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Sample records for erki laiakask mihkel

  1. Precise Head Tracking in Hearing Applications

    NASA Astrophysics Data System (ADS)

    Helle, A. M.; Pilinski, J.; Luhmann, T.

    2015-05-01

    The paper gives an overview about two research projects, both dealing with optical head tracking in hearing applications. As part of the project "Development of a real-time low-cost tracking system for medical and audiological problems (ELCoT)" a cost-effective single camera 3D tracking system has been developed which enables the detection of arm and head movements of human patients. Amongst others, the measuring system is designed for a new hearing test (based on the "Mainzer Kindertisch"), which analyzes the directional hearing capabilities of children in cooperation with the research project ERKI (Evaluation of acoustic sound source localization for children). As part of the research project framework "Hearing in everyday life (HALLO)" a stereo tracking system is being used for analyzing the head movement of human patients during complex acoustic events. Together with the consideration of biosignals like skin conductance the speech comprehension and listening effort of persons with reduced hearing ability, especially in situations with background noise, is evaluated. For both projects the system design, accuracy aspects and results of practical tests are discussed.

  2. Chemical composition and anti-inflammatory activity of Chamaecyparis obtusa f.formosana wood essential oil from Taiwan.

    PubMed

    Chien, Tzu-Chao; Lo, Sheng-Fong; Ho, Chen-Lung

    2014-05-01

    Chamaecyparis obtusa Siebold & Zucc. f.formosana Hayata (Cupressaceae) is one of the treasured conifers in Taiwan. In this study, the wood essential oil of the species was extracted and its anti-inflammatory bioactivities analyzed. The composition analysis of the essential oil yielded a total of 57 compounds with alpha-terpineol (19.4%), tau-muurolol (16.9%), borneol (16%), and alpha-cadinol (10.9%) predominating. The anti-inflammatory assays of the essential oil suggest that C obtusa f. formnosana wood oil has no cytotoxicity, and was capable of inhibiting the expressions of tumor necrosis factor (TNF-alpha), IL-6, IL-1, pro IL-1beta, NO, iNOS, and NLRP3 in murine macrophage cells. It was unable, however, to inhibit the expression of COX-2. Further investigation of the effect of the essential oil on the cellular signal transduction indicated that it was capable of inhibiting ERKI/2, JNKI/2 and p38; it also showed excellent inhibition against ROS. Thus, the overall results indicated that C. obtusa f.formnosana wood oil had very good anti-inflammatory efficacies.

  3. A novel role for extracellular signal-regulated kinase in maintaining long-term memory-relevant excitability changes.

    PubMed

    Cohen-Matsliah, Sivan Ida; Brosh, Inbar; Rosenblum, Kobi; Barkai, Edi

    2007-11-14

    Pyramidal neurons in the piriform cortex from olfactory-discrimination-trained rats show enhanced intrinsic neuronal excitability that lasts for several days after learning. Such enhanced intrinsic excitability is mediated by long-term reduction in the postburst afterhyperpolarization (AHP), which is generated by repetitive spike firing. AHP reduction is attributable to decreased conductance of a calcium-dependent potassium current, the sI(AHP). We have previously shown that such learning-induced AHP reduction is maintained by PKC activation. However, the molecular machinery underlying such long-lasting modulation of intrinsic excitability is yet to be fully described. Here we examine whether the extracellular signal-regulated kinase I/II (ERKI/II) pathway, which is known to be crucial in learning, memory, and synaptic plasticity processes, is instrumental for the long-term maintenance of learning-induced AHP reduction. PD98059 or UO126, which selectively block MEK, the upstream kinase of ERK, increased the AHP in neurons from trained rats but not in neurons from naive and pseudo-trained rats. Consequently, the differences in AHP amplitude and neuronal adaptation between neurons from trained rats and controls were abolished. This effect was not mediated by modulation of basic membrane properties. In accordance with its effect on neuronal excitability, the level of activated ERK in the membranal fraction was significantly higher in piriform cortex samples taken from trained rats. In addition, the PKC activator OAG (1-oleoyl-20acety-sn-glycerol), which was shown to reduce the AHP in neurons from control rats, had no effect on these neurons in the presence of PD98059. Our data show that ERK has a key role in maintaining long-lasting learning-induced enhancement of neuronal excitability.

  4. The preliminary results of larger foraminifera analysis from the Paleocene-Early Eocene of Southern Yemen, based on museums collections

    NASA Astrophysics Data System (ADS)

    Zakrevskaya, E.

