La composition chimique des particules submicroniques (PM₁) a été suivie pendant plus d'un an ( juillet 2013- septembre 2014), à résolution temporelle fine (< 30 min.), à l'aide d'un analyseur ACSM pour la fraction non-réfractaire (organiques, sulfates, nitrates, ammoniums et chlorures) et d'un aethalomètre (carbone suie), complétés par une observation micro-météorologique. Une campagne intensive (juillet 2014) a enrichi le jeu de données avec le suivi de composés organiques volatils par analyse PTR-ToFMS. Le site de mesure est de type urbain de fond, sous l'influence d'une large zone industrielle et portuaire. La composition chimique des aérosols a été analysée de manière globale, saisonnière et selon 4 secteurs de vent. L'étude de la conversion SO₂-SO₄ dans le secteur industriel a montré que ce processus est favorisé à humidité relative élevée (> 70%), faible turbulence verticale (σw : 0-0.5 m sˉ¹) et faible vitesse de vent (0-2 m sˉ¹). À l'aide d'un modèle source récepteur PMF (Positive Matrix Factorization), trois sources primaires d'espèces organiques, liées au trafic, à la combustion de biomasse et à la cuisson domestique, ont été identifiées, ainsi qu'une source secondaire. Les analyses PMF saisonnière et par secteur, avec et sans contraintes, ont permis d'identifier 2 facteurs supplémentaires en secteurs marin et industriel. Quelques cas (brises de mer, épisodes de pollution et passages de bateaux) ont été étudiés, permettant dans le dernier cas d'extraire un spectre de masse moyen lié aux émissions des navires, ShOA (Ship-like Organic Aerosol). Ce facteur contribue en moyenne pour seulement 0.5% à la fraction organique particulaire mais jusqu'à plus de 90% sur de courtes périodes. / The chemical composition of submicron particles (PM₁) was monitored for over one year (July 2013-September 2014), at high temporal resolution (< 30 min), using an Aerosol Chemical Speciation Monitor (ACSM) for the non-refractory fraction (NR-PM₁ : organic, sulfate, nitrate, ammonium and chloride) and an aethalometer for black carbon (BC), together with micrometeorology parameters. An intensive campaign (July 2014) completed the data set including the monitoring of volatile organic compounds by PTR-TOFMS. The chosen site has an urban background typology, under the influence of a large area with industrial and harbor activities. The chemical composition of aerosols was analyzed globally, seasonally and using four wind sectors. A study of the SO₂-to-SO₄ conversion in the industrial sector has shown that this process is favored at high relative humidity (> 70%), low vertical turbulence (σw : 0-0.5 m sˉ¹) and low wind speed (0-2 m sˉ¹). Using PMF (Positive Matrix factorization) source receptor modeling, three primary sources of organic species, relatied to traffic, combustion of biomass and domestic cooking, have been identified, as well as a secondary source. The seasonal and sector PMF analyses, with and without constraints, helped to identify two additional factors in the marine and industrial sectors. Some specific events (sea breezes, high pollution events and nearby ship movements) were studied, allowing to extract an average mass spectrum associated with ship emissions for the latter, ShOA (Ship-like organic aerosol). This factor only contributes to 0.5% of the particulate organic fraction on average but up to more than 90% over short periods.

