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Eruptive xanthomas in a patient with severe hypertriglyceridemia:A case report
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作者 Ci Ren Ling Zhu +3 位作者 Yan-Chao Niu Lian-Yu Tu Zhou-Feng Jin Jian Zhang 《World Journal of Clinical Cases》 SCIE 2024年第16期2842-2846,共5页
BACKGROUND Xanthomatosis,a metabolic disorder causing yellow growths(xanthomas),poses challenges in lipid metabolism.This case study introduces the first documented instance within China's Yi population,emphasizin... BACKGROUND Xanthomatosis,a metabolic disorder causing yellow growths(xanthomas),poses challenges in lipid metabolism.This case study introduces the first documented instance within China's Yi population,emphasizing the need to explore dietary habits and treatment strategies tailored to this specific community.CASE SUMMARY Xanthomatosis is a metabolic disorder where lipid metabolism goes awry,resulting in the development of yellowish growths called xanthomas.A male patient,47 years of age,from China's Yi population,who is obese,visited our dermatology clinic complaining of widespread,non-painful rashes that have been present for two weeks.The patient works as a chef and has a diet that frequently includes oily and greasy foods.This case represents the initial documentation of xanthomatosis within the Yi population in China,offering a theoretical foundation for understanding dietary patterns and treatment options specific to the Yi community.CONCLUSION The first report of xanthomatosis in the Yi population in China lays a theoretical foundation for understanding Yi dietary patterns and treatment. 展开更多
关键词 eruptive xanthomas HYPERTRIGLYCERIDEMIA Yi ethnicity DERMATOLOGY Chef Case report
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Subaqueous volcanic eruptive facies,facies model and its reservoir significance in a continental lacustrine basin:A case from the Cretaceous in Chaganhua area of southern Songliao Basin,NE China 被引量:1
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作者 SHAN Xuanlong MU Hansheng +5 位作者 LIU Yuhu LI Ruilei ZHU Jianfeng SHI Yunqian LENG Qinglei YI Jian 《Petroleum Exploration and Development》 SCIE 2023年第4期826-839,共14页
The conventional lithofacies and facies model of subaerial and marine pyroclastic rocks cannot reflect the characteristics of subaqueous volcanic edifice in lacustrine basins.In order to solve this problem,the lithofa... The conventional lithofacies and facies model of subaerial and marine pyroclastic rocks cannot reflect the characteristics of subaqueous volcanic edifice in lacustrine basins.In order to solve this problem,the lithofacies of subaqueous eruptive pyroclastic rocks is discussed and the facies model is established by taking the tuff cone of Cretaceous Huoshiling Formation in the Chaganhua area of the Changling fault depression,Songliao Basin as the research object.The results indicate that the subaqueous eruptive pyroclastic rocks in the Songliao Basin can be divided into two facies and four subfacies.The two facies are the subaqueous explosive facies and the volcanic sedimentary facies that is formed during the eruption interval.The subaqueous explosive facies can be further divided into three subfacies:gas-supported hot pyroclastic flow subfacies,water-laid density current subfacies and subaqueous fallout subfacies.The volcanic sedimentary facies consists of pyroclastic sedimentary rocks containing terrigenous clast subfacies.A typical facies model of the tuff cone that is formed by subaqueous eruptions in the Songliao Basin was established.The tuff cone is generally composed of multiple subaqueous eruption depositional units and can be divided into two facies associations:near-source facies association and far-source facies association.The complete vertical succession of one depositional unit of the near-source facies association is composed of pyroclastic sedimentary rocks containing terrigenous clast subfacies,gas-supported hot pyroclastic flow subfacies,water-laid density current subfacies and subaqueous fallout subfacies from bottom to top.The depositional unit of the far-source facies association is dominated by the subaqueous fallout subfacies and contains several thin interlayered deposits of the water-laid density current subfacies.The gas-supported hot pyroclastic flow subfacies and the pyroclastic sedimentary rocks containing terrigenous clast subfacies are favorable subaqueous eruptive facies for reservoirs in continental lacustrine basins. 展开更多
关键词 continental lacustrine basin Songliao Basin Chaganhua area Cretaceous Huoshiling Formation subaqueous eruption volcanic facies tuff cone
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Derivation of the Spiral Motion of an Eruptive Prominence and Its Explanation
