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Collision avoidance implies that extra motion in joint space must be taken, which might exert unexpected influences on the execution of the desired end-effector tasks. In this paper, a novel framework for generating collision-free trajectories while respecting task priorities is proposed. Firstly, a data-driven approach is applied to learn an efficient representation of the distance decision function of the system. The function is then working as the collision avoidance constraints in the inverse kinematics (IK) solver, which avoids the collision between manipulators. To eliminate undesired influences of the extra motion for collision avoidance on the execution of tasks, task constraints are proposed to control the task priorities, offering the system with the ability to trade off between collision avoidance and task execution. Furthermore, the overall framework is formulated as a QP (quadratic programming), therein guarantees a real time performance. Numerical simulations are conducted to demonstrate the effectiveness and efficiency of the presented method.

Drastic reduction in biodiversity has been a severe threat to ecosystems, which is exacerbated when losing few species leads to disastrous and even irreparable consequences. Therefore, revealing the mechanism underlining biodiversity loss is of uttermost importance. In this study, we show that abundant indirect interactions among mutualistic ecosystems are critical in determining species' status. Combining topological and ecological characteristics, we propose an indicator derived from a dynamic model to identify keystone species and quantify their influence, which outperforms widely-used indicators like degree in realistic and simulated networks. Furthermore, we demonstrate that networks with high modularity, heterogeneity, biodiversity, and less intimate interactions tend to have larger indirect effects, which are more amenable in predicting decline of biodiversity with the proposed indicator. These findings shed some light onto the influence of apposite biodiversities, paving the way from complex network theory to ecosystem protection and restoration.

In view of increasing concerns about climate change and global warming, various renewable energy sources are widely adopted in power systems to reduce greenhouse gas emissions. However, the widespread adoption of renewable energy sources exacerbates the problem of harmonics pollution. In order to improve power quality, it is urgent to develop a new approach for monitoring harmonics. By leveraging the structured sparsity and spatial sparsity of harmonic sources, this paper proposes a group sparse Bayesian learning method for solving harmonic state estimation problems. The proposed algorithm can employ a small number of measurements less than the number of state variables to pinpoint harmonic sources and to estimate the harmonic magnitudes and angles. Moreover, the proposed method achieves automatic hyperparameter adjustments and solves the system states in complex domain without splitting them into real and imaginary parts. Extensive results on a benchmark IEEE 14-bus system are presented to substantiate the superiority of the proposed method in terms of localization accuracy and harmonic magnitude and phase angle estimation.

Chatter is a typical kind of unstable dynamics often encountered in machining processes, which often results in overcut and rapid tool wear. Hence, chatter phenomenon worsens the surface quality and reduces productivity in milling systems as well. Recent years have witnessed a surging industrial demand of high quality and high efficiency machining. Specifically, for low radial immersion milling situation, large depth of cuts is inevitably needed so as to increase the machining efficiency. To fulfill such a task, this paper develops a robust active control method to mitigate the chatter dynamics of low radial immersion milling processes. The present approach increases the axial depth of cuts, and the improvement is inversely proportional to the radial immersion ratio. Finally, case studies are conducted to show the substantially enlarged stable region in the stability lobe diagram (SLD) spanned by spindle rotational speed and axial depth of cut. Thus, the method can be expected to improve the efficiency of milling processes. Note to Practitioners —This paper seeks to mitigate machining chatters that worsen the workpiece surface quality in high-speed machining processes. To overcome such unexpected effects, traditional passive schemes simply adjust the rotational speed and cutting depth, which do not seek assistance from external power sources. Hence, neither the damping nor stiffness of the system can be changed, and a high maximal material removal rate (MMRR) is arduous to obtain. By contrast, this paper develops a robust active control method to mitigate the chatter dynamics for low radial immersion milling. In the design stage of the milling spindle, two active magnetic bearings (AMBs) are embedded in the tool house as control actuators, which produce extra force to counteract the chatters. In real milling processes, the chatters are detected by the associated inductive displacement sensors around the AMBs, and an uncertainty model is accordingly established with low radial immersion. With the detected vibration displacements, robust active control signals are calculated online, and then fed into the power amplifiers to drive the two AMBs. By this means, a closed-loop active control system is thus established for milling processes, which substantially enlarges the stable region of the SLD spanned by rotational speed and cutting depth. As a result, the proposed active control scheme can be expected to increase the MMRR and, hence, to enhance the productivity of milling processes.

A new pregnane-type steroid, 2α,3β,16β-trihydroxy-5α-pregnane-20R-methacrylate (1), was isolated from the leaves of Melia azedarach, together with 17 known compounds. Their structures were elucidated by spectroscopic and mass-spectrometric analysis, including 1D, 2D NMR, ESI-MS, and HR-MS. Compound 1 was found to possess cytotoxicities against HepG2, K562, and SGC7901 cell lines, with IC50 values 18.6, 19.1, and 62.9 μM, respectively.

Rotor active magnetic bearing (rotor-AMB) systems are frequently used to alleviate vibrations for various applications such as in national defense, manufacturing industries, IC production, and aerospace engineering.One obstacle to improve machining efficiency and quality is the open-loop instability of rotor-AMB systems during the machining process. We built a closed-loop processing platform using aspindle rotor installed with AMBs and thereby developed a rotor-AMB suspension system embedded with a dual-mode predictive controller (DMPC).The performance of the system is thus substantially improved. In the proposed DMPC, both model-based prediction and receding horizon optimization are utilized to guarantee the closed-loop stability of the rotor-AMB suspension systems with input constraints. Finally, the effectiveness and superiority of the proposed method are examined through substantial levitation experiments on a machining platform with installed AMBs.

Active magnetic bearing (AMB) rotor system is widely applied in the industry for its remarkable advantages. However, it is a typical open-loop unstable mechatronics system suffering from nonlinear and couple characteristic. In this paper, the feedforward decoupling method is used to deal with the couple relationship of different axes. And the model reference adaptive control (MRAC) method is applied to improve the control performance and robustness and overcome the uncertainties. This control method makes the system output reach to the reference model by the designed adaptive law. Simulation results illustrate the effectiveness of the proposed scheme.

