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Characterization of a novel regulatory pathway for mannitol metabolism and its coordination with biofilm formation in Mycobacterium smegmatis

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Journal of Genetics and Genomics 2018年第9期45卷 477-488页

作者： Jialing Hu hua Zhang Si zhou Weihui Li zheng-Guo He National Key Laboratory of Agricultural Microbiology College of Life Science and TechnologyHuazhong Agricultural University

Biofilm formation has been implicated to be tightly regulated in bacteria. Mycobacterial species possess a unique cell-wall structure; however, the underlying regulation mechanism for their biofilm formation remains largely unclear. In this study, we characterized a hypothetical mannitol metabolism and transportation gene cluster（Ms5571-Ms5576）, designated as mmt operon, whose expression significantly contributes to the biofilm formation in Mycobacterium smegmatis. We showed that in the operon the Ms5575 gene encodes a GntR-like transcriptional repressor and the Ms5576 gene encodes a mannitol2-dehydrogenase which can produce D-mannitol from D-mannose. Strikingly, the D-mannitol molecule can derepress the negative regulation of Ms5575 on the mmt operon to stimulate the operon＇s expression. Consistently, addition of D-mannitol into the medium can obviously induce mycobacterial biofilm formation. Furthermore, we found that Ms0179 positively regulates the mmt operon through its downstream regulator Ms0180. Ms0180 directly binds the mmt operon to positively regulate its expression. Both Ms0179 and Ms0180 significantly affect the mycobacterial biofilm formation. Taken together, we explored a regulatory pathway for the mannitol metabolism and its coordination with the biofilm formation in M. smegmatis. This finding provides novel insights into the unique mechanism of biofilm formation regulation in mycobacteria.

关键词： Transcription regulation Biofilm formation Mannitol Mycobacteria

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Why over-parameterization of deep neural networks does not overfit?

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Science China(Information Sciences) 2021年第1期64卷 242-244页

作者： Zhi-hua zhou National Key Laboratory for Novel Software Technology Nanjing University

Deep neural networks often come with a huge number of parameters,even larger than the number of training examples,but it seems that these over-parameterized models have not suffered from *** is quite strange and why over-parameterization does not overfit?poses a fundamental question concerning the mysteries behind the success of deep neural networks.

关键词： Information Systems and Communication Service

Effect of altitude and climatic parameters on shrub-meadow community composition and diversity in the dry valley region of the eastern Hengduan Mountains,China

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Journal of Mountain Science 2022年第4期19卷 1139-1155页

作者： ZONG hua SUN Jia-rui zhou Lu BAO Fang zheng Xian-zhu Department of Landscape College of ArchitectureSouthwest Jiaotong UniversityChengdu 11756China China Railway Eryuan Engineering Group Co.LTD Chengdu 610031China

Because of the“foehn effect”,deeply incised gorges of major rivers in the Hengduan Mountains(commonly called dry valleys)have semiarid or arid *** environment and difficult access have so far obstructed the systematic inventory and documentation of the flora of these dry *** is particularly problematic for efforts towards the conservation of endemic and valuable plant ***,102 shrub-meadow community survey plots were set up along four dry valleys in Ganzi prefecture,located in the eastern Hengduan Mountains,*** compositions,richness,diversity of these communities were calculated and assessed using sample plot survey and phytosociological ***,244 plant species were recorded,consisting of subtropical(48.77%)and temperate(38.83%)species,47.13%of which were endemic to southwest *** differences in species composition and structure along the altitude gradient were *** variations of richness,diversity,and evenness followed a bimodal-hump shaped pattern with increasing altitude,with peak occurring at mid-level altitude(3501–4000 m)and valley occurring at 2501–3000 m *** regions at 2501–3000 m altitudes were more sensitive to global climate change and biological interference,and were found to have the highest protection *** impacts of altitude gradients and climatic parameters on the features of this shrubmeadow community were also evaluated using principal component and multiple linear stepwise regression analysis *** and temperature-related variables were the most important drivers of both species richness and ***α-diversity here only depended on the precipitation *** founding could help to understand the impact of the very harsh environment and altitude gradient on plant-plant interactions in a variety of natural systems.

