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From Wall Street to City Hall, government financial whiz Diana Taylor brings patrician elegance to the world of business dressing. And for nights on the arm of Mayor Michael Bloomberg, she's expanding her repertoire of life-in-the-spotlight dresses.

The Kyrenia Ship, found off the north coast of Cyprus, is a key vessel in the history of scientific underwater excavations and in the history of Greek shipbuilding. The first volume of the site’s final publication appeared in 2023 and provides detailed archaeological information tightly constraining the dating of the ship. A very specific date range is proposed: ca. 294–290 BCE, but is based on a less than certain reading of one coin recovered from the ship. While there is clear benefit to finding high-precision dates for the Kyrenia Ship and its rich assemblage using independent scientific dating (combined with Bayesian chronological modeling), efforts to do so proved more challenging and complex than initially anticipated. Strikingly, extensive radiocarbon dating on both wooden materials from the ship and on short-lived contents from the final use of the ship fail to offer dates using the IntCal20 calibration curve—the current Northern Hemisphere radiocarbon calibration curve at the time of writing—that correspond with the archaeological constraints. The issue rests with a segment of IntCal20 ca. 350–250 BCE reliant on legacy pre-AMS radiocarbon data. We therefore measured new known-age tree-ring samples 350–250 BCE, and, integrating another series of new known-age tree-ring data, we obtained a redefined and more accurate calibration record for the period 433–250 BCE. These new data permit a satisfactory dating solution for the ship and may even indicate a date that is a (very) few years more recent than current estimations. These new data in addition confirm and only very slightly modify the dating recently published for the Mazotos ship, another Greek merchant ship from the southern coast of Cyprus. Our work further investigated whether ship wood samples impregnated with a common preservative, polyethylene glycol (PEG), can be cleaned successfully, including a known-age test.

Mixing serves as an effective method to safeguard the privacy of nodes in digital currency systems by introducing a mixer to break the link between transaction inputs and outputs. Existing mixing schemes heavily rely on stringent security assumptions to prevent potential risks, including privacy breaches and coin loss. Recognizing this concern, we propose DcMix, a decentralized private coin mixing scheme that ensures unconditional anonymity for nodes within a peer-to-peer network. To establish a mixing group that offers forward security, we employ the challenge-response model, forming a one-time chat room. This room utilizes a hierarchical key tree structure, generated through a key derivation primitive, wherein distinct branches serve specific purposes. This approach enables nodes in the group to construct their individual key trees, preventing the tracing of mixing records in an open network environment. Additionally, DcMix incorporates a variation of the Abe-Ohkubo-Suzuki (AOS) ring signature to conceal identities from both group nodes and online adversaries. DcMix achieves robust anonymity and transaction unforgeability, effectively countering known message attacks. Experimental results demonstrate that DcMix exhibits a computation overhead approximately 60% lower than CoinParty and CoinLayering with eight mixers. Furthermore, even with a high transaction volume of up to 1,900, DcMix’s computation overhead remains 25% lower than that of the aforementioned schemes.

The free fall of heavy bodies in a viscous fluid medium is a problem of interest to many engineering and scientific disciplines, including the study of unpowered flight and seed dispersal. The falling behaviour of coins and thin discs in particular has been categorized into one of four distinct modes; steady, fluttering, chaotic or tumbling, depending on the moment of inertia and Reynolds number. This paper investigates, through a carefully designed experiment, the falling dynamics of thin discs with central holes. The effects of the central hole on the disc’s motion is characterized for a range of Reynolds number, moments of inertia and inner to outer diameter ratio. By increasing this ratio, that is, the hole size, the disc is found to transition from tumbling to chaotic then fluttering at values of the moment of inertia not predicted by the falling modes of whole discs. This transition from tumbling to fluttering with increased hole size is viewed as a stabilization process. Flow visualization of the wake behind annular discs shows the presence of a vortex ring at the disc’s outer edge, as in the case of whole discs, and an additional counter-rotating vortex ring at the disc’s inner edge. The inner vortex ring is responsible for stabilizing the disc’s falling motion. These findings have significant implications on the development of design principles for engineered robotic systems in free flight, and may shed light on the stability of gliding animals.

Efficiency of coin manufacturing is often limited by the service life of the stamping dies, whose degradation by wear results in decreasing the quality of the produced coin engraving. The aim of this work is to explore the ability of the combined application of experimental characterization and numerical simulation of the material elastoplastic forming response, friction effects, and die material wear rate as a tool to contribute to the coin design in order to ultimately increase the number of coins that can be die forged before the use of a worn die compromises the desired quality of the final product. The following aspects have been particularly addressed in this study. First, the influence of two design parameters related with the quality of the coins, i.e., die displacement and depth of engraving, is quantified determining that the die displacement is the most preponderant since the stamping force needed in this process is higher compared with that obtained by varying the depth of engraving. In addition, it is found that the curvature of the coin relief determines the local stress distribution, in some cases even at the opposite die, resulting in a heterogeneous wear evolution. A complementary wear test reveals that, for the involved range of curvatures, the wear mechanism may shift from dominated by plowing/cutting to dominated by fatigue. It is concluded that the numerical simulation allows considering efficiency of the coining process already at the stage of the aesthetic design of a coin.

Attosecond X-ray pulses are short enough to capture snapshots of molecules undergoing nonadiabatic electron and nuclear dynamics at conical intersections (CoIns). We show that a stimulated Raman probe induced by a combination of an attosecond and a femtosecond pulse has a unique temporal and spectral resolution for probing the nonadiabatic dynamics and detecting the ultrafast (∼4.5 fs) passage through a CoIn. This is demonstrated by a multiconfigurational self-consistent-field study of the dynamics and spectroscopy of the furan ring-opening reaction. Trajectories generated by surface hopping simulations were used to predict Attosecond Stimulated X-ray Raman Spectroscopy signals at reactant and product structures as well as representative snapshots along the conical intersection seam. The signals are highly sensitive to the changes in nonadiabatically coupled electronic structure and geometry.

