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There are many fields involved in China’s industry, and the carbon reduction is urgent. Oxy-fuel combustion is the core process of carbon capture in combustion. Coupling fluidized preheating activation with industrial kilns oxy-fuel combustion is a new way to expand fuel adaptability and achieve carbon capture during combustion. This study uses a small-scale fluidized bed continuous feeding experimental platform to investigate the effect of C/CO2 molar ratio (CC ratio) on the fluidized preheating activation characteristics of raw semi-char (RC) by adjusting the feeding rate at a temperature of 1 050 ℃ and CO2 fluidized rate of 0.17 m/s. The gas composition and low calorific value are analyzed, and the CO2 reduction ratio is calculated. The specific surface area, pore structure and carbon frame structure of fine particle activated semi-char (FC) and large particle activated semi-char (LC) are characterized. The reactivity of RC and FC is evaluated using a high-temperature tubular furnace thermobalance at 1 300 ℃. The results show that the use of fluidized preheating activation technology has achieved the resource utilization of CO2 and produced rich-CO fuel gas. When the CC ratio increases from 1 to 4, the CO+H2 volume fraction in the gas increases from 69.24% to 79.08%, and the highest CO volume fraction of 68.96%, the CO2 volume fraction decreases from 29.48% to 20.13%, and the CO2 reduction rate increases from 50.37% to 57.56%. The low calorific value of fuel gas increases from 8.69 MJ/m3 to 9.83 MJ/m3, which is 1.55−1.88 times higher than the low calorific value of the fuel gas produced by the project as described in the reference. The produced fuel gas in this study is conducive to the ignition and stable combustion of the kiln system. As the CC ratio increases, the specific surface area of FC and LC first increases and then decreases. The highest specific surface areas of FC and LC are 291.21 m2/g and 477.15 m2/g, respectively, which are 48 and 78 times higher than the RC. FC and LC have rich microporous structures, and the degree of graphitization decreases while the active sites increase. The microporous area accounts for 54.93%−68.42% of the specific surface area. In comparison, LC has a higher specific surface area and incremental pore volume mainly due to its longer residence time in the reactor, which promotes the development of pores and forms a large number of micropores. The reactivity index R0.5 and the average mass reaction rate of FC obtained under different CC ratios are higher than the RC, which reveals the good reaction characteristics of FC. It can be predicted that FC will achieve an efficient conversion during the high-temperature gas-solid activated thermal fuel combustion process. This research proposes a new route of fluidized oxy-fuel preheating activation for carbon-based fuels coupled with oxy-fuel combustion of gas-solid activated fuel with high-temperature. The influence of CC ratio on the characteristics of semi-char at CO2 atmosphere with fluidized preheating activation technology is obtained. The positive role of CO2 as a carbon and oxygen carrier is revealed. The research results provide a data support for the application of fluidized preheating activation technology in the industrial kiln oxy-fuel combustion industry.

This study aimed to explore the physiological activity of phosphorylated soybean polypeptide chelated calcium (PSPCC) and improve its calcium chelation capacity. To be specific，the preparation process of PSPCC was optimized by single factor test and response surface methodology. And the effect of phosphorylated soybean peptide chelated calcium on osteoblast activity was evaluated by in vitro experiments. The results showed that, the optimum process of PSPCC was as follows: Mass ratio of sodium tripolyphosphate to soybean polypeptide 1:2, phosphorylation reaction temperature 52 ℃, phosphorylation reaction pH7.0, phosphorylation reaction time 9.7 h, mass ratio of phosphorylated soybean polypeptide to calcium chloride 2:1, chelation reaction pH8.0, chelation reaction temperature 50 °C, and chelation reaction time 1.5 h. The maximum calcium chelation amount of PSPCC was 107.25±0.10 mg/g under the above optimal conditions. The results of MTT assay showed that the relative proliferation rate of osteoblasts in the PSPCC group (group D) was 1.6 times that of the soybean polypeptide group (group A) (the third day). In particular, the ALP staining experiment showed that the positive rate of staining in group D was 33.6 times that of the blank group. In addition, the ALP activity of each sample was detected by the ALP kit on the 7th day, and the results showed that the ALP activity of the group D was 6.2 times that of the blank group. And it was found that the number of calcium nodules in the group D was 94 times higher than that of the blank group through the alizarin red staining experiment. It was reasonable that the preparation process of PSPCC was optimized by response surface methodology, which was preliminarily proved that PSPCC had a significant effect on promoting proliferation and differentiation of osteoblasts (P

BackgroundPapillary thyroid cancer is the result of a variety of pathogenic factors. The prevalence of papillary thyroid cancer varies greatly in different regions, and the disease is more harmful to women.ObjectiveThis study aims to explore the relationship between reproductive factors and papillary thyroid cancer, and to provide basic data for prevention and control of the disease.MethodsA 1∶1 age (±3 years) matched case-control study was conducted in 331 pairs of newly confirmed papillary thyroid cancer cases and controls from two hospitals in Shanghai from November 2012 to December 2013. Comparisons were made in the history of menstruation, pregnancy, gynecological and breast diseases, and other variables between the two groups.ResultsThe results of univariate analysis indicated that the proportions of education below bachelor degree, married, and mainly manual workers in the case group were significantly higher than those in the control group (P1 time (OR =2.490, 95%CI: 1.196-5.184; P=0.015), and the history of using oral contraceptive or hormone drugs (OR=2.389, 95%CI: 1.338-4.268; P=0.003) were the risk factors of papillary thyroid cancer.ConclusionIrregular menstruation, surgical menopause, history of pregnancy, and history of using oral contraceptive or hormone drugs might be the risk factors of papillary thyroid cancer. To reduce the incidence of papillary thyroid cancer, strengthened health education and rational use of contraceptives are recommended.

