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extractable and kerogen-bound hopanoids from typical eocene oil shales in China

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energy geoscience 2024年第2期5卷 171-179页

作者： Changbo Zhai Zhirong Zhang John k.Volkman Hong Lu Yan'e Chen SINOPeC key Laboratory of Petroleum Accumulation Mechanisms Wuxi Institute of Petroleum GeologySINOPEC2060 Lihu RoadWuxiJiangsu213126China SINOPeC Petroleum exploration and Production Research Institute 31 Xueyuan RoadBeijing100083China State key Laboratory of Organic geochemistry Guangzhou Institute of GeochemistryChinese Academy of ScienceGuangzhou510640GuangdongChina

This study conducted a comparative analysis of extractable hopanoid hydrocarbons and those released via stepwise pyrolysis of typical eocene immature oil shales in China,namely the Huadian,Maoming,and Fushun *** the Huadian and Maoming shales exhibit immature indicators in extractable and kerogen-bound hopanoids(notably,high abundance of C_(29)to C_(32)17β,21β-hopanes and unsaturated hopenes).In contrast,the Fushun oil shale's hopanoids from extracts and pyrolyzates suggest a higher maturity *** absence of neohopenes in the pyrolyzates of the shales underpins that the kerogenbound hopanoid skeletons resist ***,the Huadian oil shale's asymmetric distribution of C_(29)and C_(30)hopenes and neohopenes hints at the presence of an additional *** unsaturated hopenes,such as hop-20(21)-enes,identified in pyrolyzates of the three kerogens at various pyrolysis temperatures,reveal the occurrence of double bonds in kerogen-bound hopanoid skeletons without methyl *** absence of hop-20-(21)-ene in extracts suggests that it might act as an intermediate of these novel hopenes during the epimerization of hopanoid skeletons within *** extractable and pyrolytic hopanoids'stereochemical alignment indicates that epimerization may occur in both ring systems and alkyl side chains of kerogen-bound hopanoid *** stepwise pyrolysis proves to be a quick screening method for geological hopanoids without causing any significant alteration to the original skeletons even when cracking multiple covalent bonds is necessary.

关键词： Hopanoid Hopane Hopene Neohopene Stepwise pyrolysis kerogen eocene oil shale

early-onset gastrointestinal cancer:An epidemiological reality with great significance and implications

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World Journal of gastrointestinal Oncology 2024年第3期16卷 583-597页

作者： John k Triantafillidis konstantinos georgiou Manousos M konstadoulakis Apostolos e Papalois Department of IBD and gI endoscopy Metropolitan General HospitalHolargos 15562AthensGreece.Hellenic Society for Gastrointestinal Oncology354 Iera OdosChaidari 12461AtticaGreece 2nd Department of Surgery University of Athens School of MedicineAretaieion HospitalAthens 11528Greece

During the last few years,epidemiological data from many countries suggest that the incidence and prevalence of many cancers of the digestive system are shifting from the older to the younger ages,the so-called“early-onset cancer”.This is particularly evident in colorectal cancer and secondarily in other malignant digestive neoplasms,mainly stomach and in a lesser degree pancreas,and biliary *** should be emphasized that data concerning digestive neoplasms,except for those referring to the colon and stomach,could be characterized as rather *** exact magnitude of the shift in younger ages is expected to become clearer shortly,as long as relevant epidemiological data from many parts of the world would be *** most important question concerns the etiology of this phenomenon,since its magnitude cannot be explained solely by the better diagnostic methodology and the preventive programs applied in many *** existing data support the assumption that a number of environ-mental factors may play a primary role in influencing carcinogenesis,sometimes from *** that have appeared in the last decades related mainly to eating habits,consistency of gut microbiome and an increase of obese people interacting with genetic factors,ultimately favor the process of *** these factors however,are not entirely sufficient to explain the age-related changes in the frequency of digestive *** of the individual effect of each of the already known factors or factors likely to be involved in the etiology of this phenomenon and studies using state-of-the-art technologies to accurately determine the degree of the population exposure to these factors are *** this article,we attempt to describe the epidemiological data supporting the age-shifting of digestive malignancies and their possible ***,we propose some measures regarding the attitude of the scientific community to this alarming phenomenon.

