Dredging - How can we manage it to minimize impacts

Sediment plumes generated by dredging can impact sensitive receptors at significant distances from the work area. Potential impacts would normally be identified and quantified through the Environmental Impact Assessment (EIA) prior to project implementation; that may also include a degree of project optimization to reduce impacts. However, there are significant uncertainties in predicting the potential impacts at the EIA stage; key components of the dredging programme such as the dredge methodology, dredge schedule, sediment spill sources and climatic conditions encountered during dredging may not be well defined, and this will typically be reflected in the accuracy of the predictions and potentially also in the choice of mitigation measures. Proactive and informed management of the dredging programme as it is executed can often significantly reduce the risk of or minimise the negative impacts. By better understanding which components of a given programme are critical in terms of potential impacts, the programme can be optimised to minimise the risks. Through modelling and monitoring during execution, impacts may be predicted before being realized, and the dredging programme may be optimized to achieve the environmental objectives while maintaining desired production rates. An example is presented describing a combination of monitoring, both of the dredge plume and at receptor sites, and dredge plume modeling to guide the dredging works

Study of the lineshape of the chi(c1) (3872) state

A study of the lineshape of the chi(c1) (3872) state is made using a data sample corresponding to an integrated luminosity of 3 fb(-1) collected in pp collisions at center-of-mass energies of 7 and 8 TeV with the LHCb detector. Candidate chi(c1)(3872) and psi(2S) mesons from b-hadron decays are selected in the J/psi pi(+)pi(-) decay mode. Describing the lineshape with a Breit-Wigner function, the mass splitting between the chi(c1 )(3872) and psi(2S) states, Delta m, and the width of the chi(c1 )(3872) state, Gamma(Bw), are determined to be (Delta m=185.598 +/- 0.067 +/- 0.068 Mev,)(Gamma BW=1.39 +/- 0.24 +/- 0.10 Mev,) where the first uncertainty is statistical and the second systematic. Using a Flatte-inspired model, the mode and full width at half maximum of the lineshape are determined to be (mode=3871.69+0.00+0.05 MeV.)(FWHM=0.22-0.04+0.13+0.07+0.11-0.06-0.13 MeV, ) An investigation of the analytic structure of the Flatte amplitude reveals a pole structure, which is compatible with a quasibound D-0(D) over bar*(0) state but a quasivirtual state is still allowed at the level of 2 standard deviations

Measurement of the CKM angle γγ in B±→DK±B^\pm\to D K^\pm and B±→Dπ±B^\pm \to D π^\pm decays with D→KS0h+h−D \to K_\mathrm S^0 h^+ h^-

A measurement of $CP$-violating observables is performed using the decays $B^\pm\to D K^\pm$ and $B^\pm\to D \pi^\pm$, where the $D$ meson is reconstructed in one of the self-conjugate three-body final states $K_{\mathrm S}\pi^+\pi^-$ and $K_{\mathrm S}K^+K^-$ (commonly denoted $K_{\mathrm S} h^+h^-$). The decays are analysed in bins of the $D$-decay phase space, leading to a measurement that is independent of the modelling of the $D$-decay amplitude. The observables are interpreted in terms of the CKM angle $\gamma$. Using a data sample corresponding to an integrated luminosity of $9\,\text{fb}^{-1}$ collected in proton-proton collisions at centre-of-mass energies of $7$, $8$, and $13\,\text{TeV}$ with the LHCb experiment, $\gamma$ is measured to be $\left(68.7^{+5.2}_{-5.1}\right)^\circ$. The hadronic parameters $r_B^{DK}$, $r_B^{D\pi}$, $\delta_B^{DK}$, and $\delta_B^{D\pi}$, which are the ratios and strong-phase differences of the suppressed and favoured $B^\pm$ decays, are also reported

