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Salvia bowleyana is a traditional Chinese medicinal plant that is a source of nutritional supplements rich in salvianolic acid B and a potential experimental system for the exploration of salvianolic acid B biosynthesis in the Labiatae. Here, we report a high-quality chromosome-scale genome assembly of S. bowleyana covering 462.44 Mb, with a scaffold N50 value of 57.96 Mb and 44,044 annotated protein-coding genes. Evolutionary analysis revealed an estimated divergence time between S. bowleyana and its close relative S. miltiorrhiza of ~3.94 million years. We also observed evidence of a whole-genome duplication in the S. bowleyana genome. Transcriptome analysis showed that SbPAL1 (PHENYLALANINE AMMONIA-LYASE1) is highly expressed in roots relative to stem and leaves, paralleling the location of salvianolic acid B accumulation. The laccase gene family in S. bowleyana outnumbered their counterparts in both S. miltiorrhiza and Arabidopsis thaliana, suggesting that the gene family has undergone expansion in S. bowleyana. Several laccase genes were also highly expressed in roots, where their encoded proteins may catalyze the oxidative reaction from rosmarinic acid to salvianolic acid B. These findings provide an invaluable genomic resource for understanding salvianolic acid B biosynthesis and its regulation, and will be useful for exploring the evolution of the Labiatae.

Isochrysis galbana is considered an ideal bait for functional foods and nutraceuticals of humans because of its high fucoxanthin (Fx) content. However, multi-omics analysis of the regulation networks for Fx biosynthesis in I. galbana has not been reported. In this study, we report a high-quality genome sequence of I. galbana LG007, which has a 92.73 Mb genome size, with a contig N50 of 6.99 Mb and 14,900 protein-coding genes. Phylogenomic inferences confirmed the monophyly of Haptophyta, with I. galbana sister to Emiliania huxleyi and Chrysochromulina tobinii. Evolutionary analysis revealed an estimated divergence time between I. galbana and E. huxleyi of ∼ 133 million years ago (Mya). Gene family analysis indicated that lipid metabolism-related genes exhibited significant expansion, including IgPLMT, IgOAR1, and IgDEGS1. Metabolome analysis showed that the content of carotenoids in I. galbana cultured under green light for 7 days was higher than that of white light, and β-carotene was the main carotenoid, accounting for 79.09% of the total carotenoids. Comprehensive analysis of multi-omics analysis revealed that β-carotene, antheraxanthin, zeaxanthin, and Fx content was increased by green light induction, which was significantly correlated with the expression of IgMYB98, IgZDS, IgPDS, IgLHCX2, IgZEP, IgLCYb, and IgNSY. These findings contribute to understanding Fx biosynthesis and its regulation, providing a valuable reference for food and pharmaceutical applications.

Isochrysis galbana is an important producer in the aquatic ecosystem because of its rich fucoxanthin content and fast growth. However, little is known about its evolutionary adaptation to live in a specific, complex and harsh environment. We report a high-quality genome sequence of I. galbana LG007, which has a 92.73 Mb genome size, a contig N50 of 6.99 Mb and 14,900 protein-coding genes. Phylogenomic inferences confirmed the monophyly of Haptophyta, showing I. galbana is a sister to E. huxleyi and C. tobinii. Evolutionary analysis revealed an estimated divergence of I. galbana from its close relative E. huxleyi ~133 million years ago, and I. galbana underwent one round of whole-genome duplication. Genes related to environmental adaptation and metabolic regulation in I. galbana were relatively conserved, but the basic transcriptional regulation toolkit for terrestrial plant development has been contracted or was not detected. The domain identification of one novel fucoxanthin biosynthesis gene that encodes diadinoxanthin-fucoxanthin hydroxylase (DFH) was investigated. Comparative genomic analysis revealed that I. galbana acquired several transcription factors specific to the control of pigment accumulation and production of LHCX2 to harvest blue-green light, which facilitates adaptation to the underwater environment. These findings provide new insights into the genomic characteristics of I. galbana and algae evolution for adaptation to blue-green light underwater.

The Podostemaceae are ecologically and morphologically unusual aquatic angiosperms that survive only in rivers with pristine hydrology and high water quality and are at a relatively high risk of extinction. The taxonomic status of Podostemaceae has always been controversial. Here, we report the first high-quality genome assembly for Cladopus chinensis of Podostemaceae, obtained by incorporating Hi-C, Illumina and PacBio sequencing. We generated an 827.92 Mb genome with a contig N50 of 1.42 Mb and 27,370 annotated protein-coding genes. The assembled genome size was close to the estimated size, and 659.42 Mb of the assembly was assigned to 29 superscaffolds (scaffold N50 21.22 Mb). A total of 59.20% repetitive sequences were identified, among which long terminal repeats (LTRs) were the most abundant class (28.97% of the genome). Genome evolution analysis suggested that the divergence time of Cladopus chinensis (106 Mya) was earlier than that of Malpighiales (82 Mya) and that this taxon diverged into an independent branch of Podestemales. A recent whole-genome duplication (WGD) event occurred 4.43 million years ago. Comparative genomic analysis revealed that the expansion and contraction of oxidative phosphorylation, photosynthesis and isoflavonoid metabolism genes in Cladopus chinensis are probably related to the genomic characteristics of this growing submerged species. Transcriptome analysis revealed that upregulated genes in the shoot group compared to the root group were enriched in the NAC gene family and transcription factors associated with shoot development and defense responses, including WUSCHEL (WUS), ASYMMETRIC LEAVES (ASL), SHOOT MERISTEMLESS (STM), NAC2, NAC8, NAC29, NAC47, NAC73, NAC83 and NAC102. These findings provide new insights into the genomic diversity of unusual aquatic angiosperms and serve as a valuable reference for the taxonomic status and unusual shoot apical meristem of Podostemaceae.

