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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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涂层和未涂层铝基体上接触应力的有限元模拟

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中国表面工程 2000年第1期13卷 27-31页

作者： J J moore r m souza G G W mustoe 徐桂珍 Advanced Coatings and Surface Engineering Laboratory(ACSEL) Colorado School of mines Division of Engineering Colorado School of mines 清华大学摩擦学研究所

基于对涂层/基体系统上产生的接触应力的分析，研究了软基体上薄膜的磨损行为。应用有限元法对由压头向涂层或未涂层铝基体施加正压力的情况进行模拟。先在没有薄膜的系统上对模型的精确性进行检验。然后通过改变薄膜的弹性模量比，开... 详细信息

基于对涂层/基体系统上产生的接触应力的分析，研究了软基体上薄膜的磨损行为。应用有限元法对由压头向涂层或未涂层铝基体施加正压力的情况进行模拟。先在没有薄膜的系统上对模型的精确性进行检验。然后通过改变薄膜的弹性模量比，开发出适用于铝基体上有两层硬薄膜试样的模型。同时还研究了薄膜厚度和载荷的影响。较厚的薄膜降低了模型上某些点的应力，但是增加了另一些点的应力。从弹性模量的角度来说，薄膜内的计算应力主要与薄膜的弹性模量有关，而通过改变薄膜的弹性模量比几乎不会使应力产生差异。

关键词：有限元模拟涂层接触应力薄膜磨损

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Synthesis Gas Production from Natural Gas on Supported Pt Catalysts

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Journal of Natural Gas Chemistry 2006年第1期15卷 21-27页

作者： mariana m. V. m. souza Octávio r. macedo Neto martin Schmal NUCAT/PEQ/COPPE

Auto-thermal reforming of methane, combining partial oxidation and reforming of methane with CO2 or steam, was carried out with Pt/Al2O3, Pt/ZrO2 and Pt/CeO2 catalysts, in a temperature range of 300-900℃. The auto-thermal reforming occurs in two simultaneous stages, namely, total combustion of methane and reforming of the unconverted methane with steam and CO2, with the O2 conversion of 100% starting from 450℃. For combination with CO2 reforming, the Pt/CeO2 catalyst showed the lowest initial activity at 800℃, and the highest stability over 40 h on-stream. This catalyst also presented the best performance for the reaction with steam at 800℃. The higher resistance to coke formation of the catalyst supported on ceria is due to the metal-support interactions and the higher mobility of oxygen in the oxide lattice.

关键词： methane steam reforming CO2 reforming partial oxidation auto-thermal reforming platinum catalyst ceria zirconia

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Increasing pancreatic cancer is not paralleled by pancreaticoduodenectomy volumes in Brazil:A time trend analysis

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Hepatobiliary & Pancreatic Diseases International 2019年第1期18卷 79-86页

作者： Lucila m Perrotta de souza Jessica PL moreira Homero S Fogaca José marcus raso Eulálio ronir r Luiz Heitor SP de souza Department of Internal medicine School of Medicine Federal University of Rio de Janeiro Institute of Public Health Studies (IESC) Federal University of Rio de Janeiro Department of Surgery School of Medicine Federal University of Rio de Janeiro D’Or Institute for research and Education

Background: Currently, surgical resection represents the only curative treatment for pancreatic cancer(PC), however, the majority of tumors are no longer resectable by the time of diagnosis. The aim of this study was to describe time trends and distribution of pancreaticoduodenectomies(PDs) performed for treating PC in Brazil in recent years. methods: Data were retrospectively obtained from Brazilian Health Public System(namely DATASUS) regarding hospitalizations for PC and PD in Brazil from January 2008 to December 2015. PC and PD rates and their mortalities were estimated from DATASUS hospitalizations and analyzed for age, gender and demographic characteristics. results: A total of 2364 PDs were retrieved. Albeit PC incidence more than doubled, the number of PDs increased only 37%. most PDs were performed in men(52.2%) and patients between 50 and 69 years old(59.5%). Patients not surgically treated and those 70 years or older had the highest in-hospital mortality rates. The most developed regions(Southeast and South) as well as large metropolitan integrated municipalities registered 76.2% and 54.8% of the procedures, respectively. LmIm PD mortality fluctuated, ranging from 13.6% in 2008 to 11.8% in 2015. Conclusions: This study suggests a trend towards regionalization and volume-outcome relationships for PD due to PC, as large metropolitan integrated municipalities registered most of the PDs and more stable mortality rates. The substantial differences between PD and PC increasing rates reveals a limiting step on the health system resoluteness. reduction in the number of hospital beds and late access to hospitalization, despite improvement in diagnostic methods, could at least in part explain these findings.