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作者 Xiao-Ma Gu Shu-Hua Zhong +1 位作者 Hong-Fei Liang La-Sheng Zhan 《Chinese Journal of Astronomy and Astrophysics》 CSCD 2006年第5期617-624,共8页
A 2D velocity field of the eruptive prominence (EP) of 1991 March 5 is obtained from its spectral data observed at the Yunnan Observatory and the velocity distributions along the entrance slit are derived for differ... A 2D velocity field of the eruptive prominence (EP) of 1991 March 5 is obtained from its spectral data observed at the Yunnan Observatory and the velocity distributions along the entrance slit are derived for different observing frames. Under the assumption that matter in the EP undergoes axial, radial and possible rotational motions, we construct a theoretical velocity distribution of the EP along the entrance slit, to derive, by fitting, the angular velocity of rotation ω and the other three parameters (axial velocity v0, radial velocity vr and the angle between the EP plane and the line of sight Ф). We found: an averaged angular velocity ω of 3.0 × 10^-3 arc s^-1 and the variation of ω with the height above the solar limb. As the EP rises, the matter within it in fact moves along a spiral path around its axis. The spiral motion may be explained by the theory of plasma ‘double pole diffusion' (DPD) caused by a sharp density gradient between the eruptive prominence and the surrounding corona. A theoretical angular velocity ω′ is estimated based on the DPD and basically coincides with ω obtained from the optimal velocity fitting. 展开更多
关键词 SUN eruptive prominence -- Sun Spiral motion
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Diagnostic imaging:Morphological and eruptive disturbances in the permanent teeth
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作者 Deepak Sharma Ramneet Kaur +2 位作者 Suneet Monga Simerjeet Kaur Ruchika Kundra 《World Journal of Stomatology》 2015年第2期72-80,共9页
This paper reviewed the literature on newer threedimensional imaging techniques and their applications in diagnosis and treatment planning of various dental anomalies. Developmental anomalies can occur during any of t... This paper reviewed the literature on newer threedimensional imaging techniques and their applications in diagnosis and treatment planning of various dental anomalies. Developmental anomalies can occur during any of the developmental stages and are manifested clinically after the tooth is fully formed. These dental anomalies may involve a single tooth, a group of teeth, or the entire dentition. Two-dimensional diagnosticimaging, including periapical, occlusal, panoramic, or cephalometric radiographs are essential in localization and management of morphological and eruptive disorders. However, due to their inherent limitations such as insufficient precision because of unusual projection errors and lack of information about spatial relationships, these methods are considered unreliable. Thus, the use of newer image acquisition techniques that allow comprehensive three dimensional imaging and visualization of dental abnormalities is highly recommended for making a confirmatory diagnosis. The significance of accurate endodontic, surgical and orthodontic treatment planning in dental abnormalities cannot be overstated as it pertains to critical anatomic landmarks such as proximity to adjacent teeth or the mandibular canal. The precise information on spatial relationships provided by multiplanar imaging helps the dental surgeon to establish more accurate diagnosis, management strategies and also increases the patient safety. This review highlights the use of high-end diagnostic imaging modalities in diagnosis of the various morphologic and eruptive dental abnormalities. 展开更多
关键词 Three-dimensional IMAGING Spiral COMPUTED TOMOGRAPHY Magnetic resonance IMAGING eruptive MALFORMATIONS MORPHOLOGICAL disturbances Conebeam COMPUTED TOMOGRAPHY
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Eruptive Variables
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作者 Angel Fierros Palacios 《Journal of High Energy Physics, Gravitation and Cosmology》 2016年第2期155-160,共6页
In this paper, a solution of the problem about how a massive star knows that it gets rid of its excess of mass before it can become a white dwarf, a pulsar or a black hole, is proposed. Many astronomers believe that t... In this paper, a solution of the problem about how a massive star knows that it gets rid of its excess of mass before it can become a white dwarf, a pulsar or a black hole, is proposed. Many astronomers believe that this may take place in the form of a nova and supernova outburst, as well as in the form of a continuous outflow of gas [1]. 展开更多
关键词 eruptive Variables
