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| 1 | V2X Offloading and Resource Allocation in SDN-Assisted MEC-Based Vehicular Networks显示文摘As an important application scenario of 5G, the vehicular network has a huge amount of computing data, which brings challenges to the scarce network resources. Mobile edge computing(MEC) sinks cloud services to the edge of network, which reduces the delay jitter caused by remote cloud computing. Software-defined networking(SDN) is an emerging network paradigm with the features of logic centralized control and programmability. In this paper, we construct an SDN-assisted MEC network architecture for the vehicular network. By introducing SDN controller, the efficiency and flexibility of vehicular network are improved, and the network state can be perceived from the global perspective. To further reduce the system overhead, the problem of vehicle to everything(V2X) offloading and resource allocation is proposed, where the optimal offloading decision, transmission power control, subchannels assignment, and computing resource allocation scheme are given. The optimization problem is transformed into three stages because of the heterogeneity of the offloaded tasks and the NP-hard property of the problem. Firstly, the analytic hierarchy process is used to select initial offloading node, then stateless Q-learning is adopted to allocate transmission power, subchannels and computing resources. In addition, the offloading decision is modeled as a potential game, and the Nash equilibrium is proved by the potential function construction. Finally, the numerical results show that the proposed mechanism can effectively reduce the system overhead and achieve better results compared with others’ algorithms. | Haibo Zhang Zixin Wang Kaijian Liu | 2020 | China Communications2020，17，5： | 12 |
| 2 | Landscape of DILI-related adverse drug reaction in China Mainland显示文摘Drug-induced liver injury(DILI)is a type of bizarre adverse drug reaction(ADR)damaging liver(L-ADR)which may lead to substantial hospitalizations and mortality.Due to the general low incidence,detection of L-ADR remains an unsolved public health challenge.Therefore,we used the data of 6.673 million of ADR reports from January 1st,2012 to December 31st,2016 in China National ADR Monitoring System to establish a new database of L-ADR reports for future investigation.Results showed that totally 114,357 ADR reports were retrieved by keywords searching of liver-related injuries from the original heterogeneous system.By cleaning and standardizing the data fields by the dictionary of synonyms and English translation,we resulted 94,593 ADR records reported to liver injury and then created a new database ready for computer mining.The reporting status of L-ADR showed a persistent 1.62-fold change over the past five years.The national population-adjusted reporting numbers of L-ADR manifested an upward trend with age increasing and more evident in men.The annual reporting rate of L-ADR in age group over 80 years old strikingly exceeded the annual DILI incidence rate in general population,despite known underreporting situation in spontaneous ADR reporting system.The percentage of herbal and traditional medicines(H/TM)L-ADR reports in the whole number was 4.5%,while 80.60%of the H/TM reports were new findings.There was great geographical disparity of reported agents,i.e.more cardiovascular and antineoplastic agents were reported in higher socio-demographic index(SDI)regions and more antimicrobials,especially antitubercular agents,were reported in lower SDI regions.In conclusion,this study presented a large-scale,unbiased,unified,and computer-minable L-ADR database for further investigation.Age-,sex-and SDI-related risks of L-ADR incidence warrant to emphasize the precise pharmacovigilance policies within China or other regions in the world. | Jiabo Wang Haibo Song Feilin Ge Peng Xiong Jing Jing Tingting He Yuming Guo Zhuo Shi Chao Zhou Zixin Han Yanzhong Han Ming Niu Zhaofang Bai Guangbin Luo Chuanyong Shen Xiaohe Xiao | 2022 | Acta Pharmaceutica Sinica B2022，12，12： | 12 |
