bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of embryonic cell cycle of nuclear donor embryos on the efficiency of nuclear transfer in Japanese black cattle
Authors: Kishi M. , Takakura R. , Nagao Y. , Saeki K. , Takahashi Y.
Published: April 2007

In the present study, the development in vitro and in vivo of nuclear transfer (NT) embryos reconstructed with embryonic cells (blastomeres) at the 32- to 63-cell (sixth cell cycle) and 64- to 127-cell (seventh cell cycle) stages was investigated to determine the optimum range of embryonic cell cycles for yielding the highest number of identical calves in Japanese black cattle. Rates of development to the blastocyst stage (overall efficiency) were higher in the sixth cell-cycle stage (45%) than in the seventh cell-cycle stage (12%). After the transfer of the blastocysts reconstructed with blastomeres of the sixth and seventh cell cycle-stage embryos to recipient heifers, there were no differences in the pregnancy (14/35: 40% versus 3/13: 23%, respectively) or calving rates (11/39: 28% versus 3/13: 23%, respectively). These results indicate that the highest number of identical calves would be obtained by using sixth cell cycle (32- to 63-cell)-stage embryos as nuclear donors.
Comics and Cartoons: A Democratic Art-Form
Authors: Maggio J.
Published: April 2007

The cartoon, comic, or—as influential cartoonist Will Eisner
called it—“sequential art” is an art-form that is
cognitively friendly to contemporary notions of
individualistic-liberal-democracy. Whereas traditional forms of art have
rather hierarchical standards of aesthetics, which then enforce customary
notions of power and the conventional hermeneutic pecking order, the
iconography of comics and cartoons is supportive of a kind of pluralistic
democratic individualism. If, as some thinkers suggest, the world is
understood by cognitive images in the brain, then—as the work of C.
S. Pierce, Scott McCloud, and others support—comics is an art that
allows for the individual self-creation that subsequently supports
democracy.
The Animated Persuader
Authors: Moss Dori
Published: April 2007

Media are not politically neutral and political cartoons are no
exception. Political viewpoints can be made clear through explicit
argumentation, and through the more implicit use of visual elements. One
prominent example that unites argumentation with the visual to produce
political persuasion is America's first political cartoon, created by
Benjamin Franklin in 1754, which frames the socio-political climate of the
time with an image urging the British colonies to “Join, or
Die” (Katz 2004, 44). The themes of
political cartoons, despite technological progress, remain unaltered by
way of their continual incorporation of “domestic politics, social
themes and foreign affairs” (Kemnitz 1973,
83). While members of the academic community, such as Lester C. Olson
(1987), support this connection between
cartooning and persuasive rhetoric, there is much we don't know about
how the persuasive arguments within political cartoons work.
Stop the Student Press: Editorial Cartooning on College
Campuses
Authors: Healy Shawn P.
Published: April 2007

In Hazelwood v. Kuhlmeier (1988),
the U.S. Supreme Court refused to extend free press protections to student
newspapers at the high school level, supporting an administrator's
decision to remove two articles prior to publication. The majority held
that “First Amendment rights of students are not automatically
coextensive with the rights of adults in other settings, and must be
applied in light of the special characteristics of the school
environment.” They claimed that school newspapers were not a
“forum for public expression,” and authorized the prior
restraint exercised by the administrator “so long as [his]
actions [were] reasonably related to legitimate pedagogical
concerns.”
Representations of 9-11 in Editorial Cartoons
Authors: Hoffman Donna R. , Howard Alison D.
Published: April 2007

Throughout American history editorial cartoons have exposed
corruption, offered criticism of people in power, questioned and supported
policies, and in general given the public another format assisting in the
understanding of current events. The freedom to caricature politicians and
visually comment on social and political issues has been a hallmark of the
editorial cartoonist's profession. In the aftermath of the worldwide
furor over Danish cartoonists' use of the Prophet Muhammad's
image in early 2006, it is useful to ask whether certain images from the
War on Terror have become taboo as a subject for American editorial
cartoonists.
Web Cartoons in a Closed Society: Animal Farm as an
Allegory of Post-Communist Belarus
Authors: Nikolayenko Olena
Published: April 2007

Political humor directed at President Alyaksandr Lukashenka is beyond
the official boundaries of the permissible in Belarus, a former Soviet
Republic tucked away on the eastern border of the European Union and oft
labeled “Europe's last dictatorship.” In August 2005, KGB
officers raided the Minsk office of the civic group Third Way, confiscated
the computer equipment, and threatened criminal charges for posting
animated cartoons on the group's web site (http://mult.3dway.org). Oleg Minich, the
cartoonist and founder of the virtual cartoon club Multclub,
faced imprisonment of up to five years. His alleged crime falls under
Article 367 of the Criminal Code, “Defamation of the President of
the Republic of Belarus.” This flagrant attack on the freedom of
expression was part of a broader crackdown on the mass media in
preparation for the 2006 presidential election.
Roads “Drawn” to Modernity: Religion and Secularism in Contemporary Turkey
Authors: Taç Hakkı , Uğur Meral
Published: April 2007

