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Paradoxes in Isabel Archer's View of Freedom in The Portrait of a Lady
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作者 李良彦 《海外英语》 2011年第8X期304-305,共2页
In The Portrait of a Lady, Isabel Archer values her liberty higher than a sense of security that might be guaranteed by possessing great fortune. But there are some paradoxes in Isabel Archer's view of freedom, wh... In The Portrait of a Lady, Isabel Archer values her liberty higher than a sense of security that might be guaranteed by possessing great fortune. But there are some paradoxes in Isabel Archer's view of freedom, which have caused her failure in the fulfillment of her view of freedom. 展开更多
关键词 paradoxes VIEW FREEDOM QUEST FEAR
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A helium stratified and ingassed lower mantle: resolving the helium paradoxes
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作者 Honggang Zhu Xuefang Li Yingkui Xu 《Acta Geochimica》 EI CAS CSCD 2020年第1期4-10,共7页
It is generally believed a variation of 3He/4He isotopic ratios in the mantle is due to only the decay of U and Th,which produces4 He as well as heat.Here we show that not only3He/4He isotopic ratios but also helium c... It is generally believed a variation of 3He/4He isotopic ratios in the mantle is due to only the decay of U and Th,which produces4 He as well as heat.Here we show that not only3He/4He isotopic ratios but also helium contents can be fractionated by thermal diffusion in the lower mantle.The driving force for that fractionation is the adiabatic or convective temperature gradient,which always produces elemental and isotopic fractionation along temperature gradient by thermal diffusion with higher light/heavy isotopic ratio in the hot end.Our theoretical model and calculations indicate that the lower mantle is helium stratified,caused by thermal diffusion due to*400℃temperature contrast across the lower mantle.The highest3He/4He isotopic ratios and lowest He contents are in the lowermost mantle,which is a consequence of thermaldiffusion fractionation rather than the lower mantle is a primordial and undegassed reservoir.Therefore,oceanicisland basalts derived from the deepest lower mantle with high3He/4He isotopic ratios and less He contents—the long-standing helium paradox,is solved by our model.Because vigorous convection in the upper mantle had resulted in disordered or disorganized thermal-diffusion effects in He,Mid-ocean ridge basalts unaffected by mantle plume have a relatively homogenous and lower!3He/4He isotopic compositions.Our model also predicts that 3He/4He isotopic ratios in the deepest lower mantle of early Earth could be even higher than that of Jupiter,the initial He isotopic ratio in our solar system,because the temperature contrast across the lower mantle in the early Earth is the largest and less4 He had been produced by the decay of U and Th.Moreover,the early helium-stratified lower mantle owned the lowest He contents due to over-degassing caused by the largest temperature contrast.Consequently,succeeding evolution of the lower mantle is a He ingassed process due to secular cooling of the deepest mantle.This explains why significant amount of He produced by the decay of U and Th in the lower mantle were not released,another long-standing heat–helium paradox. 展开更多
关键词 Helium paradox Thermal diffusion Mantle convection Adiabatic temperature gradient Primordial mantle Ingassed lower mantle
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Space-Time Diagrams Lead to False Paradoxes
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作者 Robert L. Shuler 《Journal of Applied Mathematics and Physics》 2022年第12期3804-3813,共10页
This paper provides a clear analysis of how hypothetical concepts not allowed in Special Relativity should be treated and exposes hidden assumptions in space-time diagrams used on YouTube, where some prominent physici... This paper provides a clear analysis of how hypothetical concepts not allowed in Special Relativity should be treated and exposes hidden assumptions in space-time diagrams used on YouTube, where some prominent physicists have taken to publishing on popular topics that may not survive peer review. Such casual graphical treatment conceals the fact that space-time diagrams provide only for the Einstein synchronization convention for all observers, not the many other valid synchronization protocols, and also obscure that relativity’s equality of reference frames is rebutted if concepts outside relativity, such as instant communication, are introduced. These omissions of unconscious assumptions have been used to “prove” the existence of block time and time travel or time paradoxes. We will show the contradictory assumptions amount to assuming time travel, rather than the more mundane need to adjust synchronization conventions. We further show a new result that the use of the space-time diagrams as proposed by these “explainers” leads to discontinuities in which a differential change in communication speed leads to a sudden jump from present to long-past arrival time, strongly suggesting invalidity of the method. 展开更多
