bluuebunny/crossref_metadata_2025 huggingface dataset:
The Possibility of the Kelvin–Helmholtz Instability during Sedimentation of Dust Grains in the Protoplanetary Disk
Authors: Hasegawa Yukihiko , Tsuribe Toru
Published: March 2014

We reexamine the possibility of shear-driven turbulence during the sedimentation of dust grains in the protoplanetary disk. Shear-driven turbulence is expected to occur before the onset of a gravitational instability for the MMSN model. However, according to previous studies that did not account of the growth of dust grains, with a larger abundance of dust grains, the gravitational instability is indicated to occur before shear-driven turbulence. In this paper, the case including dust growth is considered, and it is found that a Kelvin–Helmholtz instability tends to occur before the gravitational instability, even in the case with a large abundance of dust grains. This is different from previous results without the dust growth.
An X-Ray Counterpart of HESS J1427−608 Discovered with Suzaku
Authors: Fujinaga Takahisa , Mori Koji , Bamba Aya , Kimura Shoichi , Dotani Tadayasu , Ozaki Masanobu , Matsuta Keiko , PÜHlhofer Gerd , Uchiyama Hideki , Hiraga Junko S. , Matsumoto Hironori , Terada Yukikatsu
Published: March 2014

We report on the discovery of an X-ray counterpart of the unidentified very high-energy gamma-ray source HESS J1427$-$ 608. In the sky field coincident with HESS J1427$-$ 608, an extended source was found in the 2–8 keV band, and was designated as Suzaku J1427–6051. Its X-ray radial profile has an extension of $ \sigma$$ =$ 0$ .\!\!'$ 9 $ \pm$ 0$ .\!\!'$ 1 if approximated by a Gaussian. The spectrum was well fitted by an absorbed power-law with $ N_{\rm H}$$ =$ (1.1 $ \pm$ 0.3) $ \times$ 10$ ^{23}$ cm$ ^{-2}$ , $ \Gamma$$ =$ 3.1$ ^{+0.6}_{-0.5}$ , and the unabsorbed flux $ F_{\rm X}$$ =$ (9$ ^{+4}_{-2}$ ) $ \times$ 10$ ^{-13}$ erg s$ ^{-1}$ cm$ ^{-2}$ in the 2–10 keV band. Using XMM-Newton archive data, we found seven point sources in the Suzaku source region. However, because their total flux and absorbing column densities are more than an order of magnitude lower than those of Suzaku J1427–6051, we consider that they are unrelated to the Suzaku source. Thus, Suzaku J1427–6051 is considered to be a truly diffuse source and an X-ray counterpart of HESS J1427$-$ 608. The possible nature of HESS J1427$-$ 608 is discussed based on the observational properties.
Discovery of Diffuse Hard X-Ray Emission from the Vicinity of PSR J1648−4611 with Suzaku
Authors: Sakai Michito , Matsumoto Hironori , Haba Yoshito , Kanou Yasufumi , Miyamoto Youhei
Published: March 2014

We observed the pulsar PSR J1648$-$ 4611 with Suzaku. Two X-ray sources, Suzaku J1648$-$ 4610 (Src A) and Suzaku J1648$-$ 4615 (Src B), were found in the field of view. Src A is coincident with the pulsar PSR J1648$-$ 4611, which was also detected by the Fermi Gamma-ray Space Telescope. A hard-band image indicates that Src A is spatially extended. We found point sources in the vicinity of Src A by using a Chandra image of the same region, but the point sources have soft X-ray emission, and cannot explain the hard X-ray emission of Src A. The hard-band spectrum of Src A can be reproduced by a power-law model with a photon index of 2.0$ ^{+0.9}_{-0.7}$ . The X-ray flux in the 2–10 keV band is 1.4 $ \times$ 10$ ^{-13}$ erg cm$ ^{-2}$ s$ ^{-1}$ . The diffuse emission suggests a pulsar wind nebula around PSR J1648$-$ 4611, but the luminosity of Src A is much larger than that expected from the spin-down luminosity of the pulsar. Parts of the very-high-energy $ \gamma$-ray emission of HESS J1646$-$ 458 may be powered by this pulsar wind nebula driven by PSR J1648$-$ 4611. Src B has soft emission, and its X-ray spectrum can be described by a power-law model with a photon index of 3.0$ ^{+1.4}_{-0.8}$ . The X-ray flux in the 0.4–10 keV band is 6.4 $ \times$ 10$ ^{-14}$ erg s$ ^{-1}$ cm$ ^{-2}$ . No counterpart for Src B has been found in the literature.
Large-Field CO (J = 1→0) Observations of the Starburst Galaxy M 82
Authors: Salak Dragan , Nakai Naomasa , Miyamoto Yusuke , Yamauchi Aya , Tsuru Takeshi G.
Published: March 2014

