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Solar insolation driven periodicities in southwest monsoon and its impact on NE Arabian Sea paleoceanography
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作者 Syed Azharuddin Pawan Govil +2 位作者 Arun Deo Singh Ravi Mishra Mayank Shekhar 《Geoscience Frontiers》 SCIE CAS CSCD 2019年第6期2251-2263,共13页
In the northeastern(NE) Arabian Sea,the fluctuation in terrestrial and freshwater runoff directly depends on southwest monsoon(SWM) precipitation as well as the meltwater flux provided by Indus River.Therefore,analysi... In the northeastern(NE) Arabian Sea,the fluctuation in terrestrial and freshwater runoff directly depends on southwest monsoon(SWM) precipitation as well as the meltwater flux provided by Indus River.Therefore,analysis of multi-proxy spectral signatures was carried out to trace the high-resolution SWM periodicities and their influence on the productivity,regional sea level fluctuations and depositional processes in the NE Arabian Sea.The time series data of stable isotopes of oxygen(δ^18 O(G.ruber)).carbon(δ^13 C(G.ruber) and δ^13 C(org)) and nitrogen(δ^15 N).Total Organic Carbon(TOC),planktic-benthic foraminiferal ratio(P/B ratio) and>63 μm coarse fraction(CF) were used from two coastal sedimentary cores located offshore Saurashtra,NE Arabian Sea(Core SK-240/485 having 88 m water depth;Core GC/SK-240/496 having 174 m water depth).The REDFIT based spectral analysis recorded significant periodicities(>90% significance) in δ^18 0 time series centered at^1609,~667,~525,~296,~290 and^256 years.Further,the significant periodicities recorded in carbon isotopes time series(δ^13 C(G.ruber) and δ^13 C(org))centered at^681,~512,~471,~452,~438,~360,~292,~275,~269,~245 and^209 years.The significant periodicities in TOC include^471 and-322 years whereas δ^15 N time series recorded significant periodicity centered at-360 years.The significant periodicities in P/B ratio time series centered at^512,~388,~304,~250,~235,~217,~152,~139 and^135 years while CF recorded^268,~216,~209,~198,~188,~173 and^140 years significant periodicities.The observed periodicities in the multi-proxy record consist of similar cycles(within the radiocarbon dating error) which also natch with previously reported solar insolation influenced SWM and other global and regional cycles.Further,the stationarity of the data has been verified using wavelet analysis and shows similar periodicities as observed in REDFIT analysis.Thereafter,the depositional behaviour was studied using correlation analysis of the common periods of δ^18 0 time series of both the cores.The result suggests that the depositional behaviour was different for both the core sites during the early Holocene and became similar during the middle Holocene.The correlation analysis of Total Solar Index(TSI) with δ^18 O time series reveals a significant correlation with the core SK-240/485 whereas an insignificant correlation with the core GC/SK-240/496.These observations suggest that the solar insolation has been a leading factor responsible for the SWM trends during the Holocene which may have further influenced the productivity.regional sea level fluctuations and depositional conditions in the NE Arabian Sea.However,these trends are better preserved in shallow marine sediments as compared to the deeper marine sediments. 展开更多
关键词 SOUTHWEST MONSOON periodicities Arabian SEA Spectral analysis FORAMINIFERA
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Climatic periodicities recorded in lake sediment magnetic susceptibility data:Further evidence for solar forcing on Indian summer monsoon 被引量:3
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作者 Anish Kumar Warrier Kizhur Sandeep Rajasekharaiah Shankar 《Geoscience Frontiers》 SCIE CAS CSCD 2017年第6期1349-1355,共7页
The Indian summer monsoon exhibits considerable spatio-temporal variability.It is therefore important to understand its dynamics and the inherent periodicities.In this study,we have performed spectral and wavelet anal... The Indian summer monsoon exhibits considerable spatio-temporal variability.It is therefore important to understand its dynamics and the inherent periodicities.In this study,we have performed spectral and wavelet analyses of magnetic susceptibility data for sediments from Thimmannanayakanakere(TK)-a small lake in southern India.The main objective of this investigation is to identify and explain the possible origin of the prominent periodicities present in the magnetic susceptibility data.Significant periodicities in the TK χ_(lf)data are centered at 906,232,147,128,96,61,54 and 44 years,which might have a solar origin.The wavelet power spectrum of the raw and detrended χ_(lf)data confirms the findings of spectral analysis and