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This paper presents a case study of the ground‐borne vibrations generated by small wind turbines. This is of particular importance for assessing the possible impact on the detection capabilities of the International Monitoring System seismic array at Eskdalemuir in Scotland. Measurements were gathered from a selection of small wind turbines (≤50 kW), from three different manufacturers, varying in hub height, power and construction using a range of accelerometers and seismometers fixed to the tower and buried in the adjacent ground at increasing distances. Previous studies have shown that medium and large turbines generate harmonic vibrations. Planning guidelines exist but have inadvertently led to a ban on the deployment of individual small‐turbines within 50 km of the array. This study investigates whether their inclusion in these guidelines is necessary. Vibration levels on the tower are in the region of 10−3m/sqrt(Hz), are transferred into the ground and decay rapidly away from the turbine (10−5m/sqrt(Hz) in the ground at 200 m). The spectral content of the vibrations shows variations between the turbines, but each have peaks in the band of interest for Eskdalemuir. Further, sources of the peaks in the spectra are identified as either originating from the blades’ rotation or the resonant modes of the turbines. Analysis of the relationship between wind speed and seismic amplitude on the tower shows an exponential trend, individual to each wind turbine and the frequency band of interest. Similarly, analysis of the seismic amplitude between the tower and foundation shows that this can be described by a power law, but this is individual to each turbine. It is our opinion that there is little requirement to include turbines of 50 kW or less in planning guidelines outside the statutory exclusion zone of 10 km, but each turbine should be considered on an individual basis.

A two‐dimensional COSY‐based localization sequence was designed to allow the in vivomonitoring of proton metabolites in rat brain [particularly γ‐aminobutyric acid (GABA), glutamine, taurine and myo‐inositol]. The sequence incorporated OSIRIS signal localization, B1‐insensitive water suppression and phase‐sensitive COSY acquisition. The method was used to study the effects of the GABA‐transaminase inhibitor vigabatrin on rat brain metabolite concentrations. Wistar rats were treated daily for 3 days with an oral dose of vigabatrin (200 mg/kg, n= 4). Localized COSY spectra were obtained during a 120 min acquisition from a 270 µl central brain voxel and compared with nine untreated control animals. Significant elevations were observed in GABA (267% of control, p< 0.005, Mann–Witney test), glutamine (130% of control, p< 0.005) and taurine (113% of control, p< 0.05). Changes in GABA and taurine were consistent with previous data on the action of Vigabatrin, and support a previously hypothesized link between these compounds. The increase in glutamine was more surprising and may reflect the balance between the level and/or site of GABA‐transaminase inhibition and downregulation of GABA synthesis. Copyright © 2003 John Wiley & Sons, Ltd.

A two-dimensional COSY-based localization sequence was designed to allow the in vivo monitoring of proton metabolites in rat brain [particularly γ-aminobutyric acid (GABA), glutamine, taurine and myo-inositol]. The sequence incorporated OSIRIS signal localization, B1-insensitive water suppression and phase-sensitive COSY acquisition. The method was used to study the effects of the GABA-transaminase inhibitor vigabatrin on rat brain metabolite concentrations. Wistar rats were treated daily for 3 days with an oral dose of vigabatrin (200 mg/kg, n = 4). Localized COSY spectra were obtained during a 120 min acquisition from a 270 µl central brain voxel and compared with nine untreated control animals. Significant elevations were observed in GABA (267% of control, p &lt; 0.005, Mann–Witney test), glutamine (130% of control, p &lt; 0.005) and taurine (113% of control, p &lt; 0.05). Changes in GABA and taurine were consistent with previous data on the action of Vigabatrin, and support a previously hypothesized link between these compounds. The increase in glutamine was more surprising and may reflect the balance between the level and/or site of GABA-transaminase inhibition and downregulation of GABA synthesis. Copyright © 2003 John Wiley & Sons, Ltd.

Huntington's disease (HD) is an autosomal dominant condition involving progressive neurodegeneration, primarily in the corpus striatum and cerebral cortex. We have used in vivomagnetic resonance spectroscopy (MRS) to assess specific neuronal markers in transgenic mice (R6/1 line) expressing exon 1 of the human huntingtin gene with an expanded CAG repeat. Levels of N-acetylaspartate (NAA), an indicator of healthy neuronal function, were significantly reduced (26) in the corpus striatum of HD mice relative to wild-type littermates at 5 months of age. However, levels of cholines and creatine phosphocreatine were not altered in the HD mice. Expression of dopamine- and cAMP-regulated phosphoprotein, 32 kDa (DARPP-32), was assessed by immunohistochemistry in the striatum of HD mice and found to be downregulated by 5 months and, even more dramatically, at 11 months of age. In contrast, expression of calbindin was not significantly decreased in HD mice. Our results suggest that the observed decreases in DARPP-32 and NAA may contribute to aberrant receptor signalling and neuronal dysfunction in HD.