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Dense silty sediments exhibit complex rheological behaviors due to their particular sediment composition, which consists of sand, silt and clay. This paper investigated the rheological properties of ten dense silty sediments prepared with various percentages of kaolin. A set of rheological experiments was conducted with an MCR302 rheometer. Measurements of the flow curves, deformation curves, and shear stress-time response were made. The dense silty sediments underwent a solid-liquid transition during shear rate ramp tests, and the critical shear stress increased with decreasing median particle diameter D50. Thixotropy was common in the samples with smaller D50, but the samples with larger D50 displayed anti-thixotropic behavior. Both the power-law model and the Herschel-Bulkley model were selected to describe the rheological behavior, and the Herschel-Bulkley model was more suitable for samples with higher density and smaller D50. The parameters in the empirical expressions for calculating rheological parameters were obtained by a regression analysis.

Background: Case-based learning (CBL) and concept mapping (CM) are two important strategies in medical education. This study aimed to assess the effects of CBL combined with CM on medical students' learning in biochemistry course via comparison with didactic lectures. Methods: A total of 60 medical students from Hunan University of Medicine (China) in the first semester of their sophomore year were included in this study. Among them, 30 students were introduced to the innovative program consisting of CBL and CM, and 30 students attending didactic lectures formed the control group. A terminal examination and Likert questionnaires were employed to investigate the efficacy and possible advantages of the combination of CBL and CM when compared with didactic lectures. Results: Students attending the innovative program got higher scores in the final examination than those received didactic lectures. Majority students enjoyed the combination use of CBL and CM, and they generally approved oftheir positive effects on improving logical thinking abilities and helping to bridge the gap between the basic science and clinical practice. Moreover, 90% (27/30) students declared they would use CBL and CM in their future studies and works. Conclusion: The combination of CBL and CM had positive effects on learning outcomes of biochemistry and medical students' opinions regarding their combination were overwhelmingly positive.

The three-dimensional linear stability characteristics of two-layer immiscible fluid with a free surface are considered, wherein a Newtonian fluid contains a small amount of sediment particles, and overlies a lower fluid that contents hyperconcentration of sediment. Rheological experiments are carried out on three kinds of artificial sediments with different silt-kaolin mixing ratios to study the rheological properties of the lower fluid. The results show that the rheological properties of the lower fluid conform to the power-law model. Based on this, the modified N–S and Squire equations in each layer are derived for the gravity-driven flow, which are calculated by using the finite difference method. The effect of various dimensionless parameters, such as the viscosity ratio ( $$c_{m})$$ , the density ratio (s), the power-law index (n), and the thickness ratio ( $$h_{s})$$ on the instability characteristics of the flow is investigated. It is observed that increasing $$c_{m}$$ , s and $$h_{s}$$ is stabilizing for both long and short waves, which leads to an increase of the critical Reynolds number (Re $$_\mathrm{{{wcr}}})$$ , and a decrease of the bandwidth of the unstable wavenumbers. The disturbed velocities (u and w) are also decreased. Decreasing the shear-thinning tendency (increasing n) of the lower fluid is destabilizing for both long and short waves, which leads to a decrease of Re $$_\mathrm{{{wcr}}}$$ and an increase of the disturbed velocities.

To obtain the mechanical behavior response of the material under loading, a data-driven construction method of material mechanical behavior model is proposed, which is universal for predicting the mechanical behavior of any material under different loads. Based on the framework of artificial intelligence and finite element simulation, the method uses Python script to drive an Abaqus loop calculation to obtain data sets and performs artificial intelligence training on data sets to realize model construction. In this paper, taking the quasi-static tension of 9310 steel as an example, a material mechanical behavior model is constructed, and the accuracy of the prediction model is verified based on the experimental data. The results show that the simulation results are in good agreement with the experimental data. The error between the simulation results and the experimental results is within 2%, indicating that the model constructed by this method can effectively predict the mechanical properties of materials.

In this paper, the prediction model for ionospheric total electron content (TEC) based on Long Short-Term Memory (LSTM) deep learning network and its performance are discussed. The input parameters of the model are previous values of daily TEC, solar radio flux at 10.7 cm parameter of 81 day moving average ( $\overline{F107\_81}$ ), sunspot number (SSN), geomagnetic Kp index, and disturbance storm time (Dst) index, and the outputs are TEC values for the target day. TEC data from January 1, 2001 to December 31, 2016 were used in this study. The dataset almost covers most of the years of the last two solar cycles (23, 24), and it is separated as 81.3% for training, 6.2% for validation, and 12.5% for testing. At BJFS IGS station (39.61° N, 115.89° E), LSTM yielded good TEC estimates with an RMSE of 4.07 TECU in 2001, it was 33% and 48% lower than the RMSE observed in TEC prediction using BP and IRI-2016 models, respectively. In the year of low solar activity (2016), the RMSE predicted by LSTM was 1.78 TECU, it provided 30% and 54% lower RMSE for TEC prediction than for BP and IRI-2016 models. Under the condition of magnetic storm, the LSTM TEC predictions are more consistent with the corresponding IGS Global Ionospheric Maps (GIMs) TEC than TEC predictions by BP and IRI-2016 models. LSTM can better grasp the influence of different external conditions on TEC. Seventeen grid points along 120° E meridian in latitude range from 80° S to 80° N were selected to further study the performance of LSTM model in different latitude. Results show that the prediction accuracy of LSTM is better than that of BP at different latitudes, especially at low latitudes. The performances of the two models are highly correlated with latitude and solar activity, and are both better than that of IRI-2016.

