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1

Lamarche, C., J. D. Smith, K. Kreckel, et al. "Direct Far-infrared Metal Abundances (FIRA). I. M101." Astrophysical Journal 925, no. 2 (2022): 194. http://dx.doi.org/10.3847/1538-4357/ac3b4f.

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Abstract Accurately determining gas-phase metal abundances within galaxies is critical as metals strongly affect the physics of the interstellar medium. To date, the vast majority of widely used gas-phase abundance indicators rely on emission from bright optical lines, whose emissivities are highly sensitive to the electron temperature. Alternatively, direct-abundance methods exist that measure the temperature of the emitting gas directly, though these methods usually require challenging observations of highly excited auroral lines. Low-lying far-infrared (FIR) fine structure lines are largely
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List Sánchez, Rurik H., and David W. Macdonald. "Carnivora atnd their larger mammalian prey species invenory and abundance in the Janos-Nuevo Casas Grandes praire dog complex, Chihuahua." Revista Mexicana de Mastozoología (Nueva Epoca) 3, no. 1 (2014): 95. http://dx.doi.org/10.22201/ie.20074484e.1998.3.1.62.

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Abstract. This study examined the carnivore species composition and abundance in the Janos-Nuevo Casas Grandes prairie dog complex of north-western Chihuahua, Mexico. Thirteen species of carnivores were recorded in habitats including prairie dog towns, grassland, mesquite scrub and riparian vegetation. From artificial scent-stations and spotlight transects the most abundant carnivore species appeared to be the kit fox Vulpes macrotis and the coyote Canis latrans. Striped/hooded skunks (Mephitis spp) and American badgers (Taxidea taxus) were also common. No significant differences were found be
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Sherman, CS, MR Heupel, SK Moore, A. Chin, and CA Simpfendorfer. "When sharks are away, rays will play: effects of top predator removal in coral reef ecosystems." Marine Ecology Progress Series 641 (May 7, 2020): 145–57. http://dx.doi.org/10.3354/meps13307.

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Shark abundances are decreasing on many coral reefs, but the ecosystem effects of this loss are poorly understood. Rays are a prevalent mesopredator in tropical coral reef ecosystems that are preyed upon by top predators like sharks. Studies have suggested reduced predator abundances lead to increases in mesopredator abundance (mesopredator release). We examined the relationship between top predator abundances and the abundance and behaviour of 2 small benthic ray genera using baited remote underwater video systems (BRUVS) across 6 countries. Where predators were more abundant, 2 genera of sma
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Roche, Kimberly E., and Sayan Mukherjee. "The accuracy of absolute differential abundance analysis from relative count data." PLOS Computational Biology 18, no. 7 (2022): e1010284. http://dx.doi.org/10.1371/journal.pcbi.1010284.

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Concerns have been raised about the use of relative abundance data derived from next generation sequencing as a proxy for absolute abundances. For example, in the differential abundance setting, compositional effects in relative abundance data may give rise to spurious differences (false positives) when considered from the absolute perspective. In practice however, relative abundances are often transformed by renormalization strategies intended to compensate for these effects and the scope of the practical problem remains unclear. We used simulated data to explore the consistency of differenti
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Dors, Oli L. "Chemical abundances in Seyfert galaxies – VI. Empirical abundance calibration." Monthly Notices of the Royal Astronomical Society 507, no. 1 (2021): 466–74. http://dx.doi.org/10.1093/mnras/stab2166.

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ABSTRACT We derived a bi-dimensional calibration between the emission-line ratios $R_{23}= ([\mathrm{ O}\, {\small {\rm II}}]\,\lambda 3726 +\lambda 3729 +[\mathrm{ O}\mathrm{ }\, {\small {\rm III}}]\,\lambda 4959 + \lambda 5007)/\rm H\,\beta$, ${\it P}=[([\mathrm{ O}\, {\small {\rm III}}]\,\lambda 4959+\lambda 5007)/{\rm H}\,\beta ]/R_{23}$ and the oxygen abundance relative to hydrogen (O/H) in the gas phase of Seyfert 1 and 2 nuclei. In view of this, emission-line intensity ratios for a sample of objects taken from the Sloan Digital Sky Survey Data Release 7 measured by the MPA/JHU group and
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Lizama, Maria de los Angeles Perez, Ricardo Massato Takemoto, and Gilberto Cezar Pavanelli. "Influence of the seasonal and environmental patterns and host reproduction on the metazoan parasites of Prochilodus lineatus." Brazilian Archives of Biology and Technology 49, no. 4 (2006): 611–22. http://dx.doi.org/10.1590/s1516-89132006000500011.

