Multiplexed Holographic Data Storage in Bacteriorhodopsin

High density optical data storage, driven by the information revolution, remains at the forefront of current research areas. Much of the current research has focused on photorefractive materials (SBN and LiNbO3) and polymers, despite various problems with expense, durability, response time and retention periods. Photon echo techniques, though promising, are questionable due to the need for cryogenic conditions. Bacteriorhodopsin (BR) films are an attractive alternative recording medium. Great strides have been made in refining BR, and materials with storage lifetimes as long as 100 days have recently become available. The ability to deposit this robust polycrystalline material as high quality optical films suggests the use of BR as a recording medium for commercial optical disks. Our own recent research has demonstrated the suitability of BR films for real time spatial filtering and holography. We propose to fully investigate the feasibility of performing holographic mass data storage in BR. Important aspects of the problem to be investigated include various data multiplexing techniques (e.g. angle- amplitude- and phase-encoded multiplexing, and in particular shift-multiplexing), multilayer recording techniques, SLM selection and data readout using crossed polarizers for noise rejection. Systems evaluations of storage parameters, including access times, memory refresh constraints, erasure, signal-to-noise ratios and bit error rates, will be included in our investigations

Determination of technological parameters of saturated composites based on SiC by means of a model liquid

The paper describes a method for determining technological parameters of the formation process of saturated composites based on SiC by applying the theory of dynamic similarity. Empirical relations have been presented in terms of hydraulic analysis of the saturated liquid flow (liquid metal) and determination of the saturated composite density depending on the technological parameters of its formation process: saturation time and pressure. Adopting the method for determining the density of silumin composites reinforced with silicon carbide by means of Wood’s metal as a model liquid has been described. Microscope images of the composite structure have been shown after filling it with the model liquid. Remarks have been made on the application of the method

Co-formulation of the rF1V plague vaccine with depot-formulated cytokines enhances immunogenicity and efficacy to elicit protective responses against aerosol challenge in mice

This study evaluated a depot-formulated cytokine-based adjuvant to improve the efficacy of the recombinant F1V (rF1V) plague vaccine and examined the protective response following aerosol challenge in a murine model. The results of this study showed that co-formulation of the Alhydrogel-adsorbed rF1V plague fusion vaccine with the depot-formulated cytokines recombinant human interleukin 2 (rhuIL-2) and/or recombinant murine granulocyte macrophage colony-stimulating factor (rmGM-CSF) significantly enhances immunogenicity and significant protection at lower antigen doses against a lethal aerosol challenge. These results provide additional support for the co-application of the depot-formulated IL-2 and/or GM-CSF cytokines to enhance vaccine efficacy

Fundamental Science Investigations to Develop a 6-MV Laser Triggered Gas Switch for ZR: First Annual Report.

In October 2005, an intensive three-year Laser Triggered Gas Switch (LTGS) development program was initiated to investigate and solve observed performance and reliability issues with the LTGS for ZR. The approach taken has been one of mission-focused research: to revisit and reassess the design, to establish a fundamental understanding of LTGS operation and failure modes, and to test evolving operational hypotheses. This effort is aimed toward deploying an initial switch for ZR in 2007, on supporting rolling upgrades to ZR as the technology can be developed, and to prepare with scientific understanding for the even higher voltage switches anticipated needed for future high-yield accelerators. The ZR LTGS was identified as a potential area of concern quite early, but since initial assessments performed on a simplified Switch Test Bed (STB) at 5 MV showed 300-shot lifetimes on multiple switch builds, this component was judged acceptable. When the Z{sub 20} engineering module was brought online in October 2003 frequent flashovers of the plastic switch envelope were observed at the increased stresses required to compensate for the programmatically increased ZR load inductance. As of October 2006, there have been 1423 Z{sub 20} shots assessing a variety of LTGS designs. Numerous incremental and fundamental switch design modifications have been investigated. As we continue to investigate the LTGS, the basic science of plastic surface tracking, laser triggering, cascade breakdown, and optics degradation remain high-priority mission-focused research topics. Significant progress has been made and, while the switch does not yet achieve design requirements, we are on the path to develop successively better switches for rolling upgrade improvements to ZR. This report summarizes the work performed in FY 2006 by the large team. A high-level summary is followed by detailed individual topical reports

