Nitrifikationshämning i tvätteriavloppsvatten

The nitrification process is known to be the most sensitive link in biological nitrogen removal used in many wastewater treatment plants. Many different inhibitory substances can disturb these sensitive bacteria and in that way cause reduced nitrogen removal. The aim of this study was to investigate the nitrification inhibition in a laundry wastewater before and after internal chemical treatment. In addition the used detergents, containing alcohol ethoxylates, and also the bleaching agent at the facility were tested for nitrification inhibition in order to investigate their possible contribution. Furthermore activated carbon was investigated as a method to decrease inhibitory substances in the wastewater. The results confirm that the facility do have problems with to high levels of nitrification inhibition. The results also reveal that there is just a small decrease in nitrification inhibition in the effluent compared to the influent, indicating that the chemical treatment is not sufficient in removing these inhibitory substances in the wastewater. This tests also show that both the bleaching agent and detergents containing alcohol ethoxylates can be inhibitory to the nitrification process. It was also found that activated carbon can be utilized to remove the inhibiting substances from the wastewate

Empty substrate integrated waveguide technology for E plane high-frequency and high-performance circuits

Substrate integrated circuits (SIC) have attracted much attention in the last years because of their great potential of low cost, easy manufacturing, integration in a circuit board, and higher-quality factor than planar circuits. A first suite of SIC where the waves propagate through dielectric have been first developed, based on the well-known substrate integrated waveguide (SIW) and related technological implementations. One step further has been made with a new suite of empty substrate integrated waveguides, where the waves propagate through air, thus reducing the associated losses. This is the case of the empty substrate integrated waveguide (ESIW) or the air-filled substrate integrated waveguide (air-filled SIW). However, all these SIC are H plane structures, so classical H plane solutions in rectangular waveguides have already been mapped to most of these new SIC. In this paper a novel E plane empty substrate integrated waveguide (ESIW-E) is presented. This structure allows to easily map classical E plane solutions in rectangular waveguide to this new substrate integrated solution. It is similar to the ESIW, although more layers are needed to build the structure. A wideband transition (covering the frequency range between 33 GHz and 50 GHz) from microstrip to ESIW-E is designed and manufactured. Measurements are successfully compared with simulation, proving the validity of this new SIC. A broadband high-frequency phase shifter (for operation from 35 GHz to 47 GHz) is successfully implemented in ESIW-E, thus proving the good performance of this new SIC in a practical application.This work was supported by the Ministerio de Economía y Competitividad, Spanish Goverment, under research projects TEC2013-47037-C5-3-R, TEC2013-47037-C5-1-R, AYA2013-49759-EXP, and CSD2010-00064

Genome evolution and plasticity of <em>Serratia marcescens</em>:an important multidrug resistant nosocomial pathogen

Serratia marcescens is an important nosocomial pathogen that can cause an array of infections, most notably of the urinary tract and bloodstream. Naturally, it is found in many environmental niches, and is capable of infecting plants and animals. The emergence and spread of multidrug-resistant strains producing extended-spectrum or metallo beta-lactamases now pose a threat to public health worldwide. Here we report the complete genome sequences of two carefully selected S. marcescens strains, a multidrug-resistant clinical isolate (strain SM39) and an insect isolate (strain Db11). Our comparative analyses reveal the core genome of S. marcescens and define the potential metabolic capacity, virulence, and multidrug resistance of this species. We show a remarkable intraspecies genetic diversity, both at the sequence level and with regards genome flexibility, which may reflect the diversity of niches inhabited by members of this species. A broader analysis with other Serratia species identifies a set of approximately 3,000 genes that characterize the genus. Within this apparent genetic diversity, we identified many genes implicated in the high virulence potential and antibiotic resistance of SM39, including the metallo beta-lactamase and multiple other drug resistance determinants carried on plasmid pSMC1. We further show that pSMC1 is most closely related to plasmids circulating in Pseudomonas species. Our data will provide a valuable basis for future studies on S. marcescens and new insights into the genetic mechanisms that underlie the emergence of pathogens highly resistant to multiple antimicrobial agents

