A Bayesian approach to evaluate confidence intervals in counting experiments with background

In this paper we propose a procedure to evaluate Bayesian confidence intervals in counting experiments where both signal and background fluctuations are described by the Poisson statistics. The results obtained when the method is applied to the calculation of upper limits will also be illustrated.Comment: 19 pages, 6 figure

Carnivory in Adult Female Eumenid Wasps (Hymenoptera: Vespidae: Eumeninae) and Its Effect on Egg Production

Seventy captive adult female wasps of the eumenid genera Ancistrocerus and Euodynerus were observed to feed on multiple prey items. It was shown experimentally that E. foraminatus females that fed on prey had significantly larger egg volumes than adult wasps deprived of prey

Methods for Artificial Rearing of Solitary Eumenid Wasps (Hymenoptera: Vespidae: Eumeninae)

Solitary eumenid wasps of the genera Ancistrocerus and Euodynerus can be reared in small cages. Laboratory-reared larvae of the spruce budworm caterpillars, Choristoneura fumiferana (Lepidoptera: Torlricidae) are suitable prey

Charm Meson Mixing: An Experimental Review

We review current experimental results on charm mixing and CP violation. We survey experimental techniques, including time-dependent, time-independent, and quantum-correlated measurements. We review techniques that use a slow pion tag from D*+ --> pi+ D0 + c.c. decays and those that do not, and cover two-body and multi-body D0 decay modes. We provide a summary of D-mixing results to date and comment on future experimental prospects at the LHC and other new or planned facilities.Comment: 53 pages, 29 figures, 8 table

Variable camber rotor study

Deployment of variable camber concepts on helicopter rotors was analytically assessed. It was determined that variable camber extended the operating range of helicopters provided that the correct compromise can be obtained between performance/loads gains and mechanical complexity. A number of variable camber concepts were reviewed on a two dimensional basis to determine the usefulness of leading edge, trailing edge and overall camber variation schemes. The most powerful method to vary camber was through the trailing edge flaps undergoing relatively small motions (-5 deg to +15 deg). The aerodynamic characteristics of the NASA/Ames A-1 airfoil with 35% and 50% plain trailing edge flaps were determined by means of current subcritical and transonic airfoil design methods and used by rotor performance and loads analysis codes. The most promising variable camber schedule reviewed was a configuration with a 35% plain flap deployment in an on/off mode near the tip of a blade. Preliminary results show approximately 11% reduction in power is possible at 192 knots and a rotor thrust coefficient of 0.09. The potential demonstrated indicates a significant potential for expanding the operating envelope of the helicopter. Further investigation into improving the power saving and defining the improvement in the operational envelope of the helicopter is recommended

A comparison between detailed and configuration-averaged collisional-radiative codes applied to non-local thermal equilibrium plasma

A collisional-radiative model describing nonlocal-thermodynamic-equilibrium plasmas is developed. It is based on the HULLAC (Hebrew University Lawrence Livermore Atomic Code) suite for the transitions rates, in the zero-temperature radiation field hypothesis. Two variants of the model are presented: the first one is configuration averaged, while the second one is a detailed level version. Comparisons are made between them in the case of a carbon plasma; they show that the configuration-averaged code gives correct results for an electronic temperature Te=10 eV (or higher) but fails at lower temperatures such as Te=1 eV. The validity of the configuration-averaged approximation is discussed: the intuitive criterion requiring that the average configuration-energy dispersion must be less than the electron thermal energy turns out to be a necessary but far from sufficient condition. Another condition based on the resolution of a modified rate-equation system is proposed. Its efficiency is emphasized in the case of low-temperature plasmas. Finally, it is shown that near-threshold autoionization cascade processes may induce a severe failure of the configuration-average formalism.Comment: 9

Nucleosynthesis Modes in the High-Entropy-Wind of Type II Supernovae: Comparison of Calculations with Halo-Star Observations

While the high-entropy wind (HEW) of Type II supernovae remains one of the more promising sites for the rapid neutron-capture (r-) process, hydrodynamic simulations have yet to reproduce the astrophysical conditions under which the latter occurs. We have performed large-scale network calculations within an extended parameter range of the HEW, seeking to identify or to constrain the necessary conditions for a full reproduction of all r-process residuals N_{r,\odot}=N_{\odot}-N_{s,\odot} by comparing the results with recent astronomical observations. A superposition of weighted entropy trajectories results in an excellent reproduction of the overall N_{r,\odot}-pattern beyond Sn. For the lighter elements, from the Fe-group via Sr-Y-Zr to Ag, our HEW calculations indicate a transition from the need for clearly different sources (conditions/sites) to a possible co-production with r-process elements, provided that a range of entropies are contributing. This explains recent halo-star observations of a clear non-correlation of Zn and Ge and a weak correlation of Sr - Zr with heavier r-process elements. Moreover, new observational data on Ru and Pd seem to confirm also a partial correlation with Sr as well as the main r-process elements (e.g. Eu).Comment: 15 pages, 1 table, 4 figures; To be published in the Astrophysical Journal Letter

Difference in prevalence of common mental disorder as measured using four questionnaire delivery methods among young people in rural Zimbabwe.

BACKGROUND: Previous studies have suggested that interviewer-administered questionnaires can under-estimate the prevalence of depression and suicidal ideation when compared with self-administered ones. We report here on differences in prevalence of reporting mental health between four questionnaire delivery modes (QDM). METHODS: Mental health was assessed using the Shona Symptom Questionnaire (SSQ), a locally validated 14-item indigenous measure for common mental affective disorders. A representative sample of 1495 rural Zimbabwean adolescents (median age 18) was randomly allocated to one of four questionnaire delivery modes: self-administered questionnaire (SAQ), SAQ with audio (AASI), interviewer-administered questionnaire (IAQ), and audio computer-assisted survey instrument (ACASI). RESULTS: Prevalence of common affective disorders varied between QDM (52.3%, 48.6%, 41.5%, and 63.6% for SAQ, AASI, IAQ, and ACASI respectively (P<0.001)). Fewer participants failed to complete SSQ using IAQ and ACASI than other methods (1.6% vs. 12.3%; P<0.001). Qualitative data suggested that respondents found it difficult answering questions honestly in front of an interviewer. LIMITATIONS: Direction of accuracy cannot be ascertained due to lack of objective or clinical assessments of affective disorders. CONCLUSIONS: Estimates of prevalence of psychosomatic symptoms and suicidal ideation varied according to mode of interview. As each mode's direction of accuracy remains unresolved evaluations of interventions continue to be hampered