Facilitation of detection by clinical history generally has been found with a single abnormality per image but not with multiple abnormalities. Multiple abnormalities per image can occasion a ..."satisfaction-of-search" effect in which detection of one lesion is reduced in the presence of other distant lesions. Our experiment studied the combined effect of multiple abnormalities and clinical history on accuracy.
Detection of native lesions was measured 1) with histories suggestive of the native abnormality; 2) with these histories and added simulated pulmonary nodules; and 3) with the same added nodules and histories suggestive of metastatic disease. These conditions also were compared with those of a previous experiment that were similar but included no history.
Detection was substantially improved for appropriately prompted abnormalities even in the presence of a pulmonary nodule. In fact, satisfaction of search was not found in the presence of an appropriate history. Detection of unprompted abnormalities was unchanged when prompts indicated other abnormalities actually present. Prompted abnormalities were detected earlier in search.
History appears to direct perceptual resources to the prompted abnormalities, thereby alleviating satisfaction of search. The presence of nodules yielded a small but consistent reduction in total search time for searches involving false responses, suggesting that satisfaction of search may depend more on reduction in search time than had been indicated by previous research.
Previous studies in mature fetal sheep have shown that alcohol depresses cerebral blood flow (CBF), cerebral O2 consumption (CMRO2), and cerebral glucose consumption (CMRglu). This effect earlier in ...gestation might contribute to the pathogenesis of fetal alcohol syndrome. Physiologic studies of immature fetal sheep have demonstrated lower CBF, CMRO2, and CMRglu as well as a blunted vasodilatory response to hypoxia compared with mature fetal sheep. The purpose of this study was to determine whether immature fetal responses to alcohol are blunted compared with near-term fetal responses. We studied seven immature fetal sheep in utero at 92 +/- 1 d gestation (term = 147 d) 2 d after placement of vascular catheters. Pure ethanol (1 g/kg) was infused i.v. to the mother over 1 h. We measured CBF and myocardial blood flow by radioactive microspheres and calculated CMRO2 and CMRglu using arterial and sagittal sinus O2 and glucose concentrations. At a fetal ethanol concentration of 33 + 8 mmol/L (150 +/- 37 mg/dL), there were no significant changes in CBF, CMRO2, or CMRglu. There was mild hypoglycemia (glucose concentration = 1.05 +/- 0.2 versus 1.33 +/- 0.2 mM baseline) and lactic acidemia (lactate concentration = 1.29 +/- 0.3 versus 1.07 +/- 0.2 mM baseline). Cardiovascular variables were unchanged as was myocardial blood flow. The immature fetal sheep brain shows no significant cerebrovascular and metabolic response to acute alcohol intoxication compared with mature fetal sheep. Mild hypoglycemia and lactic acidemia did develop. The reason for the developmental differences in response to alcohol and their relationship to fetal alcohol syndrome remain to be elucidated.
The evaluation of familial glomerulonephritis in patients with IgA nephropathy who were from central and eastern Kentucky resulted in the discovery of potentially related pedigrees containing 14 ...patients. An additional 17 members of the pedigrees had clinical glomerulonephritis, and 6 had "chronic nephritis" noted on their death certificates. Six patients with IgA nephropathy had a common ancestor. In addition, both parents of six patients with the disease came from families with other cases of IgA nephropathy. No single HLA haplotype or antigen was found in all the patients with IgA nephropathy. Our data on these pedigrees strongly support an inherited mechanism in the pathogenesis of IgA nephropathy in some patients.
The differences between union and nonunion workers' perceptions of the fairness of the workers' compensation claims process are examined. The hypothesis tested is that union members should perceive ...this process as more fair due to union voice. The data were collected in a survey of injured workers in Michigan who had filed a workers' compensation claim. The empirical results indicate that unions have little impact on the perceived fairness of the claims process and that the main contribution of unions is the provision of a complaint mechanism. Forty-two percent of union members believed that they had been treated unfairly and that their expectations of services from union representatives were not met. If procedural justice in the disability claim process is to be effectively achieved for more injured union members, injured workers must receive improved union services, including the provision of information and dispute resolution assistance within the firm.
Low-k fluorocarbon films have been deposited by pulsed plasma chemical vapor deposition (CVD) and their thermal stabilities have been examined. We have observed and identified at least two mechanisms ...for thermal decomposition. We have been able to eliminate the most labile decomposition route by increasing substrate temperature during deposition. Enhanced decomposition due to ex-situ oxygen exposure has also been observed.
Process creation and development that advance integrated circuit device technology and minimize environmental impact of device manufacture are goals of the Environmentally Benign Semiconductor ...Manufacturing (ESBM) Engineering Research Center (Tucson, Arizona). The Center is working on projects concerning CMP processes, replacement perfluorocompounds (PFC) etching chemistries and low-k dielectric materials. CMP is a critical process for interconnect and device technologies and an enabling technology for dielectric planarization, shallow trench isolation, metal plug formation and advanced copper damascene processes. The goal of the EBSM Center is to develop methods that minimize CMP consumption and waste. PFC are a class of highly stable, infrared-absorbing gases believed to contribute to global warming. The Center wants to replace PFC with novel compounds that do not produce by-products. Meanwhile, photoimagable dielectrics would dramatically reduce the number of manufacturing steps and their associated water, chemical and energy consumption.
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