关键词 SPACE-TIME Block Time Block Universe Special Relativity Faster Than Light FTL Causality Violation Time Paradox SIMULTANEITY
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Dynamic foraging strategy adaptation to heterogeneous environments contributes to social aggregation in snub-nosed monkeys
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作者 Lan Zhao Sheng-Nan Ji +7 位作者 Xiao-Bing Du Jia-Hui Liu Bo-Lun Zhang Pei-Hua Li Yi-Jun Yang Bao-Guo Li Yan-Qing Guo Xiao-Guang Qi 《Zoological Research》 SCIE CSCD 2024年第1期39-54,共16页
The dynamics of animal social structures are heavily influenced by environmental patterns of competition and cooperation.In folivorous colobine primates,prevailing theories suggest that larger group sizes should be fa... The dynamics of animal social structures are heavily influenced by environmental patterns of competition and cooperation.In folivorous colobine primates,prevailing theories suggest that larger group sizes should be favored in rainforests with a year-round abundance of food,thereby reducing feeding competition.Yet,paradoxically,larger groups are frequently found in high-altitude or high-latitude montane ecosystems characterized by a seasonal scarcity of leaves.This contradiction is posited to arise from cooperative benefits in heterogeneous environments.To investigate this hypothesis,we carried out a six-year field study on two neighboring groups of golden snub-nosed monkey(Rhinopithecus roxellana),a species representing the northernmost distribution of colobine primates.Results showed that the groups adjusted their movement and habitat selection in response to fluctuating climates and spatiotemporal variability of resources,indicative of a dynamic foraging strategy.Notably,during the cold,resource-scarce conditions in winter,the large group occupied food-rich habitats but did not exhibit significantly longer daily travel distances than the smaller neighboring group.Subsequently,we compiled an eco-behavioral dataset of 52 colobine species to explore their evolutionary trajectories.Analysis of this dataset suggested that the increase in group size may have evolved via home range expansion in response to the cold and heterogeneous climates found at higher altitudes or latitudes.Hence,we developed a multi-benefits framework to interpret the formation of larger groups by integrating environmental heterogeneity.In cold and diverse environments,even smaller groups require larger home ranges to meet their dynamic survival needs.The spatiotemporal distribution of high-quality resources within these expanded home ranges facilitates more frequent interactions between groups,thereby encouraging social aggregation into larger groups.This process enhances the benefits of collaborative actions and reproductive opportunities,while simultaneously optimizing travel costs through a dynamic foraging strategy. 展开更多
关键词 Social evolution Folivore paradox MLS Rhinopithecus roxellana Multi-benefits framework
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Paradoxical herniation associated with hyperbaric oxygen therapy after decompressive craniectomy: A case report
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作者 Zhong-Xing Ye Xin-Xin Fu +6 位作者 Yang-Zong Wu Ling Lin Liang-Qi Xie Yu-Ling Hu Yi Zhou Zhu-Gui You Hai Lin 《World Journal of Clinical Cases》 SCIE 2024年第10期1793-1798,共6页
BACKGROUND Whether hyperbaric oxygen therapy(HBOT)can cause paradoxical herniation is still unclear.CASE SUMMARY A 65-year-old patient who was comatose due to brain trauma underwent decompressive craniotomy and gradua... BACKGROUND Whether hyperbaric oxygen therapy(HBOT)can cause paradoxical herniation is still unclear.CASE SUMMARY A 65-year-old patient who was comatose due to brain trauma underwent decompressive craniotomy and gradually regained consciousness after surgery.HBOT was administered 22 d after surgery due to speech impairment.Paradoxical herniation appeared on the second day after treatment,and the patient’s condition worsened after receiving mannitol treatment at the rehabilitation hospital.After timely skull repair,the paradoxical herniation was resolved,and the patient regained consciousness and had a good recovery as observed at the follow-up visit.CONCLUSION Paradoxical herniation is rare and may be caused by HBOT.However,the underlying mechanism is unknown,and the understanding of this phenomenon is insufficient.The use of mannitol may worsen this condition.Timely skull repair can treat paradoxical herniation and prevent serious complications. 展开更多
