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The Qixiangzhan Lava Flow at the Tianchi Volcano:Eruptive Dynamics,Emplacement Mechanism and Implications for the Formation of Long-lived Magmatic Systems Prior to Caldera-forming Eruptions 被引量:1
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作者 LI Jiahui SHAN Xuanlong +5 位作者 YI Jian WU Chengzhi Ventura GUIDO LIU Pengcheng GUO Jiannan WANG Wei 《Acta Geologica Sinica(English Edition)》 2025年第1期114-125,共12页
The 7 ka old Qixiangzhan lava flow(QXZ,Tianchi volcano)represents the last eruptive event before the 946 CE,caldera-forming‘Millennium’eruption(ME).Petrographic,whole rock,mineral composition,Sr-Nd isotopic data on ... The 7 ka old Qixiangzhan lava flow(QXZ,Tianchi volcano)represents the last eruptive event before the 946 CE,caldera-forming‘Millennium’eruption(ME).Petrographic,whole rock,mineral composition,Sr-Nd isotopic data on QXZ show that:(a)the lava consists of two components,constituted by comenditic obsidian fragments immersed in a continuous,aphanitic component;(b)both components have the same geochemical and isotopic variations of the ME magma.The QXZ and ME comendites result from fractional crystallization and crustal assimilation processes.The temperature of the QXZ magma was about 790℃ and the depth of the magma reservoir around 7 km,the same values as estimated for ME.QXZ had a viscosity of 10^(5.5)-10^(9) Pa s and a velocity of 3-10 km/yr.The emplacement time was 0.5-1.6yr and the flow rate 0.48-1.50 m^(3)/s.These values lie within the range estimated for other rhyolitic flows worldwide.The QXZ lava originated through a mixed explosive-effusive activity with the obsidian resulting from the ascent of undercooling,degassing and the fragmentation of magma along the conduit walls,whereas the aphanitic component testifies to the less undercooled and segregated flow at the center of the conduit.The QXZ lava demonstrates the extensive history of the ME magma chamber. 展开更多
关键词 lava flow rhyolitic volcanism eruptive mechanism long-lived magmatic systems Tianchi volcano Qixiangzhan Formation
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Sporadic E responds to the 2022 Tonga volcano eruptions recorded by the Meridian Project
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作者 YangYi Sun Tao Yu +1 位作者 Jin Wang Chi Long 《Earth and Planetary Physics》 EI CAS 2025年第1期20-28,共9页
In this study,ionosonde observations over Fuke(19.5°N,109.1°E),Wuhan(30.5°N,114.4°E),and Mohe(53.5°N,122.3°E)were analyzed to demonstrate the responses of the sporadic E()to the severe at... In this study,ionosonde observations over Fuke(19.5°N,109.1°E),Wuhan(30.5°N,114.4°E),and Mohe(53.5°N,122.3°E)were analyzed to demonstrate the responses of the sporadic E()to the severe atmospheric disturbances caused by the Tonga volcanic eruptions on January 15,2022.The most prominent signature was the disappearance of the layer after~10:00 UT over Wuhan and Fuke,which was attributed to the vertical drift caused by the eruptions.The occurred intermittently after 13:00 UT following the arrival of the tropospheric Lamb wave.To examine the causal mechanism for the intermittence,we also included data of horizontal winds in the mesosphere and lower thermosphere region recorded by the meteor radars at Wuhan and Mohe in this study.The wind disturbances with periods of~20 hours contributed to the formation of the layer in the nighttime on January 15. 展开更多
关键词 sporadic E Tonga eruptions neutral wind disturbances
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Mechanism analysis of periostin in osteoclasts differentiation of dental follicle:Two case reports
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作者 Jun Cai Han Qin 《World Journal of Clinical Cases》 2025年第24期86-93,共8页
BACKGROUND This study analyzed the dental follicle and alveolar bone of two patients with tooth eruption disorders,aiming to provide some reference for exploring the etiology and selecting treatment plans of this dise... BACKGROUND This study analyzed the dental follicle and alveolar bone of two patients with tooth eruption disorders,aiming to provide some reference for exploring the etiology and selecting treatment plans of this disease from the perspective of the influence of extracellular matrix on osteoclasts differentiation in dental follicle.CASE SUMMARY Collect dental follicle and alveolar bone tissue from one patient with single tooth eruption disorder and one patient with full permanent tooth eruption disorder,respectively.Simultaneously collect the dental follicle and alveolar bone tissue of obstructed teeth that need to be extracted due to orthodontic treatment as the control group.Hematoxylin and eosin(HE)staining was used to observe the morphology of dental follicle cells.Immunohistochemical staining was used to observe the expression of periostin,receptor activator of nuclear factor kappa B ligand(RANKL),and osteoprotegerin(OPG)protein