“詩言志”之本義謭論 : 讀朱自清先生《詩言志辨》札記

朱自清先生《詩言志辨》，認為“詩言志”之基本内涵是言説思想意志用以教化，强調其思想旨趣在於政教。這個學術影響巨大的認知，其實是對漢代詩學思想的整理和提煉,與“詩言志”之本義不完全相符。本文從先秦“詩言志”之實踐和闡説、詩人自道“詩言志”之内涵以及“詩言志”訓詁三個方面，重新梳理“詩言志”之本義，以為其不僅包含“表達思想意志”之義，也包含“抒發情感”和“紀事論理”之義。 In Shiyanzhibian, Zhu Ziqing believes that the essence of shiyanzhi is that the purpose of expressing thoughts and ideas is to emphasize the significance of official propaganda. This conviction, which has major academic influence, is actually an induction of the overall poetic thoughts of Han Dynasty, rather than aiming at the essence of shiyanzhi. This essay holds this argument from three aspects: the practice and interpretation of shiyanzhi of pre-Qin period, the illustrations of shiyanzhi of poets themselves, and exegetical studies (xungu) of shiyanzhi. In doing so, this essay reevaluates the very essence of shiyanzhi, and proposes that shiyanzhi contains not only the meaning of illustrating ideological thoughts, but also includes expressing emotions and the ethics of narratives

Power Loss and Thermal Analysis of a MW High-Speed Permanent Magnet Synchronous Machine

High speed permanent magnet synchronous machines (PMSMs) have attracted much attention due to their high power density, high efficiency, and compact size for direct-drive applications. However, the consequent power loss density is high and heat transfer is also deemed as a technical challenge. This is particularly the case for high-speed operation. In this paper, electromagnetic and mechanical power losses in a MW level high speed PMSM is comprehensively investigated by finite element analysis; the transient machine demagnetization performance is studied with the proposed rotor composite structure to improve the machine anti-demagnetization capability; the temperature distribution of the high speed PMSM is also analyzed by a fluid-thermal coupling method with calculated power loss. The high speed PMSM is prototyped and experimentally tested to validate the effectiveness of numerical models and calculated results

RHINO: Regularizing the Hash-based Implicit Neural Representation

The use of Implicit Neural Representation (INR) through a hash-table has demonstrated impressive effectiveness and efficiency in characterizing intricate signals. However, current state-of-the-art methods exhibit insufficient regularization, often yielding unreliable and noisy results during interpolations. We find that this issue stems from broken gradient flow between input coordinates and indexed hash-keys, where the chain rule attempts to model discrete hash-keys, rather than the continuous coordinates. To tackle this concern, we introduce RHINO, in which a continuous analytical function is incorporated to facilitate regularization by connecting the input coordinate and the network additionally without modifying the architecture of current hash-based INRs. This connection ensures a seamless backpropagation of gradients from the network's output back to the input coordinates, thereby enhancing regularization. Our experimental results not only showcase the broadened regularization capability across different hash-based INRs like DINER and Instant NGP, but also across a variety of tasks such as image fitting, representation of signed distance functions, and optimization of 5D static / 6D dynamic neural radiance fields. Notably, RHINO outperforms current state-of-the-art techniques in both quality and speed, affirming its superiority.Comment: 17 pages, 11 figure

Differential microRNA expression between shoots and rhizomes in Oryza longistaminata using high-throughput RNA sequencing

AbstractPlant microRNAs (miRNAs) play important roles in biological processes such as development and stress responses. Although the diverse functions of miRNAs in model organisms have been well studied, their function in wild rice is poorly understood. In this study, high-throughput small RNA sequencing was performed to characterize tissue-specific transcriptomes in Oryza longistaminata. A total of 603 miRNAs, 380 known rice miRNAs, 72 conserved plant miRNAs, and 151 predicted novel miRNAs were identified as being expressed in aerial shoots and rhizomes. Additionally, 99 and 79 miRNAs were expressed exclusively or differentially, respectively, in the two tissues, and 144 potential targets were predicted for the differentially expressed miRNAs in the rhizomes. Functional annotation of these targets suggested that transcription factors, including squamosa promoter binding proteins and auxin response factors, function in rhizome growth and development. The expression levels of several miRNAs and target genes in the rhizomes were quantified by RT-PCR, and the results indicated the existence of complex regulatory mechanisms between the miRNAs and their targets. Eight target cleavage sites were verified by RNA ligase-mediated rapid 5′ end amplification. These results provide valuable information on the composition, expression and function of miRNAs in O. longistaminata, and will aid in understanding the molecular mechanisms of rhizome development

Identification of rhizome-specific genes by genome-wide differential expression Analysis in Oryza longistaminata

