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In order to solve the problem of concrete shaft support in deep topsoil layer, ANSYS finite element software was used to compare and analyze the deformation and stress of hybrid fiber high-strength concrete shaft and ordinary high-strength concrete shaft when the thickness of topsoil layer varied from 200 m to 600 m. The calculation results show that: the strain of mixed fiber concrete shaft is greater than that of ordinary concrete shaft under the same stress, and the fiber can improve the brittleness of shaft; the maximum circumferential stress on shaft increases with the increase of topsoil layer thickness, and increases gradually from outside to inside along the shaft radial direction, and the circumferential strain is always compressive strain and the inner surface is greater than the outer surface. As the burial depth increases, the deformation of shaft changes from mainly axial deformation to mainly radial deformation; finally, the regression equation of the relationship between stress-strain and thickness of topsoil layer is given, which can guide the engineering practice.

In the Cyber-Physical system(CPS), equipment generates a large amount of communication information and equipment data during the operation of the system, which are at risk of being modified and stolen. Block chain technology with distributed storage as the core is conducive to ensuring the data security of CPS system, but the existing consensus algorithms have the problem that data recording rights are concentrated in a few nodes and are easy to be hijacked by malicious nodes. By introducing node validity, the dynamic change of node behavior can be reflected. The experimental results show that the consensus mechanism based on the validity of nodes makes the distribution of nodes with access to data records more decentralized, better reflects the de-centralization characteristics of the system, and improves the security of data.

According to the normal production conditions, 13 kinds of n-alkanes were added to the core material sheet production process to prepare heated tobacco products, and a GC-MS analysis method suitable for re-alkanes in the core material, filter and mainstream smoke particulate matter of heated tobacco products was established. The transfer behavior of re-alkanes in heated tobacco products was studied by measuring the content, release and mouth-to-mouth release of re-alkanes in heated tobacco products. The results showed that: 1) The particle phase transfer rates of 13 re-alkanes in mainstream smoke were 0~53. 5 %, the filter interception rate was 12. 6% ~ 50. 0%, the smoke support retention rate was 0. 2% ~ 35. 4%, the smoke core residue rate was 6. 4% ~ 29. 3%, and the loss rate was 0. 6% ~ 81. 5%; With the increase of relative molecular mass and boiling point, the transfer rate of particulate matter and the interception rate of filter in mainstream smoke of n-alkane compounds increased first and then decreased, the residual rate of cigarette core increased gradually, and the retention rate of cigarette support increased first and then stabilized. The smoke retention rate and filter rejection rate showed a good positive correlation with the boiling point of the compound within a certain range. 2) With the increase of the number of suction ports, the release amount of re-alkanes increased first and then decreased, but the order of the maximum release amount was inconsistent. The lower the boiling point of the compound, the earlier the order of the maximum release amount. 3) The coefficient of variation of the puff-by-puff release of re-alkanes ranged from 0. 28 to 0. 44. The coefficient of variation of the puff-by-puff release of tridecane ( boiling point 235°C) and tetradecane ( boiling point 254 °C) was small, and the puff-by-puff release stability was good. Based on the evaluation data of the retention rate of re-alkanes in heated tobacco products, the transfer rate of particulate matter in mainstream smoke, and the stability of puff-by-puff release, the boiling point range of additives suitable for heated tobacco products was proposed to be about 250 °C. [ABSTRACT FROM AUTHOR]

In order to study the influence of filter ventilation of heated tobacco products on aerosol released, 1#--5# heated tobacco products samples with 0, 2, 4, 6, and 8 ventilation holes set at cavity section of filter were prepared. With an in-situ aerosol characterization method with microprobe sampling and a thermocouple temperature measurement method, the effects of ventilation on the physical properties and temperature of aerosol were investigated and analyzed. The results showed that filter ventilation changed the particle size distribution of aerosol in heated tobacco products. The particle number concentration and volume concentration of aerosol behind ventilation holes in heated tobacco products decreased with the increase of the number of ventilation holes. The reduction rate of particle volume concentration of aerosol from sample 5# was 57. 4% compared with sample 1#. Ventilation reduced the count median diameter of aerosol. However, the change of count median diameter with the number of ventilation holes was not significant. The temperature of aerosol in front of and behind ventilation holes decreased with the increase of the number of ventilation holes. The aerosol temperature of sample 5# was 23. 0 °C lower than that of sample 1#. The particle volume concentration and temperature of aerosol in front of and behind ventilation holes were higher at the central axis and lower along the radial distance. [ABSTRACT FROM AUTHOR]

