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Five chiral, racemic dialkyl α-hydroxyethylphosphonates and α-hydroxyethyl-diarylphosphine oxides were prepared in a scalable manner. Possibilities for the optical resolution of the racemic hydroxyphosphine oxides were explored via diastereomeric complex-forming experiments. The acidic calcium salt of O,O′-dibenzoyl-(2R,3R)-tartaric acid and O,O′-di-p-tolyl-(2R,3R)-tartaric acid were chosen as the resolving agents. The role of the solvent in the enantiomeric discrimination was investigated. The diastereomeric complex could be obtained in a crystalline form for α-hydroxyethyl-diphenylphosphine oxide and α-hydroxyethyl-bis(4-methylphenyl)phosphine oxide. However, in the third case, for α-hydroxyethyl-bis(3,5-dimethylphenyl)phosphine oxide, there was no chiral discrimination. Decomposition of the recrystallized diastereomeric complex followed by decomposition of the complex yielded the target compounds in 77/90% enantiomeric excess. The absolute configuration of the hydroxyethyl-diphenylphosphine oxide was determined by single-crystal X-ray diffraction measurements. The interactions stabilizing the supramolecular associate were evaluated. [ABSTRACT FROM AUTHOR]

Climate change has several effects, including the changes of water discharge values and flood occurrences. In the present study five catchments are analysed using the European hydrology and climate data explorer. Two hydrological models and eight regional climate model simulations with three different representative concentration pathway (RCP) scenarios were selected for the investigation, focusing on the period 2071–2100 relative to 1971–2000. The catchments are located in different climate zones in Europe, therefore, it is possible to compare how climate and its changes determine mean and maximum water discharge. In addition, there is a special focus on the 10- and 50-year recurrence of floods. [ABSTRACT FROM AUTHOR]

When pre-treated with social stimuli prior to testing, dogs are more susceptible to human influence in a food preference task. This means, after a positive social interaction they are more willing to choose the smaller amount of food indicated by the human, as opposed to their baseline preference for the bigger amount. In the current study we investigate if and how various forms of social interaction modulate choices in the same social susceptibility task, testing dogs with varying early life history (pet dogs, therapy dogs, former shelter dogs). In line with previous studies, dogs in general were found to be susceptible to human influence as reflected in the reduced number of "bigger" choices in the human influence, compared to baseline, trials. This was true not only for pet dogs with a normal life history, but also for dogs adopted from a shelter. Therapy dogs, however, did not uniformly change their preference for the bigger quantity of food in the human influence trials; they only did so if prior to testing they had been pre-treated with social stimuli by their owner (but not by a stranger). Pet dogs were also more influenced after pre-treatment with social stimuli by their owner compared to ignoring and separation; however after pre-treatment by a stranger their behaviour did not differ from ignoring and separation. Former shelter dogs on the other hand were equally influenced regardless of pre-treatment by owner versus stranger. In summary these results show that dogs' social susceptibility is modulated by both interactions immediately preceding the test as well as by long term social experiences. [ABSTRACT FROM AUTHOR]

Precipitation is the major atmospheric source of surface water, thus, in order to build appropriate adaptation strategies for various economic sections related to water resources it is essential to provide projections for precipitation tendencies as exact as possible. Extreme precipitation events are especially important from this point of view since they may result in different environmental, economical, and/or even human health damages. Excessive precipitation for instance may induce floods, flash-floods, landslides, traffic accidents. On the other hand, lack of precipitation is not favorable either: long dry periods affect agricultural production quite negatively, and hence, food safety can be threatened. Several precipitation-related indices (i.e., describing drought or intensity, exceeding different percentile-based or absolute threshold values) are analyzed for the Carpathian region for 1961–2100. For this purpose 11 completed regional climate model simulations are used from the ENSEMBLES database. Before the thorough analysis, a percentile-based bias correction method was applied to the raw data, for which the homogenized daily gridded CarpatClim database (1961–2010) served as a reference. Absolute and relative seasonal mean changes of climate indices are calculated for two future time periods (2021–2050 and 2071–2100) and for three subregions within the entire Carpathian region, namely, for Slovakia, Hungary and Romania. According to our results, longer dry periods are estimated for the summer season, mainly in the southern parts of the domain, while precipitation intensity is likely to increase. Heavy precipitation days and high percentile values are projected to increase, especially, in winter and autumn.