1,206 research outputs found

    Plant-Derived Biostimulants Differentially Modulate Primary and Secondary Metabolites and Improve the Yield Potential of Red and Green Lettuce Cultivars

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    The use of biostimulants in modern agriculture has rapidly expanded in recent years, owing to their beneficial effects on crop yield and product quality, which have come under the scope of intensive research. Accordingly, in the present study we appraised the efficacy of two plantderived biostimulants, the legume-derived protein hydrolysates Trainer¼¼ (PH), and the tropical plant extract Auxym¼¼ (TPE) on two lettuce cultivars (green and red salanova¼¼) in terms of morpho-physiological and biochemical traits (primary and secondary metabolites). The two cultivars differed in their acquisition capacity for nitrate and other beneficial ions, their photosynthetic and transpiration rates, and their ability to synthetize and accumulate organic acids and protective metabolites. The biostimulant effect was significant for almost all the parameters examined but it was subjected to significant cultivar × biostimulant interactions, denoting a cultivardependent response to biostimulant type. Notwithstanding this interaction, biostimulant application could potentially improve the yield and quality of lettuce by stimulating plant physiological processes, as indicated by the SPAD index (leaf chlorophyll index), ACO2 (assimilation rate), E (transpiration), and WUEi (intrinsic water use efficiency), and by increasing concurrently the plant mineral content (total N, K, Ca, Mg) and the biosynthesis of organic acids (malate, citrate), phenols (caffeic acid, coumaroyl quinic acid isomer 1, dicaffeoylquinic acid isomer 1), and flavonoids (quercetin-3-O-glucuronide, quercetin-3-O-glucoside). Biostimulant action may facilitate the bio-enhancement of certain lettuce cultivars that are otherwise limited by their genetic potential, for the accumulation of specific compounds beneficial to human health

    Morpho-Metric and Specialized Metabolites Modulation of Parsley Microgreens through Selective LED Wavebands

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    Plant factories and high-tech greenhouses offer the opportunity to modulate plant growth, morphology and qualitative content through the management of artificial light (intensity, photoperiod and spectrum). In this study, three Light Emitting Diode (LED) lighting systems, with blue (B, 460 nm), red (R, 650 nm) and mixed red + green-yellow + blue (RGB) light were used to grow parsley microgreens to understand how light quality could change the phenotype and the profile of secondary metabolites. Plants showed altered morphological characteristics and higher amounts of secondary metabolites under RGB LEDs treatment. The results demonstrated that microgreens under red light showed the highest fresh yield, petiole length, coumaric acid content but also the highest nitrate content. Plants under RGB light showed the highest dry matter percentage and highest content of total and single polyphenols content, while blue light showed the highest ascorbic acid and ABTS antioxidant activity. Moreover, microgreens under red light showed more compact leaves with less intercellular spaces, while under blue and RGB light, the leaves displayed ticker spongy mesophyll with higher percentage of intercellular spaces. Therefore, the specific spectral band was able to modify not only the metabolic profile, but also it could modulate the differentiation of mesophyll cells. Light quality as a preharvest factor helps to shape the final parsley microgreens product as a whole, not only in terms of yield and quality, but also from a morpho-anatomical point of vie

    Precision Measurement of KS Meson Lifetime with the KLOE detector

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    Using a large sample of pure, slow, short lived K0 mesons collected with KLOE detector at DaFne, we have measured the KS lifetime. From a fit to the proper time distribution we find tau = (89.562 +- 0.029_stat +- 0.043_syst) ps. This is the most precise measurement today in good agreement with the world average derived from previous measurements. We observe no dependence of the lifetime on the direction of the Ks.Comment: 5 pages, 7 figure

    A comparison of populations vaccinated in a public service and in a private hospital setting in the same area

