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Evolution of the Pearl River and its Implication for East Asian Continental Landscape Reversion 被引量:6
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作者 ZHANG Hao CUI Yuchi +2 位作者 QIAO Peijun ZHAO Meng XIANG Xuhong 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2021年第1期66-76,共11页
As the link connecting the South China Continent and the northern South China Sea(SCS),the Pearl River is the focus of sedimentology and petroleum geology research.Its evolutionary process and controlling factors are ... As the link connecting the South China Continent and the northern South China Sea(SCS),the Pearl River is the focus of sedimentology and petroleum geology research.Its evolutionary process and controlling factors are of great significance in revealing the East Asian continental landscape reorganization during the Late Cenozoic.Based on published data,’source-to-sink’provenance analyses allow systematic deliberation on the birth and evolutionary history of the Pearl River.Close to the Oligocene/Miocene boundary,an abrupt shift in the sedimentary composition indicates significant westward and northward expansion of the river’s watershed area,followed by the establishment of a near-modern fluvial network.This sedimentary change generally concurred with a series of regional geological events,including the onset of the Yangtze throughflow,large-scale development of the loess plateau,and formation of the northwestern arid zone and Asian Monsoon system.These major changes in the geology-climate-ecoenvironment system are in close response to the process of the Cenozoic Xizang(Tibetan)Plateau uplift.Consequently,the East Asian continental landscape and most of midCenozoic drainage systems underwent critical reversion into east-tilting,or east-flowing networks. 展开更多
关键词 Oligocene–Miocene landscape reversion source to sink provenance analyses East Asian continental landforms Pearl River South China
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Storage Stability in Reversion Mutation of a Rice Line Devoid of LOX-1, 2 Acquired by Ion Beam Irradiation 被引量:5
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作者 蒋家月 吴瑾华 +4 位作者 吴跃进 宋美 王相勤 刘斌美 余增亮 《Plasma Science and Technology》 SCIE EI CAS CSCD 2009年第1期116-121,共6页
The effect of absence of lipoxygenase isoenzyme (LOX) on storage stability was investigated. Rice mutant 1297 without lipoxygenase isoenzyme-1 (LOX-1) or lipoxygenase isoenzyme-2 (LOX-2) generated by ion beam ir... The effect of absence of lipoxygenase isoenzyme (LOX) on storage stability was investigated. Rice mutant 1297 without lipoxygenase isoenzyme-1 (LOX-1) or lipoxygenase isoenzyme-2 (LOX-2) generated by ion beam irradiation from Wanjian2090 and reversion mutant RM1297 with LOX-1 and LOX-2 were subjected to an accelerated-aging experiment. Shanyou63 (with LOX-1 and LOX-2 ) served as control. Results showed that the germination and dehydrogenase activity decreased while the electrical conductivity and free fatty acid content increased in all varieties with accelerated aging. In 1297 that lacked LOX-1 and 2, there were slight changes in germination, dehydrogenase activity, membrane permeability and free fatty acid content during the thirty-day accelerated-aging experiment. But in varieties with LOX-1 and LOX-2, significant changes were observed, suggesting that LOX-1, 2 might be a definite factor which influenced seed lifespan. This study also indicates that ion beam irradiation may be used as mutagen to generate mutant and reversion mutants for biological study and could become a new direction in ion beam application. 展开更多
关键词 RICE storage stability reversion mutant ion beam irradiation
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The satellite reversion of dissolved organic carbon (DOC) based on the analysis of the mixing behavior of DOC and colored dissolved organic matter: the East China Sea as an example 被引量:5
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作者 LIU Qiong PAN Delu +4 位作者 BAI Yan WU Kai CHEN Chen-Tung Arthur SUN Jun ZHANG Lin 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2013年第2期1-11,共11页
The retrieval of dissolved organic carbon (DOC) distribution by remote sensing is mainly based on the em- pirical relationship of DOC concentration and colored dissolved organic matter (CDOM) concentration in many... The retrieval of dissolved organic carbon (DOC) distribution by remote sensing is mainly based on the em- pirical relationship of DOC concentration and colored dissolved organic matter (CDOM) concentration in many literatures. To investigate the nature of this relationship, the distributions and mixing behaviors of DOC and CDOM are reviewed in the world's major estuaries and bays. It is found that, generally, the C- DOM concentration is well correlated with the salinity in most estuaries, while DOC usually shows a non- conservative behavior which leads to a weak correlation between the DOC concentration and the CDOM concentration. To establish a good satellite reversion of the DOC concentration, the East China Sea(ECS) was taken as an example, and the mixing behavior of DOC and CDOM as well as the influence of biogeo- chemical processes were analyzed except for the physical mixing process with the data from late autumn (November, 2010) and winter (December, 2009) cruises. In the two ECS cruises, the CDOM concentration was found to be tightly correlated with the salinity, influenced little by the photochemical or