bluuebunny/crossref_metadata_2025_split huggingface dataset:
On the origin of the helium-rich population in the peculiar globular cluster Omega Centauri
Authors: Romano Donatella , Tosi M. , Cignoni M. , Matteucci F. , Pancino E. , Bellazzini M. 
Published: April 2010

AbstractIn this contribution we discuss the origin of the extreme helium-rich stars which inhabit the blue main sequence (bMS) of the Galactic globular cluster Omega Centauri. In a scenario where the cluster is the surviving remnant of a dwarf galaxy ingested by the Milky Way many Gyr ago, the peculiar chemical composition of the bMS stars can be naturally explained by considering the effects of strong differential galactic winds, which develop owing to multiple supernova explosions in a shallow potential well.
Lithium and beryllium in Population I dwarf stars
Authors: Randich Sofia 
Published: April 2010

AbstractIn the last few years a variety of lithium and beryllium surveys have been carried out among Pop. I stars in the field and open clusters, with the goal to trace the dependence of these element abundances on stellar mass, age, metallicity, and to understand the physical processes that lead to their depletion. I summarize here the most recent results, focusing on stars with temperatures similar to the Sun. In particular, I will discuss Li measurements in solar-type members of old open clusters, which definitively show that the low solar lithium is not the standard for a star of that age and mass.
Lithium in stars with exoplanets
Authors: Israelian Garik 
Published: April 2010

AbstractOur recent study of solar-type stars from the HARPS GTO sample provides highly accurate information with regard to Lithium abundances in stars with and without detected planets (Israelian et al. 2009). When the Li abundances of planet bearing stars are compared with the “single” stars, we find an excess of Li depletion in planet hosts with effective temperatures in the range 5700-5850 K. We also found that small amounts of Li have survived in the atmospheres of some planet-host solar analogs. Enhanced Li depletion in planet host stars puts constraints on mixing processes responsible for this phenomenon. We show that neither age nor metallicity are responsible for this observational fact.
A 3D-NLTE study of the 670 nm solar lithium feature
Authors: Caffau Elisabetta , Ludwig Hans-Günter , Steffen Matthias , Bonifacio Piercarlo 
Published: April 2010

AbstractWe derive the 3D-NLTE lithium abundance in the solar photosphere from the Lii line at 670 nm as measured in several solar atlases. The Li abundance is obtained from line profile fitting with 1D/3D-LTE/3D-NLTE synthetic spectra, considering several possibilities for the atomic parameters of the lines blending the Li feature. The 670 nm spectral region shows considerable differences in the two available disc-centre solar atlases, while the two integrated disc spectra are very similar. We obtain A(Li)3D–NLTE = 1.03. The 1D-LTE abundance is 0.07 dex smaller. The line-lists giving the best fit for the Sun may fail for other stars, while some line-lists fail to reproduce the solar profile satisfactorily. We need a better knowledge of the atomic parameters of the lines blending the Li feature in order to be able to reproduce both the solar spectrum and the spectra of other stars. An improved line-list is also required to derive reliable estimates of the isotopic Li ratio in solar-metallicity stars.
Li-rich giants in the Galactic Bulge. Is Li linked only to evolutionary status?
Authors: Gonzalez Oscar A. 
Published: April 2010

AbstractIn our detailed study of chemical abundances in the Galactic bulge (see Zoccali et al. 2008 for a description of the entire project) we have measured Li abundances by fitting synthetic spectra to the 7Li (6707.18Å) line for ~400 giants in Baade's Window and a field at b=−6 (Gonzalez et al. 2009). We have found 13 stars showing strong 7Li lines in complete contrast to the rest of the sample for which only upper limits could be obtained. Our sample is at least 1.2 mag brighter than the expected RGB bump, therefore we interpreted our results as evidence for stars that might have avoided the observed extra-mixing process or undergoing a Li enrichment process not necessarily linked to the RGB bump.
A very low upper limit for a Be abundance of a carbon-enhanced metal-poor star
Authors: Ito Hiroko , Aoki Wako , Honda Satoshi , Beers Timothy C. , Tominaga Nozomu 
Published: April 2010

