Title Promoter Affiliations Abstract "Fate of carbon in Antarctic fjords under increased glacial melt impact" "Ann Vanreusel" Biology "The Western Antarctic Peninsula (WAP) is experiencing drastic changes. The sea ice season has shortened by almost 100 days and 87 % of all glaciers at the WAP are in retreat, with far going impacts on the marine realm. An important aspect of glacial melt on which currently little is known, is the effect on the benthic carbon cycle. Polar fjords are hotspots of carbon burial, which has a climate regulating effect. However, glacial melt disturbance in terms of suspended solids and iceberg scouring can cancel this negative feedback on climate change, by negatively affecting primary production and benthic biomass. In the light of further increases in glacier retreat, it is crucial to understand how the benthic carbon cycle will be altered by these disturbances. In the proposed project, I will study WAP fjords with contrasting glacial melt impacts. I will model the empirical and experimental data gathered during my first FWO post-doc term, to predict benthic secondary production, carbon mineralization and carbon burial in contrasting glacial melt conditions. These results are crucial to forecast whether WAP fjords under increased  climate change impact will function as carbon sources or sinks." "Carbon cycling from a catchment perspective: an integrated approach to terrestrial-aquatic linkages in the Tana River basin (Kenya)" "Filip Meysman" "KU Leuven, Chemistry" "CONTEXT Human activities have resulted in a rapid increase in atmospheric CO2 over the last century, with a profound impact on society and a further rise expected. Consequently, the assessment of the present and future role of terrestrial and aquatic ecosystems as sources or sinks of CO2 is a high-priority area of research [1]. Still, some components of the global carbon (C) cycle are currently not well constrained. One ""blind spot"" concerns the role of inland freshwater systems, which form the interface between terrestrial and marine ecosystems. A recent data compilation suggests a substantial transfer of ~2 Pg C y-1 from the terrestrial biome into freshwater systems, yet, only half of this eventually reaches the ocean [2]. Accordingly, a substantial amount of terrestrial C is processed within freshwater systems, which are a net source of CO2 to the atmosphere (~ half of the oceanic CO2 sink [3]). These cited estimates clearly indicate that freshwater systems function as biogeochemical 'hotspots' on the land-ocean interface, characterized by high process rates [4]. As Masielo [2007, ref 5] points out, improving global C budgets will require a better understanding of the link between soil or catchment characteristics on the terrestrial side, subsequent particle transport and organic matter processing in rivers, and the ultimate C export and burial in the ocean. Hence, the reactive interface between terrestrial and marine ecosystems emerges as a key area for further research. Here, we propose an integrated assessment of carbon processing in the Tana River basin (Kenya), combining targeted data collection with modelling. Basin-wide studies on C transformations are few, and with notable exceptions, our present understanding is to a large extent based on data from a single basin, the Amazon [e.g., 6-7]. Given the scarcity of data on terrestrial-aquatic linkages and our lack of mechanistic insight into the processing and fate of organic matter in freshwater environments, it is uncertain to which extent the existing data can be extrapolated. For example, Richey et al. [2002, ref 8] estimated that CO2 evasion from rivers and wetlands in the central Amazon basin amounts to at least 0.5 Gt C y-1. This flux is an order of magnitude higher than the amount of organic C exported from the river mouth to the ocean, and represents a major component in the overall C budget of the Amazon ecosystem [9]. However, recent findings indicate that other major river basins may act very differently, e.g. Ganges-Brahmaputra [10]. The recognition of terrestrial-aquatic linkages is fundamental to improve our understanding of ongoing and future land use changes. Basin-wide studies on carbon transfer and processing are not only crucial from the perspective of the global C cycle [cfr. 11], but they also have important regional and local implications. In the case of the Tana River basin, intensive deforestation in upland areas results in high sediment delivery to the river system. Increasing demand for energy and water resources (e.g. for existing and planned irrigation schemes) has resulted in the construction of a number of hydroelectric power dams. Such anthropogenic pressures are likely to modify carbon and nutrient cycling in the river, and can have significant cascading effects on downstream ecosystem functioning [e.g., 12]. Organic matter in aquatic systems can originate from old terrestrial C reservoirs (soil or kerogen from rock weathering), recent terrestrial or riparian vegetation, or in-situ (autochthonous) aquatic production. These