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| 1 | SURFACE STRESS EFFECT IN MECHANICS OF NANOSTRUCTURED MATERIALS显示文摘This review article summarizes the advances in the surface stress effect in mechanics of nanostructured elements,including nanoparticles,nanowires,nanobeams,and nanofilms,and heterogeneous materials containing nanoscale inhomogeneities.It begins with the fundamental formulations of surface mechanics of solids,including the definition of surface stress as a surface excess quantity,the surface constitutive relations,and the surface equilibrium equations.Then,it depicts some theoretical and experimental studies of the mechanical properties of nanostructured elements,as well as the static and dynamic behaviour of cantilever sensors caused by the surface stress which is influenced by adsorption.Afterwards,the article gives a summary of the analytical elasto-static and dynamic solutions of a single as well as multiple inhomogeneities embedded in a matrix with the interface stress prevailing.The effect of surface elasticity on the diffraction of elastic waves is elucidated.Due to the difficulties in the analytical solution of inhomogeneities of complex shapes and configurations,finite element approaches have been developed for heterogeneous materials with the surface stress.Surface stress and surface energy are inherently related to crack propagation and the stress field in the vicinity of crack tips.The solutions of crack problems taking into account surface stress effects are also included.Predicting the effective elastic and plastic responses of heterogeneous materials while taking into account surface and interface stresses has received much attention.The advances in this topic are inevitably delineated.Mechanics of rough surfaces appears to deserve special attention due to its theoretical and practical implications.Some most recent work is reviewed.Finally,some challenges are pointed out.They include the characterization of surfaces and interfaces of real nanomaterials,experimental measurements and verification of mechanical parameters of complex surfaces,and the effects of the physical and chemical processes on the surface properties,etc. | Jianxiang Wang Zhuping Huang Huiling Duan Shouwen Yu Xiqiao Feng Gangfeng Wang Weixu Zhang Tiejun Wang | 2011 | Acta Mechanica Solida Sinica2011，24，1： | 11 |
| 2 | Enhancement of precursor amino acid supplies for improving bacitracin production by activation of branched chain amino acid transporter BrnQ and deletion of its regulator gene lrp in Bacillus licheniformis显示文摘Bacitracin,a new type of cyclic peptide antibiotic,is widely used as the feed additive in feed industry.Branched chain amino acids(BCAAs)are the key precursors for bacitracin synthesis.In this research,soybean meal was served as the raw material to supply precursor amino acids for bacitracin synthesis,and enhanced production of bacitracin was attempted by engineering BCAA transporter BrnQ and its regulator Lrp in the bacitracin industrial production strain Bacillus licheniformis DW2.Firstly,our results confirmed that Lrp negatively affected bacitracin synthesis in DW2,and deletion of lrp improved intracellular BCAA accumulations,as well as the expression level of BCAA transporter BrnQ,which further led to a 14.71%increase of bacitracin yield,compared with that of DW2.On the contrary,overexpression of Lrp decreased bacitracin yield by 12.28%.Secondly,it was suggested that BrnQ acted as a BCAA importer in DW2,and overexpression of BrnQ enhanced the intracellular BCAA accumulations and 10.43%of bacitracin yield.While,the bacitracin yield decreased by 18.27%in the brnQ deletion strain DW2△brnQ.Finally,BrnQ was further overexpressed in lrp deletion strain DW2△lrp,and bacitracin yield produced by the final strain DW2△lrp::BrnQ was 965.34 U/mL,increased by 22.42%compared with that of DW2(788.48 U/mL).Collectively,this research confirmed that Lrp affected bacitracin synthesis via regulating the expression of BCAA transporter BrnQ and BCAA distributions,and provided a promising strain for industrial production of bacitracin. | Jiang Zhu Dongbo Cai Haixia Xu Ziwei Liu Bowen Zhang Fei Wu Junhui Li Shouwen Chen | 2018 | Synthetic and Systems Biotechnology2018，3，4： | 6 |
| 3 | Natural and engineered bacterial outer membrane vesicles显示文摘Bacterial outer membrane vesicle(OMV)is a kind of spherical lipid bilayer nanostructure naturally secreted by bacteria,which has diverse functions such as intracellular and extracellular communication,horizontal gene transfei;transfer of contents to host cells,and eliciting an immune response in host cells.In this review,several methods including ultracentrifugation and precipNation for isolating OMVs were summarized.The latest progresses of OMVs in biomedical fields,especially in vaccine development,cancer treatment,infection control,and bioimaging and detection were also summarized in this review.We highlighted the importance of genetic engineering for the safe and effective application and in facilitating the rapid development of OMVs.Finally,we discussed the bottleneck problems about OMVs in preparation and application at present and put forward our own suggestions about them.Some perspectives of OMVs in biomedical field were also provided. | Guangchao Qing Ningqiang Gong Xiaohui Chen Jing Chen Hong Zhang Yongchao Wang Ruifang Wang Shouwen Zhang Zhen Zhang Xianxian Zhao Yang Luo Xing-Jie Liang | 2019 | Biophysics Reports2019，5，4： | 4 |
