Stand type affects fluxes of volatile organic compounds from the forest floor in hemiboreal and boreal climates

The forest floor is a significant contributor to the stand-scale fluxes of biogenic volatile organic compounds. In this study, the effect of tree species (Scots pine vs. Norway spruce) on forest floor fluxes of volatile organic compounds (VOC) was compared in boreal and hemiboreal climates.Peer reviewe

Explaining job satisfaction and job control: a survey among finnish psychiatrists

Background: Job satisfaction has a major impact on mental health and job performance. Additionally, expected work satisfaction may influence choice of specialization within medicine. Methods: A postal survey was conducted in 2009 among the members (N=1398) of Finnish Psychiatric Association. Out of the members 1132 were still working-aged. All in all 64.8% (N=738) of the working-aged members returned the survey. Only psychiatrists and residents were included in the final cohort of the study (N=665). Factors associated to work satisfaction were studied and a principal component analysis was conducted on factors reported to disturb working. The correlations of factors scores with job satisfaction and job-control were analyzed. Spearman correlation coefficients were calculated between factor scores and work satisfaction. Results: Most respondents (73.8%) were satisfied with their work. Job satisfaction showed a negative correlation with increase in pace of work (rho=-0.24, p&lt;0.001). Job control correlated positively with job satisfaction (rho=0.46, p&lt;0.001). &quot;Working conditions&quot; factor explained 28.6%, &quot;leadership&quot; 8.8%, &quot;failure without support&quot; 7.8%, fear at work 6.5% and &quot;patient records&quot; factors 5.9% of the variation of perceived harmful factors at work. &quot;Working conditions&quot; and &quot;leadership&quot; factors showed the strongest and most significant negative correlations with job satisfaction (rho= -0.45, p&lt;0.001, rho=-0.32, p&lt;0.001, respectively. &quot;Working conditions&quot; associated strongly and significantly with job control (rho=-0.57, p&lt;0.001). Conclusion: Job satisfaction may be better than expected among psychiatrists considering the findings of prevalence estimates of burnout in various other studies. However, employers should put emphasis on matching employers and type of work to promote well-being of their employees.</p

Modeling of Neuronal Growth In Vitro: Comparison of Simulation Tools NETMORPH and CX3D

We simulate the growth of neuronal networks using the two recently published tools, NETMORPH and CX3D. The goals of the work are (1) to examine and compare the simulation tools, (2) to construct a model of growth of neocortical cultures, and (3) to characterize the changes in network connectivity during growth, using standard graph theoretic methods. Parameters for the neocortical culture are chosen after consulting both the experimental and the computational work presented in the literature. The first (three) weeks in culture are known to be a time of development of extensive dendritic and axonal arbors and establishment of synaptic connections between the neurons. We simulate the growth of networks from day 1 to day 21. It is shown that for the properly selected parameters, the simulators can reproduce the experimentally obtained connectivity. The selected graph theoretic methods can capture the structural changes during growth.Peer reviewe

Time Dependence of Charge Transfer Processes in Diamond Studied with Positrons

We have developed a method called optical transient positron spectroscopy and apply it to study the optically induced carrier trapping and charge transfer processes in natural brown type IIa diamond. By measuring the positron lifetime with continuous and pulsed illumination, we present an estimate of the optical absorption cross section of the vacancy clusters causing the brown color. The vacancy clusters accept electrons from the valence band in the absorption process, giving rise to photoconductivity.Peer reviewe

Mapping of serum amylase-1 and quantitative trait loci for milk production traits to cattle chromosome 4

The present study was undertaken to confirm and refine the mapping of a quantitative trait locus in cattle for milk fat percentage that had earlier been reported to be linked to the serum amylase-1 locus, AM1. Five half-sib families from the previous study and 7 new ones were genotyped for nine microsatellite markers spanning chromosome 4. AM1 was mapped between the microsatellite markers BMS648 and BR6303. In a granddaughter design, interval mapping based on multiple-marker regression was utilized for an analysis of five milk production traits: milk yield, fat percentage and yield, and protein percentage and yield. In the families reported on previously, significant effects for fat and protein percentages were detected. In the new families, an effect on milk and fat yields was found. The most likely positions of the quantitative trait locus in both groups of families were in the same area of chromosome 4 in the vicinity of the obese locus. Direct effects of the obese locus were tested for using polymorphism in two closely linked microsatellites located 2.5 and 3.6 top downstream of the coding sequence. No firm evidence was found for an association between the obese locus and the tested traits

Identification of the VAl-ON defect complex in AlN single crystals

In this Rapid Communication, we report positron annihilation results on in-grown and proton irradiation-induced vacancies and their decoration in aluminium nitride (AlN) single crystals. By combining positron lifetime and coincidence Doppler measurements with ab initio calculations, we identify in-grown VAl−ON complexes in the concentration range 10 exp 18 cm exp −3 as the dominant form of VAl in the AlN single crystals, while isolated VAl were introduced by irradiation. Further, we identify the UV absorption feature at around 360 nm that involves VAl.Peer reviewe

3-Chloro-4-(dichloromethyl)-5-hydroxy-2(5H)-furanone (MX) and mutagenic activity in Massachusetts drinking water.

There is limited information on the prevalence of the potent mutagen 3-chloro-4-(dichloromethyl)-5-hydroxy-2(5H)-furanone (MX) in U.S. water supplies. We measured MX concentrations and mutagenic activity in tap water samples from 36 surface water systems throughout Massachusetts. We found MX levels much higher (up to 80 ng/L) than previously reported in the United States. We also evaluated the role of water treatment on mutagenic activity and disinfection by-product formation. After adjusting for other covariates, chloramination and filtration were the most important treatment options for reducing mutagenic activity and disinfection by-product formation. Multiple chlorine application (before and after filtration) was associated with increased mutagenicity. Chlorine dose, pH, and total organic carbon were also associated with mutagenicity, MX, and total trihalomethane (TTHM) concentration. Seasonal variation was evident for MX and mutagenic activity, with higher levels occurring in the spring compared to the fall. In contrast, TTHM concentrations were greater in the fall