bluuebunny/crossref_metadata_2025_split huggingface dataset:
Infrared Tracers of Mass-Loss Histories and Wind-ISM Interactions in
Hot Star Nebulae
Authors: Morris Patrick ,   the Spitzer WRRINGS team
Published: June 2008

AbstractInfrared observations of hot massive stars and their environments provide a
detailed picture of mass loss histories, dust formation, and dynamical
interactions with the local stellar medium that can be unique to the thermal
regime. We have acquired new infrared spectroscopy and imaging with the
sensitive instruments onboard the Spitzer
Space Telescope in guaranteed and open time programs comprised of some of the
best known examples of hot stars with circumstellar nebulae, supplementing with
unpublished Infrared Space Observatory spectroscopy. Here wepresent highlights
of our work on the environment around the extreme P Cygni-type star HDE316285,
providing some defining characteristics of the star's evolution and
interactions with the ISM at unprecented detail in the infrared.
Radiative Feedback in Galaxies
Authors: Oey M. S. , Voges E. S. , Walterbos R. A. M. , Meurer G. R. , Yelda S. , Furst E. 
Published: June 2008

AbstractWe examine the fate of ionizing radiation from massive stars on global scales. First, we compare the observed Hα luminosities of LMC Hii regions with those predicted by the latest generation of stellar atmosphere models. Our results imply that classical Hii regions are on average radiation-bounded, rather than density-bounded, as we found a decade ago. This is likely to necessitate an additional ionizing source for the diffuse, warm ionized medium (WIM) in galaxies. Secondly, we present new results from the SINGG Hα galaxy survey, showing that starburst galaxies have a lower fraction of WIM emission than normal star-forming galaxies. The most intriguing and consequential possible cause for this effect is the escape of ionizing radiation from starbursts. We show that the observations are also consistent with our predictions for the escape of ionizing radiation. Nevertheless, other observations do not necessarily support this scenario and other possible explanations must be considered.
Evidence for a Mass Outflow from Our Galactic Center
Authors: Law Casey 
Published: June 2008

AbstractWe discuss the nature of the Galactic center lobe (GCL), a degree-tall, loop-like structure apparently erupting from the central few hundred parsecs of our Galaxy. Although its coincidence with the Galactic center has inspired diverse models for its origin, the observational evidence connecting this structure to the GC region has been thin. We describe a multiwavelength observing campaign with the VLA, GBT, Spitzer, and other telescopes that finds compelling evidence that the structure is likely formed by a mass outflow from the central tens of parsecs of our Galaxy. The size and mass of the putative outflow is consistent with that expected from the observed supernova rate and gas pressure in the GC region. If the GCL is a mass outflow, its relative proximity offers a unique opportunity for studying these structures in unprecedented detail.
Massive Stars at High Redshifts
Authors: Pettini Max 
Published: June 2008

AbstractThe five years that have passed since the last IAU Symposium devoted to massive stars have seen a veritable explosion of data on the high redshift universe. The tools developed to study massive stars in nearby galaxies are finding increasing application to the analysis of the spectra of star-forming regions at redshifts as high asz= 7. In this brief review, I consider three topics of relevance to this symposium: the determination of the metallicities of galaxies at high redshifts from consideration of their ultraviolet stellar spectra; constraints on the initial mass function of massive stars in galaxies atz= 2 − 3; and new clues to the nucleosynthesis of carbon and nitrogen in massive stars of low metallicity. The review concludes with a look ahead at some of the questions that may occupy us for the next five years (at least!).
Star Forming Galaxies at z > 5
Authors: Taniguchi Yoshi 
Published: June 2008

AbstractWe present recent progress in searching for galaxies at redshift from z ≃ 5 to z ∼ 10. Wide-field and sensitive surveys with 8m class telescopes have been providing more than several hundreds of star forming galaxies at z ∼ 5 − 7 that are probed in the optical window. These galaxies are used to study the early cosmic star formation activity as well as the early structure formation in the universe. Moreover, near infrared deep imaging and spectroscopic surveys have found probable candidates of galaxies from z ∼ 7 to z ∼ 10. Although these candidates are too faint to be identified unambiguously, we human being are now going to the universe beyond 13 billion light years, close to the epoch of first-generations stars; i.e., Population III stars. We also mention about challenges to find Population III-dominated galaxies in the early universe.
Probing the Interstellar Medium and Stellar Environments of Long-Duration GRBs
Authors: Dessauges-Zavadsky Miroslava , Prochaska Jason X. , Chen Hsiao-Wen 
Published: June 2008

