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Non-coding RNAs:the new central dogma of cancer biology

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Science China(Life Sciences) 2021年第1期64卷 22-50页

作者： Phei Er Saw Xiaoding Xu Jianing Chen Er-wei song Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation Sun Yat-sen Memorial HospitalSun Yat-sen UniversityGuangzhou510120China Breast Tumor Center Sun Yat-sen Memorial HospitalSun Yat-sen UniversityGuangzhou510120China

The central dogma of molecular biology states that the functions of RNA revolve around protein *** the last decade,most researches were geared towards characterization of RNAs as intermediaries in protein translation,namely,messenger RNAs(mRNAs)as temporary copies of genetic information,ribosomal RNAs(rRNAs)as a main component of ribosome,or translators of codon sequence(t RNAs).The statistical reality,however,is that these processes account for less than 2%of the genome,and insufficiently explain the functionality of 98%of transcribed *** discoveries have unveiled thousands of unique non-coding RNAs(ncRNAs)and shifted the perception of them from being"junk"transcriptional products to"yet to be elucidated"—and potentially monumentally important—*** ncRNAs are now known as key regulators in various networks in which they could lead to specific cellular responses and *** major cancers,ncRNAs have been identified as both oncogenic drivers and tumor suppressors,indicating a complex regulatory network among these ***,we provide a comprehensive review of the various ncRNAs and their functional roles in cancer,and the pre-clinical and clinical development of nc RNA-based therapeutics.A deeper understanding of ncRNAs could facilitate better design of personalized therapeutics.

关键词： non-coding RNAs anti-cancer therapeutics personalized intervention miRNA lncRNA circRNA

Ultrafine grained metastable Ti6Al4V5Cu alloy with high strength and excellent low-cycle fatigue property

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Journal of Materials Science & Technology 2022年第34期129卷 240-250页

作者： wei song Hai Wang Yi Li Shuyuan Zhang Ling Ren Ke Yang Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China

The insufficient low-cycle fatigue properties of titanium alloys under cyclic heavy loading are regarded as a challenge for their security in service. In recent years, a large number of studies have found that the transformation induced plasticity(TRIP) effect could hinder the propagation of fatigue cracks, which significantly improved the low-cycle fatigue properties of titanium alloys. However, the coarse β-phase grains and the soft phase transformation product α phase in TRIP titanium alloys impair their tensile strength, which restrict their applications in engineering. To this end, a Ti6Al4V5Cu alloy with TRIP effect was developed in this work. It was proposed to use the mutual restraint between the α and βphases in the material to refine the grains, and through composition optimization, the phase transformation product would be the α’ phase, which has a higher strength than the α phase. Thus, the strength of the Ti6Al4V5Cu alloy can be improved. The results showed that the tensile strength and elongation of the TRIP Ti6Al4V5Cu alloy was 1286 MPa and 22%, which was 23.7% and 46.7% higher than that of the traditional Ti6Al4V alloy, respectively. Besides, under the same strain amplitude, the fatigue life of the Ti6Al4V5Cu alloy was 2–5 times longer than that of the Ti6Al4V alloy. Furthermore, we clarified the mechanisms of improving the tensile strength and fatigue properties of the Ti6Al4V5Cu alloy, which would lay a research foundation for the development of high-performance titanium alloys.

关键词： Transformation induced plasticity Ti alloys Low-cycle fatigue Work hardening Crack propagation

Hydrodynamic Characteristics of the Biplane-Type Otter Board with the Canvas Through Flume−Tank Experiment

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China Ocean Engineering 2022年第6期36卷 911-921页

作者： XIE Si-jie WU Ru-ke HU Fu-xiang song wei-hua Department of Marine Fisheries Zhejiang Ocean UniversityZhoushan 316022China Key Laboratory of Marine Fishery Equipment and Technology of Zhejiang Zhoushan 316022China Tokyo University of Marine Science and Technology MinatoTokyo 108-8477Japan

