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Liver-gut axis in the regulation of iron homeostasis

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World Journal of Gastroenterology 2007年第35期13卷 4737-4745页

作者： Deepak Darshan gregory J Anderson Iron Metabolism Laboratory The Queensland Institute of Medical ResearchBrisbaneAustralia

The human body requires about 1-2 mg of iron per day for its normal functioning, and dietary iron is the only source for this essential metal. Since humans do not possess a mechanism for the active excretion of iron, the amount of iron in the body is determined by the amount absorbed across the proximal small intestine and, consequently, intestinal iron absorption is a highly regulated process. In recent years, the liver has emerged as a central regulator of both iron absorption and iron release from other tissues. It achieves this by secreting a peptide hormone called hepcidin that acts on the small intestinal epithelium and other cells to limit iron delivery to the plasma. Hepcidin itself is regulated in response to various systemic stimuli including variations in body iron stores, the rate of erythropoiesis, inflammation and hypoxia, the same stimuli that have been known for many years to modulate iron absorption. This review will summarize recent findings on the role played by the liver and hepcidin in the regulation of body iron absorption.

关键词： Iron Homeostasis Intestinal iron absorption Liver Hepcidin

Cybermaterials: materials by design and accelerated insertion of materials

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npj Computational Materials 2016年第1期2卷 233-246页

作者： Wei Xiong gregory B Olson Department of Materials Science and Engineering Northwestern UniversityEvanstonILUSA QuesTek Innovations LLC EvanstonILUSA

Cybermaterials innovation entails an integration of Materials by Design and accelerated insertion of materials(AIM),which transfers studio ideation into industrial *** assembling a hierarchical architecture of integrated computational materials design(ICMD)based on materials genomic fundamental databases,the ICMD mechanistic design models accelerate *** here review progress in the development of linkage models of the process-structure–property-performance paradigm,as well as related design accelerating *** the materials development capability based on phase-level structural control requires more fundamental investment at the level of the Materials Genome,with focus on improving applicable parametric design models and constructing high-quality *** opportunities in materials genomic research serving both Materials by Design and AIM are addressed.

关键词： insertion linkage constructing

Light Hadron Masses in Quantum Chromodynamics with Valence Wilson Quarks at β=6.25 from a Parallel PC Cluster

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Chinese Physics Letters 2002年第5期19卷 636-639页

作者：梅仲豪 EricB.gregory DepartmentofPhysics ZhongshanUniversityGuangzhou510275

We present the results for π, ρ, proton and Δ masses from our recently built Pentium cluster and compare with the quenched Wilson fermion data presented by MILC and GF11 collaborations [***.B (***.) 60A(1998)3, Nucl. Phys. B 430(1994)179] at β = 6/g2=5.7 and 5.85 on the 83×32 lattice. New data are shown at β=6.25 on the 123×36 and 163×32 lattices. Such a large β value is useful for extrapolating the lattice results to the continuum limit. The smearing technique is systematically investigated and can greatly improve the spectrum data.

关键词： Quantum theory

The Methodology of Probe Design with Better Resolution and Less Resistive Donut Probe to Achieve the Best Performance

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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

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