178 research outputs found

    Seed morphobiometry of wild and cultivated taxa of Phaseolus L. (Fabaceae)

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    A morphobiometric analysis of seeds of Phaseolus L. from 50 populations belonging to 31 wild and cultivated taxa was carried out. Based on the outcome of the study an identifi cation key was developed comprising 25 morphotypes of which 23 related to individual taxa The different patterns of seminal tegument allowed 31 taxa to cluster into three groups: (1) Phaseolus angustissimus Gray group (wrinkled seed coat) with two morphotypes, (2) Phaseolus lunatus L. group (smooth tegument with striae) with ten morphotypes and (3) Phaseolus vulgaris L. group (smooth tegument without striae) with 13 morphotypes. All the taxa exhibited uniformity in size and variability in tegument colour of seeds irrespective of the source of population and the type of habitat. Characterization of taxa into defi nite morphotypes and the groups could be useful for biosystematic investigations and the markerbased genetic selection approaches in this important leguminous crop

    In-vehicle Drowsy Driving Detection and Alerting

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    DTNH2211D00237/0014Drowsy driving is a common phenomenon that increases the risk for fatal and injurious crashes. Technological innovations in the form of driver monitoring and notification systems may offer potential to reduce crashes due to drowsy driving. These systems monitor the driver\u2019s drowsy driving state and issue alerts when the driver is classified by the system as drowsy. Research shows that driver notification can be effective in improving performance over relatively short drives. However, the efficacy of such systems for improving performance and changing drowsy driver decision making over longer drives is unknown. The goal of this project was to evaluate the efficacy of two notifications, a lane departure warning (LDW) and a drowsiness notification with LDW (DN/LDW). The notification conditions were compared against a no-notification baseline during 4-hour overnight drives in a high-fidelity driving simulator with an incentive method designed to replicate the motivational tradeoffs common to drowsy driving, i.e., the desire to reach a destination versus one\u2019s own safety while driving drowsy. The combined DN/LDW, but not the LDW, was effective in reducing the frequency of lane departures and also in reducing the percentage of eyelid closure (PERCLOS) prior to lane departure events compared to baseline. There was no difference between the notification conditions and baseline with respect to the frequency or timing of breaks to rest, suggesting that although notifications improved driving performance, they did not alter decision making. These results suggest that notifications may aid drowsy drivers, but in-vehicle alerts may not be effective in changing the way drowsy drivers make decisions about whether and when to stop to rest

    Diamond Detectors for the TOTEM Timing Upgrade

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    This paper describes the design and the performance of the timing detector developed by the TOTEM Collaboration for the Roman Pots (RPs) to measure the Time-Of-Flight (TOF) of the protons produced in central diffractive interactions at the LHC. The measurement of the TOF of the protons allows the determination of the longitudinal position of the proton interaction vertex and its association with one of the vertices reconstructed by the CMS detectors. The TOF detector is based on single crystal Chemical Vapor Deposition (scCVD) diamond plates and is designed to measure the protons TOF with about 50 ps time precision. This upgrade to the TOTEM apparatus will be used in the LHC run 2 and will tag the central diffractive events up to an interaction pileup of about 1. A dedicated fast and low noise electronics for the signal amplification has been developed. The digitization of the diamond signal is performed by sampling the waveform. After introducing the physics studies that will most profit from the addition of these new detectors, we discuss in detail the optimization and the performance of the first TOF detector installed in the LHC in November 2015.Comment: 26 pages, 18 figures, 2 tables, submitted for publication to JINS

    Evidence for non-exponential elastic proton-proton differential cross-section at low |t| and sqrt(s) = 8 TeV by TOTEM