AbstractWe performed a 1D LTE chemical abundance analysis of an extremely metal-poor star BD+44°493 ([Fe/H]= −3.7), and set a very low upper limit for its Be abundance: A(Be) < −2.0. It may indicate that the decreasing trend of Be abundances with lower [Fe/H] still holds at [Fe/H] < −3.5, and demonstrate that high C and O abundances do not necessarily imply high Be abundances. However, since the star is a subgiant with Teff ~ 5500K, Be may be depleted.
New results of the spectral observations of CP stars
Authors: Polosukhina N. S. , Shavrina A. V. , Drake N. A. , Kudryavtsev D. O. , Smirnova M. A. 
Published: April 2010

AbstractThe lithium problem in Ap-CP stars has been, for a long time, a subject of debate. Individual characteristics of CP stars, such as high abundance of the rare-earth elements presence of magnetic fields, complicate structure of the surface distribution of chemical elements, rapid oscillations of some CP-stars, make the detection of the lithium lines and the determination of the lithium abundance, a difficult task. During the International Meeting in Slovakia in 1996, the lithium problem in Ap-CP stars was discussed. The results of the Li study carried out in CrAO Polosukhina (1973–1976), the works of Hack & Faraggiana (1963), Wallerstein & Hack (1964), Faraggiana et al. (1992–1996) formed the basis of the International project ‘Lithium in the cool CP-stars with magnetic fields’. The main goal of the project was, using systematical observations of Ap-CP stars with phase rotation in the spectral regions of the resonance doublet Li I 6708 Å and subordinate 6104 Å lithium lines with different telescopes, to create a database, which will permit to explain the physical origin of anomalous Li abundance in the atmospheres of these stars.
Lithium production by thermohaline mixing in low-mass, low-metallicity asymptotic giant branch stars
Authors: Stancliffe Richard J. , Angelou George C. , Lattanzio John C. 
Published: April 2010

AbstractWe examine the effects of thermohaline mixing on the composition of the envelopes of low-metallicity asymptotic giant branch (AGB) stars. We have evolved models of 1, 1.5 and 2M⊙ and of metallicity Z = 10−4 from the pre-main sequence to the end of the thermal pulsing asymptotic giant branch with thermohaline mixing applied throughout the simulations. We find that the small amount of 3He that remains after the first giant branch is enough to drive thermohaline mixing on the AGB and that the mixing is most efficient in the early thermal pulses, with the efficiency dropping from pulse to pulse. We note a surprising increase in the 7Li abundance, with log10ϵ(7Li) reaching values of over 2.5 in the 1.5M⊙ model. It is thus possible to get stars which are both C- and Li-rich at the same time. We compare our models to measurements of carbon and lithium in carbon-enhanced metal-poor stars which have not yet reached the giant branch. These models can simultaneously reproduced the observed C and Li abundances of carbon-enhanced metal-poor turn-off stars that are Li-rich.
Light elements in massive single and binary stars
Authors: Langer N. , Brott I. , Cantiello M. , de Mink S. E. , Izzard R. G. , Yoon S.-C. 
Published: April 2010

AbstractWe highlight the role of the light elements (Li, Be, B) in the evolution of massive single and binary stars, which is largely restricted to a diagnostic value, and foremost so for the element boron. However, we show that the boron surface abundance in massive early type stars contains key information about their foregoing evolution which is not obtainable otherwise. In particular, it allows to constrain internal mixing processes and potential previous mass transfer event for binary stars (even if the companion has disappeared). It may also help solving the mystery of the slowly rotating nitrogen-rich massive main sequence stars.
Boron depletion in 9 to 15 M⊙ stars with rotation
Authors: Frischknecht U. , Hirschi R. , Meynet G. , Ekström S. , Georgy C. , Rauscher T. , Winteler C. , Thielemann F.-K. 
Published: April 2010

