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The northward shift of Pyropia yezoensis aquaculture required the breeding of germplasms with tolerance to the oxidative stress due to the high light conditions of the North Yellow Sea area. The MPV17/PMP22 family proteins were identified as a molecule related to reactive oxygen species (ROS) metabolism. Here, one of the MPV17 homolog genes designated as PyM‐LP2 was selected for functional identification by introducing the encoding sequence region/reverse complementary fragment into the Py. yezoensis genome. Although the photosynthetic activity, the respiratory rate, and the ROS level in wild type (WT) and different gene‐transformed algal strains showed similar levels under normal conditions, the overexpression (OE) strain exhibited higher values of photosynthesis, respiration, and reducing equivalents pool size but lower intracellular ROS production under stress conditions compared with the WT. Conversely, all the above parameters showed opposite variation trends in RNAi strain as those in the OE strain. This implied that the PyM‐LP2 protein was involved in the mitigation of the oxidative stress. Sequence analysis revealed that this PyM‐LP2 protein was assorted to peroxisomes and might serve as a poring channel for transferring malate (Mal) to peroxisomes. By overexpressing PyM‐LP2, the transfer of Mal from chloroplasts to peroxisomes was enhanced under stress conditions, which promoted photorespiration and ultimately alleviated excessive reduction of the photosynthetic electron chain. This research lays the groundwork for the breeding of algae with enhanced resistance to oxidative stresses. [ABSTRACT FROM AUTHOR]

For problems such as low control accuracy, poor coordination and uneven pushing of hydraulic support in fully-mechanized coal mining face, an intelligent cooperative control method of hydraulic support is proposed based on driverless car technology . Each hydraulic support is regarded as a 'car' in fully mechanized mining face. The 'car' moves forward by moving support and adjusts driving direction by bottom adjustment and side guard plate adjustment. The group of hydraulic support is like a row of 'cars' moving forward in a certain order and maintaining alignment. Each hydraulic support has a fixed target travel, and is constrained by position of left and right side supports, so it can pay attention to operation of shearer in front and take into account status of the neighboring support, so as to realize intelligent cooperative control of hydraulic support. The method discusses intelligent cooperative control of hydraulic support from aspects of hydraulic support precise pushing control, parallel advancing control, protection plate control and closed-loop control of automatic following, which provides an idea for solving the control problems of hydraulic support in fully-mechanized coal mining face.

For low coal caving efficiency, poor coal caving quality and other problems existing in manual coal caving control mode of fully-mechanized top coal caving working face, an automatic memory coal caving control method was proposed by referring to memory coal cutting control idea of shearer. Automatic memory coal caving control obtains memory coal caving control data through exemplary learning. Electro-hydraulic control system of hydraulic support controls position and attitude of coal caving mechanisms of hydraulic support according to the memory coal caving control data, so as to realize coal caving quantity control through adjusting coal caving opening degree. Meanwhile, the coal caving quantity is calculated by a relationship model between position and attitude of the coal caving mechanisms and coal caving quantity, so as to correct the memory coal caving control data for avoiding overload of rear scraper conveyer. The method is applicable to top coal caving working faces which have stable coal seam with little thickness change.

Aiming at problem that fully mechanized caving face at the back end of fully mechanized top coal caving face adopted manual caving control method, its automation level differed greatly from that at the front end of fully mechanized top coal caving face, an automatic coal caving control system was studied. According to inclination sensors installed on top coal caving hydraulic support and travel sensors in jacks of front or rear scraper conveyor, position and attitude of caving mechanism of the hydraulic support are controlled to achieve precise control of caving quantity; by installing pan-tilt camera and infrared transmitter on tail beam of the hydraulic support, real-time video monitoring is carried out in whole process of coal caving to realize detection and control of coal transportation quantity and straightness of the rear scraper conveyor; image gray recognition technology is used to identify coal-gangue and detect gangue content of top coal. The system improves efficiency and quality of coal caving, and provides an idea for realizing unmanned fully mechanized top coal caving face.

