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A functional tacrolimus-releasing nerve wrap for enhancing nerve regeneration following surgical nerve repair

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Neural Regeneration Research 2025年第1期20卷 291-304页

作者： Simeon C.da.schler Katelyn J.W.So Konstantin Feinberg Marina Manoraj Jenny Cheung Jennifer Zhang Kaveh Mirmoeini JPaul Santerre Tessa Gordon gregory HBorschel SickKids Research Institute Neuroscience and Mental Health ProgramTorontoONCanada Institute of Biomaterials and Biomedical Engineering University of TorontoTorontoONCanada Indiana University School of Medicine IndianapolisINUSA Division of Plastic and Reconstructive Surgery the Hospital for Sick ChildrenTorontoONCanada Translational Biology and Engineering Program Ted Rogers Centre for Heart ResearchInstitute of Biomedical EngineeringFaculty of DentistryUniversity of TorontoTorontoONCanada

Axonal regeneration following surgical nerve repair is slow and often incomplete,resulting in poor functional recovery which sometimes contributes to lifelong ***,there are no Fda.approved therapies available to promote nerve *** accelerates axonal regeneration,but systemic side effects presently outweigh its potential benefits for peripheral nerve *** authors describe herein a biodegrada.le polyurethane-based drug delivery system for the sustained local release of tacrolimus at the nerve repair site,with suitable properties for scalable production and clinical application,aiming to promote nerve regeneration and functional recovery with minimal systemic drug *** is encapsulated into co-axially electrospun polycarbonate-urethane nanofibers to generate an implantable nerve wrap that releases therapeutic doses of bioactive tacrolimus over 31 *** and drug loading are adjustable for applications in small and large caliber nerves,and the wrap degrades within 120 da.s into biocompatible *** released from the nerve wrap promotes axon elongation in vitro and accelerates nerve regeneration and functional recovery in preclinical nerve repair models while off-target systemic drug exposure is reduced by 80%compared with systemic *** its surgical suitability and preclinical efficacy and safety,this system may provide a readily translatable approach to support axonal regeneration and recovery in patients undergoing nerve surgery.

关键词： biodegrada.le local drug delivery nerve injury nerve regeneration nerve wrap tacrolimus

Optical monitoring of particle aggregates

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Journal of Environmental Sciences 2009年第1期21卷 2-7页

作者： John gregory Department of Civil Environmental and Geomatic EngineeringUniversity College London

Methods for monitoring particle aggregation are briefly reviewed. Most of the techniques are based on some form of light scattering and may be greatly dependent on the optical properties of aggregates, which are not generally known. As fractal aggregates grow larger their density can become very low and this has important practical consequences for light scattering. For instance, the scattering coefficient may be much less than for solid objects, which means that the aggregates can appear much smaller than their actual size by a light transmission method. Also, for low-density objects, a high proportion of the scattered light energy is within a small angle of the incident beam, which may also be relevant for measurements with aggregates. Using the ＂turbidity fluctuation＂ technique as an example, it is shown how the apparent size of hydroxide flocs depends mainly on the included impurity particles, rather than the hydroxide precipitate itself. Results using clay suspensions with hydrolyzing coagulants and polymeric floceulants under different string conditions are discussed.

关键词： monitoring method flocculation turbidity fluctuation

Time-first approach for land cover mapping using big Earth observation da.a time-series in a da.a cube-a case study from the Lake Geneva region(Switzerland)

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Big Earth da.a 2024年第3期8卷 435-466页

作者： gregory Giuliani Institute for Environmental Sciences EnviroSPACE labUniversity of GenevaGenevaSwitzerland United Nations Environment Programme Division of Early Warning and AssessmentGenevaSwitzerland

Accurate,consistent,and high-resolution Land Use&Cover(LUC)information is funda.ental for effectively monitoring landscape dynamics and better apprehending drivers,pressures,state,and impacts on land ***,the availability of such national products with high thematic accuracy is still limited and consequently researchers and policymakers are constrained to work with da.a that do not necessarily reflect on-the-ground realities impending to correctly capture details of landscape features as well as limiting the identification and quantification of drivers and rate of ***,we took advantage of the Switzerland’s official LUC statistical sampling survey and dense time-series of Sentinel-2 da.a,combining them with Machine and Deep Learning methods to produce an accurate and high spatial resolution land cover map over the Lake Geneva *** suggest that time-first approach is a valuable alternative to space-first approaches,accounting for the intra-annual variability of classes,hence improving classification *** demonstrate that Deep Learning methods outperform more traditional Machine Learning ones such as Random Forest,providing more accurate predictions with lower *** produced land cover map has a high accuracy,an improved spatial resolution,while at the same time preserving the statistical significance(*** proportion)of the official national *** work paves the way towards the objective to produce a yearly high resolution land cover map of Switzerland and potentially implement a continuous land change monitoring *** further work is required to properly address challenges such as the need for increased temporal resolution for LUC information or the quality of training samples.

