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Present-day Upper-crustal Strain Rate Field in Southeastern Tibet and its Geodynamic Implications:Constraints from GPS Measurements with ABIC Method 被引量:1
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作者 YANG Shaohua PAN Jiawei +1 位作者 LI Haibing SHI Yaolin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第1期265-275,共11页
The Earth’s surface kinematics and deformation are fundamental to understanding crustal evolution.An effective research approach is to estimate regional motion field and deformation fields based on modern geodetic ne... The Earth’s surface kinematics and deformation are fundamental to understanding crustal evolution.An effective research approach is to estimate regional motion field and deformation fields based on modern geodetic networks.If the discrete observed velocity field is obtained,the velocity related fields,such as dilatation rate and maximum shear strain rate,can be estimated by applying varied mathematical approaches.This study applied Akaike's Bayesian Information Criterion(ABIC)method to calculate strain rate fields constrained by GPS observations in the southeast Tibetan Plateau.Comparison with results derived from other three methods revealed that our ABIC-derived strain rate fields were more precise.The maximum shear strain rate highlighted the Xianshuihe–Xiaojiang fault system as the main boundary for the outward migration of material in southeastern Tibet,indicating rotation of eastern Tibet material around the eastern Himalaya rather than whole extrusion along a fixed channel.Additionally,distinct dilatation rate patterns in the northeast and southwest regions of the fault system were observed.The northeast region,represented by the Longmenshan area,exhibited negative dilatational anomalies;while the southwest region,represented by the Jinsha River area north of 29°N,displayed positive dilatational anomalies.This indicates compression in the former and extension in the latter.Combined with deep geophysical observations,we believe that the upper and lower crusts of the Jinsha River area north of 29°N are in an entire expanding state,probably caused by the escape-drag effect of material.The presence of a large,low-viscosity region south of 29°N may not enable the entire escape of the crust,but instead result in a differential escape of the lower crust faster than the upper crust. 展开更多
关键词 strain rate differential escape ABIC GPS southeastern Tibet
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Correction:The escape mechanisms of the proto-atmosphere on terrestrial planets:“boil-off”escape,hydrodynamic escape and impact erosion
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作者 Ziqi Wang You Zhou Yun Liu 《Acta Geochimica》 EI CAS CSCD 2024年第3期623-623,共1页
In the original publication of the article,the affiliation“College of Earth and Planetary Sciences,University of Chinese Academy of Sciences,Beijing,People’s Republic of China”for author Ziqi Wang was missing and i... In the original publication of the article,the affiliation“College of Earth and Planetary Sciences,University of Chinese Academy of Sciences,Beijing,People’s Republic of China”for author Ziqi Wang was missing and included in this correction article. 展开更多
关键词 escape PLANET COLLEGE
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Alpha-fetoprotein triggers hepatoma cells escaping from immune surveillance through altering the expression of Fas/FasL and tumor necrosis factor related apoptosis-inducing ligand and its receptor of lymphocytes and liver cancer cells 被引量:35
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作者 Meng-SenLi Qiu-LingMa +4 位作者 QianChen Xin-HuaLiu Ping-FengLi Guo-GuangDu GangLi 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第17期2564-2569,共6页
AIM: To investigate the mechanism of α-fetoprotein (AFP)in escaping from the host immune surveillance of hepatocellular carcinoma.METHODS: AFP purified from human umbilical blood was administrated into the cultured h... AIM: To investigate the mechanism of α-fetoprotein (AFP)in escaping from the host immune surveillance of hepatocellular carcinoma.METHODS: AFP purified from human umbilical blood was administrated into the cultured human lymphoma Jurkat T cell line or hepatoma cell line, Bel7402 in vitro. The expression of tumor necrosis factor related apoptosisinducing ligand (TRAIL) and its receptor (TRAILR) mRNA were analyzed by Northern blot and Western blot wasused to detect the expression of Fas and Fas ligand (FasL)protein.RESULTS: AFP (20 mg/L) could promote the expression of FasL and TRAIL, and inhibit the expression of Fas and TRAILR of Bel7402 cells. For Jurkat cell line, AFP could suppress the expression of FasL and TRAIL, and stimulate the expression of Fas and TRAILR. AFP also could synergize with Bel7402 cells to inhibit the expression of FasL protein and TRAIL mRNA in Jurkat cells. The monoclonal antibody against AFP (anti-AFP) could abolish these functions of AFP.CONCLUSION: AFP is able to promote the expression of FasL and TRAIL in hepatoma cells and enhance the expression of Fas and TRAILR in lymphocytes. These could elicit the escape of hepatocellular carcinoma cells from the host's lymphocytes immune surveillance. 展开更多