in dental follicle and alveolar bone tissue.And observe the eruption of teeth after removing resistance from the crown of the permanent tooth germ.CONCLUSION HE staining of two cases of dental follicle tissues showed that the volume of dental follicle cells decreased,the nuclei were condensed,and there seemed to be cellular fibrosis.The immunohistochemical staining showed that both the dental follicle and alveolar bone tissue exhibited increased expression of periostin,decreased expression of RANKL and OPG proteins,and decreased RANKL/OPG ratio.After removing resistance,the permanent tooth germ often appears to have normal eruption.Tooth eruption disorders may be accompanied by abnormal remodeling of periostin,which affects the differentiation function of osteoclasts in the dental follicle and leads to metabolic imbalance of alveolar bone,resulting in tooth eruption disorders.Whether it is a single or full permanent tooth eruption disorder,once the coronal resistance is removed,the teeth can often erupt normally. 展开更多
关键词 Tooth eruption disorder Dental follicle Osteoclast differentiation PERIOSTIN Case report
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Numerical Modelling of Tsunami Waves from Tonga Volcano on January 15,2022
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作者 R.Kh Mazova Jorge Van Den Bosch F. +2 位作者 Gustavo Oses A. Andrey Kurkin Ivan Smirnov 《Journal of Environmental & Earth Sciences》 2025年第2期13-30,共18页
The paper considers a catastrophic event-the eruption of Hunga Tonga-Hunga Ha’apai volcano on January 15,2022.The process of preparation and eruption of Hunga Tonga volcano generated tsunami waves that were observed ... The paper considers a catastrophic event-the eruption of Hunga Tonga-Hunga Ha’apai volcano on January 15,2022.The process of preparation and eruption of Hunga Tonga volcano generated tsunami waves that were observed throughout the World Ocean.This event was notable for its unprecedented global impact and the early appearance of tsunami waves at distant coastal stations.So,the first waves at tide gauge stations in Chile and Peru were recorded 4 hours earlier than the arrival time of tsunami waves to the tide gauge after the eruption of Tonga volcano.Two mechanisms are possible for the generation of early tsunami waves:acoustic Lamb waves generated by a volcanic explosion and submarine landslides that occurred on the slopes of the volcano during the preparatory phase of the eruption.In this study,numerical simulation of various pre-eruption landslide scenarios on the slope of Hunga Tonga volcano is carried out in an attempt to explain these early tsunami waves.Under computation the elastoplastic model of landslide was taken into account.Wave characteristics of a tsunami on the coast of Chile and Peru generated by a landslide process on a volcanic slope are obtained.A detailed comparison of virtual tide gauge data with observational ones is used to validate this model.The results obtained can be used to improve early warning systems. 展开更多
关键词 Volcanic Eruption Landslide Process Acoustic and Tsunami Waves Numerical Simulation Tsunami Wave Characteristics
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Characteristics and distribution patterns of volcanic fractures in the Chaganhua Subsag of the Songliao Basin,China
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作者 Li Ning Shan Xuan-long +5 位作者 Yi Jian Li Zhong-bo Cao Kai-fang Tian Jun Shi Yun-qian Leng Qing-lei 《Applied Geophysics》 2025年第4期1003-1018,1493,共17页
Fractures are critical control factors in volcanic reservoirs.Thus,studies on the prediction and distribution patterns of volcanic fractures are crucial for oil and gas exploration and development.Although considerabl... Fractures are critical control factors in volcanic reservoirs.Thus,studies on the prediction and distribution patterns of volcanic fractures are crucial for oil and gas exploration and development.Although considerable research has been conducted on volcanic fractures,targeted research on the spatial distribution patterns of fracture development remains limited in the literature.Two eruption modes,subaqueous eruption and subaerial eruption,have been identified in the Chaganhua subsag of the Songliao Basin,where gas resources have been discovered.Studying the differences in volcanic fracture development is highly important for understanding the law of oil and gas enrichment in volcanic reservoirs.On the basis of thin sections,cores,electrical imaging logs,and other data obtained from boreholes of subaqueous volcanic eruptions in the Songnan fault depression,we describe the characteristics of drilled fractures in detail and use 3D seismic data to extract intrinsic coherence,ant bodies,and Fourier series to extend the azimuthal anisotropic P-wave reflection coefficient,thereby predicting the spatial distribution of fractures at different scales.Moreover,through