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Os objetivos desse artigo foram diagnosticar os impactos recorrentes no córrego Mutuca em Gurupi-TO. Executar a verificação da área da mata ciliar de um trecho exclusivo. A verificação desses conceitos para a informação de dados, aconteceu de forma visual, após uma análise dos problemas encontrados no trecho analisado. A metodologia foi baseada em referências bibliográficas do tema para embasamento teórico, visitas e registros de informações coletados no local. Conforme as coletas de informações, foram levantadas informações complementares para caracterização do projeto de recomposição da mata ciliar ao longo do trecho do córrego. Os problemas encontrados indicam que as causas estão associadas principalmente à ocupação desordenada na margem do córrego, ausência da mata ciliar em suas margens, ocasionando sinais de processos erosivos, agricultura de subsistência familiar em suas margens e disposição inadequada de resíduos sólidos.

We present here the results obtained during an intensive field campaign conducted in the framework of the French “BIO-MAÏDO” (Bio-physico-chemistry of tropical clouds at Maïdo (Réunion Island): processes and impacts on secondary organic aerosols’ formation) project. This study integrates an exhaustive chemical and microphysical characterization of cloud water obtained in March–April 2019 at Reunion Island (Indian Ocean). Fourteen cloud samples have been collected along the slope of this mountainous island. A comprehensive chemical characterization of these samples is performed, including inorganic ions, metals, oxidants, and organic matter (organic acids, sugars, amino acids, carbonyls, and low-soluble volatile organic compounds (VOCs)). Cloud water presents high molecular complexity with elevated water-soluble organic matter content partly modulated by microphysical cloud properties. As expected, our findings show the presence of compounds of marine origin in cloud water samples (e.g., chloride, sodium) demonstrating ocean–cloud exchanges. However, the non-sea salt fraction of sulphate varies between 38 and 91 %, indicating the presence of other sources. Also, the presence of amino acids and for the first time in cloud waters of sugars, clearly indicates that biological activities contribute to the cloud water chemical composition. A significant variability between events is observed in the dissolved organic content (25.5 ± 18.4 mgC L−1), with levels reaching up to 62 mgC L−1. This variability was not similar for all the measured compounds, suggesting the presence of dissimilar emission sources or production mechanisms. For that, a statistical analysis is performed based on back-trajectory calculations using the CAT (Computing Atmospheric Trajectory Tool) model associated with land cover registry. These investigations reveal that air mass origins and microphysical variables do not fully explain the variability observed in cloud chemical composition, highlighting the complexity of emission sources, multiphasic transfer, and chemical processing in clouds. Additionally, several VOCs (oxygenated and low-soluble VOCs) were analysed in both gas and aqueous phases. Significant levels of biogenic low-soluble VOCs were detected in the aqueous phase, indicating the cloud-terrestrial vegetation exchange. Cloud scavenging of VOCs is assessed and compared to Henry’s law equilibrium to evaluate potential super or sub saturation conditions. The evaluation reveals the supersaturation of low-soluble VOCs from both natural and anthropogenic sources. Our results depict even higher supersaturation of terpenoids, suggesting their importance in the aqueous phase chemistry in highly impacted tropical areas.

The puy de Dôme (pdD) altitude research station is located in the centre of France (45° 46' N, 2° 57' E, 1465 m altitude a.s.l), 16 km from the town of Clermont-Ferrand. This station is a global GAW station (PUY), and is part of the ACTRIS-2 integrating activities (H2020). Long series of meteorological parameters such as wind speed and direction, temperature, pressure, relative humidity and radiation, atmospheric trace gases (O3, NOx, SO2, CO2, CO), and physical, optical and chemical properties of aerosols (particle size, black carbon, mass,..) are available.Cartridge sampling measurements are performed to link the observations of volatile organic compounds (VOCs) within ACTRIS and GAW. A selection of VOCs, including a large set of non-methane hydrocarbons and some terpenes (isoprene, α-pinene), was measured during summer 2010, spring and summer 2011, winter 2012, summer and winter 2013, summer 2015, and twice a week in 2017, 2018 and 2019. The analysis of VOCs collected off-line on Tenax/Carbosieve III or Tenax TA cartridges was carried out using gas chromatography coupled with thermo-desorption with mass spectrometry (GC-MS).In August 2018, a new gas chromatography (GC-FID) system was installed at the station. It allows the acquisition of non-methane hydrocarbons (C5-C10) with a temporal resolution of two hours.The reactive gas measurement series are analysed in terms of observed levels (i), diurnal and seasonal variability (ii), air mass origins (iii) and sources of these gaseous pollutants (iv).(i) The level observed at the PUY station is discussed and compared with two other stations: Monte Cimone (mainly in the free troposphere) and Hohenpeissenberg (mainly in the planetary boundary layer PBL).(ii) As the height of the PBL changes with a diurnal cycle and with the seasons, the PUY station is in the different layers of the troposphere during the year impacting the measured concentrations.(iii) In order to determine the transport pathways of the air masses before their arrival at the pdD site, the HYSPLIT (Hybrid Single Particle Lagrangian Trajectory) model was used. Trajectories were classified according to their predominant transport direction prior to measurement, either continental (C), marine (M), modified marine (Mod), Mediterranean (Med), or mixed according to their trajectories. In order to determine the influence of wind direction, the pollution wind rose was determined for the main pollutants.(iv) Comparison with temperature, air mass origins, boundary layer height are used to identify the main parameters influencing the variability of VOCs. The Principal Component Analysis (PCA) has been performed to deduce correlations between the main atmospheric species and their main determinants.

