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Thz-Enhanced DC Ultrafast Electron Diffractometer

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Ultrafast Science 2021年第1期1卷 61-67页

作者： Dongfang Zhang Tobias Kroh Felix Ritzkowsky Timm Rohwer Moein Fakhari huseyin Cankaya Anne-Laure Calendron nicholas h.matlis Franz X.Kärtner Center for Free-Electron Laser Science Deutsches Elektronen SynchrotronNotkestrasse 8522607 HamburgGermany Collaborative Innovation Center for IFSA School of Physics and AstronomyShanghai Jiao Tong University200240 ShanghaiChina Department of Physics and The hamburg Centre for Ultrafast Imaging Universität HamburgLuruper Chaussee 14922761 HamburgGermany

Terahertz-(Thz-)based electron manipulation has recently been shown to hold tremendous promise as a technology for manipulating and driving the next generation of compact ultrafast electron ***,we demonstrate an ultrafast electron diffractometer with Thz-driven pulse *** electron bunches from a conventional DC gun are compressed by a factor of 10 and reach a duration of~180 fs(FWhM)with 10,000 electrons/pulse at a 1 khz repetition *** resulting ultrafast electron source is used in a proof-of-principle experiment to probe the photoinduced dynamics of single-crystal *** Thz-compressed electron beams produce high-quality diffraction patterns and enable the observation of the ultrafast structural dynamics with improved time *** results validate the maturity of Thz-driven ultrafast electron sources for use in precision applications.

关键词： pulse Electron repetition

Is speciation driven by cycles of mixing and isolation?

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National Science Review 2019年第2期6卷 291-292页

作者： nicholas h.Barton Institute of Science and Technology Austria NSR

he et al.[1] describe genetic divergence between mangrove species that are distributed across the Straits of Malacca. Divergence varies much more across the genome than in a simple null model of strict allopatry. Such heterogeneity (often termed ‘genomic islands of speciation’) can be generated by population structure:populations that exchange genes at a low rate will

关键词： Rev

Plant responses to arbuscular mycorrhizae under elevated temperature and drought

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Journal of Plant Ecology 2017年第4期10卷 692-701页

作者： Phyllis h.Pischl nicholas A.Barber Department of Biological Sciences Northern Illinois UniversityDeKalbIL 60115USA Institute for the Study of the Environment Sustainabilityand EnergyNorthern Illinois UniversityDeKalbIL 60115USA

Aims Climate change is predicted to cause both increased temperatures and changes in precipitation,leading to more severe droughts in some *** these changes will affect plant growth may depend in part on biotic *** vascular plants form symbiotic rela-tionships with arbuscular mycorrhizal fungi(AMF),root symbionts that provide soil nutrients to plants in exchange for carbohydrates,which may reduce the effects of environmental stresses on *** investigated if AMF modified temperature and drought effects on plant growth,fitness and defenses against *** We manipulated AMF presence,temperature and water availability on bell pepper plants(Capsicum annuum L.)in a field setting to measure plant growth and fitness *** a growth chamber experiment,we also investigated if AMF influenced insect herbi-vores feeding on plants at elevated *** findings Drought consistently reduced plant growth,and AMF did not change drought ***,with sufficient water,AMF tended to benefit plant growth and flower production(but not fruit production)compared to non-mycorrhizal *** the growth chamber,temperature and AMF influenced plant protein and phos-phorus contents,but not defensive chemistry or herbivore ***,AMF may ameliorate the effects of temperature stress due to climate change on plants by increasing growth and nutrient content,but these effects do not extend to the constitutive herbivory defenses examined here.

关键词： aboveground-belowground arbuscular mycorrhizal fungi climate change drought herbivore indirect effects

Pathway analysis for genome-wide genetic variation data:Analytic principles,latest developments,and new opportunities

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Journal of Genetics and Genomics 2021年第3期48卷 173-183页

作者： Micah Silberstein nicholas Nesbit Jacquelyn Cai Phil h.Lee Center for Genomic Medicine Massachusetts General HospitalBostonMA 02114USA Department of Psychiatry Harvard Medical SchoolBostonMA 02115USA Stanley Center for Psychiatric Research Broad Institute of MIT and HarvardCambridgeMA 02142USA

Pathway analysis,also known as gene-set enrichment analysis,is a multilocus analytic strategy that integrates a priori,biological knowledge into the statistical analysis of high-throughput genetics *** developed for the studies of gene expression data,it has become a powerful analytic procedure for indepth mining of genome-wide genetic variation *** discoveries were made in the past years,uncovering genes and biological mechanisms underlying common and complex ***,as massive amounts of diverse functional genomics data accrue,there is a pressing need for newer generations of pathway analysis methods that can utilize multiple layers of high-throughput genomics *** this review,we provide an intellectual foundation of this powerful analytic strategy,as well as an update of the state-of-the-art in recent method *** goal of this review is threefold:(1)introduce the motivation and basic steps of pathway analysis for genome-wide genetic variation data;(2)review the merits and the shortcomings of classic and newly emerging integrative pathway analysis tools;and(3)discuss remaining challenges and future directions for further method developments.