To study the influences of puffing parameters on aerosol particle number and size from electrically heated tobacco products (eHTPs), a smoking cycle simulator-differential mobility spectrometer (SCS-DMS) was used for characterizing the particle number concentration and count median diameter (CMD) of the eHTP aerosol under different puffing parameters with the puffing volume of 35, 55, 75 mL, the puffing duration of 2, 3, 4 s, and the puffing interval of 30, 60 s respectively. The results showed that: 1) During single puff under square wave smoking regime, the particle number concentration of the aerosol from eHTP decreased and the count median diameter became smaller in real time with the proceeding of puffing. 2) The increases of puffing volume and puffing interval evidently increased particle number concentration of aerosol. When the puffing volume increased to 75 mL, the CMD of the aerosol was reduced. Puffing interval had no obvious effect on CMD. 3) Puffing durations slightly influenced the particle number concentration and CMD of the aerosol from eHTP. [ABSTRACT FROM AUTHOR]

Normal and slim cigarettes with different filter ventilation and cigarette paper air permeability were rolled. The effects of filter ventilation, cigarette paper ventilation and ventilation distribution on nine phenolic aroma components release from mainstream cigarette smoke were investigated. The results showed the filter ventilation rate, paper ventilation rate negatively correlated to the releases of nine phenolic aroma components in cigarette smoke, and with the increase of ventilation rate, the decrease rate of maltol with caramel flavour and smaller molecular weight was higher, while the decrease rate of eugenol with smoky flavor and larger molecular weight was lower. No matter normal or small cigarettes, the paper and filter ventilation rate have different effects on the decrease of smoke composition, and the paper ventilation rate has greater influence than the filter ventilation rate. The effects of filter ventilation rate, paper ventilation rate and ventilation distribution on the release of nine phenolic aroma components in conventional cigarette smoke were greater than those in slim cigarette smoke. When the total ventilation rate was the same, the release of 9 phenolic aroma components in cigarette smoke with high filter ventilation rate and low paper ventilation rate was higher than that with low filter ventilation rate and high paper ventilation rate. [ABSTRACT FROM AUTHOR]

In order to investigate transfer behavior of six ester flavors in aerosol of heated tobacco products, puff-by-puff release of six ester compounds in the aerosols of heated tobacco products and the content in cut tobacco was measured using GC-MS at the addition levels of 0.01% and 0.05% respectively. The transfer rates of six ester flavors in the aerosols of heated tobacco products were analyzed. The results showed that with the increase of puff number, the puff-by-puff releases of six ester flavors in aerosol of heated tobacco products showed a trend of first increasing and then decreasing. And the maximum of puff-by-puff transfer release was mainly between the third and fifth puff. The puff-by-puff transfer rate of six ester flavors was 0.70%~8.06%, and the total transfer rate of six ester flavors was between 10.50% and 52.98%. There was a good linear positive correlation between the sum of puff-by-puff transfer rate and the puff number. [ABSTRACT FROM AUTHOR]

In order to investigate the effects of key parameters, including the moisture content, propylene glycol (PG)to glycerin (GLY)ratio and nicotine concentration in e-liquids and the output power of e-cigarette devices, on the releases of aldehydes in aerosol, laboratory-prepared e-liquids were filled into a commercial refillable e-cigarette. The aerosols of 50 puffs were collected from the device, and the releases of formaldehyde, acetaldehyde and acrolein in the aerosols were collected and analyzed by HPLC (High Performance Liquid Chromatography)under the parameters of 55 mL puffing volume, 30 s puffing interval and 3 s puffing duration. The results showed that: 1)Acetaldehyde was mainly from the thermal degradation of PG, formaldehyde was mainly from the thermal degradation of GLY, and acrolein was mainly from the dehydration of GLY at higher temperatures. 2) The releases of aldehydes decreased with the increase of the nicotine concentration in the e-liquids, while increased quickly with the output power of the device. 3)The effect of moisture content in the e-liquids on aldehydes releases was minor. [ABSTRACT FROM AUTHOR]

