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Background We aimed to evaluate the effect of a surgery technique-total arthroscopic internal fixation with adjustable double loop plate in treatment of patients with tibia avulsion fracture of posterior cruciate ligament (PCL). Methods From April 2018 to January 2020, 26 patients with tibia avulsion fracture of PCL treated in the joint surgery of our hospital were enrolled in this retrospective cohort study. According to the way of operation, the patients were divided into the experimental group (receiving total arthroscopic internal fixation with an adjustable double loop plate) and the control group (receiving traditional open surgery). The knee joint X-ray, CT or magnetic resonance imaging (MRI) were used to evaluate the injury or the fixation effect. Results There were no significant differences in baseline patient demographics between the two groups in terms of age, sex, the average time from injury to surgery, type of surgery, preoperative knee range of motion, Lysholm score, IKDC score and KT-1000 score (P>0.05). The average operation time in the experimental group (59.5 ± 10.6 minutes) was significantly shorter than that in the control group (96.8 ± 13.7 minutes) (P < 0.05). Postoperative re-examination of knee CT and X-ray showed that the fracture fragments were well fixed in all patients. The fracture was all healed 2 months after the operation. Post-operative posterior drawer tests were negative in all patients at final follow-up. All patients regained a satisfactory knee range of motion and the flexion and extension function and were satisfied with the results of surgery and rehabilitation. There was significant difference (P < 0.05) in the Lysholm scores, the IKDC scores, the KT1000 scores, and the ROM between preoperative and postoperative values in the control group and the experimental group. However, there were no significant differences in these values between the two groups (p>0.05).Conclusions Total arthroscopic internal fixation with adjustable double loop plate is relatively simple, safe, minimally invasive, and reliable. After taking this operation and rehabilitation training, patients with tibia avulsion fracture of PCL can regain a satisfactory knee range of motion and the flexion and extension function.

Purpose: To develop an accelerated postprocessing pipeline for reproducible and efficient assessment of white matter lesions using quantitative magnetic resonance fingerprinting (MRF) and deep learning. Methods: MRF using echo-planar imaging (EPI) scans with varying repetition and echo times were acquired for whole brain quantification of (Formula presented.) and (Formula presented.) in 50 subjects with multiple sclerosis (MS) and 10 healthy volunteers along 2 centers. MRF (Formula presented.) and (Formula presented.) parametric maps were distortion corrected and denoised. A CNN was trained to reconstruct the (Formula presented.) and (Formula presented.) parametric maps, and the WM and GM probability maps. Results: Deep learning-based postprocessing reduced reconstruction and image processing times from hours to a few seconds while maintaining high accuracy, reliability, and precision. Mean absolute error performed the best for (Formula presented.) (deviations 5.6%) and the logarithmic hyperbolic cosinus loss the best for (Formula presented.) (deviations 6.0%). Conclusions: MRF is a fast and robust tool for quantitative (Formula presented.) and (Formula presented.) mapping. Its long reconstruction and several postprocessing steps can be facilitated and accelerated using deep learning.

As the coal mining depth increases year by year, the deformation and failure of deep roadway become more serious. Therefore, new support equipment with high supporting force and yieldable character is quite necessary for mining safety. In this research, a new mechanical yielding steel prop (MYSP) with high stable load capacity was introduced, which features sustaining large deformation in the field. The test shows that the load capacity provided by doublelayer steel balls is greater than that of single-layer steel balls, and that provided by high-hardness steel balls is higher than that of low-hardness steel balls. When double-layer high-hardness steel balls are adopted, the load capacity firstly increases and then remains stable with the increase of displacement, while it firstly increases and then decreases and finally remains stable with the increase of displacement when double-layer low-hardness steel balls are adopted. The load capacity decreases with the increase of inclined angle of the outer tube, but the influence of the inclined angle of the outer tube on load capacity provided by high-hardness steel balls is small. The load capacity increases gradually with the yielding strength of the prop. Therefore, the MYSP with different load capacities can be designed by changing the yielding strength of the outer tube and inner tube. The field application shows that the MYSP has good characteristics of yielding and high constant resistance. It is very effective for controlling the deformation of surrounding rock mass using the MYSP for roadway pre-support, which also reduces the supporting cost significantly.

Scanning electron microscopy (SEM) micro-morphology analysis, X-ray diffraction (XRD) and energy-dispersive X-ray diffraction (EDX) component analysis were conducted on the fouling of continuous emission monitoring system (CEMS) sampling tube at the outlet of limestone-gypsum wet flue gas desulfurization (WFGD) of unit 1 in a 600 MW supercritical coal-fired power plant in Inner Mongolia Autonomous Region. The results show that the main component of fouling was ammonium dihydrogen phosphate, which was generated by the reaction between phosphoric acid in the phosphoric acid titration device and the NH3 escaping from the selective catalyst reduction (SCR) denitrification system, and corresponding treatment measures were taken. It indicates that the average value of ammonia escape was reduced from 1.79 ppm to 1.54 ppm through the ammonia injection optimization test of the SCR denitrification system (at the load of 410 MW of the unit), which effectively reduced the generation of fouling. This research provides reference for improving the reliability of coal-fired unit operation after ultra-low emission transformation.

