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

中国中西医结合学会微循环2008学术大会

作者： Anna A．Birukova Saad Sammani Dylan Burdette jeffrey S.Murley joe G．N．Garcia david j．grdina Konstantin G．Birukov Section of Pulmonary and Critical Care Medicine Department of Medicine University of ChicagoChicagoIllinois 60637 Department of Radiation and Cellular Oncology University of ChicagoChicagoIllinois 60637

Multiple events are involved in the development of acute inflammation and injury in the lungs.A progressive rise of oxidative stress due to altered reduction-oxidation (redox) homeostasis appears to be one of the hallmarks of lung pathologies such as injury, inflammation and ischemia/***,despite the growing evidence that alteration of the redox balance in the lungs,antioxidant therapy may attenuate acute lung

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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

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

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

Late Ordovician Mass Extinction: Earth, fire and ice

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National Science Review 2024年第1期11卷 51-65页

作者： david A.T.Harper Palaeoecosystems Group Department of Earth SciencesDurham University

The Late Ordovician Mass Extinction was the earliest of the ‘big’ five extinction events and the earliest to affect the trajectory of metazoan life. Two phases have been identified near the start of the Hirnantian period and in the middle. It was a massive taxonomic extinction, a weak phylogenetic extinction and a relatively benign ecological extinction. A rapid cooling, triggering a major ice age that reduced the temperature of surface waters, prompted a drop in sea level of some 100 m and introduced toxic bottom waters onto the shelves. These symptoms of more fundamental planetary processes have been associated with a range of factors with an underlying driver identified as volcanicity. Volcanic eruptions, and other products, may have extended back in time to at least the Sandbian and early Katian, suggesting the extinctions were more protracted and influential than hitherto documented.

关键词： Ordovician LOME paleoecology palaeobiogeography biotas

One-dimensional monotone nonautonomous dynamical systems

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Science China Mathematics 2024年第2期67卷 281-314页

作者： david Cheban Faculty of Mathematics and Computer Science Laboratory of Fundamental and Applied MathematicsMoldova State UniversityChisinau 2009Moldova

This work is devoted to the study of the dynamics of one-dimensional monotone nonautonomous(cocycle) dynamical systems. A description of the structures of their invariant sets, omega limit sets,Bohr/Levitan almost periodic and almost automorphic motions, global attractors, and pinched and minimalsets is given. An application of our general results is given to scalar differential and difference equations.

关键词： one-dimensional dynamics pinched and minimal sets global attractors monotone nonautonomous cocycle almost periodic solutions scalar differential/difference equations

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Kerogen Kinetic Distributions and Simulations Provide Insights into Petroleum Transformation Fraction (TF) Profiles of Organic-Rich Shales

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journal of Earth Science 2024年第3期35卷 747-757页

作者： david A.Wood DWA Energy Limited Lincoln LN59JPUnited Kingdom

Two hundred and fifty single first-order Arrhenius reactions are simulated to generate S2 pyrograms at three heating rates 25,15,and 5°C·*** activation energy(E)and pre-exponential factor(A)of the reactions simulated follow a long-established trend of those variable values displayed by shales and *** characteristics of the transformation fraction(TF)profiles(product generation window temperatures)of the simulated single reactions are compared to the TF profiles of recorded shale pyrograms generated by multiple reactions with different E-A values lying near the defined E-A *** similarities and differences are observed between the TF profile values of the two *** similarities support the spread of E-A values involved in shale pyrogram best *** differences are most likely explained by the complexity of the multiple kerogen first-order and second-order reactions contributing to the recorded shale pyrograms versus the simplicity and crispness of the single first-order reactions *** results also justify the validity of using the previously described“variable E-A pyrogram-fitting method”of multi-heating-rate shale pyrograms enabling optimizers to choose multiple reactions from an unlimited range of E-A *** contrast,further doubt is cast on the validity of the constant-A pyrogram-fitting method used by the Easy%Ro technique,in that a distribution of reactions with a single A value is unlikely to represent the complex variety of kerogen macerals observed in shale *** profiles generated by the variable E-A pyrogram-fitting method lie close to the established E-A trend and are likely to provide more realistic TF generation window temperatures than TF profiles generated by the constant-A pyrogram-fitting method.

关键词： transformation fraction profiles simulated S2 pyrograms multiple heating rates kerogen/shale kinetics S2 pyrogram fitting techniques kerogen petroleum research.