The Podostemaceae are ecologically and morphologically unusual aquatic angiosperms that survive only in rivers with pristine hydrology and high water quality and are at a relatively high risk of extinction. The taxonomic status of Podostemaceae has always been controversial. Here, we report the first high-quality genome assembly for Cladopus chinensis of Podostemaceae, obtained by incorporating Hi-C, Illumina and PacBio sequencing. We generated an 827.92 Mb genome with a contig N50 of 1.42 Mb and 27,370 annotated protein-coding genes. The assembled genome size was close to the estimated size, and 659.42 Mb of the assembly was assigned to 29 superscaffolds (scaffold N50 21.22 Mb). A total of 59.20% repetitive sequences were identified, among which long terminal repeats (LTRs) were the most abundant class (28.97% of the genome). Genome evolution analysis suggested that the divergence time of Cladopus chinensis (106 Mya) was earlier than that of Malpighiales (82 Mya) and that this taxon diverged into an independent branch of Podestemales. A recent whole-genome duplication (WGD) event occurred 4.43 million years ago. Comparative genomic analysis revealed that the expansion and contraction of oxidative phosphorylation, photosynthesis and isoflavonoid metabolism genes in Cladopus chinensis are probably related to the genomic characteristics of this growing submerged species. Transcriptome analysis revealed that upregulated genes in the shoot group compared to the root group were enriched in the NAC gene family and transcription factors associated with shoot development and defense responses, including WUSCHEL (WUS), ASYMMETRIC LEAVES (ASL), SHOOT MERISTEMLESS (STM), NAC2, NAC8, NAC29, NAC47, NAC73, NAC83 and NAC102. These findings provide new insights into the genomic diversity of unusual aquatic angiosperms and serve as a valuable reference for the taxonomic status and unusual shoot apical meristem of Podostemaceae.

We demonstrate significantly longer plasmon lifetime and stronger electric field enhancement by lifting the nanoantenna arrays above the substrate by dielectric nanopillars. The role of the pillar is to offer a more homogeneous dielectric background allowing stronger diffraction coupling among plasmonic nanoantennas leading to a Fanolike asymmetric lineshape. It is found that the electric fields around the nanoantennas can be greatly enhanced when the Fanolike resonance is excited, and a 4.2 times enhancement is achieved compared with the pure resonance in individual nanoantennas. Furthermore, only a collective surface mode with its electric fields of the same direction as the induced electric moment in the nanoantennas could mediate the excitation of such a Fanolike resonance. More importantly, the sensitivity and the figure of merit (FOM) of this plasmonic structure can reach as high as 900 nm/RIU and 53, respectively. Our study offers a new, simple, and efficient way to design the plasmonic systems with desired electric field enhancement and spectral lineshape for different applications.

The basic structure and work mechanism of laser-triggered vacuum switch (LTVS) are introduced briefly in this paper, and the processes of primary plasma production and expansion are analyzed as well. A series of experiments has been carried out with different gap voltages, laser wavelengths, laser energies, polarity configuration modes, switch structures, focal lengths, and laser waveforms. The switch structure is modified to improve the heavy-current capability of the switch, and the gap distance is increased to improve the voltage capacity. The special design of the trigger structure can reduce the dependence on the laser energy of the switch and the time delay. A new laser waveform of LTVS multiple wave crests could further decrease the laser energy, and it is the research basis of laser trigger miniaturization and its application in the LTVS.

We present a powerful method to enhance the magnetic plasmon (MP) resonances of metamaterials composed of periodic arrays of U-shaped metallic split-ring resonators (SRRs) for high-quality sensing. We show that by suspending the metamaterials to reduce the effect of the substrate, the strong diffraction coupling of MP resonances can be achieved, which leads to a narrow-band mixed MP mode with a large magnetic field enhancement. It is also shown that for such a diffraction coupling, the magnetic field component of the lattice resonance mode of periodic arrays must be parallel to the induced magnetic moment in the metallic SRRs. Importantly, the sensitivity and the figure of merit (FOM) of the suspended metamaterials can reach as high as 1300 nm/RIU and 40, respectively. These results suggest that the proposed metamaterials may find great potential applications in label-free biomedical sensing.

