Canal-U

Mon compte

Résultats de recherche

Nombre de programmes trouvés : 5465
Label UNT Vidéocours

le (4m50s)

5.3. Building an array of distances

So using the sequences of homologous gene between several species, our aim is to reconstruct phylogenetic tree of the corresponding species. For this, we have to comparesequences and compute distances between these sequences and we have seen last week how we were able to measure the similarity between sequences and we can use this similarity as a measureof distance between sequences. So we will compare pairs of sequences, measure the similarity and store the value of distance, of similarity into what we could call a matrix or an array. Before going further, let's makemore explicit the use of these two terms, they are not equivalentbut some people mix them. The ...
Voir la vidéo
Label UNT Vidéocours

le (4m52s)

5.3. Attacks against the CFS Scheme

In this session, we will have a look at the attacks against the CFS signature scheme. As for public-key encryption, there are two kinds of attacks against signature schemes. First kind of attack is key recovery attacks where an attacker tries to recover the secret key from the knowledge of the public key. These attacks are exactly the same as against the McEliece cryptosystem that you have seen last week. The only difference is the parameters. Here in the signature, we have a small t and a large n but the algorithm ...
Voir la vidéo
Label UNT Vidéocours

le (4m53s)

1.2. At the heart of the cell: the DNA macromolecule

During the last session, we saw how at the heart of the cell there's DNA in the nucleus, sometimes of cells, or directly in the cytoplasm of the bacteria. The DNA is what we call a macromolecule, that is a very long molecule. It's Avery, in 1944, who discovered that the DNA was the support of genetic information. But the scientists who are most well-known for DNA are Francis Crick and James Watson who discovered together, with Maurice Wilkins and Rosalind Franklin, in 1953, the structure of DNA, the famous double helix, the two strands. Here are Crick and Watson explaining on a very crude wire model far away ...
Voir la vidéo

 
FMSH
 
Facebook Twitter Google+
Mon Compte