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  • A Probe into the Formation Process of “Bozhe” of the Han Official Script

    分类: 其他 >> 综合 提交时间: 2023-06-11 合作期刊: 《Art & Design Research》

    摘要: At the beginning of the 20th century, a large number of bamboo and silk manuscripts in the Han Dynasty were excavated, together with newly unearthed bronze and stone inscriptionsin which further deepened people's understanding of charactersin previous eras,To a certain extent, itfurtherverified the defined characteristics specific to strokes of Han official script based on epigraphy, such as, start like a silkworm head and end like a swallow tail, wavelike leftfalling stroke and rightfalling stroke as Zhe However, the beauty of the typical official script strokes came into being in steps, not all at once, Specifically, the formation process of Bozhe, as a symbol of mature strokes, was closely related to many influencing factors throughout its development process, such as the innovation of writing materials, the evolution of the characters themselves, etc. An in-depth analysis of this issue could not only help enrich the development path of wave formatio, but also deepen the understanding of formal beauty of Chinese characters.

  • A Psychophysiological Model of State Switching in Bipolar Disorder Based on the Salience Network

    分类: 心理学 >> 心理学其他学科 提交时间: 2024-05-06

    摘要: Bipolar disorder is a highly burdensome and refractory mental disorder, affecting individuals, families, and society. The challenge in bipolar disorderis that the treatment targeting the depressive state often carries the risk of inducing manic state, and vice versa, with the frequency of these alternating cycles often indicating the severity of the illness. Therefore, reducing the frequency of states switching in bipolar disorder patients and gradually achieving a stable state are crucial for effective treatment. The purpose of this study is to propose a dynamic process model of bipolar disorderstates switching in order to further understand the treatment, patterns of occurrence and development, and pathophysiological mechanisms of bipolar disorder. Considering the remarkable potential of the salience network in brain switching, we have anchored the model on the functionality of the salience network and analyzed and demonstrated the pathways involved in bipolar disorderstates switching within the framework of “physiological-psychological-neurological”. By focusing on the salience network, this model provides valuable insights into the mechanisms underlying bipolar disorderstates switching. 

  • Targeting pan-tumor antigens to activating Fcγ receptors generates a novel dendritic cell tumor vaccine

    分类: 医学、药学 >> 基础医学 提交时间: 2021-01-07

    摘要: Objective: Therapeutic tumor vaccines are eagerly awaited in clinic by patients with high expectations; however, very few clinically successful tumor vaccine has been developed thus far, and there remains no consensus on the generation of tumor vaccines. We hypothesized that targeted delivery of pan-tumor antigens instead of individual tumor-associated antigen (TAA) to dendritic cells via the activating receptor endocytic pathway (AREP) would provide an alternative avenue to develop potent personalized tumor vaccines. Methods: We first prepared biotin-tagged tumor antigens (B-TAgs) with mouse CT26. WT colorectal cancer cells by exploiting metabolic glycan labeling and bioorthogonal reaction methods; then, we prepared a bifunctional fusion protein containing streptavidin and a mouse IgG2a Fc fragment (SA-Fc), in which streptavidin was used for conjugation with B-TAgs, and Fc for mediating the interaction with the Fcγ receptor. Finally, conjugates (Fc-TAgs) of SA-Fc with B-TAgs were prepared based on affinity-guided noncovalent reaction. The phenotype of Fc-TAgs pulsed bone marrow-derived dendritic cells (BMDCs) was examined by flow cytometry. The therapeutic effects of Fc-TAgs pulsed BMDCs were observed in an established mouse CT26. WT colorectal cancer model. Results: The prepared B-TAgs covers almost all glycosylated tumor antigens. SA-Fc fusion protein exhibits biotin-binding activity as a homodimer. SA-Fc can effectively conjugate with B-TAg at a mixing ratio of 1:96 (w/w). Data of flow cytometry revealed that on Fc-TAgs pulsed BMDCs, the expression levels of surface molecules, such as CD80 and MHC II, were greatly increased. In the established murine colorectal cancer model, combination treatments with Fc-TAgs pulsed BMDCs and PD-1 blockade achieved significant therapeutic effects. Limitations: The strategy we proposed for the preparation of personalized tumor vaccine requires that the tumor be surgically removed from the patient. The rationality and validity of this strategy need to be proven by more preclinical investigations. Conclusions: The novel strategy we proposed circumvents the necessities for neoantigen prediction and provides an alternative pathway to establish a flexible system for the preparation of personalized dendritic cell tumor vaccines. In the setting of checkpoint blockade-based immunotherapy, a novel DCV would improve antitumor immunity and benefit the eradication of tumor residues within the body of the cancer patients.

