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Bioactive Materials 2022年第8期7卷 302-312页

作者： Adam M.Navara Yu Seon Kim Yilan Xu christopher l.crafton Mani Diba Jason l.Guo Antonios G.Mikos Department of Bioengineering Rice University6500 Main StreetHoustonTX77030USA

Extrusion bioprinting is a popular method for fabricating tissue engineering scaffolds because of its potential to rapidly produce complex,bioactive or cell-laden ***,due to the relatively high viscosity required to maintain shape fidelity during printing,many extrusion-based inks lack the ability to achieve precise structures at scales lower than hundreds of *** this work,we present a novel poly(N-isopropylacrylamide)(PNIPAAm)-based ink and poloxamer support bath system that produces precise,multi-layered structures on the tens of micrometers *** support bath maintains the structure of the ink in a hydrated,heated environment ideal for cell culture,while the ink undergoes rapid thermogelation followed by a spontaneous covalent crosslinking *** the combination of the PNIPAAm-based ink and poloxamer bath,this system was able to produce hydrogel scaffolds with uniform fibers possessing diameters tunable from 80 to 200μm.A framework of relationships between several important printing factors involved in maintaining support and thermogelation was also *** a whole,this work demonstrates the ability to produce precise,acellular and cell-laden PNIPAAm-based scaffolds at high-resolution and contributes to the growing body of research surrounding the printability of extrusion-based bioinks with support baths.

关键词： Bioprinting Thermogelling macromer Tissue engineering Printability

Effect of cylinder wall parameters on the final packing density of mono-disperse spheres subject to three-dimensional vibrations Author links open overlay panel

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Particuology 2024年第8期91卷 211-225页

作者： Jack R.Grogan Andrei l.Nicuşan christopher R.K.Windows-Yule School of Chemical Engineering The University of BirminghamEdgbastonBirminghamB152TTUK

Achieving densely packed particles is desirable within the industries of ceramics,pharmaceuticals,defence and additive *** this work,we use the discrete element method(DEM)to determine the effect of wall parameters on the final packing density of mono-disperse spheres subject to 4 varying three-dimensional vibration and fill *** focus specifically on the impact of the container wall parameters on the particles'final packing *** on from the validation of the DEM simulation the particle-wall coefficient of restitution,the particle-wall coefficient of rolling friction and the particle-wall coefficient of sliding friction were varied individually and the effect on the final packing density *** relatively low particle-particle friction glass beads,the effect of these wall properties had no discernible effect on the final packing density *** on from these findings the particle-wall properties were varied at the extreme values of particle-particle coefficient of rolling friction and particle-particle coefficient of sliding *** a particle-particle coefficient of sliding friction=1,increases in particle-wall coefficient of restitution resulted in a minor increase in the final packing density of particles though this was not statistically *** a particle-particle coefficient of sliding friction=1,increases in particle-wall coefficient of rolling friction resulted in a minor decrease in the final packing density of the particles though again not to a degree where the trend can,with complete certainty,be distinguished from the random error across the ***,when the particle-particle coefficient of sliding friction=1,increases in particle-wall coefficient of sliding friction resulted in a significant decrease in the final packing density of *** decrease was attributed to the propagation of force chains throughout the *** significant decrease in final packing density with

关键词： Vibropacking Packing Densification Vibration Discrete element method Friction Wall friction Restitution

IgE-Mast cell mediated allergy: a sensor of food quality

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Signal Transduction and Targeted Therapy 2024年第1期9卷 8-9页

作者： christopher C.Udoye Rudolf A.Manz Institute for Systemic Inflammation Research University of LübeckLübeckGermany

In two recent studies published in Nature,Florsheim et *** Plum et *** that allergic-specific reactions induced by immunoglobulin(Ig)E mediated mast cell activation is crucial for the timely induction of antigen-avoidance behaviour.1,2 These studies prove the concept that allergic sensitization triggers the formation of avoidance behaviour and define the underlying molecular mechanism.