20 kinds of electrically heated cigarettes from 5 brands in the market were collected to characterize and compare the physical properties (number concentration, count median diameter and volume concentration) of total and puff-by-puff released aerosol. The results showed that the particle number concentration of the total aerosol released from the electrically heated cigarette was mainly in the order of 109/cm³, and the particle volume concentration was in the order of 105 μm³/cm³. The particle size distribution profiles of aerosol were unimodal or bimodal, and the count median diameter was mainly in the range of 30~60 nm. There were obvious differences in physical properties of total and puff-by-puff release of the aerosol from different brands of electrically heated cigarettes. The particle number concentration, count median diameter and volume concentration of the aerosol puff-by-puff released from the electrically heated cigarettes showed a certain degree of instability. [ABSTRACT FROM AUTHOR]

To quantify water-soluble sugars in natural tobacco flavors, the analytical method described in YC/T 447-2012 was optimized, and an HPLC-ELSD method with water extraction was developed to determine 10 water-soluble sugars in natural tobacco flavors, namely rhamnose, stevioside, fructose, sorbitol, mannose, galactose, glucose, inositol, sucrose, maltose. The results showed that: 1) The sample solution with water extraction presented better stability compared with the control method with 0.02 mol/L NaOH extraction. 2) The retention time of the analytes was more stable after adding aqueous ammonia into the mobile phase. 3) The stabilities of ELSD peak areas of the ananlytes were improved at a gas flow rate of 2.20 L/min and a drift tube temperature of 80 °C. 4) The LODs of the 10 sugars were in the range of 4.19-12.30 µg/mL and the spiked recoveries ranged from 80.20% to 106.00% with good intra-day (RSD≤4.05%) and inter-day (RSD≤6.25%) precisions. 5) The contents of these sugars in 239 natural tobacco flavors were determined with the developed method, and the top five sugars were glucose, fructose, sucrose, maltose and sorbitol. [ABSTRACT FROM AUTHOR]

The migration of six flavourings to smoke aerosols and their effects on the physical and chemical properties of aerosols under heating condition were studied by using a smoking machine, combined with GC- MS/MS and fast particulate spectrometer. The results showed that; 1) The six flavourings were mainly evaporated by prototype at 350 °C. 2) The release and migration of the six flavourings showed different characteristics under heating and suction conditions. Isoamyl isovalerate and 2,3,5-trimethylpyrazine were transferred to particle phase and gas phase of aerosol, while the other four flavourings were only transferred to particle phase of aerosol. The total migration rates of geraniol and 2-acetylpyrrole to smoke aerosol were 2.8%~8.1%, and the other four flavourings were 17.6%~54.4%.3) Compared with the blank control, after adding 5% L-menthol or 1% and 2% WS-23, the release amount of nicotine, propylene glycol and glycerol from the tobacco materials to the aerosol was reduced by more than 20%, and their interception in the filter section was reduced by more than 10%. 4) When L-menthol was added to 5%, the particle number concentration decreased by 28% and count median diameter (CMD) increased by 8%. [ABSTRACT FROM AUTHOR]

In order to investigate the effect of different ventilation distribution on organic acid release from mainstream smoke of slim cigarette, the slim cigarette samples with different filter ventilation and cigarette paper air permeability were rolled, and the organic acid in mainstream smoke of samples were analyzed by GC-MS, the prediction models of organic acids release based on both filter and paper ventilation rate were established. The results were as follows: 26 kinds of organic acids were detected. With the increase of filter ventilation rate or paper ventilation rate, the decrease rate of organic acids with smaller molecular weight was higher, while that with larger molecular weight was smaller, and the effect of paper ventilation rate on the release of organic acids in cigarette smoke was greater than that of filter ventilation rate. When the total ventilation rate (V) was constant, the release of organic acids in cigarette smoke with high filter ventilation rate and low paper ventilation rate was higher than that with low filter ventilation rate and high paper ventilation rate. The prediction accuracy of the model of organic acid release was high, and the results further proved that the cigarette organic acid release was higher with the combination of high filter ventilation rate and low paper ventilation rate. [ABSTRACT FROM AUTHOR]

In order to investigate the puff-by-puff discipline of flavor components in the mainstream cigarette smoking, a 20-channel rotary disc smoker modified from a patent in laboratory was used to achieve the puff-by-puff smoking of cigarettes. A GC-MS quantitative analysis method for neutral and alkaline flavor components in single-mouthful particulate phase of mainstream cigarette smoke was established. By using the established analytical method, the puff-by-puff delivery discipline of flavor components and the effects of the permeability of cigarette paper and packaging paper were studied. The results showed that: 1) The established analytical method had a good precision and recovery and was suitable for the quantitative analysis of neutral and alkaline aroma substances in single-mouthful gaseous and granular phase of cigarette smoke. 2) The transport capacity of tar and nicotine in the mainstream cigarette smoke steadily increased with the increase in the number of suction mouths, and decreased with the increase in the permeability of cigarette paper and packaging paper. 3) The transmission of neutral and alkaline aroma components increased with the increase in the number of suction mouths, but the transmission of various flavor components was slightly different, and decreased with the increase of the permeability of cigarette paper and packaging paper. 4) The puff-by-puff contents of neutral and alkaline aroma components in gaseous and granular phase of the mainstream smoke per unit tar and nicotine were the lowest in the first puff, and then were in line with the number of suction puffs. [ABSTRACT FROM AUTHOR]