also provides temporal variations of the significant cyclicities during the past3700 cal.years B.P.Positive correlation is documented between sunspot activity and TK xif data;crossspectral analysis of the reconstructed sunspot data and TK xif data suggest that there is a strong coherence between the two datasets as significant periodicities are documented in both.There is a good match between the TK xif and the reconstructed total solar irradiance data for the past 1200 years.However,an out-of-phase relationship is documented at certain time-intervals,which may be attributed to uncertainties in the age-depth model.The results obtained from this study show that solar variations are the main controlling factor of the southwest monsoon and,like other archives from different regions in India,the TK lake sediments have also recorded these solar signatures. 展开更多
关键词 Spectral analysis PERIODICITY Paleorainfall Lake SEDIMENTS Magnetic susceptibility SOUTHERN India
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Periodicities in the emplacement of large igneous provinces through the Phanerozoic:Relations to ocean chemistry and marine biodiversity evolution 被引量:8
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作者 Andreas Prokoph Hafida E1 Bilali Richard Ernst 《Geoscience Frontiers》 SCIE CAS CSCD 2013年第3期263-276,共14页
Large igneous provinces (LIPs) are considered a relevant cause for mass extinctions of marine life throughout Earth's history. Their flood basalts and associated intrusions can cause significant release of SO4 and ... Large igneous provinces (LIPs) are considered a relevant cause for mass extinctions of marine life throughout Earth's history. Their flood basalts and associated intrusions can cause significant release of SO4 and CO2 and consequently, cause major environmental disruptions. Here, we reconstruct the long-term periodic pattern of LIP emplacement and its impact on ocean chemistry and biodiversity from δ34Ssulfate of the last 520 Ma under particular consideration of the preservation limits of LIP records. A combination of cross-wavelet and other time-series analysis methods has been applied to quantify a potential chain of linkage between LIP emplacement periodicity, geochemical changes and the Phanerozoic marine genera record. We suggest a mantle plume cyclicity represented by LIP volumes (V) of V= (350-770) × 103km3sin(27πt/ 170 Ma)+ (300-650)× 103 km3 sin(2πt/64.5 Ma + 2.3) for t= time in Ma. A shift from the 64.5 Ma to a weaker -28-35 Ma LIP cyclicity during the Jurassic contributes together with probably independent changes in the marine sulfur cycle to less ocean anoxia, and a general stabilization of ocean chemistry and increasing marine biodiversity throughout the last -135 Ma. The LIP cycle pattern is coherent with marine biodiversity fluctuations corresponding to a reduction of marine biodiversity of -120 genera/Ma at 600 x 103 km3 LIP eruption volume. The 62-65 Ma LIP cycle pattern as well as excursion in -34Ssulfate and marine genera reduction suggest a not-vet identified found LIP event at - 440-450 Ma. 展开更多
关键词 Large igneous provinces Wavelet transform Sulfur isotope Mantle plume Marine biodiversity Periodicity
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Seasonality Variability and Periodicities for Ultra-Deep Earthquakes Worldwide
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作者 Marilia Hagen Anibal Azevedo 《Open Journal of Earthquake Research》 2019年第1期1-18,共18页
Our last study found that deepest-depth earthquakes with larger magnitudes (M6 or above) showed seasonality, which is dependent on the area searched. The main results indicated strong evidence that the causes for the ... Our last study found that deepest-depth earthquakes with larger magnitudes (M6 or above) showed seasonality, which is dependent on the area searched. The main results indicated strong evidence that the causes for the delays in enhancements along the period investigated were due to the tectonics also, not only the season. Therefore, if the inquiry was about an area in Northern Hemisphere, the season in which the increases occurred is different than the season in the Southern Hemisphere. Also, higher latitudes in the Northern Hemisphere or around the Equator, displayed seasonality similarly where the tremors appear to increase during the Spring and Summer. This did not happen to the Southern Hemisphere where disturbances and anomalies occurred without showing much connection to the seasons in the analyzed period. However, some of the regions presented periodicities independent from the seasons. 展开更多
关键词 SEASONS SUBDUCTION Zones Earthquakes PERIODICITY South HEMISPHERE
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Computational Method for Extracting and Modeling Periodicities in Time Series
