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As the fundamental energy storage components in electronic systems, dielectric capacitors with high power densities were demanded. In this work, the anti-ferroelectric Pb0.89La0.06Sr0.05(Zr0.95Ti0.05)O3 (PLSZT) ceramics and thin film capacitor were successfully fabricated by a solid-state reaction route and pulsed laser deposition method, respectively. The ferroelectric, dielectric, energy-storage properties, and temperature stability of anti-ferroelectric PLSZT capacitor were investigated in detail. By compared with the PLSZT ceramic (energy storage density is 1.29 J/cm3 with an efficiency of 78.7% under 75 kV/cm), the anti-ferroelectric PLSZT thin film capacitors exhibited the enhanced energy storage density of 52.6 J/cm3 with efficiency of 67.7% under an electric field as high as 2068.9 kV/cm, and the enhanced energy-storage temperature stabilities from room temperature (RT) to more than 200 °C were demonstrated, and the oxygen defects mechanism and size effect were discussed. Moreover, the fast charging (∼0.05 μs) and discharging (∼0.15 μs) time were certified for the anti-ferroelectric PLSZT film capacitor. These findings broaden the horizon for PLSZT anti-ferroelectrics in high energy storage properties and show promising for manufacturing pulse power capacitor.

An experimental study of the ion charge state distribution and mass-charge component of vacuum arc discharging with titanium-nickel alloy hydride by the time-of-flight method is carried out. The study shows that the charging states of titanium ion and nickel ion are 1+, 2+, and 3+. Besides, in the early stage of the discharging process (0–30 μs), the proportion of H + gradually increases with time and reaches a maximum ratio of 57% at 30 μs, the proportion of Ti n + and Ni n + (n = 1,2,3) gradually decreases with time and reaches a minimum ratio of 43% at 30 μs; In the later stage of the discharging process (30 μs-270 μs), the proportion of H + begins to decrease rapidly and remains unchanged at around 12% during the period spanning from 75 μs to 270 μs; the proportion of Ti n + and Ni n + (n = 1, 2, 3) gradually increases with time and remains around 88% from 75 μs to 270 μs.

For complex mineral compositions and ultra-fine grain embedded structure, beneficiation of iron from low-grade ore resources has been a realistic problem. In this work, an innovative technology named rapid but low-temperature direct reduction followed by magnetic separation was developed to process this kind of refractory iron ore. Ore-coal composite prepared by a typical low-grade iron ore (silica: 41.81%; iron: 31.24%) was reduced by lignite at 960 °C for 35 min, and crud iron powder assaying 83.10% of total iron can be obtained with recovery of 81.48% by subsequent magnetic separation based on laboratory tests. However, there is no precedent for an industrial reduction method to process either low-grade ore or ore-coal composites. Thus, a pilot scale rotary kiln (φ1.5 m × 15 m) reduction test was carried out for months to explore a possible approach for processing this type of iron ore. Reduced samples with a metallization ratio of 85.15% were obtained under stable operating conditions using this method. A post-mortem study was then carried out to better understand and optimize this new reduction process. The results demonstrated that the minerals evolution course during rotary kiln reduction can be summarized as follows: hematite was reduced to magnetite, wustite, and therefore partial quartz transformed to fayalite as materials were preheated within 15–11.5 m position → reduction occurred rapidly in 11.5–5.5 m zone, magnetite and wustite were reduced to iron, fayalite transformed to iron and amorphous silica → migration and growth of metallic iron particles in the length of 4.5–0 m. Rapid reduction at low temperature lessened the fayalite formation, creating favorable beneficiation conditions for iron element.

Cell-generated extracellular vesicles (EVs) are being engineered as biologically-inspired vehicles for targeted delivery of therapeutic agents to treat difficult-to-manage human diseases, including lysosomal storage disorders (LSDs). Engineered EVs offer distinct advantages for targeted delivery of therapeutics compared to existing synthetic and semi-synthetic nanoscale systems, for example with regard to their biocompatibility, circulation lifetime, efficiencies in delivery of drugs and biologics to target cells, and clearance from the body. Here, we review literature related to the design and preparation of EVs as therapeutic carriers for targeted delivery and therapy of drugs and biologics with a focus on LSDs. First, we introduce the basic pathophysiology of LDSs and summarize current approaches to diagnose and treat LSDs. Second, we provide specific details about EVs, including subtypes, biogenesis, biological properties and their potential to treat LSDs. Third, we review state-of-the-art approaches to engineer EVs for treatments of LSDs. Finally, we summarize explorative basic research and applied applications of engineered EVs for LSDs, and highlight current challenges, and identify new directions in developing EV-based therapies and their potential impact on clinical medicine.

To assess the energy operation level of various working groups (WGs) in reheating furnace, a novel approach for lean energy operation based on energy apporitonment model has been proposed in reheating furnace. This new approach mainly includes: i) The billet gas consumption (BGC) apportionment model; ii) The BGC equivalence value (BGCEV) model; iii) The BGC operation level evaluation model. A case study has demonstrated that: The average BGCEV (ABGCEV) of four WGs in the order of data size is: B Group (1.44 GJ/tons); C Group (1.40 GJ/tons); D Group (1.38 GJ/tons); A Group (1.37 GJ/tons). Then, the BGC operation level of four WGs is evaluated as: excellent grade (A Group and D Group); good grade (C Group); poor grade (B Group). The model accuracy analysis shows that this novel appraoch (Model 2) had higher accuracy than traditional calculation method (Model 1). Then, the ABGCEV standard deviation analysis results show that the ABGCEV fluctuation degree is the most improtant factor determining the BGC operation level of each WG. Therefore, how to improve operation stability is an improtant way to achieve lean energy operation of reheating furnace, such as theoretical training, simulation training, skill training etc.

