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Quantifying relations between altered hydrology and fish community responses for streams in Minnesota

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Ecological processes 2022年第1期11卷 536-560页

作者： Jeffrey R.Ziegeweid gregory D.Johnson Aliesha l.Krall Kara Fitzpatrick Sara B.levin U.S.Geological Survey California Water Science Center6000 J StPlacer HallSacramentoCA 85819USA U.S.Geological Survey Upper Midwest Water Science Center2280 Woodale DrMounds ViewMN 55112USA Minnesota p.llution Control Agency 520 Lafayette RdSt.PaulMN 55155USA Minnesota p.llution Control Agency 7678 College RoadSuite 105BaxterMN 56425USA

Background:Altered hydrology is a stressor on aquatic life,but quantitative relations between specific aspects of streamflow alteration and biological responses have not been developed on a statewide scale in *** sub-sets regression analysis was used to develop.linear regression models that quantify relations among five categories of hydrologic metrics(i.e.,duration,frequency,magnitude,rate-of-change,and timing)computed from streamgage records and six categories of biological metrics(i.e.,composition,habitat,life history,reproductive,tolerance,trophic)computed from fish-community samples,as well as fish-based indices of biotic integrity(FIBI)scores and FIBI scores normalized to an impairment threshold of the corresponding stream class(FIBI_BCG4).Relations between hydrology and fish community responses were examined using three hydrologic datasets that represented periods of record,long-term changes,and short-term changes to flow regimes in streams of ***:Regression models demonstrated significant relations between hydrologic explanatory metrics and fish-based biological response metrics,and the five regression models with the strongest linear relations explained over 70%of the variability in the biological metric using three hydrologic metrics as explanatory ***-based biological metrics demonstrated the strongest linear relations to hydrologic *** most commonly used hydrologic metrics were related to bankfull flows and aspects of flow ***:Final regression models represent paired streamgage records and biological samples throughout the State of Minnesota and encompass differences in stream orders,hydrologic landscape units,and watershed *** methods can support evaluations of stream fish communities and facilitate targeted efforts to improve the health of fish *** also can be ap.lied to locations outside of Minnesota with continuous streamgage data and fish-community sampl

关键词： EflowStats Best subset regression Altered hydrology Fish community Indices of biotic integrity Ecological flows

Near equilibrium dynamics and one-dimensional spatial–temporal structures of p.lar active liquid crystals

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Chinese physics B 2014年第11期23卷 75-100页

作者：杨小刚 M.gregory Forest 王奇 School of Mathematical Sciences Nankai University Department of Mathematics University of North Carolina at Chapel Hill Department of Mathematics Interdisciplinary Mathematics Institute and NanoCenter at USC University of South Carolina Beijing Computational Science Research Center

We systematically explore near equilibrium, flow-driven, and flow-activity coupled dynamics of p.lar active liquid crystals using a continuum model. Firstly, we re-derive the hydrodynamic model to ensure the thermodynamic laws are obeyed and elastic stresses and forces are consistently accounted. We then carry out a linear stability analysis about constant steady states to study near equilibrium dynamics around the steady states, revealing long-wave instability inherent in this model system and how active parameters in the model affect the instability. We then study model predictions for one- dimensional （1D） spatial-temporal structures of active liquid crystals in a channel subject to physical boundary conditions. We discuss the model prediction in two selected regimes, one is the viscous stress dominated regime, also known as the flow-driven regime, while the other is the full regime, in which all active mechanisms are included. In the viscous stress dominated regime, the p.larity vector is driven by the prescribed flow field. Dynamics depend sensitively on the physical boundary condition and the type of the driven flow field. Bulk-dominated temporal periodic states and spatially homogeneous states are possible under weak anchoring conditions while spatially inhomogeneous states exist under strong anchoring conditions. In the full model, flow-orientation interaction generates a host of planar as well as out-of-plane spatial-temporal structures related to the spontaneous flows due to the molecular self-prop.lled motion. These results provide contact with the recent literature on active nematic suspensions. In addition, symmetry breaking pattems emerge as the additional active viscous stress due to the p.larity vector is included in the force balance. The inertia effect is found to limit the long-time survival of spatial structures to those with small wave numbers, i.e., an asymptotic coarsening to long wave structures. A rich set of mechanisms for generating and li

关键词： active liquid crystals active particles spatial-temporal structures spontaneous flows

Vaginal Birth after Cesarean after Zavanelli Maneuver: A Woman’s Right to Choose

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Aggregated seed arrival alters plant diversity in grassland communities

Open Journal of Obstetrics and Gynecology（妇产科期刊） 2024年第7期 1091页

作者： Nicole Jenkins gregory Vurture Jonathan D.Baum

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Journal of plant Ecology 2014年第1期7卷 51-58页

作者： gregory R.Houseman Department of Biological Sciences Wichita State University1845 FairmountWichitaKS 67260USA