AbstractThe treatment of mixing is still one of the major uncertainties in stellar evolution models. One open question is how well the prescriptions for rotational mixing describe the real effects. We tested the mixing prescriptions included in the Geneva stellar evolution code (GENEC) by following the evolution of surface abundances of light isotopes in massive stars, such as boron and nitrogen. We followed 9, 12 and 15 M⊙ models with rotation from the zero age main sequence up to the end of He burning. The calculations show the expected behaviour with faster depletion of boron for faster rotating stars and more massive stars. The mixing at the surface is more efficient than predicted by prescriptions used in other codes and reproduces the majority of observations very well. However two observed stars with strong boron depletion but no nitrogen enrichment still can not be explained and let the question open whether additional mixing processes are acting in these massive stars.
Li survey in giant stars : probing non-standard stellar physics
Authors: Lagarde N. , Charbonnel C. , Jasniewicz G. , North P. , Shetrone M. , Hollek J. , Smith V. V. 
Published: April 2010

AbstractLithium has long been known to be a good tracer of non-standard mixing processes occurring in stellar interiors. Here we present the results of a large survey aimed at determining the surface Li abundance in a sample of about 800 giant (RGB and AGB) stars with accurate Hipparcos parallaxes. We compare the observed Li behaviour with that predicted by stellar models including rotation and thermohaline mixing.
Theoretical stellar ΔY/ΔO in the early Universe
Authors: Ekström Sylvia , Meynet Georges , Maeder André , Chiappini Cristina , Georgy Cyril , Hirschi Raphael 
Published: April 2010

AbstractPopulation III stars initiated the chemical enrichment of the Universe. Chemical evolution models seem to favour fast rotators among the very low-metallicity population. When a star rotates fast, it ejects significant quantities of He and its nucleosynthesic products are modified compared to the case without rotation. The value of ΔY/ΔO is explored from a theoretical point of view through stellar models of zero- or very low-metallicity.
Lithium, beryllium, and boron production in core-collapse supernovae
Authors: Nakamura Ko , Yoshida Takashi , Shigeyama Toshikazu , Kajino Toshitaka 
Published: April 2010

AbstractType Ic supernova (SN Ic) is the gravitational collapse of a massive star without H and He layers. It propels several solar masses of material to the typical velocity of 10,000 km/s, a very small fraction of the ejecta nearly to the speed of light. We investigate SNe Ic as production sites for the light elements Li, Be, and B, via the neutrino-process and spallations. As massive stars collapse, neutrinos are emitted in large numbers from the central remnants. Some of the neutrinos interact with nuclei in the exploding materials and mainly 7Li and 11B are produced. Subsequently, the ejected materials with very high energy impinge on the interstellar/circumstellar matter and spall into light elements. We find that the ν-process in the current SN Ic model produces a significant amount of 11B, consistent with observations if combined with B isotopes from the following spallation production.
Defining Nation and Religious Minorities in Russia and Turkey: A Comparative Analysis
Authors: Tasch Laman 
Published: April 2010

AbstractMany countries today face the challenges posed by their ethnic and religious diversity. This article comparatively analyzes how defining nation in Russia and Turkey affects what groups constitute religious minorities and what their prospects of integration into the Russian and Turkish societies are. It conceptualizes religious minorities as those religious groups that are excluded from the prevailing and institutionalized definitions of nation. This article studies what role religion, comprising Orthodox Christianity, and Sunni Islam, respectively, has played historically and until nowadays in Russia and Turkey in the definitions of their national identities and what kind of religious minorities each of these definitions created. It argues that a position of religious minorities depends not only on the informal association of national identity of the majority with certain religion, but also on the institutionalized support for the dominant religion by the ruling political forces.
Promoting China‐U.S. Collaboration on Soil and Water Resources: China‐U.S. Workshop on Sustainable Management of Soil and Water Resources; Shenyang, China, 5–8 January 2010
Authors: Zhang Xu‐Dong , Parker Jack 
Published: April 2010

