3,890 research outputs found
Balanced ternary addition using a gated silicon nanowire
We demonstrate the proof of principle for a ternary adder using silicon
metal-on-insulator single electron transistors (SET). Gate dependent rectifying
behavior of a single electron transistor results in a robust three-valued
output as a function of the potential of the SET island. Mapping logical,
ternary inputs to the three gates controlling the potential of the SET island
allows us to perform complex, inherently ternary operations, on a single
transistor
Towards a general collisional radiative model
Collisional Radiative Models (CRMs) are a widely used tool in the modelling of plasmas. The results of such models appear as source terms in the particle and energy balances of plasma transport models. Usually such models calculate a partial Quasi Steady State Solution (QSSS). This means that the spatial and temporal relaxation of must excited state densities is neglected, which is valid for a broad variety of plasmas. Recently a new CRM has been developed which combines two interesting properties: * validity for a broad range of electron densities, as stepwise processes are taken into account; * the number of non-QSS levels can be chosen arbitrarily, generalising the concepts of the so-called coefficients of net ionisation and recombination. As a result of these properties it is possible to fully describe radiative transfer, while simultaneously the model is valid for higher electron densities, as stepwise processes can be taken into account. An application of the model is discussed in a second contribution to this conference ('Radiative Transfer in High-Current Ar-Hg Discharges, Van Dijk et el.). Other research groups are kindly invited to participate in this research
Quantum chaos in 2D gravity
We present a quantitative and fully non-perturbative description of the ergodic phase of quantum chaos in the setting of two-dimensional gravity. To this end we describe the doubly non-perturbative completion of semiclassical 2D gravity in terms of its associated universe field theory. The guiding principle of our analysis is a flavor-matrix theory (fMT) description of the ergodic phase of holographic gravity, which exhibits U(n|n) causal symmetry breaking and restoration. JT gravity and its 2D-gravity cousins alone do not realize an action principle with causal symmetry, however we demonstrate that their universe field theory, the Kodaira-Spencer (KS) theory of gravity, does. After directly deriving the fMT from brane-antibrane correlators in KS theory, we show that causal symmetry breaking and restoration can be understood geometrically in terms of different (topological) D-brane vacua. We interpret our results in terms of an open-closed string duality between holomorphic Chern-Simons theory and its closed-string equivalent, the KS theory of gravity. Emphasis will be put on relating these geometric principles to the characteristic spectral correlations of the quantum ergodic phase
The influence of thermo-chemotherapy on bladder tumours: an immunohistochemical analysis
To study the influence of microwave induced thermo-chemotherapy on high-grade urothelial cell carcinomas. Five groups of each three patients were formed of whom initial biopsies and cystectomy samples were collected. Patients were treated 2 days prior to cystectomy with mitomycin-C (group 1), hyperthermia (group 2) or thermo-chemotherapy (group 3). Group 4 patients had been treated with a cycle of six thermo-chemotherapy treatments prior to cystectomy and group 5 patients served as control (no treatment). Tumour samples were stained with Haematoxylin and Eosin, monoclonal antibody Ki-67 and the monoclonal antibody p53. In six out of the nine patients treated with hyperthermia a decrease in proliferation activity in the tumour was found. Seven out of nine patients treated with hyperthermia showed a decrease in p53 activity. A decrease in proliferation activity and p53 activity illustrate the potential role of thermo-chemotherapy as a promising intravesical treatment
Integrability of a conducting elastic rod in a magnetic field
We consider the equilibrium equations for a conducting elastic rod placed in
a uniform magnetic field, motivated by the problem of electrodynamic space
tethers. When expressed in body coordinates the equations are found to sit in a
hierarchy of non-canonical Hamiltonian systems involving an increasing number
of vector fields. These systems, which include the classical Euler and
Kirchhoff rods, are shown to be completely integrable in the case of a
transversely isotropic rod; they are in fact generated by a Lax pair. For the
magnetic rod this gives a physical interpretation to a previously proposed
abstract nine-dimensional integrable system. We use the conserved quantities to
