bluuebunny/crossref_metadata_2025_split huggingface dataset:
UBVRI CCD photometric study of southern open star clusters observed at Pico dos Dias Observatory (LNA/Brazil)
Authors: Caetano Thiago Costa , Dias Wilton S. 
Published: January 2010

AbstractOpen clusters have long been recognized as important objects to investigate aspects of Galactic structure such as the location of spiral arms, Galactic dynamics or even the chemical-abundance gradients in the Galactic disk. Great effort has been dedicated to studies of these objects throughout the past few years to determine parameters like age, distance, reddening, metallicity as well as kinematic information in a systematic and consistent manner. In this work, we present results on several open clusters selected from the DAML02 catalog that have been observed and investigated for the first time. CCD UBVRI (Johnsons–Cousins system) observations were carried out in 2009 using the 60 cm telescope of the Pico dos Dias Observatory (LNA/Brazil). The color–color and color–magnitude diagrams were analyzed for each cluster with the help of a program written by our group, which allows handling photometric and astrometric data simultaneously. We determined the fundamental parameters (reddening, distance and age) using the main-sequence fitting method, taking into account kinematic information of individual stars in the clusters. The mean proper motion and radial velocity were estimated using a set of stars selected photometrically.
Investigation of star clusters found in the 2mass catalog
Authors: Glushkova Elena , Yadav Ramakant , Koposov Sergey 
Published: January 2010

AbstractWe have launched a program of UBVR CCD photometric investigations of new clusters detected in the 2mass catalog based on an automatic detection method, which uses a convolution with a density function. Three new clusters, Koposov 12, Koposov 53 and Koposov 77 were observed in UBVI with the 104 cm Sampurnanand telescope located at ARIES, Manora Peak, India. Their ages, distances, color excesses and metallicities have been derived using photometric data.
Constraining star cluster disruption mechanisms
Authors: Konstantopoulos I. S. , Bastian N. , Gieles M. , Lamers H. J. G. L. M. 
Published: January 2010

AbstractStar clusters are found in all sorts of environments, and their formation and evolution is inextricably linked to the star-formation process. Their eventual destruction can result from a number of factors at different times, but the process can be investigated as a whole through the study of cluster age distributions. Observations of populous cluster samples reveal a distribution following a power law of index approximately −1. In this work, we use M33 as a test case to examine the age distribution of an archetypal cluster population and show that it is, in fact, the evolving shape of the mass detection limit that defines this trend. That is to say, any magnitude-limited sample will appear to follow a dN/dτ = τ−1 relation, while cutting the sample according to mass gives rise to a composite structure, perhaps implying a dependence of the cluster disruption process on mass. In the context of this framework, we examine different models of cluster disruption from both theoretical and observational perspectives.
Metallicities of intermediate-age and old star clusters in the Large Magellanic Cloud
Authors: Kučinskas Arūnas , Dobrovolskas Vidas , Černiauskas Algimantas , Lazauskaitė Roma , Tanabé Toshihiko 
Published: January 2010

AbstractWe derive photometric metallicities for 56 intermediate-age and old star clusters in the Large Magellanic Cloud from the slopes of their red-giant branches in near-infrared color–magnitude diagrams (CMDs). The cluster sample covers the LMC bar and disk to a distance of ~2 kpc from the LMC center. The derived cluster metallicity distribution spans a range of [Fe/H] = +0.0 . . . 1.4 and is similar to the metallicity distribution of field stars. We find that the average cluster metallicities in certain fields of the LMC bar and disk may be different, but there seems to be no compelling evidence for a global cluster metallicity gradient in the LMC.
Evolution and appearance of Be stars in SMC clusters
Authors: Martayan C. , Baade D. , Frémat Y. , Zorec J. 
Published: January 2010

