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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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Fast numerical generation and hybrid encryption of a computer-generated Fresnel holographic video sequence

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chinese Optics Letters 2013年第2期11卷 27-31页

作者： peter Tsang k.W.-k. cheung T.-c. Poon Department of Electronic Engineering City University of Hong KongTat Chee AvenueKowloon Bradley Department of Electrical and computer Engineering Virginia TechUSA Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences

Research demonstrates that a Fresnel hologram can be generated and simultaneously encrypted numerically based on a secret symmetric key formed by the maximal length sequence （M-sequence）. The method can be directly extended to encrypt a video holographic clip in a frame-by-frame manner. However, given the limited combination of signals in the family of M-sequence, hacking the secret key through trial and error can be time consuming but not difficult. In this letter, we propose a method that is difficult to crack with brute force for enerypting a holographic video sequence. An M-sequence is first randomly assigned to enerypt each frame of the holographic video signal. Subsequently, the index of the selected M-sequence, which is necessary to decrypt the hologram~ is encrypted with the RSA algorithm before transmitting to the receiving end. At the receiving end, the decoder is provided with a private key to recover the index for each frame, and the corresDonding M-se（mence is used to decrvDt the encoded hologram.

关键词： Access control computer generated holography cryptography Personal computing Video recording

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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 ofceeds>10 *** 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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A review of public health guidelines for postpartum physical activity and sedentary behavior from around the world

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Journal of Sport and Health Science 2024年第4期13卷 472-483,F0003页

作者： kelly R.Evenson Wendy J.Brown Alison k.Brinson Emily Budzynski-Seymour Melanie Hayman Department of Epidemiology Gillings School of Global Public HealthUniversity of North Carolina at Chapel HillChapel HillNC 27599-8050USA Faculty of Health Sciences and Medicine Bond UniversityGold CoastQLD 4226Australia School of Human Movement and Nutrition Sciences The University of QueenslandBrisbaneQLD 4072Australia Department of Anthropology University of North Carolina at Chapel HillChapel HillNC 27599-3115USA carolina Population center University of North Carolina at Chapel HillChapel HillNC 27599-8120USA Faculty of Sport Health and Social SciencesSolent UniversitySouthamptonSO140YNUK Appleton Institute School of HealthMedical and Applied SciencesCentral Queensland UniversityRockhamptonQLD 4701Australia

Background:The period following pregnancy is a critical time window when future habits with respect to physical activity(PA) and sedentary behavior(SB) are established;therefore,it warrants *** purpose of this scoping review was to summarize public health-oriented country-specific postpartum PA and SB guidelines ***:To identity guidelines published since 2010,we performed a(a) systematic search of 4 databases(cINAHL,Global Health,PubMed,and SPORTDiscus),(b) structured repeatable web-based search separately for 194 countries,and(c) separate web-based *** the most recent guideline was included for each ***:We identified 22 countries with public health-oriented postpartum guidelines for PA and 11 countries with SB *** continents with guidelines included Europe(n=12),Asia(n=5),Oceania(n=2),Africa(n=1),North America(n=1),and South America(n=1).The most common benefits recorded for PA included weight control/management(n=10),reducing the risk of postpartum depression or depressive symptoms(n=9),and improving mood/well-being(n=8).Postpartum guidelines specified exercises to engage in,including pelvic floor exercises(n=17);muscle strengthening,weight training,or resistance exercises(n=13);aerobics/general aerobic activity(n=13);walking(n=11);cycling(n=9);and swimming(n=9).Eleven guidelines remarked on the interaction between PA and breastfeeding;several guidelines stated that PA did not impact breast milk quantity(n=7),breast milk quality(n=6),or infant growth(n=3).For SB,suggestions included limiting long-term sitting and interrupting sitting with ***:country-specific postpartum guidelines for PA and SB can help promote healthy behaviors using a culturally appropriate context while providing specific guidance to public health practitioners.

关键词： Breastfeeding caesarean section Guidelines Postnatal Recommendations

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Geospatial Analysis of Urban Heat Island Effects and Tree Equity

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Open Journal of Forestry 2024年第1期14卷 1-18页

作者： Jillian Gorrell Sharon R. Jean-Philippe Paul D. Ries Jennifer k. Richards Neelam c. Poudyal Rochelle Butler School of Natural Resources University of Tennessee 203 Third Creek Building Knoxville Tennessee USA

