bluuebunny/crossref_metadata_2025 huggingface dataset:
Observations of the effect of emergent vegetation on sediment resuspension under unidirectional currents and waves
Authors: Tinoco R. O. , Coco G.
Published: January 2014

Abstract. We present results from a series of laboratory experiments on a wave and current flume, where synchronous velocity and concentration measurements were acquired within arrays of rigid cylinders, representative of emergent vegetation and benthic communities, under different flow conditions. The density of an array of rigid cylinders protruding through a sandy bed affects the velocity field, sediment motion and resuspension thresholds when subjected to both unidirectional currents and regular waves. We compare the measured resuspension thresholds against predictions of sediment motion on non-obstructed flows over sandy beds. The results show that even if flow speeds are significantly reduced within the array, the coherent flow structures and turbulence generated within the array can enhance sediment resuspension depending on the population density.
Extracting topographic swath profiles across curved geomorphic features
Authors: Hergarten S. , Robl J. , Stüwe K.
Published: January 2014

Abstract. We present a new method to extend the widely used geomorphic technique of swath profiles towards curved geomorphic structures such as river valleys. In contrast to the established method that hinges on stacking parallel cross sections, our approach does not refer to any individual profile lines, but uses the signed distance from a given baseline (for example, a valley floor) as the profile coordinate. The method can be implemented easily for arbitrary polygonal baselines and for rastered digital elevation models as well as for irregular point clouds such as laser scanner data. Furthermore it does not require any smoothness of the baseline and avoids over- and undersampling due to the curvature of the baseline. The versatility of the new method is illustrated by its application to topographic profiles across valleys, a large subduction zone, and the rim of an impact crater. Similarly to the ordinary swath profile method, the new method is not restricted to analyzing surface elevations themselves, but can aid the quantitative description of topography by analyzing other geomorphic features such as slope or local relief. It is even not constrained to geomorphic data, but can be applied to any two-dimensional data set such as temperature, precipitation or ages of rocks.
divand-1.0: n-dimensional variational data analysis for ocean observations
Authors: Barth A. , Beckers J.-M. , Troupin C. , Alvera-Azcárate A. , Vandenbulcke L.
Published: January 2014

Abstract. A tool for multidimensional variational analysis (divand) is presented. It allows the interpolation and analysis of observations on curvilinear orthogonal grids in an arbitrary high dimensional space by minimizing a cost function. This cost function penalizes the deviation from the observations, the deviation from a first guess and abruptly varying fields based on a given correlation length (potentially varying in space and time). Additional constraints can be added to this cost function such as an advection constraint which forces the analysed field to align with the ocean current. The method decouples naturally disconnected areas based on topography and topology. This is useful in oceanography where disconnected water masses often have different physical properties. Individual elements of the a priori and a posteriori error covariance matrix can also be computed, in particular expected error variances of the analysis. A multidimensional approach (as opposed to stacking two-dimensional analysis) has the benefit of providing a smooth analysis in all dimensions, although the computational cost is increased. Primal (problem solved in the grid space) and dual formulations (problem solved in the observational space) are implemented using either direct solvers (based on Cholesky factorization) or iterative solvers (conjugate gradient method). In most applications the primal formulation with the direct solver is the fastest, especially if an a posteriori error estimate is needed. However, for correlated observation errors the dual formulation with an iterative solver is more efficient. The method is tested by using pseudo-observations from a global model. The distribution of the observations is based on the position of the Argo floats. The benefit of the three-dimensional analysis (longitude, latitude and time) compared to two-dimensional analysis (longitude and latitude) and the role of the advection constraint are highlighted. The tool divand is free software, and is distributed under the terms of the General Public Licence (GPL) (http://modb.oce.ulg.ac.be/mediawiki/index.php/divand).
A new mixed-mode fracture criterion for large-scale lattice models
Authors: Sachau T. , Koehn D.
Published: January 2014

Abstract. Reasonable fracture criteria are crucial for the modeling of dynamic failure in computational lattice models. Successful criteria exist for experiments on the micro- and on the mesoscale, which are based on the stress that a bond experiences. In this paper, we test the applicability of these failure criteria to large-scale models, where gravity plays an important role in addition to the externally applied deformation. Brittle structures, resulting from these criteria, do not resemble the outcome predicted by fracture mechanics and by geological observations. For this reason we derive an elliptical fracture criterion, which is based on the strain energy stored in a bond. Simulations using the new criterion result in realistic structures. It is another great advantage of this fracture model that it can be combined with classic geological material parameters: the tensile strength σ0 and the shear cohesion τ0. The proposed fracture criterion is much more robust with regard to numerical strain increments than fracture criteria based on stress (e.g., Drucker–Prager). While we tested the fracture model only for large-scale structures, there is strong reason to believe that the model is equally applicable to lattice simulations on the micro- and on the mesoscale.
Risk to life due to flooding in post-Katrina New Orleans
Authors: Miller A. , Jonkman S. N. , Van Ledden M.
Published: January 2014

