Classification of New Zealand Arionacea (Mollusca : pulmonata). A revision of some endodontid genera (Endodontidae Pilsbry, 1894).

The following systematic revisions of New Zealand taxa within the Arionacean subfamilies Flammulininae Climo, 1969, Otoconchinae Cockerell, 1893 and Endodontinae Suter, 1913 (family Endodontidae Pilsbry, 1894) are based on quantitative reappraisals of shell morphology and studies on radular and soft-part morphology. The last major revision of these New Zealand pulmonate taxa was presented by Suter (1 913) i n his Manual of the New Zealand Mollusca, and illustrated in his Atlas of Plates which appeared in 1915. Suter’s work was, as were the great majority of earlier pulmonate systematic studies, based on studies of shell and radular morphology, and was the major contribution towards the erection of a systematic hierarchy which illustrated the indigenous nature of the New Zealand endodontid fauna. Systematic studies on Australian and New Zealand endodontids by the contemporary worker T. Iredale resulted in the replacement of Suter1s hierarchy which was influenced by the earlier works of H. A. Pilsbry. Iredale’s higher classification of the New Zealand endodontid fauna has been followed in Australia and New Zealand to the present day, but not without question. The introductory paper in the series which comprises this thesis elaborates on, and shows that the doubts held about the Iredalian higher systematics can be substantiated. I was influenced by statements made by Solem (1959) to undertake an anatomical study of the New Zealand representatives of the family Endodontidae Pilsbry, 1894. Solem and other workers have mentioned that the distinction between Charopidae Iredale, 1937 and Flammulinidae Iredale, 1937 was artificial. Solem also stated that to understand the generic relationships within the large, diverse group of molluscs which he classified in the redefined subfamily Endodontinae Suter, 1913 (Charopidae and Flammulinidae), anatomical studies would have to be undertaken. Having shown that the distinction between Charopidae and Flammulinidae was artificial (Part I), I then proceeded to systematically dissect all available New Zealand species within the redefined subfamily Endodontinae. The results of these dissections have provided information which enables the Endodontinae to be divided into two taxa: the subfamilies Endodontinae and Flarnmulininae Climo. Having established this higher systematic platform I then revised the existing taxa in light of the new anatomical data and information provided by studies in shell variation. The revisions as here presented are part of a long term study which will eventually result in a review of the entire New Zealand endodontid fauna. Lack of material and the time necessary to revise some genera in the Flammulininae, and the large punctid complex (Punctinae Morse, 1864) has made it impracticable to include a revision of these taxa in this thesis

Anisotropic excitation of surface plasmon polaritons on a metal film by a scattering-type scanning near-field microscope with a nonrotationally-symmetric probe tip

We investigated the excitation of surface plasmon polaritons on gold films with the metallized probe tip of a scattering-type scanning near-field optical microscope (s-SNOM). The emission of the polaritons from the tip, illuminated by near-infrared laser radiation, was found to be anisotropic and not circularly symmetric as expected on the basis of literature data. We furthermore identified an additional excitation channel via light that was reflected off the tip and excited the plasmon polaritons at the edge of the metal film. Our results, while obtained for a non-rotationally-symmetric type of probe tip and thus specific for this situation, indicate that when an s-SNOM is employed for the investigation of plasmonic structures, the unintentional excitation of surface waves and anisotropic surface wave propagation must be considered in order to correctly interpret the signatures of plasmon polariton generation and propagation

Early-Onset and Robust Amyloid Pathology in a New Homozygous Mouse Model of Alzheimer's Disease

