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教材心理化? 杜威作品中译本对“subject matter”的误译及其影响
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作者 丁道勇 《北京大学教育评论》 CSSCI 北大核心 2023年第4期85-109,188,共26页
把subject matter译作“教材”,使之对等于教学过程中使用的包括教科书在内的各类教学材料,是杜威作品中译本中反复出现的一个译法。通过对杜威作品的中、英文本进行相关比对,可知这是一个误译。在杜威作品中,subject matter指的是“学... 把subject matter译作“教材”,使之对等于教学过程中使用的包括教科书在内的各类教学材料,是杜威作品中译本中反复出现的一个译法。通过对杜威作品的中、英文本进行相关比对,可知这是一个误译。在杜威作品中,subject matter指的是“学科内容”,是各门学科提供的事实和法则,不是教学过程中使用的教科书等教材。“教材心理化”这个中文表达,是subject matter误译的一个直接结果。对这一中文表达的内涵与影响的考察,进一步印证了上述研究发现。Subject matter是杜威反复提及的一个概念,是联系其教育哲学与哲学重建工作的关键词。对subject matter的误译,造成了有关杜威理论的一系列误解。 展开更多
关键词 subject matter 教材 教材心理化 杜威
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In vivo 3-photon fluorescence microscopy of white matter in mouse brain excited at the 1700 nm window 被引量:1
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作者 Jie Huang Jincheng Zhong +3 位作者 Shen Tong Yingxian Zhang Ping Qiu Ke Wang 《Journal of Innovative Optical Health Sciences》 SCIE EI CSCD 2024年第5期81-87,共7页
White matter,a densely packed collection of myelinated axons,plays an essential part in neural networks.With high spatial resolution and deep penetration,multi-photon microscopy(MPM)is promising for white matter imagi... White matter,a densely packed collection of myelinated axons,plays an essential part in neural networks.With high spatial resolution and deep penetration,multi-photon microscopy(MPM)is promising for white matter imaging in animal models in vivo.The third harmonic generation(THG)signal can be generated from white matter,but the bottom part of the white matter layer generates weak THG due to its high scattering.Here,we demonstrate an in vivo labeling and imaging technology,capable of visualizing the white matter layer in the mouse brain,combining°uorescence labeling with MitoTracker Red and three-photon°uorescence(3PF)microscopy excited at the 1700 nm window.3PF signals are several times higher than THG signals,resulting in deeper imaging of the white matter layer with the former.Our results indicate that 3PF microscopy is a promising technology for white matter imaging in the deep brain in vivo. 展开更多
关键词 Three-photon microscopy white matter MYELIN MitoTracker Red
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Ethyl acetate fraction of Sargassum pallidum extract attenuates particulate matter-induced oxidative stress and inflammation in keratinocytes and zebrafish 被引量:1
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作者 Wook Chul Kim Ji-Won Park +3 位作者 Bohyun Yun WonWoo Lee Kyung-Min Choi Seung-Hong Lee 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2024年第4期137-146,共10页
Objective:To evaluate the effect of the ethyl acetate fraction derived from Sargassum pallidum extract against particulate matter(PM)-induced oxidative stress and inflammation in HaCaT cells and zebrafish.Methods:HaCa... Objective:To evaluate the effect of the ethyl acetate fraction derived from Sargassum pallidum extract against particulate matter(PM)-induced oxidative stress and inflammation in HaCaT cells and zebrafish.Methods:HaCaT cells and zebrafish were used to evaluate the protective effects of the ethyl acetate fraction of Sargassum pallidum extract against PM-induced oxidative stress and inflammation.The production of nitric oxide(NO),intracellular ROS,prostaglandin E_(2)(PGE_(2)),and pro-inflammatory cytokines,and the expression levels of COX-2,iNOS,and NF-κB were evaluated in PM-induced HaCaT cells.Furthermore,the levels of ROS,NO,and lipid peroxidation were assessed in the PM-exposed zebrafish model.Results:The ethyl acetate fraction of Sargassum pallidum extract significantly decreased the production of NO,intracellular ROS,and PGE_(2) in PM-induced HaCaT cells.In addition,the fraction markedly suppressed the levels of pro-inflammatory cytokines and inhibited the expression levels of COX-2,iNOS,and NF-κB.Furthermore,it displayed remarkable protective effects against PM-induced inflammatory response and oxidative stress,represented by the reduction of NO,ROS,and lipid peroxidation in zebrafish.Conclusions:The ethyl acetate fraction of Sargassum pallidum extract exhibits a protective effect against PM-induced oxidative stress and inflammation both in vitro and in vivo and has the potential as a candidate for the development of pharmaceutical and cosmeceutical products. 展开更多
关键词 Particulate matter INFLAMMATION Oxidative stress Sargassum pallidum Ethyl acetate fraction ZEBRAFISH
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Multiple enrichment mechanisms of organic matter in the Fengcheng Formation of Mahu Sag,Junggar Basin,NW China 被引量:1
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作者 GONG Deyu LIU Zeyang +4 位作者 HE Wenjun ZHOU Chuanmin QIN Zhijun WEI Yanzhao YANG Chun 《Petroleum Exploration and Development》 SCIE 2024年第2期292-306,共15页