AbstractStar clusters are privileged laboratories for studying the evolution of massive stars (OB stars). One particularly interesting question concerns the phases during which the classical Be stars occur, which—unlike HAe/Be stars—are not pre-main-sequence objects, nor supergiants. Rather, they are extremely rapidly rotating B-type stars with a circumstellar decretion disk formed by episodic ejections of matter from the central star. To study the impact of mass, metallicity, and age on the Be phase, we observed Small Magellanic Cloud (SMC) open clusters with two different techniques: (i) with the ESO–WFI in slitless mode, which allowed us to find the brighter Be and other emission-line stars in 84 SMC open clusters, and (ii) with the VLT–FLAMES multifiber spectrograph to determine accurately the evolutionary phases of Be stars in the Be-star-rich SMC open cluster NGC 330. Based on a comparison to the Milky Way, a model of Be stellar evolution, appearance as a function of metallicity and mass, and spectral type is developed, involving the fractional critical rotation rate as a key parameter.
massclean(MASSive CLuster Evolution and ANalysis Package): description, tests, and results
Authors: Popescu Bogdan , Hanson M. M. 
Published: January 2010

Abstractmasscleanis a new, sophisticated and robust stellar cluster image and photometry simulation package. This package can create color–magnitude diagrams and standard FITS images in any of the traditional optical and near-infrared bands based on cluster characteristics input by the user, including but not limited to distance, age, mass, radius and extinction. At the limit of very distant, unresolved clusters, we have checked the integrated colors created inmasscleanagainst those from other simple stellar population models, with consistent results. Because the algorithm populates the cluster with a discrete number of tenable stars, it can be used as part of a Monte Carlo method to derive the probabilistic range of characteristics (integrated colors, for example) consistent with a given cluster mass and age. We present the first ever mass-dependent integrated colors as a function of age, derived from over 100 000 Monte Carlo runs, which can be used to improve the current age-determination methods for stellar clusters.
Hierarchical clustering in the Local Group dwarf galaxy NGC 6822
Authors: Schmeja S. , Gouliermis D. A. , Klessen R. S. , de Blok W. J. G. , Walter F. 
Published: January 2010

AbstractStar formation appears to be clumped into a hierarchy of structures, from giant molecular clouds down to individual cores and clusters, which are often hierarchical themselves, showing significant substructure. This has been demonstrated for our Galaxy through the application of sophisticated statistical methods, in particular the nearest-neighbour density and the minimum spanning tree (MST), to different star-forming regions. Here we present our analysis of clustered star formation as demonstrated through the detection of structures of young stellar populations in the dwarf star-forming galaxy NGC 6822.
Pre-main-sequence stars in the stellar association N 11 in the Large Magellanic Cloud: clustering properties
Authors: Vallenari Antonella , Sordo Rosanna , Chiosi Emanuela 
Published: January 2010

AbstractMagellanic Clouds are of extreme importance to study the star-formation process in low-metallicity environments. Here, we discuss the clustering properties of the pre-main-sequence candidates and young embedded stellar objects in N 11, located in the Large Magellanic Cloud. Deep archival HST/ACS photometry is used to derive color–magnitude diagrams of the associations in N 11 and of the foreground field population. These data are complemented by archival infrared Spitzer data which allow detection of young embedded stellar objects. The spatial distribution of the pre-main-sequence candidates and young embedded stellar objects is discussed. The degree of clustering is derived using the minimal-spanning-tree method. No significant difference is found in clustering degree of young blue main-sequence stars and faint pre-main-sequence candidates, suggesting that they might be part of the same formation process.
Bridging galactic star formation from intermediate to local epochs
Authors: Voyer Elysse N. , de Mello Duilia F. , Gardner Jonathan P. , Siana Brian , Teplitz Harry 
Published: January 2010