The Internet of Things (IoT), recognized as one of the major technological revolutions in the century, is deployed and used today sociality. The related security issues are taken into account by the academia and industry. Recently, an online/offline certificateless signature scheme (OO-CLS) proposed by Saeed et al. is used to construct a heterogeneous remote anonymous authentication protocol (HRAAP) in wireless body area networks based on the IoT. However, in this article, we show that the scheme is vulnerable to the forgery attack which is not necessary to know any information except public system parameters. Furthermore, we show that the sensor node can generate the partial private keys and secret values of other sensor nodes after it obtains its partial private key. This causes that the HRAAP is also insecure. Finally, we improve the OO-CLS and analyze the security of our improved scheme.

Wireless sensor networks have attracted much attention recently due to their various applications in many fields [...]

Recent research has demonstrated that landscape design intensity impacts individuals’ landscape preferences, which may influence their eye movement. Due to the close relationship between restorativeness and landscape preference, we further explore the relationships between design intensity, preference, restorativeness and eye movements. Specifically, using manipulated images as stimuli for 200 students as participants, the effect of urban green space (UGS) design intensity on landscapes’ preference, restorativeness, and eye movement was examined. The results demonstrate that landscape design intensity could contribute to preference and restorativeness and that there is a significant positive relationship between design intensity and eye-tracking metrics, including dwell time percent, fixation percent, fixation count, and visited ranking. Additionally, preference was positively related to restorativeness, dwell time percent, fixation percent, and fixation count, and there is a significant positive relationship between restorativeness and fixation percent. We obtained the most feasible regression equations between design intensity and preference, restorativeness, and eye movement. These results provide a set of guidelines for improving UGS design to achieve its greatest restorative potential and shed new light on the use of eye-tracking technology in landscape perception studies.

At present, natural orifice specimen extraction surgery (NOSES) has attracted more and more attention worldwide, because of its great advantages including minimal cutaneous trauma and post-operative pain, fast post-operative recovery, short hospital stay, and positive psychological impact. However, NOSES for the treatment of gastric cancer (GC) is still in its infancy, and there is great potential to improve its theoretical system and clinical practice. Especially, several key points including oncological outcomes, bacteriological concerns, indication selection, and standardized surgical procedures are raised with this innovative technique. Therefore, it is necessary to achieve an international consensus to regulate the implementation of GC-NOSES, which is of great significance for healthy and orderly development of NOSES worldwide.

DevOps is a combination of collaborative and multidisciplinary efforts of an organization to control continuous delivery and updates of new software while guaranteeing their reliability and correctness. In the software industry, the implementation of DevOps (development and operations units) faces many challenges that are specifically associated with the security. The objective of this study is to identify and develop a prioritization based taxonomy of DevOps security challenges. The total of eighteen DevOps security challenges were extracted using systematic literature review approach and were further evaluated with experts using questionnaire survey study. Finally, the multi criteria decision making PROMETHEE-II approach was used to prioritize and develop the taxonomy of identified factors and their categories. The implications of PROMETHEE-II approach are novel in this research domain as it has been used successfully in various other domains e.g. medical, banking, internet techniques and management etc. The contribution of this study is not limited to develop the taxonomy based structure of DevOps security challenges, but also the proper prioritization of these challenges by introducing PROMETHEE-II approach in the research field of DevOps. The study results will assist the practitioners to remove the uncertainty and vagueness in the opinion of DevOps experts to secure DevOps implementation for better and continuous software development process.

The development of wireless charging technology has made research in rechargeable wireless sensing networks (WRSNs) a hot topic. Charge scheduling, which involves allocating mobile charger(s) to replenish energy to the sensors of a network so that the network can remain active for a longer time, is one of the most essential issues in this field. Most previous works addressed the charge-scheduling problem by using proactive or on-demand methods, each with its own advantages and issues. In this work, we propose a novel bottleneck prediction and removal mechanism (BP&R) that seamlessly integrates the two completely different scheduling strategies. The BP&R predicts proactively the potential charging needs that may overwhelm the on-demanding scheduling and eliminate those incidents beforehand. This allows the on-demand scheduling, which usually relies on time and/or distance factors in determining charging order, to concentrate on tackling the problem considering only the distance factor. A simple distance-based near job first (NJF) algorithm is thus sufficient for charge scheduling when time-related factors are considered prior to the determination of the charging order. Use of NJF algorithm also allow us derive a shorter path length in charge scheduling, which results in a tighter charging threshold. A lower charging threshold corresponds to fewer charging requests and less pressure on charge scheduling. In general, the new scheduling strategy relies on the on-demand feature to gather the charging demands of the network, while proactively includes additional sensor nodes that could potentially cause subsequent issues in the scheduling plan. The on-demand and proactive natures of the proposed strategy ensure that it can adapt to the dynamic charging needs of sensors, while at the same time taking precautionary measures to avoid possible burst requests in the future. Extensive simulations show that the proposed strategy can achieve a better network lifetime than other state-of-art scheduling methods.

