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Operator Splitting for Three-Phase Flow in Heterogeneous Porous Media

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Communications in Computational Physics 2009年第6期6卷 72-84页

作者： e.Abreu J.Douglas F.furtado F.Pereira Instituto Nacional de Matematica Pura e Aplicada RJ 22460-320Brazil Department of Mathematics Purdue UniversityWest LafayetteIN 47907-1395USA Department of Mathematics University of WyomingLaramieWY 82071-3036USA Department of Mathematics and School of energy Resources University of WyomingLaramieWY 82071-3036USA

We describe an operator splitting technique based on physics rather than on dimension for the numerical solution of a nonlinear system of partial differential equations which models three-phase flow through heterogeneous porous *** model for three-phase flow considered in this work takes into account capillary forces,general relations for the relative permeability functions and variable porosity and permeability *** our numerical procedure a high resolution,nonoscillatory,second order,conservative central difference scheme is used for the approximation of the nonlinear system of hyperbolic conservation laws modeling the convective transport of the fluid *** scheme is combined with locally conservative mixed finite elements for the numerical solution of the parabolic and elliptic problems associated with the diffusive transport of fluid phases and the pressure-velocity *** numerical procedure has been used to investigate the existence and stability of nonclassical shock waves(called transitional or undercompressive shock waves)in two-dimensional heterogeneous flows,thereby extending previous results for one-dimensional flow *** experiments indicate that the operator splitting technique discussed here leads to computational efficiency and accurate numerical results.

关键词： Operator splitting three-phase flow heterogeneous porous media central differencing schemes mixed finite elements

Retreived bacteria from Noctiluca miliaris (green) bloom of the northeastern Arabian Sea

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Chinese Journal of Oceanology and Limnology 2013年第1期31卷 10-20页

作者： BASU Subhajit MATONDKAR SG Prabhu furtado Irene Department of Microbiology Goa University National Institute of Oceanography (CSIR-India)

In recent years, seasonal blooms of the dinoflagellate Noctiluca miliaris have appeared in the open-waters of the northern Arabian Sea （NAS）. This study provides the first characterization of bacteria from a seasonal bloom of green Noctiluca ofNAS （20°N-17°N and 64°e-70°e）, during the spring-inter-monsoon cruise ofSagar Sampada 253, in March 2007. Bacterial growth as assessed by most-probable number （MPN） and plate counts, revealed ＇variable-physiotypes＇ over a wide range of salinities （0%-25% w/v NaC1）, pH levels （5-8.5）, and organic nutrient strengths, in comparison to non-bloom waters. MPN indices of bacteria in surface waters of bloom stations ＊DWK and ＊PRB, corresponded to （3.08-4.41）×103 cells/mL at 3.5% NaC1 （w/v）, and （2.82-9.49）× 102 cells/mL at 25% （w/v） NaC1 in tryptone-yeast extract broth （TYe）. Plate counts were （1.12-4） × 106 CFU/mL at 0% （w/v） NaC1, （1.28-3.9） × 106 CFU/mL at 3.5% （w/v） NaC1, and （0.4- 7）×104 CFU/mL at 25% NaC1 （w/v） on TYe. One-tenth-strength Zobell＇s gave （0.6-3.74）× 105 CFU/mL at pH 5 to （3.58-7.5）× 105 CFU/mL at pH 8.5. These bacteria were identified to the genera Bacillus, Cellulomonas, Staphylococcus, Planococcus, Dietzia, Diergibacillus, Micrococcus, Sporosarcinae, Leucobacter, and Halomonas. The identity of three strains （GUFBSS253N2, GUFBSS253N30, and GUFBSS253N84） was confirmed through 16S rDNA sequence homology as Bacillus cohnii, Bacillusflexus, and Bacillus cereus. The -2-3-fold higher plate counts of culturable bacteria from the open-waters of the NAS indicate that these bacteria could critically determine the biogeochemical dynamics of the bloom and its milieu. The role of these bacteria in sustaining/terminating the bloom is under evaluation.

关键词： northeastern Arabian Sea (NAS) green Noctiluca bloom retrievable bacteria

Imperfect mimicry of host begging calls by a brood parasitic cuckoo:a cue for nestling rejection by hosts?

