Increases in the steady-state levels of PA and PIP2 occur within several minutes of temperature increases from ambient levels of 20-25 degrees click here C to 35 degrees C and above. Similar patterns were observed in heat-stressed Arabidopsis
seedlings and rice leaves. The PA that accumulates in response to temperature increases results in large part from the activation of PLD rather than the sequential action of phospholipase C and diacylglycerol kinase, the alternative pathway used to produce this lipid. Pulse-labelling analysis revealed that the PIP2 response is due to the activation of a PIPK rather than inhibition of a lipase or a PIP2 phosphatase. Inhibitor experiments suggest that the PIP2 response requires signalling through a G-protein, as aluminium fluoride blocks heat-induced PIP2 increases. These results are discussed in the context of the diverse cellular roles played by PIP2 and PA, including regulation of ion channels and the cytoskeleton.”
“Wheat straw fiber-polypropylene (PP) composites selleck screening library were prepared to
investigate the effects of wheat straw fiber content (10, 20, 30, 40, and 50 wt %), fiber size (9, 28, and 35 mesh), and maleic anhydride grafted polypropylene (MAPP) concentration (1, 2, 5, and 10 wt %) on the static and dynamic mechanical properties of the wheat straw fiber-PP composites in this study. The tensile modulus and strength of the composites increased linearly with increasing wheat straw SNX-5422 in vitro fiber content up to 40%, whereas the elongation at break decreased dramatically to 3.78%. Compared with the composites made of the longer wheat straw fiber, the composites made of the fines (>35 mesh) had a slightly higher tensile strength of 31.2 MPa and tensile elongation of 5.39% at break. With increasing MAPP concentration, the composites showed an increase in tensile strength, and the highest tensile strength of 34.0 MPa occurred when the MAPP concentration reached 10 wt %. As wheat straw fiber content increased from 0 to 40%, the flexural modulus of the composites increased gradually from 1335 to 3437 MPa. The MAPP concentration and wheat straw fiber size distribution had no appreciable
effect on the static flexural modulus of the composites. The storage flexural modulus of the composites increased with increasing wheat straw fiber content. The scanning electron microscopy (SEM) observation on the fracture surface of the composites indicated that a high wheat straw fiber content (>30 wt %) resulted in fiber agglomeration and a reduction in interfacial bonding strength. (C) 2009 Wiley Periodicals, fnc. J Appl Polym Sci 113: 1000-1007, 2009″
“Background/Objectives: Molecular mechanisms of congestive heart failure as reflected by alterations of protein expression patterns are still incompletely analyzed. We therefore investigated intraventricular (ie, left ventricular congestive heart failure [LV-CHF] vs. LV-control [CTRL], and right ventricular [RV]-CHF vs.