References of "2011"
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See detailGobernabilidad desde las agrupaciones usuarias del agua con fines agrícolas en 8 municipios del territorio de la Mancomunidad de Municipios de la cuenca del río Naranjo (MANCUERNA)
Estrada Orozco, Nick Kenner ULg; Mux, Victor

in Tikalia (2011), XXIX(1-2), 37-46

En Guatemala, para alcanzar los Objetivos de desarrollo del Milenio se implemen- tan Programas Conjuntos con el apoyo del Sistema de Naciones Unidas. Existen en la actualidad cinco Programas Conjuntos ... [more ▼]

En Guatemala, para alcanzar los Objetivos de desarrollo del Milenio se implemen- tan Programas Conjuntos con el apoyo del Sistema de Naciones Unidas. Existen en la actualidad cinco Programas Conjuntos apoyando temas de seguridad alimen- taria, construcción de la paz, cambio climático, género y gobernabilidad económi- ca del agua. En el marco del programa conjunto: “Gobernabilidad económica en agua y sanea- miento” se decidió realizar un estudio que permitiera conocer la gobernabilidad en el sector a partir de hacer un inventario de las agrupaciones usuarias de agua con fines agrícolas y conocer algunas de sus características, este estudio contó con la asesoría técnica de la Organización de las Naciones Unidas para la Agricultura y la Alimentación –FAO– y el apoyo en campo de las comunidades asociadas por el agua y el medio ambiente de la cuenca del río Naranjo –CADISNA– en coordina- ción con el Ministerio de Agricultura Ganadería y Alimentación –MAGA– y go- biernos locales. El estudio se realizó en 8 municipios, 3 del departamento de Quetzaltenango y 5 de San Marcos, se identificaron 126 grupos de riego, de ellos, 73 pudieron ser carac- terizados. Se conoció que el 92% de los 73 grupos tiene una junta directiva que vela por el funcionamiento del sistema y la producción se ve diversificada en al menos 14 diferentes hortalizas siendo la principal el cultivo de la Papa. Sin embar- go sólo el 45% paga una tarifa a su grupo y el 60% de los usuarios necesita crédito para poder producir, haciendo uso de al menos 271.99 Lts/seg de agua para fines agrícolas. [less ▲]

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See detailThe Organic Rankine Cycle: Thermodynamics, Applications and Optimization
Quoilin, Sylvain ULg; Lemort, Vincent ULg

in Exergy, Energy system analysis, and Optimization (2011)

New energy conversion technologies are required in order to ensure the production of electricity without generating environmental pollution. Among them, low-grade heat sources or low power heat sources ... [more ▼]

New energy conversion technologies are required in order to ensure the production of electricity without generating environmental pollution. Among them, low-grade heat sources or low power heat sources present an important potential of development. The Organic Rankine Cycle (ORC) is a well known technology since the early 80’s. A large amount of ORC power plants have been built, mainly for geothermal, waste heat recovery and combined heat and power applications. This technology shows a number of advantages over the traditional steam Rankine cycle that make it more profitable for power plants with a limited electrical output power (typically lower than 1 MWe), despite a lower efficiency. The optimization of the ORC is quite different from that of the steam cycle, mainly because of the heat source temperature limitation, and because there is usually no constraint regarding the vapour quality at the end of the expansion. This chapter presents an overview of the current state of the art in the ORC technology and exposes the main target applications. The modelling of such a cycle is described and issues such as fluid selection, optimization or control of the cycle are thoroughly reviewed. [less ▲]

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See detailQuantifying hyporheic exchange at high spatial resolution using natural temperature variations along a first order stream
Westhoff, Martijn ULg; Gooseff, M. N.; Bogaard, T. A. et al

in Water Resources Research (2011), 47

Hyporheic exchange is an important process that underpins stream ecosystem function, and there have been numerous ways to characterize and quantify exchange flow rates and hyporheic zone size. The most ... [more ▼]

Hyporheic exchange is an important process that underpins stream ecosystem function, and there have been numerous ways to characterize and quantify exchange flow rates and hyporheic zone size. The most common approach, using conservative stream tracer experiments and 1-D solute transport modeling, results in oversimplified representations of the system. Here we present a new approach to quantify hyporheic exchange and the size of the hyporheic zone (HZ) using high-resolution temperature measurements and a coupled 1-D transient storage and energy balance model to simulate in-stream water temperatures. Distributed temperature sensing was used to observe in-stream water temperatures with a spatial and temporal resolution of 2 and 3 min, respectively. The hyporheic exchange coefficient (which describes the rate of exchange) and the volume of the HZ were determined to range between 0 and 2.7 × 10−3 s−1 and 0 and 0.032 m3 m−1, respectively, at a spatial resolution of 1–10 m, by simulating a time series of in-stream water temperatures along a 565 m long stretch of a small first-order stream in central Luxembourg. As opposed to conventional stream tracer tests, two advantages of this approach are that exchange parameters can be determined for any stream segment over which data have been collected and that the depth of the HZ can be estimated as well. Although the presented method was tested on a small stream, it has potential for any stream where rapid (in regard to time) temperature change of a few degrees can be obtained. [less ▲]

