Search results for "DST"
showing 10 items of 178 documents
Determination of impurity distributions in ingots of solar grade silicon by neutron activation analysis
2017
AbstractIn a series of crystallization experiments, the directional solidification of silicon was investigated as a low cost path for the production of silicon wafers for solar cells. Instrumental neutron activation analysis was employed to measure the influence of different crystallization parameters on the distribution of 3d-metal impurities of the produced ingots. A theoretical model describing the involved diffusion and segregation processes during the solidification and cooling of the ingots could be verified by the experimental results. By successive etching of the samples after the irradiation, it could be shown that a layer of at least 60 μm of the samples has to be removed to get r…
Forecasting the volatility of biofuel feedstock prices: the US evidence
2019
Given that, nowadays, 40% of the US corn crop is used for biofuel production, there is a growing concern that the rise in biofuel production might lead to an increase in food prices. However, it is also obvious that significant growth in biofuel use has minimized the demand for fossil fuel and has hence reduced the volume of carbon emissions. It is therefore crucial to model corn market volatility precisely because such an estimate could play a vital role in stabilizing food and biofuel market prices. For this purpose, we consider using the information content of the corn implied volatility (CIV) index to predict the corn futures market return volatility. Using symmetric and asymmetric GARC…
European Union legislation on macroalgae products
2021
AbstractMacroalgae-based products are increasing in demand also in Europe. In the European Union, each category of macroalgae-based products is regulated separately. We discuss EU legislation, including the law on medicinal products, foods including food supplements and food additives, feed and feed additives, cosmetics, packaging materials, fertilizers and biostimulants, as well as biofuels. Product safety and consumer protection are the priorities with any new products. Macroalgae products can be sold as traditional herbal medicines. The novel food regulation applies to macroalgae foods that have not previously been used as food, and organic macroalgae are a specific regulatory category. …
Localization microscopy of DNA in situ using Vybrant(®) DyeCycle™ Violet fluorescent probe: A new approach to study nuclear nanostructure at single m…
2016
Higher order chromatin structure is not only required to compact and spatially arrange long chromatids within a nucleus, but have also important functional roles, including control of gene expression and DNA processing. However, studies of chromatin nanostructures cannot be performed using conventional widefield and confocal microscopy because of the limited optical resolution. Various methods of superresolution microscopy have been described to overcome this difficulty, like structured illumination and single molecule localization microscopy. We report here that the standard DNA dye Vybrant(®) DyeCycle™ Violet can be used to provide single molecule localization microscopy (SMLM) images of …
Candida blood stream infections observed between 2011 and 2016 in a large Italian University Hospital: A time-based retrospective analysis on epidemi…
2019
Candida bloodstream infection (BSI) represents a growing infective problem frequently associated to biofilm production due to the utilization of intravascular devices. Candida species distribution (n = 612 strains), their biofilm production and hospital antifungal drug consumption were evaluated in different wards of a tertiary care academic hospital in Italy during the years 2011–2016. In the considered time window, an increasing number of Candida BSI (p = 0.005) and of biofilm producing strains were observed (p<0.0001). Although C. albicans was the species more frequently isolated in BSI with a major biofilm production, an increased involvement of non-albicans species was reported, partic…
Quantitative super-resolution localization microscopy of DNA in situ using Vybrant® DyeCycle™ Violet fluorescent probe.
2016
Single Molecule Localization Microscopy (SMLM) is a recently emerged optical imaging method that was shown to achieve a resolution in the order of tens of nanometers in intact cells. Novel high resolution imaging methods might be crucial for understanding of how the chromatin, a complex of DNA and proteins, is arranged in the eukaryotic cell nucleus. Such an approach utilizing switching of a fluorescent, DNA-binding dye Vybrant® DyeCycle™ Violet has been previously demonstrated by us (Żurek-Biesiada et al., 2015) [1]. Here we provide quantitative information on the influence of the chemical environment on the behavior of the dye, discuss the variability in the DNA-associated signal density,…
A role for TASK2 channels in the human immunological synapse.
2020
The immunological synapse is a transient junction that occurs when the plasma membrane of a T cell comes in close contact with an APC after recognizing a peptide from the antigen-MHC. The interaction starts when CRAC channels embedded in the T cell membrane open, flowing calcium ions into the cell. To counterbalance the ion influx and subsequent depolarization, Kv 1.3 and KCa3.1 channels are recruited to the immunological synapse, increasing the extracellular K+ concentration. These processes are crucial as they initiate gene expression that drives T cell activation and proliferation. The T cell-specific function of the K2P channel family member TASK2 channels and their role in autoimmune p…
Is prolonged infusion of piperacillin/tazobactam and meropenem in critically ill patients associated with improved pharmacokinetic/pharmacodynamic an…
2016
Objectives: We utilized the database of the Defining Antibiotic Levels in Intensive care unit patients (DALI) study to statistically compare the pharmacokinetic/pharmacodynamic and clinical outcomes between prolonged- infusion and intermittent-bolus dosing of piperacillin/tazobactam and meropenem in critically ill patients using inclusion criteria similar to those used in previous prospective studies. Methods: This was a post hoc analysis of a prospective, multicentre pharmacokinetic point-prevalence study (DALI), which recruited a large cohort of critically ill patients from 68 ICUs across 10 countries. Results: Of the 211 patients receiving piperacillin/tazobactam and meropenem in the DAL…
Staphylococcus aureus bloodstream infection in patients with prosthetic joint included in the prospective VIRSTA cohort study: frequency and time of …
2019
International audience; Among 143 patients of the VIRSTA cohort study with Staphylococcus aureus bacteremia and an arthroplasty implanted for more than a year, S. aureus periprosthetic joint infection was observed in 19%. Signs of infection (pain and swelling) were always present, in median 1 day (range, 0-21 days) after onset of bacteremia. Staphylococcus aureus has both a high potential for metastatic infection and a high affinity for foreign material. Possible prosthesis infection is of clinical concern in all patients with preexisting prosthetic materials experiencing S. aureus bloodstream infection (SAB). Prosthetic joints are especially prone to infection during the course of bacterem…
Lokanu oglekļa nanocaurulīšu-metālu halkogenīdu hibrīdstruktūru sintēze un īpašības
2021
Darbā ir veikti pētījumi par lokanu oglekļa nanocaurulīšu tīklojumu, oglekļa nanocaurulīšu-metālu halkogenīdu hibrīdstruktūru un to nanokompozītu ar nevadošiem polimēriem termoelektrisko īpašību izmaiņām materiālu lieces iespaidā. Bakalaura darba ietvaros tika sagatavoti lokani oglekļa nanocaurulīšu tīklu un oglekļa nanocaurulīšu-antimona telurīda/ oglekļa nanocaurulīšu-bismuta selenīda hibrīdstruktūru paraugi ar dažādu hibrīdstruktūru sadalījumu parauga tilpumā, kā arī tie tika iemaisīti vai iekapsulēti nevadoša polimēra matricā. Tika pētīta šo paraugu termoelektrisko īpašību (pretestības un Zēbeka koeficienta) atkarība no to liekuma rādiusa, un analizēti iegūtie rezultāti. Šāda tipa parau…