AbstractWe review the properties of the gas surrounding high-redshift gamma-ray bursts (GRBs) assessed through the analysis of damped Lyman-alpha systems (DLAs) identified in their afterglow spectra. These GRB-DLAs are characterized by large H I column densities with a median of N(H I) = 1021.7 cm−2, no molecular gas signatures, metallicities ranging from 1/100 to nearly solar with a median exceeding 1/10 solar, and no anomalous abundance patterns. The detection of the atomic Mg lines and the time-variability of the fine-structure lines demonstrates that the majority of the neutral gas along the GRB sightlines is located between 50 pc and a few kpc from the GRB. This implies that this gas is presumably associated with the ambient interstellar medium of the host galaxy and that the derived properties from low-ionization lines do not directly constrain the local environment of the GRB progenitor. The highly ionized gas, traced by N V lines, which could result from a pre-existing H II region produced by the GRB progenitor and neighboring OB stars, appears on the other hand to be very local to the GRB at about 10 pc, yielding a snapshot of the medium's physical conditions at this radius.
The First Stars
Authors: Johnson Jarrett L. , Greif Thomas H. , Bromm Volker 
Published: June 2008

AbstractThe formation of the first generations of stars at redshifts z ≥ 15 − 20 signaled the transition from the simple initial state of the universe to one of ever increasing complexity. We here review recent progress in understanding the assembly process of the first galaxies, starting with cosmological initial conditions and modelling the detailed physics of star formation. In particular, we study the role of HD cooling in ionized primordial gas, the impact of UV radiation produced by the first stars, and the propagation of the supernova blast waves triggered at the end of their brief lives. We conclude by discussing how the chemical abundance patterns observed in extremely low-metallicity stars allow us to probe the properties of the first stars.
Imprint of First Stars Era in the Cosmic Infrared Background Fluctuations
Authors: Kashlinsky Alexander 
Published: June 2008

AbstractWe present the latest results on Cosmic Infrared Background (CIB) fluctuations from early epochs from deep Spitzer data. The results show the existence of significant CIB fluctuations at the IRAC wavelengths (3.6 to 8 μm) which remain after removing galaxies down to very faint levels. These fluctuations must arise from populations with a significant clustering component, but only low levels of the shot noise. There are no correlations between the source-subtracted IRAC maps and the corresponding fields observed with the HST ACS at optical wavelengths. Taken together, these data imply that 1) the sources producing the CIB fluctuations are individually faint with Sν < a few nJy at 3.6 and 4.5 μm; 2) have different clustering pattern than the more recent galaxy populations; 3) are located within the first 0.7 Gyr (unless these fluctuations can somehow be produced by - so far unobserved - local galaxies of extremely low luminosity and with the unusual for local populations clustering pattern), 4) produce contribution to the net CIB flux of at least 1-2 nW m−2 sr−1 at 3.6 and 4.5 μm and must have mass-to-light ratio significantly below the present-day populations, and 5) they have angular density of ~ a few per arcsec2 and are in the confusion of the present day instruments, but can be individually observable with JWST.
The Impact of Extremely Large Telescopes on the Study of the Most
Luminous Stellar Objects
Authors: D'Odorico Sandro 
Published: June 2008

AbstractThe potential advantages of the new generation of Extremely Large Telescopes are
briefly summarized. When used in combination with advanced adaptive optics
modules which can substantially remove the effect of atmospheric turbulence at
infrared wavelengths, these telescopes will provide unique capabilities both in
terms of photon collecting power (→2-4 magnitude advantage) and
angular resolution (4-5 times higher than with current 8-10m telescopes). The
instruments under study for the TMT and E-ELT projects are presented and
compared. I discuss the impact of the ELTs on three major science topics:
stellar populations in galaxies to the Virgo distance, chemical abundances of
the brighter stars in nearby galaxies and high redshift SN and GRBs.
Metallicities at the Sites of Nearby SN and Implications for the SN-GRB Connection
Authors: Modjaz Maryam , Kewley L. , Kirshner R. P. , Stanek K. Z. , Challis P. , Garnavich P. M. , Greene J. E. , Kelly P. L. , Prieto J. L. 
Published: June 2008

