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排序方式: 共有703条查询结果,搜索用时 312 毫秒
91.
Helena Radbruch Daniel Bremer Ronja Mothes Robert Günther Jan Leo Rinnenthal Julian Pohlan Carolin Ulbricht Anja E. Hauser Raluca Niesner 《International journal of molecular sciences》2015,16(5):11713-11727
The development of intravital Förster Resonance Energy Transfer (FRET) is required to probe cellular and tissue function in the natural context: the living organism. Only in this way can biomedicine truly comprehend pathogenesis and develop effective therapeutic strategies. Here we demonstrate and discuss the advantages and pitfalls of two strategies to quantify FRET in vivo—ratiometrically and time-resolved by fluorescence lifetime imaging—and show their concrete application in the context of neuroinflammation in adult mice. 相似文献
92.
Ellis N. ter Horst Nazanin Hakimzadeh Anja M. van der Laan Paul A. J. Krijnen Hans W. M. Niessen Jan J. Piek 《International journal of molecular sciences》2015,16(12):29583-29591
To diminish heart failure development after acute myocardial infarction (AMI), several preclinical studies have focused on influencing the inflammatory processes in the healing response post-AMI. The initial purpose of this healing response is to clear cell debris of the injured cardiac tissue and to eventually resolve inflammation and support scar tissue formation. This is a well-balanced reaction. However, excess inflammation can lead to infarct expansion, adverse ventricular remodeling and thereby propagate heart failure development. Different macrophage subtypes are centrally involved in both the promotion and resolution phase of inflammation. Modulation of macrophage subset polarization has been described to greatly affect the quality and outcome of healing after AMI. Therefore, it is of great interest to reveal the process of macrophage polarization to support the development of therapeutic targets. The current review summarizes (pre)clinical studies that demonstrate essential molecules involved in macrophage polarization that can be modulated and influence cardiac healing after AMI. 相似文献
93.
Máté Szabados Zsófia Csákó Bohumil Kotlík Helena Kazmarová Anna Kozajda Anja Jutraz Andreja Kukec Peter Otorepec Arianna Dongiovanni Andrea Di Maggio Stefano Fraire Tamás Szigeti 《Indoor air》2021,31(4):989-1003
The indoor air quality (IAQ) was investigated in sixty-four primary school buildings in five Central European countries (Czech Republic, Hungary, Italy, Poland, and Slovenia). The concentration of volatile organic compounds, aldehydes, PM2.5 mass, carbon dioxide, radon, as well as physical parameters were investigated during the heating period of 2017/2018. Significant differences were identified for the majority of the investigated IAQ parameters across the countries. The median indoor/outdoor ratios varied considerably. A comprehensive evaluation of IAQ in terms of potential health effects and comfort perception was performed. Hazard quotient values were below the threshold value of 1 with one exception. In contrast, 31% of the school buildings were characterized by hazard index values higher than 1. The maximum cumulative ratio approach highlighted that the concern for non-carcinogenic health effects was either low or the health risk was driven by more substances. The median excess lifetime cancer risk values exceeded the acceptable value of 1 × 10−6 in the case of radon and formaldehyde. PM2.5 mass concentration values exceeded the 24 h and annual guideline values set by the World Health Organization in 56 and 85% of the cases, respectively. About 80% of the schools could not manage to comply with the recommended concentration value for carbon dioxide (1000 ppm). 相似文献
94.
Yihui Zhao Pieter Westerik Rudi Santbergen Erwin Zoethout Han Gardeniers Anja Bieberle‐Hütter 《Advanced functional materials》2020,30(13)
The photoelectrochemical (PEC) activity of microstructured electrodes remains low despite the highly enlarged surface area and enhanced light harvesting. To obtain a deeper understanding of the effect of 3D geometry on the PEC performance, well‐defined WO3/n‐Si and WO3/pn‐Si micropillar arrays are fabricated and subjected to a quantitative analysis of the relationship between the geometry of the micropillars (length, pitch) and their PEC activity. For WO3/n‐Si micropillars, it is found that the photocurrent increases for WO3/n‐Si pillars, but not in proportion to the increase in surface area that results from increased pillar length or reduced pillar pitch. Optical simulations show that a reduced pillar pitch results in areas of low light intensity due to a shadowing effect. For WO3/pn‐Si micropillar photoelectrodes, the p–n junction enhances the photocurrent density up to a factor of 4 at low applied bias potential (0.8 V vs RHE) compared to the WO3/n‐Si. However, the enhancement in photocurrent density increases first and then decreases with reduced pillar pitch, which scales with the photovoltage generated by the p–n junction. This is related to an increased dead layer of the p–n junction Si surface, which results in a decreased photovoltage even though the total surface area increases. 相似文献
95.
96.
