Arc Pattern Research Articles

A comparative evaluation between dermatoglyphic patterns and different terminal planes in primary dentition.

BackgroundTo assess the correlation between different dermatoglyphic patterns with the terminal planes in deciduous dentition.Material and Methods300 children who are 3-6 years old with complete primary dentition were recruited and the pattern of molar terminal plane was recorded in the proforma. Finger prints of the distal phalanges of these subjects were recorded using ink and roller method and were analysed for the finger print pattern by a forensic specialist. The pattern were classified based on classification given by Galton. The finger ridge counts were also measured.ResultsUlnar loop pattern was the most predominant dermatoglyphic pattern. Absence of arch pattern in ring and little fingers of left hand and higher ridge count in left little finger when compared to the right hand were related to Mesial step. Presence of whorl pattern in both right and left middle finger and higher total finger ridge count in left hand when compared to the right hand were related to distal step. Flush terminal plane was related to absence of arc pattern in ring finger of left hand.ConclusionsDermatoglyphics can be used as a non invasive analytical tool to predict the terminal plane in primary dentition. Key words:Dermatoglyphics, terminal planes, primary dentition.

Effect of Laser-arc Hybrid Welding Energy Parameters on Welding Stability

The high-speed camera was used to collect the droplet transfer pattern and arc pattern of the laser-arc hybrid welding process. Using the methods of image processing and mathematical statistics, the effects of different laser and arc power conditions on the welding stability were studied. The results show that the melting width depends on the welding current, the depth of penetration depends on the laser power, the droplet transition pattern, the actual filament spacing and the arc length determine the welding stability of the laser arc hybrid welding.

Correlation between Fermi arc and charge order resulting from the momentum-dependent self-energy correction in cuprates

We calculate momentum-dependent self-energies due to self-consistent spin and charge-density fluctuations within a single-band Hubbard model for hole-doped cuprates. We find that the dynamical density instability (mainly paramagnonlike spin fluctuations) arising from the van Hove singularity at the antinodal point produces strongly anisotropic mass renormalization, increasing from the nodal direction to the antinodal one. This gives rise to a coherent Fermi arc pattern in which although the self-energy dressed Green's function has poles at all Fermi momenta, the corresponding spectral weight decreases from the nodal to the antinodal direction. We study the feedback effects of the anisotropic self-energy and Fermi arc on the charge-density wave (CDW) instability by direct computations of charge susceptibility and the quasiparticle interference pattern. We find that that due to the loss of spectral weight at the antinodal points, the CDW nesting weakens, and the corresponding hot spot shifts from the antinodal region to the tip of the Fermi arc below the magnetic Brillouin zone. The results are in good agreement with experiments, reproducing the observed slow doping dependence of the CDW wave vector. Our investigation therefore provides a mechanism for the Fermi arc in cuprates, with various testable predictions such as a sharp, first-order-like phase transition of the CDW order on the higher-doping side.

The circumstellar envelope around the S-type AGB star W Aql. Effects of an eccentric binary orbit.

