| 1. |
- Abolfathi, Bela, et al.
(författare)
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The Fourteenth Data Release of the Sloan Digital Sky Survey : First Spectroscopic Data from the Extended Baryon Oscillation Spectroscopic Survey and from the Second Phase of the Apache Point Observatory Galactic Evolution Experiment
- 2018
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Ingår i: Astrophysical Journal Supplement Series. - : IOP Publishing Ltd. - 0067-0049 .- 1538-4365. ; 235:2
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Tidskriftsartikel (refereegranskat)abstract
- The fourth generation of the Sloan Digital Sky Survey (SDSS-IV) has been in operation since 2014 July. This paper describes the second data release from this phase, and the 14th from SDSS overall (making this Data Release Fourteen or DR14). This release makes the data taken by SDSS-IV in its first two years of operation (2014-2016 July) public. Like all previous SDSS releases, DR14 is cumulative, including the most recent reductions and calibrations of all data taken by SDSS since the first phase began operations in 2000. New in DR14 is the first public release of data from the extended Baryon Oscillation Spectroscopic Survey; the first data from the second phase of the Apache Point Observatory (APO) Galactic Evolution Experiment (APOGEE-2), including stellar parameter estimates from an innovative data-driven machine-learning algorithm known as "The Cannon"; and almost twice as many data cubes from the Mapping Nearby Galaxies at APO (MaNGA) survey as were in the previous release (N = 2812 in total). This paper describes the location and format of the publicly available data from the SDSS-IV surveys. We provide references to the important technical papers describing how these data have been taken (both targeting and observation details) and processed for scientific use. The SDSS web site (www.sdss.org) has been updated for this release and provides links to data downloads, as well as tutorials and examples of data use. SDSS-IV is planning to continue to collect astronomical data until 2020 and will be followed by SDSS-V.
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| 2. |
- Blanton, Michael R., et al.
(författare)
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Sloan Digital Sky Survey IV : Mapping the Milky Way, Nearby Galaxies, and the Distant Universe
- 2017
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Ingår i: Astronomical Journal. - : IOP Publishing Ltd. - 0004-6256 .- 1538-3881. ; 154:1
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Tidskriftsartikel (refereegranskat)abstract
- We describe the Sloan Digital Sky Survey IV (SDSS-IV), a project encompassing three major spectroscopic programs. The Apache Point Observatory Galactic Evolution Experiment 2 (APOGEE-2) is observing hundreds of thousands of Milky Way stars at high resolution and. high signal-to-noise ratios in the near-infrared. The Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) survey is obtaining spatially resolved spectroscopy for thousands of nearby galaxies (median z similar to 0.03). The extended Baryon Oscillation Spectroscopic Survey (eBOSS) is mapping the galaxy, quasar, and neutral gas distributions between z similar to 0.6 and 3.5 to constrain cosmology using baryon acoustic oscillations, redshift space distortions, and the shape of the power spectrum. Within eBOSS, we are conducting two major subprograms: the SPectroscopic IDentification of eROSITA Sources (SPIDERS), investigating X-ray AGNs. and galaxies in X-ray clusters, and the Time Domain Spectroscopic Survey (TDSS), obtaining spectra of variable sources. All programs use the 2.5 m Sloan Foundation Telescope at the. Apache Point Observatory; observations there began in Summer 2014. APOGEE-2 also operates a second near-infrared spectrograph at the 2.5 m du Pont Telescope at Las Campanas Observatory, with observations beginning in early 2017. Observations at both facilities are scheduled to continue through 2020. In keeping with previous SDSS policy, SDSS-IV provides regularly scheduled public data releases; the first one, Data Release 13, was made available in 2016 July.
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| 3. |
- Haririan, Hady, et al.
