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Genetic Types of Meter-Scale Cyclic Sequences and Fabric Natures of Facies Succession 被引量:14
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作者 Mei Mingxiang Xu Debin Zhou Hongrui Institute of Earth Sciences and Natural Resources, China University of Geosciences, Beijing 100083 《Journal of Earth Science》 SCIE CAS CSCD 2000年第4期3-10,共8页
Different genetic types of meter-scale cyclic sequences in stratigraphic records result from episodic accumulation of strata related to Milankovitch cycles. The distinctive fabric natures of facies succession result f... Different genetic types of meter-scale cyclic sequences in stratigraphic records result from episodic accumulation of strata related to Milankovitch cycles. The distinctive fabric natures of facies succession result from the sedimentation governed by different sediment sources and sedimentary dynamic conditions in different paleogeographical backgrounds, corresponding to high-frequency sea-level changes. Naturally, this is the fundamental criterion for the classification of genetic types of meter-scale cyclic sequences. The widespread development in stratigraphic records and the regular vertical stacking patterns in long-term sequences, the evolution characters of earth history and the genetic types reflected by specific fabric natures of facies successions in different paleogeographical settings, all that show meter-scale cyclic sequences are not only the elementary working units in stratigraphy and sedimentology, but also the replenishment and extension of parasequence of sequence stratigraphy. Two genetic kinds of facies succession for meter-scale cyclic sequence in neritic-facies strata of carbonate and clastic rocks, are normal grading succession mainly formed by tidal sedimentation and inverse grading succession chiefly made by wave sedimentation, and both of them constitute generally shallowing upward succession, the thickness of which ranges from several tens of centimeters to several meters. The classification of genetic types of meter-scale cyclic sequence could be made in terms of the fabric natures of facies succession, and carbonate meter-scale cyclic sequences could be divided into four types: L-M type, deep-water asymmetrical type, subtidal type and peritidal type. Clastic meter-scale cyclic sequences could be grouped into two types: tidal-dynamic type and wave-dynamic type. The boundaries of meter-scale cyclic sequences are marked by instantaneous punctuated surface formed by non-deposition resulting from high-frequency level changes, which include instantaneous exposed punctuated surface, drowned punctuated surface as well as their relative surface. The development of instantaneous punctuated surface used as the boundary of meter-scale cyclic sequence brings about the limitations of Walter's Law on the explanation of facies distribution in time and space, and reaffirm the importance of Sander's Rule on analysis of stratigraphic records. These non-continuous surface could be traced for long distance and some could be correlative within same basin range. The study of meter-scale cyclic sequences and their regularly vertical stacking patterns in long-term sequences indicate that the research into cyclicity of stratigraphic records is a useful way to get more regularity from stratigraphic records that are frequently complex as well as non-integrated. 展开更多
关键词 genetic types fabric natures of facies succession meter-scale cyclic sequences.
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ON THE DIFFERENCES OF THE NATURES OF AUPOINTS AND CHINESE HERBAL MEDICINES
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作者 李艳芬 庄礼兴 《World Journal of Acupuncture-Moxibustion》 2007年第1期41-45,共5页
The acupoints and Chinese herbal medicines are quite different in their natures. In the present paper, the authors expound the differences of the natures between the acupoints and Chinese herbal medicines from a) sub... The acupoints and Chinese herbal medicines are quite different in their natures. In the present paper, the authors expound the differences of the natures between the acupoints and Chinese herbal medicines from a) substance carriers, b) the underlying mechanism in actions, and c) individual characteristics, etc.. 展开更多
关键词 The nature of acupoints The nature of Chinese herbs Efficacy Differences
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On the Natures of English Passive Construction Based on Theta Theory
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作者 王丽 《海外英语》 2016年第22期186-187,共2页
The study of English passive construction has always been one of the hot topics in the literature of Generative Grammar. Although many attempts have been made, the study of this structure is still not systematic enoug... The study of English passive construction has always been one of the hot topics in the literature of Generative Grammar. Although many attempts have been made, the study of this structure is still not systematic enough especially in terms of its essential natures. The present study is designed to give a full explanation of natures of English passive construction from the perspective of theta theory, which can provide English learners with a deeper understanding of passive structure. 展开更多
