305 results on '"Ji SE"'
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2. Faithful measure of Quantum non-Gaussianity via quantum relative entropy
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Park, Jiyong, Lee, Jaehak, Baek, Kyunghyun, Ji, Se-Wan, and Nha, Hyunchul
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Quantum Physics - Abstract
We introduce a measure of quantum non-Gaussianity (QNG) for those quantum states not accessible by a mixture of Gaussian states in terms of quantum relative entropy. Specifically, we employ a convex-roof extension using all possible mixed-state decompositions beyond the usual pure-state decompositions. We prove that this approach brings a QNG measure fulfilling the properties desired as a proper monotone under Gaussian channels and conditional Gaussian operations. As an illustration, we explicitly calculate QNG for the noisy single-photon states and demonstrate that QNG coincides with non-Gaussianity of the state itself when the single-photon fraction is sufficiently large., Comment: 6 pages, 1 figure, published version
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- 2018
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3. Quantifying non-Gaussianity of quantum-state correlation
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Park, Jiyong, Lee, Jaehak, Ji, Se-Wan, and Nha, Hyunchul
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Quantum Physics - Abstract
We consider how to quantify non-Gaussianity for the correlation of a bipartite quantum state by using various measures such as relative entropy and geometric distances. We first show that an intuitive approach, i.e., subtracting the correlation of a reference Gaussian state from that of a target non-Gaussian state, fails to yield a non-negative measure with monotonicity under local Gaussian channels. Our finding clearly manifests that quantum-state correlations generally have no Gaussian extremality. We therefore propose a different approach by introducing relevantly averaged states to address correlation. This enables us to define a non-Gaussianity measure based on, e.g., the trace-distance and the fidelity, fulfilling all requirements as a measure of non-Gaussian correlation. For the case of the fidelity-based measure, we also present readily computable lower bounds of non-Gaussian correlation., Comment: published version, 10 pages, 6 figures
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- 2017
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4. Monogamy relation in multipartite continuous-variable quantum teleportation
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Lee, Jaehak, Ji, Se-Wan, Park, Jiyong, and Nha, Hyunchul
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Quantum Physics - Abstract
Quantum teleportation (QT) is a fundamentally remarkable communication protocol that also finds many important applications for quantum informatics. Given a quantum entangled resource, it is crucial to know to what extent one can accomplish the QT. This is usually assessed in terms of output fidelity, which can also be regarded as an operational measure of entanglement. In the case of multipartite communication when each communicator possesses a part of $N$-partite entangled state, not all pairs of communicators can achieve a high fidelity due to monogamy property of quantum entanglement. We here investigate how such a monogamy relation arises in multipartite continuous-variable (CV) teleportation particularly using a Gaussian entangled state. We show a strict monogamy relation, i.e. a sender cannot achieve a fidelity higher than optimal cloning limit with more than one receiver. While this seems rather natural owing to the no-cloning theorem, a strict monogamy relation still holds even if the sender is allowed to individually manipulate the reduced state in collaboration with each receiver to improve fidelity. The local operations are further extended to non-Gaussian operations such as photon subtraction and addition, and we demonstrate that the Gaussian cloning bound cannot be beaten by more than one pair of communicators. Furthermore we investigate a quantitative form of monogamy relation in terms of teleportation capability, for which we show that a faithful monogamy inequality does not exist., Comment: 10 pages, 6 figures, published version
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- 2016
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5. Gaussian benchmark for optical communication aiming towards ultimate capacity
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Lee, Jaehak, Ji, Se-Wan, Park, Jiyong, and Nha, Hyunchul
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Quantum Physics - Abstract
We establish the fundamental limit of communication capacity within Gaussian schemes under phase-insensitive Gaussian channels, which employ multimode Gaussian states for encoding and collective Gaussian operations and measurements for decoding. We prove that this Gaussian capacity is additive, i.e., its upper bound occurs with separable encoding and separable receivers so that a single-mode communication suffices to achieve the largest capacity under Gaussian schemes. This rigorously characterizes the gap between the ultimate Holevo capacity and the capacity within Gaussian communication, showing that Gaussian regime is not sufficient to achieve the Holevo bound particularly in the low-photon regime. Furthermore the Gaussian benchmark established here can be used to critically assess the performance of non-Gaussian protocols for optical communication. We move on to identify non-Gaussian schemes to beat the Gaussian capacity and show that a non-Gaussian receiver recently implemented by Becerra et al. [Nat. Photon. 7, 147 (2013)] can achieve this aim with an appropriately chosen encoding strategy., Comment: 9 pages, 6 figures, with supplemental material
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- 2016
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6. Quantum steering of Gaussian states via non-Gaussian measurements
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Ji, Se-Wan, Lee, Jaehak, Park, Jiyong, and Nha, Hyunchul
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Quantum Physics - Abstract
Quantum steering---a strong correlation to be verified even when one party or its measuring device is fully untrusted---not only provides a profound insight into quantum physics but also offers a crucial basis for practical applications. For continuous-variable (CV) systems, Gaussian states among others have been extensively studied, however, mostly confined to Gaussian measurements. While the fulfillment of Gaussian criterion is sufficient to detect CV steering, whether it is also necessary for Gaussian states is a question of fundamental importance in many contexts. This critically questions the validity of characterizations established only under Gaussian measurements like the quantification of steering and the monogamy relations. Here, we introduce a formalism based on local uncertainty relations of non-Gaussian measurements, which is shown to manifest quantum steering of some Gaussian states that Gaussian criterion fails to detect. To this aim, we look into Gaussian states of practical relevance, i.e. two-mode squeezed states under a lossy and an amplifying Gaussian channel. Our finding significantly modifies the characteristics of Gaussian-state steering so far established such as monogamy relations and one-way steering under Gaussian measurements, thus opening a new direction for critical studies beyond Gaussian regime., Comment: Published version, 9 pages, 3 figures
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- 2015
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7. Steering Criteria via Covariance Matrices of Local Observables in Arbitrary Dimensional Quantum Systems
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Ji, Se-Wan, Lee, Jaehak, Park, Jiyong, and Nha, Hyunchul
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Quantum Physics - Abstract
We derive steerability criteria applicable for both finite and infinite dimensional quantum systems using covariance matrices of local observables. We show that these criteria are useful to detect a wide range of entangled states particularly in high dimensional systems and that the Gaussian steering criteria for general M x N-modes of continuous variables are obtained as a special case. Extending from the approach of entanglement detection via covariance matrices, our criteria are based on the local uncertainty principles incorporating the asymmetric nature of steering scenario. Specifically, we apply the formulation to the case of local orthogonal observables and obtain some useful criteria that can be straightforwardly computable, and testable in experiment, with no need for numerical optimization., Comment: 6 pages with further "Remarks" and "Acknowledgement" added
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- 2015
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8. Testing nonclassicality and non-Gaussianity in phase space
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Park, Jiyong, Zhang, Junhua, Lee, Jaehak, Ji, Se-Wan, Um, Mark, Lv, Dingshun, Kim, Kihwan, and Nha, Hyunchul
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Quantum Physics - Abstract
We theoretically propose and experimentally demonstrate a nonclassicality test of single-mode field in phase space, which has an analogy with the nonlocality test proposed by Banaszek and Wodkiewicz [Phys. Rev. Lett. 82, 2009 (1999)]. Our approach to deriving the classical bound draws on the fact that the Wigner function of a coherent state is a product of two independent distributions as if the orthogonal quadratures (position and momentum) in phase space behave as local realistic variables. Our method detects every pure nonclassical Gaussian state, which can also be extended to mixed states. Furthermore, it sets a bound for all Gaussian states and their mixtures, thereby providing a criterion to detect a genuine quantum non-Gaussian state. Remarkably, our phase-space approach with invariance under Gaussian unitary operations leads to an optimized test for a given non-Gaussian state. We experimentally show how this enhanced method can manifest quantum non-Gaussianity of a state by simply choosing phase-space points appropriately, which is essentially equivalent to implementing a squeezing operation on a given state., Comment: 5 pages and 3 figures with Supplemental Material, published version
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- 2015
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9. Classical capacity of Gaussian communication under a single noisy channel
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Lee, Jaehak, Ji, Se-Wan, Park, Jiyong, and Nha, Hyunchul
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Quantum Physics - Abstract