关键词 Decompressive craniectomy Hyperbaric oxygen therapy MANNITOL Paradoxical herniation Case report
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Multiple paradoxical embolisms caused by central venous catheter thrombus passing through a patent foramen ovale: A case report
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作者 Jian-Duan Li Nian Xu +2 位作者 Qiang Zhao Biao Li Li Li 《World Journal of Clinical Cases》 SCIE 2024年第4期842-846,共5页
BACKGROUND To date,this is the first case of a paradoxical embolism(PDE)that concurrently manifested in the coronary and lower limb arteries and was secondary to a central venous catheter(CVC)thrombus via a patent for... BACKGROUND To date,this is the first case of a paradoxical embolism(PDE)that concurrently manifested in the coronary and lower limb arteries and was secondary to a central venous catheter(CVC)thrombus via a patent foramen ovale(PFO).CASE SUMMARY Here,we report a case of simultaneous coronary and lower limb artery embolism in a PFO patient carrier of a CVC.The patient presented to the hospital with acute chest pain and lower limb fatigue.Doppler ultrasound showed a large thrombus in the right internal jugular vein,precisely at the tip of the CVC.Transthoracic and transesophageal echocardiography confirmed the existence of a PFO,with inducible right-to-left shunting by the Valsalva maneuver.The patient was administered an extended course of anticoagulation therapy,and then the CVC was successfully removed.Percutaneous PFO closure was not undertaken.There was no recurrence during follow-up.CONCLUSION Thus,CVC-associated thrombosis is a potential source for multiple PDE in PFO patients. 展开更多
关键词 Paradoxical embolism Central venous catheter Patent foramen ovale Acute myocardial infarction Case report
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COVID-19 mortality paradox(United States vs Africa):Mass vaccination vs early treatment
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作者 Mina Thabet Kelleni 《World Journal of Experimental Medicine》 2024年第1期6-12,共7页
The coronavirus disease 2019(COVID-19)mortality rate in 55 African countries is almost 4.5 times lower than in the coronavirus disease 2019(COVID-19)despite Africa having over 4.2 times more people.This mortality para... The coronavirus disease 2019(COVID-19)mortality rate in 55 African countries is almost 4.5 times lower than in the coronavirus disease 2019(COVID-19)despite Africa having over 4.2 times more people.This mortality paradox is also evident when comparing Nigeria,a heavily populated,poorly vaccinated and weakly mandated country to Israel,a small,highly vaccinated and strictly mandated country.Nigeria has almost 4 times lower COVID mortality than Israel.In this Field of Vision perspective,I explain how this paradox has evolved drawing upon my academic,clinical and social experience.Since April 2020,I’ve developed and been using the Egyptian immune-modulatory Kelleni’s protocol to manage COVID-19 patients including pediatric,geriatric,pregnant,immune-compromised and other individuals suffering from multiple comorbidities.It’s unfortunate that severe acute respiratory syndrome coronavirus 2 is still evolving accompanied by more deaths.However in Africa,we’ve been able to live without anxiety or mandates throughout the pandemic because we trust science and adopted early treatment using safe,and effective repurposed drugs that have saved the majority of COVID-19 patients.This article represents an African and Egyptian tale of honor. 展开更多
关键词 COVID-19 Early treatment Kelleni’s Protocol Mandates Mortality Paradox SARS-CoV-2 Nucleic acid based vaccines
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Solving the Olbers’s Paradox, Explaining the “Red-Shift”, and Challenging the Relativities by “Sun Matters Theory” and “Sun Model of Universe”, an Evolution of the Einstein’s Static Universe Model
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作者 Wanpeng Sun 《Natural Science》 2024年第2期7-18,共12页