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One hundred and forty-eight specimens of Prochilodus lineatus (Valenciennes, 1836) were collected on the Upper Paraná River floodplain, Brazil. Kritskyia boegeri presented significant differences in the abundance according to the host stage of gonadal maturity. Ergasilus sp. presented negative correlation between the GSR of the females and parasite abundance. K. boegeri presented negative correlation between the GSR of the males and abundance. Tereancistrum curimba and Saccocoelioides magnorchis occurred in higher abundance in the open lagoons. Rhinonastes pseudocapsaloideum and S. nanii prese
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7

Richer, M. G., M. L. McCall, and N. Arimoto. "Oxygen Abundances in Diffuse Ellipticals and the Metallicity-Luminosity Relation for Dwarf Galaxies." Symposium - International Astronomical Union 171 (1996): 439. http://dx.doi.org/10.1017/s0074180900233573.

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Using theoretical models of the planetary nebula populations in galaxies, we investigate whether the current oxygen abundances in bright planetary nebulae can be used to predict the oxygen abundance that persisted in the interstellar medium when star formation stopped. In all galaxies, these models predict that a gap develops between the abundances observed in bright planetary nebulae and those that persisted in the interstellar medium when star formation stopped. This abundance gap depends primarily upon the oxygen abundance achieved in the interstellar medium when star formation stopped, tho
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8

Fabrizio, Mary C., Jonathan Raz, and Rajesh Ramanath Bandekar. "Using linear models with correlated errors to analyze changes in abundance of Lake Michigan fishes: 1973-1992." Canadian Journal of Fisheries and Aquatic Sciences 57, no. 4 (2000): 775–88. http://dx.doi.org/10.1139/f00-020.

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We examined annual changes in relative abundance of Lake Michigan fishes using linear models with correlated errors in space and time. Abundance of bloater (Coregonus hoyi), deepwater sculpin (Myoxocephalus thompsoni), slimy sculpin (Cottus cognatus), alewife (Alosa pseudoharengus), and rainbow smelt (Osmerus mordax) was monitored with bottom trawls at 10 discrete depths (between 18 and 110 m) off eight fixed ports from 1973 to 1992. The model describing abundance included fixed effects of year, port, depth, and interaction terms as well as quadratic and cubic effects of year and depth because
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9

Takada-Hidai, M. "Non-Magnetic Anomalous Stars: The Hg-Mn Stars — A Review of Elemental Abundances —." Symposium - International Astronomical Union 145 (1991): 137–47. http://dx.doi.org/10.1017/s0074180900227320.

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Abundance analyses of HgMn stars in these 15 years are compiled to clarify the abundance characteristics. NLTE abundance studies relevant to HgMn stars are also surveyed for the period of these 20 years. Discussions are made on influences of uncertainties in the atmospheric parameters and of NLTE effects upon abundance determinations, and further on establishment of abundances.
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10

Crozier, Gaea E., and Dale E. Gawlik. "Avian Response to Nutrient Enrichment in an Oligotrophic Wetland, the Florida Everglades." Condor 104, no. 3 (2002): 631–42. http://dx.doi.org/10.1093/condor/104.3.631.

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Abstract We studied the effects of nutrient enrichment on the bird community in an oligotrophic wetland, the Florida Everglades. Among the non-wading birds surveyed in 1996 and 1997, Boat-tailed Grackles (Quiscalus major) and Common Moorhens (Gallinula chloropus) were consistently more abundant in enriched sites, whereas Common Yellowthroats (Geothlypis trichas) were consistently more abundant in unenriched sites. The abundance of Red-winged Blackbird (Agelaius phoeniceus) was not significantly different between enriched and unenriched sites. Among wading birds, Wood Storks (Mycteria americana
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11

Mitro, Matthew G., Alexander V. Zale, and Bruce A. Rich. "The relation between age-0 rainbow trout (Oncorhynchus mykiss) abundance and winter discharge in a regulated river." Canadian Journal of Fisheries and Aquatic Sciences 60, no. 2 (2003): 135–39. http://dx.doi.org/10.1139/f03-006.

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We identified and experimentally tested a discharge–abundance relation that predicted, based on the mean river discharge in the second half of winter (15 January – 31 March), the spring abundance of age-0 rainbow trout (Oncorhynchus mykiss) in a section of the Henrys Fork of the Snake River, Idaho, with complex bank habitat. We also considered a competing hypothesis in which autumn abundance determined spring abundance. We established that large abundances of age-0 trout were present in autumn (34 000 – 81 000) and lower abundances remained in spring (8000 – 15 000). Winter loss of age-0 trout
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12

Monier, Richard. "The Abundances of Carbon, Sulfur, Scandium, Titanium, Manganese, Iron, Gallium and Strontium in the Atmosphere of HD144844." Research Notes of the AAS 7, no. 1 (2023): 10. http://dx.doi.org/10.3847/2515-5172/acb2cd.