Secondary organic aerosols (SOA) produced in the atmosphere from sequential oxidation of biogenic or anthropogenic volatile organic compounds (VOC) represent a significant part of the atmospheric organic aerosol. Aerosol particles can act as cloud condensation nuclei or can be scavenged by cloud droplets, where organic carbon undergo chemical and biological transformations. Due to its high complexity, a nontargeted analysis by FT-ICR MS (Fourier-transform ion cyclotron resonance mass spectrometry) has been used to characterize the dissolved organic matter at a molecular level. SOA compounds have been detected in six aqueous samples collected in 2017 at the Puy de Dome station (PUY, France). SOA tracers, produced by VOC oxidation in environmental chambers or in ambient air and characterized in previous studies by mass spectrometry, were searched by FT-ICR MS in cloudwaters. Results clearly indicate the presence of oxidation products of isoprene, α- and β-pinene, and other monoterpenes and sesquiterpenes. I...

While primary marine aerosol (PMA) is an important part of global aerosol total emissions, its chemical composition and physical flux as a function of the biogeochemical properties of the seawater still remain highly uncharacterized due to the multiplicity of physical, chemical and biological parameters that are involved in the emission process. Here, nutrient enriched-mesocosms filled with Mediterranean seawater were studied over a three-week period. PMA generated from the mesocosm waters were characterized in term of chemical composition, size distribution and size segregated cloud condensation nuclei (CCN), as a function of the seawater chlorophyll-a (Chl-a) concentration, pigment composition, virus and bacteria abundances. In all mesocosms (enriched and control mesocosms), we detected an enrichment of calcium and a deficit in chloride in the submicron PMA mass compared to the literature inorganic composition of the seawater. A positive linear correlation was found between the aerosol number concentration flux and the seawater temperature, that could be specific to the mediteranean seawater temperature and organic content. We found that the artificial phytoplankton bloom did not affect the condensation nuclei (CN) or CCN number concentration, the normalized size distribution, the CCN activation diameter or the organic fraction of the PMA compared to the control mesocosm. However, we observed correlations between the organic fraction of the Aitken mode particles and heterotrophic flagellates, viruses, and dissolved organic carbon (DOC). No correlation between the particle organic fraction and Chl-a was observed, contrary to previous observations in natural bloom mesocosm experiments. We believe that this could be due to (1) different complexities compared to natural bloom systems, or (2) longer time periods needed to observe correlation trends.

International audience; Airborne cesium isotopes (134Cs and 137Cs) released during the Fukushima nuclear accident were transported all around the world attached to particles and reached France about 12 days after the first explosion. Concentration of cesium isotopes in cloud water sampled at the summit of the Puy de Dôme mountain (1465 m a.s.l.) increased by a factor of at least 40. During the following weeks, the concentrations decreased more slowly in cloud water than in rain and in rain compared with what was found on the aerosol phase. Cesium-134 was detectable in the aerosol phase, in rain and in cloud water for 3 months, 11 months and 18 months after the accident, respectively. These kinetics are consistent with the washout scavenging of aerosol in the lower layers of the atmosphere that leads to a relative depletion of Fukushima-labeled aerosols at ground level. Airborne particles at high altitudes, i.e. where clouds form, have a longer residence time. This finding has implications on the different time scales at which a contamination may be transferred to the ground, depending if it is transferred via dry or wet deposition. This study highlights that cloud water is a relevant type of environmental sample to attest the presence of radionuclides on a longer time scale than for the aerosol phase, provided that the metrology is able to lower usual detection limits. Rainout efficiency was computed for 137Cs.