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作者 Eduardo González-Rodríguez Héctor Villalobos +1 位作者 Víctor Manuel Gomez-Munoz Alejandro Ramos-Rodríguez 《Open Journal of Statistics》 2015年第6期604-617,共14页
Periodicity is common in natural processes, however, extraction tools are typically difficult and cumbersome to use. Here we report a computational method developed in MATLAB through a function called Periods with the... Periodicity is common in natural processes, however, extraction tools are typically difficult and cumbersome to use. Here we report a computational method developed in MATLAB through a function called Periods with the aim to find the main harmonic components of time series data. This function is designed to obtain the period, amplitude and lag phase of the main harmonic components in a time series (Periods and lag phase components can be related to climate, social or economic events). It is based on methods of periodic regression with cyclic descent and includes statistical significance testing. The proposed method is very easy to use. Furthermore, it does not require full understanding of time series theory, nor require many inputs from the user. However, it is sufficiently flexible to undertake more complex tasks such as forecasting. Additionally, based on previous knowledge, specific periods can be included or excluded easily. The output results are organized into two groups. One contains the parameters of the adjusted model and their F statistics. The other consists of the harmonic parameters that best fit the original series according to their importance and the summarized statistics of the comparisons between successive models in the cyclic descent process. Periods is tested with both, simulated and actual sunspot and Multivariate ENSO Index data to show its performance and accuracy. 展开更多
关键词 Time Series Cyclic Descent Harmonic PERIODICITY Forecasting SUNSPOT Multivariate ENSO Index
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The Detection of Hidden Periodicities in EEG
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作者 YOU Rong-yi 《Chinese Journal of Biomedical Engineering(English Edition)》 2007年第4期179-183,共5页
A novel method for detecting the hidden periodicities in EEG is proposed. By using a width-varying window in the time domain, the structure function of EEG time series is defined. It is found that the minima of the st... A novel method for detecting the hidden periodicities in EEG is proposed. By using a width-varying window in the time domain, the structure function of EEG time series is defined. It is found that the minima of the structure function, within a finite window width, can be found regularly, which indicate that there are some certain periodicities associated with EEG time series. Based on the structure function, a further quadratic structure function of EEG time series is defined. By quadratic structure function, it can be seen that the periodicities of EEG become more obvious, moreover, the period of EEG can be determined accurately. These results will be meaningful for studying the neuron activity inside the human brain. 展开更多
关键词 electroencephalogram (EEG) PERIODICITY structure function
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The neutrophil–osteogenic cell axis promotes bone destruction in periodontitis 被引量:1
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作者 Yutaro Ando Masayuki Tsukasaki +12 位作者 Nam Cong-Nhat Huynh Shizao Zang Minglu Yan Ryunosuke Muro Kazutaka Nakamura Masatsugu Komagamine Noriko Komatsu Kazuo Okamoto Kenta Nakano Tadashi Okamura Akira Yamaguchi Kazuyuki Ishihara Hiroshi Takayanagi 《International Journal of Oral Science》 SCIE CAS CSCD 2024年第1期154-162,共9页
The immune-stromal cell interactions play a key role in health and diseases. In periodontitis, the most prevalent infectious disease in humans, immune cells accumulate in the oral mucosa and promote bone destruction b... The immune-stromal cell interactions play a key role in health and diseases. In periodontitis, the most prevalent infectious disease in humans, immune cells accumulate in the oral mucosa and promote bone destruction by inducing receptor activator of nuclear factor-κB ligand (RANKL) expression in osteogenic cells such as osteoblasts and periodontal ligament cells. However, the detailed mechanism underlying immune–bone cell interactions in periodontitis is not fully understood. Here, we performed single-cell RNAsequencing analysis on mouse periodontal lesions and showed that neutrophil–osteogenic cell crosstalk is involved in periodontitis-induced bone loss. The periodontal lesions displayed marked infiltration of neutrophils, and in silico analyses suggested that the neutrophils interacted with osteogenic cells through cytokine production. Among the cytokines expressed in the periodontal neutrophils, oncostatin M (OSM) potently induced RANKL expression in the primary osteoblasts, and deletion of the OSM receptor in osteogenic cells significantly ameliorated periodontitis-induced bone loss. Epigenomic data analyses identified the OSM-regulated RANKL enhancer region in osteogenic cells, and mice lacking this enhancer showed decreased periodontal bone loss while maintaining physiological bone metabolism. These findings shed light on the role of neutrophils in bone regulation during bacterial infection, highlighting the novel mechanism underlying osteoimmune crosstalk. 展开更多
