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Neuroprotection of hyperbaric oxygen therapy in sub-acute traumatic brain injury:not by immediately improving cerebral oxygen saturation and oxygen partial pressure

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Neural Regeneration Research 2016年第9期11卷 1445-1449页

作者： Bao-chun Zhou li-jun liu Bing liu Department of Emergency and Intensive Care Unit the Second Affiliated Hospital of Soochow University Department of Neurosurgery High-tech District Branch of the Second Affiliated Hospital of Soochow University

Although hyperbaric oxygen （HBO） therapy can promote the recovery of neural function in patients who have suffered traumatic brain injury （TBI）, the underlying mechanism is unclear. We hypothesized that hyperbaric oxygen treatment plays a neuroprotective role in TBI by increasing regional transcranial oxygen saturation （rSO2） and oxygen partial pressure （PaO2）. To test this idea, we compared two groups： a control group with 20 healthy people and a treatment group with 40 TBI patients. The 40 patients were given 100% oxygen of HBO for 90 minutes. Changes in rSO2 were measured. The controls were also examined for rSO2 and PaO2, but received no treatment, rSO2 levels in the patients did not differ significantly after treatment, but levels before and after treatment were significantly lower than those in the control group. PaO2 levels were significantly decreased after the 30-minute HBO treatment. Our findings suggest that there is a disorder of oxygen metabolism in patients with sub-acute TBI. HBO does not immediately affect cerebral oxygen metabolism, and the underlying mechanism still needs to be studied in depth.

关键词： nerve regeneration hyperbaric oxygen near-infrared spectroscopy cerebral oxygen saturation traumatic brain injury oxygen partialpressure oxygen metabolism wound healing neurological function blood gas analysis neural regeneration

Diversity of bacteria in different life stages and their impact on the development and reproduction of Zeugodacus tau(Diptera:Tephritidae)

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Insect Science 2021年第2期28卷 363-376页

作者： MdShibly Noman Ge Shi li-jun liu Zhi-Hong li Department of Entomology MOA Key Lab of Pest Monitoring and Green ManagementCollege of Plant ProtectionChina Agricultural UniversityBeijingChina

Fruit flies usually harbor diverse communities of bacteria in their digestive systems,which are known to play a significant role in their ***,little information is available on Zeugodacus tau,a polyphagous pest *** study reports the first extensive analysis of bacterial communities in different life stages and their effect on the development and reproduction of laboratory-reared Z *** bacteria were identified using the conventional method and all bacteria were identified by highthroughput technologies(16S ribosomal RNA gene sequencing of V3-V4 region).A total of six bacterial phyla were identified in larvae,pupae,and male and female adult flies,which were distributed into 14 classes,32 orders,58 families and 96 *** was the most represented phylum in all the stages except ***,Klebsiella,Providencia,and Pseudomonas were identified by conventional and next-generation sequencing analysis in both male and female adult flies,and Enterobacter was found to be the main *** being fed with antibiotics from the first instar larvae,bacterial diversity changed markedly in the adult *** flies laid eggs and needed 20 days before oviposition while the treated flies showed ovary development inhibited and were not able to lay eggs,probably due to the alteration of the *** findings provide the cornerstone for unexplored research on bacterial function in Z tau,which will help to develop an environmentally friendly management technique for this kind of harmful insect.

关键词： antibiotics bacterial diversity fitness oviposition symbiotic bacteria Zeugodacus tau

Stress-Structure Relationship of the Reversible Associating Polymer Network under Start-up Shear Flow

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Chinese Journal of Polymer Science 2021年第3期39卷 387-396,I0008页

作者： Ai-Qing liu li-jun liu Wen-Sheng Xu Xiao-Lei Xu Ji-Zhong Chen li-Jia An College of Chemistry Jilin UniversityChangchun 130012China State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China University of Science and Technology of China Hefei230026China

We adopt Langevin dynamics to explore the stress-structure relationship of telechelic reversible associating polymer gel during startup shear flow, with shear strengths varying from Wi=12.6 to Wi=12640. At weak shear flow Wi=12.6, the shear stress proportionally increases with shear strain at short times, followed by a strain hardening behavior and then passes through a maximum(σmax, γmax) and finally decreases until it reaches the steady state. During the evolution of stress, the gel network is only slightly broken and essentially maintains its framework, and the strain hardening behavior originates from the excessive stretching of chains. On the other hand, the stress-strain curve at intermediate shear flow Wi=505.6 shows two differences from that at Wi=12.6, namely, the absence of strain hardening and a dramatic increase of stress at large strains,which is caused by the rupture of gel network at small strains and the network recovery at large strains, respectively. Finally, at very strong shear flow Wi=6319.7, the gel network is immediately broken by shear flow and the stress-strain curve exhibits similar behaviors to those of classical polymeric liquids.