With the continuous development of authentication approaches, password-based authentication is still the first choice for various online services today. The security of password-based authentication relies heavily on the strength of the passwords created by users. Password enhancement is a general way to increase the difficulty of cracking a password. An ideal password enhancement strategy should take into account both the usability (mainly the memorability) and the security of passwords. However, it has been found that the higher the password strength, the lower the usability of the password, and vice versa. In order to balance the usability and the security of the password, we propose a password enhancement method based on semantic transformation, which can effectively analyze the semantic structure of a given password. This enhances the password's strength through one or more password semantic transformations to make the password better protected against guessing attacks. Finally, we use publicly available real-world password data sets leaked in previous security incidents to conduct experiments. Our password enhancement strategy significantly reduces the proportion of guesses by a classic password guessing attack, which demonstrates the effectiveness of the method.

Outsourcing computing is an application of cloud computing. It is an important method to solve the problem of client resource limitation. However, outsourcing computing brings security and efficiency challenges. Matrix multiplication computation (MMC) outsourcing has attracted many researchers to carry out research and has achieved many admirable results. Unfortunately, there is still a problem with zero elements of information protection for MMC outsourcing. In this paper, we are motivated to design a protocol, which can protect the private information of the zero elements, for outsourcing MMC to the cloud server. Our proposed protocol not only solves the problem of protecting zero elements information but also has no large client-overhead. The main idea is to add a special matrix to the original matrix for hiding zero elements before transforming the computation task. Then, the cloud server computes the received encryption task and returns the result to the client. Finally, the client decrypts and verifies the result. The experiment verifies the efficiency and practicability of our protocol. The comparison with previous schemes shows that the protocol improves security without much client overhead.

The beam forming network is a key component of the realization and difference function of the single-pulse antenna array. Obtaining the amplitude and phase information of each port of the network is the premise of designing the beam forming network. This paper gives and calculates the feed phase expression of the generated and beam in the 8-element sequential rotating circularly polarized antenna array. The circular polarization components and axial ratio characteristics of the φ=0°, φ=45° and φ=90° planes are calculated by left-hand and port feeding. The results show that the pure circularly polarized wave is obtained in the direction of θ=0° when the φ=0° surface is left-handed and the port is fed. The circular polarization of the antenna is good when the angle is smaller than θ=0°. It shows that the antenna unit obtains a circularly polarized wave after adopting the sequential rotation technique; the circular polarization characteristic on the φ=45° plane and the φ=90° plane is consistent with the φ=0° plane.

The rapid development of wireless power transfer technology brings forth innovative vehicle energy solutions and breakthroughs utilizing wireless sensor networks (WSNs). In most existing schemes, wireless rechargeable sensor networks (WRSNs) are generally equipped with one or more wireless charging vehicles (vehicles) to serve sensor nodes (SNs). These schemes solve the energy issue to some extent; however, due to off-road and speed limitations of vehicles, some SNs still cannot be charged in time, negatively affecting the lifetime of the networks. Our work proposes a new WRSN model equipped with one wireless charging drone (drone) with a constrained flight distance coupled with several wireless charging pads (pads) deployed to charge the drone when it cannot reach the subsequent stop. Our model solves this charging issues effectively and overcomes energy capacity limitations of the drone. Thus, a wireless charging pad deployment problem is formulated, which aims to apply the minimum number of pads so that at least one feasible routing path can be established for the drone to reach every SN in a given WRSN. Four feasible heuristics, three based on graph theory and one on geometry, are proposed for this problem. In addition, a novel drone scheduling algorithm, the shortest multi-hop path algorithm, is developed for the drone to serve charging requests with the assistance of pads. We examine the proposed schemes through extensive simulations. The results compare and demonstrate the effectiveness of the proposed schemes in terms of network density, region size and maximum flight distance.

A $4\times4$ high-gain substrate integrated cavity (SIC) antenna array using multilayered low-temperature cofired ceramic (LTCC) technology is proposed and designed for $W$ -band applications. The TM211 mode of the SIC is utilized. Two parasitic patches are introduced on the top surface of the SIC to adjust the aperture electromagnetic field distribution of the TM211 mode in the cavity for obtaining a high-gain broadside radiation pattern. A bow tie shape is adopted for the parasitic patches to improve the matching characteristic of the SIC. The SIC is modified to a stepped flared shape to improve the gain characteristic of the antenna element. Subsequently, a two-layer low-loss substrate integrated waveguide (SIW) feeding network is designed for the $4\times4$ antenna array on the basis of the proposed high-gain SIC radiating element. The proposed antenna array shows a wide measured bandwidth of 17.48% from 81.45 to 97.05 GHz at $\vert \textrm {S}_{11} \vert dB and a measured gain of up to 20.3 dBi.