Large numbers of redundant control packets produced by connectionless UDP flows may engender serious influence over the performance of the SDN controllers and networks.The endangerment of the redundant control packets for the performance of SDN controllers by testing and modeling was firstly analyzed,and then a basic solution to solve the problem was formed.Therefore,a preinstalling flow-tables ＆amp; filtering redundant packets (PFFR) mechanism was proposed.By preinstalling flow tables,PFFR limited the initial rate of control packets in UDP flows,and through installing flow tables according to paths and utilizing the redundant packets filtering algorithm,PFFR eliminated redundant packets rapidly.A prototype system based on PFFR was implemented and tested.The experimental results prove that the PFFR mechanism can effectively improve the performance of the controller.

In the present paper,the relevant provision in the ASME Code Case about"Applicability of the ASME exemption curve for Chinese pressure vessel steel Q345R"has been analyzed by using failure assessment procedure on the basis of true material testing data. For the normalized Q345 R investigated in this paper,the results indicated that both Charpy impact toughness and fracture toughness at low temperature are better than the requirements in ASME Code,the provision in ASME Code classifying Q345 R in Exemption curve A excessively underestimated the toughness of the material.

In this study, supercritical CO2 extraction conditions for sea cucumber powder were optimized using single factor and orthogonal experimental design, with defatting rate as an indicator. The fatty acid composition of the sea cucumber powder before and after extraction as well as that in the supercritical CO2 extract were detected using gas chromatography, and supercritical CO2 extraction of volatile flavor substances was investigated using headspace-gas chromatography-ion migration spectroscopy (HS-GC-IMS). The results showed that the optimal conditions for supercritical CO2 extraction was optimized using single factor and orthogonal experiment, with an extraction temperature of 60 ℃, extraction pressure of 40 MPa, extraction time of 2 h, and a degreasing rate of 57.6%±3.89%. A total of 25 fatty acids were detected in the sea cucumber powder, extracted sea cucumber powder, and supercritical CO2 extract, with a higher proportion of monounsaturated fatty acids in the supercritical CO2 extract. In contrast, the proportions of polyunsaturated fatty acids such as arachidonic acid (ARA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA) were higher in the extracted sea cucumber powder. HS-GC-IMS led to the identification of 70 volatile components. Notably, substances with fishy or pungent odors such as dimethyl sulfide, butanal, E-2-butenal, pentanal, heptanal, benzaldehyde, pentanol, 2-butanone, 2-hexanone, 3-hexanone and other substances were significantly reduced in the extracted sea cucumber powder, substantially improving the overall flavor. Therefore, supercritical CO2 extraction can effectively separate lipids from sea cucumber powder, while removing a large amount of volatile components with fishy odors.

Cardiopulmonary exercise testing (CPET) refers to a method of measuring various indicators of the human body under gradually increasing exercise loads to objectively evaluate cardiopulmonary reserve function and exercise endurance. Currently, CPET detection systems primarily measure subjects' ECG, respiratory flow, oxygen (O2), and carbon dioxide (CO2) parameters. This paper introduces a non-invasive multi-parameter exercise cardiopulmonary function evaluation system that incorporates impedance cardiography monitoring. The system integrates impedance cardiography monitoring with conventional CPET detection parameters and detects changes in the hemodynamic parameters of the body during exercise, aiding in the evaluation of exercise capacity. Additionally, the system features a portable design with Wi-Fi wireless transmission, which enhances its applicability.

Multi-wire swing reciprocating sawing technology is the main machining method used to cut sapphire crystal bars into wafer substrates, while normal force is an important index that reflects the processing stability. In this paper, the normal force（\begin{document}$ {F}_{\mathrm{n}} $\end{document}）during multi-wire swing reciprocating wire saw cutting sapphire crystal bars was measured, and the change in normal force at different positions and cutting depths of the sapphire crystal bars was tracked. The influence of various process parameters on the stability of the machining process was tracked by using the rangeability of normal force（\begin{document}$ \mathrm{\Delta }{F}_{\mathrm{n}} $\end{document}）as the index. The experimental results show that \begin{document}$ {F}_{\mathrm{n}} $\end{document} is closely correlated with the reciprocating motion of the wire saw and the rocking motion of the workpiece, and Δ\begin{document}$ {F}_{\mathrm{n}} $\end{document} in the front of the sapphire crystal bar is significantly different from that in the middle and back. Process parameters such as the wire saw speed（Vs）, maximum swing angle (θmax), single piece wire consumption (Md), tensioning force (Fw), and total cutting time (T) have different effects on Δ\begin{document}$ {F}_{\mathrm{n}} $\end{document}. The fluctuation degree of Δ\begin{document}$ {F}_{\mathrm{n}} $\end{document} is closely related to the wear of the wire saw.

Developing lithium-ion batteries (LIBs) with higher energy densities has been necessary in recent years to satisfy the increasing requirements of the energy storage and conversion fields. The limited performance of LIBs stems from their low available capacities and cycling stability. As one of the most important components of LIBs, the cathode material plays an essential role in determining the energy density and cycling stability of LIBs. Among the cathode materials, lithium-rich manganese-based materials are considered to be promising cathode materials for the next generation. This is due to their high specific capacity (theoretical capacity > 250 mA·h·g−1 for 1 Li+ extraction and approximately 378 mA·h·g−1 for 1.2 Li+ extractions), high energy density (approximately 900 W·h·kg−1 vs Li metal), and low cost. Despite these advantages, one major weakness of xLi2MnO3·(1–x) LiMO2 is its intrinsically poor rate capability. This has been recently verified to be associated with the retardation of mass transport of the rearranged surface after activating Li2MnO3 at >4.5 V charge. This rearrangement causes a large capacity loss. In addition, these materials exhibit fragile surface properties at high potentials, erosion from the electrolytes, and dissolution of transition metal ions. In addition, the high working voltage not only ensures high energy density but also triggers a side reaction between the electrode material and the electrolyte. This leads to problems such as transition metal dissolution, surface cracks, and laminated structure collapse during the cycling process, limiting the material’s commercial application. Surface coating can effectively alleviate the side reactions between the electrode and electrolyte, suppress the dissolution of transition metals, and thus improve the material’s coulombic efficiency and cycling stability during cycling. Until now, there have been many reports on the surface coating modification of Li-rich manganese-based materials; however, there are few review reports in this field. This paper summarizes the structure and characteristics of Li-rich manganese-based materials and their problems during the cycle process. Furthermore, it introduces the latest progress in the coating modification of Li-rich manganese-based cathode materials and systematically describes the application of different coating materials, such as electrochemically active materials, non-electrochemically active materials, and conductive polymers. Moreover, this study addresses the coating methods of single-layer coating, double-layer composite coating, and in situ coating and further analyzes the failure and enhancement mechanisms of cycling stability of the modification methods and coatings. Finally, a future development direction for Li1.2Mn0.54Ni0.13Co0.13O2 (LMNC) materials and modification methods is envisioned. This result provides a reference for the practical application of Li-rich cathode materials.

