Aplicação de índices espectrais na avaliação do aporte de sedimento aos reservatórios das Usinas Hidrelétricas Itumbiara e Batalha (Brasil)

In this work, two spectral indexes were implemented using Landsat images, the Normalized Difference Water Index (NDWI) for the delimitation of the water mirror and the Normalized Difference Turbidity Index (NDTI) to evaluate the sediment contribution to the reservoirs of the hydroelectric power plants Itumbiara and Batalha, located on the borders of the states of Goiás and Minas Gerais. The acquisition and processing were carried out in the Google Earth Engine platform and the post-processing in the QGIS software. The NDTI was applied to the reservoirs considering the variation in water level between the dry and rainy seasons in 2020. The highest concentration of turbidity in the Itumbiara reservoir occurred in September, and the lowest in June. August was the month with the highest turbidity concentration and July the lowest in the Batalha reservoir.En este trabajo se implementaron dos índices espectrales utilizando imágenes Landsat, el Índice de Diferencia de Agua Normalizada (NDWI) para la delimitación del espejo de agua y el Índice de Turbidez de Diferencia Normalizada (NDTI) para evaluar el aporte de sedimentos a los embalses de las centrales hidroeléctricas Itumbiara y Batalha, ubicadas en los límites de los estados de Goiás y Minas Gerais. El NDTI se aplicó en los embalses considerando la variación del nivel del agua entre las épocas seca y lluviosa de 2020. La mayor concentración de turbiedad en el embalse de Itumbiara se presentó en septiembre y la menor en junio, siendo agosto el mes con mayor concentración de turbidez y julio con la menor en el embalse de Batalha.Dans ce travail, deux indices spectraux ont été implémentés à l'aide d'images Landsat, le Normalized Difference Water Index (NDWI) pour la délimitation du miroir d'eau et le Normalized Difference Turbidity Index (NDTI) pour évaluer la contribution des sédiments aux réservoirs des centrales hydroélectriques. Itumbiara et Batalha, situées aux confins des états de Goiás et Minas Gerais. Le NDTI a été appliqué dans les réservoirs en tenant compte de la variation du niveau d'eau entre les saisons sèche et pluvieuse de 2020. La plus forte concentration de turbidité dans le réservoir d'Itumbiara s'est produite en septembre et la plus faible en juin. Dans le réservoir de Batalha, août étant le mois avec la plus forte concentration de turbidité et la plus faible en juillet.In questo lavoro sono stati implementati due indici spettrali utilizzando immagini Landsat, il Normalized Difference Water Index (NDWI) per la delimitazione dello specchio d'acqua e il Normalized Difference Turbidity Index (NDTI) per valutare il contributo dei sedimenti ai serbatoi delle Centrali Idroelettriche Itumbiara e Batalha, situate ai confini degli stati di Goiás e Minas Gerais. L'acquisizione e l'elaborazione sono state effettuate nella piattaforma Google Earth Engine e la post-elaborazione nel QGIS. L'NDTI è stato applicato nei bacini considerando la variazione del livello dell'acqua tra la stagione secca e quella piovosa del 2020. La più alta concentrazione di torbidità nel bacino di Itumbiara si è verificata a settembre, e la più bassa a giugno. Nel bacino di Batalha, agosto è il mese con la più alta concentrazione di torbidità e il più basso a luglio.Neste trabalho foram implementados dois índices espectrais utilizando imagens Landsat, o Índice da Diferença Normalizada de Água (NDWI) para delimitação do espelho d’água e o Índice de Turbidez por Diferença Normalizada (NDTI) para avaliação do aporte de sedimentos aos reservatórios das Usinas Hidrelétricas Itumbiara e Batalha, localizadas nas divisas dos estados de Goiás e Minas Gerais. A aquisição e o processamento foram realizados na plataforma Google Earth Engine e o pós-processamento no software QGIS. O NDTI foi aplicado nos reservatórios considerando a variação do nível de água entre as estações seca e chuvosa de 2020. A maior concentração de turbidez no reservatório de Itumbiara se deu em setembro, e a menor em junho. Já no reservatório de Batalha, sendo agosto o mês com maior concentração de turbidez, e a menor em julho

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost

Efficacy of Baccharis dracunculifolia in the treatment of diversion colitis in rats

