Correctness of an STM Haskell implementation

A concurrent implementation of software transactional memory in Concurrent Haskell using a call-by-need functional language with processes and futures is given. The description of the small-step operational semantics is precise and explicit, and employs an early abort of conflicting transactions. A proof of correctness of the implementation is given for a contextual semantics with may- and should-convergence. This implies that our implementation is a correct evaluator for an abstract specification equipped with a big-step semantics

THE INFLUENCE OF DEPRESSIVE SYMPTOMS ON FATHERS’ BEHAVIORS AND ATTITUDES

The present study examines the impact of young, poor, unwed fathers on their family by investigating the influence of depressive symptom frequency on fathers’ relationship with their children and partners. Couples from seven American cities with populations over 200,000 were recruited and interviewed about such areas of life as romantic and parental relationships, health, and employment at the hospital within 24 hours after the birth of their child. An Item Response Theory (IRT) within-group analysis of the 1,759 African-, Caucasian-, Hispanic-, Asian-, and Native American fathers in the study yielded a 3-class clustering of depressive symptoms. Class 1 fathers had the lowest frequency of depressive symptom expression; class 2 fathers had a low frequency; and class 3 fathers had low to medium rates of depressive symptoms. Multivariate statistics revealed that depressive class membership predicted domestic violence toward fathers’ partners but not affection toward their children. The importance of the parental behavior of teaching children about life, however, varied by class, with class 2 fathers most highly endorsing this behavior. Implications of young, unwed, poor fathers' behaviors and attitudes toward their children and romantic partners will be discussed in terms of men's contributions to family life.

Toward a numerical deshaker for PFS

The Planetary Fourier Spectrometer (PFS) onboard Mars Express (MEx) is the instrument with the highest spectral resolution observing Mars from orbit since January 2004. It permits studying the atmospheric structure, major and minor compounds. The present time version of the calibration is limited by the effects of mechanical vibration, currently not corrected. We proposed here a new approach to correct for the vibrations based on semi-blind deconvolution of the measurements. This new approach shows that a correction can be done efficiently with 85% reduction of the artefacts, in a equivalent manner to the stacking of 10 spectra. Our strategy is not fully automatic due to the dependence on some regularisation parameters. It may be applied on the complete PFS dataset, correcting the large-scale perturbation due to microvibrations for each spectrum independently. This approach is validated on actual PFS data of Short Wavelength Channel (SWC), perturbed by microvibrations. A coherence check can be performed and also validate our approach. Unfortunately, the coherence check can be done only on the first 310 orbits of MEx only, until the laser line has been switch off. More generally, this work may apply to numerically "deshake" Fourier Transform Spectrometer (FTS), widely used in space experiments or in the laboratory.Comment: 18 pages, 8 figures, submitted to Planetary and Space Scienc