Meaningful occupation as a fundamental principle of health and citizenship

Introduction : Occupational therapists are concerned with fostering abilities and opportunities towards meaningful participation. This aim is conceived in health terms, but implies that health is connected to enacting citizenship, since participation goals are social, transactional and depend on interaction and reciprocal exchange. Objectives: To present a critical discussion of the significance of occupation for health and transformative citizenship. Approach Restriction in participation is also a restriction of citizenship. Practice-based vignettes will serve as examples of how dis-citizenship is generated through marginalisation with negative impacts on health outcomes. Secondly, we will frame exercising citizenship as social participation. This approach of participatory citizenship brings forth the potential of social transformation both individually and collectively based on new collective understandings and mutual recognition. Practice implications Approaching citizenship and health as interrelated and embodied rather than abstract, takes into account the ways in which social and cultural backgrounds as well as material circumstances affect people's lives as citizens. Health conditions are generated or maintained by social conditions such as poverty and limited access to resources and affected by cultural factors such as difference. The implication of critical occupation-based practise is that it offers a possibility to question and challenge these limitations and create particular spaces of action where in everyday life people negotiate rights and possibilities, belonging and participation. Conclusion Citizenship as an occupational practice of participation has valuable potential as the basis for the understanding of processes of participation and health as for the promotion of social transformation and more inclusive communitie

Étude de la dégradation de la sulfaclozine par les radicaux OH• et SO4•– et évaluation de l'influence des principaux constituants des eaux sur ces dégradations

In this work, we studied the degradation of the antibiotic sulfaclozine in aqueous solutions by photocatalysis (on TiO2 suspensions) as well as by persulfate ions. The use of specific inhibitors (KI and alcohols) allowed us to understand the intervention of each of the reactive species (electrons, holes, radicals •OH) in the degradation of sulfaclozine. In addition, the identification of the by-products by LC-MS / MS and the monitoring of their appearance and disappearance kinetics, allowed us to propose a photocatalytic degradation mechanism involving TiO2 holes, •OH radicals, electrons, and O2•– radicals. We also evaluated several methods for persulfate activation (UV, sunlight, UV / TiO2 and Fe (II)) to generate SO4•–. We have shown that at pH 7, the system having the highest efficiency, regardless of persulfate concentration, was the UV/TiO2/K2S2O8 system. The use of specific inhibitors of •OH and SO4•– radicals showed that pH has a significant effect on the role of each of these radicals in the sulfaclozine degradation. Moreover, the reaction rate constants of sulfaclozine with •OH radicals and with SO4•– radicals were determined and close values were found (?109 M-1s-1). We also studied the effect of the main water constituents on the degradation of sulfaclozine in the following three systems: UV/TiO2, UV/TiO2/K2S2O8 and UV/K2S2O8. This study showed that bicarbonate and phosphate accelerated the photocatalytic degradation of sulfaclozine while no effect was observed in the UV/K2S2O8 system. Regarding chloride and nitrate ions, we obtained an enhancement in sulfaclozine adsorption on the surface of TiO2 but no significant enhancement of the degradation rate was observedDans ce travail, nous avons étudié la dégradation de la sulfaclozine, un antibiotique, dans des solutions aqueuses par photocatalyse (TiO2 en suspensions) ainsi que par oxydation par les ions persulfate. L'utilisation d'inhibiteurs spécifiques (KI et alcools) nous a permis de comprendre l'intervention de chacune des espèces réactives (électrons, trous, radicaux •OH) dans la dégradation de la sulfaclozine. En outre, l'identifications des produits de dégradation par LC-MS/MS et le suivi de leur cinétique d'apparition et de disparition avec et sans alcool nous a permis de proposer un mécanisme de dégradation photocatalytique faisant intervenir les trous, les radicaux •OH, les électrons, et les radicaux O2•–. Nous avons également évalués plusieurs méthodes d'activation du persulfate (UV, irradiation solaire, UV/TiO2 et Fe(II)) afin de générer des radicaux SO4•– pour dégrader la sulfaclozine. Nous avons montré qu'à pH 7, le système présentant la plus grande efficacité quelque soit la concentration de persulfate, était le système UV/TiO2/K2S2O8. L'utilisation des inhibiteurs spécifiques des radicaux •OH et SO4•– a permis de constater que le pH a un effet important sur le rôle de chacun de ces radicaux dans la dégradation de la sulfaclozine. Les constantes de vitesse de la réaction de la sulfaclozine avec les radicaux •OH et SO4•– ont été déterminées et des valeurs proches ont été trouvées (?109 M-1s-1). Nous avons également étudié l'effet des principaux ions constituants de l'eau sur la dégradation de la sulfaclozine dans les trois systèmes suivants: UV/TiO2, UV/TiO2/K2S2O8 et UV/K2S2O8. Cette étude a montré que les bicarbonates et les phosphates accélèrent la dégradation photocatalytique alors qu'aucun effet n'a été observé dans le système UV/K2S2O8. En ce qui concerne les ions chlorures et nitrates nous avons montré qu'ils augmentaient l'adsorption de la sulfaclozine à la surface de TiO2 mais n'accéléraient pas significativement la réaction de dégradatio