P110 steel, renowed for its good comprehensive mechanical properties, is widely used as casing in oil and gas wells. However, it is seriously worn when using cemented carbide tools to drill it underwater. The study delves into the experimental exploration of the wear ratio of P110 steel during underwater drilling using three different kinds of super-hard abrasive grains and binders. The investigation includes tracking and observing the morphological changes of abrasive grains on the core drill's surface, along with the analysis of graphitization on the surface of diamond abrasive grains. The results show that under the same processing conditions, the end wear of the three different core drills is roughly the same. However, the side wear of the core drill using diamond abrasive particles is significantly less than that using cubic Boron Nitride (cBN) abrasive particles. Under the condition of underwater machining, the end face diamond abrasive grains will produce graphitization. Despite this, the diamond abrasive grains still maintain a certain cutting ability. The hardness of the bonding agent affects the exposure of abrasive particles, which results in the difference in the performance of the core drill under different working conditions.

Objective To analyze the cost and effectiveness of different HIV screening strategies based on multi-center HIV residual risk study, so as to provide reference for blood centers to adopt appropriate HIV testing strategies. Methods According to the HIV screening and confirmation of blood donors in three blood centers in Anhui Province, the residual risk of different HIV screening strategies was estimated. A decision tree model was established to analyze the cost-effectiveness differences of three different screening strategies under current domestic policies. Results The residual risk of anti-HIV-1 +2 ELISA, HIV Ag/Ab1+2 ELISA and ELISA+NAT were 1.17×10-6,0.84×10-6 and 0.59×10-6, respectively. According to decision tree model analysis, HIV Ag/Ab1+2 ELISA had a cost-effectiveness advantage over anti-HIV 1+2 ELISA when there was no NAT, but the advantage of HIV Ag/Ab1+2 ELISA disappeared when there was one NAT. The cost of HIV reagents, the cost of HIV treatment and the cost of false positive discarding were sensitive factors of the model. Conclusion In this area, one anti-HIV 1+2 ELISA combined with one NAT has a cost-effectiveness advantage. Blood centers need to confirm and evaluate the ELISA reagents used before conducting HIV screening. Under the premise of ensuring sensitivity, reagent cost and reagent false positive rate are the key factors.

To establish a method for the rapid detection of 17 colorants in meat products by ultra performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS), samples were homogeneously extracted with water, degreased with n-hexane, enriched and purified with weak anion solid phase extraction (WAX) column. The seventeen compounds were separated on ACQUITY UPLC HSS T3 column by the gradient elution using acetonitrile-5 mmol/L ammonium acetate solution as mobile phase, detected by MS/MS with negative mode in multiple reaction monitoring (MRM) mode, and finally quantified by external standard method. The correlation coeffcients (r) of the seventeen compounds were above 0.99 in the mass concentration ranging from 20~1200 μg/L. The limits of detection and the limits of quantification of the method were 0.01~0.05 mg/kg and 0.03~0.15 mg/kg, respectively. The recoveries of seventeen analyses spiked at three levels (0.15, 0.30 and 1.0 mg/kg) in meat products ranged from 71.2% to 103.5% with the relative standard deviations (RSDs, n=6) ranged from 1.3%~4.9%. The method was easy to operate and with good purification effect. It could be applied to the rapid determination of the synthetic colorants in meat products.

With the growing demand for a natural deodorizer, ginger, garlic and coriander extracts were proposed to remove the fishy smell of tilapia fillets. The effects of different concentrations of ginger, garlic and coriander extracts on the fishy smell value, fat oxidation and total bacterial count of tilapia fillet were studied by single factor experiments. Then the proportion of the three extracts was optimized by response surface test. The results showed that ginger, garlic and coriander extracts at concentrations of 6~8 g/L could effectively reduce the fishy smell value of fresh tilapia fillets and inhibit the production of fishy smell during cold storage. All of the three extracts could significantly inhibit the increase of thiobarbital acid value at concentrations of 8 g/L and the garlic extract had better inhibition effect. Ginger, garlic and coriander extracts could effectively reduce the total bacterial count of tilapia fillets during cold storage at concentrations of 8, 8, 10 g/L respectively. The antibacterial effect of garlic extract was better than the other extracts. The optimum compound concentrations of the three extracts to remove the fishy smell were as follow: 8.9 g/L of ginger extract, 7.5 g/L of garlic extract and 5.8 g/L of coriander extract. The fishy smell value of fresh tilapia fillet was 0.42 in this optimum formula. The compound combination of ginger, garlic and coriander extracts had a better effect on removing fishy smell of tilapia fillet.

