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Organic petrographic and mineralogical composition of the No. 6 coal seam of the Soutpansberg Coalfield, South Africa: Insights into paleovegetation and depositional environment

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International Journal of Coal Science & Technology 2024年第3期11卷 190-207页

作者： Sanki biswas Nicola J.Wagner Ofentse m.moroeng DSI-NRF CImERA/PPm Research Group Department of GeologyUniversity of JohannesburgJohannesburgSouth Africa

This study investigates the paleodepositional conditions of the No.6 Seam of the madzaringwe Formation in makhado and Voorburg south area of the Soutpansberg Coalfield(Limpopo Province,South Africa)utilizing organic petrography and inorganic geochemical *** coals are predominantly high-volatile bituminous b-A rank with high ash yields(avg.36.1 wt%),characterized by high-vitrinite(~41.5 vol%),moderate-to-high inertinite(9.8 vol%–33.7 vol%)and low liptinite(~2.3 vol%).The distribution of inertinite varies among different coal horizons(from bottom-lower to middle-upper),suggesting differential oxidation conditions and/or paleofire ***-to-inertinite(V/I)ratio,tissue preservation–gelification index(TPI–gi),and groundwater–vegetation index(GWI–VI)plots,indicate that the peat-forming forest-swamp vegetation accumulated under mesotrophic-to-rheotrophic hydrological *** presence of structured macerals(i.e.,telinite,collotelinite,fusinite,and semifusinite)suggests well-preserved plant tissues,whereas framboidal pyrite and sulphur content(0.24 wt%–2.16 wt%)point to brackish-water influence at the peat *** coals contain quartz,kaolinite,siderite,muscovite,dolomite,calcite,and pyrite minerals,most of which were likely sourced from felsic igneous *** Al/(Al+Fe+mn)and(Fe+mn)/Ti ratios for the studied samples range between 0.24–0.97 and 0.57–70.10,*** ratios,Al–Fe–mn plot,and presence of massive botryoidal-type pyrite imply some influence of meteoric waters or fluids from hydrothermal activity ***,the chemical index of alteration(CIA:98.25–99.67),chemical index of weathering(CIW:92.04–97.66),and A–CN–K ternary diagram suggest inorganic matter suffered strong chemical weathering,indicating warm paleoclimatic conditions during the coal formation.

关键词： macerals Coal facies Geochemical-indices Hydrothermal madzaringwe formation Soutpansberg Coalfield

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The Soft X-ray Imager(SXI)on the SmILE mission

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Earth and Planetary Physics 2024年第1期8卷 5-14页

作者： S.Sembay A.L.Alme D.Agnolon T.Arnold A.beardmore A.belén balado margeli C.bicknell C.bouldin G.branduardi-Raymont T.Crawford J.P.breuer T.buggey G.butcher R.Canchal J.A.Carter A.Cheney Y.Collado-Vega H.Connor T.Crawford N.Eaton C.Feldman C.Forsyth T.Frantzen G.Galgóczi J.Garcia G.Y.Genov C.Gordillo H-P.Gröbelbauer m.Guedel Y.Guo m.Hailey D.Hall R.Hampson J.Hasiba O.Hetherington A.Holland S-Y.Hsieh m.W.J.Hubbard H.Jeszenszky m.Jones T.Kennedy K.Koch-mehrin S.Kögl S.Krucker K.D.Kuntz C.Lakin G.Laky O.Lylund A.martindale J.miguel mas Hesse R.Nakamura K.Oksavik N.Østgaard H.Ottacher R.Ottensamer C.Pagani S.Parsons P.Patel J.Pearson G.Peikert F.S.Porter T.Pouliantis b.H.Qureshi W.Raab G.Randal A.m.Read N.m.m.Roque m.E.Rostad C.Runciman S.Sachdev A.Samsonov m.Soman D.Sibeck S.Smit J.Søndergaard R.Speight S.Stavland m.Steller TianRan Sun J.Thornhill W.Thomas K.Ullaland b.Walsh D.Walton C.Wang S.Yang School of Physics and Astronomy University of LeicesterLeicesterLE17RHUK Space Park Leicester University of LeicesterLeicesterLE17RHUK mullard Space Science Laboratory University College LondonDorkingRH56NTUK Centre for Electronic Imaging Open UniversityMilton KeynesMK76 AAUK birkeland Centre for Space Science Department of Physics and TechnologyUniv.of BergenN-5007 BergenNorway University of Vienna A-1010 ViennaAustria Space Research Institute Austrian Academy of SciencesA-8042 GrazAustria National Institute of Aerospace Technology MadridSpain ESTEC European Space Agency2201 AZ NoordwijkNetherlands State Key Laboratory of Space Weather National Space Science CentreBeijing 100190China University of Applied Sciences and Arts Northwestern Switzerland CH-5210 WindischSwitzerland Koegl Space GmbH CH-8157 DielsdorfSwitzerland Space Acoustics GmbH CH-8157 DielsdorfSwitzerland Zurich University of Applied Sciences 8400 WinterhurSwitzerland Genov Solutions N-5172 LoddefjordNorway STm Engineering N-5165 LaksevagNorway John Hopkins University Applied Physics Laboratory MD 20723USA NASA/Goddard Space Flight Centre MD 20771USA Center for Space Physics Boston UniversityBostonMA 02215USA Department of Theoretical Physics and Astrophysics Masaryk University60177 BrnoCzech Republic Institute of Physics E¨otvo¨s Lor´and University1053 BudapestHungary Aerospace Information Research Institute Chinese Academy of SciencesBeijing 100045China Centro de Astrobiologia(CAb) CSIC-INTAMadridSpain

