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seismic anisotropy of upper mantle in eastern Tibetan Plateau and related crust-mantle coupling pattern

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science China Earth sciences 2007年第8期50卷 1150-1160页

作者： paul sILVER Lucy FLEsCH Carnegie Institution of Washington Washington DC 200015 USA

By using the polarization analysis of teleseismic sKs waveform data recorded at 116 seismic stations which respectively involved in China National Digital seismograph Network, and Yunnan, sichuan, Gansu and Qinghai regional digital networks, and portable broadband seismic networks deployed in sichuan, Yunnan and Tibet, we obtained the sKs fast-wave direction and the delay time between fast and slow waves of each station by use of the stacking analysis method, and finally acquired the fine image of upper mantle anisotropy in the eastern Tibetan Plateau and its adjacent regions. We analyzed the crust-mantle coupling deformation on the basis of combining the GPs observation results and the upper mantle anisotropy distribution in the study area. The Yunnan region out of the plateau has dif-ferent features of crust-mantle deformation from the inside plateau. There exists a lateral transitional zone of crust-mantle coupling in the eastern edge of the Tibetan Plateau, which is located in the region between 26° and 27°N in the west of sichuan and Yunnan. To the south of transitional zone, the fast-wave direction is gradually turned from s60°―70°E in southwestern Yunnan to near EW in south-eastern Yunnan. To the north of transitional zone in northwestern Yunnan and the south of western sichuan, the fast-wave direction is nearly Ns. From crust to upper mantle, the geophysical parameters (e.g. the crustal thickness, the Bouguer gravity anomaly, and tectonic stress direction) show the feature of lateral variation in the transitional zone, although the fault trend on the ground surface is inconsis-tent with the fast-wave direction. This transitional zone is close by the eastern Himalayan syntaxis, and it may play an important role in the plate boundary dynamics.

关键词： upper mantle anisotropy sKs wave fast-wave direction crust-mantle coupling lithospheric deformation

Mode-Locked Thulium Ytterbium Co-Doped Fiber Laser with Graphene Oxide Paper saturable Absorber

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Chinese Physics Letters 2015年第1期32卷 59-62页

作者： s. M. Azooz s. W. Harun H. Ahmad A. Halder M. C. paul M.Pal s. K. Bhadra Department of Electrical Engineering Faculty of Engineering University of Malaya Kuala Lumpur 50603 Malaysia Photonics Research Center University of Malaya Kuala Lumpur 50603 Malaysia Fiber Optics and Photonics Division Central Glass & Ceramic Research Institute CSIR Kolkata India

A mode-locked thulium ytterbium co-doped fiber laser （TYDFL） is proposed and demonstrated by using a commercial graphene oxide （GO） paper as saturable absorber （sA）. The GO paper is sandwiched between two fiber ferrules and incorporates a ring laser cavity to generate soliton pulse train operating at 1942.0nm at a threshold multimode pump power as low as 1.8 W. The mode-locked TYDFL has a repetition rate of 22.32 MHz and the calculated pulse width of 1.1 ns. Even though the sA has a low damage threshold, the easy fabrication of GO paper should promote its potentiM application in ultrafast photonics.

关键词： Mode-Locked Thulium Ytterbium Co-Doped Fiber Laser with Graphene Oxide Paper saturable Absorber sA GO

Review of trans-Mediterranean power grid interconnection:a regional roadmap towards energy sector decarbonization

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Global Energy Interconnection 2023年第1期6卷 115-126页

作者： Kaifeng Yu paul van son Global Energy Interconnection Development and Cooperation Organization Beijing 100031P.R.China Global Energy Interconnection Group Co.Ltd. Beijing 100031P.R.China Dii Desert Energy Dubai 487389United Arab Emirates

Climate change is becoming an important issue in all fields of infrastructure *** plays a core role in the decarbonized energy system’s path to a regional zero-emission pattern.A well-built trans-Mediterranean backbone grid can hedge the profound evolution of regional power generation,transmission,and *** date,only Turkey and the Maghreb countries(i.e.,Morocco,Algeria,and Tunisia)are connected with the Continental European synchronous *** south-and east-shore countries have insufficient interconnection infrastructures and synchronization difficulties that have proven to be major hurdles to the implementation of large-scale solar and wind projects and achievement of climate *** study analyzes the current trans-boundary grid interconnections and power and carbon emission portfolios in the Mediterranean *** align with the recently launched new climate target‘Fit for 55’program and the accelerated large-scale renewables target,a holistic review of projected trans-Mediterranean grids and their market,technical,and financial obstacles of implementation was *** south-and east-shore countries,major legal and regulatory barriers encompassing non-liberalized market structure,regulation gaps of taxation and transmission tariffs,and the private sector’s access rights need to be *** of domestic grids,substations,and harmonized grid codes and frequency,voltage,and communication technology standards among all trans-Mediterranean countries are physical prerequisites for implementing the Trans-Mediterranean Electricity *** addition,the mobilization of capital instruments along with private and international investments is indispensable for the realization of supranational transmission *** the final section of the decarbonization roadmap,the development of electric appliances,equipment,and vehicles with higher efficiency is inevitable in the decarbonized building,transportation,and industry sec