The semantic function of the ? bei passive sentence has been characterized in various ways. It has been claimed by some scholars that its primary function is to indicate that the referent of the subject, the speaker or the hearer is adversely affected by the action, event or state represented in the sentence. It has also been claimed that the construction can sometimes be used neutrally, without any adversity implications. It has further been claimed that it can sometimes be used with positive implications. But little attempt has been made in the past to show exactly when the construction acquires which of these three implications (i.e., adversative, neutral, and positive). This paper attempts to answer that question. It proposes that the semantic/discourse function of the bei-passive sentence is to indicate that the referent of the subject, the speaker (or the person whose point of view (s)he is representing) or the hearer receives a major impact which is above a certain threshold from the action, event, or state represented in the sentence. The impact can be either direct, as is the case with high-impact verbs (e.g., ? da ‘hit’, ?? kaichu ‘fire’), indirect (as is the case with low or no impact verbs such as ?? kanjian ‘see’, ? hen ‘hate’), or both. It shows that a generalization that is based on ‘EITHER a major direct impact OR a major indirect impact’ does not work. It proposes that the semantic/discourse function of the bei-passive sentence is to indicate that the SUM of the direct and indirect impacts that the referent of the subject, the speaker (or the person whose point of view (s)he is representing) or the hearer receives is at or above the threshold for a major impact.

This paper reports an empirical study that examined the widespread practice of using songs in language teaching for young learners. The study may represent the first methodologically rigorous assessment of vocabulary acquisition through songs as used in language teaching. Over a seven-week period including fifteen 40-minute classes, three groups of students from two private kindergartens in Beijing were taught five short English phrases of 4-8 words through each of three conditions (songs, choral repetition, control) in a within-subject repeated measures design. Vocabulary acquisition was measured by the number of meaningful morphemes produced by the students in a picture description task administered before and after the teaching period. Results indicated significant acquisition for items learned through songs and choral repetition, but not for control items. The implication is that songs may indeed contain ünportant pedagogical value.

In this paper, a multi-electrode laser-triggered vacuum switch (LTVS) is developed to optimize the triggered vacuum switch (TVS) and meet the requirements of the pulsed power technology. The relationship between the laser trigger energy, operating voltage, polarity, average energy of the spot and the trigger characteristics which mainly contain the delay time, jitter time and minimum operating voltage is analyzed in detail. The interaction between a thermal mechanism and an ion collision mechanism is proposed to explain the switch conduction. It is concluded that the minimum delay time and the jitter time can reach 15 ns and ± 10 ns, respectively. The minimum operating voltage of 60 V is observed. Finally, the delay time is mainly decided by the average energy of the spot in the case of certain triggering energy and the polarity effect is one of the main factors affecting trigger stability.

In this paper, a modified laser-trigged vacuum switch(LTVS) is developed to optimize the triggered vacuum switch (TVS) and complies with the requirements of pulsed power technology. The comparison between a flat-electrode type switch and a multi-electrode type switch is discussed founded on the simulation and experimental results. The results show that the delay time of the modified switch can reach as low as 17 ns and the operating voltage ranges from 60V to 20KV. Finally, laser energy influencing the trigger characteristics is analyzed built on the thermionic mechanism.

A laser-triggered vacuum switch (LTVS) is an advanced closing switch with nanosecond delay and jitter. In order to enhance hold-off voltage and extend the service lifetime of an LTVS, we designed a multichannel laser-triggered vacuum switch (MLTVS) utilizing a cone-shaped target electrode placed on the cathode platform. The fabrication and testing of the MLTVS is described in this paper. Experimental results show that the working voltage of the MLTVS with a gap distance of 12 mm is from 30 V to 20 kV. The threshold energy for triggering the switch is 0.4 mJ corresponding to a peak power density of 27.9 MW/cm(2). The triggering lifetime of a spot can reach up to 18,000 shots. In addition, the relationship between triggering lifetime and target materials is analyzed using a field emission scanning electron microscope. A hypothesis of the vacuum gap's triggering mechanism is discussed based on the measured results.

The CO2SINK project is the first on-shore pilot CO2 storage study in Europe and Address a number of the Key Aspects related to geological storage of CO2 . Different Seismic Surveys Have Been Carried Out in the project , Such as time-lapse Seismic and surface moving source profiling ( MSP , Also known as walk -away VSP ) Surveys . We Have investigated the feasibility of coda -wave Interferometry Analysis for Monitoring of CO2 Injection Using time-lapse VSP synthetic data based on a project site CO2SINK elastic model . Our studies Suggest That coda -wave Interferometry Analysis Could Potentially Be A Reliable and Effective tool for monitoring Geological Carbon Sequestration .

Seismic amplitude information and data from an injection well (IW) and an observation well (OW2) are used to estimate reflection coefficients. Seismic volumes are extracted near the two boreholes from a baseline and a monitor survey. An anhydrite layer above the reservoir generates a high amplitude reflection and this is used for calibration. The amplitude equation of Ghaderi and Landro (2009) is used to estimate R0 for the reservoir. In the IW it is between 0.1-0.12 and in OW2 it is between 0.1-0.14 for the baseline survey. These values correspond well to logging data, providing confidence in our approach. We use the same method on the monitor survey and find R0 in the IW is now in the range 0.26-0.31 and R0 in OW2 is now 0.13-0.16, indicating lower CO2 saturation in OW2.