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The DEIMOS spectrograph has now been installed on the Keck-II telescope and commissioning is nearly complete. The DEEP2 Redshift Survey, which will take approximately 120 nights at the Keck Observatory over a three year period and has been designed to utilize the power of DEIMOS, began in the summer of 2002. The multiplexing power and high efficiency of DEIMOS enables us to target 1000 faint galaxies per clear night. Our goal is to gather high-quality spectra of ≈ 60,000 galaxies with z > 0.75 in order to study the properties and large scale clustering of galaxies at z ≈ 1. The survey will be executed at high spectral resolution, R = λ/δλ ≈ 5000, allowing us to work between the bright OH sky emission lines and to infer linewidths for many of the target galaxies (for several thousand objects, we will obtain rotation curves as well). The linewidth data will facilitate the execution of the classical redshift-volume cosmological test, which can provide a precision measurement of the equation of state of the Universe. This talk reviews the project, summarizes our science goals and presents some early DEIMOS data.

We identified a sample of 58 candidate stars with metallicity [Fe/H] ≲ −0.8 that likely belong to the old bulge spheroid stellar population, and analyse their Na and Al abundances from Apache Point Observatory Galactic Evolution Experiment (APOGEE) spectra. In a previous work, we inspected APOGEE-Stellar Parameter and Chemical Abundance Pipeline abundances of C, N, O, Mg, Al, Ca, Si, and Ce in this sample. Regarding Na lines, one of them appears very strong in about 20 per cent of the sample stars, but it is not confirmed by other Na lines, and can be explained by sky lines, which affect the reduced spectra of stars in a certain radial velocity range. The Na abundances for 15 more reliable cases were taken into account. Al lines in the H band instead appear to be very reliable. Na and Al exhibit a spread in abundances, whereas no spread in N abundances is found, and we found no correlation between them, indicating that these stars could not be identified as second-generation stars that originated in globular clusters. We carry out the study of the behaviour of Na and Al in our sample of bulge stars and literature data by comparing them with chemodynamical evolution model suitable for the Galactic bulge. The Na abundances show a large spread, and the chemodynamical models follow the main data, whereas for aluminum instead, the models reproduce very satisfactorily the nearly secondary-element behaviour of aluminum in the metallicity range below [Fe/H] ≲ −1.0. For the lower-metallicity end ([Fe/H < −2.5), hypernovae are assumed to be the main contributor to yields. [ABSTRACT FROM AUTHOR]

The APOGEE Open Cluster Chemical Abundances and Mapping survey is used to probe the chemical evolution of the s-process element cerium in the Galactic disk. Cerium abundances were derived from measurements of Ce ii lines in the APOGEE spectra using the Brussels Automatic Code for Characterizing High Accuracy Spectra in 218 stars belonging to 42 open clusters. Our results indicate that, in general, for ages < 4 Gyr, younger open clusters have higher [Ce/Fe] and [Ce/α-element] ratios than older clusters. In addition, metallicity segregates open clusters in the [Ce/X]–age plane (where X can be H, Fe, or the α-elements O, Mg, Si, or Ca). These metallicity-dependent relations result in [Ce/Fe] and [Ce/α] ratios with ages that are not universal clocks. Radial gradients of [Ce/H] and [Ce/Fe] ratios in open clusters, binned by age, were derived for the first time, with d[Ce/H]/dRGC being negative, while d[Ce/Fe]/dRGC is positive. [Ce/H] and [Ce/Fe] gradients are approximately constant over time, with the [Ce/Fe] gradient becoming slightly steeper, changing by ∼+0.009 dex kpc−1 Gyr−1. Both the [Ce/H] and [Ce/Fe] gradients are shifted to lower values of [Ce/H] and [Ce/Fe] for older open clusters. The chemical pattern of Ce in open clusters across the Galactic disk is discussed within the context of s-process yields from asymptotic giant branch (AGB) stars, gigayear time delays in Ce enrichment of the interstellar medium, and the strong dependence of Ce nucleosynthesis on the metallicity of its AGB stellar sources. [ABSTRACT FROM AUTHOR]

