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Converting TREx-RGB green-channel data to 557.7 nm auroral intensity:Methodology and initial results

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Earth and Planetary Physics 2024年第1期8卷 258-274页

作者： Jun Liang D.M.Gillies E.Spanswick E.F.Donovan University of Calgary CalgaryT2N 1N4Canada

The recently deployed Transition Region Explorer(TREx)-RGB(red-green-blue)all-sky imager(ASI)is designed to capture“true color”images of the aurora and *** the 557.7 nm green line is usually the brightest emission line in visible auroras,the green channel of a TREx-RGB camera is usually dominated by the 557.7 nm *** this rationale,the TREx mission does not include a specific 557.7 nm imager and is designed to use the RGB green-channel data as a proxy for the 557.7 nm *** this study,we present an initial effort to establish the conversion ratio or formula linking the RGB green-channel data to the absolute intensity of 557.7 nm auroras,which is crucial for quantitative uses of the RGB *** illustrate two approaches:(1)through a comparison with the collocated measurement of green-line auroras from the TREx spectrograph,and(2)through a comparison with the modeled green-line intensity according to realistic electron precipitation flux measurements from low-Earth-orbit satellites,with the aid of an auroral transport *** demonstrate the procedures and provide initial results for the TREx-RGB ASIs at the Rabbit Lake and Lucky Lake *** RGB response is found to be *** conversion ratios or formulas between RGB green-channel data and the green-line auroral intensity are given and can be applied immediately by TREx-RGB data *** methodology established in this study will also be applicable to the upcoming SMILE ASI mission,which will adopt a similar RGB camera system in its deployment.

关键词： TREx RGB green-line aurora auroral transport model

Distributed phase-matching measurement for dynamic strain and temperature sensing based on stimulated Brillouin scattering enhanced four-wave mixing

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Photonics Research 2024年第1期12卷 141-153页

作者： YUAn WAnG PEDRO TOVAR JUnTOnG YAnG LIAnG CHEn XIAOYI BAO nexus for Quantum Technologies University of OttawaOttawaOntario K1N 6N5Canada

A Brillouin dynamic grating(BDG) can be used for distributed birefringence measurement in optical fibers,offering high sensitivity and spatial resolution for sensing ***,it is quite a challenge to simultaneously achieve dynamic measurements with both high accuracy and high spatial *** this work,we propose a sensing mechanism to achieve distributed phase-matching measurement using a chirped pulse as a probe *** BDG reflection,the peak reflection corresponds to the highest four-wave mixing(FWM) conversion efficiency,and it requires the Brillouin frequency in the fast and slow axes to be equal,which is called the phase-matching *** condition changes at different fiber positions,which requires a range of frequency injection for the probe *** proposed method uses a chirped pulse as a probe wave to cover this frequency range associated with distributed birefringence *** allows us to detect distributed phase matching for birefringence changes that are introduced by temperature and strain *** to the single shot and direct time delay measurement capability,the acquisition rate in our system is only limited by the fiber ***,unlike conventional BDG spectrum recovery-based systems,the spatial resolution here is determined by both the frequency chirping rate of the probe pulse and the birefringence profile of the *** the experiments,an acquisition rate of 1 k Hz(up to fiber length limits) and a spatial resolution of 10 cm using a 20 ns probe pulse width are *** minimum detectable temperature and strain variation are 5.6 mK and 0.37 με along a 2 km long polarization-maintaining fiber(PMF).

关键词： fiber scattering polarization

PRECOnDITIOnED SPECTRAL PROJECTED GRADIEnT METHOD On COnVEX SETS

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Journal of Computational Mathematics 2005年第3期23卷 225-232页

作者： LenysBello MarcosRaydan dpto.deMatemdtica FacultaddeCiencias(FACYT)UniversidaddeCaraboboValenciaVenezuela dpto.decomputación UniversidadCentraldeVenezuelaAp.47002Caracas1041-AVenezuela

The spectral gradient method has proved to be effective for solving large-scale unconstrained optimization problems. It has been recently extended and combined with the projected gradient method for solving optimization problems on convex sets. This combination includes the use of nonmonotone line search techniques to preserve the fast local convergence. In this work we further extend the spectral choice of steplength to accept preconditioned directions when a good preconditioner is available. We present an algorithmthat combines the spectral projected gradient method with preconditioning strategies toincrease the local speed of convergence while keeping the global properties. We discuss implementation details for solving large-scale problems.

关键词： Spectral gradient method Projected gradient method Preconditioning tech-niques nonmonotone line search

From the mathematical model to the patient: The scientific and human aspects of artificial intelligence in gastrointestinal surgery

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World Journal of Gastrointestinal Surgery 2024年第6期16卷 1517-1520页

作者： Javier Arredondo Montero Department of Pediatric Surgery Complejo Asistencial Universitario de LeónCastilla y LeónLeón 24008Spain

Recent medical literature shows that the application of artificial intelligence(AI)models in gastrointestinal pathology is an exponentially growing field,with pro-mising models that show very high *** inflammatory bowel disease(IBD),recent reviews demonstrate promising diagnostic and prognostic AI ***,studies are generally at high risk of bias(especially in AI models that are image-based).The creation of specific AI models that improve diagnostic performance and allow the establishment of a general prognostic fo-recast in IBD is of great interest,as it may allow the stratification of patients into subgroups and,in turn,allow the creation of different diagnostic and therapeutic protocols for these *** surgical models,predictive models of post-operative complications have shown great potential in large-scale *** this work,the authors present the development of a predictive algorithm for early post-surgical complications in Crohn's disease based on a Random Forest model with exceptional predictive ability for complications within the *** pre-sent work,based on logical and reasoned,clinical,and applicable aspects,lays a solid foundation for future prospective work to further develop post-surgical prognostic tools for *** next step is to develop in a prospective and mul-ticenter way,a collaborative path to optimize this line of research and make it applicable to our patients.

