scholarly journals The SkyMapper DR1.1 search for extremely metal-poor stars

2019 ◽  
Vol 489 (4) ◽  
pp. 5900-5918 ◽  
Author(s):  
G S Da Costa ◽  
M S Bessell ◽  
A D Mackey ◽  
T Nordlander ◽  
M Asplund ◽  
...  

ABSTRACT We present and discuss the results of a search for extremely metal-poor stars based on photometry from data release DR1.1 of the SkyMapper imaging survey of the southern sky. In particular, we outline our photometric selection procedures and describe the low-resolution (R ≈ 3000) spectroscopic follow-up observations that are used to provide estimates of effective temperature, surface gravity, and metallicity ([Fe/H]) for the candidates. The selection process is very efficient: of the 2618 candidates with low-resolution spectra that have photometric metallicity estimates less than or equal to −2.0, 41 per cent have [Fe/H] ≤ −2.75 and only approximately seven per cent have [Fe/H] > −2.0 dex. The most metal-poor candidate in the sample has [Fe/H] < −4.75 and is notably carbon rich. Except at the lowest metallicities ([Fe/H] < −4), the stars observed spectroscopically are dominated by a ‘carbon-normal’ population with [C/Fe]1D, LTE ≤ +1 dex. Consideration of the A(C)1D, LTE versus [Fe/H]1D, LTE diagram suggests that the current selection process is strongly biased against stars with A(C)1D, LTE > 7.3 (predominantly CEMP-s) while any bias against stars with A(C)1D, LTE < 7.3 and [C/Fe]1D,LTE > +1 (predominantly CEMP-no) is not readily quantifiable given the uncertainty in the SkyMapper v-band DR1.1 photometry. We find that the metallicity distribution function of the observed sample has a power-law slope of Δ(Log N)/Δ[Fe/H] = 1.5 ± 0.1 dex per dex for −4.0 ≤ [Fe/H] ≤ −2.75, but appears to drop abruptly at [Fe/H] ≈ −4.2, in line with previous studies.

1971 ◽  
Vol 13 (2) ◽  
pp. 209-218 ◽  
Author(s):  
C. J. M. Hinks

SUMMARYA numerical model of male and female replacement processes in a dairy cattle population was constructed in order to describe the long-term genetic and financial consequences of selection amongst bulls in AI.Changes with time in the relative contribution of different generations of offspring to the total genetic improvement of the population were described. It was shown that the genetic change resulting from a single selection process amongst the males eventually approaches an equilibrium many years after selection is practised. Owing to the delays involved in the progeny test, individual males made no genetic contribution for a period of 10 years and a small but constant contribution thereafter.The costs of bull testing and selection, and the monetary benefits obtained from it, were estimated. Current selection procedures proved to be highly profitable at prevailing market prices. Capital invested in the testing programme was recovered within 2 to 5 years of the first offspring calving.The effect of changes in milk prices and feeding costs on monetary returns was examined. It was concluded that sire testing programmes are likely to prove unprofitable only under extremely adverse economic conditions.


2019 ◽  
Vol 626 ◽  
pp. A16 ◽  
Author(s):  
A. Rojas-Arriagada ◽  
M. Zoccali ◽  
M. Schultheis ◽  
A. Recio-Blanco ◽  
G. Zasowski ◽  
...  

Context. The Galactic bulge has a bimodal metallicity distribution function: different kinematic, spatial, and, potentially, age distributions characterize the metal-poor and metal-rich components. Despite this observed dichotomy, which argues for different formation channels for those stars, the distribution of bulge stars in the α-abundance versus metallicity plane has been found so far to be a rather smooth single sequence. Aims. We use data from the fourteenth data release of the APOGEE spectroscopic survey (DR14) to investigate the distribution in the Mg abundance (as tracer of the α-elements)-versus-metallicity plane of a sample of stars selected to be in the inner region of the bulge. Methods. A clean sample has been selected from the DR14 using a set of data- and pipeline-flags to ensure the quality of their fundamental parameters and elemental abundances. An additional selection made use of computed spectro-photometric distances to select a sample of likely bulge stars as those with RGC ≤ 3.5 kpc. We adopt magnesium abundance as an α-abundance proxy for our clean sample as it has been proven to be the most accurate α-element as determined by ASPCAP, the pipeline for data products from APOGEE spectra. Results. From the distribution of our bulge sample in the [Mg/Fe]-versus-[Fe/H] plane, we found that the sequence is bimodal. This bimodality is given by the presence of a low-Mg sequence of stars parallel to the main high-Mg sequence over a range of ∼0.5 dex around solar metallicity. The two sequences merge above [Fe/H] ∼ 0.15 dex into a single sequence whose dispersion in [Mg/Fe] is larger than either of the two sequences visible at lower metallicity. This result is confirmed when we consider stars in our sample that are inside the bulge region according to trustworthy Gaia DR2 distances.


