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Silver-based grating structures offer means for implementing low-cost, efficient grating couplers for use in surface plasmon resonance (SPR) sensors. One-dimensional grating structures with a fixed periodicity are confined to operate effectively within a single planar orientation. However, two-dimensional grating structures as well as grating structures with variable periodicity allow for the plasmon excitation angle to be seamlessly adjusted. This study demonstrates silver-based grating designs that allow for the plasmon excitation angle to be adjusted via rotation or beam position. The flexible angle adjustment opens up the possibility of developing SPR sensor designs with an expanded dynamic range and increased flexibility in sensing applications. The results demonstrate that efficient coupling into two diffraction orders is possible, which ultimately leads to an excitation angle range from 16° to 40° by rotating a single structure. The findings suggest a promising direction for the development of versatile and adaptable SPR sensing platforms with enhanced performance characteristics. [ABSTRACT FROM AUTHOR]

A complex envelope approach for the numerical solution of Maxwell's equations based on Faber polynomial expansions is investigated. The Faber polynomial expansion used for the approximation of the exponential time propagator offers a highly accurate and efficient calculation while allowing the application of large time steps. The complex envelope approach incorporates only the envelope around a carrier frequency. This is especially beneficial when bandlimited source field distributions are investigated as it is the case for many applications from terahertz technology or photonics. [ABSTRACT FROM AUTHOR]

The stationary and transient behavior of a 3 nm wide on-insulator type FinFET is investigated. The focus is laid on the evaluation and characterization of the effect of quantum confinement on the amplifier behavior. The high computational burden related to the time-resolved analysis of such three-dimensional simulations is dealt with by applying a mode-space approach onto a Quantum Liouville-type Equation. It is shown that the diagonal coupling terms related to the mode-space approach should be taken into consideration for the analysis of FinFETs. An increase in gain compression and higher order harmonic distortion is observed, when the fin height is decreased and, therefore, stronger quantum confinement occurs. The 1 dB compression point is shown to decrease by as much as 8 dB when reducing the fin height from 7 to 3 nm. • A coupled mode-space approach is applied onto a Liouville-type equation. • The new algorithm enables efficient transient analysis of Multigate-FETs. • Here, nonlinear behavior in nanoscale FinFETs is investigated in the time-domain. • Gain compression is shown to increase when reducing the channel size. [ABSTRACT FROM AUTHOR]

Approximations based on Faber polynomials for the numerical solution of Maxwell’s equations in the time domain are investigated. The exponential convergence properties of the Faber polynomials allow to construct highly accurate time propagation schemes with time steps exceeding the Courant–Friedrichs–Lewy stability limit by several orders of magnitude. Additional material models, such as Drude and Lorentz models, and, moreover, perfectly matched layers to truncate the computational domain are included using additional differential equations. A novel approach to approximate the spectrum of the system matrix is introduced to enable the Faber polynomial expansions for arbitrary device models. [ABSTRACT FROM AUTHOR]

A time-dependent discontinuous Galerkin method for the numerical solution of the Liouville–von-Neumann equation in center mass coordinates for the analysis of quantum transport in nanoelectronics and nanophotonics systems is presented. With this methodology, a further increase in computational efficiency compared to conventional methods is achieved, particularly when considering large-scale problems. • Discontinuous Galerkin Method for the approximation of the Liouville–von-Neumann Equation. • Time efficient solution of the Liouville–von-Neumann Equation. • Method allowing the use of High-Performance Computing approaches. • Extension of the DG method enables the analysis of complex quantum devices. [ABSTRACT FROM AUTHOR]

The gain compression and excitation of higher order harmonics in 3 nm wide on-insulator type FinFETs is investigated. The high computational burden related to the time-resolved analysis of such three-dimensional devices is dealt with by applying a mode-space approach onto a Quantum Liouville-type Equation. With this approach an increase in gain compression and higher order harmonic distortion is observed when decreasing the fin height from 5 to 3 nm. • A coupled mode-space approach is applied onto a Liouville-type equation. • The new algorithm enables efficient transient analysis of Multigate-FETs. • Here, nonlinear behavior in nanoscale FinFETs is investigated in the time-domain. • Gain compression is shown to increase when reducing the channel size. [ABSTRACT FROM AUTHOR]

