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ObjectiveTo analyze the predictive effect of miRNA-let-7 combined with serum markers on the chemotherapy effect and prognosis of glioma (GBM) patients. MethodsWe collected the data of 25 patients with GBM. Twenty healthy volunteers were included as the control group. Fasting serum samples were collected. The levels of let-7b, let-7d, and let-7e in serum samples were analyzed by quantitative real-time PCR. ResultsCompared with the control group, the levels of let-7b (192.5±18.71 vs. 98.13±11.68, t=6.42, P

BackgroundThe staff in centers for disease control and prevention (CDC) were at a great risk for psychological distress when they were faced with outbreak-related prevention and control work and routine tasks during the COVID-19 period. Psychological resilience and burnout are two key influencing factors on psychological distress. ObjectiveTo explore the status and mechanisms of psychological resilience, burnout, and psychological distress among CDC staff. MethodsFrom September to October 2022, a cross-sectional survey was conducted in all CDC staff in Beijing, and 2228 CDC staff from 17 units (including 1 municipality-level CDC and 16 district-level CDCs) participated the questionnaire survey. The basic information questionnaire, Connor-Davidson Resilience Scale (CD-RISC-10) Chinese version, Maslach Burnout Inventory-General Survey (MBI-GS) Chinese version, and the 10-item Kessler Psychological Distress Scale (Kessler10) Chinese version were selected in our study. Mann-Whitney U test or Kruskal-Wallis H test was used to analyze the differences in the scores of psychological resilience, burnout, and psychological distress by demographic and sociological characteristics. The correlations among the three elements were analyzed by Spearman correlation analysis. Potential influencing factors of psychological distress of the CDC staff were evaluated by multiple linear regression. A potential mediating effect of psychological resilience-burnout-psychological distress was analyzed by the mediation package of R 4.2.0, and validated by Bootstrap method. ResultsOf 2228 questionnaires distributed, 2022 valid questionnaires were collected, and the recovery rate was 90.75%. The median (P25, P75) psychological distress score of CDC staff was 13.00 (8.00, 24.00), and the number of participants with psychological distress levels of 1, 2, 3, and 4 was 358 (17.71%), 546 (27.00%), 362 (17.90%), and 756 (37.39%), respectively. The median (P25, P75) psychological resilience score was 24.00 (20.00, 30.00) and the median (P25, P75) burnout score was 38.00 (25.00, 50.00). The results of the multiple linear regression showed that psychological resilience, burnout, caring for the elderly, having a chronic disease, and monthly income had independent influences on psychological distress (P

Ultraviolet (UV) irradiation is an effective and broad-spectrum disinfection method. Conventional mercury vapor UV lamps are inexpensive and have been used most commonly, but there are shortcomings such as low irradiation, long disinfection cycle, and the generation of ozone. In recent years, the emerging UV disinfection technologies have shown great potential, thus domestic and international research institutions have conducted a number of studies on UV disinfection. In this review, we summarized the mechanism of UV damage to nucleic acids and proteins. Further, the effects of temperature, humidity and different media on UV disinfection technology were analyzed. Moreover, the safety, development status and future research applications of UV irradiation were clarified.

As an important microbial resource in the fields of food, agriculture and medicine, lactic acid bacteria have good development prospects. A long period of production experience has found that some important biochemical reaction process is difficult to complete by one bacterial starter during fermentation, and two or more microbial co-culture, namely mixed culture, are needed. This paper briefly describes the interaction mechanism between different lactic acid bacteria strains in fermented milk and the effect of mixed culture of lactic acid bacteria on the sensory and nutritional characteristics of fermented dairy products. Uncover the interaction mode and mechanism among lactic acid bacteria flora in fermented milk is conducive to improving substrate conversion rate and process performance of product, which provides a theoretical reference for lactic acid bacteria co-culture in yield regulation, product functionalization and resource utilization.

In this study, a numerical simulation is used to study the effect of initiation methods on the damage distribution on both sides of an air-spaced charge blasthole using lead azide as the explosive and polymethyl methacrylate as the experimental material. The digital image correlation system determines the evolution of the global strain field and the strain attenuation pattern of the air section, and the dynamic caustics experimental system investigates the effect of detonation methods on the dynamic fracture behavior of the precrack. The experimental results show that the damage induced on both sides of the cylindrical charge blasthole has significant fractal properties. The damage degree corresponding to each initiation point of the charge section is the smallest, and the damage degree gradually increases along the detonation path. When it approaches the noninitiating end, the damage degree reduces further due to a decrease in the energy accumulation rate and a portion of the energy dissipation. When the outer detonation method is employed, both sides of the central air section are damaged, but not when the other detonation methods are used. The effect of different initiation methods on the radial compressive strain of the air segment strain field is mostly reflected in the strain size and strain decay rate, whereas the effect on the axial tensile strain is primarily reflected dynamically and in the decay rate. The attenuation coefficient of the strain field is the greatest when the outer detonation is initiated, regardless of whether the strain is radial or axial. The fracture behavior of the precrack end varies considerably depending on the detonation method. When both the inner and outer detonations are used, the crack exhibits a typical I type generated by tensile failure. When antarafacial detonation is used, the crack initiation is mixed I–II, and the specific performance is tensile-shear destruction. The origin of the crack initiation at the end of the precrack is described using LS-DYNA numerical simulation software, and the distribution pattern of the stress field at the blasthole wall is derived. The pressure distribution along the axial hole wall of the blasthole is considerably affected by different detonation methods. The charge section is mainly reflected in the position of the pressure peak and the pressure distribution shape, whereas the air section is primarily reflected in the size of the pressure peak and the pressure distribution shape.

