Motorisches Lernen in Drosophila melanogaster

In der vorliegenden Arbeit wurden die durch Training induzierten motorischen Gedächtnisleistungen der Taufliege Drosophila melanogaster beim Überklettern von acht symmetrisch verteilten Lücken auf einem rotierenden Ring untersucht. Durch den auf sie einwirkenden optischen Fluss der vorbeiziehenden äußeren Umgebung wurden die Fliegen angeregt, diesem optomotorischen Reiz entgegenzuwirken und die Lücken laufend zu überqueren. Durch Training verbessert und langfristig gelernt wird die kompensatorische Lückenüberquerung X+ gegen die Rotation. In der aus diesem Training erhaltenen Lernkurve war eine überdurchschnittlich hohe Leistungsverbesserung nach einem einzigen Trainingslauf mit einem zeitlichen Bestand von ca. 40 Minuten abzulesen, um danach vom motorischen Gedächtnisspeicher trainierter Fliegen nicht mehr abgerufen werden zu können. Nach einer Ruhephase von einem bis mehreren Tagen wurden die Fliegen auf mögliche Langzeitlernleistungen untersucht und diese für verschiedene Intervalle nachgewiesen. Sowohl die Leistungsverbesserung während des Trainings, als auch der Lerneffekt nach 24h bleiben in mutanten rutabaga2080 sowie rut1 Fliegen aus. Betroffen ist das Gen der Adenylylzyklase I, ein Schlüsselprotein der cAMP-Signalkaskade, die u.a. im olfaktorischen und visuellen Lernen gebraucht wird. Damit ergab sich die Möglichkeit die motorischen Gedächtnisformen durch partielle Rettung zu kartieren. Die motorische Gedächtniskonsolidierung ist schlafabhängig. Wie sich herausstellte, benötigen WTB Fliegen nur eine Dunkelphase von 10h zwischen einem ersten Trainingslauf und einem Testlauf um signifikante Leistungssteigerungen zu erzielen. In weiterführenden Versuchen wurden die Fliegen nachts sowie tagsüber mit einer LED-Lampe oder in einer Dunkelkammer, mit einem Kreisschüttler oder einer Laborwippe depriviert, mit dem Ergebnis, dass nur jene Fliegen ihre Leistung signifikant gegenüber einem ersten Trainingslauf verbessern konnten, welche entweder ausschließlich der Dunkelheit ausgesetzt waren oder welchen die Möglichkeit gegeben wurde, ein Gedächtnis zunächst in einer natürlichen Schlafphase zu konsolidieren (21Uhr bis 7Uhr MEZ). In weiteren Experimenten wurden die experimentellen Bedingungen entweder während des Trainings oder des Tests auf eine Fliege und damit verbunden auf eine erst durch das Training mögliche motorische Gedächtniskonsolidierung einwirken zu können, untersucht. Dazu wurden die Experimentparameter Lückenweite, Rotationsrichtung des Lückenringes, Geschwindigkeit des Lückenringes sowie die Verteilung der acht Lücken auf dem Ring (symmetrisch, asymmetrisch) im Training oder beim Gedächtnisabruf im Testlauf verändert. Aus den Ergebnissen kann geschlussfolgert werden, dass die Lückenweite langzeitkonsolidiert wird, die Rotationsrichtung kurzzeitig abgespeichert wird und die Drehgeschwindigkeit motivierend auf die Fliegen wirkt. Die symmetrische Verteilung der Lücken auf dem Ring dient der Langzeitkonsolidierung und ist als Trainingseingang von hoher Wichtigkeit. Mit Hilfe verschiedener Paradigmen konnten die Leistungsverbesserungen der Fliegen bei Abruf eines Kurz- bzw. Langzeitgedächtnisses hochauflösend betrachtet werden (Transfer). Die Konzentration, mit der eine WTB Fliege eine motorische Aufgabe - die Überquerung von Lücken entgegengesetzt der Rotationsrichtung - durchführt, konnte mit Hilfe von Distraktoreizen bestimmt werden. Wie sich herausstellte, haben Distraktoren einen Einfluss auf die Erfolgsquote einer Überquerung, d.h. mit zunehmender Distraktionsstärke nahm die Wahrscheinlichkeit einer Lückenüberquerung ab. Die Ablenkungsreize wirkten sich weiterhin auf die Vermessung einer Lücke aus, in dem entweder "peering"-artigen Bewegungen im Training durchgeführt wurden oder je nach Reizstärke ausschließlich nur jene Lücken vermessen wurden, welche auch überquert werden sollten.

