Search results for "A2"

showing 10 items of 1101 documents

Effects of particle clustering on the plastic deformation and damage initiation of particulate reinforced composite utilizing X-ray CT data and finit…

2018

In this paper, a new simulation technique which can include microstructural inhomogeneity of particulate reinforced composites is proposed to accurately study deformation pattern and damage mechanism in these composites. Three dimensional microstructures constructed from XCT images incorporated into finite element modeling codes with minimal approximation to capture the effects of cluster size, local volume fraction of particles in the cluster and the distance between clusters as relevant statistical quantities describing the microstructural inhomogeneity of particulate reinforced composites. A quantitative parameter as degree of clustering is defined to consider particle clustering effect.…

Yield (engineering)Materials scienceNon-destructive testing02 engineering and technologyFlow stressPlasticity01 natural sciencesIndustrial and Manufacturing Engineering0103 physical sciencesCluster (physics)von Mises yield criterionsimulointiComposite materialCluster analysista216Plastic deformationkomposiitit010302 applied physicsta114Mechanical EngineeringFinite element analysis (FEA)021001 nanoscience & nanotechnologymikrorakenteetParticle-reinforcementMechanics of MaterialsVolume fractionCeramics and CompositesDeformation (engineering)0210 nano-technologyCOMPOSITES PART B: ENGINEERING
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Zvaigžņotā Debess: 2007, Rudens

2007

Latvijas Zinātnes padome, Latvijas Universitāte

Zvaigžņotā debess 2007.gada rudenīOlimpiskais Saules aptumsumsOtrā Starptautiskā astronomijas un astrofizikas olimpiāde (2nd IOAA) IndonēzijāLatvijas 32.atklātā fizikas olimpiādeKrustvārdu mīklaMarsa melnie caurumiSAG2009 tīmekļa vietne www.astronomija2009.lvStarptautiskā Ģeofizikas gada (1957) atcereIn memoriam Bruno Biedriņš (1943-2007)Polārzvaigzne Polaris Aa un AbESA/NASA „Ulysses” misija – Saules-Zemes kosmiskā „kopdziesma”Kosmiskās telpas pētniecība – tuvākās nākotnes perspektīvasLatviešu astronoms Staņislavs Vasiļevskis (1907-1988) – dzīve un zinātniskais mantojumsKosmosa kuģis „SpaceShipOne” – suborbitāli kosmiskie lidojumiKosmiskā vīzija 2015-2025Pārnovas un planēta ZemeEiropas astronomijas nākotnes vīzijas ASTRONETČehu astronomijas amatieris Kamils Hornohs ASP balvaVissavienības Astronomijas un ģeodēzijas biedrības Rīgas nodaļaPiena Ceļa jaunie pavadoņiESA un NASA vienošanās – Džeimsa Veba kosmiskais teleskops JWST un lāzerinterferometra kosmiskā antena LISA PathfinderKosmiskā aparāta „Dawn” misija – pundurplanētas Vesta un CerēraKosmiskie laikapstākļiJapānas zonde „Hayabusa” pirmie rezultātiJubilārs Dzintars BlūmsLatvijas 34.atklātās matemātikas olimpiāde – uzdevumiFizikas docents Alfons Apinis (1911-1994)Igauņu astrofiziķis Aksels Kipers (1907-1984)
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The study of calcium signaling in lipid gustatory cells in mice

2012

The lipid-binding glycoprotein CD36, expressed by circumvallate papillae (CVP) of the mouse tongue, has been shown to be implicated in oro-gustatory perception of dietary lipids. We demonstrate that linoleic acid (LA) by activating sPLA2, cPLA2 and iPLA2 via CD36, produced arachidonic acid (AA) and lyso-phosphatidylcholine (Lyso-PC) which triggered Ca2+ influx in CD36-positive taste bud cells (TBC), purified from mouse CVP. LA induced the production of Ca2+ influx factor (CIF). CIF, AA and Lyso-PC exerted different actions on the opening of store-operated Ca2+ (SOC) channels, constituted of Orai proteins and regulated by STIM1, a sensor of Ca2+ depletion in the endoplasmic reticulum. We use…

[SDV.SA]Life Sciences [q-bio]/Agricultural sciencesLinoleic acidPLA2[SDV.SA] Life Sciences [q-bio]/Agricultural sciencesStim1Préférence gustative lipidiqueSOCAcide linoléiqueCD36[ SDV.SA ] Life Sciences [q-bio]/Agricultural sciencesOro-gustatory lipid preferenceOrai1/3
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Mesure de l’efficacité de la lutte contre l’ambroisie : étude de faisabilité

