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人与自然 2013年第4期 64-73页

作者：张蒙蒙 kent matthews Herman du Plessis Robert StahlRobert Stahl

薰衣草让这个平静的法国南部山区一下子成了世人皆知的世外桃源，人们向往着那片迷幻的薰衣草花海，更憧憬着那种简单无忧，与自然和谐相处的生活方式，于是纷至沓来，开始一场寻香之旅。

关键词：普罗旺斯南部山区生活方式和谐相处薰衣草

A planet in transition:The onset of plate tectonics on Earth between 3 and 2 Ga?

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Geoscience Frontiers 2018年第1期9卷 51-60页

作者： kent C.Condie Department of Earth and Environmental Science New Mexico Tech

Many geological and geochemical changes are recorded on Earth between 3 and 2 *** the more important of these are the following:(1)increasing proportion of basalts with"arc-like"mantle sources;(2)an increasing abundance of basalts derived from enriched(EM)and depleted(DM)mantle sources;(3)onset of a Great Thermal Divergence in the mantle;(4)a decrease in degree of melting of the mantle;(5)beginning of large lateral plate motions;(6)appearance of eclogite inclusions in diamonds;(7)appearance and rapid increase in frequency of collisional orogens;(8)rapid increase in the production rate of continental crust as recorded by zircon age peaks;(9)appearance of ophiolites in the geologic record,and(10)appearance of global LIP(large igneous province)events some of which correlate with global zircon age *** of these changes may be tied directly or indirectly to cooling of Earth's mantle and corresponding changes in convective style and the strength of the lithosphere,and they may record the gradual onset and propagation of plate tectonics around the *** further understand the changes that occurred between 3 and 2 Ga,it is necessary to compare rocks,rock associations,tectonics and geochemistry during and between zircon age *** of peak and inter-peak basalts and TTGs needs to be evaluated in terms of geodynamic models that predict the existence of an episodic thermal regime between stagnant-lid and plate tectonic regimes in early planetary evolution.

关键词： Plate tectonics Zircon age peaks Mantle evolution Stagnant lid Continental crust LIP events

An assessment of coal pillar system stability criteria based on a mechanistic evaluation of the interaction between coal pillars and the overburden

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International Journal of Mining Science and Technology 2017年第1期27卷 9-15页

作者： Reed Guy Mctyer kent Frith Russell Mine Advice Pry Ltd NewcastleNSW 2322Australia

Coal pillar design has historically assigned a factor of safety(Fo S) or stability factor(SF) according to their estimated strength and the assumed overburden load acting on them. Acceptable Fo S values have been assigned based on past mining experience or a statistical link between Fo S and probability of failure(Po F). Pillar width-to-height(w/h) ratio has long been established as having a material influence on both pillar strength and its potential failure mode. However, there has been significant disagreement on using both factor of safety(Fo S) and w/h as part of pillar system stability criterion, as compared to using Fo S in isolation. This paper will argue that there are valid technical reasons to bring w/h ratio into system stability criteria(other than its influence on pillar strength), as it is related to the post-failure stiffness of the pillar, as measured in situ, and its interaction with overburden stiffness. When overburden stiffness is also brought into pillar system stability considerations, two issues emerge. The first is the width-todepth(W/D) ratio of the panel and whether it is sub-critical or super-critical from a surface subsidence perspective. The second relates to a re-evaluation of pillar Fo S based on whether the pillar is in an elastic or non-elastic(i.e., post-yield) state in its as-designed condition, as this is relevant to maintaining overburden stiffness at the highest possible level. The significance of the model is the potential to maximise both reserve recovery and mining efficiencies without any discernible increase in geotechnical risk, particularly in thick seams and higher depth of cover mining situations. At a time when mining economics are, at best, marginal, removing potentially unnecessary design conservatism is of interest to all mine operators and is an important topic for discussion amongst the geotechnical community.

