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The changes in dip angles of different working faces in the area affected by folding structures cause the variability of mining pressure features. In order to solve the above problem, with the seventh mining area of Baojishan Coal Mine as the engineering background, a combination of on-site research, theoretical analysis, numerical simulation, and on-site industrial experiments is used. The dynamic and static loads during mining of different working faces in coal seams with varying dip angles are studied. The results indicate the following points. ① The accumulated acoustic emission(AE) energy of the coal rock composite system with a stiffness value greater than 0 is smaller than that of the coal rock composite system with a stiffness value less than 0. This indicates that when the stiffness value of the coal rock composite system is less than 0, AE energy is more likely to accumulate. When the stiffness value of the coal rock composite system is less than 0, the larger its absolute value, the higher the AE energy can be accumulated. ② As the dip angle of the coal seam increases, the concentrated static load inside the solid coal side of the goaf roadway decreases, and the concentrated static load inside the coal pillar side increases. The hanging top section required for the cracking of the high and thick hard key layer is longer. ③ When the dip angle of the coal seam is small, the combined system of coal and rock in the two sides of the goaf roadway is prone to inducing dynamic failure type II rock burst under the combined action of dynamic and static loads. When the dip angle of the coal seam is large, the coal rock combination system inside the coal pillar side of the goaf roadway is prone to inducing static or dynamic failure type I rock burst under high concentrated static load. ④ During the mining period of the 705 fully mechanized top coal caving face, the coal pillar side of the goaf roadway is prone to inducing static or dynamic failure type I rock burst. After implementing anti erosion measures, the electromagnetic radiation value decreases by up to 67.3%. The coal rock combination system is not easy to induce rock burst.

To investigate the dose-effect relationship of Tremella fuciformis polysaccharides against water migration and adhesion in fresh wet noodles, we evaluated the farinograph and texture properties of fresh wet noodles made with different amounts of T. fuciformis polysaccharides, and we also characterized them by Fourier transform infrared (FTIR) spectroscopy, low field nuclear magnetic resonance (LF-NMR) spectroscopy, dynamic rheological analysis and laser confocal microscopy. The results showed that the fresh wet noodles with T. fuciformis polysaccharides had lower apparent viscosity compared with the control group without the polysaccharides, and the polysaccharides could inhibit the migration of free water, resulting in changes in water distribution. Compared with the control group, the relative α-helix content of fresh wet noodles with T. fuciformis polysaccharides increased by 9.96% and the relative β-turn content decreased by 7.11%. Addition of T. fuciformis polysaccharides in noodles enhanced the structural orderliness of gluten proteins and the microstructural compactness, reduced the exposure of starch granules, and improved the water-holding capacity, which in turn made noodles more stable during storage. The thermal properties and dynamic rheological properties showed that T. fuciformis polysaccharides could promote the formation of a uniform, orderly and stable gluten network structure in fresh wet noodles. Among all concentrations tested, addition of 0.5% T. fuciformis polysaccharides was the most effective in inhibiting water migration and improving adhesion during storage of fresh wet noodles.

The monitoring of the overflow concentration of the thickener is the key to realize intelligent dosing of coal slurry. The overflow concentration monitoring method based on the sensor will lead to the delay of flocculant regulation. In order to solve the above problem, a prediction method of overflow concentration of thickener based on improved sparrow search algorithm (ISSA) and long-short term memory (LSTM) is proposed. Firstly, the correlation analysis and pretreatment of multi-parameter time series in the process of concentration production are carried out to obtain the input variables. Secondly, the multi-strategies are combined to improve sparrow search algorithm (SSA). Tent chaotic map is introduced to initialize the sparrow population to ensure population diversity and speed up algorithm convergence. The optimization process of SSA is improved by using the spiral predation strategy to balance both local development and global search capabilities. The firefly perturbation strategy is used to perturb the sparrow search results to improve the global search performance and avoid the algorithm falling into local optimization. Thirdly, ISSA is used to optimize the hyperparameters of the two-layer LSTM network model. Finally, the overflow concentration prediction model based on ISSA-LSTM is established for on-line monitoring. The experimental results show the following points. ① The Ackley function and Rastigin function are selected as test functions. It is concluded that ISSA's global optimization capability and convergence speed are better than those of the particle swarm optimization (PSO) algorithm, whale optimization algorithm (WOA) and standard SSA. ② Among the three improved strategies, the spiral predation strategy plays a leading role in improving the performance of ISSA. The chaotic map and the firefly perturbation strategy coordinate the convergence speed and global search capability of the algorithm to further improve the optimization performance of the algorithm. ③ ISSA is used to optimize the hyperparameters of LSTM, which solves the problem of under-fitting or over-fitting when the values are determined by subjective experience. The prediction precision of overflow concentration of the ISSA-LSTM model reaches 97.26%, which is higher than that of double-layer LSTM, SSA-LSTM, and least square support vector machine (LSSVM) models. ④ Data pretreatment can improve the precision of the model, and the prediction precision of overflow concentration after noise reduction is improved by 30.25% compared with that before noise reduction.