A long-standing problem on the classical capacity of bosonic Gaussian channels has recently been resolved by proving the minimum output entropy conjecture. It is also known that the ultimate capacity quantified by the Holevo bound can be achieved asymptotically by using an infinite number of channels. However, it is less understood to what extent the communication capacity can be reached if one uses a finite number of channels, which is a topic of practical importance. In this paper, we study the capacity of Gaussian communication, i.e., employing Gaussian states and Gaussian measurements to encode and decode information under a single-channel use. We prove that the optimal capacity of single-channel Gaussian communication is achieved by one of two well-known protocols, i.e., coherent-state communication or squeezed-state communication, depending on the energy (number of photons) as well as the characteristics of the channel. Our result suggests that the coherent-state scheme known to achieve the ultimate information-theoretic capacity is not a practically optimal scheme for the case of using a finite number of channels. We find that overall the squeezed-state communication is optimal in a small-photon-number regime whereas the coherent-state communication performs better in a large-photon-number regime., Comment: 9 pages, 4 figures, published version
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- 2015
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10. Quantum steering of multimode Gaussian states by Gaussian measurements: monogamy relations and the Peres conjecture
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Ji, Se-Wan, Kim, M. S., and Nha, Hyunchul
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Quantum Physics - Abstract
It is a topic of fundamental and practical importance how a quantum correlated state can be reliably distributed through a noisy channel for quantum information processing. The concept of quantum steering recently defined in a rigorous manner is relevant to study it under certain circumstances and we here address quantum steerability of Gaussian states to this aim. In particular, we attempt to reformulate the criterion for Gaussian steering in terms of local and global purities and show that it is sufficient and necessary for the case of steering a 1-mode system by a $N$-mode system. It subsequently enables us to reinforce a strong monogamy relation under which only one party can steer a local system of 1-mode. Moreover, we show that only a negative partial-transpose state can manifest quantum steerability by Gaussian measurements in relation to the Peres conjecture. We also discuss our formulation for the case of distributing a two-mode squeezed state via one-way quantum channels making dissipation and amplification effects, respectively. Finally, we extend our approach to include non-Gaussian measurements, more precisely, all orders of higher-order squeezing measurements, and find that this broad set of non-Gaussian measurements is not useful to demonstrate steering for Gaussian states beyond Gaussian measurements., Comment: published version, 9 pages
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- 2014
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11. Continuous-variable dense coding via a general Gaussian state: Monogamy relation
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Lee, Jaehak, Ji, Se-Wan, Park, Jiyong, and Nha, Hyunchul
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Quantum Physics - Abstract
We study a continuous variable (CV) dense-coding protocol, originally proposed to employ a two-mode squeezed state, using a general two-mode Gaussian state as a quantum channel. We particularly obtain conditions to manifest quantum advantage by beating two well-known single-mode schemes, namely, the squeezed-state scheme (best Gaussian scheme) and the number-state scheme (optimal scheme achieving the Holevo bound). We then extend our study to a multipartite Gaussian state and investigate the monogamy of operational entanglement measured by the communication capacity under the dense-coding protocol. We show that this operational entanglement represents a strict monogamy relation, by means of Heisenberg's uncertainty principle among different parties, i.e., the quantum advantage for communication can be possible for only one pair of two-mode systems among many parties.
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- 2014
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12. Gaussian states under coarse-grained continuous variable measurements
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Park, Jiyong, Ji, Se-Wan, Lee, Jaehak, and Nha, Hyunchul
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Quantum Physics - Abstract
The quantum-to-classical transition of a quantum state is a topic of great interest in fundamental and practical aspects. A coarse-graining in quantum measurement has recently been suggested as its possible account in addition to the usual decoherence model. We here investigate the reconstruction of a Gaussian state (single mode and two modes) by coarse-grained homodyne measurements. To this aim, we employ two methods, the direct reconstruction of the covariance matrix and the maximum likelihood estimation (MLE), respectively, and examine the reconstructed state under each scheme compared to the state interacting with a Gaussian (squeezed thermal) reservoir. We clearly demonstrate that the coarse-graining model, though applied equally to all quadrature amplitudes, is not compatible with the decoherence model by a thermal (phase-insensitive) reservoir. Furthermore, we compare the performance of the direct reconstruction and the MLE methods by investigating the fidelity and the nonclassicality of the reconstructed states and show that the MLE method can generally yield a more reliable reconstruction, particularly without information on a reference frame (phase of input state)., Comment: published version, 9 pages, 5 figures
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- 2014
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13. Increasing and decreasing entanglement characteristics for continuous variables by a local photon subtraction
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Lee, Su-Yong, Ji, Se-Wan, and Lee, Chang-Woo
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Quantum Physics - Abstract
We investigate how the entanglement characteristics of a non-Gaussian entangled state are increased or decreased by a local photon subtraction operation. The non-Gaussian entangled state is generated by injecting a single-mode non-Gaussian state and a vacuum state into a 50:50 beam splitter. We consider a photon-added coherent state and an odd coherent state as a single-mode non-Gaussian state. In the regime of small amplitude, we show that the performance of quantum teleportation and the second-order Einstein-Podolsky- Rosen-type correlation can both be enhanced, whereas the degree of entanglement decreases, for the output state when a local photon subtraction operation is applied to the non-Gaussian entangled state. The counterintuitive effect is more prominent in the limit of nearly zero amplitude., Comment: Published version, 7 pages, 3 figures
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- 2013
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14. Quantum linear amplifier enhanced by photon subtraction and addition
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Kim, Ho-Joon, Lee, Su-Yong, Ji, Se-Wan, and Nha, Hyunchul
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Quantum Physics - Abstract
A deterministic quantum amplifier inevitably adds noise to an amplified signal due to the uncertainty principle in quantum physics. We here investigate how a quantum-noise-limited amplifier can be improved by additionally employing the photon subtraction, the photon addition, and a coherent superposition of the two, thereby making a probabilistic, heralded, quantum amplifier. We show that these operations can enhance the performance in amplifying a coherent state in terms of intensity gain, fidelity, and phase uncertainty. In particular, the photon subtraction turns out to be optimal for the fidelity and the phase concentration among these elementary operations, while the photon addition also provides a significant reduction in the phase uncertainty with the largest gain effect., Comment: published version, 7 pages, 9 figures
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- 2012
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15. Efficient entanglement criteria beyond Gaussian limits using Gaussian measurements
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Nha, Hyunchul, Lee, Su-Yong, Ji, Se-Wan, and Kim, M. S.
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Quantum Physics - Abstract
We present a formalism to derive entanglement criteria beyond the Gaussian regime that can be readily tested by only homodyne detection. The measured observable is the Einstein-Podolsky-Rosen (EPR) correlation. Its arbitrary functional form enables us to detect non-Gaussian entanglement even when an entanglement test based on second-order moments fails. We illustrate the power of our experimentally friendly criteria for a broad class of non-Gaussian states under realistic conditions. We also show rigorously that quantum teleportation for continuous variables employs a specific functional form of EPR correlation., Comment: published version, 6 pages, 3 figures, including Supplemental Material
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- 2012
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16. Enhancing quantum entanglement for continuous variables by a coherent superposition of photon subtraction and addition
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Lee, Su-Yong, Ji, Se-Wan, Kim, Ho-Joon, and Nha, Hyunchul
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Quantum Physics - Abstract
We investigate how the entanglement properties of a two-mode state can be improved by performing a coherent superposition operation of photon subtraction and addition, proposed by Lee and Nha [Phys. Rev. A 82, 053812 (2010)], on each mode. We show that the degree of entanglement, the EPR-type correlation, and the performance of quantum teleportation can be all enhanced for the output state when the coherent operation is applied to a two-mode squeezed state. The effects of the coherent operation are more prominent than those of the mere photon subtraction and the addition particularly in the small squeezing regime, whereas the optimal operation becomes the photon subtraction in the large-squeezing regime., Comment: 6 pages, 6 figures, published version
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- 2011
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17. Coherent-state optical qudit cluster state generation and teleportation via homodyne detection
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Kim, Jaewan, Lee, Juhui, Ji, Se-Wan, Nha, Hyunchul, Anisimov, Petr M., and Dowling, Jonathan P.