关键词 period NEUTROPHIL DESTRUCTION
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Preweaning period is a critical window for rumen microbial regulation of average daily gain in Holstein heifer calves 被引量:1
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作者 Shengyang Xu Chong Jiao +1 位作者 Qiyu Diao Yan Tu 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第1期396-411,共16页
Background Rumen bacterial groups can affect growth performance,such as average daily gain(ADG),feed intake,and efficiency.The study aimed to investigate the inter-relationship of rumen bacterial composition,rumen fer... Background Rumen bacterial groups can affect growth performance,such as average daily gain(ADG),feed intake,and efficiency.The study aimed to investigate the inter-relationship of rumen bacterial composition,rumen fermentation indicators,serum indicators,and growth performance of Holstein heifer calves with different ADG.Twelve calves were chosen from a trail with 60 calves and divided into higher ADG(HADG,high pre-and post-weaning ADG,n=6)and lower ADG(LADG,low pre-and post-weaning ADG,n=6)groups to investigate differences in bacterial composition and functions and host phenotype.Results During the preweaning period,the relative abundances of propionate producers,including g_norank_f_Butyricicoccaceae,g_Pyramidobacter,and g_norank_f_norank_o_Clostridia_vadin BB60_group,were higher in HADG calves(LDA>2,P<0.05).Enrichment of these bacteria resulted in increased levels of propionate,a gluconeogenic precursor,in preweaning HADG calves(adjusted P<0.05),which consequently raised serum glucose concentrations(adjusted P<0.05).In contrast,the relative abundances of rumen bacteria in post-weaning HADG calves did not exert this effect.Moreover,no significant differences were observed in rumen fermentation parameters and serum indices between the two groups.Conclusions The findings of this study revealed that the preweaning period is the window of opportunity for rumen bacteria to regulate the ADG of calves. 展开更多
关键词 Average daily gain CALVES Preweaning period Rumen microbiota
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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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Perioperative cardiac risks in myasthenia gravis 被引量:1
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作者 Deb Sanjay Nag Abhishek Chatterjee +2 位作者 Pratap Rudra Mahanty Merina Sam Murari Kumar Bharadwaj 《World Journal of Clinical Cases》 SCIE 2024年第13期2147-2150,共4页
Myasthenia gravis(MG)is an autoimmune disorder that affects the neuromuscular junction.The primary pathology in MG involves the presence of autoantibodies to acetylcholine receptors(AChRs),which results in qualitative... Myasthenia gravis(MG)is an autoimmune disorder that affects the neuromuscular junction.The primary pathology in MG involves the presence of autoantibodies to acetylcholine receptors(AChRs),which results in qualitative and quantitative reductions in the availability of functional AChRs.Cardiac muscles are also affected,resulting in various perioperative cardiac complications.Antistriational antibodies are commonly reported in MG cases with cardiac involvement.In the presence of thymoma,the prevalence of cardiac manifestations in patients with MG increases to approximately 10%-15%.Cardiac involvement in MG may range from asymptomatic electrocardiogram changes to ventricular tachycardia,myocarditis,conduction disorders,heart failure,and sudden death.Increased incidence of atrial fibrillation,ventricular and supraventricular extra systoles,and prolonged QTc have also been reported in patients with MG.Clinicians should consider the evaluation of autonomic dysfunction and risk of cardiovascular disease in patients with MG. 展开更多
关键词 Myasthenia Gravis Perioperative period RECEPTORS CHOLINERGIC ANESTHESIA
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ON THE STABILITY OF PERIODIC SOLUTIONS OF PIECEWISE SMOOTH PERIODIC DIFFERENTIAL EQUATIONS
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作者 Maoan HAN Yan YE 《Acta Mathematica Scientia》 SCIE CSCD 2024年第4期1524-1535,共12页