关键词： Pancreatic cancer Pancreaticoduodenectomy Time trend analysis Ecological study Hospitalization rates mortality rates

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Understanding source-sink interactions: Progress in model plants and translational research to crops

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molecular Plant 2023年第1期16卷 96-121页

作者： Laise rosado-souza ryo Yokoyama Uwe Sonnewald Alisdair r.Fernie max-Planck-Institute of molecular Plant Physiology Am Mühlenberg 114476 Potsdam-GolmGermany Department of Biochemistry University of Erlangen-NurembergStaudtstrasse 591058 ErlangenGermany

Agriculture is facing a massive increase in demand per hectare as a result of an ever-expanding population and environmental *** we have learned much about how environmental conditions and diseases impact crop yield,until recently considerably less was known concerning endogenous factors,including within-plant nutrient *** this review,we discuss studies of source-sink interactions covering both fundamental research in model systems under controlled growth conditions and how the findings are being translated to crop plants in the *** this respect we detail efforts aimed at improving and/or combining C3,C4,and CAm modes of photosynthesis,altering the chloroplastic electron transport chain,modulating photorespiration,adopting bacterial/algal carbon-concentrating mechanisms,and enhancing nitrogen-and water-use ***,we discuss how modulating TCA cycle activities and primary metabolism can result in increased rates of photosynthesis and outline the opportunities that evaluating natural variation in photosynthesis may *** source,transport,and sink functions are all covered in this review,we focus on discussing source functions because the majority of research has been conducted in this ***,considerable recent evidence,alongside the evidence from classical studies,demonstrates that both transport and sink functions are also incredibly important determinants of *** thus describe recent evidence supporting this notion and suggest that future strategies for yield improvement should focus on combining improvements in each of these steps to approach yield optimization.

关键词： photosynthesis assimilate transport nitrogen-use efficiency water-use efficiency source-sink natural variance transgenic intervention

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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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A novel ZnO/reduced graphene oxide and Prussian blue modified carbon paste electrode for the sensitive determination of rutin

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Science China Chemistry 2019年第2期62卷 262-270页

作者： Ozma J D'souza ronald J mascarenhas Ashis K Satpati Basavanakote m Basavaraja research and Development Centre Bharathiar University Electrochemistry research Group Department of Chemistry St.Joseph's College Analytical Chemistry Division Bhabha Atomic Research Centre Anushakthi Nagar Trombay Department of Chemistry PES University

A carbon paste modified sensor based on a novel composite of zinc oxide nanoparticles deposited on reduced graphene oxide(ZnO-rGrO) and Prussian blue(PB) was drop-cast(ZnO-rGrO-PB/mCPE) for the sensitive estimation of rutin(rtn) at pH *** high surface area of ZnO-rGrO and electrocatalytic property of PB promotes the oxidation of rtn. Field emission scanning electron microscope(FE-SEm) and energy-dispersive X-ray spectroscopy(EDX) techniques were employed to confirm the deposition of ZnO-rGrO and PB on carbon paste electrode(CPE). The ability of ZnO-rGrO-PB/mCPE in charge transfer at the interface was investigated using electrochemical impedance spectroscopy(EIS). The heterogeneous rate constant(ks) and the charge transfer coefficient(α) have been calculated as 6.08 s^(-1) and 0.74 respectively. This sensor showed a wide linear response for rtn from 7.0×10^(-8)to 7.0×10^(-6) m and 7.0×10^(-6) to 1.0×10^(-4) m with a limit of detection(2.05±0.04)×10^(-8) m(S/N=3). The application of ZnO-rGrO-PB/mCPE was found in the analysis of rtn in fruit juice samples using standard addition method. This sensor showed good reproducibility, stability, selectivity and sensitivity.