Population growth and rapid urbanization in China have intensified competition for land use, with consequences for agricultural productivity, water use allocation, and soil and water quality. Sustainable management and effective remediation technologies are needed in all regions of China. Similar problems exist in the United States, due, for example, to urban sprawl and pressures to increase biofuel production driven by government subsidy programs. As globally dominant contributors to greenhouse gas emissions, China and the United States also have a mutual interest in understanding their consequences.To discuss current research on soil and water resource sustainability issues and to promote bilateral collaboration in research and graduate education between U.S. and Chinese institutions, a workshop was hosted by the Chinese Academy of Sciences (CAS) Institute of Applied Ecology.
AGU Journals Among Most Cited Publications in Climate Change Research
Authors: Sears Jon 
Published: April 2010

Geophysical Research Letters (GRL) and Journal of Geophysical Research‐Atmospheres (JGR‐D) both ranked among the top 10 of the most highly cited research publications on climate change over the past decade in a recent analysis by sciencewatch.com, an Internet tool published by the Thomson Reuters Web of Science® that tracks trends and performances in basic research. Although Nature and Science—the multidisciplinary heavyweights—led the field, GRL ranked fifth and JGR‐D ranked sixth.The study was conducted by searching the Web of Science® database for terms such as “global warming,” “climate change,” “human impact,” and other key phrases in journal articles published and cited between 1999 and the spring of 2009. The analysis produced over 28,000 papers, from which sciencewatch.com identified the most cited institutions, authors, and journals.
Independent review slated for climate change panel
Authors: Showstack Randy 
Published: April 2010

The InterAcademy Council (IAC) has agreed to conduct an independent review of the processes and procedures followed by the Intergovernmental Panel on Climate Change (IPCC) in preparing its assessment reports. The review was requested by IPCC chair Rajendra Pachauri and United Nations secretary general Ban Ki‐moon following some criticism of IPCC, including the inclusion in IPCC's Fourth Assessment Report (AR4) of non‐peer‐reviewed information about the disappearance of Himalaya glaciers.At a 10 March briefing, Ban noted that there were “a very small number of errors” in AR4 and that the IPCC process needs to ensure “full transparency, accuracy, and objectivity, and minimize the potential for any errors going forward.” Ban added, “The threat posed by climate change is real. Nothing that has been alleged or revealed in the media recently alters the fundamental scientific consensus on climate change, nor does it diminish the unique importance of the IPCC work.”
A Fool's Errand: How Not to Conduct a Research Solicitation
Authors: Schwartz Stephen E. 
Published: April 2010

In early December 2009, I participated in a panel review of proposals submitted to the U.S. Department of Energy's Atmospheric System Research Program in response to a call for proposals from early‐career investigators. Fourteen panel members, each of whom had reviewed four to eight proposals, spent a day discussing and evaluating 28 proposals. Yet all was not what it had seemed.Early‐career research awards, which fund scientists for 5 years at approximately US$150,000 per year, are highly sought by tenure‐track investigators because they provide support for an extended period of time and serve to move young scientists forward in their careers. The concept of such a program is thus much to be lauded. The particular call for proposals for which I served as a reviewer was undertaken as part of the American Recovery and Reinvestment Act, with the objective of promoting useful governmental activity while stimulating the economy.
Jian Receives 2009 F. L. Scarf Award
Authors: Anonymous  
Published: April 2010

Lan Jian has been awarded the AGU F. L. Scarf Award, given annually to recent Ph.D recipients for outstanding dissertation research that contributes directly to solar planetary sciences. Jian's thesis is entitled “Radial evolution of large‐scale solar wind structures.” She was formally presented with the award at the Space Physics and Aeronomy section dinner during the 2009 AGU Fall Meeting, held 14–18 December in San Francisco, Calif.Lan Jian received her B.S. in geophysics from University of Science and Technology of China in 2003. She received her M.S. and Ph.D. degrees in geophysics and space physics, under the supervision of Christopher T. Russell, at University of California, Los Angeles in 2006 and 2008, respectively.
Innovative moments and poor outcome in narrative therapy
Authors: Santos Anita , Gonçalves Miguel M. , Matos Marlene 
Published: April 2010

