Probing the interaction between solid benzene and water using vacuum ultraviolet and infrared spectroscopy

We present results of a combined vacuum ultravioloet (VUV) and infrared (IR) photoabsorption study of amorphous benzene:water mixtures and layers to investigate the benzene-water interaction in the solid phase. UV spectra of 1:1, 1:10 and 1:100 benzene:water mixtures at 24 K reveal a concentration dependent shift in the energies of the 1B2u, 1B1u and 1E1u electronic states of benzene. All the electronic bands blueshift from pure amorphous benzene towards gas phase energies with increasing water concentration. IR results reveal a strong dOH-π benzene-water interaction via the dangling OH stretch of water with the delocalised π system of the benzene molecule. Although this interaction influences the electronic states of benzene with the benzenewater interaction causing a redshift in the electronic states from that of the free benzene molecule, the benzene-benzene interaction has a more significant effect on the electronic states of benzene. VUV spectra of benzene and water layers show evidence of non-wetting between benzene and water, characterised by Rayleigh scattering tails at wavelengths greater than 220 nm. Our results also show evidence of benzene-water interaction at the benzene-water interface affecting both the benzene and the water electronic states. Annealing the mixtures and layers of benzene and water show that benzene remains trapped within in/under water ice until water desorption near 160 K. These first systematic studies of binary amorphous mixtures in the VUV, supported with complementary IR studies, provide a deeper insight into the influence of intermolecular interactions on intramolecular electronic states with significant implications for our understanding of photochemical processes in more realistic astrochemical environments

Target Recognition by Natural Killer Cells : Identification and Characterization of Inhibiting and Activating Factors

Natural killer (NK) cells are able to attack and destroy tumorous or virally infected cells without prior sensitization. The processes that regulate their activation and function are still incompletely understood. NK cells do not exress a single clonal receptor like T-cells but many different activating and inhibitory receptors. Most of the inhibitory receptors bind to MHC I or related molecules. Some activating receptors recognize ligands induced upon cell stress or transformation. One group of inhibitory receptors on NK cells is constituted by the NKG2 family. Some of these receptors form antithetic pairs. That means, they recognize the same ligands but signal in a contrary fashion. One of the most important NKG2 receptors is NKG2D. For this receptor an antithetic counterpart has not been described yet. One part of this thesis included the identification of a possible inhibitory counterpart for NKG2D. Data base searches retrieved the cDNA for CLEC12B. Characterization of the receptor lead to the result that it did not bind the known NKG2D ligands and was not expressed on NK cells. Nevertheless, it is able to confer inhibitory signaling via the recruitment of the tyrosine-phosphatases SHP-1 and SHP-2. Expression of the inhibitory receptor CLEC12B was detected on monocyte-derived macrophages. Another important group of activating receptors is constituted by the natural cytotoxicity receptors (NCR). They have been implied in antiviral defense and in the recognition of malignant cells. Although the ligand remains unknown it is still possible to detect it by applying functional assays and staining methods using soluble fusion proteins. The role of the NCR ligands has up to now not been examined in human cytomegalovirus (HCMV) infection. Fusion protein staining and functional data presented in this thesis suggest that the NCR ligands are downregulated from the cell surface. This might constitute a new immune evasion mechanism of HCMV. It was discovered that this process is mediated by a viral gene product that is expressed de novo upon infection during the immediate early or early phase of infection. The creation of viral deletion mutants helped to exclude non-essential regions of the HCMV genome. Immunofluorescence staining with fusion proteins showed that the ligand is held back in intracellular compartments. For further research the elucidation of the NCR ligands is vitally important. Heparan sulfate structures have been postulated to function as ligands but these results are debated. In this thesis, it was established that heparan sulfate is not the functional ligand for NKp30. The putative ligand was found to involve a proteinacious component that is not GPI-anchored. It was tried to identify the NKp30 ligand with the help of a genomic siRNA library. Cells expressing the NKp30 ligand were transduced with the library and selected for cells with an NKp30 negative phenotype. The siRNAs were rescued from the cell population, amplified and analyzed via an affimetrix genechip. The results show the enrichment of some interesting transmembrane or secreted proteins as possible candidates that might function as ligand for NKp30

