Application of ABC and XYZ Analysis to Inventory Optimization at a Commercial Enterprise

Inventory management at an enterprise is the essential logistics function. Reducing inventory maintenance costs and optimizing the range of goods while focusing on consumer demand analy-sis are inextricably linked to inventory management methods. This article describes the differentiated inventory management model of the ABC-XYZ classification matrix in relation to the inven-tory of Karandash LLC commercial enterprise (Tomsk). Inventory management is a highly relevant issue, since the company has several branches, cooperates with many suppliers, and its range of office supplies includes more than 30 000 items. The ABC-XYZanalysis of the inventory of this commercial enterprise allowed us to determine strategies for optimizing inventory and to identify the groups that should be removed from the range, and, vice versa, should be available in stock due to constant demand

Effects of Monovalent Anions of the Hofmeister Series on DPPC Lipid Bilayers Part I: Swelling and In-Plane Equations of State

Aiming to improve understanding of the mechanisms behind specific anion effects in biological systems we have studied the effects of sodium salts of simple monovalent anions belonging to the Hofmeister series on the bilayers of the zwitterionic lipid 1,2-dipalmitoyl-sn-glycero-3-phosphocholine using small-angle x-ray scattering and the osmotic stress technique. NaCl, NaBr, NaNO3, NaI, and NaSCN were used in this investigation. The electrolytes were found to swell the bilayers and to increase the area per lipid headgroup at each value of the osmotic pressure, suggesting the association of anions with the bilayer-lipid interfaces. The effects follow the Hofmeister series with SCN− inducing the most pronounced changes. “Ion competition” experiments with mixed NaI/NaCl solutions at total salinity 0.1 and 0.5 M revealed that the effect of ions on the lipid equation-of-state is roughly linear at low concentrations, but strongly nonlinear at high concentrations. The experimental results are fitted in a companion article to provide “binding” or “partitioning” constants of anions in the lipid bilayers