The application of the Wigner–Veyl transform for the analysis of quantum transport effects leads to several difficulties and to criticism. One of the difficulties is the numerical discretization of the Wigner transport equations, after the Wigner–Veyl transform is applied onto the statistical density matrix as a part of the quantum Liouville equation. The conventional discretization methods are based on a finite-difference approximation of the resulting Wigner transport equation applying upwind difference schemes or hybrid difference schemes. The results obtained do not match with the statistical density matrix based on the solution of the Schrödinger equation. The contribution addresses the difficulties when the conventional discretization approaches are applied. The difficulties arising from this approach are discussed, and the prerequisites for an improved approach are defined. On the basis of this discussion and the conclusions obtained, a new approach is proposed. This approach is based on an evaluation of the characteristics of the Wigner transport equation in the eigenvalue domain. The new approach is discussed and is applied onto a standard resonant tunneling diode structure. The numerical results are compared with the results from the application of the conventional techniques. [ABSTRACT FROM AUTHOR]

The use of surface plasmon resonance sensors allows for the fabrication of highly sensitive, label-free analytical devices. This contribution reports on a grating coupler to enable surface plasmon resonance studies using silver on silicon oxide technology to build long-term stable plasmonic structures for biological molecule sensing. The structural parameters were simulated and the corresponding simulation model was optimized based on the experimental results to improve its reliability. Based on the model, optimized grating nanostructures were fabricated on an oxidized silicon wafer with different structural parameters and characterized using a dedicated optical setup and scanning electron microscopy. The combined theoretical and experimental results show that the most relevant refractive index range for biological samples from 1.32–1.46 may conveniently be covered with a highest sensitivity of 128.85°/RIU. [ABSTRACT FROM AUTHOR]

Background Stump neuroma pain in amputees can be quite challenging. Surgical treatment may be largely subdivided into neuromodulative and non-neuromodulative methods. The latter includes neurocapsis, insertion of nerve stump into the bone marrow, centro-central short circuit (CCSC), and coverage with vascularized soft tissue flaps. CCSC was shown to be extremely effective in alleviation of pain. Reports on CCSC for the treatment of stump neuroma pain have disappeared from the literature, with a shift toward neuromodulation for the treatment of pain irrespective of etiology. Methods We observed 8 lower limb amputees undergoing CCSC of the sciatic nerve during a follow-up of 12 years. All had the same stump neuroma pain rendering them unable to wear their prostheses. The sciatic nerve was explored at the midthigh area, much proximal to the amputation site, and a short circuit was established between the tibial and peroneal parts of the nerve. Assessment was by means of pain quantification as per the quadruple visual analogue scale, medication intake, and ability to use prostheses. Results The median worst quadruple visual analogue scale before surgery was 8.0. After surgery it decreased to 2.5 ( P = 0.00094). Medication intake was reduced from regular intake of a combination of opioids, nonsteroidal anti-inflammatory drugs, tricyclic antidepressants, and pregabalin in all patients to irregular intake of nonsteroidal anti-inflammatory drug alone in 3 of 8 patients. All patients were able to wear their limb prosthesis since surgery. Conclusions CCSC is a simple, effective, and long-lasting method to treat painful stump neuromas in amputees. It should be strongly considered in deserving cases before resorting to neuromodulative methods. [ABSTRACT FROM AUTHOR]

The modal analysis is needed for the design of photonic waveguide devices to determine propagation constants of guided modes and their field pattern. Rigorous methods based on finite-difference or finite-element methods for the approximation of wave equations rely on the solution of eigenvalue problems. Imaginary-distance beam propagation methods require the solution of matrix equations of high order. The computation time needed for both approaches can be tedious. A modal analysis method based on a beam propagation scheme is proposed, which allows an efficient computation of field patterns and propagation constants, as the resulting algorithm is based on simple matrix vector multiplications. This allows the choice of a large number of discretization points and a dense discretization. The beam propagation operator is designed to include the eigenvalue spectrum of corresponding guided modes only. For this reason, the method can be interpreted as a subdomain propagation method. The concept will be validated by utilizing a single-mode and multimode rib waveguide. [ABSTRACT FROM AUTHOR]