关键词： Associating polymer Start-up shear Stress-structure relationship

Standard friction prediction model of long-distance hot oil pipelines

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Petroleum Science 2020年第2期17卷 487-498页

作者： Tao Yu Chuan-xian li Bo Yao Zhi-jun Zhang Yi Guo li-jun liu College of Pipeline and Civil Engineering Shandong Provincial Key Laboratory of Oil&Gas Storage and Transportation SafetyChina University of Petroleum(East China)Qingdao 266580ShandongChina Petrochina Oil and Gas Pipeline Control Center Beijing 100007China Richfit Information Technology Co.Ltd Beijing 100007China

We developed a predictive model for the pipeline friction in the 520-730 m^3/h transmission range using the multi-layerperceptron-back-propagation(MLP-BP)method and analyzing the unit friction data after the pigging of a hot oil *** view of the shortcomings of the MLP-BP model,two optimization methods,the genetic algorithm(GA)and mind evolutionary algorithm(MEA),were used to optimize the MLP-BP *** research results were applied to the standard friction prediction of three sections of a hot oil *** the GA and MEA optimizations,the average errors of the three sections were 0.0041 MPa for the GA and 0.0012 MPa for the MEA,and the mean-square errors were 0.083 and 0.067,*** MEA-BP model prediction results were characterized by high precision and small *** MEABP prediction model was applied to the analysis of the wax formation 60 and 90 days after *** analysis results showed that the model can effectively guide pipe pigging and *** was little sample data for the individual transmission and oil temperature steps because the model was based on actual production data modeling and analysis,which may have affected the accuracy and adaptability of the model.

关键词： Hot oil pipeline Friction MLP-BP GA MEA

Enhanced Photocatalytic Activity of ThienyI-Porphyrins-TiO2 for Degradation of 4-Nitrophenol

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Chinese Journal of Chemistry 2013年第2期31卷 230-236页

作者： Wangyang Ma jun li Jingzhou liu Meng Feng Laboratory of Synthetic and Natural Functional Molecule Chemistry of Ministry qf Education College of Chemistry and Material Science Northwest University Xi'an Shannxi 710069 China

5-Mono-（2-thienyl）-10,15,20-triphenyl porphyrin （H2MTP） and its Co（II）, Cu（II）, Zn（ll） metalloporphyrins （CoMTP, CuMTP, ZnMTP） were synthesized and characterized spectroscopically. The corresponding Co（ll）, Cu（ll）, Zn（II） metalloporphyrins-TiO2 photocatalysts were then prepared and characterized by means of scanning electron microscopy （SEM）, energy dispersive spectrometer （EDS）, UV-vis spectra and FT-IR. The photocatalytic activities of these photocatalysts were investigated by testing the photodegradation of 4-nitrophenol （4-NP） in aqueous solution under irradiation with high-pressure mercury lamp and metal halide lamp respectively. The results indicated that these metalloporphyrins greatly enhanced the photocatalytic efficiency of bare TiO2 in degradating the 4-NP, and CuMTP-TiO2 exhibited the highest photocatalytic activity of all photocatalysts. In addition, the first order rate constants of these photocatalytic reactions were calculated.

