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Summary: A novel hybrid‐multiplexed fifteen‐switch converter (HM‐15SC) topology, which can simultaneously output a set of three‐phase AC and three sets of DC, is proposed to address the problems of a single type of power electronic converter and the complexity of coordinated control of AC/DC hybrid systems for smart grid. In this paper, we conduct a detailed analysis of the topology and operating principles of HM‐15SC. This includes an examination of the converter's effective switching states in relation to output voltage, current paths, and maximum voltage stress. In addition, a modulation strategy combining single‐leg independent model prediction current control (SL‐MPCC) and time‐sharing cooperative (TSC) ideas is proposed to establish a single‐leg AC current prediction model, which effectively reduces the prediction arithmetic under the premise of realizing three‐leg independent prediction control and optimal control of AC/DC hybrid outputs. Finally, we verify the feasibility and superiority of the proposed HM‐15SC topology and its modulation strategy using the Typhoon HIL 402 platform. [ABSTRACT FROM AUTHOR]

Summary: Tubulin folding cofactors (TFCs) are required for tubulin folding, α/β tubulin heterodimer formation, and microtubule (MT) dynamics in yeast and mammals. However, the functions of their plant counterparts remain to be characterized.We identified a natural maize crumpled kernel mutant, crk2, which exhibits reductions in endosperm cell number and size, as well as embryo/seedling lethality. Map‐based cloning and functional complementation confirmed that ZmTFCB is causal for the mutation.ZmTFCB is targeted mainly to the cytosol. It facilitates α‐tubulin folding and heterodimer formation through sequential interactions with the cytosolic chaperonin‐containing TCP‐1 ε subunit ZmCCT5 and ZmTFCE, thus affecting the organization of both the spindle and phragmoplast MT array and the cortical MT polymerization and array formation, which consequently mediated cell division and cell growth. We detected a physical association between ZmTFCB and the maize MT plus‐end binding protein END‐BINDING1 (ZmEB1), indicating that ZmTFCB1 may modulate MT dynamics by sequestering ZmEB1.Our data demonstrate that ZmTFCB is required for cell division and cell growth through modulating MT homeostasis, an evolutionarily conserved machinery with some species‐specific divergence. See also the Commentary on this article by Fan, 239: 1537–1538. [ABSTRACT FROM AUTHOR]

Machining feature recognition is a key technology to realize CAD/CAPP/CAM system integration. Aiming at high robustness of traditional processing feature recognition in image reasoning, an automatic processing shape recognition method based on fuzzy learning of processing surrounding point black data is proposed. The Cloud RNN in the PointNet stage strongly demonstrates that the framework originates from convolutional neural spider webs. Protector shape for detailed discoloration data on constructed prominence surfaces for automatic rifle recognition is conducted. Spot staining data sample library is also constructed. The prosecuting feature recognizer gained advantages through sample training, which realized robot-style notification of 36 processing shapes. This is conducted with a recognition accuracy rate of over 90%. The method is simple and efficient, although it is not suitable for point cloud data with backlash and defects. It is sensible and still has usable robustness and confirmation performance against mischief around shape peripheries due to shape intersections. [ABSTRACT FROM AUTHOR]

The machine-driven products processed by CNC machine tools are divided into multiple parts, which are often transmitted to unqualified processing crystals due to the error of the part's posture, thus affecting the projection effect. Aiming at handling this problem, we, in this work, propose a method for locating and correcting machine capabilities based on bicycle visual recognition. The robot obtains coordinates and offset points through the vision system. In order to satisfy the requirement of fast sorting of the robot parts, a robot species method (BAS-GA) that supports machine vision and improved genetic algorithm rules is proposed. The rank method first preprocesses the part copies, then uses the Sift feature twin similarity notification algorithm to filter the part idols, and finally uses in-law deformation to place the target parts. Afterward, an particular model is built for the maintenance of the nurtural skill, and the mathematical mold is solved using the BAS-GA algorithmic program authority. The close trail of the robot is maintained to manifest the marijuana of the robot. Experimental inference have shown that the BAS-GA algorithm rule achieves the optimal conclusion similar to the pseudo-annealing algorithmic program plant. Meanwhile, the genetic algorithm rule is modified ant settlement algorithm program. Knife sharpening was also reduced by 7%, inferring that this process can effectively improve the robot's action success rate. [ABSTRACT FROM AUTHOR]

