Slippery Liquid‐Infused Porous Surfaces that Prevent Microbial Surface Fouling and Kill Non‐Adherent Pathogens in Surrounding Media: A Controlled Release Approach

Many types of slippery liquid‐infused porous surfaces (‘SLIPS’) can resist adhesion and colonization by microorganisms. These ‘slippery’ materials thus offer approaches to prevent fouling on commercial and industrial surfaces. However, while SLIPS can prevent fouling on surfaces to which they are applied, they can currently do little to prevent the proliferation of non‐adherent organisms. Here, multi‐functional SLIPS are reported that address this issue and expand the potential utility of these materials. The approach is based on the release of antimicrobial agents from the porous matrices used to host the infused oil phases. It is demonstrated that SLIPS fabricated from nanoporous polymer multilayers can prevent colonization and biofilm formation by four common fungal and bacterial pathogens, and that the polymer and oil phases comprising these materials can be used to sustain the release of triclosan, a model antimicrobial agent, into surrounding media. This approach improves the inherent anti‐fouling properties of these materials and endows them with the ability to kill non‐adherent pathogens. This strategy has the potential to be general; the strategies and concepts reported here will enable the design of SLIPS with improved anti‐fouling properties and open the door to new applications of slippery liquid‐infused materials that host or release other active agents.     

Gallium Sulfide–Single‐Walled Carbon Nanotube Composites: High‐Performance Anodes for Lithium‐Ion Batteries

Metal sulfides are an important class of functional materials possessing exceptional electrochemical performance and thus hold great promise for rechargeable secondary batteries. In this work, we deposited gallium sulfide (GaS_x, x = 1.2) thin films by atomic layer deposition (ALD) onto single‐walled carbon nanotube (SWCNT) powders. The ALD GaS_x was performed at 150 °C, and produced uniform and conformal amorphous films. The resulting core‐shell, nanostructured SWCNT‐GaS_x composite exhibited excellent electrochemical performance as an anode material for lithium‐ion batteries (LIBs), yielding a stable capacity of ≈575 mA g^–1 at a current density of 120 mA g^–1 in the voltage window of 0.01–2 V, and an exceptional columbic efficiency of >99.7%. The GaS_x component of the composite produced a specific capacity of 766 mA g^–1, a value two times that of conventional graphite anodes. We attribute the excellent electrochemical performance of the composite to four synergistic effects: 1) the uniform and conformal ALD GaS_x coating offers short electronic and Li‐ion pathways during cycling; 2) the amorphous structure of the ALD GaS_x accommodates stress during lithiation‐delithiation processes; 3) the mechanically robust SWCNT framework also accommodates stress from cycling; 4) the SWCNT matrix provides a continuous, high conductivity network.     

Does Electronic Type Matter when Single‐Walled Carbon Nanotubes are Used for Electrode Applications?

Single‐walled carbon nanotube (SWNT) electrodes that are chemically and mechanically robust are fabricated using a simple drop cast method with thermal annealing and acid treatment. An electronic‐type selective decrease in sheet resistance of SWNT electrodes with HNO₃ treatment is shown. Semiconducting SWNTs show a significantly higher affinity toward hole doping in comparison to metallic SWNTs; a ≈12‐fold and a ≈fivefold drop in sheet resistance, respectively. The results suggest the insignificance of the electronic type of the SWNTs for the film conductivity after hole doping. The SWNT films have been employed as transparent hole extracting electrodes in bulk heterojunction (BHJ) organic photovoltaics. Performances of the devices enlighten the fact that the electrode film morphology dominates over the electronic type of the doped SWNTs with similar sheet resistance and optical transmission. The power conversion efficiency (PCE) of 4.4% for the best performing device is the best carbon nanotube transparent electrode incorporated large area BHJ solar cell reported to date. This PCE is 90% in terms of PCEs achieved using indium tin oxide (ITO) based reference devices with identical film fabrication parameters indicating the potential of the SWNT electrodes as an ITO replacement toward realization of all carbon solar cells.     

