Dynamics of Small Group: Microgroup Theory Approach

AbstractThe concept of ‘group dynamics’ should be concretized by means of certain processes and phenomena. This concretization depends on the framework employed by a researcher. In the context of a microgroup theory group dynamics is conceived as transformation of socio-psychological group structure, i.e., of informal subgroups and non-involved-in-them members, their relations with each other and with a group as a whole. The basis of the group dynamics is composed of contradictions (self- transformation source) and the related processes of integration and disintegration (self-transformation mechanism) in structure and external activity of a group

Structural transitions in the transcription elongation complexes of bacterial RNA polymerase during σ-dependent pausing

A transcription initiation factor, the σ70 subunit of Escherichia coli RNA polymerase (RNAP) induces transcription pausing through the binding to a promoter-like pause-inducing sequence in the DNA template during transcription elongation. Here, we investigated the mechanism of σ-dependent pausing using reconstituted transcription elongation complexes which allowed highly efficient and precisely controlled pause formation. We demonstrated that, following engagement of the σ subunit to the pause site, RNAP continues RNA synthesis leading to formation of stressed elongation complexes, in which the nascent RNA remains resistant to Gre-induced cleavage while the transcription bubble and RNAP footprint on the DNA template extend in downstream direction, likely accompanied by DNA scrunching. The stressed complexes can then either break σ-mediated contacts and continue elongation or isomerize to a backtracked conformation. Suppressing of the RNAP backtracking decreases pausing and increases productive elongation. On the contrary, core RNAP mutations that impair RNAP interactions with the downstream part of the DNA template stimulate pausing, presumably by destabilizing the stressed complexes. We propose that interplay between DNA scrunching and RNAP backtracking may have an essential role in transcription pausing and its regulation in various systems

Multiple roles of the RNA polymerase β′ SW2 region in transcription initiation, promoter escape, and RNA elongation

Interactions of RNA polymerase (RNAP) with nucleic acids must be tightly controlled to ensure precise and processive RNA synthesis. The RNAP β′-subunit Switch-2 (SW2) region is part of a protein network that connects the clamp domain with the RNAP body and mediates opening and closing of the active center cleft. SW2 interacts with the template DNA near the RNAP active center and is a target for antibiotics that block DNA melting during initiation. Here, we show that substitutions of a conserved Arg339 residue in the Escherichia coli RNAP SW2 confer diverse effects on transcription that include defects in DNA melting in promoter complexes, decreased stability of RNAP/promoter complexes, increased apparent KM for initiating nucleotide substrates (2- to 13-fold for different substitutions), decreased efficiency of promoter escape, and decreased stability of elongation complexes. We propose that interactions of Arg339 with DNA directly stabilize transcription complexes to promote stable closure of the clamp domain around nucleic acids. During initiation, SW2 may cooperate with the σ3.2 region to stabilize the template DNA strand in the RNAP active site. Together, our data suggest that SW2 may serve as a key regulatory element that affects transcription initiation and RNAP processivity through controlling RNAP/DNA template interactions

Real-time Monitoring for the Next Core-Collapse Supernova in JUNO

Core-collapse supernova (CCSN) is one of the most energetic astrophysical events in the Universe. The early and prompt detection of neutrinos before (pre-SN) and during the SN burst is a unique opportunity to realize the multi-messenger observation of the CCSN events. In this work, we describe the monitoring concept and present the sensitivity of the system to the pre-SN and SN neutrinos at the Jiangmen Underground Neutrino Observatory (JUNO), which is a 20 kton liquid scintillator detector under construction in South China. The real-time monitoring system is designed with both the prompt monitors on the electronic board and online monitors at the data acquisition stage, in order to ensure both the alert speed and alert coverage of progenitor stars. By assuming a false alert rate of 1 per year, this monitoring system can be sensitive to the pre-SN neutrinos up to the distance of about 1.6 (0.9) kpc and SN neutrinos up to about 370 (360) kpc for a progenitor mass of 30$M_{\odot}$ for the case of normal (inverted) mass ordering. The pointing ability of the CCSN is evaluated by using the accumulated event anisotropy of the inverse beta decay interactions from pre-SN or SN neutrinos, which, along with the early alert, can play important roles for the followup multi-messenger observations of the next Galactic or nearby extragalactic CCSN.Comment: 24 pages, 9 figure

