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Nanomanufacturing and Metrology 2022年第1期5卷 60-66页

作者： Nathan black David Edwards Niall browne Joseph G.M.Guy Niyorjyoti Sharma Kristina M・Holsgrove aaron b.naden Raymond G.P.McQuaid brian J.Rodriguez Amit Kumar School of Maths and Physics Queen's University BelfastBelfast BT7 INNUK School of Chemistry University of St.AndrewsSt Andrews KY169STUK School of Physics University College DublinBelfieldDublin 4Ireland

The realization of a mixed-phase microstructure in strained biFeO_(3)(bFO)thin films has led to numerous novel effects derived from the coexistence of the tetragonal-like monoclinic phase(T phase)and rhombohedral-like monoclinic phase(R phase).Strong strain and polarization diiferences between the phases should result in a high level of transformation plasticity,which enables the continuous alteration of the relative proportion of R and T states in response to external forces.Although the potential for utilizing such plasticity to control mixed-phase populations under external stimuli is evident,direct experi・mental evidence backed by equilibrium predictions has not yet been fully demonstrated.Here we demonstrate deterministic control of mixed-phase populations in an epitaxially strained bFO thin film through the application of localized stresses and electric fields in a reversible manne匚The results illustrate and rationalize deterministic control of mixed phases in strained bFO films,which could be crucial in tuning their functional properties.The findings also highlight a new multiparametric technique in the scanning probe lithography toolbox based on tip-assisted electric and strain field manipulation of functional properties that might find application beyond the ferroelectric domain and structural phase lithography.

关键词： Phase competition Ferroelectric Stress Lithography

Evaluation of a hepatic biomarker of nutritional imbalance in juvenile red drum(Sciaenops ocellatus) fed 60% soybean meal-based diets using NMR-based metabolomics

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Animal Nutrition 2024年第1期16卷 45-61页

作者： Fabio Casu aaron M.Watson Justin Yost T.Gibson Gaylord Daniel W.bearden Michael R.Denson Marine Resources Research Institute South Carolina Department of Natural Resources bozeman Fish Technology Center United States Fish and Wildlife Service Marine biochemical Sciences Group Chemical Sciences Division National Institute of Standards and Technology Hollings Marine Laboratory

A 12-week feeding trial with juvenile red drum(Sciaenops ocellatus) fed high-soybean meal(SbM) diets was conducted to investigate a putative biomarker of nutritional imbalance, N-formimino-L-glutamate(FIGLU). Three fishmeal-free, 60% SbM pelleted diets(named b12, Fol, and Met, respectively) were tested to evaluate the effects on growth performance and tissue metabolite profiles of supplementation of vitamin b12(0.012 mg/kg), folate(10 mg/kg), methionine(1 g/kg) respectively, above basal supplementation levels. A fourth SbM-based diet(named b12/Fol/Met) was formulated with a combination of b12, folate, and methionine to attain the above-mentioned target concentrations. A fifth 60% SbM diet(named FWS) with methionine supplementation(1 g/kg above basal supplementation levels), enriched with taurine, lysine and threonine as well as minerals, was also tested. This diet contained formulation targets and additives which have allowed for replacing fishmeal with plant proteins in rainbow trout feeds. Control diets included a fishmeal-based diet(named FM), an unsupplemented basal 60% SbM diet(named SbM60), and a “natural” diet(named N) made up of equal parts of fish(cigar minnows), squid and shrimp as a positive reference for growth performance. Formulated feeds contained approximately 37% total crude protein, approximately 14% total crude lipid and were energetically balanced. Standard growth performance metrics were measured, and tissues(liver, muscle) were collected at week 12 to evaluate diet-induced metabolic changes using nuclear magnetic resonance(NMR)-based metabolomics.Our results show that the FWS diet outperformed all other SbM diets and the FM diet under all performance metrics(Pbut was detected in those fed the SbM diets and the FM diet. Fish fed the FWS diet and the Met diet showed lower hepatic levels of FIGLU compared with the other SbM-based diets(P<0.05), suggesting that among the different supplementation regimes, methionine supplementation was associ

