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151.
152.
The bioanode is the defining feature of microbial fuel cell (MFC) technology and often limits its performance. In the current work, we report the engineering of a novel hierarchically porous architecture as an efficient bioanode, consisting of biocompatible chitosan and vacuum-stripped graphene (CHI/VSG). With the hierarchical pores and unique VSG, an optimized bioanode delivered a remarkable maximum power density of 1530 mW m(-2) in a mediator-less MFC, 78 times higher than a carbon cloth anode. 相似文献
153.
Yingying Zhang Shuang Wang Lu Wang Xiaoyan Chang Yongxiao Fan Meiqing He Dawei Yan 《International journal of molecular sciences》2022,23(10)
Plasmodesmata (PD) are plant-specific channels connecting adjacent cells to mediate intercellular communication of molecules essential for plant development and defense. The typical PD are organized by the close apposition of the plasma membrane (PM), the desmotubule derived from the endoplasmic reticulum (ER), and spoke-like elements linking the two membranes. The plasmodesmal PM (PD-PM) is characterized by the formation of unique microdomains enriched with sphingolipids, sterols, and specific proteins, identified by lipidomics and proteomics. These components modulate PD to adapt to the dynamic changes of developmental processes and environmental stimuli. In this review, we focus on highlighting the functions of sphingolipid species in plasmodesmata, including membrane microdomain organization, architecture transformation, callose deposition and permeability control, and signaling regulation. We also briefly discuss the difference between sphingolipids and sterols, and we propose potential unresolved questions that are of help for further understanding the correspondence between plasmodesmal structure and function. 相似文献
154.
Young-Hyun Baek Jin-Ho Lee Sang-Jin Chang Yuri Chae Myung-Hun Lee Sun-Hong Kim Kwon-Il Han Tack-Joong Kim 《International journal of molecular sciences》2022,23(10)
Minoxidil is the most widely used treatment for hair growth, but has been associated with several side effects. In this study, we investigated the effects of heat-killed Enterococcus faecalis EF-2001 on hair loss prevention and regrowth using human dermal papilla cells and male C57BL/6 mice. To examine the effects of EF-2001, we used minoxidil as the positive control. In the in vitro experiments, EF-2001 treatment (75–500 μg/mL) led to the proliferation of human dermal papilla cells in a concentration-dependent manner. In the in vivo experiment, the topical application of 200 µL EF-2001 on the dorsal surface of C57BL/6 male mice led to hair growth. Changes in hair regrowth were examined by visual comparison and hematoxylin and eosin staining of skin sections. We also determined the expression levels of marker genes (Wnt) and growth factors (fibroblast growth factor, insulin growth factor 1, and vascular endothelial growth factor) in the skin tissues of the back of each mouse using a quantitative polymerase chain reaction. EF-2001 accelerated the progression of hair regrowth in mice and promoted hair-follicle conversion from telogen to anagen, likely by increasing the expression levels of growth factors and marker genes. 相似文献
155.
156.
Han F Wang Y Sims CE Bachman M Chang R Li GP Allbritton NL 《Analytical chemistry》2003,75(15):3688-3696
In the past decade, capillary electrophoresis has demonstrated increasing utility for the quantitative analysis of single cells. New applications for the analysis of dynamic cellular properties demand sampling methods with sufficient temporal resolution to accurately measure these processes. In particular, intracellular signaling pathways involving many enzymes can be modulated on subsecond time scales. We have developed a technique to rapidly lyse an adherent mammalian cell using a single electrical pulse followed by efficient loading of the cellular contents into a capillary. Microfabricated electrodes were designed to create a maximum voltage drop across the flattened cell's plasma membrane at a minimum interelectrode voltage. The influence of the interelectrode distance, pulse duration, and pulse strength on the rate of cell lysis was determined. The ability to rapidly lyse a cell and collect and separate the cellular contents was demonstrated by loading cells with Oregon Green and two isomers of carboxyfluorescein. All three fluorophores were detected with a separation efficiency comparable to that of standards. Parallel comparison of electrical lysis to that produced by a laser-based lysis system revealed that the sampling efficiencies of the two techniques were comparable. Rapid cell lysis by an electrical pulse may increase the application of capillary electrophoresis to the study of cellular dynamics requiring fast sampling times. 相似文献
157.
Artificial Protection Film on Lithium Metal Anode toward Long‐Cycle‐Life Lithium‐Oxygen Batteries 下载免费PDF全文
158.
159.
A symbolic procedure is utilized to derive the analytical expressions of the component matrices resulting to the closed-form integration of a stiffness matrix of a hybrid finite element. In order to alleviate the expression growth problem, we employ special techniques, including the use of symmetry conditions, pattern search, and introduction of intermediate variables, so that the final form of the derived stiffness matrix is suitable for coding implementation. Application of the symbolic procedure is made on a hybrid three-dimensional 8-node solid element. The same procedure is equally applicable to other types of hybrid elements. 相似文献
160.
现有基于软件体系结构的可靠性模型只适用于符合马尔可夫过程的软件构件转移关系,而当构件间存在由确定性和随机性转移关系组成的异构结构时,仍按照马尔可夫过程对软件体系结构建模,会导致可靠性评估结果不准确。为了解决现有模型不适用于异构结构的问题,在分析构件转移关系基础上,提出了一个新的软件可靠性模型。基于软件UML顺序图,提出将异构软件结构转换为马尔可夫链的算法。通过对一个实例的可靠性评估,验证了新模型能够比现有模型获得更准确的评估结果。 相似文献