are characterized by different degrees of reactivity, leading to preferential mineralization, burial, or further transport towards the coastal zone [6, 13]. To disentangle these complex interactions, this proposal combines two complementary types of expertise: state-of-the art isotope measurement techniques and integrated reactive transport modelling. The analytical techniques are focused on specific proxies that trace the origin and processing of different OM sources within the Tana river system. Novel techniques based on the isotopic signatures of specific microbial groups (through selective biomarkers) and DOC provide an unprecedented potential to elucidate complex C flow pathways at different scales [e.g., 14-15]. Similarly, on the modelling side, powerful biogeochemical modelling tools have been developed that simulate organic processing in sediments and aqueous environments [16-17]. Until now, such models do not typically resolve for isotopes (i.e., do not include source information). Here, model formulations will be extended to integrate the extensive proxy data acquired, in order to arrive at a quantitative picture of OM processing within the Tana river basin. Overall, the combination of state-of-the art isotope techniques with reactive transport modelling is novel, and forms a cutting-edge approach to studies on C cycling in natural environments. OBJECTIVES The overall aim of this proposal is to improve our understanding of the biogeochemical functioning of tropical aquatic ecosystems, and to investigate their linkage with the terrestrial environment. The following objectives are pursued: (i) To investigate the impact of catchment land-use, vegetation patterns, and soil characteristics on the origin and biogeochemical processing of different organic matter pools in tropical aquatic systems; (ii) To improve our understanding of the metabolic balance and CO2 source/sink strength of tropical rivers, and to relate this to lateral inputs from the terrestrial biome; (iii) To apply 13C and 15N labelling approaches as an innovative tool to study the organic-mineral association (and hence, preservation) of organic matter along the land-ocean continuum; (iv) To examine the potential of reactive transport modelling to better constrain the source, transport and fate of suspended matter, particulate organic C, and dissolved organic matter along the flowpath of a tropical river." "Hot or Cold? Did changes in volcanic activity influence global temperature evolution throughout geological climate-change events" "Philippe Claeys, Lawrence Percival" "Analytical, Environmental & Geo-Chemistry, Chemistry" "Earth’s history has been marked by frequent episodes of global-scale marine anoxia and organic-matter burial, particularly in the Cretaceous, Devonian, and Silurian. CO2 emissions associated with large igneous provinces are thought to have caused rapid climate warming during the Cretaceous events (e.g., Early Aptian oceanic anoxic event; OAE 1a: ~120 Ma). However, OAE 1a also featured transient cold pulses during the overarching warming, whilst the Devonian and Silurian events (e.g., Frasnian–Famennian crisis: ~372 Ma) were typically characterized by global cooling. It is unclear whether the OAE 1a cooling pulses reflect a volcanic hiatus or enhanced CO2 drawdown via silicate weathering/organic-matter burial. A further question is whether the Devonian and Silurian crises were initiated by volcanism, but with any warming effect totally offset by carbon burial, or had a different trigger to the Cretaceous anoxic events. This proposal employs two widely-used proxies of volcanism (mercury contents and osmium isotopes) to study records of the Cretaceous, Devonian, and Silurian events, focusing on sites that document palaeoclimate trends, enabling direct comparison between changes in volcanic activity and global temperatures. These results will highlight the extent to which volcanism operated during each cooling episode, and thus the importance of volcanic activity in controlling global temperatures at those times." "Tracking the biological control on Si mobilisation in upland ecosystems." "Patrick Meire" "Ecosystem Management" "It is well known that anthropogenic land use changes have strongly influenced the occurrence of biota and soil formation over the last millennia. Land use changes can have a strong effect on the export of carbon, nitrogen and weathering products. The poor knowledge of the biological component in silica biogeochemistry challenges our ability to predict the effects of these land use changes on the silicacycle. Current models for silica export to the ocean still consider it constant. This assumption is now recognized to be invalid, yet our knowledge base is too small to correctly assess human induced variation in diatom productivity and burial rate. This project aims to contribute to filling this fundamental knowledge gap. We want to advance knowledge on how the silica cycle is affected by human activity in a temperateriver basin through a detailed, integrated analysis of silica pools, pathways, fluxes and transformations, thereby using advanced analysis techniques. In this context, the Scheldt basin is extra interesting, as it has high DSi concentrations compared to other systems worldwide, and this is potentially related to high human influence." "Atrial septal defect: evaluation of the therapeutic approach in Belgium through a national database of congenital heart disease." "Werner Budts" "Cardiology, Laboratory of Respiratory Diseases and Thoracic Surgery (BREATHE)" "Atrial septal defect (ASD) represents approximately 10% of all congenital heart diseases (CHD) and is the third most common form of congenital heart defects.  