bluuebunny/crossref_metadata_2025 huggingface dataset:
Marine parasites as biological tags in South American Atlantic waters, current status and perspectives
Authors: CANTATORE D. M. P. , TIMI J. T.
Published: January 2014

Many marine fisheries in South American Atlantic coasts (SAAC) are threatened by overfishing and under serious risk of collapsing. The SAAC comprises a diversity of environments, possesses a complex oceanography and harbours a vast biodiversity that provide an enormous potential for using parasites as biological tags for fish stock delineation, a prerequisite for the implementation of control and management plans. Here, their use in the SAAC is reviewed. Main evidence is derived from northern Argentine waters, where fish parasite assemblages are dominated by larval helminth species that share a low specificity, long persistence and trophic transmission, parasitizing almost indiscriminately all available fish species. The advantages and constraints of such a combination of characteristics are analysed and recommendations are given for future research. Shifting the focus from fish/parasite populations to communities allows expanding the concept of biological tags from local to regional scales, providing essential information to delineate ecosystem boundaries for host communities. This new concept arose as a powerful tool to help the implementation of ecosystem-based approaches to fisheries management, the new paradigm for fisheries science. Holistic approaches, including parasites as biological tags for stock delineation will render valuable information to help insure fisheries and marine ecosystems against further depletion and collapse.
Beyond Immutability: Sexuality and Constitutive Choice
Authors: Gill Emily R.
Published: January 2014

Advocates for the equality and dignity of LGBT persons often suggest that the immutability of sexual orientation is their strongest argument. I believe that it is a weak one. First, the individual freedom that liberalism accords to people, absent harm to others, as necessary for human flourishing applies to sexuality as well as to other areas of existence. Second, the distinction often made between status and conduct is a false one, and the argument from immutability effectively protects neither. Third, I examine the notion of constitutive choice, arguing that the line between immutability and choice is more complex than many realize. Finally, greater attention to the notion of constitutive choice may broaden liberalism's hospitality to conceptions of the good in ways that better respect human moral agency and autonomy.
XX.—Aristotle, Newton, Einstein
Authors: Whittaker E. T.
Published: January 2014

IT falls to us this year to commemorate the greatest of men of science, Isaac Newton, on the occasion of the three-hundredth anniversary of his birth. The centuries have not dimmed his fame, and the passage of time is unlikely ever to displace him from the supreme position. His discoveries, however—and this is part of their glory—have not persisted unchanged, but in the hands of his successors have been continually unfolding into fresh evolutions. During the eighteenth and nineteenth centuries there was an immense expansion of knowledge, springing directly from his work, and forming ultimately a vast superstructure based on the Newtonian concepts of space, mass, and force. Since 1900 the progress of science has continued, but the development of physics has changed in character: it has become subversive and radical, questioning the traditional assumptions and uprooting the old foundations. In 1915 the Newtonian doctrine of gravitation was superseded by that of Einstein: the divergence between the results of the two theories, so far as concerns the calculation of the movements of the planets, is extremely slight, and indeed, in almost all cases, too small to be detected by observation; but on the question of the essential nature of gravitation, the two conceptions differ completely and are associated with opposite philosophies of the external world. The other great discovery of the present century is the quantum theory, which in its perfected form of quantum-mechanics appeared in 1925: this also is completely irreconcilable with the postulates of Newtonian science.
Robust output feedback control for the trajectory tracking of robotic wheelchairs
Authors: Chocoteco J. A. , Morales R. , Feliu V. , Sira-Ramírez H.
Published: January 2014

This paper addresses the trajectory tracking control problem of robotic wheelchairs in the presence of modeling uncertainties. The controller has been designed using position and angular measurements. A global ultra-model, or simplified model achieved from flatness considerations is proposed first. This model highly reduces the design complexity of the state estimation and the output feedback control tasks since it groups, as an unknown time-varying disturbance, both the combined effects of all uncertain state-dependent (i.e., endogenous) nonlinearities and those of external (i.e., exogenous) perturbation inputs which are present in the input-to-flat output model of the system. An extended linear high-gain observer, or Generalized Proportional Integral (GPI) observer, is then developed for the simultaneous, though approximate, state and disturbance estimation. The proposed feedback controller combines the global ultra-model and the GPI observers to conform an active disturbance rejection, or disturbance accommodation, control scheme. The simulation results presented in the paper show that the proposed method has a very good tracking performance and robustness in the presence of system uncertainties, external disturbances and noisy corruptions.
Nonlinear bilateral teleoperation using extended active observer for force estimation and disturbance suppression
Authors: Chan Linping , Naghdy Fazel , Stirling David , Field Matthew
Published: January 2014

A novel nonlinear teleoperation algorithm for simultaneous inertial parameters and force estimation at the master and slave sides of the teleoperation system is proposed. The scheme, called Extended Active Observer (EAOB), is an extension of the existing active observer. It provides effective force tracking at the master side with accurate position tracking at the slave side in the presence of inertial parameter variation and measurement noise. The proposed method only requires the measurement of robot position, and as a result significantly reduces the difficulty and cost of implementing bilateral teleoperation systems. The approach is described and its stability is analytically verified. The performance of the method is validated through computer simulation and compared with the Nicosia observer-based controller. According to the results, EAOB outperforms the Nicosia observer method and effectively rejects noise.
POINT DECISIONS FOR INTERVAL–IDENTIFIED PARAMETERS
Authors: Song Kyungchul
Published: January 2014

