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Constraints on treeline advance in a warming climate:a test of the reproduction limitation hypothesis

Journal of Plant Ecology 2018年第3期11卷 411-422页

作者： Dasvinder kambo ryan k.danby Department of Geography Queen’s University99 University AvenueKingstonOntario K7L 3N6Canada School of Environmental Studies Queen’s University99 University AvenueKingstonOntario K7L 3N6Canada

Aims Several mechanistic hypotheses have been developed to explain the existence of alpine treelines *** reproduction limita-tion hypothesis(RLH)postulates that reproductive processes such as seed production and dispersal are restricted in treeline envi-ronments,thereby limiting the establishment of new individuals in advance of extant *** its popularity,no study has tested this hypothesis in a comprehensive *** this experi-ment,we attempted to answer whether there are enough viable seeds being dispersed beyond treeline for sexually mediated tree-line advance,and what the implications of climate change might be on these *** We established 30 plots across two aspects(north ***)and three elevational habitats(forest,treeline and tundra)in a white spruce(Picea glauca)boreal forest-alpine tundra ecotone in south-west Yukon,*** each plot,tree characteristics,seed produc-tion and predispersal damage were ***,eight dispersal trays were positioned in each plot to measure seed rain,and germination trials with and without predation exclosures were constructed in a subset of plots to quantify dispersal and germina-tion *** Findings Results were highly variable both temporally and *** 2014,a mast year,69%of adult trees produced cones compared to 0.4%in the following *** density of trees in forest plots compared to treeline and tundra resulted in greater seed production at lower *** all plots,88%of seeds were damaged before dispersal or were not *** plots had significantly greater predispersal *** rain was greater in south-facing plots than north-facing *** than 2%of seeds produced on the landscape were dispersed into Tundra plots,located 50 m above *** was a net movement of seeds from the north-facing slope to the south at our study site,likely due to prevailing winds during the dispersal *** counts were more

关键词： altitudinal gradients treeline dynamics predispersal seed damage seed predation seed masts ecotones

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Capitalizing on Superconvergence for More Accurate Multi‑Resolution Discontinuous Galerkin Methods

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Communications on Applied Mathematics and Computation 2022年第2期4卷 417-436页

作者： Jennifer k.ryan Applied Mathematics and Statistics Colorado School of MinesGoldenCO 80401USA

This article focuses on exploiting superconvergence to obtain more accurate multi-resolution analysis. Specifcally, we concentrate on enhancing the quality of passing of information between scales by implementing the Smoothness-Increasing Accuracy-Conserving (SIAC) fltering combined with multi-wavelets. This allows for a more accurate approximation when passing information between meshes of diferent resolutions. Although this article presents the details of the SIAC flter using the standard discontinuous Galerkin method, these techniques are easily extendable to other types of data.

关键词： Multi-resolution analysis Multi-wavelets Discontinuous Galerkin Smoothness-Increasing Accuracy-Conserving(SIAC) Post-processing Superconvergence Accuracy enhancement

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A comparison of centrifugation and tangential flow filtration for nanoparticle purification: A case study on acetalated dextran nanoparticles

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Particuology 2020年第3期18卷 189-196页

作者： Nishan k.Shah ryan Ivone Jie Shen Samantha A.Meenach University of Rhode Island College of PharmacyDepartment of Biomedical and Pharmaceutical SciencesKingstonRI 02881USA University of Rhode Island College of EngineeringDepartment of Chemical EngineeringKingstonRI 02881USA

Tangential fiow filtration (TFF) is a purification method commonly used in a multitude of fields,including particle ***,there is still a lack of comprehensive understanding of the effects of key TFF parameters on nanoparticle (NP) characteristics (purification outcomes).The present study aimed to investigate the influence of various factors on the characteristics of TFF-purified *** most commonly used NP purification method,centrifugation,was studied as a control.A design of experiment approach was implemented to investigate the influence of transmembrane pressure,flow rate,and initial drug loading on NP characteristics using paclitaxel as a model small *** the determination of optimized TFF parameters,the two purification methods were assessed using other model small molecules (*** and resveratrol).The results indicated that the TFF parameters and initial loading of the drug played important roles in the purified NP *** with the centrifugation method,TFF resulted in smaller NP with higher drug *** was able to circumvent issues associated with conventional centrifugation,while yielding similar results,and can potentially serve as a suitable large-scale purification method for polymeric NP.

