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In this work, we adapt a module for planetary formation within the hydrodynamic code fargo3d. Planetary formation is modelled by a solid core accretion scenario, with the core growing in oligarchic regime. The initial superficial density of planetesimals is proportional to the initial superficial density of gas in the disc. We include a numerical approach to describe the evolution of the eccentricity and the inclination of planetesimals during the formation. This approach impacts directly on the accretion rate of solids. When the core reaches a critical mass, gas accretion begins, following the original fargo scheme adapted to the fargo3d code. To exemplify how the module for planetary formation can be used, we investigate the migration of a planet in a 2D, locally isothermal gas disc with a prescribed accretion rate, analysing the time-scale involved in the planetary migration process along with the time-scale for planetary formation. The analysis reveals that the mass of the nucleus must be close to its critical value when crossing the ice line to avoid the planet's fall into the stellar envelope. This will allow enough time for the planet to initiate runaway gas accretion, leading to a rapid mass increase and entering type II planetary migration. [ABSTRACT FROM AUTHOR]

Purpose: The incidence of primary central nervous system lymphoma (PCNSL) is increasing. Therapeutic approaches remain controversial. An animal model that mimics the clinical situation would be useful for evaluating PCNSL biology and treatment., Experimental Design: Nude rats received intracerebral (caudate nucleus, n = 49) or intraventricular (n = 4) inoculation of human B-lymphoma cell line MC116. Two to five weeks after tumor inoculation, magnetic resonance imaging (MRI) was done (n = 24), and rat brains were assessed for pathology. Five rats each received whole-brain radiotherapy (WBRT, 20 Gy) or high-dose i.v. methotrexate (3 g/m2)., Results: Intracerebral tumors developed in 84% of evaluable animals with no pretreatment, 79% of rats pretreated with 4 Gy total body irradiation, and 92% of rats pretreated with cyclophosphamide (300 mg/m2). MRI showed abnormal T2 signal and gadolinium enhancement on T1-weighted images, consistent with tumor growth 19 to 24 days after inoculation. Tumor cells staining positively for B-lymphoma markers infiltrated within the inoculated hemisphere, along fiber tracks to the contralateral hemisphere, and along the subarachnoid space and ventricles. Tumors showed reactive gliosis. Intraventricular tumor cell injection resulted in periventricular parenchymal infiltration in both hemispheres. Radiation and methotrexate were effective in vitro, but only WBRT was clearly effective after 1 week in the intracerebral model., Conclusion: This model closely mimics human PCNSL in terms of imaging, histology, and treatment sensitivity and will be useful for the development of future therapeutic strategies for PCNSL.