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The Amazon forest contains globally important carbon stocks, but in recent years, atmospheric measurements suggest that it has been releasing more carbon than it has absorbed because of deforestation and forest degradation. Accurately attributing the sources of carbon loss to forest degradation and natural disturbances remains a challenge because of the difficulty of classifying disturbances and simultaneously estimating carbon changes. We used a unique, randomized, repeated, very high-resolution airborne laser scanning survey to provide a direct, detailed, and high-resolution partitioning of aboveground carbon gains and losses in the Brazilian Arc of Deforestation. Our analysis revealed that disturbances directly attributed to human activity impacted 4.2% of the survey area while windthrows and other disturbances affected 2.7% and 14.7%, respectively. Extrapolating the lidar-based statistics to the study area (544,300 km2), we found that 24.1, 24.2, and 14.5 Tg C y-1 were lost through clearing, fires, and logging, respectively. The losses due to large windthrows (21.5 Tg C y-1) and other disturbances (50.3 Tg C y-1) were partially counterbalanced by forest growth (44.1 Tg C y-1). Our high-resolution estimates demonstrated a greater loss of carbon through forest degradation than through deforestation and a net loss of carbon of 90.5 ± 16.6 Tg C y-1 for the study region attributable to both anthropogenic and natural processes. This study highlights the role of forest degradation in the carbon balance for this critical region in the Earth system.

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Sanitization using chemical agents to reduce the microbiological load on the surface of agricultural products have the drawback of leaving residues. Conversely, physical treatments, such as ultraviolet radiation C (UV-C), are residue-free, non-toxic and environmentally friendly. Ripe figs are perishable, exhibiting an epidermis with low resistance to mechanical treatment, high water content and the ostiole, which is an open door that expedites undesirable microorganism penetration. In this study, the effect of different energy levels of UV-C radiation on the appearance and physico-chemical properties of the figs when stored at 10 °C and 20 °C was evaluated focusing on the technological parameters of the application of radiation. The energy levels of radiation applied were 0.00, 0.71, 1.32, 2.64 and 4.01 kJ m−2 and they showed neither acceleration nor delay effects on fig ripening. Figs exposed to the radiation energy at 0.71, 1.32, 2.64 and 4.01 kJ m−2 showed a lower incidence of rot at the same temperature, but the figs exposed to the highest radiation, 4.01 kJ m−2, showed more wilting and stains, which significantly impaired their appearance. UV-C radiation reduces the development of rotting, providing evidence of its potential in the postharvest processing of ripe figs. However, radiation levels should be limited to avoid undesirable epidermis stains.

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Sanitization using chemical agents to reduce the microbiological load on the surface of agricultural products have the drawback of leaving residues. Conversely, physical treatments, such as ultraviolet radiation C (UV-C), are residue-free, non-toxic and environmentally friendly. Ripe figs are perishable, exhibiting an epidermis with low resistance to mechanical treatment, high water content and the ostiole, which is an open door that expedites undesirable microorganism penetration. In this study, the effect of different energy levels of UV-C radiation on the appearance and physico-chemical properties of the figs when stored at 10 °C and 20 °C was evaluated focusing on the technological parameters of the application of radiation. The energy levels of radiation applied were 0.00, 0.71, 1.32, 2.64 and 4.01 kJ m−2 and they showed neither acceleration nor delay effects on fig ripening. Figs exposed to the radiation energy at 0.71, 1.32, 2.64 and 4.01 kJ m−2 showed a lower incidence of rot at the same temperature, but the figs exposed to the highest radiation, 4.01 kJ m−2, showed more wilting and stains, which significantly impaired their appearance. UV-C radiation reduces the development of rotting, providing evidence of its potential in the postharvest processing of ripe figs. However, radiation levels should be limited to avoid undesirable epidermis stains.(AU)

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In tropical rainforests, tree size and number density are influenced by disturbance history, soil, topography, climate, and biological factors that are difficult to predict without detailed and widespread forest inventory data. Here, we quantify tree size-frequency distributions over an old-growth wet tropical forest at the La Selva Biological Station in Costa Rica by using an individual tree crown (ITC) algorithm on airborne lidar measurements. The ITC provided tree height, crown area, the number of trees >10 m height and, predicted tree diameter, and aboveground biomass from field allometry. The number density showed strong agreement with field observations at the plot- (97.4%; 3% bias) and tree-height-classes level (97.4%; 3% bias). The lidar trees size spectra of tree diameter and height closely follow the distributions measured on the ground but showed less agreement with crown area observations. The model to convert lidar-derived tree height and crown area to tree diameter produced unbiased (0.8%) estimates of plot-level basal area and with low uncertainty (6%). Predictions on basal area for tree height classes were also unbiased (1.3%) but with larger uncertainties (22%). The biomass estimates had no significant bias at the plot- and tree-height-classes level (-5.2% and 2.1%). Our ITC method provides a powerful tool for tree- to landscape-level tropical forest inventory and biomass estimation by overcoming the limitations of lidar area-based approaches that require local calibration using a large number of inventory plots.