关键词： Pathway analysis Set-based association analysis Gene-set enrichment analysis Genome-wide association study Multilocus association analysis

Modelling of Propagating Shear Waves in Biotissue Employing an Internal Variable Approach to Dissipation

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Communications in Computational Physics 2008年第3期3卷 603-640页

作者： h.T.Banks nicholas S.Luke Center for Research in Scientific Computation North Carolina State UniversityRaleighNC 27695-8205USA.

The ability to reliably detect coronary artery disease based on the acousticnoises produced by a stenosis can provide a simple, non-invasive technique for *** research exploits the shear wave fields in body tissue to detect andanalyze coronary stenoses. The methods and ideas outlined in earlier efforts [6] includinga mathematical model utilizing an internal strain variable approximation tothe quasi-linear viscoelastic constitutive equation proposed by Fung in [19] is extendedhere. As an initial investigation, a homogeneous two-dimensional viscoelastic geometryis considered. Being uniform in θ, this geometry behaves as a one dimensionalmodel, and the results generated from it are compared to the one dimensional resultsfrom [6]. To allow for different assumptions on the elastic response, several variationsof the model are considered. A statistical significance test is employed to determine ifthe more complex models are significant improvements. After calibrating the modelwith a comparison to previous findings, more complicated geometries are *** involving a heterogeneous geometrywith a uniformring running throughthe original medium, a θ-dependent model which considers a rigid partial occlusionformed along the inner radius of the geometry, and a model which combines the ringand occlusion are presented.

关键词： Viscoelasticity partial differential equations shear waves biotissue.

Combined risk modelling approach to identify the optimal carotid revascularisation approach

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Stroke & Vascular Neurology 2021年第3期6卷 476-482,I0080-I0084页

作者： James Francis Burke Lewis B Morgenstern nicholas h Osborne Rodney A hayward Neurology University of Michigan Michigan MedicineAnn ArborMichiganUSA Vascular Surgery Univerity of Michigan MedicineAnn ArborMichiganUSA Internal Medicine University of Michigan Michigan MedicineAnn ArborMichiganUSA

Background Carotid endarterectomy(CEA)results in fewer perioperative strokes,but more myocardial infarctions(MI)than carotid artery stenting(CAS).We explored a combined modelling approach that stratifies patients by baseline stroke and *** Baseline registry-based risk models for perioperative stroke and MI were identified via literature *** then selected treatment risk models in the Carotid Revascularisation Stenting versus Endarterectomy(CREST)trial by serially adding covariates(baseline risk,treatment(CEA vs CAS),treatment-risk interaction and age-treatment interaction terms).Treatment risk models were externally validated using data from the Society for Vascular Surgery(SVS)Vascular Quality Initiative(VQI)CEA and carotid stenting registries and treatment models were recalibrated to the SVS-VQI *** net benefit was estimated by summing the predicted stroke and MI risk differences with CEA versus *** Perioperative treatment models had moderate predictiveness(c-statistic 0.69 for stroke and 0.68 for MI)and reasonable calibration across the risk spectrum for both stroke and MI within *** external validation in SVS-VQI,predictiveness was substantially reduced(c-statistic 0.61 for stroke and 0.54 for MI)and models substantially overpredicted *** patients(86.7%)were predicted to have net benefit from CEA in CREST(97.0%of symptomatic patients vs 75%of asymptomatic patients).Discussion A combined modelling approach that separates risk elements has potential to inform optimal ***,our current approach is not ready for clinical *** data support guidelines that suggest that CEA should be the preferred revascularisation modality in most patients with symptomatic carotid stenosis.

关键词： carotid Surgery optimal

Clinical efficacy of the over-the-scope clip device: A systematic review

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World Journal of Gastroenterology 2020年第24期26卷 3495-3516页

作者： nicholas Bartell Krystle Bittner Vivek Kaul Truptesh h Kothari Shivangi Kothari Division of Gastroenterology and hepatology University of Rochester Medical CenterRochesterNY 14642United States