biological pro- cesses. The data from the winter cruise show that DOC followed a conservative mixing along the salinity gradient, while in the late autumn cruise it was significantly affected by the biological activities, resulting in a poor correlation between the DOC and the CDOM. Accordingly, an improved DOC algorithm (CSDM) was proposed: when the biological influence was significant (Chl a greater than 0.8 μg/dm3), DOC was retrieved by the conservative and biological model, and if the conservative mixing was dominant (Chl a less than 0.8 μg/dm3), the direct DOC concentration and CDOM concentration relationship was used. Based on the pro- posed algorithm, a reasonable DOC distribution for the ECS from satellite was obtained in this study, and the proposed method can be applied to the other large river-dominant marginal sea. 展开更多
关键词 dissolved organic carbon colored dissolved organic matter ESTUARY East China Sea satellite reversion
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Toward sustainable desertification reversion:A case study in Horqin Sandy Land of northern China 被引量:6
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作者 XueYong Zhao ShaoKun Wang +3 位作者 YaYong Luo WenDa Huang Hao Qu Jie Lian 《Research in Cold and Arid Regions》 CSCD 2015年第1期23-28,共6页
Desertification reversion is an interactive process involving climate, land use change, and water processes. In order to reveal the relationship between desertification reversion and these factors, we analyzed histori... Desertification reversion is an interactive process involving climate, land use change, and water processes. In order to reveal the relationship between desertification reversion and these factors, we analyzed historical data on precipitation, air temperature, desertified land changes, underground water tables, and water body changes in Naiman County in the central part of Horqin Sandy Land. Our analysis showed that during 1961-2010 the annual precipitation fluctuated dramatically and has decreased fairly consistently in recent years. The air temperature increased by 0.50-1.25℃, and the minimum temperature increased more obviously. The desertified land area increased from 42,300 km^2 in 1959 to 62,000 km^2 in 1985, and then declined to about 50,000 km^2 in 2010. The underground water tables have been lowered by about 10 m in the past 30 years, and declined more rapidly in recent years. Desertified land is significantly related to the amount of total cropland, and underground water tables are signifcantly correlated with annual precipitation and the amount of irrigated cropland. Therefore, it is necessary to pursue sustainable desertification reversion without compromising the capacity for local development and restoration of degraded land, through application of appropriate management measures for improving water availability in this region. 展开更多
关键词 sustainable desertification reversion climate change land use water table Horqin Sandy Land
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Spatial heterogeneity of soil water content in the reversion process of desertification in arid areas 被引量:3
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作者 QuanLin MA Fang CHENG +3 位作者 YouJun LIU FangLin Wang DeKuai ZHANG HuJia JIN 《Journal of Arid Land》 SCIE 2011年第4期268-277,共10页
Sandy soils in arid,rain-fed environments have low and limited water content,which is a principal factor limiting vegetation development,and a key constraint controlling the structure and functions of the ecological s... Sandy soils in arid,rain-fed environments have low and limited water content,which is a principal factor limiting vegetation development,and a key constraint controlling the structure and functions of the ecological systems in arid areas.The spatial heterogeneity of soil water content is a major soil property,and a focus of soil science and hydrology.On the southern edge of the Tengger Desert,sample plots were selected from mobile sand dunes in desertified lands that had been enclosed for 5,15 and 25 years,respectively.This study explored the dynamic and spatial heterogeneity of soil water content in these different layers of soil that were also in the reversion process of desertification.The results showed that the soil water content of the mobile sand dunes was highest when in the initial stages of the reversion process of desertification,while the soil water content in the 0-20 cm,20-40 cm and 40-60 cm layers of soil was 1.769%,3.011%,and 2.967% respectively,presenting a restoring tendency after 25 years of enclosure.There were significant differences,as a whole,in the soil water content among different restoration stages and different soil layers,respectively.Changes in soil water content,in different soil layers,at different restoration stages,exhibited exponential or spherical patterns.The spatial distribution of soil water content exhibited a mosaic patch pattern with obvious spatial heterogeneity.The ratio of the heterogeneity of spatial autocorrelation to gross spatial heterogeneity was greater than 50%.The gross spatial heterogeneity of the 0-20 cm layer of soil improved gradually,while those of the 20-40 cm and 40-60 cm layers improved initially,then weakened in the reversion process of desertification.This study revealed that restoration with sand-binding vegetation reduced soil water content,and increased its spatial heterogeneity in arid areas.However,after 25 years of vegetation-soil system restoration,the soil water content started to increase and its spatial heterogeneity started to weaken.These results will further benefit the understanding of the ecological mechanism between soil water and sand-binding vegetation. 展开更多