To investigate the effects of different packaging methods for preservation on the quality of Chinese flowering cabbages, kitchen towel (ZJ), common plastic bags (CPE), and modified atmosphere bags (EFB and JG) were used to keep them fresh, with untreated ones as the control (CK). The Chinese flowering cabbages were stored at room temperature (18～23 ℃) or low temperature (4～6 ℃) for 5 days and 25 days, respectively. Then, they were evaluated for commerciality in appearance, rotting rate, etiolation rate, weight loss, and changes in the content of chlorophyll, water, soluble sugar and vitamin C. The results showed that the fresh-keeping effect of modified atmosphere bags (EFB and JG) was better than that of CPE and CK, and ZJ exhibited the worst effect. Compared with other methods, Chinese flowering cabbages packed with EFB and JG showed higher commerciality in appearance and maintain higher nutritional quality. Among them, JG had an even better fresh-keeping effect, with a rotting rate of 0.03%, an etiolation rate of 0.42%, a weight loss of 1.55%, and a minor decrease in chlorophyll content and water content (5.01% and 1.26%, respectively) after 25 days of low temperature storage; on the other hand, when compared with day 1, there was no significant difference in the content of soluble sugar after 15 days of low temperature storage (P>0.05). In addition, the content of vitamin C only decreased by 11.43%, a value significantly lower than that of any other methods (P

Objective To evaluate the association between prophylactic plasma transfusion and postoperative bleeding rate in critically ill patients undergoing different invasive procedures. Methods The information of ICU patients who received different invasive procedures from January 2019 to December 2019 in 6 tertiary hospitals in China were retrospectively investigated. The inclusion criteria of patients were as follows: age ≥ 18 years; received invasive procedures; INR ≥ 1.5 within 72 hours before surgery. Exclusion criteria were patients with incomplete case records. The patients finally included in the study were divided into prophylactic plasma transfusion group and non-prophylactic plasma transfusion group according to their plasma transfusion status. The outcome variable was the incidence of invasive procedure-related bleeding within 48 hours after different invasive procedures. Results A total of 407 patients underwent invasive procedures, and 362 patients were finally included in this study after excluding 45 patients with incomplete case records. The proportions of prophylactic plasma transfusion in different types of invasive procedures were central venous catheterization (46/146, 31.5%), thoracentesis (13/37, 35.1%), bronchoscopy (8/31, 25.8%), tracheal intubation (9/38, 23.7%), arterial catheterization (9/50, 18.0%) and others (13/60, 21.7%). The bleeding rates showed that different invasive procedures presented no statistical difference between the groups received plasma transfusion or not. In the prophylactic plasma transfusion group, the bleeding rate of arterial catheterization (4/9, 44.4%) was the highest, but all were potential bleeding, followed by tracheal intubation (4/10, 40.0%) and central venous intubation (16/46, 34.8%), with a higher rate of significant bleeding. Conclusion Prophylactic infusion of plasma did not reduce the bleeding rate after different invasive procedures, but prospective studies are needed to further confirm the conclusion; this study also provides a certain data basis for later prospective studies.

Objective: To explore the mechanism of Guizhou Rosa roxburghii Radix in the treatment of ulcerative colitis in rats based on TLR4/NF-κB signaling pathway. Methods: The ulcerative colitis model was established by gavage with 2,4,6-trinitrobenzenesulfonic acid (TNBS)/ethanol solution, gavage with Rosa roxburghii Radix aqueous decoction high, medium and low dose groups (8, 4 and 2 g/kg) and salazosulfanil group (0.3 g/kg). Observation of the appearance, motor behaviour and blood stool of the rats. Serum and colon of rats were collected, and hematoxylin-eosin (HE) staining was used to observe the pathological changes in the colon of each group of rats. Enzyme-linked immunosorbent assay (ELISA) for the detection of serum interleukin (IL)-1β, IL-6, TNF-α levels in rats. Reverse transcription-polymerase chain reaction (RT-PCR) for the detection of rat colon Myd88, NF-κB p50, NF-κB p65, TLR4 mRNA expression. Protein immunoblotting (Western blot) was performed to detect Myd88, NF-κB p50, NF-κB p65, TLR4 protein expression in rat colon. Results: Rosa roxburghii Radix aqueous decoction significantly improved colonic inflammatory injury in rats with ulcerative colitis, especially in the high dose group of Rosa roxburghii Radix aqueous decoction. Compared with the model group, the Rosa roxburghii Radix aqueous decoction high-dose group showed significant improvement in colon pathological damage. Serum IL-1β, IL-6 and TNF-α levels were significantly decreased in the Rosa roxburghii Radix aqueous decoction high-dose group (P

A case of Trichilemmal carcinoma is reported. A 71-year-old man had undergone left lung transplantation 4 years ago. An asymptomatic light red mass in green- bean size appeared on the left temporal area 3 years ago, without any treatments. The skin lesion grew rapidly since half a year ago. Physical examination showed a reddish plaque sized about 2.5 cm×2.0 cm on the left temporal area with a slightly rough surface. Histopathology showed that the infiltrative tumor mass was involved in the sebaceous glands, sebaceous ducts, and hair follicles. Atypical cells and pathological mitosis were evident. Diagnosis: Trichilemmal carcinoma. Extensive surgical excision and rhomboplasty were performed. No recurrence was observed during follow up.