RMD Open ◽  
2021 ◽  
Vol 7 (3) ◽  
pp. e001906
Author(s):  
Marlou THF Janssen ◽  
Sofia Ramiro ◽  
Rémy LM Mostard ◽  
Cesar Magro-Checa ◽  
Robert BM Landewé

ObjectivesTo prospectively investigate differences in medium-term patient-reported outcome measures and objective functional outcome measures, between patients receiving and those not receiving intensive short-term immunosuppressive therapy for coronavirus disease 19 (COVID-19)-associated hyperinflammation.MethodsPatients previously included in the COVID-19 High-intensity Immunosuppression in Cytokine storm syndrome (CHIC) study who received immunosuppressive treatment versus standard of care for COVID-19-associated hyperinflammation were invited for follow-up at 3 and 6 months after hospitalisation. At both visits, patients were assessed by a pulmonologist, completed quality of life (QoL) questionnaires and performed pulmonary and exercise function tests. At 3 months, patients additionally completed questionnaires on dyspnoea, anxiety, depression and trauma. Outcomes were compared between patients receiving and those not receiving intensive short-term immunosuppressive therapy for COVID-19-associated hyperinflammation.Results131 (66.5%) patients survived hospitalisation due to COVID-19-associated hyperinflammation and 118 (90.1%) were included. QoL questionnaires, pulmonary- and exercise function tests showed improvement between 3 and 6 months after discharge, which was similar in both groups. Assessed patients reached levels that were close to levels predicted from the normal population. In contrast, diffusing capacity of the lung for carbon monoxide was disturbed in both groups: 69.6% predicted (SD 16.2) and 73.5% predicted (SD 16.5) in control group and treated group, respectively.ConclusionsNo differences in medium-term outcomes are demonstrated in survivors of COVID-19-associated hyperinflammation treated or not treated with methylprednisolone with or without tocilizumab during the acute phase. Short-term benefits of this therapy, as showed in the baseline CHIC study analysis, are thus not hampered by medium-term adverse events.


Author(s):  
Zheng Wang ◽  
Zhixiang Wang ◽  
Yinqiang Zheng ◽  
Yang Wu ◽  
Wenjun Zeng ◽  
...  

An efficient and effective person re-identification (ReID) system relieves the users from painful and boring video watching and accelerates the process of video analysis. Recently, with the explosive demands of practical applications, a lot of research efforts have been dedicated to heterogeneous person re-identification (Hetero-ReID). In this paper, we provide a comprehensive review of state-of-the-art Hetero-ReID methods that address the challenge of inter-modality discrepancies. According to the application scenario, we classify the methods into four categories --- low-resolution, infrared, sketch, and text. We begin with an introduction of ReID, and make a comparison between Homogeneous ReID (Homo-ReID) and Hetero-ReID tasks. Then, we describe and compare existing datasets for performing evaluations, and survey the models that have been widely employed in Hetero-ReID. We also summarize and compare the representative approaches from two perspectives, i.e., the application scenario and the learning pipeline. We conclude by a discussion of some future research directions. Follow-up updates are available at https://github.com/lightChaserX/Awesome-Hetero-reID


2021 ◽  
Vol 21 (10) ◽  
pp. 249
Author(s):  
Zhong-Rui Bai ◽  
Hao-Tong Zhang ◽  
Hai-Long Yuan ◽  
Dong-Wei Fan ◽  
Bo-Liang He ◽  
...  

Abstract LAMOST Data Release 5, covering ∼17 000 deg2 from –10° to 80° in declination, contains 9 million co-added low-resolution spectra of celestial objects, each spectrum combined from repeat exposure of two to tens of times during Oct 2011 to Jun 2017. In this paper, we present the spectra of individual exposures for all the objects in LAMOST Data Release 5. For each spectrum, the equivalent width of 60 lines from 11 different elements are calculated with a new method combining the actual line core and fitted line wings. For stars earlier than F type, the Balmer lines are fitted with both emission and absorption profiles once two components are detected. Radial velocity of each individual exposure is measured by minimizing χ 2 between the spectrum and its best template. The database for equivalent widths of spectral lines and radial velocities of individual spectra are available online. Radial velocity uncertainties with different stellar type and signal-to-noise ratio are quantified by comparing different exposure of the same objects. We notice that the radial velocity uncertainty depends on the time lag between observations. For stars observed in the same day and with signal-to-noise ratio higher than 20, the radial velocity uncertainty is below 5km s−1, and increases to 10 km s−1 for stars observed in different nights.


2014 ◽  
Vol 29 (4) ◽  
pp. 259-263 ◽  
Author(s):  
S. Dalsgaard ◽  
P.B. Mortensen ◽  
M. Frydenberg ◽  
C.M. Maibing ◽  
M. Nordentoft ◽  
...  