AbstractStarburst galaxies trace the star-formation history of the Universe throughout cosmological time. Several studies have shown that the star-formation-rate density of the Universe begins to steadily decline after the Universe had aged ~ 5.8 Gyr (redshifts z ~ 1). However, we do not yet fully understand the mechanism behind this shift in star formation at intermediate z. One possibility is that during this epoch galaxies underwent ‘downsizing,’ a shift in star formation being dominated by high- to lower-mass galaxies. Rest-frame ultraviolet (UV) observations of starburst galaxies reveal regions of young stellar clusters where massive O and B stars dominate the luminosity. Observations in the FUV (~ 1500 Å) can be used to detect starburst galaxies at z < 1 because the bright end of the rest-frame FUV spectrum is not redshifted much, and is observable in the FUV filter. Alternatively, the rest-frame FUV light from starburst galaxies at higher redshifts is shifted to longer wavelengths and must be observed in redder filters. We present a study of the starburst population at intermediate z from FUV data taken with Hubble's Solar Blind Channel (SBC) of the Advanced Camera for Surveys (ACS). The number counts of FUV galaxies as a function of magnitude provide a direct statistical measure of the density and evolution of starbursts, and subsequently of the stellar clusters formed within these galaxies' environments. We present a comparison between the FUV starburst-galaxy counts at this epoch, and the local FUV counts of starbursts observed with GALEX.
Label-free RF biosensors for human cell dielectric spectroscopy
Authors: Dalmay Claire , Pothier Arnaud , Cheray Mathilde , Lalloue Fabrice , Jauberteau Marie-Odile , Blondy Pierre 
Published: January 2010

This paper presents an original biosensor chip allowing determination of intrinsic relative permittivity of biological cells at microwave frequencies. This sensor permits non-invasive cell identification and discrimination using an RF signal to probe intracellular medium of biological samples. Indeed, these sensors use an RF planar resonator that allows detection capabilities on less than 10 cells, thanks to the microscopic size of its sensitive area. Especially, measurements between 15 and 35 GHz show the ability label-free biosensors to differentiate two human cell types using their own electromagnetic characteristics. The real part of permittivity of cells changes from 20 to 48 for the nervous system cell types studied. The proposed biodetection method is detailed and we show how the accuracy and the repeatability of measurements have been improved to reach reproducible measurements.
Optically modulated III–V nitride-based high-power IMPact Avalanche Transit Time oscillator at Millimeter-wave window frequency
Authors: Mukherjee Moumita , Roy Sitesh Kumar 
Published: January 2010

Extensive simulation experiments are carried out for the first time, to study the optical modulation of the high- frequency characteristics of III–V GaN-(gallium nitride) based top-mounted and flip-chip IMPact Avalanche Transit Time (IMPATT) oscillators at MM-wave window frequency (140.0 GHz). It is found that the un-illuminated GaN IMPATT is capable of delivering a RF power of 5.6 W with an efficiency of 23.5% at 145.0 GHz. Frequency up-chirping of 6.0 GHz and a degradation of RF power output by almost 15.0% are further observed in case of photo-illuminated FC IMPATT. The study reveals that compared to predominate electron photocurrent in top-mounted IMPATT, photo-generated leakage current dominated by hole in flip-chip IMPATT has more pronounced effect on the GaN-based device as regards the frequency chirping and decrease of negative conductance and total negative resistance per unit area of the device. The inequality in the magnitudes of electron and hole ionization rates in the wide band gap semiconductor has been found to be correlated with the above results. The study reveals that GaN IMPATT is a potential candidate for replacing conventional IMPATTs at high-frequency operation. These results are useful for practical realization of optically controlled GaN-based high-power IMPATTs for application in MM-wave communication systems.
Measurement of the density of magnetized fusion plasma using microwave reflectometry
Authors: Giacalone Jean-Claude , Sabot Roland , Clairet Frédéric , Bottereau Christine , Molina Diego 
Published: January 2010

About 25 years have elapsed since the first measurement by a FW-CW (called fast sweeping) reflectometer of the electronic density in magnetized fusion plasma. Substituting tube sources with solid-state components has resulted in a decrease of the sweeping time from the millisecond to the microsecond range. Based on voltage control oscillators and on active frequency multipliers, four profile reflectometers covering the range 33–155 GHz are in operation on Tore-Supra tokamak. Their originality is the use of one source for the launched and reference signal, although the detection is heterodyne. Indeed, a single side band modulator shifts the launched frequency ahead of frequency multipliers. With a sweeping time comparable to the plasma turbulence characteristic time the density profile is frozen. The density profile is then reliably measured with high radial and temporal resolution.
Calderas Bottom‐to‐Top: An Online Seminar and Field Trip
Authors: Wilcock Jack , Longpré Marc‐Antoine , De Moor J. Maarten , Ross Jake , Zimmerer Matt 
Published: January 2010