关键词 passive structure theta theory natures
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Genomic and phenotypic signatures provide insights into the wide adaptation of a global plant invader 被引量:1
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作者 Yan Hao Xin-Feng Wang +8 位作者 Yaolin Guo Tian-Yang Li Ji Yang Malika LAinouche Armel Salmon Rui-Ting Ju Ji-Hua Wu Lin-Feng Li Bo Li 《Plant Communications》 SCIE CSCD 2024年第4期275-290,共16页
Invasive alien species are primary drivers of biodiversity loss and species extinction.Smooth cordgrass(Spartina alterniflora)is one of the most aggressive invasive plants in coastal ecosystems around the world.Howeve... Invasive alien species are primary drivers of biodiversity loss and species extinction.Smooth cordgrass(Spartina alterniflora)is one of the most aggressive invasive plants in coastal ecosystems around the world.However,the genomic bases and evolutionary mechanisms underlying its invasion success have remained largely unknown.Here,we assembled a chromosome-level reference genome and performed phenotypic and population genomic analyses between native US and introduced Chinese populations.Our phenotypic comparisons showed that introduced Chinese populations have evolved competitive traits,such as earlyflowering time and greater plant biomass,during secondary introductions along China’s coast.Population genomic and transcriptomic inferences revealed distinct evolutionary trajectories of low-and high-latitude Chinese populations.In particular,genetic mixture among different source populations,together with in-dependent natural selection acting on distinct target genes,may have resulted in high genome dynamics of the introduced Chinese populations.Our study provides novel phenotypic and genomic evidence showing how smooth cordgrass rapidly adapts to variable environmental conditions in its introduced ranges.Moreover,candidate genes related toflowering time,fast growth,and stress tolerance(i.e.,salinity and submergence)provide valuable genetic resources for future improvement of cereal crops. 展开更多
关键词 ADAPTATION natural selection invasive species population genomics Spartina alterniflora
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Impacts of Nutlin-3a and exercise on murine double minute 2-enriched glioma treatment
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作者 Yisheng Chen Zhongcheng Fan +11 位作者 Zhiwen Luo Xueran Kang Renwen Wan Fangqi Li Weiwei Lin Zhihua Han Beijie Qi Jinrong Lin Yaying Sun Jiebin Huang Yuzhen Xu Shiyi Chen 《Neural Regeneration Research》 SCIE CAS 2025年第4期1135-1152,共18页
Recent research has demonstrated the impact of physical activity on the prognosis of glioma patients,with evidence suggesting exercise may reduce mortality risks and aid neural regeneration.The role of the small ubiqu... Recent research has demonstrated the impact of physical activity on the prognosis of glioma patients,with evidence suggesting exercise may reduce mortality risks and aid neural regeneration.The role of the small ubiquitin-like modifier(SUMO)protein,especially post-exercise,in cancer progression,is gaining attention,as are the potential anti-cancer effects of SUMOylation.We used machine learning to create the exercise and SUMO-related gene signature(ESLRS).This signature shows how physical activity might help improve the outlook for low-grade glioma and other cancers.We demonstrated the prognostic and immunotherapeutic significance of ESLRS markers,specifically highlighting how murine double minute 2(MDM2),a component of the ESLRS,can be targeted by nutlin-3.This underscores the intricate relationship between natural compounds such as nutlin-3 and immune regulation.Using comprehensive CRISPR screening,we validated the effects of specific ESLRS genes on low-grade glioma progression.We also revealed insights into the effectiveness of Nutlin-3a as a potent MDM2 inhibitor through molecular docking and dynamic simulation.Nutlin-3a inhibited glioma cell proliferation and activated the p53 pathway.Its efficacy decreased with MDM2 overexpression,and this was reversed by Nutlin-3a or exercise.Experiments using a low-grade glioma mouse model highlighted the effect of physical activity on oxidative stress and molecular pathway regulation.Notably,both physical exercise and Nutlin-3a administration improved physical function in mice bearing tumors derived from MDM2-overexpressing cells.These results suggest the potential for Nutlin-3a,an MDM2 inhibitor,with physical exercise as a therapeutic approach for glioma management.Our research also supports the use of natural products for therapy and sheds light on the interaction of exercise,natural products,and immune regulation in cancer treatment. 展开更多
关键词 exercise and SUMO-related gene signatures(ESLRS) glioblastoma management low-grade glioma natural bioactives neural regeneration physical exercise