To improve the mechanical properties of carbon fiber reinforced polymer (CFRP) bonding interface, the surface treatment of CFRP was performed using low-temperature oxygen plasma treatment equipment. The surface physico-chemical properties including surface wettability, surface energy, surface morphology and surface chemical components of CFRP were characterized by contact angle measurement, scanning electron microscopy (SEM), atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS) test equipment, as well as the mechanical properties of CFRP bonding interface was tested by double cantilever beam (DCB) test. The results show that the water contact angle of surface decreases from 97° to 29° with the increase of oxygen plasma treatment time from 0 s to 30 s, as well as the surface wettability of CFRP is the best and the percentage of polar components increases significantly. As the increase of treatment time, the surface roughness and the maximum height difference of CFRP decrease significantly, and more nanoscale grooves with valley distribution are formed and thus the surface area of substrate increases. Meanwhile, the content of oxygen-containing polar functional groups including C—O and C＝O on the surface are increased obviously, the content of C—C/C—H and Si—C functional groups are decreased, and the surface contaminants are effectively removed or transformed. In comparison with the untreated specimens, the maximum peeling load and mode Ⅰ fracture toughness of CFRP adhesive interface are improved by 1.01 times (62.73 N) and 1.92 times (649.21 J/m2) after oxygen plasma treatment for 20 s, respectively. The study reveals that oxygen plasma treatment can significantly improve the physico-chemical properties of CFRP surface, which is conducive to better bonding between CFRP and adhesive, and improve the peel strength and toughness of the adhesive interface.

Aiming at the problem of low detection accuracy caused by insufficient target feature extraction in substation 3D scene, a voxelization-based 3D object detection model AugSecond for substation scene is proposed, which is designed based on the Second network structure. It introduces a triple attention mechanism in the voxel feature encoding stage, which focuses on multi-dimensional attention to enhance the key information of the target and reduce the interference of irrelevant feature information. It designes asymmetric sparse convolutional networks, uses asymmetric convolution to improve convolutional kernel representation capabilities and fuses multi-scale features to enrich target geometry information. Meanwhile, the position regression loss is optimized, and CIoU Loss is used to further consider the geometric correlation between bounding boxes to speed up the network convergence. Experiments on self-built power scene data sets and public data sets show that compared with the benchmark model, AugSecond model significantly improves recognition accuracy and has real-time reasoning speed, which proves the effectiveness of the proposed model. [ABSTRACT FROM AUTHOR]

In order to obtain the better torsional vibration characteristics of the traction unit of the shearer,taking a new type of shearer traction drive system as the research object,based on its simplified kinetics model,by using the ADAMS software,the dynamics model is built,applies the step load and simulates the dynamic characteristics,and the potential energy curve of each elastic torsion spring is got. The torsional stiffness of the three torsion springs with the greatest potential are optimized and the optimized data are validated by using the above model,the result show that the potential energy distribution of the torsion spring is more uniform and the maximum potential energy value of each torsion spring has obviously decreased compared with the previous optimization. This method is of great significance to improve the torsional vibration characteristics of the traction unit of the shearer.