关键词： Mediterranean Grid interconnection Regional roadmap Power system Decarbonization Climate change

Mode-locked 2 μm fiber laser with a multi-walled carbon nanotube as a saturable absorber

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Chinese Optics Letters 2015年第3期13卷 10-13页

作者： s.M.Azooz F.Ahmad H.Ahmad s.W.Harun B.A.Hamida s.Khan A.Halder M.C.paul M.Pal s.K.Bhadra Department of Electrical Engineering Faculty of Engineering University of Malaya Photonics Research Center University of Malaya Department of Electrical and Computer Engineering International Islamic University MalaysiaJalan Gombak Fiber Optics and Photonics Division Central Glass & Ceramic Research InstituteCSIR

We propose and demonstrate a passively mode-locked fiber laser operating at 1951.8 nm using a commercial thulium-doped fiber （TDF） laser, a homemade double-clad thulium-ytterbium co-doped fiber （TYDF） as the gain media, and a multi-walled carbon nanotube （MWCNT） based saturable absorber （sA）. We prepare the MWCNT composite by mixing a homogeneous solution of MWCNTs with a diluted polyvinyl alcohol （PVA） polymer solution and then drying it at room temperature to form a film. The film is placed between two fiber connectors as a sA before it is integrated into a laser ring cavity. The cavity consists of a 2 m long TDF pumped by a 800 nm laser diode and a 15 m long homemade TYDF pumped by a 905 nm multimode laser diode. A stable mode-locking pulse with a repetition rate of 34.6 MHz and a pulse width of 10.79 ps is obtained when the 905 nm multimode pump power reaches 1.8-2.2 W, while the single-mode 800 nm pump power is fixed at 141.5 mW at all times. To the best of our knowledge, this is the first reported mode-locked fiber laser using a MWCNT-based sA.

关键词： MWCNTs mode Mode-locked 2 m fiber laser with a multi-walled carbon nanotube as a saturable absorber

Observing the stages of bystander intervention in virtual reality simulation

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World Journal of Emergency Medicine 2019年第3期10卷 145-151页

作者： David G. Buckler Alfredo Almodovar Jr paul snobelen Benjamin s. Abella Audrey Blewer Marion Leary Center for Resuscitation science University of Pennsylvania Philadelphia PA 19104 USA Peel Regional Paramedic service 1600 Bovaird Dr. E Brampton ON L6R 3S8 Canada Department of Community & Family Medicine Duke University Medical Center DUMC 2914 Durham NC 27710 USA school of Nursing University of Pennsylvania 418 Guardian Drive Philadelphia PA 19104 USA

BACKGROUND: Understanding bystander reactions to an emergency is an important component of effective training. Four stages of bystander intervention (BI) have been previously described: noticing the situation as a problem, interpreting when it is appropriate to intervene, recognizing personal responsibility to intervene, and knowing how to intervene. Using virtual reality (VR) to simulate emergencies such as sudden cardiac arrest (sCA) can be used to study these stages. METHODs: In a secondary analysis of an observational cohort study, we analyzed bystander self-effi cacy for stages of BI before and after simulated sCA. Each subject participated in a singleplayer, immersive, VR sCA scenario. subjects interacted with simulated bystanders through voice commands (“call 911”,“get an AED”). Actions taken in scenario, like performing CPR, were documented. scenario BI actions were compared based on dichotomized comfort/discomfort. REsULTs: From June 2016 to June 2017, 119 subjects participated. Average age was 37±14 years, 44% were female and 46% reported CPR training within 2 years. During the scenario, 98%“noticed the event” and “interpreted it as a problem”, 78%“took responsibility”, and 54%“possessed the necessary skills”. self-effi cacy increased from pre- to post-scenario: noticing the event increased from 80% to 96%;interpreting as a problem increased from 86% to 97%;taking responsibility increased from 56% to 93%;possessing necessary skills increased from 47% to 63%(PsION: self-efficacy to respond to an sCA event increased pre- to post-scenario. Bystanders who reported feeling comfortable “taking responsibility to intervene” during an emergency were more likely to take action during a simulated emergency.

关键词： Virtual reality Bystander intervention Emergency preparedness

single-particle cryo-EM: beyond the resolution

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National science Review 2019年第5期6卷 864-866页

作者： Jean-paul Armache Yifan Cheng Department of Biochemistry and Molecular Biology and the Huck Institutes of the Life sciences Pennsylvania State University Howard Hughes Medical Institute University of California San Francisco Department of Biochemistry and Biophysics University of California San Francisco

structural biology aims to provide structural insights into our understandings of biological processes at the atomic *** structures of biological macromolecules are often determinedby one of the three major methods:Xr... 详细信息

关键词： single-particle cryo-EM beyond the resolution

sodium and water perturbations in patients who had an acute stroke:clinical relevance and management strategies for the neurologist

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stroke & Vascular Neurology 2022年第3期7卷 258-266页

