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Analysis of ancient mass extinction recoveries in marine environments: generating strategies for managing outcomes of the current mass extinction

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National Science Review 2024年第1期11卷 8-10页

作者： david j.Bottjer Department of Earth Sciences University of Southern California

the defining feature of a mass extinction and its associated recovery is the global amount of extinction that occurred[1]. However, there is finer-scale detail to the story, as seen in the ongoing modern mass extinction(the sixth mass extinction), which exhibits variable effects among marine ecosystems and environments, and hence geographic areas [1].

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Enhancing diabetic retinopathy screening:Non-mydriatic fundus photography-assisted telemedicine for improved clinical management

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World journal of Diabetes 2024年第8期15卷 1820-1823页

作者： Kira j Szulborski david j Ramsey Department of Ophthalmology Tufts University School of MedicineBostonMA 02111United States Lahey Department of Surgery Division of OphthalmologyUMass Chan Medical SchoolUniversity of MassachusettsBurlingtonMA 01805United States Graduate Faculty New England College of OptometryBostonMA 02115United States

the utilization of non-mydriatic fundus photography-assisted telemedicine to screen patients with diabetes mellitus for diabetic retinopathy provides an accurate,efficient,and cost-effective method to improve early detection of *** has also been shown to correlate with increased participation of patients in other aspects of diabetes *** particular,patients who undergo teleretinal imaging are more likely to meet Comprehensive Diabetes Care Healthcare Effectiveness Data and Information Set metrics,which are linked to preservation of quality-adjusted life years and additional downstream healthcare savings.

关键词： Diabetes Diabetic retinopathy telemedicine tele-ophthalmology Nonmydriatic fundus photography-assisted telemedicine Vision screening Preventative health services Health policy

In situ characterization of particle formation in spray flame synthesis using wide-angle light scattering

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Particuology 2024年第3期86卷 304-312页

作者： Simon Aβmann Franz j.t.Huber Stefan Will Lehrstuhl für technische thermodynamik(Ltt) Friedrich-Alexander-Universitat Erlangen-Nürnberg(FAU)Erlangen91058Germany Erlangen Graduate Schoolin Advanced Optical technologies(SAOt) Friedrich-Alexander-Universitat Erlangen-Nurnberg(FAU)Erlangen91052Germany Competence Unit Engineering of Advanced Materials(EAM) Friedrich-Alexander-Universitat Erlangen-Nürnberg(FAU)Erlangen91052Germany

Wide-angle light scattering(WALS)was used for in situ measurements of droplet and nanoparticle size distributions during the synthesis of titania and iron oxide particles from liquid precursor solutions in the standardized SpraySyn burner for spray flame *** was synthesized from titanium tetraisopropoxide(ttIP)and iron oxide from iron(II)nitrate nonahydrate(INN)using ethanol(EtOH)as *** images were taken at heights up to 120 mm above the burner surface and classified into droplet and particle *** size distributions were derived from a sequential analysis of scattering data containing the oscillating Mie pattern,the lognormal size distribution parameters for spherical and fractal particle fractions from a multivariate approach on averaged particle scattering *** results show that the precursor addition leads to altered evaporation behavior and even droplet disruption probably induced by puffing or micro-explosions compared to pure *** the case of ttIP(a hygroscopic alkoxide),the synthesis of a large fraction of spheres was observed,while the nitrate INN leads to the formation of mostly fractal aggregates.

关键词： Spray flame synthesis Metal oxide particles Elastic light scattering Droplet size distribution Nanoparticle morphology Particle size distribution

Single-atom Pt on carbon nanotubes for selective electrocatalysis

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Carbon Energy 2024年第1期6卷 63-71页

作者： Samuel S.Hardisty Xiaoqian Lin Anthony R.j.Kucernak david Zitoun Department of Chemistry Bar Ilan Institute of Nanotechnology and Advanced Materials(BINA)Bar Ilan UniversityRamat GanIsrael Department of Chemistry Molecular Science Research HubImperial College LondonLondonUK

Utilizing supported single atoms as catalysts presents an opportunity to reduce the usage of critical raw materials such as platinum,which are essential for electrochemical reactions such as hydrogen oxidation reaction(HOR).Herein,we describe the synthesis of a Pt single electrocatalyst inside single-walled carbon nanotubes(SWCNts)via a redox *** via electron microscopy,X-ray photoelectron microscopy,and X-ray absorption spectroscopy show the single-atom nature of the *** electrochemical behavior of the sample to hydrogen and oxygen was investigated using the advanced floating electrode technique,which minimizes mass transport limitations and gives a thorough insight into the activity of the *** single-atom samples showed higher HOR activity than state-of-the-art 30%Pt/C while almost no oxygen reduction reaction activity in the proton exchange membrane fuel cell operating *** selective activity toward HOR arose as the main fingerprint of the catalyst confinement in the SWCNts.