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Potential role and therapeutic implications of glutathione peroxidase 4 in the treatment of Alzheimer's disease
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作者 Yanxin Shen Guimei Zhang +4 位作者 Chunxiao Wei Panpan Zhao Yongchun Wang Mingxi Li Li Sun 《Neural Regeneration Research》 SCIE CAS 2025年第3期613-631,共19页
Alzheimer's disease is an age-related neurodegenerative disorder with a complex and incompletely understood pathogenesis. Despite extensive research, a cure for Alzheimer's disease has not yet been found. Oxid... Alzheimer's disease is an age-related neurodegenerative disorder with a complex and incompletely understood pathogenesis. Despite extensive research, a cure for Alzheimer's disease has not yet been found. Oxidative stress mediates excessive oxidative responses, and its involvement in Alzheimer's disease pathogenesis as a primary or secondary pathological event is widely accepted. As a member of the selenium-containing antioxidant enzyme family, glutathione peroxidase 4 reduces esterified phospholipid hydroperoxides to maintain cellular redox homeostasis. With the discovery of ferroptosis, the central role of glutathione peroxidase 4 in anti-lipid peroxidation in several diseases, including Alzheimer's disease, has received widespread attention. Increasing evidence suggests that glutathione peroxidase 4 expression is inhibited in the Alzheimer's disease brain, resulting in oxidative stress, inflammation, ferroptosis, and apoptosis, which are closely associated with pathological damage in Alzheimer's disease. Several therapeutic approaches, such as small molecule drugs, natural plant products, and non-pharmacological treatments, ameliorate pathological damage and cognitive function in Alzheimer's disease by promoting glutathione peroxidase 4 expression and enhancing glutathione peroxidase 4 activity. Therefore, glutathione peroxidase 4 upregulation may be a promising strategy for the treatment of Alzheimer's disease. This review provides an overview of the gene structure, biological functions, and regulatory mechanisms of glutathione peroxidase 4, a discussion on the important role of glutathione peroxidase 4 in pathological events closely related to Alzheimer's disease, and a summary of the advances in small-molecule drugs, natural plant products, and non-pharmacological therapies targeting glutathione peroxidase 4 for the treatment of Alzheimer's disease. Most prior studies on this subject used animal models, and relevant clinical studies are lacking. Future clinical trials are required to validate the therapeutic effects of strategies targeting glutathione peroxidase 4 in the treatment of Alzheimer's disease. 展开更多
关键词 apoptosis ferroptosis inflammation lipid peroxidation natural plant products neurodegenerative disorder NEUROPROTECTION oxidative stress small-molecule drugs
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Heterogeneity of mature oligodendrocytes in the central nervous system
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作者 Chao Weng Adam M.R.Groh +4 位作者 Moein Yaqubi Qiao-Ling Cui Jo Anne Stratton G.R.Wayne Moore Jack P.Antel 《Neural Regeneration Research》 SCIE CAS 2025年第5期1336-1349,共14页
Mature oligodendrocytes form myelin sheaths that are crucial for the insulation of axons and efficient signal transmission in the central nervous system.Recent evidence has challenged the classical view of the functio... Mature oligodendrocytes form myelin sheaths that are crucial for the insulation of axons and efficient signal transmission in the central nervous system.Recent evidence has challenged the classical view of the functionally static mature oligodendrocyte and revealed a gamut of dynamic functions such as the ability to modulate neuronal circuitry and provide metabolic support to axons.Despite the recognition of potential heterogeneity in mature oligodendrocyte function,a comprehensive summary of mature oligodendrocyte diversity is lacking.We delve into early 20th-century studies by Robertson and Río-Hortega that laid the foundation for the modern identification of regional and morphological heterogeneity in mature oligodendrocytes.Indeed,recent morphologic and functional studies call into question the long-assumed homogeneity of mature oligodendrocyte function through the identification of distinct subtypes with varying myelination preferences.Furthermore,modern molecular investigations,employing techniques such as single cell/nucleus RNA sequencing,consistently unveil at least six mature oligodendrocyte subpopulations in the human central nervous system that are highly transcriptomically diverse and vary with central nervous system region.Age and disease related mature oligodendrocyte variation denotes the impact of pathological conditions such as multiple sclerosis,Alzheimer's disease,and psychiatric disorders.Nevertheless,caution is warranted when subclassifying mature oligodendrocytes because of the simplification needed to make conclusions about cell identity from temporally confined investigations.Future studies leveraging advanced techniques like spatial transcriptomics and single-cell proteomics promise a more nuanced understanding of mature oligodendrocyte heterogeneity.Such research avenues that precisely evaluate mature oligodendrocyte heterogeneity with care to understand the mitigating influence of species,sex,central nervous system region,age,and disease,hold promise for the development of therapeutic interventions targeting varied central nervous system pathology. 展开更多