(författare)
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Microbial analysis of subgingival plaque samples compared to that of whole saliva in patients with periodontitis
- 2014
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Ingår i: Journal of Periodontology. - : John Wiley & Sons. - 0022-3492 .- 1943-3670. ; 85:6, s. 819-828
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: The detection of special bacterial species in patients with periodontitis is considered to be useful for clinical diagnosis and treatment. The collection of subgingival plaque samples is the common way for the determination of periodontopathic bacteria. However, recently, salivary analysis has been discussed as an advantageous future diagnostic method for periodontitis because it offers simple quantitative sampling and the possibility to assess various bacteria. The aim of this cross-sectional study is to investigate whether there is a correlation between the results of different bacterial species in saliva and subgingival plaque samples from individuals with aggressive periodontitis (AgP) and chronic periodontitis (CP). METHODS: Whole saliva and subgingival plaque samples from the deepest pocket of each quadrant were collected from 43 patients with CP and 33 patients with AgP. Twenty different bacterial species from both samplings were determined by the 16S ribosomal RNA-based polymerase chain reaction with microarray technique. RESULTS: All bacterial species were detected in salivary and subgingival plaque samples. For Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Treponema denticola, and Tannerella forsythia, as well as Actinomyces viscosus, Campylobacter rectus/showae, Prevotella intermedia, Parvimonas micra, Eubacterium nodatum, and Campylobacter gracilis, a significant positive correlation between salivary and subgingival plaque samples was detected in patients with both types of periodontitis. There were no significant differences in bacteria in salivary and subgingival plaque samples between AgP and CP. CONCLUSION: Salivary analysis might be discussed as a potential alternative to subgingival plaque sampling for microbiologic analysis in both AgP and CP.
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| 4. |
- Laky, Markus, et al.
(författare)
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Serum levels of 25-hydroxyvitamin D are associated with periodontal disease
- 2017
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Ingår i: Clinical Oral Investigations. - : Springer. - 1432-6981 .- 1436-3771. ; 21:5, s. 1553-1558
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Tidskriftsartikel (refereegranskat)abstract
- Objectives Vitamin D plays an essential role in bone metabo- lism as well as in immunity. Hence, it might affect the devel- opment and extent of periodontal disease. The aim of this study was the assessment of 25-hydroxyvitamin D (25(OH)D) status in periodontal disease. Materials and methods Twenty-nine patients with severe periodontal disease and 29 healthy volunteers were recruited in this case-control-study. Serum 25(OH)D levels, Periodontal Probing Depth (PPD), Clinical Attachment Level (CAL), Bleeding on Probing (BOP), Body Mass Index (BMI), and current smoking status and smoking history (packyears) were assessed in all participants. Serum 25(OH)D levels were com- pared between controls and cases. Multivariable logistic regression was used to determine the odds ratio (OR) and 95 % confidence interval (CI) for periodontal disease in 25(OH)D deficient probands. Results Patients with periodontal disease presented a signifi- cantly higher proportion of deficient 25(OH)D levels (i.e., <50 nmol/l) compared to healthy controls (48 vs. 14 % respec- tively). The adjusted OR for periodontal disease with vitamin D deficiency was 1.5 (95 % CI, 1.13–1.98). No correlation between serum 25(OH)D levels and CAL, PPD, and BOP in the group with periodontal disease was found. Conclusions In this case-control-study 25(OH)D deficiency is significantly associated with periodontal disease. Clinical relevance The assessment of vitamin D levels in pa- tients presenting with periodontal disease seems advisable, as vitamin D deficiency might be involved in the onset and pro- gression of periodontal disease.
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| 5. |
- Lin, Xiaojing, et al.
(författare)
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Metal-enriched Neutral Gas Reservoir around a Strongly Lensed Low-mass Galaxy at z = 4 Identified by JWST/NIRISS and VLT/MUSE
- 2023
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Ingår i: Astrophysical Journal Letters. - : American Astronomical Society. - 2041-8213 .- 2041-8205. ; 944:2
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Tidskriftsartikel (refereegranskat)abstract
- Direct observations of low-mass, low-metallicity galaxies at z ≳ 4 provide an indispensable opportunity for detailed inspection of the ionization radiation, gas flow, and metal enrichment in sources similar to those that reionized the universe. Combining the James Webb Space Telescope (JWST), Very Large Telescope/MUSE, and Atacama Large Millimeter/submillimeter Array, we present detailed observations of a strongly lensed, low-mass (≈107.6 M ⊙) galaxy at z = 3.98 (also see Vanzella et al.). We identify strong narrow nebular emission, including C iv λ λ1548, 1550, He ii λ1640, O iii] λ λ1661, 1666, [Ne iii] λ3868, [O ii] λ3727, and the Balmer series of hydrogen from this galaxy, indicating a metal-poor H ii region (≲0.12 Z ⊙) powered by massive stars. Further, we detect a metal-enriched damped Lyα system (DLA) associated with the galaxy with the H i column density of N H I ≈ 1021.8 cm−2. The metallicity of the associated DLA may reach the supersolar metallicity (≳Z ⊙). Moreover, thanks to JWST and gravitational lensing, we present the resolved UV slope (β) map at the spatial resolution of ≈100 pc at z = 4, with steep UV slopes reaching β ≈ −2.5 around three star-forming clumps. Combining with low-redshift analogs, our observations suggest that low-mass, low-metallicity galaxies, which dominate reionization, could be surrounded by a high covering fraction of the metal-enriched, neutral-gaseous clouds. This implies that the metal enrichment of low-mass galaxies is highly efficient, and further supports that in low-mass galaxies, only a small fraction of ionizing radiation can escape through the interstellar or circumgalactic channels with low-column-density neutral gas.
