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A very simple synthesis method of AlN-SiC solid solution powder, i.e. self-combustion of Al, Si3N4 and C mixture in the air only with assistance of high-energy mechanical milling, was proposed in the present work. The effect of compositions on the combustion behavior and the product was studied and the results showed that the amount of Al in the starting powder was the key factor affecting the combustion behavior, the phase assemblages and the morphology of products.

Copolymer emulsions containing fluorine were prepared by emulsion polymerization with MMA, BA and G06B using SDBS as emulsifier. The copolymer was characterized by FTIR and DSC. The size and distribution of the latex particle in emulsion were obtained by particle size analyzer. The stability of emulsion was observed and the solvent resistance of latex films was investigated. Surface properties of the copolymer film were investigated by contact angle measurement. The results showed that adding fluorine group to copolymer could increase hydrophobic property of the latex film and decrease the surface free energy of copolymer film. Glass fiber will have excellent properties when combining with the copolymer emulsion.

Europium-doped nanocrystalline ZrO2: Eu3+ powders with different doped concentrations were prepared by emulsion processing method, with different doped concentration and calcination temperature on the material grain size, structure, size and luminescent properties. The results show that: Eu3+ has a stabilizing effect on tetragonal phase of ZrO2. Emission spectra indicates that the main emission peak in the 593m and 608m, “Blue Shift “will occur in 5D0 → 7F2 transition of the emission spectra of sample with the sintering temperature at 1000°C. Samples with the sintering temperature soaring, spectral emission intensity also increases.

The cyclic oxidation behavior of Ti2AlN and Ti2AlN/TiN composites were investigated at 800°C, 900°C and 1000°C. The phase composition, thickness of oxidation layer and element content of samples were investigated by XRD and SEM coupled with EDS. The cyclic oxidation behaviors generally follow a parabolic rate law, with good thermal shock resistance. The antioxidation property of Ti2AlN/TiN composite is better than Ti2AlN. Oxidation process of single-phase Ti2AlN is composed by the outward diffusion of Al3+ and Ti4+, and inward diffusion of oxygen. Oxidation process of Ti2AlN/TiN composite consists of two parts: firstly, the oxidation of TiN, the oxidation temperature is 500°C; the second step is the oxidation of Ti2AlN, carried out in the 800-1000 °C.

The isothermal oxidation behaviors at 800-1000°C for 20h in air of bulk Ti2AlN and Ti2AlN/TiN were investigated by TG, XRD and SEM coupled with EDS. The oxidation behaviors generally follow the parabolic law. The activation energies of Ti2AlN and Ti2AlN/TiN composite are 614.93 KJ∙mol-1and 541.35 KJ∙mol-1respectively. The antioxidation property of Ti2AlN/TiN composite is better than Ti2AlN. Oxidation process of single-phase Ti2AlN is composed by the outward diffusion of Al3+and Ti4+, and inward diffusion of oxygen. Oxidation process of Ti2AlN/TiN composite consists of two parts: firstly, the oxidation of TiN, the oxidation temperature is 500 °C; the second step is the oxidation of Ti2AlN, carried out mainly in the 800-1000 °C.

The segregation of land-use intensity signifies an important change in land use in lac insect agroecosystem of Southwestern China. Farming conversions have led to a highly diversified landscape, with a mosaic made up of patches of land with different succession, from cultivated lands to closed forest. Our aim here is to characterize ant assemblages within this mosaic and identify key ant community metrics and species that can be used for bioindication. The habitats supported different level of ant species richness and abundance. For ants captured by pitfall trapping, the mean plot species richness in lac plantation was significantly higher than that in dry land (deforestation land-use). For ants captured by sweep netting and foliage shaking, there was significant difference among lac plantation, dry land and secondary forest occurring from afforestation of lac plantations, with lac plantation having greatest species richness. Ant species composition was different among the three land-use habitats. Seven of the fifteen most common species had statistically different abundances or occurrence within the three land-uses. Thirteen species had statistically significant different distributions among land-use habitats (among them three species were captured by sweep netting and foliage shaking). Ten species had statistically significant habitat associations determined by IndVal analysis. Among these ten species, five ant species were associated with secondary forest, two with lac plantation, and three with dry land. Lac plantation integrated with lac-production and farming is clearly an important land-use protecting ant diversity, and thus having great conservation potential. The use of ants as bio-indicators is a promising method for determining ecological responses to human land use in China.

