12 research outputs found
A hot X-ray filament associated with A3017 galaxy cluster
Recent simulations and observations have shown large scale filaments in the
cosmic web connecting nodes, with accreting materials (baryonic and dark
matter) flowing through them. Current high sensitivity observations also show
that the propagation of shocks through filaments can heat them up, and make
filaments visible between two or more galaxy clusters or around massive
clusters, based on optical and/or X-ray observations. We are reporting here the
special case of the cluster A3017 associated with a hot filament. The
temperature of the filament is 3.4 ~keV and its length is
1 Mpc. We have analysed its archival {\it Chandra} data and report
various properties. We also analysed GMRT 235/610 MHz radio data. Radio
observations have revealed symmetric two-sided lobes which fill cavities in the
A3017 cluster core region, associated with central AGN. In the radio map, we
also noticed a peculiar linear vertical radio structure in the X-ray filament
region which might be associated with a cosmic filament shock. This radio
structure could be a radio phoenix or old plasma where an old relativistic
population is re-accelerated by shock propagation. Finally we put an upper
limit on the radio luminosity of the filament region
Daclatasvir-Sofosbuvir for treatment of hepatitis C virus in patients with inherited bleeding disorders
MACS J0553.4−3342: a young merging galaxy cluster caught through the eyes of Chandra and HST
We present a detailed analysis of a young merging galaxy cluster
\mac~(z=0.43), from {\it Chandra} X-ray and {\it Hubble Space Telescope}
archival data. X-ray observations confirm that the X-ray emitting intra-cluster
medium (ICM) in this system is among the hottest (average keV)
and most luminous known. Comparison of X-ray and optical images confirm that
this system hosts two merging subclusters SC1 and SC2, separated by a projected
distance of about 650\,kpc. The subcluster SC2 is newly identified in this
work, while another subcluster (SC0), previously thought to be part of this
merging system, is shown to be possibly a foreground object. Apart from two
subclusters, we find a tail-like structure in the X-ray image, extending to a
projected distance of 1\,Mpc, along the north-east direction of the
eastern subcluster (SC1). From a surface brightness analysis, we detect two
sharp surface brightness edges at 40\arcsec (320\,kpc) and
80\arcsec (640\,kpc) to the east of SC1. The inner edge appears
to be associated with a merger-driven cold front, while the outer one is likely
to be due to a shock front, the presence of which, ahead of the cold front,
makes this dynamically disturbed cluster interesting. Nearly all the early-type
galaxies belonging to the two subclusters, including their BCGs, are part of a
well-defined red sequence.Comment: 13 pages, 12 figures, 6 Tables, Accepted for publication in Monthly
Notices of the Royal Astronomical Society Main Journa
The rationale and design of Insight into Nephrotic Syndrome: Investigating Genes, Health and Therapeutics (INSIGHT): a prospective cohort study of childhood nephrotic syndrome
Abstract
Background
Nephrotic syndrome is one of the most commonly diagnosed kidney diseases in childhood and its progressive forms can lead to chronic kidney disease (CKD) and/or end-stage renal disease (ESRD). There have been few longitudinal studies among a multi-ethnic cohort to determine potential risk factors influencing disease susceptibility, treatment response, and progression of nephrotic syndrome. Temporal relationships cannot be studied through cross-sectional study design. Understanding the interaction between various factors is critical to developing new strategies for treating children with kidney disease. We present the rationale and the study design of a longitudinal cohort study of children with nephrotic syndrome, the Insight into Nephrotic Syndrome: Investigating Genes, Health and Therapeutics (INSIGHT) study. The specific aims are to determine: 1) socio-demographic, environmental, and genetic factors that influence disease susceptibility; 2) rates of steroid treatment resistance and steroid treatment dependence, and identify factors that may modify treatment response; 3) clinical and genetic factors that influence disease susceptibility and progression to CKD and ESRD; and 4) the interaction between the course of illness and socio-demographic, environmental, and clinical risk factors.
Methods/design
INSIGHT is a disease-based observational longitudinal cohort study of children with nephrotic syndrome. At baseline, participants complete questionnaires and provide biological specimen samples (blood, urine, and toenail clippings). Follow-up questionnaires and repeat biological specimen collections are performed annually for up to five years.
Discussion
The proposed cohort will provide the structure to test various risk factors predicting or influencing disease susceptibility, treatment response, and progression to CKD among children with nephrotic syndrome.
Trial registration
ClinicalTrials.gov Identifier NCT01605266