148 research outputs found
Adsorption and two-body recombination of atomic hydrogen on He-He mixture films
We present the first systematic measurement of the binding energy of
hydrogen atoms to the surface of saturated He-He mixture films.
is found to decrease almost linearly from 1.14(1) K down to 0.39(1) K, when the
population of the ground surface state of He grows from zero to
cm, yielding the value K cm
for the mean-field parameter of H-He interaction in 2D. The experiments
were carried out with overall He concentrations ranging from 0.1 ppm to 5 %
as well as with commercial and isotopically purified He at temperatures
70...400 mK. Measuring by ESR the rate constants and for
second-order recombination of hydrogen atoms in hyperfine states and we
find the ratio to be independent of the He content and to
grow with temperature.Comment: 4 pages, 4 figures, all zipped in a sigle file. Submitted to Phys.
Rev. Let
Developmental experiences of elite female youth soccer players
To advance the literature on talent development within elite female athletes, this study investigated the developmental experiences of elite youth female soccer players. We adopted an interpretive approach where four players (M age = 16.75) were initially interviewed to gain a retrospective understanding of their development as soccer players. Subsequent fieldwork and further interviews were used to gain a current and prospective understanding of their development as players. Data were subjected to an inductive analysis, composite sequence analysis and a collaborative member checking process to co-construct a sequential, developmental understanding of the players' experiences within elite youth soccer. The findings suggested that the soccer experience of fathers and/or older brothers played a significant role in the players' development. Soccer fathers were able to provide advice and guidance specific to the needs of their daughter-player at different age ranges whilst at the same time reinforcing the importance of coach–player relationships. Soccer brothers acted as either positive or negative models for their sister-players and served as a source of information about key career choices. Friends inside (termed as soccer friends) and outside (termed as non-soccer friends) soccer played a significant role in helping players to lead the disciplined lifestyle required of an elite youth soccer player. Finally, findings suggest that self-regulation and adaptive volitional behaviours appear to be key intra-individual factors associated with talent development in female soccer. These findings are considered in the light of previous talent development literature alongside directions for future research
Direct Microscopic Study of Doubly Polarized Atomic Hydrogen by Electron-Spin Resonance
By means of ESR in a high magnetic field the hyperfine states of a gas of spin-polarized atomic hydrogen are directly probed. This allows a direct determination of the spin-state populations and nuclear polarization. The unusual ESR line shape is attributed to field inhomogeneities. The temperature of the gas was determined by use of ESR with no indication of nonequilibrium due to Kapitza resistance. Recombination rates between hyperfine states could be determined
On ethically solvent leaders : the roles of pride and moral identity in predicting leader ethical behavior.
The popular media has repeatedly pointed to pride as one of the key factors motivating leaders to behave unethically. However, given the devastating consequences that leader unethical behavior may have, a more scientific account of the role of pride is warranted. The present study differentiates between authentic and hubristic pride and assesses its impact on leader ethical behavior, while taking into consideration the extent to which leaders find it important to their self-concept to be a moral person. In two experiments we found that with higher levels of moral identity, authentically proud leaders are more likely to engage in ethical behavior than hubristically proud leaders, and that this effect is mediated by leaders’ motivation to act selflessly. A field survey among organizational leaders corroborated that moral identity may bring the positive effect of authentic pride and the negative effect of hubristic pride on leader ethical behavior to the forefront
Preventing Violence in Seven Countries: Global Convergence in Policies