关键词： Tangential flow filtration Nanoparticle purification Box-Behnken design Acetalated dextran Drug delivery

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Superconvergence and the Numerical Flux: a Study Using the Upwind-Biased Flux in Discontinuous Galerkin Methods

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Communications on Applied Mathematics and Computation 2020年第3期2卷 461-486页

作者： Daniel J.Frean Jennifer k.ryan School of Mathematics University of East AngliaNorwichUK Applied Mathematics and Statistics Colorado School of MinesGoldenCOUSA

One of the beneficial properties of the discontinuous Galerkin method is the accurate wave propagation *** is,the semi-discrete error has dissipation errors of order 2k+1(≤Ch2k+1)and order 2k+2 for dispersion(≤Ch2k+2).Previous studies have concentrated on the order of accuracy,and neglected the important role that the error constant,C,plays in these *** this article,we show the important role of the error constant in the dispersion and dissipation error for discontinuous Galerkin approximation of polynomial degree k,where k=0,1,2,*** gives insight into why one may want a more centred flux for a piecewise constant or quadratic approximation than for a piecewise linear or cubic *** provide an explicit formula for these error *** is illustrated through one particular flux,the upwind-biased flux introduced by Meng et al.,as it is a convex combination of the upwind and downwind *** studies of wave propagation are typically done through a Fourier *** higher order Fourier information can be extracted using the smoothness-increasing accuracy-conserving(SIAC)*** SIAC filter ties the higher order Fourier information to the negative-order norm in physical *** show that both the proofs of the ability of the SIAC filter to extract extra accuracy and numerical results are unaffected by the choice of flux.

关键词： Discontinuous Galerkin Smoothness-increasing accuracy-conserving(SIAC)filtering Superconvergence

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Strategies in boosting photosensitization for biomedical applications

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Science China Chemistry 2022年第4期65卷 647-649页

作者： Ming Chen ryan T.k.kwok Youhong Tang Dan Ding College of Chemistry and Materials Science Jinan UniversityGuangzhou 510632China Frontiers Science Center for Cell Responses State Key Laboratory of Medicinal Chemical BiologyKey Laboratory of Bioactive MaterialsMinistry of EducationCollege of Life SciencesNankai UniversityTianjin 300071China Department of Nephrology Huai’an Hospital Affiliated to Xuzhou Medical College and Huai’an Second HospitalHuai’an 223002China Department of Chemistry The Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and ReconstructionInstitute for Advanced StudyDepartment of Chemical and Biological EngineeringThe Hong Kong University of Science and TechnologyHong KongChina Australia-China Joint Centre for Personal Health Technologies Medical Device Research InstituteCollege of Science and EngineeringFlinders UniversitySouth Australia 5042Australia Guangdong Provincial key Laboratory of Luminescence from Molecular Aggregates South China University of TechnologyGuangzhou 510640China

Photodynamic therapy(PDT)has emerged as an effective treatment method for its few adverse effects,little invasiveness,short treatment time and low cost[1,2].The rapid development of PDT has dramatically boosted its mu... 详细信息

关键词： treatment boosting immunotherapy

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Efficient HIV-1 in vitro reverse transcription: optimal capsid stability is required

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Signal Transduction and Targeted Therapy 2021年第2期6卷 195-196页

作者： ryan C.Burdick Vinay k.Pathak Viral Mutation Section HIV Dynamics and Replication ProgramCenter for Cancer ResearchNational Cancer Institute at FrederickFrederickMD 21702USA

