scholarly journals Intracluster Planetary Nebulae

2003 ◽  
Vol 209 ◽  
pp. 597-604 ◽  
Author(s):  
John J. Feldmeier

We review the progress of research on intracluster planetary nebulae (IPN). In the past five years, hundreds of IPN candidates have been detected in the Virgo and Fornax galaxy clusters and searches are also underway in poorer galaxy groups. From the observations to date, and applying the known properties of extragalactic planetary nebulae, the intracluster light in Virgo and Fornax: 1) is significant, at least 20% of the total cluster stellar luminosity, 2) is elongated in Virgo along our line of sight, and 3) may derive from lower-luminosity galaxies, consistent with some models of intracluster star production. A fraction of IPN candidates are not true IPN, but emission-line sources of very large observed equivalent width (≥ 200 Å). The most likely source for these contaminating objects are Lyman-α galaxies at z ≈ 3.1. Follow-up spectroscopy of the IPN candidates will be crucial to discriminate against high red-shift galaxies and to derive the velocity field of the intracluster stellar population.

2015 ◽  
Vol 11 (S317) ◽  
pp. 69-76
Author(s):  
Magda Arnaboldi ◽  
Alessia Longobardi ◽  
Ortwin Gerhard

AbstractThe diffuse extended outer regions of galaxies are hard to study because they are faint, with typical surface brightness of 1% of the dark night sky. We can tackle this problem by using resolved star tracers which remain visible at large distances from the galaxy centers. This article describes the use of Planetary Nebulae as tracers and the calibration of their properties as indicators of the star formation history, mean age and metallicity of the parent stars in the Milky Way and Local Group galaxies. We then report on the results from a deep, extended, planetary nebulae survey in a 0.5 deg2region centered on the brightest cluster galaxy NGC 4486 (M87) in the Virgo cluster core, carried out with SuprimeCam@Subaru and FLAMES-GIRAFFE@VLT. Two planetary nebulae populations are identified out to 150 kpc distance from the center of M87. One population is associated with the M87 halo and the second one with the intracluster light in the Virgo cluster core. They have different line-of-sight velocity and spatial distributions, as well as different planetary nebulae specific frequencies and luminosity functions. The intracluster planetary nebulae in the surveyed region correspond to a luminosity of four times the luminosity of the Large Magellanic Cloud. The M87 halo planetary nebulae trace an older, more metal-rich, parent stellar population. A substructure detected in the projected phase-space of the line-of-sight velocity vs. major axis distance for the M87 halo planetary nebulae provides evidence for the recent accretion event of a satellite galaxy with luminosity twice that of M33. The satellite stars were tidally stripped about 1 Gyr ago, and reached apocenter at a major axis distance of 60–90 kpc from the center of M87. The M87 halo is still growing significantly at the distances where the substructure is detected.


1999 ◽  
Vol 191 ◽  
pp. 500-510 ◽  
Author(s):  
H. Dejonghe ◽  
K. Van Caelenberg

AGB stars, seen as a stellar population, can be used to probe the dynamical state of galaxies. The relevant data are mostly positions and line-of-sight velocities, sometimes together with information on chemical composition and/or age. As of now, dynamical models have been made for OH/IR stars and Planetary Nebulae. Other candidates are C stars, S stars, and Miras. We review the methods used and the results obtained so far, for the Milky Way and for (relatively nearby) extragalactic stellar systems.


2004 ◽  
Vol 217 ◽  
pp. 64-69 ◽  
Author(s):  
John J. Feldmeier ◽  
Robin B. Ciardullo ◽  
George H. Jacoby ◽  
Patrick R. Durrell ◽  
J. Christopher Mihos

We present the results from multiple surveys for intracluster planetary nebulae (IPNe) in nearby galaxy clusters and groups. We find that in the case of clusters, our observations imply: 1) the amount of intracluster starlight is significant, up to 20% of the total starlight, 2) in Virgo, is elongated along our line of sight, and 3) is clustered on the sky, implying ongoing tidal stripping. In contrast, searches for IPNe in groups have found little or no intra-group population, implying there may be something in the cluster environment that significantly enhances intracluster star production. from high-resolution N-body simulations, we find that the IPNe should create observable features in position-velocity space, and that these features may eventually allow us to place limits on the dynamics of galaxy clusters.