Robust Nonlinear Output Regulation by Identification Tools

The present thesis focuses on the problem of robust output regulation for minimum phase nonlinear systems by means of identification techniques. Given a controlled plant and an exosystem (an autonomous system that generates eventual references or disturbances), the control goal is to design a proper regulator able to process the only measure available, i.e the error/output variable, in order to make it asymptotically vanishing. In this context, such a regulator can be designed following the well known “internal model principle” that states how it is possible to achieve the regulation objective by embedding a replica of the exosystem model in the controller structure. The main problem shows up when the exosystem model is affected by parametric or structural uncertainties, in this case, it is not possible to reproduce the exact behavior of the exogenous system in the regulator and then, it is not possible to achieve the control goal. In this work, the idea is to find a solution to the problem trying to develop a general framework in which coexist both a standard regulator and an estimator able to guarantee (when possible) the best estimate of all uncertainties present in the exosystem in order to give “robustness” to the overall control loop.

The Presence of Words in Visual Art from Surrealism to Conceptualism

Without a doubt, one of the biggest changes that affected XXth century art is the introduction of words into paintings and, in more recent years, in installations. For centuries, if words were part of a visual composition, they functioned as reference; strictly speaking, they were used as a guideline for a better perception of the subject represented. With the developments of the XXth century, words became a very important part of the visual composition, and sometimes embodied the composition itself. About this topic, American art critic and collector Russell Bowman wrote an interesting article called Words and images: A persistent paradox, in which he examines the American and the European art of the XXth century in almost its entirety, dividing it up in six “categories of intention”. The aforementioned categories are not based on the art history timeline, but on the role that language played for specific artists or movements. Taking inspiration from Bowman's article, this paper is structured in three chapters, respectively: words in juxtaposition and free association, words as means of exploration of language structures, and words as means for political and personal messages. The purpose of this paper is therefore to reflect on the role of language in contemporary art and on the way it has changed from artist to artist.

New and More Sustainable Processes for the Synthesis of Phenolics: 2-phenoxyethanol and hydroxytyrosol

The research work has dealt with the study of new catalytic processes for the synthesis of fine chemicals belonging to the class of phenolics, namely 2-phenoxyethanol and hydroxytyrosol. The two synthetic procedures investigated have the advantages of being much closer to the Green Chemistry principles than those currently used industrially. In both cases, the challenge was that of finding catalysts and methods which led to the production of less waste, and used less hazardous chemicals, safer solvents, and reusable heterogeneous catalysts. In the case of 2-phenoxyethanol, the process investigated involves the use of ethylene carbonate (EC) as the reactant for phenol O-hydroxyethylation, in place of ethylene oxide. Besides being a safer reactant, the major advantage of using EC in the new synthesis is the better selectivity to the desired product achieved. Moreover, the solid catalyst based on Na-mordenite was fully recyclable. The reaction mechanism and the effect of the Si/Al ratio in the mordenite were investigated. In the case of hydroxytyrosol, which is one of the most powerful natural antioxidants, a new synthetic procedure was investigated; in fact, the method currently employed, the hydrolysis of oleuropein, an ester extracted from the waste water processing of the olive, makes use of large amounts of organic solvents (hexane, ethyl acetate), and involves several expensive steps of purification. The synthesis procedure set up involves first the reaction between catechol and 2,2-dimethoxyacetaldehyde, followed by the one-pot reduction of the intermediate to give the desired product. Both steps were optimized, in terms of catalyst used, and of reaction conditions, that allowed to reach ca 70% yield in each step. The reaction mechanism was investigated and elucidated. During a 3-month period spent at the University of Valencia (with Prof. A. Corma’s group), a process for the production of diesel additives (2,5-bis(propoxymethyl)furan) from fructose has been investigated.