  • Land cover change and eco-environmental quality response of different geomorphic units on the Chinese Loess Plateau

    分类: 生物学 >> 植物学 >> 应用植物学 提交时间: 2020-05-31 合作期刊: 《干旱区科学》

    摘要: Land cover in the Chinese Loess Plateau has undergone dramatic changes since the late 1980s. Revealing the trend in land cover change and eco-environmental quality response of different geomorphic units in this stage is a realistic requirement for promoting sustainable development of the Chinese Loess Plateau. Based on the data of geomorphic units and land cover in 1990, 2000, 2010 and 2018 of the Chinese Loess Plateau, we studied the trend of land cover change and eco-environmental quality response of different geomorphic units by using a significance index of land cover change, a proportion index of land cover change and an eco-environmental response model. The results indicated that from 1990 to 2018, the areas of forestland and construction land substantially increased, whereas those of cropland, grassland, wetland and unused land considerably decreased. Land cover change exhibited large geomorphic differences, and the main conversion of land cover was from cropland into other land types. Unstable trend of land cover change in the loess tablelands and sandy loess hills declined, whereas the unstable trends in the other geomorphic units enhanced. Eco-environmental quality varied among different geomorphic units. The expansion of construction land and degradation of forestland, grassland and wetland resulted in the deterioration of eco-environmental quality. The conversion of cropland and unused land into forestland and grassland, and the conversion of grassland into forestland were the main factors that drove the improvement of eco-environmental quality. The findings of this study may provide theoretical reference and support decision making for the optimization of land use structure and the improvement of eco-environmental quality on the Chinese Loess Plateau.

  • Land cover change and eco-environmental quality response of different geomorphic units on the Chinese Loess Plateau

    分类: 环境科学技术及资源科学技术 >> 环境科学技术基础学科 提交时间: 2020-04-23 合作期刊: 《干旱区科学》

    摘要: Land cover in the Chinese Loess Plateau has undergone dramatic changes since the late 1980s. Revealing the trend in land cover change and eco-environmental quality response of different geomorphic units in this stage is a realistic requirement for promoting sustainable development of the Chinese Loess Plateau. Based on the data of geomorphic units and land cover in 1990, 2000, 2010 and 2018 of the Chinese Loess Plateau, we studied the trend of land cover change and eco-environmental quality response of different geomorphic units by using a significance index of land cover change, a proportion index of land cover change and an eco-environmental response model. The results indicated that from 1990 to 2018, the areas of forestland and construction land substantially increased, whereas those of cropland, grassland, wetland and unused land considerably decreased. Land cover change exhibited large geomorphic differences, and the main conversion of land cover was from cropland into other land types. Unstable trend of land cover change in the loess tablelands and sandy loess hills declined, whereas the unstable trends in the other geomorphic units enhanced. Eco-environmental quality varied among different geomorphic units. The expansion of construction land and degradation of forestland, grassland and wetland resulted in the deterioration of eco-environmental quality. The conversion of cropland and unused land into forestland and grassland, and the conversion of grassland into forestland were the main factors that drove the improvement of eco-environmental quality. The findings of this study may provide theoretical reference and support decision making for the optimization of land use structure and the improvement of eco-environmental quality on the Chinese Loess Plateau.

  • New fossils of Late Pleistocene Sus scrofa from Yangjiawan Cave 2, Jiangxi, China

    分类: 生物学 >> 动物学 提交时间: 2020-09-15 合作期刊: 《古脊椎动物学报》

    摘要: The YJW (Yangjiawan) Cave 2 of Pingxiang in Jiangxi Province is a karst cave that developed in the Permian limestone of the Changxing Formation, which is filled with clay and grit of Late Pleistocene age. Six excavations have been conducted at the site since 2015. More than ten thousand mammalian fossils have been unearthed, and the wild boar fossils account for approximately 49%, which represents the richest wild boar fossil tooth collection of Pleistocene age in southern China. This study focuses on the studies of the canine teeth and the third molars, and mainly compares fossils of Sus peii and S. xiaozhu in South China and the data of extant S. scrofa respectively in dental morphology and odontometric data analyses which includes scatter plot analysis, regression analysis, coefficient of variation analysis and linear discriminant analysis. The typical scrofic type of the male’s lower canine teeth confirmed the identification of the suid fossils from YJW Cave 2 as S. scrofa. Although the male’s lower canines, the M2s and m3s, are among the most variable teeth in sizes, they stay in the ranges of S. scrofa; furthermore, the scatterplots of both the upper and lower third molars form two distinct clusters respectively, which can probably be attributed to sexual dimorphism rather than resulting from a mixture of different suid species. The post-Early Pleistocene suid fauna in southern China is almost only composed of S. scrofa, which is quite different from the adjacent Southeast Asia where the suid fauna is quite taxonomically diversified and dominated by the verrucosic type.