The incidence of CHD in Belgium is 1%, with ASD accounting for 25% of the cases. (Data from the database of CHD UZ Leuven.)  A substantial shunt through the defect from the left to the rightatrium, causing a progressive volume overload of the right heart and pulmonary circulation, may lead to an initially reversible and later irreversible increase in pulmonary vascular resistance (PVR): the origin of pulmonary arterial hypertension (PAH).  This volume and pressure overload of the right heart may lead to heart failure and/or arrhythmias.  Finally, as PVR exceeds systemic resistance, the shunt is reversed (right-to-left shunt) leading to systemic arterial desaturation (and therelated consequences: polyglobulia, hyperuricemia, decreased renal function and abnormal coagulation): the Eisenmenger syndrome (ES).[1] Survival of patients with unrepaired ASDs is thought to be shortened and repair can avoid right ventricular (RV) failure, PAH, thrombo-embolic events and atrial dysrrhythmias. [2]  So, when the defect is discovered early, an ASD is usually closed in childhood, unless the defect is considered not to be clinically significant (< 5mm diameter and no RV volume overload). [3] However, even small ASDs might trigger the development of PAH. Although in some cases surgery remains the only option, percutaneous closure is now considered to be first line-treatment for secundum ASD, as it has similar success rates, lower complication rates and shorter length of hospital stay. [4,5]  Several reports stressed the importance of the implementation of national registries in order to optimize patient care by developing an efficient organizational structure, evidence based treatment protocols, and by assessing research and new treatment modalities.[6,7]  To obtain more structured national data and to create a forum for inter-universitary and inter-academic cooperation regarding adult CHD in Belgium, a national registry of Eisenmenger patients was initiated, which has recently been extended to ASD patients as well. Current guidelines recommend closure of the atrial shunt when substantial (pulmonary to systemic flow > 1,5/1), or for those shunts associated with RV volume overload, in the absence of severe PAH. [8]  Patients considered to have irreversible severe PAH are considered ineligible for shunt closure because of the risk of RV decompensation.  However, Balint et al. reported that transcatheter closure in patients with secundum ASD and moderate or severe PAH can be performed in selected subjects and is associated with good outcomes. [9]  Still, little is known Until which PVR or until what grade of PAH is an ASD still safely repairable? Some authors suspect the existence of masked PAH in patients with ASD.  These are patients with normal right heart pressures at rest, with a pathological increase during exercise.  Theres data supporting the notion that exercise-induced PAH is a mild and clinically relevant phase of the PAH spectrum.  If so, screening and early intervention may prevent progression of pulmonary vascular remodeling. [10]  Oelberg et al. showed that adults with ASD have reduced exercise performance which may be associated with an abnormal increase in pulmonary artery pressure during exercise.[11]  Whats the prevalence of masked PAH in corrected and non-corrected ASD patients?   Although an ASD seems an easilh a corrected ASD have a poorer prognosis than patients in a control group, especially in the presence of PAH, which confers an eightfold increased probability of functional limitations. In the Euroheart survey, PAH was present in 12% of patients with a closed ASD. [12]  Disease-targeting therapy to reduce PAH, such as prostanoids, endothelin receptor antagonists (ERAs) and phosphodiesterase (PDE) inhibitors, has already been used successfully as treatment for patients with PAH, including patients with ES.[13,14] Most studies until now only included patients with severe PAH, while light to moderate PAH is also related to functionality and outcome.