AbstractWhile the broad-lined Type Ic supernovae (SN Ic-bl) associated with long-duration gamma-ray bursts (GRBs) have been studied, we do not fully understand the conditions that lead to each kind of explosion in a massive star. Here we show clues as to the production mechanism of GRBs by comparing the chemical abundances at the sites of 5 nearby (z < 0.25) broad-lined SN Ic that accompany nearby GRBs with those of 12 nearby (z < 0.14) broad-lined SN Ic that have no observed GRBs. We show that the oxygen abundances at the GRB sites are systematically lower than those found near ordinary broad-lined SN Ic. A unique feature of this analysis is that we present new spectra of the host galaxies and analyze the measurements of both samples in the same set of ways, using 3 independent metallicity diagnostics. We demonstrate that neither SN selection effects (SN found via targeted vs. non-targeted surveys) nor the choice of strong-line metallicity diagnostic can cause the observed trend. Though our sample size is small, the observations are consistent with the hypothesis that low metal abundance is the cause of some massive stars becoming SN-GRB. We derive a cut-off metallicity of 0.2−0.6 Z⊙, with the exact value depending on the adopted metallicity scale and solar abundance value.
Epigenetic biomarkers in psychiatric disorders
Authors: Peedicayil J 
Published: June 2008

The discovery of biomarkers in psychiatric disorders may help in the diagnosis, prevention and treatment of patients with these disorders. Here, I discuss the potential role of epigenetic biomarkers, that is, epigenetically altered genes and/or expression patterns of proteins or metabolites, in psychiatric disorders. Before epigenetic biomarkers can be clinically applied in these disorders, several issues need to be addressed. These include establishing a connection between biomarkers and the disease process; determining the predictive quality of the biomarkers; determining the effects of disease heterogeneity on the biomarkers; and identifying sample sources for the biomarkers that are easily accessible for testing.British Journal of Pharmacology (2008) 155, 795–796; doi:10.1038/bjp.2008.254; published online 23 June 2008
Raloxifene protects endothelial cell function against oxidative stress
Authors: Wong C M , Yung L M , Leung F P , Tsang S‐Y , Au C L , Chen Z‐Y , Yao X , Cheng C H K , Lau C‐W , Gollasch M , Huang Y 
Published: June 2008

Background and purpose:Maintaining a delicate balance between the generation of nitric oxide (NO) and removal of reactive oxygen species (ROS) within the vascular wall is crucial to the physiological regulation of vascular tone. Increased production of ROS reduces the effect and/or bioavailability of NO, leading to an impaired endothelial function. This study tested the hypothesis that raloxifene, a selective oestrogen receptor modulator, can prevent endothelial dysfunction under oxidative stress.Experimental approach:Changes in isometric tension were measured in rat aortic rings. The content of cyclic GMP in aortic tissue was determined by radioimmunoassay. Phosphorylation of endothelial NOS (eNOS) and Akt was assayed by Western blot analysis.Key results:In rings with endothelium, ACh‐induced relaxations were attenuated by a ROS‐generating reaction (hypoxanthine plus xanthine oxidase, HXXO). The impaired relaxations were ameliorated by acute treatment with raloxifene. HXXO suppressed the ACh‐stimulated increase in cyclic GMP levels; this effect was antagonized by raloxifene. The improved endothelial function by raloxifene was abolished by ICI 182,780, and by wortmannin or LY294002. Raloxifene also protected endothelial cell function against H2O2. Raloxifene increased the phosphorylation of eNOS at Ser‐1177 and Akt at Ser‐473; this effect was blocked by ICI 182,780. Finally, raloxifene was not directly involved in scavenging ROS, and neither inhibited the activity of xanthine oxidase nor stimulated that of superoxide dismutase.Conclusion and implications:Raloxifene is effective against oxidative stress‐induced endothelial dysfunctionin vitrothrough an ICI 182,780‐sensitive mechanism that involves the increased phosphorylation and activity of Akt and eNOS in rat aortae.British Journal of Pharmacology(2008)155, 326–334; doi:10.1038/bjp.2008.262; published online 23 June 2008
The effect of changes in core body temperature on the QT interval in beagle dogs: a previously ignored phenomenon, with a method for correction
Authors: Van Der Linde H J , Van Deuren B , Teisman A , Towart R , Gallacher D J 
Published: June 2008