Hydrodynamic characteristics of a biplane-type otter board,equipped with nylon canvas of 2 mm in thickness was investigated through flume-tank experiment in this study.A series of predesigned structures with different gap-chord ratios G/c(0.75,0.90,1.05),stagger anglesθ(30°,45°,60°),and proportions of flexible area relative to the whole wing areaƒr(0,55%,65%,75%),at an aspect ratio of 2.0 and a camber ratio of 15%,were experimentally carried *** results showed the solution referring to the usage of flexible canvas replacing part of rigid structure for the biplane-type otter board was efficient for the trawling in the middle or shallow water *** improvement of lift and stability for the biplane-type otter board was concluded,and drag of the structure was reduced by 1.9%atƒr=55%.In addition,the coefficient of variation of the lift and drag coefficient at different current velocities were 2.69%and 2.28%,respectively,which was smaller than those at relatively large proportion of the flexible *** with the other tested structures,the frame-type flexible structure with the gap-chord ratio of 0.9 and a stagger angle of 45°and the proportion of the flexible area of 55%,performed best,and its drag was reduced by 5.72%and lift increased by 4.8%,compared with the rigid biplane-type otter board at the angles of attack from 18°to 28°.

关键词： frame-type flexible structure hydrodynamic characteristics proportion of flexible area flume−tank experiment

Pressure-driven mold filling model of aluminum alloy melt/semi-solid slurry based on rheological behavior

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Journal of Materials Science & Technology 2020年第4期39卷 14-21页

作者： Zhen Ma Huarui Zhang wei song Xiaoyan Wu Lina Jia Hu Zhang School of Materials Science and Engineering Beihang UniversityBeijing100191China Qingdao Research Institute of Beihang University Qingdao266000China Ningbo Institute of Technology Beihang UniversityNingbo315832China

The pressure-driven mold filling ability of aluminum alloy melt/semi-solid slurry is of great significance in pressure casting processes,and the rheological behavior of the alloy has a crucial effect on the mold filling ability according to fluid *** this work,a pressure-driven mold filling model is first proposed based on the rheological behavior of the alloys.A356 alloy is employed as an example to clarify the rheological behavior of aluminum alloys,which obeys the power law model and is affected by *** rheological behavior of the alloy in semi-solid state is modelled with the coupling of shear rate and *** stop of mold filling attributes to the pressure loss which is caused by the viscosity during the flow of the melt/semi-solid *** loss caused by viscous flow and heat transfer between the alloy and the mold are calculated and coupled during the mold filling of the melt/semi-solid slurry.A pressure-driven mold filling model of aluminum alloy melt/semi-solid slurry is established based on steady-state rheological *** model successfully predicts the filling length of melt/semi-solid slurry in pressure casting *** with the experimental results,the model can provide a quantitative approach to characterize the pressure-driven mold filling ability of aluminum alloy *** model is capable of describing the stop filling behavior of other aluminum alloys in pressure casting processes with corresponding rheological parameters and heat transfer coefficient.

关键词： Mold filling model Fluidity Pressure-driven Rheological behavior Aluminum alloys Semi-solid state

Ozone episodes during and after the 2018 Chinese National Day holidays in Guangzhou:Implications for the control of precursor VOCs

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Journal of Environmental Sciences 2022年第4期34卷 322-333页

作者： Jun Wang Yanli Zhang Zhenfeng Wu Shilu Luo wei song Xinming Wang State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China CAS Center for Excellence in Regional Atmospheric Environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China University of Chinese Academy of Sciences Beijing 100049China

