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We present ALMA observations of the CO(1--0) and CO(3--2) line emission tracing filaments of cold molecular gas in the central galaxy of the cluster PKS 0745--191. The total molecular gas mass of 4.6 ± 0.3 × 109 M⊙, assuming a Galactic XCO factor, is divided roughly equally between three filaments each extending radially 3-5 kpc from the galaxy centre. The emission peak is located in the SE filament ~ 1 arcsec (2 kpc) from the nucleus. The velocities of the molecular clouds in the filaments are low, lying within ± 100 km s-1 of the galaxy's systemic velocity. Their full width at half-maximum (FWHM) are less than 150 km s-1, which is significantly below the stellar velocity dispersion. Although the molecular mass of each filament is comparable to a rich spiral galaxy, such low velocities show that the filaments are transient and the clouds would disperse on < 107 yr time-scales unless supported, likely by the indirect effect of magnetic fields. The velocity structure is inconsistent with a merger origin or gravitational free-fall of cooling gas in this massive central galaxy. If the molecular clouds originated in gas cooling even a few kpc from their current locations their velocities would exceed those observed. Instead, the projection of the N and SE filaments underneath X-ray cavities suggests they formed in the updraft behind bubbles buoyantly rising through the cluster atmosphere. Direct uplift of the dense gas by the radio bubbles appears to require an implausibly high coupling efficiency. The filaments are coincident with low temperature X-ray gas, bright optical line emission and dust lanes indicating that the molecular gas could have formed from lifted warmer gas that cooled in situ. [ABSTRACT FROM AUTHOR]

We report ALMA Early Science observations of the A1835 brightest cluster galaxy (BCG) in the CO (3-2) and CO (1-0) emission lines. We detect 5 × 1010M☼ of molecular gas within 10 kpc of the BCG. Its ensemble velocity profile width of ∼130 km s–1 FWHM is too narrow for the molecular clouds to be supported in the galaxy by dynamic pressure. The gas may instead be supported in a rotating, turbulent disk oriented nearly face-on. Roughly 1010M☼ of molecular gas is projected 3-10 kpc to the northwest and to the east of the nucleus with line-of-sight velocities lying between –250 km s–1 and +480 km s–1 with respect to the systemic velocity. The high-velocity gas may be either inflowing or outflowing. However, the absence of high-velocity gas toward the nucleus that would be expected in a steady inflow, and its bipolar distribution on either side of the nucleus, are more naturally explained as outflow. Star formation and radiation from the active galactic nucleus (AGN) are both incapable of driving an outflow of this magnitude. The location of the high-velocity gas projected behind buoyantly rising X-ray cavities and favorable energetics suggest an outflow driven by the radio AGN. If so, the molecular outflow may be associated with a hot outflow on larger scales reported by Kirkpatrick and colleagues. The molecular gas flow rate of approximately 200 M☼ yr–1 is comparable to the star formation rate of 100-180 M☼ yr–1 in the central disk. How radio bubbles would lift dense molecular gas in their updrafts, how much gas will be lost to the BCG, and how much will return to fuel future star formation and AGN activity are poorly understood. Our results imply that radio-mechanical (radio-mode) feedback not only heats hot atmospheres surrounding elliptical galaxies and BCGs, but it is able to sweep higher density molecular gas away from their centers. [ABSTRACT FROM AUTHOR]

Perinephric abscess caused by spread of infection from an adjacent extrarenal focus is rare. Prior to diagnosis, several features of this case suggested such a pathogenesis: absence of an associated upper urinary tract infection or a distant focus for hematogenous seeding, and late recurrence of the abscess despite prompt clinical response following drainage and antimicrobial therapy. Specifically, the large bowel was suspected early on and subsequently documented as the source of infection because of the unusual finding of a polymicrobial perinephric abscess.