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Investigations for the assessment of adult patients presenting to the emergency department with supraventricular tachycardia 预览
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作者 Harith Fernando Nicholas Adams Biswadev Mitra 《世界急诊医学杂志(英文)》 CAS CSCD 2020年第1期54-59,共6页
Dear editor,Patients with supraventricular tachycardia(SVT)commonly present to the emergency department(ED).Current guidelines[1,2]do not recommend routine pathology testing and a report on the topic has questioned th... Dear editor,Patients with supraventricular tachycardia(SVT)commonly present to the emergency department(ED).Current guidelines[1,2]do not recommend routine pathology testing and a report on the topic has questioned their role.A systematic review concluded that troponin testing is commonly performed with a high proportion of positive fi ndings,but these results were not associated with major adverse cardiac events.[3]The conclusions of this review were limited by paucity of data and heterogeneity among studies. 展开更多
关键词 TACHYCARDIA ROUTINE PATHOLOGY
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Dense matter with eXTP
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作者 Anna L. Watts WenFei Yu +73 位作者 Juri Poutanen Shu Zhang Sudip Bhattacharyya Slavko Bogdanov Long Ji Alessandro Patruno Thomas E. Riley Pavel Bakala Altan Baykal Federico Bernardini Ignazio Bombaci Edward Brown Yuri Cavecchi Deepto Chakrabarty Jérome Chenevez Nathalie Degenaar Melania Del Santo Tiziana Di Salvo Victor Doroshenko Maurizio Falanga Robert D. Ferdman Marco Feroci Angelo F. Gambino MingYu Ge Svenja K. Greif Sebastien Guillot Can Gungor Dieter H. Hartmann Kai Hebeler Alexander Heger Jeroen Homan Rosario Iaria Jean in 't Zand Oleg Kargaltsev Aleksi Kurkela XiaoYu Lai Ang Li XiangDong Li ZhaoSheng Li Manuel Linares FangJun Lu Simin Mahmoodifar Mariano Méndez M. Coleman Miller Sharon Morsink Joonas Nattila Andrea Possenti Chanda Prescod-Weinstein JinLu Qu Alessandro Riggio Tuomo Salmi Andrea Sanna Andrea Santangelo Hendrik Schatz Achim Schwenk LiMing Song Eva v Srámková Benjamin Stappers Holger Stiele Tod Strohmayer Ingo Tews Laura Tolos Gabriel Torok David Tsang Martin Urbanec Andrea Vacchi RenXin Xu YuPeng Xu Silvia Zane GuoBao Zhang ShuangNan Zhang WenDa Zhang ShiJie Zheng Xia Zhou 《中国科学:物理学、力学、天文学英文版》 SCIE EI CAS CSCD 2019年第2期28-44,共17页
In this White Paper we present the potential of the Enhanced X-ray Timing and Polarimetry (eXTP) mission for determining the nature of dense matter;neutron star cores host an extreme density regime which cannot be rep... In this White Paper we present the potential of the Enhanced X-ray Timing and Polarimetry (eXTP) mission for determining the nature of dense matter;neutron star cores host an extreme density regime which cannot be replicated in a terrestrial laboratory. The tightest statistical constraints on the dense matter equation of state will come from pulse profile modelling of accretion-powered pulsars, burst oscillation sources, and rotation-powered pulsars. Additional constraints will derive from spin measurements, burst spectra, and properties of the accretion flows in the vicinity of the neutron star. Under development by an international Consortium led by the Institute of High Energy Physics of theChinese Academy of Sciences, the eXTP mission is expected to be launched in the mid 2020s. 展开更多
关键词 NEUTRON X-rays DENSE MATTER EQUATION of STATE
Accretion in strong field gravity with eXTP
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作者 Alessandra De Rosa Phil Uttley +99 位作者 LiJun Gou Yuan Liu Cosimo Bambi Didier Barret Tomaso Belloni Emanuele Berti Stefano Bianchi Ilaria Caiazzo Piergiorgio Casella Marco Feroci Valeria Ferrari Leonardo Gualtieri Jeremy Heyl Adam Ingram Vladimir Karas FangJun Lu Bin Luo Giorgio Matt Sara Motta Joseph Neilsen Paolo Pani Andrea Santangelo XinWen Shu JunFeng Wang Jian-Min Wang YongQuan Xue YuPeng Xu WeiMin Yuan YeFei Yuan Shuang-Nan Zhang Shu Zhang Ivan Agudo Lorenzo Amati Nils Andersson Cristina Baglio Pavel Bakala Altan Baykal Sudip Bhattacharyya Ignazio Bombaci Niccoló Bucciantini Fiamma Capitanio Riccardo Ciolfi Wei K. Cui Filippo D'Ammando Thomas Dauser Melania Del Santo Barbara De Marco Tiziana Di Salvo Chris Done Michal Dovvciak Andrew C. Fabian Maurizio Falanga Angelo Francesco