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A comparison study of a solar active-region eruptive filament and a neighboring non-eruptive filament 被引量:2
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作者 Chao-Wei Jiang Shi-Tsan Wu +1 位作者 Xue-Shang Feng Qiang Hu 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2016年第1期151-158,共8页
Solar active region (AR) 11283 is a very magnetically complex region and it has produced many eruptions. However, there exists a non-eruptive filament in the plage region just next to an eruptive one in the AR, whic... Solar active region (AR) 11283 is a very magnetically complex region and it has produced many eruptions. However, there exists a non-eruptive filament in the plage region just next to an eruptive one in the AR, which gives us an opportunity to perform a comparison analysis of these two filaments. The coronal magnetic field extrapolated using our CESE-MHD-NLFFF code reveals that two magnetic flux ropes (MFRs) exist in the same extrapolation box supporting these two filaments, respectively. Analysis of the magnetic field shows that the eruptive MFR contains a bald-patch separatrix surface (BPSS) co- spatial very well with a pre-eruptive EUV sigmoid, which is consistent with the BPSS model for coronal sigmoids. The magnetic dips of the non-eruptive MFRs match Hα observation of the non-eruptive filament strikingly well, which strongly supports the MFR-dip model for filaments. Compared with the non-eruptive MFR/filament (with a length of about 200 Mm), the eruptive MFR/filament is much smaller (with a length of about 20 Mm), but it contains most of the magnetic free energy in the extrapolation box and holds a much higher free energy density than the non-eruptive one. Both the MFRs are weakly twisted and cannot trigger kink instability. The AR eruptive MFR is unstable because its axis reaches above a critical height for torus instability, at which the overlying closed arcades can no longer confine the MFR stably. On the contrary, the quiescent MFR is very firmly held by its overlying field, as its axis apex is far below the torus-instability threshold height. Overall, this comparison investigation supports that an MFR can exist prior to eruption and the ideal MHD instability can trigger an MFR eruption. 展开更多
关键词 magnetic fields -- Sun: corona -- Sun: filaments -- Sun: eruptions
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Variations in the Patterns of Precipitation in the Watershed of the Ambato River Associated with the Eruptive Process of the Tungurahua Volcano in Ecuador
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作者 Iván Ríos García Abel Solera 《Open Journal of Modern Hydrology》 2015年第4期121-139,共19页
The Tungurahua, located in the Cordillera de los Andes, is the volcano with the most eruptive activity in Ecuador nowadays. 1993 records the eruptive initial process and in August of 1999, after almost 80 years of res... The Tungurahua, located in the Cordillera de los Andes, is the volcano with the most eruptive activity in Ecuador nowadays. 1993 records the eruptive initial process and in August of 1999, after almost 80 years of rest, the volcano begins an explosive eruptive period. This research examines the effects of the eruptive process of the volcano in the patterns of change in precipitation in the short term in a hydrographic watershed. Their results are intended to contribute to the studies carried out to understand the weather and the factors influencing its variability at local and global level. It aims also to contribute with technical data in the debate about experimenting with artificial volcanoes to weather modification. The analysis demonstrates a process of redistribution of rainfall, with significant increases in rainfall from 42.25% on December, and significant decreases of 40.03% on September, during the presence of the eruptive process. 展开更多
关键词 VOLCANIC ERUPTION RAINFALL Variability Tungurahua
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Hydrothermal Alteration of Basaltic Rocks at Eruptive Vents on Mount Cameroon Volcano, West Africa
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作者 Akumbom Vishiti Taboko Armstrong +2 位作者 Elisha Mutum Shemang Jacques Etame Cheo Emmanuel Suh 《International Journal of Geosciences》 2018年第9期513-527,共15页
