18 research outputs found

    Herschel water maps towards the vicinity of the black hole Sgr A*

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    Aims: We study the spatial distribution and kinematics of water emission in a ~64 pc2^2 region of the Galactic Center (GC) around Sgr A*. We also analyze the water excitation to derive the physical conditions and water abundances in the CND and the `quiescent clouds'. Methods: We presented the integrated intensity maps of the ortho 110101_{10}-1_{01}, and para 202111_{02}-1_{11} and 111000_{11}-0_{00} water transitions observed with the HIFI instrument on board Herschel. To study the water excitation we used ground state ortho and para H218_2^{18}O transitions. In our study, we also used SPIRE continuum measurements of the CND. Using a non-LTE radiative transfer code, the water line profiles and dust continuum were modeled. We also used a rotating ring model to reproduce the CND kinematics represented by the PV diagram. Results: We identify the water emission arising from the CND, the Western Streamer, and the 20 and 50 km s1^{-1} clouds. The ortho water maps show absorption structures in the range of [-220,10] km s1^{-1}. The PV diagram shows that the 202111_{02}-1_{11} H2_2O emission traces the CND. We derive high XH2O_{H_2O} of \sim(0.1-1.3)×\times105^{-5}, Vt_t of 14-23 km s1^{-1} and Td_d of 15-45 K for the CND, and the lower XH2O_{\rm H_2O} of 4×\times108^{-8} and Vt_t of 9 km s1^{-1} for the 20 km s1^{-1} cloud. Collisional excitation and dust effects are responsible for the water excitation in the southwest lobe of the CND and the 20 km s1^{-1} cloud, whereas only collisions can account for the water excitation in the northeast lobe of the CND. We propose that the water vapor in the CND is caused by grain sputtering by shocks of 10-20 km s1^{-1}, with some contribution of high temperature and cosmic-ray chemistries plus a PDR chemistry. The low XH2O_{\rm H_2O} derived for the 20 km s1^{-1} cloud could be partially a consequence of the water freeze-out on grains.Comment: 15 pages, 11 figure

    Global urban environmental change drives adaptation in white clover.

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    Urbanization transforms environments in ways that alter biological evolution. We examined whether urban environmental change drives parallel evolution by sampling 110,019 white clover plants from 6169 populations in 160 cities globally. Plants were assayed for a Mendelian antiherbivore defense that also affects tolerance to abiotic stressors. Urban-rural gradients were associated with the evolution of clines in defense in 47% of cities throughout the world. Variation in the strength of clines was explained by environmental changes in drought stress and vegetation cover that varied among cities. Sequencing 2074 genomes from 26 cities revealed that the evolution of urban-rural clines was best explained by adaptive evolution, but the degree of parallel adaptation varied among cities. Our results demonstrate that urbanization leads to adaptation at a global scale

    Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

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    Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

    Global urban environmental change drives adaptation in white clover

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    Urbanization transforms environments in ways that alter biological evolution. We examined whether urban environmental change drives parallel evolution by sampling 110,019 white clover plants from 6169 populations in 160 cities globally. Plants were assayed for a Mendelian antiherbivore defense that also affects tolerance to abiotic stressors. Urban-rural gradients were associated with the evolution of clines in defense in 47% of cities throughout the world. Variation in the strength of clines was explained by environmental changes in drought stress and vegetation cover that varied among cities. Sequencing 2074 genomes from 26 cities revealed that the evolution of urban-rural clines was best explained by adaptive evolution, but the degree of parallel adaptation varied among cities. Our results demonstrate that urbanization leads to adaptation at a global scale

    Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

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    Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

    Cerca del Rio y Lejos del Agua: Water, Autonomy and Hope in the Ecuadorian Andes

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    Community water associations perform a pivotal role in the delivery of water services in the rural Ecuadorian Andes. The water that they deliver to houses and farmers is the fruit of a historical process of collective organisation that has united rural families and communities in a struggle to overcome socially constructed water scarcity. Through this ongoing struggle, water associations have developed varying degrees and forms of collective autonomy. Not only has this enabled them to distribute potable and irrigation water, but also create new social and political practices and relations. Drawing on the innovative work of Ana C. Dinerstein, this chapter traces the contours of this historical process, explaining how water associations have carved out space to take autonomous control of local water supplies and reconfigure relations with the state and nature

    Analysis of risk and disaster reduction strategies in South American countries

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    There is a growing interest in disaster risk management due to an increasing vulnerability to extreme natural events and man-made disasters that prevent normal relations in societies worldwide. Thus, this study aimed to analyze disaster risk reduction (DRR) strategies in the context of seven Spanish-speaking South American countries, namely Argentina, Bolivia, Colombia, Chile, Ecuador, Paraguay, and Peru. We conducted an analysis of different DRR plans by using text mining techniques. Textual processing of the DRR strategies was conducted using computer-assisted qualitative data analysis. This process was complemented with the use of statistical models, such as the hierarchical cluster analysis and multiple correspondence analysis. Among the main results, 87 DRR strategies were found in the selected countries. The categorization of these strategies were different based on four management planning elements: planning based on social participation and stakeholder management, management planning based on disaster response, post-disaster continuity management planning, and management planning of essential sector continuity. Thus, this paper highlights the region\u27s strengths and weaknesses and serves as a basis to follow up on the 2030 agenda for DRR discussed at Sendai in 2015
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