Velocity structure and seismic anisotropy in the crust and upper mantle from Receiver Function analysis: three case studies in Italy

The research for this PhD project consisted in the application of the RFs analysis technique to different data-sets of teleseismic events recorded at temporary and permanent stations located in three distinct study regions: Colli Albani area, Northern Apennines and Southern Apennines. We found some velocity models to interpret the structures in these regions, which possess very different geologic and tectonics characteristics and therefore offer interesting case study to face. In the Colli Albani some of the features evidenced in the RFs are shared by all the analyzed stations: the Moho is almost flat and is located at about 23 km depth, and the presence of a relatively shallow limestone layer is a stable feature; contrariwise there are features which vary from station to station, indicating local complexities. Three seismic stations, close to the central part of the former volcanic edifice, display relevant anisotropic signatures­­­ with symmetry axes consistent with the emplacement of the magmatic chamber. Two further anisotropic layers are present at greater depth, in the lower crust and the upper mantle, respectively, with symmetry axes directions related to the evolution of the volcano complex. In Northern Apennines we defined the isotropic structure of the area, finding the depth of the Tyrrhenian (almost 25 km and flat) and Adriatic (40 km and dipping underneath the Apennines crests) Mohos. We determined a zone in which the two Mohos overlap, and identified an anisotropic body in between, involved in the subduction and going down with the Adiratic Moho. We interpreted the downgoing anisotropic layer as generated by post-subduction delamination of the top-slab layer, probably made of metamorphosed crustal rocks caught in the subduction channel and buoyantly rising toward the surface. In the Southern Apennines, we found the Moho depth for 16 seismic stations, and highlighted the presence of an anisotropic layer underneath each station, at about 15-20 km below the whole study area. The moho displays a dome-like geometry, as it is shallow (29 km) in the central part of the study area, whereas it deepens peripherally (down to 45 km); the symmetry axes of anisotropic layer, interpreted as a layer separating the upper and the lower crust, show a moho-related pattern, indicated by the foliation of the layer which is parallel to the Moho trend. Moreover, due to the exceptional seismic event occurred on April 6th next to L’Aquila town, we determined the Vs model for two station located next to the epicenter. An extremely high velocity body is found underneath AQU station at 4-10 km depth, reaching Vs of about 4 km/s, while this body is lacking underneath FAGN station. We compared the presence of this body with other recent works and found an anti-correlation between the high Vs body, the max slip patches and earthquakes distribution. The nature of this body is speculative since such high velocities are consistent with deep crust or upper mantle, but can be interpreted as a as high strength barrier of which the high Vs is a typical connotation.

Inferences on earthquake kinematic properties from data inversion: two different approaches

During my PhD, starting from the original formulations proposed by Bertrand et al., 2000 and Emolo & Zollo 2005, I developed inversion methods and applied then at different earthquakes. In particular large efforts have been devoted to the study of the model resolution and to the estimation of the model parameter errors. To study the source kinematic characteristics of the Christchurch earthquake we performed a joint inversion of strong-motion, GPS and InSAR data using a non-linear inversion method. Considering the complexity highlighted by superficial deformation data, we adopted a fault model consisting of two partially overlapping segments, with dimensions 15x11 and 7x7 km2, having different faulting styles. This two-fault model allows to better reconstruct the complex shape of the superficial deformation data. The total seismic moment resulting from the joint inversion is 3.0x1025 dyne.cm (Mw = 6.2) with an average rupture velocity of 2.0 km/s. Errors associated with the kinematic model have been estimated of around 20-30 %. The 2009 Aquila sequence was characterized by an intense aftershocks sequence that lasted several months. In this study we applied an inversion method that assumes as data the apparent Source Time Functions (aSTFs), to a Mw 4.0 aftershock of the Aquila sequence. The estimation of aSTFs was obtained using the deconvolution method proposed by Vallée et al., 2004. The inversion results show a heterogeneous slip distribution, characterized by two main slip patches located NW of the hypocenter, and a variable rupture velocity distribution (mean value of 2.5 km/s), showing a rupture front acceleration in between the two high slip zones. Errors of about 20% characterize the final estimated parameters.