Exploring consumers perceived risk and trust for mobile shopping: A theoretical framework and empirical study

Despite mobile device usage being at an all-time high, their utilisation for mobile shopping activities is inherently low. The study, first, identifies prominent areas of academic concern and examines areas requiring further insight. A theoretical model is developed to examine multi-faceted risk and trust effects on consumer adoption intention. Empirical results demonstrate several trust and risk perceptions as having varying effects on consumers’ m-shopping intention. Inclusion of age and gender reveals discrepancies among positive and negative influencers of intention. Results contribute to theoretical and practical understandings surrounding deterrents of intention and potential risk-reduction mechanisms for future considerations

Traumatic brain injury and peripheral immune suppression: primer and prospectus

Nosocomial infections are a common occurrence in patients following traumatic brain injury (TBI) and are associated with an increased risk of mortality, longer length of hospital stay and poor neurological outcome. Systemic immune suppression arising as a direct result of injury to the central nervous system (CNS) is considered to be primarily responsible for this increased incidence of infection, a view strengthened by recent studies that have reported novel changes in the composition and function of the innate and adaptive arms of the immune system post TBI. However, our knowledge of the mechanisms that underlie TBI-induced immune suppression is equivocal at best. Here, after summarising our current understanding of the impact of TBI on peripheral immunity and discussing CNS-mediated regulation of immune function, we propose roles for a series of novel mechanisms in driving the immune suppression that is observed post TBI. These mechanisms, which have never been considered before in the context of TBI-induced immune paresis include the CNS-driven emergence into the circulation of myeloid derived suppressor cells and suppressive neutrophil subsets, and the release from injured tissue of nuclear and mitochondria-derived damage associated molecular patterns. Moreover, in an effort to further our understanding of the mechanisms that underlie TBI-induced changes in immunity, we pose throughout the review a series of questions, which if answered would address a number of key issues such as establishing whether manipulating peripheral immune function has potential as a future therapeutic strategy by which to treat and/or prevent infections in the hospitalised TBI patient

En jämförelsestudie av värmeväxlare : Värmeöverföring för värmeväxlare i korrosiva miljöer

Det finns stora vinningar att göra inom både transport- och industrisektorn genom att effektivisera materialanvändningen i produkter. Denna vinning återfinns i både materialkostnader och energieffektivisering. Scandymet AB är ett företag som tillverkar värmeväxlare och elektriska doppvärmare för ytbehandlingsindustrin. Denna rapport syftar till att utvärdera hur väl ett kalkylark som används som underlag för dimensionering av värmeväxlare hos företaget stämmer överens med verkligheten. En testrigg har därför konstruerats för att undersöka kalkylarkets validitet gällande temperaturer under 46 grader Celsius. I rapporten redovisas resultaten av tester på fyra olika värmeväxlare och resultaten har jämförts med företagets kalkylark. Undersökningarna visar att två av dessa värmeväxlare är överdimensionerade och två värmeväxlare stämde väl överens med kalkylarket. I samtliga tester används vatten som media, men då Scandymet AB värmeväxlares huvudsakliga användningsområde är korrosiva vätskor dras slutsatsen att fler undersökningar med andra fluider skulle behövas för att ytterligare fördjupa kunskapen inom värmeväxlarnas korrekta dimensionering.There are huge gains in both the transport and industry sectors by making material use more efficient in products. This gain is found in both material costs and energy efficiency. Scandymet AB is a company that manufactures heat exchanger and electric immersion heaters for the surface treatment industry. This report aims to evaluate how well a spreadsheet used as basis for the dimensioning of heat exchangers at the company is consistent with reality. A test rig has therefore been designed and constructed to investigate the validity of the spreadsheet. The report presents the results of tests on four different heat exchangers and the results have been compared with the company’s spreadsheet. In all tests water has been used as the media to be heated, but since Scandymet AB’s heat exchanger’s main application is corrosive liquids, therefore I consider that a deeper investigation with additional fluids would be necessary to further deepen the knowledge in the area