Production of HD Molecules in Definite Hyperfine Substates.

Polarized atomic beam sources have been in operation for many years to produce either nuclear polarized atomic hydrogen or deuterium beams. In recent experiments, such a source was used to polarize both isotopes independently at the same time. By recombination of the atoms, hydrogen-deuterium molecules with all possible nuclear spin combinations can be created. Those spin isomers are useful for further applications, like precision spectroscopy, as polarized targets for laser-particle acceleration, polarized fuel for fusion reactors, or as an option for future measurements of electric dipole moments.

Isotensor Dibaryon in the pp→ppπ

Exclusive measurements of the quasifree pp→ppπ^{+}π^{-} reaction have been carried out at WASA@COSY by means of pd collisions at T_{p}=1.2 GeV. Total and differential cross sections have been extracted covering the energy region T_{p}=1.08-1.36 GeV, which is the region of N^{*}(1440) and Δ(1232)Δ(1232) resonance excitations. Calculations describing these excitations by t-channel meson exchange are at variance with the measured differential cross sections and underpredict substantially the experimental total cross section. An isotensor ΔN dibaryon resonance with I(J^{P})=2(1^{+}) produced associatedly with a pion is able to overcome these deficiencies.

Spin Dependence of η Meson Production in Proton-Proton Collisions Close to Threshold.

Taking advantage of the high acceptance and axial symmetry of the WASA-at-COSY detector, and the high polarization degree of the proton beam of COSY, the reaction p[over →]p→ppη has been measured close to threshold to explore the analyzing power A_{y}. The angular distribution of A_{y} is determined with the precision improved by more than 1 order of magnitude with respect to previous results, allowing a first accurate comparison with theoretical predictions. The determined analyzing power is consistent with zero for an excess energy of Q=15 MeV, signaling s-wave production with no evidence for higher partial waves. At Q=72 MeV the data reveal strong interference of Ps and Pp partial waves and cancellation of (Pp)^{2} and Ss^{*}Sd contributions. These results rule out the presently available theoretical predictions for the production mechanism of the η meson.

Attentional bias in problematic drinkers with and without mild to borderline intellectual disability.

BACKGROUND: Problematic drinkers favour the processing of alcohol-related stimuli at the cost of other stimuli and also find it difficult to disengage their attention from these stimuli. This is indicative of an attentional bias towards alcohol. The goal of this study was to examine this bias in problematic drinkers with and without mild to borderline intellectual disability (MBID) using both eye tracking methodology and behavioural data (i.e. reaction time (RT) data). METHOD: Participants (N = 133) were divided into four groups based on (estimated) full scale intelligence quotient (IQ) and severity of alcohol use-related problems. The severity of substance use-related problems was assessed with the Alcohol Use Disorder Identification Test (AUDIT). The visual dot probe task was used to measure the attentional bias. We analysed both eye tracking data and behavioural data (i.e. RT data) of the visual dot probe task. RESULTS: Problematic drinkers were not more likely than light drinkers to direct their attention towards pictures of alcoholic beverages, did not look at these pictures longer than light drinkers and did also not respond faster than light drinkers to probes replacing pictures of alcoholic beverages. However, the strength of the attentional bias varied profusely. CONCLUSION: Taking the large variability in the strength of the attentional bias and the poor psychometric qualities of the measures into consideration, it is concluded that the use of these measures for clinical purposes is discouraged.

[Online self-help for persons with suicidal intentions: budget impact analysis]. / Onlinehulp bij suïcidale gedachten: budgetimpactanalyse.

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How to Reach a Thousand-Second in-Plane Polarization Lifetime with 0.97-GeV/c Deuterons in a Storage Ring.

We observe a deuteron beam polarization lifetime near 1000 s in the horizontal plane of a magnetic storage ring (COSY). This long spin coherence time is maintained through a combination of beam bunching, electron cooling, sextupole field corrections, and the suppression of collective effects through beam current limits. This record lifetime is required for a storage ring search for an intrinsic electric dipole moment on the deuteron at a statistical sensitivity level approaching 10^{-29} e cm.

