Novel chromatin regulatory activity of ESCO2 in cancer and neural development

ESCO2 has a well characterized role in the stabilization of the cohesin ring through its acetyltransferase activity. Quantitative PCR studies comparing RNA from tissue collected from ependymoma biopsies and tissue from non-tumor brain, show an increased level of ESCO2 transcription in ependymoma. High levels of ESCO2 protein expression in ependymoma tissue samples were confirmed via immunostaining and confocal microscopy. ESCO2 expression ordinarily peaks during mitosis in order to stabilize the cohesin ring, and is reported to increase the rate of replication. However, some ESCO2 expressing cells are not mitotic in these tumors. Because of the detrimental effects of deletion of ESCO2 on neural development and its high expression in ependymoma, a type of tumor that exhibits many characteristics of primitive neural cells, the current study sought to investigate the broader role of ESCO2 in primitive neural cells. Studies carried out in Zebrafish were performed to explore the possibility of an additional role for ESCO2 as a regulator of neural development. QPCR on Zebrafish embryos at developmental timepoints indicated that ESCO2 expression was highest 48 hours post-fertilization, and then declined thereafter. Confocal microscopy on transgenic NeuroD-EGFP embryos at 24-96 hpf confirmed that the proportion of ESCO2 positive brain cells decreases by 96 hpf, that non-mitotic ESCO2 expressing cells decline, and that 48 hpf appear to display a unique pattern of ESCO2 staining associated with the 4th ventricle. Using FACS and subsequent chromatin immunoprecipitation studies, Esco2- bound chromatin was isolated from NT2 neural progenitor cells and NeuroD-EGFP+ transgenic zebrafish, and utilized to identify novel sites of Esco2 regulation. The data obtained suggests an additional layer of neural regulatory activity that may be unrelated to the reported SMC3 acetyltransferase activity of ESCO2, and that could play a role in neural pathologies such as cancer. Esco2 may be a novel therapeutic target for ependymoma

Hydrogen safety Progress report no. 6, 1 Apr. - 30 Jun. 1965

Hydrogen safety hazards, storage, and handling - Hydrogen plume studies to determine quantity-distance criteria and guidelines for optimum placement of hydrogen detector

Hydrogen safety Progress report no. 7 1 Jul. - 30 Sep. 1965

Performance characteristics of two console-type hydrogen gas detectors sampling by diffusion and convectio

Table of contents and editorial information for Vol. 8, no. [4], Fall 1981.

Table of contents and editorial information for Vol. 8, no. [4], Fall 1981. [This issue mislabeled as vol. 8, no. 3.

Educational Considerations, vol. 8(4) Full Issue

Educational Considerations, vol. 8(4) Fall 1981 - Full issu

Quantum Estimation of Parameters of Classical Spacetimes

We describe a quantum limit to measurement of classical spacetimes. Specifically, we formulate a quantum Cramer-Rao lower bound for estimating the single parameter in any one-parameter family of spacetime metrics. We employ the locally covariant formulation of quantum field theory in curved spacetime, which allows for a manifestly background-independent derivation. The result is an uncertainty relation that applies to all globally hyperbolic spacetimes. Among other examples, we apply our method to detection of gravitational waves using the electromagnetic field as a probe, as in laser-interferometric gravitational-wave detectors. Other applications are discussed, from terrestrial gravimetry to cosmology.Comment: 23 pages. This article supersedes arXiv:1108.522

Layer by layer generation of cluster states

Cluster states can be used to perform measurement-based quantum computation. The cluster state is a useful resource, because once it has been generated only local operations and measurements are needed to perform universal quantum computation. In this paper, we explore techniques for quickly and deterministically building a cluster state. In particular we consider generating cluster states on a qubus quantum computer, a computational architecture which uses a continuous variable ancilla to generate interactions between qubits. We explore several techniques for building the cluster, with the number of operations required depending on whether we allow the ability to destroy previously created controlled-phase links between qubits. In the case where we can not destroy these links, we show how to create an n x m cluster using just 3nm -2n -3m/2 + 3 operations. This gives more than a factor of 2 saving over a naive method. Further savings can be obtained if we include the ability to destroy links, in which case we only need (8nm-4n-4m-8)/3 operations. Unfortunately the latter scheme is more complicated so choosing the correct order to interact the qubits is considerably more difficult. A half way scheme, that keeps a modular generation but saves additional operations over never destroying links requires only 3nm-2n-2m+4 operations. The first scheme and the last scheme are the most practical for building a cluster state because they split up the generation into the repetition of simple sections.Comment: 16 pages, 11 figure

Table of contents and editorial information for Vol. 9, no. 1, Winter 1982

Table of contents and editorial information for Vol. 9, no. 1, Winter 198

Table of contents and editorial information for Vol. 9, no. 2, Spring 1982

Table of contents and editorial information for Vol. 9, no. 2, Spring 198