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Extractable and kerogen-bound hopanoids from typical Eocene oil shales in China

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

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Dynamic Forecasting of Traffic Event Duration in Istanbul:A Classification Approach with Real-Time Data Integration

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Computers, Materials & Continua 2024年第8期80卷 2259-2281页

作者： Mesut Ulu Yusuf Sait Türkan kenan Menguc Ersin Namlı Tarık kucukdeniz Occupational Health and Safety Department Bandirma Onyedi Eylul UniversityBalikesir10200Türkiye Department of Industrial Engineering Istanbul University-CerrahpasaIstanbul34320Türkiye Department of Industrial Engineering Istanbul Technical UniversityIstanbul34467Türkiye

Today,urban traffic,growing populations,and dense transportation networks are contributing to an increase in traffic *** incidents include traffic accidents,vehicle breakdowns,fires,and traffic disputes,resulting in long waiting times,high carbon emissions,and other undesirable *** is vital to estimate incident response times quickly and accurately after traffic incidents occur for the success of incident-related planning and response *** study presents a model for forecasting the traffic incident duration of traffic events with high *** proposed model goes through a 4-stage process using various features to predict the duration of four different traffic events and presents a feature reduction approach to enable real-time data collection and *** the first stage,the dataset consisting of 24,431 data points and 75 variables is prepared by data collection,merging,missing data processing and data *** the second stage,models such as Decision Trees(DT),k-Nearest Neighbour(kNN),Random Forest(RF)and Support Vector Machines(SVM)are used and hyperparameter optimisation is performed with *** the third stage,feature selection and reduction are performed and real-time data are *** the last stage,model performance with 14 variables is evaluated with metrics such as accuracy,precision,recall,F1-score,MCC,confusion matrix and *** RF model outperforms other models with an accuracy of 98.5%.The study’s prediction results demonstrate that the proposed dynamic prediction model can achieve a high level of success.

关键词： Traffic event duration forecasting machine learning feature reduction shapley additive explanations(SHAP)

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Highlighting relationships between sand thicknesses,reservoir-seal pairs and paleobathymetry from a sequence stratigraphic perspective:An example from Tortonian Serravallian deposits,onshore Niger Delta Basin

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Energy Geoscience 2024年第1期5卷 12-23页

作者： Ifeanyichukwu S.Obi k.Mosto Onuoha Chidozie I.Princeton Dim Mobil Producing Nigeria UnlimitedLagosNigeria Department of Geology University of NigeriaNsukkaEnugu StateNigeria

The utilization of sequence stratigraphic concepts in identifying sands and their spatial continuity in distinct gross depositional settings is key,especially in frontier settings where data paucity is a common *** the Baka field,onshore Niger Delta,detailed reservoir correlation guided by sequence stratigraphic framework analysis showed the distribution of sand and shale units constituting reservoirseal pairs(RSP)correlatable across the *** the 3rd-order packages,it is observed that the lowstand systems tract(LST)and highstand systems tract(HST)contain more RSPs and thicker 4th-and 5th-order sands than the transgressive systems tract(TST).In terms of bathymetry,it is noted that irrespective of systems tracts,the RSP Index(RI)decreases from the proximal shallow/inner shelf settings to the more distal outer shelf *** all three systems tracts,intervals interpreted as lowstand prograding complexes contain the best developed sands and highest *** development within the LSTs has been controlled by a pronounced growth fault regime accompanied by high subsidence and sedimentation *** is linked to the basinward migration of the sands during prolonged sea-level fall,creating significant accommodation space for sand *** the other hand,the TSTs known to mark periods of progressive sea-level rise and landward migration of sandy facies,show thinner sands enclosed in much thicker,laterally extensive,and better-preserved deeper marine *** seismic sections indicate intense growth faulting and channelization that influenced the syn-and postdepositional development of the sand packages across the *** initial timing of deformation of subregional faults in this area coincides with periods of abrupt falls in sea *** approach could be useful for predicting sand-prone areas in frontier fields as well as possible reservoir-seal parameters required for some aspects of petroleum system analysis and quick-look volum

关键词： Reservoir-seal pairs(RSP) Systems tract Coastal swamp depobelt Bathymetry Sequence stratigraphy Niger Delta Basin

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Is primary transcatheter aortic valve implantation the new normal?

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Journal of Geriatric Cardiology 2024年第4期21卷 458-461页

作者： R.Anantharaman C.Sundar kamal kant Jena k.Arun Department of Cardiology Kauvery HospitalChennaiIndia

Degenerative calcific aortic valve stenosis(AS)is the most common valvular heart disease in elderly.^[1] It is well documented that symptomatic severe AS follows a malignant course leading to cardiogenic shock(CS).