Objective To study the risk factors of blood donors confirmed to be positive for syphilis, so as to avoid highrisk groups, guide the recruitment of blood donors and improve blood safety. Methods From September 2021 to August 2022, 44 514 blood samples were screened using two enzyme-linked immunosorbent reagents for syphilis, and the reactive samples were confirmed by TPPA. Blood collection time, blood collection location, blood donation numbers, gender, age, marital status and educational level of blood donors were taken as the prediction risk factors, and factors with statistically significant differences by univariate Logistic regression analysis were further analyzed using multivariate factor Logistic regression analysis to determine the final independent risk factors. Results A total of 121 syphilis antibody reactive samples were detected by enzyme-linked immunosorbent assay, and 64 were confirmed positive by TPPA. Excluding those with incomplete information, a total of 44 505 blood donors were included in the analysis. Logistic regression analysis showed that there were statistically significant differences in blood collection location, blood donation numbers, age and education level. Conclusion Based on the analysis results of risk factors of syphilis positive blood donors in Wuhu, it is necessary to strengthen the consultation of blood donors in blood donation sites. The high-risk groups are first-time blood donors over 50 years old, with education level of junior high school or below.

[Objective] Numerous external interference signals exist in urban rail transit wireless communication system, posing a significant threat to operational safety. Targeting the issue of low identification accuracy due to the radiation source RF (radio frequency) characteristics susceptible to noise and interference, it is necessary to propose an individual identification method for communication radiation sources based on enhanced diagonal integral bispectrum. This method provides an effective new approach to ensuring the security of rail transit wireless communication systems. [Method] The data processing procedure and principles of DCLIB (diagonal-correlation local-integral bispectrum) are analyzed. The calculations for bispectrum transformation, enhanced diagonal integral bispectrum calculation, division of adaptive bispectrum integration interval, and radiation source identification method based on residual networks are explained. Simulation experiments are conducted using actual Wi-Fi (wireless fidelity) devices to analyze and compare the identification performance of the DCLIB method with that of other radiation source identification methods. [Result & Conclusion] The DCLIB method first estimates the bispectrum of communication radiation source signals and utilizes the autocorrelation characteristics of each parallel line on the sub-diagonals to form new spectral information for the enhancement of the signal subtle features. Subsequently, the method adaptively selects a reasonable spectral signal integration interval based on the spectral signal strength, reducing both noise impact and algorithm computational complexity. Thus, an enhanced diagonal integral bispectrum is obtained. The proposed DCLIB signal is then used as the RF fingerprint feature of the radiation source, and individual source identification is achieved using a deep residual network. Simulation identification experiments based on actual Wi-Fi devices demonstrate that the DCLIB method achieves the highest identification accuracy and exhibits excellent noise-resistance performance.

Objective To detect and analyze the infection status of HBsAg non-reactive /HBV DNA reactive blood donors by individual donor-NAT (ID-NAT) and chemiluminescence technology, and to explore the feasibility and potential risks of reentry. Methods The blood screening results of blood donors in Wuhu from January 2018 to October 2021 were queried by blood station information management software. The blood donation information of all HBsAg non-reactive /HBV DNA reactive blood donors was collected and then recalled by telephone. After informed consent, samples were taken for HBV DNA nucleic acid single test, enzyme-linked immunoassay for HBsAg, chemiluminescence assay for HBV seromarkers(including HBsAg, anti-HBs, HBeAg, anti-HBe and anti-HBc), and alanine aminotransferase (ALT) test. All the results were statistically analyzed. Results From January 2018 to October 2021, there were 142 051 donations, and the positive rate of sole HBV DNA was 0.06% (91/142 051), and 33 people (37 person-times) were successfully followed up. The yield rates of HBsAg, anti-HBs and anti-HBc were 6.06% (2/33), 39.39% (13/33) and 96.97% (32/33), respectively; None HBeAg was yielded. After two times of ID-NAT, 8 patients remained non-reactive to both systems, with a negative conversion rate of 24.24% (8/33). Meanwhile, 25 patients were at least once reactive to ID-NAT, and 23 of them were occult HBV infection with serologically reactivity. There were 2(6.25%) patients with HBsAg positive conversion and HBV DNA persistent reactivity, which were window period infection. One person was confirmed as false reactivity (no HBV infection) as he remained unreactive to both repeated ID-NAT and serological tests. Conclusion Chemiluminescence assay is more sensitive than ELISA in detecting HBV serum markers, which is beneficial to early detection of HBV samples in window period. The yielding rate of anti-HBc among HBsAg non-reactive/HBV DNA reactive blood donors detected by blood screening in this region is very high, and most of them are occulting infection, so the ID-NAT should be no less than 2 times in the reentry strategy.

Idiopathic pulmonary fibrosis (IPF) is a chronic progressive fibrous interstitial lung disease of unknown etiology. IPF is also considered to be among the independent risk factors for lung cancer, increasing the risk of lung cancer by 7% and 20%. The incidence of IPF complicated with lung cancer, especially non-small cell lung cancer (NSCLC), is increasing gradually, but there is no consensus on unified management and treatment. IPF and NSCLC have similar pathological features. Both appear in the surrounding area of the lung. In pathients with IPF complicated with NSCLC, NSCLC often develops from the honeycomb region of IPF, but the mechanism of NSCLC induced by IPF remains unclear. In addition, IPF and NSCLC have similar genetic, molecular and cellular processes and common signal transduction pathways. The universal signal pathways targeting IPF and NSCLC will become potential therapeutic drugs for IPF complicated with NSCLC. This article examines the main molecular mechanisms involved in IPF and NSCLC and the research progress of drugs under development targeting these signal pathways.

In order to study the grinding force of diamond wheel in axial feed grinding of cemented carbide, the transformation models of horizontal grinding force, vertical grinding force, normal force and tangential force are established, the variation of grinding force under different process parameters was measured, the effects of process parameters on normal force, tangential force and axial force are analyzed, the empirical formula of grinding force is established. The results show that in the process of axial feed grinding, the maximum grinding force is the normal force, and the axial force is slightly less than the tangential force. The influence of grinding wheel linear speed on grinding force in three directions is roughly the same. The influence of grinding depth on grinding force in three directions is obviously different. The effect of feed rate on grinding force is not significant.