Recent observations at subarcsecond resolution, now possible also at submillimeter wavelengths, have shown intricate circumstellar structures around asymptotic giant branch (AGB) stars, mostly attributed to binary interaction. The results presented here are part of a larger project aimed at investigating the effects of a binary companion on the morphology of circumstellar envelopes (CSEs) of AGB stars. AGB stars are characterized by intense stellar winds that build CSEs around the stars. Here, the CO(J = 3→2) emission from the CSE of the binary S-type AGB star W Aql has been observed at subarcsecond resolution using ALMA. The aim of this paper is to investigate the wind properties of the AGB star and to analyse how the known companion has shaped the CSE. The average mass-loss rate during the creation of the detected CSE is estimated through modelling, using the ALMA brightness distribution and previously published single-dish measurements as observational constraints. The ALMA observations are presented and compared to the results from a 3D smoothed particle hydrodynamics (SPH) binary interaction model with the same properties as the W Aql system and with two different orbital eccentricities. Three-dimensional radiative transfer modelling is performed and the response of the interferometer is modelled and discussed. The estimated average mass-loss rate of W Aql is Ṁ = 3.0×10-6 M⊙ yr-1 and agrees with previous results based on single-dish CO line emission observations. The size of the emitting region is consistent with photodissociation models. The inner 10″ of the CSE is asymmetric with arc-like structures at separations of 2-3″ scattered across the denser sections. Further out, weaker spiral structures at greater separations are found, but this is at the limit of the sensitivity and field of view of the ALMA observations. The CO(J = 3→2) emission is dominated by a smooth component overlayed with two weak arc patterns with different separations. The larger pattern is predicted by the binary interaction model with separations of ~10″ and therefore likely due to the known companion. It is consistent with a binary orbit with low eccentricity. The smaller separation pattern is asymmetric and coincides with the dust distribution, but the separation timescale (200 yrs) is not consistent with any known process of the system. The separation of the known companions of the system is large enough to not have a very strong effect on the circumstellar morphology. The density contrast across the envelope of a binary with an even larger separation will not be easily detectable, even with ALMA, unless the orbit is strongly asymmetric or the AGB star has a much larger mass-loss rate.

Lead isotope evolution across the Neoproterozoic boundary between craton and juvenile crust, Bayuda Desert, Sudan

Metaigneous mafic and ultramafic rocks from the juvenile Neoproterozoic Arabian Nubian Shield (ANS) and the Proterozoic, reworked Saharan Metacraton (SMC) have been analysed for major- and trace elements and Sr, Nd, and Pb isotopes. Most of the rocks are amphibolites metamorphosed at amphibolite facies conditions, some with relicts of a granulite facies stage. The other rocks are metapyroxenites, metagabbros, and some ultramafic rocks. Trace element compositions of the metabasaltic (dominantly tholeiitic) rocks resemble the patterns of island arcs and primitive lavas from continental arcs. Variable Sr and Nd isotope ratios indicate depleted mantle dominance for most of the samples. 207Pb/204Pb signatures distinguish between the influence of high 207Pb/204Pb old SMC crust and depleted mantle signatures of the juvenile ANS crust. The Pb isotope signatures for most metabasaltic rocks, metapyroxenites and metagabbros from SMC indicate an autochthonous formation. The interpretation of the new data together with published evidence from mafic xenoliths on SMC and ophiolite from ANS allows an extrapolation of mantle evolution in time. There are two lines of evolution in the regional mantle, one, which incorporates potential upper crust material during Neoproterozoic, and a second one with a depleted mantle signature since pre-Neoproterozoic that still is present in the Red Sea and Gulf of Aden spreading centres.

From Nodal Chain Semimetal to Weyl Semimetal in HfC.

Based on first-principles calculations and effective model analysis, we propose that the WC-type HfC, in the absence of spin-orbit coupling (SOC), can host a three-dimensional nodal chain semimetal state. Distinguished from the previous material IrF_{4} [T. Bzdusek etal., Nature 538, 75 (2016)], the nodal chain here is protected by mirror reflection symmetries of a simple space group, while in IrF_{4} the nonsymmorphic space group with a glide plane is a necessity. Moreover, in the presence of SOC, the nodal chain in WC-type HfC evolves into Weyl points. In the Brillouin zone, a total of 30 pairs of Weyl points in three types are obtained through the first-principles calculations. Besides, the surface states and the pattern of the surface Fermi arcs connecting these Weyl points are studied, which may be measured by future experiments.

