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Galaxy formation in the reionization epoch as hinted by WideField Camera 3 observations of the Hubble Ultra Deep Field

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Research in Astronomy and Astrophysics 2010年第9期10卷 867-904页

作者： Hao-j.ng Yan Rogier A. Windhorst Nimish E Hathi Seth H. Cohen Russell E.Ryan Robert W. O＇Connell patrick j. mccarthy Center for Cosmology and AstroParticle Physics The Ohio State University 191 West Woodruff Avenue Columbus OH 43210 USA School of Earth and Space Exploration Arizona State University Tempe AZ 85287 USA Department of Physics ＆ Astronomy University of California Riverside CA 92521 USA Department of Physics University of California One Shields Avenue Davis CA 95616 USA Astronomy Department University of Virginia P.O. Box 3818 Charlottesville VA 22903 USA Observatories of the Carnegie Institution of Washington 813 Santa Barbara Street Pasadena CA 91101 USA

We present a large sample of candidate galaxies at z ≈ 7 - 10, selected in the Hubble Ultra Deep Field using the new observations of the Wide Field Camera 3 that was recently installed on the Hubble Space Telescope. Our sample is composed of 20 z850-dropouts （four new discoveries）, 15 Y105-dropouts （nine new discoveries） and 20 j.25-dropouts （all new discoveries）. The surface densities of the Z850-dropouts are close to what was predicted by earlier studies, however, those of the Y105- and j.25-dropouts are quite unexpected. While no Y105- or j.25-dropouts have been found at AB ≤ 28.0 mag, their surface densities seem to increase sharply at fainter levels. While some of these candidates seem to be close to foreground galaxies and thus could possibly be gravitationally lensed, the overall surface densities after excluding such cases are still much higher than what would be expected if the luminosity function does not evolve from z ～ 7 to 10. Motivated by such steep increases, we tentatively propose a set of Schechter function parameters to describe the luminosity functions at z ≈8 and 10. As compared to their counterpart at z ≈ 7, here L^＊ decreases by a factor of ～ 6.5 and Ф^＊ increases by a factor of 17-90. Although such parameters are not yet demanded by the existing observations, they are allowed and seem to agree with the data better than other alternatives. If these luminosity functions are still valid beyond our current detection limit, this would imply a sudden emergence of a large number of low-luminosity galaxies when looking back in time to z ≈ 10, which, while seemingly exotic, would naturally fit in the picture of the cosmic hydrogen reionization. These early galaxies could easily account for the ionizing photon budget required by the reionization, and they would imply that the global star formation rate density might start from a very high value at z ≈ 10, rapidly reach the minimum at z≈ 7, and start to rise again towards z ≈ 6. In this scenario, the maj

关键词： cosmology observations -- cosmology early universe -- galaxies evolution -- galaxies luminosity function, mass function -- infrared galaxies

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Trip and mode choice decisions to out-patient health care facilities:A longitudinal analysis

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j.urnal of Management Science and Engineering 2022年第2期7卷 173-196页

作者： patrick mccarthy School of Economics Georgia Institute of TechnologyAtlanta30332USA Center for Economics Financeand ManagementHunan University Changsha410082China

This paper analyzes the impact of health indicators on an individual's trip and mode choices to out-patient care *** study's focus is an out-patient trip to a health care facility,and the source of data is the China Health and Retirement Longitudinal Study(CHARLS)for 2011.2013 and *** on a random utility framework,the study finds that making a rip to ureat an ilness or for a check-up increases the likelihood of an out-patient trip by 52 and 31 probability points,***-patient visits for which in-surance is not relevant,When the individual pays most of the out:of-pocket costs and when the facility is a public facility are also important *** and other per-sonal health factors have some but much more modest effects on one's trip *** analysis also identifies differential modal impacts of health indicators.A series of robustness tests generally confirm the results and identify areas for further *** a no-trip option,the biannual sunvey and infrequent out-patient trip-making mitigate endogeneity *** analysis has broad health policy and transportation implications for an ageing population whose share is increasing.

关键词： Health indicators Healthpolicy Out-patient Tripchoice Modechoice Ageing Longitudinal Random utility model China CHARLS

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On the Dirichlet form of three-dimensional Brownian motion conditioned to hit the origin

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Science China Mathematics 2019年第8期62卷 1477-1492页

作者： patrick j. Fitzsimmons Liping Li Department of Mathematics University of California at San Diego San Diego CA 92093-0112 USA RCSDS HCMS Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 China

Our concern in this paper is the energy form induced by an eigenfunction of a self-adj.int extension of the restriction of the Laplace operator to C_c^∞(R^3\j.).We will prove that this energy form is a regular Dirichlet form with core C_c^∞(R^3).The associated diffusion X behaves like a 3-dimensional Brownian motion with a mild radial drift when far from 0,subj.ct to an ever-stronger push toward 0 near that *** particular,j.is not a polar set with respect to *** diffusion X is rotation invariant,and admits a skew-product representation before hittingj.:its radial part is a diffusion on(0,∞)and its angular part is a time-changed Brownian motion on the sphere S^*** radial part of X is a"reflected"extension of the radial part of X^0(the part process of X before hittingj.).Moreover,X is the unique reflecting extension of X^0,but X is not a semi-martingale.