Extraction of legal elements is an important basis for judicial intelligent auxiliary applications, and its purpose is to identify the key elements involved in the judgment document.In the past, extracting legal elements usually used multi-label classification methods for modeling.These methods mainly relied on the text features of the judgment document, thereby ignoring the label features.Besides, due to the imbalanced data problem in judicial data sets, the classification method will lead to poor model performance because of too many negative examples.To solve the above problems, a legal element extraction method based on BERT reading comprehension framework was proposed.This method constructed auxiliary questions with label information and legal prior knowledge, and used the machine reading comprehension model based on BERT to establish the semantic associations between question and judgment document.And this method added special tokens before and after the label in the question to enhance the learning ability of the model.Experiments were conducted on the legal element extraction data sets of the CAIL2019.Experiment results show that the performance is improved significantly, and the F1 value has been increased by 2.7%, 11.3%, and 5.6% respectively on the data sets of marriage and family case, labor dispute case, and loan contract dispute case.

In order to verify the applicability of epoxy-filled steel sleeves for reinforcement of the girth weld defects in X80 steel pipelines, X80 pipe fittings with 1 016 mm diameter were selected as the specimens and on the specimens two girth welds with same defects were set by manual welding. Definitely, one of the welds was reinforced with an epoxy-filled steel sleeve, while the other was not. Then, the full-scale mechanical tests were performed under the internal pressure, fluctuation pressure and the coupling effect of internal pressure and bending moment for the above two defective girth welds with/without reinforcement. In addition, the failure mode, bearing capacity and deformation performance of the two specimens were compared and analyzed. The results show that the hoop and axial stresses of the girth weld defects reinforced by the epoxy-filled steel sleeve under the operating pressure is reduced, and the sleeve shares 47% of the internal pressure. The stress of the girth weld defects reinforced by the epoxy-filled steel sleeves under the cyclic fluctuating pressure is kept unchanged, which indicates that the stress level of the sleeve reinforced girth weld defects is stable, without changing with the fluctuation of the pressures. In addition, under the coupling effect of the internal pressure and the bending moments, the failure mode of the unreinforced pipeline is overall fracture of the weld section, while the failure mode of the reinforced pipeline is local buckling failure in the pressure region after the yield of the steel in the tensile region, which indicates that the epoxy-filled steel sleeves increase the bending capacity of the pipelines and reduce the bending deflection. In brief, the research results can provide a reference to the engineering application of reinforcing the defective girth welds of X80 pipelines with epoxy-filled steel sleeves.

Objective To compare the polishing effects of three different polishing systems on machinable compos⁃ ite resins and to provide a basis for the rational selection of polishing systems in the clinic. Methods Block HC, Cerasmart, and Hyramic were fabricated into 90 test pieces. Then, 30 test pieces for each material were randomly divid⁃ ed into 3 groups with 10 pieces per group. The pieces were polished with the Vita Enamic® Polishing Set (Vita group), EVE RA341 composite polishing set (Eve group), and Toboo M elastic ceramic polishing set (Tob group). The surface roughness and gloss of each test piece after polishing were measured, and the surface morphology was observed using a scanning electron microscope. Results The surface roughness values of the Vita and Eve groups for the same compos⁃ ite material were significantly lower than those in the Tob group (P < 0.05). No significant difference was found between the Vita and Eve groups (P > 0.05). Lower roughness values could be achieved. The gloss values of the three composite resins in the same material group were in the order of Vita group > Eve group > Tob group, and the differences between the groups were statistically significant (P < 0.05). No significant differences in the surface roughness and gloss values were found among the different composite resins (P > 0.05). Scanning electron microscopy showed that the Vita group had fewer and lighter scratches on the surface and a more uniform texture. Conclusion The Vita Enamic® Polishing Set can be used to cut composite resin and yields the lowest roughness and highest gloss values with the best polishing effect. The same polishing system did not exhibit significant differences in the polishing effect for different machinable composite resins.

Background & Problems: Ventilator-associated pneumonia (VAP) is a common healthcare-associated infection in the intensive care unit. The average VAP rate was 1.28‰ in our unit during 2011. Therefore, we designed a project to identify relevant problems, including: inadequate knowledge about VAP care, incorrect techniques for sputum suction, patient head elevation < 30~45 degrees, ventilator humidiier installed with water equipment designed without water-resistant barriers, failure to change the resuscitator and small-volume nebulizer regularly, and possible cross-contamination between respiratory-care devices. Purpose: We targeted a VAP rate decrease from the current 1.28‰ to less than 1‰. Resolution: The improvement measures implemented included team resource management (TRM) with VAP education, promotion, a written reminder regarding sputum accumulation sites, instruction to elevate the head of patients to an appropriate height, introduction of an auto-stop water adding system, and regular changes of related devices at assigned positions. Results: The VAP rate decreased from 1.28‰ to 0.65‰. Conclusions: The risk identiication and associated TRM project improved teamwork and the quality of care in the ICU. [ABSTRACT FROM AUTHOR]

Coal samples from Southern Qinshui Basin were sampled, and experimental study on stress sensitivity under different experimental condition was performed, in order to analyze stress sensitivity and affecting factors on permeability of coal reservoir at different stage of coal-bed methane drainage. The results show that permeability of coal samples decline 50% -70% when the effective stress increase from 0 to 10 MPa, and the loss of coal reservoir permeability is about 10% when the effective stress increase from 10 MPa to 20 MPa. The stress sensitivity of coal samples are relatively stronger when the effective stress is below 2.5 MPa. The damage coefficient of permeability increase quickly and the loss of permeability is about 20%-30% of the initial permeability from coal samples when the effective stress increase to 3.5 MPa. The stress sensitivity is strongest when the effective stress increase from 2.5 MPa to 9 MPa. The damage coefficients of permeability decrease quickly and the initial permeability from coal samples lose 60% when the effective stress increases from 3.5 MPa to 9 MPa. The damage coefficient of permeability decrease slowly and the loss of permeability is about 10% of the initial permeability from coal samples when the effective stress beyond 9 MPa. The damage rate of permeability from coal samples is between 30% and 65%, and the critical stress is 7 MPa to 11 MPa. The permeability of coal samples increase with increase of pore pressure, when the effective stress is relatively lower and constant. The permeability of coal samples decrease with the decline of effective stress and increase of pore pressure when the confining pressure is constant, which is related to the variation of permeability caused by the variation of effective stress and pore pressure on coal reservoir. [ABSTRACT FROM AUTHOR]

