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Iwamizawa, Japan

Pawlikowski P.,University of Warsaw | Abramczyk K.,University of Warsaw | Szczepaniuk A.,University of Warsaw | Szczepaniuk A.,Nature Technology | Kozub L.,University of Warsaw

The species composition of 22 mires (brown-moss rich fens) was surveyed in north-eastern Poland, located in continental boreo-nemoral Europe. Detailed analyses of the water chemistry, biomass N, P, and K content, productivity and water level were made. Two floristically different types of richfen vegetation occur in this area, one with numerous Caricetalia davallianae (calcicole) species such as Scorpidium cossonii, Campylium stellatum, Carex lepidocarpa and Eriophorum latifolium (Cd fens) and the other with a few Caricetalia davallianae species and mainly Hamatocaulis vernicosus, Marchantia polymorpha, Plagiomnium ellipticum, Carex diandra and C. rostrata (non- Cd fens). In these two rich-fen types surface water chemistry and water levels were similar, but the Cd fens characteristically had higher pHs and lower PO4 3- concentrations. N and P availability revealed by the N:P ratio is the ecological factor that best accounts for the differences in species composition of the two rich-fen types: the non-Cd fens are N-limited while the Cd-fens are usually P-limited. Moreover, the Cd fens differ from the non-Cd fens in a higher productivity of the bryophyte layer. In the case of P andKconcentrations, there is a correlation between that in vascular plants and bryophytes, while N concentrations are not correlated.We believe that in the case of low productive ecosystems the use of the broad "nutrient availability gradient" should be replaced by a (from) N-(to) P-limitation gradient with N:P ratio as a useful measure. Natural N-limited, lowproductive rich fens and their ecological conditions can be a phenomenon typical of continentaleastern temperate European areas, which have been poorly surveyed and need further research. Source

Jablonska E.,University of Warsaw | Pawlikowski P.,University of Warsaw | Jarzombkowski F.,Nature Technology | Chormanski J.,Warsaw University of Life Sciences | And 2 more authors.

Although conservation of percolation mires is very important for the European biodiversity, our understanding of their functioning is still insufficient, as most of the studied sites are to some extent degraded. We present a study on the relationship between vegetation patterns, hydrochemical gradients and water level fluctuations carried out in the Rospuda valley (NE Poland), which was recently discovered for science as a uniquely preserved fully functioning percolation mire. Vegetation composition, mire water chemistry and water level dynamics were studied along five transects perpendicular to the valley. Eight major vegetation types were identified: brown moss-small and slender sedge fens, Sphagnum-small sedge fens, brown moss-tall sedge fens, tall sedge-reed fens, pine-birch fen woodlands and shrublands, spruce fen woodlands, inundated alder woodlands, alder spring fen woodlands. The seasonal dynamics of water table was revealed as the major factor explaining vegetation patterns. The studied chemical parameters were relatively homogeneous in the whole mire-there is a rather uniform type of mineral-rich nutrient-poor subsurface water all across the fen. © 2011 The Author(s). Source

Tryka S.,Lublin University of Life Sciences | Tryka S.,Nature Technology
Journal of Modern Optics

The multidomain integral equation method is used to calculate fluxes of radiation from various on- and off-axis point sources passing through two different homogeneous isotropic media and striking a surface of a circular disc perpendicular to the optical axes of these sources. This method is dedicated to radiation passing through attenuating or nonattenuating media with a Fresnel interface and is applicable for arbitrary radiation patterns of point sources. The paper presents, firstly, the generalized multidomain integral equation method, expressed by double iterated integrals, for calculating radiant fluxes from arbitrary emitting point sources. This generalized method is simplified then to the form of multidomain single integral equation method applicable for rotationally symmetrical radiation patterns with optical axes perpendicular to the disc. Next, the simplified method is used for computer simulation of radiant fluxes incident on the disc from small Lambertian and Gaussian sources represented by point source models. All numerical results obtained from this simulation have shown high accuracy and efficiency of the presented method. Selected results are illustrated graphically and validated by Optical Software for Layout and Optimization (OSLO) from Lambda Research Corporation. Potential applications of the presented method include optical sensing and metrology, optical coupling, immersion microscopes, light-extraction problems and creative lighting design. © 2014 Taylor & Francis. Source

Optical systems protected by plane-parallel entrance windows from external environmental conditions were studied to determine the radiant fluxes passing through their circular apertures from wide-angle on-axis and off-axis point sources. The study was performed for the case when the windows, the internal environments, and the external environments of these optical systems were considered as three different homogeneous isotropic and attenuating media. All considerations were made for ideal plane-parallel windows illuminated by an arbitrary radiation field applying the multiple-reflection theory. As a result of this study a multi-domain integral equation method based on a mathematical formula expressed by a series of multiple-reflected fluxes of radiation within the plane-parallel window was proposed. The applicability of the method was tested using computer simulations for an isotropic point source and a small area Lambertian source represented by a point-source model. The computed results were validated by the optical software for layout and optimization program from Lambda Research Corporation (USA). The selected results were illustrated graphically and analyzed. The numerical simulations have shown high accuracy and efficiency in the calculations for arbitrary emitting point sources. The potential applications of the presented method include optical sensing and metrology of noncollimated radiation from the various on-axis and off-axis point sources. © 2015 Optical Society of America. Source

Suttrup I.,University of Munster | Oberdiek D.,University of Munster | Suttrup J.,Nature Technology | Osada N.,University of Munster | And 2 more authors.
Movement Disorders

Former studies suggest an additional involvement of the sensory nervous system, beside the involuntary contractions of antagonist muscles, in idiopathic hand dystonia. We studied contact heat-evoked potentials and quantitative sensory testing (QST) in 10 patients suffering from idiopathic hand dystonia and 10 age-matched healthy controls. Cortical potentials recorded from the vertex (Pz) after contact heat stimulation of the volar forearm and the dorsum of the hand at a temperature of 51°C showed significantly reduced A-δ-amplitudes. Numerical pain ratings on the affected side in comparison to the unaffected side and to healthy controls were significantly reduced. QST results showed an impairment of the thermal detection thresholds, the mechanical pain sensitivity and the mechanical pain threshold at the affected body side of the patients. Our results suggest a loss of distinct sensory functions of the affected hand in comparison with the contralateral hand and to matched healthy subjects in patients suffering from idiopathic hand dystonia. For the first time, an extended loss of sensory function could be shown in patients suffering from idiopathic hand dystonia. © 2010 Movement Disorder Society. Source

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