While atmospheric new particle formation (NPF) has been observed in various environments and was found to contribute significantly to the total aerosol particle concentration, the production of new particles over open seas is poorly documented in the literature. Nucleation events were detected and analysed over the Mediterranean Sea using two condensation particle counters and a scanning mobility particle sizer on board the ATR-42 research aircraft during flights conducted between 11 September and 4 November 2012 in the framework of the HYMEX (HYdrological cycle in Mediterranean EXperiment) project. The main purpose of the present work was to characterize the spatial extent of the NPF process, both horizontally and vertically. Our findings show that nucleation is occurring over large areas above the Mediterranean Sea in all air mass types. Maximum concentrations of particles in the size range 5–10 nm (N5–10) do not systematically coincide with lower fetches (time spent by the air mass over the sea before sampling), and significant N5–10 values are found for fetches between 0 and 60 h depending on the air mass type. These observations suggest that nucleation events could be more influenced by local precursors originating from emission processes occurring above the sea, rather than linked to synoptic history. Vertical soundings were performed, giving the opportunity to examine profiles of the N5–10 concentration and to analyse the vertical extent of NPF. Our observations demonstrate that the process could be favoured above 1000 m, i.e. frequently in the free troposphere, and more especially between 2000 and 3000 m, where the NPF frequency is close to 50 %. This vertical distribution of NPF might be favoured by the gradients of several atmospheric parameters, together with the mixing of two air parcels, which could also explain the occurrence of the process at preferential altitudes. In addition, increased condensation sinks collocated with high concentrations of small particles suggest the occurrence of NPF events promoted by inputs from the boundary layer, most probably associated with convective clouds and their outflow. After their formation, particles slowly grow at higher altitudes to diameters of at least 30 nm while not being greatly depleted or affected by coagulation. Our analysis of the particle size distributions suggests that particle growth could decrease with increasing altitude.

Dissertação de mestrado em Engenharia Informática, In this busy society of ours, people push their limits to work better and harder/longer in order to remain competitive with their peers. The activities of the working population have increased daily which have, in turn, created more stressful situations and conditioned the welfare as well as the physical and mental abilities of the person. Nonetheless, working longer hours does not necessarily improve productivity nor performance. In order to prevent the negative consequences of this increasing trend, the evolution of performance throughout the workday should be more closely monitored.It is acknowledged that, during the day, the user is subjected to various factors that can affect his performance, such as stress. Stress is an ever-present factor these days and can be considered a major health problem. However, there also positives aspects, and this has made it an increasingly interesting topic of study in the scientific community. This work focuses on the interaction of stress with music, a broad phenomenon which is present in all societies. More specifically, we study the effects of music on human stress levels and emotions while performing daily activities, through the analysis the performance, try to understand how decreases along the day and how different types of music affect this phenomenon. The hypothesis presented here is analysed through a research study, which enables us to understand the effect of music on people and on their lives, more precisely in their performance at work. The results show not only that the type of music matters, but also that it is important to note the individual’s objective in each moment, as well as his personal preferences regarding music. With the results the aim is to create a music recommendation system based on the user’s stress level and the user’s performance, through the user’s interaction with the computer., Na sociedade atual as pessoas são cada mais vezes testadas até aos seus limites para poderem trabalhar mais e melhor, a fim de manter a competitividade ao máximo nível. As atividades do dia a dia da população continuam aumentar, o que cria situações de mais stress condicionando o bem-estar, bem como as capacidades físicas e mentais da pessoa. No entanto, trabalhar mais horas não significa necessariamente uma melhora da produtividade ou performance. A fim de evitar as consequências negativas desta tendência crescente, a evolução da performance ao longo de um dia de trabalho deve ser acompanhado mais de perto. É importante perceber que durante o dia as pessoas estão sujeitas a vários factores que podem afetar a sua performance, como o stress. O stress é um factor cada vez mais presente nos dias de hoje e pode ser considerado um problema. No entanto, há também aspectos positivos, tornando-se um tema cada vez mais interessante de estudo na comunidade científica. Neste trabalho é realizado um estudo, que terá como objectivo perceber a interação do stress com a música, um fenómeno presente em todas as sociedades. Especificamente, estudar os efeitos da música a nível de stress e emoções durante a execução das atividades diárias, através da análise da performance, no qual tentamos entender como está decresce ao longo do dia e como diferentes tipos de musica afeta este fenómeno. Esta hipótese apresentada é analisada através do estudo da performance, no qual nos permite entender os efeitos da musica nas pessoas e na suas vidas, mais precisamente das suas performance durante os seus trabalhos. Os resultados demonstra nos que não é so importante o tipo de musica, mas tambem é importante perceber o objectivo do utilizador bem como as suas preferencias musicais. Com os resultados obtidos o principal objectivo é criar um sistema de recomendação de musica baseado nos níveis de stress e performance do utilizador, através da interação do utilizador com o computador., The activities of working population increase daily in our society, which create more stressful situations and condition the welfare as well as the physical and mental abilities of the person. Stress is a factor more present these days and can be considered a problem. However, there also positives aspects, making it an increasingly interesting topic of study in the scientific community. In this work a study will be carried out that will focus on the interaction of stress with music, a broad phenomenon, present in all societies. Specifically, we will be study the effects of music on human stress level while performing daily activities.