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Impacts of Systematic Precipitation Bias on Simulations of Water and Energy Balances in Northwest America

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Advances in Atmospheric Sciences 2007年第5期24卷 739-749页

作者： Youlong XIA 徐国强 Atmospheric and Oceanic Science Program and NOAA Geophysical Fluid Dynamics Laboratory Princeton University Princeton New Jersey USA State Key Laboratory of Severe Weather Chinese Academy of Meteorological Sciences China Meteorological Administration Beijing 100081

At high latitudes and in mountainous areas, evaluation and validation of water and energy flux simu-lations are greatly affected by systematic precipitation errors. These errors mainly come from topographic effects and undercatch of precipitation gauges. In this study, the Land Dynamics （LAD） land surface model is used to investigate impacts of systematic precipitation bias from topography and wind-blowing on water and energy flux simulation in Northwest America. The results show that topographic and wind adjustment reduced bias of streamflow simulations when compared with observed streamflow at 14 basins. These systematic biases resulted in a -50%-100% bias for runoff simulations, a -20%-20% bias for evapotranspiration, and a -40%-40% bias for sensible heat flux, subject to different locations and adjustments, when compared with the control run. Uncertain gauge adjustment leads to a 25% uncertainty for precipitation, a 20% 100% uncertainty for runoff simulation, a less-than-10% uncertainty for evapotranspiration, and a less-than-20% uncertainty for sensible heat flux.

关键词： LaD model bias adjustment water and energy balance Northwest America

Beyond tumorigenesis: cancer stem cells in metastasis

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Cell Research 2007年第1期17卷 3-14页

作者： Benjamin Tiede JoanMassagué Department of Molecular Biology Princeton University Washington Road PrincetonNJ 08544USA Cancer Biology and Genetics Program and Howard Hughes Medical Institute Memorial Sloan-Kettering Cancer CenterNew YorkNY 10021USA

The importance of cancer stem cells (CSCs) in tumor-initiation has been firmly established in leukemia and recentlyreported for a variety of solid ***,the role of CSCs in multistage cancer progression,particularly withrespect to metastasis,has not been *** metastasis requires the seeding and successful colonization ofspecialized CSCs at distant *** biology of normal stein cells and CSCs share remarkable similarities and mayhave important implications when applied to the study of cancer ***,overlapping sets of moleculesand pathways have recently been identified to regulate both stem cell migration and cancer *** moleculesconstitute a complex network of cellular interactions that facilitate both the initiation of the pre-metastasis niche by theprimary tumor and the formation of a nurturing organ microenvironment for migrating *** this review,we surveyedthe recent advances in this dynamic field and propose a unified model of cancer progression in which CSCs assume acentral role in both tumorigenesis and *** understanding of CSCs as a fundamental component of themetastatic cascade will lead to novel therapeutic strategies against metastatic cancer.

关键词： stem cells cancer stem cells metastasis metastasis roche mouse model

Characterization of intestinal microbiota and fecal cortisol,T3,and IgA in forest musk deer(Moschus berezovskii)from birth to weaning

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Integrative Zoology 2021年第3期16卷 300-312页

作者： Yimeng LI Tianxiang ZHANG Minghui SHI Baofeng ZHANG Xin HU Shanghua XU Jianhong DING Shuqiang LIU Defu HU Daniel RUBENSTEIN School of Ecology and Nature Conservation Beijing Forestry UniversityBeijingChina Department of Ecology and Evolutionary Biology Princeton UniversityPrincetonNew JerseyUSA Beijing Key Laboratory of Captive Wildlife Technology Beijing ZooBeijingChina

Analysis of the intestinal microbiota and physiological parameters in mammalian infancy can reveal health *** this study,we used a combination of molecular and immunochemical approaches to assess fecal microbiota as well as Cortisol(Cor),Triiodothyronine(T3),and immunoglobulin A(IgA)levels of young forest musk deer(FMD),from birth to one month after weaning(7 days of age–110 days of age).During development as the diet of FMD changes from consuming milk to eating plants,the richness and diversity of intestinal microbiota of young FMD increased *** levels remained unchanged throughout early development while significantly increased after weaning,T3 and IgA initially were derived from milk during lactation,significantly decreased after *** network analysis showed that the community of food-oriented microbes were highly structured and that many genera were ***,this study provides scientific insights into effective management strategies for the protection of FMD population.