关键词： thienyl-appended porphyrin metalloporphyrin titanium dioxide photocatalytic degradation 4-nitrophenol

In vitro Degradation of Pure Mg for Esophageal Stent in Artificial Saliva

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Journal of Materials Science & Technology 2016年第5期32卷 437-444页

作者： Rong-Chang Zeng Xiao-Ting li li-jun liu Shuo-Qi li Fen Zhang College of Materials Science and Engineering Shandong University of Science and Technology State Key Laboratory of Mining Disaster Prevention and Control Co-founded by Shandong Province and the Ministry of Science and Technology Shandong University of Science and Technology

Magnesium and its alloys as biodegradable implant materials can be potentially used in cardiovascular and orthopedic devices. However, few studies have focused on its application in esophageal stents. In this paper, time-lapse degradation characteristics of pure Mg were analyzed by scanning electron microscopy, energy dispersive spectroscopy, X-ray diffraction, Fourier transform infrared spectroscopy, hydrogen evolution, pH and electrochemical measurements after immersion in artificial saliva for different times. Results revealed that a dense degradation product film formed on samples, which mainly consisted of two kinds of layers： one was calcium phosphate compounds with different structures; the other was thin magnesium hydrate layer close to the substrate. Less pH increase and low degradation rate were ob- served in the first 5 days of immersion, which can be ascribed to the formation of a thicker and denser layer on the sample surface with increasing immersion time. And then there was an increase in degradation rate and pH values; the deposition layer remained almost intact after immersion for 6 and 8 days. After 10 days of immersion, the degradation rate and pH value remained stable, and the calcium phosphate layer was delaminated and the inner magnesium hydrate layer was exposed. This study indicated that pure Mg exhibited desirable degradation resistance in artificial saliva, which provided magnesiumbased materials with the potential to be used as esophageal stents.

关键词： Magnesium Biomaterials Esophageal stents Degradation Artificial saliva

Role of Hydrodynamic Interactions in the Deformation of Star Polymers in Poiseuille Flow

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Chinese Journal of Polymer Science 2020年第4期38卷 363-370,I0006页

作者： Zhen-Yue Yang Xiao-Fei Tian li-jun liu Ji-Zhong Chen State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China University of Chinese Academy of Sciences Beijing 100049China

Stretching polymer in fluid flow is a vital process for studying and utilizing the physical properties of these molecules,such as DNA linearization in nanofluidic *** studied the role of hydrodynamic interactions(His)in stretching a free star polymer in Poiseuille flow through a tube using mesoscale hydrodynamic *** increasing the flow strength,star polymers migrate toward the centerline of tube due to His,whereas toward the tube wall in the absence of *** analyzing the end monomer distribution and the perturbed flow around the star polymer,we found that the polymer acts like a shield against the flow,leading to additional hydrodynamic drag forces that compress the arm chains in the front of the star center toward the tube axis and lift the arm chai ns at the back toward the tube *** balanced hydrodynamic forces freeze the polymer into a trumpet structure,where the arm chains maintain a steady strongly stretched state at high flow *** contrast,the polymer displays remarkably large conformational change when switching off *** simulation results explained the coupling between His and the structure of star polymers in Poiseuille flow.

关键词： Hydrodynamic interactions Star polymer Poiseuille flow Migration

Tumbling dynamics of individual absorbed polymer chains in shear flow

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Chinese Chemical Letters 2014年第5期25卷 670-672页

作者： li-jun liu Wen-Duo Chen Ji-Zhong Chen li-Jia An State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of Sciences

The tumbling dynamics of individual absorbed polymer chains in shear flow is studied by employing multi-particle collision dynamics simulation techniques combined with molecular dynamics *** find that the dependence o... 详细信息

关键词： Shear Simulation Tumbling Absorbed

Microstructure and stress-rupture property of an experimental single crystal Ni-base superalloy with different heat treatments

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Rare Metals 2014年第2期33卷 144-148页

作者： Jing-Yang Chen La-Mei Cao Ming Xue li-jun liu Science and Technology on Advanced High Temperature Structural Materials Laboratory Beijing Institute of Aeronautical Materials

The influence of heat treatment on the microstructure and stress-rupture property at 1,100 °C/140 MPa was investigated in a 5.0 wt% Re containing experimental single crystal Ni-base superalloy. The results indicate that the γmorphology is nearly cuboidal in the dendrite core after conventional heat treatment. The lattice misfit of alloy becomes more negative after modified heat treatment and results in more cuboidal γ precipitates than that after conventional heat treatment. The increased stress-rupture life after modified heat treatment is attributed to higher γ volume fraction, more negative lattice misfit, well-rafted structure, and narrower c channel width.

关键词： Superalloy Heat treatment γprecipitate Lattice misfit Stress-rupture property