  • 多相单原子催化剂:一种新型的人工酶

    分类: 化学 >> 无机化学 提交时间: 2018-10-04

    摘要: 在这里,我们报告了一种高温气体迁移策略来制备多相的单原子铁催化剂,并展示其优良的类天然酶的活性(定义为单原子酶,SAE)。 结果表明,Fe SAE的局部定义明确的FeN4位点与含血红素的天然酶的活性金属中心高度相似。 Fe SAE表现出超级高的类过氧化物酶,氧化酶和过氧化氢酶的活性,超过了Fe3O4纳米酶40倍。更重要的是,Fe SAE可以有效活化过氧化氢(H2O2)产生羟基自由基(•OH)。 这使得其可以作为一种多相化的类Fenton系统,可以应对不断增加的环境污染。 我们的研究结果开辟了一个新的人造材料家族-模仿天然

  • New fossils of small and medium-sized bovids from the Early Pleistocene Site of Shanshenmiaozui in Nihewan Basin, North China

    分类: 生物学 >> 动物学 提交时间: 2022-04-16 合作期刊: 《古脊椎动物学报》

    摘要: Shanshenmiaozui site in Nihewan Basin in North China is a recently discovered Early Pleistocene site which yields rich and diverse mammalian fossils. In the fauna, the small and medium-sized bovid fossils are well represented and can be referred to the following taxa: Spirocerus wongi, Gazella sinensis, Ovis shantungensis and Megalovis piveteaui respectively, among which G. sinensis is the dominate species. S. wongi and G. sinensis are mainly represented by horn-cores and partial skull bones as well as mandibles; in addition, metacarpal and/or metatarsal bones were also recognized for all of the four species. The horn-cores are easy to be identified to the species level, while the dentitions and the postcranial bones underwent a series of examinations and comparisons before getting properly determined and referred to the most approximate taxa. Among the postcranial bones, the metapodials, especially to the metacarpal bones special attentions were paid, which are crucial not only for taxonomic identification, but also for phylogenetic and paleoecological reconstructions; the previously misidentified metapodial specimens in Nihewan fauna were reconsidered in this paper. In the SSMZ fauna, the bovid guild is dominated by Gazella and Bison, which indicates steppe was the most important biome in Nihewan Basin during Early Pleistocene.

  • Microbial adaptation to long-term N supply prevents large responses in N dynamics and N losses of a subtropical forest

    分类: 生物学 >> 生物化学 分类: 生物学 >> 生态学 提交时间: 2018-11-22

    摘要: Atmospherically-deposited nitrogen (N) can stimulate complex soil N metabolisms and accumulations over time. Whether long-term (decadal) N deposition effects on soil N transformations and functional microbes differ from the short-term (annual) effects have rarely been assessed. Here we conducted a laboratory 15N tracing study with soil samples from a short-term (one year) N addition site and a long-term (12 years) site in a subtropical forest. The effects of simulated N deposition on soil N2O emissions, N transformation rates and microbial nitrifying and denitrifying genes were determined. Our results showed that: (1) long-term N addition did not change soil N2O fluxes significantly in comparison to the short-term N addition. Denitrification, heterotrophic nitrification and autotrophic nitrification contributed 53%, 23% and 18% to total N2O emissions, respectively. (2) Autotrophic nitrification was the dominant N transformation process, except for the high-N treatment at the long-term site. The magnitude of soil N transformation rates was significantly different among N addition treatments but not between short- and long-term N addition sites. However, long-term N addition changed the responses of specific N transformation rates to N addition markedly, especially for the rates of nitrification, organic N mineralization to NH4+, NO3- immobilization and dissimilatory NO3- reduction to NH4+ (DNRA). (3) Responses of ammonia oxidizing archaea and bacteria (AOA and AOB) were stronger than denitrifying N2O-producers (nirK) and denitrifying N2O-reducers (nosZ) at the long-term site compared to the short-term site. (4) The close correlations among N2O flux, functional genes and soil properties observed at the short-term site was weakened at the long-term site, posing a decreased risk for N losses in the acid subtropical forest soils. There is evidence for an adaptation of functional microbial communities to the prevailing soil conditions and in response to long-term natural and anthropogenic N depositions.