In order to maximize the total spectrum efficiency and improve the Quality of Experience (QoE) on Elastic Optical Network (EON), an adaptive modulation method based on Deep Neural Network (DNN) is proposed. Firstly, the network transmission quality in optical fiber is estimated. Then, the route length, hop number and video quality are taken as the three parameters of the request characteristics, and the deep learning method is adopted to selected the modulation system with the maximum spectrum efficiency according to the desired QoE of each requirement. The simulation results show that the average spectral efficiency of the proposed method is 51%and 32%higher in National Science Foundation (NSF) network than that of distance adaptive method and integer programming method, and 43%and 29%higher in China Network (CN) backbone network. In addition, the blocking probability of the proposed method is 0.01 lower than that of the distance adaptive method and integer programming method.

For the security problem of terminal devices accessing to the network server in internet of things（IoT），an identity authentication protocol was presented based on elliptic curve cryptography（ECC）and cookie information for internet of things terminal.Firstly，the protocol used user identity information，server private key，random number and expiration time of cookie to form a cookie file.Then，it was encrypted with ECC and stored in the smart terminal.In authentication phase，the mutual authentication was achieved by comparing the security parameters calculated by cookie information.Performance analysis shows that it can resist many kinds of attacks and provide high security，low computation and low communication cost，which was suitable for the terminal devices of limited resources in internet of things.

With the rapid development of social network, people can present or share their opinions and emotions on the micro-blog, and as a result, large amount of blog texts and emotional information of different topics are produced. As the traditional text mining algorithms cannot deal with these blog texts with fractional contents and different personal emotions effectively, this paper presents a novel weighting computation approach based on the key characters of micro-blog posts to get the dynamic interests of bloggers on different times. Furthermore, based on the emotion classification, the emotion transition tendency analysis can also be implemented. Experimental results show the feasibility of the presented approach.

Background and objective It is unclear how could endostatin effect tumor lymphangiogenesis? The aim of this study is to explore inhibitory effect of recombinant human endostatin injection (endostar) on lymphangiogenesis in non-small cell lung cancer (NSCLC) tissue and its effect on circulating tumor cells (CTC) in peripheral blood. Methods Tumor-bearing model nude mice were divided into eight groups randomly (n=7), including control group, cisplatin group, several concentration endostar groups and endostar plus cisplatin groups. Continuous administration of Endostar for two weeks, observed one week after the end of administration. Using HE staining and immunohistochemical staining to diagnose the tumor tissue and suspect metastasis lymph nodes, detected vascular endothelial growth factor (VEGF)-C, VEGF-D, VEGF receptor (VEGFR)-3 expression level and microlymphatic vessel density (MLVD) of tumor tissue. Enrichment of circulating tumor cells in peripheral blood used immunomagnetic negative selection strategy, used immunofluorescence staining to diagnose and count CTCs. Results Microlymphatic vessel density and the positive expression rate of VEGF-C, VEGF-D, VEGFR-3 in three endostar groups and three endostar plus cisplatin groups were significantly less than those in control group and cisplatin group. Microlymphatic vessel density and the positive expression rate of VEGF-C, VEGF-D, VEGFR-3 in endostar plus cisplatin group and endostar group with high endostar concentration were significantly less than those with low endostar concentration; There was a significant positive correlation between microlymphatic vessel density and the positive expression rate of VEGF-C, VEGF-D, VEGFR-3. The number of circulating tumor cells in endostar plus cisplatin groups were significantly less than that of endostar or cisplatin alone. Conclusion Endostar could inhibit tumor lymphangiogenesis and reduce tumor cells into the bloodstream through the lymphatic. Inhibitory effect concerned with drug concentrationwith a dose-dependant.

This research is to demonstrate the development and application of new material in woven Wilton carpet. Aiming at the obstinate faults in poor dimension like blister, shrinkage and dimensional change, through analysis the weaving principle, interweave construction and production crafts, we find the key cause leading to dimension faults, that is weft jute. Through the analysis of the disadvantage of weft jute in woven Wilton, we develop the specialized polypropylene weft to replace weft jute. After verification by repeated tests, the faults of poor dimension stability like blister, shrinkage and dimensional change, which thought to be the worldwide tough problem, can be fully conquered by the application of special developed polypropylene weft and the craft. [ABSTRACT FROM AUTHOR]

