检索结果-南通市图书馆

Tsinghua Science and Technology 2024年第2期29卷 386-399页

作者： Jingfang Chen Ling Wang Zixiao Pan yuting Wu Jie zheng Xuetao Ding Department of Automation Tsinghua UniversityBeijing 100084China Department of Delivery Technology MeituanBeijing 100102China

The on-demand food delivery(OFD)service has gained rapid development in the past decades but meanwhile encounters challenges for further improving operation quality.The order dispatching problem is one of the most concerning issues for the OFD platforms,which refer to dynamically dispatching a large number of orders to riders reasonably in very limited decision time.To solve such a challenging combinatorial optimization problem,an effective matching algorithm is proposed by fusing the reinforcement learning technique and the optimization method.First,to deal with the large-scale complexity,a decoupling method is designed by reducing the matching space between new orders and riders.Second,to overcome the high dynamism and satisfy the stringent requirements on decision time,a reinforcement learning based dispatching heuristic is presented.To be specific,a sequence-to-sequence neural network is constructed based on the problem characteristic to generate an order priority sequence.Besides,a training approach is specially designed to improve learning performance.Furthermore,a greedy heuristic is employed to effectively dispatch new orders according to the order priority sequence.On real-world datasets,numerical experiments are conducted to validate the effectiveness of the proposed algorithm.Statistical results show that the proposed algorithm can effectively solve the problem by improving delivery efficiency and maintaining customer satisfaction.

关键词： order dispatching on-demand delivery reinforcement learning decoupling strategy sequence-to-sequence neural network

Effect of exogenous flavins on the microbial corrosion by Geobacter sulfurreducens via iron-to-microbe electron transfer

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2024年第4期171卷 129-138页

作者： yuting Jin Jiaqi Li Mingxing Zhang Borui zheng Dake Xu Tingyue Gu Fuhui Wang Shenyang National Laboratory for Materials Science Northeastern UniversityShenyang 110819China Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) Northeastern UniversityShenyang 110819China Department of Chemical and Biomolecular Engineering Institute for Corrosion and Multiphase TechnologyOhio UniversityAthens OH 45701USA

Microbes can cause or accelerate metal corrosion,leading to huge losses in corrosion damages each year.Geobacter sulfurreducens is a representative electroactive bacterium in many soils,sediments,and wastew-ater systems.It has been confirmed to directly extract electrons from elemental metals.However,little is known about the effect of electron shuttles in G.sulfurreducens corrosion on stainless steel.In this study,we report that exogenous flavins promote iron-to-microbe electron transfer,accelerating micro-bial corrosion.G.sulfurreducens caused 1.3 times deeper pits and increased electron uptake(with 2 times increase of i_(corr))from stainless steel when riboflavin was added to the culture medium.OmcS-deficient mutant data suggest that G.sulfurreducens utilizes riboflavin as a bound-cofactor in outer membrane c-type cytochromes.The finding that,in the presence of microbes,riboflavin can substantially accelerate corrosion highlights the role of flavin redox cycling for enhanced iron-to-microbe electron transfer by G.sulfurreducens and provides new insights in microbial corrosion.

关键词： Extracellular electron transfer Microbiological corrosion Geobacter sulfurreducens Outer membrane c-type cytochromes Exogenous flavins

Molecular design of an ultra-strong tissue adhesive hydrogel with tunable multifunctionality

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Bioactive Materials 2023年第11期29卷 214-229页

作者： yuting zheng Avijit Baidya Nasim Annabi Department of Chemical and Biomolecular Engineering University of Californi1Los AngelesLos AngelesCA90095United States Department of Bioengineering University of Californi1Los AngelesLos AngelesCA90095United States