BACKGROUND: Transgenic mice expressing mutated amyloid precursor protein (APP) and presenilin (PS)-1 or -2 have been successfully used to model cerebral beta-amyloidosis, one of the characteristic hallmarks of Alzheimer's disease (AD) pathology. However, the use of many transgenic lines is limited by premature death, low breeding efficiencies and late onset and high inter-animal variability of the pathology, creating a need for improved animal models. Here we describe the detailed characterization of a new homozygous double-transgenic mouse line that addresses most of these issues. METHODOLOGY/PRINCIPAL FINDINGS: The transgenic mouse line (ARTE10) was generated by co-integration of two transgenes carrying the K670N/M671L mutated amyloid precursor protein (APP(swe)) and the M146V mutated presenilin 1 (PS1) both under control of a neuron-specific promoter. Mice, hemi- as well as homozygous for both transgenes, are viable and fertile with good breeding capabilities and a low rate of premature death. They develop robust AD-like cerebral beta-amyloid plaque pathology with glial inflammation, signs of neuritic dystrophy and cerebral amyloid angiopathy. Using our novel image analysis algorithm for semi-automatic quantification of plaque burden, we demonstrate an early onset and progressive plaque deposition starting at 3 months of age in homozygous mice with low inter-animal variability and 100%-penetrance of the phenotype. The plaques are readily detected in vivo by PiB, the standard human PET tracer for AD. In addition, ARTE10 mice display early loss of synaptic markers and age-related cognitive deficits. By applying a gamma-secretase inhibitor we show a dose dependent reduction of soluble amyloid beta levels in the brain. CONCLUSIONS: ARTE10 mice develop a cerebral beta-amyloidosis closely resembling the beta-amyloid-related aspects of human AD neuropathology. Unifying several advantages of previous transgenic models, this line particularly qualifies for the use in target validation and for evaluating potential diagnostic or therapeutic agents targeting the amyloid pathology of AD

Completion of the 8 MW Multi-Frequency ECRH System at ASDEX Upgrade

Over the last 15 years, the Electron Cyclotron Resonance Heating (ECRH) system at the ASDEX Upgrade tokamak has been upgraded from a 2 MW, 2 s, 140 GHz system to an 8 MW, 10 s, dual frequency system (105/140 GHz). Eight gyrotrons were in routine operation during the current experimental campaign. All gyrotrons are step-tunable operating at 105 and 140 GHz with a maximum output power of about 1 MW and 10 s pulse length. The system includes 8 transmission lines, mainly consisting of oversized corrugated waveguides (I.D. = 87 mm) with overall lengths between 50 and 70 meters including quasi-optical sections at both ends. Further improvements of the transmission lines with respect to power handling and reliability are underway

Impact of buffer gas quenching on the S-1(0) -> P-1(1) ground-state atomic transition in nobelium

International audienceUsing the sensitive Radiation Detected Resonance Ionization Spectroscopy (RADRIS) techniquean optical transition in neutral nobelium (No, Z = 102) was identified. A remnant signal when delaying the ionizing laser indicated the influence of a strong buffer gas induced de-excitation of the optically populated level. A subsequent investigation of the chemical homologue, ytterbium (Yb, Z = 70), enabled a detailed study of the atomic levels involved in this process, leading to the development of a rate equation model. This paves the way for characterizing resonance ionization spectroscopy (RIS) schemes used in the studyof nobelium and beyond, where atomic properties are currently unknown

Exploring fusion-reactor physics with high-power electron cyclotron resonance heating on ASDEX Upgrade

The electron cyclotron resonance heating (ECRH) system of the ASDEX Upgrade tokomak has been upgraded over the last 15 years from a 2MW, 2 s, 140 GHz system to an 8MW, 10 s, dual frequency system (105/140 GHz). The power exceeds the L/H power threshold by at least a factor of two, even for high densities, and roughly equals the installed ion cyclotron range of frequencies power. The power of both wave heating systems together (>10MW in the plasma) is about half of the available neutral beam injection (NBI) power, allowing significant variations of torque input, of the shape of the heating profile and of Qe/Qi, even at high heating power. For applications at a low magnetic field an X3-heating scheme is routinely in use. Such a scenario is now also forseen for ITER to study the first H-modes at one third of the full field. This versatile system allows one to address important issues fundamental to a fusion reactor: H-mode operation with dominant electron heating, accessing low collisionalities in full metal devices (also related to suppression of edge localized modes with resonant magnetic perturbations), influence of Te/Ti and rotational shear on transport, and dependence of impurity accumulation on heating profiles. Experiments on all these subjects have been carried out over the last few years and will be presented in this contribution. The adjustable localized current drive capability of ECRH allows dedicated variations of the shape of the q-profile and the study of their influence on non-inductive tokamak operation (so far at q$_{95}$>5.3). The ultimate goal of these experiments is to use the experimental findings to refine theoretical models such that they allow a reliable design of operational schemes for reactor size devices. In this respect, recent studies comparing a quasi-linear approach (TGLF) with fully non-linear modeling (GENE) of non-inductive high-beta plasmas will be reported