A pair of undamaged gears and a pair of gears with crack on the root of tooth are simulated and analyzed by using the LS- DYNA,and the change of the acceleration signals and meshing force of any node on the gear can be got. Through the simulation calculation,the meshing force and node acceleration curve can be observed to understand the influence of the meshing impact force on gear body. The study shows that,the influence of the tooth root crack on gear transmission can accurately be simulated by using the LS- DYNA,and all these curves have strict periodicity. A new kind of thought and method for gear fault diagnosis will be provided.

With the V-shaped support continuous rigid frame bridge as the engineering background, the 0# block with V-shaped support was used for the construction stage analysis and construction working condition analysis. According to the analysis results, the following conclusions can be drawn: The stress of the 0# block with V-shaped support met the specification requirements during the construction process, and the stress characteristics during the construction process can be used for reference by designers and constructors. The 0# block with V-shaped support was more sensitive to horizontal displacement along the bridge and vertical displacement, and structural displacement monitoring should be paid attention to during the construction process. There is a certain gap between the analysis results of the construction working condition analysis and the more real analysis results of the construction stage, and the construction stage analysis is used as much as possible in the calculation and analysis of the actual project. [ABSTRACT FROM AUTHOR]

The effects of different mass concentrations of Pholiota nameko polysaccharides on pasting, rheological, texture, thermodynamic properties and microstructure of corn starch were studied. To explore the interaction mechanism between polysaccharides and corn starch and reveal the dose-effect relationship between polysaccharides and starch quality. The results showed that Pholiota nameko polysaccharide could improve the viscosity and gelatinization temperature of the compound system, indicating that the polysaccharide delayed the gelatinization process. When the mass concentration of Pholiota nameko polysaccharides was 0.9 g/mL, the breakdown value of the compound system was 1.77mPa·s, the setback value was 3.63mPa·s and the gelatinization enthalpy was 3.95 J/g, indicating that the anti-aging effect and stability of the compound system were the best. With the increase of polysaccharide mass concentration, the viscoelasticity and pseudoplasticity of the complex system gradually increased, and the flow index gradually decreased. Fourier transform infrared spectroscopy analysis showed that the interaction between the polysaccharides and corn starch was through hydrogen bond, and the hydrogen bond interaction was the strongest when the polysaccharide mass concentration was 0.9 g/mL. The results of cryo-electron microscopy showed that the microstructure of the compound system was honeycomb with uniform pores when the polysaccharide mass concentration was 0.6 g/mL. [ABSTRACT FROM AUTHOR]

In order to develop hemp knitted blended yarn products, the process of hemp/cotton knitted grey yarn using siro spinning was discussed. The selection of materials, the technological parameters and technique for the forespinning were investigated. Moreover, the technological parameters of siro spinning, such as twist coefficient, spindle speed and draft ratio in the rear area, were optimized by one-way ANOVA. Finaly, the process conditions of hemp/cotton 70/30 22 tex siro spun knitted grey yarn were determined. The results show that when the siro spinning process parameters are twist coefficient 380, spindle speed 9 000 r/min, and draft ratio in the rear area of 1. 15, the indicators of yarn performance are better. [ABSTRACT FROM AUTHOR]

In order to confirm the acid-erosion of archaea in deep reservoir, via the high throughput sequencing technology, we analyzed the archaea community composition and diversity in Bohai S-oilfield, revealed three sulfate-reducing archaea Thermococcales, Archaeoglobales and Desulfurococcales. By constructing the phylogenetic trees of sulfate-reducing functional genes aprA, dsrA, and dsrB, we obtained the respective abundance of these functional genes in Archaeoglobales. The percentages of Archaeoglobales were dominant in dsrA and dsrB, leading to a key role in reducing sulfites into hydrogen sulfide. Moreover, we compared the archaea community composition between treatment well and non-treatment well against hydrogen sulfide in the same block. Due to the bio-competitive exclusion (BCX), Thermococcus was down-regulated in abundance by 23. 84%, showing a definite suppression towards some sulfate-reducing archaea. Our findings uncovers the genus and relevant functional genes of sulfate-reducing archaea, to facilitate the development of management system against the secondary hydrogen sulfide in oil reservoir. [ABSTRACT FROM AUTHOR]

