NOT Logic Functions Research Articles

GHOST-NOT and GHOST-YES: Two programs for generating high-speed biosensors with randomized oligonucleotide binding sites with NOT or YES Boolean logic functions based on experimentally validated algorithms.

High-speed allosteric hammerhead ribozymes can be engineered to distinguish well between a perfectly matching effector and the nucleic acid sequences with a few mismatches under physiologically relevant conditions. Such ribozymes can be designed to control the expression of exogenous mRNAs and can be used to develop new gene therapies, including anticancer treatments. The in vivo selection of such ribozymes is a complicated and lengthy procedure with no guarantee of success. Thus, in silico selection of high-speed ribozymes can be employed using secondary RNA structure computation based on the partition function of the RNA folding in combination with random search algorithms. This approach has already been proven very accurate in designing allosteric hammerhead ribozymes. Herein, we present two programs for the computational design of allosteric ribozymes sensing randomized oligonucleotides based on the extended version of the hammerhead ribozyme. A Generator for High-speed Oligonucleotide Sensing allosteric ribozymes with NOT logic function (GHOST-NOT) and a Generator for High-speed Oligonucleotide Sensing allosteric ribozymes with YES logic function (GHOST-YES) for computational design of high-speed allosteric ribozymes are described. The allosteric hammerhead ribozymes had a high self-cleavage rate of about 1.8 per minute and were very selective in sensing an effector sequence.

Egg albumen-based biopolymer electrolyte lateral capacitive coupling thin-film transistors on logical operation

Recently, green electronic products are receiving increasing attention from scientists. Here, biodegradable lateral capacitively coupled electric-double-layer (EDL) oxide-based thin-film transistors (TFTs) were fabricated on a flexible paper substrate. The TFTs exhibit good performance due to the extremely high EDL capacitance of the egg albumen based electrolyte. Good transistor performances against mechanical stress were observed. In the coplanar double-gate structure, the high-low level of the different periods is input to the two gates to realize the logical function ‘AND’ operation. Resistor loaded inverters were built, exhibiting full-swing amplitude and high-voltage gain at low operating voltages, and implementing ‘NOT’ logic function. And the inverters were used to realize the conversion of the noise signal to the two-bit output. Therefore, the proposed lateral capacitively coupled TFTs may have potential applications in low-cost green portable logic computing devices. Laterally capacitively coupled TFTs were fabricated on a paper substrate by using egg albumen solid electrolyte film as a gate dielectric. The TFTs exhibit good performance due to the extremely high EDL capacitance of the egg albumen based electrolyte. AND logic operations and NOT logic functions are implemented on TFTs based on this lateral planar coupling structure. • Thin-film transistors (TFTs) with lateral capacitive coupling are fabricated on a paper substrate using natural egg albumen as gate dielectric. •These egg albumen-based flexible TFTs can implement logic operation functions under low voltage conditions and have excellent noise immunity. •The proton movement mechanism of lateral capacitive coupling in an external electric field is explained in our coplanar-gate structure of TFTs.

Spin Logic Devices via Electric Field Controlled Magnetization Reversal by Spin-Orbit Torque

We describe a spin logic device with controllable magnetization switching of perpendicularly magnetized ferromagnet/heavy metal structures on a ferroelectric (1- <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${x}$ </tex-math></inline-formula> ) [Pb(Mg <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1/3</sub> Nb <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2/3</sub> )O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> ]- <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">x</i> [PbTiO3] (PMN-PT) substrate using current-induced spin-orbit torque. The devices were operated without an external magnetic field and controlled by voltages as low as 10 V applied across the PMN-PT substrate, which is much lower compared with the previous reports (500 V). The deterministic switching with smaller voltage was realized from the virgin state of the PMN-PT. The ferroelectric simulation shows the unsaturated minor loop exhibits obvious asymmetries in the polarizations. Larger polarization can be induced from the initial ferroelectric state, while it is difficult for opposite polarization. The XNOR, AND, NAND, and NOT logic functions were demonstrated by the deterministic magnetization switching from the interaction between the spin-orbit torque and electric field at the PMN-PT/Pt interface. The nonvolatile spin logic scheme in this letter is simple, scalable, and programmable, which are favorable in the logic-in-memory design with low energy consumption.

Ultra-compact all-optical phase-controlled NAND, OR, XOR, XNOR, and NOT multi-function logic gate

We propose a novel multi-function logic gate in order to attain all NAND, OR, XOR, XNOR, and NOT logic functions in a single structure with controlling the phase of input lights. Beam propagation analysis illustrates that the highest insertion loss of structure is − 0.05 dB in whole C-band. The output on–off logic level contrast ratio for NAND, OR, XOR, XNOR, and NOT logic functions are 28.2, 28.2, 30.2, 30.2, and 30.2 dB, respectively. The structure which is composed of one multimode interference region with ultra-small size of 1.5 µm × 12.2 µm is a promising candidate for ultra-compact systems.

MMI-Based Simultaneous All-Optical XOR–NAND–OR and XNOR–NOT Multilogic Gate for Phase-Based Signals

We propose a novel design to simultaneously access various optical logic functions from different output ports. Logical values of inputs and outputs are defined in phase and intensity area of light, respectively. The proposed structure is composed of one multimode interference waveguide with the ultrasmall size of 2.5 μm × 21 μm. Three output ports of proposed structure offer XOR, NAND, and OR logic functions. In addition, XNOR and NOT logic gates are realized by considering some changes in the conditions. Beam propagation method has been utilized to accomplish the simulations of light propagation. Simulation results of structure in whole C-band show that the maximum insertion loss is -0.14 dB and the least contrast ratio achieved for XOR, NAND, OR, XNOR, and NOT logic functions are 26, 24.7, 25.9, 26, and 25 dB, respectively.

Ultrahigh Speed Reconfigurable Logic Operations Based on Single Semiconductor Optical Amplifier

We demonstrate an optical gate architecture using a single SOA to perform AND, OR and NOT logic functions. Simple reconfigurable all-optical logic operations are implemented using RZ modulated signals at 40 Gb/s. Contrast ratio and extinction ratio values have been analysed for the different types of logic gates. Maximum extinction ratio and contrast ratio achieved are 19dB and 17.2 dB respectively. Simple structure and potential for integration makes this architecture an interesting approach in photonic computing and optical signal processing.

Optical logic operations with self-pumped phase-conjugation output in photorefractive materials

By using the induced and erasable self-pumped phase-conjugation in photorefractive materials, OR, NOR and NOT logic functions can be performed. The signal-to-noise (logic 1/0) ratio at the output is extremely large. Such logic operations can be combined to implement more complex functions or any logic system.