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Redox Changes during the Legume-Rhizobium Symbiosis

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Molecular Plant 2009年第3期2卷 370-377页

作者： christine Chang Isabelle Damiani Alain Puppo Pierre Frendo UMR INRA-Université de Nice-Sophia Antipolis-CNRS 'Interactions Biotiques et Santé Végétale' 400 Route des Chappes BP167 06903 Sophia Antipolis CedexFrance

Reactive Oxygen Species （ROS） are continuously produced as a result of aerobic metabolism or in response to biotic and abiotic stresses. ROS are not only toxic by-products of aerobic metabolism, but are also signaling molecules involved in plant growth and environmental adaptation. Antioxidants can protect the cell from oxidative damage by scavenging the ROS. Thus, they play an important role in optimizing cell function by regulating cellular redox state and modifying gene expression. This article aims to review recent studies highlighting the role of redox signals in establishing and maintaining symbiosis between rhizobia and legumes.

关键词： Oxidative and photo-oxidative stress cell differentiation/specialization gene regulation symbiosis legume

Using the USLE: Chances, challenges and limitations of soil erosion modelling

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International Soil and Water Conservation Research 2019年第3期7卷 203-225页

作者： christine Alewell Pasquale Borrelli Katrin Meusburger Panos Panagos Environmental Geosciences University of BaselSwitzerland Swiss Federal Institute for Forest Snow and Landscape ResearchBirmensdorfSwitzerland European Commission Joint Research CenterIspraItaly

To give soils and soil degradation,which are among the most crucial threats to ecosystem stability,social and political visibility,small and large scale modelling and mapping of soil erosion is *** most widely used approaches during an 80year history of erosion modelling are Universal Soil Loss Equation (USLE)-type based algorithms which have been applied in 109 *** soil erosion by water (excluding gully erosion and land sliding),we start this review with a statistical evaluation of nearly 2,000 publications).We discuss model developments which use USLE-type equations as basis or side modules,but we also address recent development of the single USLE parameters (R,K,LS,C,P).Importance,aim and limitations of model validation as well as a comparison of USLE-type models with other erosion assessment tools are *** comparisons demonstrate that the application of process-based physical models (e.g.,WEPP or PESERA) does not necessarily result in lower uncertainties compared to more simple structured empirical models such as USLE-type *** identified four key areas for future research:(i) overcoming the principally different nature of modelled (gross) versus measured (net) erosion rates,in coupling on-site erosion risk to runoff patterns,and depositional regime,(ii) using the recent increase in spatial resolution of remote sensing data to develop process based models for large scale applications,(iii) strengthen and extend measurement and monitoring programs to build up validation data sets,and (iv) rigorous uncertainty assessment and the application of objective evaluation criteria to soil erosion modelling.

关键词： Universal soil loss equation RUSLE CSLE Soil redistribution Soil degradation Water erosion Model Review

Genetic evaluation and testing for hereditary forms of cancer in the era of next-generation sequencing

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Cancer Biology & Medicine 2016年第1期13卷 55-67页

作者： christine Stanislaw Yuan Xue William R.Wilcox Department of Human Genetics Emory University Atlanta GA 30322 USA Fulgent Diagnostics Temple City CA 92780USA

The introduction of next-generation sequencing(NGS) technology in testing for hereditary cancer susceptibility allows testing of multiple cancer susceptibility genes simultaneously. While there are many potential benefits to utilizing this technology in the hereditary cancer clinic, including efficiency of time and cost, there are also important limitations that must be considered. The best panel for the given clinical situation should be selected to minimize the number of variants of unknown significance. The inclusion in panels of low penetrance or newly identified genes without specific actionability can be problematic for *** counselors are an essential part of the hereditary cancer risk assessment team, helping the medical team select the most appropriate test and interpret the often complex results. Genetic counselors obtain an extended family history, counsel patients on the available tests and the potential implications of results for themselves and their family members(pre-test counseling), explain to patients the implications of the test results(post-test counseling), and assist in testing family members at risk.