Quality control of virgin olive oils with regard to different storage and shipment conditions

Virgin olive oil(VOO) is a product characterized by high economic and nutritional values, because of its superior sensory characteristics and minor compounds (phenols and tocopherols) contents. Since the original quality of VOO may change during its storage, this study aimed to investigate the influence of different storage and shipment conditions on the quality of VOO, by studying different solutions such as filtration, dark storage and shipment inside insulated containers to protect it. Different analytical techniques were used to follow-up the quality changes during virgin olive oil storage and simulated shipments, in terms of basic quality parameters, sensory analysis and evaluation of minor components (phenolic compounds, diglycerides, volatile compounds). Four main research streams were presented in this PhD thesis: The results obtained from the first experimental section revealed that the application of filtration and/or clarification can decrease the unavoidable quality loss of the oil samples during storage, in comparison with unfiltered oil samples. The second section indicated that the virgin olive oil freshness, evaluated by diglycerides content, was mainly affected by the storage time and temperature. The third section revealed that fluctuation in temperature during storage may adversely affect the virgin olive oil quality, in terms of hydrolytic rancidity and oxidation quality. The fourth section showed that virgin olive oil shipped inside insulated containers showed lower hydrolytic and oxidation degradation than those without insulation cover. Overall, this PhD thesis highlighted that application of adequate treatment, such as filtration or clarification, in addition to a good protection against other external variables, such as temperature and light, will improve the stability of virgin olive oil during storage.

Ancient Greek harbours used as geo-archives for palaeotsunami research : case studies from Krane (Cefalonia), Lechaion (Gulf of Corinth) and Kyllini (Peloponnese)

Since historical times, coastal areas throughout the eastern Mediterranean are exposed to tsunami hazard. For many decades the knowledge about palaeotsunamis was solely based on historical accounts. However, results from timeline analyses reveal different characteristics affecting the quality of the dataset (i.e. distribution of data, temporal thinning backward of events, local periodization phenomena) that emphasize the fragmentary character of the historical data. As an increasing number of geo-scientific studies give convincing examples of well dated tsunami signatures not reported in catalogues, the non-existing record is a major problem to palaeotsunami research. While the compilation of historical data allows a first approach in the identification of areas vulnerable to tsunamis, it must not be regarded as reliable for hazard assessment. Considering the increasing economic significance of coastal regions (e.g. for mass tourism) and the constantly growing coastal population, our knowledge on the local, regional and supraregional tsunami hazard along Mediterranean coasts has to be improved. For setting up a reliable tsunami risk assessment and developing risk mitigation strategies, it is of major importance (i) to identify areas under risk and (ii) to estimate the intensity and frequency of potential events. This approach is most promising when based on the analysis of palaeotsunami research seeking to detect areas of high palaeotsunami hazard, to calculate recurrence intervals and to document palaeotsunami destructiveness in terms of wave run-up, inundation and long-term coastal change. Within the past few years, geo-scientific studies on palaeotsunami events provided convincing evidence that throughout the Mediterranean ancient harbours were subject to strong tsunami-related disturbance or destruction. Constructed to protect ships from storm and wave activity, harbours provide especially sheltered and quiescent environments and thus turned out to be valuable geo-archives for tsunamigenic high-energy impacts on coastal areas. Directly exposed to the Hellenic Trench and extensive local fault systems, coastal areas in the Ionian Sea and the Gulf of Corinth hold a considerably high risk for tsunami events, respectively.Geo-scientific and geoarcheaological studies carried out in the environs of the ancient harbours of Krane (Cefalonia Island), Lechaion (Corinth, Gulf of Corinth) and Kyllini (western Peloponnese) comprised on-shore and near-shore vibracoring and subsequent sedimentological, geochemical and microfossil analyses of the recovered sediments. Geophysical methods like electrical resistivity tomography and ground penetrating radar were applied in order to detect subsurface structures and to verify stratigraphical patterns derived from vibracores over long distances. The overall geochronological framework of each study area is based on radiocarbon dating of biogenic material and age determination of diagnostic ceramic fragments. Results presented within this study provide distinct evidence of multiple palaeotsunami landfalls for the investigated areas. Tsunami signatures encountered in the environs of Krane, Lechaion and Kyllini include (i) coarse-grained allochthonous marine sediments intersecting silt-dominated quiescent harbour deposits and/or shallow marine environments, (ii) disturbed microfaunal assemblages and/or (iii) distinct geochemical fingerprints as well as (iv) geo-archaeological destruction layers and (v) extensive units of beachrock-type calcarenitic tsunamites. For Krane, geochronological data yielded termini ad or post quem (maximum ages) for tsunami event generations dated to 4150 ± 60 cal BC, ~ 3200 ± 110 cal BC, ~ 650 ± 110 cal BC, and ~ 930 ± 40 cal AD, respectively. Results for Lechaion suggest that the harbour was hit by strong tsunami impacts in the 8th-6th century BC, the 1st-2nd century AD and in the 6th century AD. At Kyllini, the harbour site was affected by tsunami impact in between the late 7th and early 4th cent. BC and between the 4th and 6th cent. AD. In case of Lechaion and Kyllini, the final destruction of the harbour facilities also seems to be related to the tsunami impact. Comparing the tsunami signals obtained for each study areas with geo-scientific data from palaeotsunami events from other sites indicates that the investigated harbour sites represent excellent geo-archives for supra-regional mega-tsunamis.