| 3 | Coupling controls of neotec-tonism and paleoclimate on the Quaternary sediments of the Yangtze (Changjiang) coast显示文摘Attempt has been made to discuss the coupling relation of neotectonism and paleoclimate that have played a critical role in controlling the Quaternary sediment distribu-tion and sedimentary facies evolution on the Yangtze coast. On the basis of petrological analysis, up to six sedimentary cyclicities have been identified in the Quaternary sediment boreholes on the time scale of 0.4―0.5 Ma. The lower sedi-mentary cyclicities (Pliocene to Early Pleistocene) are char-acterized largely by thicker gravelly coarse sands, topped by thinner fine silt and silty clay. Gravels are very angular and clayey gravels prevail. Sediments are usually of poor sorting, rich in log fragments and have no microfossils. Bedload as denoted by C-M plot occurs throughout the section. This evidence represents the alluvial fan sedimentation which took place as the basin began to subside. The middle sedimentary cyclicities (often including Early to Middle Pleistocene) con-sist of basal gravelly sands and clayey silt at the middle and upper sediment sections. Sorting becomes relatively better, and foraminifer appears sporadically. C-M plot reveals the mixture of sediment transport media via bedload, saltation and suspension, representing sedimentation of braided river system at the early stage and subsequently, the sedimentation of meandering river pattern. The upper sedimentary cyclic-ities (including Late Pleistocene to Holocene) comprise basal gravelly sands (exclusive of the Holocene sediment) and thick fine sand and silty clay on the upper section. Sorting becomes fine and foraminifer appears throughout the sediment sec-tion. C-M plot shows that saltation and suspension serve as the main sediment transport media in the sediment section and bedload transport weakens. These evidence the sedi-mentation of meandering river pattern near coast during Late Pleistocene and Holocene time, when marine transgres-sion invaded into the paleoriver valleys, which often forms drowned-valley facies and shallow marine facies. Of note is the Recent delta facies developed on the top of the cyclicities, and characterized by a large proportion of fine sand and siltyclay, and various sedimentary beddings. These phenomena have proved enhanced climate function on sedimentary fa-cies evolution on the basis of previous alluvial fan system, largely affected by tectonic subsidence setting. | WANG Zhangjiao CHEN Zhongyuan WEI Zixin WANG Zhanghua WEI Taoyuan | 2005 | Chinese Science Bulletin2005，50，16： | 10 |
| 4 | MicroTom Metabolic Network: Rewiring Tomato Metabolic Regulatory Network throughout the Growth Cycle显示文摘Tomato(Solanum lycopersicum)is a major horticultural crop worldwide and has emerged as a preeminent model for metabolic research.Although many research efforts have focused on the analysis of metabolite differences between varieties and species,the dynamics of metabolic changes during the tomato growth cycle and the regulatory networks that underlie these changes are poorly understood.In this study,we integrated high-resolution spatio-temporal metabolome and transcriptome data to systematically explore the metabolic landscape across 20 major tomato tissues and growth stages.In the resulting MicroTom Metabolic Network,the 540 detected metabolites and their co-expressed genes could be divided into 10 distinct clusters based on their biological functions.Using this dataset,we constructed a global map of the major metabolic changes that occur throughout the tomato growth cycle and dissected the underlying regulatory network.In addition to verifying previously well-established regulatory networks for important metabolites,we identified novel transcription factors that regulate the biosynthesis of important secondary metabolites such as steroidal glycoalkaloids and flavonoids.Our findings provide insights into spatiotemporal changes in tomato metabolism and generate a valuable resource for the study of metabolic regulatory processes in model plants. | Yan Li Yang Chen Lu Zhou Shengjie You Heng Deng Ya Chen Saleh Alseekh Yong Yuan Rao Fu Zixin Zhang Dan Su Alisdair R.Fernie Mondher Bouzayen Tao Ma Mingchun Liu Yang Zhang | 2020 | Molecular Plant2020，13，8： | 10 |
