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The Puesto Piris Formation: Evidence of basin-development in the North Patagonian Massif during crustal extension associated with Gondwana breakup

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Geoscience Frontiers 2019年第1期10卷 299-314页

作者： Leonardo Strazzere Daniel A.Gregori Leonardo Benedini paulo Marcos Mercedes v.Barros Mauro C.Geraldes Cecilia Pavon Pivetta Instituto Geológico del Sur Consejo Nacional de Investigaciones Científicas y Técnicas Av Cátedra de Geología Minera Universidad Nacional del Sur Cátedra de Geología Argentina Universidad Nacional del Sur Av Cátedra de Geofísica Departamento de Geología Universidad Nacional del Sur Av Departamento de Geología Regional Facultad de Geología Universidad Estatal de Rio de Janeiro

The Marifil volcanic Complex, exposed in the eastern North Patagonian Massif, Argentina, includes up to 550 m of red conglomerates, sandstones, black siltstones, limestones, and reworked tuff of the Puesto Piris Formation. The basal part of this unit, which was deposited in high-gradient topographic relief, is composed of conglomerates and sandstones with thin layers of reworked tuffs. The lithofacies associations of the basal part indicate that the depositional mechanisms were mantled and gravitational *** middle part of the unit consists of fine sandstones, limestones, and black siltstones that were deposited in low-energy fluvial and lacustrine environments. The outcrops are located along the NEe SW direction and the major thickest units represented by limestones and siltstones, occur near the southeastern border of this NEeS W depocenter. Since the rhyolitic and trachytic lava flows and tuffs of the Marifil volcanic Complex are interbedded with the sedimentary sequences of the Puesto Piris Formation,both units are coeval. Zircon Ue Pb age was obtained for a trachytic lava flow(193.4 ±3.1 Ma) suggesting that sedimentation and volcanism are Sinemurian. This extensional episode was recorded in the eastern,western, and southwestern sectors of the North Patagonian Massif, and is possibly associated with the Gondwana supercontinent breakup.

关键词： Puesto Piris Formation Early Jurassic North Patagonian Massif

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Proportionally Modular Diophantine Inequalities and Their Multiplicity

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Acta Mathematica Sinica,English Series 2010年第11期26卷 2059-2070页

作者： José Carlos ROSALES Manuel Batista BRANCO paulo vASCO Departamento de lgebra Universidad de Granada Departamento de Matemática Departamento de Matemática Universidade de Trás-os-Montes e Alto Douro

Let I be an interval of positive rational numbers. Then the set S （I） = T ∩ N, where T is the submonoid of （q0＋, ＋） generated by T, is a numerical semigroup. These numerical semigroups are called proportionally modular and can be characterized as the set of integer solutions of a Diophantine inequality of the form ax rood b 〈 cx. In this paper we are interested in the study of the maximal intervals I subject to the condition that S （I） has a given multiplicity. We also characterize the numerical semigroups associated with these maximal intervals.

关键词： Numerical semigroup Diophantine inequality multiplicity Frobenius number

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Ray Structure of the Coronal Streamer Belt and Its Manifestation as Sharp Large Peaks of Solar Wind Plasma Density at the Earth's Orbit

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空间科学学报 2005年第5期25卷 321-328页

作者： M. v. Eselevich v. G. Eselevich Z. q. Zang Institute of Solar-Terrestrial Physics Siberian Branch Russian Academy of Sciences Irkutsk 664033 Russia Center for Space Science and Applied Research Chinese Academy of Sciences Beijing 100080 China

The white-light corona calibrated data with processing level L1 from the LASCO-C2/SOHO instrument, and data from the Wind spacecraft with one-hour and one-minute time resolution on quasi-stationary slow (v between 300-450 km/s at the Earth's orbit) the Solar Wind (SW) parameters in the absence of sporadic SW streams are examined. Within distances from the Sun's center less than R in the range of 20-30 Rs,(Rs, the solar radius), slow wind is known as the streamer belt, and at larger distances it is called the Heliospheric Plasma Sheet (HPS). It is shown that the streamer belt comprises a sequence of pairs of rays. In general, ray brightnesses in each pair can differ, and the magnetic field is oppositely directed in them. The neutral line of the radial magnetic field of the Sun runs along the belt between the rays of each of the *** area in which the streamer belt intersects the ecliptic plane and which lies at the central meridian, will be recorded at the earth's orbit with a time delay of 5-6 days, in the form of one or several peaks with Nmax ＞ 10 cm-3. Furthermore, the simplest density profile of the portion of the HCS has the form of two peaks of a different or identical amplitude . The such a profile is observed in cases where the angle of intersection of the streamer belt with the ecliptic plane near the Sun is sufficiently large, i.e. close to 90°. The two-ray structure of the cross-section of the streamer-belt moves from the Sun to the Earth, it retains not only the angular size of the peaks but also the relative density variations, and the position of the neutral line(sector boundary) in between. At the Earth's orbit the ray structure of the streamer belt provides the source for sharp (i.e. with steep fronts of a duration of a few minutes or shorter) solar wind plasma density peaks (of a duration of several hours) with maximum values Nmax ＞ 10 cm-3.