The CHIRALPAK-IC was used, and the mixed solution of V (re-hexane) : V (isopropanol) = 95 : 5 was used as the mobile phase, and diethylamine was used as the mobile phase additive. In normal phase chromatography mode, a chiral column-high performance liquid chromatography-diode array detector (HPLC-DAD ) method was developed for the separation and analysis of nicotine optical isomers in tobacco and tobacco products. The characterization and test results of this method indicated:) The linear relationship between S-( -)-nicotine and R-( +)-nicotine was in the range of 15 ~750 µg/mL and 0. 75 ~30. 00 µg/mL, respectively. The detection limit and limit of quantification were 0.2 mg/g and 0. 05 mg/g, respectively. 2) The precision of intra- and inter-day measurements of nicotine was less than 0. 85% and 4. 00%, respectively; the recovery rates of S-( - ) -nicotine and R-( + ) -nicotine were 94. 93% ~ 103. 70% and 92. 50% ~ 117. 50%, respectively. This indicated that the method had good precision and high recovery rate. Using this method to determine the nicotine optical isomers of 26 different types of tobacco and tobacco products, it was found that tobacco was mainly S-( - )-nicotine, only 6 samples were detected by R-( + )-nicotine. The proportion of nicotine quality was 0. 18% ~0.70% ; among the 10 finished cigarettes and their mainstream smoke, the proportion of R-( + )-nicotine in total cigarette smoke was higher than that of cigarette tobacco. [ABSTRACT FROM AUTHOR]

Objective: To explore the application of microscope combined with radiofrequency coblation in the treatment of infantile epiglottic cyst. Method: 17 cases of infantile epiglottic cysts were treated with radiofrequency coblation under supporting laryngoscope and microscope. Result: All 17 patients were successfully resected the epiglottic cysts, without complications during and after surgery. The dyspnea symptoms disappeared at the time of discharge. The wounds healed well after reexamination at 1 month after operation. There was no recurrence in the 6-23 months follow-up. Conclusion: The treatment of infantile epiglottic cysts with radiofrequency coblation under microscope has many advantages, such as clear vision, strong three-dimensional sensation, stable operation of both hands, less bleeding, and light postoperative tissue reaction., 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.)

Objective: To summarize the effectiveness of bone cement combined with screws for repairing tibial plateau defect in total knee arthroplasty (TKA)., Methods: Between March 2013 and March 2016, 30 patients were treated with TKA and bone cement combined with screws for repairing tibial plateau defect. Of the 30 patients, 8 were male and 22 were female, with an average age of 64.7 years (range, 55-71 years). And 17 cases were involved in left knees and 13 cases in right knees; 22 cases were osteoarthritis and 8 cases were rheumatoid arthritis. The disease duration ranged from 9 to 27 months (mean, 14 months). Knee Society Score (KSS) was 41.63±6.76. Hospital for Special Surgery Knee Score (HSS) was 38.10±7.00. The varus deformity of knee were involved in 19 cases and valgus deformity in 11 cases. According to the Rand classification criteria, tibial plateau defect were rated as type Ⅱb., Results: All incisions healed by first intention, without infection or deep vein thrombosis. All the patients were followed up 27.5 months on average (range, 10-42 months). At last follow-up, HSS score was 90.70±4.18 and KSS score was 93.20±3.75, showing significant differences when compared with preoperative values ( t =-58.014， P =0.000; t =-60.629， P =0.000)., Conclusion: It is a simple and safe method to repair tibial plateau defect complicated with varus and valgus deformities with bone cement and srews in TKA.