The cooling curves and the change of contraction/expansion during solidification and cooling were tested by using a self-made device which could achieve the one-dimensional contraction instead of three-dimensional contraction of the casting. Then, the effects of Al content (0, 1.1, 3, 5, 10, 12.9, 15, 17, 19, 22, 24 and 30 wt%) on the thermal contraction/expansion of the binary Mg–Al as-cast alloys during solidification were obtained. The results showed that expanding instead of contraction was present in Mg–Al alloys with the addition of 0–30 wt% Al during solidification. The values of expansion significantly increased at first and then decreased with the increase in Al content. And the maximum expansion ratio of 0.44% (maximum expansion value: 0.841 mm) was present in the Mg–15 wt% Al alloy. Contraction instead of expansion occurred once the temperature drops to the temperature corresponding to the expansion value in total, indicating the occurrence of a continuous expansion during the solidification process in mushy zone for the Mg alloys with Al addition of 5–30 wt%. The expansion value in total consisted of two parts: the expansions occurring in the liquid-phase zone and mushy zone. The expansion in liquid zone was present in every Mg–Al alloy, and it contributed to the most proportion of the total expansion value when the Al content in Mg–Al alloy was lower than 10 wt% or higher than 22 wt%. However, the total expansion value was mainly determined by the solidification behavior in mushy zone when the Al content was among 10–22 wt% in Mg–Al alloys.

Objective To compare arteriovenous flush with heparin and argatroban and observe its effect on platelet counts, biochemical index and the incidence of thrombocytopenia (HIT). Methods Retrospective analysis for 746 cardiovascular surgery patients, who were divided into heparin group (350 cases, 10 mg heparin dissolved in 250 ml of saline) and argatroban group (396 cases, 2.5 mg argatroban dissolved in 250 ml saline). Monitoring the changes of platelet count, hepatic function, renal function and blood coagulation index, hemorrhage and thrombosis incidence were monitored in two groups. HIT related 4Ts score, HIT incidence and complications were also recorded. Results There was no significant difference in basic clinical data between the two groups. There was no difference in platelet counts between the two groups before and after the operation, and the platelets of heparin group were significantly lower than that of the argatroban group on the first day and the 5th day after surgery. According to 4Ts score, 13 patients in heparin group got medium and high score of 4Ts, of whom 7 patients were positive for antibody (2.0%), and then standard anti-coagulation therapy was initiated for antibody positive patients. There were 5 patients in argatroban group getting medium and high score of 4Ts, and 2 were HIT antibody positive (0.5%). As such, the standard anti-coagulation therapy was also performed on these patients, and no bleeding event occurred. The total number of thrombosis events were more in the heparin group than in the argatroban group. There was no statistically significant difference between the two groups in hepatic, renal function index and coagulation index. Conclusions Postoperative routine use of arteriovenous flush with argatroban for anticoagulation has litte effect on platelet count, could reduce the incidence of HIT and does not increase the risk of bleeding. DOI: 10.11855/j.issn.0577-7402.2018.06.13

Spatiotemporal characteristics of human mobility emerging from complexity on individual scale have been extensively studied due to the application potential on human behavior prediction and recommendation, and control of epidemic spreading. We collect and investigate a comprehensive data set of human activities on large geographical scales, including both websites browse and mobile towers visit. Numerical results show that the degree of activity decays as a power law, indicating that human behaviors are reminiscent of scale-free random walks known as Levy flight. More significantly, this study suggests that human activities on large geographical scales have specific non-Markovian characteristics, such as a two-segment power-law distribution of dwelling time and a high possibility for prediction. Furthermore, a scale-free featured mobility model with two essential ingredients, i.e., preferential return and exploration, and a Gaussian distribution assumption on the exploration tendency parameter is proposed, which outperforms existing human mobility models under scenarios of large geographical scales.

Objective This study is designed to investigate the effect of the peptide from Eucheuma on platelet aggregation and mouse tail thrombosis induced by carrageenan. Methods The peptide was purified from Eucheuma using sephdexG-50 gel chromatography and HPLC. The inhibitory effects of peptide on platelet aggregation induced by adenosine diphosphate (ADP)/ thrombin were detected by light transmittance aggregometry. The platelet were treated with normal saline or Eucheuma peptides (2.5, 5.0, 10.0μg/ml). The platelet aggregation was detected by FLASH continuous spectral fluorescence microplate reader, and the maximum platelet aggregation rate (MAR) was calculated. The peptide (15, 30, 60mg/kg) and 100mg/kg clopidogrel were intraperitoneal injected into mice for 7 days to confirm the anti-thrombosis activity of the peptide in carrageenan-induced mouse tail thrombosis model. Results The platelet aggregation can be inhibited by the peptide. Comparing the maximum platelet aggregation rate induced by ADP, the results showed that control group was 100%, 2.5μg/ml peptide group was 61.84%, 5.0μg/ml peptide group was 71.04% and 10.0μg/ml peptide was 60.95%. The maximum platelet aggregation rate induced by thrombin was also tested. The results showed that control group was 100%, 2.5μg/ml peptide group was 75.34%, 5.0μg/ml peptide group was 69.96% and 10.0μg/ ml peptide group was 73.74%. The thrombosis rate (2.5μg/ml peptide group was 36.89%, 5.0μg/ml peptide group was 17.25%, 10.0μg/ml peptide group was 22.99%, and 100mg/kg clopidogrel group was 18.96%, respectively) and the length of thrombus in mice can be reduced by the peptide (15-60mg/kg). Conclusions The carrageenan induced tail thrombosis in mice can be inhibited by the peptide of Eucheuma. It is suggested that the peptide of Eucheuma is a potential compound in anti-thrombosis. DOI: 10.11855/j.issn.0577-7402.2018.02.02

Two new phenylspirodrimanes, stachybotrin H (1) and stachybotrysin H (9) together with eleven known analogues (2–8, 10–13) were isolated from deep-sea derived Stachybotrys sp. MCCC 3A00409. Their structures were determined by extensive NMR data and mass spectroscopic analysis. Compounds 9–12 showed weak cytotoxicity against three human cancer cell lines K562, Hela and HL60 with IC50 in the range of 18.5–52.8 μM.