[15] Whether it is useful to treat light to moderatePAH after correction of an ASD, in order to have a positive effect on functionality and outcome still needs to be evaluated. [4] If an ASDhasnt been closed, because of the assumption of a too highly elevated PVR, a conservative, non-medical, watchful-waiting approach is usually the treatment of choice. Consequently theres progressive disease and evolution of some patients to a typical ES. This leads to the question: Isit useful to associate selective pulmonary vasodilators in the case of a non-correctable ASD to slow down the increase in PVR and the related clinical complications? To determine surrogate endpoints to answer thesequestions, more insight in baseline characteristics of this patient population is needed. Recent data about clinical evaluation, the role of biochemical parameters, the value of echocardiography, and ergospirometry are scarce in this particular population; in this way, registries might help to identify measurable outcome variables.[16]      General hypothesis, specific aims    1. Evaluation of the usability of the national database of adult CHD, combined withthe epidemiologic description of Eisenmenger patients in Belgium. 2. Epidemiological description all ASD patients registered in Belgium, combined with identification of determinants of outcome, defined as clinical events (cardiac death, development of arrhythmias or PAH, short and long term complications). 3. Evaluation of clinical parameters, echocardiography, bicycle exercise testing, stress echocardiography and biochemical variables in patients with ASD in order to (1) identify reliable endpoints for interventional studies and (2) estimate the prevalence (and determinants) of masked PAH. 4. Evaluation of the effect of selective pulmonary vasodilators in patients with mild to moderate PAH after ASD repair. 5. To evaluate if it is beneficial to treat patients with unrepaired ASD with selective pulmonary vasodilators in order to slow down the increasein PVR and PAH and the related clinical complications. 6. Re-evaluationof Eisenmenger patients in Belgium after 3 years to evaluate determinants of outcome.  Methodology   Patients selection. Patients will be selected through the national registry of adult CHD, developed and maintained by an independent data manager (Alabus Ag, Switzerland).  To be part of the registry, all patients have given signed informed consent. A second informed consent will be obtained in order to participate in one of the prospective studies. These studies will be performed in accordance to the ethical principles as described in the Declaration of Helsinki and after review of the study protocol by the hospitals ethics committee. Study protocol (1) The first two (and sixth) studies have an epidemiological and retrospective design, describing the Eisenmenger and ASD population using the national database on CHD.  Clinical events defined as death of any cause, development of PAH or arrhythmias, hospitalization due to PAH complications and deterioration defined bypredetermined criteria will be considered as the main outcome parameterand evaluated through associative statistical analysis. 2) The third study has a prospective design comparing ASD patients with age and gender matched controls evaluating baseline characteristics of this patient population (clinical signs, echocardiography, bicycle exercise testing, stress echocardiography and biochemical parameters).  This study is necessary, because there is still no evidence in the literature which surrogate endpoints for outcome that can be used in patients with mild to moderate PAH.  (3) The fourth and fifth studies are prospective, randomized, placebo-controlled to evaluate  the effect of specificPAH treatment on surrogate endpoints (determined in the previous study and preferably considering myocardial performance and functional capacity) on residual PAH after ASD repair and on PAH in patients not eligible for ASD repair. This patient population will be more likely to be in NYHA I/II. Hoeper et al. concluded that placebo-controlled for shorter periods of time are still justified in this patient population from an ethical and scientific point of view. As the studies will be too short to determine the effect of vascular remodeling on life expectancy surrogate endpoints will help to evaluate the possible positive effect. Medical treatment with ERAs, PDE inhibitors and prostacyclin analogs has shown to besafe and effective in PAH. Endpoints (1) Endpoints in the retrospective, descriptive studies: Clinical events defined as death of any cause, development of PAH or arrhythmias, hospitalization due to PAH complications and deterioration defined by predetermined criteria will be described.(2) Surrogate endpoints in the prospective, randomized, placebo-controlled studies. (a) Echocardiography Echocardiography is the most widely available imaging test. Disease severity and effect of treatment can be evaluated non-invasively, not only to assess the magnitude of the pathophysiologic adaptations of the heartand pulmonary circulation, but also to detect changes in cardiac structure and function associated with medicaltreatment. Classical two-dimensional, M-Mode and Doppler echocardiography allows us to evaluate (1) RV dysfunction measured by Doppler Tei index of myocardial performance, (2) right and left ventricular dimensions, (3) elevated right atrial pressure as measured by hepatic vein congestion or right atrial area/volume and (4) decreased LV preload, which can bemeasured at baseline and after treatment. M-mode echocardiographic measurements of amplitude of the movement of tricuspid and mitral annulus correlate with right and left ventricular ejection fraction respectively.