lchneumonidae (Hymenoptera) new to Finland. V.

Eight lchneumonid species new to Finland are reported: Scambus eucosmidarum (Perkins), Mastrus pictipes (Gravenhorst), M. tenuicosta (Thomson), Endasys annulatus (Habermehl), Phygadeuon occisor Habermehl, Atractodes romani Jussila, Oresbius puncticollis (Thomson) and Aptesis albulatoria (Gravenhorst)

Unboundedness Problems for Languages of Vector Addition Systems

A vector addition system (VAS) with an initial and a final marking and transition labels induces a language. In part because the reachability problem in VAS remains far from being well-understood, it is difficult to devise decision procedures for such languages. This is especially true for checking properties that state the existence of infinitely many words of a particular shape. Informally, we call these unboundedness properties. We present a simple set of axioms for predicates that can express unboundedness properties. Our main result is that such a predicate is decidable for VAS languages as soon as it is decidable for regular languages. Among other results, this allows us to show decidability of (i) separability by bounded regular languages, (ii) unboundedness of occurring factors from a language K with mild conditions on K, and (iii) universality of the set of factors

Ion traps fabricated in a CMOS foundry

We demonstrate trapping in a surface-electrode ion trap fabricated in a 90-nm CMOS (complementary metal-oxide-semiconductor) foundry process utilizing the top metal layer of the process for the trap electrodes. The process includes doped active regions and metal interconnect layers, allowing for co-fabrication of standard CMOS circuitry as well as devices for optical control and measurement. With one of the interconnect layers defining a ground plane between the trap electrode layer and the p-type doped silicon substrate, ion loading is robust and trapping is stable. We measure a motional heating rate comparable to those seen in surface-electrode traps of similar size. This is the first demonstration of scalable quantum computing hardware, in any modality, utilizing a commercial CMOS process, and it opens the door to integration and co-fabrication of electronics and photonics for large-scale quantum processing in trapped-ion arrays.Comment: 4 pages, 3 figure

C and S induces changes in the electronic and geometric structure of Pd(533) and Pd(320)

We have performed ab initio electronic structure calculations of C and S adsorption on two vicinal surfaces of Pd with different terrace geometry and width. We find both adsorbates to induce a significant perturbation of the surface electronic and geometric structure of Pd(533) and Pd(320). In particular C adsorbed at the bridge site at the edge of a Pd chain in Pd(320) is found to penetrate the surface to form a sub-surface structure. The adsorption energies show almost linear dependence on the number of adsorbate-metal bonds, and lie in the ranges of 5.31eV to 8.58eV for C and 2.89eV to 5.40eV for S. A strong hybridization between adsorbate and surface electronic states causes a large splitting of the bands leading to a drastic decrease in the local densities of electronic states at the Fermi-level for Pd surface atoms neighboring the adsorbate which may poison catalytic activity of the surface. Comparison of the results for Pd(533) with those obtained earlier for Pd(211) suggests the local character of the impact of the adsorbate on the geometric and electronic structures of Pd surfaces.Comment: 14 pages 9 figs, Accepted J. Phys: Conden

Ehrenfeucht-Fraïssé goes elementarily automatic for structures of bounded degree

International audienceMany relational structures are automatically presentable, i.e. elements of the domain can be seen as words over a finite alphabet and equality and other atomic relations are represented with finite automata. The first-order theories over such structures are known to be primitive recursive, which is shown by the inductive construction of an automaton representing any relation definable in the first-order logic. We propose a general method based on Ehrenfeucht-Fraïssé games to give upper bounds on the size of these automata and on the time required to build them. We apply this method for two different automatic structures which have elementary decision procedures, Presburger Arithmetic and automatic structures of bounded degree. For the latter no upper bound on the size of the automata was known. We conclude that the very general and simple automata-based algorithm works well to decide the first-order theories over these structures

Ancient Egypt, the Ice Age, and Biblical Chronology

The history, archaeology, geography, and geology of ancient Egypt are examined with respect to the post-Flood Ice Age. It is shown that the Ice Age must have ended before the formation of the Nile Delta, and therefore well before the beginnings of Egyptian civilization and Abraham’s visit to Egypt. It is shown that more time for events between the Flood and Abraham is needed than the Masoretic timeline allows; the longer chronology of the Septuagint is therefore most likely correct

Model-Checking Counting Temporal Logics on Flat Structures

We study several extensions of linear-time and computation-tree temporal logics with quantifiers that allow for counting how often certain properties hold. For most of these extensions, the model-checking problem is undecidable, but we show that decidability can be recovered by considering flat Kripke structures where each state belongs to at most one simple loop. Most decision procedures are based on results on (flat) counter systems where counters are used to implement the evaluation of counting operators

Loading of a surface-electrode ion trap from a remote, precooled source

We demonstrate loading of ions into a surface-electrode trap (SET) from a remote, laser-cooled source of neutral atoms. We first cool and load $\sim$ $10^6$ neutral $^{88}$Sr atoms into a magneto-optical trap from an oven that has no line of sight with the SET. The cold atoms are then pushed with a resonant laser into the trap region where they are subsequently photoionized and trapped in an SET operated at a cryogenic temperature of 4.6 K. We present studies of the loading process and show that our technique achieves ion loading into a shallow (15 meV depth) trap at rates as high as 125 ions/s while drastically reducing the amount of metal deposition on the trap surface as compared with direct loading from a hot vapor. Furthermore, we note that due to multiple stages of isotopic filtering in our loading process, this technique has the potential for enhanced isotopic selectivity over other loading methods. Rapid loading from a clean, isotopically pure, and precooled source may enable scalable quantum information processing with trapped ions in large, low-depth surface trap arrays that are not amenable to loading from a hot atomic beam

Linear Propagation Properties for a 300 nm Film Height Silicon Nitride Photonic Integration Platform in the Optical Telecom C-band

[EN] In this paper we report on the characterization of the propagation loss, group index, dispersion, birefringence, and thermo-optic phase shift of Si 3 N 4 strip waveguides with guiding film height of 300 nm fabricated using low-preassure chemical vapour depositionThe authors acknowledge financial support through projects TEC2013-42332-P, TEC2015-69787-REDT PIC4TB, TEC2016-80385-P SINXPECT, TEC2014-54449-C3-1-R, GVA PROMETEO 2013/012, EC H2020-ICT-27-2015 CSA 687777 and IP 688519, FEDER UPVOV 10-3E-492 and 08- 3E-008. G.M. acknowledges BES-2014-068523. L.B. acknowledges PTA2015-11309-IBru-Orgiles, LA.; Mico-Cabanes, G.; Pastor Abellán, D.; Pérez-López, D.; Doménech, D.; Sanchez, AM.; Cirera, JM.... (2017). Linear Propagation Properties for a 300 nm Film Height Silicon Nitride Photonic Integration Platform in the Optical Telecom C-band. Optical Society of America (OSA). 1-3. https://doi.org/10.1364/IPRSN.2017.IW2A.6S13Krimmel, E. F., Hezel, R., Nohl, U., & Bohrer, R. (1991). 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