This paper considers a decision maker who prefers to make a point decision when the object of interest is interval-identified with regular bounds. When the bounds are just identified along with known interval length, the local asymptotic minimax decision with respect to a symmetric convex loss function takes an obvious form: an efficient lower bound estimator plus the half of the known interval length. However, when the interval length or any nontrivial upper bound for the length is not known, the minimax approach suffers from triviality because the maximal risk is associated with infinitely long identified intervals. In this case, this paper proposes a local asymptotic minimax regret approach and shows that the midpoint between semiparametrically efficient bound estimators is optimal.
Co-occurring Duchenne muscular dystrophy and hypertrophic cardiomyopathy in an adult with atypical cardiac phenotype
Authors: Tandon Animesh , Taylor Michael D. , Cripe Linda H.
Published: January 2014

We present the case of a 29-year-old man with mutation-positive Duchenne muscular dystrophy and mutation-positive hypertrophic cardiomyopathy. His cardiac phenotype has characteristics of both disorders; he manifests sub-epicardial left ventricular free wall late gadolinium enhancement that is consistent with Duchenne cardiomyopathy, as well as asymmetric ventricular septal hypertrophy, hyperdynamic left ventricular systolic function, and septal mid-myocardial late gadolinium enhancement, which are characteristic of hypertrophic cardiomyopathy.
The radio remnant of Supernova 1987A at high frequencies and high resolution
Authors: Zanardo G. , Staveley-Smith L. , Ng C. -Y. , Gaensler B. M. , Potter T. M. , Manchester R. N. , Tzioumis A. K.
Published: January 2014

As the remnant of Supernova (SN) 1987A has been getting brighter over time, new observations at high frequencies have allowed imaging of the radio emission at unprecedented detail. We present a new radio image at 44 GHz of the supernova remnant (SNR), derived from observations performed with the Australia Telescope Compact Array (ATCA) in 2011. The diffraction-limited image has a resolution of 349×225 mas, which is the highest achieved to date in high-dynamic range images of the SNR. We also present a new image at 18 GHz, also derived from ATCA observations performed in 2011, which is super-resolved to 0″.25. The new 44 and 18 GHz images yield the first high-resolution spectral index map of the remnant. The comparison of the 44 GHz image with contemporaneous X-ray and Hα observations allows further investigations of the nature of the remnant asymmetry and sheds more light into the progenitor hypotheses and SN explosion. In light of simple free-free absorption models, we discuss the likelihood of detecting at 44 GHz the possible emission originating from a pulsar wind nebula (PWN) or a compact source in the centre of the remnant.
Binary Effects on Supernovae
Authors: Podsiadlowski Philipp
Published: January 2014

Here we review how binary interactions affect the final pre-supernova structure of massive stars and the resulting supernova explosions. (1) Binary-induced mass loss and mass accretion determine the final envelope structure, the mass, radius and chemical composition, which are mainly responsible for the supernova appearance and supernova (sub-)type. (2) Mass loss can also drastically change the core evolution and hence the final fate of a star; specifically, around 10 M⊙, it determines whether a star explodes in a supernova or forms a white dwarf, while for larger masses it can dramatically increase the minimum main-sequence mass above which a star is expected to collapse to a black hole. (3) Mass loss before the supernova directly affects the circumstellar medium (CSM) which can affect the supernova spectrum (e.g. account for the IIn phenomenon), produce powerful radio emission and, in extreme cases, lead to a strong interaction with the supernova ejecta and thus strongly modify the lightcurve shape; it may even be responsible for some of the superluminous supernovae that have recently been discovered.
Early Emission of Core-Collapse Supernovae
Authors: Bersten Melina C. , Benvenuto Omar , Nomoto Ken'ichi
Published: January 2014

We present a study of the early UV/Optical emission of the stripped-envelope supernovae based on a one-dimensional, Lagrangian model that solves the hydrodynamics and radiation transport in an expanding ejecta. The models are compared with observations to constrain the physical properties of the progenitor star, such as radius and mixing of radioactive nickel synthesized during the explosion. In particular, we present models for the early emission of the type IIb SN 2011dh and the Type Ib SN 2008D.
CSM-Interacting Stripped-Envelope Supernovae
Authors: Turatto Massimo , Pastorello Andrea
Published: January 2014

Type Ibn supernovae (SNIbn) are a small group of core-collapse events whose ejecta interact with a He-rich and H-deprived circumstellar medium. The explosion of the prototype of this family, SN 2006jc, was heralded by a major stellar eruption two years before its core collapse. This unexpected discovery increased significantly the interest of the astronomical community toward these unusual events. A number of other objects have been included to the SNIbn zoo. In these contribution we review our current knowledge on this rare family of interacting, stripped-envelope supernovae (SE-SNe).
Superluminous Supernovae
Authors: Quimby Robert M.
Published: January 2014

Not long ago the sample of well studied supernovae, which were gathered mostly through targeted surveys, was populated exclusively by events with absolute peak magnitudes fainter than about −20. Modern searches that select supernovae not just from massive hosts but from dwarfs as well have produced a new census with a surprising difference: a significant percentage of supernovae found in these flux limited surveys peak at −21 magnitude or brighter. The energy emitted by these superluminous supernovae in optical light alone rivals the total explosion energy available to typical core collapse supernovae (>1051 erg). This makes superluminous supernovae difficult to explain through standard models. Adding further complexity to this picture are the distinct observational properties of various superluminous supernovae. Some may be powered in part by interactions with a hydrogen-rich, circumstellar material but others appear to lack hydrogen altogether. Some could be powered by large stores of radioactive material, while others fade quickly and have stringent limits on 56-Ni production. In this talk I will discuss the current observational constrains on superluminous supernova and the prospects for revealing their origins.
Supernova Optical Observations and Theory
Authors: Maeda Keiichi , Bersten Melina C. , Moriya Takashi J. , Folatelli Gaston , Nomoto Ken'ichi
Published: January 2014