Recently,Christensen et *** HIV-1 reverse transcription and integration in a cell-free system and found that viral double-stranded DNA that is capable of integration into a target plasmid DNA was efficiently synthesized within viral cores,indicating that the capsid protein shell plays an important role in viral genome replication.1 HIV-1 reverse transcriptase(RT)copies the viral genomic RNA into a double-stranded DNA,and HIV-1 integrase(IN)inserts the viral DNA into the host genome to form a *** RT and IN have been successfully targeted with potent antiretroviral drugs to inhibit these enzymes and treat patients infected with HIV-1,the causative agent of acquired immunodeficiency syndrome(AIDS).Despite decades of research,the molecular mechanisms of reverse transcription and integration in vivo are not fully characterized,in part because cell-free assays that efficiently and faithfully recapitulate the processes in the context of a virion have not been available。

关键词： al. drugs optimal

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Nexus between polymer support and metal oxide nanoparticles in hybrid nanosorbent materials （HNMs） for sorption/desorption of target ligands

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Frontiers of Environmental Science & Engineering 2015年第5期9卷 929-938页

作者： ryan C. SMITH Jinze LI Surapol PADUNGTHON Arup k. SENGUPTA Environmental Engineering Program Department of Civil and Environmental Engineering Lehigh University Bethlehem PA 18015 USA

Metal oxide nanoparticles like hydrated ferric oxide （HFO） or hydrated zirconium oxide （HZrO） are excellent sorbents for environmentally significant ligands like phosphate, arsenic, or fluoride, present at trace concentrations. Since the sorption capacity is surface dependent for HFO and HZrO, nanoscale sizes offer significant enhancement in performance. However, due to their miniscule sizes, low attrition resistance, and poor durability they are unable to be used in typical plug-flow column setups. Meanwhile ion exchange resins, which have no specific affinity toward anionic ligands, are durable and chemically stable. By impregnating metal oxide nanoparticles inside a polymer support, with or without functional groups, a hybrid nanosorbent material （HNM） can be prepared. A HNM is durable, mechanically strong, and chemically stable. The functional groups of the polymeric support will affect the overall removal effi- ciency of the ligands exerted by the Donnan Membrane Effect. For example, the removal of arsenic by HFO or the removal of fluoride by HZrO is enhanced by using anion exchange resins. The HNM can be precisely tuned to remove one type of contaminant over another type. Also, the physical morphology of the support material, spherical bead versus ion exchange fiber, has a significant effect on kinetics of sorption and desorption. HNMs also possess dual sorption sites and are capable of removing multiple contaminants, namely, arsenate and perchlorate, concurrently.

关键词： ion exchange sorpfion arsenic perchlorat~,fluoride

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Unmet supportive care needs in families of children with chronic health conditions: an Australian cross‑sectional study

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World Journal of Pediatrics 2023年第12期19卷 1181-1191页

作者： Sangeetha Thomas Linda k.Byrne Nicholas P.ryan Christel Hendrieckx Victoria White School of Psychology Faculty of HealthDeakin UniversityMelbourneVIC 3125Australia Department of Paediatrics University of MelbourneMelbourneVICAustralia Australian Centre for Behavioural Research in Diabetes MelbourneVICAustralia Institute of Health Transformation Deakin UniversityMelbourneVICAustralia Cancer Council Victoria MelbourneVICAustralia

Background The aim of this study was to identify similarities and diferences in the unmet supportive care needs(USCN)of families of children with major chronic health conditions(CHCs)using a universal need assessment *** A cross-sectional online survey involving parents of children with congenital heart disease(CHD),type 1 diabetes mellitus(T1D),cancer,and asthma diagnosed within the last 5 years recruited via social media and support ***-four items assessing the USCN across six domains(care needs,physical and social needs,informational needs,support needs,fnancial needs,child-related emotional needs)were responded to on a 4-point Likert scale[no need(1)to high need(4)].Descriptive statistics identifed the level of need,and linear regressions identifed factors associated with higher need domain *** to small numbers,the asthma group was excluded from comparisons across *** One hundred and ninety-four parents completed the survey(CHD:n=97,T1D:n=50,cancer:n=39,and asthma:n=8).Parents of children with cancer were most likely to report at least one USCN(92%),followed by parents of children with T1D(62%).The fve most commonly reported USCN across CHCs were drawn from four domains:child-related emotional,support,care,and *** need items were included in the top fve needs for all conditions.A higher USCN was associated with a greater frequency of hospital visits and the absence of parental *** Using a universal need assessment tool,this is one of the frst studies to characterize USCN in families of children diagnosed with common *** proportions endorsing diferent needs varied across conditions,the most endorsed needs were similar across the illness *** suggests that support programs or services could be shared across diferent CHCs.

