Image restoration in astronomy: a Bayesian perspective

When preparing an article on image restoration in astronomy, it is obvious that some topics have to be dropped to keep the work at reasonable length. We have decided to concentrate on image and noise models and on the algorithms to find the restoration. Topics like parameter estimation and stopping rules are also commented on. We start by describing the Bayesian paradigm and then proceed to study the noise and blur models used by the astronomical community. Then the prior models used to restore astronomical images are examined. We describe the algorithms used to find the restoration for the most common combinations of degradation and image models. Then we comment on important issues such as acceleration of algorithms, stopping rules, and parameter estimation. We also comment on the huge amount of information available to, and made available by, the astronomical community.

Visual activity predicts auditory recovery from deafness after adult cochlear implantation.

Modern cochlear implantation technologies allow deaf patients to understand auditory speech; however, the implants deliver only a coarse auditory input and patients must use long-term adaptive processes to achieve coherent percepts. In adults with post-lingual deafness, the high progress of speech recovery is observed during the first year after cochlear implantation, but there is a large range of variability in the level of cochlear implant outcomes and the temporal evolution of recovery. It has been proposed that when profoundly deaf subjects receive a cochlear implant, the visual cross-modal reorganization of the brain is deleterious for auditory speech recovery. We tested this hypothesis in post-lingually deaf adults by analysing whether brain activity shortly after implantation correlated with the level of auditory recovery 6 months later. Based on brain activity induced by a speech-processing task, we found strong positive correlations in areas outside the auditory cortex. The highest positive correlations were found in the occipital cortex involved in visual processing, as well as in the posterior-temporal cortex known for audio-visual integration. The other area, which positively correlated with auditory speech recovery, was localized in the left inferior frontal area known for speech processing. Our results demonstrate that the visual modality's functional level is related to the proficiency level of auditory recovery. Based on the positive correlation of visual activity with auditory speech recovery, we suggest that visual modality may facilitate the perception of the word's auditory counterpart in communicative situations. The link demonstrated between visual activity and auditory speech perception indicates that visuoauditory synergy is crucial for cross-modal plasticity and fostering speech-comprehension recovery in adult cochlear-implanted deaf patients.

Mothers' and fathers' views of the interdependence of their relationships with their infant: a systems perspective on early family relationships.

This study examined the interrelatedness of mother-infant and father-infant relationships as they develop over the first 4 months postpartum as well as the dynamics used by the couple to balance these relationships. First-time mother-father couples (n = 18) were interviewed separately at 1, 6, and 16 weeks postpartum using the Parent-Infant Relationship Interview. The data were analyzed using in-depth qualitative strategies. The parents' core themes of their early family relationships ranged from an undifferentiated unit at 1 week, to being a highly disorganized unit at 6 weeks, to a more integrated unit at 16 weeks. These results suggest that one should be thinking of early family relationships and parenting in terms of "messy processes" out of which new ways of being together are created. This disorganization plays a fundamental role in the establishment of early family relationships and warrants further empirical and clinical attention.

State of genomics and epigenomics research in the perspective of HIV cure.

PURPOSE OF REVIEW: One of the seven key scientific priorities identified in the road map on HIV cure research is to 'determine the host mechanisms that control HIV replication in the absence of therapy'. This review summarizes the recent work in genomics and in epigenetic control of viral replication that is relevant for this mission. RECENT FINDINGS: New technologies allow the joint analysis of host and viral transcripts. They identify the patterns of antisense transcription of the viral genome and its role in gene regulation. High-throughput studies facilitate the assessment of integration at the genome scale. Integration site, orientation and host genomic context modulate the transcription and should also be assessed at the level of single cells. The various models of latency in primary cells can be followed using dynamic study designs to acquire transcriptome and proteome data of the process of entry, maintenance and reactivation of latency. Dynamic studies can be applied to the study of transcription factors and chromatin modifications in latency and upon reactivation. SUMMARY: The convergence of primary cell models of latency, new high-throughput quantitative technologies applied to the study of time series and the identification of compounds that reactivate viral transcription bring unprecedented precision to the study of viral latency.