We review emission processes within the supernova (SN) ejecta. Examples of the application of the theory to observational data are presented. The emission processes and thermal condition within the SN ejecta change as a function of time, and multi-epoch observations are important to obtain comprehensive views. Through the analyses, we can constrain the progenitor radius, compositions as a function of depth, ejecta properties, explosion asymmetry and so on. Multi-frequency follow-up is also important, including radio synchrotron emissions and the inverse Compton effect, γ-ray emissions from radioactive decay of newly synthesized materials. The optical data are essential to make the best use of the multi-frequency data.
Distance determination to six nearby galaxies using type IIP supernovae.
Authors: Bose Subhash , Kumar Brijesh
Published: January 2014

We use early optical photometric and spectroscopic data of six Type-IIP SNe to derive distances to their host galaxies using the expanding photosphere method (EPM). Our sample consists of luminous to sub-luminous SNe 1999gi, 2004et, 2005cs, 2008in, 2009md and 2012aw; having absolute V-magnitudes from -17 to -15 and host galaxy distances from 5 to 22 Mpc. The SN 2008in is peculiar in nature showing dual behavior of a luminous as well as sub-luminous event. The EPM distances for four of the events in our sample are derived for the first time. We take utmost care in minimizing the errors arising from photospheric velocity determination and the broadband filter responses, hence leaving out uncertainty in dilution factor models as the only major source of error. Our preliminary results indicate that EPM-derived distances using Dessart model is found to be consistent with the distances quoted in the literature. We find that EPM method is applicable only to the early (<50 d) photometric data of supernovae and dense spectroscopic data is necessary to estimate accurate distances.
A tale of two shocks in SN 2004dj
Authors: Ray Alak , Chakraborti Sayan , Yadav Naveen , Smith Randall , Chandra Poonam , Pooley David
Published: January 2014

Type IIP SNe constitute a major fraction of all core-collapse supernovae and arise from massive stars that end their lives close to Red Supergiants. The blastwave from the SN interacting with the progenitor's circumstellar matter produces a hot region bounded by a forward and a reverse shock from which most of the X-ray emission originates. Analysis of archival Chandra observations of SN 2004dj, one of the nearest supernovae since SN 1987A, together with published data from radio and optical bands determines the pre-explosion mass-loss rate, blastwave speed, electron acceleration and magnetic field amplification efficiencies. X-ray emission arises from both inverse Compton scattering by non-thermal electrons accelerated in the forward shock and from thermal emission from the supernova ejecta hit by the reverse shock. Determination of the properties of the radiating plasma based on the separation of thermal and non-thermal radiation differentiates different types of supernovae and their environments.
Light Echoes of Historic Transients
Authors: Rest Armin , Sinnott B. , Welch D. L. , Prieto J. L. , Bianco F.
Published: January 2014

Light echoes, light from a variable source scattered off dust, have been observed for over a century. The recent discovery of light echoes around centuries-old supernovae in the Milky Way and the Large Magellanic Cloud have allowed the spectroscopic characterization of these events, even without contemporaneous photometry and spectroscopy using modern instrumentation. Here we review the recent scientific advances using light echoes of ancient and historic transients, and focus on our latest work on SN 1987A's and Eta Carinae's light echoes.
Dust Destruction in the Cygnus Loop Supernova Remnant
Authors: Sankrit Ravi , Blair William P. , Raymond John C. , Williams Brian J.
Published: January 2014

The Cygnus Loop supernova remnant serves as an excellent laboratory for the study of radiative and non-radiative shocks with speeds in the 150–450 km s−1 range. We present results on shock-excited emission and dust destruction based on Spitzer Space Telescope observations of two well-studied regions in the remnant, (i) a non-radiative shock filament along the NE limb, and (ii) the XA region, characterized by emission from bright radiative shocks.
An Integral View of Balmer-dominated Shocks in Supernova Remnants
Authors: Nikolić Sladjana , van de Ven Glenn , Heng Kevin , Kupko Daniel , Lopez Aguerri Jose Alfonso , Méndez-Abreu Jairo , Serra Joan Font , Beckman John
Published: January 2014

We present integral-field spectroscopic observations with the VIMOS-IFU at the VLT of fast (2000-3000 kms−1) Balmer-dominated shocks surrounding the northwestern rim of the remnant of supernova 1006. The high spatial and spectral resolution of the instrument enable us to show that the physical characteristics of the shocks exhibit a strong spatial variation over few atomic scale lengths across 133 sky locations. Our results point to the presence of a population of non-thermal protons (10-100 keV) which might well be the seed particles for generating high-energy cosmic rays. We also present observations of Tycho's supernova remnant taken with the narrow-band tunable filter imager OSIRIS at the GTC and the Fabry-Perot interferometer GHaFaS at the WHT to resolve respectively the broad and narrow Hα lines across a large part of the remnant.
Molecular Environments of Supernova Remnants
Authors: Chen Yang , Jiang Bing , Zhou Ping , Su Yang , Zhou Xin , Li Hui , Zhang Xiao
Published: January 2014