The study of changes in rocks due to interaction with hydrothermal fluids at active volcanoes provides insights into wall rock alteration associated with ore deposits formed in the geological past. Therefore, the natu... The study of changes in rocks due to interaction with hydrothermal fluids at active volcanoes provides insights into wall rock alteration associated with ore deposits formed in the geological past. Therefore, the nature of mineral alteration and chemical changes experienced by wall rocks can be investigated at eruptive sites on active volcanoes and the results used to better constrain ore-forming processes. In this study, we investigated the alteration at eruptive sites at Mount Cameroon volcano. These eruptive vents lie along NE-SW-trending fissures that define the Mount Cameroon rift. The vents are surrounded by cones composed largely of pyroclastic materials and to a lesser extent lava. Fumaroles (volcanic gases) rising through the vents during and after the 1999 eruption have resulted in the alteration of the pyroclastic robble along the fissures and the inner walls of the cones. Consequently, altered basaltic materials are covered with thin films of reddish, yellowish to whitish secondary minerals. These coatings result from an interaction between the surfaces of the basaltic glass with volcanically-derived acidic fluids. Petrographic investigations and XRD analysis of the basalts have identified primary mineral phases, such as olivine, pyroxene (mainly augite) and feldspars. Alteration products revealed include ubiquitous silica as well as gypsum, magnetite, feldspar, alunite and jarosite. Jarosite occurrence indicates that SO2 is the primary volcanically-derived acid source involved in coating formation. High contents of sulfur identified in the basalts indicate that melts at Mount Cameroon can be sulfur saturated as backed by previous melt inclusion data. Whole rock geochemical analysis shows a gain in silica in the altered samples and this ties with the mass balance calculations although minor gains of Al2O3, , MgO, MnO, CaO and K2O are shown by some samples. 展开更多
关键词 Mount Cameroon 1999 ERUPTION Fumarole Wall Rock ALTERATION Mass Bal-ance
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A combined geophysical and lithological study on eruptive history and Quaternary lacustrine stratigraphy of a maar in Leizhou Peninsula, China 被引量:2
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作者 Cong Chen Zhuo Zheng +3 位作者 Li-Feng Zeng Fan Xiao Li-Ping Tian Kang-You Huang 《Journal of Palaeogeography》 SCIE CSCD 2021年第1期98-111,共14页
As the second common type of volcanic vent on Earth, maar-diatreme volcanoes and their post-eruptive lacustrine sediments are a main focus of volcanology, palaeolimnology, palaeoclimatology and palaeontology. A number... As the second common type of volcanic vent on Earth, maar-diatreme volcanoes and their post-eruptive lacustrine sediments are a main focus of volcanology, palaeolimnology, palaeoclimatology and palaeontology. A number of maar-type volcanoes have been found in Leizhou Peninsula, South China, but little is known about their eruption processes and detailed stratigraphy of the post-eruptive sediments. We present a combined geophysical and geological analysis to study the eruptive history and post-eruptive sediment stratigraphy of a large maar, the elliptical(1.8 × 3.0 km^(2)) Jiudouyang(JDY) maar. The lacustrine stratigraphy revealed by drilling cores shows that the JDY maar lake has three major stages of evolution:(i) deep-lake sedimentary environment characterized by high autochthonous diatom productivity;(ii) shallow lake to swamp with very low water levels, characterized by a high total organic carbon(TOC) and abundant wood fragments;and,(iii) intermittent shallow lake and alluvial deposits composed of clay minerals and sand. The electrical resistivity tomography(ERT) values and lithological features are highly consistent, which clearly reveal the presence of ca. 50 m thick lacustrine sediments, directly underlain by a ca. 70 m thick basaltic lava rather than diatreme breccia in the crater. This infill sequence implies an alternation of eruption style from phreatomagmatic to Strombolian and/or lava flow, due to high magma flux and ascent rate of the Hainan Plume during the middle Pleistocene. The ERT data also reveal the initial phreatomagmatic crater floor at ca. 120 m depth. The initial crater had a large diameter/depth ratio(ca. 17), with an elongated shape(major axis to minor axis = 0.6), implying possible lateral vent migration during the eruption. A significant erosion under tropical weathering condition during the last few hundred thousand years, accounted for the large size of the maar crater. The study provides insights into the eruptive history and post-eruptive evolution of a large maar, as well as the spatial distribution of the lacustrine sediments. 展开更多
关键词 Maar crater eruptive history Infill sequence Lake evolution Lacustrine stratigraphy Leizhou Peninsula
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Eruptive Cutaneous Collagenoma: Report of Two Cases 被引量:1
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作者 Jian Wu Mei-Hong Cai +4 位作者 Ling-Ling Chen Lei Wu Xiao-Jian Chen Hong-Yan Zhu Feng Shi 《International Journal of Dermatology and Venereology》 2021年第2期128-130,共3页