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Abstract Abundances of manganese and gallium are derived in LTE for the B9 Mn P Ga star HD 144844 using the Mn ii lines at 4206.37 and 4259.19 Å and the Ga ii line at 6334.07 Å including hyperfine spliting and nuclear shifts. Both elements are found to be overabundant, about 7–10 times the manganese abundance, depending on the line of Mn ii used, and about 1800 times the solar gallium abundance. The synthesis of three Fe ii lines at 4258.15, 4273.33 and 4296.57 Å yields an abundance of iron marginally above the solar iron abundance. The synthesis of other lines in the range 4200 up to 4300 Å y
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13

Bengsen, Andrew, John Butler, and Pip Masters. "Estimating and indexing feral cat population abundances using camera traps." Wildlife Research 38, no. 8 (2011): 732. http://dx.doi.org/10.1071/wr11134.

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Context The ability to monitor changes in population abundance is critical to the success of pest animal management and research programs. Feral cats (Felis catus) are an important pest animal, but current monitoring techniques have limited sensitivity or are limited in use to particular circumstances or habitats. Recent advances in camera-trapping methods provide the potential to identify individual feral cats, and to use this information to estimate population abundances using capture–mark–recapture (CMR) methods. Aims Here, we use a manipulative study to test whether camera-trapping and CMR
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14

Matsushita, Kyoko, Yasushi Ikebe, Alexis Finoguenov, and Hans Böhringer. "XMM Observations of Abundances in the Intracluster Medium." Symposium - International Astronomical Union 217 (2004): 102–7. http://dx.doi.org/10.1017/s0074180900197220.

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Based on XMM-Newton observations of M 87 and the Centaurus cluster, abundance profiles of various elements of the intracluster medium (ICM) are derived. The abundances of Si and Fe show strong decreasing gradients. In contrast, the O and Mg abundances are about half of the Si abundance at the center.From the gas mass to stellar mass ratio and the comparison of Mg abundance with the stellar metallicity, the stellar mass loss from the central galaxies is indicated to be the main source of gas in the very central region of the clusters.The observed O, Si and Fe abundance pattern determines the co
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15

Su, Adrienne. "Abundance." Prairie Schooner 94, no. 4 (2020): 9–10. http://dx.doi.org/10.1353/psg.2020.0115.

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16

Downing, Raymond. "Abundance." Family Medicine 52, no. 2 (2020): 147–48. http://dx.doi.org/10.22454/fammed.2020.572733.

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17

Groff, Lauren. "Abundance." Ecotone 7, no. 2 (2012): 232–45. http://dx.doi.org/10.1353/ect.2012.0002.

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18

Barot, Rick. "Abundance." Yale Review 112, no. 2 (2024): 37–40. http://dx.doi.org/10.1353/tyr.2024.a936062.

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19

Giridhar, Sunetra. "Abundance Analysis of Alpha Ursae Minoris." International Astronomical Union Colloquium 82 (1985): 100–103. http://dx.doi.org/10.1017/s0252921100109224.

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AbstractWe have derived atmospheric abundances of the bright Cepheid a UMi in order to study the abundance anomalies in different elements. The atmospheric abundance of C, 0, Fe-peak elements Ca, Sc, Ti, Cr, Fe and heavier s-process elements Y, Ba, Ce and Sm have been derived using the method of spectrum synthesis. The abundance of carbon is derived using the C I lines in 4700A region, whereas for oxygen, the forbidden line at 6300.311A is employed. Abundances of the Fe-peak elements and s-process elements are obtained by synthesizing selected portions in the wavelength range 4330A - 4650A. Th
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Schöneberg, Nils. "The 2024 BBN baryon abundance update." Journal of Cosmology and Astroparticle Physics 2024, no. 06 (2024): 006. http://dx.doi.org/10.1088/1475-7516/2024/06/006.

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Abstract We revisit the state of the light element abundances from big bang nucleosynthesis in early 2024 with particular focus on the derived baryon abundance. We find that the largest differences between the final baryon abundances are typically driven by the assumed Deuterium burning rates, characterized in this work by the underlying code. The rates from theoretical ab-initio calculations favor smaller baryon abundances, while experimentally-determined rates prefer higher abundances. Through robust marginalization over a wide range of nuclear rates, the recently released PRyMordial code al
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21

Lou, Jun, Li Yang, Haizhen Wang, Laosheng Wu, and Jianming Xu. "Assessing soil bacterial community and dynamics by integrated high-throughput absolute abundance quantification." PeerJ 6 (March 14, 2018): e4514. http://dx.doi.org/10.7717/peerj.4514.