Because cotton is the most important fiber crop, the differentiation and development mechanism of cotton fiber cells has been a hot topic in cotton research. NAC (for NAM, ATAF, and CUC2) is a class of plant‐specific transcription factor families that regulate multiple aspects of plant growth and development. Previously, we identified 33 differentially expressed NAC genes in upland cotton based on fiber‐related transcriptome profiling. In this study, we conducted chromosome localization, systematic evolution, and gene structural analysis of 242 NAC genes genome‐wide based on a high‐quality reference genome of upland cotton. In addition, the expression pattern analysis of 16 differentially expressed GhNACs was carried out by RT–PCR using ovules at early fiber initiation stages of n2 recessive naked seed mutant (n2NSM) and Xuzhou142 fuzzless–lintless mutant (Xu142fl). The results showed that GhNAC230 and GhNAC115 were most closely related to AtSND1 and downregulated in ovules of Xu142fl compared with n2NSM. Quantitative RT–PCR (qRT–PCR) analysis of GhNAC230 demonstrated its gradual accumulation from −1 days postanthesis (DPA) to 1 DPA in n2NSM and further confirmed its downregulated expression in 1 DPA ovules of Xu142fl compared to n2NSM. The current study predicted a pair of NAC genes that might be key candidate genes that are crucial for lint fiber development. [ABSTRACT FROM AUTHOR]

Summary: Riboflavin is the precursor of essential cofactors for diverse metabolic processes. Unlike animals, plants can de novo produce riboflavin through an ancestrally conserved pathway, like bacteria and fungi. However, the mechanism by which riboflavin regulates seed development is poorly understood. Here, we report a novel maize (Zea mays L.) opaque mutant o18, which displays an increase in lysine accumulation, but impaired endosperm filling and embryo development. O18 encodes a rate‐limiting bifunctional enzyme ZmRIBA1, targeted to plastid where to initiate riboflavin biosynthesis. Loss of function of O18 specifically disrupts respiratory complexes I and II, but also decreases SDH1 flavinylation, and in turn shifts the mitochondrial tricarboxylic acid (TCA) cycle to glycolysis. The deprivation of cellular energy leads to cell‐cycle arrest at G1 and S phases in both mitosis and endoreduplication during endosperm development. The unexpected up‐regulation of cell‐cycle genes in o18 correlates with the increase of H3K4me3 levels, revealing a possible H3K4me‐mediated epigenetic back‐up mechanism for cell‐cycle progression under unfavourable circumstances. Overexpression of O18 increases riboflavin production and confers osmotic tolerance. Altogether, our results substantiate a key role of riboflavin in coordinating cellular energy and cell cycle to modulate maize endosperm development. [ABSTRACT FROM AUTHOR]

Both chimeric (anti-PD-L1-8A1 and anti-TIGIT-31C3) and humanized (anti-PD-L1-#77, anti-TIGIT-T26 and T87) antibodies showed binding and blocking capabilities comparable to corresponding positive controls (Figure 1A-D), i.e., atezolizumab (Tencentriq) for anti-PD-L1 and tiragolumab for anti-TIGIT. Anti-PD-L1 antibody potently inhibited the tumour growth of MC38-hPD-L1 (Figure 1G; Figure S3) and anti-TIGIT inhibited MC38 cells (Figure 1H). PD-L1/TIGIT bispecific antibody showed survival advantage in animal model To obtain a well-behaved anti-PD-L1/TIGIT molecule, eight BsAb antibodies (Bs#1-Bs#8) containing anti-TIGIT-huT26 or huT87 in IgG4, and anti-PD-L1-hu#77 in scFv were generated (Figure S5A). [Extracted from the article]