关键词： Genetic counseling genetic testing informed consent high-throughput nucleotide sequencing neoplastic syndromes hereditary

Egg CD9 protein tides correlated with sperm oscillations tune the gamete fusion ability in mammal

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Journal of Molecular Cell Biology 2018年第6期10卷 494-502页

作者： Benjamin Ravaux Sophie Favier Eric Perez and christine Gourier Laboratoire de Physique Statistique Ecole Normale Superieure/PSL Research UniversityUPMC Univ Paris 06Universite Paris DiderotCNRS75005 ParisFrance

Mammalian fertilization involves membrane events-adhesion,fusion,sperm engulfment,membrane block to polyspermy-whose causes remain largely ***,specific oscillations of the sperm in contact with the egg were shown to be necessary for *** a microfluidic chip to impose the venue for the encounter of two gametes allowed real-time observation of the membrane remodelling occurring at the sperm/egg *** spatiotemporal mapping of egg CD9 revealed that this protein concentrates at the egg/sperm interface as a result of sperm oscillations,until a CDg-rich platform is nucleated on which fusion immediately takes *** 2-5 min after fusion,most of the CD9 leaves the egg for the external aqueous *** an egg membrane wave engulfs the sperm head in^25 *** results show that sperm oscillations initiate the CD9 recruitment that causes gamete fusion after which CD9 and associated proteins leave the membrane in a process likely to contribute to block *** highlight that the gamete fusion story in mammals is an unexpected interplay between mechanical constraints and proteins.

关键词： mammalian fertilization membrane dynamics real-time imaging CDg sperm oscillations gamete fusion

Effects of mountain pine beetle-killed forests on source water contributions to streamflow in headwater streams of the Colorado Rocky Mountains

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Frontiers of Earth Science 2017年第3期11卷 496-504页

作者： christine E. WEHNER John D. STEDNICK Watershed Science Program College of Natural Resources Colorado State University Fort Collins CO 80523-1472 USA

Natural or human-influenced disturbances are important to the health and diversity of forests, which in turn, are important to the water quantity and quality exported from a catchment. However, human-induced disturbances （prescribed fire and harvesting） have been decreasing, and natural disturbances （fires and insects） have been increasing in frequency and severity. One such natural disturbance is the mountain pine beetle （MPB）, （Denclroctonus ponderosae） an endemic species. A recent epidemic resulted in the mortality of millions of hectares of lodgepole pine （Pinus contorta） forests in Colorado, USA. Beetle-induced tree mortality brings about changes to the hydrologic cycle, including decreased transpiration and interception with the loss of canopy cover. This study examined the effect of the mountain pine beetle kill on source water contributions to streamflow in snowmelt- dominated headwater catchments using stable isotopes （2H and ~80） as tracers. Study catchments with varying level of beetle-killed forest area （6% to 97%） were sampled for groundwater, surface water, and precipitation. Streams were sampled to assess whether beetle-killed forests have altered source water contributions to streamflow. Ground- water contributions increased with increasing beetle-killed forest area （p = 0.008）. Both rain and snow contributions were negatively correlated with beetle-killed forest area （p = 0.035 and p = 0.011, respectively）. As the beetle-killed forest area increases, so does fractional groundwater contribution to streamflow.

关键词： mountain pine beetle isotope tracers stream-flow generation headwaters

The role of retinoic acid in the commitment to meiosis

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Asian Journal of Andrology 2021年第6期23卷 549-554页

作者： Rachel L Gewiss M christine Schleif Michael D Griswold School of Molecular Biosciences and Center for Reproductive Biology Washington State UniversityPullmanWA 99164USA

Male meiosis is a complex process whereby spermatocytes undergo cell division to form haploid *** review focuses on the role of retinoic acid(RA)in meiosis,as well as several processes regulated by RA before cell entry into meiosis that are critical for proper meiotic entry and ***,we discuss RA metabolism in the testis as well as the roles of stimulated by retinoic acid gene 8(STRA8)and MEIOSIN,which are responsive to RA and are critical for *** assert that transcriptional regulation in the spermatogonia is critical for successful meiosis.

关键词： meiosis retinoic acid spermatogenesis testis

Comparison between the Chinese EIA Guidelines for Air Dispersion Modelling and the Advanced Air Dispersion Model ADMS

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Chinese Journal of Population,Resources and Environment 2005年第4期3卷 15-19页

作者： David Carruthers christine McHugh Cambridge Environmental Research Consultants (CERC) 3 King's Parade Cambridge CB2 1SJ U.K.Cambridge Environmental Research Consultants (CERC) 3 King's Parade Cambridge CB2 1SJ U.K.

