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Changes in calcium accumulation and utilization efficiency and their impact on recycling, immobilization, and export across the oil palm cycle

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Oil Crop science 2024年第3期9卷 143-150页

作者： viégas I.D.J.M. souza L.C.D. Ferreira E.v.D.O. Costa M.G. Nogueira G.A.D.s. Nascimento v.R.D. Oliveira Neto C.F.D. Capanema Campus Federal Rural University of the Amazon (UFRA) Av. Barão de Capanema Caixa D'agua 5514-6434 Pará Brazil Center of Agricultural and Environmental sciences Federal University of Maranhão (UFMA) Chapadinha BR-222 km 04 SN Boa Vista 65500000 Maranhão Brazil Capitão Poço Campus Federal Rural University of the Amazon (UFRA) Tv. Pau Amarelo S/n - Vila Nova Capitão Poço 68650-000 Pará Brazil department of soil science São Paulo State University (Unesp) School of Agricultural and Veterinarian Sciences Jaboticabal Via de Acesso Prof. Paulo Donato Castelane Castellane - S/N - Vila Industrial São Paulo 14884-900 Brazil Institute of Agricultural sciences (ICA) Federal Rural University of the Amazon (UFRA) Estr. Principal da Ufra 2150 Curió-Utinga Belém 66077-580 Pará Brazil

Effective calcium (Ca) management is crucial for optimizing oil palm cultivation and enhancing crop yield. This study aimed to gain insights into the dynamics of Ca concentration, accumulation, exportation, immobilization, and recycling in various oil palm organs relative to plant age. The experiment was conducted at the Agropalma enterprise site in the northeastern region of Pará state, Brazil, evaluating seven plant age treatments: 2, 3, 4, 5, 6, 7, and 8 years old. Employing a completely randomized design with four replications. The results demonstrated an age-related increase in Ca concentration in petioles, rachis, arrows, male inflorescences, peduncles, and fruits. Furthermore, Ca accumulation exhibited an upward trend in all organs with progressing plant age. Notably, the study revealed an enhanced Ca use efficiency across all plant organs in correlation with the age of oil palm cultivation. These findings underscore the dynamic nutritional demands of oil palm, influencing Ca immobilization, cycling, and export throughout its developmental stages. © 2024 the Oil Crop Research Institute, Chinese Academy of Agriculture sciences

关键词： Amazon Ca cycling Ca export Ca immobilization Ca use efficiency Elaeis guineensis Jacq. Plant nutrition

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study of the Conversion of Postconsumer Polystyrene on CeO<sub>2sub>/HZsM-5 Type Materials

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Journal of Materials science and Chemical Engineering 2024年第4期12卷 29-41页

作者： Mirna Oliveira sant’Ana Anne Michelle Garrido Pedrosa Marcelo José Barros de souza Graduate Program in Chemical Engineering at UFs Federal University of Sergipe (UFS) S&#227o Crist&#243v&#227o Brazil department of Chemistry Federal University of Sergipe S&#227o Crist&#243v&#227o Brazil

The catalytic conversion of polystyrene (Ps) was studied in the presence of the materials type HZsM-5, CeO2, 10% CeO2/HZsM-5 and 20% CeO2/HZsM-5, which were characterized by scanning electron microscopy (sEM), X-ray d... 详细信息

The catalytic conversion of polystyrene (Ps) was studied in the presence of the materials type HZsM-5, CeOsub>2sub>, 10% CeOsub>2sub>/HZsM-5 and 20% CeOsub>2sub>/HZsM-5, which were characterized by scanning electron microscopy (sEM), X-ray diffraction (XRD) and nitrogen adsorption at 77K. The catalytic tests were performed via thermogravimetric analysis (TG) at heating rates of 5, 10 and 20˚C minsup>−1sup> in a temperature range from 30˚C to 900˚C. For the tests, a ratio of 30% by mass of each catalytic material mixed with Ps was used and the activation energy of the degradation process was determined by the vyazovkin method. The obtained results showed that the addition of the catalyst to the Ps in general reduced its degradation temperature. The 10% CeOsub>2sub>/HZsM-5 catalyst showed greater efficiency, as it resulted in lower activation energy for Ps degradation. Thus, the combination of CeOsub>2sub> with HZsM-5 resulted in materials with potential for application in the catalytic degradation of polystyrene and the results indicate that the production of a composite material can be a good strategy to generate an increase in catalytic activity and a decrease in energy process activation.