The Soft X-ray Imager(SXI)is part of the scientific payload of the Solar wind magnetosphere Ionosphere Link Explorer(SmILE)*** is a joint science mission between the European Space Agency(ESA)and the Chinese Academy of Sciences(CAS)and is due for launch in *** is a compact X-ray telescope with a wide field-of-view(FOV)capable of encompassing large portions of Earth’s magnetosphere from the vantage point of the SmILE *** is sensitive to the soft X-rays produced by the Solar Wind Charge eXchange(SWCX)process produced when heavy ions of solar wind origin interact with neutral particles in Earth’s *** provides a mechanism for boundary detection within the magnetosphere,such as the position of Earth’s magnetopause,because the solar wind heavy ions have a very low density in regions of closed magnetic field *** sensitivity of the SXI is such that it can potentially track movements of the magnetopause on timescales of a few minutes and the orbit of SmILE will enable such movements to be tracked for segments lasting many *** is led by the University of Leicester in the United Kingdom(UK)with collaborating organisations on hardware,software and science support within the UK,Europe,China and the United States.

关键词： Soft X-ray Imaging micropore optics large area CCD

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Fecal microbes, short chain fatty acids, and colorectal cancer across racial/ethnic groups

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World Journal of Gastroenterology 2015年第9期21卷 2759-2769页

作者： Christina m Hester Venkatakrishna R Jala morgan gi Langille Shahid Umar K Allen Greiner bodduluri Haribabu Department of Family medicine Research Division University of Kansas Medical CenterKansas CityKS 66160United States University of Kansas Cancer Center University of Kansas medical Center Kansas CityKS 66160United States James Graham brown Cancer Center and Department of microbiology and Immunology University of LouisvilleLouisvilleKY 40202United States Department of Pharmacology Dalhousie UniversityHalifaxNS B3H 4R2Canada Department of molecular and Integrative Physiology University of Kansas Medical CenterKansas CityKS 66160United States

AIm:To investigate differences in microbes and short chain fatty acid(SCFA) levels in stool samples from Hispanic and non-Hispanic African American,American Indian,and White ***:Stool samples from twenty participants were subjected to analysis for relative levels of viable bacteria and for SCFA ***,the samples were subjected to 16 S r RNA gene pyrosequencing for identification of bacteria present in the *** used a metagenome functional prediction technique to analyze genome copy numbers and estimate the abundance of butyrate kinase in all ***:We found that African Americans had significantly lower levels of acetate,butyrate,and total SCFAs than all other racial/ethnic *** also found that participant microbial profiles differed by racial/ethnic *** Americans had significantly more Firmicutes than Whites,with enriched *** Firmicutes /bacteroidetes ratio was also significantly higher for African Americans than for Whites(P =0.049).We found Clostridium levels to be significantly and inversely related to total SCFA levels(P =0.019) and we found bacteroides to be positively associated(P =0.027) and Clostridium to be negatively associated(P =0.012) with levels of *** also identified a correlation between copy number for a butyrate kinase predicted from 16 S r RNA gene abundance and levels of butyrate in ***:The identified differences in gut flora and SCFA levels may relate to colorectal cancer mortality differentials and may be useful as targets for future clinical and behavioral interventions.