OBJECTIVE A large-scale multicenter retrospective cohort study was conducted to compare the short- and long-term outcomes of robotic gastrectomy (RG) and laparoscopic gastrectomy (LG) for gastric cancer. SUMMARY OF BACKGROUND DATA RG is being increasingly used worldwide, but data from large-scale multicenter studies on the short- and long-term oncologic outcomes of RG versus LG are limited. The potential benefits of RG compared with LG for gastric cancer remain controversial. METHODS Data from eligible patients who underwent RG or LG for gastric cancer of 11 experienced surgeons from 7 centers in China between March 2010 and October 2019 were collected. The RG group was matched 1:1 with the LG group by using propensity score matching (PSM). The primary outcome was postoperative complications. RESULTS After PSM, a well-balanced cohort of 3552 patients was included for further analysis. The occurrence of overall complications (12.6% vs 15.2%, P = 0.023) was lower in the RG group than in the LG group. RG was associated with less blood loss (126.8 vs 142.5 mL, P < 0.001) and more retrieved lymph nodes in total (32.5 vs 30.7, P < 0.001) and in suprapancreatic areas (13.3 vs 11.6, P < 0.001). The long-term oncological outcomes were comparable between the two groups. CONCLUSIONS The results of this multicenter study demonstrate that RG is a safe and effective treatment for gastric cancer when performed by experienced surgeons, although longer operation time and higher costs are still concerns about RG. This study provides evidence suggesting that RG may represent an alternative surgical treatment to LG.

Background: Long-term clinical practice has found that there are still some deficiencies in freehand joint loosening. Due to the therapist's lack of anatomical knowledge and treatment experience, and incorrect wrist joints, wrist and other parts of the force during the treatment, the incidence of wrist and lower back pain produced by the therapist has significantly increased. The purpose of the feasibility study is to observe the effects of spinal mobilization apparatus combined with sling exercise training on pain and muscle fatigue in patients with non-specific low back pain.Methods: This pilot study will recruit 82 eligible patients with non-specific lower back pain from Ningbo Rehabilitation Hospital. Patients who are re-elected to this study will be randomly assigned to the intervention group in a 1:1 ratio to receive spinal mobilization apparatus and sling exercise training on top of completing conventional rehabilitation therapy, while the control group will receive sling exercise training on top of conventional rehabilitation therapy. Primary and secondary indicators were tested at the 0-week, 8-week and 3-month follow-up phases, respectively. The Japanese Orthopaedic Association (JOA) scale was used for the primary observation and the visual analogue scale (VAS) score, core group endurance test (CET) for the secondary indicators, intra-abdominal pressure (IAP), surface electromyographic (SMEG) measurement of core muscle fatigue, musculoskeletal ultrasound measurement of diaphragm thickness (DT), range of motion (ROM) and the activity of daily life (ADL).Discussion: This pilot study will determine the feasibility of conducting a full randomized controlled trial protocol to assess the effectiveness of spinal mobilization apparatus combined with sling exercise training compared to sling exercise training alone in improving low back pain and muscle fatigue in patients with non-specific lower back pain, providing preliminary clinical evidence of the efficacy of the combined therapy in improving low back pain and muscle fatigue in patients with non-specific lower back pain.Trial registration: This trial was first registered on Chinese Clinical Trial Register, ChiCTR2100042333 on 19 January 2021.

As natural backwater structures, landslide dams both threaten downstream human settlement or infrastructure and contain abundant hydro-energy and tourism resources, so research on their development feasibility is of great significance for permanently remedying them and effectively turning disasters into benefits. Through an analysis of the factors influencing landslide dam development and utilization, an index system (consisting of target, rule, and index layers) for evaluating development feasibility was constructed in this paper. Considering uncertainty and randomness in development feasibility evaluation, a cloud model-improved evaluation method was proposed to determine membership and score clouds based on the uncertainty reasoning of cloud model, and a cloud model-improved analytic hierarchy process (AHP-Cloud Model) was introduced to obtain weights. Final evaluation results were obtained using a hierarchical weighted summary. The improved method was applied to evaluate the Hongshiyan and Tangjiashan landslide dams and the results were compared with the maximum membership principle results. The results showed that the cloud model depicted the fuzziness and uncertainty in the evaluation process. The improved method proposed in this paper overcame the loss of fuzziness in the maximum membership principle evaluation results, and was capable of more directly presenting evaluation results. The development feasibility of the Hongshiyan landslide dam was relatively high, while that of the Tangjiashan landslide dam was relatively low. As suggested by these results, the evaluation model proposed in this paper has great significance for preparing a long-term management scheme for landslide dams.