关键词： aortic stenosis implantation

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Finite element analysis and experimental validation of polymer-metal contacts in block-on-ring configuration

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Friction 2024年第3期12卷 554-568页

作者： k.Y.Eayal AWWAD khosro FALLAHNEZHAD B.F.YOUSIF Ahmad MOSTAFA Omar ALAJARMEH A.SHALWAN Xuesen ZENG Mechanical Engineering Department Faculty of EngineeringTafila Technical UniversityTafila 66110Jordan Medical Device Research Institute College of Science and EngineeringFlinders UniversitySouth Australia 5042Australia Centre for Future Materials University of Southern QueenslandToowoomba 4350Australia Department of Manufacturing Engineering Technology Public Authority for Applied Education and TrainingKuwait 13092Kuwait

The wear profile analysis,obtained by different tribometers,is essential to characterise the wear ***,most of the available methods did not take the stress distribution over the wear profile in consideration,which causes inaccurate *** this study,the wear profile of polymer–metal contact,obtained by block-on-ring configuration under dry sliding conditions,was analysed using finite element modelling(FEM)and experimental ***’s wear equation was integrated into a developed FORTRAN-UMESHMOTION code linked with Abaqus software.A varying wear coefficient(k)values covering both running-in and steady state regions,and a range of applied loads involving both mild and severe wear regions were measured and implemented in the *** FEM was in good agreement with the *** model reproduced the stress distribution profiles under variable testing conditions,while their values were affected by the sliding direction and maximum wear depth(hmax).The largest area of the wear profile,exposed to the average contact stresses,is defined as the normal *** the critical zones were characterized by high stress concentrations reaching up to 10 times of that at the normal *** wear profile was mapped to identify the critical zone where the stress concentration is the key point in this *** surface features were examined in different regions using scanning electron microscope(SEM).Ultimately,SEM analysis showed severer damage features in the critical zone than that in the normal zone as proven by ***,the literature data presented and considered the wear features the same at any point of the wear *** this study,the normal zone was determined at a stress value of about 0.5 MPa,whereas the critical zone was at about 5.5 *** wear behaviour of these two zones showed totally different features from one another.

关键词： polymer-to-metal contact block-on-ring wear profile wear model

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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

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Influence of Component Size on the Corrosion Behavior of Ti6Al4V Alloy Fabricated by Electron Beam Powder Bed Fusion

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Acta Metallurgica Sinica(English Letters) 2024年第1期37卷 159-168页

作者： Hongyu Zheng Xin Gai Yun Bai Wentao Hou Shujun Li Yulin Hao R.D.k.Misra Rui Yang Institute of Metal Research Chinese Academy of SciencesShenyang110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang110016China Nuclear Power Institute of China Chengdu610213China Department of Metallurgical Materialsand Biomedical EngineeringThe University of Texas at El Paso500WUniversity AvenueEl PasoTX79968USA

The electrochemical behavior of Ti-6Al-4V with 1 mm and 16 mm thickness prepared by electron beam powder bed fusion(EB-PBF)was investigated in phosphate buffered *** results showed that EB-PBF Ti-6Al-4V with a larger component size was more resistant to corrosion compared to the smaller component,because of less acicularαʹphase content and moreβphase *** a non-equilibrium phase in the“high-energy state”,αʹphase has a greater susceptibility to corrode and reduces the corrosion resistance of the material,whileβphase improves corrosion resistance of titanium *** results show that the phase composition has a more significant effect on the corrosion performance than the grain size.

关键词： Electron beam powder bed fusion Ti6Al4V alloy Corrosion resistance Component size Polarisation

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Mechanisms of shoulder trauma: Current concepts

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World Journal of Orthopedics 2024年第1期15卷 11-21页

作者： konstantinos Mastrantonakis Athanasios karvountzis Christos k Yiannakopoulos Georgios kalinterakis Department of Orthopedic General Hospital of RethymnonRethymnon 73100CreteGreece 1^(st)Orthopedic Department Naval Hospital of AthensAthens 11521Greece Department of Orthopaedic Surgery National and Kapodistrian University of AthensAthens 11527Greece

Acute traumatic injuries to the glenohumeral articulation are *** types of injuries depend on age,muscle strength,bone density,and biomechanics of the traumatic *** the different mechanisms of trauma and how they affect the functional anatomical structures of the shoulder joint is crucial for the treatment of these ***,when clinicians have knowledge of these mechanisms they can accurately diagnose and treat shoulder pathology and predict distinct injury ***,we have described the fundamentals of the mechanisms of injury of the glenohumeral dislocation,dislocation with fracture of the humeral head,and the proximal humerus *** have focused on common injury mechanisms and the correlation with radiological *** and laboratory findings of distinct types of injury were also discussed.