Étude de la dégradation de la sulfaclozine par les radicaux OH• et SO4•– et évaluation de l'influence des principaux constituants des eaux sur ces dégradations

In this work, we studied the degradation of the antibiotic sulfaclozine in aqueous solutions by photocatalysis (on TiO2 suspensions) as well as by persulfate ions. The use of specific inhibitors (KI and alcohols) allowed us to understand the intervention of each of the reactive species (electrons, holes, radicals •OH) in the degradation of sulfaclozine. In addition, the identification of the by-products by LC-MS / MS and the monitoring of their appearance and disappearance kinetics, allowed us to propose a photocatalytic degradation mechanism involving TiO2 holes, •OH radicals, electrons, and O2•– radicals. We also evaluated several methods for persulfate activation (UV, sunlight, UV / TiO2 and Fe (II)) to generate SO4•–. We have shown that at pH 7, the system having the highest efficiency, regardless of persulfate concentration, was the UV/TiO2/K2S2O8 system. The use of specific inhibitors of •OH and SO4•– radicals showed that pH has a significant effect on the role of each of these radicals in the sulfaclozine degradation. Moreover, the reaction rate constants of sulfaclozine with •OH radicals and with SO4•– radicals were determined and close values were found (?109 M-1s-1). We also studied the effect of the main water constituents on the degradation of sulfaclozine in the following three systems: UV/TiO2, UV/TiO2/K2S2O8 and UV/K2S2O8. This study showed that bicarbonate and phosphate accelerated the photocatalytic degradation of sulfaclozine while no effect was observed in the UV/K2S2O8 system. Regarding chloride and nitrate ions, we obtained an enhancement in sulfaclozine adsorption on the surface of TiO2 but no significant enhancement of the degradation rate was observedDans ce travail, nous avons étudié la dégradation de la sulfaclozine, un antibiotique, dans des solutions aqueuses par photocatalyse (TiO2 en suspensions) ainsi que par oxydation par les ions persulfate. L'utilisation d'inhibiteurs spécifiques (KI et alcools) nous a permis de comprendre l'intervention de chacune des espèces réactives (électrons, trous, radicaux •OH) dans la dégradation de la sulfaclozine. En outre, l'identifications des produits de dégradation par LC-MS/MS et le suivi de leur cinétique d'apparition et de disparition avec et sans alcool nous a permis de proposer un mécanisme de dégradation photocatalytique faisant intervenir les trous, les radicaux •OH, les électrons, et les radicaux O2•–. Nous avons également évalués plusieurs méthodes d'activation du persulfate (UV, irradiation solaire, UV/TiO2 et Fe(II)) afin de générer des radicaux SO4•– pour dégrader la sulfaclozine. Nous avons montré qu'à pH 7, le système présentant la plus grande efficacité quelque soit la concentration de persulfate, était le système UV/TiO2/K2S2O8. L'utilisation des inhibiteurs spécifiques des radicaux •OH et SO4•– a permis de constater que le pH a un effet important sur le rôle de chacun de ces radicaux dans la dégradation de la sulfaclozine. Les constantes de vitesse de la réaction de la sulfaclozine avec les radicaux •OH et SO4•– ont été déterminées et des valeurs proches ont été trouvées (?109 M-1s-1). Nous avons également étudié l'effet des principaux ions constituants de l'eau sur la dégradation de la sulfaclozine dans les trois systèmes suivants: UV/TiO2, UV/TiO2/K2S2O8 et UV/K2S2O8. Cette étude a montré que les bicarbonates et les phosphates accélèrent la dégradation photocatalytique alors qu'aucun effet n'a été observé dans le système UV/K2S2O8. En ce qui concerne les ions chlorures et nitrates nous avons montré qu'ils augmentaient l'adsorption de la sulfaclozine à la surface de TiO2 mais n'accéléraient pas significativement la réaction de dégradatio