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Microbial ecological studies have been remarkably promoted by the high-throughput sequencing approach with explosive information of taxonomy and relative abundance. However, relative abundance does not reflect the quantity of the microbial community and the inter-sample differences among taxa. In this study, we refined and applied an integrated high-throughput absolute abundance quantification (iHAAQ) method to better characterize soil quantitative bacterial community through combining the relative abundance (by high-throughput sequencing) and total bacterial quantities (by quantitative PCR).
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22

Evans, Marlene S. "Large-Lake Responses to Declines in the Abundance of a Major Fish Planktivore—the Lake Michigan Example." Canadian Journal of Fisheries and Aquatic Sciences 47, no. 9 (1990): 1738–54. http://dx.doi.org/10.1139/f90-198.

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Alewife abundances declined dramatically in southeastern Lake Michigan over 1973–77, several years before the lakewide decline occurred. The regional effects of this decline on adult copepod abundances, zooplankton biomass, and water clarity are examined. In the offshore region, the two largest copepods, Limnocalanus macrurus and Diaptomus sicilis, increased in abundance during the mid-1970's, reflecting the decrease in alewife predation. Limnocalanus macrurus abundances declined in later years, reflecting increased prédation pressures from the increasing bloater population. The small-bodied D
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23

Pace, Michael L., Stephen B. Baines, Hélène Cyr, and John A. Downing. "Relationships among Early Life Stages of Morone americana and Morone saxatilis from Long-Term Monitoring of the Hudson River Estuary." Canadian Journal of Fisheries and Aquatic Sciences 50, no. 9 (1993): 1976–85. http://dx.doi.org/10.1139/f93-220.

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Annual abundances of eggs, yolk-sac larvae (YSL), post-yolk-sac larvae (PYSL), and young-of-the-year (YOY) stages of Morone americana and Morone saxatilis are summarized from a 17-yr monitoring program in the Hudson River Estuary. Variability in temperature and freshwater flow in the Hudson River explained little of the interannual variation of early life stages of either species. Year class strength as indicated by the abundance of early life stages does not appear to be strongly influenced by environmental conditions. YSL were positively related to the abundance of eggs, but these relationsh
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Wesson, R., D. Jones, J. García-Rojas, H. Boffin, and R. Corradi. "Close Binaries and the Abundance Discrepancy Problem in Planetary Nebulae." Galaxies 6, no. 4 (2018): 110. http://dx.doi.org/10.3390/galaxies6040110.

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Motivated by the recent establishment of a connection between central star binarity and extreme abundance discrepancies in planetary nebulae, we have carried out a spectroscopic survey targeting planetary nebula with binary central stars and previously unmeasured recombination line abundances. We have discovered seven new extreme abundance discrepancies, confirming that binarity is key to understanding the abundance discrepancy problem. Analysis of all 15 objects with a binary central star and a measured abundance discrepancy suggests a cut-off period of about 1.15 days, below which extreme ab
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Heiter, U., and R. E. Luck. "Abundance Analysis of Planetary Host Stars. I. Differential Iron Abundances." Astronomical Journal 126, no. 4 (2003): 2015–36. http://dx.doi.org/10.1086/378366.

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Rogers, Noah S. J., Evan D. Skillman, Richard W. Pogge, et al. "CHAOS. VII. A Large-scale Direct Abundance Study in M33." Astrophysical Journal 939, no. 1 (2022): 44. http://dx.doi.org/10.3847/1538-4357/ac947d.

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Abstract The dispersion in chemical abundances provides a very strong constraint on the processes that drive the chemical enrichment of galaxies. Due to its proximity, the spiral galaxy M33 has been the focus of numerous chemical abundance surveys to study the chemical enrichment and dispersion in abundances over large spatial scales. The CHemical Abundances Of Spirals project has observed ∼100 H ii regions in M33 with the Large Binocular Telescope (LBT), producing the largest homogeneous sample of electron temperatures (T e ) and direct abundances in this galaxy. Our LBT observations produce
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Ito, Hiroko, Wako Aoki, Satoshi Honda, Timothy C. Beers, and Nozomu Tominaga. "The 9th Magnitude CEMP star BD+44°493: Origin of its Carbon Excess and Beryllium Abundance." Proceedings of the International Astronomical Union 5, S265 (2009): 124–25. http://dx.doi.org/10.1017/s1743921310000360.