Editorial cartoons do not just mirror politics, but are also themselves a part of politics. They are more than single-panel graphical commentaries on daily policies, for they construct their own claims on truth. The cartoonist can use the polysemic nature of visual signs and present a distinct framing perspective. Editorial cartoonists with certain ideological stances can become an actor in “the struggle for cultural supremacy,” in Tarrow's (1998) term. This struggle refers to efforts by the state, media, and social movements to influence the interpretative processes by which individuals negotiate the meaning of events. This paper analyzes the editorial cartoons in Turkish daily newspapers in terms of their competing framings of contemporary Turkey's secularist-Islamist division. Secularism and Islamism refer here to political projects that seek to transform and reinstitute a sociopolitical order on the basis of some constitutive norms (Çınar 2005, 8–9).
Zapiro: The Work of a Political Cartoonist in South
Africa—Caricature, Complexity, and Comedy in a Climate of
Contestation
Authors: Koelble Thomas A. , Robins Steven L.
Published: April 2007

Jonathan Shapiro, better known as Zapiro, is South Africa's most
influential and widely published political cartoonist. His work is
featured in several national daily and weekly newspapers. His cartoons
have also appeared in international publications and he or his work has
been featured in everything from highbrow newspapers to the front page of
real estate advertisement magazines. A member of the anti-apartheid
movement in the 1980s, he exhibits a bias toward a progressive,
Left-liberal conception of what political life ought to be that sits
uncomfortably with the increasingly Africanist tonality pulsating through
the veins of South African political life. His work touches upon the
history of oppression, the reactions of those in and now out of power,
and, in more recent years, on the issues that arise from the
“underbelly” of the liberation movement. He has brutally
caricatured the foibles of liberation movements leaders, be it their AIDS
denial, individuals' cases of corruption, or the hypocrisy of ethnic
or racial mobilization in the context of the new, non-racial dispensation.
His particular wrath is reserved for African National Congress (ANC)
figures who have, in his view, defiled the principles of the liberation
movement. In the last two years, Zapiro has busied himself with a series
of cartoons about the trials and tribulations of the former deputy
president and leader of the ANC, Jacob Zuma.
A Half-Century Perspective on APSA Annual Meetings
Authors: Loewenberg Gerhard
Published: April 2007

Iattended my first American Political Science Association meeting in
1949. It was an exciting experience for me as a first-year graduate
student. I already venerated several established scholars in the
profession. Herman Finer and Carl Friedrich were the towering figures on
my intellectual landscape in comparative politics, my major field. In
American politics, in which I was a teaching assistant, Edward S. Corwin
and Carl B. Swisher were giants. And here they were, conspicuous in the
halls of the hotel, standing for hours, as I recall, each in his own
place, talking with groups of awe-struck students. The greats of the
profession were suddenly real people rather than simply names on books.
The APSA membership included a significant cadre of political leaders,
public figures, and well-known journalists. I was astonished to see
Senators Hubert Humphrey and Paul Douglas, Congressman Jacob Javits, Ralph
Bunche, who had just served as acting UN Mediator on Palestine, and Max
Lerner, a noted editorial writer and political theorist.
The Methods Café: An Innovative Idea for Methods Teaching at
Conference Meetings
Authors: Yanow Dvora , Schwartz-Shea Peregrine
Published: April 2007

Interpretive research methods of various sorts have long been used to
study “the political,” but the full range of such methods is
not widely known, and many are curious about what they entail. Others, who
begin to use one or another of them, have questions about how to proceed.
For those just learning about these methods, questions may be as basic as:
“What does ethnomethodology mean?” “What is semiotic
analysis?” “Are these approaches recognized as legitimate in
political science?” Scholars engaging, or perhaps teaching, these
methods might ask, e.g., “How do ethnographers overcome problems of
accessing their field site, talking to strangers, and turning a
year's worth of observational and interview notes into concise
text?” We thank 2005 and 2006 Program
Chairs Ron Schmidt and Val Martinez-Ebers and Executive Director Betty
Moulds and Associate Director Elsa Favila at the Western Political Science
Association, and Qualitative Methods 2006 Section Program Chairs Julia
Lynch and Melani Cammett, and Michael Brintnall, Rob Hauck, Christina
Marmor, and others on the conference organizing staff at APSA. Michael and
Rob came to the Café at the Western in 2006 to see for themselves
what it was that we were trying to do. We are grateful for their help in
making it possible at APSA. And, of course, we thank all those colleagues
who have contributed their time and thought to creating the Café
with us, including Cecelia Lynch, who saw right at the beginning that it
was a ‘café’ and came up with its definitive
name.
Divided Senate Delegation Indicator of Realignment
Authors: Brunell Tom , Grofman Bernard
Published: April 2007

In a research note written in 2005 and subsequently rejected by three
leading political science journals as too speculative and not adequately
statistically anchored, we sought to update Brunell and Grofman's
1998 research note in the APSR on
divided Senate delegation by showing that we were right in predicting
that, in the Senate election years taking place immediately after our
original data analyses, the number of states with divided Senate
delegations would continue to decline. It did: from 19 states in 1996 to
18 in 1998, way down to 13 in 2000 and remaining at that level until the
most recent election in 2006. However, at the end of our 2005 paper we
also say: “Unlike Brunell and Grofman (1998), though, we are not prepared to predict further
decreases in the number of divided Senate delegations.”
Meeting the Challenges of Senate Leadership
Authors: Doherty Brendan J.
Published: April 2007