[17] Tissue Doppler imaging (TDI) might help to assess myocardial velocity (as index of underlying systolic and diastolic function), but might beinfluenced by different loading conditions.[18] Strain, strain rate andspeckle tracking are newer imaging modalities, currently investigated in several studies.  Strain rate describes the rate of change in length calculated as the difference between two velocities normalized to the distance between them.  Strain is the percentage change in lengthduring relaxation/contraction.  These measures are thought to be less load dependent indices of contractile function.[19]  Speckle tracking is an alternative method for quantification of systolic function.  It doesnt have the limitation of angle dependence that TDI-derived strain measurements have. Bicycle stress echocardiography may be helpful to increase the sensitivity of detecting abnormal hemodynamics and for following up the effect of treatment.  This makes it possible toidentify patients with masked PAH by measuring pulmonary pressures during exercise.[20,21] The equipment and expertise needed to conduct echocardiography (including strain/strain-rate, speckle tracking and stress echocardiography) is available in the Laboratory for echocardiography UZ Leuven under supervision of Prof. Dr. Voigt. Echocardiography and off-line analyses would be performed by myself under supervision of Prof. Dr. Voigt.   (b) Cardiopulmonary exercise testing (CPET). Despite RV volume overloading, many patients with ASD do not complain of limited exercise capacity, while assessment with CPET shows a significantly impaired exercise capacity.[22,23]  Measurement of ventilation andpulmonary gas exchange during exercise testing provides an accurate andnon-invasive evaluation of functional capacity and might provide additional information to understand symptoms and underlying pathophysiology.  Several parameters have already been shown of value in the evaluation of patients with idiopathic pulmonary hypertension (iPAH).  Patients with PPH have an inability to adequately increase pulmonary (and therefore systemic) blood flow during exercise resulting in a failure to meet the exercise 02 requirement.  This can be evaluated through peak oxygen consumption (peak vO2), peak O2 pulse and anaerobic threshold.[24,25]  The ventilatory equivalent for CO2 (i.e. the ratio of minute ventilation to carbon dioxide output) is increased in patients with primary pulmonary hypertension and might be a useful parameter to evaluate the efficacy of a drug in improving lung perfusion, even in the short term.[26] CPET can be used to detect a right-to-left shunt during exercise.[27] The equipment and expertise that is needed to efficiently conduct CPET is available in the laboratory for exercise testing UZ Leuven (Prof. Vanhees).  CPET would be performed by an observatory experienced in CPET, analysis of the data will be done by myself.   (c) Biochemistry Patients with patent ASD have significantly elevated brain natriuretic peptide (BNP) levels, which may be an early marker of right ventricular systolic function impairment.  Schoen et al. showed that NT-proBNP is a parameter which correlates to RV dilatation, pulmonary pressure and the amount of interatrial shunting in volume load of the right heart caused by an underlying ASD.  Their role in the assessment of treatment strategies however is still unclear. [28-30]   (d) SF 36 questionnaire The 36 item short form health survey (SF 36) is a commonly used and validated tool to assess health perception in patients with congenital heart disease. [31]   Milestones and timing of the PhD project   (a) First paper (cfr first aim): December 2008, (b) Second paper (cfr second aim): July 2009, (c)Third paper (cfr third aim): July 2010, (d) Fourth paper (cfr fourth aim):  March 2012, (e) Fifth paper (cfr fifth aim): March 2012, (e) Sixth paper (cfr sixth aim): August 2012   Synopsis/conclusion.  PAH treatment in patients with an ASD hasnt been studied until now, because they present mostly with less severe symptoms.  Little is known which endpoints could be used in interventional studies.  Prospective studies to describe baseline characteristics of this patientpopulation are necessary to select useful and reliable endpoints. Using these (surrogate) endpoints randomized, placebo-controlled studies make it possible to address several unanswered research questions in this patient population in order to optimize patient care.   References        1                      Sommer RJ HZ, Rhodes JF: Pathophysiology of congenital heart disease in the adult: Part i: Shunt lesions. Circulation 2008;117:1090-1099.      2                      Konstantinides S GA, Olschewski M, Görnandt L, Roskamm H, Spillner G, Just H, Kasper W.: A comparisonof surgical and medical therapy for atrial septal defect in adults. N Engl J Med 1995;333:469-473.      