312 research outputs found
Contribution of advanced regeneration of Pinus Radiata D. Don. to transpiration by a fragment of Native forest in central Chile is out of proportion with the contribution to sapwood area
The transpiration of Nothofagus glauca (Phil.) Krasser and advanced Pinus radiata D. Don. regeneration was measured in a fragment of native N. glauca forest. Over the eight months of this study, P. radiata contributed approximately 60% of the total stand transpiration. This was out of proportion with the approximately 34% of the stand sapwood area contributed by P. radiata. This was due to the significantly greater sap flux density of the P. radiata compared to the N. glauca between May and October. Though the results are from a small study conducted as part of a larger experiment, it is argued that they suggest that invasion by P. radiata may substantially increase the risk from climate change to reserves of N. glauca forest in the Maule region of central Chile. In some reserves of N. glauca forest, Forestal Arauco S.A. manually removed P. radiata that regenerated after the wildfire of January 2017. This was a costly operation and there is a need for indices to assess competition. The ratio of sapwood area to leaf area is suggested as a potential index for assessing competition to identify stands at risk. © 2020 by the author
Is the reputation of Eucalyptus plantations for using more water than Pinus plantations justified?
The effect of Eucalyptus plantations on water balance is thought to be more severe than for commercial alternatives such as Pinus species. Although this perception is firmly entrenched, even in the scientific community, only four direct comparisons of the effect on the water balance of a Eucalyptus species and a commercial alternative have been published. One of these, from South Africa, showed that Eucalyptus grandis caused a larger and more rapid reduction in streamflow than Pinus patula. The other three, one in South Australia and two in Chile, did not find any significant difference between the annual evapotranspiration of E. globulus and P. radiata after canopy closure. While direct comparisons are few, there are at least 57 published estimates of annual evapotranspiration of either a Eucalyptus or Pinus species. This paper presents a meta-analysis of these published data. Zhang et al. (2004) fitted a relationship between the crop factor and the climate wetness index to published data from catchment studies and proposed this approach for comparing land uses. We fitted the same model to the published data for Eucalyptus and Pinus and found that the single parameter of this model did not differ significantly between the two genera (p=0.48). This implies that for a given climate wetness index the two genera have similar annual water use. The residuals compared to this model were significantly correlated with soil depth for Eucalyptus, but this was not the case for Pinus. For Eucalyptus the model overestimates the crop factor on deep soils and underestimates the crop factor on shallow soils.</p
Is the reputation of Eucalyptus plantations for using more water than Pinus plantations justified?
The effect of Eucalyptus plantations on water balance is thought to be more severe than for commercial alternatives such as Pinus species. Although this perception is firmly entrenched, even in the scientific community, only four direct comparisons of the effect on the water balance of a Eucalyptus species and a commercial alternative have been published. One of these, from South Africa, showed that Eucalyptus grandis caused a larger and more rapid reduction in streamflow than Pinus patula. The other three, one in South Australia and two in Chile, did not find any significant difference between the annual evapotranspiration of E. globulus and P. radiata after canopy closure. While direct comparisons are few, there are at least 57 published estimates of annual evapotranspiration of either the Eucalyptus or Pinus species. This paper presents a meta-analysis of these published data. Zhang et al. (2004) fitted a relationship between the vegetation evaporation efficiency and the climate wetness index to published data from catchment studies and proposed this approach for comparing land uses. We fitted this model to the published data for Eucalyptus and Pinus and found that the single parameter of this model did not differ significantly between the two genera (p = 0.48). This was also the case for all parameters of an exponential relationship between evapotranspiration and rainfall (p = 0.589) and a linear relationship between the vegetation evaporation index and rainfall (p = 0.155). These results provide strong evidence that, for a given climate wetness index, the two genera have similar annual water use. The residuals compared to the model of Zhang et al. (2004) were significantly correlated with soil depth for Eucalyptus, but this was not the case for Pinus. For Eucalyptus, the model overestimates the vegetation evaporation efficiency on deep soils and underestimates the vegetation evaporation efficiency on shallow soils
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Clinical and economic impact of ferric carboxymaltose treatment for iron deficiency in patients stabilized following acute heart failure: a multinational study.
OBJECTIVE: To estimate clinical events and evaluate the financial implications of introducing ferric carboxymaltose (FCM) to treat iron deficiency (ID) at discharge in patients hospitalized for acute heart failure (AHF) with left ventricular ejection fraction (LVEF) <50% in the UK, Switzerland and Italy. METHODS: A decision analytic cost-offset model was developed to evaluate the costs associated with introducing FCM for all eligible patients in three countries compared to a world without FCM, over a five-year time horizon. Data from AFFIRM-AHF clinical trial were used to model clinical outcomes, using an established cohort state-transition Markov model. Country-specific prevalence estimates were derived using data from real-world studies to extrapolate number of events and consequent cost totals to the population at risk on a national scale. RESULTS: The cost-offset modeling demonstrated that FCM is projected to be a cost-saving intervention in all three country settings over a five-year time horizon. Savings were driven primarily by reduced hospitalizations and avoided cardiovascular deaths, with net cost savings of -£14,008,238, -CHF25,456,455 and -€105,295,146 incurred to the UK, Switzerland and Italy, respectively. LIMITATIONS: Although AFFIRM-AHF was a multinational trial, efficacy data per country was not sufficiently large to enable country-specific analysis, therefore overall clinical parameters have been assumed to apply to all countries. CONCLUSIONS: This study provides further evidence of the potential cost savings achievable by treating ID with FCM at discharge in patients hospitalized for AHF with LVEF <50%. The value of FCM treatment within the healthcare systems of the UK, Switzerland and Italy was demonstrated even within a limited time frame of one year, with consistent cost savings indicated over a longer term
Ferric carboxymaltose for the treatment of iron deficiency in heart failure: a multinational cost-effectiveness analysis utilising AFFIRM-AHF.
