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Mango cultivation in a protected environment is becoming widespread in the Mediterranean basin where the species has to face unfavorable weather conditions which do not occur in its native cultivation areas. Besides open-air cultivation, greenhouses—and other protection systems such as shading nets and partial covering of plastic films—have been tested recently. In this study, we focused on assessing the effect of a shading net, and a partially covering plastic film, on the development of “Kensington Pride” mango fruit skin-color, its final quality, and the plants’ photosynthetic activity. A new method of measuring mango skin-color on different sides of the fruit is proposed. No difference was observed with regard to the observed parameters between the plants cultivated under the two different protection systems and those growing in the open air. It can, therefore, be stated that such cultivation techniques do not alter the development of the mango fruit and its appearance, nor the plant’s photosynthetic activity.

Salvia ceratophylloides (Ard.) is an endemic and rare plant species recently rediscovered as very few individuals at two different Southern Italy sites. The study of within-plant variation is fundamental to understand the plant adaptation to the local conditions, especially in rare species, and consequently to preserve plant biodiversity. Here, we reported the variation of the morpho-ecophysiological and metabolic traits between the sessile and petiolate leaf of S. ceratophylloides plants at two different sites for understanding the adaptation strategies for surviving in these habitats. The S. ceratophylloides individuals exhibited different net photosynthetic rate, maximum quantum yield, light intensity for the saturation of the photosynthetic machinery, stomatal conductance, transpiration rate, leaf area, fractal dimension, and some volatile organic compounds (VOCs) between the different leaf types. This within-plant morpho-physiological and metabolic variation was dependent on the site. These results provide empirical evidence of sharply within-plant variation of the morpho-physiological traits and VOCs profiles in S. ceratophylloides, explaining the adaptation to the local conditions.

This study aimed to evaluate the growth and physiology of Annona squamosa seedlings under increasing irrigation depths and phosphorus doses. The experiment was conducted in protected environment, evaluating five irrigation depths and four P2O5- doses, arranged in 5 x 4 factorial scheme, in randomized blocks, with four replicates and one plant per plot. Treatments were irrigation depths of 60, 80, 100, 120 and 140% of the real evapotranspiration of the seedlings – ETr and phosphorus doses of 0, 350, 700 and 1050 mg dm-3 of P2O5-. Plants were evaluated at 120 days after transplanting with respect to growth, gas exchanges, leaf water potential and total dry matter accumulation. Phosphorus dose of 350 mg dm-3 promotes satisfactory dry matter accumulation for A. squamosa seedlings, especially under 100% ETr irrigation. Leaf water potential and gas exchanges of A. squamosa are affected by water stress, through both lack and excess of water. Stomatal conductance is the variable most sensitive to the lack of water, whereas photosynthesis and water use efficiency are the most sensitive to the excess of water. Irrigation depth of 100% ETr is ideal to produce A. squamosa seedlings, but the irrigation depth of 80% ETr can be used to produce these seedlings, disregarding small losses of growth. Objetivou-se avaliar o crescimento e a fisiologia de mudas de A. squamosa sob lâminas crescentes de irrigação e doses de fósforo. O experimento foi conduzido em ambiente protegido, avaliando cinco lâminas de irrigação e quatro doses P2O5, arranjados em esquema fatorial 5 x 4, em blocos casualizados, com quatro repetições e uma planta por parcela. Os tratamentos das lâminas foram 60, 80, 100, 120 e 140% da evapotranspiração real das mudas – ETr e as quatro doses de fósforo 0, 350, 700 e 1050 mg dm-3 de P2O5. As plantas foram avaliadas aos 120 dias após o transplantio, quanto ao crescimento, trocas gasosas, potencial hídrico foliar e acúmulo de matéria seca total. A dose de fósforo de 350 mg dm-3 proporciona acúmulo de matéria seca satisfatório para as mudas de A. squamosa, principalmente sob irrigação com 100% da ETr. O potencial hídrico foliar e as trocas gasosas da A. squamosa são afetadas pelo estresse hídrico, tanto por falta como por excesso de água, sendo a condutância estomática a variável mais sensível a falta de água e a fotossíntese e eficiência do uso da água as mais sensíveis ao excesso de água. A lâmina de 100% da ETr é a ideal para a produção de mudas de A. squamosa, porém a lamina de 80% da ETr pode ser utilizada para a produção de mudas de A. squamosa, admitindo-se pequenas perdas no crescimento.

