Multi-scale feedback and feeding in the closest radio galaxy Centaurus A

Supermassive black holes and supernova explosions at the centres of active galaxies power cycles of outflowing and inflowing gas that affect galactic evolution and the overall structure of the Universe(1,2). While simulations and observations show that this must be the case, the range of physical scales (over ten orders of magnitude) and paucity of available tracers make both the simulation and observation of these effects difficult(3,4). By serendipity, there lies an active galaxy, Centaurus A (NGC 5128)(5,6), at such a close proximity as to allow its observation over this entire range of scales and across the entire electromagnetic spectrum. In the radio band, however, details on scales of 10-100 kpc from the supermassive black hole have so far been obscured by instrumental limitations(7,8). Here we report low-frequency radio observations that overcome these limitations and show evidence for a broad, bipolar outflow with velocity of 1,100 km s(-1) and mass-outflow rate of 2.9 M-circle dot yr(-1) on these scales. We combine our data with the plethora of multiscale, multi-wavelength, historical observations of Centaurus A to probe a unified view of feeding and feedback, which we show to be consistent with the chaotic cold accretion self-regulation scenario(9,10)

A Stewardship Cost Perspective on the Governance of Delegation Relationships:The Case of Social Franchising

We explore how nonprofits can effectively govern delegation relationships. We extend stewardship theory by conceptualizing stewardship costs—costs in delegation relationships based on stewardship behavior. As stewards are theorized as other-regarding, self-actualizing, and intrinsically motivated, so far, literature almost exclusively points to the positive performance potential of stewardship behavior. Addressing this shortcoming, we develop propositions showing how stewardship selection costs rooted in the psychological characteristics of stewardship behavior and stewardship management costs rooted in situational factors of stewardship behavior occur during relationship formation and maintenance, and how they counteract the potential to increase performance. We identify and systematize opportunity costs of delayed growth, limited growth potential, and lost standardization gains, as well as increased selection and management costs. To demonstrate the theoretical potential and empirical relevance of our framework, we illustrate our arguments by referring to social franchising, a scaling strategy considered relevant for nonprofits as well as social enterprises

A randomized, comparative pilot trial of family-based interpersonal psychotherapy for reducing psychosocial symptoms, disordered-eating, and excess weight gain in at-risk preadolescents with loss-of-control-eating: SHOMAKER et al.

Preadolescent loss-of-control-eating (LOC-eating) is a risk factor for excess weight gain and binge-eating-disorder. We evaluated feasibility and acceptability of a preventive family-based interpersonal psychotherapy (FB-IPT) program. FB-IPT was compared to family-based health education (FB-HE) to evaluate changes in children’s psychosocial functioning, LOC-eating, and body mass

Cardiovascular magnetic resonance of pulmonary artery growth and ventricular function after Norwood procedure with Sano modification

For hypoplastic left heart syndrome (HLHS), there have been concerns regarding pulmonary artery growth and ventricular dysfunction after first stage surgery consisting of the Norwood procedure modified with a right ventricle-to-pulmonary artery conduit. We report our experience using cardiovascular magnetic resonance (CMR) to determine and follow pulmonary arterial growth and ventricular function in this cohort

Multi-scale feedback and feeding in the closest radio galaxy Centaurus A

Supermassive black holes and supernova explosions at the centres of active galaxies power cycles of outflowing and inflowing gas that affect galactic evolution and the overall structure of the Universe. While simulations and observations show that this must be the case, the range of physical scales (over ten orders of magnitude) and paucity of available tracers make both the simulation and observation of these effects difficult. By serendipity, there lies an active galaxy, Centaurus A (NGC 5128), at such a close proximity as to allow its observation over this entire range of scales and across the entire electromagnetic spectrum. In the radio band, however, details on scales of 10-100 kpc from the supermassive black hole have so far been obscured by instrumental limitations. Here we report low-frequency radio observations that overcome these limitations and show evidence for a broad, bipolar outflow with velocity of 1,100 km/s and mass-outflow rate of 2.9 M⊙/yr on these scales. We combine our data with the plethora of multiscale, multi-wavelength, historical observations of Centaurus A to probe a unified view of feeding and feedback, which we show to be consistent with the chaotic cold accretion self-regulation scenario

Features of adenosine metabolism of mouse heart

Adenosine metabolism and transport were evaluated in the isolated perfused mouse heart and compared with the well-established model of isolated perfused guinea pig heart. Coronary venous release of adenosine under well-oxygenated conditions in the mouse exceeds that in the guinea pig threefold when related to tissue mass. Total myocardial adenosine production rate under this condition was approximately 2 nmol/min per gramme and similar in both species. Coronary resistance vessels of mice are highly sensitive to exogenous adenosine, and the threshold for adenosine-induced vasodilation is approximately 30 nmol/l. Adenosine membrane transport was largely insensitive to nitrobenzyl-thioinosine (NBTI) in mouse heart, which is in contrast to guinea pig and several other species. This indicates the dominance of NBTI-insensitive transporters in mouse heart. For future studies, the assessment of cytosolic and extracellular adenosine metabolism and its relationship with coronary flow will require the use of more effective membrane transport blockers

Protection from pulmonary ischemia-reperfusion injury by adenosine A2A receptor activation

<p>Abstract</p> <p>Background</p> <p>Lung ischemia-reperfusion (IR) injury leads to significant morbidity and mortality which remains a major obstacle after lung transplantation. However, the role of various subset(s) of lung cell populations in the pathogenesis of lung IR injury and the mechanisms of cellular protection remain to be elucidated. In the present study, we investigated the effects of adenosine A_2Areceptor (A_2AAR) activation on resident lung cells after IR injury using an isolated, buffer-perfused murine lung model.</p> <p>Methods</p> <p>To assess the protective effects of A_2AAR activation, three groups of C57BL/6J mice were studied: a sham group (perfused for 2 hr with no ischemia), an IR group (1 hr ischemia + 1 hr reperfusion) and an IR+ATL313 group where ATL313, a specific A_2AAR agonist, was included in the reperfusion buffer after ischemia. Lung injury parameters and pulmonary function studies were also performed after IR injury in A_2AAR knockout mice, with or without ATL313 pretreatment. Lung function was assessed using a buffer-perfused isolated lung system. Lung injury was measured by assessing lung edema, vascular permeability, cytokine/chemokine activation and myeloperoxidase levels in the bronchoalveolar fluid.</p> <p>Results</p> <p>After IR, lungs from C57BL/6J wild-type mice displayed significant dysfunction (increased airway resistance, pulmonary artery pressure and decreased pulmonary compliance) and significant injury (increased vascular permeability and edema). Lung injury and dysfunction after IR were significantly attenuated by ATL313 treatment. Significant induction of TNF-α, KC (CXCL1), MIP-2 (CXCL2) and RANTES (CCL5) occurred after IR which was also attenuated by ATL313 treatment. Lungs from A_2AAR knockout mice also displayed significant dysfunction, injury and cytokine/chemokine production after IR, but ATL313 had no effect in these mice.</p> <p>Conclusion</p> <p>Specific activation of A_2AARs provides potent protection against lung IR injury via attenuation of inflammation. This protection occurs in the absence of circulating blood thereby indicating a protective role of A_2AAR activation on resident lung cells such as alveolar macrophages. Specific A_2AAR activation may be a promising therapeutic target for the prevention or treatment of pulmonary graft dysfunction in transplant patients.</p