25 research outputs found
Is it possible to recover information from the black-hole radiation?
In the framework of communication theory, we analyse the gedanken experiment
in which beams of quanta bearing information are flashed towards a black hole.
We show that stimulated emission at the horizon provides a correlation between
incoming and outgoing radiations consisting of bosons. For fermions, the
mechanism responsible for the correlation is the Fermi exclusion principle.
Each one of these mechanisms is responsible for the a partial transfer of the
information originally coded in the incoming beam to the black--hole radiation.
We show that this process is very efficient whenever stimulated emission
overpowers spontaneous emission (bosons). Thus, black holes are not `ultimate
waste baskets of information'.Comment: 9 pages (2 figures available upon request), CERN-TH 6811/93, (LateX
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The molecular hallmarks of primary and secondary vitreoretinal lymphoma
Vitreoretinal lymphoma (VRL) is a rare subtype of diffuse large B-cell lymphoma (DLBCL) considered a variant of primary central nervous system lymphoma (PCNSL). Diagnosis of VRL requires examination of vitreous fluid, but cytologic differentiation from uveitis remains difficult. Due to its rarity and difficulty in obtaining diagnostic material, little is known about the genetic profile of VRL. The aim of our study was to investigate the mutational profile of a large series of primary and secondary VRL. Targeted next generation sequencing using a custom panel containing the most frequent mutations in PCNSL was performed on 34 vitrectomy samples of 31 patients with VRL and negative controls with uveitis. In a subset of cases, genome-wide copy number alterations (CNA) were assessed using the Oncoscan platform. Mutations in MYD88 (74%), PIM1 (71%), CD79B (55%), IGLL5 (52%), TBL1XR1 (48%), ETV6 (45%) and 9p21/CDKN2A deletions (85%) were the most common alterations, with similar frequencies in primary (15), synchronous (3) or secondary (13) VRL. This mutational spectrum is similar to MYD88mut/CD79Bmut (MCD or cluster 5) DLBCL with activation of Toll-like and B-cell receptor pathways and CDKN2A loss, confirming their close relationship. Oncoscan analysis demonstrated a high number of CNAs (mean 18.6/case). Negative controls lacked mutations or CNAs. Using cell free DNA of vitreous fluid supernatant, mutations present in cellular DNA were reliably detected in all examined cases. Mutational analysis is a highly sensitive and specific tool for the diagnosis of VRL and can also be applied successfully to cell free DNA derived from the vitreous.Copyright © 2021 American Society of Hematology
Trust in governance networks: Its impacts on outcomes
__Abstract__
Governance networks are characterized by complex interaction and decision making, and much uncertainty. Surprisingly, there is very little research on the impact of trust in achieving results in governance networks. This article asks two questions: (a) Does trust influence the outcomes of environmental projects? and (b) Does active network management improve the level of trust in networks? The study is based on a Web-based survey of respondents involved in environmental projects. The results indicate that trust does matter for perceived outcomes and that network management strategies enhance the level of trust
Tuberöse Sklerose: eine interdisziplinäre Diagnose [Tuberous sclerosis: an interdisciplinary diagnosis]
Tuberous sclerosis is a relatively rare disease, but it often takes a progressive and severe course. We wish to demonstrate the typical changes in a patient with tuberous sclerosis and their relevance for the ophthalmologist.
Ophthalmologic evaluation including funduscopy, 30 degree perimetry and fundus photography and clinical course of a 40-year-old man are described. We observed an elevated, multinodular, opaque hamartoma resembling mulberries, approximately (1/3)-(1/2) PD large, at the temporal superior arc with corresponding visual field defects.
An ophthalmologist should always think of a tuberous sclerosis as a differential diagnosis when confronted with a retinal hamartoma. Other characteristic ophthalmological findings include facial and eyelid angiofibromas, coloboma of the iris, lens and choroid, strabismus, poliosis of the eyelashes, papilloedema and sector iris depigmentation. Clinical diagnosis of tuberous sclerosis is in most cases relatively easy; however, an interdisciplinary cooperation is needed
Diagnostik und Therapie der choroidalen Lymphome
Photograph of a Native American wall mural