This paper analyzes the problems existing in the development of public art education in China, and puts forward the ideas of the curriculum system construction and knowledge framework of public art teaching system. It is pointed out that public art is not only a new contemporary art major, training scarce professionals for the soft power construction to build our country one of the cultural powers, but also changes the track of art development, from a niche to the public, from sensation to interference, to problem-solving. Such transformation expands the aesthetic attributes of art, changing and promoting the development of society in an aesthetic way. It is necessary to fully realize that the public art plays both a social and historical role in the construction of public art major. [ABSTRACT FROM AUTHOR]

BACKGROUND: Lumbosacral transitional vertebra is a commonly seen congenital spinal deformity, and the changes in the muscle innervation pattern and the sensory dermatomes of the lumbosacral nerve roots have been reported, but the changes and its guidance significance for the surgeries of lumbar disc herniation have not been clarified systematically. OBJECTIVE: To explore the possibility of changes in the muscle innervation pattern and the sensory dermatomes of the lumbosacral nerve roots when there is a lumbosacral transitional vertebra. METHODS: The study was in accordance with the ethical requirements of Affiliated HospitaI of Binzhou Medical University, and the subjects and their families signed the informed consents. The medical records of 321 patients with single segment lumbar disc herniation who underwent surgical treatment were analyzed retrospectively. Lumbosacral transitional vertebrae were present in 38 of 321 patients (11.8%). There were 26 cases of sacral lumbarization and 12 cases of lumbar sacralization. Among these 26 patients with sacral lumbarization, 23 had hemiated discs at L5/S1(La) compressing the S1 (L6) nerve root. Of the 12 patients with lumbar sacralization, 8 had herniated discs at L3/4 compressing the L4 nerve root. In the 283 normally configured patients, 138 had herniated discs at L5/S1 compressing the S1 nerve root, 95 had herniated discs at L4/L5 compressing the L5 nerve root, and 47 had herniated discs at L3/L4 compressing the L4 nerve root. The preoperative symptoms of S1 nerve root compression in the patients with sacral lumbarization and of 4 nerve root compression in the patients with lumbar sacralization were compared with those of L4, L5 or S1 nerve root compression in the patients with normal configuration. RESULTS AND CONCLUSION: (1) The distribution of motor function depression caused by S1 nerve root compression was significantly different between sacral lumbarization patients group and normal group (P < 0.05). (2) The distribution of motor function depression caused by L4 nerve root compression was also significantly different between lumbar sacralization patients group and normal group (P < 0.05). (3) The motor function depression caused by S1 nerve root compression in sacral lumbarization patients was similar to that of the L5 nerve root compression in the normal configuration, while the motor function depression caused by L4 nerve root compression in lumbar sacralization patients was similar to that of the L5 nerve root compression in the normal configuration. The analysis of the sensory dermatomes also showed similar results. (4) Our results suggest that the function of lumbosacral nerve roots changes in patients with transitional vertebrae. The S1 nerve roots in patients with sacral lumbarization tend to serve the usual function of L6 nerve roots (nerve roots move up), and the L4 nerve roots in patients with lumbar sacralization tend to serve the usual function of L5 nerve roots (nerve roots move down). [ABSTRACT FROM AUTHOR]