There are about 70 Galactic supernova remnants (SNRs) that are now confirmed or suggested to be in physical contact with molecular clouds (MCs) with six kinds of evidence of multiwavelength observations. Recent detailed CO-line spectroscopic mappings of a series of SNRs reveal them to be in cavities of molecular gas, implying the roles the progenitors may have played. We predict a linear correlation between the wind bubble sizes of main-sequence OB stars in a molecular environment and the stellar masses and discuss its implication for supernova progenitors. The molecular environments of SNRs can serve as a good probe for the γ-rays arising from the hadronic interaction of the accelerated protons, and this paper also discusses the γ-ray emission from MCs illuminated by diffusive protons that escape from SNR shocks.
The molecular emission from old supernova remnants
Authors: Gusdorf A. , Güsten R. , Anderl S. , Hezareh T. , Wiesemeyer H.
Published: January 2014

Supernovae constitute a critical source of energy input to the interstellar medium (ISM). In this short review, we focus on their latest phase of evolution, the supernova remnants (SNRs). We present observations of three old SNRs that have reached the phase where they interact with the ambient interstellar medium: W28, IC443, and 3C391. We show that such objects make up clean laboratories to constrain the physical and chemical processes at work in molecular shock environments. Our studies subsequently allow us to quantify the impact of SNRs on their environment in terms of mass, momentum, and energy dissipation. In turn, their contribution to the energy balance of galaxies can be assessed. Their potential to trigger a further generation of star formation can also be investigated. Finally, our studies provide strong support for the interpretation of γ-ray emission in SNRs, a crucial step to answer questions related to cosmic rays population and acceleration.
SRAO CO Observation of Supernova Remnants in l = 70° to 190°
Authors: Jeong Il-Gyo , Koo Bon-Chul
Published: January 2014

We present the results 12CO J = 1–0 line observations of eleven Galactic supernova remnants (SNRs) between l = 70° and 190° obtained using the Seoul Radio Astronomy Observatory (SRAO) 6-m radio telescope. We detected CO emission towards most of the remnants. In seven SNRs, molecular clouds show a good spatial relation with their radio morphology: G73.9+0.9, G84.2−0.8, G85.4+0.7, G85.9−0.6, G93.3+6.9 (DA530), 94.0+1.0 (3C 434.1), and G182.4+4.3. Two SNRs are particularly interesting. In G85.4+0.7, there is a filamentary molecular cloud aligned along the south-east boundary of the remnant. This cloud extends to the nearby Hii region G84.9+0.5. If the molecular cloud is associated with both the Hii region and the SNR, the distance to the SNR would be 5–7 kpc. In 3C 434.1, there is a large molecular cloud blocking the western half of the remnant where the radio continuum emission is faint. The cloud shows a very good spatial correlation with radio continuum features, which strongly suggests the physical association of the cloud with the SNR. This gives a distance of 3 kpc to the SNR. We performed 12CO J = 2–1 line observations of this cloud using Kölner Observatorium für Sub-Millimeter Astronomie (KOSMA) 3-m telescope and found a region where the 12CO J = 2–1/1–0 line ratio is high. We present a hydrodynamic model showing that 3C434.1 could have resulted from a SN explosion occurred just outside the boundary of a thin, molecular cloud.
Radio polarization observations of large supernova remnants at λ6 cm
Authors: Han J. L. , Gao X. Y. , Sun X. H. , Reich W. , Xiao L. , Reich P. , Xu J. W. , Shi W. B. , Fürst E. , Wielebinski R.
Published: January 2014

We have observed 79 supernova remnants (SNRs) with the Urumqi 25 m telescope at λ6 cm during the Sino-German λ6 cm polarization survey of the Galactic plane. We measured flux densities of SNRs at λ6 cm, some of which are the first ever measured or the measurements at the highest frequency, so that we can determine or improve spectra of SNRs. Our observations have ruled out spectral breaks or spectral flattening that were suggested for a few SNRs, and confirmed the spectral break of S147. By combining our λ6 cm maps with λ11 cm and λ21 cm maps from the Effelsberg 100 m telescope, we calculated the spectral index maps of several large SNRs. For many remnants we obtained for the first time polarization images, which show the intrinsic magnetic field structures at λ6 cm. We disapproved three objects as being SNRs, OA184, G192.8−1.1 and G16.8−1.1, which show a thermal spectrum and no polarization. We have discovered two large supernova remnants, G178.2−4.2 and G25.1−2.3., in the survey maps.
What Shapes Supernova Remnants?
Authors: Lopez Laura A.
Published: January 2014

Evidence has mounted that Type Ia and core-collapse (CC) supernovae (SNe) can have substantial deviations from spherical symmetry; one such piece of evidence is the complex morphologies of supernova remnants (SNRs). However, the relative role of the explosion geometry and the environment in shaping SNRs remains an outstanding question. Recently, we have developed techniques to quantify the morphologies of SNRs, and we have applied these methods to the extensive X-ray and infrared archival images available of Milky Way and Magellanic Cloud SNRs. In this proceeding, we highlight some results from these studies, with particular emphasis on SNR asymmetries and whether they arise from “nature” or “nurture”.
Nonthermal X-rays from supernova remnants
Authors: Decourchelle Anne
Published: January 2014

Since the discovery of nonthermal X-rays in the shell-type supernova remnant SN1006 almost 20 years ago, the field has developed considerably, owing significant progress to our understanding of particle acceleration. Key to the characterization of the nonthermal emission is the ability of current satellites, XMM-Newton and Chandra, to perform spatially resolved spectroscopy at a relatively small spatial scale.

