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Environmental and Financial Evaluation of Passenger Vehicle Technologies in Belgium
Maarten Messagie,Kenneth Lebeau,Thierry Coosemans,Cathy Macharis,Joeri van Mierlo
Sustainability , 2013, DOI: 10.3390/su5125020

Abstract: Vehicles with alternative drive trains are regarded as a promising substitute for conventional cars, considering the growing concern about oil depletion and the environmental impact of our transportation system. However, “clean” technologies will only be viable when they are cost-efficient. In this paper, the environmental impacts and the financial costs of different vehicle technologies are calculated for an average Belgian driver. Environmentally friendly vehicles are compared with conventional petrol and diesel vehicles. The assessments are done from a life cycle perspective. The effect on human health, resources and ecosystems is considered when calculating the environmental impact. The total cost of ownership (TCO) model includes the purchase price, registration and road taxes, insurance, fuel or electricity cost, maintenance, tires replacement, technical control, battery leasing and battery replacement. In the presented analysis different vehicle technologies and fuels are compared (petrol, diesel, hybrid electric vehicles (HEVs), battery electric vehicles (BEVs) and plug-in hybrid electric vehicles (PHEVs)) on their level of environmental impact and cost per kilometer. The analysis shows a lower environmental impact for electric vehicles. However, electric vehicles have a higher total cost of ownership compared to conventional vehicles, even though the fuel operating costs are significantly lower. The purchase cost of electric vehicles is highly linked to the size of the battery pack, and not to the size of the electric vehicle. This explains the relative high cost for the electric city cars and the comparable cost for the medium and premium cars.

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Passive Treatment of Arsenic-Contaminated Dewatering Water Using a Natural Laterite Permeable Reactive Barrier (PRB): Performance Evaluation and Implications for Sustainable Mine Water Management [PDF]
Babacar Diouf, Tidiane Diop, Mor Diop, Maguatte Ndiaye, El Hadji Mamadou Sonko, Thierry Lebeau
Journal of Water Resource and Protection (JWARP) , 2026, DOI: 10.4236/jwarp.2026.189028

Abstract: Arsenic contamination of dewatering water is a major environmental challenge associated with gold mining. Permeable Reactive Barriers (PRBs) offer a sustainable and low-cost passive treatment alternative to conventional technologies. This study evaluated the performance of a natural laterite-based PRB installed at the Sabodala-Massawa gold mine (Senegal) for treating arsenic-contaminated dewatering water. Monitoring was conducted from September 2023 to June 2026 using 49 paired measurements of arsenic concentrations upstream and downstream of the PRB. Influent arsenic concentrations ranged from 46 to 935 μg？L^？¹, while effluent concentrations varied between 0 and 386.5 μg？L^？¹. The PRB achieved a mean arsenic removal efficiency of 82.2 ± 22.2%, with a median of 88.9%, demonstrating consistently high treatment performance despite moderate temporal variability. Most treated water samples complied with the Senegalese discharge standard (300 μg？L^？¹) and frequently met the International Finance Corporation guideline value (100 μg？L^？¹). A moderate positive correlation was observed between influent and effluent arsenic concentrations (r = 0.457), while treatment efficiency improved during the initial months before showing a slight decline after September 2025, suggesting gradual ageing of the reactive material. Sediment analyses further revealed substantial reductions in arsenic (56.6%) and antimony (78.2%) concentrations between the upstream and downstream sections of the PRB, confirming efficient metalloid retention. The treatment performance is mainly attributed to physical filtration, adsorption onto iron oxyhydroxides contained in the lateritic material, and co-precipitation processes. Overall, the results demonstrate that natural laterite is an effective, sustainable, and cost-efficient reactive medium for passive treatment of arsenic-contaminated mine water under tropical conditions. Long-term monitoring is recommended to optimize PRB performance and support the wider application of this technology in mining environments affected by arsenic contamination.

