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991.
Justin Holmer 《偏微分方程通讯》2013,38(8):1151-1190
We prove local well-posedness of the initial-boundary value problem for the Korteweg–de Vries equation on right half-line, left half-line, and line segment, in the low regularity setting. This is accomplished by introducing an analytic family of boundary forcing operators. 相似文献
992.
In this article, we use edge weighting functions on dominating sets to show that if we impose a regularity condition on a graph, then upper bounds on both the upper domination number and the upper total domination number can be greatly improved. More precisely, we prove that for if G is a k‐regular graph on n vertices, then the upper domination number of G is at most , and the upper total domination number of G is at most . Furthermore, we show that these bounds are sharp and characterize the infinite families of graphs that achieve equality in both these bounds. 相似文献
993.
Many real-life problems are over-constrained, so that no solution satisfying all their constraints exists. Soft constraints, with costs denoting how much the constraints are violated, are used to solve these problems. We use the edit-distance based SoftRegular constraint as an example to show that a propagation algorithm that sometimes underestimates the cost may guide the search to incorrect (non-optimal) solutions to an over-constrained problem. To compute correctly the cost for the edit-distance based SoftRegular constraint, we present a quadratic-time propagation algorithm based on dynamic programming and a proof of its correctness. We also give an improved propagation algorithm using an idea of computing the edit distance between two strings, which may also be applied to other constraints with propagators based on dynamic programming. The asymptotic time complexity of our improved propagator is always at least as good as the one of our quadratic-time propagator, but significantly better when the edit distance is small. Our propagators achieve domain consistency on the problem variables and bounds consistency on the cost variable. Our method can also be adapted for the violation measure of the edit-distance based Regular constraint for constraint-based local search. 相似文献
994.
Nonlinear Dynamics - The large deflections of panels in subsonic flow are considered, specifically a fully clamped von Karman plate accounting for both rotational inertia in plate filaments and... 相似文献
995.
996.
Martin Gillard Dr. Justin Weynand Hugues Bonnet Frédérique Loiseau Prof. Anabelle Decottignies Dr. Jérôme Dejeu Prof. Eric Defrancq Prof. Benjamin Elias 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(61):13849-13860
A series of new RuII Schiff base complexes built on the salphen moiety has been prepared. This includes four flexible monometallic RuII compounds and six rigid bimetallic analogues that contain NiII, PdII or PtII cations into the salphen complexation site. Steady state luminescence titrations illustrated the capacity of the compounds to photoprobe G-quadruplex (G4) DNA. Moreover, the vast array of the Schiff base structural changes allowed to extensively assess the influence of the ligand surface, flexibility and charge on the interaction of the compounds with G4 DNA. This was achieved thanks to circular dichroism melting assays and bio-layer interferometry studies that pointed up high affinities along with good selectivities of RuII Schiff base complexes for G4 DNA. In cellulo studies were carried out with the most promising compounds. Cellular uptake with location of the compounds in the nucleus as well as in the nucleolus was observed. Cell viability experiments were performed with U2OS osteosarcoma cells in the dark and under light irradiation which allowed the measurements of IC50 values and photoindexes. They showed the substantial role played by light irradiation in the activity of the drugs in addition to the low cytotoxicity of the molecules in the dark. Altogether, the reported results emphasize the promising properties of RuII Schiff base complexes as a new class of candidates for developing potential G4 DNA targeting diagnostic or therapeutic compounds. 相似文献
997.
Nicholas A. Lundquist Alfrets D. Tikoalu Dr. Max J. H. Worthington Ryan Shapter Samuel J. Tonkin Dr. Filip Stojcevski Maximilian Mann Dr. Christopher T. Gibson Dr. Jason R. Gascooke Dr. Amir Karton Prof. Dr. Luke C. Henderson Dr. Louisa J. Esdaile Dr. Justin M. Chalker 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(44):10035-10044
Inverse vulcanization provides dynamic and responsive materials made from elemental sulfur and unsaturated cross-linkers. These polymers have been used in a variety of applications such as energy storage, infrared optics, repairable materials, environmental remediation, and precision fertilizers. In spite of these advances, there is a need for methods to recycle and reprocess these polymers. In this study, polymers prepared by inverse vulcanization are shown to undergo reactive compression molding. In this process, the reactive interfaces of sulfur polymers are brought into contact by mechanical compression. Upon heating these molds at relatively low temperatures (≈100 °C), chemical bonding occurs at the polymer interfaces by S−S metathesis. This method of processing is distinct from previous studies on inverse vulcanization because the polymers examined in this study do not form a liquid phase when heated. Neither compression nor heating alone was sufficient to mold these polymers into new architectures, so this is a new concept in the manipulation of sulfur polymers. Additionally, high-level ab initio calculations revealed that the weakest S−S bond in organic polysulfides decreases linearly in strength from a sulfur rank of 2 to 4, but then remains constant at about 100 kJ mol−1 for higher sulfur rank. This is critical information in engineering these polymers for S−S metathesis. Guided by this insight, polymer repair, recycling, and repurposing into new composites was demonstrated. 相似文献
998.
Joshua J. Woods James Lovett Dr. Barry Lai Prof. Hugh H. Harris Prof. Justin J. Wilson 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(16):6544-6553
The mitochondrial calcium uniporter (MCU) is the ion channel that mediates Ca2+ uptake in mitochondria. Inhibitors of the MCU are valuable as potential therapeutic agents and tools to study mitochondrial Ca2+. The best-known inhibitor of the MCU is the ruthenium compound Ru360. Although this compound is effective in permeabilized cells, it does not work in intact biological systems. We have recently reported the synthesis and characterization of Ru265, a complex that selectively inhibits the MCU in intact cells. Here, the physical and biological properties of Ru265 and Ru360 are described in detail. Using atomic absorption spectroscopy and X-ray fluorescence imaging, we show that Ru265 is transported by organic cation transporter 3 (OCT3) and taken up more effectively than Ru360. As an explanation for the poor cell uptake of Ru360, we show that Ru360 is deactivated by biological reductants. These data highlight how structural modifications in metal complexes can have profound effects on their biological activities. 相似文献
999.
The behavior of Ca2AlFeO5 brownmillerite was studied by in situ synchrotron X-ray diffraction and Raman spectroscopy at 300?K with pressures up to 26.5 and 32.1 GPa, respectively. A reversible structural phase transition was observed. The P–V data were fitted by a third-order Birch–Murnaghan equation of state, and the isothermal bulk modulus was obtained as K0?=?181.9(76) GPa with K0′?=?4.4(17). If K0′ was fixed to 4, K0 was obtained as 183.8(20) GPa. Ca2AlFeO5 brownmillerite shows an axial elastic anisotropy since the b-axis is more compressible than a- and c-axis. Combined with previous results, the isothermal bulk modulus and axial compressibility of Ca2AlFeO5 brownmillerite increase with more Al incorporated in the structure. The Raman spectra of Ca2AlFeO5 brownmillerite were analyzed and the pressure coefficients vary from 2.23 to 4.90?cm?1/GPa. The isothermal mode Grüneisen parameters range from 0.83 to 1.77 and the thermal Grüneisen parameter is determined as 1.08(11). 相似文献