Psychopathological symptoms of depression in Parkinson's disease compared to major depression

Parkinson's disease is frequently associated with depressive symptoms. When depression occurs at early stages and before the onset of characteristic motor symptoms of the disease, differential diagnosis of major depression may be difficult. Differences in psychopathological features of depression in Parkinson's disease and major depression have been reported by some authors. This study presents data of 49 patients with depression in Parkinson's disease and 38 patients with major depression. Severity of depressive symptoms was equivalent in both groups. Depressive features did not differ between the two groups with exception of affective flattening, delusional ideas and suicide attempts. In conclusion, this investigation gives support to the assumption of a common neurobiological origin of depression in Parkinson's disease and major depression

Self-assembly of Silver Nanoparticles and Multiwall Carbon Nanotubes on Decomposed GaAs Surfaces

Atomic Force Microscopy complemented by Photoluminescence and Reflection High Energy Electron Diffraction has been used to study self-assembly of silver nanoparticles and multiwall carbon nanotubes on thermally decomposed GaAs (100) surfaces. It has been shown that the decomposition leads to the formation of arsenic plate-like structures. Multiwall carbon nanotubes spin coated on the decomposed surfaces were mostly found to occupy the depressions between the plates and formed boundaries. While direct casting of silver nanoparticles is found to induce microdroplets. Annealing at 300°C was observed to contract the microdroplets into combined structures consisting of silver spots surrounded by silver rings. Moreover, casting of colloidal suspension consists of multiwall carbon nanotubes and silver nanoparticles is observed to cause the formation of 2D compact islands. Depending on the multiwall carbon nanotubes diameter, GaAs/multiwall carbon nanotubes/silver system exhibited photoluminescence with varying strength. Such assembly provides a possible bottom up facile way of roughness controlled fabrication of plasmonic systems on GaAs surfaces

Object-based image analysis: Evolution, history, state of the art, and future vision

Remote sensing, what it is and what it can be used for, is laid out in various chapters of this comprehensive book. We may only state here that remote sensing has a short history-when compared to traditional disciplines such as mathematics or physics. Contrarily, we may state that it has a long history when we compare it to recent Internet-based technology like social media or, closer to our field, the tracking of people and moving objects by means of cell phone signals. Remote sensing has been a domain for specialists for many years and to some degree it still is. Similarly, geographic information system (GIS) has for years been a field where professionals worked on designated workstations while not being fully integrated in standard corporate information technology infrastructures. The latter changed more than a decade ago, while for remote sensing only recently, one may still witness remnants of historical developments of Remote Sensing (RS)-specific hardware and software. The dominant concept in remote sensing has been the pixel, while GIS functionality has always been somehow splintered into the raster and vector domains. Blaschke and Strobl (2001) provocatively raised the question “What's wrong with pixels?” having identified an increasing dissatisfaction with pixelby-pixel image analysis. Although this critique was not new (Cracknell 1998; see also Blaschke and Strobl 2001; Burnett and Blaschke 2003; Blaschke 2010; Blaschke et al. 2014 for a more thorough discussion), these authors described a need for applications beyond pixels and for specific methods and methodologies that support this (Figure 14.1)

Collective and single-particle dynamics in time-resolved two-photon photoemission

Merschdorf M, Kennerknecht C, Pfeiffer W. Collective and single-particle dynamics in time-resolved two-photon photoemission. Physical Review B. 2004;70(19): 193401.A general model for time-resolved two-photon photoemission from solids is presented comprising both collective and single-electron dynamics. In combination with interferometric time-resolved two-photon photoemission, this allows one to determine the shape of the collective response function across the excitation spectrum and the single-particle lifetime of excited electrons. Ag nanoparticles supported on graphite exhibit a strong collective resonance and serve as model system to demonstrate experimentally this separation of collective and single-particle dynamics in two-photon photoemission

Electron gas cooling in Ag nanoparticles on graphite

Merschdorf M, Pfeiffer W, Voll S,, Gerber G. Electron gas cooling in Ag nanoparticles on graphite. Phys. Rev. B. 2003;68(15): 155416

Hot electron tunneling in femtosecond laser-assisted scanning tunneling microscopy

Merschdorf M, Pfeiffer W, Thon A, Gerber G. Hot electron tunneling in femtosecond laser-assisted scanning tunneling microscopy. Applied Physics Letters. 2002;81(2):286-288.The combination of scanning tunneling microscopy with femtosecond laser spectroscopy yields simultaneously ultimate spatial and temporal resolution. One possibility to realize this combination is the direct excitation of the tunnel junction in a pump-probe configuration and the detection of a tunnel current component that depends nonlinearly on the laser intensity. The laser-induced signal is expected to be very small, therefore a suitable sample material and a modulation technique is required. In measurements on a GaP(100) surface evidence for tunneling of hot electrons is obtained giving the possibility for local time-resolved tunneling spectroscopy. (C) 2002 American Institute of Physics

Identification of multiphoton induced photocurrents in metal-insulator-metal junctions

Diesing D, Merschdorf M, Thon A, Pfeiffer W. Identification of multiphoton induced photocurrents in metal-insulator-metal junctions. Appl. Phys. B. 2004;78(3-4):443-446

Transient electron energy distribution in supported Ag nanoparticles

Merschdorf M, Kennerknecht C, Willig K, Pfeiffer W. Transient electron energy distribution in supported Ag nanoparticles. New Journal of Physics. 2002;4(1):95.The electron relaxation in Ag nanoparticles supported on graphite is investigated by time- resolved multiphoton photoemission spectroscopy. The photoemission spectra map the transient electron energy distribution in the nanoparticles and reveal the internal thermalization and cooling of the electron gas. The excess energy stored in the electron gas is calculated using the free-electron model. In contrast to the behaviour of isolated nanoparticles the energy loss rate from the electron gas increases with the pump fluence. This indicates that the electron gas equilibration in Ag nanoparticles on graphite is modified by excited electron transport

Surface plasmon assisted photoemission from Au nanoparticles on graphite

Kennerknecht C, Hövel H, Merschdorf M, Voll S, Pfeiffer W. Surface plasmon assisted photoemission from Au nanoparticles on graphite. Appl. Phys. B. 2001;73(4):425-429