The Milky Way provides an ideal laboratory to test our understanding of galaxy evolution, owing to our ability to observe our Galaxy over fine scales. However, connecting the Galaxy to the wider galaxy population remains difficult, due to the challenges posed by our internal perspective and to the different observational techniques employed. Here, we present a sample of galaxies identified as Milky Way analogues on the basis of their stellar masses and bulge-to-total ratios, observed as part of the Mapping Nearby Galaxies at Apache Point Observatory survey. We analyse the galaxies in terms of their stellar kinematics and populations as well as their ionized gas contents. We find our sample to contain generally young stellar populations in their outskirts. However, we find a wide range of stellar ages in their central regions, and we detect central active galactic nucleus-like or composite-like activity in roughly half of the sample galaxies, with the other half consisting of galaxies with central star-forming emission or emission consistent with old stars. We measure gradients in gas metallicity and stellar metallicity that are generally flatter in physical units than those measured for the Milky Way; however, we find far better agreement with the Milky Way when scaling gradients by galaxies' disc scale lengths. From this, we argue much of the discrepancy in metallicity gradients to be due to the relative compactness of the Milky Way, with differences in observing perspective also likely to be a factor. [ABSTRACT FROM AUTHOR]

We present an elemental abundance analysis of high-resolution spectra for five giant stars spatially located within the innermost regions of the bulge globular cluster NGC 6522 and derive Fe, Mg, Al, C, N, O, Si, and Ce abundances based on H-band spectra taken with the multi-object APOGEE-north spectrograph from the SDSS-IV Apache Point Observatory Galactic Evolution Experiment (APOGEE) survey. Of the five cluster candidates, two previously unremarked stars are confirmed to have second-generation (SG) abundance patterns, with the basic pattern of depletion in C and Mg simultaneous with enrichment in N and Al as seen in other SG globular cluster populations at similar metallicity. In agreement with the most recent optical studies, the NGC 6522 stars analyzed exhibit (when available) only mild overabundances of the s-process element Ce, contradicting the idea that NGC 6522 stars are formed from gas enriched by spinstars and indicating that other stellar sources such as massive AGB stars could be the primary polluters of intra-cluster medium. The peculiar abundance signatures of SG stars have been observed in our data, confirming the presence of multiple generations of stars in NGC 6522. [ABSTRACT FROM AUTHOR]

We present a combination of high-resolution Hubble Space Telescope and wide-field ground-based and Galaxy Evolution Explorer data of the Galactic globular clusterM10 (NGC 6254).By using this large data set,we determined the center of gravity of the cluster and we built its density profile from star counts over its entire radial extension. We find that the density profile is well reproduced by a single-mass King model with structural parameters c = 1.41 and rc = 41". We also studied the blue straggler star (BSS) population and its radial distribution. We count a total number of 120 BSS within the tidal radius. Their radial distribution is bimodal: highly peaked in the cluster center, decreasing at intermediate distances, and rising again outward. We discuss these results in the context of the dynamical clock scheme presented by Ferraro et al. and of recent results about the radial distribution of binary systems in this cluster. [ABSTRACT FROM AUTHOR]

Emergency contraception (EC) is used post-coitally and offers women an important second chance to prevent pregnancy. Approximately 10 years ago, Mexico became one of the earliest countries working to expand EC access. Partners came together to pursue a synergistic four-pronged strategy, including product registration, health care provider training and orientation, awareness raising among the general public, and policy change. By 2006, five EC products were registered and sold in Mexico, EC was widely available through pharmacies and included in the public sector contraceptive options, and knowledge of the method had increased substantially. [ABSTRACT FROM AUTHOR]

The DEEP2 and COMBO-17 surveys are compared to study luminosity functions of red and blue galaxies to z ~ 1. The two surveys have different methods and sensitivities, but nevertheless results agree. After z ~ 1, Mimg1.gif has dimmed by 1.2-1.3 mag for all colors of galaxies, phgr* for blue galaxies has hardly changed, and phgr* for red galaxies has at least doubled (our formal value is ~0.5 dex). Luminosity density jB has fallen by 0.6 dex for blue galaxies but has remained nearly constant for red galaxies. These results imply that the number and total stellar mass of blue galaxies have been substantially constant since z ~ 1, whereas those of red galaxies (near L*) have been significantly rising. To explain the new red galaxies, a ``mixed'' scenario is proposed in which star formation in blue cloud galaxies is quenched, causing them to migrate to the red sequence, where they merge further in a small number of stellar mergers. This mixed scenario matches the local boxy-disky transition for nearby ellipticals, as well as red sequence stellar population scaling laws such as the color-magnitude and Mg-σ relations (which are explained as fossil relics from blue progenitors). Blue galaxies enter the red sequence via different quenching modes, each of which peaks at a different characteristic mass and time. The red sequence therefore likely builds up in different ways at different times and masses, and the concept of a single process that is ``downsizing'' (or upsizing) probably does not apply. Our claim in this paper of a rise in the number of red galaxies applies to galaxies near L*. Accurate counts of brighter galaxies on the steep part of the Schechter function require more accurate photometry than is currently available., Astronomy

