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BACKGROUND: The stable and controllable release of nitric oxide from artificial blood vessel materials at the physiological level is not only the key technology to inhibit the formation of thrombus on small-diameter artificial blood vessel inner walls, but also is of great significance for developing novel artificial blood vessel materials. OBJECTIVE: To review the research and application progress of artificial blood vessel materials in recent years, and focus on introducing nitric oxide-releasing artificial blood vessel materials. METHODS: CNKI, Wanfang, Google Scholar, and PubMed databases were searched with key words such as “vascular graft, blood vessel, catalytic nitric oxide, tissue engineering” in English, “artificial blood vessel, catalytic NO” in Chinese from January 2000 to July 2020 for relevant articles. The retrieved articles were screened and summarized. RESULTS AND CONCLUSION: A series of polymer materials, coating materials and nano composite materials exhibited similar nitric oxide production flux and release rate with natural endothelial tissues. Among them, artificial blood vessel materials loaded with organic selenium, copper ions, keratin, and nano-noble metals have shown great potentialities in the treatment of cardiovascular diseases. The artificial blood vessel materials loaded with organic selenium had long catalytic durations, good biocompatibilities, and excellent mechanical properties. The artificial blood vessel materials loaded with copper had good biological safeties and strong anti-thrombotic abilities. The performance of artificial blood vessel materials loaded with organic selenium and copper ions showed longterm and stable catalytic abilities and selective enhancement abilities of endothelial cell activities. Artificial blood vessel materials containing keratin showed excellent cell compatibility and functional expansibilities. The other artificial blood vessel materials containing substances that could catalyze nitric oxide production also exhibited good potential developments in the future. Up to now, the effects of pre-clinical development or post-clinical trials of implantable biomaterials that release nitric oxide are still unclear, and some important technical issues such as the release time of nitric oxide and the effects on endothelial cells need to be resolved. [ABSTRACT FROM AUTHOR]

The sodium lignin sulfonate was grafted into polyacrylamide hydrogel to synthesize polyacrylamide-lignin sulfonate hydrogel. The ammonium molybdate was introduced into the hydrogel network by immersion process to realize vision display. The absorbance, transparency, structure and morphology of sodium lignosulfonate-polyacrylamide hydrogel were measured by UV-Vis, FT-IR and SEM, respectively. The UV-Vis measurement results show that the hydrogel had the advantages of low cost, easy preparation, and excellent performance in quick response within 5 min. In addition, the photochromic and fading processes of hydrogels could be precisely controlled by UV light at different time and temperatures. FT-IR measurements showed that sodium lignosulfonate was successfully incorporated into the polyacrylamide hydrogel. SEM results show that the hydrogel exhibited a dense structure after complete drying, which made the hydrogel less susceptible to fading after photochromism. [ABSTRACT FROM AUTHOR]

In order to further understand the impact of climate change on surface water resources in the upper and middle reaches of the Yellow River, nearly 50 a hydrologic meteorological element data were analyzed to the region above Huayuankou Station. Based on the principle of annual water and energy balance, a regional surface water resources volume simulation model based on Buydko hydrothermal coupling balance was built and the water cycle constitutive relationship was described in a simplified form of annual scale. The results show that 1°C increase in temperature might result in a surface runoff decrease of 6.8% and a 10% precipitation increase might result in a streamflow increase of 21.3%. [ABSTRACT FROM AUTHOR]

In order to solve the issues of poor interaction, shape distortion and information loss in BIM model analysis of hydraulic engineering works, a universal digital twin hydraulic engineering lightweight technology based on BIM was proposed. The lightweight of hydraulic engineering projects was divided into five aspects of BIM modeling, data structure standardization, model extraction and transformation, model compression and transmission, model analysis and rendering. According to the characteristics of hydraulic engineering works data and business application requirements, lightweight measures were proposed in a targeted manner to give full play to the three-dimensional visualization and data performance of BIM technology and realize business collaborative application. This method was applied to the phase I of the Hanjiang to Weihe River Water Diversion Project, and the lightweight of the engineering geological model was realized by specifying the geometric configuration representation of the model, the standardized data storage space, the necessary information extraction and conversion methods of the model, the model compression tools and transmission methods, the model analysis tools and rendering methods. The number of frames per second (FPS) of the lightweight engineering geological model was increased from 10 to 55, which verified the effectiveness of the method. [ABSTRACT FROM AUTHOR]

In view of the fact that there are many majors in water conservancy and hydropower engineering, the difference of modeling tools will lead to the difficulty of data transfer and even data loss when professional collaboration or phased results are transferred. This paper innovatively proposed to extend the original IFC (Industry Foundation Class) data structure on demand, established the extended data structure method of digital twin water conservancy and hydropower engineering, and formed the extended IFC expression method of water conservancy and hydropower engineering for semantic expression, geometric expression and attribute set expression, so as to provide standardized storage space for the easily lost data in water conservancy and hydropower engineering. On this basis, based on Autodesk Revit software, with the help of Revit IFC Exporter open source toolkit, the extended IFC export function including geometric information and attribute information was developed, and the dam structure was extended and exported, which verified the operability of the extended data structure establishment method. Finally, through the data transfer case, it is proved that the method can effectively ensure that the engineering information is not lost during the transfer process. [ABSTRACT FROM AUTHOR]

