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The liver of poultry is the primary site of lipid synthesis. The excessive production of lipids accumulates in liver tissues causing lipid metabolism disorders, which result in fatty liver disease and have a transgenerational effect of acquired phenotypes. However, its specific mechanisms have not yet been fully understood. In this study, the differentially expressed miR-375 as well as its target gene

As a piece of key equipment in the power system, GIS will cause great losses when it fails. Partial discharge detection technology is an important technic aims to evaluate the degradation status of GIS equipment insulation. Among them, the UHF method has been widely used to detect GIS partial discharge due to its superior anti-interference performance, but the partial discharge mechanism is more complicated and is affected by many factors such as operating voltage and load. Sometimes, the fault may develop quickly. Operation and maintenance personnel cannot resolve the fault in time, and this situation can be effectively solved by predicting the monitoring data of partial discharge. Although it is difficult to predict the long-term slow variability of partial discharges of internal devices in GIS, the detection of short-term variability discharge status is relatively stable. In this paper, an auto-regressive and moving average (ARMA) model is established for the extracted feature quantities in partial discharges in GIS. It can well predict the discharge trend in the few minutes or hours before the failure, which has good application value.

In high voltage power system, with the gradual increment of SF 6 gas closed-end insulation composite appliance, the application of Gas insulated switchgear (GIS) becomes more and more widely accepted based on its high reliability, less maintenance, long maintenance cycle, and low failure rate (only 20% ∼40% of conventional equipment). However, the GIS has its inherent shortcomings, as a result of the SF6 gas leakage, external water infiltration, the conductive impurities as well as insulator aging factors, such as internal flashover. To this end, this paper designs a rail-type inspection robot for GIS substation. First, it analyzes the background of high voltage substation and GIS. Secondly, considering the distribution of GIS and the task of substation inspection, the paper gives the key components of rail-type inspection robot, such as straight walking components, turning and changing track component, partial discharge (PD) detection component. Thirdly, it proposes that the architecture of rail type inspection robot system is a network distributed, which includes three parts: the background layer, communication layer and terminal layer. In addition, it discusses in detail the motion control method of inspection, especially positioning control. Then it explains the software and hardware structure of the motion control system: Radio frequency identification (RFID) is used for motion positioning of inspection robots; the background layer controls the motion of the inspection robot and uses the background software to analyze the detection data. Finally, the paper proves that the inspection robot has good balance, flexible turning, and a large inspection range. The robot can completely inspect work well instead of staff.

To guarantee the stability and reliability of the multi-area interconnected power system under faults occur in communication system, this paper presents a fault diagnosis strategy based on interval observer for automatic generation control in power system. Interval observer for fault diagnosis is firstly introduced in order to detect the faults occur in communication system in different control areas. Then, the residual errors that can be used for detecting the fault are constructed by using the outputs of interval observers and those of system. Thus, the problems of fault detection based on interval observer are resolved. Finally, the simulation experiment by applying different faults in a three-areas interconnected power system is operated, and the simulation results prove the correctness and the effectiveness of the proposed method.

Bridge crane system is widely used in production and life. Even so, we still have a lot of problems to solve on it, such as trajectory planning for the large vehicle and small vehicle and anti-swing of the hoist. However, the anti-swing problem of the bridge crane system is an issue of great value. A sliding mode control method is designed to solve this problem. Because of the characteristic that the bridge crane system is an under-actuated system, it is modeled on Lagrangian dynamics. The effect of the ordinary sliding mode control method for under-actuated systems is no longer satisfactory. A hierarchical sliding mode control is used instead of the ordinary sliding mode control. For under-actuated systems, the basic idea of the hierarchical sliding mode control method is to separate the driving part and under-acting part of the system into different subsystems. In this control method, the slip surface is divided into two layers. The first layer of slip surface includes two parts: one is the displacement error sub-sliding surface of vehicle, and the other is the suspended swing error sub-sliding surface. The second layer is the total slip surface. It contains two sub-sliding surfaces in the direction of the vehicle. The equivalent input term in the sense of Filippov is obtained according to the sliding mode surface of the first layer, and the switching control function term is obtained from the sliding mode surface of the second layer using the Lyapunov feedback function design method. The total system input can be got by combining the equivalent input term and the switching control function term. The simulation experiment by using the simulation module of Matlab is operated, and the simulation results prove the method has good control effect and robustness.

With the development of the scale of the power grid, Relay protection has gradually become an important part of ensuring the smooth and safe operation of power system while Pilot protection has also gradually become an important development direction of high-voltage line protection in the process of Relay protection development. Based on the research and comparison to the existing methods of current comparison pilot protection, direction comparison pilot protection and distance comparison pilot protection. In this paper, a protection method based on the characteristic of fault component of current at both ends of the circuit is proposed to overcome the disadvantage of the current differential protection scheme which is easily affected by the load current and the transition resistance, and the protection method is adopted which based on the instantaneous value of current fault component. In order to verify the rationality of the method which is proposed, an appropriate simulation model is designed, a simulation system is established, and various possible situations in the power system are simulated by using the simulation system. Simulation shows that the judgment based on the value of the fault current as a protective action has the following advantages: Firstly, the calculation is simple which only compares and judges the size of the fault component without real mathematical operations; Secondly, this method has lower requirements for the communication channel, which only a very simple signal needs to be transmitted when a possible fault is found; In addition, the action is fast, and only the instantaneous value of the fault component of the current can determine whether the action is or not.; Finally, the action is reliable, the judgment of this method is very reliable and will not refuse to acting. At the same time, it can avoid the influence of harmonics and other factors by adjusting the action threshold, which ensures that the protection will not malfunction.

