Operation of an electron-bombardment ion source using various gases

An electron-bombardment ion thruster of the SERT 2 type was operated with xenon, krypton, argon, neon, nitrogen, helium, and carbon dioxide. The discharge performance with xenon, krypton, and argon was similar to that obtained previously with mercury. Mass spectrometer data indicated that the xenon contained no significant multiple ionization. Restriction of the beam area, with an associated decrease in discharge potential, was necessary to reduce multiple ionization with argon to a negligible level. This modification also resulted in more stable operation of the thruster. Performance with the remaining gases was poor because the basic thruster designed was optimized for operation with mercury

Sounds of silence: data for analysing muted safety voice in speech

Transcribed text from simulated hazards contains important content relevant for preventing harm. By capturing and analysing the content of speech when people raise (safety voice) or withhold safety concerns (safety silence), communication patterns may be identified for when individuals perceive risk, and safety management may be improved through identifying potential antecedents. This dataset contains transcribed speech from 404 participants (n students = 377; n female = 277, Age M (sd) = 22.897 (5.386)) engaged in a simulated hazardous scenario (walking across an unsafe plank), capturing 18,078 English words (M (sd) = 46.117 (37.559)). The data was collected through the Walking the plank paradigm (Noort et al, 2019), which provides a validated laboratory experiment designed for the direct observation of communication in response to hazardous scenarios that elicit safety concerns. Three manipulations were included in the design: hazard salience (salient vs not salient), responsibilities (clear vs diffuse) and encouragements (encouraged vs discouraged). Speech between two set timepoints in the hazardous scenario was transcribed based on video recordings and coded in terms of the extent to which speech involved safety voice or safety silence. Files contain i) a.csv containing the raw data, ii) a.csv providing variable description, iii) a Jupyter notebook (v. 3.7) providing the statistical code for the accompanying research article, iv) a.html version of the Jupyter notebook, v) a.html file providing the graph for the.html Jupyter notebook, vi) speech dictionaries, and vii) a copy of the electronic questionnaire. The data and supplemental files enable future research through providing a dataset in which participants can be distinguished in terms of the extent to which they are concerned and raise or withhold this. It enables speech and conversation analyses and the Jupyter notebook may be adapted to enable the parsing and coding of text using provided, existing and custom dictionaries. This may lead to the identification of communication patterns and potential interventions for unmuting safety voice. This data-in-brief is published alongside the research article: M. C. Noort, T.W. Reader, A. Gillespie. (2021). The sounds of safety silence: Interventions and temporal patterns unmute unique safety voice content in speech. Safety Science

The sounds of safety silence: interventions and temporal patterns unmute unique safety voice content in speech

Research shows that withholding safety concerns on encountering hazards – safety silence – is a critical contributor to accidents. Studies therefore aim to prevent accidental harm through interventions for reducing safety silence. Yet, the behaviour remains poorly understood, obstructing effective safety management: it is unclear to what extent safety silence involves muted safety voice (the partial withholding of safety concerns), and how muted safety voice can be recognised in speech, may be measured based on the degrees and types of safety voice (speaking up about safety), progresses over time, and may be optimally reduced. To improve safety management, this study proposes a conceptual model for the manifestation of safety silence and muted safety voice using a laboratory experiment (N = 404) to evaluate the implications for the effectiveness of three interventions (salient hazards, clear responsibilities, encouragements) across stages of a hazard. Results indicated that safety silence and muted safety voice are measurable in terms of the degree to which concerned people engage in five types of safety voice at different points in time, and we revealed this is important for safety management: interventions only unmute safety voice at unique hazard stages and for knowledge-based speech when people are concerned. This indicates that safety silence and muted safety voice are situated and can be recognised in nuanced speech, with interventions being most effective when timed appropriately and people have safety concerns to speak up about

Seasonal contribution of terrestrial organic matter and biological oxygen demand to the Baltic Sea from three contrasting river catchments

