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Background: Low IQ is a risk factor for psychosis, but the effect of high IQ is more controversial. The aim was to explore the association of childhood school success with prodromal symptoms in adolescence and psychoses in adulthood. Methods: In the general population-based Northern Finland Birth Cohort 1986 (n = 8 229), we studied the relationship between teacher-assessed learning deficits, special talents and general school success at age 8 years and both prodromal symptoms (PROD-screen) at age 15–16 years and the occurrence of psychoses by age 30 years. Results: More prodromal symptoms were experienced by those talented in oral presentation [boys: adjusted odds ratio (OR) 1.49; 95% confidence interval 1.14–1.96; girls: 1.23; 1.00–1.52] or drawing (boys: 1.44; 1.10–1.87). Conversely, being talented in athletics decreased the probability of psychotic-like symptoms (boys: OR 0.72; 0.58–0.90). School success below average predicted less prodromal symptoms with boys (OR 0.68; 0.48–0.97), whereas above-average success predicted more prodromal symptoms with girls (OR 1.22; 1.03–1.44). The occurrence of psychoses was not affected. Learning deficits did not associate with prodromal symptoms or psychoses. Conclusions: Learning deficits in childhood did not increase the risk of prodromal symptoms in adolescence or later psychosis in this large birth cohort. Learning deficits are not always associated with increased risk of psychosis, which might be due to, e.g. special support given in schools. The higher prevalence of prodromal symptoms in talented children may reflect a different kind of relationship of school success with prodromal symptoms compared to full psychoses. [ABSTRACT FROM AUTHOR]

Plasma assisted combustion is a very active research field due to the potential of using the technology to improve combustion efficiency and decrease pollutant emission by stabilizing lean burning flames. It has been shown in a number of studies that a small amount of electrical energy can be deposited in the flame by applying microwaves, resulting in enhanced flame propagation and thus improved flame stabilization and delayed lean blow-out. However, the effects have not yet been properly quantified since there are significant experimental challenges related to the determination of both the laminar burning velocity and the electric field strength. In the present work, a novel setup is described, where a well-defined burner system is coupled to a microwave cavity. The burner is of heat flux type, where a flat laminar flame is stabilized on a perforated burner head. The advantage of this burner for the current use is that the method and related uncertainties are well studied and quantified, and the geometry is suitable for coupling with the microwave cavity. The setup, experimental procedure, and data analysis are described in detail in this article. Laminar burning velocity for a methane-air flame at ϕ = 0.7 is determined to certify that the burner works properly in the microwave cavity. The flame is then exposed to pulsed microwaves at 1 kHz with a pulse duration of 50 µs. The laminar burning velocity at these conditions is determined to be 18.4 cm/s, which is an increase by about 12% compared to the laminar burning velocity that is measured without microwave exposure. The setup shows potential for further investigations of lean flames subjected to various microwave pulse sequences. The data are of high quality with well-defined uncertainties and are therefore suitable to use for validation of chemical kinetics models. [ABSTRACT FROM AUTHOR]

Background: Psychiatric disorders tend to be developmental, and longitudinal settings are required to examine predictors of psychiatric phenomena. Replicating and combining data and results from different birth cohorts, which are a source of reliable data, can make research even more valuable. The Finnish Psychiatric Birth Cohort Consortium (PSYCOHORTS) project combines birth cohorts in Finland. Aim: The aim of this paper is to introduce content, plans and perspectives of the PSYCOHORTS project that brings together researchers from Finland. In addition, we illustrate an example of data harmonization using available data on causes of death. Content: PSYCOHORTS includes eight Finnish birth cohorts. The project has several plans: to harmonize different data from birth cohorts, to incorporate biobanks into psychiatric birth cohort research, to apply multigenerational perspectives, to integrate longitudinal patterns of marginalization and inequality in mental health, and to utilize data in health economics research. Data on causes of death, originally obtained from Finnish Cause of Death register, were harmonized across the six birth cohorts using SAS macro facility. Results: Harmonization of the cause of death data resulted in a total of 21,993 observations from 1965 to 2015. For example, the percentage of deaths due to suicide and the sequelae of intentional self-harm was 14% and alcohol-related diseases, including accidental poisoning by alcohol, was 13%. Conclusions: PSYCOHORTS lays the foundation for complex examinations of psychiatric disorders that is based on compatible datasets, use of biobanks and multigenerational approach to risk factors, and extensive data on marginalization and inequality. [ABSTRACT FROM AUTHOR]

