17 research outputs found
Air temperature conditions in northern Nordaustlandet (NE Svalbard) at the end of World War II
This article presents the results of an investigation into air temperature conditions in northern Nordaustlandet (NE Svalbard) based on meteorological observations made by German soldiers towards the end of World War II (1944/1945) and 4 months after its end. Traditional analysis using mean monthly data was supplemented by a detailed analysis based on daily data: maximum temperature, minimum temperature and diurnal temperature range. The latter kind of data made it possible to study such aspects of climate as the number of “characteristic days”
(i.e., the number of days with temperatures exceeding specified thresholds), dayto-day temperature variability, and duration, onset and end dates of thermal seasons. The results from Nordaustlandet for the warmest period of the early 20th century warming period (ETCWP) were compared with temperature conditions both historical (the end part of the Little Ice Age) and contemporary (different sub-periods taken from the years 1981–2017) to estimate the range of warming during the ETCWP.
Analysis reveals that the expedition year 1944/1945 in Nordaustlandet was, in the majority of months, the warmest of all analysed periods, that is, both historical and contemporary periods. The study period was markedly warmer than 1981–2010 (mean annual −6.5 vs. −8.4 °C) but colder than the periods 2011–2016 (−5.7 °C) and 2014–2017 (−5.8 °C). The majority of mean monthly air temperatures in the ETCWP lies within two standard deviations of the modern 2014–2017 mean. This means that values of air temperature in the study period lie
within the range of recent temperature variability. All other thermal characteristics show changes in accordance with expectations associated with general warming of the Arctic (i.e., a decrease in diurnal temperature range and number of cold days, and an increase in number of warm days). The latter days were most common in the ETCWP
Texture of recent morainic deposits of a terminal zone of the Werenskiöld Glacier (Spitsbergen)
Thermoluminescence and Scintillation Time Profiles of BaF:Ce
In this communication we present results of measurements of low temperature thermoluminescence, isothermal decays, steady state radioluminescence yield, and scintillation time profiles at various temperatures on two scintillator materials, BaF:Ce and undoped BaF. We find that all these results can be consistently interpreted in the frame of a model that includes several relatively shallow charge traps. We have identified and characterized one particular shallow trap that causes the decay of the dominant scintillation component of BaF:Ce to be slower than radiative, as well as a set of others that are responsible for even slower components in the scintillation time profile of this material
ADMET and Solubility Analysis of New 5-Nitroisatine-Based Inhibitors of CDK2 Enzymes
The development of new substances with the ability to interact with a biological target is only the first stage in the process of the creation of new drugs. The 5-nitroisatin derivatives considered in this study are new inhibitors of cyclin-dependent kinase 2 (CDK2) intended for anticancer therapy. The research, carried out based on the ADMET (absorption, distribution, metabolism, excretion, toxicity) methods, allowed a basic assessment of the physicochemical parameters of the tested drugs to be made. The collected data clearly showed the good oral absorption, membrane permeability, and bioavailability of the tested substances. The analysis of the metabolite activity and toxicity of the tested drugs did not show any critical hazards in terms of the toxicity of the tested substances. The substances’ low solubility in water meant that extended studies tested compounds were required, which helped to select solvents with a high dissolving capacity of the examined substances, such as DMSO or NMP. The use of aqueous binary mixtures based on these two solvents allowed a relatively high solubility with significantly reduced toxicity and environmental index compared to pure solvents to be maintained, which is important in the context of the search for green solvents for pharmaceutical use