Interestingly, BsAb in IgG4 could couple PD1-expressing CHO cells (CHO-PD1) to HER2-expressing NCI-N87 cells, significantly increasing the percentage of double-staining cell population (Figure 2H,I). (H) HER2/PD1 BsAb could couple HER2-expressing NCI-N87 and PD1- expressing CHO-PD1 cells. PD1/HER2 bound to PD1 protein with affinity comparable to pembrolizumab, while HER2/PD1 exhibited moderately reduced affinity (Figure S1C). *p < .05, **p < .01, ***p < .001 by two-way ANOVA gl HER2/PD1 BsAb in IgG1 subclass may launch ADCC and CDC attacks on HER2-expressing tumour cells as well as PD1-expressing activated T cells. [Extracted from the article]

A three‐dimensional (3D) microscopic finite element (FE) cutting model was developed with the thermo‐mechanical coupling for carbon fiber reinforced polymer (CFRP) composites in this article. The model predictions of cutting force, machined surface, and cutting temperature at various fiber orientations were obtained and compared with the experimental data. It was shown that the 3D microscopic cutting model can predict the cutting force, cutting temperature, and subsurface damage precisely. The behavior of cutting force has presented an obviously cyclical variation characteristics at the fiber orientations of 0°, 45°, and 90°, and different chip morphologies were obtained correspondingly. The temperature fields of machined surface were studied at the four different fiber orientations, in which the maximum residual temperature on the machined surface occurs at 90°. The heat‐induced resin coating and resin ridges on the machined surface were obviously observed at the fiber orientations of 45° and 135°. The trend curve of cutting temperature is more similar with that of thrust force by comparing with cutting force, which meaning, unlike the isotropic metal materials, the thrust force has the direct effect on the heat generation. In addition, the comparison of depth of thermal and mechanical subsurface damage was also performed, it was showed that the depths of thermal subsurface damage are close to that of mechanical subsurface damage in the range of 0°–45°, and the thermal subsurface damage decrease while the mechanical subsurface damage increases with the increase of the fiber orientation range from 90° to 180°. [ABSTRACT FROM AUTHOR]

In field crop systems, biocontrol efficiency supported by various predators is not always enhanced with occurring simultaneously but can be reduced by predator interference, i.e., competition between predator individuals over access to their prey. Such interference may be related to the active time of each predator. In this study, predator exclusion experiments were used to selectively exclude either one or both predators and to examine the impact of the two predator groups on the suppression of cotton aphid (Aphis gossypii Glover) populations in a cotton field. Main predator species included Propylaea japonica (Thunberg) and Harmonia axyridis Pallas in the ladybird group, and Lycosa spp. and Erigone spp in the spider group. A greater number of spiders was observed in the morning and evening, while ladybird densities did not vary during the day. Removing all predators led to an increase in aphid numbers compared to the other treatments where predators were present. Removing either spiders or ladybirds had similar impacts on aphid control. It is likely that spiders provide an equal level of aphid mortality as ladybirds. When both spiders and ladybirds were present, aphid abundance did not differ from those treatments where only one predator group was present. The presence of both predators did not lead to more aphid suppression, indicating that interference between these predators may have occurred in the cotton field. Although these two predators partly diverged in their activity rhythms, interference may still have occurred and could be common in cotton fields. [ABSTRACT FROM AUTHOR]

Three‐phase AC–DC converter based on integrated transformer is a novel converter which is capable of handling high power levels and can realise power factor correction function. Owing to different parameter tolerances of the primary windings, grid current could be unbalanced, which usually could not be solved through traditional control methods. To handle this problem, a current balancing method is adopted in this study to improve former current control loop. Meanwhile, based on the principle of instantaneous power balance, a dual loop control strategy with an outer voltage loop and an inner current loop is designed. Besides, load current feedforward control is introduced to enhance the dynamic response. Moreover, phase‐shift control is employed as the modulation method, in which duty ratios change along with sinusoidal signals. Simulation and experimental results show that the control strategy could make the three‐phase current of the converter sinusoidal and balanced. [ABSTRACT FROM AUTHOR]

