Cd-tolerance markers of Pfaffia glomerata (Spreng.) Pedersen plants: Anatomical and physiological features

Physiological and anatomical features of Cd-tolerance in Pfaffia glomerata were examined by exposing plantlets to nutrient solutions with increasing Cd concentrations (0, 15, 45, and 90 μmol Cd L-1), and possible Cd-tolerance markers were established. Cd contents were found to be higher in roots than in shoots. According to the bio-concentration factor data, this species is effectively a Cd-hyperaccumulator, as previously attested. Cd induced the appearance of xeromorphic characteristics in leaves (decreased water potential, increased numbers and decreased stomata size) and increased root endodermis thickness. The enzymatic antioxidant systems of roots and leaves were differently affected by Cd. The coordinated activities of antioxidant enzymes were effective in reducing Cd-induced reactive oxygen species in plants, mainly in leaves. Root endodermis thickness, stomatal size and numbers, root superoxide dismutase, and guaiacol peroxidase, as well as leaf guaiacol peroxidase and catalase activities can all be considered Cd-tolerance markers in Pfaffia glomerata. Due to its high root Cd accumulation, Pfaffia glomerata may be useful in Cd-phytoextraction programs, however the pharmacological use of plants grown in the presence of Cd must be avoided

Estimativa do IAF de cafeeiro a partir do volume de folhas e arquitetura da planta

The methods used for estimating the leaf area index (LAI) of coffee (Coffea arabica L.) show limitations related to therepresentation of some aspects of coffee crops, affecting the LAI in time and space. This work was developed to propose a method forassessing the LAI of coffee aiming to reduce those limitations. We studied plants in the production phase of the Mundo Novo and Catuaívarieties, in plantations located in Lavras-MG, during the dry season and rainy season from 2010 to 2011. The height, total length ofprimary branches, the length of the region without leaves in the canopy and the LAI of those plants were evaluated. These data wereused to estimate the volume occupied by leaves and, subsequently, to obtain equations that describe the behavior of LAI in relation tothis volume. There were three equations that described the LAI variations in relation to the volume occupied by leaves: linear,expolinear and seasonal. These three models showed realistic estimates when applied to plants from plantations located in TrêsPontas-MG. Potentially, this method can be applied for estimating the LAI of a plant or canopies. It has the advantage of a morerealistic representation of the shape of the plant in time and space compared to similar methods. With the proposed method is expectedto meet the demands of productivity forecasting models for coffee, reducing the limitations observed in the commonly used methods forLAI determination.Os métodos de estimativa do índice de área foliar (IAF) utilizados para cafeeiros (Coffea arabica L.) apresentamlimitações relacionadas à representação de particularidades da cultura que afetam o IAF no tempo e no espaço. Desenvolveuseeste trabalho objetivando propor um método de estimativa do IAF de forma a reduzir essas limitações. Foram utilizadoscafeeiros em fase produtiva, de cultivos da região de Lavras-MG, das variedades Mundo Novo e Catuaí, coletados durantea estação seca e a estação chuvosa de 2010 a 2011. Nessas plantas avaliou-se a altura a partir do nível do solo, comprimentototal de ramos plagiotrópicos, o comprimento da região sem folhas na copa e o IAF. Esses dados foram utilizados paraestimar o volume de folhas das plantas e, posteriormente, para a obtenção de equações que descrevem o comportamento doIAF em função do volume de folhas. Verificaram-se três ajustes das variações de IAF em função do volume de folhas:comportamento linear, expolinear e sazonal. Os três modelos apresentaram estimativas realistas, quando aplicados emcafeeiros do município de Três Pontas-MG. Potencialmente, os modelos podem ser aplicados na estimativa do IAF de umaplanta isolada ou para parcelas homogêneas. Possuem a vantagem de uma representação mais realista da forma da planta notempo e no espaço em comparação com métodos semelhantes. Com o método proposto, espera-se atender demandas demodelos de previsão de produtividade de cafeeiros, reduzindo as limitações observadas nos métodos comumente utilizadospara a determinação do IAF

Convergence in relationships between leaf traits, spectra and age across diverse canopy environments and two contrasting tropical forests

• Leaf age structures the phenology and development of plants, as well as the evolution of leaf traits over life histories. However, a general method for efficiently estimating leaf age across forests and canopy environments is lacking. • Here, we explored the potential for a statistical model, previously developed for Peruvian sunlit leaves, to consistently predict leaf ages from leaf reflectance spectra across two contrasting forests in Peru and Brazil and across diverse canopy environments. • The model performed well for independent Brazilian sunlit and shade canopy leaves (R2 = 0.75–0.78), suggesting that canopy leaves (and their associated spectra) follow constrained developmental trajectories even in contrasting forests. The model did not perform as well for mid-canopy and understory leaves (R2 = 0.27–0.29), because leaves in different environments have distinct traits and trait developmental trajectories. When we accounted for distinct environment–trait linkages – either by explicitly including traits and environments in the model, or, even better, by re-parameterizing the spectra-only model to implicitly capture distinct trait-trajectories in different environments – we achieved a more general model that well-predicted leaf age across forests and environments (R2 = 0.79). • Fundamental rules, linked to leaf environments, constrain the development of leaf traits and allow for general prediction of leaf age from spectra across species, sites and canopy environments