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Current Zoology 2021年第6期67卷 665-674页

作者： Hee-Jin NOH ros GLOAG Ana V.LeITAO Naomi e.LANGMORe Research School of Biology Australian National UniversityCanberra ACT 0200Australia School of Life and environmental Sciences University of SydneySydneyNSW 2006Australia School of Biosciences University of MelbourneParkville VIC 3010Australia

Coevolutionary interactions between avian brood parasites and their hosts often lead to the evolution of discrimination and rejection of parasite eggs or chicks by hosts based on visual cues,and the evolution of visual mimicry of host eggs or chicks by brood *** may also base rejection of brood parasite nestlings on vocal cues,which would in turn select for mimicry of host begging calls in brood parasite *** cuckoos that exploit multiple hosts with different begging calls,call structure may be plastic,allowing nestlings to modify their calls to match those of their various hosts,or fixed,in which case we would predict either imperfect mimicry or divergence of the species into host-specific *** our study of the little bronze-cuckoo(LBC)Chalcites minutillus and its primary host,the large-billed gerygone Gerygone magnirostris,we tested whether:(1)hosts use nestling vocalizations as a cue to discriminate cuckoo chicks;(2)cuckoo nestlings mimic the host begging calls throughout the nestling period;and(3)the cuckoo begging calls are plastic,thereby facilitating mimicry of the calls of different *** found that the begging calls of LBCs are most similar to their gerygone hosts shortly after hatching(when rejection by hosts typically occurs)but become less similar as cuckoo chicks get *** call structure may be used as a cue for rejection by hosts,and these results are consistent with gerygone defenses selecting for age-specific vocal mimicry in cuckoo *** found no evidence that LBC begging calls were plastic.

关键词： begging call bronze-cuckoo brood parasitism coevolution gerygone

Synthesis of a cardanol-amine derivative using an ionic liquid catalyst

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Frontiers of Chemical Science and engineering 2016年第3期10卷 425-431页

作者： Atanu Biswas Carlucio R. Alves Maria T. S. Trevisan roseane L. e. da Silva ros.layne e furtado Zengshe Liu H. N. Cheng USDA Agricultural Research Service National Center for Agricultural Utilization Research Peoria IL 61604 USA Chemistry Department State University of Ceara Itaperi Campus 60740-020 Fortaleza-CE Brazil Chemistry Department Federal University of Ceara Pici Campus 60455-760 Fortaleza-CE Brazil embrapa Tropical Agroindustry Rua Dra. Sam Mesquita Planalto Pici 60511-110 Fortaleza-CE Brazil USDA Agricultural Research Service Southern Regional Research Center New Orleans LA 70124 USA

Cardanol is a biobased raw material derived from cashew nut shell liquid. In order to extend its utility, new derivatives and additional applications are useful. In this work cardanol was first epoxidized, and a novel aniline derivative prepared from it under mild reaction conditions with the help of an ionic liquid catalyst. The reaction chemistry was studied by using nuclear magnetic reso- nance. The resulting aminohydrin adduct showed antiox- idant property and should also be a useful synthon for further reactions. As an example, the aminohydrin was shown to undergo a condensation reaction with formalde- hyde to form a prepolymer, which could be further reacted to form thermosetting resins.

关键词： cardanol epoxidation aminohydrin aniline,ionic liquid aniline-formaldehyde

Heterologous expression of LamA gene encoded endo-β-1,3- glucanase and CO2 fixation by bioengineered Synechococcus sp. PCC 7002

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Frontiers of environmental Science & engineering 2017年第2期11卷 115-122页

作者： Di Li Swati Yewalkar Xiaotao Bi Sheldon Duff Dusko Posarac Heli Wang layne A. Woodfin Jan-Hendrik Hehemann Sheila C. Potter Francis e. Nano School of Water Resources and environment China University of Geosciences Beijing 100083 China Department of Chemical and Biological engineering University of British Columbia Vancouve V6T 1Z3 Canada Department of Biochemistry and Microbiology University of Victoria Victoria V5Z 4H4 Canada

The gene for the catalytic domain of thermostable endo-β-1,3-glucanase （laminarinase） LamA was cloned from Thermotoga maritima MSB8 and heterologously expressed in a bioengineered Synechococcus sp. PCC 7002. The mutant strain was cultured in a photobioreactor to assess biomass yield, recombinant laminarinase activity, and CO2 uptake. The maximum enzyme activity was observed at a oH of 8.0 and a temoerature of 70℃. At a CO2 concentration of 5%, we obtained a maximum specific growth rate of 0.083 h^-1 a biomass productivity of 0.42 g· L^-1·d^-1 a blomass concentration of 3.697 g.L^-1 , and a specific enzyme activity of the mutant strain of 4.325 ***^- 1 dry mass. All parameters decreased as CO2 concentration increased from 5% to 10% and further to 15% CO2, except enzyme activity, which increased from 5% to 10% CO2. However, the mutant culture still 1 1 grew at 15% CO2 concentration, as reflected by the blomass productwlty （0.26 g.L .d ）, biomass concentration （2.416 g.L^- 1）, and specific enzyme activity （3.247 ***^-1 dry mass）.

