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排序方式: 共有321条查询结果,搜索用时 24 毫秒
71.
Triffo SB Huang HH Smith AW Chou ET Groves JT 《Journal of the American Chemical Society》2012,134(26):10833-10842
This study examines the dynamic co-localization of lipid-anchored fluorescent proteins in living cells using pulsed-interleaved excitation fluorescence cross-correlation spectroscopy (PIE-FCCS) and fluorescence lifetime analysis. Specifically, we look at the pairwise co-localization of anchors from lymphocyte cell kinase (LCK: myristoyl, palmitoyl, palmitoyl), RhoA (geranylgeranyl), and K-Ras (farnesyl) proteins in different cell types. In Jurkat cells, a density-dependent increase in cross-correlation among RhoA anchors is observed, while LCK anchors exhibit a more moderate increase and broader distribution. No correlation was detected among K-Ras anchors or between any of the different anchor types studied. Fluorescence lifetime data reveal no significant F?rster resonance energy transfer in any of the data. In COS 7 cells, minimal correlation was detected among LCK or RhoA anchors. Taken together, these observations suggest that some lipid anchors take part in anchor-specific co-clustering with other existing clusters of native proteins and lipids in the membrane. Importantly, these observations do not support a simple interpretation of lipid anchor-mediated organization driven by partitioning based on binary lipid phase separation. 相似文献
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73.
Inverse Jacobi multipliers are a natural generalization of inverse integrating factors ton-dimensional dynamical systems. In this paper, the corresponding theory is developed from its beginning in the formal methods
of integration of ordinary differential equations and the “last multiplier” of K. G. Jacobi. We explore to what extent the
nice properties of the vanishing set of inverse integrating factors are preserved in then -dimensional case. In particular, vanishing on limit cycles (in restricted sense) of an inverse Jacobi multiplier is proved
by resorting to integral invariants. Extensions of known constructions of inverse integrating factors by means of power series,
local Lie Groups and algebraic solutions are provided for inverse Jacobi multipliers as well as a suitable generalization
of the concept to systems with discontinuous right-hand side. 相似文献
74.
Perruchas S Flores S Jousselme B Lobkovsky E Abruña H Disalvo FJ 《Inorganic chemistry》2007,46(21):8976-8987
The functionalization of octahedral [W(6)S(8)] clusters with a family of phosphino-thiophene ligands has been investigated with the goal of synthesizing extended networks of [W(6)S(8)] units covalently linked to one another through thiophene-conjugated bridges. In addition to new phosphino-thiophene ligands, eight clusters were synthesized and characterized by (1)H and (31)P NMR spectroscopies, elemental analysis, and UV-vis absorption. These clusters are formulated [W(6)S(8)(T-PPh(2))6] (1a), [W(6)S(8)(T-PEt(2))(6)] (1b), [W(6)S(8)(2T-PPh(2))(6)] (2a), [W(6)S(8)(2T-PEt(2))(6)] (2b), [W(6)S(8)(3T-PPh(2))(6)] (3a), [W(6)S(8)(3T-PEt(2))(6)] (3b), [W(6)S(8)((2T)(3)P)(6)] (4), and [W(6)S(8)(2EDOT-PEt(2))(6)] (5) (T = thiophene and EDOT = 3,4-ethylenedioxythiophene). The molecular structure of six of them has been obtained by single-crystal X-ray diffraction analysis. All of them crystallize in the P1 triclinic space group except 3b, which has the P2(1)/c monoclinic symmetry. The redox behavior of both the ligands and the corresponding functionalized clusters has been investigated by cyclic voltammetry. An attempt to electropolymerize these species is also reported. 相似文献
75.
Prof. Philip N. Bartlett Jennifer Burt Dr. David A. Cook Dr. Charles Y. Cummings Prof. Michael W. George Prof. Andrew L. Hector Mahboba M. Hasan Dr. Jie Ke Prof. William Levason Dr. David Pugh Prof. Gillian Reid Dr. Peter W. Richardson Prof. David C. Smith Joe Spencer Norhidayah Suleiman Dr. Wenjian Zhang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(1):302-309
For the first time, a versatile electrolyte bath is described that can be used to electrodeposit a wide range of p‐block elements from supercritical difluoromethane (scCH2F2). The bath comprises the tetrabutylammonium chlorometallate complex of the element in an electrolyte of 50×10?3 mol dm?3 tetrabutylammonium chloride at 17.2 MPa and 358 K. Through the use of anionic ([GaCl4]?, [InCl4]?, [GeCl3]?, [SnCl3]?, [SbCl4]?, and [BiCl4]?) and dianionic ([SeCl6]2? and [TeCl6]2?) chlorometallate salts, the deposition of elemental Ga, In, Ge, Sn, Sb, Bi, Se, and Te is demonstrated. In all cases, with the exception of gallium, which is a liquid under the deposition conditions, the resulting deposits are characterised by SEM, energy‐dispersive X‐ray analysis, XRD and Raman spectroscopy. An advantage of this electrolyte system is that the reagents are all crystalline solids, reasonably easy to handle and not highly water or oxygen sensitive. The results presented herein significantly broaden the range of materials accessible by electrodeposition from supercritical fluid and open up the future possibility of utilising the full scope of these unique fluids to electrodeposit functional binary or ternary alloys and compounds of these elements. 相似文献
76.
