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Psihoemocionālie riski montāžas darbiniekam eksporta būvobjektos ārkārtas situācijas laikā
2022
Darba autors Emīls Beitiņš izstrādājis Bakalaura darbu par tēmu – “Psihoemocionālie riski montāžas darbiniekam eksporta būvobjektos ārkārtas situācijas laikā”. Darba kopējais apjoms 60 lpp, rezultāti apkopoti 7 tabulās, ievietoti 27 attēli. Darba izstrādāšanai izmantoti 25 literatūras avoti. Bakalaura darba mērķis ir apzināties pasākumu kopumu darba devējam, lai samazinātu psihoemocionālu stresu darbiniekam atrodoties ārvalstī ārkārtas situācijas laikā, kad nav zināma tuvākā iespēja atgriezties mājās pie ģimenes. Bakalaura darba uzdevums: Apzināties kādus pasākums uzņēmums varētu ieviest nākotnē, lai samazinātu darbinieku psiholoģisko stresu, kā arī apzināties cik lielu psiholoģisko stresu …
De la performance musicale dans la Guyane traditionnelle : expression cognitive singulière d?une musique-verbe
2021
Guianese culture and traditional music, here evoked, are various. It is more a transcultural process that, along centuries, gave an original result born in the Americas, in Guiana in this case. It is a form of refoundation, of recreation of cultures and new human beings generally called Creoles. The musical performance, that I study here, is the echo of social and cultural space of this reformulation of thought, life, and conception of the world. It is, as well, a mean of transposition and transformation of the values issued of diverse sources and categories. It is in no way a second-rate cultural practice, as it is the place where were born philosophies and actions for common life as well …
Covid-19 : quel bilan critique ? (Partie II)
2021
International audience
Reactivity of Distibanes toward Trialkylalanes and -gallanes: Syntheses and X-ray Structures of Bisadducts and Heterocycles
2001
Reactions between distibanes of the type Sb2R4 and trialkylalanes and -gallanes R‘3M in 1:2 stoichiometry yield eight bisadducts of the type [Sb2R4][MR‘3]2 (R = Me, R‘ = t-Bu, M = Al 1, Ga 2; R = Et, M = Al, R‘ = Me 3, Et 4, t-Bu 5; M = Ga, R‘ = Me 6, Et 7, t-Bu 8), which were characterized by multinuclear NMR studies and elemental analysis. In addition, 1, 2, 5, and 8 are the first structurally characterized neutral main group Lewis acid−distibane bisadducts. 1−8 are unstable in solution toward the formation of heterocycles of the type [R2SbMR‘2]x. [Me2SbGa(t-Bu)2]3 (9) and [Et2SbGa(t-Bu)2]2 (10) have been isolated and their solid state structures determined by single-crystal X-ray diffrac…
Age and spatial structure of natural Pinus sylvestris stands in Latvia
2005
Abstract The age and spatial structure of six natural old growth Pinus sylvestris stands in Latvia were investigated, to attempt to identify retrospectively the past features of development. In each stand, one or two plots of size 200–900 m2 were established. Tree locations were mapped, stem diameter was measured, and tree age was determined from cores or by counting branch whorls. Tree distribution was assessed by Ripley's K function. A clumped spatial pattern was shown for P. sylvestris younger than 100 years. The temporal patterns of establishment could be partly linked to favourable climatic periods. The major disturbance affecting pine stands along the coast was windblown sand, which p…
Effect of humidity on the hysteresis of single walled carbon nanotube field-effect transistors
2008
Single walled carbon nanotube field-effedt transistores (SWCNT FETs) are attributed as possible building blocks for future molecular electronics. But often these transistors seem to randomly display hysteresis in their transfer characteristics. One reason for this is suggested to be water molecules adsorbed to the surface of the gate dielectric in this study we investigate the thysteresis of SWCNT FETs at different relative humidities. We find that SWCNT FETs having atomic layer deposited (ALD) Hf0 2 -Ti0 2 .- Hf0 2 as a gate dielectric retain their. ambient condition hysteresis better in dry N2 environment than the more commonly used SiO 2 gate oxide.
Synthesis of hyperbranched poly(tert-butyl acrylate) by self-condensing atom transfer radical polymerization of a macroinimer
2000
Using 2-hydroxyethyl α-bromoisobuty-rate as initiator, atom transfer radical polymerization (ATRP) of tert-butyl acrylate leads to poly(tert-butyl acrylate) (PtBA) with a hydroxyl group at one and a bromine atom at the other end. Esterification of the hydroxyl group of these heterotelechelic polymers with acryloyl chloride yields PtBA (M n = 3060) with a polymerizable double bond at one end and a bromine atom at the other end which can act as an initiator in ATRP (macroinimer). Self-condensing ATRP of such a macroinimer leads to hyperbranched or highly branched PtBA. The polymer was characterized by GPC viscosity measurements. Even at M w = 78800, a rather low polydispersity index of M w M …
Adaptative biochemical pathways and regulatory networks in Klebsiella oxytoca BAS-10 producing a biotechnologically relevant exopolysaccharide during…
2012
Abstract Background A bacterial strain previously isolated from pyrite mine drainage and named BAS-10 was tentatively identified as Klebsiella oxytoca. Unlikely other enterobacteria, BAS-10 is able to grow on Fe(III)-citrate as sole carbon and energy source, yielding acetic acid and CO2 coupled with Fe(III) reduction to Fe(II) and showing unusual physiological characteristics. In fact, under this growth condition, BAS-10 produces an exopolysaccharide (EPS) having a high rhamnose content and metal-binding properties, whose biotechnological applications were proven as very relevant. Results Further phylogenetic analysis, based on 16S rDNA sequence, definitively confirmed that BAS-10 belongs t…
Problematic internet use prior to and during the COVID-19 pandemic
2021
The health and socio-economic challenges arising from the COVID-19 pandemic have led to greater reliance on the internet to meet basic needs and responsibilities. Greater engagement in online activities may have negative mental and physical health consequences for some vulnerable individuals, particularly under mandatory self-isolation or ‘lockdown’ conditions. The present study investigated whether changes in levels of involvement in online activities during the COVID-19 pandemic (i.e., watching TV series,online sexual activities, video games, social networks, gambling, online shopping, and instant messaging) were associated with problematic internet use, as well as whether certain psychol…
Revising midlatitude summer temperatures back to A.D. 600 based on a wood density network
2015
Annually resolved and millennium-long reconstructions of large-scale temperature variability are primarily composed of tree ring width (TRW) chronologies. Changes in ring width, however, have recently been shown to bias the ratio between low- and high-frequency signals. To overcome limitations in capturing the full spectrum of past temperature variability, we present a network of 15 maximum latewood density (MXD) chronologies distributed across the Northern Hemisphere extratropics. Independent subsets of continental-scale records consistently reveal high MXD before 1580 and after 1910, with below average values between these periods. Reconstructed extratropical summer temperatures reflect n…