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Limiting climate change to 2 °C with a high probability requires reducing cumulative emissions to about 1600 GtCO2 over the 2000–2100 period. This requires unprecedented rates of decarbonization even in the short-run. The availability of the option of net negative emissions, such as bio-energy with carbon capture and storage (BECCS) or reforestation/ afforestation, allows to delay some of these emission reductions. In the paper, we assess the demand and potential for negative emissions in particular from BECCS. Both stylized calculations and model runs show that without the possibility of negative emissions, pathways meeting the 2 °C target with high probability need almost immediate emission reductions or simply become infeasible. The potential for negative emissions is uncertain. We show that negative emissions from BECCS are probably limited to around 0 to 10 GtCO2/year in 2050 and 0 to 20 GtCO2/year in 2100. Estimates on the potential of afforestation options are in the order of 0–4 GtCO2/year. Given the importance and the uncertainty concerning BECCS, we stress the importance of near-term assessments of its availability as today’s decisions has important consequences for climate change mitigation in the long run.

This chapter analyses the policy implications of the climate change challenge. Are current emission reduction pledges made in Copenhagen/Cancun enough to stabilise the climate and limit global average temperature increase to 2 oC? If not, what will the consequences be? What alternative growth pathways could stabilise the global average atmospheric concentration of greenhouse gases (GHG) at 450 ppm, the level which has a 50% chance of keeping the temperature rise to 2 oC? What policies are needed, and what will be the costs and benefits to the economy? How can the world adapt to the warming that is already occurring? To shed light on these questions, this chapter first looks at trends to 2050 in GHG concentration and emissions (including from land use), temperature and precipitation under the Environmental Outlook Baseline scenario of “business-as-usual” (i.e. no new action). It then takes stock of the state of climate policy today. Most countries use a mix of policy instruments, including carbon pricing (carbon taxes, cap-and-trade emissions trading, fossil fuel subsidy reform), other energy efficiency policies, information-based approaches and innovation policies to foster clean technology. The chapter then looks at what further action is needed by comparing different mitigation scenarios against the Baseline. These include various scenarios to stabilise GHG concentrations at 450 ppm and 550 ppm using different technology options, e.g. carbon capture and storage, phasing out nuclear power, and increasing the use of biofuels; linking carbon markets; and various emissions permit allocation rules. The chapter concludes by outlining how limiting global warming will require transformative policies to reconcile short-term action with long-term climate objectives, balancing their costs and benefits. Timely adaptation policies to limit damage by the already changing climate will also be essential.

In order to limit global mean temperature increase, long-term greenhouse gas emissions need to be reduced. This paper discusses the implications of greenhouse gas emission reductions for major Asian regions (China, India, Indonesia, South-East Asia, Japan and Korea) based on results from the IMAGE modelling framework. Energy use in regions and economic sectors is affected differently by ambitious climate policies. We find that the potential for emission reduction varies widely between regions. With respect to technology choices in the power sector, we find major application of CO2 storage in Indonesia and India, whereas Korea and India apply more solar and wind. Projections for Japan include a (debatable) large share of nuclear power. China and, India, and South-East Asia, show a diverse technology choice in the power sector. For the industry sector, we find that the recent rapid growth in China limits the potential for emission reduction in the next decades, assuming that recently built coal-based industry facilities are in use for the next decades. For the residential sector, the model results show that fewer households switch from traditional fuels to modern fuels in GHG mitigation scenarios. With respect to co-benefits, we find lower imports of fossil energy in mitigation scenarios and a clear reduction of air pollutant emissions.

This study compares emission pathways aimed at limiting temperature increase to 2°C under varying constraints. In a first set of pathways, the timing of emission reductions is such that over the 2010–2100 period, assuming full participation from 2013 onwards, mitigation costs are minimized. In a second set of pathways, we set emissions in 2020 at a level based on the pledges of the Copenhagen Accord. In the ‘Copenhagen Potential’ scenario, climate talks result in satisfying conditions linked by countries to their ‘most ambitious’ proposals. Contrasting, in the ‘Copenhagen Current’ scenario, climate talks fall short of satisfying the conditions to move beyond current unilateral pledges. We include scenarios with and without the availability of bio-energy in combination with carbon capture and storage. We find that for a ‘Copenhagen Potential’ scenario, emissions by 2020 are higher (47 GtCO2eq/yr) than for a least-cost pathway for 2°C (43 GtCO2eq/yr with a 40–46 GtCO2eq/yr literature range). In the ‘Copenhagen Potential’ scenario the 2°C target can still be met with a likely chance, although discounted mitigation costs over 2010–2100 could be 10 to 15 % higher, and up to 60 % in the 2040–2050s, than for least-cost pathways. For the ‘Current Copenhagen’ scenario, maintaining an equally low probability of exceeding 2°C becomes infeasible in our model, implying higher costs due to higher climate risks. We conclude that there is some flexibility in terms of 2020 emissions compared to the optimal pathways but this is limited. The 2020 emission level represents a trade-off between short-term emission reductions and long-term dependence on rapid reductions through specific technologies (like negative emission reductions). Higher 2020 emissions lead to higher overall costs and reduced long-term flexibility, both leading to a higher risk of failing to hold warming below 2°C.

