In the past 20 years a variety of electronic markets have been set-up for the allocation of capacities in road transportation. Although, inefficiencies and cost pressures are high, the electronic markets have not succeeded so far. In this paper we will give an overview of the so-called electronic transportation exchanges and analyze the factors that were involved in the repeated failures. By us...

Electronic intermediaries play an important role in many Web-based electronic markets, adding value for participants by offering services such as matchmaking and trust. This paper presents an economic model of intermediation where the intermediary offers services to two types of actors: consumers and providers. When consumers are heterogeneous, differentiated on their willingness to pay for int...

The ontogenesis and specific activities of pancreatic (trypsin, chymotrypsin, amylase and lipase) and intestinal enzymes (alkaline phosphatase, aminopeptidase N) were investigated in Kutum (Rutilus frisii Kutum) from the onset of exogenous feeding (3 day after hatching, DAH) to the juvenile stage at 50 DAH. Trypsin- and chymotrypsin-specific activity showed similar patterns and increased with l...

acute toxicity (96h-lc50) of potassium permanganate (pm) was determined for caspian kutum rutilus frisii kutum at two size classes (1 and 3 g). static renewal method was used. fish were exposed to different concentrations of pm and mortality was recorded thereafter, until 96 h. exposed fish showed behavioral stress indicators. 96h-lc50 was calculated to be 3.204 (3.147-3.260) mg/l for small fis...

abstract relation between sexual maturity and levels of two main steroid hormones in gonads, 17- estradiol (e2) and testosterone (t) were studied by using histological and radioimmunoassay in female kutum rutilus frisii kutum during spawning season of the southern caspian sea. the study was carried out from february to may 2008 using 105 migrated fish specimens catched from the river sefid-rood...

the current paper investigates non-contestable markets, and through discussing this concept and adopting an interdisciplinary approach investigates the interaction between this concept and the contestable markets. in this regard and from a positive point of view, the current paper aims to disuss the interaction of these two concepts. from a legal and normative point of view, we seek to highligh...

This study proceeds to extract collagen from the skin of Rutilus  kutum, one of  the main and economical species of the Caspian Sea. Acid-soluble collagen (ASC) from the skin of R. kutum was extracted and characterized by SDS-PAGE, FTIR and UV spectrophotometry. Based on the data from the SDS-PAGE and the composition of amino acid, it was probable that the obtained collagen classified as type I...