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Stabilization Strategies (stabilization + strategy)
Selected AbstractsOptimising the policy cost of market stabilisation: Which commodity matters most in Ethiopia?JOURNAL OF INTERNATIONAL DEVELOPMENT, Issue 3 2009Kindie Getnet Abstract Unprecedented food crop price spikes in recent years prompted the Ethiopian government to impose grain export ban and to distribute grain stocks as price stabilization strategies. Successful price stabilization and size of public spending for such programs depend, to a large extent, on the choice and targeting of stabilization strategies. In a situation where a single commodity plays a leadership role in the price dynamics of other crops, targeting intervention at such a commodity would provide a useful mechanism to reduce policy cost of price stabilization while achieving commodity-wide stabilization objectives. Using multiple cointegration analysis techniques to generate knowledge useful in targeting price stabilization intervention, this study investigates whether there is a single food crop in Ethiopia, among the three major ones (teff, wheat, and maize), with an exclusive price leadership role in the price formation process of the rest. The results show that maize price plays a leadership role in the dynamics of teff and wheat prices at all markets studied, except that of Addis Ababa teff market. Given the major evidence of a price leadership role of maize, it might be possible to achieve commodity-wide price stabilization objectives through targeting intervention on maize. Such targeted intervention may also prove efficiency in terms of reducing policy cost and public spending. Copyright © 2008 John Wiley & Sons, Ltd. [source] Muscle stabilization strategies in people with medial knee osteoarthritis: The effect of instabilityJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 9 2008Laura C. Schmitt Abstract The sensation of knee instability (shifting, buckling. and giving way) is common in people with medial knee osteoarthritis (OA). Its influence on knee stabilization strategies is unknown. This study investigated the influence of knee instability on muscle activation during walking when knee stability was challenged. Twenty people with medial knee OA participated and were grouped as OA Stable (OAS) (n,=,10) and OA Unstable (OAU) (n,=,10) based on self-reported knee instability during daily activities. Quadriceps strength, passive knee laxity, and varus alignment were assessed and related to knee instability and muscle cocontraction during walking when the support surface translated laterally. Few differences in knee joint kinematics between the groups were seen; however, there were pronounced differences in muscle activation. The OAU group used greater medial muscle cocontraction before, during, and following the lateral translation. Self-reported knee instability predicted medial muscle cocontraction, but medial laxity and limb alignment did not. The higher muscle cocontraction used by the OAU subjects appears to be an ineffective strategy to stabilize the knee. Instability and high cocontraction can be detrimental to joint integrity, and should be the focus of future research. © 2008 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 26:1180,1185, 2008 [source] Stability and hydrolysis kinetics of spirosuccinimide type inhibitors of aldose reductase in aqueous solution and retardation of their hydrolysis by the target enzymeJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 4 2008Masuo Kurono Abstract The stability and the hydrolysis kinetics of spirosuccinimide type aldose reductase (AR) inhibitors, SX-3030 (racemate) and its optical enantiomers (R - and S -isomers), were investigated in aqueous solution. The hydrolysis followed pseudo-first-order kinetics and showed significant pH dependence. Maximum solution stability was observed below pH 2.4, whereas the hydrolysis was gradually catalyzed by hydroxide ion at neutral to alkaline pH while the compounds exhibiting moderate pH-independent stability at acidic to neutral conditions (pH 4,7) to enable oral administration. A pK of 3.7 was obtained from the pH-rate profile, but this kinetically derived pK is approximately 2 pH units below the pK of the parent compounds, suggesting the presence of an acidic intermediate involved in the hydrolysis process. These findings, together with structural analysis, support the notion that the hydrolysis would proceed via nucleophilic attack of a water molecule or hydroxide ion on the scissile carbonyl bond of the succinimide ring to form a succinamic acid intermediate that has a ,-keto acid structure, followed by decarboxylation to give a racemized succinimide ring-opened product. On the other hand, the interconversion of the R - and S -isomers did not occur during hydrolysis; however, the hydrolysis of the R -isomer was markedly suppressed by the target enzyme AR whereas that of the S -isomer was not, indicating a high degree of complementarity of interacting surfaces between the R -isomer and the enzyme. The results in the present study could provide useful clues for facilitating the appropriate stabilization strategies as well as for evaluating the pharmacological effects on target tissues in vivo, and suggested that the R -isomer may be a suitable candidate as AR inhibitor. © 2007 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 97:1468,1483, 2008 [source] An adaptive stabilization strategy for enhanced strain methods in non-linear elasticityINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING, Issue 11 2010Alex Ten Eyck Abstract This paper proposes and analyzes an adaptive stabilization strategy for enhanced strain (ES) methods applied to quasistatic non-linear elasticity problems. The approach is formulated for any type of enhancements or material models, and it is distinguished by the fact that the stabilization term is solution dependent. The stabilization strategy is first constructed for general linearized elasticity problems, and then extended to the non-linear elastic regime via an incremental variational principle. A heuristic choice of the stabilization parameters is proposed, which in the numerical examples proved to provide stable approximations for a large range of deformations, different problems and material models. We also provide explicit lower bounds for the stabilization parameters that guarantee that the method will be stable. These are not advocated, since they are generally larger than the ones based on heuristics, and hence prone to deteriorate the locking-free behavior of ES methods. Numerical examples with two different non-linear elastic models in thin geometries and incompressible situations show that the method remains stable and locking free over a large range of deformations. Finally, the method is strongly based on earlier developments for discontinuous Galerkin methods, and hence throughout the paper we offer a perspective about the similarities between the two. Copyright © 2009 John Wiley & Sons, Ltd. [source] Tunable Bacterial Agglutination and Motility Inhibition by Self-Assembled Glyco-NanoribbonsCHEMISTRY - AN ASIAN JOURNAL, Issue 11 2007Yong-beom Lim Dr. Abstract We explored a method of controlling bacterial motility and agglutination by using self-assembled carbohydrate-coated ,-sheet nanoribbons. To this aim, we synthesized triblock peptides that consist of a carbohydrate, a polyethylene glycol (PEG) spacer, and a ,-sheet-forming peptide. An investigation into the effect of PEG-spacer length on the self-assembly of the triblock peptides showed that the PEG should be of sufficiently length to stabilize the ,-sheet nanoribbon structure. It was found that the stabilization of the nanoribbon led to stronger activity in bacterial motility inhibition and agglutination, thus suggesting that antibacterial activity can be controlled by the stabilization strategy. Furthermore, another level of control over bacterial motility and agglutination was attained by co-assembly of bacteria-specific and -nonspecific supramolecular building blocks. The nanoribbon specifically detected bacteria after the encapsulation of a fluorescent probe. Moreover, the detection sensitivity was enhanced by the formation of bacterial clusters. All these results suggest that the carbohydrate-coated ,-sheet nanoribbons can be developed as promising agents for pathogen capture, inactivation, and detection, and that the activity can be controlled at will. [source] | ||||||||||