Based on core and thin section data,the source rock samples from the Fengcheng Formation in the Mahu Sag of the Junggar Basin were analyzed in terms of zircon SIMS U-Pb geochronology,organic carbon isotopic compositio... Based on core and thin section data,the source rock samples from the Fengcheng Formation in the Mahu Sag of the Junggar Basin were analyzed in terms of zircon SIMS U-Pb geochronology,organic carbon isotopic composition,major and trace element contents,as well as petrology.Two zircon U-Pb ages of(306.0±5.2)Ma and(303.5±3.7)Ma were obtained from the first member of the Fengcheng Formation.Combined with carbon isotopic stratigraphy,it is inferred that the depositional age of the Fengcheng Formation is about 297-306 Ma,spanning the Carboniferous-Permian boundary and corresponding to the interglacial period between C4 and P1 glacial events.Multiple increases in Hg/TOC ratios and altered volcanic ash were found in the shale rocks of the Fengcheng Formation,indicating that multiple phases of volcanic activity occurred during its deposition.An interval with a high B/Ga ratio was found in the middle of the second member of the Fengcheng Formation,associated with the occurrence of evaporite minerals and reedmergnerite,indicating that the high salinity of the water mass was related to hydrothermal activity.Comprehensive analysis suggests that the warm and humid climate during the deposition of Fengcheng Formation is conducive to the growth of organic matter such as algae and bacteria in the lake,and accelerates the continental weathering,driving the input of nutrients.Volcanic activities supply a large amount of nutrients and stimulate primary productivity.The warm climate and high salinity are conducive to water stratification,leading to water anoxia that benefits organic matter preservation.The above factors interact and jointly control the enrichment of organic matter in the Fengcheng Formation of Mahu Sag. 展开更多
关键词 Junggar Basin Mahu Sag Fengcheng Formation organic matter interglacial period VOLCANISM paleo-salinity paleo-environmental evolution
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Exploring the Dual Subjectivity of Kindergarten's Self-made Play and Teaching Aids Activities from the Perspective of Children's Play Development in China 被引量:1
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作者 Yuwei Zhao 《教育技术与创新》 2024年第1期1-9,共9页
The joint development of teachers and young children is the basis for promoting the development of high-quality preschool education in the new era,and encouraging early childhood teachers to make playthings according ... The joint development of teachers and young children is the basis for promoting the development of high-quality preschool education in the new era,and encouraging early childhood teachers to make playthings according to local conditions is both the fine tradition of China's early childhood education and the direct orientation of China's preschool education policy.Homemade play and teaching aids are some of the methods often used in kindergartens,which skillfully combine young children's daily life objects with toys and early childhood teaching,not only enriching the collective activities of young children but also cultivating children's abilities in various aspects.Kindergarten homemade"play and teaching aids"for early childhood teachers and children have their special educational significance and value,therefore,this paper is based on the children and teachers double subject basis,discussing the homemade"play and teaching aids"for children and teachers of the double subject meanings,and puts forward the realization of the This paper discusses the double-subjective meaning of homemade teaching aids for children and teachers on the basis of the double-subjective foundation of children and teachers,and puts forward specific suggestions for realizing the double-subjectivity of kindergarten homemade teaching aids to enrich the theoretical value and practical significance of homemade teaching aids,to provide theoretical references and support for the relevant staff. 展开更多
关键词 Self-made playthings Double subjectivity KINDERGARTEN China
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Acute Coronary Syndrome of Young Subjects at the Luxembourg Mother-Child University Hospital in Bamako
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作者 Mamadou Toure Mariam Dagnogo +15 位作者 Massama Konate Mariam Sako Daouda Fofana Hamma Sankare Almou A. Diall Modibo Doumbia Baba I. Diarr Mady Sow Abdoul Wahhab Terra Coumba A. Thiam Boubacar Sonfo Boubacar Diarra Asmaou Keita Ousmane Traore Hamidou O. Ba Ichaka Menta 《World Journal of Cardiovascular Diseases》 CAS 2024年第3期157-165,共9页
Introduction: Acute coronary syndrome is often the first event of coronary disease of young subjects. Objective: To study sociodemographic, clinical, paraclinical, therapeutic and evolutionary aspects of acute coronar... Introduction: Acute coronary syndrome is often the first event of coronary disease of young subjects. Objective: To study sociodemographic, clinical, paraclinical, therapeutic and evolutionary aspects of acute coronary syndrome of young subjects. Patients and Methods: Descriptive cross-sectional study with prospective recruitment from October 01, 2020 to March 31, 2022. Were included all patients admitted for acute coronary syndrome whose age was less or equal to 45 years and who had undergone coronary angiography at the Mother-Child University Hospital on Luxembourg from Bamako. Results: During the study period, we collected 60 patient files out of 198. These 60 patient files met our inclusion criteria. Hospital frequency was 30.30%. Average age of patients was 40.43 ± 3.9 years. Sex ratio M/F was 5.3. Main cardiovascular risk factor was smoking tobacco (23.42%), followed by dyslipidemia (13.92%). Functional signs were dominated by angina 62% followed by dyspnea 25.3%. Persistent ST-segment elevation on electrocardiogram was present in 76.4%. Left ventricular systolic dysfunction was present in 26.5%. Time to first medical contact was more than 12 hours in 62.7% of cases. Radial approach was adopted in 94% of cases. Coronary angiography was pathological in 85% (n = 51) of cases. Lesions were single-vessel disease in 47.1% and culprit artery was anterior interventricular in 51% of cases. Dual anti-platelet aggregation was aspirin and ticagrelor in 91.8% of cases. Angioplasty was performed in all patients who had significant abnormalities at coronary angiography. In-hospital mortality was 3.9%. Conclusion: Acute coronary syndromes exist in young Africans with a male predominance. Main cardiovascular risk factor is smoking tobacco. Coronary lesions are single vessel disease in the majority of case. Most of patients meet medical team after 12 hours. Time to first medical contact is a main challenge in our country. 展开更多