Over the past years several studies have explored future land use trends for Europe. This paper presents a comparison of six land use studies for Europe that explore land use changes until 2020/2030. We compared these studies with respect to qualitative as well as quantitative aspects. The qualitative analysis shows that many studies focus on agricultural land uses and therefore draw on detailed agricultural models, while only few include urban developments. The purpose of about half of the studies is to provide land use outlooks, while the other half used scenarios to test the behaviour of scientific models or show their potential applicability. For the quantitative comparison we considered the results of their reference and alternative scenarios. This comparison shows that there is a large difference between the projected results provided by the different outlooks. We even found that alternative scenario outcomes within a single outlook study are more similar than the results of reference scenarios between outlook studies. To a large extent this can be traced back to the differences in initial data sources, data pre-processing and model assumptions. To exclude the impact of differences in initial data, also relative changes were computed. Results from this analysis show a large range of values, which indicates a large uncertainty in the results of land use outlooks. We suggest using all results as the plausibility space for future land use changes. Many studies have kept the values of drivers within a rather limited range, while in reality larger shocks may well be possible.

Endovascular aortic repair (EVAR) is a technique which uses stent grafts to treat aortic aneurysms in patients at risk of aneurysm rupture. Although this technique has been shown to be very successful on the short term, the long term results are less optimistic due to failure of the stent graft. The pulsating blood flow applies stresses and forces to the stent graft, which can cause problems such as breakage, leakage, and migration. Therefore it is of importance to gain more insight into the in vivo motion behavior of these devices. If we know more about the motion patterns in well-behaved stent graft as well as ill-behaving devices, we shall be better able to distinguish between these type of behaviors These insights will enable us to detect stent-related problems and might even be used to predict problems beforehand. Further, these insights will help in designing the next generation stent grafts. Firstly, this work discusses the applicability of ECG-gated CT for measuring the motions of stent grafts in AAA. Secondly, multiple methods to segment the stent graft from these data are discussed. Thirdly, this work proposes a method that uses image registration to apply motion to the segmented stent model

An emergency operation for access related acute critical limb ischemia with signs of infection is described. Inguinal femoral reconstruction was performed with a bifurcated graft constructed from the ipsilateral saphenous vein. Uma operação de emergência relacionada à isquemia aguda com sinais de infecção é descrita. Reconstrução femoral inguinal foi realizada com um enxerto bifurcado feito a partir da veia safena ipsilateral.

Contains fulltext : 88112.pdf (Publisher’s version ) (Closed access) BACKGROUND: Stents are an alternative treatment to carotid endarterectomy for symptomatic carotid stenosis, but previous trials have not established equivalent safety and efficacy. We compared the safety of carotid artery stenting with that of carotid endarterectomy. METHODS: The International Carotid Stenting Study (ICSS) is a multicentre, international, randomised controlled trial with blinded adjudication of outcomes. Patients with recently symptomatic carotid artery stenosis were randomly assigned in a 1:1 ratio to receive carotid artery stenting or carotid endarterectomy. Randomisation was by telephone call or fax to a central computerised service and was stratified by centre with minimisation for sex, age, contralateral occlusion, and side of the randomised artery. Patients and investigators were not masked to treatment assignment. Patients were followed up by independent clinicians not directly involved in delivering the randomised treatment. The primary outcome measure of the trial is the 3-year rate of fatal or disabling stroke in any territory, which has not been analysed yet. The main outcome measure for the interim safety analysis was the 120-day rate of stroke, death, or procedural myocardial infarction. Analysis was by intention to treat (ITT). This study is registered, number ISRCTN25337470. FINDINGS: The trial enrolled 1713 patients (stenting group, n=855; endarterectomy group, n=858). Two patients in the stenting group and one in the endarterectomy group withdrew immediately after randomisation, and were not included in the ITT analysis. Between randomisation and 120 days, there were 34 (Kaplan-Meier estimate 4.0%) events of disabling stroke or death in the stenting group compared with 27 (3.2%) events in the endarterectomy group (hazard ratio [HR] 1.28, 95% CI 0.77-2.11). The incidence of stroke, death, or procedural myocardial infarction was 8.5% in the stenting group compared with 5.2% in the endarterectomy group (72 vs 44 events; HR 1.69, 1.16-2.45, p=0.006). Risks of any stroke (65 vs 35 events; HR 1.92, 1.27-2.89) and all-cause death (19 vs seven events; HR 2.76, 1.16-6.56) were higher in the stenting group than in the endarterectomy group. Three procedural myocardial infarctions were recorded in the stenting group, all of which were fatal, compared with four, all non-fatal, in the endarterectomy group. There was one event of cranial nerve palsy in the stenting group compared with 45 in the endarterectomy group. There were also fewer haematomas of any severity in the stenting group than in the endarterectomy group (31 vs 50 events; p=0.0197). INTERPRETATION: Completion of long-term follow-up is needed to establish the efficacy of carotid artery stenting compared with endarterectomy. In the meantime, carotid endarterectomy should remain the treatment of choice for patients suitable for surgery. FUNDING: Medical Research Council, the Stroke Association, Sanofi-Synthelabo, European Union.

