Caractérisation de deux effluents industriels au Togo :étude d’impact sur l’environnement

Characterization of two industrial effluents in Togo : environment impact studyEnvironment pollution due to two industrial effluents has been investigated. Results how that effluent derive from the factory of the treatment of Kpémé posphate ore was  loaded with settling suspended matter (> 90 % of total suspended solids). Suspended solids contained metallic elements, about 17.5 μg g-1 as cadmium (Cd) were measured. Water around the input point of the effluent (effluent is discharged in the sea) had a turbidity as high as 200 NTU. The study did not show a particular metallic contamination (Cd and Hg) of some fish species. Datcha textile industry effluent was characterized by high alkalinity (pH > 10) and by high concentrations of suspended solids (500-650 mg L-1), oxydable matter (COD = 340-380 mgO2 L-1) and organic nitrogen (30-40 mgN L-1)

Préparation des charbons actifs par voie chimique à l'acide phosphorique à base de coque de noix de coco

Les matieres ligno-cellulosiques sont des precurseurs du charbon actif. Le present travail a eu pour but la preparation de charbons actifs a partir des coques de noix de coco par activation chimique a lfacide phosphorique. Pour optimiser le procede de la preparation, les effets des concentrations de lfacide phosphorique (12,5 a 50%), des temperatures d'activation (500 α 700 °C) et des ratios d'impregnation Xp de l'acide   phosphorique/precurseur (0,7 a 2,5), sur la capacite d'adsorption de l'iode ont ete etudies. Les proprietes texturales de ceux-ci ont ete determinees par lfetude dfisotherme dfadsorption d'azote N2. Cette etude revele que dans les conditions de preparation, la valeur maximale de l'indice d'iode egale a 787 mg.g-1 avec un rendement massique egal a 37,91% est obtenue pour un ratio  dfimpregnation egal a 1,5, une concentration en acide egale a 50% et une temperature de carbonisation egale a 500°C. Ce charbon actif (avec Xp = 1,5) prepare dans les conditions optimisees, a une surface specifique BET de 1519 m2.g-1, une distribution des pores a dominance micropores (Vµ/VT = 82,4%) et un pHZPC de 3,16. Les   characteristiques chimiques par analyse spectroscopie FT-IR et la methode de Boehm ont montre la presence a la surface de ce charbon actif, desgroupes carboxyliques, phenoliques et pyrone. Il presente donc une  meilleure texture et un caractere acide.Mots cles: Charbon actif, coques de noix de coco, activation chimique, ratio dfimpregnation,isotherme dfadsorption, caracteristiques physico-chimiques

Caractérisation physico-chimique et diversité phytoplanctonique des eaux du lac de Zowla (Lac Boko), Togo

Cette étude a été initiée pour évaluer l’impact de l’eau de mer et des cours d’eau sur les caractéristiques physico-chimiques et sur la diversité phytoplanctonique de l’eau du lac de Zowla. Pour ce faire, cinq sites de prélèvement dans le lac et cinq autres dans les rivières tributaires du lac ont été retenus en Juin 2007 correspondant à la grande saison pluvieuse et en Août 2007 correspondant à la petite saison sèche. Les paramètres physico-chimiques ont été déterminés par les méthodes AFNOR. L’identification des espèces de phytoplancton a été faite au microscope photonique ordinaire. L’étude a révélé une conductivité électrique très élevée d’une valeur maximale de 8370 μS/cm au site le plus proche de la mer en Juin, confirmée par exemple par une teneur en chlorure très élevée (2723 mg /l au même site en Juin). En Août, on note une oxydabilité au KMnO4 élevée (valeur maximale : 10 mgO2/l) aux sites le plus éloigné et le plus proche de la mer. S’agissant de la diversité de la flore algale, les espèces de la classe des diatomophycées sont les plus diversifiées au cours des deux saisons, mais cette suprématie est plus marquée en grande saison pluvieuse qu’en petite saison pluvieuse (80,55% de la composition qualitative de la flore algale en Juin contre 40% en Août). L’Analyse en Composantes principales (ACP) a montré que les cyanophycées sont plus diversifiées en espèces dans les milieux aquatiques turbides riches en éléments minéraux azotés et phosphatés, les euchlorophycées le sont dans les milieux très minéralisés et que les diatomophycées sont cosmopolites. Cette étude montre en outre que les paramètres physico-chimiques du lac de Zowla sont influencés en grande saison des pluies par l’eau de mer et en petite saison sèche par l’eau du fleuve Mono.Mots clés: Pollution, Paramètre physico-chimique, Phytoplancton, La

