Selective school-based alcohol prevention programs targeting youth with personality risk factors for addiction and mental health problems have been found to reduce substance use and misuse in those with elevated personality profiles. Objectives: To report 24-month outcomes of the Teacher-Delivered Personality-Targeted Interventions for Substance Misuse Trial (Adventure trial) in which school staff were trained to provide interventions to students with 1 of 4 high-risk (HR) profiles: anxiety sensitivity, hopelessness, impulsivity, and sensation seeking and to examine the indirect herd effects of this program on the broader low-risk (LR) population of students who were not selected for intervention. Design: Cluster randomized controlled trial.

We present velocity spectra measured in three cryogenic liquid 4He steady flows: grid and wake flows in a pressurized wind tunnel capable of achieving mean velocities up to 5 m/s at temperatures above and below the superfluid transition, down to 1.7 K, and a "chunk" turbulence flow at 1.55 K, capable of sustaining mean superfluid velocities up to 1.3 m/s. Depending on the flows, the stagnation pressure probes used for anemometry are resolving from one to two decades of the inertial regime of the turbulent cascade. We do not find any evidence that the second order statistics of turbulence below the superfluid transition differ from the ones of classical turbulence, above the transition.Comment: 13 pages, 9 figure

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W e compared the results of different methods for diagnosing zygosity in a sample of 237 same-sex pairs of twins assessed at 5 and 18 months of age. Despite the twins' very young age and early stage of development, physical similarity was concordant with genotyping in 91.9% of cases at 5 months and 93.8% of cases at 18 months, for a subsample of 123 and 113 pairs, respectively. This concordance rate was obtained following a case-by-case assessment of each pair's physical similarity using a shortened version of the Zygosity Questionnaire for Young Twins (Goldsmith, 1991). Taking into account the chorionicity data available from the twins' medical files, we were able to classify correctly 96% of the pairs, an accuracy rate comparable to previously reported rates obtained with older twins. Chorionicity data is especially useful since we found that monochorionic MZ twins are more difficult than dichorionic MZ twins to diagnose by physical similarity at these young ages. The relative cost-benefit of methods based on reported physical similarity and DNA analysis is discussed in light of these results.

This article deals with ion confinement in small open-ended magnetic devices, the electron cyclotron resonance ion sources (ECRIS) that were developed for multicharged ion production. The ECRIS are basically ECR-heated plasma confinement machines with hot electrons and cold ions. The main parameters of the ion population in ECRIS plasmas are successively analyzed, temperature, collisions, losses, ionization, confinement times, charge state distribution equilibrium, followed by the analysis of the gas mixing effect, a specific technique to improve the performance as an ion source. A series of experiments is described for the systematic analysis of the phenomena related to gas mixing. It is shown that high charge state optimization by gas mixing relies on a compromise between three criteria, ion losses, mass effect, and ionization rates. The article stresses the role of some fundamental plasma parameters for the next generation of high charge state/high intensity ion sources.

For the needs of future heavy ion accelerators, electron cyclotron resonance ion sources (ECRISs) should be able to deliver higher intensities and higher charge states. The 1e mA level intensity has already been reached by room temperature ECRIS for medium charge states of light elements (O6+, Ar8+). However, such level of intensity for heavy elements (like Pb27+ for CERN/LHC and GSI) requires more powerful ECRIS with higher electron densities (up to 1013 cm−3). On the other hand, an optimized magnetic configuration system has to be used in order to obtain the suitable compromise between the electron confinement and the high flux ion losses. Before the design of the future “high intensity ECRIS,” experiments have been performed with the superconducting SERSE source both at 18 and 28 GHz. After an overview of major results recently obtained, some scaling laws will be presented. Our results show that much larger intensities and charges can be reached with ECRIS. Then, we will show how the next ECRIS generation will look like, based on the scaling laws derived in the above-mentioned experiments.

Using a sample of 767 children (403 girls, 364 boys), this study aimed to (a) identify groups with distinct trajectories of peer victimization over a 6-year period from primary school through the transition to secondary school, and (b) examine the associated personal (i.e., aggression or internalizing problems) and familial (family status, socioeconomic status, the parent-child relationship) predictors. Peer victimization was assessed via self-reports from Grades 4 through 9 (ages 10 through 15 years), aggression and internalizing problems were assessed in Grade 4 via peer nominations, and the parent-child relationship was assessed in Grade 7 (i.e., right after the transition to secondary school) via parent-reports. Growth Mixture modeling revealed 1 group (62%) who experienced little victimization in primary school and even less in secondary school, another group (31%) who was victimized in primary but not or much less in secondary school, and a third group (7%) who was chronically victimized in both school contexts. Boys were more likely than girls to follow any elevated victimization trajectory. Chronic victimization across primary and secondary school was predicted by nonintact family status and a combination of both internalizing problems and aggression compared with nonvictimized youth. In contrast, transitory victimization during primary but not in secondary school was predicted by aggression, but not internalizing problems. Support as well as conflict in the parent-child relationship also showed significant, albeit distinct associations with the different peer victimization trajectories.

The hot electrons in the plasma of an electron-cyclotron-resonance ion source are investigated by three passive diagnostics: bremsstrahlung, electron cyclotron emission, and diamagnetism. For this type of plasma the feasibility of the second diagnostic is an innovative development, as is the simultaneous use of two independent plasma diagnostics for either steady-state or transient experiments. In the steady-state experiments the bremsstrahlung and the electron cyclotron emission are interpreted by comparing the experimental spectra with simulated spectra calculated for the first time from a non-Maxwellian electron distribution. The ‘‘perpendicular temperatures’’ obtained by the two diagnostics are in good agreement. In the transient experiments the electron cyclotron emission and the diamagnetic signals are recorded to study the electron density and the electron lifetime. All these experiments performed using the Minimafios ion source working at 18 GHz with oxygen gas demonstrate trends and saturation effects when the gas injection pressure and the radio-frequency power are varied.