In this review, I intend to present the main contributions of the study of nonthermal X-rays from supernova remnants to the understanding of particle acceleration.
Supernovae and the Galactic Ecosystem
Authors: Wang Q. Daniel
Published: January 2014

Supernovae are the dominant source of stellar feedback, which plays an important role in regulating galaxy formation and evolution. While this feedback process is still quite uncertain, it is probably not due to individual supernova remnants as commonly observed. Most supernovae likely take place in low-density, hot gaseous environments, such as superbubbles and galactic bulges, and typically produce no long-lasting bright remnants. I review recent observational and theoretical work on the impact of such supernovae on galaxy ecosystems, particularly on hot gas in superbubbles and galactic spheroids.
Gamma-ray observations of supernova remnants
Authors: Lemoine-Goumard Marianne
Published: January 2014

In the past few years, gamma-ray astronomy has entered a golden age. At TeV energies, only a handful of sources were known a decade ago, but the current generation of ground-based imaging atmospheric Cherenkov telescopes has increased this number to more than one hundred. At GeV energies, the Fermi Gamma-ray Space Telescope has increased the number of known sources by nearly an order of magnitude in its first 2 years of operation. The recent detection and unprecedented morphological studies of gamma-ray emission from shell-type supernova remnants is of great interest, as these analyses are directly linked to the long standing issue of the origin of the cosmic-rays. However, these detections still do not constitute a conclusive proof that supernova remnants accelerate the bulk of Galactic cosmic-rays, mainly due to the difficulty of disentangling the hadronic and leptonic contributions to the observed gamma-ray emission. In the following, I will review the most relevant results of gamma ray astronomy concerning supernova remnants (shell-type and middle-age interacting with molecular clouds).
Interaction of escaping cosmic rays with molecular clouds
Authors: Gabici Stefano
Published: January 2014

The study of the gamma–ray radiation produced by cosmic rays that escape their accelerators is of paramount importance for (at least) two reasons: first, the detection of those gamma–ray photons can serve to identify the sources of cosmic rays and, second, the characteristics of that radiation give us constraints on the way in which cosmic rays propagate in the interstellar medium. This paper reviews the present status of the field.
V-band light-curve morphologies of supernovae type II
Authors: Anderson Joseph P
Published: January 2014

We present an analysis of V-band light-curves morphologies of type II supernovae (SNII). This investigation is achieved through photometry of more than 100 SNe including a first analysis of SNII data obtained by the Carnegie Supernova Project (CSP). We define the important observables and present correlations between SNe absolute magnitudes and light-curve decline rates: we find that brighter SNII tend to have faster declining light-curves at all epochs.
Optical studies of Type IIb SN 2011dh
Authors: Sahu D. K. , Anupama G. C. , Chakradhari N. K.
Published: January 2014

UBVRI photometry and low resolution optical spectroscopy of the type IIb SN 2011dh in M51 are presented, covering the first year after the explosion. The peak absolute magnitude inV-band of −17.12±0.18 mag indicates SN 2011dh to be a normal bright type IIb event. The peak quasi-bolometric luminosity indicates that ~ 0.06 M⊙ of56Ni was synthesized in the explosion. The He I lines were detected in the spectra much before the maximum light inB-band. The nebular spectra of SN 2011dh show a box shaped emission in the red wing of [OI] 6300, 6363 line due to Hα emission excited because of shock-wave interaction. The analysis of the nebular spectra indicates a progenitor with a main sequence mass of 10-15 M⊙.
The Structure of Overionized Plasma in SNR IC 443
Authors: Jiang Bing , Bocchino Fabrizio , Miceli Marco , Troja Eleonora , Chen Yang , Yamaguchi Hiroya
Published: January 2014

During the last few years, overionized (recombining) plasmas were unexpectedly discovered in a few supernova remnants, but the origin is still unclear. In this contribution, we present a preliminary spectroscopic analysis of the X-ray emission from the north central region of IC443, one of the “recombining” remnants. An overionized NEI plasma model can reproduce well the Ly-alpha lines and the recombination edges in the spectrum. The ionization temperatures for the metals Mg, Si and S are much higher than the electron temperatures. which is a strong indication of overionization of these elements. The different spectral features of the recombining plasma are characterized on scales of a few arcmin, such as the increasing trend of the pre-cooling temperature and the ionization time from south to north, which may imply a pre-heating direction.
Near-Infrared Study of Iron Knots in Cassiopeia A Supernova Remnant
Authors: Lee Yong-Hyun , Koo Bon-Chul , Moon Dae-Sik , Burton Michael G.
Published: January 2014

We present the results of near-infrared (NIR) imaging and spectroscopic observations of the Galactic supernova remnant Cassiopeia A (Cas A). Applying the method of Principal Component Analysis to our broadband NIR spectra, we identify a total of 61 NIR emission knots of Cas A and classify them into three groups of distinct spectral characteristics: Helium-rich, Sulfur-rich, and Iron-rich groups. The first and second groups are of the circumstellar and supernova ejecta origin, respectively. The third group, which has enhanced iron emission, is of particular interests since it shows intermediate characteristics between the former two groups. We suggest that the Iron-rich group is knots of swept-up circumstellar medium around the contact discontinuity in Cas A and/or supernova ejecta from deep layers of its progenitor star which have recently encountered a reverse shock in the remnant.
Supernova Remnants in the UWISH2 and UWIFE Surveys
Authors: Lee Yong-Hyun , Koo Bon-Chul , Lee Jae-Joon
Published: January 2014