Olbers’s paradox, known as the dark night paradox, is an argument in astrophysics that the darkness of the night sky conflicts with the assumption of an infinite and eternal static universe. Big-Bang theory was used ... Olbers’s paradox, known as the dark night paradox, is an argument in astrophysics that the darkness of the night sky conflicts with the assumption of an infinite and eternal static universe. Big-Bang theory was used to partially explain this paradox, while introducing new problems. Hereby, we propose a better theory, named Sun Matters Theory, to explain this paradox. Moreover, this unique theory supports and extended the Einstein’s static universe model proposed by Albert Einstein in 1917. Further, we proposed our new universe model, “Sun Model of Universe”. Based on the new model and novel theory, we generated innovative field equation by upgrading Einstein’s Field Equation through adding back the cosmological constant, introducing a new variable and modifying the gravitationally-related concepts. According to the Sun Model of Universe, the dark matter and dark energy comprise the so-called “Sun Matters”. The observed phenomenon like the red shift is explained as due to the interaction of ordinary light with Sun Matters leading to its energy and frequency decrease. In Sun Model, our big universe consists of many universes with ordinary matter at the core mixed and surrounded with the Sun Matters. In those universes, the laws of physics may be completely or partially different from that of our ordinary universe with parallel civilizations. The darkness of night can be easily explained as resulting from the interaction of light with the Sun Matters leading to the sharp decrease in the light intensity. Sun Matters also scatter the light from a star, which makes it shining as observed by Hubble. Further, there is a kind of Sun Matters named “Sun Waters”, surrounding every starts. When lights pass by the sun, the Sun Waters deflect the lights to bend the light path. According to the Sun Model, it is the light bent not the space bent that was proposed in the theory of relativities. 展开更多
关键词 Olbers’s Paradox Sun Matters Theory Sun Model of Universe Einstein’s Universe Dark Mass
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Earth: Review Article
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作者 Vladimir S. Netchitailo 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第1期31-51,共21页
Every year on 22 April, we have celebrated Earth Day and the beautiful planet we call home. Earth Day, established in 1970, has been used to highlight our planet’s environmental challenges and raise awareness of the ... Every year on 22 April, we have celebrated Earth Day and the beautiful planet we call home. Earth Day, established in 1970, has been used to highlight our planet’s environmental challenges and raise awareness of the importance of protecting our world for future generations [1]. To provide the protection of our planet, we should explain Earth’s environmental challenges to the best of our knowledge in frames of contemporary Geophysics. This paper gives a short overview of the developed Hypersphere World-Universe Model (WUM) and pay particular attention to the principal role of Dark Matter (DM) in the Earth’s life. In this manuscript, we discuss different aspects of the Earth: a condition of Young Earth before the Beginning of life on It;Internal Structure;“The 660-km Boundary” that we named Geomagma;Random Variations of Earth’s Rotational Speed on a daily basis;Origin of Moon;Expanding Earth;Internal Heating;Faint Young Sun paradox;Geocorona and Planetary Coronas;High-Energy Atmospheric Physics. WUM proposed principally different ways to solve the problems of Internal Heating, Origin of the Moon, and Faint Young Sun paradox based on DM core of the Earth. The Model revealed the fact that the Sun Activity causes the Geomagma Activity and, as a consequence, Random Variations of Earth’s Rotational Speed by the varying Sun’s magnetic field. 展开更多
关键词 Internal Structure 660-km Boundary Internal Heating Faint Young Sun Paradox Origin of Moon Expanding Earth Random Variations of Earth’s Rotational Speed
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物理学咬文嚼字之四十六 Oh,Paradoxes
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作者 曹则贤 《物理》 CAS 北大核心 2012年第5期332-336,共5页
Paradox在中文物理学文献中被翻译成悖论或者佯谬,武断了点,不足以传达paradox的真实含义.Paradox一直伴随着人类的认识进程,芝诺佯谬、孪生子佯谬、EPR佯谬、理发师佯谬等是数学和物理绕不开的话题.与paradox意义相近的词有dilemma,ant... Paradox在中文物理学文献中被翻译成悖论或者佯谬,武断了点,不足以传达paradox的真实含义.Paradox一直伴随着人类的认识进程,芝诺佯谬、孪生子佯谬、EPR佯谬、理发师佯谬等是数学和物理绕不开的话题.与paradox意义相近的词有dilemma,antinomy和catch-22等. 展开更多
关键词 物理学 PARADOX PARADOX 孪生子佯谬 EPR佯谬 认识进程 悖论 伴随
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Paradoxes in the Textual Development of the Laozi: A Closer Examination of Chapters Eight and Twenty-Four
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作者 CUI Xiaojiao 《Frontiers of Philosophy in China》 2017年第3期393-407,共15页