关键词 Tengger Desert reversion process of desertification soil water content sand-binding vegetation geostatistical analysis
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Multiphase-field simulation of austenite reversion in medium-Mn steels 被引量:2
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作者 Yan Ma Rui Zheng +4 位作者 Ziyuan Gao Ulrich Krupp Hai-wen Luo Wenwen Song olfgang Bleck 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2021年第5期847-853,共7页
Medium-Mn steels have attracted immense attention for automotive applications owing to their outstanding combination of high strength and superior ductility.This steel class is generally characterized by an ultrafine-... Medium-Mn steels have attracted immense attention for automotive applications owing to their outstanding combination of high strength and superior ductility.This steel class is generally characterized by an ultrafine-grained duplex microstructure consisting of ferrite and a large amount of austenite.Such a unique microstructure is processed by intercritical annealing,where austenite reversion occurs in a fine martensitic matrix.In the present study,austenite reversion in a medium-Mn alloy was simulated by the multiphase-field approach using the commercial software MICRESS®coupled with the thermodynamic database TCFE8 and the kinetic database MOBFE2.In particular,a faceted anisotropy model was incorporated to replicate the lamellar morphology of reversed austenite.The simulated microstructural morphology and phase transformation kinetics(indicated by the amount of phase)concurred well with experimental observations by scanning electron microscopy and in situ synchrotron high-energy X-ray diffraction,respectively. 展开更多
关键词 medium-Mn steels intercritical annealing austenite reversion phase-field simulation faceted anisotropy model
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Reversion of weak-measured quantum entanglement state 被引量:1
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作者 Shao-Jiang Du Yonggang Peng +3 位作者 Hai-Ran Feng Feng Han Lian-Wu Yang Yu-Jun Zheng 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第7期308-312,共5页
We theoretically study the reversible process of quantum entanglement state by means of weak measurement and corresponding reversible operation.We present a protocol of the reversion operation in two bodies based on t... We theoretically study the reversible process of quantum entanglement state by means of weak measurement and corresponding reversible operation.We present a protocol of the reversion operation in two bodies based on the theory of reversion of single photon and then expend it in quantum communication channels.The theoretical results demonstrate that the protocol does not break the information transmission after a weak measurement and a reversible measurement with the subsequent process in the transmission path.It can reverse the perturbed entanglement intensity evolution to its original state.Under the condition of different weak measurement intensity the protocol can reverse the perturbed quantum entanglement system perfectly.In the process we can get the classical information described by information gain from the quantum system through weak measurement operation.On the other hand,in order to realize complete reversibility,the classical information of the quantum entanglement system must obey a limited range we present in this paper in the reverse process. 展开更多
关键词 quantum entanglement weak measurement reversion operation information gain and reversibility
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Reversion Mutation in Dark Variants of Luminous Bacteria and Its Application in Gene Toxicant Monitoring 被引量:1
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作者 过建俐 孙雅量 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2002年第3期180-182,共3页
The luminous intensity of dark variant (S1) separated from photobacterium phosph oreum (A2) was 1/10 000 less than that of wild type. Ethidium bromide (EB) (0.6 mg/L), Mytomycin C (MC, 0.05 mg/L), 2 amino fluorene ... The luminous intensity of dark variant (S1) separated from photobacterium phosph oreum (A2) was 1/10 000 less than that of wild type. Ethidium bromide (EB) (0.6 mg/L), Mytomycin C (MC, 0.05 mg/L), 2 amino fluorene (2 AF, 1.0 mg/L) all cou ld strongly induce reversion mutation for S1 within 24 h and increase reversion ratio significantly. The results of experiments indicated that these revertants had stable genetic characteristic and the mutation may take place at gene levels . The mutagenesis to S1 caused by EB, MC and 2 AF was detected and it may be us ed as a new rapid, simple and sensitive method for gene toxicant monitoring. 展开更多
关键词 ethidium bromide mytomycin C 2 amino fluori ne dark variant reversion mutation gene toxicant monitoring
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Molecular mechanism of carvedilol in attenuating the reversion to fetal energy metabolism during cardiac hypertrophy development 被引量:1
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作者 胡琴 李隆贵 《Journal of Medical Colleges of PLA(China)》 CAS 2003年第5期290-294,共5页
