7 research outputs found
Stability of quantum states of finite macroscopic systems
We study the stabilities of quantum states of macroscopic systems, against
noises, against perturbations from environments, and against local
measurements. We show that the stabilities are closely related to the cluster
property, which describes the strength of spatial correlations of fluctuations
of local observables, and to fluctuations of additive operators. The present
theory has many applications, among which we discuss the mechanism of phase
transitions in finite systems and quantum computers with a huge number of
qubits.Comment: Proceedings of the Japan-Italy Joint Waseda Workshop on "Fundamental
Problems in Quantum Mechanics", 27-29 September, 2001, Tokyo, Japan. (Edited
by S. Tasaki, to be published from World Scientific, 2002) 7 pages, no
figure
Appearance and Stability of Anomalously Fluctuating States in Shor's Factoring Algorithm
We analyze quantum computers which perform Shor's factoring algorithm, paying
attention to asymptotic properties as the number L of qubits is increased.
Using numerical simulations and a general theory of the stabilities of
many-body quantum states, we show the following: Anomalously fluctuating states
(AFSs), which have anomalously large fluctuations of additive operators, appear
in various stages of the computation. For large L, they decohere at anomalously
great rates by weak noises that simulate noises in real systems. Decoherence of
some of the AFSs is fatal to the results of the computation, whereas
decoherence of some of the other AFSs does not have strong influence on the
results of the computation. When such a crucial AFS decoheres, the probability
of getting the correct computational result is reduced approximately
proportional to L^2. The reduction thus becomes anomalously large with
increasing L, even when the coupling constant to the noise is rather small.
Therefore, quantum computations should be improved in such a way that all AFSs
appearing in the algorithms do not decohere at such great rates in the existing
noises.Comment: 11 figures. A few discussions were added in verion 2. Version 3 is
the SAME as version 2; only errors during the Web-upload were fixed. Version
4 is the publised version, in which several typos are fixed and the reference
list is update
Ethnic comparison in takotsubo syndrome : novel insights from the International Takotsubo Registry
© The Author(s) 2021. Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.Background: Ethnic disparities have been reported in cardiovascular disease. However, ethnic disparities in takotsubo syndrome (TTS) remain elusive. This study assessed differences in clinical characteristics between Japanese and European TTS patients and determined the impact of ethnicity on in-hospital outcomes.
Methods: TTS patients in Japan were enrolled from 10 hospitals and TTS patients in Europe were enrolled from 32 hospitals participating in the International Takotsubo Registry. Clinical characteristics and in-hospital outcomes were compared between Japanese and European patients.
Results: A total of 503 Japanese and 1670 European patients were included. Japanese patients were older (72.6 ± 11.4 years vs. 68.0 ± 12.0 years; p < 0.001) and more likely to be male (18.5 vs. 8.4%; p < 0.001) than European TTS patients. Physical triggering factors were more common (45.5 vs. 32.0%; p < 0.001), and emotional triggers less common (17.5 vs. 31.5%; p < 0.001), in Japanese patients than in European patients. Japanese patients were more likely to experience cardiogenic shock during the acute phase (15.5 vs. 9.0%; p < 0.001) and had a higher in-hospital mortality (8.2 vs. 3.2%; p < 0.001). However, ethnicity itself did not appear to have an impact on in-hospital mortality. Machine learning approach revealed that the presence of physical stressors was the most important prognostic factor in both Japanese and European TTS patients.
Conclusion: Differences in clinical characteristics and in-hospital outcomes between Japanese and European TTS patients exist. Ethnicity does not impact the outcome in TTS patients. The worse in-hospital outcome in Japanese patients, is mainly driven by the higher prevalence of physical triggers.Open Access funding provided by Universität Zürich. CT has been supported by the H.H. Sheikh Khalifa bin Hamad Al-Thani Research Programme and the Swiss Heart Foundation. L.S.M. has been supported by EU HORIZON 2020 (SILICOFCM ID777204). J.R.G has received a grant “Filling the gap” from the University of Zurich. The InterTAK Registry is supported by The Biss Davies Charitable Trust.info:eu-repo/semantics/publishedVersio
Ethnic comparison in takotsubo syndrome: novel insights from the International Takotsubo Registry
Background Ethnic disparities have been reported in cardiovascular disease. However, ethnic disparities in takotsubo syndrome (TTS) remain elusive. This study assessed differences in clinical characteristics between Japanese and European TTS patients and determined the impact of ethnicity on in-hospital outcomes.Methods TTS patients in Japan were enrolled from 10 hospitals and TTS patients in Europe were enrolled from 32 hospitals participating in the International Takotsubo Registry. Clinical characteristics and in-hospital outcomes were compared between Japanese and European patients.Results A total of 503 Japanese and 1670 European patients were included. Japanese patients were older (72.6 +/- 11.4 years vs. 68.0 +/- 12.0 years; p Conclusion Differences in clinical characteristics and in-hospital outcomes between Japanese and European TTS patients exist. Ethnicity does not impact the outcome in TTS patients. The worse in-hospital outcome in Japanese patients, is mainly driven by the higher prevalence of physical triggers.</p