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Exhibit Differences (exhibit + difference)
Selected AbstractsBioelectrochemical Characterization of Horseradish and Soybean PeroxidasesELECTROANALYSIS, Issue 21 2009Marco Frasconi Abstract Heme peroxidase are ubiquitous enzymes catalyzing the oxidation of a broad range of substrates by hydrogen peroxide. In this paper the bioelectrochemical characterization of horseradish peroxidase (HRP) and soybean peroxidase (SBP), belonging to class III of the plant peroxidase superfamily, was studied. The homogeneous reactions between peroxidases and some common redox mediators in the presence of hydrogen peroxide have been carried out by cyclic voltammetry. The electrochemical characterization of the reactions involving enzyme, substrate and mediators concentrations allowed us to calculate the kinetic parameters for the substrate,enzyme reaction (KMS) and for the redox mediator,enzyme reaction (KMM). A full characterization of the direct electron transfer kinetic parameters between the electrode and enzyme active site was also performed by opportunely modeling data obtained from cyclic voltammetry and square wave voltammetry experiments. The experimental data obtained with immobilized peroxidases show enhanced direct electron transfer and excellent electrocatalytical performance for H2O2. Despite the structural similarities and common catalytic cycle, HRP and SBP exhibit differences in their substrate affinity and catalytic efficiency. Basing on our results, it can be concluded that peroxidase from soybean represents an interesting alternative to the classical and largely employed one obtained from horseradish as biorecognition element of electrochemical mediated biosensors. [source] Prognosis of follicular lymphomasHEMATOLOGICAL ONCOLOGY, Issue 2 2006Stefano Luminari Abstract Follicular lymphoma (FL) is as an indolent neoplasia with median survival measured in decades. Nevertheless, some patients have poor progression-free survival and overall survival. Several treatment approaches are proposed for patients with FL, however criteria to rationalize treatment decisions are lacking. Studies have been performed to build up prognostic indices that are useful for defining risk-adapted treatment recommendations. Available indices are based on parameters that have an independent role in predicting patient survival and that are variably correlated with the features of the disease, with the characteristics of the patient and with the effects of treatment. Two new prognostic indices have recently been proposed for FL: the Italian Lymphoma Intergroup (ILI) index and the Follicular Lymphoma International prognostic Index (FLIPI). Both indices are based on large series of patients and exhibit differences in their ability to discriminate between patients with different probabilities of survival. In recent years, with the advent of gene expression profile studies, our knowledge of the biology of FL is changing as novel data become available about the lymphoma cell and about the role of the microenvironment; these studies have already provided novel prognostic tools for identifying patients with more aggressive disease. Further data and large international cooperative studies are needed to translate into clinical practice the novel acquisitions of biology and therapeutics. Copyright © 2006 John Wiley & Sons, Ltd. [source] Testing the effect of individual color morphology on immune response in bush-cricketsINSECT SCIENCE, Issue 5 2010Åsa Berggren Abstract, Despite the growing interest in how an individual's immune response is correlated to morphological and ecological factors, little empirical data has been available from wild insect populations. Many insects have different color morphs and exhibit differences in immune responses. Links are expected to exist between body colors and immune function in insects, because the same biochemical precursors involved in the immune response are responsible for melanin-based color markings. In this study, I assay the immune response of two different color morphs of 377 wild-caught bush-crickets, Metrioptera roeseli, from 20 populations by measuring individual encapsulation responses to a surgically implanted nylon monofilament. There was no difference between green and brown bush-cricket morphs (low melanin vs high melanin investment in cuticula color respectively) and their ability to mount an immune response to the implant. Further study is needed on the relationship between color morphology and immune response in wild insects, and whether trade-offs occur between factors during an insect's development phase and long-term health. [source] IAS Versus U.S. GAAP: Information Asymmetry,Based Evidence from Germany's New MarketJOURNAL OF ACCOUNTING RESEARCH, Issue 3 2003CHRISTIAN LEUZ abstract Motivated by the debate about globally uniform accounting standards, this study investigates whether firms using U.S. generally accepted accounting principles (GAAP) vis-à-vis international accounting standards (IAS) exhibit differences in several proxies for information asymmetry. It exploits a unique setting in which the two sets of standards are put on a level playing field. Firms trading in Germany's New Market must choose between IAS and U.S. GAAP for financial reporting, but face the same regulatory environment otherwise. Thus, institutional factors such as listing requirements, market microstructure, and standards enforcement are held constant. In this setting, differences in the bid-ask spread and share turnover between IAS and U.S. GAAP firms are statistically insignificant and economically small. Subsequent analyses of analysts' forecast dispersion, initial public offering underpricing, and firms' standard choices corroborate these findings. Thus, at least for New Market firms, the choice between IAS and U.S. GAAP appears to be of little consequence for information asymmetry and market liquidity. These findings do not support widespread claims that U.S. GAAP produce financial statements of higher informational quality than IAS. [source] Synthesis and characterization of polypyrrole rod doped with p -toluenesulfonic acid via micelle formationJOURNAL OF APPLIED POLYMER SCIENCE, Issue 6 2008Duk Ki Kim Abstract Rod-type polypyrrole (PPY) doped with p -toluenesulfonic acid (TSA) was synthesized by chemical oxidative polymerization via a self-assembly process. The shape of the PPY particles is mainly determined by the ratio of TSA/pyrrole (PY) and feed rate of the oxidant. Particle of different shapes (rod, grain, and partially rod) exhibit differences in morphology, electrical properties, dispersity, and thermal properties. Wide-angle X-ray diffraction patterning analysis was used to investigate the mechanism of rod formation. The effect of the TSA concentration on the PPY structure was investigated using Fourier transform infrared spectroscopy. The PPY rods doped with TSA exhibited better electrical conductivity than granular PPY doped with TSA, and their dispersity and thermal stability were also higher. Self-orientation of PPY in the micelles of TSA and high crystallinity of the rod particles led to improved thermal stability. Hence, the decomposition temperature of the polymer chain was considerably increased. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2008 [source] Extraordinary diversity in vasopressin (V1a) receptor distributions among wild prairie voles (Microtus ochrogaster): Patterns of variation and covariationTHE JOURNAL OF COMPARATIVE NEUROLOGY, Issue 4 2003Steven M. Phelps Abstract The vasopressin V1a receptor is a gene known to be central to species differences in social behavior, including differences between the monogamous prairie vole and its promiscuous congeners. To examine how individual differences compare with species differences, we characterize variability in the expression of the vasopressin V1a receptor (V1aR) in a large sample of wild prairie voles. We find a surprising degree of intraspecific variation in V1aR binding that does not seem attributable to experimental sources. Most brain regions exhibit differences between upper and lower quartiles that are comparable to differences between species in this genus. Regions that are less variable have been implicated previously in regulating monogamous behaviors, suggesting that the lack of variation at these sites could reflect natural selection on mating system. Many brain regions covary strongly. The overall pattern of covariation reflects the developmental origins of brain regions. This finding suggests that shared mechanisms of transcriptional regulation may limit the patterns of gene expression. Such biases may shape both the efficacy of selection and the pattern of individual and species differences. Overall, our data indicate that the prairie vole would be a useful model for exploring how individual differences in gene expression influence complex social behaviors. J. Comp. Neurol. 466:564,576, 2003. © 2003 Wiley-Liss, Inc. [source] | ||||||||||