233 research outputs found

    Sequential minimal optimization for quantum-classical hybrid algorithms

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    We propose a sequential minimal optimization method for quantum-classical hybrid algorithms, which converges faster, is robust against statistical error, and is hyperparameter-free. Specifically, the optimization problem of the parameterized quantum circuits is divided into solvable subproblems by considering only a subset of the parameters. In fact, if we choose a single parameter, the cost function becomes a simple sine curve with period 2Ï€2\pi, and hence we can exactly minimize with respect to the chosen parameter. Furthermore, even in general cases, the cost function is given by a simple sum of trigonometric functions with certain periods and hence can be minimized by using a classical computer. By repeatedly performing this procedure, we can optimize the parameterized quantum circuits so that the cost function becomes as small as possible. We perform numerical simulations and compare the proposed method with existing gradient-free and gradient-based optimization algorithms. We find that the proposed method substantially outperforms the existing optimization algorithms and converges to a solution almost independent of the initial choice of the parameters. This accelerates almost all quantum-classical hybrid algorithms readily and would be a key tool for harnessing near-term quantum devices.Comment: 11 pages, 4 figure

    Subspace Variational Quantum Simulator

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    Quantum simulation is one of the key applications of quantum computing, which can accelerate research and development in chemistry, material science, etc. Here, we propose an efficient method to simulate the time evolution driven by a static Hamiltonian, named subspace variational quantum simulator (SVQS). SVQS employs the subspace-search variational eigensolver (SSVQE) to find a low-energy subspace and further extends it to simulate dynamics within the low-energy subspace. More precisely, using a parameterized quantum circuit, the low-energy subspace of interest is encoded into a computational subspace spanned by a set of computational basis, where information processing can be easily done. After the information processing, the computational subspace is decoded to the original low-energy subspace. This allows us to simulate the dynamics of low-energy subspace with lower overhead compared to existing schemes. While the dimension is restricted for feasibility on near-term quantum devices, the idea is similar to quantum phase estimation and its applications such as quantum linear system solver and quantum metropolis sampling. Because of this simplicity, we can successfully demonstrate the proposed method on the actual quantum device using Regetti Quantum Cloud Service. Furthermore, we propose a variational initial state preparation for SVQS, where the initial states are searched from the simulatable eigensubspace. Finally, we demonstrate SVQS on Rigetti Quantum Cloud Service

    A new technique for venous unifocalization of the bilateral superior vena cava with the Glenn procedure

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    Gait analysis of locusts walking on level, vertical, and ceiling planes

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    The 11th International Symposium on Adaptive Motion of Animals and Machines. Kobe University, Japan. 2023-06-06/09. Adaptive Motion of Animals and Machines Organizing Committee.Poster Session P5

    Evaluating on-demand video lectures

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    The popularity of online classes in university education has grown rapidly since the COVID-19 outbreak. This study aims to examine the association between the detailed characteristics / various contexts of students and the evaluation of online classes. An online questionnaire survey administered to third- and fourth-grade medical students of Tokushima University in September 2021—with 101 (42.8%) valid responses—showed the respondents’ general impressions, comprehension, convenience, and desire for online classes even after the pandemic ends were significantly higher for the on-demand lectures than for simultaneous online classes. Notably, students who did not do other things while watching video lectures (10.9%) rated on-demand lectures as facilitating significantly higher impression, comprehension, and convenience than those who did other things (89.1%). A multivariate analysis revealed that students who did not do anything else while watching, whose waking time changed slightly, who commuted to school for shorter periods, who were not good at morning lectures, and who watched at high speed rated the video lectures highly. Thus, video lectures are appreciated by students who are committed to learning, which is a positive result for the future of on-demand education

    Study of Views on Posthumous Reproduction, Focusing on Its Relation with Views on Family and Religion in Modern Japan

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    Posthumous reproduction has been performed in Japan several times, without sufficient civic discussion on its appropriateness or legislative regulation. There have even been several lawsuits on posthumous acknowledgment (in which a baby born to a deceased father has the same birthright as a baby born to a living father), and some judgments have proposed the need to develop societal agreement on posthumous reproduction and suggested legislative settlement. With this background, this study aims to clarify the views of the Japanese people regarding posthumous reproduction. In December 2007, we distributed a questionnaire on posthumous reproduction in relation to beliefs about family and religion to 32 universities across the country, and received 3,719 replies. It was found that about 60&#65397; of respondents agreed with posthumous reproduction. Statistical analysis was applied to the relationship between this overall position on posthumous reproduction and views on assisted reproduction technologies, family, religion, and so on. The degree of support for posthumous reproduction was strongly correlated with the degree of affirmation of assisted reproduction technologies and a liberal worldview with emphasis on self-determination. On the other hand, there was also a strong correlation with having a traditional view of family, such as family succession. The degree of support for posthumous reproduction was also highly correlated with the intimacy among family members, underlying which was a strong connection to the traditional religious belief in Japan that deceased family members watch the living ones. The view on posthumous reproduction is culturally complex and cannot be explained by a simple dichotomy between traditional conservatives and liberals.</p

    CRP in PMR and RS3PE syndrome

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    Polymyalgia rheumatica (PMR) and remitting seronegative symmetrical synovitis with pitting edema (RS3PE) syndrome are common inflammatory rheumatic diseases in the elderly. In this study, we investigate predictive factors which correspond to subsequent disease control of PMR and RS3PE syndrome. Twenty four patients, which contained 18 PMR and 6 RS3PE syndrome, were treated with initial dosages of 10-20 mg per day oral prednisolone, and the dosage of prednisolone was then tapered. Significantly higher initial CRP was observed in patients with poor disease control than in those with good disease control afterwards. The number of patients with negative CRP after 4 weeks was significantly more in patients with good disease control after 1 year than in those with poor disease control. Patients were shown to be in good disease control status after 1 year when CRP after 4 weeks became negative even if they had initial high CRP. Our study clarify that to make CRP negative after 4 weeks is associated with subsequent suppression of the disease activity and with decreased dosages of corticosteroids

    Passive immunisation of goldfish with the serum of those surviving a Cyprinid herpesvirus 2 infection after high temperature water treatment

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    Herpesviral haematopoietic necrosis of goldfish caused by cyprinid herpesvirus 2 (CyHV-2) can be controlled by raising water temperature to a virus non-permissive temperature of 34℃. Consequently, the goldfish can survive and acquire resistance to the disease; the underlying mechanism of acquired resistance, however, remains unclear. In this study, we investigated serological changes in the surviving goldfish, with a focus on their humoral immunity, and examined whether sera of the surviving goldfish conferred passive immunity to naive goldfish. Levels of the anti-CyHV-2 antibodies in 8 of the 9 survivors measured via ELISA were higher than those in control fish. Neutralising antibodies were detected in the sera of 2 survivors, but no direct correlation was observed between ELISA optical density value and neutralising antibody titer. Passive immunisation tests showed that recipients injected with the serum containing neutralising antibodies showed higher survival rates than the control group. The sera from 6 other survivors showed no effect on the recipient\u27s mortality regardless of anti-CyHV-2 antibody levels. These results suggest that neutralising antibodies can contribute to acquired immunity in survivors, and other protective factors, including cell-mediated immunity, may work in the survivors that show no detectable neutralising antibodies
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