Impacts of climate change on plant diseases – opinions and trends

There has been a remarkable scientific output on the topic of how climate change is likely to affect plant diseases in the coming decades. This review addresses the need for review of this burgeoning literature by summarizing opinions of previous reviews and trends in recent studies on the impacts of climate change on plant health. Sudden Oak Death is used as an introductory case study: Californian forests could become even more susceptible to this emerging plant disease, if spring precipitations will be accompanied by warmer temperatures, although climate shifts may also affect the current synchronicity between host cambium activity and pathogen colonization rate. A summary of observed and predicted climate changes, as well as of direct effects of climate change on pathosystems, is provided. Prediction and management of climate change effects on plant health are complicated by indirect effects and the interactions with global change drivers. Uncertainty in models of plant disease development under climate change calls for a diversity of management strategies, from more participatory approaches to interdisciplinary science. Involvement of stakeholders and scientists from outside plant pathology shows the importance of trade-offs, for example in the land-sharing vs. sparing debate. Further research is needed on climate change and plant health in mountain, boreal, Mediterranean and tropical regions, with multiple climate change factors and scenarios (including our responses to it, e.g. the assisted migration of plants), in relation to endophytes, viruses and mycorrhiza, using long-term and large-scale datasets and considering various plant disease control methods

Ethics and Nanopharmacy: Value Sensitive Design of New Drugs

Although applications are being developed and have reached the market, nanopharmacy to date is generally still conceived as an emerging technology. Its concept is ill-defined. Nanopharmacy can also be construed as a converging technology, which combines features of multiple technologies, ranging from nanotechnology to medicine and ICT. It is still debated whether its features give rise to new ethical issues or that issues associated with nanopharma are merely an extension of existing issues in the underlying fields. We argue here that, regardless of the alleged newness of the ethical issues involved, developments occasioned by technological advances affect the roles played by stakeholders in the field of nanopharmacy to such an extent that this calls for a different approach to responsible innovation in this field. Specific features associated with nanopharmacy itself and features introduced to the associated converging technologies- bring about a shift in the roles of stakeholders that call for a different approach to responsibility. We suggest that Value Sensitive Design is a suitable framework to involve stakeholders in addressing moral issues responsibly at an early stage of development of new nanopharmaceuticals

Measurement of the inclusive and dijet cross-sections of b-jets in pp collisions at sqrt(s) = 7 TeV with the ATLAS detector

The inclusive and dijet production cross-sections have been measured for jets containing b-hadrons (b-jets) in proton-proton collisions at a centre-of-mass energy of sqrt(s) = 7 TeV, using the ATLAS detector at the LHC. The measurements use data corresponding to an integrated luminosity of 34 pb^-1. The b-jets are identified using either a lifetime-based method, where secondary decay vertices of b-hadrons in jets are reconstructed using information from the tracking detectors, or a muon-based method where the presence of a muon is used to identify semileptonic decays of b-hadrons inside jets. The inclusive b-jet cross-section is measured as a function of transverse momentum in the range 20 < pT < 400 GeV and rapidity in the range |y| < 2.1. The bbbar-dijet cross-section is measured as a function of the dijet invariant mass in the range 110 < m_jj < 760 GeV, the azimuthal angle difference between the two jets and the angular variable chi in two dijet mass regions. The results are compared with next-to-leading-order QCD predictions. Good agreement is observed between the measured cross-sections and the predictions obtained using POWHEG + Pythia. MC@NLO + Herwig shows good agreement with the measured bbbar-dijet cross-section. However, it does not reproduce the measured inclusive cross-section well, particularly for central b-jets with large transverse momenta.Comment: 10 pages plus author list (21 pages total), 8 figures, 1 table, final version published in European Physical Journal

Jet energy measurement with the ATLAS detector in proton-proton collisions at root s=7 TeV