3                      Warnes CA WR, Bashore TM, ChildJS et al: ACC/AHA 2008 guidelines for the management of adults with congenital heart disease J Am CollCardiol 2008;52:e1-121.      4                      Sharp A MI: Secundum atrial septal defects: Time to close them all? Heart 2008;94:1120-1122.      5                      Du ZD HZ, Kleinmann CS, Silvermandd NH, Larntz K for the Amplatzer Investigators.: Comparison between trancatheter and surgical closure of secundum atrial septal defect in children andadults.  Results of a multicenter nonrandomized trial. J Am Coll Cardiol 2002;39:1836-1844.     6                      Party RotBCSW: Grown-up congenital heart (guch) disease: Current needs and provision of service for adolescents and adults with congenital heart disease in the uk. Heart 2002;88:i1-i14.      7                      Engelfriet P TJ, Kaemmerer H, Gatzoulis MA, Boersma E,Oechslin E, Thaulow E, Popelova J, Moons P, Meijboom F, Daliento L, Hirsch R, Laforest V, Thilen U, Mulder B.: Adherence to clinical guidelinesin the clinical care for adults with congenital heart disease: The euroheart survey on adult congenital heart disease. Eur Heart J 2006;27:737-745.      8                      Attie F RM, Granados N, Zabal C, Buendia A, CalderonJ.: Surgical treatment for secundum atrial septal defects in patients > 40 years old.  A randomized clinical trial. J Am Coll Cardiol2001;38:2035-2042.      9                      Balint OH SA, Haberer K, Tobe L, McLaughlin P, Siu SC, Horlick E, Granton J, Silversides CK.: Outcomes in patients with pulmonary hypertension undergoing percutaneous atrial septal defect closure. Heart 2008;94:1189-1193.      10                    Tolle JJ WA, Van Horn TL, Pappagianopoulos PP, Systrom DM: Exercise-induced pulmonary arterial hypertension. Circulation 2008;118:283-2189.      11                    Oelberg DA MF, Kreisman H, Wolkove N, Langleben D, Small D.: Evaluation of right ventricular systolic pressure during incremental exercise by doppler echocardiography in adults with atrial septal defects. Chest 1998;113:1459-1465.      12                    Engelfriet PMF, Boersma E, Tijssen J, Mulder B.: Repaired and open atrial septal defects type ii in adulthood: An epidemiological study of a large europeancohort. Int J Cardiol 2008;126:379-385.      13                    Rubin LJ BD, Barst RJ, GalieN, Black CM, Keogh A, Pulido T, Frost A, Roux S, Leconte I, Landzberg M, Simonneau G.: Bosentan therapy for pulmonary arterial hypertension. N Engl J Med 2002;346:896-903.      14                    Galie N BM, Gatzoulis MA, Granton J, Bergr RMF, Lauer A, Chiossi E, Landzberg M and for the Bosentan Randomized Trial of Endothelin Antagonist Therapy-5 (BREATHE-5) Investigators.: Bosentan therapy in patients with eisenmenger syndrome: A multicenter, double-blind, randomized, placebo-controlled study. Circulation 2006;114:48-58.      15                    Galiè N RL, Hoeper M, Jansa P, Al-Hiti H, Meyer G, Chiossi E, Kusic-Pajic A, Simonneau G: Treatment of patients with mildly symptomatic pulmonary arterial hypertension with bosentan (early study): A double-blind, randomised controlled trial. Lancet 2008;371:2093-2100.      16                    DavlourosPA NK, Webb G, Gatzoulis MA: The right ventricle in congenital heart disease. 2008 2008;92:i27-i38.      17                    Hanseus KC BG, Brodin LA, Pesonen E: Analysis of atrioventricular plane movements by doppler tissue imaging and m-mode in children with atrial septal defects before and after surgical and device closure. Pediatr Cardiol 2002;23:152-159.      18                    Pauliks LB CK-C,Chang D, Kirby SK, Logan L, DeGroff CG, Boucek MM, Valdez-Cruz LM: Regional myocardial velocities and isovolumic acceleration before and after device closure of atrial septal defects: A color tissue doppler study. Am Heart J 2005;150:294-301.      19                    Eyskens B GJ, Claus P, Boshoff D, Gewillig M, Mertens L: Ultrasonic strain rate and strain imaging of the right ventricle in children before and after percutaneous closure of an atrial septal defect. J Am Soc Echocardiogr 2006;19:994-1000.      20                    Oelberg DA MF,Kreisman H, Wolkove N, Langleben D, Small D: Evaluation of right ventricular systolic pressure during incremental exercise by doppler echocardiography in adults with atrial septal defect. Chest 1998;113:1459-1465.      21                    Grünig E JB, Mereles D, Barth U, Borst MM, Vogt IR, Fischer C, Olschewdski H, Kuecherer HF, Kübler W: Abnormal pulmonary artery pressure response in asymptomatic carriers of primary pulmonary hypertension gene. Circulation 2000;102:1145-1150.      22                    Diller G-P DK, Okonko D, Li W, Babu-Narayan SV, Broberg CS, Johansson B, Bouzas B, Mullen MJ, Poole-Wilson PA, Francis DP, Gatzoulis MA: Exercise intolerance in adult congenital heart disease: Comparative severity, correlates, and prognostic implication. Circulation 2005;112:828-835.      