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AbstractWe performed a chemical abundance analysis of the very bright (V = 9.1) carbon-enhanced metal-poor (CEMP) star BD+44°493, which is the first star found with metallicity [Fe/H] < −3.5 and an apparent magnitude V < 12. The star is classified as a CEMP-no” subgiant, and its abundance pattern implies that a first-generation faint supernova is the most likely origin of its carbon excess. We set an very low upper limit on this star's beryllium abundance, which demonstrates that high C and O abundances do not necessarily imply high Be abundances.
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Hu, Xiaoyi, Te Jiang, Pei Ma, Hao Zhang, Paul Lucey, and Menghua Zhu. "A Spectral Library Study of Mixtures of Common Lunar Minerals and Glass." Remote Sensing 15, no. 8 (2023): 2195. http://dx.doi.org/10.3390/rs15082195.

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Reflectance spectroscopy is a powerful tool to remotely identify the mineral and chemical compositions of the lunar regolith. The lunar soils contain silicate minerals with prominent absorption features and glasses with much less distinctive spectral features. The accuracy of mineral abundance retrieval may be affected by the presence of glasses. In this work, we construct a spectral library of mixtures of major lunar-type minerals and synthetic glasses with varying relative abundances and test their performance on mineral abundance retrievals. By matching the library spectra with the spectra
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Santos-Peral, P., A. Recio-Blanco, P. de Laverny, E. Fernández-Alvar, and C. Ordenovic. "The AMBRE Project: Spectrum normalisation influence on Mg abundances in the metal-rich Galactic disc." Astronomy & Astrophysics 639 (July 2020): A140. http://dx.doi.org/10.1051/0004-6361/202037522.

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Context. The abundance of α-elements provides an important fossil signature in Galactic archaeology to trace the chemical evolution of the different disc populations. High-precision chemical abundances are crucial to improving our understanding of the chemodynamical properties present in the Galaxy. However, deriving precise abundance estimations in the metal-rich disc ([M/H] > 0 dex) is still challenging. Aims. The aim of this paper is to analyse different error sources affecting magnesium abundance estimations from optical spectra of metal-rich stars. Methods. We derived Mg abundances for
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Zhou, Qing, Xu-Chao Zhang, Zhi-Hong Chen, et al. "Relative Abundance of EGFR Mutations Predicts Benefit From Gefitinib Treatment for Advanced Non–Small-Cell Lung Cancer." Journal of Clinical Oncology 29, no. 24 (2011): 3316–21. http://dx.doi.org/10.1200/jco.2010.33.3757.

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Purpose Our aim was to determine whether abundance of epidermal growth factor receptor (EGFR) mutations in tumors predicts benefit from treatment with EGFR–tyrosine kinase inhibitors (TKIs) for advanced non–small-cell lung cancer (NSCLC). Patients and Methods We detected EGFR mutations in 100 lung cancer samples using direct DNA sequencing and amplification refractory mutation system (ARMS). Mutation-positive tumors by both methods carried high abundance of EGFR mutations. Tumors that were mutation positive by ARMS but mutation negative by direct DNA sequencing harbored low abundance of EGFR m
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Sit, Tawny, David H. Weinberg, Adam Wheeler, et al. "Chemical Cartography with APOGEE: Two-process Parameters and Residual Abundances for 288,789 Stars from Data Release 17." Astrophysical Journal 970, no. 2 (2024): 180. http://dx.doi.org/10.3847/1538-4357/ad4ed2.

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Abstract Stellar abundance measurements are subject to systematic errors that induce extra scatter and artificial correlations in elemental abundance patterns. We derive empirical calibration offsets to remove systematic trends with surface gravity log ( g ) in 17 elemental abundances of 288,789 evolved stars from the SDSS APOGEE survey. We fit these corrected abundances as the sum of a prompt process tracing core-collapse supernovae and a delayed process tracing Type Ia supernovae, thus recasting each star’s measurements into the amplitudes A cc and A Ia and the element-by-element residuals f
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Barbar, Facundo, Gonzalo O. Ignazi, Fernando Hiraldo, and Sergio A. Lambertucci. "Exotic lagomorph may influence eagle abundances and breeding spatial aggregations: a field study and meta-analysis on the nearest neighbor distance." PeerJ 6 (May 10, 2018): e4746. http://dx.doi.org/10.7717/peerj.4746.

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The introduction of alien species could be changing food source composition, ultimately restructuring demography and spatial distribution of native communities. In Argentine Patagonia, the exotic European hare has one of the highest numbers recorded worldwide and is now a widely consumed prey for many predators. We examine the potential relationship between abundance of this relatively new prey and the abundance and breeding spacing of one of its main consumers, the Black-chested Buzzard-Eagle (Geranoaetus melanoleucus). First we analyze the abundance of individuals of a raptor guild in relati
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Reggiani, Henrique, Kevin C. Schlaufman, Brian F. Healy, Joshua D. Lothringer, and David K. Sing. "Evidence that the Hot Jupiter WASP-77 A b Formed Beyond Its Parent Protoplanetary Disk’s H2O Ice Line." Astronomical Journal 163, no. 4 (2022): 159. http://dx.doi.org/10.3847/1538-3881/ac4d9f.