关键词： Aquaculture Metabolomics Nuclear magnetic resonance Red drum Soybean meal N-Formimino-L-glutamate

Aerosol jet printing of surface acoustic wave microfluidic devices

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Microsystems & Nanoengineering 2024年第1期10卷 231-242页

作者： Joseph Rich brian Cole Teng Li brandon Lu Hanyu Fu brittany N.Smith Jianping Xia Shujie Yang Ruoyu Zhong James L.Doherty Kanji Kaneko Hiroaki Suzuki Zhenhua Tian aaron D.Franklin Tony Jun Huang Department of biomedical Engineering Duke UniversityDurhamNC 27708USA Department of Electrical and Computer Engineering Duke UniversityDurhamNC 27708USA Department of Mechanical Engineering Virginia Polytechnic Institute and State UniversityBlacksburgVA 24061USA Thomas Lord Department of Mechanical Engineering and Materials Science Duke UniversityDurhamNC 27708USA Deptartment of Precision Mechanics Faculty of Science and EngineeringChuo UniversityTokyo 112-8551Japan Department of Chemistry Duke UniversityDurhamNC 27708USA

The addition of surface acoustic wave(SAW)technologies to microfluidics has greatly advanced lab-on-a-chip applications due to their unique and powerful attributes,including high-precision manipulation,versatility,integrability,biocompatibility,contactless nature,and rapid actuation.However,the development of SAW microfluidic devices is limited by complex and time-consuming micro/nanofabrication techniques and access to cleanroom facilities for multistep photolithography and vacuum-based processing.To simplify the fabrication of SAW microfluidic devices with customizable dimensions and functions,we utilized the additive manufacturing technique of aerosol jet printing.We successfully fabricated customized SAW microfluidic devices of varying materials,including silver nanowires,graphene,and poly(3,4-ethylenedioxythiophene)polystyrene sulfonate(PEDOT:PSS).To characterize and compare the acoustic actuation performance of these aerosol jet printed SAW microfluidic devices with their cleanroom-fabricated counterparts,the wave displacements and resonant frequencies of the different fabricated devices were directly measured through scanning laser Doppler vibrometry.Finally,to exhibit the capability of the aerosol jet printed devices for lab-on-a-chip applications,we successfully conducted acoustic streaming and particle concentration experiments.Overall,we demonstrated a novel solution-based,direct-write,single-step,cleanroom-free additive manufacturing technique to rapidly develop SAW microfluidic devices that shows viability for applications in the fields of biology,chemistry,engineering,and medicine.

关键词： printing wave fluid

Viral hepatitis in 2021:The challenges remaining and how we should tackle them

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World Journal of Gastroenterology 2022年第1期28卷 76-95页

作者： Rebecca Dunn aaron Wetten Stuart McPherson Mhairi C Donnelly Gastroenterology University Hospital of North TeesStockton on Tees TS198PEUnited Kingdom Liver Unit Freeman HospitalNewcastle NE77DNUnited Kingdom Translational and Clinical Research Institute Newcastle UniversityNewcastle NE17RUUnited Kingdom

Viral hepatitis results in 1.4 million deaths annually.The World Health Organization(WHO)set an ambitious target to eliminate viral hepatitis by 2030,but significant challenges remain.These include inequalities in access to healthcare,reaching at risk populations and providing access to screening and effective treatment.Stigma around viral hepatitis persists and must be addressed.The WHO goal of global elimination by 2030 is a worthy aim,but remains ambitious and the coronavirus 2019 pandemic undoubtedly has set back progress.This review article will focus on hepatitis A to E,highlighting problems that have been resolved in the field over the past decade,those that remain to be resolved and suggest directions for future problem solving and research.