Einsatz eines Aerosolmassenspektrometers während der CYPHEX-Kampagne und zur Methodenentwicklung einer Echtzeitquantifizierung gasförmiger Amine

Atmosphärische Aerosole haben einen starken Einfluss auf das Klima, der bisher nur grundlegend verstanden ist und weiterer Forschung bedarf. Das atmosphärische Verhalten der Aerosolpartikel hängt maßgeblich von ihrer Größe und chemischen Zusammensetzung ab. Durch Reflexion, Absorption und Streuung des Sonnenlichtes verändern sie den Strahlungshaushalt der Erde direkt und durch ihre Einflussnahme auf die Wolkenbildung indirekt. Besonders gealterte, stark oxidierte organische Aerosole mit großem Sauerstoff-zu-Kohlenstoff-Verhältnis wirken als effektive Wolkenkondensationskeime. Neben primären Aerosolpartikeln, die direkt partikelförmig in die Atmosphäre gelangen, spielen sekundäre Aerosolpartikel eine große Rolle, die aus Vorläufergasen in der Atmosphäre entstehen. Aktuelle Forschungsergebnisse legen nahe, dass kurzkettige aliphatische Amine bei Nukleationsprozessen beteiligt sind und somit die Partikelneubildung vielerorts mitsteuern. Um die Rolle von Aminen in der Atmosphäre besser erforschen und industrielle Emissionen kontrollieren zu können, bedarf es einer zuverlässigen Methode zur Echtzeitquantifizierung gasförmiger Amine mit hoher Zeitauflösung und niedriger Nachweisgrenze.rnDas hochauflösende Flugzeit-Aerosolmassenspektrometer (HR-ToF-AMS) bietet die Möglichkeit, atmosphärische Partikel in Echtzeit zu analysieren. Dabei werden Größe, Menge und grundlegende chemische Zusammensetzung erfasst. Anorganische Aerosolbestandteile können eindeutig zugeordnet werden. Es ist jedoch kaum möglich, einzelne organische Verbindungen in den komplizierten Massenspektren atmosphärischer Aerosole zu identifizieren und quantifizieren.rnIn dieser Arbeit wird atmosphärisches Aerosol untersucht, das im Westen Zyperns während der CYPHEX-Kampagne mit einem HR-ToF-AMS gemessen wurde. An diesem Standort ist vor allem stark gealtertes Aerosol vorzufinden, das aus Zentral- und Westeuropa stammt. Lokale Einflüsse spielen fast keine Rolle. Es wurde eine durchschnittliche Massenkonzentration von 10,98 μg/m3 gefunden, zusammengesetzt aus 57 % Sulfat, 30 % organischen Bestandteilen, 12 % Ammonium, < 1 % Nitrat und < 1 % Chlorid, bezogen auf das Gewicht. Der Median