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Abstract Idealized protoplanetary disk and giant planet formation models have been interpreted to suggest that a giant planet’s atmospheric abundances can be used to infer its formation location in its parent protoplanetary disk. It has recently been reported that the hot Jupiter WASP-77 A b has subsolar atmospheric carbon and oxygen abundances with a solar C/O abundance ratio. Assuming solar carbon and oxygen abundances for its host star WASP-77 A, WASP-77 A b’s atmospheric carbon and oxygen abundances possibly indicate that it accreted its envelope interior to its parent protoplanetary disk’
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Bartel, Rebecca A., and Frederick F. Knowlton. "Functional feeding responses of coyotes, Canis latrans, to fluctuating prey abundance in the Curlew Valley, Utah, 1977–1993." Canadian Journal of Zoology 83, no. 4 (2005): 569–78. http://dx.doi.org/10.1139/z05-039.

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We investigated interactions between coyotes (Canis latrans Say, 1823) and prey in the Curlew Valley, Utah, by comparing prey abundances with prey consumption rates. Previous studies reported a cyclic trend in black-tailed jackrabbit (Lepus californicus Gray, 1837) density with a period of 10 years and >150-fold amplitude, as well as short-term fluctuations among some rodent species that exceeded an 8-fold difference in amplitude over 2 years. Our results suggest changes in coyote diets mainly reflect the fluctuations in jackrabbit abundance. Prey switching to rodents during periods of low
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Wesson, R., D. Jones, J. García-Rojas, R. L. M. Corradi, and H. M. J. Boffin. "Close binary central stars and the abundance discrepancy - new extreme objects." Proceedings of the International Astronomical Union 12, S323 (2016): 70–73. http://dx.doi.org/10.1017/s1743921317001958.

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AbstractRecent work (Corradi et al. 2015; Jones et al. 2016) has shown that the phenomenon of extreme abundance discrepancies, where recombination line abundances exceed collisionally excited line abundances by factors of 10 or more, seem to be strongly associated with planetary nebulae with close binary central stars. To further investigate, we have obtained spectra of a sample of nebulae with known close binary central stars, using FORS2 on the VLT, and we have discovered several new extreme abundance discrepancy objects. We did not find any non-extreme discrepancies, suggesting that a very
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Daflon, Simone, Katia Cunha, Ramiro de la Reza, Jon Holtzman, and Cristina Chiappini. "Sulfur Abundances in Orion B Stars." Proceedings of the International Astronomical Union 5, S265 (2009): 358–59. http://dx.doi.org/10.1017/s1743921310000918.

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AbstractSulfur abundances are derived for a sample of ten B MS star members of the Orion association. The analysis is based on LTE model atmospheres and non-LTE line formation theory by means of spectrum synthesis analysis of Sii and Siii lines. The abundance distribution obtained for the Orion targets is homogeneous within the errors in the analysis: A(S)=7.15±0.05. This abundance result is in agreement with the solar value and with results for the Orion nebula. The sulfur abundances for Orion combined with previous results for other OB-type stars produce a relatively shallow sulfur abundance
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Buen, Lorena López-de, and Juan Francisco Ornelas. "Frugivorous birds, host selection and the mistletoe Psittacanthus schiedeanus, in central Veracruz, Mexico." Journal of Tropical Ecology 15, no. 3 (1999): 329–40. http://dx.doi.org/10.1017/s0266467499000851.

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Frugivorous birds play an important role in parasitic mistletoe transmission among host species. The foraging behaviour and host selection of Psittacanthus schiedeanus mistletoe fruit-eating birds was studied in cloud forest remnants in Central Veracruz, México. Cedar waxwings, Bombycilla cedrorum, gray silky-flycatchers, Ptilogonys cinereus, and social flycatchers, Myiozetetes similis, eating ripe whole mistletoe fruits and defecating or regurgitating the seeds were observed. That variation in host species selection by frugivorous birds had a direct effect on mistletoe dispersion was hypothes
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Ito, Hiroko, Wako Aoki, Satoshi Honda, Timothy C. Beers, and Nozomu Tominaga. "A very low upper limit for a Be abundance of a carbon-enhanced metal-poor star." Proceedings of the International Astronomical Union 5, S268 (2009): 337–38. http://dx.doi.org/10.1017/s1743921310004369.

