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Phage therapy could offer a safe and effective alternative to antibiotic treatment of infections caused by Gram-positive bacterium Staphylococcus aureus that have emerged as a significant threat in hospital and community environment and is attracting growing interest among clinicians. The legislation process of approving the phage therapeutics by pharmaceutical authorities requires rapid analytical techniques for assessment of phage activity. Here, we present a three-step method for on-line monitoring the phage effect on bacterial cells dynamically adhered from microliter volumes of high conductivity matrix onto the inner surface of fused silica capillary with a part etched with supercritical water. Phage K1/420 particles of the Kayvirus genus generated by propagation on the host S. aureus cells together with the uninfected cells were concentrated, separated and detected using capillary electrophoretic methods. The phage interactions with selected S. aureus strains exhibiting differences in phage susceptibility were compared. The method allowed determination of the phage burst size and time of phage latent period in analyzed strains. Apart from enumeration of bacteriophages by the plaque assays, the proposed method is suitable for phage activity testing.

Abstract Atmospheric infrasound of frequencies 0.1–4 Hz observed in Central Europe during convective storms on 9–10 July 2011 from 21:00 to 02:57 UT was analysed. Azimuth of signal arrival followed positions of the convective storms passing over the region of measurements from south-west to north-east. Significant variations in azimuths of signal arrival (up to 105°) occurred periodically between 21:30 and 23:00 UT, at the time of maximum development of convective storms. Sprites (discharges in the mesosphere) seem to be potential sources of these infrasound signals. Stable infrasound arrivals were observed between 02:00 and 02:57 UT from direction where abating convective storms were located.

We propose a computational model to study (the evolution of) post-secondary education. “Consumers” who differ in quality shop around for desirable colleges or universities. “Firms” that differ in quality signal the availability of their services to desirable students. As long as they have capacity, colleges and universities make offers to students, who apply and qualify. Our model generalizes an earlier literature (namely, Vriend 1995) in an important dimension: quality, the model confirms key predictions of an analytical model that we also supply, and the model allows us to systematically explore the emergence of macro regularities and the consequences of various strategies that sellers might try. We supply three such exercises. In our baseline treatment we establish the dynamics and asymptotics of our generalized matching model. In the second treatment we study the consequences of opportunistic behavior of firms and thus demonstrate the usefulness of our computational laboratory for the analysis of this or similar questions (e.g., the problem of early admission). In the third treatment we equip some firms with economies of scale. This variant of our matching model is motivated by the entry of for-profit providers into low-quality segments of post-secondary education in the USA and by empirical evidence that, while traditional nonprofit or state-supported providers of higher education do not have significant economies of scale, the new breed of for-profit providers seems to capture economies in core functions such as curricular design, advertising, informational infrastructure, and regulatory compliance. Our computational results suggest that this new breed of providers is likely to continue to move up the quality ladder, albeit not necessarily all the way up to the top.

For the purposes of trace analysis of 1,4-androstadiene-3,17-dione (ADD), 1,4-androstadiene-3-one-17β-ol (Boldenone) and 17-β-estradiol in water, waste water, soil and for the further phytosterols transformation studies the enolisation-silylation reaction was studied using MSTFA and BSTFA with different catalysts as derivatization reagents. The different reaction conditions and stability of the products was also studied using GC-MS technique.

The paper presents a case study in an industrially important application domain the optimization of catalytic materials. Though evolutionary algorithms are the by far most frequent approach to optimization tasks in that domain, they are challenged by mixing continuous and discrete variables, and especially by a large number of constraints. The paper describes the various kinds of encountered constraints, and explains constraint handling in GENACAT, one of evolutionary optimization systems developed specifically for catalyst optimization. In particular, it is shown that the interplay between cardinality constraints and linear equality and inequality constraints allows GENACAT to efficienlty determine the set of feasible solutions, and to split the original optimization task into a sequence of discrete and continuous optimization. Finally, the genetic operations employed in the discrete optimization are sketched, among which crossover is based on an assumption about the importance of the choice of sets of continuous variables in the cardinality constraints.

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Microalgae are a known source of proteins, prebiotics, lipids, small molecules, anti-oxidants and bioactives with health benefits that can be harnessed for the development of functional foods, feeds, cosmeceuticals and pharmaceuticals. This review collates information on the supply, processing costs, target markets and value of microalgae, as well as microalgal proteins, lipids, vitamins and minerals. It discusses the potential impact that microalgae could have on global food and feed supply and highlights gaps that exist with regards to the use of microalgal proteins and ingredients as foods and supplements.

To have more detailed information about rock massif behaviour, distributed control and measurement network for evaluation of hydrologic, geomechanical and other parameters has been built up in the medieval Jeroným Mine from the first half of 2006. Instrumentation is generally based on commercial control kit and sensors. This network is integrated to the seismic recording apparatus equipped by data transmission via GSM network to registration centre in Ostrava. Completely monitoring system is performed as modular to have possibility to change configuration of this system.