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We report the first voxel-based morphometric (VBM) study to examine cerebral grey and white matter and cerebrospinal fluid (CSF) using computational morphometry in never-medicated, first-episode psychosis (FEP). Region-of-interest (ROI) analysis was also performed blind to group membership. 26 never-medicated individuals with FEP (23 with DSM-IV schizophrenia) and 38 healthy controls had MRI brain scans. Groups were balanced for age, sex, handedness, ethnicity, paternal socio-economic status, and height. Healthy controls were recruited from the local community by advertisement. Grey matter, white matter, and CSF: global brain volume ratios were significantly smaller in patients. Patients had significantly less grey matter volume in L and R caudate nuclei, cingulate gyri, parahippocampal gyri, superior temporal gyri, cerebellum and R thalamus, prefrontal cortex. They also had significantly less white matter volume in the R anterior limb of the internal capsule fronto-occipital fasciculus and L and R fornices, and significantly greater CSF volume especially in the R lateral ventricle. Excluding the 3 subjects with brief psychotic disorder did not alter our results. Our data suggest that fronto-temporal and subcortical-limbic circuits are morphologically abnormal in never-medicated, schizophrenia. ROI analysis comparing the schizophrenia group (n=23) with the healthy controls (n=38) confirmed caudate volumes were significantly smaller bilaterally by 11%, and lateral ventricular volume was significantly larger on the right by 26% in the patients. Caudate nuclei and lateral ventricular volume measurements were uncorrelated (Pearson correlation coefficient 0.30, p=0.10), ruling out the possibility of segmentation artefact. Ratio of lateral ventricle to caudate volume was bilaterally significantly increased (p

A fully integrated low-voltage RF receiver front end for 5 GHz radio applications, implemented in a standard 0.18 μm CMOS technology, is presented. The receiver consists of a differential low noise amplifier, an active mixer, and a quadrature voltage-controlled oscillator. The complete receiver is packaged in a standard 24-pin ceramic flat pack and consumes 56 mW from a 0.8 V supply. Measurement results show that the receiver has an overall noise figure of 7 dB, a −1 dBm input-referred IIP3, and 22 dB of image rejection. A stand-alone single-ended version of the LNA is also presented. Simple mechanisms for tuning the gain and the centre frequency of the LNA are proposed. With a supply voltage of 1 V, the LNA provides a power gain of 13.2 dB, has a noise figure of 2.5 dB, and over 10 dB of gain control and 360 MHz of frequency tuning. The LNA still operates well from a supply voltage as low as 0.7 V, providing a power gain of 7 dB.