Study of sulfaclozine degradation by OH• and SO4•– radicals and evaluation of the influence of the main water constituents on these degradations

Dans ce travail, nous avons étudié la dégradation de la sulfaclozine, un antibiotique, dans des solutions aqueuses par photocatalyse (TiO2 en suspensions) ainsi que par oxydation par les ions persulfate. L'utilisation d'inhibiteurs spécifiques (KI et alcools) nous a permis de comprendre l'intervention de chacune des espèces réactives (électrons, trous, radicaux •OH) dans la dégradation de la sulfaclozine. En outre, l'identifications des produits de dégradation par LC-MS/MS et le suivi de leur cinétique d'apparition et de disparition avec et sans alcool nous a permis de proposer un mécanisme de dégradation photocatalytique faisant intervenir les trous, les radicaux •OH, les électrons, et les radicaux O2•–. Nous avons également évalués plusieurs méthodes d'activation du persulfate (UV, irradiation solaire, UV/TiO2 et Fe(II)) afin de générer des radicaux SO4•– pour dégrader la sulfaclozine. Nous avons montré qu'à pH 7, le système présentant la plus grande efficacité quelque soit la concentration de persulfate, était le système UV/TiO2/K2S2O8. L'utilisation des inhibiteurs spécifiques des radicaux •OH et SO4•– a permis de constater que le pH a un effet important sur le rôle de chacun de ces radicaux dans la dégradation de la sulfaclozine. Les constantes de vitesse de la réaction de la sulfaclozine avec les radicaux •OH et SO4•– ont été déterminées et des valeurs proches ont été trouvées (?109 M-1s-1). Nous avons également étudié l'effet des principaux ions constituants de l'eau sur la dégradation de la sulfaclozine dans les trois systèmes suivants: UV/TiO2, UV/TiO2/K2S2O8 et UV/K2S2O8. Cette étude a montré que les bicarbonates et les phosphates accélèrent la dégradation photocatalytique alors qu'aucun effet n'a été observé dans le système UV/K2S2O8. En ce qui concerne les ions chlorures et nitrates nous avons montré qu'ils augmentaient l'adsorption de la sulfaclozine à la surface de TiO2 mais n'accéléraient pas significativement la réaction de dégradationIn this work, we studied the degradation of the antibiotic sulfaclozine in aqueous solutions by photocatalysis (on TiO2 suspensions) as well as by persulfate ions. The use of specific inhibitors (KI and alcohols) allowed us to understand the intervention of each of the reactive species (electrons, holes, radicals •OH) in the degradation of sulfaclozine. In addition, the identification of the by-products by LC-MS / MS and the monitoring of their appearance and disappearance kinetics, allowed us to propose a photocatalytic degradation mechanism involving TiO2 holes, •OH radicals, electrons, and O2•– radicals. We also evaluated several methods for persulfate activation (UV, sunlight, UV / TiO2 and Fe (II)) to generate SO4•–. We have shown that at pH 7, the system having the highest efficiency, regardless of persulfate concentration, was the UV/TiO2/K2S2O8 system. The use of specific inhibitors of •OH and SO4•– radicals showed that pH has a significant effect on the role of each of these radicals in the sulfaclozine degradation. Moreover, the reaction rate constants of sulfaclozine with •OH radicals and with SO4•– radicals were determined and close values were found (?109 M-1s-1). We also studied the effect of the main water constituents on the degradation of sulfaclozine in the following three systems: UV/TiO2, UV/TiO2/K2S2O8 and UV/K2S2O8. This study showed that bicarbonate and phosphate accelerated the photocatalytic degradation of sulfaclozine while no effect was observed in the UV/K2S2O8 system. Regarding chloride and nitrate ions, we obtained an enhancement in sulfaclozine adsorption on the surface of TiO2 but no significant enhancement of the degradation rate was observe