关键词： confinement electrocatalysis hydrogen platinum single atom catalysts

Reply to the note by Li Piani et al.

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Defence technology（防务技术） 2024年第1期31卷 603-606页

作者： t.Li Piani j.Weerheijm L.j.Sluys tU Delft Stevinweg 12628 CNDelftthe Netherlands tNO PO Box 452280 AARijswijkthe Netherlands NLDA Faculty of Military Sciences1781 CADen Helderthe Netherlands

In 2017,a ballistic phenomenological model was proposed by the authors of Ref.[1] to numerically simulate the experimental depths of small caliber projectiles impacting walls made of *** opportunity for a new model in the field revealed from the observation that two older models recently used by the authors of Ref.[2] shared a linear relationship between the penetration depth P and the impacting velocity v_(O).

关键词： Penetration Adobe Modeling

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Mathematical modelling of ball and plate system with experimental and correlation function-based model validation

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Control theory and technology 2024年第2期22卷 326-341页

作者： t.R.Dil Kumar S.j.Mija Department of Electrical Engineering National Institute of Technology CalicutKozhikode673601KeralaIndia

the ball and plate system is an inherently nonlinear under actuated benchmark system used for validating the performance of various control schemes. A mathematical model depicting the dynamics close to that of the system is very much required for such a test bed. In this correspondence, the complete nonlinear model, a simplified nonlinear model, and a linearized model of the ball and plate system are developed. the system comprises a ball and plate mechanism and a rotary servo unit. the ball and plate mechanism is modelled using the Euler–Lagrange method, whereas the rotary servo subsystem is modelled from the first principles. the nonlinear model of the combined system is developed by including the dynamics of the servo motor with gear and rolling resistance between the ball and the plate. the simplified nonlinear model of the system is obtained with suitable assumptions. the model is linearized around the operating point using the jacobian. the validity of the developed models is investigated through correlation function analysis. the open-loop response of the three models, viz., nonlinear, simplified nonlinear, and linearized models, is analyzed in the MAtLAB/Simulink platform. Since the open-loop system is unstable, the experimental validation of the model is performed with a double-loop PSO (particle swarm optimization) PID control scheme.

关键词： Ball and plate system Correlation function Model validation Particle swarm optimization(PSO) PSO PID controller

Instance Segmentation of Characters Recognized in Palmyrene Aramaic Inscriptions

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Computer Modeling in Engineering & Sciences 2024年第9期140卷 2869-2889页

作者： Adéla Hamplová Alexey Lyavdansky tomášNovák Ondrej Svojše david Franc Arnošt Veselý Czech University of Life Sciences in Prague(CULS) Faculty of Economics and ManagementDepartment of Information EngineeringPrague16500Czech Republic National Research University Higher School of Economics(HSE) Faculty of HumanitiesInstitute for Oriental and Classical StudiesMoscow101000The Russian Federation

this study presents a single-class and multi-class instance segmentation approach applied to ancient Palmyrene inscriptions,employing two state-of-the-art deep learning algorithms,namely YOLOv8 and Roboflow *** goal is to contribute to the preservation and understanding of historical texts,showcasing the potential of modern deep learning methods in archaeological *** research culminates in several key findings and scientific *** comprehensively compare the performance of YOLOv8 and Roboflow 3.0 in the context of Palmyrene character segmentation—this comparative analysis mainly focuses on the strengths and weaknesses of each algorithm in this *** also created and annotated an extensive dataset of Palmyrene inscriptions,a crucial resource for further research in the *** dataset serves for training and evaluating the segmentation *** employ comparative evaluation metrics to quantitatively assess the segmentation results,ensuring the reliability and reproducibility of our findings and we present custom visualization tools for predicted segmentation *** study advances the state of the art in semi-automatic reading of Palmyrene inscriptions and establishes a benchmark for future *** availability of the Palmyrene dataset and the insights into algorithm performance contribute to the broader understanding of historical text analysis.