Soil biogenic emissions of nitric oxide from arid and semi-arid ecosystems

The biogenic production of NO in the soil accounts for between 10% and 40% of the global total. A large degree of the uncertainty in the estimation of the biogenic emissions stems from a shortage of measurements in arid regions, which comprise 40% of the earth’s land surface area. This study examined the emission of NO from three ecosystems in southern Africa which cover an aridity gradient from semi-arid savannas in South Africa to the hyper-arid Namib Desert in Namibia. A laboratory method was used to determine the release of NO as a function of the soil moisture and the soil temperature. Various methods were used to up-scale the net potential NO emissions determined in the laboratory to the vegetation patch, landscape or regional level. The importance of landscape, vegetation and climatic characteristics is emphasized. The first study occurred in a semi-arid savanna region in South Africa, where soils were sampled from 4 landscape positions in the Kruger National Park. The maximum NO emission occurred at soil moisture contents of 10%-20% water filled pore space (WFPS). The highest net potential NO emissions came from the low lying landscape positions, which have the largest nitrogen (N) stocks and the largest input of N. Net potential NO fluxes obtained in the laboratory were converted in field fluxes for the period 2003-2005, for the four landscape positions, using soil moisture and temperature data obtained in situ at the Kruger National Park Flux Tower Site. The NO emissions ranged from 1.5-8.5 kg ha-1 a-1. The field fluxes were up-scaled to a regional basis using geographic information system (GIS) based techniques, this indicated that the highest NO emissions occurred from the Midslope positions due to their large geographical extent in the research area. Total emissions ranged from 20x103 kg in 2004 to 34x103 kg in 2003 for the 56000 ha Skukuza land type. The second study occurred in an arid savanna ecosystem in the Kalahari, Botswana. In this study I collected soils from four differing vegetation patch types including: Pan, Annual Grassland, Perennial Grassland and Bush Encroached patches. The maximum net potential NO fluxes ranged from 0.27 ng m-2 s-1 in the Pan patches to 2.95 ng m-2 s-1 in the Perennial Grassland patches. The net potential NO emissions were up-scaled for the year December 2005-November 2006. This was done using 1) the net potential NO emissions determined in the laboratory, 2) the vegetation patch distribution obtained from LANDSAT NDVI measurements 3) estimated soil moisture contents obtained from ENVISAT ASAR measurements and 4) soil surface temperature measurements using MODIS 8 day land surface temperature measurements. This up-scaling procedure gave NO fluxes which ranged from 1.8 g ha-1 month-1 in the winter months (June and July) to 323 g ha-1 month-1 in the summer months (January-March). Differences occurred between the vegetation patches where the highest NO fluxes occurred in the Perennial Grassland patches and the lowest in the Pan patches. Over the course of the year the mean up-scaled NO emission for the studied region was 0.54 kg ha-1 a-1 and accounts for a loss of approximately 7.4% of the estimated N input to the region. The third study occurred in the hyper-arid Namib Desert in Namibia. Soils were sampled from three ecosystems; Dunes, Gravel Plains and the Riparian zone of the Kuiseb River. The net potential NO flux measured in the laboratory was used to estimate the NO flux for the Namib Desert for 2006 using modelled soil moisture and temperature data from the European Centre for Medium Range Weather Forecasts (ECMWF) operational model on a 36km x 35km spatial resolution. The maximum net potential NO production occurred at low soil moisture contents (<10%WFPS) and the optimal temperature was 25°C in the Dune and Riparian ecosystems and 35°C in the Gravel Plain Ecosystems. The maximum net potential NO fluxes ranged from 3.0 ng m-2 s-1 in the Riparian ecosystem to 6.2 ng m-2 s-1 in the Gravel Plains ecosystem. Up-scaling the net potential NO flux gave NO fluxes of up to 0.062 kg ha-1 a-1 in the Dune ecosystem and 0.544 kg h-1 a-1 in the Gravel Plain ecosystem. From these studies it is shown that NO is emitted ubiquitously from terrestrial ecosystems, as such the NO emission potential from deserts and scrublands should be taken into account in the global NO models. The emission of NO is influenced by various factors such as landscape, vegetation and climate. This study looks at the potential emissions from certain arid and semi-arid environments in southern Africa and other parts of the world and discusses some of the important factors controlling the emission of NO from the soil.