Rising temperatures in most viticultural regions are associated with a higher incidence of drastic weather circumstances such as heatwaves. The consequences are reflected in qualitative and quantitative white grapes characteristics. In fact, there is an enhancement in alcohol content and a jeopardized reduction in the aromatic potential. We performed a scientific test to assuage the bump of heatwaves and exposure of grapes on Vitis vinifera cv. “Sauvignon Blanc” with exposed vines (untreated) or with kaolin foliar treatment or with partial fruit-zone shading (shading net 30 and 70%). This work aimed to evaluate the effects of shading net (SD-30% and SD-70%) and foliar kaolin (K) treatment on physiology, technological maturity, and thiolic precursors in Italy during the 2020–2021 seasons. For this purpose, four treatments were established: SD-30% (green artificial shading net at 30%), SD-70% (green artificial shading net at 70%), K (foliar kaolin), and CTRL (no application). During the two vintages, single-leaf gas exchange appraisal, leaf temperature, berry temperature, chlorophyll fluorescence, pre-dawn, and leaf water potential were measured. Moreover, berry weight, pH, °Brix, acidity (technological maturity specifications), and the following thiolic precursors were analyzed: 3-S-glutathionylhexan-1-ol (Glut-3MH), S-4-(4-methylpentan-2-one)-L-cysteine (Cys-4MMP), and 3-S-cysteinylhexan-1-ol (Cys-3MH). SD-70% and K denoted less negative water potential, a lower berry temperature, and a higher level of all precursors than the other treatments. Acidity and sugar parameters indicated significant differences among treatments. The lower berry weight and the lower tartaric acidity were found in the CTRL treatment. In comparison, SD-70% and K showed lower and more balanced sugar contents. As a result of global warming, color shading net and kaolin have been demonstrated to be good practices to counterpoise the divergence between aromatic and technological maturity in Sauvignon Blanc grapevines.

The COVID-19 pandemic changed the management of emergency medicine and those complications that needed interventional procedures, such as endoscopy or other radiological procedures. At the beginning of the outbreak, there were no exploitable recommendations regarding the proper policy to apply for limiting the virus spread during endoscopy. Between the first and the second wave, the approach regarding interventional procedures changed, due to higher awareness and newly defined protocols, even if different among the health centers. Patients with severe COVID-19 may develop major gastrointestinal complications or require nutritional support, so interventional procedures are required at bedside, even if patients are in isolated rooms. Our tertiary center admitted 95 patients with severe COVID-19 at our ICU-dedicated department until May 2021, and 56% of them died. Among them, 61 endoscopic procedures were performed, mainly gastroscopies (81.96%) followed by colonoscopies (11.47%) and other more advanced procedures (6.55%). Our approach aimed to adapt and create COVID-related protocols, dedicated itineraries, and rooms in a separate department with the prospect to easily organize complete and safe endoscopic theaters at the COVID-ICU department.

beta-1,3-glucans such as paramylon act as elicitors in plants, modifying the hormonal levels and the physiological responses. Plant hormones affect all phases of the plant life cycle and their responses to environmental stresses, both biotic and abiotic. The aim of this study was to investigate the effects of a root treatment with Euglena gracilis paramylon on xylem hormonal levels, photosynthetic performance and dehydration stress in tomato (Solanum lycopersicum L.). Paramylon granules were processed to obtain the linear fibrous structures capable to interact with tomato cell membrane. Modulation of hormone levels (abscisic acid, jasmonic acid and salicylic acid) and related physiological responses such as CO2 assimilation rate, stomatal and mesophyll conductance, intercellular CO2 concentration, transpiration rate, water-use efficiency, quantum yield of photosystem II and leaf water potential were investigated. The results indicate a clear dose-dependent effect of paramylon on the hormonal content of xylem sap, photosynthetic performance and dehydration tolerance. Paramylon has the capability to enhance plant defence capacity against abiotic stress, such as drought, by modulating the conductance to CO2 diffusion from air to the carboxylation sites and improving the water-use efficiency.

