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The ends of deep-sea submarine pipelines are usually connected to wellheads, suspended chain line risers, pipeline end manifolds, etc. , and the boundary conditions at the end of the pipelines are complicated. In order to investigate the influence of different pipeline boundary conditions on pipeline walking behaviour, the boundary conditions at the end of the submarine pipelines were simplified into three types: type Ⅰ is horizontal force at both ends, type Ⅱ is horizontal force at one end and inclined force at the other end, and Type Ⅲ is elastic boundary at one end and horizontal force at the other end; Numerical models of submarine pipeline walking were set up with different boundary conditions, and the behaviour of submarine pipeline walking was comparatively analyzed with the different types of boundary conditions. The results indicate that: compared with type Ⅰ, with the increase of pipeline end tension inclination angle, the pipeline axial tension decreases, and the amount of pipeline walking also decreases in type Ⅱ boundary conditions; With the pipeline tension inclination angle increased from 0° to 60°, the maximum axial tension decreases by 6.73%, and the pipeline walking rate decreases by 50%. This means that the change of the riser shape of the suspension chain line leads to the direction of the tension force acting on the submarine pipeline changes, and the amount of submarine pipeline walking also corresponding change. The comparison between type Ⅲ and type Ⅰ boundary conditions shows that the submarine pipeline walking rate under type Ⅰ boundary conditions is a constant value, with the number of heating and cooling cycles increase, the submarine pipeline walking rate is approximately linear growth; the submarine pipeline walking rate under type Ⅲ boundary conditions is influenced by the pipeline end manifolds elastic stiffness, the greater the elastic stiffness, the greater the walking rate of the pipe line in the first temperature cycle; with the number of heating and cooling cycles increase, the walking rate decreases rapidly until it reaches 0. The amount of pipeline walking under type Ⅲ boundary conditions is usually smaller than that of type Ⅰ. The walking behaviour of submarine pipelines varies greatly under the three types of boundary conditions, which provides some reference for analyzing the types of boundary conditions at the end of submarine pipelines and selecting appropriate boundary condition in actual project.

Plant polyphenols are a class of plant secondary metabolites containing several phenolic hydroxyl groups in their molecular structure, which have physiological properties such as anti-inflammatory, anticancer, antibacterial, etc., and can be used as excellent dietary supplements. However, some of the polyphenols are poorly stabilized, and they are prone to degradation during food production, processing, and storage, so it is necessary to use encapsulation technology to improve their stability and maintain their activity at the same time. The emulsion possesses the characteristics of stability and versatility with the potential to encapsulate and protect plant polyphenols. This paper firstly analyzes the properties of plant polyphenols and the underlying reasons for their limited applications, further discusses the encapsulation effect of different types of emulsions (normal emulsion, microemulsion, nanoemulsion, Pickering emulsion, multilayer emulsion and emulsion gel, etc.) on polyphenols, and finally summarizes the current status of polyphenol emulsion encapsulation systems in the food industry such as meat, fruits and vegetables, ice cream, bakery, and beverage, etc., and provides an overview of polyphenol emulsions in the future preparation direction and its development direction in the food field. This paper can provide some reference for the application of plant polyphenol emulsion encapsulation system in the future food industry.

As one of the main active ingredients of garlic, garlic polysaccharide has many biological activities, such as enhancing immunity, antibacterial, antiviral, antioxidant, hepatoprotective, hypolipidemic, hypoglycemic, etc., and has a broad application prospect. The extraction methods of garlic polysaccharides are most common by hot water method, enzyme method and ultrasound-assisted method. It is found by structural determination that garlic polysaccharide is a heteropolysaccharide composed of fructose, glucose, galactose, mannose, galacturonic acid, etc. Chemical modifications such as acetylation, selenization and phosphorylation can increase the antioxidant and other biological activities of garlic polysaccharide. This paper systematically summarizes the current research status of garlic polysaccharides from the perspectives of extraction, structure determination, chemical modification and bioactivity of garlic polysaccharides, and in the future, attention should be paid to the conformational relationship between polysaccharide structure and bioactivity, and the efficacy mechanism of garlic polysaccharides should be explored in depth, with a view to providing theoretical references for the development and utilization of garlic polysaccharides as functional products.

In order to predict the damage of submarine pipeline on saturated clay seabed by falling objects, a dynamic finite element model of interaction between saturated clay seabed and submarine pipeline under the impact of falling objects was established. The influence of six parameters, namely, energy of falling objects, diameter of the pipeline, wall thickness, grade of the steel material, internal pressure, and undrained shear strength of seabed soil on the damage of the submarine pipeline was analyzed by combining with the range of changes of the actual working conditions of the submarine pipeline. Taking the six parameters as input parameters, the damage of pipeline as output parameters, and the numerical simulation results as training samples, a BP neural network model for submarine pipeline damage prediction was constructed through learning and training. The results show that the larger the impact energy of the falling object is, the larger the pipeline damage is, and the pipeline damage growth rate tends to slow down with the increase in the impact energy of the falling object. The increase in pipeline diameter, wall thickness, internal pressure, and the pipeline yield strength leads to a decrease in the pipeline damage. The saturated soil undrained shear strength increases, while pipe damage increases. The established BP neural network prediction model for submarine pipe damage needs only six parameters, namely, falling object impact energy, pipe diameter, wall thickness, steel grade, internal pressure and undrained shear strength of seabed soil. It is simple and convenient, and can better predict the damage of submarine pipeline impacted by falling objects in saturated clay seabed. The numerical examples cover the working conditions of common saturated clay seabed submarine pipelines, so the model has good applicability, which provides new ideas for the prediction of submarine pipeline damage.