statistical analysis of quantitative evaluation indicators,such as fracture density and fracture development rate in different drilling wells,combined with the spatial distribution patterns of the predicted fractures,we compared and analyzed the relationships between the distributions of fractures and volcanic institutions,lithology,and volcanic facies.Results indicate that fractures are more developed in volcanic edifices located closer to faults.Considerable differences in fracture development are observed among lithofacies of volcanic rocks.Near faults,effusion facies,explosive facies and external clastic pyroclastic sedimentary subfacies are favorable for fracture development.This research provides a reference for investigating volcanic rock fractures of the same origins worldwide. 展开更多
关键词 Subaqueous eruption Chaganhua area Volcanic rock Fracture prediction Fourier series Volcanic facies Fracture density Fracture development rate
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Lithofacies palaeogeography,depositional model and shale gas potential evaluation in the O_(3)-S1 Wufeng-Longmaxi Formation in the Sichuan Basin,China
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作者 Xiang-ying Ge Chuan-long Mou +3 位作者 Xin Men Qian Hou Bin-song Zheng Wei Liang 《China Geology》 2025年第2期338-359,共22页
The black shales of Wufeng and Longmaxi Formation(Late Ordovician-Early Silurian period)in Sichuan Basin are the main strata for marine shale gas exploration,which have a yearly shale gas production of 228×10^(8)... The black shales of Wufeng and Longmaxi Formation(Late Ordovician-Early Silurian period)in Sichuan Basin are the main strata for marine shale gas exploration,which have a yearly shale gas production of 228×10^(8)m^(3)and cumulative shale gas production of 919×10^(8)m^(3).According to the lithological and biological features,filling sequences,sedimentary structures and lab analysis,the authors divided the Wufeng/Guanyinqiao and Longmaxi Formations into shore,tidal flat,shoal,shallow water shelf and deep water shelf facies,and confirmed that a shallow water deposition between the two sets of shales.Although both Formations contain similar shales,their formation mechanisms differ.During the deposition of Wufeng shale,influenced by the Caledonian Movement,the Central Sichuan and Guizhou Uplifts led to the transformation of the Sichuan Basin into a back-bulge basin.Coinstantaneous volcanic activity provided significant nutrients,contributing to the deposition of Wufeng Formation black shales.In contrast,during the deposition of Longmaxi shale,collisions caused basement subsidence,melting glaciers raised sea levels,and renewed volcanic activity provided additional nutrients,leading to Longmaxi Formation black shale accumulation.Considering the basic sedimentary geology and shale gas characteristics,areas such as Suijiang-Leibo-Daguan,Luzhou-Zigong,Weirong-Yongchuan,and Nanchuan-Dingshan are identified as key prospects for future shale gas exploration in the Wufeng-Longmaxi Formations. 展开更多
关键词 Shale gas Marine organism Volcanic eruption Sedimentary facies Lithofacies palaeogeography Depositional model Petroleum geological survey engineering Wufeng-Longmaxi Formation Sichuan Basin
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Multidisciplinary Collaborative and Refined Nursing for a Patient with Severe Toxic Epidermal Necrolysis
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作者 Ran Wang Junhua Liang +2 位作者 Juanjuan Ning Zhenzhen Yuan Shuping Gao 《Journal of Clinical and Nursing Research》 2025年第11期80-86,共7页
This paper summarizes the nursing experience of a 75-year-old patient who developed exfoliative dermatitis-type drug eruption induced by cold medicine and progressed to toxic epidermal necrolysis(TEN).The core nursing... This paper summarizes the nursing experience of a 75-year-old patient who developed exfoliative dermatitis-type drug eruption induced by cold medicine and progressed to toxic epidermal necrolysis(TEN).The core nursing measures included(1)Establishing a multidisciplinary team and implementing bundled care led by trauma specialist nurses;(2)Precise wound management using the“three-stage debridement method”and silver ion dressings;(3)Implementing multimodal analgesia based on dynamic pain assessment;(4)Strengthening fluid,electrolyte,and nutritional management;and(5)Providing individualized psychological support.After 14 days of treatment and nursing,the patient’s wounds were completely epithelialized,infection indicators returned to normal,pain was effectively controlled,and the patient was discharged successfully.No serious complications were observed during the 6-month follow-up.For elderly critically ill patients with TEN,constructing a systematic nursing model based on multidisciplinary collaboration and centered on trauma care is crucial for improving patient outcomes. 展开更多