Home-based alcohol prevention program for parents and children: A randomized controlled trial.

Objective To evaluate the effectiveness of a home-based alcohol prevention program to delay initiation of alcohol use in children. Methods In 2011, a total of 1349 sixth-grade children (M=12.15, SD=0.47) and their mothers who could read and write Dutch were recruited from primary schools in the northern part of the Netherlands. They participated in a cluster randomized controlled trial with two conditions; (1) intervention group (5 modules which families received by mail every 4weeks over 5months), (2) control group (a factsheet information brochure). An independent statistician allocated the schools to the conditions (allocation ratio (1:1)). Participants and data-analyst were blind to randomization. The primary outcome was alcohol initiation. Results Of the participants, 680 were randomized to the intervention and 669 to the control condition. In the intervention condition (N=540) 5.4% of the children drank alcohol compared to 7.1% in the control condition (N=601). The difference was not significant (OR=.99, 95% CI=.96-1.02, p=52). Conclusion The present study showed no effects of 'In control: No alcohol!' on alcohol initiation. A critical evaluation of program design and content, and future studies in different target groups, are suggested. The trial is registered at trialregister.nl, number NTR2474.

Adolescent Loneliness and Social Skills: Agreement and Discrepancies Between Self-, Meta-, and Peer-Evaluations.

Lonely adolescents report that they have poor social skills, but it is unknown whether this is due to an accurate perception of a social skills deficit, or a biased negative perception. This is an important distinction, as actual social skills deficits require different treatments than biased negative perceptions. In this study, we compared self-reported social skills evaluations with peer-reported social skills and meta-evaluations of social skills (i.e., adolescents' perceptions of how they believe their classmates evaluate them). Based on the social skills view, we expected negative relations between loneliness and these three forms of social skills evaluations. Based on the bias view, we expected lonely adolescents to have more negative self- and meta-evaluations compared to peer-evaluations of social skills. Participants were 1342 adolescents (48.64 % male, M age = 13.95, SD = .54). All classmates rated each other in a round-robin design to obtain peer-evaluations. Self- and meta-evaluations were obtained using self-reports. Data were analyzed using polynomial regression analyses and response surface modeling. The results indicated that, when self-, peer- and meta-evaluations were similar, a greater sense of loneliness was related to poorer social skills. Loneliness was also related to larger discrepancies between self- and peer-evaluations of loneliness, but not related to the direction of these discrepancies. Thus, for some lonely adolescents, loneliness may be related to an actual social skills deficit, whereas for others a biased negative perception of one's own social skills or a mismatch with the environment may be related to their loneliness. This implies that different mechanisms may underlie loneliness, which has implications for interventions.

Substance use prevention program for adolescents with intellectual disabilities on special education schools: a cluster randomised control trial.

BACKGROUND: Students without intellectual disability (ID) start experimenting with tobacco and alcohol between 12 and 15 years of age. However, data for 12- to 15-year old students with ID are unavailable. Prevention programs, like 'PREPARED ON TIME' (based on the attitude-social influence-efficacy model), are successful, but their efficacy has not been studied in students with ID. The objectives of this study were (1) to undertake a cluster randomised control trial to test the efficacy of the e-learning program among 12- to 15-year old students with mild and borderline ID in secondary special-needs schools and (2) to examine the tobacco and alcohol use for this population. METHODS: Five schools, randomly selected to be part of either the experimental group or the control group, participated in this study. Passive informed consent was used in which parents and their children can refuse to participate in the study, resulting in 111 students in the experimental group and 143 students in the control group. A total of 210 students completed both baseline and follow-up questionnaires. Primary outcome variables are the knowledge and attitude towards alcohol and tobacco use. This study is registered in the ISRCTN registry with number ISRCTN95279686. RESULTS: Baseline findings showed that a large proportion of all respondents had initiated smoking (49%) and drinking (75%), well above the expected numbers based on national figures. 'PREPARED ON TIME' did not affect the behavioural determinants (i.e. attitude, subjective norm and self-efficacy), except modelling on smoking. Additionally, alcohol-related knowledge of students in the experimental group increased after the completion of the program. CONCLUSIONS: To obtain effective results on behavioural outcomes from 'PREPARED ON TIME', a greater degree of flexibility (i.e. repetition, extension of the program, role playing, etc.) is required. Furthermore, prevention needs to be implemented at a younger age, as 6% of the students tried their first cigarette and 15% of the students drank alcohol at the age of 10 years or younger.

