Search

Sudden transition is a widely existing phenomenon in engineering practice. When the state of the system experiences sudden abrupt transition, calculus-based traditional mathematical modeling methods has low accuracy. Although theoretically, machine learning algorithms, such as artificial neural networks, can approximate any nonlinear function, this type of black-box method makes no reasonable explanation for the sudden transition phenomenon. The cusp catastrophe model based on the catastrophe theory can be applied to explain the discontinuous changes in the system’s state. However, the construction of traditional cusp catastrophe models is often based on large amounts of prior knowledge to select the input variables for modeling. On the condition that there is a lack of prior knowledge and comparatively large dimensions of input variables, the model has high complexity and poor accuracy. In this paper we have put forward a two-step method for constructing a cusp catastrophe model based on the selection of variables to solve the abovementioned problems. The first step was to apply multimodel ensemble important variable selection (MEIVS) to quantify the importance of the variables to be selected and extract important variables. The second step was to use the extracted important variables to construct a cusp catastrophe model based on the framework of maximum likelihood estimation (MLE). Results indicate that on a dataset with characteristics of catastrophe, the cusp catastrophe model is simple in form using the MEIVS dimensionality reduction algorithm and outperforms the unreduced cusp catastrophe model and reduced cusp catastrophe model using other dimensionality reduction algorithms in terms of evaluation indicators. This shows that the algorithm proposed in this paper have improved the accuracy and reduced the complexity of the cusp catastrophe model. At the same time, the cusp catastrophe model exhibits higher accuracy compared with the linear and logistic models. Thus, it can be used to explain the discontinuous changes of the research object, and it has a practical engineering significance.

In this study, the defects in the wall of petroleum casing steel pipe were investigated. The morphology and composition of inclusions in the defects of the steel pipe were analyzed using scanning electron microscopy–energy-dispersive X-ray spectroscopy. The thermodynamic calculation of the Ca‒Al equilibrium phase diagram of molten steel in tundish and the changes of the ladle slag phase composition with cooling temperature was performed using FactSage8.0. The results show that the longitudinal surface of the defect is mainly composed of shallow and deep stripes. A large number of MgO·Al2O3 inclusions containing a small amount of Mn is detected at shallow stripes, and a large number of inclusions, such as Al2O3, MgO·Al2O3, and CaO·Al2O3·SiO2 are detected at deep stripes. The three main types of inclusions in the cross-section of the defect zone are CaO·Al2O3·SiO2, CaO·Al2O3·MgO, and CaO·Al2O3·MgO·SiO2. According to the analysis results of inclusions in the cross-section and the calculation results of the phase transformation of slag droplets during solidification and cooling, the formation mechanism of the defects in the wall of steel pipe can be speculated as follows: (1) At the end of pouring, the ladle slag in molten steel in the ladle enters the tundish. Further, the slag droplets adsorb the fine xAl2O3·yCaO or Al2O3 inclusions with high Al2O3 content in molten steel, increasing the Al2O3 and CaO contents in the slag droplets. (2) Ladle slag in molten steel is subjected to strong stirring in Ar gas in the vacuum degassing (VD) refining process. Moreover, the slag droplets adsorb the fine Al2O3 inclusions in molten steel, increasing the Al2O3 content in the slag droplets. During solidification and cooling, the slag droplets formed in the two aforementioned forms of inclusions are transformed into three types of inclusions: CaO·Al2O3·SiO2, CaO·Al2O3·MgO, and CaO·Al2O3·SiO2·MgO. In the process of round billet piercing deformation, under the action of longitudinal tensile stress and transverse shear stress, the large slag droplets involved extend along the longitudinal cross-section and finally form defects in the wall of the steel pipe.

Based on the background of engineering education certification, the course objectives of “Food Processing Machinery and Equipment” were optimized by integrating the concept and standard of engineering education certification and the major training objective of Food Science and Engineering. Taking the course assessment results of 6 classes in one academic year as an example, the achievement of course objectives and the existing problems in the course of “Food processing Machinery and Equipment” were analyzed, then some suggestions on teaching reform including course objectives, teaching content, teaching methods and assessment and other aspects were proposed, so as to improve the degree of achievement of course objectives and guarantee the teaching effect.

In order to understand the concentration decay law of sulfuryl fluoride fumigation in warehouses with different airtightness,five warehouses were selected in this experiment.Through the concentration monitoring during the fumigation process,the correlation between the decay half-life of the gas concentration and the air tightness of the warehouses is analyzed and compared.The results show that when the airtightness of the warehouse is 143 s,the maximum concentration half-life is 8.5 d,while with the airtightness of 53 s and 46 s,the maximum concentration half-life are 2.7 d and 4.6 d,respectively.The half-life of gas concentration in warehouses where air-tightness cannot be detected is about 2～3 d.The higher the concentration of sulfuryl fluoride gas,the faster the decay speed,however the concentration decay process does not show a certain connection with the air tightness of the warehouses.

To understand the diffusion and distribution of sulfuryl fluoride in wheat,rice and soybean piles,experiments were carried out in 6 warehouses to compare and analyze the diffusion speed,uniformity,and attenuation speed of fumigant gas in different grain piles.Data were collected in the process of fumigation.Experiment results show that the diffusion rate of sulfuryl fluoride gas in different grains is quickest in the soybean pile,followed by the rice pile and wheat pile:the soybean pile can achieve uniform gas in its warehouse as soon as 8 hours after fumigation.The average gas concentration half-life is longest in the soybean pile,shortest in the rice pile with the wheat pile stands in the middle:the fumigation concentration of 5.0～12.7 g/m3 can safeguard an insect-free environment for 6 months.