Objective: To explore the molecular regulation mechanism of carvedilol in attenuating the reversion back towards fetal energy metabolism during the development of cardiac hypertrophy induced by coarctation of abdomina... Objective: To explore the molecular regulation mechanism of carvedilol in attenuating the reversion back towards fetal energy metabolism during the development of cardiac hypertrophy induced by coarctation of abdominal aorta (CAA) in male Wistar rats. Methods: Hemodynamic and ventricular remodeling parameters, free fatty acid content in the serum were measured in the experimental animals at 16 weeks after the surgical CAA, the rats receiving carvedilol intervention (CAR) after CAA, and those with sham operation (SH). The expressions of muscle carnitine palmitoyltransferaseⅠ (M-CPTⅠ) and medium chain acyl-CoA dehydrogenase (MCAD) mRNA in the cardiac myocytes from every group were studied with RT-PCR. Results: Significant left ventricular hypertrophy were observed in the rats 16 weeks after coarctation operation (P<0.05), together with significant free fatty acids accumulation and downregulation of M-CPTⅠ and MCAD mRNA (P<0.05) in CAA group. Carvedilol at a dose of 30 mg/kg/d for 12 weeks inhibited the left ventricular hypertrophy induced by pressure overload and enhanced the gene expressions of rate-limiting enzyme (M-CPTⅠ) and key enzyme of fatty acid (MCAD) in the CAR group compared with CAA group (P<0.05). Conclusion: Pressure overload-induced hypertrophy in CAA rats causes the reversion back towards fetal enery metabolism, that is, downregulates the expressions of rate-limiting enzyme and key enzyme of fatty acid oxidation. The intervention therapy with carvedilol, a vasodilating alpha- and beta-adrenoreceptor antagonist, attenuates the reversion of the metabolic gene expression to fetal type through upregulating M-CPTⅠ and MCAD mRNA expressions. Thus, carvedilol may exert cardioprotective effects on heart failure by the mechanism of preserving the adult metabolic gene regulation. 展开更多
关键词 CARVEDILOL pressure overload fatty acid oxidation reversion back to fetal energy metabolism
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Reversion of Bioluminescent Bacteria (Mutatox^(TM)) toTheir Luminescent State upon Exposure to OrganicCompounds, Munitions, and Metal Salts
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作者 DarrylP.ARFSTEN RichardDAVENPORT 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 1994年第2期144-149,共6页
Mutatox is a new genotoxicity bioassay which uses as the endpoint the bioluminescence produced on reversion of a dark strain of the marine bacterium Vibrio fischeri ±S9.Reversion can occur by several mechanisms, ... Mutatox is a new genotoxicity bioassay which uses as the endpoint the bioluminescence produced on reversion of a dark strain of the marine bacterium Vibrio fischeri ±S9.Reversion can occur by several mechanisms, including base substitution, frame-shift, SOS induction, and DNA intercalation. For screening, Mutatox provides many advantages over the Salmonella trphimurium (Ames) assay: it requires minimal sterility, employs a shorter incubation period, and does not require culture maintenance. Eighteen organic chemicals (phenol, polynuclear aromatic hydrocarbons, nitrotoluenes, others), Na3PO4, and 4 genotoxic metals (Cu2+, Ni2+, As3+, Cd2+) were tested. Most of the organic compounds positive in S. typhimurium assays were positive in Mutatox. None of the metals was genotoxic in V. fischeri, possibly due to poor uptake from the saline medium 展开更多
关键词 MPC DAMD Mutatox reversion of Bioluminescent Bacteria and Metal Salts toTheir Luminescent State upon Exposure to OrganicCompounds Munitions NIOSH TM
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A New Mean Reversion Model of Close-End Fund
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作者 LIU Wei 《Wuhan University Journal of Natural Sciences》 CAS 2007年第3期447-451,共5页
On the basis of fractal theory, one of the nonlinear theories, this paper studies the validity of Chinese fund market fractal time sequence through Hurst exponent, calculates the H value and proposes a new close-end f... On the basis of fractal theory, one of the nonlinear theories, this paper studies the validity of Chinese fund market fractal time sequence through Hurst exponent, calculates the H value and proposes a new close-end fund mean reversion model. Meanwhile, this paper validates the mean reversion time sequence for consecutive 54 week data of fund market. The result indicates that this model can effectively prove that Chinese close-end fund market follows the biased random walk. The research also proves that the fund discount does have mean reversion tendency and averagely the fund with high discount has a higher excess yield than that of the fund with low discount. The mean excess yield and the ratio between discount rate deviation and standard deviation demonstrate a descending relationship. The optimum investment period based on "mean reversion" is one month. Consequently this model provides a new arbitrage method through the discount of close-end fund. 展开更多
关键词 close-end fund Hurst exponent mean reversion model arbitrage opportunity
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Efficient Strip-Mode SAR Raw-Data Simulator of Extended Scenes Included Moving Targets Based on Reversion of Series
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作者 Liang Yang Daojian Zeng +1 位作者 Jianhua Yan Yaozhang Sai 《Computers, Materials & Continua》 SCIE EI 2020年第7期313-323,共11页