1993 ◽  
Vol 153 ◽  
pp. 437-438
Author(s):  
T. B. Williams ◽  
P. Saha

The observed spectrum of a galaxy is the composite spectrum of its stellar population broadened by the stellar velocities. Our topic is the extraction of the broadening functions (i.e., line-of-sight velocity distributions) from spectra. In the past, observers tried to extract only mean velocities and dispersions. But recent work on deconvolution [Franx & Illingworth ApJL327, L55 (1989), Bender A&A229, 441 (1990), Rix & White MNRAS254, 389 (1992), van der Marel & Franx ApJ, to appear] shows that more information can be recovered. The general idea is to compare a galaxy spectrum with one or more stellar ‘template’ spectra; but various methods differ widely in the treatment of noise and the control of sources of systematic error.


2021 ◽  
pp. 106689692098834
Author(s):  
Raquel Machado-Neves ◽  
Bernardo Teixeira ◽  
Elsa Fonseca ◽  
Pedro Valente ◽  
Joaquim Lindoro ◽  
...  

Most malignant tumors of the penis are squamous cell carcinomas (SCC), being divided in 2 groups, one human papillomavirus (HPV)-related and another non-HPV-related, with lymphoepithelioma-like carcinoma (LELC) being one of the rarest HPV-related SCC. In this article, we report a case of a 50-year-old man who presented testicular swelling and pain for the past 3 months. A penile mass was identified, and the patient was submitted to a total penectomy. The penectomy specimen showed an ulcerated lesion at the glans reaching the cavernous bodies. Microscopic examination showed undifferentiated epithelial cells with syncytial growth pattern mix with a dense lymphoplasmacytic infiltrate, consistent with LELC. The tumor cells expressed p16 and all 3 different clones of PDL1 (22C3, SP263, and SP142). The patient is alive and well with a follow-up of 3 months. To our knowledge, this is the third LELC of the penis reported in literature and the first case reported with PDL1 expression.


Rheumatology ◽  
2021 ◽  
Vol 60 (Supplement_1) ◽  
Author(s):  
Nadezhda Tsurikova ◽  
Elena Ligostaeva ◽  
Vadim Avdeenko ◽  
Nataliya Kobzeva ◽  
Irina Tsiganok ◽  
...  