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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.
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39

Milingo, Jacquelynne B., Richard B. C. Henry, and Karen B. Kwitter. "Sulfur, Chlorine & Argon Abundances in a Southern Sample of Planetary Nebulae." Symposium - International Astronomical Union 209 (2003): 375. http://dx.doi.org/10.1017/s0074180900209066.

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We present S/O, Cl/O, and Ar/O abundance ratios for 45 predominantly Type II southern PNe. These abundances are based upon line strengths from newly acquired spectrophotometry covering an extended optical range from 3600 - 9600 Å. The following average abundance ratios were obtained from this sample: S/O=0.011±0.0064, Cl/O=0.00031±0.00012, and Ar/O=0.0051±0.0020. This study, together with a sample of northern PNe, is aimed at producing a large homogeneous set of observations and abundances. Specifically, we are addressing the lack of homogeneously observed, reduced, and analyzed data sets that
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Irvine, James R., and Masa-aki Fukuwaka. "Pacific salmon abundance trends and climate change." ICES Journal of Marine Science 68, no. 6 (2011): 1122–30. http://dx.doi.org/10.1093/icesjms/fsq199.

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Abstract Irvine, J. R., and Fukuwaka, M. 2011. Pacific salmon abundance trends and climate change. – ICES Journal of Marine Science, 68: 1122–1130. Understanding reasons for historical patterns in salmon abundance could help anticipate future climate-related changes. Recent salmon abundance in the northern North Pacific Ocean, as indexed by commercial catches, has been among the highest on record, with no indication of decline; the 2009 catch was the highest to date. Although the North Pacific Ocean continues to produce large quantities of Pacific salmon, temporal abundance patterns vary among
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Fuente, Asunción. "Gas phase Elemental abundances in Molecular cloudS (GEMS)." EPJ Web of Conferences 265 (2022): 00005. http://dx.doi.org/10.1051/epjconf/202226500005.

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Gas phase Elemental abundances in Molecular CloudS (GEMS) is an IRAM 30m Large Program aimed at determining the elemental abundances of carbon (C), oxygen (O), nitrogen (N), and sulphur (S) in a selected set of prototypical star forming filaments. Elemental abundances have a key role in the star formation process by driving the gas cooling rate and the gas ionization degree. Defining elemental abundance as the amount of a given atom in volatiles, the elemental abundances of C, O, and N in the interstellar medium are currently known within a factor of a few. However, the elemental abundance of
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42

Marino, R. A., F. F. Rosales-Ortega, F. Sánchez, and A. Gil de Paz. "New empirical metallicity calibrations: Joint analysis of CALIFA data and literature Te-based measurements." Proceedings of the International Astronomical Union 10, S309 (2014): 328. http://dx.doi.org/10.1017/s1743921314010229.

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AbstractIn Marino et al. (2013) we provide revisited empirical calibrations for the oxygen abundances in HII regions based on the O3N2 and N2 indicators. This work is based on the most comprehensive compilation of both Te-based and multiple strong-line (ONS-based) ionized-gas abundance measurements in external galaxies to date in terms of all statistical significance, quality, and coverage of the parameters space. Our dataset compiles the Te-based abundances of 603 HII regions extracted from the literature but also includes new measurements from the CALIFA survey. We also present a comparison
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43

Susmitha, A., D. K. Ojha, T. Sivarani, et al. "Optical and NIR spectroscopy of cool CEMP stars to probe the nucleosynthesis in low-mass AGB binary system." Monthly Notices of the Royal Astronomical Society 506, no. 2 (2021): 1962–77. http://dx.doi.org/10.1093/mnras/stab1508.

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ABSTRACT We present the abundance analyses of seven carbon enhanced metal-poor (CEMP) stars to understand the origin of carbon in them. We used high-resolution optical spectra to derive abundances of various elements. We also used low-resolution near-infrared (NIR) spectra to derive the abundance of O and 12C/13C from the CO molecular band and compared their values with those derived from high-resolution optical spectra. We identified a good agreement between the values. Thus, in cool CEMP stars, the NIR observations complement the high-resolution optical observations to derive the oxygen abun
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Shah, Shivani P., Rana Ezzeddine, Alexander P. Ji, et al. "Uranium Abundances and Ages of r-process Enhanced Stars with Novel U ii Lines*." Astrophysical Journal 948, no. 2 (2023): 122. http://dx.doi.org/10.3847/1538-4357/acb8af.

