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International Journal of Sediment Research 2022年第1期37卷 14-25页

作者： Salman Saki grant besse Peng Yin Daniel Gang Donald Hayes Department of Civil Engineering University of Louisiana at Lafayette University of Texas at San Antonio U.S.Army Engineer Research and Development Center (ERDC)

Coastal Louisiana has the nation’s most fragile and valuable wetlands,whose loss represents 80% of the total losses in the United *** severely restricted mobility of conventional shoreline protection structures makes them impossible to be *** Wave Suppression and Sediment Collection(WSSC) system is a novel technology of high mobility and compatible with existing shoreline protection *** laboratory studies on WSSC showed great potential for wave reduction and sediment *** current study aimed to optimize the design parameters of WSSC using a validated computational model.A computational fluid dynamics (CFD) model was developed and validated using experimental data from the previous laboratory ***,a parametric analysis was conducted with a focus on the performance optimization of wave reduction and sediment collection with respect to pipe diameter and face *** results showed that the wave reduction efficiency decreased with increasing pipe diameter and face *** contrast,the sediment transport efficiency was enhanced by increasing pipe diameter but was not affected significantly by varying face slopes.

关键词： Breakwaters Computational fluid dynamics Sediment transport Shoreline protection Coastal engineering ANSYS FLUENT

Diabetic peripheral neuropathy and neuromodulation techniques:a systematic review of progress and prospects

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Neural Regeneration Research 2025年第8期20卷 2218-2230页

作者： Rahul Mittal Keelin McKenna grant Keith Evan McKenna Joana R.N.Lemos Jeenu Mittal Khemraj Hirani Diabetes Research Institute University of Miami Miller School of MedicineMiamiFLUSA Department of Otolaryngology University of Miami Miller School of MedicineMiamiFLUSA Herbert Wertheim College of Medicine Florida International UniversityMiamiFLUSA School of Medicine and Public Health University of WisconsinMadisonWIUSA

Neuromodulation for diabetic peripheral neuropathy represents a significant area of interest in the management of chronic pain associated with this *** peripheral neuropathy,a common complication of diabetes,is characterized by nerve damage due to high blood sugar levels that lead to symptoms,such as pain,tingling,and numbness,primarily in the hands and *** aim of this systematic review was to evaluate the efficacy of neuromodulatory techniques as potential therapeutic interventions for patients with diabetic peripheral neuropathy,while also examining recent developments in this *** investigation encompassed an array of neuromodulation methods,including frequency rhythmic electrical modulated systems,dorsal root ganglion stimulation,and spinal cord *** systematic review suggests that neuromodulatory techniques may be useful in the treatment of diabetic peripheral *** the advantages of these treatments will enable physicians and other healthcare providers to offer additional options for patients with symptoms refractory to standard pharmacologic *** these efforts,we may improve quality of life and increase functional capacity in patients suffering from complications related to diabetic neuropathy.

关键词： diabetes mellitus diabetic peripheral neuropathy neuromodulation neurostimulation therapy non-pharmacological treatment pain management

Spatially-Structured Sharing Technique for Multimodal Problems

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Journal of Computer Science & Technology 2008年第1期23卷 64-76页

作者： grant Dick Peter Whigham Department of Information Science University of OtagoDunedin

Spatially-structured populations are one approach to increasing genetic diversity in an evolutionary algorithm （EA）. However, they are susceptible to convergence to a single peak in a multimodal fitness landscape. Niching methods, such as fitness sharing, allow an EA to maintain multiple solutions in a single population, however they have rarely been used in conjunction with spatially-structured populations. This paper introduces local sharing, a method that applies sharing to the overlapping demes of a spatially-structured population. The combination of these two methods succeeds in maintaining multiple solutions in problems that have previously proved difficult for sharing alone （and vice-versa）.

关键词： evolutionary algorithm multimodal problem domain sharing spatially-structured population

Precambrian supercontinents,glaciations,atmospheric oxygenation,metazoan evolution and an impact that may have changed the second half of Earth history

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Geoscience Frontiers 2013年第3期4卷 247-261页

作者： grant M.Young Department of Earth Sciences Western University1151 Richmond Street NLondonOntarioCanada N6A 5B7

