370 research outputs found
The Relevance of Microcystin Monitoring in Dialysis Centers of Sicilians Cities: An Environmental Study
Background:
Sicilian surface basins are among the most important water supply resources available on the island. They are often affected by harmful cyanobacteria blooms as Planktothrix rubescens and Microcystis aeruginosa. Since dialysates are produced using network water, they could contain cyanotoxins. No study has been conducted yet to evaluate the removal efficiency of osmotic systems for cyanotoxins in abnormal conditions at room temperatures of about 40°C. The aim of this study was to monitor the presence of microcystins in Sicilian dialysis center, network waters and, finally, dialysates produced from these waters in an Agrigento dialysis unit where environmental conditions are favorable for algal bloom.
Methods:
This clinic normally receives surface water from artificial basins, where several times, traces of cyanobacteria have been detected. Moreover, dialysates and underground supply waters of a clinic in Catania were also sampled as control. Samplings were performed in summer 2018, when room temperatures were above 38 °C. A total of 40 samples were analyzed by ELISA assay.
Results:
Results of our monitoring highlighted concentrations of MCs in waters of several basins among LOD - 155 ng/L, lower than WHO reference value for drinking waters (1,0 µg/L), that decrease up to undetectable levels whereas no MC contamination was detected both in supply waters and dialysates.
Conclusion:
Although our first set of data outcomes seem to be quite comforting, an improvement of law and a complete census of the water supplies of dialysate centers would be ideal
Proof of the multi-Regge form of QCD amplitudes with gluon exchanges in the NLA
The multi--Regge form of QCD amplitudes with gluon exchanges is proved in the
next-to-leading approximation. The proof is based on the bootstrap relations,
which are required for the compatibility of this form with the s-channel
unitarity. We show that the fulfillment of all these relations ensures the
Reggeized form of energy dependent radiative corrections order by order in
perturbation theory. Then we prove that all these relations are fulfilled if
several bootstrap conditions on the Reggeon vertices and trajectory hold true.
Now all these conditions are checked and proved to be satisfied.Comment: 15 page
Nonperturbative and perturbative aspects of photo- and electroproduction of vector mesons
We discuss various aspects of vector meson production, first analysing the
interplay between perturbative and nonperturbative aspects of the QCD
calculation. Using a general method adapted to incorporate both perturbative
and nonpertubative aspects, we show that nonperturbative effects are important
for all experimentally available values of the photon virtuality Q2. We compare
the huge amount of experimental information now available with our theoretical
results obtained using a specific nonperturbative model without free
parameters, showing that quite simple features are able to explain the data.Comment: 19 page
A self-sustaining endocytic-based loop promotes breast cancer plasticity leading to aggressiveness and pro-metastatic behavior
The subversion of endocytic routes leads to malignant transformation and has been implicated in human cancers. However, there is scarce evidence for genetic alterations of endocytic proteins as causative in high incidence human cancers. Here, we report that Epsin 3 (EPN3) is an oncogene with prognostic and therapeutic relevance in breast cancer. Mechanistically, EPN3 drives breast tumorigenesis by increasing E-cadherin endocytosis, followed by the activation of a \u3b2-catenin/TCF4-dependent partial epithelial-to-mesenchymal transition (EMT), followed by the establishment of a TGF\u3b2-dependent autocrine loop that sustains EMT. EPN3-induced partial EMT is instrumental for the transition from in situ to invasive breast carcinoma, and, accordingly, high EPN3 levels are detected at the invasive front of human breast cancers and independently predict metastatic rather than loco-regional recurrence. Thus, we uncover an endocytic-based mechanism able to generate TGF\u3b2-dependent regulatory loops conferring cellular plasticity and invasive behavior
The Influence of Foreign vs North American Emissions on Surface Ozone in the US