Caldera‐related processes have deep implications in Earth science and are important to the general public. To the geologist, calderas are surface manifestations of large magma reservoirs and the source of some of the largest eruptions on Earth. For society, these volcanoes represent not only an extreme volcanic hazard but also a potential source of abundant geothermal energy and metal ore deposits.During February–April 2009, an innovative, online course entitled “Calderas: Bottom‐to‐top” was offered across several universities to students interested in investigating caldera‐forming processes associated with “supervolcanoes.” Supervolcanoes have the ability to spew hundreds to thousands of cubic kilometers of material from large magma chambers pooled in the Earth's crust. A caldera‐forming eruption results from overpressurization of the chamber and leads to formation of large depressions, tens of kilometers in diameter.
Erratum: Interactions between gut microbiota, host genetics and diet relevant to development of metabolic syndromes in mice
Authors: Zhang Chenhong , Zhang Menghui , Wang Shengyue , Han Ruijun , Cao Youfang , Hua Weiying , Mao Yuejian , Zhang Xiaojun , Pang Xiaoyan , Wei Chaochun , Zhao Guoping , Chen Yan , Zhao Liping 
Published: January 2010

Abstract
Correction to: The ISME Journal (2010) 4, 232–241; doi:10.1038/ismej.2009.112; published online 29 October 2009 Since the publication of this paper, the authors have noticed an error in Figure 4. The correct figure is shown here. The authors would like to apologize for any inconvenience this may have caused.
4 Engineers of Art
Authors: Oja Carol J. 
Published: January 2010

Abstract
Leo Ornstein and Edgard Varèse began imagining the dimensions of American modernism during the 1910s. But on the whole, the 20th century dawned for American composers in the 1920s. This was a decade when iconoclastic ideas blasted through hallowed traditions, with machines often providing the horsepower to do so. The decade quickly became known as the “Machine Age”—a rubric that in a broader sense has been used to cover the entire interwar period. For modernist composers in the United States, the machine had two powerful manifestations: it yielded new sound sources, and it provided new means of preserving and transmitting performances. One important facet of the machine movement in modernist music was the invention of new musical instruments. In New York City, these instruments were the Theremin, the Clavilux, the Crea-tone, the Vitaphone, and the Martenot. By no means a circumscribed movement that yielded a few art works and then ended, the machine aesthetic projected outward like a beam of light, illuminating future potential and suggesting unexplored aesthetic territory.
5 Ballet Mécanique and International Modernist Networks
Authors: Oja Carol J. 
Published: January 2010

Abstract
More than any other event, the premiere of George Antheil's Ballet Mécanique at Carnegie Hall in New York City on April 10, 1927 brought music's role in the American machine movement into focus. Antheil's concert was also unusual in challenging racial segregation and in arranging a Dada spectacle that spurned long-held assumptions of concert decorum. A siren, airplane propellers, a player piano, ten conventional pianos, six xylophones, and a battery of other percussion instruments clustered on stage. At once infamous and undervalued, Ballet Mécanique presents a vivid picture of modernism's international traffic. It drew upon the culture of Dada, with which Antheil came in contact as a teenager in the United States, and was conceived together with a film by the Spanish cubist Fernand Léger. Furthermore, Ballet Mécanique's position as an early percussion work gives it historic pride of place next to Edgard Varèse's Ionisation of 1929-1931.
9 Ruth Crawford and the Apotheosis of Spiritual Dissonance
Authors: Oja Carol J. 
Published: January 2010

Abstract
Alone among the ultra-moderns, Ruth Crawford (1901-1953) became a rapt disciple of Dane Rudhyar, whom she met in 1925. She soon fell under his spell, “worshipping” him “intellectually”and finding herself “dazzled by his erudition”. She revered him as an “idol”. Thus, one of America's most uncompromising modernists—a composer who within a few years was to be hailed for her proto-serial writing and heterophonic ideal—encountered spiritual theories during a formative period in her compositional development. Crawford was never promoted or explicated by Rudhyar, as was the case with Carl Ruggles and Henry Cowell. Crawford stood apart in actually applying Rudhyar's theories to her compositions and gaining little attention from him for the results. Rudhyar credited some of his own piano works with inspiring the “first really interesting music Crawford wrote”.
11 Organizing the Moderns
Authors: Oja Carol J. 
Published: January 2010