For manufacturing systems, product quality and machine reliability are two key health indicators, which usually deteriorate as a result of machine deterioration. Maintenance can mitigate the machine deterioration and consequently improve product quality and machine reliability. In this context, we propose a quality and reliability oriented condition-based maintenance (CBM) policy for the serial multistage manufacturing systems. In the policy, the conditions of quality-related components are monitored to evaluate the quality loss of final products and the system failure rate, which are further compared with the corresponding thresholds to decide whether to trigger preventive maintenance (PM). When PM is triggered, a cost-based improvement factor is introduced to identify the importance ranking of PM groups and then determine a group of machines for PM. This factor is developed based on importance measure and jointly considers the improvement of quality and reliability and the reduction of maintenance costs. A multi-level CBM decision-making process is developed to evaluate the total cost over the planning horizon for decision optimization. The effectiveness and superior performance of the proposed CBM policy is demonstrated through a case study of a serial four-stage machining system producing shaft sleeves.

The electrocaloric effect (ECE) in gadolinium and tin ions doped lead lanthanum zirconate titanate ceramics was investigated. Five samples with different compositions and hence different relaxor behaviors and polarization properties were prepared via a conventional solid-state reaction process. The ECE was measured directly by a high resolution thermometer from 293 K to 423 K. The results show that the ECE is mainly determined by the number of polarization states and polar-correlation strength. Furthermore, the results reveal that the temperature variation of ECE around Curie temperature is associated with the generation rate, activation energy, size and freezing temperature of polar nanoregions. As a result, Sn doped PLZT composition exhibits the best ECE, i.e., a peak ΔT > 2 K obtained at 5 MV/m, and ΔT > 1.78 K achieved in the whole temperature range measured at the same field, which are very attractive for high performance ECE devices.

Overhead cranes, which have been extensively studied, are mostly simplified as single pendulums. However, in practice, the existence of lifting hook usually makes the crane present double-pendulum swing, i.e., hook swing with respect to the trolley and payload swing with respect to the hook. Therefore, a severe gap between theory and practice is generated. Due to this fact, lots of researchers are now working on the automation for double-pendulum overhead cranes (DPOC). However, with an extra unactuated degree of freedom, the control of DPOC is much more challenging than that of the simplified system due to its complicated dynamics, which is made even worse when considering payload hoisting/lowering and uncertain system parameters. To solve this problem, an enhanced-coupling adaptive controller is proposed for DPOC in this paper. Specifically, the payload hoisting/lowering motion is elaborately considered. Moreover, to improve the swing suppression performance, more swing information are incorporated into the construction of control inputs. Particularly, the uncertain payload mass is online estimated by a new adaption law ensuring precise identification, which further enhances the robustness of the proposed method. By utilizing Lyapunov techniques and LaSalle’s Invariance Theorem, the closed-loop system is proven to be asymptotically stable around the desired equilibria. Finally, convincing hardware experimental results are presented to demonstrate the efficiency and superior control performance of the proposed method.

An offshore ship-mounted crane consisting of a trolley, a wire, and a payload, is a typical nonlinear underactuated system, which suffers from unmatched disturbances mainly caused by sea waves and currents. Besides, unknown or uncertain parameters may cause vertical positioning errors or make accurate gravity compensation impossible, which may induce various risks during the transportation process. In terms of the aforementioned problems, this paper studies the adaptive robust tracking control problem for an offshore ship-mounted crane. In particular, a new adaptive robust coupling control approach, with adaptive laws included to deal with unknown parameters, and robust terms included to handle unknown disturbances, especially unmatched disturbances, is constructed in this paper, which achieves simultaneous load swing suppression and disturbances elimination. Without any approximation to the original nonlinear model, it is rigorously proven that the proposed method can ensure the stability of the overall crane system’s equilibrium point, as supported by Lyapunov techniques. Finally, some contrast simulations and experimental results are collected to verify the superior performance of the proposed controller.

In this work, the lead-free and BiFeO3 doping Na0.5Bi0.5TiO3-BaTiO3 thin films [(0.94-x)Na0.5Bi0.5TiO3-0.06BaTiO3-xBiFeO3 (NBT-6BT-xBFO), x = 0.00, 0.01, 0.03, 0.05 and 0.07] were deposited on Pt/Ti/SiO2/Si substrates by a sol-gel method. The enhanced ferroelectric properties and high energy-storage density have been achieved at 5% BiFeO3 substitution. Moreover, the 5% BiFeO3 doping Na0.5Bi0.5TiO3-BaTiO3 (0.89NBT-0.06BT-0.05BFO) thin-films exhibited a high dischargeable energy density (Wrecovered) of 42.9 J/cm3 with a corresponding energy-storage efficiency (η) of 65.7% under an electric field of 1720 kV/cm, and the high temperature stabilities with regard to their energy-storage properties over temperatures ranging from room temperature to 260 °C were demonstrated, and the charging and discharging characteristics demonstrate the faster microsecond discharge and large dielectric strength of the thin film capacitor. The results indicated that the 0.89NBT-0.06BT-0.05BFO thin-films might be promising environmentally friendly lead-free materials for energy-storage capacitor application.

Station reliability and product quality usually interact with each other stochastically in the multi-station manufacturing systems, which brings much trouble for the preventive maintenance (PM) scheduling of the system. In this paper, a station reliability evaluation method is developed firstly based on the introduced bidirectional interaction mechanism between station reliability and product quality, in which the focus is on the derivation of the failure rate of the stations. Then, a dynamic opportunistic PM (OM) policy is presented for the series multi-station systems with such quality integrated station reliability. The OM model is built up based on an extended cost saving method, and the optimal PM scheme of the system is obtained by maximizing the short-term cost savings which not only come from the stations conducting PM but also come from the downstream stations of those PM stations. Finally, a numerical example is given to illustrate how this PM scheduling approach works, and a numerical comparison on different OM policies is also given to show the effectiveness of the proposed OM policy under such interaction between station reliability and product quality.