| 5 | A LuxR family transcriptional regulator AniF promotes the production of anisomycin and its derivatives in Streptomyces hygrospinosus var.beijingensis显示文摘The protein synthesis inhibitor anisomycin features a unique benzylpyrrolidine system and exhibits potent selective activity against pathogenic protozoa and fungi.It is one of the important effective components in Agricultural Antibiotic120,which has been widely used as naturally-originated agents for treatment of crop decay in China.The chemical synthesis of anisomycin has recently been reported,but the complex process with low productivity made the biosynthesis still to be a vital mainstay in efforts.The biosynthetic gene cluster(BGC)of anisomycin in Streptomyces hygrospinosus var.beijingensis has been identified in our previous work,while poor understanding of the regulatory mechanism limited the yield enhancement via regulation engineering of S.hygrospinosus var.beijingensis.In this study here,we characterized AniF as an indispensable LuxR family transcriptional regulator for the activation of anisomycin biosynthesis.The genetic manipulations of aniF and the real-time quantitative PCR(RT-qPCR)revealed that it positively regulated the transcription of the anisomycin BGC.Moreover,the overexpression of aniF contributed to the improvement of the production of anisomycin and its derivatives.Dissection of the mechanism underlying the function of AniF revealed that it directly activated the transcription of the genes aniR-G involved in anisomycin biosynthesis.Especially,one AniF-binding site in the promoter region of aniR was identified by DNase I footprinting assay and an inverted repeat sequence(5′-GGGC-3′)composed of two 4-nt half sites in the protected region was found.Taken together,our systematic study confirmed the positive regulatory role of AniF and might facilitate the future construction of engineering strains with high productivity of anisomycin and its derivatives. | Jufang Shen Lingxin Kong Yan Li Xiaoqing Zheng Qing Wang Weinan Yang Zixin Deng Delin You | 2019 | Synthetic and Systems Biotechnology2019，4，1： | 10 |
| 6 | Qualitative analysis of chemical components in Lianhua Qingwen capsule by HPLC-Q Exactive-Orbitrap-MS coupled with GC-MS显示文摘The Lianhua Qingwen(LHQW) capsule is a popular traditional Chinese medicine for the treatment of viral respiratory diseases.In particular,it has been recently prescribed to treat infections caused by the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2).However,due to its complex composition,little attention has been directed toward the analysis of chemical constituents present in the LHQW capsule.This study presents a reliable and comprehensive approach to characterizing the chemical constituents present in LHQW by high-performance liquid chromatography-Q Exactive-Orbitrap mass spectrometry(HPLC-Q Exactive-Orbitrap-MS) coupled with gas chromatography-mass spectrometry(GC-MS).An automated library alignment method with a high mass accuracy(within 5 ppm) was used for the rapid identification of compounds.A total of 104 compounds,consisting of alkaloids,flavonoids,phenols,phenolic acids,phenylpropanoids,quinones,terpenoids,and other phytochemicals,were successfully characterized.In addition,the fragmentation pathways and characteristic fragments of some representative compounds were elucidated.GC-MS analysis was conducted to characterize the volatile compounds present in LHQW.In total,17 compounds were putatively characterized by comparing the acquired data with that from the NIST library.The major constituent was menthol,and all the other compounds were terpenoids.This is the first comprehensive report on the identification of the major chemical constituents present in the LHQW capsule by HPLC-Q Exactive-Orbitrap-MS,coupled with GCMS,and the results of this study can be used for the quality control and standardization of LHQW capsules. | Shuai Fu Rongrong Cheng Zixin Deng Tiangang Liu | 2021 | Journal of Pharmaceutical Analysis2021，11，6： | 8 |
| 7 | Structural insights into DndE from Escherichia coil B7A involved in DNA phosphorothioation modification显示文摘 | Wei Hu Chengkun Wang Jingdan Liang Tianlong Zhang Zhongpei Hu Zhijun Wang Wenxian Lan Fang Li Houming Wu Jianping Ding Geng Wu Zixin Deng Chunyang Cao | 2012 | Cell Research2012，22，7： | 7 |