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Quantum Physics ,Physics - Optics - Abstract
Defining a computational basis of pseudo-number states, we interpret a coherent state of large amplitude, $|\alpha|\gg\frac{d}{2\pi}$, as a qudit --- a $d$-level quantum system --- in a state that is an even superposition of $d$ pseudo-number states. A pair of such coherent-state qudits can be prepared in maximally entangled state by generalized Controlled-$Z$ operation that is based on cross-Kerr nonlinearity, which can be weak for large $d$. Hence, a coherent-state optical qudit cluster state can be prepared by repetitive application of the generalized Controlled-$Z$ operation to a set of coherent states. We thus propose an optical qudit teleportation as a simple demonstration of cluster state quantum computation., Comment: 5 figures
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- 2010
18. Reply to the comment on 'Loophole-free Bell test for continuous variables via wave and particle correlations'
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Ji, Se-Wan, Kim, Jaewan, Lee, Hai-Woong, Zubairy, M. S., and Nha, Hyunchul
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Quantum Physics - Abstract
In a recent note, Cavalcanti and Scarani (CS) constructed a counter local-hidden-variable model to explain the violation of our inequalities in Phys. Rev. Lett. 105, 170404 (2010). Here, we briefly discuss some issues in response to the comments raised by CS., Comment: published version
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- 2010
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19. Loophole-free Bell test for continuous variables via wave and particle correlations
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Ji, Se-Wan, Kim, Jaewan, Lee, Hai-Woong, Zubairy, M. S., and Nha, Hyunchul
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Quantum Physics - Abstract
We derive two classes of multi-mode Bell inequalities under local realistic assumptions, which are violated only by the entangled states negative under partial transposition in accordance with the Peres conjecture. Remarkably, the failure of local realism can be manifested by exploiting wave and particle correlations of readily accessible continuous-variable states, with very large violation of inequalities insensitive to detector-efficiency, which makes a strong case for a loophole-free test., Comment: 4 pages, published version
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- 2010
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20. Quantum key distribution using vacuum-one-photon qubits: maximum number of transferable bits per particle
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Lee, Su-Yong, Ji, Se-Wan, Lee, Hai-Woong, Lee, Jae-Weon, and Bergou, Janos A.
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Quantum Physics - Abstract
Quantum key distribution schemes which employ encoding on vacuum-one-photon qubits are capable of transferring more information bits per particle than the standard schemes employing polarization or phase coding. We calculate the maximum number of classical bits per particle that can be securely transferred when the key distribution is performed with the BB84 and B92 protocols, respectively, using the vacuum-one-photon qubits. In particular, we show that for a generalized B92 protocol with the vacuum-one-photon qubits, a maximum of two bits per particle can be securely transferred. We also demonstrate the advantage brought about by performing a generalized measurement that is optimized for unambiguous discrimination of the encoded states: the parameter range where the transfer of two bits per particle can be achieved is dramatically enhanced as compared to the corresponding parameter range of projective measurements., Comment: Accepted for publication in Journal of Physical Society of Japan. This paper incorporates and comprehensively extends quant-ph/0510205
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- 2009
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21. Nonclassicality generated by photon annihilation-then-creation and creation-then-annihilation operations
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Lee, Su-Yong, Park, Jiyong, Ji, Se-Wan, Ooi, C. H. Raymond, and Lee, Hai-Woong
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Quantum Physics - Abstract
We examine nonclassical properties of the field states generated by applying the photon annihilation-then-creation operation (AC) and creation-then-annihilation operation (CA) to the thermal and coherent states. Effects of repeated applications of AC and of CA are also studied. We also discuss experimental schemes to realize AC and CA with a cavity system using atom-field interactions., Comment: To be published in Journal of the Optical Society of America B
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- 2009
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22. Multi-setting Bell inequality for qudits
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Ji, Se-Wan, Lee, Jinhyoung, Lim, James, Nagata, Koji, and Lee, Hai-Woong
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Quantum Physics - Abstract
We propose a generalized Bell inequality for two three-dimensional systems with three settings in each local measurement. It is shown that this inequality is maximally violated if local measurements are configured to be mutually unbiased and a composite state is maximally entangled. This feature is similar to Clauser-Horne-Shimony-Holt inequality for two qubits but is in contrast with the two types of inequalities, Collins-Gisin-Linden-Massar-Popescu and Son-Lee-Kim, for high-dimensional systems. The generalization to aribitrary prime-dimensional systems is discussed., Comment: Accepted for publication in Phys. Rev. A
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- 2008
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23. Proposal for direct measurement of concurrence via visibility in a cavity QED system
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Lee, Sang Min, Ji, Se-Wan, Lee, Hai-Woong, and Zubairy, M. Suhail
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Quantum Physics - Abstract
An experimental scheme is proposed that allows direct measurement of the concurrence of a two-qubit cavity system. It is based on the cavity-QED technology using atoms as flying qubits and relies on the identity of the two-particle visibility of the atomic probability with the concurrence of the cavity system. The scheme works for any arbitrary pure initial state of the two-qubit cavity system., Comment: To appear in Physical Review A as a Rapid Comminication
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- 2008
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24. Analysis of Intermediate Die Profile in Multistage Shape Drawing Process Based on Two-Dimensional Electric Field Analysis: Results for Trapezoidal-Shaped Wire
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Kim, Byung Min, Lee, Kyung Hun, Oh, Sea June, Ji, Se In, Kim, Jong Sung, Duy, Vo Hoang, editor, Dao, Tran Trong, editor, Kim, Sang Bong, editor, Tien, Nguyen Tan, editor, and Zelinka, Ivan, editor
- Published
- 2017
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25. Observation of flat bands and Dirac cones in a pyrochlore lattice superconductor
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Jianwei Huang, Chandan Setty, Liangzi Deng, Jing-Yang You, Hongxiong Liu, Sen Shao, Ji Seop Oh, Yucheng Guo, Yichen Zhang, Ziqin Yue, Jia-Xin Yin, Makoto Hashimoto, Donghui Lu, Sergey Gorovikov, Pengcheng Dai, Jonathan D. Denlinger, J. W. Allen, M. Zahid Hasan, Yuan-Ping Feng, Robert J. Birgeneau, Youguo Shi, Ching-Wu Chu, Guoqing Chang, Qimiao Si, and Ming Yi
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Materials of engineering and construction. Mechanics of materials ,TA401-492 ,Atomic physics. Constitution and properties of matter ,QC170-197 - Abstract
Abstract Emergent phases often appear when the electronic kinetic energy is comparable to the Coulomb interactions. One approach to seek material systems as hosts of such emergent phases is to realize localization of electronic wavefunctions due to the geometric frustration inherent in the crystal structure, resulting in flat electronic bands. Recently, such efforts have found a wide range of exotic phases in the two-dimensional kagome lattice, including magnetic order, time-reversal symmetry breaking charge order, nematicity, and superconductivity. However, the interlayer coupling of the kagome layers disrupts the destructive interference needed to completely quench the kinetic energy. Here we demonstrate that an interwoven kagome network—a pyrochlore lattice—can host a three dimensional (3D) localization of electron wavefunctions. Meanwhile, the nonsymmorphic symmetry of the pyrochlore lattice guarantees all band crossings at the Brillouin zone X point to be 3D gapless Dirac points, which was predicted theoretically but never yet observed experimentally. Through a combination of angle-resolved photoemission spectroscopy, fundamental lattice model and density functional theory calculations, we investigate the novel electronic structure of a Laves phase superconductor with a pyrochlore sublattice, CeRu2. We observe evidence of flat bands originating from the Ce 4f orbitals as well as flat bands from the 3D destructive interference of the Ru 4d orbitals. We further observe the nonsymmorphic symmetry-protected 3D gapless Dirac cone at the X point. Our work establishes the pyrochlore structure as a promising lattice platform to realize and tune novel emergent phases intertwining topology and many-body interactions.
