Preoperative radiotherapy in rectal cancer : aspects on fractionation and timing of surgery

Neo-adjuvant radiotherapy (RT) in rectal cancer (RC) reduces the risk for local recurrence (LR). The optimal fractionation or time to surgery is not determined. The focus areas of this thesis are different RT-courses and timing of surgery in patients with RC. The Stockholm III trial forms the basis of the studies included in the thesis. Between 1998 – 2013, patients with primarily resectable adenocarcinoma of the rectum were randomly allocated to three different RT-courses. SRT - 5 Gy x 5 and surgery within one week, SRT-delay- 5 Gy x 5 and surgery after 4-8 weeks or LRT-delay - 2 Gy x 25 and surgery after 4-8-weeks. Including centres could choose to randomise patients between three courses or between the two courses with 5 Gy x 5. Primary endpoint was time to LR, secondary end points included distant metastases (DM), survival, tumour regression and adverse events. All patients have been registered in the Swedish ColoRectal Cancer Registry. Paper I. All 840 patients randomised in the Stockholm III trial were analysed after a minimum follow up of 2 years. 357, 355 and 128 patients were allocated to SRT, SRT-delay and LRT-delay respectively. The three armed randomisation was analysed separately and the patients randomised to any of the courses with 5 Gy x 5 were pooled and analysed in a short course RT comparison. About 6 -7 % of the patients with a delay to surgery required hospitalisation between start of RT and surgery due to RT-induced toxicity. In total, 25 patients had a LR within the follow up time, without statistical significant differences between the groups. The cumulative incidence of DM, overall survival (OS) and recurrence free survival (RFS) did not differ between the groups. We found a statistical significant reduction of post-operative complications in SRT-delay compared to SRT (OR 0·61 [95% CI 0·45–0·83] p=0·001). Paper II. The aim this study was to evaluate the post-operative complications in relation to the exact overall treatment time (OTT). Patients were categorized according to OTT and fractionation. Patients that received 5 Gy x 5 were divided into four groups; Group A: 7 days, B: 8-13 days, C: 5-7 weeks, D: 8-13 weeks. Patients that received 2 Gy x 25 were divided in two groups; Group E: 9-11 weeks and F: 12-14 weeks. Main outcome was post-operative complications defined as any-, surgicalor infectious complication. Adjusted odds ratios (any complication) were; A vs. B OR (95 % CI); 0.72 (0.40-1.32) p=0.289, C vs. B 0.50 (0.30-0.84) p=0.009, and D vs. B 0.39 (0.23-0.65) p<0.001. There were no statistical significant differences between group E and F. Paper III. In this study, all available histopathology slides from the resected tumours have been reassessed by one pathologist. Tumour regression was the main outcome and secondary outcomes were histopathological characteristics and the correlation between tumour response and survival. Patients randomised to SRT-delay showed more tumour regression compared to the other arms. A complete pathology graded tumour regression (pCR) was seen in about 10 % of the patients after SRT-delay. Patients with pCR had improved OS and time to recurrence, compared to patients with lower regression grades. Hazard Ratio pCR vs no-pCR: OS: 0.51 (0.26–0.99) p = 0.046, TTR: 0.27 (0.09–0.86) p = 0.027. Paper IV. Long-term follow up of the Stockholm III trial after a minimum follow-up of 5 years. The endpoints from paper I were analysed. The incidence of LR was 11 of 357 (3,1 %), 13 of 355 (3,7) %, 7 of 128 (5,5%) in SRT, SRT-delay and LRT-delay. Incidence of DM was 88 of 257 (24,7%), 82 of 355 (23,1%), 38 of 128 (29,7%). The median OS was 8.14 (7.23-9.98), 10.18 (8.45-11.68) 10,53 (6.95-11.34) years in SRT, SRT-delay and LRT-delay without statistical differences between the groups, log-rank SRT vs. SRT-delay p=0.162 (short course RT comparison), SRT vs. LRT-delay p=0.738 (three armed randomisation). In conclusion, we found no statistical differences between the arms regarding oncological outcomes (LR, DM, OS, RFS). SRT-delay is an alternative with less post-operative complications and higher possibility of pCR compared to SRT. LRT-delay demands more RT-resources without any other obvious gain