Les études de séroprévalence portant sur les infections au SRAS-CoV-2 doivent souvent composer avec des échantillons non-aléatoires et non-représentatifs, limitant ainsi parfois la validité externe de leurs résultats lorsque ceux-ci sont appliqués à la population générale. Dans le cadre de ce mémoire, il s’agit d’investiguer la représentativité d’une cohorte pédiatrique d’une étude longitudinale de séroprévalence (Enfants et COVID-19 : Étude de séroprévalence) et d’évaluer dans quelle mesure ses estimations de séroprévalence peuvent s’appliquer à la population pédiatrique montréalaise en général. 1 632 enfants ont fourni au point de départ un échantillon sanguin afin de déterminer leur séropositivité aux anticorps contre le SRAS-CoV-2. À l’aide d’une modélisation par régression logistique et d’un procédé de « standardisation marginale », une pondération post-stratification calculée à partir des données du recensement canadien de 2016 a été appliquée à la population d’étude. Les variations dans les estimations de séroprévalence ont finalement été évaluées. D’importantes différences dans la distribution de certaines caractéristiques sociodémographiques peuvent être observées lorsqu’on compare la population d’étude et la population générale en se basant sur les données du recensement canadien de 2016. En comparaison des estimations non-pondérées, les estimations de séroprévalence générées à partir du procédé de « standardisation marginale » montrent une variation de plusieurs points de pourcentage, allant de -0,4% à +3,2%. La pondération n’a pas induit de changement dans l’estimation de mesures relatives comme les ratios de séroprévalence. Lorsque la population d’étude est non-représentative de la population-cible, il est nécessaire de pondérer les caractéristiques sociodémographiques associées à l’issue si l’on veut appliquer les résultats plus généralement. / Prevalence studies on SARS-CoV-2 infections have often based on study populations with non-random and non-representative samples, which limits the external validity of their results when applied to the general population. The aim of this thesis was to investigate the representativeness of a pediatric cohort of a longitudinal seroprevalence study (Children and COVID-19: Seroprevalence study) and to assess to what extent its baseline estimates of seroprevalence can be applied to the Montreal pediatric population. There were 1 632 children participants who provided a blood sample at baseline, which was used to determine their seropositivity to SARS-CoV-2 antibodies. Using logistic regression modeling and a "marginal standardization" method, post-stratification weights calculated from 2016 Canadian census data were applied to the study population. Variations in seroprevalence estimates were then assessed. Significant differences in the distribution of certain sociodemographic characteristics were observed when comparing the study population and the target population based on 2016 Canadian census data. Seroprevalence estimates were generated from the “marginal standardization” approach which differed to that of the non-standardized estimates, and the differences ranges from -0,4% to +3,2%. Weighting did not change relative measures estimates, such as seroprevalence ratios. When the study population is not representative of the target population, it is necessary to weight the sociodemographic characteristics associated with the prevalence estimates, if the results will be applied more broadly.

Inledning: God vårdhygien är ett centralt begrepp inom all hälso- och sjukvård för att förhindra spridning av sjukdomsframkallande mikroorganismer, vilka kan ge upphov till vårdrelaterade infektioner. Tandvården ska därför följa Hälso- och sjukvårdslagen (1982:763) och Socialstyrelsens föreskrifter om basala hygienrutiner. I samband med Covid-19 pandemin aktualiserades vikten av vårdhygien ytterligare för att förhindra smittspridning av Covid-19 inom tandvården. Munhålan utgör en stor potentiell risk för överföring av SARS-CoV-2, men även andra mikroorganismer, särskilt vid aerosolgenererande procedurer.  Ett tidigare mastersarbete vid Odontologiska fakulteten, Malmö Universitet, påvisade brister i följsamheten med basala hygienrutiner bland tandläkarstudenter. En uppföljning har inte genomförts, vilket uppmärksammades i samband med pandemin och frågeställningen om Covid-19 syn på betydelsen av aseptik och vårdhygien väcktes.  Syfte: Undersöka tandläkarstudenters syn på vårdhygien och självbedömd följsamhet med hygienriktlinjer under Covid-19.  Material och metod: En anonym webbenkät skickades till samtliga tandläkarstudenter på kurs 4–10 vid Odontologiska fakulteten, Malmö Universitet.  Resultat: Den totala svarsfrekvensen var 54%. Resultat visade att samtliga studenter ansåg sig ha tillräckliga kunskaper om hygienrutinerna, men trots detta bröt 20% medvetet mot hygienrutinerna och 4% uppgav att de aldrig följde hygienrutinerna.  