2013

Common ragweed (Ambrosia artemisiifolia L.) is known for its high allergenic pollens and by the difficulty to control this invasive plant which make it a problem for public health and is a harmfulness in rural areas. This first work aims to make a feasibility study to verify the proper functioning of selected traps and the correct implementation of specific procedures. It was decided to use passive traps SIGMA2 (SIGMA2 Like Trap ou SLT). Two geographical areas were selected, each with 4 traps: an infested area in Isère and a slightly infested area in Côte d'Or. SLT traps used can well collect pollen from local areas, the collected quantities vary in a corresponding manner according to the d…

[SDV] Life Sciences [q-bio][SDE] Environmental Sciences[SDV]Life Sciences [q-bio][SDE]Environmental SciencesSigma2pollenscapteur passif[SDV.BV]Life Sciences [q-bio]/Vegetal Biology[SDV.BV] Life Sciences [q-bio]/Vegetal BiologyallergieAmbroisie
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Ab-Initio Calculations of Oxygen Vacancy in Ga2O3 Crystals

2021

The research has been funded by the Science Committee of the Ministry of Education and Science of the Republic of Kazakhstan (Grant No. AP08856540). J. Purans and A.I.Popov acknowledge the ERAF project 1.1.1.1/20/A/057 “Functional Ultrawide Bandgap Gallium Oxide and Zinc Gallate Thin Films and Novel Deposition Technologies”. The Institute of Solid State Physics, University of Latvia (Latvia) as the Centre of Excellence has received funding from the European Union’s Horizon 2020 Framework Programme H2020-WIDESPREAD01-2016-2017-Teaming Phase2 under grant agreement No. 739508, project CAMART2.

ab-initio calculationsβ-ga2o3band structureQC1-999β-GaOGeneral Physics and Astronomy02 engineering and technologyDFT01 natural sciences7. Clean energyZinc gallateGallium oxideAb initio quantum chemistry methodsPolitical science0103 physical sciences:NATURAL SCIENCES:Physics [Research Subject Categories]media_common.cataloged_instanceEuropean unionmedia_common010302 applied physicsPhysicsGeneral Engineeringoxygen vacancydft021001 nanoscience & nanotechnologyEngineering physicsOxygen vacancy3. Good healthChristian ministry0210 nano-technologyLatvian Journal of Physics and Technical Sciences
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Fluidity and cytosolic Ca2+ concentration of circulating polymorphonuclear leukocytes at baseline in some chronic and acute clinical conditions: revi…

2016

Abstract. Objective: In this mini-review we describe the behavior of polymorphonuclear leukocyte (PMN) membrane fluidity and of PMN cytosolic Ca2+ concentration in some chronic and acute clinical conditions. Methods: PMN membrane fluidity was evaluated employing the fluorescent probe Fura-2AM, and PMN cytosolic Ca2+ concentration was evaluated using the fluorescent probe TMA-DPH. Results: From the determination of these two parameters investigated on resting PMNs, an almost constant increase in PMN cytosolic Ca2+ concentration in chronic clinical conditions, such as vascular atherosclerotic disease with and without diabetes mellitus, essential hypertension, chronic kidney disease, and diabe…

acute ischemic strokemedicine.medical_specialtyClinical BiochemistryCell calciumEssential hypertensionBiochemistryInorganic ChemistryCell calcium; membrane fluidity; fluorescence spectroscopy; polymorphonuclear leukocyte; vascular atherosclerotic disease; diabetes mellitus; chronic kidney disease; essential hypertension; myocardial infarction; acute ischemic strokevascular atherosclerotic diseaseDiabetes mellitusInternal medicineCa2 concentrationmedicineMembrane fluidityMyocardial infarctionAcute ischemic strokePolymorphonuclear leukocytediabetes mellitubusiness.industrymembrane fluiditypolymorphonuclear leukocyteessential hypertensionfluorescence spectroscopymedicine.diseaseCytosolmyocardial infarctionCardiologybusinesschronic kidney disease
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Searching for a robust strategy for minimizing alkali chlorides in fluidized bed boilers during burning of high SRF-energy-share fuel