关键词 Toxic epidermal necrolysis Exfoliative dermatitis-type drug eruption Multidisciplinary collaboration Critical care nursing Wound management
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Treatment of class II malocclusion and ectopic maxillary canines:A case report
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作者 Dur Alomair Marwa R Halawani +1 位作者 Shahad Alsubaye Abdulaziz A Almajed 《World Journal of Clinical Cases》 2025年第30期70-79,共10页
BACKGROUND This case report presents an innovative approach to managing a complex class II division 1 malocclusion with ectopic maxillary canines using a modified twin block(TB)appliance.The modification facilitated s... BACKGROUND This case report presents an innovative approach to managing a complex class II division 1 malocclusion with ectopic maxillary canines using a modified twin block(TB)appliance.The modification facilitated simultaneous skeletal correction and canine eruption,reducing treatment time and improving patient satisfaction.CASE SUMMARY A 14-year-old male presented with concerns about a retruded chin and spacing between teeth.Clinical and radiographic evaluation revealed a class II division 1 malocclusion on a moderate class II skeletal base,with palatally impacted maxillary canines.Treatment involved a modified Clark TB appliance designed with hooks to allow active traction of the canines,followed by comprehensive fixed orthodontics.Over 18 months,the patient achieved improved occlusion,corrected overjet and overbite,successful eruption of the impacted canines,and enhanced facial aesthetics.The final results showed significant dental and skeletal improvement without requiring surgical intervention.CONCLUSION A modified TB appliance can effectively manage class II malocclusion with impacted canines in growing patients.The modified approach combining functional mandibular advancement and active canine traction represents a lessdocumented clinical adaptation,offering a valuable,efficient alternative to traditional two-phase interventions. 展开更多
关键词 Orthodontic appliances Functional appliance therapy Ectopic tooth eruption Dental traction Skeletal malocclusion Maxillary canine Growth modification Class II malocclusion Twin block therapy Dental esthetics Case report
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儿童重症药疹临床分析
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作者 张杏莲 《中国药物与临床》 CAS 2016年第2期238-240,共3页
药疹(drug eruption)亦称药物性皮炎,是指药物通过各种途径进入体内(内服、注射、吸入或塞入等)引起的皮肤或黏膜反应,是药物治疗疾病的一种并发症。
关键词 重症药疹 多形红斑型 ERUPTION 黏膜反应 黏膜损害 大疱 致敏药物 内脏损害 解热镇痛药 药物治疗
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Potential Hazards of Eruptions around the Tianchi Caldera Lake, China 被引量:15
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作者 WEIHaiquan HONGHanjing +2 位作者 R.S.J.SPARKS J.S.WALDER HANBin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2004年第3期790-794,共5页
Since the eruption of the Tianchi volcano about 1000 years ago, there have been at least 3 to 5 eruptions of small to moderate size. In addition, hazardous avalanches, rock falls and debris flows have occurred during ... Since the eruption of the Tianchi volcano about 1000 years ago, there have been at least 3 to 5 eruptions of small to moderate size. In addition, hazardous avalanches, rock falls and debris flows have occurred during periods between eruptions. A future eruption of the Tianchi volcano is likely to involve explosive interaction between magma and the caldera lake. The volume of erupted magma is almost in a range of 0.1-0.5 km3. Tephra fallout may damage agriculture in a large area near the volcano. If only 1% of the lake water were ejected during an eruption and then precipitated over an area of 200 km2, the average rainfall would be 100 mm. Moreover, lahars are likely to occur as both tephra and water ejected from the caldera lake fall onto flanks of the volcano. Rocks avalanching into the caldera lake also would bring about grave hazards because seiches would be triggered and lake water with the volume equal to that of the landslide would spill out of the existing breach in the caldera and cause flooding downstream. 展开更多
关键词 Tianchi volcano eruption of small to moderate size SEICHE harzerd NE China
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Delayed hypersensitivity reaction resulting in maculopapular-type eruption due to entecavir in the treatment of chronic hepatitis B 被引量:11
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作者 Jeong Tae Kim Hye Won Jeong +5 位作者 Ki Hwa Choi Tae Young Yoon Nohyun Sung Young Ki Choi Eun Ha Kim Hee Bok Chae 《World Journal of Gastroenterology》 SCIE CAS 2014年第42期15931-15936,共6页