Gambino Bruce Gendre Victoria Grinberg Alexander Heger Jeroen Homan Rosario Iaria JiaChen Jiang ChiChuan Jin Elmar Koerding Manu Linares Zhu Liu Thomas J. Maccarone Julien Malzac Antonios Manousakis Frédéric Marin Andrea Marinucci Missagh Mehdipour Mariano Méndez Simone Migliari Cole Miller Giovanni Miniutti Emanuele Nardini Paul T. O'Brien Julian P. Osborne Pierre Olivier Petrucci Andrea Possenti Alessandro Riggio Jerome Rodriguez Andrea Sanna LiJing Shao Malgosia Sobolewska Eva Sramkova Abigail L. Stevens Holger Stiele Giulia Stratta Zdenek Stuchlik Jiri Svoboda Fabrizio Tamburini Thomas M. Tauris Francesco Tombesi Gabriel Torok Martin Urbanec Frederic Vincent QingWen Wu Feng Yuan Jean J. M. in 't Zand Andrzej A. Zdziarski XinLin Zhou 《中国科学:物理学、力学、天文学英文版》 SCIE EI CAS CSCD 2019年第2期45-73,共29页
In this paper we describe the potential of the enhanced X-ray Timing and Polarimetry (eXTP) mission for studies related to accretion flows in the strong field gravity regime around both stellar-mass and supermassive b... In this paper we describe the potential of the enhanced X-ray Timing and Polarimetry (eXTP) mission for studies related to accretion flows in the strong field gravity regime around both stellar-mass and supermassive black-holes. eXTP has the unique capability of using advanced “spectral-timing-polarimetry” techniques to analyze the rapid variations with three orthogonal diagnostics of the flow and its geometry, yielding unprecedented insight into the inner accreting regions, the effects of strong field gravity on the material within them and the powerful outflows which are driven by the accretion process. 展开更多
关键词 X-RAY BLACK HOLES PHYSICS ACCRETION
Observatory science with eXTP
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作者 Jean J. M. in 't Zand Enrico Bozzo +103 位作者 JinLu Qu Xiang-Dong Li Lorenzo Amati Yang Chen Immacolata Donnarumma Victor Doroshenko Stephen A. Drake Margarita Hernanz Peter A. Jenke Thomas J. Maccarone Simin Mahmoodifar Domitilla de Martino Alessandra De Rosa Elena M. Rossi Antonia Rowlinson Gloria Sala Giulia Stratta Thomas M. Tauris Joern Wilms XueFeng Wu Ping Zhou Iván Agudo Diego Altamirano Jean-Luc Atteia Nils A. Andersson M. Cristina Baglio David R. Ballantyne Altan Baykal Ehud Behar Tomaso Belloni Sudip Bhattacharyya Stefano Bianchi Anna Bilous Pere Blay Jo ao Braga S?ren Brandt Edward F. Brown Niccolò Bucciantini Luciano Burderi Edward M. Cackett Riccardo Campana Sergio Campana Piergiorgio Casella Yuri Cavecchi Frank Chambers Liang Chen Yu-Peng Chen Jérome Chenevez Maria Chernyakova ChiChuan Jin Riccardo Ciolfi Elisa Costantini Andrew Cumming Antonino D'Aì Zi-Gao Dai Filippo D'Ammando Massimiliano De Pasquale Nathalie Degenaar Melania Del Santo Valerio D'Elia Tiziana Di Salvo Gerry Doyle Maurizio Falanga XiLong Fan Robert D. Ferdman Marco Feroci Federico Fraschetti Duncan K. Galloway Angelo F. Gambino Poshak Gandhi MingYu Ge Bruce Gendre Ramandeep Gill Diego Gotz Christian Gouiffès Paola Grandi Jonathan Granot Manuel Güdel Alexander Heger Craig O. Heinke Jeroen Homan Rosario Iaria Kazushi Iwasawa Luca Izzo Long Ji Peter G. Jonker Jordi José Jelle S. Kaastra Emrah Kalemci Oleg Kargaltsev Nobuyuki Kawai Laurens Keek Stefanie Komossa Ingo Kreykenbohm Lucien Kuiper Devaky Kunneriath Gang Li En-Wei Liang Manuel Linares Francesco Longo FangJun Lu Alexander A. Lutovinov Denys Malyshev Julien Malza 《中国科学:物理学、力学、天文学英文版》 SCIE EI CAS CSCD 2019年第2期97-138,共42页
In this White Paper we present the potential of the enhanced X-ray Timing and Polarimetry (eXTP) mission for studies related toObservatory Science targets. These include flaring stars, supernova remnants, accreting wh... In this White Paper we present the potential of the enhanced X-ray Timing and Polarimetry (eXTP) mission for studies related toObservatory Science targets. These include flaring stars, supernova remnants, accreting white dwarfs, low and high mass X-raybinaries, radio quiet and radio loud active galactic nuclei, tidal disruption events, and gamma-ray bursts. eXTP will be excellentlysuited to study one common aspect of these objects: their often transient nature. Developed by an international Consortium ledby the Institute of High Energy Physics of the Chinese Academy of Science, the eXTP mission is expected to be launched in themid 2020s. 展开更多