| 8 | Clinical features and the traditional Chinese medicine therapeutic characteristics of 293 COVID-19 inpatient cases显示文摘Coronavirus disease 2019 (COVID-19) is now pandemic worldwide and has heavily overloaded hospitals in Wuhan City, China during the time between late January and February. We reported the clinical features and therapeutic characteristics of moderate COVID-19 cases in Wuhan that were treated via the integration of traditional Chinese medicine (TCM) and Western medicine. We collected electronic medical record (EMR) data, which included the full clinical profiles of patients, from a designated TCM hospital in Wuhan. The structured data of symptoms and drugs from admission notes were obtained through an information extraction process. Other key clinical entities were also confirmed and normalized to obtain information on the diagnosis, clinical treatments, laboratory tests, and outcomes of the patients. A total of 293 COVID-19 inpatient cases, including 207 moderate and 86 (29.3%) severe cases, were included in our research. Among these cases, 238 were discharged, 31 were transferred, and 24 (all severe cases) died in the hospital. Our COVID-19 cases involved elderly patients with advanced ages (57 years on average) and high comorbidity rates (61%). Our results reconfirmed several well-recognized risk factors, such as age, gender (male), and comorbidities, as well as provided novel laboratory indications (e.g., cholesterol) and TCM-specific phenotype markers (e.g., dull tongue) that were relevant to COVID-19 infections and prognosis. In addition to antiviral/antibiotics and standard supportive therapies, TCM herbal prescriptions incorporating 290 distinct herbs were used in 273 (93%) cases. The cases that received TCM treatment had lower death rates than those that did not receive TCM treatment (17/273= 6.2% vs. 7/20= 35%, P = 0.0004 for all cases;17/77= 22% vs. 7/9= 77.7%, P = 0.002 for severe cases). The TCM herbal prescriptions used for the treatment of COVID-19 infections mainly consisted of Pericarpium Citri Reticulatae, Radix Scutellariae, Rhizoma Pinellia, and their combinations, which reflected the practical TCM principles (e.g., clearing heat and dampening phlegm). Lastly, 59% of the patients received treatment, including antiviral, antibiotics, and Chinese patent medicine, before admission. This situation might have some effects on symptoms, such as fever and dry cough. By using EMR data, we described the clinical features and therapeutic characteristics of 293 COVID-19 cases treated via the integration of TCM herbal prescriptions and Western medicine. Clinical manifestations and treatments before admission and in the hospital were investigated. Our results preliminarily showed the potential effectiveness of TCM herbal prescriptions and their regularities in COVID-19 treatment. | Zixin Shu Yana Zhou Kai Chang Jifen Liu Xiaojun Min Qing Zhang Jing Sun Yajuan Xiong Qunsheng Zou Qiguang Zheng Jinghui Ji Josiah Poon Baoyan Liu Xuezhong Zhou Xiaodong Li | 2020 | Frontiers of Medicine2020，14，6： | 7 |
| 9 | Simulation of regional land subsidence in the southern Yangtze Delta显示文摘Investigation of the deformation characteristics of individual hydrostratigraphic units is the key to construct a regional land subsidence model. All of 12 hydrostratigraphic units in the study area were discussed throughout. On the basis of the measured data of groundwater level, five kinds of changing patterns of groundwater level were deduced and the relationship between the deformation characteris-tics of aquifer units and the corresponding changing patterns of groundwater level was discussed. The study area is 1.7×104 km2, where the geological condition is complex. The changing patterns of groundwater level the hydrostratigraphic units have experienced vary from site to site and from time to time. Consequently, the deformation characteristics of units are sophisticated. An identical hydros-tratigraphic unit may exhibit different deformation characteristics, such as elasticity, elasto-plasticity, visco-elasticity, and visco-elasto-plasticity, at different sites or during different periods, not to mention the different units. The existing models are difficult to describe the complex visco-elasto-plastic con-stitutive law under the condition of land subsidence. So the Merchant’s model was modified to depict the visco-elasto-plastic behavior of units. Then a three-dimensional flow model with variable parame-ters and a vertical one-dimensional subsidence model were constructed and coupled. The coupled model was applied in simulating land subsidence in the southern Yangtze Delta and a satisfactory re-sult was obtained. The simulation results show that the new coupled model can depict the complex geological conditions and describe the developing process of land subsidence very well in the south-ern Yangtze Delta. The new model can surely be used to predict land subsidence in the future, which is very helpful to taking measurements to control land subsidence. | XUE YuQun WU JiChun ZHANG Yun YE ShuJun SHI XiaoQing WEI ZiXin LI QinFen YU Jun | 2008 | Science China Earth Sciences2008，51，6： | 6 |