reduce the equations to a four-dimensional canonical Hamiltonian system,
allowing the geometry of the phase space to be investigated through Poincar\'e
sections. In the special case where the force in the rod is aligned with the
magnetic field the system turns out to be superintegrable, meaning that the
phase space breaks down completely into periodic orbits, corresponding to
straight twisted rods.Comment: 19 pages, 1 figur
Crop growth models for the -omics era: the EU-SPICY project
The prediction of phenotypic responses from genetic and environmental information is an area of active research in genetics, physiology and statistics. Rapidly increasing amounts of phenotypic information become available as a consequence of high throughput phenotyping techniques, while more and cheaper genotypic data follow from the development of new genotyping platforms. , A wide array of -omics data can be generated linking genotype and phenotype. Continuous monitoring of environmental conditions has become an accessible option. This wealth of data requires a drastic rethinking of the traditional quantitative genetic approach to modeling phenotypic variation in terms of genetic and environmental differences. Where in the past a single phenotypic trait was partitioned in a genetic and environmental component by analysis of variance techniques, nowadays we desire to model multiple, interrelated and often time dependent, phenotypic traits as a function of genes (QTLs) and environmental inputs, while we would like to include transcription information as well. The EU project 'Smart tools for Prediction and Improvement of Crop Yield' (KBBE-2008-211347), or SPICY, aims at the development of genotype-to-phenotype models that fully integrate genetic, genomic, physiological and environmental information to achieve accurate phenotypic predictions across a wide variety of genetic and environmental configurations. Pepper (Capsicum annuum) is chosen as the model crop, because of the availability of genetically characterized populations and of generic models for continuous crop growth and greenhouse production. In the presentation the objectives and structure of SPICY as well as its philosophy will be discussed
Detection of the tulip breaking virus (TBV) in tulips using optical sensors
The tulip breaking virus (TBV) causes severe economic losses for countries that export tulips such as the Netherlands. Infected plants have to be removed from the field as soon as possible. There is an urgent need for a rapid and objective method of screening. In this study, four proximal optical sensing techniques for the detection of TBV in tulip plants were evaluated and compared with a visual assessment by crop experts as well as with an ELISA (enzyme immunoassay) analysis of the same plants. The optical sensor techniques used were an RGB color camera, a spectrophotometer measuring from 350 to 2500 nm, a spectral imaging camera covering a spectral range from 400 to 900 nm and a chlorophyll fluorescence imaging system that measures the photosynthetic activity. Linear discriminant classification was used to compare the results of these optical techniques and the visual assessment with the ELISA score. The spectral imaging system was the best optical technique and its error was only slightly larger than the visual assessment error. The experimental results appear to be promising, and they have led to further research to develop an autonomous robot for the detection and removal of diseased tulip plants in the open field. The application of this robot system will reduce the amount of insecticides and the considerable pressure on labor for selecting diseased plants by the crop expert. © 2010 The Author(s
Compulsory treatment in patients' homes in the Netherlands: What do mental health professionals think of this?
Background: Compulsory treatment in patients' homes (CTH) will be introduced in the new Dutch mental health legislation. The aim of this study is to identify the opinions of mental health workers in the Netherlands on compulsory community treatment (CCT), and particularly on compulsory treatment in the patients' home. Methods: This is a mixed methods study, comprising a semi-structured interview and a survey. Forty mental health workers took part in the semi-structured interview about CCT and 20 of them, working in outpatient services, also completed a questionnaire about CTH. Descriptive analyses were performed of indicated (dis) advantages and problems of CCT and of mean scores on the CTH questionnaire. Results: Overall, the mental health workers seemed to have positive opinions on CCT. With respect to CTH, all mean scores were in the middle of the range, possibly indicating tha
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