"Indemniser les planteurs pour abolir l'esclavage ? Entre économie, éthique et politique : une étude des débats parlementaires britanniques et français (1788-1848) dans une perspective comparée".

RESUME DE THESEUne majorité d'abolitions dans le Nouveau Monde (1777-1888) donne lieu à l'octroi d'indemnités aux propriétaires d'esclaves. Si cet aspect des émancipations n'a pas retenu l'attention des spécialistes jusqu'à présent, il s'agit d'un phénomène récurrent dans les Amériques. L'étude globale de la question de l'indemnité par l'examen des objectifs d'une telle mesure, de ses enjeux, ainsi que de son coût pour les Etats concernés, constitue ainsi l'ambition de cette recherche.L'originalité de la démarche adoptée réside dans le choix de la comparaison comme mode d'investigation et dans la sélection des débats parlementaires comme sources de travail. Une scène d'investigation sur deux niveaux a été construite. Les processus d'indemnisation britannique et français - jugés les plus représentatifs - ont été traités par le biais de sources, les autres cas par la littérature secondaire. Les discussions tenues de 1788 à 1848 aux Chambres des Communes et des députés ont été isolées comme bases d'investigation.Cette recherche démontre que la question de l'indemnité - bien que délaissée par les historiens qui ne l'ont pas perçue comme telle - constitue une cheville ouvrière d'une émancipation. Bien plus, l'étude du thème de l'indemnité - mesure s'inscrivant dans le concept d'économie morale - élargit l'angle de vue au-delà des seuls enjeux d'une abolition jusqu'à présent privilégiés. Outre des facteurs juridiques et économiques, des éléments sociaux et politiques doivent en effet être considérés, qui permettent de mieux cerner - par le biais de l'indemnité - la problématique complexe d'une abolition.

Auditory Neurons with Transitory Axons to Visual Areas Form Short Permanent Projections.

The kitten's auditory cortex (including the first and second auditory fields AI and AII) is known to send transient axons to either ipsi- or contralateral visual areas 17 and 18. By the end of the first postnatal month the transitory axons, but not their neurons of origin, are eliminated. Here we investigated where these neurons project after the elimination of the transitory axon. Eighteen kittens received early (postnatal day (pd) 2 - 5) injections of long lasting retrograde fluorescent traces in visual areas 17 and 18 and late (pd 35 - 64) injections of other retrograde fluorescent tracers in either hemisphere, mostly in areas known to receive projections from AI and AII in the adult cat. The middle ectosylvian gyrus was analysed for double-labelled neurons in the region corresponding approximately to AI and AII. Late injections in the contralateral (to the analysed AI, AII) hemisphere including all of the known auditory areas, as well as some visual and 'association' areas, did not relabel neurons which had had transient projections to either ipsi- or contralateral visual areas 17 - 18. Thus, AI and AII neurons after eliminating their transient juvenile projections to visual areas 17 and 18 do not project to the other hemisphere. In contrast, relabelling was obtained with late injections in several locations in the ipsilateral hemisphere; it was expressed as per cent of the population labelled by the early injections. Few neurons (0 - 2.5%) were relabelled by large injections in the caudal part of the posterior ectosylvian gyrus and the adjacent posterior suprasylvian sulcus (areas DP, P, VP). Multiple injections in the middle ectosylvian gyrus relabelled a considerably larger percentage of neurons (13%). Single small injections in the middle ectosylvian gyrus (areas AI, AII), the caudal part of the anterior ectosylvian gyrus and the rostral part of the posterior ectosylvian gyrus relabelled 3.1 - 7.0% of neurons. These neurons were generally near (<2.0 mm) the outer border of the late injection sites. Neurons with transient projections to ipsi- or contralateral visual areas 17 and 18 were relabelled in similar proportions by late injections at any given location. Thus, AI or AII neurons which send a transitory axon to ipsi- or contralateral visual areas 17 and 18 are most likely to form short permanent cortical connections. In that respect, they are similar to medial area 17 neurons that form transitory callosal axons and short permanent axons to ipsilateral visual areas 17 and 18.