We describe grasshopper (Acridoidea) diversity in differentially used lac ecosystems located in Lüchun County, Yunnan Province, China. Grasshoppers were sampled by sweep netting in 13 plots, representing four land utilization ecosystems: 1) secondary natural lac forest occurred from afforestation of lac plantations (3 plots); 2) lac plantations (3 plots); 3) crop lands (3 plots); and 4) agricultural paddy fields (4 plots). A one-year sampling effort yielded 1,385 acridids, representing 31 species in five families. Grasshopper abundance and richness were correlated to plant resources, which, in turn, correlated to land utilization. Local grasshopper assemblages were reasonable indicators of habitat differences, although they were not consistent with land utilization intensity. In term of grasshopper biodiversity conservation and economic development, the lac agroecosystem, which is composed by lac plantations, paddy fields and crop lands, most likely is the better choice for a balanced approach between conservation and development in mountainous areas of southwest China than any of the any of those areas by themselves because this combination of land use maintains the highest number of species and allows human farming activities.

Two series of raw materials were adopted to form TiAl/Ti 2 AlC composites: Ti/Al/TiC and Ti/Al/C. Differential thermal analysis (DTA) of starting powers and X-ray diffraction (XRD) of samples sintered at different temperatures from 600 °C to 1300 °C by hot pressing were utilized to analyze the phase transformation and the mechanism of synthesis. Scanning electron microscopy (SEM) coupled with energy-dispersive spectroscopy (EDS) was utilized to investigate the morphology characteristics of the products. The experimental results showed that Ti reacted with Al to form TiAl intermetallics below 900 °C; and above 900 °C, TiAl reacted with TiC to produce dense TiAl/Ti 2 AlC composites. The products sintered at 1200 °C had fine crystals and dense fibres, and the distribution of Ti 2 AlC particles in TiAl matrix was homogeneous.

Adsorption of hydrogen sulphide (H 2 S) onto activated carbons derived from oil palm shell, an abundant solid waste from palm oil processing mills, by thermal or chemical activation method was investigated in this paper. Dynamic adsorption in a fixed bed configuration showed that the palm-shell activated carbons prepared by chemical activation (KOH or H 2 SO 4 impregnation) performed better than the palm-shell activated carbon by thermal activation and a coconut-shell-based commercial activated carbon. Static equilibrium adsorption studies confirmed this experimental result. An intra-particle Knudsen diffusion model based on a Freundlich isotherm was developed for predicting the amount of H 2 S adsorbed. Desorption tests at the same temperature as adsorption (298 K) and at an elevated temperature (473 K) were carried out to confirm the occurrence of chemisorption and oxidation of H 2 S on the activated carbon. Surface chemistries of the palm-shell activated carbons were characterized by Fourier transform infrared spectroscopy and Boehm titration. It was found that uptaking H 2 S onto the palm-shell activated carbons was due to different mechanisms, e.g. physisorption, chemisorption and/or H 2 S oxidation, depending on the activation agent and activation method.

Treadmill Measurement of Maximal Aerobic Capacity in Untrained Students Aged 9-18 Year

To investigate the incidence and severity of pulmonary function impairment in patients with chronic rhinosinusitis with nasal polyps (CRSwNP).In this prospective study, fifty-six patients with bilateral CRSwNP who were scheduled for functional endoscopic sinus surgery during a period from March to June 2010 in the Department of Otolaryngology of Qilu Hospital, were recruited in this study. Routine medical and rhinological examinations such as nasal endoscopy, sinus CT scan, and skin prick tests (SPT) for common inhalant and food allergens, and cytological examination of the paraffin-embedded NP tissues were performed together with a full assessment of the pulmonary functions.Based on the pulmonary function tests, the rate of patients showing bronchial hyperresponsiveness (BHR), asthma, and abnormal pulmonery functions were 37.5%, 44.6%, and 53.6%. In patients who did not have a history of lower airway symptoms, the rate of abnormal pulmonary functions was 50.0%, the rate of BHR was 43.2%. There was an increased rate of BHR, asthma and abnormal pulmonary functions in patients with a higher polyp grading score or Lund Mackay CT scan score (polyp grading score: χ(2) were 8.077, 3.989 and 7.445, P0.01 or0.05. CT scan score: χ(2) were 3.863, 5.380 and 4.309; 4.293, 4.293 and 4.572; 10.572, 13.504 and 13.295, P0.01 or0.05). The rate of BHR and asthma in patients with positive SPT were higher (P0.05). In patients with eosinophils hyperplasia in nasal polyps, the rate of BHR, asthma and abnormal pulmonary functions were higher (χ(2) were 4.065, 5.217 and 3.376, P0.05 or P0.01).There is a high risk of developing lower airway diseases in patients with CRSwNP.

