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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

Enhancing prognostic accuracy in predicting rectal neuroendocrine neoplasms

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World Journal of Gastroenterology 2024年第37期30卷 4087-4089页

作者： Renin Peter aa Raj Abdulqadir J nashwan Department of Medicine Aston Medical SchoolBirmingham B47ETUnited Kingdom Department of nursing&Midwifery Research Hamad Medical CorporationDoha 3050Qatar

The recently published retrospective study introduces the GATIS score,a new predictive model for rectal neuroendocrine *** analyzing data from a large Chinese multicenter cohort,the study shows that the GATIS score,incor-porating tumor grade,T stage,tumor size,age,and prognostic nutritional index,demonstrates superior predictive power for overall survival and progression-free survival compared to traditional World Health Organization grade and tumor,nodes and metastases staging *** editorial aims to discuss the impor-tance of the GATIS score,its potential impact on clinical practice,and the strengths and limitations of the ***,it explores the significance,methodology,and clinical implications of these findings.

关键词： Rectal neuroendocrine neoplasm nomogram Random forest Prognosis Overall survival Progression-free survival

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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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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Stress tensors and quantification of fracture patterns to analyze connectivity and potential fluid flow in a mesa landform of the northern Andes

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Journal of Mountain Science 2024年第1期21卷 271-291页

作者： GARCÍA-ARIAS Sergio VELAnDIA Francisco alvarez Angélica SAnABRIA-GÓMEZ JoséD TARAZOnA Yessenia VARGAS María Camila Escuela de Geología Universidad Industrial de SantanderCra.27 Calle 9BucaramangaColombia Escuela de Física Universidad Industrial de SantanderCra.27 Calle 9BucaramangaColombia

This work applies stress tensors inversions and quantification of fracture patterns along the Mesa de Los Santos, in the Eastern Cordillera of Colombia, to better understand the potential fluid flow. It thus contributes to the conceptual hydrogeological model. The area was subdivided into three blocks, separated by the nW Potreros and the Los Santos faults, having minor inner faults of different orientations. This separation facilitates the analysis of the fractures measured in the field, which in general show high dip angles and a conjugate geometry in the northern block, tension fractures(Mode I) in the central block, and a random distribution in the southwestern block. WinTensor treatment of slickensides yielded a maximum horizontal stress(SHmax) of 111o, which coincides with the WnW-ESE tensor observed from the conjugate and tension joints. We then used Frac Pa Q to generate interpolation maps of fracture intensity and density. The maps show the highest values in the central block and the lowest in the northern block,where the precipitation is higher, causing intensive rock weathering and homogenization of the fracture planes. Although the highest values of connectivity by line are found to the south of the mesa, we suggest the possibility of greater flow from the recharge zone(nE) along bedding planes and open nW-SE fractures.

关键词： Mesa de Los Santos Colombia Win-Tensor FracPaQ Strike-slip faults Fractured aquifers

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The neglect of nonnative orthopterans as potential invaders:A call for awareness

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Insect Science 2024年第4期31卷 994-1000页

作者： Anna K.Kulessa Paride Balzani Ismael Soto Antonín Kouba david Renault Ali Serhan Tarkan Phillip J.Haubrock Ruhr University Bochum Faculty of Biology and BiotechnologyBochumGermany Faculty of Biology University of Duisburg-EssenUniversitätsstraße 5EssenGermany Faculty of Fisheries and Protection of Waters South Bohemian Research Center of Aquaculture and Biodiversity of HydrocenosesUniversity of South Bohemia in CˇeskéBudeˇjoviceVodnˇanyCzech Republic University of Rennes CNRSECOBIO(EcosystèmesBiodiversitéEvolution)UMRRennesFrance Faculty of Fisheries Department of Basic SciencesMu˘gla SıtkıKoçman UniversityMu˘glaTurkey Department of Life and Environmental Sciences Bournemouth UniversityPooleDorsetUK Faculty of Biology and Environmental Protection Department of Ecology and Vertebrate ZoologyUniversity ofŁodzŁodzPoland Department of River Ecology and Conservation Senckenberg Research Institute and Natural History Museum FrankfurtGelnhausenGermany Center for Applied Mathematics and Bioinformatics Gulf University for Science and TechnologyMubarak Al-AbdullahKuwait

