Dense subspaces of quasinormable spaces

Dense linear subspaces of quasinormable Fréchet spaces need not be quasinormable, as an example due to J. Bonet and S. Dierolf proved. A characterization of the quasinormability of dense linear subspaces of quasinormable locally convex spaces and several consequences are given. Moreover, an example of a dense linear subspace of a countable direct sum of Banach spaces, which is not quasinormable, is provided. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Effect of the structure of latex particles on adhesion. Part I: Synthesis and characterization of structured latex particles of acrylic copolymers and their peel adhesion behavior

This is a series of articles that deals with fundamental aspects of the effects of the structure of latex particles of acrylic copolymers on their adhesion behavior. Specifically, relationship or analogy between rheological properties and adhesion performance of the acrylic copolymers was demonstrated. The first part of this series concerns the synthesis and characterization of latex particles with desired structures and compositions, and the experimental results of peel adhesion. The second part develops an analogy between the peel adhesion performance of the adhesives and rheological properties of the corresponding copolymers. The third part addresses the generalities and particularities of three major tests for adhesion: peeling, blistering, and spontaneous peeling. Three types of structured latex particles were synthesized by three different emulsion polymerization processes: the first type had a uniform composition over the entire particles with a glass transition temperature (T_g) varying between ?40°C and 0°C, depending upon the compositions of monomers involved in the copolymer; the second type was of core-shell structure. As for the third type, the composition of monomers varied gradually across the particle radii. The glass transition behavior and the dynamic mechanical properties in the solid state of the copolymers confirmed the structures of the corresponding latex particles. On the other hand, the peel adhesion performance of the films of these latex particles varied with the dynamic mechanical properties of the corresponding copolymers. This implies that a correlation could be found between the structure of the latex particles, dynamic mechanical properties in the solid state of the corresponding copolymers, and the peel adhesion performance of the adhesive films. ©1995 John Wiley & Sons, Inc.     

Motion, deformation and aggregation of two cells in a microchannel by dielectrophoresis

The dynamic behavior of two cells in a microchannel subject to a nonuniform electric field is simulated numerically by a two-fluid model in the present work. Owing to the presence of nonuniform electric field, usually the cells are polarized and then the dielectrophoresis occurs. The dielectrophoretic force induces the movement and deformation of cells in the microchannel. Meanwhile, the cell membrane develops a mechanical force to resist the cell deformation. In addition, the intercellular interaction becomes dominant when the cell-cell distance is short enough such that an intercellular force is generated. The three forces are taken into account in the two-fluid model to characterize the dynamic behavior of cells. In order to validate the present model, the cell deformation is calculated and compared with the experimental results published previously, where a quantitative agreement is achieved. It is demonstrated by simulations that the cell conductivity mainly determines the motion and deformation of cells at low frequency. Instead of the cell conductivity however, the cell permittivity plays a critical and leading role at high frequency. These phenomena are consistent with the experimental observations. Furthermore, the intercellular interaction may cause the change in the dynamic behavior of cells.     

Ternary cobalt-iron phosphide nanocrystals with controlled compositions, properties, and morphologies from nanorods and nanorice to split nanostructures

Structural phase-controlled formation of binary Co(2)P and CoP nanocrystals is achieved by reacting cobalt(II) oleate with trioctylphosphine. In the absence of oleylamine, Co(2)P nanowires are formed at both 290 and 320 °C. In the presence of oleylamine, Co(2)P nanorods are formed at 290 °C, and CoP nanorods are formed at 320 °C. With the simultaneous reaction of iron(III) oleate and cobalt(II) oleate with trioctylphosphine in the presence of oleylamine, ternary Co(2)P-type cobalt-iron phosphide nanostructures are produced at both 290 and 320 °C, corresponding to rice-shaped Co(1.5)Fe(0.5)P nanorods and split Co(1.7)Fe(0.3)P nanostructures, respectively. The controlled incorporation of iron into cobalt phosphide can alter the magnetic properties from paramagnetic binary Co(2)P to ferromagnetic Co(2)P-type ternary cobalt-iron phosphide nanostructures. Meanwhile, the time-dependent morphological evolution from small nanodots/nanorods, through seeded growth to unique split nanostructures is demonstrated in one-pot reaction at 320 °C.     

Antifeedant activity of long-chain alcohols,and fungal and plant metabolites against pea aphid (Acyrthosiphon pisum) as potential biocontrol strategy

Aphids are noxious insect pests of major crops including cereals and legumes. Particularly, pea aphid (Acyrthosiphon pisum) causes significant yield and quality loses in pea. Crop protection is largely based on noxious chemical pesticides which have prompted a renewed interest in the discovery of natural products as alternatives to synthetic insecticides. In this study different classes of natural compounds were tested in dual choice bioassays to evaluate their feeding deterrence and mortality effect on pea aphid. High feeding deterrence was produced by some of the compounds, particularly1-hexadecanol, gliotoxin, cyclopaldic acid and seiridin. On the contrary, aphid mortality was low although significant for 1-heptadecanol, cytochalasin A, 1-nonadecanol and gliotoxin. Phytotoxicity assessment showed low or imperceptible plant damaged for cytochalasin A, seiridin and 1-nonadecanol. The results obtained showed the potential of seiridin to be used as an alternative to synthetic insecticides.     