关键词： HZsM-5 Zeolite Cerium Oxide Polystyrene Pyrolysis

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Physiological Effect of Kinetin on the Photosynthetic Apparatus and Antioxidant Enzymes Activities During Production of Anthurium

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Horticultural Plant Journal 2018年第5期4卷 182-192页

作者： de MOURA Fabiana B. vIEIRA Marcos R. da s. sIMOEs Adriano do N. FERREIRA-sILvA sérgio L. de souza carl.s a.v. de souza Eduardo s. da ROCHA Alexandre T. da sILvA Luzia F. JUNIOR Miguel A. Faculty of Agronomy Federal University of Pará Postgraduate Program in Plant Production Serra Talhada Academic UnitFederal Rural University of Pernambuco department of Production vegetable Unidade Academica de GaranhusFederal Rural University of Pernambuco

The results observed in the literature raise the hypothesis according to which cytokinin plays important roles in photosynthetic metabolisms and antioxidant enzymes. Thus, the study aimed to evaluate the effect of foliar application of the isolated cytokinin kinetin at the production cycle, seeking to analyze its effects on enzyme activity and photosynthetic parameters. The plants treated with CK presented reduction of leaf CO_2 assimilation rate(Pn) and stomatal conductance(Gs), while that transpiration rate(Tr) was unaffected. The internal CO_2 concentrations decreased with the increase in cytokinin levels, but were maintained under CK 50 mg·L^(-1). The plants treated with CK 75 mg·L^(-1) was verified higher carboxylation efficiency(Pn/Ci), which was associated to values of CO_2 assimilation and transpiration unaltered. Apparent electron transport rate showed variations in the concentration of 25 mg·L^(-1). Considering the study of enzyme activity, on the other hand, it cannot be stated that kinetin has an effective action in delaying oxidative damage. It presents mixed results, since an efficiency in the application of cytokinin was not observed, presenting induction levels of ascorbate peroxidase activity. Thus, further research is needed to determine more precisely the effects of kinetin on gas exchange and antioxidant enzymes in anthurium plants.

关键词： anthurium kinetin photosynthesis senescence plant hormone oxidative stress

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Pancreatic fistula after pancreatectomy:Evolving definitions,preventive strategies and modern management

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World Journal of Gastroenterology 2008年第38期14卷 5789-5796页

作者： shailesh v shrikhande Melroy A D'souza department of GI and HPB surgical Oncology Tata Memorial HospitalMumbai 400-012 India

Pancreatic resection is the treatment of choice for pancreatic malignancy and certain benign pancreatic disorders. However, pancreatic resection is technically a demanding procedure and whereas mortality after a pancreaticoduodenectomy is currently volume centers, post-operative morbidity is considerable, about 30%-50%. At present, the single most significant cause of morbidity and mortality after pancreatectomy is the development of pancreatic leakage and fistula (PF). The occurrence of a PF increases the length of hospital stay and the cost of treatment, requires additional investigations and procedures, and can result in life-threatening complications. There is no universally accepted definition of PF that would allow standardized reporting and proper comparison of outcomes between different centers. However, early recognition of a PF and prompt institution of appropriate treatment is critical to the prevention of potentially devastating consequences. The present article, reviews the evolution of post resection pancreatic fistula as a concept, and discusses evolving definitions, the current preventive strategies and the management of this problem.

关键词： Pancreatic fistula Pancreaticoduodenectomy Pancreatic anastomosis Pancreatic anastomotic failure Complications

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spouting behavior of binary particle mixtures of different densities: Fluid dynamics and particle segregation

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Particuology 2019年第1期17卷 58-66页

作者： K.G. santos R.C. santana D.L. souza v.v. Murata M.A.s. Barrozo Federal University ofTriangulo Mineiro Chemical Engineering DepartmentUniverdecidade CampusUberabaMGBrazil Federal University of Uberlandia Chemical Engineering SchoolUberlandiaMG. Brazil

Numerous industrial applications of spouted beds involve a mixture of granular particles, where differences in particle size, density, and shape can cause particle segregation, affecting the quality of flow and decreasing product homogeneity. The aim of this study was to investigate the particle segregation and fluid dynamics of a conical spouted bed operating with a binary mixture of particles of different densities. Using glass beads and polyethylene particles with a diameter of 4 mm, we determined the effects of the mass fraction of denser particles and static bed height on the minimum spouting condition and mixture index. The pressure drop and airflow in the minimum spouting condition increased with an increase in bed height or jetsam concentration. Regarding particle segregation, the jetsam particles tended to concentrate near the bottom, at the spout–annulus interface because they have a shorter trajectory than the lighter particles in the fountain region. Jetsam-rich mixtures with high initial static bed heights exhibited more efficient particle mixing, excluding those at the bottom of the bed.