Political scientists have long acknowledged the substantial challenges
of and obstacles to effective majority leadership in the Senate. As each
individual senator, regardless of rank or party affiliation, has the right
to object to unanimous consent agreements that govern much of the
Senate's business, to offer non-germane amendments to pending
legislation, and to engage in extended debate that can only be halted by
mustering 60 votes to invoke cloture, the agenda of the Senate leadership
can be easily derailed. The tendency of senators to obstruct and delay has
been exacerbated over the past half century by the rise of individualism
and partisanship in the Senate, which has resulted in commensurate
increased challenges for Senate leaders (see, for example, Polsby 1971; Sinclair 2005;
Davidson and Oleszek 2006).
Report of the Editor of the American Political Science
Review, 2005–2006
Authors: Sigelman Lee
Published: April 2007

My last two annual reports sounded a theme of continuity from year to
year in the number and variety of the papers that we received and the
articles that we published and in the pace of our review process. This
year, too, many of these elements have differed only slightly from those
of past years. In some important respects, though, 2005–2006 has
been a significant departure from the years immediately preceding it. For
one thing, as detailed below, during 2005–2006 we received a record
number of submissions. For another, while we were considering more papers
than ever before, we were simultaneously faced with the self-imposed
challenge of conducting a separate review process for the November 2006
centennial issue of the Review.
Regulation of avoidant behaviors and pain by the anti-inflammatory tyrosine phosphatase SHP-1
Authors: Hudson Chad A. , Christophi George P. , Cao Ling , Gruber Ross C. , Massa Paul T.
Published: April 2007

The protein tyrosine phosphatase SHP-1 is a critical regulator of cytokine signaling and inflammation. Mice homozygous for a null allele at the SHP-1 locus have a phenotype of severe inflammation and are hyper-responsive to the TLR4 ligand LPS. TLR4 stimulation in the CNS has been linked to both neuropathic pain and sickness behaviors. To determine if reduction in SHP-1 expression affects LPS-induced behaviors, responses of heterozygous SHP-1-deficient (me/+) and wild-type (+/+) mice to LPS were measured. Chronic (4-week) treatment with LPS induced avoidant behaviors indicative of fear/anxiety in me/+, but not +/+, mice. These behaviors were correlated with a LPS-induced type 2 cytokine, cytokine receptor, and immune effector arginase profile in the brains of me/+ mice not found in +/+ mice. Me/+ mice also had a constitutively greater level of TLR4 in the CNS than +/+ mice. Additionally, me/+ mice displayed constitutively increased thermal sensitivity compared to +/+ mice, measured by the tail-flick test. Moreover, me/+ glial cultures were more responsive to LPS than +/+ glia. Therefore, the reduced expression of SHP-1 in me/+ imparts haploinsufficiency with respect to the control of CNS TLR4 and pain signaling. Furthermore, type 2 cytokines become prevalent during chronic TLR4 hyperstimulation in the CNS and are associated positively with behaviors that are usually linked to type 1 pro-inflammatory cytokines. These findings question the notion that type 2 immunity is solely anti-inflammatory in the CNS and indicate that type 2 immunity induces/potentiates CNS inflammatory processes.
The Tully-Fisher Relation as a Function of Redshift: Disentangling Galaxy Evolution and Selection Biases
Authors: Vogt Nicole P.
Published: April 2007

We review the status of current observations of the fundamental parameters of intermediate redshift (z≤ 1.2) disk galaxies. Advances in instrumentation of 8-10m class telescopes have made possible detailed measurements of galaxy luminosity, morphology, kinematics and mass, in both the optical and the infrared passbands. By studying such well known star formation indicators as [OII]3727A (in the optical) and Hα (redshifted to the infrared), the internal velocity structure and star formation rates of galaxies can be traced through this entire redshift regime. The combination of throughput and optimum seeing conditions yields spectra which can be combined with high resolution multiband imaging to explore the evolution of galaxies of various morphologies, and to place constraints on current models of galaxy formation and star formation histories.

Out to redshifts of unity, these data form a high redshift Tully-Fisher relation that spans four magnitudes and extends to well below L*, with no obvious change in shape or slope with respect to the local relation. A comparison of disk surface brightness between local and high redshift samples yields an offset in accordance with distance-dependent surface brightness selection effects, as can the apparent change in disk size with redshift for disks of a given mass. These results support low Ω0models of formation, and provide further evidence for modest increases in luminosity with lookback time for the bulk of the observed field spiral galaxy population.

Finally, a comparison of spatially resolved spectra versus integrated emission line widths for distant galaxies suggests that observational constraints bias each type of observational sample toward different sub-groups of galaxies, with different evolutionary histories. Like varying selection effects, this will lead to a wide range of projected evolutionary trends.
The Tully-Fisher relation: evolution with redshift and environment
Authors: Aragón-Salamanca Alfonso
Published: April 2007

The Tully-Fisher Relation (TFR) links two fundamental properties of disk galaxies: their luminosity and their rotation velocity (mass). The pioneering work of Vogt et al. in the 1990's showed that it is possible to study the TFR for spiral galaxies at considerable look-back-times, and use it as a powerful probe of their evolution. In recent years, several groups have studied the TFR for galaxies in different environments reaching redshifts beyond one. In this brief review I summarise the main results of some of these studies and their consequences for our understanding of the formation and evolution of disk galaxies. Particular emphasis is placed on the possible environment-driven differences in the behaviour of the TFR for field and cluster galaxies.
Building Galactic Disks in Triaxial Dark Matter Halos
Authors: Shlosman Isaac
Published: April 2007