Abstract. After the catastrophic flooding of New Orleans due to hurricane Katrina in the year 2005, the city's hurricane protection system has been improved to provide protection against a hurricane load with a 1/100 per year exceedance frequency. This paper investigates the risk to life in post-Katrina New Orleans. In a risk-based approach the probabilities and consequences of various flood scenarios have been analyzed for the central area of the city (the metro bowl) to give a preliminary estimate of the risk to life in the post-Katrina situation. A two-dimensional hydrodynamic model has been used to simulate flood characteristics of various breaches. The model for estimation of fatality rates is based on the loss of life data for Hurricane Katrina. Results indicate that – depending on the flood scenario – the estimated loss of life in case of flooding ranges from about 100 to nearly 500, with the highest life loss due to breaching of the river levees leading to large flood depths. The probability and consequence estimates are combined to determine the individual risk and societal risk for New Orleans. When compared to risks of other large scale engineering systems (e.g. other flood prone areas, dams and the nuclear sector) and acceptable risk criteria found in literature, the risks for the metro bowl are found to be relatively high. Thus, despite major improvements to the flood protection system, the flood risk of post-Katrina New Orleans is still expected to be significant. Effects of reduction strategies on the risk level are discussed as a basis for further evaluation.
Classification of homoclinic rogue wave solutions of the nonlinear Schrödinger equation
Authors: Osborne A. R.
Published: January 2014

Abstract. Certain homoclinic solutions of the nonlinear Schrödinger (NLS) equation, with spatially periodic boundary conditions, are the most common unstable wave packets associated with the phenomenon of oceanic rogue waves. Indeed the homoclinic solutions due to Akhmediev, Peregrine and Kuznetsov-Ma are almost exclusively used in scientific and engineering applications. Herein I investigate an infinite number of other homoclinic solutions of NLS and show that they reduce to the above three classical homoclinic solutions for particular spectral values in the periodic inverse scattering transform. Furthermore, I discuss another infinity of solutions to the NLS equation that are not classifiable as homoclinic solutions. These latter are the genus-2N theta function solutions of the NLS equation: they are the most general unstable spectral solutions for periodic boundary conditions. I further describe how the homoclinic solutions of the NLS equation, for N = 1, can be derived directly from the theta functions in a particular limit. The solutions I address herein are actual spectral components in the nonlinear Fourier transform theory for the NLS equation: The periodic inverse scattering transform. The main purpose of this paper is to discuss a broader class of rogue wave packets1 for ship design, as defined in the Extreme Seas program. The spirit of this research came from D. Faulkner (2000) who many years ago suggested that ship design procedures, in order to take rogue waves into account, should progress beyond the use of simple sine waves. 1An overview of other work in the field of rogue waves is given elsewhere: Osborne 2010, 2012 and 2013. See the books by Olagnon and colleagues 2000, 2004 and 2008 for the Brest meetings. The books by Kharif et al. (2008) and Pelinovsky et al. (2010) are excellent references.
ERITEMINĖS ULTRAVIOLETINĖS SPINDULIUOTĖS POKYČIŲ ANALIZĖ
Authors: Chadyšienė Renata , Girgždys Aloyzas
Published: January 2014

In this article the erythemally weighted UV radiation intensity variations during 2002-2011 were analysed. Also UV radiation intensity and total ozone data in this paper were analysed, because the UV index is directly dependent on the intensity of UV radiation, and most of the UV radiation is absorbed by stratospheric ozone. During 2002-2011 in the course of UV index - the upward trend was observed, and in the total ozone values - the downward trend was observed. During the investigated period in Lithuania the maximum UV index values (very high) on clear sky summer days were determined.
NERIMO IR DEPRESIJOS SIMPTOMŲ RAIŠKA ADAPTACIJOS SUTRIKIMŲ ATVEJU
Authors: Miškinytė Audronė , Adomaitienė Virginija
Published: January 2014

Adjustment disorder research has not yet disclosed the relationship of anxiety and depression symptoms with gender and age. It is assumed that emotional reactions are related to individual characteristics of personality and stressors that influence social adjustment. The goal of this study was to determine the expression of anxiety and depression symptoms in psychological assessment of adjustment disorders. Methods. 153 psychological assessment protocols of hospitalized adjustment disorder patients were analyzed retrospectively. MMPI-2 and Luscher color test data was analyzed. Results. Women attribute significantly more anxiety symptoms to themselves than men (p = 0,023). Hypothondriasis and Depression scale elevations dominate in men and women‘s profiles that indicate difficulties in identifying emotional experiences, especially anxiety, and possible somatization of anxiety. Depression symptoms are attributed to oneself most commonly. Experiences of anxiety dominate in a projective test. Men tend to cover anxiety by strengthening self-control, emphasizing their independency and self-confidence, when women tend to withdraw. Conclusions. Objective test determined self-attributed depression symptoms and somewhat anxiety. Projective test determined anxiety and no depression symptoms. The behavior is mostly determined by anxiety rather than depression symptoms. The expression of anxiety differs depending on gender and age.
Western Faculty Profile: Dr. Jan Cami
Authors: Huang Eva Y.
Published: January 2014

Dr. Jan Cami is an Associate Professor at Western University, currently teaching both undergraduate and graduate courses in astronomy, including fourth year undergraduate honours research projects. Dr. Cami's main research areas include molecular spectroscopy, dust mineralogy in evolved stars, and the Diffuse Interstellar Bands (DIBs). He has received the Western Faculty Scholar Award, international awards from NASA, and has an undeniable passion for scientific community outreach, something he is actively involved in and promotes. WURJHNS Academic Affairs Co-ordinator, Eva Huang, had the chance to interview him to learn more about his career path, his past and current work, and his time at Western.
An inquiline deep-water bryozoan/amphipod association from New Zealand, including the description of a new genus and species of Chevaliidae
Authors: Lörz Anne-Nina , Myers Alan , Gordon Dennis
Published: January 2014