No epidemiologic studies have been conducted to assess the association of intake of dietary vitamin K with the risk of pancreatic cancer. We used prospective data from the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial between 1993 and 2009 to fill this gap. A total of 101,695 subjects were identified. Dietary intakes of phylloquinone (vitamin K1), menaquinones (vitamin K2), and dihydrophylloquinone (dihydrovitamin K1) were assessed using a food frequency questionnaire. Cox regression was applied to calculate hazard ratios and 95% confidence intervals. During a mean follow-up of 8.86 years (900,744.57 person-years), 361 cases of pancreatic cancer were documented. In the fully adjusted model, dietary intakes of phylloquinone (for quartile 4 vs. quartile 1, hazard ratio (HR) = 0.57, 95% confidence interval (CI): 0.39, 0.83; P for trend = 0.002) and dihydrophylloquinone (for quartile 4 vs. quartile 1, HR = 0.59; 95% CI: 0.41, 0.85; P for trend = 0.006), but not menaquinones (for quartile 4 vs. quartile 1, HR = 0.93; 95% CI: 0.65, 1.33; P for trend = 0.816), were found to be inversely associated with the risk of pancreatic cancer in a nonlinear dose–response manner (all P values for nonlinearity

This article is mainly aimed at defining and verifying whether the project involves environmentally sensitive areas in the process of environmental intelligent survey, calculating the position coordinate information of the target GPS position in the aerial image map under the condition of Gaussian projection, and further calculating the four corners of the image and the position of other target points under the WGS84 coordinate system. First of all, based on the POS data information of aerial equipment, this paper calculates the corresponding Gaussian projection and POS data information, then the pseudo-position information of image center coordinates is further calculated; Second, Based on the coordinates information of gauss projection, this paper calculates the heading open angle and side open angle of the camera, then calculate the width and height of the image for pose correction, and finally get the coordinate position of the corrected image center point. Finally, the GPS positions of other target points can be calculated by pixel coordinates of images, and the calculated results are pasted on Google earth for precision comparison. Experimental results show that the proposed method can accurately calculate the GPS positions of targets in aerial images.

Optical fiber ultrasonic sensor based on Fabry-Perot cavity and micro-electromechanical-system diaphragm was proven to be suitable for partial discharge detection, which shows frequency responses up to 500kHz and minimum detectable pressure as low as 0.455μPaHz−1/2.

Background Venous thromboembolism (VTE) concomitant to acute limb ischemia (ALI) is rarely reported. The purposes of the study were to investigate characteristics and identify clinical indicators of VTE in patients with ALI. Methods Electronic medical record was used to identify patients diagnosed with ALI from January 2013 to June 2019. Eligible patients were categorized as VTE or non-VTE based on the presence or absence of concomitant VTE. Univariate analysis and multivariate analysis for indicators of VTE were performed. Results A total of 153 patients with 161 ischemic limbs were enrolled. Venous duplex ultrasound (DUS) for 149 patients (157 ischemic limbs) revealed deep vein thrombosis (DVT) in 38 (24.2%) ischemic limbs of 37 (24.8%) patients. Five femoral DVTs were found intraoperatively. Six patients had pulmonary embolism (PE) and three of them died. In all, 43 (28.1%) ALI patients were diagnosed with VTE. They were treated with trans-arterial catheter-directed thrombolysis (n=22), embolectomy (n=9), primary amputation (n=4) and anticoagulation alone (n=8). The univariate analysis indicated that symptoms ≥ 2 days [odds ratio (OR): 3.42, 95%CI:1.54-7.62], Rutherford classification Ⅱb-Ⅲ (OR: 9.17, 95%CI: 2.10-40.12), leg swelling (OR: 4.44, 95%CI: 2.07-9.53), neutrophil ratio ≥ 0.80 (OR: 3.92, 95%CI: 1.72-8.93) and positive D-dimer (OR: 8.44, 95%CI: 3.65-19.53) were indicators of VTE concomitant to ALI. In the multivariate analysis, leg swelling and positive D-dimer appeared to be independent indicators. Conclusions VTE commonly occurs to ALI. Venous DUS for DVT screening should be considered for ALI patients who present one or more of these indicators.

Using the energy storage system to regulate the distribution network voltage can effectively deal with the distribution network voltage level caused by the high intermittence of renewable energies and the fluctuation of load demand. In this paper, the charging and discharging action of energy storage system is modeled as a Markov decision-making process, and a deep-Q-network based (DQN-based) voltage regulation algorithm is proposed for the distribution network with energy storage system. Since the state space of the problem is too large, this DQN-based voltage regulation algorithm uses a neural network to approach the optimal action values of the energy storage, and the neural network is trained by the experience replay strategy. The input of the neural network is the state eigenvector composed of the state of capacity (SOC) of the energy storages, the predicted power outputs of renewable energies and the power load level, and the output of the neural network is the optimal discrete charging and discharging action value used to improve the voltage level. Compared to the traditional voltage regulation methods, the proposed DQN-based voltage regulation method is a learning-based approach, which does not need the explicit uncertainty model and decreases the solution complexity. The proposed DQN-based voltage regulation algorithm is tested in the IEEE 33-bus distribution network and the results are analyzed to prove the effectiveness of the proposed voltage regulation algorithm.

