Problem-specific Parameterized Quantum Circuits of the VQE Algorithm for Optimization Problems

The Variational Quantum Eigensolver (VQE) algorithm is attracting much attention to utilize current limited quantum devices. The VQE algorithm requires a quantum circuit with parameters, called a parameterized quantum circuit (PQC), to prepare a quantum state, and the quantum state is used to calculate the expectation value of a given Hamiltonian. Creating sophisticated PQCs is important from the perspective of the convergence speed. Thus, we propose problem-specific PQCs of the VQE algorithm for optimization problems. Our idea is to dynamically create a PQC that reflects the constraints of an optimization problem. With a problem-specific PQC, it is possible to reduce a search space by restricting unitary transformations in favor of the VQE algorithm. As a result, we can speed up the convergence of the VQE algorithm. Experimental results show that the convergence speed of the proposed PQCs is significantly faster than that of the state-of-the-art PQC

A SAT approach to the initial mapping problem in SWAP gate insertion for commuting gates

Most quantum circuits require SWAP gate insertion to run on quantum hardware with limited qubit connectivity. A promising SWAP gate insertion method for blocks of commuting two-qubit gates is a predetermined swap strategy which applies layers of SWAP gates simultaneously executable on the coupling map. A good initial mapping for the swap strategy reduces the number of required swap gates. However, even when a circuit consists of commuting gates, e.g., as in the Quantum Approximate Optimization Algorithm (QAOA) or trotterized simulations of Ising Hamiltonians, finding a good initial mapping is a hard problem. We present a SAT-based approach to find good initial mappings for circuits with commuting gates transpiled to the hardware with swap strategies. Our method achieves a 65% reduction in gate count for random three-regular graphs with 500 nodes. In addition, we present a heuristic approach that combines the SAT formulation with a clustering algorithm to reduce large problems to a manageable size. This approach reduces the number of swap layers by 25% compared to both a trivial and random initial mapping for a random three-regular graph with 1000 nodes. Good initial mappings will therefore enable the study of quantum algorithms, such as QAOA and Ising Hamiltonian simulation applied to sparse problems, on noisy quantum hardware with several hundreds of qubits.Comment: 7 page

Electron Micro­scopic Studies on Retinochoroidal Atrophy in the Human Eye

Nine eyeballs were enucleated from nine patients with excessive myopia, secondary retinochoroidal atrophy, absolute glaucoma, uveal malignant melanoma, Behcet's disease and sympathetic ophthalmia. The retina and choroid were studied with light and electron microscopes. The results were: In excessive myopia, marked blockade of choriocapillaries was accompanied by progressive retinal degeneration. In secondary retinochoroidal atrophy induced by retrobulbar fibrosis, the choriocapillaries were partially blocked and the retina had markedly degenerated. In Behcet's disease, exudative inflammation was recognized in the choroid extending to the retina and causing retinal detachment, though the choriocapillaries remained morphologically normal. In sympathetic ophthalmia, both the choriocapillaries and the retina remained normal, though marked inflammation was recognized in the outer layer of the choroid. In absolute glaucoma, the fine structures of the choriocapillary were well preserved in spite of bulbar hypertonia. In uveal malignant melanoma, the ultra structure of the choriocapillary near the tumor was well preserved. The choriocapillaries were normal even when the retina had degenerated. Retinal degeneration was recognized when changes such as blockage, disappearance, dilatation and increased permeability were found in the choriocapillaries. Damage to the choriocapillaries might play an important role in inducing and developing retinochoroidal atrophy.</p

Phylogenetic footprint of the plant clock system in angiosperms: evolutionary processes of Pseudo-Response Regulators

<p>Abstract</p> <p>Background</p> <p>Plant circadian clocks regulate many photoperiodic and diurnal responses that are conserved among plant species. The plant circadian clock system has been uncovered in the model plant, <it>Arabidopsis thaliana</it>, using genetics and systems biology approaches. However, it is still not clear how the clock system had been organized in the evolutionary history of plants. We recently revealed the molecular phylogeny of <it>LHY/CCA1 </it>genes, one of the essential components of the clock system. The aims of this study are to reconstruct the phylogenetic relationships of angiosperm clock-associated <it>PRR </it>genes, the partner of the <it>LHY/CCA1 </it>genes, and to clarify the evolutionary history of the plant clock system in angiosperm lineages.</p> <p>Results</p> <p>In the present study, to investigate the molecular phylogeny of <it>PRR </it>genes, we performed two approaches: reconstruction of phylogenetic trees and examination of syntenic relationships. Phylogenetic analyses revealed that <it>PRR </it>genes had diverged into three clades prior to the speciation of monocots and eudicots. Furthermore, copy numbers of <it>PRR </it>genes have been independently increased in monocots and eudicots as a result of ancient chromosomal duplication events.</p> <p>Conclusions</p> <p>Based on the molecular phylogenies of both <it>PRR </it>genes and <it>LHY/CCA1 </it>genes, we inferred the evolutionary process of the plant clock system in angiosperms. This scenario provides evolutionary information that a common ancestor of monocots and eudicots had retained the basic components required for reconstructing a clock system and that the plant circadian clock may have become a more elaborate mechanism after the speciation of monocots and eudicots because of the gene expansion that resulted from polyploidy events.</p

