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The aviation manufacturing industry is a key area for innovation-driven development. In order to adapt to the new requirements for aviation manufacturing talents put forward by the transformation and upgrading of the aviation industry, Nanchang Hangkong University and AVIC Hongdu Group continue to explore and practice the talent training channels urgently needed for tooling design positions. The university and enterprise jointly built an aviation manufacturing talent training model based on “practical ability-oriented and industry-education integration.” The effective method formed from four aspects: the determination of talent training methods, the establishment of professional curriculum system, the innovation of teaching methods and the improvement of university-enterprise collaborative management mechanism. Thus, the win-win cooperation between the university and enterprise has been realized, and valuable experience has been accumulated for exploring a new aviation manufacturing talent training model.

Porous g-C3N4 composed of nanosheets (p-gCN-NS) was synthesized through firstly grinding the hydrochloric acid-treated melamine with ammonium chloride (NH4Cl) and then calcining the mixture at 550° C for 2 h. The photocatalytic properties were determined by degrading Rhodamine B (RhB) and tetracycline (TC) aqueous solution (10 mg/L, 100 mL). Results show that the crystallinity, size and thickness of g-C3N4 in p-gCN-NS reduced dramatically compared with those in g-C3N4 sample synthesized without the addition of NH4Cl (gCN). Specific surface area of p-gCN-NS was 63.65 m2·g−1, which was 6.7 times that of gCN. After photocatalysis for 50 min, the degradation rate of RhB achieved 99.32% by p-gCN-NS (100 mg), whose reaction rate constant (k = 0.09317 min−1) was 10.6 times higher than that of gCN. p-gCN-NS also exhibited excellent photocatalytic activity for degrading colorless tetracycline aqueous solution. The significant improvement of photocatalytic performance can be credited to the reduced sized and thickness of g-C3N4, higher specific surface area and pore structure, as well as the weakened recombination rate of photogenerated electron–hole pairs in p-gCN-NS. This work provides a feasible and facile method for synthesis porous g-C3N4 composed of nanosheets with excellent photocatalytic performance. [ABSTRACT FROM AUTHOR]

In this paper, a topology optimization approach for the design of laminated composite structures under harmonic force excitations is proposed. A novel method is developed to calculate the harmonic response for composite laminates, which consists of two steps: firstly, based on the strain energy approach, the damping matrix model of composite laminates is established with the proportional damping assumption; then, the displacement response is calculated by the mode acceleration method The design objective of topology optimization is to minimize the displacement amplitude at the concerning point with an excitation frequency or a frequency band. An extended polynomial interpolation scheme is introduced to penalize the stiffness, damped stiffness and mass of elements. The analytical sensitivities of the objective and constraint functions to the density variables are derived in detail, and the globally convergent method of moving asymptotes is used to solve the optimization problem. Numerical examples are performed to demonstrate the effectiveness and feasibility of the proposed topology optimization method in improving the dynamic performance of laminated composite structures. The influence rules of excitation frequency and layer sequence on topologic shape are also discussed. [ABSTRACT FROM AUTHOR]

A substantial fraction of transcripts are known as long noncoding RNAs (lncRNAs), and these transcripts play pivotal roles in the development of cancer. However, little information has been published regarding the functions of lncRNAs in oesophageal squamous cell carcinoma (ESCC) and the underlying mechanisms. In our previous studies, we demonstrated that small nucleolar RNA host gene 5 (SNHG5), a known lncRNA, is dysregulated in gastric cancer (GC). In this study, we explored the expression and function of SNHG5 in development of ESCC. SNHG5 was found to be downregulated in human ESCC tissues and cell lines, and this downregulation was associated with cancer progression, clinical outcomes and survival rates of ESCC patients. Furthermore, we also found that overexpression of SNHG5 significantly inhibited the proliferation, migration and invasion of ESCC cells in vivo and in vitro. Notably, we found that metastasis-associated protein 2 (MTA2) was pulled down by SNHG5 in ESCC cells using RNA pulldown assay. We also found that SNHG5 reversed the epithelial–mesenchymal transition by interacting with MTA2. In addition, overexpression of SNHG5 downregulated the transcription of MTA2 and caused its ubiquitin-mediated degradation. Thus, overexpression of MTA2 partially abrogated the effect of SNHG5 in ESCC cell lines. Furthermore, we found that MTA2 mRNA expression was significantly elevated in ESCC specimens, and a negative correlation between SNHG5 and MTA2 expression was detected. Overall, this study demonstrated, for the first time, that SNHG5-regulated MTA2 functions as an important player in the progression of ESCC and provide a new potential therapeutic strategy for ESCC. [ABSTRACT FROM AUTHOR]