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Integrating petrophysical data into efficient iterative cluster analysis for electrofacies identification in clastic reservoirs

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Energy Geoscience

Energy Geoscience 2024年第4期5卷 291-305页

作者： Mohammed A.Abbas Watheq j.Al-Mudhafar Aqsa Anees david A.Wood Basrah Oil Company BasrahIraq Institute of International Rivers and Eco-Security Yunnan UniversityKunming650500China Institute for Ecological Research and Pollution Control of Plateau Lakes School of Ecology and Environmental ScienceYunnan UniversityKunming650500China DWA Energy Limited LincolnUK

Efficient iterative unsupervised machine learning involving probabilistic clustering analysis with the expectation-maximization(EM)clustering algorithm is applied to categorize reservoir facies by exploiting latent and observable well-log variables from a clastic reservoir in the Majnoon oilfield,southern *** observable well-log variables consist of conventional open-hole,well-log data and the computer-processed interpretation of gamma rays,bulk density,neutron porosity,compressional sonic,deep resistivity,shale volume,total porosity,and water saturation,from three wells located in the Nahr Umr *** latent variables include shale volume and water *** EM algorithm efficiently characterizes electrofacies through iterative machine learning to identify the local maximum likelihood estimates(MLE)of the observable and latent variables in the studied *** optimized EM model developed successfully predicts the core-derived facies classification in two of the studied *** EM model clusters the data into three distinctive reservoir electrofacies(F1,F2,and F3).F1 represents a gas-bearing electrofacies with low shale volume(Vsh)and water saturation(Sw)and high porosity and permeability values identifying it as an attractive reservoir *** results of the EM model are validated using nuclear magnetic resonance(NMR)data from the third studied well for which no cores were *** NMR results confirm the effectiveness and accuracy of the EM model in predicting *** utilization of the EM algorithm for electrofacies classification/cluster analysis is ***,the clusters it establishes are less rigidly constrained than those derived from the more commonly used K-means clustering *** EM methodology developed generates dependable electrofacies estimates in the studied reservoir intervals where core samples are not ***,once calibrated with core data in some wells,the model is suitable for

关键词： Cluster analysis Electrofacies classification Expectation-maximization(EM)algorithm Clastic reservoir Maximum likelihood estimate(MLE)

Extreme Antarctic Cold of Late Winter 2023

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Advances in Atmospheric Sciences 2024年第10期41卷 1873-1880页

作者： Anastasia j.TOMANEK david E.MIKOLAjCZYK Matthew A.LAZZARA Stefano DI BATTISTA Minghu DING Mariana FONTOLAN LITELL david H.BROMWICH Taylor P.NORTON Linda M.KELLER Lee j.WELHOUSE Antarctic Meteorological Research and Data Center Space Science and Engineering CenterUniversity of Wisconsin-MadisonMadisonWisconsin 53706USA Department of Physical Sciences School of EngineeringScienceand MathematicsMadison Area Technical CollegeMadisonWisconsin 53704USA Meteogiornale via Paolo Diacono9Milano 20133Italy State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China Byrd Polar and Climate Research Center The Ohio State UniversityColumbusOhio 43210USA Department of Geography The Ohio State UniversityColumbusOhio 43210USA

Extreme cold temperatures were observed in july and August 2023,coinciding with the WINFLY(winter fly-in)period of mid to late August into September 2023,meaning aircraft operations into McMurdo Station and Phoenix Airfield were adversely ***,with temperatures below−50℃,safe flight operation was not possible because of the risk of failing hydraulics and fuel turning to gel onboard the *** cold temperatures were measured across a broad area of the Antarctic,from East Antarctica toward the Ross Ice Shelf,and stretching across West Antarctica to the Antarctic Peninsula.A review of automatic weather station measurements and staffed station observations revealed a series of sites recording new record low *** separate cold phases were identified,each a few days in duration and occurring from mid-july to the end of August 2023.A brief analysis of 500-hPa geopotential height anomalies shows how the mid-tropospheric atmospheric environment evolves in relation to these extreme cold *** monthly 500-hPa geopotential height anomalies show strong negative anomalies in *** of composite geopotential height anomalies during each of the four cold phases suggests various factors leading to cold temperatures,including both southerly off-content flow and calm atmospheric *** the atmospheric environment that leads to such extreme cold temperatures can improve prediction of such events and benefit Antarctic operations and the study of Antarctic meteorology and climatology.

关键词： Antarctica extreme cold temperature automatic weather station networks

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