Introduction:Eruptive cutaneous collagenoma is non familial connective tissue nevi of unknown etiology presented with an abrupt onset.To date,the literatures on eruptive cutaneous collagenoma are extremely rare in chi... Introduction:Eruptive cutaneous collagenoma is non familial connective tissue nevi of unknown etiology presented with an abrupt onset.To date,the literatures on eruptive cutaneous collagenoma are extremely rare in china.Case present:Two women presented with multiple asymptomatic,skin-colored papules and nodules on the trunk and extremities with no systemic involvement.Histopathology revealed dense,coarse collagen fibers by hematoxylin-esoin stain and decreased,fragmented elastic fibers by Elastic stain compared with the normal skin.Basing on these findings,the diagnosis of eruptive cutaneous collagenoma was made.No specific treatment was given.Discussion:Eruptive cutaneous collagenoma is a very rare dermatosis that is often misdiagnosed as other connective tissue nevi.The pathogenesis is unclear,and also no efficient treatment is available.It is usually diagnosed based on clinical and histopathological findings.Conclusion:The present cases are relatively rare type of eruptive cutaneous collagenoma that provide more experience for clinician,and may be helpful for them to make correct diagnosis for suspicious cases. 展开更多
关键词 case report eruptive cutaneous collagenoma chinese women trunk and extremities
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Southern Hemisphere Volcanism Triggered Multi-year La Niñas during the Last Millennium
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作者 Shangrong ZHOU Fei LIU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第4期587-592,共6页
To explain the recent three-year La Niña event from 2020 to 2022,which has caused catastrophic weather events worldwide,Fasullo et al.(2023)demonstrated that the increase in biomass aerosol resulting from the 201... To explain the recent three-year La Niña event from 2020 to 2022,which has caused catastrophic weather events worldwide,Fasullo et al.(2023)demonstrated that the increase in biomass aerosol resulting from the 2019-20 Australian wildfire season could have triggered this multi-year La Niña.Here,we present compelling evidence from paleo-proxies,utilizing a substantial sample size of 26 volcanic eruptions in the Southern Hemisphere(SH),to support the hypothesis that ocean cooling in the SH can lead to a multi-year La Niña event.This research highlights the importance of focusing on the Southern Ocean,as current climate models struggle to accurately simulate the Pacific response driven by the Southern Ocean. 展开更多
关键词 volcanic eruptions multi-year La Niñas Australian wildfire southern ocean cooling
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Application and prospect of the fluid cooling system of solar arrays for probing the Sun
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作者 Kangli Bao Xiaofei Zhu +5 位作者 Jianchao Feng Liu Liu Xiaofeng Zhang Zhiming Cai Jun Lin Yonghe Zhang 《Astronomical Techniques and Instruments》 CSCD 2024年第1期62-70,共9页
The Solar Close Observations and Proximity Experiments(SCOPE)mission,which has been proposed by the Yunnan Observatories,Chinese Academy of Sciences,aiming to operate at a distance of 5 to 10 solar radii from the Sun,... The Solar Close Observations and Proximity Experiments(SCOPE)mission,which has been proposed by the Yunnan Observatories,Chinese Academy of Sciences,aiming to operate at a distance of 5 to 10 solar radii from the Sun,plans to complete the in situ detection of the solar eruption process and observation of the magnetic field structure response.The solar flux received by the satellite ranges from 10^(3) to 10^(6) Wm^(-2),which poses challenges for thermal management of the solar arrays.In this work,the solar array cooling system of the Parker Solar Probe is discussed,the developments of the fluid loop technique are reviewed,and a research plan for a next-generation solar array cooling system is proposed.This paper provides a valuable reference for novel thermal control systems in spacecraft for solar observation. 展开更多
关键词 In situ detection of solar eruption Solar array cooling system Pumped fluid loop High heat flux dissipation
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Using a Gaussian mathematical model to define eruptive stages of young volcanic rocks in Tengchong based on laser 40Ar/39Ar dating
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作者 Xinwei ZHAO Jing ZHOU +2 位作者 Fang MA Jianqing JI Alan DEINO 《Science China Earth Sciences》 SCIE EI CAS CSCD 2020年第5期662-673,共12页