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See detailMultiparametric observation and analysis of the Sea
Alvera Azcarate, Aïda ULg; Poulain, Pierre-Marie

in Ocean Dynamics (2011)

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See detailA hybrid bioregulatory model of angiogenesis during bone fracture healing
Peiffer, Veronique; Gerisch, Alf; Vandepitte, Dirk et al

in Biomechanics & Modeling in Mechanobiology (2011), 10(3), 383-395

Bone fracture healing is a complex process in which angiogenesis or the development of a blood vessel net work plays a crucial role. In this paper, a mathematicalmodel is presented that simulates the ... [more ▼]

Bone fracture healing is a complex process in which angiogenesis or the development of a blood vessel net work plays a crucial role. In this paper, a mathematicalmodel is presented that simulates the biological aspects of fracture healing including the formation of individual blood vessels. The model consists of partial differential equations, several of which describe the evolution in density of the most important cell types, growth factors, tissues and nutrients. The other equations determine the growth of blood vessels as a result of themovement of leading endothelial (tip) cells. Branching and anastomoses are accounted for in the model. The model is applied to a normal fracture healing case and subjected to a sensitivity analysis. The spatiotemporal evolution of soft tissues and bone, as well as the development of a blood vessel network are corroborated by comparison with experimental data. Moreover, this study shows that the proposed mathematical framework can be a useful tool in the research of impaired healing and the design of treatment strategies. [less ▲]

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See detailTolerability of shortened infliximab infusion times in patients with inflammatory bowel disease: a single center cohort study
Breynaert, C; Ferrante, F; Fidder, H et al

in Acta Gastro-Enterologica Belgica (2011)

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See detailAtlas linguistique de la Wallonie. Tome 17. Famille, vie et relations sociales
Baiwir, Esther ULg

Book published by PULg - Presses universitaires de Liège - Sciences Humaines (2011)

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See detailSynchronization on the circle
Sarlette, Alain ULg; Sepulchre, Rodolphe ULg

in Dubbeldam; Green; Lenstra (Eds.) "The complexity of dynamical systems: a multi-disciplinary perspective" (2011)

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See detailMathematical modeling of cell-cell and cell-matrix adhesion in tissue engineering using continuum models
Geris, Liesbet ULg; Gerisch, A.

in Geffen, A. (Ed.) Cellular and Biomolecular Mechanics and Mechanobiology (2011)

Key factors in the formation of cell aggregates in tissue engineering and other fields are the cell-cell and cell-matrix interactions. Other important factors are culture conditions such as nutrient and ... [more ▼]

Key factors in the formation of cell aggregates in tissue engineering and other fields are the cell-cell and cell-matrix interactions. Other important factors are culture conditions such as nutrient and oxygen supply and the characteristics of the environment (medium versus hydrogel). As mathematical models are increasingly used to investigate biological phenomena, it is important that processes such as cell adhesion are adequately described in the models. Recently a technique was developed to incorporate cell-cell and cell-matrix adhesion in continuum models through the use of non-local terms. In this study we apply this technique to model adhesion in a cell-in-gel culture set-up often found in tissue engineering applications. We briefly describe the biological issues underlying this study and the various modeling techniques used to capture adhesive behaviour. We furthermore elaborate on the numerical techniques that were developed in the course of this study. Finally, we consider a tissue engineering model that describes the spatiotemporal evolution of the concentration of cells, matrix, hydrogel, matrix degrading enzymes and oxygen/nutrients in a cell-in-gel culture system. Sensitivity analyses indicate a clear influence of the different adhesive processes on the final cell and collagen density and distribution, demonstrating the significance of cell adhesion in tissue engineering and the potential of the proposed mathematical technique. [less ▲]

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See detailElectrocoagulation as a tertiary treatment for paper mill wastewater: Removal of non-biodegradable organic pollution and arsenic
Zodi, Salim; Louvet, Jean-Noël ULg; Michon, Clémence et al

in Separation & Purification Technology (2011), 81

The tertiary treatment of paper mill wastewaters was investigated by testing the effect of batch electrocoagulation for 90 min with two parallel iron or aluminum plates at two values of the current ... [more ▼]