关键词： gastrointestinal cancer endoscopy epidemiology early-onset environment

The magnetosheath at high spectral resolution

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earth and Planetary Physics 2024年第1期8卷 234-246页

作者： k.D.küntz D.koutroumpa W.R.Dunn A.Foster F.S.Porter D.g.Sibeck B.Walsh The Henry A.Rowland Department of Physics and Astronomy Johns Hopkins University3701 San Martin DriveBaltimoreMD21218USA NASA goddard Space Flight Center 8800 Greenbelt RoadGreenbeltMD 20771USA LATMOS-OVSQ CNRSUVSQ Paris-SaclaySorbonne Université11 Boulevard d’Alembert78280GuyancourtFrance Department of Physics and Astronomy University College LondonLondonUK The Centre for Planetary Science at UCL/Birkbeck Gower StreetLondon WC1E 6BTUK Center for Astrophysics Harvard University&Smithsonian Institution60 Garden StreetCambridgeMA 02138USA Center for Space Physics Boston University110 Cummington MallBostonMAUSA

While we eagerly anticipate SMILe’s(Solar wind Magnetosphere Ionosphere Link explorer)unprecedented X-ray observations of the earth’s magnetosheath and the initiation of a new era of magnetospheric research,it seems appropriate to look ahead to the abilities of the next generation of astrophysics *** these,the Line emission Mapper(LeM),a large aperture micro-calorimeter based mission,is currently planned to be able to observe the magnetosheath at high spectral resolution(~2 eV).With a field of view of~30′,LeM will allow higher spatial resolution and higher cadence measurement of the motion of a very small portion of the magnetopause over relatively short periods of time(multiple hours),complementing SMILe’s global ***’s strength is its spectral *** will be able to measure the abundance of a broad range of elements and ionization states,many of which are inaccessible to current in situ instruments,and will be able to separate the emission from the magnetosheath from the emission from the cosmic X-ray background using the difference in their relative velocities.

关键词： magnetosheath charge exchange solar wind abundances

Numerical Analysis of the Magnetic Dipole effect on a Radiative Ferromagnetic Liquid Flowing over a Porous Stretched Sheet

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Fluid Dynamics & Materials Processing 2024年第2期20卷 293-310页

作者： g.Dharmaiah F.Mebarek-Oudina k.S.Balamurugan N.Vedavathi Department of Mathematics Narasaraopeta Engineering CollegeNarasaraopetIndia Department of Physics Faculty of SciencesUniversity of 20 Août 1955-SkikdaSkikdaAlgeria Department of Mathematics RVR&JC College of EngineeringGunturIndia Department of Mathematics Koneru Lakshmaiah Education FoundationVaddeswaramIndia

The effects of a magnetic dipole on a nonlinear thermally radiative ferromagnetic liquidﬂowing over a stretched surface in the presence of Brownian motion and thermophoresis are *** means of a similarity transformation,ordinary differential equations are derived and solved afterwards using a numerical(the BVP4C)*** impact of various parameters,namely the velocity,temperature,concentration,is presented *** is shown that the nanoparticles properties,in conjunction with the magnetic dipole effect,can increase the thermal conductivity of the engineered nanoﬂuid and,consequently,the heat *** with earlier studies indicates high accuracy and effectiveness of the numerical *** increase in the Brow-nian motion parameter and thermophoresis parameter enhances the concentration and the related boundary *** skin-friction rises when the viscosity parameter is increased.A larger value of the ferromagnetic para-meter results in a higher skin-friction and,vice versa,in a smaller Nusselt number.

关键词： Brownian motion thermo-phoresis radiation magnetic dipole BVP4C non-linear

Aqueous-phase reforming of hydroxyacetone solution to bio-based H_(2)over supported Pt catalysts

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green energy & environment 2024年第4期9卷 777-788页

作者： A.k.k.Vikla k.koichumanova Songbo He k.Seshan Joint International Research Laboratory of Circular Carbon Nanjing Tech UniversityNanjing211816China Faculty of Science and Technology University of Twente7500 AE EnschedeThe Netherlands CoRe Pro 9723 BL GroningenThe Netherlands

Aqueous-phase reforming(APR)is an attractive process to produce bio-based hydrogen from waste biomass streams,during which the catalyst stability is often challenged due to the harsh reaction *** this work,three Pt-based catalysts supported on C,AlO(OH),and ZrO_(2)were investigated for the APR of hydroxyacetone solution in afixed bed reactor at 225℃and 35 *** them,the Pt/C catalyst showed the highest turnover frequency for H_(2)production(TOF of 8.9 molH_(2)molPt^(-1)min^(-1))and the longest catalyst *** the AlO(OH)and ZrO_(2)supported Pt catalysts,the side reactions consuming H_(2),formation of coke,and Pt sintering result in a low H_(2)production and the fast catalyst *** proposed reaction pathways suggest that a promising APR catalyst should reform all oxygenates in the aqueous phase,minimize the hydrogenation of the oxygenates,maximize the WgS reaction,and inhibit the condensation and coking reactions for maximizing the hydrogen yield and a stable catalytic performance.