For the first time Amphipoda have been discovered living in Bryozoa. A new genus and species of the amphipod family Chevaliidae, Bryoconversor tutus gen. et sp. nov. is described from New Zealand at 530–1500 m depth. The species lives in an inquiline relationship with the cheilostome bryozoan Onchoporoides moseleyi (Calwelliidae), inhabiting an abfrontal basal coelom of the bryozoan beneath the membranous ectocyst (cuticularized epithelium) that conceals and protects the amphipods. The colony is strengthened along all edges by a unique intracoelomic rod of calcium carbonate that is formed within the marginal kenozooids of the colony. The potential benefits and costs to the bryozoan are discussed.
Quick Reads: The Different Representations of Rational Numbers
Authors: Beyranevand Matthew L.
Published: January 2014

Students' preferences when working with particular representations are explored.
Teacher Leaders Advancing Mathematics Learning
Authors: Kinzer Cathy J. , Rincón Mari , Ward Jana , Rincón Ricardo , Gomez Lesli
Published: January 2014

Four elementary school instructors offer insights into their classrooms, their unique professional roles, and their leadership approaches.
Identification of major welfare issues for captive elephant husbandry by stakeholders
Authors: Gurusamy V , Tribe A , Phillips CJC
Published: January 2014

Accurate identification of key welfare issues for captive elephants could improve standards and help in the development of a welfare index. In the absence of adequate scientific information on the relative importance of key issues, the views of a range of stakeholders were sought using adaptive conjoint analysis. Fifteen key welfare issues were identified by experts, and three to six Levels of each, representing common husbandry practices. In order of declining importance, 224 stakeholders rated the issues as enclosure substrate > group size > healthcare > enrichment > chaining > enclosure type > exercise provision > enclosure size > interaction with keeper > enclosure environment > keeper knowledge/experience > diet > contact method with keeper > display duration > enclosure security. Enclosure size was considered more important by scientists and keepers than zoo directors/managers and animal welfare organisation representatives. Animal welfare organisation representatives rated enclosure security higher than scientists. Keeper husbandry methods and ability of elephants to be active were two principal components in responses. Three principal groups of respondents were identified: scientists/veterinarians focusing more on conditions for the elephants and less on interaction with the public; keepers, focusing on keeper contact method, feeding and knowledge of elephants; and a group with mainly animal welfare organisation representatives/zoo directors focusing on enclosure security. It is concluded that there are some differences between stakeholders in their recognition of the most important welfare issues for elephants in zoos. However, recognising that a diversity of informed opinion is necessary to adequately devise welfare standards, an index of elephant welfare in zoos is proposed, based on the relative merits of different husbandry practices and the importance of the different issues.
The welfare of long-line tethered and free-ranging horses kept on public grazing land in South Wales
Authors: Mullan S , Szmaragd C , Hotchkiss J , Whay HR
Published: January 2014

A welfare assessment was conducted during 475 observations of 75 long-line tethered horses and 587 observations of 112 freerange horses kept on public grazing land in South Wales over a six-month period from March to August 2010. The observations included quantitative and qualitative behavioural assessments, assessments of physical welfare and assessments of the environment of the horse. Multi-level modelling was used to identify the significant factors affecting each measure. Tethered horses had similar behavioural repertoires to free-range horses but there were differences related to tethering, such as fewer observations of walking, trotting and cantering, increased vocalisations occurring during the observation and poorer qualitative ‘mood’ scores. There were few observations of severe physical welfare problems in either tethered or free-range horses, however tethered horses were observed more often to have eye abnormalities, hoof cracks, lameness and signs of limb pain but less often with mane and tail tangles, as thin or as dirty. Shelter from wind, rain or sun was available to almost all free-range horses (99.8% of observations) but was only found during 16.5% or fewer observations of tethered horses, giving them a greater risk of poor welfare during inclement weather. Similarly, tethered horses were infrequently observed to have access to clean water, and their willingness to drink when offered water, suggests the provision of water was inadequate and tethered horses may have been thirsty. There were significant confounding effects of the observer or climatic factors for some behavioural and physical measures that should be considered when conducting future studies.
Implementing Welfare Quality® in UK assurance schemes: evaluating the challenges
Authors: Heath CAE , Lin Y , Mullan S , Browne WJ , Main DCJ
Published: January 2014

This paper presents an account of a Welfare Quality® assessment of 92 dairy farms carried out by seven experienced assessors. The aim was to evaluate the potential of the Welfare Quality® assessment protocol with respect to its uptake by UK farm assurance schemes. Data collection, and measure aggregation were performed according to the Welfare Quality® protocol for dairy cows. This study examined the data itself, by the testing of how hypothetical interventions might be reflected in changes in the aggregated scores, and also investigated human-related aspects, through inter-assessor standardisation sessions to evaluate reliability, and an assessor focus group to collect feedback. Overall, three main ‘challenges’ were identified. The first challenge related to the large amount of missing data. Unexpectedly, this was such that it was only possible to calculate an overall classification for 7% of farms. The second challenge concerned the way in which aggregated scores did not always reflect hypothetical interventions. The final challenge was inter-assessor reliability, where not all assessors were found to achieve acceptable levels of agreement on a number of outcome measures by the third training session. Suggestions for managing these challenges included, follow-up to assessor training, the use of multiple imputation methods to fill in missing data, and, where applicable, not aggregating the scores. The conclusion of the study was that the protocol provided useful information from which to make an informed selection of measures, but that the challenges, combined with the lengthy assessment time, were too great for its use as a certification tool.
Optical Control of Microspherical Laser Oscillation by Transient Absorption
Authors: Sasaki Keiji , Kamada Kenji , Masuhara Hiroshi
Published: January 2014