The addicted brain: cognitive biases in problematic drinkers with mild to borderline intellectual disability.

BACKGROUND: Substance use disorders (SUD) are associated with several neurobiological disruptions, including biases in attention and approach/avoidance behaviour. The aims of this study were to compare the strength of cognitive biases between light and problematic drinkers, to explore the role of IQ on the cognitive biases and to study the psychometric qualities of the measures. METHOD: Participants (N = 130) were divided into four groups based on IQ and severity of alcohol use-related problems: light (n = 28) and problematic drinkers (n = 25) with (sub)average IQ and light (n = 33) and problematic drinkers (n = 44) with mild to borderline intellectual disability (MBID). All participants performed the visual dot probe task and the approach avoidance task to measure the strength of cognitive biases. RESULTS: In contrast with the hypothesis, no cognitive biases were found in problematic drinkers. Full scale IQ nor level of craving influenced the strength of the cognitive biases in light and problematic drinkers, although IQ did influence task performance (i.e. large intra-individual, trial-to-trial variation in reaction time). The internal consistency of the visual dot probe task was good, whereas the internal consistency of the approach avoidance task was poor. CONCLUSION: Cognitive biases seem to vary within the group of problematic drinkers as a whole. The psychometric qualities of the measures are problematic, especially in relation to the intra-individual variability in reaction time found in participants with MBID. Until the implications of this variability on the validity of implicit measures and establishing bias scores are more clear, the use of these measures in individuals with MBID calls for scrutiny.

New Method for a Continuous Determination of the Spin Tune in Storage Rings and Implications for Precision Experiments.

A new method to determine the spin tune is described and tested. In an ideal planar magnetic ring, the spin tune-defined as the number of spin precessions per turn-is given by ν(s)=γG (γ is the Lorentz factor, G the gyromagnetic anomaly). At 970 MeV/c, the deuteron spins coherently precess at a frequency of ≈120 kHz in the Cooler Synchrotron COSY. The spin tune is deduced from the up-down asymmetry of deuteron-carbon scattering. In a time interval of 2.6 s, the spin tune was determined with a precision of the order 10^{-8}, and to 1×10^{-10} for a continuous 100 s accelerator cycle. This renders the presented method a new precision tool for accelerator physics; controlling the spin motion of particles to high precision is mandatory, in particular, for the measurement of electric dipole moments of charged particles in a storage ring.

Production of hyperpolarized H_{2} molecules from H[over →] atoms in gas-storage cells.

The preservation of the nuclear polarization of hydrogen atoms during the recombination to molecules was observed on different surface materials in the temperature range from 45 to 100 K and for magnetic fields up to 1 T. On a gold and a fused quartz surface, the expected molecular polarization of about 50% or lower of the atomic polarization was measured, while a surface layer of perfluoropolyether (Fomblin) shows a nearly complete preservation (at least 97%) of the atomic polarization during the recombination process. Further experiments have the possibility of storing polarized deuterium molecules and to use them in nuclear-fusion installations. Another application might be the production of polarized substances for enhanced NMR techniques.

The Effectiveness of Family Interventions in Preventing Adolescent Illicit Drug Use: A Systematic Review and Meta-analysis of Randomized Controlled Trials.