Several clinical trials have demonstrated the potent antiviral efficacy of entecavir (ETV), and this relatively new nucleoside analogue drug has rapidly become a frequently prescribed therapy for chronic hepatitis B (... Several clinical trials have demonstrated the potent antiviral efficacy of entecavir (ETV), and this relatively new nucleoside analogue drug has rapidly become a frequently prescribed therapy for chronic hepatitis B (CHB) worldwide. While the studies have also shown a good overall safety profile for ETV, adverse drug reactions (ADRs) in patients with advanced cirrhosis have been reported and represent a broad spectrum of drug-induced injuries, including lactic acidosis, myalgia, neuropathy, azotemia, hypophosphatemia, muscular weakness, and pancreatitis, as well as immune-mediated responses (i.e., allergic reactions). Cutaneous ADRs associated with ETV are very rare, with only two case reports in the publicly available literature; both of these cases were classified as unspecified hypersensitivity allergic (type I) ADR, but neither were reported as pathologically proven or as evaluated by cytokine release analysis. Here, we report the case of a 45-year-old woman who presented with a generalized maculopapular rash after one week of ETV treatment for lamivudine-resistant CHB. The patient reported having experienced a similar skin eruption during a previous three-month regimen of ETV, for which she had self-discontinued the medication. Histopathological analysis of a skin biopsy showed acanthotic epidermis with focal parakeratosis and a perivascular lymphocytic infiltrate admixed with interstitial eosinophils in the papillary and reticular dermis, consistent with a diagnosis of drug sensitivity. A lymphocyte stimulation test showed significantly enhanced IL-4, indicating a classification of type IVb delayed hypersensitivity. The patient was switched to an adefovir-lamivudine combination regimen and the skin eruption resolved two weeks after the ETV withdrawal. This case represents the first pathologically and immunologically evidenced ETV-induced delayed type hypersensitivity skin reaction reported to date. Physicians should be aware of the potential, although rare, for cutaneous ADRs associated with ETV treatment. 展开更多
关键词 ENTECAVIR Delayed type hypersensitivity Maculopapular drug eruption DERMATOLOGY Adverse drug reaction Chronic hepatitis B
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Research on Full Space Transient Electro-magnetism Technique for Detecting Aqueous Structures in Coal Mines 被引量:24
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作者 YU Jing-cun LIU Zhi-xin TANG Jin-yun 《Journal of China University of Mining and Technology》 EI 2007年第1期58-62,共5页
Based on the transmitting theory of "smoke ring effect", the transient electromagnetism technique was used in coal mines to detect abnormal areas of aquiferous structures in both roofs and floors of coal sea... Based on the transmitting theory of "smoke ring effect", the transient electromagnetism technique was used in coal mines to detect abnormal areas of aquiferous structures in both roofs and floors of coal seams and in front of excavated roadways. Survey devices, working methods and techniques as well as data processing and interpretation are discussed systematically. In addition, the direction of mini-wireframe emission electromagnetic wave of the full space transient electromagnetism technique was verified by an underground borehole for water detection and drainage. The result indicates that this technique can detect both horizontal and vertical development rules of abnormal water bodies to a certain depth below the floor of coal seams and can also detect the abnormal, low resistance water bodies within a certain distance of roofs. Furthermore, it can detect such abnormal bodies in ahead of the excavated roadway front. Limited by the underground environment, the full space transient electromagnetism technique can detect to a depth of only 120 m or so. 展开更多
关键词 water eruption structure water hazard in coal mines detection technique full space transient electromagnetism
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Volcanoes and Climate:Sizing up the Impact of the Recent Hunga Tonga-Hunga Ha'apai Volcanic Eruption from a Historical Perspective 被引量:6
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作者 Meng ZUO Tianjun ZHOU +4 位作者 Wenmin MAN Xiaolong CHEN Jian LIU Fei LIU Chaochao GAO 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2022年第12期1986-1993,共8页
An undersea volcano at Hunga Tonga-Hunga Ha'apai(HTHH)near the South Pacific island nation of Tonga,erupted violently on 15 January 2022.Potential climate impact of the HTHH volcanic eruption is of great concern t... An undersea volcano at Hunga Tonga-Hunga Ha'apai(HTHH)near the South Pacific island nation of Tonga,erupted violently on 15 January 2022.Potential climate impact of the HTHH volcanic eruption is of great concern to the public;here,we intend to size up the impact of the HTHH eruption from a historical perspective.The influence of historical volcanic eruptions on the global climate are firstly reviewed,which are thought to have contributed to decreased surface temperature,increased stratospheric temperature,suppressed global water cycle,weakened monsoon circulation and El Niño-like sea surface temperature.Our understanding of the impacts of past volcanic eruptions on global-scale climate provides potential implication to evaluate the impact of the HTHH eruption.Based on historical simulations,we estimate that the current HTHH eruption with an intensity of 0.4 Tg SO_(2)injection will decrease the global mean surface temperature by only 0.004℃in the first year after eruption,which is within the amplitude of internal variability at the interannual time scale and thus not strong enough to have significant impacts on the global climate. 展开更多