关键词： Hepatitis A Hepatitis b Hepatitis C Hepatitis D Hepatitis E COVID-19

A data directory to facilitate investigations on worldwide wildlife trafficking

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big Earth Data 2023年第2期7卷 338-348页

作者： Meredith L.Gore Rowan Hilend Jonathan OPrell Emily Griffin John R.Macdonald burcu b.Keskin aaron Ferber bistra Dilkina Department of Geographical Sciences University of MarylandCollege ParkUSA Department of Supply Chain Management Michigan State UniversityEast LansingUSA Department of Information Sciences Statisticsand Management ScienceUniversity of AlabamaTuscaloosaUSA Operations and Information Management Division Babson CollegeWellesleyUSA Supply Chain Management Department of ManagementColorado State UniversityFort CollinsUSA Verterbi School of Engineering University of Southern CaliforniaLos AngelesUSA

Wildlife trafficking is a global phenomenon posing many negative impacts on socio-environmental systems.Scientific exploration of wildlife trafficking trends and the impact of interventions is significantly encumbered by a suite of data reuse challenges.We describe a novel,open-access data directory on wildlife trafficking and a corresponding visualization tool that can be used to identify data for multiple purposes,such as exploring wildlife trafficking hotspots and convergence points with other crime,discovering key drivers or deterrents of wildlife trafficking,and uncovering structural patterns.Keyword searches,expert elicitation,and peer-reviewed publications were used to search for extant sources used by industry and non-profit organizations,as well as those leveraged to publish academic research articles.The open-access data directory is designed to be a living document and searchable according to multiple measures.The directory can be instrumental in the data-driven analysis of unsustainable illegal wildlife trade,supply chain structure via link prediction models,the value of demand and supply reduction initiatives via multi-item knapsack problems,or trafficking behavior and transportation choices via network interdiction problems.

关键词： Illegal wildlife trade supply chain operations management interdiction conservation

Can a multistage approach improve individual tree mortality predictions across the complex mixed-species and managed forests of eastern North America?

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Forest Ecosystems 2023年第1期10卷 21-30页

作者： Cen Chen John Kershaw Jr aaron Weiskittel Elizabeth McGarrigle Center for Research on Sustainable Forests University of MaineOronoME04469USA Faculty of Forestry&Environmental Management University of New BrunswickFrederictonNBE3B 5A3Canada Nova Scotia Department of Natural Resources HalifaxNSB3J 3M8Canada

Tree mortality plays a fundamental role in the dynamics of forest ecosystems,yet it is one of the most difficult phenomena to accurately predict.Various modeling strategies have been developed to improve individual tree mortality predictions.One less explored strategy is the use of a multistage modeling approach.Potential improvements from this approach have remained largely unknown.In this study,we developed a novel multistage approach and compared its performance in individual tree mortality predictions with a more conventional approach using an identical individual tree mortality model formulation.Extensive permanent plot data(n=9442)covering the Acadian Region of North America and over multiple decades(1965–2014)were used in this study.Our results indicated that the model behavior with the multistage approach better depicted the observed mortality and showed a notable improvement over the conventional approach.The difference between the observed and predicted numbers of dead trees using the multistage approach was much smaller when compared with the conventional approach.In addition,tree survival probabilities predicted by the multistage approach generally were not significantly different from the observations,whereas the conventional approach consistently underestimated mortality across species and overestimated tree survival probabilities over the large range of DbH in the data.The new multistage approach also predictions of zero mortality in individual plots,a result not possible in conventional models.Finally,the new approach was more tolerant of modeling errors because it based estimates on ranked tree mortality rather than error-prone predicted values.Overall,this new multistage approach deserves to be considered and tested in future studies.