Interaction of polysaccharide-protein complex from Agaricus blazei with Langmuir and Langmuir-Blodgett films of phospholipids

The use of natural substances in health applications may be hampered by the difficulties in establishing the mechanisms of action, especially at molecular-level. The protein-polysaccharide complex extracted from the mushroom Agaricus blazei Murill, referred to as CAb, has been considered for treating various diseases with probable interaction with cell membranes. In this study, we investigate the interaction between CAb and a cell membrane model represented by a Langmuir monolayer of dimyristoyl phosphatidic acid (DMPA). CAb affects the structural properties of DMPA monolayers causing expansion and increasing compressibility. In addition, interaction with DMPA polar heads led to neutralization of the electrical double layer, yielding a zero surface potential at large areas per molecule. CAb remained at the interface even at high surface pressures, which allowed transfer of Langmuir-Blodgett (LB) films onto solid supports with the CAb-DMPA mixture. The mass transferred, according to quartz crystal microbalance (QCM) measurements, increased linearly with the number of deposited layers. With UV-vis absorption, fluorescence and FTIR spectroscopies, we confirmed that the LB films contain polysaccharides, proteins and DMPA. Therefore, the CAb biological action must be attributed not only to polysaccharides but also to proteins in the complex.     

Kaonic nuclear systems KN and KNN as decaying states

The formation spectra of model KN and KNN systems formed by (K(-),n) reactions are investigated in order to obtain a theoretical basis for a proper interpretation of experimental data concerning kaonic nuclear quasi-bound states. It has been clarified that the experimentally observable kaonic nuclear state K(-)pp should be regarded as the decaying state introduced by Kapur-Peierls, which is different from the pole state solution of the Faddeev equation.     

A note on the calculations of spin–spin coupling constants involving carbon

Sum-over-states perturbation and self-consistent perturbation calculations of ⁿJ(CC) using standard INDO parameters are discussed. Calculated values of ¹J(OC) for acetone are reported. In general it seems that the sum-over-states calculations are the more reliable. The importance of including non-contact contributions in the calculation of couplings between carbon and nuclei with larger values of 〈r^?3〉 is stressed.     

Physicochemical characterization of a new raw material obtained from leaves of <Emphasis Type="Italic">Syzygium cumini</Emphasis> (L.) Skeel (Myrtaceae)

The aim of this study was to determine the physicochemical characteristics of leaves of Syzygium cumini L. Skeels plant and characterize the extract of this plant by analytical techniques. Pharmacopeial methods of physicochemical analysis were used, including morphological characterization of the particle, thermal analysis, infrared spectroscopy and X-ray diffraction. The plant drug was presented as a coarse powder, within the appropriate Brazilian Pharmacopoeia parameters. The X-ray diffraction, optical microscopy and scanning electron microscopy suggested that the extract particles are amorphous and have irregular shapes, so that clusters of different sizes and morphologies are displayed. Thermal decomposition of the organic components in the sample started in a step that occurred between 151.64 and 209.27 °C with mass loss of 9.08 %, followed by another step with more significant mass loss (28.16 %). The infrared spectrum, in turn, showed many functional groups of compounds present in the lyophilized extract in different absorption bands. The results showed that the analytical techniques allowed us to characterize the physicochemical properties of the plant leaves, which may be useful in the production of new herbal medicines.     

Dipterocarpus tuberculatus Roxb. Ethanol Extract Has Anti-Inflammatory and Hepatoprotective Effects In Vitro and In Vivo by Targeting the IRAK1/AP-1 Pathway

Dipterocarpus tuberculatus Roxb. has been used traditionally as a remedy for many diseases, especially inflammation. Therefore, we analyzed and explored the mechanism of the anti-inflammatory effect of a Dipterocarpus tuberculatus Roxb. ethanol extract (Dt-EE). Dt-EE clearly and dose-dependently inhibited the expression of pro-inflammatory cytokines such as IL-6, TNF-α, and IL-1β in lipopolysaccharide (LPS)-treated RAW264.7 cells. Also, Dt-EE suppressed the activation of the MyD88/TRIF-mediated AP-1 pathway and the AP-1 pathway related proteins JNK2, MKK4/7, and TAK1, which occurred as a result of inhibiting the kinase activity of IRAK1 and IRAK4, the most upstream factors of the AP-1 pathway. Finally, Dt-EE displayed hepatoprotective activity in a mouse model of hepatitis induced with LPS/D-galactosamine (D-GalN) through decreasing the serum levels of alanine aminotransferase and suppressing the activation of JNK and IRAK1. Therefore, our results strongly suggest that Dt-EE could be a candidate anti-inflammatory herbal medicine with IRAK1/AP-1 inhibitory and hepatoprotective properties.