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- 2024
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26. Chikusetsusaponin IVa from Dolichos lablab Linne attenuates UVB-induced skin photoaging in mice by suppressing MAPK/AP-1 signaling
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Ki Mo Kim, A.-Rang Im, Ki-Shuk Shim, Chang-Seob Seo, Yongnam Lee, Jonghun Lee, Ji Seok Yoo, Sunga Choi, and Sungwook Chae
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Dolichos lablab Linne ,Ultraviolet ,Matrix metalloproteinases ,Photoaging ,Agriculture (General) ,S1-972 ,Chemistry ,QD1-999 - Abstract
Abstract Ultraviolet-B (UVB) radiation-induced photoaging of the skin is characterized by amplified expression of matrix metalloproteinase-1 (MMP-1) and reduced collagen fibers, both of which contribute to skin wrinkle formation. Edible natural products can protect against skin photoaging. Here, we investigate the protective effect of Dolichos lablab Linne (DLL) water extract against UVB radiation-prompted skin damage and attempt to uncover its fundamental mechanisms in human keratinocytes (HaCaT) and HR-1 hairless mouse. We found DLL extract rescued the reduction in cell viability associated with UVB exposure without any associated cytotoxic effects. It also protected against skin photoaging by inhibiting mitogen-activating protein kinase (MAPK) signaling, thereby preventing the UVB-associated increase in MMP-1 and -9 expression. DLL extract also increased the expression of both superoxide dismutase 1 (SOD1) and catalase (CAT). We identified chikusetsusaponin IVa, soyasaponin Bb, and sandosaponin A as bioactive components of DLL. Although we have not yet identified the mechanisms by which these compounds reduce the effects of photoaging, we have demonstrated that chikusetsusaponin IVa, soyasaponin Bb, and sandosaponin A reduce MMP-1, MMP-9, p–c-Fos, and p–c-Jun expression, while also avoiding any cytotoxicity. We found oral administration of DLL extract effectively alleviated dorsal epidermal thickening and skin dehydration in HR-1 hairless mouse visible to UVB. DLL extract also prevents UVB-induced activation of the MAPK/AP-1 signaling pathway, thereby reducing the expression of MMPs in dorsal mouse skin. Our results indicate that chikusetsusaponin IVa, soyasaponin Bb, and sandosaponin A are bioavailable components of DLL extract that can reduce UVB-induced skin damage via MMPs by deactivating the MAPK/AP-1 signaling pathway. These findings suggest DLL extract can be used as a skin anti-photoaging agent.
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- 2024
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27. Anti-protein phosphatase magnesium-dependent 1A-IgM levels in patients with active ankylosing spondylitis: a potential biomarker
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Yeo-Jin Lee, Eun-Ju Lee, Soo Min Ahn, Seokchan Hong, Ji Seon Oh, Chang-Keun Lee, Bin Yoo, and Yong-Gil Kim
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Ankylosing spondylitis ,Anti-PPM1A ,Rheumatoid arthritis ,Diagnosis ,Diseases of the musculoskeletal system ,RC925-935 ,Immunologic diseases. Allergy ,RC581-607 - Abstract
Abstract Background Ankylosing spondylitis (AS) has been known to have auto-inflammatory nature; hence, the efficacy of autoantibodies is low. However, studies on autoantibodies are ongoing, with some studies showing associations. Previous studies showed that anti-protein phosphatase magnesium-dependent 1A (PPM1A) IgG was increased in patients with AS and associated with radiographic progression. However, the diagnostic usefulness was limited due to relatively low sensitivity and specificity. This pilot study evaluated the diagnostic utility of anti-PPM1A-IgM and anti-PPM1A-IgG in patients with active AS. Methods Serum samples were obtained from the registry cohort of a single tertiary center in Korea. Serum levels of anti-PPM1A-IgG/IgM were measured by direct ELISA. Receiver operating characteristic (ROC) analysis was used to predict the diagnostic sensitivity and specificity of serum anti-PPM1A-IgG/IgM. Results Samples were collected from 28 patients with active AS, 16 healthy controls (HCs), and 28 patients with rheumatoid arthritis (RA). Although total serum IgM was lower in the RA and AS groups than in the HC group, anti-PPM1A-IgM was significantly lower in the AS group than in the other groups. In evaluating the diagnostic utility of anti-PPM1A-IgG/IgM for AS patients compared with HCs, the area under the curve (AUC) of anti-PPM1A-IgM was 0.998 (sensitivity 96.4%, specificity 100.0%). When ROC analysis of anti-PPM1A-IgM for AS patients compared with RA patients was conducted, sensitivity was 78.6% and specificity was 71.4%, with an AUC of 0.839. Conclusion Decreased anti-PPM1A-IgM levels in AS patients suggests a potential role for anti-PPM1A-IgM in the diagnosis of active AS.
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- 2024
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28. Coherent-state optical qudit cluster state generation and teleportation via homodyne detection
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Kim, Jaewan, Lee, Juhui, Ji, Se-Wan, Nha, Hyunchul, Anisimov, Petr M., and Dowling, Jonathan P.
- Published
- 2015
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29. Analysis of Intermediate Die Profile in Multistage Shape Drawing Process Based on Two-Dimensional Electric Field Analysis: Results for Trapezoidal-Shaped Wire
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Kim, Byung Min, primary, Lee, Kyung Hun, additional, Oh, Sea June, additional, Ji, Se In, additional, and Kim, Jong Sung, additional
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- 2016
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30. An Elaborated Goal Production Module for Implementing a Virtual Inhabitant
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Ji, Se-Jin, Kwon, Jung-Woo, Park, Jong-Hee, Hutchison, David, editor, Kanade, Takeo, editor, Kittler, Josef, editor, Kleinberg, Jon M., editor, Mattern, Friedemann, editor, Mitchell, John C., editor, Naor, Moni, editor, Nierstrasz, Oscar, editor, Pandu Rangan, C., editor, Steffen, Bernhard, editor, Sudan, Madhu, editor, Terzopoulos, Demetri, editor, Tygar, Dough, editor, Vardi, Moshe Y., editor, Weikum, Gerhard, editor, Carbonell, Jaime G., editor, Siekmann, Jörg, editor, Ali, Moonis, editor, and Dapoigny, Richard, editor
- Published
- 2006
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31. Risk of nosocomial coronavirus disease 2019: comparison between single- and multiple-occupancy rooms
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Hyeon Jae Jo, Pyoeng Gyun Choe, Ji Seon Kim, Mimi Lee, Minkyeong Lee, Jiyeon Bae, Chan Mi Lee, Chang Kyung Kang, Wan Beom Park, and Nam Joong Kim
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COVID-19 ,Nosocomial ,Transmission ,Respiratory virus ,Hospitals ,Infectious and parasitic diseases ,RC109-216 - Abstract
Abstract Background There is an ongoing controversy regarding whether single-occupancy rooms are superior to multiple-occupancy rooms in terms of infection prevention. We investigated whether treatment in a multiple-occupancy room is associated with an increased incidence of nosocomial coronavirus disease 2019 (COVID-19) compared with treatment in a single-occupancy room. Methods In this retrospective cohort study, every hospitalization period of adult patients aged ≥ 18 years at a tertiary hospital in Korea from January 1, 2022, to December 31, 2022, was analyzed. If COVID-19 was diagnosed more than 5 days after hospitalization, the case was classified as nosocomial. We estimated the association between the number of patients per room and the risk of nosocomial COVID-19 using a Cox proportional hazards regression model. Results In total, 25,143 hospitalizations per room type were analyzed. The incidence rate of nosocomial COVID-19 increased according to the number of patients per room; it ranged from 3.05 to 38.64 cases per 10,000 patient-days between single- and 6-bed rooms, respectively. Additionally, the hazard ratios of nosocomial COVID-19 showed an increasing trend according to the number of patients per room, ranging from 0.14 (95% confidence interval 0.001–1.03) to 2.66 (95% confidence interval 1.60–4.85) between single- and 6-bed rooms, respectively. Conclusions We demonstrated that the incidence of nosocomial COVID-19 increased according to the number of patients per room. To reduce nosocomial infections by respiratory viruses, the use of multiple-occupancy rooms should be minimized.
