An Infrasonic Missing Fundamental Rises at 18.5Hz

The Missing Fundamental (MF) phenomenon is an auditory processing artifact which arises from the perception of a harmonically-structured complex sound in the absence of the complex sound’s fundamental frequency (f0). Constructive interference occurring between constituent waveforms of the harmonic series may elicit a perceptible tone at the f0’s pitch. A related illusion, known as binaural auditory beats (BAB), may also generate nonexistent perceptible pitches through a shared mechanism. A harmonic series suggesting to an infrasonic f0 (1/f) noise and broken MF conditions. This data suggests that an infrasonic MF tone is generated, despite the normally imperceptible nature of the sound. The computational phenomenon reported here may also occur throughout the cortex, where it could influence or induce different conscious states. The practical implications of altering cortical activity is relevant in understanding processing disorders such as Attention Deficit Hyperactivity Disorder and Schizophrenia

Reproduction and Dispersal of Biological Soil Crust Organisms

Biological soil crusts (BSCs) consist of a diverse and highly integrated community of organisms that effectively colonize and collectively stabilize soil surfaces. BSCs vary in terms of soil chemistry and texture as well as the environmental parameters that combine to support unique combinations of organisms—including cyanobacteria dominated, lichen-dominated, and bryophyte-dominated crusts. The list of organismal groups that make up BSC communities in various and unique combinations include—free living, lichenized, and mycorrhizal fungi, chemoheterotrophic bacteria, cyanobacteria, diazotrophic bacteria and archaea, eukaryotic algae, and bryophytes. The various BSC organismal groups demonstrate several common characteristics including—desiccation and extreme temperature tolerance, production of various soil binding chemistries, a near exclusive dependency on asexual reproduction, a pattern of aerial dispersal over impressive distances, and a universal vulnerability to a wide range of human-related perturbations. With this publication, we provide literature-based insights as to how each organismal group contributes to the formation and maintenance of the structural and functional attributes of BSCs, how they reproduce, and how they are dispersed. We also emphasize the importance of effective application of molecular and microenvironment sampling and assessment tools in order to provide cogent and essential answers that will allow scientists and land managers to better understand and manage the biodiversity and functional relationships of soil crust communities

Statistical mechanics of dimers on quasiperiodic tilings

We study classical dimers on two-dimensional quasiperiodic Ammann-Beenker (AB) tilings. Despite the lack of periodicity we prove that each infinite tiling admits 'perfect matchings' in which every vertex is touched by one dimer. We introduce an auxiliary 'AB$^*$' tiling obtained from the AB tiling by deleting all 8-fold coordinated vertices. The AB$^*$ tiling is again two-dimensional, infinite, and quasiperiodic. The AB$^*$ tiling has a single connected component, which admits perfect matchings. We find that in all perfect matchings, dimers on the AB$^*$ tiling lie along disjoint one-dimensional loops and ladders, separated by 'membranes', sets of edges where dimers are absent. As a result, the dimer partition function of the AB$^*$ tiling factorizes into the product of dimer partition functions along these structures. We compute the partition function and free energy per edge on the AB$^*$ tiling using an analytic transfer matrix approach. Returning to the AB tiling, we find that membranes in the AB$^*$ tiling become 'pseudomembranes', sets of edges which collectively host at most one dimer. This leads to a remarkable discrete scale-invariance in the matching problem. The structure suggests that the AB tiling should exhibit highly inhomogenous and slowly decaying connected dimer correlations. Using Monte Carlo simulations, we find evidence supporting this supposition in the form of connected dimer correlations consistent with power law behaviour. Within the set of perfect matchings we find quasiperiodic analogues to the staggered and columnar phases observed in periodic systems.Comment: 33 pages, 26 figure

PVR: Patch-to-Volume Reconstruction for Large Area Motion Correction of Fetal MRI

In this paper we present a novel method for the correction of motion artifacts that are present in fetal Magnetic Resonance Imaging (MRI) scans of the whole uterus. Contrary to current slice-to-volume registration (SVR) methods, requiring an inflexible anatomical enclosure of a single investigated organ, the proposed patch-to-volume reconstruction (PVR) approach is able to reconstruct a large field of view of non-rigidly deforming structures. It relaxes rigid motion assumptions by introducing a specific amount of redundant information that is exploited with parallelized patch-wise optimization, super-resolution, and automatic outlier rejection. We further describe and provide an efficient parallel implementation of PVR allowing its execution within reasonable time on commercially available graphics processing units (GPU), enabling its use in the clinical practice. We evaluate PVR's computational overhead compared to standard methods and observe improved reconstruction accuracy in presence of affine motion artifacts of approximately 30% compared to conventional SVR in synthetic experiments. Furthermore, we have evaluated our method qualitatively and quantitatively on real fetal MRI data subject to maternal breathing and sudden fetal movements. We evaluate peak-signal-to-noise ratio (PSNR), structural similarity index (SSIM), and cross correlation (CC) with respect to the originally acquired data and provide a method for visual inspection of reconstruction uncertainty. With these experiments we demonstrate successful application of PVR motion compensation to the whole uterus, the human fetus, and the human placenta.Comment: 10 pages, 13 figures, submitted to IEEE Transactions on Medical Imaging. v2: wadded funders acknowledgements to preprin

Technology And Teaching Screencast Tutorials Enhance Student Learning of Statistics

Abstract Although the use of computer-assisted instruction has rapidly increased, there is little empirical research evaluating these technologies, specifically within the context of teaching statistics. The authors assessed the effect of screencast tutorials on learning outcomes, including statistical knowledge, application, and interpretation. Students from four sections of a psychology course in statistics were randomly assigned to a control text tutorial or an experimental video tutorial group and were tasked with completing a novel statistics problem. Previous math experience, math and computer anxiety, and course grades were also controlled. The results demonstrate that screencast tutorials are an effective and efficient tool for enhancing student learning, especially for higher order conceptual statistical knowledge compared to traditional instructional techniques

