Purpose:To explore the neural correlates of the thalamus by using resting-state functional magnetic resonance (MR) imaging and to investigate whether thalamic resting-state networks (RSNs) are disrupted in patients with mild traumatic brain injury (MTBI). Materials and Methods:This HIPAA-compliant study was approved by the institutional review board, and written informed consent was obtained from 24 patients with MTBI and 17 healthy control subjects. The patients had varying degrees of symptoms, with a mean disease duration of 22 days. The restingstate functional MR imaging data were analyzed by using a standard seed-based whole-brain correlation method to characterize thalamic RSNs. Student t tests were used to perform comparisons. The association between thalamic RSNs and performance on neuropsychologic and neurobehavioral measures was also investigated in patients with MTBI by using Spearman rank correlation. Results:A normal pattern of thalamic RSNs was demonstrated in healthy subjects. This pattern was characterized as representing relatively symmetric and restrictive functional thalamocortical connectivity, suggesting an inhibitory property of the thalamic neurons during the resting state. This pattern was disrupted, with signifi cantly increased thalamic RSNs ( P Յ .005) and decreased symmetry ( P = .03) in patients with MTBI compared with healthy control subjects. Increased functional thalamocortical redistributive connectivity was correlated with diminished neurocognitive functions and clinical symptoms in patients with MTBI.

In this study, venous oxygen saturation and oxygen metabolic changes in multiple sclerosis (MS) patients were assessed using a recently developed T2-relaxation-under-spin-tagging (TRUST) magnetic resonance imaging (MRI), which measures the superior sagittal venous sinus blood oxygenation (Yv) and cerebral metabolic rate of oxygen (CMRO 2 ), an index of global oxygen consumption. Thirty patients with relapsing-remitting MS and 30 age-matched healthy controls were studied using TRUST at 3 T MR. The mean expanded disability status scale (EDSS) of the patients was 2.3 (range, 0 to 5.5). We found significantly increased Yv (P < 0.0001) and decreased CMRO 2 (P = 0.003) in MS patients (mean±s.d.: 65.9%±5.1% and 138.8±35.4 lmol per 100 g per minute) as compared with healthy control subjects (60.2% ± 4.0% and 180.2 ± 24.8 lmol per 100 g per minute, respectively), implying decrease of oxygen consumption in MS. There was a significant positive correlation between Yv and EDSS and between Yv and lesion load in MS patients (n = 30); on the contrary, there was a significant negative correlation between CMRO 2 and EDSS and between CMRO 2 and lesion load (n = 12). There was no correlation between Yv and brain atrophy measures. This study showed preliminary evidence of the potential utility of TRUST in global oxygen metabolism. Our results of significant underutilization of oxygen in MS raise important questions regarding mitochondrial respiratory dysfunction and neurodegeneration of the disease.

Andrews and Bonta identified the following criminogenic needs as important to reducing offending: substance use, antisocial cognition, antisocial associates, family and marital relations, employment, and leisure and recreational activities. This study examines dynamic criminogenic need changes across a 12-month period and identifies which need changes are the best predictors of criminal offending and illicit drug use among a sample of drug-involved probationers who participated in an intervention (N = 251). Probationers had significant changes in several need areas, and treatment participation moderated some changes. Probationers who had reductions in criminally involved family members they associate with, improved work performance, and decreased alcohol use had the greatest reductions in offending. Those who increased time spent engaged in leisure and recreational activities were less likely to self-report subsequent drug use. These findings suggest that certain dynamic need changes may be more important than others, and designing interventions to impact these needs might improve outcomes.