As part of the Hemispheric Transport of Air Pollution (HTAP; www.htap.org) project, we analyze results from 16 global and hemispheric chemical transport models and compare these to Clean Air Status and Trends Network (CASTNet) observations in the United States (US) for 2001. Using the policy-relevant maximum daily 8-h ozone (MDA8 O3) statistic, the multi-model ensemble represents the observations well (mean r2=0.57, ensemble bias=+4.1 ppbv for all regions and all seasons) despite a wide range in the individual model results. Correlations are strongest in the NorthEastern US during spring and fall (r2=0.68); and weakest in the Midwestern US in summer (r2=0.46). However, large positive mean biases exist during summer for all Eastern US regions, ranging from 10¿20 ppbv, and a smaller negative bias is present in the Western US during spring (3 ppbv). In most all other regions and seasons, the biases of the model ensemble simulations are 5 ppbv. Sensitivity simulations in which anthropogenic O3-precursor emissions (NOx+NMVOC+CO+aerosols) were decreased by 20% in each of four source regions: East Asia (EA), South Asia (SA), Europe (EU) and North America (NA) show that the greatest response of MDA8 O3 to the summed foreign emissions reductions occurs during spring in the West (0.9 ppbv reduction due
to 20% reductions from EA+SA+EU). East Asia is the largest contributor to MDA8 O3 at all ranges of the O3 distribution for most regions (typically 0.45 ppbv). The exception is in the NorthEastern US where European emissions reductions had the greatest impact on MDA8 O3, particularly in the middle of the MDA8 O3 distribution (response of 0.35 ppbv between 35¿55 ppbv). In all regions and seasons, however, O3-precursor emissions reductions of 20% in the NA source region decrease MDA8 O3 the most by a factor of 2 to nearly 10 relative to foreign emissions reductions. The O3 response to anthropogenic NA emissions is greatest in the Eastern US during summer at the high
end of the O3 distribution (5-6 ppbv for 20% reductions). While the impact of foreign emissions on surface O3 in the US is not negligible and is of increasing concern given the growth in emissions upwind of the US - domestic emissions reductions remain a farmore effective means of decreasing MDA8 O3 values, particularly those above 75 ppb(the current US standard).JRC.H.2-Air and Climat
A Study of the Radiative Ke3 Decay and Search for Direct Photon Emission with the KLOE Detector
We present a measurement of the ratio R =
\Gamma(\keg;\Estar>30\mev,\qstar>20^\circ)\Gamma(\kegf) of data corresponding to about 3.5
million Ke3(g) events and about 9000 radiative events. Our result is R=(924 +/-
23(stat) +/-16(syst)10^{-5} for the branching ratio and X=-2.3 +/- 1.3(stat)
+/- 1.4(syst) for the parameter describing direct emission.Comment: 8 pages, 7 figure
A Numb-Mdm2 fuzzy complex reveals an isoformspecific involvement of Numb in breast cancer
Numb functions as an oncosuppressor by inhibiting Notch signaling and stabilizing p53. This latter effect depends on the interaction of Numb with Mdm2, the E3 ligase that ubiquitinates p53 and commits it to degradation. In breast cancer (BC), loss of Numb results in a reduction of p53-mediated responses including sensitivity to genotoxic drugs and maintenance of homeostasis in the stem cell compartment. In this study, we show that the Numb-Mdm2 interaction represents a fuzzy complex mediated by a short Numb sequence encompassing its alternatively spliced exon 3 (Ex3), which is necessary and sufficient to inhibit Mdm2 and prevent p53 degradation. Alterations in the Numb splicing pattern are critical in BC as shown by increased chemoresistance of tumors displaying reduced levels of Ex3-containing isoforms, an effect that could be mechanistically linked to diminished p53 levels. A reduced level of Ex3-less Numb isoforms independently predicts poor outcome in BCs harboring wild-type p53. Thus, we have uncovered an important mechanism of chemoresistance and progression in p53-competent BCs
Multi-model Ensemble Simulations of Tropospheric NO2 Compared with GOME Retrievals for the Year 2000
Abstract. We present a systematic comparison of tropospheric NO2 from 17 global atmospheric chemistry models with three state-of-the-art retrievals from the Global Ozone Monitoring Experiment (GOME) for the year 2000. The models used constant anthropogenic emissions fromIIASA/EDGAR3.2 and monthly emissions from biomass burning based on the 1997–2002 average carbon emissions from the Global Fire Emissions Database (GFED). Model output is analyzed at 10:30 local time, close to the overpasstime of the ERS-2 satellite, and collocated with the measurements to account for sampling biases due to incomplete spatiotemporal coverage of the instrument. We assessed the importanceof different contributions to the sampling bias: correlations on seasonal time scale give rise to a positive bias of 30–50% in the retrieved annual means over regions dominated by emissions from biomass burning. Over the industrial