Masses of Astrometrically-Discovered and Imaged Binaries: G 78-28AB and GJ 231.1BC

The Stellar Planet Survey (STEPS) is an ongoing astrometric search for giant planets and brown dwarfs around a sample of ~30 M-dwarfs. We have discovered several low-mass companions by measuring the motion of our target stars relative to their reference frames. The highest mass discovery thus far is G 78-28B, a companion to the M-dwarf G 78-28A. The orbital period is 4.18 +/- 0.03 y, the system mass is 0.565 +/- 0.055 Msolar, and the semi-major axis is 2.19 +/- 0.10 AU. Imaging observations with the Keck laser guide star adaptive optics (LGSAO) and the Palomar AO instruments resolved the system and also yielded JHK-band delta magnitudes. We use the orbital solution, light ratios, and mass-luminosity relationships to derive component masses of MA = 0.370 +/- 0.034 Msolar and MB = 0.195 +/- 0.021 Msolar. G 78-28B is of type M4 V based upon its colors and mass. We also discovered GJ 231.1C, a companion to GJ 231.1B, with STEPS and imaged the companion with LGSAO and Palomar AO, but the orbital period is longer than our observing baseline; thus the system parameters are less constrained. In GJ 231.1BC the masses are MB = 0.25 +/- 0.06 Msolar and MC =0.12 +/- 0.02 Msolar. The inferred spectral type of GJ 231.1C is M5 V. We demonstrate the results of the current state of mass estimation techniques with our data.Comment: 25 pages, 8 figures, accepted for Ap

An Automated Method for the Detection and Extraction of HI Self-Absorption in High-Resolution 21cm Line Surveys

We describe algorithms that detect 21cm line HI self-absorption (HISA) in large data sets and extract it for analysis. Our search method identifies HISA as spatially and spectrally confined dark HI features that appear as negative residuals after removing larger-scale emission components with a modified CLEAN algorithm. Adjacent HISA volume-pixels (voxels) are grouped into features in (l,b,v) space, and the HI brightness of voxels outside the 3-D feature boundaries is smoothly interpolated to estimate the absorption amplitude and the unabsorbed HI emission brightness. The reliability and completeness of our HISA detection scheme have been tested extensively with model data. We detect most features over a wide range of sizes, linewidths, amplitudes, and background levels, with poor detection only where the absorption brightness temperature amplitude is weak, the absorption scale approaches that of the correlated noise, or the background level is too faint for HISA to be distinguished reliably from emission gaps. False detection rates are very low in all parts of the parameter space except at sizes and amplitudes approaching those of noise fluctuations. Absorption measurement biases introduced by the method are generally small and appear to arise from cases of incomplete HISA detection. This paper is the third in a series examining HISA at high angular resolution. A companion paper (Paper II) uses our HISA search and extraction method to investigate the cold atomic gas distribution in the Canadian Galactic Plane Survey.Comment: 39 pages, including 14 figure pages; to appear in June 10 ApJ, volume 626; figure quality significantly reduced for astro-ph; for full resolution, please see http://www.ras.ucalgary.ca/~gibson/hisa/cgps1_survey

Trends and Issues with the English Assessment and Class Placement of First Year Students at Kyoei University : Department of International Business Management

本論文は、2009 ～ 2011 年に共栄大学国際経営学部(IBMD) に入学した学生の英語の能力の低下について述べたものである。本論は、クラス分けテストの得点と毎年の傾向を議論した上で、英語のカリキュラムが大きく変わっ現在でも、これ迄同様のクラス分けテストの存在意義、必要性について述べている。又、クラス分けの不適合は、学生の、(授業が簡単すぎたり難しすぎたりしての)退屈な授業の受講、学習意欲の消失、幻滅、無断欠席、と一連の流れに陥り最終的に退学という最悪の結果にもなりかねない事も書き加えている。This paper discusses the decline in the English ability of students entering the InternationalBusiness Management Department (IBMD) of Kyoei University between 2009 and 2011, and discussesthe placement test scores and yearly trends. It also questions the administration\u27s rationalefor administering the current test in the light of recent English curriculum changes, and the pre-assigningof students to English classes according to demands completely unrelated to their Englishlanguage educational needs. In addition, the paper discusses the de-motivation, boredom and disillusionmentthat may occur due to class miss-assignment, and its possible links to truancy and dropout rates

キョウエイ ダイガク プレースメント テスト ニタイスル ヒョウカ

この論文は、初めての試みである2010 年共栄大学プレースメント・テストにおける分析を主旨とする。このテストは、依然として多くの微調整や課題を要するものの、その統計的な分析の結果、その実践における確固たる有効性を証明することができた。このテストは、プレースメント・テストとしては、その信頼性においてもその目的を果たすものして適切なものであるということがこの論文における統計分析でよって証明ができたと言える。さらにこのテストをモデルとして、今後のプレースメント・テストにおける将来的な展望が大いに開けたと言えよう。This paper discusses the development, and analysis of the newly developed placement test forthe 2010 International Business Management Department (IBMD) first year intake. It acknowledgesthat while a small number of items may need further examination or improvement, the statisticalanalysis provides solid empirical evidence about the performance of the test. It is clear that the testis suitable for the purpose for which it was designed and that the satisfactory reliability and validityevidence gathered proves that it is a dependable test. Moreover it demonstrates that this test can beused with confidence now, and as a model on which to build future versions