Objective To investigate the application of neuroendoscopy and curative effect of lateral skull base surgery via transcranial approach. Methods Clinical data of 142 cases undergoing endoscopic lateral skull base surgeries via transcranial approach from July 2015 to July 2018 were retrospectively analyzed. There were 32 cases of primary hemifacial spasm, 56 cases of primary trigeminal neuralgia, 2 cases of primary glossopharyngeal neuralgia, 15 cases of epidermoid cyst, 14 cases of acoustic neuroma, 3 cases of trigeminal schwannoma, 18 cases of pontocerebellar trigone meningioma, and 2 cases of jugular foramen schwannoma. Among them, 90 cases (32 cases of primary hemifacial spasm, 56 cases of primary trigeminal neuralgia and 2 cases of primary glossopharyngeal neuralgia) underwent endoscopic microvascular decompression (MVD) via transcranial approach, and 52 cases (15 cases of epidermoid cyst, 14 cases of acoustic neuroma, 3 cases of trigeminal schwannoma, 18 cases of pontocerebellar trigone meningioma, and 2 cases of jugular foramen schwannoma) underwent endoscopic removal of lateral skull base tumors via transcranial approach. Results All the operations were performed under endoscopy, including 96 cases (67.61%) operated by single hand (the endoscope was held by a pneumatic arm) and the rest 46 cases (32.39%) operated by both hands. The cure rate of MVD was 87.78% (79/90) and the total removal rate of lateral skull base tumors was 90.38% (47/52). The mean follow-up period was (23.46 ± 8.93) months. There was no death or other serious complications. Conclusions The complex lateral skull base surgery via transcranial approach can be performed by neuroendoscope with pneumatic endoscopic fixed arm. It has the advantages of near and multi-angle observation, clear visual field, full exposure and high recognition of nerve and blood vessels. However, the requirements for endoscopic technology, instruments and assistive equipments are high, and it is necessary to receive relevant trainings and experiences in endoscopic surgery. DOI: 10.3969/j.issn.1672-6731.2019.03.008

In the mobile network environment,the mobile honeypot resources are limited and the attack injection means are flexible,so it is necessary to dynamically deploy the honeynet to collaboratively detect the attack behavior characteristics.However,existing honey nets are susceptible to feature recognition attacks,malicious traffic within the network,and can’t be migrated across honeypots.Based on software defined networking (SDN) technology,an intelligent collaborative honeynet system (ic-Honeynet) was designed.It consisted of a reverse connection proxy module and a honeynet controller.Finally,an ic-Honeynet experimental environment was built and the effectiveness of the system was verified.The experimental results show that the throughput of the system is nearly linear,up to 8.23 Gbit/s; the additional increase in response delay is small,only in the range of 0.5 to 1.2 ms; the connection processing capability is also very strong,up to 1 473 connections/s.

Background and objective Lung cancer is the leading cause of cancer death in men and women in the world, more than one-half of cases are diagnosed at a advanced stage, and the overall 5-year survival rate for lung cancer is 18%. Lung cancer is divided into non-small cell lung carcinoma (NSCLC) and small cell lung carcinoma (SCLC). Approximately 80%-85% of cases are NSCLC which includes three main types: adenocarcinoma (40%), squamous cell carcinoma (SCC) (20%-30%), and large cell carcinoma (10%). Although therapies that target driver mutations in adenocarcinomas are showing some promise, they are proving ineffective in smoking-related SCC. We need pay more attention to the diagnosis and treatment of SCC. 18F-FDG positron emission tomography (PET)/computed tomography (CT) has emerged as an accurate staging modality in lung cancer diagnosis. The aim of this study is to investigate the role of maximum standardized uptake value (SUVmax) on PET-CT in prognosis and its correlation with clinicopathological characteristics in resectable SCC. Methods One hundred and eighty-two resectable SCC patients who underwent PET/CT imaging between May 2005 and October 2014 were enrolled into this retrospectively study. All the enrolled patients had underwent pulmonary resection with mediastinal lymph node dissection without preoperative chemotherapy or radiotherapy. Survival outcomes were analyzed using the Kaplan-Meier method and multivariate Cox proportional hazards model. Correlation between SUVmax and clinicopathological factors was analysed using Pearson correlation analysis and Spearman rank correlation analysis. Results The patients were divided into two groups on the basis of SUVmax 13.0 as cutoff value, and patients with SUVmax more than 13.0 had shorter median overall survival than patients less than 13.0 in univariate analysis (56 months vs 87 months; P=0.022). There was remarkable correlation between SUVmax and gender, tumor size, tumor-node-metastasis (TNM) stage, neutrophil, NLR, hemoglobin (P

The core idea of SDN（software defined networking）is that the control plane and data plane are separated,which makes the network traffic can be flexible controlled.Since SDN has these characteristics,the traffic monitoring and control in SDN have significant differences with traditional IP networks.A network traffic monitoring and control system based on sFlow technology was presented.With the application of sFlow,the process of data collection was separated from the control plane of SDN.The experimental environment was constructed based on OpenDaylight controller and Mininet,and the abnormal traffic was simulated by DoS（denial of service）attacks.The experiments show that the proposed network traffic monitoring and control system can effectively intercept the abnormal traffic.