Textured SnSe micro-sheets: One-pot facile synthesis and comprehensive understanding on the growth mechanism

Preferential aligned SnSe micro-sheets were successfully synthesized via a surfactant-free hydrothermal synthesis route. The Lotgering factor F and the intensity ratio of (400) to (111) for SnSe Micro-sheets prepared by the optimized process is 0.64, 9.85, respectively, which verify the obvious textured characteristic of micro-sheets. The micro-sheets with uniform composition are polycrystallines with an orthorhombic crystal structure, show the preferential aligned morphology assembled by a great deal of nano-particles according to observation and analysis from the electron diffraction pattern, the lattice fringe, the Energy-dispersive spectroscopy and the transmission electron microscopy (TEM) images. Through deep observation from high-resolution transmission electron microscopy, an arc pattern verifies the textured characteristic of the SnSe sheet. The preferential aligned growth mechanism can be understood by researching effect of reaction temperature, alkali concentration on phase, preferred orientation and morphology. A proper temperature can control textured degree via adjusting effective diffusion, rotation of nano-crystal and fluid movement. Increasing alkali concentration enhances the surface adsorption stability of chalcogenides, and decreases new nucleation site in the (011) face, and helps the dis-matched nano-crystal re-dissolute, which results in formation of square-like textured micro-sheets. A proposed growth mechanism of textured SnSe micro-sheets with two growth models (the lateral growth model and the vertical growth model) is provided, and the two growth models control textured characteristic of micro-sheets, which can be adjusted by change of reaction temperature and alkali concentration.

The effect of meshing and comparing different turbulence models in predicting the topography of Bed and flow field in the 90 degree bend with moving Bed

Centrifugal force at the bend causes the terrain slope at water surface that increases water surface in outer arc and reduces in internal arc. This phenomenon creates adverse pressure gradient inside the arc of cross. As a result, a flow in the transverse direction within the cross is shaped that is called secondary flow. Secondary flow and its interaction with the inertia of the flow, which leads to create a spiral flow causes changes in the topography of the Bed. Understanding the topography of Bed in arcs is essential for specifying scour positions and sediments to determine the best location for the construction of hydraulic structures such as the groin, pond and rivers organizing management. Also in numerical models, one of the most important steps is meshing optimization to achieve the most accurate results and also the least time of analysis of model. Since investigating the numerical sediment transport has been very difficult and research in this area is little; In this study, the most optimal meshing in numerical model is investigated and then tried to be stimulated scouring in the channel bend 90°. For this purpose, the results of the topography of Bed within the arc of channel are obtained using the software FLOW3D and with different turbulence models and compared with experimental results. It should be noted that due to inability of software in the results in perpendicular sections and in direction of flow in the arc, neural network and genetic pattern was used for extracting numerical results in points matching laboratory results. Then flow field in arc is compared with experimental results. The results show the high ability of numerical model FLOW3D in simulating channel with moving Bed. The comparison of turbulence models indicates superiority of turbulence model of LES in investigating changes of Bed in arc channel to other turbulence models.

Laser Heating of 2-D Dusty Plasmas Using a Random Arc Pattern

A laser heating method for 2-D dusty plasmas is improved so that particle motion better resembles thermal motion in a liquid. Laser beams are rastered in a pattern of arcs with three randomly varying parameters: curvature, initial angle, and the speed of the laser footprint as it follows an arc. An experimental test is performed using particle tracking to generate power spectra of velocities. Peaks in these spectra indicate coherence in the particle motion, which is a discrepancy when compared with the stochastic nature of molecular motion in a liquid. We find that spectral peaks are diminished tenfold by rastering with random arcs as compared with a previously used pattern in which beams moved in straight lines at constant speeds.

On the orientation of palmar whorl patterns

The objective of the present work was to study the palmar whorl patterns for the inclusion them in the scope of dermatoglyphic signs along with the arc and loop patterns having a well apparent structural organization. For the first time in the history of domestic dermatoglyphic studies, we described the structure of palmar whorl patterns (based on the palmar prints obtained from 555 subjects) with respect to the surrounding tri-radii. Moreover, the role of their radiants in the formation of node orientation was considered. The analysis of the variants of palmar whorl patterns encountered in the study sample provided a basis for the elaboration of the rule for determining their orientation. Specifically, the orientation of the palmar whorl patterns can be found from the direction of the embracing radiants as in the loop or complex patterns.