关键词 space research instruments nuclear ASTROPHYSICS flare stars ACCRETION and ACCRETION disks mass loss and stellar winds cataclysmic BINARIES X-RAY BINARIES supernova REMNANTS active galactic nuclei X-RAY BURSTS gamma-ray BURSTS gravitational waves
Physical and toxicological profiles of human IAPP amyloids and plaques
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作者 Aleksandr Kakinen Yunxiang Sun +9 位作者 Ibrahim Javed Ava Faridi Emily H.Pilkington Pouya Faridi Anthony W.Purcell Ruhong Zhou Feng Ding Sijie Lin Pu Chun Ke Thomas P.Davis 《科学通报:英文版》 SCIE EI CSCD 2019年第1期26-35,共10页
Although much has been learned about the fibrillization kinetics,structure and toxicity of amyloid proteins,the properties of amyloid fibrils beyond the saturation phase are often perceived as chemically and biologica... Although much has been learned about the fibrillization kinetics,structure and toxicity of amyloid proteins,the properties of amyloid fibrils beyond the saturation phase are often perceived as chemically and biologically inert,despite evidence suggesting otherwise.To fill this knowledge gap,we examined the physical and biological characteristics of human islet amyloid polypeptide (IAPP)fibrils that were aged up to two months.Not only did aging decrease the toxicity of IAPP fibrils,but the fibrils also sequestered fresh IAPP and suppressed their toxicity in an embryonic zebrafish model.The mechanical properties of IAPP fibrils in different aging stages were probed by atomic force microscopy and sonication,which displayed comparable stiffness but age-dependent fragmentation,followed by self-assembly of such fragments into the largest lamellar amyloid structures reported to date.The dynamic structural and toxicity profiles of amyloid fibrils and plaques suggest that they play active,long-term roles in cell degeneration and may be a therapeutic target for amyloid diseases. 展开更多
关键词 IAPP AMYLOID PLAQUE Self assembly Toxicity
Psychophysics of the hoverfly: categorical or continuous color discrimination?
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作者 Lea Hannah Adrian G. Dyer +2 位作者 Jair E. Garcia Alan Dorin Martin Burd 《动物学报:英文版》 SCIE CAS CSCD 2019年第4期483-492,共10页
There is increasing interest in flies as potentially important pollinators. Flies are known to have a complex visual system, in eluding 4 spectral classes of photoreceptors that con tribute to the perception of color.... There is increasing interest in flies as potentially important pollinators. Flies are known to have a complex visual system, in eluding 4 spectral classes of photoreceptors that con tribute to the perception of color. Our current understanding of how color signals are perceived by flies is based on data for the blowfly Lucilia sp., which after being conditi oned to rewarded mono chromatic light stimuli, showed evidenee of a categorical color visual system. The resulting opponent fly color space has 4 distinct categories, and has been used to interpret how some fly pollinators may perceive flower colors. However, formal proof that flower flies (Syrphidae) only use a simple, categorical color process remains outstanding. In free-flying experiments, we tested the hoverfly Eristalis tenax, a Batesian mimic of the honeybee, that receives its nutrition by visiting flowers. Using a range of broadband similar-dissimilar color stimuli previously used to test color perception in pollinating hymenopteran species, we evaluated if there are steep changes in behavioral choices with continuously increasing color differences as might be expected by categorical color processing. Our data revealed that color choices by the hoverfly are mediated by a continuous monotonic function. Thus, these flies did not use a categorical processing, but showed evidenee of a color discrimination function similar to that observed in several bee species. We therefore empirically provide data for the minimum color distanee that can be discriminated by hoverflies in fly color space, enabling an improved un derstandi ng of plant-poll in ator interactions with a non-model insect species. 展开更多
关键词 chromatic signal COLOR model floral COLOR fly POLLINATION plant-pollinator vision
National Spinal Cord Injury Registry of Iran(NSCIR-IR)-a critical appraisal of its strengths and weaknesses