A new method for optical control of a lasing process within a microspherical particle has been proposed. A microparticle was doped with a dye for lasing, and with a transient absorber that quenched lasing emission only when excited by light. The quality factor of a microspherical cavity was reduced by the transient absorption loss which could be arbitrarily varied with the excitation intensity, so that the lasing emission intensity was controllable with excitation light. On-off switching of microspherical laser oscillation and picosecond pulse shortening with optical Q-switching are demonstrated as preliminary experiments.
Critical Thickness for Islanded Growth of Highly Strained I
n
x

G
a
1-x

A
s on GaAs(001)
Authors: Grandjean Nicolas , Raymond Jean Massies
Published: January 2014

Above a certain critical thickness, the more stable morphology of a highly strained In

x

Ga1-
x

As layer on GaAs(001) is an islanded configuration. The strain relaxation occurs mainly at the free-edges of islands and thus increases when the epilayer evolves from a two-dimensional (2D) to a three-dimensional (3D) morphology. A simple model taking into account this relaxation process as well as surface energy creation correctly predicts the critical thickness for which the 2D-3D growth mode transition is observed under usual growth conditions for this prototypical highly-mismatched system.
DC electrical conductivity study of amorphous carbon nitride films prepared by reactive RF magnetron sputtering
Authors: Tamura Naoyuki , Aono Masami , Harata Tomo , Kishimura Hiroaki , Kitazawa Nobuaki , Watanabe Yoshihisa
Published: January 2014

The effects of chemical bonding states on the electrical properties of hydrogen-free amorphous carbon nitride (a-CN
x
) films were reported. a-CN
x
films were prepared by reactive RF magnetron sputtering at various deposition temperatures. The electrical conductivity of the a-CN
x
films increased with increasing deposition temperature because of the predominant sp2C–C bonding sites. Their conductivity increased by almost one order of magnitude with a 25% decrease in the fraction of the N-sp3C bonding state. It was found that the fraction of the N-sp2C bonding state strongly contributed to the increase in the electrical conductivity. Nitrogen incorporation led to an increase in the sp3C–C bonding fraction in the films; as a result, the conductivity of the a-CN
x
films was found to be lower than that of the a-C films deposited under the same conditions.
Synthesis of CxSr2Ca(
n
−1)CunOz superconductors using high-pressure-synthesized Sr2Ca(
n
−1)CunOy precursors (n = 2, 4)
Authors: Aoba Tomoya , Suzuki Tsuneo , Nakayama Tadachika , Suematsu Hisayuki , Niihara Koichi
Published: January 2014

Novel compounds of C
x
Sr2CaCu2O
z
and C
x
Sr2Ca3Cu4O
z
were derived by annealing high pressure-synthesized samples of Sr2Ca(

n

−1)Cu
n
O
y
(n = 2, 4) at 350 °C for 30 min in air. Energy-dispersive X-ray spectroscopy and electron energy loss spectroscopy indicated the composition of Sr, Ca, and Cu was not changed from the original materials and the C-K edge energy loss near edge structure was similar to that of CaCO3. It is likely that carbonate groups are incorporated either from air or secondary-phase grains into the pristine 0(Sr)2(n − 1)n structure to form the C
x
Sr2Ca(

n

−1)Cu
n
O
z
compounds during the annealing. Magnetization measurements revealed superconductivity with T
c,onset = 89 K for C
x
Sr2CaCu2O
z
and 65 K for C
x
Sr2Ca3Cu4O
z
.
Lattice distortions and piezoelectric properties in (Bi3.25Nd0.75−
xEux)Ti3O12 nanoplates with a- and b-axis orientations
Authors: Kobune Masafumi , Kugimiya Takuya , Kaneko Yusaku , Ueshima Satoshi , Kikuchi Takeyuki , Fukumuro Naoki , Matsuda Hitoshi , Fukushima Koji , Fujisawa Hironori , Nakashima Seiji , Shimizu Masaru
Published: January 2014

a- and b-axis-oriented (Bi3.25Nd0.75−

x
Eu
x
)Ti3O12 (BNEuT, x = 0–0.75) films of 3.0 µm thickness were fabricated on conductive Nb:TiO2(101) substrates containing 0.79 mass % Nb by high-temperature sputtering at 650 °C, and their structural and piezoelectric characteristics were investigated. The room-temperature remanent polarization (2P
r) and effective piezoelectric coefficient (d
33) values for the BNEuT films exhibited maxima of 87 µC/cm2 and 15 pm/V, respectively, at x = 0.10, which were approximately 1.3 times larger than those (2P
r = 65 µC/cm2 and d
33 = 12 pm/V) of the nondoped (Bi3.25Nd0.75)Ti3O12 (BNT) nanoplate. The BNEuT film with x = 0.10 had a high a-axis orientation judging from the X-ray diffraction measurement and the observation of the phase image by piezoresponse force microscopy. It is shown that adequate Eu3+ doping of BNT nanoplates produces a larger displacement magnitude of the octahedra than that in the nondoped BNT nanoplate, resulting in an improvement of piezoelectric properties in addition to the ferroelectricity.
Synthesis of Zr-based perovskite-type alloy phosphors by polymerized complex method
Authors: Komagata Hiroki , Kato Riku , Kato Ariyuki
Published: January 2014