Phosphotungstic acid (HPW) was immobilized on a sulphonic-acid-functionalized SBA-15 mesoporous molecular sieve through a one-step hydrothermal synthesis method, using non-ionic surfactant pluronic P123 as a structure-directing agent in acidic media, tetraethoxysilane (TEOS) as a silicon source and 3-trimethoxysilyl-1-propanethiol (MPTMS) with hydrogen peroxide (H2O2) oxidized to a sulfonic acid group. The obtained composite material HPW-SBA-15-SO3H has a high specific surface area, large pore volume and increased strong acidity. The effect of raw-material ratio on the catalyst was investigated. Catalysts that were prepared under optimal conditions of a molar ratio of (MPTMS)/ (MPTMS + TEOS) of 1:10, a molar ratio of (H2O2)/(MPTMS) of 18:1 and a mass ratio of (HPW)/(TEOS) of 1:10 exhibited an excellent catalytic activity in the esterification reaction of cyclohexene with formic acid. The cyclohexene conversion exceeded 86.7% and the cyclohexyl formate selectivity was 98.1% after 6 h at 353 K with a mole ratio of cyclohexene to formic acid of 1:3 and a catalyst dosage of 5.7% (w/w). The composite catalyst had a higher catalytic stability than the sulfonic-acid-functionalized SBA-15 and SBA-15-immobilized HPW individually. The cyclohexene conversion reached 72.0% even after reused four times. Fourier transform infrared and temperature-programmed desorption of ammonia revealed that a strong interaction existed between the sulfonic-acid group and the HPW, which prevented acid-active component of HPW and sulfonic-acid group loss from the carrier.

Researches on overhead cranes are mainly aimed at single-rope ones. However, to guarantee safety and increase the transportation efficiency, many overhead cranes tend to use more ropes to suspend the payload during the actual operation, which results in severe gap between theory and practice. The study on multi-rope cranes has achieved little progress in the past years, and no precise model has been proposed for such systems. So far, existing results for multi-rope cranes are usually based on linearizations or approximations, whose performance can be hardly guaranteed in many cases. Motivated to solve this problem, a dynamic model for multi-rope cranes is first set up in this paper by utilizing Lagrangian modeling method. Based on that, a nonlinear controller is further proposed, which incorporates more swing-related information into the control law, so as to enhance the robustness and swing suppression performance of the closed-loop system. The asymptotic stability of the desired equilibrium point is rigorously guaranteed by Lyapunov techniques and LaSalle’s invariance theorem. Finally, to demonstrate the feasibility and efficiency of the designed controller, hardware experimental results are provided as a convincing validation.

The past decades have seen increasing demands for the transportation capability of overhead cranes. In practice, as the cargoes grow larger and heavier, they often need to be cooperatively delivered by two cranes. However, even with wide application, the study of such dual overhead crane system (DOCS) still fails to receive enough attention from researchers. Until now, few results have been published for DOCS, and most of them present no rigorous analysis for the overall system dynamics. Motivated to solve these issues, a precise model is first set up for DOCS by utilizing the Lagrangian modeling method. Based on that, a nonlinear control strategy is further proposed, which elaborately considers the coordination between cranes. By utilizing Lyapunov techniques and LaSalle’s invariance theorem, the desired equilibrium point of the closed-loop system is proved to be asymptotically stable, without tuning to linearization or approximations. Finally, feasibility and efficiency of the proposed method are further validated by convincing hardware experimental results.

To reveal distribution of slab thermal efficiency (STE) and its bottlenecks, a slab region thermal efficiency (SRTE) model and an STE model were established based on the energy apportionment model of a reheating furnace in this paper. The bottleneck index of the slab thermal efficiency (BISTE), which could be used to assess the influence of SRTE on STE in a particular region, was proposed. First, the regional energy balance equation was listed based on reheating furnace region division. Next, the SRTE and STE models were established. Second, the bottleneck of slab thermal efficiency (BSTE) was achieved through a partial correlation analysis (PCA) of billet samples, which were obtained according to the difference between billet loading temperature and its residence time in the reheating furnace. Next, the BISTE was advanced to accurately determine the BSTE. Finally, several suggestions or measures, that could improve SRTE, were proposed. The case study has demonstrated the validation of these models, and the BISTE was 42% (Preheating), 19% (Heating II), 18% (Soaking), 11% (Heating I) and 10% (Preheating & Heating), respectively. Therefore, the preheating zone is the key region used to improve STE.

To master the fluctuation characteristic of billet gas consumption in different regions of reheating furnace, a system analysis method about fluctuation degree of billet region gas consumption (BRGC) is put forward in accordance with energy apportionment model. And this system analysis method mainly includes: (i) The space division of reheating furnace; (ii) The simplification of energy apportionment model in reheating furnace; (iii) The classification of billet samples; (iv) The establishment of BRGC standard deviation (BRGCSD) analysis model. A case study shows that (i) the BRGC fluctuates greatly in low temperature area, and fluctuates smoothly in high temperature area; (ii) The volatility degree of BRGC is intensified because of the lower loading temperature; (iii) It is very reasonable that the residence time of billets is controlled in (3,4] and (4,5] range, and the average fluctuation degree is about 0.01 and 0.012 respectively; (iv) The fluctuation of BRGC is amplified in some regions because of mixed charging. The analysis results show that some measures can reduce the fluctuation of BRGC, such as the stable operation of tiny positive pressure, the control of production rhythm, the improvement of billet loading temperature, the optimization of loading plan.

Barium zirconate titanate (Ba(ZrxTi1-x)O3) thick film ceramics were prepared using a tape-casting method. Their structures, morphologies, and electric properties were characterized using XRD, SEM and impedance analysis approaches, respectively. The electrocaloric effects (ECE), i.e., isothermal entropy changes and adiabatic temperature changes, were calculated using a Maxwell relation. It was confirmed by XRD and SEM that the obtained thick film ceramics are pure and dense perovskite structures. The dielectric analyses indicate that the Ba(ZrxTi1-x)O3 thick film ceramics show characteristics of transition from normal to relaxor ferroelectrics with the increasing Zr4+ ionic content. The polarization – electric field (P-E) hysteresis loops reveal larger polarizations and the ceramics can withstand an electric field as high as 12 MV/m. The adiabatic temperature changes ΔT calculated via the Maxwell relation and the polarization as a function of temperature, which is extracted from the P-E hysteresis loops measured at 12 MV m−1 are from 3.7 to 0.28 K with the increasing Zr4+ ionic content.