Background With China's aging population, the incidence of stroke is increasing year by year, and the high disability rate places a significant burden on patients, families, and society. It is extremely important to strengthen the rehabilitation self-efficacy of home-based stroke patients in order to assist them return to society as soon as feasible. Currently, less emphasis is being paid to the influence of environmental factors on rehabilitation self-efficacy in stroke. Objective To investigate the current status of rehabilitation self-efficacy of stroke patients in community, and explore the influence of different environmental factors on rehabilitation self-efficacy of stroke patients. Methods Using convenience sampling, from December 2019 to September 2020, 262 stroke patients in the subordinate communities of 4 community health service centers in Zhengzhou, Henan Province were enrolled in the survey. The Demographic Information Questionnaire was used to collect general data, the Modified Rankin Scale was used to assess the physical function of stroke patients, the Measure of Stroke Environment was used to assess the current situation of stroke environment, and the Chinese Version of Stroke Self-efficacy Questionnaire was used to assess the rehabilitation self-efficacy of stroke patients. The effects of various environmental factors on rehabilitation self-efficacy of stroke patients were investigated by hierarchical regression analysis. Results A total of 285 questionnaires were distributed, a total of 262 valid questionnaires were collected, with an effective response rate of 91.93%. The rehabilitation self-efficacy score of 262 stroke patients was (76.1±26.3). Receptivity, physical environment and communication environment accounted for 30.9% of the total variation in rehabilitation self-efficacy (P

Characteristic viscosity is a key indicator of the quality of polyester melts, whose accurate prediction can help to identify potential quality problems of polyester melts in advance, adjust the process parameters in time and reduce enterprise losses. Considering the data incompleteness, data time series and high dimensional redundancy of the polyester melt production process, a method is proposed to predict the characteristic viscosity of polyester melt under incomplete data. A missing data generative adversarial nets (MDGAN) with a convolutional neural network discriminator and an attention long short-term memory neural network generator is designed to address the data incompleteness problem caused by the extreme production environment of polyester melts, and the missing data is filled by the adversarial generation mechanism. The extreme gradient boosting-bidirectional gated recurrent unit (XGBoost-BiGRU) is designed to predict the viscosity of polyester melts based on high dimensional redundancy and temporal characteristics prediction. The actual data test results of a polyester fiber manufacturer in Zhejiang show that the filling accuracy of the MDGAN algorithm at different missing rate data sets is better than that of data filling algorithms such as KNN,RF,MICE,and GAIN. The XGBoost-BiGRU characteristic viscosity prediction method has significant advantages over STL-GPR, CAGRU, BiGRU. In combination of MDGAN characteristic viscosity prediction, the method proposed can effectively solve the problem of predicting the characteristic viscosity of polyester melts under incomplete data.

In response to the low recall rate of detection-based methods and the problem of missing target location information in density-based methods, which are the two mainstream dense-counting methods, a detection and counting method based on density map regression is proposed by combining the two tasks, achieving the counting and positioning of target objects in dense scenes. Complementing the advantages of two methods not only improves recall rate but also calibrates all targets. To extract richer feature information to deal with complex data scenarios, a feature pyramid optimization module is proposed, which vertically fuses low-level high-resolution features with top-level abstract semantic features and horizontally fuses same-size features to enrich the semantic expression of target objects. To address the issue of low pixel proportions occupied by target objects in dense counting scenarios, an attention mechanism for small targets is proposed to improve the network’s detection sensitivity, which can enhance the attention of the network to target objects by constructing a mask on the input image. Experimental results demonstrate that the proposed method significantly improves recall rate and accurately locates targets while maintaining accuracy, effectively providing counting and positioning information of input image, which has a wide range of application prospects in various fields such as industry and ecology.

For a steel factory production of 55SiCr spring steel，the reduction of area of the oil quenched and tempered treatment wire rod after processing is less than 40%， which affects the subsequent spring coiling process and the service life of the spring. The casting billet and wire rod were evaluated by methods of low-magnification pickling test， tensile test， oil quenched and tempered treatment， drill cuttings test， etc， it was found that the center segregation of the casting billet was the main cause of poor drawing performance. Through the optimization test study of continuous casting process， the results showed that high superheat had a significant effect on the segregation of billet and the drawing performance of wire rod.When the superheat was 35 ℃ compared with 18 ℃， the reduction of area and elongation increased by 2% and 0. 8% respectively. The electromagnetic stirring current of the mold was increased from 150 A to 320 A， and the center equiaxed grain rate was increased from 8%-8. 5% to 10. 5%， but the average center carbon segregation index also increased. When using the same mould electromagnetic stirring technology， reducing the electromagnetic stirring intensity at the solidified end was beneficial to improve the center segregation. When the average center carbon segregation index of the slab decreased from 1. 10 to 1. 02， the reduction of area of the oil quenched and tempered treatment wire rod increased from 39% to 47%.

With the increasing depth of roadway and the complexity of mine environment in China, the challenge of roadway bolt support will be more serious. Based on the investigation of relevant literature, the related theories of roadway bolt support were systematically summarized, and the newly proposed bolt neutral point theory, surrounding rock strength strengthening theory of bolt supporting, theory of bolt uniform strength beam support in recent years were emphatically discussed; at the same time, the action mechanism of anchor is expounded from the following four aspects: the stress distribution law of anchorage body, the load transfer law of anchor bolt, the mechanical properties of anchor anchorage interface, the rheological property of surrounding rock and its timeliness; then the main research results of bolt support form, bolt design method, bolt material and structure are introduced.Finally, combined with the research status of roadway bolt support, the problems and research priorities that need to be solved in roadway bolt support are discussed.

