Andrew C. G. Porter

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What Makes Professional Development Effective? Results from a National Sample of Teachers Author(s): Michael S. Garet, Andrew C. Porter, Laura Desimone, Beatrice F. Birman, Kwang Suk Yoon Source: American Educational Research Journal, Vol. 38, No. 4 (Winter, 2001), pp. 915-945 Published by: American Educational Research Association Stable URL:(More)
SUMOylation is essential for cell-cycle regulation in invertebrates; however, its functions during the mammalian cell cycle are largely uncharacterized. Mammals express three SUMO paralogs: SUMO-1, SUMO-2, and SUMO-3 (SUMO-2 and SUMO-3 are 96% identical and referred to as SUMO-2/3). We found that SUMO-2/3 localize to centromeres and condensed chromosomes,(More)
Murine pluripotent stem cells can exist in two functionally distinct states, LIF-dependent embryonic stem cells (ESCs) and bFGF-dependent epiblast stem cells (EpiSCs). However, human pluripotent cells so far seemed to assume only an epiblast-like state. Here we demonstrate that human iPSC reprogramming in the presence of LIF yields human stem cells that(More)
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Professional development plays a key role in addressing the gap between teacher preparation and standards-based reform; it is a key focus of U.S. efforts to improve education. Much of the professional development that is offered to teachers, however, simply does not meet the challenges of the reform movement (Corcoran, 1995; Darling-Hammond, 1995; Hiebert,(More)
Topoisomerase II (topo II) is a major component of mitotic chromosomes and its unique decatenating activity has been implicated in many aspects of chromosome dynamics including DNA replication, transcription, recombination, chromosome condensation and segregation. Of these, chromosome segregation is the most seriously affected by loss of topo II expression(More)
Topoisomerase II (topo II) is a major component of mitotic chromosomes, and its unique decatenating activity has been implicated in many aspects of chromosome dynamics, of which chromosome segregation is the most seriously affected by loss of topo II activity in living cells. There is considerable evidence that topo II plays a role at the centromere(More)
1046 base-pairs (bp) of genomic DNA spanning the first exon of the human alpha/beta-interferon (IFN)-inducible gene 6-16 have been analysed for their role in induction. The whole gene or 5'-flanking deletion derivatives of it were assayed for inducibility in populations of stably transfected mouse cells. 5'-Flanking DNA fragments were assayed for their(More)
We describe a novel gene targeting strategy for the genetic analysis of essential genes in mammalian cells and its use to study the role of the cell cycle control gene CDC2 in human cells. A cell line (HT2-19) was generated in which endogenous CDC2 gene expression and cell viability depend on the presence of an inducer in the growth medium. In the absence(More)
DNA Topoisomerase IIalpha (topoIIalpha) is a DNA decatenating enzyme, abundant constituent of mammalian mitotic chromosomes, and target of numerous antitumor drugs, but its exact role in chromosome structure and dynamics is unclear. In a powerful new approach to this important problem, with significant advantages over the use of topoII inhibitors or RNA(More)