The tertiary treatment of paper mill wastewaters was investigated by testing the effect of batch electrocoagulation for 90 min with two parallel iron or aluminum plates at two values of the current density (100 and 150 A/m2). Dissolved organic carbon removal ranged between 24% and 46%, and chemical oxygen demand removal ranged between 32% and 68%. UV–visible spectroscopy showed a reduction of the aromaticity of the treated effluent. The process was also very efficient for the removal of lignin-based pollution, characterized by the fluorescence of humic substances. Arsenic was selected as an example of a non-organic micropollutant and was also satisfactorily removed (from 4 to 0.5 lg/L). The settling characteristics of the sludge obtained after the electrocoagulation treatment were also evaluated. The sludge aptitude to settling is better with Fe electrodes than with Al electrodes. The experimental results obtained in the present study indicate that electrocoagulation treatment can be very effective and was capable of improving the paper mill wastewaters’ quality downstream of the biological treatment. [less ▲]

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See detailTax Evasion, Welfare Fraud, and "The Broken Windows" Effect: An Experiment in Belgium, France and the Netherlands
Lefebvre, Mathieu ULg; Pestieau, Pierre ULg; Riedl, Arno et al

E-print/Working paper (2011)

In a series of experiments conducted in Belgium (Wallonia and Flanders), France and the Netherlands, we compare behavior regarding tax evasion and welfare dodging, with and without information about ... [more ▼]

In a series of experiments conducted in Belgium (Wallonia and Flanders), France and the Netherlands, we compare behavior regarding tax evasion and welfare dodging, with and without information about others’ behavior. Subjects have to decide between a ‘registered’ income, the realization of which will be known to the tax authority for sure, and an ‘unregistered’ income that will only be known with some probability. This unregistered income comes from self-employment in the Tax treatment and from black labor supplementing some unemployment compensation in the Welfare treatment. Subjects have then to decide on whether reporting their income or not, knowing the risk of detection. The results show that (i) individuals evade more in the Welfare treatment than in the Tax treatment; (ii) many subjects choose an option that allows for tax evasion or welfare fraud but report their income honestly anyway; (iii) examples of low compliance tend to increase tax evasion while examples of high compliance exert no influence; (iv) tax evasion is more frequent in France and the Netherlands; Walloons evade taxes less than the Flemish. There is no cross-country difference in welfare dodging. [less ▲]

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See detailPerception and understanding of invasive alien species issues by nature conservation and horticulture professionals in Belgium
Vanderhoeven, Sonia; Piqueray, Julien ULg; Halford, Mathieu ULg et al

in Environmental Management (2011), 47

We conducted a survey to determine how two professional sectors in Belgium, horticulture professionals and nature reserve managers (those directly involved in conservation), view the issues associated ... [more ▼]

We conducted a survey to determine how two professional sectors in Belgium, horticulture professionals and nature reserve managers (those directly involved in conservation), view the issues associated with invasive plant species. We developed and utilized a questionnaire that addressed the themes of awareness, concept and use of language, availability of information, impacts and, finally, control and available solutions. Using co-inertia analyses, we tested to what extent the perception of invasive alien species (IAS) was dependent upon the perception of Nature in general. Only forty-two percent of respondent horticulture professionals and eighty-two percent of nature reserve managers had a general knowledge of IAS. Many individuals in both target groups nonetheless had an accurate understanding of the scientific issues. Our results therefore suggest that the manner in which individuals within the two groups view, or perceive, the IAS issue was more the result of lack of information than simply biased perceptions of target groups. Though IAS perceptions by the two groups diverged, they were on par with how they viewed Nature in general. The descriptions of IAS by participants converged with the ideas and concepts frequently found in the scientific literature. Both managers and horticulture professionals expressed a strong willingness to participate in programs designed to prevent the spread of, and damage caused by, IAS. Despite this, the continued commercial availability of many invasive species highlighted the necessity to use both mandatory and voluntary approaches to reduce their re-introduction and spread. The results of this study provide stakeholders and conservation managers with practical information on which communication and management strategies can be based. [less ▲]

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See detailPancreas preservation for pancreas and islet transplantation: a minireview
SQUIFFLET, Jean-Paul ULg; LeDinh, Hieu; DE ROOVER, Arnaud ULg et al

in Transplantation Proceedings (2011), 43

Pancreas preservation by cold storage using University of Wisconsin solution was the <br />mainstay method used for pancreas transplantation during the past 2 decades. Other <br />solutions, such as HTK ... [more ▼]