This note develops a discrete-time predictor feedback control scheme for continuous-time multiagent systems with input and communication time delays. With measurement of locally available relative state signals among neighbored agents, the controller is able to achieve consensus for a large variety of linear open-loop agent dynamics, including exponentially unstable systems. Moreover, the new design can deal with arbitrarily large time delays in some special scenarios. The feature of discrete-time and relative state measurement substantially saves implementation cost compared with the existing methods in the literature. Numerical simulation demonstrates the effectiveness of the proposed theoretical design.

In this paper, the effect of deposition velocity on bonding degree is studied in the aspects of experiment and theory. The experimental results show that the bonding quality of the adjacent filaments is weakened with increasing of deposition velocity. In addition, on the premise of guaranteeing every point in the building process to remain at the optimal temperature, the quantitative relationships between interval and filled area, deposition velocity are investigated by using the technique of deactivate and reactivate element of finite element. On the base of the quantitative relationships, the variable deposition velocity printing method is proposed for the first time. Namely, to reap the best bonding quality of filaments the time of completing one layer can be determined according to the filled area, and then, the optimal deposition velocity can be obtained according to the quantitative relationship between the interval and the deposition velocity. Printing the model at this speed can obtain the part with the best bonding quality between adjacent layers.

The research analyzed the distribution of cutter position point data outputted by software CAM, based on the precision of surface milling. The model of the tool-path is established by using the piece-wise interpolation function, combining with the distribution characteristic of cutter position point. The segmentation optimization of the tool-path is also realized via the limitation and judgment of the string high error of the segmented trajectory and the optimization algorithm is integrated into the post-processing to improve the precision of the surface milling. The experiment results of surface milling show a positive effect of cutter position point optimization on surface milling accuracy.

Background/Aims: Chinese angelica polysaccharide (CAP) is the main effective ingredient of angelica sinensis and exerts anti-inflammatory and anti-apoptotic effects on many diseases. This study aimed to explore the pharmacological potential of CAP on spinal cord injury (SCI). Methods: PC12 cells were pretreated by CAP and were subjected to LPS. Transfection was performed to alter the expression of COX-1. Cell viability and apoptotic cell rate were measured by CCK-8 and flow cytometry respectively. qRT-PCR and western blot analysis were performed to assess the expression changes of pro-inflammatory cytokines, apoptosis-related factor and core kinases in PI3K/AKT pathway. Results: LPS stimulation induced significant cell damage in PC12 cells as cell viability was repressed, apoptosis was induced and the expression levels of IL-1β, IL-6, IL-8, and TNF-α were increased. CAP pretreatment protected PC12 cells against LPS-induced cell damage. Meanwhile CAP treatment reduced the expression of COX-1 even in LPS-stimulated PC12 cells. More importantly, COX-1 overexpression abolished the protective effects of CAP on LPS-injured PC12 cells. Finally, Western blot analytical results showed that CAP activated PI3K/AKT pathway also in a COX-1-dependent manner. Conclusion: CAP exerted anti-apoptotic and anti-inflammatory effects on LPS-injured PC12 cells via down-regulation of COX-1.

The fluctuations in electricity prices and intermittency of renewable energy systems necessitate the adoption of online energy management schemes in industrial microgrids. However, it is challenging to design effective and optimal online rolling horizon energy management strategies that can deliver assured optimality, subject to the uncertainties of volatile electricity prices and stochastic renewable resources. This paper presents an adaptable online energy management scheme for industrial microgrids that minimizes electricity costs while meeting production requirements by repeatedly solving an optimization problem over a moving control window, taking advantage of forecasted future prices and renewable energy profiles implemented by a hybrid deep learning model. The predicted values over the control horizon are assumed to be uncertain, and a multivariate Gaussian distribution is used to handle the variations in electricity prices and renewable resources around their predicted nominal values. Simulation results under different scenarios using real-world data verify the effectiveness of the proposed online energy management scheme, assessed by the corresponding gaps with respect to several selected benchmark strategies and the ideal boundaries of the best and worst known solutions. Furthermore, the robustness of the scheme is verified by considering severe errors in forecasted electricity prices and renewable profiles.

Alternaria blotch, Brown spot, Mosaic, Grey spot, and Rust are 5 common apple leaf diseases that severely impact apple production and quality. At present, although many CNN methods have been proposed for apple leaf diseases, there are still lack of apple leaf disease detection models that can be applied on mobile devices, which limits their application in practical production. This paper proposes a light-weight CNN model that can be deployed on mobile devices to detect apple leaf diseases in real time. First, a dataset of apple leaf diseases composed of simple background images and complex background images, which is called AppleDisease5, is constructed via data augmentation technology and data annotation technology. Then a basic module called MEAN block(Mobile End AppleNet block) is proposed to increase the detection speed and reduce model’s size by reconstructing the common 3 × 3 convolution. Meanwhile, the Apple-Inception module is built by introducing GoogLeNet’s Inception module and replacing all 3 × 3 convolution kernels with MEAN block in Inception. Finally, a new apple leaf disease detection model, MEAN-SSD(Mobile End AppleNet based SSD algorithm), is built by using the MEAN block and Apple-Inception module. The experiment results show that MEAN-SSD can achieve the detection performance of 83.12% mAP and a speed of 12.53 FPS, which illustrates that the novel MEAN-SSD model can efficiently and accurately detect 5 common apple leaf diseases on mobile devices.

