Search results for "QD1-999"
showing 10 items of 1282 documents
Positron Annihilation Lifetime Spectroscopy Insight on Free Volume Conversion of Nanostructured MgAl2O4 Ceramics
2021
H.K. and A.I.P. are grateful for the support from the COST Action CA17126. H.K. was also supported by the Ministry of Education and Science of Ukraine (project for young researchers No. 0119U100435). In addition, I.K. and H.K. were also supported by the National Research Foundation of Ukraine via project 2020.02/0217, while the research of A.I.P. was funded by the Latvian research council via the Latvian National Research Program under the topic ?High-Energy Physics and Accelerator Technologies?, Agreement No: VPP-IZM-CERN-2020/1-0002. In addition, the research of A.I.P. has been supported by the Latvian-Ukrainian Grant LV-UA/2021/5. The Institute of Solid State Physics, University of Latvi…
9,10-Phenanthrenedione as Visible-Light Photoredox Catalyst: A Green Methodology for the Functionalization of 3,4-Dihydro-1,4-Benzoxazin-2- Ones thro…
2018
A visible-light photoredox functionalization of 3,4-dihydro-1,4-benzoxazin-2-ones through a Friedel-Crafts reaction with indoles using an inexpensive organophotoredox catalyst is described. The reaction uses a dual catalytic system that is formed by a photocatalyst simple and cheap, 9,10-phenanthrenedione, and a Lewis acid, Zn(OTf)2. 5W white LEDs are used as visible-light source and oxygen from air as a terminal oxidant, obtaining the corresponding products with good yields. The reaction can be extended to other electron-rich arenes. Our methodology represents one of the most valuable and sustainable approach for the functionalization of 3,4-dihydro-1,4-benzoxazin-2-ones, as compared to th…
A Regional Geography Approach to Understanding the Environmental Changes as a Consequence of the COVID-19 Lockdown in Highly Populated Spanish Cities
2021
Spain has been highly impacted by the COVID-19 pandemic, which is reflected at different scales. From an economic point of view, lockdowns and the reduction of activities have damaged the country (e.g., complete lockdown from March 13 to June 21, 2020). However, it is not clear if the associated environmental impacts could be observed in 2020. Currently, studies on the effects of the lockdown (e.g., decrease in economic activities, transport and social communication) on specific parameters related to climate change, such as air temperature or air pollution, due to a drastic decrease in human activities are rare. They are focused on specific cities and short periods of time. Therefore, the m…
First in-situ measurements of plume chemistry at mount garet volcano, island of gaua (Vanuatu)
2020
Recent volcanic gas compilations have urged the need to expand in-situ plume measurements to poorly studied, remote volcanic regions. Despite being recognized as one of the main volcanic epicenters on the planet, the Vanuatu arc remains poorly characterized for its subaerial emissions and their chemical imprints. Here, we report on the first plume chemistry data for Mount Garet, on the island of Gaua, one of the few persistent volatile emitters along the Vanuatu arc. Data were collected with a multi-component gas analyzer system (multi-GAS) during a field campaign in December 2018. The average volcanic gas chemistry is characterized by mean molar CO2/SO2, H2O/SO2, H2S/SO2 and H2/SO2 ratios …
Imidazolium Based Ionic Liquids: A Promising Green Solvent for Water Hyacinth Biomass Deconstruction.
2018
Water hyacinth (WH) is a troublesome aquatic weed of natural and artificial water bodies of India and other tropical countries and causing severe ecological problems. The WH biomass is low in lignin content and contains high amount of cellulose and hemicellulose, making it suitable material for conversion into liquid fuels for energy production. This study highlighted that, how different imidazolium based ionic liquids (ILs) [1-alkyl-3-methylimidazolium bromide, [Cnmim]Br (n = 2, 4, 6, 8, and 10)] with tunable properties can be employed for the degradation of WH biomass. Different characterizations techniques, such as XRD, FT-IR, SEM, and DSC are used to unravel the interplay between ILs an…
Characterization of the Copper Transporters from Lotus spp. and Their Involvement under Flooding Conditions
2019
Forage legumes are an important livestock nutritional resource, which includes essential metals, such as copper. Particularly, the high prevalence of hypocuprosis causes important economic losses to Argentinian cattle agrosystems. Copper deficiency in cattle is partially due to its low content in forage produced by natural grassland, and is exacerbated by flooding conditions. Previous results indicated that incorporation of Lotus spp. into natural grassland increases forage nutritional quality, including higher copper levels. However, the biological processes and molecular mechanisms involved in copper uptake by Lotus spp. remain poorly understood. Here, we identify four genes that encode p…
Phosphinotripeptidic Inhibitors of Leucylaminopeptidases
2021
Phosphinate pseudopeptide are analogs of peptides containing phosphinate moiety in a place of the amide bond. Due to this, the organophosphorus fragment resembles the tetrahedral transition state of the amide bond hydrolysis. Additionally, it is also capable of coordinating metal ions, for example, zinc or magnesium ions. These two properties of phosphinate pseudopeptides make them an ideal candidate for metal-related protease inhibitors. This research investigates the influence of additional residue in the P2 position on the inhibitory properties of phosphinopeptides. The synthetic strategy is proposed, based on retrosynthetic analysis. The N-C-P bond formation in the desired compounds is …
The Odorant-Binding Proteins of the Spider Mite Tetranychus urticae
2021
Spider mites are one of the major agricultural pests, feeding on a large variety of plants. As a contribution to understanding chemical communication in these arthropods, we have characterized a recently discovered class of odorant-binding proteins (OBPs) in Tetranychus urticae. As in other species of Chelicerata, the four OBPs of T. urticae contain six conserved cysteines paired in a pattern (C1–C6, C2–C3, C4–C5) differing from that of insect counterparts (C1–C3, C2–C5, C4–C6). Proteomic analysis uncovered a second family of OBPs, including twelve members that are likely to be unique to T. urticae. A three-dimensional model of TurtOBP1, built on the recent X-ray structure of Varroa destruc…
An Arabidopsis Mutant Over-Expressing Subtilase SBT4.13 Uncovers the Role of Oxidative Stress in the Inhibition of Growth by Intracellular Acidificat…
2020
Intracellular acid stress inhibits plant growth by unknown mechanisms and it occurs in acidic soils and as consequence of other stresses. In order to identify mechanisms of acid toxicity, we screened activation-tagging lines of Arabidopsis thaliana for tolerance to intracellular acidification induced by organic acids. A dominant mutant, sbt4.13-1D, was isolated twice and shown to over-express subtilase SBT4.13, a protease secreted into endoplasmic reticulum. Activity measurements and immuno-detection indicate that the mutant contains less plasma membrane H+-ATPase (PMA) than wild type, explaining the small size, electrical depolarization and decreased cytosolic pH of the mutant but not orga…
Synthesis of Isomaltooligosaccharides by Saccharomyces cerevisiae Cells Expressing Aspergillus niger α‑Glucosidase
2017
The α-glucosidase encoded by the aglA gene of Aspergillus niger is a secreted enzyme belonging to family 31 of glycoside hydrolases. This enzyme has a retaining mechanism of action and displays transglycosylating activity that makes it amenable to be used for the synthesis of isomaltooligosaccharides (IMOs). We have expressed the aglA gene in Saccharomyces cerevisiae under control of a galactose-inducible promoter. Recombinant yeast cells expressing the aglA gene produced extracellular α-glucosidase activity about half of which appeared cell bound whereas the other half was released into the culture medium. With maltose as the substrate, panose is the main transglycosylation product after 8…