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Growth and phenotypic plasticity of two tropical tree species under low light availability

Journal of Plant Ecology 2021年第2期14卷 270-279页

作者： marúcia da cunha fagundes Ândrea Carla dalmolin Luciana Santos Lobo Ana Cristina Schilling martielly Santana dos Santos marcelo Schramm Mielke Departamento de Ciências Biológicas Universidade Estadual de Santa CruzIlhéusBABrazil Centro de Formação em Ciências Agroflorestais Universidade Federal do Sul da BahiaIlhéusBABrazil Departamento de Ciências Exatas e Tecnológicas Universidade Estadual de Santa CruzIlhéusBABrazil

Aims Screening tree species in tropical rainforest according to their shade tolerance is important to efficiently manage the native trees of economic significance in secondary forest enrichment *** objective of this study was to determine the whole-plant light compensation point(WPLCP)and compare the phenotypic plasticity in relation to growth and carbon allocation of Cariniana legalis and Gallesia integrifolia seedlings under low light *** Seedlings were cultivated for 77 days under conditions of five photosynthetically active radiation(PAR)(0.02,1.1,2.3,4.5 and 5.9 mol photons m^(−2)day^(−1))in three *** and carbon allocation variables were *** Findings Growth rates of *** were higher and lower than those of *** under 1.1 and 5.9 mol photons m^(−2)day^(−1),*** WPLCP differed significantly between the two *** accordance with the criteria of the shade tolerance classification for these two tropical tree species,our results showed that *** had lower WPLCP and phenotypic plasticity in terms of higher growth rates and greater shade tolerance than *** a practical point of view,we demonstrated that the differential linkage between growth and changing PAR between the two species can become a useful tool for comparing and selecting tree species in forest enrichment projects.

关键词： Cariniana legalis Gallesia integrifolia rainforest tropical tree seedlings relative distance plasticity index whole-plant light compensation point

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No evidence of HPV DNA in esophageal squamous cell carcinoma in a population of Southern Brazil

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World Journal of Gastroenterology 2013年第39期19卷 6598-6603页

作者： Luís Carlos Moreira Antunes Joo Carlos Prolla Antonio de Barros Lopes marta Pires da Rocha Renato Borges fagundes Programa de Pós-Graduao: Ciências em Gastroenterologia e Hepatologia - Universidade Federal do Rio Grande do Sul Porto AlegreRio Grande do Sul 90035-003Brasil Hospital Universitário de Santa maria - Universidade Federal de Santa maria Santa MariaRio Grande do Sul 97119-900Brasil Departamento de Clínica Médica - Universidade Federal de Santa maria Santa MariaRio Grande do Sul 97119-900Brasil

AIM:To investigate the association between human papillomavirus(HPV)and esophageal squamous cell carcinoma(ESCC)in southern ***:We studied 189 esophageal samples from125 patients from three different groups:(1)102 biopsies from 51 patients with ESCC,with one sample from the tumor and another from normal esophageal mucosa distant from the tumor;(2)50 esophageal biopsies from 37 patients with a previous diagnosis of head and neck squamous cell carcinoma(HNSCC);and(3)37 biopsies from esophageal mucosa with normal appearance from 37 dyspeptic patients,not exposed to smoking or alcohol ***-polymerase chain reaction(PCR)with the MY09/11 and GP5/6 L1primers was used to detect HPV L1 in samples fixed in formalin and stored in paraffin *** PCR reactions were performed with a positive control(cervicovaginal samples),with a negative control(Human Genomic DNA)and with a blank reaction containing all reagents except *** took extreme care to prevent DNA contamination in sample collection,processing,and ***:The histological biopsies confirmed the diagnosis of ESCC in 52 samples(51 from ESCC group and 1 from the HNSCC group)and classified as well differentiated(12/52,23.1%),moderately differentiated(27/52,51.9%)or poorly differentiated(7/52,13.5%).One hundred twenty-eight esophageal biopsies were considered normal(51 from the ESCC group,42 from the HNSCC group and 35 from dyspeptic patients).Nine had esophagitis(7 from the HNSCC and 2 from dyspeptic patients).Of a total of 189 samples,only 6 samples had insufficient material for PCR analysis:1 from mucosa distant from the tumor in a patient with ESCC,3from patients with HNSCC and 2 from patients without *** 183 samples(96.8%)GAPDH,G3PDH and/orβ-globin were amplified,thus indicating the adequacy of the DNA in those *** DNA was negative in all the 183 samples tested:52 with ESCC,9 with esophagitis and 122 with normal esophageal ***:There was no evidence of HP

