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contributions to the knowledge of Antarctodon sobrali(Mammalia:Astrapotheria)from the Eocene of Antarctica

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Advances in Polar Science 2024年第1期35卷 48-62页

作者： Javier n.GELFO consejo nacional de Investigaciones científicasy Técnicas(cOnIcET) Buenos Aires C1425FQBArgentina División Paleontología Vertebrados Museo de La PlataFacultad de Ciencias Naturales y Museo de La PlataUniversidad Nacional de La PlataLa Plata B1900FWAArgentina

The Astrapotheria constitutes one of the five orders of extinct South American native ungulates,with a fossil record that also extends to the Eocene of the Antarctic *** contrast to the abundant specimens known for litoptern Sparnotheriodontidae and metatherians,astrapotheres are represented by scant remains assigned to the endemic Antarctodon sobrali and indeterminate astrapotheres,restricted to levels 35c_(u0)and 35n of the cucullaea I Allomember of the La Meseta *** discovery of alower molar assignable to this species in the Eocene levels of Seymour(Marambio)Island,enables a revision of the diagnosis and the homologies of the dental characters used to describe this taxon.A reanalysis of its phylogenetic relationships reveals the nearly simultaneous presence of basal astrapotheres in the early Eocene of Itaboraí(Brazil),Patagonia,and West *** taxa are characterized by lacking dental specializations usually associated with more abrasive diets like terminal forms of Uruguaytheriinae and *** appears to have thrived on the Antarctic continent during the Early Eocene climatic Optimum within the paleoclimatic context of a hot-house *** present conditions in Antarctica where no terrestrial mammals inhabit,the early Eocene climate was characterized by warmer temperatures and a biologically diverse environment rich in primary producers,dominated by nothofagus forests,encompassing both deciduous and evergreen forests,which supported a diverse assemblage of continental vertebrates.

关键词： Astrapotheria Antarctodon Eocene Seymour Island La Meseta Formation

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Thermo-and pH-sensitive Polymer with Pendant Spacer-linked Imidazole cycles

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chinese Journal of Polymer Science 2024年第4期42卷 437-445页

作者： natalya V.Zakharova Stanislav n.Zelinskiy Mariya S.Strelova Elena n.Danilovtseva Vadim V.Annenkov Institute of Macromolecular compounds of the Russian Academy of Sciences Saint Petersburg199004Russia Limnological Institute of Siberian Branch of the Russian Academy of Sciences Irkutsk664033Russia

By the reaction of poly(acryloyl chloride) with n-(3-aminopropyl)imidazole, poly(n-(3-(1H-imidazol-1-yl)propyl)acrylamide) was synthesized. The new polymer contains an imidazole ring removed from the main chain by a spacer of five bonds. The structure and purity, molecular weight, hydrodynamic and thermosensitive properties of the obtained sample were studied by1H-and13c-nMR, FTIR spectroscopy, acid-base titration, light scattering, turbidimetry and viscometry. The observed ability of the imidazole-containing polymer to form and destroy associates in water-salt solutions at pH 6.6-7.4 and temperatures of 29-48℃ indicates that these are promising candidates for designing complex biomedical systems. The new polymer is able to form complexes with oligo-DnA more actively than poly(1-vinylimidazole), which is of interest for gene delivery applications. The polymer cross-linked with epichlorohydrin gives micro-relief coatings on the plastic surface, and the modified surface is able to attach negatively charged objects. This thermo-and pH-sensitive polymer modification can be applied to create finely controlled surfaces for cell culturing.

关键词： Imidazole-containing polymer Thermolability pH-sensitivity The modified surface DnA immobilization

Hepatic angiotensin-converting enzyme 2 expression in metabolic dysfunction-associated steatotic liver disease and in patients with fatal cOVID-19

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World Journal of Gastroenterology 2024年第31期30卷 3705-3716页

作者： Angus K Jacobs Steven D Morley Kay Samuel Katie Morgan Lyndsey Boswell Timothy J Kendall David A Dorward Jonathan A Fallowfield Peter c Hayes John n Plevris Hepatology Laboratory University of EdinburghEdinburgh EH164SBUnited Kingdom Scottish national Blood Transfusion Service Jack Copland CentreEdinburgh EH144BEUnited Kingdom Institute for Regeneration and Repair University of EdinburghEdinburgh EH164UUUnited Kingdom Edinburgh Pathology University of EdinburghEdinburgh EH164SBUnited Kingdom