The Synthetic Aperture Radar(SAR)raw data generator is required to the evaluation of focusing algorithms,moving target analysis,and hardware design.The time-domain SAR simulator can generate the accurate raw data but ... The Synthetic Aperture Radar(SAR)raw data generator is required to the evaluation of focusing algorithms,moving target analysis,and hardware design.The time-domain SAR simulator can generate the accurate raw data but it needs much time.The frequency-domain simulator not only increases the efficiency but also considers the trajectory deviations of the radar.In addition,the raw signal of the extended scene included static and moving targets can be generated by some frequency-domain simulators.However,the existing simulators concentrate on the raw signal simulation of the static extended scene and moving targets at uniform speed mostly.As for the issue,the two-dimensional signal spectrum of moving targets with constant acceleration can be derived accurately based on the geometric model of a side-looking SAR and reversion of series.And a frequency-domain algorithm for SAR echo signal simulation is presented based on the two-dimensional signal spectrum.The raw data generated with proposed method is verified by several simulation experiments.In addition to reveal the efficiency of the presented frequency-domain SAR scene simulator,the computational complexity of the proposed method is compared with the time-domain approach using the complex multiplication.Numerical results demonstrate that the present method can reduce the computational time significantly without accuracy loss while simulating SAR raw data. 展开更多
关键词 Raw data simulation moving target reversion of series
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REVERSION OF MULTIDRUG RESISTANCE IN THE P-GLYCOPROTEIN POSITIVE BREAST CANCER CELL LINE(MCF-7/ADR) BY INTRODUCTION OF HAMMERHEAD RIBOZYME
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作者 袁亚维 张积仁 +2 位作者 K.J.Scanlon 陆长德 祁国荣 《Chinese Medical Sciences Journal》 CAS CSCD 1998年第1期24-28,共5页
A hammerhead ribozyme which site-specifically cleaved the GUC position in canon 880 of the mdr1 mRNA was designed. The target site was chosen between the two ATP binding sites, which may be important for the function ... A hammerhead ribozyme which site-specifically cleaved the GUC position in canon 880 of the mdr1 mRNA was designed. The target site was chosen between the two ATP binding sites, which may be important for the function of the P-Gp as an ATP-dependent pump. A DNA sequence encoding the ribozyme gene was then incorporated into a eukaryotic expression vector (pH Apr-1 neo) and transfected into the breast cancer cell line MCF-7/Adr, which is resistant to adriamycin and expresses the MDR phenotype. The ribozyme was stably expressed in the cell line by the RNA dot blotting assay. The result of Northern blot assay showed that the expressed ribozyme could decrease the level of mdrl mRNA expression by 83. 5 %; and the expressed ribozyme could inhibite the formation of p-glycoprotein detected by immuno- cy-tochemistry assay and could reduce the cell’s resistance to adrimycin; this means that the resistant cells were 1 000-fold more resistant than the parental cell line(MCF-7), whereas those cell clones that showed ribozyme expression were only 6-fold more resistant than the parental cell line. These results show that a potentially useful tool is at hand which may inactivate MDR1 mRNA and revert the multidrug resistance phenotype. 展开更多
关键词 hammerhead ribozyme multidrug resistance reversion human breast cancer cell line MCF-7/Adr
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Inhibition of mammalian target of rapamycin induces phenotypic reversion in three-dimensional cultures of malignant breast epithelial cells
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作者 Ross Booth Soonjo Kwon Eric Monson 《Journal of Biomedical Science and Engineering》 2010年第5期476-483,共8页
Inhibition of mammalian target of rapamycin (m- TOR) is a potential method for cancer treatment. Effects of rapamycin (RAP) on the reversion of malignant breast epithelial cells were investigated on three-dimensional ... Inhibition of mammalian target of rapamycin (m- TOR) is a potential method for cancer treatment. Effects of rapamycin (RAP) on the reversion of malignant breast epithelial cells were investigated on three-dimensional (3D) basement membrane extract (BME) cultures. Through continuous exposure to 20 nM of RAP, cell colony size was significantly reduced in 3D BME cultures of malignant breast epithelial cells, while normal cell colony size appeared unaffected. In unfixed 3D BME cultures of normal and RAP-treated malignant breast epithelial cells, the presence of luminal cell death was confirmed by ethidium bromide and propidium iodide labeling. Increased structural organization was observed by im- munofluorescence staining of F-actin and β-catenin in RAP-treated malignant breast epithelial cells. In monolayer cultures of normal and malignant breast epithelial cells, continuous exposure to 20 nM of RAP increased caspase 3/7 activity and decreased proliferation. Reverse transcriptase polymerase ch- ain reaction (RT-PCR) array analysis indicated a fold increase in the expression of a number of proteins related to polarity, cell-cell adhesion, and cell-matrix adhesion in the presence of RAP. Our data showed that phenotypic reversion of malignancy can be ach- ieved through RAP exposure on 3D BME cultures. This 3D BME culture system will provide correct microenvironments for observing the effects of other mTOR inhibitors on phenotypic reversion of malignant breast epithelial cells. 展开更多
