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Neuronal nicotinic acetylcholine receptors (nAChRs) are a family of ligand gated ion channels which are widely distributed in the human brain. Multiple subtypes of these receptors exist, each with individual pharmacological and functional profiles. They mediate the effects of nicotine, a widely used drug of abuse, are involved in a number of physiological(More)
NetFlow data is routinely captured at the border of a many enterprise networks. Although not as rich as full packet capture data, Netflow provides a compact record of the interactions between host pairs on either side of the monitored border. Analysis of this data presents a chal-lange to the security analyst due to its sheer volume. We report preliminary(More)
Many network visualizations make the assumption that an administrator has previously determined the subset of data that should be visualized. Yet the problem remains that if the visualization provides no insight into the network events that warrant further consideration , then the administrator must go back to the data to determine what should be visualized(More)
To extend soft x-ray microscopy to a resolution of order 10 nm or better, we developed a new nanofabrication process for Fresnel zone plate lenses. The new process, based on the double patterning technique, has enabled us to fabricate high quality gold zone plates with 12 nm outer zones. Testing of the zone plate with the full-field transmission x-ray(More)
In recent years the increased proliferation of high coherence X-ray sources such as third generation synchrotrons has helped in the advancement of new forms of microscopy. Among the techniques which are currently being developed, coherent diffractive imaging (CDI) is emerging as one of the most promising, offering the potential of very high resolution(More)
We discuss contrast formation in a propagating x-ray beam. We consider the validity conditions for linear relations based on the transport-of-intensity equation (TIE) and on contrast transfer functions (CTFs). From a single diffracted image, we recover the thickness of a homogeneous object which has substantial absorption and a phase-shift of --0.37 radian.
Open computing environments are under a deluge of network attacks from complex threats. These threats are distributed, decentralized , dynamic, and operate over multiple timescales. Trusted Computing environments provide a means to manage cryptographic identity and authentication operations in the form of static assertions, but were not developed to provide(More)
We demonstrate the first general tabletop EUV coherent microscope that can image extended, non-isolated, non-periodic, objects. By implementing keyhole coherent diffractive imaging with curved mirrors and a tabletop high harmonic source, we achieve improved efficiency of the imaging system as well as more uniform illumination at the sample, when compared(More)
We describe a method for characterizing focused x-ray beams using phase retrieval, with diversity achieved by transversely translating a phase-shifting or absorbing structure close to the beam focus. The required measurements can be taken with an experimental setup that is similar to that already used for fluorescent scan testing. The far-field intensity(More)
We have used coherent X-ray diffraction experiments to characterize both the 1-D and 2-D foci produced by nanofocusing Kirkpatrick-Baez (K-B) mirrors, and we find agreement. Algorithms related to ptychography were used to obtain a 3-D reconstruction of a focused hard X-ray beam waist, using data measured when the mirrors were not optimally aligned.(More)