Because the thermal conductivity of freezing soil is hard to measure, in order to clarify the influence of temperature on thermal conductivity, a hyperbolic model with three parameters was proposed to describe the relationship between thermal conductivity and negative temperature in this paper. Then, the performance of the new hyperbolic model was verified by the measured thermal conductivity coefficients and three widely used models, and a sensitivity analysis of model parameters was performed. The results show that the hyperbolic model can accurately predict the change pattern of soil thermal conductivity during the freezing process. Among these four models, the proposed hyperbolic model has the smallest root mean square error and relative error. The model parameters are closely related to the fine particle content and decrease as the initial volume moisture content increases. Considering the new model can accurately simulate the variation of thermal conductivity with subzero temperature, it can provide a basis for coupled heat and mass transfer in cold regions. [ABSTRACT FROM AUTHOR]

The stress corrosion cracking (SCC) behavior and mechanism of M152 and 17-4PH high-strength steels in high Cl- environment were studied through neutral salt spray test and slow strain rate tensile (SSRT) test. The result shows that M152 and 17-4PH steels exhibit a certain sensitivity to SCC in Cl- environment, elongations of them both decrease with the increasing time of early neutral salt spray test, and the SCC sensitivity gradually increases. Comparing the fracture morphology with lateral crack through SEM, it can be found that the fracture mechanism of M152 and 17-4PH high-strength steels converts ductile fracture to brittle fracture as the extension of neutral salt spray test time. The synergistic effect of anodic dissolution (AD) and hydrogen embrittlement (HE) result in the occurrence of SCC in high Cl- environment, and Cl- can promote the AD process. Due to the obvious effect of HE, 17-4PH steel has higher SCC sensitivity than M152 steel with the same time of early neutral salt spray test. 17-4PH high-strength steel is more prone to SCC than M152 in high Cl- environment.

The experiment was to explore the effect of prenatal feeding of compound Chinese herbal medicine preparation on the abortion rate and lambing rate of Hu sheep. A total of 2 100 ewes in late pregnancy were selected and randomly divided into two groups. Test group consisted of 1 100 ewes with 11 replicates, 100 sheep in each replicate. Control group was consisted of 1 000 ewes with 10 replicates and 100 sheep in each replicate. The sheep in control group were fed with basic feed, and sheep in test group were fed with test feed supplemented with 5 mL/head compound Chinese herbal medicine preparation for 10 d. The results showed that compared the control group, the abortion rate in test group was significantly reduced ( P<0.05). Compared with control group, the weak lambing rate and paralyzed sheep rate in test group were significantly reduced ( P<0.05). Compared with control group, the lamb mortality of test group was significantly reduced ( P<0.05), and the cure rate was significantly increased ( P<0.05). Compared with control group, the single tire weight, twin weight and triple tire weight were significantly increased ( P<0.05). The study indicates that the addition of 5 mL/head compound Chinese herbal medicine preparation to feed can improve the number of abortions, weak sheep and paralyzed sheep of pregnant ewes, and increase the lambing rate and the cure rate of lambs. [ABSTRACT FROM AUTHOR]

Multi-walled carbon nanotubes (MWCNTs) were treated with dopamine coating to obtain modified MWCNTs (PDA@MWCNTs). Fe3O4 was deposited on the surface of MWCNTs to prepare Fe3O4@PDA@MWCNTs. SR/Fe3O4@PDA@MWCNTs composites were prepared by mixing liquid silicone rubber (SR) with Fe3O4@PDA@MWCNTs. The results show that the content of Fe element on the surface of Fe3O4@PDA@MWCNTs reaches 1.11%. The average particle size of Fe3O4 on the surface of MWCNTs after loading is 27.28 nm. With the increasing of Fe3O4@PDA@MWCNTs content, the thermal conductivity of the composites increases and the thermal stability decreases. When the filler content is 100 phr, the initial decomposition temperature of the composite is 284 °C, and the thermal conductivity is 0.432 1 W/(m⋅K), which is 73.5% higher than that of pure SR. After 200 s heating, the surface temperature of the composite material reaches 42.3 °C, which has good thermal conductivity and meets the requirements of CPU heat dissipation components. [ABSTRACT FROM AUTHOR]

Combined with the practical engineering case, we analyzed the damage reason of floating oil seals and put forward the measures of improvement. There is great significance for improving the service life of the equipment and environment protection. [ABSTRACT FROM AUTHOR]

[objective] Effects of single-stage and multi-stage drum drying on drying efficiency and aroma quality of flue -cured cut tobacco were investigated to provide references for optimization and application of multi -stage drying process. [Method]A kind of C2F cut tobacco was dried by using the lab-scale drum device. Effects of different drying methods and temperatures on drying efficiency, petroleum ether extract and aroma components were analyzed and compared. [Result]Compared with single stage drum drying (110 °C ), the multi-stage drum drying effectively shortened the drying time and dehydration efficiency increased by 5%-15%. For two kinds of drying methods, petroleum ether extract content decreased with the increase of cylinder wall temperature. The contents of aroma components, brown reaction products and carotene degradation products showed the same variations. Multi-stage drum drying led to higher contents of petroleum ether extract and aroma components in cut tobacco than the 120-140 °C of single stage drum drying at high temperature. And aroma components went up by 12%. Under the condition of 120/110 °C multi-stage drum drying, the contents of aroma components, petroleum ether extract, brown reaction products and carotene degradation products reached the highest level. [Conclusion]Compared with single stage drum drying, 120/110°C of multi-stage drum drying is more beneficial for both the aroma quality and dehydration efficiency of flue -cured cut tobacco, thus it can be applied in the flue-cured cut tobacco dying process. [ABSTRACT FROM AUTHOR]

[ Objective ]The drying and shrinkage characteristics of cut tobacco during drum drying with combined heat transfer were investigated to provide references for drying process optimization. [ Method ] A kind of B2F cut tobacco was dried under the different drum temperatures, and the moisture content, temperature and shrinkage of cut tobacco were investigated during drying. [ Result ] Drying kinetics of cut tobacco could be described by the Weibull model, which had a fitting accuracy higher than 0.9700. The drum temperature had a significant effect on the constant drying stage and rapid heating stage of cut tobacco. Higher drum temperature resulted in higher dehydration rate as well as rapider heating rate. The volume shrinkage rate of cut tobacco showed a linear relationship with moisture content. At the drying end, the shrinkage rate of cut tobacco was up to 20%-25%. [ Conclusion ]The drum temperature proves to be an key element influencing the drying effects, hence it should be regarded as the first parameter for drying process of cut tobacco. [ABSTRACT FROM AUTHOR]