AIMS: Iron deficiency is common in patients with heart failure (HF). In AFFIRM-AHF, ferric carboxymaltose (FCM) reduced the risk of hospitalisations for HF (HHF) and improved quality of life vs. placebo in iron-deficient patients with a recent episode of acute HF. The objective of this study was to estimate the cost-effectiveness of FCM compared with placebo in iron-deficient patients with left ventricular ejection fraction <50%, stabilised after an episode of acute HF, using data from the AFFIRM-AHF trial from Italian, UK, US and Swiss payer perspectives. METHODS AND RESULTS: A lifetime Markov model was built to characterise outcomes in patients according to the AFFIRM-AHF trial. Health states were defined using the 12-item Kansas City Cardiomyopathy Questionnaire (KCCQ-12). Subsequent HHF were incorporated using a negative binomial regression model with cardiovascular and all-cause mortality incorporated via parametric survival analysis. Direct healthcare costs (2020 GBP/USD/EUR/CHF) and utility values were sourced from published literature and AFFIRM-AHF. Modelled outcomes indicated that treatment with FCM was dominant (cost saving with additional health gains) in the UK, USA and Switzerland, and highly cost-effective in Italy [incremental cost-effectiveness ratio (ICER) EUR 1269 per quality-adjusted life-year (QALY)]. Results were driven by reduced costs for HHF events combined with QALY gains of 0.43-0.44, attributable to increased time in higher KCCQ states (representing better functional outcomes). Sensitivity and subgroup analyses demonstrated data robustness, with the ICER remaining dominant or highly cost-effective under a wide range of scenarios, including increasing treatment costs and various patient subgroups, despite a moderate increase in costs for de novo HF and smaller QALY gains for ischaemic aetiology. CONCLUSION: Ferric carboxymaltose is estimated to be a highly cost-effective treatment across countries (Italy, UK, USA and Switzerland) representing different healthcare systems
Impact of ferric carboxymaltose for iron deficiency at discharge after heart failure hospitalization: a European multinational economic evaluation.
AIMS
Iron deficiency (ID) is comorbid in up to 50% patients with heart failure (HF) and exacerbates disease burden. Ferric carboxymaltose (FCM) reduced HF hospitalizations and improved quality of life when used to treat ID at discharge in patients hospitalized for acute HF with left ventricular ejection fraction <50% in the AFFIRM-AHF trial. We quantified the effect of FCM on burden of disease and the wider pharmacoeconomic implications in France, Germany, Poland, Spain and Sweden.
METHODS AND RESULTS
The per country eligible population was calculated, aligning with the 2021 European Society of Cardiology (ESC) HF guidelines and the AFFIRM-AHF trial. Changes in burden of disease with FCM versus standard of care (SoC) were represented by disability-adjusted life years (DALYs), hospitalization episodes and bed days, using AFFIRM-AHF data. A Markov model was adapted to each country to estimate cost-effectiveness and combined with epidemiology data to calculate the impact on healthcare budgets. Between 335 (Sweden) and 13 237 (Germany) DALYs were predicted to be avoided with FCM use annually. Fewer hospitalizations and shorter lengths of stay associated with FCM compared to SoC were projected to result in substantial annual savings in bed days, from 5215 in Sweden to 205 630 in Germany. In all countries, FCM was predicted to be dominant (cost saving with gains in quality-adjusted life years), resulting in net savings to healthcare budgets within 1 year.
CONCLUSIONS
This comprehensive evaluation of FCM therapy highlights the potential benefits that could be realized through implementation of the ESC HF guideline recommendations regarding ID treatment.This work was supported by CSL Vifor, who provided support for model
development, data analysis and medical writing for this study.S
Chikungunya virus infections among travellers returning to Spain, 2008 to 2014
Since the first documented autochthonous transmission of
chikungunya virus in the Caribbean island of Saint Martin in
2013, the infection has been reported within the Caribbean
region as well as North, Central and South America. The risk of
autochthonous transmission of chikungunya virus becoming
established in Spain may be elevated due to the large numbers of
travellers returning to Spain from countries affected by the
2013 epidemic in the Caribbean and South America, as well as the
existence of the Aedes albopictus vector in certain parts of
Spain. We retrospectively analysed the laboratory diagnostic
database of the National Centre for Microbiology, Institute of
Health Carlos III (CNM-ISCIII) from 2008 to 2014. During the
study period, 264 confirmed cases, of 1,371 suspected cases,
were diagnosed at the CNM-ISCIII. In 2014 alone, there were 234
confirmed cases. The highest number of confirmed cases were
reported from the Dominican Republic (n = 136), Venezuela (n =
30) and Haiti (n = 11). Six cases were viraemic in areas of
Spain where the vector is present. This report highlights the
need for integrated active case and vector surveillance in Spain
and other parts of Europe where chikungunya virus may be
introduced by returning travellers
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