Do governments take the measures that are supported by the best scientific evidence available? We present a brief review of the situation in: Australia, Canada, Germany, the Netherlands, Spain, the United Kingdom, and the United States. Our findings show surprisingly similar developments across countries. While all seven countries are moving towards evidence-based decision making regarding policies and programs to prevent violence, there remain a number of difficulties before this end can be achieved. For example, there continue to be few randomized controlled trials or rigorous quasi-experimental studies on aggression and violence. Results from experimental research are essential to both policy makers and researchers to determine the effectiveness of programs as well as increase our knowledge of the problem. Additionally, all noted that media attention for violence is high in their country, often leading to management by crisis with the result that policies are not based on evidence, but instead seek to appease public outrage. And perhaps because of attendant organizational problems (i.e., in many countries violence prevention was not under the guise of one particular agency or ministry), most have not developed a coordinated policy focusing on the prevention of violence and physical aggression. It is hypothesized that leaders in democratic countries, who must run for election every 4 to 6 years, may feel a need to focus on short-term planning rather than long-term preventive policies since the costs, but not the benefits for the latter would be incurred while they still served in office. We also noted a general absence of expertise beyond those within scientific circles. The need for these ideas to be more widely accepted will be an essential ingredient to real and sustaining change. This means that there must be better communication and increased understanding between researchers and policy makers. Toward those ends, the recent establishment of the Campbell Collaboration, formed to provide international systematic reviews of program effectiveness, will make these results more available and accessible to politicians, administrators and those charged with making key policy decision
Vuurwerkletsel in Zuidwest-Nederland rond de jaarwisseling 2017-2018
OBJECTIVE: To report the number of patients with firework-related injuries treated in December 2017 and January 2018 in a hospital in the south-west Netherlands trauma region, and to provide details about the types of firework used and the specific injuries. DESIGN: A prospective multicentre cohort study (NTR6793). METHODS: Patients of all ages with firework-related injuries were eligible for inclusion. The injury had to have been sustained between 1 December 2017 and 31 January 2018, and treated at a hospital in the south-west Netherlands trauma region (approximately 2.5 million inhabitants). Data were extracted from patients' medical files and additional information was obtained from patient interviews. RESULTS: Fifty-four patients were included. The majority were male (93%) and the median age was 15 years. Twenty-five (46%) patients were bystanders and 12 (22%) were injured by illegal fireworks. Fifty patients were injured by bangers (n=22) or decorative fireworks (n=28). The patients had a total of 79 injuries, of which 29 (37%) were localised to the upper extremity and 19 (24%) to the eyes. Most upper extremity injuries were burns (69%), primarily partial thickness. Of the eye injuries, 14 were caused by blunt trauma, seven by chemical trauma, and one by penetrating trauma. Three patients sustained indirect firework-related injuries. CONCLUSION: Between 1 December 2017 and 31 January 2018 in the south-west Netherlands trauma region mainly teenage males and bystanders sustained firework-related injuries. Most injuries were upper extremity burns and eye injuries, mainly due to legal fireworks and bangers or decorative fireworks. The extent of the sample indicatDoel
Een volledig overzicht geven van het aantal vuurwerkslachtoffers dat in december 2017 en januari 2018 behandeld werd in een
ziekenhuis in de traumaregio Zuidwest-Nederland, het gebruikte soort vuurwerk en de specifieke letsels.
Opzet
Een prospectieve, multicentrische cohortstudie (NTR6793).
Methode
Patiënten van alle leeftijden met vuurwerkletsel kwamen in aanmerking voor inclusie. Het letsel moest zijn ontstaan in de periode 1
december 2017-31 januari 2018 en zijn behandeld in een ziekenhuis in de traumaregio Zuidwest-Nederland (circa 2,5 miljoen
inwoners). Gegevens werden verzameld vanuit het patiëntendossier en aanvullende gegevens werden verkregen tijdens een
interview.
Resultaten
Er werden 54 patiënten geïncludeerd. Het overgrote deel betrof mannen (93%) en de mediane leeftijd was 15 jaar. 25 gewonden
(46%) waren omstander en 12 mensen (22%) raakten gewond door illegaal vuurwerk. Van de 54 patiënten raakten er 50 gewond
door knalvuurwerk (n = 22) of siervuurwerk (n = 28). De 54 geïncludeerde patiënten hadden 79 letsels; het letsel was 29 keer
(37%) gelokaliseerd aan armen of handen en 19 keer (24%) aan de ogen. Letsel aan de arm of hand bestond voornamelijk uit
brandwonden (69%), met name tweedegraads. Oogletsel werd 14 keer door stomp inwerkend geweld veroorzaakt, 7 keer door
chemisch letsel en 1 keer werd het oog gepenetreerd. Er raakten 3 patiënten indirect gewond door vuurwerk.
Conclusie
In de traumaregio Zuidwest-Nederland raakten in de 2 maanden rond de jaarwisseling 2017-2018 vooral minderjarige mannen en
omstanders gewond. Slachtoffers liepen met name brandwonden aan armen of handen of oogletsel op. De verwondingen waren met
name het gevolg van legaal knal- en siervuurwerk. Door de omvang van de steekproef lijken de studiebevindingen goed te
extrapoleren naar het gehele land
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