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作者 Mahdi Sharif-Alhoseini Zahra Azadmanjir +15 位作者 Mohsen Sadeghi-Naini Zahra Ghodsi Khatereh Naghdi Mahdi Mohammadzadeh Amir AzarHomayoun Kazem Zendehdel Moein Khormali Farideh Sadeghian Seyed Behzad Jazayeri Mojtaba Sehat Habibollah Pirnejad Edward C.Benzel Gerard O'Reilly Michael G.Fehlings Alexander R.Vaccaro Vafa Rahimi-Movaghar 《中华创伤杂志:英文版》 CAS CSCD 2019年第5期300-303,共4页
The National Spinal Cord Injury Registry of Iran(NSCIR-IR)is a not-for-profit,hospital-based,and prospective observational registry that appraises the quality of care,long-term outcomes and the personal and psychologi... The National Spinal Cord Injury Registry of Iran(NSCIR-IR)is a not-for-profit,hospital-based,and prospective observational registry that appraises the quality of care,long-term outcomes and the personal and psychological burden of traumatic spinal cord injury in Iran.Benchmarking validity in every registry includes rigorous attention to data quality.Data quality assurance is essential for any registry to make sure that correct patients are being enrolled and that the data being collected are valid.We reviewed strengths and weaknesses of the NSCIR-IR while considering the methodological guidelines and recommendations for efficient and rational governance of patient registries.In summary,the steering committee,funded and maintained by the Ministry of Health and Medical Education of Iran,the international collaborations,continued staff training,suitable data quality,and the ethical approval are considered to be the strengths of the registry,while limited human and financial resources,poor interoperability with other health systems,and time-consuming processes are among its main weaknesses. 展开更多
关键词 SPINAL CORD INJURIES Injury REGISTRIES Data accuracy Iran
Honeybees prefer novel insect-pollinated flower shapes over bird-pollinated flower shapes
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作者 Scarlett R. Howard Mani Shrestha +4 位作者 Juergen Schramme Jair E. Garcia Aurore AvARGUES-WEBER Andrew D. Greentree Adrian G. DYER 《动物学报:英文版》 SCIE CAS CSCD 2019年第4期457-465,共9页
Plant-pollinator in teractio ns have a fundame ntal in fluence on flower evolution. Flower color signals are frequently tuned to the visual capabilities of important pollinators such as either bees or birds, but far l... Plant-pollinator in teractio ns have a fundame ntal in fluence on flower evolution. Flower color signals are frequently tuned to the visual capabilities of important pollinators such as either bees or birds, but far less is known about whether flower shape in fluences the choices of pollinators. We tested European honeybee Apis mellifera pref ere nces using novel achromatic (gray-scale) images of 12 insect-pollinated and 12 bird-pollinated native Australian flowers in Germany;thus, avoiding in flue nces of color, odor, or prior experie nee. In depende nt bees were tested with a number of parameterized images specifically desig ned to assess pref ere nces for size, shape, brightness, or the number of flower-like shapes prese nt in an image. We show that honeybees have a pref ere nee for visiti ng images of in sect-polli nated flowers and such a pref ere nee is most-likely mediated by holistic in formati on rather than by in dividual image parameters. Our results in dicate an giosperms have evolved flower shapes which in fluence the choice behavior of importa nt pollinators, and thus suggest spatial achromatic flower properties are an important part of visual signaling for plantpollinator in teractions. 展开更多
关键词 ANGIOSPERM Apis MELLIFERA (European honeybee) bird-pollinated flower insect-pollinated POLLINATOR
The utility of coronary computed tomography angiography in elderly patients 预览
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作者 Jordan Laggoune Nitesh Nerlekar +4 位作者 Kiran Munnur Brian SH Ko James D Cameron Sujith Seneviratne Dennis TL Wong 《老年心脏病学杂志:英文版》 SCIE CAS CSCD 2019年第7期507-513,共7页