关键词 Hunga Tonga-Hunga Ha'apai volcanic eruption global climate surface temperature MONSOON ENSO
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Role of third molars in orthodontics 被引量:5
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作者 Konstantinia Almpani Olga-Elpis Kolokitha 《World Journal of Clinical Cases》 SCIE 2015年第2期132-140,共9页
The role of third molars in the oral cavity has been extensively studied over the years. Literature includes numerous diagnostic and treatment alternatives regarding the third molars. However, an issue that has not be... The role of third molars in the oral cavity has been extensively studied over the years. Literature includes numerous diagnostic and treatment alternatives regarding the third molars. However, an issue that has not been discussed at the same level is their involvement in orthodontic therapy. The aim of this study is to present a review of the contemporary literature regarding the most broadly discussed aspects of the multifactorial role of third molars in orthodontics and which are of general dental interest too. 展开更多
关键词 CROWDING Extraction ERUPTION THIRD MOLAR ORTHODONTICS IMPACTION
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Loss of epithelial FAM20A in mice causes amelogenesis imperfecta, tooth eruption delay and gingival overgrowth 被引量:5
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作者 Li-Li Li Pei-Hong Liu +4 位作者 Xiao-Hua Xie Su Ma Chao Liu Li Chen Chun-Lin Qin 《International Journal of Oral Science》 SCIE CAS CSCD 2016年第2期98-109,共12页
FAM20A has been studied to a very limited extent. Mutations in human FAM20A cause amelogenesis imperfecta, gingival fibromatosis and kidney problems. It would be desirable to systemically analyse the expression of FAM... FAM20A has been studied to a very limited extent. Mutations in human FAM20A cause amelogenesis imperfecta, gingival fibromatosis and kidney problems. It would be desirable to systemically analyse the expression of FAM20A in dental tissues and to assess the pathological changes when this molecule is specifically nullified in individual tissues. Recently, we generated mice with a Fam2OA-floxed allele containing the beta-galactosidase reporter gene. We analysed FAM20A expression in dental tissues using X-Gal staining, immunohistochemistry and in situ hybridization, which showed that the ameloblasts in the mouse mandibular first molar began to express FAM20A at 1 day after birth, and the reduced enamel epithelium in erupting molars expressed a significant level of FAM2OA. By breeding K14-Cre mice with Fam20An^x/fl^x mice, we created K14-Cre;Fam20Af/flox/flox (conditional knock out, cKO) mice, in which Fam20A was inactivated in the epithelium. We analysed the dental tissues of cKO mice using X-ray radiography: histology and immunohistochemistry. The molar enamel matrix in cKO mice was much thinner than normal and was often separated from the dentinoenamel junction. The Fam2OA-deficient ameloblasts were non-polarized and disorganized and were detached from the enamel matrix. The enamel abnormality in cKO mice was consistent with the diagnosis of amelogenesis imperfecta. The levels of enamelin and matrix metalloproteinase 20 were lower in the ameloblasts and enamel of cKO mice than the normal mice, The cKO mice had remarkable delays in the eruption of molars and hyperplasia of the gingival epithelium. The findings emphasize the essential roles of FAM20A in the development of dental and oral tissues. 展开更多
关键词 conditional knock out mice ENAMEL FAM2OA gingival overgrowth tooth eruption
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Facies Architecture Model of the Shimentan Formation Pyroclastic Rocks in the Block-T Units, Xihu Sag, East China Sea Basin, and its Exploration Significance 被引量:5
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作者 DAI Xiaojuan TANG Huafeng +5 位作者 ZHANG Tao ZHAO Pengjiu XU Chunming KONG Tan ZHAO Tianliang WANG Pujun 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2019年第4期1076-1087,共12页