Abstract: A design strategy is presented for a symmetrical 3-port lumped element circulator. By applying a numerical time domain method metallisations that are several high, and via-holes can be modelled with high accuracy. Furthermore, parasitic elements are implicitly included, and the numerical analysis provides valuable information about important device performances. Therefore, the application of the presented strategy allows the numerical analysis of very compact devices built by using thin film technology. For comparison with measured scattering parameters the device performance of an optimised circulator is numerically calculated. Measured scattering parameters agree very well with the calculation results. [Copyright &y& Elsevier]

The problem of learning maps with mobile robots has received considerable attention over the past years. Most of the approaches, however, assume that the environment is static during the data-acquisition phase. In this paper we consider the problem of creating maps with mobile robots in populated environments. Our approach uses a probabilistic method to track multiple people and to incorporate the estimates of the tracking technique into the mapping process. The resulting maps are more accurate since the number of spurious objects is reduced and since the robustness of range registration is improved. Our approach has been implemented and tested on real robots in indoor and outdoor scenarios. We present several experiments illustrating the capabilities of our approach to generate accurate two- and three-dimensional maps. [ABSTRACT FROM AUTHOR]

One of the goals in the field of mobile robotics is the development of mobile platforms which operate in populated environments. For many tasks it is therefore highly desirable that a robot can track the positions of the humans in its surrounding. Itt this paper we introduce sample-based joint probabilistic data association filters as a new algorithm to track multiple moving objects. Our method applies Bayesian filtering to adapt the tracking process to the number of objects in the perceptual range of the robot. The approach has been implemented and tested on a real robot using laser-range data. We present experiments illustrating that our algorithm is able to robustly keep track of multiple people. The experiments furthermore show that the approach outperforms other techniques developed so far. [ABSTRACT FROM AUTHOR]

Presents a probabilistic technique for estimating the state of dynamic objects in the environment of a mobile service robot. Incorporation of the robot's uncertainty in its position into the state estimation process; Implementation of the method on a real robot; Examples to illustrate the efficiency and robustness of the method.

Investigates the optical properties of quantum wells. Calculation of the dielectric function of these quantum wells; Details on the application of the coherent wave approach; Examination of Schrodinger equation based on the envelope function approximation; Statistical data compiled in this investigation.

Due to the advancements of robotic systems, they are able to be employed in more unstructured outdoor environments. In such environments the robot–terrain interaction becomes a highly non-linear function. Several methods were proposed to estimate the robot–terrain interaction: machine learning methods, iterative geometric methods, quasi-static and fully dynamic physics simulations. However, to the best of our knowledge there has been no systematic evaluation comparing those methods. In this paper, we present a newly developed iterative contact point estimation method for static stability estimation of actively reconfigurable robots. This new method is systematically compared to a physics simulation in a comprehensive evaluation. Both interaction models determine the contact points between robot and terrain and facilitate a subsequent static stability prediction. Hence, they can be used in our state space global planner for rough terrain to evaluate the robot’s pose and stability. The analysis also compares deterministic versions of both methods to stochastic versions which account for uncertainty in the robot configuration and the terrain model. The results of this analysis show that the new iterative method is a valid and fast approximate method. It is significantly faster compared to a physics simulation while providing good results in realistic robotic scenarios. [ABSTRACT FROM AUTHOR]

Rhizosphere-associated Streptomyces sp. AcH 505 (AcH 505) promotes infection of Norway spruce ( Picea abies) with the pathogenic fungus Heterobasidion abietinum 331, while Streptomyces sp. GB 4-2 (GB 4-2) enhances spruce defense against the fungus. To identify whether these bacteria influence the availability of the fungal phytotoxin fomannoxin and hence spruce infection, we analyzed the fomannoxin yield in H. abietinum 331-AcH 505 dual cultures. Further, the fate of fomannoxin was studied by adding the compound to cultures of AcH 505, GB 4-2 and nine other soil streptomycetes. Culture filtrates were extracted with ethyl acetate and analyzed by HPLC. Structures of novel compounds were elucidated by HPLC-HR-ESI-Orbitrap-MS and NMR spectroscopy. Phytotoxicity of the compounds was determined by in vivo measurement of maximum photosystem II efficiency of Arabidopsis thaliana seedlings. The amount of fomannoxin in H. abietinum 331-AcH 505 dual cultures was reduced compared to axenic fungus cultures and fungus-plant dual cultures. Following addition of fomannoxin to AcH 505 cultures, the compound disappeared and three novel fomannoxin derivatives without phytotoxic activity were detected. Another novel compound, fomannoxin amide, was discovered following fomannoxin addition to GB 4-2 cultures. Nine other streptomycetes converted fomannoxin into fomannoxin acid or fomannoxin amide. Both compounds exhibit the same phytotoxicity as fomannoxin. We, thus, conclude that the streptomycete-mediated modulation of spruce infection with H. abietinum 331 does not depend on the availability of fomannoxin. We further add evidence to the observation that the lipophilic side chain of fomannoxin is an important structural element for its phytotoxicity. [ABSTRACT FROM AUTHOR]