Mitochondrial dynamic imbalance associates with several cardiovascular diseases. However, the role of mitochondrial dynamics in TLR4 activation-mediated dilated cardiomyopathy (DCM) progress remains unknown. A model of experimental autoimmune myocarditis (EAM) was established in BALB/c mice on which TLR4 activation by LPS-EB or TLR4 inhibition by LPS-RS was performed to induce chronic inflammation for 5 weeks. TLR4 activation promoted the transition of EAM to DCM as demonstrated by increased cardiomyocyte apoptosis, myocardial fibrosis, ventricular dilatation, and declined heart function. TLR4 inhibition mitigated the above DCM changes. Transmission electron microscope study showed that mitochondria became fragmented, also with damaged crista in ultrastructure in EAM mice. TLR4 activation aggravated the above mitochondrial aberration, and TLR4 inhibition alleviated it. The mitochondrial dynamic imbalance and damage in DCM development were mainly associated with OPA1 downregulation, which may be caused by elevated TNF-α level and ROS stress after TLR4 activation. Furthermore, OMA1/YME1L abnormal degradation was involved in the OPA1 dysfunction, and intervening OMA1/YME1L in H9C2 significantly alleviated mitochondrial fission, ultrastructure damage, and cell apoptosis induced by TNF-α and ROS. These data indicate that TLR4 activation resulted in OPA1 dysfunction, promoting mitochondrial dynamic imbalance and damage, which may involve in the progress of EAM to DCM.

The work herein describes a novel technique, a rotating packed bed (RPB) combined with a charged device, to remove fine particles from gas steam. Experiments were carried out to investigate the effects of different operating conditions, including the packing type, packing thickness, rotation speed, gas–liquid volumetric ratio, initial fine particle concentration, and voltage, on the removal efficiency of fine particles from a gas stream. Results show that total removal efficiencies of fine particles and particles with a size of less than 2.5 μm (PM2.5) can reach up to 99 and 96%, respectively, under the operating conditions of packing thickness of 60 mm, rotation speed of 1000 rpm, gas–liquid volumetric flow ratio of 400, voltage of 40 kV, and use of a fine metal gauze packing. In addition, a correlation to predict PM2.5 removal efficiency was established, and results show that the predicted values of outlet PM2.5 concentrations are in agreement with experimental data, with deviations of ±20%. This work d...

Low-density lipoprotein cholesterol (LDL-C) has been demonstrated as an independent risk factor of ischemic stroke, but the association of LDL-C with ischemic stroke in patients with nonvalvular atrial fibrillation (AF) remains uncertain. Our objective was to explore whether LDL-C could refine stroke stratification in patients with AF. A total of 424 nonvalvular patients with AF with ischemic stroke and 391 ones without ischemic stroke were enrolled. No patient had received antithrombotic therapy. Multivariate logistic regression analysis showed that LDL-C was an independent predictor of ischemic stroke in patients with AF, with the adjusted odds ratio of 2.004 (95% confidence interval 1.624 to 2.473; p

Although most of the existing encryption system takes the privacy issues of storing data into consider, the reveal of user access pattern is inevitable during the e-mail filtering. Therefore, how to protect the private data in the process of spam filtering becomes one of the urgent problems to be solved. Combined with two filtering techniques which are based on keyword and blacklist respectively, this paper achieves the goal of sorting and filtering spams. Meanwhile, given the privacy issues in sorting and filtering the spams, the paper is based on an experimental project, the Pairing Based Cryptography, which is performed by Stanford University to achieve the e-mail encryption program. It adopts a searchable public key encryption in the process of sorting and filtering, which needs no decryption and can realize searching and matching operations. By this method, it fully protects the privacy and access patterns of the mail receiver from disclosing.

Wireless sensor network consists of a large number of tiny sensor nodes owned capable of perception in monitoring region by self-organized wireless communication, has been widely applied in military and civil fields. From the perspective of resource- saving, under the condition of the network’s connectivity and specific coverage, the number of sensor nodes is assumed to be opened as few as possible. So, computing the sensor nodes collection which meeting the requirements is called the problem of network coverage optimization for Wireless Sensor Network; also called the problem of minimum connected covering node set. The innovation point of the article is: Firstly, it analyzed the deficiencies of traditional evolution algorithm fitness function, put forward an improved fitness function design scheme, and has been proved that it has advantage of solving problem on wireless sensor networks coverage optimization; Secondly, it applied the method of control variables, comparison and analysis of the influence on the various operations and parameters selection in evolution algorithm on the optimization results and performance, and then point out how to design algorithm to manage to the best optimize effect and performance.

