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81.
82.
Beatriz A. Rodas-Junco Graciela E. Racagni-Di-Palma Michel Canul-Chan Javier Usorach S. M. Teresa Hernndez-Sotomayor 《International journal of molecular sciences》2021,22(5)
Plants are subject to different types of stress, which consequently affect their growth and development. They have developed mechanisms for recognizing and processing an extracellular signal. Second messengers are transient molecules that modulate the physiological responses in plant cells under stress conditions. In this sense, it has been shown in various plant models that membrane lipids are substrates for the generation of second lipid messengers such as phosphoinositide, phosphatidic acid, sphingolipids, and lysophospholipids. In recent years, research on lipid second messengers has been moving toward using genetic and molecular approaches to reveal the molecular setting in which these molecules act in response to osmotic stress. In this sense, these studies have established that second messengers can transiently recruit target proteins to the membrane and, therefore, affect protein conformation, activity, and gene expression. This review summarizes recent advances in responses related to the link between lipid second messengers and osmotic stress in plant cells. 相似文献
83.
Delfino Chamorro-Arenas Giovanna Salgado-Moreno Dr. Liliana Martinez-Mendieta Dr. Leticia Quintero Dr. Beatriz Godínez-Chaparro Prof. Fernando Sartillo-Piscil 《ChemMedChem》2021,16(3):472-476
The design, stereoselective synthesis and in vivo antiallodynic activity of four novel paroxetine analogs, named 3-hydroxy paroxetines (3HPXs), is reported herein. Among the novel synthesized compounds, three showed an antiallodynic effect, while (R,R)-3HPX was found to be 2.5 times more bioactive than (-)-paroxetine itself in neuropathic rats. Consequently, the current investigation not only discloses a novel promising analgesic drug, but also reveals that functionalization at the C3 position of paroxetine could be as effective as the common functionalization at either C4 or within the sesamol group. 相似文献
84.
85.
Patricia Muñoz-Escalona Shreyes Melkote Kai Liu 《Journal of Materials Engineering and Performance》2005,14(5):582-590
In recent years, the finite element method (FEM) has become the main tool for simulating the metal cutting process because
research based on trial and error is time consuming and requires high investment. Early studies were done by different investigators.
In this research AISI 52100, hardened steel (62 HRC) was selected for an orthogonal machining process as well as metal cutting
simulation using the software DEFORM-2D. This software is based on a forging process and has been adapted to an orthogonal
machining process. The results of simulated cutting forces were compared with experimental cutting force data to validate
the orthogonal cut simulation. Also, the surface roughness was measured, and the influence of the stress, strain, and temperature
on the surface roughness was studied. 相似文献
86.
E. I. Basaldella J.C. Tara G. Aguilar Armenta M. E. Patiño Iglesias 《Journal of Porous Materials》2007,14(3):273-278
Samples of mesoporous silica SBA-15 were prepared under hydrothermal conditions where Cu cations were incorporated to the
structure by impregnation in order to compare the adsorption behavior in the presence and absence of this element. The adsorption/desorption
equilibrium isotherms of propylene, propane, and N2 were measured to evaluate their usefulness in the propane/propylene separation.
All the adsorption isotherms of SBA-15 measured in the absence of Cu cations were described by the Freundlich equation, while
the adsorption isotherms of propane on Cu/SBA-15 were better represented by the Henry equation and those of propylene were
satisfactorily described by the Langmuir model in the range P < 100 Torr. The adsorption uptake of propylene increased and that of propane decreased in Cu/SBA-15 as compared to the amounts
observed in the SBA-15 sample. The presence of Cu atoms in the adsorbent lattice increased the selectivity towards propylene.
Under some working conditions the adsorbed amount of propylene in Cu/SBA-15 sample was totally reversible and the propane
uptake, negligible. 相似文献
87.
Summary Copolymeric poly(acrylic acid-co-methyl methacrylate) hydrogels for three different compositions: (90/10), (80/20) and (60/40),
have been studied. Drug release has been examined as a function of the hydrogel composition by HPLC (High Pressure Liquid
Cromatography). The release experiments were carried out at 37 °C. The fraction of available drug release was linear in t1/2. The values of the diffusional coefficient (0.50<n<1.0) indicate that the nafcillin release mechanism from the hydrogels
in study is non-Fickian. The diffusion coefficients for this drug release have been calculated. The molecular diffusion of
nafcillin through hydrogels is controlled by the swelling. 相似文献
88.
A series of semi-interpenetrating polymer networks (semi-IPN's) based on different compositions of an acyclic polyethylene terephthalate oligomer and unsaturated polyester resin (UP) were prepared. The oligomer was dissolved in the resin containing styrene crosslinker. Later this mixture was crosslinked at room temperature using methyl ethyl ketone peroxide catalyst and cobalt naphtanate as promoter. The tensile strength of the IPN's decreases as the concentration of oligomer increases, whereas, elongation to break increases. A characterization of the oligomer used is also presented. 相似文献
89.
M Villarroel E Biolley R Schneeberger D Ballester S Santibá?ez 《Archivos latinoamericanos de nutrición》1989,39(2):200-211
The results of the chemical composition and biological quality of deffated hazel nut flour are shown. The samples analyzed contained significant amounts of proteins (19%) comparable to legume flour, higher than cereals and lower than deffated oleaginous flours. The oil extracted from the seed was analyzed and the average results obtained were the following: Refraction index, 1.47; saponification No. 184.8; iodine No. 85.0. The average composition of the fatty acids obtained by gas liquid chromatography was: Palmitic acid 2.3% Palmitoleic acid 37.0% Stearic acid 0.5% Oleic acid 39.5% Linoleic acid 6.9% Linolenic acid 1.1% Eicosanoic acid 2.3% Eicosaenoic acid 4.6% Docosenoic acid 3.4% Tetraeicosanoic acid 0.3% These results indicate a good-quality oil due to the low content of linolenic acid. The nutritive value of the deffated meal measured in the rats gave a net protein ratio (NPR) of 3.58, lower than the corresponding casein value (4.10). The true protein digestibility measured in the rat gave a value of 7.3%, compared to 95% for casein. The amounts of iron and phosphorous are comparatively lower than those reported for rape-seed meal and sunflower meal. 相似文献
90.
In this paper, an asymptotic expansion is constructed to solve second-order differential equation systems with highly oscillatory forcing terms involving multiple frequencies. An asymptotic expansion is derived in inverse of powers of the oscillatory parameter and its truncation results in a very effective method of dicretizing the differential equation system in question. Numerical experiments illustrate the effectiveness of the asymptotic method in contrast to the standard Runge–Kutta method. 相似文献