Lysophosphatidic acid acyltransferase (LPAAT) which converts lysophosphatidic acid into phosphatidic acid is a key enzyme in biosynthesis pathway of lipid in plants. In this study, we identified 17 members of the LPAAT gene family from genomic data of G. raimondii-D5 and G. arboreum-A2. Analysis of gene structure, chromosome distribution and phylogenetic evolution of LPAAT genes in diploid Gossypium using bioinformatics approaches showed that these genes can be divided into distinct subfamilies based on the distance of their genetic relationship. Moreover, the gene structures were similar within LPAAT subfamily members. The amino acid sequences encoded by LPAAT family genes contained three conserved motifs, including ΦFPEGTR-G binding site and Φ-NHQS- ΦDΦΦ catalytic site. Phylogenetic analysis of LPAAT gene family demonstrated significant differences in evolution of LPAAT in different species. Finally, expression analysis of G. hirsutum ovules in different stages from RNA-seq and qRT-PCR data indicated that LPAAT gene may play a positive role in oil accumulation. Our studies facilitate understanding of the function of LPAAT gene family in Gossypium and selecting better LPAAT genes for further functional validation.

Within the drainage basin, information about natural processes and human activities can be recorded in the chemical composition of riverine water. The analysis of the Guijiang River, the first level tributary of the Xijiang River, demonstrated that the chemical composition of water in the Guijiang River was mainly influenced by the chemical weathering of carbonate rocks within the drainage basin, in which CO2 was the main erosion medium, and that the weathering of carbonate rock by H2SO4 had a remarkable impact on the water chemical composition in the Guijiang River. Precipitation, human activities, the weathering of carbonate rocks and silicate rocks accounted for 2.7%, 6.3%, 72.8% and 18.2% of the total dissolved load, respectively. The stable isotopic compositions of dissolved inorganic carbon (delta13C(DIC)) indicated that DIC in the Guijiang River had been assimilated by the phytoplankton in photosynthesis. The primary production of phytoplankton contributed to 22.3%-30.9% of particulate organic carbon (POC) in the Guijiang River, which implies that phytoplankton can transform DIC into POC by photosynthesis, and parts of POC will sink into the bottom of the river in transit, which leads into the formation of burial organic carbon.

Objective: To retrospectively analyze the bacteriological spectrum and drug susceptibility of pus flora from abdominal traumatic patients with severe intra-abdominal infection., Methods: A total of 41 severe intra-abdominal infected patients with abdominal trauma were recruited to collect 123 abdominal pus specimens. And the results of laboratory microbiology and drug sensitivity were analyzed with the WHONET 5.4 software., Results: A total of 297 strains of bacteria were isolated at (7.2 ± 2.3) strains for each patient. Gram-positive bacteria accounted for 44.1% (131/297) , Gram-negative bacteria 55.2% (164/297) and fungi 0.7% (2/297). The top five isolates were Escherichia coli, Staphylococcus aureus, Klebsiella pneumonia, Enterococcus faecalis and Pseudomonas aeruginosa. Those antibiotics highly sensitive (>90%) to Escherichia coli included cefoperazone (91%), imipenem (98%); highly sensitive to Gram-positive cocci included teicoplanin (100%) and linezolid (100%). Staphylococcus aureus was 100% sensitive to vancomycin. The agents with a high susceptibility to Klebsiella pneumonia included imipenem (100%) and amikacin (79%). Ciprofloxacin (90%) had the highest sensitivity to Pseudomonas aeruginosa., Conclusions: The predominant bacteria of causing severe intra-abdominal infection of traumatic patients is Gram-negative bacteria, but the infection of Gram-positive bacteria, especially the ratio of Staphylococcus aureus infection is also comparatively high. Cefoperazone, ciprofloxacin, imipenem, vancomycin, teicoplanin and linezolid have higher antibacterial activity.

Objective: To evaluate the effect of FLAMIGEL (hydrogel dressing) on the repair of residual burn wound., Methods: Sixty burn patients with residual wounds hospitalized in 6 burn units from November 2011 to May 2012 were enrolled in the multi-center, randomized, and self-control clinical trial. Two residual wounds of each patient were divided into groups T (treated with FLAMIGEL) and C (treated with iodophor gauze) according to the random number table. On post treatment day (PTD) 7 and 14, wound healing rate was calculated, with the number of completely healed wound counted. The degree of pain patient felt during dressing change was evaluated using the visual analogue scale (VAS). The mean numbers of wounds with score equal to zero, more than zero and less than or equal to 3, more than 3 and less than or equal to 6, more than 6 and less than or equal to 10 were recorded respectively. Wound secretion or exudate samples were collected for bacterial culture, and the side effect was observed. Data were processed with repeated measure analysis of variance, t test, chi-square test, and nonparametric rank sum test., Results: Wound healing rate of groups T, C on PTD 7 was respectively (67 ± 24)%, (45 ± 25)%, and it was respectively (92 ± 16)%, (72 ± 23)% on PTD 14. There was statistically significant difference in wound healing rate on PTD 7, 14 between group T and group C (F = 32.388, P < 0.01). Ten wounds in group T and four wounds in group C were healed completely on PTD 7, with no significant difference between them (χ(2) = 0, P > 0.05). Forty-two wounds in group T and seven wounds in group C healed completely on PTD 14, with statistically significant difference between them (χ(2) = 42.254, P < 0.01). Patients in group T felt mild pain during dressing change for 37 wounds, with VAS score higher than zero and lower than or equal to 3. Evident pain was observed in patients of group C during dressing change for 43 wounds, and it scored higher than 3 and less than or equal to 6 by VAS evaluation. There was statistically significant difference in mean number of wounds with different grade of VAS score between group T and group C (Z = -4.638, P < 0.01). Staphylococcus aureus, Pseudomonas aeruginosa, Klebsiella pneumoniae, E. coli, Baumanii, and Staphylococcus epidermidis were all detected in both groups, but there was no statistical difference between group T and group C (χ(2) = 0.051, P > 0.05). No side effect was observed in either of the two groups during the whole trial., Conclusions: FLAMIGEL can accelerate the healing of residual burn wounds and obviously relieve painful sensation during dressing change.