关键词： Esophageal cancer Esophageal squamous cell carcinoma Human papillomavirus Head and neck cancer Polymerase chain reactions Nested-polymerase chain reaction

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Modeling uncertainties of reservoir flushing simulations

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International Journal of Sediment Research 2023年第5期38卷 698-710页

作者： Camila Bergmann Goulart Tobias Bleninger Hugo de Oliveira fagundes Fernando Mainardi Fan Department of Environmental Engineering Federal University of Parana Institute of Hydraulic Research Federal University of Rio Grande do Sul

Every dam or barrage construction affects the watercourse and the retention of sediment that previously was carried by the river, which can lead to siltation of the reservoir and obstruction of water intakes over time, reducing their capacities. However, the information available regarding the effect of sediment and drawdown parameters, sediment management at reservoirs, as well as different equational approaches,is scarce. The current research aims to evaluate the effect of parameters associated with numerical modeling of sediment management in reservoirs considering scenarios with different drawdowns,transport equations, sediment size distributions, and thickness of the initial sediment layer. The case study of the Aimore s Hydropower Plant(HPP) is used, applying the Delft3D-FLOW model for twodimensional modeling. All parameters influenced the volume of mobilized sediment, among which the initial layer thickness was the parameter that resulted in the greatest changes in simulated results. In general, the results show that the uncertainties in the input parameters outweigh the uncertainties between the techniques, which found large variations in results when evaluating the use of different transport equations. These results indicate the importance of proper estimation of model parameters for predicting effects with accuracy and the need for such studies before planning and management operations are evaluated to avoid environmental harm and energy waste.

关键词： Reservoir sedimentation Sediment transport modeling Flushing Sediment management

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Thermal and photoperiodic requirements of the seedling stage of three tropical forest species

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Journal of Forestry Research 2023年第1期34卷 209-220页

作者： Fabrina Bolzan martins Mábele de Cássia Ferreira Flávia Fernanda Azevedo fagundes Gabriel Wilson Lorena Florêncio Natural Resource Institute Federal University of ItajubáItajubáMinas Gerais 37500-903Brazil

Air temperature and photoperiod play an important role in the seedling development for tropical forest *** variables are sensitive to climate,and so evaluating thermal and photoperiodic effects on seedling development is fundamental,especially for climate change *** to quantify thermal time and the energy required for plants to reach a development stage include air temperature and cardinal *** photoperiod will also affect physiological reactions of a plant and thus its *** we evaluated the six thermal time methods widely used to compute thermal requirement,and identified the influence of the photoperiod from the 2015 and2016 growing seasons and 12 sowing dates in Itajubá,Minas Gerais state,Brazil,on seedling development of three native tropical forest species Psidium guajava L.(Myrtaceae),Citharexylum myrianthum Cham.(Verbenaceae),and Bixa orellana L.(Bixaceae).The method used to quantify thermal time influenced the analytical results of seedling development;the one that considered three cardinal temperatures and compared them with the mean air temperature(Method5)performed better in computing thermal *** influence of photoperiod on seedling development was inconclusive for the three species,but all three developed better in mild temperatures(between 13.3℃and 26.9℃)with a photoperiod shorter than 13 h.