In this study, using Phellinus igniarius as raw materials, the extraction conditions of Phellinus igniarius polysaccharides were optimized, the structure and immune regulatory activity were analyzed and evaluated. Using extraction temperature, extraction time, solid-liquid ratio, and extraction frequency as factors, single factor experiments and orthogonal experiments were used to optimize the extraction conditions of polysaccharides from Phellinus igniarius. After purification by enzymolysis and dialysis methods, the structural features of this polysacharide were characterised using HPSEC (Mw), FTIR (functional group), HPAEC (monosaccharide composition) and methylation analysis (linkage patterns), and their immunomodulatory properties were investigated using RAW-Blue™ cell line. Results showed that, the optimal extraction conditions of polysaccharides from the fruiting body of Phellinus were as follows: The solid-liquid ratio was 1:40 (g/mL), the extraction temperature was 100 °C, the extraction time was 2.0 h, and the extraction times were 3. Under these conditions, the extraction yield of polysaccharide was 6.71%, the total sugar content was 81.69%±0.19%, and the Mw was 10.77 kDa. The polysaccharide obtained belong to glucan family constructing mainly by (1→4)-Glc, small percentage of (1→6)-Glc and (1→3)-Glc as side chains. This polysaccharide could enhance the embryonic alkaline phosphatase secretion activity and the phagocytosis ability of RAW-Blue™ macrophages, which would provide a theoretical basis for its application in both food and phamacetical area.

The deployment of network security has become a crucial strategy for the development of modern nations, with skilled professionals serving as the core driving force behind cybersecurity efforts.Cultivating cybersecurity talents and fostering team building are essential for China's talent reserves and strategic capital accumulation.With economic globalization, 0-day vulnerabilities have constantly emerged in information systems, attack chains have become increasingly complex, threat targets were difficult to detect, and hidden viruses varied over time.Talents trained by traditional universities for network security were unable to adapt to innovative production and practical activities in the new fields, as it was confined to their training structure system.In order to break through the shackles of the internal administrative structure and traditional curriculum system of universities, and ease the contradiction between the uncertainty of cyberspace security situation and the standardization of talent cultivation, the talent cultivation models based on Bourdieu's theory were studied, the fusion meaning of cultural capital in the academic field was analyzed and three practical standards were put forward in terms of teaching content, cultivation model and teaching opportunity of cyberspace security talents in combination with the actual cases of the “Fang class”.In terms of education content, standards and open knowledge systems were established to meet the differentiated needs of students.The mentorship approach was employed to construct habitus, fostering students’ ability to adapt flexibly to problems by adopting different cognitive thinking modes.Favorable teaching opportunities were utilized by tutors in various roles to promote efficient integration of individuals and fields, helping students establish a valuable and stable mindset.By leveraging Bourdieu's theory to explore the integration path of academic fields, it has leveraged the advantages of independently cultivating high-quality talents, vigorously promoting technological innovation and the healthy ecological development of the industry.

According to the latest 14th Five-Year Plan, China encourages the comprehensive utilization of mining resources such as associated ore, low-grade ore and tailings. Strengthening the comprehensive utilization of resources is an important means to change the extensive economic growth and realize the circular economy and green development. With the increasing demand for valuable metals such as zinc and lead and the depletion of limited high-grade zinc ore resources, it is urgent to comprehensively recover and utilize the valuable components of middle and low grade zinc oxide ore. In this paper, the existing technology principle, process flow and effect of the comprehensive utilization of low grade zinc oxide ore resources are summarized and analyzed from two aspects of roasting method and leaching method, and the problems existing in the application of each process are put forward. Secondly, the research status of comprehensive utilization of low grade zinc oxide ore and zinc containing waste by microbial hydrometallurgical technology is briefly analyzed. Finally, the prospect of the comprehensive utilization of low grade zinc oxide ore is prospected: the microbial hydrometallurgy technology, especially the microbial and chemical combined process technology, will be the focus of future research because of its characteristics of not only realizing the efficient recovery of valuable components, but also realizing the win-win of economic benefits and environmental protection.

Objective To analyze the causes of staff burnout and various errors during group blood donation in blood centers, and to explore the significance of overall planning to improve above problems. Methods Various errors occurred during group blood donation from January 2016 to December 2020 in a blood center were selected as the research object. Job burnout related survey data including emotional exhaustion (MBI-EE), work attitude (MBI-DP), sense of achievement (MBI-PA) etc. were collected. The influence of six variables, including blood collection quantity, staff, order control, plan compliance, overload blood collection and over-stock blood collection, on the occurrence of errors was analyzed, and an ordered logistic regression model was established. After optimizing overall planning measures, the occurrence of errors and the improvement of burnout were compared. Results In addition to the volume of blood collected (P>0.05), the other five variables had significant influence on the occurrence of errors (P0.05). Conclusion Scientific inventory management and effective blood collection assessment measures are helpful to improve work quality, and the ordered Logistic regression model has a good fitting degree for error rectification. Analyzing the occurrence of errors during blood collection and supply from the influencing factors is conducive to formulate corrective and preventive measures and promote the continuous improvement of work quality.

