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Late Maastrichtian–Paleocene chronostratigraphy from Seymour Island,James Ross Basin,Antarctic Peninsula:Eustatic controls on sedimentation

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Advances in Polar Science 2019年第3期30卷 303-327页

作者： manuel montes Elisabet BEAMUD Francisco NOZAL Sergio SANTILLANA Instituto Geológico y Minero de Espana(IGME) área de GeologíaGeomorfología y Cartografía GeológicaCalera 128760-Tres CantosMadridSpain Paleomagnetic Laboratory CCiTUB-Instituto de Ciencias de la Tierra'Jaume Almera’-CSIC Sole i Sabariss/n08028-BarcelonaSpain Instituto Antártico Argentino 25 de Mayo 1143San Martínprovincia de Buenos AiresArgentina

The Paleocene(66–56 Ma)was a critical time interval for understanding the geological history in high palaeolatitudes after the end of Cretaceous event(recovery from mass extinction,palaeoclimate,global sea level changes,among others).The sedimentary succession from Seymour Island(Antarctic Peninsula)provides key reference material from this important phase of the early Cenozoic.A detailed age model is proposed for the López de Bertodano Formation(LBF),Sobral Formation(SF)and Cross Valley–Wiman Formation(CVWF)based on a new magnetostratigraphic section which integrates previous dinoflagellate cyst biostratigraphy,Iridium anomaly(K-Pg boundary),U-Pb zircon dating(airfall tuff)and strontium isotope values from *** new composite magnetostratigraphic section,which includes the Cretaceous–Paleogene boundary,has been correlated to the GPTS from C29r up to *** top of the LBF is confirmed as latest Maastrichtian to earliest Danian(~65.4 Ma)in *** overlying SF is mostly Danian in age(~65.2–~63 Ma)and CVWF is Selandian–Thatenian(~61.3–56.9 Ma).LBF,SF and CVWF are unconformity-bounded units(alloformations)that record the geological evolution of the James Ross Basin during a period of relative decreasing tectonism but coeval with volcanic *** based internal units have been recognized,dividing each formation into allomembers(LBF:Molluscan and Cenozoic;SF:A,B and C;CVWF:Díaz,Ara?ado,Bahía Pingüino).The new age model allows correlation of base-level changes with eustatic sea-level *** bases of the SF and CVWF are correlated with the 65.3 and 61.5 Ma sea level lowstands.

关键词： Paleocene magnetostratigraphy Antarctic Peninsula James Ross Basin Seymour Island

Distribution of Nutrients and Changes in Phytoplankton Composition in a Tropical Mesotidal Estuary, Northeastern Brazil

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Open Journal of Ecology 2017年第7期7卷 460-494页

作者： Andréa Shirley Xavier da Silva Carlos Noriega Maria Luise Koening manuel Flores montes Moacyr Araujo Departamento de Oceanografia Universidade Federal de Pernambuco—UFPE Recife Brasil

Abiotic parameters and phytoplankton were collected during 2010 and 2011 with the purpose of describing the phytoplankton distribution and the environmental characteristics. The diatoms were the most representative group in terms of species richness;in terms of density, the Cyanobacteria were more representative. Diversity and equitability were generally low in the estuary due to the dominance of Microcystis aeruginosa, an opportunistic and potentially toxic species of Cyanobacteria. The estuarine region is strongly impacted by high pollutant loads, especially nitrogen and phosphate compounds. Historical series of Apparent Oxygen Utilization (AOU) showed negative trends associated with changes in the estuarine system. The main biological components changed through 1999-2011 period. The dominance of the species changed from the Bacillariophyta in previous studies to the Cyanobacteria in our study. The species Microcystis aeruginosa, through its high density, dominance and frequency of occurrence, was the key species in the area.

关键词： Coastal Environment Nutrients Biodiversity Phytoplankton Tropical Estuary

Optimal Positioning Strategy for Multi-Camera Zooming Drones

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IEEE/CAA Journal of Automatica Sinica 2024年第8期11卷 1802-1818页

作者： manuel Vargas Carlos Vivas Teodoro Alamo Department of System Engineering and Automation University of SevilleSeville 41092Spain

In the context of multiple-target tracking and surveillance applications,this paper investigates the challenge of determining the optimal positioning of a single autonomous aerial vehicle or agent equipped with multiple independently-steerable zooming cameras to effectively monitor a set of targets of *** camera is dedicated to tracking a specific target or cluster of *** key innovation of this study,in comparison to existing approaches,lies in incorporating the zooming factor for the onboard cameras into the optimization *** enhancement offers greater flexibility during mission execution by allowing the autonomous agent to adjust the focal lengths of the onboard cameras,in exchange for varying real-world distances to the corresponding targets,thereby providing additional degrees of freedom to the optimization *** proposed optimization framework aims to strike a balance among various factors,including distance to the targets,verticality of viewpoints,and the required focal length for each *** primary focus of this paper is to establish the theoretical groundwork for addressing the non-convex nature of the optimization problem arising from these *** this end,we develop an original convex approximation *** paper also includes simulations of diverse scenarios,featuring varying numbers of onboard tracking cameras and target motion profiles,to validate the effectiveness of the proposed approach.