关键词： Phyllochron Thermal time day length Seedling stage Phenology

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Hydrological variability and long-term floristic-structural modifications in different habitats of a tropical semi-deciduous forest

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Journal of Forestry Research 2022年第3期33卷 801-811页

作者： Alisson Borges Miranda Santos Vinicius Andrade Maia Cléber Rodrigo de Souza Natália de Aguiar-Campos Aurélio de Jesus Rodrigues Pais Wilder Bento da Silva Nathalle Cristine Alencar fagundes Jean daniel Morel Rubens Manoel dos Santos Department of Forestry Sciences Federal University of LavrasCampus UniversitárioC.P.3037LavrasBrazil Faculty of Environmental Engineering and Natural Resources Zambeze UniversityChimoioC.P.2400Mozambique Biological Sciences Universidade do Estado de Minas GeraisUnidade ItuiutabaAv.Antônio Carlos 6627Ituiutaba31270-901Brazil Department of Biology Federal University of LavrasUniversity campusC.P.3037Lavras37200-000Brazil

Shifts in hydrological regimes alter river flow rates and flood pulses, decrease environmental heterogeneity and the floristic-structural complexity of associated plant communities. We tested the hypothesis that drought events affect plant community composition and structure at a small-scale within a riparian fragment towards a reduction in floristic-structural complexity. The tree community was sampled in three habitats (wet, transitional and dry) and monitored in seven inventories carried out between 1991 and 2018. Hydrological variations were evaluated through annual rainfalls, river flow rates and water level data. The species richness and the detrended correspondence analysis axes were used to characterise the temporal modifications in floristic composition. Community structure was described in terms of biomass: accumulated, growth of survivors, mortality and recruitment. Generalised linear mixed models were fitted to evaluate the effects of time and environment in community. It was concluded that the climate has become drier in recent years due to declining precipitation that has affected flow rates and water levels. The floristic-structural complexity of the study fragment was maintained during the monitoring period. However, prolonged and extreme drought events displayed the potential to impact floristic-structural patterns.

关键词： Forest dynamics Climate changes Semi-deciduous seasonal forest Temporal change Functioning communities

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Neumann Boundary Conditions Inhibiting SSB in Coleman-Weinberg Mechanism

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Communications in Theoretical Physics 2010年第12期54卷 1071-1074页

作者： F.N.fagundes R.O.Francisco B.B.Dilem J.A.Nogueira Universidade Federal do Espírito Santo

In this work we show that homogeneous Neumann boundary conditions inhibit the Coleman-Weinberg mechanism for spontaneous symmetry breaking in the scalar electrodynamics if the length of the finite region is small enou... 详细信息

关键词： scalar electrodynamics Neumann boundary conditions spontaneous symmetry breaking

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Estimation of dusk time F-region electron density vertical profiles using LSTM neural networks:A preliminary investigation

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Artificial Intelligence in Geosciences 2023年第1期4卷 209-219页

作者： Lucas Alves Salles Paulo Renato Pereira Silva Guilherme Schwinn fagundes Jonas Sousasantos Alison Moraes Instituto Tecnol´ogico de Aeron´autica-ITA Sao Jos´e Dos CamposBrazil William B.Hanson Center for Space Sciences University of Texas at Dallas-UT DallasRichardsonTXUSA Instituto de Aeron´autica e Espaço-IAE S˜ao Jos´e Dos CamposSP12228-904Brazil

The vertical profile of the ionosphere density plays a significant role in the development of low-latitude Equatorial Plasma Bubbles(EPBs),that in turn lead to ionospheric scintillation which can severely degrade precision and availability of critical users of the Global Navigation Satellite System(GNSS).Accurate estimation of ionospheric delays through vertical electron density profiles is vital for mitigating GNSS errors and enhancing location-based *** objective of this study is to propose a neural network,trained with radio occultation data from the COSMIC-1 mission,that generates average ionospheric electron density profiles during dusk,focusing on the pre-reversal enhancement of the zonal electric *** show that the estimated profiles exhibit a clear seasonal pattern,and reproduce adequately the climatological behavior of the ionosphere,thus presenting strong appeal on ionospheric error attenuation.

关键词： Ionosphere density Equatorial plasma bubbles(EPBs) Ionospheric scintillation Global navigation satellite system(GNSS) Neural network modeling

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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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阿塞洛米塔尔图巴朗钢铁集团火花发射光谱法优化氮的分析

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冶金分析 2012年第7期32卷 25-31页

作者： fagundes Laura DIEGUEZ Ana Carolina 阿塞洛米塔尔图巴朗钢铁集团

近年来,钢铁行业需求量快速上升,竞争也变得更加激烈。为了得到性能可靠的产品,钢铁车间在生产工艺方面需要进一步严格控制好产品的生产规格。在这种背景下,为了严格控制好生产工艺的密封性并保证产品所期望的特性(尤其是其韧性和机械... 详细信息