Objective: To explore the characteristics of post-operative pain following coblation tonsillectomy and/or adenoidectomy in children with sleep-disordered breathing (SDB) and explore the correlation between the first day post-operative pain scores and age and operating time., Method: 1) A total of 113 SDB children scheduled to undergo coblation tonsillectomy and/or adenoidectomy were recruited. 113 children were divided into two groups according to the method of operation, children who underwent coblation tonsillectomy and adenoidectomy were enrolled in study group one and children who underwent coblation adenoidectomy only were in study group two. Be sides, children of study group one with a history of chronic tonsillitis were in chronic tonsillitis group, children without a history of chronic tonsillitis were in non-chronic tonsillitis group. 2) The parents scored pain in their children on a VAS (anchored by "no pain" at 0 and "worst pain" at 10) in the morning, before using any analgesics and having breakfast, over the first 3 and the seventh post-operative days. 3) Post-operative pain scores were compared between both the study group one and two and chronic tonsillitis group and non-chronic tonsillitis group. Futhermore, the correlation between the first day post-operative pain scores and age and operating time were also analysed., Result: 1) The difference of post-operative pain scores over the first 3 and the seventh post-operative days were significant between the study group one and group two (P<0.05). 2) Non-chronic tonsillitis group were significantly less painful than chronic tonsillitis group on day 1, day 2 and day 7 (z=-2.004, -2.059, -2.334, P<0.05). But there was no significant difference in pain levels on day 3 (P>0.05). 3) The first day post-operative pain scores was correlated with age (r=0.273, P<0.01) and operating time (r=0.423, P<0.01)., Conclusion: The first day post-operative pain scores was correlated with age and operating time. Children with a history of chronic tonsillitis were more painful than children without the history.

Objective: To explore the effects of septonasal bidirectional mucoperiosteal flap in the treatment of refractory choanal atresia in adults., Method: Analysis of 9 cases for choanal atresia was conducted. Two cases were of congenital origin and 7 cases of acquired origin, which was a complication of radiotherapy for nasopharyngeal carcinoma. The patients received transnasal endoscopic surgery using the septonasal bidirectional mucoperiosteal flap, without positioning the postoperative expansion tube. After the operation, the changes of symptoms were observed and the recurrent rate of restenosis or atresia was investigated in the follow-up time., Result: The symptoms of nasal obstruction and mouth breathing improved significantly in the 9 patients. At an average follow-up time of 19.3 months, the new forming posterior nare remained patent. The mucoperiosteal flap had no shift or necrosis. No restenosis or atresia happened. Nasal adhesion occurred in two patients. Granulation tissue hyperplasia was found in 1 patient, who underwent endoscopic revision without recurrence., Conclusion: The application of mucoperiosteal flap in transnasal endoscopic surgery for the choanal atresia can reduce the incidence of restenosis or atresia. Postoperative expansion tube is not mandatory.

Objective: To study the mRNA expression of muscle phenotype and collagen of soft palate and pathology in obstructive sleep apnea hypopnea syndrome (OSAHS)., Method: We used the Real-time PCR to test the mRNA expression of soft palate muscle myosin heavy chain (MyHC) phenotype and collagen in 12 OSAHS patients and 8 control patients. We also distinguished the muscle isoforms I , II with ATPase staining, then counted the numbers of isoforms muscle fiber., Result: The mRNA expression of OSAHS group was more than control group in II A MyHC phenotype (P<0.01). The number of OSAHS group muscle fibre I isoform was less than control group with pH4. 3 ATPase staining (P<0.05)., Conclusion: Compare to control group, the enhancement happened in the mRNA expression of II A MyHC phenotype which can increase the velocity and power but de crease the enduring quality of muscle in OSAHS, and the reduce be in the I MyHC isoform of muscle fiber that can cause muscle velocity become slower and persistency become longer in OSAHS patients.

A method of off-line combination of liquid chromatography and capillary gas chromatography-mass spectrometry (LC-CGC/MS) was established for the analysis of volatile and semi-volatile compounds in tobacco. The separation mechanism of volatile and semi-volatile compounds was studied. An LC column of 250 mm x 2.0 mm packed with 5 microm amino-bonded silica was used as stationary phase for the separation. n-Hexane/dichloromethane/acetonitrile (90: 6.6: 3.4, v/v/v) was used as mobile phase. Five fractions from one LC run were collected in five nitrogen-blowing flasks, separately. The same fractions from 10 LC runs were combined together and concentrated to 1 mL by nitrogen blowing, and then were analyzed by CGC/MS. The column of DB-5MS (60 m x 0.25 mm x 0.25 microm) was used for CGC/MS analysis. Comparing with direct CGC/MS analysis of the same sample, the LC-CGC/MS system is suitable for a complex sample, and has a higher reliability of qualitative analysis.