Background and purpose:Body core temperature (Tc) changes affect the QT interval, but correction for this has not been systematically investigated. It may be important to correct QT intervals for drug‐induced changes in Tc.Experimental approach:Anaesthetized beagle dogs were artificially cooled (34.2 °C) or warmed (42.1 °C). The relationship between corrected QT intervals (QTcV; QT interval corrected according to the Van de Water formula) and Tc was analysed. This relationship was also examined in conscious dogs where Tc was increased by exercise.Key results:When QTcV intervals were plotted against changes in Tc, linear correlations were observed in all individual dogs. The slopes did not significantly differ between cooling (−14.85±2.08) or heating (−13.12±3.46) protocols. We propose a correction formula to compensate for the influence of Tc changes and standardize the QTcV duration to 37.5 °C: QTcVcT (QTcV corrected for changes in core temperature)=QTcV–14 (37.5 – Tc). Furthermore, cooled dogs were re‐warmed (from 34.2 to 40.0 °C) and marked QTcV shortening (−29%) was induced. After Tc correction, using the above formula, this decrease was abolished. In these re‐warmed dogs, we observed significant increases in T‐wave amplitude and in serum [K+] levels. No arrhythmias or increase in pro‐arrhythmic biomarkers were observed. In exercising dogs, the above formula completely compensated QTcV for the temperature increase.Conclusions and implications:This study shows the importance of correcting QTcV intervals for changes in Tc, to avoid misleading interpretations of apparent QTcV interval changes. We recommend that all ICH S7A, conscious animal safety studies should routinely measure core body temperature and correct QTcV appropriately, if body temperature and heart rate changes are observed. British Journal of Pharmacology (2008) 154, 1474–1481; doi:10.1038/bjp.2008.265; published online 23 June 2008
Ischaemia and insulin, but not ischaemia and contraction, act synergistically in stimulating muscle glucose uptake in vivo in humans
Authors: Bosselaar Marlies , Smits Paul , Tack Cees J. 
Published: June 2008

Ischaemia, like muscle contraction, has been reported to induce skeletal muscle glucose uptake in in vitro models. This stimulating effect appears independent of insulin and is probably mediated by activation of AMPK (AMP-activated protein kinase). In the present study, we hypothesized that in vivo in humans ischaemia- and insulin-induced glucose uptake are additive, and that the combined impact of ischaemia and contraction on glucose uptake is of a similar magnitude when each is applied separately. We assessed the effects of ischaemia with and without euglycaemic–hyperinsulinaemia (clamp; protocol 1) and with and without muscle contraction (protocol 2) on muscle FGU (forearm glucose uptake) in healthy subjects. Furthermore, we assessed the impact of ischaemia on FBF (forearm blood flow; plethysmography). In protocol 1, ischaemia increased FGU from 0.6±0.1 at baseline to 5.5±1.9 μmol·min−1·dl−1, and insulin increased FGU to 1.6±0.3 μmol·min−1·dl−1 (P&lt;0.05 for both). The combination of ischaemia+insulin increased FGU to 15.5±2.2 μmol·min−1·dl−1 (P&lt;0.05 compared with each stimulus alone). Maximal FBF obtained after ischaemia was similar with and without hyperinsulinaemia. In protocol 2, isometric contraction increased FGU from 0.3±0.1 to 2.7±0.8 μmol·min−1·dl−1 (P&lt;0.05), but FGU was not significantly different from ischaemia compared with ischaemia+contraction. However, combined ischaemia+contraction resulted in a greater increase in FBF. In summary, ischaemia and insulin independently stimulate skeletal muscle glucose uptake in vivo in humans, whereas ischaemia and contraction do not. The observed differential effects of these stimuli on glucose uptake appear to be unrelated to changes in muscle blood flow.
Expressions of concern and their uses
Authors: NOONAN Bridget M. , PARRISH Debra 
Published: June 2008

