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Pterosaur Research:Recent Advances and a Future Revolution

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Acta Geologica Sinica(english edition) 2012年第6期86卷 1366-1376页

作者： david W.e.HONe Department of earth Sciences University of Bristol School of Biological and Chemical Sciences Queen Mary University of London

In the years since the first description of a pterosaur specimen in 1784, pterosaur research has inevitably advanced considerably. However the last decade has arguably seen a much greater increase in our knowledge than the preceding two centuries. Since the turn of the new millennium, more than 40 new pterosaur genera and species have been described and whole new clades have been discovered, in addition to much new data being developed on pterosaur anatomy, functional morphology, palaeobiology, systematics, ecology and more. We are perhaps at the start of a golden age of pterosaur research and much as the dinosaurs underwent a revolution in the 1970s through to the early 1990s, now the Pterosauria are taking their turn. There is also a new and wider interest in pterosaur work as it attracts both more researchers and greater public interest. Pterosaurs appear to be an increasingly popular aspect of paleontology in popular culture and of interest to the media, both mainstream and digital.

关键词： paleontology Pterosauria science history of research academia

Opinion: the use of natural hazard modeling for decision making under uncertainty

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Forest ecosystems 2015年第2期2卷 139-142页

作者： david e Calkin Mike Mentis Forestry Sciences Laboratory US Forest Service Rocky Mountain Research Station Business & the environment Postnet Suite

Decision making to mitigate the effects of natural hazards is a complex undertaking fraught with uncertainty. Models to describe risks associated with natural hazards have proliferated in recent years. Concurrently, there is a growing body of work focused on developing best practices for natural hazard modeling and to create structured evaluation criteria for complex environmental models. However, to our knowledge there has been less focus on the conditions where decision makers can confidently rely on results from these models. In this review we propose a preliminary set of conditions necessary for the appropriate application of modeled results to natural hazard decision making and provide relevant examples within US wildfire management programs.

关键词： the use of natural hazard modeling for decision making under uncertainty

Bmi-1, stem cells and prostate carcinogenesis

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Asian Journal of Andrology 2011年第3期13卷 353-354页

作者： david Moscatelli e Lynette Wilson Department of Cell Biology NewYork University School of Medicine New York NY 10016 USA NYU Cancer Institute New York University School of Medicine New York NY 10016 USA Department of Urology New York University School of Medicine New York NY 10016. USA

Malignant transformation is likely to arise in a subset of organ-specific primitive cells that are subverted to acquire the properties of uncontrolled self-renewal. It is therefore likely that stem cells and tumorinitiating cells share many properties and that an understanding of the biology of normal stem cells and the identification of the pathways and molecules that regulate their self-renewal may result in our ability to design inhibitors that control the growth of tumor cells.

关键词： Cells Lymphocytes Regulations Stems Property Properties

On ultrahigh temperature crustal metamorphism:Phase equilibria,trace element thermometry,bulk composition,heat sources,timescales and tectonic settings

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Geoscience Frontiers 2015年第3期6卷 311-356页

作者： david e.Kelsey Martin Hand Department of Geology and Geophysics School of Physical SciencesThe University of Adelaide