Slutsats: Den självbedömda kunskapen om hygienriktlinjer är hög, trots det är inte följsamheten med hygienriktlinjerna optimal, vilket innebär att det finns risk för spridning av vårdrelaterade infektioner. / Introduction: Good hygiene is imperative to prevent the spread of health care associated infections. Dental care must therefore comply with the Health and Medical Services Act (1982: 763) and the National Board of Health and Welfare's regulations on basic hygiene guidelines. In conjunction with the Covid-19 pandemic, the importance of hygiene measures was further emphasized to prevent the spread of Covid-19 in dentistry. The oral cavity poses a high potential risk for transmission of SARS-CoV-2, in addition to other microorganisms, especially in aerosol-generating procedures.  A previous master's thesis at the Faculty of Odontology, Malmö University, showed a deficiency in compliance with hygiene guidelines among dental students. The question if Covid-19 view of the importance of aseptic techniques and hygiene measures in dentistry was therefore raised.  Aim: Investigate dental students' views of healthcare hygiene and self-assessed aseptic measures during Covid-19.  Materials and method: An anonymous web survey was sent to all dental students in courses 4–10 at the Faculty of Odontology, Malmö University.  Results: The overall response rate was 54%. Results showed that all students considered themselves to have sufficient knowledge of the hygiene routines, but despite this, 20% of students deliberately broke the hygiene routines and 4% stated that they never followed the hygiene routines.  Conclusion: The self-assessed awareness of hygiene guidelines and aseptic techniques is high among the students, still the compliance with hygiene protocols is not optimal, meaning there is a risk of spread of healthcare associated infections.

Objetivo: Identificar los factores influyentes en la postura ante la inmunización SARSCoV-2 en estudiantes de medicina de una universidad de Lambayeque en el año 2021. Materiales y métodos: Se realizó un estudio tipo observacional transversal analítico. Se tomó a toda la población elegible,que constó de aproximadamente 160 estudiantes y se distribuyó con un muestreo probabilístico tipo estratificado. El cuestionario elaborado se basó en la encuesta online de la Organización de Consumidores y Usuarios (OCU) titulada “Encuesta OCU: los españoles y la vacuna” que fue realizada en España. Para el análisis estadístico se empleó la herramienta estadística IBM SPSS Statistics 25.0.0.0. Se tabularon las variables categóricas para la distribución de frecuencia y porcentajes, y se realizó un análisis bivariado entre las variables de interés y las variables de desenlace, mediante la prueba exacta de Fisher. Resultados: Se encuestó a 155 de 160 universitarios, el 94,8% fueron jóvenes (18-25 años). El semestre académico que representó mayor porcentaje fue octavo ciclo. La mayoría de los ítems del cuestionario obtuvieron el puntaje de 3 puntos según la escala de Likert. El 96,8% de universitarios manifestaron que sí se vacunarían tan pronto como pudieran. Se obtuvo que el factor influyente en la postura ante la inmunización SARS-CoV-2 fue el de la efectividad de la vacuna reduciendo la mortalidad por COVID – 19. Conclusiones: Se concluye que la mayoría de los estudiantes se encontraron a favor de la vacunación. Además, la efectividad de la vacuna reduciendo la mortalidad por COVID-19, fue el único factor influyente. / Objective: To identify the influential factors in the posture before SARS-CoV-2 immunization in medical students of a Lambayeque university in the year 2021. Materials and methods: An analytical cross-sectional observational study was carried out. The entire eligible population was taken, which consisted of approximately 160 college students and was distributed with a stratified probabilistic sampling. The questionnaire prepared was based on the online survey of the Organization of Consumers and Users (OCU) entitled "OCU Survey: Spaniards and the vaccine" that was carried out in Spain. For the statistical analysis, the statistical tool IBM SPSS Statistics 25.0.0.0 was used. Categorical variables were tabulated for frequency distribution and percentages, and a bivariate analysis was performed between the variables of interest and the outcome variables, using Fisher's exact test. Results: 155 of 160 university students were surveyed, 94.8% were young (18-25 years). The semester of studies that represented the highest percentage was eighth cycle. Most of the ítems in the questionnaire obtained a score of 3 points according to the Likert scale. 96.8% of university students stated that they would get vaccinated as soon as they could. It was found that the influential factor in the posture before SARS-CoV-2 immunization was the effectiveness of the vaccine in reducing mortality from COVID-19. Conclusions: It is concluded that the majority of students were in favor of vaccination. Also, the effectiveness of the vaccine in reducing mortality from COVID-19 was the only influential factor.