Fluctuation properties of strength function associated with the giant quadrupole resonance in 208Pb

We performed fluctuation analysis by means of the local scaling dimension for the strength function of the isoscalar (IS) giant quadrupole resonance (GQR) in 208Pb where the strength function is obtained by the shell model calculation including 1p1h and 2p2h configurations. It is found that at almost all energy scales, fluctuation of the strength function obeys the Gaussian orthogonal ensemble (GOE) random matrix theory limit. This is contrasted with the results for the GQR in 40Ca, where at the intermediate energy scale about 1.7 MeV a deviation from the GOE limit was detected. It is found that the physical origin for this different behavior of the local scaling dimension is ascribed to the difference in the properties of the damping process.Comment: 10 pages, 14 figures, submitted to Physical Review

Bilateral Optic Disc Anomalies Associated with PAX2 Mutation in a Case of Potter Sequence

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Cost-effectiveness Analysis of CO2 Reduction in the Automobile Sector

Various problems relating to energy and the environment clearly exist, such as global warming and a steep rise in the price fossil fuels, and resources. These problems should be addressed in the medium term or long run. As for the abatement of greenhouse gas emission, active discussions have been held on the stage of world politics to achieve the long-term goal. Although various approaches have been proposed by several research institutions and countries, sufficient studies have not yet been conducted on the roles of individual countries and sectors. Specifically, in the automotive transportation sector wherein oil demand and CO2 emissions are estimated to rise in the future with the marked progress of motorization in developing countries, it is increasingly important to study these subjects. We focused on the automotive transportation sector and studied the CO2 abatement potential and its cost performance in this sector. This article reports the results of the study.energy and the environment, Climate change, automotive transportation

Hairball-Like Migration of “Onyx Threads” into the Draining Vein during Transarterial Embolization of a Dural Arteriovenous Fistula: A Case Report and Experimental Validation

Transarterial embolization using Onyx is a well-established treatment for dural arteriovenous fistulas (DAVFs). However, complications can arise when Onyx migrates into the venous side, impairing the draining veins. We encountered a case where Onyx, injected through the arterial side, strayed into the jugular vein, forming a hairball-like structure. Our study aimed to investigate the underlying mechanism of this unusual phenomenon. We postulated that Onyx precipitates into thread-like shapes when passing through extremely narrow openings. To test this, we extruded Onyx from a syringe through a 27-gauge needle into a silicone tube with flowing water. By varying the flow speed, we observed the hardening behavior of Onyx. Under slow flow, the extruded Onyx quickly solidified at the needle tip, forming a round mass. Conversely, high-speed flow resulted in Onyx being dispersed as small pieces. We successfully replicated the formation of “Onyx threads” under continuous slow flow conditions, similar to our case. This phenomenon occurs when Onyx unexpectedly migrates to the draining vein through a tiny opening during transarterial embolization for arteriovenous shunt diseases. Early recognition and appropriate measures are necessary to prevent occlusive complications in the draining veins and the pulmonary system

A Novel Training Method for Endovascular Clot Retrieval Using a Portable Vascular Model and Red Film

Hands-on training is a crucial part of education in neuroendovascular treatment to ensure safe and rapid acquisition of techniques. However, there is a significant gap between training and actual clinical practice. This study will introduce innovations for more practical thrombus retrieval training that was developed in this process. A Smart Vascular Model 3 in 1 was used. A pink pseudothrombus was inserted into the M1 (horizontal segment of the middle cerebral artery) section of the model. Then, a “red underlay” purchased at a stationery store was placed to cover the proximal part of M1 and beyond so that the pseudothrombus was not visible. The thrombus was retrieved during training by looking for the location of the thrombus based on the behavior and resistance of the tip of the guidewire and deployment of the stent retriever. The participants were required to have detailed observation skills and precise manipulation skills using a red film to prevent the direct visualization of the pseudothrombus. The implementation of this innovation to the previous hands-on training made the training more practical and effective. If the exact thrombus location can be determined by the behavior of the wire tip, the device’s capabilities can be maximized, and rapid retrieval can be expected. It could also reduce complications, as unnecessary peripheral guidance of the device could be avoided