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PURPOSE Because infection can thwart burn healing, microorganisms, their susceptibility patterns, and the effect of tangential excision timing on outcomes of burn patients were examined. METHODS A prospective, observational study was conducted that involved 318 patients with deep second-degree burns from a gas explosion treated in Xinxiang, Henan, China between January 2009 and December 2016. Patient demographic data, culture and antimicrobial susceptibility test results, and outcome variables (resuscitation fluid volume, signs of shock, body temperature, heart rate, and time to wound healing) were analyzed. Outcomes were compared among patients who had early ( 7 days) post burn excision. RESULTS Bacterial culture and drug sensitivity data were available for 314 of the 318 persons with burns >10% of total body surface area (TBSA). Of the 486 bacterial isolates, 330 (67.9%) were gram-negative and 156 (32.1%) were gram-positive. The number of isolates and resistance to third-generation cephalosporins increased over time. Patients having early tangential excision had significantly lower heart rate (P

The infilled frame structure is a kind of structural system used widely in the industrial and civil building. Although the infill walls are no-load-bearing components, the walls are also subjected to some earthquake actions. During some domestic and foreign large earthquakes in recent years, the infill wall were destroyed seriously and the frame were destroyed lightly. The damage of the infill wall not only influences the application of the building, but also increases repair costs for restoring the building, seriously, even endangers the life safety. This paper analyzes the influence of the connection method between the infill wall and the frame on the seismic behaviors of the infilled frame structure. Finally, some new technologies to protect the infill wall and the frame from damage under earthquake are introduced.

Many researchers study the seismic performance of shear wall embedded with reinforced concealed bracings, but not take the shape memory alloy bars concealed bracings into account. Quasi-static tests of a low shear wall with reinforced concealed bracings and a low shear wall with SMA bars concealed bracings are performed to study the seismic performance of the shear walls. Bearing capacity, stiffness, ductility, hysteretic energy and residual deformation of two specimens are researched and analyzed. The experimental results indicate that the SMA bars concealed bracings can increase the strength and ductility of the low shear wall considerably.

The shape memory alloys (SMAs) have received increasing interest attributed to their unique superelastic effect and the shape memory effect. The existing models of superelastic SMAs are generally complex for practical use. In this paper, cyclic loading tests of superelastic SMA wires are first performed. Based on the experiments, a simple constitutive model is set up. Simulations testify that the model can approximately describe the hysteretic characteristics of the superelastic SMA and the simulated mechanical parameters agree well with the experimental values.

To intuitive and accurate quantitatively analyze Raman enhancement of surface enhanced Raman scattering substrate structure, three-dimensional composite structure of silver nanoparticles modified vertically aligned carbon nanotube array is produced by magnetron sputtering and thermal annealing process; Relevant experiments using Rhodamine 6G (R6G) solution as the molecular probes are conducted to analyze surface enhanced Raman enhancement factor (EF), combining with confocal Raman microscopy systems. The result of scanning electron microscopy (SEM) shows that a large number of silver nanoparticles are attached onto the tips and sidewalls of the ordered carbon nanotubes array uniformly. EF of the sample which was produced 30 min annealing time and 450 degrees C annealing temperature evaluates to 2.2 x 10(3), and the reasons for the low EF are analyzed: on the one hand, thickness of silver film sputtered on vertically aligned carbon nanotube array is non-uniform, leading to distribution of silver nanoparticles is uneven after annealing, so that the value of sample roughness is too large, EF value is low; on the other hand, the excitation light source is not the advantage wavelength of silver nanoparticles in the experiments.