des vakuum-aerodynamischen Durchmessers betrug 446,25 nm. Es wurde sehr acides Aerosol gefunden, dessen anorganische Bestandteile weitgehend der Zusammensetzung von Ammoniumhydrogensulfat entsprachen. Tag-Nacht-Schwankungen in der Zusammensetzung wurden beobachtet. Die Sulfatkonzentration und die Acidität zeigten tagsüber Maxima und nachts Minima. Konzentrationsschwankungen an Nitrat und Chlorid zeigten einen weniger ausgeprägten Rhythmus, Maxima fallen aber immer mit Minima der Sulfatkonzentration, Aerosolacidität und Umgebungstemperatur zusammen. Organische Aerosolbestandteile entsprachen stark gealtertem, schwerflüchtigem oxidiertem organischem Aerosol. Es wurde eine interne Mischung der Partikel beobachtet, die ebenfalls meist bei alten Aerosolen auftritt.rnUm mit dem HR-ToF-AMS auch einzelne organische Verbindungen identifizieren und quantifizieren zu können, wurde eine Methode entwickelt, mit der man Amine der Gasphase selektiv in künstlich erzeugte Phosphorsäurepartikel aufnimmt und so für die HR-ToF-AMS-Messung zugänglich macht. Dadurch kombiniert man die Vorteile der Online-Messung des HR-ToF-AMS mit den Vorteilen klassischer Offline-Probenahmen. So können in Echtzeit sehr einfache Massenspektren gemessen werden, in denen störende Komponenten abgetrennt sind, während die Analyten eindeutig identifiziert werden können. Systeme dieser Art wurden GTRAP-AMS (Gaseous compound TRapping in Artificially-generated Particles – Aerosol Mass Spectrometry) genannt. Kalibrierungen für (Mono)Methylamin, Dimethylamin, Trimethylamin, Diethylamin und Triethylamin ergaben Nachweisgrenzen im ppt-Bereich bei einer Zeitauflösung von 3 min. Kammerexperimente zur Aminemission von Pflanzen zeigten eine gute Übereinstimmung des neu entwickelten Systems mit einer Gasdiffusionsabscheider-Offline-Probenahme und anschließender ionenchromatographischer Analyse. Beide Methoden zeigten Reaktionen der Pflanzen auf eine Veränderung der Lichtverhältnisse, während erhöhte Ozonkonzentrationen die Aminemission nicht veränderten. Die GTRAP-AMS-Methode eignet sich bereits für die Messung von Umgebungsluftkonzentrationen an einigen Orten, für die meisten Orte reicht die Nachweisgrenze allerdings noch nicht aus. Die Technik könnte bereits zur Echtzeitkontrolle industrieller Abgasemissionen eingesetzt werden.