Multilevel Domain Decomposition Algorithms for Monolithic Fluid-Structure Interaction Problems with Application to Haemodynamics

Finite element techniques for solving the problem of fluid-structure interaction of an elastic solid material in a laminar incompressible viscous flow are described. The mathematical problem consists of the Navier-Stokes equations in the Arbitrary Lagrangian-Eulerian formulation coupled with a non-linear structure model, considering the problem as one continuum. The coupling between the structure and the fluid is enforced inside a monolithic framework which computes simultaneously for the fluid and the structure unknowns within a unique solver. We used the well-known Crouzeix-Raviart finite element pair for discretization in space and the method of lines for discretization in time. A stability result using the Backward-Euler time-stepping scheme for both fluid and solid part and the finite element method for the space discretization has been proved. The resulting linear system has been solved by multilevel domain decomposition techniques. Our strategy is to solve several local subproblems over subdomain patches using the Schur-complement or GMRES smoother within a multigrid iterative solver. For validation and evaluation of the accuracy of the proposed methodology, we present corresponding results for a set of two FSI benchmark configurations which describe the self-induced elastic deformation of a beam attached to a cylinder in a laminar channel flow, allowing stationary as well as periodically oscillating deformations, and for a benchmark proposed by COMSOL multiphysics where a narrow vertical structure attached to the bottom wall of a channel bends under the force due to both viscous drag and pressure. Then, as an example of fluid-structure interaction in biomedical problems, we considered the academic numerical test which consists in simulating the pressure wave propagation through a straight compliant vessel. All the tests show the applicability and the numerical efficiency of our approach to both two-dimensional and three-dimensional problems.

Development of a field method to assess root parasites of woody plants - ecological analyses of the grapevine-phylloxera interaction

The development and the growth of plants is strongly affected by the interactions between roots, rootrnassociated organisms and rhizosphere communities. Methods to assess such interactions are hardly torndevelop particularly in perennial and woody plants, due to their complex root system structure and theirrntemporal change in physiology patterns. In this respect, grape root systems are not investigated veryrnwell. The aim of the present work was the development of a method to assess and predict interactionsrnat the root system of rootstocks (Vitis berlandieri x Vitis riparia) in field. To achieve this aim, grapernphylloxera (Daktulosphaira vitifoliae Fitch, Hemiptera, Aphidoidea) was used as a graperoot parasitizingrnmodel.rnTo develop the methodical approach, a longt-term trial (2006-2009) was arranged on a commercial usedrnvineyard in Geisenheim/Rheingau. All 2 to 8 weeks the top most 20 cm of soil under the foliage wallrnwere investigated and root material was extracted (n=8-10). To include temporal, spatial and cultivarrnspecific root system dynamics, the extracted root material was analyzed digitally on the morphologicalrnproperties. The grape phylloxera population was quantified and characterized visually on base of theirrnlarvalstages (oviparous, non oviparous and winged preliminary stages). Infection patches (nodosities)rnwere characterized visually as well, partly supported by digital root color analyses. Due to the knownrneffects of fungal endophytes on the vitality of grape phylloxera infested grapevines, fungal endophytesrnwere isolated from nodosity and root tissue and characterized (morphotypes) afterwards. Further abioticrnand biotic soil conditions of the vineyards were assessed. The temporal, spatial and cultivar specificrnsensitivity of single parameters were analyzed by omnibus tests (ANOVAs) and adjacent post-hoc tests.rnThe relations between different parameters were analyzed by multiple regression models.rnQuantitative parameters to assess the degeneration of nodosity, the development nodosity attachedrnroots and to differentiate between nodosities and other root swellings in field were developed. Significantrndifferences were shown between root dynamic including parameters and root dynamic ignoringrnparameters. Regarding the description of grape phylloxera population and root system dynamic, thernmethod showed a high temporal, spatial and cultivar specific sensitivity. Further, specific differencesrncould be shown in the frequency of endophyte morphotypes between root and nodosity tissue as wellrnas between cultivars. Degeneration of nodosities as well as nodosity occupation rates could be relatedrnto the calculated abundances of grape phylloxera population. Further ecological questions consideringrngrape root development (e.g. relation between moisture and root development) and grape phylloxerarnpopulation development (e.g. relation between temperature and population structure) could be answeredrnfor field conditions.rnGenerally, the presented work provides an approach to evaluate vitality of grape root systems. Thisrnapproach can be useful, considering the development of control strategies against soilborne pests inrnviticulture (e.g. grape phylloxera, Sorospheara viticola, Roesleria subterranea (Weinm.) Redhaed) as well as considering the evaluation of integrated management systems in viticulture.