Study of sulfaclozine degradation by OH• and SO4•– radicals and evaluation of the influence of the main water constituents on these degradations

Dans ce travail, nous avons étudié la dégradation de la sulfaclozine, un antibiotique, dans des solutions aqueuses par photocatalyse (TiO2 en suspensions) ainsi que par oxydation par les ions persulfate. L'utilisation d'inhibiteurs spécifiques (KI et alcools) nous a permis de comprendre l'intervention de chacune des espèces réactives (électrons, trous, radicaux •OH) dans la dégradation de la sulfaclozine. En outre, l'identifications des produits de dégradation par LC-MS/MS et le suivi de leur cinétique d'apparition et de disparition avec et sans alcool nous a permis de proposer un mécanisme de dégradation photocatalytique faisant intervenir les trous, les radicaux •OH, les électrons, et les radicaux O2•–. Nous avons également évalués plusieurs méthodes d'activation du persulfate (UV, irradiation solaire, UV/TiO2 et Fe(II)) afin de générer des radicaux SO4•– pour dégrader la sulfaclozine. Nous avons montré qu'à pH 7, le système présentant la plus grande efficacité quelque soit la concentration de persulfate, était le système UV/TiO2/K2S2O8. L'utilisation des inhibiteurs spécifiques des radicaux •OH et SO4•– a permis de constater que le pH a un effet important sur le rôle de chacun de ces radicaux dans la dégradation de la sulfaclozine. Les constantes de vitesse de la réaction de la sulfaclozine avec les radicaux •OH et SO4•– ont été déterminées et des valeurs proches ont été trouvées (?109 M-1s-1). Nous avons également étudié l'effet des principaux ions constituants de l'eau sur la dégradation de la sulfaclozine dans les trois systèmes suivants: UV/TiO2, UV/TiO2/K2S2O8 et UV/K2S2O8. Cette étude a montré que les bicarbonates et les phosphates accélèrent la dégradation photocatalytique alors qu'aucun effet n'a été observé dans le système UV/K2S2O8. En ce qui concerne les ions chlorures et nitrates nous avons montré qu'ils augmentaient l'adsorption de la sulfaclozine à la surface de TiO2 mais n'accéléraient pas significativement la réaction de dégradationIn this work, we studied the degradation of the antibiotic sulfaclozine in aqueous solutions by photocatalysis (on TiO2 suspensions) as well as by persulfate ions. The use of specific inhibitors (KI and alcohols) allowed us to understand the intervention of each of the reactive species (electrons, holes, radicals •OH) in the degradation of sulfaclozine. In addition, the identification of the by-products by LC-MS / MS and the monitoring of their appearance and disappearance kinetics, allowed us to propose a photocatalytic degradation mechanism involving TiO2 holes, •OH radicals, electrons, and O2•– radicals. We also evaluated several methods for persulfate activation (UV, sunlight, UV / TiO2 and Fe (II)) to generate SO4•–. We have shown that at pH 7, the system having the highest efficiency, regardless of persulfate concentration, was the UV/TiO2/K2S2O8 system. The use of specific inhibitors of •OH and SO4•– radicals showed that pH has a significant effect on the role of each of these radicals in the sulfaclozine degradation. Moreover, the reaction rate constants of sulfaclozine with •OH radicals and with SO4•– radicals were determined and close values were found (?109 M-1s-1). We also studied the effect of the main water constituents on the degradation of sulfaclozine in the following three systems: UV/TiO2, UV/TiO2/K2S2O8 and UV/K2S2O8. This study showed that bicarbonate and phosphate accelerated the photocatalytic degradation of sulfaclozine while no effect was observed in the UV/K2S2O8 system. Regarding chloride and nitrate ions, we obtained an enhancement in sulfaclozine adsorption on the surface of TiO2 but no significant enhancement of the degradation rate was observe

