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The characterization of vehicle exhaust emissions of volatile organic compounds (VOCs) is essential to estimate their impact on the formation of secondary organic aerosol (SOA) and, more generally, air quality. This paper revises and updates non-methane volatile organic compounds (NMVOCs) tailpipe emissions of three Euro 5 vehicles during Artemis cold urban (CU) and motorway (MW) cycles. Positive matrix factorization (PMF) analysis is carried out for the first time on proton transfer reaction time-of-flight mass spectrometer (PTR-ToF-MS) datasets of vehicular emission. Statistical analysis helped to associate the emitted VOCs to specific driving conditions, such as the start of the vehicles, the activation of the catalysts, or to specific engine combustion regimes. Merged PTR-ToF-MS and automated thermal desorption gas chromatography mass spectrometer (ATD-GC-MS) datasets provided an exhaustive description of the NMVOC emission factors (EFs) of the vehicles, thus helping to identify and quantify up to 147 individual compounds. In general, emissions during the CU cycle exceed those during the MW cycle. The gasoline direct injection (GDI) vehicle exhibits the highest EF during both CU and MW cycles (252 and 15 mg/km), followed by the port-fuel injection (PFI) vehicle (24 and 0.4 mg/km), and finally the diesel vehicle (15 and 3 mg/km). For all vehicles, emissions are dominated by unburnt fuel and incomplete combustion products. Diesel emissions are mostly represented by oxygenated compounds (65%) and aliphatic hydrocarbons (23%) up to C22, while GDI and PFI exhaust emissions are composed of monoaromatics (68%) and alkanes (15%). Intermediate volatility organic compounds (IVOCs) range from 2.7 to 13% of the emissions, comprising essentially linear alkanes for the diesel vehicle, while naphthalene accounts up to 42% of the IVOC fraction for the gasoline vehicles. This work demonstrates that PMF analysis of PTR-ToF-MS datasets and GC-MS analysis of vehicular emissions provide a revised and deep characterization of vehicular emissions to enrich current emission inventories.

Atmospheric particles have several impacts on health and the environment, especially in urban areas. Parts of those particles are not fresh and have undergone atmospheric chemical and physical processes. Due to a lack of representativeness of experimental conditions and experimental artifacts such as particle wall losses in chambers, there are uncertainties on the effects of physical processes (condensation, nucleation and coagulation) and their role in particle evolution from modern vehicles. This study develops a new method to correct wall losses, accounting for size dependence and experiment-to-experiment variations. It is applied to the evolution of fresh diesel exhaust particles to characterize the physical processes which they undergo. The correction method is based on the black carbon decay and a size-dependent coefficient to correct particle distributions. Six diesel passenger cars, Euro 3 to Euro 6, were driven on a chassis dynamometer with Artemis Urban cold start and Artemis Motorway cycles. Exhaust was injected in an 8 m3 chamber with Teflon walls. The physical evolution of particles was characterized during 6 to 10 h. Increase in particle mass is observed even without photochemical reactions due to the presence of intermediate-volatility organic compounds and semi-volatile organic compounds. These compounds were quantified at emission and induce a particle mass increase up to 17 % h−1, mainly for the older vehicles (Euro 3 and Euro 4). Condensation is 4 times faster when the available particle surface is multiplied by 6.5. If initial particle number concentration is below [8–9] × 104 cm−3, a nucleation mode seems to be present but not measured by a scanning mobility particle sizer (SMPS). The growth of nucleation-mode particles results in an increase in measured [PN]. Above this threshold, particle number concentration decreases due to coagulation, up to −27 % h−1. Under those conditions, the chamber and experimental setup are well suited to characterizing and quantifying the process of coagulation.

Cued Speech is a specific linguistic code for hearing-impaired people. It is based on both lip reading and manual gestures. In the context of THIMP (Telephony for the Hearing-IMpaired Project), we work on automatic cued speech translation. In this paper, we only address the problem of automatic cued speech manual gesture recognition. Such a gesture recognition issue is really common from a theoretical point of view, but we approach it with respect to its particularities in order to derive an original method. This method is essentially built around a bioinspired method called early reduction . Prior to a complete analysis of each image of a sequence, the early reduction process automatically extracts a restricted number of key images which summarize the whole sequence. Only the key images are studied from a temporal point of view with lighter computation than the complete sequence.

Cued Speech is a specific linguistic code for hearing-impaired people. It is based on both lip reading and manual gestures. In the context of THIMP (Telephony for the Hearing-IMpaired Project), we work on automatic cued speech translation. In this paper, we only address the problem of automatic cued speech manual gesture recognition. Such a gesture recognition issue is really common from a theoretical point of view, but we approach it with respect to its particularities in order to derive an original method. This method is essentially built around a bioinspired method called early reduction. Prior to a complete analysis of each image of a sequence, the early reduction process automatically extracts a restricted number of key images which summarize the whole sequence. Only the key images are studied from a temporal point of view with lighter computation than the complete sequence.

The calorimeter system of LHCb is subdivided into four sub-detectors which provide its longitudinal segmentation: a Scintillator Pad Detector, followed by a Preshower and, then, an electromagnetic, an hadronic calorimeter. After a description of these detectors, procedures developed to calibrate their response are discussed together with the degradation of response observed due to the harsh conditions (high radiation and current levels). First results on the calorimeter performance over the two most productive years of physics data taking, 2011 and 2012 are given.

