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171.
The Wageningen Delivery of Functionality symposium covered all aspects involved with food structural design to arrive at high-quality
foods which meet demanding customer expectations and regulatory requirements. The symposium integrated aspects from the structural
organization of foods at molecular and supramolecular scales to dedicated techniques required to describe and visualize such
structures, the gastro-intestinal events and how to model these in a laboratory setting, and finally the impact those food
structures and ingredients have on the consumer’s physiology and on the human perception. As an interdisciplinary platform,
bringing together more than 160 researchers from academia and industry, the symposium meanwhile fulfills an important role
in the food science community. 相似文献
172.
The Kelvin-Helmholtz instability is investigated analytically by using a one-dimensional nonuniform model of the Earth’s magnetosphere
and the adjacent solar wind region. Its properties are shown to be essentially governed by the presence of an MHD cavity that
arises in the magnetosphere because of the non-uniformity of the latter and also because of the jump in the parameters of
the medium at the magnetopause (the outer boundary of the magnetosphere). System oscillations constitute a discrete spectrum
of eigenmodes, which are determined by the wave vector k
t
along the tangential discontinuity and also by the mode number n = 0, 1, 2, …, playing the role of the wavenumber along a coordinate normal to the magnetopause. Analytic expressions are
obtained for the frequency and instability growth rate of each eigenmode and for the functions describing its spatial structure.
All these quantities depend parametrically on the solar wind velocity V
W
, or more precisely, on the Doppler frequency shift ω
W
= k
t
· V
W
. For each eigenmode, there is a lower instability threshold depending on the parameter ω
W
and a sharp maximum in the growth rate at the eigenfrequency of the magnetospheric cavity. For ω
W
values below the threshold, the properties of an eigenmode are highly sensitive to the type of solar wind nonuniformity.
Three cases are considered: a uniform solar wind and solar winds in which the speed of sound increases or decreases away from
the magnetopause. 相似文献
173.
Evergreen boreal plant species express high variability in their leaf traits. It remains controversial whether this within-species
variability is constrained to the same leaf trait relationships as has been observed across species. We sampled leaves of
three boreal evergreen woody species along a latitudinal gradient (from 57o56′N to 69o55′N). Leaf longevity (LL) of Pinus sylvestris L. and Vaccinium vitis-idaea L. correlated negatively with mean annual air temperature (MAT), whereas the LL of Ledum palustre L. was not affected by MAT. V. vitis-idaea and L. palustre had a negative relationship between leaf mass per area (LMA) and MAT. In P. sylvestris, the LMA–MAT relationship was positive. A negative correlation between LL and LMA was significant only for P. sylvestris. Leaf nitrogen concentration was positively related to leaf phosphorus concentration in all three species. Leaf potassium
concentration was related to nitrogen concentration only in L. palustre, and to phosphorus concentration in P. sylvestris and L. palustre. Our results demonstrate that although within the studied species the variation in some of the leaf traits may have the same
degree as interspecific variation, there is no such intercorrelation of leaf traits within the studied species as has been
observed across species. 相似文献
174.
175.
176.
177.
Biophysics - The effects of the separate and combined action of lead nitrate in a wide range of doses, uranyl nitrate, and chronic low-dose gamma irradiation on the formation of oxidative stress in... 相似文献
178.
Zubareva O. E. Melik-Kasumov T. B. 《Journal of Evolutionary Biochemistry and Physiology》2021,57(4):743-760
Journal of Evolutionary Biochemistry and Physiology - A large proportion of patients with epilepsy suffer from pharmacoresistant forms of the disease, and this makes the search for new treatments... 相似文献
179.
Blazhevich L. E. Smirnova O. E. Kirilina V. M. Krivchenko A. I. 《Journal of Evolutionary Biochemistry and Physiology》2021,57(4):953-961
Journal of Evolutionary Biochemistry and Physiology - The article addresses the role of TNF-α, IL-2, IL-5 and IL-6 in the contractile activity of rat tracheal and bronchial smooth muscle... 相似文献
180.
A. Franz B. Ronacher 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》2002,188(4):261-271
The vast majority of animals are poikilotherms, and thus face the problem that the temperature of their nervous systems rather smoothly follows the temperature changes imposed by their environment. Since basic properties of nerve cells, e.g., the time constants of ion channels, strongly depend on temperature, a temperature shift likely affects the processing of the temporal structure of sensory stimuli. This can be critical in acoustic communication systems in which time patterns of signals are decisive for recognition by the receiver. We investigated the temperature dependence of the responses of locust auditory receptors and interneurons by varying the temperature of the experimental animals during intracellular recordings. The resolution of fast amplitude modulations of acoustic signals was determined in a gap detection paradigm. In auditory receptors and local (second order) interneurons, temporal resolution was improved at higher temperatures. This gain could be attributed to a higher precision of spike timing. In a third-order neuron, a rise in temperature affected the interactions of inhibition and excitation in a complex manner, also resulting in a better resolution of gaps in the millisecond range. 相似文献