This paper makes comparisons between Chinese Environmental Impact Assessment (EIA) Guidelines for Air dispersion modelling and the advanced air dispersion model ADMS. Since 2001 the ADMS model has been the first and only foreign model that has been approved by the Appraisal Center for Environment and Engineering (ACEE) to be used in EIA projects in China (http://***-eia. com/inden_content/rjrz/ rjrz_ADMS/htm). In the paper the following sections provide brief descriptions of the main features of the Chinese Guidelines for Air Dispersion (Section 2) and ADMS (Section 3); Section 4 provides a comparison of the two modelling methods for some simple cases and conclusions and discussion are given in Section 5.

关键词： ADMS EIA guideline Chinese Guideline Air Dispersion Model

Timescales of interface-coupled dissolution-precipitation reactions oncarbonates

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Geoscience Frontiers 2019年第1期10卷 17-27页

作者： Francois Renard Anja Royne christine V.Putnis The Njord Centre Physics of Geological Processes Departments of Geoscience and Physics University of Oslo Univ. Grenoble Alpes Univ. Savoie Mont Blanc CNRS Institut für Mineralogie University of Münster The Institute for Geoscience Research (TIGeR) Department of Chemistry Curtin University

In the Earth's upper crust, where aqueous fluids can circulate freely, most mineral transformations are controlled by the coupling between the dissolution of a mineral that releases chemical species into the fluid and precipitation of new minerals that contain some of the released species in their crystal structure, the coupled process being driven by a reduction of the total free-energy of the system. Such coupled dissolution-precipitation processes occur at the fluid-mineral interface where the chemical gradients are highest and heterogeneous nucleation can be promoted, therefore controlling the growth kinetics of the new minerals. Time-lapse nanoscale imaging using Atomic Force Microscopy(AFM) can monitor the whole coupled process under in situ conditions and allow identifying the time scales involved and the controlling parameters. We have performed a series of experiments on carbonate minerals(calcite, siderite, dolomite and magnesite) where dissolution of the carbonate and precipitation of a new mineral was imaged and followed through time. In the presence of various species in the reacting fluid(e. g. antimony, selenium, arsenic, phosphate), the calcium released during calcite dissolution binds with these species to form new minerals that sequester these hazardous species in the form of a stable solid phase. For siderite, the coupling involves the release of Fe^(2+) ions that subsequently become oxidized and then precipitate in the form of FeIIIoxyhydroxides. For dolomite and magnesite,dissolution in the presence of pure water(undersaturated with any possible phase) results in the immediate precipitation of hydrated Mg-carbonate phases. In all these systems, dissolution and precipitation are coupled and occur directly in a boundary layer at the carbonate surface. Scaling arguments demonstrate that the thickness of this boundary layer is controlled by the rate of carbonate dissolution,the equilibrium concentration of the precipitates and the kinetics of diffus

关键词： Carbonates Atomic force microscopy Dissolution Precipitation Boundary layer Replacement

Growth differentiation factor 6,a repressive target of EZH2,promotes the commitment of human embryonic stem cells to mesenchymal stem cells

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Bone Research 2020年第4期8卷 439-446页

作者： Pend Deng Yongxin Yu christine Hong Cun-Yu Wang Laboratory of Molecular Signaling Division of Oral Biology and MedicineSchool of DentistryUniversity of California Los AngelesLos AngelesCA 90095USA Section of Orthodontics Division of Growth and DevelopmentSchool of DentistryUniversity of California Los AngelesLos AngelesCA 90095USA Jonsson Comprehensive Cancer Center Broad Stem Cell Research Institute and Department of BioengineeringHenry Samueli School of Engineering and Applied ScienceUniversity of California Los AngelesLos AngelesCA 90095USA

Mesenchymal stem cells(MSCs)derived from human embryonic stem cells(hESCs)have significant potential for cell-mediated bone *** recent study revealed that inhibiting the epigenetic regulator EZH2 plays a key role in promoting the mesodermal differentiation of *** this study,an epigenome-wide analysis of hESCs and MSCs revealed that growth differentiation factor 6(GDF6),which is involved in bone formation,was the most upregulated gene associated with MSCs compared to ***,we identified GDF6 as a repressive target of EZH2 and found that ectopic GDF6 selectively promoted hESC differentiation towards the mesodermal lineage and enriched the MSC *** results provide molecular insights governing the mesenchymal commitment of hESCs and identify an inducing factor that offers strong promise for the future of regenerative medicine.

关键词： EZH2 mesenchymal inhibiting