To demonstrate the fabrication of inorganic electroluminescent (EL) devices using perovskite-type oxide phosphors by electrophoretic deposition (EPD), AZrO3:RE (A = Ca, Sr, Ba; RE = Eu, Tb) were synthesized by the polymerized complex method. AZrO3:Eu showed orange or red emissions and AZrO3:Tb showed blue-green or green emissions depending on their crystal structures. The emission intensity was found to be enhanced by introducing strains to the host matrices by Mg codoping or alloying. Inorganic EL devices prepared by EPD using BaZrO3:Eu and SrZrO3:Eu as the phosphor layers showed orange and blue emissions that were observable under room light, respectively, which is the first observation of EL emission from the devices prepared by EPD to the best of our knowledge. The combination of perovskite-type oxide phosphors and EPD was found to be a promising way to fabricate inorganic EL devices.
Current-induced magnetization switching at low current densities in current-perpendicular-to-plane structural Fe3Si/FeSi2 artificial lattices
Authors: Sakai Ken-ichiro , Noda Yūta , Daio Takeshi , Tsumagari Daiki , Tominaga Aki , Takeda Kaoru , Yoshitake Tsuyoshi
Published: January 2014

Current-perpendicular-to-plane (CPP) junctions of Fe3Si/FeSi2 were fabricated from Fe3Si/FeSi2 artificial lattice films, which were prepared by facing-target direct-current sputtering, by employing a focused ion beam (FIB) technique. CPP structurization was confirmed by scanning electron microscopy. The CPP junctions, in which antiferromagnetic interlayer coupling is induced between the Fe3Si layers, exhibited a clear hysteresis loop in the electrical resistance for current injection, which is probably due to current-induced magnetization switching. The critical current density for it is approximately 3.3 × 101 A/cm2, which is at least four orders smaller than the values that have ever been reported.
Development of bifacial inverted polymer solar cells using a conductivity-controlled transparent PEDOT:PSS and a striped Au electrode on the hole collection side
Authors: Kuwabara Takayuki , Katori Shinji , Arima Kazuhiro , Omura Yoshihiro , Yamaguchi Takahiro , Taima Tetsuya , Takahashi Kohshin
Published: January 2014

An inverted bifacial polymer solar cell was developed using a conductivity-controlled transparent poly(3,4-ethylenedioxylenethiophene):poly(4-styrene sulfonic acid) (PEDOT:PSS) as a hole collection layer and a striped Au electrode with a large open aperture ratio (R
ap) as a hole collection electrode. We investigated the performance of the device by varying the interelectrode distance of the striped Au electrode and the sheet resistance of the PEDOT:PSS film. The device using untreated Clevios P (PEDOT:PSS) showed a maximum electric output (P
w) in the R
ap range of 50 to 65%. When alcohol-treated Clevios P (Clevios P+) with a lower electrical resistance was used, the maximum P
w increased by 40% compared with that of the device using Clevios P. The maximum P
w was obtained in the R
ap range of 84% as the hole collection efficiency of the striped Au electrode improved with the decreased sheet resistance of the PEDOT:PSS.
Solid-phase crystallization of amorphous silicon nanowire array and optical properties
Authors: Ishikawa Ryousuke , Kato Shinya , Yamazaki Tatsuya , Kurokawa Yasuyoshi , Miyajima Shinsuke , Konagai Makoto
Published: January 2014

An amorphous silicon nanowire (a-SiNW) array perpendicular to a glass substrate can be successfully obtained through the metal-assisted chemical etching of amorphous silicon (a-Si) thin films. The solid-phase crystallization of a-SiNWs was carried out by thermal annealing in a forming gas in the temperature range from 600 to 900 °C. The effects of hydrogen in the film and the film morphology on the crystallization of a-SiNWs were investigated by Raman spectroscopy and transmission electron microscopy. A higher hydrogen concentration of a-SiNWs reduced the crystallization temperature, as in a-Si thin films. It was also revealed that the large surface area of the a-SiNW array affected the crystallization process. We also studied the optical property of the fabricated SiNW array and demonstrated its high potential as an active layer in solar cells.
Sound velocity of iron up to 152 GPa by picosecond acoustics in diamond anvil cell
Authors: Decremps F. , Antonangeli D. , Gauthier M. , Ayrinhac S. , Morand M. , Marchand G. Le , Bergame F. , Philippe J.
Published: January 2014