23                    Brochu M-C BJ-F, Dore A, Juneau M, De Guise P, Mercier L-A: Improvement in exercise capacity in asymptomatic andmildly symptomatic adults after atrial septal defect percutaneous closure. Circulation 2002;106:1821-1826.      24                    Palange P WS, Carlsen KH, Casaburi R, Gallagher CG, Gosselink R, O'Donnell DE, Puente-Maestu L, Schols AM, Singh AM, Whipp BJ: Recommendtaions on the use of exercise testing in clinical practice. Eur Respir J 2007;29:185-209.      25                    Sun X-G HJ, Oudiz RJ, Wasserman K: Exercise pathophysiology in patients with primary pulmonary hypertension. Circulation 2001;104:429-435.      26                    Ting H SX-G, Chuang M-L, Lewis DA, Hansen JE, Wasserman K: A noninvasive assessment of pulmonary perfusion abnormality in patients with primary pulmonary hypertension. Chest 2001;119:S24-S32.      27                    Sun X-G HJ, Oudiz RJ, Wasserman K: Gas exchange detection of exercise-induced right-to-left shunt in patients with primary pulmonary hypertension. Circulation 2002;105:54-60.      28                    Schoen SPZT, Kittner T, Braun MU, Fuhrmann J, Shmeisser A, Strasser RH: Nt-probnp correlates with right heart haemodynamic parameters and volumes in patients with atrial septal defects. Eur J Heart Fail 2007;9:660-666.      29                    Trojnarska O SA, Gwizdala A, Oko-Sarnowska Z, Katarzynski S, Siniawski A, Chmara E, Cieslinski A.: Evaluation of exercise capacity with cardiopulmonary exercise testing and type b natriuretic peptide concentrations in adult patients with patent atrial septal defect. Cardiology 2006;106:154-160.      30                    Yap LB AH, Mukerjee D, Coghlan JG, Timms PM: The natriuretic peptides and their role in disorders of right heart dysfunction and pulmonary hypertension. Clin Biochem 2004;37:847-856.      31                    Lane DA LG, Milane TA: Quality of life in adults with congenital heart disease. Heart 2002;88:71-75.    " "CARBonation Tailoring of Eco-efficient Concrete with Hybrid binders (Carb-TECH)" "Nele De Belie" "Department of Structural Engineering and Building Materials" " Researchers and practitioners are continuously in the search for reducing the carbon footprint of concrete. Cementitious materials, included in EU emissions trading system sector, have been targeted by the EU Commission for a 43% cut by 2030 (compared to 2005), but the urgent effective solutions are still lacking. This project aims to achieve eco-efficiency of concrete by proving a novel combination of strategies that allow such a reduction for new concrete. The content of cement, the main contributor to the carbon footprint of concrete, will be reduced by using enhanced hybrid alkali-activated/hydraulic binders containing ground granulated blast furnace slag, fly ash, and other novel precursors. Moreover, recycled concrete aggregates will be used as a partial constituent of optimised granular skeletons, reducing the voids content and binder requirement. Finally, attention will be put on tailoring concrete to convenient carbonation rate, a frequently reported issue of concrete with a high volume of supplementary cementitious materials. For applications with reinforced concrete, high resistance against carbonation to prevent reinforcement corrosion will be targeted, whereas for non-reinforced concrete applications a high carbonation rate without affectation of strength will be achieved for fast CO2 uptake that partially compensates the emission of the material." "Ectomycorrhizal fungi: fueling the belowground carbon cycle" "Jan COLPAERT" "Environmental Biology" "Most trees in temperate and boreal forests live in symbiotic relationship with ectomycorrhizal (EcM) fungi. They receive up to 25% of fixed C from their host plant, similar to the plant investment in plant biomass, making the EcM pathway an equally important energy flow into the soil as plant litter. In relation to the soil carbon balance, the flow of plant energy into ectomycorrhizal fungi has traditionally been considered as a contribution to the soil carbon pool via the production of fungal biomass. On the other hand, there is growing evidence that this flux of easy metabolizable energy induces ('priming') the decomposition of more complex soil organic matter. Soils store a major part of total carbon present on earth. Small deviations in plant productivity (input) and soil respiration (output) can have major effects on the global carbon cycle. Evaluation of land management and environmental effects on the soil carbon balance is dependent on computer models, because direct measurements are difficult due to insensitivity of current analytical methods. But the models used, e.g. for EU legislations and policymaking, do not take into account EcM interactions with soil carbon. The objective of this project is to elucidate and quantify the positive and negative effects of EcM fungi on the soil carbon balance. A combined modeling/experimental approach will be used. Model simulations will be compared with measurements from locations with contrasting EcM and non-EcM vegetation." "Carbonation