Background Coronary computed tomography angiography(CCTA)is often avoided in elderly patients due to a presumption that a high proportion of patients will have heavily calcified plaque limiting an accurate assessment.... Background Coronary computed tomography angiography(CCTA)is often avoided in elderly patients due to a presumption that a high proportion of patients will have heavily calcified plaque limiting an accurate assessment.We sought to assess the image quality,luminal stenosis and utility of CCTA in elderly patients with suspected coronary artery disease(CAD)and stable chest pain.Methods Retrospective analysis of elderly patients(>75 years)who underwent 320-detector row CCTA between 2012–2017 at MonashHeart.The CCTA was analysed for degree maximal coronary stenosis by CAD-RADS classification,image quality by a 5-point Likert score(1-poor,2-adequate,3-good,4-very good,5-excellent)and presence of artefact limiting interpretability.Results 1011 elderly patients(62%females,78.8±3.3 years)were studied.Cardiovascular risk factor prevalence included:hypertension(65%),hyperlipidaemia(48%),diabetes(19%)and smoking(21%).The CCTA was evaluable in 68%of patients which included 52%with non-obstructive CAD(<50%stenosis),48%with obstructive CAD(>50%)stenosis.Mean Likert score was 3.1±0.6 corresponding to good image quality.Of the 323(32%)of patients with a non-interpretable CCTA,80%were due to calcified plaque and 20%due to motion artefact.Male gender(P=0.009),age(P=0.02),excess motion(P<0.01)and diabetes mellitus(P=0.03)were associated with non-interpretable CCTA.Conclusion Although CCTA is a feasible non-invasive tool for assessment of elderly patients with stable chest pain,clinicians should still be cautious about referring elderly patients for CCTA.Patients who are male,diabetic and>78 years of age are significantly less likely to have interpretable scans. 展开更多
关键词 CORONARY artery calcium CORONARY CT ANGIOGRAPHY Multi-detector ROW CT The ELDERLY
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Risk stratification for coronary artery disease in multi-ethnic populations:Are there broader considerations for cost efficiency? 预览
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作者 Pupalan Iyngkaran William Chan +5 位作者 Danny Liew Jalal Zamani John D Horowitz Michael Jelinek David L Hare James A Shaw 《世界方法学杂志》 2019年第1期1-19,共19页
Coronary artery disease(CAD)screening and diagnosis are core cardiac specialty services.From symptoms,autopsy correlations supported reductions in coronary blood flow and dynamic epicardial and microcirculatory corona... Coronary artery disease(CAD)screening and diagnosis are core cardiac specialty services.From symptoms,autopsy correlations supported reductions in coronary blood flow and dynamic epicardial and microcirculatory coronaries artery disease as etiologies.While angina remains a clinical diagnosis,most cases require correlation with a diagnostic modality.At the onset of the evidence building process much research,now factored into guidelines were conducted among population and demographics that were homogenous and often prior to newer technologies being available.Today we see a more diverse multi-ethnic population whose characteristics and risks may not consistently match the populations from which guideline evidence is derived.While it would seem very unlikely that for the majority,scientific arguments against guidelines would differ,however from a translational perspective,there will be populations who differ and importantly there are cost-efficacy questions,e.g.,the most suitable first-line tests or what parameters equate to an adequate test.This article reviews non-invasive diagnosis of CAD within the context of multi-ethnic patient populations. 展开更多
关键词 Cost efficacy CORONARY artery DISEASE CORONARY heart DISEASE ETHNICITY Outcomes Risk STRATIFICATION
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Static coarsening behaviour of lamellar microstructure in selective laser melted Ti–6Al–4V
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作者 Sheng Cao Qiaodan Hu +9 位作者 Aijun Huang Zhuoer Chen Ming Sun Jiahua Zhang Chenxi Fu Qingbo Jia Chao Voon Samuel Lim Rodney R.Boyer Yi Yang Xinhua Wu 《材料科学技术学报:英文版》 SCIE EI CAS CSCD 2019年第8期1578-1586,共9页
Static coarsening mechanism of selective laser melted(SLMed) Ti–6Al–4V with a lamellar microstructure was established at temperatures from 700℃ to 950℃. Microstructure evolution revealed that high heat treatment t... Static coarsening mechanism of selective laser melted(SLMed) Ti–6Al–4V with a lamellar microstructure was established at temperatures from 700℃ to 950℃. Microstructure evolution revealed that high heat treatment temperature facilitated martensite decomposition and promoted lamellae growth. At each temperature, the growth rate decreased with increasing holding time. The static coarsening behaviour of SLMed Ti–6Al–4V can be interpreted by Lifshitz, Slyozov, and Wagner(LSW) theory. The coarsening coefficient were 0.33, 0.33–0.4, 0.4–0.5 for 700–800℃, 900℃ and 950℃, respectively. This indicated the coarsening mechanism was bulk diffusion at 700–800℃, and a combination of bulk diffusion and interface reaction at 900℃ and 950℃ conditions. 展开更多