The bullet subtitle reflects a kind of instant feedback from the user to the current video. It is generally short but contains rich sentiment. However, the bullet subtitle has its own unique characteristics, and the effect of applying existing sentiment classification methods to the bullet subtitle sentiment classification problem is not ideal. First, since bullet subtitles usually contain a large number of buzzwords, existing sentiment lexicons are not applicable, we propose Chinese Bullet Subtitle Sentiment Lexicon on the basis of existing sentiment lexicons. Second, considering that some traditional affective computing methods only consider the text information and ignore the information of other dimensions, we construct a bullet subtitle affective computing method by combining the information of other dimensions of the bullet subtitle. Finally, aiming at the problem that existing classification algorithms ignore the importance of sentiment words in short texts, we propose a sentiment classification method based on affective computing and ensemble learning. Our experiment results show that the proposed method has higher accuracy and better practical application effect.

This article proposes hypotheses about the relationship between innovation of management incentive mechanism and corporate performance of listed agricultural companies under “large-scale agriculture”. It selects 238 A-share listed agricultural companies on the Shanghai and Shenzhen markets from 2013 to 2018 as the research objects, and uses multiple linear regression model to perform regression analysis on panel data. The results show that management compensation and management equity incentive are positively correlated with the performance of listed agricultural companies at a 1% significance level. It is concluded that innovation of management incentive mechanism can promote the performance of listed agricultural companies, and the incentive effect of state-owned enterprises is less than that of other enterprises.

To study the effect of compound Da-Cheng-Qi Decoction (CDCQD) on the treatment of malignant bowel obstruction (MBO) with transnasal ileus tube (TIT).We observed 30 cases of MBO from July 2018 to August 2019. The patients were divided into the control group (n = 15) and the CDCQD group (n = 15) according to a random number table. All patients were inserted the TIT after admission. Twenty-four hours later, the CDCQD group began to take 100 ml CDCQD twice a day for 7 days. The control group took the plain boiled water instead. Other treatment was the same in the two groups. The waistline reduction, the release time of abdominal pain and distention, recovery of exhaust and defecation time, drainage volume of TIT were observed and compared between the two groups.Three days after insertion of TIT, the abdominal plain film was re-examined in the two groups. Most of the patients' gas-liquid level disappeared and there was no significant difference between the two groups (P 0.05). The effective rate of CDCQD group (86.7%) was significantly higher than that of control group (53.3%). The recovery time of exhaust and defecation in the CDCQD group was earlier than that in the control group (P 0.05). The daily drainage volume of TIT in the CDCQD group was less than that in the control group, especially from the fourth day to the sixth day after insertion of TIT, with a significant difference (P 0.05).TIT is an effective treatment for patients with MBO. With the basis of TIT treatment, CDCQD therapy can improve the curative effect of MBO. It can promote intestinal exhaust and defecation and improves the curative effect of palliative treatment of MBO. It is an effective method to assist Tit in the treatment for MBO patients.

DevOps is a new software engineering paradigm adopted by various software organizations to develop the quality software within time and budget. The implementation of DevOps practices is cr...

Background Recent studies have suggested that statins may be associated with a lower risk of recurrent venous thromboembolism (VTE). Methods We systematically searched PubMed, Web of Science and Cochrane Library from inception until May 2020 to identify any eligible studies that reported the association between statin use and the risk of recurrent VTE, and conducted a comprehensive systematic review and meta-analysis (PROSPERO registration number: CRD42020190169) on this matter. Results A total of 14 observational studies were included for qualitative review and 12 of them qualified for meta-analyses. The main meta-analysis found that statin use was associated with a lower risk of disease recurrence among patients with VTE (pooled adjusted HR: 0.76, 95% CI: 0.69−0.83), which was robust in sensitivity analyses and free of significant publication bias. Additionally, such association was present when restricting to periods after anticoagulation withdrawal (pooled adjusted HR: 0.78, 95% CI: 0.70−0.88) and when separately analyzing recurrent deep vein thrombosis (pooled adjusted HR: 0.71, 95% CI: 0.62−0.81) and recurrent pulmonary embolism (pooled adjusted HR: 0.80, 95% CI: 0.66−0.97; P = 0.027). Furthermore, statin use in patients with VTE was also found to be associated with a lower risk of all-cause mortality (adjusted HR: 0.65, 95% CI: 0.56−0.77), and possibly an even lower risk of bleeding (adjusted HR: 0.88, 95% CI: 0.73–1.07), albeit not statistically significant. Conclusion Statins have the potential to reduce recurrent events among patient with VTE. Randomized clinical trials to better explore the effect of statins in secondary prevention of VTE are warranted.