To achieve variations on billet gas consumption intensity (BGCI) of reheating furnace in different production states, a simplified BGCI apportionment model, which was based on the division of production states, was put forward in this paper. Firstly, production states were divided into four different modes according to the sequences of billet loading and unloading and billet number change in reheating furnace, namely, (i) normal production state (NPS), (ii) abnormal production state (APS), (iii) stop production state (SPS), which included preserving heat and waiting rolling state (PHWRS) and baking process state (BPS), (iv) transient production state (TPS), which included abnormal transient production state (ATPS) and stop transient production state (STPS). Secondly, a simplified BGCI apportionment model, which had better practicability, was established. Case study shown that the BGCI of APS or SPS was higher than that of NPS. And the longer the billet was in APS, the greater the BGCI was. Meanwhile, the initial temperature of billet and the repair time of reheating furnace had an important impact on BGCI. The results show that increasing the time of NPS is the most basic measurement in reducing BGCI. And elevation of initial temperature and reduction of the repair time are also effective measurement. And then, some suggestions and measures, which can achieve energy lean management of reheating furnace, are put forward.

This paper studies the automatic control problem of offshore boom cranes, which often work in harsh sea conditions. First, some novel composite signals are elaborately designed, which consist of both payload swing information and boom/rope positioning error. By utilizing the composite signals as feedback, the constructed nonlinear controller manages to react more efficiently to the uncertainties/disturbances, and hence achieves better overall control performance and stronger robustness. Particularly, the control gains are updated in real time according to the system dynamic response, so as to further improve the efficiency of the designed controller. Through rigorous mathematical deductions, it is proved that the system state variables converge to the desired values asymptotically. The conducted experiments show that the proposed method can accurately position the payload, while simultaneously suppressing its swing motion.

This paper proposes a novel opportunistic preventive maintenance (PM) scheduling methodology for the serial-parallel multistage manufacturing systems (SP-MMSs), where PM is performed to improve both the reliability and product quality. A SP-MMS has two essential characteristics: (i) the products can go through different process routes; (ii) the deterioration of a machine will not only affect the key product characteristics (KPCs) formed at the current stage but also propagate to downstream stages and then affect the KPCs formed there. Consequently, the propagation of machine deterioration along different routes will generate multiple streams of deterioration. This phenomenon is mathematically modeled to evaluate the quality of final products. The PM scheduling is based on the modeling of total maintenance cost including minimal repair cost, quality loss and PM-related costs. Firstly, a tentative PM schedule is made for each individual machine by minimizing the corresponding total maintenance cost. Secondly, the tentative PM schedules of all machines are further adjusted to obtain the optimal PM schedule for the system by jointly considering the economic dependence and control of final product quality. A case study shows that the methodology can ensure reasonably high reliability and final product quality for the system with a low total maintenance cost.

Overhead cranes, which are known as typical underactuated systems, are extensively studied in recent years. However, many existing methods for overhead cranes are developed based on a relatively ideal model, with little consideration for persistent external disturbances, unmodeled dynamics, uncertain system parameters and so on. Thus, their performance may badly degrade when it comes to practical applications, and this problem is made even worse when the system suffers from unmatched disturbances. To tackle this issue, a sliding mode control (SMC) method is proposed in this paper, which ensures satisfactory control performance even when the crane works under unfavorable conditions. The asymptotic stability of the desired equilibrium point is backed up with rigorous Lyapunov-based analysis. Furthermore, to alleviate the chattering problem inherent to SMC, a disturbance observer is further designed for overhead cranes to estimate and then eliminate the influence of the disturbances. Both simulation and hardware experimental results are provided to validate the efficiency and robustness of the proposed control strategy. To the best of our knowledge, this paper proposes the first method that can solve the control problem of overhead cranes suffering from both matched and unmatched disturbances, without tuning to linearizations or approximations.

This paper proposes an efficient nonlinear controller for an offshore boom crane, which is a combination of a learning strategy and an adaptive robust control method. An offshore boom crane is a kind of typical underactuated system which has less number of actuators than its degrees of freedom (DOFs), and it is also a sophisticated nonlinear system with strong-coupling characteristics, therefore, controller design for this kind of system becomes an extremely challenging task. Moreover, different from an overhead crane fixed on land, an offshore boom crane fixed on a vessel suffers from some peculiar disturbances of the attached ship’s multi-dimensional movement induced by waves and ocean currents, which implies that the motion of the ship can cause a tremendous effect on this system. Considering the periodic property of sea waves, this paper proposes an adaptive repetitive learning control strategy containing a learning law to deal with the aforementioned practical problems, as well as an adaptive law to handle the unknown system parameters. Specifically, different from traditional learning control strategy, the proposed control algorithm successfully addresses unknown periods of the periodic disturbances by introducing a period identifier into the control scheme. Meanwhile, the developed control strategy presents good robustness against ever-lasting disturbances and unknown parameters. The stability of the designed closed-loop system is guaranteed in the Lyapunov sense. Furthermore, some comparative experimental results are presented to demonstrate the efficiency of the proposed control method.

The amorphous Co 40 Fe 40 B 20 (CoFeB) films (5–200 nm in thickness) were grown on flexible polyethylene terephthalate (PET) substrates using the DC magnetron-sputtering method. The thickness dependence of structural and magnetic properties of flexible CoFeB thin films was investigated in detail. The in-plane uniaxial magnetic anisotropy induced by strain as a function of thickness was obtained in flexible CoFeB thin films, and a critical thickness of ~150 nm for in-plane magnetic anisotropy was observed. Moreover, the domains and the uniaxial anisotropy as a function of angular direction of applied magnetic field were characterized. The results show potential for designing CoFeB-based flexible spintronic devices in which the physical parameters could be tailored by controlling the thickness of the thin film.