关键词 aging central nervous system diseases electron microscopy HETEROGENEITY immunohistochemistry myelin sheath natural history NEUROGLIA OLIGODENDROGLIA single-cell gene expression analysis
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Harnessing artificial intelligence for identifying conflicts of interest in research
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作者 Abdulqadir J Nashwan 《World Journal of Methodology》 2025年第1期6-8,共3页
This editorial explores the transformative potential of artificial intelligence(AI)in identifying conflicts of interest(COIs)within academic and scientific research.By harnessing advanced data analysis,pattern recogni... This editorial explores the transformative potential of artificial intelligence(AI)in identifying conflicts of interest(COIs)within academic and scientific research.By harnessing advanced data analysis,pattern recognition,and natural language processing techniques,AI offers innovative solutions for enhancing transparency and integrity in research.This editorial discusses how AI can automatically detect COIs,integrate data from various sources,and streamline reporting processes,thereby maintaining the credibility of scientific findings. 展开更多
关键词 Artificial intelligence Conflicts of interest TRANSPARENCY Research integrity Natural language processing
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Droog纽约首展Secret natures
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作者 Ron Lam Galerie Kreo 《明日风尚》 2009年第6期110-110,共1页
荷兰品牌Droog今年二月在纽约开设分店,店里除了售卖自家出品的家具外,还设有展览场地,以举办不定期的产品或艺术展览,首个展览于五月中开始举行。这场名叫Secret Natures的展览共展出四件来自不同设计师的作品,当中包括西班牙设计师Nac... 荷兰品牌Droog今年二月在纽约开设分店,店里除了售卖自家出品的家具外,还设有展览场地,以举办不定期的产品或艺术展览,首个展览于五月中开始举行。这场名叫Secret Natures的展览共展出四件来自不同设计师的作品,当中包括西班牙设计师Nacho Carbonell的家具系列Skin。Skin被由弹力物料制成的外衣包裹着, 展开更多
关键词 Droog SECRET natures SKIN MIRROR 二字 中粉
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健康宠物生命——Natures Gift“贵族”——鸸鹋油高密度营养猫粮
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作者 数次 《宠物派》 2006年第9期100-101,共2页
如果你的猫咪总是对饭碗里的猫粮毫无兴趣,连耸耸鼻子发表个评价都不愿意;如果你的猫咪如前面健康文章中的一样,被毛生涩、暗晦,或正在遭遇皮肤问题;如果你的猫咪因为某些猫粮中廉价的添加剂正在引发健康危机……很多东西,失去后才懂得... 如果你的猫咪总是对饭碗里的猫粮毫无兴趣,连耸耸鼻子发表个评价都不愿意;如果你的猫咪如前面健康文章中的一样,被毛生涩、暗晦,或正在遭遇皮肤问题;如果你的猫咪因为某些猫粮中廉价的添加剂正在引发健康危机……很多东西,失去后才懂得珍惜。如果上述情况正在发生,作为主人恐怕难辞其咎,其实选择一种配方健康、营养,质地、味道一流的猫粮,足以让猫咪受益终生—— 展开更多
关键词 natures GIFT 营养成分 天然食物 蛋白质来源 猫癣 水果蔬菜 枣实 新毛 流浪猫 真菌感
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Expression of the difference between the Cold(Han) and Hot(Re) natures of traditional Chinese medicines(Strobal and Rhubarb) based on the cold/hot plate differentiating assay 被引量:10
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作者 ZHAO HaiPing1,2, ZHAO YanLing1, WANG JiaBo1, LI HanBing1,2, REN YongShen1,2, ZHOU CanPing1,3, YAN Dan1 & XIAO XiaoHe1· 1 China Military Institute of Chinese Materia Medica, 302 Military Hospital, Beijing 100039, China 2 Chengdu University of Traditional Chinese Medicine, Chengdu 610075, China 3 Hunan University of Chinese Medicine, Changsha 410208, China 《Science China(Life Sciences)》 SCIE CAS 2009年第12期1192-1197,共6页
In this study, objective differences between the Cold (Han) and Hot (Re) nature of traditional Chinese medicines, e.g. Strobal and Rhubarb, are determined by using a cold/hot plate differentiation technology. A novel,... In this study, objective differences between the Cold (Han) and Hot (Re) nature of traditional Chinese medicines, e.g. Strobal and Rhubarb, are determined by using a cold/hot plate differentiation technology. A novel, self-designed cold/hot plate differentiating instrument, with methodological study, was used to investigate the intervention of Strobal and Rhubarb on the temperature tropism of mice. Compared with the ICR and BALB/c mice, it was found that KM mice on the cold/hot plate were more sensitive to the change of temperature, within the tolerant temperature range of 15-40 ℃ . The temperature tropism behavior of mice is influenced by treatment with Rhubarb and Strobal, as is the activity of ATPase in liver tissue. These trends are consistent with the definition of the Cold/Hot nature of Chinese medicines based on traditional Chinese medicinal theory. This study showed that the differences of the Cold/Hot nature of traditional Chinese medicines. might be objectively represented by the temperature tropism of animal by means of cold/hot differentiating assay. 展开更多
关键词 RHUBARB Strobal Cold/Hot nature of Chinese MEDICINES cold/hot plate DIFFERENTIATING ASSAY
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Towards a scientific rationale for traditional properties of Chinese medicinal plants: “natures” and “flavors” 被引量:2