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Abstract. Ship emissions in and around ports are of interest for urban air quality management in many harbour cities. We investigated the impact of regional and local ship emissions on urban air quality for 2012 conditions in the city of Gothenburg, Sweden, the largest cargo port in Scandinavia. In order to assess the effects of ship emissions, a coupled regional- and local-scale model system has been set up using ship emissions in the Baltic Sea and the North Sea as well as in and around the port of Gothenburg. Ship emissions were calculated with the Ship Traffic Emission Assessment Model (STEAM), taking into account individual vessel characteristics and vessel activity data. The calculated contributions from local and regional shipping to local air pollution in Gothenburg were found to be substantial, especially in areas around the city ports. The relative contribution from local shipping to annual mean NO2 concentrations was 14 % as the model domain average, while the relative contribution from regional shipping in the North Sea and the Baltic Sea was 26 %. In an area close to the city terminals, the contribution of NO2 from local shipping (33 %) was higher than that of road traffic (28 %), which indicates the importance of controlling local shipping emissions. Local shipping emissions of NOx led to a decrease in the summer mean O3 levels in the city by 0.5 ppb (∼2 %) on average. Regional shipping led to a slight increase in O3 concentrations; however, the overall effect of regional and the local shipping together was a small decrease in the summer mean O3 concentrations in the city. In addition, volatile organic compound (VOC) emissions from local shipping compensate up to 4 ppb of the decrease in summer O3 concentrations due to the NO titration effect. For particulate matter with a median aerodynamic diameter less than or equal to 2.5 µm (PM2.5), local ship emissions contributed only 3 % to the annual mean in the model domain, while regional shipping under 2012 conditions was a larger contributor, with an annual mean contribution of 11 % of the city domain average. Based on the modelled local and regional shipping contributions, the health effects of PM2.5, NO2 and ozone were assessed using the ALPHA-RiskPoll (ARP) model. An effect of the shipping-associated PM2.5 exposure in the modelled area was a mean decrease in the life expectancy by 0.015 years per person. The relative contribution of local shipping to the impact of total PM2.5 was 2.2 %, which can be compared to the 5.3 % contribution from local road traffic. The relative contribution of the regional shipping was 10.3 %. The mortalities due to the exposure to NO2 associated with shipping were calculated to be 2.6 premature deaths yr−1. The relative contribution of local and regional shipping to the total exposure to NO2 in the reference simulation was 14 % and 21 %, respectively. The shipping-related ozone exposures were due to the NO titration effect leading to a negative number of premature deaths. Our study shows that overall health impacts of regional shipping can be more significant than those of local shipping, emphasizing that abatement policy options on city-scale air pollution require close cooperation across governance levels. Our findings indicate that the strengthened Sulphur Emission Control Areas (SECAs) fuel sulphur limit from 1 % to 0.1 % in 2015, leading to a strong decrease in the formation of secondary particulate matter on a regional scale was an important step in improving the air quality in the city.

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AbstractfMRI has become the method of choice for mapping brain activity in human subjects and detects changes in regional blood oxygenation and volume associated with local changes in neuronal activity. While imaging based on blood oxygenation level dependent (BOLD) contrast has good spatial resolution and sensitivity, the hemodynamic signal develops relatively slowly and is only indirectly related to neuronal activity. An alternative approach termed magnetic source MRI (msMRI) is based on the premise that neural activity may be mapped by MRI with greater temporal resolution by detecting the local magnetic field perturbations associated with local neuronal electric currents. We used a hybrid ms/BOLD MRI method to investigate whether msMRI could detect signal changes that occur simultaneously at the time of the production of well defined event related potentials, the P300 and N170, in regions that previously have been identified as generators of these electrical signals. Robust BOLD activations occurred after some seconds, but we were unable to detect any significant changes in the T2*-weighted signal in these locations that correlated temporally with the timings of the ERPs. IntroductionThere is continuing interest in the development of improved methods for mapping brain function and organization. Functional MRI (fMRI) is one of the most important and useful of current techniques and is based on the sensitivity of MRI to changes in blood oxygenation, flow, and volume that accompany with changes in brain activation [Ogawa, 1990]. The spatial and temporal resolutions of this technique are limited by the nature of the coupling between neuronal electrical activity and the corresponding hemodynamic response. Spatial resolutions on the order of 1 mm and temporal resolutions on the order of 1 sec are readily achieved. There is considerable interest in developing methods to map neural events with greater temporal resolution.Signal transfer along an axon is based on the ability of the membrane to alter its permeability to Na+ and K+ ions. These changes are caused by the opening of voltage-sensitive channels as a result of an approaching action potential. The action potential can be approximated by two oppositely oriented current dipoles whose separation depends on the conduction velocity. The magnitude of each dipole is about 100fAm. Although the precise natures of neural currents are complex, they generate weak magnetic fields within tissue that in principle may affect NMR signals [Cohen, 1984;Nunez, 2001;Bandettini, 2005]. One approach to detecting these fields is to try to measure the spatial displacement induced by neuronal electrical currents by the Lorentz effect [Song, 2001;Truong, 2006]. In addition, several groups have suggested that neural activity may be detected by MRI by measuring the signal losses and/or phase shifts produced by the local magnetic field perturbations associated with the local electric currents [Bodurka, 2002;Xiong, 2003]. This general approach has been termed magnetic source MRI Publisher's...

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