关键词： Convex optimization projective transformation unmanned aerial vehicle visual object tracking visual surveillance.

Why is early detection of colon cancer still not possible in 2023?

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World Journal of Gastroenterology 2024年第3期30卷 211-224页

作者： Valeria Tonini manuel Zanni Department of Medical and Surgical Sciences University of BolognaBologna 40138Italy

Colorectal cancer(CRC)screening is a fundamental tool in the prevention and early detection of one of the most prevalent and lethal *** the years,screening,particularly in those settings where it is well organized,has succeeded in reducing the incidence of colon and rectal cancer and improving the prognosis related to *** considerable advancements in screening technologies and strategies,the effectiveness of CRC screening programs remains less than *** paper examined the multifaceted reasons behind the persistent lack of effect-iveness in CRC screening *** a critical analysis of current methodologies,technological limitations,patient-related factors,and systemic challenges,we elucidated the complex interplay that hampers the successful reduction of CRC morbidity and mortality *** acknowledging the ad-vancements that have improved aspects of screening,we emphasized the necessity of addressing the identified barriers *** study aimed to raise awareness of how important CRC screening is in reducing costs for this *** and early diagnosis are not only important in improving the prognosis of patients with CRC but can lead to an important reduction in the cost of treating a disease that is often diagnosed at an advanced *** more sooner can mean saving money later.

关键词： Colorectal cancer Colorectal cancer screening Colorectal screening test Colon and rectal cancer

Reproductive Biology of a Blue-tail Skinks(Plestiodon)Population from a Temperate Forest,East-central Puebla,México

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Asian Herpetological Research 2024年第3期15卷 183-193页

作者： manuel FERIA-ORTIZ Isaías hazarmabeth SALGADO-UGARTE Museo de Zoología Facultad de Estudios Superiores ZaragozaUniversidad Nacional Autónoma de MéxicoIztapalapaMéxico Laboratorio de Biometría y Biología Pesquera Facultad de Estudios Superiores ZaragozaUniversidad Nacional Autónoma de MéxicoIztapalapaMéxico

We studied the cycles of reproduction and fat bodies of a blue-tailed skink population of an undescribed species of the Plestiodon brevirostris *** maturity is attained by females and males as they both reach about 59 mm of *** started in June-July,with ovulation occurring during late-October to mid-November,and parturition in *** size varied from two to six,with a mean of 3.86±0.15 embryos in uterus,and showed a positive correlation with female body mass and *** gestation,a significant increase in the average wet mass of embryos in uterus was *** comparison,there were no notable changes in the average dry *** growth data suggest that sexual maturity,both males and females,is reached at 16-17 months of *** and epididymides exhibited maximal weight during *** regression occurred in *** apparently takes place from mid-summer to early *** stored in female fat bodies are used for vitellogenesis and for nutrition during the winter *** males,the stored lipids appear to be used in reproductive activities during the mating season.

关键词： growth litter size minimum size at maturity reproduction Scincidae viviparity

Beyond network centrality: individual-level behavioral traits for predicting information superspreaders in social media

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National Science Review 2024年第7期11卷 148-157页

作者： Fang Zhou Linyuan Lü Jianguo Liu manuel Sebastian Mariani Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of China Yangtze Delta Region Institute(Huzhou) University of Electronic Science and Technology of China School of Cyber Science and Technology University of Science and Technology of China Department of Digital Economics Shanghai University of Finance and Economics URPP Social Networks Universit?t Zürich

Understanding the heterogeneous role of individuals in large-scale information spreading is essential to manage online behavior as well as its potential offline consequences. To this end, most existing studies from diverse research domains focus on the disproportionate role played by highly connected ‘hub’ ***, we demonstrate here that information superspreaders in online social media are best understood and predicted by simultaneously considering two individual-level behavioral traits: influence and susceptibility. Specifically, we derive a nonlinear network-based algorithm to quantify individuals' influence and susceptibility from multiple spreading event data. By applying the algorithm to large-scale data from Twitter and Weibo, we demonstrate that individuals' estimated influence and susceptibility scores enable predictions of future superspreaders above and beyond network centrality, and reveal new insights into the network positions of the superspreaders.