We report the preliminary results for the detection of H2 and [Fe II] line features around the Galactic supernova remnants (SNRs) from the UWISH2 and UWIFE surveys that cover the first galactic quadrant of 7°<l<65° and |b|<1.3°. By this time, we have found a total of 17 H2-emitting and 14 [Fe II]-emitting SNRs in the coverage, and more than a half of them are detected in both H2 and [Fe II] emissions, which implies that the environment of these SNRs might be complex and composed of multi-phase medium. In this paper, we present our identification strategy and some preliminary results including H2 and [Fe II] luminosity distributions.
Distances of Galactic supernova remnants
Authors: Zhu Hui , Tian Wenwu
Published: January 2014

Supernova remnants (SNRs) play a key role in understanding supernovae explosion mechanisms, exploring the likely sources of Galactic cosmic rays and the chemical enrichment of interstellar medium (ISM). Reliable distance determinations to Galactic SNRs are key to obtain their basic parameters, such as size, age, explosion energy, which helps us to study their environment and interstellar medium. We review the methods to determine the distances to SNRs and highlight the kinematic distance measurement by Hiabsorption and CO emission observations.
Simulations of RS Oph and the CSM in Type Ia Supernovae
Authors: Booth Richard A. , Mohamed Shazrene , Podsiadlowski Philipp
Published: January 2014

Smoothed particle hydrodynamics (SPH) models of the recurrent nova RS Ophiuchi are presented, along with simple models for circumstellar absorption lines. The evolution of the model sodium line is similar to the behaviour in some Type Ia SNe, e.g. SN2006X.
Outer Shock Interaction in Young Core-Collapse SNRs
Authors: Lee Jae-Joon
Published: January 2014

Studying the environments in which core-collapse supernovae (SNe) explode and then subsequently evolve is essential to establish the nature of the mass loss and the explosion of the progenitor star. The spatial structure of the outer shock in young core-collapse SNRs provides an opportunity to study the nature of the medium into which the remnant has been expanding. We present our X-ray study of the outer shocks in young core-collapse SNRs in our Galaxy. For Cas A and G292.0+1.8, we find that both remnants have been likely interacting with dense red supergiant winds. For other remnants with bright thermal X-ray emission from the shell, we suggest that they are interacting with pre-existing circumstellar structure. We discuss the nature of the winds and the progenitor stars.
Radio studies of relativistic SN 2009bb
Authors: Ray Alak , Yadav Naveen , Chakraborti Sayan , Soderberg Alicia , Chandra Poonam
Published: January 2014

A local sub-population of type Ib/c supernovae (stripped envelope SNe) with mildly relativistic outflows have been detected as sub-energetic Gamma Ray Bursts (GRBs) or X-ray Flashes (XRFs) and as radio afterglows without detected GRB counterpart. SN 2009bb belongs to the last class of objects. The long term radio observations with (J)VLA and GMRT of this SN map the dynamics of the relativistic ejecta characteristic of Central Engines associated with GRBs. We present here GMRT observations of this SN from October 2009 onwards.
Clumping of ejecta and accelerated cosmic rays in the evolution of type Ia SNRs
Authors: Orlando S. , Bocchino F. , Miceli M. , Petruk O. , Pumo M. L.
Published: January 2014

We investigate the role played by initial clumping of ejecta and by efficient acceleration of cosmic rays (CRs) in determining the density structure of the post-shock region of a Type Ia supernova remnant (SNR) through detailed 3D MHD modeling. Our model describes the expansion of a SNR through a magnetized interstellar medium (ISM), including the initial clumping of ejecta and the effects on shock dynamics due to back-reaction of accelerated CRs. The model predictions are compared to the observations of SN 1006. We found that the back-reaction of accelerated CRs alone cannot reproduce the observed separation between the forward shock (FS) and the contact discontinuity (CD) unless the energy losses through CR acceleration and escape are very large and independent of the obliquity angle. On the contrary, the clumping of ejecta can naturally reproduce the observed small separation and the occurrence of protrusions observed in SN 1006, even without the need of accelerated CRs. We conclude that FS-CD separation is a probe of the ejecta structure at the time of explosion rather than a probe of the efficiency of CR acceleration in young SNRs.
A Rat Model of Photothrombotic Capsular Infarct with a Marked Motor Deficit: A Behavioral, Histologic, and microPET Study
Authors: Kim Hyung-Sun , Kim Donghyeon , Kim Ra Gyung , Kim Jin-Myung , Chung Euiheon , Neto Pedro R , Lee Min-Cheol , Kim Hyoung-Ihl
Published: January 2014

We present a new method for inducing a circumscribed subcortical capsular infarct (SCI), which imposes a persistent motor impairment in rats. Photothrombotic destruction of the internal capsule (IC) was conducted in Sprague Dawley rats (male; n=38). The motor performance of all animals was assessed using forelimb placing, forelimb use asymmetry, and the single pellet reaching test. On the basis of the degree of motor recovery, rats were subdivided into either the poor recovery group (PRG) or the moderate recovery group (MRG). Imaging assessment of the impact of SCI on brain metabolism was performed using 2-deoxy-2-[18F]-fluoro-D-glucose ([18F]-FDG) microPET (positron emission tomography). Photothrombotic lesioning using low light energy selectively disrupted circumscribed capsular fibers. The MRG showed recovery of motor performance after 1 week, but the PRG showed a persistent motor impairment for >3 weeks. Damage to the posterior limb of the IC (PLIC) is more effective for producing a severe motor deficit. Analysis of PET data revealed decreased regional glucose metabolism in the ipsilesional motor and bilateral sensory cortex and increased metabolism in the contralesional motor cortex and bilateral hippocampus during the early recovery period after SCI. Behavioral, histologic, and functional imaging findings support the usefulness of this novel SCI rat model for investigating motor recovery.
Repeated Mild Traumatic Brain Injury Results in Long-Term White-Matter Disruption
Authors: Donovan Virginia , Kim Claudia , Anugerah Ariana K , Coats Jacqueline S , Oyoyo Udochuwku , Pardo Andrea C , Obenaus Andre
Published: January 2014