Graph based semi-supervised learning (GSSL) has been attracting more and more attention with its intui-tiveness and good learning performance in the machine learning community. However, it is found that existing graph based semi-supervised learning method has the problem of poor robustness and sensitivity to noise and abnor-mal data by analysis. In addition, the premise for the GSSL to have good performance is that the training data and test data are independently identically distribution (IID), which leads to some limitations in practical applications. In order to solve above problems, this paper proposes a novel clustering method based on structure risk minimization model, called a multi-model adaptation method of possibilistic clustering assumption (MA-PCA), and effectively minimizes the influence from the noise and abnormal instances based on different data distributions in some reproduced kernel Hilbert space. Its main ideas are as follows: the negative impact of noise and abnormal data on the method is reduced through fuzzy entropy; considering the effective multi-model adaptive learning of training data and test data in the same distribution and different distributions, it can also obtain good performance by rela-xing the constraint of IID between training data and test data; the algorithm implementation and convergence the-orem are given. A large number of experiments and in-depth analysis on multiple real visual datasets show that the proposed method has superior or comparable robustness and generalization performance.

Background Upper limb motor dysfunction is a common complication after stroke that seriously affects daily living skills of patients. As a common neuroelectrohysiological technique, repetitive transcranial magnetic stimulation (rTMS) has a good effect on post-stroke upper limb motor dysfunction. However, there is still no practice-based evidence on the selection of modalities of rTMS. Objective To evaluate the clinical efficacy of four rTMS modalities in post-stroke upper limb motor dysfunction by a network meta-analysis. Methods Randomized controlled trials (RCTs) about rTMS for treating upper limb motor dysfunction after stroke were searched with subject words combined with free words as searching terms in PubMed, Embase, Cochrane Library, Web of Science, CBM, CNKI, Wanfang Data, and VIP from inception to February 2022, supplemented by references from retrospective meta-analysis. Two researchers performed literature screening, data extraction, and quality evaluation separately. RevMan 5.0 and Stata 16.0 were used for statistical analysis. Results A total of 17 RCTs with 790 cases were included. Six interventions were involved: high frequency-rTMS (HF-rTMS), low frequency-rTMS (LF-rTMS), intermittent theta burst stimulation (iTBS), continuous theta burst stimulation (cTBS), sham stimulation and conventional therapy. Network meta-analysis results showed that HF-rTMS and LF-rTMS had better effects on increasing the FMA-UE score than sham stimulation and conventional therapy (PcTBS (75.3%) >HF-rTMS (71.1%) >iTBS (45.8%) >sham stimulation (20.2%) >conventional therapy (7.7%). The SUCRA ranking of decreasing the MAS score revealed the following: iTBS (77.0%) >LF-rTMS (64.1%) >cTBS (61.0%) >HF-rTMS (38.0%) >sham stimulation (30.6%) >conventional therapy (29.2%). The SUCRA ranking of increasing the MBI and BI scores showed the following: LF-rTMS (96.4%) >iTBS (74.9%) >HF-rTMS (38.6%) >sham stimulation (30.7%) >conventional therapy (9.4%). The SUCRA ranking of reducing the MEP latency showed the following: HF-rTMS (80.0%) >LF-rTMS (78.9%) >conventional therapy (58.8%) >iTBS (24.9%) >sham stimulation (7.5%) . Conclusion The available evidence indicates that, among four modalities producing better effects than sham stimulation and conventional therapy, namely LF-rTMS, HF-rTMS, iTBS, and cTBS, LF-rTMS was superior to the other three in improving upper limb motor function and daily living skills of stroke patients, iTBS performed best in decreasing upper limb muscle tension, and HF-rTMS did best in intervening the corticospinal excitability.

Manganese is one of the important strategic resources in China, and there is a saying that “no manganese, no steel”. In 2020, China’s output of electrolytic metal manganese was 1501300 tons, accounting for 96.5% of the global output. At present, manganese metal is mainly obtained using the electrodeposition process. Electrolytic manganese anode slime (EMAS) is a kind of solid waste generated during the production of electrolytic metal manganese, which contains a significant amount of manganese, lead, and other resources. Every year, 60000−180000 tons of EMAS will be discharged in China, and direct discharge will cause severe environmental pollution. Cleaning and efficiently leaching Mn from EMAS is the key to realizing its resource utilization. A large number of studies have achieved efficient leaching of manganese from EMAS. Still, there are a number of issues, such as complicated processes, high leaching cost, a large amount of reducing agent, and residual organic matter in the leaching solution. Therefore, it is urgent to find a new method for efficient clean leaching of manganese from EMAS. This study proposed a new method of enhancing manganese leaching from EMAS with an H2SO4–H2O2 leaching system. The effects of the dosage of H2SO4 and H2O2, reaction temperature, reaction time, and solid–liquid ratio on the leaching efficiency of manganese from EMAS were studied. The results show that the leaching efficiency of manganese was 97.23%, and the content of Pb in the leaching residue was 53.71%, when the mass ratio of EMAS to H2O2 was 1∶0.8, the mass ratio of EMAS to H2SO4 was 1∶0.9, the leaching temperature was 45 ℃, the solid–liquid mass ratio was 1∶10 and the leaching time was 15 min. Leaching mechanism analysis showed that manganese oxide leaching in EMAS was reduced by H2O2 under acidic conditions, and Mn mainly exists in the leaching solution as MnSO4, as well as Pb in leaching residue is mainly enriched with PbSO4. This study offers a new idea for resource utilization of EMAS.

