Terrestrial and aquatic gastropods from the upper Eocene (Priabonian) Zalumah Formation in the Salalah region of the Sultanate of Oman are described. The assemblages reflect the composition of the continental mollusc fauna of the Palaeogene of Arabia, which, at that time, formed parts of the southeastern Tethys coast. Several similarities with European faunas are observed at the family level, b...

We give an unconditional proof of the André-Oort conjecture for arbitrary products of modular curves. We establish two generalizations. The first includes the Manin-Mumford conjecture for arbitrary products of elliptic curves defined over Q as well as Lang’s conjecture for torsion points in powers of the multiplicative group. The second includes the ManinMumford conjecture for abelian varieties...

This paper investigates the connexion between the Kannan-Lipton Orbit Problem and the polynomial invariant generator algorithm PILA based on eigenvectors computation. Namely, we reduce the problem of generating linear and polynomial certificates of non-reachability for the Orbit Problem for linear transformations with coefficients in Q to the generalized eigenvector problem. Also, we prove the ...

Bjorn Poonen discussed the “recognition problem” for finitely generated rings (and fields). That is, given two finitely generated commutative rings A and B, presented in terms of generators and relations, is there a decision procedure to determine whether or not these rings are isomorphic (this being, one would think, a basic issue for algebraic geometry!). Of course, if one drops the requireme...

This field study investigated the distribution of the freshwater snails of the family Ampullariidae in 18 provinces of Thailand. The introduced Pomacea canaliculata has wide distribution in the studied provinces. Pila angelica, P. ampullacea and P. pesmei still have limited distribution. Pila polita, which is absent in the south, now can be found in Phangnga, a southern province of Thailand. Mo...

We give an unconditional proof of the André-Oort conjecture for arbitrary products of modular curves. We establish two generalizations. The first includes the Manin-Mumford conjecture for arbitrary products of elliptic curves defined over Q as well as Lang’s conjecture for torsion points in powers of the multiplicative group. The second includes the Manin-Mumford conjecture for abelian varietie...

Abstract Testicular development and function rely on interactions between somatic cells the germline, but similar to other organs, regenerative capacity declines in aging disease. Whether adult testis maintains a reserve progenitor population remains uncertain. Here, we characterize recently identified mouse interstitial expressing transcription factor Tcf21. We found that TCF21 lin are bipoten...