To master the rules of energy consumption for different types of steel billet in a reheating furnace, this paper establishes an energy apportionment model based on the actual production performance and energy source data of a walking beam reheating furnace. And the cumulative energy segment is defined, and the time period, which spans from the billet loading time to the billet unloading time, is divided into k cumulative energy segments. The formula is discretized in integral form, and the energy allocation ratio is determined in every cumulative energy segment. A case study shows that the energy allocation is different due to differences in width of the billet, the production rhythm and steel grade. The higher the width and the slower the production rhythm are, the higher the energy allocation of the steel billet is, and vice versa. Meanwhile, the energy allocation is also different in individual steel grades. The results show that the energy allocation model has significant implications in the formulation of the steel billet loading plan, the control of the production rhythm and the energy assessment and can be used to achieve energy-lean operation.

Based on an open exactly solvable system coupled to an environment with nontrivial spectral density, we connect the features of quantum and classical correlations with some features of the environment, initial states of the system, and the presence of initial system–environment correlations. Some interesting features not revealed before are observed by changing the structure of environment, the initial states of system, and the presence of initial system–environment correlations. The main results are as follows. (1) Quantum correlations exhibit temporary freezing and permanent freezing even at high temperature of the environment, for which the necessary and sufficient conditions are given by three propositions. (2) Quantum correlations display a transition from temporary freezing to permanent freezing by changing the structure of environment. (3) Quantum correlations can be enhanced all the time, for which the condition is put forward. (4) The one-to-one dependency relationship between all kinds of dynamic behaviors of quantum correlations and the initial states of the system as well as environment structure is established. (5) In the presence of initial system–environment correlations, quantum correlations under local environment exhibit temporary multi-freezing phenomenon. While under global environment they oscillate, revive, and damp, an explanation for which is given.

While presenting many advantages in application, the loss of actuators also brings about great challenge to the control of underactuated systems. Specifically, the unactuated DOFs (degrees of freedom) cannot be directly controlled, instead, they have to be stabilized indirectly through appropriate regulation of actuated ones. As an unfortunate fact, the natural couplings between actuated and unactuated states are often relatively weak. Hence, in many practical cases, even the actuated states are well regulated, the performance of the unactuated states still fails to meet expectations. Such phenomenon is particularly obvious when the system faces various disturbances, since the unactuated states are more vulnerable to them and more difficult to be re-stabilized. To deal with the aforementioned issues, a nonlinear gain-adapting controller is proposed for a class of underactuated mechanical systems, which incorporates extra unactuated states-related information into the controller to enhance the state couplings. In this way, the closed-loop system reacts more appropriately and efficiently to the unactuated dynamics, which is expected to obtain improved transient performance and robustness. With a relatively concise structure, the proposed strategy imposes few requirements on the system configuration, which makes it more convenient for practical application. Theoretical analysis and experiment results are presented to demonstrate the performance of the proposed method.

With the rising concern of environmental pollution caused by fossil fuels, the energy efficiency becomes a key issue for the energy sensitive company in order to save the electricity cost and take responsibility for the sustainable development. Thus, an effective energy-aware operations management for the manufacturing plant is crucial to improve its competitiveness in the global market nowadays. We propose a mathematical model integrating three interrelated operational aspects including the production, maintenance and energy for the flow shops under Time-of-Use electricity tariff. A two-layer math-heuristic is devised to solve the model efficiently based on the decomposition of decision variables. In the outer layer, the jobs’ sequences and the buffer times are optimized using the metaheuristic based on genetic algorithm. In the inner layer, the maintenances’ positions and machines’ on/off are optimized using the exact method based on dynamic programming algorithm. Compared with CPLEX and traditional GA, the math-heuristic can get the near optimal solution with a small gap for the small-sized problems and perform well for the large-sized problems. The tradeoff between energy cost and makespan shows that more profit can be achieved using our model for the instance with a later production deadline. Finally, numerical experiments are also conducted to analyze the structure of the optimal solution in order to provide the managerial insights.

To optimize iron and steel production for the goal of energy intensity reduction, this paper systematically analyzed the flow characteristics of ferrite-flows and established an energy intensity production optimization model for production system in iron and steel industry. Production optimization model was calculated for a certain iron and steel company under five different ferrite-flows characters and structures. The results indicated that with the same product order, the energy intensity of the five optimized production schemes are decreased from the original scheme by 0.6%, 1.6%, 1.2%, 0.7% and 2.9%; calculated according to the crude steel production of the company in a month (October 2012, 1128 Kilo metric tons), energy saving of 4399 tce (ton coal equivalent), 111,505 tce, 8798 tce, 4963 tce and 20,980 tce, respectively, can be achieved. Through comparative analysis of the productions of various units under different schemes, it is discovered that the production optimization of the Ironmaking stage is the key and that the energy saving margin in optimized production of Steel-Rolling stage is limited. And then the energy saving technologies and measures, which favors production route re-optimizes, should be adopted in actual production process. In addition, the energy intensity reduces by 1.2 kgce/t, 0.4 kgce/t and 0.05 kgce/t while 1% increases of sinter ore grade, scrap and lump ore usage, respectively.

Surface display technology is an emerging key player in presenting functional proteins for targeted drug delivery and therapy. Although a number of technologies exist, a desirable mammalian surface display system is lacking. Exosomes are extracellular vesicles that facilitate cell-cell communication and can be engineered as nano-shuttles for cell-specific delivery. In this study, we report the development of a novel exosome surface display technology by exploiting mammalian cell secreted nano-vesicles and their trans-membrane protein tetraspanins. By constructing a set of fluorescent reporters for both the inner and outer surface display on exosomes at two selected sites of tetraspanins, we demonstrated the successful exosomal display via gene transfection and monitoring fluorescence in vivo. We subsequently validated our system by demonstrating the expected intracellular partitioning of reporter protein into sub-cellular compartments and secretion of exosomes from human HEK293 cells. Lastly, we established the stable engineered cells to harness the ability of this robust system for continuous production, secretion, and uptake of displayed exosomes with minimal impact on human cell biology. In sum, our work paved the way for potential applications of exosome, including exosome tracking and imaging, targeted drug delivery, as well as exosome-mediated vaccine and therapy.