High‐pressure method combining diamond anvil cell with picosecond ultrasonics technique is demonstrated to be a very suitable tool to measure the acoustic properties of iron up to 152 GPa. Such innovative approach allows to measure directly the longitudinal sound velocity under pressure of hundreds of GPa in laboratory, overcoming most of the drawbacks of traditional techniques. The very high accuracy, comparable to piezoacoustics technique, allows to observe the kink in elastic properties at the body‐centered cubic–hexagonal close packed transition and to show with a good confidence that the Birch's law still stands up to 1.5 Mbar and ambient temperature. The linear extrapolation of the measured sound velocities versus densities of hcp iron is out of the preliminary reference Earth model, arguing for alloying effects or anharmonic high‐temperature effects. A comparison between our measurements and shock wave experiments allowed us to quantify temperature corrections at constant pressure in ~−0.35 and ~−0.30 m s−1/K at 100 and 150 GPa, respectively. More in general, the here‐presented technique allows detailed elastic and viscoelastic studies under extreme thermodynamic conditions on a wide variety of systems as liquids, crystalline, or polycrystalline solids, metallic or not, with very broad applications in Earth and planetary science.
Relationship between plasma bubbles and density enhancements: Observations and interpretation
Authors: Huang Chao‐Song , Le G. , de La Beaujardiere O. , Roddy P. A. , Hunton D. E. , Pfaff R. F. , Hairston M. R.
Published: January 2014

Plasma bubbles are regions of depleted plasma density in the nighttime equatorial ionosphere. Plasma enhancements, also referred as plasma blobs, are regions where the plasma density is increased. It has not been well understood whether and how plasma enhancements are related to plasma bubbles. In this paper, we present the observations of plasma bubbles and enhancements by the Communication/Navigation Outage Forecasting System (C/NOFS) satellite during 2008 and 2009. In some cases, C/NOFS first detected plasma bubbles near the magnetic equator and then plasma enhancements at the same longitudes but at higher latitudes during subsequent orbits. In other cases, C/NOFS first detected plasma enhancements at off‐equatorial locations and then plasma bubbles near the magnetic equator at the same longitudes. It is also found that plasma enhancements existed just above plasma depletions. We propose a unified scenario to describe the evolution of plasma bubbles and the formation of plasma enhancements. In the proposed scenario, plasma enhancements can occur at different latitudes and altitudes during the early, intermediate, and late stages of the bubble evolution. This scenario provides a reasonable explanation of the observations.
A simple turbulence model for stably stratified wall‐bounded flows
Authors: Karimpour F. , Venayagamoorthy S. K.
Published: January 2014

In this study, we present a simple zero‐equation (algebraic) turbulence closure scheme as well as the standard k‐ϵ model for stably stratified wall‐bounded flows. We do this by proposing a parameterization for the turbulent Prandtl number (Prt) for stably stratified flows under the influence of a smooth solid wall. The turbulent Prandtl number is the linking bridge between the turbulent momentum and scalar fluxes in the context of Reynolds‐averaged Navier‐Stokes (RANS) simulations. Therefore, it is important to use appropriate parameterizations for Prt in order to define the right level of momentum and scalar mixing in stably stratified flows. To date, most of the widely used parameterizations for Prt in stably stratified flows are based on data obtained from homogeneous shear flows experiments and/or direct numerical simulations (i.e., statistics are invariant under translations) and are usually formulated as functions of the gradient Richardson number (Rig). The effect of the wall boundary is completely neglected. We introduce a modified parameterization for Prt that takes into account the inhomogeneity caused by the wall coupled with the effects of density stratification. We evaluate the performance of the modified Prt by using a zero‐equation turbulence model for the turbulent viscosity that was proposed by Munk and Anderson (1948) as well as the standard k‐ϵ model to simulate a one‐dimensional stably stratified channel flow. Comparison of the one‐dimensional simulation results with direct numerical simulation (DNS) of stably stratified channel flow results show remarkable agreement.
Simulated magnetopause losses and Van Allen Probe flux dropouts
Authors: Hudson M. K. , Baker D. N. , Goldstein J. , Kress B. T. , Paral J. , Toffoletto F. R. , Wiltberger M.
Published: January 2014

Three radiation belt flux dropout events seen by the Relativistic Electron Proton Telescope soon after launch of the Van Allen Probes in 2012 (Baker et al., 2013a) have been simulated using the Lyon‐Fedder‐Mobarry MHD code coupled to the Rice Convection Model, driven by measured upstream solar wind parameters. MHD results show inward motion of the magnetopause for each event, along with enhanced ULF wave power affecting radial transport. Test particle simulations of electron response on 8 October, prior to the strong flux enhancement on 9 October, provide evidence for loss due to magnetopause shadowing, both in energy and pitch angle dependence. Severe plasmapause erosion occurred during ~ 14 h of strongly southward interplanetary magnetic field Bz beginning 8 October coincident with the inner boundary of outer zone depletion.
On the conditions preceding sudden magnetotail magnetic flux unloading
Authors: Shukhtina M. A. , Dmitrieva N. P. , Sergeev V. A.
Published: January 2014

According to the substorm paradigm, the tail magnetic flux F is accumulated during the growth phase and suddenly released afterward. However, only 33 out of 142 isolated midtail sudden unloading events identified by Geotail in 1995–1998 demonstrated monotonous F increase (type 1 substorms). In 32 cases, balanced tail flux (BTF) period (F ~constant) with enhanced dissipation and pseudobreakup activity during 0.5–2 h before unloading was registered (type 2, a new substorm class). The rest 77 substorms lie between types 1 and 2. Superposed epoch analysis revealed that during ~40 min before unloading, both groups demonstrate almost identical plasma sheet thinning and Bz decrease at Geotail. By the sudden unloading time, both groups have nearly identical Bz values in the midtail as well as at 6.6 RE. We conclude that pre‐onset midtail configuration changes are common for all substorm types irrespective of flux growth.
Micro Calorimetric Measurements of Stabilized and Unstabilized Polypropylene Under Wet and Dry Conditions
Authors: Liland Knut Brede , Hvidsten Sverre , Øysæd Harry
Published: January 2014

