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Germination strategies of annual and short-lived perennial species in the Arabian Desert

Journal of Arid Land 2020年第6期12卷 1071-1082页

作者： Arvind BHATT David J GALLACHEr paulo r m souza-filho Lushan Botanical Garden Chinese Academy of SciencesJiujiang 332900China School of Life and Environmental Sciences The University of SydneyNarrabri NSW 2390Australia multidisciplinary Center of Barra Federal University of Western BahiaBarra 47100-000Brazil

Germination timing is highly regulated in short-lived plant species since it strongly influences recruitment success of *** deserts,the spatiotemporal distribution of plant-available water is highly episodic and unpredictable,making winter months more favorable for seed germination when other abiotic conditions *** hypothesized that changes in photoperiod and thermoperiod would impact germination more in seeds that had undergone in situ *** assessed 21 annual and short-lived perennial species in the Arabian Desert to find(1)if seeds were dormant at maturity,(2)if in situ seed storage increased germination percentage compared with no storage,(3)if photoperiod and thermoperiod germination requirements were influenced by in situ storage,and(4)if a phylogenetic association in seed germination could be *** of each species collected in early 2017 were divided into two *** was tested for germination within one week(fresh seeds).The other was stored in situ at the maternal location(stored seeds)until October 2017 and tested for seed germination in the first week of *** germination was conducted in incubators at two thermoperiods(15℃/20℃ and 20℃/30℃;12 h/12 h),and two photoperiods(12 and 0 h light per day).results indicated that seed germination percentages of 13 species were significantly enhanced by in situ storage.A thermoperiod response was exhibited by stored,but not fresh *** exposure increased germination of fresh seeds but had only a minimal effect on stored *** traits exhibited no phylogenetic *** result indicated that selection pressure for germination strategy was stronger than that for taxonomic traits of these desert species.

关键词： desert species dormancy germination light temperature phylogeny

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Authigenic titanite in weathered basalts: Implications for paleoatmospheric reconstructions

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Geoscience Frontiers 2020年第6期11卷 2183-2196页

作者： Alexey A.Novoselov Dailto Silva Carlos roberto de souza filho Institute of Applied Economic Geology Universidad de ConcepcionConcepcionChile Institute of Geosciences University of CampinasCampinasSPBrazil

The stability of titanite is sensitive to temperature and partial pressure of *** finding of authigenic titanite grains in weathering regolith formed on Parana basalts,Brazil,under tropical climatic conditions,reveals the thermodynamically-driven conversion from calcite to titanite at elevated ambient *** unusual nowadays,this phase transition provides important implications for the understanding of silicate weathering in earlier geological *** types of secondary titanites were identified in the weathering profile of the study *** tiny grains of 10 μm are forming in the microscopic voids in the ***,large fractures filled with Fe-rich clay minerals contain bigger specimens of up to 170μ*** titanites of second type often coexist with chalcedony and *** carbonate minerals were found in the weathering *** sphene can be discriminated from other titanite types by its strong positive Eu anomaly,increased Al2 O3 content and low content of trace *** specific chemical composition and reactive transport modeling link this secondary mineral with dissolution of *** titanite precipitation is controlled by slow diffusion in poorly-aerated,highly-alkaline pore *** subaerial weathering of basaltic rocks provides a significant reservoir for atmospheric ***,the deposition of carbonate minerals is thermodynamically avoided at the stability field of *** demonstrate a complex feedback between CO2 and soil *** rise in pCO2 triggers the precipitation of calcite in the weathering regolith,but the greenhouse effect increasing the temperature can cease carbonate *** titanites were found in several paleosols and at least a part of them can be of weathering origin.

关键词： Titanite Sphene Calcite Paleosols Weathering Paleoclimates

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Continuous positive airway pressure acutely increases exercise duration in children with severe therapy-resistant asthma:a randomized crossover trial

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World Journal of Pediatrics 2021年第2期17卷 189-196页

作者： Claudia Silva Schindel Daniele Schiwe Joao paulo Heinzmann-filho Natalia Evangelista Campos paulo marcio Pitrez marcio Vinicius Fagundes Donadio Laboratory of Pediatric Physical Activity Centro Infant.Pontiffcia Universidade Catolica do Rio Grande do Sul(PUCRS)Av.Ipiranga6690.2°andarPorto AlegreRS CEP 90610-000.Brazil Hospital moinhos de Vento Porto AlegreBrazil and Centro InfantPontiffcia Universidade Catolica do Rio Grande do Sul(PUCRS)Porto Alegre.Brazil