关键词： Corona Solar wind Streamer belt

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Boundary Plasma Turbulence Simulations for Tokamaks

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Communications in Computational Physics 2008年第10期4卷 949-979页

作者： X.q.Xu M.v.Umansky B.Dudson P.B.Snyder Lawrence Livermore National Laboratory L-630P.O.Box 8087000 East Ave.LivermoreCA 94550USA Institute of Fusion Theory and Simulation ZhejiangUniversityHangzhou 310027China Department of Physics University of YorkHeslingtonYorkYO105DDUK General Atomics 13-303P.O.Box 85608San DiegoCA 92186-5608USA.

The boundary plasma turbulence code BOUT models tokamak boundaryplasma turbulence in a realistic divertor geometry usingmodified Braginskii equations for plasma vorticity,density(ni),electron and ion temperature(Te,Ti)and *** BOUT code solves for the plasma fluid equations in a three dimensional(3D)toroidal segment(or a toroidal wedge),including the region somewhat inside the separatrix and extending into the scrape-off layer;the private flux region is also *** this paper,a description is given of the sophisticated physical models,innovative numerical algorithms,and modern software design used to simulate edgeplasmas in magnetic fusion energy *** BOUT code’s unique capabilities and functionality are exemplified via simulations of the impact of plasma density on tokamak edge turbulence and blob dynamics.

关键词： Plasma turbulence simulation plasma two-fluids equation field-aligned coordinates plasma blobs

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Loss of Notch signaling in skeletal stem cells enhances bone formation with aging

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Bone Research 2023年第4期11卷 737-750页

作者： Lindsey H.Remark Kevin Leclerc Malissa Ramsukh Ziyan Lin Sooyeon Lee Backialakshmi Dharmalingam Lauren Gillinov vasudev v.Nayak paulo El Parente Margaux Sambon Pablo J.Atria Mohamed A.E.Ali Lukasz Witek Alesha B.Castillo Christopher Y.Park Ralf H.Adams Aristotelis Tsirigos Sophie M.Morgani Philipp Leucht Department of Orthopaedic Surgery NYU Robert I.Grossman School of MedicineNew YorkNYUSA Applied Bioinformatics Laboratories NYU Grossman School of MedicineNew YorkNYUSA Institute of Comparative Molecular Endocrinology Ulm UniversityUlmGermany Max Planck Institute for Molecular Biomedicine Department of Tissue Morphogenesisand University of MünsterFaculty of MedicineD-48149 MünsterGermany Department of Biochemistry and Molecular Biology University of Miami Miller School of MedicineMiamiFLUSA Department of Pathology NYU Robert I.Grossman School of MedicineNew YorkNYUSA Biomaterials Division New York University College of DentistryNew YorkNYUSA Hansjörg Wyss Department of Plastic Surgery NYU Grossman School of MedicineNew York UniversityNew YorkNYUSA Department of Biomedical Engineering Tandon School of EngineeringNew York UniversityBrooklynNYUSA Department of Cell Biology NYU Robert I.Grossman School of MedicineNew YorkNYUSA

Skeletal stem and progenitor cells(SSPCs) perform bone maintenance and repair. With age, they produce fewer osteoblasts and more adipocytes leading to a loss of skeletal integrity. The molecular mechanisms that underlie this detrimental transformation are largely unknown. Single-cell RNA sequencing revealed that Notch signaling becomes elevated in SSPCs during aging. To examine the role of increased Notch activity, we deleted Nicastrin, an essential Notch pathway component, in SSPCs in vivo. Middle-aged conditional knockout mice displayed elevated SSPC osteo-lineage gene expression, increased trabecular bone mass, reduced bone marrow adiposity, and enhanced bone repair. Thus, Notch regulates SSPC cell fate decisions, and moderating Notch signaling ameliorates the skeletal aging phenotype, increasing bone mass even beyond that of young mice. Finally, we identified the transcription factor Ebf3 as a downstream mediator of Notch signaling in SSPCs that is dysregulated with aging, highlighting it as a promising therapeutic target to rejuvenate the aged skeleton.