Numerical modeling of the Alto Tiberina low angle normal fault

The aim of this Thesis is to obtain a better understanding of the mechanical behavior of the active Alto Tiberina normal fault (ATF). Integrating geological, geodetic and seismological data, we perform 2D and 3D quasi-static and dynamic mechanical models to simulate the interseismic phase and rupture dynamic of the ATF. Effects of ATF locking depth, synthetic and antithetic fault activity, lithology and realistic fault geometries are taken in account. The 2D and 3D quasi-static model results suggest that the deformation pattern inferred by GPS data is consistent with a very compliant ATF zone (from 5 to 15 km) and Gubbio fault activity. The presence of the ATF compliant zone is a first order condition to redistribute the stress in the Umbria-Marche region; the stress bipartition between hanging wall (high values) and footwall (low values) inferred by the ATF zone activity could explain the microseismicity rates that are higher in the hanging wall respect to the footwall. The interseismic stress build-up is mainly located along the Gubbio fault zone and near ATF patches with higher dip (30°

Intra- and interspecific competition in western barbastelle bats (Barbastella barbastellus, SCHREBER 1774)

In the present thesis I examined individual and sex-specific habitat use and site fidelity in the western barbastelle bat, Barbastella barbastellus, using data from a four-year monitoring in a Special Area of Conservation in Rhineland-Palatinate, Germany. The western barbastelle occurs in central and southern Europe from Portugal to the Caucasus, but is considered to be rare in large parts of its range. Up to now, long-term field studies to assess interannual site fidelity and the possible effects of intra- and interspecific competition have not been studied in this species. Nevertheless, such data provide important details to estimate the specific spatial requirements of its populations, which in turn can be incorporated in extended conservation actions. I used radio-telemetry, home range analyses und automated ultrasound detection to assess the relation between landscape elements and western barbastelle bats and their roosts. In addition, I estimated the degree of interspecific niche overlap with two selected forest-dwelling bat species, Bechstein's bat (Myotis bechsteinii) and the brown long-eared bat (Plecotus auritus). Intra- and interannual home range overlap analyses of female B. barbastellus revealed that fidelity to individual foraging grounds, i.e. a traditional use of particular sites, seems to effect the spatial distribution of home ranges more than intraspecific competition among communally roosting females. The results of a joint analysis of annual maternity roost selection and flight activities along commuting corridors highlight the necessity to protect roost complexes in conjunction with commuting corridors. Using radio-tracking data and an Euclidean distance approach I quantified the sex-specific and individual habitat use by female and male western barbastelle bats within their home ranges. My data indicated a partial sexual segregation in summer habitats. Females were found in deciduous forest patches and preferably foraged along linear elements within the forest. Males foraged closer to forest edges and in open habitats. Finally, I examined the resource partitioning between the western barbastelle bat and two syntopic bat species with a potential for interspecific competition due to similarities in foraging strategies, prey selection and roost preferences. Simultaneous radio-tracking of mixed-species pairs revealed a partial spatial separation of the three syntopic bat species along a gradient from the forest to edge habitats and open landscape. Long-eared bats were found close to open habitats which were avoided by the other two species. B. barbastellus preferred linear landscape elements (edge habitats) and forests, M. bechsteinii also preferred forest habitats. Only little overlap in terms of roost structure and tree species selection was found.