BACKGROUND The over-the-scope clip(OTSC)system has been increasingly utilized as a nonsurgical option to endoscopically manage refractory gastrointestinal(GI)hemorrhage,perforations/luminal defects and *** data exist evaluating the efficacy and safety of *** To determine the clinical success and adverse event(AE)rates of OTSC across all GI *** A PubMed search was conducted for eligible articles describing the application of the OTSC system for any indication in the GI *** article or case series reporting data for less than 5 total patients was *** primary outcome was the rate of clinical *** outcomes included:Technical success rate,OTSC-related AE rate and requirement for surgical intervention despite-OTSC *** rates(per-indication and overall)were calculated as the number of patients with the event of interest divided by the total number of *** A total of 85 articles met our inclusion criteria(n=3025 patients).OTSC was successfully deployed in 94.4%of patients(n=2856/3025).The overall rate of clinical success(all indications)was 78.4%(n=2371/3025).Per-indication clinical success rates were as follows:(1)86.0%(1120/1303)for GI hemorrhage;(2)85.3%(399/468)for perforation;(3)55.8%(347/622)for fistulae;(4)72.6%(284/391)for anastomotic leaks;(5)92.8%(205/221)for defect closure following endoscopic resection(e.g.,following endoscopic mucosal resection or endoscopic submucosal dissection);and(6)80.0%(16/20)for stent ***’s related to the deployment of OTSC were only reported in 64 of 85 studies(n=1942 patients),with an overall AE rate of 2.1%(n=40/1942).Salvage surgical intervention was required in 4.7%of patients(n=143/3025).CONCLUSION This systematic review demonstrates that the OTSC system is a safe and effective endoscopic therapy to manage GI hemorrhage,perforations,anastomotic leaks,defects created by endoscopic resections and for stent *** success in fistula

关键词： Over-the-scope clip hemostasis Perforation Fistula closure Endoscopic resection Anastomotic leak Ovesco Endoscopy

Feeding the world: impacts of elevated [CO_(2)] on nutrient content of greenhouse grown fruit crops and options for future yield gains

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horticulture Research 2023年第4期10卷 83-100页

作者： nicholas h.Doddrell Tracy Lawson Christine A.Raines Carol Wagstaff Andrew J.Simkin NIAB New RoadEast MallingKentME196BJ UK Department of Food and Nutritional Sciences University of ReadingWhiteknightsReadingBerkshire RG66DZUK School of Life Sciences University of EssexColchester CO44SQUK School of Biosciences University of KentCanterburyUnited Kingdom CT27NJUK

Several long-term studies have provided strong support demonstrating that growing crops under elevated[CO_(2)]can increase photosynthesis and result in an increase in yield,flavour and nutritional content(including but not limited to Vitamins C,E and pro-vitamin A).In the case of tomato,increases in yield by as much as 80%are observed when plants are cultivated at 1000 ppm[CO_(2)],which is consistent with current commercial greenhouse productionmethods in the tomato fruit *** results provide a clear demonstration of the potential for elevating[CO_(2)]for improving yield and quality in greenhouse *** major focus of this review is to bring together 50 years of observations evaluating the impact of elevated[CO_(2)]on fruit yield and fruit nutritional *** the final section,we consider the need to engineer improvements to photosynthesis and nitrogen assimilation to allow plants to take greater advantage of elevated CO_(2) growth conditions.

关键词： crops greenhouse content

Aggregation-induced emission polymers via reversible-deactivation radical polymerization Special Collection:Distinguished Australian Researchers

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Aggregate

Aggregate 2024年第1期5卷 16-46页

作者： nicholas Kai Shiang Teo Bo Fan Aditya Ardana San h.Thang School of Chemistry Monash UniversityClaytonVictoriaAustralia

Aggregation-induced emission(AIE)is a unique phenomenon whereby aggregation of molecules induces fluorescence emission as opposed to the more commonly known aggregation-caused quenching(ACQ).AIE has the potential to be utilized in the large-scale production of AIE-active polymeric materials because of their wide range of practical applications such as stimuli-responsive sensors,biological imaging agents,and drug delivery *** is evident from the increasing number of publications over the years since AIE was first *** addition,the evergrowing interest in this field has led many researchers around the world to develop new and creative methods in the design of monomers,initiators and crosslinkers,with the goal of broadening the scope and utility of AIE *** of the most promising approaches to the design and synthesis of AIE polymers is the use of the reversible-deactivation radical polymerization(RDRP)techniques,which enabled the production of well-controlled AIE materials that are often difficult to achieve by other *** this review,a summary of some recent works that utilize RDRP for AIE polymer design and synthesis is presented,including(i)the design of AIE-related monomers,initiators/crosslinkers;the achievements in preparation of AIE polymers using(ii)reversible addition–fragmentation chain transfer(RAFT)technique;(iii)atom transfer radical polymerization(ATRP)technique;(iv)other techniques such as Cu(0)-RDRP technique and nitroxide-mediated polymerization(NMP)technique;(v)the possible applications of these AIE polymers,and finally(vi)a summary/perspective and the future direction of AIE polymers.

关键词： aggregation-induced emission atom transfer radical polymerization nitroxide-mediated polymerization reversible addition–fragmentation chain transfer reversible-deactivation radical polymerization