We present large-field (15.7 $ \times$ 16.9 arcmin$ ^2$ ) CO ($ J$  $ =$ 1$ \rightarrow$ 0) observations of the starburst galaxy M 82, at an angular resolution of 22$ ''$ with the NRO 45-m telescope. The CO emission was detected in the galactic disk, outflow (driven by the galactic wind) up to $ \sim$ 2 kpc above the galactic plane in the halo, and in tidal streams. The kinematics of the outflow (including CO line splitting) suggests that it has the shape of a cylinder that is diverging outwards. The mass and kinetic energy of the molecular gas outflow are estimated to be (0.26–1.0) $ \times$ 10$ ^{9}\ M_{\odot}$ and (1–4) $ \times$ 10$ ^{56}$ erg. A clump of CO gas was discovered 3.5 kpc above the galactic plane; it coincides with a dark lane previously found in X-ray observations, and a peak in H I emission. A comparison with H I, hot molecular hydrogen and dust suggests that the molecular gas shows signatures of warm and cool components in the outflow and tidal streams, respectively.
Universal Scaling Law in Long Gamma-Ray Bursts
Authors: tsutsui Ryo , shigeyama Toshikazu
Published: March 2014

The overwhelming diversity of long gamma-ray bursts (LGRBs), discovered after the launch of the Swift satellite, is a major obstacle to LGRB studies. Recently, it was shown that the prompt emission of LGRBs can be classified into three subclasses: Type I and Type II LGRBs, populating separate fundamental planes in a 3D space defined by the peak luminosity, the duration, and the spectral peak energy, and outliers belonging to none of these planes. Here, we show that Type I LGRBs exhibit different shapes of light curves from that of Type II LGRBs. Furthermore, we demonstrate that this classification has uncovered a new scaling law concerning the light curve of Type II LGRBs, over a span of 8 orders of magnitude ranging from the prompt emission to the late X-ray afterglow one. The scaled light curve has four distinct phases. The first phase has a characteristic time-scale, while the three subsequent phases exhibit power-law behaviors with different exponents. We attempt a new interpretation in terms of the emission from an optically thick fireball propagating in the cricumstellar matter at relativistic speed, and argue that the four observed phases correspond to its hydrodynamical phases. Our classification scheme succeeds in pinning down intrinsic luminosities of Type II LGRBs through the scaling law with a sample of polymorphic GRBs. Further refinements of this scheme and scaling law will make it possible to use a subclass of LGRBs as new standard candles with the same reliability and accuracy as Type Ia supernovae in more distant universe than the light from supernovae can reach.
On the Origin of Orbital Period Change in WY Cancri: A Genuine Angular-Momentum Loss?
Authors: Chen Wen-Cong
Published: March 2014

WY Cnc is a short-period ($ P$$ =$ 0.829 d) eclipsing RS Canum Venaticorum star, and both components are of the late-type stars. Recently, observations provided by photometric observations and light-time minima show that the orbital period of WY Cnc is experiencing a secular decrease at a rate of $ {d}P/{d}t$$ =$$-$ 1.2 $ \times$ 10$ ^{-7}$ d yr$ ^{-1}$ . In this letter, we consider whether the period change of WY Cnc can originate from angular-momentum loss. In calculations, we assumed that this source has a high wind loss rate of $ \sim$ 10$ ^{-10}$$ M_{\odot}$ yr$ ^{-1}$ . To account for the observation, magnetic braking demands a strong surface magnetic field of $ \gtrsim$ 10000 G, like that of Ap/Bp stars. Furthermore, if this source is perhaps surrounded by a circumbinary disk, and 6% of the wind loss feeds the disk, the tidal torque between the disk and the binary can account for the observed angular-momentum loss rate. Such a strong magnetic field, or an extremely high wind input fraction, seems to be highly unlikely.
Stellar Spectral Subclass Classification Based on Locally Linear Embedding
Authors: Yude Bu , Jingchang Pan , Bin Jiang , Peng Wei
Published: March 2014

Locally linear embedding (LLE) is a recently developed dimension reduction technique. In this paper, we describe how we applied LLE to the stellar subclass classification. We found that LLE classifies the objects with different physical characteristics correctly. We then compared the performance of LLE with that of principal component analysis (PCA) in spectral classification, and found that LLE does better than PCA. We tested the robustness of LLE against the changing of signal-to-noise ratios (SNRs), and found that the performance of LLE is affected by two factors: changing of SNRs and the range of SNRs of the spectra data set. We also studied the variation of LLE parameters, and found that the experiment results are affected by the parameter variation, but not sensitive. Finally, using LLE, we located those objects misclassified by the Sloan Digital Sky Survey pipeline, and estimated its accuracy in classifying stellar subclasses.
Superposition of Cyclotron Lines in Accreting X-Ray Pulsars. II. Increasing B-Field
Authors: Nishimura Osamu
Published: March 2014

Cyclotron lines have been modeled by calculating a superposition of a large number of cyclotron line spectra of photons emerging from different heights of line-forming regions illuminated from above (increasing $B$-field), in addition to ones illuminated from below (decreasing $B$-field), as considered in Paper I (Nishimura 2011, ApJ, 730, 106). This simplified model succeeds to reproduce anharmonic ratios of cyclotron line energies (less than harmonic values), correlations between cyclotron line energies and X-ray intensities observed at different pulse phases, using a line-forming region with increasing $B$-field for the main pulses of Her X-1, Cen X-3, and GX 301$-$ 2. It is also able to reproduce the characteristics of the cyclotron lines in several parts of the secondary pulse of Vela X-1, A 0535$+$ 26, whereas in several parts of both the main and secondary pulses of X 0115$+$ 63. In addition, in the phase-resolved spectra of X 0115$+$ 63, the observed ratios of the centroid energy of the second-harmonic line to the fundamental change from $\sim$ 1.6 to $\sim$ 2.2 with the pulse phase. A combination of the increasing and decreasing $B$-field is able to explain this behavior in terms of the idea that a magnetic-field configuration in a line-forming region can switch from decreasing to increasing $B$-field, and vice versa, as a result of a switch of the primary observed pole, from which the flux mainly comes, with the rotation of the neutron star.
Binary Black Hole Accretion Flows From a Misaligned Circumbinary Disk
Authors: Hayasaki Kimitake , Saito Hideki , Mineshige Shin
Published: March 2014