Industry and the Academia have carried out various kinds of network virtualization technologies to cope with the growing requirement of cloud network. The diversity in network virtualization technologies wi11 lead to the co-existence of various kinds of technologies in cloud environment. However，the differences among network virtualization technologies separate the overa11 network resources into several isolated“islands”. In order to solve the problem，a solution called network virtualization interconnection technology was introduced. The key challenges of realizing the interconnection were discussed，then a novel software defined networking based interconnection architecture Omni-Bridge was proposed. Finally，a prototype of Omni-Bridge was introduced and a functional validation experiment was presented.

In this study, three varieties of fresh bamboo shoots (Dendrocalamus brandisii, Dendrocalamopsis oldhami, and Phyllostachys edulis) were frozen by immersion quick-freezing (IF), liquid nitrogen spray quick-freezing (LNF), or pressure transfer quick-freezing (PSF). The effects of the three quick-freezing techniques on the freezing characteristics and quality of bamboo shoots were investigated. Among these quick-freezing techniques, LNF showed the best freezing efficiency with the fastest freezing rate. The freezing rates of D. brandisii, D. oldhami and P. edulis shoots were 12.43, 3.92 and 7.5 times higher than those of the slow freezing (SF) group, respectively. For all three bamboo shoots, the thawing loss was less than 2%; the hardness of quick-frozen samples increased by 47.26%–65.02%, and the total amino acid loss decreased by 7.88%–38.91% compared with the SF group. In addition, the proportion of free water in the LNF group was significantly lower than those in the other three groups, water was most tightly bound to the tissue, and the microstructure was most similar to that of fresh samples. IF had the second highest freezing efficiency. Although PSF performed best in maintaining the color and inhibiting the enzymatic browning of bamboo shoots, peroxidase (POD) and phenylalanine ammonialyase (PAL) activities were 27.76%–45.24% and 27.05%–80.86% lower in the PSF group than in fresh samples, respectively. In addition, the structure of vascular bundles was seriously damaged by PSF, resulting in 6.12%-10.47% thawing loss and more serious water migration. In conclusion, LNF performed best in terms of freezing rate and quality maintenance, and could be the most suitable method for the quick freezing of bamboo shoots among the three quick-freeze technique.

The purpose of this study was to screen potential anti-inflammatory peptides from Channa argus. Toll-like receptor (TLR)2 and TLR4 were chosen as the target proteins. Virtual hydrolysis was used to select the best enzyme for obtaining bioactive peptides from C. argus proteins. Anti-inflammatory peptides were selected by the combined use of physicochemical prediction, molecular docking, and a cell model, and their mechanisms of action were elucidated. The results showed that 109 bioactive peptides obtained with papain were not toxic, from which 34 highly water-soluble peptides were selected for analysis of adsorption, distribution, metabolism, excretion and toxicity (ADMET) properties. Peptides KF, PR, NC, YR, WEL, QWWR and DEECWF exhibited high-affinity binding to TRL2 and TRL4 mainly through hydrogen bonding. These peptides were found to increase cell viability and inhibit the overproduction of nitric oxide (NO) and inflammatory factors (tumor necrosis factor-α (TNF-α), interleukin (IL)-1β and IL-6) in lipopolysaccharide (LPS)-induced RAW264.7 cells, indicating their anti-inflammatory activity. This study revealed the interaction mechanism between the anti-inflammatory peptides and TLR2 or TLR4 targets and provides theoretical support for understanding the mechanism underlying the immunoregulatory effect of bioactive peptides from C. argus.

Background Community health services play an effective role in delaying the progression of diabetes and managing diabetes complications. Previous studies have suggested that the subjective experiences of visits to community health centers by patients with diabetes contributes to their improved health outcomes. However, few studies have evaluated the correlation of glycemic control outcomes with specific service processes and objective experiences of programs received by diabetic patients in the community health service centers. Objective To explore the correlation between the community health service experiences and glycemic control outcomes in patients with diabetes mellitus. Methods A cross-sectional survey design and multi-stage, cluster random sampling method was used to select six community health service centers in the central urban area of Guangzhou, with one family doctor team randomly selected from each center. A total of 336 patients with diabetes who visited the corresponding family doctor teams from September to November 2019 were recruited as the study subjects. A questionnaire was conducted to collect baseline information, fasting plasma glucose (FPG) level, and Primary Care Assessment Tool (PCAT) scores. The glycemic control outcomes of patients were assessed based on the FPG level, and their experiences of community health services were assessed based on the PCAT scores. Logistic regression models were used to evaluate the effect of community health service experiences on glycemic control outcomes in diabetic patients. Results The glycemic control rate of the included diabetic patients was 73.2% (246/336). The total PCAT score and the scores for each dimension of PCAT with good glycemic control outcomes were higher than those of patients with poor glycemic control outcomes, and the difference was statistically significant (P

Among cancer survivors who are characterized by poorprognosis and quality of life, there is a high prevalence of sedentary behavior, which is closely associated with adverse outcomes, requiring urgent attention. Based on this, we reviewed the latest advances in sedentary behavior among cancer survivors, including relevant theories, assessment methods, influencing factors, association with prognosis and intervention, and concluded that sedentary behavior that sedentary behavior is a major risk factor for poor prognosis in cancer survivors, and single physical activity intervention or a combined intervention of physical activity and sedentary behavior is effective intervention. Additionally, given the situation where there is an urgent need to manage sedentary behavior in this group, indigenized studies ought to be carried out actively to make some improvements in their prognosis.