In recent decades, Urban Heat Island Effects have become more pronounced and more widely examined. Despite great technological advances, our current societies still experience great spatial disparity in urban forest access. Urban Heat Island Effects are measurable phenomenon that are being experienced by the world’s most urbanized areas, including increased summer high temperatures and lower evapotranspiration from having impervious surfaces instead of vegetation and trees. Tree canopy cover is our natural mitigation tool that absorbs sunlight for photosynthesis, protects humans from incoming radiation, and releases cooling moisture into the air. Unfortunately, urban areas typically have low levels of vegetation. Vulnerable urban communities are lower-income areas of inner cities with less access to heat protection like air conditioners. This study uses mean evapotranspiration levels to assess the variability of urban heat island effects across the state of Tennessee. Results show that increased developed land surface cover in Tennessee creates measurable changes in atmospheric evapotranspiration. As a result, the mean evapotranspiration levels in areas with less tree vegetation are significantly lower than the surrounding forested areas. central areas of urban cities in Tennessee had lower mean evapotranspiration recordings than surrounding areas with less development. This work demonstrates the need for increased tree canopy coverage.

关键词： Spatial Analysis Land cover Urban Heat Island Effect (UHIE) Evapotranspiration Tree canopy Impervious Surface GIS Prediction Model GIS Machine Learning

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Genetic diversity of RNA viruses infecting invertebrate pests of rice

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Science china(Life Sciences) 2024年第1期67卷 175-187页

作者： Haoran Wang Shufen chao Qing Yan Shu Zhang Guoqing chen chonghui Mao Yang Hu Fengquan Yu Shuo Wang Liang Lv Baojun Yang Jiachun He Songbai Zhang Liangsheng Zhang peter Simmonds Guozhong Feng State key Laboratory of Rice Biology and Breeding China National Rice Research InstituteChinese Academy of Agricultural SciencesHangzhou 311400China State key Laboratory of Agricultural Microbiology College of Life Science and TechnologyHuazhong Agricultural UniversityWuhan 430070China Institute of Plant Protection&Soil Fertilizer Hubei Academy of Agricultural SciencesWuhan 430064China Institute of Plant Protection Guizhou Academy of Agricultural SciencesGuiyang 550000China Institute of Plant Protection Liaoning Academy of Agricultural SciencesShenyang 110161China Sanya Agricultural Technology Extension and Service centre Sanya 572000China college of Agriculture Yangtze UniversityJingzhou 434000China Fujian Provincial key Laboratory of Haixia Applied Plant Systems Biology Fujian Agriculture and Forestry UniversityFuzhou 350002China Genomics and Genetic Engineering Laboratory of Ornamental Plants College of Agriculture and BiotechnologyZhejiang UniversityHangzhou 310012China Nuffield Department of Medicine Peter Medawar Building for Pathogen ResearchUniversity of OxfordOxford OX13SYUnited Kingdom

Invertebrate species are a natural reservoir of viral genetic diversity,and invertebrate pests are widely distributed in crop ***,information on viruses infecting invertebrate pests of crops is *** this report,we describe the deep metatranscriptomic sequencing of 88 invertebrate samples covering all major invertebrate pests in rice *** identified 296 new RNA viruses and 13 known RNA *** viruses clustered within 31 families,with many highly divergent viruses constituting potentially new families and *** the identified viruses,13 RNA viruses clustered within the Fiersviridae family of bacteriophages,and 48 RNA viruses clustered within families and genera of *** detected known rice viruses in novel invertebrate hosts at high ***,some novel RNA viruses have genome structures closely matching to known plant viruses and clustered within genera of several plant virus *** potential insect pathogenic RNA viruses were detected in invertebrate *** analysis revealed that host taxonomy plays a major role and geographical location plays an important role in structuring viral ***-species transmission of RNA viruses was detected between invertebrate *** identified viral genomes showed extensive variation for invertebrate viral families or ***,the large-scale metatranscriptomic analysis greatly expands our understanding of RNA viruses in rice invertebrate species,the results provide valuable information for developing efficient strategies to manage insect pests and virus-mediated crop diseases.

关键词： invertebrate species metatranscriptome viral diversity viral transmission viral genomes

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Enhanced method for the generation of binary Fresnel holograms based on grid-cross downsampling

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chinese Optics Letters 2011年第12期9卷 15-19页

作者： W.k.cheung peter Tsang T.c.Poon 周常河 Department of Electronic Engineering City University of Hong KongTat Chee AvenueKowloon Bradley Department of Electrical and computer Engineering Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences

Past research has demonstrated that digital Fresnel holograms can be binarized in a non-iterative manner by downsampling the source image with a grid lattice prior to the hologram generation process. The reconstructed image of a hologram that is binarized with this approach is superior in quality compared with that obtained with direct thresholding, half-toning, and error diffusion. Despite the success, the downsampling mechanism results in a prominent texture of regularly spaced voids in the shaded regions. To alleviate this problem, an enhanced non-iterative method for the generation of binary Fresnel holograms is presented. Our method is based on a multi-direction line-sampling formed by a combined grid and cross lattice, which is capable of preserving a more solid texture in the shaded regions and enhancing the visual quality of the reconstructed image. computer simulations and optical reconstructions are shown to demonstrate the effectiveness of our proposed technique.