关键词： Dry valley Shrub meadow community Composition Diversity Altitude Climatic parameters

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Wet synthesis endows scalable epitaxy of complex oxide multiferroics

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National Science Review 2020年第7期7卷 1147-1148页

作者： hua zhou X-ray Science Division Advanced Photon SourceArgonne National Laboratory

Synthesis is the bridge linking scientific fantasies to practical realizations, to push the boundaries of materials exploration with societally impactful applications. As one of the most promising classes of materials with direct technological implications, complex oxides exhibit an amazing collection of electronic, chemical,ionic and topological properties, making them strategic candidates for a variety of electronic, energy and environ-

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Flow units as dynamic defects in metallic glassy materials

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National Science Review 2019年第2期6卷 304-323页

作者： zheng Wang Wei-hua Wang Institute of Physics Chinese Academy of Sciences

In a crystalline material, structural defects such as dislocations or twins are well defined and largely determine the mechanical and other properties of the material. For metallic glass(MG) with unique properties in the absence of a long-range lattice, intensive efforts have focused on the search for similar 'defects'. The primary objective has been the elucidation of the flow mechanism of MGs. However,their atomistic mechanism of mechanical deformation and atomic flow response to stress, temperature, and failure, have proven to be challenging. In this paper, we briefly review the state-of-the-art studies on the dynamic defects in metallic glasses from the perspective of flow units. The characteristics, activation and evolution processes of flow units as well as their correlation with mechanical properties, including plasticity,strength, fracture, and dynamic relaxation, are introduced. We show that flow units that are similar to structural defects such as dislocations are crucial in the optimization and design of metallic glassy materials via the thermal, mechanical and high-pressure tailoring of these units. In this report, the relevant issues and open questions with regard to the flow unit model are also introduced and discussed.

关键词： metallic glass flow unit flow glass transition mechanical deformation property optimization

Effect of femtosecond and microkeratome flaps creation on the cornea biomechanics during laser in situ keratomileusis： one year follow-up

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International Journal of Ophthalmology(English edition) 2016年第10期9卷 1409-1414页

作者： Qian Sun zheng-zheng Deng Yue-hua zhou Jing Zhang Xiao-Yan Peng Ophthalmic Center Beijing Tongren Hospital Capital Medical University Beijing Ophthalmology & Visual Sciences Key Lab Beijing 100730 China Mingren Hospital Handan 05000 Hebei Province China

AIM： To compare the corneal biomechanical outcomes at one year after laser in situ keratomileusis（LASIK） with the flaps created by Ziemer and Moria M2 microkeratome with 110 head and -20 ***： Totally 100 eyes of 50 consecutive patients were enrolled in this prospective study and divided into two groups for corneal flaps created by Ziemer Femto LDV and Moria M2 microkeratome with 110 head and -20 *** biomechanical properties including cornea resistance factor（CRF） and cornea hysteresis（CH） were measured before and 1,3,6,12 mo after surgery by ocular response *** cornea thickness and corneal flap thickness were measured by optical coherence ***： The ablation depth（P=0.693）,residual corneal thickness（P=0.453）,and postoperative corneal curvature（P=0.264） were not significant different between Ziemer group and Moria 110-20 group after *** residual stromal bed thickness,corneal flap thickness,CH and CRF at 12 mo after surgery were significant different between Ziemer group and Moria 110-20 group（P〈0.01）; Ziemer group gained better corneal biomechanical *** CRF and CH increased gradually from 1 to12 mo after surgery in Ziemer group,increased from 1 to 6 mo but decreased from 6 to 12 mo in Moria 110-20 *** CRF and CH at one year after surgery increased with the increasing of residual cornea thickness; pre-LASIK CRF,CRF also increased with residual stromal bed thickness,while CH decreased with the increasing of pre-LASIK intraocular pressure and cornea flap thickness（P〈0.01）.CONCLUSION： In one year follow-up,femtosecond laser can provide better cornea flaps with stable cornea biomechanics than mechanical microkeratome.

关键词： femtosecond microkeratome biomechanics keratomileusis

Floquet control of the gain and loss in a PT-symmetric optical coupler

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Frontiers of physics 2017年第1期12卷 99-105页

作者： Yi Wu Bo Zhu Shu-Fang Hu zheng zhou Hong-hua Zhong Department of Physics Engineering University of CAPF Xi'an 710086 China School of Physics and Astronomy Sun Yat-Sen University (Zhuhai Campus) Zhuhai 519082China Institute of Mathematics and Physics Central South University of Forestry and Technology Changsha 410004 China Department of Physics Hunan Institute of Technology Hengyang 421002 China

Controlling the balanced gain and loss in a PT-symmetric system is a rather challenging task. Utilizing Floquet theory, we explore the constructive role of periodic modulation in controlling the gain and loss of a PT-symmetric optical coupler. It is found that the gain and loss of the system can be manipulated by applying a periodic modulation. Purther, such an original non-Hermitian system can even be modulated into an effective Hermitian system derived by the high-frequency Floquet method. Therefore, compared with other PT- symmetry control schemes, our protocol can modulate the unbroken PT-symmetric range to a wider parameter region. Our results provide a promising approach for controlling the gain and loss of a realistic system.