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    <p>Abstract</p> <p>Background</p> <p>Improving immunisation rates in risk groups is one of the main objectives in vaccination strategies. However, achieving high vaccination rates in children with chronic conditions is difficult. Different types of vaccine providers may differently attract high risk children.</p> <p>Aim</p> <p>To describe the characteristics of two populations of children who attended a private and a public immunisation provider in the same area. Secondarily, to determine if prevalence of patients with underlying diseases by type of provider differs and to study if the choice of different providers influences timeliness in immunisation.</p> <p>Methods</p> <p>We performed a cross-sectional study on parents of children 2 – 36 months of age who attended a private hospital immunisation service or a public immunisation office serving the same metropolitan area of Rome, Italy. Data on personal characteristics and immunisation history were collected through a face to face interview with parents of vaccinees, and compared by type of provider. Prevalence of underlying conditions was compared in the two populations. Timeliness in immunisation and its determinants were analysed through a logistic regression model.</p> <p>Results</p> <p>A total of 202 parents of children 2–36 months of age were interviewed; 104 were in the public office, and 98 in the hospital practice. Children immunised in the hospital were more frequently firstborn female children, breast fed for a longer period, with a lower birthweight, and more frequently with a previous hospitalisation. The prevalence of high risk children immunised in the hospital was 9.2 vs 0% in the public service (P = 0.001). Immunisation delay for due vaccines was higher in the hospital practice than in the public service (DTP, polio, HBV, and Hib: 39.8% vs 22.1%; P = 0.005). Anyway multivariate analyses did not reveal differences in timeliness between the public and private hospital settings.</p> <p>Conclusion</p> <p>Children with underlying diseases or a low birthweight were more frequently immunised in the hospital. This finding suggests that offering immunisations in a hospital setting may facilitate vaccination uptake in high risk groups. An integration between public and hospital practices and an effort to improve communication on vaccines to parents, may significantly increase immunisation rates in high risk groups and in the general population, and prevent immunisation delays.</p

    Determination of the b quark mass at the M_Z scale with the DELPHI detector at LEP

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    An experimental study of the normalized three-jet rate of b quark events with respect to light quarks events (light= \ell \equiv u,d,s) has been performed using the CAMBRIDGE and DURHAM jet algorithms. The data used were collected by the DELPHI experiment at LEP on the Z peak from 1994 to 2000. The results are found to agree with theoretical predictions treating mass corrections at next-to-leading order. Measurements of the b quark mass have also been performed for both the b pole mass: M_b and the b running mass: m_b(M_Z). Data are found to be better described when using the running mass. The measurement yields: m_b(M_Z) = 2.85 +/- 0.18 (stat) +/- 0.13 (exp) +/- 0.19 (had) +/- 0.12 (theo) GeV/c^2 for the CAMBRIDGE algorithm. This result is the most precise measurement of the b mass derived from a high energy process. When compared to other b mass determinations by experiments at lower energy scales, this value agrees with the prediction of Quantum Chromodynamics for the energy evolution of the running mass. The mass measurement is equivalent to a test of the flavour independence of the strong coupling constant with an accuracy of 7 permil.Comment: 24 pages, 10 figures, Accepted by Eur. Phys. J.

    Measurement and Interpretation of Fermion-Pair Production at LEP energies above the Z Resonance

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    This paper presents DELPHI measurements and interpretations of cross-sections, forward-backward asymmetries, and angular distributions, for the e+e- -> ffbar process for centre-of-mass energies above the Z resonance, from sqrt(s) ~ 130 - 207 GeV at the LEP collider. The measurements are consistent with the predictions of the Standard Model and are used to study a variety of models including the S-Matrix ansatz for e+e- -> ffbar scattering and several models which include physics beyond the Standard Model: the exchange of Z' bosons, contact interactions between fermions, the exchange of gravitons in large extra dimensions and the exchange of sneutrino in R-parity violating supersymmetry.Comment: 79 pages, 16 figures, Accepted by Eur. Phys. J.