关键词： allergic mechanism

Enantioselective Synthesis,(Chir)optical Properties,and Postsynthetic Functionalization of Furan-Containing Oxa[5]-,Oxa[6]-,and Dioxa[6]helicenes

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CCS Chemistry 2024年第10期6卷 2439-2451页

作者： Wei Fu Valentina Pelliccioli Raquel Casares-lópez Juan M.Cuerva Martin Simon christopher Golz Manuel Alcarazo Institut für Organische und Biomolekulare Chemie Georg-August-Universität Göttingen37077 Göttingen Departamento de Química Orgánica Universidad de GranadaUnidad de Excelencia Química Aplicada a Biomedicina y MedioambienteE-18071 Granada

An expedient synthesis of a series of configurationally stable oxa[5]helicenes,oxa[6]helicenes,and dioxa[6]helicenes has been developed using an intramolecular,highly enantioselective,Au-catalyzed,alkyne hydroarylation *** absolute configuration of the newly prepared structures has been established by crystallography,their inversion barriers have been determined theoretically and experimentally,and their chiroptical properties have been *** of these data with those reported for thia-or carbohelicenes sharing an otherwise identical helical framework enables the establishment of comprehensive correlations between the nature of the embedded(hetero)atom(s)and the magnitude of these *** studies on the postsynthetic functionalization of the oxahelicenes obtained are also ***,siteselective bromination at the 15-position in oxa[5]helicene 5d allows its subsequent manipulation into pyridine-containing aza-oxa[7]helicene 13d;while the two termini of oxa[6]helicene 7d have been intramolecularly cyclised into the pleiadeno[1,12,11-bcde]benzofuran derivative 15d by acidic *** transformations take place without erosion of the enantiopurity.

关键词： Au-catalysis enantioselective synthesis oxa[n]helicenes racemization dynamics postsynthetic functionalization

Graphene-calcium carbonate coating to improve the degradation resistance and mechanical integrity of a biodegradable implant

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Journal of Magnesium and Alloys 2024年第1期12卷 394-404页

作者： lokesh Choudhary Parama Chakraborty Banerjee R.K.Singh Raman Derrek E.lobo christopher D.Easton Mainak Majumder Frank Witte Jörg F.löffler Department of Mechanical and Aerospace Engineering Monash UniversityClayton CampusMelbourneVIC 3800Australia Department of Chemical and Biological Engineering Monash UniversityClayton CampusMelbourneVIC 3800Australia Nanoscale Science and Engineering laboratory(NSEl) Bldg 37Monash UniversityClayton CampusMelbourneVIC 3800Australia CSIRO Materials Science and Engineering Bayview AvenueClaytonVIC 3168Australia Julius Wolff Institute and Berlin Brandenburg Center for Regenerative Therapies Charité–Universitätsmedizin BerlinAugustenburger Platz 113353 BerlinGermany laboratory of Metal Physics and Technology Department of MaterialsETH Zurich8093 ZurichSwitzerland

Biodegradable implants are critical for regenerative orthopaedic procedures,but they may suffer from too fast corrosion in human-body *** necessitates the synthesis of a suitable coating that may improve the corrosion resistance of these implants without compromising their mechanical *** this study,an AZ91 magnesium alloy,as a representative for a biodegradable Mg implant material,was modified with a thin reduced graphene oxide(RGO)-calcium carbonate(CaCO_(3))composite *** analytical and in-vitro electrochemical characterization reveals that this coating significantly improves the corrosion resistance and mechanical integrity,and thus has the potential to greatly extend the related application field.

关键词： Graphene coating Biodegradable implant Hydroxyapatite Corrosion Magnesium alloy

Functional mechanism study of the allelochemical myrigalone A identifies a group of ultrapotent inhibitors of ethylene biosynthesis in plants

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Plant Communications 2024年第6期5卷 246-262页

作者： George Heslop-Harrison Kazumi Nakabayashi Ana Espinosa-Ruiz Francesca Robertson Robert Baines christopher R.l.Thompson Katrin Hermann David Alabadí Gerhard leubner-Metzger Robin S.B.Williams Centre for Biomedical Sciences Department of Biological SciencesRoyal Holloway University of LondonEgham TW200EXUK Centre for Plant Molecular Sciences Department of Biological SciencesRoyal Holloway University of LondonEgham TW200EXUK Instituto de Biología Molecular y Celular de Plantas(CSIC-UPV) 46022 ValenciaSpain Centre for life’s Origins and Evolution Department of GeneticsEvolution and EnvironmentUniversity College LondonLondonUK Syngenta Crop Protection AGSteinSwitzerland