Ultrahigh temperature （UHT） metamorphism is the most thermally extreme form of regional crustal metamorphism, with temperatures exceeding 900 ℃. UHT crustal metamorphism is recognised in more than 50 localities globally in the metamorphic rock record and is accepted as ＇normal＇ in the spectrum of regional crustal processes. UHT metamorphism is Wpically identified on the basis of diagnostic mineral assemblages such as sapphirine ＋ quartz, orthopyroxene ＋ sillimanite ＋ quartz and osumilite in Mg-Al- rich rock compositions, now usually coupled with pseudosection-based thermobarometry using internally-consistent thermodynamic data sets and/or Al-in-Orthopyroxene and ternary feldspar thermobarometry. Significant progress in the understanding of regional UHT metamorphism in recent years includes：（1） development of a ferric iron activity-composition thermodynamic model for sapphirine, allowing phase diagram calculations for oxidised rock compositions; （2） quantification of UHT conditions via trace element thermometry, with Zr-in-rutile more commonly recording higher temperatures than Ti-in-zircon. Rutile is likely to be stable at peak UHT conditions whereas zircon may only grow as UHT rocks are cooling. In addition, the extent to which Zr diffuses out of rutile is controlled by chemical communication with zircon; （3） more fully recognising and utilising temperature-dependent thermal properties of the crust, and the possible range of heat sources causing metamorphism in geodynamic modelling studies; （4） recognising that crust partially melted either in a previous event or earlier in a long-duration event has greater capacity than fertile, unmelted crust to achieve UHT conditions due to the heat energy consumed by partial melting reactions; （5） more strongly linking U-Pb geochronological data from zircon and monazite to P-T points or path segments through using Y ＋ Ree partitioning between accessory and major phases, as well as phase diagrams incorporating Zr and Ree; and （

关键词： Sapphirine + quartz P-T pseudosections Zr-in-rutile Ti-in-zircon U-Pb geochronology Subduction

Sources and significance of variation in basal,summit and maximal metabolic rates in birds

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Current Zoology 2010年第6期56卷 741-758页

作者： Andrew e. MCKeCHNIe david L. SWANSON DST/NRF Centre of excellence at the Percy FitzPatrick Institute Department of Zoology and EntomologyUniversity of Pretoria Department of Biology University of South Dakota

The rates at which birds use energy may have profound effects on fitness, thereby influencing physiology, behavior, ecology and evolution. Comparisons of standardized metabolic rates （e.g., lower and upper limits of metabolic power output） present a method for elucidating the effects of ecological and evolutionary factors on the interface between physiology and life history in birds. In this paper we review variation in avian metabolic rates [basal metabolic rate （BMR; minimum normothermic metabolic rate）, summit metabolic rate （Msum; maximal thermoregulatory metabolic rate）, and maximal metabolic rate （MMR; maximal exercise metabolic rate）], the factors associated with this variation, the evidence for functional links between these metabolic traits, and the ecological and evolutionary significance of avian metabolic diversity. Both lower and upper limits to metabolic power production are phenotypically flexible traits, and vary in association with numerous ecological and evolutionary factors. For both inter- and intraspecific comparisons, lower and upper limits to metabolic power production are generally upregulated in response to energetically demanding conditions and downregulated when energetic demands are relaxed, or under conditions of energetic scarcity. Positive correlations have been documented between BMR, Msum and MMR in some, but not all studies on birds, providing partial support for the idea of a functional link between lower and upper limits to metabolic power production, but more intraspecific studies are needed to determine the robustness of this conclusion. Correlations between BMR and field metabolic rate （or daily energy expenditure） in birds are variable, suggesting that the linkage between these traits is subject to behavioral adjustment, and studies of the relationship between field and maximal metabolic rates are lacking. Our understanding of avian metabolic diversity would benefit from future studies of：（1） the functional and mechanistic li

关键词： Phenotypic flexibility Reaction norms Basal metabolic rate Maximal metabolic rate Birds

ORIGINS OF POTASH DePOSITS IN THe QAIDAM BASIN, CHINA

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Science China Chemistry 1990年第2期33卷 198-210页

作者：孙大鹏 david e.LOCK Qinghai Institute of Salt Lakes Academia Sinica Xining 810008 PRC Australian National University Canberra Australia

The Qaidam Basin is a typically continental potash-bearing basin, which is comparatively rare in other countries. The potash deposits are widespread in the Quaternary salt lakes of the mid-western basin. At the same time, there exist many favourable conditions for the formation of potash deposits: (ⅰ)the sufficient source of potassium, (ⅱ) the optimum migration and accumulation processes of potassium, and (ⅲ) proper physico-chemical environments for separating potash salts. Owing to the differences in the supplying conditions for the external water to lake-basin and in the chemical compositions of those salt lake brines, potash deposits of various models and various types were formed.