| 4 | Targeted nanoparticles for precise cancer therapy显示文摘Cancer has become one of the biggest challenges in the development of modern medical science. In particular, many problems, such as low efficiency, severe side effects, metastasis, and tumor invasion, challenge the development of precise cancer therapy. Continuous advancements in medicine, however, have allowed clear differentiation between tumors and normal tissues that can be exploited for cancer therapeutics. Unlike normal cells, tumor cells have an uncontrollable growth and are infinitely proliferative. These physical, chemical, and biological differences (e.g., metabolic states, high cell density, ability to grow in hypoxic and low pH conditions, and expression of different specific receptors/ ligands) may provide a new perspective for the development of cancer therapeutics. Traditional antitumor drugs have disadvantages, such as poor solubility, insufficient bioavailability in the body, numerous side effects, and development of chemoresistance, all of which greatly limit their therapeutic efficacy. | Jinjin Wang Yongchao Wang Ruifang Wang Shouwen Zhang Xiaoxuan Liu Xing-Jie Liang | 2019 | Science China(Life Sciences)2019，62，10： | 2 |
| 5 | Potential effects of subduction rate in the key ocean on global warming hiatus显示文摘In this study, the possible effects of subduction rate on global warming hiatus were investigated using Simple Ocean Data Assimilation(SODA) data. This study first analyzed the characteristics of the temporal and spatial distribution of global subduction rate, which revealed that the North Atlantic meridional overturning circulation region and the Antarctic Circumpolar Current region are the two main sea areas with great subduction variations.On this basis, four key areas were selected to explore the relationship between the local subduction rate and the global mean sea surface temperature. In addition, the reason for the variations in subduction rate was preliminarily explored. The results show good correspondence of the subduction of the key areas in the North Atlantic meridional overturning the circulation region and the Antarctic Circumpolar Current region to the global warming hiatus, with the former leading by about 10 years. The subduction process may be a physical mechanism by which the North Atlantic overturning circulation and the Antarctic Circumpolar Current act on the stagnation of global warming. Advection effect plays an important role in the variations in subduction in the key regions. In the Antarctic Circumpolar Current region, the magnitude of sea surface wind stress is closely related to the local changes in subduction. | CHEN Xingrong LIU Shan CAI Yi ZHANG Shouwen | 2018 | Acta Oceanologica Sinica2018，37，3： | 2 |
| 6 | Enhanced production of poly-γ-glutamic acid via optimizing the expression cassette of Vitreoscilla hemoglobin in Bacillus licheniformis显示文摘Poly-γ-glutamic acid(γ-PGA)is a natural polymer with various applications,and its high-viscosity hinders ox-ygen transmission and improvement of synthesis level.Vitreoscilla hemoglobin(VHB)has been introduced into various hosts as oxygen carrier,however,its expression strength and contact efficiency with oxygen hindered efficient oxygen transfer and metabolite synthesis.Here,we want to optimize the expression cassette of VHB for γ-PGA production.Firstly,our results implied that γ-PGA yields were enhanced when introducing twin-arginine translocation(Tat)signal peptides(SP_(YwbN),SP_(PhoD) and SP_(TorA))into VHB expression cassette,and the best per-formance was attained by SP YwbN from Bacillus subtilis,theγ-PGA yield of which was 18.53% higher than that of control strain,and intracellular ATP content and oxygen transfer coefficient(K_(L)a)were increased by 29.71% and 73.12%,respectively,indicating that VHB mediated by SP YwbN benefited oxygen transfer and ATP generation forγ-PGA synthesis.Furthermore,four promoters were screened,and P vgb was proven as the more suitable promoter for VHB expression andγ-PGA synthesis,andγ-PGA yield of attaining strain WX/pPvgb-YwbN-Vgb was further increased to 40.59 g/L by 10.18%.Finally,WX/pPvgb-YwbN-Vgb was cultivated in 3 L fermentor for fed-batch fermentation,and 46.39 g/Lγ-PGA was attained by glucose feeding,increased by 49.26%compared with the initial yield(31.01 g/L).Taken together,this study has attained an efficient VHB expression cassette for oxygen transfer andγ-PGA synthesis,which could also be applied in the production of other metabolites. | Qing Zhang Yaozhong Chen Lin Gao Jian’gang Chen Xin Ma Dongbo Cai Dong Wang Shouwen Chen | 2022 | Synthetic and Systems Biotechnology2022，7，1： | 2 |
| 7 | Spectral and Spatial Decorrelation of Landsat-TM Data for Lossless Compression显示文摘 | Wang Jinfei Zhang Kaizhong Tang Shouwen | 1995 | Transactions on Geoscience and Remote Sensing1995，33，5： | 1 |