Bakgrund, de restriktioner och rekommendationer som människor fått förhålla sig till under COVID-19 pandemin har inneburit en annorlunda och förändrad vardag. En grupp som blivit drabbad är högskole- och universitetsstudenter som bland annat fått byta de fysiska klassrummen mot diverse online plattformar. Tidigare forskning har utförts, men hur aktivitetsmönstret har förändrats är dock mindre utforskat. Syftet med studien var att kartlägga förändring i aktivitetsmönstret hos högskole- och universitetsstudenter under COVID-19 pandemin. Metoden som användes hade en kvantitativ design i form av tvärsnittsstudie. Ett bekvämlighetsurval användes och respondenter rekryterades via sociala medier (Facebook). Populationen bestod av 49 studenter. Deskriptiv statistik användes för att beskriva insamlade data. Resultatet visade på en förändring i studenternas aktivitetsmönster och en koppling mellan förlust av meningsfulla aktiviteter, nöjdhet gällande sin aktivitetsfördelning samt upplevd vardagsbalans kunde urskiljas. Slutsats, övergripande hade förändringarna i studenternas aktivitetsmönster påverkats till det negativa. Författarna till föreliggande studie har en förhoppning om att studien ska leda till ökad förståelse gällande människors aktivitetsmönster som relaterar till den hälsoproblematik som kan uppstå under situationer som den rådande COVID-19 pandemin. / Background, this thesis describes the restrictions and recommendations that people have had to follow during the COVID-19 pandemic, and how these have led to a different and altered everyday life. College- and University students are one group that have been affected, especially since they had to switch from in-person learning to online platforms. There have been prior studies regarding the health of students and how their health has been affected during the pandemic, however the extent to which the occupational pattern of students has changed has been less explored. The purpose of this study was to investigate the change in student’s occupational patterns during the COVID-19 pandemic. The method that was used was a quantitative design. A convenience sample was used, and the respondents were recruited through social media platforms (Facebook). The population included 49 students. Descriptive statistics were used to describe the data that was collected from the survey. Results, the study showed a change in student’s occupational patterns during the COVID-19 pandemic and a connection was seen between loss of meaningful activities, satisfaction regarding their activity distribution, and perceived everyday balance. In conclusion, the overall changes in student’s occupational patterns had a negative effect. The authors expect that this study will lead to a higher understanding of the occupational patterns that relate to the health problems that can occur during situations such as the COVID-19 pandemic.

