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While it is well established that supermassive black holes (SMBHs) co-evolve with their host galaxy, it is currently less clear how lower mass black holes, so-called intermediate mass black holes (IMBHs), evolve within their dwarf galaxy hosts. In this paper, we present results on the evolution of a large sample of IMBHs from the NewHorizon simulation. We show that occupation fractions of IMBHs in dwarf galaxies are at least 50 percent for galaxies with stellar masses down to 1E6 Msun, but BH growth is very limited in dwarf galaxies. In NewHorizon, IMBH growth is somewhat more efficient at high redshift z = 3 but in general IMBH do not grow significantly until their host galaxy leaves the dwarf regime. As a result, NewHorizon under-predicts observed AGN luminosity function and AGN fractions. We show that the difficulties of IMBH to remain attached to the centres of their host galaxies plays an important role in limiting their mass growth, and that this dynamic evolution away from galactic centres becomes stronger at lower redshift., Comment: 15 pages, submitted to MNRAS

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In a population-based case-control study of breast cancer in Tianjin, China, involving 300 cases and 300 population controls interviewed during 1985-1986, a number of strong risk factors were identified. Although average age at menarche was late by Western standards in this developing country (14.4 years), it was clearly related to risk. Women with their first menstrual period at age 12 years or earlier had 80% greater risk than women who started at age 17 years or later. Age at first full-term pregnancy was also strongly related to risk, with women whose first birth after age 30 years having 3.2 times the risk of women whose first birth was under age 20 years. Other established breast cancer risk factors in Western populations (family history of breast cancer, a history of benign breast disease, and use of oral contraceptives late in reproductive life) were also risk factors in this population. Parity and duration of lactation were both strongly protective against breast cancer development in univariate analyses. These two variables were highly correlated with each other and with age at first full-term pregnancy. Although the effects of each variable dissipated somewhat in multivariate analysis, our data strongly suggest that both parity and lactation independently contribute to breast cancer risk.

Die gegenwartige Diskussion uber biologische Wirkungen ionisierender Strahlen auf Zellen und Organismen schliest das Thema „Hormesis“ ein. Luckey [25] behauptet, es bestehe kein Zweifel, das eine niedrige Strahlendosis anstatt unvermeidlichen Schaden eine allgemein „gunstige“ und/oder „stimulierende“, wenn nicht sogar lebensnotwendige Reizwirkung induziert und das sie sogar gegen hohere Dosen schutzt. Aber auch eine umfassende Belegsammlung ist noch keine Theorie. Hormesis wurde bereits in einem popularen Cartoon von Walt Disney „Mein Freund, das Atom“ dargestellt. Luckey [23, 24], Flemming [11], Fremlin [12], Feldmann [10] und Wachsmann [45] haben wenig mehr als Elemente aus Disneys Fantasie erlautert. Der Leser sei auf eine differenzierte Diskussion des Hormesis-Problems hingewiesen [38].

It is well known that non-absorbable ligatures and sutures applied to some tubular structures in the body tend to migrate. The special mode of migration of such material in the intestine, common bile duct, Fallopian tubes, and large arteries has been determined in detail. The present work concerns the behavior of ligatures applied to a tertiary bronchus, and the resultant effect upon the bronchial continuity, in dogs.The first branch (about 4 mm. in diameter) of the stem bronchus of the right lower lobe was exposed, and ligated with silk. In 9 dogs, it was singly ligated; in 8 other dogs it was ligated at 2 points and divided between the ligatures. After postoperative periods varying from 3 days to 6 months, the animals were killed and the region of ligation was examined grossly and microscopically (using serial microscopic sections).In every case of single ligation, before the 7th day, the thread cut through the bronchial wall at one point. The process continued, more or less gradually, until the ligatur...

Following the announcement by Carroll L. Birch 1 of the discovery that a hormonal disturbance exists in hemophilia which is temporarily relieved by parenteral administration of ovarian substances, the opportunity presented itself to us in a case of that disease to test the efficacy of ovarian extract for controlling dangerous spontaneous bleeding and to gather data of possible future assistance for safeguarding against persistently bleeding hemophiliac patients who need surgical operations. The potential value to surgery of such clinical applications of Birch's discovery is obvious. The data from this case are reported without waiting for more material, since the disease is uncommon 2 and prompt standardization of the surgical methods will require that data from many sources be pooled in the literature. Birch gave daily injections of ovarian extract for eight months to one person with hemophilia and abolished the abnormal tendency to bleeding during that period and for two

We investigate the correlation of star formation quenching with internal galaxy properties and environment by comparing observation and theoretical models. We first classify galaxies as the most massive “central” or “satellite” in each halo in order to investigate the environmental effect. For observed central galaxies, we are unable to determine whether star formation quenching is primarily connected with halo mass or stellar mass, because these two quantities are strongly correlated. For satellite galaxies, a nearly equal dependence on halo mass and stellar mass is seen. We find that theoretical models with AGN feedback reproduce the dependence on colours and specific star formation rates for central galaxies reasonably. However, the same models seriously fail to reproduce the star formation rates of satellite galaxies by over-quenching star formation via strong strangulation: satellite over-quenching problem .