Numerous tremors occur during excavation and mining periods in coal mines, and low-energy tremors often occur before strong tremors. In addition, it is found that not all strong tremors cause rockbursts. Therefore, generating behaviors of strong tremors and the triggering criterion for the occurrence of the rockburst must be investigated. In this study, generating behaviors of strong tremors were inferred by velocity tomograms and energy density clouds. An innovative facility capable of applying dynamic disturbance to roadway models was developed to study the triggering criterion for rockbursts. Velocity tomograms indicated that the stress concentration extended to the syncline region with the advance of the coalface. High-energy-density clouds expanded rapidly and regularly in some areas that were parts of the high-velocity region, indicating that the stress increased rapidly in these areas, until strong tremors took place nearby. AE activities suggested that the modelled roadway offered good resistance as the dynamic loading energy grew from 29.4 J to 117.6 J. Then, sharp AE activity at the dynamic loading energy of 147 J indicated the ultimate shock resistance of the roadway was almost reached. Finally, bursting failure of the modelled roadway was observed at a dynamic loading energy of 176.4 J. [ABSTRACT FROM AUTHOR]

At present, coal bursts in working faces of steeply inclined coal seams (SICSs) have rarely been investigated, and current research focuses on the influences of roof breaking and instability of overlying structures in goaf on coal bursts; however, the stress state of coal masses in working faces being subjected to coal bursts is rarely researched. To overcome the above defects, a model for analysing stresses on coal masses in horizontal section of SICSs was established based on the coal burst that occurred in LW5521-20, Yaojie No. 3 Coal Mine, Lanzhou, Gansu Province, China. Moreover, the mechanism underpinning such a coal burst in SICSs was analysed based on the superposition mechanism of dynamic and static loads. The results show that the side abutment pressure near the roof and floor under the horizontal sections of SICSs is asymmetrically distributed in the vertical direction in which the peak of side abutment pressure near the roof is closer to the working face and therefore is taken as the source of static loads for coal bursts in working faces. When the superimposed dynamic load caused by hanging roof breaking and high static load borne in the coal masses is larger than the critical load for coal burst inception, a coal burst will occur. Furthermore, the superimposed dynamic load induced by coal bursts on the support and the initial static load on the supports are larger than their limiting load, which leads to support collapse and eventually causes dynamic failure of the working face. The coal burst in working faces in horizontal sections of SICSs can be prevented by using deep-hole presplit blasting in a hard roof, destress blasting in coal masses, and support optimisation of working faces, showing a favourable preventative effect. [ABSTRACT FROM AUTHOR]

Mitochondria are semi-autonomous organelles that are the powerhouse of the cells. Plant mitochondrial RNA editing guided by pentatricopeptide repeat ( PPR) proteins is essential for energy production., We identify a maize defective kernel mutant dek36, which produces small and collapsed kernels, leading to embryos and/or seedlings lethality. Seed filling in dek36 is drastically impaired, in line with the defects observed in the organization of endosperm transfer tissue. Positional cloning reveals that DEK36, encoding a mitochondria-targeted E+ subgroup PPR protein, is required for mitochondrial RNA editing at atp4-59, nad7-383 and ccm F N -302, thus resulting in decreased activities of mitochondrial complex I, complex III and complex IV in dek36., Loss-of-function of its Arabidopsis ortholog At DEK36 causes arrested embryo and endosperm development, leading to embryo lethality. At_dek36 also has RNA editing defects in atp4, nad7, ccm F N 1 and ccm F N 2, but at the nonconserved sites. Importantly, efficiency of all editing sites in ccm F N 1, ccm F N 2 and rps12 is severely decreased in At_dek36, probably caused by the impairment of their RNA stabilization., These results suggest that the DEK36 orthologue pair are essential for embryo and endosperm development in both maize and Arabidopsis, but through divergent function in regulating RNA metabolism of their mitochondrial targets. [ABSTRACT FROM AUTHOR]