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Large trees, here defined as ≥60 cm trunk diameter, are the most massive organisms in tropical rain forest, and are important in forest structure, dynamics and carbon cycling. The status of large trees in tropical forest is unclear, with both increasing and decreasing trends reported. We sampled across an old-growth tropical rain forest landscape at the La Selva Biological Station in Costa Rica to study the distribution and performance of large trees and their contribution to forest structure and dynamics. We censused all large trees in 238 0.50 ha plots, and also identified and measured all stems ≥10 cm diameter in 18 0.50 ha plots annually for 20 years (1997-2017). We assessed abundance, species diversity, and crown conditions of large trees in relation to soil type and topography, measured the contribution of large trees to stand structure, productivity, and dynamics, and analyzed the decadal population trends of large trees. Large trees accounted for 2.5% of stems and ~25% of mean basal area and Estimated Above-Ground Biomass, and produced ~10% of the estimated wood production. Crown exposure increased with stem diameter but predictability was low. Large tree density was about twice as high on more-fertile flat sites compared to less fertile sites on slopes and plateaus. Density of large trees increased 27% over the study interval, but the increase was restricted to the flat more-fertile sites. Mortality and recruitment differed between large trees and smaller stems, and strongly suggested that large tree density was affected by past climatic disturbances such as large El Niño events. Our results generally do not support the hypothesis of increasing biomass and turnover rates in tropical forest. We suggest that additional landscape-scale studies of large trees are needed to determine the generality of disturbance legacies in tropical forest study sites.

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[This corrects the article DOI: 10.1371/journal.pone.0221218.].

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Chronic critical illness (CCI) is a relevant clinical, social and financial health issue. The aim of this study was to compare the mental outcomes (symptoms of anxiety and depression) and quality of life outcomes of the family members of patients with CCI from different socioeconomic backgrounds who were admitted to one of the intensive care units (ICUs) in two Brazilian hospitals, one private and one public. It is a prospective study involving a public hospital that serves a low-income population and a tertiary private hospital that serves a high-income population. Family members of patients with CCI answered the Hospital Anxiety and Depression Scale (HADS) and The World Health Organization Quality of Life-WHOQOL-bref questionnaires. They responded to the European Quality of life Five Dimension three Level (EuroQol-5D-3L) and the Activities of Daily Living (ADL) questionnaires on behalf of the patients at three time points: during the ICU stay, 30 and 90 days after the patient was discharged. We used logistic regression models to evaluate the main predictors of a binary outcome regarding symptoms of anxiety and depression. We enrolled 186 patients with CCI. Many patients from public hospitals who were independent became dependent for their ADLs at 90 days (41.7% versus 14.3%, p = 0.03). At 30 days, family members from public hospital had worse impact on all domains of WHOQOL-bref compared with families from private hospital. At 90-days, the difference persists in the physical domain, worse for families from public hospital (p = 0.006). The symptoms of depression at 30-days (p = 0.008) and at 90-days (p = 0.013) were worse in the public hospital. CCIs affected quality of life and the emotional condition of family members, especially in families with fewer resources when the patients became more dependent. Family members with higher education were more likely to experience depression, while depression was associated with cohabiting with the patient in low-income families.

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BACKGROUND: Wet tropical forests of Chocó, along the Pacific Coast of Colombia, are known for their high plant diversity and endemic species. With increasing pressure of degradation and deforestation, these forests have been prioritized for conservation and carbon offset through Reducing Emissions from Deforestation and forest Degradation (REDD+) mechanisms. We provide the first regional assessment of forest structure and aboveground biomass using measurements from a combination of ground tree inventories and airborne Light Detection and Ranging (Lidar). More than 80,000 ha of lidar samples were collected based on a stratified random sampling to provide a regionally unbiased quantification of forest structure of Chocó across gradients of vegetation structure, disturbance and elevation. We developed a model to convert measurements of vertical structure of forests into aboveground biomass (AGB) for terra firme, wetlands, and mangrove forests. We used the Random Forest machine learning model and a formal uncertainty analysis to map forest height and AGB at 1-ha spatial resolution for the entire pacific coastal region using spaceborne data, extending from the coast to higher elevation of Andean forests. RESULTS: Upland Chocó forests have a mean canopy height of 21.8 m and AGB of 233.0 Mg/ha, while wetland forests are characterized by a lower height and AGB (13.5 m and 117.5 Mg/a). Mangroves have a lower mean height than upland forests (16.5 m), but have a similar AGB as upland forests (229.9 Mg/ha) due to their high wood density. Within the terra firme forest class, intact forests have the highest AGB (244.3 ± 34.8 Mg/ha) followed by degraded and secondary forests with 212.57 ± 62.40 Mg/ha of biomass. Forest degradation varies in biomass loss from small-scale selective logging and firewood harvesting to large-scale tree removals for gold mining, settlements, and illegal logging. Our findings suggest that the forest degradation has already caused the loss of more than 115 million tons of dry biomass, or 58 million tons of carbon. CONCLUSIONS: Our assessment of carbon stocks and forest degradation can be used as a reference for reporting on the state of the Chocó forests to REDD+ projects and to encourage restoration efforts through conservation and climate mitigation policies.