关键词 ALPHA-FEtopROTEIN Hepatocellular carcinoma Immune escape
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Analyze Chinese capital escape & international moving capital influx from net errors and omissions in the balance of payments
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作者 CHEN Lu-man HU Jing LIU Jun-qing 《Chinese Business Review》 2008年第9期20-27,34,共9页
With the rapid economic development, the imbalance of China's balance of payments gets sever gradually, especially in the continuous increase in the net errors and omissions, which even has exceeded the international... With the rapid economic development, the imbalance of China's balance of payments gets sever gradually, especially in the continuous increase in the net errors and omissions, which even has exceeded the international alert line. Such scale of net errors and omissions have also presented the flaws of the custody of capital flows, leading to huge capital escape and hot money influx, which needs our attention. 展开更多
关键词 BP net errors and omissions capital escape international moving capital capital custody
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A discussion of escape in <> and <>
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作者 陈劼 《双语学习》 2007年第12M期188-188,190,共2页
通过对James Joyce的《A little Cloud》和Froster的《The Road from Colonus》的讨论,阐述了社会和环境对人的命运那种无可抗争的影响,精彩地阐述了在无奈的社会现实中顿悟的结局。
关键词 社会 环境 命运 影响 乔伊斯 《天边一朵云》 《离开科罗诺斯之路》 福斯特
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Aryl hydrocarbon receptor dynamics in esophageal squamous cell carcinoma:From immune modulation to therapeutic opportunities 被引量:1
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作者 Mina Rahmati Hassan Moghtaderi +1 位作者 Saeed Mohammadi Ahmed Al-Harrasi 《World Journal of Experimental Medicine》 2024年第3期48-56,共9页
Esophageal squamous cell carcinoma(ESCC)is a substantial global health burden.Immune escape mechanisms are important in ESCC progression,enabling cancer cells to escape the surveillance of the host immune system.One k... Esophageal squamous cell carcinoma(ESCC)is a substantial global health burden.Immune escape mechanisms are important in ESCC progression,enabling cancer cells to escape the surveillance of the host immune system.One key player in this process is the Aryl Hydrocarbon Receptor(AhR),which influences multiple cellular processes,including proliferation,differentiation,metabolism,and immune regulation.Dysregulated AhR signaling participates in ESCC development by stimulating carcinogenesis,epithelial-mesenchymal transition,and immune escape.Targeting AhR signaling is a potential therapeutic approach for ESCC,with AhR ligands showing efficacy in preclinical studies.Additionally,modification of AhR ligands and combination therapies present new opportunities for therapeutic intervention.This review aims to address the knowledge gap related to the role of AhR signaling in ESCC pathogenesis and immune escape. 展开更多
关键词 Esophageal squamous cell carcinoma Aryl hydrocarbon receptor Immune escape Tumor microenvironment IMMUNOSUPPRESSION therapeutic targeting
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Escape from the Besieged Fortress——An Analysis of Alice Munro's "Runaway" 被引量:1
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作者 王琴 徐晓娜 《海外英语》 2011年第12X期252-253,共2页
Alice Munro is one of the famous Canadian writers and is renowned above all for the astonishing subtlety of her short stories.Her theme has often been the dilemmas of the female coming to terms with family, friends in... Alice Munro is one of the famous Canadian writers and is renowned above all for the astonishing subtlety of her short stories.Her theme has often been the dilemmas of the female coming to terms with family, friends in a small town. This paper attempts to make a brief introduction about the stories of Alice Munro's Runaway and explores the protagonist's choices in the dilemma situation, and then exposes the cruelty of reality is that they cannot get rid of the ineluctable reality of life. Escape is only a temporary action which cannot save them from endless triviality of life. What they should do is not to escape from life, but to adapt to the reality of life. 展开更多
关键词 ALICE Munro RUNAWAY escape REALITY