关键词： APR Hydroxyacetone TOF Bio-based H_(2) Support effect

ground-based and additional science support for SMILe

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earth and Planetary Physics 2024年第1期8卷 275-298页

作者： J.A.Carter M.Dunlop C.Forsyth k.Oksavik e.Donovon A.kavanagh S.e.Milan T.Sergienko R.C.Fear D.g.Sibeck M.Connors T.Yeoman X.Tan M.g.g.T.Taylor k.McWilliams J.gjerloev R.Barnes D.D.Billet g.Chisham A.Dimmock M.P.Freeman D.-S.Han M.D.Hartinger S.-Y.W.Hsieh Z.-J.Hu M.k.James L.Juusola k.kauris.ie.e.a.kronbe.g M.Lester J.Manuel J.Matzka I.McCrea Y.Miyoshi J.Rae L.Ren F.Sigernes e.Spanswick k.Sterne A.Steuwer T.Sun M.-T.Walach B.Walsh C.Wang J.Weygand J.Wild J.Yan J.Zhang Q.-H.Zhang Planetary Sciences group School of Physics and AstronomyUniversity of LeicesterUniversity RoadLeicesterLE17RHUK Rutherford Appleton Laboratory Space Science Technology Facilities CouncilOxfordshireUK School of Space and environment Beihang UniversityBeijing 100191China key Laboratory of Space environment Monitoring and Information Processing Ministry of Industry and Information TechnologyBeijing 100017China Department of Space and Climate Physics UCLMullard Space Science LaboratoryHolmbury St.MaryDorkingSurreyRH56NTUK Birkeland Centre for Space Science Department of Physics and Technology.University of BergenBergenNorway Department of Physics and Astronomy University of Calgary2500 University DriveCalgaryAlbertaCanada T2N 1N4 British Antarctic Survey CambridgeUK Swedish Institute of Space Physics KirunaSweden West Highfield Campus University of SouthamptonUniversity RoadSO171BJUK goddard Space Flight Center NASAGreenbeltMarylandUSA Athabasca University AthabascaCanada eSTeC European Space AgencyNetherlands University of Saskatchewan SaskatoonCanada The Johns Hopkins University Applied Physics Laboratory LaurelMarylandUSA Swedish Institude of Space Physics UppsalaSE 75121Sweden Tongji University Shanghai 200092China Center for Space Plasma Physics Space Science Institute4765 Walnut Street Suite BBoulderColorado80301USA Polar Research Institute of China Shanghai 200136China Finnish Meteorological Institute(FMI) Finland Department of earth and environmental Sciences(geophysics) Ludwig Maximilian University of Munich(LMU)MunichTheresienstr.41MunichD-80333Germany Canadian Space Agency MontrealCanada gFZ german Research Centre for geosciences PotsdamGermany Nagoya University Institute for Space Earth Environment ResearchCenter for Integrated Data ScienceNagoyaAichiJP 464-8601 Northumbria University Newcastle upon TyneTyne and WearUK NE18ST National Space Science Center Chinese Academy SciencesBeijing 100190China Arctic geophysics University Centre in Svalbard

The joint european Space Agency and Chinese Academy of Sciences Solar wind Magnetosphere Ionosphere Link explorer(SMILe)mission will explore global dynamics of the magnetosphere under varying solar wind and interplanetary magnetic field conditions,and simultaneously monitor the auroral response of the Northern Hemisphere *** these large-scale responses with medium and fine-scale measurements at a variety of cadences by additional ground-based and space-based instruments will enable a much greater scientific impact beyond the original goals of the SMILe ***,we describe current community efforts to prepare for SMILe,and the benefits and context various experiments that have explicitly expressed support for SMILe can offer.A dedicated group of international scientists representing many different experiment types and geographical locations,the ground-based and Additional Science Working group,is facilitating these *** include constructing an online SMILe Data Fusion Facility,the discussion of particular or special modes for experiments such as coherent and incoherent scatter radar,and the consideration of particular observing strategies and spacecraft *** anticipate growing interest and community engagement with the SMILe mission,and we welcome novel ideas and insights from the solar-terrestrial community.

