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Network analysis based on low-rank method for mining information on integrated data of multi-cancers
The noise problem of cancer sequencing data has been a problem that can’t be ignored. Utilizing considerable way to reduce noise of these cancer data is an important issue in the analysis of gene co-expression network. In this paper, we apply a sparse and low-rank method which is Robust Principal Component Analysis (RPCA) to solve the noise problem for integrated data of multi-cancers from The Cancer Genome Atlas (TCGA). And then we build the gene co-expression network based on the integrated data after noise reduction. Finally, we perform nodes and pathways mining on the denoising networks. Experiments in this paper show that after denoising by RPCA, the gene expression data tend to be orderly and neat than before, and the constructed networks contain more pathway enrichment information than unprocessed data. Moreover, learning from the betweenness centrality of the nodes in the network, we find some abnormally expressed genes and pathways proven that are associated with many cancers from the denoised network. The experimental results indicate that our method is reasonable and effective, and we also find some candidate suspicious genes that may be linked to multi-cancers. 相似文献
3.
Xiao Liang Mei Chen Qian Wang Shaojun Guo Huai Yang 《Angewandte Chemie (International ed. in English)》2019,58(9):2799-2803
Perovskite nanocrystals (PNCs) are emerging luminescent materials due to their fascinating physic‐optical properties. However, their sensitive surface chemistry with organic polar solvents, oxygen, and moisture greatly hinders their developments towards practical applications. Herein we promote silica‐passivated PNCs (SP‐PNCs) by in situ hydrolyzing the surface ligands of (3‐aminopropyl) triethoxysilane. The resultant SP‐PNCs possesses a high quantum yield (QY) of 80 % and are precipitable by polar solvents, such as ethanol and acetone, without destroying their surface chemistry or losing QY, which offers an eco‐friendly and efficient method for separation, purification, and phase transfer of PNCs. Moreover, we further promoted a swelling–deswelling encapsulation process to incorporate the as‐made SP‐PNCs into non‐crosslinked polystyrene microspheres (PMs), which can largely increase the stability of the SP‐PNCs against moisture for long‐term storage. 相似文献
4.
The morphology evolution of carbide precipitated on grain boundary nearby different triple junctions in grain boundary engineering (GBE) treated nickel-based Inconel Alloy 690 aged at 715°C for different time was investigated by scanning electron microscopy and electron backscatter diffraction. The results show that, the diversity of triple junction types was increased by GBE significantly. The size and morphology of grain boundary carbide were not only affected by the grain boundary character, but also the nearby grain boundary character at the triple junction. The higher Σ values of the nearby grain boundaries, the larger carbide precipitated on the other grain boundary. Based on the experimental results, the effects of grain boundary characters and triple junction types on the carbide precipitation behaviours are discussed. 相似文献
5.
Yanni Zhang Jianfeng Zhao Caixia Zhu Lifang Bian Huifang Shi Shiming Zhang Huili Ma Wei Huang 《中国化学快报》2019,30(11):1974-1978
Organic phosphorescence materials demonstrate potential optoelectronic applications due to their remarkably ultralong organic phosphorescence (UOP) lifetime and abundant optical characteristics prior to the fluorescence materials. For a better insight into the intrinsic relationship among regioisomeric molecules, crystalline interactions, and phosphorescence properties, three crystalline dicarbazol-9-yl pyrazine-based regioisomers with para-, meta-, and ortho-convergent substitutions (p-DCzP, m-DCzP, and o-DCzP) were designed and presented gradually increased UOP lifetimes prolonging from 63.14, 127.93 to 350.46 ms, respectively, due to the regioisomerism effect (RIE) which would be an effective strategy for better understanding of structure-property of UOP materials. 相似文献
6.