Tungsten insert gas (TIG) welding on China low activation martensitic (CLAM) steel under identical conditions was performed. Microhardness test, tensile test, Charpy impact test and microstructure measurements were carried out on TIG welded joints after post weld heat-treatment. Hardening at WM and softening in HAZ is detected in the TIG weld joint. Microhardness in WM decreased when the temperature of PWHT increased. The ultimate tensile stress of weld metal is higher than that of HAZ and BM. Absorbed energy increased with PWHT temperature rising, until PWHT was done at 760 °C/30 min, the specimen ductile fractured in local area. The microstructure of the weld metal for every specimen was found to be tempered martensite with a little of delta ferrite. M23C6 particles are the predominant type of carbides. Oxide precipitate phases appeared in WM, which are the primary crack initiation sites and it is critically important minimize their formation.

Graphene is one of the most popular research topics in carbon nanomaterials. Because of its special physical and chemical properties, graphene will have wide applications. As the production and application amount is increasing, graphene will be inevitably released to the environment, resulting in risks of ecological environment and human health. It is of very vital significance for evaluating environmental risks of graphene scientifically and objectively to understand its environmental behavior and fate and explore its effect on the environmental behaviors of pollutants. This paper reviewed the environmental behavior of graphene, such as colloid properties and its stability in the aqueous environment and its transport through porous media. Additionally, the paper reviewed the effect of graphene on the transport and fate of pollutants. The interactions between graphene and heavy metals or organic compounds were especially discussed. Important topics should be explored including sorption mechanisms, interactions between graphene and soil components, influence of graphene on the transport and bioavailability of pollutants in environment, as well as approaches to quantifying graphene. The review might identify potential new ideas for further research in applications of graphene.

In order to make surface-enhanced Raman scattering (SERS) substrates contained more "hot spots" in a three-dimensional (3D) focal volume, and can be adsorbed more probe molecules and metal nanoparticles, to obtain stronger Raman spectral signal, a new structure based on vertically aligned carbon nanotubes (CNTs) coated by Ag nanoparticles for surface Raman enhancement is presented. The vertically aligned CNTs are synthesized by chemical vapor deposition (CVD). A silver film is first deposited on the vertically aligned CNTs by magnetron sputtering. The samples are then annealed at different temperature to cause the different size silver nanoparticles to coat on the surface and sidewalls of vertically aligned CNTs. The result of scanning electron microscopy(SEM) shows that Ag nanoparticles are attached onto the sidewalls and tips of the vertically aligned CNTs, as the annealing temperature is different , pitch size, morphology and space between the silver nanoparticles is vary. Rhodamine 6G is served as the probe analyte. Raman spectrum measurement indicates that: the higher the concentration of R6G, the stronger the Raman intensity, but R6G concentration increase with the enhanced Raman intensity varies nonlinearly; when annealing temperature is 450 °C, the average size of silver nanoparticles is about 100 to 120 nm, while annealing temperature is 400 °C, the average size is about 70 nm, and the Raman intensity of 450 °C is superior to the annealing temperature that of 400 °C and 350 °C.

To investigate the clinical effects of wrist joint fixation in flexion-ulnar position for the treatment of Colles fracture.From January 1998 to June 2008,120 patients with Colles fracture were treated with wrist joint fixation with plaster in flexion-ulnar position. There were 52 males and 68 females with an average age of 57.6 years (ranged, 22 to 90); 41 cases were left, 69 cases were right, and 10 cases were hibateral. All of them were fresh closed fractures. According to fracture displacement to typing, type I of 34 cases, type II of 36 cases, type III of 32 cases, type IV of 18 cases.With dislocated (II-IV type) 86 patients were followed up for 10 months in average. 86 cases with displaced fragments achieved clinical bony union. According to standard of Dienst, 59 cases got excellent results, 12 good, 10 fair, and 5 poor.The wrist fixation with plaster in flexion-ulnar position in treating Colles fracture may maintain good fixation after reduction and obtain better functional recovery.