BAcKGROUnD Metabolic dysfunction-associated steatotic liver disease(MASLD),characterised by hepatic lipid accumulation,causes inflammation and oxidative stress accompanied by cell damage and *** injury(LI)is also frequently reported in patients hospitalised with coronavirus disease 2019(cOVID-19),while preexisting MASLD increases the risk of LI and the development of cOVID-19-associated *** of injury at the cellular level remain unclear,but it may be significant that severe acute respiratory syndrome coronavirus 2(SARS-coV-2)which causes cOVID-19,uses angiotensin-converting expression enzyme 2(AcE2),a key regulator of the‘anti-inflammatory’arm of the renin-angiotensin system,for viral attachment and host cell *** To determine if hepatic AcE2 levels are altered during progression of MASLD and in patients who died with severe *** AcE2 protein levels and localisation,and histological fibrosis and lipid droplet accumulation as markers of MASLD were determined in formalin-fixed liver tissue sections across the MASLD pathological spectrum(isolated hepatocellular steatosis,metabolic dysfunction-associated steatohepatitis(MASH)+/-fibrosis,end-stage cirrhosis)and in post-mortem tissues from patients who had died with severe cOVID-19,using AcE2 immunohistochemistry and haematoxylin and eosin and picrosirius red staining of total collagen and lipid droplet areas,followed by quantification using machine learning-based image pixel *** AcE2 staining is primarily intracellular and concentrated in the cytoplasm of centrilobular hepatocytes and apical membranes of bile duct ***,AcE2 protein levels are elevated in non-fibrotic MASH compared to healthy controls but not in the progression to MASH with fibrosis and in ***2 protein levels and histological fibrosis are not associated,but AcE2 and liver lipid droplet content are significantly correlated across the MASLD *** A

关键词： Metabolic dysfunction-associated steatotic liver disease Angiotensin-converting enzyme 2 Immunohistochemistry cOVID-19 cOVID-19-associated cholangiopathy

Old-growth mixed dipterocarp forests show variable losses and gains in aboveground biomass and standing carbon over forty years

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Forest Ecosystems 2024年第1期11卷 14-23页

作者： Sisira Ediriweera champika Bandara Tithira Lakkana Shanika Jayasinghe David Woodbury Arun Dayanandan B.M.P.Singhakumara Xiangcheng Mi I.A.U.n.Gunatilleke c.V.S.Gunatilleke Mark SAshton Department of Science and Technology Uva Wellassa UniversityBadullaSri Lanka The Forest School Yale School of the EnvironmentYale UniversityNew HavenCT06511USA Department of Forestry and Environmental Science University of Sri JayewardenepuraNugegodaSri Lanka State Key Laboratory of Vegetation and Environmental change Institute of BotanyChinese Academy of SciencesBeijing100093China Botany Department University of PeradeniyaPeradeniyaSri Lanka

Background:no studies have documented long-term trends in aboveground biomass(AGB)for mixed-dipterocarp forests(MDF),the dominant rain forest type in tropical wet equatorial *** our study,we sought to document such trends over forty years across three sites representing lowland to lower montane ***:To do this,we established fifty 100 m×25 m plots in 1978 across three sites sampled along an elevation gradient,identified as mature old-growth *** measured trees for diameter at breast height that we identified to species and *** took wood samples to calculate species wood-specific *** re-measured plots in 1998 and again in ***:We show standing AGB for all sites combined to be 517.52 Mg·ha^(-1)in 1978,but this declined by 17%over 40 years to 430.11 Mg·ha^(-1).no differences exist among sites in AGB primarily because of considerable within site variation;but interactions of time with site show declines across sites were not uniform,one remained about the *** few species represented a high proportion of the AGB with the top five species comprising between 34%and 65%,depending upon site and year *** species,Mesua nagassarium,represented a disproportionately large amount of AGB and decline over time,particularly at the low elevation ***:Our results are directly relevant to estimating AGB and standing carbon sequestered in *** study is the first to demonstrate varying but overall,declining trends in amounts of AGB among forests making predictions of biomass and standing carbon in MDF difficult over wide regions.

关键词： Western ghats Shorea spp. Southeast Asia Sri Lanka Tropical rain forest Wood specific gravity

Solar-assisted photocatalytic water splitting using defective UiO-66 solids from modulated synthesis

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nano Research 2024年第5期17卷 4134-4150页

作者： celia M.Rueda-navarro María cabrero-Antonino Paula Escamilla Valentín Díez-cabanes Dong Fan Pedro Atienzar Belén Ferrer Ignacio Vayá Guillaume Maurin Herme G.Baldoví Sergio navalón Departamento de Química Universitat Politècnica de ValènciaCamino de Vera s/nValencia 46022Spain Instituto de ciencia Molecular(IcMOL) Universitat de ValènciaPaterna 46980Spain IcGM Univ.MontpellierCNRSENSCMMontpellier34095France Instituto de Tecnología Química(UPV-cSIc) Universitat Politècnica de ValènciaAvenida de los Naranjos s/nValencia 46022Spain

