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BACKGROUND: The present study aimed to assess the efficacy of a new haplo-paraspinal-muscle-preserving (HMP) laminoplasty technique in the treatment of cervical myelopathy. METHODS: The medical records of 68 patients diagnosed with multisegmental cervical myelopathy were retrospectively reviewed. Of these, 22 patients who underwent HMP laminoplasty were defined as the muscle-preserved group (MP), and 46 patients who underwent traditional open-door laminoplasty were enrolled and defined as the traditional open-door laminoplasty group (LP). Patient demographic data and surgical parameters like clinical and radiological parameters, operation duration, blood loss, and spinal canal expansion distance were compared. RESULTS: Average surgical time and blood loss were significantly reduced in the MP group when compared with the LP group (P < 0.05). Both groups demonstrated significant improvements in neurological function and spinal canal expansion (P > 0.05). However, the visual analog scale score in the MP group was significantly lower compared with the LP group at the 6-month follow-up (P < 0.05), but no differences were found at the 1-year follow-up. The loss of lordosis was more prominent in the LP group when compared with the MP group at 1-year follow-up (P < 0.05). Lower events of persistent axial pain were found in the MP group but with no statistical significance. More hinge side laminae fractures could be found in the MP group, but more hinge side displacements were found in the LP group. CONCLUSIONS: The HMP laminoplasty technique is relatively safe, effective, easier to perform, and better for lordosis maintenance and complication control compared with the traditional open-door technique. CLINICAL RELEVANCE: Although traditional open-door laminoplasty is an efficient approach in treating multisegmental cervical myelopathy, the complications could significantly affect the clinical outcome. Our new HMP laminoplasty technique has a lower complication rate and a better lordosis maintenance ability; therefore, it could be a better choice in treating multisegmental cervical myelopathy. LEVEL OF EVIDENCE: 3.

In this paper, a small hydropower microgrid solution with high applicability is proposed to solve the problem of high line failure rate and long maintenance time, which can improve the reliability of distribution network in mountainous areas. In this scheme, small hydropower and local load constitute a low-cost but efficient microgrid operation to improve the reliability of rural electricity. In this scheme, small-sized hydropower and local load constitute microgrid operation. In case of failure, the scheme makes full use of the independent operation of microgrid to provide qualified power quality to local load. This scheme is easy to realize and does not need additional energy storage, so it has good economy. Firstly, the frequency disturbance characteristics of small hydropower microgrid is analyzed, which lays a theoretical foundation for small hydropower microgrid operation. Then it introduces the island operation mode to grid-connected operation mode transition of small hydropower, including the key technologies such as frequency adjustment strategy in island operation stage. Finally, the simulation studies show the effectiveness of the method.

This article mainly studies the characteristics of transformer inrush current and the influence of different factors on transformer inrush current. This article states the background and significance of the inrush current, introduces the research status of the inrush current and the suppression technology. The suppression of the inrush current is the root of the problem. The mechanism of the inrush current is derived mathematically from the magnetic flux relationship, and the characteristics of the inrush current are analyzed through its related waveform diagrams. On this basis, the harm of inrush current is introduced. The core method is based on the PSCAD simulation platform to build the inrush current and the circuit to suppress the inrush current, and to set the parameters for simulation model. This article discusses the effects of transformer capacity, closing angle, knee voltage and basic parameters on inrush current.

High-density cultivation using dwarfing rootstocks is widely practiced worldwide. The root is an essential organ for apple rootstocks, especially for dwarfing rootstocks. However, few studies about the root traits of apple rootstocks have been published. In this study, the root growth characteristics of the 'Red Fuji' apple cultivar scions grafted onto Shao series no. 40 (RF/SH.40) and Baleng Crab (RF/BC) rootstocks, which have apparent size-controlling differences, were investigated. Subsequently, the tree morphological and leaf photosynthetic parameters were measured, and the correlation between the roots and branches was studied. Thus, the root system of RF/BC was more widely distributed than that of RF/SH.40, with higher volume, projected area, surface area, root number, and length of the root system. Multiple comparisons revealed that the number of roots might be the critical factor contributing to differences in the two root systems. Furthermore, RF/BC had higher leaf photosynthetic rates, water use efficiency, and branch numbers and length than RF/SH.40. RF/BC had a wider branch distribution in a vertical orientation; however, a wider branch distribution in a horizontal orientation and a higher rate of branches shorter than 15 cm was observed for RF/SH.40. The above-ground tree architecture and below-ground root traits tend to be positively correlated. The parameters that primarily affected the correlation between above- and below-ground were branch volume, branch number, total projected, and total surface area of the root system.