In light of the recently published Western Han period bamboo-slip Laozi, now in the collection of Peking University, this paper explores several paradoxes in the textual development of the Laozi. Specifically, it pres... In light of the recently published Western Han period bamboo-slip Laozi, now in the collection of Peking University, this paper explores several paradoxes in the textual development of the Laozi. Specifically, it presents two examples suggesting that since the wording in the Laozi was originally intended to be ambiguous and paradoxical, during the transmission of the text, the compilers or commentators modified some of the paradoxes to make better sense. Eventually those modifications came to replace the original text. In the first part of this article examines certain contrasting differences in Chapter Eight from the Beida Laozi, the Mawangdui Laozi, and the received Laozi. The second part, I examine certain other contrasting differences from these same versions from Chapter Twenty-Four are discussed. This paper argues that these differences among the various versions are not the product of transcribal error; rather, they are the result of compilers or commentators who revised these passages against their earliest versions in order to make the meaning clearer and more explicit. 展开更多
关键词 Beida Laozi Mawangdui Laozi received Laozi paradoxes
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Twin Paradox and Proper Time
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作者 Donald Lem 《Journal of Applied Mathematics and Physics》 2024年第1期12-15,共4页
Professors Mohazzbi and Luo [1] published “Despite several attempts have been made to explain the twin paradox … none of the explanations … resolved the paradox. If the paradox can be ever resolved, it requires a m... Professors Mohazzbi and Luo [1] published “Despite several attempts have been made to explain the twin paradox … none of the explanations … resolved the paradox. If the paradox can be ever resolved, it requires a much deeper understanding … of the theory of relativity”. The deeper understanding of resolving the paradox is by applying more explicit definitions of proper time interval, Lorentz transform, time dilation, and aging time. 展开更多
关键词 Twin Paradox Proper Time Minkowski Metric Schwarzschild Metric
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Writers' Paradoxes
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作者 林日 《当代外语研究》 2004年第12期2-2,共1页
The supreme triumph of reason is to cast doubt upon ixs own validity.--Miguel de Unamuno理智的最大胜利在于对其自身的正确性提出了怀疑。米格尔·德·乌纳穆诺(1864-1936,西班牙教育家,哲学家及作家)Boredom-the desire... The supreme triumph of reason is to cast doubt upon ixs own validity.--Miguel de Unamuno理智的最大胜利在于对其自身的正确性提出了怀疑。米格尔·德·乌纳穆诺(1864-1936,西班牙教育家,哲学家及作家)Boredom-the desire for desires. --Leo Tolstoy厌烦--寻求欲望的欲望。列·托尔斯泰(1828-1910,俄国作家,思想家)The only way to get rid of a temptation is to yield to it.--Oscar 展开更多
关键词 paradoxes WRITERS
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Living Paradoxes
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作者 林日 《当代外语研究》 2005年第7期2-2,共1页
InLeningrad,freezingpointiscalledmeltingpoint.在列宁格勒冰点被称之为融点。Howcanyoutellthedancefromthedancer?你怎么可能把舞蹈和舞蹈者区分开来呢?Ifyouturnonthelightquicklyenoughyoucanseewhatthedarklookslike.如果你开灯... InLeningrad,freezingpointiscalledmeltingpoint.在列宁格勒冰点被称之为融点。Howcanyoutellthedancefromthedancer?你怎么可能把舞蹈和舞蹈者区分开来呢?Ifyouturnonthelightquicklyenoughyoucanseewhatthedarklookslike.如果你开灯的速度足够快的话,那你就能看见黑暗是什么样子的。 展开更多
关键词 Living paradoxes
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ON AVOIDING ASSOCIATION PARADOXES INCONTINGENCY TABLES
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作者 DONG Jianping(Department of Mathematical Sciences, Michigan Technological University,Houghton, MI 49931, U.S.A.) 《Systems Science and Mathematical Sciences》 SCIE EI CSCD 1998年第3期272-279,共8页
This article is concerned with paradoxes in 2×2×n contingency tables, suchas Simpson’s paradox, in which the association in the 2 × 2 marginal table is quite different from the associations in the 2 &#... This article is concerned with paradoxes in 2×2×n contingency tables, suchas Simpson’s paradox, in which the association in the 2 × 2 marginal table is quite different from the associations in the 2 × 2 partial tables. We prove that if the relative number of observations in each row of each partial table or in each column of each partial table is constant, then Simpson’s paradox cannot occur. We also prove that under a certain condition, the paradox cannot occur if the odds ratios in the partial tables are uniformly greater than a lower bound (e.g. > 1.125) or uniformly less than some upper bound.Finally, we show that Simpson’s paradox and an amalgamation paradox cannot occur if certain ratios of cell counts are constant in the partial tables. 展开更多
关键词 CATEGORICAL data Simpson’s PARADOX odds RATIO RELATIVE risk COLLAPSIBILITY
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Paradoxical roles of inhibitory autapse and excitatory synapse in formation of counterintuitive anticipated synchronization
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作者 丁学利 古华光 +1 位作者 李玉叶 贾雁兵 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第8期499-509,共11页