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- 2024
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32. Expression of CD163 and major histocompatibility complex class I as diagnostic markers for idiopathic inflammatory myopathies
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Byeongzu Ghang, So Hye Nam, Wonho Choi, Hwa Jung Kim, Jungsun Lee, Doo-Ho Lim, Soo Min Ahn, Ji Seon Oh, Seokchan Hong, Yong-Gil Kim, Chang-Keun Lee, Jinseok Kim, Bin Yoo, and Soo Jeong Nam
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Myositis ,CD163 antigen ,Histocompatibility antigens class I ,Immunohistochemistry ,Diseases of the musculoskeletal system ,RC925-935 - Abstract
Abstract Background To develop an inflammation-related immunohistochemistry marker-based algorithm that confers higher diagnostic ability for idiopathic inflammatory myopathies (IIMs) than IIM-related histopathologic features. Methods Muscle biopsy tissues from 129 IIM patients who met the 2017 EULAR/ACR criteria and 73 control tissues from patients with non-inflammatory myopathies or healthy muscle specimens were evaluated for histological features and immunostaining results of CD3, CD4, CD8, CD20, CD68, CD163, MX1, MHC class I, MHC class II, and HLA-DR. Diagnostic algorithms for IIM were developed based on the results of the classification and regression tree (CART) analysis, which used immunostaining results as predictor variables for classifying patients with IIMs. Results In the analysis set (IIM, n = 129; control, n = 73), IIM-related histopathologic features had a diagnostic accuracy of 87.6% (sensitivity 80.6%; specificity 100.0%) for IIMs. Notably, muscular expression of CD163 (99.2% vs. 20.8%, p
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- 2024
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33. Effect of remimazolam versus propofol anesthesia on postoperative delirium in neurovascular surgery: study protocol for a randomized controlled, non-inferiority trial
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Jeayoun Kim, Seungwon Lee, Boram Park, Woo Seog Sim, Hyun Joo Ahn, Mi-Hye Park, and Ji Seon Jeong
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Neurosurgery ,Neurovascular surgery ,Postoperative cognitive dysfunction ,Postoperative delirium ,Propofol ,Remimazolam ,Surgery ,RD1-811 - Abstract
Abstract Background Remimazolam is a short-acting benzodiazepine newly approved for the induction and maintenance of general anesthesia. Remimazolam emerges as an ideal drug for the neurosurgical population due to its rapid emergence, enabling early neurological assessment, and its ability to maintain perfusion pressure, which is crucial for preventing cerebral ischemia. However, the use of benzodiazepine has been associated with an increased risk of postoperative delirium (POD). There is currently limited evidence about the relationship between remimazolam-based total intravenous anesthesia (TIVA) and POD. Methods In this double-blind, randomized, non-inferiority trial, we plan to include 696 adult patients with American Society of Anesthesiologists physical status class I to III, undergoing elective neurovascular surgery under general anesthesia. After informed consent, the patients will be randomized to receive either remimazolam or propofol-based TIVA with a 1:1 ratio. The primary outcome is the incidence of POD within 5 days after surgery. Secondary outcomes include subtypes, number of positive assessments and severity of POD, emergence agitation, intraoperative awareness and undesirable patient movement, intraoperative hypotension, and postoperative cognitive function. The data will be analyzed in modified intention to treat. Discussion This trial will evaluate the effect of remimazolam on the development of POD compared to propofol anesthesia. The results of this trial will provide evidence regarding the choice of optimal anesthetics to minimize the risk of POD in neurosurgical patients. Trial registration The study protocol was prospectively registered at the Clinical trials ( https://clinicaltrials.gov , NCT06115031, principal investigator: Jiseon Jeong; date of first registration: November 2, 2023, before the recruitment of the first participant.
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- 2024
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34. Drug survival and change of disease activity using a second janus kinase inhibitor in patients with difficult-to-treat rheumatoid arthritis who failed to a janus kinase inhibitor and subsequent biologics
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Oh Chan Kwon, Wonho Choi, Soo Min Ahn, Ji Seon Oh, Seokchan Hong, Chang-Keun Lee, Bin Yoo, Min-Chan Park, and Yong-Gil Kim
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Rheumatoid arthritis ,Janus kinase inhibitor, switching ,Drug survival ,Effectiveness ,Diseases of the musculoskeletal system ,RC925-935 ,Immunologic diseases. Allergy ,RC581-607 - Abstract
Abstract Background To assess the drug survival and change of disease activity using a second Janus kinase inhibitor (JAKi) after failure to a JAKi and subsequent biologic disease-modifying anti-rheumatic drugs (bDMARDs) in patients with difficult-to-treat rheumatoid arthritis (RA). Methods This retrospective cohort study included 32 patients with difficult-to-treat RA who failed to a JAKi and subsequently to one or more bDMARDs and then switched to a second JAKi. To assess drug survival, electronic medical records of each patient were reviewed. Data on whether the second JAKi was discontinued, and the reasons for discontinuation were collected. The change of disease activity was assessed by analyzing changes in tender joint count (TJC), swollen joint count (SJC), patient’s global assessment of disease activity on a visual-analogue scale (VAS), erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), Disease Activity Score for 28 joints with ESR (DAS28-ESR), and DAS28-CRP from baseline to that at six months from initiation of the second JAKi. Results Overall, discontinuation of the second JAKi occurred in 20 (62.5%) patients. Primary failure, secondary failure, adverse events, and insurance coverage issues were the reasons for discontinuation in 9 (45.0%), 5 (25.0%), 2 (10.0%), and 4 (20.0%) patients, respectively. The estimated 2-year drug survival rate was 39.3%. In terms of change of disease activity, the second JAKi significantly improved TJC (p
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- 2024
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35. Reversible non-volatile electronic switching in a near-room-temperature van der Waals ferromagnet
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Han Wu, Lei Chen, Paul Malinowski, Bo Gyu Jang, Qinwen Deng, Kirsty Scott, Jianwei Huang, Jacob P. C. Ruff, Yu He, Xiang Chen, Chaowei Hu, Ziqin Yue, Ji Seop Oh, Xiaokun Teng, Yucheng Guo, Mason Klemm, Chuqiao Shi, Yue Shi, Chandan Setty, Tyler Werner, Makoto Hashimoto, Donghui Lu, Turgut Yilmaz, Elio Vescovo, Sung-Kwan Mo, Alexei Fedorov, Jonathan D. Denlinger, Yaofeng Xie, Bin Gao, Junichiro Kono, Pengcheng Dai, Yimo Han, Xiaodong Xu, Robert J. Birgeneau, Jian-Xin Zhu, Eduardo H. da Silva Neto, Liang Wu, Jiun-Haw Chu, Qimiao Si, and Ming Yi
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Science - Abstract
Abstract Non-volatile phase-change memory devices utilize local heating to toggle between crystalline and amorphous states with distinct electrical properties. Expanding on this kind of switching to two topologically distinct phases requires controlled non-volatile switching between two crystalline phases with distinct symmetries. Here, we report the observation of reversible and non-volatile switching between two stable and closely related crystal structures, with remarkably distinct electronic structures, in the near-room-temperature van der Waals ferromagnet Fe5−δ GeTe2. We show that the switching is enabled by the ordering and disordering of Fe site vacancies that results in distinct crystalline symmetries of the two phases, which can be controlled by a thermal annealing and quenching method. The two phases are distinguished by the presence of topological nodal lines due to the preserved global inversion symmetry in the site-disordered phase, flat bands resulting from quantum destructive interference on a bipartite lattice, and broken inversion symmetry in the site-ordered phase.