Potential of Core-Collapse Supernova Neutrino Detection at JUNO

JUNO is an underground neutrino observatory under construction in Jiangmen, China. It uses 20kton liquid scintillator as target, which enables it to detect supernova burst neutrinos of a large statistics for the next galactic core-collapse supernova (CCSN) and also pre-supernova neutrinos from the nearby CCSN progenitors. All flavors of supernova burst neutrinos can be detected by JUNO via several interaction channels, including inverse beta decay, elastic scattering on electron and proton, interactions on C12 nuclei, etc. This retains the possibility for JUNO to reconstruct the energy spectra of supernova burst neutrinos of all flavors. The real time monitoring systems based on FPGA and DAQ are under development in JUNO, which allow prompt alert and trigger-less data acquisition of CCSN events. The alert performances of both monitoring systems have been thoroughly studied using simulations. Moreover, once a CCSN is tagged, the system can give fast characterizations, such as directionality and light curve

Detection of the Diffuse Supernova Neutrino Background with JUNO

As an underground multi-purpose neutrino detector with 20 kton liquid scintillator, Jiangmen Underground Neutrino Observatory (JUNO) is competitive with and complementary to the water-Cherenkov detectors on the search for the diffuse supernova neutrino background (DSNB). Typical supernova models predict 2-4 events per year within the optimal observation window in the JUNO detector. The dominant background is from the neutral-current (NC) interaction of atmospheric neutrinos with 12C nuclei, which surpasses the DSNB by more than one order of magnitude. We evaluated the systematic uncertainty of NC background from the spread of a variety of data-driven models and further developed a method to determine NC background within 15\% with {\it{in}} {\it{situ}} measurements after ten years of running. Besides, the NC-like backgrounds can be effectively suppressed by the intrinsic pulse-shape discrimination (PSD) capabilities of liquid scintillators. In this talk, I will present in detail the improvements on NC background uncertainty evaluation, PSD discriminator development, and finally, the potential of DSNB sensitivity in JUNO

<b>Functions of Informal Subgroups in Relation to Working Groups and Group </b><b>Effectiveness</b>

A comparative analysis of the degree to which informal subgroups implement three specific functions in relation to the work ingroup (performing group tasks, organizing group activities, and positioning and influence within the group) has been carried out, and the direct and indirect connections of these functions of subgroups with group social and performance effectiveness have been investigated. Forty-four work groups, containing 63 informal subgroups (varying from one to three per participating group), took part in the study. </p

Relationships between Employees’ Identifications and Citizenship Behavior in Work Groups: The Role of the Regularity and Intensity of Interactions

This paper explores the relationships of various employees’ identifications (personal, interpersonal, micro-group, group and organizational) in their two components (cognitive and affective) with two dimensions of organizational citizenship behavior (OCB): offering quality ideas and suggestions, and providing help and support within small work groups. Two studies were conducted in Russia on two respective samples: (1) employees of commercial enterprises (N = 183) characterized by a relatively high regularity and intensity of within-group interactions; and (2) the academic staff of higher education institutions (N = 157), which typically have relatively less regular, low-intensity within-group interactions. The research employed four questionnaires to assess the participants’ identifications in both of their components. In addition, managers in the respective organizations filled out an organizational communicativeness questionnaire and a two-factor OCB assessment instrument. It was found that the relationships between (a) particular identifications and (b) the ratio of group identification to other identifications, on the one hand, and OCB, on the other, depend on the degree of regularity of within-group interactions, as well as on the identification components. Organizational communicativeness did not moderate the relationship between identifications and OCB, but was significantly positively correlated with both OCB dimensions. The theoretical and practical implications of the study findings are discussed

Multiple Identifications of Employees in an Organization: Salience and Relationships of Foci and Dimensions

This research addresses: (1) the salience of employees’ social (organizational, sub-organizational, group, micro-group), interpersonal, and personal identifications and their dimensions (cognitive and affective); (2) and the relationship and structure of the identifications of employees in different areas of professional activity. The study was conducted on independent samples of employees in the socio-economic sphere (241 participants), in the law enforcement agency (265), and in higher education (172). To assess the respective identification foci and dimensions, the study employed four questionnaires. The personal identification was the weakest and the micro-group identification was the strongest for both dimensions in all samples. The affective dimension prevails over the cognitive in all identifications, except for interpersonal. Social identifications were significantly positively correlated to each other in all samples whereas personal identification was significantly negatively correlated with all social identifications (on the affective dimension) in two samples. The results expand our understanding of the identifications of employees in organizations