| 10 | Heterologous expression of Avermectins biosynthetic gene cluster by construction of a Bacterial Artificial Chromosome library of the producers显示文摘Avermectins,a group of polyketide natural products,are widely used as anthelmintics in agriculture.Metabolic engineering and combinatorial biosynthesis were extensively employed to improve Avermectins production and create novel Avermectin derivatives,including Ivermectin and Doramectin.It is labor intensive and time cost to genetically manipulate Avermectins producer Streptomyces avermitilis in vivo.Cloning and heterologous expression of Avermectins biosynthetic gene cluster will make it possible to tailor the cluster in vitro.We constructed a Bacterial Artificial Chromosome(BAC)library of S.avermitilis ATCC 31267 with inserted DNA fragments ranged from 100 to 130 Kb.Five recombinant BAC clones which carried the Avermectins biosynthetic gene cluster ave(81 Kb in size)were screened out from the library.Then,ave was hetero-expressed in S.lividans.Three Avermectin components,A2a,B1a and A1a were detected from the cell extracts of recombinant strains.It will facilitate the development of Avermectin derivatives by polyketide synthase domain swapping and provide functional element for Avermectins synthetic biology study. | Qian Deng Li Zhou Meizhong Luo Zixin Deng Changming Zhao | 2017 | Synthetic and Systems Biotechnology2017，2，1： | 5 |
| 11 | Quantitative method for evaluating detailed volatility of wind power at multiple temporal-spatial scales显示文摘With the increasing proportion of wind power integration, the volatility of wind power brings huge challenges to the safe and stable operation of the electric power system. At present, the indexes commonly used to evaluate the volatility of wind power only consider its overall characteristics, such as the standard deviation of wind power, the average of power variables, etc., while ignoring the detailed volatility of wind power, that is, the features of the frequency distribution of power variables. However, how to accurately describe the detailed volatility of wind power is the key foundation to reduce its adverse influences. To address this, a quantitative method for evaluating the detailed volatility of wind power at multiple temporal-spatial scales is proposed. First, the volatility indexes which can evaluate the detailed fluctuation characteristics of wind power are presented, including the upper confidence limit, lower confidence limit and confidence interval of power variables under the certain confidence level. Then, the actual wind power data from a location in northern China is used to illustrate the application of the proposed indexes at multiple temporal(year–season–month–day) and spatial scales(wind turbine–wind turbines–wind farm–wind farms) using the calculation time windows of 10 min, 30 min, 1 h, and 4 h. Finally, the relationships between wind power forecasting accuracy and its corresponding detailed volatility are analyzed to further verify the effectiveness of the proposed indexes. The results show that the proposed volatility indexes can effectively characterize the detailed fluctuations of wind power at multiple temporal-spatial scales. It is anticipated that the results of this study will serve as an important reference for the reserve capacity planning and optimization dispatch in the electric power system which with a high proportion of renewable energy. | Yongqian Liu Han Wang Shuang Han Jie Yan Li Li Zixin Chen | 2019 | Global Energy Interconnection2019，2，4： | 5 |
