BACKGROUND The validity of quantitative coronary angiography (QCA) after stent placement has been questioned because the optical density of a metallic stent, added to the density of a contrast-filled lumen, could affect border definition. METHODS AND RESULTS We deployed 3.0- and 4.0-mm Palmaz-Schatz, Wiktor, Multilink, NIR, and InStent stents in precision-cast phantoms. Central lumens of 2.0 ...

Quantum cellular automata (QCA) consist in an array of identical finite-dimensional quantum systems. The whole array evolves in discrete time steps by iterating a unitary operator G. Moreover this global evolution G is shift-invariant (acts everywhere the same), and local (information can only be transmitted at a bounded speed). Whilst this axiomatic definition is clearly the natural ‘quantizat...

QCA has recently been subject to massive criticism and although the substance of that criticism is not completely new, it differs from earlier critiques by invoking simulations for the evaluation of QCA. In addition to debates about the meaning of the simulation results, there is a more fundamental discussion about whether simulations promise any relevant insights in principle. Some voices in t...

BACKGROUND Studies conducted decades ago described substantial disagreement and errors in physicians' angiographic interpretation of coronary stenosis severity. Despite the potential implications of such findings, no large-scale efforts to measure or improve clinical interpretation were subsequently undertaken. METHODS AND RESULTS We compared clinical interpretation of stenosis severity in co...

Quantum-Dot Cellular Automata (QCA) is a computational scheme utilizing the position of interacting single electrons within arrays of quantum dots ("cells") to encode and process binary information. Clocked QCA architectures can provide power gain, logic level restoration, and memory features. Using arrays of micron-sized metal dots, we experimentally demonstrate operation of a QCA latch-invert...

Quantum-dot Cellular Automata (QCA) are an emerging computation technology in which basic states are represented by nanosize particles and logic operations are conducted through corresponding effects such as Coulomb interaction. This allows to overcome physical boundaries of conventional solutions such as CMOS and, hence, constitutes a promising direction for future computing devices. Despite t...

In this paper, we propose a novel Quantum-dot Cellular Automata (QCA) based Programmable Switch Matrix which can be used as a routing element for future nano Field Programmable Gate Arrays (FPGAs). QCA technology is an emerging technology based on encoding binary information in charge configuration within quantum dot cells. In FPGAs, the Programmable Switch Matrix (PSM) is the interconnection c...

The authors present qualitative comparative analysis (QCA) as a viable method for strategic management research. Specifically, they demonstrate its ability to examine the potential interdependence and complexity among effects through a study of how industry, corporate, and business-unit attributes combine in determining business-unit performance. They present in an accessible manner the consecu...

In this paper, a novel quantum-dot cellular automata (QCA) adder design is presented that reduces the number of QCA cells compared to previously reported designs. The proposed one-bit QCA adder structure is based on a new algorithm that requires only three majority gates and two inverters for the QCA addition. By connecting n one-bit QCA adders, we can obtain an n-bit carry look-ahead adder wit...

Quantum dot Cellular Automata (QCA) is a novel and potentially attractive technology for implementing computing architectures at the nano-scale. The basic Boolean primitive in QCA is the majority gate. In this paper we present a novel design for QCA cells and another possible and unconventional scheme for majority gates. By applying these items, the hardware requirements for a QCA design can be...