<p>Abstract</p> <p>Background</p> <p>Rhizomatousness is a key component of perenniality of many grasses that contribute to competitiveness and invasiveness of many noxious grass weeds, but can potentially be used to develop perennial cereal crops for sustainable farmers in hilly areas of tropical Asia. <it>Oryza longistaminata</it>, a perennial wild rice with strong rhizomes, has been used as the model species for genetic and molecular dissection of rhizome development and in breeding efforts to transfer rhizome-related traits into annual rice species. In this study, an effort was taken to get insights into the genes and molecular mechanisms underlying the rhizomatous trait in <it>O. longistaminata </it>by comparative analysis of the genome-wide tissue-specific gene expression patterns of five different tissues of <it>O. longistaminata </it>using the Affymetrix GeneChip Rice Genome Array.</p> <p>Results</p> <p>A total of 2,566 tissue-specific genes were identified in five different tissues of <it>O. longistaminata</it>, including 58 and 61 unique genes that were specifically expressed in the rhizome tips (RT) and internodes (RI), respectively. In addition, 162 genes were up-regulated and 261 genes were down-regulated in RT compared to the shoot tips. Six distinct <it>cis</it>-regulatory elements (CGACG, GCCGCC, GAGAC, AACGG, CATGCA, and TAAAG) were found to be significantly more abundant in the promoter regions of genes differentially expressed in RT than in the promoter regions of genes uniformly expressed in all other tissues. Many of the RT and/or RI specifically or differentially expressed genes were located in the QTL regions associated with rhizome expression, rhizome abundance and rhizome growth-related traits in <it>O. longistaminata </it>and thus are good candidate genes for these QTLs.</p> <p>Conclusion</p> <p>The initiation and development of the rhizomatous trait in <it>O. longistaminata </it>are controlled by very complex gene networks involving several plant hormones and regulatory genes, different members of gene families showing tissue specificity and their regulated pathways. Auxin/IAA appears to act as a negative regulator in rhizome development, while GA acts as the activator in rhizome development. Co-localization of the genes specifically expressed in rhizome tips and rhizome internodes with the QTLs for rhizome traits identified a large set of candidate genes for rhizome initiation and development in rice for further confirmation.</p

Manipulating rhizosphere microorganisms to improve crop yield in saline-alkali soil: a study on soybean growth and development

IntroductionRhizosphere microorganisms can effectively promote the stress resistance of plants, and some beneficial rhizosphere microorganisms can significantly promote the growth of crops under salt stress, which has the potential to develop special microbial fertilizers for increasing the yield of saline-alkali land and provides a low-cost and environmentally friendly new strategy for improving the crop yield of saline-alkali cultivated land by using agricultural microbial technology.MethodsIn May 2022, a field study in a completely randomized block design was conducted at the Heilongjiang Academy of Agricultural Sciences to explore the correlation between plant rhizosphere microorganisms and soybean growth in saline-alkali soil. Two soybean cultivars (Hening 531, a salt-tolerant variety, and 20_1846, a salt-sensitive variety) were planted at two experimental sites [Daqing (normal condition) and Harbin (saline-alkali conditions)], aiming to investigate the performance of soybean in saline-alkali environments.ResultsSoybeans grown in saline-alkali soil showed substantial reductions in key traits: plant height (25%), pod number (26.6%), seed yield (33%), and 100 seed weight (13%). This underscores the unsuitability of this soil type for soybean cultivation. Additionally, microbial analysis revealed 43 depleted and 56 enriched operational taxonomic units (OTUs) in the saline-alkali soil compared to normal soil. Furthermore, an analysis of ion-associated microbes identified 85 mOTUs with significant correlations with various ions. A co-occurrence network analysis revealed strong relationships between specific mOTUs and ions, such as Proteobacteria with multiple ions. In addition, the study investigated the differences in rhizosphere species between salt-tolerant and salt-sensitive soybean varieties under saline-alkali soil conditions. Redundancy analysis (RDA) indicated that mOTUs in saline-alkali soil were associated with pH and ions, while mOTUs in normal soil were correlated with Ca2+ and K+. Comparative analyses identified significant differences in mOTUs between salt-tolerant and salt-sensitive varieties under both saline-alkali and normal soil conditions. Planctomycetes, Proteobacteria, and Actinobacteria were dominant in the bacterial community of saline-alkali soil, with significant enrichment compared to normal soil. The study explored the functioning of the soybean rhizosphere key microbiome by comparing metagenomic data to four databases related to the carbon, nitrogen, phosphorus, and sulfur cycles. A total of 141 KOs (KEGG orthologues) were identified, with 66 KOs related to the carbon cycle, 16 KOs related to the nitrogen cycle, 48 KOs associated with the phosphorus cycle, and 11 KOs linked to the sulfur cycle. Significant correlations were found between specific mOTUs, functional genes, and phenotypic traits, including per mu yield (PMY), grain weight, and effective pod number per plant.ConclusionOverall, this study provides comprehensive insights into the structure, function, and salt-related species of soil microorganisms in saline-alkali soil and their associations with salt tolerance and soybean phenotype. The identification of key microbial species and functional categories offers valuable information for understanding the mechanisms underlying plant-microbe interactions in challenging soil conditions