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Trends in the influence of a proton-donor solvent on the reaction of aminolysis of ethylene carbonate, which proceeds through concerted and stepwise mechanisms, are studied. The study is based on kinetic data of model reactions in alcohol solutions and results of DFT quantum chemical calculations of reaction paths that involve hydrogen-bonded transition states and intermediates containing different numbers of solvent molecules in the proton-transfer and stabilization cycles. The calculated data on the activation energies of the reaction, which includes cycles of different sizes, indicate that the stepwise mechanism is preferable compared to the concerted one when the reaction proceeds in methanol. The activation barrier of the stepwise path of the reaction is lower by 2.9 kcal/mol than that for the concerted path. Only the proton-transfer cycle is essential for the progress of the reaction, and the presence of a stabilization cycle does not lead to a decrease in the activation barrier. [ABSTRACT FROM AUTHOR]

The mechanism of bifunctional catalysis by acetic acid in the addition reaction of amines with cyclocarbonates was studied by the DFT (PBE/TZ2P) method. Several one-step and multistep reaction pathways were found. The barrier for the transformation through the most favorable pathway in the presence of acetic acid was shown to substantially decrease (to ∼12 kcal mol) compared to the non-catalytic reaction (∼33 kcal mol) and the reaction involving the second amine molecule as the catalyst (∼22 kcal mol). The kinetics of the model reaction of ethylene carbonate with butylamine in dioxane was experimentally studied, and it was found that the effective activation energy decreases to 5.3 and 1.1 kcal mol for the channels involving one and two amine molecules, respectively, compared to the reaction in the absence of acetic acid (14.0 and 3.7 kcal mol). [ABSTRACT FROM AUTHOR]

Poly- and oligomerization of serial elements are among the ways to enhance, weaken or even change organ's function and might contribute to adaptation of animals. Involvement of thyroid hormones in development and formation of adult phenotype of scale cover was found recently. Cyprinid fish blue bream Ballerus ballerus has relatively high number of scales in lateral line (62-77) and may serve as appropriate object to examine the role of thyroid regulation of scale number in fish. Individuals kept under different hormonal conditions manifest highly differential number of scales. Experimental variation of scale number (49-114) broadly exceeds the limits of natural variation known for species. Goitrogen-treated fish have an increased scale number (polymerization), while triidothyronine-treated fish have a reduced scale number (oligomerization). Additionally fish of most prolonged retardation of development (goitrogen-treated) demonstrate phenotype of partially naked skin. This event of reduction of squamation and partial nakedness occurred due to underdevelopment. Also we suggest the regulation of the development by the thyroid hormones is thought to be a perspective approach to mark periods of determination of number of serial elements. [ABSTRACT FROM AUTHOR]

A revised behavioural prediction model integrating components of several psychosocial theories was used to predict men who have sex with mens' (MSM) (N = 139) intentions to always use condoms with their regular partner for anal, oral and vaginal sex. The behavioural model successfully predicted MSMs' condom use intentions for all three behaviours (R = 0.70, R = 0.75 and R = 0.78 for vaginal, anal and oral sex, respectively). Consistent with expectations, the relative importance of the underlying theoretical determinants differed for the three behaviours in question. For condom use for vaginal sex, the partner norm (beta = 0.54) and the mean of the weighted control beliefs (beta = 0.28) were most important. For condom use for anal sex, the partner norm (beta = 0.50), attitude (beta = 0.28) and perceived behavioural control (beta = 0.17) were most important. With respect to oral sex, attitude (beta = 0.51) and partner norm (beta = 0.38) were most important in independently influencing MSMs' intentions to always use condoms. [ABSTRACT FROM AUTHOR]

For research purposes, we single out from the fluid, continuous flux of a child's living activity specific segments that have a certain determinateness and uniformity of content and form and that we shall nominally refer to as play processes, work processes, or other processes. Of course, behavioral segments isolated in this way still remain living processes within a child's activity, under the particular conditions of his environment, and continuous sequences of discrete behavioral acts. Diverse factors contribute to the investment in this activity in one form or another. The differences among the forms of a child's behavior are determined largely by the nature of the bond that serves as the unifying, cementing factor for its discrete, outwardly disjunctive manifestations, and the nature of that bond is determined, in turn, by distinctive features of the interrelations of the organism and the environment. Hence, the first pages of any investigation aspiring to determine the nature and essence of some typical form of a child's behavior must concentrate on study of this bond through which discrete elements of behavior are transformed into integral, organically cohering processes of life activity. However, to study how discrete parts of an organic whole are bonded together and to discover the mechanisms underlying the interdependence of the elements of a whole require determining its "blueprint," its structure. Study of discrete forms of a child's behavior should begin with a structural analysis as well, just as we began our study of children's games, reported on for the first time at the Second All-Russian Congress of Pedology, Experimental Pedagogy, and Psychoneurology, with a structural analysis. [ABSTRACT FROM AUTHOR]

