Three-dimensional stratification of bacterial biofilm populations in a moving bed biofilm reactor for nitritation-anammox.

Moving bed biofilm reactors (MBBRs) are increasingly used for nitrogen removal with nitritation-anaerobic ammonium oxidation (anammox) processes in wastewater treatment. Carriers provide protected surfaces where ammonia oxidizing bacteria (AOB) and anammox bacteria form complex biofilms. However, the knowledge about the organization of microbial communities in MBBR biofilms is sparse. We used new cryosectioning and imaging methods for fluorescence in situ hybridization (FISH) to study the structure of biofilms retrieved from carriers in a nitritation-anammox MBBR. The dimensions of the carrier compartments and the biofilm cryosections after FISH showed good correlation, indicating little disturbance of biofilm samples by the treatment. FISH showed that Nitrosomonas europaea/eutropha-related cells dominated the AOB and Candidatus Brocadia fulgida-related cells dominated the anammox guild. New carriers were initially colonized by AOB, followed by anammox bacteria proliferating in the deeper biofilm layers, probably in anaerobic microhabitats created by AOB activity. Mature biofilms showed a pronounced three-dimensional stratification where AOB dominated closer to the biofilm-water interface, whereas anammox were dominant deeper into the carrier space and towards the walls. Our results suggest that current mathematical models may be oversimplifying these three-dimensional systems and unless the multidimensionality of these systems is considered, models may result in suboptimal design of MBBR carriers

Collection of Aerosolized Human Cytokines Using Teflon® Filters

Background: Collection of exhaled breath samples for the analysis of inflammatory biomarkers is an important area of research aimed at improving our ability to diagnose, treat and understand the mechanisms of chronic pulmonary disease. Current collection methods based on condensation of water vapor from exhaled breath yield biomarker levels at or near the detection limits of immunoassays contributing to problems with reproducibility and validity of biomarker measurements. In this study, we compare the collection efficiency of two aerosol-to-liquid sampling devices to a filter-based collection method for recovery of dilute laboratory generated aerosols of human cytokines so as to identify potential alternatives to exhaled breath condensate collection. Methodology/Principal Findings: Two aerosol-to-liquid sampling devices, the SKC® Biosampler and Omni 3000™, as well as Teflon® filters were used to collect aerosols of human cytokines generated using a HEART nebulizer and single-pass aerosol chamber setup in order to compare the collection efficiencies of these sampling methods. Additionally, methods for the use of Teflon® filters to collect and measure cytokines recovered from aerosols were developed and evaluated through use of a high-sensitivity multiplex immunoassay. Our results show successful collection of cytokines from pg/m3 aerosol concentrations using Teflon® filters and measurement of cytokine levels in the sub-picogram/mL concentration range using a multiplex immunoassay with sampling times less than 30 minutes. Significant degradation of cytokines was observed due to storage of cytokines in concentrated filter extract solutions as compared to storage of dry filters. Conclusions: Use of filter collection methods resulted in significantly higher efficiency of collection than the two aerosol-to-liquid samplers evaluated in our study. The results of this study provide the foundation for a potential new technique to evaluate biomarkers of inflammation in exhaled breath samples

Evaluation of air oxidized PAPC: A multi laboratory study by LC-MS/MS

Oxidized LDL (oxLDL) has been shown to play a crucial role in the onset and development of cardiovascular disorders. The study of oxLDL, as an initiator of inflammatory cascades, led to the discovery of a variety of oxidized phospholipids (oxPLs) responsible for pro-inflammatory actions. Oxidized 1-palmitoyl-2-arachidonoyl-sn-glycero-3-phosphocholine (PAPC) is frequently used by the scientific community as a representative oxPL mixture to study the biological effects of oxidized lipids, due to the high abundance of PAPC in human tissues and the biological activities of oxidized arachidonic acids derivatives. Most studies focusing on oxPAPC effects rely on in-house prepared mixtures of oxidized species obtained by exposing PAPC to air oxidation. Here, we described a multi-laboratory evaluation of the compounds in oxPAPC by LC-MS/MS, focusing on the identification and relative quantification of the lipid peroxidation products (LPPs) formed. PAPC was air-oxidized in four laboratories using the same protocol for 0, 48, and 72 h. It was possible to identify 55 different LPPs with unique elemental composition and characterize different structural isomeric species within these. The study showed good intra-sample reproducibility and similar qualitative patterns of oxidation, as the most abundant LPPs were essentially the same between the four laboratories. However, there were substantial differences in the extent of oxidation, i.e. the amount of LPPs relative to unmodified PAPC, at specific time points. This shows the importance of characterizing air-oxidized PAPC preparations before using them for testing biological effects of oxidized lipids, and may explain some variability of effects reported in the literature