Jacking force is one of the most important parameters in the design and construction of pipe jacking. The accuracy of the jacking force will directly affect the success or failure of the pipe jacking project. Pipe jacking is increasingly applied to rock formations, but there are few calculation models for the jacking force in rock formations. To calculate the head-on resistance in the rock formation more accurately, a new calculation formula of the construction face resistance during pipe jacking is derived. The pipe jacking face is assumed to be stable; the rock pipe jacking force is analyzed by consideration of the rock breaking mechanism, force model and influence law of the rock pipe jacking machine cutter head hob. The results show that in rock pipe jacking, the compressive and shear strengths of the rock and the depth of the pipe jacking hob cut into the rock directly determine the value of the head-on resistance; after determining the appropriate hob spacing, the number of tools is not blindly increased; otherwise, the rock breaking effect of each hob will be affected. Moreover, the measured head-on resistance in engineering practice is consistent with the predicted value of the formula, which proves its applicability.

BackgroundAlthough transforming growth factor-β (TGF-β)/Smad signaling pathway is important in regulating the occurrence and development of pulmonary fibrosis, the pathogenesis of pulmonary fibrosis remains elusive. ObjectiveTo explore the functions of genes associated with TGF-β/Smad signaling pathway in the progression of pulmonary fibrosis. MethodsA NIH-3T3 fibroblast model induced by TGF-β1 was established. The experiment samples were divided into a control group and a TGF-β1 treatment group. The control group was exposed to normal saline, while the TGF-β1 treatment group was exposed to 10 ng·mL−1 TGF-β1 for 12 h. The RNAs of the two groups were extracted, sequenced, and analyzed by bioinformatics methods to identify seven key genes in TGF-β pathway, including Dcn, Smad3, Smad7, Fbn1, Thbs1, TGF-β1, and TGF-β3. The gene expression levels of five markers [Collagen1α1, Collagen1α2, α-smooth muscle actin (α-SMA), TGF-β1, and TGF-β3] and the seven key genes were detected by quantitative real-time PCR (qRT-PCR). The proteins of the two groups were extracted. The important marker protein expression levels of Smad3, the phosphorylation of Smad3 (P-Smad3), and α-SMA were detected by Western blotting. At the same time, 30 healthy SPF-grade C57BL/6 mice were randomly divided into three groups, with 10 mice in each group: a control group, a SiO2 inhalation exposure group for 28 d (10 mice), and a SiO2 inhalation exposure group for 56 d (10 mice). The mice in the two treatment groups were exposed to a natural SiO2 environment for 4 h per day with a 10-min pause for breathing fresh air at 2 h intervals. The lung tissues of the mice were taken after execution. The changes of pulmonary fibrosis were detected by Masson staining, and mRNAs and proteins were extracted to detect the expression of the above key genes and proteins. ResultsThe expression levels of the five marker genes Collagen1α1, Collagen1α2, α-SMA, TGF-β1, and TGF-β3 were significantly increased in the TGF-β1-induced NIH-3T3 fibroblasts than those in the control group (P < 0.01); the expression levels of P-Smad3 and α-SMA proteins increased significantly (P < 0.01); the expression results of the seven key genes screened in the TGF pathway were that Dcn and Smad3 were obviously down-regulated (P < 0.01), and Smad7, Fbn1, Thbs1, TGF-β1, and TGF-β3 were obviously up-regulated (P < 0.01). The changes in gene expression levels of the transcriptome sequencing showed the same trend. The results of Masson staining showed that the content of collagen fibers in the lung tissues also increased in the SiO2 inhalation exposure groups over time. In the mouse experiment, five marker genes were obviously up-regulated compared with the control group (P < 0.01); no obvious change was found in the expression of Smad3 protein, and the expression levels of P-Smad3 and α-SMA were obviously higher in the SiO2 exposure groups than those in the control group (P < 0.01); the expression levels of Dcn and Smad3 showed a down-regulated trend, while the expression levels of Smad7, Fbn1, Thbs1, TGF-β1, and TGF-β3 showed an up-regulated trend with the increase of SiO2 inhalation exposure days (P < 0.01). The expression levels of the above five marker genes, three important marker proteins, and seven key genes were consistent with the expression trends of TGF-β1-induced NIH-3T3 fibroblasts. ConclusionThe expression levels of pulmonary fibrosis-related marker genes and proteins change significantly in TGF-β1-induced fibroblast cells, and the lung tissues of mice under natural SiO2 inhalation exposure has obvious fibrosis characteristics. Seven genes (Dcn, Smad3, Smad7, Fbn1, Thbs1, TGF-β1, and TGF-β3) may be involved in the regulation of pulmonary fibrosis by the TGF-β/Smad signaling pathway.

