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Journal of Bionic Engineering 2009年第3期6卷 239-245页

作者： Mohammad Ismail Talukder pepe Siy gregory Auner Department of Electrical and Computer Engineering Wayne State University

probes are the interface between microsystems and *** ideal interface is one-to-one *** various research groups have been able to establish some sort of interfaces after many years of research,they are very *** are millions in numbers,whereas the prostheses successfully built so far have only a few hundred probes at *** an ef- fective interface is still far *** we have micro-and nano-technologies,we couldn't build a prosthesis with an effective *** reasons behind it are the type of probe being used and the poor design of the *** address this problem,we developed a methodology to design a probe and an array of probes with better resolution and less resistive donut *** methodology helps us to design a probe optimizing all the *** presented our methodology through a design that is capable of 70 μm penetration inside the *** tissue heating by our designed probe is only 0.411 °*** also characterized the donut probe,which could be used by any research group to design a donut probe of their specific need.

关键词： donut probe resolution methodology retina prosthesis probe design

Near equilibrium dynamics and one-dimensional spatial–temporal structures of polar 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 polar 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 polarity 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-propelled 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 polarity 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

Aggregated seed arrival alters plant diversity in grassland communities

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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 extrapolated 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 Scalpel

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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 Scalpel 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, paleomagnetic and geochronological evidence to an interval of 〈3 Ma. The presence of picritic rocks and thick piles 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

peripheral nerve allograft:how innovation has changed surgical practice

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plastic and Aesthetic Research 2022年第1期9卷 154-170页

作者： gregory Buncke The Buncke Clinic San FranciscoCA 94114USA

The landscape of available technology and surgical technique has changed over the last several decades,thus leading to changes in the peripheral nerve repair surgical *** is a common procedure;however,it is well recognized that nerve repair should be performed tensionless,thus preventing the ability to perform direct repair with a nerve ***,nerve gaps were repaired with ***,autograft surgery has been associated with complications such as numbness and chronic pain,which left surgeons searching for *** allografts were first utilized in the 1800s but failed due to the immune *** the modern era,they were again utilized in the 1980s,but did not gain popularity because of the need for the use of *** was evident through the 1990s that continued innovation in peripheral nerve repair was needed,as studies showed that only approximately 50% of patients with nerve gap repair achieved good or excellent *** the 2000s,the advent of an engineered nerve allograft(Avance■Nerve Graft)changed the landscape of peripheral nerve *** clinical evaluation of Avance showed that adequate sensation was able to be achieved in nerve gaps up to 30 mm,providing an alternative to *** engineered nerve allograft use became more conventional,studies showed 87.3% meaningful recovery in nerve gaps up to 50 ***,recent studies have shown that gaps between 50-70 mm have shown 69% meaningful *** technology and surgical technique continue to improve,these results are promising for large nerve gap repair.

关键词： peripheral nerve repair nerve autograft nerve allograft nerve conduit

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

Insights on augmenter of liver regeneration cloning and function

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World Journal of Gastroenterology 2006年第31期12卷 4951-4958页

作者： Elisavet Gatzidou gregory Kouraklis Stamatios Theocharis Department of Forensic Medicine and ToxicologySecond Department of propedeutic Surgery University of AthensMedical SchoolAthensGreece Second Department of propedeutic SurgeryUniversity of Athens Medical SchoolLaikon General HospitalAthensGreece Department of Forensic Medicine and ToxicologyUniversity of Athens Medical SchoolAthensGreece

Hepatic stimulator substance （HSS） has been referred to as a liver-specific but species non-specific growth factor. Gradient purification and sequence analysis of HSS protein indicated that it contained the augmenter of liver regeneration （ALR）, also known as hepatopoietin （HpO）. ALR, acting as a hepatotrophic growth factor, specifically stimulated proliferation of cultured hepatocytes as well as hepatoma cells in vitro, promoted liver regeneration and recovery of damaged hepatocytes and rescued acute hepatic failure in vivo. ALR belongs to the new Erv1/Alr protein family, members of which are found in lower and higher eukaryotes from yeast to man and even in some double-stranded DNA viruses. The present review article focuses on the molecular biology of ALR, examining the ALR gene and its expression from yeast to man and the biological function of ALR protein. ALR protein seems to be non-liver-specific as was previously believed, increasing the necessity to extend research on mammalian ALR protein in different tissues, organs and developmental stages in conditions of normal and abnormal cellular growth.

