1,304 research outputs found
Control of apple scab by curative applications of biocontrol agents
In organic apple growing protective applications with copper, sulphur or lime sulphur are
used for apple scab control. Protective applications have to be repeated when new leaves
unfold. The timing of protective sprays depends on the weather forecast. If forecasted
infection conditions fail to appear, treatments were for nothing. With curative control
agents available, the number of treatments could be reduced. In greenhouse trials we
tested control agents for their protective and curative efficiency against apple scab after
artificial inoculation of potted apple trees. Applications were done 2 hours before
inoculation, 5 hours after inoculation on wet leaves, 5 hours after inoculation during
simulated rainfall or 24 hours after inoculation on wet or dry leaves. The optimal time of
application differed between the preparations tested. Vitisan and OmniProtect had their
highest activity when sprayed curative 24 hours after inoculation. Combinations were
found, which revealed a high efficiency against apple scab from 2h before to 24 hours after
inoculation. In a field trial apple scab was effectively controlled by curative applications of
OmniProtect
Chinese politeness is not about 'face': Evidence from the business world
Through reviewing the historical development of the English term face and the Chinese terms mianzi and lian, and drawing upon examples of the use of the terms mianzi and lian in the business domain in mainland China and explanations of negotiations in which the author has been personally involved, this paper argues that mianzi and lian (and by reference 'face') are not sub-concepts lying essentially at the heart of Chinese politeness, but separate concepts which, while overlapping with politeness in some instances, frequently operate in ways which are entirely removed from any accepted notions of politeness. In this way, this paper claims that concern for mianzi and lian in Chinese business interaction is just as likely to engender acts of impoliteness as it is to link with examples of politeness, and concludes that the sooner we accept the disassociation between Chinese 'face' and politeness, the more we will find ourselves better placed to understand crucial nuances of cross-cultural interaction between Chinese and non-Chinese interactants
A multidisciplinary survey of modeling techniques for biochemical networks
All processes of life are dominated by networks of interacting biochemical components. The purpose of modeling these networks is manifold. From a theoretical point of view it allows the exploration of network structures and dynamics, to find emergent properties or to explain the organization and evolution of networks. From a practical point of view, in silico experiments can be performed that would be very expensive or impossible to achieve in the laboratory, such as hypothesis-testing with regard to knockout experiments or overexpression, or checking the validity of a proposed molecular mechanism.
The literature on modeling biochemical networks is growing rapidly and the motivations behind different modeling techniques are sometimes quite distant from each other. To
clarify the current context, we present a systematic overview of the different philosophies to model biochemical networks. We put particular emphasis on three main domains which have been playing a major role in the past, namely: mathematics with ordinary and partial differential equations, statistics with stochastic simulation algorithms, Bayesian networks and Markov chains, and the field of computer science with process calculi, term rewriting
systems and state based systems.
For each school, we evaluate advantages and disadvantages such as the granularity of representation, scalability, accessibility or availability of analysis tools. Following this, we describe how one can combine some of those techniques and thus take advantages of several techniques through the use of bridging tools. Finally, we propose a next step for modeling biochemical networks by using artificial chemistries and evolutionary computation.
This work was funded by ESIGNET (Evolving Cell Signaling Networks in Silico), an European Integrated Project in the EU FP6 NEST Initiative (contract no. 12789)
Calculation of the separation streamlines of barchans and transverse dunes
We use FLUENT to calculate the wind profile over barchans and transverse
dunes. The form of the streamlines of flow separation at the lee side of the
dunes is determined for a symmetric barchan dune in three dimensions, and for
the height profile of a measured transverse dune field in the Len\c{c}\'ois
Maranhenses.Comment: 6 pages including 5 figures. Proceedings of PSIS 200
Seismic properties of the crust and uppermost mantle of North America
Seismic refraction profiles for the North American continent were compiled. The crustal models compiled data on the upper mantle seismic velocity (P sub n), the crustal thickness (H sub c) and the average seismic velocity of the crystalline crust (V sub p). Compressional wave parameters were compared with shear wave data derived from surface wave dispersion models and indicate an average value for Poisson's ratio of 0.252 for the crust and of 0.273 for the uppermost mantle. Contour maps illustrate lateral variations in crustal thickness, upper mantle velocity and average seismic velocity of the crystalline crust. The distribution of seismic parameters are compared with a smoothed free air anomaly map of North America and indicate that a complidated mechanism of isostatic compensation exists for the North American continent. Several features on the seismic contour maps also correlate with regional magnetic anomalies
A miniature piston-cylinder apparatus for high-pressure X-ray diffraction in conjunction with energy dispersion
On the Nature of Incompressible Magnetohydrodynamic Turbulence
A novel model of incompressible magnetohydrodynamic turbulence in the
presence of a strong external magnetic field is proposed for explanation of
recent numerical results. According to the proposed model, in the presence of
the strong external magnetic field, incompressible magnetohydrodynamic
turbulence becomes nonlocal in the sense that low frequency modes cause
decorrelation of interacting high frequency modes from the inertial interval.
It is shown that the obtained nonlocal spectrum of the inertial range of
incompressible magnetohydrodynamic turbulence represents an anisotropic
analogue of Kraichnan's nonlocal spectrum of hydrodynamic turbulence. Based on
the analysis performed in the framework of the weak coupling approximation,
which represents one of the equivalent formulations of the direct interaction
approximation, it is shown that incompressible magnetohydrodynamic turbulence
could be both local and nonlocal and therefore anisotropic analogues of both
the Kolmogorov and Kraichnan spectra are realizable in incompressible
magnetohydrodynamic turbulence.Comment: Physics of Plasmas (Accepted). A small chapter added about 2D MHD
turbulenc
Inertial range scaling in numerical turbulence with hyperviscosity
Numerical turbulence with hyperviscosity is studied and compared with direct
simulations using ordinary viscosity and data from wind tunnel experiments. It
is shown that the inertial range scaling is similar in all three cases.
Furthermore, the bottleneck effect is approximately equally broad (about one
order of magnitude) in these cases and only its height is increased in the
hyperviscous case--presumably as a consequence of the steeper decent of the
spectrum in the hyperviscous subrange. The mean normalized dissipation rate is
found to be in agreement with both wind tunnel experiments and direct
simulations. The structure function exponents agree with the She-Leveque model.
Decaying turbulence with hyperviscosity still gives the usual t^{-1.25} decay
law for the kinetic energy, and also the bottleneck effect is still present and
about equally strong.Comment: Final version (7 pages
Spontaneous Raman scattering for simultaneous measurements of in-cylinder species
A technique for multi-species mole fraction measurement in internal combustion engines is described. The technique is based on the spontaneous Raman scattering. It can simultaneously provide the mole fractions of several species of N-2, O-2, H2O, CO2 and fuel. Using the system, simultaneous measurement of air/fuel ratio and burnt residual gas are carried out during the mixture process in a Controlled Auto Ignition (CAI) combustion engine. The accuracy and consistency of the measured results were confirmed by the measured air fuel ratio using an exhaust gas analyzer and independently calculated mole fraction values. Measurement of species mole fractions during combustion process has also been demonstrated. It shows that the SRS can provide valuable data on this process in a CAI combustion engine
Rotational Correlation Functions of Single Molecules
Single molecule rotational correlation functions are analyzed for several
reorientation geometries. Even for the simplest model of isotropic rotational
diffusion our findings predict non-exponential correlation functions to be
observed by polarization sensitive single molecule fluorescence microscopy.
This may have a deep impact on interpreting the results of molecular
reorientation measurements in heterogeneous environments.Comment: 5 pages, 4 figure
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