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- 2024
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36. Assessment of process-induced cracks in hot-working operations using crack susceptibility index based on plastic instability criteria
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M.S. Lee, Ji Seob An, Sun Kwang Hwang, Min-Churl Song, and Young Hoon Moon
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Crack susceptibility index ,Deformation processing map ,Plastic instability criteria ,Ziegler's parameter ,Hot working ,Mining engineering. Metallurgy ,TN1-997 - Abstract
A processing map representing the efficiency of power dissipation as a function of the temperature and strain rate has been used as a guide to depict the hot workability of metallic alloys. However, it has limitations in indicating the local positions where process-induced cracks may occur during hot-working operations. A process-induced crack is formed during hot deformation because the plastic instability associated with crack formation is more favorable than normal flow under a given set of process conditions. This paper proposes a novel approach to assess local cracks using the crack susceptibility index (CSI), which is based on Ziegler's plastic instability criteria. This solution provides useful information regarding the effect of each process parameter on the workability required for high-temperature processes. Lowering the CSI value by controlling process variables, such as the temperature and strain rate, is recommended for a design free from process-induced cracks. More importantly, a coded finite element subroutine coupled with the CSI can help visualize local positions where cracks may be produced during a hot-working operation. For experimental validation, a Gleeble test was performed on Ti6Al4V specimens containing four notches with different depths. The successful application of the CSI to the process design of shop-floor unmanned aircraft components helped confirm the applicability and validity of this study.
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- 2024
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37. Numb-associated kinases regulate sandfly-borne Toscana virus entry
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Yarden Moalem, Rodolfo Katz, Anand G. Subramaniam, Yehonathan Malis, Yakey Yaffe, Nofit Borenstein-Auerbach, Keshet Tadmor, Roey Raved, Ben M. Maoz, Ji Seung Yoo, Yaniv Lustig, Chen Luxenburg, Eran Perlson, Shirit Einav, and Ella H. Sklan
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Toscana virus ,Sandfly ,Phleboviruses ,Bunyaviruses ,viral entry ,Infectious and parasitic diseases ,RC109-216 ,Microbiology ,QR1-502 - Abstract
Sandfly-borne Toscana virus (TOSV) is an enveloped tri-segmented negative single-strand RNA Phlebovirus. It is an emerging virus predominantly endemic in southwestern Europe and Northern Africa. Although TOSV infection is typically asymptomatic or results in mild febrile disease, it is neurovirulent and ranks among the three most common causes of summer meningitis in certain regions. Despite this clinical significance, our understanding of the molecular aspects and host factors regulating phlebovirus infection is limited. This study characterized the early steps of TOSV infection. Our findings reveal that two members of the Numb-associated kinases family of Ser/Thr kinases, namely adaptor-associated kinase 1 (AAK1) and cyclin G-associated kinase (GAK), play a role in regulating the early stages of TOSV entry. FDA-approved inhibitors targeting these kinases demonstrated significant inhibition of TOSV infection. This study suggests that AAK1 and GAK represent druggable targets for inhibiting TOSV infection and, potentially, related Phleboviruses.
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- 2024
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38. Effects of high tibial osteotomy on the coronal, sagittal, and axial alignments of the ankle joint
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Byung Hak Oh, Kyung Deok Seo, Hyun Jin Yoo, Min Gu Jang, Ji Seong Park, and Jae Hwang Song
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Orthopedic surgery ,RD701-811 - Abstract
Background No comprehensive study has been conducted on the effects of high tibial osteotomy (HTO) on the coronal, sagittal, and axial alignments of the ankle joint. Therefore, this study aimed to investigate the multiplane changes in the ankle joint following HTO using the EOS biplanar X-ray imaging system. Methods The medical records of 43 patients who underwent HTO for the treatment of medial knee osteoarthritis were retrospectively reviewed. Preoperative and postoperative EOS images and lower-extremity scanograms were evaluated; the correlations between the outcomes were evaluated. Results After HTO, the ankle joint axis point on the weight-bearing line showed significant lateralization ( p < .001). The knee lateral ankle surface angle increased significantly in the sagittal alignment ( p < .001). The distal tibia showed a significant internal rotation in the axial plane ( p = .022). Tibial rotation showed no significant relationship with the other parameters. Conclusions HTO induced lateralization of the ankle joint axis (coronal), increased the posterior tibial slope (sagittal), and caused the internal rotation of the distal tibia (axial). Axial changes in the distal tibia showed no significant relationship with other coronal and sagittal parameters of the ankle joint. We suggest that surgeons should consider, during HTO, that the ankle joint axis shifts laterally and distal tibia has tendency to rotate internally after HTO.
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- 2024
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39. Calsyntenins Function as Synaptogenic Adhesion Molecules in Concert with Neurexins
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Ji Won Um, Gopal Pramanik, Ji Seung Ko, Min-Young Song, Dongmin Lee, Hyun Kim, Kang-Sik Park, Thomas C. Südhof, Katsuhiko Tabuchi, and Jaewon Ko
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Biology (General) ,QH301-705.5 - Published
- 2024
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40. Whole-genome sequences reveal zygotic composition in chimeric twins
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Christopher J. Yoon, Chang Hyun Nam, Taewoo Kim, Jeong Seok Lee, Ryul Kim, Kijong Yi, June-Young Koh, Jiye Kim, Hyein Won, Ji Won Oh, Obi L. Griffith, Malachi Griffith, Joohon Sung, Tae Yeul Kim, Duck Cho, Ji Seon Choi, and Young Seok Ju
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monochorionic dizygotic twins ,chimera ,single-cell sequencing ,lineage tracing ,de novo mutation ,Genetics ,QH426-470 - Abstract
Summary: While most dizygotic twins have a dichorionic placenta, rare cases of dizygotic twins with a monochorionic placenta have been reported. The monochorionic placenta in dizygotic twins allows in utero exchange of embryonic cells, resulting in chimerism in the twins. In practice, this chimerism is incidentally identified in mixed ABO blood types or in the presence of cells with a discordant sex chromosome. Here, we applied whole-genome sequencing to one triplet and one twin family to precisely understand their zygotic compositions, using millions of genomic variants as barcodes of zygotic origins. Peripheral blood showed asymmetrical contributions from two sister zygotes, where one of the zygotes was the major clone in both twins. Single-cell RNA sequencing of peripheral blood tissues further showed differential contributions from the two sister zygotes across blood cell types. In contrast, buccal tissues were pure in genetic composition, suggesting that in utero cellular exchanges were confined to the blood tissues. Our study illustrates the cellular history of twinning during human development, which is critical for managing the health of chimeric individuals in the era of genomic medicine.
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- 2024
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41. Ubiquitin ligase RNF20 coordinates sequential adipose thermogenesis with brown and beige fat-specific substrates
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Yong Geun Jeon, Hahn Nahmgoong, Jiyoung Oh, Dabin Lee, Dong Wook Kim, Jane Eunsoo Kim, Ye Young Kim, Yul Ji, Ji Seul Han, Sung Min Kim, Jee Hyung Sohn, Won Taek Lee, Sun Won Kim, Jeu Park, Jin Young Huh, Kyuri Jo, Je-Yoel Cho, Jiyoung Park, and Jae Bum Kim
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Science - Abstract
Abstract In mammals, brown adipose tissue (BAT) and inguinal white adipose tissue (iWAT) execute sequential thermogenesis to maintain body temperature during cold stimuli. BAT rapidly generates heat through brown adipocyte activation, and further iWAT gradually stimulates beige fat cell differentiation upon prolonged cold challenges. However, fat depot-specific regulatory mechanisms for thermogenic activation of two fat depots are poorly understood. Here, we demonstrate that E3 ubiquitin ligase RNF20 orchestrates adipose thermogenesis with BAT- and iWAT-specific substrates. Upon cold stimuli, BAT RNF20 is rapidly downregulated, resulting in GABPα protein elevation by controlling protein stability, which stimulates thermogenic gene expression. Accordingly, BAT-specific Rnf20 suppression potentiates BAT thermogenic activity via GABPα upregulation. Moreover, upon prolonged cold stimuli, iWAT RNF20 is gradually upregulated to promote de novo beige adipogenesis. Mechanistically, iWAT RNF20 mediates NCoR1 protein degradation, rather than GABPα, to activate PPARγ. Together, current findings propose fat depot-specific regulatory mechanisms for temporal activation of adipose thermogenesis.
