23 research outputs found
The extragalactic background and its fluctuations in the far-infrared wavelengths
A Cosmic Far-InfraRed Background (CFIRB) has long been predicted that would
traces the intial phases of galaxy formation. It has been first detected by
Puget et al.(1996) using COBE data and has been later confirmed by several
recent studies (Fixsen et al. 1998, Hauser et al. 1998, Lagache et al. 1999).
We will present a new determination of the CFIRB that uses for the first time,
in addition to COBE data, two independent gas tracers: the HI survey of
Leiden/Dwingeloo (hartmann, 1998) and the WHAM H survey (Reynolds et
al 1998). We will see that the CFIRB above 100 micron is now very well
constrained. The next step is to see if we can detect its fluctuations. To
search for the CFIRB fluctuations, we have used the FIRBACK observations.
FIRBACK is a deep cosmological survey conducted at 170 micron with ISOPHOT
(Dole et al., 2000). We show that the emission of unresolved extra-galactic
sources clearly dominates, at arcminute scales, the background fluctuations in
the lowest galactic emission regions. This is the first detection of the CFIRB
fluctuations.Comment: To appear in "ISO Surveys of a Dusty Universe", Workshop at Ringberg
Castle, November 8 - 12, 199
Communication for Peaceful Social Change and Global Citizenry
The adoption of the 17 Sustainable Development Goals (SDGs) by the United Nations (UN) in 2015
represents a universal call to action involving multiple international actors for the purpose of eradicating
poverty, improving living conditions and promoting peace. This entry provides a theoretical overview of
the contributions of scholars and practitioners who highlight the importance of a transformative,
educational and emancipatory communication by different social actors to establish the main lines of
action for the 2030 Agenda for Sustainable Development. This communicative model involves the
coordination of actors and strategies, both short- and long-term, cross-cutting actions and discourses to
build social, cultural and political settings based on the criteria of peace, equality, social justice and
human rights. Specifically, this entails a contribution to the objectives set out in SDG 16, “Peace, Justice
and Strong Institutions”, given that the proposed theoretical framework is grounded in Communication for
Peace and Communication for Social Change, and includes a systematization of different strategies and
experiences from a variety of social issuers, mainly institutions, non-governmental organizations (NGOs)
or social movements, aimed at promoting peaceful and inclusive societies. Specifically, communication
for peaceful social change and global citizenry contributes to the achievement of specific SDG 16
objectives, particularly 16.1: Significantly reduce all forms of violence... [...
Recommended from our members
Diverse processing underlying frequency integration in midbrain neurons of barn owls
Emergent response properties of sensory neurons depend on circuit connectivity and somatodendritic processing. Neurons of the barn owl's external nucleus of the inferior colliculus (ICx) display emergence of spatial selectivity. These neurons use interaural time difference (ITD) as a cue for the horizontal direction of sound sources. ITD is detected by upstream brainstem neurons with narrow frequency tuning, resulting in spatially ambiguous responses. This spatial ambiguity is resolved by ICx neurons integrating inputs over frequency, a relevant processing in sound localization across species. Previous models have predicted that ICx neurons function as point neurons that linearly integrate inputs across frequency. However, the complex dendritic trees and spines of ICx neurons raises the question of whether this prediction is accurate. Data from in vivo intracellular recordings of ICx neurons were used to address this question. Results revealed diverse frequency integration properties, where some ICx neurons showed responses consistent with the point neuron hypothesis and others with nonlinear dendritic integration. Modeling showed that varied connectivity patterns and forms of dendritic processing may underlie observed ICx neurons' frequency integration processing. These results corroborate the ability of neurons with complex dendritic trees to implement diverse linear and nonlinear integration of synaptic inputs, of relevance for adaptive coding and learning, and supporting a fundamental mechanism in sound localization