近年来,钢铁行业需求量快速上升,竞争也变得更加激烈。为了得到性能可靠的产品,钢铁车间在生产工艺方面需要进一步严格控制好产品的生产规格。在这种背景下,为了严格控制好生产工艺的密封性并保证产品所期望的特性(尤其是其韧性和机械加工性方面),精确地进行氮的分析必不可少。在过去几年中,经典燃烧技术(CC)已广泛应用于鉴定钢中的碳、硫和氮元素。而火花发射法因其性能改进、耗材成本(燃烧技术方面)降低以及在分析时间缩短等方面的优势,也在氮分析方面得到了应用,并且应用越来越广泛。本项研究的目的在于通过火花发射光谱仪(OES)对氮分析进行优化。研究是在巴西塞拉的阿塞洛米塔尔图巴朗钢铁集团的化学分析实验室进行,利用DMAIC方法学(一种用于改进生产工艺质量的研究方法)[1],对潜在的影响因素(包括漂移、样品和周期)进行了分析,并确定和优化了影响氮分析精度的根本原因。在实施该计划后,对结果的精度(基于内标物的标准偏差)和准确性(通过与OE认证的参考物质和力可交叉核验结果进行比较)进行了评估。在本研究项目之前,通过光发射法测得的氮元素的标准偏差高达0.004 0%。阿塞洛米塔尔图巴朗钢铁集团利用光谱仪完成所有的研究计划后,试验表明,其测定标准偏差低达0.000 5%,充分展现了该技术的潜力。本研究对这一标准偏差进行了监测,频率为每周一次,监测期为3个月。结果发现,该标准偏差在0.000 3%到0.000 5%之间波动,表明稳定性较好。由此可见,火花发射光谱技术是氮分析的一种较有前途的方法。

关键词：光发射氮分析钢铁经典燃烧

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Stepped machine learning for the development of mineral models: Concepts and applications in the pre-salt reservoir carbonate rocks

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Energy and AI 2021年第1期3卷 167-179页

作者： Lucas Abreu Blanes de Oliveira Luiz Felipe Niedermaier Custodio Thais Bortotti fagundes Carina Ulsen Cleyton de Carvalho Carneiro Petrobras–Petroleo Brasileiro S.A. Avenida Henrique Valadares 28CentroRio de Janeiro20231-030 Rio de JaneiroBrazil Universidade de Sao Paulo USPEscola PolitecnicaPraça Narciso de AndradeVila MathiasSantosSão Paulo 11013-560Brazil

Understanding rock mineralogy is essential for formation evaluation,improving the calculation of porosity and hydrocarbon *** primary method to obtain the mineralogy from a well is by applying a model to the geochemical tool’s chemical ***,creating a mineralogical model presents challenges such as the minerals’chemical composition and the decision to include a mineral in the *** traditional application of machine learning can make mineral models less realistic since conventional training is developed based on a set of minerals with different occurrences,lowering some minerals’*** present research proposes the stepped machine learning(SML),a stepped way to use machine learning to create a mineralogical model from chemical and mineralogical data.A database was assembled with the elemental concentration obtained with XRF analyses and the mineral concentrations obtained with XRD *** chemical elements were Al,Ca,Fe,K,Mg,Mn,Na,Si,and *** minerals were calcite,dolomite,quartz,clays,K-feldspar,plagioclase,and *** algorithms were tested:MLP,GAN,Random Forest,and XGBoost,with XGBoost showing the best *** was applied,where a mineral model results are used to train a subsequent *** allowed for a significant improvement in some models,notably to clays with an increase in R 2 from 0.597 to 0.853,quartz an increase from 0.673 to 0.869,and calcite,from 0.758 to 0.862.A decrease in the mean squared error of these minerals’models was also *** model was applied to the geochemical logs from three wells drilled in the Brazilian pre-salt,and the results were compared with XRD *** SML model was able to honor the mineral concentrations for different *** is demonstrated that the integration between machine learning tools and geological knowledge in SML was crucial for creating a representative mineralogical model.

关键词： minerals quartz reservoir

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