Designing adhesive hydrogels with optimal properties for the treatment of injured tissues is challenging due to the tradeoff between material stiffness and toughness while maintaining adherence to wet tissue surfaces. In most cases, bioadhesives with improved mechanical strength often lack an appropriate elastic compliance, hindering their application for sealing soft, elastic, and dynamic tissues. Here, we present a novel strategy for engineering tissue adhesives in which molecular building blocks are manipulated to allow for precise control and optimization of the various aforementioned properties without any tradeoffs. To introduce tunable mechanical properties and robust tissue adhesion, the hydrogel network presents different modes of covalent and noncovalent interactions using N-hydroxysuccinimide ester (NHS) conjugated alginate (Alg-NHS), poly (ethylene glycol) diacrylate (PEGDA), tannic acid (TA), and Fe^(3+) ions. Through combining and tuning different molecular interactions and a variety of crosslinking mechanisms, we were able to design an extremely elastic (924%) and tough (4697 kJ/m3) multifunctional hydrogel that could quickly adhere to wet tissue surfaces within 5 s of gentle pressing and deform to support physiological tissue function over time under wet conditions. While Alg-NHS provides covalent bonding with the tissue surfaces, the catechol moieties of TA molecules synergistically adopt a mussel-inspired adhesive mechanism to establish robust adherence to the wet tissue. The strong adhesion of the engineered bioadhesive patch is showcased by its application to rabbit conjunctiva and porcine cornea. Meanwhile, the engineered bioadhesive demonstrated painless detachable characteristics and in vitro biocompatibility. Additionally, due to the molecular interactions between TA and Fe3+, antioxidant and antibacterial properties required to support the wound healing pathways were also highlighted. Overall, by tuning various molecular interactions, we were able to develop a single-hydrogel platform wit

关键词： Molecular engineering Tough hydrogel Bioadhesive Multifunctionality

Composition characterization and transformation mechanism of dissolved organic phosphorus in wastewater treatment using 31P NMR spectroscopy

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Frontiers of Environmental Science & Engineering 2024年第3期18卷 103-113页

作者： yuting Zhang Wei Shang SoonThiam Khu Xingcan zheng Yongli Sun Pengfeng Li Miao Gu Wen-an Zhang Huanmei Ma National Engineering Research Center For Urban Water&Wastewater North China Municipal Engineering Design&Research Institute Co.Ltd.Tianjin 300381China School of Environment Science&Engineering Tianjin UniversityTianjin 300350China

The migration and transformation of phosphorus components in wastewater treatment plants(WWTPs)play a crucial role in the convergence and circulation of phosphorus.However,the composition and variation of dissolved organic phosphorus(DOP)in WWTPs were unclear because of its complex nature,hindering its efficient detection.In this study,the DOP species and their transformation during the treatment process in WWTP were comprehensively analyzed.First,two enrichment methods were assessed for their effectiveness at facilitating wastewater analysis:lyophilization and aluminum salt precipitation.Aluminum salt precipitation was found to be better because its application allowed 31P nuclear magnetic resonance(31P NMR)spectroscopy to identify more species in the secondary effluent:orthophosphate(Ortho-P)(81.1%–89.3%of the dissolved total phosphorus),pyrophosphates(Pyro-P)(0%–2.3%),orthophosphate monoesters(Mono-P)(7.0%–10.77%),orthophosphate diesters(Di-P)(1.0%–2.96%),and phosphonate(Phos-P)(1.7%–5.16%).Furthermore,the variation and transformation mechanism of phosphorus,particularly those of DOP,during the entire sewage-treatment process were elucidated.Among the treatment steps,biological treatment combined tertiary treatment achieved better DOP removal efficiencies.Therein,biological treatment mainly removed Mono-P and Di-P with removal efficiencies of 33.3%and 41.7%compared with the effluent of the grit chamber.Di-P has higher bioavailability and is more easily converted and utilized by microorganisms than Mono-P.However,Phos-P,with low bioavailability,was hardly utilized by microorganisms,which showed only 18.4%removal efficiency in biological treatment.In tertiary treatment,coagulation process exhibited higher removal ability of Ortho-P(69.1%)and partial removal efficiencies of DOP,resulting in an increase in the DOP proportion in TP.In addition,Phos-P could not be effectively removed through the biological treatment and was only partially reduced via the adsorption process by large particles,zoogloea or multinuclear

关键词： Municipal wastewater Dissolved organic phosphorus Composition Transformation 31P nuclear magnetic resonance

Oncogenic β-catenin-driven liver cancer is susceptible to methotrexate-mediated disruption of nucleotide synthesis

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Medical Journal 2024年第2期137卷 181-189页