As a kind of alkaline waste produced in the alumina production process, red mud has a high annual output, large stockpiles, and low utilization rate in this country, which poses a huge threat to the resources and environment. Extracting a large amount of valuable metal elements contained in red mud is of great significance for realizing the resource utilization of red mud. This article briefly describes the nature and composition of red mud. Research status and existing problems of extraction of valuable metal elements from red mud such as the direct magnetic separation, reduction-magnetic separation and wet processes of Fe, the reduction sintering method, calcification-carbonation method, acid leaching method and sub-molten salt extraction process of Al, fire and wet extraction process of Ti; and the combined fire-wet and wet extraction process of Sc were reviewed. TIt is believed that the current challenge for industrialized recovery of valuable metals in red mud lies in the complex composition of red mud, which leads to the technical difficulty and processing cost of valuable metal recovery, and the lack of process research on the systematic recovery of multiple elements. It is proposed that the development of more efficient technologies for the recovery of valuable metals and the strengthening of relevant research on the systematic extraction of multiple valuable metals from red mud are the keys to the realization of red mud resource utilization in the future.

Objective To investigate the effect of propofol (Pro) on cardiomyocyte damage induced by anoxia-reoxygenation through regulating JNK/p38 MAPK pathway. Methods Divided the cells into control group, anoxia-reoxygenation (A/R) group, anoxia-reoxygenation+propofol of low, medium and high dose (A/R+Pro-L, A/R+Pro-M, A/R+Pro-H) group, anoxia-reoxygenation+propofol+p38 MAPK pathway inhibitor (A/R+Pro+SB203580) group. Flow cytometry was used to detect cell apoptosis; Western blot was used to detect the expression of Bcl-2, Bax, cleaved caspase-3 and JNK/p38 MAPK signaling pathway related proteins; ELISA was applied to detect LDH content, MDA content, SOD activity and CAT activity. Results In A/R group Bcl-2 protein expression SOD and CAT activity were significantly inhibited cell apoptosis rate, Bax protein, cleaved caspase-3 protein expression, LDH, MDA, p-JNK protein, p-p38 MAPK protein expression were promoted(P＜0.05). Compared with A/R group, A/R+Pro-L group, A/R+Pro-M group, A/R+Pro-H group all showed significantly promoted cell Bcl-2 protein expression, SOD, CAT activity; inhibition of cell apoptosis, Bax protein, cleaved caspase-3 protein, LDH, MDA, p-JNK protein and p-p38 MAPK protein(P＜0.05). Compared with the A/R+Pro group, the A/R+Pro+SB203580 group showed significantly promoted cell Bcl-2 protein expression, SOD, CAT activity and inhibited cell apoptosis, p-JNK protein, p-p38 MAPK protein, Bax protein, cleaved caspase-3 protein, LDH and MDA (P＜0.05). Conclusions Propofol may slow down anoxia-reoxygenation induced cardiomyocyte apoptosis and oxidative stress through regulating the JNK/p38 MAPK pathway.

To investigate the oxidation combustion heat effect and thermokinetic behavior of lean coal, the pulverized coal samples were tested using C80 micro caloric system and thermogravimetric experimental device, respectively. The thermal effects of lean coal samples during the low-temperature oxidation and oxidation combustion were analyzed, and the influence of the heating rate on the combustion process of lean coal was also studied. In addition, the apparent activation energy and the most probable mechanism function of the coal sample during the combustion process were analyzed. The results indicated that the low-temperature oxidation process of lean coal pulverized coal could be divided into slow oxidation, accelerated oxidation and fast oxidation stages. Moreover, the five characteristic temperature points during the oxidation combustion of pulverized coal were determined by the variations of TG/DTG curves; with the increase of the heating rate, the TG and DTG curves of the coal sample shifted to the high temperature zone, and the peak value of the DTG curve increased with the ignition temperature increased; the apparent activation energy of coal sample in the pyrolysis combustion stage described a trend of first increasing and then decreasing with the increase in the conversion rate. The maximum apparent activation energy were observed when the conversion rate is 0.2, which was 32.4 kJ/mol; heating rates had tiny effect on the most probable mechanism function of the oxidation reaction. The most probable mechanism functions of the reaction under the four heating rates were all basically in line with the A-E equation random nucleation and subsequent growth model, and the peak value of the function curve increased with the heatingrate increased.

Oil and gas pipelines are one of the main means for oil and gas transportation over the world, and the development trend of their planning and construction is mainly affected by the development of oil and gas resources, as well as the national and regional energy policies. By quantitative and qualitative information mining, the global energy consumption structure and pipeline construction development in 2020 were sorted out, the current operation status of global oil and gas pipelines was analyzed, and the construction and development trend of global oil and gas pipelines in major regions of the world under the new situation was predicted. In the future, the construction of global oil and gas pipelines will be mainly affected by three factors: economy, politics and environment. It is predicted that the overall construction of global oil and gas pipelines will tend to be stable in recent years. Affected by the international environment, the construction progress of transnational pipelines is uncertain to a large extent, and fewer transnational pipelines can be completed and put into service on schedule. Besides, the pipeline construction in each country mainly depends on the economic development situation thereof. However, due to the dual impact of the economic downturn under the global COVID-19 pandemic and the energy transition under the guidance of "carbon peaking and carbon neutrality", it is expected that the local pipeline construction in the world will be concentrated in Asia-Pacific Region in the future. Meanwhile, the European and American countries and regions will explore to construct new hydrogen-mixed natural gas transportation pipelines or reconstruct existing gas pipelines for hydrogen-mixed natural gas transportation.(5 Figures, 3 Tables, 31 References)