关键词 SELECTIVE LASER MELTING Ti–6Al–4V Microstructure Heat treatment
Ambiguous temperature difference in aerodynamic levitation process: Modelling, solving and application
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作者 Xuan Ge Xiaowei Xu +5 位作者 Qiaodan Hu Wenquan Lu Liang Yang Sheng Cao Mingxu Xia Jianguo Li 《材料科学技术学报:英文版》 SCIE EI CAS CSCD 2019年第8期1636-1643,共8页
The aerodynamic levitation provides an efficient technique for the research on thermophysical properties and solidification behavior of refractory materials. However, there is a nonnegligible temperature differences a... The aerodynamic levitation provides an efficient technique for the research on thermophysical properties and solidification behavior of refractory materials. However, there is a nonnegligible temperature differences across sample, causing unexpected uncertainty of measurement, such as, thermal expansivity and undercooling limit. We establish thermal filed model with properly simplified boundary condition, and derive quantitative expressions of this ambiguous temperature difference. Here we show that the temperature difference not only related to the average temperature, relative size and thermal conductivity of sample, but significantly influenced by the rotation pattern of sample. A huge temperature differences is almost inevitable when the sample with low thermal conductivity and high melting point is smelted in stationary suspension pattern, however, a drastically reduction of temperature difference can be fulfilled by simply making the sample rotation in up to down pattern. The thermal filed simulation was used to confirm the validity of these theoretical expressions. This work shed light on temperature difference in aerodynamic levitation. Based on this work, one can simply estimate the extent of temperature difference across the sample, and regulated that conveniently if needed, which benefit for novel material preparation and solidification mechanism study based on this technique. 展开更多
关键词 SOLIDIFICATION LEVITATION MODELLING Temperature DIFFERENCE
Balance Control of a Biped Robot on a Rotating Platform Based on Efficient Reinforcement Learning 预览
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作者 Ao Xi Thushal Wijekoon Mudiyanselage +1 位作者 Dacheng Tao Chao Chen 《自动化学报:英文版》 CSCD 2019年第4期938-951,共14页
In this work,we combined the model based reinforcement learning(MBRL)and model free reinforcement learning(MFRL)to stabilize a biped robot(NAO robot)on a rotating platform,where the angular velocity of the platform is... In this work,we combined the model based reinforcement learning(MBRL)and model free reinforcement learning(MFRL)to stabilize a biped robot(NAO robot)on a rotating platform,where the angular velocity of the platform is unknown for the proposed learning algorithm and treated as the external disturbance.Nonparametric Gaussian processes normally require a large number of training data points to deal with the discontinuity of the estimated model.Although some improved method such as probabilistic inference for learning control(PILCO)does not require an explicit global model as the actions are obtained by directly searching the policy space,the overfitting and lack of model complexity may still result in a large deviation between the prediction and the real system.Besides,none of these approaches consider the data error and measurement noise during the training process and test process,respectively.We propose a hierarchical Gaussian processes(GP)models,containing two layers of independent GPs,where the physically continuous probability transition model of the robot is obtained.Due to the physically continuous estimation,the algorithm overcomes the overfitting problem with a guaranteed model complexity,and the number of training data is also reduced.The policy for any given initial state is generated automatically by minimizing the expected cost according to the predefined cost function and the obtained probability distribution of the state.Furthermore,a novel Q(λ)based MFRL method scheme is employed to improve the policy.Simulation results show that the proposed RL algorithm is able to balance NAO robot on a rotating platform,and it is capable of adapting to the platform with varying angular velocity. 展开更多