Made available in DSpace on 2021-06-25T10:16:23Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-01-01 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) To meet the growing demand for soybean it is necessary to increase crop yield, even in low water availability conditions. To circumvent the negative effects of water deficit, application of biostimulants with anti-stress effect has been adopted, including products based on fulvic acids and Ascophyllum nodosum (L.) seaweed extracts. In this study, we determined which formulation and dosage of a biostimulant is more efficient in promoting the recovery of soybean plants after stress due to water deficit. The experiment was conducted in a greenhouse, in a double-factorial randomized block design with two additional factors, four repetitions and eleven treatments consisting of three biostimulant formulations (F1, F2 and F3), and three dosages (0.25; 0.50 and 1.0 kg ha−1); a control with water deficit and a control without water deficit. Soybean plants were kept at 50% of the pot's water capacity for three days, then rehydrated and submitted to the application of treatments with biostimulant. After two days of recovery, growth, physiological, biochemical and yield parameters were evaluated. All plants that received the application of the biostimulant produced more than the water-stressed control plants. The biostimulant provided higher photosynthetic rates, more efficient mechanisms for dissipating excess energy and higher activities of antioxidant enzymes. Plants treated with biostimulant were more efficient in the recovery of the metabolic activities after rewatering, resulting in increased soybean tolerance to water deficit and reduced yield losses. The best result obtained was through the application of formulation 2 of the biostimulant at a dosage of 0.25 kg ha−1. Laboratory of Ecophysiology Applied to Agriculture School of Agricultural Sciences São Paulo State University (UNESP) Laboratory of Ecophysiology and Crop Production Federal Goianian Institute (IF Goiano), Campus Rio Verde Fertilizers Heringer Laboratory of Ecophysiology Applied to Agriculture School of Agricultural Sciences São Paulo State University (UNESP)

Selection and improvement of crops subjected to salinity constitutes an urgent need for increasing agricultural and food production in order to feed the growing human population. The aim of the present study is to evaluate the role of salicylic acid (SA) application in mitigating the adverse effects of salinity on faba bean (Vicia faba L.) at the physiological and molecular levels. Fort this purpose, two faba bean genotypes were subjected to various concentrations of NaCl and salicylic acid in a full factorial design. After that, growth, water status, gas exchanges, photosynthesis parameters, ions homeostasis and antioxidant enzymes activities were evaluated. The obtained results demonstrated that salinity induced several limitations in plants growth and physiological attributes. In response, salt stressed faba bean plants improved water status and enhanced antioxidant enzymatic activities. Remarkably, salt-tolerance of both genotypes was significantly improved by salicylic acid application which allowed the maintenance of cell membrane and photosynthetic process, restoring of ion homeostasis and the diminution of oxidative damages. Overall, the difference between genotypes is rather quantitative than qualitative even if the genotype Aguadulce displayed better growth, physiological and molecular response under salt stress than the genotype Histal. Besides, the beneficial effects of salicylic acid vary according to its concentration, the tested genotype and the studied parameter; the genotype Aguadulce performs better under the treatment with 0.5 mM SA while the genotype Histal manifests greater behaviour under the treatment with 1 mM SA. Therefore, salicylic acid can be considered as potential growth regulator to improve the salt response of faba bean. The application of salicylic acid would provide a practical basis for wide cultivation of faba bean in marginal and wastelands under-cultivated and might propose an effective ecological and economical alternative solution to deal with salt-affected soils mainly in arid regions.