In view of problem of low production efficiency of artificial drawing method on fully-mechanized coal face with sublevel caving, an automatic drawing control system was studied.Sonic sensors, vibrating sensors and ash sensors are installed on hydraulic supports. Through artificial demonstration operation and machine learning to memory sensor signals, sensor signal characteristic waveform during the end of drawing process is determined, and the similarity between collected vibration sensing signal, sound sensing signal and the characteristic signal is compared; the ash sensor is used to effectively identify inclusion rate of caved top coal. According to the similarity and inclusion rate, the system execute early warning or direct control to realize automatic drawing control which taking sensor-based sensing control as main control, time control as protection value, and remote intervention control as auxiliary control. The system improves automation level and production efficiency of fully-mechanized coal face with sublevel caving.

For software defect problem of electro hydraulic control system of hydraulic support, software structural features of the electro-hydraulic control system were analyzed from software testing method, software defect management framework was built, software testing schema was determined, and database structure of software defects database and software defect management flow were designed, so as to analyze software. The application shows that software quality and development efficiency of the electro-hydraulic control system are improved through software defect management.

The paper analyzed main methods of straightness control of fully-mechanized coal mining face and introduced working principle of straightness control. It used laser alignment sensor to design straightness control system in coal mining face, so as to achieve straightness control of hydraulic support. Underground principle experiment results show that the system can effectively control relative position of supports along the working face direction, and straightness control precision reaches 30 mm, which can meet requirements of straightness control of coal mining face.

In view of problem of low reliability of membrane switch type operation keyboard used in underground coal mine, the paper did demand analysis from aspects of using environment, operational requirements and ergonomics, and used the following methods to improve its reliability: used plastic dropping technology for the first time for keyboard-smashing performance protection to improve anti-smashing capacity of keyboard; through structural improvements to improve compaction of double faced adhesive tape of membrance, so as to improve capacities of sealing and humidity resistance of keyboard. Underground test results validate the mine-used membrane switch type operation keyboard with high reliability has good performance.

An automatic identification system of coal and gangue for fullly-mechanized coal caving working face based on vibration signal was proposed, structure and working principle of the system were introduced and design schemes of software and hardware of coal and gangue identification device were expounded as well as identification algorithm. The coal and gangue identification device identifies coal and gangue according to different vibration signals of coal and gangue falling on hydraulic support. Electro-hydraulic controller controls hydraulic support act according to identification result. The system has been tested with contents of identifiability of coal and gangue and controllability of automatic coal caving process in a mine and applied in some mines, which gets better effect.

Pyropia yezoensis can survive the severe water loss that occurs during low tide, making it an ideal species to investigate the acclimation mechanism of intertidal seaweed to special extreme environments. In this study, we determined the effects of high salinity on photosynthesis using increasing salinity around algal tissues. Both electron transport rates, ETR (I) and ETR (II), showed continuous decreases as the salinity increased. However, the difference between these factors remained relatively stable, similar to the control. Inhibitor experiments illustrated that there were at least three different cyclic electron transport pathways. Under conditions of severe salinity, NAD(P)H could be exploited as an endogenous electron donor to reduce the plastoquinone pool in Py. yezoensis. Based on these findings, we next examined how these different cyclic electron transport (CETs) pathways were coordinated by cloning the gene (HM370553) for ferredoxin-NADP+ oxidoreductase (FNR). A phylogenetic tree was constructed, and the evolutionary relationships among different FNRs were evaluated. The results indicated that the Py. yezoensis FNR showed a closer relationship with cyanobacterial FNR. The results of both real-time polymerase chain reaction and western blotting showed that the enzyme was upregulated under 90–120‰ salinity. Due to the structure-function correlations in organism, Py. yezoensis FNR was proposed to be involved in NAD(P)H-dependent Fd+ reduction under severe salinity conditions. Thus, through the connection between different donors bridged by FNR, electrons were channeled toward distinct routes according to the different metabolic demands. This was expected to make the electron transfer in the chloroplasts become more flexible and to contribute greatly to acclimation of Py. yezoensis to the extreme variable environments in the intertidal zone. [ABSTRACT FROM AUTHOR]