”Långt borta men nära”- en studie om socialsekreterares förväntningar på chefer och syn på arbete

This masters degree was a study of some social workers in Gothenburg Community and their expectations of leaders in general, their opinions of work and the leaders influence. The city of Gothenburg will within a few years recruit about 500 leaders. Depending on large pensions among leaders. It is important to have knowledge of the social workers expectations of leaders, their opinions of work and the leaders influence. It is also interesting to see if different generations have similarities or if they have different opinions. The aim of our studie was to look in to and analyze the expectations of leaders in general, their opinions of work and the leaders influence, among twelve social workers in Gothenburg, who are working in the individ and family care. We also wanted to look in to what similarities and differences that accured between different generations, social workers born in the eighties centurie and social workers born in the fifthies century. We chosed these ages because of the time between them and because the fifthies have several years left before pension. The eighties have recently started to work and they will be a large group in the working life during many years. These generations have different background whish can influence their opinions. The results showed that social workers expectations of leaders are that the leaders must lead and organize the work. The leaders is expected to take responsibility for a nice climate at work The social workers wants leaders who are strong, kind, good-hearted and have humour. The social workers want a great deal of support from the leader. The leader should be close, still not too close. Feedback is very important for the social workers. They also want a leader to have competence and experiences in the specific work. The fifties want a leader who is personally mature. The eighties want a leader who are group-oriented, supporting and who takes care of the safety of work. The social workers want the work to be developing, challenging and self-developing. They want to have a part of a group and they want to have a work with a meaning. The work with the clients is a motivating factor. The fifties want to attribute to the society. The eighties want a work that gives them opportunities to development. The contact with working friends is also important. The leader has an influence of social workers opinions of work, by support, encouragement and engagement. The leader’s way of leading is also important. The most important way of influence is to give the young social workers possibilities to development. The wages is not a big factor. We used a qualitative method. We interviewed twelve social workers, six were born in the fifties and six were born in the eighties. The answers from the interviews were the ground for our studie. Our theoretical basics were Mintzbergs theory of leadership and Maslow’s theory of human needs. We used these therories, litteratur and previous reserche. We analyzed and diskussed our results while we showed our results

Biofilms in Nitrogen Removal - Bacterial Population Dynamics and Spatial Distribution

Efficient nitrogen removal at wastewater treatment plants (WWTPs) is necessary to avoid eutrophication of recipient waters. The most commonly used approach consists of aerobic nitrification and subsequent anaerobic denitrification resulting in the release of dinitrogen gas into the atmosphere. Nitrification is a two-step process performed by ammoniaoxidizing bacteria (AOB) and nitrite-oxidizing bacteria (NOB) often grown in biofilms at WWTPs. An alternative approach is anaerobic ammonium oxidation (anammox) where anammox bacteria convert ammonium and nitrite directly into dinitrogen gas. These groups of bacteria grow very slowly and are sensitive to perturbations, which may result in decreased efficiency or even breakdown of the process. Therefore, the ecology and activity of these bacteria and the structure of the biofilms in which they grow require detailed investigation to improve the understanding of nitrification and to facilitate the design of efficient nitrogen-removal strategies. To facilitate such studies of relevance for wastewater treatment, a nitrifying pilotplant was built where environmental conditions and especially ammonium concentrations could be controlled. In an experiment on model nitrifying trickling filters (NTFs), it was shown that biofilms subjected to intermittent feeding regimes of alternating high and low ammonium concentration in the water, could maintain a higher nitrification potential than biofilms constantly fed with low ammonium water. Such ammonium feed strategies can be used to optimize wastewater treatment performance. Different AOB populations within the N. oligotropha lineage were shown to respond differently to changes in environmental conditions, indicating microdiversity within this lineage which may be of importance for wastewater treatment. This diversity was further investigated through the development of new image analysis methods for analyzing bacterial spatial distribution in biofilms. The diversity within the N. oligotropha lineage was also reflected in the positioning of two such populations in the biofilm, where the vertical distribution patterns and relative positions compared to the NOB Nitrospira were different. In combination with a cryosectioning approach for retrieval of intact biofilm from small biofilm carrier compartments, the new image analysis methods showed a threedimensonal stratification of AOB-anammox biofilms. This may be of importance for mathematical modeling of such biofilms and the design of new biofilm carriers