Callistemon citrinus and Viburnum lucidum are appreciated and widespread ornamental shrubs for their abundant flowering and/or brilliant foliage. The intrinsic tolerance to drought/salinity supports their use in urban areas and in xeriscaping. Despite adaptive responses of these ornamental species to sodium chloride (NaCl) have been extensively explored, little is known on the effects of other salt solution, yet iso-osmotic, on their growth, mineral composition and metabolism. The present research was aimed to assess responses at the biochemical, physiological and anatomical levels to iso-osmotic salt solutions of NaCl and CaCl2 to discriminate the effects of osmotic stress and ion toxicity. The two ornamental species developed different salt-tolerance mechanisms depending on the salinity sources. The growth parameters and biomass production decreased under salinization in both ornamental species, independently of the type of salt, with a detrimental effect of CaCl2 on C. citrinus. The adaptive mechanisms adopted by the two ornamental species to counteract the NaCl salinity were similar, and the decline in growth was mostly related to stomatal limitations of net CO2 assimilation rate, together with the reduction in leaf chlorophyll content (SPAD index). The stronger reduction of C. citrinus growth compared to V. lucidum, was due to an exacerbated reduction in net photosynthetic rate, driven by both stomatal and non stomatal limitations. In similar conditions, V. lucidum exhibited other additional adaptive response, such as modification in leaf functional anatomical traits, mostly related to the reduction in the stomata size allowing plants a better control of stomata opening than in C. citrinus. However, C. citrinus plants displayed an increased ability to retain higher Cl- levels in leaves than in roots under CaCl2 salinity compared to V. lucidum, thus, indicating a further attempt to counteract chloride toxicity through an increased vacuolar compartmentalization and to take advantages of them as chip osmotica.

The aim of this study was to evaluate the physiological and growth responses of watermelon under application of NPK rates using different proportions of mineral and organic fertilizers. The experiment was taken place in an area located at the Federal University of Campina Grande (UFCG), Campus Pombal - PB (6º48'16'' S and 37º49'15'' W), during the period from June to September 2013. The treatments consisted of three nutrient concentrations of N, P and K (50, 100 and 150% of NPK recommendation for watermelon) and five proportions of mineral and organic fertilizer (100/0, 75/25, 50/50, 25/75 to 0/100). The design was a randomized block in factorial scheme 3 x 5, with four replications. The amount of 100 % was the corresponding NPK 120 kg ha-1, respectively, for N, P and K. They were evaluated: gas exchange, leaf dry matter, stem, fruit and leaf area. The concentration of 150 % of the recommended NPK to the culture of watermelon was the most effective in increasing the physiological characteristics and dry matter accumulation in stem, leaf, fruit, and leaf area. The combined application of mineral and organic fertilizer provides equivalent photosynthetic rate isolated application of mineral fertilizer with an 50/50 ratio the most effective for this variable. The proportions 75/25 and 50/50 were the most efficient in dry matter accumulation in watermelon. El objetivo del trabajo fue evaluar las respuestas fisiológicas y de crecimiento de la sandía mediante la aplicación de dosis de NPK, utilizando diferentes proporciones de fertilizantes minerales y orgánicos. El experimento se realizó en un área ubicada en la Universidad Federal de Campina Grande (UFCG), Campus Pombal - PB (6º48'16''S y 37º49'15 '' O), de junio a septiembre de 2013. Los tratamientos fueron compuesto por tres concentraciones de nutrientes N, P y K (50, 100 y 150% de la recomendación NPK para sandías) y cinco proporciones de fertilizante mineral y orgánico (100/0, 75/25, 50/50, 25/75 y 0/100). El diseño fue en bloques al azar, en un esquema factorial de 3 x 5, con cuatro repeticiones. La cantidad de NPK correspondiente al 100% fue de 120 kg ha-1. Se evaluaron: intercambio gaseoso, materia seca de hojas, tallo y frutos y área foliar. La concentración de 150% de la recomendación NPK para el cultivo de la sandía fue la más eficiente para incrementar las características fisiológicas y en la acumulación de materia seca del tallo, hoja y fruto, y en el área foliar. La aplicación combinada de fertilizante mineral y orgánico proporciona una tasa fotosintética equivalente a la aplicación aislada de fertilizante mineral, siendo la relación 50/50 la más eficiente para esta variable. Las proporciones 75/25 y 50/50 fueron las más eficientes en la acumulación de masa seca en la sandía. O objetivo do trabalho foi avaliar as respostas fisiológicas e de crescimento da melancieira sob aplicação de doses de NPK, utilizando diferentes proporções de adubos minerais e orgânicos. O experimento foi realizado em área localizada na Universidade Federal de Campina Grande (UFCG), Campus Pombal – PB (6º48’16’’S e 37º49’15’’ W), durante o período de junho a setembro de 2013. Os tratamentos foram constituídos de três concentrações dos nutrientes N, P e K (50, 100 e 150 % da recomendação de NPK para melancieira) e cinco proporções de adubo mineral e orgânico (100/0, 75/25, 50/50, 25/75 e 0/100). O delineamento foi em blocos casualizados, no esquema fatorial 3 x 5, com quatro repetições. A quantidade de NPK correspondente a 100% foi de 120 kg ha-1. Foram avaliadas: as trocas gasosas, a matéria seca das folhas, do caule, e dos frutos, e a área foliar. A concentração de 150% da recomendação de NPK para a cultura da melancieira foi a mais eficiente no incremento das características fisiológicas e no acúmulo de matéria seca do caule, da folha, e do fruto, e na área foliar. A aplicação combinada de fertilizante mineral e orgânico proporciona taxa fotossintética equivalente à aplicação isolada de fertilizante mineral, sendo a proporção 50/50 a mais eficiente para essa variável. As proporções 75/25 e 50/50 foram as mais eficientes no acúmulo de massa seca na melancieira.