关键词 Acute Coronary Syndrome Young subjects Coronary Angiography CHU Luxembourg BAMAKO
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A pressure-sensitive rheological origin of high friction angles of granular matter observed in NASA–MGM project
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作者 程晓辉 肖世泽 +2 位作者 杨森 赵乃峰 Alex Sixie Cao 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第6期559-567,共9页
An abnormally high peak friction angle of Ottawa sand was observed in(National Aeronautics and Space Administration) NASA–(Mechanics of Granular Materials) MGM tests in microgravity conditions on the space shuttle. P... An abnormally high peak friction angle of Ottawa sand was observed in(National Aeronautics and Space Administration) NASA–(Mechanics of Granular Materials) MGM tests in microgravity conditions on the space shuttle. Previous investigations have been unsuccessful in providing a constitutive insight into this behavior of granular materials under extremely low effective stress conditions. Here, a recently proposed unified constitutive model for transient rheological behavior of sand and other granular materials is adopted for the analytical assessment of high peak friction angles. For the first time, this long-eluded behavior of sand is attributed to a hidden rheological transition mechanism, that is not only rate-sensitive, but also pressure-sensitive. The NASA–MGM microgravity conditions show that shear-tests of sand can be performed under abnormally low confining stress conditions. The pressure-sensitive behavior of granular shearing that is previously ignored is studied based on the μ(I) rheology and its variations. Comparisons between the model and the NASA microgravity tests demonstrate a high degree of agreement. The research is highly valid for pressure-sensitive and rate-dependent problems that occur during earthquakes, landslides, and space exploration. 展开更多
关键词 granular matter MICROGRAVITY pressure-sensitive NASA–MGM
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Disorder-to-order transition induced by spontaneous cooling regulation in robotic active matter
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作者 侯帅旭 王高 +5 位作者 马星宇 汪楚云 王鹏 陈怀城 刘雳宇 王璟 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第7期96-103,共8页
In classical matter systems, typical phase-transition phenomena usually stem from changes in state variables, such as temperature and pressure, induced by external regulations such as heat transfer and volume adjustme... In classical matter systems, typical phase-transition phenomena usually stem from changes in state variables, such as temperature and pressure, induced by external regulations such as heat transfer and volume adjustment. However, in active matter systems, the self-propulsion nature of active particles endows the systems with the ability to induce unique collectivestate transitions by spontaneously regulating individual properties to alter the overall states. Based on an innovative robot-swarm experimental system, we demonstrate a field-driven active matter model capable of modulating individual motion behaviors through interaction with a recoverable environmental resource field by the resource perception and consumption.In the simulated model, by gradually reducing the individual resource-conversion coefficient over time, this robotic active matter can spontaneously decrease the overall level of motion, thereby actively achieving a regulation behavior like the cooling-down control. Through simulation calculations, we discover that the spatial structures of this robotic active matter convert from disorder to order during this process, with the resulting ordered structures exhibiting a high self-adaptability on the geometry of the environmental boundaries. 展开更多
关键词 active matter robot swarm collective-state transitions environmental self-adaptability
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The Structure of Gravity Funnels and Stability Considerations of Matter in SI Units
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作者 Tobias Bartusch 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第1期71-81,共11页
This article describes an extension of the theory of vortices to electromagnetic types with a start point from known fluid systems. From this, properties of gravity-generating objects (particles and black holes) can b... This article describes an extension of the theory of vortices to electromagnetic types with a start point from known fluid systems. From this, properties of gravity-generating objects (particles and black holes) can be derived, which can also describe their possible interior. This also leads to questions about stability, which are then addressed and ultimately lead to considerations of black holes and their possible internal structure. The results fit into the observable areas and can also be directly verified because they were analytically calculated in SI units. 展开更多
关键词 Black Hole Dark matter Electromagnetic GRAVITY SINGULARITY VORTEX
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Application of proton magnetic resonance spectroscopy in metabolic alterations of prefrontal white and gray matter in depression adolescents
