10 research outputs found
Glow discharge in low pressure plasma PVD: mathematical model and numerical simulations
In this paper we analyze the problem of glow discharge in low pressure plasma
in industrial plant, for chambers of different shapes and various working
parameters, like pressure and electric potential. The model described is based
upon a static approximation of the AC configuration with two electrodes and a
drift diffusion approximation for the current density of positive ions and
electrons. A detailed discussion of the boundary conditions imposed is given,
as well as the full description of the mathematical model. Numerical
simulations were performed for a simple 1D model and two different 2D models,
corresponding to two different settings of the industrial plant. The simpler
case consists of a radially symmetric chamber, with one central electrode
(cathode), based upon a DC generator. In this case, the steel chamber acts as
the anode. The second model concerns a two dimensional horizontal cut of the
most common plant configuration, with two electrodes connected to an AC
generator. The case is treated in a "quasi-static" approximation. The three
models show some common behaviours, particularly including the main expected
features, such as dark spaces, glow regions and a wide "plasma region".
Furthermore, the three shown models show some similarities with previously
published results concerning 1D and simplified 2D models, as well as with some
preliminary results of the full 3D case.Comment: 16 pages, 11 figures, in pres
Lost in authoritarian development:Have global climate deals and the aid community sacrificed the Vietnamese highland population?
Derivation of Isothermal Quantum Fluid Equations with Fermi-Dirac and Bose-Einstein Statistics
Hot topics in governance for forests and trees: Towards a (just) transformative research agenda
We are living in a time of crisis on planet Earth. Urgent calls for transformational change are getting louder. Technical solutions have an important role to play in addressing pressing global challenges, but alone they are not enough. After all, who decides what kind of transformation is needed, of what, and for whom? What principles guide those decisions, and how are decision-makers held accountable? This commentary article argues that these governance questions are central in any solution, in order to simultaneously address the planetary crises of forest and biodiversity loss and degradation and growing inequality. To this end, we examine governance in forests and around trees, in landscapes and on farms, through the lens of power and social justice. For applied research aimed at actionable solutions to these global problems, we propose a governance research agenda for the next decade that is both transformative and just
FTA Highlight No.14 – Governing forests, trees and agroforestry for delivering on the SDGs
This publication presents the results of FTA’s work across the humid tropics in the area of enhancing the good governance of forests, trees and agroforestry, typically as part of landscapes that deliver on sustainable development goals. Work on the interface of the science and policy arenas focused on enabling good governance in landscapes through five principles: legitimacy and voice, strategic direction, performance, accountability and fairness. This publication presents and discusses the main achievements in terms of contributions to research, innovation and actual impact on good governance at the landscape, subnational, national and supra-national levels. A decade of FTA involvement has contributed substantively to the development of national agroforestry policies in a number of countries, including India (the world’s first-ever national agroforestry policy)1 and Nepal. Maldives, Gambia, Kenya and Rwanda have also embarked on national strategies with FTA support. The Association of Southeast Asian Nations (ASEAN) has also adopted agroforestry guidelines. In Peru agroforestry concession schemes were introduced to formalize agriculture and timber production on forest lands as a means of reducing deforestation and forest degradation, and the country also adopted a comprehensive definition of agroforestry in its National Agricultural Policy. FTA also supported the development of national bioenergy strategies in Viet Nam and Kenya. The FTA program has also significantly influenced thinking on payment for ecosystem services, coinvestment in ecosystem service stewardship, incentives, community forestry and certification of forests and tree commodities worldwide. Green growth planning approaches have also been integrated into subnational-level planning in Indonesia and Viet Nam. Adoption of multistakeholder forum methodologies in forest landscape planning at subnational levels in Peru, as well as community forestry approaches in Cameroon and Indonesia, also show FTA’s contributions to methodological approaches. These results contribute to improved enabling institutional, political and socioeconomic environments for more effective and efficient natural resource management, and hence positively affect livelihoods in multiple countries across the humid tropics
Post-anaesthesia pulmonary complications after use of muscle relaxants (POPULAR): a multicentre, prospective observational study