The impact of reducing industrial emissions of volatile organic compounds(VOCs)on ozone(O_(3))pollution is of wide concern particularly in highly industrialized *** this study,O_(3),nitrogen oxides(NOx)and VOCs were measured at an urban site in the Pearl River Delta region during the 2018 Chinese National Day Holidays and two after-holiday periods(one with ozone pollution and another without).O_(3)pollution occurred throughout the 7-day holidays even industrial emissions of VOCswere passively reduced due to temporary factory shutdowns,and the toluene to benzene ratios dropped from∼10 during non-holidays to∼5 during the *** model(AtChem2-MCM)simulations with the input of observation data revealed that O_(3)formation was all VOC-limited,and alkenes had the highest relative incremental reactivity(RIR)during the holiday and non-holiday O_(3)episodes while aromatics had the highest RIR during the non-pollution *** model also demonstrated that even aromatics decreased proportionally to levels with near-zero contributions of industrial aromatic solvents,O_(3)concentrations would only decrease by less than 20%during the holiday and non-holiday O_(3)episodes and ozone pollution in the periods could not be *** results imply that controlling emissions of industrial aromatic solvents might be not enough to eliminate O_(3)pollution in the region,and more attention should be paid to anthropogenic reactive *** and formaldehyde were among the top 3 species by RIRs in all the three pollution and non-pollution periods,suggesting substantial contribution to O_(3)formation from biogenic VOCs.

关键词： Ozone Ozone precursors Volatile organic compounds Box model Master Chemical Mechanism(MCM)

Interface-directed epitaxially growing nickle ensembles as efficient catalysts in dry reforming of methane

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Journal of Energy Chemistry 2022年第3期31卷 502-513,I0014页

作者： Ping Wang song wei Shiyi Wang Ronghe Lin Xiaoling Mou Yunjie Ding Hangzhou Institute of Advanced Studies Zhejiang Normal UniversityHangzhou 311231ZhejiangChina School of Chemical Engineering and Light Industry Guangdong University of Technology.Guangzhou 510006GuangdongChina Analysis and Test Center Guangdong University of TechnologyGuangzhou 510006GuangdongChina Dalian National Laboratory for Clean Energy Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina The State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina

Supported nickel catalysts are promising candidates for dry reforming of methane, but agglomeration of Ni^(0) and coke deposition hinder the industrial applications. Herein, we report a novel interface-directed synthetic approach to construct distinct metal ensembles by carefully tuning the compositions of the carriers. A Zr-Mn-Zn ternary oxide-supported Ni catalyst, together with the respective binary oxide-supported analogues, was synthesized by adopting a sequential co-precipitation and wetness impregnation method. Combined characterization techniques identify distinct catalyst models, including (i) conventional NiO nanoparticles with different sizes on Zr-Mn and Zr-Zn, and (ii) epitaxially growing NiO ensembles of a few nanometers thickness at the periphery of ZnO_(x) particles. These catalysts exhibit divergent responses in the catalytic testing, with the ternary oxide system significantly outperforming the binary analogues. The strong electronic interactions between Mn-Ni increase Ni dispersion and the activity while the stability is strengthened upon Zn addition. Both high activity, high selectivity, and remarkable stability are attained upon co-adding Mn and Zn. The interfaces between Ni and Zr-Mn-Zn rather than the physical contacts of individual oxide-supported analogues through mechanical mixing are keys for the outstanding performance.

关键词： Methane dry reforming Nickel Interface Epitaxial growth Structure-performance relationship

Effect of Nitrogen Starvation on the Responses of Two Rice Cultivars to Nitrate Uptake and Utilization

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Pedosphere 2014年第5期24卷 690-698页

作者： YIN Xiao-Ming LUO wei WANG song-wei SHEN Qi-Rong LONG Xiao-Hua College of Resources and Environmental Sciences Nanjing Agricultural University