| 12 | Rational design for fungal laccase production in the model host Aspergillus nidulans显示文摘Laccases, multicopper oxidoreductases, are mainly produced in white-rot fungi and are considered as ideal green catalysts in industrial and biotechnological applications. However, the development of laccases is limited due to the slow growth of natural laccase producing strains and the low expression levels of laccases. In this study, we designed three regulation strategies for laccase gene expression in the model fungus Aspergillus nidulans. By introducing various promoters in front of the laccase gene pslcc from the white-rot fungus Pycnoporus sanguineus, we found that the laccase gene with the original promoter had effective expression in A. nidulans. Using the previously identified transcription factor RsmA regulatory mechanism, the aflR promoter was inserted into the pslcc expression vectors, and the laccase production was 15-fold higher in the strain overexpressing of RsmA compared to the control strain. To improve the laccase yield, the dipeptidyl-peptidase DppV, aspartic protease PepA and mannosyltransferase Mnn9 were successfully deleted in the A. nidulans host. The laccase activities were increased approximately 8-fold and 13-fold in the double deletions strains of Δmnn9ΔpepA and ΔdppVΔpepA over the control strains, respectively.Taken together, these results not only demonstrate an efficient system for heterologous protein production in the model fungus A.nidulans but also provide a general approach to applying regulatory methods to control gene expression. | Wei Li Jingwen Yu Zixin Li Wen-Bing Yin | 2019 | Science China(Life Sciences)2019，62，1： | 5 |
| 13 | Super enhancer inhibitors suppress MYC driven transcriptional amplification and tumor progression in osteosarcoma显示文摘Osteosarcoma is the most common primary bone sarcoma that mostly occurs in young adults. The causes of osteosarcoma are heterogeneous and still not fully understood. Identification of novel, important oncogenic factors in osteosarcoma and development of better, effective therapeutic approaches are in urgent need for better treatment of osteosarcoma patients. In this study, we uncovered that the oncogene MYC is significantly upregulated in metastastic osteosarcoma samples. In addition, high MYC expression is associated with poor survival of osteosarcoma patients. Analysis of MYC targets in osteosarcoma revealed that most of the osteosarcoma super enhancer genes are bound by MYC. Treatment of osteosarcoma cells with super enhancer inhibitors THZ1 and JQ1 effectively suppresses the proliferation, migration, and invasion of osteosarcoma cells. Mechanistically,THZ1 treatment suppresses a large group of super enhancer containing MYC target genes including CDK6 and TGFB2. These findings revealed that the MYC-driven super enhancer signaling is crucial for the osteosarcoma tumorigenesis and targeting the MYC/super enhancer axis represents as a promising therapeutic strategy for treatment of osteosarcoma patients. | Demeng Chen Zhiqiang Zhao Zixin Huang Du-Chu Chen Xin-Xing Zhu Yi-Ze Wang Ya-Wei Yan Shaojun Tang Subha Madhavan Weiyi Ni Zhan-peng Huang Wen Li Weidong Ji Huangxuan Shen Shuibin Lin Yi-Zhou Jiang | 2018 | Bone Research2018，6，2： | 5 |
| 14 | UNBALANCE RESPONSE AND TOUCH-RUBBING THRESHOLD SPEED OF ROTOR SUBJECTED TO NONLINEAR MAGNETIC FORCES显示文摘Because of the effect of unbalance excitation and nonlinear magnetic force,the large vibration of the rotor supported by active magnetic bearing(AMB) will go beyond the radial gap of the beating,even causing mechanical touch-rubbing when the system works at an operational speed closer to the critical speed.In order to investigate this problem,the linear model and nonlinear model of the single mass symmetric rigid rotor system supported by AMB are established respectively and the corresponding transfer functions of close-loop system are given.To pass through the numerical calculation by using MATLAB/Simulink,the effect of both the unbalance response and threshold speed of touch-rubbing of the system subjected to nonlinear magnetic forces and nonlinear output current of power amplifier are studied.Furthermore,threshold speed of touch-rubbing of the rotor-bearing system is defined and the results of numerical simulation are presented.Finally,based on above studies,two methods of increasing the touch-rubbing threshold speed are discussed. | JING Minqing LI Zixin LUO Min YU Lie | 2008 | Chinese Journal of Mechanical Engineering2008，21，2： | 5 |