Background There is inconsistent information about the clinical usefulness of circulating cell-free DNA (cfDNA) in plasma from clear cell renal cell cancer (RCC) patients. This is attributed to preanalytical, analytical, and clinical factors that were considered as far as possible in this study. Methods cfDNA was extracted from EDTA plasma of healthy people (n = 40), non-metastatic (n = 145) and metastatic (n = 84) RCC patients using the QIAamp Circulating Nucleic Acid Kit. Genomic and mitochondrial cfDNA concentrations were determined using qPCR of different cfDNA fragments (67–306 bp). Their diagnostic and prognostic potential was estimated using receiver operating characteristics (ROC) and Cox regression analyses. Results The 67 bp and 180 bp genomic cfDNA fragments did not differ between the three study groups while the 306 bp fragment was lower in RCC patients than in controls. The mitochondrial cfDNA was higher in metastatic than in non-metastatic patients and controls. The cfDNA integrity indices decreased from controls to metastatic patients. Models built by logistic regression and Cox regression resulted in area under the ROC curves > 0.75 and concordance indices of > 0.800 in predicting recurrence-free survival and overall survival. Conclusion The study suggests that combinations of cfDNA markers have promising diagnostic and prognostic potential in RCC patients and are worth for further validation in future prospective multicenter studies.

Display Omitted A joint model of preventive maintenance and quality improvement is developed.The joint model can achieve a superior economic performance in general case.Benefits can be created by integrating quality improvement into maintenance decision.Created benefits can be huge when quality-related components degrade rapidly.Created benefits can be huge when quality deviations cause big economic loss. For a deteriorating single-machine manufacturing system, preventive maintenance (PM) is an effective way to improve the machine reliability and product quality. In conventional PM models, however, quality improvement has been seldom considered, which may lead to loss of economic benefits. In this paper, a joint model is proposed, in which quality improvement is integrated into PM decision-making. In the proposed model, process variables affecting product quality are identified, among which adjustable process variables are measures of the degradation states of quality-related components of the machine. Based on the response model, a process model is developed to quantitatively describe the impact of process variables on product quality. An integrated reliability model is built for the machine based on the proportional hazard model considering the effects of the degradation states of quality-related components on machine reliability. Quality loss is incorporated into the total cost, which is minimized to obtain the optimal PM schedule. A case study is conducted to illustrate the effectiveness of the joint model. It shows that the joint model can achieve a superior economic performance to the conventional PM model in general case. Economic benefits can be created by integrating quality improvement into PM decision-making.

Many tropical and subtropical Impatiens species possess conspicuously long and narrow spurs and have been assigned to the butterfly pollination syndrome in investigations of floral evolution of this genus. However, this contradicts some previous studies documenting abundant hawkmoth visitors rather than butterflies. In this study, we explored the pollination ecology of Impatiens macrovexilla, a long-spurred species in Asia. We investigated a series of floral traits, tested the breeding system and contributions of different floral visitors to reproductive success, observed floral visitors and compared the spur length with the proboscis length of the nectar-collecting floral visitors. I. macrovexilla shows floral traits that cannot clearly be associated with a certain group of long-proboscid insects. Results showed that the species was visited by large nectar-collecting bees, diurnal hawkmoths, small pollen-collecting insects and rarely butterflies at different sites and in different years. Pollination treatments indicated that I. macrovexilla is self-compatible (Self-Incompatibility Index = 0.02) but completely relies on floral visitors for pollination. A treatment which excluded hawkmoths but permitted pollen-collecting insects to visit flowers revealed that diurnal hawkmoths contributed considerably to reproductive success of this species but that pollen-collecting insects acted as pollen thieves. Large bees firmly contacted anthers and stigmas when visiting flowers so probably also act as pollinators. The proboscises of large bees were shorter than half of the spur of I. macrovexilla in length, suggesting that they could only access the nectar accumulated near the mouth of the spur. However, hawkmoths can access most or all of the nectar because their proboscides match the length of the floral spur. Thus, the long nectar spur presumably reflects adaptation to diurnal hawkmoths. Using evidence from multiple lines of investigation, our study is the first to confirm the role of diurnal hawkmoths as pollinators in Impatiens.

Luciferase assay has become an increasingly important technique to monitor a wide range of biological processes. However, the mainstay protocols require a luminometer to acquire and process the data, therefore limiting its application to specialized research labs. To overcome this limitation, we have developed an alternative protocol that utilizes a commonly available cooled charge-coupled device (CCCD), instead of a luminometer for data acquiring and processing. By measuring activities of different luciferases, we characterized their substrate specificity, assay linearity, signal-to-noise levels, and fold-changes via CCCD. Next, we defined the assay parameters that are critical for appropriate use of CCCD for different luciferases. To demonstrate the usefulness in cultured mammalian cells, we conducted a case study to examine NFκB gene activation in response to inflammatory signals in human embryonic kidney cells (HEK293 cells). We found that data collected by CCCD camera was equivalent to those acquired by luminometer, thus validating the assay protocol. In comparison, The CCCD-based protocol is readily amenable to live-cell and high-throughput applications, offering fast simultaneous data acquisition and visual and quantitative data presentation. In conclusion, the CCCD-based protocol provides a useful alternative for monitoring luciferase reporters. The wide availability of CCCD will enable more researchers to use luciferases to monitor and quantify biological processes.

The oxidation behavior of SiC–SiBCN ceramics was studied at temperature range of 1200–1500 °C in air atmosphere. Amorphous SiBCN derived from a polyborosilazane precursor was used to prepare SiC–SiBCN composite ceramics. XRD and SEM were employed to analyze the phase composition and microstructure after oxidation experiments. The oxidation kinetics was studied by measuring the thickness of oxide layers. The values of the oxide layer thickness were found to fit a typical parabolic kinetics. The activation energy of the oxidation was also calculated from the rate constants of the different temperatures according to Arrhenius equation.