BACKGROUND: Although the mechanism of femoral head necrosis has a series of explanations such as glucocorticoids, ethanol, decompression sickness, sickle cell anemia, and genetic susceptibility, the specific pathogenesis is still unclear. OBJECTIVE: To highlight the genetics of non-traumatic femoral head necrosis by combining recent genetic studies, thus providing new treatments for the repair and reconstruction of femoral head. METHODS: A computer-based online retrieval of CNKI, Wan Fang, PubMed and Web of Science databases was performed to search the related articles published from January 2000 to April 2019. The keywords ware "non-traumatic femoral head necrosis, susceptibility genes, pathogenesis' in Chinese and English, respectively. According to the inclusion and exclusion criteria, the irrelevant and repetitive articles were excluded, and finally 49 eligible articles were included for analysis. RESULTS AND CONCLUSION: Non-traumatic femoral head necrosis is an extremely complex disease whose pathogenesis is caused by a combination of factors rather than a single genetic gene. COL2A1 genetic mutation is the high susceptibility gene to non-traumatic femoral head necrosis. High-coagulation and low-fibrinolytic state-related loci in the blood, interleukin-related gene loci in immune system and lipid-related loci become more and more important in inducing non-traumatic femoral head necrosis. With the deep understanding of human genetic technology, the accuracy of detecting susceptible genes will be continuously improved, which is conducive to the prevention, diagnosis and precise individualized treatment of non-traumatic femoral head necrosis. [ABSTRACT FROM AUTHOR]

MADS -box gene family is a significant transcription factor family that plays a crucial role in regulating plant growth, development, signal transduction, and other processes. In order to study the characteristics of MADS -box gene family in Docynia delavayi (Franch.) Schneid. and its expression during different stages of seed germination, this study used seedlings at different stages of germination as materials and screened MADS -box transcription factors from the transcriptome database of D . delavayi using bioinformatics methods based on transcriptome sequencing. The physical and chemical properties, protein conservative motifs, phylogenetic evolution, and expression patterns of the MADS -box transcription factors were analyzed. Quantitative real-time PCR (qRT-PCR) was used to verify the expression of MADS -box gene family members during different stages of seed germination in D . delavayi . The results showed that 81 genes of MADS -box gene family were identified from the transcriptome data of D . delavayi , with the molecular weight distribution ranged of 6 211.34-173 512.77 Da and the theoretical isoelectric point ranged from 5.21 to 10.97. Phylogenetic analysis showed that the 81 genes could be divided into 15 subgroups, among which DdMADS27 , DdMADS42 , DdMADS45 , DdMADS46 , DdMADS53 , DdMADS61 , DdMADS76 , DdMADS77 and DdMADS79 might be involved in the regulation of ovule development in D . delavayi . The combination of the transcriptome data and the qRT-PCR analysis results of D . delavayi seeds indicated that DdMADS25 and DdMADS42 might be involved in the regulation of seed development, and that DdMADS37 and DdMADS38 might have negative regulation effects on seed dormancy. Previous studies have reported that the MIKC * subgroup is mainly involved in regulating flower organ development. For the first time, we found that the transcription factors of the MIKC * subgroup exhibited a high expression level at the early stage of seed germination, so we speculated that the MIKC * subgroup played a regulatory role in the process of seed germination. To verify the accuracy of this speculation, we selected DdMADS60 and DdMADS75 from the MIKC * subgroup for qRT-PCR experiments, and the experimental results were consistent with the expression trend of transcriptome sequencing. This study provides a reference for further research on the biological function of D . delavayi MADS -box gene family from the perspective of molecular evolution.

Objective To observe the correlation of stromal cell-derived factor 1 (SDF-1) with bone marrow mesenchymal stem cell (BMSCs) migration and airway inflammation in asthmatic rats. Methods Twenty-four clean SD rats were randomly divided into normal control (NC) group, model control (MC) group, and BMSCs group. Asthma model was established by OVA. In the BMSCs group, 1×10 6 BMSCs (1 mL) were transplanted into the tail vein on the day the model was completed. Pathological changes in lung tissues were evaluated by HE staining. The count of inflammatory cells in bronchoalveolar lavage fluid(BALF) was evaluated by Wright-Giemsa staining. The concentrations of IL-4, IL-5, IL-13, IgE, IgG1 and IgG2a in BALF were tested by ELISA. The expression of SDF-1 and STAT6 mRNA in lung tissue was measured by real time quantitative PCR. The expression of SDF-1 protein in bronchial epithelial cells were evaluated by Immunofluorescence staining. The expression of SDF-1 and STAT6 protein in lung tissue were measured by Western blot analysis. Results Compared with the normal group, the number of relative inflammatory cell counts and the concentrations of IL-4, IL-5, IL-13, IgE, IgG1, and IgG2a in BALF of the MC group increased significantly. The mRNA and protein expression of SDF-1 and STAT6 in lung tissue increased significantly. Compared with the MC group, inflammatory cells and inflammatory cytokines of BALF of BMSCs group were decreased in numbers, as was the expression of SDF-1 and STAT6 in lung tissues. Compared with the MC group, the expression of SDF-1 gene in lung tissues was increased, as was the expression of SDF-1 protein in bronchial epithelial cells. Conclusion In the process of asthmatic inflammation, the expression of chemokine SDF-1 in the damaged site increases, and promotes the migration of exogenous BMSCs to the lung tissue of asthmatic rats. BMSCs can regulate immune imbalance of Th1/Th2 cells by homing to damaged lung tissue, thus inhibiting asthmatic airway inflammation.