Irradiating a flame by microwave radiation is one of several plasma-assisted combustion (PAC) technologies that can be used to modify the combustion chemical kinetics in order to improve flame-stability and to delay lean blow-out. One practical implication is that engines may be able to operate with leaner fuel mixtures and have an improved fuel flexibility capability including biofuels. In addition, this technology may assist in reducing thermoacoustic instabilities that may severely damage the engine and increase emission production. To examine microwave-assisted combustion a combined experimental and computational study of microwave-assisted combustion is performed for a lean, turbulent, swirl-stabilized, stratified flame at atmospheric conditions. The objectives are to demonstrate that the technology increases both the laminar and turbulent flame speeds, and modifies the chemical kinetics, enhancing the flame-stability at lean mixtures. The study combines experimental investigations using hydroxyl (OH) and formaldehyde (CH 2 O) Planar Laser-Induced Fluorescence (PLIF) and numerical simulations using finite rate chemistry Large Eddy Simulations (LES). The reaction mechanism is based on a methane (CH 4 )–air skeletal mechanism expanded with sub-mechanisms for ozone, singlet oxygen, chemionization, electron impact dissociation, ionization and attachment. The experimental and computational results show similar trends, and are used to demonstrate and explain some significant aspects of microwave-enhanced combustion. Both simulation and experimental studies are performed close to lean blow off conditions. In the simulations, the flame is gradually subjected to increasing reduced electric field strengths, resulting in a wider flame that stabilizes nearer to the burner nozzle. Experiments are performed at two equivalence ratios, where the leaner case absorbs up to more than 5% of the total flame power. Data from experiments reveal trends similar to simulated results with increased microwave absorption. [ABSTRACT FROM AUTHOR]

In plasma-assisted combustion, electric energy is added to the flame where the electric energy will be transferred to kinetic energy of the free electrons that, in turn, will modify the combustion chemical kinetics. In order to increase the understanding of this complex process, the influence of one of the products of the altered chemical kinetics, ozone (O 3 ), has been isolated and studied. This paper reports on studies using a low-swirl methane (CH 4 ) air flame at lean conditions with different concentrations of O 3 enrichment. The experimental flame diagnostics include Planar Laser Induced Fluorescence (PLIF) imaging of hydroxyl (OH) and formaldehyde (CH 2 O). The experiments are also modeled using Large Eddy Simulations (LES) with a reaction model based on a skeletal CH 4 -air reaction mechanism combined with an O 3 sub-mechanism to include the presence of O 3 in the flame. This reaction mechanism is based on fundamental considerations including reactions between O 3 and all other species involved. The experiments reveal an increase in CH 2 O in the low-swirl flame as small amounts of O 3 is supplied to the CH 4 -air stream upstream of the flame. This increase is well predicted by the LES computations and the relative radical concentration shift is in good agreement with experimental data. Simulations also reveal that the O 3 enrichment increase the laminar flame speed, s u , with ∼10% and the extinction strain-rate, σ ext , with ∼20%, for 0.57% (by volume) O 3 . The increase in σ ext enables the O 3 seeded flame to burn under more turbulent conditions than would be possible without O 3 enrichment. Sensitivity analysis indicates that the increase in σ ext due to O 3 enrichment is primarily due to the accelerated chain-branching reactions H 2 + O ⇔ OH + H , H 2 O + O ⇔ OH + OH and H + O 2 ⇔ OH + O . Furthermore, the increase in CH 2 O observed in both experiments and simulations suggest a significant acceleration of the chain-propagation reaction CH 3 + O ⇔ CH 2 O + H . [ABSTRACT FROM AUTHOR]

Accessible summary A participatory action research study on the development of a professional practice model of mental health promotion in a comprehensive school., Model was developed in collaboration with interest groups, students and parents., Interventions were developed on universal, selective and indicated levels., Abstract The purpose of this paper is to describe a participatory action research process on the development of a professional practice model of mental health nurses in mental health promotion in a comprehensive school environment in the city of Oulu, Finland. The developed model is a new method of mental health promotion for mental health nurses working in comprehensive schools. The professional practice model has been developed in workshops together with school staff, interest groups, parents and students. Information gathered from the workshops was analysed using action research methods. Mental health promotion interventions are delivered at three levels: universal, which is an intervention that affects the whole school or community; selective, which is an intervention focusing on a certain group of students; and indicated, which is an individually focused intervention. All interventions are delivered within the school setting, which is a universal setting for all school-aged children. The interventions share the goal of promoting mental health. The purposes of the interventions are enhancing protective factors, reducing risk factors relating to mental health problems and early identification of mental health problems as well as rapid delivery of support or referral to specialized services. The common effect of the interventions on all levels is the increase in the experience of positive mental health. [ABSTRACT FROM AUTHOR]

Plasma from the Earth’s magnetosheath has previously been observed inside the magnetosphere. Inhomogeneities in the magnetosheath plasma, here called plasmoids, can impact the magnetopause and doing so set up a polarizing field that allows it to penetrate the magnetopause and enter the magnetosphere. A set of simulations of plasmoids with different dimensions is presented in this paper. For plasmoids that are longer than those previously published, waves propagating upstream from the barrier are found. It is also found that the penetration process causes the part of the plasmoid that is upstream of the barrier to rotate. The role of plasmoid width and cross sectional shape in penetration is studied, and for plasmoids that are less than half an ion gyroradius wide, the plasmoid is compressed to obtain a vertically oriented elliptical cross section, regardless of the initial shape. When the initial plasmoid width exceeds the ion gyroradius, the plasmoid still penetrates through a mechanism involving a potential that propagates upstream from the magnetic barrier. [ABSTRACT FROM AUTHOR]