Walnut shell (WS) was used as carbon source and KOH as activator. A series of activated carbon with different pore structures were produced by changing the mass ratio of KOH to carbonized precursor from walnut shell (KOH/carbonized precursor ratio), so as to reveal the relationship between the pore structure and the electrochemical performance. The result shows that the specific surface area, total pore volume, and percentage of mesoporous volume of activated carbon increased obviously with rising KOH/carbonized precursor ratio. Both the initial discharge specific capacity and the scaling performance of the composite cathode increased of first and then decreased slightly with the increase of specific surface area, total pore volume, and percentage of mesoporous volume. When the KOH/carbonized precursor ratio was 6∶1, WSAC-6/S with large specific surface area (3 913 m2/g), total pore volume (2.26 cm3/g), and percentage of mesoporous volume (59.4%) showed high initial specific capacity (1 397 mAh/g) and stable charge/discharge performance (869 mAh/g after 100 cycles at 0.2 C). Especially, at 0.5 C, it still exhibited excellent electrochemical performance, and the specific discharge capacity maintained at 707 mAh/g after 200 cycles.

Tetracyclines are a class of broad-spectrum antibiotics that have antibacterial activities against Gram-positive and Gram-negative bacteria, including Mycoplasma, Chlamydia, and Rickettsia. In this paper, we report the one-dimensional (1D) and two-dimensional (2D) nuclear magnetic resonance (NMR) studies on the exchangeable protons and hydrogen bound in tetracycline hydrochloride (TC). The NMR results were compared with the results obtained from the crystal structures of free tetracycline and RNA- and protein-bound complexes. The H-bonding frameworks in the drug and their correlation with drug activity were discussed. The1H and 13C NMR signals of TC and its derivatives were fully assigned and interpreted, and the misassigned signals in previous reports were corrected. The results of this study could be conducive to further exploration of the structure-function correlation of this drug family in more complex biological and environmental systems.

數位技術推動了外語讀寫教育發展，學習者的數位讀寫能力已成為二十一世紀公民必備技能之一。依據設計學習理論及數位讀寫理論，本研究從課程目標、教學法和評估標準層面構建了外語數位讀寫教學模式，並經由深度訪談對外語教師和第二語言學習者進行課程需求分析。本研究認為：一、當前數位讀寫任務設計的難點 在於課程整合問題。數位讀寫課程設置應打通課內及課外兩類資源，充分體現語言文化學習和數位資源使用的有機結合，引導學習者經由融合、互動和多模態進行自主學習和合作學習，最終實現課程資源優化配置；二、課堂教學需依託數位語境開展實踐活動，教師經由明確化指導和批判式教學，鼓勵學習者將新的知識遷移至數 位語境，發揮多媒體的促學效果；三、數位讀寫績效評估應同時兼顧語言目標、訊息目標、技術目標和關係目標的達成情況。 Recent advance in digital technology has promoted the development of digital literacy education in foreign languages; learners’ digital literacy has become one of the essential skills of citizens in the 21st century. Based on the theory of learning by design and digital literacies theory, this study attempts to construct the digital literacies teaching model from the curriculum, instruction and evaluation aspects. It is argued that the difficulty of current digital literacies task design lies on how to handle curriculum integration. Digital literacies courses should make use of digital resources available inside and outside the classroom contexts with reference to the unique features of language and culture. Through curriculum integration, interaction and multi-modal self-learning and cooperative learning, digital resources can be fully utilized. Moreover, classroom teaching should involve digital resources to enhance the language context. With explicit instruction and guidance, teachers should encourage learners to transfer their learning to the digital context. Lastly, evaluators should take into account the achievement of language objectives related to language, information and technology.

Background and objective Lung cancer is the most common malignancy and screening can decrease the mortality. High quality screening guideline is necessary and important for effective work. Our study is to review and evaluate the basic characteristics and methodology quality of the current global lung cancer screening guidelines so as to provide useful information for domestic study in the future. Methods Electronic searches were done in English and Chinese databases including PubMed, the Cochrane Library, Web of Science, Embase, CNKI, CBM, Wanfang, and some cancer official websites. Articles were screened according to the predefined inclusion and exclusion criteria by two researchers. The quality of guidelines was assessed by AGREE II. Results At last, a total of 11 guidelines with methodology were included. The guidelines were issued mainly by USA (81%). Canada and China developed one, respectively. As for quality, the average score in the “Scale and objective” of all guidelines was 80, the average score in the “Participants” was 52, the average score in the “rigorism” was 50, the average score in the “clarity” was 76, the average score in the “application” was 43 and the average score in the “independence” was 59. The highest average score was found in 2013 and 2015. Canada guideline had higher quality in six domains. 7 guidelines were evaluated as A level. Conclusion The number of clinical guidelines showed an increasing trend. Most guidelines were issued by developed countries with heavy burden. Multi-country contribution to one guideline was another trend. Evidence-based methodology was accepted globally in the guideline development.