关键词： Colorectal cancer Short chain fatty acids Racial/e

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Key elements determining the intestinal region-specific environment of enteric neurons in type 1 diabetes

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World Journal of Gastroenterology 2023年第18期29卷 2704-2716页

作者： mária bagyánszki Nikolett bódi Department of Physiology Anatomy and NeuroscienceFaculty of Science and InformaticsUniversity of SzegedSzeged H-6726Hungary

Diabetes,as a metabolic disorder,is accompanied with several gastrointestinal(gi)symptoms,like abdominal pain,gastroparesis,diarrhoea or *** and complex enteric nervous system damage is confirmed in the background of these diabetic motility *** anatomical length of the gi tract,as well as genetic,developmental,structural and functional differences between its segments contribute to the distinct,intestinal region-specific effects of *** observations support and highlight the importance of a regional approach in diabetes-related enteric *** large and microvessels are essential for the blood supply of enteric *** morpho-functional linkage exists between enteric neurons and enteroglia,however,there is also a reciprocal communication between enteric neurons and immune cells on which intestinal microbial composition has crucial *** this point of view,it is more appropriate to say that enteric neurons partake in multidirectional communication and interact with these key players of the intestinal *** interplays may differ from segment to segment,thus,the microenvironment of enteric neurons could be considered strictly *** goal of this review is to summarize the main tissue components and molecular factors,such as enteric glia cells,interstitial cells of Cajal,gut vasculature,intestinal epithelium,gut microbiota,immune cells,enteroendocrine cells,prooxidants,antioxidant molecules and extracellular matrix,which create and determine a gut region-dependent neuronal environment in diabetes.

关键词： Enteric neurons Neuronal environment Gut region specificity Type 1 diabetes,Hyperglycemia microbiota-gut interactions

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Quasi-compensatory effect in emerging anode-free lithium batteries

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eScience 2021年第1期1卷 3-12页

作者： Peng Li Hun Kim Jun ming Hun-gi Jung Ilias belharouak Yang-Kook Sun Department of Energy Engineering Hanyang UniversitySeoul 04763Republic of Korea State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryCASChangchun 130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China Center for Energy Storage Research Korea Institute of Science and TechnologySeoul 02792Republic of Korea Division of Energy&Environment Technology Korea University of Science and TechnologyDaejeon 34113Republic of Korea Electrification and Energy Infrastructure Division Oak Ridge National LaboratoryOak RidgeTN 37831United States bredesen Center for Interdisciplinary Research and Graduate Education University of TennesseeKnoxvilleTN 37996United States

As electric vehicle(EV)sales grew approximately 50%year-over-year,surpassing 3.2 million units in 2020,the“roaring era”of EV is around the *** meet the increasing demand for low cost and high energy density batteries,anode-free configuration,with no heavy and voluminous host material on the current collector,has been proposed and further ***,it always suffers from several non-negligible“bottlenecks”,such as fragile solid electrolyte interface,deteriorated cycling reversibility,and uncontrolled dendrite *** by the“compensatory effect”of some disabled people with other specific functions strengthened to make up for their inconvenience,corresponding quasi-compensatory measures after anode removal,involving dimensional compensation,SEI robustness compensation,lithio-philicity compensation,and lithium source compensation,have been carried out and achieved significant battery performance *** this review,the chemistry,challenges,and rationally designed“quasi-compensatory effect”associated with anode-free lithium-ion battery are systematically discussed with several possible R&D directions that may aid,direct,or facilitate future research on lithium storage in anode-free configuration essentially emphasized.