Benzene sulphonamide intermediates and two series of branched azo dyes (one series with H-Acid as the coupling component, and the other, with a pyrazolone derivative as the coupling component) derived from them were synthesised. The molecular structures, spectroscopic properties and dyeing properties of the dyes obtained have been investigated. The results indicated that these dyes showed one dominant hue, despite each separate branch of chromophore, and, in the first series, four chromophoric groups led to only a threefold increase in the extinction coefficient, while the same comparison in the second series produced a fully additive effect, i.e. a fourfold increase. Compared with the mono-branch dye of each series, the dyeing properties of the H-Acid series were improved, whereas the pyrazolone series that were run diversely for the two series were synthesised from different coupling components. In addition, the crystallographic structure of the tri-branch intermediate showed a non-coplanar structure, which indicated that the derived dye would perform as the sum of three similar chromophoric units. [ABSTRACT FROM AUTHOR]

Introduction Cereals are an important source of food, feed and fuel with a rapidly increasing global demand. However, cereal seeds contain high levels of starch and polysaccharides, making the isolation of high quality RNA extremely difficult. Objective To develop a novel method for extracting high quality total RNA from various starch- and polysaccharides-rich cereal seeds, such as maize, rice, sorghum and wheat. Methodology We developed a modified sodium dodecyl sulphate (SDS)/TRIzol method. The combined use of a Tris buffer (pH 9.0) and SDS before TRIzol extraction effectively resolved the problem of seed homogenate solidification in such a buffer. A high concentration of SDS was used separately, not only to promote cell lysis but also to effectively dissolve seed sample containing high levels of starch. Moreover, acid phenol saturated with 0.1 m citrate buffer (pH 4.3) was used to separate RNA from DNAs, proteins and high levels of starch. This rapid protocol was compared with other RNA isolation methods preferentially used for plants rich in polysaccharides and secondary metabolites. Results Gel electrophoresis analysis indicated that the extracted total RNA had good integrity without apparent DNA contamination. Furthermore, an A260/280 ratio of approximately 2.0, an A260/230 ratio of more than 2.0 and RIN values of more than 8.6 indicated that the isolated RNA was of high purity. The isolated RNA was suitable for subsequent molecular manipulations, such as reverse-transcription polymerase chain reaction (PCR), rapid amplification of cDNA ends (RACE) and real-time PCR. Conclusion The study has described an easy, efficient and highly reproducible method for RNA isolation from various cereal seeds. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Expansins are unique plant cell wall proteins that possess the ability to induce immediately cell wall extension in vitro and cell expansion in vivo. To investigate the biological functions of expansins that are abundant in wood-forming tissues, we cloned two expansin genes from the differentiating xylem of Chinese fir ( Cunninghamia lanceolata (Lamb.) Hook). Phylogenetic reconstruction indicated that they belong to α-expansin (EXPA), named ClEXPA1 and ClEXPA2. Expression pattern analysis demonstrated that they are preferentially expressed in the cambium region. Overexpression of ClEXPA1 and ClEXPA2 in tobacco plants yielded pleiotropic phenotypes of plant height, stem diameter, leaf number and seed pod. The height and diameter growth of the 35S: ClEXPA1 and 35S: ClEXPA2 transgenic plants were increased drastically, exhibiting an enlargement of pith parenchyma cell size. Isolated cell walls of ClEXPA1 and ClEXPA2 overexpressors contained 30%-50% higher cellulose contents than the wild type, accompanied by a thickening of the cell walls in the xylem region. Both ClEXPA1 and ClEXPA2 are involved in plant growth and development, with a partially functional overlap. Expansins are not only able to induce cell expansion in different tissues/organs in vivo, but they also can act as a potential activator during secondary wall formation by directly or indirectly affecting cellulose metabolism, probably in a cell type-dependent manner. [ABSTRACT FROM AUTHOR]