Objective To explore the application of team-based learning(TBL) combined with case-based learning (CBL) in training program of thyroid surgery on medical intern. Methods A prospective study was conducted in 94 interns with training program from November 2020 to June 2021 in thyroid surgery, Ruijin Hospital. The interns were grouped chronologically. Forty-six interns from November 2020 to February 2021 were included into control group and 48 interns from March 2021 to June 2021 into study group. Interns in control group were given traditional training and interns in study group with TBL with CBL training. Basic theory and knowledge, basic operative skill and ability of managing crisis were evaluated and compared between two groups. Results The basic theory and knowledge in study group were significantly better than that in control group (t=12.610, P0.05) and ability of managing crisis (t=1.313, P>0.05) between two groups. As for crisis management abi-lity, the team work ability (t=3.610, P

In the electrolyte containing Nd2O3 particles with different concentrations, the micro - arc oxidation technology was used to prepare the coatings on the surface of 2A12 aluminum alloy. The effects of Nd2O3 particles with different concentrations on the hardness, thickness and adhesion strength between the micro - arc oxidation coating and the substrate were studied, which provided a theoretical basis for the preparation of the coatings with good performance on the surface of 2A12 aluminum alloy by micro - arc oxidation. In addition, scanning electron microscope (SEM), X - ray diffraction (XRD) and X - ray photoelectron spectroscopy (XPS) were used to analyze the cross section morphology and phase composition of the coatings. TT - 230 eddy current thickness tester, HVS - 1000 digital Vickers hardness tester and MFT - 4000 multi - functional material surface performance tester were used to test the coating thickness, hardness, and adhesion strength, respectively. Results showed that the coatings were mainly composed of α - Al2O3, γ - Al2O3 and SiO2 phases. With the increase of Nd2O3 particle concentration, the hardness, thickness, and adhesion strength between the coating and the substrate performed a trend of first increasing and then decreasing. Moreover, when Nd2O3 particle concentration was 0.3 g/L, the micro hardness, thickness, and adhesion strength between the coating and the substrate reached the maximum value of 576.38 HV, 8.17 μm and 16.7 N. In summary, adding Nd2O3 was an effective method to enhance the properties of 2A12 aluminum alloy micro - arc oxidation coating, and the optimal concentration was 0.3 g/L.

To accurately detect fault by in-seam seismic survey, 10 typical observation system models, belonged to 3 categories of working face interior detection, exterior detection and others, have been built generally according to location, fault strike and detection objective. Moreover, working face interior detection is divided into 7 types according to fault location, fault throw, angle between fault strike and survey line. Afterwards exploration methods, layout of shot and geophones and data interpretation methods have been described. Furthermore, taking two typical fault detection projects as examples, the survey area conditions of working face roadway layout, coal thickness, coal seam occurrence and structural development are analyzed. According to the location and occurrence of faults to be detected, the observation system design was carried out in comparison with the observation system model. The reflection method exploration was carried out in the 11160 working face of Yunding Coal Mine, and the combined penetration and reflection method exploration was carried out in the 25050 working face of Guanyintang Coal Mine. The results of data interpretation and verification show that the results are consistent with those of exploration prediction.

As one of CFETR’s candidate blankets, water cooled ceramic breeder (WCCB) blanket undertakes important nuclear-related functions such as tritium breeding, nuclear heat extraction, and neutron shielding. The reliability of neutronics design directly affects the realization of CFETR tritium self-sustaining goal. In order to verify the reliability of the neutronics design tool, i.e. MCNP and FNEDL databases, in the WCCB blanket neutronics design, the WCCB scaling-down mock up was developed to carry out the neutronics experiment in the DT neutron environment, including two layers of lithium titanate, two layers of beryllium, three layers of cooling plate, and one layer of tungsten armor. The neutronics performance of the mock up are similar with the real blanket module. The mock up neutronics experiments were carried out using DT neutron generator, the simulated value (C) and experimental value (E) of neutronics parameters represented by tritium production rate (TPR) were analyzed. For TPR validation, two independent detection technologies were used, including the Li2TiO3 pellets as off-line TPR detectors, and the developed lithium glass detectors as on-line TPR detectors. The TPR validation was complemented by evaluating the predicted neutron-induced reaction rates of the Au, Zr foils. The experiments on the mock up were analyzed by MCNP-4C code and FENDL-3.0 nuclear data libraries, and the source term for Monte Carlo simulation was built using the custom-developed model based on depth profiling of tritium in the tritide target. The analysis results show that the C/E of TPR in the axis of two lithium titanate layers is 0.97 and 1.08 respectively, while there is a large deviation between the calculated and experimental values of TPR in the edge region of the mock up. According to the experimental results from Li2TiO3 pellets, the C/E of TPR at the edge of two lithium titanate layers is 0.65 and 0.82, respectively. The TPR is obviously underestimated by simulation at the edge of lithium titanate layers, confirmed by the C/E results of 197Au(n, γ)198Au reaction rate at the edge of lithium titanate layers, which are 0.72 and 0.90, respectively. It is indicated that there are unexpected scattered neutrons in the edge region of the mock up, resulting in the higher TPR than expected. The further experiments are needed to verify the influence of the scattered neutron on the TPR at the edge region of the mock up. To investigate the TPR gap between simulation and the experimental results from lithium glass detectors, the contribution of the fast neutrons on the 6Li(n, t)4He should be further studied. Also the other suggestions are provided for further experimental research, refering to the radiation protections and nuclear measurements.