performance of concrete with recycled aggregates and hybrid binders" "Nele De Belie" "Department of Structural Engineering and Building Materials" "Greenhouse gas emissions associated with concrete production represent about 5% of the total volume of anthropogenic emissions Eco-efficiency of concrete can be achieved through partial replacement of Portland cement by supplementary cementitious materials (SCMs), and by utilizing recycled aggregates The amount of SCMs that can be used in concrete production is limited; however, it can be increased when alkaline additives (referred to as activators) are added to these systems The long term performance of recycled aggregate concrete based on hybrid cements, comprising high volumes of SCM, an alkali-activator and minor fractions of Portland cement, is largely unknown, due to the novelty of these systems Confidence in these concrete types will only be achieved if their durability is evaluated and validated in potentially threatening environmental service conditions This project focuses on the design of eco-efficient concrete based on recycled aggregates and hybrid cements, with the aim to improve the resistance against carbonation in contact with atmospheric CO2, which is a major cause of reinforcement corrosion in concrete structures The final aim is to elucidate the existing relation between the microstructural features of hybrid cement pastes, their response when exposed to CO2, and the consequent changes in the transport properties of concrete, to create novel guidelines for the production of eco-efficient and resilient hybrid concretes" "PEATBURN: Advancing peatland fire modeling with novel information on subsurface fuel moisture from hydrological simulations and satellite observations" "Gabrielle De Lannoy" "Soil and Water Management" "Peatlands are wetlands with a surface layer of organic carbon-rich soil (peat). Even though peatlands are naturally wet most of the time and thus not very prone to fire, droughts in peatlands can prepare the ground for severe wildfires. The interplay of flaming (dominantly biomass) and smoldering (dominantly peat) combustion makes peat fires very persistent. Drying as a result of climate change and human activity leads to more frequent, larger and more severe peatland fires. This will exacerbate global warming due to the instantaneous release of ‘legacy soil carbon’ that accumulated over millennia, and aggravate other adversities for the environment and humankind, such as respiratory diseases with the inhalation of noxious smoke and costs of extensive firefighting.In this project, recent developments in large-scale modeling of peatland hydrology will be combined with emerging techniques from hydrological remote sensing to generate a dynamic peat moisture product of unprecedented quality. This novel information about subsurface fuel moisture conditions, which mainly control the susceptibility to smoldering combustion, will be used for the first time i) to improve fire danger rating systems used in fire management and ii) to reveal unique large-scale insights into links between peat moisture and peatland fires. The demonstration of the benefits of the new peat moisture information will represent a breakthrough in large-scale peatland fire modeling." "Clearing up the Chicxulub Vapor Cloud: Petrographic and geochemical analysis of uniquely preserved impact ejecta and their role in the end-Cretaceous mass extinction" "Philippe Claeys" "Faculty of Sciences and Bioengineering Sciences, Earth System Sciences, Chemistry, Analytical, Environmental & Geo-Chemistry" "The Chicxulub meteorite impact in Mexico was one of the most catastrophic events in the history of life on Earth. This impact happened ~66 million years ago and caused a rapid global climate change and the Cretaceous-Paleogene (K-Pg) mass extinction, marking the end of the dinosaurs. Nearly 40 years of K-Pg research has led to the hypothesis that shock-vaporization of the target rock played a key role in the environmental stress after the impact. However, major questions remain unanswered about the amount and types of products that were injected into the atmosphere, their transport and worldwide deposition, and their climatic and biotic effects. This project is motivated by the recent discovery of two exceptional K-Pg ejecta sites ~3000 km north and south of the Chicxulub crater. In contrast to previous studied ejecta sites, these localities yield uniquely preserved glassy impact spherules. Studying their microtexture and chemical and isotopic compositions, provides additional clues about the contribution of the target lithologies and the meteorite itself. Comparing these sites with proximal and distal ejecta data and new results from Chicxulub core material recently obtained by the IODP-ICDP project enables establishing a new model of vapor plume dynamics and will result in better estimates of the released climate-active gases. This is imperative to understand how the energy release by the impact was transferred to the Earth System and led to the mass extinction."