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In this paper, we introduce a location-based privacy-preserving authentication protocol (LPA) in vehicular ad hoc networks (VANETs) to address the issue on conditional privacy preservation in which safety messages can be anonymously authenticated by peer vehicles while an authority can trace the sender in a dispute. Specifically, in the LPA protocol, we propose a top-down security system: the top authority (TA) authorizes the roadside units (RSUs) to issue group certificates to the onboard units (OBUs). In addition, we also introduce RSU neighbor set to enhance security and efficiency. We demonstrate the merits of the proposed scheme through extensive analysis and performance evaluation. Copyright © 2011 John Wiley & Sons, Ltd.

Glucagon-like peptide-1 (GLP-1), which is an endogenous insulinotropic peptide that can stimulate islet cells to secret insulin, is a promising new drug candidate for the treatment of type 2 diabetes. However, due to the very short half-life of this peptide, the clinical value of GLP-1 is restricted. A GLP-1 peptide analog that had been altered by deletion of five amino acids from the C-terminus (sGLP-1) was selected and investigated in vivo for the therapeutic effect on GK rats with type II DM (T2DM). The results revealed that sGLP-1 exhibited decreased blood glucose-lowering ability compared to GLP-1 in the first week, as measured after once-daily administration. However, after drug administration for 2 weeks, the blood glucose-lowering effect of sGLP-1 became superior to that of GLP-1. sGLP-1 reduced apoptosis of the old islets, enhanced insulin production, and promoted new islets replication. sGLP-1 is a shorter but more efficient GLP-1 analog for type 2 diabetes management. Because sGLP-1 prolonged the proliferation and recovery of islet cells, the ability to maintain blood glucose (BG) within a normal range was still present 2 weeks after drug withdrawal. These results confirmed the importance of the C-terminus of GLP-1 molecule, and further demonstrated that GLP-1 (7–37) can be truncated till the 32nd amino acid to have a better long-term BG lowing function. This result may imply for the presence of glucagon family clearance receptors in vivo and demonstrates that the C-terminus participates in GLP-1 clearance. Copyright © 2008 European Peptide Society and John Wiley & Sons, Ltd.

Fe-limited cells of the green alga Chlamydomonas reinhardtii (Fe-limited growth rate = 0.3 d−1) reduced extracellular Fe(III) to Fe(II) when Fe(III) was supplied as ferricyanide or Fe(III)-EDTA; Fe(III) reduction was stimulated by light. In both darkness and during photosynthesis, ferricyanide reduction was accompanied by a decrease in cellular NADPH levels, with a concomitant increase in NADP+. NADH and NAD+ levels were not measurably altered during ferricyanide reduction. Furthermore, cellular hexose monophosphate levels declined and 6-phosphogluconate levels increased during ferricyanide reduction. Levels of most glycolytic and tricarboxylic acid cycle intermediates were mostly unaltered. Ferricyanide reduction was also associated with a decrease in cellular ATP levels, a concomitant increase in ADP and AMP, and increased extracellular acidification. The acidification was sensitive to inhibition by the H+-ATPase inhibitor N,N′-dicyclohexylcarbodiimide (DCCD). We conclude that the oxidative pentose phosphate pathway provides reducing equivalents for Fe(III) reduction in darkness and also contributes reducing equivalents to Fe(III) reduction during photosynthesis. The decline in ATP was likely due to activation of the plasma membrane H+-ATPase during ferricyanide reduction and was not directly associated with provision of reducing equivalents.