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The redbay ambrosia beetle, Xyleborus glabratus, is an invasive wood-boring beetle that has become established in the southeastern United States. The beetle transmits the causal pathogen of lethal laurel wilt to susceptible host trees, which include redbay, an important forest community species, and avocado, a valuable food crop. By examining odors of redbay wood, we developed an artificial lure that captured X. glabratus in redbay forests. Eucalyptol was a critical component of the blend for beetle attraction, and eucalyptol alone in large quantities attracted X. glabratus. Furthermore, eucalyptol stimulated boring by X. glabratus into paper arenas. The results suggest that eucalyptol contributes to host selection behavior of X. glabratus and may be useful for management of this pathogen vector.  相似文献   
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Composite hydrogels consisting of nanofibrous bacterial cellulose (BC) embedded in a biocompatible polymeric matrix of various methacrylates were synthesized by UV polymerization using the ‘ever‐wet’ technique. The effect of monomer(s) type and ratio, system dilution at polymerization, monomer(s) hydrophilicity, crosslink density and cellulose/hydrogel ratio was investigated. The effect of BC reinforcement on equilibrium swelling depends on whether the neat gel swells more when brought into contact with water. The major improvement achieved by introduction of 1%–2% BC concerns mechanical properties. Compared with neat gels, the storage shear modulus G′ increased by a factor 10‐20, and the loss part G″ also rose significantly. The compression modulus ranged from 2 to 5.5 MPa for composites swollen to equilibrium (20‐70 wt% water). The BC‐hydrogel composites are considered for application in the tissue engineering area. Copyright © 2012 Society of Chemical Industry  相似文献   
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Calcination of diatomite is an expensive process frequently resulting in products with unpredictable structure. Alternatively, calcination in swirling flow is an energy‐saving option. Computational fluid dynamics modeling of an experimental calcination process unit is presented. Experimental results and systematic collection of process data were used to define boundary condition for steady‐state and transient simulation runs. The comparison of experimental and simulation results shows the complexity of the calcination process. The results can be used for further process optimization.  相似文献   
16.
Structural transitions in materials are accompanied by appreciable and exploitable changes in physical‐chemical properties. Whereas reversible optically‐driven atomistic changes in crystal‐to‐amorphous transitions are generally known and exploited in applications, the nature of the corresponding polyamorphic transitions between two structurally distinct meta‐stable amorphous phases is an unexplored theme. Direct experimental evidence is reported for the nature of the atomistic changes during fully reversible amorphous‐to‐amorphous switching between two individual states in the non‐crystalline As50Se50 films prepared by pulsed‐laser deposition and consequent changes in optical properties. Combination of surface sensitive X‐ray photoelectron spectroscopy and spectroscopic ellipsometry show that the near‐bandgap energy illumination and annealing induce reversible switching in the material's structure by local bonding rearrangements. This is accompanied by switching in refractive index between two well‐defined states. Exploiting the pluralism of distinct structural states in a disordered solid can provide new insights into the data storage in emerging optical memory and photonic applications.  相似文献   
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The irreversible capacity of negative electrode in a lithium-ion cell is a widely described the phenomenon. Irreversible capacity losses are connected with formation of a solid electrolyte interface layer. This layer is growing on the electrode-electrolyte interface during first several charging cycles. The layer is indispensable for proper functioning of a lithium-ion cell. However, during this layer formation, the atoms of lithium are consumed in a range from 18 to 45% of the total amount of lithium atoms presented in cell. Demonstration of possibilities to suppress this phenomenon that occurs on a negative electrode interface is the main aim of this paper.  相似文献   
18.
CI Acid Black 210 was microencapsulated into liposomic systems, and the effects of the microencapsulation on dyebath exhaustion, depth of shade, colour fastness properties and through‐dyeing of chrome‐tanned leather were studied. In comparison with the original dyestuff form, the microencapsulated dye showed a deeper shade and a greater depth of through‐dyeing. Exhaustion and colour fastness values were the same.  相似文献   
19.
Doxorubicin is a commonly used antineoplastic agent in the treatment of many types of cancer. Little is known about the interactions of doxorubicin with cardiac biomolecules. Serious cardiotoxicity including dilated cardiomyopathy often resulting in a fatal congestive heart failure may occur as a consequence of chemotherapy with doxorubicin. The purpose of this study was to determine the effect of exposure to doxorubicin on the changes in major amino acids in tissue of cardiac muscle (proline, taurine, glutamic acid, arginine, aspartic acid, leucine, glycine, valine, alanine, isoleucine, threonine, lysine and serine). An in vitro interaction study was performed as a comparison of amino acid profiles in heart tissue before and after application of doxorubicin. We found that doxorubicin directly influences myocardial amino acid representation even at low concentrations. In addition, we performed an interaction study that resulted in the determination of breaking points for each of analyzed amino acids. Lysine, arginine, β-alanine, valine and serine were determined as the most sensitive amino acids. Additionally we compared amino acid profiles of myocardium before and after exposure to doxorubicin. The amount of amino acids after interaction with doxorubicin was significantly reduced (p = 0.05). This fact points at an ability of doxorubicin to induce changes in quantitative composition of amino acids in myocardium. Moreover, this confirms that the interactions between doxorubicin and amino acids may act as another factor most likely responsible for adverse effects of doxorubicin on myocardium.  相似文献   
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