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作者 Li-ping Li Ben-gang Zhang +17 位作者 Zhao Zhang Xiao-jin Li Guo-ping Wang Hai-long Song Cong-zhao Fan Yang-ming Jiang Tuo Wang Hui-hui Zhao Wei-hong Cui Jiang-shan Lai Xiu-lian Chi Xue-ping Wei Chong-ming Wu Yao-dong Qi Hai-tao Liu Pei-gen Xiao Eimear Nic Lughadha Christine J.Leon 《Chinese Herbal Medicines》 CAS 2019年第3期258-266,共9页
Objective: According to theory of Chinese medicine property, the ecological environment shapes properties(natures and flavors) of Chinese materia medica(CMM) and there are close relationships between certain natures a... Objective: According to theory of Chinese medicine property, the ecological environment shapes properties(natures and flavors) of Chinese materia medica(CMM) and there are close relationships between certain natures and flavors. However, to date these observations have not been validated scientifically in the context of the whole flora of a region. The present study aims to address this gap.Methods: We collected geographical distributions of 3637 vascular plant species native to the Xinjiang region of northwest China, of which around 812 are medicinal plants. The CMM property characters of these medicinal plants were also collected. All medicinal plants were then analyzed in the occurrence of their natures(cold, cool, neutral, warm, and hot) and flavors(sweet, bitter, sour, salty, and pungent). Possible correlations between these properties and environmental factors, notably climate, as well as correlations with plant species richness of the wider native flora of Xinjiang were then investigated using permutation test and regression.Results: Cold species(38.5%) were more numerous than warm(21.0%) and neutral(22.3%), while bitter species(43.3%) were more numerous than pungent(25.6%), sweet(22.4%) and sour(6.7%) ones. Species with bitter flavor were most commonly also cold(48.6%) in nature, sour flavor usually coincided with cold(44.2%) or cool nature(26.0%), whereas pungent or sweet species tended to be warm(34.4%, 28.4%) or neutral(27.8%, 28.4%). The percentages of species of cold/cool nature, bitter flavor were higher in mountainous regions, and the percentages of warm/neutral and pungent/sweet/sour were higher in basins. The percentages of species of cold/cool, bitter were positively correlated with actual evapotranspiration(AET),and also plant species richness but had a bell-shaped relationship with potential evapotranspiration(PET),whereas the inverse situation was shown for warm/neutral and pungent/sweet/sour species.Conclusion: Analysis of the data in Xinjiang region of China supports the qualitative observations concerning natures and flavors in traditional theory of Chinese medicine property. Specifically,(i) certain natures and flavors co-occur more frequently than if randomly distributed;(ii) correlations between proportions of natures and flavors and climatic variables suggest a role for the environment in shaping the properties of CMM. 展开更多
关键词 FLAVOR nature CHINESE materia MEDICA theory of CHINESE medicine property XINJIANG region
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THE MID-INFRARED REFLECTION SIGNATURES OF SEVERAL KINDS OF ROCKS
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作者 谢慧瑗 吕斯骅 金丽芳 《Chinese Science Bulletin》 SCIE EI CAS 1984年第4期525-528,共4页
By using UR-10 automatic double-beam infrared spectrophotometer, measurements of reflection spectra at band from 2 to 25μ were made on the polished planes of rock samples. The results prove to be very satisfactory fo... By using UR-10 automatic double-beam infrared spectrophotometer, measurements of reflection spectra at band from 2 to 25μ were made on the polished planes of rock samples. The results prove to be very satisfactory for the selection of optimal bands and lithologic interpretation of remote sensing pictures. 展开更多
关键词 interpretation rock quartz satisfactory SANDSTONE SEDIMENTARY LIMESTONE MINERALS naturally similarity
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Biomimetic natural biomaterials for tissue engineering and regenerative medicine:new biosynthesis methods,recent advances,and emerging applications 被引量:5
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作者 Shuai Liu Jiang-Ming Yu +11 位作者 Yan-Chang Gan Xiao-Zhong Qiu Zhe-Chen Gao Huan Wang Shi-Xuan Chen Yuan Xiong Guo-Hui Liu Si-En Lin Alec McCarthy Johnson V.John Dai-Xu Wei Hong-Hao Hou 《Military Medical Research》 SCIE CAS CSCD 2024年第1期50-79,共30页
