Realization of Complex Logic Operations at the Nanoscale

Gene therapy and transgenic research have advanced quickly in recent years due to the development of CRISPR technology. The rapid development of CRISPR technology has been largely benefited by chemical engineering. Firstly, chemical or synthetic substance enables spatiotemporal and conditional control of Cas9 or dCas9 activities. It prevents the leaky expression of CRISPR components, as well as minimizes toxicity and off-target effects. Multi-input logic operations and complex genetic circuits can also be implemented via multiplexed and orthogonal regulation of target genes. Secondly, rational chemical modifications to the sgRNA enhance gene editing efficiency and specificity by improving sgRNA stability and binding affinity to on-target genomic loci, and hence reducing off-target mismatches and systemic immunogenicity. Chemically-modified Cas9 mRNA is also more active and less immunogenic than the native mRNA. Thirdly, nonviral vehicles can circumvent the challenges associated with viral packaging and production through the delivery of Cas9-sgRNA ribonucleoprotein complex or large Cas9 expression plasmids. Multi-functional nanovectors enhance genome editing in vivo by overcoming multiple physiological barriers, enabling ligand-targeted cellular uptake, and blood-brain barrier crossing. Chemical engineering can also facilitate viral-based delivery by improving vector internalization, allowing tissue-specific transgene expression, and preventing inactivation of the viral vectors in vivo. This review aims to discuss how chemical engineering has helped improve existing CRISPR applications and enable new technologies for biomedical research. The usefulness, advantages, and molecular action for each chemical engineering approach are also highlighted.

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Digital logic gates in soft, conductive mechanical metamaterials

Nature Communications ◽

10.1038/s41467-021-21920-y ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Charles El Helou ◽

Philip R. Buskohl ◽

Christopher E. Tabor ◽

Ryan L. Harne

Keyword(s):

Integrated Circuits ◽

Electronic Materials ◽

Polymer Networks ◽

Conductive Polymer ◽

Network Connectivity ◽

Logic Gates ◽

Boolean Logic ◽

Digital Logic ◽

Mechanical Metamaterials ◽

Logic Operations

AbstractIntegrated circuits utilize networked logic gates to compute Boolean logic operations that are the foundation of modern computation and electronics. With the emergence of flexible electronic materials and devices, an opportunity exists to formulate digital logic from compliant, conductive materials. Here, we introduce a general method of leveraging cellular, mechanical metamaterials composed of conductive polymers to realize all digital logic gates and gate assemblies. We establish a method for applying conductive polymer networks to metamaterial constituents and correlate mechanical buckling modes with network connectivity. With this foundation, each of the conventional logic gates is realized in an equivalent mechanical metamaterial, leading to soft, conductive matter that thinks about applied mechanical stress. These findings may advance the growing fields of soft robotics and smart mechanical matter, and may be leveraged across length scales and physics.

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Stability and Manoeuvrability Simulation of a Semi-Autonomous Submarine Free-Running Model SUBOFF with an Autopilot System

Applied Sciences ◽

10.3390/app11010410 ◽

2021 ◽

Vol 11 (1) ◽

pp. 410

Author(s):

Yu-Hsien Lin ◽

Yu-Ting Lin ◽

Yen-Jun Chiu

Keyword(s):

Optimal Control ◽

Experimental Tests ◽

Degree Of Freedom ◽

Line Of Sight ◽

Pd Controller ◽

Free Running ◽

Simulation Results ◽

Guidance Algorithm ◽

Logic Operations ◽

Six Degree Of Freedom

On the basis of a full-appendage DARPA SUBOFF model (DTRC model 5470), a scale (λ = 0.535) semi-autonomous submarine free-running model (SFRM) was designed for testing its manoeuvrability and stability in the constrained water. Prior to the experimental tests of the SFRM, a six-degree-of-freedom (6-DOF) manoeuvre model with an autopilot system was developed by using logic operations in MATLAB. The SFRM’s attitude and its trim polygon were presented by coping with the changes in mass and trimming moment. By adopting a series of manoeuvring tests in empty tanks, the performances of the SFRM were introduced in cases of three sailing speeds. In addition, the PD controller was established by considering the simulation results of these manoeuvring tests. The optimal control gains with respect to each manoeuvring test can be calculated by using the PID tuner in MATLAB. Two sets of control gains derived from the optimal characteristics parameters were compared in order to decide on the most appropriate PD controller with the line-of-sight (LOS) guidance algorithm for the SFRM in the autopilot simulation. Eventually, the simulated trajectories and course angles of the SFRM would be illustrated in the post-processor based on the Cinema 4D modelling.

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DNA-based constitutional dynamic networks as functional modules for logic gates and computing circuit operations

Chemical Science ◽

10.1039/d1sc01098k ◽

2021 ◽

Vol 12 (15) ◽

pp. 5473-5483

Author(s):

Zhixin Zhou ◽

Jianbang Wang ◽

R. D. Levine ◽

Francoise Remacle ◽

Itamar Willner

Keyword(s):

Nucleic Acid ◽

Dynamic Networks ◽

Dynamic Network ◽

Logic Gates ◽

Functional Modules ◽

Logic Operations

A nucleic acid-based constitutional dynamic network (CDN) provides a single functional computational module for diverse input-guided logic operations and computing circuits.

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A 1T2C FeCAP-Based In-Situ Bitwise X(N)OR Logic Operation with Two-Step Write-Back Circuit for Accelerating Compute-In-Memory

Micromachines ◽

10.3390/mi12040385 ◽

2021 ◽

Vol 12 (4) ◽

pp. 385

Author(s):

Qiao Wang ◽

Donglin Zhang ◽

Yulin Zhao ◽

Chao Liu ◽

Qiao Hu ◽

...

Keyword(s):

Nonvolatile Memory ◽

High Reliability ◽

Charge Sharing ◽

Operation Speed ◽

Sharing Function ◽

Logic Operations ◽

A Charge ◽

Process Compatibility ◽

Ferroelectric Capacitors

Ferroelectric capacitors (FeCAPs) with high process compatibility, high reliability, ultra-low programming current and fast operation speed are promising candidates to traditional volatile and nonvolatile memory. In addition, they have great potential in the fields of storage, computing, and memory logic. Nevertheless, effective methods to realize logic and memory in FeCAP devices are still lacking. This study proposes a 1T2C FeCAP-based in situ bitwise X(N)OR logic based on a charge-sharing function. First, using the 1T2C structure and a two-step write-back circuit, the nondestructive reading is realized with less complexity than the previous work. Second, a method of two-line activation is used during the operation of X(N)OR. The verification results show that the speed, area and power consumption of the proposed 1T2C FeCAP-based bitwise logic operations are significantly improved.

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