Mild traumatic brain injury (mTBI) is an increasing public health concern as repetitive injuries can exacerbate existing neuropathology and result in increased neurologic deficits. In contrast to other models of repeated mTBI (rmTBI), our study focused on long-term white-matter abnormalities after bilateral mTBIs induced 7 days apart. A controlled cortical impact (CCI) was used to induce an initial mTBI to the right cortex of Single and rmTBI Sprague Dawley rats, followed by a second injury to the left cortex of rmTBI animals. Shams received only a craniectomy. Ex vivo diffusion tensor imaging (DTI), transmission electron microscopy (TEM), and histology were performed on the anterior corpus callosum at 60 days after injury. The rmTBI animals showed a significant bilateral increase in radial diffusivity (myelin), while only modest changes in axial diffusivity (axonal) were seen between the groups. Further, the rmTBI group showed an increased g-ratio and axon caliber in addition to myelin sheath abnormalities using TEM. Our DTI results indicate ongoing myelin changes, while the TEM data show continuing axonal changes at 60 days after rmTBI. These data suggest that bilateral rmTBI induced 7 days apart leads to progressive alterations in white matter that are not observed after a single mTBI.
Function of Circle of Willis
Authors: Vrselja Zvonimir , Brkic Hrvoje , Mrdenovic Stefan , Radic Radivoje , Curic Goran
Published: January 2014

Nearly 400 years ago, Thomas Willis described the arterial ring at the base of the brain (the circle of Willis, CW) and recognized it as a compensatory system in the case of arterial occlusion. This theory is still accepted. We present several arguments that via negativa should discard the compensatory theory. (1) Current theory is anthropocentric; it ignores other species and their analog structures. (2) Arterial pathologies are diseases of old age, appearing after gene propagation. (3) According to the current theory, evolution has foresight. (4) Its commonness among animals indicates that it is probably a convergent evolutionary structure. (5) It was observed that communicating arteries are too small for effective blood flow, and (6) missing or hypoplastic in the majority of the population. We infer that CW, under physiologic conditions, serves as a passive pressure dissipating system; without considerable blood flow, pressure is transferred from the high to low pressure end, the latter being another arterial component of CW. Pressure gradient exists because pulse wave and blood flow arrive into the skull through different cerebral arteries asynchronously, due to arterial tree asymmetry. Therefore, CW and its communicating arteries protect cerebral artery and blood–brain barrier from hemodynamic stress.
Incorporating Target Shedding Into a Minimal PBPK–TMDD Model for Monoclonal Antibodies
Authors: Li L , Gardner I , Rose R , Jamei M
Published: January 2014

Shedding of a pharmacological target from cells, giving rise to a soluble target that can also bind therapeutic proteins, is a common phenomenon. In this study, a minimal physiologically based pharmacokinetic model was used to simulate the pharmacokinetics of trastuzumab and the simultaneous binding of the compound to soluble (in blood and tissue interstitial space) and membrane‐bound (in the tissue interstitial space) forms of human epidermal growth factor receptor 2 (HER2). The parameter values describing binding of trastuzumab to HER2 were largely derived from in vitro data, and the effects of varying HER2 levels, the affinity difference between membrane‐bound HER2 and shed antigen, and slow binding kinetics were investigated. The model simulates a sharp decrease in trough drug concentrations at concentrations of soluble target between 500 and 1,000 ng/ml in plasma. This corresponds with the clinical concentration range of soluble target wherein changes in half‐life of trastuzumab have been observed.

CPT Pharmacometrics Syst. Pharmacol. (2014) 3, e96; doi:10.1038/psp.2013.73; published online 29 January 2014
Surface plasmon resonance sensing properties of a 3D nanostructure consisting of aligned nanohole and nanocone arrays
Authors: Najiminaini Mohamadreza , Ertorer Erden , Kaminska Bozena , Mittler Silvia , Carson Jeffrey J. L.
Published: January 2014

Molecular surface plasmon resonance (SPR) sensing is one of the most common applications of an array of periodic nanoholes in a metal film.
A theoretical study on tuning the electronic structures and photophysical properties of newly designed platinum(ii) complexes by adding substituents on functionalized ligands as highly efficient OLED emitters
Authors: Zhang Luqiong , Tian Li , Li Ming , He Rongxing , Shen Wei
Published: January 2014

Adding strong π-accepting and electron-donating groups could stabilize MLCT and improve the photophysical properties in platinum(ii) complexes.
Sr3−3xNa3xSi3O9−1.5x (x = 0.45) as a superior solid oxide-ion electrolyte for intermediate temperature-solid oxide fuel cells
Authors: Wei Tao , Singh Preetam , Gong Yunhui , Goodenough John B. , Huang Yunhui , Huang Kevin
Published: January 2014