Objectives: To describe long-term food availability and prices from 1961 to 2007 and body mass index (BMI) trends from 1980 to 2010 in Samoa, and to contextualize these trends within political, economic, cultural, behavioral, and climatic influences. Methods: National level data on food availability and pricing were obtained from the open access database FAO (). Data for Samoa were collected from annual food balance sheets available for the period 1961-2007. Mean BMI for Samoan men and women aged 35-44 years of age is reported from four different time periods, 1979-1982, 1991, 2003, and 2010. Results: Total energy availability increased substantially, by 47%, with more than 900 extra calories available per capita per day in 2007 than in 1961. Many of these extra calories are supplied by dietary fat, the availability of which rose by a proportionally greater amount, 73%. Availability of both meat and vegetable oils rose substantially. Poultry meat increased the most proportionally, from 10 to 117 kcal per capita per day. Coconut products, fruits, and starchy root crops-all locally grown-showed little to no increase over this time. As import prices for poultry and mutton increased their availability decreased, but the availability of vegetable oils rose despite a rise in their price. Mean BMI for men and women aged 35-44 years rose 18% rise from 1980 to 2010. Conclusions: These long-term trends in food availability and prices, and the temporal pattern of BMI provide national level data for understanding the process of the nutritional transition in Samoa. Further work on consumer food prices, diet, food security, and health is needed to further contextualize the transformation of the local food system in Samoa. Samoa. Am. J. Hum. Biol., 2012. © 2012 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Presents a dynamical simulation of the transient effects of quantum wells semiconductor device structures at high frequencies. Fundamental equations describing semiconductor electrical properties; Quantum optical phenomena; Interband density matrix formalism in real-space representation.

Background: Patients' treatment expectations are a key factor in psychotherapy. Several studies have linked higher expectations to better treatment success. Therefore, we want to evaluate the impact of a targeted video-based intervention on patients' expectations and the treatment success of inpatient rehabilitation.Methods/design: All patients who will be referred to inpatient psychosomatic rehabilitation in three clinics will receive a study flyer with information about how to log in to the study platform together with the usual clinic information leaflet. Patients will receive the study information and informed consent upon login and will be randomized into the intervention or the control group. The intervention group (n = 394) will get access to our virtual online clinic, containing several videos about inpatient rehabilitation, until their admission to inpatient rehabilitation. The control group (n = 394) will receive no special treatment preparation. Questionnaires will be given at study inclusion (T0), two weeks before admission to (T1), and at the end of (T2) inpatient rehabilitation. The primary outcome is the outcome expectancy measured with the Credibility Expectancy Questionnaire at T1. Secondary outcomes include treatment motivation, mental health, work ability, depression, anxiety, and satisfaction with and usage of the Internet platform.Discussion: We expect the intervention group to benefit from the additional preparation concerning their outcome expectancy. If successful, this approach could be used in the future to enhance the efficacy of inpatient rehabilitation.Trial Registration: ClinicalTrials.gov: NCT02532881 . Registered on 25 August 2015. [ABSTRACT FROM AUTHOR]

