The biomass dynamics of cyanobacteria in an annual cycle determined by confocal laser scanning microscopy

We recently published a method for estimating cyanobacteria biomass in delta microbial mats from the Ebro river using confocal laser scanning microscopy (CLSM). The present paper uses this method for identifying different groups of cyanobacteria and for determining their biomass dynamics. Microcoleus chthonoplastes and the Lyngbya-Oscillatoria were the most important contributors to the cyanobacterial biomass throughout the study. Biomass values ranged from 1.29 to 6.55 mgC/cm2 sediment for Microcoleus chthonoplastes, and from 128 microgC/cm2 to 3.16 mgC/cm2 sediment for Lyngbya-Oscillatoria. This technique is useful for determining biomass and for studying filamentous cyanobacteria as well as ramified eukaryotic cells. Confocal serial sections through the samples can be obtained. Two-dimensional images from the samples can be used to calculate the biomass of individual cells.     

Psychological assessment of candidates for solid organ transplantation.

The role of psychologists, who can assist in preparing clients for transplant surgery and support them postsurgery to sustain the complex maintenance protocol, is outlined. An overview of specific procedures used in the psychological evaluation and treatment of solid organ transplant patients, a discussion of general issues involved in treating these patients, and case vignettes are provided. As transplants become more common, the need for additional psychologists as part of multidisciplinary treatment teams increases. Because many patients live great distances from the transplant center, community psychologists may be enlisted to treat organ transplant patients and to collaborate with psychologists on transplant teams. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Relation between Melting and Textural Properties of Process Cheddar Cheese

Meltability and textural characteristics were evaluated in 48 batches of process Cheddar cheese prepared in pilot plant equipment. Correlation between melting spread at 139°C and cohesiveness at 21°C was positive and large. Prolongation of cooking up to 15 min at 74°C lowered meltability and cohesiveness. Within the range of weighted average ages of cheese (3 to 5.8 mo), no relation between melting spread or cohesiveness and age was consistent.     

Cardiovascular phenotype characterization in mice by high resolution magnetic resonance imaging

9. Conclusion Due to its high temporal and spatial resolution, magnetic resonance imaging meets the requirements for accurate and robust in vivo visualization of the murine cardiovascular system. As an intrinsically three-dimensional imaging technique, it allows for quantification of LV volumes without relying on geometric models. Therefore, MRI is uniquely suited for the investigation of morphologic and functional changes in models of heart failure. The potential application of MRI in the mouse comprises visualization of cardiovascular anatomy and pathology in newborn and adult mice, detection of LV geometric and functional changes both acutely and chronically, visualization of cardiac microstructures such as cardiac valves and coronary arteries, and characterization and quantification of arteriosclerotic plaques in major murine arteries. Furthermore, MR spectroscopy applied to the mouse heart can give important information on in vivo myocardial metabolism. Thus, we feel confident that high resolution MRI may substantially contribute to the understanding of the basic mechanisms of a variety of cardiovascular diseases.     

Oscillation and convergence behaviours exhibited in an ‘unstable’ second‐order digital filter with saturation‐type non‐linearity

This letter explains the oscillatory behaviours exhibited in a second‐order digital filter with saturation‐type non‐linearity via the Hopf bifurcation theorem. It is shown that depending on the bifurcation parameter, the state variables may converge to zero even when the eigenvalues of the system matrix are outside the unit circle. Copyright © 2004 John Wiley & Sons, Ltd. abstract     

Ultra‐Performance Liquid Chromatography‐Mass Spectrometry Analysis of Free and Esterified Oxygenated Derivatives from Docosahexaenoic Acid in Rat Brain

Docosahexaenoic acid (DHA), a prominent long‐chain fatty acid of the omega‐3 family, is present at high amount in brain tissues, especially in membrane phospholipids. This polyunsaturated fatty acid is the precursor of various oxygenated lipid mediators involved in diverse physiological and pathophysiological processes. Characterization of DHA‐oxygenated metabolites is therefore crucial for better understanding the biological roles of DHA. In this study, we identified and measured, by ultrahigh‐performance liquid chromatography coupled with tandem mass spectrometry, a number of oxygenated products derived from DHA in exsanguinated and nonexsanguinated brains. These metabolites were found both in free form and esterified in phospholipids. Interestingly, both (R)‐ and (S)‐monohydroxylated fatty acid stereoisomers were observed free and esterified in phospholipids. Monohydroxylated metabolites were the main derivatives; however, measurable amounts of dihydroxylated products such as protectin DX were detected. Moreover, exsanguination allowed discriminating brain oxygenated metabolites from those generated in blood. These results obtained in healthy rats allowed an overview on the brain oxygenated metabolism of DHA, which deserves further research in pathophysiological conditions, especially in neurodegenerative diseases.