Objective: To investigate the molecular subtypes of 73 strains of Yersinia enterocolitica biotype 1A isolated in Shandong province by PFGE, and thereby to analyze the relationship between PFGE typing and biological characteristics., Methods: Seventy-three strains of Yersinia enterocolitica biotype 1A were isolated from animal feces and meat products in Gaomi city and Wulian county in Shandong province from 2008 to 2009. Motility test, serum agglutination and virulent genes detection by PCR were used to learn the biological characteristics of the isolated strains. The molecular subtypes were determined by PFGE, whose relationships with motility, serotypes and virulent genotypes were also analyzed., Results: Out of the 73 strains of Yersinia enterocolitica, 5 showed medium-active motility while the other 68 showed well-active motility. The dominated serotypes were O:5(17/73) and O:8(14/73), followed by O:9(5/73) and O:7, 8(1/73), and there was no O:3 serotype found. Meanwhile, 36 strains couldn't be serotyped. All the strains were negative with the gene ail, ystA, yadA and virF, yet the positive rate of ystB gene was 72.6% (53/73). The 73 strains of Yersinia enterocolitica isolated could be subtyped into 54 PFGE patterns (K6GN11SD0001-K6GN11SD0054), most of which only had 1 or 2 isolated strains, and no pattern was dominant. The strains in the same or similar cluster were from different hosts; each serotype and toxic genotype scattered in the clustering trees, without specific correlation with PFGE subtypes. 4 out of 5 strains, which showed medium-active motility, belonged to one branch, with the similarity coefficient at 80.9% - 100.0%; while all the toxic genotype belonged to type B., Conclusion: Biotype 1A Yersinia enterocolitica has many clones, whose PFGE types had relations with motility, but no relations with virulent genotype and host.

Objective: To investigate the etiology and clinical characteristics of hospital-acquired pneumonia (HAP) in China and to provide evidence for appropriate therapy., Methods: We performed a prospective multicenter study in 13 Chinese urban tertiary hospitals. All HAP cases diagnosed at respiratory general ward and respiratory intensive care unit (RICU) from August 2008 to December 2010 were studied. Epidemiological data, etiology and clinical characteristics of enrolled patients were collected. Sputum or tracheal aspirate and blood cultures, Legionella antibodies and Streptococcus pneumoniae urinary antigen tests were performed. Bacteria to antimicrobial susceptibility test was performed., Results: A total of 610 cases of HAP were diagnosed during the study, with an overall incidence of 1.4% among 42 877 hospitalized patients, while the incidence was 0.9% (362/41 261) in respiratory general ward and 15.4% (248/1616) in RICU. 93.9% (573 cases) of patients had at least one underlying disease, and 91.0% (555 cases) had exposure to at least one antimicrobial agent within 90 days prior to HAP diagnosis. Pathogens were identified in 487 patients, with Acinetobacter baumannii [30.0% (183/610)], Pseudomonas aeruginosa [22.0% (134/610)], Staphylococcus aureus [13.4% (82/610)] and Klebsiella pneumonia [9.7% (59/610)] being the most common pathogens. Eighteen patients (3.0%) had infection with fastidious bacteria. A. baumannii and S. aureus were the more frequent pathogens in the ventilator-associated pneumonia (VAP) cases [50.5% (97/192) and 21.4% (41/192)] as compared to non-VAP cases [20.6% (86/418) and 9.8% (41/418), P < 0.01]. A. baumannii and S. aureus were also frequent pathogens in cases with a score of more than 20 by the acute physiology and chronic health evaluation II (APACHEII) scoring [45.7% (69/151) and 20.5% (31/151)], as compared to cases with a score of less than 20 of APACHE II [24.8% (114/459) and 11.1% (51/459), P < 0.01]. A. baumannii showed high resistance rates to carbapenems [more than 70% (109/142)], and the susceptibility to cefoperazone/sulbactam, polymyxin B and tigecycline were 40.8% (58/142), 99.3% (141/142) and 95.8% (136/142) respectively. Resistance rates of P. aeruginosa to meropenem and imipenem were 48.8% (40/82) and 70.7% (58/82) respectively. Methicillin-resistant S. aureus (MRSA) accounted for 87.8% (43/49) in all strains of S. aureus. Mortality rate of VAP cases was 34.5% (61/177), significantly more than that of HAP patients [22.3% (135/605), P < 0.05]. The average hospital stay of patients with HAP was (23.8 ± 20.5) days, significantly more than that of the average for inpatients [(13.2 ± 13.6) days, P < 0.01] during the study period. Mean costs of HAP were (108 950 ± 116 608) yuan, significantly higher than the average hospital costs of respiratory inpatients (17 999 ± 33 364) yuan., Conclusions: Among Chinese patients hospitalized in urban tertiary medical centers, HAP incidence and mortality rate were high, which increased the patients' hospital stay and the medical costs. Common pathogens were A. baumannii, P. aeruginosa, S. aureus and K. pneumonia. The common bacteria of HAP in China showed high resistance rates to antibiotics.