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作者 Ying Zou Yu-Qin Wu +2 位作者 Yao-Jing Han Xiao-Ming He Jiang Zhao 《World Journal of Psychiatry》 SCIE 2024年第11期1652-1660,共9页
BACKGROUND Cases of depression among adolescents are gradually increasing.The study of the physiological basis of cognitive function from a biochemical perspective has therefore been garnering increasing attention.Dep... BACKGROUND Cases of depression among adolescents are gradually increasing.The study of the physiological basis of cognitive function from a biochemical perspective has therefore been garnering increasing attention.Depression has been hypothesized to be associated with the brain biochemical metabolism of the anterior cingulate gyrus,frontal lobe white matter,and the thalamus.AIM To explore the application of proton magnetic resonance spectroscopy(1H-MRS)in the metabolic alterations in the prefrontal white matter(PWM)and gray matter(GM)in adolescents with depression.METHODS 1H-MRS was performed for semi-quantitative analysis of the biochemical metabolites N-acetylaspartate(NAA),choline(Cho)complexes,creatine(Cr),and myoinositol(mI)in bilateral PWM,anterior cingulate GM,and thalami of 31 adolescent patients with depression(research group)and 35 healthy adolescents(control group),and the NAA/Cr,Cho/Cr,and mI/Cr ratios were calculated.Meanwhile,Hamilton Depression Scale(HAMD)and Wechsler Memory Scale were used to assess the degree of depression and memory function in all adolescents.The correlation of brain metabolite levels with scale scores was also analyzed.RESULTS The research group had markedly higher HAMD-24 scores and lower memory quotient(MQ)compared with the control group(P<0.05).Adolescents with depression were found to have lower bilateral PWM NAA/Cr and Cho/Cr ratios compared with healthy adolescents(P<0.05).The mI/Cr ratios were found to be similar in both groups(P>0.05).The bilateral anterior cingulate GM NAA/Cr,Cho/Cr,and mI/Cr also did not demonstrate marked differences(P>0.05).No statistical inter-group difference was determined in NAA/Cr of the bilateral thalami(P>0.05),while bilateral thalamic Cho/Cr and mI/Cr were reduced in teenagers with depression compared with healthy adolescents(P<0.05).A significant negative correlation was observed between the HAMD-24 scores in adolescents with depression with bilateral PWM NAA/Cr and Cho/Cr and were inversely linked to bilateral thalamic Cho/Cr and mI/Cr(P<0.05).In adolescents with depressions,MQ positively correlated with right PWH NAA/Cr,left PWH Cho/Cr,and bilateral thalamic Cho/Cr and mI/Cr.CONCLUSION PWM and thalamic metabolic abnormalities might influence teen depression,and the reduction in bilateral PWM NAA/Cr and Cho/Cr could be related to the neuropathology of adolescents with depression suffering from memory impairment.There exists a possibility of dysfunction of nerve cell membrane phospholipids in the thalami of adolescent patients with depression. 展开更多
关键词 Proton magnetic resonance spectroscopy Adolescent depression Prefrontal white matter Anterior cingulate gray matter METABOLISM
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Distribution and sources of sedimentary organic matter in different aquaculture areas of northeastern Zhanjiang Bay using stable carbon and nitrogen isotopes
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作者 Fengxia Zhou Shuangling Wang +8 位作者 Han Fang Jiani He Liang Ye Zhaohai Ding Cuiting Li Fajin Chen Xuan Lu Chunqing Chen Yafei Meng 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第6期38-48,共11页
Zhanjiang Bay is a major aquaculture area in China with many types of mariculture products(such as oysters,fish,and shrimp).The culture area and shrimp output in Zhanjiang Bay are ranked first in China.We investigated... Zhanjiang Bay is a major aquaculture area in China with many types of mariculture products(such as oysters,fish,and shrimp).The culture area and shrimp output in Zhanjiang Bay are ranked first in China.We investigated the total organic carbon(TOC),total nitrogen(TN),TOC/TN ratio,and stable isotopes(δ^(13)C and δ^(15)N) of the fish and shrimp feed,fish and shrimp feces,and sedimentary organic matter(SOM) in and around different aquaculture areas of northeastern Zhanjiang B ay to study the impact of aquaculture activities on SOM.The average TOC contents of fish and shrimp feed were 39.20%±0.91% and 39.29%±0.21%,respectively.The average TOC content in the surface sediments of the oyster culture area,the mixed(fish and shrimp) culture area,and the cage fish farm area were 0.66%,0.88%±0.10%,and 0.58%±0.19%,respectively,which may indicate that mixed culture had a greater impact on SOM.The relatively high TOC and TN contents and relatively low TOC/TN ratios,and δ^(15)N values in the upper layer of the core sediment in the mixed culture area could also support the significant influence of mixed culture.The average δ^(13)C and δ^(15)N values of fish and shrimp feed were -20.6‰±2.2‰ and 1.8‰±1.2‰,respectively,which were different from the isotopic values of SOM in the study area.