Metal-organic frameworks(MOFs)are attracting increasing interests as photocatalysts for solar-driven hydrogen production from *** paper reports on a comparative study of using either acetic acid(AA)or trifluoroacetic acid(TFA)as the representative UiO-66 organic modulators for synthesizing visible light responsive UiO-66(Zr)-X(X:nH_(2) or nO_(2))photocatalysts for water *** results show that photocatalytic hydrogen generation from a water/methanol mixture can be improved by varying the nature and amount of the modulator employed to prepare the different UiO-66(Zr)-X(X:nH_(2) or nO_(2))solid ***-66(Zr)-nH_(2) was the most active photocatalyst,followed by UiO-66(Zr)-nO_(2),both prepared with 12 equivalents of AA with respect to the organic *** UiO-66(Zr)-nH_(2) solid was more active than the parent MOF in photocatalytic overall water splitting(OWS)(H_(2) and O_(2) production of 450 and 160μmol·g^(-1),respectively,in 5 h;apparent quantum yield(AQY)at 400 nm of 0.06%)in the absence of methanol and compares favourably with analogous *** on the photocatalytic activity of the most active solids of both series was obtained by means of a series of techniques,including ultraviolet-visible(UV-vis)diffuse reflectance,X-ray photoelectron spectroscopy(XPS),laser flash photolysis(LFP),electron spin resonance(ESR),photoluminescence and photoelectrochemical measurements together with density functional theory(DFT)*** results showed that organic acid modulators can be used to enhance the photocatalytic activity of missing linker UiO-66 defective materials in solar-powered water splitting.

关键词： heterogeneous photocatalysis metal-organic frameworks(MOFs) UiO-66 materials carboxylic acid modulators water splitting solar light

nonlinear-Optical Analogies in nuclear-Like Soliton Reactions:Selection Rules,nonlinear Tunneling and Sub-Barrier Fusion–Fission

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chinese Physics Letters 2024年第8期41卷 1-7页

作者： T.L.Belyaeva V.n.Serkin Universidad Autonoma del Estado de Mexico Av.Instituto Literario 100C.P.50000TolucaMexico Benemerita Universidad Autonoma de Puebla Av.4 Sur 104C.P.72001PueblaMexico

The main goal of our study is to reveal unexpected but intriguing analogies arising between optical solitons and nuclear physics,which still remain hidden from *** consider the main cornerstones of the concept of nonlinear optics of nuclear reactions and the well-dressed repulsive-core *** the base of this model,we reveal the most intriguing properties of the nonlinear tunneling of nucleus-like solitons and the soliton selfinduced sub-barrier transparency *** describe novel interesting and stimulating analogies between the interaction of nucleus-like solitons on the repulsive barrier and nuclear sub-barrier *** main finding of this study concerns the conservation of total number of nucleons(or the baryon number)in nuclear-like soliton *** show that inelastic interactions among well-dressed repulsive-core solitons arise only when a“cloud”of“dressing”spectral side-bands appears in the frequency spectra of the *** property of nucleus-like solitons is directly related to the nuclear density distribution described by the dimensionless small shape-squareness *** the Fourier spectra of nucleus-like solitons are similar to the nuclear form *** show that the nuclear-like reactions between well-dressed solitons are realized by“exchange”between“particle-like”side bands in their spectra.

关键词： solitons soliton nonlinear

Academic productivity correlates with industry earnings in foot and ankle fellowship programs in the United States:A retrospective analysis

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World Journal of Orthopedics 2024年第2期15卷 129-138页

作者： Albert T Anastasio Anthony n Baumann Kempland c Walley Kyle J Hitchman conor O’neill Jonathan Kaplan Samuel B Adams Department of Orthopedic Surgery Duke University HospitalDurhamNC 27710United States college of Medicine Northeast Ohio Medical UniversityRootstownOH 44272United States Department of Orthopedic Surgery University of MichiganAnn ArborMI 48109United States School of Osteopathic Medicine Campbell UniversityLillingtonNC 27546United States

BAcKGROUnD The study investigates the connection between academic productivity and industry earnings in foot and ankle orthopedic surgery *** metrics like the H-index and Open Payments Database(OPD)data,it addresses a gap in understanding the relationship between scholarly achievements and financial outcomes,providing a basis for further exploration in this specialized medical *** To elucidate the trends between academic productivity and industry earnings across foot and ankle orthopedic surgery fellowship programs in the United *** This study is a retrospective analysis of the relationship between academic productivity and industry earnings of foot and ankle orthopedic surgery fellowships at an individual faculty and fellowship *** productivity was defined via H-index and recorded from the Scopus *** earnings were recorded from the *** Forty-eight foot and ankle orthopedic surgery fellowships(100%of fellowships)in the United States with a combined total of 165 physicians(95.9%of physicians)were *** individual physician(n=165)total life-time earnings reported on the OPD website was United States Dollar(USD)451430.30±1851084.89(range:USD 25.16-21269249.85;median:USD 27839.80).Mean physician(n=165)H-index as reported on Scopus is 14.24±12.39(range:0-63;median:11).There was a significant but weak correlation between individual physician H-index and individual physician total life-time earnings(Pn’s rho=0.334)and a significant and moderate positive correlation between combined fellowship H-index and total life-time earnings per fellowship(P=0.004,Spearman’s rho=0.409).cOncLUSIOn There is a significant and positive correlation between academic productivity and industry earnings at foot and ankle orthopedic surgery fellowships in the United *** observation is true on an individual physician level as well as on a fellowship level.

