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Multi-trace-element sea surface temperature coral reconstruction for the southern Mozambique Channel reveals teleconnections with the tropical Atlantic

Here we report seasonally resolved sea surface temperatures for the southern Mozambique Channel in the SW Indian Ocean based on multi-trace-element temperature proxy records preserved in two Porites sp. coral cores. Particularly, we assess the suitability of both separate and combined Sr∕Ca and Li∕Mg proxies for improved multielement SST reconstructions. Overall, geochemical records from Europa Island Porites sp. highlight the potential of Sr∕Ca and Li∕Mg ratios as high-resolution climate pro...

Personal verification based on multi-spectral finger texture lighting images

Finger texture (FT) images acquired from different spectral lighting sensors reveal various features. This inspires the idea of establishing a recognition model between FT features collected using two different spectral lighting forms to provide high recognition performance. This can be implemented by establishing an efficient feature extraction and effective classifier, which can be applied to different FT patterns. So, an effective feature extraction method called the surrounded patterns co...

Matchbox manifolds are foliated spaces with totally disconnected transversals. Two matchbox manifolds which are homeomorphic have return equivalent dynamics, so that invariants of return equivalence can be applied to distinguish nonhomeomorphic matchbox manifolds. In this work we study the problem of showing the converse implication: when does return equivalence imply homeomorphism? For the class of weak solenoidal matchbox manifolds, we show that if the base manifolds satisfy a strong form o...

Clark, Alex; Hurder, Steven; Lukina, Olga

Multimessenger observations of a flaring blazar coincident with high-energy neutrino IceCube-170922A

Previous detections of individual astrophysical sources of neutrinos are limited to the Sun and the supernova 1987A, whereas the origins of the diffuse flux of high-energy cosmic neutrinos remain unidentified. On 22 September 2017, we detected a high-energy neutrino, IceCube-170922A, with an energy of ~290 tera–electron volts. Its arrival direction was consistent with the location of a known γ-ray blazar, TXS 0506+056, observed to be in a flaring state. An extensive multiwavelength campaign f...

Aartsen, MG; Ackermann, M; Adams, J; Aguilar, JA; Ahlers, M... et al.

Mathematical models and simulated annealing algorithms for the robotic assembly line balancing problem

Purpose
Robots are used in assembly lines because of their higher flexibility and lower costs. The purpose of this paper is to develop mathematical models and simulated annealing algorithms to solve the robotic assembly line balancing (RALB-II) to minimize the cycle time.
Design/methodology/approach
Four mixed-integer linear programming models are developed and encoded in CPLEX solver to find optimal solutions for small-sized problem instances. Two simulated annealing algorithms, origina...

Correction of AI systems by linear discriminants: Probabilistic foundations

Artificial Intelligence (AI) systems sometimes make errors and will make errors in the future, from time to time. These errors are usually unexpected, and can lead to dramatic consequences. Intensive development of AI and its practical applications makes the problem of errors more important. Total re-engineering of the systems can create new errors and is not always possible due to the resources involved. The important challenge is to develop fast methods to correct errors without damaging ex...

Grechuk, B; Gorban, A; Golubkov, A; Mirkes, E; Tyukin, I

An analytical model for the flat punch indentation size effect

An analytical approximation for the indentation size effect (ISE) due to plane strain flat punch nanoindentation is derived. The flat punch ISE differs from that observed for self-similar (pointed) and spherical indenters in a number of ways: (1) the contact area does not change; (2) the contact pressure depends on two length scales not just one (the punch width and the indentation depth); (3) the profile of the punch is not differentially continuous, resulting in singular plastic strain grad...

Campbell, C. J.; Gill, S .P. A.

A model for the indentation size effect in polycrystalline alloys coupling intrinsic and extrinsic length scales

The measured hardness of a metal crystal depends on a variety of length scales. Microstructural features, such as grain size and precipitate spacing, determine the intrinsic material length scale. Extrinsic (test) length scales, such as the indentation depth, lead to the indentation size effect (ISE), whereby it is typically found that smaller is stronger. Nix and Gao [J. Mech. Phys. Solids46, 411 (1998)] developed a widely used model for interpreting the ISE based on forest hardening in sing...

Gill, Simon P. A.; Campbell, Christopher J.

SL_2-Tilings Do Not Exist in Higher Dimensions (mostly)

We define a family of generalizations of SL2-tilings to higher dimensions called
epsilon-SL2-tilings. We show that, in each dimension 3 or greater, epsilon-SL2-tilings exist only for
certain choices of epsilon. In the case that they exist, we show that they are essentially unique
and have a concrete description in terms of odd Fibonacci numbers.

Demonet, L; Plamondon, P-G; Rupel, D; Stella, S; Tumarkin, P

Multiple Sclerosis Identification by 14-Layer Convolutional Neural Network With Batch Normalization, Dropout, and Stochastic Pooling.

Aim: Multiple sclerosis is a severe brain and/or spinal cord disease. It may lead to a wide range of symptoms. Hence, the early diagnosis and treatment is quite important. Method: This study proposed a 14-layer convolutional neural network, combined with three advanced techniques: batch normalization, dropout, and stochastic pooling. The output of the stochastic pooling was obtained via sampling from a multinomial distribution formed from the activations of each pooling region. In addition, w...