determination of sulfaclozine degradation pathway on tio2 suspensions based on the role of different ros.

SSCI-VIDE+ATARI+LIS:JMC:CFE:LFIInternational audienceThe photocatalytic removal of the antibiotic sulfaclozine (SCL) in aqueous suspensions of TiO2 under UV light was investigated and a complete degradation of 88 µM of sulfaclozine was obtained after 60 min. The addition of reactive oxygen species (ROS) scavengers (isopropanol, methanol and KI) at different concentrations allowed us to understand the assessment of the different ROSs in sulfaclozine degradation.The rate constant of the reaction between sulfaclozine and â¢OH radicals was determined by a competitive kinetic method and a value of (7.2Ã109 M-1 s-1) was found.HPLC/DAD and LC-MS/MS were used to follow the kinetics of appearance and disappearance of sulfaclozine as well as its intermediates. Twelve main photoproducts were identified from the photocatalytic degradation of sulfaclozine on TiO2 suspensions by using LC-MS/MS. The comparison of the evolution of these intermediates with and without the addition of methanol showed that the quantity of 8 intermediates was decreased in the presence of methanol, for three of them the same amount was obtained while an increase was observed for one of them. Based on the identified intermediates, and the effect of ROS scavengers, a tentative degradation pathway for the photocatalytic degradation of sulfaclozine was proposed. In addition, total organic carbon (TOC) was examined

determination of sulfaclozine degradation pathway on tio2 suspensions based on the role of different ros.

SSCI-VIDE+ATARI+LIS:JMC:CFE:LFIInternational audienceThe photocatalytic removal of the antibiotic sulfaclozine (SCL) in aqueous suspensions of TiO2 under UV light was investigated and a complete degradation of 88 µM of sulfaclozine was obtained after 60 min. The addition of reactive oxygen species (ROS) scavengers (isopropanol, methanol and KI) at different concentrations allowed us to understand the assessment of the different ROSs in sulfaclozine degradation.The rate constant of the reaction between sulfaclozine and â¢OH radicals was determined by a competitive kinetic method and a value of (7.2Ã109 M-1 s-1) was found.HPLC/DAD and LC-MS/MS were used to follow the kinetics of appearance and disappearance of sulfaclozine as well as its intermediates. Twelve main photoproducts were identified from the photocatalytic degradation of sulfaclozine on TiO2 suspensions by using LC-MS/MS. The comparison of the evolution of these intermediates with and without the addition of methanol showed that the quantity of 8 intermediates was decreased in the presence of methanol, for three of them the same amount was obtained while an increase was observed for one of them. Based on the identified intermediates, and the effect of ROS scavengers, a tentative degradation pathway for the photocatalytic degradation of sulfaclozine was proposed. In addition, total organic carbon (TOC) was examined

photocatalysis for the removal of environmental pollutants from water: a reflection about its efficiency