    Study of Inclusive J/psi Production in Two-Photon Collisions at LEP II with the DELPHI Detector

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    Inclusive J/psi production in photon-photon collisions has been observed at LEP II beam energies. A clear signal from the reaction gamma gamma -> J/psi+X is seen. The number of observed N(J/psi -> mu+mu-) events is 36 +/- 7 for an integrated luminosity of 617 pb^{-1}, yielding a cross-section of sigma(J/psi+X) = 45 +/- 9 (stat) +/- 17 (syst) pb. Based on a study of the event shapes of different types of gamma gamma processes in the PYTHIA program, we conclude that (74 +/- 22)% of the observed J/psi events are due to `resolved' photons, the dominant contribution of which is most probably due to the gluon content of the photon.Comment: 13 pages, 8 figures, Accepted by Phys. Lett.

    Comparative analysis of right ventricular strain in Fabry cardiomyopathy and sarcomeric hypertrophic cardiomyopathy

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    Aims To perform a comparative analysis of right ventricle (RV) myocardial mechanics, assessed by 2D speckle-tracking echocardiography (2D-STE), between patients with Fabry disease and patients with sarcomeric disease.Methods and results Patients with Fabry cardiomyopathy (FC) (n = 28) were compared with patients with sarcomeric hypertrophic cardiomyopathy (HCM), matched for degree of left ventricle hypertrophy (LVH) and demographic characteristics (n = 112). In addition, patients with Fabry disease and no LVH [phenotype-negative carriers of pathogenic alpha-galactosidase gene mutations (GLA LVH-)] (n = 28) were compared with age and sex-matched carriers of sarcomeric gene mutations without LVH [Phenotype-negative carriers of pathogenic sarcomeric gene mutations (Sarc LVH-)] (n = 56). Standard echocardiography and 2D-STE were performed in all participants. Despite a subtle impairment of RV global longitudinal strain (RV-GLS) was common in both groups, patients with FC showed a more prominent reduction of RV free wall longitudinal strain (RV-FWS) and lower values of difference between RV-FWS and RV-GLS (Delta RV strain), in comparison to individuals with HCM (P Conclusion Patients with FC show a specific pattern of RV myocardial mechanics, characterized by a larger impairment of RV-FWS and lower Delta RV strain in comparison to patients with HCM, which may be helpful in the differential diagnosis between these two diseases.[GRAPHICS].</p

    A Determination of the Centre-of-Mass Energy at LEP2 using Radiative 2-fermion Events

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    Using e+e- -> mu+mu-(gamma) and e+e- -> qqbar(gamma) events radiative to the Z pole, DELPHI has determined the centre-of-mass energy, sqrt{s}, using energy and momentum constraint methods. The results are expressed as deviations from the nominal LEP centre-of-mass energy, measured using other techniques. The results are found to be compatible with the LEP Energy Working Group estimates for a combination of the 1997 to 2000 data sets.Comment: 20 pages, 6 figures, Accepted by Eur. Phys. J.

    Quantum numbers of the X(3872)X(3872) state and orbital angular momentum in its ρ0Jψ\rho^0 J\psi decay

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    Angular correlations in B+→X(3872)K+B^+\to X(3872) K^+ decays, with X(3872)→ρ0J/ψX(3872)\to \rho^0 J/\psi, ρ0→π+π−\rho^0\to\pi^+\pi^- and J/ψ→Ό+Ό−J/\psi \to\mu^+\mu^-, are used to measure orbital angular momentum contributions and to determine the JPCJ^{PC} value of the X(3872)X(3872) meson. The data correspond to an integrated luminosity of 3.0 fb−1^{-1} of proton-proton collisions collected with the LHCb detector. This determination, for the first time performed without assuming a value for the orbital angular momentum, confirms the quantum numbers to be JPC=1++J^{PC}=1^{++}. The X(3872)X(3872) is found to decay predominantly through S wave and an upper limit of 4%4\% at 95%95\% C.L. is set on the fraction of D wave.Comment: 16 pages, 4 figure
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