We review our recent work on the formation and evolution of disks within triaxial dark matter (DM) halos by means of numerical simulations, including star formation and feedback from stellar evolution. The growing disks are strongly influenced by shapes of DM halos and modify them in turn. Disk parameters are in a broad agreement with those in the local universe. Gas-rich stellar bars grow in tandem with the disk and facilitate the angular momentum redistribution in the system and radial gas inflow. Nested bars appear to form as a by-product. Interactions between various non-axisymmetric components—bars, disks and halos lead to decay of bars or washing out of ellipticity in the inner halo.
Stellar Population Models
Authors: Maraston Claudia
Published: April 2007

I review the current status of stellar population modelling, with particular emphasis on the treatment of the Thermally-Pulsing Asymptotic Giant Branch stellar phase. I discuss how much the physical properties of galaxies that are derived applying these models to real data, depend on the adopted model.
Are the most metal-poor galaxies young?
Authors: Kunth Daniel , Östlin Göran
Published: April 2007

We review the possibility that metallicity could provide a diagnostic for the age of a galaxy, hence that the most metal-poor star forming galaxies in the local universe may be genuinely young. Indeed, observational evidence for “downsizing” shows the average age of the stars in a galaxy to decrease with decreasing mass and metallicity. However, we conclude both from observational and theoretical viewpoints that metallicity is not an arrow of time. Consequently the most metal–poor galaxies of our local universe are not necessarely young. Current observations suggest that an old stellar population is present in all metal-poor galaxies, although a couple of cases, e.g. IZw18, remain under debate. Further observations with more sentitive equipement should settle this question in the coming years.
Integrated Spectral Analysis of 10 Concentrated Galactic Open Clusters
Authors: Ahumada A. V. , Clariá J. J. , Bica E.
Published: April 2007

Integrated spectra of 10 concentrated Galactic open clusters were obtained in the (3600-6800)Å range using the CASLEO (Argentina) 2.15 m telescope. The method used to determine ages and reddening of the clusters consists of the following steps: (1) Estimation of the cluster age from equivalent widths of the Balmer lines. This age is practically independent of the reddening. (2) Choice of the template whose spectral features better resemble those of the observed spectrum. This choice was made by using the libraries of template spectra which were available at the moment of making use of this methodology. In a first approach, the age inferred by the previous method was adopted. (3) Variation of the reddening of the observed spectrum until obtaining the best match to the chosen template. The reddening corrections were done using the normal reddening law. In Table 1 we show the parameters derived here, where the ages values are in Myr.

Five out of the ten studied clusters have not been the subject of previous studies so that their fundamental parameters determined turn out to be the first of their kind. For the remaining clusters, the parameters derived exhibit good agreement with those determined in previous studies.

With the exception of ESO429-SC2, the remaining Galactic open clusters are located within two 90°. sectors centered at l = 343° and l = 253°, respectively. A comparison of the properties of the Galactic open clusters here studied to those of well-known clusters located in the above mentioned sectors, shows that, unless major star forming events had occurred in the Galactic disk in the last 100 Myr or so, the present results would favour an important dissolution rate of star clusters in the above mentioned Galactic sectors.
Constraints on Bars in the Local Universe from 5000 SDSS Galaxies
Authors: Barazza Fabio D. , Jogee Shardha , Marinova Irina
Published: April 2007

We present the first study of bars in the local Universe, based on the Sloan Digitized Sky Survey (SDSS). The large sample of ~5000 local galaxies provides the largest study to date of local bars and minimizes the effect of cosmic variance. The sample galaxies have Mg ≤ −18.5 mag and cover the redshift range 0.01 ≤ z < 0.04. We use a color cut in the color-magnitude diagram and the Sérsic index n to identify disk galaxies. We characterize bars and disks using r-band images and the method of iterative ellipse fits and quantitative criteria developed in Jogee at al. (2004, ApJL, 615, L105). After excluding highly inclined (i>60°) systems our results are: (1) the optical (r-band) fraction of barred galaxies among local disk galaxies is 43% (Figure 1, left panel), which confirms the ubiquity of local bars, in agreement with other optical studies based on smaller samples (e.g. Eskridge et al 2000, AJ, 119, 536, Marinova & Jogee 2006, astro-ph/0608039); (2) the optical bar fraction rises for bluer galaxies, suggesting a relation between bars and star formation (Figure 1, middle panel); (3) preliminary analyzes suggest that the optical bar fraction increases steeply with the galaxy effective radius (reff, Figure 1, right panel); (4) the optical bar fraction at z ~ 0 is ~35% for bright disks (Mg ≤ −19.3 mag) and strong (bar ellipticity >0.4), large-scale (bar semi-major axis >1.5 kpc) bars, which is comparable to the value of ~30 ± 6% reported earlier (Jogee et al 2004) for similar disks and bars at z ~ 0.2 − 1.0.
Discrete Schwarzschild Models: Constraining Dark Halos and Black Holes
Authors: Chanamé Julio , van der Marel Roeland , Kleyna Jan
Published: April 2007

