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McPherson’s Blau space and affiliation ecology model is a powerful tool for analyzing the ecological competition among social entities, such as organizations, along a combination of sociodemographic characteristics of their members. In this paper we introduce the R-based Graphical User Interface (GUI) package Blaunet, an integrated set of tools to calculate, visualize, and analyze the statuses of individuals and social entities in Blau space, parameterized by multiple sociodemographic traits as dimensions. The package is able to calculate the Blau statuses at the nodal, dyadic, and meso levels based on three types of information: sociodemographic characteristics, group affiliations (e.g., membership in groups/organizations), and network ties. To facilitate this, Blaunet has the following five main capabilities, it can: 1) identify a list of possible salient dimensions; 2) calculate, plot, and analyze niches for social entities by measuring the social distance along the salient dimensions between individuals affiliated with them; 3) generate Blau bubbles for individuals, thereby allowing the study of interpersonal influence of similar others even with limited or no network information; 4) capture niche dynamics cross-sectionally by calculating the intensity of exploitation from the carrying capacity and the membership rate; and 5) analyze the niche movement longitudinally by estimating the predicted niche movement equations. We illustrate these capabilities of Blaunet with example datasets. [ABSTRACT FROM AUTHOR]

A long line of research documents the essential role of social networks in mediating the recruitment and retention of members in organizations. But organizations also comprise a primary context where people form social ties. We investigate how the network structure an organization creates among its members influences its ability to grow and reproduce. In particular, we propose that two dimensions of organizational strategy influence affiliation dynamics: (1) the extent to which an organization induces social interaction among its members (social encapsulation), and (2) the time and energy that an organization demands of its members (time and energy demand). We examine membership dynamics in an ecology where competitor organizations deploying varied strategies vie for the same pool of members. Results show a curvilinear relationship between membership growth and the rate of social encapsulation. Furthermore, we find that time and energy demand mediates the effect of social encapsulation by shaping its members' opportunities for maintaining external affiliations. Different opportunity structures result in different levels of network turnover, thus either reinforcing or dissolving intra-organizational ties. For most types of organizations, attaining sustained growth requires a balance between open networks (for recruitment) and network closure (for retention). [ABSTRACT FROM AUTHOR]

Oil was employed as an 'entrance door' for loading rubber with carbon-based fillers of different size and dimensionalities: 1D carbon nanotubes (CNTs), 2D graphene nanoplatelets (GNPs), and 3D graphite. This approach was explored, as a proof of concept, in the preparation of tire tread, where oil is commonly used to reduce the viscosity of the composite mixture. Rubber was loaded with carbon black (CB, always used) and one or more of the above fillers to enhance the thermal and mechanical properties of the composite. The CNT-loaded system showed the best enhancement in mechanical properties, followed by the CNT-GNP one. Rubber loaded with both graphite and GNP showed the best enhancement in thermal conductivity (58%). The overall enhancements in both mechanical and thermal properties of the various systems were analyzed through an overall relative efficiency index in which the total filler concentration in the system is also included. According to this index, the CNT-loaded system is the most efficient one. The oil as an 'entrance door' is an easy and effective novel approach for loading fillers that are in the nanoscale and provide high enhancement of properties at low filler concentrations. [ABSTRACT FROM AUTHOR]