SDN-DVFS: an enhanced QoS-aware load-balancing method in software defined networks

Cluster Computing - Recently, software defined networks (SDN) has been considered as a promising technology for improving the network performance. However, the load imbalance problem considerably...     

Performance Enhancement of Surface Plasmon Resonance Biosensors Based on Noble Metals-Graphene-WS2 at Visible and Near-Infrared Wavelengths

Plasmonics - In this paper, some biological sensors based on surface plasmon resonance are proposed at visible and near-infrared wavelengths and their performance is improved. The structure of...     

The relationship between hydrophobicity and interfacial tension of proteins.

Charge-free hydrophobic gels of Hjerten et al. (Hjerten, S., Rosengren, J. and Pahlman, S. (1974) J. Chromatogr. 101, 281--288) were used for hydrophobic affinity chromatography. The effective hydrophobicity of proteins was expressed as their retention volumes from columns of butylepoxy- and hexylepoxy-Sepharose 4B. The effective hydrophobicity was also estimated by a partition method of Shanbhag and Axelsson ((1975) Eur. J. Biochem. 60, 17--22) from the partition coefficients of proteins between two phases, poly (ethylene glycol) and dextran. The former contained a hydrophobic ligand, palmitate. A close correlation was observed between the hydrophobicities determined by the two methods. However, no significant relationship was observed between these effective hydrophobicities and the average hydrophobicity of Bigelow ((1967) J. Theoret. Biol. 16, 187--211) that was calculated from the total amino acid composition of each protein. The interfacial tensions at the 0.2% protein/corn oil interface revealed negative correlations with the effective hydrophobicities determined by both methods indicating lower interfacial tensions with more hydrophobic proteins.     

A study of D‐lactate and extracellular methylglyoxal production in lactate Re‐Utilizing CHO cultures

In large‐scale mammalian cell culture, the key toxic by‐products assessed and monitored are lactate and ammonia. Often no distinction between the two isoforms of lactate is made. Here, we present profiles of both D ‐ and L ‐lactate. D ‐Lactate is the end molecule of the methylglyoxal pathway. D ‐Lactate unlike L ‐lactate is not re‐utilized, and although during normal culture time frames it represents one‐tenth of total lactate, during lactate re‐use it represents nearly 35%. This indicates significant carbon flow through pathways not associated with primary metabolites. We have observed that the behavior of D ‐lactate is radically different from that of L ‐lactate with the level of one isoform changing, whilst the concentration of the other remains constant. This is an example of an alternate carbon flow pathway containing metabolic intermediates that may potentially have a detrimental effect on cells. The activity of the methylglyoxal pathway when measured as a proportion of glucose consumption in this study far exceeds any previously reported. This highlights the potential importance of “non‐primary” metabolisms to long lifespan mammalian fermentation practices. Biotechnol. Bioeng. 2010;107: 182–189. © 2010 Wiley Periodicals, Inc.     

Effect of pH and loading manner on the start-up period of peat biofilter degrading xylene and toluene mixture

Laboratory-scale biofilters packed with a mixture of peat, bark and wood were used for xylene and toluene removal from waste air. Two kinds of peat, which differed in the resulting pH of the leachate, were chosen for degradation of the pollutants by a mixed culture. Using peat with the lower pH value, the feasibility of single and multiple pollutant loading during the start-up period and augmentation withPseudomonas putida strains were characterized. The lower pH value of the bed resulted in higher efficiency of toluene degradation from the mixture of pollutants. At higher pH values better degradation of both pollutants was achieved. Regarding the manner of loading during the start-up period, the best results were obtained using toluene as a single pollutant in the initial phase of operation.Pseudomonas strains demonstrated a high ability to degrade both pollutants; more efficient degradation for xylene than for toluene was observed at high loading rates.