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Single-cell RNA-seq reveals the immune escape and drug resistance mechanisms of mantle cell lymphoma 被引量:7
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作者 Liang Wang Steven Mo +2 位作者 Xin Li Yingzhi He Jing Yang 《Cancer Biology & Medicine》 SCIE CAS CSCD 2020年第3期726-739,共14页
Objective:Mantle cell lymphoma(MCL)is a rare subtype of non-Hodgkin lymphoma(NHL)with high heterogeneity and a high recurrence rate.How heterogenous cell populations contribute to relapse remains to be elucidated.Meth... Objective:Mantle cell lymphoma(MCL)is a rare subtype of non-Hodgkin lymphoma(NHL)with high heterogeneity and a high recurrence rate.How heterogenous cell populations contribute to relapse remains to be elucidated.Methods:We performed single cell RNA sequencing(scRNA-seq)on approximately 4,000 bone marrow cells sampled from one patient with multidrug resistant MCL.We identified 10 subpopulations comprising 4 malignant B cell subtypes,3 T cell subtypes,2 dendritic cell subtypes and 1 natural killer(NK)cell subtype.Subsequently,we identified cell markers,including a series of genes associated with immune escape and drug resistance.In addition,we explored the roles of these genes in the mechanism of immune escape and drug resistance,and we verified the expression imbalance and clinical prognostic potential by using GEO datasets including 211 MCL samples.Results:The major immune escape mechanisms of MCL included anti-perforin activity,decreased immunogenicity and direct inhibition of apoptosis and cell killing,as mediated by type I and II B cells.The drug resistance mechanisms of different cell clusters included drug metabolism,DNA damage repair,apoptosis and survival promotion.Type III B cells closely communicate with other cells.The key genes involved in the resistance mechanisms showed dysregulated expression and may have significant clinical prognostic value.Conclusion:This study investigated potential immune escape and drug resistance mechanisms in MCL.The results may guide individualized treatment and promote the development of therapeutic drugs. 展开更多
关键词 Cell heterogeneity immune escape mantle cell lymphoma multidrug resistance scRNA-seq
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Costimulatory Molecule B7-H1 on the Immune Escape of Bladder Cancer and Its Clinical Significance 被引量:7
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作者 王永华 庄乾元 +2 位作者 周四维 胡志全 兰儒竹 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2009年第1期77-79,共3页
B7-H1, a recently described member of the B7 family of costimulatory molecules, is thought to be involved in tumor immune escape by inducing T-cell apoptosis. In order to investigate the relationship between B7-H1 and... B7-H1, a recently described member of the B7 family of costimulatory molecules, is thought to be involved in tumor immune escape by inducing T-cell apoptosis. In order to investigate the relationship between B7-H1 and immune escape of bladder cancer, B7-H1 expression in 50 cases of bladder cancer was detected by using immunohistochemical method. Survival curves were con- structed using the Kaplan-Meier method and independent prognostic factors were evaluated using the Cox regression model. Our results showed that the positive rate of B7-H1 immunostaining in normal bladder tissue and bladder cancer was 0 and 72% respectively. The expression of B7-H1 was strongly associated with the pathological grade, clinical stage and recurrence (P〈0.05). The survival rate was significantly lower in patients with B7-H1 positive group than in those with B7-H1 negative group and multi-variable analysis revealed that B7-H1 could be regarded as an independent factor in evaluating the prognosis of bladder cancer. It is concluded that the expression of B7-H1 is strongly associated with neoplastic progression and prognosis of bladder cancer. The manipulation of B7-H1 may become a beneficial target for immunotherapy in human bladder cancer. 展开更多
关键词 bladder neoplasm costimulatory molecule B7-H1 immune escape
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When Fleeing Matters:Differences in Escape Behaviours of Three Northeast Asian Anurans
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作者 Yoonjung YI Zoljargal PUREVDORJ +2 位作者 Irina MASLOVA Yikweon JANG Amaël BORZÉE 《Asian Herpetological Research》 SCIE CSCD 2024年第1期41-48,共8页