作者： Fangming Liu yuting Wu Baohui Zhang Shuhui Yang Kezhuo Shang Jie Li Pengju Zhang Weiwei Deng Linlin Chen Liang zheng Xiaochen Gai Hongbing Zhang Department of Physiology State Key Laboratory of Common Mechanism Research for Major DiseasesHaihe Laboratory of Cell EcosystemInstitute of Basic Medical Sciences and School of Basic MedicineChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100005China Department of Physiology Institute of Basic Medical Sciences and School of Basic MedicineGraduate School of Peking Union Medical CollegeChinese Academy of Medical SciencesBeijing100005China Department of Physiology School of Life ScienceChina Medical UniversityShenyangLiaoning 110122China School of Life Sciences Westlake UniversityHangzhouZhejiang 310024China Key Laboratory of Pediatric Hematology and Oncology Ministry of HealthInstitute of Pediatric Translational MedicineShanghai Children’s Medical CenterShanghai Jiao Tong School of MedicineShanghai 200127China

Background:Liver cancer is largely resistant to chemotherapy.This study aimed to identify the effective chemotherapeutics forβ-catenin-activated liver cancer which is caused by gain-of-function mutation of catenin beta 1(CTNNB1),the most frequently altered proto-oncogene in hepatic neoplasms.Methods:Constitutiveβ-catenin-activated mouse embryonic fibroblasts(MEFs)were established by deleting exon 3(β-catenin^(Δ(ex3)/+)),the most common mutation site in CTNNB1 gene.A screening of 12 widely used chemotherapy drugs was conducted for the ones that selectively inhibitedβ-catenin^(Δ(ex3)/+)but not for wild-type MEFs.Untargeted metabolomics was carried out to examine the alterations of metabolites in nucleotide synthesis.The efficacy and selectivity of methotrexate(MTX)onβ-catenin-activated human liver cancer cells were determined in vitro.Immuno-deficient nude mice subcutaneously inoculated withβ-catenin wild-type or mutant liver cancer cells and hepatitis B virus(HBV);β-catenin^(lox(ex3)/+)mice were used,respectively,to evaluate the efficacy of MTX in the treatment ofβ-catenin mutant liver cancer.Results:MTX was identified and validated as a preferential agent against the proliferation and tumor formation ofβ-catenin-activated cells.Boosted nucleotide synthesis was the major metabolic aberration inβ-catenin-active cells,and this alteration was also the target of MTX.Moreover,MTX abrogated hepatocarcinogenesis of HBV;β-catenin^(lox(ex3)/+)mice,which stimulated concurrent Ctnnb1-activated mutation and HBV infection in liver cancer.Conclusion:MTX is a promising chemotherapeutic agent forβ-catenin hyperactive liver cancer.Since repurposing MTX has the advantages of lower risk,shorter timelines,and less investment in drug discovery and development,a clinical trial is warranted to test its efficacy in the treatment ofβ-catenin mutant liver cancer.

关键词： Liver cancer β-catenin Methotrexate Nucleotide synthesis Chemotherapy

Magnesium-L-threonate treats Alzheimer's disease by modulating the microbiota-gut-brain axis

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2024年第10期19卷 2281-2289页

作者： Wang Liao Jiana Wei Chongxu Liu Haoyu Luo yuting Ruan Yingren Mai Qun Yu Zhiyu Cao Jiaxin Xu Dong zheng Zonghai Sheng Xianju Zhou Jun Liu Department of Neurology The Second Affiliated Hospital of Guangzhou Medical UniversityGuangzhouGuangdong ProvinceChina Special Medical Service Center Neuroscience CenterIntegrated Hospital of Traditional Chinese MedicineSouthern Medical UniversityGuangdongGuangdong ProvinceChina Department of Rehabilitation The Second Affiliated HospitalGuangzhou Medical UniversityGuangzhouGuangdong ProvinceChina Department of Neurology Sun Yat-sen Memorial HospitalSun Yat-sen UniversityGuangzhouGuangdong ProvinceChina Department of Neurology The Affiliated Brain Hospital of Guangzhou Medical UniversityGuangzhouGuangdong ProvinceChina Institute of Biomedical and Health Engineering Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhenGuangdong ProvinceChina

