Recognition and sensing of ions is an important front in supramolecular organic chemistry. One remarkable extension of this kind of work is the application of selective switching processes to logic gate operations. In this study, we have designed selective metal ion chelators for zinc and cadmium ions based on dansylamide fluorophores and dipicolylamine chelators. The zinc complex of a previously reported difluoroboradiazaindacene-bipyridyl derivative was shown to respond anions by an increase in emission intensity. We also discovered a hitherto unknown reaction of difluoroboradiazaindacenes and showed that this reaction can be exploited in a very selective sensing of fluoride ions in acetone solutions. The remarkable chemistry of these boradiazaindacene dyes, especially the bipyridyl derivative, allowed us to propose the first example of a unimolecular &ldquo / molecular subtractor&rdquo / . A single molecule can carry out substraction of binary inputs, when these inputs are fluoride anion and zinc cation.

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Synthetic genetic circuits have revolutionized numerous fields, ranging from academic research and point-of-care diagnostics to disease therapeutics and industrial biomanufacturing. These circuits provide a powerful tool for precise spatiotemporal control over biological and biochemical interactions, thereby enhancing our understanding of these complex systems and expanding their applicability. The last few decades have witnessed a surge in research efforts, both in cell-free and cellular systems. These endeavors include those to improve the sensitivity and specificity of diagnostics and optimize the safety, efficacy, and tunability of existing treatments. This dissertation delves into the exploration of Boolean logic gates in the cell-free realm: the development of a 'Cell-Free Recombinase Integrated Boolean Operating System' (CRIBOS) for expanding the capabilities of cell-free sensing applications. Applications of Boolean logic gates have flourished within cellular systems and animal models. However, a persisting gap in the field is in their exploration within the cell-free system. This deficiency has resulted in a constrained toolkit for studying and applying Boolean logic gates in cell-free settings. Recognizing this limitation in the field and aiming to extend the frontiers of genetic circuits beyond traditional boundaries, I introduce CRIBOS, leveraging the advantages of recombinase, known for its high orthogonality, efficiency, and sensitivity. I designed more than 20 multi-input-multi-output recombinase Boolean logic gates in a cell-free context, from which a set of critical rules crucial for building genetic circuits in the cell-free environment was also established. In addition, integrating allosteric transcription factor (aTF)-based sensors with CRIBOS enabled multiplex environmental sensing within the cell-free environment. Moreover, the CRIBOS system showcased its versatility by facilitating the creation of a biological memory storage device, demonstrating robust functionality with high stability over four months. Implementing CRIBOS not only expands the application of multiplex Boolean logic gates from cellular systems to the cell-free environment but also expands their overall versatility, opening new avenues for the design and application of sophisticated genetic circuits.

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This paper details the design and simulation of a fault-tolerant Quantum-dot Cellular Automata (QCA) NOT gate. A version of the standard NOT gate can be constructed to take advantage to the ability to easily integrate redundant structures into a QCA design. The fault-tolerant characteristics of this inverter are analyzed with QCADesigner v2.0.3 (Windows version) simulation software. These characteristics are then compared with the characteristics of two other non-redundant styles of NOT gates. The redundant version of the gate is more robust than the standard style for the inverter. However, another simple inverter style seems to be even more than this fault-tolerant design. Both versions of the gate will need to be studied further in the future to determine which design is most practical. / Thesis (M.S.)--Wichita State University, College of Engineering, Dept. of Electrical and Computer Engineering / "July 2006." / Includes bibliographic references (leaves 31-33)

Threshold logic gates gaining more importance in recent years due to the significant development in the switching devices. This renewed the interest in synthesis and testing of circuits with threshold logic gates. Two important synthesis considerations of threshold logic circuits are addressed namely, threshold logic function identification and reducing the total number of threshold logic gates required to represent the given boolean circuit description. A fast method to identify the given Boolean function as a threshold logic function with weight assignment is introduced. It characterizes the threshold logic function based on the modified chows parameters which results in drastic reduction in time and complexity. Experiment results shown that the proposed method is at least 10 times faster for each input and around 20 times faster for 7 and 8 input, when comparing with the algorithmic based methods. Similarly, it is 100 times faster for 8 input, when comparing with asummable method. Existing threshold logic synthesis methods decompose the larger input functions into smaller input functions and perform synthesis for them. This results in increase in the number of threshold logic gates required to represent the given circuit description. The proposed implicit synthesis methods increase the size of the functions that can be handled by the synthesis algorithm, thus the number of threshold logic gates required to implement very large input function decreases. Experiment results shown that the reduction in the TLG count is 24% in the best case and 18% on average. An automatic test pattern generation approach for transition faults on a circuit consisting of current mode threshold logic gates is introduced. The generated pattern for each fault excites the maximum propagation delay at the gate (the fault site). This is a high quality ATPG. Since current mode threshold logic gate circuits are pipelined and the combinational depth at each pipeline stage is practically one. It is experimentally shown that the fault coverage for all benchmark circuits is approximately 97%. It is also shown that the proposed method is time efficient.