Item does not contain fulltext AIM: Endovascular skills are an integral part of modern-day vascular surgery. The STRESS machine has been developed to test these skills in vascular surgeons. This study aims to define an optimal pass/fail cutoff value for the STRESS test score. METHODS: The STRESS machine consists of a dry glass model of the abdominal aorta and its tributaries with various stenotic lesions, elongations, and tortuosities. A camera and computer software are used to simulate plain fluoroscopy-mode. The test subjects are given two assignments after which two reviewers use a combination of the ICEPS and MRS to produce the final total score; 43 subjects were tested. According to previous endovascular experience, subjects were classified into four groups: novice-low (no experience, less than 11 performed procedures, less than 50 assisted procedures), novice-high (11-25 performed procedures, more than 50 assisted procedures), intermediate (1-10 performed and >11-25 assisted procedures, 11-25 performed and >1-10 assisted procedures or 25-50 performed procedures) and advanced (more than 50 performed procedures). RESULTS: Test-score and noted experience showed a correlation of 0.794. All intermediate and advanced test subjects scored more than 50 points compared to 4 out of 15 novices. CONCLUSION: We demonstrated that it is possible to determine an optimal cut-off value for competence testing with the STRESS machine. 01 april 2010

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This report discusses the attainability of low greenhouse gas concentrations levels based on an analysis using two integrated assessment models (MESSAGE and IMAGE). Model runs were preformed which explored the feasibility of reaching radiative forcing levels in 2100 between 2.6 to 2.9 W/m2 above pre-industrial levels. Such low targets are necessary to limit global mean temperature increase to below 2oC compared to pre-industrial levels with high probability. The analysis examines the attainability of low targets systematically with respect to key uncertainties, including alternative baseline development pathways, availability of different technologies, emissions of bio-energy, and impacts of forestry and land use assumptions. A number of sensitivity tests were carried out to test the robustness of achieving low GHG concentration targets. The results from the two models are discussed in detail comprising energy profiles and emission pathways consistent with such low stabilization targets.

Item does not contain fulltext OBJECTIVE: Determining possible differences in living donor nephrectomy procedures: laparoscopy against mini-incision concerning discomfort to the donor and the maintenance of good graft function. DESIGN: Blind randomized study. METHOD: In two university medical centres, one hundred living kidney donors were randomly assigned to either total laparoscopic donor nephrectomy or mini-incision muscle-splitting open donor nephrectomy. Primary outcome was physical fatigue measured with the 'Multidimensional Fatigue Inventory' (MFI-20) during one-year follow-up. Secondary outcomes were physical function measured with the 'Short form-36' questionnaire, postoperative hospital stay, amount of pain, operating times and graft and patient survival. RESULTS: Donors who underwent laparoscopy experienced less fatigue (difference: -1.3; 95% CI: -2.4 - (-0.1)) and physical function was better (difference: 6.2; 95% CI: 2.0-10.3) during one-year follow-up. Those donors who underwent laparoscopy required less morphine (16 mg versus 25 mg; p = 0.005) and the duration of hospital stay was shorter (3 versus 4 days; p = 0.003). The laparoscopic procedure resulted in a longer operation time (221 versus 164 min; p < 0.001) a longer first warm ischaemia time (6 versus 3 min; p < 0.001) and less blood loss (100 versus 240 ml; p < 0.001). Recipient renal function and one-year graft survival rates did not differ. The number of preoperative and postoperative complications did not differ significantly between both surgery techniques. Conversions did not occur. CONCLUSION: Donor nephrectomy through laparoscopy led to less fatigue and a better quality of life compared with the open procedure. The safety factors for donors and recipients were comparable for both techniques. Laparoscopic donor nephrectomy is therefore the better surgical choice for kidney donor programmes with living donors.