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| 6. |
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The Seventeenth Data Release of the Sloan Digital Sky Surveys : Complete Release of MaNGA, MaStar, and APOGEE-2 Data
- 2022
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Ingår i: Astrophysical Journal Supplement Series. - : Institute of Physics (IOP). - 0067-0049 .- 1538-4365. ; 259:2
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Tidskriftsartikel (refereegranskat)abstract
- This paper documents the seventeenth data release (DR17) from the Sloan Digital Sky Surveys; the fifth and final release from the fourth phase (SDSS-IV). DR17 contains the complete release of the Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) survey, which reached its goal of surveying over 10,000 nearby galaxies. The complete release of the MaNGA Stellar Library accompanies this data, providing observations of almost 30,000 stars through the MaNGA instrument during bright time. DR17 also contains the complete release of the Apache Point Observatory Galactic Evolution Experiment 2 survey that publicly releases infrared spectra of over 650,000 stars. The main sample from the Extended Baryon Oscillation Spectroscopic Survey (eBOSS), as well as the subsurvey Time Domain Spectroscopic Survey data were fully released in DR16. New single-fiber optical spectroscopy released in DR17 is from the SPectroscipic IDentification of ERosita Survey subsurvey and the eBOSS-RM program. Along with the primary data sets, DR17 includes 25 new or updated value-added catalogs. This paper concludes the release of SDSS-IV survey data. SDSS continues into its fifth phase with observations already underway for the Milky Way Mapper, Local Volume Mapper, and Black Hole Mapper surveys.
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| 7. |
- Thompson, Rodger I., et al.
(författare)
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A molecular probe of dark energy
- 2008
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Ingår i: Advances in Space Research. - : Elsevier BV. - 1879-1948 .- 0273-1177. ; 42:3, s. 596-598
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Tidskriftsartikel (refereegranskat)abstract
- Many theoretical models of dark energy invoke rolling scaler fields which in turn predict time varying values of the fundamental constants. Establishing the value of the fundamental constants at various times in the universe can probe and test the various dark energy theories. One of the constants that is predicted to vary is the ratio of the electron to proton mass μ. It was established early on that molecular spectra are sensitive to the value of μ and can be used as probes of that value. This article describes the use of the spectrum of molecular hydrogen in high redshift Damped Lyman Alpha systems (DLAs) as a sensitive probe of the time evolution of μ.
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| 8. |
- Thompson, Rodger I., et al.
(författare)
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An observational determination of the proton to electron mass ratio in the early Universe
- 2009
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Ingår i: Astrophysical Journal. - 1538-4357 .- 0004-637X. ; 703:2009 October 1, s. 1648 - 1662
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Tidskriftsartikel (refereegranskat)abstract
- In an effort to resolve the discrepancy between two measurements of the fundamental constant μ, the proton to electron mass ratio, at early times in the universe we reanalyze the same data used in the earlier studies. Our analysis of the molecular hydrogen absorption lines in archival Very Large Telescope/Ultraviolet and Visible Echelle Spectrometer (UVES) spectra of the damped Lyman alpha systems in the quasi-stellar objects Q0347-383 and Q0405-443 yields a combined measurement of a Δμ/μ value of (–7 ± 8) × 10–6, consistent with no change in the value of μ over a time span of 11.5 Gyr. Here, we define Δμ as (μ z – μ0) where μ z is the value of μ at a redshift of z and μ0 is the present-day value. Our null result is consistent with the recent measurements of King et al., Δμ/μ = (2.6 ± 3.0) × 10–6, and inconsistent with the positive detection of a change in μ by Reinhold et al. Both of the previous studies and this study are based on the same data but with differing analysis methods. Improvements in the wavelength calibration over the UVES pipeline calibration is a key element in both of the null results. This leads to the conclusion that the fundamental constant μ is unchanged to an accuracy of 10–5 over the last 80% of the age of the universe, well into the matter dominated epoch. This limit provides constraints on models of dark energy that invoke rolling scalar fields and also limits the parameter space of supersymmetric or string theory models of physics. New instruments, both planned and under construction, will provide opportunities to greatly improve the accuracy of these measurements.