Background Lower exercise tolerance is an important component of asthma and the possible effects of non-invasive ven-tilation on exercise capacity in individuals with severe therapy-resistant asthma(STrA)are *** study aimed to evaluate the immediate effect of continuous positive airway pressure(CPAP)on exercise tolerance in children with *** We performed a controlled,randomized,crossover clinical trial including subjects aged 6 to 18 years old diagnosed with ***,anthropometric and lung function data were *** participants in the intervention group(IG)used CPAP(PEEP 10cmH2O and FiO20.21)for a period of 40 *** in the control group(CG)used CPAP with mini-mum PEEP at 1 cmH20 also for 40 ***,subjects from both groups underwent cardiopulmonary exercise testing(CPET).After a 15-day washout period,on a subsequent visit,subjects participated in the opposite group to the initial *** Thirteen subjects with a mean age of 12.30±1.7 years were *** variables of peak expiratory flow(PEF)and forced expiratory volume in the first second(FEV1)before using CPAP and after performing CPET did not show sig-nificant *** CPET results,there was no significant difference(P=0.59)between groups at peak exercise for oxygen consumption—VO2(CG:33.4±6.3 and IG:34.5±5.9,mL kg^(-1)min^(-1)).However,the IG(12.4±2.1)presented a total test time(min)significantly(P=0.01)longer than the CG(11.5±1.3).Conclusion The results suggest that the use of CPAP before physical exercise increases exercise duration in children and adolescents with STrA.

关键词： Asthma Non-invasive ventilation Oxygen consumption Exercise test Exercise tolerance Exercise-induced bronchospasm

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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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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 vertically 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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Protective effect of ascorbic acid in experimental gastric cancer: reduction of oxidative stress

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World Journal of Gastroenterology 2003年第3期9卷 446-448页

作者： Claudia P.m.S.Oliveira paulo Kassab Fabio P.Lopasso Heraldo P.souza mariano Janiszewski Francisco r.m.Laurindo Kioshi Iriya Antonio A.Laudanna Department of Gastroenterology of medical School of University of So paulo (USP) So PauloBrazil Department of Emergency medicine of mcdical School of University of So paulo (USP) So PauloBrazil Heart Institute of medical School of University of So paulo (USP) So PauloBrazil Depatment of Pathology of medical School of University of So paulo (USP) So PauloBrazil

AIm;Oxidative stress participates in the cell carcinogenesis by inducing DNA *** aim was to assess whether ascorbic acid,an antioxidant,could have a role in preventing rOS(reactive Oxygen Species)generation in experimental gastric carcinoma in a rat model. mETHODS:Experimental gastric cancer was induced in twelve Wistar male rats(weighting 250-350 g)by profound duodeno-gastric reflux throught split *** rats were allocated to the following groups:Group Ⅰ(n=6) was the control;Group Ⅱ(n=6)which was mantained with daily intake of tape water with Vitamin C(30 mg/Kg).After 6 or 12 months,samples of gastric tumor or non tumor mucosa were taken from the anastomosis of both groups. Oxidative stress was measured by superoxide quantification through lucigenin-amplified chemiluminescence base and by staining with *** histopathologic confirmation of adenocarcinoma was made by eosin- hemathoxilin method. rESULTS:The intestinal type of gastric adenocarcinoma was microscopically identified in all animals of group Ⅰ whereas only 3 rats of group Ⅱ showed an adenocarcinoma without macroscopic evidence of *** cancers were located in the anastomosis in all *** luminescence from tumor gastric tissue generated 38.4±6.8 count per minute/mg/×10~6(mean±SD)and 14.9±4.0 count per minute/mg/×10~6,respectively,in group Ⅰ and Ⅱ animals(P robluetetrazolium method showed intense staining in tumor tissues but not in non neoplasic mucosa. CONCLUSION:Experimental gastric tumors seem to produce more reactive oxygen species than non neoplasic gastric *** reduction of oxidative stress and gastric tumor incidence in rats were induced by the intake of ascorbic ***,it may have a role in the prevention of gastric carcinoma. Oliveira CPmS Kassab P Lopasso FP souza HP Janiszewski m Laurindo Frm Iriya K Laudanna *** effect of ascorbic acid in experimental gastric cancer:reduction of oxidative *** J G