Nowadays, Internet platforms such as Weibo have marked a new era for the public to express their attitudes, opinions and sentiments on the government's policies or various social phenomena. The analysis of those ideas and sentiments can provide practical significance to promote the governance of cyberspace, it is also very helpful to observe and warn cyber events. Taking Sina Weibo as the object, most of the research ignores the combination of sentiment prior knowledge and user information. Therefore, the accuracy of sentiment classification is affected. In order to make full use of the rich information on social networks, the two channels text convolution neural network (TC-TextCNN), which combines multi-feature, is proposed. By improving the algorithm of the word embedding, the part of sentiment information is enhanced by sentiment dictionary. To supplement traditional features, this model construct user features according to attributes and behaviors of users. TC-TextCNN can learn semantic features, sentiment features and user features at the same time. The effectiveness of sentiment word embedding and user features has been proved by experiments. Experiments proved that this method achieves better results on classifying sentiment. And the difference of sentiment distribution under different cyber events is verified by empirical analysis, which provides a reference for the early warning of cyber events.

In practical, it is a challenge to design an antenna with circular polarization and omnidirectional patterns simultaneously. For convenient design, four detail methods for circularly polarization omnidirectional antenna are summarized and analyzed referencing the reported theses and papers. The summarized method can provide a direct guideline for researchers and engineers, which is useful for design efficiency improvement.

The left and right hand transmission lines have dual/multiple frequency characteristics, wideband phase shifting characteristics, miniaturization characteristics, and zero/negative order resonance characteristics, and the antenna array can be realized based on these characteristics of the right and left hand transmission lines. Here, the application of the left and right hand transmission lines in the antenna array is summarized.

Multinomial logistic regression (MLR) has been widely used in the field of face recognition, text classification, and so on. However, the standard multinomial logistic regression has not yet stressed the problem of data redundancy. That is to say, in multi-class classification, there are many similar features among different classes, which will cause the corresponding classes not being correctly classified. As data redundancy is a common phenomenon in many fields, in response to this phenomenon, this paper proposes a maximal uncorrelated MLR (MUMLR) classification model to solve the problem of data redundancy in multi-class classification. The main idea is to reduce the weight of similar features and try to keep more discriminative information in the data by adding an uncorrelated regularization. In addition, we use the Cauchy-Buniakowsky-Schwarz inequation to scale the original objective function into the convex function and solve it by the Adam optimization method. Its main advantages are as follows: for data with more redundant information, the classification effect of the proposed algorithm is better than the state-of-the-art algorithms. In addition, we prove that the regularization we proposed can also be applied to neural networks and has achieved good results.

The power splitter is an important device for applications such as microwave signal separation and array antenna feeding. After the emergence of the right and left hand transmission lines, most of the miniaturized power splitters are designed by utilizing the miniaturization characteristics of the left and right hand transmission lines. This paper summarizes the application of left and right hand transmission lines in the power splitter, and analyzes the advantages and disadvantages of different implementation methods.

DevOps is a new software engineering paradigm adopted by various software organizations to develop an environment of continuous deployment and delivery within time. Numerous experts are offering their services to help organizations, how to implement DevOps activities in software organization. Though, still there are various issues for software organizations to adopt DevOps activities. To overcome such issues, there must be an approach that could assist software organizations towards better adoption of DevOps activities. The core objective of this research is to design a Readiness Model for DevOps (RMDevOps) to improve the adoption of DevOps activities in a software organization. Based on existing models in other fields of software engineering, we will develop this model. We have conducted a systematic literature review and empirical study on DevOps, for understanding the impact of the success factors of DevOps in the real world and literature. This study covers the first step of development of RMDevOps model, by identifying the success factors of DevOps and presenting the outcomes in the form of robust framework.

Security in DevOps is a challenging feature because traditional existing methods of security are not fulfilling the exact requirements of DevOps. To make DevOps activities successful for organizations this study will help to identify concerns about DevOps security in real world by interviewing the practitioners having DevOps working experience. The Classical grounded theory approach has been used to build our theory. We interviewed 13 practitioners working across five companies from different regions. We contributed to identify security concerns in DevOps and try to present a theoretical model to improve understanding and guidance of DevOps adoption. The security concerns were marked as functional and nonfunctional based upon the interviews concepts to help practitioners having understanding about particular concerns. Therefore, this theory will highlight security concerns that are hindering the adoption of DevOps successfully.

Aerospace embedded software is very complex, large-scale and highly reliable, so it is very important to measure the reliability of aerospace embedded software. Based on the analysis of the characteristics of aerospace embedded software, the reliability evaluation of aerospace embedded software based on the Delayed S-Shaped model is carried out. The data set similar to the characteristics of aerospace embedded software is selected to verify the predictive ability of the model. The experimental results show that the aerospace embedded software reliability measurement model can obtain a good fitting effect.

