Validation of arrayed imaging reflectometry biosensor response for protein-antibody interactions: cross-correlation of theory, experiment, and complementary techniques

One of the critical steps in the development of an analytical technique is to confirm that its experimental response correlates with predictions derived from the theoretical framework on which it is based. This validates the technique quantitatively and, in the case of a biosensor, facilitates a correlation of the sensor's output signal to the concentration of the analyte being tested. Herein we report studies demonstrating that the quantitative response of arrayed imaging reflectometry (AIR), a highly sensitive label-free biosensing method, is a predictable function of the probe and analyte properties. We first incorporated a standard one-site Langmuir binding model describing probe-analyte interactions at the surface into the theoretical model for thickness-dependent reflectance in AIR. This established a hypothetical correlation between the analyte concentration and the AIR response. Spectroscopic ellipsometry, surface plasmon resonance, and AIR were then used to validate this model for two biomedically important proteins, fibroblast growth factor-2 and vascular endothelial growth factor. While our studies demonstrated that the 1:1 one-site Langmuir model accurately described the observed response of macrospot AIR arrays, either a two-site Langmuir model or a Sips isotherm better described the behavior of AIR microarrays. These studies confirmed the quantitative performance of AIR across a range of probe-analyte affinities. Furthermore, the methodology developed here can be extended to other label-free biosensing platforms, thus facilitating a more accurate and quantitative interpretation of the sensor response.     

System identification and controller design for individual pitch and trailing edge flap control on upscaled wind turbines

Active load reduction strategies such as individual pitch control (IPC) and trailing edge flap (TEF) actuation present ways of reducing the fatigue loads on the blades of wind turbines. This may enable development of lighter blades, improving the performance, cost effectiveness and viability of future multi‐megawatt turbine designs. Previous investigations into the use of IPC and TEFs have been limited to turbines with ratings up to 5 MW and typically investigate the use of these load reduction strategies on a single turbine only. This paper extends the design, implementation and analysis of individual pitch and TEFs to a range of classically scaled turbines between 5 and 20 MW. In order to avoid designing controllers which favour a particular scale, identical scale‐invariant system identification and controller design processes are applied to each of the turbines studied. Gain‐scheduled optimal output feedback controllers are designed using identified models to target blade root load fluctuations at the first and second multiples of the rotational frequency using IPC and TEFs respectively. The use of IPC and TEFs is shown in simulations to provide significant reductions in fatigue loads at the blade root. Fatigue loads on non‐rotating components such as the yaw bearing and tower root (yaw moment) are also reduced with the use of TEFs. Individual pitch performance is seen to be slightly lower on larger turbines, potentially due to a combination of reduced actuator bandwidth and movement of the rotational frequency of larger turbines into a more energetic part of the turbulent spectrum. However, TEF performance is consistent irrespective of scale. Copyright © 2015 John Wiley & Sons, Ltd.     

Low-swing current mode logic (LSCML): A new logic style for secure and robust smart cards against power analysis attacks

A new logic style called low-swing current mode logic (LSCML) is presented. It features a dynamic and differential structure and a low-swing current mode operation. The LSCML logic style may be used for hardware implementation of secure smart cards against differential power analysis (DPA) attacks but also for implementation of self-timed circuits thanks to its self-timed operation. Electrical simulations of the Khazad S-box have been carried out in 0.13 μm PD (partially depleted) SOI CMOS technology. For comparison purpose, the Khazad S-box was implemented with the LSCML logic and two other dynamic differential logic styles previously reported. Simulation results have shown an improved reduction of the data-dependent power signature when using LSCML circuits. Indeed the LSCML based Khazad S-box has shown a power consumption standard deviation more than two times smaller than the one in DyCML and almost two times smaller than the one in DDCVSL.     

Methyl methacrylate levels in unwashed salvage blood following unilateral total knee arthroplasty

The short-term results of 1,605 gastrectomies performed for stomach cancer, using different types of esophagoenterostomy, are discussed. Anastomotic leakage is the main criterion for a choice of the most optimal procedure of forming an anastomosis. The contribution of the first and second rows of sutures to leakage is evaluated. An analysis of data on anastomotic leakage incidence points to the advantages offered by application of submerged esophagus-related anastomosis. A new modification of procedure of formation of muffle-type of esophagoenterostomy is presented. Leakage was registered in 1.3% which was due to technical errors during surgery. The non-reflux properties of the anastomosis are emphasized, with particular emphasis on its reliability, good functional characteristics, simplicity and wide range of application. The clinical applications are described.     