Prey species may have their own optimal escape strategy to balance predation risks and the energetic cost of fleeing.Some species have an advantage when maintaining a short fleeing distance,while others may favour an ... Prey species may have their own optimal escape strategy to balance predation risks and the energetic cost of fleeing.Some species have an advantage when maintaining a short fleeing distance,while others may favour an earlier escape based on microhabitat,size,or body condition.Here,we examined the escape behaviour of the three syntopic Northeast Asian anuran species:Mongolian toads(Strauchbufo raddei),Amur brown frogs(Rana amurensis),and Japanese treefrogs(Dryophytes japonicus)in Mongolia,Russia,China and DPR Korea.We examined flight initiation distance(FID;the distance from a potential predator to the point when the individual starts to flee)and distance fled(DF;distance between flight initiation and flight termination points)of each species and the effects of microhabitat,sex,and body size.Strauchbufo raddei and R.amurensis had a longer FID than D.japonicus,and S.raddei also had a longer DF than D.japonicus.These trends remained similar when dividing FID and DF by a size proxy(snout-vent length)for all individuals.This suggests that the treefrog D.japonicus used a strategy to stay immobile even when they were detected,and the toad S.raddei reacted quicker and more sensitively to predators despite the presence of toxin.Female S.raddei had a significantly longer FID than males suggesting that females are more sensitive to predation risk in this species,but body size was not significant for any of the three species.Our results indicate that the three sympatric species have different escaping strategies,likely related to differences in physiology and crypticity. 展开更多
关键词 AMPHIBIAN distance fled escape behaviour flight initiation distance PREDATION
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Hepatitis B virus subgenotype F3 reactivation with vaccine escape mutations:A case report and review of the literature 被引量:2
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作者 Stefan Schlabe Kathrin van Bremen +7 位作者 Souhaib Aldabbagh Dieter Glebe Corinna M Bremer Tobias Marsen Walter Mellin Veronica Di Cristanziano Anna M Eis-Hübinger Ulrich Spengler 《World Journal of Hepatology》 CAS 2018年第7期509-516,共8页
Hepatitis B represents a global health threat because its chronic course and sequelae contribute to a high morbidity and mortality. Hepatitis B virus(HBV) infection can be controlled by vaccines, antiviral treatment, ... Hepatitis B represents a global health threat because its chronic course and sequelae contribute to a high morbidity and mortality. Hepatitis B virus(HBV) infection can be controlled by vaccines, antiviral treatment, and by interrupting transmission. Rare vaccine escape mutants are serious because they eliminate vaccine protection. Here, we present a 74-year-old vaccinated patient with HBV reactivation 11 years after kidney transplantation. The patient was HBV-positive but HBs Ag-negative prior to vaccination 6 years before transplantation. The reactivated virus was HBV genotype F3 with vaccine escape mutations G145 R, P120 Q, and Q129 P. The patient was successfully treated with entecavir. The epidemiological reasons for this subgenotype, which is extremely rare in Western Europe, were unclear. This case illustrates that second-generation vaccines are not always effective in a specific group of patients. 展开更多
关键词 ENTECAVIR Hepatitis B virus SUBGENOTYPE F3 Kidney transplantation VACCINE escape mutant G145R
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Morphine-3-glucuronide upregulates PD-L1 expression via TLR4 and promotes the immune escape of non-small cell lung cancer 被引量:2
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作者 Kaiyuan Wang Jian Wang +7 位作者 Ting Liu Wenwen Yu Nan Dong Chen Zhang Wenbin Xia Feng Wei Lili Yang Xiubao Ren 《Cancer Biology & Medicine》 SCIE CAS CSCD 2021年第1期155-171,共17页
Objective:Patients with cancer pain are highly dependent on morphine analgesia,but studies have shown a negative correlation between morphine demand and patient outcomes.The long-term use of morphine may result in abn... Objective:Patients with cancer pain are highly dependent on morphine analgesia,but studies have shown a negative correlation between morphine demand and patient outcomes.The long-term use of morphine may result in abnormally elevated serum morphine-3-glucuronide(M3G)levels.Hence,the effects of M3G on tumor progression are worth studying.Methods:The effects of M3G on PD-L1 expressions in human non-small cell lung cancer(NSCLC)cell lines were first evaluated.Activation of TLR4 downstream pathways after M3G treatment was then determined by Western blot.The effects of M3G on human cytotoxic T lymphocytes(CTL)cytotoxicity and INF-γrelease was also detected.Finally,the LLC murine lung adenocarcinoma cell line were used to establish a murine lung cancer model,and the effects of M3G on tumor growth and metastasis were determined.Results:M3G promoted the expressions of PD-L1 in the A549 and H1299 cell lines in a TLR4-dependent manner(P<0.05).M3G activated the PI3 K and the NFκB signaling pathways,and this effect was antagonized by a TLR4 pathway inhibitor.A PI3 K pathway inhibitor reversed the M3G-mediated PD-L1 upregulation.M3G inhibited the cytotoxicity of CTL on A549 cells and decreased the level of INF-γ.Repeated M3G intraperitoneal injections promoted LLC tumor growth and lung metastasis through the upregulation of tumor expressed PD-L1 and the reduction of CTL in the tumor microenvironment.Conclusions:M3G specifically activated TLR4 in NSCLC cells and upregulated PD-L1 expression through the PI3 K signaling pathway,thereby inhibiting CTL cytotoxicity and finally promoting tumor immune escape. 展开更多