To investigate the effects of sIL-5Rα and sIL-13Rα2 on VCAM-1 and IFN-γ in allergic rhinitis rats.A total of 50 Wistar rats were randomly divided into 5 groups: the normal group (group A), the allergic rhinitis model group (group B), the sIL-5Rα treatment group (group C), the sIL-13Rα2 treatment group (group D), the combination of sIL-5Rα and sIL-13Rα2 treatment group (group E or the combined treatment group). Rats in the latter 4 groups were sensitized with ovalbumin (OVA) and Al(OH)(3), and challenged with OVA to establish allergic rhinitis models, while rats in the normal group were treated with saline. Rats in the sIL-5Rα treatment group, the sIL-13Rα2 treatment group and the combined treatment group were absorbed on day 31 to day 38 once daily once nasal cavity with sIL-5Rα(100 µg), sIL-13Rα2 (100 µg) and the combination of sIL-5Rα (100 µg) and sIL-13Rα2 (100 µg) 30 min before challenged, while rats in the allergic rhinitis model group received PBS(50 µl). Then the levels of VCAM-1 and IFN-γ in serum and nasal lavage fluid (NLF) were measured by ELISA.Compared with the normal group, the levels of VCAM-1 in the allergic rhinitis model group were higher, while IFN-γ were lower (all P0.01). Compared with the allergic rhinitis model group, the sIL-5Rα treatment group, the sIL-13Rα2 treatment group and the combined treatment group could effectively reduced serum and NLF VCAM-1 level [group E: (283.5 ± 5.7) µg/L, (101.8 ± 4.8) µg/L; group C: (311.5 ± 12.6) µg/L, (133.9 ± 5.8) µg/L; group D: (304.7 ± 6.6) µg/L, (128.5 ± 7.7) µg/L], and increased IFN-γ level [group E: (874.7 ± 9.6) pg/ml, (349.2 ± 12.1) pg/ml; group C: (600.2 ± 16.1) pg/ml, (195.5 ± 16.1) pg/ml; group D: (577.9 ± 9.6) pg/ml, (196.7 ± 9.9) pg/ml ]; compared with single treatment, the combined treatment group also had significant differences(P0.01).Combined treatment with sIL-5Rα and sIL-13Rα2 to treat the allergic rhinitis rats can significantly reduce VCAM-1 levels in serum and NLF, and increase IFN-γ levels, thus, to achieve the purpose of mitigation and treatment of allergic rhinitis.

To explore the feasibility of laryngeal function preservation in surgical treatment of hypopharyngeal carcinoma with restrained vocal cord motility.Twenty-six cases of hypopharyngeal carcinoma treated with conservative hypopharyngectomy were retrospectively analyzed. Partial resection of pyriform sinus and partial laryngectomy were performed. Suturing the remaining hypopharyngeal mucosa was used to cove the wound of hypopharynx in 5 cases, epiglottis complex flap in 21 cases. All patients received postoperative radiotherapy.The overall 3- and 5-year survival rates were 61.4% and 50.8% respectively. 76.9% (20/26) patients have laryngeal functions (voice, respiration and deglutition) completely restored and 23.1% (6/26) partially restored (voice and deglutition).To improve the quality of life of the cases, the preservative surgery is feasible for the selected hypopharyngeal carcinoma cases with restrained vocal cord motility.

To investigate the effects of intranasal interferon gamma (IFN-γ) on nasal mucosa remodeling and expression of transforming growth factor-β1 (TGF-β1), Smad2, Smad3, Smad7 in allergic rhinitis (AR) rat model.Ovalbumin (OVA) and aluminum hydroxide were used to construct the AR model. Thirty AR rats were randomly divided into positive control group (group B, n = 10), IFN-γ treatment group (group C, n = 10) and negative control group (normal rats, n = 10). After the AR models were built, 50 µl PBS, 1 µg IFN-γ was dropped into the nasal cavity of each rat in group B and group C, from the fouth week to tenth week, twice a week. The nasal mucosa was collected on day 71 in order to observe the pathologic changes, and the expression of TGF-β1, TGF-β1 mRNA, Smad2 mRNA, Smad3 mRNA and Smad7 mRNA by immunohistochemistry and reverse transcriptase-polymerase chain reaction.Decreases of TGF-β1, Smad2 and Smad3 mRNA were seen in nasal tissue of group C (0.59 ± 0.04, 0.39 ± 0.08, 0.46 ± 0.15) as compared with group B (0.82 ± 0.12, 0.70 ± 0.18, 0.95 ± 0.26), the differences were significant (q value were 3.15, 4.47, 3.03, all P0.05). The levels of Smad7 mRNA expression increased significantly (q = 2.98, P0.05) in group C (0.31 ± 0.05) as compared with group B (0.25 ± 0.06). Immunohistochemistry showed significant decrease of TGF-β1 expression in the nasal tissue of group C much lesser than that in group B.Intranasal IFN-γ could decrease the expression of TGF-β1, TGF-β1 mRNA, Smad2 mRNA, Smad3 mRNA, increase the expression of Smad7 mRNA in AR rats model and inhibit the nasal mucosa remodeling.