Docynia longiunguis is a plant uniquely present in China and is of high edible and medicinal value. The analysis of its chloroplast genome will help clarify the phylogenetic relationship among Docynia and facilitate the development and utilization of D. longiunguis resources. Based on the alignment of chloroplast genome sequences of related species, the phylogeny and codon preference were analyzed. The total length of D. longiunguis chloroplast genome sequence was 158 914 bp (GenBank accession number is MW367027), with an average GC content of 36.7%. The length of the large single-copy (LSC), the small single-copy (SSC), and inverted repeats (IRs) are 87 020 bp, 19 156 bp, and 26 369 bp, respectively. A total of 102 functional genes were annotated, including 72 protein-coding genes, 26 tRNA genes, and 4 rRNA genes. The best model for constructing phylogenetic tree was TVM+F+R2. D. longiunguis and Docynia indica were clustered into a single group, while Docynia and Malus were clustered into a single group. Comparison of the chloroplast genome sequences of D. longiunguis and its five related species revealed that trnY (GUA)-psbD , ndhC-trnV (UAC) , accD-psaI , psbZ-trnfM (CAU) , ndhF-trnL gene regions varied greatly. The nucleic acid diversity analysis showed that there were 11 high variation areas with nucleotide variability > 0.01, all were located in the LSC and SSC regions. Except for D. longiunguis , the trnH genes in other sequences were located at the IRs/LSC junction and did not cross the boundary. Codon preference analysis showed that D. longiunguis chloroplast genome has the largest number of isoleucine (Ile) codons, up to 1 205. D. longiunguis has the closest genetic relationship with Malus baccata , Malus sieboldii , Malus hupehensis and Chaenomeles sinensis . Its chloroplast genome codon prefers to end with A/T. The chloroplast genome of D. longiunguis and other Rosaceae chloroplast genomes showed great differences in gene distribution in four boundary regions, while relatively small differences from the chloroplast genomes of Docynia delavayi and D. indica of the same genus were observed. The genome annotation, phylogenetic analysis and sequence alignment of chloroplast genome of D. longiunguis may facilitate the identification, development and utilization of this species.

To explore the mechanism of acupoint embedding for obesity based on the western pathological mechanism of chronic low inflammatory response inducing the imbalance between"promoting inflammation"and"anti-inflammation"in immune reaction, and the pathological nature of deficient healthy qi and state of evil domination in the TCM theory induced by the"stagnation heat, phlegm heat, dampness heat, stasis heat"on the basis of qi deficiency. The mechanism may be improving the secretory disorder of adipose tissue and metabolic inflammatory response by the enhanced anti-inflammatory phagocytosis clearance ability in the immune system which is caused by the new inflammatory reaction under the stimulation of innate immune response pattern. The model of"inhibiting chronic low inflammation reaction through the innate immunity"may be an important mechanism of acupoint embedding for obesity.

The widespread application of next generation sequencing (NGS) in clinical settings has enabled testing, diagnosis, treatment and prevention of genetic diseases. However, many issues have arisen in the meanwhile. One of the most pressing issues is the lack of standards for reporting genetic test results across different service providers. The First Forum on Standards and Specifications for Clinical Genetic Testing was held to address the issue in Shenzhen, China, on October 28, 2017. Participants, including geneticists, clinicians, and representatives of genetic testing service providers, discussed problems of clinical genetic testing services across in China and shared opinions on principles, challenges, and standards for reporting clinical genetic test results. Here we summarize expert opinions presented at the seminar and report the consensus, which will serve as a basis for the development of standards and guidelines for reporting of clinical genetic testing results, in order to promote the standardization and regulation of genetic testing services in China.