Abstract Background/Aims  During the COVID-19 pandemic, analysis of the incidence of COVID-19 among patients suffering from rheumatic diseases and receiving therapy with biological agents remains relevant. Methods  This single-center observational study included 118 children suffering from various rheumatic diseases and receiving therapy with anti-rheumatic drugs and biological agents. In this research, we analyzed the incidence of CIVID-19 and the frequency of documented contact with SARS-CoV-2 in the period from 01.03.2020 to 11.10.2020 (32 weeks). The results were analyzed using descriptive statistics. Results  Among 118 children, there were 28 (24%) boys and 90 (76%) girls, average age 10.3±4.2. 104 (88.2%) patients had different types of juvenile idiopathic arthritis (JIA), 2 (1.6%) children had systemic lupus erythematosus (SLE), 2 (1.6%) patients had juvenile dermatomyositis (JDM), 1 (1%) child had ANCA-associated vasculitis, 6 (5%) patients had familial Mediterranean fever (FMF), 2 (1.6%) children had deficiency of adenosine deaminase 2 (DADA2), 1 (1%) child had TNF receptor-associated periodic syndrome (TRAPS). In this group of patients 94 (79%) patients were treated with methotrexate, 1 (1%) - azathioprine, 3 (2%) patients received hydroxychloroquine, 6(5%) - mycophenolate mofetil, 4 (3%) - sulfasalazine, 14(11%) children received prednisone, 6(5%) - cyclosporine A. All children included in this study received biological agents for more than 1 year, the distribution of biological agents among patients was as follows: 41(34%) - etanercept, 33(28%) - adalimumab, 24 (20%) - tocilizumab, 7 (6%) - canakinumab, 3 (2%) - abatacept, 4 (3%) - golimumab, 6 (5%) - rituximab. Out of 118 children, 4 (3%) patients had flu-like symptoms and positive results of PCR tests for COVID-19 (1 patient was treated with etanercept, 1 - adalimumab, 1 - tocilizumab, 1 - rituximab), none of the patients had signs of SARS-CoV-2 pneumonia. 10 (8%) patients had documented contact with COVID-19: among this patients 2 children had flu-like symptoms, positive results of PCR tests and absence of COVID-19 pneumonia (one of this patient was treated with adalimumab, another one - with rituximab), one more patient was treated with tocilizumab and had positive PCR test without any symptoms of COVID-19; other 7 children had negative PCR tests and didn’t have any signs of COVID-19. Conclusion  Among our patients with various rheumatic diseases treated with biological agents there were no registered severe cases of COVID-19. Over the past period (32 weeks of follow-up) 3% of children with COVID-19 were identified and 8% patients had documented contact with COVID-19, but we suppose it is too early to make conclusions about the degree and severity of COVID-19 among children suffering from rheumatic diseases and receiving various biological agents. Further follow-up is needed to better understand the risk and impact of COVID-19 among children with rheumatic diseases and receiving therapy with biological agents. Disclosure  N. Tsurikova: None. E. Ligostaeva: None. V. Avdeenko: None. N. Kobzeva: None. I. Tsiganok: None. K. Skorobogatova: None. A. Motkina: None.


2020 ◽  
Vol 7 (Supplement_1) ◽  
pp. S441-S442
Author(s):  
Xing Tan ◽  
Andrew M Skinner ◽  
Benjamin Sirbu ◽  
Larry H Danziger ◽  
Dale N Gerding ◽  
...  

Abstract Background There is a paucity of data assessing outcomes of alternate fidaxomicin strategies in patients with recurrent Clostridioides difficile infection (rCDI). The objective of our study is to evaluate a tapered-pulsed (T-P) fidaxomicin regimen that was administered immediately following a course of CDI treatment with initial symptom resolution in patients with multiple rCDI. Methods We reviewed the characteristics and outcomes of 46 consecutive patients who received T-P fidaxomicin between January 1, 2014-June 30, 2019 in a specialty CDI clinic. The first episode in which fidaxomicin T-P was administered was analyzed. Failure was defined as the persistence of diarrhea and/or the need for additional CDI treatment at any time on T-P fidaxomicin. Sustained clinical cure (SCC) was defined as resolution of diarrhea without recurrence. Recurrence was defined as the return of diarrhea requiring retreatment with CDI therapy after completion of T-P fidaxomicin. Both SCC and recurrence were evaluated at 30 and 90 days after completion of T-P fidaxomicin. Results The mean±SD age of the 46 patients was 63.2±19.9 years, 71.7% were female, and the mean±SD CDI episodes within the past year was 3±1.4 . Most patients (73.9%) had previously failed a vancomycin tapered and/or pulsed regimen. Prior to administering T-P fidaxomicin, a treatment regimen was given to ensure resolution of symptoms. The CDI treatment most commonly used (58.7%) was vancomycin. The T-P fidaxomicin regimen used consisted of 200 mg given once daily for 7 days followed by 200 mg every other day for a median (min-max) duration of 33 (6-120) days. Two patients (4%) failed to respond to T-P fidaxomicin; 34 (74%) and 28 (61%) achieved SCC at 30 and 90 days, respectively. Among the 44 patients that successfully completed the T-P fidaxomicin regimen, recurrence developed in 10 (22.7%) and 16 (36.4%) of patients at 30 and 90 days, respectively, with a median (min-max) time to recurrence of 20 (3-87) days (Figure 1). Four patients with recurrence had received subsequent systemic antibiotics. Figure 1. Course of CDI therapy and follow-up Conclusion A tapered-pulsed fidaxomicin strategy may be effective in patients with multiply rCDI who are refractory to other treatments, including a vancomycin tapered and pulsed regimen. Disclosures Larry H. Danziger, PharmD, Merck (Speaker’s Bureau)


2021 ◽  
pp. 1-11
Author(s):  
Chang Liu ◽  
Murat Yücel ◽  
Chao Suo ◽  
Mike E. Le Pelley ◽  
Jeggan Tiego ◽  
...  