A New Molecular Detection System for Canine Distemper Virus Based on a Double-Check Strategy

Due to changing distemper issues worldwide and to inadequate results of an inter-laboratory study in Germany, it seems sensible to adapt and optimize the diagnostic methods for the detection of the canine distemper virus (CDV) to the new genetic diversity of virus strains. The goal of the project was the development, establishment and validation of two independent one-step reverse transcriptase quantitative polymerase chain reaction (RT-qPCR) methods for the safe detection of CDV in domestic and wild animals. For this purpose, an existing CDV-RT-qPCR was decisively adapted and, in addition, a completely new system was developed. Both CDV-RT-qPCR systems are characterized by a very high, comparable analytical and diagnostic sensitivity and specificity and can be mutually combined with inhibition or extraction controls. The reduction in the master mix used allows for the parallel implementation of both CDV-RT-qPCR systems without significant cost increases. For validation of the new CDV-RT-qPCR duplex assays, a panel comprising 378 samples derived from Germany, several European countries and one African country were tested. A sensitivity of 98.9% and a specificity of 100% were computed for the new assays, thus being a reliable molecular diagnostic tool for the detection of CDV in domestic and wild animals

Empathische Reaktionen gegenüber einem Roboter

Es ist bereits bekannt, dass Menschen soziale Reaktionen auf Computer und artifizielle Wesen wie virtuelle Agenten zeigen. Auch für die Mensch-Roboter-Interaktion konnten erste Studien zeigen, dass Menschen Verhalten zeigen, das man lediglich in der Mensch-Mensch-Kommunikation erwarten würde. Ob auch empathische Reaktionen gegenüber Robotern gezeigt werden, wurde bislang nicht untersucht. In einem 2x2 laborexperimentellen Design betrachteten die Probanden (N=40) zwei Filme, in denen ein Spielzeugroboter in Dinosaurierform entweder gequält oder gestreichelt wird (Treatmentfaktor 1, within subjects). Der einen Hälfte der Probanden wurde der Roboter vorab vorgestellt und 10 Minuten zum Kennenlernen überlassen, während der anderen Hälfte der Probanden der Roboter vollkommen fremd war (Treatment Faktor 2, between subjects). Nach jedem Video wurde das emotionale Befinden mit Hilfe der PANAS erhoben und die Probanden füllten am Ende einen Fragebogen zur Bewertung des Roboters aus. Nach der Rezeption des Videos, in dem der Roboter gequält wird, fühlten die Probanden sich signifikant schlechter (F(1/39)=26,946; p=.000). Die Bedingungsvariation der vorherigen Interaktion zeigte jedoch keinen Einfluss auf das emotionale Befinden nach der Rezeption des Videos oder die empfundene Empathie. Somit konnte gezeigt werden, dass eine negative Behandlung eines Roboters das eigene Empfinden beeinflusst, dass eine kurzzeitige Interaktion mit dem Roboter das Mitleiden aber nicht verstärkt

Methyl-CpG-binding (SmMBD2/3) and chromobox (SmCBX) proteins are required for neoblast proliferation and oviposition in the parasitic blood fluke Schistosoma mansoni

<div><p>While schistosomiasis remains a significant health problem in low to middle income countries, it also represents a recently recognised threat to more economically-developed regions. Until a vaccine is developed, this neglected infectious disease is primarily controlled by praziquantel, a drug with a currently unknown mechanism of action. By further elucidating how <i>Schistosoma</i> molecular components cooperate to regulate parasite developmental processes, next generation targets will be identified. Here, we continue our studies on schistosome epigenetic participants and characterise the function of a DNA methylation reader, the <i>Schistosoma mansoni</i> methyl-CpG-binding domain protein (SmMBD2/3). Firstly, we demonstrate that SmMBD2/3 contains amino acid features essential for 5-methyl cytosine (5mC) binding and illustrate that adult schistosome nuclear extracts (females > males) contain this activity. We subsequently show that SmMBD2/3 translocates into nuclear compartments of transfected murine NIH-3T3 fibroblasts and recombinant SmMBD2/3 exhibits 5mC binding activity. Secondly, using a yeast-two hybrid (Y2H) screen, we show that SmMBD2/3 interacts with the chromo shadow domain (CSD) of an epigenetic adaptor, <i>S</i>. <i>mansoni</i> chromobox protein (SmCBX). Moreover, fluorescent <i>in situ</i> hybridisation (FISH) mediated co-localisation of <i>Smmbd2/3</i> and <i>Smcbx</i> to mesenchymal cells as well as somatic- and reproductive- stem cells confirms the Y2H results and demonstrates that these interacting partners are ubiquitously expressed and found within both differentiated as well as proliferating cells. Finally, using RNA interference, we reveal that depletion of <i>Smmbd2/3</i> or <i>Smcbx</i> in adult females leads to significant reductions (46–58%) in the number of proliferating somatic stem cells (PSCs or neoblasts) as well as in the quantity of <i>in vitro</i> laid eggs. Collectively, these results further expand upon the schistosome components involved in epigenetic processes and suggest that pharmacological inhibition of SmMBD2/3 and/or SmCBX biology could prove useful in the development of future schistosomiasis control strategies.</p></div