Complications from abortive events are difficult to measure and compare across settings due to lack of standardized definitions, limited available data, and stigma. Globally, indirect methods are used to estimate the incidence of abortion complications by using provider reports as a proxy; however, few studies rely on clinical data for abortive event complications. Several studies show that many abortion clients seek PAC for reasons other than a complication such as confirmation of a complete abortion. We describe care-seeking for abortive events and complication rates over time (2018–2022) and by state from the Mexican public hospital discharge register. We used hospital discharge data from Mexico (called SAEH). We included hospital facilities operated by national and state ministries of health; since our focus is on complications (rather than incidence), we include only hospitals, where complications are treated. We included ICD-10 codes O02-O08 and Z303. Our primary outcome is the existence of a complication and details about type of complication. Complications reported include codes for excessive bleeding, infection, embolism, and unspecified. We also identified procedure type (aspiration, curettage, misoprostol). We included additional socio-demographic and clinical information available in the discharge record. We described patient characteristics, complications, and procedure type by year (2018-2022). We calculated state-level abortion complication rates (complications per 1,000 events) and created a heat map of the rate of abortion complications by state. We included 399,405 patients who received hospital-based care for an abortive event between 2018-2022. Patient demographic characteristics were stable over time (2018-2022). Overall, the largest age category was 20-24 years old (27%) and 2.5% of patients spoke an indigenous language. Abortive events primarily occurred at or less than 13 weeks of gestation (74% overall) and this proportion increased slightly over time from 73% in 2018 to 77% in 2022. Of all the patients who received care for abortive events, the overwhelming majority (93%) had no complication recorded and was stable over time. Of the 6-8% of patients who did experience a complication, the most common designation was "unspecified" with 6% of abortive events in 2018-2020; 5.6 % in 2021 and 3.9% in 2022. Reports of excessive bleeding, embolism, and infections were between <0.1-1% for all years. The states with higher complication rates are located primarily in the central and southern regions. The proportion of cases that were treated using curettage decreased from 55% in 2018 to 46% in 2022; the use of aspiration increased over time from 22% in 2018 to 29% in 2022, and use of misoprostol was less than 2% of cases overall. In Mexico, most patients who seek care for abortive events (induced, spontaneous, or post-abortion) in Ministry of Health hospitals have no complications. Curettage remains common and misoprostol is underutilized in the hospital setting in Mexico. Conflating care-seeking and complications overestimates of the risk of abortion. [ABSTRACT FROM AUTHOR]

We present a cautionary study characterizing the influence of non-solar abundance ratios on Hδ derived ages in the integrated light of early-type galaxies. We measure Hδ using a variety of index measurements designed to assess contamination from CN molecular lines in and around the Hδ feature. We propose that neighboring CN lines have a strong effect on continuum levels and the Hδ feature itself, thereby leading to a difficulty in designing an accurate Hδ index definition in populations with C andor N non-solar abundance ratios with population synthesis models that do not account for such variations. [ABSTRACT FROM PUBLISHER]

Abstract Background The deep-sea bacterium Photobacterium profundum is an established model for studying high pressure adaptation. In this paper we analyse the parental strain DB110 and the toxR mutant TW30 by massively parallel cDNA sequencing (RNA-seq). ToxR is a transmembrane DNA-binding protein first discovered in Vibrio cholerae, where it regulates a considerable number of genes involved in environmental adaptation and virulence. In P. profundum the abundance and activity of this protein is influenced by hydrostatic pressure and its role is related to the regulation of genes in a pressure-dependent manner. Results To better characterize the ToxR regulon, we compared the expression profiles of wt and toxR strains in response to pressure changes. Our results revealed a complex expression pattern with a group of 22 genes having expression profiles similar to OmpH that is an outer membrane protein transcribed in response to high hydrostatic pressure. Moreover, RNA-seq allowed a deep characterization of the transcriptional landscape that led to the identification of 460 putative small RNA genes and the detection of 298 protein-coding genes previously unknown. We were also able to perform a genome-wide prediction of operon structure, transcription start and termination sites, revealing an unexpected high number of genes (992) with large 5′-UTRs, long enough to harbour cis-regulatory RNA structures, suggesting a correlation between intergenic region size and UTR length. Conclusion This work led to a better understanding of high-pressure response in P. profundum. Furthermore, the high-resolution RNA-seq analysis revealed several unexpected features about transcriptional landscape and general mechanisms of controlling bacterial gene expression.