关键词： PT- symmetry periodic modulation optical coupler

Conditioning treatments mitigate the levels of fecal pollution indicators in soil during land-application of sewage sludge

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Science China(Technological Sciences) 2024年第10期67卷 3091-3102页

作者： WANG YuHang LI hua FANG WenHao WANG Ru WANG XinXin zheng GuanYu zhou LiXiang Department of Environmental Engineering College of Resources and Environmental SciencesNanjing Agricultural UniversityNanjing 210095China College of Materials and Chemical Engineering Pingxiang UniversityPingxiang 337055China Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization Nanjing 210095China

Sewage sludge is a major source of fecal pathogens in the environment,and its application to land can result in a significant release of these pathogens into the *** conditioning treatments are crucial for improving the dewatering process of sludge,their impact on the presence and behavior of fecal pathogens in soil remains *** study aims to assess four extraction methods for recovering fecal pollution indicators from soil amended with unconditioned and conditioned *** indicators include Escherichia coli(EC),human-specific HF183 Bacteroides(HF183),human adenovirus(HAdV),human BK polyomavirus(BKPyV),human JC polyomavirus(JCPyV),and cross-assembly phage(crAssphage).This study also examines how soil moisture content affects the decay of these fecal pollution indicators in soil amended with raw sludge and investigates the influence of conditioning treatments with cationic polyacrylamide(PAM),Fenton’s reagents,Fe[III]/CaO on their persistence in *** results indicated that the direct extraction method was the most effective and unbiased for recovering fecal pollution indicators from sludge-amended soil compared with the three elution-concentration *** fecal pollution indicators,except HAdV,remained stable under dry soil conditions,while high soil moisture content(48.39%‒53.14%)slowed the decay rates of these *** the application of sludge to soil,effective control of fecal pollution indicators was observed,with JCPyV and HAdV becoming undetectable within a short *** log reduction values of HF183,BKPyV,and crAssphage ranged from 0.1 to 2.8 logs after 30 d of *** application of conditioned sludge,especially Fenton’s reagent-conditioned sludge,resulted in a reduction in human fecal contamination in the receiving ***,implementing appropriate conditioning methods,such as using Fenton’s reagent,can effectively mitigate the health risks associated with fecal pathogens.

关键词： fecal pollution indicators sewage sludge conditioning treatment land application soil

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Red cell distribution width/platelet ratio predicts decompensation of metabolic dysfunction-associated steatotic liver disease-related compensated advanced chronic liver disease

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World Journal of Gastroenterology 2025年第3期31卷 1-10页

作者： Ming-hua zheng Amedeo Lonardo Department of Hepatology MAFLD Research CenterThe First Affiliated Hospital of Wenzhou Medical UniversityWenzhou 325000Zhejiang ProvinceChina Department of Internal Medicine Azienda Ospedaliero-Universitaria of Modena(2023)Modena 41126Italy

Prognostication of compensated advanced chronic liver disease(cACLD)is of paramount importance for the physician-and-patient communication and for rational clinical *** paper published by Dallio et al reports on red cell distribution width(RDW)/platelet ratio(RPR)as a non-invasive biomarker in predicting decompensation of metabolic dysfunction-associated steatotic liver disease(MASLD)-related *** from other biomarkers and algorithms,RPR is inexpensive and widely available,based on parameters which are included in a complete blood *** is computed on the grounds of two different items,one of which,RDW,mirrors the host’s response to a variety of disease stimuli and is *** second parameter involved in RPR,platelet count,is more specific and has been used in the hepatological clinic to discriminate cirrhotic from non-cirrhotic chronic liver disease for *** disease is the primary cause of mortality among MASLD subjects,followed by extra-hepatic cancers and liver-related ***,MASLD biomarkers should be validated not only in terms of liver-related events but also in the prediction of major adverse cardiovascular events and cardiovascular mortality and extra-hepatic *** sized multi-ethnic confirmatory investigation is required to define the role and significance of RPR in the stratification of MASLD-cACLD.

关键词： Cirrhosis Liver fibrosis Natural course Prognostication Stratification