We have developed a code for modeling 3-dimensional kinematical data (i.e., both radial velocity and proper motions) of individual tracers in stellar systems. The code relies on the Schwarzschild method of orbit superposition to find the distribution function (a function of energy, angular momentum, and third integral of motion) that best reproduces all the observations (the positions and velocities of the tracers as well as the overall light distribution) in a given potential. Previous implementations of this method have generally focused on fitting integrated light measurements, instead of data for individual tracers. However, the latter is the only data that are generally available in a large class of problems (e.g., kinematics of tracers in nearby globular clusters, kinematics of planetary nebulae or globular clusters in galaxy halos, etc.). We have performed extensive tests of the fitting process by making use of data generated by a well-tested N-body simulation of an axisymmetric galaxy, quantifying how well the code can recover the known input distribution function and potential.
Entropy of The Mixture Probability as Indicator of Population Discontinuities: MEMPHIS Algorithm
Authors: Cubarsi Rafael , Alcobé Santiago
Published: April 2007

A statistical population is always associated with the distribution of a random variable. If the distribution is too complex, it is useful to think about a superposition of simpler components. For the stellar velocities, the distribution is generally assumed as a mixture of gaussian distributions, since these are particular solutions of Chandrasekhar equations for statistical equilibrium, easy to interprete dynamically. In any case, the nature of the phase space density function might be explained from the dynamics of large stellar groups, sharing a common potential, through integrals like the energy, the angular momentum, or more general quadratic integrals, rather than from the kinematics of particular groups of stars, such as those producing streaming motions. Another fact to point out is that a well defined population must be adult, that is, well described from some constant and consistent statistics. Otherwise, if a sample estimate varies depending on an external parameter, for example the mean age of a sample, then, either the type of distribution might be exchanged, or the population might be divided into an adequate number of subpopulations.

In this context, the MEMPHIS algorithm (Alcobé & Cubarsi 2005) has demonstrated to be useful in order to identify nearby stellar populations, by using the full space motions of a stellar sample obtained from the Hipparcos catalog (Cubarsi & Alcobé 2004). A sampling parameter, the modulus of the velocity |V|max, produces a hierarchical set of nested samples allowing to detect significant population components of their velocity distribution. Although the method was designed to identify normal distributions, it also provides, as a less prior information pattern, a good approach to segregate non-gaussian populations. The entropy variations of the mixture probability allow us to estimate the number of populations without any prior assumption about such a number, according to the parameters of the Table below (sampling parameter, velocity dispersions, means –in Km s−1– and vertex deviation are displayed in the UVW-cartesian heliocentric coordinates system). The main disk structure is supported by two gaussian populations, thin and thick disk. Two subcomponents were found within the thin disk, which have a high deviation from gaussianity in the radial direction, as a consequence of a non-random behaviour (Cubarsi & Alcobé 2006), but not in the other directions. Old disk stars were obtained as a broad wing of the young-thin disk. All together, with the early-thin population, they make up the thin disk component. In total 2+2 populations, since halo stars were not included in the sample.
Radio Observations of the AGN and Gas in Low Surface Brightness Galaxies
Authors: Das M. , O'Neil K. , Kantharia N. , Vogel S. N. , McGaugh S. S.
Published: April 2007

LSB galaxies have low metallicities, diffuse stellar disks, and massive HI disks. We have detected molecular gas in two giant LSB galaxies, UGC 6614 and F568-6. A millimeter continuum source has been detected in UGC 6614 as well. At centimeter wavelengths we have detected and mapped the continuum emission from the giant LSB galaxy 1300+0144. The emission is extended about the nucleus and is most likely originating from the AGN in the galaxy. The HI gas distribution and velocity field in 1300+0144 was also mapped. The HI disk extends well beyond the optical disk and appears lopsided in the intensity maps.
NMAGIC: Fast Parallel Implementation of a χ2-Made-To-Measure Algorithm for Modeling Observational Data
Authors: De Lorenzi Flavio , Debattista Victor P. , Gerhard Ortwin , Sambhus Niranjan
Published: April 2007

We describe a made-to-measure algorithm (χ2M2M) for constructing N-particle models of stellar systems from observational data (De Lorenzi Debattista, Gerhard, et al. (2007)), extending earlier ideas by Syer & Tremaine (1996). The algorithm properly accounts for observational errors. We implemented this algorithm in a parallel code NMAGIC and carried out a sequence of tests to illustrate its power and performance: (i) We reconstructed an isotropic Hernquist (1990) model from density moments and projected kinematics including higher-order Gauss-Hermite moments (Gerhard (1993), van der Marel & Franx (1993)). We gave NMAGIC two initial models, made from distribution function (Debattista & Sellwood (2000)), with different density distributions to start with. While both recovered the correct differential energy distribution and intrinsic kinematics, that with density closer to the density of the final model had smaller final deviations from the target observables, and a narrower distribution of weights. (ii) We built a self-consistent oblate three-integral maximum rotator model and compared how the distribution function is recovered from integral field and slit kinematic data. In these experiments we gave the algorithm a difficult problem to solve. Since the target system was maximally rotating, the weights of all counter-rotating particles were zero. Using density observables and either slit or integral field kinematics, NMAGIC was asked to recover this maximally rotating model starting from an isotropic spherical system. A good fit to the kinematic constraint data was achieved. These experiments also showed the advantage of integral field data over slit data for constraining the model. The different applications show that the χ2M2M algorithm is practical, reliable and can be applied to various systems. High quality dynamical models of galaxies can be achieved which match targets to ~1σ for plausible uncertainties in the observables, and without symmetry restrictions. We conclude that χ2M2M holds great promise for unraveling the nature of galaxies.
Abundances and Kinematics for a Sample of LMC Clusters
Authors: Geisler Doug , Grocholski Aaron J. , Sarajedini Ata , Cole Andrew A. , Smith Verne V.
Published: April 2007