A gas field consisting of volcanic reservoir rocks was discovered in the block-T units of the Xihu Sag,East China Sea Basin.The lithology of the volcanic rocks is dominated by tuff and reworked tuff.The lithofacies ar... A gas field consisting of volcanic reservoir rocks was discovered in the block-T units of the Xihu Sag,East China Sea Basin.The lithology of the volcanic rocks is dominated by tuff and reworked tuff.The lithofacies are dominated by base surge deposits of explosive facies.As the architecture model of volcanic facies is still uncertain,it has restricted the exploration and development of mineral resources in this area.Using core and cuttings data,the lithology,lithofacies,geochemistry as well as grain size characteristics of volcanic rocks were analyzed.Based on these analyses,the volcanic rocks in the well section are divided into three eruptive stages.The transport direction of each volcanic eruption is analyzed using crystal fragment size analysis.The facies architecture of the block-T units was established based on the reconstruction results of paleo-geomorphology.The results show that the drilling reveals proximal facies(PF)and distal facies(DF)of the volcanic edifices.However,the crater-near crater facies(CNCF)are not revealed.Compared with the reservoirs of the Songliao Basin,it is shown that the volcanic rocks in the Xihu Sag have good exploration potential;a favorable target area is the CNCF near the contemporaneous fault. 展开更多
关键词 volcanic rocks Shimentan Formation facies architecture eruptive stage East China Sea Basin
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The Effect of Super Volcanic Eruptions on Ozone Depletion in a Chemistry–Climate Model 被引量:4
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作者 Luyang XU Ke WEI +3 位作者 Xue WU S. P. SMYSHLYAEV Wen CHEN V. Ya. GALIN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2019年第8期823-836,共14页
With the gradual yet unequivocal phasing out of ozone depleting substances(ODSs), the environmental crisis caused by the discovery of an ozone hole over the Antarctic has lessened in severity and a promising recovery ... With the gradual yet unequivocal phasing out of ozone depleting substances(ODSs), the environmental crisis caused by the discovery of an ozone hole over the Antarctic has lessened in severity and a promising recovery of the ozone layer is predicted in this century. However, strong volcanic activity can also cause ozone depletion that might be severe enough to threaten the existence of life on Earth. In this study, a transport model and a coupled chemistry–climate model were used to simulate the impacts of super volcanoes on ozone depletion. The volcanic eruptions in the experiments were the 1991 Mount Pinatubo eruption and a 100 × Pinatubo size eruption. The results show that the percentage of global mean total column ozone depletion in the 2050 RCP8.5 100 × Pinatubo scenario is approximately 6% compared to two years before the eruption and 6.4% in tropics. An identical simulation, 100 × Pinatubo eruption only with natural source ODSs, produces an ozone depletion of 2.5% compared to two years before the eruption, and with 4.4% loss in the tropics. Based on the model results,the reduced ODSs and stratospheric cooling lighten the ozone depletion after super volcanic eruption. 展开更多
关键词 STRATOSPHERIC ozone VOLCANIC ERUPTIONS STRATOSPHERIC AEROSOLS chemistry–climate model
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Evidence supporting New Geophysics 被引量:7
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作者 Stuart Crampin Yuan Gao 《Earth and Planetary Physics》 2018年第3期173-188,共16页
In the last decade a New Geophysics has been proposed,whereby the crust and uppermost ~400 km of the mantle of the Earth are so pervaded by closely-spaced stress-aligned microcracks(intergranular films of hydrated mel... In the last decade a New Geophysics has been proposed,whereby the crust and uppermost ~400 km of the mantle of the Earth are so pervaded by closely-spaced stress-aligned microcracks(intergranular films of hydrated melt in the mantle) that in situ rocks verge on failure by fracturing,and hence are critical-systems that impose a range of fundamentally-new properties on conventional sub-critical geophysics.Enough of these new properties have been observed to confirm that New Geophysics is a new understanding of fluid/rock deformation with important implications and applications.Evidence supporting New Geophysics has been published in a wide variety of publications.Here,for clarification,we summarise in one document the evidence supporting New Geophysics. 展开更多
关键词 EARTHQUAKES ERUPTIONS MICROCRACKS NEW GEOPHYSICS SHEAR-WAVE splitting stress-forecasting
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Under the surface:Pressure-induced planetary-scale waves,volcanic lightning,and gaseous clouds caused by the submarine eruption of Hunga Tonga-Hunga Ha'apai volcano 被引量:9
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作者 David A.Yuen Melissa A.Scruggs +11 位作者 Frank J.Spera Yingcai Zheng Hao Hu Stephen R.McNutt Glenn Thompson Kyle Mandli Barry R.Keller Songqiao Shawn Wei Zhigang Peng Zili Zhou Francesco Mulargia Yuichiro Tanioka 《Earthquake Research Advances》 CSCD 2022年第3期1-13,共13页