关键词： Children Chronic illness Need assessment Unmet supportive care needs

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Compositionally restricted attention-based network for materials property predictions

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npj Computational Materials 2021年第1期7卷 684-693页

作者： Anthony Yu-Tung Wang Steven k.kauwe ryan J.Murdock Taylor D.Sparks Fachgebiet keramische Werkstoffe/Chair of Advanced Ceramic Materials Technische Universität BerlinBerlinGermany Department of Materials Science&Engineering University of UtahSalt Lake CityUTUSA

In this paper,we demonstrate an application of the Transformer self-attention mechanism in the context of materials *** network,the Compositionally Restricted Attention-Based network(CrabNet),explores the area of structure-agnostic materials property predictions when only a chemical formula is *** results show that CrabNet’s performance matches or exceeds current best-practice methods on nearly all of 28 total benchmark *** also demonstrate how CrabNet’s architecture lends itself towards model interpretability by showing different visualization approaches that are made possible by its *** feel confident that CrabNet and its attention-based framework will be of keen interest to future materials informatics researchers.

关键词： network property restricted

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The Impact of a Prior Norwood Procedure on Cardiac Transplantation in Failed Fontan Physiology

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Congenital Heart Disease 2024年第3期19卷 257-266页

作者： ryan G.McQueen Nikki M.Singh Ronald k.Woods Medical College of Wisconsin Herma Heart Institute at Children’s WisconsinMilwaukeeUSA Division of Pediatric Cardiology Medical College of WisconsinHerma Heart Institute at Children’s WisconsinMilwaukeeUSA Division of Pediatric Cardiothoracic Surgery Medical College of WisconsinHerma Heart Institute at Children’s WisconsinMilwaukeeUSA

Objective:The objective of this study was to compare cardiac transplant operative and postoperative courses of patients with failed Fontan physiology who were initially palliated with a Norwood(FFN)to those without a prior Norwood(FF).Methods:A single-institution retrospective review of all patients with Fontan failure who under-went cardiac transplantation from 2003–2021 was completed-22 underwent prior Norwood(FFN)and 11 did not(FF).Descriptive and inferential statistics were calculated for operative course and patient ***:The operative course of the FFN cohort appeared to be more complex(not statistically significant,but clinically relevant)-this group exclusively experienced sternal re-entry events(3 of 22 patients)and concomitant neo-aor-tic reconstruction(6 patients),had a longer duration of surgery(median of 682 min vs.575.5 min),more time on circulatory arrest(median of 25.5 min vs.12.5 min),and more frequent use of open sternal management[50%of patients(11/22)vs.27.3%of patients(3/11)].Postoperatively,these patients underwent more mediastinal explora-tions[other than sternal closure;40.9%of patients(9/22)vs.18.2%of patients(2/11)],spent more time on mechanical ventilation(median of 5 days vs.2 days),had a longer length of stay(median of 30 days vs.19 days),and required more catheter-based re-interventions[22.7%of patients(5/22)vs.9.1%of patients(1/11)].Conclu-sion:Although underpowered,our results suggest that the operative course of FFN patients is more challenging,based mostly on neo-aortic arch *** turn,this likely leads to a more complex postoperative *** are currently collaborating with other institutions to increase the cohort size and power of the study.

关键词： Fontan Fontan failure Norwood cardiac transplantation

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