Zebrafish Embryo Vessel Segmentation Using a Novel Dual ResU-Net model

Zebrafish embryo fluorescent vessel analysis, which aims to automatically investigate the pathogenesis of diseases, has attracted much attention in medical imaging. Zebrafish vessel segmentation is a fairly challenging task, which requires distinguishing foreground and background vessels from the 3D projection images. Recently, there has been a trend to introduce domain knowledge to deep learning algorithms for handling complex environment segmentation problems with accurate achievements. In ...

Multi-wavelength observations of the EUV variable metal-rich white dwarf GD 394

We present new Hubble Space Telescope (HST) ultraviolet and ground-based optical observations of the hot, metal-rich white dwarf GD 394. Extreme-ultraviolet (EUV) observations in 1992-1996 revealed a 1.15d periodicity with a 25 percent amplitude, hypothesised to be due to metals in a surface accretion spot. We obtained phase-resolved HST/Space Telescope Imaging Spectrograph (STIS) high-resolution far-ultraviolet (FUV) spectra of GD 394 that sample the entire period, along with a large body of...

Getting the strain under control: Trans-Varestraint tests for hot cracking susceptibility

A new method for conducting Trans-Varestraint tests for assessing hot cracking susceptibility is proposed. Experiments were carried out, to validate the new method, with an industrial scale rig using tungsten inert gas welding. The hot cracking susceptibility of API-5L X65 and EN3B steel was compared. The results indicated that, by using the new method, the strain applied to the welding bead and consequently to the solidification front was controlled in a repeatable and reliable way. The resu...

A note on (co)homologies of algebras from unpunctured surfaces

In a previous paper, the author computed the dimension of Hochschild cohomology groups of Jacobian algebras from (unpunctured) triangulated surfaces, and gave a geometric interpretation of those numbers in terms of the number of internal triangles, the number of vertices and the existence of certain kind of boundaries. The aim of this note is to compute the cyclic (co)homology and the Hochschild homology of the same family of algebras and to give an interpretation of those dimensions through ...

Valdivieso-Díaz, Yadira

On finite dimensional Jacobian algebras

We show that Jacobian algebras arising from every tagged triangulation of a
sphere with n-punctures, with n ≥ 5, are finite dimensional algebras. We consider also
a family of cyclically oriented quivers and we prove that, for any primitive potential,
the associated Jacobian algebra is finite dimensional.

Trepode, Sonia; Valdivieso-Díaz, Yadira

Jacobian algebras with periodic module category and exponential growth

Recently it was proven by Geiss, Labardini-Fragoso and Sh¨oer in [1] that every Jacobian
algebra associated to a triangulation of a closed surface S with a collection of marked points
M is tame and Ladkani proved in [2] these algebras are (weakly) symmetric. In this work we
show that for these algebras the Auslander-Reiten translation acts 2-periodically on objects.
Moreover, we show that excluding only the case of a sphere with 4 (or less) punctures, these
algebras are of exponential gr...

Valdivieso-Díaz, Yadira

Precise determination of heme binding affinity in proteins.

Accumulating evidence suggests a new role for cellular heme as a signalling molecule, in which interactions with target proteins are more transient than found with traditionally-defined hemoproteins. To study this role, a precise method is needed for determining the heme-binding affinity (or dissociation constant, Kd). Estimates of Kd are commonly made following a spectrophotometric titration of an apo-protein with hemin. An impediment to precise determination is, however, the challenge in di...

Leung, Galvin C.-H.; Fung, Simon S.-P.; Dovey, Nicholas R. B.; Raven, Emma L.; Hudson, Andrew J.

Equivariant Vector Bundles Over Quantum Projective Spaces

We construct equivariant vector bundles over quantum projective spaces using parabolic Verma modules over the quantum general linear group. Using an alternative realization of the quantized coordinate ring of the projective space as a subalgebra in the algebra of functions on the quantum group, we reformulate quantum vector bundles in terms of quantum symmetric pairs. We thus prove the complete reducibility of modules over the corresponding coideal stabilizer subalgebras, via the quantum Frob...

Mudrov, A. I.

Modeling for Life Estimation of HVDC Cable Insulation Based on Small-size Specimens

A quantitative numerical concept is presented for life estimation of large-size samples of cable insulation using experimental data from
thin films, which can potentially become an ancillary tool for designs, evaluations, and diagnostics of full-size insulating systems and their
manufacturing qualities.

Kinetic regimes in aggregating systems with spontaneous and collisional fragmentation

We analyze systems composed of clusters and interacting upon colliding---a collision between two clusters may lead to merging (an aggregation event) or fragmentation---and we also investigate the effect of additional, spontaneous fragmentation events. We consider closed systems in which the total mass remains constant and open systems driven by a source of small-mass clusters. In closed systems, the size distribution of aggregates approaches a steady state. For these systems the relaxation ti...

Bodrova, Anna S.; Stadnichuk, Vladimir; Krapivsky, P. L.; Schmidt, Jürgen; Brilliantov, Nikolai V.