关键词： computer simulation Lithography Textures

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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

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Drought events influence nutrient canopy exchanges and green leaf partitioning during senescence in a deciduous forest

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Forest Ecosystems 2024年第1期11卷 110-119页

作者： J.Touche c.calvaruso P.De Donato M.-P.Turpault INRAE BEFF-54000NancyFrance UMR 7359 GeoRessourcesFaculte des Sciences-Campus des Aiguillettes54506Vandoeuvre Les NancyFrance EcoSustain Environmental Engineering OfficeResearch and DevelopmentKanfen57330France

The increase in the frequency and intensity of drought events expected in the coming decades in Western Europe may disturb forest biogeochemical cycles and create nutrient deficiencies in *** possible origin of nutrient deficiency is the disturbance of the partitioning of the green leaf pool during the leaf senescence period between resorption,foliar leaching and senesced ***,the effects of drought events on this partitioning and the consequences for the maintenance of tree nutrition are poorly *** experiment in a beech forest in Meuse(France)was conducted to assess the effect of drought events on nutrient canopy exchanges and on the partitioning of the green leaf pool during the leaf senescence *** aim was to identify potential nutritional consequences of droughts for *** nutrient dynamics,including resorption,chemistry of green and senesced leaves,foliar absorption and leaching in mature beech stands from 2012 to 2019 allowed us to compare the nutrient exchanges for three nondry and three dry years(i.e.,with an intense drought event during the growing season).During dry years,we observed a decrease by almost a third of the potassium(k)partitioning to resorption(*** efficiency),thus reducing the k reserve in trees for the next growing *** result suggests that with the increased drought frequency and intensity expected for the coming decades,there will be a risk of potassium deficiency in trees,as already observed in a rainfall exclusion experiment on the same study *** foliar leaching and higher parititioning to the senesced leaves for k and phosphorus(P)were also *** addition,a slight increase in nitrogen(N)resorption efficiency occurred during dry years which is more likely to improve tree *** calcium(ca)negative resorption decreased,with no apparent consequence in our study *** results show that nutrient exchanges in the canopy and the partitioning of the green leaf

关键词： Natural drought Beech forest canopy Resorption Foliar leaching Senesced leaves Nutrition

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Laparoscopic management of remnant gall bladder with stones: Lessons from a tertiary care centre's experience

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Laparoscopic, Endoscopic and Robotic Surgery 2024年第1期7卷 27-33页

作者： Gilbert Samuel Jebakumar Jeevanandham Muthiah Loganathan Jayapal R.Santhosh kumar Siddhesh Tasgaonkar k.S.Santhosh Anand J.k.A.Jameel Sudeepta kumar Swain k.J.Raghunath Prasanna kumar Reddy Tirupporur Govindaswamy Balachandar Department of Surgical Gastroenterology Apollo HospitalsChennai 600006India Department of General Surgery Apollo HospitalsChennai 600006India Department of Minimal Access Surgery Apollo HospitalsChennai 600006India

Objective:Laparoscopic cholecystectomy is currently the gold standard for treating symptomatic gallstone *** its success,approximately 10%of patients may experience persistent biliary symptoms,leading to the post-cholecystectomy syndrome.A remnant gallbladder with cystic duct or bile duct stones is one of the causes of this *** objective of this study was to shed light on the clinical manifestations,evaluation,therapeutic strategies,and outcomes associated with laparoscopic management of symptomatic remnant ***:This was a retrospective study,conducted over a five-year period(January 2017 to December 2022)at Apollo Hospitals in South *** patients who underwent laparoscopic completion cholecystectomy for a remnant gall bladder were *** following data were collected:patient demographics,symptoms,preoperative investigations,intraoperative details and post operative ***:In total,36 patients were included and *** majority of patients were male(25,69.4%),with a mean age of 50.7±12.1 *** most common presentation was pain in the upper abdomen or right upper quadrant region(24,66.7%).The laparoscopic approach was attempted in all patients,with a success rate of 94.4%.Two patients required conversion to open *** fistula to the colon was observed in one *** was observed in 7 patients(19.4%),and stone clearance was successfully achieved using endoscopic retrograde cholangiopancreatography in all patients ***:Incomplete gall bladder removal either intentionally or unintentionally leaves a remnant gall bladder that is at risk for stone formation and *** who have this clinical entity with symptoms require a redo or complete cholecystectomy,a complex procedure associated with certain *** study highlights the feasibility and safety of laparoscopic completion cholecystectomy for the management of remnant gallbladder

关键词： Remnant gall bladder Stump cholecystitis Subtotal cholecystectomy Laparoscopic completion cholecystectomy

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