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Sample records for kadastik volli kalm

  1. Re-introduction of kava (Piper methysticum) to the EU: is there a way forward?

    PubMed

    Sarris, Jerome; Teschke, Rolf; Stough, Con; Scholey, Andrew; Schweitzer, Isaac

    2011-01-01

    Kava (Piper methysticum) is an effective anxiolytic that has been withdrawn from various consumer markets in European countries due to concerns over its hepatotoxicity. It is plausible that the reported hepatotoxicity may be due in part to plant substitution, or an incorrect cultivar, or plant parts being used (such as leaves or bark); thus both the plant chemotype and the plant part used may be critical factors. If re-institution of kava in the EU is to occur, more evidence is required to determine its safety and efficacy. Furthermore, according to current evidence, the study of traditional water soluble rhizome extracts using a noble cultivar of kava may be advised. The Kava Anxiety-Lowering Medication (KALM) project is due to start in late 2010 to address these considerations. The KALM project uses an aqueous rhizome extract of a noble cultivar of kava in participants with generalised anxiety and Generalised Anxiety Disorder (GAD). The project comprises of 1) an acute RCT, kava (180 mg of kavalactones) versus oxazepam and placebo in 20 anxious people, testing effects on cognition, mood, anxiety, and driving; 2) an 8-week RCT comparing kava (120 mg kavalactones) versus placebo in 100 patients with GAD. To assess differences between dosages, non-responders at 3 weeks will be titrated to 240 mg of kavalactones. The project will also assess the effects of kava on liver function tests and its side effects profile. A novel component of the project is the pharmacogenomic exploration of phenotypical responses (GABA system and cytochrome P450 markers). The results of the study may be of benefit to sufferers of anxiety and the future economy of the Pacific islands, potentially providing an important step in the way forward with kava.

  2. Micromorphological difference between glacial and glaciofluvial quartz grain, evidence from Svalbard

    NASA Astrophysics Data System (ADS)

    Krbcová, Klára

    2017-04-01

    Micromorphology of glaciofluvial sediments were only partially shown by Mahaney et al. (2001). This paper deals with the main diagnostic textures of glaciofluvial sediments and changes of their micromorphology caused fluvial transport. All samples were collected in Svalbard in August 2012. Two glacial samples and six glaciofluvial samples were taken near the glacier Bertilbreen and one glacial sample and seven glaciofluvial samples were taken near the glacier Hørbyebreen. Samples were prepared according to the Mahaney (2002) and examined under electron microscope. The correlation analyses was used to set the main glaciofluvial microtextures. Similarity of the samples was tested by one-way ANOVA by F-test. Increasing numbers of V-shaped pits, rounded grains, meandering ridges and microblocks are typical for characteristic microtextures of glaciofluvial grains which had greater rate of fluvial transport. But the grains mainly transported by glacier had a greater percentage occurence of subangular grains, straight steps, straight and curved grooves, adhering particles, pitting and V-shaped etch pits. The fastest change in variability was set during the first kilometre of fluvial transport. The study was funded by the Grant Agency of Charles University (GAUK 1314214). Keywords: exoscopy, quartz grains micromorphology, glaciofluvial sediments References: MAHANEY, W. C. (2002): Atlas of sand grain surface textures and applications. Oxford University Press, USA, 237 s. MAHANEY, W. C., STEWART A., KALM, V. (2001): Quantification of SEM microtextures useful in sedimentary environmental discrimination. Boreas, 30, s. 165 - 171.

  3. Single-Crystal Elastic Properties of the Spinel (MgAl2O4) - Galaxite (MnAl2O4) Solid Solution Series

    NASA Astrophysics Data System (ADS)

    Speziale, S.; Bruschini, E.; Andreozzi, G. B.; Bosi, F.; Hålenius, U.

    2014-12-01

    Spinels are a subject of intense research in solid state physics, materials science and geosciences. Their general formula is T(A1-i)M(AiB2-i)X4 (A and B are cations, X are anions, T and M indicate tetrahedrally- and octahedrally-coordinated sites and i is the inversion degree). They are ideal materials to study the interplay between chemical substitutions, structure and the physical properties of solids. As spinel-structured ringwoodite (Mg,Fe)2SiO4 is the most abundant mineral in the lower transition zone, understanding the effect of chemical substitution on the elastic properties of spinels is of crucial for geophysics. We have experimentally studied the variation of the elastic properties along the join MgAl2O4 - MnAl2O4. Crystals of 4 compositions along the join were synthesized at the very same experimental conditions and their crystal chemistry was fully characterized. Single-crystal elastic constants Cij of all the samples were measured by Brillouin spectroscopy at ambient conditions. For compositions with Mn/Mg < 0.5 C11 remains constant, then it decreases of ~4% for higher Mn contents. From MgAl2O4 to MnAl2O4 C12 lineraly increases ~ 5% and C44 decreases ~ 20% . The bulk modulus KS is almost constant, whereas the shear modulus G decreases ~ 18% across the join. The elastic constants of MnAl2O4 are C11 = 271.3 (± 1.3) GPa, C12 = 164.8 (± 1.3) GPa and C44 = 124.9 (5) GPa. Using the empirical polyhedral approach [1] we have inferred the effectve polyhedral bulk moduli of Mg, Mn and Al in T and M sites. We observe that KMnM < KMgM < KMgT ≈ KMnT < KAlM << KAlT. The relationship between polyhedral moduli and ionic potential IP [2] can be expressed as Ki j (GPa) = 20 ( ± 2) × IP + 108 (± 10), where i is the cation, j is the site and IP is in units of (e/Å). Using our correlation and atomic radii from [3] we successfully reproduced the bulk modulus of different oxide spinels with bi- and tri-valent cations. Our preliminary results confirm that empirical

  4. Analysis of the varved clay accumulation in the Pärnu Bay area, Estonia

    NASA Astrophysics Data System (ADS)

    Kalvans, Andis; Hang, Tiit

    2015-04-01

    solely by the basin depth and duration of the ice cover period. A normal grading is observed in most of the studied winter layers of individual varves. Relatively large errors in the estimated terminal grain size permits only to conclude that it is in line with previously reconstructed water depth constrained by the maximum possible duration of the lake ice cover. The research is supported by the European Union through the ESF Mobilitas grant No MJD309. References Hang, T., Kohv, M. 2013. Glacial varves at Pärnu, south-western Estonia: a local varve chronology and proglacial sedimentary environment. GFF, June, 37-41. doi:10.1080/11035897.2013.775598 Rosentau, A., Vassiljev, J., Hang, T., Saarse, L., Kalm, V. 2009. Development of the Baltic Ice Lake in the eastern Baltic. Quaternary International, 206(1-2), 16-23. doi:10.1016/j.quaint.2008.10.005