Dniel Zmb Anja Schlosser Pascal Rusch Franziska Lübkemann Julian Koch Herbert Pfnür Nadja C. Bigall 《Small (Weinheim an der Bergstrasse, Germany)》2020,16(16)
3D nanoparticle assemblies offer a unique platform to enhance and extend the functionality and optical/electrical properties of individual nanoparticles. Especially, a self‐supported, voluminous, and porous macroscopic material built up from interconnected semiconductor nanoparticles provides new possibilities in the field of sensing, optoelectronics, and photovoltaics. Herein, a method is demonstrated for assembling semiconductor nanoparticle systems containing building blocks possessing different composition, size, shape, and surface ligands. The method is based on the controlled destabilization of the particles triggered by trivalent cations (Y3+, Yb3+, and Al3+). The effect of the cations is investigated via X‐ray photoelectron spectroscopy. The macroscopic, self‐supported aerogels consist of the hyperbranched network of interconnected CdSe/CdS dot‐in‐rods, or CdSe/CdS as well as CdSe/CdTe core‐crown nanoplatelets is used to demonstrate the versatility of the procedure. The non‐oxidative assembly method takes place at room temperature without thermal activation in several hours and preserves the shape and the fluorescence of the building blocks. The assembled nanoparticle network provides longer exciton lifetimes with retained photoluminescence quantum yields, that make these nanostructured materials a perfect platform for novel multifunctional 3D networks in sensing. Various sets of photoelectrochemical measurements on the interconnected semiconductor nanorod structures also reveal the enhanced charge carrier separation. 相似文献
97.
Franziska Lübkemann Jan Frederick Miethe Frank Steinbach Pascal Rusch Anja Schlosser Dniel Zmb Thea Heinemeyer Dominik Natke Dorian Zok Dirk Dorfs Nadja C. Bigall 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(39)
Nanoparticle‐based voluminous 3D networks with low densities are a unique class of materials and are commonly known as aerogels. Due to the high surface‐to‐volume ratio, aerogels and xerogels might be suitable materials for applications in different fields, e.g. photocatalysis, catalysis, or sensing. One major difficulty in the handling of nanoparticle‐based aerogels and xerogels is the defined patterning of these structures on different substrates and surfaces. The automated manufacturing of nanoparticle‐based aerogel‐ or xerogel‐coated electrodes can easily be realized via inkjet printing. The main focus of this work is the implementation of the standard nanoparticle‐based gelation process in a commercial inkjet printing system. By simultaneously printing semiconductor nanoparticles and a destabilization agent, a 3D network on a conducting and transparent surface is obtained. First spectro‐electrochemical measurements are recorded to investigate the charge–carrier mobility within these 3D semiconductor‐based xerogel networks. 相似文献
98.
Sascha Kulas Christian Vogt Andreas Resch Jonas Hartwig Sven Ganske Jonas Matthias Dennis Schlippert Thijs Wendrich Wolfgang Ertmer Ernst Maria Rasel Marcin Damjanic Peter Weßels Anja Kohfeldt Erdenetsetseg Luvsandamdin Max Schiemangk Christoph Grzeschik Markus Krutzik Andreas Wicht Achim Peters Sven Herrmann Claus Lämmerzahl 《Microgravity science and technology》2017,29(1-2):37-48
99.
Matthias Droste Antti Jrvenp Matias Jaskari Mykhaylo Motylenko Anja Weidner Pentti Karjalainen Horst Biermann 《Fatigue & Fracture of Engineering Materials & Structures》2021,44(1):43-62
Different grain sizes were created in a metastable 17Cr‐7Mn‐7Ni steel by martensite‐to‐austenite reversion at different temperatures using a laser beam. Two fully reverted material states obtained at 990°C and 780°C exhibited average grain sizes of 7.7 and 2.7 μm, respectively. The third microstructure (610°C) consisted of grains at different stages of recrystallization and deformed austenite. A hot‐pressed, coarse‐grained counterpart was studied for reference. The yield and tensile strengths increased with refined grain size, maintaining reasonable elongation except for the heterogeneous microstructure. Total strain‐controlled fatigue tests revealed increasing initial stress amplitudes but decreasing cyclic hardening and fatigue‐induced α′‐martensite formation with decreasing grain size. Fatigue life was slightly improved for the 2.7‐μm grain size. Contrary, the heterogeneous microstructure yielded an inferior lifetime, especially at high strain amplitudes. Examinations of the cyclically deformed microstructure showed that the characteristic deformation band structure was less pronounced in refined grains. 相似文献
100.
Christian Müller Liangqi Ouyang Anja Lund Kasper Moth‐Poulsen Mahiar M. Hamedi 《Advanced materials (Deerfield Beach, Fla.)》2019,31(22)
Organic semiconductors are the centerpiece of several vibrant research fields from single‐molecule to organic electronics, and they are finding increasing use in bioelectronics and even classical polymer technology. The versatile chemistry and broad range of electronic functionalities of conjugated materials enable the bridging of length scales 15 orders of magnitude apart, ranging from a single nanometer (10?9 m) to the size of continents (106 m). This work provides a taste of the diverse applications that can be realized with organic semiconductors. The reader will embark on a journey from single molecular junctions to thin film organic electronics, supramolecular assemblies, biomaterials such as amyloid fibrils and nanofibrillated cellulose, conducting fibers and yarns for e‐textiles, and finally to power cables that shuffle power across thousands of kilometers. 相似文献