Bakgrund: Covid-19 pandemin som orsakades av Sars-Cov-2-viruset innebar en betydande utmaning för världen. I synnerhet påverkades hälso- och sjukvården av dess framfart. Sjuksköterskor som arbetade inom slutenvården under denna tid var särskilt utsatta och föremål för en rad olika upplevelser både positiva och negativa. Dessa erfarenheter är värdefulla att analysera för att bättre kunna hantera kommande pandemier. Syfte: Att undersöka sjuksköterskors upplevelser inom slutenvården under covid-19 pandemin. Metod: Litteraturöversikt genomförd i enlighet med Fribergs metod. Elva kvalitativa originalartiklar valdes från databaserna PubMed och Cinahl Complete för analys. Resultat: Tre huvudteman identifierades vilka var: Rädsla, Osäkerhet och Sjuksköterskans upplevelser rörande yrkesrollen. Slutsats: Rädsla var en dominerande upplevelse bland sjuksköterskor och antog ett flertal olika former. Sjuksköterskor upplevde även osäkerhet relaterat till det oklara kunskapsläget, föränderlig information, den egna kompetensen samt brist på material och personal. Sjuksköterskor upplevde både positiva och negativa känslor relaterade till yrkesrollen. Förberedelse i form av utbildning av sjuksköterskor och allmänhet, genomtänkta rutiner och riktlinjer samt förbättrad lagerhållning av skyddsmaterial är viktigt för att minska negativa effekter under kommande pandemier. / Background: The Covid-19-pandemic caused by the Sars-Cov-2-virus constituted a significant challenge for the world. In particular the healthcare systems were affected during its course. Nurses working within inpatient care were especially vulnerable and might have had several different experiences, which could be either negative or positive. These experiences are valuable and worth analyzing in order to be better prepared for forthcoming pandemics. Aim: To analyze nurses´experiences in inpatient care during the Covid-19 pandemic. Method: A literary overview conducted in accordance with the method of Friberg. Eleven qualitative original articles were selected from the databases PubMed and Cinahl Complete and analyzed. Results: Three main themes were identified which were: Fear, uncertainty and nurses experiences related to the profession. Conclusions: Fear was a dominant experience among nurses and took a variety of forms. Nurses also experience uncertainty related to the unclear state of knowledge, changing information, their own competence and due to a shortage of materials and other staff. Nurses experienced both positive and negative emotions in relation to their profession. Preparation in the form of eduaction for both nurses and the general public, well-thought-out routines and guidelines as well as improved stockpiling of protective equipment is essential to reduce the negative effects of future pandemics.

Purpose: To quantify the number of SARS-CoV-2 infections in students and teachers in 14 Secondary schools in eastern Saxony, Germany. Seroprevalence of SARS-CoV-2 antibodies in study population. Number of undetected cases. - Methods: Serial seroprevalence study. - Results: The role of educational settings in the SARS-CoV-2 Pandemic is still controversial. Seroprevalence increases from 0.8 to 5.9% from October to December when schools remained open and to 12.2% in March/April during a strict lockdown with closed schools. The ratio of undetected to detected cases decreased from 0.76 to 0.44 during the study period. - Conclusion: During the second and third wave of the pandemic in Germany, students and teachers are not overrepresented in SARS-CoV-2 infections. The percentage of undetected cases is moderate and decreases over time. The risk of contracting SARS-CoV-2 within the household is higher than contracting it in educational settings making school closures rather ineffective in terms of pandemic control measures or individual risk reduction in children and adolescents. - Trial registration: DRKS00022455 (July 23rd, 2020).

The outbreak of the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in December 2019 in Wuhan challenges pediatric oncologists in an unexpected way. We provide a comprehensive overview, which systematically summarizes and grades evidence (QoE) on SARS-CoV-2 infections in pediatric cancer patients at 1.5 years of pandemic. A systematic literature search in PubMed combined with an additional exploratory literature review in other international databases was conducted to identify studies on children (aged < 18 years) with a malignant disease and COVID-19 infections. In total, 45 reports on 1003 pediatric cancer patients with SARS-CoV-2 infections were identified out of 1397 reports analyzed. The clinical course of COVID-19 was reported mild or moderate in 358 patients (41.7%), whereas 11.1% of patients showed severe COVID-19. In 12.7% of patients, chemotherapy was postponed, whereas 19% of patients with different underlying malignancies received chemotherapy during SARS-CoV-2 infection. Twenty-five patients with SARS-CoV-2 infections died, potentially related to COVID-19. Conclusion: Despite a favorable COVID-19 outcome in most pediatric cancer patients, the morbidity is reported higher than in children without comorbidities. However, no severe COVID-19 complications were associated to the continuation of chemotherapy in some cohort studies and reports on two patients. Therefore, the risk of cancer progress or relapse due to interruption of chemotherapy has carefully to be weighed against the risk of severe COVID-19 disease with potentially fatal outcome.