关键词： Sunshine act Foot and ankle Orthopedic surgery Orthopedic fellowship Industry earnings

chemosensitizing Effect of Monk Fruit Extract on Human Bladder cancer cells

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Journal of cancer Therapy 2024年第6期15卷 250-264页

作者： Sensuke Konno Jonathan wong Andrew Penunuri Kelvin Zheng Muhammad choudhury Department of Urology New York Medical College Valhalla New York USA

The outcomes of chemotherapy have been unsatisfactory with the palpable side effects. We hypothesized that natural products might help improve chemotherapy with few side effects. Recently, we came across the bioactive extracts of monk fruit (Siraitia grosvenori) with anticancer activity. We then investigated if these extracts might have chemosensitizing effect to improve the efficacy of drugs clinically used today. Four different drugs, cisplatin (cPL), carboplatin (cBL), mitomycin c (MMc), and gemcitabine (GEM), were used in this study. Human bladder cancer T24 cells were treated with each drug itself or drug combined with either LLE or MOG (two types of monk fruit extracts). cell viability was determined to assess anticancer effect and also explored the anticancer mechanism of such combinations, focusing on the status of glycolysis, cell cycle, and chromatin structure. cell viability test showed that all drugs had anticancer activity, reducing cell viability, but only cPL showed the enhanced anticancer effect when combined with LLE (not with MOG). The rest of three drugs had no such effects with LLE or MOG. The cPL/LLE combination was found to disrupt glycolysis, by inhibiting hexokinase activity, resulted in the decreased ATP synthesis. This combination also blocked the cell cycle progression, due to a G1 cell cycle arrest. Moreover, the two epigenetic regulators, DnA methyltransferase and histone deacetylase, were inactivated with the combination, indicating chromatin modifications. Ultimately, these treated cells were found to undergo apoptosis. In conclusion, anticancer activity of cPL can be significantly enhanced with LLE. This chemosensitizing effect is attributed to the glycolysis inhibition, a G1 cell cycle arrest, and chromatin modifications, ultimately leading to apoptosis. Thus, certain natural products such as LLE could be used as an adjuvant agent in current chemotherapy, improving the drug efficacy but minimizing side effects.

关键词： Monk Fruit Anticancer Bladder cancer chemosensitization Lakanto

Investigating Stability Properties for Transition Metal carbonate Precursors Using Universal cluster Expansion Technique(UncLE)as cathodes for Li-Ion Batteries

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材料科学与工程（中英文A版） 2024年第1期14卷 26-33页

作者： Mogahabo Tebogo Morukuladi n.L.Lethole M.c.Masedi n.n.ngoepe P.E.ngoepe Materials Modelling centre University of LimpopoPrivate Bag x1106Sovenga 0727South Africa Department of Physics University of Fort HareAlice 5700South Africa

The universal cluster expansion technique was used in this study to determine the binary phase diagrams for the transition metal carbonate precursors McO3(M:Mn,ni,co).The use of mixed cathode materials in lithium-ion batteries such as nMc(ni,Mn and co)formulations,is a strategic approach to optimize performance,enhance safety and address cost and environmental considerations in the rapidly evolving field of energy *** study focuses on the cost issue related to lithium ion batteries by investigating the manganese rich nMc since manganese is more abundant and *** doped MncO3 with nickel and doped MncO3 with cobalt then ran cluster expansion calculations to generate binary *** binary phase diagrams generated indicated that doping MncO3 with nickel favours the Mn-rich side,while doping MncO3 with cobalt favours 50%Mn-rich and 50%*** further extracted the most stable structures from both binary diagrams and determined their electronic,mechanical and vibrational stabilities using DFT(density functional theory)calculations within the LDA(local gradient approximation)with Hubbard parameter(U).The electronic properties revealed that both materials are semiconductors due to their narrow energy band gap obtained while the mechanical properties showed that structures are mechanically stable since their necessary conditions for trigonal and triclinic systems were satisfied.

关键词： Binary phase diagrams mechanical properties electronic conductivity phonon dispersion curves.