Engineers and engineering in the US and Japan: a critical review ofthe literature and suggestions for a new research agenda

Researchers have identified a number of interesting differences between engineers and the practice of engineering in Japan and the US (and, to a lesser extent, other countries). They have found that: Japan graduates more engineers per capita than the US; Japanese engineers seem to stay in the practice of engineering longer than their US counterparts; Japanese firms perform more of the post bachelor degree level education and training of engineers than US firms; Japanese universities seem to emphasize teamwork more and business education less than US universities; Japanese firms have less rigid job boundaries than US firms; high performing Japanese firms have more overlap between functions and have developed distinctive ways of handling new product development such as the use of heavy weight project managers. On the other hand, empirical studies so far do not seem to show that "culture" has made much difference in the practice of engineering between the US and Japan. This paper reviews these findings and the implications that have been drawn from them. It goes on to suggest that while this research has provided many useful ideas and models for US managers, in other areas it has stopped short of examining the consequences of what has been found. The result has been the loss of opportunities for policy makers, educators, managers, and social theorists     

S2‐Net: Machine reading comprehension with SRU‐based self‐matching networks

Machine reading comprehension is the task of understanding a given context and finding the correct response in that context. A simple recurrent unit (SRU) is a model that solves the vanishing gradient problem in a recurrent neural network (RNN) using a neural gate, such as a gated recurrent unit (GRU) and long short‐term memory (LSTM); moreover, it removes the previous hidden state from the input gate to improve the speed compared to GRU and LSTM. A self‐matching network, used in R‐Net, can have a similar effect to coreference resolution because the self‐matching network can obtain context information of a similar meaning by calculating the attention weight for its own RNN sequence. In this paper, we construct a dataset for Korean machine reading comprehension and propose an S²‐Net model that adds a self‐matching layer to an encoder RNN using multilayer SRU. The experimental results show that the proposed S²‐Net model has performance of single 68.82% EM and 81.25% F1, and ensemble 70.81% EM, 82.48% F1 in the Korean machine reading comprehension test dataset, and has single 71.30% EM and 80.37% F1 and ensemble 73.29% EM and 81.54% F1 performance in the SQuAD dev dataset.     

nSpace and GeoTime: a VAST 2006 case study.

The nSpace and GeoTime visual analytic tools enable investigation and understanding of complex, ambiguous situations. nSpace is a system of systems supporting the whole analytic workflow. GeoTime provides insight into events and behaviors in time and space. Junior analysts used the analytic capabilities that these tools support to investigate the 2006 Visual Analytics Science and Technology contest data set and to produce an intelligence assessment report. Their work won first place in the corporate category. This article is a detailed case study describing how the nSpace and GeoTime tools created an analytical environment that enabled two novice analysts to examine a scenario, discover patterns, trace connections, assess evidence, visually represent meaningful hypotheses with associated evidence, track progress, collaborate with others, and then produce a final report. nSpace and GeoTime are developed in collaboration with analysts to support the investigation of large and complex multidimensional data sets.     

Spatial frequencies as a medium for guiding attention: Comment on Lamb, Yund, and Pond (1999).

M. R. Lamb, E. W. Yund, and H. M. Pond (see record 1999-00903-005) question the author's earlier arguments that attention can be guided by spatial frequencies when searching for a target in complex visual patterns (L. C. Robertson; see record 1996-05632-001). The 2 major findings they report that are used to argue against the author's conclusions are discussed and found inadequate for the purposes of abandoning this hypothesis. Instead, findings reported in the accompanying article in combination with previous findings reported by 2 of the same authors (M. R. Lamb & E. W. Yund, 1996) provide converging evidence to support spatial frequency as a medium for guiding attention. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Peeling Back the Layers: Controlled Erosion and Triggered Disassembly of Multilayered Polyelectrolyte Thin Films

Methods for the layer‐by‐layer deposition of oppositely charged polymers on surfaces can be used to assemble thin multilayered films using a broad range of natural, synthetic, and biologically relevant materials. These methods also permit precise, nanometer‐scale control over the compositions and internal structures of multicomponent assemblies. Provided that the individual components of these materials are selected or designed appropriately, these methods provide tantalizing new opportunities to design thin films and coatings that provide spatial, temporal, or active control over the release of one or several different agents from surfaces. The last two years have seen a significant increase in reports describing the development of new chemical, physical, and biomolecular approaches to the controlled erosion, triggered disassembly, or general deconstruction of multilayered polymer films. In this Progress Report, we highlight recent work from our laboratory and several other groups toward the design of ultrathin multilayered assemblies that i) permit broad, tunable, and sophisticated control over film erosion, and ii) provide new opportunities for the localized release of macromolecular therapeutics, such as DNA and proteins, from surfaces.     

Reversible Control of Ordering Transitions at Aqueous/Liquid Crystal Interfaces Using Functional Amphiphilic Polymers

On page 4208, Nicholas L. Abbott, David M. Lynn, and coworkers from the University of Wisconsin report amphiphilic polymers that assemble at interfaces between a nematic liquid crystal and immiscible aqueous phases and trigger ordering transitions that result in changes in the optical birefringence of the liquid crystal (as shown). The resulting polymer‐functionalized interfaces respond reversibly to changes in the pH of aqueous solutions and suggest approaches to the design of fluid interfaces that can sense, report on, or respond reversibly to a broad range of environmental stimuli.