Les vapeurs organiques émises des solvants utilisés dans le produit chimique / la nourriture / les processus pharmaceutiques, ou des stations d'entreposage de combustible d'hydrocarbure aux terminus de pétrole, peuvent être efficacement capturées par l'adsorption sur les lits de charbon actif. L'objectif général du programme de recherche est les études expérimentales et les études de simulation de l'adsorption et des pas de régénération en cas de l'enlèvement COV qui estime dans les émissions industrielles par l'Adsorption (TSA – Température Swing Adsorption et VTSA -Vacuum Température Swing Adsorption). C'est accompli par les points suivants : établir les données d'équilibre d'isotherme pour 5 COV et 8 carbones activés à 293, 313, 333 et 353 K (complètement 120 expériences d'isotherme) et les utiliser ensuite dans le modèle de simulation; développer une simulation pose pour le processus de régénération et l'adsorption; concevoir et optimiser l' expérimentale de TSA qui a été établi dans Ecole des les Mines de Nantes; concevoir et optimiser l'expérimentale de VTSA qui a été établi dans GRL ARKEMA; la validation de simulation de résultats expérimentaux de le processus TSA et VTSA. Une fois après l'achèvement de tous les objectifs, le but est de se développer et le lancement un utile de simulation complet pour l'adsorption et les pas de régénération de COV avec la coopération de la Société PROSIM. / Organic vapors emitted from solvents used in chemical / food / pharmaceutical processes, or from hydrocarbon fuel storage stations at oil terminals, can be efficiently captured by adsorption onto activated carbon beds. The overall objective of the research program is the experimental and simulation studies of the adsorption and regeneration steps in the case of VOC removal which accounts into industrial emissions by Temperature Swing Adsorption (TSA) and Vacuum Temperature Swing Adsorption (VTSA) processes. This is achieved by the following steps : to establish the isotherm equilibrium data for 5 VOCs and 8 activated carbons at 293, 313, 333, and 353 K (totally 120 isotherm experiments) and then use them in the simulation model; to develop a simulation model for adsorption and regeneration process; to design and optimize the experimental setup of Thermal Swing Adsorption (TSA) which has been established in Ecole des Mines de Nantes; to design and optimize the experimental setup of Vacuum Temperature Swing Adsorption processes (VTSA) which has been established in GRL ARKEMA unit ; simulation validation of experimental results of TSA and VTSA process. Once after the completion of all the objectives, the goal is to develop and launch a complete simulation package for adsorption and regeneration steps of VOCs with the co-operation from PROSIM Corporation.

Les aérosols fins ont un impact environnemental primordial. Ils influencent notamment la santé, ont un impact sur la visibilité et le climat. Les Aérosols Organiques Secondaires (AOS) représentent une fraction importante des aérosols fins. Les AOS résultent de la conversion d'espèces gazeuses, formées au cours de l'oxydation des composés organiques volatils (COV), en particules par des processus de nucléation et/ou condensation sur des aérosols préexistants. L'oxydation gazeuse des COV implique une myriade de composés secondaires intermédiaires pouvant participer à la formation d'AOS. Les AOS regroupent ainsi une très grande variété d'espèces. Afin d'étudier la formation d'AOS, il est nécessaire de développer des schémas chimiques décrivant explicitement la formation des composés secondaires. Le LISA a développé en collaboration avec le NCAR (National Center of Atmospheric Research) un générateur de schémas chimiques d'oxydation des composés organiques volatils : le GECKO-A (Generator for Explicit Chemistry and Kinetics of Organics in the Atmosphere). Ce travail vise à tester (i) la fiabilité de GECKO-A à reproduire les concentrations d'AOS observées lors d'expériences en chambre de simulation atmosphérique (CSA) et (ii) la sensibilité de la formation d'AOS aux paramètres physico-chimiques tels que les pressions de vapeur saturante, effets de parois des CSA ou encore aux constantes cinétiques de réaction. Afin d'évaluer la pertinence des schémas chimiques générés avec GECKO-A, le modèle a été confronté à des expériences effectuées en CSA visant à évaluer la formation d'AOS. Le paramètre clé du partitionnement des composés organiques semi-volatils est la pression de vapeur saturante (Pvap) des espèces. Les trois