Linear Amplifier Breakdown and Concentration Properties of a Gaussian Field Given that its L2\bm{L^2}-Norm is Large

In the context of linear amplification for systems driven by the square of a Gaussian noise, we investigate the realizations of a Gaussian field in the limit where its $L^2$-norm is large. Concentration onto the eigenspace associated with the largest eigenvalue of the covariance of the field is proved. When the covariance is trace class, the concentration is in probability for the $L^2$-norm. A stronger concentration, in mean for the sup-norm, is proved for a smaller class of Gaussian fields, and an example of a field belonging to that class is given. A possible connection with Bose-Einstein condensation is briefly discussed.Comment: REVTeX file, 11 pages, 1 added paragraph in the introduction, 2 added references, minor modifications in the text and abstract, submitted to J. Stat. Phy

Decreased TNF-α synthesis by macrophages restricts cutaneous immunosurveillance by memory CD4+ T cells during aging

Immunity declines during aging, however the mechanisms involved in this decline are not known. In this study, we show that cutaneous delayed type hypersensitivity (DTH) responses to recall antigens are significantly decreased in older individuals. However, this is not related to CC chemokine receptor 4, cutaneous lymphocyte-associated antigen, or CD11a expression by CD4+ T cells or their physical capacity for migration. Instead, there is defective activation of dermal blood vessels in older subject that results from decreased TNF-α secretion by macrophages. This prevents memory T cell entry into the skin after antigen challenge. However, isolated cutaneous macrophages from these subjects can be induced to secrete TNF-α after stimulation with Toll-like receptor (TLR) 1/2 or TLR 4 ligands in vitro, indicating that the defect is reversible. The decreased conditioning of tissue microenvironments by macrophage-derived cytokines may therefore lead to defective immunosurveillance by memory T cells. This may be a predisposing factor for the development of malignancy and infection in the skin during aging

Neutron scattering instrumentation at the Research Reactor BER II

BENSC Instrumentierungsbroschür

Neuropsychobiological aspects, comorbidity patterns and dimensional models in borderline personality disorder

Borderline personality disorder (BPD) is a comorbid and disabling condition with high prevalence in psychiatric settings. The pathogenesis of BPD involves complex interactions among genetic, neurobiological and environmental factors, resulting in multiple core symptom domains such as emotional dysregulation, impulse dyscontrol, aggression, cognitive dysfunctions and dissociative states. Neurobiological studies show that symptoms and behaviors of BPD are partly associated with alterations in glutamatergic, dopaminergic and serotonergic systems. In addition, neuroimaging studies in BPD patients indicate differences in the volume and activity of specific brain regions related to emotion and impulse control, such as the prefrontal and cingulate cortex, amygdala and hippocampus. Neurobiological alterations are related to cognitive disturbances in patients with BPD and neuropsychological tests have shown abnormalities of memory, attention, language, and executive functions. The aim of the present review is to provide an updated overview of the main neuropsychobiological aspects of BPD and their relation to clinical symptoms, comorbidity patterns and dimensional models

BENSC experimental reports 2006

BENSC Experimental Reports 200

Faseroptischer Feldsensor. Teilvorhaben: Faser-Chip-Kopplung Abschlussbericht

Available from TIB Hannover: DtF QN1(83,25) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEBundesministerium fuer Bildung und Forschung (BMBF), Bonn (Germany)DEGerman

Neutron-scattering. Instrumentation at the research reactor BER II

The BER II research reactor, cold source and neutron guides - the instruments of BENSC - an overview; Instrument sites in experiment hall and neutron guide hall - description of the diffractometers. (orig./HP)SIGLEAvailable from TIB Hannover: ZA 4746(533) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman