The yin-yang driving urinary tract infection and how proteomics can enhance research,diagnostics, and treatment

Bacterial urinary tract infections (UTIs) afflict millions of people worldwide both in the community and the hospital setting. The onset, duration, and severity of infection depend on the characteristics of the invading pathogen (yin), as well as the immune response elicited by the infected individual (yang). Uropathogenic Escherichia coli (UPEC) account for the majority of UTIs, and extensive investigations by many scientific groups have elucidated an elaborate pathogenic UPEC life cycle, involving the occupation of extracellular and intracellular niches and the expression of an arsenal of virulence factors that facilitate niche occupation. This review will summarize the current knowledge on UPEC pathogenesis; the host immune responses elicited to combat infection; and it will describe proteomics approaches used to understand UPEC pathogenesis, as well as drive diagnostics and treatment options. Finally, new strategies are highlighted that could be applied toward furthering our knowledge regarding host-bacterial interactions during UTI.     

Probleme bei Planung und Betrieb von Absetzbecken für Straßenabwässer

Sedimentation basins are incorporated into runoff infiltration systems and serve as a retention system, in which the sedimentation of particles occurs as a result of gravitational force. The effectiveness of sedimentation basins in terms of removing particles is highly dependent on design parameters such as their dimensions and drainage times. To evaluate the flow distribution within sedimentation basins, a conceptual model was developed using a tracer and compared to the actual condition at the treatment system. Here, a significant difference in the height of the connecting tube between settling basin and filter basin was found. This leads to a drying out of the basin, which significantly affects the flow rates and hence the sedimentation there. Based on a model experiment with colour tracer, the flow paths were visually represented in the basin, and both the concrete variant and the effects of internal structures were considered. It was found that the incorporation of a baffle led to an improved utilization of the basin, and to water being retained for longer times. Due to the lower flow rate and these longer times, fine and medium-sized sediments could be easily settled. In a field study, the performance of a sedimentation basin for the removal of particles was evaluated based on the influent and effluent concentrations of total suspended solids (TSS). The street runoff treatment plant was monitored for one year and results showed that there was no particle accumulation in the sedimentation basin (there was no permanent retention of the particle loads). The mean TSS concentrations were 89 mg/L at the inlet of the sedimentation basin and 94 mg/L at the end of the settling tank, respectively. The structural design and operation of the system showed higher flow and turbulent flow conditions in the sedimentation basin, in which settlement of fine and medium sized particles was very low; as a result, the soil filter basin was loaded with runoff particles. Thus the particulate matter had to be removed either on the surface of the filter basin or within the porous space of the filter. The build-up of such particles can result in a significant increase of head loss due to clogging; therefore, filters must be maintained by removing the accumulated particles on a regular basis.     

The application of uncertainty measures in the training and evaluation of supervised classifiers

The production of thematic maps from remotely sensed images requires the application of classification methods. A great variety of classifiers are available, producing frequently considerably different results. Therefore, the automatic extraction of thematic information requires the choice of the most appropriate classifier for each application. One of the main objectives of the research described in this article is to evaluate the performance of supervised classifiers using the information provided by the application of uncertainty measures to the testing sets, instead of statistical accuracy indices. The second main objective is to show that the information provided by the uncertainty measures for the training set may be used to assess and redefine the sample sites included in this set, in order to improve the classification results. To achieve the proposed objectives, two supervised classifiers, one probabilistic and another fuzzy, were applied to a very high spatial resolution (VHSR) image. The results show that similar conclusions on the classifiers’ performance are obtained with the uncertainty measures and the traditional accuracy indices obtained from error matrices. It is also shown that the redefinition of the training set based on the information provided by the uncertainty measures may generate more accurate outputs.     

A complexity reduction approach to detectability of switching systems

In this article, we address detectability for the class of linear switching systems. We focus on some hybrid state-space decompositions of the original switching system based on hybrid invariant subspaces, which yield a complexity reduction in checking detectability. We show that the reduced system extracted from the original system is the minimal bisimilar switching system associated with it. An example is also included which shows the applicability and benefits of the proposed approach.     