Objective: To observe the expressions of nerve growth factor (NGF) and its tyrosine kinase A (TrkA) receptor on alveolar macrophage in a rat model of chronic obstructive pulmonary disease (COPD)., Methods: Forty healthy male SD rats were randomly divided into a control group and a COPD group. The COPD model was established by exposing the rats to cigarette smoke for 6 months, and lung function changes were measured. Lung histopathological changes were detected by HE staining. The expression of NGF protein in the supernatant of alveolar macrophage (AM) culture medium was detected by ELISA. Confocal microscopy was used to identify the separation and purification of AM from bronchoalveolar lavage fluid, and to detect semi-quantitatively the expression of TrkA receptor on AM. NGF and its TrkA receptor at the mRNA level were evaluated by real-time PCR. The differences among groups were calculated by one way ANOVA, and comparison between groups was made by t test., Results: Significant decrease of pulmonary compliance [(0.15 ± 0.03) ml/cm H(2)O (1 cm H2O = 0.098 kPa)] and minute ventilation [(0.045 ± 0.004) L], and significant increase of airway resistance [(0.038 ± 0.004) cm H2O×L(-1)×s(-1)] were found in the COPD group compared with the control group [(0.42 ± 0.05) ml/cm H2O and (0.102 ± 0.010) L and (0.016 ± 0.002) cm H2O×L(-1)×s(-1), t = 9.46 - 12.99, respectively, all P < 0.01]. Alveolar wall thinning, alveolar septa breakdown, alveolar enlargement and emphysema were significant in the COPD rats. The expression of NGF protein in the supernatant of AM culture medium was enhanced in the COPD group [(3.79 ± 1.52) ng/L] compared with the controls [(0.94 ± 0.27) ng/L, t = 4.13, P < 0.05]. Mean fluorescence intensity of TrkA protein on AM in the COPD group (19.5 ± 1.5) was higher than that in the control group (11.2 ± 1.9, t = 7.95, P < 0.05). The expressions of NGF and TrkA at mRNA level in the COPD group (24.8 ± 6.0 and 9.0 ± 3.3) were increased compared with the control group (1.0 ± 0.2 and 1.0 ± 0.4, t = 8.48 and 5.16, all P < 0.05)., Conclusions: The expressions of NGF and its TrkA receptor on AM in COPD group were increased, indicating that NGF and its TrkA receptor might be involved in the pathogenesis of COPD mediated by AM.

Objective: To assess the value of galactomannan (GM) double-direct sandwich enzyme-linked immunosorbent assay (ELISA) in the diagnosis of invasive aspergillosis (IA)., Methods: A search in MEDLINE, EMbase, OVID, CBMdisc and CHKD from Jan. 1991 to Dec. 2008 was conducted to collect all articles about diagnostic tests of serum GM detection. Then the methodological quality was assessed by QUADAS-items, sources of heterogeneity investigated, pooled effect quantities evaluated, and meta-analysis studies, SROC curves, and subgroup analysis performed., Results: Thirty-six articles with a population of 4959 patients were included. The average prevalence of IA was 10%(532/4959). Our meta-analysis reported a median heterogeneity (I(2) = 48.6%, P < 0.05), with a pooled DOR value of 19.10 (95%CI 12.67 - 28.79), a pooled sensitivity of 0.66 (95%CI 0.61 - 0.70), a pooled specificity of 0.90 (95%CI 0.89 - 0.90), a pooled positive likelihood ratio of 5.48 (95%CI 4.27 - 7.02), a pooled negative likelihood ratio of 0.38 (95%CI 0.29 - 0.50), and an area under curve of SROC 0.88. The rate of underdiagnosis of serum GM detection was 34% (168/490) and the rate of misdiagnosis was 10% (466/4469). With a rise in the cut-off value the sensitivity of GM test decreased and specificity increased. Two consecutive positive tests decreased the sensitivity but increased the specificity. Age had no significant effect on the diagnosis by GM test. Both antifungal prophylaxis and antifungal therapy had no significant effect on sensitivity and specificity of GM test for IA diagnosis., Conclusion: Serum GM detection is an effective diagnostic tool for invasive aspergillosis in high-risk populations.

Objective: To compare the clinical effectiveness of percutaneous US- or CT-guided drainage and laparotomy for patients with infective pancreatic necrosis., Methods: Data of 90 infective pancreatic necrosis patients admitted from January 2008 to December 2009 were included. They were divided into two groups by the different treatment choices. Twenty-seven patients in the percutaneous group received percutaneous US- or CT-guided drainage as first choice. After that a sump suction apparatus was applied for controlled drainage. If no improvement was achieved after 3 days, they would received operation soon. While patients in the laparotomy group received surgical drainage at the time when the diagnosis of infected pancreatic necrosis was confirmed. Continuous drainage was also applied for these ones., Results: The percutaneous group had a significant low rate of reoperation (7.1% vs. 14.3%, P < 0.05) and postoperative residual abscesses (7.1% vs. 28.6%, P < 0.05). Furthermore, 48.1% of patients in percutaneous group successfully avoid laparotomy. In the regard of complications, the percutaneous group presented lower incidence of both single organ dysfunction (7.4% vs. 28.6%, P < 0.05), intestinal fistula (7.4% vs. 27.0%, P < 0.05) and long-term complications (3.7% vs. 22.2%, P < 0.05). In addition, the percutaneous group costed less medical resources as evidenced by shorter ICU duration (21.2 ± 9.7 vs. 28.7 ± 12.1, P < 0.01), shorter hospital duration (48.2 ± 12.5 vs. 59.6 ± 17.5, P < 0.05) and less expenditure (191 762 ± 5892 vs. 341 689 ± 10 854, P < 0.05)., Conclusions: Percutaneous drainage can effectively lower the surgical rates and the rates of complications and reoperations in patients with infective pancreatic necrosis. Besides that, it could also reduce the cost of medical resources.

Objective: To summary the treatment experience of severe acute pancreatitis (SAP)., Methods: From January 1997 to March 2009, a total of 1033 patients suffered SAP were admitted with a mean APACHE II score 12.0 +/- 4.3. There were 622 males and 411 females, aged from 13 to 98 years old. All patients were cared by the multidisciplinary team with intensivist, endoscopists, gastroenterologists, radiologist, nephrologist and surgeons.Patients treated in SICU in the early phase of the disease. In these 1033 patients, 365 cases received mechanical ventilation, 218 with tracheotomy, 159 cases received high-volume continuous venovenous hemofiltration (CVVH), 179 received nasobiliary drainage, 513 were treated with early enteral nutrition. CT-guided percutaneous catheter drainge for peripancreatic fluid collection was pefromed for 477 times and 438 patients received surgical debridement for infected pancreatic necrosis., Results: In all these 1033 cases, 975 patients (94.4%) survived, and 38 patients died (3.7%). The mortality of patients who received surgical debridement for infected pancreatic necrosis was 7.1% (31/438)., Conclusion: The muti-discipline management of severe acute pancreatitis can remarkably improve the prognosis of patients.