Understanding of water resilience in the Anthropocene

Water is indispensable for Earth resilience and sustainable development. The capacity of social-ecological systems to deal with shocks, adapting to changing conditions and transforming in situations of crisis are fundamentally dependent on the functions of water to e.g., regulate the Earth's climate, support biomass production, and supply water resources for human societies. However, massive, inter-connected, human interference involving climate forcing, water withdrawal, dam constructions, and land-use change have significantly disturbed these water functions and induced regime shifts in social-ecological systems. In many cases, changes in core water functions have pushed systems beyond tipping points and led to fundamental shifts in system feedback. Examples of such transgressions, where water has played a critical role, are collapse of aquatic systems beyond water quality and quantity thresholds, desertification due to soil and ecosystem degradation, and tropical forest dieback associated with self-amplifying moisture and carbon feedbacks. Here, we aggregate the volumes and flows of water involved in water functions globally, and review the evidence of freshwater related linear collapse and non-linear tipping points in ecological and social systems through the lens of resilience theory. Based on the literature review, we synthesize the role of water in mediating different types of ecosystem regime shifts, and generalize the process by which life support systems are at risk of collapsing due to loss of water functions. We conclude that water plays a fundamental role in providing social-ecological resilience, and suggest that further research is needed to understand how the erosion of water resilience at local and regional scale may potentially interact, cascade, or amplify through the complex, globally hyper-connected networks of the Anthropocene. © 2018 The Author

Achieving net-zero carbon emissions in construction supply chains - A multidimensional analysis of residential building systems

The construction sector accounts for approximately 25% of global CO2 emissions. In this paper, we provide a multidimensional assessment of the potential for greenhouse gas emissions abatement in relation to the construction of multi-family residential buildings. Different building designs are compared, whereby the study analyzes the potential reductions in greenhouse gas emissions when combining abatement measures with a perspective of the technologies and practices available now, and those that are likely to become available on a timescale up to Year 2045. Further, the assessment analyzes the potential for emissions reductions when applying abatement measures at different points in the supply chain, from primary material production via material composition to the final building structure. The results indicate that the greenhouse gas emissions can be reduced by up to 40% with currently available technologies and practices, with even greater potential reductions of 80% to Year 2030 and 93% to Year 2045

Analys av en statlig utredning – en diskursanalys om hur missbruk, beroende, tvång och individ beskrivs i missbruksutredningen (SOU 2011:35)

The purpose of this study was to analyze from a discourse analytic perspective how The Substance Abuse commissions final report, Improved interventions for substance abuse and dependence - the individual, knowledge and responsibility (SOU 2011:35) (Bättre insatser vid missbruk och beroende – individen, kunskapen och ansvaret), chapter 7, constructs discourses in relation to concepts such as substance abuse, substance addiction and the individual in relation to coercion. The starting point of the study was that through a qualitative approach in the form of critical discourse analysis and discourse theory analyze different concepts. We found three different discourses in the context of SOU 2011:35, chapter 7. The analysis found that a medical discourse has come the farthest in a striving for hegemony in the construct of substance abuse and substance dependence, as well as the individual came to appear as distinct depending on the perception of substance abuse and substance addiction, as well as the measures advocated. A social discourse and penal discourse is less perceptible in SOU 2011:35. This also has implications for what SOU 2011:35 proposes a change to legislation

Ventilationseffektivitet i kontorsmiljö - En jämförelse av deplacerande och omblandande ventilation ur termisk komfort

Today there is a high focus on the energy use when constructing new buildings. This mainly depends on the increased regulations and energy classifications that have been issued. Because of this, studies have shown that mechanical cooling in office environments leads to high energy consumption and service costs. This has led to an increased interest in analyzing if cooling only through ventilation air can reach comparable results. If the analysis could lead to answers where a certain ventilation principle is to prefer to another, this could lead to important conclusions concerning thermal comfort and energy use. This study focuses on performing practical measurements that could tell which of the following ventilation principles, displacement ventilation and mixing ventilation, is most suitable to use in a typical office on a day with medium climate values. The study is based on two earlier investigations regarding the subject and problem. Measurements were made with three different air supplies, two displacement ventilation air supplies and one mixing ventilation air supply. Before the measurements were made a typical office was set up and two measurements of each of the ventilation air supplies were made. During the measurements the ventilation air supply amount and the ventilation air supply temperature were hold constant. This study is mainly distinguished from the other through a better adapted test room and a higher use of varying heat load. The results show that all of the ventilation air supplies reached satisfying thermal conditions with some differences between them. Both displacement ventilation supplies led to a lower air temperature in the zone where people are expected to be than using the mixing ventilation supply. The measured values regarding the experiments with displacement ventilation is found up to 1,2 °C lower than the temperature on corresponding experiments made with mixing ventilation. The experiments show relatively distinct results which affects the energy consumption for cooling. The results indicate that displacement ventilation needs less cooling energy than mixing ventilation to reach the same demands on thermal comfort. In earlier investigations in the subject energy calculations have shown a high saving potential only by increasing the supply air temperature in a room by 1-2 °C. Therefore, displacement ventilation could have a higher supply air temperature thus lowering the energy consumption for cooling the outdoor air while reaching thermal comfort. Keywords: Displacement ventilation, mixing ventilation, temperature efficiency, ventilation efficiency, varying heat load, supply air, extract air

