Social Institutions: Classic Understanding and Modern Approaches

The author discusses a sociological understanding of the social institution notion. Analysis of corresponding ideas by E. Durkheim, M. Weber, G. Mead, and T. Parsons reveals various meanings that were con sidered to be scientific milestones. According to classical traditions, institutions are regarded as complex mechanisms for regulation of not uniform inner social orders. Modern institutional approach to social research deals with existing institutional complexes, transform ing institutional conditions and institutional actions by individuals and groups

Вплив вітру на політ некерованих летальних апаратів

This article represents research of influence of wind on flight of uncontrollable flying devices. It is offered the method of taking into account influence of permanent wind as well as baffling wind on flight of uncontrollable aircrafts stabilized with rotation and empennageУ статті проводиться дослідження впливу вітру на політ некерованих летальних апаратів і пропонується метод обліку впливу як постійного, так і перемінного вітру на політ летальних апаратів, які стабілізуються як обертанням, так і крилам

A transcriptome-wide antitermination mechanism sustaining identity of embryonic stem cells

Eukaryotic gene expression relies on extensive crosstalk between transcription and RNA processing. Changes in this composite regulation network may provide an important means for shaping cell type-specific transcriptomes. Here we show that the RNA-associated protein Srrt/Ars2 sustains embryonic stem cell (ESC) identity by preventing premature termination of numerous transcripts at cryptic cleavage/polyadenylation sites in first introns. Srrt interacts with the nuclear cap-binding complex and facilitates recruitment of the spliceosome component U1 snRNP to cognate intronic positions. At least in some cases, U1 recruited in this manner inhibits downstream cleavage/polyadenylation events through a splicing-independent mechanism called telescripting. We further provide evidence that the naturally high expression of Srrt in ESCs offsets deleterious effects of retrotransposable sequences accumulating in its targets. Our work identifies Srrt as a molecular guardian of the pluripotent cell state.</p

Limited receptive area neural classifier for texture recognition of metal surfaces

The Limited Receptive Area (LIRA) neural classifier is proposed for texture recognition of mechanically treated metal surfaces. It can be used in systems that have to recognize position and orientation of complex work pieces in the task of assembly of micromechanical devices. The performance of the proposed classifier was tested on specially created image database in recognition of four texture types that correspond to metal surfaces after:milling, polishing with sandpaper, turning with lathe and polishing with file. The promising recognition rate of 99.7% was obtainedIFIP International Conference on Artificial Intelligence in Theory and Practice - Machine VisionRed de Universidades con Carreras en Informática (RedUNCI

Limited receptive area neural classifier for texture recognition of metal surfaces

The Limited Receptive Area (LIRA) neural classifier is proposed for texture recognition of mechanically treated metal surfaces. It can be used in systems that have to recognize position and orientation of complex work pieces in the task of assembly of micromechanical devices. The performance of the proposed classifier was tested on specially created image database in recognition of four texture types that correspond to metal surfaces after:milling, polishing with sandpaper, turning with lathe and polishing with file. The promising recognition rate of 99.7% was obtainedIFIP International Conference on Artificial Intelligence in Theory and Practice - Machine VisionRed de Universidades con Carreras en Informática (RedUNCI

Time-delayed model of RNA interference

RNA interference (RNAi) is a fundamental cellular process that inhibits gene expression through cleavage and destruction of target mRNA. It is responsible for a number of important intracellular functions, from being the first line of immune defence against pathogens to regulating development and morphogenesis. In this paper we consider a mathematical model of RNAi with particular emphasis on time delays associated with two aspects of primed amplification: binding of siRNA to aberrant RNA, and binding of siRNA to mRNA, both of which result in the expanded production of dsRNA responsible for RNA silencing. Analytical and numerical stability analyses are performed to identify regions of stability of different steady states and to determine conditions on parameters that lead to instability. Our results suggest that while the original model without time delays exhibits a bi-stability due to the presence of a hysteresis loop, under the influence of time delays, one of the two steady states with the high (default) or small (silenced) concentration of mRNA can actually lose its stability via a Hopf bifurcation. This leads to the co-existence of a stable steady state and a stable periodic orbit, which has a profound effect on the dynamics of the system

Effects of transcranial focal electrical stimulation via tripolar concentric ring electrodes on pentylenetetrazole-induced seizures in rats

Purpose: To study the effects of noninvasive transcranial focal electrical stimulation (TFS) via tripolar concentric ring electrodes (TCRE) on the electrographic and behavioral activity from pentylenetetrazole (PTZ)-induced seizures in rats. Methods: The TCREs were attached to the rat scalp. PTZ was administered and, after the first myoclonic jerk was observed, TFS was applied to the TFS treated group. The electroencephalogram (EEG) and behavioral activity were recorded and studied. Results: In the case of the TFS treated group, after TFS, there was a significant (p = 0.001) decrease in power compared to the control group in delta, theta, and alpha frequency bands. The number of myoclonic jerks was significantly different (p = 0.002) with median of 22 and 4.5 for the control group and the TFS treated groups, respectively. The duration of myoclonic activity was also significantly different (p = 0.031) with median of 17.56 min for the control group versus 8.63 min for the TFS treated group. At the same time there was no significant difference in seizure onset latency and maximal behavioral seizure activity score between control and TFS treated groups. Conclusions: TFS via TCREs interrupted PTZ-induced seizures and electrographic activity was reduced toward the “baseline.” The significantly reduced electrographic power, number of myoclonic jerks, and duration of myoclonic activity of PTZ-induced seizures suggests that TFS may have an anticonvulsant effect