关键词 Non-small cell lung cancer TLR4 PD-L1 morphine-3-glucuronide immune escape
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Generalized Newton’s Theory of Universal Gravitation and Black Holes
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作者 Lenser Aghalovyan 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第1期126-137,共12页
The Newton’s theory of universal gravitation is generalized. Significantly strong at short distances central interaction of bodies and particles is established in comparison with Newtonian. A connection is found with... The Newton’s theory of universal gravitation is generalized. Significantly strong at short distances central interaction of bodies and particles is established in comparison with Newtonian. A connection is found with Black Holes, with the horizon of events. Possibility of systematization of all Black Holes is shown. An illustration is given on the example of Black Hole S<sub>gr</sub>A*. 展开更多
关键词 GRAVITATION Central Interaction escape Velocity Black Hole Horizon of Events
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Effect of an escape vent in accordion-shaped traps on the catch and size of Asian paddle crabs Charybdis japonica in an artificial reef area 被引量:2
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作者 张鹏 李超 +1 位作者 李文涛 张秀梅 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2016年第6期1238-1246,共9页
Accordion-shaped traps are widely used in China to catch the Asian paddle crab C harybdis japonica but traps of conventional design often catch juvenile crabs. A new type of accordion-shaped trap with an escape vent(L... Accordion-shaped traps are widely used in China to catch the Asian paddle crab C harybdis japonica but traps of conventional design often catch juvenile crabs. A new type of accordion-shaped trap with an escape vent(L×W=4.3 cm×3.0 cm) was designed and a comparative study between the newly designed and conventional traps was performed in the artifi cial reef area of Zhuwang, Laizhou Bay, China from June to August 2012. The mean catch per unit effort(CPUE) of undersized crabs was signifi cantly lower in the vented traps than in the conventional traps(paired t-test, n =30, P <0.001), while the CPUE of marketable crabs was signifi cantly higher in the vented traps(paired t-test, n =30, P <0.001). The mean size of crabs(carapace length) caught in the vented traps was signifi cantly larger than in conventional traps(paired t-test, n =29, P <0.001). The ratio of undersized crabs was 35.05%±2.57% in conventional traps and 12.53%±0.69% in vented traps(signifi cantly lower, paired t-test, n =29, P <0.001). Therefore, a 4.3 cm×3.0 cm escape vent was considered appropriate for C. japonica fi shing in the artifi cial reef area. This fi nding will assist the development of more sustainable and effi cient crab fi shing methods using accordion-shaped traps. 展开更多
关键词 Charybdis japonica accordion-shaped trap escape vent selectivity artificial reef area
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Escape and Stand of the Pluto Atmosphere
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作者 GAO Chong-Yi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2002年第7期125-127,共3页
Molar mass μmin of the lightest gas, which will exist "forever" in the atmosphere at the planet surface,can be evaluated by Jeans rule. The μmin of Pluto is 17.3 g@ mol-1. It is evident that both N2 and CO... Molar mass μmin of the lightest gas, which will exist "forever" in the atmosphere at the planet surface,can be evaluated by Jeans rule. The μmin of Pluto is 17.3 g@ mol-1. It is evident that both N2 and CO can be major atmospheric composition at the Pluto surface, and will exist "forever". CH4 can only be escaping slowly from Pluto atmosphere, and still holds quite a proportion in current Pluto atmosphere. However, it will not escape from Titan (or Jupiter, Saturn) atmosphere largely, and will exist "forever". Given the quantitylevelof partial pressure of CH4 in Pluto and Titan (or Jupiter, Saturn) original atmosphere is the same, it will be clear that the current partial pressure of CH4 in Pluto surface atmosphere is 10-3 Pa. 展开更多