Biomimetic materials have emerged as attractive and competitive alternatives for tissue engineering(TE)and regenerative medicine.In contrast to conventional biomaterials or synthetic materials,biomimetic scaffolds bas... Biomimetic materials have emerged as attractive and competitive alternatives for tissue engineering(TE)and regenerative medicine.In contrast to conventional biomaterials or synthetic materials,biomimetic scaffolds based on natural biomaterial can offer cells a broad spectrum of biochemical and biophysical cues that mimic the in vivo extracellular matrix(ECM).Additionally,such materials have mechanical adaptability,micro-structure interconnectivity,and inherent bioactivity,making them ideal for the design of living implants for specific applications in TE and regenerative medicine.This paper provides an overview for recent progress of biomimetic natural biomaterials(BNBMs),including advances in their preparation,functionality,potential applications and future challenges.We highlight recent advances in the fabrication of BNBMs and outline general strategies for functionalizing and tailoring the BNBMs with various biological and physicochemical characteristics of native ECM.Moreover,we offer an overview of recent key advances in the functionalization and applications of versatile BNBMs for TE applications.Finally,we conclude by offering our perspective on open challenges and future developments in this rapidly-evolving field. 展开更多
关键词 Biomimic SCAFFOLD BIOSYNTHESIS Natural biomaterial Tissue engineering
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Genetic and epigenetic targets of natural dietary compounds as anti-Alzheimer's agents 被引量:2
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作者 Willian Orlando Castillo-Ordoñez Nohelia Cajas-Salazar Mayra Alejandra Velasco-Reyes 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第4期846-854,共9页
Alzheimer’s disease is a progressive neurodegenerative disorder and the most common cause of dementia that principally affects older adults.Pathogenic factors,such as oxidative stress,an increase in acetylcholinester... Alzheimer’s disease is a progressive neurodegenerative disorder and the most common cause of dementia that principally affects older adults.Pathogenic factors,such as oxidative stress,an increase in acetylcholinesterase activity,mitochondrial dysfunction,genotoxicity,and neuroinflammation are present in this syndrome,which leads to neurodegeneration.Neurodegenerative pathologies such as Alzheimer’s disease are considered late-onset diseases caused by the complex combination of genetic,epigenetic,and environmental factors.There are two main types of Alzheimer’s disease,known as familial Alzheimer’s disease(onset<65 years)and late-onset or sporadic Alzheimer’s disease(onset≥65 years).Patients with familial Alzheimer’s disease inherit the disease due to rare mutations on the amyloid precursor protein(APP),presenilin 1 and 2(PSEN1 and PSEN2)genes in an autosomaldominantly fashion with closely 100%penetrance.In contrast,a different picture seems to emerge for sporadic Alzheimer’s disease,which exhibits numerous non-Mendelian anomalies suggesting an epigenetic component in its etiology.Importantly,the fundamental pathophysiological mechanisms driving Alzheimer’s disease are interfaced with epigenetic dysregulation.However,the dynamic nature of epigenetics seems to open up new avenues and hope in regenerative neurogenesis to improve brain repair in Alzheimer’s disease or following injury or stroke in humans.In recent years,there has been an increase in interest in using natural products for the treatment of neurodegenerative illnesses such as Alzheimer’s disease.Through epigenetic mechanisms,such as DNA methylation,non-coding RNAs,histone modification,and chromatin conformation regulation,natural compounds appear to exert neuroprotective effects.While we do not purport to cover every in this work,we do attempt to illustrate how various phytochemical compounds regulate the epigenetic effects of a few Alzheimer’s disease-related genes. 展开更多
关键词 Alzheimer’s disease EPIGENETICS genes METHYLATION natural products
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Synthetic polymers:A review of applications in drilling fluids 被引量:2
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作者 Shadfar Davoodi Mohammed Al-Shargabi +2 位作者 David A.Wood Valeriy S.Rukavishnikov Konstantin M.Minaev 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期475-518,共44页
With the growth of deep drilling and the complexity of the well profile,the requirements for a more complete and efficient exploitation of productive formations increase,which increases the risk of various complicatio... With the growth of deep drilling and the complexity of the well profile,the requirements for a more complete and efficient exploitation of productive formations increase,which increases the risk of various complications.Currently,reagents based on modified natural polymers(which are naturally occurring compounds)and synthetic polymers(SPs)which are polymeric compounds created industrially,are widely used to prevent emerging complications in the drilling process.However,compared to modified natural polymers,SPs form a family of high-molecular-weight compounds that are fully synthesized by undergoing chemical polymerization reactions.SPs provide substantial flexibility in their design.Moreover,their size and chemical composition can be adjusted to provide properties for nearly all the functional objectives of drilling fluids.They can be classified based on chemical ingredients,type of reaction,and their responses to heating.However,some of SPs,due to their structural characteristics,have a high cost,a poor temperature and salt resistance in drilling fluids,and