Objective: To analyse the characteristics of the revision cochlear implantation （RCI）patients，the cause of the cochlear malfunction，and the choice of RCI operative approach. Method: A total of 39 patients with RCI were enrolled in this study. The cochlear use time, cause of failure and reoperation procedure are recorded and analyzed retrospectively. Result: There were 39 patients accepted cochlear reoperation，the ages ranges from 1 to 28，average age was 7.8 years, median age was 5 years old. The cochlear use time ranges from 1 month to 7 years，average was 2.2 years, median time was 1 year. Thirty-seven patients underwent RCI,30 cases right side and 7 cases left side. The reason of RCI contains device failure (28 cases)，infection (5 cases)，incorrect electrode implantation (3 cases)，facial nerve stimulation (2 cases)，and electrode prolapse (1 case).The choice of RCI procedure was dependent on the first operation procedure,contains facial nerve recess approach (35 cases) and mastoid approach (2 cases).Contralateral implantation was performed in 5 cases, the rest were ipsilateral. Conclusion: RCI has a variety causes and the common reason is trauma and device failure，the RCI should be completed as early as possible to avoid the ossified cochlear and hearing or speech stagnation，the electrode implantation through previous approach is the best method., 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 evaluate the operation safety, hearing as well as speech results of cochlear implantation that were applied in patients over 75 years old. Method: A series of patients who were diagnosed as severe to profound sensorineural hearing loss and received cochlear implantation were admitted. The clinical data and rehabilitation effects of the patients who were over 75 years old were summarized. Result: During this period, in which 7(1.31%) patients aged over 75 at implantation. The age ranged from 75 to 88, with an average of 80 years old. All of the 7 patients received a safe operation under general anesthesia. No major or minor complications happened related to surgery and anesthesia. Only one 84 years old male patient suffered from a transient mild balance problem. Follow up were carried out regularly, ranging from 4-40 months. The average of categories of auditory performance and speech intelligibility rating is 4 and 5 respectively. Conclusion: The cochlear implant surgery and general anesthesia are safe for patients over 75 years old, and these patients can benefit from cochlear implantation., 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 investigate the possible causes of non dry ear after canal wall down mastoidectomy(CWD). Method: Clinical data of 42 patients undergoing revision CWD in our hospital were analyzed retrospectively,which included history,symptoms,signs,audiological examination,imaging examination, intraoperative findings and postoperative follow-up.All patients underwent CWD and tympanoplasty under general anesthesia. Result: Twenty-six cases were insufficient opened of sinodural angle,36 cases remained mastoid air cell(9 cases is mastoid tip air cell remained),13 cases were inadequate exposured of anterior epitympanic recess, 23 cases were inadequate exposured of posterior tympanum, 25 cases had high facial ridge, posterior facial nerve and labyrinth air cell were 5 cases,3 cases had granulation in round window, 5 cases had dysfunctional eustachian tube, 32 cases had narrow external acoustic meatus. During 3 months,6 months and 1 year follow-up, all 42 cases patients under revision CWD presented with dry ears. Conclusion: Insufficient opened of sinodural angle and mastoid air cell,inadequate exposured of anterior epitympanic recess and posterior tympanum, high facial ridge, narrow external acoustic meatus are all the possible causes of no-dry ear after CWD; As the location of concealment, posterior facial nerve and labyrinth air cell are difficult to clean. The dressing cavity do not be cleaned in time after operation is also the underlying cause of postoperative non-dry ear., 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 clinical characteristics and therapeutic experiences of the middle ear teratoma in infants. Methods: Three cases of middle ear teratoma, from 2012-2015 in Beijing Friendship Hospital were analyzed. Results: The three cases all developed slowly and presented unilateral otorrhea and hearing loss. Otoscopy showed the granulation tissue in the external ear canal. Audiological changes varied according to the degree of severity. Imaging features showed the pocket-like occupancy lesions in the Eustachian tube area. The temporal bone CT showed mass with soft tissue density usually involved in the mastoid and tympanic cavity. MRI showed mixed signal intense on both T1 and T2 weighted imaging. All the three cases received neoplasm resection of the middle ear. Only one case received tympanoplasty surgery at the same time. And all the pathology results displayed mature teratoma. The follow-up time was 17 to 54 months. MRI showed complete removal of the tumor. Conclusions: Teratoma are rare in the head and neck neoplasm. When the infants suffer from the unilateral otorrhea, hearing loss, and granulation tissue formed in the external ear canal, it should be vigilant for teratoma. The differential diagnosis is middle ear cholesteatoma, congenital first branchial cyst or fistula, and middle ear carcinoma. Temporal bone CT combined with MRI could improve the accuracy of diagnosis. It should be totally resection as soon as possible if there is no contraindication. Postoperative follow-up and imaging examination are necessary to eliminate tumor recurrence.