Ammonium(NH+4) is the main nitrogen(N) form for rice crops, while NH+4near the root surface can be oxidized to nitrate(NO-3)by NH+4-oxidizing bacteria. Nitrate can be accumulated within rice tissues and reused when N supply is insufficient. We compared the remobilization of NO-3stored in the tissue and vacuolar between two rice(Oryza sativa L.) cultivars, Yangdao 6(YD6, indica)with a high N use efficiency(NUE) and Wuyujing 3(WYJ3, japonica) with a low NUE and measured the uptake of NO-3, expression of nitrate reductase(NR), NO-3transporter genes(NRTs), and NR activity after 4 d of N starvation following 7-d cultivation in a solution containing 2.86 mmol L-1NO-3. The results showed that both tissue NO-3concentration and vacuolar NO-3activity were higher in YD6 than WYJ3 under N starvation. YD6 showed a 2- to 3-fold higher expression of OsNRT2.1 in roots on the 1st and 4th day of N starvation and had significantly higher values of NO-3uptake(maximum uptake velocity, Vmax) than the cultivar ***, YD6 had significantly higher leaf and root maximum NR activity(NRAmax) and actual NR activity(NRAact) as well as stronger root expression of the two NR genes after the 1st day of N starvation. There were no significant differences in NRAmax and NRAact between the two rice cultivars on the 4th day of N starvation. The results suggested that YD6 had stronger NRA under N starvation, which might result in better NO-3re-utilization from the vacuole, and higher capacity for NO-3uptake and use, potentially explaining the higher NUE of YD6 compared with WYJ3.

关键词： nitrate reductase activity nitrate transpoters nitrogen use efficiency Oryza sativa L. remobilization

Effects of temperature on pyrolysis products of oil sludge

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Frontiers of Environmental Science & Engineering 2008年第1期2卷 8-14页

作者： Jianguo LIU wei song Yongfeng NIE Department of Environmental Science and Engineering Tsinghua UniversityBeijing 100084China

Temperature is the determining factor of pyro-lysis,which is one of the alternative technologies for oil sludge *** effects of final operating temper-ature ranging from 350 to 550uC on pyrolysis products of oil sludge were studied in an externally-heating fixed bed *** an increase of temperature,the mass fraction of solid residues,liquids,and gases in the final product is 67.00%–56.00%,25.60%–32.35%,and 7.40%–11.65%,and their corresponding heat values are 34.4–13.8 MJ/kg,44.41–46.6 MJ/kg,and 23.94–48.23 MJ/Nm 3,*** mass and energy tend to shift from solid to liquid and gas phase(especially to liquid phase)during the process,and the optimum temperature for oil sludge pyrolysis is *** liquid phase is mainly com-posed of alkane and alkene(C_(5)–C_(29)),and the gas phase is dominantly HC S and H 2.

关键词： oil sludge pyrolysis temperature fixed bed reactor pyrolysis products

Visualizing diffusion tensor fields on streamsurfaces with merging ellipsoids

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Applied Mathematics(A Journal of Chinese Universities) 2014年第4期29卷 399-409页

作者： song wei-jie CHEN wei CHEN Hai-dong ZHENG Hong-chan CUI Jun-zhi School of Science Northwestern Polytechnical University State Key Lab of CADCG Zhejiang University Academy of Mathematics and System Sciences Chinese Academy of Sciences

Streamsurfaces in diffusion tensor fields are used to represent structures with pri- marily planar diffusion. So far, however, no effort has been made on the visualization of the anisotropy of diffusion on them, although this information is very important to identify the problematic regions of these structures. We propose two methods to display this anisotropy information. The first one employs a set of merging ellipsoids, which simultaneously character- ize the local tensor details - anisotropy - on them and portray the shape of the streamsurfaces. The weight between the streamsurfaces continuity and the discrete local tensors can be inter- actively adjusted by changing some given parameters. The second one generates a dense LIC （line integral convolution） texture of the two tangent eigenvector fields along the streamsurfaces firstly, and then blends in some color mapping indicating the anisotropy information. For high speed and high quality of texture images, we confine both the generation and the advection of the LIC texture in the image space. Merging ellipsoids method reveals the entire anisotropy information at discrete points by exploiting the geometric attribute of ellipsoids, and thus suits for local and detailed examination of the anisotropy; the texture-based method gives a global representation of the anisotropy on the whole streamsurfaces with texture and color attributes. To reveal the anisotropy information more efficiently, we integrate the two methods and use them at two different levels of details.

关键词： visualization anisotropy diffusion tensor field streamsurface merging ellipsoid LIC.