IntroductionPostoperative infection (PI) is one of the main severe complications after cardiovascular surgery. Therefore, antibiotics are routinely used during the first 48 hours after cardiovascular surgery. However, there is no effective method for early diagnosis of infection after cardiovascular surgery, particularly, to determine whether postoperative patients need to prolong the use of antibiotics after the first 48 hours. In this study, we aim to develop and validate a diagnostic model to help identify whether a patient has been infected after surgery and guide the appropriate use of antibiotics.Methods and analysisIn this prospective study, we will develop and validate a diagnostic model to determine whether the patient has a bacterial infection within 48 hours after cardiovascular surgery. Baseline data will be collected through the electronic medical record system. A total of 2700 participants will be recruited (n=2000 for development, n=700 for validation). The primary outcome of the study is the newly PI during the first 48 hours after cardiovascular surgery. Logistic regression penalised with elastic net regularisation will be used for model development and bootstrap and k-fold cross-validation aggregation will be performed for internal validation. The derived model will be also externally validated in patients who are continuously included in another time period (N=700). We will evaluate the calibration and differentiation performance of the model by Hosmer-Lemeshow good of fit test and the area under the curve, respectively. We will report sensitivity, specificity, positive predictive value and negative predictive value in the validation data-set, with a target of 80% sensitivity.Ethics and disseminationEthical approval was obtained from Medical Ethics Committee of Affiliated Nanjing Drum Tower Hospital, Nanjing University Medical College (2020-249-01).Trial registration numberChinese Clinical Trial Register (www.chictr.org.cn, ChiCTR2000038762); Pre-results.

A large part of biological collective behaviors involves motional formation patterns like migration, vortex, aggregation, etc., in three-dimensional space, but the phase transition principles among these patterns still remain a dilemma. In this letter, by tweaking the vision range of the particles in a minimal collective motion model, phase transitions are observed among gas-like, crystal-like, and liquid-sphere–like patterns. Significantly, the increase of noise magnitudes will destroy the moving direction synchronization of gas-like and crystal-like phases, but not the liquid-sphere–like phase. By contrast, three sub-phases of migration liquid-sphere, vortex liquid-sphere and aggregation liquid-sphere emerge by slightly increasing noise magnitudes. This study sheds some light onto the forming mechanisms of 3D motional patterns of abundant biological groups. These insights could be expected to enable tuning the collective motional formations of multi-unmanned systems or robots by simply tweaking a few dynamical parameters as well.

These years have witnessed increasing research works and new technologies on manufacture of micro-/nanoscale flexible and tractile electronic devices. Orderly bead-on-string microstructures fabricated by electrospinning processes have applications in flexible and tractile sensors, artificial tissues and energy harvesters. In this paper, a feedback control system is established for sedimentary microstructures produced by electrospinning processes. This system is composed of a high-speed camera, an National Instruments (NI) image processor, an NI controller, and a linear machine regulating the substrate velocity. A robust model predictive control (MPC) method is developed on practical electrospinning processes to improve the regularity of the sedimentary bead-on-string pattern suffered by external disturbances and system uncertainties. Extensive experimental results have verified that the interbead gap becomes tunable and stabilized by the closed-loop MPC controller actuated by the linear machine. This controller is beneficial to enhance the consistency and controllability of the microelectrical elements. More significantly, the adjustability of the interbead gap enables the manufacturing of uniform microstructures widely used in microscale sensors and electrical units manufacturing and tissue engineering.

This letter reports on the synthesis of Fe3O4@graphene composites (FGC) and their applications as anode materials in lithium-ion batteries (LIBs). As an anode material for LIBs, the FGC exhibited discharge and charge capacities of 1354 and 953 mAh g−1 in the initial cycle at 200 mA g−1, respectively. And more impressively, 639 mAh g−1 was remained after a twenty-five fold increase in current density to 5 A g−1. Especially, the capacity steadily maintained at 788 mAh g−1 even after 500 charge-discharge cycles at 1 A g−1. Such a high capacity and excellent cycling stability can be attributed to the strongly coupled interactions between graphene sheets and Fe3O4 NPs.

Objective To investigate the effects of saturated fatty acids and unsaturated fatty acids on proliferation and autophagy of human lung cancer cells. Methods The lung cancer cells A549 were treated with stearic acid (saturated fatty acid) and doconexent (DHA, unsaturated fatty acid), respectively, in concentrations of 0, 30, 60, 120 and 240μmol/L. MTT test and cell clone formation assay were performed to detect the proliferation of A549 cells. The morphology of A549 autophagy was observed by confocal laser scanning microscopy after A549 cells were treated with stearic acid or DHA for 24 hours. Western blotting assay was used to detect the expression of autophagy-related protein after A549 cells were treated with stearic acid or DHA for 12, 24 and 36 hours, respectively. Results 30-240μmol/L stearic acid or DHA both inhibited the proliferation of A549 cells (P

Consensus of a network with a directed acyclic graph, a directed graph with no directed cycles, is always guaranteed if it contains a spanning tree. This paper studies the effect of adding edges to a directed acyclic graph that may result in a directed cycle. It is shown that the effect on consensus performance of the whole network is only determined by a local subnetwork containing all the added edges. More specifically, both a one-dimensional (1-D) chain network and a 2-D grid network are investigated in this paper. It is proved that, when a reverse edge is added, the consensus performance is degraded by the amount only determined by the edge range, that is, independent of the network size or the location of the added edge.

To deeply understand the effects of pressure on microstructural evolutions and mechanical properties, a molecular dynamics simulation study has been performed under pressures of 0–50 GPa for liquid Ni 64 Zr 36 alloy during solidification process. Adopting several microstructural analyzing methods, especially the cluster-type index method (CTIM-3) to analyze the local microstructures in the system, it is found that the icosahedral cluster (12 0 12 0 0 0 0 0 0) and the defect icosahedral cluster (12 0 8 0 0 0 2 2 0), (12 2 8 2 0 0 0 0 0) play a key role during the microstructural transitions. All the solidified structures are of amorphous structures consisted of various basic clusters and their combinations with different sizes. It is worth noting that all the glass transition temperature T g , main bond-types, main basic clusters and elastic constants are almost increased linearly with the increase of pressure. Especially, the amorphous structure formed under 50 GPa would possess the admirable microstructural configuration and excellent mechanical properties of materials.

