The Problem of Capacity Addition in Multi-user Elastic Demand Communication Networks

In this paper we consider some properties on prices under flow control in a network that is to be shared by noncooperative users. Each user is faced with an optimization problem which is formulated as the minimization of its own criterion subject to constraint on the flows of the other users. The operating points of the network are the Nash equilibria of the underlying routing game. Our objective is to study the behavior of prices of all users when the network designer needs to allocate capacities to network links. For parallel links topologies, we show that degradation of the performances such as prices will not take place, as well as the users may find it beneficial to improve their requests     

Chiral liquid chromatography tandem mass spectrometry in the determination of the configuration of glyceric acid in urine of patients with D-glyceric and L-glyceric acidurias

Glyceric acid is a highly polar chiral carboxylic acid that is usually not detected during routine organic acid analysis. Increased excretion is observed in two phenotypically distinct and rare inherited metabolic diseases, D-glyceric aciduria, and L-glyceric aciduria (also known as primary hyperoxaluria type 2). The determination of the exact configuration of the excreted glyceric acid is necessary for the accurate diagnosis of D-glyceric aciduria and for the differentiation between type 1 and type 2 primary hyperoxaluria. The separation of the two stereoisomers was achieved using a narrow-bore ristocetin A glycopeptide antibiotic silica gel bonded column. Triethylamine acetate at pH 4.1 with 10% methanol was used as mobile phase. The column was directly interfaced to a triple quadrupole tandem mass spectrometer and the electrospray ion source was operated in the negative ion mode. Three parent-to-daughter transitions were employed to specifically detect eluting glyceric enantiomers from essentially untreated urine samples. The two forms of glyceric acid were satisfactorily separated at 3.6 and 4.5 min. Application of the method led to the confirmation of three cases of D-glyceric aciduria from three different families. Two other cases are suspected to be L-glyceric aciduria but further confirmation is needed. The method allowed the detection of the glyceric acid stereoisomers in control urine where it was found without exception that L-glyceric was the predominate metabolite.     

Lead-Free Semiconductors with High Absorption: Insight into the Optical Properties of K2GeSnBr6 and K2GeSnI6 Halide Double Perovskites

JETP Letters - Structural, electronic and optical properties for halide double perovskites compounds K2GeSnBr6 and K2GeSnI6 are studied in this work. Based on the (FP-LAPW) method, the previous...     

On some algorithms for limiting average Markov decision processes

We consider limiting average Markov decision processes (MDP) with finite state and action spaces. We propose some algorithms to determine optimal strategies for deterministic and general MDPs. These algorithms are based on graph theory and the construction of levels in some aggregated MDP.     

Chemical composition and anticandidal properties of the essential oil isolated from aerial parts of Cotula cinerea: a rare and threatened medicinal plant in Morocco

The chemical composition and anticandidal properties of the essential oil of Moroccan Cotula cinerea aerial parts have been examined. GC-MS data were used to identify 24 constituents. Oxygenated monoterpenes constituted the main fraction with trans-thujone (41.4%), cis-verbenyl acetate (24.7%), 1,8-cineole (8.2%) and camphor (5.5%) as the major components. The anticandidal activity of the essential oil was evaluated using a panel of human pathogenic fungi (Candida albicans CCMM L4 and CCMM L5, C. krusei CCMM L10, C. glabrata CCMM L7 and C. parapsilosis CCMM L18). The oil showed high anticandidal activity against all investigated strains with minimal inhibitory concentrations of 3.2 to 4.7 mg/mL depending on the tested yeast and 5.9 mg/mL as a minimal candidicidal concentration value. These findings add significant information to the pharmacological activity of Cotula cinerea essential oil, which may present a good alternative to antibiotics for the treatment of resistant strains of Candida.     

Antioxidant and antimicrobial activities of Withania frutescens

In the present study, we report for the first time the antioxidant and antimicrobial activities of Withania frutescens (L.) Pauquy roots and leaves. Total phenolic content was determined using the Folin-Ciocalteu method and antioxidant activity was evaluated by the DPPH free radical scavenging and reducing power methods. Antimicrobial activity tests were carried out against ten bacterial species involved in nosocomial infections and two opportunistic clinical yeast isolates. The ethyl acetate and n-butanol leaf fractions exhibited the highest DPPH radical scavenging activity with IC50 = 4.53 +/- 0.12 and 8.49 +/- 0.46 microg/mL, respectively. The n-butanol root fraction showed the greatest reducing power comparable with that of quercetin at 0.4 mg/mL. The dichloromethane leaf fraction exhibited the highest antibacterial activity against both Gram-positive and Gram-negative bacteria with MIC values ranging between 50 and 400 microg/mL, depending on the tested bacteria. However, none of the examined extracts exhibited anticandidal activity. The polyphenol and glycowithanolide constituents appeared to be responsible for the antioxidant capacity of W. frutescens, whereas the observed antimicrobial activity may be due to the presence of withanolides.     

Hierarchical algorithms for discounted and weighted Markov decision processes

We consider a discrete time finite Markov decision process (MDP) with the discounted and weighted reward optimality criteria. In [1] the authors considered some decomposition of limiting average MDPs. In this paper, we use an analogous approach for discounted and weighted MDPs. Then, we construct some hierarchical decomposition algorithms for both discounted and weighted MDPs.