SiC ceramics were densified with 10 wt.% polymer-derived SiBCN additives by hot-pressing under a load of 40 MPa at 1850 °C for 90 min in a vacuum environment. Polyborosilazane was chosen as the SiBCN precursor and pyrolyzed at 1000 °C before use. The obvious densification process began at about 1700 °C during the sintering. The densification mechanism was different from the SiC ceramics densified by traditional sintering aids. When the temperature was above 1700 °C, particle rearrangement was accelerated because deformation and/or viscous flow of the SiBCN occurred under the external pressure. This procedure resulted in rapid increase of density. After particle rearrangement, B and C elements and nano SiC grains separating out from the SiBCN material led to SiC grain growth and further densification. The bending strength and Vickers hardness of the product were 562±36 MPa and 22.5 GPa at room temperature.

Despite their fundamental importance, the dynamics of signaling pathways in living cells remain challenging to study, due to a lack of non-invasive tools for temporal assessment of signal transduction in desired cell models. Here we report a dual-reporter strategy that enables researchers to monitor signal transduction in mammalian cells in real-time, both temporally and quantitatively. This is achieved by co-expressing green fluorescent protein and firefly luciferase in response to signaling stimuli. To display the versatility of this approach, we constructed and assessed eight unique signaling pathway reporters. We further validated the system by establishing stable NF-κB pathway reporter cell lines. Using these stable cell lines, we monitored the activity of NF-κB-mediated inflammatory pathway in real-time, both visually and quantitatively. Live visualization has the power to reveal individual cell responses and is compatible with single cell analysis, In addition, we provide evidence that this system is readily amenable to a high-throughput format. Together, our findings demonstrate the potential of the dual reporter system, which significantly improves the capacity to study signal transduction pathways in mammalian cells.

Transcription activator-like effectors (TALEs) are a class of transcription factors that are readily programmable to regulate gene expression. Despite their growing popularity, little is known about binding site parameters that influence TALE-mediated gene activation in mammalian cells. We demonstrate that TALE activators modulate gene expression in mammalian cells in a position- and strand-dependent manner. To study the effects of binding site location, we engineered TALEs customized to recognize specific DNA sequences located in either the promoter or the transcribed region of reporter genes. We found that TALE activators robustly activated reporter genes when their binding sites were located within the promoter region. In contrast, TALE activators inhibited the expression of reporter genes when their binding sites were located on the sense strand of the transcribed region. Notably, this repression was independent of the effector domain utilized, suggesting a simple blockage mechanism. We conclude that TALE activators in mammalian cells regulate genes in a position- and strand-dependent manner that is substantially different from gene activation by native TALEs in plants. These findings have implications for optimizing the design of custom TALEs for genetic manipulation in mammalian cells.

Aims To assess efficacy, safety, and tolerability of NGX-4010, capsaicin 8% patch, in patients with peripheral neuropathic pain. Methods This open-label, uncontrolled, 12-week study enrolled 25 patients with postherpetic neuralgia (PHN), one with HIV-distal sensory polyneuropathy, and 91 with painful diabetic neuropathy (PDN). Patients received pre-treatment with one of three 4% lidocaine topical anesthetics (L.M.X.4 1 1L.M.X.4 is a registered trade name of Ferndale Laboratories, Inc., Ferndale, MI, USA., Topicaine Gel 2 2Topicaine is a registered trade name of Estela Basso, Jupiter, FL, USA., or Betacaine Enhanced Gel 4 3 3Betacaine is a cancelled registered trade name of Tiberius, Inc., Tampa, FL, USA.) followed by a single 60- or 90-min NGX-4010 application. The primary efficacy variable was the percentage change in Numeric Pain Rating Scale scores from baseline to Weeks 2–12. Adverse events (AEs), laboratory parameters, vital signs, neurosensory examinations, dermal assessments, treatment-related pain scores, and medication use for treatment-related pain were collected. Results PDN and PHN patients achieved a 31% and 28% mean pain decrease from baseline during Weeks 2–12, respectively, and 47% and 44%, respectively, were responders (≥30% pain decrease). Mild or moderate treatment-site-related burning and pain were the most common AEs and there was no evidence of impaired neurosensory function. Conclusions NGX-4010 in conjunction with any of the three topical anesthetics tested was generally safe and well tolerated and reduced pain over a 12-week period in patients with PDN and PHN.

Phospholipids are required for epidermal lamellar body formation. Glycerol 3-phosphate acyltransferases (GPATs) catalyze the initial step in the biosynthesis of glycerolipids. Little is known about the expression and regulation of GPATs in epidermis/keratinocytes. Here, we demonstrate that GPAT 1, 3, and 4 are expressed in epidermis/keratinocytes, whereas GPAT2 is not detected. In mouse epidermis, GPAT 3 and 4 are mainly localized to the upper layers whereas GPAT1 is found in both the upper and lower layers. GPAT1 and 3 mRNA increase during fetal rat epidermal development. No change in GPAT expression was observed in adult mice following acute permeability barrier disruption. Calcium-induced human keratinocyte differentiation increased GPAT3 mRNA whereas both GPAT1 and 4 mRNA levels decreased. In parallel, total GPAT activity increased 2-fold in differentiated keratinocytes attributable to an increase in N-ethylmaleimide (NEM) sensitive GPAT activity localized to microsomes with little change in NEM resistant activity, consistent with an increase in GPAT3. Furthermore, PPARγ or PPARδ activators increased GPAT3 mRNA, microsomal GPAT activity, and glycerol lipid synthesis without affecting the expression of GPAT1 or 4. Finally, both PPARγ and PPARδ activators increased GPAT3 mRNA via increasing its transcription. Thus, multiple isoforms of GPAT are expressed and differentially regulated in epidermis/keratinocytes.