关键词 RAPAMYCIN Three-Dimensional Culture BREAST Cancer reversion BASEMENT Membrane Extract mTOR Inhibitors
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Study to Solve the Problem of Color Reversion in Refined Soybean Oil
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作者 Nahed M. M. Atta Mohamed Fawzy Al-Okaby 《Food and Nutrition Sciences》 2022年第3期224-237,共14页
This study carried out on the soybean oil samples taken from the processing lines during refining process (degumming, neutralization, bleaching and deodorization process) for crude soybean oil as well as on color reve... This study carried out on the soybean oil samples taken from the processing lines during refining process (degumming, neutralization, bleaching and deodorization process) for crude soybean oil as well as on color reversed oil after deodorization step during storage for several hours to study the physical and chemical properties (color, refractive index (RI), free fatty acid (FFA), peroxide value (PV), p-Anisidine value (p-AV), total oxidative (TOTOX) value, oxidative stability (OS), saponification value (SV), iodine value (IV), unsaponifiable matter (unsap. %), soap content, minerals, waxes, total phenols content, K<sub>232</sub> and k<sub>270</sub> nm), the fatty acids composition, sterol compound, total tocopherols and their components (α, β, γ and δ tocopherol) and tocored compound for these oils and to find out the reason for the color reversion after a short period from storage for the deodorized soybean oil. Citric acid has been added (0.2%) to each color reversed and neutralized soybean oils, then procedure of bleaching and deodorization process on them, and studied its effect on the physical and chemical properties for them specially the color units (red and yellow), tocopherols contents and tocored compound. The results showed that refining process for soybean oil caused to a gradual decrease in values of AV, oxidative stability, IV, wax, % Unsapo., K<sub>232</sub> and K<sub>270</sub> nm, total polyphenols, minerals (P, Ca and Mg), total tocopherols and their compounds (α, β, γ and δ tocopherol) and also caused decrease in all sterol components, but they showed a few differences in percentages of fatty acids as result refining process. Color values (red and yellow unites) recorded gradually decreased during refining process, but these values were increased in deodorized soybean oil after storage (color reversed soybean oil). Reduction of α, β, γ and δ tocopherol contents was found to be linearly with the increase of red and yellow color units (color darking). The tocored is responsible for the color reversion phenomenon, where as maximum amount of tocored was in crude soybean oil 169.2 ppm, which gradually decreased during refining process 120.35, 99.82, 20.25, and 8.46 ppm, respectively, but it was found to be 46.5 ppm in color reversed soybean oil. Addition of citric acid (0.2%) related to the removal of tocored from soybean oil during the bleaching and deodorization process of soybean oil before and after color reversion in parallel with the significant decrease in the color values. 展开更多
关键词 Soybean Oil Color reversion Refining Process Citric Acid
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Reversion of Incommensurate Modulation in Cubic Lazurite: Example of Reversible Forced Equilibrium?
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作者 Vladimir L. Tauson Anatoly N. Sapozhnikov +1 位作者 Ekaterina V. Kaneva Sergei V. Lipko 《Natural Resources》 2014年第12期761-771,共11页
The sample of cubic lazurite, collected in the Baikal region, with incommensurately 3D modulated (ITM) structure has been studied by the method of high-temperature X-ray powder diffraction. At short time of annealing ... The sample of cubic lazurite, collected in the Baikal region, with incommensurately 3D modulated (ITM) structure has been studied by the method of high-temperature X-ray powder diffraction. At short time of annealing in high-temperature diffraction experiment the modulation recovery proceeds during cooling down the sample to room temperature. The identity of the period of both initial and recovered modulation demonstrates that the system has a structural memory. The acquired results are interpreted through comparison of thermal behavior of lazurite, sodalite and quartz structures. It is supposed that two kinetically different and thermally activated processes proceed under heating: 1) reversible framework expansion due to Si-O-Al angle increase, and 2) equalizing of periodic local distortions via the diffusion-controlled transfer of cage ions between adjacent subcells. The second process seems to be much slower than the first one, especially at lower temperatures. With increasing temperature, both processes are activated. However, the framework expands more rapidly than the cage clusters migrate, and the periodic distortions of the framework are aligned. Under lower temperatures, the framework shrinks and again accommodates to the configuration of cage cations (clusters), which may be changed at high temperature and sufficient time or may not at lower temperature, short time, unfavorable SO2 fugacity values. In the first case the modulation disappears entirely, while in the second case it arises again. The probable reason for ITM formation is the balance of counteracting energetic terms: the elastic strain energy of structure deformation and the energy of cluster ordering providing the state of forced equilibrium. The excess free energy due to structure distortion is compensated by the increment associated with the cluster ordering process. However, no significant variations in sulphur anion speciation for different degrees of modulation retention were observed by XPS S 2p. This may be due to the ordering of Na- and Ca-containing clusters rather than the clusters with different sulphur species. ITM reversion is considered as an example of reversible forced equilibrium with completely reproducible forcing factor. 展开更多
