Effect of light polarization on plasma distribution and filament formation

We show that, for 200 fs light pulses at 790 nm, the formation of filaments is strongly affected by the laser light polarization . Filamentation does not exist for a pure circularly polarized light, propagating in vacuum before focusing in air, while there is no difference for focusing the light in air or vacuum for linearly polarized light.Comment: 4pages 2 figure

Automated Device to Enable Passive Pronation and Supination Activities of the Hand for Experimental Testing with Cadaveric Specimens: A Collaboration Between The University of New Mexico and New Mexico Institute of Mining and Technology

In cadaveric research, reproducing physiological conditions under which the specimens would be loaded in vivo is essential to achieve clinical applicability. This is a collaborative study bringing together engineers from The University of New Mexico and New Mexico Institute of Mining and Technology. We describe development of an automated device to enable passive pronation and supination of the hand (rotation achieved through direct manipulation) for use in cadaveric experimental testing of the hand, wrist, forearm, or elbow. We present a brief motivation for development of this device, design details, an overview of one possible application, and ways to use this device for active pronation and supination activities (rotation achieved through tendon loading). We aim to provide the necessary information for reproduction of this device by other institutions for similar testing purposes

Observation of Changes in the Atomic and Electronic Structure of Single-Crystal YBa₂Cu₃O₆.₆ Accompanying Bromination

To ascertain the role of bromination in the recovery of superconductivity in underdoped YBa2Cu3O6+y (YBCO), we have performed polarized multiple-edge x-ray-absorption fine structure (XAFS) measurements on normal (y~0.6) and brominated (Br/Cu~1/30, y~0.6) single crystals with superconducting transitions at 63 and 89 K, respectively. The brominated sample becomes strongly heterogeneous on an atomic length scale. Approximately one-third of YBCO is locally decomposed yet incorporated as a well-ordered host lattice as nanoscale regions. The decomposed phase consists of heavily distorted domains with an order not following that of the host lattice. Structurally, these domains are fragments of the YBCO lattice that are discontinued along the Cu(1)-O(1) containing planes. The local structure is consistent with the cluster expansions: Y-O(2,3)8-Cu(2)8-..., Ba-O8-Cu(2)4Cu(1)2-..., and Cu-O4... about the Y, Ba, and Cu sites. Interatomic distances and Debye-Waller factors for the expansions were determined from fits to Y K-, Ba L3-, and Cu K-edge XAFS data at room temperature. Br K-edge data reveal that Br does not enter substitutionally or interstitially into the perfect YBCO lattice. However, Br does occupy the Cu(1) sites in a nanofragment of the YBCO lattice, forming Br-O(4)-Ba-Cu2(1)Cu(2)-... nanoclusters. From polarized measurements these nanoclusters were found to be almost randomly oriented with respect to the host crystal, and probably are the nucleus of the decomposed phase. This heterogeneity brings about the unusual structural and electronic properties of the normal state previously reported in the literature. Implications on for diffraction, transport, and magnetization measurements are discussed

Guiding neutral atoms around curves with lithographically patterned current-carrying wires

Laser-cooled neutral atoms from a low-velocity atomic source are guided via a magnetic field generated between two parallel wires on a glass substrate. The atoms bend around three curves, each with a 15-cm radius of curvature, while traveling along a 10-cm-long track. A maximum flux of 2*10^6 atoms/sec is achieved with a current density of 3*10^4 A/cm^2 in the 100x100-micrometer-cross-section wires. The kinetic energy of the guided atoms in one transverse dimension is measured to be 42 microKelvin.Comment: 9 page

Agent-based-model of students’ sociocognitive learning process in acquiring tiered knowledge

Peer reviewe

A Comparison of Stimulus Set Size on Tact Training for Children with Autism Spectrum Disorder