Background: To date, there has been little investigation on how motivational and cognitive mechanisms interact to influence problematic drinking behaviours. Towards this aim, the current study examined whether reward-related attentional capture is associated with reward, fear (relief), and habit drinking motives, and further, whether it interacts with these motives in relation to problematic drinking patterns. Methods: Ninety participants (mean age = 34.8 years, SD = 9.1, 54% male) who reported having consumed alcohol in the past month completed an online visual search task that measured reward-related attentional capture as well as the Habit Reward Fear Scale, a measure of drinking motives. Participants also completed measures of psychological distress, impulsivity, compulsive drinking, and consumption items of Alcohol Use Disorders Identification Test. Regression analyses examined the associations between motives for alcohol consumption and reward-related attentional capture, as well as the associations between reward-related attentional capture, motives, and their interaction, with alcohol consumption and problems. Results: Greater reward-related attentional capture was associated with greater reward motives. Further, reward-related attentional capture also interacted with fear motives in relation to alcohol consumption. Follow-up analyses showed that this interaction was driven by greater fear motives being associated with heavier drinking among those with lower reward-related attentional capture (i.e., “goal-trackers”). Conclusion: These findings have implications for understanding how cognition may interact with motives in association with problematic drinking. Specifically, the findings highlight different potential pathways to problematic drinking according to an individual’s cognitive-motivational profile and may inform tailored interventions to target profile-specific mechanisms. Finally, these findings offer support for contemporary models of addiction that view excessive goal-directed behaviour under negative affect as a critical contributor to addictive behaviours.


1991 ◽  
Vol 148 ◽  
pp. 15-23 ◽  
Author(s):  
B. E. Westerlund

A vast amount of observational data concerning the structure and kinematics of the Magellanic Clouds is now available. Many basic quantities (e.g. distances and geometry) are, however, not yet sufficiently well determined. Interactions between the Small Magellanic Cloud (SMC), the Large Magellanic Cloud (LMC) and our Galaxy have dominated the evolution of the Clouds, causing bursts of star formation which, together with stochastic self-propagating star formation, produced the observed structures. In the youngest generation in the LMC it is seen as an intricate pattern imitating a fragmented spiral structure. In the SMC much of the fragmentation is along the line of sight complicating the reconstruction of its history. The violent events in the past are also recognizable in complex velocity patterns which make the analysis of the kinematics of the Clouds difficult.


2015 ◽  
Vol 2015 ◽  
pp. 1-4 ◽  
Author(s):  
Amresh Kumar Singh ◽  
Rungmei S. K. Marak ◽  
Anand Kumar Maurya ◽  
Manaswini Das ◽  
Vijaya Lakshmi Nag ◽  
...  

Nontuberculous mycobacteria (NTMs) are ubiquitous and are being increasingly reported as human opportunistic infection. Cutaneous infection caused by mixed NTM is extremely rare. We encountered the case of a 46-year-old female, who presented with multiple discharging sinuses over the lower anterior abdominal wall (over a previous appendectomy scar) for the past 2 years. Microscopy and culture of the pus discharge were done to isolate and identify the etiological agent. Finally, GenoType Mycobacterium CM/AS assay proved it to be a mixed infection caused byMycobacterium szulgaiandM. intermedium. The patient was advised a combination of rifampicin 600 mg once daily, ethambutol 600 mg once daily, and clarithromycin 500 mg twice daily to be taken along with periodic follow-up based upon clinical response as well as microbiological response. We emphasize that infections by NTM must be considered in the etiology of nonhealing wounds or sinuses, especially at postsurgical sites.


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