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Understanding Science Through the Computational Lens

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Journal of Computer Science & Technology 2011年第4期26卷 569-577页

作者： richard m.Karp Department of Electrical Engineering and Computer Sciences University of California

This article explores the changing nature of the interaction between computer science and the natural and social sciences. After briefly tracing the history of scientific computation, the article presents the concept of computational lens, a metaphor for a new relationship that is emerging between the world of computation and the world of the sciences. Our main thesis is that, in many scientific fields, the processes being studied can be viewed as computational in nature, in the sense that the processes perform dynamic transformations on information represented as digital data. Viewing natural or engineered systems through the lens of their computational requirements or capabilities provides new insights and ways of thinking. A number of examples are discussed in support of this thesis. The examples are from various fields, including quantum computing, statistical physics, the World Wide Web and the Internet, mathematics, and computational molecular biology.

关键词： computational process computer science and other sciences computational lens

metamorphic consequences of secular changes in oceanic crust composition and implications for uniformitarianism in the geological record

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Geoscience Frontiers 2018年第4期9卷 1009-1019页

作者： richard m.Palin Brendan Dyck Department of Geology and Geological Engineering Colorado School of Mines Department of Earth Sciences Simon Fraser University

Cooling of the Earth＇s mantle since the meso-Archean is predicted by thermal and petrological models to have induced a secular change in the composition of primary mantle-derived magmas-and thus bulk oceanic crust; in particular, suggesting a decrease in maficity over time. This hypothesis underpins several recent studies that have addressed key geological questions concerning evolving plate tectonic styles, the rates and timing of continental crust formation, comparative planetology, and the emergence of complex life on Earth. major, minor, and trace element geochemical analyses of（meta）mafic rocks preserved in the geological record allows exploration of this theory, although no consensus currently exists about the magnitude of this change and what compositions-if anything-constitute representative examples of Paleo-, meso-, or Neo-Archean primitive oceanic crust. In this work, we review the current state of understanding of this issue, and use phase equilibria to examine the different mineral assemblages and rock types that would form during metamorphism of basalt of varying maficity in subduction zone environments. The presence（or absence） of such metamorphic products in the geological record is often used as evidence for（or against） the operation of modern-day subductiondriven plate tectonics on Earth at particular time periods; however, the control that secular changes in composition have on the stability of mineral assemblages diagnostic of subduction-zone metamorphism weakens such uniformitarianistic approaches. Geodynamic interpretations of the Archean metamorphic rock record must therefore employ a different set of petrological criteria for determining tectonothermal histories than those applied to Proterozoic or Phanerozoic equivalents.

关键词： Archean mantle cooling Oceanic crust Basalt metamorphism Uniformitarianism

What we have learned from randomized trials of prostate cancer screening

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Asian Journal of Andrology 2011年第3期13卷 369-373,510页

作者： richard m Hoffman Anthony Y Smith medicine Service New Mexico VA Health Care System Albuquerque NM 87108 USA Department of medicine University of New Mexico School of Medicine Albuquerque NM 87108 USA Department of Surgery University of New Mexico School of Medicine Albuquerque NM 87108 USA

The introduction of prostate-specific antigen （PSA） for prostate cancer screening in the late 1980s led to an epidemic of prostate cancer, particularly in developed countries. However, the first valid reports from randomized controlled trials on the efficacy of screening were not published until 2009. men in the screening group in the European Randomized Study of Screening for Prostate Cancer were 20% less likely than those in the control group to die from prostate cancer. The absolute difference was only 0.7/1000, implying that over 1400 men needed to be screened to prevent one prostate cancer death. Screening was also associated with a 70% increased risk for being diagnosed with prostate cancer. The American Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial found no survival benefit for screening. Results were not conclusive because a substantial proportion of study subjects had previously undergone PSA testing, over half of the control group had PSA testing, follow-up was relatively short, and fewer than 100 subjects died from prostate cancer. Balancing the potential survival benefit from screening is the risk of overdiagnosis--finding cancers that would not otherwise cause clinical problems^and the risk of treatment complications, including urinary, sexual and bowel dysfunction. Prostate cancer screening efforts would benefit from improved biomarkers, which more readily identify clinically important cancers. Cancer control efforts might also need to include chemoprevention, though currently available agents are controversial. In the meantime, oatients need to be supoorted in achievine informed decisions on whether to be screened for orostate cancer.