Complex colloids by the emulsion solvent evaporation process

In this thesis, different complex colloids were prepared by the process of solvent evaporation from emulsion droplets (SEED). The term “complex” is used to include both an addressable functionality as well as the heterogeneous nature of the colloids.Firstly, as the SEED process was used throughout the thesis, its mechanism especially in regard to coalescence was investigated,. A wide variety of different techniques was employed to study the coalescence of nanodroplets during the evaporation of the solvent. Techniques such as DLS or FCS turned out not to be suitable methods to determine droplet coalescence because of their dependence on dilution. Thus, other methods were developed. TEM measurements were conducted on mixed polymeric emulsions with the results pointing to an absence of coalescence. However, these results were not quantifiable. FRET measurements on mixed polymeric emulsions also indicated an absence of coalescence. Again the results were not quantifiable. The amount of coalescence taking place was then quantified by the application of DC-FCCS. This method also allowed for measuring coalescence in other processes such as the miniemulsion polymerization or the polycondensation reaction on the interface of the droplets. By simulations it was shown that coalescence is not responsible for the usually observed broad size distribution of the produced particles. Therefore, the process itself, especially the emulsification step, needs to be improved to generate monodisperse colloids.rnThe Janus morphology is probably the best known among the different complex morphologies of nanoparticles. With the help of functional polymers, it was possible to marry click-chemistry to Janus particles. A large library of functional polymers was prepared by copolymerization and subsequent post-functionalization or by ATRP. The polymers were then used to generate Janus particles by the SEED process. Both dually functionalized Janus particles and particles with one functionalized face could be obtained. The latter were used for the quantification of functional groups on the surface of the Janus particles. For this, clickable fluorescent dyes were synthesized. The degree of functionality of the polymers was found to be closely mirrored in the degree of functionality of the surface. Thus, the marriage of click-chemistry to Janus particles was successful.Another complex morphology besides Janus particles are nanocapsules. Stimulus-responsive nanocapsules that show triggered release are a highly demanding and interesting system, as nanocapsules have promising applications in drug delivery and in self-healing materials. To achieve heterogeneity in the polymer shell, the stimulus-responsive block copolymer PVFc-b-PMMA was employed for the preparation of the capsules. The phase separation of the two blocks in the shell of the capsules led to a patchy morphology. These patches could then be oxidized resulting in morphology changes. In addition, swelling occurred because of the hydrophobic to hydrophilic transition of the patches induced by the oxidation. Due to the swelling, an encapsulated payload could diffuse out of the capsules, hence release was achieved.The concept of using block copolymers responsive to one stimulus for the preparation of stimulus-responsive capsules was extended to block copolymers responsive to more than one stimulus. Here, a block copolymer responsive to oxidation and a pH change as well as a block copolymer responsive to a pH change and temperature were studied in detail. The release from the nanocapsules could be regulated by tuning the different stimuli. In addition, by encapsulating stimuli-responsive payloads it was possible to selectively release a payload upon one stimulus but not upon the other one.In conclusion, the approaches taken in the course of this thesis demonstrate the broad applicability and usefulness of the SEED process to generate complex colloids. In addition, the experimental techniques established such as DC-FCCS will provide further insight into other research areas as well.

Zur Karbonatsedimentologie, Biofazies und sequenzstratigraphischen Architektur eines fossilen Hochenergie-Schelfs aus dem Neogen der Algarve (Miozän, Südportugal)

Die neogene Lagos-Portimão Formation (Unter- bis Mittelmiozän) bildet einen Teil der Steilküste der Algarve (S-Portugal) und besteht aus einer zyklischen Wechsellagerung von Karbonaten und Sand-steinen. Die vorliegende Arbeit bietet ein Modell zur sedimentologischen, faziellen und stratigraphischen Entwicklung dieser Einheit an. Basierend auf Profilen entlang der gesamten lateralen Erstreckung der Einheit wurden verschiedene Gelände- und Labormethoden angewandt, um ein Modell entwickeln zu können. Messungen des Sr87/86-Isotopenverhältnisses sollten Klarheit bezüglich der stratigraphischen Position bringen. Die laterale Korrelation der Profile erfolgte über lithologische und fazielle Ansprachen. Unterstützend wurden einzelne Profile mit einem tragbaren Gammaray-Spektrometer gemessen. Es wurden vier Leithorizonte etabliert, die sich durch fazielle Merkmale und spezielle Fossilführung defi-nieren lassen. Die Mikrofazies wurde qualitativ und quantitativ analysiert. Als statistisches Verfahren wurde unter anderem eine hierarchische Clusteranalyse durchgeführt, über welche fünf Biofaziestypen des warm-temperierten Klimabereichs unterschieden werden. Die Fossilführung wird von Mollusken, Bryozoen und Rotalgen dominiert. Ausnahmen bilden stratigraphisch isolierte Vorkommen von kolo-nialen Korallen, die jedoch keine Riffkörper aufbauen. Die Ergebnisse aller zuvor erwähnten Untersuchungen deuten auf Ablagerungen eines nicht-tropischen Hochenergie-Schelfs hin. Sedimentäre Zyklen sind oftmals unvollständig, es treten Hartgründe und Auf-arbeitungs- bzw- Kondesationshorizonte auf. Die geochemische Altersdatierung weist Alterssprünge und -inversionen auf. Ein Vergleich mit dem SW-australischen Schelf und dem von James et al. (1994) eingeführten Modell des shaved shelf bietet sich aufgrund der Ähnlichkeit der Sedimentgesteine und des ozeanographischen Settings an. Weiterhin werden zeitgleiche bzw. faziell ähnliche Becken vergleichend diskutiert. Das Sedimentationsgeschehen der Lagos-Portimão Formation wird maßgeblich durch eine halokinetisch bedingte unregelmäßige Subsidenz und Hebung beeinflußt. Der Salzdom von Albufeira war während der Sedimentation der Einheit mehrfach in Bewegung. Rutschungspakete, Entlastungsspalten und Sanddikes zeugen davon. Die sequenzstratigraphische Interpretation bietet einen neuen Ansatz, in dem sie von Hochstand-Sandsteinen und Tiefstand-Karbonaten ausgeht.