A novel SiC double-trench MOSFET (DT-MOS) with source-recessed structure is proposed and investigated via Sentaurus TCAD simulations in this paper. The lateral resistance area beneath the source region is completely eliminated, thus suppressing the turn-on of the parasitic npn transistor effectively. As a result, the short-circuit withstanding time, the single pulse avalanche energy (E av) under unclamped inductive switching test and the threshold voltage for single-event burnout are improved by 28%, 14% and 67%, respectively, when compared to the traditional state-of-the-art SiC DT-MOS, indicating its great potential for harsh environment applications.

A new phase retrieval technique in digital holographic microscopy (DHM) with three defocused holograms is proposed. Given the defocusing distance, the phase distributions of tested specimen can be reconstructed with a simple algebraic equation. We have deduced this equation in detail. To avoid the manual operation, the defocused holograms can be flexibly and precisely obtained by introducing an electronically tunable lens based 4f system. This method is suitable for an on-axis hologram as well as the off-axis one but avoids the requirements for not only the iterative process, complex spectrum selection in off-axis DHM or additional phase-shifting devices in on-axis DHM but also the assumption of tested specimen or previous knowledge of the system. A series of simulations and the experimental results of the microlens array and water drop demonstrate the feasibility and effectiveness of the proposed method.

Background Previous observational studies regarding the prognostic value of statin on colorectal cancer (CRC) patients showed various results. Methods Articles regarding the prognostic value of statin on CRC and published in English and before October 2020 were searched in the following databases: PubMed, Web of Science, EMBASE, Medline and Google Scholar. The multivariate hazard ratios (HRs) and their 95% confidence intervals (CI) were computed to explore associations between statins use and overall mortality or cancer-specific mortality of CRC. Results The study included 5 retrospective case-control studies (including 475 statins users and 1925 no-statin users) and 11 prospective cohort studies (including 40659 statins users and 344459 no-statin users). The present study showed that statins use might be significantly associated with lower overall mortality in CRC with a random effects model (HR = 0.81, 95% CI 0.76 to 0.86, I2 = 61.9%, p value for Q test Conclusions In conclusion, the present study indicated that that statin use was a protective factor for CRC prognosis. However, the relationship between statins use and CRC prognosis requires repeated and large prospective studies to be verified.

AIM To introduce a two-step method for creating a gastric tube during laparoscopic-thoracoscopic Ivor-Lewis esophagectomy and assess its clinical application. METHODS One hundred and twenty-two patients with middle or lower esophageal cancer who underwent laparoscopic-thoracoscopic Ivor-Lewis esophagectomy at Liaoning Cancer Hospital and Institute from March 2014 to March 2016 were included in this study, and divided into two groups based on the procedure used for creating a gastric tube. One group used a two-step method for creating a gastric tube, and the other group used the conventional method. The two groups were compared regarding the operating time, surgical complications, and number of stapler cartridges used. RESULTS The mean operating time was significantly shorter in the two-step method group than in the conventional method group [238 (179-293) min vs 272 (189-347) min, P < 0.01]. No postoperative death occurred in either group. There was no significant difference in the rate of complications [14 (21.9%) vs 13 (22.4%), P = 0.55] or mean number of stapler cartridges used [5 (4-6) vs 5.2 (5-6), P = 0.007] between the two groups. CONCLUSION The two-step method for creating a gastric tube during laparoscopic-thoracoscopic Ivor-Lewis esophagectomy has the advantages of simple operation, minimal damage to the tubular stomach, and reduced use of stapler cartridges.

The lack of schedulability evaluation of previous charging schemes in wireless rechargeable sensor networks (WRSNs) degrades the charging efficiency, leading to node exhaustion. We propose an Optimal Path Planning Charging scheme, namely OPPC, for the on-demand charging architecture. OPPC evaluates the schedulability of a charging mission, which makes charging scheduling predictable. It provides an optimal charging path which maximizes charging efficiency. When confronted with a non-schedulable charging mission, a node discarding algorithm is developed to enable the schedulability. Experimental simulations demonstrate that OPPC can achieve better performance in successful charging rate as well as charging efficiency.

An antipodal Vivaldi antenna (AVA) with novel symmetric two-layer double-slot structure is proposed. When excited with equiamplitude and opposite phase, the two slots will have the sum vector of their E-field vectors parallel to the antenna’s plane, which is uniform to the E-field vector in the slot of a balanced AVA with three-layer structure. Compared with a typical AVA with the same size, the proposed antenna has better impedance characteristics because of the amelioration introduced by the coupling between the two slots, as well as the more symmetric radiation patterns and the remarkably lowered cross-polarization level at the endfire direction. For validating the analysis, an UWB balun based on the double-sided parallel stripline is designed for realizing the excitation, and a sample of the proposed antenna is fabricated. The measured results reveal that the proposed has an operating frequency range from 2.8 to 15 GHz, in which the cross-polarization level is less than −24.8 dB. Besides, the group delay of two face-to-face samples has a variation less than 0.62 ns, which exhibits the ability of the novel structure for transferring pulse signal with high fidelity. The simple two-layer structure, together with the improvement both in impedance and radiation characteristics, makes the proposed antenna much desirable for the UWB applications.