Isothermal microcalorimetry (MC) was used to study the oxidation stability of isotactic polypropylene (PP) including different concentrations of stabilizer in the temperature range of 110°C–130°C. A microcalorimeter provides in this context a fast method for the investigation of oxidation and thermal stability at various conditions opposite to more classical time‐ and labor‐consuming methods. The measurements were performed in both wet and dry environments in sealed stainless steel vials for new and preaged materials. The preaged materials were aged in advance at 110°C and 100% relative humidity to observe the effect of the ageing for the MC measurements. Different material sizes (ground, unground) were also investigated. The results from the MC measurements on preaged material show that stabilized PP produce less heat flow than unstabilized PP in dry atmosphere, and no significant difference between the various levels of stabilized materials are observed as long as the stabilizer is present. This indicates that when stabilizer is present above a certain but so far unknown concentration (50–100 ppm), the oxidation and the following heat flow of the material becomes much weaker compared with the unstabilized materials. Comparison between wet and dry calorimeter measurements in air indicates that the autoxidation of the unstabilized material is more powerful in a wet atmosphere. No significant differences are observed for the stabilized materials. In the material particle size investigation, the heat flow and total energy output seem to be higher for the ground unstabilized materials; no difference is observed for the stabilized material.
3D Hyperbranched Hollow Carbon Nanorod Architectures for High‐Performance Lithium‐Sulfur Batteries
Authors: Chen Shuangqiang , Huang Xiaodan , Liu Hao , Sun Bing , Yeoh Waikong , Li Kefei , Zhang Jinqiang , Wang Guoxiu
Published: January 2014

Lithium‐sulfur batteries have been plagued for a long time by low Coulombic efficiency, fast capacity loss, and poor high rate performance. Here, the synthesis of 3D hyperbranched hollow carbon nanorod encapsulated sulfur nanocomposites as cathode materials for lithium‐sulfur batteries is reported. The sulfur nanocomposite cathodes deliver a high specific capacity of 1378 mAh g‐1 at a 0.1C current rate and exhibit stable cycling performance. The as‐prepared sulfur nanocomposites also achieve excellent high rate capacities and cyclability, such as 990 mAh g‐1 at 1C, 861 mAh g‐1 at 5C, and 663 mAh g‐1 at 10C, extending to more than 500 cycles. The superior electrochemical performance are ascribed to the unique 3D hyperbranched hollow carbon nanorod architectures and high length/radius aspect ratio of the carbon nanorods, which can effectively prevent the dissolution of polysulfides, decrease self‐discharge, and confine the volume expansion on cycling. High capacity, excellent high‐rate performance, and long cycle life render the as‐developed sulfur/carbon nanorod nanocomposites a promising cathode material for lithium‐sulfur batteries.
Clinical characterization and identification of duplication breakpoints in a Japanese family with Xq28 duplication syndrome including MECP2
Authors: Fukushi Daisuke , Yamada Kenichiro , Nomura Noriko , Naiki Misako , Kimura Reiko , Yamada Yasukazu , Kumagai Toshiyuki , Yamaguchi Kumiko , Miyake Yoshishige , Wakamatsu Nobuaki
Published: January 2014

Xq28 duplication syndrome including MECP2 is a neurodevelopmental disorder characterized by axial hypotonia at infancy, severe intellectual disability, developmental delay, mild characteristic facial appearance, epilepsy, regression, and recurrent infections in males. We identified a Japanese family of Xq28 duplications, in which the patients presented with cerebellar ataxia, severe constipation, and small feet, in addition to the common clinical features. The 488‐kb duplication spanned from L1CAM to EMD and contained 17 genes, two pseudo genes, and three microRNA‐coding genes. FISH and nucleotide sequence analyses demonstrated that the duplication was tandem and in a forward orientation, and the duplication breakpoints were located in AluSc at the EMD side, with a 32‐bp deletion, and LTR50 at the L1CAM side, with “tc” and “gc” microhomologies at the duplication breakpoints, respectively. The duplicated segment was completely segregated from the grandmother to the patients. These results suggest that the duplication was generated by fork‐stalling and template‐switching at the AluSc and LTR50 sites. This is the first report to determine the size and nucleotide sequences of the duplicated segments at Xq28 of three generations of a family and provides the genotype–phenotype correlation of the patients harboring the specific duplicated segment. © 2014 Wiley Periodicals, Inc.
Klippel‐Trenaunay syndromein a boy with concomitant ipsilateral overgrowth and undergrowth
Authors: Ruggieri Martino , Pavone Vito , Polizzi Agata , Falsaperla Raffaele , Fichera Marco , Pavone Piero
Published: January 2014

Klippel‐Trenaunay syndrome comprises congenital vascular malformations of the capillary (nevus flammeus), venous (varicosities) or lymphatic systems and disturbed (usually over‐) growth of one or more extremities and adjacent parts of the trunk. In some individuals the affected body area may show reduced rather than increased growth. Such patients have been described inverse Klippel‐Trenaunay syndrome and included within the spectrum of the syndrome. We report on a 3‐year‐old boy with vascular malformation of the nevus flammeus type extending from the right buttock to the sole of the right foot with clinical and radiological evidence of leg varicosities and underlying deficiency of the soft tissues and bone. In addition, he had macrodactyly of the first, second, and third toes with small nails, and cutaneous syndactyly of the second and third toes of the ipsilateral foot. Cranial magnetic resonance imaging showed high signal lesions in the peritrigonal areas with normal spinal images. This mosaic phenotype demonstrates that decreased and increased growth can coexist in the same body area of an individual with Klippel‐Trenaunay syndrome. © 2014 Wiley Periodicals, Inc.
If not Angelman, what is it? a review of Angelman‐like syndromes
Authors: Tan Wen‐Hann , Bird Lynne M. , Thibert Ronald L. , Williams Charles A.
Published: January 2014

