Automated iterative MS/MS acquisition: a tool for improving efficiency of protein identification using a LC-MALDI MS workflow

We have developed an information-dependent, iterative MS/MS acquisition (IMMA) tool for improving MS/MS efficiency, increasing proteome coverage, and shortening analysis time for high-throughput proteomics applications based on the LC-MALDI MS/MS platform. The underlying principle of IMMA is to limit MS/MS analyses to a subset of molecular ions that are likely to identify a maximum number of proteins. IMMA reduces redundancy of MS/MS analyses by excluding from the precursor ion peak lists proteotypic peptides derived from the already identified proteins and uses a retention time prediction algorithm to limit the degree of false exclusions. It also increases the utilization rate of MS/MS spectra by removing "low value" unidentifiable targets like nonpeptides and peptides carrying large loads of modifications, which are flagged by their "nonpeptide" excess-to-nominal mass ratios. For some samples, IMMA increases the number of identified proteins by ～20-40% when compared to the data dependent methods. IMMA terminates an MS/MS run at the operator-defined point when "costs" (e.g., time of analysis) start to overrun "benefits" (e.g., number of identified proteins), without prior knowledge of sample contents and complexity. To facilitate analysis of closely related samples, IMMA's inclusion list functionality is currently under development.     

Evaluation of sensory attributes of coffee brews from robusta coffee roasted under different conditions

Robusta coffee beans with a different initial moisture of 5, 7.5 and 10% were convectively roasted at 230 °C, microwaved at 700 W, and roasted by the coupled convective-microwave method. Sensory attributes of brews prepared from these coffee samples were evaluated. Final temperature of microwaved coffee beans was lower than that of the beans processed by the two other methods, which resulted in a higher content of volatile aroma compounds and a lesser degree of charring of their surface. Lower initial humidity of coffee beans shortened the time of roasting. However, the aroma developed upon roasting of the moistest beans was the most intense and pleasant. Modification of roasting conditions increased shifting of the overall acceptability of coffee infusions by 2 points in a 10-point hedonic scale, which implies that, if roasting conditions are adequate to the type of coffee, its sensory characteristics can be improved. Thus, optimization of roasting parameters can increase the share of robusta in well-accepted commercial coffee blends, a convenient fact because of the significant difference in price between the latter and arabica coffee.     

Purulent mediastinitis

The aspects of acute purulent mediastinitis (APM) have been reported on the basis of the analysis of 14 cases treated in the last 5 years. The most frequent causes of APM were the complications after surgery on esophagus ad trachea (10 cases). The other group included patients operated on by sternotomy. Three patients survived. In both of them diagnosis was established within 12 hours from the beginning of APM and early re-thoracotomy was performed. The rest of the patients died because of sepsis and multiply organ failure (MOF). The conclusion is that only early diagnosis as well as aggressive surgical treatment give a chance to save life in such a dangerous severe complication.     

Large-scale multimedia content delivery over optical networks for interactive TV services

iTVP is a system built for delivery of live TV programming, video-on-demand and audio-on-demand with interactive access over IP networks. It has a nationwide range and is designed to provide service to a high number of concurrent users. Hence, scalability is one of the most important issues. In this paper we described how scalability is achieved in a two-level hierarchical architecture of the delivery system. We present the principles of content caching mechanisms and the management of the resulting distributed content repository. The system is implemented and currently operates in a test installation. Although the range of the test system operations is limited, as far as the number of users and the size of the content repository is concerned, the experience gained with iTVP so far provides an insight into the expected prototype performance. We present a system performance evaluation and describe the experience gained during the iGrid demonstration.     