关键词： Hepatic stimulator substance Augmenter of liver regeneration Liver regeneration Molecular biology

Homogalacturonan MethyI-Esterification and plant Development

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Molecular plant 2009年第5期2卷 851-860页

作者： Sebastian Wolf gregory Mouille Jerome pelloux Heidelberg Institute for plant Science Im Neuenheimer Feld 360 69120 Heidelberg Germany Laboratoire de Biologie Cellulaire Institut Jean-Pierre Bourgin INRA Centre de Versailles-Grignon Route de St Cyr 78026 Versailles France EA3900-BiopI Biologie des plantes et contrble des Insectes ravageurs Universite de Picardie 33 Rue St Leu 80039 Amiens France

The ability of a plant cell to expand is largely defined by the physical constraints imposed by its cell wall. Accordingly, cell wall properties have to be regulated during development. The pectic polysaccharide homogalacturonan is a major component of the plant primary walls. Biosynthesis and in muro modification of homogalacturonan have recently emerged as key determinants of plant development, controlling cell adhesion, organ development, and phyllotactic patterning. This review will focus on recent findings regarding impact of homogalacturonan content and methylesterification status of this polymer on plant life. Demethyl-esterification of homogalacturonan occurs through the action of the ubiquitous enzyme ＇pectin methyl-esterase＇. We here describe various strategies developed by the plant to finely tune the methyl-esterification status of homogalacturonan along key events of the plant lifecycle.

关键词： Carbohydrate metabolism cell walls Arabidopsis pectin.

Change in observed long-term greening across Switzerlandevidence from a three decades NDVI time-series and its relationship with climate and land cover factors

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Big Earth Data 2024年第1期8卷 1-32页

作者： Claire Obuchowicz Charlotte poussin gregory Giuliani Institute for Environmental Sciences EnviroSPACE labUniversity of GenevaGenevaSwitzerland Institute for Environmental Sciences University of GenevaGenevaSwitzerland

Environmental changes are significantly modifying terrestrial vegetation dynamics,with serious consequences on Earth system functioning and provision of ecosystem *** conditions are an essential element underpinning global sustainability frameworks,such as the Sustainable Development Goals(SDGs),requiring effective solutions to assess the impacts of changing land conditions induced by various driving *** the global scale,long-term increase of vegetation greening has been widely reported notably in seasonally snow-covered ecosystems as a response to warming ***,greening trends at the national scale have received less attention,although countries like Switzerland are prone to important changing climate ***,we used a 35-year satellite-derived annual and seasonal time-series of Normalized Difference Vegetation Index(NDVI)to assess vegetation greenness evolution at different spatial and temporal scales across Switzerland and related them to temperature,precipitation,and land cover to investigate possible responses of changing climatic *** indicate that there is a statistically significant greening trend at the national scale with an NDVI mean increasing slope of 0.6%/year for the 61%significant pixels across *** particular,the seasonal mean NDVI shows an important break for winter,autumn and spring seasons starting from 2010,potentially indicating a critical point of changing land *** biogeographical scale,we observed an apparent clustering(Jura-plateau;Northern-Southern Alps;Eastern-Western Alps)related to landscape characteristics,while forested land cover classes are more responsive to NDVI ***,the NDVI values are mostly a function of temperature at elevations below the tree line rather than *** findings suggest that multi-annual and seasonal NDVI can be a valuable indicator to monitor vegetation conditions at different scales and can provide complementary observati

关键词： Landsat climate land cover NDVI anomaly