To study the voice function rehabilitation by mucosa tube performed in operation of late laryngocarcinoma and to improve the survival quality of patients with late laryngocarcinoma.Forty-six patients were treated between Oct. 1991 and May 2006, including 41 males and 5 females. The average age of the patients was 54. Seventeen cases were glottic carcinomas (T3N0M0 12, T3N1M0 5), 27 cases were supraglottic carcinomas (T3N1M0 16, T4N1M0 5, T3N0M0 6), 2 cases were pyriform sinus cancer (T4N1M0 2). For those patients with late laryngocarcinoma, who had lost the chance of partial laryngectomy, mucosa tube shaping during the operation could realize voice functional rehabilitation. Only the survive arytenoids of healthy side was preserved, in order to rehabilitate voice, a mucosa tube was sutured using healthy survive arytenoids and a mucosa strip was connected to the trachea and the mucosa of hypopharynx. Survival analysis was performed by using Kaplan-Meier method.Forty-one out of 46 patients obtained almost normal voice and swallow function. The 5-years survival was 76%.The operation of voice function rehabilitation by mucosa tube performed can get good voice and swallow function to patients with late laryngo carcinoma.

The grasshopper communities in the paddy field, dry land, natural forest, and plantation forest of lac plantation-farmland ecosystem in Lvchun County, Yunnan were investigated by sweep netting. A total of 1426 grasshoppers belonging to 33 species, 22 genena, and 5 families were captured. In the paddy field, dry land, natural forest, and plantation forest of the ecosystem, the species richness S were 16.333, 13.000, 11.000, and 12.000, Margalef index was 2.873, 2.266, 2.335, and 2. 137, Shannon-Wiener index was 2.034, 1.976, 1.982, and 1.488, Simpson index was 0.196, 0.189, 0.174, and 0.323, and Pielou index was 0.728, 0.787, 0.829, 0.599, respectively. This ecosystem had a lower diversity of grasshopper communities, and different land use habitats in the ecosystem had different species component and diversity. In paddy field, grasshopper had a higher diversity than in dry land, but its evenness and stability were moderate; in natural forest, the diversity was high and the stability was strong; while in plantation forest, the diversity was low and the stability was weak. There existed species exchange in different land use habitats in the ecosystem.

To investigate the effects and mechanism of intranasal interferon gamma (IFN-gamma) in the treatment of allergic rhinitis.Ovalbumin (OVA) absorbed to aluminum hydroxide was used to construct the allergic rhinitis model (group C), and the normal control group (group A), the allergic rhinitis model group (group B) and beclomethasone dipropionate group (group D) consisted of 8 rats for each. PBS 50 microl was absorbed to group B, IFN-gamma 1 microg was absorbed to group C and beclomethasone dipropionate 3.5 microg was absorbed to group D on day 31 to day 38 once daily once nasal cavity. The nasal lavage fluid was collected on day 39, and the cellular constituents, levels of interleukin-4 (IL-4), interleukin-5 (IL-5) and IgE were determined, together with the pathologic changes and expression of GATA-3 were observed.Decrease of eosinophils [(0.005 +/- 0.003) x 10(4)/ml, x +/- s] was seen in nasal lavage fluid of group C as comparing with group B [(0.225 +/- 0.060) x 10(4)/ml, (P0.01)], and the levels of IL-4 (7.8 +/- 3.5) pg/ml and IL-5 (12.5 +/- 4.3) pg/ml decreased significantly in comparing with group B (P0.01). The serum levels of total IgE (38.5 +/- 9.6) microg/ml and ovalbumin-specific IgE (19.8 +/- 5.4) IU/ml decreased significantly in comparing with those of group B (P0.01). In group B, mucosal congestion and edema thickening with inflammatory cells infiltration mainly of eosinophils; in group C, the above mentioned changes were much more ameliorated. Immunohistochemistry showed significant increase of GATA-3 expression in the nasal tissue of group B but much lesser than that in group C.IFN-gamma can inhibit the composition of IL-4 and IL-5, and inhibit the airway inflammation with eosinophilic infiltration and the serum levels of total IgE and ovalbumin specific IgE, probably through the mechanism of restraining the Th2 reaction by blockade of GATA-3 expression in the nasal tissue.