关键词： Dirichlet form reflected extension rotationally invariant process Fukushima’s decomposition

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Climate Change Adaptation for People and Nature:A Case Study from the ***

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Advances in Climate Change Research 2012年第1期3卷 22-37页

作者： patrick D.mccarthy The Nature Conservancy Santa Fe 87501U.S.

In the ***,global climate change,acting in concert with extant stressors such as urbanization and over-allocation of water resources,is changing ecosystems in measureable and sometimes dramatic ***-first century proj.ctions indicate accelerating climate change and cascading ecological *** observed to date include large-scale forest dieback,large and severe wildfires,and changes in the flow regimes of rivers and streams with attendant changes to riparian and aquatic *** temperatures and changing precipitation patterns are pushing ecosystems across physiological and ecological thresholds,causing widespread mortality and,in some cases,maj.r changes in composition,structure and *** changes have prompted action by the conservation community to reduce the adverse effects of climate *** Southwest Climate Change Initiative(SWCCI),a proj.ct led by The Nature Conservancy,works with local stakeholders in affected landscapes,reduces adverse impacts on ecological and social systems using scientific knowledge and practical *** Initiative has learned through practical experience that: 1) managers must embrace change and manage for resilience rather than resistance;2) strong local science-management partnerships are critical to effective adaptation planning and implementation;3) planners and managers must broaden the scope and accelerate the pace of conservation activities if ecosystem services are to be sustained;4) adaptation often does not require radically new or different management practices,rather,conservationists already have many of the tools they need;and 5) rapid documentation and widespread communication of methods and findings can build rapidly regional capacity for climate change *** experience suggests that adaptation efforts can be effective if they are focused at the local scale;employ learning networks;and engage in ecosystem-based adaptation:the sustainable management,conservation

关键词： climate change adaptation ecosystem-based adaptation ecological thresholds learning networks

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Geoparks： Celebrating Earth heritage, sustaining Local communities

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Episodes 2005年第4期28卷 274-278页

作者： patrick j. Mc Keever Nickolas Zouros Geological Survey of Northern Ireland Colby House Stranmillis Court Belfast BT9 5BF Ireland. Department of Geography University of the Aegean University Hill Mytilene GR-81100 Hellenic Republic.

For too long Earth Science has been the poor relative to Natural Sciences when it comes to conservation, preservation and public promotion. Today, however, in 25 territories across Europe, a combination of Earth Scientists, economists, professional marketers and local people are working together to promote the geological heritage of their areas. These European Geoparks not only advance the protection of their geological heritage but they also use it, in a truly sustainable way, to promote the economic well-being of the people who live there. With the full endorsement of UNESCO, this concept of geoparks is spreading to other parts of the world and is rapidly developing into a global concept. This article looks in detail at the geopark idea -- exactly what geoparks are, how they function, and what benefits they can bring both to geology and to the public.

关键词：地质公园地貌地质条件生态系统地质多样性

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A remark on Kac's scattering length formula

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Science China Mathematics 2013年第2期56卷 331-338页

作者： FITZSIMMONS patrick j. HE Ping YING j.anGang Department of Mathematics University of California at San Diego Department of Applied Mathematics Shanghai University of Finance and Economics School of Mathematics Fudan University

The scattering length formula was formulated and proved in special cases by Kac in 1974 and *** was discussed by a series of authors,including Taylor 1976,Tamura 1992 and Takahashi *** formula was proved by Takeda 2010 in symmetric case and by He 2011 assuming weak *** this article,we shall use the powerful tool of Kutznetsov measures to prove this formula in the general framework of right Markov processes without further assumptions.

关键词： scattering length Kuznetsov measure capacity

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Gut-associated lymphoid tissue or so-called “dome” carcinoma of the colon: Review

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World j.urnal of Gastrointestinal Oncology 2019年第1期11卷 59-70页

作者： Aoife j.mccarthy Runj.n Chetty Department of Anatomical Pathology Laboratory Medicine Program University Health Network Department of Laboratory Medicine and Pathobiology Faculty of Medicine University of Toronto

AIM To present a comprehensive review of the etiology, clinical features, macroscopic and pathological findings, and clinical significance of Gut-associated lymphoid tissue or "dome" carcinoma of the *** The English language medical literature on gut-or gastrointestinal-associated lymphoid tissue(GALT) or "dome" carcinoma of the colon was searched and *** GALT/dome-type carcinomas of the colon are thought to arise from the M-cells of the lymphoglandular complex of the intestine. They are typically asymptomatic and have a characteristic endoscopic plaque-or "dome"-like appearance. Although the histology of GALT/dome-type carcinomas displays some variability, they are characterized by submucosal localization, a prominent lymphoid infiltrate with germinal center formation, tumor-infiltrating lymphocytes, absence of desmoplasia, and dilated glands lined by columnar epithelial cells with bland nuclear features and cytoplasmic eosinophilia. None of the patients reported in the literature with follow-up have developed metastatic disease or local *** Increased awareness amongst histopathologists of this variant of colorectal adenocarcinoma is likely to lead to the recognition of more cases.