Objective: To analyse the distribution, drug resistance and epidemiology of pathogenic bacteria in the burn wards of Ruijin Hospital., Methods: Seventeen strains of Methicillin resistant staphylococcus aureus (MRSA), 52 strains of Pseudomonas aeruginosa (PA), and 11 strains of Acinetobacter baumannii (AB) isolated from the wound secretion, venous catheters, blood, urine and stool etc. were collected from burn patients hospitalized in our department from January 2004 to December 2006. The distribution and the drug resistance profile of bacteria were analyzed, and the homology analysis was performed by randomly amplified polymorphic DNA (RAPD)., Results: MRSA, PA and AB were the major strains in our burn wards in recent years, of which Staphylococcus aureus (SA) was the most dominant. During these 3 years, MRSA accounted for 77% (63/82), 85% (63/74), and 75% (74/99), respectively, for SA isolated in this period. MRSA was resistant to Amikacin, Gentamicin, Erythromycin, Clindamycin and Levofloxacin; PA was resistant to Amikacin, Gentamicin, Piperacillin, Ceftazidime, Cefoperazone, Aztreonam and Imipenem; AB was resistant to Amikacin, Gentamicin, Piperacillin, Ceftazidime, Imipenem and Ciprofloxacin. Three bacteria were found to belong to the same type in the RAPD homology analysis., Conclusions: There are many kind of multi-drug resistant pathogenic bacteria for nosocomial infection in our burn wards. To control the spread of infection due to above-mentioned 3 bacteria is the focus of nosocomial infection control.

Objective: To study the features of liver damage caused by anti-TB medicines among patients with TB-HBV co-infection, in order to complement and improve the implementation of DOTs strategy in the region., Methods: A historical cohort study was conducted including the process of reviewing and analyzing files of the 781 naive TB patients hospitalized from June 2004 to October 2005. Cases were divided into HBsAg (+) group and HBsAg (-) group., Results: The overall damage rate among the 781 investigation cases was 20.74%, including 121 cases (74.69%) in HBsAg (+) group and 41 cases (25.31%) in HBsAg (-) group. Data showed that liver damage rate and average value of ALT and AST of HBsAg (+) group were higher than those in HBsAg (-) group. First case with liver damage in HBsAg (+) group happened on the 7th day of the treatment, while the first liver damage case happened in HBsAg (-) group was on the 16th day. The average onset in HBsAg (+) group was earlier than HBsAg (-) group for 18.09 days. The average time of liver function recovery in HBsAg (+) group was 57.02 days and in HBsAg (-) group it was 27.56 days while the appearance among HBsAg (+) group was 29.46 days later than in HBsAg (-) group., Conclusion: The incidence rate of liver damage caused by anti-TB medicines was higher among HBV positive patients than those HBV negative patients. Patients co-infected with HBV infection appeared to be more serious, with higher incidence on liver damage and earlier onset, as well as with the degree of damage to the liver.

Objective: To evaluate the effect of using dental operating microscope and ultrasonic instruments in treating blocked canals., Methods: The etiology of canal blockage included calcification, broken instruments, posts, resinifying, etc. 236 blocked canals were treated with ultrasonic tips under dental operating microscope. The success rate was calculated., Results: 178 blocked canals were successfully managed with a success rate of 75.4%. The success rate of each category of the blocked canals were: 71.7% for calcified canals, 81.1% for broken instruments, 100% for canals blocked by posts, 62.5% for canals blocked by resinifying therapy, and 84.1% for canals blocked by filling materials., Conclusion: The use of dental operating microscope and ultrasonic instruments is proved to be an effective method in the management of blocked canals.

Objective: To investigate the significance of T cell immunoglobulin domain and mucin domain-1 (TIM-1) expression in helper T lymphocyte in allergic rhinitis (AR) patients., Methods: Peripheral blood samples were collected from 20 AR patients, 9 males and 11 females, aged 31.4 (20-54), and 20 healthy persons, 12 males and 8 females, aged 38, 6 (18-60). Peripheral blood mononuclear cells (PBMNs) were isolated and magnetic cell sorting technique was used to purify the CD4+ T cells and CD4 + CD45RA + T cells. Immunofluorescence staining and flow cytometry were used to detect the percentage of CD4 + CD45RA + T cells positive in TIM-1, a helper T lymphocyte marker. Phytohemagglutinin (PHA) was added into the culture media to stimulate the TIM-1 positive helper T lymphocytes. Dendritic cells (DCs) thus induced and differentiated were conditioned by standardized allergen from dust mite (Dermatophagoides pteronyssinus) or lipopolysaccharide (LPS), and then co-cultured with CD4 T cells. The percentage of TIM-1 positive CD4 + CD45RA + T cells was counted. ELISA was used to detect the IL-4 and interferon (IFN)-gamma levels in the supernatants of the culture media of the dust mite and LPS groups., Results: The percentage of TIM-1 positive CD4+ T cells of the AR patients was (9.48 +/- 1.51)%, significantly higher than that of the healthy controls [(3.12 +/- 0.32)%, P < 0.05], and the percentage of TIM-1 positive CD4 + T cells after PHA stimulation of the AR patients was (47.05 +/- 4.35)%, significantly higher than that of the healthy controls [(29.92 +/- 3.36)%, P < 0.05]. The percentage of TIM-1 positive CD4 + CD45RA + T cells of the AR patients was (26.34 +/- 4.0)%, significantly higher than that of the healthy controls [(18.4 +/- 8.1)%, P < 0.05], and the percentage of TIM-1 positive CD4 + CD45RA + T cells after PHA stimulation of the AR patients was (65.3 +/- 7.4)%, significantly higher than that of the healthy controls [(36.3 +/- 6.8)%, P < 0.05]. The percentage of TIM-1 positive CD4 + CD45RA + T cells co-cultured with the DCs conditioned by dust mite of the AR patients was (10.81 +/- 1.48)%, significantly higher than that of the LPS group [(6.08 +/- 1.45)%] and the blank control group [(1.56 +/- 2.30)%, both P < 0.05]. The IL-4 level of the DCs conditioned by dust mite allergen was (74.61 +/- 13.82) pg/ml, significantly higher than those of the LPS group and blank control group [(28.57 +/- 3.36) and (1.40 +/- 0.99) ng/ml respectively, both P < 0.05]. The IFN-gamma level of the DCs conditioned by dust mite allergen was (25.31 +/- 7.23) pg/ml, significantly lower than that of the LPS group [(163.41 +/- 82.37) pg/ml, P < 0.05], however, significantly higher than that of the blank control group [(1.58 +/- 0.53) pg/ml, P < 0.05]., Conclusion: The percentage of TIM-1 positive helper T lymphocytes of the AR patients are abnormally high. After stimulation of allergen The DCs increase the number of TIM-1 expressing naïve Th cells and promote them to differentiate into Th2 cells. Promoting naïve Th cells to differentiate into Th2 cells, TIM-1 expression induces Th2 cytokine-based immune responses.