Der Aufbau sozialer Beziehungen mit einem Roboter. Eine Beobachtungsstudie im Feld

Roboter nehmen in letzter Zeit vermehrt Einzug in verschiedene Lebensbereiche. Es werden nicht nur Haushaltsroboter, die staubsaugen, oder Roboter, die vorrangig Entertainment-Zwecken dienen, angeboten, sondern in einigen Altenheimen werden Roboter bereits eingesetzt, um Senioren Gesellschaft zu leisten. Vor diesem Hintergrund untersucht die Studie als Teil des EU Forschungsprojektes SERA (Social Engagement with Robots and Agents), ob und inwiefern soziale Beziehungen zu Robotern aufgebaut werden. In einer Beobachtungsstudie und einem anschließenden qualitativen Interview wurden drei weibliche Teilnehmer (zwischen 50 und 65 Jahren) über eine Woche in der Interaktion mit einem Nabaztag beobachtet. Dieser Roboter in Hasenform wurde für die Studie so programmiert, dass er mit den Untersuchungsteilnehmerinnen Dialoge rund um das Thema Gesundheit und Fitness führen konnte. Der Roboter nutzte Sprachoutput, der Input von Seiten der Teilnehmerinnen wurde über Ja/Nein Knöpfe vorgenommen. Mit einer Webcam wurden 66 Interaktionen aufgezeichnet. Die kategorienbasierte Auswertung der Transkripte zeigte z.B., dass der Nabaztag häufig natürlich-sprachlich adressiert wurde und ihm beispielsweise alltägliches Verhalten erklärt wurde, obwohl die Probandinnen wussten, dass der Roboter sie nicht verstehen kann, da eine Interaktion nur über die Knöpfe möglich war. Die Ergebnisse zeigen, dass durchaus Beziehungen aufgebaut werden und lassen Schlüsse über die soziale Natur des Menschen zu

Establishment of a Laboratory Scale Set-Up with Controlled Temperature and High Humidity to Investigate Dry Matter Losses of Wood Chips from Poplar during Storage

The aim of this work was to improve the understanding of dry matter losses (DML) that occur in wood chips during the initial phase of storage in outdoor piles. For this purpose, a laboratory scale storage chamber was developed and investigated regarding its ability to recreate the conditions that chips undergo during the initial phase of outdoor storage. Three trials with poplar Max-4 (Populus maximowiczii Henry  Populus nigra L.) chips were performed for 6–10 weeks in the storage chamber under controlled temperature and assisted humidity. Two different setups were investigated to maintain a high relative humidity (RH) inside the storage chamber; one using water containers, and one assisted with a humidifier. Moisture content (MC) and DML of the chips were measured at different storage times to evaluate their storage behaviour in the chamber. Additionally, microbiological analyses of the culturable fraction of saproxylic microbiota were performed, with a focus on mesophilic fungi, but discriminating also xerophilic fungi, and mesophilic bacteria, with focus on actinobacteria, in two trials, to gain a view on the poplar wood chip-inhabiting microorganisms as a function of storage conditions (moisture, temperature) and time. Results show that DML up to 8.8–13.7% occurred in the chips within 6–10 storage weeks. The maximum DML were reached in the trial using the humidifier, which seemed a suitable technique to keep a high RH in the testing chamber, and thus, to analyse the wood chips in conditions comparable to those in outdoor piles during the initial storage phase