This paper establishes a general sampled-data framework for robust output synchronization of nonlinear heterogeneous multi-agent system in the lower-triangular form. Inspired by our previous work, this problem can be solved in a two-step manner: (1) sampled-data perturbed consensus, and (2) sampled-data perturbed output regulation. These two steps are coupled by a small gain condition which must be satisfied to ensure the robust output synchronization is achieved. We will first show that the sampling conditions on accomplishing sampled-data perturbed consensus and perturbed output regulation separately. In addition, we strengthen our previous small gain condition to incorporate the sampling effort. The sampled-data synchronization controller can be designed provided that the sampling condition satisfies some additional condition.

This paper proposes an image-guided depth super-resolution framework to improve the quality of depth map captured by low-cost depth sensors, like the Microsoft Kinect. First, a contour-guided fast marching method is proposed to preprocess the raw depth map for recovering the missing data. Then, by using the non-local total generalized variation (NL-TGV) regularization, a convex optimization model is constructed to up-sample the preprocessed depth map to a high-resolution one. To preserve the sharpness of depth discontinuities, the color image and its multi-level segmentation information are utilized to assign the weights within the NL-TGV through a novel weight combining scheme. The texture energy from color image and local structure coherence around neighbor pixels in low-resolution depth map are applied to adjust the combination weights for further suppressing texture-transfer. Quantitative and qualitative evaluations of the proposed method on the Middlebury datasets and real-sensor datasets show the promising results in quality.

Due to its superb flexibility, efficiency, and tractility, flexible electronic production is widely used in the manufacturing of thin-film solar cells, microscale sensors, high-resolution displayers, illumination equipments, and integrated artificial tissues. Electrospinning is an essential procedure in flexible electronic production, where a microscale/nanoscale fiber is dragged from a Taylor cone by a static electrical field power and afterward be deposited onto a flexible substrate. In this brief, we established a closed-loop control system of electrospinning processes composed of a high-speed camera, an National Instruments (NI) image processor, an NI controller, a control signal amplifier, and a high-voltage static electricity supplier. It is the first time to apply model predictive control on practical electrospinning processes to modulate the diameter of electrospinning fiber subject to external disturbances and uncertainties. Extensive experimental results have shown that the fiber diameter becomes tunable and stabilized by the closed-loop controller, which is beneficial to enhance the consistency and controllability of the microelectrical elements. More significantly, the adjustability of fiber diameter enables the manufacturing of more specified structures like island–bridge microstructure widely used in microscale sensors and electrical unit manufacturing and tissue engineering.

Thin-walled flexible workpieces are known to be the most commonly used flexible elements in mechanical structures and machines in the industries of aerospace, national defense, integrated circuit production, and so on. The bottleneck of improving machining quality of thin-walled flexible workpieces lies in the workpiece deformation during machining processes. We hereby establish a machining platform for thin-walled flexible workpieces and develop a purely data-driven Sparse Bayesian learning-based method to predict the future deformation merely by using historical displacement information. Accordingly, a dual-mode predictive controller is developed to mitigate the machining vibrations, and the quality of the workpiece surface has been thus substantially improved. Finally, the superiority and effectiveness of our proposed method are demonstrated through extensive machining experiments of thin-walled flexible workpieces.

Early mortality and cerebral injury are severe complications of aortic arch surgery, but data from Asian countries are scarce. We reviewed the results of patients who underwent aortic arch replacement with deep hypothermic circulatory arrest (DHCA) and antegrade selective cerebral perfusion (ASCP) at our institution to analyse pre- and intraoperative predictors of early death and neurological complications.Clinical data of adult patients who underwent aortic arch surgery with DHCA plus ASCP between January 2005 and December 2011 were retrospectively analysed. Univariate and multivariate analyses were performed to identify predictors of adverse outcome defined as 30-day mortality and permanent neurological dysfunction (PND), and transient neurological dysfunction (TND).A total of 626 patients were included in the study. The average age of the patients was 45.0±10.7 years with male predominance (77.0%). The incidence of adverse outcome was 5.8%, consisting of 4.6% 30-day mortality and 1.9% PND. Transient neurological dysfunction was found in 13.9% patients. Multiple logistic regression showed that stroke (OR=7.846, 95% CI: 2.737-22.489, p0.001), emergency (OR=2.198, 95% CI: 1.019-4.740, p=0.045), CPB time (OR=1.009, 95% CI: 1.004-1.014, p0.001), CABG (OR=2.613, 95% CI: 1.066-6.405, p=0.036) and packed red blood cells (OR=1.113, 95% CI: 1.038-1.193, p=0.003) were independent predictors of adverse outcome, and acute type A aortic dissection (OR=2.635, 95% CI: 1.535-4.524, p0.001), preoperative neurological deficits (OR=5.326, 95% CI: 1.529-18.548, p=0.009), CPB time (OR=1.004, 95% CI: 1.000-1.007, p=0.026) and cerebral low-flow time (OR=1.034, 95% CI: 1.003-1.066, p=0.033) were associated with TND.A history of stroke was a strong predictor of adverse outcome, and acute type A aortic dissection and preoperative neurological deficits had a high correlation with TND. The predictors identified in this study may help clinicians to optimise the risk evaluation and perioperative clinical management of patients undergoing aortic arch surgery to reduce morbidity and mortality.

In order to improve the structural and ferromagnetic property of BiFeO3, the effects of Ho3+ doping is systematically investigated. Pure BiFeO3 and Ho-doped BiFeO3 thin films are fabricated by sol-gel method, and the phase structure, morphology, crystalline structure, ferromagnetic are characterized by XRD, SEM, Raman spectra and VSM, respectively. The XRD patterns of the samples indicate that all the compounds crystallize in rhombohedral distorted perovskite structure with space group R3c and the Ho substitution can suppress the intrinsic formation of the miscellaneous phase. The SEM proves that along with the increasing of Ho concentration, the surface roughness of BiFeO3 is decreased due to the reduction of defects in the preparation. From the Raman spectroscopy, it is found that the peak intensity of 8 modes in Bi1-xHoxFeO3 are increased and the modes shift to higher wave number. Besides, the VSM results show that the ferromagnetic of the samples is enhanced with increasing of Ho concentration. When x=0.1, Ms is improved to be 4.8emu/g. The results can prove that the Ho3+ doping can reduce the volatilization of Bi3+, decrease the concentration of oxygen vacancies and improve the room-temperature ferromagnetic of BiFeO3.