关键词： cancer screening prostate-specific antigen prostatic neoplasms randomized controlled trials as topic

Seismic performance of steel mRF building with nonlinear viscous dampers

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Frontiers of Structural and Civil Engineering 2016年第3期10卷 254-271页

作者： Baiping DONG James m. RICLES richard SAUSE ATLSS Engineering Research Center Department of Civil and Environmental Engineering Lehigh University Bethlehem PA 18015 USA

This paper presents an experimental study of the seismic response of a 0.6-scale three-story seismicresistant building structure consisting of a moment resisting frame （mRF） with reduced beam sections （RBS）, and a frame with nonlinear viscous dampers and associated bracing （called the DBF）. The emphasis is on assessing the seismic performance for the design basis earthquake （DBE） and maximum considered earthquake （mCE）. Three mRF designs were studied, with the mRF designed for 100%, 75%, and 60%, respectively, of the required base shear design strength determined according to ASCE 7-10. The DBF with nonlinear viscous dampers was designed to control the lateral drift demands. Earthquake simulations using ensembles of DBE and mCE ground motions were conducted using the real-time hybrid simulation method. The results show the drift demand and damage that occurs in the mRF under seismic loading. Overall, the results show that a high level of seismic performance can be achieved under DBE and mCE ground motions, even for a building structure designed for as little as 60% of the base shear design strength required by ASCE 7-10 for a structure without dampers.

关键词： seismic response steel mRF nonlinear viscous damper design basis earthquake real-time hybrid simulation

The dilemma of the Jiaodong gold deposits: Are they unique?

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Geoscience Frontiers 2014年第2期5卷 139-153页

作者： richard J.Goldfarb m.Santosh U.S.Geological Survey Box 25046 MS 973 Denver Federal Center State Key Laboratory of Geological Processes and mineral Resources School of Earth Sciences and Resources China University of Geosciences Centre for Exploration Targeting School of Earth and Geographical Sciences University of Western Australia Crawley

The ca. 126e120 ma Au deposits of the Jiaodong Peninsula, eastern China, define the country＇s largest gold province with an overall endowment estimated as＆gt;3000 t Au. The vein and disseminated ores are hosted by NE-to NNE-trending brittle normal faults that parallel the margins of ca. 165e150 ma, deeply emplaced, lower crustal melt granites. The deposits are sited along the faults for many tens of kilometers and the larger orebodies are associated with dilatational jogs. Country rocks to the granites are Pre-cambrian high-grade metamorphic rocks located on both sides of a Triassic suture between the North and South China blocks. During early mesozoic convergent deformation, the ore-hosting structures developed as ductile thrust faults that were subsequently reactivated during Early Cretaceous ＂Yan-shanian＂intracontinental extensional deformation and associated gold formation. 〈br〉 Classification of the gold deposits remains problematic. many features resemble those typical of orogenic Au including the linear structural distribution of the deposits, mineralization style, ore and alteration assemblages, and ore fluid chemistry. However, Phanerozoic orogenic Au deposits are formed by prograde metamorphism of accreted oceanic rocks in Cordilleran-style orogens. The Jiaodong de-posits, in contrast, formed within two Precambrian blocks approximately 2 billion years after devolati-lization of the country rocks, and thus require a model that involves alternative fluid and metal sources for the ores. A widespread suite of ca. 130e123 ma granodiorites overlaps temporally with the ores, but shows a poor spatial association with the deposits. Furthermore, the deposit distribution and mineral-ization style is atypical of ores formed from nearby magmas. The ore concentration requires fluid focusing during some type of sub-crustal thermal event, which could be broadly related to a combination of coeval lithospheric thinning, asthenospheric upwelling, paleo-Pacific plate subducti

关键词： Gold Jiaodong North China block Tectonics mineral deposit mode

metamorphism at convergent plate margins:Preface

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Geoscience Frontiers 2022年第2期13卷 351-353页

作者： richard m.Palin Nick m.W.Roberts Department of Earth Sciences University of OxfordOxford OX13ANUnited Kingdom Geochronology and Tracers Facility British Geological SurveyEnvironmental Science CentreNottinghamUnited Kingdom

*** The year 2020 will long be recognised as a period of sadness and frustration for academics worldwide,given the catastrophic impact that the spread of novel coronavirus“2019-nCoV”-or COVID-19-has had on research and teaching activities,as well as in their personal *** Special Issue was designed to represent an avenue for dissemination of many studies presented at the September2019 Geological Society of America session T23.