The directC\\!{P}{}{a}symmetries of the decaysB⁰ → K^(*0) μ⁺ μ⁻andB⁺ → K⁺ μ⁺ μ⁻are measured usingppcollision data corresponding to an integrated luminosity of 3.0 \\mbox{fb}{⁻¹}{}collected with the LHCb detector. The respective control modesB⁰ → J/ψ K^(*0)andB⁺ → J/ψ K⁺are used to account for detection and production asymmetries. The measurements are made in several intervals ofμ⁺ μ⁻invariant mass squared, with theφ(1020)and charmonium resonance regions excluded. Under the hypothesis of zeroC\\!{P}{}{a}symmetry in the control modes, the average values of the asymmetries are align A_(C)\\!{P}{(}{B}⁰ K^(*)0 ⁺ ⁻) &= -0.035 0.024 0.003, A_(C)\\!{P}{(}{B}⁺ K⁺ ⁺ ⁻) &= -0.012 0.017 0.001, align where the first uncertainties are statistical and the second are due to systematic effects. Both measurements are consistent with the Standard Model prediction of smallC\\!{P}{}{a}symmetry in these decays.

A measurement of the inclusiveW → μνproduction cross-section using data fromppcollisions at a centre-of-mass energy of√s̅ = 7 \\rm TeVis presented. The analysis is based on an integrated luminosity of about1.0 \\rm fb⁻¹recorded with the LHCb detector. Results are reported for muons with a transverse momentum greater than20 \\rm Ge\\kern -0.1em V\\!/cand pseudorapidity between 2.0 and 4.5. TheW⁺andW⁻production cross-sections are measured to beσ_(W⁺ → μ⁺ν) = 861.0 ± 2.0 ± 11.2 ± 14.7 \\rm pb,σ_(W⁻ → μ⁻ν̅) = 675.8 ± 1.9 ± 8.8 ± 11.6 \\rm pb,where the first uncertainty is statistical, the second is systematic and the third is due to the luminosity determination. Cross-section ratios and differential distributions as functions of the muon pseudorapidity are also presented. The ratio ofW⁺toW⁻cross-sections in the same fiducial kinematic region is determined to be((σ_(W⁺ → μ⁺ν))/(σ_(W⁻ → μ⁻ν̅))) = 1.274 ± 0.005 ± 0.009,where the uncertainties are statistical and systematic, respectively. Results are in good agreement with theoretical predictions at next-to-next-to-leading order in perturbative quantum chromodynamics.

A binned Dalitz plot analysis ofB^(±) → D K^(±)decays, withD → K_(S) π⁺π⁻andD → K_(S) K⁺ K⁻ , is performed to measure the -violating observablesx_(±)andy_(±) , which are sensitive to the Cabibbo-Kobayashi-Maskawa angleγ . The analysis exploits a sample of proton-proton collision data corresponding to 3.0ınvfb collected by the LHCb experiment. Measurements from CLEO-c of the variation of the strong-interaction phase of theDdecay over the Dalitz plot are used as inputs. The values of the parameters are found to bex₊ = ( -7.7 ± 2.4 ± 1.0 ± 0.4 )× 10⁻² ,x₋ = (2.5 ± 2.5 ± 1.0 ± 0.5) × 10⁻² ,y₊ = (-2.2 ± 2.5 ± 0.4 ± 1.0)× 10⁻² , andy₋ = (7.5 ± 2.9 ± 0.5 ± 1.4) × 10⁻² . The first, second, and third uncertainties are the statistical, the experimental systematic, and that associated with the precision of the strong-phase parameters. These are the most precise measurements of these observables and correspond toγ = (62⁺¹⁵₋₁₄)° , with a second solution atγ → γ + 180° , andr_(B) = 0.080^(+ 0.019)_(-0.021) , wherer_(B)is the ratio between the suppressed and favouredBdecay amplitudes.

A search for$CP$violation using$T$ -odd correlations is performed using the four-body$D^0 \\to K^+K^-\\pi^+\\pi^-$decay, selected from semileptonic$B$decays. The data sample corresponds to integrated luminosities of$1.0\\,\\text{fb}^{-1}$and$2.0\\,\\text{fb}^{-1}$recorded at the centre-of-mass energies of 7 TeV and 8 TeV, respectively. The$CP$ -violating asymmetry$a_{CP}^{T\\text{-odd}}$is measured to be$(0.18\\pm 0.29\\text{(stat)}\\pm 0.04\\text{(syst)})\\%$ . Searches for$CP$violation in different regions of phase space of the four-body decay, and as a function of the$D^0$decay time, are also presented. No significant deviation from the$CP$conservation hypothesis is found.

The kinematic dependences of the relative production rates,f_(Λ_(b)⁰)/f_(d) , ofΛ_(b)⁰baryons andB̄⁰mesons are measured usingΛ_(b)⁰ → Λ_(c)⁺ π⁻andB̄⁰ → D⁺ π⁻decays. The measurements use proton-proton collision data, corresponding to an integrated luminosity of 1 fb ⁻¹at a centre-of-mass energy of 7 TeV, recorded in the forward region with the LHCb experiment. The relative production rates are observed to depend on the transverse momentum,p_(T) , and pseudorapidity,η , of the beauty hadron, in the studied kinematic region1.5 < p_(T) < 40GeV/ cand2 < η < 5 . Using a previous LHCb measurement off_(Λ_(b)⁰)/f_(d)in semileptonic decays, the branching fraction𝓑(Λ_(b)⁰ → Λ_(c)⁺ π⁻) = \\Big( 4.30 ± 0.03 ^(+0.12)_(-0.11) ± 0.26 ± 0.21 \\Big) × 10⁻³is obtained, where the first uncertainty is statistical, the second is systematic, the third is from the previous LHCb measurement off_(Λ_(b)⁰)/f_(d)and the fourth is due to theB̄⁰ → D⁺ π⁻branching fraction. This is the most precise measurement of aΛ_(b)⁰branching fraction to date.