Disturbances in the microbiota-gut-brain axis may contribute to the development of Alzheimer's disease. Magnesium-L-threonate has recently been found to have protective effects on learning and memory in aged and Alzheimer's disease model mice. However, the effects of magnesium-L-threonate on the gut microbiota in Alzheimer's disease remain unknown. Previously, we reported that magnesium-L-threonate treatment improved cognition and reduced oxidative stress and inflammation in a double-transgenic line of Alzheimer's disease model mice expressing the amyloid-β precursor protein and mutant human presenilin 1(APP/PS1). Here, we performed 16S r RNA amplicon sequencing and liquid chromatography-mass spectrometry to analyze changes in the microbiome and serum metabolome following magnesium-Lthreonate exposure in a similar mouse model. Magnesium-L-threonate modulated the abundance of three genera in the gut microbiota, decreasing Allobaculum and increasing Bifidobacterium and Turicibacter. We also found that differential metabolites in the magnesiumL-threonate-regulated serum were enriched in various pathways associated with neurodegenerative diseases. The western blotting detection on intestinal tight junction proteins(zona occludens 1, occludin, and claudin-5) showed that magnesium-L-threonate repaired the intestinal barrier dysfunction of APP/PS1 mice. These findings suggest that magnesium-L-threonate may reduce the clinical manifestations of Alzheimer's disease through the microbiota-gut-brain axis in model mice, providing an experimental basis for the clinical treatment of Alzheimer's disease.

关键词： Alzheimer's disease APP/PS1 double-transgenic Alzheimer's disease mouse model inflammation intestinal barrier dysfunction magnesium-L-threonate microbiome microbiota-gut-brain axis oxidative stress serum metabolites

The dynamic characteristics of saturated remolded loess under cyclic load

在线全文

学校读者我要写书评

暂无评论

Earthquake Research Advances 2024年第2期4卷 27-35页

作者： yuting Fu Yanbo Cao Jiaxu Kong Jia zheng Jiaqi Mu Jie Wang Jianqi Zhuang College of Geological Engineering and Geomatics Key Laboratory of Western China Mineral Resources and Geological EngineeringChang’an UniversityXi’an710054China

Due to the joint development characteristic and macropore structure of loess,it is easy to cause structure collapse under earthquake or artificial vibration.The study on the loess disaster effect and its mechanism under earthquake action is insufficient due to its complexity.Hence,to study the deformation and mechanical properties more accurately,the dynamic characteristics of saturated remolded loess under cyclic dynamic load were tested using a GDS dynamic triaxial instrument in this paper.The test results show that strain and pore water pressure increase gradually at different rates with the development of vibration,and there is an obvious inflection point in the time-history curve of both.When the number of vibrations(N)exceeds this point,the strain increases rapidly,and pore water pressure tends to be stable.Under the action of large amplitude and low-frequency dynamic load,the strain and pore water pressure increase rapidly with fewer vibrations and the deviator stress(q)decreases rapidly,while the sample achieves damage faster with the increase of amplitude.During the application of a dynamic load,the effective stress(p)gradually decreases and its rate of change slows down.Finally,when the saturated remolded loess is subjected to a constant-amplitude dynamic load,the combination of large amplitude and low frequency leads to the failure of the sample in the shortest time.

关键词： Loess Pore water pressure Strain Frequency Amplitude Quake(vibration)

Chemical vapor deposited diamond with versatile grades:from gemstone to quantum electronics

在线全文

学校读者我要写书评

暂无评论

Frontiers of Materials Science 2022年第1期16卷 17-54页

作者： yuting zheng Chengming LI Jinlong LIU Junjun WEI Xiaotong ZHANG Haitao YE Xiaoping OUYANG Institute for Advanced Materials and Technology(IAMT) State Key Laboratory for Advanced Metals and MaterialsUniversity of Science and Technology BeijingBeijing 100083China Shunde Graduate School University of Science and Technology BeijingFoshan 528399China School of Computer and Communication Engineering University of Science and Technology BeijingBeijing 100083China Beijing Advanced Innovation Center for Materials Genome Engineering University of Science and Technology BeijingBeijing 100083China School of Engineering University of LeicesterLeicester LE17RHUK School of Materials Science and Engineering Xiangtan UniversityXiangtan 411105China