We present results from a project aimed at better understanding the kinematics and metallicities of populous clusters in the LMC. In an effort to update previous [Fe/H] determinations, we have utilized FORS2 on the VLT to obtain infrared spectra for more than 200 stars in 28 LMC clusters. The absorption lines of the calcium II triplet were then used to calculate radial velocities and [Fe/H] for a sample of clusters spanning a large range of ages (~ 1-13 Gyr) and metallicities (−0.3 >[Fe/H]> − 2.0). We determine mean cluster velocities to typically 1.6 km s−1 and mean metallicities to 0.04 dex (random error). For eight of these clusters, we report the first spectroscopically determined metallicities based on individual cluster stars, and six of these eight have no published radial velocity measurements. Combining our data with archival HST/WFPC2 photometry, we find the newly measured cluster, NGC 1718, is one of the most metal-poor ([Fe/H] ~ −0.80), intermediate age (~ 2 Gyr) inner disk clusters in the LMC. Similar to what was found by previous authors, this cluster sample has motions consistent with that of a single rotating disk system, with no indication that the newly reported clusters exhibit halo kinematics. Additionally, our findings confirm previous results which show that the LMC lacks the metallicity gradient typically seen in non-barred spiral galaxies, suggesting that the bar is driving the mixing of stellar populations in the LMC. However, in contrast to previous work, we find that the higher metallicity clusters (≥−1.0 dex) in our sample show a very tight distribution (mean [Fe/H] = −0.48, σ = 0.09), with no tail toward solar metallicities. The cluster distribution is similar to what has been found for red giant stars in the bar, which indicates that the bar and the intermediate age clusters have similar star formation histories. This is in good agreement with recent theoretical models that suggest the bar and intermediate age clusters formed as a result of a close encounter with the SMC ~ 4 Gyr ago.
New Spectral Templates of Galaxies for Multi Color Classification
Authors: Franco I. , Meisenheimer K. , Wolf C. , Bell E. , Nicol M. H. , Tapken C.
Published: April 2007

Observations in the Chandra Deep Field South (CDFS) have provided us with a useful set of data in the optical (COMBO-17), near-infrared (GOODS JHK), and mid-infrared (GOODS IRAC bands 1,2) wavelength regimes to test and improve a new spectral galaxy template library, designed to operate in the rest-frame wavelength range between 0.1 and 5 microns. In this range the stellar continuum and emission lines from HII regions dominate the Spectral Energy Distribution (SED) of galaxies. The new library is based on a self-consistent two-burst model, that has been developed in order to reproduce the star formation histories of different types of galaxies more accurately than single-burst histories and thus provides a better match to real galaxy spectra, as well as more reliable mass-to-light ratios. The spectral library is built by using a population synthesis code (PEGASE) assuming a Kroupa (2003) initial mass function. An old burst of exponentially decaying star formation with an initial metallicity of 0.1 solar is followed by a very recent (60 Myr old) second burst in order to reproduce the spectra of actively star forming blue galaxies. In addition, the templates include dust extinction of various strengths. For the multi-color classification the spectral library is red-shifted between z + 0 and z + 2.5 and converted into the 21 colors which have been observed by COMBO-17 plus its near- and mid-infrared extensions provided by the public GOODS data.
On the Lengths, Colours and Ages of Bars
Authors: Gadotti Dimitri A. , de Souza Ronaldo E.
Published: April 2007

In an effort to obtain further observational evidences for secular evolution processes in galaxies, as well as observational constraints to current theoretical models of secular evolution, we have used BVRI and Ks images of a sample of 18 barred galaxies to measure the lengths and colours of bars, create colour maps and estimate global colour gradients. In addition, applying a method we developed in a previous article, we could distinguish for 7 galaxies in our sample those whose bars have been recently formed from the ones with already evolved bars. We estimated an average difference in the optical colours between young and evolved bars that may be translated to an age difference of the order of 10 Gyr, meaning that bars may be long standing structures. Moreover, our results show that, on average, evolved bars are longer than young bars. This seems to indicate that, during its evolution, a bar grows longer by capturing stars from the disk, in agreement with recent numerical and analytical results.
Rotation Curves of Dwarf Irregulars: Still a Big Challenge for ΛCDM
Authors: Gentile Gianfranco
Published: April 2007

I present the analysis of HI data of two nearby dwarf irregular galaxies: DDO 47 and NGC 3741, whose rotation curves are best fitted by a cored halo, while they are inconsistent with an NFW halo. In DDO 47 non-circular motions are too small to explain the discrepancy with the ΛCDM predictions. NGC 3741 has the most extended rotation curve ever observed, in terms of the optical size.
A Photometric and Spectroscopic Study of Non-barred Ringed Galaxies
Authors: Grouchy R. , Buta R.
Published: April 2007