Objective: To investigate the protective effect of inhibition of stress (lytic cocktail) on lung injury in severe burn rats at early stage., Methods: Sprague-Dawley rats inflicted with 30% TBSA full-thickness burn were randomly divided into A group (n = 36, fluid resuscitation with administration of lytic cocktail), B group (n = 36, fluid resuscitation only). Lung function was evaluated by partial pressure of oxygen (PaO2) in arterial blood and histopathologic changes on 3, 5, 7, 10 post burn day (PBD). The levels of malonyldialdehyde (MDA), myeloperoxidase (MPO), tumor necrosis factor-alpha(TNF-alpha) and interferon-gamma (IFN-gamma) in lung tissue were measured at the same time points., Results: The PaO2 level in A group on 3 PBD (12.58 +/- 0.41 kPa) was significantly higher than that in B group (8.86 +/- 0.23 kPa, P < 0.01). Compared with those in B group, the levels of MDA and MPO were significantly decreased in A group at each time point (P < 0.05 or 0.01), the levels of TNF-alpha on 3, 5, 7 PBD (P < 0.05 or 0.01) and IFN-gamma on 5, 7, 14 PBD (P < 0.01) were also decreased in A group. Swollen lung mesenchyme was alleviated, infiltration of inflammatory cell was lessened in A group., Conclusion: Lytic cocktail combined with immediate fluid resuscitation can inhibit stess response, downregulate the expression of inflammatory factor, ameliorate lung function in severe burn rat at early stage.

Objective: To analyses the clinical application of thoracodorsal artery perforator flaps (TAP)., Methods: We used free or pedicled TAP flaps in 7 patients from Aug 2006 to April 2007, The age ranged from 7 to 42 years old, the perforator arteries was detected and labeled with a hand held Doppler flowmeter, the size of flaps ranged from 6 cm x 9 cm - 12 cm x 16 cm, the flaps designed with perforator artery included, all the flaps are based on the first perforator artery., Results: All the flaps survived well, no complication occurred with lowest donor site morbidity., Conclusions: The thoracodorsal artery flap with latissimus dorsal muscle saved is a thin and reliable flaps with robust of blood supply, the flap can reduce significantly donor site morbidity and is a good choice for reconstructive surgery.

Objective: To analyze the epidemiology of methicillin resistant Staphylococcus aureus (MRSA) in molecular level in burn centre of Shanghai Ruijin hospital., Methods: The vicissitude of Staphylococcus aureus in the burn centre from 2003 to 2005 was analyzed with software WHONET5. Multiprimer random amplified polymorphic DNA(RAPD) was used to analyze the homology of 17 MRSA strains., Results: RAPD analysis (primer ERIC2 and RAPD7) showed that all 17 MRSA strains were identical (Burn-A type)., Conclusion: MRSA with same RAPD type is prevalent in our burn centre for many years, so emphasis should be laid on the anti-infection therapy and its cross infection control. Staphylococcus aureus;

Objective: To isolate and purify high purity 23-hydroxybetulinic acid from the roots of Pulsatilla chinensis., Methods: By acid hydrolysis, silica gel column chromatographies and recrystalization methods, 23-hydroxybetulinic acid was obtained from the roots of P. chinensis., Results: High purity 23-hydroxylbetuline acid was isolated from the roots of P. chinensis, the contents is over 98. 0%., Conclusion: The preparation process is feasible and convenient. High purity 23-hyroxybetulinic acid could be used in the quality control of the materials and medicament of 23-hydroxybetulinic acid.

Objective: To explore the clinical significance of changes in urine microalbumin (UM) and endothelin (ET) in different courses of type 2 diabetes., Methods: A clinical analyses of 30 type 2 diabetic patients with vascular complications (group A) was conducted in comparison with type 2 diabetic patients without vascular complications (group B) and patients with impaired glucose tolerance (IGT, group C). With 30 healthy subjects with family history of type 2 diabetes (group D) and 30 healthy subjects without such family history (group E) as controls, UM and ET were determined in all the subjects for a statistical analysis., Results: Significant differences in UM content was noted between group A and the other 4 groups (P<0.05), while the content did not differ significantly between the latter 4 groups (P>0.05). ET content was significantly higher in group A than in the other 4 groups (P<0.01), and was the lowest in group E (P<0.01)., Conclusions: Type 2 diabetic patients sustain extensively impaired endothelium function, which is exacerbated with the progression of the disease courses. Synchronized changes between vascular complications and impaired endothelium function indicates that vascular endothelial injury relates to vascular complications and the progression of diabetes.