    2012-04-01

    The recent work is based on collections, which were sampled in 1980-th by soviet geologists and preserving now in funds of Vernadsky State Geological Museum. They include litological samples with larger foraminifera (LF) and separated tests of LF from Paleogene of Atag area and Hadramaut plateau (Souternn Yemen). The planctonic foraminifera are very rare in considered samples. According to lithological and foraminiferal composition all samples (about 100 numbers) are divided into three parts. The first one includes the LF tests, washed from sandy marls and shales of wells. The second unit represented by bioclastic limestones, partly silicified and dolomitized and rare marls, collected from the exposed sections. These units belong to Umm er Radhuma formation, which in Yemen dated by Paleocene-Eocene (Pignatti et al., 1998) or only Eocene (Ismail and Boukhary, 2008). The third, Lower Eocene unit in collections (Jeza formation) represented mainly by non carbonatic, gypsiferous argillaceous papery shales and marls. The most lower, marly part of section is opened by wells. The LF assemblages from marls of wells include the next rotaliids in lower part: Lokhartia lobulata Sander, L. haimei spirahordata Sander, L. cf. conditi Smout, Rotalia sp., Diktiokathina sp. The rests of Saudia tests are rare. In upper part Kathina erki (Sirel), Rotalia dukhani Smout and first small nummulites are marked. The lasts belong to Nummulites deserti group, having smaller protoconch and more compressed spire. Due to absence of true Eocene forms we consider these assemblages as paleocenic. The next association, represented by abundant Lockhartia sp., Lockhartia diversa Smout, Sakesaria sp. and rare Daviesina khatyahi Smout, Operculina cf. ornata Hott. and established in hard limestones of Umm er Radhuma formation, identified as transitional from Paleocene to Eocene (Lower Ilerdian). In marls and shales, alternated with limestones in upper part of this formation the middle Ilerdian assemblage

  5. Pollen-inferred quantitative reconstructions of Holocene land-cover in NW Europe for the evaluation of past climate-vegetation feedbacks - The Swedish LANDCLIM project and the NordForsk LANDCLIM network

    NASA Astrophysics Data System (ADS)

    Gaillard, Marie-Jose; Sugita, Shinya; Rundgren, Mats; Smith, Benjamin; Mazier, Florence; Trondman, Anna-Kari; Fyfe, Ralph; Kokfelt, Ulla; Nielsen, Anne-Birgitte; Strandberg, Gustav

    2010-05-01

    of ca. 1o x 1o. The REVEALS estimates of the past cover of PFTs will be 1) compared with the outputs of the LPJ-GUESS (10 PFTs), a widely-used dynamic vegetation model and 2) used as an alternative to the LPJ-GUESS-simulated vegetation (3 PFTs) to run for the past the regional climate model RCA3 developed at the Rossby Centre, Norrköping, Sweden. The study will evaluate and further refine these models (RCA3 and LPJ-GUESS) using a data-model comparison approach that incorporates new syntheses of palaeoclimatic data as well. It will lead to new assessments of the possible effect of various factors on climate, such as deforestations and afforestations, and changes in vegetation composition and spatial patterns of land cover/land use. Refined climate models and empirical land-cover reconstructions will shed new light on controversial hypotheses of past climate change and human impacts, such as the "Ruddiman hypothesis". First maps of REVEALS estimates of plant functional types (PFTs) are now available for Sweden, Norway, Finland, Denmark, Estonia, Poland, Germany, The Czech Republic, Switzerland and Britain (see Mazier et al. C1.21 and Trondman et al. C1.22). Correlation tests show that the REVEALS estimates are robust in terms of ranking of the PFTs' abundance (see Mazier et al, C1.21). The LANDCLIM project and network are a contribution to the IGBP-PAGES-Focus 4 PHAROS programme on human impact on environmental changes in the past. The following LANDCLIM members are acknowledged for providing pollen records, for help with pollen databases, and for providing results to the project: Mihkel Kangur and Tiiu Koff (Univ. Tallinn, Tallinn); Erik Kjellström (SMHI, Norrköping), Anna Broström, Lena Barnekow and Thomas Persson (GeoBiosphere Science Centre, Lund University); Anneli Poska (Physical Geography and Ecosystems Analysis, Lund University); Thomas Giesecke (Albrecht-von-Haller-Institute for Plant Sciences, University of Göttingen), Anne Bjune and John Birks (Dept. of