关键词： density segregation spouted bed Binary mixtures

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Unwrapping reworked crust at the Columbia supercontinent margin within central southern Amazon Craton using multi-source geophysics and geochronology data synergy

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Geoscience Frontiers 2022年第3期13卷 35-52页

作者： João G.Motta P.G.Betts v.T.Meira.v.G.Trevisan C.R.de souza Filho Institute of Geosciences University of CampinasCampinasSão PauloBrazil Camborne school of Mines University of ExeterPenryn CampusPenrynCornwallUnited Kingdom school of Earth Atmosphere and EnvironmentMonash University(Clayton Campus)ClaytonVICAustralia Anglo American Níquel Brasil Ltda. Avenida Interlândia502 QD 87LST 68 e 10GoiâniaGoiásBrazil

The geometry and evolution of pre-existing basement in accretionary belts bordering supercontinents are often *** interpretation of long-wavelength potential field satellite data can image deep crust structure,improving our understanding of lithospheric processes that formed these margins ***,we present a multidisciplinary interpretation of the lithospheric architecture of the central southern Amazon Craton,a fragment of an accretionary belt at the southwestern Columbia supercontinent ***-borne gravity and magnetic data,airborne magnetic data,passive seismic(v_(p)/v_(s) ratio,crustal thickness)and seismic tomography data reveals that basement terranes from the interior of the craton extend into the accretionary margin of *** demonstrate a.v.rtically heterogeneous structure with an underlying strongly reworked pre-Columbia tectonic wedge that sustained prolonged modification during the supercontinent assembly as corroborated by Nd isotope and geochronology *** isotope data suggest that the protracted orogenic wedge was influenced by subduction angle shifts over time,including addition of substantial juvenile material during slab retreat *** interplay promoted Craton growth at the supercontinent margin while keeping a subtle record of the pre-existing *** findings point to the possible misrepresentation of basement extension and geometry of supercontinent margins elsewhere.

关键词： satellite gravity satellite magnetics Columbia Accretionary belt Amazon Craton Geochronology

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Investigation of Galactic open cluster remnants： the case of NGC 7193

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Research in Astronomy and Astrophysics 2017年第1期17卷 31-54页

作者： Mateus de souza Angelo Joao Francisco Coelho dos santos Jr Wagner Jose Barbosa Corradi Francisco Ferreira de souza Maia Andres Eduardo Piatti departamento de Fisica ICEx Universidade Federal de Minas Gerais Av. Antonio Carlos 6627 31270-901 Belo Horizonte MG Brazil Observatorio Astronomico Universidad Nacional de Cordoba Laprida 854 5000 Cordoba Argentina Consejo Nacional de Investigaciones Cientificas y Tecnicas Av. Rivadavia 1917 C1033AAJ Buenos AiresArgentina

Galactic open clusters （OCs） that survive the early gas-expulsion phase are gradually de- stroyed over time by the action of disruptive dynamical processes. Their final evolutionary stages are characterized by a poorly populated concentration of stars called an open cluster remnant （OCR）. This study is devoted to assessing the real physical nature of the OCR candidate NGC 7193. GMOs/Gemini spectroscopy of 53 stars in the inner target region were obtained to derive radial velocities and at- mospheric parameters. We also employed photometric and proper motion data. The analysis method consists of the following steps：（i） analysis of the statistical resemblance between the cluster and a set of field samples with respect to the sequences defined in color-magnitude diagrams （CMDs）; （ii） a 5-dimensional iterative exclusion routine was employed to identify outliers from kinematical and posi- tional data; （iii） isochrone fitting to thes× （J - Ks） CMD of the remaining stars and the dispersion of spectral types along empirical sequences in the （J - H） × （H - Ks） diagram were checked. A group of stars was identified for which the mean heliocentric distance is compatible with that obtained via isochrone fitting and whose metallicities are compatible with each other. Fifteen of the member stars observed spectroscopically were identified together with another 19 probable members. Our results indi- cate that NGC 7193 is a genuine OCR, of a once very populous OC, for which the following parameters were derived： d = 501±46 pc, t = 2.5±1.2 Gyr, （[Fe/H]） = -0.17±0.23 and E（B-v） = 0.05±0.05. Its luminosity and mass functions show depletion of low mass stars, confirming the OCR is in a dynam- ically evolved state.