关键词： Coa] pillars Stability Overburden Post-failure behaviour Stability criteria

Difference in BOF Slag Splashing in US and China

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Journal of Iron and Steel Research International 2001年第1期8卷 1-5页

作者： CHEN Wei-qing kent Peaslee University of Science and Technology Beijing University of Missouri-Rolla

Some differences in slag splashing between BOF steel works in US and China were investigated. The slag composition,melting point, and mineralogical phases of final slags from both countries were studied. The control o... 详细信息

关键词： slag splashing BOF melting point mineralogical phases superheat

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Measuring user preferences and behaviour in a topographic immersive virtual environment(TopoIVE)of 2D and 3D urban topographic data

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International Journal of Digital Earth 2021年第12期14卷 1835-1867页

作者： Łukasz Halik Alexander J.kent Department of Cartography and Geomatics Adam Mickiewicz UniversityPoznańPoland School of Psychology and Life Sciences Canterbury Christ Church UniversityCanterburyUK

This paper investigates user preferences and behaviour associated with 2D and 3D modes of urban representation within a novel Topographic Immersive Virtual Environment(TopoIVE)created from official 1:10,000 *** participants were divided into two groups:the first were given a navigational task within a simulated city and the second were given the freedom to explore it.A Head-Mounted Display(HMD)Virtual Reality(VR)app allowed participants to switch between 2D and 3D representations of buildings with a remote controller and their use of these modes during the experiment was *** performed mental rotation tests before entering the TopoIVE and were interviewed afterwards about their experiences using the *** results indicate that participants preferred the 3D mode of representation overall,although preference for the 2D mode was slightly higher amongst those undertaking the navigational task,and reveal that different wayfinding solutions were adopted by participants according to their ***,the findings suggest that users exploit different aspects of 2D and 3D modes of visualization in their wayfinding strategy,regardless of their *** potential to combine the functionality of 2D and 3D modes therefore offers substantial opportunities for the development of immersive virtual reality products derived from topographic datasets.

关键词： Virtual reality(VR) immersive virtual environment(IVE) 2D versus 3D wayfinding topographic data

Increased mutant KRAS gene dosage drives pancreatic cancer progression: evidence for wild-type KRAS as a tumor suppressor?

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Hepatobiliary Surgery and Nutrition 2018年第5期7卷 403-405页

作者： Oliver A. kent Princess Margaret Cancer Centre University Health Network Toronto Medical Discovery Tower Toronto Canada

RAS genes are most commonly associated with gain-of function mutations that promote oncogenic behavior. Activating mutations in KRAS occur in 90–95% cases of pancreatic ductal adenocarcinoma (PDAC) a deadly and highly metastatic disease. Currently the fourth leading cause of cancer death in the United States, PDAC presents with a dismal 5-year survival rate of less than 5% (1).

关键词： KRAS dosage cancer

Ophiolites:Identification and tectonic significance in space and time

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Geoscience Frontiers 2023年第6期14卷 380-385页

作者： kent C.Condie Robert J.Stern Department of Earth&Environmental Science New Mexico Institute of Mining and TechnologySocorroNM 87801USA Geosciences Department University of Texas at DallasRichardsonTX 75080USA

Ophiolites are fragments of oceanic lithosphere that are produced at spreading centers at ocean ridges,back arc basins,or forearcs during subduction initiation,and are key indicators of plate *** it is widely agreed that ophiolites are remnants of oceanic crust and associated depleted mantle preserved in orogens,the recognition of ophiolites and their tectonic significance is still a topic of discussion and *** propose that ophiolites can be recognized in the geologic record by some combination of genetically related pillow basalt,layered gabbro,sheeted dykes,podiform chromite,harzburgite or/and *** igneous rocks have either ocean-ridge basalt or immature oceanic arc basalt chemical *** a scoring system of 1–11 for ophiolite confidence level,scores of8 are considered confident,6–8 probable,and900 Ma ophiolites is probably real.

关键词： Ophiolite Plate tectonics Subduction initiation Forearc Ocean ridge Tectonic setting Supercontinent

Greenhouse gases fluxes and soil thermal properties in a pasture in central Missouri

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Journal of Environmental Sciences 2010年第7期22卷 1029-1039页

作者： Nsalambi Vakanda Nkongolo Shane Johnson kent Schmidt Frieda Eivazi Department of Agriculture and Environmental Sciences College of Agriculture and Natural Science Lincoln University Harvard Forest Faculty of Arts and Sciences Harvard University