‘Red Fuji’ apple (Malus × domestica Borkh.) scions were grafted onto eight size-controlling rootstock combinations (dwarfing, semi-dwarfing, and vigorous types). During the third year after grafting, morphological and physiological parameters, such as growth, hydraulic conductance, non-structural carbohydrates, gas exchange and chlorophyll fluorescence, as well as leaf anatomy, were examined and instantaneous whole-canopy photosynthetic assimilation was modelled. Compared with Baleng, rootstocks M.9 and B.9 resulted in reduced growth vigour and photosynthetic capacity. Significantly lower soil-to-leaf hydraulic conductance, stomatal density and palisade/spongy parenchyma ratios were also observed in ‘Red Fuji’ grafted on M.9 and B.9. We propose that the down-regulated hydraulic conductance contributed to the decline in photosynthetic rate, which in turn caused a reduction in instantaneous whole-canopy photosynthetic assimilation. These results provide evidence that the limited photosynthetic capacity and leaf area are major causes of the reduced canopy photosynthetic assimilation observed in M.9 and B.9 grafted apple trees. The reduced photosynthetic assimilation may partly result from a sustained lower photochemical efficiency. However, dwarfing and semi-dwarfing rootstocks grafted plants contained more starch, which may be a significant factor underlying the observed advanced precocity.

With the development of intelligent substation, substations rely more on network communication to transmit substation information. High substation automations with reliable communication avoid the traditional complicated operation which needs to be done manually, and improve the efficiency of substation operation. But higher requirements for the reliability of information integrity are put forward. The protection setting of intelligent substation directly affects the correctness of the protection devices (Intelligent Electronic Device) and further affects the normal operation of the entire power system. Because the protection setting of protective devices is affected by power system operation mode, season climate and many other factors, the protection setting often needs to be adjusted. When the number of protection devices in substation is increasing rapidly, the frequent change of the protection setting can easily cause the missing or omission of protection setting for certain protection devices, resulting in the potential danger of the power system. On view of the above problems, combined with the development trend of IEC61850, this paper focuses on the on-line management of protection devices. By studying the data attribute of the online management of protection device settings and combining the layered network structure of the intelligent substation, the online management system for protection device settings is constructed, with the aim to eliminate the hidden danger caused by the missing or omission of protection setting.

For power grids with abundant small hydropower in China, the efficient switching process between small hydropower and distribution network will help to reduce the user outage time and the cutting of hydropower and load. This paper mainly adopts the simulation method combined with the regulation characteristics of small hydropower in rural areas. And the paper focuses on the amplitude and frequency characteristics of the initial stage of small hydropower. Firstly, the operation characteristics of small hydropower plants are studied, and the simulation model is built. Next, we study the amplitude frequency characteristics of small hydropower stations with better control capability such as leading phase operation. Further, in view of the large number of small hydropower stations with no phase operation capability in the rural power grid, we studied the simulation in the initial stage of the isolated network. By comparing and analyzing the operation characteristics of small hydropower stations at different initial stages under different conditions, it can provide support for small hydropower stations to reconnect into distribution network as soon as possible. This will help to reduce the tedious and long process of grid connection in the rural power grid.

Cucumber is one of the most important vegetables that are very sensitive to low-light stress. The specific mechanism involved is poorly understood. Here we investigate the expression profile of genes induced by low-light stress in Cucumis sativus seedlings with suppression subtractive hybridization (SSH). cDNA prepared from cucumber seedlings treated with 100 μmol m −2 s −1 light intensity as testers and cDNA from unstressed cucumber seedlings with 800 μmol m −2 s −1 light intensity as drivers. A forward subtractive cDNA library was constructed, from which 768 recombinant colonies were picked and amplified. Through differential screening of the subtractive cDNA library, 246 clones were identified as low-light stress induced. After sequencing, 64 unique expressed sequence tags (ESTs) were obtained by clustering and blast analysis, which included some functionally unknown transcripts. Of the 64 ESTs, 50 ESTs identity to their homolog in GenBank, 14 ESTs were expected to be novel genes. The ESTs with significant protein homology were sorted into 16 groups according to the functional categories of the Arabidopsis proteins.

In this paper, we studied the periodic solution, connecting orbits between singular points and global structure in Oregonator.