Let's inhibit our excitement: The relationships between Stroop, behavioral disinhibition, and the frontal lobes.

Objective: The Stroop (Stroop, 1935) is a frequently used neuropsychological test, with poor performance typically interpreted as indicative of disinhibition and frontal lobe damage. This study tested those interpretations by examining relationships between Stroop performance, behavioral disinhibition, and frontal lobe atrophy. Method: Participants were 112 patients with mild cognitive impairment or dementia, recruited through UCSF's Memory and Aging Center. Participants received comprehensive dementia evaluations including structural MRI, neuropsychological testing, and informant interviews. Freesurfer, a semiautomated parcellation program, was used to analyze 1.5T MRI scans. Behavioral disinhibition was measured using the Neuropsychiatric Inventory (Cummings, 1997; Cummings et al., 1994) Disinhibition Scale. The sample (n = 112) mean age was 65.40 (SD = 8.60) years, education was 16.64 (SD = 2.54) years, and Mini-Mental State Examination (MMSE; Folstein et al., 1975) was 26.63 (SD = 3.32). Hierarchical linear regressions were used for data analysis. Results: Controlling for age, MMSE, and color naming, Stroop performance was not significantly associated with disinhibition (β = 0.01, ΔR2 = 0.01, p = .29). Hierarchical regressions controlling for age, MMSE, color naming, intracranial volume, and temporal and parietal lobes, examined whether left or right hemisphere regions predict Stroop performance. Bilaterally, parietal lobe atrophy best predicted poorer Stroop (left: β = 0.0004, ΔR2 = 0.02, p = .002; right: β = 0.0004, ΔR2 = 0.02, p = .002). Of frontal regions, only dorsolateral prefrontal cortex atrophy predicted poorer Stroop (β = 0.001, ΔR2 = 0.01, p = .03); left and right anterior cingulate cortex atrophy predicted better Stroop (left: β = ?0.003, ΔR2 = 0.01, p = .02; right: β = ?0.004, ΔR2 = 0.01, p = .02). Conclusion: These findings suggest Stroop performance is a poor measure of behavioral disinhibition and frontal lobe atrophy even among a relatively high-risk population. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Plasmon-enhanced second-harmonic generation from ionic self-assembled multilayer films

We have demonstrated large enhancements of the effective second-order nonlinear susceptibility (chi(2)) of ionic self-assembled multilayer (ISAM) films, causing a film with just 3 bilayers to be optically equivalent to a 700-1000 bilayer film. This was accomplished by using nanosphere lithography to deposit silver nanoparticles on the ISAM film, tuning the geometry of the particles to make their plasmonic resonances overlap the frequency of optical excitation. An enhancement in the efficiency of second harmonic generation (SHG) by as much as 1600 times was observed. Even though this is already a large value, we suggest that further refinements of the techniques are expected to lead to additional enhancements of similar or larger magnitude.     

Cofiring coal and dairy biomass in a 29 kWt furnace

Cofiring biomass with fossil fuels is emerging as a viable option for promoting the use of low quality renewable biomass fuels including energy crops. In the current work, dairy biomass (DB) is evaluated as a cofiring fuel with coal in a small scale 29 kW_t boiler burner facility. Two types of coal (Texas lignite, TXL and Wyoming Powder River Basin coal, WYO) and two forms of partially composted DB fuels were investigated (low ash separated solids LA-PC-SepSol-DB and high ash soil surface HA-PC-SoilSurf-DB). Proximate and ultimate analyses performed on both coals and both DBs reveal the following: higher heating value (HHV) of 28,460–29,590 kJ/kg for dry ash free (DAF) coals and 21,450 kJ/kg for DB; nitrogen loading of 0.36 and 0.48 kg/GJ for WYO and TXL, respectively and 1.50 and 2.67 kg/GJ for the LA-PC-SepSol-DB and the HA-PC-SoilSurf-DB respectively; sulfur loading of 0.15 and 0.42 kg/GJ WYO and TXL, respectively and 0.33 and 0.43 kg/GJ for the LA-PC-SepSol-DB and the HA-PC-SoilSurf-DB respectively; ash loading from 3.10 to 8.02 kg/GJ for the coals and from 11.57 to 139 kg/GJ for the DB fuels.     

A Requirements Driven Framework for Benchmarking Semantic Web Knowledge Base Systems

A key challenge for the semantic Web is to acquire the capability to effectively query large knowledge bases. As there will be several competing systems, we need benchmarks that will objectively evaluate these systems. Development of effective benchmarks in an emerging domain is a challenging endeavor. In this paper, we propose a requirements driven framework for developing benchmarks for semantic Web knowledge base systems (SW KBSs). In this paper, we make two major contributions. First, we provide a list of requirements for SW KBS benchmarks. This can serve as an unbiased guide to both the benchmark developers and personnel responsible for systems acquisition and benchmarking. Second, we provide an organized collection of techniques and tools needed to develop such benchmarks. In particular, the collection contains a detailed guide for generating benchmark workload, defining performance metrics, and interpreting experimental results     

Changes in absorbance at 413 nm in plasma from three rodent species exposed to phosgene

Mice, rats and guinea pigs were exposed to phosgene (COCl2), a highly irritating and oxidizing gas. Animals were exposed to 87 mg/m3 phosgene for 20 min in a whole-body exposure chamber. Within 55-65 minutes after the start of exposure, plasma was scanned spectrophotometrically from 200-600 nm. A distinct and significant increase in area under the curve in the Soret band region at 413 nm was observed in plasma from phosgene-exposed animals when compared with air-exposed controls in all three species. These peaks were consistent with hemoglobin, an indication that the integrity of the erythrocyte membrane had been compromised by exposure. An erythrocyte osmotic fragility assay on blood from mice exposed to phosgene indicated that 30% less NaCl was needed to cause 50% hemolysis compared to air-exposed mice. These results suggest a new mechanism of phosgene-induced acute lung injury that may be linked, in part, to a direct attack on the erythrocyte membrane.