Chemical vapor deposited(CVD)diamond as a burgeoning multifunctional material with tailored quality and characteristics can be artificially synthesized and controlled for various applications.Correspondingly,the application-related“grade”concept associated with materials choice and design was gradually formulated,of which the availability and the performance are optimally suited.In this review,the explicit diversity of CVD diamond and the clarification of typical grades for applications,i.e.,from resplendent gem-grade to promising quantum-grade,were systematically summarized and discussed,according to the crystal quality and main consideration of ubiquitous nitrogen impurity content as well as major applications.Realizations of those,from quantum-grade with near-ideal crystal to electronic-grade having extremely low imperfections and then to optical,thermal as well as mechanical-grade needing controlled flaws and allowable impurities,would competently fulfill the multi-field application prospects with appropriate choice in terms of cost and quality.Exceptionally,wide range defects and impurities in the gem-grade diamond(only indicating single crystal),which are detrimental for technology applications,endows CVD crystals with fancy colors to challenge their natural counterparts.

关键词： CVD diamond synthesis and characterization quality and impurity grading application

Carbon materials:The burgeoning promise in electronics

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2022年第3期29卷 404-423页

作者： yuting zheng Junjun Wei Jinlong Liu Liangxian Chen Kang An Xiaotong Zhang Haitao Ye Xiaoping Ouyang Chengming Li Institute for Advanced Materials and Technology(IAMT State Key Laboratory for Advanced Metals and MaterialUniversity of Science and Technology BeijingBeijing 100083China Shunde Graduate School University of Science and Technology BeijingFoshan 528399China School of Computer and Communication Engineering University of Science and Technology BeijingBeijing 100083China School of Engineering University of LeicesterLeicester LE17RHUnited Kingdom School of Materials Science and Engineering Xiangtan UniversityXiangtan 411105China

Current electronic technology based on silicon is approaching its physical and scientific limits. Carbon-based devices have numer- ous advantages for next generation electronics (e.g., fast speed, low power consumption and simple process), that when combined with the unique nature of the versatile allotropes of carbon elements, are creating an electronics revolution. Carbon electronics are greatly advancing with new preparations and sophisticated designs. In this perspective, representatives with various dimensions, e.g., carbon nanotubes, graphene, bulk diamond, and their extraordinary performance, are reviewed. The associated state-of-the-art devices and composite hybrid all-carbon structures are also emphasized to reveal their potential in the electronics field. Advances in commercial production have improved the cost effi-ciency, material quality, and device design, accelerating the promise of carbon materials.

关键词： carbon materials nanotube graphene diamond electronic devices

On-surface synthesis and characterization of polyynic carbon chains

在线全文

学校读者我要写书评

暂无评论

National Science Review 2024年第3期11卷 192-199页

作者： Wenze Gao Wei zheng Luye Sun Faming Kang zheng Zhou Wei Xu Interdisciplinary Materials Research Center School of Materials Science and Engineering Tongji University

Carbyne, an elusive sp-hybridized linear carbon allotrope, has fascinated chemists and physicists for decades. Due to its high chemical reactivity and extreme instability, carbyne was much less explored in contrast to the sp2-hybridized carbon allotropes such as graphene. Herein, we report the on-surface synthesis of polyynic carbon chains by demetallization of organometallic polyynes on the Au（111） surface;the longest one observed consists of ～60 alkyne units（120 carbon atoms）. The polyynic structure of carbon chains with alternating triple and single bonds was unambiguously revealed by bond-resolved atomic force microscopy. Moreover, an atomically precise polyyne, C14, was successfully produced via tip-induced dehalogenation and ring-opening of the decachloroanthracene molecule(C14Cl10) on a bilayer NaCl/Au（111） surface at 4.7 K, and a band gap of 5.8 eV was measured by scanning tunnelling spectroscopy,in a good agreement with the theoretical HOMO–LUMO gap（5.48 eV）.

关键词： polyyne scanning probe microscopy carbon allotrope on-surface synthesis organometallic polyyne