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- 2024
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42. Nanoscale visualization and spectral fingerprints of the charge order in ScV6Sn6 distinct from other kagome metals
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Siyu Cheng, Zheng Ren, Hong Li, Ji Seop Oh, Hengxin Tan, Ganesh Pokharel, Jonathan M. DeStefano, Elliott Rosenberg, Yucheng Guo, Yichen Zhang, Ziqin Yue, Yongbin Lee, Sergey Gorovikov, Marta Zonno, Makoto Hashimoto, Donghui Lu, Liqin Ke, Federico Mazzola, Junichiro Kono, R. J. Birgeneau, Jiun-Haw Chu, Stephen D. Wilson, Ziqiang Wang, Binghai Yan, Ming Yi, and Ilija Zeljkovic
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Materials of engineering and construction. Mechanics of materials ,TA401-492 ,Atomic physics. Constitution and properties of matter ,QC170-197 - Abstract
Abstract Charge density waves (CDWs) in kagome metals have been tied to many exotic phenomena. Here, using spectroscopic-imaging scanning tunneling microscopy and angle-resolved photoemission spectroscopy, we study the charge order in kagome metal ScV6Sn6. The similarity of electronic band structures of ScV6Sn6 and TbV6Sn6 (where charge ordering is absent) suggests that charge ordering in ScV6Sn6 is unlikely to be primarily driven by Fermi surface nesting of the Van Hove singularities. In contrast to the CDW state of cousin kagome metals, we find no evidence supporting rotation symmetry breaking. Differential conductance dI/dV spectra show a partial gap Δ 1 CO ≈ 20 meV at the Fermi level. Interestingly, dI/dV maps reveal that charge modulations exhibit an abrupt phase shift as a function of energy at energy much higher than Δ 1 CO, which we attribute to another spectral gap. Our experiments reveal a distinctive nature of the charge order in ScV6Sn6 with fundamental differences compared to other kagome metals.
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- 2024
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43. Ultrasound biomicroscopy analysis of ciliary muscle dynamics and its relation to intra-ocular pressure after phacoemulsification in dogs
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Donghee Kim, Sang-Eun Park, Jiyi Hwang, Nanyoung Kang, Ji Seung Jung, and Kyung-Mee Park
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ciliary cleft ,ciliary body ,ciliary muscle ,phacoemulsification ,glaucoma ,ultrasound biomicroscopy ,Veterinary medicine ,SF600-1100 - Abstract
IntroductionThis study investigates the relationship between ciliary muscle dynamics, thickness, and the regulation of intraocular pressure (IOP), focusing on the progression of cataracts and changes post-phacoemulsification. It explores how these factors impact canine ocular health, particularly in the context of cataract development and subsequent surgical intervention.Materials and methodsData was collected using Ultrasound Biomicroscopy (UBM) from dogs at the Veterinary Medical Teaching Hospital of Chungbuk National University, Korea. The study involved 57 eyes from 35 dogs, categorized into five groups: 13 normal eyes, 14 with incipient cataracts, 12 with immature cataracts, 6 with mature cataracts, and 12 post-phacoemulsification. UBM measurements assessed various ciliary muscle parameters including ciliary body axial length (CBAXL), ciliary process-sclera angle (CPSA), longitudinal fibers of ciliary muscle thickness (Lf-CMT), and longitudinal and radial fibers of ciliary muscle thickness (LRf-CMT).ResultsFindings indicated a decrease in CBAXL and an increase in Lf-CMT as cataracts progressed in severity. Post-phacoemulsification, there was a notable increase in CBAXL and a decrease in CPSA, Lf-CMT, and LRf-CMT, compared to both cataractous and normal eyes. Regression analysis revealed a significant positive association between CBAXL and IOP, alongside a negative association between Lf-CMT and IOP. These findings suggest that variations in ciliary muscle dynamics and thickness, as influenced by cataract progression and phacoemulsification, have distinct impacts on intraocular pressure.DiscussionThe study proposes that phacoemulsification leads to ciliary muscle contraction, causing an inward and anterior movement of the ciliary muscle. This movement results in the narrowing of the ciliary cleft and constriction of the unconventional outflow pathway, potentially causing an increased risk of glaucoma post-surgery. Our research contributes to understanding the anatomical and physiological changes in the canine eye following cataract surgery and underscores the importance of monitoring IOP and ciliary muscle dynamics in these patients.
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- 2024
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44. Qualitative evaluation of artificial intelligence-generated weight management diet plans
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Dong Wook Kim, Ji Seok Park, Kavita Sharma, Amanda Velazquez, Lu Li, John W. Ostrominski, Tram Tran, Robert H. Seitter Peréz, and Jeong-Hun Shin
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AI ,diet plan ,weight management ,ChatGPT ,dietary intervention ,Nutrition. Foods and food supply ,TX341-641 - Abstract
ImportanceThe transformative potential of artificial intelligence (AI), particularly via large language models, is increasingly being manifested in healthcare. Dietary interventions are foundational to weight management efforts, but whether AI techniques are presently capable of generating clinically applicable diet plans has not been evaluated.ObjectiveOur study sought to evaluate the potential of personalized AI-generated weight-loss diet plans for clinical applications by employing a survey-based assessment conducted by experts in the fields of obesity medicine and clinical nutrition.Design, setting, and participantsWe utilized ChatGPT (4.0) to create weight-loss diet plans and selected two control diet plans from tertiary medical centers for comparison. Dietitians, physicians, and nurse practitioners specializing in obesity medicine or nutrition were invited to provide feedback on the AI-generated plans. Each plan was assessed blindly based on its effectiveness, balanced-ness, comprehensiveness, flexibility, and applicability. Personalized plans for hypothetical patients with specific health conditions were also evaluated.Main outcomes and measuresThe primary outcomes measured included the indistinguishability of the AI diet plan from human-created plans, and the potential of personalized AI-generated diet plans for real-world clinical applications.ResultsOf 95 participants, 67 completed the survey and were included in the final analysis. No significant differences were found among the three weight-loss diet plans in any evaluation category. Among the 14 experts who believed that they could identify the AI plan, only five did so correctly. In an evaluation involving 57 experts, the AI-generated personalized weight-loss diet plan was assessed, with scores above neutral for all evaluation variables. Several limitations, of the AI-generated plans were highlighted, including conflicting dietary considerations, lack of affordability, and insufficient specificity in recommendations, such as exact portion sizes. These limitations suggest that refining inputs could enhance the quality and applicability of AI-generated diet plans.ConclusionDespite certain limitations, our study highlights the potential of AI-generated diet plans for clinical applications. AI-generated dietary plans were frequently indistinguishable from diet plans widely used at major tertiary medical centers. Although further refinement and prospective studies are needed, these findings illustrate the potential of AI in advancing personalized weight-centric care.