关键词： Notch skeletal elevated

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Coagulation enhanced electrokinetic settling of mature fine oil sands tailings

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International Journal of Mining Science and Technology 2019年第2期29卷 199-208页

作者： Shriful Islam Julie q.Shang Department of Civil and Environmental Engineering The University of Western Ontario Department of Civil and Environmental Engineering Shahjalal University of Science and Technology

The mature fine oil sand tailings(MFT) remain as slurry in the tailings pond for long time. The dewatering and consolidation of MFT for sustainable management is an important task for the mining industry. The objective of this study is to accelerate electrokinetic settling of MFT solids in suspensions in presence of optimal coagulant. In the first phase, optimal coagulant and coagulant dosage for settling of suspension are identified, i.e., ferric chloride at 350 mg/L. It is found that the chemical treatment is not much effective; the final solid content of the sediment is only 6.48% from an initial of 5%. In the second phase,combined coagulation and electrokinetic treatment is carried out to enhance the settling effect. The direct electric current is applied in continuous and intermittent modes on MFT suspensions placed in electrokinetic cell. The results show the final solid content reaches 23.74% under the combined application of350 mg/L ferric chloride and 218.75 v/m applied voltage gradient in the continuous mode. The intermittent current mode with 40% save in power consumption produces a settled sediment having 20.84% final solid content.

关键词： Electrokinetics Electrophoresis Coagulation Settling voltage gradient MFT

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Cross-sections for the 27Al(γ,x)22Na multichannel reaction with the 28.3 Mev difference of reaction thresholds

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Chinese Physics C 2022年第6期46卷 129-137页

作者： O.S.Deiev I.S.Timchenko S.N.Olejnik v.A.Kushnir v.v.Mytrochenko S.A.Perezhogin National Science Center"Kharkov Institute of Physics and Technology" 1 Akademichna St.61108 KharkivUkraine

The bremsstrahlung flux-averaged cross-sections(σ(Eγmax))and the cross-sections per equivalent photon(σ(Eγmax)q)were first measured for the photonuclear multichannel reaction ^(27)Al(γ,x)22 Na at end-point bremsstrahlung gamma energies ranging from 35 Mev to 95 *** experiments were performed with the beam from the NSC KIPT electron linear accelerator LUE-40 using theγ-activation *** bremsstrahlung quantum flux was calculated with the GEANT4.9.2 program and was also monitored via the ^(100)Mo(γ,n)^(99)Mo *** flux-averaged cross-sections were calculated using the partial cross-sectionσ(E)values computed with the TALYS1.95 code for different level density *** is given to special features of calculating the cross-sectionsandq>for the case of the final nucleus ^(22)Na via several partial channels x:nα+dt+npt+2 n^(3) He+n2d+2 npd+2 p3 n.

关键词： bremsstrahlung flux-averaged cross-section bremsstrahlung end-point energy of 35-95 Mev activation and off-lineγ-ray spectrometric technique TALYS1.95 GEANT4.9.2

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Kinetic Rates of the Fischer Tropsch Synthesis on a Co/Nb_2O_5 Catalyst

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Journal of Natural Gas Chemistry 2006年第4期15卷 307-312页

作者： víctor R.Ahón paulo L.C.Lage Carlos D.D.de Souza Fabiana M.Mendes Martin Schmal Federal University of Rio de Janeiro Programa de Engenharia química COPPE/UFRJ C.P.6850221941-972Rio de JaneiroRJBrazil

The kinetics of the Fischer-Tropsch reaction over a Co/Nb2O5 catalyst in a fixed bed reactor was investigated experimentally. Experiments were carried out under isothermal and isobaric conditions （T=543 K, P=2.1 MPa） and under different conditions of several H2/CO feed molar ratio （0.49-4.79）, space velocities （0.2-3.8 h^-1）, mass of catalyst （0.3-1.5 g）, and CO conversion （10%-29%）. Synthesis gas conversion was measured and data were reduced to estimate the kinetic parameters for different Langmuir-Hinshelwood rate expressions. Differential and integral reactor models were used for the nonlinear regression of kinetics parameters. One of the rate equations could well explain the data. The hydrocarbon product distributions that were experimentally determined exhibited an unusual behavior, and a possible explanation was discussed.