We studied the basic properties of accretion flows onto binary supermassive black holes, including cases in which a circumbinary disk is misaligned with the binary orbital plane, by means of three-dimensional smoothed particle hydrodynamics simulations. We find that a circular binary system with a misaligned circumbinary disk normally produces a double-peaked mass-accretion-rate variation per binary orbit. This is because each black hole passes across the circumbinary disk plane and captures gas twice in one orbital period. Even in misaligned systems, however, a single peaked mass-accretion-rate variation per binary orbit is produced, if the orbital eccentricity is moderately large ($e \gtrsim$ 0.3). The number of peaks in the mass accretion rates can be understood simply in terms of the orbital phase dependence of the distance between each binary black hole and its closest inner edge of the circumbinary disk. In the cases of eccentric binary black holes having different masses, the less massive black hole can get closer to the circumbinary disk than the massive one, thus tidally splitting gas from its inner edge, but the created gas flows are comparably captured by both black holes with a short time delay. As a consequence, the combined light curve shows periodic occurrence of double-peaked flares with a short interval. This may account for the observed light variations of OJ287.
OAO/MITSuME Photometry of Dwarf Novae. I. SU Ursae Majoris
Authors: Imada Akira , Izumiura Hideyuki , Kuroda Daisuke , Yanagisawa Kenshi , Omodaka Toshihiro , Miyanoshita Ryo , Kawai Nobuyuki , Nogami Daisaku
Published: March 2014

We report on simultaneous $g', R_{\rm c}$, and $I_{\rm c}$ photometry of SU Ursae Majoris during 2011 December–2012 February using OAO/MITSuME. Our photometry revealed that quiescence is divided into three types based on the magnitude and color. Quiescent light curves showed complicated profiles with various amplitudes and time scales. Although no superoutbursts were observed during our run, five normal outbursts occurred with intervals of 11–21 d. The shapes of the normal outbursts were characteristic of the outside-in type. During the rising phase of a normal outburst, the light curve showed periodic modulations with a period of ${\sim}$ 0.048111(354) d, but the origin of this peirod was unclear. We examined daily averaged color–color diagrams, and found that two cycles exist. This implies that the thermal limit cycle in SU UMa is complicated. We newly discovered that $g' - R_{\rm c}$ becomes red about 3 days prior to an outburst. Although the working mechanism on this reddening is unclear, we propose two possibilities: one is that the inner portion of the accretion disk is filled by matter and obscures the central white dwarf; the other is that the stagnation effect works in the outer region of the accretion disk.
X-Ray Observation of the Galactic Supernova Remnant G355.6–0.0 with Suzaku
Authors: Minami Sari , Ota Naomi , Yamauchi Shigeo , Koyama Katsuji
Published: March 2014

We present results of the Galactic supernova remnant (SNR) G355.6–0.0 observed with Suzaku. We resolved diffuse emission detected with ASCA into two objects, G355.6–0.0 and a point-like source, Suzaku J173530–3236. The X-ray emission from G355.6–0.0 exhibits a center-filled morphology within the radio shell. The X-ray spectrum is well-represented by a thin thermal plasma model with enhanced metal abundances. The spatial and spectral properties imply that G355.6–0.0 is a member of the mixed-morphology SNRs. The NH value of ∼6 × 1022 cm-2 supports that G355.6–0.0 is a distant SNR. Suzaku J173530–3236 exhibits a hard X-ray spectrum with a strong Fe emission line, similar to those of cataclysmic variables. The NH value of ∼3 × 1022 cm-2 is smaller than that of G355.6–0.0, and hence Suzaku J173530–3236 is located at the near side of G355.6–0.0.
SSS J122221.7–311523: Double Superoutburst in the Best Candidate for a Period Bouncer
Authors: Kato Taichi , Monard Berto , Hambsch Franz-Josef , Kiyota Seiichiro , Maehara Hiroyuki
Published: March 2014

We observed the 2012–2013 superoutburst of the newly identified transient SSS J122221.7–311523, and found that this object showed two successive superoutbursts. Superhumps grew in amplitude during the second superoutburst, and showed a characteristic feature in their period change reflecting the growth of superhumps. Assuming that the periods of the superhumps in the growing stage [0.07721(1) d] and the post-superoutburst stage [0.07673(3) d] represent the dynamical precession rates at the disk radius of the 3:1 resonance and at the disk radius immediately after the superoutburst, respectively, we found that this object has a very small mass ratio of $q = M_2/M_1 \lt 0.05$. The possible orbital period from quiescent data suggests $q = 0.045$, which is the smallest among mass ratios of hydrogen-rich cataclysmic variables. The long orbital period and low $q$ make this object a perfect candidate for a period bouncer. We suggest that the peculiar feature of the double superoutburst is a result of a low $q$, and may be characteristic of period bouncers.
New Method of Estimating Binary's Mass Ratios by Using Superhumps
Authors: Kato Taichi , Osaki Yoji
Published: March 2014