关键词： Tree mortality modeling Mortality disaggregation Mixed effect model Annualization Mixed forests

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Importance of being Nernst: Synaptic activity and functional relevance in stem cell-derived neurons

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World Journal of Stem Cells 2015年第6期7卷 899-921页

作者： aaron b bradford Patrick M McNutt Cell/Molecular biology branch US Army Medical Research Institute of Chemical DefenseAberdeen Proving Grounds-EAMD 21010United States

Functional synaptogenesis and network emergence are signature endpoints of neurogenesis. These behaviors provide higher-order confirmation that biochemical and cellular processes necessary for neurotransmitter release, post-synaptic detection and network propagationof neuronal activity have been properly expressed and coordinated among cells. The development of synaptic neurotransmission can therefore be considered a defining property of neurons. Although dissociated primary neuron cultures readily form functioning synapses and network behaviors in vitro, continuously cultured neurogenic cell lines have historically failed to meet these criteria. Therefore, in vitro-derived neuron models that develop synaptic transmission are critically needed for a wide array of studies, including molecular neuroscience, developmental neurogenesis, disease research and neurotoxicology. Over the last decade, neurons derived from various stem cell lines have shown varying ability to develop into functionally mature neurons. In this review, we will discuss the neurogenic potential of various stem cells populations, addressing strengths and weaknesses of each, with particular attention to the emergence of functional behaviors. We will propose methods to functionally characterize new stem cell-derived neuron(SCN) platforms to improve their reliability as physiological relevant models. Finally, we will review how synaptically active SCNs can be applied to accelerate research in a variety of areas. Ultimately, emphasizing the critical importance of synaptic activity and network responses as a marker of neuronal maturation is anticipated to result in in vitro findings that better translate to efficacious clinical treatments.

关键词： Synapses Neurotransmission In vitrotechniques Induced pluripotent stem cells Neuronalnetworks Neurogenesis Neural stem cells Embryonicstem cells Induced neurons

Activation of PXR causes drug interactions with Paxlovid in transgenic mice

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Acta Pharmaceutica Sinica b 2023年第11期13卷 4502-4510页

作者： Saifei Lei Alice Guo Jie Lu Qian Qi aaron S.Devanathan Junjie Zhu Xiaochao Ma Center for Pharmacogenetics Department of Pharmaceutical SciencesSchool of PharmacyUniversity of PittsburghPittsburghPA 15261USA School of Nursing University of PennsylvaniaPhiladelphiaPA 19104USA Department of Pharmacy and Therapeutics School of PharmacyUniversity of PittsburghPittsburghPA 15261USA

Paxlovid is a nirmatrelvir(NMV)and ritonavir(RTV)co-packaged medication used for the treatment of coronavirus disease 2019(COVID-19).The active component of Paxlovid is NMV and RTV is a pharmacokinetic booster.Our work aimed to investigate the drug/herb-drug interactions associated with Paxlovid and provide mechanism-based guidance for the clinical use of Paxlovid.by using recombinant human cytochrome P450s(CYPs),we confirmed that CYP3A4 and 3A5 are the major enzymes responsible for NMV metabolism.The role of CYP3A in Paxlovid metabolism were further verified in Cyp3a-null mice,which showed that the deficiency of CYP3A significantly suppressed the metabolism of NMV and RTV.Pregnane X receptor(PXR)is a ligand-dependent transcription factor that upregulates CYP3A4/5 expression.We next explored the impact of drug-and herb-mediated PXR activation on Paxlovid metabolism in a transgenic mouse model expressing human PXR and CYP3A4/5.We found that PXR activation increased CYP3A4/5 expression,accelerated NMV metabolism,and reduced the systemic exposure of NMV.In summary,our work demonstrated that PXR activation can cause drug interactions with Paxlovid,suggesting that PXR-activating drugs and herbs should be used cautiously in COVID-19 patients receiving Paxlovid.