A randomised, open label phase III trial was conducted to evaluate efficacy of nimotuzumab, a monoclonal antibody against epidermal growth factor receptor (EGF-R) added to standard therapy for newly diagnosed glioblastoma. 149 glioblastoma patients stratified as with or without residual tumour were randomly assigned to receive either intravenous nimotuzumab 400 mg weekly added to standard radiochemotherapy followed by 400 mg biweekly after twelve weeks or standard radiochemotherapy. Progression status after 52 weeks (12moPFS) and progression-free survival (PFS) based on Macdonald criteria were co-primary and overall survival (OS), toxicity and quality of life secondary end-points. 142 patients were evaluated for efficacy (per protocol cohort). 12moPFS was 25.6% in the experimental arm and 20.3% in the control group. In residual tumour patients (n = 81) median PFS was 5.6 versus 4.0 months, (hazard ratio (HR), 0.87; 95% confidence interval (CI), 0.55–1.37), for patients without residual tumour (n = 61) it was 10.6 versus 9.9 months, (HR, 1.01; 95% CI, 0.57–1.77). Median OS in patients with residual tumour was 19.5 versus 16.7 months, (HR, 0.90; 95% CI, 0.52–1.57; P = 0.7061), for patients without 23.3 versus 21.0 months (HR, 0.77; 95% CI, 0.41–1.44; P = 0.4068). A small cohort of MGMT non-methylated patients with residual tumour showed PFS of 6.2 versus 4.0 months (HR, 0.77; 95% CI, 0.35–1.67; P = 0.4997) and OS of 19.0 versus 13.8 months (HR, 0.66; 95% CI, 0.27–1.64; P = 0.3648). EGF-R amplification did not correlate with clinical efficacy of nimotuzumab. Nimotuzumab was well tolerated. This study, albeit negative, contains hypothesis generating signals supporting evaluation of correlative, efficacy-predicting tumour parameters for nimotuzumab in the treatment of glioblastoma. [ABSTRACT FROM AUTHOR]

Purpose A randomised, open label phase III trial was conducted to evaluate efficacy of nimotuzumab, a monoclonal antibody against epidermal growth factor receptor (EGF-R) added to standard therapy for newly diagnosed glioblastoma. Patients and methods 149 glioblastoma patients stratified as with or without residual tumour were randomly assigned to receive either intravenous nimotuzumab 400 mg weekly added to standard radiochemotherapy followed by 400 mg biweekly after twelve weeks or standard radiochemotherapy. Progression status after 52 weeks (12moPFS) and progression-free survival (PFS) based on Macdonald criteria were co-primary and overall survival (OS), toxicity and quality of life secondary end-points. Results 142 patients were evaluated for efficacy (per protocol cohort). 12moPFS was 25.6% in the experimental arm and 20.3% in the control group. In residual tumour patients ( n = 81) median PFS was 5.6 versus 4.0 months, (hazard ratio (HR), 0.87; 95% confidence interval (CI), 0.55–1.37), for patients without residual tumour ( n = 61) it was 10.6 versus 9.9 months, (HR, 1.01; 95% CI, 0.57–1.77). Median OS in patients with residual tumour was 19.5 versus 16.7 months, (HR, 0.90; 95% CI, 0.52–1.57; P = 0.7061), for patients without 23.3 versus 21.0 months (HR, 0.77; 95% CI, 0.41–1.44; P = 0.4068). A small cohort of MGMT non-methylated patients with residual tumour showed PFS of 6.2 versus 4.0 months (HR, 0.77; 95% CI, 0.35–1.67; P = 0.4997) and OS of 19.0 versus 13.8 months (HR, 0.66; 95% CI, 0.27–1.64; P = 0.3648). EGF-R amplification did not correlate with clinical efficacy of nimotuzumab. Nimotuzumab was well tolerated. Conclusion This study, albeit negative, contains hypothesis generating signals supporting evaluation of correlative, efficacy-predicting tumour parameters for nimotuzumab in the treatment of glioblastoma. [ABSTRACT FROM AUTHOR]

Abstract: Multi-robot systems obtain their performance advantages from close collaboration of the participating robot systems. As the demand for such cooperation increases, the aspect of wireless communication is getting more and more important. To cope with the challenges of the wireless communication we propose an easy to use communication framework for a multi-robot system. This framework is designed for wireless networks, therefore it expects unreliable communication and can even cope with complete network separations. Using multicast as the default communication scheme, the framework can directly benefit from the broadcast nature of the wireless medium if such an optimisation is supported by the lower network protocols. We therefore introduce our multicast capable wireless routing protocol, which supports this optimisation. The software is implemented and frequently used in our experimental multi-robot system. [Copyright &y& Elsevier]