0000000001230390
AUTHOR
Luis Torres
A simple and efficient face detection algorithm for video database applications
The objective of this work is to provide a simple and yet efficient tool to detect human faces in video sequences. This information can be very useful for many applications such as video indexing and video browsing. In particular the paper focuses on the significant improvements made to our face detection algorithm presented by Albiol, Bouman and Delp (see IEEE Int. Conference on Image Processing, Kobe, Japan, 1999). Specifically, a novel approach to retrieve skin-like homogeneous regions is presented, which is later used to retrieve face images. Good results have been obtained for a large variety of video sequences. Peer Reviewed
Liver-specific methionine adenosyltransferase MAT1A gene expression is associated with a specific pattern of promoter methylation and histone acetylation: implications for MAT1A silencing during transformation.
Methionine adenosyltransferase (MAT) is the enzyme that catalyzes the synthesis of S-adenosylmethionine (AdoMet), the main donor of methyl groups in the cell. In mammals MAT is the product of two genes, MAT1A and MAT2A. MAT1A is expressed only in the mature liver whereas fetal hepatocytes, extrahepatic tissues and liver cancer cells express MAT2A. The mechanisms behind the tissue and differentiation state specific MAT1A expression are not known. In the present work we examined MAT1A promoter methylation status by means of methylation sensitive restriction enzyme analysis. Our data indicate that MAT1A promoter is hypomethylated in liver and hypermethylated in kidney and fetal rat hepatocytes…
DNA methylation and histone acetylation of rat methionine adenosyltransferase 1A and 2A genes is tissue-specific.
Methionine adenosyltransferase (MAT) catalyzes the biosynthesis of S-adenosylmethionine (AdoMet). In mammals MAT activity derives from two separate genes which display a tissue-specific pattern of expression. While MAT1A is expressed only in the adult liver, MAT2A is expressed in non-hepatic tissues. The mechanisms behind the selective expression of these two genes are not fully understood. In the present report we have evaluated MAT1A and MAT2A methylation in liver and in other tissues, such as kidney, by methylation-sensitive restriction enzyme digestion of genomic DNA. Our data indicate that MAT1A is hypomethylated in liver and hypermethylated in non-expressing tissues. The opposite situ…
Video preprocessing for audiovisual indexing
We address the problem of detecting shots of subjects that are interviewed in news sequences. This is useful since usually these kinds of scenes contain important and reusable information that can be used for other news programs. In a previous paper, we presented a technique based on a priori knowledge of the editing techniques used in news sequences which allowed a fast search of news stories (see Albiol, A. et al., 3rd Int. Conf. on Audio and Video-based Biometric Person Authentication, p.366-71, 2001). We now present a new shot descriptor technique which improves the previous search results by using a simple, yet efficient, algorithm, based on the information contained in consecutive fra…
A Fast Anchor Person Searching Scheme in News Sequences
In this paper we address the problem of seeking anchor person shots in news sequences. This can be useful since usually this kind of scenes contain important and reusable information such as interviews. The proposed technique is based on our a priori knowledge of the editing techniques used in news sequences.
The indexing of persons in news sequences using audio-visual data
We describe a video indexing system that automatically searches for a specific person in a news sequence. The proposed approach combines audio and video confidence values extracted from speaker and face recognition analysis. The system also incorporates a shot selection module that seeks for anchors, where the person on the scene is likely speaking. The system has been extensively tested on several news sequences with very good recognition rates.
Fully automatic face recognition system using a combined audio-visual approach
This paper presents a novel audio and video information fusion approach that greatly improves automatic recognition of people in video sequences. To that end, audio and video information is first used independently to obtain confidence values that indicate the likelihood that a specific person appears in a video shot. Finally, a post-classifier is applied to fuse audio and visual confidence values. The system has been tested on several news sequences and the results indicate that a significant improvement in the recognition rate can be achieved when both modalities are used together.
Role for Chromatin Remodeling Factor Chd1 in Learning and Memory
Precise temporal and spatial regulation of gene expression in the brain is a prerequisite for cognitive processes such as learning and memory. Epigenetic mechanisms that modulate the chromatin structure have emerged as important regulators in this context. While posttranslational modification of histones or the modification of DNA bases have been examined in detail in many studies, the role of ATP-dependent chromatin remodeling factors (ChRFs) in learning- and memory-associated gene regulation has largely remained obscure. Here we present data that implicate the highly conserved chromatin assembly and remodeling factor Chd1 in memory formation and the control of immediate early gene (IEG) r…