méthodes considérées comme les plus fiables disponibles dans la littérature ont été implémentées dans GECKO-A afin de tester la sensibilité de la formation d'AOS à l'estimation des Pvap. Les pressions de vapeur saturantes estimées par les différentes méthodes présentent des valeurs très différentes s'étalant sur plusieurs ordres de grandeur. Malgré ces divergences marquées, la concentration et la spéciation simulées pour l'AOS s'avèrent en définitive peu sensibles à la méthode utilisée pour estimer les pressions de vapeur. Aucune méthode d'estimation de Pvap n'a par ailleurs permis de réconcilier les concentrations modélisées et observées. La concentration d'AOS demeure systématiquement surestimée de l'ordre d'un facteur 2. L'absorption des composés organiques gazeux semi-volatils sur les murs d'une chambre de simulation atmosphérique a ensuite été étudiée. L'intégration de ce processus dans le modèle conduit à diminuer de façon importante les concentrations simulées en AOS, jusqu'à un facteur 2. En outre, les rendements simulés après implémentation de ce processus apparaissent en bon accord avec les rendements mesurés en CSA. L'hypothèse d'une mauvaise représentation de certains processus en phase gazeuse a également été testée via des tests de sensibilité. En particulier, la sensibilité de la formation d'AOS aux constantes de réactions entre les COV et le radical OH a été explorée. Le système a montré une grande sensibilité à la variabilité des constantes cinétiques de réaction des COV avec le radical OH, que ce soit au niveau de l'estimation de la constante cinétique ou au niveau de la détermination du site d'attaque du radical OH. La sensibilité à l'estimation des constantes de décomposition des radicaux alkoxyles a également été testée. Cette étude n'a en revanche montré que peu d'effets sur le rendement en AOS formé / Fine aerosols have an important impact on health, visibility and climate. Secondary Organic Aerosols (SOA) represent an important fraction of fine aerosol composition. SOA are formed by nucleation or condensation onto pre-existing particles of gaseous species formed during the oxidation of emitted volatile organic compounds (VOC). VOC oxidation implies a huge number of secondary intermediates which are potentially involved in SOA formation. In order to study SOA formation, it is necessary to develop chemical schemes describing explicitly the formation and condensation of the gaseous secondary intermediates. The LISA has thus developed in collaboration with NCAR (National Center of Atmospheric Research) a generator of explicit chemical schemes : GECKO-A (Generator for Explicit Chemistry and Kinetics of Organics in the Atmosphere). This work aims at testing (i) the reliability of GECKO-A to simulate observed SOA concentrations in Atmospheric Simulation Chamber (ASC) and (ii) exploring the SOA sensitivity to physico-chemical parameters such as saturation vapour pressures, chamber walls effects or kinetics rate constants. In order to assess GECKO-A's chemical schemes, the model has been confronted to chamber experiments performed to study SOA. Saturation vapour pressure (Pvap) is the key parameter controlling the gas/particles partitioning of organic compounds The three Pvap estimation methods considered as the more reliable in the literature have been implemented in GECKO-A. Pvap estimated by the three methods differs highly, up to several orders of magnitude. Despite of these discrepancies, simulated SOA concentration and speciation show a low sensitivity to the method used to estimate the Pvap. Moreover, none of the methods were able to make the model fit the observations. SOA concentration is systematically overestimated of a factor 2. Semi volatile organic compounds deposition on a chamber walls has been investigated. The implementation of this process in the model leads to a significant decrease of the simulated SOA concentrations, up to factor of 2. Simulated SOA yields are in good agreement with measured SOA yields. The hypothesis of a misrepresentation of some gaseous processes has then been investigated through sensitivity tests. SOA formation sensitivity to COV+ OH reactions rate constants has been explored. Results exhibited a high sensitivity to the rate constants estimations (regarding the rate constants values estimation, as well as the determination of the OH attack sites). The estimated alkoxy radicals decomposition rate constants have also been tested. This test showed however no significant impact on the simulated SOA yields