Do Addicts Behave Rationally?

Addicts, Rational Behavior

A generalization of Margolus-Levitin bound

The Margolus-Levitin lower bound on minimal time required for a state to be transformed into an orthogonal state is generalized. It is shown that for some initial states new bound is stronger than the Margolus-Levitin one.Comment: 6 pages, no figures; some comments added; final version accepted for publication in Phys. Rev.

The connection between metallicity and metal-line kinematics in (sub-)damped Lyman-alpha systems

A correlation between the metallicity, [M/H], and rest-frame MgII equivalent width, EW, is found from 49 DLAs and strong sub-DLAs drawn from the literature over the redshift range 0.2<z_abs<2.6. The correlation is significant at 4.2 sigma and improves to 4.7 sigma when the mild evolution of [M/H] with redshift is taken into account. Even when including only the 26 DLAs (i.e. excluding sub-DLAs) which have Zn metallicities and EW>0.7A, the correlation remains at >3 sigma significance. Since the MgII2796 transition is predominantly saturated in DLAs (which always have EW greater than 0.3A), EW is far more sensitive to the kinematic spread of the metal velocity components across the absorption profile than it is to [M/H]. Thus, the observed [M/H]--EW correlation points to a strong link between the absorber metallicity and the mechanism for producing and dispersing the velocity components. We also note that approximately half of the 13 known molecular hydrogen absorbers have very high EW and very broad velocity structures which show characteristics usually associated with outflows. Follow-up ultraviolet- and blue-sensitive high-resolution spectra of high-EW systems, initially identified in low-resolution spectra, may therefore yield a large number of new H_2 discoveries.Comment: 9 pages, 2 figures (3 EPS files). Accepted by MNRA

Analysis of modern methods of assessing the quality of sand foundry moulds

Currently offered devices for the hardness measuring or indices of the mould strength, are presented in the hereby paper. The presented results allow to compare approximately the indications of individual devices of different types.The description of the author’s own microprocessor tester for the quality assessment of the sand foundry moulds, is shown. On the bases of the measurements results it is possible, to evaluate indirectly, the mould apparent density in the selected points, as well as several other properties

The late Roman harbor temple of Berenike. Results of the 2010 season of excavations

Excavations in 2010 in the southwestern harbor at Berenike documented two distinct structures. One built of white gypsum/anhydrite ashlars was the earlier of the two. The later one, with walls composed mainly of extinct coral heads, but incorporating portions of the earlier ashlar structure, lay immediately southeast of the former. The later edifice, and the focus of this article, dated to the 4th and 5th centuries AD and clearly had a religious function. Excavations documented two major phases of this shrine and suggested that multiple creeds were venerated here, including one perhaps of South Arabian origin. Along with numerous cult objects made of metal, stone, terracotta, ostrich eggs and cowry shells there was ample floral and faunal evidence for offerings made or consumed by devotees.Iwona Zyc

Inhomogeneity of donor doping in SrTiO3 substrates studied by fluorescence-lifetime imaging microscopy

Fluorescence-lifetime imaging microscopy (FLIM) was applied to investigate the donor distribution in SrTiO3 single crystals. On the surfaces of Nb- and La-doped SrTiO3, structures with different fluorescence intensities and lifetimes were found that could be related to different concentrations of Ti3+. Furthermore, the inhomogeneous distribution of donors caused a non-uniform conductivity of the surface, which complicates the production of potential electronic devices by the deposition of oxide thin films on top of doped single crystals. Hence, we propose FLIM as a convenient technique (length scale: 1 $\mu$m) for characterizing the quality of doped oxide surfaces, which could help to identify appropriate substrate materials

The “Square Feature” in the harbor: Excavations in Berenike 2010–2011

The Berenike Project team explored, as one of a number of objectives, a square feature situated on an island or promontory in the southwestern harbor bay of the Berenike port, directly to the northwest of the “Lotus Temple”. The report is a preliminary assessment of the results of excavations carried out in 2010 and 2011, which uncovered the inside of the structure as well as a continuous surface of melted gypsum anhydrite around it that was proved to be at least in part a tumble of large wall ashlars. A provisional dating of the remains suggests an early Roman origin for the structure, which may have been a sanctuary. The findings indicate that it was already abandoned in the 4th–5th centuries when the neighboring “Lotus Temple”, uncovered concurrently by the Polish–American team, was at its peak. Finds included an inscribed altar dedicated to Domitian(?), discovered among the tumble of a stone basin and unidentified installation, and some remains of bronze statuary, oil lamps, glass beads and other finds.Iwona Zyc

Dynamic Data Structures for Parameterized String Problems

We revisit classic string problems considered in the area of parameterized complexity, and study them through the lens of dynamic data structures. That is, instead of asking for a static algorithm that solves the given instance efficiently, our goal is to design a data structure that efficiently maintains a solution, or reports a lack thereof, upon updates in the instance. We first consider the Closest String problem, for which we design randomized dynamic data structures with amortized update times $d^{\mathcal{O}(d)}$ and $|\Sigma|^{\mathcal{O}(d)}$, respectively, where $\Sigma$ is the alphabet and $d$ is the assumed bound on the maximum distance. These are obtained by combining known static approaches to Closest String with color-coding. Next, we note that from a result of Frandsen et al.~[J. ACM'97] one can easily infer a meta-theorem that provides dynamic data structures for parameterized string problems with worst-case update time of the form $\mathcal{O}(\log \log n)$, where $k$ is the parameter in question and $n$ is the length of the string. We showcase the utility of this meta-theorem by giving such data structures for problems Disjoint Factors and Edit Distance. We also give explicit data structures for these problems, with worst-case update times $\mathcal{O}(k2^{k}\log \log n)$ and $\mathcal{O}(k^2\log \log n)$, respectively. Finally, we discuss how a lower bound methodology introduced by Amarilli et al.~[ICALP'21] can be used to show that obtaining update time $\mathcal{O}(f(k))$ for Disjoint Factors and Edit Distance is unlikely already for a constant value of the parameter $k$.Comment: 28 page