A Multi-Hop Packet-Switched AWGM-Star-Network Realized with TX/RX Arrays

Some of today's optical networks are based on the well known WDM-star topology. In most cases, these are single-hop networks equipped with fast-tuneable wavelength transceivers. For these well studied packet-switched networks, several protocols have been designed. In order to avoid the costs of the fast tuneable devices, a network based on an array waveguided multiplexer (AWGM) and arrays of non-tuneable or slow tuneable transmitters and receivers is suggested. In order to enable communication among all stations, a multi-hop environment is introduced which is determined by the AWGM routing matrix. In the case of slow-tuneable devices, the topology can be reconfigured in dependence on changing traffic patterns. In order to get a first insight into the performance of these topologies, we focus on the case of fixed transceiver units and an uniformly distributed traffic matrix.     

The reliability of self-image change scores in psychotherapy research: An application of generalizability theory.

The aim of this study was to estimate the reliability of the pre- to posttreatment change scores for 3 different self-image aspects, Attack, Love, and Control. To measure self-image, we used the Norwegian version of the introject surface of Benjamin's (1974) structural analysis of social behavior. The article introduces Generalizability (G-) theory, combined with the recent concept of tolerance for error, as a framework for estimating the reliability and precision of change scores in 1- and 2-facet designs. Data were obtained from the Norwegian Multi-Site Study of Process and Outcome in Psychotherapy, including 291 outpatients. The mean number of treatment sessions was 47. The results show that change scores may be highly reliable. Generalizability coefficients resting on the relative and absolute score interpretations, respectively, for both the Love and Attack change scores reached acceptable levels. The reliability of the Control change score was, however, poor. G-theory combined with the error-tolerance concept proved to be a helpful framework for assessing the dependability of change scores in a psychotherapy research setting. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Solid‐State Approach for Fabrication of Photostable,Oxygen‐Doped Carbon Nanotubes

A novel procedure for effective fabrication of photostable oxygen‐doped single‐walled carbon nanotubes (SWCNTs) in solid‐state matrices has been developed. SWCNTs drop‐cast on various types of substrates are coated with oxide dielectric thin films by electron‐beam evaporation. Single tube photoluminescence spectroscopy studies performed at room and cryogenic temperatures reveal that such thin film‐coated tubes exhibit characteristic spectral features of oxygen‐doped SWCNTs, indicating the oxide thin film coating process leads to oxygen doping of the tubes. It is also found that the doping efficiency can be effectively controlled by the thin film deposition time and by the types of surfactants wrapping the SWCNTs. Moreover, aside from being the doping agent, the oxide thin film also serves as a passivation layer protecting the SWCNTs from the external environment. Comparing the thin film coated SWCNTs with oxygen‐doped tubes prepared via ozonolysis, the former exhibit significantly higher photostability and photoluminescence on‐time. Therefore, this one‐step deposition/oxygen‐doping procedure provides a possible route toward scalable, versatile incorporation of highly photostable oxygen‐doped SWCNTs in novel optical and optoelectronic devices.     

Melt processed PLA/PCL blends: Effect of processing method on phase structure,morphology, and mechanical properties

Poly(lactic acid) (PLA)‐rich poly(lactic acid)/poly(ε‐caprolactone) (PLA/PCL) blends were melt‐blended at different compositions. The compositions such as 90/10 and 80/20 were obtained using three different blending methods and processed by injection molding and hot pressing. All blends were immiscible. The crystallinity of PLA increased slightly in the presence of poly(ε‐caprolactone) (PCL), and the PCL exhibited fractionated crystallization in the presence of PLA. Injection molded specimens, compared with hot pressed specimens, presented much smaller PCL particles regardless of the blending method used. Some interfacial adhesion was observed in all cases. The stiffness of PLA/PCL blends decreased as the PCL content was increased and was independent of processing. Injection molded specimens showed ductile behavior and broke at elongation values close to 140%, while the elongation at break of the hot pressed specimens was clearly lower, most likely due to the larger size of the PCL particles. Although the impact strength of the blends remained low, it improved by approximately 200% with 30% PCL and by 350% with 40% PCL. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42641.     

Low‐Temperature Control of Twins and Abnormal Grain Growth in BaTiO3

The microstructure of polycrystalline barium titanate (BaTiO₃) thin films processed with a liquid‐phase can be controlled by the crystallographic orientation of the underlying sapphire substrate. During postdeposition crystallization, the tendency for {111} twin nucleation, which drives subsequent abnormal grain growth, depends upon the specific sapphire facet. Specifically, tilting away from the close‐packed c‐plane modifies the orientation, morphology, and relative amount of an interfacial BaAl₂O₄ second phase. These factors control the density of twin formation, and thus overall grain size of the crystallized BaTiO₃. As the substrate orientation transitions from c‐plane, to r‐plane, to a‐plane, the twin density is reduced, the average grain size decreases systematically from 270 to 130 nm, and the grain structure becomes overall more homogeneous. This twinning mechanism and abnormal grain growth occur by 900°C, several hundred degrees lower than reported previously.     

Environmentally sustainable development: a life-cycle costing approach for a commercial office building in Melbourne,Australia

A range of property and construction options is analysed using standard life-cycle costing methodology. The options are to renovate the existing building, buy an alternative building and renovate, and buy a development site and construct a new building. The do-nothing option and a hypothetical option to construct a new building on an ideal site are analysed as benchmarks. The results show that the optimum option is to buy a suitable site and construct a new building and that the least sustainable option, in the case study, is to stay in the existing property and renovate the building. Although staying in the existing building and doing nothing carries the lowest financial cost, energy consumption and greenhouse emissions are significantly worse than for the alternative options.     

Modulation of Biointeractions by Electrically Switchable Oligopeptide Surfaces: Structural Requirements and Mechanism

Understanding the dynamic behavior of switchable surfaces is of paramount importance for the development of controllable and tailor‐made surface materials. Herein, electrically switchable mixed self‐assembled monolayers based on oligopeptides have been investigated in order to elucidate their conformational mechanism and structural requirements for the regulation of biomolecular interactions between proteins and ligands appended to the end of surface tethered oligopeptides. The interaction of the neutravidin protein to a surface appended biotin ligand was chosen as a model system. All the considerable experimental data, taken together with detailed computational work, support a switching mechanism in which biomolecular interactions are controlled by conformational changes between fully extended (“ON” state) and collapsed (“OFF” state) oligopeptide conformer structures. In the fully extended conformation, the biotin appended to the oligopeptide is largely free from steric factors allowing it to efficiently bind to the neutravidin from solution. While under a collapsed conformation, the ligand presented at the surface is partially embedded in the second component of the mixed SAM, and thus sterically shielded and inaccessible for neutravidin binding. Steric hindrances aroused from the neighboring surface‐confined oligopeptide chains exert a great influence over the conformational behaviour of the oligopeptides, and as a consequence, over the switching efficiency. Our results also highlight the role of oligopeptide length in controlling binding switching efficiency. This study lays the foundation for designing and constructing dynamic surface materials with novel biological functions and capabilities, enabling their utilization in a wide variety of biological and medical applications.