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Genitourinary complications of pelvic and inguinal hernia surgery Les complications uro-génitales de la chirurgie pelvienne et du canal inguinal : au sujet de 15 observations
Koffi Djè, R Lebeau
African Journal of Urology , 2005,

Abstract: Objective: Complications may be encountered during pelvic and inguinal hernia surgery, among them iatrogenic urogenital lesions. The objective of this study is to report on our experience in the management of genitourinary complications of pelvic and inguinal hernia surgery. Patients and Methods: This retrospective study evaluates the genitourinary complications encountered in 15 patients (10 males and 5 females with a mean age of 35.5 years) operated on at our institution between January 1, 1997 and December 31, 2001. They had undergone the following operations: laparotomy for inguinal hernia repair (n=8), volvulus of the sigmoid colon (n=1), rectal occlusive cancer (n=1), uterine rupture (n=1), tubo-ovarian abscess (n=1) and uterine fibroma (n=3). Results: The urinary complications encountered were the following: ureteral injuries (n=7), bladder injuries (n=6) and testicular atrophy (n=2). Six urinary lesions were recognized preoperatively while seven were misdiagnosed and generated postoperative peritonitis. Testicular atrophy occurred after inguinal hernia repair. The treatment modalities applied were uretero-ureteric anastomosis (n=6), ureteric reimplantation (n=1), cystorrhaphy (n=6) and orchidectomy (n=2). There was no morbidity from re-operation. The patient who had undergone emergency laparotomy for occlusion of rectal cancer died on the 12th postoperative day. Conclusion: Prevention of genito-urinary complications of pelvic and inguinal hernia surgery can be best achieved by well-trained surgeons using well-tried operative techniques. Resume Objectif: La chirurgie pelvienne et du canal inguinal expose à des complications parmi lesquelles les lésions iatrogènes urogénitales. Le but de ce travail était de rapporter notre expérience de ces complications. Patients et méthodes: Il s\'agit d\'une étude retrospective des complications uro-génitales survenues au cours de cette chirurgie entre le 1er janvier 1997 le 31 décembre 2001. Elle comprend 15 patients (10 hommes et 5 femmes dont l\'age moyen est de 35,5 ans) opérés en programme opératoire réglé de hernie inguino-scrotale (n=4), de fibrome utérin (n=3) ou en urgence de hernie inguino-scrotale étranglée (n=4), de volvulus du c lon sigmo de (n=1), de cancer du rectum en occlusion (n=1), de rupture utérine (n=1) et de pyoannexe gauche (n=1). Résultats: Les lésions étaient des sections ou plaies urétérales (n=7), des plaies ou em-brochages vésicales (n=6) et des lésions artérielles testiculaires (n=2). Six lésions ont été découvertes immédiatement tandis que neuf ont été méconnues et se sont manifestées par un syndrome péritonéal (n=7) et par une atrophie testiculaire (n=2). Le traitement réalisé était une cystorraphie sur sonde (n=7), une suture urétérale sur catheter (n=6), une réimplantation urétérale (n=1) et une orchidectomie (n=2). La morbidité pour les réinterventions était nulle. Un patient est décédé à J12 post-opératoire - il s\'agit du patient opéré pour cancer du rectum en occlusi

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Spectral Analysis of hypoelliptic random walks
Gilles Lebeau,Laurent Michel
Mathematics , 2013, DOI: 10.1017/S1474748014000073

Abstract: We study the spectral theory of a reversible Markov chain associated to a hypoelliptic random walk on a manifold M. This random walk depends on a parameter h which is roughly the size of each step of the walk. We prove uniform bounds with respect to h on the rate of convergence to equilibrium, and the convergence when h goes to zero to the associated hypoelliptic diffusion.

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Semi-classical analysis of a random walk on a manifold
Gilles Lebeau,Laurent Michel
Mathematics , 2008, DOI: 10.1214/09-AOP483

Abstract: We prove a sharp rate of convergence to stationarity for a natural random walk on a compact Riemannian manifold $(M,g)$. The proof includes a detailed study of the spectral theory of the associated operator.

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Experimental Study of the HUM Control Operator for Linear Waves
Gilles Lebeau,Maelle Nodet
Mathematics , 2009,

Abstract: We consider the problem of the numerical approximation of the linear controllability of waves. All our experiments are done in a bounded domain \Omega of the plane, with Dirichlet boundary conditions and internal control. We use a Galerkin approximation of the optimal control operator of the continuous model, based on the spectral theory of the Laplace operator in \Omega. This allows us to obtain surprisingly good illustrations of the main theoretical results available on the controllability of waves, and to formulate some questions for the future analysis of optimal control theory of waves.

