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Ninety subjects with severe and disabling psychiatric conditions, predominantly schizophrenia, participated in a controlled-outcome trial of the cognitive component of Integrated Psychological Therapy (IPT), a group-therapy modality intended to reestablish basic neurocognitive functions. The cognitive therapy was delivered to subjects in the experimental condition during intensive 6-month treatment periods. Control subjects received supportive group therapy. Before, during, and after the intensive treatment period, all subjects received an enriched regimen of comprehensive psychiatric rehabilitation, including social and living skills training, optimal pharmacotherapy, occupational therapy, and milieu-based behavioral treatment. IPT subjects showed incrementally greater gains compared with controls on the primary outcome measure, the Assessment of Interpersonal Problem-Solving Skills, suggesting that procedures that target cognitive impairments of schizophrenia spectrum disorders can enhance patients' response to standard psychiatric rehabilitation, at least in the short term, in the domain of social competence. There was equivocal evidence for greater improvement in the experimental condition on the Brief Psychiatric Rating Scale disorganization factor and strong evidence for greater improvement on a laboratory measure of attentional processing. There was significant improvement in both conditions on measures of attention, memory, and executive functioning, providing support for the hypothesis that therapeutic procedures that target impaired cognition enhance response to conventional psychiatric rehabilitation modalities over a 6-month timeframe.

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Despite numerous investigations, the dynamical origins of the Medieval Climate Anomaly and the Little Ice Age remain uncertain. A major unresolved issue relating to internal climate dynamics is the mode and tempo of Atlantic meridional overturning circulation variability, and the significance of decadal-to-centennial scale changes in Atlantic meridional overturning circulation strength in regulating the climate of the last millennium. Here we use the time-constrained high-resolution local radiocarbon reservoir age offset derived from an absolutely dated annually resolved shell chronology spanning the past 1,350 years, to reconstruct changes in surface ocean circulation and climate. The water mass tracer data presented here from the North Icelandic shelf, combined with previously published data from the Arctic and subtropical Atlantic, show that surface Atlantic meridional overturning circulation dynamics likely amplified the relatively warm conditions during the Medieval Climate Anomaly and the relatively cool conditions during the Little Ice Age within the North Atlantic sector.

[1] We present new annually resolved d18 O, d13 C, Mg/Ca, and Sr/Ca ratio records for two shells of the fast growing Mediterranean fan mussel Pinna nobilis, collected from proximal Spanish coast sea grass meadows. The relationship between the potential geochemical proxies and ontogenetic and environmental controlling factors is investigated. Specifically, the use of shell Mg/Ca and Sr/Ca ratios as potential calcification temperature proxies, the latter calculated from measured shell d 18O values, has been assessed. The d 18O cycles along the growth axis indicate that our P. nobilis specimens are $10.5 and $4.5 years old Shell Sr/Ca ratios do not exhibit any consistent interannual cyclicity and are not correlated to temperature. A subtle ontogenetic effect on shell Mg/Ca ratios was observed during the first 4.5 years of recorded growth but was highly evident during the organism's later growth years. In P. nobilis shells, different mechanisms influence ontogenetic variation in shell Mg/Ca and d 18 O records. Shell Mg/Ca ratios from the first 4.5 years of growth correlate significantly to temperature, in a best fit relationship described by the equation Mg/Ca = 17.16 ± 1.95 * exp(0.022 ± 0.004 * T). P. nobilis shell Mg/Ca records therefore are a valid temperature proxy only during an early growth phase. For the same range of temperatures, shell Mg/Ca ratios in P. nobilis are approximately 1/3 lower than those reported for inorganic calcite but 3 to 4 times higher than in another bivalve species, Mytilus trossulus, and 4 to 16 times higher than in foraminifera. We suggest these offsets are due to a higher degree of similarity between seawater and calcification-fluid composition in P. nobilis than in other bivalves and foraminifera. The observed shell Mg/Ca ratio change per°C of 2.2% also is lower than that observed for inorganic and other biogenic calcites. Our findings strongly support taxon-and species-specific Mg/Ca-temperature relationships for bivalves and other calcifying organisms. An appreciation of the physiology and calcification mechanisms of any biogenic carbonate archive therefore is paramount prior to the application of stable-isotope and element/Ca ratio proxies for paleotemperature reconstructions.

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Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) was used to determine the elemental composition of the incremental growth record in the shells of longevous, (~35 yr old) horse mussels Modiolus modiolus. Concentrations of the contaminant metals Cu, Pb and Zn were determined from shells collected in 1984 from 2 sites in the southern North Sea, an 'impacted dump' site and a 'control' site distant from known point source inputs. The age of each shell was determined from the pattern of annual growth lines present in thin shell sections, and each growth line was assigned a date, thus allowing annual concentrations of these elements to be determined. Using LA-ICP-MS, concentrations of the metals were determined in 5 replicate laser ablations (sizẽ 100 × 200 µm), from individual summer and winter growth lines along the length of each of 3 shells from the dump site and 3 shells from the control site. A significant effect of age (year) on Cu, Pb and Zn concentrations in the shells from both sites was apparent, indicating changing concentrations with time. Significant seasonal (summer/winter) effects were only obvious in the concentrations of Pb and Zn in the shells; a non-significant difference in seasonal incorporation of Cu was observed. Concentrations of all 3 metals were significantly elevated in the dump site shells compared with the control site shells. Pearson correlation coefficients, determined for pairs of metals in the shells from both sites, indicated a higher number of significant positive correlations in the concentrations amongst the metals in the dump site shells than in the control shells during certain periods of the mussels' life. Levels of Cu, Zn and Pb were significantly higher in the dump site shells between 1968 and 1974 than in the period from 1975 to 1979. In the control site shells, although Pb and Zn significantly declined during the same periods, the concentrations were substantially and significantly lower than in the dump site shells. The implementation of the Dumping at Sea Act (in 1974) and the subsequent decline in dumping in the North Sea may have resulted in a decrease in the concentration of metals in the shells from the impacted dump site.