关键词： forest musk deer intestinal microbiota weaning

Skill-assessments of statistical and Ensemble Kalman Filter data assimilative analyses using surface and deep observations in the Gulf of Mexico

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Frontiers of Earth Science 2013年第3期7卷 271-281页

作者： Zhibin SUN Lie-Yauw OEY Yi-Hui ZHOU universities Space Research Association Columbia MD 21044 USA princeton university AOS Sayre Hall Forrestal Campus Princeton NJ 08544 USA Department of Biostatistics University of North Carolina Chapel Hill NC 27599 USA

A new data assimilation algorithm （Quasi- EnKF） in ocean modeling, based on the Ensemble Kalman Filter scheme, is proposed in this paper. This algorithm assimilates not only surface measurements （sea surface height）, but also deep （-2000 m） temperature observations from the Gulf of Mexico into regional ocean models. With the use of the princeton Ocean Model （POM）, integrated for approximately two years by assimilating both surface and deep observations, this new algorithm was compared to an existing assimilation algorithm （Mellor-Ezer Scheme） at different resolutions. The results show that, by comparing the observations, the new algorithm out-performs the existing one.

关键词： data assimilation deep observation Gulf of Mexico

Optimization Landscape of Quantum Control Systems

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Complex System Modeling and Simulation 2021年第2期1卷 77-90页

作者： Xiaozhen Ge Rebing Wu Herschel Rabitz Department of Automation Tsinghua UniversityBeijing 100084China Department of Chemistry Princeton UniversityPrincetonNJ 08544USA.

Optimization is ubiquitous in the control of quantum dynamics in atomic,molecular,and optical *** ease or difficulty of finding control solutions,which is practically crucial for developing quantum technologies,is highly dependent on the geometry of the underlying optimization *** this review,we give an introduction to the basic concepts in the theory of quantum optimal control landscapes,and their trap-free critical topology under two fundamental ***,the effects of various factors on the search effort are discussed,including control constraints,singularities,saddles,noises,and non-topological features of the ***,we review recent experimental advances in the control of molecular and spin *** results provide an overall understanding of the optimization complexity of quantum control dynamics,which may help to develop more efficient optimization algorithms for quantum control systems,and as a promising extension,the training processes in quantum machine learning.

关键词： quantum control optimization landscape critical manifold

Systematic Hydrological Evaluation of the Noah-MP Land Surface Model over China

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Advances in Atmospheric Sciences 2019年第11期36卷 1171-1187,I0001,I0002,I0003,I0004,I0005页

作者： Jingjing LIANG Zongliang YANG Peirong LIN Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Jackson School of Geosciences University of Texas at Austin Austin TX 78712 USA Department of Civil and Environmental Engineering Princeton University Princeton NJ 08540 USA

We evaluate water budget components-namely,soil moisture,runoff,evapotranspiration,and terrestrial water storage (TWS)-simulated by the Noah land surface model with multi-parameterization options (Noah-MP) in China,a large geographic domain challenging for hydrological modeling due to poor observational data and a lack of one single parameterization that can fit for complex hydrological *** comparing the model simulations with multi-source reference data,we show that Noah-MP can generally reproduce the overall spatiotemporal patterns of runoff and evapotranspiration over six major river basins,with the annual correlation coefficients generally greater than 0.8 and the Nash-Sutcliffe model efficiency coefficient exceeding *** the six basins evaluated,the best model performance is seen over the Huaihe River *** temporal trend of the modeled TWS anomalies agrees well with GRACE (Gravity Recovery and Climate Experiment) observations,capturing major flood and drought events in different *** with 12 selected physical parameterization options show that the runoff parameterization has a stronger impact on the simulated soil moisture-runoff-evapotranspiration relationships than the soil moisture factor for stomatal resistance schemes,a result consistent with previous ***,Noah-MP driven by GLDAS forcing simulates the hydrological variables well,except for the Songliao basin in northeastern China,likely because this is a transitional region with extensive freeze-thaw activity,while representations of human activities may also help improve the model performance.

关键词： hydrological evaluation Noah-MP multi-parameterization China

Effects of holistic grazing management on milk production,weight gain,and visitation to grazing areas by livestock and wildlife in Laikipia County,Kenya

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Ecological Processes 2016年第1期5卷 216-227页

作者： Priscilla K.Lalampaa Oliver V.Wasonga Daniel I.Rubenstein Jesse T.Njoka Faculty of Agriculture Department of Land Resource Management and Agricultural TechnologyUniversity of NairobiP.O.Box 29053-00625NairobiKenya princeton university PrincetonNJ 08544-2016USA