Specification of a location for opted port logistics center in a given area using the method of operational research

This paper is focused on area identification to find a proper location for the specific port logistic center in a certain territory by applying the particular method of operational research. Graph theory offers a useful tool for solving such problems in transportation infrastructure development. The type of the network optimization technique depends on problem definition. In the first chapter, we have explained some of the algorithms often applied for similar purposes. In this case, the focus is on Minimum Spanning Three algorithm. Based on well-known Prim’s and Kruskal’s algorithms, some modifications are introduced, to improve the processing speed and memory consumption. The next four chapters describe individual parameters, perspectives, requirements, and financing details for building new combined transport terminals as well as a planned port logistics center. The subsequent, the most important, chapter presents the model example for specifying the proper location of a given port logistics center when using the method of operational research

Impact of Volume Breakdown on Surface Flashover in High Pressure SF6SF_{6}

We investigate the pulsed flashover voltage of dielectric samples at up to 4 bar $SF_{6}$ in the simultaneous presence of a high current (>10 kA, ∼20 microsecond pulse) volume discharge nearby. The chosen distance, ∼7 cm, between surface and volume breakdown is consistent with conditions found in the Sandia-Z-machine type rimfire switch. For a flashover gap distance of 24 mm and a simultaneous excitation within ∼ 5 microseconds, we observe an average reduction in the flashover voltage from 164 kV to 142 kV at 3.7 bar when the volume discharge is turned on. The test setup utilizing a magnetic switching scheme operating at 320 kV and 10 kA is briefly discussed along with the breakdown properties and the spectral characterization of the volume/surface flashover discharge plasma. In general, UV light propagates relatively unattenuated for wavelengths >160 nm in the high pressure $SF_{6}$ from the volume discharge to the dielectric surface, setting up conditions which are conducive to photoelectron emission from the dielectric

Spread-space spread-spectrum technique for secure multiplexing

A novel technique for multiplexing complex images is proposed in which each image may be demultiplexed only if a set of random encryption keys is known. The technique utilizes the ability of the double random phase encoding method to spread a signals’ energy in both the space and the spatial frequency domains in a controlled manner. To multiplex, images are independently encrypted with different phase keys and then superimposed by recording sequentially on the same material. Each image is extracted by using the particular key associated with it. During decryption the energy from the other images is further spread, making it possible to minimize its effects by using suitable filters. Wigner analysis is applied to the technique, and numerical results are presented.Irish Research Council for Science, Engineering and Technologype,la, sp,ke, ab, is, en - kpw6/12/1

Predictors of survival after vaccination in a pneumonic plague model

Background: The need for an updated plague vaccine is highlighted by outbreaks in endemic regions together with the pandemic potential of this disease. There is no easily available, approved vaccine. Methods: Here we have used a murine model of pneumonic plague to examine the factors that maximise immunogenicity and contribute to survival following vaccination. We varied vaccine type, as either a genetic fusion of the F1 and V protein antigens or a mixture of these two recombinant antigens, as well as antigen dose-level and formulation in order to correlate immune response to survival. Results: Whilst there was interaction between each of the variables of vaccine type, dose level and formulation and these all contributed to survival, vaccine formulation in protein-coated microcrystals (PCMCs) was the key contributor in inducing antibody titres. From these data, we propose a cut-off in total serum antibody titre to the F1 and V proteins of 100 µg/mL and 200 µg/mL, respectively. At these thresholds, survival is predicted in this murine pneumonic model to be >90%. Within the total titre of antibody to the V antigen, the neutralising antibody component correlated with dose level and was enhanced when the V antigen in free form was formulated in PCMCs. Antibody titre to F1 was limited by fusion to V, but this was compensated for by PCMC formulation. Conclusions: These data will enable clinical assessment of this and other candidate plague vaccines that utilise the same vaccine antigens by identifying a target antibody titre from murine models, which will guide the evaluation of clinical titres as serological surrogate markers of efficacy