Aims Species aggregation is commonly seen in plant communities and may increase diversity by causing intraspecific competition to exceed interspecific *** potential source of this spatial aggregation is seed dispersal but it is unclear to what extent aggregated seed distributions affect plant diversity in real *** a field experiment,I tested whether uniform or aggregated seed arrival alters community structure and whether these effects vary with sowing *** The experiment consisted of two spatial seeding treatments(uniform and aggregated)that were fully crossed with three seed density ***,3×4-m plots were arrayed in a low-diversity grassland located in Kansas,*** plot was divided into fortyeight,0.5×0.5-m *** aggregated seeding treatments,each of the 15 species was sown into three randomly selected patches within the plot(3×15=45).To create a uniform species arrival but control for the seed addition method,all 15 species were sown into 45 individual patches(with three patches remaining unsown)within each *** mass for each species was held constant at the plot scale between uniform or aggregated treatments within a given level of the sowing density *** two growing seasons,plant density was quantified for all sown species in 15 randomly selected patches from each *** Findings I found evidence for shifts in community structure in response to the different spatial seeding *** evenness of added species was higher under aggregated than uniform sowing *** was no detectable effect of aggregated seed sowing on species richness at 3.75 m^(2) ***,when species richness was extrap.lated to larger scales(11.25 m^(2)),aggregated sowing was predicted to have greater richness than uniform *** of seed aggregation on community structure were apparent only at moderate to high sowing rates,yet the latter are within the range of measured seed dispersal in s

关键词： clumped colonization rank-abundance distributions seed dispersal seed sowing

Totally laparoscopic left hepatectomy using the Torsional Ultrasonic Scalp.l

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World Journal of Gastroenterology 2013年第35期19卷 5929-5932页

作者： Georgios C Sotiropoulos paraskevas Stamopoulos petros Charalampoudis Ernesto p Molmenti Athanasios Voutsarakis gregory Kouraklis 2nd Department of propedeutic Surgery University of AthensMedical School Department of Surgery North Shore University Hospital

Minimal invasive techniques have allowed for major surgical *** report our initial experience of performing total laparoscopic left hepatectomy(segmentsⅡ-Ⅳ)with the lotus(laparoscopic operation by torsional ultrasound)Ultrasonic *** perioperative and postoperative courses of the young female patient were uneventful and she is in a good general condition without complaints 18 mo after *** the best of our knowledge,this is the first total laparoscopic hemihepatectomy to be performed in Greece,as well as the first laparoscopic liver resection using lotus shears.

关键词： laparoscopic surgery liver resectionMinimally invasive surgery Hepatectomy Bloodless surgery Ultrasonic Scalp.l Ultrasonic dissector parenchyma transection liver adenoma Focal nodular hyperplasia

The Emeishan large igneous province:A synthesis

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Geoscience Frontiers 2014年第3期5卷 369-394页

作者： J.gregory Shellnutt National Taiwan Normal University Department of Earth Science

The late permian Emeishan large igneous province （El1p） covers -0.3× 10-6 kml of the western margin of the Yangtze Block and Tibetan plateau with displaced, correlative units in northern Vietnam （Song Da zone）. The ElIp is of particular interest because it contains numerous world-class base metal deposits and is contemporaneous with the late Capitanian （-260 Ma） mass extinction. The flood basalts are the signature feature of the ElIp but there are also ultramafic and silicic volcanic rocks and layered mafic- ultramafic and silicic plutonic rocks exposed. The El1p is divided into three nearly concentric zones （i.e. inner, middle and outer） which correspond to progressively thicker crust from the inner to the outer zone. The eruptive age of the ElIp is constrained by geological, p.leomagnetic and geochronological evidence to an interval of 〈3 Ma. The presence of picritic rocks and thick p.les of flood basalts testifies to high temperature thermal regime however there is uncertainty as to whether these magmas were derived from the subcontinental lithospheric mantle or sub-lithospheric mantle （i.e. asthenosphere or mantle plume） sources or both. The range of Sr （Isr ≈ 0.7040-0.7132）, Nd （ENd（t） ≈ -14 tO ＋8）, pb （206-pb/204-pb1 ≈ 17.9-20.6） and Os （Yos ≈ -5 to ＋11） isotope values of the ultramafic and mafic rocks does not permit a conclusive answer to ultimate source origin of the primitive rocks but it is clear that some rocks were affected by crustal contamination and the presence of near-depleted isotope compo- sitions suggests that there is a sub-lithospheric mantle component in the system. The silicic rocks are derived by basaltic magmas/rocks through fractional crystallization or partial melting, crustal melting or by interactions between mafic and crustal melts. The formation of the Fe-Ti-V oxide-ore deposits is probably due to a combination of fractional crystallization of Ti-rich basalt and fluxing of C02-rich fluids whereas the Ni-Cu-（pGE） deposits are related

关键词： late permian Mantle plume large igneous province Flood basalts Mineral deposits Uplift and doming

Thermal and microstructural characterization of a novel ductile cast iron modified by aluminum addition

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International Journal of Minerals,Metallurgy and Materials 2020年第2期27卷 190-199页