| 8 | Representative value of cross-fault in the northeastern margin of the Qinghai-Tibet block and case analysis of the 2016 Menyuan Ms6.4 earthquake显示文摘The equation for determining cross-fault representative value is calculated based on hanging wall and foot wall reference level surfaces. The cross-fault data reliability are analyzed base on the stability of reference datum and observation points, thereby facilitating plotting of the representative value curves after removing interference. The spatial and temporal characteristics of fault deformation abnormalities before the 2016 Menyuan Ms6.4 earthquake, as well as the fault-movement characteristics reflected by representative value, are summarized. The results show that many site trends had changed 1-3 years before the Menyuan Ms6.4 earthquake in the Qilian Fault, reflecting certain background abnormalities. The short-term abnormalities centrally had appeared in the 6 months to 1 year period before the earthquake near and in the neighborhood of the source region,demonstrating a significantly increased number of short-term abnormalities. Many sites near and in the neighborhood of the source region had strengthened inverse activities or had changed from positive to inverse activities in the most recent 2-3 years, which reflect stress-field enhancements or adjustment features. | Ruisha Li Xi Zhang Shouwen Gong Hongtao Tang Peng Jia | 2016 | Geodesy and Geodynamics2016，7，4： | 1 |
| 9 | A new nudging scheme for the current operational climate prediction system of the National Marine Environmental Forecasting Center of China显示文摘A new nudging scheme is proposed for the operational prediction system of the National Marine Environmental Forecasting Center(NMEFC)of China,mainly aimed at improving El Niño–Southern Oscillation(ENSO)and Indian Ocean Dipole(IOD)predictions.Compared with the origin nudging scheme of NMEFC,the new scheme adds a nudge assimilation for wind components,and increases the nudging weight at the subsurface.Increasing the nudging weight at the subsurface directly improved the simulation performance of the ocean component,while assimilating low-level wind components not only affected the atmospheric component but also benefited the oceanic simulation.Hindcast experiments showed that the new scheme remarkably improved both ENSO and IOD prediction skills.The skillful prediction lead time of ENSO was up to 11 months,1 month longer than a hindcast using the original nudging scheme.Skillful prediction of IOD could be made 4–5 months ahead by the new scheme,with a 0.2 higher correlation at a 3-month lead time.These prediction skills approach the level of some of the best state-of-the-art coupled general circulation models.Improved ENSO and IOD predictions occurred across all seasons,but mainly for target months in the boreal spring for the ENSO and the boreal spring and summer for the IOD. | Xunshu Song Xiaojing Li Shouwen Zhang Yi Li Xinrong Chen Youmin Tang Dake Chen | 2022 | Acta Oceanologica Sinica2022，41，2： | 1 |
| 10 | Metabolic engineering of Bacillus amyloliquefaciens for efficient production ofα-glucosidase inhibitor1-deoxynojirimycin显示文摘Owing to the feature of strongα-glucosidase inhibitory activity,1-deoxynojirimycin(1-DNJ)has broad application prospects in areas of functional food,biomedicine,etc.,and this research wants to construct an efficient strain for 1-DNJ production,basing on Bacillus amyloliquefaciens HZ-12.Firstly,using the temperature-sensitive shuttle plasmid T2(2)-Ori,gene ptsG in phosphotransferase system(PTS)was weakened by homologous recombination,and non-PTS pathway was strengthened by deleting its repressor gene iolR,and 1-DNJ yield of resultant strain HZ-S2 was increased by 4.27-fold,reached 110.72 mg/L.Then,to increase precursor fructose-6-phosphate(F-6-P)supply,phosphofructokinase was weaken,fructose phosphatase GlpX and 6-phosphate glucose isomerase Pgi were strengthened by promoter replacement,moreover,regulator gene nanR was deleted,1-DNJ yield was further increased to 267.37 mg/L by 2.41-fold.Subsequently,promoter of 1-DNJ synthetase cluster was optimized,as well as 5′-UTRs of downstream genes in synthetase cluster,and 1-DNJ produced by the final strain reached 478.62 mg/L.Last but not the least,1-DNJ yield of 1632.50 mg/L was attained in 3 L fermenter,which was the highest yield of 1-DNJ reported to date.Taken together,our results demonstrated that metabolic engineering was an effective strategy for 1-DNJ synthesis,this research laid a foundation for industrialization of functional food and drugs based on 1-DNJ. | Xujie Li Meng Zhang Yu Lu Ningyang Wu Jian’gang Chen Zhixia Ji Yangyang Zhan Xin Ma Junyong Chen Dongbo Cai Shouwen Chen | 2023 | Synthetic and Systems Biotechnology2023，8，3： | 0 |
| 11 | Fluorinated poly(ether sulfone) ionomers with disulfonated naphthyl pendants for proton exchange membrane applications显示文摘 | Zhaoxia HU Yao LU Xulve ZHANG Xiaobo YAN Na LI Shouwen CHEN | 2018 | Frontiers of Materials Science2018，12，2： | 0 |
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