In this paper,we address the stability of periodic solutions of piecewise smooth periodic differential equations.By studying the Poincarémap,we give a sufficient condition to judge the stability of a periodic sol... In this paper,we address the stability of periodic solutions of piecewise smooth periodic differential equations.By studying the Poincarémap,we give a sufficient condition to judge the stability of a periodic solution.We also present examples of some applications. 展开更多
关键词 periodic solution Poincarémap periodic equation stability
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Tim4 deficiency reduces CD301b+macrophage and aggravates periodontitis bone loss
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作者 Ziming Wang Hao Zeng +11 位作者 Can Wang Jiaolong Wang Jing Zhang Shuyuan Qu Yue Han Liu Yang Yueqi Ni Wenan Peng Huan Liu Hua Tang Qin Zhao Yufeng Zhang 《International Journal of Oral Science》 SCIE CAS CSCD 2024年第2期280-292,共13页
Periodontitis is a common chronic inflammatory disease that causes the periodontal bone destruction and may ultimately result in tooth loss.With the progression of periodontitis,the osteoimmunology microenvironment in... Periodontitis is a common chronic inflammatory disease that causes the periodontal bone destruction and may ultimately result in tooth loss.With the progression of periodontitis,the osteoimmunology microenvironment in periodontitis is damaged and leads to the formation of pathological alveolar bone resorption.CD301b^(+)macrophages are specific to the osteoimmunology microenvironment,and are emerging as vital booster for conducting bone regeneration.However,the key upstream targets of CD301b^(+)macrophages and their potential mechanism in periodontitis remain elusive.In this study,we concentrated on the role of Tim4,a latent upstream regulator of CD301b^(+)macrophages.We first demonstrated that the transcription level of Timd4(gene name of Tim4)in CD301b^(+)macrophages was significantly upregulated compared to CD301b^(-) macrophages via high-throughput RNA sequencing.Moreover,several Tim4-related functions such as apoptotic cell clearance,phagocytosis and engulfment were positively regulated by CD301b^(+)macrophages.The single-cell RNA sequencing analysis subsequently discovered that Cd301b and Timd4 were specifically co-expressed in macrophages.The following flow cytometric analysis indicated that Tim4 positive expression rates in total macrophages shared highly synchronized dynamic changes with the proportions of CD301b^(+)macrophages as periodontitis progressed.Furthermore,the deficiency of Tim4 in mice decreased CD301b^(+)macrophages and eventually magnified alveolar bone resorption in periodontitis.Additionally,Tim4 controlled the p38 MAPK signaling pathway to ultimately mediate CD301b^(+)macrophages phenotype.In a word,Tim4 might regulate CD301b^(+)macrophages through p38 MAPK signaling pathway in periodontitis,which provided new insights into periodontitis immunoregulation as well as help to develop innovative therapeutic targets and treatment strategies for periodontitis. 展开更多
关键词 PERIOD UPSTREAM eventually
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A molecular insight into coke formation process of vacuum residue in thermal cracking reaction
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作者 Ji-Guang Li Xin Guo Huan-Di Hou 《Petroleum Science》 SCIE EI CAS CSCD 2024年第3期2130-2138,共9页
Understanding the coking behaviors has been considered to be really essential for developing better vacuum residue processing technologies.A battery of thermal cracking tests of typical vacuum residue at 410℃ with va... Understanding the coking behaviors has been considered to be really essential for developing better vacuum residue processing technologies.A battery of thermal cracking tests of typical vacuum residue at 410℃ with various reaction time were performed to evaluate the coke formation process.The total yields of ideal components including naphtha,atmospheric gas oil(AGO)and vacuum gas oil(VGO)of thermal cracking reactions increased from 10.89%to 40.81%,and the conversion ratios increased from8.05%to 43.33%with increasing the reaction time from 10 to 70 min.The asphaltene content increased from 12.14%to a maximum of 22.39%and then decreased,and this maximum of asphaltene content occurred at the end of the coking induction period.The asphaltenes during the coking induction period,at the end and after coking induction period of those tested thermal cracking reactions were characterized to disclose the structure changing rules for coke formation process,and the coke formation pathways were discussed to reveal the coke formation process at molecular level. 展开更多