Food groups and risk of coronary heart disease, stroke and heart failure : a systematic review and dose-response meta-analysis of prospective studies

Background: Despite growing evidence for food-based dietary patterns' potential to reduce cardiovascular disease risk, knowledge about the amounts of food associated with the greatest change in risk of specific cardiovascular outcomes and about the quality of meta-evidence is limited. Therefore, the aim of this meta-analysis was to synthesize the knowledge about the relation between intake of 12 major food groups (whole grains, refined grains, vegetables, fruits, nuts, legumes, eggs, dairy, fish, red meat, processed meat, and sugar-sweetened beverages [SSB]) and the risk of coronary heart disease (CHD), stroke and heart failure (HF). Methods: We conducted a systematic search in PubMed and Embase up to March 2017 for prospective studies. Summary risk ratios (RRs) and 95% confidence intervals (95% CI) were estimated using a random effects model for highest versus lowest intake categories, as well as for linear and non-linear relationships. Results: Overall, 123 reports were included in the meta-analyses. An inverse association was present for whole grains (RRCHD: 0.95 (95% CI: 0.92-0.98), RRHF: 0.96 (0.95-0.97)), vegetables and fruits (RRCHD: 0.97 (0.96-0.99), and 0.94 (0.90-0.97); RRstroke: 0.92 (0.86-0.98), and 0.90 (0.84-0.97)), nuts (RRCHD: 0.67 (0.43-1.05)), and fish consumption (RRCHD: 0.88 (0.79-0.99), RRstroke: 0.86 (0.75-0.99), and RRHF: 0.80 (0.67-0.95)), while a positive association was present for egg (RRHF: 1.16 (1.03-1.31)), red meat (RRCHD: 1.15 (1.08-1.23), RRstroke: 1.12 (1.06-1.17), RRHF: 1.08 (1.02-1.14)), processed meat (RRCHD: 1.27 (1.09-1.49), RRstroke: 1.17 (1.02-1.34), RRHF: 1.12 (1.05-1.19)), and SSB consumption (RRCHD: 1.17 (1.11-1.23), RRstroke: 1.07 (1.02-1.12), RRHF: 1.08 (1.05-1.12)) in the linear dose-response meta-analysis. There were clear indications for non-linear dose-response relationships between whole grains, fruits, nuts, dairy, and red meat and CHD. Conclusion: An optimal intake of whole grains, vegetables, fruits, nuts, legumes, dairy, fish, red and processed meat, eggs and SSB showed an important lower risk of CHD, stroke, and HF

Prevalence of chlamydial infections in fattening pigs and their influencing factors

Chlamydial infections in pigs are associated with respiratory disease, diarrhea, conjunctivitis and other pathologies. The aim of this study was to define the prevalence of Chlamydiaceae in Swiss fattening pigs by applying sensitive and specific detection methods and to correlate prior antibiotic treatment and farm related factors with differences in prevalence. Conjunctival and fecal swabs were collected from 636 pigs in 29 Swiss fattening pig farms with and without antibiotic treatment, at the beginning and the end of the fattening period. The swabs were screened by real-time PCR for Chlamydiaceae. For the chlamydial detection and species-identification, a DNA-microarray analysis was performed. All farms were positive for Chlamydiaceae with 94.3 and 92.0% prevalence in fecal swabs as well as 45.9 and 32.6% in conjunctival swabs at the first and second time points, respectively. Antibiotic treatment could not clear the infection on herd level. Potential contact with wild boars was a significant risk factor, while hygiene criteria did not influence chlamydial prevalence. A correlation of chlamydial positivity to diarrhea, but not to conjunctivitis was evident. Chlamydia suis was the predominant species. Mixed infections with C. suis and C. pecorum were common, with a substantial increase in C. pecorum positivity at the end of the fattening period, and this finding was associated with ruminant contact. C. abortus was detected in one conjunctival swab. In this study, C. suis inhabited the intestinal tract of nearly all examined pigs, implying a long-term infection. C. pecorum was also common and might be transmitted to pigs by ruminants