关键词： Dome-type carcinoma Gastrointestinal-associated lymphoid tissue carcinoma Gut-associated lymphoid tissue Lymphoglandular complex Colorectal cancer

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Early Cretaceous Tectonics and Evolution of the Tibetan Plateau

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Acta Geologica Sinica(English Edition) 2016年第3期90卷 847-857页

作者： WU Zhenhan ZHAO Zhen patrick j. BAROSH YE Peisheng Chinese Academy of Geological Sciences Beijing 100037 China P.j. Barosh andAssociates 103 Aaron Ave. Bristol RI 02809 USA Institute of Geomechanies Chinese Academy of Geological Sciences Beijing 100081 China

Selected geological data on Early Cretaceous strata, structures, magmatic plutons and volcanic rocks from the Kunlun to Himalaya Mountains reveal a new view of the Early Cretaceous paleo-tectonics and the related geodynamic movement of the Tibetan Plateau. Two maj.r paleo- oceans, the Mid-Tethys Ocean between the Qiangtang and Lhasa blocks, and the Neo-Tethys Ocean between the Lhasa and Himalayan blocks, existed in the Tibetan region in the Early Cretaceous. The Himalayan Marginal and South Lhasa Seas formed in the southern and northern margins of the Neo- Tethys Ocean, the Central Tibet Sea and the Qiangtang Marginal Sea formed in the southern and northern margins of the Mid-Tethys Ocean, respectively. An arm of the sea extended into the southwestern Tarim basin in the Early Cretaceous. Early Cretaceous intensive thrusting, magmatic emplacement and volcanic eruptions occurred in the central and northern Lhasa Block, while strike- slip formed along the Hoh-Xil and South Kunlun Faults in the northern Tibetan region. Early Cretaceous tectonics together with magmatic K20 geochemistry indicate an Early Cretaceous southward subduction of the Mid-Tethys Oceanic Plate along the Bangoin-Nuj.ang Suture which was thrust ~87 km southward during the Late Cretaceous-Early Cenozoic. No intensive thrust and magmatic emplacement occurred in the Early Cretaceous in the Himalayan and southern Lhasa Blocks, indicating that the spreading Neo-Tethys Oceanic Plate had not been subducted in the Early Cretaceous. To the north, terrestrial basins of red-beds formed in the Hoh-Xil, Kunlun, Qilian and the northeastern Tarim blocks in Early Cretaceous, and the Qiangtang Marginal Sea disappeared after the Qiangtang Block uplifted in the late Early Cretaceous.

关键词： Early Cretaceous paleo-tectonics subduction of the oceanic plate K20 geochemistry of granites Bangoin-Nuj.ang Suture the Tibetan Plateau

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SOME RECURRENCE FORMULAS FOR BOX SPLINES AND CONE SPLINES

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Analysis in Theory and Applications 2004年第4期20卷 297-306页

作者： patrick j. Van Fleet Department of Mathematics University of St. Thomas St. Paul MN 55105 USA

A degree elevation formula for multivariate simplex splines was given by Micchelli and extended to hold for multivariate Dirichlet splines in [8]. We report similar formulae for multivariate cone splines and box splines. To this end, we utilize a relation due to Dahmen and Micchelli that connects box splines and cone splines and a degree reduction formula given by Cohen, Lyche, and Riesenfeld in [2].

关键词： box spline cone spline degree elevation

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Determination of fractional energy loss of waves in nearshore waters using an improved high-order Boussinesq-type model

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Chinese j.urnal of Oceanology and Limnology 2009年第3期27卷 621-629页

作者：何海伦宋金宝 patrick j. Lynett 李爽 Institute of Oceanology Chinese Academy of Sciences Key Laboratory of Ocean Circulation and Waves(KLOCAW) Chinese Academy of Sciences Graduate School Chinese Academy of Sciences Department of Civil Engineering Texas A&M University

Fractional energy losses of waves due to wave breaking when passing over a submerged bar are studied systematically using a modified numerical code that is based on the high-order Boussinesq-type *** model is first tested by the additional experimental data,and the model's capability of simulating the wave transformation over both gentle slope and steep slope is ***,the model's breaking index is replaced and *** new breaking index,which is optimized from the several breaking indices,is not sensitive to the spatial grid length and includes the bottom *** tests show that the modified model with the new breaking index is more stable and efficient for the shallow-water wave ***,the modified model is used to study the fractional energy losses for the regular waves propagating and breaking over a submerged *** results have revealed that how the nonlinearity and the dispersion of the incident waves as well as the dimensionless bar height(normalized by water depth) dominate the fractional energy *** is also found that the bar slope(limited to gentle slopes that less than 1:10) and the dimensionless bar length(normalized by incident wave length) have negligible effects on the fractional energy losses.

关键词： breaking waves Boussinesq-type equations nearshore wave modeling fractional energy loss

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