To investigate the mechanism of rapamycin-induced apoptosis of chronic myelogenous leukemia cells.The chronic granulocytic leukemia K562 cells were divided into 3 groups: A, B and C group were treated with rapamycin of 10, 15 and 20 nmol/L, repectively for 24 h, while the K562 cells in control group were not treated with rapamycin. The effect of rapamycin on the proliferation of K562 cells was detected by MTT, and the effect of rapamycin on the apoptosis of K562 cells was detected by AnnexinV-FITC/PI double staining. The expression level of EZH2/Hedgehog signaling pathway genes in K562 cells was detected by RT-PCR, and Western blot was used to detect the levels of apoptotic protein and the related signaling pathway proteins in K562 cells.The MTT assay showed that the different concentration of rapamycin had obvious inhibitory effects on the cells, and the survival rate of cells in group C was 37.6%±3.4%, which was significantly lower than that of the other groups (P＜0.05). The apoptosis rate of cells in group C was 93.1%±8.1%, which was significantly higher than that of the other groups (P＜0.05). By Western blot, it was found that the relative expression levels of Caspase-3 and BAX protein in group C were 0.36 ± 0.04 and 0.39±0.06, respectively, which were significantly higher than those in other groups (P＜0.05), and the level of BCL-2 protein was 0.17±0.03, which was significantly lower than that of other groups (P＜0.05). By RT-PCR, it was found that the mRNA levels of EZH2 and Hedgehog genes in A, B and C groups were significantly lower than those in the control group (P＜0.05), but mRNA level of Ptch1 gene was significantly higher than that of the control (P＜0.05). By Western blot, it was found that the expression levels of EZH2 and Hedgehog protein in A, B and C groups were significantly lower than that in the control group (P＜0.05), but the level of Ptch1 protein was higher than that of the control (P＜0.05). The relative levels of EZH2 and Hedgehog protein in group C were 0.21 ±0.03 and 0.16±0.05 respectively, which were significantly lower than those in other groups (P＜0.05), and Ptch1 protein level were 0.46 ±0.06, significantly higher than that of other groups (P＜0.05).Rapamycin can inhibit the protein expression of EZH2 in leukemic cells, thus interfere with the activation of Hedgehog signaling pathway, promote the expression of apoptotic protein, reduce the level of anti apoptotic protein, and eventually induce apoptosis of leukemia cells.雷帕霉素通过EZH2/Hedgehog信号通路诱导慢性髓系白血病细胞凋亡.探讨雷帕霉素诱导慢性髓系白血病（CML）细胞凋亡的机制.对CML细胞K562用雷帕霉素10（A组）、15（B组）和20（C组） nmol/L分别处理24 h，对照组不加雷帕霉素。采用MTT法检测雷帕霉素对K562细胞增殖的影响, AnnexinV-FITC/PI 双染法检测雷帕霉素对K562细胞凋亡的影响, RT-PCR检测雷帕霉素对K562细胞EZH2/Hedgehog信号通路基因表达水平，Western blot检测雷帕霉素对K562细胞凋亡及相关信号通路蛋白表达水平.MTT法检测发现，不同浓度雷帕霉素对细胞增殖有明显抑制作用，其中C组的细胞存活率37.6%±3.4%，显著低于其它各组（P＜0.05）。通过AnnexinV-FITC/PI双染法检测发现，C组细胞的凋亡率为93.1%±8.1%，显著高于其它各组（P＜0.05）。Western blot检测发现，K562细胞在雷帕霉素作用后，C组的Caspase-3和BAX蛋白相对表达水平分别为0.36±0.04、0.39±0.06，显著高于其它各组（P＜0.05）；BCL-2 蛋白水平0.17±0.03，显著低于其它各组（P＜0.05）。RT-PCR检测发现，K562细胞在雷帕霉素作用后，EZH2与Hedgehog基因mRNA水平明显下降（P＜0.05），而Ptch1基因mRNA水平明显上升（P＜0.05）。Western blot检测发现，K562细胞在雷帕霉素作用后，其EZH2与Hedgehog蛋白表达水平下降，而Ptch1蛋白水平上升（P＜0.05）。C组的EZH2与Hedgehog蛋白相对水平分别为0.21±0.03、0.16±0.05，显著低于其它各组（P＜0.05）；Ptch1蛋白水平0.46±0.06，显著高于其它各组（P＜0.05）.雷帕霉素可抑制白血病细胞中EZH2蛋白表达，从而干扰Hedgehog信号通路的激活，并促进凋亡蛋白的表达，减少抗凋亡蛋白水平，最终诱导白血病细胞的凋亡.

In order to improve the performance of InGaAs/AlAsSb QCLs, the simulation of In 0.53 Ga 0.47 As/AlAs 0.56 Sb 0.44 QCLs on InP substrate are presented and analyzed. Based on the theory of carrier transition in an injector/3-level/extractor system, the conduction band diagram of InGaAs/AlAsSb QCLs is simulated and the effect of the inject layer thickness on the gain property and characteristic temperature are discussed. The results illustrate that the emitting wavelength λ blueshifts along with the increase of the inject layer thickness. And when the injection barrier width is 2.3 nm, the λ of In 0.53 Ga 0.47 As/AlAs 0.56 Sb 0.44 QCLs is around 4μm and the characteristic temperature is up to 140 K, which is in good agreement with experimental results. This work confirms the great potential of InGaAs/AlAsSb materials for the realization of efficient mid-infrared wavelength QCLs and provides a new way to design these devices.