Background:Grazing is an important management tool for maintaining healthy ecosystems and improving rangelands ***,its effectiveness for this purpose is dependent on timing and frequency of grazing,as well as the type of *** the effects of grazing management on rangeland ecosystems is critical in ensuring sustainable use of grazing resources and enhanced livestock *** study assessed the effects of holistic grazing on animal productivity and range use pattern in Laikipia County of ***:The results revealed that the average milk yields(106±20.1)of animals in holistic grazing areas(HGA)were significantly(p<0.05)higher than those in traditional grazing areas(TGA)(101±20.1).Weight gain of animals in HGA was significantly(0.13±0.01)higher as compared to those in TGA(0.07±0.01).The number of livestock grazing was significantly(p<0.05)higher in HGA(74±10%)than those in TGA(57±10%).In addition,the number of wildlife grazing was significantly(p<0.05)higher in HGA(74±18%)than in TGA(32±18%).Conclusions:The results indicate that holistic grazing management has the potential to improve animal performance,as well as condition of range areas as evident in the preference shown by frequent visits to HGA by both livestock and wildlife.

关键词： Camera traps Continuous grazing Animal performance Rest periods Wildlife visits

The Application of Flux-Form Semi-Lagrangian Transport Scheme in a Spectral Atmosphere Model

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Advances in Atmospheric Sciences 2013年第1期30卷 89-100页

作者：王晓聪刘屹岷吴国雄 Shian-Jiann LIN 包庆 State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric PhysicsChinese Academy of Sciences university of Chinese Academy of Sciences NOAA/Geophysical Fluid Dynamics Laboratory Princeton UniversityPrincetonNew Jersey

A flux-form semi-Lagrangian transport scheme （FFSL） was implemented in a spectral atmospheric GCM developed and used at IAP/LASG. Idealized numerical experiments show that the scheme is good at shape preserving with less dissipation and dispersion, in comparison with other conventional schemes, hnportantly, FFSL can automatically maintain the positive definition of the transported tracers, which was an underlying problem in the previous spectral composite method （SCM）. To comprehensively investigate the impact of FFSL on GCM results, we conducted sensitive experiments. Three main improvements resulted： first, rainfall simulation in both distribution and intensity was notably improved, which led to an improvement in precipitation frequency. Second, the dry bias in the lower troposphere was significantly reduced compared with SCM simulations. Third, according to the Taylor diagram, the FFSL scheme yields simulations that are superior to those using the SCM： a higher correlation between model output and observation data was achieved with the FFSL scheme, especially for humidity in lower troposphere. However, the moist bias in the middle and upper troposphere was more pronounced with the FFSL scheme. This bias led to an over-simulation of precipitable water in comparison with reanalysis data. Possible explanations, as well as solutions, are discussed herein.

关键词： advection precipitation spectral composite method flux-form semi-Lagrangian Spectral Atmospheric Model of the IAP/LASG (SAMIL)

Differential effects of short term winter thermal stress on diapausing tiger swallowtail butterflies （Papilio spp.）

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Insect Science 2012年第3期19卷 277-285页

作者： J. Mark Scriber Emily Maher Matthew L. Aardema Department of Entomology Michigan State University East Lansing MI McGuire Center for Lepidoptera and Biodiversity Florida Museum of Natural History University of Florida Gainesville FL Department of Ecology and Evolutionary Biology Princeton University Princeton N J USA

It is generally thought that insects inhabiting lower latitudes are more severely impacted by changes in their thermal environment than are high latitude species. This is attributed to the wider range of temperatures to which high-latitude species are exposed. By contrast, low-latitude species have typically evolved in more thermally stable environments with a narrower range of temperature variation. However, deviation from this pattern can occur and here we report that under variable winter conditions a higher latitude species may be more sensitive to thermal variation than its lower latitude sister species. Using split broods, we examined the survival and adult emergence success of diapausing pupae of Papilio canadensis and P. glaucus, as well as a unique, recombinant hybrid population （＂late-flight＂） to short periods of mid-winter cold and heat stress. Our results indicate that the higher latitude, univoltine populations （P. canadensis and late-flights） exhibit lower pupal survival than the lower latitude, facultative diapauser （P. glaucus） for all mid-winter thermal stress treatments, both high and low. Size differences alone do not appear to account for the observed differences in survival or metabolic costs in these three pheno- types, as late-flight individuals are similar in size to R glaucus. We attribute the observed differences in survival and weight loss to potential metabolic differences and variation in the intensity of diapause, in addition to divergent adaptation to winter precipitation levels （e.g. snow cover） and the influences this may have on microhabitat temperature moderation.

关键词： climate change developmental threshold incipient hybrid species metabolic cost Papilionidae post-diapause delays thermal stress