The two subjects in the title are related via the specialization of symmetric polynomials at roots of unity. Let \\(f(z_1,\\ldots,z_n)\\in\\mathbb{Z}[z_1,\\ldots,z_n]\\) be a symmetric polynomial with integer coefficients and let \\(\\omega\\) be a primitive \\(d\\)th root of unity. If \\(d|n\\) or \\(d|(n-1)\\) then we have \\(f(1,\\ldots,\\omega^{n-1})\\in\\mathbb{Z}\\). If \\(d|n\\) then of course we have \\(f(\\omega,\\ldots,\\omega^n)=f(1,\\ldots,\\omega^{n-1})\\in\\mathbb{Z}\\), but when \\(d|(n+1)\\) we also have \\(f(\\omega,\\ldots,\\omega^n)\\in\\mathbb{Z}\\). We investigate these three families of integers in the case \\(f=h_k^{(b)}\\), where \\(h_k^{(b)}\\) is the coefficient of \\(t^k\\) in the generating function \\(\\prod_{i=1}^n (1+z_it+\\cdots+(z_it)^{b-1})\\). These polynomials were previously considered by several authors. They interpolate between the elementary symmetric polynomials (\\(b\\)=2) and the complete homogeneous symmetric polynomials (\\(b\\to\\infty\\)). When \\(\\gcd(b,d)=1\\) with \\(d|n\\) or \\(d|(n-1)\\) we find that the integers \\(h_k^{(b)}=(1,\\omega,\\ldots,\\omega^{n-1})\\) are related to cyclic sieving of multisets with multiplicities bounded above by \\(b\\), generalizing the well know cyclic sieving results for sets (\\(b=2\\)) and multisets (\\(b\\to \\infty\\)). When \\(\\gcd(b,d)=1\\) and \\(d|(n+1)\\) we find that the integers \\(h_k^{(b)}(\\omega,\\omega^2,\\ldots,\\omega^n)\\) are related to the Frobenius coin problem with two coins. The case \\(\\gcd(b,d)\\neq 1\\) is more complicated. At the end of the paper we combine these results with the expansion of \\(h_k^{(b)}\\) in various bases of the ring of symmetric polynomials.

By allowing users to obscure their transactions via including \"mixins\" (chaff coins), ring signature schemes have been widely used to protect a sender's identity of a transaction in privacy-preserving blockchain systems, like Monero and Bytecoin. However, recent works point out that the existing ring signature scheme is vulnerable to the \"chain-reaction\" analysis (i.e., the spent coin in a given ring signature can be deduced through elimination). Especially, when the diversity of mixins is low, the spent coin will have a high risk to be detected. To overcome the weakness, the ring signature should be consisted of a set of mixins with high diversity and produce observations having \"similar\" distributions for any two coins. In this paper, we propose a notion, namely \\(\\epsilon\\)-coin-indistinguishability (\\(\\epsilon\\)-CI), to formally define the \"similar\" distribution guaranteed through a differential privacy scheme. Then, we formally define the CI-aware mixins selection problem with disjoint-superset constraint (CIA-MS-DS), which aims to find a mixin set that has maximal diversity and satisfies the constraints of \\(\\epsilon\\)-CI and the budget. In CIA-MS-DS, each ring signature is either disjoint with or the superset of its preceding ring signatures. We prove that CIA-MS-DS is NP-hard and thus intractable. To solve the CIA-MS-DS problem, we propose two approximation algorithms, namely the Progressive Algorithm and the Game Theoretic Algorithm, with theoretic guarantees. Through extensive experiments on both real data sets and synthetic data sets, we demonstrate the efficiency and the effectiveness of our approaches.

This paper discusses the Chionite dynasty, which ruled in Chach from the middle of the fourth to the beginning of the seventh century, and their coins. Careful study of their coins has allowed us to read the names of the Chionite rulers of Chach and to establish their line of succession. Coins show that the Chionites used an East Iranian language and were probably one of the East Iranian ethnic groups.

Ancient Greek literature, Athenian civic ideology, and modern classical scholarship have all worked together to reinforce the idea that there were three neatly defined status groups in classical Athens--citizens, slaves, and resident foreigners. But this book--the first comprehensive account of status in ancient democratic Athens--clearly lays out the evidence for a much broader and more complex spectrum of statuses, one that has important implications for understanding Greek social and cultural history. By revealing a social and legal reality otherwise masked by Athenian ideology, Deborah Kamen illuminates the complexity of Athenian social structure, uncovers tensions between democratic ideology and practice, and contributes to larger questions about the relationship between citizenship and democracy. Each chapter is devoted to one of ten distinct status groups in classical Athens (451/0-323 BCE): chattel slaves, privileged chattel slaves, conditionally freed slaves, resident foreigners (metics), privileged metics, bastards, disenfranchised citizens, naturalized citizens, female citizens, and male citizens. Examining a wide range of literary, epigraphic, and legal evidence, as well as factors not generally considered together, such as property ownership, corporal inviolability, and religious rights, the book demonstrates the important legal and social distinctions that were drawn between various groups of individuals in Athens. At the same time, it reveals that the boundaries between these groups were less fixed and more permeable than Athenians themselves acknowledged. The book concludes by trying to explain why ancient Greek literature maintains the fiction of three status groups despite a far more complex reality.