Synthesis, properties and application of polyphenylene phosphonium salts

The central objective of this work was to generate weakly coordinating cations of unprecedented molecular size providing an inherently stable hydrophobic shell around a central charge. It was hypothesized that divergent dendritic growth by means of thermal [4+2] Diels-Alder cycloaddition might represent a feasible synthetic method to circumvent steric constraints and enable a drastic increase in cation size.rnThis initial proposition could be verified: applying the divergent dendrimer synthesis to an ethynyl-functionalized tetraphenylphosphonium derivative afforded monodisperse cations with precisely nanoscopic dimensions for the first time. Furthermore, the versatile nature of the applied cascade reactions enabled a throughout flexible design and structural tuning of the desired target cations. The specific surface functionalization as well as the implementation of triazolyl-moieties within the dendrimer scaffold could be addressed by sophisticated variation of the employed building block units (see chapter 3). rnDue to the steric screening provided by their large, hydrophobic and shape-persistent polyphenylene shells, rigidly dendronized cations proved more weakly coordinating compared to their non-dendronized analogues. This hypothesis has been experimentally confirmed by means of dielectric spectroscopy (see chapter 4). It was demonstrated for a series of dendronized borate salts that the degree of ion dissociation increased with the size of the cations. The utilization of the very large phosphonium cations developed within this work almost achieved to separate the charge carriers about the Bjerrum length in solvents of low polarity, which was reflected by approaching near quantitative ion dissociation even at room temperature. In addition to effect the electrolyte behavior in solution, the steric enlargement of ions could be visualized by means of several crystal structure analyses. Thus an insight into lattice packing under the effect of extraordinary large cations could be gathered. rnAn essential theme of this work focused on the application of benzylphosphonium salts in the classical Wittig reaction, where the concept of dendronization served as synthetic means to introduce an exceptionally large polyphenylene substituent at the -position. The straightforward influence of this unprecedented bulky group on the Wittig stereochemistry was investigated by NMR-analysis of the resulting alkenes. Based on the obtained data a valuable explanation for the origin of the observed selectivity was brought in line with the up-to-date operating [2+2] cycloaddition mechanism. Furthermore, a reliable synthesis protocol for unsymmetrically substituted polyphenylene alkenes and stilbenes was established by the design of custom-built polyphenylene precursors (see chapter 5).rnFinally, fundamental experiments to functionalize a polymer chain with sterically shielded ionic groups either in the pending or internal position were outlined within this work. Thus, inherently hydrophobic polysalts shall be formed so that future research can invesigate their physical properties with regard to counter ion condensation and charge carrier mobility.rnIn summary, this work demonstrates how the principles of dendrimer chemistry can be applied to modify and specifically tailor the properties of salts. The numerously synthesized dendrimer-ions shown herein represent a versatile interface between classic organic and inorganic electrolytes, and defined macromolecular structures in the nanometer-scale. Furthermore the particular value of polyphenylene dendrimers in terms of a broad applicability was illustrated. This work accomplished in an interdisciplinary manner to give answer to various questions such as structural modification of ions, the resulting influence on the electrolyte behavior, as well as the stereochemical control of organic syntheses via polyphenylene phosphonium salts. rn

Tradurre per le imprese. Analisi e traduzione in inglese della Nota integrativa al Bilancio consolidato 2013 di MNLG S.r.l.-Holding Sorma Group

The aim of this dissertation is to provide a translation in English of the Notes on the Consolidated Financial Statements of MNLG S.r.l., holding company of the Italian Sorma Group. This translation work is one example of the technical material produced in accordance with the project called Language Toolkit, set up by the Chamber of Commerce of Forlì-Cesena, to support the internationalization of the companies established in the territory. This initiative has represented a unique opportunity for me to put into practice the knowledge and abilities learnt in the translation field during these years at university. It also allowed me to give a concrete purpose to my dissertation, that is to provide a technical document translated into a foreign language. By making its Consolidated Financial Statement readily available in English, the company MNLG S.r.l. can in fact increase the number of possible investors and guarantee a more transparent financial informative to its shareholders. This translation work is divided into six chapters: the first one describes the project, its main objectives and the ways in which it was developed. The second chapter deals with the notions of Consolidated Financial Statements and presents the accounting documents of which the Financial Statements are made up as well as the norms according to which they are prepared. The third chapter, instead, focuses on the translation procedure applied and especially on the documentation process, analysing the differences between the International Accounting Standards and the accounting standards used in Italy. The fourth chapter provides a description of the translation resources built for the translation of this specific document. The fifth chapter includes the English version of the Notes on the Consolidated Financial Statements and, to conclude, the sixth chapter analyses the difficulties encountered in translating and the strategies adopted to overcome them.