regions of the eastern United States, Europe and eastern China the retrieved annual means have a negative bias with significant contributions (between –25% and +10% of the NO2 column) resulting from correlations on time scales from a day to a month. We present global maps of modeled and retrieved annual mean NO2 column densities, together with the corresponding ensemble means and standard deviations for models and retrievals. The spatial correlation between the individual models and retrievals are high, typically in the range 0.81–0.93 after smoothing the data to a common resolution. On average the models underestimate the retrievals in industrial regions, especially over eastern China and over the Highveld region of South Africa, and overestimate the retrievals in regions dominated by biomass burning during
the dry season. The discrepancy over South America south of the Amazon disappears when we use the GFED emissions specific to the year 2000. The seasonal cycle is analyzed in detail for eight different continental regions. Over regions dominated by biomass burning, the timing of the seasonal cycle is generally well reproduced by the models. However, over Central Africa south of the Equator the models peak one
to two months earlier than the retrievals. We further evaluate a recent proposal to reduce the NOx emission factors for savanna fires by 40% and find that this leads to an improvement of the amplitude of the seasonal cycle over the biomass burning
regions of Northern and Central Africa. In these regions the models tend to underestimate the retrievals during the wet season, suggesting that the soil emissions are higher than assumed in the models. In general, the discrepancies between
models and retrievals cannot be explained by a priori profile
assumptions made in the retrievals, neither by diurnal variations
in anthropogenic emissions, which lead to a marginal
reduction of the NO2 abundance at 10:30 local time (by 2.5–
4.1% over Europe). Overall, there are significant differences
among the various models and, in particular, among the three
retrievals. The discrepancies among the retrievals (10–50%
in the annual mean over polluted regions) indicate that the
previously estimated retrieval uncertainties have a large systematic
component. Our findings imply that top-down estimations
of NOx emissions from satellite retrievals of tropospheric
NO2 are strongly dependent on the choice of model and retrieval.JRC.H.2-Climate chang
Anisotropic flow of charged hadrons, pions and (anti-)protons measured at high transverse momentum in Pb-Pb collisions at TeV
The elliptic, , triangular, , and quadrangular, , azimuthal
anisotropic flow coefficients are measured for unidentified charged particles,
pions and (anti-)protons in Pb-Pb collisions at TeV
with the ALICE detector at the Large Hadron Collider. Results obtained with the
event plane and four-particle cumulant methods are reported for the
pseudo-rapidity range at different collision centralities and as a
function of transverse momentum, , out to GeV/.
The observed non-zero elliptic and triangular flow depends only weakly on
transverse momentum for GeV/. The small dependence
of the difference between elliptic flow results obtained from the event plane
and four-particle cumulant methods suggests a common origin of flow
fluctuations up to GeV/. The magnitude of the (anti-)proton
elliptic and triangular flow is larger than that of pions out to at least
GeV/ indicating that the particle type dependence persists out
to high .Comment: 16 pages, 5 captioned figures, authors from page 11, published
version, figures at http://aliceinfo.cern.ch/ArtSubmission/node/186
Centrality dependence of charged particle production at large transverse momentum in Pb-Pb collisions at TeV
The inclusive transverse momentum () distributions of primary
charged particles are measured in the pseudo-rapidity range as a
function of event centrality in Pb-Pb collisions at
TeV with ALICE at the LHC. The data are presented in the range
GeV/ for nine centrality intervals from 70-80% to 0-5%.
The Pb-Pb spectra are presented in terms of the nuclear modification factor
using a pp reference spectrum measured at the same collision
energy. We observe that the suppression of high- particles strongly
depends on event centrality. In central collisions (0-5%) the yield is most
suppressed with at -7 GeV/. Above
GeV/, there is a significant rise in the nuclear modification
factor, which reaches for GeV/. In
peripheral collisions (70-80%), the suppression is weaker with almost independently of . The measured nuclear
modification factors are compared to other measurements and model calculations.Comment: 17 pages, 4 captioned figures, 2 tables, authors from page 12,
published version, figures at
http://aliceinfo.cern.ch/ArtSubmission/node/284
- …