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Electrospray mass spectrometry/mass spectrometry was used to investigate the gas‐phase properties of protonated expanded porphyrins, in order to correlate those with their structure and conformation. We have selected five expanded meso‐pentafluorophenyl porphyrins, respectively, a pair of oxidized/reduced fused pentaphyrins (22 and 24 π electrons), a pair of oxidized/reduced regular hexaphyrins (26 and 28 π electrons) and a regular doubly N‐fused hexaphyrin (28 π electrons). The gas‐phase behavior of the protonated species of oxidized and reduced expanded porphyrins is different. The oxidized species (aromatic Hückel systems) fragment more extensively, mainly by the loss of two HF molecules. The reduced species (Möbius aromatic or Möbius‐like aromatic systems) fragment less than their oxidized counterparts because of their increased flexibility. The protonated regular doubly fused hexaphyrin (non‐aromatic Hückel system) shows the least fragmentation even at higher collision energies. In general, cyclization through losses of HF molecules decreases from the aromatic Hückel systems to Möbius aromatic or Möbius‐like aromatic systems to non‐aromatic Hückel systems and is related to an increase in conformational distortion. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
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The way cells communicate is not fully understood. However, it is well-known that extracellular vesicles (EVs) are involved. Researchers initially thought that EVs were used by cells to remove cellular waste. It is now clear that EVs function as signaling molecules released by cells to communicate with one another, carrying a cargo representing the mother cell. Furthermore, these EVs can be found in all biological fluids, making them the perfect non-invasive diagnostic tool, as their cargo causes functional changes in the cells upon receiving, unlike synthetic drug carriers. EVs last longer in circulation and instigate minor immune responses, making them the perfect drug carrier. This review sheds light on the latest development in EVs isolation, characterization and, application as therapeutic cargo, novel drug loading techniques, and diagnostic tools. We also address the advancement in plant-derived EVs, their characteristics, and applications; since plant-derived EVs only recently gained focus, we listed the latest findings. Although there is much more to learn about, EV is a wide field of research; what scientists have discovered so far is fascinating. This paper is suitable for those new to the field seeking to understand EVs and those already familiar with it but wanting to review the latest findings.  相似文献   
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S B Rosalki  A Y Foo 《Electrophoresis》1989,10(8-9):604-611
An affinity electrophoresis procedure is described for the separation and quantification of the bone- and liver-derived fractions of alkaline phosphatase in plasma. Separation is carried out on cellulose acetate membrane pre-soaked with buffer containing wheat germ lectin. The electrophoretic mobility of the bone enzyme is preferentially retarded by the lectin and this fraction is well separated from the liver fraction. After separation, enzyme activity is demonstrated by staining using an indigogenic alkaline phosphatase substrate incorporated in agar gel, and the stained fractions quantified by densitometry. The procedure has low imprecision, good linearity, and the activities of the bone and liver fractions correlate well with values obtained using nonelectrophoretic quantification methods. The procedure is especially suitable for use in the diagnostic laboratory.  相似文献   
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High reliance on crude oil for energy consumption results in the urgent need to explore and develop alternative renewable sources. One of the most promising routes is the transformation of biomass into biofuels and chemicals. The introduction of deep eutectic solvents in 2004 received a considerable amount of attention across different research fields, particularly in biomass processing. The effectiveness of deep eutectic solvents in breaking down the recalcitrant structure in biomass highlights its impact on the transformation of biomass into various value-added products. In addition, deep eutectic solvents are widely regarded as promising “green” solvents due to their low cost, low toxicity, and biodegradable properties. In this paper, some background information on lignocellulosic biomass and deep eutectic solvents is given. Furthermore, the roles of deep eutectic solvents in biomass processing are discussed, focusing on the impacts of deep eutectic solvents on the selectivity of chemical processes and dissolution of biomass. This review also highlights the advantages and limitations of deep eutectic solvents associated with their usage in biomass valorization.  相似文献   
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A case study was conducted on an experienced upper extremity prosthetic user that required him to perform a reaching and grasping task with both his prosthetic and normal anatomical hand. We used a scanning task (Wallace, Stevenson, Spear, & Weeks, 1994; Button, Bennett, & Davids, 1998) that required the participant to perform a wide range of coordination patterns defined by the relative phasing between the aperture of the fingers (or artificial prehensor) and the arm. Visual templates of the required finger trajectories in the various required phase conditions served as environmental information for the subject to follow. Based on previous work, we hypothesized that the participant would exhibit at least one stable reaching and grasping pattern in both his anatomical and prosthetic arm. In support of this hypothesis, the results showed a negative sloping relationship between the required relative phase and the mean delta relative phase (required relative phase minus the actual relative phase). The smallest delta relative phase occurred at approximately 80° and 115° relative phase for the anatomical and prosthetic arm, respectively during the scanning task. These results confirm our previous work of the presence of only one attractor in reaching and grasping movements using either the anatomical or prosthetic arm.  相似文献   
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Water scarcity and pollution rank equal to climate change as the most urgent environmental turmoil for the 21st century. To date, the percolation of textile effluents into the waterways and aquifer systems, remain an intricate conundrum abroad the nations. With the renaissance of activated carbon, there has been a steadily growing interest in the research field. Recently, the adoption of titanium dioxide, a prestigious advanced photo-catalyst which formulates the new growing branch of activated carbon composites for enhancement of adsorption rate and discoloration capacity, has attracted stern consideration and supports worldwide. Confirming the assertion, this paper presents a state of art review of titanium dioxide/activated carbon composites technology, its fundamental background studies, and environmental implications. Moreover, its major challenges together with the future expectation are summarized and discussed. Conclusively, the expanding of activated carbons composites material represents a potentially viable and powerful tool, leading to the plausible improvement of environmental conservation.  相似文献   
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The ligand CH2(P(o-C6H4NMe2)2)2 (dmapm) gives access to the first example of a dipalladium(I) complex supported by a tetradentate ligand, Pd2Cl2(mu-N,P,P,N-dmapm), which, unlike the well-known Pd2X2(mu-dppm)2 complexes (X = halide, dppm = bis(diphenylphosphino)methane), reacts with thiols to give addition of RS-H across a phosphine-bridged Pd-Pd bond.  相似文献   
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