Organometallic Pt(II) containing polymer as silver protection against sulfide tarnishing

In this work, the use of a film of an organometallic polymer, namely Pt‐DEBP, has been tested for the selective capture of sulfides with the aim of protecting silver object. Ag foils were exposed to different environmental conditions in the presence of Pt‐DEBP films. Scanning electron microscopy, energy dispersive spectrometry, and colorimetric studies allowed to assess that the polymeric layer selectively captures H₂S, preventing the tarnishing of the silver substrate over a period at least of 2 months, without any manipulation of the sample. This approach open new perspectives for the prevention of aging effects on silver objects of artistic interest, for which cleaning or coating procedures should be avoid. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Apparent Molar Volumes of N,N – Disubstituted Monoamides: A Convenient Tool to Interpret Iron(Iii) Extraction Profiles from Hydrochloric Acid Solutions

New iron(III) extraction data involving two N,N-disubstituted monoamides, N-ethyl-N-phenyloctanamide (EPHOA) and N-ethyl-N-cyclohexyloctanamide (ECHOA), from hydrochloric acid media, are presented and discussed. These, and earlier results obtained with other similar N,N-disubstituted monoamides, are interpreted in this work through their apparent molar volumes in 1,2-dichloroethane, and all the information is being used to screen for solute-solute and solute-diluent interactions. The results collected help to understand why N-cyclohexyl monoamides are generally more efficient than their N-phenyl analogues as liquid-liquid extractants for iron(III) from 3 to 5 M hydrochloric acid solutions, and clearly denote that N-phenyl monoamides are essentially monomeric whereas N-cyclohexyl monoamide derivatives have a tendency to aggregate in the organic solution.     

Antioxidant and Prooxidant Activity Behavior of Phospholipids in Stripped Soybean Oil-in-Water Emulsions

Phospholipids have been reported to inhibit lipid oxidation in bulk oils, but very little is known about their influence on oxidation in oil-in-water emulsions. In the present study, the impact of 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) on lipid oxidation was studied in 1% stripped soybean oil-in-water (O/W) emulsions as a function of DOPC concentration and pH (3 and 7). At pH 7.0, DOPC inhibited lipid oxidation in O/W emulsions, while DOPC was prooxidative at pH 3.0. DOPC did not affect emulsion droplet charge or size at either pH 3.0 or 7.0. The antioxidant activity at pH 7.0 was observed in a series of phospholipids (PL) that varied in fatty acid unsaturation level and chain length as well as type of phosphate head group. Overall, phosphatidylcholine with either oleic or palmitic acid were the most effective at inhibiting lipid hydroperoxide and hexanal formation of all of the PL tested. Antioxidant mechanism of PL could not be ascribed to their ability to decompose lipid hydroperoxides. It might be possible that, at pH 7.0, the PL antioxidant activity is related to their ability to form structures within the lipid phase of the emulsions droplets or to chelate metals.     

Grafting of titanium dioxide microspheres with a temperature‐responsive polymer via surface‐initiated atom transfer radical polymerization without the use of silane coupling agents

Titania microspheres with narrow size distribution and diameters of about 1 µm were prepared and subsequently functionalized using surface‐initiated atom transfer radical polymerization (ATRP) of N‐isopropylacrylamide. The ATRP initiator was immobilized on the particle surface via acylation of surface hydroxyl groups with α‐bromoisobutyryl bromide. Subsequently, an established ATRP reaction system was used for the preparation of titania surface‐grafted poly(N‐isopropylacrylamide) (PNiPAAm). Characterization was performed with electron microscopies, X‐ray diffraction, infrared spectroscopy and dynamic light scattering. It was found that the particle size in aqueous dispersions changed reversibly with temperature as expected for a shell of PNiPAAm, a polymer with a lower critical solution temperature at 32 °C. This confirmed the successful preparation of functional, stimuli‐responsive TiO₂ microparticles via a straightforward controlled surface‐initiated polymerization method.