In this paper, a green carboxymethyl cellulose sodium (CMC)/gelatin (GL)-glut ar aldehyde (GA) composite aerogel (CL-A) was prepared by using the principle of chemical cross-linking and freeze-drying technology. The effects of different proportions of carboxymethyl cellulose sodium (CMC), gelatin (GL) and different contents of glutaraldehyde (GA) on the microstructure, thermal stability, mechanical strength and thermal insulation and thermal insulation properties of the aerogel were investigated. The experimental results obtained after trying different raw material ratios showed that the compression modulus of the composite aerogel (Cj I弋一Ain)with the ratio of sodium carboxymethyl cellulose (CMC) to gelatin (GL) of 1:2 and the addition of glutar-aldehyde (GA) of 15% is the highest of 3.()3 Mpa, which is 7 times higher than that of pure sodium carboxym-ethyl cellulose (CMC) aerogel, and the mechanical properties have been enhanced effectively. The thermal conductivity of composite aerogel (Ci I<_) is the lowest, which is as low as ().022 W/(m • k) with a better heat preservation effect. At the same time, the composite aerogel (Ci I-) has a denser porous three-dimensional network, which improves the morphology of the composite aerogel to a certain degree. Lastly, the composite aerogel (C J弋-八")has up to 37% residual carbon, which improves the thermal stability to some extent. Tn summary, the compression modulus, microstructure, thermal stability, and thermal insulation properties of the composite aerogel (C-! I<-AI5) after the addition of gelatin (GL) and glutaraldehyde (GA) are improved. [ABSTRACT FROM AUTHOR]

The CNC/PAN composite nanofiber film with high porosity and pure water permeability was prepared by simple electrospinning technology, using concentrated sulfuric acid hydrolyzed skim cotton with high mechanical strength and crystallinity as the reinforcing phase, and combining with polyacrylonitrile (PAN) with good thermal stability and chemical stability. The effect of CNC addition on the properties of the film was investigated through various characterizations, and the results showed that compared with pure PAN, the CNC/PAN composite nanofiber film had good thermal stability, better mechanical properties and hydrophilicity. The changes of thickness, porosity and permeation flux of pure water before and after the use of the film were explored, the oil-water separation performance of the film was analyzed, and its application in the field of water treatment was expanded. [ABSTRACT FROM AUTHOR]

By adding sodium lignosulfonate in the process of polyurethane foam foaming, and using aluminum hypophite (AHP) and expanded graphite (EG) as synergism flame retardants, the sodium lignosulfonate based polyurethane foam (PUF) with flame retardant properties were prepared by “one-step method”. Firstly, the flame retardation properties of the prepared synergism flame retardant PUF materials were characterized by using the limiting oxygen index (LOI) tester. Thermogravimetric analysis (TGA) and CONE calorimetry (CONE) were used to investigate the thermal stability and combustion behavior of flame-retardant PUF materials. Field emission scanning electron microscope (SEM) was used to analyze the microscopic photos of carbon residue after combustion. The analysis results show that when the SLS addition ratio is 4 wt% of the total mass of raw materials, the synergism ratio of AHP and EG is 1∶4, and the addition of the two synergism flame retardants is 30 wt%, the LOI value of biomass-based flame retardant PUF material increases to 31.6%. The addition of coefficent flame retardants improves the thermal stability and carbonization performance of PUF material. Thus, the flame retardant of the material is greatly enhanced. [ABSTRACT FROM AUTHOR]

Toxic activity of pine sawdust wood vinegar on Lymantria dispar L. instar larvae by laboratory bioassay of leaf-dipping method and spraying method was studied，respectively. The results of laboratory bioassay of leaf-dipping method showed that 1 - 2 age Lymantria dispar instar larvae was the best control period for pine sawdust wood vinegar. Corrected mortality of pine sawdust wood vinegar on Lymantria dispar 2nd instar larvae was 63. 33 % (more than median lethal concentration) in 72 h. Laboratory bioassay of spraying method results of pine sawdust wood vinegar on Lymantria dispar 2nd instar larvae showed that the median lethal concentration LC50 of pine sawdust wood vinegar on Lymantria dispar 2nd instar larvae was 17. 17 % . Toxic activity of laboratory bioassay of leaf-dipping method of pine sawdust activated carbon method refined wood vinegar on Lymantria dispar 2nd instar larvae was studied，the results showed that corrected mortality of pine sawdust refined wood vinegar of volume fraction 100 % on Lymantria dispar 2nd instar larvae was 56. 67 % (more than median lethal concentration) in the 7th d. Toxic activity of spraying method is fast acting for wood vinegar. [ABSTRACT FROM AUTHOR]

