Integration of binding peptide selection and multifunctional particles as tool-box for capture of soluble proteins in serum

In this paper, we report on a general approach for the detection of a specific tumoural biomarker directly in serum. Such detection is made possible using a protein-binding peptide selected through an improved phage display technique and then conjugated to engineered microparticles (MPs). Protein biomarkers represent an unlimited source of information for non-invasive diagnostic and prognostic tests; MP-based assays are becoming largely used in manipulation of soluble biomarkers, but their direct use in serum is hampered by the complex biomolecular environment. Our technique overcomes the current limitations as it produces a selective MP—engineered with an antifouling layer—that ‘captures’ the relevant protein staying impervious to the background. Our system succeeds in fishing-out the human tumour necrosis factor alpha directly in serum with a high selectivity degree. Our method could have great impact in soluble protein manipulation and detection for a wide variety of diagnostic applications.     

Modeling survival of high hydrostatic pressure treated stationary- and exponential-phase Listeria innocua cells

High Hydrostatic Pressure (HHP) inactivation (325–400 MPa; 0–20 min; maximum temperature 30 °C) of cells of Listeria innocua CECT 910 was studied in two different growth phases (exponential and stationary), and the corresponding survival curves were obtained for each case. The curves were fitted to two nonlinear models, the modified Gompertz equation and the Baranyi model. The kinetic constants calculated for both models, µ_max and k_max, indicated that cells in exponential growth phase were more sensitive to pressure than those in stationary phase. Both mathematical models were suitable for describing L. innocua HHP survival curves, rendering kinetic constants that increased with increasing pressure. When considering the experimental models validation, both Gompertz and Baranyi predicted in a similar way, however Baranyi had slightly lower A_f (Accuracy factor) and B_f (Bias factor) values, which indicated better prediction values. In summary, both mathematical models were perfectly valid for describing L. innocua inactivation kinetics under HHP treatment.Industrial relevanceThe mathematical models for inactivation and growth of microorganisms are the foundation of predictive microbiology and are used in risk assessments procedures as part of the food safety management system. Besides, these models together with those applied to inactivation of enzymes and destruction of quality factors are essential to optimize processes and thus to lay the foundations for industrial processing. It is therefore necessary to identify generally applicable kinetic models that will produce primary and secondary kinetic parameters and are statistically reliable as a key tool to predict the behaviour of microorganisms, enzymes and quality factors after processing.     

Influence of vitrified bond structure on radial wear of cBN grinding wheels

This paper presents the results of research concerning the radial wear of super hard grinding wheels in the process of internal grinding of bearing rings. The new-developed grinding wheel is designed for bonding the abrasive grains of submicrocrystalline boron nitride using a glass–ceramic bond. This grinding wheel is compared to cBN grinding wheels composed from ceramic bonding systems, currently having application in industry. A crystalline phase from a group of single-diagonal pyroxenes of an XYSi₂O₆ type was generated at the glass–ceramic bond from a CaO–MgO–Al₂O₃–B₂O₃–SiO₂ system. An influence of the presence of this phase on the bond fracture toughness coefficient K_Ic and the elastic modulus E of cBN grinding wheels was examined. Compared to grinding wheels comprising the commercial bond from a Na₂O–K₂O–Al₂O₃–B₂O₃–SiO₂ system, the microcrystalline structure of the new-developed bond limits the range of its fragmentation in the process of grinding. It exerts a marked influence on the formation of different roughness profiles on the wheel working surface and the wear resistance, compared to a grinding wheel composed from a commercial bond.     

Modeling the formation of precursors of dioxins during combustion of woody fuel volatiles

The emissions of polychlorinated-p-dibenzodioxins (PCDD) and dibenzofurans (PCDF) from waste combustion show a close correlation with the emissions of chlorinated benzenes or phenols, which could therefore be used as indicators for easier, faster and cheaper prediction of the potential dioxin emission levels. Using contemporary analytical methods, the emissions of, e.g. monochlorobenzene can be measured on-line and predictions could be made via a suitable mathematical model describing the link between these precursors and dioxins. Modeling the formation of the precursors could therefore provide an indirect possibility for the prediction of dioxins' formation and subsequent optimization of the combustion process characteristics.A detailed combustion mechanism consisting of 3678 gas-phase reactions between 755 species including chlorine chemistry has been developed. The influence of temperature, reaction time, equivalence ratio and chlorine concentration on monochlorobenzene and monochlorophenols formation was tested for batch and well-stirred reactors. The impact of good mixing conditions, appropriate level of oxygen, chlorine contents and temperature regime on the formation of precursors of dioxins is emphasized.     

Testing high resolution ΣΔ ADC's by using the quantizer input as test access

A new solution to improve the testability of high resolution ΣΔ Analogue to Digital Converters (ΣΔ ADC's) using the quantizer input as test node is described. The theoretical basis for the technique is discussed and results from high level simulations for a 16 bit, fourth order, audio ADC are presented. The analysis demonstrates the potential to reduce the computational effort associated with test response analysis versus conventional techniques. If only SNR, THD and gain of the ΣΔ ADC are evaluated with the new proposed method the test time is already reduced by 20%.     

An analytical model of information dissemination for a gossip-based protocol

We develop an analytical model of information dissemination for a gossiping protocol that combines both pull and push approaches. With this model we analyse how fast an item is replicated through a network, and how fast the item covers the network. We also determine the optimal size of the exchange buffer, to obtain fast replication. Our results are confirmed by large-scale simulation experiments.     

Effect of hydrophilic–hydrophobic balance on biocompatibility of poly(methyl methacrylate) (PMMA)–hydroxyapatite (HA) composites

The purpose of this study is to put in evidence the correlation between hydrophilic/hydrophobic balance and biocompatibility of PMMA–HA composites, in order to select the best composites for futures clinical applications. For this purpose, PMMA–HA cements with different compositions were prepared and static contact angle measurements, water absorption and gingival fibroblasts cell culture were performed and discussed.