Allelochemicals represent a class of natural products released by plants as root,leaf,and fruit exudates that interfere with the growth and survival of neighboring *** how allelochemicals function to regulate plant responses may provide valuable new approaches to better control plant *** such allelochemical,Myrigalone A(MyA)produced by Myrica gale,inhibits seed germination and seedling growth through an unknown ***,we investigate MyA using the tractable modelDictyostelium discoideum and reveal that its activity depends on the conserved homolog of the plant ethylenesynthesis protein 1-aminocyclopropane-1-carboxylic acid oxidase(ACO).Furthermore,in silico modeling predicts the direct binding of MyA to ACO within the catalytic *** ***,ablation of ACO mimics the MyA-dependent developmental delay,which is partially restored by exogenous ethylene,and MyA reduces ethylene *** Arabidopsis thaliana,MyA treatment delays seed germination,and this effect is rescued by exogenous *** also mimics the effect of established ACO inhibitors on root and hypocotyl extension,blocks ethylenedependent root hair production,and reduces ethylene ***,in silico binding analyses identify a rangeof highlypotentethylene inhibitorsthatblock ethylene-dependent responseand reduce ethyleneproduction in ***,we demonstrate a molecular mechanism by which the allelochemical MyA reduces ethylene biosynthesis and identify a range of ultrapotent inhibitors of ethylene-regulated responses.

关键词： 1-aminocyclopropane-1-carboxylic acid ACC ACC oxidase ACO allelochemicals ethylene synthesis inhibitors structure-activity relationship

Are there sex-based disparities in cataract surgery?

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International Journal of Ophthalmology(English edition) 2024年第1期17卷 137-143页

作者： Matthew D.Geiger Anne M.lynch Alan G.Palestine Nathan C.Grove Karen l.christopher Richard S.Davidson Michael J.Taravella Naresh Mandava Jennifer l.Patnaik Department of Ophthalmology University of Colorado School of MedicineAuroraCO 80045USA

AIM:To investigate sex-based differences in the occurrence of intra-operative and post-operative complications and associated visual outcomes following cataract ***:This was a retrospective study of patients who had phacoemulsification cataract surgery at the University of Colorado School of *** collected included the patient’s health history,ocular comorbidities,operative and post-operative complications,and the post-operative best corrected visual acuity(BCVA).The data were analyzed using univariate and multivariable logistic regression with generalized estimating equations to account for the correlation of some patients having two eyes included in the ***:A total of 11977 eyes from 7253 patients were included in the *** comorbidities differed by sex,with males having significantly higher percentages of traumatic cataracts(males 0.7%vs females 0.1%),prior ocular surgery(6.7%vs 5.5%),and mature cataracts(2.8%vs 1.9%).Conversely,females had significantly higher rates of pseudoexfoliation(2.0%vs 3.2%).In unadjusted analysis,males had higher rates of posterior capsular rupture(0.8%vs 0.4%)and vitreous loss(1.0%vs 0.6%),but this difference was not significant after adjustment for *** had a significantly increased risk of post-operative retinal detachment,but in multivariable analysis this was no longer *** were significantly less likely to undergo post-operative neodymium-doped yttrium aluminum garnet(Nd:YAG)laser capsulotomy for posterior capsule opacification(OR=0.8,95%CI=0.7-0.9,P=0.0005).The BCVA was slightly worse for males pre-operatively;but post-operatively,both sexes exhibited similar visual acuity of Snellen equivalent 20/***:The study finds that in a cohort of patients presenting for cataract surgery,sex differences exist in pre-operative comorbidities and surgical characteristics that contribute to higher rates of some complications for ***,observed surgical complicatio

关键词： cataract surgery sex-based disparity phacoemulsification outcomes

How to establish an endoscopic bariatric practice

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World Journal of Gastrointestinal Endoscopy 2024年第4期16卷 178-186页

作者： Daniel B Maselli lauren l Donnangelo Brian Coan christopher E McGowan Clinical Research True You Weight LossAtlantaGA 30342United States Clinical Research True You Weight LossCaryNC 27513United States

Obesity is a chronic,progressive,and relapsing disease of excess adiposity that contributes to more than two hundred medical conditions and is projected to affect more than half the adult population of the United States by the year *** the limited penetrance of traditional bariatric surgery,as well as the cost and adherence barriers to anti-obesity medications,there is growing interest in the rapidly evolving field of endoscopic bariatric therapies(EBTs).EBTs are minimally invasive,same-day,per-oral endoscopic procedures and include endoscopic sleeve gastroplasty,intragastric balloons,and endoscopic bariatric revisional *** field represents an exciting and innovative subspe-cialty within ***,building a successful endoscopic bariatric practice requires intentional,coordinated,and sustained efforts to overcome the numerous obstacles to *** barriers include acquisition of the technical and cognitive skillset,practice limitations including the availability of nutrition counseling,facility capabilities,direct-to-consumer marketing,and financial pressures such as facility and anesthesia *** the highest-volume center for metabolic and bariatric endoscopy in the United States,we provide insights into successfully establishing an endoscopic bariatric program.