Conventional methods for diagnosis of human disease are, at times, limited in different regards including time requirement, either experimental or data processing, sensitivity, and selectivity. It is then that a Point of Care Criteria, which considers the true utility and usefulness of the device, is employed to propose new diagnostic devices capable of overcoming the aforementioned shortcomings of conventional tools. Nucleic acid, characterized for its predictable base-pairing nature, is considered to be a highly-selective, yet greatly modifiable device. Its behavior is then described through Boolean Logic, where “true” or “false” outputs are mathematically described as “1” and “0”, respectively. This mathematical approach is then referred to as Logic Gates, where outputs can be predicted based on satisfied environmental conditions. The mechanisms, capable of exhibiting Logic Gate behavior, are described.

Esta dissertação explora os desafios agravados pela miniaturização da tecnologia na fabricação e projeto de circuitos integrados digitais. Os efeitos físicos do regime nanométrico reduzem o rendimento da produção e encurtam a vida útil dos dispositivos, restringindo a utilidade dos padrões de projeto convencionais e ameaçando a evolução da tecnologia CMOS como um todo. Nesta dissertação é exposta uma consistente revisão bibliográfica dos principais efeitos físicos parasitas presentes no regime nanométrico. Como o NBTI tem recebido destaque na literatura relacionada à confiabilidade de circuitos, este efeito de envelhecimento recebe destaque também neste texto, sendo explorado mais detalhadamente. Diversas técnicas de avaliação de redução do NBTI são demonstradas, sendo apresentados, em cada um destes tópicos, trabalhos desenvolvidos no âmbito desta dissertação e seus resultados. O circuito proposto como técnica de avaliação de NBTI permite uso de simulações elétricas para análise de degradação de circuitos. A análise da influência do rearranjo da estrutura de transistores para reduzir a degradação quanto ao NBTI apresenta bons resultados e não impede o uso de outras técnicas combinadas. / This thesis explores the challenges worsened by the technology miniaturization in fabrication and design of digital integrated circuits. The physical effects of nanometric regime reduce the production yield and shorten the devices lifetime, restricting the usefulness of standard design flows and threatening the evolution of CMOS technologies. This thesis exposes a consistent bibliographic review about the main aggressive physical effects of nanometric regime. NBTI has received special attention in reliability literature, so this text follows the same strategy, deeply exploring this aging effect. A broad set of NBTI evaluation and mitigation techniques are explained, including developed works in each one of these categories. The proposed circuit as NBTI evaluation technique allows the use of electrical simulation for circuit degradation analysis. The analysis of the transistors arrangement restructuring as a technique for NBTI degradation reduction shows satisfactory results, while does not restrict the use of other combined techniques.

Supramolecular chemistry is an emerging field of chemistry which has attracted much attention in recent years as a result of its broad applicability in many areas. Thus, the design of functional supramolecular systems is strongly in demand in this field. For this purpose, we have developed ratiometric fluorescent chemosensors for ion sensing and mechanically interlocked structures for their application in molecular logic. In the first part, we report a novel dimeric boradiazaindacene dye which can be converted in one step to an efficient resonance energy transfer (RET) dyad. In addition, if this modification is done with appropriate ligands, RET can be coupled to ion sensing. The utility of this approach is demonstrated in a highly selective, emission ratiometric chemosensor for Ag(I). In the second part, boradiazaindacene dyads designed as energy transfer casettes were modified to signal cation concentrations ratiometrically. If the energy transfer efficiency is increased by changing spectral overlap on cation binding, an enhancement of emission signal ratios can be obtained. A larger range of ratios results in highly improved sensitivity to analyte concentrations. We demonstrate this approach in a de novo design of a novel and highly selective ratiometric chemosensor for Hg(II) ions. In the last part, we synthesized a two-station [2]catenane composed of an &amp / #960 / -electron rich bis-1,5-dihydroxynapthalene[38]-crown-10 (1/5DNPC10) ring interlocked with a second macrocycle containing two &amp / #960 / -electron deficient unit, namely, napthodiimide (NpI) and bipyridinium (BIPY)2+ unit using the Cu(I)-catalyzed Huisgen 1,3-cycloaddition reaction. The resulting bistable [2]catenane is isolated as a single co-conformation which is comprised of the 1/5DNP[38]C10 ring around the NpI unit. Thermal activation of the pure NpI-isomer at 70&amp / #730 / C for 60 h leads to the formation of the BIPY2+-isomer by virtue of the circumrotation of the crown-ether ring along the backbone of the other macrocycle over the steric barrier of the tetra-aryl methane units. The energy barrier for the circumrotation is 28.5&plusmn / 0.3 kcal/mol. Electrochemistry of a 1:1 mixture of the two possible isomers shows that the [2]catenane cannot be switched mechanically on account of the large steric barriers presented by the tetra-aryl methane groups on the electron-accepting ring.