Pancreas preservation by cold storage using University of Wisconsin solution was the <br />mainstay method used for pancreas transplantation during the past 2 decades. Other <br />solutions, such as HTK, Celsior, and SCOT 15, could not demonstrate any advantage for <br />short preservation periods. But the advent of clinical islet transplantation and the larger <br />use of controlled non–heart-beating donors have prompted the transplantation community <br />to develop methods for increasing pancreas graft quality while preventing ischemic <br />reperfusion damages. Oxygenation by 1- or 2-layer methods during pancreas preservation, <br />as well as the use of perfluorocarbons, might increase the islet yield. Based on the former <br />methods, there is a renewed interest in machine perfusion and oxygenation in pancreas <br />preservation for pancreas transplantation and islet preparation. [less ▲]

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See detailCouverture de pertes de substance du tibia distal par lambeau pedicule perforant en helice : deux cas cliniques.
Bous, Aurélie ULg; Ronsmans, C.; NIZET, Jean-Luc ULg et al

in Annales de Chirurgie Plastique Esthetique (2011)

Distal lower leg soft tissue defect is frequently a challenge to repair, particularly on the tibial crest. The coverage of this kind of lesion has some limitations because of regional minimal blood supply ... [more ▼]

Distal lower leg soft tissue defect is frequently a challenge to repair, particularly on the tibial crest. The coverage of this kind of lesion has some limitations because of regional minimal blood supply and paucity of local soft-tissue flaps. The perforator pedicled propeller (PPP) method tries to find a new place in lower leg reconstruction in bringing similar tissues at the recipient site and avoiding long and difficult free flap transfer or muscular sacrifice. The authors report on the use of PPP method for a tibial crest exposure after trauma and for a soft tissue defect with osteomyelitis on the tibial crest. [less ▲]

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See detailProfil des vendeurs de viande de chasse et évaluation de la biomasse commercialisée dans les marchés municipaux de Brazzaville, Congo.
Mbete, Roger Albert; Banga-Mboko, Henri; Ngokaka, Christophe et al

in Tropical Conservation Science (2011), 4(2), 203-217

The consumption of wildlife meat is an important source of animal protein for rural and urban population in Congo. A survey on bushmeat trade was undertaken in 21 municipal markets during four weeks, in ... [more ▼]

The consumption of wildlife meat is an important source of animal protein for rural and urban population in Congo. A survey on bushmeat trade was undertaken in 21 municipal markets during four weeks, in Brazzaville. The objective of this study was to define the traders’ profile and to evaluate the quantities of games and meat merchandised on the municipal markets. The study methodology combined two approaches: a quantitative one using a questionnaire as principal tool for collecting data, and a qualitative one associating informal survey methods via individual or group interviews. The results showed that women were the most involved in this trade (52%). Markets trader’s monthly income was estimated at 210,428 (US$420) ± 49,128 (US$98,256) FCFA. On average, the bushmeat traders’ were 39 ± 10 years old and 69% of them attended the two levels of secondary education. During four weeks, 3,711 animal carcasses were recorded on the 21 surveyed markets, representing almost 35,790 kg of biomass. Overall, 35 animal species were identified, including 9 the hunting of which was prohibited. The mammals constituted 93.8% of total number of hunted animals, with three dominant orders as the artiodactyls (49.2%), the rodents (22.6%) and the primates (17.7%), of which the Cephalophus, the Potamochoerus, the Atherurus and the Cercopithecus were the most represented. It was also noticed that trapping, an activity which leads to great losses, becomes very important, followed by be helpful alternatives to meet Congolese demand for bushmeat. For a sustainable management of the Congo’s faunic resources, this study suggests the introduction gun-hunting. The Congo-Ocean Railway and the National Road n°2 were used regularly in the transportation of game, to a 72% level. The district of Niari, Lekoumou, Sangha and Pool were the main sources of supply. At the present time, the meat quantities offered in Brazzaville markets don’t seem to be reduced because hunting areas extend always further, often to the detriment of protected areas. Despite the fact that such business squarely growths and shows evidence of overexploitation, activities promoting game farming and breeding of domestic species, in Brazzaville suburbs, are needed to mitigate the impact of bushmeat trade. [less ▲]

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See detailRés. CE 212.819, Smolcic - 212.989, Vanderlinden - 212.991, Fernandez-Grandjean
Delnoy, Michel ULg

in Aménagement - Environnement (2011), 4

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