Objective: To explore the generation pattern and clinical relevance of de novo HLA-DQ antibodies in renal transplantation., Methods: A total of 175 primary renal transplant recipients without pre-transplant HLA antibodies were recruited from January 2012 to December 2013. The average follow-up period was 10 (6-18) years. They were divided into control group (n = 94) with normal renal graft function (serum creatinine <120 µmol/L); dysfunction group (n = 54) with continued serum creatinine >150 µmol/L over 6 months; and graft loss group (n = 27) with resumed hemodialysis. The sera were collected and screened for de novo HLA antibodies by flow PRA or Luminex mixed beads. And HLA-A, -B, -DR and -DQ specific antibodies were identified by HLA single antigen beads., Results: Positive de novo HLA antibodies were detected in 48% (26/54) of patients from dysfunction group and in 52% (14/27) from graft loss group, but only in 17% (16/94) from control group (P < 0.01). The frequency of de novo DQ antibodies among patients with any positive HLA antibody was the highest in all three groups (14/16, 24/26 and 14/14). Additionally, the average mean peak fluorescence intensity of DQ antibodies was almost the highest when compared to other antibodies. Moreover, when those with positive HLA antibodies in each group were analyzed, 10/16 in control group were detected to have DQ antibodies alone. However, 17/26 of patients in dysfunction group and 14/14 in graft loss group were detected to have DQ antibodies plus HLA-DR and/or -A, -B antibodies. It indicated that the combined presence of DQ-and non-DQ- antibodies was associated with chronic renal graft failure., Conclusions: The presence of de novo HLA-DQ antibodies is frequent after renal transplantation. And it is associated with chronic graft failure when co-displaying with other HLA antibodies. The screening and detection of HLA-DQ antibodies after kidney transplantation may aid early warning of donor antigen-specific activation of immune system and subsequent graft dysfunction. Thus it serves as an indication for early treatment.

Objective: To compare the temporomandibular joint changes in adolescent Class II division 1 malocclusion patients with mandibular retrusion treated with Twin- block and Class II elastics., Methods: Sixty Class II division 1 malocclusion patients with mandibular retrusion were divided into 3 groups (Twin- block group, Class II elastic group and control group, 20 patients in each group) randomly. Differences of condylar process morphology were compared using cone- beam CT (CBCT) before and after treatment., Results: Condylar largest anteroposterior diameter and upper condylar height increased after treatment in both Twin-block group and Class II elastic group. The condylar largest anteroposterior diameter and upper condylar height were longer in both Twin- block group [(8.51 ± 1.48) and (7.39 ± 1.42) mm] and Class II elastic group [(8.44 ± 1.03) and (7.24 ± 0.89) mm] than those in the control group [(7.47 ± 1.27) and (6.47 ± 1.56) mm] (P<0.05). No significant difference was found in other measurements (P>0.05)., Conclusions: Condylar largest anteroposterior diameter and upper condylar height in Class II division 1 malocclusion patients increased after treatment using Twin- block and Class II elastics. There was no significant difference between two groups.

Objective: The aim of this study was to isolate bacterial strains with high-efficiency to degrade resins., Methods: We used resin-plate to isolate resin-degrading bacteria from the formation water of Nanbao35-2 oil field, China National Offshore Oil Corporation. The morphological properties and the sequence homology of 16S rRNA were used to identify the strains. The changes of four fractions contents and the infrared spectrometry of the heavy oil were used to analyze the degradation properties., Results: Four strains, Q4, QB9, QB26 and QB36, were isolated using resin as the sole carbon source. Based on the high sequence similarities (more than 99%) of 16S rDNA sequences analysis. These strains were identified as member of the Petrobacter sp., Geobacillus stearothermophilus, Bacillus licheniformis, Geobacillus pallidus, respectively. QB26, a Bacillus licheniformis, was the most efficient strain, it can grow well under anaerobic conditions, emulsify heavy oil well, and degrade resin and asphaltene in heavy oil. The relative content of saturated hydrocarbons in heavy oil increase after degradation, and the relative content of resin and asphaltene in heavy oil decreased 5.1% and 2.7%, respectively., Conclusion: The strains isolated from Nanbao 35-2 oil field formation water could degrade resin and heavy oil. They have potential values in microbial enhanced oil recovery and oil pollution treatment.