Although most of the existing encryption system takes the privacy issues of storing data into consider, the reveal of user access pattern is inevitable during the e-mail filtering. Therefore, how to protect the private data in the process of spam filtering becomes one of the urgent problems to be solved. Combined with two filtering techniques which are based on keyword and blacklist respectively, this paper achieves the goal of sorting and filtering spams. Meanwhile, given the privacy issues in sorting and filtering the spams, the paper is based on an experimental project, the Pairing Based Cryptography, which is performed by Stanford University to achieve the e-mail encryption program. It adopts a searchable public key encryption in the process of sorting and filtering, which needs no decryption and can realize searching and matching operations. By this method, it fully protects the privacy and access patterns of the mail receiver from disclosing.

Simulation software Arena is used to build fishing port system simulation model. According to the actual operation characteristics of the fishing port, the flexible berthing way is to assign a certain length of coastline in accordance with the length of the fishing boat, no fixed berths. Through many simulation experiments, reasonable length of coastline corresponding to different annual throughput is obtained. After analyzing the simulation results, the author achieves the formula for calculating the corresponding reasonable length of shoreline, which can be used as a fishing port planning and design.

In this article, fish piers are divided into two categories, piers for unloading fish and providing ice. First of all, the number of berths and pier length are obtained on the condition of discharging quantity of products in the dock, in different years, according to the original standard formulas. Then, the operation process of fishing boats in the ports is simulated on the method of Arena software. The reasonable coastline length corresponding to discharging quantity of products in the dock, in different years, is obtained. Last, the simulation results are compared with the theoretical results. The reasonable coastline length of piers for unloading fish and providing ice are obtained, corresponding to discharging quantity of products in the dock in different years.

Salviae miltiorrhiza (Danshen) has been used for thousands of years in China and some other Asian countries to treat atherothrombotic diseases. Salvianolate which consists of three water-soluble ingredients purified from Salviae miltiorrhiza, has been approved by Chinese SFDA to treat coronary artery disease. So far, there is no evidence clearly showing the clinical efficiency of salvianolate and the underlying mechanism. This study is to evaluate the effects of salvianolate on platelets in patients with acute coronary syndrome and explore the underlying mechanism. We evaluated the effects of salvianolate on platelets in patients with acute coronary syndrome by measuring ADP-induced PAC-1 binding and P-selectin expression on platelets. Salvianolate significantly potentiated the antiplatelet effects of standard dual antiplatelet therapy. We also investigated the antiplatelet effects of salvianolatic acid B (Sal-B), the major component which composes 85% of salvianolate. Sal-B inhibits human platelet activation induced by multiple agonists in vitro by inhibiting phosphodiesterase (PDE) and antagonizing P2Y12 receptor. For the first time, we show the antiplatelet efficiency of salvianolate in ACS patients undergoing treatment with clopidogrel plus aspirin, and demonstrate that Sal-B, the major component of salvianolate inhibits human platelet activation via PDE inhibition and P2Y12 antagonism which may account for the clinical antiplatelet effects of salvianolate. Our results suggest that Sal-B may substitute salvianolate for clinical use.

In wireless sensor networks, computing the sensor nodes collection that meets the requirements is called the problem of network coverage optimisation for wireless sensor network; also called the problem of minimum connected covering node set. The innovation points of this article are as follows: Firstly, it analyses the deficiencies of traditional evolution algorithm fitness function, puts forward an improved fitness function design scheme, and proves that it has advantage of solving problem on wireless sensor networks coverage optimisation. Secondly, it applies the method of control variables, comparison and analysis of the influence on the various operations and parameters selection in evolution algorithms on the optimisation results and performance, and then points out how to design algorithms to best optimise effect and performance.

there are lots of sensitive and confidential data in financial field, such as credit card number, stock number, fund number and so on. Therefore, top level security requirement is always required in financial systems, where a good access control framework is necessary. Traditional role-based access control frameworks lack of control in data access granularity and often slow down the system, even though it provides an efficient access control model which can restrict users' operation according to their roles. They can hardly meet the requirements in large financial system. This article proposes and implements a Three- Layer Role-based Access Control framework (TL-RBAC) which can perfectly meet the requirements in large financial system. TL-RBAC implements access control in three layers: web pages, operations and data. Coarse-grained access control in web pages layer is used to filter anonymous attacks such as web scan and DoS attacks. Fine-grained access control in operations and data layers guarantee that the user cannot do operations and access data out of his privilege. Performance testing report of the system shows that TL-RBAC meets the performance requirement in terms of system throughput and time per operation. In order to meet security requirements of the financial system without system performance depreciation, this paper extend traditional RBAC model, designs and implements a Three-Layer Role-based Access Control (TL-RBAC). The first layer is coarse-grained access control to web pages implements by SiteMinder, which is an access control production of CA. The second layer is in web application, it makes access control by associating users and their operations. The third layer is fine-grained access control implements through database store procedure. Coarse-grained access control layer is used to filter illegal operation and hackers' attack in large scale to accelerate frequent access control. Fine-grained access control is used to bind user to the data within his privilege. In this case, user can't do any operations beyond his privilege under TL-RBAC framework and also achieves great performances in terms of throughput and time per operation.