Previous studies on skill acquisition have taught targets in stimulus sets composed of different numbers of stimuli. Although the rationale for selection of a stimulus set size is not clear, the number of target stimuli trained within a set is a treatment decision for which there is limited empirical support. The current investigation compared the efficiency of tact training in 4 stimulus set sizes, each of which included 12 stimuli grouped into (a) 4 sets of 3 stimuli, (b) 3 sets of 4 stimuli, (c) 2 sets of 6 stimuli, and (d) 1 set of 12 stimuli. Results of all 4 participants with autism spectrum disorder show tact training with larger (i.e., 6 and 12) stimulus set sizes was more efficient than training with smaller (i.e., 3 and 4) stimulus set sizes

Two-stage evolution of mantle peridotites from the Stalemate Fracture Zone, northwestern Pacific

This paper reports the results of a mineralogical study of 14 mantle peridotite samples dredged in 2009 from the eastern slope of the northwestern segment of the Stalemate Ridge in the northwestern Pacific during cruise SO201-KALMAR Leg 1b of the R/V Sonne. The sample collection included four serpentinized and silicified dunites and ten variably serpentinized lherzolites. The compositions of primary minerals (clinopyroxene, orthopyroxene, and spinel) change systematically from the lherzolites to dunites. Spinel from the lherzolites shows higher Mg# and lower Cr# values (0.65-0.68 and 0.26-0.33, respectively) compared with spinel from the dunites (Mg# = 0.56-0.64 and Cr# = 0.38-0.43). Clinopyroxene from the lherzolites is less magnesian (Mg# = 91.7-92.4) than clinopyroxene from dunite sample DR37-3 (Mg# = 93.7). Based on the obtained data, it was concluded that the lherzolites of the Stalemate Fracture Zone were derived by 10-12% near-fractional melting of a DMM-type depleted mantle reservoir beneath the Kula-Pacific spreading center. The dunites were produced by interaction of residual lherzolites with sodium- and titaniumrich melt and are probably fragments of a network of dunite channels in the shallow mantle. The moderately depleted composition of minerals clearly distinguishes the lherzolites from the strongly depleted peridotites of the East Pacific Rise and indicates the existence of slow-spreading mid-ocean ridges in the Pacific Ocean during the Cretaceous-Paleogene

Comparing Skill Acquisition Under Varying Onsets of Differential Reinforcement: A Preliminary Analysis

The purpose of the current study was to evaluate the effect of implementing differential reinforcement at different times relative to the onset of teaching new skills to learners with autism spectrum disorder. Specifically, we first determined the most efficient differential reinforcement arrangement for each participant. Using the most efficient arrangement, we evaluated if differential reinforcement from the immediate onset, early onset, or late onset is the most efficient for learners to acquire a new skill. Three children diagnosed with autism spectrum disorder who have a history of receiving intervention based on the principles of applied behavior analysis participated in this study. The immediate onset of differential reinforcement resulted in the most efficient instruction in 6 of 7 comparisons. The results are discussed in light of previous studies and suggestions for future research are provided

An Evaluation of Parent Preference for Prompting Procedures

Parent participation in intervention can enhance intervention efficacy and promote generalization of skills across settings. Thus, parents should be trained to implement behavioral interventions. The purpose of the current investigation was to evaluate parent preference for and acceptability of 3 commonly used prompting procedures. We trained parents of children with disabilities to use 3 empirically validated prompting strategies (i.e., least‐to‐most, most‐to‐least, and a progressive‐prompt delay). Once the parent reached the mastery criteria with each prompting procedure, we evaluated his/her preference for each of the procedures using a concurrent‐chains arrangement. We also measured treatment acceptability of all procedures throughout the study. All participants met the mastery criteria for each of the prompting procedures and showed a preference for least‐to‐most prompting. Results suggest parents\u27 acceptability of procedures prior to training were different than posttraining/post‐child practice. In addition, acceptability rating scores obtained at the end of the investigation corresponded to preference of intervention during the concurrent‐chains arrangement. The results demonstrate the benefits of objective measures for studying preference for behavioral, skill‐acquisition procedures

von Willebrand disease: proposing definitions for future research

Thrombosis and Hemostasi