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| 9. |
- Wang, R., et al.
(författare)
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STAR FORMATION AND GAS KINEMATICS OF QUASAR HOST GALAXIES AT z similar to 6: NEW INSIGHTS FROM ALMA
- 2013
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Ingår i: Astrophysical Journal. - : American Astronomical Society. - 1538-4357 .- 0004-637X. ; 773:1
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Tidskriftsartikel (refereegranskat)abstract
- We present Atacama Large Millimeter/submillimeter Array (ALMA) observations of the [C Pi] 158 mu m fine structure line and dust continuum emission from the host galaxies of five redshift 6 quasars. We also report complementary observations of 250 GHz dust continuum and CO (6-5) line emission from the z = 6.00 quasar SDSS J231038.88+185519.7 using the IRAM facilities. The ALMA observations were carried out in the extended array at 0.'' 7 resolution. We have detected the line and dust continuum in all five objects. The derived [C Pi] line luminosities are 1.6 x 10(9) to 8.7 x 10(9) L-circle dot and the [C Pi]-to-FIR luminosity ratios are 2.9-5.1 x 10(-4), which is comparable to the values found in other high-redshift quasar-starburst systems and local ultra-luminous infrared galaxies. The sources are marginally resolved and the intrinsic source sizes (major axis FWHM) are constrained to be 0.'' 3-0.'' 6 (i.e., 1.7-3.5 kpc) for the [C Pi] line emission and 0.'' 2-0.'' 4 (i.e., 1.2-2.3 kpc) for the continuum. These measurements indicate that there is vigorous star formation over the central few kpc in the quasar host galaxies. The ALMA observations also constrain the dynamical properties of the star-forming gas in the nuclear region. The intensity-weighted velocity maps of three sources show clear velocity gradients. Such velocity gradients are consistent with a rotating, gravitationally bound gas component, although they are not uniquely interpreted as such. Under the simplifying assumption of rotation, the implied dynamical masses within the [C Pi]-emitting regions are of order 10(10)-10(11) M-circle dot. Given these estimates, the mass ratios between the supermassive black holes and the spheroidal bulge are an order of magnitude higher than the mean value found in local spheroidal galaxies, which is in agreement with results from previous CO observations of high redshift quasars.
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| 10. |
- Wehner, Christian, et al.
(författare)
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Characteristics and frequency distribution of bone defect configurations in peri-implantitis lesions : A series of 193 cases
- 2021
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Ingår i: Clinical Implant Dentistry and Related Research. - : John Wiley & Sons. - 1523-0899 .- 1708-8208. ; 23:2, s. 178-188
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Tidskriftsartikel (refereegranskat)abstract
- Background:Knowledge on peri‐implantitis bone defect characteristics and predictors is still limited.Purpose:To describe peri‐implantitis bone defect characteristics and identify possible predictors.Methods:Various parameters at patient‐ (age, gender, smoking, and supra‐structure), implant‐ (surface, type, connection, platform, and misfit), and site level (region, alveolar ridge position, defect characteristics, neighboring structure) were recorded retrospectively.Results:Among 193 implants, the most prevalent defects were class Ic (25.4%), and Id (23.8%); a previously non‐described category “class Id with only one bone wall” was frequently observed (11.9%). Mean intrabony defect depth and width ranged from 4.5 to 6.2 mm and from 2.7 to 2.9 mm, respectively; mean dehiscence extent ranged from 2.8 to 7.0 mm. A total of 37.8% of the defects presented horizontal bone loss and an intrabony component; in 52.7% of the implants, total defect extent was >6 mm. Jaw region, implant position within the alveolar ridge, and implant/abutment misfit showed significant associations either to defect configuration and/or defect extent.Conclusion:(a) Most common peri‐implantitis defects exhibited a combination of intrabony component and a buccal/oral dehiscence, while purely circumferential defects were relatively seldom; (b) implants with defects with bone dehiscence were placed more frequently closer to the lateral aspect of the ridge harboring the dehiscence; (c) implants placed in the lower anterior region had the highest risk for more severe peri‐implant bone loss; and (d) peri‐implant bone defects with only a single bone wall appropriate for regenerative procedure were relatively frequent.
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