Topological patterns in two-dimensional gel electrophoresis of DNA knots

Gel electrophoresis is a powerful experimental method to probe the topology of DNA and other biopolymers. Although there is a large body of experimental work that allows us to accurately separate different topoisomers of a molecule, a full theoretical understanding of these experiments has not yet been achieved. Here we show that the mobility of DNA knots depends crucially and subtly on the physical properties of the gel and, in particular, on the presence of dangling ends. The topological interactions between these and DNA molecules can be described in terms of an "entanglement number" and yield a nonmonotonic mobility at moderate fields. Consequently, in 2D electrophoresis, gel bands display a characteristic arc pattern; this turns into a straight line when the density of dangling ends vanishes. We also provide a novel framework to accurately predict the shape of such arcs as a function of molecule length and topological complexity, which may be used to inform future experiments.

Miura-Base Rigid Origami: Parametrizations of Curved-Crease Geometries

Curved-crease (CC) origami differs from prismatic, or straight-crease origami, in that the folded surface of the pattern is bent during the folding process. Limited studies on the mechanical performance of such geometries have been conducted, in part because of the difficulty in parametrizing and modeling the pattern geometry. This paper presents a new method for generating and parametrizing rigid-foldable, CC geometries from Miura-derivative prismatic base patterns. The two stages of the method, the ellipse creation stage and rigid subdivision stage, are first demonstrated on a Miura-base pattern to generate a CC Miura pattern. It is shown that a single additional parameter to that required for the straight-crease pattern is sufficient to completely define the CC variant. The process is then applied to tapered Miura, Arc, Arc-Miura, and piecewise patterns to generate CC variants of each. All parametrizations are validated by comparison with physical prototypes and compiled into a matlab Toolbox for subsequent work.

Visualization of arc and plasma flow patterns for advanced material processing

Results are presented for physical experiments that illustrate the possibilities and efficiency of visualization for studying the effect of operating conditions (backward-facing stepped forming nozzle, exit diameter of anode, mass flow, and composition of working gas) on plasma flows at low Reynolds numbers for advanced coating and powder processing. In particular, the shadow method, based on adaptive visualization transparency, is used for imaging electric arc and plasma jet flow patterns for different operating conditions. Because of visualization, the optimal geometrical characteristics of the backward-facing stepped forming nozzle, mass flow rate of the working gas, and its composition were found. These provide: (1) the absence of micro-shunting of the arc inside the backward-facing stepped nozzle for a transfer arc and twin arcs; and (2) compared to transient and turbulent jets, a higher density for the heat flux from a quasi-laminar flow to the surface of a flat substrate and the powder material to be treated, for nontransfer arc DC (direct current) torches and DC–RF (direct current and radio frequency) hybrid plasma flow system.

Immediate-early gene expression in structures outside the basal ganglia is associated to l-DOPA-induced dyskinesia

Long-term l-3,4-dihydroxyphenylalanine (l-DOPA) treatment in Parkinson's disease (PD) leads to l-DOPA-induced dyskinesia (LID), a condition thought to primarily involve the dopamine D1 receptor-expressing striatal medium spiny neurons. Activation of the D1 receptor results in increased expression of several molecular markers, in particular the members of the immediate-early gene (IEG) family, a class of genes rapidly transcribed in response to an external stimulus. However, several dopaminoceptive structures in the brain that are likely to be affected by the exogenously produced DA have received little attention although they might play a key role in mediating those l-DOPA-induced abnormal behaviours. ΔFosB, ARC, FRA2 and Zif268 IEGs expression patterns were thus characterised, using unbiased stereological methods, in the whole brain of dyskinetic and non-dyskinetic rats to identify brain nuclei displaying a transcriptional response specifically related to LID. Within the basal ganglia, the striatum and the substantia nigra pars reticulata showed an increased expression of all four IEGs in dyskinetic compared to non-dyskinetic rats. Outside the basal ganglia, there was a striking increased expression of the four IEGs in the motor cortex, the bed nucleus of the stria terminalis, the dorsal hippocampus, the pontine nuclei, the cuneiform nucleus and the pedunculopontine nuclei. Moreover, the zona incerta and the lateral habenula displayed an overexpression of ΔFosB, ARC and Zif268. Among these structures, the IEG expression in the striatum, the bed nucleus of the stria terminalis, the lateral habenula, the pontine nuclei and the cuneiform nucleus correlate with LID severity. These results illustrate a global transcriptional response to a dyskinetic state in the whole brain suggesting the possible involvement of these structures in LID.

