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Chemistry as an unconventional computing medium presently lacks a systematic approach to gather, store, and sort data over time. To build more complicated systems in chemistries, the ability to look at data in the past would be a valuable tool to perform complex calculations. In this paper we present the first implementation of a chemical delay line providing information storage that can reliably capture information over an extended period of time. The delay line is capable of parallel operations in a single instruction, multiple data (SIMD) fashion.

Using mass action and Michaelis-Menten kinetics, we describe the chemical delay line implementation featuring enzymes acting as a means to reduce copy errors. We also discuss how information is randomly accessible from any element on the delay line. Our work shows how the chemical delay line retains and provides a value from a previous cycle. The system's modularity allows for integration with existing chemical systems. We exemplify the delay line capabilities by integration with a threshold asymmetric signal perceptron to demonstrate how it learns all 14 linearly separable binary functions over a sliding window of size two. The delay line has applications in biomedical diagnosis and treatment, such as smart drug delivery.

As the semiconductor industry strives for downsizing and high speed, it is confronted with increasing scaling uncertainty as devices decrease to the nanoscale. Nano-magnetic logic (NML) is an alternative approach to synthesize the digital logic circuits with high-density and low-power consumption. We introduced an optimal design of content addressable memory (CAM) memory based on perpendicular nano-magnetic logic (pNML). The main aim of this implementation is to synthesize CAM memory in terms of latency and other design parameters. The implementation of the design is a multilayer approach, which is optimal. The synthesis approach and optimization are perfectly scalable across layout construction of designs. Here a new logic gate in pNML technology is designed which is mainly used for matching of two input numbers. According to insight, both memory unit and a matching unit in the pNML are introduced in the state-of-the-artwork for the first time to synthesize design in high-speed pNML application. MAGCAD tool is used for the design of all the proposed pNML layouts.

Cloud computing allows for access to ubiquitous data storage and powerful computing resources through the use of web services. There are major concerns, however, with data security, reliability, and availability in the cloud. In this paper, we address these concerns by introducing a novel security mechanism for secure and fault-tolerant cloud information storage. The information storage model follows the RAID (Redundant Array of Independent Disks) concept by considering cloud service providers as independent virtual disk drives. As such, the model utilizes multiple cloud service providers as a cloud cluster for information storage, and a service directory for management of the cloud clusters including service query, key management, and cluster restoration. Our approach not only supports maintaining the confidentiality of the stored data, but also ensures that the failure or compromise of an individual cloud provider in a cloud cluster will not result in a compromise of the overall data set. To ensure a correct design, we present a formal model of the security mechanism using hierarchical colored Petri nets (HCPN), and verify some key properties of the model using model checking techniques.

Microtubules (MTs) are cytoskeletal protein polymers orchestrating a host of important cellular functions including, but not limited to, cell support, cell division, cell motility and cell transport. We construct a toy-model of the MT lattice composed of classical vector Ising spins (dipole moments) representing the tubulin molecules, the building block of MTs. Nearest-neighbor (NN) and next-nearest-neighbor (NNN) interactions are considered within an anisotropic dielectric medium. As a consequence of the helical topology, certain spin orientations render the lattice frustrated with NN ferroelectric and NNN antiferroelectric bonds. Mapping the problem to a 2D Ising model and employing Monte Carlo methods we find that frozen clusters of spins exist at human physiological temperatures. This suggests a novel biological mechanism for storing information in living organisms, whereby the classical tubulin spin states become information bits and information gets stored in MTs in a way that is robust to thermal fluctuations.

Quantum computing and quantum communication have become the most popular research topic. Nitrogen-vacancy (NV) centers in diamond have been shown the great advantage of implementing quantum information processing. The generation of entanglement between NV centers represents a fundamental prerequisite for all quantum information technologies. In this paper, we propose a scheme to realize the high-fidelity storage and extraction of quantum entanglement information based on the NV centers at room temperature. We store the entangled information of a pair of entangled photons in the Bell state into the nuclear spins of two NV centers, which can make these two NV centers entangled. And then we illuminate how to extract the entangled information from NV centers to prepare on-demand entangled states for optical quantum information processing. The strategy of engineering entanglement demonstrated here maybe pave the way towards a NV center-based quantum network.

Porphyrinic molecules have been shown to be viable candidates for a molecular-based information storage medium on the basis of redox activity. An optimal redox-based information storage medium requires a large charge density in the molecular footprint on the anchoring substrate. The use of dimeric versus monomeric architectures affords one route to achieving increased charge density without sacrificing surface cross sectional area. Towards this goal, a series of zinc and cobalt containing porphyrin dimers has been prepared and characterized. The interporphyrin linkages in the dimers include p-phenylene, ethynyl, 1,4-butadiynyl, and ethynylphenylethynyl joining porphyrin meso-positions; Crossley-type fusion bridging porphyrin β-positions, and Osuka-type triple fusions bridging one meso- and two β-positions. The electrochemical features of each dimer have been evaluated.

Classical conditioning rapidly produces enduring frequency-specific modification of receptive fields (RF) in the auditory cortex (ACx) which favor the processing of the frequency of the conditioned stimulus (CS). Responses to the CS are increased whereas responses to the pre-training best frequency (BF) and other frequencies are decreased; tuning is often completely shifted so that the frequency of the CS becomes the BF. Such plasticity is observed both for single tone and for two-tone discrimination training. CS-specific RF plasticity may be reversed by extinction training. Sensitization training produces only general increases in responsiveness. Habituation produces frequency-specific decreased responses in the RF. Tuning shifts similar to those produced by conditioning can be produced by iontophoretic application of muscarinic agonists or cholinesterase antagonists to the ACx and pairing one tone with application of ACh to the auditory cortex produces receptive field plasticity which is specific to the frequency of the paired tone. Dual medial geniculate (MG) input to the auditory cortex consists of a frequency-specific non-plastic nucleus (MGv) and a broadly-tuned plastic nucleus (MGm). A preliminary model of receptive field plasticity and behavioral learning is presented. It links MGv and MGm influences on auditory cortex with cholinergic neuromodulation, and makes several predictions, some of which have recently been supported.