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Notes: The optical beam induced current (OBIC) technique was applied using a scanning optical microscope (SOM) to study n-Cds/p-CdTe thin film solar cells which had been subjected to different post-deposition treatments. High spatial resolution maps were obtained of the current collection with and without an applied reverse bias. The quantum efficiency of the devices was also measured with high spatial resolution. The results both quantify and illustrate vividly the manner in which the well known CdCl2 treatment increases collection efficiency. The high uniformity in the best cells indicates that grain boundaries do not play a substantial role in limiting collection efficiency. © 1996 American Institute of Physics.

Notes: Abstract Idiopathic focal foveolar hyperplasia (FFH) is a rare cause of gastric outlet obstruction in infants. We present two cases, including the first reported association with infantile hypertrophic pyloric stenosis. The diagnostic ultrasound appearance of FFH is described. Optimal treatment is surgical excision of the involved mucosa with pyloroplasty or pyloromyotomy.

Notes: Abstract Perioperative heat loss is a potentially serious complication of surgery in infants. The influence of laparoscopic surgery on perioperative hypothermia has not previously been documented. We reviewed heat loss in 26 infants undergoing laparoscopic pyloromyotomies compared with 42 control patients having the standard open procedure over the same time period. The mean fall in temperature in the laparoscopic group was −0.69 °C compared with −0.47 °C in the open group. This difference was not significant, with a P value of 0.077. This may reflect the small sample size and the relatively short duration of this procedure with few instrument changes. There was a trend for increased heat loss in the laparoscopic group, which might have implications for longer and more complex laparoscopic procedures in infants.

Notes: Abstract A case is reported of an isolated torsion of the left fallopian tube in a 12-year-old premenarchal girl, and the relevant literature is reviewed. This would seem to be an infrequent cause of acute abdominal pain in girls, and is rarely diagnosed preoperatively. The correct treatment is detorsion of a viable tube, or salpingectomy if ischaemia and necrosis have occurred.

Notes: Abstract Benign, non-parasitic splenic cysts are an uncommon cause of splenomegaly in children. Potentially they may enlarge, causing pain, rupture, or haemorrhage, or become infected. Traditional management has been total splenectomy. We report two cases of true epithelial-lined splenic cysts successfully treated by partial splenectomy using an oxidised cellulose gauze ‘sandwich' technique.

Notes: Abstract Idiopathic focal foveolar hyperplasia (FFH) is a rare cause of gastric outlet obstruction in infants. We present two cases, including the first reported association with infantile hypertrophic pyloric stenosis. The diagnostic ultrasound appearance of FFH is described. Optimal treatment is surgical excision of the involved mucosa with pyloroplasty or pyloromyotomy.

Notes: Abstract Benign, non-parasitic splenic cysts are an uncommon cause of splenomegaly in children. Potentially they may enlarge, causing pain, rupture, or haemorrhage, or become infected. Traditional management has been total splenectomy. We report two cases of true epithelial-lined splenic cysts successfully treated by partial splenectomy using an oxidised cellulose gauze ‘sandwich’ technique.

Notes: Abstract We describe a case of synchronous torsion of testicular appendages, a previously unreported cause of bilateral scrotal pain. Exploration and excision was curative.

Notes: Abstract. Twenty-eight tidal creeks were sampled along the South Carolina coast in the summer of 1995 to determine the levels of sediment trace metal contamination associated with different types and varying levels of human development in their watersheds. The particle size and total organic carbon (TOC) content of creek sediments in developed watersheds (i.e., industrial, urban, and suburban) were similar to that in watersheds with little or no development (i.e., forested or reference). Those trace metals commonly associated with urban and industrial sources, including Cu, Cr, Pb, Zn, Cd, and Hg, were in significantly higher concentrations in tidal creeks located in industrial/urban watersheds compared to the suburban and forested watersheds. Sediment trace metal concentrations were similar for creeks located in suburban and forested watersheds and 2 to 10 times lower than the creeks located in industrial/urban watersheds. Concentrations of trace metals primarily associated with the natural weathering of basement rock, including Al, Fe, As, Ni, and Mn, were not significantly different among watershed types. Four of the tidal creek–salt marsh systems were extensively sampled from the creek channel to the marsh-upland interface to characterize sediment trace metal spatial distributions within creek-marsh systems. Sediment particle size, TOC, and trace metal concentrations varied spatially within each creek-marsh system depending on the type of development in the watershed and the probable source of metals. The creek-marsh system selected to represent the industrial development had significantly higher “anthropogenic” trace metal concentrations compared to the other creek-marsh systems. This system also had trace metal distributional patterns that appeared to be associated with several localized sources of metals on the marsh surface. Both the “anthropogenic” and “natural” trace metal concentrations andspatial distributions were similar among and within the forested and suburban creek-marsh systems.

Notes: Abstract. Twenty-eight tidal creeks along the South Carolina coast were sampled during the summer of 1995 to determine the levels of sediment contamination including organic chemicals (i.e., polycyclic aromatic hydrocarbons [PAHs], polychlorinated biphenyls [PCBs], and DDT and its metabolites) associated with different types and varying levels of watershed development (i.e., industrial/urban, suburban, forested, and salt marsh). Organic analysis utilized high-performance liquid chromatography (HPLC) with fluorescence detection and capillary gas chromatography–ion trap mass spectrometry (GC-ITMS) for PAHs, and gas chromatography with electron capture detection (GC-ECD) for pesticides and PCBs. Results indicated that creeks with industrial/urban watersheds had significantly higher concentrations of PAHs, PCBs, and DDT compared with creeks with suburban and forested (reference) watersheds. The suburban watershed class of creeks had concentrations of half the PAH analytes and the total PCBs which exceeded the concentrations found in the forested watershed class of creeks. The spatial distribution of organic contaminants was evaluated in four of these tidal creek–salt marsh systems representing urban/industrial, suburban, and forested watersheds, from the creek channel to the adjacent uplands. The distribution of organic contaminants within each representative creek was not concordant with the total organic carbon or the clay content of the sediment. The representative industrial/urban creek-marsh system, Diesel Creek, had the highest concentration of PAHs in the creek channel and the highest concentration of PCBs and DDT on the marsh surface, primarily in the upper portion of the system. The representative suburban creek-marsh system, Shem Creek, had elevated levels of both PAHs and PCBs throughout the entire system. This system also had one site with a total PAH concentration of 324,000 ppb and a total DDT concentration that was 20–100 times higher than the other sites. One of the representative forested creek-marsh systems, Rathall Creek, had low levels of the three organic contaminants except for one sampling site that had PAH concentrations a factor of 10 higher than the other sites. The other representative forested creek-marsh system, Long Creek, had low levels of PAHs and PCBs, but elevated levels of DDT were observed, particularly in the upper portion on the marsh surface. The results of this study suggest that (1) anthropogenic alteration of the land cover in the watersheds of tidal creek–salt marsh systems may increase the organic contaminant loadings in the sediment, and (2) tidal creek–salt marsh sediments, particularly in the creek channel, are repositories and potentially conduits of organic contaminants from the upland environment to the deeper estuarine areas.