Determination of Pelvic Orientation from Ultrasound Images Using Patch-SSMs and a Hierarchical Speed of Sound Compensation Strategy

In the field of computer assisted orthopedic surgery (CAOS) the anterior pelvic plane (APP) is a common concept to determine the pelvic orientation by digitizing distinct pelvic landmarks. As percutaneous palpation is - especially for obese patients - known to be error-prone, B-mode ultrasound (US) imaging could provide an alternative means. Several concepts of using ultrasound imaging to determine the APP landmarks have been introduced. In this paper we present a novel technique, which uses local patch statistical shape models (SSMs) and a hierarchical speed of sound compensation strategy for an accurate determination of the APP. These patches are independently matched and instantiated with respect to associated point clouds derived from the acquired ultrasound images. Potential inaccuracies due to the assumption of a constant speed of sound are compensated by an extended reconstruction scheme. We validated our method with in-vitro studies using a plastic bone covered with a soft-tissue simulation phantom and with a preliminary cadaver trial.

Slowdown of gist perception in colour diagnostic scenes

Humans perceive the content (gist) of a scene very rapidly within about 40 ms [Castelhano and Henderson, 2008 Journal of Experimental Psychology Human Perception and Performance 43(3) 660-675]. It has also been demonstrated that colours contribute to the perception of the gist of a scene if the colours are diagnostic for the distinction of scenes (Oliva and Schyns, 2000 Cognitive Psychology 41 176-210). We presented 320 coloured photographs of 2 diagnostic (mountains and coasts) and 2 nondiagnostic colour scenes (cities and rooms), 80 per category, in a masking paradigm. The mask consisted of randomly distributed colour patches. SOA was varied between 20 and 80 ms, in steps of 20 ms and subjects had to indicate the gist of the scene (4AFC). A control condition without masking was also included. In line with previous results we have found that the gist of nondiagnostic coloured scenes is extracted within 40 ms. However, if colour comes into play, the extraction of the scene gist is prolonged by about 20 ms. A possible reason for this outcome might be that nondiagnostic colour scenes are identified by their luminance components which are processed faster than the colour information, which in turn mediates the identification of diagnostic colour scenes

Core-crosslinked compartmentalized cylinders

We present a detailed study on the preparation of compartmentalized cylindrical nanoparticles via a templated approach: the polybutadiene part of a linear polybutadiene-block-poly(2-vinyl pyridine)-block-poly(tert-butyl methacrylate) block terpolymer, B420V280T790, having a bulk microstructure with PB cylinders covered by a P2VP double helix and embedded in a PtBMA matrix was selectively crosslinked. Subsequent sonication-assisted dissolution and chemical modifications such as quaternization (P2VP to P2VPq) and ester hydrolysis (PtBMA to poly(sodium methacrylate), PMANa) resulted in core-crosslinked cylinders soluble in organic and aqueous media. Different amounts of crosslinker and the influence of the sonication treatment on size and shape of the cylindrical aggregates were investigated. The cylinders always exhibit a compartmentalized corona. Under certain conditions, in particular quaternization of P2VP in mixtures of THF and MeOH, the helical arrangement of the P2VPq shell could be preserved even in solution, whereas in most other cases randomly distributed P2VP/P2VPq patches were observed. In aqueous solution at high pH, intramicellar interpolyelectrolyte complex (im-IPEC) formation occurred between the positively charged P2VPq shell and the negatively charged PMANa corona. We further show that different noble metal nanoparticles can be generated either selectively within the im-IPEC compartments (Pd) or randomly distributed among shell and corona of the cylinders (Au and Pt).

