Endogenous circatidal rhythm in the Manila clam Ruditapes philippinarum (Bivalvia: Veneridae)

Manila clams, Ruditapes philippinarum, removed from their natural environment and maintained for 9 weeks in continuously immersed conditions exhibited a clear endogenous circatidal rhythm in oxygen consumption. The clams exhibited a semidiurnal rhythmicity in oxygen consumption after showing a diurnal pattern in the first few days (5 to 7 d) of the experiment. The results of the present study indicate that activity rhythms of clams are controlled not only by exogenous factors, but also by an endogenous circatidal periodicity

Modulated structures in electroconvection in nematic liquid crystals

Motivated by experiments in electroconvection in nematic liquid crystals with homeotropic alignment we study the coupled amplitude equations describing the formation of a stationary roll pattern in the presence of a weakly-damped mode that breaks isotropy. The equations can be generalized to describe the planarly aligned case if the orienting effect of the boundaries is small, which can be achieved by a destabilizing magnetic field. The slow mode represents the in-plane director at the center of the cell. The simplest uniform states are normal rolls which may undergo a pitchfork bifurcation to abnormal rolls with a misaligned in-plane director.We present a new class of defect-free solutions with spatial modulations perpendicular to the rolls. In a parameter range where the zig-zag instability is not relevant these solutions are stable attractors, as observed in experiments. We also present two-dimensionally modulated states with and without defects which result from the destabilization of the one-dimensionally modulated structures. Finally, for no (or very small) damping, and away from the rotationally symmetric case, we find static chevrons made up of a periodic arrangement of defect chains (or bands of defects) separating homogeneous regions of oblique rolls with very small amplitude. These states may provide a model for a class of poorly understood stationary structures observed in various highly-conducting materials ("prechevrons" or "broad domains").Comment: 13 pages, 13 figure

Construction of the Hill48 and Yld89 for Auto-body Steel Sheets considering the Strain Rate

This paper deals with the anisotropic material properties and the initial yield locus considering the strain rate. Uni-axial tensile tests are performed with variation of the strain rate in order to obtain flow stress curves and the tensile properties. The R-values have been measured with a high speed camera by analyzing the deformation history during the tensile test. Anisotropy of auto-body steel sheets have been described by using Hill48 and Yld89 (Barlat89) yield functions according to the strain rate ranged from 0.001/sec to 100/sec. Hill48 and Yld89 yield loci of auto-body steel sheets at various strain rates have been constructed in order to visualize the initial yield state. The performance of two yield criteria is evaluated by comparing yield loci constructed in the principal stress plane. The initial yield locus becomes different from the static one when the strain rate is considered to describe the anisotropy of the steel sheets

Failure Elongation of Steel Sheets for an Autobody at the High Strain Rate

This paper presents the dynamic failure elongation of conventional mild steels and advanced high strength steel sheets such as TRIP and DP steels. The failure elongation has been obtained from the high speed tensile testing machine with various strain rates ranged from 0.003/s to 200/s. The experimental result demonstrates that the tensile elongation does not simply decrease as the strain rate increases, but it decreases from the quasi-static state to the strain rate of 0.1 or 1/s and increases again up to the strain rate of 100/s. Furthermore, some high strength steels have the tendency that the tensile elongation increases as the strain rate increases. This tendency has varieties depending on the microstructure and forming history of sheet metal. Moreover, the localized strain rate hardening in the necking region induces the increase of elongation. This phenomenon is very important not only in sheet metal forming but also in the crashworthiness evaluation to predict the fracture of sheet metal members

Fluid Annotation: A Human-Machine Collaboration Interface for Full Image Annotation

We introduce Fluid Annotation, an intuitive human-machine collaboration interface for annotating the class label and outline of every object and background region in an image. Fluid annotation is based on three principles: (I) Strong Machine-Learning aid. We start from the output of a strong neural network model, which the annotator can edit by correcting the labels of existing regions, adding new regions to cover missing objects, and removing incorrect regions. The edit operations are also assisted by the model. (II) Full image annotation in a single pass. As opposed to performing a series of small annotation tasks in isolation, we propose a unified interface for full image annotation in a single pass. (III) Empower the annotator. We empower the annotator to choose what to annotate and in which order. This enables concentrating on what the machine does not already know, i.e. putting human effort only on the errors it made. This helps using the annotation budget effectively. Through extensive experiments on the COCO+Stuff dataset, we demonstrate that Fluid Annotation leads to accurate annotations very efficiently, taking three times less annotation time than the popular LabelMe interface.Comment: ACM MultiMedia 2018. Live demo is available at fluidann.appspot.co

Therapeutic embolization of the dural arteriovenous malformation involving the jugular bulb.

Pulsatile tinnitus is a rarely occurring symptom of vascular origin. Most frequently, the symptoms are due to an arteriovenous malformation, to a tumor of the jugular glomus or to a local arterial stenosis. A 39-yr-old Korean male suffering from pulsatile tinnitus of the left ear was diagnosed to have dural arteriovenous malformation of the jugular bulb. Magnetic resonance imaging and angiography revealed a high-velocity vascular lesion encroaching the internal jugular vein and sigmoid sinuses. Digital subtraction angiography demonstrated a dural arteriovenous malformation involving the jugular bulb. The arterial supply was from the neuromeningeal branch of the left ascending pharyngeal artery and inferior tympanic artery. Stenosis of the left jugular vein caused retrograde venous drainage through the contralateral transverse sinus. Superselective embolization of these feeding arteries was successfully performed using 25% mixture of N-butylcyanoacrylate and lipiodol. In postembolization period, his complaints of pulsatile tinnitus and buzzing noise behind his left ear disappeared

Complements of hypersurfaces, variation maps and minimal models of arrangements

We prove the minimality of the CW-complex structure for complements of hyperplane arrangements in $\mathbb C^n$ by using the theory of Lefschetz pencils and results on the variation maps within a pencil of hyperplanes. This also provides a method to compute the Betti numbers of complements of arrangements via global polar invariants