Abstract
In his second inaugural address of 1917, President Woodrow Wilson declared the end of post-colonial isolation and the beginning of international leadership. Once World War I was over, transatlantic relations in music reflected such sentiments as much as they did in politics. France, the United States's wartime ally, became its peacetime friend. Forces of internationalization resounded throughout the new music scene. In 1920, the Prix de Rome was first awarded, launching a fellowship program for creative artists at the American Academy in Rome that continues to the present. The Conservatoire Américain at Fontainebleau opened the following year in France, initiating an ambitious, long-reaching Franco-American interchange. There and then the young Nadia Boulanger welcomed Aaron Copland as a pupil, the first of many gifted American musicians who entered her studio during the next half of the century.
16 A Quartet of New World Neoclassicists
Authors: Oja Carol J. 
Published: January 2010

Abstract
The Copland-Sessions Concerts celebrated youth, giving performance opportunities to composers who would eventually emerge as leaders in the United States. The stylistic range of music performed on the series was far broader than is generally recognized, yet there is no denying that one of its main constituencies was made up of composers with varying inclinations toward neoclassicism. Four of them are Roger Sessions, Walter Piston, Roy Harris, and Carlos Chávez, who, when placed alongside Aaron Copland and Virgil Thomson, broaden our perspective on the diversity of American attitudes toward neoclassicism. Sessions and Piston both adopted fairly traditional stances toward the aesthetic yet achieved quite different results, whereas Harris and Chávez took much more idiosyncratic approaches. All four negotiated individual contracts with this transatlantic aesthetic in some of their earliest mature works. Among American composers born around the turn of the century, Sessions was the one most comfortable with his connection to the music and traditions of Western Europe.
17 Europeans in Performance and on Tour
Authors: Oja Carol J. 
Published: January 2010

Abstract
While American neoclassicists obscured their stylistic connection to Western Europe, these same composers and their American contemporaries worked to foster transatlantic performance opportunities. The founding of New York City's modern music societies in the early 1920s generated a booming trade in European modernism, and other strategic points of Euro-American contact occurred, including especially the New York premieres of Pierrot lunaire and Le Sacre du printemps, the establishment of the International Society for Contemporary Music, and the United States tours of European composers. Through these tours and premieres, New York City not only caught up with Western Europe in presenting continental modernism but also became a desirable locale in its own right. Even though visiting European luminaries seemed to pay little attention to American composers of concert music, they helped alter the overall climate for modernism. As every year passed, New York seemed less provincial, and its young composers benefited from the difference.
18 Visionary Critics
Authors: Oja Carol J. 
Published: January 2010

Abstract
As contemporary European music arrived in the United States and Americans devised their own brands of modernism, a new generation of critics took on a parallel challenge, attempting to interpret these rapid developments for a public that was often bewildered. While their ranks were not large, a few key figures rallied to the cause of the avant-garde. One of them was Carl Van Vechten, who wrote perceptive, even prescient evaluations of new music during the mid-1910s, just as the modernist movement began taking hold in New York City. The other was Paul Rosenfeld, who became an advocate of modernism in all the arts. Like Van Vechten, Rosenfeld's great awakening to modernist music came while traveling abroad: during a visit in 1914 to London, where he first heard the music of Alexander Scriabin. As music critics, both Van Vechten and Rosenfeld agitated for cultural change and grappled with contemporary European figures as well as American popular idioms. However, the two ended up in very different positions. Van Vechten's role in early 20th-century modernism is now largely forgotten, while Rosenfeld is lionized as one of modernism's great interpreters.
After Hitler
Authors: Jarausch Konrad H. 
Published: January 2010

Abstract
This book deals with the transformation of Germany after the Second World War and the Holocaust into a Western, democratic, and therefore civilized country. It proceeds in three stages, beginning with the Allied post-war policies of demilitarization, denazification, and decartelization. In the second part, it concentrates on the Westernization, inner democratization and generational rebellion of the 1960s, concluding with a section on the repudiation of Communism, the return to normalcy, and the issue of immigration during the 1990s.