作者： Kevin C J Yuen Valerie sharf Elizabeth smith Minhwan Kim Alissya s M Yuen paul R MacDonald Departments of Neuroendocrinology and Neurosurgery Barrow Neurological InstitutePhoenixArizonaUSA University of Arizona College of Medicine and Creighton school of Medicine PhoenixArizonaUSA Department of Neurology Barrow Neurological InstitutePhoenixArizonaUSA Midwestern University GlendaleIllinoisUSA Creighton University school of Medicine PhoenixArizonaUSA University of California Davis DavisCaliforniaUSA

sodium and water perturbations,manifesting as hyponatraemia and hypernatraemia,are common in patients who had an acute stroke,and are associated with worse outcomes and increased *** non-stroke related causes of sodium and water perturbations in these patients include underlying comorbidities and concomitant ***,hospitalised patients who had an acute stroke may receive excessive intravenous hypotonic solutions,have poor fluid intake due to impaired neurocognition and consciousness,may develop sepsis or are administered drugs(eg,mannitol);factors that can further alter serum sodium *** and water perturbations can also be exacerbated by the development of endocrine consequences after an acute stroke,including secondary adrenal insufficiency,syndrome of inappropriate antidiuretic hormone secretion and diabetes ***,COVID-19 infection has been reported to increase the risk of development of sodium and water perturbations that may further worsen the outcomes of patients who had an acute *** there are currently no accepted consensus guidelines on the management of sodium and water perturbations in patients who had an acute stroke,we conducted a systematic review of the literature published in English and in peer-reviewed journals between January 2000 and December 2020,according to PRIsMA guidelines,to assess on the current knowledge and clinical practices of this *** this review,we discuss the signs and symptoms of hyponatraemia and hypernatraemia,the pathogenesis of hyponatraemia and hypernatraemia,their clinical relevance,and we provide our recommendations for effective treatment strategies for the neurologist in the management of sodium and water perturbations in commonly encountered aetiologies of patients who had an acute stroke.

关键词： patients impaired consequences

Levy Constrained search in Fock space：An Alternative Approach to Noninteger Electron Number

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物理化学学报 2018年第6期34卷 625-630页

作者： AYERs paul W. LEVY Mel Department of Chemistry and Chemical Biology McMaster University Hamilton Ontario L8S 4M1 Canada. Department of Physics North Carolina A&T State University Greensboro NC 27411 USA. Department of Chemistry Duke University Durham NC 2770

By extending the Levy wavefunction constrained search to Fock space,one can define a wavefunction constrained search for electron densities in systems having noninteger number of *** pure-state v-representable densities,the results are equivalent to what one would obtain with the zero-temperature grand canonical *** other cases,the wavefunction constrained search in Fock space presents an upper bound to the grand canonical ensemble *** advantage of the Fock-space wavefunction constrained search functional over the zero-temperature grand-canonical ensemble constrained search functional is that certain specific excited states(i.e.,those that are not ground-statev-representable) are the stationary points of the Fock-space ***,a potential disadvantage of the Fock-space constrained search functional is that it is not convex.

关键词： Density functional theory Levy constrained search functional Fock space Fractional electron number Excited-state density functional theory Universal density functional Zero temperature grand canonicalensemble Convexity

Analysis of structural distortion in Eshelby twisted InP nanowires by scanning precession electron diffraction

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Nano Research 2019年第4期12卷 939-946页

作者： Daniel Ugarte Luiz H. G. Tizei Monica A. Cotta Caterina Ducati paul A. Midgley Alexander s. Eggeman Instituto de Ftsica "Gleb Wataghin" Universidade Estadual de Campinas-UNICAMP CEP 13083-859 Campinas - SE Brazil Department of Materials science and Metallurgy University of Cambridge Cambridge CB3 OFS UK Laboratoire de Physique des solides CNRS UMR8502 Univ. Paris Sud 91405 Orsay France school of Materials University of Manchester Manchester M13 9PL UK

Tran smissio n electro n microscopes (TEM) are widely used in nan otech no logy research. However, it is still challe nging to characterize nano scale objects;their small size coupled with dynamical diffraction makes interpret!ng real- or reciprocal-space data difficult. scanning precession electron diffraction ((s)PED) represents an invaluable contribution, reducing the dynamical contributions to the diffraction pattern at high spatial resolution. Here a detailed analysis of wurtzite InP nanowires (30-40 nm in diameter) containing a screw dislocation and an associated wire lattice torsion is presented. It has been possible to characterize the dislocation with great detail (Burgers and line vector, handedness). Through careful measurement of the strain field and comparison with dynamical electron diffraction simulations, this was found to be compatible with a Burgers vector modulus equal to one hexagonal lattice cell parameter despite the observed crystal rotation rate being larger (ca. 20%) than that predicted by classical elastic theory for the nominal wire diameter. These findings corroborate the importance of the (s)PED technique for characterizing nano scale materials.

关键词： electron microscopy seanning precession electron diffraction Eshelby twist screw dislocation nanowire indium phosphide