Fluctuations of greenhouse gases emissions and soil properties occur at short spatial and temporal scales, however, results are often reported for larger scales studies. We monitored CO2, CH4, and N2O fluxes and soil temperature （T）, thermal conductivity （K）, resistivity （R） and thermal diffusivity （D） from 2004 to 2006 in a pasture. Soil air samples for determination of CO2, CH4 and N2O concentrations were collected from static and vented chambers and analyzed within two hours of collection with a gas chromatograph. T, K, R and D were measured in-situ using a KD2 probe. Soil samples were also taken for measurements of soil chemical and physical properties. The pasture acted as a sink in 2004, a source in 2005 and again a sink of CH4 in 2006. CO2 and CH4 were highest, but N2O as well as T, K and D were lowest in 2004. Only K was correlated with C02 in 2004 while T correlated with both N2O （r = 0.76, p = 0.0001） and CO2 （r = 0.88, p = 0.0001） in 2005. In 2006, all gases fluxes were significantly correlated with T, K and R when the data for the entire year were considered. However, an in-depth examination of the data revealed the existence of month-to-month shifts, lack of correlation and differing spatial structures. These results stress the need for further studies on the relationship between soil properties and gases fluxes. K and R offer a promise as potential controlling factors for greenhouse gases fluxes in this pasture.

关键词： greenhouse gases soil thermal properties fluxes

MiRNA as potential biomarkers and therapeutic targets for gastric cancer

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World Journal of Gastroenterology 2014年第30期20卷 10432-10439页

作者： Vivian Yvonne Shin kent-Man Chu Department of Surgery The University of Hong KongQueen Mary Hospital

Gastric cancer is one of the leading causes of cancer mortality in the world. Aberrant expression of microRNAs (miRNAs) is the hallmark of this disease. MiRNAs are endogenous non-coding RNAs that are involved in many biological processes (e.g., cell proliferation, differentiation, apoptosis, invasion and development) through gene repression. Deregulation of miRNA expression in gastric tumors and cancer cell lines have been documented to contribute in tumorigenesis, and the expression signature may correlate with different cancer types and clinicopathological features. Here, we summarized the updated gastric cancer-associated miRNAs and the downstream targets in the process of tumorigenesis. Recently, many researchers make use of the miRNA microarray platform to profile miRNA expression in gastric cancer and correlated with different clinical parameters. Its application on cancer diagnosis, prognosis and predicting treatment response rate are still underway and needs further investigation. Emerging roles of miRNAs with oncogenic or tumor suppressive properties in gastric tumorigenesis were discussed. Epigenetic silencing of miRNA by hypermethylation of promoter CpG island was also observed in gastric cancer. However, detailed mechanisms of how miRNAs regulate gene expression in gastric cancer has not been well studied. In this review, we highlight the up-to-date findings on the deregulated miRNAs in gastric cancer, and the potential use of miRNA in the clinical settings, such as diagnostic/prognostic markers and chemotherapeutic tools.

关键词： MicroRNA Gastric cancer Biomarker Diagnosis Prognosis Clinical application

Predictability of US tornado outbreak seasons using ENSO and northern hemisphere geopotential height variability

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Geoscience Frontiers 2016年第1期7卷 21-31页

作者： kent H.Sparrow Andrew E.Mercer Department of Geosciences Mississippi State University

The predictability of dangerous atmospheric phenomena such as tornado outbreaks has generally been limited to a week or less. However, recent work has demonstrated the importance of the Rossby wavetrain phasing over the United States in establishing outbreak-favorable environments. The predictability of Rossby wavetrain phasing is strongly related to numerous climate-scale interannual variability indices, which are predictable many months in advance. To formalize the relationship between interannual variability indices and seasonal tornado outbreak frequency, indices derived from monthly mean Northern Hemisphere 500-hPa and 1000-hPa geopotential height fields and Ni？o 3.4 indices for ENSO phase were compared to annual tornado outbreak seasonal frequencies. Statistical models predicting seasonal outbreak frequency were established using linear（stepwise multivariate linear regressione SMLR） and nonlinear（support vector regressione SVR） statistical modeling *** stepwise methodology revealed predictors that are important in establishing outbreak-favorable environments at long lead times. Additionally, the results of the statistical modeling revealed that the nonlinear SVR technique reduced root mean square errors produced by the control SMLR technique by 28% and provided more consistent forecasts. A preliminary physical analysis revealed that years with high outbreak frequencies were associated with the presence of 500-mb troughs over the central and western US during the peak of outbreak season, while lower frequencies were consistent with ridging over the US or northwest flow over the Plains. These patterns support the results of the statistical modeling, which demonstrate the utility of geopotential height variability as a predictability measure of outbreak frequency.

关键词： Interannual variability Support vector regression Climate predictability Tornado outbreaks