a population of cells. We hence developed a freely available ImageJ plug-in, called PixFRET, that allows a simple and rapid determination of SBT parameters and the display of normalized FRET images. The usefulness of this modeling and of the plug-in are exemplified by the study of FRET in a system where two interacting nuclear receptors labeled with ECFP and EYFP are coexpressed in living cells.