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961.
The Flory isolated pair hypothesis (IPH) is one of the corner stones of the random coil model, which is generally invoked to describe the conformational dynamics of unfolded and intrinsically disordered proteins (IDPs). It stipulates, that individual residues sample the entire sterically allowed space of the Ramachandran plot without exhibiting any correlations with the conformational dynamics of its neighbors. However, multiple lines of computational, bioinformatic and experimental evidence suggest that nearest neighbors have a significant influence on the conformational sampling of amino acid residues. This implies that the conformational entropy of unfolded polypeptides and proteins is much less than one would expect based on the Ramachandran plots of individual residues. A further implication is that the Gibbs energies of residues in unfolded proteins or polypeptides are not additive. This review provides an overview of what is currently known and what has yet to be explored regarding nearest neighbor interactions in unfolded proteins. 相似文献
962.
提出基于粗糙集理论的动态类别扩展算法,可以根据新文献与已有训练规则的匹配程度,有效地进行新类别的自动扩展和新分类规则的自动生成,从而屏蔽训练集和分类规则的更新等问题. 相似文献
963.
Mihai Irimia‐Vladu Pavel A. Troshin Melanie Reisinger Lyuba Shmygleva Yasin Kanbur Günther Schwabegger Marius Bodea Reinhard Schwödiauer Alexander Mumyatov Jeffrey W. Fergus Vladimir F. Razumov Helmut Sitter Niyazi Serdar Sariciftci Siegfried Bauer 《Advanced functional materials》2010,20(23):4069-4076
Biocompatible‐ingestible electronic circuits and capsules for medical diagnosis and monitoring are currently based on traditional silicon technology. Organic electronics has huge potential for developing biodegradable, biocompatible, bioresorbable, or even metabolizable products. An ideal pathway for such electronic devices involves fabrication with materials from nature, or materials found in common commodity products. Transistors with an operational voltage as low as 4–5 V, a source drain current of up to 0.5 μA and an on‐off ratio of 3–5 orders of magnitude have been fabricated with such materials. This work comprises steps towards environmentally safe devices in low‐cost, large volume, disposable or throwaway electronic applications, such as in food packaging, plastic bags, and disposable dishware. In addition, there is significant potential to use such electronic items in biomedical implants. 相似文献
964.
Mohammad ZOUNEMAT-KERMANI Meysam ALIZAMIR Zaher Mundher YASEEN Reinhard HINKELMANN 《Frontiers of Structural and Civil Engineering》2021,15(2):444-460
The implementation of novel machine learning models can contribute remarkably to simulating the degradation of concrete due to environmental factors. This study considers the sulfuric acid corrosive factor in wastewater systems to simulate concrete mass loss using five machine learning models. The models include three different types of extreme learning machines, including the standard, online sequential, and kernel extreme learning machines, in addition to the artificial neural network, classification and regression tree model, and statistical multiple linear regression model. The reported values of concrete mass loss for six different types of concrete are the target values of the machine learning models. The input variability was assessed based on two scenarios prior to the application of the predictive models. For the first assessment, the machine learning models were developed using all the available cement and concrete mixture input variables; the second assessment was conducted based on the gamma test approach, which is a sensitivity analysis technique. Subsequently, the sensitivity analysis of the most effective parameters for concrete corrosion was tested using three different approaches. The adopted methodology attained optimistic and reliable modeling results. The online sequential extreme learning machine model demonstrated superior performance over the other investigated models in predicting the concrete mass loss of different types of concrete. 相似文献
965.
K. Jhnisch H. Seeboth E. Krause D. R. Callejas 《Advanced Synthesis \u0026amp; Catalysis》1984,326(4):556-560
β-Fur-2-yl-α-halogenacrylonitriles. I. Preparation of β-Fur-2-yl-ß-aminoacrylonitriles and β-Fur-2-yl-α-aminoacrylonitriles β-Fur-2-yl-α-halogenacrylonitriles 1 react with secondary amines to yield β-fur-2-yl-ß-aminonitriles 2 and β-fur-2-yl-α-aminoacrylonitriles 3 . The 1 H-n.m.r. spectra of the E/Z isomers are discussed. 相似文献
966.
967.
公众参与近年来在我国已引起越来越多的关注,但居民和社区参与的实践操作还很少.社区行动规划是发动居民参与社区规划和建设的一种方法,国际上已有较为成功的运用.德国技术合作公司(GTZ)和扬州市政府引入社区行动规划方法,鼓励居民参与历史街区的保护并改善自身的居住条件,在实践中尝试了老城保护中的公众参与方法. 相似文献
968.
Reinhard Kuhn 《电子工业专用设备》2008,37(7)
半导体工业的集中化程度在不断提高,半导体结构越来越精细,因此其生产过程和其测量及检测过程需要更高的纳米级定位精度。导轨方向误差和热膨胀导致的测量误差现在仍无法通过计算进行补偿,但可被新型测量设备确定并将其大幅减小。"要改变,必须先测量。 相似文献
969.
Reinhard Irrgang 《现代制造》2022,(2):28-30
<正>集装箱叉车是物流码头不可或缺的重要设备。例如,满载集装箱堆垛叉车就可以轻松地完成总重量52 t的集装箱搬运和堆垛,就可以轻松地将装满货物的40 in集装箱从货船上卸下来装到载重卡车上,可以将九个空载集装箱堆叠在一起。 相似文献
970.
Jie Luo Miriam Hhn Sren Reinhard Dominik M. Loy Philipp Michael Klein Ernst Wagner 《Advanced functional materials》2019,29(25)
Targeted delivery remains the major limitation in the development of small interfering RNA (siRNA) therapeutics. The successful siRNA multistep delivery requires precise carriers of substantial complexity. To achieve this, a monodisperse carrier is presented, synthesized by solid‐phase supported chemistry. The sequence‐defined assembly contains two oleic acids attached to a cationizable oligoaminoamide backbone in T‐shape configuration, and a terminal azide functionality for coupling to the atherosclerotic plaque‐specific peptide‐1 (AP‐1) as the cell targeting ligand for interleukin‐4 receptor (IL‐4R) which is overexpressed in a variety of solid cancers. For combined cytosolic delivery with siRNA, different apoptotic peptides (KLK, BAK, and BAD) are covalently conjugated via bioreversible disulfide linkage to the 5′‐end of the siRNA sense strand. siRNA‐KLK conjugates provide the highest antitumoral potency. The optimized targeted carrier is complexed with dual antitumoral siEG5‐KLK conjugates. The functionality of each subdomain is individually confirmed. The lipo‐oligomer confers stable assembly of siRNA conjugates into spherical 150–250 nm sized nanoparticles. Click‐shielding with dibenzocyclootyne‐PEG‐AP‐1 (DBCO‐PEG‐AP‐1) mediates an IL‐4R‐specific cell targeting and gene silencing in tumor cells. Most importantly, formulation of the siEG5‐KLK conjugate displays enhanced apoptotic tumor cell killing due to the combined effect of mitotic arrest by EG5 gene silencing and mitochondrial membrane disruption by KLK. 相似文献