Optimization of an industrial DC magnetron sputtering process for graded composition solar thermal absorbing layer

Optimization of an industrial DC magnetron sputtering process for thin graded index coatings for solar thermal absorbers is reported. The optimization concerned the main processing parameters: sputtering power, argon flow, oxygen flow, and system set-up for graded control. The purpose of the optimization was to achieve a surface with efficient solar-thermal energy conversion based on the concept graded index coating, using a metal-dielectric composite coating of nickel–nickel oxide with a continuous change in composition through the film depth profile. It was found that the optimization of the materials composition could be controlled by one parameter related to the sputtering process, the relative oxygen flow RO, defined as the ratio of applied oxygen flow to the critical oxygen flow. For optimized sputtering conditions a solar absorptance of 0.92 was obtained for a single graded index coating on aluminum for RO value of 0.8. From the materials characterization it was found that this gave a graded index coating of two thick sub-layers, a top layer of nano-sized nickel oxide grains and a base layer of nano-size metallic nickel grains with a very thin interface of a mixture of nickel and nickel oxide that was almost amorphous.     

Monitoring pH-dependent conformational changes in aqueous solutions of poly(methacrylic acid)-b-polydimethylsiloxane copolymer based on fluorescence spectra of pyrene and 1,3-bis(1-pyrenyl)propane

Aqueous solutions of poly(methacrylic acid)-b-polydimethylsiloxane copolymer (PMA-b-PDMS), and reference solutions of PMA homopolymer, were studied as a function of pH using fluorescent probes: pyrene (P) and 1,3-bis(1-pyrenyl)propane (P3P). In both polymers the conformational transition of PMA chains at pH>5 was reflected in the sharp increase of the intensity ratio of the first to the third vibronic band in emission spectra of P; an excimer emission appeared for P3P, as well as for P if the probe concentration was higher than its solubility limit in water. The excimer to monomer intensity ratio of both probes is a sensitive indicator of the conformational transitions of polymer chains, but P3P is significantly more sensitive compared to pyrene. The data clearly indicated that the presence of PDMS blocks markedly facilitated the transition, even though the ratio of dimethylsiloxane to methacrylic acid units in the copolymer was low, 1:34. The absence of the P3P excimer emission at pH≈3 was rationalized by assuming that clustering of sections of PMA chains around pyrene moieties imposes an extended conformation of the probe molecule.     

Application of Porous Glasses in Ophthalmic Prosthetic Repair

The ophthalmic prosthetic materials besides their necessary cosmetic view should be biologically inert. Silica porous glasses can be fabricated to satisfy the cosmetic requirements while their pores can be filled with medicines that would help to avoid complications when contacting the biological tissues. In this work the ability of different silica porous glasses to support a necessary level of the medicine around itself for long periods of time was studied. Hentamicini sulphate antibiotic was used as the biologically active substance while vitamin B₆ was employed as the nutrient. The concentration of the above substances in the normal saline solution that simulated the lachrymal liquid was controlled by the luminescent technique. It was demonstrated that the silica porous glass that was obtained by phase separation at 490°C without subsequent removal of the residual silica gel supported the necessary level of medicines around itself for the longest period of time.     

Untersuchungen über die Dehnbarkeit von Leimfugen

The decline of a preceding compression and the swelling during moistening of pine sapwood samples were investigated. The deformations occurring simultaneously on the samples were impeded by introducing in parallel direction different glue lines or glue layers. It was found that only glue lines which had been hardened under pressure in the wood tissue had tensile strength enough to markedly delay and finally reduce the deformations. Glue layers, however, which had been hardened on the surface of the wood without pressure did not show such a tensile strength and did not exert any significant influence on the deformations observed.     

The phenomena of the interaction of Nd3+-glass laser light with 6H13 alloy steel

The variation in the physical and chemical structure of the 6H13 alloy steel irradiated by laser light have been investigated. The phenomena of the capillary waves within the power density range (4.3×10⁹<P<13.8×10⁹) watt/m² have been observed and the hydrodynamic parameters of alloy steel have been determinated. The nature of the laser light interaction with metal is discussed in electronmicroscopy and X-rays analysis terms.     

Änderungen der Fugenfläche und ihr Einfluß auf die Scherfestigkeit von Leimverbindungen

Ohne Zusammenfassung