This study aimed to evaluate the productive characteristics, gas exchange and water use efficiency of the banana 'Prata-Anã' clone Gorutuba under different irrigation intervals associated with different emitter heights. Therefore, a field experiment was conducted in a 2 x 4 factorial scheme: two irrigation intervals (daily and every two days) and four emitter heights (50, 70, 90, and 110 cm) in a completely randomized design with four replicates. The irrigation depths applied by the microsprinkler irrigation system were calculated as a function of crop evapotranspiration. The gas exchanges were evaluated during the period of greatest climatic stress, and the productive characteristics were evaluated at harvest. The economic water use efficiency was determined indirectly by considering the production divided by the applied irrigation depth, which was the same in all the treatments. The instantaneous water use efficiency was estimated with an infrared gas analyzer in the critical climatic period. There was no interaction between the irrigation intervals and emitter heights. The two-day irrigation interval resulted in lower values of leaf temperature and photosynthetically active radiation incident on the leaves, resulting in a higher fruit weight and, consequently, higher yields and a higher water use efficiency. The highest fruit weights were obtained at heights of 70 and 90 cm.

Callistemon citrinus and Viburnum lucidum are appreciated and widespread ornamental shrubs for their abundant flowering and/or brilliant foliage. The intrinsic tolerance to drought/salinity supports their use in urban areas and in xeriscaping. Despite adaptive responses of these ornamental species to sodium chloride (NaCl) have been extensively explored, little is known on the effects of other salt solution, yet iso-osmotic, on their growth, mineral composition and metabolism. The present research was aimed to assess responses at the biochemical, physiological and anatomical levels to iso-osmotic salt solutions of NaCl and CaCl2 to discriminate the effects of osmotic stress and ion toxicity. The two ornamental species developed different salt-tolerance mechanisms depending on the salinity sources. The growth parameters and biomass production decreased under salinization in both ornamental species, independently of the type of salt, with a detrimental effect of CaCl2 on C. citrinus. The adaptive mechanisms adopted by the two ornamental species to counteract the NaCl salinity were similar, and the decline in growth was mostly related to stomatal limitations of net CO2 assimilation rate, together with the reduction in leaf chlorophyll content (SPAD index). The stronger reduction of C. citrinus growth compared to V. lucidum, was due to an exacerbated reduction in net photosynthetic rate, driven by both stomatal and non stomatal limitations. In similar conditions, V. lucidum exhibited other additional adaptive response, such as modification in leaf functional anatomical traits, mostly related to the reduction in the stomata size allowing plants a better control of stomata opening than in C. citrinus. However, C. citrinus plants displayed an increased ability to retain higher Cl- levels in leaves than in roots under CaCl2 salinity compared to V. lucidum, thus, indicating a further attempt to counteract chloride toxicity through an increased vacuolar compartmentalization and to take advantages of them as chip osmotica.