Angelman syndrome (AS) is caused by a lack of expression of the maternally inherited UBE3A gene in the brain. However, about 10% of individuals with a clinical diagnosis of AS do not have an identifiable molecular defect. It is likely that most of those individuals have an AS‐like syndrome that is clinically and molecularly distinct from AS. These AS‐like syndromes can be broadly classified into chromosomal microdeletion and microduplication syndromes, and single‐gene disorders. The microdeletion/microduplication syndromes are now easily identified by chromosomal microarray analysis and include Phelan–McDermid syndrome (chromosome 22q13.3 deletion), MBD5 haploinsufficiency syndrome (chromosome 2q23.1 deletion), and KANSL1 haploinsufficiency syndrome (chromosome 17q21.31 deletion). The single‐gene disorders include Pitt–Hopkins syndrome (TCF4), Christianson syndrome (SLC9A6), Mowat–Wilson syndrome (ZEB2), Kleefstra syndrome (EHMT1), and Rett (MECP2) syndrome. They also include disorders due to mutations in HERC2, adenylosuccinase lyase (ADSL), CDKL5, FOXG1, MECP2 (duplications), MEF2C, and ATRX. Although many of these single‐gene disorders can be caused by chromosomal microdeletions resulting in haploinsufficiency of the critical gene, the individual disorders are often caused by intragenic mutations that cannot be detected by chromosomal microarray analysis. We provide an overview of the clinical features of these syndromes, comparing and contrasting them with AS, in the hope that it will help guide clinicians in the diagnostic work‐up of individuals with AS‐like syndromes. © 2014 Wiley Periodicals, Inc.
Mucopolysaccharidosis type IVA: Evidence of primary and secondary central nervous system involvement
Authors: Borlot Felippe , Arantes Paula Ricci , Quaio Caio Robledo , Franco José Francisco da Silva , Lourenço Charles Marques , Gomy Israel , Bertola Debora Romeo , Kim Chong Ae
Published: January 2014

Mucopolysaccharidosis type IVA is a rare lysosomal storage disease caused by a deficiency of N‐acetylgalactosamine 6‐sulfatase. Studies usually focus on skeletal abnormalities and their consequences. This study explores the neurological manifestations in a cohort of mucopolysaccharidosis type IVA patients, with a detailed focus on brain and spinal magnetic resonance imaging (MRI) findings. We performed a cross‐sectional study involving nine patients with a biochemical confirmation of mucopolysaccharidosis type IVA. The protocol consists of a comprehensive clinical examination and brain and spinal cord MRI analysis for all subjects. The mean age was 16.4 years (±5.7) and the mean onset of symptoms was 11.5 months (±6.3). Overall, cognition was spared in all but one patient and motor weakness was a constant finding in all patients. Deep sensation impairment was found in six patients. The brain MRIs showed non‐specific white matter changes in two patients. Other abnormalities such as clival hypoplasia, basilar invagination, and arachnoid cists appeared in seven of the nine patients. Eight patients presented spinal cord compression, and in three of them, two spinal levels were compromised. Odontoid hypoplasia and degenerative features in the neuroaxis were present in all patients. Our experience with mucopolysaccharidosis type IVA patients supports the evidence of central nervous system involvement. We emphasize the importance of regular clinical assessments with complete MRI studies, as an attempt to detect the early signs of spinal cord compression. This evaluation may be especially important before surgical interventions, as occult lesions may become symptomatic and promote postoperative unfavorable outcomes. © 2014 Wiley Periodicals, Inc.
Diethylzinc‐Promoted Synthesis of Trifluromethyl‐Containing Tryptamine Analogues from Indoles and 2‐Trifluromethyl‐N‐(4‐Toluenesulfonyl)‐Aziridine
Authors: Hirotaki Kensuke , Yamada Yasunori , Hanamoto Takeshi
Published: January 2014

Incorporation of fluorine atoms into biologically active organic molecules often causes enhancement of activity, stability, and solubility, as well as reduction of toxicity. Tryptamine derivatives are known for important medicines concerning our mental health. Therefore, fluorinated tryptamine derivatives could be promising medicinal candidates for pharmaceutical chemistry. We have already reported the regioselective ring‐opening reaction of 2‐CF3‐N‐Ts‐aziridine (Ts=4‐toluenesulfonyl) with some nucleophiles. If this ring‐opening reaction proceeds smoothly at the C3 position of indoles, it could provide a solution for the synthesis of CF3‐containing tryptamine analogues. We examined the diethylzinc‐promoted direct C3 alkylation of indoles with 2‐CF3‐N‐Ts‐aziridine under basic conditions. We have developed the synthesis of CF3‐tryptamine from 2‐CF3‐N‐Ts‐aziridines and indoles by using diethylzinc as a base with excellent yields and complete regioselectivity.