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This article gives members information about The Society for the History of Psychology. It covers news of Division 26, which includes a letter from President Ben Harris. It also discusses the SHP election results of 2005, a call for presidential nominations, and awards. Then it covers the report on the August, 2005 Meeting of the APA Council of Representatives. Under the History of Psychology Around the World heading, notes from the report of the 2005 annual meeting of Cheiron are provided, as well as a call for papers for the 2006 meeting; information about the Psychology Museum at the University of Sydney, Australia is given; and a research project at the Max Planck Institute for the History of Science in Berlin is described. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Xeroderma pigmentosum complementation group G associated with Cockayne syndrome

Xeroderma pigmentosum (XP) and Cockayne syndrome (CS) are two rare inherited disorders with a clinical and cellular hypersensitivity to the UV component of the sunlight spectrum. Although the two traits are generally considered as clinically and genetically distinct entities, on the biochemical level a defect in the nucleotide excision-repair (NER) pathway is involved in both. Classical CS patients are primarily deficient in the preferential repair of DNA damage in actively transcribed genes, whereas in most XP patients the genetic defect affects both "preferential" and "overall" NER modalities. Here we report a genetic study of two unrelated, severely affected patients with the clinical characteristics of CS but with a biochemical defect typical of XP. By complementation analysis, using somatic cell fusion and nuclear microinjection of cloned repair genes, we assign these two patients to XP complementation group G, which previously was not associated with CS. This observation extends the earlier identification of two patients with a rare combined XP/CS phenotype within XP complementation groups B and D, respectively. It indicates that some mutations in at least three of the seven genes known to be involved in XP also can result in a picture of partial or even full-blown CS. We conclude that the syndromes XP and CS are biochemically closely related and may be part of a broader clinical disease spectrum. We suggest, as a possible molecular mechanism underlying this relation, that the XPGC repair gene has an additional vital function, as shown for some other NER genes.     

High Variability of Phytoplankton Photosynthesis in Response to Environmental Forcing in Oligotrophic Lake Malawi/Nyasa

In southern Lake Malawi, seasonal pelagic chlorophyll means were 1.0 ± 0.3 μg L⁻¹ in the deep mixing season (DMS) (May–August), 0.8 ± 0.3 μg L⁻¹ in the dry stratified season (DSS) (September to November) and 0.7 ± 0.3 μg L⁻¹ in the wet stratified season (WSS) (December to April). Despite the low variability in chlorophyll, there was a wide range in chlorophyll specific photosynthetic activity. The photosynthetic parameters, P^b_m (the light saturated rate) and α^b (the light limited slope), varied significantly among seasons and were highly positively correlated, with lowest values in the DSS and highest values in WSS. During deep mixing, P^b_m did not covary with α^b; and the light saturation index, E_k (=P^b_m/α^b), varied in response to changes in α^b rather than in P^b_m. Phytoplankton appeared to be nutrient deficient at all times but less deficient during deep vertical mixing in the DMS. Average daily rates of integrated phytoplankton primary productivity were lowest in the DSS (337 mg C m⁻² d⁻¹) and highest in the WSS (629 mg C m⁻² d⁻¹) despite nearly identical mean chlorophyll concentrations. Along a near shore transect off the Linthipe River, chlorophyll concentrations were higher and more variable (1.4 ± 1.3 μg L⁻¹), phytoplankton were not strongly nutrient deficient and chlorophyll specific photosynthetic activity was as high or higher than at the offshore station. Estimates of phytoplankton productivity in this tropical great lake must account for spatial and temporal variability in photosynthetic parameters imposed by seasonal changes in mixing dynamics.     

Biomagnification of DDT through the benthic and pelagic food webs of Lake Malawi, East Africa: importance of trophic level and carbon source

Lake Malawi, an East African Rift Valley lake, is internationally renowned for having the highest diversity of fish species in the world, and these cichlids are highly specialized in their dietary habits. In this lake, tissue stable carbon (delta13C) and nitrogen (delta15N) isotopes can be used over several trophic levels to distinguish those consumers relying upon carbon fixed by either benthic or pelagic primary producers. As such, it was possible to contrast the biomagnification of persistent organochlorines through the benthic and pelagic food webs. In 1996 and 1997, food-web organisms were collected from Lake Malawi and analyzed for organochlorines, delta13C and delta15N to determine the factors that affectthe biomagnification of contaminants in a tropical lake. The pesticide DDT was the most predominant pollutant in the biota from Lake Malawi and was found at the highest concentrations in the largest and fattiest fish species. As observed in temperate systems, log-transformed sigmaDDT concentrations in food-web organisms were significantly predicted by delta15N or log lipid (r2 = 0.32 and 0.40, respectively). In addition, the slope of the regression of log sigmaDDT versus delta15N was significantly higher in the pelagic than the benthic food web. These results indicate that pelagic organisms are at greater risk of accumulating these pollutants than biota relying upon benthic primary production.