Cyber-physical systems embed software into the physical world. They appear in a wide range of applications such as smart grids, robotics, and intelligent manufacturing. Cyber-physical systems have proved resistant to modeling due to their intrinsic complexity arising from the combination of physical and cyber components and the interaction between them. This study proposes a general framework for discovering cyber-physical systems directly from data. The framework involves the identification of physical systems as well as the inference of transition logics. It has been applied successfully to a number of real-world examples. The novel framework seeks to understand the underlying mechanism of cyber-physical systems as well as make predictions concerning their state trajectories based on the discovered models. Such information has been proven essential for the assessment of the performance of cyber-physical systems; it can potentially help debug in the implementation procedure and guide the redesign to achieve the required performance., Discovery of hybrid dynamical models for real-world cyber-physical systems remains a challenge. This paper proposes a general framework for automating mechanistic modeling of hybrid dynamical systems from observed data with low computational complexity and noise resilience.

The processing of Mongolian medicine,which is called " mort harl" in Mongolian language,refers to a traditional processing technology to " tame" some toxic,aggressive,ineffective or inconvenient Mongolian medicines,so as to make it " compliant" to clinical needs. It is the summary of long-term experience in drug preparation by Mongolian medicine experts,one of the bridges for the dialectical unity of Mongolian medicine,the essential content in evaluation of the clinical efficacy of Mongolian medicine and the study of Mongolian medicine modernization,and also the important soft power carrier of " intangible cultural heritage" and " grassland culture" in Inner Mongolia autonomous region. In this study,the processing history,purpose,crafts,mechanism,processing standards and quality standards of Mongolian medicine were explained,and some suggestions were proposed for the problems of the Mongolian medicine processing and development: focus on the basic theory of Mongolian medicine and the clinical experience of Mongolian medicine in the development of traditional Mongolian medicine processing; strengthen the literature research on the processing method of Mongolian medicine; establish comprehensive and systematic Mongolian medicine concocts standards and quality standards; enhance the research and development of special processing equipment and process quality control instruments for Mongolian medicine; and strengthen the training of professional technicians,the protection of copyright in Mongolian medicine processing,and scientific research on Mongolian medicine processing. In the inheritance of the tradition,the latest achievements of modern scientific development can be also absorbed to provide reference for the further development of traditional Mongolian medicine processing technology.

Although microRNAs (miRNAs) function as the important tumor gene regulators, they still confront with many challenges in systemic delivery. Here, the amphiphilic gemcitabine-oleic acid prodrugs (GOA) binding miRNAs with hydrogen bond are assembled into nanoparticles (GOA/miR NPs) through hydrophobic interaction via denaturation-annealing processes and nano-precipitation technique. The non-cationic GOA/miR NPs with an average size of ~150 nm and a zeta potential of ~ − 15 mV exhibit a stable encapsulation of miRNAs with non-sequence selectivity. Either miR-122 or miR-34a encapsulated in the GOA/miR NPs is efficiently delivered into HepG2 cells and significantly downregulate the expression levels of target gene after lysosome escape and pH-responsive disassembly. Moreover, in vivo experiments demonstrate that the GOA/miR-122 NPs exhibit higher tumor accumulation. Compared to GOA micelles, GOA/miR-122 NPs displayed stronger tumor inhibition (73% regression) after intravenous injection in nude mice xenografted with HCC, along with rapid clearance in normal liver tissues. Furthermore, there is no significant influence on biochemical indicators and immune factors during the systematic administration of GOA/miR-122 NPs. The non-cationic GOA/miR NPs engineered by hydrogen bond interaction and hydrophobic forces show the enhanced synergistic antitumor efficacy and good biosafety, which will provide a potential nanomedcine for HCC treatment.

In robotic assembly processes, detecting target pose is indispensable for robot manipulation algorithms. Such a tedious work hinders the further application of robot manipulation algorithms to real industrial processes. In this paper, a vision-based position/impedance control framework is proposed. Therein, the objective pose is firstly obtained by a motion capture system, where a kinematic equation is solved to Figure out the target assembly pose. Next the robot arm motion is approximated by an impedance model, in this way, the position/impedance control law of the robot is derived, which drives the robot to perform a compliant assembly manipulation. Finally, a memory stick assembly experiment is conducted on a 6-DOF robot arm equipped with a motion capture system and a force-torque sensor. Experiment shows the efficiency of the vision-based position/impedance hybrid controller in terms of autonomous positioning and compliant assembly. Due to its convenience and generality, the present controller can be expected to apply to more general industrial scenarios.

The consensus problem for the multi-agent system with high-order linear dynamics is considered, where the state information is exchanged under a time-invariant topology. The formulation of a final consensus value is given. Then a fully decentralized consensus algorithm is proposed, which allows each agent to reach the consensus value using only finite number of steps of its past state information. The numerical simulation verifies the effectiveness of the algorithm.

There has been tremendous progress in the studies on manufacture techniques of micro/nano-scale flexible electronic devices in recent years. Electrospinning is an important patterning method in flexible electronic production. Nevertheless, the electrospinning process involves highly nonlinearities, uncertainties, and external noise. Therefore, it is critical to stabilize the electrospinning fiber diameter in the manufacture process. In this paper, we establish a closed-loop control system with the pump flow rate as input and fiber diameter as output. We adopt Dynamic Fuzzy Neural Network (D-FNN) to approximate the electrospinning process and generate the real-time fuzzy rules with input data. Then we develop a type -2 fuzzy control law executed by the pump to tune the fiber diameter. We conduct extensive experiments to verify the performance of proposed type-2 fuzzy control law. The results show that under the proposed interval type -2 fuzzy controller, the system achieves stability and the output fiber diameter becomes stable and tunable. The proposed controller hugely improves the consistency and controllability of the flexible microelectronic components.