AbstractPurpose:To estimate the risk of schizophrenia in adulthood among children and adolescents with ADHD compared to the background population.Subjects/materials and methods:Two hundred and eight youths with ADHD (183 boys; 25 girls) were followed prospectively. Diagnoses of schizophrenia were obtained from The Danish Psychiatric Central Register. The relative risk (RR) of schizophrenia for cases with ADHD, compared to the normal population, was calculated as risk ratios. Hazard ratios (HR's) by Cox regression were calculated in the predictor analyses.Results:Mean age for ADHD cases at follow-up was 31.1 years. Schizophrenia diagnoses were given to 3.8% of these cases. Compared to the general population, RR of schizophrenia in cases with ADHD was 4.3 (95% CI 1.9–8.57).Discussion and conclusion:This prospective follow-up study found children with ADHD to be at higher risk of later schizophrenia than controls. If replicated, these results warrant increased focus on the possible emergence symptoms of schizophrenia or schizophreniform psychosis during clinical follow-up of patients with ADHD.


1970 ◽  
Vol 64 (10) ◽  
pp. 325-329
Author(s):  
Ronald G. Rice ◽  
John E. Muthard ◽  
Neil S. Dumas

□ At the present time, there does not seem to be sufficient need to justify the expense of validating a selection battery on a national scale. The results of the questionnaire indicated a current rate of success in rehabilitating VSO's which could not be improved appreciably by a selection battery. The present report provides a current look at the evaluation, selection, training, and follow-up success experienced by state agencies. The feasibility of continuing study of the VSO and the review of possible selection procedures have also been reviewed.


2010 ◽  
Vol 30 (S 01) ◽  
pp. S104-S106
Author(s):  
W. Miesbach ◽  
L. M. Sahner ◽  
A. Kurth ◽  
B. Habermann

Summary Purpose Purpose of this retrospective study was to evaluate our own results after total knee replacement in patients with haemophilia. Patients, material, method: 30 patients with haemophilia who underwent total knee replacement between 1987 and 2005 were included. We used the clinical and radiological Knee Society Score. Furthermore, the Petterson and the Arnold and Hilgartner score were applied. Results: The mean age at the time of surgery was 43.2 (27–66). At the time of follow- up examination the mean age was 51.6 (30–82) years. The mean follow-up was 7.1 (2–20) years. Preoperative, he mean Arnold and Hilgartner score was 4.17 (± 0.59) and the mean Petterson-Score was 9 ± 2.29. Compared to the preoperative deficiency in knee function (KSS-Score 88.17 ± 33.58) an improvement with 166.67 (± 22.73) points was seen. 1 patient showed an aseptic loosening after 11 years. Discussion: Total knee replacement in patients with haemophilia improves knee function and quality of life. The results of our study represent results in earlier published studies. Compared to a non-haemo-philic normal population the rate of perioper-ative complications was not increased.


2020 ◽  
Vol 9 (8) ◽  
pp. 2498 ◽  
Author(s):  
Pol Maria Rommens ◽  
Johannes Christof Hopf ◽  
Michiel Herteleer ◽  
Benjamin Devlieger ◽  
Alexander Hofmann ◽  
...  

Background: Fractures of the pubic ramus without involvement of the posterior pelvic ring represent a minority of fragility fractures of the pelvis (FFP). The natural history of patients suffering this FFP Type I has not been described so far. Material and methods: All patients, who were admitted with isolated pubic ramus fractures between 2007 and mid-2018, have been reviewed. Epidemiologic data, comorbidities, in-hospital complications, and one-year mortality were recorded. Of all surviving patients, living condition before the fracture and at follow-up was noted. Mobility was scored with the Parker Mobility Score, quality of life with the European Quality of Life 5 Dimensions 3 Level (EQ-5D-3L), subjective sensation of pain with the Numeric Rating Scale (NRS). Results: A consecutive series of 138 patients was included in the study. There were 117 women (84.8%) and 21 men (15.2%). Mean age was 80.6 years (SD 8.6 years). 89.1% of patients presented with comorbidities, 81.2% of them had cardiovascular diseases. Five patients (4%) died during hospital-stay. Median in-hospital stay was eight days (2–45 days). There were in-hospital complications in 16.5%, urinary tract infections, and pneumonia being the most frequent. One-year mortality was 16.7%. Reference values for the normal population of the same age are 5.9% for men and 4.0% for women. One-year mortality rate was 22.2% in the patient group of 80 years or above and 8.8% in the patient group below the age of 80. The rate of surviving patients living at home with or without assistance dropped from 80.5% to 65.3%. The median EQ-5D-Index Value was 0.62 (0.04–1; IQR 0.5–0.78). Reference value for the normal population is 0.78. Average PMS was 4 and NRS 3. Within a two-year period, additional fragility fractures occurred in 21.2% and antiresorptive medication was taken by only 45.2% of patients. Conclusion. Pubic ramus fractures without involvement of the posterior pelvis (FFP Type I) are serious adverse events for elderly persons. During follow-up, there is an excess mortality, a loss of independence, a restricted mobility, and a decreased quality of life. Pubic ramus fractures are indicators for the need to optimize the patient’s general condition.


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