AbstractAims: To analyse a poor outcome case of narrative therapy with a woman victim of intimate violence. Method: The Innovative Moments Coding System: version 1 was applied to all sessions to track the innovative moments (i‐moments) in the therapeutic process. I–moments are the narrative details that occur in psychotherapeutic conversations that are outside the influence of the problematic narrative. This research aims to describe the processes involved in the stability of meanings in psychotherapy through a dialogical approach to meaning making. Findings: Contrarily to what usually occurs in good outcome cases, re‐conceptualization i‐moments are absent. Moreover, two specific types of i‐moments emerged with higher duration: reflection and protest. Qualitative analysis showed that the potential meanings of these i‐moments were surpassed by a return to the problematic narrative. Conclusion: The therapeutic stability seems to be maintained by a systematic return to the problematic narrative after the emergence of novelties. This process was referred from a dialogical perspective as a mutual in‐feeding of voices, one that emerges in the i‐moment and another one that supports the problematic narrative, which is maintained by an oscillation between these two types of voices during therapy.
The autophagy genes atg8 and atg1 affect morphogenesis and pathogenicity in Ustilago maydis
Authors: NADAL MARINA , GOLD SCOTT E. 
Published: April 2010

SUMMARYAutophagy is a complex degradative process in which cytosolic material, including organelles, is randomly sequestered within double‐membrane vesicles termed autophagosomes. In Saccharomyces cerevisiae, the autophagy genes ATG1 and ATG8 are crucial for autophagy induction and autophagosome assembly, respectively, and their deletion has an impact on the autophagic potential of the corresponding mutant strains. We were interested in the role of autophagy in the development and virulence of U. maydis. Using a reverse genetic approach, we showed that the U. maydis ATG8 orthologue, atg8, is associated with autophagy‐dependent processes. Deletion of atg8 abolished autophagosome accumulation in the vacuoles of carbon‐starved cells and drastically reduced the survival of U. maydisΔatg8 mutant strains during these conditions. In addition, atg8 deletion had an impact on the budding process during saprobic haploid growth. The infection of maize with compatible Δatg8 strains resulted in fewer galled plants, and fungal gall colonization was strongly reduced, as reflected by the very low hyphal density in these tissues. Δatg8 infections resulted in the formation of very few teliospores. To corroborate the role of autophagy in U. maydis development, we also deleted the ATG1 orthologue, atg1. Deletion of atg1 yielded phenotypes similar to the Δatg8 strains during saprobic growth, but of lower magnitude. The Δatg1 strains were only slightly less pathogenic than the wild‐type and teliospore production was not affected. Surprisingly, atg1 deletion in the Δatg8 background exacerbated those phenotypes already observed in the Δatg8 and Δatg1 single‐mutant strains, strongly suggesting an additive phenotype. In particular, the double mutant was completely suppressed for plant gall induction.
Targeted biological therapies for Graves’ disease and thyroid‐associated ophthalmopathy. Focus on B‐cell depletion with Rituximab
Authors: Hegedüs Laszlo , Smith Terry J. , Douglas Raymond S. , Nielsen Claus H. 
Published: April 2010

SummaryBased on experience from the treatment of other autoimmune diseases and because of the limitations imposed by existing therapeutic options for Graves’ disease (GD) and thyroid‐associated ophthalmopathy (TAO), rituximab (RTX) was recently proposed as a novel therapy option. Here, we summarize the rationale for using RTX; give an overview of the possible mechanisms of action; and give an account of its effects and side‐effects when used in GD and TAO. Scant evidence, originating from only a few methodologically inhomogeneous studies, suggests that RTX may prolong remission for hyperthyroidism over that seen with antithyroid drugs, at least in mild GD. Furthermore, in patients with TAO, who are unresponsive to conventional immunosuppressive therapy, RTX seems efficacious. As we wait for larger‐scale randomized studies, RTX, should be considered experimental and reserved for patients who do not respond favourably to conventional therapy. It is the first in what is likely to be a series of new and emerging treatments specifically targeting relevant components of the immune system. Further studies will hopefully lead to improved and better tailored, individualized therapy for GD and especially TAO.