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81.
Frequencies of rotational transitions of XeH+ and its isotopic species were measured in the 1–5 THz region with a highprecision far-infrared spectrometer using a tunable radiation source. Measured frequencies were analyzed together with previous microwave and infrared measurements to refine mass-independent Dunham parameters.  相似文献   
82.
This paper describes a methodology for evaluation of influence of microscopic uncertainty in material properties and geometry of a microstructure on a homogenized macroscopic elastic property of an inhomogeneous material. For the analysis of the stochastic characteristics of a homogenized elastic property, the first-order perturbation method is used. In order to analyze the influence of microscopic geometrical uncertainty, the perturbation-based equivalent inclusion method is formulated. In this paper, an analytical form of the perturbation term using the equivalent inclusion method is provided.As a numerical example, macroscopic stochastic characteristics such as an expected value or variance of the homogenized elastic tensor of a unidirectional fiber reinforced plastic, which is caused by microscopic uncertainty in material properties or geometry of a microstructure, are estimated with computing the first order perturbation term of the homogenized elastic tensor. Compared the results of the proposed method with the results of the Monte-Carlo simulation, validity, effectiveness and a limitation of the perturbation-based homogenization method is investigated.  相似文献   
83.
The ability to monitor proteolytic pathways that remove unwanted and damaged proteins from cells is essential for understanding the multiple processes used to maintain cellular homeostasis. In this study, we have developed a new protein-labeling probe that employs an ‘OFF–ON–OFF’ fluorescence switch to enable real-time imaging of the expression (fluorescence ON) and degradation (fluorescence OFF) of PYP-tagged protein constructs in living cells. Fluorescence switching is modulated by intramolecular contact quenching interactions in the unbound probe (fluorescence OFF) being disrupted upon binding to the PYP-tag protein, which turns fluorescence ON. Quenching is then restored when the PYP-tag–probe complex undergoes proteolytic degradation, which results in fluorescence being turned OFF. Optimization of probe structures and PYP-tag mutants has enabled this fast reacting ‘OFF–ON–OFF’ probe to be used to fluorescently image the expression and degradation of short-lived proteins.

An “OFF–ON–OFF” fluorescence probe for real-time imaging of the expression (fluorescence ‘OFF’) and degradation (fluorescence ‘ON’) of short lived PYP-tag proteins in cellular systems.  相似文献   
84.
Recently, there has been a strong demand for technologies that use hydrogen as an energy carrier, instead of fossil fuels. Hence, new and effective hydrogen storage technologies are attracting increasing attention. Formic acid (FA) is considered an effective liquid chemical for hydrogen storage because it is easier to handle than solid or gaseous materials. This review presents recent advances in research into the development of homogeneous catalysts, primarily focusing on hydrogen generation by FA dehydrogenation. Notably, this review will aid in the development of useful catalysts, thereby accelerating the transition to a hydrogen-based society.  相似文献   
85.
Anemia is a major complication of chronic renal failure. To treat this anemia, prolylhydroxylase domain enzyme (PHD) inhibitors as well as erythropoiesis-stimulating agents (ESAs) have been used. Although PHD inhibitors rapidly stimulate erythropoietin (Epo) production, the precise sites of Epo production following the administration of these drugs have not been identified. We developed a novel method for the detection of the Epo protein that employs deglycosylation-coupled Western blotting. With protein deglycosylation, tissue Epo contents can be quantified over an extremely wide range. Using this method, we examined the effects of the PHD inhibitor, Roxadustat (ROX), and severe hypoxia on Epo production in various tissues in rats. We observed that ROX increased Epo mRNA expression in both the kidneys and liver. However, Epo protein was detected in the kidneys but not in the liver. Epo protein was also detected in the salivary glands, spleen, epididymis and ovaries. However, both PHD inhibitors (ROX) and severe hypoxia increased the Epo protein abundance only in the kidneys. These data show that, while Epo is produced in many tissues, PHD inhibitors as well as severe hypoxia regulate Epo production only in the kidneys.  相似文献   
86.
The transport and trafficking of metabolites are critical for the correct functioning of live cells. However, in situ metabolic imaging studies are hampered by the lack of fluorescent chemical structures that allow direct monitoring of small metabolites under physiological conditions with high spatial and temporal resolution. Herein, we describe SCOTfluors as novel small‐sized multi‐colored fluorophores for real‐time tracking of essential metabolites in live cells and in vivo and for the acquisition of metabolic profiles from human cancer cells of variable origin.  相似文献   
87.
Transition metal dichalcogenides (TMDCs) have received attention as atomically thin post-silicon semiconducting materials. Tuning the carrier concentrations of the TMDCs is important, but their thin structure requires a non-destructive modulation method. Recently, a surface-charge transfer doping method was developed based on contacting molecules on TMDCs, and the method succeeded in achieving a large modulation of the electronic structures. The successful dopant is a neutral benzyl viologen (BV0); however, the problem remains of how to effectively prepare the BV0 molecules. A reduction process with NaBH4 in water has been proposed as a preparation method, but the NaBH4 simultaneously reacts vigorously with the water. Here, a simple method is developed, in which the reaction vial is placed on a hotplate and a fragment of air-stable metal is used instead of NaBH4 to prepare the BV0 dopant molecules. The prepared BV0 molecules show a strong doping ability in terms of achieving a degenerate situation of a TMDC, MoS2. A key finding in this preparation method is that a convection flow in the vial effectively transports the produced BV0 to a collection solvent. This method is simple and safe and facilitates the tuning of the optoelectronic properties of nanomaterials by the easily-handled dopant molecules.  相似文献   
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