关键词： teaching America has

Biochar and Compost Increase Crop Yields but the Effect is Short Term on Sandplain Soils of Western Australia

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Pedosphere 2015年第5期25卷 720-728页

作者： David J.m.HALL richard W.BELL Department of Agriculture and Food School of Veterinary and Life Sciences Murdoch University

Sandplain soils on the south coast of Western Australia have low inherent fertility, which is mainly due to poor nutrient retention caused by insufficient clay and organic colloidal material. Previous research has shown the benefits in nutrient levels and retention from adding clay to sandplain soils; however, there is almost no information on the addition of organic amendments. A field experiment was established at the Esperance Downs Research Station, Western Australian, in may 2010, to assess the effects of wheat straw(WS) and chicken manure(Cm) biochars and compost with and without phosphorus(P) addition on soil properties and crop production over five growing seasons. The five seasons alternated between winter and summer crops. The Cm and WS biochar and compost treatments significantly increased crop yields and P uptake in 3, 2 and 1 of the five seasons, respectively. The yield increases(P more than 8%. By the end of the third season, no differences in crop yields were found that could be attributed to the organic amendments. The addition of P increased crop yields in each winter cropping season. Phosphorus addition explained more than 30%of the variation in crop yields. Despite marginal P levels and summer drought conditions, arbuscular mycorrhizal root colonisation was not affected by the organic amendments. There were no significant interactions between the organic amendments and P addition in terms of crop yields, P uptake or P uptake efficiency. We conclude that much of the effect of the organic amendments was due to direct nutrient addition which dissipated over time.

关键词： mycorrhizal root colonisation nutrient retention organic amendments P addition P uptake

Effects of Topography and Land Use Change on Gully Development in Typical mollisol Region of Northeast China

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Chinese Geographical Science 2016年第6期26卷 779-788页

作者： LI Hao richard m CRUSE LIU Xiaobing ZHANG Xingyi Key Laboratory of mollisols Agroecology Northeast Institute of Geography and AgroecologyChinese Academy of SciencesHarbin 150081China University of Chinese Academy of Sciences Beijing 100049China Department of Agronomy lowa State UniversityAmes500011 lowaUSA

Due to high intensity agricultural exploitation since the middle of the 20 th century, farmland gullies have become a pervasive form of water erosion in Northeast China. Yet few researches are concentrated on how topography and land use affect long-term gully development in this region. In this study, gully distribution in a village with an area of 24.2 km^2 in the central mollisols area of Northeast China in different times were compared by Aerial photography(1968), Quickbird image(2009) and field survey, and factors affecting gully development including land use and topography were analyzed. The results showed that the total gully number decreased from 104 to 69, while occupying area rose from 34.8 ha to 78.4 ha from 1968 to 2009. Fundamental gully distribution had been formed by 1968 as most of 2009′s gullies were evolved from 1968′s gullies′ merge and width expansion process, and new gullies those initiated after 1968 occupied only 7% of total gully area in 2009. Gully area increasing ratio in grassland was the highest and that in forestland was the lowest. The threshold catchment area between simple and complex gully development was around 15 ha to 25 ha. This threshold value sets apart catchment areas that will develop simple or complex gullies in areas with similar environmental conditions. Gully control measurements were urgent because if appropriate gully control implements would not be applied, present gully erosion crisis could be doubled within 50 years.

关键词： gully erosion land use topographic threshold mollisols Northeast China

Behavioral differences within and among populations of an African cichlid found in divergent and extreme environments

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Current Zoology 2019年第1期65卷 33-42页

作者： richard C. Oldham Lauren m. Pintor Suzanne m. Gray School of Environment and Natural Resources The Ohio State University Columbus OH 43210 USA

Animals are increasingly faced with human?induced stressors that vary in space and time, thus we can expect populati on-level diverge nee in behaviors that help animals to cope with en vironme ntal change. However, empirical evidenee of behavioral trait divergence across environmental extremes is lacking. We tested for variation in behavioral traits among 2 populations of an African cichlid fish (Pseudocrenilabrus multicolor victoriae Seegers, 1990) that experience extremes of dissolved oxygen (DO) and turbidity and are known to vary in a number of physiological and life history traits associated with these stressors. Using a comm on garden reari ng experime nt, F1 progeny from wild-caught parents originating from a swamp (low DO, clear) and a river (high DO, turbid) were reared in high DO, clear water. Predator simulation assays were conducted to test for (1) variation in boldness, general activity, and foraging activity between populations,(2) differences in correlations betwee n behaviors with in and across populati ons, and (3) repeatability of behaviors. There was strong evide nee for diverge nee betwee n populati ons, with swamp fish being more bold (i.e.z leaving refuge sooner after a simulated predator attack) and active (i.e., spent more time out of refuge) than river fish. Across populations there were positive correlations between foraging activity and both boldness and general activity;however, within populations, there was only a strong positive relationship between foraging activity and boldness in the river population. Here, we have demonstrated that populations that originate from drastically different environments can produce proge ny that exhibit measurable differences in behaviors and their correlated relati on ships eve n whe n reared un der comm on conditions.

关键词： behavioral correlation behavioral syndrome boldness hypoxia pace of life turbidity