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The baru tree fruit has a sustainable economical potential. However, the shelling process to release the whole kernel, the most valued part of the fruit, is still performed in a rather inefficient way. The objective of this investigation was to determine the physical-mechanical properties of the fruit to understand its behavior during shelling. Fruit and nut were characterized by unit mass, dimensions, volume and bulk, and real densities. Compression tests up to endocarp disruption were performed to determine maximum force, corresponding deformation, and deformation energy. X-ray tomography was used to identify potential nut internal dimension changes, affected by the treatments. Whole fruits and nuts showed average unit mass values of 28.20 ± 0.99 g and 16.52 ± 1.67 g, respectively. Their average dimensions, such as length, width, and thickness were 52.40 ± 4.48 mm, 38.31 ± 4.05 mm, and 28.64 ± 3.67 mm, and 50.78 ± 5.57 mm, 34.65 ± 5.14 mm, and 21.36 ± 2.86 mm, respectively. Average bulk and real densities values were 519.33 ± 49.63 kg/m3 and 918.87 ± 77.77 kg/m3, and 517.14 ± 41.88 kg/m3 and 1072.00 ± 187.01 kg/m3, respectively. Considering all treatments, the average rupture force ranged between 7926.7 and 9284.4 N, with corresponding widthwise specific deformation of 5.1% and 6.6%, to release 100% whole kernels of the tested nuts. Up to maximum force, deformation energy values ranged between 6.55 and 9.26J. There was no evidence of treatments effect on the internal dimension.Based on its mechanical behavior, showing that it is possible to open the endocarp and release the wholekernel, it was concluded that the baru nut has mechanized shelling potential.(AU)

O fruto do baruzeiro apresenta potencial econômico sustentável, mas o processo de decorticação com liberação de amêndoa inteira, a parte mais valiosa, é ainda realizada de forma um tanto ineficiente. O objetivo nesta investigação foi determinar suas propriedades físico-mecânicas visando compreensão do seu comportamento durante a decorticação. Fruto e castanha foram caracterizados pela massa, volume e dimensões unitários e massas específicas aparente e real. Ensaios de compressão até a ruptura do endocarpo foram realizados para determinar a força máxima, deformações correspondentes e energia de deformação. Utilizou-se da tomografia de raio-X para investigar potenciais modificações, causadas pelos tratamentos, nas dimensões internas. Fruto e castanha apresentaram massa unitária média de 28,20 ± 0,99 e 16,52 ± 1,67 g, respectivamente. O comprimento, a largura e a espessura médias foram 52,40 ± 4,48, 38,31 ± 4,05 e 28,64 ± 3,67 mm, e 50,78 ± 5,57, 34,65 ± 5,14 e 21,36 ± 2,86 mm, respectivamente. Os valores médios das massas específicas aparente e real foram 519,33 ± 49,63 e 918,87 ± 77,77 kg/m3, e 517,14 ± 41,88 e 1072,00 ± 187,01 kg/m3, respectivamente. Considerando todos os condicionamentos, a força média de ruptura do endocarpo variou entre 7926,7 e 9284,4 N, com deformação específica entre 5,1 e 6,6% da largura para a obtenção de 100% de amêndoas inteiras. Os valores médios de energia dedeformação até a força máxima variaram entre 6,55 e 9,26 J. Não foi possível evidenciar os efeitos dosdiversos condicionamentos nas dimensões internas. Devido ao seu comportamento mecânico evidenciara possibilidade de abertura do endocarpo com liberação de amêndoa inteira, concluiu-se que existepotencial para a decorticação mecanizada da castanha de baru.(AU)

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Azo dyes, which are widely used in the textile industry, exhibit significant toxic characteristics for the environment and the human population. Sequential anaerobic-aerobic reactor systems are efficient for the degradation of dyes and the mineralization of intermediate compounds; however, little is known about the composition of the microbial communities responsible for dye degradation in these systems. 454-Pyrosequencing of the 16S rRNA gene was employed to assess the bacterial biodiversity and composition of a two-stage (anaerobic-aerobic) pilot-scale reactor that treats effluent from a denim factory. The anaerobic reactor was inoculated with anaerobic sludge from a domestic sewage treatment plant. Due to the selective composition of the textile wastewater, after 210 days of operation, the anaerobic reactor was dominated by the single genus Clostridium, affiliated with the Firmicutes phylum. The aerobic biofilter harbored a diverse bacterial community. The most abundant phylum in the aerobic biofilter was Proteobacteria, which was primarily represented by the Gamma, Delta and Epsilon classes followed by Firmicutes and other phyla. Several bacterial genera were identified that most likely played an essential role in azo dye degradation in the investigated system.

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