The safe operation of power transmission lines is the key technology to guarantee safeness and reliability of the power supply. But traditional inspection system has some problems such as poor adaptability, insufficient intelligent level and unstable signal. Therefore, in this paper, a kind of intelligent inspection system for power transmission lines combining BeiDou positioning and artificial intelligence is proposed based on ground line mobile robot platform. In this system, a field path navigation model is established based on Amap, and intelligent algorithms are used to plan the inspection route, and a graphical inspection function model is set up. Multi-point and multi-layer connection are established and defects database for the risk information are improved gradually through intelligent analysis. This system is significant to improve inspection efficiency and reduce fault handling time.

The 500kV overhead transmission line induction power supply technology can provide stable and reliable power for high-voltage line online equipment and inspection robots. Since the magnitude of the induced current induced in the ground wire is small, in order to make full use of the induced energy, the principle of impedance matching can be used according to the topology of the circuit to increase the power drawn from the induction. This article focuses on the operating environment of 500kV overhead transmission lines, and designs a typical induction power circuit structure consisting of a power coil, a rectifier filter circuit, and a two-level DC-DC converter circuit. Based on this simplified equivalent circuit model, this paper designs the controller of the two-level DC-DC converter circuit, and realizes the maximum power point tracking (MPPT) control of inductive power draw by changing its duty cycle. Finally, the simulation results on the Simulink platform verify the accuracy of the simplified circuit model and the effectiveness of the maximum power point tracking control method.

As a kind of partial differential system, the string system has a great application space in fields of aerospace and transportation, such as high-altitude electrical equipment measurement and maintenance using an unmanned aircraft. At same time, vibration suppression of string system has received great concern in engineering. In this paper, a underactuated string system with boundary disturbance based on unmanned aircraft hoisting payload is studied. System dynamic is modeled by Hamiltonian principle. The control objective in this paper are to move the payload to the desired position through the movement of the unmanned aircraft, and the vibration of the cable can be quickly eliminated. An improved boundary control law is presented in this paper, and the asymptotic stability of the system is proved by Lyapunov theory. The effectiveness of the method in this paper is verified by numerical simulation.

High-resolution Fourier-transform spectra of water samples enriched by deuterium and oxygen-18 at room temperature are analyzed in the range 969–2148 cm−1. Line positions of about 2470 transitions up to Jmax = 22 and Ka max = 12 of the ν2 bands of the HD18O and D 2 18 O molecules are reported. This has allowed the determination of extended sets of rotational energies of the (0 0 0) and (0 1 0) vibrational states for both molecules. The generation function model of an effective rotational Hamiltonian was used in the data reduction to account for the strong centrifugal distortion of the rotational levels. Values of effective Hamiltonian parameters have been determined. The RMS standard deviations of the least-squares fits of the energy levels were 2.4 × 10−4 cm−1 for 293 energy levels of the ground state and 3.2 × 10−4 cm−1 for 281 energy levels of the (010) state of D 2 18 O , and 2.6 × 10−4 cm−1 for 227 energy levels of the ground state and 4.2 × 10−4 cm−1 for 246 energy levels of the (0 1 0) state of HD18O. Comparisons of obtained data with the theoretical predictions as well as with other observations are presented.

SummaryThe bolus intravenous infusion of factor Xa in combination with phosphatidylcholine/phosphatidylserine (PCPS) vesicles, at a dose of 2.6 × 10-11 moles and 4.0 × 10-8 moles/kg body weight respectively, has previously been shown to correct the bleeding diathesis of haemophilic (factor VIII deficient) dogs (Br J Haematol 1988; 69: 491-7). The cuticle bleeding time (CBT) was used as the test to evaluate objectively this response. Transmission electron microscopy was performed to document the evolution of haemostatic plugs forming in the vascular bed of the injured cuticles of both normal and factor VIII deficient dogs with and without treatment with factor Xa/PCPS. The dosage previously shown to normalize the CBT in haemophilic and significantly shorten it in normal animals was used. Subjective and objective observations, using morphometric techniques, were made over a period of 25 min following injury induction. The administration of factor Xa/PCPS was associated with complete and sustained normalization of haemostatic plug development in the haemophiliacs including platelet recruitment, activation and compaction and subsequently fibrinous transformation. In the case of the normals, platelet activation, etc., was exaggerated and fibrinous transformation appeared to be accelerated. The haemostatic plugs forming in the treated haemophiliacs were indistinguishable from those forming in the normals and significantly different, with regard to all parameters measured, from the morphological appearances noted in the untreated haemophiliacs. These data suggest that the correction of the haemostatic defect previously observed results from the normalization of haemostatic plug formation and that this is sustained despite the promotion of systemic fibrinolysis that is also known to occur.

The fifth intron of the human antithrombin gene (AT3) of chromosome 1q23 contains a highly polymorphic short tandem repeat based on the trinucleotide repeat (ATT). Alleles range in size from (ATT)5 to (ATT)18, and can be typed using the polymerase chain reaction. Here we report allele frequency population data for Caucasians, Blacks and Southeast Asians. Statistical analyses demonstrate consistency with Hardy-Weinberg equilibrium for all three databases, and that the allele frequencies of all three population groups are significantly different from each other. This locus reveals 76% to 87% heterozygosity and therefore may be useful for forensic identity testing and paternity determination.