Objective: To observe the clinical effect on the treatment of intractable tympanitis with reconstruction of external auditory canal wall. Method: Five cases underwent radical removel of residual lesion and reconsruction of external auditory posterior canal wall using hydroxyapatite ceramic wall with transferred pedicle temporalis fascia covering on it were analyzed. The implement of ossicular chain reconstruction depends on the probing for tympanic cavity intraoperatively. Periodic review were conducted in the 1st, 3rd, 6th, 12th month after surgery. Result: All 5 cases gained dryears within 3 months after surgery, in which hearing of 3 cases improved and ABG were within 20 dB. 1 cases showed no improvement compared to preoperation, and 1 case gained a worse audiology result. Central part of the transplant of 1 case was naked, while peripheral part had been epithelization and external auditory canal gained no accessible to mastoid cavity, the patient were also found recurrence of cholesteatom inside the mastoid cavity when received CT examination during outpatient follow-up one year postoperatively, and underwent correction surgery. 1 case underwent revision operation for a fistula between the reconstructed wall and the skin of the outer auditory canal. No surgical complications like infection or facial paralysis occurred, all patients were satisfied with surgery effect. Conclusion: HA with transferred vascularized temporalis fascia pedicle for the reconstructon of the external auditory canal wall is an effective method for the treatment of intractable tympanitis, and worth promoting., 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: The purpose of this study was analyzing the characteristic of the electrically evoked auditory brainstem responses (EABR) of cochlear implantation (CI) patients with absence of cochlear modiolus (ACM) and comparing the EABR results in deaf patients with normal anatomic structures. Also we assessed the auditory rehabilitation of ACM patients after cochlear implantation. Method: Twenty-eight profoundly deaf patients were contained, 14 of them were ACM (group A) and the rest were normal anatomic structures (group B). They all received Austria cochlear implants from 2004 to 2015. Postoperative EABR were measured and recorded with No. 2, 6, 11 electrodes in patients receving cochlear implantation. The lead-out rate and threshold of EABR between groups were compared and analyzed. Result: The lead-out rates of EABR in group A was 71.4% and group B was 100%. The thresholds of EABR in group A were higher than group B ( P < 0.05). In group A, there were no statistical difference in the thresholds of EABR among electrodes No.2,6 and 11. However, in group B, there were statistical difference in the thresholds of EABR between electrodes No.2 and 11 ( P < 0.05), and the thresholds of No.2 was lower than No.11 Conclusion: EABR could be used in assessing the objective auditory rehabilitation in ACM patients after cochlear implantation., 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 investigate the technique of the suprameatal approach for cochlear implantation in Chinese profound sensory hearing loss children., Methods: Suprameatal approach for cochlear implantation were used in 50 cases (total 53 ears) with profound sensory hearing loss from May 2005 to January 2007. The electrode was passed through the suprameatal tunnel and went between the incus and chorda tympani into the scala tympani., Results: Electrodes were completely inserted in 51 ears. There were no postoperative complications in all cases. Although the long effect need to be observed, all cases received better hearing and speech development benefit from cochlear implantation in the follow-up period. Among the 50 cases, 26 had speech perception in the open condition; 18 patients could speak short sentences although not clearly; and 6 patients learned to speak individual words only., Conclusions: The suprameatal approach was found to be a simple and safe technique that does not need mastoidectomy and avoid endangering the facial nerve and the chorda tympani. It enables wide exposure of middle ear and is especially suitable for cases with narrow facial recess or anteriorly located facial nerve.

Objective: To investigate the methods of preoperative diagnosis and differentiation of different pathological tissue in middle ear and mastoid., Methods: The temporal bone lamellar CT findings in 106 patients with chronic suppurative otitis media (including cholesteatoma) were retrospectively analyzed. The CT value of pathological tissue were measured for 183 times and were compared with the surgical findings and postoperative pathological findings to definitude the CT value range of different pathological tissue. Sixty patients taken from 106 patients at random were analyzed and made the diagnosis again by the same doctor team according to the CT value of the different pathological tissue and surrounding histoclasia resulted by pathological tissue. The diagnose accordance rate was compared with the routine diagnose report from radiology department. The predetective diagnosis was made in 10 patients with chronic suppurative otitis media according to clinical manifestation (pathological changes of tympanic membrane, nature of otorrhea, character of hearing), temporal bone lamellar CT finding (CT value of pathological tissue, surrounding histoclasia) to validate the value of this study for preoperative diagnosis and differentiation of different pathological tissue in middle ear and mastoid., Results: The CT value of cholesteatoma, granulation tissue, cholesteatoma combined with granulation tissue, effusion, calcified tissue, thickened and polypoid membrane was respectively (46.6 +/- 10.3) Hu, (26.6 +/-7.4) Hu, (42.1 +/- 11.4) Hu, (- 24.6 +/- 9.2) Hu, (223.6 +/- 63.7) Hu, (23.8 +/- 8.5) Hu. The diagnose accordance rate in 60 patients who were analyzed and made diagnosis again according to the CT value of the different pathological tissue and surrounding histoclasia resulted by pathological tissue raised from 68. 3% to 81.7% ( P < 0.05) . The predetective diagnose accordance rate reached at 90% according to clinical manifestation, temporal bone lamellar CT., Conclusions: It was not reliable to diagnose and differentially diagnose different pathological tissue in middle ear and mastoid only by the CT value, however, the CT value could still be considered to be a very significant information. The accurate rates of diagnosis and differentiation of different pathological tissue in middle ear and mastoid obviously raised by synthetically analyzing various kinds of pathological tissues in middle ear and mastoid according to clinical manifestation, temporal bone lamellar CT finding.