关键词： Synechococcus sp. PCC 7002Thermotoga maritimaLamA geneendo-β-1 3-glucanaseCO2 fixation

Managing type 2 diabetes:targeting a microbial enzyme as a novel treatment option

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Signal Transduction and Targeted Therapy 2024年第1期9卷 3-5页

作者： Anikó Keller-Pintér Tamás Korcsmáros Tibor Vellai Department of Biochemistry Albert Szent-Györgyi Medical SchoolUniversity of SzegedSzeged6720Hungary Department of Metabolism Digestion and ReproductionImperial College LondonLondonW120NNUK Quadram Institute Bioscience Norwich Research ParkNorwichNR47UQUK Department of Genetics Eötvös Loránd University(ELTE)Budapest1117Hungary Hungarian Research Network HUN-ReN-eLTe Genetics Research Group Budapest1117Hungary

In a recent Science article,Wang and colleagues showed that the dipeptidyl peptidase 4(DPP4)enzyme produced by the gut microbiota can interfere with the effect of host glucagon-like peptide-1(GLP-1)involved in stimulating insulin secretion,and the specific inhibitor of microbial DPP4(mDPP4),combined with clinical inhibitors of host DPP4 isoenzymes,further promotes blood glucose homeostasis.1 These results point out why certain patients respond inadequately to an antidiabetic medication.

关键词： homeostasis stimulating clinical

Downregulation of the Basic Peroxidase Isoenzyme from Zinnia elegans by Gibberellic Acid

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Journal of Integrative Plant Biology 2010年第2期52卷 244-251页

作者： María Josefa López Núez-Flores Jorge Gutirrez Laura V.Gómez-ros esther Novo Uzal Mariana Sottomayor Alfonso ros Barceló Department of Plant Biology University of MurciaE-30100MurciaSpain Department of Plant Biology University of La CoruaE-15071La CorunaSpain IBMC University of Porto4150 PortoPortugal

Hypocotyl formation during the epigeal germination of seedlings is under strict hormonal regulation. In a 3 d old Zinnia elegans seedling system, gibberellic acid （GA3） exerts an opposite effect to that exerted by light on hypocotyl photomorphogenesis because GAz promotes an etiolated-like growth with an inhibition of radial （secondary） growth. For this reason, the effect of GA3 on the basic peroxidase isoenzyme from Z. elegans （ZePrx）, an enzyme involved in hypocotyl lignin biosynthesis, was studied. The results showed that GA3 reduces ZePrx activity, similarly to the way in which it reduces seedling secondary growth. This hormonal response is supported by the analysis of the ZePrx promoter, which contains four types of GA3-responsive ***： the W Box/O2S; the Pyr Box; the GARe; and the Amy Box. Taken together, these results suggest that ZePrx is directly regulated by GA3, with this effect matching the inhibitory effect of GA on the hypocotyl secondary growth.

关键词： GA Downregulation of the Basic Peroxidase Isoenzyme from Zinnia elegans by Gibberellic Acid cis Figure

The versatility of mesenchymal stem cells:From regenerative medicine to COVID,what is next?

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BIOCeLL 2022年第4期46卷 913-922页

作者： THAÍS CASAGRANDe PAIM MÁRCIA rosÂNGeLA WINK Laboratório de Biologia Celular Universidade Federal de Ciências da Saúde de Porto Alegre(UFCSPA)Porto Alegre90050-170Brazil

Mesenchymal stem cells(MSCs)play key roles in regenerative medicine by promoting tissue *** can be isolated from different adult tissues and they are able to differentiate into several *** to their antiinflammatory,angiogenic and immune-modulatory properties,MSCs are suitable for tissue engineering applications and,when associated with biomaterials,their benefits can be ***,recently,MSCs have been studied for new clinical applications,such as in the treatment of patients with *** regenerative potential has been attributed to their secretome,which comprises extracellular matrix,soluble proteins and several elements,including the release of extracellular *** though,in order to explore all their therapeutic potential,it is still necessary to advance in the investigation of their basic cell biology characteristics.

关键词： Mesenchymal stem cells Regenerative medicine Secretome Biomaterials extracellular vesicles

Lower bounds on the minimum distance in Hermitian one-point differential codes

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Science China Mathematics 2013年第7期56卷 1449-1455页

作者： KORCHMros Gábor NAGY Gábor Pétery Dipartimento di Matematica e Informatica Università della Basilicata Bolyai Institute University of Szeged

Korchmaros and Nagy [Hermitian codes from higher degree places. J Pure Appl Algebra, doi： 10. 1016/***.2013.04.002, 2013] computed the Weierstrass gap sequence G（P） of the Hermitian function field Fq2 （H） at any place P of degree 3, and obtained an explicit formula of the Matthews-Michel lower bound on the minimum distance in the associated differential Hermitian code CΩ（D, mP） where the divisor D is, as usual, the sum of all but one 1-degree Fq2-rational places of Fq2 （H） and m is a positive integer. For plenty of values of m depending on q, this provided improvements on the designed minimum distance of CΩ（D, mP）. Further improvements from G（P） were obtained by Korchmaros and Nagy relying on algebraic geometry. Here slightly weaker improvements are obtained from G（P） with the usual function-field method depending on linear series, Riemann-Roch theorem and Weierstrass semigroups. We also survey the known results on this subject.

关键词： AG code Weierstrass gap Hermitian curve