Interactive Shadow Removal and Ground Truth for Variable Scene Categories

We present an interactive, robust and high quality method for fast shadow removal. To perform detection we use an on-the-fly learning approach guided by two rough user inputs for the pixels of the shadow and the lit area. From this we derive a fusion image that magnifies shadow boundary intensity change due to illumination variation. After detection, we perform shadow removal by registering the penumbra to a normalised frame which allows us to efficiently estimate non-uniform shadow illumination changes, resulting in accurate and robust removal. We also present the first reliable, validated and multi-scene category ground truth for shadow removal algorithms which overcomes limitations in existing data sets -- such as inconsistencies between shadow and shadow-free images and limited variations of shadows. Using our data, we perform the most thorough comparison of state of the art shadow removal methods to date. Our algorithm outperforms the state of the art, and we supply our P-code and evaluation data and scripts to encourage future open comparisons

CONSTRUCTION AND PERCEPTUAL EVALUATION OF A 3D HEAD MODEL

Abstract This paper presents a method to construct a compact 3D head model capable of synthesizing realistic face expressions with subtle details such as wrinkles and muscle folds. The model is assessed by Psychologists using the certified FACS coding method. Such a compact and accurate model offers a large market potential not only in Computer Graphics industries but also in low-bandwidth applications e.g. tele-conferencing, and provides a valuable novel tool for Perceptual Studies. Method and Implementation The method used to construct the 3D head model in this work is inspired from the 2D Active Appearance Model described in Besides, a synthesized face looks more authentic if not only it appears like a human, but also moves like a human. Therefore, it is very important to accurately model the dynamics of the facial expressions. Not many researches have achieved this task so far in 3D animation, which is mostly due to the limitations of their data capture equipments. In this research, we use a fast 3D video camera (48fps) to capture our training data, which allows to model a fine temporal dynamic of the face movements. Finally, we combine the method described above with FACS coding to further improve the precision of our head model. FACS is a certified method used in Psychology to study facial movements Results Our training data consists of short video sequences of Action Units (about 60 frames each). After building a joint PCA model of shape and texture, we obtain a set of Eigenvectors which represent the different modes of variations of the facial changes. Conclusion We have successfully built a 3D head model capable of synthesizing realistic-looking face expressions, reproducing accurate skin folds and expression dynamics. We plan to use this model to study and model facial idiosyncrasies

The PI3K p110δ regulates expression of CD38 on regulatory T cells.

The PI3K pathway has emerged as a key regulator of regulatory T cell (Treg) development and homeostasis and is required for full Treg-mediated suppression. To identify new genes involved in PI3K-dependent suppression, we compared the transcriptome of WT and p110δ(D910A) Tregs. Among the genes that were differentially expressed was the gene for the transmembrane cyclic ADP ribose hydrolase CD38. Here we show that CD38 is expressed mainly by a subset of Foxp3(+)CD25(+)CD4(+) T cells originating in the thymus and on Tregs in the spleen. CD38(high) WT Tregs showed superior suppressive activity to CD38(low) Tregs, which failed to upregulate CD73, a surface protein which is important for suppression. However, Tregs from heterozygous CD38(+/-) mice were unimpaired despite lower levels of CD38 expression. Therefore, CD38 can be used as a marker for Tregs with high suppressive activity and the impaired Treg function in p110δ(D910A) mice can in part be explained by the failure of CD38(high) cells to develop

Comparative Genomics of the Anopheline Glutathione S-Transferase Epsilon Cluster

Enzymes of the glutathione S-transferase (GST) family play critical roles in detoxification of xenobiotics across many taxa. While GSTs are ubiquitous both in animals and plants, the GST epsilon class (GSTE) is insect-specific and has been associated with resistance to chemical insecticides. While both Aedes aegypti and Anopheles gambiae GSTE clusters consist of eight members, only four putative orthologs are identifiable between the species, suggesting independent expansions of the class in each lineage. We used a primer walking approach, sequencing almost the entire cluster from three Anopheles species (An. stephensi, An. funestus (both Cellia subgenus) and An. plumbeus (Anopheles subgenus)) and compared the sequences to putative orthologs in An. gambiae (Cellia) in an attempt to trace the evolution of the cluster within the subfamily Anophelinae. Furthermore, we measured transcript levels from the identified GSTE loci by real time reverse transcription PCR to determine if all genes were similarly transcribed at different life stages. Among the species investigated, gene order and orientation were similar with three exceptions: (i) GSTE1 was absent in An. plumbeus; (ii) GSTE2 is duplicated in An. plumbeus and (iii) an additional transcriptionally active pseudogene (ψAsGSTE2) was found in An. stephensi. Further statistical analysis and protein modelling gave evidence for positive selection on codons of the catalytic site in GSTE5 albeit its origin seems to predate the introduction of chemical insecticides. Gene expression profiles revealed differences in expression pattern among genes at different life stages. With the exception of GSTE1, ψAsGSTE2 and GSTE2b, all Anopheles species studied share orthologs and hence we assume that GSTE expansion generally predates radiation into subgenera, though the presence of GSTE1 may also suggest a recent duplication event in the Old World Cellia subgenus, instead of a secondary loss. The modifications of the catalytic site within GSTE5 may represent adaptations to new habitats