| 15 | Inactivation of the positive LuxR-type oligomycin biosynthesis regulators OlmRI and OlmRII increases avermectin production in Streptomyces avermitilis显示文摘Oligomycins are a group of 26 macrocyclic lactones that exhibit broad biological activities,including antifungal,anticancer and nematocidal activities.Analysis of the oligomycin biosynthetic gene cluster (olm) in S.avermitilis revealed 2 tandem LuxR-type regulators,OlmRI (931 aa) and OlmRII (941 aa),with shared identity of 38%.Gene replacement of olmRI or olmRII abolished oligomycin production,and this production could be partially restored in the disruptants by introducing cloned olmRI and olmRII with their native promoters,demonstrating the essential role of OlmRI and OlmRII for oligomycin biosynthesis.Quantitative real-time RT-PCR analysis revealed that transcription of 14 olm genes was differentially affected by the deletion of olmRI and olmRII.Unexpectedly,avermectin production in both mutants was enhanced at least 4-fold.The identification of the positive cluster-situated regulators,OlmRI and OlmRII,paves the way for the transcriptional analysis of oligomycin biosynthesis and for the enhancement of oligomycin and avermectin production through regulator engineering. | YU Qing BAI LinQuan ZHOU XiuFen DENG ZiXin | 2012 | Chinese Science Bulletin2012，57，8： | 4 |
| 16 | Asm8, a specific LAL-type activator of 3-amino-5-hydroxy-benzoate biosynthesis in ansamitocin production显示文摘The highly potent antitumor agent ansamitocin P3 is a macrolactam isolated from Actinosynnema pretiosum ATCC 31565. A 120-kb DNA fragment was previously identified as the ansamitocin biosynthetic gene cluster, and contains genes for polyketide assembly, precursor synthesis, post-polyketide synthesis modification, and regulation. Within the biosynthetic gene cluster, asm8 encodes an 1117-amino-acid protein with a high degree of similarity to the large ATP-binding LuxR family-type regulators. In the current study, we determined that inactivation of asm8 by gene replacement in ATCC 31565 resulted in the complete loss of ansamitocin production, and that complementation with a cloned asm8 gene restored ansamitocin biosynthesis. Interestingly, the disruption of asm8 decreased the transcription of genes responsible for 3-amino-5-hydroxybenzoate (AHBA) formation, the starter unit required for ansamitocin biosynthesis. Subsequently, feeding of exogenous AHBA to the asm8 mutant restored ansamitocin biosynthesis, which showed that Asm8 is a specific positive regulator in AHBA biosynthesis. In addition, investigation of asm8 homologs identified two new ansamitocin producers, and inactivation of the asm8 homolog in A. pretiosum ATCC 31280 abolished ansamitocin production in this strain. Characterization of the positive regulator Asm8 and discovery of the two new ansamitocin producers paves the way for further improving production of this important antitumor agent. | PAN WenQin KANG QianJin WANG Lei BAI LinQuan DENG ZiXin | 2013 | Science China(Life Sciences)2013，56，7： | 4 |
| 17 | Characterization of the positive SARP family regulator PieR for improving piericidin A1 production in Streptomyces piomogeues var.Hangzhouwanensis显示文摘Piericidin A1,a member ofɑ-pyridone antibiotic,exhibits various biological activities such as antimicrobial,antifungal,and antitumor properties and possesses potent respiration-inhibitory activity against insects due to its competitive binding capacity to mitochondrial complex I.The biosynthetic pathway of piericidin A1 has been reported in Streptomyces piomogeues var.Hangzhouwanensis,while the regulatory mechanism remains poorly understood.In this study,a Streptomyces antibiotic regulatory protein(SARP)family transcriptional regulator PieR was characterized.Genetic disruption and complementation manipulations revealed that PieR positively regulated the production of piericidin A1.Moreover,the overexpression of pieR contributed to the improvement of piericidin A1 productivity.The real-time quantitative PCR(RT-qPCR)was carried out and the data showed that pieR stimulated the transcription of all the biosynthesis-related genes for piericidin A1.In order to explore the regulatory mechanism,electrophoresis mobility shift assays(EMSA)and DNase I footprinting experiments have been conducted.A protected region covering 50 nucleotides within the upstream region of pieR was identified and two 5-nt direct repeat sequences(5′-CCGGA-3′)in the protected region were found.These findings,taken together,set stage for transcriptional control engineering in the view of optimizing piericidin A1 production and thus provide a viable potent route for the construction of strains with high productivity. | Yan Li Lingxin Kong Jufang Shen Qing Wang Qian Liu Weinan Yang Zixin Deng Delin You | 2019 | Synthetic and Systems Biotechnology2019，4，1： | 4 |