关键词： Animals Antioxidants Ascorbic Acid male Oxidative Stress rats rats, Wistar Stomach Neoplasms control

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Exploring the synthesis conditions to control the morphology of gold-iron oxide heterostructures

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Nano research 2019年第8期12卷 1781-1788页

作者： Pablo Tancredi Luelc souza da Costa Sebastian Calderon Oscar moscoso-Londono Leandro m. Socolovsky paulo J. Ferreira Diego muraca Daniela Zanchet marcelo Knobel Laboratory of Amorphous Solids INTECINFaculty of EngineeringUniversity of Buenos Aires - CONICETBuenos AiresCP C1063ACVArgentina Department of Inorganic Chemistry Institute of ChemistryUniversity of Campinas (UNICAMP)CP615413083-970CampinasSPBrazil Brazilian Nanotechnology National Laboratory (LNNano) Rua Giuseppe Maximo Scolfaro 10000CampinasSPBrazil International Iberian Nanotechnology Laboratory (INL) Av. Mestre Jose Veiga s/n4715-330 BragaPortugal “Gleb Wataghin” Institute of Physics University of Campinas (UNICAMP)CEP 13083-859CampinasSPBrazil Autonomous University of manizales Antigua Estacion del FerrocarrilManizalesCP 170001Colombia Facultad regional Santa Cruz Universidad Tecnoldgica Nacional - CIT Santa Cruz (CONICET)- Av delos Inmigrantes 555Rio GallegosSanta CruzArgentina materials Science and Engineering Program The University of Texas at AustinAustinTexas 78712USA

Gold-iron oxide nano-heterostructures with a clear and well-defined morphology were prepared via a seed-assisted method. The synthesis process and the events of heterogeneous nucleation during the decomposition of the iron precursor were carefully studied in order to understand the mechanism of the reaction and to tailor the architecture of the fabricated heterostructures. When employing Au seeds of 3 and 5 nm, nanoparticles with a dimer-like morphology were produced due to the occurrence of a single iron oxide nucleation event. Otherwise, multi-nucleation events could be favored by two mechanisms:(i) by the incorporation of a reducing agent and the slowing down of the heating protocol, leading to a core-shell system;(ii) by the increase of the Au seed size to 8 nm, leading to a flower-like system. Further increase of the Au seed size to 12 nm using similar synthesis conditions promotes the homogeneous nucleation and growth of the iron oxide phase, without formation of heterostructures. An in-depth study was performed on the gold-iron oxide heterostructures to confirm the epitaxial growth of the oxide domain over the Au seed and to analyze the elemental distribution of the components within the heterostructures. Finally, it was found that the modification of the plasmonic properties of the Au nanoparticles are strongly influenced by the architecture of the heterostructure, with a more pronounced damping effect for the systems produced after multi-nucleation events.

关键词： nanoparticles gold-iron oxide heterostructures heterogeneous nucleation epitaxial growth Hr-microscopy

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Effects of combined pre- and post-natal protein deprivation on the myenteric plexus of the esophagus of weanling rats:A histochemical,quantitative and ultrastructural study

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World Journal of Gastroenterology 2007年第26期13卷 3598-3604页

作者： Edson A Liberti ricardo BV Fontes Verginia m Fuggi Laura Bm maifrino romeu r souza Autonomic Nervous System Laboratory (VQm) Department of AnatomyInstitute of Biomedical SciencesUniversity of So Paulo So PauloBrazil

AIm: To evaluate the effects of protein deprivation on the myenteric plexus of the esophagus of weanling rats. mETHODS: Pregnant female Wistar rats were divided into 2 groups: nourished (N),receiving normal diet,and undernourished (D),receiving a protein-deprived diet,which continued after birth. At twenty-one days of age,13 esophagi from each group were submitted to light microscopy and morphometrical analysis employing the NADH diaphorase,NADPH diaphorase and acetylcholinesterase techniques. Three other esophagi from each group were evaluated with transmission electron microscopy (TEm). rESULTS: In both the NADH- and the NADPH-reactive mounts,the neurons of the N mounts were more intensely stained,while in the D esophagi only the larger neurons were reactive. many myenteric neurons of N were intensely reactive for AChE activity but only a few neurons of D exhibited these aspects. Ultrastructural analysis revealed that the granular reticulum of N showed large numbers of ribosomes aligned on the outer surface of its regularly arranged membrane while the ribosomes of D were disposed in clusters. The chromatin was more homogeneously scattered inside the neuron nucleus of N as well as the granular component of the nucleolus was evidently more developed in this group. Statistically significant differences between N and D groups were detected in the total estimated number of neurons stained by the NADPH technique. CONCLUSION: The morphological and quantitative data shows that feeding with protein-deprived diet in 21-d old rats induces a delay in the development of the myenteric neurons of the esophagus.