关键词 Vacuum residue Thermal cracking ASPHALTENE Coking induction period SULFUR NITROGEN
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Tuning Second Chern Number in a Four-Dimensional Topological Insulator by High-Frequency Time-Periodic Driving
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作者 刘峥嵘 陈锐 周斌 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第4期77-89,共13页
Floquet engineering has attracted considerable attention as a promising approach for tuning topological phase transitions.We investigate the effects of high-frequency time-periodic driving in a four-dimensional(4D)top... Floquet engineering has attracted considerable attention as a promising approach for tuning topological phase transitions.We investigate the effects of high-frequency time-periodic driving in a four-dimensional(4D)topological insulator,focusing on topological phase transitions at the off-resonant quasienergy gap.The 4D topological insulator hosts gapless three-dimensional boundary states,characterized by the second Chern number C_(2).We demonstrate that the second Chern number of 4D topological insulators can be modulated by tuning the amplitude of time-periodic driving.This includes transitions from a topological phase with C_(2)=±3 to another topological phase with C_(2)=±1,or to a topological phase with an even second Chern number C_(2)=±2,which is absent in the 4D static system.Finally,the approximation theory in the high-frequency limit further confirms the numerical conclusions. 展开更多
关键词 TOPOLOGICAL TRANSITIONS PERIODIC
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Further study on the genesis of lamellar calcite veins in lacustrine black shale--A case study of Paleogene in Dongying Depression, China
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作者 Guan-Min Wang Yun-Jiao Zhang +3 位作者 Zi-Yuan Yin Rui Zhu Zhi-Yao Hou Yu Bai 《Petroleum Science》 SCIE EI CAS CSCD 2024年第3期1508-1523,共16页
Lamellar calcite veins are prevalent in carbonate-rich,lacustrine dark shale.The formation mechanisms of these veins have been extensively debated,focusing on factors such as timing,depth,material source,and driving f... Lamellar calcite veins are prevalent in carbonate-rich,lacustrine dark shale.The formation mechanisms of these veins have been extensively debated,focusing on factors such as timing,depth,material source,and driving forces.This paper examines dark lacustrine shale lamellar calcite veins in the Paleogene strata of Dongying Depression,using various analytical techniques:petrography,isotope geochemistry,cathodoluminescence,inclusion thermometry,and electron probe micro-analysis.Two distinct types of calcite veins have been identified:granular calcite veins and sparry calcite veins.These two types differ significantly in color,grain structure,morphology,and inclusions.Through further investigation,it was observed that vein generation occurred from the shallow burial period to the maturation of organic matter,with a transition from granular calcite veins to sparry calcite veins.The granular calcite veins exhibit characteristics associated with the shallow burial period,including plastically deformed laminae and veins,the development of strawberry pyrite,the absence of oil and gas,weak fractionation in oxygen isotopes,and their contact relationship with sparry calcite veins.These granular calcite veins were likely influenced by the reduction of sulfate bacteria.On the other hand,sparry calcite veins with fibrous grains are antitaxial and closely linked to the evolution and maturation of organic matter.They contain oil and gas inclusions and show a distribution range of homogenization temperature between 90℃ and 120℃ and strong fractionation in oxygen isotopes,indicating formation during the hydrocarbon expulsion period.The carbon isotope analysis of the surrounding rocks and veins suggests that the material for vein formation originates from the shale itself,specifically authigenic micritic calcite modified by the action of methanogens.The opening of horizontal fractures and vein formation is likely driven by fluid overpressure resulting from undercompaction and hydrocarbon expulsion.Veins may form rapidly or through multi-stage composite processes.Early veins are predominantly formed in situ,while late veins are a result of continuous fluid migration and convergence.Furthermore,the veins continue to undergo modification even after formation.This study emphasizes that the formation of lamellar calcite veins in shale is a complex diagenetic process influenced by multiple factors:biology,organic matter,and inorganic processes,all operating at various stages throughout the shale's diagenetic history. 展开更多
关键词 Calcite veins Shale diagenesis Material source Formation period Formation mechanism