OBJECTIVE: To study the clinical effect and safety of different maintenance doses of caffeine citrate in the treatment of apnea in very low birth weight preterm infants. METHODS: A total of 78 very low birth weight preterm infants with primary apnea were enrolled who were admitted from January 2016 to January 2018. They were randomly divided into high-dose caffeine group with 38 children and low-dose caffeine group with 40 children. Both groups received a loading dose of 20 mg/kg caffeine citrate, and 24 hours later, the children in the high-dose caffeine group were given a maintenance dose of 10 mg/kg, and those in the low-dose caffeine group were given a maintenance dose of 5 mg/kg. The two groups were compared in terms of response rate and incidence rate of adverse events. RESULTS: The high-dose caffeine group had a significantly higher response rate than the low-dose caffeine group (71% vs 48%; P < 0.05). Compared with the low-dose caffeine group, the high-dose caffeine group had significantly shorter duration of apnea and time of caffeine treatment (P < 0.05). There were no significant differences between the two groups in length of hospital stay and incidence rates of tachycardia, feeding intolerance, bronchopulmonary dysplasia, necrotizing enterocolitis, and intracranial hemorrhage (P > 0.05). There was no significant difference in the mortality rate between the two groups (P > 0.05). CONCLUSIONS: Higher maintenance dose of caffeine citrate has a better clinical effect than lower maintenance dose of caffeine citrate in the treatment of apnea in very low birth weight preterm infants, without increasing the incidence rates of adverse drug reactions and serious complications in preterm infants.

Hepatitis E virus (HEV) RNA has been recently discovered in semen samples of Chinese infertile man with a remarkably high rate of 28.1% (52/185, table 1).1 All HEV isolates belong to HEV genotype 4 (HEV4), which is the dominant strain prevalent in China. This intriguing discovery has aroused our attention. In a recent response to the work done by Huang et al , researchers in Germany tested 87 semen samples collected from infertile men, but the HEV RNA positive rate is 0% (table 1).2 Germany is prevalent with HEV3, so the authors suggested that HEV genotype-specific or variant-specific pathophysiology may explain the contrary results. However, the two studies both have limitations to reach a more accurate conclusion. The size of patients included in both studies is relatively small, and …

Due to large charging power of the submarine cable, with existing control strategy of DFIG during low voltage ride through (LVRT), the offshore wind farm connected to the grid through long-distance submarine cables is prone to transient over-voltage, which may affect the transient stability of power system. In this paper, the equivalent model of DFIG is established by analyzing transient characteristics and LVRT control strategy of DFIG. Based on the simple power system transient stability analysis model with wind power integration, the equal area criterion is used to analyze the influence of the DFIG control strategy on transient stability of power system. Aiming at the overvoltage problem that may be faced after the LVRT of offshore wind farm due to the submarine cable capacitance effect, optimizing reactive power control strategy for offshore wind farm, the coordination transient voltage control strategy of DFIG and reactive power compensation device is proposed. The time domain simulation is carried out, and the results show that the proposed control strategy can effectively suppress transient overvoltage.

In the multi-robot collaborative manufacturing, such as the server motherboard assembly task in the 3C industry, the characteristic of the operating process and the uncertainty of the assembly environment make this problem difficult to be solved in an efficient way. This paper addresses the key points of this problem. Firstly, a series of end effectors for 3C assembly operation is designed. After analyzing precision and scope for different steps in the assembly process, the positioning systems with different precision and scope are designed and are chosen for better performance in different operations. Finally, compliant control is introduced in the inserting process where the positioning system does not perform well to further increase the success rate. Experiments illustrate the superiority of our ideas. Due to its convenience and generality, the present approach can be expected to apply to more general industrial scenarios.

A multi-unmanned surface vessel (USV) formation control system is established on a novel platform composed of three 1.2 meter-long hydraulic jet propulsion surface vessels, a differential GPS reference station, and inter-vessel Zigbee communication modules. The system is also equipped with an upper level collective multi-USV protocol and a lower level vessel dynamics controller. The system is capable of chasing and surrounding a target vessel. The results are supported by rigorous theoretical analysis in terms of asymptotical surrounding behavior and trajectory regulation. Extensive experiments are conducted to demonstrate the effectiveness and efficiency of the proposed hardware and software architectures., Comment: 8 pages, 6 figures

In order to improve the detection probability of day-time KHz satellite laser ranging, the laser beam monitoring system was proposed based on the technology of spectral filtering and image processing. By adjusting the exposure time and exposure number of CCD carried out at synchronous triggering mode, a high-quality image of laser backward scattering was obtained under the condition of strong day-time background noise and massive aerosols. When the time delay of CCD in laser beam monitoring system was set to 0ms, the exposure time was set to 60μs and exposure number was 1000 times, the laser beam tip image could be identified easily with the highest brightness and legible outlines. This proposed system could monitor and control the laser beam in daytime and help to adjust the optical path in real time, which will provide technical support for daytime KHz laser satellite ranging.

One new indole-type alkaloid

With the development of science and technology, the Internet of things technology has been gradually applied to various fields, it has become one of hot spot after the computer, the Internet and mobile communication technology. This paper focuses on the application research of Internet of things to oil pipeline leak detection. In general, oil pipelines are partially or completely buried under the ground, due to many reasons such as rust and breakage, leakage accident happens frequently. Aiming at this problem, this paper utilizes Internet of things technology to collect and process pressure signals, and detects the leakage by using negative pressure wave method to locate the leakage position, it is effective and exact.

Charge variants are the most commonly observed sources of heterogeneity in the routine manufacturing of monoclonal antibodies. To gain further insight into the structural foundation of charge heterogeneity and its influence on biological functions, an infliximab biosimilar HS626 from a biopharmaceutical facility was isolated by semipreparative cation exchange chromatography (CEX) to obtain fractions of acidic and basic charge variants and determine the main species. It was assessed again by CEX to ensure purities. Through a series of structural and physicochemical characterizations, we concluded that the acidic variants were caused by fragments, Met oxidation, Asn deamidation, higher levels of sialylation and galactosylation of N-linked glycans, and less high mannose. The basic variants resulted mainly from aggregates, fragments, and Met oxidation. Through further analysis of antigen binding affinity, cell death inhibitory activity, ADCC, and CDC, as well as FcRn, FcγRIIIa, and C1q affinity, we demonstrated that the charge heterogeneity did not affect biological functions. This research enhances the understanding of charge variants, which are usually effective components that should not be intentionally reduced unless biological functions are affected.