Optical switching in the twin-guide Fabry-Perot laser amplifier

A recently developed theory of the twin-guide Fabry-Perot laser amplifier has been extended to include the case of optically induced switching. The effect of feedback from the facets serves to dramatically decrease the optical power required for switching as compared to that for a traveling-wave amplifier, but at the expense of accurate control of input wavelength. Switching is predicted at input powers on the order of microwatts, in good agreement with a first experimental demonstration of the effect     

Development of species sensitivity distributions for wildlife using interspecies toxicity correlation models

Species sensitivity distributions (SSD) are probability distributions of chemical toxicity of multiple species and have had limited application in wildlife risk assessment because of relatively small data sets of wildlife toxicity values. Interspecies correlation estimation (ICE) models predict the acute toxicity to untested taxa from known toxicity of a single surrogate species. ICE models were used to predict toxicity values to wildlife species and generate SSDs for 23 chemicals using four avian surrogates. The hazard levels associated with the fifth percentile of the distribution (HD5) were compared for ICE SSDs and independent SSDs created with measured data. SSDs were composed of either avian only or avian and mammalian taxa. ICE HD5s were within 5-fold of 90% of measured HD5s and were generally higher than measured HD5s. The first percentile of the distribution (HD1) and the fifth percentile of the lower confidence limit (HDL) of ICE SSDs produced values that were not significantly different from measured HD5s. Using a bird surrogate to predicttoxicity to birds and the Norway rat to predict toxicity to mammals improved some estimates of ICE HD5s compared with those generated using only bird surrogates. These results indicate that ICE models can be used to generate SSDs comparable to those derived from measured wildlife toxicity data and provide robust estimates of the HD5.     

FPGA Implementation(s) of a Scalable Encryption Algorithm

SEA is a scalable encryption algorithm targeted for small embedded applications. It was initially designed for software implementations in controllers, smart cards, or processors. In this letter, we investigate its performances in field-programmable gate array (FPGA) devices. For this purpose, a loop architecture of the block cipher is presented. Beyond its low cost performances, a significant advantage of the proposed architecture is its full flexibility for any parameter of the scalable encryption algorithm, taking advantage of generic VHDL coding. The letter also carefully describes the implementation details allowing us to keep small area requirements. Finally, a comparative performance discussion of SEA with the advanced encryption standard Rijndael and (a cipher purposed for efficient FPGA implementations) is proposed. It illustrates the interest of platform/context-oriented block cipher design and, as far as SEA is concerned, its low area requirements and reasonable efficiency.     

1*2 lossless semiconductor optical switch

The addition of curved output guides to a twin-guide laser amplifier switch has enabled the first demonstration to be made of a compact 1*2 semiconductor optical switch that exhibits fibre-to-fibre gain and low crosstalk.<>     

Research in self-management: Applications in school psychology.

One of the most important psychological developments over the past 25 years has been the design of interventions that are, to one degree or another, self-administered. Much of the self-management research has focused on children and school-related problems, making this approach toward assessment and intervention of particular interest and relevance to school psychologists. The three articles in this miniseries reflect new developments in self-management research and practice. Collectively, these articles provide direction for future self-management research as well as break new ground with populations that have received little attention in this area. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The growth of high mobility heterostructures on (311)B GaAs

We demonstrate that the (311)B surface of GaAs can be used for the fabrication of high mobility (μ 2.4 × 10⁶ cm² V⁻¹ s⁻¹) two-dimensional electron gases, in which the mobility is found to be anisotropic with μ_{[ 33]} > μ_{[01 ]}. This paper reviews the magneto-transport properties of the (311)B system and sheds light on the nature of the scattering mechanisms determining the electron mobility. These results are of particular relevance to the current discussion of the nature of the {311} surface.

It is well known that a similar mobility anisotropy exists in hole gases grown on the (311)A surface, although attempts to interpret such results are complicated by the anisotropic and non-parabolic nature of the valence band structure. For electron gases grown on the (311)B surface we demonstrate experimentally (with ballistic focusing) that the Fermi surface is isotropic, leading to the conclusion that the most likely cause of the mobility anisotropy is anisotropic interface roughness scattering. This is also confirmed by measurements of mobility as a function of carrier density, which can be fitted by a simple interface roughness scattering theory.

Further experiments have demonstrated that ballistic quantization can be observed in both [ 33] and [01 ] directions, despite the large differences in anisotropic mobility.