ABCG1, a member of the ATP binding cassette superfamily, facilitates the efflux of cholesterol from cells to HDL. In this study, we demonstrate that ABCG1 is expressed in cultured human keratinocytes and murine epidermis, and induced during keratinocyte differentiation, with increased levels in the outer epidermis. ABCG1 is regulated by liver X receptor (LXR) and peroxisome proliferator-activated receptor-δ (PPAR-δ) activators, cellular sterol levels, and acute barrier disruption. Both LXR and PPAR-δ activators markedly stimulate ABCG1 expression in a dose- and time-dependent fashion. PPAR-γ activators also increase ABCG1 expression, but to a lesser degree. In contrast, activators of PPAR-α, retinoic acid receptor, retinoid X receptor, and vitamin D receptor do not alter ABCG1 expression. In response to increased intracellular sterol levels, ABCG1 expression increases, whereas inhibition of cholesterol biosynthesis decreases ABCG1 expression. In vivo, ABCG1 is stimulated 3–6 h after acute barrier disruption by either tape stripping or acetone treatment, an increase that can be inhibited by occlusion, suggesting a potential role of ABCG1 in permeability barrier homeostasis. Although Abcg1-null mice display normal epidermal permeability barrier function and gross morphology, abnormal lamellar body (LB) contents and secretion leading to impaired lamellar bilayer formation could be demonstrated by electron microscopy, indicating a potential role of ABCG1 in normal LB formation and secretion.

Global synchronization of directed networks with switching topologies is investigated. It is found that if there exists at least one directed spanning tree in the network with the fixed time-average topology and the time-average topology is achieved sufficiently fast, the network will reach global synchronization for appreciate coupling strength. Furthermore, this appreciate coupling strength may be obtained by local adaptive approach. A sufficient condition about the global synchronization is given. Numerical simulations verify the effectiveness of the adaptive strategy.

Genetic predisposition may be underlying the prevalence of acquired atrial fibrillation (AF). We investigated the association between polymorphism in angiotensinogen (AGT) and angiotensin-converting enzyme gene and risk of acquired AF in a pair-matched case-control study conducted in Chinese Hans. We selected 9 single nucleotide polymorphisms (SNPs) in the AGT gene and 3 SNPs in the angiotensin-converting enzyme gene using a tagging-SNP strategy. We observed significant association between tagging-SNP rs699 (M235T), located in exon 2 of the AGT gene, and AF. The AA genotype of rs699 increased the risk of AF by 70% (95% confidence interval, 1.01-2.85; P = .044) under a recessive model (AA vs AG + GG). The significance remained after controlling for covariates age, smoking, body mass index, hypertension, diabetes, and left atrial dimension, with an increased risk of AF by 90% (95% confidence interval, 1.04-3.46; P = .036). We provide evidence that polymorphism in AGT gene may confer predisposition to acquired atrial fibrillation in Chinese Hans.

Many networks are made up of a few groups, with nodes in the same group having the same kind of function. In this work, the problem of controlling a complex dynamical network to attain an inhomogeneous equilibrium point is investigated, which means that nodes in the same group achieve the same equilibrium point as an isolated node, while different groups correspond to different equilibrium points. An open-loop constant control approach is first proposed to obtain the inhomogeneous equilibrium point of the network. Then, the feedback pinning control approach is applied to make the inhomogeneous equilibrium point asymptotically stable.

The goal of epidermal ontogenesis is to form a stratum corneum (SC), which is required for post-natal permeability barrier function. The regulation of epidermal ontogenesis is poorly understood, but nuclear hormone receptors have been shown to have an important function. As peroxisome proliferator-activated receptor-delta (PPARdelta) is very abundant in fetal epidermis and PPARdelta activation stimulates differentiation and permeability barrier formation in adults, we hypothesized that PPARdelta might regulate epidermal ontogenesis. Treatment of fetal rat explants with the PPARdelta ligand, GW 610742X, accelerates permeability barrier development, evidenced by a decrease in transepidermal water loss and an enhanced outside-in barrier function, attributable to the presence of more mature lamellar membranes in the SC and enhanced expression of loricrin and involucrin. Similarly, the intra-amniotic administration of GW 610742X also accelerates the formation of the SC and permeability barrier development. Finally, in PPARdelta-deficient mice the formation of the SC and the expression of differentiation-related proteins were delayed on days 16.5 and 17.5 of gestation. However, at later stages (day 18.5 and after birth), there were no differences between wild-type- and PPARdelta-deficient mice, indicating only a transient delay in epidermal ontogenesis. These studies show that PPARdelta has a role in SC formation and permeability barrier development.

The acute phase response is characterized by elevations in serum triglyceride levels due to both an increase in hepatic VLDL production and a delay in the clearance of triglyceride rich lipoproteins secondary to a decrease in lipoprotein lipase (LPL) activity. Recently there has been a marked increase in our understanding of factors that regulate LPL activity. GPIHBP1 facilitates the interaction of LPL and lipoproteins thereby allowing lipolysis to occur. Angiopoietin like proteins (ANGPTL) 3 and 4 inhibit LPL activity. In the present study, treatment of mice with LPS, an activator of TLR4 and a model of Gram-negative infections, did not alter the expression of GPIHBP1 in heart or adipose tissue. However, LPS decreased the expression of ANGPTL3 in liver and increased the expression of ANGPTL4 in heart, muscle, and adipose tissue. Serum ANGPTL4 protein levels were markedly increased at 8 and 16h following LPS treatment. Administration of zymosan, an activator of TLR2 and a model of fungal infections, also increased serum ANGPTL4 protein and mRNA levels in liver, heart, muscle, and adipose tissue. Finally, treatment of 3T3-L1 adipocytes with LPS or cytokines (TNF alpha, IL-1 beta, and interferon gamma) stimulated ANGPTL4 expression. These studies demonstrate that ANGPTL4 is a positive acute phase protein and the increase in ANGPTL4 could contribute to the hypertriglyceridemia that characteristically occurs during the acute phase response by inhibiting LPL activity.