We propose a new dynamical method of estimating binary's mass ratios by using the period of superhumps in SU UMa-type dwarf novae during the growing stage (the stage A superhumps). This method is based on the working hypothesis that the period of superhumps in the growing stage is determined by the dynamical precession rate at the 3W1 resonance radius, and is suggested in our new interpretation of the superhump period evolution during a superoutburst (2013, PASJ, 65, 95). By comparing objects having known mass ratios, we show that our method can provide sufficiently accurate mass ratios comparable to those obtained by eclipse observations in quiescence. One of the advantages of this method is that it requires neither an eclipse nor any experimental calibration. It is particularly suitable for exploring the low mass-ratio end of the evolution of cataclysmic variables, where the secondary is not detectable by conventional methods. Our analysis suggests that previous determinations of the mass ratio by using superhump periods during a superoutburst were systematically underestimated for low mass-ratio systems, and we provided a new calibration. It reveals that most WZSge-type dwarf novae have either secondaries close to the border of the lower main-sequence or brown dwarfs, and most of the objects have not yet reached the evolutionary stage of period bouncers. Our results are not in contradiction with an assumption that an observed minimum period ($\sim 77$ min) of ordinary hydrogen-rich cataclysmic variables is indeed the minimum period. We highlight how important the early observation of stage A superhumps is, and propose an effective future strategy of observation.
Low-Resolution Spectrum of the Extragalactic Background Light with the AKARI InfraRed Camera
Authors: Tsumura Kohji , Matsumoto Toshio , Matsuura Shuji , Sakon Itsuki , Wada Takehiko
Published: March 2014

The Extragalactic Background Light (EBL) as integrated light from outside of our Galaxy includes information about the early universe and the Dark Ages. We analyzed spectral data of the astrophysical diffuse emission obtained with the low-resolution spectroscopy mode on the AKARI Infra-Red Camera (IRC) in the $1.8-5.3 \mu \textrm m $ wavelength region. Although previous EBL observations in this wavelength region were restricted to observations by DIRBE and IRTS, this study adds a new independent result with negligible contamination of Galactic stars owing to higher sensitivity for point sources. Two other major foreground components, zodiacal light (ZL) and diffuse Galactic light (DGL), were subtracted by taking correlations with ZL brightness estimated by the DIRBE ZL model and with the $100 \mu \textrm m $ dust thermal emission, respectively. The isotropic emission was obtained as EBL, which shows significant excess over integrated light of galaxies at $ \lt 4 \mu \textrm m $. The obtained EBL is consistent with the previous measurements by IRTS and DIRBE.
KIC 7524178—an SU UMa-Type Dwarf Nova Predominantly Showing Negative Superhumps throughout Supercycle
Authors: Kato Taichi , Osaki Yoji
Published: March 2014

We analyzed Kepler long-cadence data of KIC 7524178 (= KIS J192254.92+430905.4), and found that it is an SU UMa-type dwarf nova with frequent normal outbursts. The signal of the negative superhump has always been the dominant one, even during the superoutburst, in contrast to our common knowledge about superhumps in dwarf novae. The signal of the positive superhump was only transiently seen during the superoutburst, and it quickly decayed afterward. The frequency variation of the negative superhump was similar to the two previously studied dwarf novae in the Kepler field, V1504 Cyg and V344 Lyr. This is the first object in which the negative superhumps dominate throughout the supercycle. Nevertheless, the superoutburst was faithfully accompanied by the positive superhump, indicating that the tidal eccentric instability is essential for triggering a superoutburst. All the pieces of evidence strengthen the thermal-tidal instability as being the origin of the superoutburst and supercycle, which makes this object the third example in the Kepler field. This object had an unusually small ($\sim 1.0$ mag) outburst amplitude, and we considered that this object has a high mass-transfer rate close to the thermal-stability limit of the accretion disk. The average periods of the negative and positive superhumps, and the candidate period of the orbital motion were 0.07288 d (variable in the range $0.0723–0.0731$ d), 0.0785 d (variable in the range $0.0772–0.0788$ d), and 0.074606(1) d, respectively
Local Enhancement of the Surface Density in the Protoplanetary Ring Surrounding HD 142527
Authors: Fukagawa Misato , Tsukagoshi Takashi , Momose Munetake , Saigo Kazuya , Ohashi Nagayoshi , Kitamura Yoshimi , Inutsuka Shu-ichiro , Muto Takayuki , Nomura Hideko , Takeuchi Taku , Kobayashi Hiroshi , Hanawa Tomoyuki , Akiyama Eiji , Honda Mitsuhiko , Fujiwara Hideaki , Kataoka Akimasa , Takahashi Sanemichi Z. , Shibai Hiroshi
Published: March 2014

