196,022 research outputs found
Functional properties of hemoglobins from Triturus cristatus
No full textThe functional properties of hemoglobins from Triturus cristatus carnifex have been characterized both from an equilibrium and a kinetic point of view. A special attention has been given to the effect of organic phosphates in view of their role in the modulation of the hemoglobin function. Under stripped conditions newt hemoglobins display a negative Bohr effect which becomes much less pronounced in the presence of 0.2 M inorganic phosphates. The effect of organic phosphates involves not only a drop in the O2 affinity but also a large change in the shape of the O2 Bohr effect which becomes markedly positive in the presence of myo-inositol hexakis(phosphate). The experimental data reported make it possible to give a complete picture of the functional behaviour of newt hemoglobins, making a contribution to clarifying the dependence of the sign of the Bohr effect on the acclimatization temperature of the animals that has been previously reported [Morpurgo, G., Battaglia, P. A. and Leggio, T. (1970) Nature (Lond.) 225, 76--77]
An electrophoretic polymorphism that mimics a true genetic polymorphism in Triturus cristatus carnifex (Amiphibia, Urodela).
No full text
Multispectral images for monitoring fruit ripeness: validation methods
No full textMulti-spectral images have been previously used to classify different kinds of fruits into postharvest maturity classes. Previous research has succeeded in classifying peaches into ripeness clusters, gathering the whole variability of ripeness in the harvest and post-harvest chain (Lleó et al, 2007). The main objective of this work is to correlate fruit image with firmness and other quality traits through the analysis and classification of R-IR images on commercial conditions. MT-firmness and colour Reflectance parameters are used as reference values. The second objective is to develop an automatic procedure, able to classify on line commercial peaches into ripening classes consistently correlated with fruit quality.
During the 2006 season, 500 images (2 images per fruit) including just harvested peaches, and over ripened fruits, in order to simulate commercial conditions, were considered for the generation of 6 ripeness classes. For external validation 1304 images from on season 2006; and 1020 images from season 2007 were analyzed. For both seasons, image-based classes showed constant trends and coherent ranges on their reference values: high percentage (91% for season 2006 and 81% for 2007) of the samples below minimum firmness values for transport (Crisosto, 1996) were classified into clusters 4, 5 or 6. The studied method shows a good potential to characterize the ripening state of the fruits, although further research is required to ensure high reliability of the system
Dr. Duane M. Jackson, Morehouse College, July 2011
No full textThis video is a conversation with Dr. Duane M. Jackson. Dr. Jackson talks about his paper, "Recall and the Serial Position Effect: The Role of Primacy and Recency on Accounting Students' Performance." Jackie Daniel, AUC Woodruff Library, is the interviewer
A simple digital imaging method for dirt detection on eggshells
No full textThe objective of this research was to develop an off-line vision system to detect defective eggshells, i.e., with dirty eggshell, by employing a classification algorithm based on a few logical operations, allowing a further implementation in an on-line grading process. In particular, this work was focused to study the feasibility of identifying and differentiating dirt stains on brown eggshells caused by organic residuals, from natural stains, caused by deposits of pigments. Digital images were acquired from 384 clean and dirty brown eggshells by employing a CCD camera endowed with 15 monochromatic filters (440-940 nm). Each dirty eggshell presented only one kind of defect, i.e., blood stains, feathers and white, clear or dark faces, while clean eggshells did not present organic residuals or evidences of feather, but their external color was characterized by clear or dark natural stains. A MatLab® devoted code was developed in order to classify samples as clean or dirty. The program was constituted by three major steps: first, the research of an opportune combination of monochromatic images in order to isolate the eggshell from the background; second, the detection of the dirt stains; third, the classification of the images samples into the dirty or clean group. The proposed classification algorithm was able to correctly classify near 93% of the samples. The robustness of the proposed classification was observed applying an external validation to a second set of samples, obtaining similar percentage of correctly classified samples (92%)
ERK5/MAPK is activated by TGFbeta in hepatocytes and required for the GSK-3beta-mediated Snail protein stabilization
No full textExtracellular signal-regulated protein kinase 5 (ERK5) is a mitogen-activated protein kinase, specifically activated by MEK5, and involved in the regulation of many cellular functions including proliferation, survival, differentiation and apoptosis. MEK5/ERK5 module is an important element of different signal transduction pathways. The aim of this study was to investigate whether ERK5 participates to the signalling of the multifunctional cytokine TGF beta, known to play an important role in the regulation of hepatic growth. Here, we reported that ERK5 is phosphorylated and activated by TGF beta in hepatocytes, with a rapid and sustained kinetic, through a Src-dependent pathway. Moreover, we demonstrated that ERK5 participates to the TGF beta-induced Snail protein regulation being required for its stabilization. We also found that the functional inactivation of ERK5 impedes the TGF beta-mediated glycogen synthase kinase-3 beta inactivation suggesting this as mechanism responsible for ERK5-mediated Snail stabilization. Thus, results presented in this study uncovered for the first time a role for ERK5 in the TGF beta-induced cellular responses. (c) 2008 Elsevier Inc. All rights reserved
"Reflections on the subject of Emigration from Europe with a view to Settlement in the United States" By M. Carey.
No full text"Reflections on the subject of Emigration from Europe with a view to Settlement in the United States: containing bried sketches of the moral and political character of those states.
By M. Carey, member of the American philosophical, and of the American Antiquarian Society, and author of The Olive Branch, Cindiciae Hibernicae, essays on banking, on political economy, and on internal improvement.
To which are now added the English editor's comments on the subject; together with Important Advice to Emigrants, and Cautions Against Impositions Practiced in the Outports
- …
