Roosevelt University

About: Roosevelt University is a education organization based out in Chicago, Illinois, United States. It is known for research contribution in the topics: Electron paramagnetic resonance & Population. The organization has 751 authors who have published 1482 publications receiving 44299 citations.

High-Affinity Binding Site for Copper(II) in Human and Dog Serum Albumins (an EPR Study)

Abstract: Spectroscopic studies have been performed to investigate the high-affinity binding site for copper in human serum albumin (HSA) and dog serum albumin (DSA). A new approach based on exposure to albumin of the copper in the form of a well-characterized histidine (his) chelate has been adopted. This technique has been shown to minimize interaction at the lower affinity sites. The analysis of the S-band EPR spectrum of [Cu(his)2] at pH 7.3 revealed the major component is a complex formed with two histidines in a histamine-like coordination. Detailed analysis of S-band and X-band EPR and optical spectra of [Cu(II)−HSA] revealed that copper forms a complex with HSA involving α-NH2 terminal, two deprotonated peptide nitrogens (NH of Ala2, and NH of His3), and the imidazole nitrogen of His3 in a square planar arrangement. The spectral data were found to be independent of pH in the range 4.5−9.0 and did not confirm axial Asp1 carboxylate chelation. The EPR study of [Cu(II)−DSA] complex at pH 7.3 confirmed the pres...

The predictive and interactive effects of equity sensitivity in teamwork-oriented organizations

Abstract: Many studies have investigated the relationship between equity sensitivity and other variables of organizational importance. Although theoretical grounds support a link between equity sensitivity and job performance, to date no studies have found equity sensitivity to be a valid predictor of non self-reported job performance in field research. The two field studies reported here empirically support this link and demonstrate that equity sensitivity may also interact with personality traits in predicting job performance. Limitations of the current investigations and future research are discussed. Copyright © 2001 John Wiley & Sons, Ltd.

Computer-Assisted Instruction to Enhance the Reading Comprehension of Struggling Readers: A Review of the Literature:

Abstract: This literature review synthesizes the effects of computer-assisted instruction to enhance the reading comprehension of students with disabilities and struggling readers from 1985–2009. First, it addresses research that investigates the impact on comprehension when students are presented with computerized versus printed reading material. Second, it reviews work using computerized readers to enhance comprehension by compensating for reading difficulties. Finally, it considers research on a variety of tools used to help students gain meaning from the text with which they are engaged, often through Web-linked hypertext. Computer-based tools offer students with learning disabilities and reading difficulties interlinked support for reading. Intervention results are mixed, with many showing positive effects but not consistently so. Future research is needed to gauge the overall effectiveness of hypermedia supports on comprehension.

Development of superficial white matter and its structural interplay with cortical gray matter in children and adolescents.

Abstract: Healthy human brain undergoes significant changes during development. The developmental trajectory of superficial white matter (SWM) is less understood relative to cortical gray matter (GM) and deep white matter. In this study, a multimodal imaging strategy was applied to vertexwise map SWM microstructure and cortical thickness to characterize their developmental pattern and elucidate SWM-GM associations in children and adolescents. Microscopic changes in SWM were evaluated with water diffusion parameters including fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD) in 133 healthy subjects aged 10-18 years. Results demonstrated distinct maturational patterns in SWM and GM. SWM showed increasing FA and decreasing MD and RD underneath bilateral motor sensory cortices and superior temporal auditory cortex, suggesting increasing myelination. A second developmental pattern in SWM was increasing FA and AD in bilateral orbitofrontal regions and insula, suggesting improved axonal coherence. These SWM patterns diverge from the more widespread GM maturation, suggesting that cortical thickness changes in adolescence are not explained by the encroachment of SWM myelin into the GM-WM boundary. Interestingly, age-independent intrinsic association between SWM and cortical GM seems to follow functional organization of polymodal and unimodal brain regions. Unimodal sensory areas showed positive correlation between GM thickness and FA whereas polymodal regions showed negative correlation. Axonal coherence and differences in interstitial neuron composition between unimodal and polymodal regions may account for these SWM-GM association patterns. Intrinsic SWM-GM relationships unveiled by neuroimaging in vivo can be useful for examining psychiatric disorders with known WM/GM disturbances.

Role of the [Fe4S4] cluster in mediating disulfide reduction in spinach ferredoxin:thioredoxin reductase

Abstract: Thioredoxin reduction in plant chloroplasts is catalyzed by a unique class of disulfide reductases which use a one-electron donor, [Fe2S2]2+,+ ferredoxin, and has an active site involving a disulfide in close proximity to a [Fe4S4]2+ cluster. In this study, spinach ferredoxin:thioredoxin reductase (FTR) reduced with stoichiometric amounts of reduced benzyl viologen or frozen under turnover conditions in the presence of thioredoxin is shown to exhibit a slowly relaxing S = 1/2 resonance (g = 2.11, 2.00, 1.98) identical to that of a modified form of the enzyme in which one of the cysteines of the active-site disulfide is alkylated with N-ethylmaleimide (NEM-FTR). Hence, in accord with the previous proposal [Staples, C.R., Ameyibor, E., Fu, W., Gardet-Salvi, L., Stritt-Etter, A.-L., Schurmann, P., Knaff, D.B., and Johnson, M.K. (1996) Biochemistry 35, 11425-11434], NEM-FTR is shown to be a stable analogue of a one-electron-reduced enzymatic intermediate. The properties of the Fe-S cluster in NEM-FTR have been further investigated by resonance Raman and electron nuclear double resonance spectroscopies; the results, taken together with the previous UV-visible absorption, variable temperature magnetic circular dichroism, and resonance Raman data, indicate the presence of a novel type of [Fe4S4]3+ cluster that is coordinated by five cysteinates with little unpaired spin density delocalized onto the cluster-associated cysteine of the active-site disulfide. While the ligation site of the fifth cysteine remains undefined, the best candidate is a cluster bridging sulfide. On the basis of the spectroscopic and redox results, mechanistic schemes are proposed for the benzyl viologen-mediated two-electron-reduction of FTR and the catalytic mechanism of FTR. The catalytic mechanism involves novel S-based cluster chemistry to facilitate electron transfer to the active-site disulfide resulting in covalent attachment of the electron-transfer cysteine and generation of the free interchange cysteine that is required for the thiol-disulfide interchange reaction with thioredoxin.