In more than 4 Ga of geological evolution, the Earth has twice gone through extreme climatic perturba- tions, when extensive glaciations occurred, together with alternating warm periods which were accom- panied by atmospheric oxygenation. The younger of these two episodes of climatic oscillation preceded the Cambrian ＂explosion＂ of metazoan life forms, but similar extreme climatic conditions existed between about 2.4 and 2.2 Ga. Over long time periods, changing solar luminosity and mantle temperatures have played important roles in regulating Earth＇s climate but both periods of climatic upheaval are associated with supercontinents. Enhanced weathering on the orogenically and thermally buoyed supercontinents would have stripped CO2 from the atmosphere, initiating a cooling trend that resulted in continental glaciation. Ice cover prevented weathering so that CO2 built up once more, causing collapse of the ice sheets and ushering in a warm climatic episode. This negative feedback loop provides a plausible explanation for multiple glaciations of the Early and Late Proterozoic, and their intimate association with sedimentary rocks formed in warm climates. Between each glacial cycle nutrients were flushed into world oceans, stimulating photosynthetic activity and causing oxygenation of the atmosphere. Accommodation for many ancient glacial deposits was provided by rifting but escape from the climatic cycle was predicated on break- up of the supercontinent, when flooded continental margins had a moderating influence on weathering. The geochemistry of Neoproterozoic cap carbonates carries a strong hydrothermal signal, suggesting that they precipitated from deep sea waters, overturned and spilled onto continental shelves at the termination of glaciations. Paleoproterozoic （Huronian） carbonates of the Espanola Formation were probably formed as a result of ponding and evaporation in a hydrothermally influenced, restricted rift setting. Why did metazoan evolution not take off a

关键词： Proterozoic supercontinents Glaciations Impacts Oxygenation Metazoa

Studying the genetic basis of speciation in high gene flow marine invertebrates

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Current Zoology 2016年第6期62卷 643-653页

作者： grant H. POGSON Department of Ecology and Evolutionary Biology University of California Santa Cruz CA 95064 USA

A growing number of genes responsible for reproductive incompatibilities between species （barrier loci） exhibit the signals of positive selection. However, the possibility that genes experiencing positive selection diverge early in speciation and commonly cause reproductive incompatibilities has not been systematically investigated on a genome-wide scale. Here, I outline a research program for studying the genetic basis of speciation in broadcast spawning marine invertebrates that uses a priori genome-wide information on a large, unbiased sample of genes tested for positive selection. A targeted sequence capture approach is proposed that scores single-nucleotide polymorphisms （SNPs） in widely separated species populations at an early stage of allopatric divergence. The targeted capture of both coding and non-coding sequences enables SNPs to be characterized at known locations across the genome and at genes with known selective or neutral histories. The neutral coding and non-coding SNPs provide robust background distributions for identifying Fsm-outliers within genes that can, in principle, identify specific mutations experiencing diversifying selection. If natural hybridization occurs between species, the neutral coding and noncoding SNPs can provide a neutral admixture model for genomic clines analyses aimed at finding genes exhibiting strong blocks to introgression. Strongylocentrotid sea urchins are used as a model system to outline the approach but it can be used for any group that has a complete reference genome available.

关键词： barrier loci Bobzhansky-Muller incompatibilities FsToutliers genome scan introgression positive selection sequence capture speciation.

Did prolonged two-stage fragmentation of the supercontinent Kenorland lead to arrested orogenesis on the southern margin of the Superior province?

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Geoscience Frontiers 2015年第3期6卷 419-435页

作者： grant M.Young Department of Earth Sciences University of Western Ontario

Recent geochronological investigations reinforce the early suggestion that the upper part of the Paleoproterozoic Huronian Supergroup of Ontario, Canada is present in the Animikie Basin on the south shore of Lake Superior. These rocks, beginning with the glaciogenic Gowganda Formation, are interpreted as passive margin deposits. The absence of the lower Huronian （rift succession） from the Animikie Basin may be explained by attributing the oldest Paleoroterozoic rocks in the Animikie Basin （Chocolay Group） to deposition on the upper plate of a north-dipping detachment fault, which lacks sediments of the rift phase. Following thermal uplift that led to opening of the Huronian Ocean on the south side of what is now the Superior province, renewed uplift （plume activity） caused large-scale gravitational folding of the Huronian Supergroup accompanied by intrusion of the Nipissing diabase suite and Senneterre dikes at about 2.2 Ga. Termination of passive margin sedimentation is normally followed by ocean closure but in the Huronian and Animikie basins there was a long hiatus - the Great Stratigraphic Gap - which lasted for about 350 Ma. This hiatus is attributed to a second prolonged thermal uplift of part of Kenorland that culminated in complete dismemberment of the supercontinent shortly before 2.0 Ga by opening of the Circum-Superior Ocean. These events caused regional uplift （the Great Stratigraphic Gap） and delayed completion of the Huronian Wilson Cycle until a regional compressional tectonic episode, including the Penokean orogeny, belatedly flooded the southern margin of the Superior province with foreland basin deposits, established the limits of the Superior structural province and played an important role in constructing Laurentia.

关键词： Paleoproterozoic Glaciation Plate tectonics Mantle plumes Supercontinents

Windows of opportunity:a new tree-shrub dynamic at alpine treeline?

