Variation in the Structure of Bird Nests between Northern Manitoba and Southeastern Ontario

Traits that converge in appearance under similar environmental conditions among phylogenetically independent lineages are thought to represent adaptations to local environments. We tested for convergence in nest morphology and composition of birds breeding in two ecologically different locations in Canada: Churchill in northern Manitoba and Elgin in southeastern Ontario. We examined nests from four families of passerine birds (Turdidae: Turdus, Parulidae: Dendroica, Emberizidae: Passerculus and Fringillidae: Carduelis) where closely related populations or species breed in both locations. Nests of American Robins, Yellow Warblers, and Carduelis finches had heavier nest masses, and tended to have thicker nest-walls, in northern Manitoba compared with conspecifics or congenerics breeding in southeastern Ontario. Together, all species showed evidence for wider internal and external nest-cup diameters in northern Manitoba, while individual species showed varying patterns for internal nest-cup and external nest depths. American Robins, Yellow Warblers, and Carduelis finches in northern Manitoba achieved heavier nest masses in different ways. American Robins increased all materials in similar proportions, and Yellow Warblers and Common Redpolls used greater amounts of select materials. While changes in nest composition vary uniquely for each species, the pattern of larger nests in northern Manitoba compared to southeastern Ontario in three of our four phylogenetically-independent comparisons suggests that birds are adapting to similar selective pressures between locations

Inferring the Transcriptional Landscape of Bovine Skeletal Muscle by Integrating Co-Expression Networks

Background: Despite modern technologies and novel computational approaches, decoding causal transcriptional regulation remains challenging. This is particularly true for less well studied organisms and when only gene expression data is available. In muscle a small number of well characterised transcription factors are proposed to regulate development. Therefore, muscle appears to be a tractable system for proposing new computational approaches. Methodology/Principal Findings: Here we report a simple algorithm that asks "which transcriptional regulator has the highest average absolute co-expression correlation to the genes in a co-expression module?" It correctly infers a number of known causal regulators of fundamental biological processes, including cell cycle activity (E2F1), glycolysis (HLF), mitochondrial transcription (TFB2M), adipogenesis (PIAS1), neuronal development (TLX3), immune function (IRF1) and vasculogenesis (SOX17), within a skeletal muscle context. However, none of the canonical pro-myogenic transcription factors (MYOD1, MYOG, MYF5, MYF6 and MEF2C) were linked to muscle structural gene expression modules. Co-expression values were computed using developing bovine muscle from 60 days post conception (early foetal) to 30 months post natal (adulthood) for two breeds of cattle, in addition to a nutritional comparison with a third breed. A number of transcriptional landscapes were constructed and integrated into an always correlated landscape. One notable feature was a 'metabolic axis' formed from glycolysis genes at one end, nuclear-encoded mitochondrial protein genes at the other, and centrally tethered by mitochondrially-encoded mitochondrial protein genes. Conclusions/Significance: The new module-to-regulator algorithm complements our recently described Regulatory Impact Factor analysis. Together with a simple examination of a co-expression module's contents, these three gene expression approaches are starting to illuminate the in vivo transcriptional regulation of skeletal muscle development

Relationship between supply chain integration and performance

This study analyzes survey-based studies examining the benefits of supply chain integration (SCI) and presents opportunities for further empirical examination. The literature review method is used to evaluate the empirical research published from 1990 to 2012. The analysis reveals that internal integration serves as a foundation for establishing external collaboration. There is empirical evidence on the positive effect of supplier integration on performance, whereas the findings on benefits through customer integration are conflicting. While researchers have made significant progress in our understanding of SCI, there is a substantial need for more work to provide in-depth insights into the potential of SCI and to improve the methodological issues. This study makes three contributions. First, this study expands the current understanding of benefits and considerations in implementing internal, supplier, and customer integration. Second, this study provides a critique of the empirical work and offers research agendas that can stimulate future researchers to carefully explore the topic. Finally, this study enhances the quality of analysis by employing the five-step approach proposed by Vokurka and O\u27Leary-Kelly (J Oper Manag 18(4):485-501, 2000). © 2013 Springer Science+Business Media New York

Purchasing Involvement in Discontinuous Innovation: An Emerging Research Agenda

International audienceBuilding on a systematic review of the literature, we define and discuss why and how purchasing needs to be involved in the discontinuous innovation process. We argue that purchasing involvement in NPD should be considered mainly when the customer firm faces discontinuous innovation. Seeking to promote this emerging research agenda, we present three propositions to focus future studies and inspire practices: (a) technology sourcing and scanning out of the boundary of the supply base is an important stake to support discontinuous innovation as (b) to form an ambidextrous purchasing organization and (c) to develop absorptive capacity within purchasing function. The paper concludes by summarizing the conceptual implications of the paper, outlining some initial managerial recommendations

The antecedents and innovation outcomes of firms’ absorptive capacity in global buyer–supplier relationships

This article seeks to address two fundamental questions: (1) Does social capital (SC) embedded in global buyer–supplier (GBS) relationships enhance local firms’ potential absorptive capacity (PAC) and realized absorptive capacity (RAC)? And (2) What are the effects of local firms’ PAC and RAC on their innovation outcomes? Based on survey data collected from 297 Chinese firms engaged in GBS cooperation in China’s Yangtze River Delta region, we test our research hypotheses with the structural equation modelling approach. The empirical findings indicate that both structural and relational SC are important antecedents of PAC and RAC in global buyer–supplier relationships. More specifically, RAC not only improves local suppliers’ new product performance, but also fully mediates the relationship between PAC and new product performance. Our results have two major implications for practicing managers. First, local suppliers in emerging economies need to pay more attention to SC embedded in GBS relationships for it is an important means for them to overcome resource constraints and therefore to improve their new product performance. Second, it is important for managers in local firms to continuously improve their PAC to better assess and assimilate external knowledge, and extend their RAC to upgrade their interpretation and comprehension of commercialization possibilities, which allows for generating synergy of knowledge recombination with existing core competencies