Search results for "TEMPERATURE"
showing 10 items of 3798 documents
Photoinduced changes in phytochromes studied by means of low temperature UV-Vis spectroscopy
2018
Phytochromes are a major family of red-light-sensing kinases that control diverse cellular functions in plants, bacteria and fungi. These proteins must relay structural signals from the sensory site over large distances to regulatory output domains. To accomplish this function, they undergo rather large structural changes from one state to another. The general aim of this work was to study these structural changes and possible protonation states of the photosensory core of the bacteriophytochrome from Deinococcus radiodurans in the intermediate states of the photoreaction, which became possible to observe under low temperatures. Moreover, it was interesting to investigate the role Serine272…
Heat-sensitive UV-Vis measurements for Phytochrome
2016
Fytokromit ovat punaista valoa aistivia proteiineja, jotka säätelevät suurta joukkoa solun toimintoja kasvi-, bakteeri- ja sienisoluissa. Nämä valoaktiiviset proteiinit muuntavat konformaatiotaan palautuvasti aktiivisen (Pfr) ja inaktiivisen (Pr) tilan välillä. Fytokromien aminohappojen väliset heikot vuorovaikutukset - etenkin vetysidokset - vaikuttavat lopulta laskostumiseen ja proteiinin lämpöstabiiliuteen. Fytokromit esiintyvät homodimeerisinä rakenteina, joiden monomeerit koostuvat useista domeeneista. Nämä jakautuvat N- terminaaliseen valosensitiiviseen moduuliin (PSM) ja C-terminaaliseen OutPut moduliin (OPM). PSM koostuu kolmesta domeenista (PAS-GAF ja PHY). Tässä työssä tutkittiin …
Polypropylene/polyhedral oligomeric silsesquioxane nanocomposites – study of free volumes, crystallinity degree and mass flow rate
2016
Nanokompozyty polipropylen/poliedryczne oligomeryczne silseskwioksany (PP/POSS) przygotowano metodą mieszania w stanie stopionym polimeru. Wpływ struktury oraz ilości zastosowanych nanonapełniaczy POSS na objętości swobodne w polipropylenie określono z zastosowaniem spektroskopii czasów życia pozytonów (PALS). Ustalono zależności pomiędzy parametrami PALS: czasem życia o-Ps (τ3) i natężeniem (I3) składowej o-Ps oraz wartościami stopnia krystaliczności (Xc ) i masowego wskaźnika szybkości płynięcia (MFR) badanych materiałów. Obecność nanonapełniaczy POSS wpłynęła na liczbę i rozmiary objętości swobodnych w polimerze, co spowodowało zmianę mikrostruktury osnowy polipropylenowej. Wraz ze zwięk…
Impact of Separator Thickness on Temperature Distribution in Single Cell of Polymer Electrolyte Fuel Cell Operated at Higher Temperature of 90 °C and…
2022
The New Energy and Industry Technology Development Organization (NEDO) road map (Japan, 2017) has proposed that a polymer electrolyte fuel cell (PEFC) system, which operates at a temperature of 90 °C and 100 °C, be applied for stationary and mobility usage, respectively. This study suggests using a thin polymer electrolyte membrane (PEM) and a thin gas diffusion layer (GDL), at the same time, to achieve better power-generation performance, at a higher temperature than usual. The focus of this paper is to clarify the effect of separator thickness on the distribution of temperature at the reaction surface (Treact), with the relative humidity (RH) of the supply gasses and initial operation tem…
Effects of pyrolysis temperature on the hydrologically relevant porosity of willow biochar
2018
Biochar pore space consists of porosity of multiple length scales. In direct water holding applications like water storage for plant water uptake, the main interest is in micrometre-range porosity since these pores are able to store water that is easily available for plants. Gas adsorption measurements which are commonly used to characterize the physical pore structure of biochars are not able to quantify this pore-size range. While pyrogenetic porosity (i.e. pores formed during pyrolysis process) tends to increase with elevated process temperature, it is uncertain whether this change affects the pore space capable to store plant available water. In this study, we characterized biochar poro…
Partial Discharges in HVDC Cables - The Effect of the Temperature Gradient During Load Transients
2021
The paper investigates the role of the space charge accumulation phenomena in the inception of Partial Discharges (PD) in a defect within the bulk of the dielectrics of a High Voltage Direct Current (HVDC) cable. It is widespread accepted that the number of PD occurring in an HVDC cable during its lifetime is largely less than that under AC voltage stress. This is essentially due to higher values of the voltage between the conductor and the screen needed to trigger PD under a steady DC voltage than the same value under AC stress. Nevertheless, due to the dependency of the electrical conductivity of the insulation on the electric field and temperature, PD in HVDC cables is strongly influence…
Using the hierarchical modeling approach to derive spatial distribution of precipitation and temperature datasets. A case study for the area of Sicil…
2013
The interest for spatial interpolating climatic variables available by means of point measurements, as precipitation and temperature, arises from different needs, ranging from their usage for hydrological models to the reconstruction of climatic atlas of spatially distributed data. In some areas the spatial distribution of these variables can be related to the extremely variable morphology of the area. While simple deterministic interpolation methods usually produce just the spatial distribution of the variable of interest, implicitly relying on the spatial autocorrelation and manually tuning a few parameters, more complex statistical models, are able to derive the uncertainty associated wi…
A Statistical Approach for A-Posteriori Deployment of Microclimate Sensors in Museums: A Case Study
2022
[EN] The deployment of sensors is the first issue encountered when microclimate monitoring is planned in spaces devoted to the conservation of artworks. Sometimes, the first decision regarding the position of sensors may not be suitable for characterising the microclimate close to climate sensitive artworks or should be revised in light of new circumstances. This paper fits into this context by proposing a rational approach for a posteriori deployment of microclimate sensors in museums where long-term temperature and relative humidity observations were available (here, the Rosenborg Castle, Copenhagen, Denmark). Different statistical tools such as box-and-whisker plots, principal component …
The effect of a temperature-sensitive prophage on the evolution of virulence in an opportunistic bacterial pathogen.
2022
https://doi.org/10.1111/mec.16638 Abstract Viruses are key actors of ecosystems and have major impacts on global biogeochemical cycles. Prophages deserve particular attention as they are ubiquitous in bacterial genomes and can enter a lytic cycle when triggered by environmental conditions. We explored how temperature affects the interactions between prophages and other biological levels by using an opportunistic pathogen, the bacterium Serratia marcescens, that harbours several prophages and that had undergone an evolution experiment under several temperature regimes. We found that the release of one of the prophages was temperature-sensitive and malleable to evolutionary changes. We furthe…
Purification and partial characterization of aminopeptidase from barley (Hordeum vulgare L.) seeds.
2013
Aminopeptidases (EC 3.4.11) are proteolytic enzymes, which hydrolyze one amino acid from N-terminus of peptidic substrates. Inhibitors of plant aminopeptidases can find an application in agriculture as herbicides. Isolation and partial characterization of aminopeptidase from barley (Hordeum vulgare L.) seeds has been described. The enzyme was purified to molecular homogeneity using a six-step purification procedure (precipitation with (NH4)2SO4, followed by chromatography on Sephadex G-25, DEAE-Sepharose, Sephacryl HR 300, Macro-Prep Q and Phenyl-Sepharose HP columns). The enzyme was purified 365-fold with recovery above 18%. The molecular weight of the purified enzyme was determined by SDS…