We report on ALMA observations of the dust continuum, and $^{13}\textrm {CO} (J=3-2), \textrm {and} \textrm {C}^{18} \textrm{O} (J=3-2)$ line emission toward a gapped protoplanetary disk around HD 142527. The outer horseshoe-shaped disk shows a strong azimuthal asymmetry in the dust continuum with a ratio of $\sim 30$ to 1 at 336 GHz between the northern peak and the southwestern minimum. In addition, the maximum brightness temperature of 24K at its northern area is exceptionally high at 160 au from a star. To evaluate the surface density in this region, the grain temperature needed constraining, and was estimated from the optically thick $^{13}\textrm {CO} (J=3-2)$ emission. The lower limit of the peak surface density was then calculated to be 28 g cm $^{-2}$ by assuming a canonical gas-to-dust mass ratio of 100. This finding implies that the region is locally too massive to withstand self-gravity, since Toomre's $Q \lesssim 1-2$, and thus it may collapse into a gaseous protoplanet. Another possibility is that the gas mass is low enough to be gravitationally stable, and only dust grains are accumulated. In this case, a lower gas-to-dust ratio by at least 1 order of magnitude is required, implying the possible formation of a rocky planetary core.
A Study of Coronal Holes Observed by SOHO/EIT and the Nobeyama Radioheliograph
Authors: Akiyama Sachiko , Gopalswamy Nat , Yashiro Seiji , Mäkelä Pertti
Published: March 2014

Coronal holes (CHs) are areas of reduced emission in EUV and X-ray images that show bright patches of microwave enhancements (MEs) related to magnetic network junctions inside the CHs. A clear correlation between the CH size and the solar wind (SW) speed is well known, but we have less information about the relationship between MEs and other CH and SW properties. We studied the characteristics of 21 equatorial CHs associated with corotating interaction regions (CIRs) during 1996 to 2005. Our CHs were divided into two groups according to the intensity of the associated geomagnetic storms: Dst≤-100 nT (10 events) and > -100 nT (11 events). Using EUV 284 Å images obtained by SOHO/EIT and 17 GHz microwave images obtained by the Nobeyama Radioheliograph (NoRH), we found a linear correlation not only between the maximum SW speed and the area of EUV CH (r = 0.62), but also between the maximum SW speed and the area of the ME (r = 0.79). We also compared the EUVCH areas with and without an overlapping ME. The area of the CHs with an ME is better correlated with the SW speed (r = 0.71) than the area of those without an ME (r = 0.36). Therefore, the radio ME may play an important role in understanding the origin of SW.
Imaging of the Solar Atmosphere by the Siberian Solar Radio Telescope at 5.7 GHz with an Enhanced Dynamic Range
Authors: Kochanov Alexey A. , Anfinogentov Sergey A. , Prosovetsky Dmitry V. , Rudenko George V. , Grechnev Victor V.
Published: March 2014

The Siberian Solar Radio Telescope (SSRT) is a solar-dedicated directly-imaging interferometer observing the Sun at 5.7 GHz. SSRT has operated in the two-dimensional mode since 1996. The imaging principle of SSRT restricts its opportunities in observations of very bright flare sources, while it is possible to use ‘dirty’ images in studies of low-brightness features, which do not overlap with side lobes from bright sources. The interactive CLEAN technique routinely used for SSRT data provides imaging of active regions, but consumes much time and efforts and does not reveal low-brightness features below the CLEAN threshold. The newly developed technique combines the CLEAN routine with the directly-imaging capability of SSRT, and provides clean images with an enhanced dynamic range automatically. These elaborations considerably extend the range of tasks that can be solved with SSRT. We show here some examples of the present opportunities of SSRT, and compare its data with the images produced by the Nobeyama Radioheliograph at 17 GHz as well as observations in different spectral ranges.
Solar Burst Analysis with 3D Loop Models
Authors: Costa Joaquim Eduardo Rezende , de Aguiar SimõES Paulo José , Pinto Tereza Satiko Nishida , Melnikov Victor Fedorovich
Published: March 2014

A sample of Nobeyama flares was selected and analyzed using a loop model for important flare parameters. The model for the flaring region consists of a three-dimensional dipolar magnetic field, and spatial distributions of nonthermal electrons. We constructed a database by calculating the flare microwave emission for a wide range of these parameters. Out of this database with more than 5000 cases, we extracted general flare properties by comparing the observed and calculated microwave spectra. The analysis of the Nobeyama Radio Polarimeter data was mostly based on the center-to-limb variation of the flare properties with looptop and footpoint electron distributions, and for the Nobeyama Radioheliograph maps on the resultant distribution of emission. One important aspect of this work is a comparison of the analysis of a flare using an inhomogeneous source model and a simplistic homogeneous source model. Our results clearly show that the homogeneous source hypothesis is not appropriate to describe the possible flare geometry, and its use can easily produce misleading results in terms of non-thermal electron density and magnetic field strength. A center darkening of flares was also obtained as a geometrical property of the loop-like sources.
Pentavalent Rotavirus Vaccine in Infants With Surgical Gastrointestinal Disease
Authors: McGrath Eric J. , Thomas Ron , Duggan Christopher , Asmar Basim I.
Published: March 2014

Objectives:

Pentavalent rotavirus vaccine (RV5) has been shown to be well‐tolerated and efficacious in preventing rotavirus gastroenteritis in healthy infants. Safety and immunogenicity of RV5 in infants with surgical gastrointestinal disease have not been studied. The aim of the present study was to evaluate the safety and immunogenicity of RV5 in infants with a history of congenital or acquired intestinal disease requiring resection compared with healthy infants.