Wave stress and biotic facilitation drive community composition in a marginal hard-bottom ecosystem

Abstract Ecological patterns are inherently scale-dependent and driven by the interplay of abiotic gradients and biotic processes. Despite the fundamental importance of such gradients, there are many gaps in our understanding of how abiotic stress gradients interplay with biotic processes and how these collectively affect species distributions. Using a hierarchical design, we sampled two communities separated by depth along wave exposure and salinity gradients to elucidate how these two gradients affect species composition in habitats formed by the foundation species Mytilus trossulus and Fucus vesiculosus. Specifically, we looked at the impacts of regional salinity and temperature, local wave exposure, and site-dependent facilitation effects on the associated community composition. Wave exposure was the best predictor for species assembly structure, which was also affected by Mytilus biomass and by salinity and water temperature. While the tested variables provided robust explanations for community structure and density, they did not provide conclusive explanations for variation in species richness or evenness. Mytilus biomass had a stronger effect on the associated community with increasing wave exposure at the deeper depth, but the patterns were less obvious at the shallower depth. The latter was also the case for Fucus. These findings comply partly with theoretical predictions suggesting stronger facilitation effects in physically harsh environments. Our results indicate that environmental drivers are the main structuring forces that affect species assembly structure, but also foundation species are important. Thus, predicting changes in species distributions and biodiversity requires the simultaneous consideration of environmental gradients, as well as the structure and composition of foundation species and the interplay between these factors. This work advances our understanding of the processes that modulate species distributions in a marginal marine area and broadens the knowledge of how biological and environmental factors interplay and have an influence on hard-bottom community structure in brackish water seas.peerReviewe

Rootzone storage capacity reveals drought coping strategies along rainforest-savanna transitions

Climate change and deforestation have increased the risk of drought-induced forest-to-savanna transitions across the tropics and subtropics. However, the present understanding of forest-savanna transitions is generally focused on the influence of rainfall and fire regime changes, but does not take into account the adaptability of vegetation to droughts by utilizing subsoil moisture in a quantifiable metric. Using rootzone storage capacity (Sr), which is a novel metric to represent the vegetation's ability to utilize subsoil moisture storage and tree cover (TC), we analyze and quantify the occurrence of these forest-savanna transitions along transects in South America and Africa. We found forest-savanna transition thresholds to occur around a Sr of 550–750 mm for South America and 400–600 mm for Africa in the range of 30%–40% TC. Analysis of empirical and statistical patterns allowed us to classify the ecosystem's adaptability to droughts into four classes of drought coping strategies: lowly water-stressed forest (shallow roots, high TC), moderately water-stressed forest (investing in Sr, high TC), highly water-stressed forest (trade-off between investments in Sr and TC) and savanna-grassland regime (competitive rooting strategy, low TC). The insights from this study are useful for improved understanding of tropical eco-hydrological adaptation, drought coping strategies, and forest ecosystem regime shifts under future climate change

Is wetter better? Exploring agriculturally-relevant rainfall characteristics over four decades in the Sahel

The semi-arid Sahel is a global hotspot for poverty and malnutrition. Rainfed agriculture is the main source of food and income, making the well-being of rural population highly sensitive to rainfall variability. Studies have reported an upward trend in annual precipitation in the Sahel since the drought of the 1970s and early ‘80s, yet farmers have questioned improvements in conditions for agriculture, suggesting that intraseasonal dynamics play a crucial role. Using high-resolution daily precipitation data spanning 1981–2017 and focusing on agriculturally-relevant areas of the Sahel, we re-examined the extent of rainfall increase and investigated whether the increases have been accompanied by changes in two aspects of intraseasonal variability that have relevance for agriculture: rainy season duration and occurrence of prolonged dry spells during vulnerable crop growth stages. We found that annual rainfall increased across 56% of the region, but remained largely the same elsewhere. Rainy season duration increased almost exclusively in areas with upward trends in annual precipitation (23% of them). Association between annual rain and dry spell occurrence was less clear: increasing and decreasing frequencies of false starts (dry spells after first rains) and post-floral dry spells (towards the end of the season) were found to almost equal extent both in areas with positive and those with no significant trend in annual precipitation. Overall, improvements in at least two of the three intraseasonal variables (and no declines in any) were found in 10% of the region, while over a half of the area experienced declines in at least one intraseasonal variable, or no improvement in any. We conclude that rainfall conditions for agriculture have improved overall only in scattered areas across the Sahel since the 1980s, and increased annual rainfall is only weakly, if at all, associated with changes in the agriculturally-relevant intraseasonal rainfall characteristics