Highly reactive light-dependent monoterpenes in the Amazon

Despite orders of magnitude difference in atmospheric reactivity and great diversity in biological functioning, little is known about monoterpene speciation in tropical forests. Here we report vertically resolved ambient air mixing ratios for 12 monoterpenes in a central Amazon rainforest including observations of the highly reactive cis-β-ocimene (160 ppt), trans-β-ocimene (79 ppt), and terpinolene (32 ppt) which accounted for an estimated 21% of total monoterpene composition yet 55% of the upper canopy monoterpene ozonolysis rate. All 12 monoterpenes showed a mixing ratio peak in the upper canopy, with three demonstrating subcanopy peaks in 7 of 11 profiles. Leaf level emissions of highly reactive monoterpenes accounted for up to 1.9% of photosynthesis confirming light-dependent emissions across several Amazon tree genera. These results suggest that highly reactive monoterpenes play important antioxidant roles during photosynthesis in plants and serve as near-canopy sources of secondary organic aerosol precursors through atmospheric photooxidation via ozonolysis. © 2015. The Authors

Diel and seasonal changes of biogenic volatile organic compounds within and above an Amazonian rainforest

The Amazonian rainforest is a large tropical ecosystem, which is one of the last pristine continental terrains. This ecosystem is ideally located for the study of diel and seasonal behaviour of biogenic volatile organic compounds (BVOCs) in the absence of local human interference. In this study, we report the first atmospheric BVOC measurements at the Amazonian Tall Tower Observatory (ATTO) site, located in central Amazonia. A quadrupole proton-transfer-reaction mass spectrometer (PTR-MS), with seven ambient air inlets, positioned from near ground to about 80 m (0.05, 0.5, 4, 24, 38, 53 and 79 m above the forest floor), was deployed for BVOC monitoring. We report diel and seasonal (February-March 2013 as wet season and September 2013 as dry season) ambient mixing ratios for isoprene, monoterpenes, isoprene oxidation products, acetaldehyde, acetone, methyl ethyl ketone (MEK), methanol and acetonitrile. Clear diel and seasonal patterns were observed for all compounds. In general, lower mixing ratios were observed during night, while maximum mixing ratios were observed during the wet season (February-March 2013), with the peak in solar irradiation at 12:00 LT (local time) and during the dry season (September 2013) with the peak in temperature at 16:00 LT. Isoprene and monoterpene mixing ratios were the highest within the canopy with a median of 7.6 and 1 ppb, respectively (interquartile range (IQR) of 6.1 and 0.38 ppb) during the dry season (at 24 m, from 12:00 to 15:00 LT). The increased contribution of oxygenated volatile organic compounds (OVOCs) above the canopy indicated a transition from dominating forest emissions during the wet season (when mixing ratios were higher than within the canopy), to a blend of biogenic emission, photochemical production and advection during the dry season when mixing ratios were higher above the canopy. Our observations suggest strong seasonal interactions between environmental (insolation, temperature) and biological (phenology) drivers of leaf BVOC emissions and atmospheric chemistry. Considerable differences in the magnitude of BVOC mixing ratios, as compared to other reports of Amazonian BVOC, demonstrate the need for long-term observations at different sites and more standardized measurement procedures, in order to better characterize the natural exchange of BVOCs between the Amazonian rainforest and the atmosphere. © Author(s) 2015

The CO2 record at the Amazon Tall Tower Observatory : A new opportunity to study processes on seasonal and inter-annual scales

High-quality atmospheric CO2 measurements are sparse in Amazonia, but can provide critical insights into the spatial and temporal variability of sources and sinks of CO2. In this study, we present the first 6 years (2014-2019) of continuous, high-precision measurements of atmospheric CO2 at the Amazon Tall Tower Observatory (ATTO, 2.1 degrees S, 58.9 degrees W). After subtracting the simulated background concentrations from our observational record, we define a CO2 regional signal (Delta CO2obs) that has a marked seasonal cycle with an amplitude of about 4 ppm. At both seasonal and inter-annual scales, we find differences in phase between Delta CO2obs and the local eddy covariance net ecosystem exchange (EC-NEE), which is interpreted as an indicator of a decoupling between local and non-local drivers of Delta CO2obs. In addition, we present how the 2015-2016 El Nino-induced drought was captured by our atmospheric record as a positive 2 sigma anomaly in both the wet and dry season of 2016. Furthermore, we analyzed the observed seasonal cycle and inter-annual variability of Delta CO2obs together with net ecosystem exchange (NEE) using a suite of modeled flux products representing biospheric and aquatic CO2 exchange. We use both non-optimized and optimized (i.e., resulting from atmospheric inverse modeling) NEE fluxes as input in an atmospheric transport model (STILT). The observed shape and amplitude of the seasonal cycle was captured neither by the simulations using the optimized fluxes nor by those using the diagnostic Vegetation and Photosynthesis Respiration Model (VPRM). We show that including the contribution of CO2 from river evasion improves the simulated shape (not the magnitude) of the seasonal cycle when using a data-driven non-optimized NEE product (FLUXCOM). The simulated contribution from river evasion was found to be 25% of the seasonal cycle amplitude. Our study demonstrates the importance of the ATTO record to better understand the Amazon carbon cycle at various spatial and temporal scales.Peer reviewe