关键词： Optical character recognition instance segmentation Palmyrene ancient languages computer vision

Oryza CLIMtools:A genome–environment association resource reveals adaptive roles for heterotrimeric G proteins in the regulation of rice agronomic traits

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Plant Communications 2024年第4期5卷 145-165页

作者： Angel Ferrero-Serrano david Chakravorty Kobie j.Kirven Sarah M.Assmann Biology Department Pennsylvania State University208 Mueller LaboratoryUniversity ParkPA 16802USA Intercollege Graduate Degree Program in Bioinformatics and Genomics Pennsylvania State University208 Mueller LaboratoryUniversity ParkPA 16802USA

Modern crop varieties display a degree of mismatch between their current distributions and the suitability of the local climate for their *** address this issue,we present Oryza CLIMtools(https://***/CLIMtools/oryza_v1.0/),thefirst resource for pan-genome prediction of climate-associated genetic variants in a crop *** CLIMtools consists of interactive web-based databases that enable the user to(1)explore the local environments of traditional rice varieties(landraces)in South-East Asia and(2)investigate the environment by genome associations for 658 Indica and 283 japonica rice landrace accessions collected from georeferenced local environments and included in the 3K Rice Ge-nomes *** demonstrate the value of these resources by identifying an interplay betweenflowering time and temperature in the local environment that is facilitated by adaptive natural variation in OsHD2 and disrupted by a natural variant in *** quantitative trait locus analysis has suggested the impor-tance of heterotrimeric G proteins in the control of agronomic ***,we analyzed the climate associations of natural variants in the different heterotrimeric G protein *** identified a coordi-nated role of G proteins in adaptation to the prevailing potential evapotranspiration gradient and revealed their regulation of key agronomic traits,including plant height and seed and panicle *** conclude by highlighting the prospect of targeting heterotrimeric G proteins to produce climate-resilient crops.

关键词： Oryza sativa rice G by E adaptation flowering time GWAS OsHD2 OsSOC1 heterotrimeric G pro-tein OsRGA1 d1 OsGS3 OsDEP1 OsGGC2

Superplasticity of fine-grained Mg-10Li alloy prepared by severe plastic deformation and understanding its deformation mechanisms

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journal of Magnesium and Alloys 2024年第1期12卷 316-331页

作者： H.t.jeong S.W.Lee W.j.Kim Department of Materials Science and Engineering Hongik UniversityMapo-guSangsu-dong 72-1Seoul 121-791Republic of Korea

the superplastic behavior and associated deformation mechanisms of a fine-grained Mg-10.1 Li-0.8Al-0.6Zn alloy(LAZ1011)with a grain size of 3.2μm,primarily composed of the BCCβphase and a small amount of the HCPαphase,were examined in a temperature range of 473 K to 623 *** microstructural refinement of this alloy was achieved by employing high-ratio differential speed *** best superplasticity was achieved at 523 K and at strain rates of 10^(-4)-5×10^(-4)s^(-1),where tensile elongations of 550±600%were *** the heating and holding stage of the tensile samples prior to tensile loading,a significant increase in grain size was observed at temperatures above 573 ***,it was important to consider this effect when analyzing and understanding the superplastic deformation behavior and *** the investigated strain rate range,the superplastic flow at low strain rates was governed by lattice diffusion-controlled grain boundary sliding,while at high strain rates,lattice diffusion-controlled dislocation climb creep was the rate-controlling deformation *** was concluded that solute drag creep is unlikely to *** the late stages of deformation at 523 K,it was observed that grain boundary sliding led to the agglomeration of theαphase,resulting in significant strain *** mechanism maps were constructed forβ-Mg-Li alloys in the form of 2D and 3D formats as a function of strain rate,stress,temperature,and grain size,using the constitutive equations for various deformation mechanisms derived based on the data of the current tests.

关键词： Magnesium-lithium alloy Superplasticity Severe plastic deformation Grain size Grain growth

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