Rationale: Disuse colitis is frequent in our country and the most effective treatment is high cost and there is a need for effective and low cost therapy. Objective: To evaluate the efficacy of Baccharis dracunculifolia (field rosemary) in the treatment of exclusion colitis in rats. Method: Eighteen Wistar rats were anesthetized and submitted to colostomy; they were then distributed into two groups: Control Group, receiving intrarectal saline infusion (n = 8) and Group BD receiving intrarectal infusion ofBaccharis dracunculifolia extract (n = 10); after 21 days of treatment they were euthanized, the intestinal segment excluded from intestinal transit was resected and submitted to histopathological study, classifying the degree of inflammation and degree of vascular congestion from 0 to 3. Results: Mean inflammation was 2.7 in Control Group versus 2.1 in BD Group (p = 0.049), while mean vascular congestion was 2.3 and 2, respectively, in Control and BD groups (p = 0.1642). Conclusion: Intra-rectal infusion ofBaccharis dracunculifolia extract significantly minimized the inflammatory process in the exclusion colitis of rats submitted to colostomy, without altering the degree of vascular congestion. Resumo: Racional: A colite de desuso é frequente em nosso meio e o tratamento de maior eficácia é de alto custo, havendo necessidade de se encontrar uma terapêutica eficaz e de baixo custo. Objetivo: Avaliar a eficácia da Baccharis dracunculifolia (alecrim-do-campo) no tratamento da colite de exclusão em ratos. Método: Utilizou-se 18 ratos Wistar, os quais foram anestesiados e submetidos à colostomia; em seguida distribuídos em 2 grupos: Grupo Controle, recebendo infusão intrarretal de solução salina (n = 8) e Grupo BD, recebendo infusão intrarretal de extrato de Baccharis dracunculifolia (n = 10); após 21 dias de tratamento foram submetidos a eutanásia, o segmento intesinal excluso de trânsito intestinal foi ressecado e submetido a estudo histopatológico classificando-se o grau de inflamação e grau de congestão vascular de 0 a 3. Resultados: Verificou-se média de inflamação 2,7 no Grupo Controle vs. 2,1 no Grupo BD (p = 0,049), enquanto as médias de congestão vascular foram 2,3 e 2, respectivamente, nos grupos controle e BD (p = 0,1642). Conclusão: A infusão intrarretal do extrato de Baccharis dracunculifolia minimizou significantemente o processo inflamatório na colite de exclusão de ratos submetidos à colostomia, sem alterar o grau de congestão vascular. Keywords: Baccharis dracunculifolia, Asteraceae, Colitis, Anti-inflammatory, Rats, Colostomy, Palavras-chave: Baccharis dracunculifolia, Asteraceae, Colite, Anti-inflamatórios, Ratos, Colostomi

Effect of lung recruitment and titrated Positive End-Expiratory Pressure (PEEP) vs low PEEP on mortality in patients with acute respiratory distress syndrome - A randomized clinical trial

IMPORTANCE: The effects of recruitment maneuvers and positive end-expiratory pressure (PEEP) titration on clinical outcomes in patients with acute respiratory distress syndrome (ARDS) remain uncertain. OBJECTIVE: To determine if lung recruitment associated with PEEP titration according to the best respiratory-system compliance decreases 28-day mortality of patients with moderate to severe ARDS compared with a conventional low-PEEP strategy. DESIGN, SETTING, AND PARTICIPANTS: Multicenter, randomized trial conducted at 120 intensive care units (ICUs) from 9 countries from November 17, 2011, through April 25, 2017, enrolling adults with moderate to severe ARDS. INTERVENTIONS: An experimental strategy with a lung recruitment maneuver and PEEP titration according to the best respiratory-system compliance (n = 501; experimental group) or a control strategy of low PEEP (n = 509). All patients received volume-assist control mode until weaning. MAIN OUTCOMES AND MEASURES: The primary outcome was all-cause mortality until 28 days. Secondary outcomes were length of ICU and hospital stay; ventilator-free days through day 28; pneumothorax requiring drainage within 7 days; barotrauma within 7 days; and ICU, in-hospital, and 6-month mortality. RESULTS: A total of 1010 patients (37.5% female; mean [SD] age, 50.9 [17.4] years) were enrolled and followed up. At 28 days, 277 of 501 patients (55.3%) in the experimental group and 251 of 509 patients (49.3%) in the control group had died (hazard ratio [HR], 1.20; 95% CI, 1.01 to 1.42; P = .041). Compared with the control group, the experimental group strategy increased 6-month mortality (65.3% vs 59.9%; HR, 1.18; 95% CI, 1.01 to 1.38; P = .04), decreased the number of mean ventilator-free days (5.3 vs 6.4; difference, −1.1; 95% CI, −2.1 to −0.1; P = .03), increased the risk of pneumothorax requiring drainage (3.2% vs 1.2%; difference, 2.0%; 95% CI, 0.0% to 4.0%; P = .03), and the risk of barotrauma (5.6% vs 1.6%; difference, 4.0%; 95% CI, 1.5% to 6.5%; P = .001). There were no significant differences in the length of ICU stay, length of hospital stay, ICU mortality, and in-hospital mortality. CONCLUSIONS AND RELEVANCE: In patients with moderate to severe ARDS, a strategy with lung recruitment and titrated PEEP compared with low PEEP increased 28-day all-cause mortality. These findings do not support the routine use of lung recruitment maneuver and PEEP titration in these patients. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01374022