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    The TOTEM experiment has made a precise measurement of the elastic proton-proton differential cross-section at the centre-of-mass energy sqrt(s) = 8 TeV based on a high-statistics data sample obtained with the beta* = 90 optics. Both the statistical and systematic uncertainties remain below 1%, except for the t-independent contribution from the overall normalisation. This unprecedented precision allows to exclude a purely exponential differential cross-section in the range of four-momentum transfer squared 0.027 < |t| < 0.2 GeV^2 with a significance greater than 7 sigma. Two extended parametrisations, with quadratic and cubic polynomials in the exponent, are shown to be well compatible with the data. Using them for the differential cross-section extrapolation to t = 0, and further applying the optical theorem, yields total cross-section estimates of (101.5 +- 2.1) mb and (101.9 +- 2.1) mb, respectively, in agreement with previous TOTEM measurements.Comment: Final version published in Nuclear Physics

    KRAS-regulated glutamine metabolism requires UCP2-mediated aspartate transport to support pancreatic cancer growth

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    The oncogenic KRAS mutation has a critical role in the initiation of human pancreatic ductal adenocarcinoma (PDAC) since it rewires glutamine metabolism to increase reduced nicotinamide adenine dinucleotide phosphate (NADPH) production, balancing cellular redox homeostasis with macromolecular synthesis1,2. Mitochondrial glutamine-derived aspartate must be transported into the cytosol to generate metabolic precursors for NADPH production2. The mitochondrial transporter responsible for this aspartate efflux has remained elusive. Here, we show that mitochondrial uncoupling protein 2 (UCP2) catalyses this transport and promotes tumour growth. UCP2-silenced KRASmut cell lines display decreased glutaminolysis, lower NADPH/NADP+ and glutathione/glutathione disulfide ratios and higher reactive oxygen species levels compared to wild-type counterparts. UCP2 silencing reduces glutaminolysis also in KRASWT PDAC cells but does not affect their redox homeostasis or proliferation rates. In vitro and in vivo, UCP2 silencing strongly suppresses KRASmut PDAC cell growth. Collectively, these results demonstrate that UCP2 plays a vital role in PDAC, since its aspartate transport activity connects the mitochondrial and cytosolic reactions necessary for KRASmut rewired glutamine metabolism2, and thus it should be considered a key metabolic target for the treatment of this refractory tumour

    Adaptive Immunity against Leishmania Nucleoside Hydrolase Maps Its C-Terminal Domain as the Target of the CD4+ T Cell–Driven Protective Response

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    Nucleoside hydrolases (NHs) show homology among parasite protozoa, fungi and bacteria. They are vital protagonists in the establishment of early infection and, therefore, are excellent candidates for the pathogen recognition by adaptive immune responses. Immune protection against NHs would prevent disease at the early infection of several pathogens. We have identified the domain of the NH of L. donovani (NH36) responsible for its immunogenicity and protective efficacy against murine visceral leishmaniasis (VL). Using recombinant generated peptides covering the whole NH36 sequence and saponin we demonstrate that protection against L. chagasi is related to its C-terminal domain (amino-acids 199–314) and is mediated mainly by a CD4+ T cell driven response with a lower contribution of CD8+ T cells. Immunization with this peptide exceeds in 36.73±12.33% the protective response induced by the cognate NH36 protein. Increases in IgM, IgG2a, IgG1 and IgG2b antibodies, CD4+ T cell proportions, IFN-γ secretion, ratios of IFN-γ/IL-10 producing CD4+ and CD8+ T cells and percents of antibody binding inhibition by synthetic predicted epitopes were detected in F3 vaccinated mice. The increases in DTH and in ratios of TNFα/IL-10 CD4+ producing cells were however the strong correlates of protection which was confirmed by in vivo depletion with monoclonal antibodies, algorithm predicted CD4 and CD8 epitopes and a pronounced decrease in parasite load (90.5–88.23%; p = 0.011) that was long-lasting. No decrease in parasite load was detected after vaccination with the N-domain of NH36, in spite of the induction of IFN-γ/IL-10 expression by CD4+ T cells after challenge. Both peptides reduced the size of footpad lesions, but only the C-domain reduced the parasite load of mice challenged with L. amazonensis. The identification of the target of the immune response to NH36 represents a basis for the rationale development of a bivalent vaccine against leishmaniasis and for multivalent vaccines against NHs-dependent pathogens