δ^(13)C and δ^(15)N values for SOM in different aquaculture areas were different from those of nearby reference stations,probably reflecting the influence of aquaculture.The δ^(13)C and δ^(15)N values in the oyster culture area(-25.9‰ and6.0‰,respectively) seemed to have reduced δ^(13)C and enriched δ^(15)N relative to those of the reference station(-24.6‰ and 5.8‰,respectively).This may reflect the influence of organic matter on oyster culture.The δ^(15)N value of the station in the mixed culture area(7.1‰±0.4‰) seemed to be relatively enriched in δ^(15)N relative to that of the reference station(6.6‰).Sedimentation and the subsequent degradation of organic matter from mixed cultures may have contributed to this phenomenon.The surface sediment at the cage fish farm area seemed to be affected by fish feces and primary production based on the indication of δ^(13)C and δ^(15)N values.The sediment core at the mixed culture region(NS6) had lower TOC/TN ratios and more positive δ^(13)C and δ^(15)N values than the sediment core at the oyster culture area,suggesting a higher proportionate contribution of marine organic matter in the mixed culture area.In summary,oyster culture,mixed culture,and cage fish culture in northeastern Zhanjiang Bay had a certain degree of impact on SOM,and mixed culture had more significant influences on SOM based on the high TOC contents and the significant vertical variations of TOC/TN ratio and δ^(15)N value in the sediment of this area.This study provides new insights into the impact of aquaculture activities on SOM content. 展开更多
关键词 sedimentary organic matter AQUACULTURE stable isotopes SOURCES Zhanjiang Bay
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Straw mulching alters the composition and loss of dissolved organic matter in farmland surface runoff by inhibiting the fragmentation of soil small macroaggregates
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作者 Shanshan Cai Lei Sun +7 位作者 Wei Wang Yan Li Jianli Ding Liang Jin Yumei Li Jiuming Zhang Jingkuan Wang Dan Wei 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第5期1703-1717,共15页
Straw mulching is a widespread practice for reducing the soil carbon loss caused by erosion.However,the effects of straw mulching on dissolved organic matter(DOM)runoff loss from black soil are not well studied.How st... Straw mulching is a widespread practice for reducing the soil carbon loss caused by erosion.However,the effects of straw mulching on dissolved organic matter(DOM)runoff loss from black soil are not well studied.How straw mulching affects the composition and loss of runoff DOM by changing soil aggregates remains largely unclear.Here,a straw mulching treatment was compared to a no mulching treatment(as a control)on sloping farmland with black soil erosion in Northeast China.We divided the soil into large macroaggregates(>2 mm),small macroaggregates(0.25-2 mm),and microaggregates(<0.25 mm).After five rain events,the effects of straw mulching on the concentration(characterized by dissolved organic carbon(DoC)and composition(analyzed by fluorescence spectroscopy)of runoff and soil aggregate DOM were studied.The results showed that straw mulching reduced the runoff amount by 54.7%.Therefore,although straw mulching increased the average DOc concentration in runoff,it reduced the total runoff DOM loss by 48.3%.The composition of runoff DOM is similar to that of soil,as both contain humic-like acid and protein-like components.With straw mulching treatment,the protein-like components in small macroaggregates accumulated and the protein-like components in runoff declined with rain events.Fluorescence spectroscopy technology may help in understanding the hydrological paths of rain events by capturing the dynamic changes of runoff and soil DOM characteristics.A variation partitioning analysis(VPA)indicated that the DOM concentration and composition of microaggregates explained 68.2%of the change in runoff DOM from no mulching plots,while the change in runoff DOM from straw mulching plots was dominated by small macroaggregates at a rate of 55.1%.Taken together,our results demonstrated that straw mulching reduces the fragmentation of small macroaggregates and the loss of microaggregates,thus effecting DOM compositions in soil and reducing the DOM loss in runoff.These results provide a theoretical basis for reducing carbon loss in sloping farmland. 展开更多
关键词 dissolved organic matter black soil surface runoff AGGREGATES fluorescence spectrum
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Solving the Conundrum of Dark Matter and Dark Energy in Galaxy Clusters
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作者 Manuel Abarca 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第4期1785-1805,共21页
This paper develops the Dark Matter by Quantum Gravitation theory, DMbQG theory hereafter, in clusters of galaxies in the cosmologic model ΛCDM of the Universe. Originally this theory was developed by the author for ... This paper develops the Dark Matter by Quantum Gravitation theory, DMbQG theory hereafter, in clusters of galaxies in the cosmologic model ΛCDM of the Universe. Originally this theory was developed by the author for galaxies, especially using MW and M31 rotation curves. An important result got by the DMbQG theory is that the total mass associated to a galactic halo depend on the square root of radius, being its dominion unbounded. Apparently, this result would be absurd because of divergence of the total mass. As the DE is negligible at galactic scale, it is needed to extend the theory to clusters in order to study the capacity of DE to counterbalance to DM. Thanks this property, the DMbQG theory finds unexpected theoretical results. In this work, it is defined, the total mass as baryonic matter plus DM and the gravitating mass as the addition of the total mass plus the negative mass associated to dark energy. In clusters it is defined the zero gravity radius (RZG hereafter) as the radius needed by the dark energy to counterbalance the total mass. It has been found that the ratio RZG/RVIRIAL ≈ 7.3 and its Total mass associated at RZG is ≈2.7 MVIRIAL. In addition, it has been calculated that the sphere