degradation begins when the temperature reaches 130℃.These drawbacks prevent SP use in some medium and deep wells.Thus,this review addresses the historical development,the characteristics,manufacturing methods,classification,and the applications of SPs in drilling fluids.The contributions of SPs as additives to drilling fluids to enhance rheology,filtrate generation,carrying of cuttings,fluid lubricity,and clay/shale stability are explained in detail.The mechanisms,impacts,and advances achieved when SPs are added to drilling fluids are also described.The typical challenges encountered by SPs when deployed in drilling fluids and their advantages and drawbacks are also discussed.Economic issues also impact the applications of SPs in drilling fluids.Consequently,the cost of the most relevant SPs,and the monomers used in their synthesis,are assessed.Environmental impacts of SPs when deployed in drilling fluids,and their manufacturing processes are identified,together with advances in SP-treatment methods aimed at reducing those impacts.Recommendations for required future research addressing SP property and performance gaps are provided. 展开更多
关键词 Synthetic versus natural polymers Nanopolymers Drilling fluid additives LUBRICITY Clay swelling Hole cleaning
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Facile synthesis of hierarchical NaX zeolite from natural kaolinite for efficient Knoevenagel condensation 被引量:2
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作者 Wen Xiao Peng Dong +6 位作者 Chan Wang Jingdong Xu Tiesen Li Haibo Zhu Tinghai Wang Renwei Xu Yuanyuan Yue 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第1期75-84,共10页
Zeolite catalysts have found extensive applications in the synthesis of various fine chemicals.However,the micropores of zeolites impose diffusion limitations on bulky molecules,greatly reducing the catalytic efficien... Zeolite catalysts have found extensive applications in the synthesis of various fine chemicals.However,the micropores of zeolites impose diffusion limitations on bulky molecules,greatly reducing the catalytic efficiency.Herein,we explore an economic and environmentally friendly method for synthesizing hierarchical NaX zeolite that exhibits improved catalytic performance in the Knoevenagel condensation reaction for producing the useful fine chemical 2-cyano-3-phenylacrylate.The synthesis was achieved via a low-temperature activation of kaolinite and subsequent in-situ transformation strategy without any template or seed.Systematic characterizations reveal that the synthesized NaX zeolite has both intercrystalline and intra-crystalline mesopores,smaller crystal size,and larger external specific surface area compared to commercial NaX zeolite.Detailed mechanism investigations show that the inter-crystalline mesopores are generated by stacking smaller crystals formed from in-situ crystallization of the depolymerized kaolinite,and the intra-crystalline mesopores are inherited from the pores in the depolymerized kaolinite.This synthesis strategy provides an energy-saving and effective way to construct hierarchical zeolites,which may gain wide applications in fine chemical manufacturing. 展开更多
关键词 Hierarchical NaX zeolite Template-free synthesis Natural kaolinite Knoevenagel condensation
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Mechanical Modeling and Analysis of Stability Deterioration of Production Well During Marine Hydrate Depressurization Production 被引量:1
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作者 SUN Huan-zhao CHANG Yuan-jiang +4 位作者 SUN Bao-jiang WANG Kang CHEN Guo-ming LI Hao DAI Yong-guo 《China Ocean Engineering》 SCIE EI CSCD 2024年第2期338-351,共14页
Different from oil and gas production,hydrate reservoirs are shallow and unconsolidated,whose mechanical properties deteriorate with hydrate decomposition.Therefore,the formations will undergo significant subsidence d... Different from oil and gas production,hydrate reservoirs are shallow and unconsolidated,whose mechanical properties deteriorate with hydrate decomposition.Therefore,the formations will undergo significant subsidence during depressurization,which will destroy the original force state of the production well.However,existing research on the stability of oil and gas production wells assumes the formation to be stable,and lacks consideration of the force exerted on the hydrate production well by formation subsidence caused by hydrate decomposition during production.To fill this gap,this paper proposes an analytical method for the dynamic evolution of the stability of hydrate production well considering the effects of hydrate decomposition.Based on the mechanical model of the production well,the basis for stability analysis has been proposed.A multi-field coupling model of the force state of the production well considering the effect of hydrate decomposition and formation subsidence is established,and a solver is developed.The analytical approach is verified by its good agreement with the results from the numerical method.A case study found that the decomposition of hydrate will increase the pulling-down force and reduce the supporting force,which is the main reason for the stability deterioration.The higher the initial hydrate saturation,the larger the reservoir thickness,and the lower the production pressure,the worse the stability or even instability.This work can provide a theoretical reference for the stability maintaining of the production well. 展开更多