关键词： rutin zinc oxide nanoparticles reduced graphene oxide Prussian blue modified carbon paste electrode ascorbic acid

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molecular mechanisms of viral hepatitis induced hepatocellular carcinoma

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World Journal of Gastroenterology 2020年第38期26卷 5759-5783页

作者： Simmone D'souza Keith CK Lau Carla S Coffin Trushar r Patel Department of microbiology Immunologyand Infectious DiseasesCumming School of MedicineUniversity of CalgaryCalgary T2N 1N4ABCanada Department of Chemistry and Biochemistry Alberta RNA Research and Training InstituteUniversity of LethbridgeLethbridge T1K3M4ABCanada

Chronic infection with viral hepatitis affects half a billion individuals worldwide and can lead to cirrhosis,cancer,and liver *** cancer is the third leading cause of cancer-associated mortality,of which hepatocellular carcinoma(HCC)represents 90%of all primary liver *** tumors like HCC are complex and have heterogeneous tumor genomic profiles contributing to complexity in diagnosis and *** infection with hepatitis B virus(HBV),hepatitis delta virus(HDV),and hepatitis C virus(HCV)are the greatest etiological risk factors for *** to the significant role of chronic viral infection in HCC development,it is important to investigate direct(viral associated)and indirect(immune-associated)mechanisms involved in the pathogenesis of *** mechanisms used by HBV,HCV,and HDV that drive hepatocarcinogenesis include persistent liver inflammation with an impaired antiviral immune response,immune and viral protein-mediated oxidative stress,and deregulation of cellular signaling pathways by viral *** integration to promote genome instability is a feature of HBV infection,and metabolic reprogramming leading to steatosis is driven by HCV *** current review aims to provide a brief overview of HBV,HCV and HDV molecular biology,and highlight specific viral-associated oncogenic mechanisms and common molecular pathways deregulated in HCC,and current as well as emerging treatments for HCC.

关键词： Chronic viral infection Hallmarks of cancer Hepatocellular carcinoma Hepatitis B virus Hepatitis C virus Hepatitis delta virus co-infection molecular mechanisms Viral hepatitis

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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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Coarse corn particles cause a negative effect on eggshell quality of semi-heavy laying hens

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Animal Nutrition 2019年第4期5卷 432-434页

作者： Vanessa r.m.Oliveira Alex m.V.Arruda Aurora S.melo Davyd H.souza Joao B.F.souza-Junior raimunda T.V.Fernandes Joao P.A.F.Queiroz Department of Animal Sciences Universidade Federal Rural do Semi-AridoMossoro 59625900Brazil Department of Animal Science Federal University of CearaFortalezaCEP 60455-760Brazil

One of the possible ways to optimize the productive performance of poultry is through the physical processing of ingredients,which can improve the use of nutrients in these *** this context,this study was to evaluate the effects of different corn particle sizes in diets on the productive performance and egg quality of semi-heavy laying *** naked neck laying hens were used from 24 weeks of age and distributed in a completely randomized *** diets in different treatments contained corn grain ground into sieves with a diameter of 2,4,or 8 mm to provide corn particles with a geometric mean diameter(GmD) of 605(fine),1,030(medium),and 2,280 μm(coarse),*** feed and leftovers were weighed daily throughout the experimental period to determine the feed intake and feed *** corn particle sizes did not affect any aspect of the productive performance of hens,except for feed *** fed fine and medium corn particles exhibited higher values for egg yolk color,eggshell weight,and eggshell *** is suggested that semi-heavy laying hens should be fed mash diets containing corn particles with GmD from 605 to 1,030 μm,because coarse corn particles cause a negative effect on eggshell quality.

关键词： Egg quality Geometric mean diameter Productive performance Poultry nutrition

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