Functional Peptide Monolayers at Interfaces

Amphiphilic peptides can be designed to form ordered supramolecular structures at hydrophilic-hydrophobic interfaces. These systems rely on the ability of peptides to fold into certain secondary structures at interfaces. This review focuses on the design of amphiphilic β-sheet peptide assemblies in monolayers at interfaces, and their relevance to inducing mineralization and interactions with specific ions. In addition, the review discusses recent studies demonstrating the applicability of designed amphiphilic β-sheet peptides to detection of specific small molecules and to elucidating intermolecular interactions relevant to drug delivery and enzyme catalysis systems.     

Electrical Characterization of Individual Cesium Lead Halide Perovskite Nanowires Using Conductive AFM

Perovskite nanostructures have attracted much attention in recent years due to their suitability for a variety of applications such as photovoltaics, light-emitting diodes (LEDs), nanometer-size lasing, and more. These uses rely on the conductive properties of these nanostructures. However, electrical characterization of individual, thin perovskite nanowires has not yet been reported. Here, conductive atomic force microscopy characterization of individual cesium lead halide nanowires is presented. Clear differences are observed in the conductivity of nanowires containing only bromide and nanowires containing a mixture of bromide and iodide. The differences are attributed to a higher density of crystalline defects, deeper trap states, and higher inherent conductivity for nanowires with mixed bromide–iodide content.     

Highly Conductive Thin Uniform Gold‐Coated DNA Nanowires

Over the past decades, DNA, the carrier of genetic information, has been used by researchers as a structural template material. Watson‐Crick base pairing enables the formation of complex 2D and 3D structures from DNA through self‐assembly. Various methods have been developed to functionalize these structures for numerous utilities. Metallization of DNA has attracted much attention as a means of forming conductive nanostructures. Nevertheless, most of the metallized DNA wires reported so far suffer from irregularity and lack of end‐to‐end electrical connectivity. An effective technique for formation of thin gold‐coated DNA wires that overcomes these drawbacks is developed and presented here. A conductive atomic force microscopy setup, which is suitable for measuring tens to thousands of nanometer long molecules and wires, is used to characterize these DNA‐based nanowires. The wires reported here are the narrowest gold‐coated DNA wires that display long‐range conductivity. The measurements presented show that the conductivity is limited by defects, and that thicker gold coating reduces the number of defects and increases the conductive length. This preparation method enables the formation of molecular wires with dimensions and uniformity that are much more suitable for DNA‐based molecular electronics.     

High Performance Core/Shell Ni/Ni(OH)2 Electrospun Nanofiber Anodes for Decoupled Water Splitting

Decoupled water splitting is a promising new path for renewable hydrogen production, offering many potential advantages such as stable operation under partial-load conditions, high-pressure hydrogen production, overall system robustness, and higher safety levels. Here, the performance of electrospun core/shell nickel/nickel hydroxide anodes is demonstrated in an electrochemical-thermally activated chemical decoupled water splitting process. The high surface area of the hierarchical porous electrode structure improves the utilization efficiency, charge capacity, and current density of the redox anode while maintaining high process efficiency. The anodes reach average current densities as high as 113 mA cm⁻² at a working potential of 1.48 V_RHE and 64 mA cm⁻² at 1.43 V_RHE, with a Faradaic efficiency of nearly 100% and no H₂/O₂ intermixing in a membrane-free cell.     

Marketing through research: William Caudill and Caudill,Rowlett, Scott (CRS)

The partners of Caudill Rowlett Scott (CRS), a post-Second World War architecture firm in Texas, USA, were especially innovative in their professional and business practices. One of their original contributions was the firm's marketing strategy, which was based on promoting not only design achievements but also the CRS ‘research attitude’ by publishing and distributing studies produced by members of the firm. This strategy, which built on a wide-spread American belief in the fundamental role of science and research in the nation's progress and development, was successful in the first two decades of the firm, but was dissolved in the 1970s with the firm's expansion and transformation into a profit-oriented enterprise. This paper describes the firm's research-based marketing strategy and argues that the success of the marketing strategy relied on the CRS partners' ability first, to integrate marketing into the firm's approach to architecture and design and into cultural norms of the time and secondly, to balance the expectations of both their potential clients and their professional peers. The CRS marketing strategy is an important case study for architects today as they respond creatively to similarly competing demands.     

Should we care about neutrality in the city?

Neutrality in political philosophy is a contested idea. The paper argues that there are valid moral reasons to incorporate neutrality in spatial organization considerations, by appealing to universal reasons rather than sectarian reasons. This is a view that defends ‘justificatory neutrality’. The paper responds to previous concerns regarding the applicability of neutrality in the spatial sphere, arguing that the conception of justificatory neutrality successfully addresses these concerns. Yet, the paper raises doubts whether the arguments that persist in the current political philosophy literature can or should, at the end of the day, be applied to the spatial sphere.     

Marketing through research: William Caudill and Caudill,Rowlett, Scott (CRS)

The partners of Caudill Rowlett Scott (CRS), a post-Second World War architecture firm in Texas, USA, were especially innovative in their professional and business practices. One of their original contributions was the firm's marketing strategy, which was based on promoting not only design achievements but also the CRS ‘research attitude’ by publishing and distributing studies produced by members of the firm. This strategy, which built on a wide-spread American belief in the fundamental role of science and research in the nation's progress and development, was successful in the first two decades of the firm, but was dissolved in the 1970s with the firm's expansion and transformation into a profit-oriented enterprise. This paper describes the firm's research-based marketing strategy and argues that the success of the marketing strategy relied on the CRS partners' ability first, to integrate marketing into the firm's approach to architecture and design and into cultural norms of the time and secondly, to balance the expectations of both their potential clients and their professional peers. The CRS marketing strategy is an important case study for architects today as they respond creatively to similarly competing demands.     

Lymphatic Connexins and Pannexins in Health and Disease

This review highlights current knowledge on the expression and function of connexins and pannexins, transmembrane channel proteins that play an important role in intercellular communication, in both the developing and mature lymphatic vasculature. A particular focus is given to the involvement of these proteins in functions of the healthy lymphatic system. We describe their influence on the maintenance of extracellular fluid homeostasis, immune cell trafficking to draining lymph nodes and dietary nutrient absorption by intestinal villi. Moreover, new insights into connexin mutations in primary and secondary lymphedema as well as on the implication of lymphatic connexins and pannexins in acquired cardiovascular diseases are discussed, allowing for a better understanding of the role of these proteins in pathologies linked to dysfunctions in the lymphatic system.     

Explaining counterexamples using causality

When a model does not satisfy a given specification, a counterexample is produced by the model checker to demonstrate the failure. A user must then examine the counterexample trace, in order to visually identify the failure that it demonstrates. If the trace is long, or the specification is complex, finding the failure in the trace becomes a non-trivial task. In this paper, we address the problem of analyzing a counterexample trace and highlighting the failure that it demonstrates. Using the notion of causality introduced by Halpern and Pearl, we formally define a set of causes for the failure of the specification on the given counterexample trace. These causes are marked as red dots and presented to the user as a visual explanation of the failure. We study the complexity of computing the exact set of causes, and provide a polynomial-time algorithm that approximates it. We then analyze the output of the algorithm and compare it to the one expected by the definition. The algorithm is implemented as a feature in the IBM formal verification platform RuleBase PE, where the visual explanations are an integral part of every counterexample trace. Our approach is independent of the tool that produced the counterexample, and can be applied as a light-weight external layer to any model checking tool, or used to explain simulation traces.