Reconstruction of Quaternary environments,late Cenozoic geodynamics and evaluation of volcanic hazards,all depend on the precise delineation of eruptive stages.In recent years,laser 40Ar/39Ar dating methods have been ... Reconstruction of Quaternary environments,late Cenozoic geodynamics and evaluation of volcanic hazards,all depend on the precise delineation of eruptive stages.In recent years,laser 40Ar/39Ar dating methods have been widely used for dating young volcanic rocks,given their stable automated testing process,very low background level and high sensitivity,which meet the requirements for precise dating of young samples.This paper applied high-precision laser 40Ar/39Ar dating to the main volcanic units in the Tengchong area and obtained ages in the range of 0.025–5.1 Ma using conventional data processing methods.However,conventional dating highlighted issues related to very low radiogenic 40Ar content,accidental errors and poor data stability,which led to huge age deviations.Moreover,lacking a unified timescale,conventional methods were unable to strictly define the stages of the Tengchong volcanic eruptions,leading to ongoing controversy.In this study,we applied a Gaussian mathematical model to deal with all 378 original ages from 13 samples.An apparent age-probability diagram,consisting of three independent waveforms,have been obtained.The corresponding isochron ages of these three waveforms suggest there were three volcanic eruptive stages,namely during the Pliocene(3.78±0.04 Ma),early Middle Pleistocene(0.63±0.03 Ma)and late Middle Pleistocene to early Late Pleistocene(0.139±0.005 Ma).These results accurately define eruptive stages in the Tengchong area. 展开更多
关键词 LASER 40AR/39AR DATING GAUSSIAN mathematical model eruptive STAGES Apparent age-probability diagram Age deviations Isochron age
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Eruptive xanthomas associated with diabetes mellitus
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作者 Ivana Binic Aleksandar Jankovic 《Chinese Medical Journal》 SCIE CAS CSCD 2009年第17期2074-2075,共2页
Diabetes mellitus (DM) is a most common endocrine disorder and it is characterized by high serum glucose levels and by disturbance of lipid metabolism. As a result, the patients can develop long-term systemic compli... Diabetes mellitus (DM) is a most common endocrine disorder and it is characterized by high serum glucose levels and by disturbance of lipid metabolism. As a result, the patients can develop long-term systemic complications. Numerous skin lesions are associated with either type 1 or type 2 diabetes mellitus, and they are specific chronic complications of the disease. Cutaneous xanthomas result from deposition of lipids in the histiocytes in the dermis or subcutaneous tissue. Eruptive xanthomas are a characteristic, but uncommon complication of diabetes mellitus associated with a more sustained hyperlipidemia affecting plasma triglycerides and cholesterol, and hyperglycemia with glycosuria. 展开更多
关键词 eruptive xanthomas diabetes mellitus HYPERTRIGLYCERIDEMIA HYPERCHOLESTEROLEMIA
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Distribution, geochemistry and age of the Millennium eruptives of Changbaishan volcano, Northeast China - A review 被引量:10
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作者 Chunqing SUN Haitao YOU +3 位作者 Jiaqi LIU Xin LI Jinliang GAO Shuangshuang CHEN 《Frontiers of Earth Science》 SCIE CAS CSCD 2014年第2期216-230,共15页
Large explosive volcanic eruptions generate extensive regional tephra deposits that provide favorable conditions for identifying the source of volcanoes, comparing the sedimentary strata of a region and determining th... Large explosive volcanic eruptions generate extensive regional tephra deposits that provide favorable conditions for identifying the source of volcanoes, comparing the sedimentary strata of a region and determining their ages. The tephra layer, referred to as B- Tm, generated by the Millennium eruption of Chang- baishan volcano, is widely distributed in Northeast China, Japan, D.P.R. Korea, and the nearby coastal area of Russia. It forms part of the widespread northeast Asian strata and is significant for establishing an isochronal stratigraphic framework. However, research on the temporal characterization and stratigraphic correlation of associated strata using this tephra layer is mainly concentrated in and near Japan. In northeastern China, this tephra layer is seldom seen and its application in stratigraphic correlations is even rarer. More importantly, the determination of accurate ages for both distal and proximal tephras has been debated, leading to controversy in discussions of its environmental impacts. Stratigraphic records from both distal and proximal Changbaishan ash show that this eruption generally occurred between 1,012 and 1,004 cal yr BP. Geochemical comparison between Changbaishan ash and the Quaternary widespread ash around Japan illustrates that Changbaishan ash is a continuous composition from rhyolitic to trachytic and its ratio of FeOT to CaO is usually greater than 4, which can be used as a distinguishing identifier among worldwide contemporary eruptions. 展开更多