To investigate the clinical epidemiological features. of blast injury of lungs caused by gas explosion.A retrospective analysis of 132 cases of blast injury of lungs caused by gas explosion injuries in our hospital from 1990 to 2010 were made, including the information of lung injury, associated injuries, treatment and mortality.56 patients were conscious on admission, during 1 ∼ 5 days, 30 patients got cough, hemoptysis and other pulmonary symptoms, 7 patients had hemothorax, 11 cases combined with pneumothorax, 86 cases of patients with burns, 96 cases with pulmonary aspiration compound injury, 41 cases with abdominal organs blast injuries, 76 cases with pulmonary infection, 31 cases with shock, Seven patients died of respiratory failure, two patients died of respiratory failure.Blast injury of lung featured with serious internal injuries, combined with many injuries, The incidence of compound injury was high, and it was difficult to diagnose. Chest X-ray were varied. The mortality was high, and the predominant causes of death were respiratory failure, shock, sepsis. Most patients with blast injury of lung need tracheotomy and mechanical ventilation. Timely tracheotomy, mechanical ventilation were the major prognostic measures.

To characterize the role of Toll-like receptor 4 (TLR4) in silica-induced production of tumor necrosis factor alpha (TNFalpha) from macrophage cell line.The human macrophage cell line THP-1 was incubated with silica suspension. Cell media were collected and TNFalpha levels in the supernatants measured with ELISA. To examine the involvement of TLR4 in silica-induced TNFalpha release, the neutralizing antibody (HTA125) against human TLR4 receptor was employed to pretreat THP-1 cells prior to silica treatment. Moreover, murine macrophages expressing wild type or mutated TLR4 were also treated with silica to verify the effect of TLR4 in silica-induced TNFalpha release.Compared with the control group [(3.18 +/- 0.41) pg/ml], the TNFalpha release in cells exposed to 100 microg/ml silica for 4 h and 8 h [(4.71 +/- 0.84), (6.22 +/- 0.58) pg/ml, respectively] increased 1.48 and 1.96 fold, respectively. Pretreatment of THP-1 cells with 20 microg/ml HTA125 antibody significantly blocked silica-induced TNFalpha release by 27%. Furthermore, the TNFalpha content released from cells expressing mutated TLR4 reduced by 30% in compared with that from the cells expressing wild type TLR4 after silica stimulation.TLR4 mediates silica-induced TNFalpha release from macrophages.

To explore the expression of NF-kappaB and ICAM-1 in the gas explosion wounded lung of rats and the relationship.Digoxin labeled NF-kappaB was used as probe. In situ hybridization was performed to detect the NF-kappaB mRNA. Immunohistochemistry was used to detect the expression of NF-kappaB and ICAM-1.The levels of NF-kappaB mRNA, the expression of NF-kappaB and ICAM-1 in the wounded rats were significantly increased and reached their peak two hours after injury. Pathology of lung tissue showed that some crachea epithelium mucosae were desquamated; congestion, edema of trachea wall and infiltration of neutrophilic granulocytes were found; hemorrhage, edema and infiltration of lots of inflammatory cells were present in alveolus cells. Electron microscope showed that type I, especially type II alveolus epithelia had degeneration and desquamation.The injury of gas explosion can activate NF-kappaB, which has close correlation with the acute injury to lung.

To explore relationship between rat brain tissues hurts of gas explosion and the expression of Protein Kinase C alpha mRNA.Build up rat hurt model of gas explosion. In Situ Hybridization (IDH) technique was used to test Protein Kinase C alpha mRNA. Immunohistochemical Assays (IHA) was used to determine c-fos gene protein.Only a little a mount expression of PKC alpha mRNA and c-fos of the control group was detected. The expression of the cerebral cortex and hippocampus of PKC alpha mRNA 24 h, 48 h and the 48 h increased obviously, and the 48 h reached the peak of expression; (t = 4.12 P0.01). The expression of c-fos protein of the cerebral cortex and hippocampus started to increase obviously at 0.5 h and the 4 h reached the peak, then the strength lowered gradually and the expression level came back normal level on fifth day.The anoxia of brain tissues due to the gas explosion may promote the expression of PKCamRNA, and PKCamRNA could regulate the expression of the gene of c-fos. Both PKCamRNA and the gene of c-fos are involved in harmful processes to the nerve cells.