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- 2024
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45. Polygenic Scores Clarify the Relationship Between Mental Health and Gender Diversity
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Taylor R. Thomas, Ashton J. Tener, Amy M. Pearlman, Katherine L. Imborek, Ji Seung Yang, John F. Strang, and Jacob J. Michaelson
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Autism ,Gender ,LGBTQ ,Mental health ,Psychiatry ,RC435-571 - Abstract
Background: Gender-diverse individuals are at increased risk for mental health problems, but it is unclear whether this is due to shared environmental or genetic factors. Methods: In two SPARK samples, we tested for associations of 16 polygenic scores (PGSs) with quantitative measures of gender diversity and mental health. In study 1, 639 independent adults (59% autistic) reported their mental health with the Adult Self-Report and their gender diversity with the Gender Self-Report (GSR). The GSR has 2 dimensions: binary (degree of identification with the gender opposite that implied by sex designated at birth) and nonbinary (degree of identification with a gender that is neither male nor female). In study 2 (N = 5165), we used a categorical measure of gender identity. Results: In study 1, neuropsychiatric PGSs were positively associated with Adult Self-Report scores: externalizing was positively associated with the attention-deficit/hyperactivity disorder PGS (β = 0.10 [0.03–0.17]), and internalizing was positively associated with the PGSs for depression (β = 0.07 [0–0.14]) and neuroticism (β = 0.10 [0.03–0.17]). Interestingly, GSR scores were not significantly associated with any neuropsychiatric PGS. However, GSR nonbinary was positively associated with the cognitive performance PGS (β = 0.11 [0.05–0.18]), with the effect size comparable in magnitude to the associations of the neuropsychiatric PGSs with the Adult Self-Report. Additionally, GSR binary was positively associated with the nonheterosexual sexual behavior PGS (β = 0.07 [0–0.14]). In study 2, the cognitive performance PGS effect replicated; transgender and nonbinary individuals had higher PGSs (t316 = 4.16). Conclusions: We showed that while gender diversity is phenotypically positively associated with mental health problems, the strongest PGS associations with gender diversity were with the cognitive performance PGS, not the neuropsychiatric PGSs.
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- 2024
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46. Deterministic Secure Quantum Communication on the BB84 System
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Jeong, Youn-Chang, primary, Ji, Se-Wan, additional, Hong, Changho, additional, Park, Hee Su, additional, and Jang, Jingak, additional
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- 2020
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47. Diversity of Nigrospora (Xylariales, Apiosporaceae) Species Identified in Korean Macroalgae Including Five Unrecorded Species
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Wonjun Lee, Dong-Geon Kim, Rekhani H. Perera, Ji Seon Kim, Yoonhee Cho, Jun Won Lee, Chang Wan Seo, and Young Woon Lim
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Marine fungi ,taxonomy ,seaweed ,algicolous fungi ,Ascomycota ,Botany ,QK1-989 - Abstract
AbstractNigrospora (Xylariales, Apiosporaceae) consists of species of terrestrial plant endophytes and pathogens. Nigrospora has also been reported in marine environments such as mangroves, sea fans, and macroalgae. However, limited research has been conducted on Nigrospora associated with macroalgae. Here, we isolated Nigrospora species from three types of algae (brown, green, and red algae) from Korean islands (Chuja, Jeju, and Ulleung) based on phylogenetic analyses of multigenetic markers: the internal transcribed spacers (ITS), beta-tubulin (BenA), and translation elongation factor 1 (TEF1-α). A total of 17 Nigrospora strains were isolated from macroalgae and identified as nine distinct species. The majority of Nigrospora species (seven) were found on brown algae, followed by red algae (three), and then green algae (two). To our understanding, this study represents the first account of N. cooperae, N. covidalis, N. guilinensis, N. lacticolonia, N. osmanthi, N. pyriformis, and N. rubi occurring in marine environments. Additionally, this study provides the first report of the occurrence of N. cooperae, N. covidalis, N. guilinensis, N. lacticolonia, and N. osmanthi in South Korea. This study will provide valuable insights for future research exploring the functions of fungi in macroalgal communities.
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- 2023
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48. Comparable Outcomes of Bicuspid Aortic Valves for Rapid- Deployment Aortic Valve Replacement
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Somin Im, Kyung Hwan Kim, Suk Ho Sohn, Yoonjin Kang, Ji Seong Kim, and Jae Woong Choi
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aortic valve replacement ,rapid-deployment valve ,bicuspid aortic valve ,outcomes ,paravalvular leakage ,Medicine (General) ,R5-920 - Abstract
Background: Edwards Intuity is recognized as a relatively contraindicated bioprosthesis for bicuspid aortic valve disease. This study compared the early echocardiographic and clinical outcomes of rapid-deployment aortic valve replacement for bicuspid versus tricuspid aortic valves. Methods: Of 278 patients who underwent rapid-deployment aortic valve replacement using Intuity at Seoul National University Hospital, 252 patients were enrolled after excluding those with pure aortic regurgitation, prosthetic valve failure, endocarditis, and quadricuspid valves. The bicuspid and tricuspid groups included 147 and 105 patients, respectively. Early outcomes and the incidence of paravalvular leak were compared between the groups. A subgroup analysis compared the outcomes for type 0 versus type 1 or 2 bicuspid valves. Results: The bicuspid group had more male and younger patients. Comorbidities, including diabetes mellitus, hypertension, chronic kidney disease, and coronary artery disease, were less prevalent in the bicuspid group. Early echocardiographic evaluations demonstrated that the incidence of ≥mild paravalvular leak did not differ significantly between the groups (5.5% vs. 1.0% in the bicuspid vs. tricuspid groups, p=0.09), and the early clinical outcomes were also comparable between the groups. In the subgroup analysis between type 0 and type 1 or 2 bicuspid valves, the incidence of mild or greater paravalvular leak (2.4% vs. 6.7% in type 0 vs. type 1 or 2, p=0.34) and clinical outcomes were comparable. Conclusion: Rapid-deployment aortic valve replacement for bicuspid aortic valves demonstrated comparable early echocardiographic and clinical outcomes to those for tricuspid aortic valves, and the outcomes were also satisfactory for type 0 bicuspid aortic valves.
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- 2023
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49. Modified cervicofacial transposition flap: a case report of aesthetic considerations after resection of a huge facial squamous cell carcinoma
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Young Jun Kim, Ji Seon Cheon, Min Hyub Choi, and Woo Young Choi
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cheek reconstruction ,expanded cervicofacial flap ,squamous cell carcinoma ,surgical flaps ,superficial musculooponeurotic system ,Surgery ,RD1-811 - Abstract
The cheek, a highly visible and significant aspect of an individual’s appearance, is situated adjacent to several structures involved in facial expressions, including the eye, mouth, and surrounding facial muscles. Consequently, aesthetic reconstruction for large cutaneous defects of the cheek remains a challenge for plastic surgeons. We experienced a case of an 83-year-old woman with a large (7×10 cm) facial defect following the removal of squamous cell carcinoma. We elevated a cervicofacial skin flap containing the superficial layer of the superficial musculoaponeurotic system and a blood supply via the dermal plexus in a random pattern. Through this method, we achieved aesthetically favorable reconstruction of a large facial defect using a cervicofacial transposition skin flap. By avoiding extensive dissection, we achieved adequate coverage for even a quite sizable facial defect, with a short recovery time. This method prevented facial nerve injury and made it possible to simultaneously obtain an aesthetically favorable outcome.
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- 2023
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50. Unveiling the Diversity of Hydnum in the Republic of Korea with One New Species, Hydnum paucispinum
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Ji Seon Kim, Wonjun Lee, Changmu Kim, Hanna Park, Chang Sun Kim, and Young Woon Lim
- Subjects
Hydnum ,Hydnaceae ,ectomycorrhiza ,sequence-based identification ,Botany ,QK1-989 - Abstract
AbstractHydnum is a genus of ectomycorrhizal fungi belonging to the Hydnaceae family. It is widely distributed across different regions of the world, including North America, Europe, and Asia; however, some of them showed disjunct distributions. In recent years, with the integration of molecular techniques, the taxonomy and classification of Hydnum have undergone several revisions and advancements. However, these changes have not yet been applied in the Republic of Korea. In this study, we conducted an integrated analysis combining the morphological and molecular analyses of 30 specimens collected over a period of approximately 10 years in the Republic of Korea. For molecular analysis, the sequence data of the internal transcribed spacer (ITS) region, the large subunit of nuclear ribosomal RNA gene (nrLSU), and a portion of translation elongation factor 1-α (TEF1) were employed as molecular markers. Through this study, we identified eight species that had previously not been reported to occur in the Republic of Korea, including one new species, Hydnum paucispinum. A taxonomic key and detailed descriptions of the eight Hydnum species are provided in this study.
- Published
- 2023
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