SSCI-VIDE+ATARI+CFE:MFS:LIS:LFI:LZO:JMCInternational audienceOver the last few years there has been a growing concern over the increasing concentration of micro-pollutants originating from a great variety of sources including pharmaceutical, chemical engineering and personal care product industries, in rivers, lakes, soil and groundwater [1,2]. As most of the micro-pollutants are rather polar and biologically active compounds, they are not biodegradable and do not adsorb easily onto the sludge, which makes them difficult or impossible to eliminate from classical wastewater treatment plants (WWTP). It is hypothesized that wastewater is one of the most important point sources for micro-pollutants. The consequences are particularly worrying in aquatic organisms as even at very low concentrations, micro-pollutants can affect the growth and reproduction of fish and amphibians, damage the nervous systems of aquatic organisms or inhibit algal photosynthesis. The presence of micro-pollutants also endangers the reuse of treated wastewater, a generally proposed solution to achieve a sustainable water cycle management [3,4].The need for treatment technologies that can provide safe treated effluents led to the development of effective tertiary treatment to ensure a safe use for reclaimed wastewater [4].The available technologies include Advanced Oxidation Processes (AOP) such as ozone, ozone/H2O2, UV/H2O2, Fenton, photo-Fenton etc in which the generation of highly reactive hydroxyl radicals are responsible of the degradation of most of organic compounds. Photocatalysis belongs to these processes. The photocatalytic degradation uses light radiation of near UV (300-400 nm) as an energy source capable of activating semiconductors such as titanium dioxide TiO2, known for its high efficiency. It has been shown in the literature that TiO2 could degrade and mineralize almost all kind of organic compounds. However, the development of photocatalysis for the treatment of wastewaters remains limited by the presence of background components such as natural organic matter carbonates ions etc which slow down the degradation of the target micro-pollutants.In this context, the current presentation will begin with results concerning the photocatalytic degradation both in river water and in Ultra-pure water of a model molecule [5]. Explanations about the lowest efficiency obtained in river water will be given and compared with the ones coming from the literature. For example effects such as a competitive adsorption between the pollutant and the background components, the scavenging of hydroxyl radicals by background components, the inner filter played by humic substances or the formation of TiO2 aggregate in presence of alkalinity will be discussed.In the last part, a reflection about the role played by bicarbonate ions on the photocatalytic efficiency will be presented. In particularly if it is known that usually bicarbonates ions slow down the photocatalytic efficiency, in some cases no effect or an increase can be observed which will be discussed

Towards a better understanding of the reactive species involved in the photocatalytic degradation of sulfaclozine

SSCI-VIDE+ATARI+LIS:CFE:LFI:JMCInternational audienceThe photocatalytic degradation of sulfaclozine on TiO2 suspensions underUV light was investigated and a complete degradation of 88 mu M ofsulfaclozine was obtained after 60 min. The addition of isopropanol (500mM), methanol (500 mM), and ICI (10 mM) to the system inhibited thedegradation of sulfaclozine c.a 60%, 85% and 95% respectively, whichallowed us to conclude that (OH)-O-center dot radicals, valence-bandholes and electrons could intervene in the degradation of sulfaclozine.The second order rate constant of the reaction between sulfaclozineand (OH)-O-center dot radicals was determined by a competitive kineticsmethod and a value of (7.2 x 10(9) M-1 s(-1)) was obtained.HPLC/DAD and LC-MS/MS analysis were used to identify and follow theappearance and disappearance of sulfaclozine as well as itsintermediates. Twelve main intermediates were identified from thephotocatalytic degradation of sulfaclozine on TiO2 suspensions. Thecomparison of the evolution of those intermediates with and without theaddition of methanol showed that the quantity of eight intermediatesdecreased in the presence of methanol, one intermediate was observed toshow an increase, while three others maintained the same amount. Theseresults helped us to propose a tentative mechanism of degradationincluding (OH)-O-center dot radicals, holes, superoxide radicals andelectrons attack. In addition, TOC monitoring and mineralization duringthe photocatalytic degradation of sulfaclozine showed the release ofalmost all chlorides and the existence of the nitrogen atoms inmolecular form even after 180 min of irradiation. (C) 2015 Elsevier B.V.All rights reserved