关键词 PLANET atmosphere PLUTO atmosphere JEANS rule atmospheric composition escape
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Dynamics Analysis and Simulation of the Swiss Lever Escapement Mechanism 被引量:1
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作者 MAO Jian FU Yu 《International Journal of Plant Engineering and Management》 2011年第1期9-14,共6页
Swiss lever escapement is almost always used in all mechanical watches, which is one of the most critical com- ponents in a mechanical watch. However, its dynamics has not been fully studied. This paper presents a met... Swiss lever escapement is almost always used in all mechanical watches, which is one of the most critical com- ponents in a mechanical watch. However, its dynamics has not been fully studied. This paper presents a method for dy- namics analysis and simulation of the Swiss level escapement. First, the Swiss lever escapement mechanism is introduced and its motion in a half-period is divided into four sections. Then the dynamics model is developed using impulsive differ- ential equations and the simulation result is obtained by MATIAB. A watch called Seiko7OO9a is taken as an example. The simulation result shows the dynamic behavior in terms of the relationship among displacement, angle and time. The spring constant and balance wheel inertia that governed the timekeeping accuracy are also discussed. 展开更多
关键词 escapement mechanism dynamics analysis IMPACT SIMULATION
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The escape mechanisms of the proto-atmosphere on terrestrial planets:"boil-off" escape,hydrodynamic escape and impact erosion
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作者 Ziqi Wang You Zhou Yun Liu 《Acta Geochimica》 EI CAS CSCD 2022年第4期592-606,共15页
Atmospheric escape is an essential process that affects the evolution of the proto-atmosphere.The atmospheric escape of early terrestrial planets was extremely rapid compared with the current scenarios,and the main at... Atmospheric escape is an essential process that affects the evolution of the proto-atmosphere.The atmospheric escape of early terrestrial planets was extremely rapid compared with the current scenarios,and the main atmospheric escape modes were also quite different.During the dissipation of the nebula disk,the primordial atmosphere experienced a brief but violent"boiling"escape,in which most of the primordial atmosphere was lost.After the nebula disk dissipates,hydrodynamic escape and impact erosion are the two most important mass-loss mechanisms for the proto-atmosphere.Hydrodynamic escape is a rapid atmospheric escape process caused by strong solar radiation,while impact erosion refers to the process in which small-large or giant impacts erode the proto-atmosphere.In the early solar system,there were other escape mechanisms,such as non-thermodynamic escape and Jeans escape,but it is generally believed that these mechanisms have relatively little impact.Here we systematically introduce the above-mentioned atmospheric escape mechanisms and then make some suggestions for the existing problems and future research for atmospheric escape models. 展开更多
关键词 Proto-atmosphere Primordial atmosphere "Boil-off" Hydrodynamic escape Impact erosion
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Secondary electron emission and photoemission from a negative electron affinity semiconductor with large mean escape depth of excited electrons
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作者 谢爱根 董红杰 刘亦凡 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第4期677-690,共14页
The formulae for parameters of a negative electron affinity semiconductor(NEAS)with large mean escape depth of secondary electrons A(NEASLD)are deduced.The methods for obtaining parameters such asλ,B,E_(pom)and the m... The formulae for parameters of a negative electron affinity semiconductor(NEAS)with large mean escape depth of secondary electrons A(NEASLD)are deduced.The methods for obtaining parameters such asλ,B,E_(pom)and the maximumδandδat 100.0 keV≥E_(po)≥1.0 keV of a NEASLD with the deduced formulae are presented(B is the probability that an internal secondary electron escapes into the vacuum upon reaching the emission surface of the emitter,δis the secondary electron yield,E_(po)is the incident energy of primary electrons and E_(pom)is the E_(po)corresponding to the maximumδ).The parameters obtained here are analyzed,and it can be concluded that several parameters of NEASLDs obtained by the methods presented here agree with those obtained by other authors.The relation between the secondary electron emission and photoemission from a NEAS with large mean escape depth of excited electrons is investigated,and it is concluded that the presented method of obtaining A is more accurate than that of obtaining the corresponding parameter for a NEAS with largeλ_(ph)(λ_(ph)being the mean escape depth of photoelectrons),and that the presented method of calculating B at E_(po)>10.0 keV is more widely applicable for obtaining the corresponding parameters for a NEAS with largeλ_(ph). 展开更多