关键词 Lazurite High-Temperature X-Ray Diffraction Incommensurate Modulation reversion Mechanism FORCED EQUILIBRIUM SULPHUR SPECIATION
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Thermal Reversion of Plant Phytochromes 被引量:7
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作者 Cornelia Klose Ferenc Nagy Eberhard Schafer 《Molecular Plant》 SCIE CAS CSCD 2020年第3期386-397,共12页
Phytochromes are red/far-red reversible photoreceptors essential for plant growth and development.Phytochrome signaling is mediated by the physiologically active far-red-absorbing Pfr form that can be inactivated to t... Phytochromes are red/far-red reversible photoreceptors essential for plant growth and development.Phytochrome signaling is mediated by the physiologically active far-red-absorbing Pfr form that can be inactivated to the red-absorbing Pr ground state by light-dependent photoconversion or by light-independent thermal reversion,also termed dark reversion.Although the term“dark reversion”is justified by historical reasons and frequently used in the literature,“thermal reversion”more appropriately describes the process of light-independent but temperature-regulated Pfr relaxation that not only occurs in darkness but also in light and is used throughout the review.Thermal reversion is a critical parameter for the light sensitivity of phytochrome-mediated responses and has been studied for decades,often resulting in contradictory findings.Thermal reversion is an intrinsic property of the phytochrome molecules but can be modulated by intra-and intermolecular interactions,as well as biochemical modifications,such as phosphorylation.In this review,we outline the research history of phytochrome thermal reversion,highlighting important predictions that have been made before knowing the molecular basis.We further summarize and discuss recent findings about the molecular mechanisms regulating phytochrome thermal reversion and its functional roles in light and temperature sensing in plants. 展开更多
关键词 PHYTOCHROME PHYA PHYB thermal reversion dark reversion in vivo spectroscopy
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Telomerase-related advances in hepatocellular carcinoma:A bibliometric and visual analysis 被引量:1
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作者 Hai-Yang Li Lin-Lin Zheng +9 位作者 Nan Hu Zhi-Hao Wang Chang-Cheng Tao Ya-Ru Wang Yue Liu Zulihumaer Aizimuaji Hong-Wei Wang Rui-Qi Zheng Ting Xiao Wei-Qi Rong 《World Journal of Gastroenterology》 SCIE CAS 2024年第9期1224-1236,共13页
BACKGROUND As a critical early event in hepatocellular carcinogenesis,telomerase activation might be a promising and critical biomarker for hepatocellular carcinoma(HCC)patients,and its function in the genesis and tre... BACKGROUND As a critical early event in hepatocellular carcinogenesis,telomerase activation might be a promising and critical biomarker for hepatocellular carcinoma(HCC)patients,and its function in the genesis and treatment of HCC has gained much attention over the past two decades.AIM To perform a bibliometric analysis to systematically assess the current state of research on HCC-related telomerase.METHODS The Web of Science Core Collection and PubMed were systematically searched to retrieve publications pertaining to HCC/telomerase limited to“articles”and“reviews”published in English.A total of 873 relevant publications related to HCC and telomerase were identified.We employed the Bibliometrix package in R to extract and analyze the fundamental information of the publications,such as the trends in the publications,citation counts,most prolific or influential writers,and most popular journals;to screen for keywords occurring at high frequency;and to draw collaboration and cluster analysis charts on the basis of coauthorship and co-occurrences.VOSviewer was utilized to compile and visualize the bibliometric data.RESULTS A surge of 51 publications on HCC/telomerase research occurred in 2016,the most productive year from 1996 to 2023,accompanied by the peak citation count recorded in 2016.Up to December 2023,35226 citations were made to all publications,an average of 46.6 citations to each paper.The United States received the most citations(n=13531),followed by China(n=7427)and Japan(n=5754).In terms of national cooperation,China presented the highest centrality,its strongest bonds being to the United States and Japan.Among the 20 academic institutions with the most publications,ten came from China and the rest of Asia,though the University of Paris Cité,Public Assistance-Hospitals of Paris,and the National Institute of Health and Medical Research(INSERM)were the most prolific.As for individual contributions,Hisatomi H,Kaneko S,and Ide T were the three most prolific authors.Kaneko S ranked first by H-index,G-index,and overall publication count,while Zucman-Rossi J ranked first in citation count.The five most popular journals were the World Journal of Gastroenterology,Hepatology,Journal of Hepatology,Oncotarget,and Oncogene,while Nature Genetics,Hepatology,and Nature Reviews Disease Primers had the most citations.We extracted 2293 keywords from the publications,120 of which appeared more than ten times.The most frequent were HCC,telomerase and human telomerase reverse transcriptase(hTERT).Keywords such as mutational landscape,TERT promoter mutations,landscape,risk,and prognosis were among the most common issues in this field in the last three years and may be topics for research in the coming years.CONCLUSION Our bibliometric analysis provides a comprehensive overview of HCC/telomerase research and insights into promising upcoming research. 展开更多
