New limits on radiative sterile neutrino decays from a search for single photons in neutrino interactions

It has been recently shown that excess events observed by the LSND and MiniBooNE neutrino experiments could be interpreted as a signal from the radiative decay of a heavy sterile neutrino \nu_h produced in \nu_\mu neutral current-like interactions. If the \nu_h exist, it would be also produced by the \nu_\mu beam from the CERN SPS in the neutrino beam line shielding. The \nu_h's would penetrate the shielding and be observed through the decay \nu_h -> \nu \gamma, followed by the photon conversion into e+e- pair in the active target of the NOMAD detector. The \nu_h's could be also produced in the iron of the magnetic spectrometer of the CHORUS detector, located just in front of NOMAD. Considering these two sources of \nu_h's we set new constraints on \nu_h properties and exclude part of the LSND/MiniBooNE \nu_h parameter space using bounds on single photons production in neutrino reactions recently reported by the NOMAD collaboration. We find that broad bands in the parameter space are still open for more sensitive searches for the \nu_h in future neutrino experiments.Comment: 10 pages, 5 figures. Revised version to appear in PLB. Discussion of dominant NC-like production of \nu_h's adde

What are analog bulletin boards used for today?:Analysing media uses, intermediality and technology affordances in Swedish bulletin board messages using a citizen science approach

Analog bulletin boards are omnipresent in Swedish urban areas, yet little systematic knowledge about this communication medium exists. In the shadow of the rapid emergence of digital media the analog bulletin board has received less attention than its digital successors, many of them having incorporated similar functionality with novel technical solutions. In this study we used a citizen science method to collect 1167 messages from bulletin boards around Sweden aided by school children and teachers, with the purpose of shedding new light on what is communicated on the boards, by whom, using what types of technologies and in what way the messages refer to other media. Results show that the most common messages are invitations to events, such as concerts, lectures and sports events, followed by buy-and-sell ads for goods and services. The most frequent sender is an association, for example NGOs, sports associations or religious communities. Almost half of the sampled messages were professionally printed, about forty per cent were made by home printers. Only six per cent of the messages were handwritten, almost exclusively by private persons as senders. Moreover, we show how the analog bulletin board has adapted to recent changes in media technology-a media landscape which is saturated with electronic- and mobile media. Further, the bulletin board still holds a firm place in a media ecology where local communication is in demand, and exists in parallel with electronic media. Close to forty percent of the messages contained hyperlinks to web pages and we found (and removed for anonymization purposes) more than six hundred phone numbers from the dataset.</p

Methane in the Baltic and North Seas and a reassessment of the marine emissions of methane

During three measurement campaigns on the Baltic and North Seas, atmospheric and dissolved methane was determined with an automated gas chromatographic system. Area-weighted mean saturation values in the sea surface waters were 113 ± 5% and 395 ± 82% (Baltic Sea, February and July 1992) and 126 ± 8% (south central North Sea, September 1992). On the bases of our data and a compilation of literature data the global oceanic emissions of methane were reassessed by introducing a concept of regional gas transfer coefficients. Our estimates computed with two different air-sea exchange models lie in the range of 11-18 Tg CH4 yr-1. Despite the fact that shelf areas and estuaries only represent a small part of the world's ocean they contribute about 75% to the global oceanic emissions. We applied a simple, coupled, three-layer model to numerically simulate the time dependent variation of the oceanic flux to the atmosphere. The model calculations indicate that even with increasing tropospheric methane concentration, the ocean will remain a source of atmospheric methane

“You MAY take the note home an’… well practise just that” – Children’s interaction in contextualizing music teaching

ABSTRACT The article takes ‘music as symbol’ as its analytical point of departure, described by Jorgensen (2003). In doing so, we stress the role of symbolic functioning in music, focusing at how children understand and make sense of music in talk and practice. The aim of this text is to theoretically explore the nature of dialogical music education. In order to do so, we reuse empirical data from a previous study. These data contain four children’s instructional interaction in a teaching activity, that is, the task to teach each other singing songs. Further, we examine our data through the lenses of two theoretical concepts, based on communication theory: double dialogicality and communicative formality. Our interactional data point at the contextual nature of musical sense making. The children’s communication was not only merely interpersonal in nature. Rather, it also clearly referred to an embedded cultural context that existed beyond the local interactional context. This article illustrates how such kind of music-educational sense making is socially constructed in action. Keywords: children, singing, context, teaching, interaction, music as symbol, double dialogicalit

Ophrys fusca and Ophrys dyris (Orchidaceae) – constancy of tetraploidy amongst populations in Central Portugal

Ophrys is amongst the best known orchid genera and is an established system for the study of pollinatormediated floral evolution. Two species, Ophrys fusca s.l. and Ophrys dyris (= O. omegaifera subsp. dyris) belonging to Ophrys section Pseudophrys are the focus of this study. In the context of an integrative study of morphological and genetic diversity of O. fusca and O. dyris, genome size (GS) and cytotype diversity were surveyed from Portuguese populations. Flow cytometry methods were used to assess GS, and subsequently determine the ploidy level of 67 specimens, including the species and putative hybrids. Cytotypes were also confirmed based on chromosome counts from the roots of two specimens, one of each species. Constancy of nuclear DNA content (1C = 11.19 pg) and ploidy level (2n =4x = 72, 74) was documented among all the individuals analysed. Implications are considered, in terms of interpreting the origin and predicting the persistence of putative hybrids

Democratic education and dialogic pedagogy: synergies and dissonances

This paper is a republication of an interview between Tina Kullenberg and Ana Marjanovic-Shane, published in the EARLI SIG 25 Interview Series: ”The role of theory and philosophy in Educational Science” (Kullenberg &amp; Marjanovic-Shane, 2020)[2]. In the interview, the authors discuss the reasons democratic schools sometimes support but other times do not support or even limit dialogic pedagogy. In the interview conducted by Tina Kullenberg, Marjanovic-Shane makes a distinction between schooling and education. Finally, in the face of global development, while sharing her comprehensive experiences over time and cultures, Marjanovic-Shane critically reflects on predominant approaches to education and the organization of schooling

The Baltic Sea Tracer Release Experiment. Part I: Mixing rates

In this study, results from the Baltic Sea Tracer Release Experiment (BATRE) are described, in which deep water mixing rates and mixing processes in the central Baltic Sea were investigated. In September 2007, an inert tracer gas (CF3SF5) was injected at approximately 200 m depth in the Gotland Basin, and the subsequent spreading of the tracer was observed during six surveys until February 2009. These data describe the diapycnal and lateral mixing during a stagnation period without any significant deep water renewal due to inflow events. As one of the main results, vertical mixing rates were found to dramatically increase after the tracer had reached the lateral boundaries of the basin, suggesting boundary mixing as the key process for basin-scale vertical mixing. Basin-scale vertical diffusivities were of the order of 10−5 m2 s−1 (about 1 order of magnitude larger than interior diffusivities) with evidence for a seasonal and vertical variability. In contrast to tracer experiments in the open ocean, the basin geometry (hypsography) was found to have a crucial impact on the vertical tracer spreading. The e-folding time scale for deep water renewal due to mixing was slightly less than 2 years, the time scale for the lateral homogenization of the tracer patch was of the order of a few months. Key Points: Mixing rates in the Gotland Basin are dominated by boundary mixing processes; The time scale for Gotland Basin deep water renewal is approximately 2 years; Mixing rates determined from the tracer CF3SF