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Repeated inoculation with rumen fluid accelerates the rumen bacterial transition with no benefit on production performance in postpartum Holstein dairy cows
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作者 Fanlin Kong Feiran Wang +3 位作者 Yijia Zhang Shuo Wang Wei Wang Shengli Li 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第2期795-811,共17页
Background The dairy cow’s postpartum period is characterized by dramatic physiological changes,therefore imposing severe challenges on the animal for maintaining health and milk output.The dynamics of the ruminal mi... Background The dairy cow’s postpartum period is characterized by dramatic physiological changes,therefore imposing severe challenges on the animal for maintaining health and milk output.The dynamics of the ruminal microbiota are also tremendous and may play a crucial role in lactation launch.We aim to investigate the potential benefits of early microbial intervention by fresh rumen microbiota transplantation(RMT)and sterile RMT in postpartum dairy cows.Twelve fistulated peak-lactation dairy cows were selected to be the donors for rumen fluid collection.Thirty postpartum cows were divided into 3 groups as the transplantation receptors respectively receiving 10 L fresh rumen fluid(FR),10 L sterile rumen fluid(SR),or 10 L saline(CON)during 3 d after calving.Results Production performance,plasma indices,plasma lipidome,ruminal microbiome,and liver transcriptome were recorded.After fresh and sterile RMT,we found that the molar proportion of propionic acid was increased on d 7 in the FR and SR groups and the bacterial composition was also significantly changed when compared with the CON group.A similarity analysis showed that the similarities between the CON group and FR or SR group on d 7 were 48.40%or 47.85%,whereas the similarities between microbiota on d 7 and 21 in the FR and SR groups were 68.34%or 66.85%.Dry matter intake and feed efficiency were not affected by treatments.Plasmaβ-hydroxybutyrate concentration in the FR group was decreased and significantly different lipids mainly included phosphatidylcholine and lysophosphatidylcholine containing polyunsaturated fatty acids.Hepatic transcriptomics analysis indicated acutephase response pathways were upregulated in the SR group.Conclusions Our study suggests that RMT can shorten the transition process of the ruminal microbiota of postpartum dairy cows with no benefit on dry matter intake or feed efficiency.Inoculation with rumen fluid may not be a useful approach to promote the recovery of postpartum dairy cows. 展开更多
关键词 Dairy cow LIPIDOMICS Liver Rumen microbiota transplantation Transition period
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Sinensetin protects against periodontitis through binding to Bach1 enhancing its ubiquitination degradation and improving oxidative stress
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作者 Zhiyao Yuan Junjie Li +6 位作者 Fuyu Xiao Yu Wu Zhiting Zhang Jiahong Shi Jun Qian Xudong Wu Fuhua Yan 《International Journal of Oral Science》 SCIE CAS CSCD 2024年第3期553-562,共10页
Periodontitis is a chronic inflammatory and immune reactive disease induced by the subgingival biofilm.The therapeutic effect for susceptible patients is often unsatisfactory due to excessive inflammatory response and... Periodontitis is a chronic inflammatory and immune reactive disease induced by the subgingival biofilm.The therapeutic effect for susceptible patients is often unsatisfactory due to excessive inflammatory response and oxidative stress.Sinensetin(Sin)is a nature polymethoxylated flavonoid with anti-inflammatory and antioxidant activities.Our study aimed to explore the beneficial effect of Sin on periodontitis and the specific molecular mechanisms.We found that Sin attenuated oxidative stress and inflammatory levels of periodontal ligament cells(PDLCs)under inflammatory conditions.Administered Sin to rats with ligation-induced periodontitis models exhibited a protective effect against periodontitis in vivo.By molecular docking,we identified Bach1 as a strong binding target of Sin,and this binding was further verified by cellular thermal displacement assay and immunofluorescence assays.Chromatin immunoprecipitation-quantitative polymerase chain reaction results also revealed that Sin obstructed the binding of Bach1 to the HMOX1 promoter,subsequently upregulating the expression of the key antioxidant factor HO-1.Further functional experiments with Bach1 knocked down and overexpressed verified Bach1 as a key target for Sin to exert its antioxidant effects.Additionally,we demonstrated that Sin prompted the reduction of Bach1 by potentiating the ubiquitination degradation of Bach1,thereby inducing HO-1 expression and inhibiting oxidative stress.Overall,Sin could be a promising drug candidate for the treatment of periodontitis by targeting binding to Bach1. 展开更多