Currently, it is most economical to transport hydrogen with the existing natural gas pipelines by blending it into the natural gas among the storage and transportation technologies of hydrogen energy, and thus the transportation technology of hydrogen-blended natural gas is widely concerned by research institutes at home and abroad. However, hydrogen embrittlement may be caused to the pipeline steel due to the contact of hydrogen with base metal during hydrogen transportation, which further leads to the deterioration of mechanical properties of pipeline steel, threatening the safe operation of pipelines. Therefore, the change law of the mechanical properties of X52 and X80 steel typically used for natural gas pipelines under the actual hydrogen-blended conditions was studied through in-situ tensile testing and fracture morphology analysis under the environment of high-pressure gas-phase hydrogen. Meanwhile, the influence of hydrogen partial pressure on yield strength, tensile strength, percentage reduction of area and hydrogen embrittlement index of material was analyzed. The study results show that, the ductility of X52 and X80 steel is declined and the hydrogen embrittlement is intensified with the increasing of hydrogen partial pressure. Compared with X80 steel, X52 steel is more suitable for the hydrogen-blended natural gas transportation. Generally, the study results could provide reference to the material selection and safe operation of hydrogen-blended natural gas pipelines in the future.

To reduce the total cost of P2P cache system, a cooperative cache scheme based on the minimization of total cost is proposed. In the scheme, delivery cost and storage cost are taken into account, and inter-ISP cost, popularity, file size, storage cost are used to evaluate each object's caching gain value, which is a new concept defined to estimate the benefits of storing or replacing an object. When a replacement is needed, the objects with the minimum caching gain value will be evicted. Simulation results show that the proposed scheme can effectively reduce the total cost of P2P cache system.

The identity-based encryption based hidden credentials has three problems that it can not supports 1-N communication,endures no identity fuzzy and lefts open to conspiracy crack.An extended attribute encryption based hidden credentials model(EAEBHCM) was presented in to solve these three issued which making use of attribute-set certificates and decryption accuracy threshold characteristics.After analyzed the relevant research,the architecture,the system structure,the two sides trust negotiation protocol,multi-party trust negotiation protocols and how the model to solve complex logical access policies of the extended model were described in detail.And the security of extended model was also analyzed.Through a typical access control scenario,the difference between old and new hidden credentials technology on the performance and security were analyzed,which clarified the advantages of the extended model.

A transmission control protocol named TPSN(transmission control protocol for satellite networks)was proposed,which applied asynchronous hop-by-hop ACK,and SNACK based on checking window size to reduce overhead of control message and achieve reliable transmission.In addition,TPSN transmitted load information on the base of hop-by-hop scheme to maintain high network resources utilization,fairness among different data flows with heterogeneous RTT and congestion free.The good performance of TPSN,in terms of link utilization,transmission effectiveness and fairness,was verified via a simulated satellite network with high link error rate,large delay and intermittent links.

By defining the major types of managed objects and their relationships with each other, an information model for fault impact analysis of Internet services was proposed. The relationships also included those between the high-level service and the underlying IT infrastructure which realized the service. An experiment was given afterwards and the re-sults show that the model can be effectively used to analysis the impact of the fault in Internet services.

In order to analyze the effect of reservoir damage on the productivity of CBM wells during its production process, the Chengzhuang Block in Southern Qinshui Basin was investigated. The production characteristics of 22 CBM wells were analyzed and divided into high, medium, low productivity well and drainage well. Also, the occurrence time of the drainage damage of different production wells was defined. At the same time, the discrimination model of damage mechanism in die extraction process of CBM wells was established. The results show that the velocity sensitivity effect is easy to occur in the early stage of the production, and the peak period of gas lock appears in its middle stage, and the stress closure damage occurs in its late stage. In the above damages, that always occurs in high to low productivity wells in Chengzhuang Block, the possibility of gas lock is higher than that of the velocity sensitivity effect, while the velocity sensitivity effect occurrence probability is higher than that of the stress closure. The high productivity well usually results in one type damage during its production process, and the medium productivity well has a higher chance to occur two types damages, while the low well and drainage well normally result in a variety of damage types combination and even have the damage coupling effect. [ABSTRACT FROM AUTHOR]

Production characteristics of coal bed methane(CBM) wells in Fanzhuang block were studied. Geologic factors that affect divergences of water production and gas production between CBM wells were analyzed on the basis of geologic information and production data of 16 CBM wells. Geologic control mechanisms of the divergences were further studied. The results show that, in well dewatering stage, ground water fluid potential controls water production of CBM wells by affecting the flow directions of water and moisture content of coal bed reservoir. Permeability controls water production by affecting the flow capacity of water in coal bed. The negative correlation between ground water fluid potential and permeability accelerates the divergences of water production between CBM wells. In gas production stage, the decompression effect controls the divergences of water production and gas production by affecting the amount of de-sorption methane, saturation degree and effective permeability of water and gas in coal bed. If adjacent CBM wells are connected, gas/water separation in coal bed further accelerates the divergences of water production and gas production between CBM wells. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the effect of hydrogen rich water on experimental gingivitis in SD rats during pregnancy., Methods: Female SD rats mated with male ones were chosen to induce experimental gingivitis after ligation for 2 weeks. The pregnant rats were randomly divided into control group, model group and HW group. In the control and model group, rats were given pure water, while animals in the HW group were given hydrogen-rich water twice a day. All pregnant animals were sacrificed on day 16 of pregnancy. The level of Prog, SOD and TNF-α in the gingiva of different groups were measured by ELISA, the expression of PR, NFκB and TNF-α were determined by immunohistochemistry and Western blot. SPSS 13.0 software package was used for data analysis., Results: Pregnancy gingivitis of SD rats could be induced by thread ligation. PR was mainly distributed in the gingival epithelium, while there was no significant difference of Prog and PR in the gingiva among different groups(P>0.05). Furthermore, in the model group, lower SOD level as well as higher NFκB and TNF-α level were found in the gingiva. Compared with the model group, the inflammatory response of pregnancy gingivitis in HW group was significantly suppressed along with decreased NFκB and TNF-α., Conclusions: Progesterone and its receptor may play an indirect role in the process of pregnancy gingivitis of rats. Hydrogen rich water may be beneficial in suppressing pregnancy gingivitis progress by decreasing inflammatory response related to gingival oxidative stress.