Different from the common delayed synchronization(DS)in which response appears after stimulation,anticipated synchronization(AS)in unidirectionally coupled neurons denotes a counterintuitive phenomenon in which respon... Different from the common delayed synchronization(DS)in which response appears after stimulation,anticipated synchronization(AS)in unidirectionally coupled neurons denotes a counterintuitive phenomenon in which response of the receiver neuron appears before stimulation of the sender neuron,showing an interesting function of brain to anticipate the future.The dynamical mechanism for the AS remains unclear due to complex dynamics of inhibitory and excitatory modulations.In this article,the paradoxical roles of excitatory synapse and inhibitory autapse in the formation of AS are acquired.Firstly,in addition to the common roles such that inhibitory modulation delays and excitatory modulation advances spike,paradoxical roles of excitatory stimulation to delay spike via type-II phase response and of inhibitory autapse to advance spike are obtained in suitable parameter regions,extending the dynamics and functions of the excitatory and inhibitory modulations.Secondly,AS is related to the paradoxical roles of the excitatory and inhibitory modulations,presenting deep understandings to the AS.Inhibitory autapse induces spike of the receiver neuron advanced to appear before that of the sender neuron at first,and then excitatory synapse plays a delay role to prevent the spike further advanced,resulting in the AS as the advance and delay effects realize a dynamic balance.Lastly,inhibitory autapse with strong advance,middle advance,and weak advance and delay effects induce phase drift(spike of the receiver neuron advances continuously),AS,and DS,respectively,presenting comprehensive relationships between AS and other behaviors.The results present potential measures to modulate AS related to brain function. 展开更多
关键词 anticipated synchronization inhibitory autapse excitatory synapse paradoxical firing
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Characteristics of vertical distributions of methane and dimethylsulphoniopropionate in the southern Yap Trench
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作者 Yuhuan HUANG Chengjun SUN +4 位作者 Lina Lü Neal Xiangyu DING Liangmin YU Guipeng YANG Haibing DING 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第6期2101-2116,共16页
Methane(CH_(4) )and dimethylsulphoniopropionate(DMSP)are major carbon and sulfur sources for bacterioplankton in the ocean.We investigated the characteristics of CH_(4) and DMSP in the southern Yap Trench from sea sur... Methane(CH_(4) )and dimethylsulphoniopropionate(DMSP)are major carbon and sulfur sources for bacterioplankton in the ocean.We investigated the characteristics of CH_(4) and DMSP in the southern Yap Trench from sea surface to hadal zone in June 2017.We found that concentrations of CH_(4) varied from 1.5 to 4.5 nmol/L with saturation between 94% and 204% in the euphotic layer.Concentrations of dissolved DMSP(DMSPd)ranged from 0.5 to 3.7 nmol/L with higher values in surface water and decreased with depth.Concentrations of particulate DMSP(DMSPp)varied from 0 to 13.6 nmol/L.Concentrations of total DMSP(DMSPt)ranged 2.0-15.2 nmol/L.Their concentrations decreased slightly and reached consistent levels in 200-3000-m depth due probably to heterotrophic bacterial production in marine aphotic and high-pressure environments.An exception occurred around 4000-m depth where their concentrations increased considerably and then decreased in deeper water.This previously unrecognized phenomenon sheds light on the elevated concentrations of DMSP in the abyssal layer that might be affected by the Lower Circumpolar Deep Water(LCPW).Concentrations of CH_(4) in seawater of the Benthic Boundary Layer of the southern Yap Trench were slightly higher than those in the water column at approximate depth,and concentrations of DMSP in seawater of the Benthic Boundary Layer of the southern Yap Trench were not much higher than those in the water column at the approximate depth,indicating that sediment was a weak source of CH_(4) but was not a source of DMSP for seawater in the study area.This study presented clear correlations between CH_(4) and DMSP from sea surface to sea bottom,proving that DMSP might be a potential substrate for CH_(4) not only in oxic surface seawater but also in deep water. 展开更多
关键词 METHANE dimethylsulphoniopropionate(DMSP) hadal zone Jiaolong submersible Yap Trench oceanic methane paradox
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Coral reef ecological pump for gathering and retaining nutrients and exporting carbon:a review and perspectives
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作者 Linbin Zhou Yehui Tan Liangmin Huang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第6期1-15,共15页