Kaolinite/TiO2 composites were prepared by using sol-gel method and raw kaolin, pretreated kaolinite and tetrabutyl titanate as the main raw materials. X-ray diffractometer, field-emission scanning electron microscope and infrared spectrometer analysis were carried out to characterize the phase composition and microstructure of the samples. The photocatalytic performance of the kaolinite/TiO2 composites were evaluated by degrading the methylene blue (MB) and phenol aqueous solution, respectively. The results show that intercalation and exfoliation reduced the size and thickness of kaolinite particles. Acid treatment improved the distribution and the loading quantity of TiO2 grains. When the kaolinite/TiO2 composites were calcined at 500 °C, the tetragonal structure of anatase particles of 30-100 nm in size were obtained, but the exfoliated kaolinite crystals were damaged. The degradation rate of MB increased gradually with the extension of photocatalytic reaction time and the enhancement of photocatalyst dosage. The adsorption performance of acid-treated kaolinite/TiO2 composite (AKT) was nearly the same as that of raw kaolin/TiO2 composite (RKT), but that of the exfoliated kaolinite/TiO2 composite (EKT) was the most excellent. The photocatalytic performance of AKT and EKT were better than that of RKT, and AKT exhibited the optimum property. Under a certain photocatalyst dosage and photocatalysis time, the absorption rate and the degradation rate decreased gradually with the enhancement of initial concentration of MB. Similar result was also acquired for the degradation of phenol. Both the acid treating and the exfoliating to kaolinite enhanced the photocatalytic performance of the kaolinite/TiO2 composite photocatalysts, but acid treatment may be more helpful to the preparation of high performance kaolinite/TiO2 composite photocatalyst. Natural kaolinite particles were pretreated by acid treating or intercalating-exfoliating.Kaolinite/TiO2 composites were prepared by sol-gel method.Pretreatment of kaolinite improved the photocatalytic performance of kaolinite/TiO2 composite. [ABSTRACT FROM AUTHOR]

Sufu is a pleasant-tasting, traditional Chinese fermented soybean food that is rich in nutrients. The manufacture of sufu includes four steps: preparation of tofu, preparation of pehtze, salting of pehtze and ripening of salted pehtze in a dressing mixture. Based on electrophoresis and 1 H-NMR methods, the changes in protease and chemical compounds in the exterior and interior of sufu were investigated during fermentation. The results indicated that proteases with various molecular masses (162.6, 124.6, 104.3, 66.9, and 44.9 kDa) existed in both the exterior and interior of pehtze, salted pehtze, and ripened sufu, which proved that proteolytic reactions in the exterior and interior of sufu were occurring simultaneously. Furthermore, ethanol, ethylene glycol, glucose, isopropanol, and mannitol were the major carbonic compounds present in sufu, and amino acids were the predominant nitrogen compounds present in sufu. Correlation analysis revealed important links between protease activity and chemical compounds, e.g., succinate, histamine, and trimethylamine, were significantly positively correlated with protease activity in sufu. Through these results, the effect of protease on chemical compounds in sufu was identified, which can be useful for the improvement of enzymatically ripened sufu. [ABSTRACT FROM AUTHOR]