Low-alloy engineering structural steel is widely used in many fields, because of its good mechanical and processing properties. The corrosion resistance of low-alloy engineering structural steel is related not only to chemical composition but also to microstructure, inclusions, grain size, and other factors. However, at present, the direct and fast criterion for evaluating the corrosion resistance of low-alloy structural steel, i.e., the corrosion resistance index I, in the ASTM Standard and China National Standards only involves the chemical composition of low-alloy structural steel and ignores the microstructure, inclusions, and grain size. In the literature on the corrosion resistance of low-alloy structural steel, the coupled effect of chemical composition and other material factors on corrosion resistance and the quantitative analysis of each factor have not been reported. Therefore, a new corrosion resistance index for low-alloy structural steel that includes more factors needs to be proposed. Through the neutral salt spray accelerated corrosion test of eight kinds of low-alloy engineering structural steels with similar composition and microstructure produced by different manufacturers or production lines, combined with the methods of composition test, microstructure analysis, corrosion product analysis, data statistics, and calculation fitting, a composite corrosion resistance index Y for low-alloy structural steel was proposed, and a quantitative index formula containing several factors, including chemical composition, inclusions, microstructure, and grain size, was established. Results show that the corrosion resistance of low-alloy structural steel is affected by the coupling of many material factors, not only the traditional corrosion resistance index I but also inclusions, microstructure, and grain size. The degree of influence is in the order of corrosion resistance index I determined by corrosion-resistant alloy elements, total inclusions, pearlite content, and grain size. The composite corrosion resistance index can be used as an effective criterion for the corrosion resistance of low-alloy structural steel and is of significance in engineering applications.

A blockchain is a cryptographic distributed database and network transaction accounting system. In the current era of major technological changes, blockchain technology, with its cryptographic structure, peer-to-peer (P2P) network, consensus mechanism, smart contract and other mechanisms, is decentralized, tamper-proof, and traceable and has become a hot spot in the development of informatization. Classified protection is one of the basic policies of information security in China. The implementation of the information security level protection system can not only guide various industries in performing security management in accordance with the equivalent security standards, but also ensure that supervision and evaluation institutions follow the laws and regulations, which is of significance to network security. As the application of blockchain technology in various industries is becoming more extensive, it is necessary to simultaneously promote the national classified protection of blockchain security assessment, which contributes to the sustainable and healthy development of blockchains in China. According to the revised assessment methods of grade protection, in addition to the status of universality requirements, evaluation specifications should be formulated for specific technologies and fields (such as cloud computing, mobile Internet, Internet of Things, industrial control, and big data). In view of the particularity of blockchain technology, China has initiated the formulation of blockchain evaluation specifications, but has not applied the level protection standards to the formulation of blockchain evaluation specifications. Therefore, the assessment requirements and enforcement proposals are specified for the blockchain’s core technologies, such as P2P network, distributed ledger, consensus mechanism, and smart contracts, according to the application and data security layer requirements at Level 3. Moreover, the current running data of blockchains and their security audit mechanism based on the log workflow were summarized and analyzed respectively in compliance with the control points specified in classified protection 2.0. Our investigation indicates that blockchains can satisfy the requirements of evaluation items in three aspects, namely, software fault tolerance, resource control, and backup and recovery. However, further improvements are needed for other aspects, including security audit, access control, identification and authentication, and data integrity.

An enhanced algebraic fault analysis on PRESENT was proposed.Algebraic cryptanalysis was introduced to build the algebraic equations for both the target cipher and faults.The equation set of PRESENT was built reversely in order to accelerate the solving speed.An algorithm of estimating the reduced key entropy for given amount of fault injec-tions was proposed,which can evaluate the resistance of PRESENT against fault attacks under different fault models.Fi-nally,extensive glitch-based fault attacks were conducted on an 8-bit smart card PRESENT implemented on a smart card.The best results show that only one fault injection was required for the key recovery,this is the best result of fault attacks on PRESENT in terms of the data complexity.