关键词： Survivor bias Data analysis Machine learning Ethics Critical thinking Postsurgical Complications Inflammatory bowel disease Gastrointestinal surgery

Dominance of transposable element‑related satDnAs results in great complexity of“satDnA library”and invokes the extension towards“repetitive DnA library”

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Marine Life Science & Technology 2024年第2期6卷 236-251页

作者： Monika Tunjić‑Cvitanić Daniel García‑Souto Juan J.Pasantes EvaŠatović‑Vukšić Division of Molecular Biology Ruđer BoškovićInstitute10000 ZagrebCroatia Genomes and Disease Centre for Research in Molecular Medicine and Chronic Diseases(CIMUS)Universidade de Santiago de Compostela15706 Santiago de CompostelaSpain Department of Zoology Genetics and Physical AnthropologyUniversidade de Santiago de Compostela15706 Santiago de CompostelaSpain Centro de Investigación Mariña Dpto de BioquímicaXenética e InmunoloxíaUniversidade de Vigo36310 VigoSpain

Research on bivalves is fast-growing,including genome-wide analyses and genome *** characteristics qualify oysters as a valuable model to explore repetitive DnA sequences and their genome *** we char-acterize the satellitomes of five species in the family Ostreidae(Crassostrea angulata,***,***,***,Ostrea edulis),revealing a substantial number of satellite DnAs(satDnAs)per genome(ranging between 33 and 61)and peculiarities in the composition of their *** satDnAs were either associated to or derived from transposable elements,displaying a scarcity of transposable element-unrelated satDnAs in these *** to the non-conventional satellitome constitution and dominance of Helitron-associated satDnAs,comparative satellitomics demanded more in-depth analyses than standardly *** analyses(including ***,the first bivalve species with a defined satellitome)revealed that 13 satDnAs occur in all six oyster genomes,with Cg170/HindIII satDnA being the most abundant in all of *** the“satDnA library model”highlighted the necessity to adjust this term when studying tandem repeat evolution in organisms with such *** repetitive sequences with potential variation in the organizational form and repeat-type affiliation are examined across related species,the introduction of the terms“TE library”and“repetitive DnA library”becomes essential.

关键词： Satellitome Comparative satellitomics Helitron Bivalves “Dark matter of the genome”

Early diagnosis of pancreatic cancer: Shedding light on an unresolved challenge

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World Journal of Clinical Cases 2024年第14期12卷 2463-2465页

作者： Cristian Lindner Department of Radiology Faculty of MedicineUniversity of ConcepciónConcepción 4030000Chile

Diagnosing early-stage pancreatic cancer(PC)remains a clinical ***,studying novel imaging aspects that could enhance the diagnostic accuracy of malignant pancreatic precursor lesions is *** article aims to un-derscore the promising role of emerging imaging aspects that may facilitate the earlier diagnosis of PC,thereby improving its management and prognosis.

关键词： Pancreatic cancer Pancreatic intraepithelial neoplasm High-grade pancreatic intraepithelial neoplasm Pancreatic ducts Cancer Early diagnosis

Imaging features of malignant vs stone-induced biliary obstruction:Aspects to consider

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World Journal of Clinical Cases 2024年第15期12卷 2678-2681页

作者： Cristian Lindner Department of Radiology Faculty of MedicineUniversity of ConcepciónConcepción 4030000Chile

Radiological studies play a crucial role in the evaluation of patients with biliary duct obstruction,allowing for the guidance of clinical diagnosis towards a malignant or stone-induced etiology through the recognition of relevant imaging features,which must be continuously revisited given their prognostic *** article aims to emphasize the importance of recognizing crucial imaging aspects of malignant and stone-induced biliary obstruction.

关键词： Malignant biliary obstruction Choledocholithiasis Dilated bile ducts Magnetic resonance Multidetector computed tomography

Photosynthetic Gas Exchange and nitrogen Assimilation in Green Bean Plants Supplied with Two Sources of Silicon

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Phyton-International Journal of Experimental Botany 2024年第5期93卷 963-980页

作者： Julio C.Anchondo-Páez Esteban Sánchez Carlos A.Ramírez-Estrada Alondra Salcido-Martínez Erick H.Ochoa-Chaparro Department of Plant Physiology Centro de Investigación en Alimentación y DesarrolloCiudad Delicias33089México

Beans contain a wide range of vitamins,proteins,calcium,and zinc which make them an important food source for many *** meet the demand for bean production worldwide,large amounts of fertilizers and pesticides are ***,the cost of production and environmental impact *** produce food sustainably,the use of beneficial nutrients such as silicon as a biostimulant has been ***,information about the effect of different sources of silicon on the metabolism of bean plants is *** plants *** were grown in pots for 60 days and the effect of foliar application of silicon nanoparticles and the silicon-based biostimulant Codasilat 4 concentrations(0,1,2,and 4 mM)on total biomass,yield,photosynthetic pigment concentration,photosynthetic activity,stomatal conductance,transpiration rate,chlorophyll fluorescence,and nitrogen assimilation were *** results obtained showed that the supply of silicon at a dose of 1 mM functioned as a biostimulant,favoring gas exchange and nitrogen assimilation within the plant,which stimulated growth and *** results of this research work allowed a better comprehension of the effects of silicon application through silicon nanoparticles and the biostimulant Codasilon the physiology of green bean plants.

关键词： nanoparticles silicon Phaseolus vulgaris L.

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