关键词 BIPED robot GAUSSIAN processes(GP) REINFORCEMENT learning TEMPORAL DIFFERENCE
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Water Pollution Control for Sustainable Development 预览
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作者 Ana Deletic Huanting Wang 《工程(英文)》 2019年第5期839-840,共2页
1.Introduction Water pollution is the major cause of ecological degradation on our planet;it directly affects human water supplies,often with serious consequences to public health.A wide range of contaminants—includi... 1.Introduction Water pollution is the major cause of ecological degradation on our planet;it directly affects human water supplies,often with serious consequences to public health.A wide range of contaminants—including chemicals,pathogens,and nutrients—has been and is currently being introduced into the natural environment.Household and industrial effluents,as well as urban and agricultural runoffs,are damaging aquatic ecosystems on a scale never seen before. 展开更多
关键词 SUSTAINABLE RUNOFF PLANET
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Aurone derivatives as Vps34 inhibitors that modulate autophagy
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作者 Guodong Li Joshua William Boyle +6 位作者 Chung-Nga Ko Wu Zeng Vincent Kam Wai Wong Jian-Bo Wan Philip Wai Hong Chan Dik-Lung Ma Chung-Hang Leung 《药学学报:英文版》 CSCD 2019年第3期537-544,共8页
We report in this study the identification of a natural product-like antagonist(1a) of Vps34 as a potent autophagy modulator via structure-based virtual screening. Aurone derivative 1a strongly inhibited Vps34 activit... We report in this study the identification of a natural product-like antagonist(1a) of Vps34 as a potent autophagy modulator via structure-based virtual screening. Aurone derivative 1a strongly inhibited Vps34 activity in cell-free and cell-based assays. Significantly, 1a prevents autophagy in human cells induced either by starvation or by an mT OR inhibitor. In silico modeling and kinetic data revealed that 1a could function as an ATP-competitive inhibitor of Vps34. Moreover, it suppressed autophagy in vivo and without inducing heart or liver damage in mice. 1a could be utilized as a new motif for more selective and efficacious antagonists of Vps34 for the potential treatment of autophagy-related human diseases. 展开更多
关键词 AUTOPHAGY Natural products Vps34 Inhibitor STRUCTURE-BASED virtual screening VESICLE TRAFFICKING Heart or liver damage AURONE derivative
In-situ study on hydrogen bubble evolution in the liquid Al/solid Ni interconnection by synchrotron radiation X-ray radiography
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作者 Zongye Ding Qiaodan Hu +6 位作者 Wenquan Lu Xuan Ge Sheng Cao Siyu Sun Tianxing Yang Mingxu Xia Jianguo Li 《材料科学技术学报:英文版》 SCIE EI CAS CSCD 2019年第7期1388-1392,共5页
Synchrotron X-ray radiography was used to carry out an in-situ observation of the hydrogen bubble evolution in the liquid Al/solid Ni interconnection. The individual bubble mainly grows in a stochastic way during heat... Synchrotron X-ray radiography was used to carry out an in-situ observation of the hydrogen bubble evolution in the liquid Al/solid Ni interconnection. The individual bubble mainly grows in a stochastic way during heating. The size distribution for groups of bubbles follows a Gaussian distribution in the early stage and Lifshitz-Slyozov-Wagner(LSW) diffusion controlled distribution in the final stage. The intermetallic compounds(IMCs) first form during solidification, following by the hydrogen bubbles. The bubbles between two adjacent Al3Ni grains grow unidirectionally along the liquid channel, with the bottom being impeded by the Al3Ni phase and the radius of the growth front being smaller. For the bubbles at triple junctions, they grow along the liquid channel and the crack with morphology transition. 展开更多
关键词 Synchrotron radiation LIQUID Al/solid NI INTERCONNECTION HYDROGEN BUBBLE Intermetallic compounds Growth behavior
Rac GTPases: domain-specific functions in neuronal development 预览