关键词 negative electron affinity semiconductor secondary electron emission PHOTOEMISSION the probability secondary electron yield large mean escape depth of excited electrons
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Distribution of O^(+)and O_(2)^(+) fluxes and their escape rates in the near-Mars magnetotail:A survey of MAVEN observations
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作者 HengLe Du Xing Cao +5 位作者 BinBin Ni Song Fu Xin Ma XiaoTong Yun MinYi Long Qiong Luo 《Earth and Planetary Physics》 EI CSCD 2022年第6期536-545,共10页
Tailward ion outflows in the Martian-induced magnetotail are known to be one of the major channels for Martian atmospheric escape.On the basis of nearly 6.5 years of observations from the Mars Atmosphere and Volatile ... Tailward ion outflows in the Martian-induced magnetotail are known to be one of the major channels for Martian atmospheric escape.On the basis of nearly 6.5 years of observations from the Mars Atmosphere and Volatile EvolutioN(MAVEN)mission,we investigate the statistical distribution of tailward and Marsward fluxes of heavy ions(i.e.,O^(+),and O_(2)^(+))in the near-Mars magnetotail and explore their characteristic responses to the corotating interaction region(CIR),solar wind dynamic pressure,and local magnetic field intensity.Our results show that the tailward fluxes of oxygen ions and molecular oxygen ions in the magnetotail are significantly greater than their Marsward fluxes and that the tailward flux of molecular oxygen ions is generally larger than that of oxygen ions.Furthermore,the tailward ion flux distribution exhibits dependence on the CIR,solar wind dynamic pressure,and local magnetic field strength in a manner stronger than the Marsward ion flux distribution.According to the distribution of tailward ion fluxes,we calculate the corresponding escape rates of heavy ions and show that when the CIR occurs,the total escape rates of oxygen ions and molecular oxygen ions increase by a factor of~2 and~1.2,respectively.We also find that the escape rates of heavy ions increase with the enhancement of solar wind dynamic pressure,whereas the overall effect of the local magnetic field is relatively weak.Our study has important implications for improved understanding of the underlying mechanisms responsible for the Martian atmospheric escape and the evolution of the Martian atmospheric climate. 展开更多
关键词 Martian-induced magnetotail atmospheric heavy ion outflow corotating interaction region escape rate
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Control of Deuteron Ions to Escape from the Magnetic Mirror Bottle by a Perpendicular Supplemental Mirror
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作者 Mitsuaki Nagata 《Journal of Modern Physics》 2019年第11期1394-1400,共7页
We have inquired into a means to decrease the number of charged particles escaping from a loss cone of a magnetic mirror reactor as many as possible. We previously reported the way of installing a supplemental magneti... We have inquired into a means to decrease the number of charged particles escaping from a loss cone of a magnetic mirror reactor as many as possible. We previously reported the way of installing a supplemental magnetic mirror (which has a cyclotron heating space within) at the exit of a main magnetic bottle. The cyclotron heating space was set to increase a reflection-efficiency of the supplemental mirror. We could not suppress the loss of the escaping deuteron ions sufficiently even with a very long mirror and a very powerful electric field. Then, in this work we propose a new plan of installing another supplemental mirror besides the previous supplemental mirror. A new mirror is set perpendicularly to the center axis of the main bottle. By the addition of the perpendicular mirror, an efficiency of sending back of escaping deuteron ions is considerably theoretically improved. Also in the previous work, since we did not touch how to supply a high-frequency electric field to the cyclotron heating space, here we consider supplying it by an extraordinary-wave with a cyclotron frequency. It is mentioned that propagation of an extraordinary-wave with an electron cyclotron frequency depends on a magnetic field strength and density of escaping electrons. 展开更多
关键词 Magnetic MIRROR Reactor CONTROL of Escaping DEUTERON IONS Electron and DEUTERON Ion Heating by Extraordinary Waves
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