Background: Results from retrospective studies suggest that use of neuromuscular blocking agents during general anaesthesia might be linked to postoperative pulmonary complications. We therefore aimed to assess whether the use of neuromuscular blocking agents is associated with postoperative pulmonary complications. Methods: We did a multicentre, prospective observational cohort study. Patients were recruited from 211 hospitals in 28 European countries. We included patients (aged ≥18 years) who received general anaesthesia for any in-hospital procedure except cardiac surgery. Patient characteristics, surgical and anaesthetic details, and chart review at discharge were prospectively collected over 2 weeks. Additionally, each patient underwent postoperative physical examination within 3 days of surgery to check for adverse pulmonary events. The study outcome was the incidence of postoperative pulmonary complications from the end of surgery up to postoperative day 28. Logistic regression analyses were adjusted for surgical factors and patients' preoperative physical status, providing adjusted odds ratios (ORadj) and adjusted absolute risk reduction (ARRadj). This study is registered with ClinicalTrials.gov, number NCT01865513. Findings: Between June 16, 2014, and April 29, 2015, data from 22 803 patients were collected. The use of neuromuscular blocking agents was associated with an increased incidence of postoperative pulmonary complications in patients who had undergone general anaesthesia (1658 [7·6%] of 21 694); ORadj 1·86, 95% CI 1·53–2·26; ARRadj −4·4%, 95% CI −5·5 to −3·2). Only 2·3% of high-risk surgical patients and those with adverse respiratory profiles were anaesthetised without neuromuscular blocking agents. The use of neuromuscular monitoring (ORadj 1·31, 95% CI 1·15–1·49; ARRadj −2·6%, 95% CI −3·9 to −1·4) and the administration of reversal agents (1·23, 1·07–1·41; −1·9%, −3·2 to −0·7) were not associated with a decreased risk of postoperative pulmonary complications. Neither the choice of sugammadex instead of neostigmine for reversal (ORadj 1·03, 95% CI 0·85–1·25; ARRadj −0·3%, 95% CI −2·4 to 1·5) nor extubation at a train-of-four ratio of 0·9 or more (1·03, 0·82–1·31; −0·4%, −3·5 to 2·2) was associated with better pulmonary outcomes. Interpretation: We showed that the use of neuromuscular blocking drugs in general anaesthesia is associated with an increased risk of postoperative pulmonary complications. Anaesthetists must balance the potential benefits of neuromuscular blockade against the increased risk of postoperative pulmonary complications. Funding: European Society of Anaesthesiology
Post-anaesthesia pulmonary complications after use of muscle relaxants (POPULAR): a multicentre, prospective observational study
Background Results from retrospective studies suggest that use of neuromuscular blocking agents during general anaesthesia might be linked to postoperative pulmonary complications. We therefore aimed to assess whether the use of neuromuscular blocking agents is associated with postoperative pulmonary complications.Methods We did a multicentre, prospective observational cohort study. Patients were recruited from 211 hospitals in 28 European countries. We included patients (aged >= 18 years) who received general anaesthesia for any in-hospital procedure except cardiac surgery. Patient characteristics, surgical and anaesthetic details, and chart review at discharge were prospectively collected over 2 weeks. Additionally, each patient underwent postoperative physical examination within 3 days of surgery to check for adverse pulmonary events. The study outcome was the incidence of postoperative pulmonary complications from the end of surgery up to postoperative day 28. Logistic regression analyses were adjusted for surgical factors and patients' preoperative physical status, providing adjusted odds ratios (ORadj) and adjusted absolute risk reduction (ARR(adj)). This study is registered with ClinicalTrials. gov, number NCT01865513.Findings Between June 16, 2014, and April 29, 2015, data from 22 803 patients were collected. The use of neuromuscular blocking agents was associated with an increased incidence of postoperative pulmonary complications in patients who had undergone general anaesthesia (1658 [7.6%] of 21 694); ORadj 1.86, 95% CI 1.53-2.26; ARR(adj) -4.4%, 95% CI -5.5 to -3.2). Only 2.3% of high-risk surgical patients and those with adverse respiratory profiles were anaesthetised without neuromuscular blocking agents. The use of neuromuscular monitoring (ORadj 1.31, 95% CI 1.15-1.49; ARR(adj) -2.6%, 95% CI -3.9 to -1.4) and the administration of reversal agents (1.23, 1.07-1.41; -1.9%, -3.2 to -0.7) were not associated with a decreased risk of postoperative pulmonary complications. Neither the choice of sugammadex instead of neostigmine for reversal (ORadj 1.03, 95% CI 0.85-1 center dot 25; ARR(adj) -0.3%, 95% CI -2.4 to 1.5) nor extubation at a train-of-four ratio of 0.9 or more (1.03, 0.82-1.31; -0.4%, -3.5 to 2.2) was associated with better pulmonary outcomes.Interpretation We showed that the use of neuromuscular blocking drugs in general anaesthesia is associated with an increased risk of postoperative pulmonary complications. Anaesthetists must balance the potential benefits of neuromuscular blockade against the increased risk of postoperative pulmonary complications