关键词 Millennium eruption Changbaishan volcano tephrochronology B-Tm tephra
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Comprehensive analysis of pure-quartic soliton dynamics in a passively mode-locked fiber laser 被引量:1
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作者 刘列 韩颖 +3 位作者 霍佳雨 文红琳 吴戈 高博 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第11期477-483,共7页
The understanding of soliton dynamics promotes the development of ultrafast laser technology. High-energy purequartic solitons(PQSs) have gradually become a hotspot in recent years. Herein, we numerically study the in... The understanding of soliton dynamics promotes the development of ultrafast laser technology. High-energy purequartic solitons(PQSs) have gradually become a hotspot in recent years. Herein, we numerically study the influence of the gain bandwidth, saturation power, small-signal gain, and output coupler on PQS dynamics in passively mode-locked fiber lasers. The results show that the above four parameters can affect PQS dynamics. Pulsating PQSs occur as we alter the other three parameters when the gain bandwidth is 50 nm. Meanwhile, PQSs evolve from pulsating to erupting and then to splitting as the other three parameters are altered when the gain bandwidth is 10 nm, which can be attributed to the existence of the spectral filtering effect and intra-cavity fourth-order dispersion. These findings provide new insights into PQS dynamics in passively mode-locked fiber lasers. 展开更多
关键词 pure-quartic soliton pulsating soliton erupting soliton passively mode-locked fiber lasers
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Geochronology,Eruption Sequence and Geochemistry of Mid-Late Jurassic Volcanics South of Manzhouli:Petrogenesis and Implications for Mesozoic Tectonic Regime Transformation
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作者 BAI Yuling WANG Tao +2 位作者 WANG Zongqi YAN Jie ZHANG Ai 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2023年第4期1112-1131,共20页
To the south of Manzhouli,Hulunbuir,Inner Mongolia,experienced a tectonic regime transformation from compression to extension in the mid-Mesozoic.Based on systematic research of the volcanics,petrology,volcanic facies... To the south of Manzhouli,Hulunbuir,Inner Mongolia,experienced a tectonic regime transformation from compression to extension in the mid-Mesozoic.Based on systematic research of the volcanics,petrology,volcanic facies,chronology and geochemistry of rocks in the Buridun area,two stages of volcanics are identified.The first stage named the trachyte series was formed in the late Middle Jurassic(167-163 Ma),its eruption rhythm is pyroxene trachyandesite-trachyandesite-trachyte,and its origin rock is basic volcanics from thickened lower crust,with a tectonic setting in the collision orogeny after the closure of the Mongolia Okhotsk Ocean(MOO).The second stage is a bimodal volcanic rock,formed in the early Late Jurassic(163-160 Ma).The eruption rhythm of basic volcanics in this stage is basaltic andesite-basalt-olivine basalt,which comes from the metasomatized lithospheric mantle,the acidic volcanics of which being characterized by the eruption rhythm of sedimentary-explosive-overflow facies,which came from the partial melting of newly formed lower crust,and this shows the characteristics of A-type granite;the tectonic setting is extension of the lithosphere after collision and closure of the MOO.The changes in the formation age and tectonic setting of the two stages of volcanics demonstrate that the transition time from the compressive system to the extensional system south of Manzhouli is about 163 Ma. 展开更多
关键词 TECTONICS GEOCHRONOLOGY Middle-Late Jurassic volcanics eruption sequence Inner Mongolia
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Nepheloid layer generation by gas eruption:unexpected experimental results
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作者 Chaoqi ZHU Sanzhong LI +6 位作者 Jiangxin CHEN Dawei WANG Xiaoshuai SONG Zhenghui LI Bo CHEN Hongxian SHAN Yonggang JIA 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第2期769-777,共9页