Methods:

Infants with intestinal resection were matched by gestational age and chronological age to healthy infants (controls). Dose 1 of RV5 was given at 10 to 12 weeks of chronological age. Doses 2 and 3 were given at intervals of 4 to 10 weeks, with all 3 doses given by 32 weeks. All infants were monitored for adverse events (AEs) by telephone calls, clinic visits, and parental written reports during the first 42 days after each dose and monthly thereafter by telephone for 12 months. Serum anti‐rotavirus immunoglobulin A (IgA) titers were measured prevaccination and 2 weeks after dose 3.

Results:

A total of 5 infants with surgical gastrointestinal disease and 3 control subjects were enrolled. All participants (100%) mounted a 3‐fold increase in serum anti‐rotavirus IgA geometric mean titer postvaccination. RV5 administration to surgical infants was well tolerated with a majority of AEs being attributed to the underlying medical condition.

Conclusions:

Postvaccination serum anti‐rotavirus IgA levels indicate that RV5 is immunogenic in infants with a history of bowel resection, despite varying lengths of residual bowel. RV5 was well tolerated with few vaccine‐related AEs.
Whole‐Exome Sequencing Reveals GPIHBP1 Mutations in Infantile Colitis With Severe Hypertriglyceridemia
Authors: Gonzaga‐Jauregui Claudia , Mir Sabina , Penney Samantha , Jhangiani Shalini , Midgen Craig , Finegold Milton , Muzny Donna M. , Wang Min , Bacino Carlos A. , Gibbs Richard A. , Lupski James R. , Kellermayer Richard , Hanchard Neil A.
Published: March 2014

Severe congenital hypertriglyceridemia (HTG) is a rare disorder caused by mutations in genes affecting lipoprotein lipase (LPL) activity. Here we report a 5‐week‐old Hispanic girl with severe HTG (12,031 mg/dL, normal limit 150 mg/dL) who presented with the unusual combination of lower gastrointestinal bleeding and milky plasma. Initial colonoscopy was consistent with colitis, which resolved with reduction of triglycerides. After negative sequencing of the LPL gene, whole‐exome sequencing revealed novel compound heterozygous mutations in GPIHBP1. Our study broadens the phenotype of GPIHBP1‐associated HTG, reinforces the effectiveness of whole‐exome sequencing in Mendelian diagnoses, and implicates triglycerides in gastrointestinal mucosal injury.
Building community disaster resilience through a virtual community of practice (VCOP)
Authors: Ann Amaratunga Carol
Published: March 2014

Purpose

– This paper aims to discuss a pilot in-progress project to promote community-based research (CBR) as a tool for disaster resilience planning in rural, remote and coastal communities. Using trans-disciplinary approaches, this project demonstrates how emergency and foresight planning in five rural Canadian pilot communities can be enhanced through the co-design of a pilot Web 2.0 “virtual community of practice” (VCOP).

Design/methodology/approach

– The VCOP initiative was designed with pilot and field site communities to facilitate knowledge generation and exchange and to enhance community resilience. Building a culturally appropriate disaster resilience process is an iterative “process of discovery” and community engagement. Through CBR the project supports practitioners and volunteers to share promising practices and lessons-learned for disaster resilience planning.

Findings

– The VCOP is being developed in five rural, remote, coastal pilot sites across Canada. Additional field site work is also underway in three urban centres sponsored by a project partner. This paper provides an overview of the initial concept, design and “proof of concept” work currently underway. The pilot project will end in the Fall 2012.

Research limitations/implications

– Inspired by the work of American adult educator Etienne Wenger, the VCOP entails co-design and co-ownership of a knowledge engagement process; one which enables local “thought leaders” to participate in emergency planning, preparedness, response and recovery. The VCOP provides a communication platform and fosters “foresight” planning and “education for critical awareness”. Through the sharing of theory and practice, i.e. praxis, communities are mobilized and empowered to anticipate future risks and threats and plan for resilient recovery.

Practical implications

– The VCOP foresight planning paradigm challenges the status quo design and delivery of emergency management protocols from traditional “centres of knowledge and power”, e.g. governments and universities and fosters “bottom-up” community-driven planning to anticipate risks and threats and help enhance local capacity for resilient disaster recovery.

Originality/value

– The novel application of a VCOP to disaster emergency planning is in keeping with the spirit and principles of UNISDR's Hyogo Framework for Action 2005-2015. VCOP has potential to demonstrate disaster resilience “foresight” planning as evidenced in the adoption of promising ideas and practices developed by communities, for communities. As Louis Pasteur once said “Chance favours the prepared mind”.
Satisfaction level on quality of life post-earthquake rebuilding
Authors: Mazza Monica , Chiara Pino Maria , Peretti Sara , Scolta Katia , Mazzarelli Enrico
Published: March 2014

Purpose

– In April 2009, a terrible earthquake badly damaged the city of L'Aquila. Several studies have shown that the citizens' ability to react to a stressful situation is related to the satisfaction level of services during the reconstruction process of the city. The general aim of the present study is to investigate whether the knowledge of information about the reconstruction phase has an influence on the satisfaction of the citizens, regarding the lifestyles and the capacity to adapt and respond to changes.

Design/methodology/approach

– Five hundred and three residents in L'Aquila city were interviewed using a questionnaire that examines the satisfaction level, understanding of political issues and the resiliency skills of individuals.

Findings

– The date shows that the lack of information about the work of the facilities of by the government has caused dissatisfaction among the citizens who feel that they have not been well informed about the rebuilding on the city.

