Catalytic pre-wave of nickel(II) in presence of cocarboxylase (disulfide form) in borate medium

A brief study is made of the nickel(II) polarography in borate medium. The nickel(II) in borate medium gives one or two waves depending on its concentration as well as the medium composition.In a borate medium, cocarboxylase in its disulfide form gives a nickel(II) pre-wave. The effects of the cocarboxylase (disulfide form) concentration, nickel(II) concentration and mercury column height on the pre-wave are described.The effect of neutral salts on the pre-wave is studied and it is seen that an increase in the ionic strength is accompanied by a decrease in pre-wave current, being of decreasing effect in the order K⁺ < Na⁺ < Li⁺. The electrocapillary curves are present, and it is shown that the presence of cocarboxylase (disulfide form) in the solution causes a decrease in the interfacial tension.The results are discussed and a mechanism for the electrode process of the pre-wave is proposed. Using the approximate method for the catalytic currents, nickel(II) and cocarboxylase-thiol are shown to form the catalytic complex in the relationship 1:1.     

Model-driven component adaptation in the context of Web Engineering

Currently, Web-based applications are no longer monolithic and isolated systems but, rather, distributed applications that need to interoperate with third-party systems, such as external Web services, LDAP repositories or legacy applications. When one component provides a service that the Web application requires, it is often not possible to bind the two systems together if they were not programmed to have compatible collaboration specifications. Modeling the adaptation between a Web application and external assets becomes therefore an essential issue in any realistic model-driven development scenario. However, most of the existing Web Engineering proposals do not take this issue into account, or they simply address it at the implementation level (in a platform-specific way). In this work, we discuss the problems involved in dealing with component adaptation within the context of Model-Driven Web Engineering and show how design patterns can help addressing it. We first identify the major interoperability problems that can happen when integrating third-party application or legacy systems into our Web systems, and then propose the mechanisms that need to be put in place at the design level to generate the appropriate specification of adapters that compensate for the possible mismatches and differences. We base our proposal on well-known design patterns as they are established solutions to recurring problems, and the generation of code from them is normally straightforward.     

Participation of phosphatidyl inositol 3-kinase/protein kinase B and ERK1/2 pathways in interleukin-1beta stimulation of lactate production in Sertoli cells

Interleukin-1beta (IL1beta ) belongs to a set of intratesticular regulators that provide the fine-tuning of cellular processes implicated in the maintenance of spermatogenesis. The aim of the present study was to analyze the signaling pathways that may participate in IL1beta regulation of Sertoli cell function. Sertoli cell cultures from 20-day-old rat were used. Stimulation of the cultures with IL1beta showed increments in phosphorylated protein kinase B (PKB), P70S6K, and ERK1/2 levels. A phosphatidyl inositol 3-kinase (PI3K) inhibitor (wortmannin (W)), a mammalian target of rapamycin inhibitor (rapamycin (R)), and a MEK inhibitor (PD98059 (PD)) were utilized to evaluate the participation of PI3K/PKB, P70S6K, and ERK1/2 pathways in the regulation of lactate production by IL1beta . PD and W, but not R, decreased IL1beta-stimulated lactate production. The participation of these pathways in the regulation of glucose uptake and lactate dehydrogenase (LDH) A mRNA levels by IL1beta was also analyzed. It was observed that W decreased IL1beta-stimulated glucose uptake, whereas PD and R did not modify it. On the other hand, PD decreased the stimulation of LDH A mRNA levels by IL1beta , whereas W and R did not modify it. In summary, results presented herein demonstrate that IL1beta stimulates PI3K/PKB-, P70S6K-, and ERK1/2-dependent pathways in rat Sertoli cells. Moreover, these results show that while IL1beta utilizes the PI3K/PKB pathway to regulate glucose transport, it utilizes the ERK1/2 pathway to regulate LDH A mRNA levels. This study reveals that IL1beta utilizes different signal transduction pathways to modify the biochemical steps that are important to regulate lactate production in rat Sertoli cells.     

Low‐cost and high‐performance: VoIP monitoring and full‐data retention at multi‐Gb/s rates using commodity hardware

Voice over IP (VoIP) is increasingly replacing the old public switched telephone network (PSTN) technology. In this new scenario, there are several challenges for VoIP providers. First, VoIP requires a detailed monitoring of both users' quality of service (QoS) and experience (QoE) to a greater extent than in traditional PSTNs. Second, such a monitoring process must be able to track VoIP traffic in high‐speed networks, nowadays typically of multi‐Gb/s rates. Third, recent government directives require that providers retain information from their users' calls. Similarly, the convergence of data and voice services allows operators to provide new services such as full‐data retention, in which users' calls can be recorded for either quality assessment (call centers, QoE) or security purposes (lawful interception). This implies a significant investment in infrastructure, especially in large‐scale networks which require multiple points of measurement and redundancy. This paper proposes a novel methodology, architecture and system to fulfill such challenges, called VoIPCallMon, as well as the data structures and necessary hardware‐tuning knowledge for its development. As distinguishing features, VoIPCallMon provides very high performance, being able to process VoIP traffic on‐the‐fly at high bitrates, novel services and significant cost reduction by using commodity hardware with minimal interference with operational VoIP networks. The performance evaluation shows that the system copes with the VoIP load of real‐world operators. We further evaluated the system performance at a fully saturated 10 Gb/s link and no packet loss was reported, therefore demonstrating the potential of commodity hardware solutions. Copyright © 2014 John Wiley & Sons, Ltd.     

Prebiotic effect of fermented cashew apple (Anacardium occidentale L) juice

Leuconostc mesenteroides B-512F and L. mesenteroides B-742 were cultivated in clarified cashew apple juice to produce prebiotic oligosaccharides. Yeast extract (20 g/L); K₂HPO₄ (g/L) and sucrose (50 g/L) were added to the juice to promote the microbial growth and dextransucrase production. Initial pH was adjusted to 6.5 with H₃PO₄. Fermentations were carried out at 30 °C and 150 rpm for 24 h. The prebiotic effect of the fermented cashew apple juice, containing oligosaccharides, was evaluated through the Lactobacillus johnsonii B-2178 growth. L. johnsonii was incubated for 48 h using fermented cashew apple juice as substrate. Lactobacillus growth was compared to the microbial growth in non-fermented juice and in MRS broth. L. johnsonii growth in the fermented cashew apple juice was threefolds the observed growth in the non-fermented juice.