This study was undertaken to investigate how different cultivars of sweet basil (Ocimum basilicum) responded to boron (B) excess. Two purple-leafed and eight green-leafed cultivars were hydroponically grown for 20 d with 0.2 or 20 mg L–1 B in the nutrient solution. Leaf B concentration, gas exchanges, chlorophyll a fluorescence, and oxidative stress were determined at the end of the treatment along with the severity of leaf necrosis. A range of tolerance to B toxicity was found: the green cultivars were more susceptible than the purple-leafed ones characterized by a higher constitutive anthocyanin concentration. In all the genotypes B excess resulted in oxidative stress as determined by accumulation of malondialdehyde by-products (MDA), reduced photosynthesis, and the occurrence of leaf burn. A close correlation was found between leaf B accumulation and oxidative stress, as well as between oxidative stress and the severity of leaf burn. Net photosynthesis (Pn) was reduced due to both stomatal and nonstomatal limitations in the green cultivars whereas the reduction of Pn in the purple leaves was only attributable to stomatal factors. Chlorophyll a fluorescence revealed a decrease in the maximum quantum yield of PSII (Fv/Fm) and in the electron transport rate (ETR) in plants grown with B excess although less reduction was observed in the purple genotypes. The quantum yield of PSII (UPSII) decreased as a result of B toxicity only in the green cultivars. It is concluded that anthocyanins are involved in attenuation of the negative effects of B toxicity.

The physiological response to physical exercise is now recognized as an important tool which can aid the diagnosis and treatment of cardiovascular diseases. This is due to the fact that several mechanisms are needed to accommodate a higher cardiac output and a higher oxygen delivery to tissues. The aim of the present work is to provide a fully closed loop cardiorespiratory simulator reproducing the main physiological mechanisms which arise during aerobic exercise. The simulator also provides a representation of the impairments of these mechanisms in heart failure condition and their effect on limiting exercise capacity. The simulator consists of a cardiovascular model including the left and right heart, pulmonary and systemic circulations. This latter is split into exercising and non-exercising regions and is controlled by the baroreflex and metabolic mechanisms. In addition, the simulator includes a respiratory model reproducing the gas exchange in lungs and tissues, the ventilation control and the effects of its mechanics on the cardiovascular system. The simulator was tested and compared to the data in the literature at three different workloads whilst cycling (25, 49 and 73 watts). The results show that the simulator is able to reproduce the response to exercise in terms of: heart rate (from 67 to 134 bpm), cardiac output (from 5.3 to 10.2 l/min), leg blood flow (from 0.7 to 3.0 l/min), peripheral resistance (from 0.9 to 0.5 mmHg/(cm(3)/s)), central arteriovenous oxygen difference (from 4.5 to 10.8 ml/dl) and ventilation (6.1-25.5 l/min). The simulator was further adapted to reproduce the main impairments observed in heart failure condition, such as reduced sensitivity of baroreflex and metabolic controls, lower perfusion to the exercising regions (from 0.6 to 1.4 l/min) and hyperventilation (from 9.2 to 40.2 l/min). The simulator we developed is a useful tool for the description of the basic physiological mechanisms operating during exercise. It can reproduce how these mechanisms interact and how their impairments could limit exercise performance in heart failure condition. The simulator can thus be used in the future as a test bench for different therapeutic strategies aimed at improving exercise performance in cardiopathic subjects. ispartof: Frontiers in Physiology vol:7 issue:JUN ispartof: location:Switzerland status: published