关键词 natural gas hydrate production well depressurization production formation deformation stability deterioration
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Predicting the friction angle of clays using a multi-layer perceptron neural network enhanced by yeo-johnson transformation and coral reefs optimization 被引量:1
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作者 Libing Yang Trung Nguyen-Thoi Trung-Tin Tran 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第10期3982-4003,共22页
The accurate prediction of the friction angle of clays is crucial for assessing slope stability in engineering applications.This study addresses the importance of estimating the friction angle and presents the develop... The accurate prediction of the friction angle of clays is crucial for assessing slope stability in engineering applications.This study addresses the importance of estimating the friction angle and presents the development of four soft computing models:YJ-FPA-MLPnet,YJ-CRO-MLPnet,YJ-ACOC-MLPnet,and YJCSA-MLPnet.First of all,the Yeo-Johnson(YJ)transformation technique was used to stabilize the variance of data and make it more suitable for parametric statistical models that assume normality and equal variances.This technique is expected to improve the accuracy of friction angle prediction models.The friction angle prediction models then utilized multi-layer perceptron neural networks(MLPnet)and metaheuristic optimization algorithms to further enhance performance,including flower pollination algorithm(FPA),coral reefs optimization(CRO),ant colony optimization continuous(ACOC),and cuckoo search algorithm(CSA).The prediction models without the YJ technique,i.e.FPA-MLPnet,CRO-MLPnet,ACOC-MLPnet,and CSA-MLPnet,were then compared to those with the YJ technique,i.e.YJ-FPA-MLPnet,YJ-CRO-MLPnet,YJ-ACOC-MLPnet,and YJ-CSA-MLPnet.Among these,the YJ-CRO-MLPnet model demonstrated superior reliability,achieving an accuracy of up to 83%in predicting the friction angle of clay in practical engineering scenarios.This improvement is significant,as it represents an increase from 1.3%to approximately 20%compared to the models that did not utilize the YJ transformation technique. 展开更多
关键词 Natural hazards Slope stability Friction angle CLAY Soft computing models Geotechnical engineering
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Simulation of the Ecosystem Productivity Responses to Aerosol Diffuse Radiation Fertilization Effects over the Pan-Arctic during 2001–19 被引量:1
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作者 Zhiding ZHANG Xu YUE +3 位作者 Hao ZHOU Jun ZHU Yadong LEI Chenguang TIAN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第1期84-96,共13页
The pan-Arctic is confronted with air pollution transported from lower latitudes.Observations have shown that aerosols help increase plant photosynthesis through the diffuse radiation fertilization effects(DRFEs).Whil... The pan-Arctic is confronted with air pollution transported from lower latitudes.Observations have shown that aerosols help increase plant photosynthesis through the diffuse radiation fertilization effects(DRFEs).While such DRFEs have been explored at low to middle latitudes,the aerosol impacts on pan-Arctic ecosystems and the contributions by anthropogenic and natural emission sources remain less quantified.Here,we perform regional simulations at 0.2o×0.2ousing a well-validated vegetation model(Yale Interactive terrestrial Biosphere,YIBs)in combination with multi-source of observations to quantify the impacts of aerosol DRFEs on the net primary productivity(NPP)in the pan-Arctic during 2001-19.Results show that aerosol DRFEs increase pan-Arctic NPP by 2.19 Pg C(12.8%)yr^(-1)under clear-sky conditions,in which natural and anthropogenic sources contribute to 8.9% and 3.9%,respectively.Under all-sky conditions,such DRFEs are largely dampened by cloud to only 0.26 Pg C(1.24%)yr^(-1),with contributions of 0.65% by natural and 0.59% by anthropogenic species.Natural aerosols cause a positive NPP trend of 0.022% yr^(-1)following the increased fire activities in the pan-Arctic.In contrast,anthropogenic aerosols induce a negative trend of-0.01% yr^(-1)due to reduced emissions from the middle latitudes.Such trends in aerosol DRFEs show a turning point in the year of 2007 with more positive NPP trends by natural aerosols but negative NPP trends by anthropogenic aerosols thereafter.Though affected by modeling uncertainties,this study suggests a likely increasing impact of aerosols on terrestrial ecosystems in the pan-Arctic under global warming. 展开更多
关键词 diffuse radiation fertilization effects anthropogenic aerosols natural aerosols pan-Arctic net primary productivity
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