关键词 Bach1 period PROMPT
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Structural color of metallic glass through picosecond laser
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作者 Yue’e Zhang Xing Tong +3 位作者 Yuqiang Yan Shuo Cao Hai-Bo Ke Wei-Hua Wang 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第10期120-128,共9页
The alteration in surface color of metallic glasses(MGs)holds great significance in the context of microstructuredesign and commercial utility.It is essential to accurately describe the structures that are formed duri... The alteration in surface color of metallic glasses(MGs)holds great significance in the context of microstructuredesign and commercial utility.It is essential to accurately describe the structures that are formed during the laser and colorseparation processes in order to develop practical laser coloring applications.Due to the high oxidation sensitivity of Labasedmetallic glass,it can broaden the color range but make it more complex.Structure coloring by laser processing on thesurface of La-based metallic glass can be conducted after thermoplastic forming.It is particularly important to clarify therole of structure and composition in the surface coloring process.The aim is to study the relationship between amorphoussurface structural color,surface geometry,and oxide formation by laser processing in metallic glasses.The findings revealedthat the periodic structure primarily determines the surface color at laser energy densities below 1.0 J/mm^(2).In contrast,thesurface color predominantly depends on the proportion of oxides that are formed when energy densities exceed 1.0 J/mm^(2).Consequently,this study provides a novel concept for the fundamental investigation of laser coloring and establishes a newavenue for practical application. 展开更多
关键词 metallic glass picosecond laser periodic structure OXIDES
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Solitons and Their Biperiodic Pulsation in Ultrafast Fiber Lasers Based on CB/GO
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作者 Zhen-Tao Ju Zhi-Zeng Si +1 位作者 Xin Yan Chao-Qing Dai 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第8期28-32,共5页
The carbon black(CB)is introduced to manufacture CB/graphene oxide(GO)composite material to mitigate limitations of GO as a saturable absorber with the excellent performance in ultrafast fiber lasers.At a central wave... The carbon black(CB)is introduced to manufacture CB/graphene oxide(GO)composite material to mitigate limitations of GO as a saturable absorber with the excellent performance in ultrafast fiber lasers.At a central wavelength of 1555.5 nm,the stable mode-locked pulse with width of 656 fs,repetition rate of 20.16 MHz,and high signal-to-noise ratio of 82.07 dB is experimentally obtained.Additionally,experimental observations for pulsation phenomena of vector biperiodic solitons combining period-1 and period-17,period-2 and period-32,period-3 and period-36 are verified via simulations. 展开更多
关键词 fiber periodic ABSORBER
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Periodic signal extraction of GNSS height time series based on adaptive singular spectrum analysis
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作者 Chenfeng Li Peibing Yang +1 位作者 Tengxu Zhang Jiachun Guo 《Geodesy and Geodynamics》 EI CSCD 2024年第1期50-60,共11页
Singular spectrum analysis is widely used in geodetic time series analysis.However,when extracting time-varying periodic signals from a large number of Global Navigation Satellite System(GNSS)time series,the selection... Singular spectrum analysis is widely used in geodetic time series analysis.However,when extracting time-varying periodic signals from a large number of Global Navigation Satellite System(GNSS)time series,the selection of appropriate embedding window size and principal components makes this method cumbersome and inefficient.To improve the efficiency and accuracy of singular spectrum analysis,this paper proposes an adaptive singular spectrum analysis method by combining spectrum analysis with a new trace matrix.The running time and correlation analysis indicate that the proposed method can adaptively set the embedding window size to extract the time-varying periodic signals from GNSS time series,and the extraction efficiency of a single time series is six times that of singular spectrum analysis.The method is also accurate and more suitable for time-varying periodic signal analysis of global GNSS sites. 展开更多
关键词 GNSS Time series Singular spectrum analysis Trace matrix Periodic signal
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