关键词： Lithium battery Anode free Quasi-compensatory effect battery configuration

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Experimental Study of Endwall and Tip Clearance Flows in a Two- Dimensional Turbine Rotor blade Cascade - Effect of Incidence Angle

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Journal of Thermal Science 2000年第1期9卷 63-76页

作者： m. Govardhan b.H.L. Gowda R.m. Wankhade Department of mechanical Engineering Indian Institute of Technology Madras Chennai 600036 India Department of Applied Mechanics Indian Institute of Technology Madras Chennai 600 036 India(Department of Mechanical Engineering Indian Institute of T

Experimental investigations were carried out on a two-dimensional cascade fitted with a 120° deflection rotor blades to study the effect of incidence angle on the endwall flow in the presence of tip clearance. A total of five incidence angles, namely: -10°，-10° -5°, 0°, 5° ， 10° were chosen and for each incidence angle, the experiments were conducted for five tip clearance values at a constant space -chord ratio of 0.79. The results are presented in the form of contours of static pressure coefficient on the endwall and the blade tip surface. In addition, the variation of static pressure coefficient ahead of the blade leading edge and from the pressure surface to the suction surface at various axial stations, and discharge coefficient gi different axial stations are presented. The results indicate that the adverse pressure gradient upstream of the leading edge is reduced as tip clearance is increased. The contours of static pressure coefficient on the endwall indicate a deep low-pressure trough near the suction surface in comparison to the normal trough for zero clearance. Loading also increases as incidence changes from the negative to positive values. Due to area contraction caused by the tip separation vortex, the fluid moving towards the tip gap from the pressure side is accelerated. Downstream of the tip separation vortex, the endwall pressure increases due to flow mixing. The maximum value of discharge coefficient increases and the point at which maximum value occurs shifts towards leading edge when incidence is changed from -10° to 10°.

关键词： endwall blade tip surface tip clearance incidence angle tip separation vortex discharge coefficient.

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metachronous bile duct cancer nine years after resection of gallbladder cancer

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World Journal of Gastroenterology 2009年第27期15卷 3440-3444页

作者： Hye Jin Joo gi Hyun Kim Won Joong Jeon Hee bok Chae Seon mee Par Sei Jin Youn Jae Woon Choi Rohyun Sung Department of Internal medicine College of Medicine Chungbuk National UniversityGaeshindong 62 Heungdukgu Cheongju 361-711 South Korea Department of General Surgery Chungbuk National UniversityGaeshindong 62 Heungdukgu Cheongju 361-711 South Korea Department of Pathology College of Medicine Chungbuk National UniversityGaeshindong 62 Heungdukgu Cheongju 361-711 South Korea

We report a rare case of a 74-year-old man with metachronous gallbladder cancer and bile duct cancer who underwent curative resection twice, with the operations nine years apart. At the age of 65 years, the patient underwent a cholecystectomy and resection of the liver bed for gallbladder cancer. This was a welldifferentiated adenocarcinoma, with negative resection margins （T2NOm0, stage Ⅰ b）. Nine years later, during a follow-up examination, abdominal computed tomography and mRCP showed an enhanced 1.7 cm mass in the hilum that extended to the second branch of the right intrahepatic bile duct. We diagnosed this lesion as a perihilar bile duct cancer, bismuth type Ⅲ a, and performed bile duct excision, right hepatic Iobectomy and Roux-en-Y hepaticojejunostomy. The histological diagnosis was a well-differentiated adenocarcinoma with one regional lymph node metastasis （TINIm0, stage Ⅱ b）. Twelve months after the second operation, the patient is well, with no signs of recurrence. This case is compared with 11 other cases of metachronous biliary tract cancer published in the world medical literature.

关键词： biliary tree metachronous double cancer Gallbladder cancer Hilar bile duct cancer

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Three-dimensional surface model analysis in the gastrointestinal tract

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World Journal of Gastroenterology 2006年第18期12卷 2870-2875页

作者： Donghua Liao Jens b Frφk r Jian Yang Jingbo Zhao Asbjφrn m Drewes Odd H gilja Hans Gregersen Center of Excellence in Visceral biomechanics and Pain Aalborg Hospital and Institute of Health Technology Aalborg University Denmark National Center of Ultrasound in Gastroenterology Bergen University and Haukeland Hospital Bergen Norway

The biomechanical changes during functional loading and unloading of the human gastrointestinal （gi） tract are not fully understood. gi function is usually studled by introducing probes in the gi lumen. Computer modeling offers a promising alternative approach in this regard, with the additional ability to predict regional stresses and strains in inaccessible locations. The tension and stress distributions in the gi tract are related to distensibility （tension-strain relationship） and smooth muscle tone. lore knowledge on the tension and stress on the gi tract are needed to improve diagnosis of patients with gastrointestinal disorders. A modeling framework that can be used to integrate the physiological, anatomical and medical knowledge of the gi system has recently been developed. The 3-D anatomical model was constructed from digital images using ultrasonography, computer tomography （CT） or magnetic resonance imaging （IRI）. Different mathematical algorithms were developed for surface analysis based on thin-walled structure and the finite element method was applied for the mucosa-folded three layered esophageal model analysis. The tools may be useful for studying the geometry and biomechanical properties of these organs in health and disease. These studies will serve to test the structurefunction hypothesis of geometrically complex organs.