Originality/value

– The study can represent an indication concerning the facilities and assistance provided by politicians and be understood as an input in order to improve the administrative system and public welfare.
Urban wetlands and disaster resilience of Colombo, Sri Lanka
Authors: Hettiarachchi Missaka , Athukorale Kusum , Wijekoon Suren , de Alwis Ajith
Published: March 2014

Purpose

– This paper aims to present a long-term research project to understand the nature and extent of degradation in a selected segment of the Colombo Flood Detention Area (CFDA) wetlands. It qualitatively explores the gradual process of change in watersheds and the wetland ecology affecting flood control services, thereby leading to full-blown disasters. It underlines the importance of protecting ecosystem health of urban ecological features for strengthening the disaster resilience of cities.

Design/methodology/approach

– Through analyzing the long-term change of landscape level parameters, water-quality, vegetation and soil quality, the authors emphasize the potential of an outright ecological regime change and the effects on ecosystem services of the wetlands.

Findings

– Colombo is a city surrounded by a large and interconnected system of natural wetlands that provides a valuable flood control service. The rapid and partly ad hoc urbanization in the past 15-25 years has caused a steady degradation in the wetlands that severely threatens the ecosystem services. It was found that the native, grass-dominated marshy habitat of the wetland is rapidly transforming into a habitat with shrubs and small trees (44 percent of the extent). Typical peaty soil in the marsh has also changed into a semi-mineral soil. Both changes result in a significant reduction in water-holding capacity of the wetland, thus increasing the flood frequency.

Practical implications

– These ecological changes have undermined the effectiveness of the repeated cost-intensive engineering measures taken by the authorities to contain floods.

Originality/value

– CFDA had not been studied previously in an ecosystem services and disaster resilience perspectives. The ecological and hydrological aspects have been studied separately without integration.
The influence of enterprisers' green management awareness on green management strategy and organizational performance
Authors: Wu Shwu-Ing , Wu Yu-Chen
Published: March 2014

Purpose

– This study applied the theory of planned behavior (TPB) to examine the awareness of green management among executives in the Top 5000 corporations (as listed in the China Credit Information Service (CCIS)). Perceived risk, perceived benefit, justice, moral obligation, control force, and control beliefs were considered antecedents to the three components of the TPB (attitude, subjective norms and perceived behavior control, PBC). The correlation between intention and implementation of green management strategies was examined, as was the combined influence of these two factors on organizational performance. The paper aims to discuss these issues.

Design/methodology/approach

– 333 valid questionnaires were returned from a sample of the Top 5000 corporations listed in the CCIS. Structural equation modelling was used to verify the causal relationship amongst the green management variables and performance perspectives.

Findings

– The results indicate that perceived risk and perceived benefit have a strong correspondence to the expressed attitudes related to green management strategies; justice and moral obligation are correlated with the subjective norm; control force and control belief are correlated with perceived behavior control (PBC). Working in conjunction, the three components of the TPB exert a strong influence on the intentions of managers and their likelihood of implementing green management strategies. These factors further affect organizational performance.

Practical implications

– When corporations in the service industry are compared with those in the manufacturing industry, the following five paths show significant differences: control force to PBC, control belief to PBC, attitude to strategic intention, subjective norm to strategic intention, and PBC to strategic intention. These results demonstrate that different industry clusters may lead to different path strengths as a corporation adopts green management strategies.

Originality/value

– This study used the TPB to explore green management adoption and was able to clarify the relationship between green management strategies and organizational performance. It is hoped that this study might provide academic as well as practical value.
Mainstreaming sustainability in design education – a capacity building framework
Authors: O'Rafferty Simon , Curtis Hannah , O'Connor Frank
Published: March 2014

Purpose

– The purpose of the paper is to advance the understanding of the role design education plays in sustainable development. It presents a capacity building framework that can be accommodated in various levels of design curriculum development. The framework allows for a macro-view on the key clusters of competencies for ecodesign while allowing for alignment with quantitative and qualitative approaches to evaluation and assessment. The proposed framework does not intend to be universally prescriptive, and it should provide a context for the development bespoke educational programmes and activities.

Design/methodology/approach

– The research utilises a variety of data sources and methods to provide answers to the research questions. Empirical data were collected through the course of a two-year programme of capacity building with design educators in Wales. This two-year programme incorporated a series of workshops and scoping discussions with teaching staff. Additional data were collected through a literature review and best practice scanning. Thus, the research did not follow a linear process. Instead, it was performed according to an iterative process, evolved by interaction between a theoretical foundation (capacity building, ecodesign education) and empirical material (workshops, literature review).

Findings

– Design education may need to situate itself away from the traditional art or engineering setting to facilitate greater interdisciplinary learning. This repositioning of design education will allow for multidisciplinary relationships with other schools and communities such as social science, business or planning. There will be a role for the promotion of international design institutes that provide a more concentrated experience of the value of design and design education.

Research limitations/implications

– This paper sought to explore the context of capacity for sustainable development as it relates to design education. It briefly highlighted some gaps in the literature on capacity building for ecodesign education along with proposing a conceptual framework of key competencies. The intention is to initiate a discussion on the means by which these can be integrated into mainstream design education, lifelong learning and entrepreneurship training.