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Injections de Sobolev probabilistes et applications
Nicolas Burq,Gilles Lebeau
Mathematics , 2011,

Abstract: In this article, we give probabilistic versions of Sobolev embeddings on any Riemannian manifold $(M,g)$. More precisely, we prove that for natural probability measures on $L^2(M)$, almost every function belong to all spaces $L^p(M)$, $p<+\infty$. We then give applications to the study of the growth of the $L^p$ norms of spherical harmonics on spheres $\mathbb{S}^d$: we prove (again for natural probability measures) that almost every Hilbert base of $L^2(\mathbb{S}^d)$ made of spherical harmonics has all its elements uniformly bounded in all $L^p(\mathbb{S}^d), p<+\infty$ spaces. We also prove similar results on tori $\mathbb{T}^d$. We give then an application to the study of the decay rate of damped wave equations in a frame-work where the geometric control property on Bardos-Lebeau-Rauch is not satisfied. Assuming that it is violated for a measure 0 set of trajectories, we prove that there exists almost surely a rate. Finally, we conclude with an application to the study of the $H^1$-supercritical wave equation, for which we prove that for almost all initial data, the weak solutions are strong and unique, locally in time.

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Le calcul de la valeur statistique d’une vie humaine
Dionne, Georges,Lebeau, Martin
- , 2010, DOI: https://doi.org/10.7202/1005680ar

Abstract: Notre société fait face à de nombreux risques qui affectent des vies humaines. Les autorités publiques doivent donc déterminer le budget optimal à consacrer à chaque projet visant à diminuer ces risques sociaux. L’analyse avantages-co？ts est un outil très utilisé pour l’évaluation de ces projets. La tache du gouvernement est de mettre en place des projets ou des réglementations qui génèreront des bénéfices supérieurs aux co？ts de leur implantation. Les co？ts sont habituellement assez faciles à déterminer, mais comment évaluer les bénéfices reliés à la sauvegarde de vies humaines? Depuis les années soixante-dix, le nombre d’études réalisées sur la mesure de la valeur statistique d’une vie humaine (VSV) est impressionnant. Plusieurs valeurs ont été estimées, et ce, à l’aide de différentes méthodes. La difficulté des gouvernements à choisir une valeur provient de la grande variabilité dans les résultats obtenus. En effet, les VSV observées varient de 0,5 million de dollars jusqu’à 50 millions de dollars ($？US 2000). L’objectif principal de cet article est d’aider à comprendre d’où vient cette grande variabilité dans les résultats. Nous voulons aussi déterminer quelle valeur nous semble la plus raisonnable

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Examination of Urinary Chlorpyrifos Biomarker Concentrations and Heart Rate in a Sample of US Children and Adolescents [PDF]
Alex LeBeau, Desirae Sutherland, Marie Bourgeois, Jeffrey Driver, Raymond Harbison
Occupational Diseases and Environmental Medicine (ODEM) , 2020, DOI: 10.4236/odem.2020.84013

Abstract: Objective: The purpose of the investigation is to determine if a relationship exists between heart rate and urinary biomarkers of chronic, subacute chlorpyrifos pesticide exposure in youth. Methods: Using 2001-2002 NHANES data, a sample of 1233 children ages 6 - 18 was grouped based on detection status of 3,5,6-trichloropyridinol (TCPy) in urine. Radial pulse and brachial pulse were recorded as measures of heart rate by physicians. T-tests and linear regression analyses were performed to test for associations between TCPy concentrations and heart rate. Results: None of the associations between TCPy levels and heart rate outcomes were found to be significant. Nonsignificant effects in the TCPy-detected groups included a slightly reduced heart rate in girls, as well as a slightly elevated heart rate in boys when compared to the undetected controls. Neither was there any significant observable difference in heart rate due to detection status in the sample overall. Conclusions: At this time, an effect on heart rate attributable to chronic, low-level chlorpyrifos exposure in youth cannot be determined. Children and adolescents detected did not demonstrate a substantial change in pulse measures when compared to controls. It is recommended that subsequent studies examine chlorpyrifos biomarkers as they may relate to other indicators of cardiovascular health.

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Does surgical delay for radical prostatectomy affect patient pathological outcome? A retrospective analysis from a Canadian cohort
Abdullah Alenizi,Assaad El-Hakim,Cedric Lebacle,Emad Rajih,Kelsey Lawson,Kevin C. Zorn,Malek Meskawi,Mansour Alnazari,Marc Zanaty,Mounsif Azizi,Pierre I. Karakiewicz,Pierre-Alain Hueber,Serge Benayoun,Thierry Lebeau
- , 2017, DOI: 10.5489/cuaj.4149

Abstract:

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