An inter-comparison between a VIS/IR and a MW satellite-based methods for cloud detection and classification

This thesis is aimed to assess similarities and mismatches between the outputs from two independent methods for the cloud cover quantification and classification based on quite different physical basis. One of them is the SAFNWC software package designed to process radiance data acquired by the SEVIRI sensor in the VIS/IR. The other is the MWCC algorithm, which uses the brightness temperatures acquired by the AMSU-B and MHS sensors in their channels centered in the MW water vapour absorption band. At a first stage their cloud detection capability has been tested, by comparing the Cloud Masks they produced. These showed a good agreement between two methods, although some critical situations stand out. The MWCC, in effect, fails to reveal clouds which according to SAFNWC are fractional, cirrus, very low and high opaque clouds. In the second stage of the inter-comparison the pixels classified as cloudy according to both softwares have been. The overall observed tendency of the MWCC method, is an overestimation of the lower cloud classes. Viceversa, the more the cloud top height grows up, the more the MWCC not reveal a certain cloud portion, rather detected by means of the SAFNWC tool. This is what also emerges from a series of tests carried out by using the cloud top height information in order to evaluate the height ranges in which each MWCC category is defined. Therefore, although the involved methods intend to provide the same kind of information, in reality they return quite different details on the same atmospheric column. The SAFNWC retrieval being very sensitive to the top temperature of a cloud, brings the actual level reached by this. The MWCC, by exploiting the capability of the microwaves, is able to give an information about the levels that are located more deeply within the atmospheric column.

A probabilistic approach to classify the levee reliability

This work aims to evaluate the reliability of these levee systems, calculating the probability of “failure” of determined levee stretches under different loads, using probabilistic methods that take into account the fragility curves obtained through the Monte Carlo Method. For this study overtopping and piping are considered as failure mechanisms (since these are the most frequent) and the major levee system of the Po River with a primary focus on the section between Piacenza and Cremona, in the lower-middle area of the Padana Plain, is analysed. The novelty of this approach is to check the reliability of individual embankment stretches, not just a single section, while taking into account the variability of the levee system geometry from one stretch to another. This work takes also into consideration, for each levee stretch analysed, a probability distribution of the load variables involved in the definition of the fragility curves, where it is influenced by the differences in the topography and morphology of the riverbed along the sectional depth analysed as it pertains to the levee system in its entirety. A type of classification is proposed, for both failure mechanisms, to give an indication of the reliability of the levee system based of the information obtained by the fragility curve analysis. To accomplish this work, an hydraulic model has been developed where a 500-year flood is modelled to determinate the residual hazard value of failure for each stretch of levee near the corresponding water depth, then comparing the results with the obtained classifications. This work has the additional the aim of acting as an interface between the world of Applied Geology and Environmental Hydraulic Engineering where a strong collaboration is needed between the two professions to resolve and improve the estimation of hydraulic risk.

Response of gram-positive bacteria to copper stress

The Gram-positive bacteria Enterococcus hirae, Lactococcus lactis, and Bacillus subtilis have received wide attention in the study of copper homeostasis. Consequently, copper extrusion by ATPases, gene regulation by copper, and intracellular copper chaperoning are understood in some detail. This has provided profound insight into basic principles of how organisms handle copper. It also emerged that many bacterial species may not require copper for life, making copper homeostatic systems pure defense mechanisms. Structural work on copper homeostatic proteins has given insight into copper coordination and bonding and has started to give molecular insight into copper handling in biological systems. Finally, recent biochemical work has shed new light on the mechanism of copper toxicity, which may not primarily be mediated by reactive oxygen radicals.