We present preliminary analysis of an imaging survey of non-barred ringed galaxies (NBRGs). We have taken broadband, narrow band, and spectroscopic data for a sample of NBRGs selected from the Third Reference Catalogue of Bright Galaxies and the Catalogue of Southern Ringed Galaxies. These galaxies are the subject of a survey in order to (1) better understand the mode of ring formation in the absence of a strong bar and (2) delineate the general photometric and spectroscopic properties of this group as a whole.
Gas Dynamics in AGN Galaxies: First Results of the HI-NUGA Survey
Authors: Haan S. , Schinnerer E. , Mundell C.G. , García-Burillo S. , Combes F.
Published: April 2007

The process of fueling Active Galactic Nuclei (AGN) in galaxies is commonly associated with gas aggregation onto a central supermassive black hole. Up to now a general picture of the AGN fueling is missing: What mechanisms are responsible for the various kinds of AGNs? How to remove angular momentum from the material far away from the gravitational influence of the central black hole? Over the last decade observations have been pointing towards a hierarchy of mechanisms that all combine to transport the gas from the large kpc scales down to the inner pc scales. In addition, fueling mechanisms excited by the galactic environment, e.g. through minor mergers and tidal interactions, have been suggested.

In order to study the gas transport from the outskirts of galaxies to the central AGN, we have embarked on a key project, NUGA (Nuclei of Galaxies): a high spectral and angular resolution CO and HI survey of low luminosity AGN in nearby galaxies (i.e. Seyferts, LINERs and transition objects).

For our detailed HI study, 16 nearby AGN galaxies were observed in their 21 cm line emission of neutral HI gas using the NRAO Very Large Array (VLA) interferometer in its C- and D-array configuration (~20'' angular and ~5.2 km s−1 spectral resolution). The spiral galaxies in our sample range in Hubble type from Sa to Sbc. For all galaxies high quality mm-interferometric CO data as well as optical/NIR imaging data are available.

Here, we present first results on the atomic gas distribution and kinematics in these galaxies: The HI gas properties are analyzed and then compared to the optical properties. Their HI morphology reveals a wide variety: rings, spiral arms, and central concentrated, where ring structures are mostly found in LINER hosts. The integrated surface brightness profiles show some significant differences between the HI gas and stellar light as well as their radial extent. Our analysis of the HI environment yields that 4 galaxies are surrounded by satellites and 8 galaxies have disturbed outer HI disks, probably due to ram pressure stripping and/or minor mergers. Our analysis of the HI kinematics provides rotation curves, dynamical masses and evidence for streaming motions for each galaxy.

The inclusion of recently obtained VLA B-array data will provide ~7″ resolution for more than half of the sample. We will utilize gravity torques based on a definite phase shift between the gravitational potential and the HI gas distribution to determine the gas inflow, and thus the efficiency for feeding the central black hole. Further, the combined CO+HI+NIR/opt data will allow us to develop dynamical models describing the gas flow in galactic disks from the large kpc scales down to the inner pc scales for selected galaxies in our sample.
Rotation of Galaxy Dark Matter Halos
Authors: Herbert-Fort Stéphane , Zaritsky Dennis , Kim Yeun Jin , Bailin Jeremy , Taylor James E.
Published: April 2007

The degree to which outer dark matter halos of spiral galaxies rotate with the disk is sensitive to their accretion history and may be probed with associated satellite galaxies. We use the Steward Observatory Bok telescope to measure the sense of rotation of nearby isolated spirals and combine these data with those of their associated satellites (drawn from SDSS) to directly test predictions from numerical simulations. We aim to constrain models of galaxy formation by measuring the projected component of the halo angular momentum that is aligned with that of spiral galaxy disks, Jz. We find the mean bulk rotation of the ensemble satellite system to be co-rotating with the disk with a velocity of 22 ± 13 km/s, in general agreement with previous observational studies and suggesting that galaxy disks could be formed by halo baryons collapsing by a factor of ≈10. We also find a prograde satellite fraction of 51% and Jz, of the satellite system to be positively correlated with the disk, albeit at low significance (2655 ± 2232 kpc km/s).
Near Infrared Survey of the Nuclear Regions of the Milky Way
Authors: Joshi U. C. , Ganesh S. , Baliyan K. S. , Glass I. S. , Nagata T.
Published: April 2007

Results based on the deep imaging survey of the inner region (~300pc of the bulge within |ℓ| ~ 1.5°, |b| ~ 0.5°) of the Milky Way are reported in this communication. This survey is about 2.5 magnitude deeper than DENIS and 2MASS and is able to detect stars of the red clump at a distance of the Galactic center. Toward some directions we find extinction reaching AV = 50 mag. A catalog of the sources is in preparation.
An Evolutionary Disc Model of NGC 5907
Authors: Just Andreas , Möllenhoff C. , Borch A.
Published: April 2007

We present the first physical disc model of NGC 5907, which reproduces simultaneouly the multi-band photometry in U, B, V, R, and I- band (Just et al., 2006, A&A in press, astro-ph/0608196). The model is based on the star formation history and dynamical evolution of the disc and includes dust extinction consistent with the dust properties derived from FIR observations. We also find naturally the stellar light eccess of the young sub-population near the midplane (hidden by the dust), which is required to heat the dust.
Distribution of Molecular Gas in Barred Spiral Galaxies
Authors: Kuno N. , Sato N. , Nakanishi H. , Hirota A. , Tosaki T. , Shioya Y. , Sorai K. , Nakai N. , Nishiyama K. , Vila-Vilaró B.
Published: April 2007