We present a narrative of the eruptive events culminating in the cataclysmic January 15, 2022 eruption of Hunga Tonga-Hunga Ha’apai Volcano by synthesizing diverse preliminary seismic, volcanological, sound wave, and... We present a narrative of the eruptive events culminating in the cataclysmic January 15, 2022 eruption of Hunga Tonga-Hunga Ha’apai Volcano by synthesizing diverse preliminary seismic, volcanological, sound wave, and lightning data available within the first few weeks after the eruption occurred. The first hour of eruptive activity produced fast-propagating tsunami waves, long-period seismic waves, loud audible sound waves, infrasonic waves, exceptionally intense volcanic lightning and an unsteady volcanic plume that transiently reached-at 58km-the Earth’s mesosphere. Energetic seismic signals were recorded worldwide and the globally stacked seismogram showed episodic seismic events within the most intense periods of phreatoplinian activity, and they correlated well with the infrasound pressure waveform recorded in Fiji. Gravity wave signals were strong enough to be observed over the entire planet in just the first few hours, with some circling the Earth multiple times subsequently. These large-amplitude, long-wavelength atmospheric disturbances come from the Earth’s atmosphere being forced by the magmatic mixture of tephra, melt and gasses emitted by the unsteady but quasicontinuous eruption from 0402±1–1800 UTC on January 15, 2022. Atmospheric forcing lasted much longer than rupturing from large earthquakes recorded on modern instruments, producing a type of shock wave that originated from the interaction between compressed air and ambient(wavy) sea surface. This scenario differs from conventional ideas of earthquake slip, landslides, or caldera collapse-generated tsunami waves because of the enormous(~1000x) volumetric change due to the supercritical nature of volatiles associated with the hot,volatile-rich phreatoplinian plume. The time series of plume altitude can be translated to volumetric discharge and mass flow rate. For an eruption duration of ~12 h, the eruptive volume and mass are estimated at 1.9 km^(3) and~2 900 Tg, respectively, corresponding to a VEI of 5–6 for this event. The high frequency and intensity of lightning was enhanced by the production of fine ash due to magma-seawater interaction with concomitant high charge per unit mass and the high pre-eruptive concentration of dissolved volatiles. Analysis of lightning flash frequencies provides a rapid metric for plume activity and eruption magnitude. Many aspects of this eruption await further investigation by multidisciplinary teams. It represents a unique opportunity for fundamental research regarding the complex, non-linear behavior of high energetic volcanic eruptions and attendant phenomena, with critical implications for hazard mitigation, volcano forecasting, and first-response efforts in future disasters. 展开更多
关键词 Hunga Tonga-Hunga Ha'apai Atmospheric pressure wave Tsunami wave Volcanic lightning Phreatoplinian eruption
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The Response of the East Asian Summer Monsoon to Strong Tropical Volcanic Eruptions 被引量:5
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作者 CUI Xuedong GAO Yongqi SUN Jianqi 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2014年第6期1245-1255,共11页
A 600-year integration performed with the Bergen Climate Model and National Centers for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR) reanalysis data were used to investigate the impa... A 600-year integration performed with the Bergen Climate Model and National Centers for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR) reanalysis data were used to investigate the impact of strong tropical volcanic eruptions on the East Asian summer monsoon (EASM) and EASM rainfall.Both the simulation and NCEP/NCAR reanalysis data show a weakening of the EASM in strong eruption years.The model simulation suggests that North and South China experience droughts and the Yangtze-Huaihe River Valley experiences floods during eruption years.In response to strong tropical volcanic eruptions,the meridional air temperature gradient in the upper troposphere is enhanced,which leads to a southward shift and an increase of the East Asian subtropical westerly jet stream (EASWJ).At the same time,the land-sea thermal contrast between the Asian land mass and Northwest Pacific Ocean is weakened.The southward shift and increase of the EASWJ and reduction of the land-sea thermal contrast all contribute to a weakening of the EASM and EASM rainfall anomaly. 展开更多
关键词 East Asian summer monsoon volcanic eruption East Asian subtropical westerly jet stream land-sea thermal contrast
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