关键词： Enteric nervous system myenteric plexus Nutrition microscopy Electron Transmission Esopha-gus rat Wistar

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Fractionation of rare earth and other trace elements in crabs,Ucides cordatus,from a subtropical mangrove affected by fertilizer industry

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Journal of Environmental Sciences 2017年第4期29卷 69-76页

作者： Alice Bosco-Santos Wanilson Luiz-Silva Emmanoel Vieira da Silva-filho monique Dias Corrêa de souza Elton Luiz Dantas margareth Sugano Navarro State University of Campinas (UNICAmP) Institute of Geosciences Department of Geology and Natural Resources Campinas Sao Paulo 13083870 Brazil . Fluminense Federal University (UFF) Institute of Chemistry Department of Geochemistry Niteroi Rio de Janeiro 24900970 Brazil University of Brasília(UnB) Institute of Geosciences Department of Geology Brasflia Distrito Federal 70910900 Brazil

Fractionation of rare earth elements（rEE） and other trace metal concentrations（Th, U, Cd,Cr, Cu, Ni, Pb, and Zn） between mangrove sediments and claw muscles and shells of male crabs（Ucides cordatus） from a subtropical estuary highly impacted by fertilizer industry activities was investigated. This is the first record of rEE distribution in these organisms,and the results showed higher accumulations of these metals, U and Th in shells, probably related to the replacement of Ca during molting. Contents of Cd, Cr and Ni were similar in both tissues, but Cu, Zn and Pb were mostly accumulated in the claw muscle with concentrations above those considered safe for human consumption according to the Brazilian legislation. rEE fractionation was different in the analyzed tissues being softer in the shells. The results provided evidences that the water absorbed during molting controls the chemistry of rEE in shells. In contrast, the chemistry of rEE in the claw muscle, in which was observed preferential absorption of light rEE, is controlled by diet. rEE fractionation obtained for the claw muscles was closely correlated to the observed in the contaminated substrate and in materials related to the production of phosphate fertilizers（contamination source）, which supports their transference to this Ucides cordatus tissue without fractionation by the ingestion of sediments. Our results showed the potential use of crab tissues for monitoring rEE and trace element sources in mangrove areas, with claw muscle exhibiting the contaminant source fingerprint.

关键词： rare earth elements Trace metals Fertilizer contamination Crabs

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Plant growth and nutrient use efficiency of two native Fabaceae species for mineland revegetation in the eastern Amazon

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Journal of Forestry research 2020年第6期31卷 2287-2293页

作者： Silvio J.ramos markus Gastauer Simone K.mitre Cecı´lio F.Caldeira Joyce r.Silva Antonio E.Furtini Neto Guilherme Oliveira Pedro W.m.souza filho Jose´O.Siqueira Instituto Tecnolo´gico Vale Rua Boaventura da Silva955Belem 66055-090Brazil Departamento de Ciencia do Solo Universidade Federal de LavrasLavras 37200-000Brazil

The primary challenge of mineland revegetation is the establishment of species able to cope with low availability of nutrients,especially in steep slopes such as of mine *** evaluated plant growth response and nutrient use efficiency(NUE)of two promising native Fabaceae species(Dioclea apurensis—liana from metalliferous savannas;Bauhinia longipedicellata—tree from Amazon rainforest)from the Caraja´s mineral Province,eastern *** were grown separately in 2-kg pots filled with mining *** were fertilized with nitrogen,phosphorus,potassium(NPK),lime,and *** results showed increments on growth of both species when nutrients were applied to the mining *** showed increases in leaf area,plant height,stem diameter,and shoot dry mass production when NPK or NPK?micronutrients were applied,while *** was responsive to application of NPK?lime or NPK?lime?***,*** showed higher NUE than ***,especially at the lowest doses of N,P and *** findings may indicate a substantial advantage of *** for mineland revegetation,as this species may require lower nutrient inputs,being,therefore,a more sustainable way to revegetate degraded areas.

关键词： Fertilizer application mining soil Tropical forest Nutrient use efficiency

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