with the extended halo radius RE = 1.85 RZG has a ratio DM density versus DE density equal to 3/7 and its total mass associated at RE is ≈3.6 MVIRIAL. This works postulates that the factor 3.6 may equilibrate perfectly the strong imbalance between the Local mater density parameter (0.08) versus the current Global matter density one (0.3). Currently, this fact is a big conundrum in cosmology, see chapter 7. Also it has been found that the zero velocity radius, RZV hereafter, i.e. the cluster border because of the Hubble flow, is ≈0.6 RZG and its gravitating mass is ≈ 1.5 MVIR. By derivation of gravitating mass function, it is calculated that at 0.49 RZG, this function reaches its maximum whose value is ≈1.57 MVIR. Throughout the paper, some of these results have been validated with recent data published for the Virgo cluster. As Virgo is the nearest big cluster, it is the perfect benchmark to validate any new theory about DM and DE. These new theoretical findings offer to scientific community a wide number of tests to validate or reject the theory. The validation of DMbQG theory would mean to know the nature of DM that at the present, it is an important challenge for the astrophysics science. 展开更多
关键词 Dark matter Dark Energy Galaxy Clusters Quantum Gravitation
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A Dark Matter Theory by Quantum Gravitation for Galaxies and Clusters
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作者 Manuel Abarca 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第4期1749-1784,共36页
This paper develops an original theory of dark matter in the current ΛCDM framework, whose main hypothesis is that DM is generated by the own gravitational field, according to an unknown quantum gravitational phenome... This paper develops an original theory of dark matter in the current ΛCDM framework, whose main hypothesis is that DM is generated by the own gravitational field, according to an unknown quantum gravitational phenomenon. This work is the best version of the theory, which I have been developing and publishing since 2014. The hypothesis of DM by quantum gravitation, DMbQG hereafter, has two main consequences: the first one is that the law of DM generation has to be the same, in the halo region, for all the galaxies and the second one is that the haloes are unbounded, so the total DM goes up without limit as the gravitational field is unbounded as well. The first one consequence is backed by the fact that M31 and MW has a fitted function with the same power exponent for the rotation curve at the halo region and both giant galaxies are the only ones whose rotation curves at the halo region may be studied with accuracy. This paper is firstly developed all the theory with M31 rotation curve data up to Chapter 9. The most important formula of the theory is the called Direct mass, which calculates the total mass at a specific radius into the halo region. Chapter 10 is dedicated to apply the theory to Milky Way, it is calculated its total mass at different radius into the halo and such results have been validated successfully using the data of masses at different radius published by two researcher teams. In Chapter 11, it is calculated the direct mass for the Local Group, and it is shown how the DMbQG theory is able to calculate the total mass at 770 kpc, that the dynamical methods estimate to be 5×1012MΘ. In Chapter 12, it is shown a method to estimate the Direct mass formula for a cluster of galaxies, using only its virial mass and virial radius. By this method, it is estimated the parameter a2 of the Local Group, which match with the one calculated in previous chapter by a different method. Also are calculated the parameters a2 associated to Virgo and Coma clusters. In Chapter 13, it is demonstrated how the DE is able to counterbalance the DM at cluster scale, as the Direct mass grows up with the square root of radius whereas the DE grows up with the cubic power. The chapter is an introduction to the DMbQG theory for cluster of galaxies, which has been developed fully by the author in other works. This theory aims to be a powerful method to study DM in the halo region of galaxies and cluster of galaxies and conversely the measures in galaxies and clusters offer the possibility to validate the theory. 展开更多
关键词 Dark matter Dark Energy GALAXIES Local Group of Galaxies CLUSTERS
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Biogeochemistry of sedimentary organic matter in the Yongjiang River estuary in the southern part of Hangzhou Bay,China,since the Late Pleistocene
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作者 Dongqin HUANG Xiaolong LI +6 位作者 Zilong LI Pei Sun LOH Jianxiong HU Jianfang CHEN Yuan-Pin CHANG Chin-Wen YANG Qin GAO 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第3期772-786,共15页
