157 research outputs found
An overview of jets and outflows in stellar mass black holes
In this book chapter, we will briefly review the current empirical
understanding of the relation between accretion state and and outflows in
accreting stellar mass black holes. The focus will be on the empirical
connections between X-ray states and relativistic (`radio') jets, although we
are now also able to draw accretion disc winds into the picture in a systematic
way. We will furthermore consider the latest attempts to measure/order jet
power, and to compare it to other (potentially) measurable quantities, most
importantly black hole spin.Comment: Accepted for publication in Space Science Reviews. Also to appear in
the Space Sciences Series of ISSI - The Physics of Accretion on to Black
Holes (Springer Publisher
The balance of power: accretion and feedback in stellar mass black holes
In this review we discuss the population of stellar-mass black holes in our
galaxy and beyond, which are the extreme endpoints of massive star evolution.
In particular we focus on how we can attempt to balance the available accretion
energy with feedback to the environment via radiation, jets and winds,
considering also possible contributions to the energy balance from black hole
spin and advection. We review quantitatively the methods which are used to
estimate these quantities, regardless of the details of the astrophysics close
to the black hole. Once these methods have been outlined, we work through an
outburst of a black hole X-ray binary system, estimating the flow of mass and
energy through the different accretion rates and states. While we focus on
feedback from stellar mass black holes in X-ray binary systems, we also
consider the applicability of what we have learned to supermassive black holes
in active galactic nuclei. As an important control sample we also review the
coupling between accretion and feedback in neutron stars, and show that it is
very similar to that observed in black holes, which strongly constrains how
much of the astrophysics of feedback can be unique to black holes.Comment: To be published in Haardt et al. Astrophysical Black Holes. Lecture
Notes in Physics. Springer 201
Kinin b(1) receptor in adipocytes regulates glucose tolerance and predisposition to obesity
BACKGROUND: Kinins participate in the pathophysiology of obesity and type 2 diabetes by mechanisms which are not fully understood. Kinin B(1) receptor knockout mice (B(1) (-/-)) are leaner and exhibit improved insulin sensitivity. METHODOLOGY/PRINCIPAL FINDINGS: Here we show that kinin B(1) receptors in adipocytes play a role in controlling whole body insulin action and glucose homeostasis. Adipocytes isolated from mouse white adipose tissue (WAT) constitutively express kinin B(1) receptors. In these cells, treatment with the B(1) receptor agonist des-Arg(9)-bradykinin improved insulin signaling, GLUT4 translocation, and glucose uptake. Adipocytes from B(1) (-/-) mice showed reduced GLUT4 expression and impaired glucose uptake at both basal and insulin-stimulated states. To investigate the consequences of these phenomena to whole body metabolism, we generated mice where the expression of the kinin B(1) receptor was limited to cells of the adipose tissue (aP2-B(1)/B(1) (-/-)). Similarly to B(1) (-/-) mice, aP2-B(1)/B(1) (-/-) mice were leaner than wild type controls. However, exclusive expression of the kinin B(1) receptor in adipose tissue completely rescued the improved systemic insulin sensitivity phenotype of B(1) (-/-) mice. Adipose tissue gene expression analysis also revealed that genes involved in insulin signaling were significantly affected by the presence of the kinin B(1) receptor in adipose tissue. In agreement, GLUT4 expression and glucose uptake were increased in fat tissue of aP2-B(1)/B(1) (-/-) when compared to B(1) (-/-) mice. When subjected to high fat diet, aP2-B(1)/B(1) (-/-) mice gained more weight than B(1) (-/-) littermates, becoming as obese as the wild types. CONCLUSIONS/SIGNIFICANCE: Thus, kinin B(1) receptor participates in the modulation of insulin action in adipocytes, contributing to systemic insulin sensitivity and predisposition to obesity
The need for communication between clinicians and pathologists in the context of oral and maxillofacial diseases
Good communication between clinicians and pathologists is a vital element in the diagnostic process, and poor communication can adversely affect patient care. There is a lack of research about communication in diagnostic oral and maxillofacial pathology. This narrative review explores different aspects of the quality of communication between clinicians and oral pathologists, with a focus on the diagnosis of oral and maxillofacial diseases. An electronic search was carried out in MEDLINE through the PubMed, Scopus, and Embase databases up to April 2021. No studies reporting communication, its adequacy or the required skills between clinicians and pathologists in oral diagnosis were found. According to studies published in medicine, strategies for improving communication skills include clinician-pathologist collaboration; a well-formatted, clear and thorough report; training in communication skills; and patient-centered care. Further studies evaluating the current practices and quality in oral and maxillofacial pathology are required to identify barriers and encourage optimal communication to facilitate diagnosis, as well as patient safety
Fire management and the nesting of Athene cunicularia (Aves, Strigidae) in grasslands in central Cerrado, Brazil
Apparent digestibility of simplified and semi-simplified diets, with and without addition of enzymes, and nutritional value of fibrous sources for rabbits
Lodos de esgoto alcalinizados em solos do estado do Paraná: taxa de aplicação máxima anual e comparação entre métodos para recomendação agrícola
Composição química e digestibilidade ruminal in situ da forragem de quatro espécies do gênero Brachiaria
Efeito da revegetação e da adubação de área degradada na fertilidade do solo e nas características da palhada
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