关键词： Fischer-Tropsch natural gas kinetics selectivity

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Does bilioenteric anastomosis impair results of liver resection in primary intrahepatic lithiasis?

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World Journal of Gastroenterology 2010年第27期16卷 3423-3426页

作者： paulo Herman Marcos v Perini vincenzo Pugliese Julio Cesar Pereira Marcel Autran C Machado William A Saad Luiz AC D'Albuquerque Ivan Cecconello Department of Gastroenterology Hospital Das Clínicas-University of So Paulo Medical SchoolSo Paulo-SP-CEP 05403-000BrazilPaulo HermanPraa Santos Coimbra10So Paulo-SP-CEP 05614-050Brazil

AIM:To evaluate the long-term results of liver resection for the treatment of primary intrahepatic *** factors,especially the impact of bilioenteric anastomosis on recurrence of symptoms were ***:Forty one patients with intrahepatic stones and parenchyma fibrosis/atrophy and/or biliary stenosis were submitted to liver *** was associated with a Roux-en-Y hepaticojejunostomy in all patients with bilateral stones and in those with unilateral disease and dilation of the extrahepatic biliary duct(>2 cm).Late results and risk factors for recurrence of symptoms or stones were ***:There was no operative *** a mean follow-up of 50.3 mo,good late results were observed in 82.9% of patients;all patients submitted to liver resection alone and 58.8% of those submitted to liver resection and hepaticojejunostomy were free of symptoms(P=0.0006).Patients with unilateral and bilateral disease showed good late results in 94.1% and 28.6%,respectively(P<0.001).CONCLUSION:Recurrence of symptoms in patients with hepaticojejunostomy showed that this may not be the ideal *** studies are needed to establish the best treatment for patients with bilateral stones or unilateral disease and a dilated extrahepatic duct.

关键词： Biliary lithiasis Bilioenteric anastomosis Cholangitis Intrahepatic lithiasis Liver resection

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In vivo study of conductive 3D printed PCL/MWCNTs scaffolds with electrical stimulation for bone tissue engineering

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Bio-Design and Manufacturing 2021年第2期4卷 190-202页

作者： Edney P.e Silva Boyang Huang Júlia v.Helaehil paulo R.L.Nalesso Leonardo Bagne Maraiara A.de Oliveira Gabriela C.C.Albiazetti Ali Aldalbahi Mohamed El-Newehy Milton Santamaria-Jr Fernanda A.S.Mendonça paulo Bártolo Guilherme F.Caetano Postgraduate Program in Biomedical Sciences University Center of Hermínio Ometto Foundation-FHOArarasSao PauloBrazil Department of Mechanical Aerospace and Civil EngineeringSchool of EngineeringUniversity of ManchesterManchester M139PLUK King Abdullah Institute for Nanotechnology King Saud UniversityRiyadh 11451Saudi Arabia

Critical bone defects are considered one of the major clinical challenges in reconstructive bone *** combination of 3D printed conductive scaffolds and exogenous electrical stimulation(ES)is a potential favorable approach for bone tissue *** this study,3D conductive scaffolds made with biocompatible and biodegradable polycaprolactone(PCL)and multi-walled carbon nanotubes(MWCNTs)were produced using the extrusion-based additive manufacturing to treat large calvary bone defects in *** results show that the use of PCL/MWCNTs scaffolds and ES contributes to thicker and increased bone tissue formation within the bone *** and mineralization are also significantly promoted using high concentration of MWCNTs(3 wt%)and ***,scaffolds favor the tartrate-resistant acid phosphatase(TRAP)positive cell formation,while the addition of MWCNTs seems to inhibit the osteoclastogenesis but present limited effects on the osteoclast functionalities(receptor activator of nuclear factor κβ ligand(RANKL)and osteoprotegerin(OPG)expressions).The use of ES promotes the osteoclastogenesis and RANKL expressions,showing a dominant effect in the bone remodeling *** results indicate that the combination of 3D printed conductive PCL/MWCNTs scaffold and ES is a promising strategy to treat critical bone defects and provide a cue to establish an optimal protocol to use conductive scaffolds and ES for bone tissue engineering.

关键词： Additive manufacturing Bone regeneration Bone remodeling Carbon nanotube Conductive scaffolds Electrical stimulation

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