The jet energy scale and its systematic uncertainty are determined for jets measured with the ATLAS detector at the LHC in proton-proton collision data at a centre-of-mass energy of √s = 7TeV corresponding to an integrated luminosity of 38 pb-1. Jets are reconstructed with the anti-kt algorithm with distance parameters R=0. 4 or R=0. 6. Jet energy and angle corrections are determined from Monte Carlo simulations to calibrate jets with transverse momenta pT≥20 GeV and pseudorapidities {pipe}η{pipe}<4. 5. The jet energy systematic uncertainty is estimated using the single isolated hadron response measured in situ and in test-beams, exploiting the transverse momentum balance between central and forward jets in events with dijet topologies and studying systematic variations in Monte Carlo simulations. The jet energy uncertainty is less than 2. 5 % in the central calorimeter region ({pipe}η{pipe}<0. 8) for jets with 60≤pT<800 GeV, and is maximally 14 % for pT<30 GeV in the most forward region 3. 2≤{pipe}η{pipe}<4. 5. The jet energy is validated for jet transverse momenta up to 1 TeV to the level of a few percent using several in situ techniques by comparing a well-known reference such as the recoiling photon pT, the sum of the transverse momenta of tracks associated to the jet, or a system of low-pT jets recoiling against a high-pT jet. More sophisticated jet calibration schemes are presented based on calorimeter cell energy density weighting or hadronic properties of jets, aiming for an improved jet energy resolution and a reduced flavour dependence of the jet response. The systematic uncertainty of the jet energy determined from a combination of in situ techniques is consistent with the one derived from single hadron response measurements over a wide kinematic range. The nominal corrections and uncertainties are derived for isolated jets in an inclusive sample of high-pT jets. Special cases such as event topologies with close-by jets, or selections of samples with an enhanced content of jets originating from light quarks, heavy quarks or gluons are also discussed and the corresponding uncertainties are determined. © 2013 CERN for the benefit of the ATLAS collaboration

Evidence for the Higgs-boson Yukawa coupling to tau leptons with the ATLAS detector

Results of a search for H → τ τ decays are presented, based on the full set of proton-proton collision data recorded by the ATLAS experiment at the LHC during 2011 and 2012. The data correspond to integrated luminosities of 4.5 fb−1 and 20.3 fb−1 at centre-of-mass energies of √s = 7 TeV and √s = 8 TeV respectively. All combinations of leptonic (τ → `νν¯ with ` = e, µ) and hadronic (τ → hadrons ν) tau decays are considered. An excess of events over the expected background from other Standard Model processes is found with an observed (expected) significance of 4.5 (3.4) standard deviations. This excess provides evidence for the direct coupling of the recently discovered Higgs boson to fermions. The measured signal strength, normalised to the Standard Model expectation, of µ = 1.43 +0.43 −0.37 is consistent with the predicted Yukawa coupling strength in the Standard Model

Observation of associated near-side and away-side long-range correlations in √sNN=5.02 TeV proton-lead collisions with the ATLAS detector

Two-particle correlations in relative azimuthal angle (Δϕ) and pseudorapidity (Δη) are measured in √sNN=5.02  TeV p+Pb collisions using the ATLAS detector at the LHC. The measurements are performed using approximately 1  μb-1 of data as a function of transverse momentum (pT) and the transverse energy (ΣETPb) summed over 3.1<η<4.9 in the direction of the Pb beam. The correlation function, constructed from charged particles, exhibits a long-range (2<|Δη|<5) “near-side” (Δϕ∼0) correlation that grows rapidly with increasing ΣETPb. A long-range “away-side” (Δϕ∼π) correlation, obtained by subtracting the expected contributions from recoiling dijets and other sources estimated using events with small ΣETPb, is found to match the near-side correlation in magnitude, shape (in Δη and Δϕ) and ΣETPb dependence. The resultant Δϕ correlation is approximately symmetric about π/2, and is consistent with a dominant cos⁡2Δϕ modulation for all ΣETPb ranges and particle pT

Search for new phenomena in final states with an energetic jet and large missing transverse momentum in pp collisions at √ s = 8 TeV with the ATLAS detector

Results of a search for new phenomena in final states with an energetic jet and large missing transverse momentum are reported. The search uses 20.3 fb−1 of √ s = 8 TeV data collected in 2012 with the ATLAS detector at the LHC. Events are required to have at least one jet with pT > 120 GeV and no leptons. Nine signal regions are considered with increasing missing transverse momentum requirements between Emiss T > 150 GeV and Emiss T > 700 GeV. Good agreement is observed between the number of events in data and Standard Model expectations. The results are translated into exclusion limits on models with either large extra spatial dimensions, pair production of weakly interacting dark matter candidates, or production of very light gravitinos in a gauge-mediated supersymmetric model. In addition, limits on the production of an invisibly decaying Higgs-like boson leading to similar topologies in the final state are presente