Objective: The diversity of culturable lipase-producing bacterial strains from permafrost soils at the terminus of a glacier in the Tianshan Mountains was investigated. Isolation and molecular phylogenetic analysis were performed to expand our knowledge on diversity of psychrotrophic and psychrophilic bacteria. In addition, efforts were made focusing on screening for cold active lipases., Methods: Lipase-producing bacterial strains were detected on tween 80 and olive oil plates, respectively. Identity and genetic diversity of strains isolated were determined by spatial 16S rRNA gene sequences and rep-PCR fingerprint. The physiological tests were carried out to determine the phonotypic differences between strains showing high similarity of 16S rRNA gene sequences., Results: Of the total 17 bacterial stains exhibiting cold-adapted lipase activity, we found that only 8 stains were able to hydrolyze olive oil. Based on 16S rRNA gene sequences, the lipase-producing bacterial isolates fell in five phylogenetic groups: subclasses (, ( and ( of Proteobacteria, Actinobacteria, and the Cytophaga-Flexibacter-Bacteroides (CFB) phylum. Nearly 59% of the isolates were affiliated with the genus Pseudomonas., Conclusion: The results enrich our knowledge on the psychrotrophic bacterial diversity and biogeographic distribution of cold active lipases-producing bacteria in cold environments.

Strains producing biological surfactants were isolated from formation water of Daqing oil field, Heilongjiang Province, China. From which a lipopeptide producing strain ZW-3 was screened out by PCR of the sfp gene. The morphology, cultural characteristics, physiological, biochemical properties and chemotaxonomy of strain ZW-3 were studied. The strain is rod shaped (0.7-0.8 microm x 2-3 microm), gram-positive, spore-forming and aerobic bacteria. Its (G+C) content was determined to be 42.2 mol%. Phylogenetic analysis based on 16S rRNA gene sequence demonstrated that it was closely related to the genus Bacillus subtilis, and the metabolites of strain ZW-3 was analyzed by thin layer chromatography and high performance liquid chromatography, the result indicated that the biosurfactant strain ZW-3 produced was surfactin. It could reduce surface tension of bacterial fermentation culture medium and water/oil- interfacial tension from 68.82 mN/m to 24.88 mN/m and from 23.53 mN/m to 4.57 mN/m, respectively, and its mixture with 1.8% NaOH could reduce water/oil- interfacial tension to an ultra low level (1.2 x 10(-3) mN/m), Its critical micelle concentration (CMC) was tested to be 33.3 mg/L (3.24 x 10(-5) mol/L)at 25 degrees C, and it had excellent emulsifying (2.89U) and foaming property. All these results showed that this biosurfactant had great potential in pharmaceutics, environmental protection, cosmetic, oil recovery and many other application fields.

Objective: To explore the biological reaction of swine acellular dermal matrix as a filling material for body surface deformity., Methods: Xenogenic acellular dermal matrix was implanted into the hypoderm of rabbits. The implants were measured and observed with pathological and transmission electron microscopic technique at regular times. The results were compared with implantation of autologous dermis and swine dermis., Results: The implanted xenogenic acellular dermal matrix and autologous dermis had slight inflammatory reaction. At 2 weeks there were fibroblasts and capillaries in the implants. The absorptivity of the xenogenic acellular dermal matrix was lower than the swine dermis. The xenogenic acellular dermal matrix was used in 2 clinical cases and obtained good result., Conclusion: The xenogenic acellular dermal matrix is an ideal material with good compatibility feature and low absorptivity.