The CO2 record at the Amazon Tall Tower Observatory: A new opportunity to study processes on seasonal and inter-annual scales

Abstract High-quality atmospheric CO2 measurements are sparse in Amazonia, but can provide critical insights into the spatial and temporal variability of sources and sinks of CO2. In this study, we present the first 6 years (2014?2019) of continuous, high-precision measurements of atmospheric CO2 at the Amazon Tall Tower Observatory (ATTO, 2.1°S, 58.9°W). After subtracting the simulated background concentrations from our observational record, we define a CO2 regional signal () that has a marked seasonal cycle with an amplitude of about 4 ppm. At both seasonal and inter-annual scales, we find differences in phase between and the local eddy covariance net ecosystem exchange (EC-NEE), which is interpreted as an indicator of a decoupling between local and non-local drivers of . In addition, we present how the 2015?2016 El Niño-induced drought was captured by our atmospheric record as a positive 2σ anomaly in both the wet and dry season of 2016. Furthermore, we analyzed the observed seasonal cycle and inter-annual variability of together with net ecosystem exchange (NEE) using a suite of modeled flux products representing biospheric and aquatic CO2 exchange. We use both non-optimized and optimized (i.e., resulting from atmospheric inverse modeling) NEE fluxes as input in an atmospheric transport model (STILT). The observed shape and amplitude of the seasonal cycle was captured neither by the simulations using the optimized fluxes nor by those using the diagnostic Vegetation and Photosynthesis Respiration Model (VPRM). We show that including the contribution of CO2 from river evasion improves the simulated shape (not the magnitude) of the seasonal cycle when using a data-driven non-optimized NEE product (FLUXCOM). The simulated contribution from river evasion was found to be 25% of the seasonal cycle amplitude. Our study demonstrates the importance of the ATTO record to better understand the Amazon carbon cycle at various spatial and temporal scales

Intra- and interannual changes in isoprene emission from central Amazonia

Isoprene emissions are a key component in biosphere-atmosphere interactions, and the most significant global source is the Amazon rainforest. However, intra- and interannual variations in biological and environmental factors that regulate isoprene emission from Amazonia are not well understood and, thereby, are poorly represented in models. Here, with datasets covering several years of measurements at the Amazon Tall Tower Observatory (ATTO) in central Amazonia, Brazil, we (1) quantified canopy profiles of isoprene mixing ratios across seasons of normal and anomalous years and related them to the main drivers of isoprene emission - solar radiation, temperature, and leaf phenology; (2) evaluated the effect of leaf age on the magnitude of the isoprene emission factor (Es) from different tree species and scaled up to canopy with intra- and interannual leaf age distribution derived by a phenocam; and (3) adapted the leaf age algorithm from the Model of Emissions of Gases and Aerosols from Nature (MEGAN) with observed changes in Es across leaf ages. Our results showed that the variability in isoprene mixing ratios was higher between seasons (max during the dry-to-wet transition seasons) than between years, with values from the extreme 2015 El Niño year not significantly higher than in normal years. In addition, model runs considering in situ observations of canopy Es and the modification on the leaf age algorithm with leaf-level observations of Es presented considerable improvements in the simulated isoprene flux. This shows that MEGAN estimates of isoprene emission can be improved when biological processes are mechanistically incorporated into the model.This research was supported by the German Federal Ministry of Education and Research, BMBF funds 01LB1001A; Brazilian Ministry of Science, Technology, Innovation and Communication; FINEP/MCTIC contract 01.11.01248.00); UEA; FAPEAM; LBA/INPA; and SDS/CEUC/RDS-Uatumã. It was also supported by grant nos. NSF-PRFB-1711997 and NSF-1754163. The article processing charges for this open-access publication were covered by the Max Planck Society.Peer reviewe

A estratificação e o manejo adequado da dor: Stratification and proper pain management

A dor é um potencial de risco para a saúde pública, esta se caracteriza pela experiência multidimensional associada a aspectos físicos e emocionais. A dor alerta o perigo e evita danos orgânicos, mas quando está impossibilita atividades diárias e impacta a qualidade de vida do paciente é classificada como patológica e urge por interferência médica. O seguinte artigo objetivou descrever através da revisão narrativa de literatura os aspectos referentes da dor e o seu manejo adequado. A dor é um amplo complexo que possui a classificação conforme a localização, tipo, intensidade, periodicidade. As categorias referentes a dor são nociceptivas, neuropática, psicogênica. Ademais, as síndromes dolorosas são diversas e podem acometer qualquer sistema do corpo. Ressaltando ser essencial a categorização do máximo possível de informações para conduzir adequadamente ao tratamento destas enfermidades.&nbsp