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作者 Steffen Norgaard Roger Pocock 《中国神经再生研究:英文版》 SCIE CAS CSCD 2019年第8期1367-1368,共2页
Understanding fundamental mechanisms governing axon outgrowth and guidance can inform the development of therapeutic strategies to restore neuronal function damaged though injury or disease. Axons navigate the extrace... Understanding fundamental mechanisms governing axon outgrowth and guidance can inform the development of therapeutic strategies to restore neuronal function damaged though injury or disease. Axons navigate the extracellular environment by responding to guidance cues that bind to cell surface receptors to relay information intracellularly via Rho GTPase family members, including the Rac GTPases. 展开更多
关键词 RAC GTPASES domain-specific FUNCTIONS NEURONAL DEVELOPMENT
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Expression of the oxygen-sensitive transcription factor subunit HIF-1α in patients suffering from secondary Raynaud syndrome
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作者 Lukas Andreas Heger Mark Kerber +7 位作者 Marcus Hortmann Samuel Robinson Maximilian Mauler Daniela Stallmann Daniel Duerschmied Christoph Bode Christoph Hehrlein Ingo Ahrens 《中国药理学报:英文版》 SCIE CAS CSCD 2019年第4期500-506,共7页
Anti-ischemic therapy remains a challenge due to the complexity of hypoxia response pathways. Hypoxia-inducible factor (HIF)-1 is a heterodimer tran scription factor con sisti ng of 2 sub units, HIF-1α and HIF-1β. H... Anti-ischemic therapy remains a challenge due to the complexity of hypoxia response pathways. Hypoxia-inducible factor (HIF)-1 is a heterodimer tran scription factor con sisti ng of 2 sub units, HIF-1α and HIF-1β. Hypoxia-depe ndent activatio n of HIF-1α regulates cellular 02 homeostasis. Raynaud syndrome (RS), as a comorbidity of the autoimmune disease systemic sclerosis (SS), is characterized by vasospasms that limit blood flow to the limbs, resulting in hypoxia. A single-center randomized study was con ducted to compare prostagla ndin E1 (PgEI) therapy with a treatme nt combi ning PgE1 and an en dotheli n-1 blocker, bosentan. A total of 30 patients suffering from SS with RS were enrolled. We examined the regulation of HIF-1α, its target heme oxygenase-1 (HMOX-1), and the serum levels of the HIF-1α protein in a subset of patients as well as in ten healthy individuals. The expression of HIF-1α and HMOX-1 in monocytes was measured using absolute plasmid-based quantitative real-time PCR, whereas serum HIF-1α levels were measured with ELISA. Samples were taken at the time of randomization and after 24 weeks. We found that HIF-1α and HMOX-1 mRNA expression in monocytes and serum HIF-1α protein levels were significantly higher in the SS/RS patients compared to the healthy control group. Single-drug therapy significantly increased HIF-1α and HMOX-1 mRNA expression in monocytes and serum HIF-1α protein levels in the SS/RS patients compared to those at the time of randomization, whereas combining PgE1 with an en dotheli n-1 blocker preve nted the further in creases in HIF-1α and HMOX-1 expressi on. We propose HIF-1α and HMOX-1 as novel markers for anti-ischemic therapy in RS. 展开更多
关键词 RAYNAUD syndrome hypoxia MONOCYTES HIF-1alpha HMOX-1 anti-ischemic therapy
QWB多属性效用量表的应用介绍
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作者 王雪雯 李顺平 +1 位作者 李文迪 陈钢 《中国卫生经济》 北大核心 2019年第2期5-7,共3页
多属性效用量表已成为主要的健康效用值测量工具。良好适应状态质量评估量表(Quality of Well-Being Scale,QWB)作为国际通用六大成人MAU量表之一,在国内应用较少。为促进QWB量表在国内的进一步应用,文章首先梳理了QWB量表的发展历程,... 多属性效用量表已成为主要的健康效用值测量工具。良好适应状态质量评估量表(Quality of Well-Being Scale,QWB)作为国际通用六大成人MAU量表之一,在国内应用较少。为促进QWB量表在国内的进一步应用,文章首先梳理了QWB量表的发展历程,然后介绍了QWB量表的健康状态描述系统和效用积分体系,并重点介绍了QWB量表在国内外的应用现状,最后对QWB量表的应用前景进行了总结与展望,这将为国内开展卫生经济学评价研究,尤其是效用值测量与成本–效用分析研究提供参考与借鉴。 展开更多
关键词 良好适应状态质量评估量表 健康效用 健康相关生命质量 成本–效用分析
SF系列量表演变及SF-6D多属性效用量表的介绍
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作者 刘笑晗 李顺平 陈钢 《中国卫生经济》 北大核心 2019年第2期8-11,共4页
多属性效用量表已成为主要的健康效用值测量工具。尽管六维健康调查简表(SF-6D)在国内的应用日益增多,但缺乏对SF系列量表如何演变为SF-6D多属性效用量表的相关介绍。为促进SF-6D量表在国内的进一步应用,首先简要梳理了SF系列量表的演变... 多属性效用量表已成为主要的健康效用值测量工具。尽管六维健康调查简表(SF-6D)在国内的应用日益增多,但缺乏对SF系列量表如何演变为SF-6D多属性效用量表的相关介绍。为促进SF-6D量表在国内的进一步应用,首先简要梳理了SF系列量表的演变,包括SF-18、SF-20、SF-36、SF-12以及SF-8等量表;然后介绍了SF-6D量表的健康状态描述系统和效用积分体系评分;最后对SF-6D量表在国内外的应用进行了总结,并对应用前景进行了展望。这将为国内开展经济学评价研究,尤其是效用值测量和成本–效用分析提供基础支持。 展开更多
关键词 健康调查系列量表 六维健康调查简表 健康效用值 多属性效用量表
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