作者： Gülsah Aktas Celik Maria-Ioanna TTzini Seyda p.lat SHakan Atapek gregory NHaidemenopoulos Department of Metallurgical and Materials Engineering Kocaeli UniversityKocaeli 41001Turkey laboratory of Materials Department of Mechanical EngineeringUniversity of ThessalyVolos 38334Greece Department of Mechanical Engineering Khalifa University of Science and TechnologyAbu Dhabi 127788UAE

In high-temperature ap.lications,like exhaust manifolds,cast irons with a ferritic matrix are mostly ***,the increasing demand for higher-temperature ap.lications has led manufacturers to use additional expensive materials such as stainless steels and Ni-resist austenitic ductile cast ***,in order to meet the demand while using low-cost materials,new alloys with improved high-temperature strength and oxidation resistance must be *** this study,thermodynamic calculations with Thermo-Calc software were ap.lied to study a novel ductile cast iron with a composition of 3.5wt%C,4wt%Si,1wt%Nb,0‒4wt%*** designed compositions were cast,and thermal analysis and microstructural characterization were performed to validate the *** lowest critical temperature of austenite to pearlite eutectoid transformation,i.e.,A1,was calculated,and the solidification sequence was *** calculations and experimental data revealed the importance of aluminum addition,as the A1 increased by increasing the aluminum content in the alloys,indicating the possibility of utilizing the alloys at higher *** experimental data validated the transformation temperature during solidification and at the solid state and confirmed the equilibrium phases at room temperature as ferrite,graphite,and MC-type carbides.

关键词： ductile cast iron alloy design Thermo-Calc high-temperature material

Beyond the SDG 15.3.1 Good practice Guidance 1.0 using the Google Earth Engine platform: developing a self-adjusting algorithm to detect significant changes in water use efficiency and net primary production

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Big Earth Data 2023年第1期7卷 59-80页

作者： Andrea Markos Neil Sims gregory Giuliani Foundation for the Conservation of the Chiquitano Forest Santa CruzBolivia Bolivian National Academy of Sciences La PazBolivia Centre for Earth Observation Space&AstronomyCSIROClaytonAustralia GEO lDN Initiative Institute for Environmental Sciences EnviroSPACE LabUniversity of GenevaGenevaSwitzerland Institute for Environmental Sciences GRID-GenevaUniversity of GenevaGenevaSwitzerland

Monitoring changes in Annual Net primary productivity(ANpp)is required for reporting on UN Sustainable Development Goal(SDG)Indicator 15.3.1:the proportion of land that is degraded over the total land *** time-series observations of ANpp to derive Water Use Efficiency(WUE;a measure of ANpp per unit of evapotranspiration)can minimize the influence of climate factors on ANpp observations and highlight the influence of non-climatic drivers of degradation such as land use *** the ANpp and WUE time series may be useful for identifying the primary drivers of land degradation,which could be used to support the land Degradation Neutrality objectives of the UN Convention to Combat Desertification(UNCCD).This paper presents an algorithm for the Google Earth Engine(freely and openly available upon request-http://***/10.5281/zenodo.4429773)to calculate and compare ANpp and WUE time series for Santa Cruz,Bolivia,which has recently experienced an intensification in its land *** code builds on the Good practice Guidance document(ver-sion 1)for monitoring SDG Indicator *** use the MODIS 16-day average,250 m resolution to demonstrate that the Enhanced Vegetation Index(EVI)responds faster to changes in water avail-ability than the Normalized Difference Vegetation Index(NDVI).We also consider the relationships between ANpp and *** and concordant trends may highlight good agricultural practices or increased resilience in ecosystem structure and productivity when they are positive or reducing resilience and functional integrity if *** sign and significance of the correlation between ANpp and WUE may also diverge over *** further analysis,it may be possible to interpret this relationship in terms of the drivers of change in plant productivity and ecosystem resilience.

关键词： land degradation land productivity water use efficiency Google Earth Engine MODIS Good practice Guidance SDG 15.3.1

Current treatment for colorectal liver metastases

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World Journal of Gastroenterology 2011年第36期17卷 4067-4075页

作者： Evangelos p Misiakos Nikolaos p Karidis gregory Kouraklis Third Department of Surgery Medical SchoolUniversity of AthensAttikon University HospitalAthens 12462Greece Second propedeutic Department of Surgery Medical SchoolUniversity of AthensGeneral Hospital LaikoAthens 11527Greece

Surgical resection offers the best opportunity for survival in patients with colorectal cancer metastatic to the liver,with five-year survival rates up to 58% in selected ***,only a minority are resectable at the time of *** research in this field aims at increasing the percentage of patients eligible for resection,refining the indications and contraindications for surgery,and improving overall *** use of surgical innovations,such as staged resection,portal vein embolization,and repeat resection has allowed higher resection rates in patients with bilobar *** use of neoadjuvant chemotherapy allows up to 38% of patients previously considered unresectable to be significantly downstaged and eligible for hepatic *** techniques have gained wide acceptance as an adjunct to surgical resection and in the management of patients who are not surgical *** management of colorectal liver metastases requires a multidisciplinary approach,which should be individualized in each case.

关键词： Colorectal liver metastases Multidisciplinary treatment