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111.
A synthetic scheme for the solid-phase synthesis of unprecedented polythioether dendrons has been established, the dendrons prepared up to the fourth generation, and the applicability of the dendronized resins for supported catalysis has been demonstrated. 相似文献
112.
Nitrogen dynamics in the soil under the condition of environmentally friendly fertilization practices (EFFPs) is described by a comprehensive Ndynamics model. The model (first paper of this series, Transport in Porous Media 31(3) (1998), 249–274) is different from other models in its capability of simulating the special phenomena related to the application of EFFPs. In this paper, a finite difference method is used to solve the mathematical model. The numerical model is verified by simulating several water flow and conservative solute transport problems with existing numerical or analytic solutions. The good agreements between our simulation results and the solutions given by others show that our model is reliable in simulating flow and transport problems in the soil. Preliminary model validation is conducted by applying the model to simulate two field experiments. The acceptable agreements between our numerical simulation results and experimental data demonstrate that the model can reasonably model Ndynamics in the soil under field conditions. 相似文献
113.
Kamran Waidha Nikhil Ponnoor Anto Divya Ram Jayaram Avi Golan-Goldhirsh Saravanakumar Rajendran Etta Livneh Jacob Gopas 《Molecules (Basel, Switzerland)》2021,26(9)
Water lily (Nuphar) bioactive extracts have been widely used in traditional medicine owing to their multiple applications against human ailments. Phyto-active Nuphar extracts and their purified and synthetic derivatives have attracted the attention of ethnobotanists and biochemists. Here, we report that 6,6′-dihydroxythiobinupharidine (DTBN), purified from extracts of Nuphar lutea (L.) Sm. leaves, is an effective inhibitor of the kinase activity of members of the protein kinase C (PKC) family using in vitro and in silico approaches. We demonstrate that members of the conventional subfamily of PKCs, PKCα and PKCγ, were more sensitive to DTBN inhibition as compared to novel or atypical PKCs. Molecular docking analysis demonstrated the interaction of DTBN, with the kinase domain of PKCs depicting the best affinity towards conventional PKCs, in accordance with our in vitro kinase activity data. The current study reveals novel targets for DTBN activity, functioning as an inhibitor for PKCs kinase activity. Thus, this and other data indicate that DTBN modulates key cellular signal transduction pathways relevant to disease biology, including cancer. 相似文献
114.
Steinberg Y Schroeder A Talmon Y Schmidt J Khalfin RL Cohen Y Devoisselle JM Begu S Avnir D 《Langmuir : the ACS journal of surfaces and colloids》2007,23(24):12024-12031
Liposomes prepared from a mixture of L-alpha-dipalmitoylphosphatidylcholine and the PEGilated phospholipid N-(carbonylmethoxypoly(ethylene glycol 2000))-1,2-distearoyl-sn-glycero-3-phosphoethanolamine were used as templates for the production of silica and alkylated silica approximately 100 nm capsules, "liposils", entrapping aqueous solutions of anionic dyes. Triggered release of this content was successfully affected by either low-frequency ultrasound or by microwave treatments. Cryo-TEM was used to follow the formation process of these particles, which are aggregated in a chain-like manner. A mechanism explaining this phenomenon is suggested. 相似文献
115.
116.
Cristina Cabrero Dr. Nerea Martín-Pintado Dr. Stefania Mazzini Dr. Raimundo Gargallo Prof. Ramon Eritja Dr. Anna Aviñó Prof. Carlos González 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(26):7351-7355
We report the structural effect of 2'-deoxy-2',2'-difluorocytidine (dFdC) insertions in the DNA strand of a DNA : RNA hybrid duplex and in a self-complementary DNA : DNA duplex. In both cases, the modification slightly destabilizes the duplex and provokes minor local distortions that are more pronounced in the case of the DNA : RNA hybrid. Analysis of the solution structures determined by NMR methods show that dFdC is an adaptable derivative that adopts North type sugar conformation when inserted in pure DNA, or a South sugar conformation in the context of DNA : RNA hybrids. In this latter context, South sugar pucker favors the formation of a 2'F⋅⋅H8 attractive interaction with a neighboring purine, which compensates the destabilizing effect of base pair distortions. These interactions share some features with pseudohydrogen bonds described previously in other nucleic acids structures with fluorine modified sugars. 相似文献
117.
Avi Steiner 《Journal of Pure and Applied Algebra》2019,223(12):5215-5231
Let A be an integer matrix, and assume that its semigroup ring is normal. Fix a face F of the cone of A. We show that the projection and restriction of an A-hypergeometric system to the coordinate subspace corresponding to F are essentially F-hypergeometric; moreover, at most one of them is nonzero.We also show that, if A is in addition homogeneous, the holonomic dual of an A-hypergeometric system is itself A-hypergeometric. This extends a result from [16], proving a conjecture of Nobuki Takayama in the normal homogeneous case. 相似文献
118.
Computational Management Science - This study uses theoretical and empirical approaches to analyze a number of phenomena observed in trading floors, such as the changes in trading volumes and... 相似文献
119.
Karel Cizek Chongdee Thammakhet Kevin Linker Avi Cagan Jeff La Belle 《Analytica chimica acta》2010,661(1):117-744
This article reports on an integrated explosive-preconcentration/electrochemical detection system for 2,4,6-trinitrotoluene (TNT) vapor. The challenges involved in such system integration are discussed. A hydrogel-coated screen-printed electrode is used for the detection of the thermally desorbed TNT from a preconcentration device using rapid square wave voltammetry. Optimization of the preconcentration system for desorption of TNT and subsequent electrochemical detection was conducted yielding a desorption temperature of 120 °C under a flow rate of 500 mL min−1. Such conditions resulted in a characteristic electrochemical signal for TNT representing the multi-step reduction process. Quantitative measurements produced a linear signal dependence on TNT quantity exposed to the preconcentrator from 0.25 to 10 μg. Finally, the integrated device was successfully demonstrated using a sample of solid TNT located upstream of the preconcentrator. 相似文献
120.
Anna Avi?ó Sandra M. Ocampo Clara Caminal José Carlos Perales Ramon Eritja 《Molecular diversity》2009,13(3):287-293
Oligoribonucleotide conjugates carrying nuclear localization peptide sequences at the 3′-end were prepared stepwise on a single
support. The siRNA duplex carrying the nuclear localization peptide sequence at the 3′-end of the passenger strand has similar
inhibitory properties as those of unmodified or cholesterol-modified RNA duplexes. 相似文献