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1.
Astron Astrophys Rev ; 31(1): 4, 2023.
Article in English | MEDLINE | ID: mdl-38115816

ABSTRACT

Understanding the physical mechanisms that control galaxy formation is a fundamental challenge in contemporary astrophysics. Recent advances in the field of astrophysical feedback strongly suggest that cosmic rays (CRs) may be crucially important for our understanding of cosmological galaxy formation and evolution. The appealing features of CRs are their relatively long cooling times and relatively strong dynamical coupling to the gas. In galaxies, CRs can be close to equipartition with the thermal, magnetic, and turbulent energy density in the interstellar medium, and can be dynamically very important in driving large-scale galactic winds. Similarly, CRs may provide a significant contribution to the pressure in the circumgalactic medium. In galaxy clusters, CRs may play a key role in addressing the classic cooling flow problem by facilitating efficient heating of the intracluster medium and preventing excessive star formation. Overall, the underlying physics of CR interactions with plasmas exhibit broad parallels across the entire range of scales characteristic of the interstellar, circumgalactic, and intracluster media. Here we present a review of the state-of-the-art of this field and provide a pedagogical introduction to cosmic ray plasma physics, including the physics of wave-particle interactions, acceleration processes, CR spatial and spectral transport, and important cooling processes. The field is ripe for discovery and will remain the subject of intense theoretical, computational, and observational research over the next decade with profound implications for the interpretation of the observations of stellar and supermassive black hole feedback spanning the entire width of the electromagnetic spectrum and multi-messenger data.

2.
Comb Chem High Throughput Screen ; 16(6): 463-72, 2013 Jul.
Article in English | MEDLINE | ID: mdl-23410040

ABSTRACT

The evaluation of the relationships between the hormones involved in the urogenital tract cancer, including bladder, kidney, prostate, and testis, could prove important from diagnostic point of view. The determination of the steroid hormone profiles may likely provide a biomarker for discrimination of hormone-related diseases, as well as for differentiation of healthy volunteers from patients with cancer. The aim of the study was to demonstrate the changes in the steroid hormone profile (comprising corticosteroids, androgens and progesterone) in the urine of patients with the urogenital tract cancer versus urine from healthy subjects. A reliable analytical method based on liquid chromatography coupled with mass spectrometry was successfully applied to determine the urinary profiles of 6 endogenous steroids: cortisol, cortisone, corticosterone, testosterone, epitestosterone and progesterone for 92 urogenital tract cancer patients and 100 healthy controls. The obtained data was further evaluated by in-depth chemometric analysis, including the applied standardized Kennard-Stone's algorithm to pre-process the data. Mann-Whitney U test revealed statistically significant (p <0.05) differences in concentration of androgens and progesterone in the case of bladder cancer for male and female population, for male also cortisol and cortisone levels were significantly increased. PCA analysis proved a reasonable trend for differentiating healthy and cancer patients, and finally, applying PLS-DA model we were able to correctly classify 80.56%of cancer patients. Our results indicate that steroid hormone profile determination could be a promising approach for early diagnosis of urogenital tract cancer. However our preliminary results require an extension both in patient number and steroid profile.


Subject(s)
Biomarkers, Tumor/urine , Gonadal Steroid Hormones/urine , Urogenital Neoplasms/diagnosis , Urogenital Neoplasms/urine , Adult , Chromatography, Liquid , Female , Humans , Male , Mass Spectrometry
3.
Philos Trans A Math Phys Eng Sci ; 363(1828): 655-65; discussion 665, 2005 Mar 15.
Article in English | MEDLINE | ID: mdl-15681284

ABSTRACT

Jets and winds are significant channels for energy loss from accreting black holes. These outflows mechanically heat their surroundings, through shocks as well as gentler forms of heating. We discuss recent efforts to understand the nature and distribution of mechanical heating by central active galactic nuclei (AGN) in clusters of galaxies, using numerical simulations and analytic models. Specifically, we will discuss whether the relatively gentle 'effervescent heating' mechanism can compensate for radiative losses in the central regions of clusters, and account for the excess entropy observed at larger radii. J. Binney discusses the possible role of violent, episodic heating by AGN in clusters.


Subject(s)
Astronomy/methods , Entropy , Extraterrestrial Environment , Hot Temperature , Models, Theoretical , Physical Phenomena , Physics , Radiation
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