Originality/value

– There is no similar framework presented in the literature. Much of the research originates from original research conducted with four universities in a unique programme of capacity building. The paper provides the basis for deeper insights into the interdisciplinary perspectives required. This is something the authors hope to report on this year.
Education for sustainable development (ESD)
Authors: Kopnina Helen , Meijers Frans
Published: March 2014

Purpose

– This article aims to explore the challenges posed by the conceptual framework and diversity of practice of education for sustainable development (ESD). The implications of plurality of ESD perspectives and methodological approaches as well variations in ESD practice will be addressed. Critical framework for conceptualizing of ESD which takes environmental ethics into account will be proposed through the discussion of The Ecocentric and Anthropocentric Attitudes Toward the Sustainable Development (EAATSD) scale.

Design/methodology/approach

– The paper opted for a general review approach, covering literature that provides an overview of the concepts and practices of ESD, as well as program evaluation studies. Additionally, qualitative evaluation of EAATSD scale with students of higher professional education was conducted, using in-depth interviews and dialogue with individual students as well as classroom discussions.

Findings

– It was found that there are wide and inconclusive debates about the aims of ESD based on the critique of sustainable development discourse in general and instrumentalism embedded in ESD in particular. According to the qualitative evaluation, EAATSD scale can be used for testing anthropocentric and Ecocentric Attitudes Towards Sustainable Development in students of higher education. Based on these results, this scale was found to be revealing of the critical view of paradoxes and challenges inherent in multiple goals of sustainable development as well as useful for testing anthropocentric and ecocentric attitudes in students of higher education.

Research limitations/implications

– Reliability of the scale needs further statistical testing, and as is the case in conventional EE/ESD evaluations, and consequent research is necessary to improve institutional, national, and international applicability to particular cases. Future research should draw from this critical review in order to devise alternative evaluation tools.

Practical implications

– In practice, this implies that currently administered evaluations of generic ESD, while useful in concrete cultural or institutional settings, might be premature. The article concludes with the reflection upon which conceptual, methodological, cultural, and ethical challenges of ESD which should be useful for ESD researchers and practitioners in different national settings.

Originality/value

– This article fulfills an identified need to address the paradoxes of sustainable development and to study how ESD can be more effective.
Campus sustainability plans in the United States: where, what, and how to evaluate?
Authors: Swearingen White Stacey
Published: March 2014

Purpose

– The purpose of this paper is to describe and analyze the use of integrated campus sustainability plans at US institutions of higher education. The paper also offers a preliminary framework for the evaluation of these plans.

Design/methodology/approach

– The paper examines 27 campus sustainability plans. It determines the types and characteristics of the institutions that have adopted these plans. It then uses content analysis techniques to determine their typical contents and emphases. Finally, the paper draws on literature pertaining to sustainability plans and plan evaluation to present a preliminary tool for evaluating campus sustainability planning efforts.

Findings

– Campus sustainability plans in the USA are extremely diverse. Environmental aspects are most prominent in these plans, and social equity aspects are least prominent. Campus operations receive more attention than do academic or administrative aspects. Most campuses have taken an inclusive, campus-wide approach to developing their sustainability plans. The evaluation of these plans should consider both their process and their substance and should account for circumstances unique to higher education.

Research limitations/implications

– The research is focused on US colleges and universities and may have overlooked some campus sustainability plans that have other titles. Nevertheless, it is a fairly comprehensive analysis of campus sustainability planning efforts to date in the USA.

Practical implications

– Campus sustainability plans are an important integrative tool. Understanding the details and potential evaluation of these plans can help determine their broader adoption and implementation.

Originality/value

– As an emerging tool for campus sustainability efforts, sustainability plans allow colleges and universities to examine operational, academic, and administrative functions in an integrated manner. To date, there has been very little scholarly attention to these plans, and no prior attempt to consider how they might be evaluated.
E-business implementation and performance: analysis of mediating factors
Authors: Lucia-Palacios Laura , Bordonaba-Juste Victoria , Polo-Redondo Yolanda , Grünhagen Marko
Published: March 2014

Purpose

– The purpose of this paper is to examine the impact of e-business implementation (in terms of internal integration and external diffusion) on organizational performance through the mediating effects of differentiation, enterprise agility, customer relationship development and partner attraction.

Design/methodology/approach

– A survey of franchisors was conducted across the USA and Spain. Before running the model, the paper tests for measurement invariance across the two country samples. The paper uses structural equation modeling to test the conceptual model.

Findings

– The results of the measurement invariance suggest that all the constructs supported this characteristic, except for internal integration. External diffusion leads to differentiation, enterprise agility, relationship development and partner attraction for American and Spanish firms. However, internal integration has no impact on any outcome in the USA while, for Spanish firms, it has a positive and direct effect on economic performance. The full mediating role of non-financial performance between external diffusion and organizational performance depends on the country analyzed. While differentiation and relationship development fully mediate this relationship in the US sample, in the Spanish sample, the advantages of external diffusion are transferred through differentiation, enterprise agility and partner attraction.

Practical implications

–The paper suggests that franchise firms should not focus on the direct effect of e-business implementation on performance. Instead, franchisors should consider that its effect on performance is achieved through greater differentiation, relationship development, enterprise agility and partner attraction. So, the paper suggests that franchisors should think about the long-term effects of the advantages obtained from implementing e-business.

Originality/value

– This study contributes to IS research by identifying the link between internal integration and external diffusion and organizational performance through the examination of the mediating role of non-financial performance measures in two countries. Compared with previous research, the paper first analyzes measurement invariance across countries to provide unbiased results.