关键词： Mechanism Hill-Sachs Shoulder dislocation Proximal humerus fracture Shoulder biomechanics

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Severe acute kidney injury due to oxalate crystal induced severe interstitial nephritis:A case report

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World Journal of Nephrology 2024年第2期13卷 24-30页

作者： Maulik k Lathiya Praveen Errabelli Sasmit Roy Neeharik Mareedu Department of Emergency Medicine Mayo Clinic Health SystemEau ClaireWI 54703United States Department of Nephrology Mayo Clinic Health SystemEau ClaireWI 54703United States Department of Nephrology Centra Lynchburg General HospitalLynchburgVA 24551United States Department of Nephrology UPMC Western MarylandCumberlandMD 21502United States

BACkGROUND Acute kidney injury(AkI)due to interstitial nephritis is a known condition primarily attributed to various *** medication-induced interstitial nephritis is common,occurrences due to non-pharmacological factors are *** report presents a case of severe AkI triggered by intratubular oxalate crystal deposition,leading to interstitial *** aim is to outline the case and its management,emphasizing the significance of recognizing uncommon causes of interstitial *** SUMMARY A 71-year-old female presented with stroke-like symptoms,including weakness,speech difficulties,and cognitive *** hypertension had been managed with hydrochlorothiazide(HCTZ)for over two *** admis-sion,severe hypokalemia and AkI were noted,prompting discontinuation of HCTZ and initiation of prednisolone for acute interstitial *** investigations,including kidney biopsy,confirmed severe acute interstitial nephritis with oxalate crystal deposits as the underlying *** treatment,initial renal function showed minimal ***,with prednisolone therapy and supportive measures,her condition gradually improved,high-lighting the importance of comprehensive *** This case underscores the importance of a thorough diagnostic approach in identifying and addressing uncommon causes of interstitial *** occurrence of interstitial nephritis due to oxalate crystal deposition,especially without typical risk factors,emphasizes the need for vigilance in clinical practice.

关键词： Acute kidney injury Interstitial nephritis Oxalate crystal Hydrochlorothiazide Hypokalemia Case report

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Estimating the subsolar magnetopause position from soft X-ray images using a low-pass image filter

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Earth and Planetary Physics 2024年第1期8卷 173-183页

作者： Hyangpyo kim Hyunju k.Connor Jaewoong Jung Brian M.Walsh David Sibeck kip D.kuntz Frederick S.Porter Catriana k.Paw U Rousseau A.Nutter Ramiz Qudsi Rumi Nakamura Michael Collier Space Research Institute Austrian Academy of Sciences8042 GrazAustria Geophysical Institute University of Alaska FairbanksFairbanksAlaska 99775USA National Aeronautics and Space Administration(NASA)Goddard Space Flight Center GreenbeltMaryland 20771USA Astronomy Department University of Maryland College ParkCollege ParkMaryland 20742USA Center for Space Physics Boston UniversityBostonMassachusetts 02215USA Department of Physics and Astronomy Johns Hopkins UniversityBaltimoreMaryland 21218USA Howard University WashingtonDC 20059USA

The Lunar Environment heliospheric X-ray Imager(LEXI)and Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)missions will image the Earth’s dayside magneto pause and cusps in soft X-rays after their respective launches in the near future,to specify glo bal magnetic reconnection modes for varying solar wind *** suppo rt the success of these scientific missions,it is critical to develop techniques that extract the magnetopause locations from the observed soft X-ray *** this research,we introduce a new geometric equation that calculates the subsolar magnetopause position(RS)from a satellite position,the look direction of the instrument,and the angle at which the X-ray emission is *** assumptions are used in this method:(1)The look direction where soft X-ray emissions are maximized lies tangent to the magnetopause,and(2)the magnetopause surface near the subsolar point is almost spherical and thus RSis nea rly equal to the radius of the magneto pause *** create synthetic soft X-ray images by using the Open Geospace General Circulation Model(OpenGGCM)global magnetohydrodynamic model,the galactic background,the instrument point spread function,and Poisson *** then apply the fast Fourier transform and Gaussian low-pass filte rs to the synthetic images to re move noise and obtain accurate look angles for the soft X-ray pea *** the filte red images,we calculate RS and its accuracy for different LEXI locations,look directions,and solar wind densities by using the OpenGGCM subsolar magnetopause location as ground *** method estimates RS with an accuracy of10 *** accuracy improves for greater solar wind densities and during southward interplanetary magnetic *** method ca ptures the magnetopause motion during southwa rd interplaneta ry magnetic field ***,the technique will enable quantitative analysis of the magnetopause motion and help reveal the daysi

关键词： soft X-ray magnetopause reconnection low-pass filter LEXI SMILE

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