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National Science Review 2023年第10期10卷 13-14页

作者： grant P.Elliott Department of Geography University of Missouri

Of increasing importance while the climate is under the influence of chronic environmental change driven by rising levels of CO2,temperature and vapor pressure deficit(VPD),is understanding how vegetation will respond over space and time as we cross critical thresholds [1].This is especially true in mountain regions where amplified rates of warming are expected to affect the elevational zonation of plant communities [2].

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Environmental upheavals of the Ediacaran period and the Cambrian “explosion” of animal life

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Geoscience Frontiers 2015年第4期6卷 523-535页

作者： grant M.Young Department of Earth Sciences University of Western Ontario

The second half of the Ediacaran period began with a large impact - the Acraman impact in South Australia, which was accompanied by a negative δ^13Ccarb anomaly and an extinction-radiation event involving acritarchs. A few million years later （-570 Ma？） there was a second, deeper and longer-lived world-wide δ^13Ccarb anomaly （the Shuram anomaly） which coincides with extinction of the acanthomorphic acritarchs. Wide distribution of the Shuram event is exemplified by stratigraphic sections from South Australia, Oman, southern California and South China. The widespread anomaly has been tentatively attributed to a marine impact. During recovery from the Shuram event the enigmatic Ediacaran biota achieved its zenith, only to be extirpated and replaced by a polyphyletic assemblage of shelly animals in what is known as the Cambrian ＂explosion＂. This extinction-radiation cycle was preceded by glaciation, another δ^13Ccarb excursion and the highest ^87Sr/^86Sr values known from marine carbonates. These high Sr ratios have been linked to weathering of extensive tracts of continental crust that were elevated during amalgamation of the supercontinent Gondwana. Introduction of essential nutrients to the oceans would have promoted biological production of oxygen and provided P and Ca for the important skeletonization that characterizes the Cambrian ＂explosion＂ and caused a quantum leap in the preservation potential of animal remains. Turbulent events of the last 50 million years of Precambrian time include three glaciations, two large impacts and a massive orogenic episode. These dramatic environmental upheavals are held responsible for three consecutive extinction-radiation cycles that culminated in the appearance of a diverse array of shelly fossils. Various lines of evidence suggest that the metazoans have deep roots so that they too may have been subjected to the environmental pressures of the late Ediacaran period clearly illustrated by acritarchs and the Ediacaran biota but

关键词： Ediacaran Sburam Impacts Orogeny Cambrian explosion

MULTIFAMILY AFFORDABLE HOUSING THAT IS HEALTHY,EFFICIENT,COST EFFECTIVE AND LEED PLATINUM

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Journal of Green Building 2017年第1期12卷 36-44页

作者： Sharon Patterson grant Eco Edge.PO Box 6205 KetchumID 83340

INTRODUCTION A developer who had chronic asthma as a child built the first LEED^(■)(Leadership in Energy and Environmental Design)Platinum certified apartment complex in *** has also heard from two residents that their asthma no longer resulted in attacks due to eliminating triggers in the interior *** years and a dozen multifamily affordable housing projects later,the LEED consultant on these projects has gathered insight on best practices,lessons learned and strate-gies that result in resident,owner and project team *** projects have achieved LEED Platinum certification(two more are still under construction,but are on track for Platinum),and the HERS(Home Energy Rating System)scores are as low as *** has been collected on what works,what doesn’t and what matters most:from low energy bills to living in a healthy home and not having asthma *** projects debunk the assumptions that energy effi-ciency adds too much cost or that green homes are only for the wealthy.

关键词： LEED healthy homes energy efficient cost effective asthma affordable housing green building integrated design design charrette high performance

Bioinspired nanocomposites with self-adaptive mechanical properties

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Nano Research 2024年第2期17卷 633-648页

作者： grant Kitchen Bohan Sun Sung Hoon Kang 13400 N Charles St Department of Materials Science and EngineeringJohns Hopkins UniversityBaltimore 21218USA 23400 N Charles St Department of Mechanical EngineeringJohns Hopkins UniversityBaltimore 21218USA 33400 N Charles St Hopkins Extreme Materials InstituteJohns Hopkins UniversityBaltimore 21218USA

Conventional synthetic materials have fixed mechanical properties and suffer defects,damage,and degradation over *** makes them unable to adapt to changing environments and leads to limited ***,self-adaptive materials inspired by natural materials have emerged as a solution to address these *** the ability to change their mechanical properties based on changing mechanical environments,repairing defects,and maintaining their mechanical properties,these materials can lead to improved performance while decreasing *** this review,we explore self-adaptive phenomena found in nature that have inspired the development of synthetic self-adaptive materials,and the mechanisms that have been employed to create the next generation of *** potential applications of these materials,the challenges that existing approaches face,and future research opportunities are also discussed.

关键词： nanocomposites self-adaptive materials bioinspired materials force-activated resilience