A new solid oxide-ion conductor Sr3−3xNa3xSi3O9−1.5x (x = 0.45) exhibits the highest oxide-ion conductivity with the lowest activation energy among all the known chemically stable oxide-ion conductors.
Nanoscale zero-valent iron (nZVI) for the treatment of concentrated Cu(ii) wastewater: a field demonstration
Authors: Li Shaolin , Wang Wei , Yan Weile , Zhang Wei-xian
Published: January 2014

A field demonstration was conducted to assess the feasibility of nanoscale zero-valent iron for the treatment of wastewater containing high levels of Cu(ii).
Nanoscale spatially resolved infrared spectra from single microdroplets
Authors: Müller Thomas , Ruggeri Francesco Simone , Kulik Andrzej J. , Shimanovich Ulyana , Mason Thomas O. , Knowles Tuomas P. J. , Dietler Giovanni
Published: January 2014

We present a method for interfacing microdroplets withex situassays and obtained infrared spectra from the contents of individual droplets.
Concentration-dependent magnetic hyperthermic response of manganese ferrite-loaded ultrasmall graphene oxide nanocomposites
Authors: Peng Erwin , Ding Jun , Xue Jun Min
Published: January 2014

The SAR values of the magnetic nanocomposites increased by approximately two-fold when the concentration was reduced by a factor of 3.
A novel ozone gas sensor based on one-dimensional (1D) α-Ag2WO4 nanostructures
Authors: da Silva Luís F. , Catto Ariadne C. , Avansi Waldir , Cavalcante Laécio S. , Andrés Juan , Aguir Khalifa , Mastelaro Valmor R. , Longo Elson
Published: January 2014

A novel and promising ozone gas sensor based on α-Ag2WO4 rod-like structures is obtained via a microwave-assisted hydrothermal method. The electrical resistance measurements show a good gas sensor performance of nanorods at an operating temperature of 300 °C, especially a fast response and a short recovery time.
Simple, green and high-yield production of single- or few-layer graphene by hydrothermal exfoliation of graphite
Authors: Liu Xiangrong , Zheng Mingtao , Xiao Ke , Xiao Yong , He Chenglong , Dong Hanwu , Lei Bingfu , Liu Yingliang
Published: January 2014

Schematic illustration of hydrothermal exfoliation graphite to produce graphene with intercalant and stabilizer under hydrothermal stirring conditions.
Noble metal nanoparticle@metal oxide core/yolk–shell nanostructures as catalysts: recent progress and perspective
Authors: Li Guodong , Tang Zhiyong
Published: January 2014

We summarize the state-of-the art progress in synthesis and catalytic applications of noble metal nanoparticle@metal oxide core/yolk–shell nanostructures.
Concise and scalable asymmetric synthesis of 5-(1-amino-2,2,2-trifluoroethyl)thiazolo[3,2-b][1,2,4]triazoles
Authors: Mei Haibo , Xiong Yiwen , Xie Chen , Soloshonok Vadim A. , Han Jianlin , Pan Yi
Published: January 2014

An asymmetric Mannich-type reaction between lithium-derived imidazo[2,1-b]thiazoles and CF3-sulfinylimine was reported with good yields and excellent diastereoselectivity (>98 : 2 dr).
Cardanol: a green substitute for aromatic oil as a plasticizer in natural rubber
Authors: Mohapatra Sunita , Nando Golok B.
Published: January 2014

Cardanol grafted natural rubber, prepared at room temperature, is a potential green substitute for carcinogenic aromatic oil plasticized natural rubber.
Structure, mechanics, and binding mode heterogeneity of LEDGF/p75–DNA nucleoprotein complexes revealed by scanning force microscopy
Authors: Vanderlinden Willem , Lipfert Jan , Demeulemeester Jonas , Debyser Zeger , De Feyter Steven
Published: January 2014

SFM imaging reveals that LEDGF/p75 alters the DNA structure and mechanics through bridging, unwinding and the formation of flexible bends.
A greener approach toward gadolinium-based contrast agents
Authors: Gazzi Thais P. , Basso Luiz A. , Santos Diógenes S. , Machado Pablo
Published: January 2014

Herein, a new environmentally friendly synthetic approach for Gd-DTPA, Gd-DOTA and their derivatives has been described using ultrasound energy.
Design of fast low‐power floating high‐voltage level‐shifters
Authors: Lehmann T.
Published: January 2014

What limits performance in some recently published digital floating level‐shifters are identified and a new level‐shifter is proposed to address these limitations. An order‐of‐magnitude reduction in power dissipation compared with the recently published fast high‐voltage level‐shifters is obtained; simulations in a high‐voltage 0.35 μm process show the proposed design is capable of shifting a 2.5 V logic signal up by 17.5 V with a propagation delay of 3 ns and a transition energy of 6 pJ.
700 V ultra‐low on‐resistance DB‐nLDMOS with optimised thermal budget and neck region
Authors: Mao Kun , Qiao Ming , Li Zhaoji , Zhang Bo
Published: January 2014

An ultra‐low Ron,sp 700 V DB‐nLDMOS (dual P‐buried‐layer nLDMOS) which uses 0.35 μm technology and full ion implantation technology is proposed. Experimental results show that with 800 V BVds, Ron,sp is only 10.7 Ω · mm2 which is the lowest value of triple RESURF (REduce SURface Field) LDMOS reported before. This mainly benefits from two aspects. First, thermal budgets of the process are strictly limited after implantation of the Pbury layer. Secondly, device sizes of the neck region are optimised to reduce Ron,sp which also suppress the JFET effect of the triple RESURF LDMOS.