In order to quantify the effectiveness of family interventions in preventing and reducing adolescent illicit drug use, we conducted a systematic review and meta-analysis of randomized controlled trials. We searched the Cochrane Database of Systematic Reviews, Educational Research Information Centre (ERIC), MEDLINE, Embase, and PsycINFO for studies published between 1995 and 2013. Results were described separately for different outcomes (marijuana vs. other illicit drugs) and intervention types (universal, selective, and indicated prevention). Meta-analyses were performed when data were sufficient (e.g., marijuana and other illicit drug initiation in universal samples), using random effect models. Otherwise, we provided narrative reviews (e.g., regarding selective and indicated prevention). Thirty-nine papers describing 22 RCTs were eligible for inclusion. Universal family interventions targeting parent-child dyads are likely to be effective in preventing (OR 0.72; 95 % CI 0.56, 0.94) and reducing adolescent marijuana use, but not in preventing other illicit drugs (OR 0.90; 95 % CI 0.60, 1.34). Among high-risk groups, there is no clear evidence for the effectiveness of family interventions in preventing and reducing illicit drug use and drug disorders. The three small RCTs among substance-(ab)using adolescents gave some indication that programs might reduce the frequency of illicit drug use. Family interventions targeting parent-child dyads are likely to be effective in preventing and reducing adolescent marijuana use in general populations, but no evidence for other illicit drug use was found. We underline the need to strengthen the evidence base with more trials, especially among at-risk populations.

The role of general parenting and cannabis-specific parenting practices in adolescent cannabis and other illicit drug use.

AIMS: To investigate general and cannabis-specific parenting practices in relation to adolescent cannabis and other illicit drug use. METHODS: Data were derived from the Dutch National School Survey on Substance Use among students (N=3209; aged 12-16 years) and one of their parents in 2011. RESULTS: Logistic regression analyses revealed that 1) parental cannabis use was significantly related to more adolescent lifetime and recent cannabis use, and 2) restrictive cannabis-specific parental rules were associated with less adolescent recent cannabis and lifetime use of other illicit drugs, even when controlled for sociodemographic factors, general parenting, adolescent tobacco use, and tobacco-specific parenting. In addition, no significant interaction was observed between parental cannabis use and cannabis-specific rules in their relation to adolescent cannabis and other illicit drug use, indicating that cannabis rules are evenly associated with adolescent drug use for families with and without parental cannabis experience. CONCLUSIONS: In addition to general parenting practices, restrictive cannabis-specific rules are related to lower adolescent cannabis and other illicit drug rates. Parents who ever used cannabis have children with a higher prevalence of cannabis use. However, their restrictive cannabis-specific rules are equally related to a lower chance of adolescent cannabis use.

[Dopamine and excessive alcohol consumption: how genes interact with their environment]. / Dopamine en overmatig alcoholgebruik: genen in interactie met hun omgeving.

BACKGROUND: Hereditary factors account for approximately 50% of the risk of developing alcohol dependence. Genes that affect the dopamine function in the brain have been extensively studied as candidate genes. AIM: To present the results of recent Dutch studies on the interaction between genes and their environment in relation to dopamine function and excessive alcohol use. METHOD: Two large scale research projects were recently carried out in order to study the relation between dopamine genes and excessive alcohol use in the Netherlands. The first study investigated excessive alcohol use among adolescents. The second studied alcohol dependence among adult males. RESULTS: Genes that affect the dopamine function in the brain were not directly linked to excessive alcohol use or dependence. Dopamine genes, however, do influence sensitivity to environmental risk factors for excessive alcohol use. CONCLUSION: These studies show that genetically determined dopamine function increases the risk of excessive alcohol use in the context of an adverse environment. Traumatic experiences and parenting style were both shown to be important environmental factors.

The effect of an intervention on schoolchildren's susceptibility to a peer's candy intake.