WIDE BINARY EFFECTS ON ASYMMETRIES IN ASYMPTOTIC GIANT BRANCH CIRCUMSTELLAR ENVELOPES

Observations of increasingly higher spatial resolution reveal the existence of asymmetries in the circumstellar envelopes of a small fraction of asymptotic giant branch (AGB) stars. Although there is no general consensus for their origin, a binary companion star may be responsible. Within this framework, we investigate the gravitational effects associated with a sufficiently wide binary system, where Roche lobe overflow is unimportant, on the outflowing envelopes of AGB stars using three dimensional hydrodynamic simulations. The effects due to individual binary components are separately studied, enabling investigation of the stellar and circumstellar characteristics in detail. The reflex motion of the AGB star alters the wind velocity distribution, thereby, determining the overall shape of the outflowing envelope. On the other hand, the interaction of the companion with the envelope produces a gravitational wake, which exhibits a vertically thinner shape. The two patterns overlap and form clumpy structures. To illustrate the diversity of shapes, we present the numerical results as a function of inclination angle. Not only is spiral structure produced by the binary interaction, but arc patterns are also found that represent the former structure when viewed at different inclinations. The arcs reveal a systematic shift of their centers of curvature for cases when the orbital speed of the AGB star is comparable to its wind speed. They take on the shape of a peanut for inclinations nearly edge-on. In the limit of slow orbital motion of the AGB star relative to the wind speed, the arc pattern becomes nearly spherically symmetric. We find that the aspect ratio of the overall oblate shape of the pattern is an important diagnostic probe of the binary as it can be used to constrain the orbital velocity of the AGB star, and moreover the binary mass ratio.

Heat Transfer and Frictional Characteristics of Rectangular Channel Air Heater Duct Having Protrusion as Roughness Elements

An experimental investigation has been carried out to see the effect of roughness element on heat transfer and friction factor on the absorber plate of the solar air heater. The roughness provided is in the form of protrusions which are arranged in an arc pattern. This paper presents an investigation to study the effect of protruded geometry on heat transfer coefficient and friction factor in an artificially roughened solar air heater duct. The protrusions forming an arc having an arc angle (α) of 60° which is mounted on the test section of duct to create turbulent flow through the test section. Measurements are carried out for rectangular duct of having aspect ratio (W/H) of 11 and Reynolds number (Re) ranges from 3,500 to 18,000. The results obtained for various relative roughness pitch (P/e) has been compared with smooth one.

Unusual Proximal Dislocation without Fracture: A Case Report

Carpal instability includes a broad spectrum of osseous and ligamentous injuries which have been subclassified into greater and lesser arc injuries, in addition to combinations of both (Mayfield et al. J Hand Surg [Am] 5:226-241, 1980; Yaeger et al. Skeletal Radiol 13(2):120-30, 1985). The injuries typically occur from a fall on the outstretched hand with the wrist in ulnar deviation, hyperextension, and intercarpal supination (Yaeger et al. Skeletal Radiol 13(2):120-30, 1985). The force classically propagates from the radial to the ulnar side of the wrist resulting in a fracture (greater arc) or dislocation (lesser arc) pattern with the extent of the injury occurring in an orderly pattern depending upon the degree of hyperextension and the duration and magnitude of the force (Mayfield et al. J Hand Surg [Am] 5:226-241, 1980; Yaeger et al. Skeletal Radiol 13(2):120-30, 1985). Multiple variations occur, including transradial styloid fractures as well as fractures through carpal bones surrounding the lunate (Mayfield et al. J Hand Surg [Am] 5:226-241, 1980; Yaeger et al. Skeletal Radiol 13(2):120-30, 1985; Kozin SH. J Am Acad Orthop Surg 6 (2): 114-20, 1998. Although carpal dislocations have been noted for many years, the mechanisms and classification have only been recently clarified. We report a case of a complex dislocation involving the entire proximal carpal row without an associated fracture. While this type of complex carpal dislocation has been previously described, to our knowledge, it has never been reported without a fracture of the forearm, wrist, or hand.