Knowledge of nepheloid layers is important to improve the understanding of physical,geological,and sedimentary processes from continental shelf to abyssal environments.We had not tried to study the nepheloid layers in... Knowledge of nepheloid layers is important to improve the understanding of physical,geological,and sedimentary processes from continental shelf to abyssal environments.We had not tried to study the nepheloid layers in a hydrate-associated tank until unexpected results occurred.Tank experimental results show that gas eruptions triggered intermediate nepheloid layers.Thus,we proposed a new mechanism of intermediate nepheloid layer generation by eruptions.The intermediate nepheloid layers were generated in uniform-density fluid,which indicated that stratified fluid is not a necessary condition for intermediate nepheloid layers.Sufficient space for advection and an oblique slope for detachment are the key ingredients for intermediate nepheloid layer generation by eruptions.Our experiments also offer a new experimental evidence for bottom nepheloid layer generation by earthquakes.Given the scale effects of laboratory experiment,it is important to determine whether submarine volcanic eruption or hydrate-associated venting causes intermediate nepheloid layer in the nature. 展开更多
关键词 intermediate nepheloid layer gas eruption bottom nepheloid layer gas hydrate tank experiment seafloor instability
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全球海啸相关研究进展综述
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作者 程思学 刘海江 《哈尔滨工程大学学报(英文版)》 CSCD 2023年第1期14-24,共11页
With the advancement of the global economy,the coastal region has become heavily developed and densely populated and suffers significant damage potential considering various natural disasters,including tsunamis,as ind... With the advancement of the global economy,the coastal region has become heavily developed and densely populated and suffers significant damage potential considering various natural disasters,including tsunamis,as indicated by several catastrophic tsunami disasters in the 21st century.This study reviews the up-to-date tsunami research from two different viewpoints:tsunamis caused by different generation mechanisms and tsunami research applying different research approaches.For the first issue,earthquake-induced,landslide-induced,volcano eruption-induced,and meteorological tsunamis are individually reviewed,and the characteristics of each tsunami research are specified.Regarding the second issue,tsunami research using post-tsunami field surveys,numerical simulations,and laboratory experiments are discussed individually.Research outcomes from each approach are then summarized.With the extending and deepening of the understanding of tsunamis and their inherent physical insights,highly effective and precise tsunami early warning systems and countermeasures are expected for the relevant disaster protection and mitigation efforts in the coastal region. 展开更多
关键词 Earthquake induced tsunami Landslide induced tsunami Volcano eruption induced tsunami Meteorological tsunami Post-tsunami field survey Numerical modeling Laboratory experiment
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Coupling between the Cenozoic west Pacific subduction initiation and decreases of atmospheric carbon dioxides
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作者 Guozhi Xie Fanfan Tian +3 位作者 Kun Wang Yuanyuan Xiao Tianyu Chen Weidong Sun 《Acta Geochimica》 EI CAS CSCD 2023年第3期387-392,共6页
At the beginning of the Cenozoic,the atmospheric CO_(2)concentration increased rapidly from~2000 ppmv at 60 Ma to~4600 ppmv at 51 Ma,which is 5–10 times higher than the present value,and then continuous declined from... At the beginning of the Cenozoic,the atmospheric CO_(2)concentration increased rapidly from~2000 ppmv at 60 Ma to~4600 ppmv at 51 Ma,which is 5–10 times higher than the present value,and then continuous declined from~51 to 34 Ma.The cause of this phenomenon is still not well understood.In this study,we demonstrate that the initiation of Cenozoic west Pacific plate subduction,triggered by the hard collision in the Tibetan Plateau,occurred at approximately 51 Ma,coinciding with the tipping point.The water depths of the Pacific subduction zones are mostly below the carbonate compensation depths,while those of the Neo-Tethys were much shallower before the collision and caused far more carbonate subducting.Additionally,more volcanic ashes erupted from the west Pacific subduction zones,which consume CO_(2).The average annual west Pacific volvano eruption is 1.11 km~3,which is higher than previous estimations.The amount of annual CO_(2)absorbed by chemical weathering of additional west Pacific volcanic ashes could be comparable to the silicate weathering by the global river.We propose that the initiation of the western Pacific subduction controlled the long-term reduction of atmospheric CO_(2)concentration. 展开更多
关键词 Subduction initiation in the west Pacific Collision of the Neo-Tethys Volcano eruption rates Cenozoic CO_(2)declining Carbonate compensation depths Chemical weathering
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