关键词 TELOMERASE Bibliometric analysis Telomerase reverse transcriptase PROGNOSIS Treatment Hepatocellular carcinoma
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Danggui Shaoyao powder improves hepatic lipid metabolism in atherosclerosis mice via PPARγ-LXRα-ABCA1 pathway regulation 被引量:1
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作者 Xue Pian Yang Tang +6 位作者 Yuemeng Sun Yuhan Sheng Shuxin Yan Huimin Yuan Yan Sun Jian Cui Yuhang Li 《Journal of Traditional Chinese Medical Sciences》 CAS 2024年第2期199-206,共8页
Objective:To observe the effects of Danggui Shaoyao powder(DSP)on hepatic lipid metabolism and further explore its mechanism of action by peroxisome proliferator-activated receptor(PPARγ)-liver X receptor(LXRα)-aden... Objective:To observe the effects of Danggui Shaoyao powder(DSP)on hepatic lipid metabolism and further explore its mechanism of action by peroxisome proliferator-activated receptor(PPARγ)-liver X receptor(LXRα)-adenosine triphosphate(ATP)-binding cassette transporter A1(ABCA1)pathway regulation.Methods: Eight C57BL/6J male mice were selected as the control group,and 24 ApoE^(−/−)male mice were randomly divided into the atherosclerosis model(AS)group,atorvastatin calcium(AC)group,and DSP group(n=8 each group).To establish an AS model,ApoE^(−/−)mice were fed a high-fat diet for 16 weeks.Pathologic changes in the aortic vasculature and liver were identified using Oil Red O staining.Triglyceride(TG),cholesterol(TC),and low-density lipoprotein cholesterol(LDL-C)levels were determined in the livers using a single-reagent GPO-PAP method.Fluorescence quantitative polymerase chain reaction and western blot were used to observe and evaluate the mRNA and protein expression of the PPARγ-LXRα-ABCA1 intermediates in the liver.Results: After 16 weeks of a high-fat diet,ApoE^(−/−)mice showed more Oil Red O staining in the aorta and liver compared to the CONT group.Compared to the AS group,the DSP and AC treatment reduced aortic plaque and hepatic lipid deposition to varying degrees.Furthermore,DSP significantly reduced the hepatic lipid area in ApoE^(−/−)mice(P<.001)and decreased the levels of TG,TC,and LDL-C in liver(P<.001,P=.027,P<.001,respectively).DSP also significantly increased the levels of PPARγ,LXRα,ABCA1,and ABCG1 mRNA expression,as well as the PPARγ,LXRα,ABCA1,and ABCG1 protein expression in liver.Conclusion: DSP improved hepatic lipid metabolism via PPARγ-LXRα-ABCA1 pathway modulation for AS treatment. 展开更多
关键词 Danggui Shaoyao powder ATHEROSCLEROSIS PPARγ-LXRα-ABCA1 pathway Reverse cholesterol transport
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Enhanced tensile properties of a reversion annealed 6.5Mn-TRIP alloy via tailoring initial microstructure and cold rolling reduction 被引量:5
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作者 Minghui Cai Hongshou Huang +2 位作者 Junhua Su Hua Ding Peter D.Hodgson 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2018年第8期1428-1435,共8页
The feasibility of improving the overall performance of medium Mn steels was demonstrated via tailoring the initial microstructure and cold rolling reduction. The combined effects of cooling patterns after hot rolling... The feasibility of improving the overall performance of medium Mn steels was demonstrated via tailoring the initial microstructure and cold rolling reduction. The combined effects of cooling patterns after hot rolling (HR) and cold rolling (CR) reductions show: (1) as the cooling pattern varied from furnace cooling (FC) to oil quenching (OQ), the intercritically annealed microstructure was dramatically refined and the fraction of recrystallized ferrite dropped, regardless of CR reductions. This resulted in both high yield/ultimate tensile strengths (YS/UTS) but low total elongation to fracture (El); (2) as the CR reduction increased from 50% to 75%, the OQ-samples after annealing exhibited a more refined microstructure with relatively higher fractions of retained austenite and sub-structure, leading to higher YS and UTS but lower El; whereas the FC samples appeared to exhibit little difference in overall tensile properties in both cases. The differences in microstructural evolution with cooling patterns and CR reductions were explained by the calculated accumulated effective strain (eAES), which was considered to be related to degrees of recovery and recrystallization of the deformed martensite (α'). The optimal tensile properties of -1 GPa YS and -40 GPa.% UTSxEI were achieved in the OQ-50%CR annealed samples at 650 ℃ for 1 h. This was quite beneficial to large-scale production of ultra-high strength steels, owing to its serious springback during heaw cold working. 展开更多
关键词 Medium Mn steel reversion annealing Microstructural evolution Mechanical properties Initial microstructure Cold rolling
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