关键词： Obesity Endoscopic bariatric therapies Bariatric endoscopy Endoscopic sleeve gastroplasty Intragastric balloon Practice management

Dynamics of self-hybridized exciton–polaritons in 2D halide perovskites

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light(Science & Applications) 2024年第1期13卷 13-22页

作者： Surendra B.Anantharaman Jason lynch christopher E.Stevens christopher Munley Chentao li Jin Hou Hao Zhang Andrew Torma Thomas Darlington Francis Coen Kevin li Arka Majumdar PJames Schuck Aditya Mohite Hayk Harutyunyan Joshua R.Hendrickson Deep Jariwala Department of Electrical and Systems Engineering University of PennsylvaniaPhiladelphiaPA19104USA KBR Inc. BeavercreekOH45431USA Air Force Research laboratory Sensors DirectorateWright-Patterson Air Force BaseOH45433USA Department of Physics University of WashingtonSeattleWA98195USA Department of Physics Emory UniversityAtlantaGA30322USA Department of Chemical and Biomolecular Engineering Rice UniversityHoustonTX77005USA Department of Materials Science and Nanoengineering Rice UniversityHoustonTX77005USA Applied Physics Program Smalley‐Curl InstituteRice UniversityHoustonTX77005USA Department of Mechanical Engineering Columbia UniversityNew YorkNY10027USA Department of Electrical and Computer Engineering University of WashingtonSeattleWA98195USA

Excitons,bound electron–hole pairs,in two-dimensional hybrid organic inorganic perovskites(2D HOIPs)are capable of forming hybrid light-matter states known as exciton-polaritons(E–Ps)when the excitonic medium is confined in an optical *** the case of 2D HOIPs,they can self-hybridize into E–Ps at specific thicknesses of the HOIP crystals that form a resonant optical cavity with the ***,the fundamental properties of these self-hybridized E–Ps in 2D HOIPs,including their role in ultrafast energy and/or charge transfer at interfaces,remain ***,we demonstrate that>0.5µm thick 2D HOIP crystals on Au substrates are capable of supporting multiple-orders of self-hybridized E–P *** E–Ps have high Q factors(>100)and modulate the optical dispersion for the crystal to enhance sub-gap absorption and *** varying excitation energy and ultrafast measurements,we also confirm energy transfer from higher energy E–Ps to lower energy E–***,we also demonstrate that E–Ps are capable of charge transport and transfer at *** findings provide new insights into charge and energy transfer in E–Ps opening new opportunities towards their manipulation for polaritonic devices.

关键词： charge polar excitation

Deterministic epidemic models overestimate the basic reproduction number of observed outbreaks

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Infectious Disease Modelling 2024年第3期9卷 680-688页

作者： Wajid Ali christopher E.Overton Robert R.Wilkinson Kieran J.Sharkey Department of Mathematical Sciences University of LiverpoolPeach StreetLiverpoolL697ZXEnglandUnited Kingdom Department of Applied Mathematics Liverpool John Moores UniversityByrom StreetLiverpoolL35UXEnglandUnited Kingdom

The basic reproduction number,R_(0),is a well-known quantifier of epidemic ***,a class of existing methods for estimating R_(0)from incidence data early in the epidemic can lead to an over-estimation of this *** particular,when fitting deterministic models to estimate the rate of spread,we do not account for the stochastic nature of epidemics and that,given the same system,some outbreaks may lead to epidemics and some may ***,an observed epidemic that we wish to control is a major *** amounts to implicit selection for major outbreaks which leads to the over-estimation *** formally characterised the split between major and minor outbreaks by using Otsu's method which provides us with a working *** show that by conditioning a‘deterministic’model on major outbreaks,we can more reliably estimate the basic reproduction number from an observed epidemic trajectory.

关键词： Estimating R_(0) Simple birth-death process Major outbreak Conditioned epidemic Stochastic fade-out