关键词： Land cover Sentinel-2 timeseries SITS Arealstatistik

Global weirding at mass extinction horizons

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National Science Review 2024年第1期11卷 10-12页

作者： gregory J.Retallack Department of Earth Sciences University of Oregon

A strong motivation for studying mass extinctions is understanding how current climatic and biodiversity crises will affect creatures living on land such as ourselves. Perhaps the question is: how bad can it get? In that case, terrestrial Permian-Triassic mass extinctions are an irresistible worst-case scenario [1].

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Assessing risks from mining-induced ground movements near gas wells

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International Journal of Mining Science and Technology 2020年第1期30卷 11-16页

作者： Christopher Mark gregory M.Rumbaugh Mine Safety and Health Administration PittsburghPAUSA

The proliferation of unconventional gas well development in the Northern Appalachian coalfields has raised a number of mine safety *** wells,which extract gas from deep shale formations,are characterized by gas volumes and pressures that are significantly higher than those observed at many conventional *** gas is composed largely of methane as well as other *** of planned and actively producing wells penetrate protective coal pillars or barriers within active mine bounda.ies,including chain pillars located between longwall *** released from a well da.aged by mining-induced ground movements could pose a risk to miners by flowing into the mine *** mining-induced ground movements that may cause well da.age include conventional subsidence,non-conventional subsidence(*** plane slip),pillar failure,and floor *** paper describes the known risk factors for each of the four failure *** includes a framework that can guide the risk assessment process when mining takes place near gas or oil wells.

关键词： Gas well Subsidence Coal protection pillar Risk matrix Longwall mining

From common gardens to candida.e genes:an elegant case of homoploid hybrid speciation

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Molecular Plant 2021年第2期14卷 200-201页

作者： gregory L.Owens Department of Biology University of VictoriaVictoriaBCCanada

Homoploid hybrid speciation(HHS),where genetic contributions from two species combine to produce a third species without a change in pioidy,remains an intriguing and enigmatic evolutionary *** studies in the past decade have shown that introgression and admixture between species is common,and yet well documented cases of HHS remain rare(Schumer et al.,2014;Marques et al.,2019).This strikes at a key feature of HHS;it is a far higher bar to prove that hybridization was critical for speciation than it is to show that introgression *** former requires us to know how reproductive isolation(RI)is achieved,identify hybrid ancestry,and definitively link hybrid ancestry with reproductive *** this in mind,the work by Wang et al.(2020)fully documenting a case of HHS is particularly impressive in terms of both the scope and clarity of the results.

关键词： al. combine intro

Introducing RiverProfileApp,a web application for near-global,exploratory,longitudinal river profile analysis

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International Journal of Digital Earth 2022年第1期15卷 679-689页

作者： gregory A.Ruetenik Czech Academy of Sciences Institute of GeophysicsPragueCzech Republic

River profile analysis has been used extensively in the earth sciences. Commonly,exploration of river profiles requires downloading and processing Digital Elevation Models (DEMs) for specific areas,which limits the scope of exploratory analysis. Presented here is a web application designed to analyze river profiles at 90m resolution at a near-global scale. The app allows users to quickly query downstream or upstream from selected points anywhere within ±60 degrees latitude,in order to interactively analyze corresponding river profiles. River profile analysis can be performed in both distance and χ space,where χ is a metric that is proportional to the presumed steady-state shape of the river profile. River locations are based on the HydroSHEDS 90m drainage direction grid,as well as custom computed D8 drainage direction and void-filled SRTM DEMs. RiverProfileApp is open source,and although currently it is designed as an exploratory tool,more functions can be easily added via community contributions and/or from existing toolsets. It is available from ***.

关键词： River profile analysis geomorphology big da.a science communication

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 da.shan gregory J Anderson Iron Metabolism Laboratory The Queensland Institute of Medical ResearchBrisbaneAustralia

The human body requires about 1-2 mg of iron per da. 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 funda.ental da.abases,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 funda.ental 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