Study of the doubly charmed tetraquark T+cc

Quantum chromodynamics, the theory of the strong force, describes interactions of coloured quarks and gluons and the formation of hadronic matter. Conventional hadronic matter consists of baryons and mesons made of three quarks and quark-antiquark pairs, respectively. Particles with an alternative quark content are known as exotic states. Here a study is reported of an exotic narrow state in the D0D0π+ mass spectrum just below the D*+D0 mass threshold produced in proton-proton collisions collected with the LHCb detector at the Large Hadron Collider. The state is consistent with the ground isoscalar T+cc tetraquark with a quark content of ccu⎯⎯⎯d⎯⎯⎯ and spin-parity quantum numbers JP = 1+. Study of the DD mass spectra disfavours interpretation of the resonance as the isovector state. The decay structure via intermediate off-shell D*+ mesons is consistent with the observed D0π+ mass distribution. To analyse the mass of the resonance and its coupling to the D*D system, a dedicated model is developed under the assumption of an isoscalar axial-vector T+cc state decaying to the D*D channel. Using this model, resonance parameters including the pole position, scattering length, effective range and compositeness are determined to reveal important information about the nature of the T+cc state. In addition, an unexpected dependence of the production rate on track multiplicity is observed

Immunoactivation and immunopathogeny during active visceral leishmaniasis Imunoativação e imunopatogenia durante leishmaniose visceral ativa

Visceral leishmaniasis is caused by protozoan parasites of the Leishmania donovani complex. During active disease in humans, high levels of IFN-&#947; and TNF-&#945; detected in blood serum, and high expression of IFN-&#947; mRNA in samples of the lymphoid organs suggest that the immune system is highly activated. However, studies using peripheral blood mononuclear cells have found immunosuppression specific to Leishmania antigens; this poor immune response probably results from Leishmania antigen-engaged lymphocytes being trapped in the lymphoid organs. To allow the parasites to multiply, deactivating cytokines IL-10 and TGF-&#946; may be acting on macrophages as well as anti-Leishmania antibodies that opsonize amastigotes and induce IL-10 production in macrophages. These high activation and deactivation processes are likely to occur mainly in the spleen and liver and can be confirmed through the examination of organ samples. However, an analysis of sequential data from studies of visceral leishmaniasis in hamsters suggests that factors outside of the immune system are responsible for the early inactivation of inducible nitric oxide synthase, which occurs before the expression of deactivating cytokines. In active visceral leishmaniasis, the immune system actively participates in non-lymphoid organ lesioning. While current views only consider immunocomplex deposition, macrophages, T cells, cytokines, and immunoglobulins by diverse mechanism also play important roles in the pathogenesis.<br>A leishmaniose visceral é causada por protozoários do gênero do complexo Leishmania donovani. Durante a doença ativa no homem são detectados altos níveis de IFN-&#947; e de TNF-&#945; no soro, e elevada expressão de mRNA de IFN-&#947; em amostras de órgãos linfóides sugerindo um estado intensamente ativado do sistema imunológico. A visão atual, no entanto, refere-se à imunossupressão específica aos antígenos de Leishmania com base em estudos utilizando células mononucleares do sangue periférico; a explicação para sua resposta deficiente seria provavelmente porque os linfócitos compometidos com antígeno de Leishmania são sequestrados nos órgãos linfóides. Para permitir a proliferação do parasito, citocinas desativadoras IL-10 e TGF-&#946; atuariam nos macrófagos, bem como os anticorpos anti-Leishmania opsonizando amastigotas e induzindo a produção IL-10 pelos macrófagos. Estes processos de intensa ativação e desativação provavelmente ocorreriam no baço e fígado, principalmente, e confirmados com amostras de órgãos. No entanto, analisando dados seqüenciais obtidos na leishmaniose visceral no hamster, sugere-se provável presença de fatores fora do sistema imunológico como responsável pela inativação inicial de sintase induzível do óxido nítrico que ocorre antes da expressão de citocinas desativadoras. Na leishmaniose visceral ativa o sistema imunológico participa ativamente na lesão de órgãos não linfóides. Contrária à visão existente que considera somente mecanismos de deposição de imunocomplexos, observa-se na patogenia a participação de macrófagos, células T, citocinas e imunoglobulinas por mecanismo alternativo