How coral reefs with high productivity and biodiversity can flourish in oligotrophic tropical oceans has inspired substantial research on coral reef ecosystems.Increasing evidence shows that similar to water in an oas... How coral reefs with high productivity and biodiversity can flourish in oligotrophic tropical oceans has inspired substantial research on coral reef ecosystems.Increasing evidence shows that similar to water in an oasis in the desert,there are stable nutrient supplies to coral reefs in oligotrophic oceans.Here,with emphasis on the fluxes of organic matter,we summarize at the ecosystem level(1)the multiple input pathways of external nutrients,(2)the storage of nutrients in reef organisms,(3)the efficient retaining and recycling of dissolved and particulate organic matter within coral reef ecosystems,(4)the distinctly high phytoplankton productivity and biomass inside and near oceanic coral reefs,and(5)the export of reef-related organic carbon to adjacent open oceans.These properties enable coral reefs to function as ecological“pumps”for gathering nutrients across ecosystems and space,retaining and recycling nutrients within the ecosystem,supporting high phytoplankton productivity,and exporting organic carbon to adjacent open oceans.Particularly,the high phytoplankton productivity and biomass make waters around coral reefs potential hotspots of carbon export to ocean depths via the biological pump.We demonstrate that organic carbon influx is vital for coral reef ecosystems’carbon budget and carbon export.The concept of the coral reef ecological pump provides a framework to improve the understanding of the functioning of the coral reef ecosystem and its responses to disturbance.Prospects of the coral reef ecological pump in coral reef studies are discussed in changing oceans driven by human activities and global change in the Anthropocene. 展开更多
关键词 Darwin’s Paradox coral reef NUTRIENTS coral reef ecological pump carbon export ocean carbon cycle
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Paradoxical vocal fold motion masquerading as post-anesthetic respiratory distress:A case report
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作者 Jongyoon Baek Dae-Lim Jee +2 位作者 Yoon Seok Choi Sang Woo Kim Eun Kyung Choi 《World Journal of Clinical Cases》 SCIE 2023年第10期2349-2354,共6页
BACKGROUND Functional vocal cord disorders can be a differential diagnosis for postoperative upper airway obstruction requiring urgent intervention.However,this may be unfamiliar to anesthesiologists who would favor i... BACKGROUND Functional vocal cord disorders can be a differential diagnosis for postoperative upper airway obstruction requiring urgent intervention.However,this may be unfamiliar to anesthesiologists who would favor inappropriate airway intervention and increased morbidity.CASE SUMMARY A 61-year-old woman underwent cervical laminectomy,followed by laparoscopic cholecystectomy 10 mo later.Despite adequate reversal of neuromuscular blockade,the patient experienced repetitive respiratory difficulty with inspiratory stridor after extubation.After the second operation,the patient was diagnosed with paradoxical vocal fold motion(PVFM)by an otolaryngologist based on the clinical features and fiberoptic bronchoscopy results,and the patient was successfully treated.CONCLUSION PVFM should be considered a differential diagnosis if a patient presents with stridor after general anesthesia. 展开更多
关键词 ANESTHESIOLOGY Vocal fold Paradoxical motion Postoperative respiratory distress Case report
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Transient ischemic attack induced by pulmonary arteriovenous fistula in a child:A case report
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作者 Jun Zheng Qi-Yue Wu +1 位作者 Xia Zeng Du-Fei Zhang 《World Journal of Clinical Cases》 SCIE 2023年第9期2009-2014,共6页
BACKGROUND Cerebral ischemic stroke is attributed to paradoxical cerebral embolism.Pulmonary arteriovenous fistula(PAVF)is a rare potential cause of cerebral ischemic stroke,and cerebral ischemic stroke induced by PAV... BACKGROUND Cerebral ischemic stroke is attributed to paradoxical cerebral embolism.Pulmonary arteriovenous fistula(PAVF)is a rare potential cause of cerebral ischemic stroke,and cerebral ischemic stroke induced by PAVF in children is rare.CASE SUMMARY We report a case of right PAVF that presented as a transient ischemic attack(TIA)in a 13-year-old boy.The patient underwent embolization therapy and remained clinically stable for 2 years after treatment.CONCLUSION TIA induced by PAVF in children is rare,lacks typical clinical manifestations,and should not be ignored. 展开更多
关键词 Pulmonary arteriovenous fistula Transient ischemic attack Paradoxical cerebral embolism CHILDREN Case report
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