A sediment core(YJK19-02)collected from the southern outlet of Hangzhou Bay near the Yongjiang River estuary in East China was analyzed for grain size,lignin,bulk elemental composition,stable carbon isotope,and rare e... A sediment core(YJK19-02)collected from the southern outlet of Hangzhou Bay near the Yongjiang River estuary in East China was analyzed for grain size,lignin,bulk elemental composition,stable carbon isotope,and rare earth elements(REEs)to determine the sources and diagenesis of sedimentary organic matter(OM)of the estuary and adjacent areas since the Late Pleistocene.δ^(13)C values(-24.80‰–-23.60‰),total organic carbon/total nitrogen(TOC/TN)molar ratios(8.00–12.14),and light rare earth element/heavy rare earth element ratios(LREE/HREE=8.34–8.91)revealed the predominance of terrestrial sources of OM,mainly from the Changjiang(Yangtze)River.The lignin parameters of syringyl/vanillyl(S/V=0.20–0.73)and cinnamyl/vanillyl(C/V=0.03–0.19)ratios indicate the predominance of nonwoody angiosperms,and the vanillic acid/vanillin ratios[(Ad/Al)_(V)=0.32–1.57]indicate medium to high degrees of lignin degradation.An increasing trend ofΛ(total lignin in mg/100-mg OC)values from ca.14500 a BP to ca.11000 a BP reflected the increase in temperature during the Late Pleistocene.However,a time lag effect of temperature on vegetation abundance was also revealed.The relatively higher and stableΛvalues correspond to the higher temperature during the mid-Holocene from ca.8500 a BP to ca.4500 a BP.Λvalues decreased from ca.4000 a BP to the present,corresponding to historical temperature fluctuations during this time.Our results show that the vegetation abundance in the Yongjiang River Basin since the Late Pleistocene was related to the temperature fluctuation duo to climate change. 展开更多
关键词 Yongjiang River estuary sedimentary organic matter LIGNIN environmental change Late Pleistocene
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Relationship Between Individuals’Epidemic Risk Perception Within Living Space and Subjective Well-Being:Empirical Evidence from China after the First Wave of COVID-19
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作者 SONG Jiangyu ZHOU Suhong +1 位作者 KWAN Mei-Po ZHENG Zhong 《Chinese Geographical Science》 SCIE CSCD 2024年第2期369-382,共14页
It is common to observe the epidemic risk perception(ERP)and a decline in subjective well-being(SWB)in the context of public health events,such as Corona Virus Disease 2019(COVID-19).However,there have been few studie... It is common to observe the epidemic risk perception(ERP)and a decline in subjective well-being(SWB)in the context of public health events,such as Corona Virus Disease 2019(COVID-19).However,there have been few studies exploring the impact of individuals’ERP within living space on their SWB,especially from a geographical and daily activity perspective after the resumption of work and other activities following a wave of the pandemic.In this paper,we conducted a study with 789 participants in urban China,measuring their ERP within living space and examining its influence on their SWB using path analysis.The results indicated that individuals’ERP within their living space had a significant negative effect on their SWB.The density of certain types of facilities within their living space,such as bus stops,subway stations,restaurants,fast food shops,convenience shops,hospitals,and public toilets,had a significantly negative impact on their SWB,mediated by their ERP within living space.Additionally,participation in out-of-home work and other activities not only increased individuals’ERP within living space,but also strengthened its negative effect on their SWB. 展开更多
关键词 subjective well-being epidemic risk perception living space the density of facilities out-of-home activities
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The Effects of Childhood Trauma on College Students’Depressive Symptoms:The Mediation Role of Subjective Well-Being and the Moderation Role of Resilience
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作者 Fuhua Yang Jiaci Lin +3 位作者 Rong Chen Chunlin Gao Maoying Cui Keli Yin 《International Journal of Mental Health Promotion》 2024年第9期757-766,共10页
Background:The enduring and detrimental impact of childhood trauma on later health and well-being is now well established.However,research on the relationship between childhood trauma and depressive symptoms,along wit... Background:The enduring and detrimental impact of childhood trauma on later health and well-being is now well established.However,research on the relationship between childhood trauma and depressive symptoms,along with the potential risk and protective factors,is insufficient in the context of Chinese college student population.Methods:Data on childhood trauma,depressive symptoms,resilience,and subjective well-being were collected through surveys conducted with 367 Chinese university students.The data collected in this study were analyzed using SPSS 26.0 and PROCESS 3.5.Results:The results revealed that subjective well-being mediated the relationship between childhood trauma and depressive symptoms among college students,with direct and indirect effects accounting for 59.46%and 40.54%of the total effect,respectively.The pathway process between subjective well-being and depressive symptoms was moderated by resilience,whereby an increase in resilience levels corresponded to a gradual escalation in the predictive power of subjective well-being on depressive symptoms.Conclusion:The study indicates that childhood trauma significantly and positively predicts depressive symptoms among college students,and it can also directly predict depressive symptoms through the mediating effect of subjective well-being.Elevating levels of psychological resilience and subjective well-being among college students can mitigate depression and promote psychological well-being.From the perspective of positive psychology,the present study provides a new perspective for the prevention and intervention of depressive symptoms among college students. 展开更多
关键词 Childhood trauma depressive symptoms subjective well-being RESILIENCE
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Dark Matter and Dark Energy from Lattice Model of Universe
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作者 Branislav Majerník 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第3期1045-1053,共9页