Crisis Communication and Opinions Polarization : A study around SAS crisis communication

I februari 2020 utmanade SAS den nationalistiska uppfattningen om vad som verkligen var skandinaviskt genom en reklamfilm. Den här filmen möttes av kritik där flera av kritikerna kritiserade utifrån ett nationalistiskt perspektiv. Detta ledde till att SAS påbörjade en kriskommunikationsprocess där man från deras kommunikation kan utläsa främst tre strategier från Benoits Image repair theory. SAS nekade till anklagelserna, de försökte att sänka trovärdigheten hos kritikerna och de ändrade om sin kampanj. Likt tidigare forskning är slutsatsen i den här studien att SAS agerat otydligt i sin kommunikation vilket grundar sig i att de använt sig av för olika strategier som säger emot varandra. Denna situation kan liknas vid en dialog mellan SAS och respondenter. Vad den här dialogen slutar i är två sidor som vill förmedla en bild om vad som är skandinaviskt, en diskussion som delat många i Skandinavien.

Crisis Communication and Opinions Polarization : A study around SAS crisis communication

I februari 2020 utmanade SAS den nationalistiska uppfattningen om vad som verkligen var skandinaviskt genom en reklamfilm. Den här filmen möttes av kritik där flera av kritikerna kritiserade utifrån ett nationalistiskt perspektiv. Detta ledde till att SAS påbörjade en kriskommunikationsprocess där man från deras kommunikation kan utläsa främst tre strategier från Benoits Image repair theory. SAS nekade till anklagelserna, de försökte att sänka trovärdigheten hos kritikerna och de ändrade om sin kampanj. Likt tidigare forskning är slutsatsen i den här studien att SAS agerat otydligt i sin kommunikation vilket grundar sig i att de använt sig av för olika strategier som säger emot varandra. Denna situation kan liknas vid en dialog mellan SAS och respondenter. Vad den här dialogen slutar i är två sidor som vill förmedla en bild om vad som är skandinaviskt, en diskussion som delat många i Skandinavien.

Analysis of Endogenous Particles in Exhaled Air

Exhaled air contains non-volatile particulate material from the respiratory tract. The precise location in which exhaled particles are formed is unknown, and details on their chemical content are scarce. The aim of this work was to chemically characterize and to study the mechanisms of formation of endogenous particles in exhaled air. A new instrument for counting and sampling particles in exhaled air by impaction was developed, as a part of this thesis, at the Department of Public Health and Community Medicine, Occupational and Environmental Medicine in collaboration with the Department of Chemistry, Atmospheric Science at the University of Gothenburg. In the first instance, exhaled particles were analyzed using time-of-flight secondary ion mass spectrometry (TOF-SIMS), which is a very sensitive technique for surface analysis. This method was also used to compare the composition of particles in exhaled air from subjects with asthma to that in healthy controls. Second, a method for the quantitative determination of glutathione was developed and applied in the analysis of exhaled particles and exhaled breath condensate. In parallel to chemical analysis, the hypothesis that particles are formed during the reopening of closed airways was tested by measuring particle number concentrations in the air exhaled by healthy volunteers performing different breathing maneuvers. This is the first study involving chemical analysis of particles in exhaled air. TOF-SIMS analysis revealed that exhaled particles contain several phospholipids (phosphatidylcholine, phosphatidylglycerol and phosphatidylinositol). These lipids are characteristic of the pulmonary surfactant which is present in the respiratory tract lining fluid (RTLF) that covers the epithelium in the alveoli and the airways. Using this method, it was found that the TOF-SIMS spectra of the particles exhaled by healthy subjects differed from those of the particles exhaled by subjects with asthma. These differences were attributed to differences in the abundance of phosphatidylcholine and phosphatidylglycerol between the two groups. By using the newly-developed method for glutathione analysis, it was possible to demonstrate the presence of glutathione in exhaled particles for the first time. The method was used to compare glutathione levels in exhaled particles to those in exhaled breath condensate; it was found that analysis of particles was more revealing in terms of the levels of glutathione in exhaled air. Studies of particle formation showed that deep exhalations to residual volume (RV) caused significantly higher concentrations of particles in the subsequent exhalation than did exhalations to functional residual capacity (FRC).This supports the theory that film rupture during airway reopening after airway closure is an important mechanism of particle formation. The results of these studies show that particles in exhaled air can be sampled by impaction, that surfactant phospholipids and glutathione are part of their chemical composition, and that they are largely formed in the peripheral airways, where airway closure takes place