Jose Portillo-Portillo Gabriel Sanchez-Perez Linda K. Toscano-Medina Aldo Hernandez-Suarez Jesus Olivares-Mercado Hector Perez-Meana Pablo Velarde-Alvarado Ana Lucila Sandoval Orozco Luis Javier García Villalba 《Entropy (Basel, Switzerland)》2022,24(7)
Most of the methods for real-time semantic segmentation do not take into account temporal information when working with video sequences. This is counter-intuitive in real-world scenarios where the main application of such methods is, precisely, being able to process frame sequences as quickly and accurately as possible. In this paper, we address this problem by exploiting the temporal information provided by previous frames of the video stream. Our method leverages a previous input frame as well as the previous output of the network to enhance the prediction accuracy of the current input frame. We develop a module that obtains feature maps rich in change information. Additionally, we incorporate the previous output of the network into all the decoder stages as a way of increasing the attention given to relevant features. Finally, to properly train and evaluate our methods, we introduce CityscapesVid, a dataset specifically designed to benchmark semantic video segmentation networks. Our proposed network, entitled FASSVid improves the mIoU accuracy performance over a standard non-sequential baseline model. Moreover, FASSVid obtains state-of-the-art inference speed and competitive mIoU results compared to other state-of-the-art lightweight networks, with significantly lower number of computations. Specifically, we obtain 71% of mIoU in our CityscapesVid dataset, running at 114.9 FPS on a single NVIDIA GTX 1080Ti and 31 FPS on the NVIDIA Jetson Nano embedded board with images of size and , respectively. 相似文献
77.
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79.
Soltzberg LJ Slinker JD Flores-Torres S Bernards DA Malliaras GG Abruña HD Kim JS Friend RH Kaplan MD Goldberg V 《Journal of the American Chemical Society》2006,128(24):7761-7764
We have used matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry and micro-Raman spectroscopy to identify a quenching species that is formed during operation of [Ru(bpy)3]2+ electroluminescent devices. We identify this performance-degrading product to be the oxo-bridged dimer [(bpy)2(H2O)RuORu(OH2)(bpy)2]4+ and show this dimer to be an effective quencher of device luminescence. This work is the first to detect a specific chemical degradation product formed during iTMC OLED operation. 相似文献
80.
Carlos Alberto Camacho Olguin Arturo Garcia-Borquez Carlos Alberto González-Rodríguez Jose Antonio Loran-Juanico Hector Cruz-Mejía 《辐射效应与固体损伤》2013,168(6):519-527
Diluted alloys of the binary system Ni–Si have been used as target of beam of ions, electrons, neutrons and so on because in this kind of alloy occurs transformations order–disorder, when the temperature is raised. This fact has permitted to evaluate the phenomena associated with the damage induced by irradiation (DII). The results of these works have been employed to understand the behavior under irradiation of complex alloys and to evaluate the reliability of the results of mathematical simulation of the evolution of the DII. The interest in the alloy system Ni-Si has been reborn due to the necessity of developing materials, which have better resistance against the corrosion on more aggressive environments such as those generated on the nuclear power plants or those that exist out of the Earth's atmosphere. Now, a growing interest to use concentrated alloys of this binary system on diverse fields of the materials science has been taking place because up to determined concentration of silicon, a regular eutectic is formed, and this fact opens the possibility to develop lamellar composite material by directional solidification. However, nowadays, there is a lack of fundamental knowledge about the behavior of this type of lamellar structure under aggressive environments, like those mentioned before. Hence, the task of this work is to evaluate the effect that has the irradiation over the microstructure of the concentrated alloy Ni22at%Si. The dendritic region of the hypereutectic alloy consists of an intermetallic phase Ni3Si, whereas the interdendritic region is formed by the alternation of lamellas of solid solution α-Ni and intermetallic phase Ni3Si. Such kind of microstructure has the advantage to get information of the DII over different phases individually, and at the same time, about of the microstructure influence over the global damage in the alloy. The hypereutectic Ni22at%Si alloy was irradiated perpendicularly to its surface, with 3.66?MeV – Ni ions up to 380?dpa at 650°C in a Tandetron linear accelerator. The level of irradiation dose was chosen similar to the irradiation conditions of the next-generation nuclear reactors. The theoretical maximum depth of the DII (maximum depth of damage (MDD)) was calculated as 1.35?µm using the SRIM-2013 program; the laminar microstructure of the eutectic was simulated using the lattice parameters of the eutectic before irradiation. The experimental MDD was 1.47?µm, as determined through transmission electron microscope (TEM) images and the DII was characterized using µX-ray diffraction and TEM. The elimination of cubic phase of the intermetallic Ni3Si, the suppression of lamellae of the α-Ni phase, the generation of dislocation loops and lines, all of these changes generated by the irradiation are clear evidences that the DII was severe. Based on theoretical and experimental evidence, we propose that the amount of phases, alternate of lamellae with different chemical concentrations of silicon and lamellae spatial distribution have a direct relation with the severe evolution of the DII. 相似文献