关键词： gi tract Surface Tension Stress Three-dimensional

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Heavy metals Removal from Swine Wastewater Using Constructed Wetlands with Horizontal Sub-Surface Flow

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Journal of Environmental Protection 2012年第8期3卷 871-877页

作者： Jorge A. Cortes-Esquivel Germán giácoman-Vallejos Icela D. barceló-Quintal Roger méndez-Novelo maría C. Ponce-Caballero Departamento de Ciencias básicas Universidad Autónoma Metropolitana Unidad Azcapotzalco México D.F. Facultad de Ingeniería Universidad Autónoma de Yucatán Mérida México

The removal efficiency of Cu and Zn from swine wastewater was evaluated as effected by three variables: the hydraulic retention time (HRT) (24, 48, 72 and 96 hours), two different plant species (Typha domingensis Pers. and Eleocharis cellulosa) and two different sizes of filter media (5 and 15 mm) using a horizontal sub-surface flow constructed wetland. From the results, a significant difference was observed in the removal efficiency of Cu and Zn with respect to different hydraulic retention times. The best results were obtained in the HRT of 96 hours for Zn where 96% removal of Zn with Typha domingensis Pers. specie with gravel of 15 mm (experimental unit 6) was achieved. For Cu, at 72 hours of HRT, the efficiency was nearly 100% in five of the six study units (1, 2, 3, 5 and 6). In contrast, in experimental unit 4 with gravel of 15 mm and without plants, only 86% Cu removal was achieved.

关键词： Swine Wastewater Typha domingensis Pers. Eleocharis cellulosa Heavy metals Constructed Wetlands Horizontal Sub-Surface Flow

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Involvement of serum retinoids and Leiden mutation in patients with esophageal, gastric, liver, pancreatic, and colorectal cancers in Hungary

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World Journal of Gastroenterology 2005年第48期11卷 7646-7650页

作者： Gyula mózsik Gy(o|¨)rgy Rumi András D(o|¨)m(o|¨)t(o|¨)r mária Figler beáta Gasztonyi El(?)d Papp Alajos Pár Gabriella Pár József belágyi Zoltán matus béla melegh Department of medicine Department of Human Clinical Nutrition and Dietetics Department of bioanalysis Department of biochemistry and medical Chemistry Department of medical Genetics and Child Development

AIm: To analyze the serum levels of retinoids and Leiden mutation in patients with esophageal, gastric, liver,pancreatic, and colorectal ***: The changes in serum levels of retinoids (vitamin A, α- and β-carotene, α- and β-cryptoxanthin,zeaxanthin, lutein) and Leiden mutation were measured by high liquid performance chromatography (HPLC)and polymerase chain reaction (PCR) in 107 patients (70 males/37 females) with esophageal (0/8), gastric (16/5), liver (8/7), pancreatic (6/4), and colorectal (30/21including 9 patients suffering from in situ colon cancer)cancer. Fifty-seven healthy subjects (in matched groups)for controls of serum retinoids and 600 healthy blood donors for Leiden mutation were ***: The serum levels of vitamin A and zeaxanthin were decreased significantly in all groups of patients with gastrointestinal (gi) tumors except for vitamin A in patients with pancreatic cancer. No changes were obtained in the serum levels of α- and β-carotene,α- and β-cryptoxanthin, zeaxanthin, lutein in patients with gi cancer. The prevalence of Leiden mutation significantly increased in all groups of patients with gi ***: Retinoids (as environmental factors)are decreased significantly with increased prevalence of Leiden mutation (as a genetic factor) in patients before the clinical manifestation of histologically different (planocellular and hepatocellular carcinoma, and adenocarcinoma) gi cancer.

关键词： Human gastrointestinal cancer Leiden mutation Retinoids Vitamin A Zeaxanthin

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