[Imaging diagostics of geographic atrophy]

The development of imaging technologies has contributed to the understanding of the genesis and pathophysiological mechanisms of geographic atrophy (GA) secondary to age-related macular degeneration (AMD). Fundus autofluorescence (FAF) imaging allows accurate discrimination of the boundaries of atrophic patches. Furthermore, predictive markers for disease progression can be identified. Non-invasive FAF imaging now represents the gold standard for evaluating progressive enlargement of atrophic areas. By means of high resolution optical coherence tomography (OCT) microstructural retinal changes in GA can be identified. Anatomical endpoints are now being used in interventional GA trials and represent meaningful outcome parameters as surrogate markers in an overall slowly progressive disease which may not affect the fovea until later stages of the disease.

Habitat-specific demography and source-sink dynamics in a population of Siberian jays

P>1. There are a number of models describing population structure, many of which have the capacity to incorporate spatial habitat effects. One such model is the source-sink model, that describes a system where some habitats have a natality that is higher than mortality (source) and others have a mortality that exceeds natality (sink). A source can be maintained in the absence of migration, whereas a sink will go extinct. 2. However, the interaction between population dynamics and habitat quality is complex, and concerns have been raised about the validity of published empirical studies addressing source-sink dynamics. In particular, some of these studies fail to provide data on survival, a significant component in disentangling a sink from a low quality source. Moreover, failing to account for a density-dependent increase in mortality, or decrease in fecundity, can result in a territory being falsely assigned as a sink, when in fact, this density-dependent suppression only decreases the population size to a lower level, hence indicating a 'pseudo-sink'. 3. In this study, we investigate a long-term data set for key components of territory-specific demography (mortality and reproduction) and their relationship to habitat characteristics in the territorial, group-living Siberian jay (Perisoreus infaustus). We also assess territory-specific population growth rates (r), to test whether spatial population dynamics are consistent with the ideas of source-sink dynamics. 4. Although average mortality did not differ between sexes, habitat-specific mortality did. Female mortality was higher in older forests, a pattern not observed in males. Male mortality only increased with an increasing amount of open areas. Moreover, reproductive success was higher further away from human settlement, indicating a strong effect of human-associated nest predators. 5. Averaged over all years, 76% of the territories were sources. These territories generally consisted of less open areas, and were located further away from human settlement. 6. The source-sink model provides a tool for modelling demography in distinct habitat patches of different quality, which can aid in identifying key habitats within the landscape, and thus, reduce the risk of implementing unsound management decisions.

Anti-idiotypic Fab Fragments Image a Conserved N-terminal Epitope Patch of Grass Pollen Allergen Phl p 1

BACKGROUND AND AIMS: Naturally occurring anti-idiotypic antibodies structurally mimic the original antibody epitope. Anti-idiotypes, therefore, are interesting tools for the portrayal of conformational B-cell epitopes of allergens. In this study we used this strategy particularly for major timothy grass pollen (Phleum pratense) allergen Phl p 1. METHODS AND RESULTS: We used a combinatorial phage display library constructed from the peripheral IgG repertoire of a grass pollen allergic patient which was supposed to contain anti-idiotypic Fab specificities. Using purified anti-Phl p 1 IgG for biopanning, several Fab displaying phage clones could be isolated. 100 amplified colonies were screened for their binding capacity to anti-Phl p 1-specific antibodies, finally resulting in four distinct Fab clones according to sequence analysis. Interestingly, heavy chains of all clones derived from the same germ line sequence and showed high homology in their CDRs. Projecting their sequence information on the surface of the natural allergen Phl p 1 (PDB ID: 1N10) indicated matches on the N-terminal domain of the homo-dimeric allergen, including the bridging region between the two monomers. The resulting epitope patches were formed by spatially distant sections of the primary allergen sequence. CONCLUSION: In this study we report that anti-idiotypic specificities towards anti-Phl p 1 IgG, selected from a Fab library of a grass pollen allergic patient, mimic a conformational epitope patch being distinct from a previously reported IgE epitope area.