A pronounced pleiotropic effect of thyroid hormones on the regulation of gene expression in fish in postembryogenesis was demonstrated for the first time using larvae and juveniles of the blue bream Ballerus ballerus as an example. Genome-wide transcriptome sequencing (RNA-seq) identified 1212 differentially expressed genes in the brain and liver of fish kept in triiodothyronine solution (0.25 ng/mL). Our data show that the regulation of gene expression by thyroid hormones is widespread in nature: it involves not only the structural genes but also the regulatory genes. A significant number of genes under the control of thyroid hormones are involved in the determination of morphological traits. [ABSTRACT FROM AUTHOR]

Abstract: Characterisation of the effect of food on the bio-performance of modified and extended release dosage forms can be very challenging due to the need to replicate the dynamic biochemical conditions of the human gut as well as the complex physical processing modalities under fed state. Classical compendial methods are useful for testing the quality of pharmaceutical dosage forms but typically have limitations in the accurate prediction of food-effect in-vivo. Preliminary evaluation of the Dynamic Gastric Model (DGM) shows that it can provide substantially more detailed mechanistic information on dosage form properties compared to conventional compendial testing. The potential effect of food on the drug release and physical properties of a hydrophilic matrix formulation containing a model drug, hydrochlorothiazide, was studied using compendial methods, bio-relevant media and the DGM (in combination with an off-line intestinal model). Whilst the compendial methods with biorelevant media provided good correlation with the dissolution rates observed using the DGM/intestinal model under simulated fasted state, the quantification of simulated fed state performance changes was much more challenging using the compendial methods. Classical compendial studies using biorelevant FeSSIF and FaSSIF media could not readily discern differences in dissolution performance under fasted and fed states; however, the DGM could detect significant changes in both physical properties as well as drug release performance under fed state processing. [Copyright &y& Elsevier]

In experiment with hormonal manipulation of developmental rate (alteration of thyroid status) of two cyprinid species, Abramis brama and Rutilus rutilus, we found that number of scales strongly correlates with body size at the moment of first scale appearance. If squamation development starts earlier and at a shorter body length, it results in reduction of scale numbers. If squamation development starts later and at a larger body length, the number of scales is increased. Calculated distances between scales at the moment of their appearance are the same in the different experimental groups despite of acceleration or retardation of developmental rate and a corresponding change in the number of scales (decreasing and increasing). It suggests that size of body at the moment of scale initiation determines the number of scales. Induced heterochrony in initiation of squamation is one of the mechanisms, which is evidently responsible for intraspecies variability in scale numbers and might be considered a relevant reason for differences between close-related species in case of evolutionary fixed heterochronies of scale initiation. Another plausible path for diversity in scale number is a change in distance between forming scales that seems to be more appropriate for species represented phylogenetically more distant lineages. [ABSTRACT FROM AUTHOR]

The genus Rutilus is a widely distributed lineage of cyprinids and ranges from West Europe to East Siberia. Although matrilineal phylogeny and phylogeography of western species were already studied, roaches from remaining part of the range were not examined. Phylogenetic analysis based on cytochrome b sequences detected the following three major phylogenetic clades: (i) R. frisii, (ii) R. rutilus s. str., and (iii) group of six Ponto-Caspian taxa: R. caspicus, R. heckelii, R. rutilus aralensis, R. rutilus lacustris, R. schelkovnikovi, and R. stoumboudae. Our results suggest that these 'species' within Ponto-Caspian clade could be a single species ( R. lacustris by priority of description). The Ponto-Caspian clade is most widely distributed among others and covers the freshwaters from the Aegean Sea basin to Laptev Sea tributaries. Both R. rutilus s. str. and Ponto-Caspian clades sympatrically occur in Black Sea and Caspian Sea basins, Azov Sea itself, and even in drainage of White Sea. The vastest zone of contact (approximately 1700 km) was detected in the Volga basin. The spatial pattern of haplotype diversity and the shape of haplotype network argued for multiple refugia in Ponto-Caspian region as well as a rapid post-glacial colonization of Volga River and Siberia. [ABSTRACT FROM AUTHOR]

Pharmacokinetics of sydnocarb upon the joint administration with ladasten was investigated in rats. Being introduced in this combination, sydnocarb was detected in the blood plasma for a longer time, showed higher values of the distribution coefficients in organs and tissues, and was characterized by a higher bioavailability (112,5%) than upon separate administration in the same dose. [ABSTRACT FROM AUTHOR]