Objective: To observe the changes in urine albumin (UALB), von Willebrand factor (vWF) and platelet-activating factor (PAF) in different courses of type 2 diabetes., Methods: Levels of UALB, vWF and PAF were determined in 30 type 2 diabetic nephropathy patients(group A), type 2 diabetic patients without DNP(group B, n=30), patients with impaired glucose tolerance (group C, n=30), the first-degree relatives of type 2 diabetic patients with normal glucose tolerance(group D, n=30) and 30 normal glucose tolerance subjects without family history of type 2 diabetes(group E)., Results: UALB and PAF contents were significantly higher in group A than in the other groups (P<0.01), while between the latter 4 groups, the contents showed no significant differences (P>0.05). Serum vWF level was significantly higher in group A than those in the other groups (P<0.05)., Conclusions: Renal dysfunction and platelet activation are present in type 2 diabetes with microvascular complications, and the synchronized changes between renal dysfunction and platelet activation indicate the involvement of elevated PAF in vascular injury.

Objective: To investigate the influence of inhibition of stress on the survival rate, organ dysfunction and (Th)1/Th2 cytokine profiles of the rats with invasive infection in the wound at early postburn stage., Methods: Sprague-Dawley rats inflicted with 30% TBSA full thickness burn were randomly divided into A (n = 36, with immediate resuscitation), B (n = 36, with immediate resuscitation and lytic cocktail administration). After subeschar injection of 0.1 ml Pseudomonas aeruginosa (10(8) CFU/ml) on 3rd postburn day, the subeschar bacterial quantitative analysis, the survival rate at 96 hours after bacteria injection, the parameters of organ dysfunction and the mRNA expression of IL-2, IL-4, IL-10 and IFN-gamma were determined by corresponding methods., Results: The quantity of subeschar bacteria was larger than 1 x 10(5)/gram in both groups. The survival rate in B group (66.7 +/- 2.6)% was obviously higher than that in A group (33.3 +/- 1.7)%, (P < 0.01). Inflammatory infiltration and pathological changes in the internal organs in B group were alleviated obviously compared with A group. The expression of IL-2 mRNA in B group was significantly lower than that in A group before bacterial inoculation, but increased at 48 and 96 hours after bacterial inoculation, while it was lowered in A group at the same time points (P < 0.05). The expression of IFN-gamma mRNA in A group was significantly lower than that in B group (P < 0.01), while that of IL-4 and IL-10 mRNA in A group was evidently higher than that in B group (P < 0.05 approximately 0.01)., Conclusion: Inhibition of the stress response during early postburn stage could be beneficial to the prevention of the bacterial invasion due to the changes in Th1/Th2 ratio.

Objective: To investigate the effect of a tight control of blood glucose by intensive insulin therapy on human sepsis, and to explore the potential mechanism of the intensive insulin therapy., Methods: Eligible patients were randomized by a blinded pharmacist to receive tight control of blood glucose by intensive insulin therapy (maintenance of blood glucose at a level between 4.4 and 6.1 mmol/L) or to receive conventional treatment (maintenance of glucose at a level between 10.0 and 11.1 mmol/L). The expression of HLA-DR on peripheral monocytes was measured in 54 patients by flow cytometry on 24 h, 3 d, 5 d, 7 d, 10 d and 14 d of intensive care in parallel with serum c-reactive protein (CRP), severity of the disease (APACHE II score, SOFA score) and clinical data collection., Results: Patients receiving intensive insulin therapy were less likely to require prolonged mechanical ventilation. Tight control of blood glucose significantly reduced the number of days during which leukopenia or leukocytosis and the days with hypo- or hyperthermia (P < 0.05). Hypoglycemia occurred in 3 patients (10.7%) in the tight control of blood glucose group. There were no instance of hemodynamic deterioration or convulsions. Compared with the conventional treatment, tight control of blood glucose also increased the HLA-DR expression of peripheral monocytes, and there were significantly difference on 3 d, 5 d and 7 d (P < 0.05). Whereas it suppressed the elevated serum CRP concentrations, there was significantly difference on 7 d (P < 0.05)., Conclusions: Tight control of blood glucose by intensive insulin therapy expedited healing of human sepsis, and increased the HLA-DR expression of peripheral and suppressed the elevated serum CRP. So, it is necessary to use insulin to strict control the glucose levels in human sepsis.

Objective: To study the impact factors and clinical significance of the acute lung injury (ALI) complicating acute pancreatitis., Methods: Two hundred and fifty patients with acute pancreatitis were retrospectively analyzed to study the impact of the clinical types, different stages of the disease, systemic inflammatory response syndrome (SIRS) and its duration on the incidence of ALI. Also, the relationship between ALI and severity of the disease, as shown by acute physiology and chronic health evaluation II (APACHE II) score, the incidence of acute respiratory distress syndrome (ARDS) and multiple organ dysfunction syndromes (MODS), and prognosis was analyzed in patients with acute pancreatitis., Results: Our data showed that the clinical types and different stages of acute pancreatitis were significantly related to the incidence of ALI (P<0.01). The incidence of ALI was significantly higher in patients with SIRS compared with those no SIRS (P<0.01), and the longer the duration of SIRS, the higher was the incidence of ALI. In patients with ALI, APACHE II score and incidence of ARDS and MODS (P<0.01) were significantly higher, and the prognosis was poor (P<0.05)., Conclusion: SIRS is an important factor that has strong influence on incidence of ALI, and the ALI is an important determinant of prognosis and severity of patients with acute pancreatitis.

Objective: To search an ideal carrier of transferred keratinocytes for transplantation., Methods: The transferred keratinocytes were seeded on the surfaces of the artificial dermis and the silicone membrane and cultured in vitro for 2 weeks. The growth of the keratinocytes was observed by microscope and scanning electron microscope., Results: The keratinocytes implanted on the artificial dermis began to rupture and died after 2 to 3 days. While the keratinocytes adhered well on the surface of silicone membrane with pseudopodia formation after 1 week under scanning electron microscope, and the cells kept normal morphological and proliferative properties 2 weeks later., Conclusion: The silicone membrane can be applied as an useful carrier for the keratinocytes transplantation.