We made a CO(1 – 0) mapping survey of 40 nearby spiral galaxies with the Nobeyama 45-m telescope to provide useful data for detailed and systematic studies of molecular gas in the galaxies (Kuno et al. 2006). Using these data we have compared the distribution of molecular gas in barred and non-barred spirals and investigated the influence of the bar. We confirmed that the degree of the central concentration of molecular gas within the radial distances of the order of a bar length in barred spirals is significantly higher than that in non-barred spirals as shown by Sakamoto et al. (1999) and Sheth et al. (2005). This is contrast with the degree of the concentration of the total molecular gas mass within the radial distances of the order of the bar, which is similar for both barred and non-barred spirals. This implies that the bars appear to be efficient in driving gas that lies within their radial scales toward the center of the host galaxies, but that they play quite a smaller role at larger spatial scales on the disks. Thus the characteristic feature of the radial distribution of molecular gas seen in barred spirals, i.e. the strong intensity peaks at their centers, the shallow gradients within the bar regions or/and the secondary peaks at the radius of the bar-ends, can be explained by the accumulation of molecular gas within the bar regions. The accumulated gas by bars accounts for about half of molecular gas mass within the central region. We also found a correlation between the degree of central concentration of molecular gas and the bar strength. Galaxies with stronger bars tend to have higher central concentrations. The result indicates that stronger bar accumulate molecular gas toward the center more efficiently. The correlation between the degree of central concentration of molecular gas and the strength seems to be consistent with long-lived bars rather than short-lived ones which are destroyed by the gas accumulation toward the center many times in the Hubble time.
Globular Clusters in NGC 5128: The IMACS survey
Authors: Gómez M. , Geisler D. , Harris W. E. , Harris G. L. H. , Woodley K. A.
Published: April 2007

To extend our recent study of structural parameters of Globular Clusters (GCs) in the giant elliptical NGC 5128 (Gómez et al. 2006), we have obtained new high resolution images with the Magellan 6.5m at Las Campanas Observatory and the IMACS camera. Our images cover an area of 1.2 × 1.2 sq. degrees and have a seeing between 0.4 and 0.7'', thus making it possible to resolve a significant fraction of the GC population, which is now virtually entirely observed given the large spatial and magnitude range.

Convolution techniques allow us to find and to study the cluster candidates using the stellar PSF and analytical profiles for their light distribution. We therefore are able to derive structural parameters like size (effective and core radii), ellipticity, position angle and concentration. This is combined with the extensive database in the Washington photometric system by Harris et al. (2004) to select clusters according to shape, extendedness and Washington magnitudes and colours, which has proven very useful in discriminating GCs from foreground stars and background galaxies and for deriving metallicities.

Our first results for the central field (15'×15’) indicate that the GCs populate a large range of (MV, rh) parameter space, with typical sizes of Galactic GCs as well as much larger. Combined with our previous data, we find a continuum of clusters in this diagram, with no clear distinction between a variety of different ‘types’ often referred to, such as UCDs, Faint Fuzzies, etc.

In addition, a large fraction of GCs show a significant ellipticity whereas a paucity of round clusters is observed. We also confirm with a large (~250) sample that metal-rich clusters are smaller than metal-poor ones, which is in keeping with the general trend found in other galaxies. (e.g. Jordán et al. 2005)
The Build-up of the Colour-Magnitude Relation
Authors: Tanaka Masayuki , Kodama Tadayuki
Published: April 2007

We discuss the build-up of the colour-magnitude relation. The colour-magnitude relation first appears at the bright end and the faint end appears later. Interestingly, the build-up of colour-magnitude relation is delayed in low density environments. We suggest that galaxies follow the environment-dependent down-sizing evolution.
Dark Matter in NGC 2974
Authors: Weijmans A. , Krajnović D. , Oosterloo T. A. , Morganti R. , de Zeeuw P. T.
Published: April 2007

We present HI observations of the elliptical galaxy NGC 2974, obtained with the VLA. These observations reveal that the previously detected HI disc in this galaxy (Kim et al. 1988) is in fact a ring. Combining the flat rotation curve with the central kinematics of the ionised gas, obtained with the integral-field spectrograph SAURON, allows us to determine the mass-to-light ratio M/L as a function of radius, ranging from 100 pc in the centre to 10 kpc at the edges of the HI ring. A dark halo is required to explain the observed rotation: at the outer radii ~70% of the total mass is dark†.
The Red Halos of Galaxies
Authors: Zackrisson Erik , Bergvall Nils , Östlin Göran , Micheva Genoveva , Caldwell Brady
Published: April 2007

Optical and near-IR surface photometry of the halos of disk galaxies and blue compact galaxies have revealed a very red spectral energy distribution, which cannot easily be reconciled with any normal type of stellar population. Using spectral evolutionary models, we demonstrate that a stellar population with an extremely bottom-heavy initial mass function can explain the red halos of both types of objects. Because of its very high mass-to-light ratio, this halo population may account for some of the missing baryons in the local Universe.