关键词： potash deposits sulphate-type chloride-type polyhalite.

Creation and validation of a novel low-cost dry lab for early resident training and assessment of robotic prostatectomy technical proficiency

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Current Urology 2024年第2期18卷 133-138页

作者： Kevin Kunitsky Abhishek Venkataramana Katherine e.Fero Jorge Ballon Jacob Komberg Robert Reiter Wayne Brisbane Institute of Urologic Oncology Department of UrologyDavid Geffen School of MedicineUniversity of CaliforniaLos AngelesCAUSA Charles e.Schmidt College of Medicine Florida Atlantic UniversityBoca RatonFLUSA

Purpose:To evaluate the preliminary validity and acceptability of a low-cost low-fidelity robotic surgery dry lab for training and assessing residents’technical proficiency with key robotic radical prostatectomy *** and methods:Three standardized inanimate tasks were created to simulate the radical prostatectomy steps of posterior dissection,neurovascular bundle release,and urethrovesical *** trainees and faculty at a single institution completed and evaluated each dry lab *** validity was evaluated by comparing task completion times and Global evaluative Assessment of Robotic Skills scores across four participant cohorts:medical students(n=5),junior residents(n=5),senior residents(n=5),and attending surgeons(n=7).Content validity,face validity,and acceptabilitywere evaluated through a posttask survey using a 5-point Likert ***:There was a significant difference in the individual and composite task completion times and Global evaluative Assessment of Robotic Skills scores across all participant cohorts(all pe model was rated favorably in terms of its content validity and acceptability for use in residency ***,model realism,compared with human tissue,was poorly *** dry lab production cost was less than US$***:This low-cost procedure-specific dry lab demonstrated evidence of content validity,construct validity,and acceptability for simulating key robotic prostatectomy technical steps and can be used to augment robot-assisted laparoscopic prostatectomy surgical training.

关键词： Robotic surgery education Radical prostatectomy Simulation Dry laboratory Validation

Prostate-specific antigen （PSA） screening： has the pendulum swung too far？

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Asian Journal of Andrology 2011年第5期13卷 655-656页

作者： Jason M Phillips e david Crawford Department of Urology University of Colorado HealthSciences Center Aurora CO 80045 USA

Prostate-specific antigen （PSA） along with digital rectal exam has been the standard for prostate cancer screening in the United States for the past 20 years.1 During this time period, the improved detection of prostate cancer decreased related mortality more than 30%.2 In fact, metastases and their comorbidities have decreased more than 75% since the early 1990s, resulting in a higher incidence of early organ-confined disease. While it is clear that prostate cancer mortality statistics have improved, it is unclear whether men are overscreened.

关键词： Diseases Phenotypic screening

Fo screen or not to screen： the prostate cancer dilemma

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Asian Journal of Andrology 2015年第1期17卷 44-45页

作者： Nelson N Stone e david Crawford Departments of Urology and Radiation Oncology The Icahn School of Medicine at Mount Sinai New York NY USA Department of Surgery Division of Urology and Radiation Oncology The Anschutz Cancer Center The University of Colorado Health Sciences Center. Aurora. CO. USA.

The european Randomized Study of Screening for Prostate （eRSPC） has updated their previous seminal report on prostate cancer mortality comparing screened men to controls. Now with 13 years follow-up, the rate ratio of prostate cancer mortality was 0.79 favoring the screened population. The authors concluded that there was a ＂substantial reduction in prostate cancer mortality attributable to testing with prostate-specific antigen （PSA）＂ but they also stated that a＂quantification of harms＂ needed to be addressed. The issue of harms was not addressed by the eRSPC （at least not in this report） and hence this additional statement most likely reflects the controversy currently surrounding the risks associated with over-diagnosis and treatment of indolent diseases inadvertently detected by a screening protocol, In addition, the positive results from this trial conflict with those of the prostate, lung, colorectal and ovarian （PLCO）2 study and reouire further elaboration.

关键词： ACTIVe SURVeILLANCe BIOPSY ANTIGeN