Zhitao Cui Wei Du Chengwei Xiao Qiaohong Li Rongjian Sa Chenghua Sun Zuju Ma 《Frontiers of Physics》2020,15(6):63502
MoS2 is a promising candidate for hydrogen evolution reaction (HER), while its active sites are mainly distributed on the edge sites rather than the basal plane sites. Herein, a strategy to overcome the inertness of the MoS2 basal surface and achieve high HER activity by combining single-boron catalyst and compressive strain was reported through density functional theory (DFT) computations. The ab initio molecular dynamics (AIMD) simulation on B@MoS2 suggests high thermodynamic and kinetic stability. We found that the rather strong adsorption of hydrogen by B@MoS2 can be alleviated by stress engineering. The optimal stress of −7% can achieve a nearly zero value of ΔGH (~ −0.084 eV), which is close to that of the ideal Pt–SACs for HER. The novel HER activity is attributed to (i) the B– doping brings the active site to the basal plane of MoS2 and reduces the band-gap, thereby increasing the conductivity; (ii) the compressive stress regulates the number of charge transfer between (H)–(B)–(MoS2), weakening the adsorption energy of hydrogen on B@MoS2. Moreover, we constructed a SiN/B@MoS2 heterojunction, which introduces an 8.6% compressive stress for B@MoS2 and yields an ideal ΔGH. This work provides an effective means to achieve high intrinsic HER activity for MoS2. 相似文献
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8.
Dr. Qi Hu Guomin Li Zhen Han Ziyu Wang Xiaowan Huang Dr. Hengpan Yang Prof. Qianling Zhang Prof. Jianhong Liu Prof. Chuanxin He 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(18):3930-3942
Recently, nonmetal doping has exhibited its great potential for boosting the hydrogen evolution reaction (HER) of transition-metal (TM)-based electrocatalysts. To this end, this work overviews the recent achievements made on the design and development of the nonmetal-doped TM-based electrocatalysts and their performance for the HER. It is also shown that by rationally doping nonmetal elements, the electronic structures of TM-based electrocatalysts can be effectively tuned and in turn the Gibbs free energy of the TM for adsorption of H* intermediates (ΔGH*) optimized, consequently enhancing the intrinsic activity of TM-based electrocatalysts. Notably, we highlight that concurrently doping two nonmetal elements can continuously and precisely regulate the electronic structures of the TM, thereby maximizing the activity for HER. Moreover, nonmetal doping also accounts for enhancing the physical properties of the TM (i.e. surface area). Therefore, nonmetal doping is a robust strategy for simultaneous regulation of the chemical and physical features of the TM. 相似文献
9.
Dr. Haixiang Han Jesse C. Carozza Audra P. Colliton Yuxuan Zhang Dr. Zheng Wei Dr. Alexander S. Filatov Prof. Dr. Yu-Sheng Chen Melisa Alkan Prof. Dr. Andrey Yu. Rogachev Prof. Dr. Evgeny V. Dikarev 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(24):9711-9717
A known trinuclear structure was used to design the heterobimetallic mixed-valent, mixed-ligand molecule [CoII(hfac)3−Na−CoIII(acac)3] ( 1 ). This was used as a template structure to develop heterotrimetallic molecules [CoII(hfac)3−Na−FeIII(acac)3] ( 2 ) and [NiII(hfac)3−Na−CoIII(acac)3] ( 3 ) via isovalent site-specific substitution at either of the cobalt positions. Diffraction methods, synchrotron resonant diffraction, and multiple-wavelength anomalous diffraction were applied beyond simple structural investigation to provide an unambiguous assignment of the positions and oxidation states for the periodic table neighbors in the heterometallic assemblies. Molecules of 2 and 3 are true heterotrimetallic rather than a statistical mixture of two heterobimetallic counterparts. Trinuclear platform 1 exhibits flexibility in accommodating a variety of di- and trivalent metals, which can be further utilized in the design of molecular precursors for the NaMM′O4 functional oxide materials. 相似文献
10.
《Current Applied Physics》2020,20(9):1073-1079
We study emissivity (ε)-dependent radiative heat transfer phenomena in remote and contact configurations. To demonstrate the emissivity-dependent radiative heating mode in a remote configuration, we fabricated miniature greenhouses covered with low (0.34)- and high-ε (0.86) polyethylene films and monitored temperatures on the floors, insides, and covers of the greenhouses during 24 h. The high-ε greenhouse yielded a 9-°C increase in floor temperature relative to the low-ε greenhouse at a one-sun solar irradiance because the high-ε film effectively trapped floor radiation. In contrast, the cover temperature remained lower in the high-ε greenhouse due to intensified radiation released from the high-ε film. This self-cooling effect was more evident when an emissive film was in physical contact with an object. While bare copper heated up to 55 °C, a high-ε film coated copper substrate was kept cooler by 4 and 2 °C compared with the bare and low-ε film coated copper samples, respectively. 相似文献