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In addition to secret splitting, secret reconstruction is another important component of secret sharing. In this paper, the first quantum secret reconstruction protocol is proposed to protect the reconstruction process. Before the protocol, a classical secret is divided into multiple shares that are distributed to the shareholds, respectively. In the presented protocol, the dealer utilizes the secret to encrypt a privacy quantum state, and sends the encrypted state to a combiner who is chosen by the dealer within the shareholders. With the help of other shareholders, the combiner utilizes the properties of cluster states to recover the privacy quantum state. It is shown that the proposed protocol is secure against several common attacks, including external and internal attacks. Compared with classical secret reconstruction protocols, this protocol not only achieves information‐theoretic security of all shares, but is also more efficient due to the reduced distribution and computation cost. To demonstrate the feasibility of the protocol, a corresponding simulation quantum experiment is conducted on the IBM Q. Furthermore, in conjunction with quantum fingerprinting, it can be directly applied to achieve the task of quantum multiple secrets sharing, since the classical shares can be reused in the proposed protocol. [ABSTRACT FROM AUTHOR]

Generalized Feistel schemes (GFSs) are extremely important and extensively researched cryptographic schemes. In this paper, the security of Type‐1 GFS in quantum circumstances is investigated. On the one hand, in the qCCA setting, a new quantum polynomial‐time distinguisher on (d2−1)$(d^2-1)$‐round Type‐1 GFS with branches d≥3$d\ge 3$ is given, which extends the previous results by (d−2)$(d-2)$ rounds. This leads to a more efficient analysis of type‐1 GFS, that is, the complexity of some previous key‐recovery attacks is reduced by a factor of 2(d−2)k2$2^{\frac{(d-2)k}{2}}$, where k is the key length of the internal round function. On the other hand, for CAST‐256, which is a certain block cipher based on Type‐1 GFS, a 17‐round quantum distinguisher in the qCPA setting is given. Based on this, an r(r>17)$r (r>17)$‐round quantum key‐recovery attack with complexity O(237(r−17)2)$O(2^{\frac{37(r-17)}{2}})$ is constructed. [ABSTRACT FROM AUTHOR]

By introducing the BHT algorithm into the slide attack on 1K-AES and the related-key attack on PRINCE, we present the corresponding quantum attacks in this paper. In the proposed quantum attacks, we generalize the BHT algorithm to the situation where the number of marked items is unknown ahead of time. Moreover, we give an implementation scheme of classifier oracle based on Quantum Phase Estimation algorithm in presented quantum attacks. The complexity analysis shows that the query complexity, time complexity and memory complexity of the presented quantum attacks are all |$\mathcal{O}(2^{n/3})$| when the success probability is about |$63\%$|⁠ , where |$n$| is the block size. Compared with the corresponding classical attacks, the proposed quantum attacks can achieve subquadratic speed-up under the same success probability no matter on query complexity, time complexity or memory complexity. Furthermore, the query complexity of the proposed quantum slide attack on 1K-AES is less than Grover search on 1K-AES by a factor of |$2^{n/6}.$| When compared with the Grover search on PRINCE, the query complexity of the presented quantum attack on PRINCE is reduced from |$\mathcal{O}(2^{n})$| to |$\mathcal{O}(2^{n/2}).$| When compared with the combination of Grover and Simon's algorithms on PRINCE, the query complexity of our quantum attack on PRINCE is reduced from |$\mathcal{O}(n\cdot 2^{n/2})$| to |$\mathcal{O}(2^{n/2}).$| Besides, the proposed quantum slide attack on 1K-AES indicates that the quantum slide attack could also be applied on Substitution-Permutation Network construction, apart from the iterated Even-Mansour cipher and Feistel constructions. [ABSTRACT FROM AUTHOR]

Three new metal-organic coordination polymers, namely {[Cu(4,4'-bipy)(5-Hoipa)2](H2O)2}n (I, 5-H2oipa = 5-Hydroxyisophthalicacid, 4,4'-bipy = 4,4'-bipyridine), {[Cu2(4,4'-bipy)(tzb)2](DMF)3} (II, H2tzb = 4-(1H-Tetrazol-5-yl)benzoic acid), and {[Cu(cpdba)(2,2′—bpy)]}n (III, H2cpdba = 4-(4-carboxyphenylamino)-3,5-dinitrobenzoic acid, 2,2'-bipy = 2,2'-bipyridine), have been successfully prepared by using two similar pyridine ligands with different co-ligands under different reaction conditions (slow volatilization for II, solvothermal for I and III). Their structures have been unambiguously determined by both single-crystal X-ray study and elemental analysis. Additionally, the newly synthesized compounds were evaluated to identify the molecular characteristics contributing to their cytotoxicity. They were tested against three human gastric cancer cells (MGC-803, SGC-790 and MKN45) with the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay. [ABSTRACT FROM AUTHOR]