2015

Abstract To meet the increasing volume of waste to be treated via energy recovery, high SRF-energy-share fuel is being fired in conventional waste-to-energy facilities. In this work, corrosion related risk during firing of 70 e-% share (target fuel) is studied and compared against the base case fuel containing 50 e-% share. Cl and S concentration is highest in the target fuel as a direct result of increasing the proportion of SRF in the fuel mixture. Br, Zn and Pb showed the same trend. Meanwhile, the concentration of Na, K, Al and Si are highly dependent on the type of the SRF fired. The corrosion risk of the base and target fuels are analyzed using the composition of the fine aerosol frac…

alkali chloride mitigationEnergy recoveryFlue gascorrosionWaste-to-energyWaste managementGeneral Chemical EngineeringOrganic ChemistryEnergy Engineering and Power TechnologyAerosolCorrosionCorrosionWaste-to-energychemistry.chemical_compoundFuel Technologychemistrywaste-to-energyFluidized bedSRFAlkali chloride mitigationSulfateta215SuperheaterFuel
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Echovirus 1 infektion vaikutus epidermaalisen kasvutekijäreseptorin endosytoosiin ja signalointiin

2013

Epidermaalinen kasvutekijäreseptori (EGFR) on yhdessä kollageeni- ja lamiinireseptori α2β1-integriinin kanssa tärkeä tekijä solun selviytymisen, kiinnittymisen ja jakautumisen säätelemisessä sekä syöpäsoluissa. Kasvutekijän sitoutumisen jälkeen EGFR:t dimerisoituvat, endosytoituvat klatriinivälitteisen endosytoosin kautta ja kulkeutuvat solun sisällä kolmen eri reitin mukaisesti: 1) EGFR-ligandi-kompleksi voi ubikitinaation seurauksena päätyä lysosomaaliseen pH:sta riippuvaan hajoitukseen, EGFR kierrättyy takaisin solukalvolle 2) ligandin irtoamisen tai 3) UBPY de-ubikitinaatioenstyymin toimesta. α2β1-integriinireseptori klusteroituu solukalvolle kiinnityttyään kollageeniin, lamiiniin, Echo…

alpha2beta1-IntegriiniEndosomaalinen kuljetusEpidermaalinen kasvutekijäreseptoriECHO-viruksetEchovirus 1endosytoosiProteiinikinaasi C
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Alkaline pretreatment to enhance one-stage CH4 and two-stage H2/CH4 production from sunflower stalks: Mass, energy and economical balances

2015

Abstract Biological production of second generation biofuels such as biohydrogen (H2) or methane (CH4) represents a promising alternative to fossils fuels. Alkaline pretreatments of lignocellulosic biomass are known to enhance the accessibility and the bioconversion of hollocelluloses during anaerobic digestion and dark fermentation processes. In the present study, four different configurations were investigated: one-stage CH4 continuous and two-stage H2 batch/CH4 continuous process with and without alkaline pretreatment of sunflower stalks (55 °C, 24 h, 4 g NaOH/100 g TS). The results showed that two stage H2/CH4 (150 ± 3.5 mL CH4 g−1 VS) did not improve methane yields compared to one stag…

anaerobic digestionWaste managementChemistryBioconversionGeneral Chemical Engineeringmethane[SDV]Life Sciences [q-bio]biohydrogenBiomassLignocellulosic biomassGeneral ChemistryDark fermentationPulp and paper industry7. Clean energyIndustrial and Manufacturing EngineeringAnaerobic digestiondark fermentation13. Climate actionBiofuelDigestateEnvironmental ChemistryBiohydrogenta219lignocellulosic biomassenergy assessment
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Efficiency of acetic acid and formic acid as a catalyst in catalytical and mechanocatalytical pretreatment of barley straw

2016

Abstract In this study, the potential of organic acids (formic acid, acetic acid) in a catalytical and mechanocatalytic conversion of lignocellulosic barley straw to valuable sugars is explored using sulfuric acid as a reference. Acid-catalyzed hydrolysis has been carried out with acid-impregnated samples as well as unmodified barley straw. In the mechanocatalytical approach, pretreatment consists of impregnation with the acid catalyst and mechanical treatment by ball milling following chemical hydrolysis. Straw samples and residues were analyzed by Fourier transform infrared spectrometry (FT-IR) whereas hydrolysate analysis was based on total reducing sugar (TRS) determination following th…

animal structuresformic acidFormic acidta220010402 general chemistry01 natural sciencesHydrolysateCatalysischemistry.chemical_compoundAcetic acidHydrolysislignocelluloseOrganic chemistryWaste Management and Disposalta215chemistry.chemical_classification010405 organic chemistryRenewable Energy Sustainability and the Environmentmechanocatalytical conversionfood and beveragesForestrySulfuric acidStraw0104 chemical sciencesReducing sugaracetic acidchemistryBarley strawAgronomy and Crop ScienceNuclear chemistryBiomass and Bioenergy
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