Objective To explore the curative effect and parameter settings of vagus nerve stimulation (VNS) therapy in refractory epilepsy. Methods VNS was performed in 71 patients with drug-resistant epilepsy, and McHugh classification was used to evaluate the curative effect of VNS. Programmable pulse parameters included output current, frequency, pulse width, and On/Off times. The optimum settings for each patient should balance the goals of maximizing efficacy, minimizing side effects, and preserving battery life. Results After operation, all patients were followed up for 3-56 months (median 22 months), and experienced a significantly reduced seizure frequency compared with before operation [18 (3, 92) vs 30 (5, 145) times/month; Z = 826.500, P = 0.000]. In these patients, 20 cases (28.17% ) had < 50% reduction of seizure frequency, and 51 cases (71.83% ) had ≥ 50% reduction of seizure frequency, including 27 cases (38.03%) with ≥ 80% reduction and 14 cases (19.72%) with seizure free. Seizure termination or seizure diminution was reported in 8 patients (11.27% ) after using magnet. Conclusions VNS is a safe and effective therapy in medically refractory epilepsy. Optimized output current is generally 1.00-1.75 mA, however, 0.75 mA is also an efficient current. Besides, parameter settings should be considered to reach the maximizing efficacy. DOI: 10.3969/j.issn.1672-6731.2015.09.008

The security of LED,a lightweight block cipher proposed in CHES 2011,was evaluated by the template attack (TA).Several improvements of TA from the perspective of the preprocessing optimization was proposed.Firstly,the noise offset was calculated by using the phase-only correlation factor in the frequency view of the power trace to eliminate the data interference in the template building phase.Secondly,a novel character extracting method was proposed based on calculating the cross-cluster offset of different clusters classified by the plaintexts to cut the different leakage points from the power traces automatically.Thirdly,a dynamic effective power points choosing strategy was proposed by utilizing the mean value and the noises of the of power traces to evaluate the differences between different templates and improve the utilization of side channel information.Experiment results demonstrate that the proposed techniques of data alignment and automatically data cutting enlarge the differences of templates and reduce the number of the required power trace in both the template building and attacking phase.The proposed effective power points choosing strategy reduces the data complexity of the attack and only two power traces are required to launch the attack with the success rate of 100%.

A sparse expression of fast fading channel and its sensing method were proposed for orthogonal frequency-division multiplexing (OFDM) system of sparse pilot under the condition of imperfect carrier synchronization.First,a sparsified core vector based sparse expression of the generalized channel impulse response (G-CIR) was proposed by deriving compressed sensing model of the sparse pilot system.Then,both the sparsified core vector and G-CIR were reconstructed by orthogonal matching pursuit(OMP).Simulation results demonstrate that the proposed algorithm can effectively reduce the bit error rate (BER) of the OFDM system with imper ect carrier synchronization.

Abstract:The security of LED against the algebraic side-channel attack (ASCA)was evaluated, which is a lightweight block cipher proposed in CHES 2011.Firstly, the attack model of ASCA was analyzed, and then the design and algebraic representations of LED were described. Secondly, the power leakages of LED on ATMEGA324P microcontroller were measured by a digital oscilloscope; some leakage points with obvious power patterns were chosen as the targeted points and used to deduce the Hamming weight via computing the Pearson correlation factor; satisfiability-based, Pseu-do-Boolean optimization-based, linear programming-based methods were used to representing Hamming weights with algebraic equations. Finally, the CryptoMinisat and the SCIP solver were applied to solve for the key and many attacks are conducted under different scenarios. Experiment results demonstrate that LED is vulnerable to ASCA, full 64 bit master key can be derived via analyzing the HW leakages of the first round in LED.

A new fault analysis method on PRESENT—algebraic fault attack was proposed.This attack combined conventional algebraic cryptanalysis with fault attack,firstly built equivalent Boolean algebraic equations of cipher encryption by algebraic cryptanalysis method; secondly got information of fault cryptograph by fault attack technique,and transformed differential of fault and cryptograph into additional algebraic equations; finally utilized Crypto Mini SAT solver to solve the equations and recover key.Experiments demonstrate that after injecting 4-bit fault to the 29th round of PRESENT-80,the fault location and fault value are unknown,only 2 injectings can recover 64-bit last whitening key in 50 seconds that reduce master key of PRESENT-80 searching space to 216,then recover the master key after 1 minute brute-force-search on average; compared with previous fault attack on PRESENT,the amount of this attack sample is the smallest;meanwhile,the analysis method proposed can be applied into the algebraic fault attack of other block ciphers.

An improved boyer-moore (BM) algorithm for space protocol identification was proposed.First,a space data preprocessing technique based on bit distance was used to increase the size of data set.A decimal jumping technique was introduced to enhance the matching efficiency for the col head part of the BM algorithm.Then,the regular expression method was applied to proceed the protocol identification and the hierarchy associated analysis technique was proposed to improve the efficiency of multi-level space protocol identification.Finally,the complexity of the proposed algorithm was analyzed and verified with concrete experiments.The results show that with the proposed algorithm,as to pattern string length m,the time complexity of the single layer protocol identification can be reduced to (1+m/4)/m of the BM algorithm.The efficiency of the protocol identification for multi-level layers can be improved about 2.5 times.Meanwhile,comparing with BM algorithm,the proposed algorithm can solve the problem of pattern string shortage and large wildcards in the space data.The identification iciency in case of huge data packages can be improved and the new formed data block can restrain the state expansion for the DFA matching engine in regular expression.

Based on the principle of sign change fault attacks,an improved fault analysis method was presented against elliptic curve cryptosystems with sliding window method for point multiplication.When faults on double instruction it could effectively solve the “zero block failure” problem.Experiment results demonstrate that 15 times fault injections are enough to recover full 192bit key.When faults on add instruction,a new fault analysis method was proposed.Experiment results demonstrate one fault injection can reduce searching space 27~215.The method presented here can provide some ideas for fault attack on other cryptosystems using sliding window method.