Orchestrated experience-driven Arc responses are disrupted in a mouse model of Alzheimer's disease

Experience-induced expression of immediate-early gene Arc/Arg3.1 is known to play a pivotal role in the consolidation of memory. Here we use in-vivo longitudinal multiphoton imaging to show orchestrated activity-dependent expression of Arc in the mouse extrastriate visual cortex in response to a structured visual stimulation. In wild-type mice, the amplitude of the Arc response in individual neurons strongly predicts the probability of reactivation by a subsequent presentation of the same stimulus. In a mouse model of Alzheimer’s disease, this association is markedly disrupted in the cortex specifically near senile plaques. Neurons in the vicinity of plaques are less likely to respond but, paradoxically, there is stronger response in those few neurons around plaques that do respond. To the extent that the orchestrated pattern of Arc expression reflects nervous system responses to, and physiological consolidation of, behavioral experience, the disruption in Arc patterns reveals plaque-associated interference with neural network integration.

Global network of slow solar wind

The streamer belt region surrounding the heliospheric current sheet (HCS) is generally treated as the primary or sole source of the slow solar wind. Synoptic maps of solar wind speed predicted by the Wang‐Sheeley‐Arge model during selected periods of solar cycle 23, however, show many areas of slow wind displaced from the streamer belt. These areas commonly have the form of an arc that is connected to the streamer belt at both ends. The arcs mark the boundaries between fields emanating from different coronal holes of the same polarity and thus trace the paths of belts of pseudostreamers, i.e., unipolar streamers that form over double arcades and lack current sheets. The arc pattern is consistent with the predicted topological mapping of the narrow open corridor or singular separator line that must connect the holes and, thus, consistent with the separatrix‐web model of the slow solar wind. Near solar maximum, pseudostreamer belts stray far from the HCS‐associated streamer belt and, together with it, form a global‐wide web of slow wind. Recognition of pseudostreamer belts as prominent sources of slow wind provides a new template for understanding solar wind stream structure, especially near solar maximum.

Dimensioning the Sine‐Generated Curve Meander Geometry1

Mecklenburg, Daniel E. and Anand D. Jayakaran, 2012. Dimensioning the Sine‐Generated Curve Meander Geometry. Journal of the American Water Resources Association (JAWRA) 48(3): 635‐642. DOI: 10.1111/j.1752‐1688.2012.00638.xAbstract: The sine‐generated curve (SGC) presented by Langbein and Leopold (1966) is widely acknowledged as an idealized description of river meander form. However, as originally presented, the SGC application to the field, laboratory, or models is not a trivial task. The SGC function simply provides the direction of the flow path as its rate of change continually varies from most gradual at the crossover to most rapid at the apex of bends. Although the commonly used dimensions of meander length, stream length per meander, sinuosity, and amplitude have been approximated previously, this technical note precisely defines these dimensions by solving the integrals of the sine and cosine of the SGC function. This is performed using integral representations of the Bessel and Struve functions for the zero order and their power‐series expansions. Higher precision offered by this technique will be of particular value to modeling and flume‐based studies where better conformity to the SGC is necessary. The note goes on to present two simple line and arc patterns optimally fit to the SGC as simplified yet more precise methods for practical design in river restoration schemes. Equations are presented defining the geometry of the arc and line pattern and relating meander length, amplitude, radius of curvature, and sinuosity.