| 18 | Streptomyces avermitilis industrial strain as cell factory for Ivermectin B1a production显示文摘Ivermectin,a kind of valuable derivatives of Avermectin,is distinct from Avermectin due to the saturated bond at C22eC23 position.Combinatorial biosynthesis of Ivermectins based on Avermectins biosynthetic gene cluster(ave)has been achieved recently,while the establishment of an Ivermectin homogeneous component producing strain is challenging because of the limited compatibility between the native and heterologous polyketide synthase(PKS)domains.In this study,the PKS module 2 Dehydratase(DH)-Enoylreductase(ER)-Ketoreductase(KR)domain set of Meilingmycin,which is another naturally occurring homologue of Avermectin,was employed to substitute the DH-KR domains of Avermectins PKS module 2 to generate an Ivermectin biosynthetic gene cluster(ive).Ivermectins B1a and A1a were heterologously biosynthesized in a classic actinomyces host Streptomyces lividans.The Avermectin B1a high-producing strain S.avermitilis 3-115 was genetically engineered to give an artificial host cell and Ivermectin B1a single component was effectively produced with a production of 1.25±0.14 g/L. | Qian Deng Liqiongzi Xiao Yang Liu Lixin Zhang Zixin Deng Changming Zhao | 2019 | Synthetic and Systems Biotechnology2019，4，1： | 3 |
| 19 | Mesozoic–Cenozoic Tectonic Evolution and Uplift in Pamir:Application of Fission Track Thermochronology显示文摘The Pamir Plateau can be divided into three secondary tectonic units from north to south:the North,the Middle and the South Pamir Blocks.The North Pamir Block belonged to the southern margin of Tarim-Karakum,thermochronological study of the Pamir structural intersection indicates that accretion of the Middle Pamir Block to the Eurasian Continental Margin and its subduction and collision with the North Pamir Block occurred in the Middle–Late Jurassic.Due to the Neo-Tethys closure in the Early Cretaceous,the South Pamir Block began to collide with the accretion(the Middle Pamir Block)of the Eurasian Continental Margin.Affected by the collision and continuous convergence between the Indian Plate and the Eurasian Plate since the Cenozoic,Pamir is in a multi-stage differential uplift process.During 56.1–48.5 Ma,North Pamir took the lead in uplifting,that is,the first rapid uplift in the Pamir region began there.The continuous compression and contraction of the Indian and Eurasian plates during 22.0–15.1 Ma forced the Pamir tectonic syntaxis to begin its overall uplift,i.e.Pamir began to enter the second rapid uplift stage in the Early Oligocene,which lasted until the Middle Miocene.During 14.6–8.5Ma,South Pamir was in a rapid uplift stage,while North Pamir was in a relatively stable state,showing asymmetry of tectonic deformation in the Pamir region in space.Since 6.5 Ma,Pamir began to rapidly uplift again. | FAN Baocheng LIU Mingyi HE Zixin MENG Guanglu WU Huanhuan LI Lu | 2021 | Acta Geologica Sinica(English Edition)2021，95，3： | 3 |
| 20 | Analysis and prediction of loudspeaker large-signal symptoms显示文摘Nonlinear lumped-parameter force factor Bl(x), stiffness Kms(x) and inductance Le(x) of electrodynamic loudspeakers change frequency responses and generate some nonlinear effects for large stimulus: harmonic and intermodulation distortion, DC component in diaphragm displacement, instability of vibration and jumping effects. By modeling the nonlinear system under large-signal conditions, relationship between the nonlinear parameters and large-signal behavior can be revealed and help to provide guidance to diagnose loudspeakers. Agreement between the measured and predicted responses of a real loudspeaker validates the modeling and enables new methods for loudspeaker diagnosis. | HENG Wei SHEN Yong XIA Jie FENG ZiXin LIU YunFeng | 2013 | Science China(Physics,Mechanics & Astronomy)2013，56，7： | 3 |
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