关键词： complex networks social networks social media information spreading superspreaders

Tracking the change in Spanish greenhouse gas emissions through an LMDI decomposition model:A global and sectoral approach

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Journal of Environmental Sciences 2024年第5期139卷 114-122页

作者： Paula Fernández González María José Presno manuel Landajo Department of Applied Economics University of OviedoAuda del Cristos/n 33011 OviedoSpain

The reduction of GHG emissions to reverse the greenhouse effect is one of the main challenges in this *** this paper we pursue two ***,we analyze the evolution of GHG emissions in Spain in 2008–2018,at both the global and sectoral levels,with the variation in emissions decomposed into a set of determining ***,we propose several actions specifically oriented to more tightly controlling the level of *** results showed a remarkable reduction(18.44%)in GHG emissions,mainly due to the intensity effect,but also to the production-per-capita *** detected somewhat different patterns among the various sectors *** the intensity effect was the most influential one in the agricultural,transport,and others sectors,the production-per-capita effect was predominant in the case of *** carbonization effect was revealed as crucial in the commerce *** above findings highlight the importance of the energy efficiency measures taken in recent years in the Spanish economy,also pointing to the need to deepen those strategies and to propose new measures that entail greater efficiency in *** efforts in areas like innovation,R&D,diffusion of more eco-friendly technologies,and a greater use of greener energies all prove to be essential reduction actions to fight the greenhouse effect.

关键词： LMDI Decomposition Spain GHG emissions

Dynamics of Primary Productivity and Oceanographic Parameters under Influence of the Amazon River Plume

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Open Journal of Ecology 2018年第11期8卷 590-606页

作者： Amanda Otsuka Fernando Feitosa Moacyr Araújo Dóris Veleda Maria da Gloria Silva Cunha Nathalie Lefévre Felipe Gaspar manuel Flores montes Gislayne Borges Carlos Noriega Department of Oceanography Federal University of Pernambuco Recife Brazil IRD-LOCEAN Sorbonne Universités (Université Pierre et Marie Curie-CNRS-MNHN) Paris France

The watershed of the Amazon River discharges about 120,000 m3·s-1?of freshwater into the adjacent platform and oceanic region. The aim of this work was to analyze the distribution of oceanographic parameters, chlorophyll a and primary productivity under the influence of the Amazon River plume, during the period of greatest extension of the Amazon plume. Collections were carried out in September 14 in 16 stations including continental platform and oceanic region. It was possible to observe superficial currents along the coast in the northwest direction, but with less intensity and currents with greater speeds towards the east due to the North Brazil Current retroflexion at this time of the year, transporting the plume to the central Atlantic Ocean. The spatial influence of the plume was observed in the salinity, which ranged from 28 to 36.75, although the high precipitation in the region may also have contributed as a source of freshwater. However, the sampled region showed strong negative linear correlation of silicate, chlorophyll a and primary productivity with salinity. The primary productivity values ranged from 0.04 to 18.81 mg C m-3?day-1, whereas chlorophyll a concentrations ranged from 0.15 mg·m-3?to 1.83 mg·m-3, decreasing their values as they move away from the coast. The Amazon River plume can reach and influence the oceanographic and biological parameters in a large area of this oligotrophic region. However, the results also suggest that the export of material from the adjacent coastal region is another determinant of the region’s productivity.

关键词： Amazon River Plume Continental Shelf Oceanic Region Environmental Variables Phytoplankton Biomass Primary Productivity

Scanning transmission electron microscopy and atom probe tomography analysis of non-stoichiometry long-period-stacking-ordered structures in Mg-Ni-Y/Sm alloys

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Journal of Magnesium and Alloys 2024年第3期12卷 954-965页

作者： Yimeng Chen manuel Legrée Jean-Louis Bobet Alexander Kvit CAMECA Instruments Inc MadisonWI 53711USA ICMCB Universitéde BordeauxPessacCEDEX 33608France NIAC&Materials Science Department University of WisconsinMadisonWI 53706USA

The long-period-stacking-ordered(LPSO)structure affects the mechanical,corrosion and hydrolysis properties of Mg *** current work employs high angle annular dark field-scanning transmission electron microscopy(HAADF-STEM)and atom probe tomography(APT)to investigate the structural and local chemical information of LPSO phases formed in Mg-Ni-Y/Sm ternary alloys after extended isothermal *** on the alloying elements and their concentrations,Mg-Ni-Y/Sm develops a two-phase LPSO+α-Mg structure in which the LPSO phase contains defects,hybrid LPSO structure,and Mg ***-STEM and APT indicate non-stoichiometric LPSO with incomplete Ni_(6)(Y/Sm)_(8) *** addition,the APT quantitatively determines the local composition of LPSO and confirms the presence of Ni within the Mg bonding *** results provide insight into a better understanding of the structure and hydrolysis properties of LPSO-Mg alloys.

关键词： Magnesium alloys Long-range ordering Atom probe tomography(APT) STEM HAADF Hydrolysis properties.