Despite the potential ecological and economic impacts of invasive species,there is a dearth of data on the presence,impacts,and management implications of potentially invasive Orthoptera *** lack of research and inconsistent data,including risk screenings and impact assessments,is especially evident in ***,assessing the status,distribution,and potential threats of nonnative Orthoptera in Europe remains challenging,impeding the development of effective management *** address this gap,we call for increased efforts to collect and curate data on non-native and possibly invasive Orthoptera in *** efforts will improve our understanding of this order’s invasion dynamics,facilitate the identification of priority areas for conservation,and support the development of effective management policies and preventive measures.

关键词： costs cricket damages grasshopper impact research

Optimizing nutrition in hepatic cirrhosis:A comprehensive assessment and care approach

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World Journal of Gastroenterology 2024年第10期30卷 1313-1328页

作者： Osvely Mendez-Guerrero Anaisa Carranza-Carrasco Luis Alberto Chi-Cervera Aldo Torre nalu navarro-alvarez Department of Gastroenterology Instituto Nacional de Ciencias Médicas y Nutrición Salvador ZubiránMexico City 14080Mexico Clínica de Especialidades Gastrointestinales y Hepáticas Hospital Star MedicaMerida 97133YucatanMexico Molecular Biology Universidad Panamericana School of MedicineCampus MéxicoMexico City 03920Mexico Department of Surgery University of Colorado Anschutz Medical CampusDenverCO 80045United States

Cirrhosis is considered a growing cause of morbidity and mortality,which represents a significant public health ***,there is no effective treatment to reverse *** primarily centers on addressing the underlying liver condition,monitoring,and managing portal hypertension-related complications,and evaluating the potential for liver transplantation in cases of decompensated cirrhosis,marked by rapid progression and the emer-gence of complications like variceal bleeding,hepatic encephalopathy,ascites,malnutrition,and ***,a prevalent complication across all disease stages,is often underdiagnosed in cirrhosis due to the complexities of nutritional assessment in patients with fluid retention and/or obesity,despite its crucial impact on *** emphasis has been placed on the collaboration of nutritionists within hepatology and Liver transplant teams to deliver compre-hensive care,a practice that has shown to improve *** review covers appropriate screening and assessment methods for evaluating the nutritional status of this population,diagnostic approaches for malnutrition,and context-specific nutrition *** also discusses evidence-based recommendations for supplementation and physical exercise,both essential elements of the standard care provided to cirrhotic patients.

关键词： Cirrhosis nutritional diagnosis Treatment Diet Guidelines

Use of oilseed crops biomass for heavy metal treatment in water

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Oil Crop Science 2024年第3期9卷 177-186页

作者： Carlos Pena-Guzman Angela Otalvaro-alvarez Tatiana Jimenez-Ariza Environmental and Sanitation Engineering Program Faculty of EngineeringUniversidad de La SalleBogota111711Colombia Chemical Enineering Program Facultuy of EngineeringUniversidad de La SalleBogota111711Colombia Food Engineering Program Faculty of EngineeringUniversidad de La SalleBogota111711Colombia

The treatment of heavy metals in water is of high importance worldwide,and different treatment types have been *** use of plant material is becoming more and more important,and oilseed crops biomass have been investigated in terms of phytoremediation and biosorption *** article is a review of the literature reporting the applications in 10 different plants and evaluating the removal efficiencies for 12 metals,including the findings of 81 *** olifera and Helianthus annuus are the most studied plants,whereas Cu(21.9%),Cd(18.5%),and Pb(19.9%)are the most studied *** a result,it was found that more than 90%of Pb,Cu,Cd,Fe,Zn,ni,Cr,Sr and Mn showed removals in their *** the same time,the variables most related to the efficiency of metal removal are pH,temperature,and contact *** article includes a review of the biosorption isotherms used in the different studies.

关键词： Oilseed crops Phytoremediation Biosorption Heavy metals