    Elastic differential cross-section measurement at root s=13 TeV by TOTEM

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    The TOTEM collaboration has measured the velastic proton-proton differential cross section d sigma/dt at root s = 13 TeV LHC energy using dedicated beta* = 90 m beam optics. The Roman Pot detectors were inserted to 10s distance from the LHC beam, which allowed the measurement of the range [0.04 GeV2; 4 GeV2] in four-momentum transfer squared vertical bar t vertical bar. The efficient data acquisition allowed to collect about 10(9) elastic events to precisely measure the differential cross-section including the diffractive minimum (dip), the subsequent maximum (bump) and the large-vertical bar t vertical bar tail. The average nuclear slope has been found to be B = (20.40 +/- 0.002(stat) +/- 0.01(syst)) GeV-2 in the vertical bar t vertical bar-range 0.04-0.2 GeV2. The dip position is vertical bar t(dip)vertical bar = (0.47 +/- 0.004(stat)+/- 0.01(syst)) GeV2. The differential cross section ratio at the bump vs. at the dip R = 1.77 +/- 0.01(stat) has been measured with high precision. The series of TOTEM elastic pp measurements show that the dip is a permanent feature of the pp differential cross-section at the TeV scale.Peer reviewe

    Elastic differential cross-section dσ/dt{\rm d}\sigma/{\rm d}t at s=\sqrt{s}=2.76 TeV and implications on the existence of a colourless 3-gluon bound state

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    The proton-proton elastic differential cross section dσ/dt{\rm d}\sigma/{\rm d}t has been measured by the TOTEM experiment at s=2.76\sqrt{s}=2.76 TeV energy with β=11\beta^{*}=11 m beam optics. The Roman Pots were inserted to 13 times the transverse beam size from the beam, which allowed to measure the differential cross-section of elastic scattering in a range of the squared four-momentum transfer (t|t|) from 0.360.36 GeV2^{2} to 0.740.74 GeV2^{2}. The differential cross-section can be described with an exponential in the t|t|-range between 0.360.36 GeV2^{2} and 0.540.54 GeV2^{2}, followed by a diffractive minimum (dip) at tdip=0.61±0.03|t_{\rm dip}| = 0.61 \pm 0.03 GeV2^{2} and a subsequent maximum (bump). The ratio of the dσ/dt{\rm d}\sigma/{\rm d}t at the bump and at the dip is 1.7±0.21.7\pm 0.2. When compared to the ppˉ\rm p\bar{p} measurement of the D0 experiment at s=1.96\sqrt s = 1.96 TeV, a significant difference can be observed. Under the condition that the effects due to the energy difference between TOTEM and D0 can be neglected, the result provides evidence for a colourless 3-gluon bound state exchange in the tt-channel of the proton-proton elastic scattering.Comment: 75 authors, 17 pages, 10 figures, 3 table

    Elastic differential cross-section dσ/dt at s√=2.76 TeV and implications on the existence of a colourless C-odd three-gluon compound state

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    The proton–proton elastic differential cross section dσ/dt has been measured by the TOTEM experiment at s√=2.76 TeV energy with β∗=11 m beam optics. The Roman Pots were inserted to 13 times the transverse beam size from the beam, which allowed to measure the differential cross-section of elastic scattering in a range of the squared four-momentum transfer (|t|) from 0.36 to 0.74 GeV2. The differential cross-section can be described with an exponential in the |t|-range between 0.36 and 0.54 GeV2, followed by a diffractive minimum (dip) at |tdip|=(0.61±0.03) GeV2 and a subsequent maximum (bump). The ratio of the dσ/dt at the bump and at the dip is 1.7±0.2. When compared to the proton–antiproton measurement of the D0 experiment at s√=1.96 TeV, a significant difference can be observed. Under the condition that the effects due to the energy difference between TOTEM and D0 can be neglected, the result provides evidence for the exchange of a colourless C-odd three-gluon compound state in the t-channel of the proton–proton and proton–antiproton elastic scattering
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