关键词： Paxlovid Nirmatrelvir Ritonavir Pregnane X receptor CYP3A4/5 Rifampicin Rhynchophylline Drug/herb-drug interactions

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Evaluation and management of inherited disorders of surfactant metabolism

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Chinese Medical Journal 2010年第20期123卷 2943-2947页

作者： aaron Hamvas Edward Mallinckrodt Department of Pediatrics Washington University School of Medicine and St. Louis Children's Hospital St. Louis Missouri 63110 USA

Objective To review the pathophysiology, evaluation, management, and outcomes of children with inherited disorders of surfactant metabolism due to mutations in the genes encoding surfactant proteins-b or -C（SFTPb, SFTPC）, ATP binding cassette member A3 （AbCA3）, and thyroid transcription factor （NKX2.1）.Data sources Review of the literature, previous work from the author＇s and collaborators＇ laboratories, St. Louis Children＇s Hospital Lung Transplant Database.Study selection Key articles in the field, author＇s work.Results Inherited disorders of surfactant metabolism present as acute, severe respiratory dysfunction in the neonatal period （SFTPb, AbCA3, NKX2.1） or as chronic respiratory insufficiency in later infancy and childhood which is of variable onset, severity, and course （SFTPC, AbCA3, NKX2.1）. Diagnosis is established with sequencing the relevant genes; lung biopsy with electron microscopy is a useful adjunct. For surfactant protein-b and AbCA3 deficiency presenting with acute neonatal disease, treatment options are limited to lung transplantation or compassionate care. For the more chronic presentations of surfactant protein-C, AbCA3, and NKX2.1 associated disease, the natural history is variable and therefore individualized, supportive care is appropriate,Conclusions Inherited disorders of surfactant metabolism are rare, but informative diseases that provide unique opportunities for understanding mechanisms of respiratory disease in newborns and children.

关键词： respiratory distress syndrome newborn genetics lung transplantation

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Application of Hausdorff fractal derivative to the determination of the vertical sediment concentration distribution

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International Journal of Sediment Research 2023年第1期38卷 12-23页

作者： Hongguang Sun Shiqian Nie aaron I.Packman Yong Zhang Dong Chen Chengpeng Lu Chunmiao Zheng State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University College of Mechanics and Materials Hohai University College of Mathematics and Systems Science Shandong University of Science and Technology Department of Civil and Environmental Engineering Northwestern University Department of Geological Sciences University of Alabama Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences College of Hydrology and Water Resources Hohai University School of Environmental Science and Engineering Southern University of Science and Technology

The Rouse formula and its variants have been widely used to calculate the steady-state vertical concentration distribution for suspended sediment in steady sediment-laden flows, where the diffusive flux is assumed to be Fickian. Turbulent flow, however, exhibits fractal properties, leading to non-Fickian diffusive flux for sediment particles. To characterize non-Fickian dynamics of suspended sediment, the current study proposes a Hausdorff fractal derivative based advection-dispersion equation(HADE)model, where the Fickian diffusive flux in the Rouse model is replaced by a fractal derivative re-scaled using a constant diffusivity. The order of the Hausdorff fractal derivative is designed to characterize the influence of the multi-fractal turbulence structure on sediment diffusion. Applications show that the HADE model, with the analytical solution expressed using a stretched exponential function, can accurately describe the observed vertical concentration profiles for suspended sediment with different sizes.This improvement well captures the non-exponential decay of the vertical sediment concentration in turbulent flow. Further analyses of measured sediment concentration profiles reveal that the Hausdorff fractal order decreases with the Rouse parameter, which describes the stronger impact of turbulent flow and a more uniform sediment concentration profile for smaller particles. Model comparisons also show that the HADE model provides better performance in describing the sediment concentration profiles than the improved Rouse formula and the standard fractional derivative advection-dispersion equation(FADE), which either under-or over-estimates vertical displacement of sediment particles, likely due to coherent turbulent structures.

关键词： Anomalous diffusion Hausdorff fractal derivative Vertical concentration distribution Suspended sediment Metric transform