Coarse-Grained Model for Phospholipid/Cholesterol Bilayer

We construct a coarse-grained (CG) model for dipalmitoylphosphatidylcholine (DPPC)/cholesterol bilayers and apply it to large-scale simulation studies of lipid membranes. Our CG model is a two-dimensional representation of the membrane, where the individual lipid and sterol molecules are described by point-like particles. The effective intermolecular interactions used in the model are systematically derived from detailed atomic-scale molecular dynamics simulations using the Inverse Monte Carlo technique, which guarantees that the radial distribution properties of the CG model are consistent with those given by the corresponding atomistic system. We find that the coarse-grained model for the DPPC/cholesterol bilayer is substantially more efficient than atomistic models, providing a speed-up of approximately eight orders of magnitude. The results are in favor of formation of cholesterol-rich and cholesterol-poor domains at intermediate cholesterol concentrations, in agreement with the experimental phase diagram of the system. We also explore the limits of the novel coarse-grained model, and discuss the general validity and applicability of the present approach

Progressing Context in Entrepreneurship Education: Reflections from a Delphi Study

Stimulating entrepreneurial agency among citizens, companies, and organizations is a central objective of many policymakers, potentially requiring arenas for innovation, networks of advisors, training, infrastructure, and finances, among other things. Nonetheless, central to agency is the individual’s own willingness and empowerment to engage. Some aspects of entrepreneurship and entrepreneurial action have been argued to be broadly applicable across disciplines, geographies, and cultures, while others are significantly dependent upon a set of variables in which one is embedded. Thus, considering ways in which the contextual complexity of entrepreneurship (and education) is represented in entrepreneurship education is critical. Recent literature establishes that it is important to design for and with context in entrepreneurship education (Thomassen, et al., International Journal of Entrepreneurial Behavior & Research 26(5):863–886, 2020), but we lack documented knowledge regarding how this can and potentially should be done. In this chapter, we aim to progress a research agenda by identifying current challenges and future opportunities brought forward by experts in entrepreneurship education research through a Delphi study in order to advance the contextualization of entrepreneurship education

Exposing and Utilizing Context in Entrepreneurship Education

Entrepreneurial activity is never void of contextual influence.\ua0 Every new idea, product, process, and venture is embedded in networks of stakeholders, reacts to or reshapes industries, fulfills or changes the needs of customers, while bounded by conditions and driven through the interpretive insight of entrepreneurially acting individuals. Entrepreneurship education needs to empower students learning to act entrepreneurially to embrace this contextual complexity and help to prioritize how to operate in the uncertainty it generates. A recently published literature review conducted by the authors ( Reference anonymous for the review) found that context in entrepreneurship education can be described at multiple levels and structured through sociological phenomena, resulting in a framework to help better understand, prioritize and utilize contextual elements.\ua0 The contribution of this work aims to present this frame translated into a learning tool through which students can grasp, adapt or adjust contextual elements influencing their entrepreneurial activity. Supporting the tool is an interactive design through which educators can stimulate contextual awareness as well as enable prioritization of next steps for students to take based on contextual analysis, and then following action taken, substantiation of decisions made under uncertainty as relating back to contextual elements

Conceptualizing context in entrepreneurship education: a literature review

Purpose: Context impacts the design and practice of entrepreneurship education, but there is limited focus on context in entrepreneurship education literature. The purpose of this paper is to review the entrepreneurship education literature to understand how context has been addressed, derives contextual elements from prioritized literature and explores how context can be adapted to and designed with in entrepreneurship education. Design/methodology/approach: A systematic literature review is undertaken to explore context in entrepreneurship education literature. Context entrepreneurship education yielded 239 items. After refinement, 232 entrepreneurship education associated publications were reviewed by the team of authors. Using selection criteria, 26 prioritized publications were analyzed and categorized according to a theoretical framework. Findings: Context has been addressed both conceptually and empirically, quantitatively and qualitatively, and can be categorized across three sociological phenomena levels – micro, meso and macro. Within these levels, more specific context elements emerge from the entrepreneurship education literature. The findings assert that while context is highly influential in relation to entrepreneurship education, it is arbitrarily described, and holds a variety of documented and diffuse elements. Educators have a limited span of control in relation to context elements, however, for the most parts elements can be adapted to or designed with. Finally, due to the influence of context it is difficult to identify a universal best practice of entrepreneurship education because there simply is no ceteris paribus. Research limitations/implications: Contextual elements which emerged from the literature consider various subjects, spaces, structures and networks. Context is complex and has had limited treatment in entrepreneurship education literature, thus additional analysis and experimentation is necessary. Practical implications: Context shapes understanding and influences learning. Addressing entrepreneurship education across three levels – micro, meso and macro – and through four framing questions – who, what, where and when – guides educators in how context influences and can be used when designing education. Originality/value: The paper gives new insight into how context is addressed in entrepreneurship education literature, and how this can influence educational design.\ua0\ua9 2019, Emerald Publishing Limited

Biophysical and structural characterization of proton-translocating NADH-dehydrogenase (complex I) from the strictly aerobic yeast Yarrowia lipolytica

AbstractMitochondrial proton-translocating NADH-dehydrogenase (complex I) is one of the largest and most complicated membrane bound protein complexes. Despite its central role in eukaryotic oxidative phosphorylation and its involvement in a broad range of human disorders, little is known about its structure and function. Therefore, we have started to use the powerful genetic tools available for the strictly aerobic yeast Yarrowia lipolytica to study this respiratory chain enzyme. To establish Y. lipolytica as a model system for complex I, we purified and characterized the multisubunit enzyme from Y. lipolytica and sequenced the nuclear genes coding for the seven central subunits of its peripheral part. Complex I from Y. lipolytica is quite stable and could be isolated in a highly pure and monodisperse state. One binuclear and four tetranuclear iron–sulfur clusters, including N5, which was previously known only from mammalian mitochondria, were detected by EPR spectroscopy. Initial structural analysis by single particle electron microscopy in negative stain and ice shows complex I from Y. lipolytica as an L-shaped particle that does not exhibit a thin stalk between the peripheral and the membrane parts that has been observed in other systems