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Abstract The ages of the oldest stars shed light on the birth, chemical enrichment, and chemical evolution of the universe. Nucleocosmochronometry provides an avenue to determining the ages of these stars independent from stellar-evolution models. The uranium abundance, which can be determined for metal-poor r-process enhanced (RPE) stars, has been known to constitute one of the most robust chronometers known. So far, U abundance determination has used a single U ii line at λ3859 Å. Consequently, U abundance has been reliably determined for only five RPE stars. Here, we present the first homog
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Duff, Thomas J., Tina L. Bell, and Alan York. "Patterns of plant abundances in natural systems: is there value in modelling both species abundance and distribution?" Australian Journal of Botany 59, no. 8 (2011): 719. http://dx.doi.org/10.1071/bt11017.

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In plant ecology it is common to use biophysical models to predict species distribution; however, spatial quantitative models of plant species remain rare. In practice, occupancy models are often assumed to indicate habitant quality and are used as surrogate abundance models. This study assessed the potential value of quantitative models of plants for ecosystem management applications by assessing patterns of occupancy and abundance within two closely related understorey plant species, Xanthorrhoea australis and X. caespitosa. Vegetation quadrats were surveyed in Eucalyptus woodland and cover-
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Hernández-Sánchez, Alejandro, and Antonio Santos-Moreno. "Availability of alternative prey rather than intraguild interactions determines the local abundance of two understudied and threatened small carnivore species." PLOS ONE 19, no. 11 (2024): e0310021. http://dx.doi.org/10.1371/journal.pone.0310021.

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Intraguild interactions influence the structure and local dynamics of carnivore mammals’ assemblages. The potential effects of these interactions are often determined by the body size of competing members and may result in negative relationships in their abundance and, ultimately, lead to species exclusion or coexistence. The relative importance of interspecific interactions along with landscape characteristics in determining population patterns of understudied and threatened sympatric small carnivores, such as skunks, remains poorly documented. Therefore, we assessed the spatiotemporal variat
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Reijniers, Jonas, Mike Begon, Vladimir S. Ageyev, and Herwig Leirs. "Plague epizootic cycles in Central Asia." Biology Letters 10, no. 6 (2014): 20140302. http://dx.doi.org/10.1098/rsbl.2014.0302.

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Infection thresholds, widely used in disease epidemiology, may operate on host abundance and, if present, on vector abundance. For wildlife populations, host and vector abundances often vary greatly across years and consequently the threshold may be crossed regularly, both up- and downward. Moreover, vector and host abundances may be interdependent, which may affect the infection dynamics. Theory predicts that if the relevant abundance, or combination of abundances, is above the threshold, then the infection is able to spread; if not, it is bound to fade out. In practice, though, the observed
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Gratton, Raffaele G. "Recent Advances in High Dispersion Spectroscopy of Globular Cluster Stars." Symposium - International Astronomical Union 132 (1988): 525–30. http://dx.doi.org/10.1017/s0074180900035610.

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The use CCD detectors has allowed a major progress in abundance derivations for globular cluster stars in the last years. Abundances deduced from high dispersion spectra now correlates well with other abundance indicators. I discuss some problems concerning the derivation of accurate metal abundances for globular clusters using high dispersion spectra from both the old photographic and the most recent CCD data. The discrepant low abundances found by Cohen (1980), from photographic material for M71 giants, are found to be due to the use of too high microturbulences.
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Cottrell, P. L. "Abundance analyses: methods, results and implications." Symposium - International Astronomical Union 118 (1986): 413–24. http://dx.doi.org/10.1017/s0074180900151794.

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The methods by which abundance analyses can be undertaken, especially with the growing use of high quantum efficiency digital detectors, are reviewed. The importance of the differential curve of growth technique is discussed, followed by a review of some recent results involving both late-type dwarf and giant stars. These include (1) the F and G dwarf abundance analyses of the elements sodium through nickel, which show an important differentiation between stars belonging to the young and old disk populations, (2) the possibility that departures from local thermodynamic equilibrium can effect s
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Zurita, A., E. Florido, F. Bresolin, E. Pérez-Montero, and I. Pérez. "Bar effect on gas-phase abundance gradients. I. Data sample and chemical abundances." Monthly Notices of the Royal Astronomical Society 500, no. 2 (2020): 2359–79. http://dx.doi.org/10.1093/mnras/staa2246.

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ABSTRACT Studies of gas-phase radial metallicity profiles in spirals published in the last decade have diminished the importance of galactic bars as agents that mix and flatten the profiles, contradicting results obtained in the 1990s. We have collected a large sample of 2831 published H ii region emission-line fluxes in 51 nearby galaxies, including objects both with and without the presence of a bar, with the aim of revisiting the issue of whether bars affect the radial metal distribution in spirals. In this first paper of a series of two, we present the galaxy and the H ii region samples. T
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