Objective: To investigate the clinical effect of endonasal endoscopic dacryocystorhinostomy（EES-DCR） combined with lacrimal duct drainage tube implantation in treating the patients with lacrimal duct obstruction. Methods: 32 patients （37 eyes） with lacrimal duct obstruction were included into this study, including 1 patient （2 eyes） of functional nasal lacrimal duct obstruction,2 patients （2 eyes） of recurrence after EES-DCR,17 patients （19 eyes） of nasal lacrimal duct obstruction,6 patients （8 eyes） of small lacrimal sac, and 6 patients （6 eyes） of lacrimal duct obstruction. Intraoperative EES-DCR was performed, and lacrimal drainage tubes were implanted from the upper and lower lacrimal points. Septoplasty was performed in 3 patients with nasal septum deviation, and endoscopic sinus surgery was performed in 1 patient with chronic sinusitis.After operation, nasal hormone spraying was performed. During follow-up, the operation effect was evaluated according to the degree of symptom improvement, the patency of lacrimal passage irrigation and the opening state of dacryocystorhinostomy under nasal endoscope. Results: After 3-30 months of follow-up, 29 cases（34 eyes） were cured, 2 cases（2 eyes） were improved, and 1 case（1 eye） was ineffective. The total effective rate was 97.3%（36/37）. No intraorbital, intracranial or nasal complications occurred in all patients. Conclusion: EES-DCR combined with lacrimal duct drainage tube implantation is safe and effective in treating lacrimal duct obstruction. Implantation of lacrimal duct drainage tube can effectively avoid stoma blockage, prevent the adhesion of lacrimal duct, and significantly improve the success rate of surgery., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright© by the Editorial Department of Journal of Clinical Otorhinolaryngology Head and Neck Surgery.)

Laryngeal cancer has become the focus of research because of its high incidence rate and mortality rate. However, the research on miR-194-5p in laryngeal cancer is quite rare. The purpose of this study is to explore the effect of miR-194-5p on the proliferation and invasion of laryngeal cancer cells in order to find an effective way to treat laryngeal cancer. The results showed that miR-194-5p could activate the mTOR signaling pathway by regulating the expression of Smurf1, which had an effect on laryngeal cancer cells. The results showed that the absorbance of the miR-194-5p group was 0.38 lower than that of the NC group, which indicated that up-regulation of mir-194-5p could weaken the proliferation of laryngeal cancer cells. In addition, the average number of laryngeal cancer cells in NC and the miR-194-5p groups was 125.2 and 53.8, respectively, which indicated that miR-194-5p could reduce the number of laryngeal cancer cells passing through the basement membrane and their invasion ability.

Modified g-C 3 N 4 samples (g-X, where X corresponds to the number of hours of acid treatment of the melamine) with outstanding photocatalytic performance were prepared by using hydrochloric acid-treated melamine as a precursor and calcining at 550 °C for 2 h. An x-ray diffractometer, field-emission scanning electron microscope, infrared spectrometer, N 2 adsorption-desorption test, x-ray photoelectron spectroscopy, and ultraviolet-visible diffuse-reflectance spectroscopy analysis were carried out to characterize the phase composition, microstructure, chemical structure, specific surface area (SSA), chemical states, elemental composition and optical properties of the samples, respectively. The photocatalytic performance of the samples was evaluated by degrading the Rhodamine B (RhB) aqueous solution. The results showed that the crystal structure and vibration bands of melamine changed due to the reaction with hydrochloric acid. The crystallinity and grain size of g-C 3 N 4 in g-X (X = 1, 2, 4, 6, 8, 10) reduced, and the SSA values of g-X increased compared to that of the g-0 sample, which was synthesized from pristine melamine. The g-X samples exhibited excellent photocatalytic activity towards degradation of RhB compared to g-0. The photocatalytic activity of the g-X samples increased gradually as the acid treatment time of the melamine increased from 1 h to 2 h, and then decreased gradually with the extension of the acid treatment time. The rate constant (k) values of g-X are higher than that of g-0. g-2 presented the highest rate constant (k = 0.052 min -1 ), which was 5.5 times higher than that of g-0. The improved photocatalytic activity of the g-X samples was attributed to the higher SSA value, the appearance of surface defects, the outstanding photo-carrier separation efficiency and stronger light harvesting ability of g-X, with the last two factors being more significant. Acid treatment of melamine is helpful in the preparation of high performance g-C 3 N 4 photocatalyst, and the microstructure and photocatalytic performance of g-C 3 N 4 were affected significantly by the acid treatment time.