Can health beliefs help in explaining attendance to follow-up care? The Swiss Childhood Cancer Survivor Study

Objective: Improved treatment has increased the survival of childhood cancer patients in recent decades, but follow-up care is recommended to detect and treat late effects. We investigated relationships between health beliefs and follow-up attendance in adult childhood cancer survivors. Methods: Childhood cancer survivors aged younger than 16 years when diagnosed between 1976 and 2003, who had survived for more than 5 years and were currently aged 201 years, received a postal questionnaire. We asked survivors whether they attended follow-up in the past year. Concepts from the Health Belief Model (perceived susceptibility and severity of future late effects, potential benefits and barriers to follow-up, general health value and cues to action) were assessed. Medical information was extracted from the Swiss Childhood Cancer Registry. Results: Of 1075 survivors (response rate 72.3%), 250 (23.3%) still attended regular followup care. In unadjusted analyses, all health belief concepts were significantly associated with follow-up (po0.05). Adjusting for other health beliefs, demographic, and medical variables, only barriers (OR50.59; 95%CI: 0.43–0.82) remained significant. Younger survivors, those with lower educational background, diagnosed at an older age, treated with chemotherapy, radiotherapy, or bone marrow transplantation and with a relapse were more likely to attend follow-up care. Conclusions: Our study showed that more survivors at high risk of cancer- and treatmentrelated late effects attend follow-up care in Switzerland. Patient-perceived barriers hinder attendance even after accounting for medical variables. Information about the potential effectiveness and value of follow-up needs to be available to increase the attendance among childhood cancer survivors.

A sequential Cox approach for estimating the causal effect of treatment in the presence of time-dependent confounding applied to data from the Swiss HIV Cohort Study

When estimating the effect of treatment on HIV using data from observational studies, standard methods may produce biased estimates due to the presence of time-dependent confounders. Such confounding can be present when a covariate, affected by past exposure, is both a predictor of the future exposure and the outcome. One example is the CD4 cell count, being a marker for disease progression for HIV patients, but also a marker for treatment initiation and influenced by treatment. Fitting a marginal structural model (MSM) using inverse probability weights is one way to give appropriate adjustment for this type of confounding. In this paper we study a simple and intuitive approach to estimate similar treatment effects, using observational data to mimic several randomized controlled trials. Each 'trial' is constructed based on individuals starting treatment in a certain time interval. An overall effect estimate for all such trials is found using composite likelihood inference. The method offers an alternative to the use of inverse probability of treatment weights, which is unstable in certain situations. The estimated parameter is not identical to the one of an MSM, it is conditioned on covariate values at the start of each mimicked trial. This allows the study of questions that are not that easily addressed fitting an MSM. The analysis can be performed as a stratified weighted Cox analysis on the joint data set of all the constructed trials, where each trial is one stratum. The model is applied to data from the Swiss HIV cohort study.

Gender Differences in Emotional Responses to Hooking Up

The present research looked to explore the relationship between the emotional responses of college students to different hooking up behaviors. Seven hundred and nine undergraduates participated in a web-based survey that included a demographic questionnaire, SDS, PANAS, AUDIT, and a measure of hooking up. This measure examined the frequency with which they participated in eight different types of hooking up varying by degree of familiarity to their hook partner and whether or not the hook up was coital or non-coital, as well as their emotional responses to the behavior and their perception of the emotional responses of their partner. Results showed that both menand women experienced more positive emotional responses to hooking up behaviors than negative emotional responses. Men experienced significantly more positive emotional responses to hook up behaviors than did women. Women experienced significantly more negative emotional responses for hook ups that were coital with strangers than did men, while men experienced more positive emotional responses for hook ups that were coital with strangers, coital with acquaintances, and coital with partners that were previous romantic partners than did women. Men also experienced more positive emotional responses for hook ups that were non-coital with strangers and non-coital withacquaintances. Men tended to rate their partner’s positive emotional responses higher than what women reported experiencing, particularly for hook ups with less familiar partners. Women’s ratings of their partner’s negative emotional responses were lower than what men actually reported experiencing. The data collected provide several opportunities for future analyses to be conducted and this research will add to the relatively small body of literature on hooking up.