The article considers a conceptual universe model as a periodic lattice (network) with nodes defined by the wave function in a background-independent Hamiltonian based on their relations and interactions. This model g... The article considers a conceptual universe model as a periodic lattice (network) with nodes defined by the wave function in a background-independent Hamiltonian based on their relations and interactions. This model gives rise to energy bands, similar to those in semiconductor solid-state models. In this context, valence band holes are described as dark matter particles with a heavy effective mass. The conducting band, with a spontaneously symmetry-breaking energy profile, contains particles with several times lighter effective mass, which can represent luminous matter. Some possible analogies with solid-state physics, such as the comparison between dark and luminous matter, are discussed. Additionally, tiny dark energy, as intrinsic lattice Casimir energy, is calculated for a lattice with a large number of lattice nodes. 展开更多
关键词 Dark Energy Dark matter Lattice Universe Model
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Changes on Stroke Burden Attributable to Ambient Fine Particulate Matter in China
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作者 Jingyu Wang Yan Wang +5 位作者 Xiaohua Liang Keyong Huang Fangchao Liu Shufeng Chen Xiangfeng Lu Jianxin Li 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2024年第8期823-833,共11页
Objective In recent decades,China has implemented a series of policies to address air pollution.We aimed to assess the health effects of these policies on stroke burden attributable to ambient fine particulate matter(... Objective In recent decades,China has implemented a series of policies to address air pollution.We aimed to assess the health effects of these policies on stroke burden attributable to ambient fine particulate matter(PM_(2.5)).Methods Joinpoint regression was applied to explore the temporal tendency of stroke burden based on data from the Global Burden of Disease 2019 study.Results The age-standardized rates of disability-adjusted life year(DALY)for stroke attributable to ambient PM2.5 in China,increased dramatically during 1990-2012,subsequently decreased at an annual percentage change(APC)of-1.98[95% confidence interval(CI):-2.26,-1.71]during 2012-2019.For ischemic stroke(IS),the age-standardized DALY rates doubled from 1990 to 2014,and decreased at an APC of-0.83(95%CI:-1.33,-0.33)during 2014-2019.Intracerebral hemorrhage(ICH)showed a substantial increase in age-standardized DALY rates from 1990 to 2003,followed by declining trends,with APCs of-1.46(95%CI:-2.74,-0.16)during 2003-2007 and-3.33(95%CI:-3.61,-3.06)during 2011-2019,respectively.Conversely,the age-standardized DALY rates for subarachnoid hemorrhage(SAH)generally declined during 1990-2019.Conclusion Our results clarified the dynamic changes of the ambient PM_(2.5)-attributable stroke burden in China during 1990-2019,highlighting the health effects of air quality improvement policies. 展开更多
关键词 Ambient fine particulate matter STROKE Disease burden Temporal trend POLICY
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Effect of thermal maturation and organic matter content on oil shale fracturing
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作者 Fatemeh Saberi Mahboubeh Hosseini‑Barzi 《International Journal of Coal Science & Technology》 EI CAS CSCD 2024年第2期16-34,共19页
The Pabdeh Formation represents organic matter enrichment in some oil fields,which can be considered a source rock.This study is based on the Rock–Eval,Iatroscan,and electron microscopy imaging results before and aft... The Pabdeh Formation represents organic matter enrichment in some oil fields,which can be considered a source rock.This study is based on the Rock–Eval,Iatroscan,and electron microscopy imaging results before and after heating the samples.We discovered this immature shale that undergoes burial and diagenesis,in which organic matter is converted into hydro-carbons.Primary migration is the process that transports hydrocarbons in the source rock.We investigated this phenomenon by developing a model that simulates hydrocarbon generation and fluid pressure during kerogen-to-hydrocarbon conversion.Microfractures initially formed at the tip/edge of kerogen and were filled with hydrocarbons,but as catagenesis progressed,the pressure caused by the volume increase of kerogen decreased due to hydrocarbon release.The transformation of solid kerogen into low-density bitumen/oil increased the pressure,leading to the development of damage zones in the source rock.The Pabdeh Formation’s small porethroats hindered effective expulsion,causing an increase in pore fluid pressure inside the initial microfractures.The stress accumulated due to hydrocarbon production,reaching the rock’s fracture strength,further contributed to damage zone development.During the expansion process,microfractures preferentially grew in low-strength pathways such as lithology changes,laminae boundaries,and pre-existing microfractures.When the porous pressure created by each kerogen overlapped,individual microfractures interconnected,forming a network of microfractures within the source rock.This research sheds light on the complex interplay between temperature,hydrocarbon generation,and the development of expulsion fractures in the Pabdeh Formation,providing valuable insights for understanding and optimizing hydrocarbon extraction in similar geological settings. 展开更多
关键词 Oil shale MICROFRACTURE Hydrocarbon generation Organic matter Thermal maturation Primary migration
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