To examine the potential influence of terrestrially derived DOM on the Baltic Sea, a year-long study of dissolved organic matter (DOM) was performed in three river catchments in Sweden. One catchment drains into the Bothnian Sea, while two southern catchments drain into the Baltic proper. Dissolved organic carbon (DOC) concentrations were positively correlated with discharge from forested catchments over the year. While the overall concentrations of DOC were several times higher in the southern two catchments, higher discharge in the northern catchment resulted in the annual loadings of DOC being on the same order of magnitude for all three catchments. Biological oxygen demand (BOD) was used as a proxy for the lability of carbon in the system. The range of BOD values was similar for all three catchments, however, the ratio of BOD to DOC (an indication of the labile fraction) in Ume river was four times higher than in the southern two catchments. Total annual BOD loading to the Baltic Sea was twice as high in the northern catchment than in the two southern catchments. Lower winter temperatures and preservation of organic matter in the northern catchment combined with an intense spring flood help to explain the higher concentrations of labile carbon in the northern catchment. Lower lability of DOM as well as higher colour in the southern catchments suggest that wetlands (i.e. peat bogs) may be the dominant source of DOM in these catchments, particularly in periods of low flow. With climate change expected to increase precipitation events and temperatures across the region, the supply and quality of DOM delivered to the Baltic Sea can also be expected to change. Our results indicate that DOM supply to the Baltic Sea from boreal rivers will be more stable throughout the year, and potentially have a lower bioavailability

Safety sans frontières: an international safety culture model

The management of safety culture in international and culturally diverse organisations is a concern for many high-risk industries. Yet, research has primarily developed models of safety culture within Western countries, and there is a need to extend investigations of safety culture to global environments. We examined i) whether safety culture can be reliably measured within a single industry operating across different cultural environments, and ii) if there is an association between safety culture and national culture. The psychometric properties of a safety culture model developed for the air traffic management industry (ATM) were examined in 17 European countries from four culturally distinct regions of Europe (North, East, South, West). Participants were ATM operational staff (n = 5176) and management staff (n = 1230). Through employing multi-group confirmatory factor analysis, good psychometric properties of the model were established. This demonstrates, for the first time, that when safety culture models are tailored to a specific industry, they can operate consistently across national boundaries and occupational groups. Additionally, safety culture scores at both regional and national levels were associated with country-level data on Hofstede’s five national culture dimensions (collectivism, power distance, uncertainty avoidance, masculinity, and uncertainty avoidance). MANOVAs indicated safety culture to be most positive in Northern Europe, less so in Western and Eastern Europe, and least positive in Southern Europe. This indicates that national cultural traits may influence the development of organisational safety culture, with significant implications for safety culture theory and practice

The relationship between national culture and safety culture: implications for international safety culture assessments

In this article we examine the relationship between safety culture and national culture, and the implications of this relationship for international safety culture assessments. Focussing on Hofstede’s uncertainty avoidance (UA) index, a survey study of 13,616 Air Traffic Management (ATM) employees in 21 European countries found a negative association between safety culture and national norm data for uncertainty avoidance. This is theorized to reflect the influence of national tendencies for uncertainty avoidance upon attitudes and practices for managing safety (e.g., anxiety on risk; reliance on protocols; concerns over reporting incidents; openness to different perspectives). The relationship between uncertainty avoidance and safety culture is likely to have implications for international safety culture assessments. Specifically, benchmarking exercises will consistently indicate safety management within organizations in high UA countries to be poorer than low UA countries due to the influence of national culture upon safety practices, which may limit opportunities for identifying and sharing best practice. We propose the use of safety culture against international group norms (SIGN) scores to statistically adjust for the influence of uncertainty avoidance upon safety culture data, and to support the identification of safety practices effective and particular to low or high UA cultures

Licensing MLH1 sites for crossover during meiosis

During meiosis, homologous chromosomes synapse and recombine at sites marked by the binding of the mismatch repair protein MLH1. In hexaploid wheat, the Ph1 locus has a major effect on whether crossover occurs between homologues or between related homoeologues. Here we report that—in wheat–rye hybrids where homologues are absent—Ph1 affects neither the level of synapsis nor the number of MLH1. Thus in the case of wheat–wild relative hybrids, Ph1 must affect whether MLH1 sites are able to progress to crossover. The observed level of synapsis implies that Ph1 functions to promote homologue pairing rather than suppress homoeologue pairing in wheat. Therefore, Ph1 stabilises polyploidy in wheat by both promoting homologue pairing and preventing MLH1 sites from becoming crossovers on paired homoeologues during meiosis