ABSTRACTThe rights and responsibilities of journal editors, when allegations of research misconduct are made, are still evolving. One of the issues that editors must consider is whether and how to communicate with their readership after notice that an allegation of research misconduct has been made about a published article. On receiving such notice, some editors have issued an ‘expression of concern’ to inform their readers of a potential problem. This article provides an analysis of the 16 expressions of concern that have been issued, how and when they were issued, and what happened next. Although this tool is relatively new, editors should consider it as part of their armament for ensuring the integrity of the research record during the sometimes lengthy period that misconduct investigations can take, and should develop policies regarding its use.
Is the answer still in the machine: do publishers need digital rights management?
Authors: CALOW Duncan , EGAN Rebecca 
Published: June 2008

ABSTRACTHas the challenge of unauthorized digital reproduction and distribution of copyright works been met by the use of so‐called ‘digital rights management’ (DRM) technology – and what role will DRM play in publishing, including scholarly journal and learned publishing? This article explores the legal and commercial issues surrounding DRM from its analogue origins through to the latest market developments. It argues that the implementation of DRM in other media sectors provides valuable lessons to publishers. Acknowledging the practical challenges that DRM has faced, the article suggests that whilst DRM will offer an answer to ‘the machine', it must form part of a flexible solution that adapts to the requirements of electronic publishing.
Trends in journal prices: an analysis of selected journals, 2000–2006
Authors: CREASER Claire , WHITE Sonya 
Published: June 2008

ABSTRACTThis paper presents summary results from an analysis of the institutional subscription prices for journals in biomedical and social sciences, for a selection of 11 publishers. Overall price, price per page, and price per point of impact factor have been examined for the period 2000–2006. Considerable variation was found between publishers both in their overall levels of price and in the rates of increase observed over the period. There is some evidence that not‐for‐profit publishers may, on average, offer better value for money in terms of price per page and price per point of impact factor, but this is far from conclusive.
Usage statistics for Big Deals: supporting library decision‐making
Authors: BUCKNELL Terry 
Published: June 2008

ABSTRACTOnly simple statistical analysis, using MS Excel and COUNTER‐compliant usage reports, is required to calculate performance metrics for Big Deals. Big Deal e‐fees themselves are a relatively small proportion of journals expenditure, so when budget cuts need to be made, most savings have to be made by cancelling individual journal subscriptions. However, many individual subscriptions are tied by the non‐cancellation clauses that are an inherent part of most Big Deals and so cannot be cancelled unless the Big Deal is cancelled first. Typically, half of all downloaded articles are in the unsubscribed portion of the Big Deal. Thus it is impossible to make even moderate cuts in journals budgets without inflicting serious damage to an institution's access to journal articles, with serious implications on research. Both libraries and publishers benefit from the Big Deal, so it is essential that pricing remains affordable. Libraries may need to educate their funders to ensure that they continue to receive adequate funding for Big Deals.
A Positive Regulatory Role for LjERF1 in the Nodulation Process Is Revealed by Systematic Analysis of Nodule-Associated Transcription Factors of Lotus japonicus
Authors: Asamizu Erika , Shimoda Yoshikazu , Kouchi Hiroshi , Tabata Satoshi , Sato Shusei 
Published: June 2008

Abstract
We have used reverse genetics to identify genes involved in legume-rhizobium symbiosis in Lotus japonicus. We obtained the sequences of 20 putative transcription factors from previously reported large-scale transcriptome data. The transcription factors were classified according to their DNA binding domains and patterns of expression during the nodulation process. We identified two homologues of Medicago truncatula MtHAP2-1, which encodes a CCAAT-binding protein and has been shown to play a role in nodulation. The functions of the remaining genes in the nodulation process have not been reported. Seven genes were found to encode proteins with AP2-EREBP domains, six of which were similar to proteins that have been implicated in ethylene and/or jasmonic acid signal transduction and defense gene regulation in Arabidopsis (Arabidopsis thaliana). We identified a gene, LjERF1, that is most similar to Arabidopsis ERF1, which is up-regulated by ethylene and jasmonic acid and activates downstream defense genes. LjERF1 showed the same pattern of up-regulation in roots as Arabidopsis ERF1. The nodulation phenotype of roots that overexpressed LjERF1 or inhibited LjERF1 expression using an RNA interference construct indicated that this gene functions as a positive regulator of nodulation. We propose that LjERF1 functions as a key regulator of successful infection of L. japonicus by Mesorhizobium loti.