关键词： magnetosphere ionosphere magnetosphere-ionosphere coupling ground-based experimentation SMILe conjunctions missions

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

geochemistry and depositional environment of fuchsite quartzites from Sargur group,western Dharwar Craton,India

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Acta geochimica 2024年第3期43卷 555-570页

作者： C.S.Sindhuja g.Harshitha C.Manikyamba k.S.V.Subramanyam CSIR(Council of Scientific and Industrial Research)-National geophysical Research Institute(NgRI) Uppal RoadHyderabad 500007India

Meso-Neoarchean fuchsite quartzites are present in different stratigraphic positions of Dharwar Craton including the oldest(~3.3 ga)Sargur group of western Dharwar *** present study deals with the petro-graphic and geochemical characteristics of the fuchsite quartzites from the ghattihosahalli belt to evaluate their genesis,depositional setting and the enigma involved in the ancient sedimentation *** major mineral assemblages include quartz,fuchsite,and feldspars along with accessory kyanite and *** geochemical com-positions are characterized by high SiO_(2),Al_(2)O_(3),low MgO,CaO,strongly enriched Cr(1326–6899 ppm),Ba(1165–3653 ppm),Sr(46–210 ppm),V(107–868 ppm)and Zn(11–158 ppm)contents compared to the upper continental crust(UCC).The UCC normalized rare earth element(Ree)patterns are characterized by depleted light Ree[(La/Sm)UCC=0.33–0.95]compared to heavy Ree[(gd/Yb)_(UCC)=0.42–1.65]with conspicuous positive eu-anomalies(eu/eu^(*)=1.35–18.27)characteristic of hydrothermal solutions evidenced through the interlayered *** overall major and trace element systematics reflect a combined mafic-felsic provenance and suggest their deposition at a passive continental margin *** comprehensivefield,petrographic,and geo-chemical studies indicate that these quartzites are infiltrated by Cr-richfluids released during high-grade metamorphism of associated ultramafic *** Sargur and the subse-quent Dharwar orogeny amalgamated diverse lithounits from different tectonic settings,possibly leading to the release of Cr-richfluids and the formation of fuchsite quartzite during or after the *** sug-gest a pre-existing stable crust prior to the Sargur group and the link between orogenic events and various mineral deposits in the Dharwar Craton.

关键词： Dharwar Craton ghattihosahalli Fuchsite quartzite Provenance Depositional setting

Cytomegalovirus Transverse Myelitis Secondary to Influenza Infection and early Recovery:A Case Report

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Infectious Diseases & Immunity 2024年第1期4卷 41-42页

作者： Jill S.Bhavsar Lekhini k.Fultariya Poojan J.Prajapati Archi k.Dhamelia Jaime e.Campos Department of Infectious Disease Hialeah HospitalMiamiFL(affiliated with HerbertWertheim College of MedicineFlorida International University)33013USA

Immunosuppression can lead to opportunistic infections in a *** evidence of viral infections causing immunosuppression in a host for a transient period is gaining *** order to prolong their stay in the human body,viruses affect the human immune systemin various *** viral infections such as influenza can lead to transient lymphocytopenia,which lays the groundwork for more dangerous opportunistic ***(CMV)infection is a rare cause of inflammatory *** present the case of a patient with an influenza infection who progressed to severe acute respiratory distress syndrome,methicillin-resistant Staphylococcus aureus necrotizing pneumonia,and idiopathic lymphocytopenia with a CD4 count of 61 perμL on *** 2 weeks,the patient developed complete flaccid paralysis with sensory and autonomic *** his polymerase chain reaction results of cerebrospinal fluid and blood test were positive for CMV infection,he was treated with high doses of steroids and ganciclovir *** to early diagnosis and intervention,the patient was able to recover in 2 months with only minimal residual ***,this case stresses on the importance of looking out for opportunistic infections in patients affected by severe viral infections for their early recovery.

关键词： Influenza,Human Lymphocytopenia Transverse myelitis Case report