Forsythia suspensa root is used in the treatment of fever and jaundice in Traditional Chinese Medicine. In the present study, the anti-tumor activity of the ethanolic extract of Forsythia suspensa root (FSREE) against esophageal carcinoma cells was investigated in vitro and in vivo and its anti-cancer mechanism was examined. The results revealed that FSREE, rather than Forsythia suspensa ethanolic extracts from the leaf (FSLEE) and fruit (FSFEE) exhibited marked anti-tumor activity towards human esophageal cancer cells. FSREE induced cancer cell apoptosis and growth arrest by downregulating B‑cell lymphoma (Bcl)‑2, Bcl‑extra large and myeloid cell leukemia 1, while upregulating Bcl‑2‑associated X protein, Bcl‑2 antagonist of cell death and phorbol‑12‑myristate‑13‑acetate‑induced protein 1. This led to the activation of poly(ADP ribose) polymerase, caspase‑3 and caspase‑9, but not caspase‑8. Furthermore, the anti-cancer activity of FSREE was associated with a decreased level of phosphorylated Janus kinase/signal transducer and activator of transcription 3 and extracellular‑signal‑regulated kinase signaling activity. It was also observed that the levels of cytochrome c were elevated in the cytoplasm, accounting for the loss of mitochondrial membrane potential in the TE‑13 cells upon treatment with FSEER. In addition, FSEER inhibited the growth of esophageal cancer cells in xenograft models and no detectable toxicity was present in the lung or liver tissues. These observations provided further evidence of the anti-tumor effect of FSEER and may be of importance to further examine the potential role of Forsythia suspensa root as a therapeutic agent in esophageal carcinoma therapy.

Objective: To explore the clinical signification of screening 16 target deafness mutations in GJB2, GJB3, SLC26A4, WFS1 and mitochondrial DNA 12S rRNA in 135 children patients with non-syndromic sensorineural hearing loss (NSHL) in Zibo City, Shandong province., Method: Peripheral blood samples of 135 subjects in the study diagnosed as NSHL were collected; Polymerase chain reaction (PCR) and direct sequencing were used to analyze the 16 mutation spots., Result: Sixty-two cases of 135 patients (45.9%, 62/135) were found out to be carries of at least one pathogenic gene mutation. Among them, 24 cases (17.8%, 24/135) had two mutated alleles (homozygote and compound heterozygote), and 38 cases (28.1%, 38/135) were single mutant carriers. Among all the children patients, 30 cases (22. 2%, 30/135) had SLC26A4 mutations, and 19 cases (14.1%, 19/135) had GJB2 mutations. In the study 86 Mutant alleles were detected, and the allele frequency of SLC26A4 c. 766_2A > G and GJB2 c. 235delC was 11.11% (30/270) and 8.5% (23/270) respectively. The allele frequency of SLC26A4 c. 2168A > G and WFS1 c. 2158A > G is 2.6% (7/270)., Conclusion: SLC26A4 mutation is the primary cause of the patients with NSHL in this study, and GJB2 mutation is the secondary. The most common mutant form is c. 766_2A of SLC26A4, and the second is c. 235delC of GJB2. GJB3 and WFS1 mutations were detected, whereas mtDNA mutations were not found out in this study.

