Ultrathin Polydopamine Films with Phospholipid Nanodiscs Containing a Glycophorin A Domain

Cellular membranes have long served as an inspiration for nanomaterial research. The preparation of ultrathin polydopamine (PDA) films with integrated protein pores containing phospholipids and an embedded domain of a membrane protein glycophorin A as simplified cell membrane mimics is reported. Large area, ultrathin PDA films are obtained by electropolymerization on gold surfaces with 10–18 nm thickness and dimensions of up to 2.5 cm2. The films are transferred from gold to various other substrates such as nylon mesh, silicon, or substrates containing holes in the micrometer range, and they remain intact even after transfer. The novel transfer technique gives access to freestanding PDA films that remain stable even at the air interfaces with elastic moduli of ≈6–12 GPa, which are higher than any other PDA films reported before. As the PDA film thickness is within the range of cellular membranes, monodisperse protein nanopores, so-called “nanodiscs,” are integrated as functional entities. These nanodisc-containing PDA films can serve as semi-permeable films, in which the embedded pores control material transport. In the future, these simplified cell membrane mimics may offer structural investigations of the embedded membrane proteins to receive an improved understanding of protein-mediated transport processes in cellular membranes

The Art of Research: A Divergent/Convergent Framework and Opportunities for Science-Based Approaches

Applying science to the current art of producing engineering and research knowledge has proven difficult, in large part because of its seeming complexity. We posit that the microscopic processes underlying research are not so complex, but instead are iterative and interacting cycles of divergent (generation of ideas) and convergent (testing and selecting of ideas) thinking processes. This reductionist framework coherently organizes a wide range of previously disparate microscopic mechanisms which inhibit these processes. We give examples of such inhibitory mechanisms and discuss how deeper scientific understanding of these mechanisms might lead to dis-inhibitory interventions for individuals, networks and institutional levels

Declarative expression and optimization of data-intensive flows

Abstract. Data-intensive analytic flows, such as populating a datawarehouse or analyzing a click stream at runtime, are very common in modern business intelligence scenarios. Current state-of-the-art data flow management techniques rely on the users to specify the flow structure without performing automated optimization of that structure. In this work, we introduce a declarative way to specify flows, which is based on annotated descriptions of the output schema of each flow activity. We show that our approach is adequate to capture both a wide-range of arbitrary data transformations, which cannot be supported by traditional relational operators, and the precedence constraints between the various stages in the flow. Moreover, we show that we can express the flows as annotated queries and thus apply precedence-aware query optimization algorithms. We propose an approach to optimizing linear conceptual data flows by producing a parallel execution plan and our evaluation results show that we can speedup the flow execution by up to an order of magnitude compared to existing techniques.

Investigation of CIS/CIGS and CdTe solar cells scribing with high-power fibre short pulse lasers

We present here some of the last results of the EUROPEAN project ALPINE. We present both the development of an adjustable fibre laser pulse source and scribing results on CdTe and CIGS solar cells. The scribing tests were performed at three different pulse durations: 400 fs, 8 ps and 250 ps. The results obtained with 250 ps are already very promising for P3 steps in both CdTe and CIGS solar cells. In both cases the results were validated electrically. In the case of P3 scribing for CIGS solar cells, shunt resistances as high as 125 kΩ.cm were obtained. Isolation resistances were higher than 1 MΩ.cm. The processing speed was 2 m/s