Chemical disposal was used to bring the activity group onto the surface of Kevlar fiber for the purpose of surface grafting modification. The interfacial constitution of the grafting of toluene-2,4-diisocyanate (TDI) onto Kevlar fiber was determined by Fourier transform infrared spectroscopy. In the mean time, hexyl-lactam stabilization and poly-glycol (400, PEG) stabilization on the grafted product were also studied. The effects of different nTDI:nPEG ratios on the production's interfacial constitution was analysed. It is concluded that the stabilization took place on the surface. The intensity of the bands relented at about 3300 cm(-1) and was reinforced at about 1700-1720 cm(-1) when the ratio of nTDI:nPEG = 1:3, but when the ratio is 1:1 and 1:2, the bands at about 3 300 and 1700-1720 cm(-1) are almost the same.

The mechanism of the modification of Kevlar fiber by polypropylene glycol(PPG) and cis-2-butene-1, 4-diol was studied in the paper, the authors learned the esterification of toluene-2, 4-diisocyanate (TDI) onto Kevlar fiber by infrared spectrum. In the mean time, the infrared spectrograms of the productions which steadily disposed by PPG and butendiol were analysed respectively, the result showed that the intensity of the bands was reinforced at about 1700-1720 cm(-1) after the samples were steadily disposed, that is to say, the group of --NCO has been stabilized into --NHCO group, the effect of steady disposal was obvious; but the disposal effect of butendiol was apparently better than PPG's at the same condition. Finally, the authors compared the influence of different mol rates between TDI and butendiol on the productions. Based onthe consequence, excessive butendiol would prevent the Kevlar fiber from farther reaction, therefore, the mol rate between TDI and butendiol should approach 1:1.

We have recentely built a cluster and backup system based on a SAN + NAS integrated storage system at a low price. The integration of SAN + NAS provides a storage system of fine quality, high reliability and high stability for hospitals. The article mainly introduces the choice of the project, the design of SAN + NAS integration and its implementation.

The chemistry organobentonites were synthesized by means of the ionexchange reaction between single-octadecyl trimethyl ammonium chloride(SOAC), di-octadecyl dimethyl ammonium chloride (DOAC) , tri-octadecyl methylammonium chloride (TOAC) quaternary ammonium salts and sodium base bentonies, respectively. The authors used FTIR, X-ray diffraction diagram and DSC thermograms to characterate the structure of the modified bentonites, and discussed the effect of different quaternary ammonium salt on the properties of organobentonites. The results showed that ion of the surfactants had entered into the chip layer of the bentonites, and changed the hydrophilic environment of the chip layer into hydrophobic environment and increased the distance among the chip layer, all of these had laid a base for the preparation of the nanometer composite material of high polymer/bentonite.

In the paper the authors tried to use chemical disposal to bring the activity mass onto the surface of Kevlar fiber with the purpose of surface graft modification. In the paper the authors used the FTIR spectra to discuss the graft of toluene-2, 4-diisocyanate onto Kevlar fiber. The authors studied and analysed the effect of hydrolytic time on the content of -O-H group of the production, and the effect of hydrolyzation and hexyl-lactam steadily disposing on the graft reaction. The result showed that the content of -O-H group increased after hydrolyzation, it's helpful for the graft reaction, and hexyl-lactam steadily disposing made the graf product more stable. Through the research the authors came to the conclusion that by bringing some activity masses onto the fiber surface the authors can improve the interface of fiber/resin effectively.

Objective: To evaluate the intraoperative obstacles and post-operative outcomes of cochlear implantation in children with enlarged vestibular aqueduct syndrome., Methods: Between May 1995 and June 2002, 10 patients with enlarged vestibular aqueduct syndrome received cochlear implantation in Pekin Union Medical College Hospital. The clinical records of 10 cases of enlarged vestibular aqueduct syndrome were analyzed retrospectively., Results: Via cochleostomy pulsatile clear fluid gusher occurred in 8 cases, which were easily controlled by quickly inserting the electrode array and sealing the cochleostomy with muscle tissue in each instance. The implant was inserted without difficulty in all patients. There have been no post-operatively complications, and audiologic outcome of the 10 patients with cochlear implantation were almost the same as the other patients without inner ear malformations. Five cases of them can even speak better than the other prelingual deafness that may be attributed in part to postlingual deafness., Conclusions: Despite pulsatile clear fluid gusher in cochlear implantation, no post-operatively complications have been found, and the outcome of these 10 patients with cochlear implantation was excellent. Cochlear implantation can be safely and effectively performed in patients with profound sensorineural hearing loss (SNHL) associated with enlarged vestibular aqueduct syndrome.

NADPH-Cytochrome P-450 Reductase is the major part of MFO (mixed function oxidase) system of liver. A simple and economic method of preparation of reductase was introduced in this paper and it was certified that xenobiotics benzene, bichloroethylene, and asbestos can be oxidized by reductase and reconstituted cytochrome P-450 2B1. But the metabolites of the 3 compounds can not cause the changes of plasmid PBR322 DNA.

The human embryonic lung fibroblasts transformation was induced by chemical mutant Glycidyl Methacrylate (GMA) in vitro. Transformed clonies were isolated and then exon 5 and exon 8 of p53 gene were specifically amplified by polymerase chain reaction. Amplified fragments were detected by using silver stained single strand conformation polymorphism analysis. The results showed that exon 8 altered in the transformed cells, indicating that p53 gene played an important role in the human embryonic lung fibroblasts transformation induced by GMA.