BACKGROUND/OBJECTIVES: The aim of the study was to pilot test two interventions designed to reduce children's susceptibility to peers' candy intake and to determine if interventions had different effects on boys and girls. SUBJECTS/METHODS: In the standard intervention, peer modeling was explained while communicating the importance of not following other's food intake by means of photos, video clips and interactive tasks. A second animated intervention was similar but added a monkey puppet as a (cue) reminder. A social modeling component was conducted 1 day after the intervention to test whether the interventions affected the extent to which children model their peers' eating. During the modeling session, the participants' (N = 141; 78% boys, mean age = 7.84 ± 0.72 years) solved a puzzle with a same-sex 'confederate' who was instructed to eat chocolate candy when he/she was covertly signaled. The monkey puppet was put in sight to test whether the monkey served as a cue reminder in the animated intervention. Candy intake was compared across control and intervention conditions. RESULTS: The standard intervention reduced candy intake in boys but not girls. Nevertheless, children still remained susceptible to a peer's eating. There was no significant effect of the animated intervention on consumption. CONCLUSIONS: There are gender differences when children are exposed to an (over)eating peer. Although interventions are effective, social norms can be powerful. Social networks should be leveraged when possible.

Abashian-Booth-Crowe effect in basic double-pionic fusion: a new resonance?

We report on an exclusive and kinematically complete high-statistics measurement of the basic double-pionic fusion reaction pn→dπ(0)π(0) over the full energy region of the ABC effect, a pronounced low-mass enhancement in the ππ-invariant mass spectrum. The measurements, which cover also the transition region to the conventional t-channel ΔΔ process, were performed with the upgraded WASA detector setup at COSY. The data reveal the Abashian-Booth-Crowe effect to be uniquely correlated with a Lorentzian energy dependence in the integral cross section. The observables are consistent with a narrow resonance with m=2.37 GeV, Γ≈70 MeV and I(J(P))=0(3(+)) in both pn and ΔΔ systems. Necessary further tests of the resonance interpretation are discussed.

[Positive life events and mood disorders: longitudinal evidence for a chaotic life-course hypothesis]. / Positieve levensgebeurtenissen en stemmingsstoornissen: longitudinaal bewijs voor een chaotische-levensloophypothese.

BACKGROUND: In psychiatric research it is often assumed that detrimental effects of negative life events on mental health can be buffered by a number of positive life events. However, there is no convincing empirical evidence that this assumption is correct; it can even be argued that positive life events act as additional stressors rather than as buffers, leading to a continuation of a chaotic life course and an increase in the risk of affective disorders. AIM: To find out whether positive life events were associated with a higher risk of the occurrence of mood disorders and whether such an association could be explained by a number of negative life events that individuals had experienced. METHOD: We used data from 4,796 adults, aged 18-64, collected at two measurement moments (i.e. 1997 and 1999) of NEMESIS, a Dutch prospective-epidemiological study. As a basis for our measurements we used dsm-iii-r diagnoses of major depressive disorders and dysthymia and the Life Events and Difficulties Schedules LEDS. RESULTS: A multivariate (MPlus) path analysis demonstrated that positive life events were not, in themselves, significantly predictive of affective disorders. Positive life events were only related to the risk of mood disorders when they co-occurred with a high number of negative life events. CONCLUSIONS: In accordance with a chaotic life-course hypothesis, positive events were not found to buffer the detrimental impact of negative life events, but when they are part of an erratic course of life they can pose an extra threat to an individual's mental health.

Do smooth waters run deep? Alcohol intoxication and the effects of water consumption on driving-related cognitions and behavior.

The present study tested the effect of the combined use of alcohol and water on driving-related cognitions and behavior. Seventy-four female students performed a driving simulator task after having consumed alcohol or a placebo. Additionally, half of the participants consumed 0.5 liter of water. It was hypothesized that combining alcohol and water could lead to an underestimated perceived intoxication level resulting in more favorable driving cognitions and increased risk behavior. Our findings showed that the combined use of water and alcohol did not affect cognitions or behavior. Surprisingly, in the placebo condition, water intake increased risky driving cognitions and behavior in women with a history of accident involvement. Lacking a clear counterproductive effect when combined with alcohol, water could be a useful tool in limiting alcohol use among female drinkers.