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Maria Smolle Stefan Uranitsch Armin Gerger Martin Pichler Johannes Haybaeck 《International journal of molecular sciences》2014,15(8):13993-14013
The latest investigations of long non-coding RNAs (lncRNAs) have revealed their important role in human cancers. LncRNAs are larger than 200 nucleotides in length and fulfill their cellular purpose without being translated into proteins. Though the molecular functions of some lncRNAs have been elucidated, there is still a high number of lncRNAs with unknown or controversial functions. In this review, we provide an overview of different lncRNAs and their role in human cancers. In particular, we emphasize their importance in tumorigenesis of colorectal cancer, the third most common cancer worldwide. 相似文献
74.
当今时代最大的环境挑战是城市和建筑对化石燃料的依赖,以及对能源、土地、水和食品安全日益增长的需求。在这一背景下,城市需向更可持续的城镇化模式转变,建筑和城市规划在这一过程中发挥主要作用。为此提出了15项绿色城市法则,以应对现存街区、区域和城市转型的挑战,并对中国低碳或无碳的未来进行了展望。 相似文献
75.
Felix Schubert Steffen Wirth Friederike Zimmermann Johannes Heitmann Thomas Mikolajick 《Science and Technology of Advanced Materials》2016,17(1):239-243
Growth conditions have a tremendous impact on the unintentional background impurity concentration in gallium nitride (GaN) synthesized by molecular beam epitaxy and its resulting chemical and physical properties. In particular for oxygen identified as the dominant background impurity we demonstrate that under optimized growth stoichiometry the growth temperature is the key parameter to control its incorporation and that an increase by 55?°C leads to an oxygen reduction by one order of magnitude. Quantitatively this reduction and the resulting optical and electrical properties are analyzed by secondary ion mass spectroscopy, photoluminescence, capacitance versus voltage measurements, low temperature magneto-transport and parasitic current paths in lateral transistor test structures based on two-dimensional electron gases. At a growth temperature of 665?°C the residual charge carrier concentration is decreased to below 1015 cm?3, resulting in insulating behavior and thus making the material suitable for beyond state-of-the-art device applications. 相似文献
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Norbert Eisenreich Armin KeßlerAndreas Koleczko Volker Weiser 《International Journal of Hydrogen Energy》2014
Metal hydrides are used for hydrogen storage. AlH3 shows a capacity to store about 10 wt% hydrogen. Its hydrogen is split-off in the temperature interval of 400–500 K. On dehydrogenation a nano-structured Al material emerges with specific surfaces up to 15–20 m2/g. The surface areas depend on the heating rate because of a temperature dependent crystallite growth. The resulting Al oxidizes up to 20–25% weight on air access forming an alumina passivation layer of 3–4 nm thickness on all exposed surfaces. The heat released from this Al oxidation induces a high risk to this type of hydrogen storage if the containment might be destroyed, accidentally. The kinetics of the dehydrogenation and the subsequent oxidation is investigated by methods of thermal analysis. A reaction scheme is confirmed which consists of a starting Avrami-Erofeev mechanism followed by formal 1st order oxidation on unlimited air access. The kinetic parameters, activation energies and pre-exponentials are evaluated and can be used to calculate the reaction progress. Together with the heat of the Al oxidation the overall heat release and the related rate can be estimated. 相似文献
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79.
Suhaib Koji Baydoun Matthias Voigt Christopher Jelich Steffen Marburg 《International journal for numerical methods in engineering》2020,121(2):187-200
The solution of frequency dependent linear systems arising from the discretization of vibro-acoustic problems requires a significant computational effort in the case of rapidly varying responses. In this paper, we review the use of a greedy reduced basis scheme for the efficient solution in a frequency range. The reduced basis is spanned by responses of the system at certain frequencies that are chosen iteratively based on the response that is currently worst approximated in each step. The approximations at intermediate frequencies as well as the a posteriori estimations of associated errors are computed using a least squares solver. The proposed scheme is applied to the solution of an interior acoustic problem with boundary element method (BEM) and to the solution of coupled structural acoustic problems with finite element method and BEM. The computational times are compared to those of a conventional frequencywise strategy. The results illustrate the efficiency of the method. 相似文献
80.
Mirzapour-Kouhdasht Armin Lee Chul Won Yun Hyosuk Eun Jong-Bang 《Food science and biotechnology》2021,30(13):1685-1693
Food Science and Biotechnology - In this study, we investigated the multi-functionality of bioactive peptides derived from fermented skate (Raja kenojei) skin gelatin hydrolysates. The extracted... 相似文献