Objective: By analysing the video-nystagmography findings of positional tests,to evaluate the therapeutic effect of the patients with horikontal semicircular canal cupulolithiasis (HSC-Cup)., Method: A retrospective study of 36 patients with HSC-Cup. The induced nystagmus in roll tests was recorded by videonystagmography, whose direction, latency, intensity and time characteristics were analysed. All of the 36 patients were treated with lying position avoiding normal side and oral-taken betahistine mesilate tablets. A week later return visits and curative effects evaluation were made., Result: Horizontal apogeotropic nystagmus was induced by turning left or right in HSC-Cup roll tests. The time of latency and duration turning to normal and lesion side were(0. 93 ± 0. 65)s and(1. 01 ± 0. 78)s, (100.58 ± 36. 56)s and (118. 65 ± 143. 71)s, which showed no statistically significant difference (P>0. 05). The duration of nystagmus was more than 60 seconds. The intensity of nystagmus turning to normal and lesion side were(45.58 ± 28.71)°/s and (20.42 ± 16. 64)°/s. The intensity turning to normal side was greater than lesion side obviously. The difference was statistically significant (P<0. 05). Twenty-three patients withright HSC-Cup, and 13 patients with left HSC-Cup were taken in count. They were treated with above methods and return visit a week later. Twenty-eight patients (77. 77%) were cured, 36 patients (100. 00%) were improved. There were 4 patients recurrence during the follow-up., Conclusion: The direction and duration time of induced nystagmus are available to diagnose the HSC-Cup. The lesion side may determined according to the intensity of induced nystagmus. Lying position avoiding normal side and oral-taken betahistine mesilate tablets is an effective treatment methods for HSC-Cup.

Objective: To investigate the screening value and the reliability of the monothermal caloric tests (MCT) in evaluating vestibular function., Method: One thousand and four hundred and six vertigo patients were divided into two groups. Seven hundred and five cases were stimulated by different temperature air from cold to warm. The caloric test sequence of other 701 cases was opposite. The first stimulated cold or warm air test was regarded as monothermal cold caloric test (MCCT) or monothermal warm caloric test (MWCT). The unilateral weakness (UW) and directional preponderance (DP) of the bithermal caloric tests (BCT) and the UW of the MCT were calculated. By defining the BCT results as the standard, the sensitivity, specificity, Youden's index and kappa were calculated., Result: Four hundred and twenty-eight showed abnormal BCT and MCCT. One hundred and forty-five showed normal BCT and MCCT. 85, 47 showed isolated abnormal BCT and abnormal MCCT respectively. The sensitivity of the MCCT was 83.4%, specificity was 75.5%, Youden's index was 0.589 and kappa was 0.555 (P<0.01). Four hundred and twenty-nine showed abnormal BCT and MWCT, 130 showed normal BCT and MWCT. 82, 60 showed isolated abnormal BCT and abnormal MWCT respectively. The sensitivity of the MWCT was 84.0%, specificity was 68.4%, Youden's index was 0.524 and kappa was 0.505 ( P<0.01). The sensitivity of the MCCT and MWCT were 86.9% and 86.9% respectively when cases accompanied by spontaneous nystagmus (SN) were excluded. The sensitivity of the MCCT and MWCT were 89.3% and 88.1% respectively when cases with abnormal DP were excluded., Conclusion: The high false-positive and false-negative rate of the MCT limit the usefulness as a screening test due to the influence of DP and SN.

The polarographic behavior of the reaction product of formaldehyde and phenyldrazine hydrochloride on the drop mercury electrode was investigated in a medium of 0.01 mol/L H3PO4 and sensitive second order polarographic reduction wave was obtained at -0.76 V (vs. SCE). The optimum conditions and disturbance of other co-existing substances were also studied, and were compared with those of national standard method. In the study, the detectable range, detection limit, recovery rate, relative standard deviation(RSD) of the improved method were 0.005-0.25 mg/L, 0.005 mg/L, 92.3%-104.6%, 1.1%-3.0% respectively, revealing the accordance with the national standard method.