162 research outputs found
Search for Correlated High Energy Cosmic Ray Events with CHICOS
We present the results of a search for time correlations in high energy
cosmic ray data (primary E > 10^14 eV) collected by the California HIgh school
Cosmic ray ObServatory (CHICOS) array. Data from 69 detector sites spread over
an area of 400 km^2 were studied for evidence of isolated events separated by
more than 1 km with coincidence times ranging from 1 microseconds up to 1
second. We report upper limits for the coincidence probability as a function of
coincidence time.Comment: 4 pages, 4 figures, Proceedings of 29th International Cosmic Ray
Conference (ICRC) 2005, Pune, Indi
Spallation reactions. A successful interplay between modeling and applications
The spallation reactions are a type of nuclear reaction which occur in space
by interaction of the cosmic rays with interstellar bodies. The first
spallation reactions induced with an accelerator took place in 1947 at the
Berkeley cyclotron (University of California) with 200 MeV deuterons and 400
MeV alpha beams. They highlighted the multiple emission of neutrons and charged
particles and the production of a large number of residual nuclei far different
from the target nuclei. The same year R. Serber describes the reaction in two
steps: a first and fast one with high-energy particle emission leading to an
excited remnant nucleus, and a second one, much slower, the de-excitation of
the remnant. In 2010 IAEA organized a worskhop to present the results of the
most widely used spallation codes within a benchmark of spallation models. If
one of the goals was to understand the deficiencies, if any, in each code, one
remarkable outcome points out the overall high-quality level of some models and
so the great improvements achieved since Serber. Particle transport codes can
then rely on such spallation models to treat the reactions between a light
particle and an atomic nucleus with energies spanning from few tens of MeV up
to some GeV. An overview of the spallation reactions modeling is presented in
order to point out the incomparable contribution of models based on basic
physics to numerous applications where such reactions occur. Validations or
benchmarks, which are necessary steps in the improvement process, are also
addressed, as well as the potential future domains of development. Spallation
reactions modeling is a representative case of continuous studies aiming at
understanding a reaction mechanism and which end up in a powerful tool.Comment: 59 pages, 54 figures, Revie
Prevalence of childhood stress and associated factors: a study of schoolchildren in a city in Rio Grande do Sul State, Brazil
Psychological determinants of financial buffer saving: the influence of financial risk tolerance and regulatory focus
Heat or Insulation: Behavioral Titration of Mouse Preference for Warmth or Access to a Nest
In laboratories, mice are housed at 20–24°C, which is below their lower critical temperature (≈30°C). This increased thermal stress has the potential to alter scientific outcomes. Nesting material should allow for improved behavioral thermoregulation and thus alleviate this thermal stress. Nesting behavior should change with temperature and material, and the choice between nesting or thermotaxis (movement in response to temperature) should also depend on the balance of these factors, such that mice titrate nesting material against temperature. Naïve CD-1, BALB/c, and C57BL/6 mice (36 male and 36 female/strain in groups of 3) were housed in a set of 2 connected cages, each maintained at a different temperature using a water bath. One cage in each set was 20°C (Nesting cage; NC) while the other was one of 6 temperatures (Temperature cage; TC: 20, 23, 26, 29, 32, or 35°C). The NC contained one of 6 nesting provisions (0, 2, 4, 6, 8, or 10g), changed daily. Food intake and nest scores were measured in both cages. As the difference in temperature between paired cages increased, feed consumption in NC increased. Nesting provision altered differences in nest scores between the 2 paired temperatures. Nest scores in NC increased with increasing provision. In addition, temperature pairings altered the difference in nest scores with the smallest difference between locations at 26°C and 29°C. Mice transferred material from NC to TC but the likelihood of transfer decreased with increasing provision. Overall, mice of different strains and sexes prefer temperatures between 26–29°C and the shift from thermotaxis to nest building is seen between 6 and 10 g of material. Our results suggest that under normal laboratory temperatures, mice should be provided with no less than 6 grams of nesting material, but up to 10 grams may be needed to alleviate thermal distress under typical temperatures
Constraints on Energy Intake in Fish: The Link between Diet Composition, Energy Metabolism, and Energy Intake in Rainbow Trout
The hypothesis was tested that fish fed to satiation with iso-energetic diets differing in macronutrient composition will have different digestible energy intakes (DEI) but similar total heat production. Four iso-energetic diets (2×2 factorial design) were formulated having a contrast in i) the ratio of protein to energy (P/E): high (HP/E) vs. low (LP/E) and ii) the type of non-protein energy (NPE) source: fat vs. carbohydrate which were iso-energetically exchanged. Triplicate groups (35 fish/tank) of rainbow trout were hand-fed each diet twice daily to satiation for 6 weeks under non-limiting water oxygen conditions. Feed intake (FI), DEI (kJ kg−0.8 d−1) and growth (g kg−0.8 d−1) of trout were affected by the interaction between P/E ratio and NPE source of the diet (P<0.05). Regardless of dietary P/E ratio, the inclusion of carbohydrate compared to fat as main NPE source reduced DEI and growth of trout by ∼20%. The diet-induced differences in FI and DEI show that trout did not compensate for the dietary differences in digestible energy or digestible protein contents. Further, changes in body fat store and plasma glucose did not seem to exert a homeostatic feedback control on DEI. Independent of the diet composition, heat production of trout did not differ (P>0.05). Our data suggest that the control of DEI in trout might be a function of heat production, which in turn might reflect a physiological limit related with oxidative metabolism
Has Motivational Interviewing fallen into its own Premature Focus Trap?
Since the initial conception of the behaviour change method Motivational Interviewing, there has been a shift evident in epistemological, methodological and practical applications, from an inductive, process and practitioner-focussed approach to that which is more deductive, research-outcome, and confirmatory-focussed. This paper highlights the conceptual and practical problems of adopting this approach, including the consequences of assessing the what (deductive outcome-focussed) at the expense of the how (inductively process-focussed). We encourage a return to an inductive, practitioner and client-focussed MI approach and propose the use of Computer Assisted Qualitative Data Analysis Systems such as NVivo in research initiatives to support this aim
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