In this paper, CS-CDS, GL-CDS and SA-CDS were prepared by using chitosan (CS), glucose (GL) and sodium alginate (SA) as the matrix of three biomass materials and melamine. CS-CDS has the best fluorescence performance by comparison. By introducing CS-CDS into the hydrogel based on SA, the specific fluorescence quenching effect of Fe3+ was obtained, and it had good adsorbability and recycle performance. The results show that (CS-CDS)-SA-gel hydrogel can be used as an effective visual detection and adsorption of Fe3+, and has a good application prospect. [ABSTRACT FROM AUTHOR]

Basic parameters of four kinds of wood vinegar( birch, miscellaneous, sawdust and distillated sawdust wood vinegar) were determined by experiment. Minimum inhibitory concentrations( MIC) of wood vinegar on Escherichia coli, Staphylococcus aureus, Bacillus subtilis were respectively determined, and antibacterial mechanism of wood vinegar was studied based on MIC. The results showed that the four kinds of wood vinegar had a strong inhibitory effect on three kinds of bacteria, and distillated sawdust wood vinegar had the strongest inhibitory effect on three kinds of bacteria [diameters of inhibition zone of E. coli, S. aureus, B. subtilis were(24. 13 ± 3. 21), (17. 44 ± 2. 20), (17. 59 ± 2. 79) mm, respectively]. Growth curves of three kinds of tested bacteria were respectively changed based on MIC, cell membrane permeability was increased leading to intracellular electrolytes, protein and carbohydrate exudation, and wood vinegar also inhibited bacterial protein synthesis, made the cell metabolism and ultimately led to cell death, which played the bacteriostatic action. [ABSTRACT FROM AUTHOR]

Photochromic systems are widely used in visual information storage, ultraviolet and infrared light detection and other fields, but they need to be improved in terms of portability and response sensitivity. In this study, CS-Fe3+ composite hydrogel is synthesized using chitosan (CS), acrylamide (PAAm) as matrix, Fe3+ as cross-linking agent, and ammonium molybdate (Mo7) as photochromic medium. The experimental results show that ammonium molybdate and Fe3+ are introduced into the hydrogel network through coordination bonds. Fe3+ can enhance the photochromic performance of the composite hydrogel in a certain concentration range. The composite hydrogel is sensitive to ultraviolet light, and begins to change color after exposure to ultraviolet light for only 5 minutes. By controlling the ultraviolet light irradiation time and the environmental temperature of the hydrogel, the degree of photochromism and the fading rate of the hydrogel can be controlled. After 75 min at 60 °C-CS-Fe3+ 芸 hydrogel can be completely faded and reused. When illu min ate d, the surface of the hydrogel is covered with masks with different patterns, which can record different information on the hydrogel and endow the hydrogel with optical storage performance. The introduction of photochromic materials into hydrogels not only makes the photochromic materials portable, but also has excellent optical sensitivity and can be better used in ultraviolet light detection and visual information storage. [ABSTRACT FROM AUTHOR]

The resistance genes related to infection response of tomato and nematode were screened to provide the basis for mining the key resistance related genes and tomato dis ease resistance breeding. [ Method] lllumina HiSeq ™ 4000 technique was used to seqnence the tomato resistant material F5 genes expression level infected and not infected by Meloidogyne incognita. On the basis of GO and KEGG analysis of the differentially expressed genes, genes resistant to M. incognita were mined. [ Result] 1116 differentially expressed genes were obtained, among which 731 genes were up-regulated, and 385 genes were down-regulated. The functions of these differentially expressed genes were classified into 1830 GO items in three categories: biological process, cell components and molecular functions, and were enriched in 94 KEGG metabolic pathways. GO database and KEGG metabolic analysis on differentially expressed genes revealed 22 genes related to plant-pathogen interaction were differentially expressed, among which 18 genes were up-regnlated. The significantly up-regnlated resistant genes included 12 Ca+ -CAM!CML signal related genes( 11 calmodulin-like protein CML, 1 calmodulin),3 WRKY transcription factor, a protein CNGC. [Conclusion] Ca+ -CAM/CML signal, WRKY transcription factor and cyclic glycolate gated ion channel are important mechanisms of F5 resistance to M. incognita. It can provide reference for exploring interaction between meloidogyne and tomato and mining tomato key resistance related genes. [ABSTRACT FROM AUTHOR]

News opinion summarization aims to produce opinions abstract via refining the text with emotional information, which helps people to know the theme content and tendency of opinions quickly. However, the existing methods only consider the theme and the characteristics of the sentence, which can not get a summary of the text with emotional comments. To address the above problem, this paper presented a method of integrating sentence emotion and topic similarity for Chinese news text opinion summarization. Firstly, it annotated the opinion information of sentences. Secondly, it added opinion information to the LexRank algorithm to compute sentence similarity. Finally, according to the special characteristics of the news title, it calculated the similarity between the sentence and the title. The results of the above three steps were taken into account to generate opinion summary. The results of experiment show that this method is more effective than the classic LexRank algorithm on ROUGE-1 ,ROUGE-2 and ROUGE-W. In addition, it also represents that considering both the emotion and theme can help generating opinion summary effectively. [ABSTRACT FROM AUTHOR]