关键词： open cluster remnants - Galactic open clusters

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Nanocellulose-based porous materials: Regulation and pathway to commercialization in regenerative medicine

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Bioactive Materials 2023年第11期29卷 151-176页

作者： Filipe v.Ferreira Alana G.souza Rubina Ajdary Lucas P.de souza Jo˜ao H.Lopes Daniel s.Correa Gilberto siqueira Hernane s.Barud derval dos s.Rosa Luiz H.C.Mattoso Orlando J.Rojas Nanotechnology National Laboratory for Agriculture(LNNA) Embrapa Instrumentation-Rua XV de Novembro1452S˜ao CarlosSP13560-979Brazil Center for Engineering Modelingand Applied Social Sciences(CECS)Federal University of ABC(UFABC)Santo Andr´eBrazil department of Bioproducts and Biosystems School of Chemical EngineeringAalto UniversityP.O.Box 16300AaltoEspooFIN-00076Finland College of Engineering and Physical sciences Aston Institute of Materials ResearchAston UniversityBirminghamUK department of Chemistry Division of Fundamental Sciences(IEF)Technological Institute of Aeronautics(ITA)S˜ao Jose dos CamposSPBrazil Laboratory for Cellulose&Wood Materials Empa-Swiss Federal Laboratories for Materials Science and TechnologyÜberlandstrasse 1298600DübendorfSwitzerland Biopolymers and Biomaterials Laboratory(BIOPOLMAT) University of Araraquara(UNIARA)Araraquar114801-340S˜ao PauloBrazil Bioproducts Institute Department of Chemical&Biological EngineeringDepartment of Chemistry andDepartment of Wood ScienceThe University of British Columbi12360 East MallVancouverBCV6T 1Z3Canada

We review the recent progress that have led to the development of porous materials based on cellulose nanostructures found in plants and other resources. In light of the properties that emerge from the chemistry, shape and structural control, we discuss some of the most promising uses of a plant-based material, nanocellulose, in regenerative medicine. Following a brief discussion about the fundamental aspects of self-assembly of nanocellulose precursors, we review the key strategies needed for material synthesis and to adjust the architecture of the materials (using three-dimensional printing, freeze-casted porous materials, and electrospinning) according to their uses in tissue engineering, artificial organs, controlled drug delivery and wound healing systems, among others. For this purpose, we map the structure-property-function relationships of nanocellulose-based porous materials and examine the course of actions that are required to translate innovation from the laboratory to industry. such efforts require attention to regulatory aspects and market pull. Finally, the key challenges and opportunities in this nascent field are critically reviewed.

关键词： Cellulose nanofibrils Cellulose nanocrystals Regenerative medicine Biomaterial sustainable materials Green nanomaterials

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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 carl.s 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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Acromyrmex ameliae sp. n. （Hymenoptera： Formicidae）： A new social parasite of leaf-cutting ants in Brazil

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Insect science 2007年第3期14卷 251-257页

作者： DANIvAL JOsE de souza ILKA MARIA FERNANdes sOAREs TEREZINHA MARIA CAsTRO deLLA LUCIA Institut de Recherche sur la Biologie de 1'Insecte Université Francois Rabelais Tours France departamento de Biologia Animal Laboratório de Ecologia de Comunidades Departamento de Biologia Geral Universidade Federal de Vicosa MG 36570-000 Brazil

The fungus-growing ants （Tribe Attini） are a New World group of〉 200 species, all obligate symbionts with a fungus they use for food. Four attine taxa are known to be social parasites of other attines. Acromyrmex （ Pseudoatta） argentina argentina and Acromyrmex （Pseudoatta） argentina platensis （parasites of Acromyrmex lundi）, and Acromyrmex sp. （a parasite of Acromyrmex rugosus） produce no worker caste. In contrast, the recently discovered Acromyrmex insinuator （a parasite of Acromyrmex echinatior） does produce workers. Here, we describe a new species, Acromyrmex ameliae, a social parasite of Acromyrmex subterraneus subterraneus and Acromyrmex subterraneus brunneus in Minas Gerais, Brasil. Like A. insinuator, it produces workers and appears to be closely related to its hosts. similar social parasites may be fairly common in the fungus-growing ants, but overlooked due to the close resemblance between parasite and host workers.

关键词： Acromyrmex leaf-cutting ants social evolution social parasitism

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