@inproceedings{11929, abstract = {Broder et al.'s [3] shingling algorithm and Charikar's [4] random projection based approach are considered "state-of-the-art" algorithms for finding near-duplicate web pages. Both algorithms were either developed at or used by popular web search engines. We compare the two algorithms on a very large scale, namely on a set of 1.6B distinct web pages. The results show that neither of the algorithms works well for finding near-duplicate pairs on the same site, while both achieve high precision for near-duplicate pairs on different sites. Since Charikar's algorithm finds more near-duplicate pairs on different sites, it achieves a better precision overall, namely 0.50 versus 0.38 for Broder et al.'s algorithm. We present a combined algorithm which achieves precision 0.79 with 79% of the recall of the other algorithms.}, author = {Henzinger, Monika H}, booktitle = {29th Annual International ACM SIGIR Conference on Research and Development in Information Retrieval}, location = {Seattle, WA, United States}, pages = {284--291}, publisher = {Association for Computing Machinery}, title = {{Finding near-duplicate web pages: A large-scale evaluation of algorithms}}, doi = {10.1145/1148170.1148222}, year = {2006}, } @article{1462, abstract = {A Fourier transform technique is introduced for counting the number of solutions of holomorphic moment map equations over a finite field. This technique in turn gives information on Betti numbers of holomorphic symplectic quotients. As a consequence, simple unified proofs are obtained for formulas of Poincaré polynomials of toric hyperkähler varieties (recovering results of Bielawski-Dancer and Hausel-Sturmfels), Poincaré polynomials of Hubert schemes of points and twisted Atiyah-Drinfeld-Hitchin-Manin (ADHM) spaces of instantons on ℂ2 (recovering results of Nakajima-Yoshioka), and Poincaré polynomials of all Nakajima quiver varieties. As an application, a proof of a conjecture of Kac on the number of absolutely indecomposable representations of a quiver is announced.}, author = {Tamas Hausel}, journal = {PNAS}, number = {16}, pages = {6120 -- 6124}, publisher = {National Academy of Sciences}, title = {{Betti numbers of holomorphic symplectic quotients via arithmetic Fourier transform}}, doi = {10.1073/pnas.0601337103}, volume = {103}, year = {2006}, } @article{1461, abstract = {This note proves combinatorially that the intersection pairing on the middle-dimensional compactly supported cohomology of a toric hyperkähler variety is always definite, providing a large number of non-trivial L 2 harmonic forms for toric hyperkähler metrics on these varieties. This is motivated by a result of Hitchin about the definiteness of the pairing of L 2 harmonic forms on complete hyperkähler manifolds of linear growth.}, author = {Tamas Hausel and Swartz, Edward}, journal = {Proceedings of the American Mathematical Society}, number = {8}, pages = {2403 -- 2409}, publisher = {American Mathematical Society}, title = {{Intersection forms of toric hyperkähler varieties}}, doi = {10.1090/S0002-9939-06-08248-7}, volume = {134}, year = {2006}, } @article{1715, abstract = {Background: Cell-to-cell communication at the synapse involves synaptic transmission as well as signaling mediated by growth factors, which provide developmental and plasticity cues. There is evidence that a retrograde, presynaptic transforming growth factor-β (TGF-β) signaling event regulates synapse development and function in Drosophila. Results: Here we show that a postsynaptic TGF-β signaling event occurs during larval development. The type I receptor Thick veins (Tkv) and the R-Smad transcription factor Mothers-against-dpp (Mad) are localized postsynaptically in the muscle. Furthermore, Mad phosphorylation occurs in regions facing the presynaptic active zones of neurotransmitter release within the postsynaptic subsynaptic reticulum (SSR). In order to monitor in real time the levels of TGF-β signaling in the synapse during synaptic transmission, we have established a FRAP assay to measure Mad nuclear import/export in the muscle. We show that Mad nuclear trafficking depends on stimulation of the muscle. Conclusions: Our data suggest a mechanism linking synaptic transmission and postsynaptic TGF-β signaling that may coordinate nerve-muscle development and function.}, author = {Dudu, Veronika and Bittig, Thomas and Entchev, Eugeni and Kicheva, Anna and Julicher, Frank and González Gaitán, Marcos}, journal = {Current Biology}, number = {7}, pages = {625 -- 635}, publisher = {Cell Press}, title = {{Postsynaptic mad signaling at the Drosophila neuromuscular junction}}, doi = {10.1016/j.cub.2006.02.061}, volume = {16}, year = {2006}, } @article{1745, abstract = {SiGe islands grown by deposition of 10 monolayers of Ge on Si(0 0 1) at 740 °C were investigated by using a combination of selective wet chemical etching and atomic force microscopy. The used etchant, a solution consisting of ammonium hydroxide and hydrogen peroxide, shows a high selectivity of Ge over SixGe1-x and is characterized by relatively slow etching rates for Si-rich alloys. By performing successive etching experiments on the same sample area, we are able to gain a deeper insight into the lateral displacement the islands undergo during post growth annealing.}, author = {Georgios Katsaros and Rastelli, Armando and Stoffel, Mathieu and Isella, Giovanni and Von Känel, Hans and Bittner, Alexander M and Tersoff, Jerry and Denker, Ulrich and Schmidt, Oliver G and Costantini, Giovanni and Kern, Klaus}, journal = {Surface Science}, number = {12}, pages = {2608 -- 2613}, publisher = {Elsevier}, title = {{Investigating the lateral motion of SiGe islands by selective chemical etching}}, doi = {10.1016/j.susc.2006.04.027}, volume = {600}, year = {2006}, }