Forest functionality and productivity are directly related to canopy light interception and can be affected by potential damage from high irradiance. However, the mechanisms by which leaves adapt to the variable light environments along the multilayer canopy profile are still poorly known. We explored the leaf morphophysiological and metabolic responses to the natural light gradient in a pure European beech (Fagus sylvatica L.) forest at three different canopy heights (top, middle and bottom). Structural adjustment through light-dependent modifications in leaf mass per area was the reason for most of the variations in photosynthetic capacity. The different leaf morphology along the canopy influenced nitrogen (N) partitioning, water- and photosynthetic N-use efficiency, chlorophyll (Chl) fluorescence and quali-quantitative contents of photosynthetic pigments. The Chl a to Chl b ratio and the pool of xanthophyll-cycle pigments (VAZ) increased at the highest irradiance, as well as lutein and ?-carotene. The total pool of ascorbate and phenols was higher in leaves of the top and middle canopy layers when compared with the bottom layer, where the ascorbate peroxidase was relatively more activated. The non-photochemical quenching was strongly and positively related to the VAZ/(Chl a + b) ratio, while Chl a/Chl b was related to the photochemical efficiency of photosystem II. Along the multilayer canopy profile, the high energy dissipation capacity of leaves was correlated to an elevated redox potential of antioxidants. The middle layer gave the most relevant contribution to leaf area index and carboxylation capacity of the canopy. In conclusion, a complex interplay among structural, physiological and biochemical traits drives the dynamic leaf acclimation to the natural gradients of variable light environments along the tree canopy profile. The relevant differences observed in leaf traits within the canopy positions of the beech forest should be considered for improving estimation of carbon fluxes in multilayer canopy models of temperate forests.

In heart failure (HF), pulmonary hypertension (PH) is initially associated with a rise in the left ventricular filling pressure. PH is defined by pulmonary hemodynamic measurements including pulmonary capillary wedge pressure, mean pulmonary arterial pressure and pulmonary vascular resistance. Eventually, PH in HF may become more of a reactive process. Although the mechanism of the reactive PH development is not clearly understood, vascular dysfunction induced by remodeling, vasoactive substances and genetic variation appear to contribute significantly to this form of PH. Noninvasive cardiopulmonary exercise testing has been extensively utilized to assess disease severity in HF patients. It provides integrated information that is dependent on cardiopulmonary hemodynamics, lung mechanics, breathing pattern and strategy. In this review, we will discuss the mechanisms of PH development in HF and how noninvasive gas exchange measures obtained with submaximal exercise are influenced by PH in this population.

Introduction The cardiorespiratory exercise test provides valuable information in a rehabilitation program for chronic heart failure. It initially allows objective measurement of the patient's functional capacity by measuring VO 2 and ventilatory threshold. The description of respiratory adaptations gives informations on ventilatory efficiency and the existence of inadequate hyperventilation. Method This objective description of the performance and exercise tolerance will allow: to select patients to rehabilitate, provide prognostic information, choose retraining protocol best suited to the patient's situation, ensure monitoring by quantifying improved performance and tolerance to exercise and if necessary read just the terms of the retraining program. Results The contribution of this type of evaluation will be detailed in the different perspectives mentioned using concrete examples. These objective measures achieved in strict conditions allow to assess, select, guide and reassure, encourage patients to optimize their rehabilitation program. Conclusion The interest of the evaluation of endurance by measuring VO 2 and ventilatory threshold can be demonstrated at various stages of heart failure patients rehabilitation course.